/*
- * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Copyright (c) 2000-2020 Apple Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* @OSF_COPYRIGHT@
*/
-/*
+/*
* Mach Operating System
* Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
* All Rights Reserved.
- *
+ *
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
- *
+ *
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
- *
+ *
* Carnegie Mellon requests users of this software to return to
- *
+ *
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
- *
+ *
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
* Zone-based memory allocator. A zone is a collection of fixed size
* data blocks for which quick allocation/deallocation is possible.
*/
-#include <zone_debug.h>
-#include <norma_vm.h>
-#include <mach_kdb.h>
+#define ZALLOC_ALLOW_DEPRECATED 1
+#if !ZALLOC_TEST
#include <mach/mach_types.h>
#include <mach/vm_param.h>
#include <mach/kern_return.h>
#include <mach/mach_host_server.h>
+#include <mach/task_server.h>
#include <mach/machine/vm_types.h>
-#include <mach_debug/zone_info.h>
+#include <mach/vm_map.h>
+#include <mach/sdt.h>
+#include <kern/bits.h>
+#include <kern/startup.h>
#include <kern/kern_types.h>
#include <kern/assert.h>
+#include <kern/backtrace.h>
#include <kern/host.h>
#include <kern/macro_help.h>
#include <kern/sched.h>
-#include <kern/lock.h>
+#include <kern/locks.h>
#include <kern/sched_prim.h>
#include <kern/misc_protos.h>
#include <kern/thread_call.h>
-#include <kern/zalloc.h>
+#include <kern/zalloc_internal.h>
#include <kern/kalloc.h>
+#include <prng/random.h>
+
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
+#include <vm/vm_pageout.h>
+#include <vm/vm_compressor.h> /* C_SLOT_PACKED_PTR* */
+
+#include <pexpert/pexpert.h>
#include <machine/machparam.h>
+#include <machine/machine_routines.h> /* ml_cpu_get_info */
-#if defined(__ppc__)
-/* for fake zone stat routines */
-#include <ppc/savearea.h>
-#include <ppc/mappings.h>
-#endif
+#include <os/atomic.h>
-#if MACH_ASSERT
-/* Detect use of zone elt after freeing it by two methods:
- * (1) Range-check the free-list "next" ptr for sanity.
- * (2) Store the ptr in two different words, and compare them against
- * each other when re-using the zone elt, to detect modifications;
- */
-
-#if defined(__alpha)
-
-#define is_kernel_data_addr(a) \
- (!(a) || (IS_SYS_VA(a) && !((a) & (sizeof(long)-1))))
-
-#else /* !defined(__alpha) */
-
-#define is_kernel_data_addr(a) \
- (!(a) || ((a) >= vm_min_kernel_address && !((a) & 0x3)))
-
-#endif /* defined(__alpha) */
-
-/* Should we set all words of the zone element to an illegal address
- * when it is freed, to help catch usage after freeing? The down-side
- * is that this obscures the identity of the freed element.
- */
-boolean_t zfree_clear = FALSE;
-
-#define ADD_TO_ZONE(zone, element) \
-MACRO_BEGIN \
- if (zfree_clear) \
- { unsigned int i; \
- for (i=1; \
- i < zone->elem_size/sizeof(vm_offset_t) - 1; \
- i++) \
- ((vm_offset_t *)(element))[i] = 0xdeadbeef; \
- } \
- ((vm_offset_t *)(element))[0] = (zone)->free_elements; \
- (zone)->free_elements = (vm_offset_t) (element); \
- (zone)->count--; \
-MACRO_END
-
-#define REMOVE_FROM_ZONE(zone, ret, type) \
-MACRO_BEGIN \
- (ret) = (type) (zone)->free_elements; \
- if ((ret) != (type) 0) { \
- if (!is_kernel_data_addr(((vm_offset_t *)(ret))[0])) { \
- panic("A freed zone element has been modified.\n"); \
- } \
- (zone)->count++; \
- (zone)->free_elements = *((vm_offset_t *)(ret)); \
- } \
-MACRO_END
-#else /* MACH_ASSERT */
-
-#define ADD_TO_ZONE(zone, element) \
-MACRO_BEGIN \
- *((vm_offset_t *)(element)) = (zone)->free_elements; \
- (zone)->free_elements = (vm_offset_t) (element); \
- (zone)->count--; \
-MACRO_END
-
-#define REMOVE_FROM_ZONE(zone, ret, type) \
-MACRO_BEGIN \
- (ret) = (type) (zone)->free_elements; \
- if ((ret) != (type) 0) { \
- (zone)->count++; \
- (zone)->free_elements = *((vm_offset_t *)(ret)); \
- } \
-MACRO_END
-
-#endif /* MACH_ASSERT */
-
-#if ZONE_DEBUG
-#define zone_debug_enabled(z) z->active_zones.next
-#define ROUNDUP(x,y) ((((x)+(y)-1)/(y))*(y))
-#define ZONE_DEBUG_OFFSET ROUNDUP(sizeof(queue_chain_t),16)
-#endif /* ZONE_DEBUG */
+#include <libkern/OSDebug.h>
+#include <libkern/OSAtomic.h>
+#include <libkern/section_keywords.h>
+#include <sys/kdebug.h>
+#include <san/kasan.h>
+
+#if KASAN_ZALLOC
/*
- * Support for garbage collection of unused zone pages:
+ * Set to 0 to debug poisoning and ZC_ZFREE_CLEARMEM validation under kasan.
+ * Otherwise they are double-duty with what kasan already does.
*/
+#define ZALLOC_ENABLE_POISONING 0
+#define ZONE_ENABLE_LOGGING 0
+#elif DEBUG || DEVELOPMENT
+#define ZALLOC_ENABLE_POISONING 1
+#define ZONE_ENABLE_LOGGING 1
+#else
+#define ZALLOC_ENABLE_POISONING 1
+#define ZONE_ENABLE_LOGGING 0
+#endif
-struct zone_page_table_entry {
- struct zone_page_table_entry *link;
- short alloc_count;
- short collect_count;
-};
-
-/* Forwards */
-void zone_page_init(
- vm_offset_t addr,
- vm_size_t size,
- int value);
+#if __LP64__
+#define ZALLOC_EARLY_GAPS 1
+#else
+#define ZALLOC_EARLY_GAPS 0
+#endif
-void zone_page_alloc(
- vm_offset_t addr,
- vm_size_t size);
+#if DEBUG
+#define z_debug_assert(expr) assert(expr)
+#else
+#define z_debug_assert(expr) (void)(expr)
+#endif
-void zone_page_free_element(
- struct zone_page_table_entry **free_pages,
- vm_offset_t addr,
- vm_size_t size);
+extern void vm_pageout_garbage_collect(int collect);
-void zone_page_collect(
- vm_offset_t addr,
- vm_size_t size);
+/* Returns pid of the task with the largest number of VM map entries. */
+extern pid_t find_largest_process_vm_map_entries(void);
-boolean_t zone_page_collectable(
- vm_offset_t addr,
- vm_size_t size);
+/*
+ * Callout to jetsam. If pid is -1, we wake up the memorystatus thread to do asynchronous kills.
+ * For any other pid we try to kill that process synchronously.
+ */
+extern boolean_t memorystatus_kill_on_zone_map_exhaustion(pid_t pid);
-void zone_page_keep(
- vm_offset_t addr,
- vm_size_t size);
+extern zone_t vm_map_entry_zone;
+extern zone_t vm_object_zone;
-void zalloc_async(
- thread_call_param_t p0,
- thread_call_param_t p1);
+#define ZONE_MIN_ELEM_SIZE sizeof(uint64_t)
+#define ZONE_MAX_ALLOC_SIZE (32 * 1024)
+struct zone_page_metadata {
+ /* The index of the zone this metadata page belongs to */
+ zone_id_t zm_index : 11;
-#if ZONE_DEBUG && MACH_KDB
-int zone_count(
- zone_t z,
- int tail);
-#endif /* ZONE_DEBUG && MACH_KDB */
+ /* Whether `zm_bitmap` is an inline bitmap or a packed bitmap reference */
+ uint16_t zm_inline_bitmap : 1;
-vm_map_t zone_map = VM_MAP_NULL;
+ /*
+ * Zones allocate in "chunks" of zone_t::z_chunk_pages consecutive
+ * pages, or zpercpu_count() pages if the zone is percpu.
+ *
+ * The first page of it has its metadata set with:
+ * - 0 if none of the pages are currently wired
+ * - the number of wired pages in the chunk (not scaled for percpu).
+ *
+ * Other pages in the chunk have their zm_chunk_len set to
+ * ZM_SECONDARY_PAGE or ZM_SECONDARY_PCPU_PAGE depending on whether
+ * the zone is percpu or not. For those, zm_page_index holds the
+ * index of that page in the run.
+ */
+ uint16_t zm_chunk_len : 4;
+#define ZM_CHUNK_LEN_MAX 0x8
+#define ZM_SECONDARY_PAGE 0xe
+#define ZM_SECONDARY_PCPU_PAGE 0xf
+
+ union {
+#define ZM_ALLOC_SIZE_LOCK 1u
+ uint16_t zm_alloc_size; /* first page only */
+ uint16_t zm_page_index; /* secondary pages only */
+ };
+ union {
+ uint32_t zm_bitmap; /* most zones */
+ uint32_t zm_bump; /* permanent zones */
+ };
+
+ zone_pva_t zm_page_next;
+ zone_pva_t zm_page_prev;
+};
+static_assert(sizeof(struct zone_page_metadata) == 16, "validate packing");
-zone_t zone_zone = ZONE_NULL; /* the zone containing other zones */
+__enum_closed_decl(zone_addr_kind_t, bool, {
+ ZONE_ADDR_FOREIGN,
+ ZONE_ADDR_NATIVE,
+});
+#define ZONE_ADDR_KIND_COUNT 2
-/*
- * The VM system gives us an initial chunk of memory.
- * It has to be big enough to allocate the zone_zone
+/*!
+ * @typedef zone_element_t
+ *
+ * @brief
+ * Type that represents a "resolved" zone element.
+ *
+ * @description
+ * This type encodes an element pointer as a tuple of:
+ * { chunk base, element index, element protection }.
+ *
+ * The chunk base is extracted with @c trunc_page()
+ * as it is always page aligned, and occupies the bits above @c PAGE_SHIFT.
+ *
+ * The low two bits encode the protection mode (see @c zprot_mode_t).
+ *
+ * The other bits encode the element index in the chunk rather than its address.
*/
+typedef struct zone_element {
+ vm_offset_t ze_value;
+} zone_element_t;
-vm_offset_t zdata;
-vm_size_t zdata_size;
+/*!
+ * @typedef zone_magazine_t
+ *
+ * @brief
+ * Magazine of cached allocations.
+ *
+ * @field zm_cur how many elements this magazine holds (unused while loaded).
+ * @field zm_link linkage used by magazine depots.
+ * @field zm_elems an array of @c zc_mag_size() elements.
+ */
+typedef struct zone_magazine {
+ uint16_t zm_cur;
+ STAILQ_ENTRY(zone_magazine) zm_link;
+ zone_element_t zm_elems[0];
+} *zone_magazine_t;
+
+/*!
+ * @typedef zone_cache_t
+ *
+ * @brief
+ * Magazine of cached allocations.
+ *
+ * @discussion
+ * Below is a diagram of the caching system. This design is inspired by the
+ * paper "Magazines and Vmem: Extending the Slab Allocator to Many CPUs and
+ * Arbitrary Resources" by Jeff Bonwick and Jonathan Adams and the FreeBSD UMA
+ * zone allocator (itself derived from this seminal work).
+ *
+ * It is divided into 3 layers:
+ * - the per-cpu layer,
+ * - the recirculation depot layer,
+ * - the Zone Allocator.
+ *
+ * The per-cpu and recirculation depot layer use magazines (@c zone_magazine_t),
+ * which are stacks of up to @c zc_mag_size() elements.
+ *
+ * <h2>CPU layer</h2>
+ *
+ * The CPU layer (@c zone_cache_t) looks like this:
+ *
+ * ╭─ a ─ f ─┬───────── zm_depot ──────────╮
+ * │ ╭─╮ ╭─╮ │ ╭─╮ ╭─╮ ╭─╮ ╭─╮ ╭─╮ │
+ * │ │#│ │#│ │ │#│ │#│ │#│ │#│ │#│ │
+ * │ │#│ │ │ │ │#│ │#│ │#│ │#│ │#│ │
+ * │ │ │ │ │ │ │#│ │#│ │#│ │#│ │#│ │
+ * │ ╰─╯ ╰─╯ │ ╰─╯ ╰─╯ ╰─╯ ╰─╯ ╰─╯ │
+ * ╰─────────┴─────────────────────────────╯
+ *
+ * It has two pre-loaded magazines (a)lloc and (f)ree which we allocate from,
+ * or free to. Serialization is achieved through disabling preemption, and only
+ * the current CPU can acces those allocations. This is represented on the left
+ * hand side of the diagram above.
+ *
+ * The right hand side is the per-cpu depot. It consists of @c zm_depot_count
+ * full magazines, and is protected by the @c zm_depot_lock for access.
+ * The lock is expected to absolutely never be contended, as only the local CPU
+ * tends to access the local per-cpu depot in regular operation mode.
+ *
+ * However unlike UMA, our implementation allows for the zone GC to reclaim
+ * per-CPU magazines aggresively, which is serialized with the @c zm_depot_lock.
+ *
+ *
+ * <h2>Recirculation Depot</h2>
+ *
+ * The recirculation depot layer is a list similar to the per-cpu depot,
+ * however it is different in two fundamental ways:
+ *
+ * - it is protected by the regular zone lock,
+ * - elements referenced by the magazines in that layer appear free
+ * to the zone layer.
+ *
+ *
+ * <h2>Magazine circulation and sizing</h2>
+ *
+ * The caching system sizes itself dynamically. Operations that allocate/free
+ * a single element call @c zone_lock_nopreempt_check_contention() which records
+ * contention on the lock by doing a trylock and recording its success.
+ *
+ * This information is stored in the @c z_contention_cur field of the zone,
+ * and a windoed moving average is maintained in @c z_contention_wma.
+ * Each time a CPU registers any contention, it will also allow its own per-cpu
+ * cache to grow, incrementing @c zc_depot_max, which is how the per-cpu layer
+ * might grow into using its local depot.
+ *
+ * Note that @c zc_depot_max assume that the (a) and (f) pre-loaded magazines
+ * on average contain @c zc_mag_size() elements.
+ *
+ * When a per-cpu layer cannot hold more full magazines in its depot,
+ * then it will overflow about 1/3 of its depot into the recirculation depot
+ * (see @c zfree_cached_slow(). Conversely, when a depot is empty, then it will
+ * refill its per-cpu depot to about 1/3 of its size from the recirculation
+ * depot (see @c zalloc_cached_slow()).
+ *
+ * Lastly, the zone layer keeps track of the high and low watermark of how many
+ * elements have been free per period of time (including being part of the
+ * recirculation depot) in the @c z_elems_free_min and @c z_elems_free_max
+ * fields. A weighted moving average of the amplitude of this is maintained in
+ * the @c z_elems_free_wss which informs the zone GC on how to gently trim
+ * zones without hurting performance.
+ *
+ *
+ * <h2>Security considerations</h2>
+ *
+ * The zone caching layer has been designed to avoid returning elements in
+ * a strict LIFO behavior: @c zalloc() will allocate from the (a) magazine,
+ * and @c zfree() free to the (f) magazine, and only swap them when the
+ * requested operation cannot be fulfilled.
+ *
+ * The per-cpu overflow depot or the recirculation depots are similarly used
+ * in FIFO order.
+ *
+ * More importantly, when magazines flow through the recirculation depot,
+ * the elements they contain are marked as "free" in the zone layer bitmaps.
+ * Because allocations out of per-cpu caches verify the bitmaps at allocation
+ * time, this acts as a poor man's double-free quarantine. The magazines
+ * allow to avoid the cost of the bit-scanning involved in the zone-level
+ * @c zalloc_item() codepath.
+ *
+ *
+ * @field zc_alloc_cur denormalized number of elements in the (a) magazine
+ * @field zc_free_cur denormalized number of elements in the (f) magazine
+ * @field zc_alloc_elems a pointer to the array of elements in (a)
+ * @field zc_free_elems a pointer to the array of elements in (f)
+ *
+ * @field zc_depot_lock a lock to access @c zc_depot, @c zc_depot_cur.
+ * @field zc_depot a list of @c zc_depot_cur full magazines
+ * @field zc_depot_cur number of magazines in @c zc_depot
+ * @field zc_depot_max the maximum number of elements in @c zc_depot,
+ * protected by the zone lock.
+ */
+typedef struct zone_cache {
+ uint16_t zc_alloc_cur;
+ uint16_t zc_free_cur;
+ uint16_t zc_depot_cur;
+ uint16_t __zc_padding;
+ zone_element_t *zc_alloc_elems;
+ zone_element_t *zc_free_elems;
+ hw_lock_bit_t zc_depot_lock;
+ uint32_t zc_depot_max;
+ struct zone_depot zc_depot;
+} *zone_cache_t;
+
+static __security_const_late struct {
+ struct zone_map_range zi_map_range[ZONE_ADDR_KIND_COUNT];
+ struct zone_map_range zi_meta_range; /* debugging only */
+ struct zone_map_range zi_bits_range; /* bits buddy allocator */
-#define lock_zone(zone) \
-MACRO_BEGIN \
- mutex_lock(&(zone)->lock); \
-MACRO_END
+ /*
+ * The metadata lives within the zi_meta_range address range.
+ *
+ * The correct formula to find a metadata index is:
+ * absolute_page_index - page_index(MIN(zi_map_range[*].min_address))
+ *
+ * And then this index is used to dereference zi_meta_range.min_address
+ * as a `struct zone_page_metadata` array.
+ *
+ * To avoid doing that substraction all the time in the various fast-paths,
+ * zi_meta_base are pre-offset with that minimum page index to avoid redoing
+ * that math all the time.
+ *
+ * Do note that the array might have a hole punched in the middle,
+ * see zone_metadata_init().
+ */
+ struct zone_page_metadata *zi_meta_base;
+} zone_info;
-#define unlock_zone(zone) \
-MACRO_BEGIN \
- mutex_unlock(&(zone)->lock); \
-MACRO_END
+/*
+ * Initial array of metadata for stolen memory.
+ *
+ * The numbers here have to be kept in sync with vm_map_steal_memory()
+ * so that we have reserved enough metadata.
+ *
+ * After zone_init() has run (which happens while the kernel is still single
+ * threaded), the metadata is moved to its final dynamic location, and
+ * this array is unmapped with the rest of __startup_data at lockdown.
+ */
+#if CONFIG_GZALLOC
+#define ZONE_FOREIGN_META_INLINE_COUNT 20032
+#else
+#define ZONE_FOREIGN_META_INLINE_COUNT 64
+#endif
+__startup_data
+static struct zone_page_metadata
+ zone_foreign_meta_array_startup[ZONE_FOREIGN_META_INLINE_COUNT];
-#define zone_wakeup(zone) thread_wakeup((event_t)(zone))
-#define zone_sleep(zone) \
- thread_sleep_mutex((event_t)(zone), \
- &(zone)->lock, \
- THREAD_UNINT)
+/*
+ * The zone_locks_grp allows for collecting lock statistics.
+ * All locks are associated to this group in zinit.
+ * Look at tools/lockstat for debugging lock contention.
+ */
+static LCK_GRP_DECLARE(zone_locks_grp, "zone_locks");
+static LCK_MTX_EARLY_DECLARE(zone_metadata_region_lck, &zone_locks_grp);
-#define lock_zone_init(zone) \
-MACRO_BEGIN \
- mutex_init(&zone->lock, 0); \
-MACRO_END
+/*
+ * Exclude more than one concurrent garbage collection
+ */
+static LCK_GRP_DECLARE(zone_gc_lck_grp, "zone_gc");
+static LCK_MTX_EARLY_DECLARE(zone_gc_lock, &zone_gc_lck_grp);
-#define lock_try_zone(zone) mutex_try(&zone->lock)
+bool panic_include_zprint = FALSE;
+mach_memory_info_t *panic_kext_memory_info = NULL;
+vm_size_t panic_kext_memory_size = 0;
-kern_return_t zget_space(
- vm_offset_t size,
- vm_offset_t *result);
+/*
+ * Protects zone_array, num_zones, num_zones_in_use, and
+ * zone_destroyed_bitmap
+ */
+static SIMPLE_LOCK_DECLARE(all_zones_lock, 0);
+static zone_id_t num_zones_in_use;
+zone_id_t _Atomic num_zones;
+SECURITY_READ_ONLY_LATE(unsigned int) zone_view_count;
-decl_simple_lock_data(,zget_space_lock)
-vm_offset_t zalloc_next_space;
-vm_offset_t zalloc_end_of_space;
-vm_size_t zalloc_wasted_space;
+#if KASAN_ZALLOC
+#define MAX_ZONES 566
+#else /* !KASAN_ZALLOC */
+#define MAX_ZONES 402
+#endif/* !KASAN_ZALLOC */
/*
- * Garbage collection map information
+ * Initial globals for zone stats until we can allocate the real ones.
+ * Those get migrated inside the per-CPU ones during zone_init() and
+ * this array is unmapped with the rest of __startup_data at lockdown.
*/
-struct zone_page_table_entry * zone_page_table;
-vm_offset_t zone_map_min_address;
-vm_offset_t zone_map_max_address;
-unsigned int zone_pages;
+/* zone to allocate zone_magazine structs from */
+static SECURITY_READ_ONLY_LATE(zone_t) zc_magazine_zone;
/*
- * Exclude more than one concurrent garbage collection
+ * Until pid1 is made, zone caching is off,
+ * until compute_zone_working_set_size() runs for the firt time.
+ *
+ * -1 represents the "never enabled yet" value.
*/
-decl_mutex_data(, zone_gc_lock)
+static int8_t zone_caching_disabled = -1;
-#define from_zone_map(addr, size) \
- ((vm_offset_t)(addr) >= zone_map_min_address && \
- ((vm_offset_t)(addr) + size -1) < zone_map_max_address)
+__startup_data
+static struct zone_cache zone_cache_startup[MAX_ZONES];
+__startup_data
+static struct zone_stats zone_stats_startup[MAX_ZONES];
+struct zone zone_array[MAX_ZONES];
-#define ZONE_PAGE_USED 0
-#define ZONE_PAGE_UNUSED -1
+/* Initialized in zone_bootstrap(), how many "copies" the per-cpu system does */
+static SECURITY_READ_ONLY_LATE(unsigned) zpercpu_early_count;
+/* Used to keep track of destroyed slots in the zone_array */
+static bitmap_t zone_destroyed_bitmap[BITMAP_LEN(MAX_ZONES)];
+
+/* number of zone mapped pages used by all zones */
+static long _Atomic zones_phys_page_mapped_count;
/*
- * Protects first_zone, last_zone, num_zones,
- * and the next_zone field of zones.
+ * Turn ZSECURITY_OPTIONS_STRICT_IOKIT_FREE off on x86 so as not
+ * not break third party kexts that haven't yet been recompiled
+ * to use the new iokit macros.
*/
-decl_simple_lock_data(, all_zones_lock)
-zone_t first_zone;
-zone_t *last_zone;
-unsigned int num_zones;
+#if XNU_TARGET_OS_OSX && __x86_64__
+#define ZSECURITY_OPTIONS_STRICT_IOKIT_FREE_DEFAULT 0
+#else
+#define ZSECURITY_OPTIONS_STRICT_IOKIT_FREE_DEFAULT \
+ ZSECURITY_OPTIONS_STRICT_IOKIT_FREE
+#endif
+
+#define ZSECURITY_DEFAULT ( \
+ ZSECURITY_OPTIONS_SEQUESTER | \
+ ZSECURITY_OPTIONS_SUBMAP_USER_DATA | \
+ ZSECURITY_OPTIONS_SEQUESTER_KEXT_KALLOC | \
+ ZSECURITY_OPTIONS_STRICT_IOKIT_FREE_DEFAULT | \
+ 0)
+TUNABLE(zone_security_options_t, zsecurity_options, "zs", ZSECURITY_DEFAULT);
+
+#if VM_MAX_TAG_ZONES
+/* enable tags for zones that ask for it */
+static TUNABLE(bool, zone_tagging_on, "-zt", false);
+#endif /* VM_MAX_TAG_ZONES */
+
+#if DEBUG || DEVELOPMENT
+TUNABLE(bool, zalloc_disable_copyio_check, "-no-copyio-zalloc-check", false);
+#endif /* DEBUG || DEVELOPMENT */
+#if CONFIG_ZLEAKS
+/* Making pointer scanning leaks detection possible for all zones */
+static TUNABLE(bool, zone_leaks_scan_enable, "-zl", false);
+#else
+#define zone_leaks_scan_enable false
+#endif
-boolean_t zone_gc_allowed = TRUE;
-boolean_t zone_gc_forced = FALSE;
-unsigned zone_gc_last_tick = 0;
-unsigned zone_gc_max_rate = 0; /* in ticks */
+/*! @enum zprot_mode_t
+ *
+ * @brief
+ * Zone element corruption detection mode.
+ *
+ * @discussion
+ * We use four techniques to detect modification of a zone element
+ * after it's been freed.
+ *
+ * Elements that are in zones can be in 3 possible states:
+ * - zeroed out (@c ZPM_ZERO)
+ * - poisoned (@c ZPM_POISON) with the @c ZONE_POISON pattern
+ * - with a left and right canary (@c ZPM_CANARY).
+ *
+ * @c ZPM_AUTO is used when the actual protection for the element is unknown,
+ * and will be detected looking at the last word of the allocation at validation
+ * time.
+ *
+ * The mode of an element in zones is discovered by looking at its last
+ * pointer-sized value:
+ * - 0 means that it is zeroed out
+ * - @c ZONE_POISON means it is poisoned
+ * - any other value means it is using canaries.
+ *
+ * Elements are zeroed if:
+ * - the element size is smaller than @c zp_min_size,
+ * - the owning zone has the @c z_free_zeroes flag set,
+ * - the chunk backing store is fresh (and was just allocated).
+ *
+ * Elements are poisoned periodically for every N frees (counted per-zone),
+ * if the elements aren't otherwise zeroed out.
+ * If -zp is passed as a boot arg, poisoning occurs for every free.
+ *
+ * Else elements use canaries. When canaries are used, the first and last
+ * pointer sized values in the allocation are set to values derived from the
+ * element address and the @c zp_canary nonce. The first @c zp_min_size
+ * bytes of the elment are also cleared.
+ *
+ * Performance slowdown is inversely proportional to the frequency of poisoning,
+ * with a 4-5% hit around N=1, down to ~0.3% at N=16 and just "noise" at N=32
+ * and higher. You can expect to find a 100% reproducible bug in an average of
+ * N tries, with a standard deviation of about N, but you will want to set
+ * "-zp" to always poison every free if you are attempting to reproduce
+ * a known bug.
+ *
+ * For a more heavyweight, but finer-grained method of detecting misuse
+ * of zone memory, look up the "Guard mode" zone allocator in gzalloc.c.
+ */
+__enum_closed_decl(zprot_mode_t, vm_offset_t, {
+ ZPM_AUTO, /* element is indeterminate */
+ ZPM_ZERO, /* element is zeroed */
+ ZPM_POISON, /* element is poisoned */
+ ZPM_CANARY, /* element extremities have a canary */
+});
+#define ZPM_MASK ((zprot_mode_t)0x3)
/*
- * zinit initializes a new zone. The zone data structures themselves
- * are stored in a zone, which is initially a static structure that
- * is initialized by zone_init.
+ * set by zp-factor=N boot arg
+ *
+ * A zp_factor of 0 indicates zone poisoning is disabled and can also be set by
+ * passing the -no-zp boot-arg.
+ *
+ * A zp_factor of 1 indicates zone poisoning is on for all elements and can be
+ * set by passing the -zp boot-arg.
*/
-zone_t
-zinit(
- vm_size_t size, /* the size of an element */
- vm_size_t max, /* maximum memory to use */
- vm_size_t alloc, /* allocation size */
- const char *name) /* a name for the zone */
-{
- zone_t z;
-
- if (zone_zone == ZONE_NULL) {
- if (zget_space(sizeof(struct zone), (vm_offset_t *)&z)
- != KERN_SUCCESS)
- return(ZONE_NULL);
- } else
- z = (zone_t) zalloc(zone_zone);
- if (z == ZONE_NULL)
- return(ZONE_NULL);
-
- /*
- * Round off all the parameters appropriately.
- */
- if (size < sizeof(z->free_elements))
- size = sizeof(z->free_elements);
- size = ((size-1) + sizeof(z->free_elements)) -
- ((size-1) % sizeof(z->free_elements));
- if (alloc == 0)
- alloc = PAGE_SIZE;
- alloc = round_page(alloc);
- max = round_page(max);
- /*
- * we look for an allocation size with less than 1% waste
- * up to 5 pages in size...
- * otherwise, we look for an allocation size with least fragmentation
- * in the range of 1 - 5 pages
- * This size will be used unless
- * the user suggestion is larger AND has less fragmentation
- */
- { vm_size_t best, waste; unsigned int i;
- best = PAGE_SIZE;
- waste = best % size;
-
- for (i = 1; i <= 5; i++) {
- vm_size_t tsize, twaste;
-
- tsize = i * PAGE_SIZE;
-
- if ((tsize % size) < (tsize / 100)) {
- alloc = tsize;
- goto use_this_allocation;
- }
- twaste = tsize % size;
- if (twaste < waste)
- best = tsize, waste = twaste;
- }
- if (alloc <= best || (alloc % size >= waste))
- alloc = best;
- }
-use_this_allocation:
- if (max && (max < alloc))
- max = alloc;
-
- z->free_elements = 0;
- z->cur_size = 0;
- z->max_size = max;
- z->elem_size = size;
- z->alloc_size = alloc;
- z->zone_name = name;
- z->count = 0;
- z->doing_alloc = FALSE;
- z->doing_gc = FALSE;
- z->exhaustible = FALSE;
- z->collectable = TRUE;
- z->allows_foreign = FALSE;
- z->expandable = TRUE;
- z->waiting = FALSE;
- z->async_pending = FALSE;
-
-#if ZONE_DEBUG
- z->active_zones.next = z->active_zones.prev = 0;
- zone_debug_enable(z);
-#endif /* ZONE_DEBUG */
- lock_zone_init(z);
-
- /*
- * Add the zone to the all-zones list.
- */
-
- z->next_zone = ZONE_NULL;
- thread_call_setup(&z->call_async_alloc, zalloc_async, z);
- simple_lock(&all_zones_lock);
- *last_zone = z;
- last_zone = &z->next_zone;
- num_zones++;
- simple_unlock(&all_zones_lock);
+static TUNABLE(uint32_t, zp_factor, "zp-factor", 16);
- return(z);
-}
+/* set by zp-scale=N boot arg, scales zp_factor by zone size */
+static TUNABLE(uint32_t, zp_scale, "zp-scale", 4);
/*
- * Cram the given memory into the specified zone.
+ * Zone caching tunables
+ *
+ * zc_mag_size():
+ * size of magazines, larger to reduce contention at the expense of memory
+ *
+ * zc_auto_enable_threshold
+ * number of contentions per second after which zone caching engages
+ * automatically.
+ *
+ * 0 to disable.
+ *
+ * zc_grow_threshold
+ * numer of contentions per second after which the per-cpu depot layer
+ * grows at each newly observed contention without restriction.
+ *
+ * 0 to disable.
+ *
+ * zc_recirc_denom
+ * denominator of the fraction of per-cpu depot to migrate to/from
+ * the recirculation depot layer at a time. Default 3 (1/3).
+ *
+ * zc_defrag_ratio
+ * percentage of the working set to recirc size below which
+ * the zone is defragmented. Default is 50%.
+ *
+ * zc_free_batch_size
+ * The size of batches of frees/reclaim that can be done keeping
+ * the zone lock held (and preemption disabled).
+ */
+static TUNABLE(uint16_t, zc_magazine_size, "zc_mag_size()", 8);
+static TUNABLE(uint32_t, zc_auto_threshold, "zc_auto_enable_threshold", 20);
+static TUNABLE(uint32_t, zc_grow_threshold, "zc_grow_threshold", 8);
+static TUNABLE(uint32_t, zc_recirc_denom, "zc_recirc_denom", 3);
+static TUNABLE(uint32_t, zc_defrag_ratio, "zc_defrag_ratio", 50);
+static TUNABLE(uint32_t, zc_free_batch_size, "zc_free_batch_size", 1024);
+
+static SECURITY_READ_ONLY_LATE(uintptr_t) zp_canary;
+/*
+ * Perf results for zeroing all non data zones and 2K of data zones
+ * showed little regression, therefore setting zp_min_size to 2048
*/
-void
-zcram(
- register zone_t zone,
- void *newaddr,
- vm_size_t size)
-{
- register vm_size_t elem_size;
- vm_offset_t newmem = (vm_offset_t) newaddr;
+static TUNABLE(uint32_t, zp_min_size, "zclear_size", 2048);
+static SECURITY_READ_ONLY_LATE(uint32_t) zone_phys_mapped_max_pages;
+static SECURITY_READ_ONLY_LATE(vm_map_t) zone_submaps[Z_SUBMAP_IDX_COUNT];
+static SECURITY_READ_ONLY_LATE(uint32_t) zone_last_submap_idx;
- /* Basic sanity checks */
- assert(zone != ZONE_NULL && newmem != (vm_offset_t)0);
- assert(!zone->collectable || zone->allows_foreign
- || (from_zone_map(newmem, size)));
+static zone_t zone_find_largest(void);
- elem_size = zone->elem_size;
+#endif /* !ZALLOC_TEST */
+#pragma mark Zone metadata
+#if !ZALLOC_TEST
- lock_zone(zone);
- while (size >= elem_size) {
- ADD_TO_ZONE(zone, newmem);
- if (from_zone_map(newmem, elem_size))
- zone_page_alloc(newmem, elem_size);
- zone->count++; /* compensate for ADD_TO_ZONE */
- size -= elem_size;
- newmem += elem_size;
- zone->cur_size += elem_size;
- }
- unlock_zone(zone);
+static inline zone_id_t
+zone_index(zone_t z)
+{
+ return (zone_id_t)(z - zone_array);
}
-/*
- * Contiguous space allocator for non-paged zones. Allocates "size" amount
- * of memory from zone_map.
- */
-
-kern_return_t
-zget_space(
- vm_offset_t size,
- vm_offset_t *result)
+static inline bool
+zone_has_index(zone_t z, zone_id_t zid)
{
- vm_offset_t new_space = 0;
- vm_size_t space_to_add = 0;
-
- simple_lock(&zget_space_lock);
- while ((zalloc_next_space + size) > zalloc_end_of_space) {
- /*
- * Add at least one page to allocation area.
- */
+ return zone_array + zid == z;
+}
- space_to_add = round_page(size);
+static zone_element_t
+zone_element_encode(vm_offset_t base, vm_offset_t eidx, zprot_mode_t zpm)
+{
+ return (zone_element_t){ .ze_value = base | (eidx << 2) | zpm };
+}
- if (new_space == 0) {
- kern_return_t retval;
- /*
- * Memory cannot be wired down while holding
- * any locks that the pageout daemon might
- * need to free up pages. [Making the zget_space
- * lock a complex lock does not help in this
- * regard.]
- *
- * Unlock and allocate memory. Because several
- * threads might try to do this at once, don't
- * use the memory before checking for available
- * space again.
- */
+static vm_offset_t
+zone_element_base(zone_element_t ze)
+{
+ return trunc_page(ze.ze_value);
+}
- simple_unlock(&zget_space_lock);
+static vm_offset_t
+zone_element_idx(zone_element_t ze)
+{
+ return (ze.ze_value & PAGE_MASK) >> 2;
+}
- retval = kernel_memory_allocate(zone_map, &new_space,
- space_to_add, 0, KMA_KOBJECT|KMA_NOPAGEWAIT);
- if (retval != KERN_SUCCESS)
- return(retval);
- zone_page_init(new_space, space_to_add,
- ZONE_PAGE_USED);
- simple_lock(&zget_space_lock);
- continue;
- }
+#if ZALLOC_ENABLE_POISONING
+static zprot_mode_t
+zone_element_prot(zone_element_t ze)
+{
+ return (zprot_mode_t)(ze.ze_value & ZPM_MASK);
+}
+#endif
-
- /*
- * Memory was allocated in a previous iteration.
- *
- * Check whether the new region is contiguous
- * with the old one.
- */
+static vm_offset_t
+zone_element_addr(zone_element_t ze, vm_offset_t esize)
+{
+ return zone_element_base(ze) + esize * zone_element_idx(ze);
+}
- if (new_space != zalloc_end_of_space) {
- /*
- * Throw away the remainder of the
- * old space, and start a new one.
- */
- zalloc_wasted_space +=
- zalloc_end_of_space - zalloc_next_space;
- zalloc_next_space = new_space;
- }
+__abortlike
+static void
+zone_metadata_corruption(zone_t zone, struct zone_page_metadata *meta,
+ const char *kind)
+{
+ panic("zone metadata corruption: %s (meta %p, zone %s%s)",
+ kind, meta, zone_heap_name(zone), zone->z_name);
+}
- zalloc_end_of_space = new_space + space_to_add;
+__abortlike
+static void
+zone_invalid_element_addr_panic(zone_t zone, vm_offset_t addr)
+{
+ panic("zone element pointer validation failed (addr: %p, zone %s%s)",
+ (void *)addr, zone_heap_name(zone), zone->z_name);
+}
- new_space = 0;
- }
- *result = zalloc_next_space;
- zalloc_next_space += size;
- simple_unlock(&zget_space_lock);
+__abortlike
+static void
+zone_invalid_element_panic(zone_t zone, zone_element_t ze)
+{
+ panic("zone element pointer validation failed (elem: %p,%d, zone %s%s)",
+ (void *)zone_element_base(ze), (int)zone_element_idx(ze),
+ zone_heap_name(zone), zone->z_name);
+}
- if (new_space != 0)
- kmem_free(zone_map, new_space, space_to_add);
+__abortlike
+static void
+zone_page_metadata_index_confusion_panic(zone_t zone, vm_offset_t addr,
+ struct zone_page_metadata *meta)
+{
+ panic("%p not in the expected zone %s%s (%d != %d)",
+ (void *)addr, zone_heap_name(zone), zone->z_name,
+ meta->zm_index, zone_index(zone));
+}
- return(KERN_SUCCESS);
+__abortlike
+static void
+zone_page_metadata_native_queue_corruption(zone_t zone, zone_pva_t *queue)
+{
+ panic("foreign metadata index %d enqueued in native head %p from zone %s%s",
+ queue->packed_address, queue, zone_heap_name(zone),
+ zone->z_name);
}
+__abortlike
+static void
+zone_page_metadata_list_corruption(zone_t zone, struct zone_page_metadata *meta)
+{
+ panic("metadata list corruption through element %p detected in zone %s%s",
+ meta, zone_heap_name(zone), zone->z_name);
+}
-/*
- * Steal memory for the zone package. Called from
- * vm_page_bootstrap().
- */
-void
-zone_steal_memory(void)
+__abortlike __unused
+static void
+zone_invalid_foreign_addr_panic(zone_t zone, vm_offset_t addr)
{
- zdata_size = round_page(128*sizeof(struct zone));
- zdata = (vm_offset_t)((char *)pmap_steal_memory(zdata_size) - (char *)0);
+ panic("addr %p being freed to foreign zone %s%s not from foreign range",
+ (void *)addr, zone_heap_name(zone), zone->z_name);
}
+__abortlike
+static void
+zone_page_meta_accounting_panic(zone_t zone, struct zone_page_metadata *meta,
+ const char *kind)
+{
+ panic("accounting mismatch (%s) for zone %s%s, meta %p", kind,
+ zone_heap_name(zone), zone->z_name, meta);
+}
-/*
- * Fill a zone with enough memory to contain at least nelem elements.
- * Memory is obtained with kmem_alloc_wired from the kernel_map.
- * Return the number of elements actually put into the zone, which may
- * be more than the caller asked for since the memory allocation is
- * rounded up to a full page.
- */
-int
-zfill(
- zone_t zone,
- int nelem)
+__abortlike
+static void
+zone_meta_double_free_panic(zone_t zone, zone_element_t ze, const char *caller)
{
- kern_return_t kr;
- vm_size_t size;
- vm_offset_t memory;
- int nalloc;
+ panic("%s: double free of %p to zone %s%s", caller,
+ (void *)zone_element_addr(ze, zone_elem_size(zone)),
+ zone_heap_name(zone), zone->z_name);
+}
- assert(nelem > 0);
- if (nelem <= 0)
- return 0;
- size = nelem * zone->elem_size;
- size = round_page(size);
- kr = kmem_alloc_wired(kernel_map, &memory, size);
- if (kr != KERN_SUCCESS)
- return 0;
+__abortlike
+static void
+zone_accounting_panic(zone_t zone, const char *kind)
+{
+ panic("accounting mismatch (%s) for zone %s%s", kind,
+ zone_heap_name(zone), zone->z_name);
+}
- zone_change(zone, Z_FOREIGN, TRUE);
- zcram(zone, (void *)memory, size);
- nalloc = size / zone->elem_size;
- assert(nalloc >= nelem);
+#define zone_counter_sub(z, stat, value) ({ \
+ if (os_sub_overflow((z)->stat, value, &(z)->stat)) { \
+ zone_accounting_panic(z, #stat " wrap-around"); \
+ } \
+ (z)->stat; \
+})
- return nalloc;
+static inline void
+zone_elems_free_add(zone_t z, uint32_t count)
+{
+ uint32_t n = (z->z_elems_free += count);
+ if (z->z_elems_free_max < n) {
+ z->z_elems_free_max = n;
+ }
}
-/*
- * Initialize the "zone of zones" which uses fixed memory allocated
- * earlier in memory initialization. zone_bootstrap is called
- * before zone_init.
- */
-void
-zone_bootstrap(void)
+static inline void
+zone_elems_free_sub(zone_t z, uint32_t count)
{
- vm_size_t zone_zone_size;
- vm_offset_t zone_zone_space;
+ uint32_t n = zone_counter_sub(z, z_elems_free, count);
- simple_lock_init(&all_zones_lock, 0);
-
- first_zone = ZONE_NULL;
- last_zone = &first_zone;
- num_zones = 0;
+ if (z->z_elems_free_min > n) {
+ z->z_elems_free_min = n;
+ }
+}
- simple_lock_init(&zget_space_lock, 0);
- zalloc_next_space = zdata;
- zalloc_end_of_space = zdata + zdata_size;
- zalloc_wasted_space = 0;
+static inline uint16_t
+zone_meta_alloc_size_add(zone_t z, struct zone_page_metadata *m,
+ vm_offset_t esize)
+{
+ if (os_add_overflow(m->zm_alloc_size, (uint16_t)esize, &m->zm_alloc_size)) {
+ zone_page_meta_accounting_panic(z, m, "alloc_size wrap-around");
+ }
+ return m->zm_alloc_size;
+}
- /* assertion: nobody else called zinit before us */
- assert(zone_zone == ZONE_NULL);
- zone_zone = zinit(sizeof(struct zone), 128 * sizeof(struct zone),
- sizeof(struct zone), "zones");
- zone_change(zone_zone, Z_COLLECT, FALSE);
- zone_zone_size = zalloc_end_of_space - zalloc_next_space;
- zget_space(zone_zone_size, &zone_zone_space);
- zcram(zone_zone, (void *)zone_zone_space, zone_zone_size);
+static inline uint16_t
+zone_meta_alloc_size_sub(zone_t z, struct zone_page_metadata *m,
+ vm_offset_t esize)
+{
+ if (os_sub_overflow(m->zm_alloc_size, esize, &m->zm_alloc_size)) {
+ zone_page_meta_accounting_panic(z, m, "alloc_size wrap-around");
+ }
+ return m->zm_alloc_size;
}
-void
-zone_init(
- vm_size_t max_zonemap_size)
+__abortlike
+static void
+zone_nofail_panic(zone_t zone)
{
- kern_return_t retval;
- vm_offset_t zone_min;
- vm_offset_t zone_max;
- vm_size_t zone_table_size;
+ panic("zalloc(Z_NOFAIL) can't be satisfied for zone %s%s (potential leak)",
+ zone_heap_name(zone), zone->z_name);
+}
- retval = kmem_suballoc(kernel_map, &zone_min, max_zonemap_size,
- FALSE, VM_FLAGS_ANYWHERE, &zone_map);
+#if __arm64__
+// <rdar://problem/48304934> arm64 doesn't use ldp when I'd expect it to
+#define zone_range_load(r, rmin, rmax) \
+ asm("ldp %[rmin], %[rmax], [%[range]]" \
+ : [rmin] "=r"(rmin), [rmax] "=r"(rmax) \
+ : [range] "r"(r))
+#else
+#define zone_range_load(r, rmin, rmax) \
+ ({ rmin = (r)->min_address; rmax = (r)->max_address; })
+#endif
+
+__header_always_inline bool
+zone_range_contains(const struct zone_map_range *r, vm_offset_t addr, vm_offset_t size)
+{
+ vm_offset_t rmin, rmax;
- if (retval != KERN_SUCCESS)
- panic("zone_init: kmem_suballoc failed");
- zone_max = zone_min + round_page(max_zonemap_size);
/*
- * Setup garbage collection information:
+ * The `&` is not a typo: we really expect the check to pass,
+ * so encourage the compiler to eagerly load and test without branches
*/
- zone_table_size = atop_32(zone_max - zone_min) *
- sizeof(struct zone_page_table_entry);
- if (kmem_alloc_wired(zone_map, (vm_offset_t *) &zone_page_table,
- zone_table_size) != KERN_SUCCESS)
- panic("zone_init");
- zone_min = (vm_offset_t)zone_page_table + round_page(zone_table_size);
- zone_pages = atop_32(zone_max - zone_min);
- zone_map_min_address = zone_min;
- zone_map_max_address = zone_max;
- mutex_init(&zone_gc_lock, 0);
- zone_page_init(zone_min, zone_max - zone_min, ZONE_PAGE_UNUSED);
+ zone_range_load(r, rmin, rmax);
+ return (addr >= rmin) & (addr + size >= rmin) & (addr + size <= rmax);
}
-
-/*
- * zalloc returns an element from the specified zone.
- */
-void *
-zalloc_canblock(
- register zone_t zone,
- boolean_t canblock)
+__header_always_inline vm_size_t
+zone_range_size(const struct zone_map_range *r)
{
- vm_offset_t addr;
- kern_return_t retval;
+ vm_offset_t rmin, rmax;
- assert(zone != ZONE_NULL);
+ zone_range_load(r, rmin, rmax);
+ return rmax - rmin;
+}
- lock_zone(zone);
+#define from_zone_map(addr, size, kind) \
+ zone_range_contains(&zone_info.zi_map_range[kind], \
+ (vm_offset_t)(addr), size)
- REMOVE_FROM_ZONE(zone, addr, vm_offset_t);
+#define zone_native_size() \
+ zone_range_size(&zone_info.zi_map_range[ZONE_ADDR_NATIVE])
- while ((addr == 0) && canblock && (zone->doing_gc)) {
- zone->waiting = TRUE;
- zone_sleep(zone);
- REMOVE_FROM_ZONE(zone, addr, vm_offset_t);
- }
+#define zone_foreign_size() \
+ zone_range_size(&zone_info.zi_map_range[ZONE_ADDR_FOREIGN])
- while ((addr == 0) && canblock) {
- /*
- * If nothing was there, try to get more
- */
- if (zone->doing_alloc) {
- /*
- * Someone is allocating memory for this zone.
- * Wait for it to show up, then try again.
- */
- zone->waiting = TRUE;
- zone_sleep(zone);
- }
- else {
- if ((zone->cur_size + zone->elem_size) >
- zone->max_size) {
- if (zone->exhaustible)
- break;
- if (zone->expandable) {
- /*
- * We're willing to overflow certain
- * zones, but not without complaining.
- *
- * This is best used in conjunction
- * with the collectable flag. What we
- * want is an assurance we can get the
- * memory back, assuming there's no
- * leak.
- */
- zone->max_size += (zone->max_size >> 1);
- } else {
- unlock_zone(zone);
-
- panic("zalloc: zone \"%s\" empty.", zone->zone_name);
- }
- }
- zone->doing_alloc = TRUE;
- unlock_zone(zone);
-
- if (zone->collectable) {
- vm_offset_t space;
- vm_size_t alloc_size;
- boolean_t retry = FALSE;
-
- for (;;) {
-
- if (vm_pool_low() || retry == TRUE)
- alloc_size =
- round_page(zone->elem_size);
- else
- alloc_size = zone->alloc_size;
-
- retval = kernel_memory_allocate(zone_map,
- &space, alloc_size, 0,
- KMA_KOBJECT|KMA_NOPAGEWAIT);
- if (retval == KERN_SUCCESS) {
- zone_page_init(space, alloc_size,
- ZONE_PAGE_USED);
- zcram(zone, (void *)space, alloc_size);
-
- break;
- } else if (retval != KERN_RESOURCE_SHORTAGE) {
- /* would like to cause a zone_gc() */
- if (retry == TRUE)
- panic("zalloc: \"%s\" (%d elements) retry fail %d", zone->zone_name, zone->count, retval);
- retry = TRUE;
- } else {
- break;
- }
- }
- lock_zone(zone);
- zone->doing_alloc = FALSE;
- if (zone->waiting) {
- zone->waiting = FALSE;
- zone_wakeup(zone);
- }
- REMOVE_FROM_ZONE(zone, addr, vm_offset_t);
- if (addr == 0 &&
- retval == KERN_RESOURCE_SHORTAGE) {
- unlock_zone(zone);
-
- VM_PAGE_WAIT();
- lock_zone(zone);
- }
- } else {
- vm_offset_t space;
- retval = zget_space(zone->elem_size, &space);
-
- lock_zone(zone);
- zone->doing_alloc = FALSE;
- if (zone->waiting) {
- zone->waiting = FALSE;
- thread_wakeup((event_t)zone);
- }
- if (retval == KERN_SUCCESS) {
- zone->count++;
- zone->cur_size += zone->elem_size;
-#if ZONE_DEBUG
- if (zone_debug_enabled(zone)) {
- enqueue_tail(&zone->active_zones, (queue_entry_t)space);
- }
-#endif
- unlock_zone(zone);
- zone_page_alloc(space, zone->elem_size);
-#if ZONE_DEBUG
- if (zone_debug_enabled(zone))
- space += ZONE_DEBUG_OFFSET;
-#endif
- return((void *)space);
- }
- if (retval == KERN_RESOURCE_SHORTAGE) {
- unlock_zone(zone);
-
- VM_PAGE_WAIT();
- lock_zone(zone);
- } else {
- panic("zalloc: \"%s\" (%d elements) zget_space returned %d", zone->zone_name, zone->count, retval);
- }
- }
- }
- if (addr == 0)
- REMOVE_FROM_ZONE(zone, addr, vm_offset_t);
- }
+__header_always_inline bool
+zone_pva_is_null(zone_pva_t page)
+{
+ return page.packed_address == 0;
+}
- if ((addr == 0) && !canblock && (zone->async_pending == FALSE) && (!vm_pool_low())) {
- zone->async_pending = TRUE;
- unlock_zone(zone);
- thread_call_enter(&zone->call_async_alloc);
- lock_zone(zone);
- REMOVE_FROM_ZONE(zone, addr, vm_offset_t);
- }
+__header_always_inline bool
+zone_pva_is_queue(zone_pva_t page)
+{
+ // actual kernel pages have the top bit set
+ return (int32_t)page.packed_address > 0;
+}
-#if ZONE_DEBUG
- if (addr && zone_debug_enabled(zone)) {
- enqueue_tail(&zone->active_zones, (queue_entry_t)addr);
- addr += ZONE_DEBUG_OFFSET;
- }
-#endif
+__header_always_inline bool
+zone_pva_is_equal(zone_pva_t pva1, zone_pva_t pva2)
+{
+ return pva1.packed_address == pva2.packed_address;
+}
- unlock_zone(zone);
+__header_always_inline void
+zone_queue_set_head(zone_t z, zone_pva_t queue, zone_pva_t oldv,
+ struct zone_page_metadata *meta)
+{
+ zone_pva_t *queue_head = &((zone_pva_t *)zone_array)[queue.packed_address];
- return((void *)addr);
+ if (!zone_pva_is_equal(*queue_head, oldv)) {
+ zone_page_metadata_list_corruption(z, meta);
+ }
+ *queue_head = meta->zm_page_next;
}
-
-void *
-zalloc(
- register zone_t zone)
+__header_always_inline zone_pva_t
+zone_queue_encode(zone_pva_t *headp)
{
- return( zalloc_canblock(zone, TRUE) );
+ return (zone_pva_t){ (uint32_t)(headp - (zone_pva_t *)zone_array) };
}
-void *
-zalloc_noblock(
- register zone_t zone)
+__header_always_inline zone_pva_t
+zone_pva_from_addr(vm_address_t addr)
{
- return( zalloc_canblock(zone, FALSE) );
+ // cannot use atop() because we want to maintain the sign bit
+ return (zone_pva_t){ (uint32_t)((intptr_t)addr >> PAGE_SHIFT) };
}
-void
-zalloc_async(
- thread_call_param_t p0,
- __unused thread_call_param_t p1)
+__header_always_inline zone_pva_t
+zone_pva_from_element(zone_element_t ze)
{
- void *elt;
-
- elt = zalloc_canblock((zone_t)p0, TRUE);
- zfree((zone_t)p0, elt);
- lock_zone(((zone_t)p0));
- ((zone_t)p0)->async_pending = FALSE;
- unlock_zone(((zone_t)p0));
+ return zone_pva_from_addr(ze.ze_value);
}
-
-/*
- * zget returns an element from the specified zone
- * and immediately returns nothing if there is nothing there.
- *
- * This form should be used when you can not block (like when
- * processing an interrupt).
- */
-void *
-zget(
- register zone_t zone)
+__header_always_inline vm_address_t
+zone_pva_to_addr(zone_pva_t page)
{
- register vm_offset_t addr;
+ // cause sign extension so that we end up with the right address
+ return (vm_offset_t)(int32_t)page.packed_address << PAGE_SHIFT;
+}
- assert( zone != ZONE_NULL );
+__header_always_inline struct zone_page_metadata *
+zone_pva_to_meta(zone_pva_t page)
+{
+ return &zone_info.zi_meta_base[page.packed_address];
+}
- if (!lock_try_zone(zone))
- return NULL;
+__header_always_inline zone_pva_t
+zone_pva_from_meta(struct zone_page_metadata *meta)
+{
+ return (zone_pva_t){ (uint32_t)(meta - zone_info.zi_meta_base) };
+}
- REMOVE_FROM_ZONE(zone, addr, vm_offset_t);
-#if ZONE_DEBUG
- if (addr && zone_debug_enabled(zone)) {
- enqueue_tail(&zone->active_zones, (queue_entry_t)addr);
- addr += ZONE_DEBUG_OFFSET;
- }
-#endif /* ZONE_DEBUG */
- unlock_zone(zone);
+__header_always_inline struct zone_page_metadata *
+zone_meta_from_addr(vm_offset_t addr)
+{
+ return zone_pva_to_meta(zone_pva_from_addr(addr));
+}
- return((void *) addr);
+__header_always_inline struct zone_page_metadata *
+zone_meta_from_element(zone_element_t ze)
+{
+ return zone_pva_to_meta(zone_pva_from_element(ze));
}
-/* Keep this FALSE by default. Large memory machine run orders of magnitude
- slower in debug mode when true. Use debugger to enable if needed */
-/* static */ boolean_t zone_check = FALSE;
-
-static zone_t zone_last_bogus_zone = ZONE_NULL;
-static vm_offset_t zone_last_bogus_elem = 0;
+__header_always_inline zone_id_t
+zone_index_from_ptr(const void *ptr)
+{
+ return zone_pva_to_meta(zone_pva_from_addr((vm_offset_t)ptr))->zm_index;
+}
-void
-zfree(
- register zone_t zone,
- void *addr)
-{
- vm_offset_t elem = (vm_offset_t) addr;
-
-#if MACH_ASSERT
- /* Basic sanity checks */
- if (zone == ZONE_NULL || elem == (vm_offset_t)0)
- panic("zfree: NULL");
- /* zone_gc assumes zones are never freed */
- if (zone == zone_zone)
- panic("zfree: freeing to zone_zone breaks zone_gc!");
-#endif
+__header_always_inline vm_offset_t
+zone_meta_to_addr(struct zone_page_metadata *meta)
+{
+ return ptoa((int32_t)(meta - zone_info.zi_meta_base));
+}
- if (zone->collectable && !zone->allows_foreign &&
- !from_zone_map(elem, zone->elem_size)) {
-#if MACH_ASSERT
- panic("zfree: non-allocated memory in collectable zone!");
-#endif
- zone_last_bogus_zone = zone;
- zone_last_bogus_elem = elem;
- return;
+__header_always_inline void
+zone_meta_queue_push(zone_t z, zone_pva_t *headp,
+ struct zone_page_metadata *meta)
+{
+ zone_pva_t head = *headp;
+ zone_pva_t queue_pva = zone_queue_encode(headp);
+ struct zone_page_metadata *tmp;
+
+ meta->zm_page_next = head;
+ if (!zone_pva_is_null(head)) {
+ tmp = zone_pva_to_meta(head);
+ if (!zone_pva_is_equal(tmp->zm_page_prev, queue_pva)) {
+ zone_page_metadata_list_corruption(z, meta);
+ }
+ tmp->zm_page_prev = zone_pva_from_meta(meta);
}
+ meta->zm_page_prev = queue_pva;
+ *headp = zone_pva_from_meta(meta);
+}
- lock_zone(zone);
-#if ZONE_DEBUG
- if (zone_debug_enabled(zone)) {
- queue_t tmp_elem;
+__header_always_inline struct zone_page_metadata *
+zone_meta_queue_pop_native(zone_t z, zone_pva_t *headp, vm_offset_t *page_addrp)
+{
+ zone_pva_t head = *headp;
+ struct zone_page_metadata *meta = zone_pva_to_meta(head);
+ vm_offset_t page_addr = zone_pva_to_addr(head);
+ struct zone_page_metadata *tmp;
- elem -= ZONE_DEBUG_OFFSET;
- if (zone_check) {
- /* check the zone's consistency */
+ if (!from_zone_map(page_addr, 1, ZONE_ADDR_NATIVE)) {
+ zone_page_metadata_native_queue_corruption(z, headp);
+ }
- for (tmp_elem = queue_first(&zone->active_zones);
- !queue_end(tmp_elem, &zone->active_zones);
- tmp_elem = queue_next(tmp_elem))
- if (elem == (vm_offset_t)tmp_elem)
- break;
- if (elem != (vm_offset_t)tmp_elem)
- panic("zfree()ing element from wrong zone");
+ if (!zone_pva_is_null(meta->zm_page_next)) {
+ tmp = zone_pva_to_meta(meta->zm_page_next);
+ if (!zone_pva_is_equal(tmp->zm_page_prev, head)) {
+ zone_page_metadata_list_corruption(z, meta);
}
- remqueue(&zone->active_zones, (queue_t) elem);
+ tmp->zm_page_prev = meta->zm_page_prev;
}
-#endif /* ZONE_DEBUG */
- if (zone_check) {
- vm_offset_t this;
+ *headp = meta->zm_page_next;
- /* check the zone's consistency */
+ meta->zm_page_next = meta->zm_page_prev = (zone_pva_t){ 0 };
+ *page_addrp = page_addr;
- for (this = zone->free_elements;
- this != 0;
- this = * (vm_offset_t *) this)
- if (!pmap_kernel_va(this) || this == elem)
- panic("zfree");
+ if (!zone_has_index(z, meta->zm_index)) {
+ zone_page_metadata_index_confusion_panic(z,
+ zone_meta_to_addr(meta), meta);
}
- ADD_TO_ZONE(zone, elem);
+ return meta;
+}
- /*
- * If elements have one or more pages, and memory is low,
- * request to run the garbage collection in the zone the next
- * time the pageout thread runs.
- */
- if (zone->elem_size >= PAGE_SIZE &&
- vm_pool_low()){
- zone_gc_forced = TRUE;
+__header_always_inline void
+zone_meta_remqueue(zone_t z, struct zone_page_metadata *meta)
+{
+ zone_pva_t meta_pva = zone_pva_from_meta(meta);
+ struct zone_page_metadata *tmp;
+
+ if (!zone_pva_is_null(meta->zm_page_next)) {
+ tmp = zone_pva_to_meta(meta->zm_page_next);
+ if (!zone_pva_is_equal(tmp->zm_page_prev, meta_pva)) {
+ zone_page_metadata_list_corruption(z, meta);
+ }
+ tmp->zm_page_prev = meta->zm_page_prev;
}
- unlock_zone(zone);
+ if (zone_pva_is_queue(meta->zm_page_prev)) {
+ zone_queue_set_head(z, meta->zm_page_prev, meta_pva, meta);
+ } else {
+ tmp = zone_pva_to_meta(meta->zm_page_prev);
+ if (!zone_pva_is_equal(tmp->zm_page_next, meta_pva)) {
+ zone_page_metadata_list_corruption(z, meta);
+ }
+ tmp->zm_page_next = meta->zm_page_next;
+ }
+
+ meta->zm_page_next = meta->zm_page_prev = (zone_pva_t){ 0 };
}
+__header_always_inline void
+zone_meta_requeue(zone_t z, zone_pva_t *headp,
+ struct zone_page_metadata *meta)
+{
+ zone_meta_remqueue(z, meta);
+ zone_meta_queue_push(z, headp, meta);
+}
-/* Change a zone's flags.
- * This routine must be called immediately after zinit.
- */
-void
-zone_change(
- zone_t zone,
- unsigned int item,
- boolean_t value)
+/* prevents a given metadata from ever reaching the z_pageq_empty queue */
+static inline void
+zone_meta_lock_in_partial(zone_t z, struct zone_page_metadata *m, uint32_t len)
{
- assert( zone != ZONE_NULL );
- assert( value == TRUE || value == FALSE );
+ uint16_t new_size = zone_meta_alloc_size_add(z, m, ZM_ALLOC_SIZE_LOCK);
- switch(item){
- case Z_EXHAUST:
- zone->exhaustible = value;
- break;
- case Z_COLLECT:
- zone->collectable = value;
- break;
- case Z_EXPAND:
- zone->expandable = value;
- break;
- case Z_FOREIGN:
- zone->allows_foreign = value;
- break;
-#if MACH_ASSERT
- default:
- panic("Zone_change: Wrong Item Type!");
- /* break; */
-#endif
+ assert(new_size % sizeof(vm_offset_t) == ZM_ALLOC_SIZE_LOCK);
+ if (new_size == ZM_ALLOC_SIZE_LOCK) {
+ zone_meta_requeue(z, &z->z_pageq_partial, m);
+ zone_counter_sub(z, z_wired_empty, len);
+ }
+}
+
+/* allows a given metadata to reach the z_pageq_empty queue again */
+static inline void
+zone_meta_unlock_from_partial(zone_t z, struct zone_page_metadata *m, uint32_t len)
+{
+ uint16_t new_size = zone_meta_alloc_size_sub(z, m, ZM_ALLOC_SIZE_LOCK);
+
+ assert(new_size % sizeof(vm_offset_t) == 0);
+ if (new_size == 0) {
+ zone_meta_requeue(z, &z->z_pageq_empty, m);
+ z->z_wired_empty += len;
}
- lock_zone_init(zone);
}
/*
- * Return the expected number of free elements in the zone.
- * This calculation will be incorrect if items are zfree'd that
- * were never zalloc'd/zget'd. The correct way to stuff memory
- * into a zone is by zcram.
+ * Routine to populate a page backing metadata in the zone_metadata_region.
+ * Must be called without the zone lock held as it might potentially block.
*/
-
-integer_t
-zone_free_count(zone_t zone)
+static void
+zone_meta_populate(vm_offset_t base, vm_size_t size)
{
- integer_t free_count;
+ struct zone_page_metadata *from = zone_meta_from_addr(base);
+ struct zone_page_metadata *to = from + atop(size);
+ vm_offset_t page_addr = trunc_page(from);
+
+ for (; page_addr < (vm_offset_t)to; page_addr += PAGE_SIZE) {
+#if !KASAN_ZALLOC
+ /*
+ * This can race with another thread doing a populate on the same metadata
+ * page, where we see an updated pmap but unmapped KASan shadow, causing a
+ * fault in the shadow when we first access the metadata page. Avoid this
+ * by always synchronizing on the zone_metadata_region lock with KASan.
+ */
+ if (pmap_find_phys(kernel_pmap, page_addr)) {
+ continue;
+ }
+#endif
+
+ for (;;) {
+ kern_return_t ret = KERN_SUCCESS;
- lock_zone(zone);
- free_count = zone->cur_size/zone->elem_size - zone->count;
- unlock_zone(zone);
+ /* All updates to the zone_metadata_region are done under the zone_metadata_region_lck */
+ lck_mtx_lock(&zone_metadata_region_lck);
+ if (0 == pmap_find_phys(kernel_pmap, page_addr)) {
+ ret = kernel_memory_populate(kernel_map, page_addr,
+ PAGE_SIZE, KMA_NOPAGEWAIT | KMA_KOBJECT | KMA_ZERO,
+ VM_KERN_MEMORY_OSFMK);
+ }
+ lck_mtx_unlock(&zone_metadata_region_lck);
- assert(free_count >= 0);
+ if (ret == KERN_SUCCESS) {
+ break;
+ }
- return(free_count);
+ /*
+ * We can't pass KMA_NOPAGEWAIT under a global lock as it leads
+ * to bad system deadlocks, so if the allocation failed,
+ * we need to do the VM_PAGE_WAIT() outside of the lock.
+ */
+ VM_PAGE_WAIT();
+ }
+ }
}
-/*
- * zprealloc preallocates wired memory, exanding the specified
- * zone to the specified size
- */
-void
-zprealloc(
- zone_t zone,
- vm_size_t size)
+__header_always_inline
+struct zone_page_metadata *
+zone_element_validate(zone_t zone, zone_element_t ze)
{
- vm_offset_t addr;
+ struct zone_page_metadata *meta;
+ vm_offset_t page = zone_element_base(ze);
- if (size != 0) {
- if (kmem_alloc_wired(zone_map, &addr, size) != KERN_SUCCESS)
- panic("zprealloc");
- zone_page_init(addr, size, ZONE_PAGE_USED);
- zcram(zone, (void *)addr, size);
+ if (!from_zone_map(page, 1, ZONE_ADDR_NATIVE) &&
+ !from_zone_map(page, 1, ZONE_ADDR_FOREIGN)) {
+ zone_invalid_element_panic(zone, ze);
}
-}
+ meta = zone_meta_from_addr(page);
-/*
- * Zone garbage collection subroutines
- */
+ if (meta->zm_chunk_len > ZM_CHUNK_LEN_MAX) {
+ zone_invalid_element_panic(zone, ze);
+ }
+ if (zone_element_idx(ze) >= zone->z_chunk_elems) {
+ zone_invalid_element_panic(zone, ze);
+ }
-boolean_t
-zone_page_collectable(
- vm_offset_t addr,
- vm_size_t size)
+ if (!zone_has_index(zone, meta->zm_index)) {
+ vm_offset_t addr = zone_element_addr(ze, zone_elem_size(zone));
+ zone_page_metadata_index_confusion_panic(zone, addr, meta);
+ }
+
+ return meta;
+}
+
+__attribute__((always_inline))
+static struct zone_page_metadata *
+zone_element_resolve(zone_t zone, vm_offset_t addr, vm_offset_t esize,
+ zone_element_t *ze)
{
- struct zone_page_table_entry *zp;
- natural_t i, j;
+ struct zone_page_metadata *meta;
+ vm_offset_t page, eidx;
-#if MACH_ASSERT
- if (!from_zone_map(addr, size))
- panic("zone_page_collectable");
-#endif
+ if (!from_zone_map(addr, esize, ZONE_ADDR_NATIVE) &&
+ !from_zone_map(addr, esize, ZONE_ADDR_FOREIGN)) {
+ zone_invalid_element_addr_panic(zone, addr);
+ }
+ page = trunc_page(addr);
+ meta = zone_meta_from_addr(addr);
+
+ if (meta->zm_chunk_len == ZM_SECONDARY_PCPU_PAGE) {
+ zone_invalid_element_addr_panic(zone, addr);
+ }
+ if (meta->zm_chunk_len == ZM_SECONDARY_PAGE) {
+ page -= ptoa(meta->zm_page_index);
+ meta -= meta->zm_page_index;
+ }
- i = atop_32(addr-zone_map_min_address);
- j = atop_32((addr+size-1) - zone_map_min_address);
+ eidx = (addr - page) / esize;
+ if ((addr - page) % esize) {
+ zone_invalid_element_addr_panic(zone, addr);
+ }
- for (zp = zone_page_table + i; i <= j; zp++, i++)
- if (zp->collect_count == zp->alloc_count)
- return (TRUE);
+ if (!zone_has_index(zone, meta->zm_index)) {
+ zone_page_metadata_index_confusion_panic(zone, addr, meta);
+ }
- return (FALSE);
+ *ze = zone_element_encode(page, eidx, ZPM_AUTO);
+ return meta;
}
-void
-zone_page_keep(
- vm_offset_t addr,
- vm_size_t size)
+/* Routine to get the size of a zone allocated address.
+ * If the address doesnt belong to the zone maps, returns 0.
+ */
+vm_size_t
+zone_element_size(void *addr, zone_t *z)
{
- struct zone_page_table_entry *zp;
- natural_t i, j;
+ struct zone *src_zone;
-#if MACH_ASSERT
- if (!from_zone_map(addr, size))
- panic("zone_page_keep");
-#endif
+ if (from_zone_map(addr, sizeof(void *), ZONE_ADDR_NATIVE) ||
+ from_zone_map(addr, sizeof(void *), ZONE_ADDR_FOREIGN)) {
+ src_zone = &zone_array[zone_index_from_ptr(addr)];
+ if (z) {
+ *z = src_zone;
+ }
+ return zone_elem_size(src_zone);
+ }
- i = atop_32(addr-zone_map_min_address);
- j = atop_32((addr+size-1) - zone_map_min_address);
+#if CONFIG_GZALLOC
+ if (__improbable(gzalloc_enabled())) {
+ vm_size_t gzsize;
+ if (gzalloc_element_size(addr, z, &gzsize)) {
+ return gzsize;
+ }
+ }
+#endif /* CONFIG_GZALLOC */
- for (zp = zone_page_table + i; i <= j; zp++, i++)
- zp->collect_count = 0;
+ return 0;
}
-void
-zone_page_collect(
- vm_offset_t addr,
- vm_size_t size)
+/* This function just formats the reason for the panics by redoing the checks */
+__abortlike
+static void
+zone_require_panic(zone_t zone, void *addr)
{
- struct zone_page_table_entry *zp;
- natural_t i, j;
+ uint32_t zindex;
+ zone_t other;
-#if MACH_ASSERT
- if (!from_zone_map(addr, size))
- panic("zone_page_collect");
-#endif
+ if (!from_zone_map(addr, zone_elem_size(zone), ZONE_ADDR_NATIVE)) {
+ panic("zone_require failed: address not in a zone (addr: %p)", addr);
+ }
- i = atop_32(addr-zone_map_min_address);
- j = atop_32((addr+size-1) - zone_map_min_address);
+ zindex = zone_index_from_ptr(addr);
+ other = &zone_array[zindex];
+ if (zindex >= os_atomic_load(&num_zones, relaxed) || !other->z_self) {
+ panic("zone_require failed: invalid zone index %d "
+ "(addr: %p, expected: %s%s)", zindex,
+ addr, zone_heap_name(zone), zone->z_name);
+ } else {
+ panic("zone_require failed: address in unexpected zone id %d (%s%s) "
+ "(addr: %p, expected: %s%s)",
+ zindex, zone_heap_name(other), other->z_name,
+ addr, zone_heap_name(zone), zone->z_name);
+ }
+}
- for (zp = zone_page_table + i; i <= j; zp++, i++)
- ++zp->collect_count;
+__abortlike
+static void
+zone_id_require_panic(zone_id_t zid, void *addr)
+{
+ zone_require_panic(&zone_array[zid], addr);
}
+/*
+ * Routines to panic if a pointer is not mapped to an expected zone.
+ * This can be used as a means of pinning an object to the zone it is expected
+ * to be a part of. Causes a panic if the address does not belong to any
+ * specified zone, does not belong to any zone, has been freed and therefore
+ * unmapped from the zone, or the pointer contains an uninitialized value that
+ * does not belong to any zone.
+ *
+ * Note that this can only work with collectable zones without foreign pages.
+ */
void
-zone_page_init(
- vm_offset_t addr,
- vm_size_t size,
- int value)
+zone_require(zone_t zone, void *addr)
{
- struct zone_page_table_entry *zp;
- natural_t i, j;
+ vm_size_t esize = zone_elem_size(zone);
-#if MACH_ASSERT
- if (!from_zone_map(addr, size))
- panic("zone_page_init");
+ if (__probable(from_zone_map(addr, esize, ZONE_ADDR_NATIVE))) {
+ if (zone_has_index(zone, zone_index_from_ptr(addr))) {
+ return;
+ }
+#if CONFIG_GZALLOC
+ } else if (__probable(zone->gzalloc_tracked)) {
+ return;
#endif
-
- i = atop_32(addr-zone_map_min_address);
- j = atop_32((addr+size-1) - zone_map_min_address);
-
- for (zp = zone_page_table + i; i <= j; zp++, i++) {
- zp->alloc_count = value;
- zp->collect_count = 0;
}
+ zone_require_panic(zone, addr);
}
void
-zone_page_alloc(
- vm_offset_t addr,
- vm_size_t size)
+zone_id_require(zone_id_t zid, vm_size_t esize, void *addr)
{
- struct zone_page_table_entry *zp;
- natural_t i, j;
-
-#if MACH_ASSERT
- if (!from_zone_map(addr, size))
- panic("zone_page_alloc");
+ if (__probable(from_zone_map(addr, esize, ZONE_ADDR_NATIVE))) {
+ if (zid == zone_index_from_ptr(addr)) {
+ return;
+ }
+#if CONFIG_GZALLOC
+ } else if (__probable(zone_array[zid].gzalloc_tracked)) {
+ return;
#endif
-
- i = atop_32(addr-zone_map_min_address);
- j = atop_32((addr+size-1) - zone_map_min_address);
-
- for (zp = zone_page_table + i; i <= j; zp++, i++) {
- /*
- * Set alloc_count to (ZONE_PAGE_USED + 1) if
- * it was previously set to ZONE_PAGE_UNUSED.
- */
- if (zp->alloc_count == ZONE_PAGE_UNUSED)
- zp->alloc_count = 1;
- else
- ++zp->alloc_count;
}
+ zone_id_require_panic(zid, addr);
}
void
-zone_page_free_element(
- struct zone_page_table_entry **free_pages,
- vm_offset_t addr,
- vm_size_t size)
+zone_id_require_allow_foreign(zone_id_t zid, vm_size_t esize, void *addr)
{
- struct zone_page_table_entry *zp;
- natural_t i, j;
-
-#if MACH_ASSERT
- if (!from_zone_map(addr, size))
- panic("zone_page_free_element");
+ if (__probable(from_zone_map(addr, esize, ZONE_ADDR_NATIVE) ||
+ from_zone_map(addr, esize, ZONE_ADDR_FOREIGN))) {
+ if (zid == zone_index_from_ptr(addr)) {
+ return;
+ }
+#if CONFIG_GZALLOC
+ } else if (__probable(zone_array[zid].gzalloc_tracked)) {
+ return;
#endif
+ }
+ zone_id_require_panic(zid, addr);
+}
- i = atop_32(addr-zone_map_min_address);
- j = atop_32((addr+size-1) - zone_map_min_address);
-
- for (zp = zone_page_table + i; i <= j; zp++, i++) {
- if (zp->collect_count > 0)
- --zp->collect_count;
- if (--zp->alloc_count == 0) {
- zp->alloc_count = ZONE_PAGE_UNUSED;
- zp->collect_count = 0;
+bool
+zone_owns(zone_t zone, void *addr)
+{
+ vm_size_t esize = zone_elem_size(zone);
- zp->link = *free_pages;
- *free_pages = zp;
- }
+ if (__probable(from_zone_map(addr, esize, ZONE_ADDR_NATIVE))) {
+ return zone_has_index(zone, zone_index_from_ptr(addr));
+#if CONFIG_GZALLOC
+ } else if (__probable(zone->gzalloc_tracked)) {
+ return true;
+#endif
}
+ return false;
}
+#endif /* !ZALLOC_TEST */
+#pragma mark Zone bits allocator
-/* This is used for walking through a zone's free element list.
+/*!
+ * @defgroup Zone Bitmap allocator
+ * @{
+ *
+ * @brief
+ * Functions implementing the zone bitmap allocator
+ *
+ * @discussion
+ * The zone allocator maintains which elements are allocated or free in bitmaps.
+ *
+ * When the number of elements per page is smaller than 32, it is stored inline
+ * on the @c zone_page_metadata structure (@c zm_inline_bitmap is set,
+ * and @c zm_bitmap used for storage).
+ *
+ * When the number of elements is larger, then a bitmap is allocated from
+ * a buddy allocator (impelemented under the @c zba_* namespace). Pointers
+ * to bitmaps are implemented as a packed 32 bit bitmap reference, stored in
+ * @c zm_bitmap. The low 3 bits encode the scale (order) of the allocation in
+ * @c ZBA_GRANULE units, and hence actual allocations encoded with that scheme
+ * cannot be larger than 1024 bytes (8192 bits).
+ *
+ * This buddy allocator can actually accomodate allocations as large
+ * as 8k on 16k systems and 2k on 4k systems.
+ *
+ * Note: @c zba_* functions are implementation details not meant to be used
+ * outside of the allocation of the allocator itself. Interfaces to the rest of
+ * the zone allocator are documented and not @c zba_* prefixed.
*/
-struct zone_free_element {
- struct zone_free_element * next;
+
+#define ZBA_CHUNK_SIZE PAGE_MAX_SIZE
+#define ZBA_GRANULE sizeof(uint64_t)
+#define ZBA_GRANULE_BITS (8 * sizeof(uint64_t))
+#define ZBA_MAX_ORDER (PAGE_MAX_SHIFT - 4)
+#define ZBA_MAX_ALLOC_ORDER 7
+#define ZBA_SLOTS (ZBA_CHUNK_SIZE / ZBA_GRANULE)
+static_assert(2ul * ZBA_GRANULE << ZBA_MAX_ORDER == ZBA_CHUNK_SIZE, "chunk sizes");
+static_assert(ZBA_MAX_ALLOC_ORDER <= ZBA_MAX_ORDER, "ZBA_MAX_ORDER is enough");
+
+struct zone_bits_chain {
+ uint32_t zbc_next;
+ uint32_t zbc_prev;
+} __attribute__((aligned(ZBA_GRANULE)));
+
+struct zone_bits_head {
+ uint32_t zbh_next;
+ uint32_t zbh_unused;
+} __attribute__((aligned(ZBA_GRANULE)));
+
+static_assert(sizeof(struct zone_bits_chain) == ZBA_GRANULE, "zbc size");
+static_assert(sizeof(struct zone_bits_head) == ZBA_GRANULE, "zbh size");
+
+struct zone_bits_allocator_meta {
+ uint32_t zbam_chunks;
+ uint32_t __zbam_padding;
+ struct zone_bits_head zbam_lists[ZBA_MAX_ORDER + 1];
};
-struct {
- uint32_t pgs_freed;
+struct zone_bits_allocator_header {
+ uint64_t zbah_bits[ZBA_SLOTS / (8 * sizeof(uint64_t))];
+};
- uint32_t elems_collected,
- elems_freed,
- elems_kept;
-} zgc_stats;
+#if ZALLOC_TEST
+static struct zalloc_bits_allocator_test_setup {
+ vm_offset_t zbats_base;
+ void (*zbats_populate)(vm_address_t addr, vm_size_t size);
+} zba_test_info;
-/* Zone garbage collection
- *
- * zone_gc will walk through all the free elements in all the
- * zones that are marked collectable looking for reclaimable
- * pages. zone_gc is called by consider_zone_gc when the system
- * begins to run out of memory.
- */
-void
-zone_gc(void)
+static struct zone_bits_allocator_header *
+zba_base_header(void)
{
- unsigned int max_zones;
- zone_t z;
- unsigned int i;
- struct zone_page_table_entry *zp, *zone_free_pages;
-
- mutex_lock(&zone_gc_lock);
-
- simple_lock(&all_zones_lock);
- max_zones = num_zones;
- z = first_zone;
- simple_unlock(&all_zones_lock);
-
-#if MACH_ASSERT
- for (i = 0; i < zone_pages; i++)
- assert(zone_page_table[i].collect_count == 0);
-#endif /* MACH_ASSERT */
+ return (struct zone_bits_allocator_header *)zba_test_info.zbats_base;
+}
- zone_free_pages = NULL;
+static void
+zba_populate(uint32_t n)
+{
+ vm_address_t base = zba_test_info.zbats_base;
+ zba_test_info.zbats_populate(base + n * ZBA_CHUNK_SIZE, ZBA_CHUNK_SIZE);
+}
+#else
+__startup_data
+static uint8_t zba_chunk_startup[ZBA_CHUNK_SIZE]
+__attribute__((aligned(ZBA_CHUNK_SIZE)));
+static LCK_MTX_EARLY_DECLARE(zba_mtx, &zone_locks_grp);
- for (i = 0; i < max_zones; i++, z = z->next_zone) {
- unsigned int n, m;
- vm_size_t elt_size, size_freed;
- struct zone_free_element *elt, *base_elt, *base_prev, *prev, *scan, *keep, *tail;
+static struct zone_bits_allocator_header *
+zba_base_header(void)
+{
+ return (struct zone_bits_allocator_header *)zone_info.zi_bits_range.min_address;
+}
- assert(z != ZONE_NULL);
+static void
+zba_lock(void)
+{
+ lck_mtx_lock(&zba_mtx);
+}
- if (!z->collectable)
- continue;
+static void
+zba_unlock(void)
+{
+ lck_mtx_unlock(&zba_mtx);
+}
- lock_zone(z);
+static void
+zba_populate(uint32_t n)
+{
+ vm_size_t size = ZBA_CHUNK_SIZE;
+ vm_address_t addr;
+
+ addr = zone_info.zi_bits_range.min_address + n * size;
+ if (addr >= zone_info.zi_bits_range.max_address) {
+ zone_t z = zone_find_largest();
+ panic("zba_populate: out of bitmap space, "
+ "likely due to memory leak in zone [%s%s] "
+ "(%luM, %d elements allocated)",
+ zone_heap_name(z), zone_name(z),
+ (unsigned long)zone_size_wired(z) >> 20,
+ zone_count_allocated(z));
+ }
- elt_size = z->elem_size;
+ for (;;) {
+ kern_return_t kr = KERN_SUCCESS;
- /*
- * Do a quick feasability check before we scan the zone:
- * skip unless there is likelihood of getting pages back
- * (i.e we need a whole allocation block's worth of free
- * elements before we can garbage collect) and
- * the zone has more than 10 percent of it's elements free
- */
- if (((z->cur_size - z->count * elt_size) <= (2 * z->alloc_size)) ||
- ((z->cur_size - z->count * elt_size) <= (z->cur_size / 10))) {
- unlock_zone(z);
- continue;
+ if (0 == pmap_find_phys(kernel_pmap, addr)) {
+ kr = kernel_memory_populate(kernel_map, addr, size,
+ KMA_NOPAGEWAIT | KMA_KOBJECT | KMA_ZERO,
+ VM_KERN_MEMORY_OSFMK);
}
- z->doing_gc = TRUE;
+ if (kr == KERN_SUCCESS) {
+ return;
+ }
- /*
- * Snatch all of the free elements away from the zone.
- */
+ zba_unlock();
+ VM_PAGE_WAIT();
+ zba_lock();
+ }
+}
+#endif
- scan = (void *)z->free_elements;
- z->free_elements = 0;
+__pure2
+static struct zone_bits_allocator_meta *
+zba_meta(void)
+{
+ return (struct zone_bits_allocator_meta *)&zba_base_header()[1];
+}
- unlock_zone(z);
+__pure2
+static uint64_t *
+zba_slot_base(void)
+{
+ return (uint64_t *)zba_base_header();
+}
- /*
- * Pass 1:
- *
- * Determine which elements we can attempt to collect
- * and count them up in the page table. Foreign elements
- * are returned to the zone.
- */
+__pure2
+static vm_address_t
+zba_page_addr(uint32_t n)
+{
+ return (vm_address_t)zba_base_header() + n * ZBA_CHUNK_SIZE;
+}
- prev = (void *)&scan;
- elt = scan;
- n = 0; tail = keep = NULL;
- while (elt != NULL) {
- if (from_zone_map(elt, elt_size)) {
- zone_page_collect((vm_offset_t)elt, elt_size);
+__pure2
+static struct zone_bits_head *
+zba_head(uint32_t order)
+{
+ return &zba_meta()->zbam_lists[order];
+}
- prev = elt;
- elt = elt->next;
+__pure2
+static uint32_t
+zba_head_index(uint32_t order)
+{
+ uint32_t hdr_size = sizeof(struct zone_bits_allocator_header) +
+ offsetof(struct zone_bits_allocator_meta, zbam_lists);
+ return (hdr_size / ZBA_GRANULE) + order;
+}
- ++zgc_stats.elems_collected;
- }
- else {
- if (keep == NULL)
- keep = tail = elt;
- else
- tail = tail->next = elt;
-
- elt = prev->next = elt->next;
- tail->next = NULL;
- }
+__pure2
+static struct zone_bits_chain *
+zba_chain_for_index(uint32_t index)
+{
+ return (struct zone_bits_chain *)(zba_slot_base() + index);
+}
- /*
- * Dribble back the elements we are keeping.
- */
+__pure2
+static uint32_t
+zba_chain_to_index(const struct zone_bits_chain *zbc)
+{
+ return (uint32_t)((const uint64_t *)zbc - zba_slot_base());
+}
- if (++n >= 50) {
- if (z->waiting == TRUE) {
- lock_zone(z);
-
- if (keep != NULL) {
- tail->next = (void *)z->free_elements;
- z->free_elements = (vm_offset_t) keep;
- tail = keep = NULL;
- } else {
- m =0;
- base_elt = elt;
- base_prev = prev;
- while ((elt != NULL) && (++m < 50)) {
- prev = elt;
- elt = elt->next;
- }
- if (m !=0 ) {
- prev->next = (void *)z->free_elements;
- z->free_elements = (vm_offset_t) base_elt;
- base_prev->next = elt;
- prev = base_prev;
- }
- }
-
- if (z->waiting) {
- z->waiting = FALSE;
- zone_wakeup(z);
- }
-
- unlock_zone(z);
- }
- n =0;
- }
- }
+__abortlike
+static void
+zba_head_corruption_panic(uint32_t order)
+{
+ panic("zone bits allocator head[%d:%p] is corrupt", order,
+ zba_head(order));
+}
- /*
- * Return any remaining elements.
- */
+__abortlike
+static void
+zba_chain_corruption_panic(struct zone_bits_chain *a, struct zone_bits_chain *b)
+{
+ panic("zone bits allocator freelist is corrupt (%p <-> %p)", a, b);
+}
- if (keep != NULL) {
- lock_zone(z);
+static void
+zba_push_block(struct zone_bits_chain *zbc, uint32_t order)
+{
+ struct zone_bits_head *hd = zba_head(order);
+ uint32_t hd_index = zba_head_index(order);
+ uint32_t index = zba_chain_to_index(zbc);
+ struct zone_bits_chain *next;
+
+ if (hd->zbh_next) {
+ next = zba_chain_for_index(hd->zbh_next);
+ if (next->zbc_prev != hd_index) {
+ zba_head_corruption_panic(order);
+ }
+ next->zbc_prev = index;
+ }
+ zbc->zbc_next = hd->zbh_next;
+ zbc->zbc_prev = hd_index;
+ hd->zbh_next = index;
+}
- tail->next = (void *)z->free_elements;
- z->free_elements = (vm_offset_t) keep;
+static void
+zba_remove_block(struct zone_bits_chain *zbc)
+{
+ struct zone_bits_chain *prev = zba_chain_for_index(zbc->zbc_prev);
+ uint32_t index = zba_chain_to_index(zbc);
- unlock_zone(z);
+ if (prev->zbc_next != index) {
+ zba_chain_corruption_panic(prev, zbc);
+ }
+ if ((prev->zbc_next = zbc->zbc_next)) {
+ struct zone_bits_chain *next = zba_chain_for_index(zbc->zbc_next);
+ if (next->zbc_prev != index) {
+ zba_chain_corruption_panic(zbc, next);
}
+ next->zbc_prev = zbc->zbc_prev;
+ }
+}
- /*
- * Pass 2:
- *
- * Determine which pages we can reclaim and
- * free those elements.
- */
+static vm_address_t
+zba_try_pop_block(uint32_t order)
+{
+ struct zone_bits_head *hd = zba_head(order);
+ struct zone_bits_chain *zbc;
- size_freed = 0;
- prev = (void *)&scan;
- elt = scan;
- n = 0; tail = keep = NULL;
- while (elt != NULL) {
- if (zone_page_collectable((vm_offset_t)elt, elt_size)) {
- size_freed += elt_size;
- zone_page_free_element(&zone_free_pages,
- (vm_offset_t)elt, elt_size);
+ if (hd->zbh_next == 0) {
+ return 0;
+ }
- elt = prev->next = elt->next;
+ zbc = zba_chain_for_index(hd->zbh_next);
+ zba_remove_block(zbc);
+ return (vm_address_t)zbc;
+}
- ++zgc_stats.elems_freed;
- }
- else {
- zone_page_keep((vm_offset_t)elt, elt_size);
+static struct zone_bits_allocator_header *
+zba_header(vm_offset_t addr)
+{
+ addr &= -(vm_offset_t)ZBA_CHUNK_SIZE;
+ return (struct zone_bits_allocator_header *)addr;
+}
- if (keep == NULL)
- keep = tail = elt;
- else
- tail = tail->next = elt;
+static size_t
+zba_node_parent(size_t node)
+{
+ return (node - 1) / 2;
+}
- elt = prev->next = elt->next;
- tail->next = NULL;
+static size_t
+zba_node_left_child(size_t node)
+{
+ return node * 2 + 1;
+}
- ++zgc_stats.elems_kept;
- }
+static size_t
+zba_node_buddy(size_t node)
+{
+ return ((node - 1) ^ 1) + 1;
+}
- /*
- * Dribble back the elements we are keeping,
- * and update the zone size info.
- */
+static size_t
+zba_node(vm_offset_t addr, uint32_t order)
+{
+ vm_offset_t offs = (addr % ZBA_CHUNK_SIZE) / ZBA_GRANULE;
+ return (offs >> order) + (1 << (ZBA_MAX_ORDER - order + 1)) - 1;
+}
- if (++n >= 50) {
- lock_zone(z);
+static struct zone_bits_chain *
+zba_chain_for_node(struct zone_bits_allocator_header *zbah, size_t node, uint32_t order)
+{
+ vm_offset_t offs = (node - (1 << (ZBA_MAX_ORDER - order + 1)) + 1) << order;
+ return (struct zone_bits_chain *)((vm_offset_t)zbah + offs * ZBA_GRANULE);
+}
- z->cur_size -= size_freed;
- size_freed = 0;
+static void
+zba_node_flip_split(struct zone_bits_allocator_header *zbah, size_t node)
+{
+ zbah->zbah_bits[node / 64] ^= 1ull << (node % 64);
+}
- if (keep != NULL) {
- tail->next = (void *)z->free_elements;
- z->free_elements = (vm_offset_t) keep;
- }
+static bool
+zba_node_is_split(struct zone_bits_allocator_header *zbah, size_t node)
+{
+ return zbah->zbah_bits[node / 64] & (1ull << (node % 64));
+}
- if (z->waiting) {
- z->waiting = FALSE;
- zone_wakeup(z);
- }
+static void
+zba_free(vm_offset_t addr, uint32_t order)
+{
+ struct zone_bits_allocator_header *zbah = zba_header(addr);
+ struct zone_bits_chain *zbc;
+ size_t node = zba_node(addr, order);
- unlock_zone(z);
+ while (node) {
+ size_t parent = zba_node_parent(node);
- n = 0; tail = keep = NULL;
- }
+ zba_node_flip_split(zbah, parent);
+ if (zba_node_is_split(zbah, parent)) {
+ break;
}
- /*
- * Return any remaining elements, and update
- * the zone size info.
- */
+ zbc = zba_chain_for_node(zbah, zba_node_buddy(node), order);
+ zba_remove_block(zbc);
+ order++;
+ node = parent;
+ }
- lock_zone(z);
+ zba_push_block(zba_chain_for_node(zbah, node, order), order);
+}
+
+static vm_size_t
+zba_chunk_header_size(uint32_t n)
+{
+ vm_size_t hdr_size = sizeof(struct zone_bits_allocator_header);
+ if (n == 0) {
+ hdr_size += sizeof(struct zone_bits_allocator_meta);
+ }
+ return hdr_size;
+}
- if (size_freed > 0 || keep != NULL) {
+static void
+zba_init_chunk(uint32_t n)
+{
+ vm_size_t hdr_size = zba_chunk_header_size(n);
+ vm_offset_t page = zba_page_addr(n);
+ struct zone_bits_allocator_header *zbah = zba_header(page);
+ vm_size_t size = ZBA_CHUNK_SIZE;
+ size_t node;
+
+ for (uint32_t o = ZBA_MAX_ORDER + 1; o-- > 0;) {
+ if (size < hdr_size + (ZBA_GRANULE << o)) {
+ continue;
+ }
+ size -= ZBA_GRANULE << o;
+ node = zba_node(page + size, o);
+ zba_node_flip_split(zbah, zba_node_parent(node));
+ zba_push_block(zba_chain_for_node(zbah, node, o), o);
+ }
- z->cur_size -= size_freed;
+ zba_meta()->zbam_chunks = n + 1;
+}
- if (keep != NULL) {
- tail->next = (void *)z->free_elements;
- z->free_elements = (vm_offset_t) keep;
- }
+__attribute__((noinline))
+static void
+zba_grow(void)
+{
+ uint32_t chunk = zba_meta()->zbam_chunks;
- }
+ zba_populate(chunk);
+ if (zba_meta()->zbam_chunks == chunk) {
+ zba_init_chunk(chunk);
+ }
+}
- z->doing_gc = FALSE;
- if (z->waiting) {
- z->waiting = FALSE;
- zone_wakeup(z);
+static vm_offset_t
+zba_alloc(uint32_t order)
+{
+ struct zone_bits_allocator_header *zbah;
+ uint32_t cur = order;
+ vm_address_t addr;
+ size_t node;
+
+ while ((addr = zba_try_pop_block(cur)) == 0) {
+ if (cur++ >= ZBA_MAX_ORDER) {
+ zba_grow();
+ cur = order;
}
- unlock_zone(z);
}
- /*
- * Reclaim the pages we are freeing.
- */
-
- while ((zp = zone_free_pages) != NULL) {
- zone_free_pages = zp->link;
- kmem_free(zone_map, zone_map_min_address + PAGE_SIZE *
- (zp - zone_page_table), PAGE_SIZE);
- ++zgc_stats.pgs_freed;
+ zbah = zba_header(addr);
+ node = zba_node(addr, cur);
+ zba_node_flip_split(zbah, zba_node_parent(node));
+ while (cur > order) {
+ cur--;
+ zba_node_flip_split(zbah, node);
+ node = zba_node_left_child(node);
+ zba_push_block(zba_chain_for_node(zbah, node + 1, cur), cur);
}
- mutex_unlock(&zone_gc_lock);
+ return addr;
}
-/*
- * consider_zone_gc:
- *
- * Called by the pageout daemon when the system needs more free pages.
- */
+#define zba_map_index(type, n) (n / (8 * sizeof(type)))
+#define zba_map_bit(type, n) ((type)1 << (n % (8 * sizeof(type))))
+#define zba_map_mask_lt(type, n) (zba_map_bit(type, n) - 1)
+#define zba_map_mask_ge(type, n) ((type)-zba_map_bit(type, n))
-void
-consider_zone_gc(void)
+#if !ZALLOC_TEST
+static uint32_t
+zba_bits_ref_order(uint32_t bref)
{
- /*
- * By default, don't attempt zone GC more frequently
- * than once / 1 minutes.
- */
-
- if (zone_gc_max_rate == 0)
- zone_gc_max_rate = (60 << SCHED_TICK_SHIFT) + 1;
-
- if (zone_gc_allowed &&
- ((sched_tick > (zone_gc_last_tick + zone_gc_max_rate)) ||
- zone_gc_forced)) {
- zone_gc_forced = FALSE;
- zone_gc_last_tick = sched_tick;
- zone_gc();
- }
+ return bref & 0x7;
}
+static bitmap_t *
+zba_bits_ref_ptr(uint32_t bref)
+{
+ return zba_slot_base() + (bref >> 3);
+}
-kern_return_t
-host_zone_info(
- host_t host,
- zone_name_array_t *namesp,
- mach_msg_type_number_t *namesCntp,
- zone_info_array_t *infop,
- mach_msg_type_number_t *infoCntp)
+static vm_offset_t
+zba_scan_bitmap_inline(zone_t zone, struct zone_page_metadata *meta,
+ vm_offset_t eidx)
{
- zone_name_t *names;
- vm_offset_t names_addr;
- vm_size_t names_size;
- zone_info_t *info;
- vm_offset_t info_addr;
- vm_size_t info_size;
- unsigned int max_zones, i;
- zone_t z;
- zone_name_t *zn;
- zone_info_t *zi;
- kern_return_t kr;
-
- if (host == HOST_NULL)
- return KERN_INVALID_HOST;
+ size_t i = eidx / 32;
+ uint32_t map;
+
+ if (eidx % 32) {
+ map = meta[i].zm_bitmap & zba_map_mask_ge(uint32_t, eidx);
+ if (map) {
+ eidx = __builtin_ctz(map);
+ meta[i].zm_bitmap ^= 1u << eidx;
+ return i * 32 + eidx;
+ }
+ i++;
+ }
+
+ uint32_t chunk_len = meta->zm_chunk_len;
+ if (chunk_len == 1 && zone->z_percpu) {
+ chunk_len = zpercpu_count();
+ }
+ for (int j = 0; j < chunk_len; j++, i++) {
+ if (i >= chunk_len) {
+ i = 0;
+ }
+ if (__probable(map = meta[i].zm_bitmap)) {
+ meta[i].zm_bitmap &= map - 1;
+ return i * 32 + __builtin_ctz(map);
+ }
+ }
+
+ zone_page_meta_accounting_panic(zone, meta, "zm_bitmap");
+}
+
+static vm_offset_t
+zba_scan_bitmap_ref(zone_t zone, struct zone_page_metadata *meta,
+ vm_offset_t eidx)
+{
+ uint32_t bits_size = 1 << zba_bits_ref_order(meta->zm_bitmap);
+ bitmap_t *bits = zba_bits_ref_ptr(meta->zm_bitmap);
+ size_t i = eidx / 64;
+ uint64_t map;
+
+ if (eidx % 64) {
+ map = bits[i] & zba_map_mask_ge(uint64_t, eidx);
+ if (map) {
+ eidx = __builtin_ctzll(map);
+ bits[i] ^= 1ull << eidx;
+ return i * 64 + eidx;
+ }
+ i++;
+ }
+
+ for (int j = 0; j < bits_size; i++, j++) {
+ if (i >= bits_size) {
+ i = 0;
+ }
+ if (__probable(map = bits[i])) {
+ bits[i] &= map - 1;
+ return i * 64 + __builtin_ctzll(map);
+ }
+ }
+
+ zone_page_meta_accounting_panic(zone, meta, "zm_bitmap");
+}
+
+/*!
+ * @function zone_meta_find_and_clear_bit
+ *
+ * @brief
+ * The core of the bitmap allocator: find a bit set in the bitmaps.
+ *
+ * @discussion
+ * This method will round robin through available allocations,
+ * with a per-core memory of the last allocated element index allocated.
+ *
+ * This is done in order to avoid a fully LIFO behavior which makes exploiting
+ * double-free bugs way too practical.
+ *
+ * @param zone The zone we're allocating from.
+ * @param meta The main metadata for the chunk being allocated from.
+ */
+static vm_offset_t
+zone_meta_find_and_clear_bit(zone_t zone, struct zone_page_metadata *meta)
+{
+ zone_stats_t zs = zpercpu_get(zone->z_stats);
+ vm_offset_t eidx = zs->zs_alloc_rr + 1;
+
+ if (meta->zm_inline_bitmap) {
+ eidx = zba_scan_bitmap_inline(zone, meta, eidx);
+ } else {
+ eidx = zba_scan_bitmap_ref(zone, meta, eidx);
+ }
+ zs->zs_alloc_rr = (uint16_t)eidx;
+ return eidx;
+}
+
+/*!
+ * @function zone_meta_bits_init
+ *
+ * @brief
+ * Initializes the zm_bitmap field(s) for a newly assigned chunk.
+ *
+ * @param meta The main metadata for the initialized chunk.
+ * @param count The number of elements the chunk can hold
+ * (which might be partial for partially populated chunks).
+ * @param nbits The maximum nuber of bits that will be used.
+ */
+static void
+zone_meta_bits_init(struct zone_page_metadata *meta,
+ uint32_t count, uint32_t nbits)
+{
+ static_assert(ZONE_MAX_ALLOC_SIZE / ZONE_MIN_ELEM_SIZE <=
+ ZBA_GRANULE_BITS << ZBA_MAX_ORDER, "bitmaps will be large enough");
+
+ if (meta->zm_inline_bitmap) {
+ /*
+ * We're called with the metadata zm_bitmap fields already
+ * zeroed out.
+ */
+ for (size_t i = 0; 32 * i < count; i++) {
+ if (32 * i + 32 <= count) {
+ meta[i].zm_bitmap = ~0u;
+ } else {
+ meta[i].zm_bitmap = zba_map_mask_lt(uint32_t, count);
+ }
+ }
+ } else {
+ uint32_t order = flsll((nbits - 1) / ZBA_GRANULE_BITS);
+ uint64_t *bits;
+
+ assert(order <= ZBA_MAX_ALLOC_ORDER);
+ assert(count <= ZBA_GRANULE_BITS << order);
+
+ zba_lock();
+ bits = (uint64_t *)zba_alloc(order);
+ zba_unlock();
+
+ for (size_t i = 0; i < 1u << order; i++) {
+ if (64 * i + 64 <= count) {
+ bits[i] = ~0ull;
+ } else if (64 * i < count) {
+ bits[i] = zba_map_mask_lt(uint64_t, count);
+ } else {
+ bits[i] = 0ull;
+ }
+ }
+
+ meta->zm_bitmap = (uint32_t)((vm_offset_t)bits -
+ (vm_offset_t)zba_slot_base()) + order;
+ }
+}
+
+/*!
+ * @function zone_meta_bits_merge
+ *
+ * @brief
+ * Adds elements <code>[start, end)</code> to a chunk being extended.
+ *
+ * @param meta The main metadata for the extended chunk.
+ * @param start The index of the first element to add to the chunk.
+ * @param end The index of the last (exclusive) element to add.
+ */
+static void
+zone_meta_bits_merge(struct zone_page_metadata *meta,
+ uint32_t start, uint32_t end)
+{
+ if (meta->zm_inline_bitmap) {
+ while (start < end) {
+ size_t s_i = start / 32;
+ size_t s_e = end / 32;
+
+ if (s_i == s_e) {
+ meta[s_i].zm_bitmap |= zba_map_mask_lt(uint32_t, end) &
+ zba_map_mask_ge(uint32_t, start);
+ break;
+ }
+
+ meta[s_i].zm_bitmap |= zba_map_mask_ge(uint32_t, start);
+ start += 32 - (start % 32);
+ }
+ } else {
+ uint64_t *bits = zba_bits_ref_ptr(meta->zm_bitmap);
+
+ while (start < end) {
+ size_t s_i = start / 64;
+ size_t s_e = end / 64;
+
+ if (s_i == s_e) {
+ bits[s_i] |= zba_map_mask_lt(uint64_t, end) &
+ zba_map_mask_ge(uint64_t, start);
+ break;
+ }
+ bits[s_i] |= zba_map_mask_ge(uint64_t, start);
+ start += 64 - (start % 64);
+ }
+ }
+}
+
+/*!
+ * @function zone_bits_free
+ *
+ * @brief
+ * Frees a bitmap to the zone bitmap allocator.
+ *
+ * @param bref
+ * A bitmap reference set by @c zone_meta_bits_init() in a @c zm_bitmap field.
+ */
+static void
+zone_bits_free(uint32_t bref)
+{
+ zba_lock();
+ zba_free((vm_offset_t)zba_bits_ref_ptr(bref), zba_bits_ref_order(bref));
+ zba_unlock();
+}
+
+/*!
+ * @function zone_meta_is_free
+ *
+ * @brief
+ * Returns whether a given element appears free.
+ */
+static bool
+zone_meta_is_free(struct zone_page_metadata *meta, zone_element_t ze)
+{
+ vm_offset_t eidx = zone_element_idx(ze);
+ if (meta->zm_inline_bitmap) {
+ uint32_t bit = zba_map_bit(uint32_t, eidx);
+ return meta[zba_map_index(uint32_t, eidx)].zm_bitmap & bit;
+ } else {
+ bitmap_t *bits = zba_bits_ref_ptr(meta->zm_bitmap);
+ uint64_t bit = zba_map_bit(uint64_t, eidx);
+ return bits[zba_map_index(uint64_t, eidx)] & bit;
+ }
+}
+
+/*!
+ * @function zone_meta_mark_free
+ *
+ * @brief
+ * Marks an element as free and returns whether it was marked as used.
+ */
+static bool
+zone_meta_mark_free(struct zone_page_metadata *meta, zone_element_t ze)
+{
+ vm_offset_t eidx = zone_element_idx(ze);
+
+ if (meta->zm_inline_bitmap) {
+ uint32_t bit = zba_map_bit(uint32_t, eidx);
+ if (meta[zba_map_index(uint32_t, eidx)].zm_bitmap & bit) {
+ return false;
+ }
+ meta[zba_map_index(uint32_t, eidx)].zm_bitmap ^= bit;
+ } else {
+ bitmap_t *bits = zba_bits_ref_ptr(meta->zm_bitmap);
+ uint64_t bit = zba_map_bit(uint64_t, eidx);
+ if (bits[zba_map_index(uint64_t, eidx)] & bit) {
+ return false;
+ }
+ bits[zba_map_index(uint64_t, eidx)] ^= bit;
+ }
+ return true;
+}
+
+/*!
+ * @function zone_meta_mark_used
+ *
+ * @brief
+ * Marks an element as used and returns whether it was marked as free
+ */
+static bool
+zone_meta_mark_used(struct zone_page_metadata *meta, zone_element_t ze)
+{
+ vm_offset_t eidx = zone_element_idx(ze);
+
+ if (meta->zm_inline_bitmap) {
+ uint32_t bit = zba_map_bit(uint32_t, eidx);
+ if (meta[zba_map_index(uint32_t, eidx)].zm_bitmap & bit) {
+ meta[zba_map_index(uint32_t, eidx)].zm_bitmap ^= bit;
+ return true;
+ }
+ } else {
+ bitmap_t *bits = zba_bits_ref_ptr(meta->zm_bitmap);
+ uint64_t bit = zba_map_bit(uint64_t, eidx);
+ if (bits[zba_map_index(uint64_t, eidx)] & bit) {
+ bits[zba_map_index(uint64_t, eidx)] ^= bit;
+ return true;
+ }
+ }
+ return false;
+}
+
+#endif /* !ZALLOC_TEST */
+/*! @} */
+#pragma mark ZTAGS
+#if !ZALLOC_TEST
+#if VM_MAX_TAG_ZONES
+/*
+ * Zone tagging allows for per "tag" accounting of allocations for the kalloc
+ * zones only.
+ *
+ * There are 3 kinds of tags that can be used:
+ * - pre-registered VM_KERN_MEMORY_*
+ * - dynamic tags allocated per call sites in core-kernel (using vm_tag_alloc())
+ * - per-kext tags computed by IOKit (using the magic VM_TAG_BT marker).
+ *
+ * The VM tracks the statistics in lazily allocated structures.
+ * See vm_tag_will_update_zone(), vm_tag_update_zone_size().
+ *
+ * If for some reason the requested tag cannot be accounted for,
+ * the tag is forced to VM_KERN_MEMORY_KALLOC which is pre-allocated.
+ *
+ * Each allocated element also remembers the tag it was assigned,
+ * in its ztSlot() which lets zalloc/zfree update statistics correctly.
+ */
+
+// for zones with tagging enabled:
+
+// calculate a pointer to the tag base entry,
+// holding either a uint32_t the first tag offset for a page in the zone map,
+// or two uint16_t tags if the page can only hold one or two elements
+
+#define ZTAGBASE(zone, element) \
+ (&((uint32_t *)zone_tagbase_min)[atop((element) - \
+ zone_info.zi_map_range[ZONE_ADDR_NATIVE].min_address)])
+
+static vm_offset_t zone_tagbase_min;
+static vm_offset_t zone_tagbase_max;
+static vm_offset_t zone_tagbase_map_size;
+static vm_map_t zone_tagbase_map;
+
+static vm_offset_t zone_tags_min;
+static vm_offset_t zone_tags_max;
+static vm_offset_t zone_tags_map_size;
+static vm_map_t zone_tags_map;
+
+// simple heap allocator for allocating the tags for new memory
+
+static LCK_MTX_EARLY_DECLARE(ztLock, &zone_locks_grp); /* heap lock */
+
+enum{
+ ztFreeIndexCount = 8,
+ ztFreeIndexMax = (ztFreeIndexCount - 1),
+ ztTagsPerBlock = 4
+};
+
+struct ztBlock {
+#if __LITTLE_ENDIAN__
+ uint64_t free:1,
+ next:21,
+ prev:21,
+ size:21;
+#else
+// ztBlock needs free bit least significant
+#error !__LITTLE_ENDIAN__
+#endif
+};
+typedef struct ztBlock ztBlock;
+
+static ztBlock * ztBlocks;
+static uint32_t ztBlocksCount;
+static uint32_t ztBlocksFree;
+
+static uint32_t
+ztLog2up(uint32_t size)
+{
+ if (1 == size) {
+ size = 0;
+ } else {
+ size = 32 - __builtin_clz(size - 1);
+ }
+ return size;
+}
+
+// pointer to the tag for an element
+static vm_tag_t *
+ztSlot(zone_t zone, vm_offset_t element)
+{
+ vm_tag_t *result;
+ if (zone->tags_inline) {
+ result = (vm_tag_t *)ZTAGBASE(zone, element);
+ if ((PAGE_MASK & element) >= zone_elem_size(zone)) {
+ result++;
+ }
+ } else {
+ result = &((vm_tag_t *)zone_tags_min)[ZTAGBASE(zone, element)[0] +
+ (element & PAGE_MASK) / zone_elem_size(zone)];
+ }
+ return result;
+}
+
+static uint32_t
+ztLog2down(uint32_t size)
+{
+ size = 31 - __builtin_clz(size);
+ return size;
+}
+
+static void
+ztFault(vm_map_t map, const void * address, size_t size, uint32_t flags)
+{
+ vm_map_offset_t addr = (vm_map_offset_t) address;
+ vm_map_offset_t page, end;
+
+ page = trunc_page(addr);
+ end = round_page(addr + size);
+
+ for (; page < end; page += page_size) {
+ if (!pmap_find_phys(kernel_pmap, page)) {
+ kern_return_t __unused
+ ret = kernel_memory_populate(map, page, PAGE_SIZE,
+ KMA_KOBJECT | flags, VM_KERN_MEMORY_DIAG);
+ assert(ret == KERN_SUCCESS);
+ }
+ }
+}
+
+static boolean_t
+ztPresent(const void * address, size_t size)
+{
+ vm_map_offset_t addr = (vm_map_offset_t) address;
+ vm_map_offset_t page, end;
+ boolean_t result;
+
+ page = trunc_page(addr);
+ end = round_page(addr + size);
+ for (result = TRUE; (page < end); page += page_size) {
+ result = pmap_find_phys(kernel_pmap, page);
+ if (!result) {
+ break;
+ }
+ }
+ return result;
+}
+
+
+void __unused
+ztDump(boolean_t sanity);
+void __unused
+ztDump(boolean_t sanity)
+{
+ uint32_t q, cq, p;
+
+ for (q = 0; q <= ztFreeIndexMax; q++) {
+ p = q;
+ do{
+ if (sanity) {
+ cq = ztLog2down(ztBlocks[p].size);
+ if (cq > ztFreeIndexMax) {
+ cq = ztFreeIndexMax;
+ }
+ if (!ztBlocks[p].free
+ || ((p != q) && (q != cq))
+ || (ztBlocks[ztBlocks[p].next].prev != p)
+ || (ztBlocks[ztBlocks[p].prev].next != p)) {
+ kprintf("zterror at %d", p);
+ ztDump(FALSE);
+ kprintf("zterror at %d", p);
+ assert(FALSE);
+ }
+ continue;
+ }
+ kprintf("zt[%03d]%c %d, %d, %d\n",
+ p, ztBlocks[p].free ? 'F' : 'A',
+ ztBlocks[p].next, ztBlocks[p].prev,
+ ztBlocks[p].size);
+ p = ztBlocks[p].next;
+ if (p == q) {
+ break;
+ }
+ }while (p != q);
+ if (!sanity) {
+ printf("\n");
+ }
+ }
+ if (!sanity) {
+ printf("-----------------------\n");
+ }
+}
+
+
+
+#define ZTBDEQ(idx) \
+ ztBlocks[ztBlocks[(idx)].prev].next = ztBlocks[(idx)].next; \
+ ztBlocks[ztBlocks[(idx)].next].prev = ztBlocks[(idx)].prev;
+
+static void
+ztFree(zone_t zone __unused, uint32_t index, uint32_t count)
+{
+ uint32_t q, w, p, size, merge;
+
+ assert(count);
+ ztBlocksFree += count;
+
+ // merge with preceding
+ merge = (index + count);
+ if ((merge < ztBlocksCount)
+ && ztPresent(&ztBlocks[merge], sizeof(ztBlocks[merge]))
+ && ztBlocks[merge].free) {
+ ZTBDEQ(merge);
+ count += ztBlocks[merge].size;
+ }
+
+ // merge with following
+ merge = (index - 1);
+ if ((merge > ztFreeIndexMax)
+ && ztPresent(&ztBlocks[merge], sizeof(ztBlocks[merge]))
+ && ztBlocks[merge].free) {
+ size = ztBlocks[merge].size;
+ count += size;
+ index -= size;
+ ZTBDEQ(index);
+ }
+
+ q = ztLog2down(count);
+ if (q > ztFreeIndexMax) {
+ q = ztFreeIndexMax;
+ }
+ w = q;
+ // queue in order of size
+ while (TRUE) {
+ p = ztBlocks[w].next;
+ if (p == q) {
+ break;
+ }
+ if (ztBlocks[p].size >= count) {
+ break;
+ }
+ w = p;
+ }
+ ztBlocks[p].prev = index;
+ ztBlocks[w].next = index;
+
+ // fault in first
+ ztFault(zone_tags_map, &ztBlocks[index], sizeof(ztBlocks[index]), 0);
+
+ // mark first & last with free flag and size
+ ztBlocks[index].free = TRUE;
+ ztBlocks[index].size = count;
+ ztBlocks[index].prev = w;
+ ztBlocks[index].next = p;
+ if (count > 1) {
+ index += (count - 1);
+ // fault in last
+ ztFault(zone_tags_map, &ztBlocks[index], sizeof(ztBlocks[index]), 0);
+ ztBlocks[index].free = TRUE;
+ ztBlocks[index].size = count;
+ }
+}
+
+static uint32_t
+ztAlloc(zone_t zone, uint32_t count)
+{
+ uint32_t q, w, p, leftover;
+
+ assert(count);
+
+ q = ztLog2up(count);
+ if (q > ztFreeIndexMax) {
+ q = ztFreeIndexMax;
+ }
+ do{
+ w = q;
+ while (TRUE) {
+ p = ztBlocks[w].next;
+ if (p == q) {
+ break;
+ }
+ if (ztBlocks[p].size >= count) {
+ // dequeue, mark both ends allocated
+ ztBlocks[w].next = ztBlocks[p].next;
+ ztBlocks[ztBlocks[p].next].prev = w;
+ ztBlocks[p].free = FALSE;
+ ztBlocksFree -= ztBlocks[p].size;
+ if (ztBlocks[p].size > 1) {
+ ztBlocks[p + ztBlocks[p].size - 1].free = FALSE;
+ }
+
+ // fault all the allocation
+ ztFault(zone_tags_map, &ztBlocks[p], count * sizeof(ztBlocks[p]), 0);
+ // mark last as allocated
+ if (count > 1) {
+ ztBlocks[p + count - 1].free = FALSE;
+ }
+ // free remainder
+ leftover = ztBlocks[p].size - count;
+ if (leftover) {
+ ztFree(zone, p + ztBlocks[p].size - leftover, leftover);
+ }
+
+ return p;
+ }
+ w = p;
+ }
+ q++;
+ }while (q <= ztFreeIndexMax);
+
+ return -1U;
+}
+
+__startup_func
+static void
+zone_tagging_init(vm_size_t max_zonemap_size)
+{
+ kern_return_t ret;
+ vm_map_kernel_flags_t vmk_flags;
+ uint32_t idx;
+
+ // allocate submaps VM_KERN_MEMORY_DIAG
+
+ zone_tagbase_map_size = atop(max_zonemap_size) * sizeof(uint32_t);
+ vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
+ vmk_flags.vmkf_permanent = TRUE;
+ ret = kmem_suballoc(kernel_map, &zone_tagbase_min, zone_tagbase_map_size,
+ FALSE, VM_FLAGS_ANYWHERE, vmk_flags, VM_KERN_MEMORY_DIAG,
+ &zone_tagbase_map);
+
+ if (ret != KERN_SUCCESS) {
+ panic("zone_init: kmem_suballoc failed");
+ }
+ zone_tagbase_max = zone_tagbase_min + round_page(zone_tagbase_map_size);
+
+ zone_tags_map_size = 2048 * 1024 * sizeof(vm_tag_t);
+ vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
+ vmk_flags.vmkf_permanent = TRUE;
+ ret = kmem_suballoc(kernel_map, &zone_tags_min, zone_tags_map_size,
+ FALSE, VM_FLAGS_ANYWHERE, vmk_flags, VM_KERN_MEMORY_DIAG,
+ &zone_tags_map);
+
+ if (ret != KERN_SUCCESS) {
+ panic("zone_init: kmem_suballoc failed");
+ }
+ zone_tags_max = zone_tags_min + round_page(zone_tags_map_size);
+
+ ztBlocks = (ztBlock *) zone_tags_min;
+ ztBlocksCount = (uint32_t)(zone_tags_map_size / sizeof(ztBlock));
+
+ // initialize the qheads
+ lck_mtx_lock(&ztLock);
+
+ ztFault(zone_tags_map, &ztBlocks[0], sizeof(ztBlocks[0]), 0);
+ for (idx = 0; idx < ztFreeIndexCount; idx++) {
+ ztBlocks[idx].free = TRUE;
+ ztBlocks[idx].next = idx;
+ ztBlocks[idx].prev = idx;
+ ztBlocks[idx].size = 0;
+ }
+ // free remaining space
+ ztFree(NULL, ztFreeIndexCount, ztBlocksCount - ztFreeIndexCount);
+
+ lck_mtx_unlock(&ztLock);
+}
+
+static void
+ztMemoryAdd(zone_t zone, vm_offset_t mem, vm_size_t size)
+{
+ uint32_t * tagbase;
+ uint32_t count, block, blocks, idx;
+ size_t pages;
+
+ pages = atop(size);
+ tagbase = ZTAGBASE(zone, mem);
+
+ lck_mtx_lock(&ztLock);
+
+ // fault tagbase
+ ztFault(zone_tagbase_map, tagbase, pages * sizeof(uint32_t), 0);
+
+ if (!zone->tags_inline) {
+ // allocate tags
+ count = (uint32_t)(size / zone_elem_size(zone));
+ blocks = ((count + ztTagsPerBlock - 1) / ztTagsPerBlock);
+ block = ztAlloc(zone, blocks);
+ if (-1U == block) {
+ ztDump(false);
+ }
+ assert(-1U != block);
+ }
+
+ lck_mtx_unlock(&ztLock);
+
+ if (!zone->tags_inline) {
+ // set tag base for each page
+ block *= ztTagsPerBlock;
+ for (idx = 0; idx < pages; idx++) {
+ vm_offset_t esize = zone_elem_size(zone);
+ tagbase[idx] = block + (uint32_t)((ptoa(idx) + esize - 1) / esize);
+ }
+ }
+}
+
+static void
+ztMemoryRemove(zone_t zone, vm_offset_t mem, vm_size_t size)
+{
+ uint32_t * tagbase;
+ uint32_t count, block, blocks, idx;
+ size_t pages;
+
+ // set tag base for each page
+ pages = atop(size);
+ tagbase = ZTAGBASE(zone, mem);
+ block = tagbase[0];
+ for (idx = 0; idx < pages; idx++) {
+ tagbase[idx] = 0xFFFFFFFF;
+ }
+
+ lck_mtx_lock(&ztLock);
+ if (!zone->tags_inline) {
+ count = (uint32_t)(size / zone_elem_size(zone));
+ blocks = ((count + ztTagsPerBlock - 1) / ztTagsPerBlock);
+ assert(block != 0xFFFFFFFF);
+ block /= ztTagsPerBlock;
+ ztFree(NULL /* zone is unlocked */, block, blocks);
+ }
+
+ lck_mtx_unlock(&ztLock);
+}
+
+uint32_t
+zone_index_from_tag_index(uint32_t tag_zone_index, vm_size_t * elem_size)
+{
+ simple_lock(&all_zones_lock, &zone_locks_grp);
+
+ zone_index_foreach(idx) {
+ zone_t z = &zone_array[idx];
+ if (!z->tags) {
+ continue;
+ }
+ if (tag_zone_index != z->tag_zone_index) {
+ continue;
+ }
+
+ *elem_size = zone_elem_size(z);
+ simple_unlock(&all_zones_lock);
+ return idx;
+ }
+
+ simple_unlock(&all_zones_lock);
+
+ return -1U;
+}
+
+#endif /* VM_MAX_TAG_ZONES */
+#endif /* !ZALLOC_TEST */
+#pragma mark zalloc helpers
+#if !ZALLOC_TEST
+
+__pure2
+static inline uint16_t
+zc_mag_size(void)
+{
+ return zc_magazine_size;
+}
+
+__attribute__((noinline, cold))
+static void
+zone_lock_was_contended(zone_t zone, zone_cache_t zc)
+{
+ lck_spin_lock_nopreempt(&zone->z_lock);
+
+ /*
+ * If zone caching has been disabled due to memory pressure,
+ * then recording contention is not useful, give the system
+ * time to recover.
+ */
+ if (__improbable(zone_caching_disabled)) {
+ return;
+ }
+
+ zone->z_contention_cur++;
+
+ if (zc == NULL || zc->zc_depot_max >= INT16_MAX * zc_mag_size()) {
+ return;
+ }
+
+ /*
+ * Let the depot grow based on how bad the contention is,
+ * and how populated the zone is.
+ */
+ if (zone->z_contention_wma < 2 * Z_CONTENTION_WMA_UNIT) {
+ if (zc->zc_depot_max * zpercpu_count() * 20u >=
+ zone->z_elems_avail) {
+ return;
+ }
+ }
+ if (zone->z_contention_wma < 4 * Z_CONTENTION_WMA_UNIT) {
+ if (zc->zc_depot_max * zpercpu_count() * 10u >=
+ zone->z_elems_avail) {
+ return;
+ }
+ }
+ if (!zc_grow_threshold || zone->z_contention_wma <
+ zc_grow_threshold * Z_CONTENTION_WMA_UNIT) {
+ return;
+ }
+
+ zc->zc_depot_max++;
+}
+
+static inline void
+zone_lock_nopreempt_check_contention(zone_t zone, zone_cache_t zc)
+{
+ if (lck_spin_try_lock_nopreempt(&zone->z_lock)) {
+ return;
+ }
+
+ zone_lock_was_contended(zone, zc);
+}
+
+static inline void
+zone_lock_check_contention(zone_t zone, zone_cache_t zc)
+{
+ disable_preemption();
+ zone_lock_nopreempt_check_contention(zone, zc);
+}
+
+static inline void
+zone_unlock_nopreempt(zone_t zone)
+{
+ lck_spin_unlock_nopreempt(&zone->z_lock);
+}
+
+static inline void
+zone_depot_lock_nopreempt(zone_cache_t zc)
+{
+ hw_lock_bit_nopreempt(&zc->zc_depot_lock, 0, &zone_locks_grp);
+}
+
+static inline void
+zone_depot_unlock_nopreempt(zone_cache_t zc)
+{
+ hw_unlock_bit_nopreempt(&zc->zc_depot_lock, 0);
+}
+
+static inline void
+zone_depot_lock(zone_cache_t zc)
+{
+ hw_lock_bit(&zc->zc_depot_lock, 0, &zone_locks_grp);
+}
+
+static inline void
+zone_depot_unlock(zone_cache_t zc)
+{
+ hw_unlock_bit(&zc->zc_depot_lock, 0);
+}
+
+const char *
+zone_name(zone_t z)
+{
+ return z->z_name;
+}
+
+const char *
+zone_heap_name(zone_t z)
+{
+ if (__probable(z->kalloc_heap < KHEAP_ID_COUNT)) {
+ return kalloc_heap_names[z->kalloc_heap];
+ }
+ return "invalid";
+}
+
+static uint32_t
+zone_alloc_pages_for_nelems(zone_t z, vm_size_t max_elems)
+{
+ vm_size_t elem_count, chunks;
+
+ elem_count = ptoa(z->z_percpu ? 1 : z->z_chunk_pages) / zone_elem_size(z);
+ chunks = (max_elems + elem_count - 1) / elem_count;
+
+ return (uint32_t)MIN(UINT32_MAX, chunks * z->z_chunk_pages);
+}
+
+static inline vm_size_t
+zone_submaps_approx_size(void)
+{
+ vm_size_t size = 0;
+
+ for (unsigned idx = 0; idx <= zone_last_submap_idx; idx++) {
+ size += zone_submaps[idx]->size;
+ }
+
+ return size;
+}
+
+static void
+zone_cache_swap_magazines(zone_cache_t cache)
+{
+ uint16_t count_a = cache->zc_alloc_cur;
+ uint16_t count_f = cache->zc_free_cur;
+ zone_element_t *elems_a = cache->zc_alloc_elems;
+ zone_element_t *elems_f = cache->zc_free_elems;
+
+ z_debug_assert(count_a <= zc_mag_size());
+ z_debug_assert(count_f <= zc_mag_size());
+
+ cache->zc_alloc_cur = count_f;
+ cache->zc_free_cur = count_a;
+ cache->zc_alloc_elems = elems_f;
+ cache->zc_free_elems = elems_a;
+}
+
+/*!
+ * @function zone_magazine_load
+ *
+ * @brief
+ * Cache the value of @c zm_cur on the cache to avoid a dependent load
+ * on the allocation fastpath.
+ */
+static void
+zone_magazine_load(uint16_t *count, zone_element_t **elems, zone_magazine_t mag)
+{
+ z_debug_assert(mag->zm_cur <= zc_mag_size());
+ *count = mag->zm_cur;
+ *elems = mag->zm_elems;
+}
+
+/*!
+ * @function zone_magazine_replace
+ *
+ * @brief
+ * Unlod a magazine and load a new one instead.
+ */
+static zone_magazine_t
+zone_magazine_replace(uint16_t *count, zone_element_t **elems,
+ zone_magazine_t mag)
+{
+ zone_magazine_t old;
+
+ old = (zone_magazine_t)((uintptr_t)*elems -
+ offsetof(struct zone_magazine, zm_elems));
+ old->zm_cur = *count;
+ z_debug_assert(old->zm_cur <= zc_mag_size());
+ zone_magazine_load(count, elems, mag);
+
+ return old;
+}
+
+static zone_magazine_t
+zone_magazine_alloc(zalloc_flags_t flags)
+{
+ return zalloc_ext(zc_magazine_zone, zc_magazine_zone->z_stats,
+ flags | Z_ZERO);
+}
+
+static void
+zone_magazine_free(zone_magazine_t mag)
+{
+ zfree_ext(zc_magazine_zone, zc_magazine_zone->z_stats, mag);
+}
+
+static void
+zone_enable_caching(zone_t zone)
+{
+ zone_cache_t caches;
+
+ caches = zalloc_percpu_permanent_type(struct zone_cache);
+ zpercpu_foreach(zc, caches) {
+ zone_magazine_load(&zc->zc_alloc_cur, &zc->zc_alloc_elems,
+ zone_magazine_alloc(Z_WAITOK | Z_NOFAIL));
+ zone_magazine_load(&zc->zc_free_cur, &zc->zc_free_elems,
+ zone_magazine_alloc(Z_WAITOK | Z_NOFAIL));
+ STAILQ_INIT(&zc->zc_depot);
+ }
+
+ if (os_atomic_xchg(&zone->z_pcpu_cache, caches, release)) {
+ panic("allocating caches for zone %s twice", zone->z_name);
+ }
+}
+
+bool
+zone_maps_owned(vm_address_t addr, vm_size_t size)
+{
+ return from_zone_map(addr, size, ZONE_ADDR_NATIVE);
+}
+
+void
+zone_map_sizes(
+ vm_map_size_t *psize,
+ vm_map_size_t *pfree,
+ vm_map_size_t *plargest_free)
+{
+ vm_map_size_t size, free, largest;
+
+ vm_map_sizes(zone_submaps[0], psize, pfree, plargest_free);
+
+ for (uint32_t i = 1; i <= zone_last_submap_idx; i++) {
+ vm_map_sizes(zone_submaps[i], &size, &free, &largest);
+ *psize += size;
+ *pfree += free;
+ *plargest_free = MAX(*plargest_free, largest);
+ }
+}
+
+__attribute__((always_inline))
+vm_map_t
+zone_submap(zone_t zone)
+{
+ return zone_submaps[zone->z_submap_idx];
+}
+
+unsigned
+zpercpu_count(void)
+{
+ return zpercpu_early_count;
+}
+
+int
+track_this_zone(const char *zonename, const char *logname)
+{
+ unsigned int len;
+ const char *zc = zonename;
+ const char *lc = logname;
+
+ /*
+ * Compare the strings. We bound the compare by MAX_ZONE_NAME.
+ */
+
+ for (len = 1; len <= MAX_ZONE_NAME; zc++, lc++, len++) {
+ /*
+ * If the current characters don't match, check for a space in
+ * in the zone name and a corresponding period in the log name.
+ * If that's not there, then the strings don't match.
+ */
+
+ if (*zc != *lc && !(*zc == ' ' && *lc == '.')) {
+ break;
+ }
+
+ /*
+ * The strings are equal so far. If we're at the end, then it's a match.
+ */
+
+ if (*zc == '\0') {
+ return TRUE;
+ }
+ }
+
+ return FALSE;
+}
+
+#if DEBUG || DEVELOPMENT
+
+vm_size_t
+zone_element_info(void *addr, vm_tag_t * ptag)
+{
+ vm_size_t size = 0;
+ vm_tag_t tag = VM_KERN_MEMORY_NONE;
+ struct zone *src_zone;
+
+ if (from_zone_map(addr, sizeof(void *), ZONE_ADDR_NATIVE) ||
+ from_zone_map(addr, sizeof(void *), ZONE_ADDR_FOREIGN)) {
+ src_zone = &zone_array[zone_index_from_ptr(addr)];
+#if VM_MAX_TAG_ZONES
+ if (__improbable(src_zone->tags)) {
+ tag = *ztSlot(src_zone, (vm_offset_t)addr) >> 1;
+ }
+#endif /* VM_MAX_TAG_ZONES */
+ size = zone_elem_size(src_zone);
+ } else {
+#if CONFIG_GZALLOC
+ gzalloc_element_size(addr, NULL, &size);
+#endif /* CONFIG_GZALLOC */
+ }
+ *ptag = tag;
+ return size;
+}
+
+#endif /* DEBUG || DEVELOPMENT */
+
+/* The backup pointer is stored in the last pointer-sized location in an element. */
+__header_always_inline vm_offset_t *
+get_primary_ptr(vm_offset_t elem)
+{
+ return (vm_offset_t *)elem;
+}
+
+__header_always_inline vm_offset_t *
+get_backup_ptr(vm_offset_t elem, vm_size_t elem_size)
+{
+ return (vm_offset_t *)(elem + elem_size - sizeof(vm_offset_t));
+}
+
+#endif /* !ZALLOC_TEST */
+#pragma mark Zone poisoning/zeroing and early random
+#if !ZALLOC_TEST
+
+#define ZONE_ENTROPY_CNT 2
+static struct zone_bool_gen {
+ struct bool_gen zbg_bg;
+ uint32_t zbg_entropy[ZONE_ENTROPY_CNT];
+} zone_bool_gen[MAX_CPUS];
+
+/*
+ * Initialize zone poisoning
+ * called from zone_bootstrap before any allocations are made from zalloc
+ */
+__startup_func
+static void
+zp_bootstrap(void)
+{
+ char temp_buf[16];
+
+ /*
+ * Initialize canary random cookie.
+ *
+ * Make sure that (zp_canary ^ pointer) have non zero low bits (01)
+ * different from ZONE_POISON (11).
+ *
+ * On LP64, have (zp_canary ^ pointer) have the high bits equal 0xC0FFEE...
+ */
+ static_assert(ZONE_POISON % 4 == 3);
+ zp_canary = (uintptr_t)early_random();
+#if __LP64__
+ zp_canary &= 0x000000fffffffffc;
+ zp_canary |= 0xc0ffee0000000001 ^ 0xffffff0000000000;
+#else
+ zp_canary &= 0xfffffffc;
+ zp_canary |= 0x00000001;
+#endif
+
+ /* -zp: enable poisoning for every alloc and free */
+ if (PE_parse_boot_argn("-zp", temp_buf, sizeof(temp_buf))) {
+ zp_factor = 1;
+ }
+
+ /* -no-zp: disable poisoning */
+ if (PE_parse_boot_argn("-no-zp", temp_buf, sizeof(temp_buf))) {
+ zp_factor = 0;
+ printf("Zone poisoning disabled\n");
+ }
+
+ zpercpu_foreach_cpu(cpu) {
+ random_bool_init(&zone_bool_gen[cpu].zbg_bg);
+ }
+}
+
+static inline uint32_t
+zone_poison_count_init(zone_t zone)
+{
+ return zp_factor + (((uint32_t)zone_elem_size(zone)) >> zp_scale) ^
+ (mach_absolute_time() & 0x7);
+}
+
+/*
+ * Zero the element if zone has z_free_zeroes flag set else poison
+ * the element if zs_poison_seqno hits 0.
+ */
+static zprot_mode_t
+zfree_clear_or_poison(zone_t zone, vm_offset_t addr, vm_offset_t elem_size)
+{
+ if (zone->z_free_zeroes) {
+ if (zone->z_percpu) {
+ zpercpu_foreach_cpu(i) {
+ bzero((void *)(addr + ptoa(i)), elem_size);
+ }
+ } else {
+ bzero((void *)addr, elem_size);
+ }
+ return ZPM_ZERO;
+ }
+
+ zprot_mode_t poison = ZPM_AUTO;
+#if ZALLOC_ENABLE_POISONING
+ if (__improbable(zp_factor == 1)) {
+ poison = ZPM_POISON;
+ } else if (__probable(zp_factor != 0)) {
+ uint32_t *seqnop = &zpercpu_get(zone->z_stats)->zs_poison_seqno;
+ uint32_t seqno = os_atomic_load(seqnop, relaxed);
+ if (seqno == 0) {
+ os_atomic_store(seqnop, zone_poison_count_init(zone), relaxed);
+ poison = ZPM_POISON;
+ } else {
+ os_atomic_store(seqnop, seqno - 1, relaxed);
+ }
+ }
+ if (poison == ZPM_POISON) {
+ /* memset_pattern{4|8} could help make this faster: <rdar://problem/4662004> */
+ for (size_t i = 0; i < elem_size / sizeof(vm_offset_t); i++) {
+ ((vm_offset_t *)addr)[i] = ZONE_POISON;
+ }
+ } else {
+ /*
+ * Set a canary at the extremities.
+ *
+ * Zero first zp_min_size bytes of elements that aren't being
+ * poisoned.
+ *
+ * Element size is larger than zp_min_size in this path,
+ * zones with smaller elements have z_free_zeroes set.
+ */
+ *get_primary_ptr(addr) = zp_canary ^ (uintptr_t)addr;
+ bzero((void *)addr + sizeof(vm_offset_t),
+ zp_min_size - sizeof(vm_offset_t));
+ *get_backup_ptr(addr, elem_size) = zp_canary ^ (uintptr_t)addr;
+
+ poison = ZPM_CANARY;
+ }
+#endif /* ZALLOC_ENABLE_POISONING */
+
+ return poison;
+}
+
+#if ZALLOC_ENABLE_POISONING
+
+__abortlike
+static void
+zalloc_uaf_panic(zone_t z, uintptr_t elem, size_t size, zprot_mode_t zpm)
+{
+ uint32_t esize = (uint32_t)zone_elem_size(z);
+ uint32_t first_offs = ~0u;
+ uintptr_t first_bits = 0, v;
+ char buf[1024];
+ int pos = 0;
+ const char *how;
+
+#if __LP64__
+#define ZPF "0x%016lx"
+#else
+#define ZPF "0x%08lx"
+#endif
+
+ buf[0] = '\0';
+
+ if (zpm == ZPM_CANARY) {
+ how = "canaries";
+
+ v = *get_primary_ptr(elem);
+ if (v != (elem ^ zp_canary)) {
+ pos += scnprintf(buf + pos, sizeof(buf) - pos, "\n"
+ "%5d: got "ZPF", want "ZPF" (xor: "ZPF")",
+ 0, v, (elem ^ zp_canary), (v ^ elem ^ zp_canary));
+ if (first_offs > 0) {
+ first_offs = 0;
+ first_bits = v;
+ }
+ }
+
+ v = *get_backup_ptr(elem, esize);
+ if (v != (elem ^ zp_canary)) {
+ pos += scnprintf(buf + pos, sizeof(buf) - pos, "\n"
+ "%5d: got "ZPF", want "ZPF" (xor: "ZPF")",
+ esize - (int)sizeof(v), v, (elem ^ zp_canary),
+ (v ^ elem ^ zp_canary));
+ if (first_offs > esize - sizeof(v)) {
+ first_offs = esize - sizeof(v);
+ first_bits = v;
+ }
+ }
+
+ for (uint32_t o = sizeof(v); o < zp_min_size; o += sizeof(v)) {
+ if ((v = *(uintptr_t *)(elem + o)) == 0) {
+ continue;
+ }
+ pos += scnprintf(buf + pos, sizeof(buf) - pos, "\n"
+ "%5d: "ZPF, o, v);
+ if (first_offs > o) {
+ first_offs = o;
+ first_bits = v;
+ }
+ }
+ } else if (zpm == ZPM_ZERO) {
+ how = "zero";
+
+ for (uint32_t o = 0; o < size; o += sizeof(v)) {
+ if ((v = *(uintptr_t *)(elem + o)) == 0) {
+ continue;
+ }
+ pos += scnprintf(buf + pos, sizeof(buf) - pos, "\n"
+ "%5d: "ZPF, o, v);
+ if (first_offs > o) {
+ first_offs = o;
+ first_bits = v;
+ }
+ }
+ } else {
+ how = "poison";
+
+ for (uint32_t o = 0; o < size; o += sizeof(v)) {
+ if ((v = *(uintptr_t *)(elem + o)) == ZONE_POISON) {
+ continue;
+ }
+ pos += scnprintf(buf + pos, sizeof(buf) - pos, "\n"
+ "%5d: "ZPF" (xor: "ZPF")",
+ o, v, (v ^ ZONE_POISON));
+ if (first_offs > o) {
+ first_offs = o;
+ first_bits = v;
+ }
+ }
+ }
+
+ (panic)("[%s%s]: element modified after free "
+ "(off:%d, val:"ZPF", sz:%d, ptr:%p, prot:%s)%s",
+ zone_heap_name(z), zone_name(z),
+ first_offs, first_bits, esize, (void *)elem, how, buf);
+
+#undef ZPF
+}
+
+static void
+zalloc_validate_element_zero(zone_t zone, vm_offset_t elem, vm_size_t size)
+{
+ if (memcmp_zero_ptr_aligned((void *)elem, size)) {
+ zalloc_uaf_panic(zone, elem, size, ZPM_ZERO);
+ }
+ if (!zone->z_percpu) {
+ return;
+ }
+ for (size_t i = zpercpu_count(); --i > 0;) {
+ elem += PAGE_SIZE;
+ if (memcmp_zero_ptr_aligned((void *)elem, size)) {
+ zalloc_uaf_panic(zone, elem, size, ZPM_ZERO);
+ }
+ }
+}
+
+#if __arm64__ || __arm__
+typedef __attribute__((ext_vector_type(2))) vm_offset_t zpair_t;
+#else
+typedef struct {
+ vm_offset_t x;
+ vm_offset_t y;
+} zpair_t;
+#endif
+
+
+__attribute__((noinline))
+static void
+zalloc_validate_element_poison(zone_t zone, vm_offset_t elem, vm_size_t size)
+{
+ vm_offset_t p = elem;
+ vm_offset_t end = elem + size;
+
+ const zpair_t poison = { ZONE_POISON, ZONE_POISON };
+ zpair_t a, b;
+
+ a.x = *(const vm_offset_t *)p;
+ a.y = *(const vm_offset_t *)(end - sizeof(vm_offset_t));
+
+ a.x ^= poison.x;
+ a.y ^= poison.y;
+
+ /*
+ * align p to the next double-wide boundary
+ * align end to the previous double-wide boundary
+ */
+ p = (p + sizeof(zpair_t) - 1) & -sizeof(zpair_t);
+ end &= -sizeof(zpair_t);
+
+ if ((end - p) % (2 * sizeof(zpair_t)) == 0) {
+ b.y = 0;
+ b.y = 0;
+ } else {
+ end -= sizeof(zpair_t);
+ b.x = ((zpair_t *)end)[0].x ^ poison.x;
+ b.y = ((zpair_t *)end)[0].y ^ poison.y;
+ }
+
+ for (; p < end; p += 2 * sizeof(zpair_t)) {
+ a.x |= ((zpair_t *)p)[0].x ^ poison.x;
+ a.y |= ((zpair_t *)p)[0].y ^ poison.y;
+ b.x |= ((zpair_t *)p)[1].x ^ poison.x;
+ b.y |= ((zpair_t *)p)[1].y ^ poison.y;
+ }
+
+ a.x |= b.x;
+ a.y |= b.y;
+
+ if (a.x || a.y) {
+ zalloc_uaf_panic(zone, elem, size, ZPM_POISON);
+ }
+}
+
+static void
+zalloc_validate_element(zone_t zone, vm_offset_t elem, vm_size_t size,
+ zprot_mode_t zpm)
+{
+ vm_offset_t *primary = get_primary_ptr(elem);
+ vm_offset_t *backup = get_backup_ptr(elem, size);
+
+#if CONFIG_GZALLOC
+ if (zone->gzalloc_tracked) {
+ return;
+ }
+#endif /* CONFIG_GZALLOC */
+
+ if (zone->z_free_zeroes) {
+ return zalloc_validate_element_zero(zone, elem, size);
+ }
+
+ switch (zpm) {
+ case ZPM_AUTO:
+ if (*backup == 0) {
+ size -= sizeof(vm_size_t);
+ return zalloc_validate_element_zero(zone, elem, size);
+ }
+ if (*backup == ZONE_POISON) {
+ size -= sizeof(vm_size_t);
+ return zalloc_validate_element_poison(zone, elem, size);
+ }
+ OS_FALLTHROUGH;
+
+ case ZPM_CANARY:
+ if ((*primary ^ zp_canary) != elem || (*backup ^ zp_canary) != elem) {
+ zalloc_uaf_panic(zone, elem, size, ZPM_CANARY);
+ }
+ *primary = *backup = 0;
+ size = zp_min_size;
+ OS_FALLTHROUGH;
+
+ case ZPM_ZERO:
+ return zalloc_validate_element_zero(zone, elem, size);
+
+ case ZPM_POISON:
+ return zalloc_validate_element_poison(zone, elem, size);
+ }
+}
+
+#endif /* ZALLOC_ENABLE_POISONING */
+#if ZALLOC_EARLY_GAPS
+
+__attribute__((noinline))
+static void
+zone_early_gap_drop(int n)
+{
+ while (n-- > 0) {
+ zone_t zone0 = &zone_array[0];
+ struct zone_page_metadata *meta = NULL;
+ vm_offset_t addr;
+ uint16_t pages;
+ vm_map_t map;
+
+ lck_mtx_lock(&zone_metadata_region_lck);
+
+ if (!zone_pva_is_null(zone0->z_pageq_va)) {
+ meta = zone_meta_queue_pop_native(zone0,
+ &zone0->z_pageq_va, &addr);
+ map = zone_submaps[meta->zm_chunk_len];
+ pages = meta->zm_alloc_size;
+ __builtin_bzero(meta, sizeof(struct zone_page_metadata));
+ }
+
+ lck_mtx_unlock(&zone_metadata_region_lck);
+
+ if (!meta) {
+ break;
+ }
+
+ kmem_free(map, addr, ptoa(pages));
+ }
+}
+
+static void
+zone_early_gap_add(zone_t z, uint16_t pages)
+{
+ struct zone_page_metadata *meta = NULL;
+ zone_t zone0 = &zone_array[0];
+ kern_return_t kr;
+ vm_offset_t addr;
+
+ kma_flags_t kmaflags = KMA_KOBJECT | KMA_ZERO | KMA_VAONLY;
+ if (z->z_submap_idx == Z_SUBMAP_IDX_GENERAL &&
+ z->kalloc_heap != KHEAP_ID_NONE) {
+ kmaflags |= KMA_KHEAP;
+ }
+
+ kr = kernel_memory_allocate(zone_submap(z), &addr, ptoa(pages), 0,
+ kmaflags, VM_KERN_MEMORY_ZONE);
+
+ if (kr != KERN_SUCCESS) {
+ panic("unable to allocate early gap (%d pages): %d", pages, kr);
+ }
+
+ zone_meta_populate(addr, ptoa(pages));
+
+ meta = zone_meta_from_addr(addr);
+ meta->zm_alloc_size = pages;
+ meta->zm_chunk_len = z->z_submap_idx;
+
+ lck_mtx_lock(&zone_metadata_region_lck);
+ zone_meta_queue_push(zone0, &zone0->z_pageq_va, meta);
+ lck_mtx_unlock(&zone_metadata_region_lck);
+}
+
+/*
+ * Roughly until pd1 is made, introduce random gaps
+ * between allocated pages.
+ *
+ * This way the early boot allocations are not in a completely
+ * predictible order and relative position.
+ *
+ * Those gaps are returned to the maps afterwards.
+ *
+ * We abuse the zone 0 (which is unused) "va" pageq to remember
+ * those ranges.
+ */
+__attribute__((noinline))
+static void
+zone_allocate_random_early_gap(zone_t z)
+{
+ int16_t pages = early_random() % 16;
+
+ /*
+ * 6% of the time: drop 2 gaps
+ * 25% of the time: drop 1 gap
+ * 37% of the time: do nothing
+ * 18% of the time: add 1 gap
+ * 12% of the time: add 2 gaps
+ */
+ if (pages > 10) {
+ zone_early_gap_drop(pages == 15 ? 2 : 1);
+ }
+ if (pages < 5) {
+ /* values are 6 through 16 */
+ zone_early_gap_add(z, 6 + 2 * pages);
+ }
+ if (pages < 2) {
+ zone_early_gap_add(z, 6 + early_random() % 16);
+ }
+}
+
+static inline void
+zone_cleanup_early_gaps_if_needed(void)
+{
+ if (__improbable(!zone_pva_is_null(zone_array[0].z_pageq_va))) {
+ zone_early_gap_drop(10);
+ }
+}
+
+#endif /* ZALLOC_EARLY_GAPS */
+
+static void
+zone_early_scramble_rr(zone_t zone, zone_stats_t zstats)
+{
+ int cpu = cpu_number();
+ zone_stats_t zs = zpercpu_get_cpu(zstats, cpu);
+ uint32_t bits;
+
+ bits = random_bool_gen_bits(&zone_bool_gen[cpu].zbg_bg,
+ zone_bool_gen[cpu].zbg_entropy, ZONE_ENTROPY_CNT, 8);
+
+ zs->zs_alloc_rr += bits;
+ zs->zs_alloc_rr %= zone->z_chunk_elems;
+}
+
+#endif /* !ZALLOC_TEST */
+#pragma mark Zone Leak Detection
+#if !ZALLOC_TEST
+
+/*
+ * Zone leak debugging code
+ *
+ * When enabled, this code keeps a log to track allocations to a particular zone that have not
+ * yet been freed. Examining this log will reveal the source of a zone leak. The log is allocated
+ * only when logging is enabled, so there is no effect on the system when it's turned off. Logging is
+ * off by default.
+ *
+ * Enable the logging via the boot-args. Add the parameter "zlog=<zone>" to boot-args where <zone>
+ * is the name of the zone you wish to log.
+ *
+ * This code only tracks one zone, so you need to identify which one is leaking first.
+ * Generally, you'll know you have a leak when you get a "zalloc retry failed 3" panic from the zone
+ * garbage collector. Note that the zone name printed in the panic message is not necessarily the one
+ * containing the leak. So do a zprint from gdb and locate the zone with the bloated size. This
+ * is most likely the problem zone, so set zlog in boot-args to this zone name, reboot and re-run the test. The
+ * next time it panics with this message, examine the log using the kgmacros zstack, findoldest and countpcs.
+ * See the help in the kgmacros for usage info.
+ *
+ *
+ * Zone corruption logging
+ *
+ * Logging can also be used to help identify the source of a zone corruption. First, identify the zone
+ * that is being corrupted, then add "-zc zlog=<zone name>" to the boot-args. When -zc is used in conjunction
+ * with zlog, it changes the logging style to track both allocations and frees to the zone. So when the
+ * corruption is detected, examining the log will show you the stack traces of the callers who last allocated
+ * and freed any particular element in the zone. Use the findelem kgmacro with the address of the element that's been
+ * corrupted to examine its history. This should lead to the source of the corruption.
+ */
+
+/* Returns TRUE if we rolled over the counter at factor */
+__header_always_inline bool
+sample_counter(volatile uint32_t *count_p, uint32_t factor)
+{
+ uint32_t old_count, new_count = 0;
+ if (count_p != NULL) {
+ os_atomic_rmw_loop(count_p, old_count, new_count, relaxed, {
+ new_count = old_count + 1;
+ if (new_count >= factor) {
+ new_count = 0;
+ }
+ });
+ }
+
+ return new_count == 0;
+}
+
+#if ZONE_ENABLE_LOGGING
+/* Log allocations and frees to help debug a zone element corruption */
+static TUNABLE(bool, corruption_debug_flag, "-zc", false);
+
+#define MAX_NUM_ZONES_ALLOWED_LOGGING 10 /* Maximum 10 zones can be logged at once */
+
+static int max_num_zones_to_log = MAX_NUM_ZONES_ALLOWED_LOGGING;
+static int num_zones_logged = 0;
+
+/*
+ * The number of records in the log is configurable via the zrecs parameter in boot-args. Set this to
+ * the number of records you want in the log. For example, "zrecs=10" sets it to 10 records. Since this
+ * is the number of stacks suspected of leaking, we don't need many records.
+ */
+
+#if defined(__LP64__)
+#define ZRECORDS_MAX 2560 /* Max records allowed in the log */
+#else
+#define ZRECORDS_MAX 1536 /* Max records allowed in the log */
+#endif
+#define ZRECORDS_DEFAULT 1024 /* default records in log if zrecs is not specificed in boot-args */
+
+static TUNABLE(uint32_t, log_records, "zrecs", ZRECORDS_DEFAULT);
+
+static void
+zone_enable_logging(zone_t z)
+{
+ z->zlog_btlog = btlog_create(log_records, MAX_ZTRACE_DEPTH,
+ (corruption_debug_flag == FALSE) /* caller_will_remove_entries_for_element? */);
+
+ if (z->zlog_btlog) {
+ printf("zone: logging started for zone %s%s\n",
+ zone_heap_name(z), z->z_name);
+ } else {
+ printf("zone: couldn't allocate memory for zrecords, turning off zleak logging\n");
+ z->zone_logging = false;
+ }
+}
+
+/**
+ * @function zone_setup_logging
+ *
+ * @abstract
+ * Optionally sets up a zone for logging.
+ *
+ * @discussion
+ * We recognized two boot-args:
+ *
+ * zlog=<zone_to_log>
+ * zrecs=<num_records_in_log>
+ *
+ * The zlog arg is used to specify the zone name that should be logged,
+ * and zrecs is used to control the size of the log.
+ *
+ * If zrecs is not specified, a default value is used.
+ */
+static void
+zone_setup_logging(zone_t z)
+{
+ char zone_name[MAX_ZONE_NAME]; /* Temp. buffer for the zone name */
+ char zlog_name[MAX_ZONE_NAME]; /* Temp. buffer to create the strings zlog1, zlog2 etc... */
+ char zlog_val[MAX_ZONE_NAME]; /* the zone name we're logging, if any */
+
+ /*
+ * Don't allow more than ZRECORDS_MAX records even if the user asked for more.
+ *
+ * This prevents accidentally hogging too much kernel memory
+ * and making the system unusable.
+ */
+ if (log_records > ZRECORDS_MAX) {
+ log_records = ZRECORDS_MAX;
+ }
+
+ /*
+ * Append kalloc heap name to zone name (if zone is used by kalloc)
+ */
+ snprintf(zone_name, MAX_ZONE_NAME, "%s%s", zone_heap_name(z), z->z_name);
+
+ /* zlog0 isn't allowed. */
+ for (int i = 1; i <= max_num_zones_to_log; i++) {
+ snprintf(zlog_name, MAX_ZONE_NAME, "zlog%d", i);
+
+ if (PE_parse_boot_argn(zlog_name, zlog_val, sizeof(zlog_val)) &&
+ track_this_zone(zone_name, zlog_val)) {
+ z->zone_logging = true;
+ num_zones_logged++;
+ break;
+ }
+ }
+
+ /*
+ * Backwards compat. with the old boot-arg used to specify single zone
+ * logging i.e. zlog Needs to happen after the newer zlogn checks
+ * because the prefix will match all the zlogn
+ * boot-args.
+ */
+ if (!z->zone_logging &&
+ PE_parse_boot_argn("zlog", zlog_val, sizeof(zlog_val)) &&
+ track_this_zone(zone_name, zlog_val)) {
+ z->zone_logging = true;
+ num_zones_logged++;
+ }
+
+
+ /*
+ * If we want to log a zone, see if we need to allocate buffer space for
+ * the log.
+ *
+ * Some vm related zones are zinit'ed before we can do a kmem_alloc, so
+ * we have to defer allocation in that case.
+ *
+ * zone_init() will finish the job.
+ *
+ * If we want to log one of the VM related zones that's set up early on,
+ * we will skip allocation of the log until zinit is called again later
+ * on some other zone.
+ */
+ if (z->zone_logging && startup_phase >= STARTUP_SUB_KMEM_ALLOC) {
+ zone_enable_logging(z);
+ }
+}
+
+/*
+ * Each record in the log contains a pointer to the zone element it refers to,
+ * and a small array to hold the pc's from the stack trace. A
+ * record is added to the log each time a zalloc() is done in the zone_of_interest. For leak debugging,
+ * the record is cleared when a zfree() is done. For corruption debugging, the log tracks both allocs and frees.
+ * If the log fills, old records are replaced as if it were a circular buffer.
+ */
+
+
+/*
+ * Decide if we want to log this zone by doing a string compare between a zone name and the name
+ * of the zone to log. Return true if the strings are equal, false otherwise. Because it's not
+ * possible to include spaces in strings passed in via the boot-args, a period in the logname will
+ * match a space in the zone name.
+ */
+
+/*
+ * Test if we want to log this zalloc/zfree event. We log if this is the zone we're interested in and
+ * the buffer for the records has been allocated.
+ */
+
+#define DO_LOGGING(z) (z->zlog_btlog != NULL)
+#else /* !ZONE_ENABLE_LOGGING */
+#define DO_LOGGING(z) 0
+#endif /* !ZONE_ENABLE_LOGGING */
+#if CONFIG_ZLEAKS
+
+/*
+ * The zone leak detector, abbreviated 'zleak', keeps track of a subset of the currently outstanding
+ * allocations made by the zone allocator. Every zleak_sample_factor allocations in each zone, we capture a
+ * backtrace. Every free, we examine the table and determine if the allocation was being tracked,
+ * and stop tracking it if it was being tracked.
+ *
+ * We track the allocations in the zallocations hash table, which stores the address that was returned from
+ * the zone allocator. Each stored entry in the zallocations table points to an entry in the ztraces table, which
+ * stores the backtrace associated with that allocation. This provides uniquing for the relatively large
+ * backtraces - we don't store them more than once.
+ *
+ * Data collection begins when the zone map is 50% full, and only occurs for zones that are taking up
+ * a large amount of virtual space.
+ */
+#define ZLEAK_STATE_ENABLED 0x01 /* Zone leak monitoring should be turned on if zone_map fills up. */
+#define ZLEAK_STATE_ACTIVE 0x02 /* We are actively collecting traces. */
+#define ZLEAK_STATE_ACTIVATING 0x04 /* Some thread is doing setup; others should move along. */
+#define ZLEAK_STATE_FAILED 0x08 /* Attempt to allocate tables failed. We will not try again. */
+static uint32_t zleak_state = 0; /* State of collection, as above */
+static unsigned int zleak_sample_factor = 1000; /* Allocations per sample attempt */
+
+bool panic_include_ztrace = FALSE; /* Enable zleak logging on panic */
+vm_size_t zleak_global_tracking_threshold; /* Size of zone map at which to start collecting data */
+vm_size_t zleak_per_zone_tracking_threshold; /* Size a zone will have before we will collect data on it */
+
+/*
+ * Counters for allocation statistics.
+ */
+
+/* Times two active records want to occupy the same spot */
+static unsigned int z_alloc_collisions = 0;
+static unsigned int z_trace_collisions = 0;
+
+/* Times a new record lands on a spot previously occupied by a freed allocation */
+static unsigned int z_alloc_overwrites = 0;
+static unsigned int z_trace_overwrites = 0;
+
+/* Times a new alloc or trace is put into the hash table */
+static unsigned int z_alloc_recorded = 0;
+static unsigned int z_trace_recorded = 0;
+
+/* Times zleak_log returned false due to not being able to acquire the lock */
+static unsigned int z_total_conflicts = 0;
+
+/*
+ * Structure for keeping track of an allocation
+ * An allocation bucket is in use if its element is not NULL
+ */
+struct zallocation {
+ uintptr_t za_element; /* the element that was zalloc'ed or zfree'ed, NULL if bucket unused */
+ vm_size_t za_size; /* how much memory did this allocation take up? */
+ uint32_t za_trace_index; /* index into ztraces for backtrace associated with allocation */
+ /* TODO: #if this out */
+ uint32_t za_hit_count; /* for determining effectiveness of hash function */
+};
+
+/* Size must be a power of two for the zhash to be able to just mask off bits instead of mod */
+static uint32_t zleak_alloc_buckets = CONFIG_ZLEAK_ALLOCATION_MAP_NUM;
+static uint32_t zleak_trace_buckets = CONFIG_ZLEAK_TRACE_MAP_NUM;
+
+vm_size_t zleak_max_zonemap_size;
+
+/* Hashmaps of allocations and their corresponding traces */
+static struct zallocation* zallocations;
+static struct ztrace* ztraces;
+
+/* not static so that panic can see this, see kern/debug.c */
+struct ztrace* top_ztrace;
+
+/* Lock to protect zallocations, ztraces, and top_ztrace from concurrent modification. */
+static LCK_GRP_DECLARE(zleak_lock_grp, "zleak_lock");
+static LCK_SPIN_DECLARE(zleak_lock, &zleak_lock_grp);
+
+/*
+ * Initializes the zone leak monitor. Called from zone_init()
+ */
+__startup_func
+static void
+zleak_init(vm_size_t max_zonemap_size)
+{
+ char scratch_buf[16];
+ boolean_t zleak_enable_flag = FALSE;
+
+ zleak_max_zonemap_size = max_zonemap_size;
+ zleak_global_tracking_threshold = max_zonemap_size / 2;
+ zleak_per_zone_tracking_threshold = zleak_global_tracking_threshold / 8;
+
+#if CONFIG_EMBEDDED
+ if (PE_parse_boot_argn("-zleakon", scratch_buf, sizeof(scratch_buf))) {
+ zleak_enable_flag = TRUE;
+ printf("zone leak detection enabled\n");
+ } else {
+ zleak_enable_flag = FALSE;
+ printf("zone leak detection disabled\n");
+ }
+#else /* CONFIG_EMBEDDED */
+ /* -zleakoff (flag to disable zone leak monitor) */
+ if (PE_parse_boot_argn("-zleakoff", scratch_buf, sizeof(scratch_buf))) {
+ zleak_enable_flag = FALSE;
+ printf("zone leak detection disabled\n");
+ } else {
+ zleak_enable_flag = TRUE;
+ printf("zone leak detection enabled\n");
+ }
+#endif /* CONFIG_EMBEDDED */
+
+ /* zfactor=XXXX (override how often to sample the zone allocator) */
+ if (PE_parse_boot_argn("zfactor", &zleak_sample_factor, sizeof(zleak_sample_factor))) {
+ printf("Zone leak factor override: %u\n", zleak_sample_factor);
+ }
+
+ /* zleak-allocs=XXXX (override number of buckets in zallocations) */
+ if (PE_parse_boot_argn("zleak-allocs", &zleak_alloc_buckets, sizeof(zleak_alloc_buckets))) {
+ printf("Zone leak alloc buckets override: %u\n", zleak_alloc_buckets);
+ /* uses 'is power of 2' trick: (0x01000 & 0x00FFF == 0) */
+ if (zleak_alloc_buckets == 0 || (zleak_alloc_buckets & (zleak_alloc_buckets - 1))) {
+ printf("Override isn't a power of two, bad things might happen!\n");
+ }
+ }
+
+ /* zleak-traces=XXXX (override number of buckets in ztraces) */
+ if (PE_parse_boot_argn("zleak-traces", &zleak_trace_buckets, sizeof(zleak_trace_buckets))) {
+ printf("Zone leak trace buckets override: %u\n", zleak_trace_buckets);
+ /* uses 'is power of 2' trick: (0x01000 & 0x00FFF == 0) */
+ if (zleak_trace_buckets == 0 || (zleak_trace_buckets & (zleak_trace_buckets - 1))) {
+ printf("Override isn't a power of two, bad things might happen!\n");
+ }
+ }
+
+ if (zleak_enable_flag) {
+ zleak_state = ZLEAK_STATE_ENABLED;
+ }
+}
+
+/*
+ * Support for kern.zleak.active sysctl - a simplified
+ * version of the zleak_state variable.
+ */
+int
+get_zleak_state(void)
+{
+ if (zleak_state & ZLEAK_STATE_FAILED) {
+ return -1;
+ }
+ if (zleak_state & ZLEAK_STATE_ACTIVE) {
+ return 1;
+ }
+ return 0;
+}
+
+kern_return_t
+zleak_activate(void)
+{
+ kern_return_t retval;
+ vm_size_t z_alloc_size = zleak_alloc_buckets * sizeof(struct zallocation);
+ vm_size_t z_trace_size = zleak_trace_buckets * sizeof(struct ztrace);
+ void *allocations_ptr = NULL;
+ void *traces_ptr = NULL;
+
+ /* Only one thread attempts to activate at a time */
+ if (zleak_state & (ZLEAK_STATE_ACTIVE | ZLEAK_STATE_ACTIVATING | ZLEAK_STATE_FAILED)) {
+ return KERN_SUCCESS;
+ }
+
+ /* Indicate that we're doing the setup */
+ lck_spin_lock(&zleak_lock);
+ if (zleak_state & (ZLEAK_STATE_ACTIVE | ZLEAK_STATE_ACTIVATING | ZLEAK_STATE_FAILED)) {
+ lck_spin_unlock(&zleak_lock);
+ return KERN_SUCCESS;
+ }
+
+ zleak_state |= ZLEAK_STATE_ACTIVATING;
+ lck_spin_unlock(&zleak_lock);
+
+ /* Allocate and zero tables */
+ retval = kmem_alloc_kobject(kernel_map, (vm_offset_t*)&allocations_ptr, z_alloc_size, VM_KERN_MEMORY_DIAG);
+ if (retval != KERN_SUCCESS) {
+ goto fail;
+ }
+
+ retval = kmem_alloc_kobject(kernel_map, (vm_offset_t*)&traces_ptr, z_trace_size, VM_KERN_MEMORY_DIAG);
+ if (retval != KERN_SUCCESS) {
+ goto fail;
+ }
+
+ bzero(allocations_ptr, z_alloc_size);
+ bzero(traces_ptr, z_trace_size);
+
+ /* Everything's set. Install tables, mark active. */
+ zallocations = allocations_ptr;
+ ztraces = traces_ptr;
+
+ /*
+ * Initialize the top_ztrace to the first entry in ztraces,
+ * so we don't have to check for null in zleak_log
+ */
+ top_ztrace = &ztraces[0];
+
+ /*
+ * Note that we do need a barrier between installing
+ * the tables and setting the active flag, because the zfree()
+ * path accesses the table without a lock if we're active.
+ */
+ lck_spin_lock(&zleak_lock);
+ zleak_state |= ZLEAK_STATE_ACTIVE;
+ zleak_state &= ~ZLEAK_STATE_ACTIVATING;
+ lck_spin_unlock(&zleak_lock);
+
+ return 0;
+
+fail:
+ /*
+ * If we fail to allocate memory, don't further tax
+ * the system by trying again.
+ */
+ lck_spin_lock(&zleak_lock);
+ zleak_state |= ZLEAK_STATE_FAILED;
+ zleak_state &= ~ZLEAK_STATE_ACTIVATING;
+ lck_spin_unlock(&zleak_lock);
+
+ if (allocations_ptr != NULL) {
+ kmem_free(kernel_map, (vm_offset_t)allocations_ptr, z_alloc_size);
+ }
+
+ if (traces_ptr != NULL) {
+ kmem_free(kernel_map, (vm_offset_t)traces_ptr, z_trace_size);
+ }
+
+ return retval;
+}
+
+static inline void
+zleak_activate_if_needed(void)
+{
+ if (__probable((zleak_state & ZLEAK_STATE_ENABLED) == 0)) {
+ return;
+ }
+ if (zleak_state & ZLEAK_STATE_ACTIVE) {
+ return;
+ }
+ if (zone_submaps_approx_size() < zleak_global_tracking_threshold) {
+ return;
+ }
+
+ kern_return_t kr = zleak_activate();
+ if (kr != KERN_SUCCESS) {
+ printf("Failed to activate live zone leak debugging (%d).\n", kr);
+ }
+}
+
+static inline void
+zleak_track_if_needed(zone_t z)
+{
+ if (__improbable(zleak_state & ZLEAK_STATE_ACTIVE)) {
+ if (!z->zleak_on &&
+ zone_size_wired(z) >= zleak_per_zone_tracking_threshold) {
+ z->zleak_on = true;
+ }
+ }
+}
+
+/*
+ * TODO: What about allocations that never get deallocated,
+ * especially ones with unique backtraces? Should we wait to record
+ * until after boot has completed?
+ * (How many persistent zallocs are there?)
+ */
+
+/*
+ * This function records the allocation in the allocations table,
+ * and stores the associated backtrace in the traces table
+ * (or just increments the refcount if the trace is already recorded)
+ * If the allocation slot is in use, the old allocation is replaced with the new allocation, and
+ * the associated trace's refcount is decremented.
+ * If the trace slot is in use, it returns.
+ * The refcount is incremented by the amount of memory the allocation consumes.
+ * The return value indicates whether to try again next time.
+ */
+static boolean_t
+zleak_log(uintptr_t* bt,
+ uintptr_t addr,
+ uint32_t depth,
+ vm_size_t allocation_size)
+{
+ /* Quit if there's someone else modifying the hash tables */
+ if (!lck_spin_try_lock(&zleak_lock)) {
+ z_total_conflicts++;
+ return FALSE;
+ }
+
+ struct zallocation* allocation = &zallocations[hashaddr(addr, zleak_alloc_buckets)];
+
+ uint32_t trace_index = hashbacktrace(bt, depth, zleak_trace_buckets);
+ struct ztrace* trace = &ztraces[trace_index];
+
+ allocation->za_hit_count++;
+ trace->zt_hit_count++;
+
+ /*
+ * If the allocation bucket we want to be in is occupied, and if the occupier
+ * has the same trace as us, just bail.
+ */
+ if (allocation->za_element != (uintptr_t) 0 && trace_index == allocation->za_trace_index) {
+ z_alloc_collisions++;
+
+ lck_spin_unlock(&zleak_lock);
+ return TRUE;
+ }
+
+ /* STEP 1: Store the backtrace in the traces array. */
+ /* A size of zero indicates that the trace bucket is free. */
+
+ if (trace->zt_size > 0 && bcmp(trace->zt_stack, bt, (depth * sizeof(uintptr_t))) != 0) {
+ /*
+ * Different unique trace with same hash!
+ * Just bail - if we're trying to record the leaker, hopefully the other trace will be deallocated
+ * and get out of the way for later chances
+ */
+ trace->zt_collisions++;
+ z_trace_collisions++;
+
+ lck_spin_unlock(&zleak_lock);
+ return TRUE;
+ } else if (trace->zt_size > 0) {
+ /* Same trace, already added, so increment refcount */
+ trace->zt_size += allocation_size;
+ } else {
+ /* Found an unused trace bucket, record the trace here! */
+ if (trace->zt_depth != 0) { /* if this slot was previously used but not currently in use */
+ z_trace_overwrites++;
+ }
+
+ z_trace_recorded++;
+ trace->zt_size = allocation_size;
+ memcpy(trace->zt_stack, bt, (depth * sizeof(uintptr_t)));
+
+ trace->zt_depth = depth;
+ trace->zt_collisions = 0;
+ }
+
+ /* STEP 2: Store the allocation record in the allocations array. */
+
+ if (allocation->za_element != (uintptr_t) 0) {
+ /*
+ * Straight up replace any allocation record that was there. We don't want to do the work
+ * to preserve the allocation entries that were there, because we only record a subset of the
+ * allocations anyways.
+ */
+
+ z_alloc_collisions++;
+
+ struct ztrace* associated_trace = &ztraces[allocation->za_trace_index];
+ /* Knock off old allocation's size, not the new allocation */
+ associated_trace->zt_size -= allocation->za_size;
+ } else if (allocation->za_trace_index != 0) {
+ /* Slot previously used but not currently in use */
+ z_alloc_overwrites++;
+ }
+
+ allocation->za_element = addr;
+ allocation->za_trace_index = trace_index;
+ allocation->za_size = allocation_size;
+
+ z_alloc_recorded++;
+
+ if (top_ztrace->zt_size < trace->zt_size) {
+ top_ztrace = trace;
+ }
+
+ lck_spin_unlock(&zleak_lock);
+ return TRUE;
+}
+
+/*
+ * Free the allocation record and release the stacktrace.
+ * This should be as fast as possible because it will be called for every free.
+ */
+__attribute__((noinline))
+static void
+zleak_free(uintptr_t addr,
+ vm_size_t allocation_size)
+{
+ if (addr == (uintptr_t) 0) {
+ return;
+ }
+
+ struct zallocation* allocation = &zallocations[hashaddr(addr, zleak_alloc_buckets)];
+
+ /* Double-checked locking: check to find out if we're interested, lock, check to make
+ * sure it hasn't changed, then modify it, and release the lock.
+ */
+
+ if (allocation->za_element == addr && allocation->za_trace_index < zleak_trace_buckets) {
+ /* if the allocation was the one, grab the lock, check again, then delete it */
+ lck_spin_lock(&zleak_lock);
+
+ if (allocation->za_element == addr && allocation->za_trace_index < zleak_trace_buckets) {
+ struct ztrace *trace;
+
+ /* allocation_size had better match what was passed into zleak_log - otherwise someone is freeing into the wrong zone! */
+ if (allocation->za_size != allocation_size) {
+ panic("Freeing as size %lu memory that was allocated with size %lu\n",
+ (uintptr_t)allocation_size, (uintptr_t)allocation->za_size);
+ }
+
+ trace = &ztraces[allocation->za_trace_index];
+
+ /* size of 0 indicates trace bucket is unused */
+ if (trace->zt_size > 0) {
+ trace->zt_size -= allocation_size;
+ }
+
+ /* A NULL element means the allocation bucket is unused */
+ allocation->za_element = 0;
+ }
+ lck_spin_unlock(&zleak_lock);
+ }
+}
+
+#else
+static inline void
+zleak_activate_if_needed(void)
+{
+}
+
+static inline void
+zleak_track_if_needed(__unused zone_t z)
+{
+}
+#endif /* CONFIG_ZLEAKS */
+#if ZONE_ENABLE_LOGGING || CONFIG_ZLEAKS
+
+__attribute__((noinline))
+static void
+zalloc_log_or_trace_leaks(zone_t zone, vm_offset_t addr, void *fp)
+{
+ uintptr_t zbt[MAX_ZTRACE_DEPTH]; /* used in zone leak logging and zone leak detection */
+ unsigned int numsaved = 0;
+
+#if ZONE_ENABLE_LOGGING
+ if (DO_LOGGING(zone)) {
+ numsaved = backtrace(zbt, MAX_ZTRACE_DEPTH, NULL);
+ btlog_add_entry(zone->zlog_btlog, (void *)addr,
+ ZOP_ALLOC, (void **)zbt, numsaved);
+ }
+#endif /* ZONE_ENABLE_LOGGING */
+
+#if CONFIG_ZLEAKS
+ /*
+ * Zone leak detection: capture a backtrace every zleak_sample_factor
+ * allocations in this zone.
+ */
+ if (__improbable(zone->zleak_on)) {
+ if (sample_counter(&zone->zleak_capture, zleak_sample_factor)) {
+ /* Avoid backtracing twice if zone logging is on */
+ if (numsaved == 0) {
+ numsaved = backtrace_frame(zbt, MAX_ZTRACE_DEPTH, fp, NULL);
+ }
+ /* Sampling can fail if another sample is happening at the same time in a different zone. */
+ if (!zleak_log(zbt, addr, numsaved, zone_elem_size(zone))) {
+ /* If it failed, roll back the counter so we sample the next allocation instead. */
+ zone->zleak_capture = zleak_sample_factor;
+ }
+ }
+ }
+
+ if (__improbable(zone_leaks_scan_enable &&
+ !(zone_elem_size(zone) & (sizeof(uintptr_t) - 1)))) {
+ unsigned int count, idx;
+ /* Fill element, from tail, with backtrace in reverse order */
+ if (numsaved == 0) {
+ numsaved = backtrace_frame(zbt, MAX_ZTRACE_DEPTH, fp, NULL);
+ }
+ count = (unsigned int)(zone_elem_size(zone) / sizeof(uintptr_t));
+ if (count >= numsaved) {
+ count = numsaved - 1;
+ }
+ for (idx = 0; idx < count; idx++) {
+ ((uintptr_t *)addr)[count - 1 - idx] = zbt[idx + 1];
+ }
+ }
+#endif /* CONFIG_ZLEAKS */
+}
+
+static inline bool
+zalloc_should_log_or_trace_leaks(zone_t zone, vm_size_t elem_size)
+{
+#if ZONE_ENABLE_LOGGING
+ if (DO_LOGGING(zone)) {
+ return true;
+ }
+#endif /* ZONE_ENABLE_LOGGING */
+#if CONFIG_ZLEAKS
+ /*
+ * Zone leak detection: capture a backtrace every zleak_sample_factor
+ * allocations in this zone.
+ */
+ if (zone->zleak_on) {
+ return true;
+ }
+ if (zone_leaks_scan_enable && !(elem_size & (sizeof(uintptr_t) - 1))) {
+ return true;
+ }
+#endif /* CONFIG_ZLEAKS */
+ return false;
+}
+
+#endif /* ZONE_ENABLE_LOGGING || CONFIG_ZLEAKS */
+#if ZONE_ENABLE_LOGGING
+
+__attribute__((noinline))
+static void
+zfree_log_trace(zone_t zone, vm_offset_t addr, void *fp)
+{
+ /*
+ * See if we're doing logging on this zone.
+ *
+ * There are two styles of logging used depending on
+ * whether we're trying to catch a leak or corruption.
+ */
+ if (__improbable(DO_LOGGING(zone))) {
+ if (corruption_debug_flag) {
+ uintptr_t zbt[MAX_ZTRACE_DEPTH];
+ unsigned int numsaved;
+ /*
+ * We're logging to catch a corruption.
+ *
+ * Add a record of this zfree operation to log.
+ */
+ numsaved = backtrace_frame(zbt, MAX_ZTRACE_DEPTH, fp, NULL);
+ btlog_add_entry(zone->zlog_btlog, (void *)addr, ZOP_FREE,
+ (void **)zbt, numsaved);
+ } else {
+ /*
+ * We're logging to catch a leak.
+ *
+ * Remove any record we might have for this element
+ * since it's being freed. Note that we may not find it
+ * if the buffer overflowed and that's OK.
+ *
+ * Since the log is of a limited size, old records get
+ * overwritten if there are more zallocs than zfrees.
+ */
+ btlog_remove_entries_for_element(zone->zlog_btlog, (void *)addr);
+ }
+ }
+}
+
+#endif /* ZONE_ENABLE_LOGGING */
+
+/* These functions outside of CONFIG_ZLEAKS because they are also used in
+ * mbuf.c for mbuf leak-detection. This is why they lack the z_ prefix.
+ */
+
+/* "Thomas Wang's 32/64 bit mix functions." http://www.concentric.net/~Ttwang/tech/inthash.htm */
+uintptr_t
+hash_mix(uintptr_t x)
+{
+#ifndef __LP64__
+ x += ~(x << 15);
+ x ^= (x >> 10);
+ x += (x << 3);
+ x ^= (x >> 6);
+ x += ~(x << 11);
+ x ^= (x >> 16);
+#else
+ x += ~(x << 32);
+ x ^= (x >> 22);
+ x += ~(x << 13);
+ x ^= (x >> 8);
+ x += (x << 3);
+ x ^= (x >> 15);
+ x += ~(x << 27);
+ x ^= (x >> 31);
+#endif
+ return x;
+}
+
+uint32_t
+hashbacktrace(uintptr_t* bt, uint32_t depth, uint32_t max_size)
+{
+ uintptr_t hash = 0;
+ uintptr_t mask = max_size - 1;
+
+ while (depth) {
+ hash += bt[--depth];
+ }
+
+ hash = hash_mix(hash) & mask;
+
+ assert(hash < max_size);
+
+ return (uint32_t) hash;
+}
+
+/*
+ * TODO: Determine how well distributed this is
+ * max_size must be a power of 2. i.e 0x10000 because 0x10000-1 is 0x0FFFF which is a great bitmask
+ */
+uint32_t
+hashaddr(uintptr_t pt, uint32_t max_size)
+{
+ uintptr_t hash = 0;
+ uintptr_t mask = max_size - 1;
+
+ hash = hash_mix(pt) & mask;
+
+ assert(hash < max_size);
+
+ return (uint32_t) hash;
+}
+
+#endif /* !ZALLOC_TEST */
+#pragma mark zone (re)fill
+#if !ZALLOC_TEST
+
+/*!
+ * @defgroup Zone Refill
+ * @{
+ *
+ * @brief
+ * Functions handling The zone refill machinery.
+ *
+ * @discussion
+ * Zones are refilled based on 3 mechanisms: direct expansion, async expansion,
+ * VM-specific replenishment. Zones using VM-specific replenishment are marked
+ * with the @c z_replenishes property set.
+ *
+ * @c zalloc_ext() is the codepath that kicks the zone refill when the zone is
+ * dropping below half of its @c z_elems_rsv (0 for most zones) and will:
+ *
+ * - call @c zone_expand_locked() directly if the caller is allowed to block,
+ *
+ * - wakeup the asynchroous expansion thread call if the caller is not allowed
+ * to block.
+ *
+ * - call @c zone_replenish_locked() to kick the replenish state machine.
+ *
+ *
+ * <h2>Synchronous expansion</h2>
+ *
+ * This mechanism is actually the only one that may refill a zone, and all the
+ * other ones funnel through this one eventually.
+ *
+ * @c zone_expand_locked() implements the core of the expansion mechanism,
+ * and will do so while a caller specified predicate is true.
+ *
+ * Zone expansion allows for up to 2 threads to concurrently refill the zone:
+ * - one VM privileged thread,
+ * - one regular thread.
+ *
+ * Regular threads that refill will put down their identity in @c z_expander,
+ * so that priority inversion avoidance can be implemented.
+ *
+ * However, VM privileged threads are allowed to use VM page reserves,
+ * which allows for the system to recover from extreme memory pressure
+ * situations, allowing for the few allocations that @c zone_gc() or
+ * killing processes require.
+ *
+ * When a VM privileged thread is also expanding, the @c z_expander_vm_priv bit
+ * is set. @c z_expander is not necessarily the identity of this VM privileged
+ * thread (it is if the VM privileged thread came in first, but wouldn't be, and
+ * could even be @c THREAD_NULL otherwise).
+ *
+ * Note that the pageout-scan daemon might be BG and is VM privileged. To avoid
+ * spending a whole pointer on priority inheritance for VM privileged threads
+ * (and other issues related to having two owners), we use the rwlock boost as
+ * a stop gap to avoid priority inversions.
+ *
+ *
+ * <h2>Chunk wiring policies</h2>
+ *
+ * Zones allocate memory in chunks of @c zone_t::z_chunk_pages pages at a time
+ * to try to minimize fragmentation relative to element sizes not aligning with
+ * a chunk size well. However, this can grow large and be hard to fulfill on
+ * a system under a lot of memory pressure (chunks can be as long as 8 pages on
+ * 4k page systems).
+ *
+ * This is why, when under memory pressure the system allows chunks to be
+ * partially populated. The metadata of the first page in the chunk maintains
+ * the count of actually populated pages.
+ *
+ * The metadata for addresses assigned to a zone are found of 4 queues:
+ * - @c z_pageq_empty has chunk heads with populated pages and no allocated
+ * elements (those can be targeted by @c zone_gc()),
+ * - @c z_pageq_partial has chunk heads with populated pages that are partially
+ * used,
+ * - @c z_pageq_full has chunk heads with populated pages with no free elements
+ * left,
+ * - @c z_pageq_va has either chunk heads for sequestered VA space assigned to
+ * the zone forever (if @c z_va_sequester is enabled), or the first secondary
+ * metadata for a chunk whose corresponding page is not populated in the
+ * chunk.
+ *
+ * When new pages need to be wired/populated, chunks from the @c z_pageq_va
+ * queues are preferred.
+ *
+ *
+ * <h2>Asynchronous expansion</h2>
+ *
+ * This mechanism allows for refilling zones used mostly with non blocking
+ * callers. It relies on a thread call (@c zone_expand_callout) which will
+ * iterate all zones and refill the ones marked with @c z_async_refilling.
+ *
+ * NOTE: If the calling thread for zalloc_noblock is lower priority than
+ * the thread_call, then zalloc_noblock to an empty zone may succeed.
+ *
+ *
+ * <h2>Dealing with zone allocations from the mach VM code</h2>
+ *
+ * The implementation of the mach VM itself uses the zone allocator
+ * for things like the vm_map_entry data structure. In order to prevent
+ * an infinite recursion problem when adding more pages to a zone, @c zalloc
+ * uses a replenish thread to refill the VM layer's zones before they have
+ * too few remaining free entries. The reserved remaining free entries
+ * guarantee that the VM routines can get entries from already mapped pages.
+ *
+ * In order for that to work, the amount of allocations in the nested
+ * case have to be bounded. There are currently 2 replenish zones, and
+ * if each needs 1 element of each zone to add a new page to itself, that
+ * gives us a minumum reserve of 2 elements.
+ *
+ * There is also a deadlock issue with the zone garbage collection thread,
+ * or any thread that is trying to free zone pages. While holding
+ * the kernel's map lock they may need to allocate new VM map entries, hence
+ * we need enough reserve to allow them to get past the point of holding the
+ * map lock. After freeing that page, the GC thread will wait in
+ * @c zone_reclaim() until the replenish threads can finish.
+ * Since there's only 1 GC thread at a time, that adds a minimum of 1 to the
+ * reserve size.
+ *
+ * Since the minumum amount you can add to a zone is 1 page,
+ * we'll use 16K (from ARM) as the refill size on all platforms.
+ *
+ * When a refill zone drops to half that available, i.e. REFILL_SIZE / 2,
+ * @c zalloc_ext() will wake the replenish thread. The replenish thread runs
+ * until at least REFILL_SIZE worth of free elements exist, before sleeping again.
+ * In the meantime threads may continue to use the reserve until there are only
+ * REFILL_SIZE / 4 elements left. Below that point only the replenish threads
+ * themselves and the GC thread may continue to use from the reserve.
+ */
+
+static thread_call_data_t zone_expand_callout;
+
+static inline kma_flags_t
+zone_kma_flags(zone_t z, zalloc_flags_t flags)
+{
+ kma_flags_t kmaflags = KMA_KOBJECT | KMA_ZERO;
+
+ if (z->z_noencrypt) {
+ kmaflags |= KMA_NOENCRYPT;
+ }
+ if (flags & Z_NOPAGEWAIT) {
+ kmaflags |= KMA_NOPAGEWAIT;
+ }
+ if (z->z_permanent || (!z->z_destructible && z->z_va_sequester)) {
+ kmaflags |= KMA_PERMANENT;
+ }
+ if (z->z_submap_idx == Z_SUBMAP_IDX_GENERAL &&
+ z->kalloc_heap != KHEAP_ID_NONE) {
+ kmaflags |= KMA_KHEAP;
+ }
+
+ return kmaflags;
+}
+
+/*!
+ * @function zcram_and_lock()
+ *
+ * @brief
+ * Prepare some memory for being usable for allocation purposes.
+ *
+ * @discussion
+ * Prepare memory in <code>[addr + ptoa(pg_start), addr + ptoa(pg_end))</code>
+ * to be usable in the zone.
+ *
+ * This function assumes the metadata is already populated for the range.
+ *
+ * Calling this function with @c pg_start being 0 means that the memory
+ * is either a partial chunk, or a full chunk, that isn't published anywhere
+ * and the initialization can happen without locks held.
+ *
+ * Calling this function with a non zero @c pg_start means that we are extending
+ * an existing chunk: the memory in <code>[addr, addr + ptoa(pg_start))</code>,
+ * is already usable and published in the zone, so extending it requires holding
+ * the zone lock.
+ *
+ * @param zone The zone to cram new populated pages into
+ * @param addr The base address for the chunk(s)
+ * @param pg_va_new The number of virtual pages newly assigned to the zone
+ * @param pg_start The first newly populated page relative to @a addr.
+ * @param pg_end The after-last newly populated page relative to @a addr.
+ * @param kind The kind of memory assigned to the zone.
+ */
+static void
+zcram_and_lock(zone_t zone, vm_offset_t addr, uint32_t pg_va_new,
+ uint32_t pg_start, uint32_t pg_end, zone_addr_kind_t kind)
+{
+ zone_id_t zindex = zone_index(zone);
+ vm_offset_t elem_size = zone_elem_size(zone);
+ uint32_t free_start = 0, free_end = 0;
+
+ struct zone_page_metadata *meta = zone_meta_from_addr(addr);
+ uint32_t chunk_pages = zone->z_chunk_pages;
+
+ assert(pg_start < pg_end && pg_end <= chunk_pages);
+
+ if (pg_start == 0) {
+ uint16_t chunk_len = (uint16_t)pg_end;
+ uint16_t secondary_len = ZM_SECONDARY_PAGE;
+ bool inline_bitmap = false;
+
+ if (zone->z_percpu) {
+ chunk_len = 1;
+ secondary_len = ZM_SECONDARY_PCPU_PAGE;
+ assert(pg_end == zpercpu_count());
+ }
+ if (!zone->z_permanent) {
+ inline_bitmap = zone->z_chunk_elems <= 32 * chunk_pages;
+ }
+
+ meta[0] = (struct zone_page_metadata){
+ .zm_index = zindex,
+ .zm_inline_bitmap = inline_bitmap,
+ .zm_chunk_len = chunk_len,
+ };
+ if (kind == ZONE_ADDR_FOREIGN) {
+ /* Never hit z_pageq_empty */
+ meta[0].zm_alloc_size = ZM_ALLOC_SIZE_LOCK;
+ }
+
+ for (uint16_t i = 1; i < chunk_pages; i++) {
+ meta[i] = (struct zone_page_metadata){
+ .zm_index = zindex,
+ .zm_inline_bitmap = inline_bitmap,
+ .zm_chunk_len = secondary_len,
+ .zm_page_index = i,
+ };
+ }
+
+ free_end = (uint32_t)ptoa(chunk_len) / elem_size;
+ if (!zone->z_permanent) {
+ zone_meta_bits_init(meta, free_end, zone->z_chunk_elems);
+ }
+ } else {
+ assert(!zone->z_percpu && !zone->z_permanent);
+
+ free_end = (uint32_t)ptoa(pg_end) / elem_size;
+ free_start = (uint32_t)ptoa(pg_start) / elem_size;
+ }
+
+#if VM_MAX_TAG_ZONES
+ if (__improbable(zone->tags)) {
+ assert(kind == ZONE_ADDR_NATIVE && !zone->z_percpu);
+ ztMemoryAdd(zone, addr + ptoa(pg_start),
+ ptoa(pg_end - pg_start));
+ }
+#endif /* VM_MAX_TAG_ZONES */
+
+ /*
+ * Insert the initialized pages / metadatas into the right lists.
+ */
+
+ zone_lock(zone);
+ assert(zone->z_self == zone);
+
+ if (pg_start != 0) {
+ assert(meta->zm_chunk_len == pg_start);
+
+ zone_meta_bits_merge(meta, free_start, free_end);
+ meta->zm_chunk_len = (uint16_t)pg_end;
+
+ /*
+ * consume the zone_meta_lock_in_partial()
+ * done in zone_expand_locked()
+ */
+ zone_meta_alloc_size_sub(zone, meta, ZM_ALLOC_SIZE_LOCK);
+ zone_meta_remqueue(zone, meta);
+ }
+
+ if (zone->z_permanent || meta->zm_alloc_size) {
+ zone_meta_queue_push(zone, &zone->z_pageq_partial, meta);
+ } else {
+ zone_meta_queue_push(zone, &zone->z_pageq_empty, meta);
+ zone->z_wired_empty += zone->z_percpu ? 1 : pg_end;
+ }
+ if (pg_end < chunk_pages) {
+ /* push any non populated residual VA on z_pageq_va */
+ zone_meta_queue_push(zone, &zone->z_pageq_va, meta + pg_end);
+ }
+
+ zone_elems_free_add(zone, free_end - free_start);
+ zone->z_elems_avail += free_end - free_start;
+ zone->z_wired_cur += zone->z_percpu ? 1 : pg_end - pg_start;
+ if (pg_va_new) {
+ zone->z_va_cur += zone->z_percpu ? 1 : pg_va_new;
+ }
+ if (zone->z_wired_hwm < zone->z_wired_cur) {
+ zone->z_wired_hwm = zone->z_wired_cur;
+ }
+
+ os_atomic_add(&zones_phys_page_mapped_count, pg_end - pg_start, relaxed);
+}
+
+static void
+zcram(zone_t zone, vm_offset_t addr, uint32_t pages, zone_addr_kind_t kind)
+{
+ uint32_t chunk_pages = zone->z_chunk_pages;
+
+ assert(pages % chunk_pages == 0);
+ for (; pages > 0; pages -= chunk_pages, addr += ptoa(chunk_pages)) {
+ zcram_and_lock(zone, addr, chunk_pages, 0, chunk_pages, kind);
+ zone_unlock(zone);
+ }
+}
+
+void
+zone_cram_foreign(zone_t zone, vm_offset_t newmem, vm_size_t size)
+{
+ uint32_t pages = (uint32_t)atop(size);
+
+ if (!from_zone_map(newmem, size, ZONE_ADDR_FOREIGN)) {
+ panic("zone_cram_foreign: foreign memory [%p] being crammed is "
+ "outside of expected range", (void *)newmem);
+ }
+ if (!zone->z_allows_foreign) {
+ panic("zone_cram_foreign: foreign memory [%p] being crammed in "
+ "zone '%s%s' not expecting it", (void *)newmem,
+ zone_heap_name(zone), zone_name(zone));
+ }
+ if (size % ptoa(zone->z_chunk_pages)) {
+ panic("zone_cram_foreign: foreign memory [%p] being crammed has "
+ "invalid size %zx", (void *)newmem, (size_t)size);
+ }
+ if (startup_phase >= STARTUP_SUB_ZALLOC) {
+ panic("zone_cram_foreign: foreign memory [%p] being crammed "
+ "after zalloc is initialized", (void *)newmem);
+ }
+
+ bzero((void *)newmem, size);
+ zcram(zone, newmem, pages, ZONE_ADDR_FOREIGN);
+}
+
+void
+zone_fill_initially(zone_t zone, vm_size_t nelems)
+{
+ kma_flags_t kmaflags;
+ kern_return_t kr;
+ vm_offset_t addr;
+ uint32_t pages;
+
+ assert(!zone->z_permanent && !zone->collectable && !zone->z_destructible);
+ assert(zone->z_elems_avail == 0);
+
+ kmaflags = zone_kma_flags(zone, Z_WAITOK) | KMA_PERMANENT;
+ pages = zone_alloc_pages_for_nelems(zone, nelems);
+ kr = kernel_memory_allocate(zone_submap(zone), &addr, ptoa(pages),
+ 0, kmaflags, VM_KERN_MEMORY_ZONE);
+ if (kr != KERN_SUCCESS) {
+ panic("kernel_memory_allocate() of %u pages failed", pages);
+ }
+
+ zone_meta_populate(addr, ptoa(pages));
+ zcram(zone, addr, pages, ZONE_ADDR_NATIVE);
+}
+
+static vm_offset_t
+zone_allocate_va(zone_t z, zalloc_flags_t flags)
+{
+ kma_flags_t kmaflags = zone_kma_flags(z, flags) | KMA_VAONLY;
+ vm_size_t size = ptoa(z->z_chunk_pages);
+ kern_return_t kr;
+ vm_offset_t addr;
+
+ kr = kernel_memory_allocate(zone_submap(z), &addr, size, 0,
+ kmaflags, VM_KERN_MEMORY_ZONE);
+
+#if !__LP64__
+ if (kr == KERN_NO_SPACE && z->z_replenishes) {
+ /*
+ * On 32bit the zone submaps do not have as much VA
+ * available, so use the VA reserved map for this
+ * purpose.
+ */
+ vm_map_t map = zone_submaps[Z_SUBMAP_IDX_VA_RESERVE];
+ kr = kernel_memory_allocate(map, &addr, size, 0,
+ kmaflags, VM_KERN_MEMORY_ZONE);
+ }
+#endif
+
+ if (kr == KERN_SUCCESS) {
+#if ZALLOC_EARLY_GAPS
+ if (__improbable(zone_caching_disabled < 0)) {
+ zone_allocate_random_early_gap(z);
+ }
+#endif /* ZALLOC_EARLY_GAPS */
+ zone_meta_populate(addr, size);
+ return addr;
+ }
+
+ panic_include_zprint = TRUE;
+#if CONFIG_ZLEAKS
+ if ((zleak_state & ZLEAK_STATE_ACTIVE)) {
+ panic_include_ztrace = TRUE;
+ }
+#endif /* CONFIG_ZLEAKS */
+ zone_t zone_largest = zone_find_largest();
+ panic("zalloc: zone map exhausted while allocating from zone [%s%s], "
+ "likely due to memory leak in zone [%s%s] "
+ "(%luM, %d elements allocated)",
+ zone_heap_name(z), zone_name(z),
+ zone_heap_name(zone_largest), zone_name(zone_largest),
+ (unsigned long)zone_size_wired(zone_largest) >> 20,
+ zone_count_allocated(zone_largest));
+}
+
+static bool
+zone_expand_pred_nope(__unused zone_t z)
+{
+ return false;
+}
+
+static inline void
+ZONE_TRACE_VM_KERN_REQUEST_START(vm_size_t size)
+{
+#if DEBUG || DEVELOPMENT
+ VM_DEBUG_CONSTANT_EVENT(vm_kern_request, VM_KERN_REQUEST, DBG_FUNC_START,
+ size, 0, 0, 0);
+#else
+ (void)size;
+#endif
+}
+
+static inline void
+ZONE_TRACE_VM_KERN_REQUEST_END(uint32_t pages)
+{
+#if DEBUG || DEVELOPMENT
+ task_t task = current_task();
+ if (pages && task) {
+ ledger_credit(task->ledger, task_ledgers.pages_grabbed_kern, pages);
+ }
+ VM_DEBUG_CONSTANT_EVENT(vm_kern_request, VM_KERN_REQUEST, DBG_FUNC_END,
+ pages, 0, 0, 0);
+#else
+ (void)pages;
+#endif
+}
+
+static void
+zone_expand_locked(zone_t z, zalloc_flags_t flags, bool (*pred)(zone_t))
+{
+ thread_t self = current_thread();
+ bool vm_priv = (self->options & TH_OPT_VMPRIV);
+ bool clear_vm_priv;
+
+ for (;;) {
+ if (!pred) {
+ /* NULL pred means "try just once" */
+ pred = zone_expand_pred_nope;
+ } else if (!pred(z)) {
+ return;
+ }
+
+ if (vm_priv && !z->z_expander_vm_priv) {
+ /*
+ * Claim the vm priv overcommit slot
+ *
+ * We do not track exact ownership for VM privileged
+ * threads, so use the rwlock boost as a stop-gap
+ * just in case.
+ */
+ set_thread_rwlock_boost();
+ z->z_expander_vm_priv = true;
+ clear_vm_priv = true;
+ } else {
+ clear_vm_priv = false;
+ }
+
+ if (z->z_expander == NULL) {
+ z->z_expander = self;
+ break;
+ }
+ if (clear_vm_priv) {
+ break;
+ }
+
+ if (flags & Z_NOPAGEWAIT) {
+ return;
+ }
+
+ z->z_expanding_wait = true;
+ lck_spin_sleep_with_inheritor(&z->z_lock, LCK_SLEEP_DEFAULT,
+ &z->z_expander, z->z_expander,
+ TH_UNINT, TIMEOUT_WAIT_FOREVER);
+ }
+
+ do {
+ struct zone_page_metadata *meta = NULL;
+ uint32_t new_va = 0, cur_pages = 0, min_pages = 0, pages = 0;
+ vm_page_t page_list = NULL;
+ vm_offset_t addr = 0;
+ int waited = 0;
+
+ /*
+ * While we hold the zone lock, look if there's VA we can:
+ * - complete from partial pages,
+ * - reuse from the sequester list.
+ *
+ * When the page is being populated we pretend we allocated
+ * an extra element so that zone_gc() can't attempt to free
+ * the chunk (as it could become empty while we wait for pages).
+ */
+ if (!zone_pva_is_null(z->z_pageq_va)) {
+ meta = zone_meta_queue_pop_native(z,
+ &z->z_pageq_va, &addr);
+ if (meta->zm_chunk_len == ZM_SECONDARY_PAGE) {
+ cur_pages = meta->zm_page_index;
+ meta -= cur_pages;
+ addr -= ptoa(cur_pages);
+ zone_meta_lock_in_partial(z, meta, cur_pages);
+ }
+ }
+ zone_unlock(z);
+
+ /*
+ * Do the zone leak activation here because zleak_activate()
+ * may block, and can't be done on the way out.
+ *
+ * Trigger jetsams via the vm_pageout_garbage_collect thread if
+ * we're running out of zone memory
+ */
+ zleak_activate_if_needed();
+ if (zone_map_nearing_exhaustion()) {
+ thread_wakeup((event_t)&vm_pageout_garbage_collect);
+ }
+
+ /*
+ * And now allocate pages to populate our VA.
+ */
+ if (z->z_percpu) {
+ min_pages = z->z_chunk_pages;
+ } else {
+ min_pages = (uint32_t)atop(round_page(zone_elem_size(z)));
+ }
+
+ ZONE_TRACE_VM_KERN_REQUEST_START(ptoa(z->z_chunk_pages - cur_pages));
+
+ while (pages < z->z_chunk_pages - cur_pages) {
+ vm_page_t m = vm_page_grab();
+
+ if (m) {
+ pages++;
+ m->vmp_snext = page_list;
+ page_list = m;
+ vm_page_zero_fill(m);
+ continue;
+ }
+
+ if (pages >= min_pages && (vm_pool_low() || waited)) {
+ break;
+ }
+
+ if ((flags & Z_NOPAGEWAIT) == 0) {
+ waited++;
+ VM_PAGE_WAIT();
+ continue;
+ }
+
+ /*
+ * Undo everything and bail out:
+ *
+ * - free pages
+ * - undo the fake allocation if any
+ * - put the VA back on the VA page queue.
+ */
+ vm_page_free_list(page_list, FALSE);
+ ZONE_TRACE_VM_KERN_REQUEST_END(pages);
+
+ zone_lock(z);
+
+ if (cur_pages) {
+ zone_meta_unlock_from_partial(z, meta, cur_pages);
+ }
+ if (meta) {
+ zone_meta_queue_push(z, &z->z_pageq_va,
+ meta + cur_pages);
+ }
+ goto page_shortage;
+ }
+
+ /*
+ * If we didn't find pre-allocated VA, then allocate a chunk
+ * of VA here.
+ */
+ if (addr == 0) {
+ addr = zone_allocate_va(z, flags);
+ meta = zone_meta_from_addr(addr);
+ new_va = z->z_chunk_pages;
+ }
+
+ kernel_memory_populate_with_pages(zone_submap(z),
+ addr + ptoa(cur_pages), ptoa(pages), page_list,
+ zone_kma_flags(z, flags), VM_KERN_MEMORY_ZONE);
+
+ ZONE_TRACE_VM_KERN_REQUEST_END(pages);
+
+ zcram_and_lock(z, addr, new_va, cur_pages, cur_pages + pages,
+ ZONE_ADDR_NATIVE);
+ } while (pred(z));
+
+page_shortage:
+ zleak_track_if_needed(z);
+
+ if (clear_vm_priv) {
+ z->z_expander_vm_priv = false;
+ clear_thread_rwlock_boost();
+ }
+ if (z->z_expander == self) {
+ z->z_expander = THREAD_NULL;
+ }
+ if (z->z_expanding_wait) {
+ z->z_expanding_wait = false;
+ wakeup_all_with_inheritor(&z->z_expander, THREAD_AWAKENED);
+ }
+}
+
+static bool
+zalloc_needs_refill(zone_t zone)
+{
+ if (zone->z_elems_free > zone->z_elems_rsv) {
+ return false;
+ }
+ if (zone->z_wired_cur < zone->z_wired_max) {
+ return true;
+ }
+ if (zone->exhaustible) {
+ return false;
+ }
+ if (zone->expandable) {
+ /*
+ * If we're expandable, just don't go through this again.
+ */
+ zone->z_wired_max = ~0u;
+ return true;
+ }
+ zone_unlock(zone);
+
+ panic_include_zprint = true;
+#if CONFIG_ZLEAKS
+ if (zleak_state & ZLEAK_STATE_ACTIVE) {
+ panic_include_ztrace = true;
+ }
+#endif /* CONFIG_ZLEAKS */
+ panic("zone '%s%s' exhausted", zone_heap_name(zone), zone_name(zone));
+}
+
+static void
+zone_expand_async(__unused thread_call_param_t p0, __unused thread_call_param_t p1)
+{
+ zone_foreach(z) {
+ if (z->no_callout) {
+ /* z_async_refilling will never be set */
+ continue;
+ }
+
+ if (z->z_replenishes) {
+ /* those use the zone_replenish_thread */
+ continue;
+ }
+
+ zone_lock(z);
+ if (z->z_self && z->z_async_refilling) {
+ z->z_async_refilling = false;
+ zone_expand_locked(z, Z_WAITOK, zalloc_needs_refill);
+ }
+ zone_unlock(z);
+ }
+}
+
+static inline void
+zone_expand_async_schedule_if_needed(zone_t zone)
+{
+ if (zone->z_elems_free > zone->z_elems_rsv || zone->z_async_refilling ||
+ zone->no_callout) {
+ return;
+ }
+
+ if (!zone->expandable && zone->z_wired_cur >= zone->z_wired_max) {
+ return;
+ }
+
+ if (zone->z_elems_free == 0 || !vm_pool_low()) {
+ zone->z_async_refilling = true;
+ thread_call_enter(&zone_expand_callout);
+ }
+}
+
+#endif /* !ZALLOC_TEST */
+#pragma mark zone replenishing (VM allocations)
+#if !ZALLOC_TEST
+
+/*
+ * Tracks how many zone_replenish threads are active, because zone_gc() wants
+ * for those to be finished before it proceeds.
+ *
+ * This counts how many replenish threads are active in
+ * ZONE_REPLENISH_ACTIVE_INC increments,
+ * and uses the low bit to track if there are any waiters.
+ */
+#define ZONE_REPLENISH_ACTIVE_NONE 0u
+#define ZONE_REPLENISH_ACTIVE_WAITER_BIT 1u
+#define ZONE_REPLENISH_ACTIVE_INC 2u
+#define ZONE_REPLENISH_ACTIVE_MASK (~ZONE_REPLENISH_ACTIVE_WAITER_BIT)
+static unsigned _Atomic zone_replenish_active;
+static unsigned zone_replenish_wakeups;
+static unsigned zone_replenish_wakeups_initiated;
+static unsigned zone_replenish_throttle_count;
+
+#define ZONE_REPLENISH_TARGET (16 * 1024)
+
+static void
+zone_replenish_wait_if_needed(void)
+{
+ /*
+ * This check can be racy, the reserves ought to be enough
+ * to compensate for a little race
+ */
+ while (os_atomic_load(&zone_replenish_active, relaxed) !=
+ ZONE_REPLENISH_ACTIVE_NONE) {
+ unsigned o_active, n_active;
+
+ assert_wait(&zone_replenish_active, THREAD_UNINT);
+
+ os_atomic_rmw_loop(&zone_replenish_active, o_active, n_active, relaxed, {
+ if (o_active == ZONE_REPLENISH_ACTIVE_NONE) {
+ os_atomic_rmw_loop_give_up({
+ clear_wait(current_thread(), THREAD_AWAKENED);
+ return;
+ });
+ }
+ if (o_active & ZONE_REPLENISH_ACTIVE_WAITER_BIT) {
+ os_atomic_rmw_loop_give_up(break);
+ }
+ n_active = o_active | ZONE_REPLENISH_ACTIVE_WAITER_BIT;
+ });
+ thread_block(THREAD_CONTINUE_NULL);
+ }
+}
+
+__attribute__((noinline))
+static void
+zone_replenish_locked(zone_t zone)
+{
+ thread_t thr = current_thread();
+ uint32_t min_free;
+
+ zone_replenish_wakeups++;
+
+ /*
+ * We'll let threads continue to allocate under the reserve:
+ * - until it depleted to 50% for regular threads,
+ * - until it depleted to 25% for VM_PRIV threads.
+ *
+ * After that only TH_OPT_ZONE_PRIV threads may continue.
+ */
+ if (thr->options & TH_OPT_VMPRIV) {
+ min_free = zone->z_elems_rsv / 4;
+ } else {
+ min_free = zone->z_elems_rsv / 2;
+ }
+
+ while (zone->z_elems_free <= zone->z_elems_rsv) {
+ /*
+ * Wakeup the replenish thread if not running.
+ */
+ if (!zone->z_async_refilling) {
+ os_atomic_add(&zone_replenish_active,
+ ZONE_REPLENISH_ACTIVE_INC, relaxed);
+ zone->z_async_refilling = true;
+ zone_replenish_wakeups_initiated++;
+ thread_wakeup(&zone->z_elems_rsv);
+ }
+
+ if (zone->z_elems_free > min_free) {
+ break;
+ }
+
+ /*
+ * TH_OPT_ZONE_PRIV threads are the GC thread and a replenish
+ * thread itself.
+ *
+ * Replenish threads *need* to use the reserve. GC threads need
+ * to get through the current allocation, but then will wait at
+ * a higher level after they've dropped any locks which would
+ * deadlock the replenish thread.
+ *
+ * The value of (refill_level / 2) in the previous bit of code
+ * should have given us headroom even though this thread didn't
+ * wait.
+ */
+ if (thr->options & TH_OPT_ZONE_PRIV) {
+ assert(zone->z_elems_free != 0);
+ break;
+ }
+
+ if (startup_phase < STARTUP_SUB_MACH_IPC) {
+ panic("vm_map_steal_memory didn't steal enough memory: "
+ "trying to grow [%s%s] before the scheduler has started",
+ zone_heap_name(zone), zone_name(zone));
+ }
+
+ /*
+ * Wait for the replenish threads to add more elements
+ * for us to allocate from.
+ */
+ zone_replenish_throttle_count++;
+ zone->z_replenish_wait = true;
+ assert_wait_timeout(zone, THREAD_UNINT, 1, NSEC_PER_MSEC);
+ zone_unlock(zone);
+ thread_block(THREAD_CONTINUE_NULL);
+ zone_lock(zone);
+ zone->z_replenish_wait = false;
+
+ assert(zone->z_self == zone);
+ }
+}
+
+static bool
+zone_replenish_needed(zone_t z)
+{
+ return z->z_elems_free <= z->z_elems_rsv;
+}
+
+/*
+ * High priority VM privileged thread used to asynchronously refill a given zone.
+ * These are needed for data structures used by the lower level VM itself. The
+ * replenish thread maintains a reserve of elements, so that the VM will never
+ * block in the zone allocator.
+ */
+__dead2
+static void
+zone_replenish_thread(void *_z, wait_result_t __unused wr)
+{
+ unsigned o_active, n_active;
+ zone_t z = _z;
+
+ zone_lock(z);
+ assert(z->z_self == z);
+ assert(z->z_async_refilling && z->z_replenishes);
+
+ zone_expand_locked(z, Z_WAITOK, zone_replenish_needed);
+
+ if (z->z_replenish_wait) {
+ /* Wakeup any potentially throttled allocations */
+ z->z_replenish_wait = false;
+ thread_wakeup(z);
+ }
+
+ /* wakeup zone_reclaim() callers that were possibly waiting */
+ os_atomic_rmw_loop(&zone_replenish_active, o_active, n_active, relaxed, {
+ if (os_sub_overflow(o_active, ZONE_REPLENISH_ACTIVE_INC, &n_active)) {
+ panic("zone_replenish_active corrupt: %d", o_active);
+ }
+ if ((n_active & ZONE_REPLENISH_ACTIVE_MASK) == 0) {
+ n_active = ZONE_REPLENISH_ACTIVE_NONE;
+ }
+ });
+
+ if (n_active == ZONE_REPLENISH_ACTIVE_NONE &&
+ (o_active & ZONE_REPLENISH_ACTIVE_WAITER_BIT)) {
+ thread_wakeup(&zone_replenish_active);
+ }
+
+ z->z_async_refilling = false;
+ assert_wait(&z->z_elems_rsv, THREAD_UNINT);
+
+ zone_unlock(z);
+
+ thread_block_parameter(zone_replenish_thread, z);
+ __builtin_unreachable();
+}
+
+void
+zone_replenish_configure(zone_t z)
+{
+ thread_t th;
+ kern_return_t kr;
+ char name[MAXTHREADNAMESIZE];
+
+ zone_lock(z);
+ assert(!z->z_replenishes && !z->z_destructible);
+ z->z_elems_rsv = (uint16_t)(ZONE_REPLENISH_TARGET / zone_elem_size(z));
+ z->z_replenishes = true;
+ os_atomic_add(&zone_replenish_active, ZONE_REPLENISH_ACTIVE_INC, relaxed);
+ z->z_async_refilling = true;
+ zone_unlock(z);
+
+ kr = kernel_thread_create(zone_replenish_thread, z, MAXPRI_KERNEL, &th);
+ if (kr != KERN_SUCCESS) {
+ panic("zone_replenish_configure, thread create: 0x%x", kr);
+ }
+ /* make sure this thread can't lose its stack */
+ assert(th->reserved_stack == th->kernel_stack);
+
+ snprintf(name, sizeof(name), "z_replenish(%s)", zone_name(z));
+ thread_set_thread_name(th, name);
+
+ thread_mtx_lock(th);
+ th->options |= TH_OPT_VMPRIV | TH_OPT_ZONE_PRIV;
+ thread_start(th);
+ thread_mtx_unlock(th);
+
+ thread_deallocate(th);
+}
+
+/*! @} */
+#endif /* !ZALLOC_TEST */
+#pragma mark zone jetsam integration
+#if !ZALLOC_TEST
+
+/*
+ * We're being very conservative here and picking a value of 95%. We might need to lower this if
+ * we find that we're not catching the problem and are still hitting zone map exhaustion panics.
+ */
+#define ZONE_MAP_JETSAM_LIMIT_DEFAULT 95
+
+/*
+ * Trigger zone-map-exhaustion jetsams if the zone map is X% full, where X=zone_map_jetsam_limit.
+ * Can be set via boot-arg "zone_map_jetsam_limit". Set to 95% by default.
+ */
+TUNABLE_WRITEABLE(unsigned int, zone_map_jetsam_limit, "zone_map_jetsam_limit",
+ ZONE_MAP_JETSAM_LIMIT_DEFAULT);
+
+void
+get_zone_map_size(uint64_t *current_size, uint64_t *capacity)
+{
+ vm_offset_t phys_pages = os_atomic_load(&zones_phys_page_mapped_count, relaxed);
+ *current_size = ptoa_64(phys_pages);
+ *capacity = ptoa_64(zone_phys_mapped_max_pages);
+}
+
+void
+get_largest_zone_info(char *zone_name, size_t zone_name_len, uint64_t *zone_size)
+{
+ zone_t largest_zone = zone_find_largest();
+
+ /*
+ * Append kalloc heap name to zone name (if zone is used by kalloc)
+ */
+ snprintf(zone_name, zone_name_len, "%s%s",
+ zone_heap_name(largest_zone), largest_zone->z_name);
+
+ *zone_size = zone_size_wired(largest_zone);
+}
+
+bool
+zone_map_nearing_exhaustion(void)
+{
+ uint64_t phys_pages = os_atomic_load(&zones_phys_page_mapped_count, relaxed);
+ return phys_pages * 100 > zone_phys_mapped_max_pages * zone_map_jetsam_limit;
+}
+
+
+#define VMENTRY_TO_VMOBJECT_COMPARISON_RATIO 98
+
+/*
+ * Tries to kill a single process if it can attribute one to the largest zone. If not, wakes up the memorystatus thread
+ * to walk through the jetsam priority bands and kill processes.
+ */
+static void
+kill_process_in_largest_zone(void)
+{
+ pid_t pid = -1;
+ zone_t largest_zone = zone_find_largest();
+
+ printf("zone_map_exhaustion: Zone mapped %lld of %lld, used %lld, capacity %lld [jetsam limit %d%%]\n",
+ ptoa_64(os_atomic_load(&zones_phys_page_mapped_count, relaxed)),
+ ptoa_64(zone_phys_mapped_max_pages),
+ (uint64_t)zone_submaps_approx_size(),
+ (uint64_t)(zone_foreign_size() + zone_native_size()),
+ zone_map_jetsam_limit);
+ printf("zone_map_exhaustion: Largest zone %s%s, size %lu\n", zone_heap_name(largest_zone),
+ largest_zone->z_name, (uintptr_t)zone_size_wired(largest_zone));
+
+ /*
+ * We want to make sure we don't call this function from userspace.
+ * Or we could end up trying to synchronously kill the process
+ * whose context we're in, causing the system to hang.
+ */
+ assert(current_task() == kernel_task);
+
+ /*
+ * If vm_object_zone is the largest, check to see if the number of
+ * elements in vm_map_entry_zone is comparable.
+ *
+ * If so, consider vm_map_entry_zone as the largest. This lets us target
+ * a specific process to jetsam to quickly recover from the zone map
+ * bloat.
+ */
+ if (largest_zone == vm_object_zone) {
+ unsigned int vm_object_zone_count = zone_count_allocated(vm_object_zone);
+ unsigned int vm_map_entry_zone_count = zone_count_allocated(vm_map_entry_zone);
+ /* Is the VM map entries zone count >= 98% of the VM objects zone count? */
+ if (vm_map_entry_zone_count >= ((vm_object_zone_count * VMENTRY_TO_VMOBJECT_COMPARISON_RATIO) / 100)) {
+ largest_zone = vm_map_entry_zone;
+ printf("zone_map_exhaustion: Picking VM map entries as the zone to target, size %lu\n",
+ (uintptr_t)zone_size_wired(largest_zone));
+ }
+ }
+
+ /* TODO: Extend this to check for the largest process in other zones as well. */
+ if (largest_zone == vm_map_entry_zone) {
+ pid = find_largest_process_vm_map_entries();
+ } else {
+ printf("zone_map_exhaustion: Nothing to do for the largest zone [%s%s]. "
+ "Waking up memorystatus thread.\n", zone_heap_name(largest_zone),
+ largest_zone->z_name);
+ }
+ if (!memorystatus_kill_on_zone_map_exhaustion(pid)) {
+ printf("zone_map_exhaustion: Call to memorystatus failed, victim pid: %d\n", pid);
+ }
+}
+
+#endif /* !ZALLOC_TEST */
+#pragma mark zfree
+#if !ZALLOC_TEST
+#if KASAN_ZALLOC
+
+/*!
+ * @defgroup zfree
+ * @{
+ *
+ * @brief
+ * The codepath for zone frees.
+ *
+ * @discussion
+ * There are 4 major ways to allocate memory that end up in the zone allocator:
+ * - @c zfree()
+ * - @c zfree_percpu()
+ * - @c kfree*()
+ * - @c zfree_permanent()
+ *
+ * While permanent zones have their own allocation scheme, all other codepaths
+ * will eventually go through the @c zfree_ext() choking point.
+ *
+ * Ignoring the @c gzalloc_free() codepath, the decision tree looks like this:
+ * <code>
+ * zfree_ext()
+ * ├───> zfree_cached() ────────────────╮
+ * │ │ │
+ * │ │ │
+ * │ ├───> zfree_cached_slow() ───┤
+ * │ │ │ │
+ * │ │ v │
+ * ╰───────┴───> zfree_item() ──────────┴───>
+ * </code>
+ *
+ * @c zfree_ext() takes care of all the generic work to perform on an element
+ * before it is freed (zeroing, logging, tagging, ...) then will hand it off to:
+ * - @c zfree_item() if zone caching is off
+ * - @c zfree_cached() if zone caching is on.
+ *
+ * @c zfree_cached can take a number of decisions:
+ * - a fast path if the (f) or (a) magazines have space (preemption disabled),
+ * - using the cpu local or recirculation depot calling @c zfree_cached_slow(),
+ * - falling back to @c zfree_item() when CPU caching has been disabled.
+ */
+
+/*
+ * Called from zfree() to add the element being freed to the KASan quarantine.
+ *
+ * Returns true if the newly-freed element made it into the quarantine without
+ * displacing another, false otherwise. In the latter case, addrp points to the
+ * address of the displaced element, which will be freed by the zone.
+ */
+static bool
+kasan_quarantine_freed_element(
+ zone_t *zonep, /* the zone the element is being freed to */
+ void **addrp) /* address of the element being freed */
+{
+ zone_t zone = *zonep;
+ void *addr = *addrp;
+
+ /*
+ * Resize back to the real allocation size and hand off to the KASan
+ * quarantine. `addr` may then point to a different allocation, if the
+ * current element replaced another in the quarantine. The zone then
+ * takes ownership of the swapped out free element.
+ */
+ vm_size_t usersz = zone_elem_size(zone) - 2 * zone->z_kasan_redzone;
+ vm_size_t sz = usersz;
+
+ if (addr && zone->z_kasan_redzone) {
+ kasan_check_free((vm_address_t)addr, usersz, KASAN_HEAP_ZALLOC);
+ addr = (void *)kasan_dealloc((vm_address_t)addr, &sz);
+ assert(sz == zone_elem_size(zone));
+ }
+ if (addr && !zone->kasan_noquarantine) {
+ kasan_free(&addr, &sz, KASAN_HEAP_ZALLOC, zonep, usersz, true);
+ if (!addr) {
+ return TRUE;
+ }
+ }
+ if (addr && zone->kasan_noquarantine) {
+ kasan_unpoison(addr, zone_elem_size(zone));
+ }
+ *addrp = addr;
+ return FALSE;
+}
+
+#endif /* KASAN_ZALLOC */
+
+__header_always_inline void
+zfree_drop(zone_t zone, struct zone_page_metadata *meta, zone_element_t ze,
+ bool recirc)
+{
+ vm_offset_t esize = zone_elem_size(zone);
+
+ if (zone_meta_mark_free(meta, ze) == recirc) {
+ zone_meta_double_free_panic(zone, ze, __func__);
+ }
+
+ vm_offset_t old_size = meta->zm_alloc_size;
+ vm_offset_t max_size = ptoa(meta->zm_chunk_len) + ZM_ALLOC_SIZE_LOCK;
+ vm_offset_t new_size = zone_meta_alloc_size_sub(zone, meta, esize);
+
+ if (new_size == 0) {
+ /* whether the page was on the intermediate or all_used, queue, move it to free */
+ zone_meta_requeue(zone, &zone->z_pageq_empty, meta);
+ zone->z_wired_empty += meta->zm_chunk_len;
+ } else if (old_size + esize > max_size) {
+ /* first free element on page, move from all_used */
+ zone_meta_requeue(zone, &zone->z_pageq_partial, meta);
+ }
+}
+
+static void
+zfree_item(zone_t zone, struct zone_page_metadata *meta, zone_element_t ze)
+{
+ /* transfer preemption count to lock */
+ zone_lock_nopreempt_check_contention(zone, NULL);
+
+ zfree_drop(zone, meta, ze, false);
+ zone_elems_free_add(zone, 1);
+
+ zone_unlock(zone);
+}
+
+__attribute__((noinline))
+static void
+zfree_cached_slow(zone_t zone, struct zone_page_metadata *meta,
+ zone_element_t ze, zone_cache_t cache)
+{
+ struct zone_depot mags = STAILQ_HEAD_INITIALIZER(mags);
+ zone_magazine_t mag = NULL;
+ uint16_t n = 0;
+
+ if (zone_meta_is_free(meta, ze)) {
+ zone_meta_double_free_panic(zone, ze, __func__);
+ }
+
+ if (zone == zc_magazine_zone) {
+ mag = (zone_magazine_t)zone_element_addr(ze,
+ zone_elem_size(zone));
+#if KASAN_ZALLOC
+ kasan_poison_range((vm_offset_t)mag, zone_elem_size(zone),
+ ASAN_VALID);
+#endif
+ } else {
+ mag = zone_magazine_alloc(Z_NOWAIT);
+ if (__improbable(mag == NULL)) {
+ return zfree_item(zone, meta, ze);
+ }
+ mag->zm_cur = 1;
+ mag->zm_elems[0] = ze;
+ }
+
+ mag = zone_magazine_replace(&cache->zc_free_cur,
+ &cache->zc_free_elems, mag);
+
+ z_debug_assert(cache->zc_free_cur <= 1);
+ z_debug_assert(mag->zm_cur == zc_mag_size());
+
+ STAILQ_INSERT_HEAD(&mags, mag, zm_link);
+ n = 1;
+
+ if (cache->zc_depot_max >= 2 * zc_mag_size()) {
+ /*
+ * If we can use the local depot (zc_depot_max allows for
+ * 2 magazines worth of elements) then:
+ *
+ * 1. if we have space for an extra depot locally,
+ * push it, and leave.
+ *
+ * 2. if we overflow, then take (1 / zc_recirc_denom)
+ * of the depot out, in order to migrate it to the
+ * recirculation depot.
+ */
+ zone_depot_lock_nopreempt(cache);
+
+ if ((cache->zc_depot_cur + 2) * zc_mag_size() <=
+ cache->zc_depot_max) {
+ cache->zc_depot_cur++;
+ STAILQ_INSERT_TAIL(&cache->zc_depot, mag, zm_link);
+ return zone_depot_unlock(cache);
+ }
+
+ while (zc_recirc_denom * cache->zc_depot_cur * zc_mag_size() >=
+ (zc_recirc_denom - 1) * cache->zc_depot_max) {
+ mag = STAILQ_FIRST(&cache->zc_depot);
+ STAILQ_REMOVE_HEAD(&cache->zc_depot, zm_link);
+ STAILQ_INSERT_TAIL(&mags, mag, zm_link);
+ cache->zc_depot_cur--;
+ n++;
+ }
+
+ zone_depot_unlock(cache);
+ } else {
+ enable_preemption();
+ }
+
+ /*
+ * Preflight validity of all the elements before we touch the zone
+ * metadata, and then insert them into the recirculation depot.
+ */
+ STAILQ_FOREACH(mag, &mags, zm_link) {
+ for (uint16_t i = 0; i < zc_mag_size(); i++) {
+ zone_element_validate(zone, mag->zm_elems[i]);
+ }
+ }
+
+ zone_lock_check_contention(zone, cache);
+
+ STAILQ_FOREACH(mag, &mags, zm_link) {
+ for (uint16_t i = 0; i < zc_mag_size(); i++) {
+ zone_element_t e = mag->zm_elems[i];
+
+ if (!zone_meta_mark_free(zone_meta_from_element(e), e)) {
+ zone_meta_double_free_panic(zone, e, __func__);
+ }
+ }
+ }
+ STAILQ_CONCAT(&zone->z_recirc, &mags);
+ zone->z_recirc_cur += n;
+
+ zone_elems_free_add(zone, n * zc_mag_size());
+
+ zone_unlock(zone);
+}
+
+static void
+zfree_cached(zone_t zone, struct zone_page_metadata *meta, zone_element_t ze)
+{
+ zone_cache_t cache = zpercpu_get(zone->z_pcpu_cache);
+
+ if (cache->zc_free_cur >= zc_mag_size()) {
+ if (cache->zc_alloc_cur >= zc_mag_size()) {
+ return zfree_cached_slow(zone, meta, ze, cache);
+ }
+ zone_cache_swap_magazines(cache);
+ }
+
+ if (__improbable(cache->zc_alloc_elems == NULL)) {
+ return zfree_item(zone, meta, ze);
+ }
+
+ if (zone_meta_is_free(meta, ze)) {
+ zone_meta_double_free_panic(zone, ze, __func__);
+ }
+
+ uint16_t idx = cache->zc_free_cur++;
+ if (idx >= zc_mag_size()) {
+ zone_accounting_panic(zone, "zc_free_cur overflow");
+ }
+ cache->zc_free_elems[idx] = ze;
+
+ enable_preemption();
+}
+
+/*
+ * The function is noinline when zlog can be used so that the backtracing can
+ * reliably skip the zfree_ext() and zfree_log_trace()
+ * boring frames.
+ */
+#if ZONE_ENABLE_LOGGING
+__attribute__((noinline))
+#endif /* ZONE_ENABLE_LOGGING */
+void
+zfree_ext(zone_t zone, zone_stats_t zstats, void *addr)
+{
+ struct zone_page_metadata *page_meta;
+ vm_offset_t elem = (vm_offset_t)addr;
+ vm_size_t elem_size = zone_elem_size(zone);
+ zone_element_t ze;
+
+ DTRACE_VM2(zfree, zone_t, zone, void*, addr);
+ TRACE_MACHLEAKS(ZFREE_CODE, ZFREE_CODE_2, elem_size, elem);
+#if VM_MAX_TAG_ZONES
+ if (__improbable(zone->tags)) {
+ vm_tag_t tag = *ztSlot(zone, elem) >> 1;
+ // set the tag with b0 clear so the block remains inuse
+ *ztSlot(zone, elem) = 0xFFFE;
+ vm_tag_update_zone_size(tag, zone->tag_zone_index,
+ -(long)elem_size);
+ }
+#endif /* VM_MAX_TAG_ZONES */
+
+#if KASAN_ZALLOC
+ if (kasan_quarantine_freed_element(&zone, &addr)) {
+ return;
+ }
+ /*
+ * kasan_quarantine_freed_element() might return a different
+ * {zone, addr} than the one being freed for kalloc heaps.
+ *
+ * Make sure we reload everything.
+ */
+ elem = (vm_offset_t)addr;
+ elem_size = zone_elem_size(zone);
+#endif
+#if CONFIG_ZLEAKS
+ /*
+ * Zone leak detection: un-track the allocation
+ */
+ if (__improbable(zone->zleak_on)) {
+ zleak_free(elem, elem_size);
+ }
+#endif /* CONFIG_ZLEAKS */
+#if ZONE_ENABLE_LOGGING
+ if (__improbable(DO_LOGGING(zone))) {
+ zfree_log_trace(zone, elem, __builtin_frame_address(0));
+ }
+#endif /* ZONE_ENABLE_LOGGING */
+#if CONFIG_GZALLOC
+ if (__improbable(zone->gzalloc_tracked)) {
+ return gzalloc_free(zone, zstats, addr);
+ }
+#endif /* CONFIG_GZALLOC */
+
+ page_meta = zone_element_resolve(zone, elem, elem_size, &ze);
+ ze.ze_value |= zfree_clear_or_poison(zone, elem, elem_size);
+#if KASAN_ZALLOC
+ if (zone->z_percpu) {
+ zpercpu_foreach_cpu(i) {
+ kasan_poison_range(elem + ptoa(i), elem_size,
+ ASAN_HEAP_FREED);
+ }
+ } else {
+ kasan_poison_range(elem, elem_size, ASAN_HEAP_FREED);
+ }
+#endif
+
+ disable_preemption();
+ zpercpu_get(zstats)->zs_mem_freed += elem_size;
+
+ if (zone->z_pcpu_cache) {
+ return zfree_cached(zone, page_meta, ze);
+ }
+
+ return zfree_item(zone, page_meta, ze);
+}
+
+void
+(zfree)(union zone_or_view zov, void *addr)
+{
+ zone_t zone = zov.zov_view->zv_zone;
+ zone_stats_t zstats = zov.zov_view->zv_stats;
+ assert(!zone->z_percpu);
+ zfree_ext(zone, zstats, addr);
+}
+
+void
+zfree_percpu(union zone_or_view zov, void *addr)
+{
+ zone_t zone = zov.zov_view->zv_zone;
+ zone_stats_t zstats = zov.zov_view->zv_stats;
+ assert(zone->z_percpu);
+ zfree_ext(zone, zstats, (void *)__zpcpu_demangle(addr));
+}
+
+/*! @} */
+#endif /* !ZALLOC_TEST */
+#pragma mark zalloc
+#if !ZALLOC_TEST
+
+/*!
+ * @defgroup zalloc
+ * @{
+ *
+ * @brief
+ * The codepath for zone allocations.
+ *
+ * @discussion
+ * There are 4 major ways to allocate memory that end up in the zone allocator:
+ * - @c zalloc(), @c zalloc_flags(), ...
+ * - @c zalloc_percpu()
+ * - @c kalloc*()
+ * - @c zalloc_permanent()
+ *
+ * While permanent zones have their own allocation scheme, all other codepaths
+ * will eventually go through the @c zalloc_ext() choking point.
+ *
+ * Ignoring the @c zalloc_gz() codepath, the decision tree looks like this:
+ * <code>
+ * zalloc_ext()
+ * │
+ * ├───> zalloc_cached() ──────> zalloc_cached_fast() ───╮
+ * │ │ ^ │
+ * │ │ │ │
+ * │ ╰───> zalloc_cached_slow() ───╯ │
+ * │ │ │
+ * │<─────────────────╮ ├─────────────╮ │
+ * │ │ │ │ │
+ * │ │ v │ │
+ * │<───────╮ ╭──> zalloc_item_slow() ────┤ │
+ * │ │ │ │ │
+ * │ │ │ v │
+ * ╰───> zalloc_item() ──────────> zalloc_item_fast() ───┤
+ * │
+ * v
+ * zalloc_return()
+ * </code>
+ *
+ *
+ * The @c zalloc_item() track is used when zone caching is off:
+ * - @c zalloc_item_fast() is used when there are enough elements available,
+ * - @c zalloc_item_slow() is used when a refill is needed, which can cause
+ * the zone to grow. This is the only codepath that refills.
+ *
+ * This track uses the zone lock for serialization:
+ * - taken in @c zalloc_item(),
+ * - maintained during @c zalloc_item_slow() (possibly dropped and re-taken),
+ * - dropped in @c zalloc_item_fast().
+ *
+ *
+ * The @c zalloc_cached() track is used when zone caching is on:
+ * - @c zalloc_cached_fast() is taken when the cache has elements,
+ * - @c zalloc_cached_slow() is taken if a cache refill is needed.
+ * It can chose many strategies:
+ * ~ @c zalloc_cached_from_depot() to try to reuse cpu stashed magazines,
+ * ~ using the global recirculation depot @c z_recirc,
+ * ~ using zalloc_import() if the zone has enough elements,
+ * ~ falling back to the @c zalloc_item() track if zone caching is disabled
+ * due to VM pressure or the zone has no available elements.
+ *
+ * This track disables preemption for serialization:
+ * - preemption is disabled in @c zalloc_cached(),
+ * - kept disabled during @c zalloc_cached_slow(), converted into a zone lock
+ * if switching to @c zalloc_item_slow(),
+ * - preemption is reenabled in @c zalloc_cached_fast().
+ *
+ * @c zalloc_cached_from_depot() also takes depot locks (taken by the caller,
+ * released by @c zalloc_cached_from_depot().
+ *
+ * In general the @c zalloc_*_slow() codepaths deal with refilling and will
+ * tail call into the @c zalloc_*_fast() code to perform the actual allocation.
+ *
+ * @c zalloc_return() is the final function everyone tail calls into,
+ * which prepares the element for consumption by the caller and deals with
+ * common treatment (zone logging, tags, kasan, validation, ...).
+ */
+
+/*!
+ * @function zalloc_import
+ *
+ * @brief
+ * Import @c n elements in the specified array, opposite of @c zfree_drop().
+ *
+ * @param zone The zone to import elements from
+ * @param elems The array to import into
+ * @param n The number of elements to import. Must be non zero,
+ * and smaller than @c zone->z_elems_free.
+ */
+__header_always_inline void
+zalloc_import(zone_t zone, zone_element_t *elems, uint32_t n)
+{
+ vm_size_t esize = zone_elem_size(zone);
+ uint32_t i = 0;
+
+ assertf(STAILQ_EMPTY(&zone->z_recirc),
+ "Trying to import from zone %p [%s%s] with non empty recirc",
+ zone, zone_heap_name(zone), zone_name(zone));
+
+ do {
+ vm_offset_t page, eidx, size = 0;
+ struct zone_page_metadata *meta;
+
+ if (!zone_pva_is_null(zone->z_pageq_partial)) {
+ meta = zone_pva_to_meta(zone->z_pageq_partial);
+ page = zone_pva_to_addr(zone->z_pageq_partial);
+ } else if (!zone_pva_is_null(zone->z_pageq_empty)) {
+ meta = zone_pva_to_meta(zone->z_pageq_empty);
+ page = zone_pva_to_addr(zone->z_pageq_empty);
+ zone_counter_sub(zone, z_wired_empty, meta->zm_chunk_len);
+ } else {
+ zone_accounting_panic(zone, "z_elems_free corruption");
+ }
+
+ if (!zone_has_index(zone, meta->zm_index)) {
+ zone_page_metadata_index_confusion_panic(zone, page, meta);
+ }
+
+ vm_offset_t old_size = meta->zm_alloc_size;
+ vm_offset_t max_size = ptoa(meta->zm_chunk_len) + ZM_ALLOC_SIZE_LOCK;
+
+ do {
+ eidx = zone_meta_find_and_clear_bit(zone, meta);
+ elems[i++] = zone_element_encode(page, eidx, ZPM_AUTO);
+ size += esize;
+ } while (i < n && old_size + size + esize <= max_size);
+
+ vm_offset_t new_size = zone_meta_alloc_size_add(zone, meta, size);
+
+ if (new_size + esize > max_size) {
+ zone_meta_requeue(zone, &zone->z_pageq_full, meta);
+ } else if (old_size == 0) {
+ /* remove from free, move to intermediate */
+ zone_meta_requeue(zone, &zone->z_pageq_partial, meta);
+ }
+ } while (i < n);
+}
+
+/*!
+ * @function zalloc_return
+ *
+ * @brief
+ * Performs the tail-end of the work required on allocations before the caller
+ * uses them.
+ *
+ * @discussion
+ * This function is called without any zone lock held,
+ * and preemption back to the state it had when @c zalloc_ext() was called.
+ *
+ * @param zone The zone we're allocating from.
+ * @param ze The encoded element we just allocated.
+ * @param flags The flags passed to @c zalloc_ext() (for Z_ZERO).
+ * @param elem_size The element size for this zone.
+ * @param freemag An optional magazine that needs to be freed.
+ */
+__attribute__((noinline))
+static void *
+zalloc_return(zone_t zone, zone_element_t ze, zalloc_flags_t flags,
+ vm_offset_t elem_size, zone_magazine_t freemag)
+{
+ vm_offset_t addr = zone_element_addr(ze, elem_size);
+
+#if KASAN_ZALLOC
+ if (zone->z_percpu) {
+ zpercpu_foreach_cpu(i) {
+ kasan_poison_range(addr + ptoa(i), elem_size,
+ ASAN_VALID);
+ }
+ } else {
+ kasan_poison_range(addr, elem_size, ASAN_VALID);
+ }
+#endif
+#if ZALLOC_ENABLE_POISONING
+ zalloc_validate_element(zone, addr, elem_size, zone_element_prot(ze));
+#endif /* ZALLOC_ENABLE_POISONING */
+#if ZONE_ENABLE_LOGGING || CONFIG_ZLEAKS
+ if (__improbable(zalloc_should_log_or_trace_leaks(zone, elem_size))) {
+ zalloc_log_or_trace_leaks(zone, addr, __builtin_frame_address(0));
+ }
+#endif /* ZONE_ENABLE_LOGGING || CONFIG_ZLEAKS */
+#if KASAN_ZALLOC
+ if (zone->z_kasan_redzone) {
+ addr = kasan_alloc(addr, elem_size,
+ elem_size - 2 * zone->z_kasan_redzone,
+ zone->z_kasan_redzone);
+ elem_size -= 2 * zone->z_kasan_redzone;
+ }
+ /*
+ * Initialize buffer with unique pattern only if memory
+ * wasn't expected to be zeroed.
+ */
+ if (!zone->z_free_zeroes && !(flags & Z_ZERO)) {
+ kasan_leak_init(addr, elem_size);
+ }
+#endif /* KASAN_ZALLOC */
+ if ((flags & Z_ZERO) && !zone->z_free_zeroes) {
+ bzero((void *)addr, elem_size);
+ }
+
+#if VM_MAX_TAG_ZONES
+ if (__improbable(zone->tags)) {
+ vm_tag_t tag = zalloc_flags_get_tag(flags);
+ if (tag == VM_KERN_MEMORY_NONE) {
+ tag = VM_KERN_MEMORY_KALLOC;
+ }
+ // set the tag with b0 clear so the block remains inuse
+ *ztSlot(zone, addr) = (vm_tag_t)(tag << 1);
+ vm_tag_update_zone_size(tag, zone->tag_zone_index,
+ (long)elem_size);
+ }
+#endif /* VM_MAX_TAG_ZONES */
+
+ TRACE_MACHLEAKS(ZALLOC_CODE, ZALLOC_CODE_2, elem_size, addr);
+ DTRACE_VM2(zalloc, zone_t, zone, void*, addr);
+ if (freemag) {
+ zone_magazine_free(freemag);
+ }
+ return (void *)addr;
+}
+
+#if CONFIG_GZALLOC
+/*!
+ * @function zalloc_gz
+ *
+ * @brief
+ * Performs allocations for zones using gzalloc.
+ *
+ * @discussion
+ * This function is noinline so that it doesn't affect the codegen
+ * of the fastpath.
+ */
+__attribute__((noinline))
+static void *
+zalloc_gz(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags)
+{
+ vm_offset_t addr = gzalloc_alloc(zone, zstats, flags);
+ return zalloc_return(zone, zone_element_encode(addr, 0, ZPM_AUTO),
+ flags, zone_elem_size(zone), NULL);
+}
+#endif /* CONFIG_GZALLOC */
+
+static void *
+zalloc_item_fast(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags)
+{
+ vm_size_t esize = zone_elem_size(zone);
+ zone_element_t ze;
+
+ zalloc_import(zone, &ze, 1);
+ zone_elems_free_sub(zone, 1);
+ zpercpu_get(zstats)->zs_mem_allocated += esize;
+ zone_unlock(zone);
+
+ return zalloc_return(zone, ze, flags, esize, NULL);
+}
+
+/*!
+ * @function zalloc_item_slow
+ *
+ * @brief
+ * Performs allocations when the zone is out of elements.
+ *
+ * @discussion
+ * This function might drop the lock and reenable preemption,
+ * which means the per-CPU caching layer or recirculation depot
+ * might have received elements.
+ */
+__attribute__((noinline))
+static void *
+zalloc_item_slow(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags)
+{
+ if (zone->z_replenishes) {
+ zone_replenish_locked(zone);
+ } else {
+ if ((flags & Z_NOWAIT) == 0) {
+ zone_expand_locked(zone, flags, zalloc_needs_refill);
+ }
+ if (flags & (Z_NOWAIT | Z_NOPAGEWAIT)) {
+ zone_expand_async_schedule_if_needed(zone);
+ }
+ if (__improbable(zone->z_elems_free == 0)) {
+ zone_unlock(zone);
+ if (__improbable(flags & Z_NOFAIL)) {
+ zone_nofail_panic(zone);
+ }
+ DTRACE_VM2(zalloc, zone_t, zone, void*, NULL);
+ return NULL;
+ }
+ }
+
+ /*
+ * We might have changed core or got preempted/blocked while expanding
+ * the zone. Allocating from the zone when the recirculation depot
+ * is not empty is not allowed.
+ *
+ * It will be rare but possible for the depot to refill while we were
+ * waiting for pages. If that happens we need to start over.
+ */
+ if (!STAILQ_EMPTY(&zone->z_recirc)) {
+ zone_unlock(zone);
+ return zalloc_ext(zone, zstats, flags);
+ }
+
+ return zalloc_item_fast(zone, zstats, flags);
+}
+
+/*!
+ * @function zalloc_item
+ *
+ * @brief
+ * Performs allocations when zone caching is off.
+ *
+ * @discussion
+ * This function calls @c zalloc_item_slow() when refilling the zone
+ * is needed, or @c zalloc_item_fast() if the zone has enough free elements.
+ */
+static void *
+zalloc_item(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags)
+{
+ zone_lock_check_contention(zone, NULL);
+
+ /*
+ * When we commited to the zalloc_item() path,
+ * zone caching might have been flipped/enabled.
+ *
+ * If we got preempted for long enough, the recirculation layer
+ * can have been populated, and allocating from the zone would be
+ * incorrect.
+ *
+ * So double check for this extremely rare race here.
+ */
+ if (__improbable(!STAILQ_EMPTY(&zone->z_recirc))) {
+ zone_unlock(zone);
+ return zalloc_ext(zone, zstats, flags);
+ }
+
+ if (__improbable(zone->z_elems_free <= zone->z_elems_rsv)) {
+ return zalloc_item_slow(zone, zstats, flags);
+ }
+
+ return zalloc_item_fast(zone, zstats, flags);
+}
+
+static void *
+zalloc_cached_fast(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags,
+ zone_cache_t cache, zone_magazine_t freemag)
+{
+ vm_offset_t esize = zone_elem_size(zone);
+ zone_element_t ze;
+ uint32_t index;
+
+ index = --cache->zc_alloc_cur;
+ if (index >= zc_mag_size()) {
+ zone_accounting_panic(zone, "zc_alloc_cur wrap around");
+ }
+ ze = cache->zc_alloc_elems[index];
+ cache->zc_alloc_elems[index].ze_value = 0;
+
+ zpercpu_get(zstats)->zs_mem_allocated += esize;
+ enable_preemption();
+
+ if (zone_meta_is_free(zone_meta_from_element(ze), ze)) {
+ zone_meta_double_free_panic(zone, ze, __func__);
+ }
+
+ return zalloc_return(zone, ze, flags, esize, freemag);
+}
+
+static void *
+zalloc_cached_from_depot(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags,
+ zone_cache_t cache, zone_cache_t depot, zone_magazine_t mag)
+{
+ STAILQ_REMOVE_HEAD(&depot->zc_depot, zm_link);
+ if (depot->zc_depot_cur-- == 0) {
+ zone_accounting_panic(zone, "zc_depot_cur wrap-around");
+ }
+ zone_depot_unlock_nopreempt(depot);
+
+ mag = zone_magazine_replace(&cache->zc_alloc_cur,
+ &cache->zc_alloc_elems, mag);
+
+ z_debug_assert(cache->zc_alloc_cur == zc_mag_size());
+ z_debug_assert(mag->zm_cur == 0);
+
+ if (zone == zc_magazine_zone) {
+ enable_preemption();
+ bzero(mag, zone_elem_size(zone));
+ return mag;
+ }
+
+ return zalloc_cached_fast(zone, zstats, flags, cache, mag);
+}
+
+__attribute__((noinline))
+static void *
+zalloc_cached_slow(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags,
+ zone_cache_t cache)
+{
+ zone_magazine_t mag = NULL;
+ struct zone_depot mags = STAILQ_HEAD_INITIALIZER(mags);
+
+ /*
+ * Try to allocate from our local depot, if there's one.
+ */
+ if (STAILQ_FIRST(&cache->zc_depot)) {
+ zone_depot_lock_nopreempt(cache);
+
+ if ((mag = STAILQ_FIRST(&cache->zc_depot)) != NULL) {
+ return zalloc_cached_from_depot(zone, zstats, flags,
+ cache, cache, mag);
+ }
+
+ zone_depot_unlock_nopreempt(cache);
+ }
+
+ zone_lock_nopreempt_check_contention(zone, cache);
+
+ /*
+ * If the recirculation depot is empty, we'll need to import.
+ * The system is tuned for this to be extremely rare.
+ */
+ if (__improbable(STAILQ_EMPTY(&zone->z_recirc))) {
+ uint16_t n_elems = zc_mag_size();
+
+ if (zone->z_elems_free < n_elems + zone->z_elems_rsv / 2 &&
+ os_sub_overflow(zone->z_elems_free,
+ zone->z_elems_rsv / 2, &n_elems)) {
+ n_elems = 0;
+ }
+
+ z_debug_assert(n_elems <= zc_mag_size());
+
+ if (__improbable(n_elems == 0)) {
+ /*
+ * If importing elements would deplete the zone,
+ * call zalloc_item_slow()
+ */
+ return zalloc_item_slow(zone, zstats, flags);
+ }
+
+ if (__improbable(zone_caching_disabled)) {
+ if (__improbable(zone_caching_disabled < 0)) {
+ /*
+ * In the first 10s after boot, mess with
+ * the scan position in order to make early
+ * allocations patterns less predictible.
+ */
+ zone_early_scramble_rr(zone, zstats);
+ }
+ return zalloc_item_fast(zone, zstats, flags);
+ }
+
+ zalloc_import(zone, cache->zc_alloc_elems, n_elems);
+
+ cache->zc_alloc_cur = n_elems;
+ zone_elems_free_sub(zone, n_elems);
+
+ zone_unlock_nopreempt(zone);
+
+ return zalloc_cached_fast(zone, zstats, flags, cache, NULL);
+ }
+
+ uint16_t n_mags = 0;
+
+ /*
+ * If the recirculation depot has elements, then try to fill
+ * the local per-cpu depot to (1 / zc_recirc_denom)
+ */
+ do {
+ mag = STAILQ_FIRST(&zone->z_recirc);
+ STAILQ_REMOVE_HEAD(&zone->z_recirc, zm_link);
+ STAILQ_INSERT_TAIL(&mags, mag, zm_link);
+ n_mags++;
+
+ for (uint16_t i = 0; i < zc_mag_size(); i++) {
+ zone_element_t e = mag->zm_elems[i];
+
+ if (!zone_meta_mark_used(zone_meta_from_element(e), e)) {
+ zone_meta_double_free_panic(zone, e, __func__);
+ }
+ }
+ } while (!STAILQ_EMPTY(&zone->z_recirc) &&
+ zc_recirc_denom * n_mags * zc_mag_size() <= cache->zc_depot_max);
+
+ zone_elems_free_sub(zone, n_mags * zc_mag_size());
+ zone_counter_sub(zone, z_recirc_cur, n_mags);
+
+ zone_unlock_nopreempt(zone);
+
+ /*
+ * And then incorporate everything into our per-cpu layer.
+ */
+ mag = STAILQ_FIRST(&mags);
+ STAILQ_REMOVE_HEAD(&mags, zm_link);
+ mag = zone_magazine_replace(&cache->zc_alloc_cur,
+ &cache->zc_alloc_elems, mag);
+ z_debug_assert(cache->zc_alloc_cur == zc_mag_size());
+ z_debug_assert(mag->zm_cur == 0);
+
+ if (--n_mags > 0) {
+ zone_depot_lock_nopreempt(cache);
+ cache->zc_depot_cur += n_mags;
+ STAILQ_CONCAT(&cache->zc_depot, &mags);
+ zone_depot_unlock_nopreempt(cache);
+ }
+
+ return zalloc_cached_fast(zone, zstats, flags, cache, mag);
+}
+
+/*!
+ * @function zalloc_cached
+ *
+ * @brief
+ * Performs allocations when zone caching is on.
+ *
+ * @discussion
+ * This function calls @c zalloc_cached_fast() when the caches have elements
+ * ready.
+ *
+ * Else it will call @c zalloc_cached_slow() so that the cache is refilled,
+ * which might switch to the @c zalloc_item_slow() track when the backing zone
+ * needs to be refilled.
+ */
+static void *
+zalloc_cached(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags)
+{
+ zone_cache_t cache;
+
+ disable_preemption();
+ cache = zpercpu_get(zone->z_pcpu_cache);
+
+ if (cache->zc_alloc_cur == 0) {
+ if (__improbable(cache->zc_free_cur == 0)) {
+ return zalloc_cached_slow(zone, zstats, flags, cache);
+ }
+ zone_cache_swap_magazines(cache);
+ }
+
+ return zalloc_cached_fast(zone, zstats, flags, cache, NULL);
+}
+
+/*!
+ * @function zalloc_ext
+ *
+ * @brief
+ * The core implementation of @c zalloc(), @c zalloc_flags(), @c zalloc_percpu().
+ */
+void *
+zalloc_ext(zone_t zone, zone_stats_t zstats, zalloc_flags_t flags)
+{
+ /*
+ * KASan uses zalloc() for fakestack, which can be called anywhere.
+ * However, we make sure these calls can never block.
+ */
+ assert(zone->kasan_fakestacks ||
+ ml_get_interrupts_enabled() ||
+ ml_is_quiescing() ||
+ debug_mode_active() ||
+ startup_phase < STARTUP_SUB_EARLY_BOOT);
+
+ /*
+ * Make sure Z_NOFAIL was not obviously misused
+ */
+ if (zone->z_replenishes) {
+ assert((flags & (Z_NOWAIT | Z_NOPAGEWAIT)) == 0);
+ } else if (flags & Z_NOFAIL) {
+ assert(!zone->exhaustible &&
+ (flags & (Z_NOWAIT | Z_NOPAGEWAIT)) == 0);
+ }
+
+#if CONFIG_GZALLOC
+ if (__improbable(zone->gzalloc_tracked)) {
+ return zalloc_gz(zone, zstats, flags);
+ }
+#endif /* CONFIG_GZALLOC */
+
+ if (zone->z_pcpu_cache) {
+ return zalloc_cached(zone, zstats, flags);
+ }
+
+ return zalloc_item(zone, zstats, flags);
+}
+
+void *
+zalloc(union zone_or_view zov)
+{
+ return zalloc_flags(zov, Z_WAITOK);
+}
+
+void *
+zalloc_noblock(union zone_or_view zov)
+{
+ return zalloc_flags(zov, Z_NOWAIT);
+}
+
+void *
+zalloc_flags(union zone_or_view zov, zalloc_flags_t flags)
+{
+ zone_t zone = zov.zov_view->zv_zone;
+ zone_stats_t zstats = zov.zov_view->zv_stats;
+ assert(!zone->z_percpu);
+ return zalloc_ext(zone, zstats, flags);
+}
+
+void *
+zalloc_percpu(union zone_or_view zov, zalloc_flags_t flags)
+{
+ zone_t zone = zov.zov_view->zv_zone;
+ zone_stats_t zstats = zov.zov_view->zv_stats;
+ assert(zone->z_percpu);
+ return (void *)__zpcpu_mangle(zalloc_ext(zone, zstats, flags));
+}
+
+static void *
+_zalloc_permanent(zone_t zone, vm_size_t size, vm_offset_t mask)
+{
+ struct zone_page_metadata *page_meta;
+ vm_offset_t offs, addr;
+ zone_pva_t pva;
+
+ assert(ml_get_interrupts_enabled() ||
+ ml_is_quiescing() ||
+ debug_mode_active() ||
+ startup_phase < STARTUP_SUB_EARLY_BOOT);
+
+ size = (size + mask) & ~mask;
+ assert(size <= PAGE_SIZE);
+
+ zone_lock(zone);
+ assert(zone->z_self == zone);
+
+ for (;;) {
+ pva = zone->z_pageq_partial;
+ while (!zone_pva_is_null(pva)) {
+ page_meta = zone_pva_to_meta(pva);
+ if (page_meta->zm_bump + size <= PAGE_SIZE) {
+ goto found;
+ }
+ pva = page_meta->zm_page_next;
+ }
+
+ zone_expand_locked(zone, Z_WAITOK, NULL);
+ }
+
+found:
+ offs = (uint16_t)((page_meta->zm_bump + mask) & ~mask);
+ page_meta->zm_bump = (uint16_t)(offs + size);
+ page_meta->zm_alloc_size += size;
+ zone->z_elems_free -= size;
+ zpercpu_get(zone->z_stats)->zs_mem_allocated += size;
+
+ if (page_meta->zm_alloc_size >= PAGE_SIZE - sizeof(vm_offset_t)) {
+ zone_meta_requeue(zone, &zone->z_pageq_full, page_meta);
+ }
+
+ zone_unlock(zone);
+
+ addr = offs + zone_pva_to_addr(pva);
+
+ DTRACE_VM2(zalloc, zone_t, zone, void*, addr);
+ return (void *)addr;
+}
+
+static void *
+_zalloc_permanent_large(size_t size, vm_offset_t mask)
+{
+ kern_return_t kr;
+ vm_offset_t addr;
+
+ kr = kernel_memory_allocate(kernel_map, &addr, size, mask,
+ KMA_KOBJECT | KMA_PERMANENT | KMA_ZERO,
+ VM_KERN_MEMORY_KALLOC);
+ if (kr != 0) {
+ panic("zalloc_permanent: unable to allocate %zd bytes (%d)",
+ size, kr);
+ }
+ return (void *)addr;
+}
+
+void *
+zalloc_permanent(vm_size_t size, vm_offset_t mask)
+{
+ if (size <= PAGE_SIZE) {
+ zone_t zone = &zone_array[ZONE_ID_PERMANENT];
+ return _zalloc_permanent(zone, size, mask);
+ }
+ return _zalloc_permanent_large(size, mask);
+}
+
+void *
+zalloc_percpu_permanent(vm_size_t size, vm_offset_t mask)
+{
+ zone_t zone = &zone_array[ZONE_ID_PERCPU_PERMANENT];
+ return (void *)__zpcpu_mangle(_zalloc_permanent(zone, size, mask));
+}
+
+/*! @} */
+#endif /* !ZALLOC_TEST */
+#pragma mark zone GC / trimming
+#if !ZALLOC_TEST
+
+static thread_call_data_t zone_defrag_callout;
+
+static void
+zone_reclaim_chunk(zone_t z, struct zone_page_metadata *meta, uint32_t free_count)
+{
+ vm_address_t page_addr;
+ vm_size_t size_to_free;
+ uint32_t bitmap_ref;
+ uint32_t page_count;
+ bool sequester = z->z_va_sequester && !z->z_destroyed;
+
+ zone_meta_queue_pop_native(z, &z->z_pageq_empty, &page_addr);
+
+ page_count = meta->zm_chunk_len;
+
+ if (meta->zm_alloc_size) {
+ zone_metadata_corruption(z, meta, "alloc_size");
+ }
+ if (z->z_percpu) {
+ if (page_count != 1) {
+ zone_metadata_corruption(z, meta, "page_count");
+ }
+ size_to_free = ptoa(z->z_chunk_pages);
+ os_atomic_sub(&zones_phys_page_mapped_count,
+ z->z_chunk_pages, relaxed);
+ } else {
+ if (page_count > z->z_chunk_pages) {
+ zone_metadata_corruption(z, meta, "page_count");
+ }
+ if (page_count < z->z_chunk_pages) {
+ /* Dequeue non populated VA from z_pageq_va */
+ zone_meta_remqueue(z, meta + page_count);
+ }
+ size_to_free = ptoa(page_count);
+ os_atomic_sub(&zones_phys_page_mapped_count, page_count, relaxed);
+ }
+
+ zone_counter_sub(z, z_elems_free, free_count);
+ zone_counter_sub(z, z_elems_avail, free_count);
+ zone_counter_sub(z, z_wired_empty, page_count);
+ zone_counter_sub(z, z_wired_cur, page_count);
+ if (z->z_elems_free_min < free_count) {
+ z->z_elems_free_min = 0;
+ } else {
+ z->z_elems_free_min -= free_count;
+ }
+ if (z->z_elems_free_max < free_count) {
+ z->z_elems_free_max = 0;
+ } else {
+ z->z_elems_free_max -= free_count;
+ }
+
+ bitmap_ref = 0;
+ if (sequester) {
+ if (meta->zm_inline_bitmap) {
+ for (int i = 0; i < meta->zm_chunk_len; i++) {
+ meta[i].zm_bitmap = 0;
+ }
+ } else {
+ bitmap_ref = meta->zm_bitmap;
+ meta->zm_bitmap = 0;
+ }
+ meta->zm_chunk_len = 0;
+ } else {
+ if (!meta->zm_inline_bitmap) {
+ bitmap_ref = meta->zm_bitmap;
+ }
+ zone_counter_sub(z, z_va_cur, z->z_percpu ? 1 : z->z_chunk_pages);
+ bzero(meta, sizeof(*meta) * z->z_chunk_pages);
+ }
+
+ zone_unlock(z);
+
+ if (bitmap_ref) {
+ zone_bits_free(bitmap_ref);
+ }
+
+ /* Free the pages for metadata and account for them */
+#if KASAN_ZALLOC
+ kasan_poison_range(page_addr, size_to_free, ASAN_VALID);
+#endif
+#if VM_MAX_TAG_ZONES
+ if (z->tags) {
+ ztMemoryRemove(z, page_addr, size_to_free);
+ }
+#endif /* VM_MAX_TAG_ZONES */
+
+ if (sequester) {
+ kernel_memory_depopulate(zone_submap(z), page_addr,
+ size_to_free, KMA_KOBJECT, VM_KERN_MEMORY_ZONE);
+ } else {
+ kmem_free(zone_submap(z), page_addr, ptoa(z->z_chunk_pages));
+ }
+
+ /*
+ * Freeing memory sometimes needs some (for example vm map entries
+ * to represent holes).
+ *
+ * If there are any active replenish threads, we need to let them work
+ * while we hold no locks. Only do so right after we just freed memory
+ * once however to give them even more chances to find fresh pages.
+ */
+ zone_replenish_wait_if_needed();
+
+ thread_yield_to_preemption();
+
+ zone_lock(z);
+
+ if (sequester) {
+ zone_meta_queue_push(z, &z->z_pageq_va, meta);
+ }
+}
+
+static uint16_t
+zone_reclaim_elements(zone_t z, uint16_t *count, zone_element_t *elems)
+{
+ uint16_t n = *count;
+
+ z_debug_assert(n <= zc_mag_size());
+
+ for (uint16_t i = 0; i < n; i++) {
+ zone_element_t ze = elems[i];
+ elems[i].ze_value = 0;
+ zfree_drop(z, zone_element_validate(z, ze), ze, false);
+ }
+
+ *count = 0;
+ return n;
+}
+
+static uint16_t
+zone_reclaim_recirc_magazine(zone_t z, struct zone_depot *mags)
+{
+ zone_magazine_t mag = STAILQ_FIRST(&z->z_recirc);
+
+ STAILQ_REMOVE_HEAD(&z->z_recirc, zm_link);
+ STAILQ_INSERT_TAIL(mags, mag, zm_link);
+ zone_counter_sub(z, z_recirc_cur, 1);
+
+ z_debug_assert(mag->zm_cur == zc_mag_size());
+
+ for (uint16_t i = 0; i < zc_mag_size(); i++) {
+ zone_element_t ze = mag->zm_elems[i];
+ mag->zm_elems[i].ze_value = 0;
+ zfree_drop(z, zone_element_validate(z, ze), ze, true);
+ }
+
+ mag->zm_cur = 0;
+
+ return zc_mag_size();
+}
+
+static void
+zone_depot_trim(zone_cache_t zc, struct zone_depot *head)
+{
+ zone_magazine_t mag;
+
+ if (zc->zc_depot_cur == 0 ||
+ 2 * (zc->zc_depot_cur + 1) * zc_mag_size() <= zc->zc_depot_max) {
+ return;
+ }
+
+ zone_depot_lock(zc);
+
+ while (zc->zc_depot_cur &&
+ 2 * (zc->zc_depot_cur + 1) * zc_mag_size() > zc->zc_depot_max) {
+ mag = STAILQ_FIRST(&zc->zc_depot);
+ STAILQ_REMOVE_HEAD(&zc->zc_depot, zm_link);
+ STAILQ_INSERT_TAIL(head, mag, zm_link);
+ zc->zc_depot_cur--;
+ }
+
+ zone_depot_unlock(zc);
+}
+
+__enum_decl(zone_reclaim_mode_t, uint32_t, {
+ ZONE_RECLAIM_TRIM,
+ ZONE_RECLAIM_DRAIN,
+ ZONE_RECLAIM_DESTROY,
+});
+
+/*!
+ * @function zone_reclaim
+ *
+ * @brief
+ * Drains or trim the zone.
+ *
+ * @discussion
+ * Draining the zone will free it from all its elements.
+ *
+ * Trimming the zone tries to respect the working set size, and avoids draining
+ * the depot when it's not necessary.
+ *
+ * @param z The zone to reclaim from
+ * @param mode The purpose of this reclaim.
+ */
+static void
+zone_reclaim(zone_t z, zone_reclaim_mode_t mode)
+{
+ struct zone_depot mags = STAILQ_HEAD_INITIALIZER(mags);
+ zone_magazine_t mag, tmp;
+
+ zone_lock(z);
+
+ if (mode == ZONE_RECLAIM_DESTROY) {
+ if (!z->z_destructible || z->z_pcpu_cache ||
+ z->z_elems_rsv || z->z_allows_foreign) {
+ panic("zdestroy: Zone %s%s isn't destructible",
+ zone_heap_name(z), z->z_name);
+ }
+
+ if (!z->z_self || z->z_expander || z->z_expander_vm_priv ||
+ z->z_async_refilling || z->z_expanding_wait) {
+ panic("zdestroy: Zone %s%s in an invalid state for destruction",
+ zone_heap_name(z), z->z_name);
+ }
+
+#if !KASAN_ZALLOC
+ /*
+ * Unset the valid bit. We'll hit an assert failure on further
+ * operations on this zone, until zinit() is called again.
+ *
+ * Leave the zone valid for KASan as we will see zfree's on
+ * quarantined free elements even after the zone is destroyed.
+ */
+ z->z_self = NULL;
+#endif
+ z->z_destroyed = true;
+ } else if (z->z_destroyed) {
+ return zone_unlock(z);
+ } else if (z->z_replenishes && z->z_async_refilling) {
+ /*
+ * If the zone is replenishing, leave it alone.
+ */
+ return zone_unlock(z);
+ }
+
+ if (z->z_pcpu_cache) {
+ if (mode != ZONE_RECLAIM_TRIM) {
+ zpercpu_foreach(zc, z->z_pcpu_cache) {
+ zc->zc_depot_max /= 2;
+ }
+ } else {
+ zpercpu_foreach(zc, z->z_pcpu_cache) {
+ if (zc->zc_depot_max > 0) {
+ zc->zc_depot_max--;
+ }
+ }
+ }
+
+ zone_unlock(z);
+
+ if (mode == ZONE_RECLAIM_TRIM) {
+ zpercpu_foreach(zc, z->z_pcpu_cache) {
+ zone_depot_trim(zc, &mags);
+ }
+ } else {
+ zpercpu_foreach(zc, z->z_pcpu_cache) {
+ zone_depot_lock(zc);
+ STAILQ_CONCAT(&mags, &zc->zc_depot);
+ zc->zc_depot_cur = 0;
+ zone_depot_unlock(zc);
+ }
+ }
+
+ zone_lock(z);
+
+ uint32_t freed = 0;
+
+ STAILQ_FOREACH(mag, &mags, zm_link) {
+ freed += zone_reclaim_elements(z,
+ &mag->zm_cur, mag->zm_elems);
+
+ if (freed >= zc_free_batch_size) {
+ z->z_elems_free_min += freed;
+ z->z_elems_free_max += freed;
+ z->z_elems_free += freed;
+ zone_unlock(z);
+ thread_yield_to_preemption();
+ zone_lock(z);
+ freed = 0;
+ }
+ }
+
+ if (mode == ZONE_RECLAIM_DESTROY) {
+ zpercpu_foreach(zc, z->z_pcpu_cache) {
+ freed += zone_reclaim_elements(z,
+ &zc->zc_alloc_cur, zc->zc_alloc_elems);
+ freed += zone_reclaim_elements(z,
+ &zc->zc_free_cur, zc->zc_free_elems);
+ }
+
+ z->z_elems_free_wss = 0;
+ z->z_elems_free_min = 0;
+ z->z_elems_free_max = 0;
+ z->z_contention_cur = 0;
+ z->z_contention_wma = 0;
+ } else {
+ z->z_elems_free_min += freed;
+ z->z_elems_free_max += freed;
+ }
+ z->z_elems_free += freed;
+ }
+
+ for (;;) {
+ struct zone_page_metadata *meta;
+ uint32_t count, goal, freed = 0;
+
+ goal = z->z_elems_rsv;
+ if (mode == ZONE_RECLAIM_TRIM) {
+ /*
+ * When trimming, only free elements in excess
+ * of the working set estimate.
+ *
+ * However if we are in a situation where the working
+ * set estimate is clearly growing, ignore the estimate
+ * as the next working set update will grow it and
+ * we want to avoid churn.
+ */
+ goal = MAX(goal, MAX(z->z_elems_free_wss,
+ z->z_elems_free - z->z_elems_free_min));
+
+ /*
+ * Add some slop to account for "the last partial chunk in flight"
+ * so that we do not deplete the recirculation depot too harshly.
+ */
+ goal += z->z_chunk_elems / 2;
+ }
+
+ if (z->z_elems_free <= goal) {
+ break;
+ }
+
+ /*
+ * If we're above target, but we have no free page, then drain
+ * the recirculation depot until we get a free chunk or exhaust
+ * the depot.
+ *
+ * This is rather abrupt but also somehow will reduce
+ * fragmentation anyway, and the zone code will import
+ * over time anyway.
+ */
+ while (z->z_recirc_cur) {
+ if (z->z_recirc_cur * zc_mag_size() <= goal &&
+ !zone_pva_is_null(z->z_pageq_empty)) {
+ break;
+ }
+ if (freed >= zc_free_batch_size) {
+ zone_unlock(z);
+ thread_yield_to_preemption();
+ zone_lock(z);
+ freed = 0;
+ /* we dropped the lock, needs to reassess */
+ continue;
+ }
+ freed += zone_reclaim_recirc_magazine(z, &mags);
+ }
+
+ if (zone_pva_is_null(z->z_pageq_empty)) {
+ break;
+ }
+
+ meta = zone_pva_to_meta(z->z_pageq_empty);
+ count = (uint32_t)ptoa(meta->zm_chunk_len) / zone_elem_size(z);
+
+ if (z->z_elems_free - count < goal) {
+ break;
+ }
+
+ zone_reclaim_chunk(z, meta, count);
+ }
+
+ zone_unlock(z);
+
+ STAILQ_FOREACH_SAFE(mag, &mags, zm_link, tmp) {
+ zone_magazine_free(mag);
+ }
+}
+
+static void
+zone_reclam_all(zone_reclaim_mode_t mode)
+{
+ /*
+ * Start with zones with VA sequester since depopulating
+ * pages will not need to allocate vm map entries for holes,
+ * which will give memory back to the system faster.
+ */
+ zone_foreach(z) {
+ if (z == zc_magazine_zone) {
+ continue;
+ }
+ if (z->z_va_sequester && z->collectable) {
+ zone_reclaim(z, mode);
+ }
+ }
+
+ zone_foreach(z) {
+ if (z == zc_magazine_zone) {
+ continue;
+ }
+ if (!z->z_va_sequester && z->collectable) {
+ zone_reclaim(z, mode);
+ }
+ }
+
+ zone_reclaim(zc_magazine_zone, mode);
+}
+
+void
+zone_gc(zone_gc_level_t level)
+{
+ zone_reclaim_mode_t mode;
+
+ switch (level) {
+ case ZONE_GC_TRIM:
+ mode = ZONE_RECLAIM_TRIM;
+ break;
+ case ZONE_GC_DRAIN:
+ mode = ZONE_RECLAIM_DRAIN;
+ break;
+ case ZONE_GC_JETSAM:
+ kill_process_in_largest_zone();
+ mode = ZONE_RECLAIM_TRIM;
+ break;
+ }
+
+ current_thread()->options |= TH_OPT_ZONE_PRIV;
+ lck_mtx_lock(&zone_gc_lock);
+
+ zone_reclam_all(mode);
+
+ if (level == ZONE_GC_JETSAM && zone_map_nearing_exhaustion()) {
+ /*
+ * If we possibly killed a process, but we're still critical,
+ * we need to drain harder.
+ */
+ zone_reclam_all(ZONE_RECLAIM_DRAIN);
+ }
+
+ lck_mtx_unlock(&zone_gc_lock);
+ current_thread()->options &= ~TH_OPT_ZONE_PRIV;
+}
+
+void
+zone_gc_trim(void)
+{
+ zone_gc(ZONE_GC_TRIM);
+}
+
+void
+zone_gc_drain(void)
+{
+ zone_gc(ZONE_GC_DRAIN);
+}
+
+static bool
+zone_defrag_needed(zone_t z)
+{
+ uint32_t recirc_size = z->z_recirc_cur * zc_mag_size();
+
+ if (recirc_size <= z->z_chunk_elems / 2) {
+ return false;
+ }
+ return recirc_size * zc_defrag_ratio > z->z_elems_free_wss * 100;
+}
+
+/*!
+ * @function zone_defrag_async
+ *
+ * @brief
+ * Resize the recirculation depot to match the working set size.
+ *
+ * @discussion
+ * When zones grow very large due to a spike in usage, and then some of those
+ * elements get freed, the elements in magazines in the recirculation depot
+ * are in no particular order.
+ *
+ * In order to control fragmentation, we need to detect "empty" pages so that
+ * they get onto the @c z_pageq_empty freelist, so that allocations re-pack
+ * naturally.
+ *
+ * This is done very gently, never in excess of the working set and some slop.
+ */
+static void
+zone_defrag_async(__unused thread_call_param_t p0, __unused thread_call_param_t p1)
+{
+ zone_foreach(z) {
+ struct zone_depot mags = STAILQ_HEAD_INITIALIZER(mags);
+ zone_magazine_t mag, tmp;
+ uint32_t freed = 0, goal = 0;
+
+ if (!z->collectable || !zone_defrag_needed(z)) {
+ continue;
+ }
+
+ zone_lock(z);
+
+ goal = z->z_elems_free_wss + z->z_chunk_elems / 2 +
+ zc_mag_size() - 1;
+
+ while (z->z_recirc_cur * zc_mag_size() > goal) {
+ if (freed >= zc_free_batch_size) {
+ zone_unlock(z);
+ thread_yield_to_preemption();
+ zone_lock(z);
+ freed = 0;
+ /* we dropped the lock, needs to reassess */
+ continue;
+ }
+ freed += zone_reclaim_recirc_magazine(z, &mags);
+ }
+
+ zone_unlock(z);
+
+ STAILQ_FOREACH_SAFE(mag, &mags, zm_link, tmp) {
+ zone_magazine_free(mag);
+ }
+ }
+}
+
+void
+compute_zone_working_set_size(__unused void *param)
+{
+ uint32_t zc_auto = zc_auto_threshold;
+ bool kick_defrag = false;
+
+ /*
+ * Keep zone caching disabled until the first proc is made.
+ */
+ if (__improbable(zone_caching_disabled < 0)) {
+ return;
+ }
+
+ zone_caching_disabled = vm_pool_low();
+#if ZALLOC_EARLY_GAPS
+ zone_cleanup_early_gaps_if_needed();
+#endif
+
+ if (os_mul_overflow(zc_auto, Z_CONTENTION_WMA_UNIT, &zc_auto)) {
+ zc_auto = 0;
+ }
+
+ zone_foreach(z) {
+ uint32_t wma;
+ bool needs_caching = false;
+
+ if (z->z_self != z) {
+ continue;
+ }
+
+ zone_lock(z);
+
+ wma = z->z_elems_free_max - z->z_elems_free_min;
+ wma = (3 * wma + z->z_elems_free_wss) / 4;
+ z->z_elems_free_max = z->z_elems_free_min = z->z_elems_free;
+ z->z_elems_free_wss = wma;
+
+ if (!kick_defrag && zone_defrag_needed(z)) {
+ kick_defrag = true;
+ }
+
+ /* fixed point decimal of contentions per second */
+ wma = z->z_contention_cur * Z_CONTENTION_WMA_UNIT /
+ ZONE_WSS_UPDATE_PERIOD;
+ z->z_contention_cur = 0;
+ z->z_contention_wma = (3 * wma + z->z_contention_wma) / 4;
+
+ /*
+ * If the zone seems to be very quiet,
+ * gently lower its cpu-local depot size.
+ */
+ if (z->z_pcpu_cache && wma < Z_CONTENTION_WMA_UNIT / 2 &&
+ z->z_contention_wma < Z_CONTENTION_WMA_UNIT / 2) {
+ zpercpu_foreach(zc, z->z_pcpu_cache) {
+ if (zc->zc_depot_max > zc_mag_size()) {
+ zc->zc_depot_max--;
+ }
+ }
+ }
+
+ /*
+ * If the zone has been contending like crazy for two periods,
+ * and is eligible, maybe it's time to enable caching.
+ */
+ if (!z->z_nocaching && !z->z_pcpu_cache && !z->exhaustible &&
+ zc_auto && z->z_contention_wma >= zc_auto && wma >= zc_auto) {
+ needs_caching = true;
+ }
+
+ zone_unlock(z);
+
+ if (needs_caching) {
+ zone_enable_caching(z);
+ }
+ }
+
+ if (kick_defrag) {
+ thread_call_enter(&zone_defrag_callout);
+ }
+}
+
+#endif /* !ZALLOC_TEST */
+#pragma mark vm integration, MIG routines
+#if !ZALLOC_TEST
+
+/*
+ * Creates a vm_map_copy_t to return to the caller of mach_* MIG calls
+ * requesting zone information.
+ * Frees unused pages towards the end of the region, and zero'es out unused
+ * space on the last page.
+ */
+static vm_map_copy_t
+create_vm_map_copy(
+ vm_offset_t start_addr,
+ vm_size_t total_size,
+ vm_size_t used_size)
+{
+ kern_return_t kr;
+ vm_offset_t end_addr;
+ vm_size_t free_size;
+ vm_map_copy_t copy;
+
+ if (used_size != total_size) {
+ end_addr = start_addr + used_size;
+ free_size = total_size - (round_page(end_addr) - start_addr);
+
+ if (free_size >= PAGE_SIZE) {
+ kmem_free(ipc_kernel_map,
+ round_page(end_addr), free_size);
+ }
+ bzero((char *) end_addr, round_page(end_addr) - end_addr);
+ }
+
+ kr = vm_map_copyin(ipc_kernel_map, (vm_map_address_t)start_addr,
+ (vm_map_size_t)used_size, TRUE, ©);
+ assert(kr == KERN_SUCCESS);
+
+ return copy;
+}
+
+static boolean_t
+get_zone_info(
+ zone_t z,
+ mach_zone_name_t *zn,
+ mach_zone_info_t *zi)
+{
+ struct zone zcopy;
+ vm_size_t cached = 0;
+
+ assert(z != ZONE_NULL);
+ zone_lock(z);
+ if (!z->z_self) {
+ zone_unlock(z);
+ return FALSE;
+ }
+ zcopy = *z;
+ if (z->z_pcpu_cache) {
+ zpercpu_foreach(zc, z->z_pcpu_cache) {
+ cached += zc->zc_alloc_cur + zc->zc_free_cur;
+ cached += zc->zc_depot_cur * zc_mag_size();
+ }
+ }
+ zone_unlock(z);
+
+ if (zn != NULL) {
+ /*
+ * Append kalloc heap name to zone name (if zone is used by kalloc)
+ */
+ char temp_zone_name[MAX_ZONE_NAME] = "";
+ snprintf(temp_zone_name, MAX_ZONE_NAME, "%s%s",
+ zone_heap_name(z), z->z_name);
+
+ /* assuming here the name data is static */
+ (void) __nosan_strlcpy(zn->mzn_name, temp_zone_name,
+ strlen(temp_zone_name) + 1);
+ }
+
+ if (zi != NULL) {
+ *zi = (mach_zone_info_t) {
+ .mzi_count = zone_count_allocated(&zcopy) - cached,
+ .mzi_cur_size = ptoa_64(zone_scale_for_percpu(&zcopy, zcopy.z_wired_cur)),
+ // max_size for zprint is now high-watermark of pages used
+ .mzi_max_size = ptoa_64(zone_scale_for_percpu(&zcopy, zcopy.z_wired_hwm)),
+ .mzi_elem_size = zone_scale_for_percpu(&zcopy, zcopy.z_elem_size),
+ .mzi_alloc_size = ptoa_64(zcopy.z_chunk_pages),
+ .mzi_exhaustible = (uint64_t)zcopy.exhaustible,
+ };
+ zpercpu_foreach(zs, zcopy.z_stats) {
+ zi->mzi_sum_size += zs->zs_mem_allocated;
+ }
+ if (zcopy.collectable) {
+ SET_MZI_COLLECTABLE_BYTES(zi->mzi_collectable,
+ ptoa_64(zone_scale_for_percpu(&zcopy, zcopy.z_wired_empty)));
+ SET_MZI_COLLECTABLE_FLAG(zi->mzi_collectable, TRUE);
+ }
+ }
+
+ return TRUE;
+}
+
+kern_return_t
+task_zone_info(
+ __unused task_t task,
+ __unused mach_zone_name_array_t *namesp,
+ __unused mach_msg_type_number_t *namesCntp,
+ __unused task_zone_info_array_t *infop,
+ __unused mach_msg_type_number_t *infoCntp)
+{
+ return KERN_FAILURE;
+}
+
+kern_return_t
+mach_zone_info(
+ host_priv_t host,
+ mach_zone_name_array_t *namesp,
+ mach_msg_type_number_t *namesCntp,
+ mach_zone_info_array_t *infop,
+ mach_msg_type_number_t *infoCntp)
+{
+ return mach_memory_info(host, namesp, namesCntp, infop, infoCntp, NULL, NULL);
+}
+
+
+kern_return_t
+mach_memory_info(
+ host_priv_t host,
+ mach_zone_name_array_t *namesp,
+ mach_msg_type_number_t *namesCntp,
+ mach_zone_info_array_t *infop,
+ mach_msg_type_number_t *infoCntp,
+ mach_memory_info_array_t *memoryInfop,
+ mach_msg_type_number_t *memoryInfoCntp)
+{
+ mach_zone_name_t *names;
+ vm_offset_t names_addr;
+ vm_size_t names_size;
+
+ mach_zone_info_t *info;
+ vm_offset_t info_addr;
+ vm_size_t info_size;
+
+ mach_memory_info_t *memory_info;
+ vm_offset_t memory_info_addr;
+ vm_size_t memory_info_size;
+ vm_size_t memory_info_vmsize;
+ unsigned int num_info;
+
+ unsigned int max_zones, used_zones, i;
+ mach_zone_name_t *zn;
+ mach_zone_info_t *zi;
+ kern_return_t kr;
+
+ uint64_t zones_collectable_bytes = 0;
+
+ if (host == HOST_NULL) {
+ return KERN_INVALID_HOST;
+ }
+#if CONFIG_DEBUGGER_FOR_ZONE_INFO
+ if (!PE_i_can_has_debugger(NULL)) {
+ return KERN_INVALID_HOST;
+ }
+#endif
+
+ /*
+ * We assume that zones aren't freed once allocated.
+ * We won't pick up any zones that are allocated later.
+ */
+
+ max_zones = os_atomic_load(&num_zones, relaxed);
+
+ names_size = round_page(max_zones * sizeof *names);
+ kr = kmem_alloc_pageable(ipc_kernel_map,
+ &names_addr, names_size, VM_KERN_MEMORY_IPC);
+ if (kr != KERN_SUCCESS) {
+ return kr;
+ }
+ names = (mach_zone_name_t *) names_addr;
+
+ info_size = round_page(max_zones * sizeof *info);
+ kr = kmem_alloc_pageable(ipc_kernel_map,
+ &info_addr, info_size, VM_KERN_MEMORY_IPC);
+ if (kr != KERN_SUCCESS) {
+ kmem_free(ipc_kernel_map,
+ names_addr, names_size);
+ return kr;
+ }
+ info = (mach_zone_info_t *) info_addr;
+
+ zn = &names[0];
+ zi = &info[0];
+
+ used_zones = max_zones;
+ for (i = 0; i < max_zones; i++) {
+ if (!get_zone_info(&(zone_array[i]), zn, zi)) {
+ used_zones--;
+ continue;
+ }
+ zones_collectable_bytes += GET_MZI_COLLECTABLE_BYTES(zi->mzi_collectable);
+ zn++;
+ zi++;
+ }
+
+ *namesp = (mach_zone_name_t *) create_vm_map_copy(names_addr, names_size, used_zones * sizeof *names);
+ *namesCntp = used_zones;
+
+ *infop = (mach_zone_info_t *) create_vm_map_copy(info_addr, info_size, used_zones * sizeof *info);
+ *infoCntp = used_zones;
+
+ num_info = 0;
+ memory_info_addr = 0;
+
+ if (memoryInfop && memoryInfoCntp) {
+ vm_map_copy_t copy;
+ num_info = vm_page_diagnose_estimate();
+ memory_info_size = num_info * sizeof(*memory_info);
+ memory_info_vmsize = round_page(memory_info_size);
+ kr = kmem_alloc_pageable(ipc_kernel_map,
+ &memory_info_addr, memory_info_vmsize, VM_KERN_MEMORY_IPC);
+ if (kr != KERN_SUCCESS) {
+ return kr;
+ }
+
+ kr = vm_map_wire_kernel(ipc_kernel_map, memory_info_addr, memory_info_addr + memory_info_vmsize,
+ VM_PROT_READ | VM_PROT_WRITE, VM_KERN_MEMORY_IPC, FALSE);
+ assert(kr == KERN_SUCCESS);
+
+ memory_info = (mach_memory_info_t *) memory_info_addr;
+ vm_page_diagnose(memory_info, num_info, zones_collectable_bytes);
+
+ kr = vm_map_unwire(ipc_kernel_map, memory_info_addr, memory_info_addr + memory_info_vmsize, FALSE);
+ assert(kr == KERN_SUCCESS);
+
+ kr = vm_map_copyin(ipc_kernel_map, (vm_map_address_t)memory_info_addr,
+ (vm_map_size_t)memory_info_size, TRUE, ©);
+ assert(kr == KERN_SUCCESS);
+
+ *memoryInfop = (mach_memory_info_t *) copy;
+ *memoryInfoCntp = num_info;
+ }
+
+ return KERN_SUCCESS;
+}
+
+kern_return_t
+mach_zone_info_for_zone(
+ host_priv_t host,
+ mach_zone_name_t name,
+ mach_zone_info_t *infop)
+{
+ zone_t zone_ptr;
+
+ if (host == HOST_NULL) {
+ return KERN_INVALID_HOST;
+ }
+#if CONFIG_DEBUGGER_FOR_ZONE_INFO
+ if (!PE_i_can_has_debugger(NULL)) {
+ return KERN_INVALID_HOST;
+ }
+#endif
+
+ if (infop == NULL) {
+ return KERN_INVALID_ARGUMENT;
+ }
+
+ zone_ptr = ZONE_NULL;
+ zone_foreach(z) {
+ /*
+ * Append kalloc heap name to zone name (if zone is used by kalloc)
+ */
+ char temp_zone_name[MAX_ZONE_NAME] = "";
+ snprintf(temp_zone_name, MAX_ZONE_NAME, "%s%s",
+ zone_heap_name(z), z->z_name);
+
+ /* Find the requested zone by name */
+ if (track_this_zone(temp_zone_name, name.mzn_name)) {
+ zone_ptr = z;
+ break;
+ }
+ }
+
+ /* No zones found with the requested zone name */
+ if (zone_ptr == ZONE_NULL) {
+ return KERN_INVALID_ARGUMENT;
+ }
+
+ if (get_zone_info(zone_ptr, NULL, infop)) {
+ return KERN_SUCCESS;
+ }
+ return KERN_FAILURE;
+}
+
+kern_return_t
+mach_zone_info_for_largest_zone(
+ host_priv_t host,
+ mach_zone_name_t *namep,
+ mach_zone_info_t *infop)
+{
+ if (host == HOST_NULL) {
+ return KERN_INVALID_HOST;
+ }
+#if CONFIG_DEBUGGER_FOR_ZONE_INFO
+ if (!PE_i_can_has_debugger(NULL)) {
+ return KERN_INVALID_HOST;
+ }
+#endif
+
+ if (namep == NULL || infop == NULL) {
+ return KERN_INVALID_ARGUMENT;
+ }
+
+ if (get_zone_info(zone_find_largest(), namep, infop)) {
+ return KERN_SUCCESS;
+ }
+ return KERN_FAILURE;
+}
+
+uint64_t
+get_zones_collectable_bytes(void)
+{
+ uint64_t zones_collectable_bytes = 0;
+ mach_zone_info_t zi;
+
+ zone_foreach(z) {
+ if (get_zone_info(z, NULL, &zi)) {
+ zones_collectable_bytes +=
+ GET_MZI_COLLECTABLE_BYTES(zi.mzi_collectable);
+ }
+ }
+
+ return zones_collectable_bytes;
+}
+
+kern_return_t
+mach_zone_get_zlog_zones(
+ host_priv_t host,
+ mach_zone_name_array_t *namesp,
+ mach_msg_type_number_t *namesCntp)
+{
+#if ZONE_ENABLE_LOGGING
+ unsigned int max_zones, logged_zones, i;
+ kern_return_t kr;
+ zone_t zone_ptr;
+ mach_zone_name_t *names;
+ vm_offset_t names_addr;
+ vm_size_t names_size;
+
+ if (host == HOST_NULL) {
+ return KERN_INVALID_HOST;
+ }
+
+ if (namesp == NULL || namesCntp == NULL) {
+ return KERN_INVALID_ARGUMENT;
+ }
+
+ max_zones = os_atomic_load(&num_zones, relaxed);
+
+ names_size = round_page(max_zones * sizeof *names);
+ kr = kmem_alloc_pageable(ipc_kernel_map,
+ &names_addr, names_size, VM_KERN_MEMORY_IPC);
+ if (kr != KERN_SUCCESS) {
+ return kr;
+ }
+ names = (mach_zone_name_t *) names_addr;
+
+ zone_ptr = ZONE_NULL;
+ logged_zones = 0;
+ for (i = 0; i < max_zones; i++) {
+ zone_t z = &(zone_array[i]);
+ assert(z != ZONE_NULL);
+
+ /* Copy out the zone name if zone logging is enabled */
+ if (z->zlog_btlog) {
+ get_zone_info(z, &names[logged_zones], NULL);
+ logged_zones++;
+ }
+ }
+
+ *namesp = (mach_zone_name_t *) create_vm_map_copy(names_addr, names_size, logged_zones * sizeof *names);
+ *namesCntp = logged_zones;
+
+ return KERN_SUCCESS;
+
+#else /* ZONE_ENABLE_LOGGING */
+#pragma unused(host, namesp, namesCntp)
+ return KERN_FAILURE;
+#endif /* ZONE_ENABLE_LOGGING */
+}
+
+kern_return_t
+mach_zone_get_btlog_records(
+ host_priv_t host,
+ mach_zone_name_t name,
+ zone_btrecord_array_t *recsp,
+ mach_msg_type_number_t *recsCntp)
+{
+#if DEBUG || DEVELOPMENT
+ unsigned int numrecs = 0;
+ zone_btrecord_t *recs;
+ kern_return_t kr;
+ zone_t zone_ptr;
+ vm_offset_t recs_addr;
+ vm_size_t recs_size;
+
+ if (host == HOST_NULL) {
+ return KERN_INVALID_HOST;
+ }
+
+ if (recsp == NULL || recsCntp == NULL) {
+ return KERN_INVALID_ARGUMENT;
+ }
+
+ zone_ptr = ZONE_NULL;
+ zone_foreach(z) {
+ /*
+ * Append kalloc heap name to zone name (if zone is used by kalloc)
+ */
+ char temp_zone_name[MAX_ZONE_NAME] = "";
+ snprintf(temp_zone_name, MAX_ZONE_NAME, "%s%s",
+ zone_heap_name(z), z->z_name);
+
+ /* Find the requested zone by name */
+ if (track_this_zone(temp_zone_name, name.mzn_name)) {
+ zone_ptr = z;
+ break;
+ }
+ }
+
+ /* No zones found with the requested zone name */
+ if (zone_ptr == ZONE_NULL) {
+ return KERN_INVALID_ARGUMENT;
+ }
+
+ /* Logging not turned on for the requested zone */
+ if (!DO_LOGGING(zone_ptr)) {
+ return KERN_FAILURE;
+ }
+
+ /* Allocate memory for btlog records */
+ numrecs = (unsigned int)(get_btlog_records_count(zone_ptr->zlog_btlog));
+ recs_size = round_page(numrecs * sizeof *recs);
+
+ kr = kmem_alloc_pageable(ipc_kernel_map, &recs_addr, recs_size, VM_KERN_MEMORY_IPC);
+ if (kr != KERN_SUCCESS) {
+ return kr;
+ }
+
+ /*
+ * We will call get_btlog_records() below which populates this region while holding a spinlock
+ * (the btlog lock). So these pages need to be wired.
+ */
+ kr = vm_map_wire_kernel(ipc_kernel_map, recs_addr, recs_addr + recs_size,
+ VM_PROT_READ | VM_PROT_WRITE, VM_KERN_MEMORY_IPC, FALSE);
+ assert(kr == KERN_SUCCESS);
+
+ recs = (zone_btrecord_t *)recs_addr;
+ get_btlog_records(zone_ptr->zlog_btlog, recs, &numrecs);
+
+ kr = vm_map_unwire(ipc_kernel_map, recs_addr, recs_addr + recs_size, FALSE);
+ assert(kr == KERN_SUCCESS);
+
+ *recsp = (zone_btrecord_t *) create_vm_map_copy(recs_addr, recs_size, numrecs * sizeof *recs);
+ *recsCntp = numrecs;
+
+ return KERN_SUCCESS;
+
+#else /* DEBUG || DEVELOPMENT */
+#pragma unused(host, name, recsp, recsCntp)
+ return KERN_FAILURE;
+#endif /* DEBUG || DEVELOPMENT */
+}
+
+
+#if DEBUG || DEVELOPMENT
+
+kern_return_t
+mach_memory_info_check(void)
+{
+ mach_memory_info_t * memory_info;
+ mach_memory_info_t * info;
+ unsigned int num_info;
+ vm_offset_t memory_info_addr;
+ kern_return_t kr;
+ size_t memory_info_size, memory_info_vmsize;
+ uint64_t top_wired, zonestotal, total;
+
+ num_info = vm_page_diagnose_estimate();
+ memory_info_size = num_info * sizeof(*memory_info);
+ memory_info_vmsize = round_page(memory_info_size);
+ kr = kmem_alloc(kernel_map, &memory_info_addr, memory_info_vmsize, VM_KERN_MEMORY_DIAG);
+ assert(kr == KERN_SUCCESS);
+
+ memory_info = (mach_memory_info_t *) memory_info_addr;
+ vm_page_diagnose(memory_info, num_info, 0);
+
+ top_wired = total = zonestotal = 0;
+ zone_foreach(z) {
+ zonestotal += zone_size_wired(z);
+ }
+
+ for (uint32_t idx = 0; idx < num_info; idx++) {
+ info = &memory_info[idx];
+ if (!info->size) {
+ continue;
+ }
+ if (VM_KERN_COUNT_WIRED == info->site) {
+ top_wired = info->size;
+ }
+ if (VM_KERN_SITE_HIDE & info->flags) {
+ continue;
+ }
+ if (!(VM_KERN_SITE_WIRED & info->flags)) {
+ continue;
+ }
+ total += info->size;
+ }
+ total += zonestotal;
+
+ printf("vm_page_diagnose_check %qd of %qd, zones %qd, short 0x%qx\n",
+ total, top_wired, zonestotal, top_wired - total);
+
+ kmem_free(kernel_map, memory_info_addr, memory_info_vmsize);
+
+ return kr;
+}
+
+extern boolean_t(*volatile consider_buffer_cache_collect)(int);
+
+#endif /* DEBUG || DEVELOPMENT */
+
+kern_return_t
+mach_zone_force_gc(
+ host_t host)
+{
+ if (host == HOST_NULL) {
+ return KERN_INVALID_HOST;
+ }
+
+#if DEBUG || DEVELOPMENT
+ /* Callout to buffer cache GC to drop elements in the apfs zones */
+ if (consider_buffer_cache_collect != NULL) {
+ (void)(*consider_buffer_cache_collect)(0);
+ }
+ zone_gc(ZONE_GC_DRAIN);
+#endif /* DEBUG || DEVELOPMENT */
+ return KERN_SUCCESS;
+}
+
+zone_t
+zone_find_largest(void)
+{
+ uint32_t largest_idx = 0;
+ vm_offset_t largest_size = zone_size_wired(&zone_array[0]);
+
+ zone_index_foreach(i) {
+ vm_offset_t size = zone_size_wired(&zone_array[i]);
+ if (size > largest_size) {
+ largest_idx = i;
+ largest_size = size;
+ }
+ }
+
+ return &zone_array[largest_idx];
+}
+
+#endif /* !ZALLOC_TEST */
+#pragma mark zone creation, configuration, destruction
+#if !ZALLOC_TEST
+
+static zone_t
+zone_init_defaults(zone_id_t zid)
+{
+ zone_t z = &zone_array[zid];
+
+ z->z_wired_max = ~0u;
+ z->collectable = true;
+ z->expandable = true;
+ z->z_submap_idx = Z_SUBMAP_IDX_GENERAL;
+
+ lck_spin_init(&z->z_lock, &zone_locks_grp, LCK_ATTR_NULL);
+ STAILQ_INIT(&z->z_recirc);
+ return z;
+}
+
+static bool
+zone_is_initializing(zone_t z)
+{
+ return !z->z_self && !z->z_destroyed;
+}
+
+void
+zone_set_submap_idx(zone_t zone, unsigned int sub_map_idx)
+{
+ if (!zone_is_initializing(zone)) {
+ panic("%s: called after zone_create()", __func__);
+ }
+ if (sub_map_idx > zone_last_submap_idx) {
+ panic("zone_set_submap_idx(%d) > %d", sub_map_idx, zone_last_submap_idx);
+ }
+ zone->z_submap_idx = sub_map_idx;
+}
+
+void
+zone_set_noexpand(zone_t zone, vm_size_t nelems)
+{
+ if (!zone_is_initializing(zone)) {
+ panic("%s: called after zone_create()", __func__);
+ }
+ zone->expandable = false;
+ zone->z_wired_max = zone_alloc_pages_for_nelems(zone, nelems);
+}
+
+void
+zone_set_exhaustible(zone_t zone, vm_size_t nelems)
+{
+ if (!zone_is_initializing(zone)) {
+ panic("%s: called after zone_create()", __func__);
+ }
+ zone->expandable = false;
+ zone->exhaustible = true;
+ zone->z_wired_max = zone_alloc_pages_for_nelems(zone, nelems);
+}
+
+/**
+ * @function zone_create_find
+ *
+ * @abstract
+ * Finds an unused zone for the given name and element size.
+ *
+ * @param name the zone name
+ * @param size the element size (including redzones, ...)
+ * @param flags the flags passed to @c zone_create*
+ * @param zid_inout the desired zone ID or ZONE_ID_ANY
+ *
+ * @returns a zone to initialize further.
+ */
+static zone_t
+zone_create_find(
+ const char *name,
+ vm_size_t size,
+ zone_create_flags_t flags,
+ zone_id_t *zid_inout)
+{
+ zone_id_t nzones, zid = *zid_inout;
+ zone_t z;
+
+ simple_lock(&all_zones_lock, &zone_locks_grp);
+
+ nzones = (zone_id_t)os_atomic_load(&num_zones, relaxed);
+ assert(num_zones_in_use <= nzones && nzones < MAX_ZONES);
+
+ if (__improbable(nzones < ZONE_ID__FIRST_DYNAMIC)) {
+ /*
+ * The first time around, make sure the reserved zone IDs
+ * have an initialized lock as zone_index_foreach() will
+ * enumerate them.
+ */
+ while (nzones < ZONE_ID__FIRST_DYNAMIC) {
+ zone_init_defaults(nzones++);
+ }
+
+ os_atomic_store(&num_zones, nzones, release);
+ }
+
+ if (zid != ZONE_ID_ANY) {
+ if (zid >= ZONE_ID__FIRST_DYNAMIC) {
+ panic("zone_create: invalid desired zone ID %d for %s",
+ zid, name);
+ }
+ if (flags & ZC_DESTRUCTIBLE) {
+ panic("zone_create: ID %d (%s) must be permanent", zid, name);
+ }
+ if (zone_array[zid].z_self) {
+ panic("zone_create: creating zone ID %d (%s) twice", zid, name);
+ }
+ z = &zone_array[zid];
+ } else {
+ if (flags & ZC_DESTRUCTIBLE) {
+ /*
+ * If possible, find a previously zdestroy'ed zone in the
+ * zone_array that we can reuse.
+ */
+ for (int i = bitmap_first(zone_destroyed_bitmap, MAX_ZONES);
+ i >= 0; i = bitmap_next(zone_destroyed_bitmap, i)) {
+ z = &zone_array[i];
+
+ /*
+ * If the zone name and the element size are the
+ * same, we can just reuse the old zone struct.
+ */
+ if (strcmp(z->z_name, name) || zone_elem_size(z) != size) {
+ continue;
+ }
+ bitmap_clear(zone_destroyed_bitmap, i);
+ z->z_destroyed = false;
+ z->z_self = z;
+ zid = (zone_id_t)i;
+ goto out;
+ }
+ }
+
+ zid = nzones++;
+ z = zone_init_defaults(zid);
+
+ /*
+ * The release barrier pairs with the acquire in
+ * zone_index_foreach() and makes sure that enumeration loops
+ * always see an initialized zone lock.
+ */
+ os_atomic_store(&num_zones, nzones, release);
+ }
+
+out:
+ num_zones_in_use++;
+ simple_unlock(&all_zones_lock);
+
+ *zid_inout = zid;
+ return z;
+}
+
+__abortlike
+static void
+zone_create_panic(const char *name, const char *f1, const char *f2)
+{
+ panic("zone_create: creating zone %s: flag %s and %s are incompatible",
+ name, f1, f2);
+}
+#define zone_create_assert_not_both(name, flags, current_flag, forbidden_flag) \
+ if ((flags) & forbidden_flag) { \
+ zone_create_panic(name, #current_flag, #forbidden_flag); \
+ }
+
+/*
+ * Adjusts the size of the element based on minimum size, alignment
+ * and kasan redzones
+ */
+static vm_size_t
+zone_elem_adjust_size(
+ const char *name __unused,
+ vm_size_t elem_size,
+ zone_create_flags_t flags __unused,
+ uint32_t *redzone __unused)
+{
+ vm_size_t size;
+ /*
+ * Adjust element size for minimum size and pointer alignment
+ */
+ size = (elem_size + sizeof(vm_offset_t) - 1) & -sizeof(vm_offset_t);
+ if (size < ZONE_MIN_ELEM_SIZE) {
+ size = ZONE_MIN_ELEM_SIZE;
+ }
+
+#if KASAN_ZALLOC
+ /*
+ * Expand the zone allocation size to include the redzones.
+ *
+ * For page-multiple zones add a full guard page because they
+ * likely require alignment.
+ */
+ uint32_t redzone_tmp;
+ if (flags & (ZC_KASAN_NOREDZONE | ZC_PERCPU)) {
+ redzone_tmp = 0;
+ } else if ((size & PAGE_MASK) == 0) {
+ if (size != PAGE_SIZE && (flags & ZC_ALIGNMENT_REQUIRED)) {
+ panic("zone_create: zone %s can't provide more than PAGE_SIZE"
+ "alignment", name);
+ }
+ redzone_tmp = PAGE_SIZE;
+ } else if (flags & ZC_ALIGNMENT_REQUIRED) {
+ redzone_tmp = 0;
+ } else {
+ redzone_tmp = KASAN_GUARD_SIZE;
+ }
+ size += redzone_tmp * 2;
+ if (redzone) {
+ *redzone = redzone_tmp;
+ }
+#endif
+ return size;
+}
+
+/*
+ * Returns the allocation chunk size that has least framentation
+ */
+static vm_size_t
+zone_get_min_alloc_granule(
+ vm_size_t elem_size,
+ zone_create_flags_t flags)
+{
+ vm_size_t alloc_granule = PAGE_SIZE;
+ if (flags & ZC_PERCPU) {
+ alloc_granule = PAGE_SIZE * zpercpu_count();
+ if (PAGE_SIZE % elem_size > 256) {
+ panic("zone_create: per-cpu zone has too much fragmentation");
+ }
+ } else if ((elem_size & PAGE_MASK) == 0) {
+ /* zero fragmentation by definition */
+ alloc_granule = elem_size;
+ } else if (alloc_granule % elem_size == 0) {
+ /* zero fragmentation by definition */
+ } else {
+ vm_size_t frag = (alloc_granule % elem_size) * 100 / alloc_granule;
+ vm_size_t alloc_tmp = PAGE_SIZE;
+ while ((alloc_tmp += PAGE_SIZE) <= ZONE_MAX_ALLOC_SIZE) {
+ vm_size_t frag_tmp = (alloc_tmp % elem_size) * 100 / alloc_tmp;
+ if (frag_tmp < frag) {
+ frag = frag_tmp;
+ alloc_granule = alloc_tmp;
+ }
+ }
+ }
+ return alloc_granule;
+}
+
+vm_size_t
+zone_get_foreign_alloc_size(
+ const char *name __unused,
+ vm_size_t elem_size,
+ zone_create_flags_t flags,
+ uint16_t min_pages)
+{
+ vm_size_t adjusted_size = zone_elem_adjust_size(name, elem_size, flags,
+ NULL);
+ vm_size_t alloc_granule = zone_get_min_alloc_granule(adjusted_size,
+ flags);
+ vm_size_t min_size = min_pages * PAGE_SIZE;
+ /*
+ * Round up min_size to a multiple of alloc_granule
+ */
+ return ((min_size + alloc_granule - 1) / alloc_granule)
+ * alloc_granule;
+}
+
+zone_t
+zone_create_ext(
+ const char *name,
+ vm_size_t size,
+ zone_create_flags_t flags,
+ zone_id_t zid,
+ void (^extra_setup)(zone_t))
+{
+ vm_size_t alloc;
+ uint32_t redzone;
+ zone_t z;
+
+ if (size > ZONE_MAX_ALLOC_SIZE) {
+ panic("zone_create: element size too large: %zd", (size_t)size);
+ }
+
+ if (size < 2 * sizeof(vm_size_t)) {
+ /* Elements are too small for kasan. */
+ flags |= ZC_KASAN_NOQUARANTINE | ZC_KASAN_NOREDZONE;
+ }
+
+ size = zone_elem_adjust_size(name, size, flags, &redzone);
+ /*
+ * Allocate the zone slot, return early if we found an older match.
+ */
+ z = zone_create_find(name, size, flags, &zid);
+ if (__improbable(z->z_self)) {
+ /* We found a zone to reuse */
+ return z;
+ }
+
+ /*
+ * Initialize the zone properly.
+ */
+
+ /*
+ * If the kernel is post lockdown, copy the zone name passed in.
+ * Else simply maintain a pointer to the name string as it can only
+ * be a core XNU zone (no unloadable kext exists before lockdown).
+ */
+ if (startup_phase >= STARTUP_SUB_LOCKDOWN) {
+ size_t nsz = MIN(strlen(name) + 1, MACH_ZONE_NAME_MAX_LEN);
+ char *buf = zalloc_permanent(nsz, ZALIGN_NONE);
+ strlcpy(buf, name, nsz);
+ z->z_name = buf;
+ } else {
+ z->z_name = name;
+ }
+ if (__probable(zone_array[ZONE_ID_PERCPU_PERMANENT].z_self)) {
+ z->z_stats = zalloc_percpu_permanent_type(struct zone_stats);
+ } else {
+ /*
+ * zone_init() hasn't run yet, use the storage provided by
+ * zone_stats_startup(), and zone_init() will replace it
+ * with the final value once the PERCPU zone exists.
+ */
+ z->z_stats = __zpcpu_mangle_for_boot(&zone_stats_startup[zone_index(z)]);
+ }
+
+ alloc = zone_get_min_alloc_granule(size, flags);
+
+ if (flags & ZC_KALLOC_HEAP) {
+ size_t rem = (alloc % size) / (alloc / size);
+
+ /*
+ * Try to grow the elements size and spread them more if the remaining
+ * space is large enough.
+ */
+ size += rem & ~(KALLOC_MINALIGN - 1);
+ }
+
+ z->z_elem_size = (uint16_t)size;
+ z->z_chunk_pages = (uint16_t)atop(alloc);
+ if (flags & ZC_PERCPU) {
+ z->z_chunk_elems = (uint16_t)(PAGE_SIZE / z->z_elem_size);
+ } else {
+ z->z_chunk_elems = (uint16_t)(alloc / z->z_elem_size);
+ }
+ if (zone_element_idx(zone_element_encode(0,
+ z->z_chunk_elems - 1, ZPM_AUTO)) != z->z_chunk_elems - 1) {
+ panic("zone_element_encode doesn't work for zone [%s]", name);
+ }
+
+#if KASAN_ZALLOC
+ z->z_kasan_redzone = redzone;
+ if (strncmp(name, "fakestack.", sizeof("fakestack.") - 1) == 0) {
+ z->kasan_fakestacks = true;
+ }
+#endif
+
+ /*
+ * Handle KPI flags
+ */
+#if __LP64__
+ if (flags & ZC_SEQUESTER) {
+ z->z_va_sequester = true;
+ }
+#endif
+ /* ZC_CACHING applied after all configuration is done */
+ if (flags & ZC_NOCACHING) {
+ z->z_nocaching = true;
+ }
+
+ if (flags & ZC_PERCPU) {
+ /*
+ * ZC_ZFREE_CLEARMEM is forced because per-cpu zones allow for
+ * pointer-sized allocations which poisoning doesn't support.
+ */
+ zone_create_assert_not_both(name, flags, ZC_PERCPU, ZC_ALLOW_FOREIGN);
+ z->z_percpu = true;
+ z->gzalloc_exempt = true;
+ z->z_free_zeroes = true;
+ }
+ if (flags & ZC_ZFREE_CLEARMEM) {
+ z->z_free_zeroes = true;
+ }
+ if (flags & ZC_NOGC) {
+ z->collectable = false;
+ }
+ if (flags & ZC_NOENCRYPT) {
+ z->z_noencrypt = true;
+ }
+ if (flags & ZC_ALIGNMENT_REQUIRED) {
+ z->alignment_required = true;
+ }
+ if (flags & ZC_NOGZALLOC) {
+ z->gzalloc_exempt = true;
+ }
+ if (flags & ZC_NOCALLOUT) {
+ z->no_callout = true;
+ }
+ if (flags & ZC_DESTRUCTIBLE) {
+ zone_create_assert_not_both(name, flags, ZC_DESTRUCTIBLE, ZC_ALLOW_FOREIGN);
+ z->z_destructible = true;
+ }
+
+ /*
+ * Handle Internal flags
+ */
+ if (flags & ZC_ALLOW_FOREIGN) {
+ z->z_allows_foreign = true;
+ }
+ if ((ZSECURITY_OPTIONS_SUBMAP_USER_DATA & zsecurity_options) &&
+ (flags & ZC_DATA_BUFFERS)) {
+ z->z_submap_idx = Z_SUBMAP_IDX_BAG_OF_BYTES;
+ }
+ if (flags & ZC_KASAN_NOQUARANTINE) {
+ z->kasan_noquarantine = true;
+ }
+ /* ZC_KASAN_NOREDZONE already handled */
+
+ /*
+ * Then if there's extra tuning, do it
+ */
+ if (extra_setup) {
+ extra_setup(z);
+ }
+
+ /*
+ * Configure debugging features
+ */
+#if CONFIG_GZALLOC
+ gzalloc_zone_init(z); /* might set z->gzalloc_tracked */
+ if (z->gzalloc_tracked) {
+ z->z_nocaching = true;
+ }
+#endif
+#if ZONE_ENABLE_LOGGING
+ if (!z->gzalloc_tracked && num_zones_logged < max_num_zones_to_log) {
+ /*
+ * Check for and set up zone leak detection if requested via boot-args.
+ * might set z->zone_logging
+ */
+ zone_setup_logging(z);
+ }
+#endif /* ZONE_ENABLE_LOGGING */
+#if VM_MAX_TAG_ZONES
+ if (!z->gzalloc_tracked && z->kalloc_heap && zone_tagging_on) {
+ static int tag_zone_index;
+ vm_offset_t esize = zone_elem_size(z);
+ z->tags = true;
+ z->tags_inline = (((page_size + esize - 1) / esize) <=
+ (sizeof(uint32_t) / sizeof(uint16_t)));
+ z->tag_zone_index = os_atomic_inc_orig(&tag_zone_index, relaxed);
+ assert(z->tag_zone_index < VM_MAX_TAG_ZONES);
+ }
+#endif
+
+ /*
+ * Finally, fixup properties based on security policies, boot-args, ...
+ */
+ if ((ZSECURITY_OPTIONS_SUBMAP_USER_DATA & zsecurity_options) &&
+ z->kalloc_heap == KHEAP_ID_DATA_BUFFERS) {
+ z->z_submap_idx = Z_SUBMAP_IDX_BAG_OF_BYTES;
+ }
+#if __LP64__
+ if ((ZSECURITY_OPTIONS_SEQUESTER & zsecurity_options) &&
+ (flags & ZC_NOSEQUESTER) == 0 &&
+ z->z_submap_idx == Z_SUBMAP_IDX_GENERAL) {
+ z->z_va_sequester = true;
+ }
+#endif
+ /*
+ * Clear entire element for non data zones and upto zp_min_size for
+ * data zones.
+ */
+ if (z->z_submap_idx != Z_SUBMAP_IDX_BAG_OF_BYTES) {
+ z->z_free_zeroes = true;
+ } else if (size <= zp_min_size) {
+ z->z_free_zeroes = true;
+ }
+
+ if ((flags & ZC_CACHING) && !z->z_nocaching) {
+ /*
+ * If zcache hasn't been initialized yet, remember our decision,
+ *
+ * zone_enable_caching() will be called again by
+ * zcache_bootstrap(), while the system is still single
+ * threaded, to build the missing caches.
+ */
+ if (__probable(zc_magazine_zone)) {
+ zone_enable_caching(z);
+ } else {
+ z->z_pcpu_cache =
+ __zpcpu_mangle_for_boot(&zone_cache_startup[zid]);
+ }
+ }
+
+ if (zp_factor != 0 && !z->z_free_zeroes) {
+ if (__probable(zone_array[ZONE_ID_PERCPU_PERMANENT].z_self)) {
+ zpercpu_foreach(zs, z->z_stats) {
+ zs->zs_poison_seqno = zone_poison_count_init(z);
+ }
+ } else {
+ zone_stats_startup[zid].zs_poison_seqno =
+ zone_poison_count_init(z);
+ }
+ }
+
+ zone_lock(z);
+ z->z_self = z;
+ zone_unlock(z);
+
+ return z;
+}
+
+__startup_func
+void
+zone_create_startup(struct zone_create_startup_spec *spec)
+{
+ *spec->z_var = zone_create_ext(spec->z_name, spec->z_size,
+ spec->z_flags, spec->z_zid, spec->z_setup);
+}
+
+/*
+ * The 4 first field of a zone_view and a zone alias, so that the zone_or_view_t
+ * union works. trust but verify.
+ */
+#define zalloc_check_zov_alias(f1, f2) \
+ static_assert(offsetof(struct zone, f1) == offsetof(struct zone_view, f2))
+zalloc_check_zov_alias(z_self, zv_zone);
+zalloc_check_zov_alias(z_stats, zv_stats);
+zalloc_check_zov_alias(z_name, zv_name);
+zalloc_check_zov_alias(z_views, zv_next);
+#undef zalloc_check_zov_alias
+
+__startup_func
+void
+zone_view_startup_init(struct zone_view_startup_spec *spec)
+{
+ struct kalloc_heap *heap = NULL;
+ zone_view_t zv = spec->zv_view;
+ zone_t z;
+
+ switch (spec->zv_heapid) {
+ case KHEAP_ID_DEFAULT:
+ heap = KHEAP_DEFAULT;
+ break;
+ case KHEAP_ID_DATA_BUFFERS:
+ heap = KHEAP_DATA_BUFFERS;
+ break;
+ case KHEAP_ID_KEXT:
+ heap = KHEAP_KEXT;
+ break;
+ default:
+ heap = NULL;
+ }
+
+ if (heap) {
+ z = kalloc_heap_zone_for_size(heap, spec->zv_size);
+ assert(z);
+ } else {
+ z = spec->zv_zone;
+ assert(spec->zv_size <= zone_elem_size(z));
+ }
+
+ zv->zv_zone = z;
+ zv->zv_stats = zalloc_percpu_permanent_type(struct zone_stats);
+ zv->zv_next = z->z_views;
+ if (z->z_views == NULL && z->kalloc_heap == KHEAP_ID_NONE) {
+ /*
+ * count the raw view for zones not in a heap,
+ * kalloc_heap_init() already counts it for its members.
+ */
+ zone_view_count += 2;
+ } else {
+ zone_view_count += 1;
+ }
+ z->z_views = zv;
+}
+
+zone_t
+zone_create(
+ const char *name,
+ vm_size_t size,
+ zone_create_flags_t flags)
+{
+ return zone_create_ext(name, size, flags, ZONE_ID_ANY, NULL);
+}
+
+zone_t
+zinit(
+ vm_size_t size, /* the size of an element */
+ vm_size_t max, /* maximum memory to use */
+ vm_size_t alloc __unused, /* allocation size */
+ const char *name) /* a name for the zone */
+{
+ zone_t z = zone_create(name, size, ZC_DESTRUCTIBLE);
+ z->z_wired_max = zone_alloc_pages_for_nelems(z, max / size);
+ return z;
+}
+
+void
+zdestroy(zone_t z)
+{
+ unsigned int zindex = zone_index(z);
+
+ current_thread()->options |= TH_OPT_ZONE_PRIV;
+ lck_mtx_lock(&zone_gc_lock);
+
+ zone_reclaim(z, ZONE_RECLAIM_DESTROY);
+
+ lck_mtx_unlock(&zone_gc_lock);
+ current_thread()->options &= ~TH_OPT_ZONE_PRIV;
+
+#if CONFIG_GZALLOC
+ if (__improbable(z->gzalloc_tracked)) {
+ /* If the zone is gzalloc managed dump all the elements in the free cache */
+ gzalloc_empty_free_cache(z);
+ }
+#endif
+
+ zone_lock(z);
+
+ while (!zone_pva_is_null(z->z_pageq_va)) {
+ struct zone_page_metadata *meta;
+ vm_offset_t free_addr;
+
+ zone_counter_sub(z, z_va_cur, z->z_percpu ? 1 : z->z_chunk_pages);
+ meta = zone_meta_queue_pop_native(z, &z->z_pageq_va, &free_addr);
+ assert(meta->zm_chunk_len <= ZM_CHUNK_LEN_MAX);
+ bzero(meta, sizeof(*meta) * z->z_chunk_pages);
+ zone_unlock(z);
+ kmem_free(zone_submap(z), free_addr, ptoa(z->z_chunk_pages));
+ zone_lock(z);
+ }
+
+#if !KASAN_ZALLOC
+ /* Assert that all counts are zero */
+ if (z->z_elems_avail || z->z_elems_free ||
+ zone_size_wired(z) || z->z_va_cur) {
+ panic("zdestroy: Zone %s%s isn't empty at zdestroy() time",
+ zone_heap_name(z), z->z_name);
+ }
+
+ /* consistency check: make sure everything is indeed empty */
+ assert(zone_pva_is_null(z->z_pageq_empty));
+ assert(zone_pva_is_null(z->z_pageq_partial));
+ assert(zone_pva_is_null(z->z_pageq_full));
+ assert(zone_pva_is_null(z->z_pageq_va));
+#endif
+
+ zone_unlock(z);
+
+ simple_lock(&all_zones_lock, &zone_locks_grp);
+
+ assert(!bitmap_test(zone_destroyed_bitmap, zindex));
+ /* Mark the zone as empty in the bitmap */
+ bitmap_set(zone_destroyed_bitmap, zindex);
+ num_zones_in_use--;
+ assert(num_zones_in_use > 0);
+
+ simple_unlock(&all_zones_lock);
+}
+
+#endif /* !ZALLOC_TEST */
+#pragma mark zalloc module init
+#if !ZALLOC_TEST
+
+/*
+ * Initialize the "zone of zones" which uses fixed memory allocated
+ * earlier in memory initialization. zone_bootstrap is called
+ * before zone_init.
+ */
+__startup_func
+void
+zone_bootstrap(void)
+{
+ /* Validate struct zone_packed_virtual_address expectations */
+ static_assert((intptr_t)VM_MIN_KERNEL_ADDRESS < 0, "the top bit must be 1");
+ if (VM_KERNEL_POINTER_SIGNIFICANT_BITS - PAGE_SHIFT > 31) {
+ panic("zone_pva_t can't pack a kernel page address in 31 bits");
+ }
+
+ zpercpu_early_count = ml_early_cpu_max_number() + 1;
+
+ /* Set up zone element poisoning */
+ zp_bootstrap();
/*
- * We assume that zones aren't freed once allocated.
- * We won't pick up any zones that are allocated later.
+ * the KASAN quarantine for kalloc doesn't understand heaps
+ * and trips the heap confusion panics. At the end of the day,
+ * all these security measures are double duty with KASAN.
+ *
+ * On 32bit kernels, these protections are just too expensive.
*/
+#if !defined(__LP64__) || KASAN_ZALLOC
+ zsecurity_options &= ~ZSECURITY_OPTIONS_SEQUESTER;
+ zsecurity_options &= ~ZSECURITY_OPTIONS_SUBMAP_USER_DATA;
+ zsecurity_options &= ~ZSECURITY_OPTIONS_SEQUESTER_KEXT_KALLOC;
+#endif
+
+ thread_call_setup_with_options(&zone_expand_callout,
+ zone_expand_async, NULL, THREAD_CALL_PRIORITY_HIGH,
+ THREAD_CALL_OPTIONS_ONCE);
- simple_lock(&all_zones_lock);
-#ifdef ppc
- max_zones = num_zones + 4;
+ thread_call_setup_with_options(&zone_defrag_callout,
+ zone_defrag_async, NULL, THREAD_CALL_PRIORITY_USER,
+ THREAD_CALL_OPTIONS_ONCE);
+}
+
+#if __LP64__
+#if ARM_LARGE_MEMORY || __x86_64__
+#define ZONE_MAP_VIRTUAL_SIZE_LP64 (128ULL * 1024ULL * 1024 * 1024)
#else
- max_zones = num_zones + 3; /* ATN: count the number below!! */
+#define ZONE_MAP_VIRTUAL_SIZE_LP64 (32ULL * 1024ULL * 1024 * 1024)
#endif
- z = first_zone;
- simple_unlock(&all_zones_lock);
+#endif /* __LP64__ */
+
+#define ZONE_GUARD_SIZE (64UL << 10)
+
+#if __LP64__
+static inline vm_offset_t
+zone_restricted_va_max(void)
+{
+ vm_offset_t compressor_max = VM_PACKING_MAX_PACKABLE(C_SLOT_PACKED_PTR);
+ vm_offset_t vm_page_max = VM_PACKING_MAX_PACKABLE(VM_PAGE_PACKED_PTR);
+
+ return trunc_page(MIN(compressor_max, vm_page_max));
+}
+#endif
+
+__startup_func
+static void
+zone_tunables_fixup(void)
+{
+ if (zone_map_jetsam_limit == 0 || zone_map_jetsam_limit > 100) {
+ zone_map_jetsam_limit = ZONE_MAP_JETSAM_LIMIT_DEFAULT;
+ }
+ if (zc_magazine_size > PAGE_SIZE / ZONE_MIN_ELEM_SIZE) {
+ zc_magazine_size = (uint16_t)(PAGE_SIZE / ZONE_MIN_ELEM_SIZE);
+ }
+}
+STARTUP(TUNABLES, STARTUP_RANK_MIDDLE, zone_tunables_fixup);
+
+__startup_func
+static vm_size_t
+zone_phys_size_max(void)
+{
+ vm_size_t zsize;
+ vm_size_t zsizearg;
- if (max_zones <= *namesCntp) {
- /* use in-line memory */
- names_size = *namesCntp * sizeof *names;
- names = *namesp;
+ if (PE_parse_boot_argn("zsize", &zsizearg, sizeof(zsizearg))) {
+ zsize = zsizearg * (1024ULL * 1024);
} else {
- names_size = round_page(max_zones * sizeof *names);
- kr = kmem_alloc_pageable(ipc_kernel_map,
- &names_addr, names_size);
- if (kr != KERN_SUCCESS)
- return kr;
- names = (zone_name_t *) names_addr;
+ /* Set target zone size as 1/4 of physical memory */
+ zsize = (vm_size_t)(sane_size >> 2);
+#if defined(__LP64__)
+ zsize += zsize >> 1;
+#endif /* __LP64__ */
+ }
+
+ if (zsize < CONFIG_ZONE_MAP_MIN) {
+ zsize = CONFIG_ZONE_MAP_MIN; /* Clamp to min */
}
+ if (zsize > sane_size >> 1) {
+ zsize = (vm_size_t)(sane_size >> 1); /* Clamp to half of RAM max */
+ }
+ if (zsizearg == 0 && zsize > ZONE_MAP_MAX) {
+ /* if zsize boot-arg not present and zsize exceeds platform maximum, clip zsize */
+ printf("NOTE: zonemap size reduced from 0x%lx to 0x%lx\n",
+ (uintptr_t)zsize, (uintptr_t)ZONE_MAP_MAX);
+ zsize = ZONE_MAP_MAX;
+ }
+
+ return (vm_size_t)trunc_page(zsize);
+}
- if (max_zones <= *infoCntp) {
- /* use in-line memory */
- info_size = *infoCntp * sizeof *info;
- info = *infop;
+__options_decl(zone_init_allocate_flags_t, unsigned, {
+ ZIA_NONE = 0x00000000,
+ ZIA_REPLACE = 0x00000001, /* replace a previous non permanent range */
+ ZIA_RANDOM = 0x00000002, /* place at a random address */
+ ZIA_PERMANENT = 0x00000004, /* permanent allocation */
+ ZIA_GUARD = 0x00000008, /* will be used as a guard */
+});
+
+__startup_func
+static struct zone_map_range
+zone_init_allocate_va(vm_map_address_t addr, vm_size_t size,
+ zone_init_allocate_flags_t flags)
+{
+ vm_map_kernel_flags_t vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
+ int vm_alloc_flags = 0;
+ struct zone_map_range r;
+ kern_return_t kr;
+
+ if (flags & ZIA_REPLACE) {
+ vm_alloc_flags |= VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE;
} else {
- info_size = round_page(max_zones * sizeof *info);
- kr = kmem_alloc_pageable(ipc_kernel_map,
- &info_addr, info_size);
- if (kr != KERN_SUCCESS) {
- if (names != *namesp)
- kmem_free(ipc_kernel_map,
- names_addr, names_size);
- return kr;
+ vm_alloc_flags |= VM_FLAGS_ANYWHERE;
+ }
+ if (flags & ZIA_RANDOM) {
+ vm_alloc_flags |= VM_FLAGS_RANDOM_ADDR;
+ }
+ if (flags & ZIA_PERMANENT) {
+ vmk_flags.vmkf_permanent = true;
+ }
+
+ vm_object_reference(kernel_object);
+
+ kr = vm_map_enter(kernel_map, &addr, size, 0,
+ vm_alloc_flags, vmk_flags, VM_KERN_MEMORY_ZONE,
+ kernel_object, 0, FALSE,
+ (flags & ZIA_GUARD) ? VM_PROT_NONE : VM_PROT_DEFAULT,
+ (flags & ZIA_GUARD) ? VM_PROT_NONE : VM_PROT_DEFAULT,
+ VM_INHERIT_NONE);
+
+ if (KERN_SUCCESS != kr) {
+ panic("vm_map_enter(0x%zx) failed: %d", (size_t)size, kr);
+ }
+
+ r.min_address = (vm_offset_t)addr;
+ r.max_address = (vm_offset_t)addr + size;
+ return r;
+}
+
+__startup_func
+static void
+zone_submap_init(
+ vm_offset_t *submap_min,
+ unsigned idx,
+ uint64_t zone_sub_map_numer,
+ uint64_t *remaining_denom,
+ vm_offset_t *remaining_size,
+ vm_size_t guard_size)
+{
+ vm_offset_t submap_start, submap_end;
+ vm_size_t submap_size;
+ vm_map_t submap;
+ kern_return_t kr;
+
+ submap_size = trunc_page(zone_sub_map_numer * *remaining_size /
+ *remaining_denom);
+ submap_start = *submap_min;
+ submap_end = submap_start + submap_size;
+
+#if defined(__LP64__)
+ if (idx == Z_SUBMAP_IDX_VA_RESTRICTED) {
+ vm_offset_t restricted_va_max = zone_restricted_va_max();
+ if (submap_end > restricted_va_max) {
+#if DEBUG || DEVELOPMENT
+ printf("zone_init: submap[%d] clipped to %zdM of %zdM\n", idx,
+ (size_t)(restricted_va_max - submap_start) >> 20,
+ (size_t)submap_size >> 20);
+#endif /* DEBUG || DEVELOPMENT */
+ guard_size += submap_end - restricted_va_max;
+ *remaining_size -= submap_end - restricted_va_max;
+ submap_end = restricted_va_max;
+ submap_size = restricted_va_max - submap_start;
}
- info = (zone_info_t *) info_addr;
+ vm_packing_verify_range("vm_compressor",
+ submap_start, submap_end, VM_PACKING_PARAMS(C_SLOT_PACKED_PTR));
+ vm_packing_verify_range("vm_page",
+ submap_start, submap_end, VM_PACKING_PARAMS(VM_PAGE_PACKED_PTR));
+ }
+#endif /* defined(__LP64__) */
+
+ vm_map_kernel_flags_t vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
+ vmk_flags.vmkf_permanent = TRUE;
+ kr = kmem_suballoc(kernel_map, submap_min, submap_size,
+ FALSE, VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE, vmk_flags,
+ VM_KERN_MEMORY_ZONE, &submap);
+ if (kr != KERN_SUCCESS) {
+ panic("kmem_suballoc(kernel_map[%d] %p:%p) failed: %d",
+ idx, (void *)submap_start, (void *)submap_end, kr);
}
- zn = &names[0];
- zi = &info[0];
- for (i = 0; i < num_zones; i++) {
- struct zone zcopy;
+#if DEBUG || DEVELOPMENT
+ printf("zone_init: submap[%d] %p:%p (%zuM)\n",
+ idx, (void *)submap_start, (void *)submap_end,
+ (size_t)submap_size >> 20);
+#endif /* DEBUG || DEVELOPMENT */
- assert(z != ZONE_NULL);
+ zone_init_allocate_va(submap_end, guard_size,
+ ZIA_PERMANENT | ZIA_GUARD | ZIA_REPLACE);
- lock_zone(z);
- zcopy = *z;
- unlock_zone(z);
+ zone_submaps[idx] = submap;
+ *submap_min = submap_end + guard_size;
+ *remaining_size -= submap_size;
+ *remaining_denom -= zone_sub_map_numer;
+}
- simple_lock(&all_zones_lock);
- z = z->next_zone;
- simple_unlock(&all_zones_lock);
+/*
+ * Allocate metadata array and migrate foreign initial metadata.
+ *
+ * So that foreign pages and native pages have the same scheme,
+ * we allocate VA space that covers both foreign and native pages.
+ */
+__startup_func
+static void
+zone_metadata_init(void)
+{
+ struct zone_map_range r0 = zone_info.zi_map_range[0];
+ struct zone_map_range r1 = zone_info.zi_map_range[1];
+ struct zone_map_range mr, br;
+ vm_size_t meta_size, bits_size, foreign_base;
+ vm_offset_t hstart, hend;
+
+ if (r0.min_address > r1.min_address) {
+ r0 = zone_info.zi_map_range[1];
+ r1 = zone_info.zi_map_range[0];
+ }
- /* assuming here the name data is static */
- (void) strncpy(zn->zn_name, zcopy.zone_name,
- sizeof zn->zn_name);
+ meta_size = round_page(atop(r1.max_address - r0.min_address) *
+ sizeof(struct zone_page_metadata)) + ZONE_GUARD_SIZE * 2;
- zi->zi_count = zcopy.count;
- zi->zi_cur_size = zcopy.cur_size;
- zi->zi_max_size = zcopy.max_size;
- zi->zi_elem_size = zcopy.elem_size;
- zi->zi_alloc_size = zcopy.alloc_size;
- zi->zi_exhaustible = zcopy.exhaustible;
- zi->zi_collectable = zcopy.collectable;
+ /*
+ * Allocations can't be smaller than 8 bytes, which is 128b / 16B per 1k
+ * of physical memory (16M per 1G).
+ *
+ * Let's preallocate for the worst to avoid weird panics.
+ */
+ bits_size = round_page(16 * (ptoa(zone_phys_mapped_max_pages) >> 10));
- zn++;
- zi++;
+ /*
+ * Compute the size of the "hole" in the middle of the range.
+ *
+ * If it is smaller than 256k, just leave it be, with this layout:
+ *
+ * [G][ r0 meta ][ hole ][ r1 meta ][ bits ][G]
+ *
+ * else punch a hole with guard pages around the hole, and place the
+ * bits in the hole if it fits, or after r1 otherwise, yielding either
+ * of the following layouts:
+ *
+ * |__________________hend____________|
+ * |__hstart_| |
+ * [G][ r0 meta ][ bits ][G]..........[G][ r1 meta ][G]
+ * [G][ r0 meta ][G]..................[G][ r1 meta ][ bits ][G]
+ */
+ hstart = round_page(atop(r0.max_address - r0.min_address) *
+ sizeof(struct zone_page_metadata));
+ hend = trunc_page(atop(r1.min_address - r0.min_address) *
+ sizeof(struct zone_page_metadata));
+
+ if (hstart >= hend || hend - hstart < (256ul << 10)) {
+ mr = zone_init_allocate_va(0, meta_size + bits_size,
+ ZIA_PERMANENT | ZIA_RANDOM);
+ mr.min_address += ZONE_GUARD_SIZE;
+ mr.max_address -= ZONE_GUARD_SIZE;
+ br.max_address = mr.max_address;
+ mr.max_address -= bits_size;
+ br.min_address = mr.max_address;
+
+#if DEBUG || DEVELOPMENT
+ printf("zone_init: metadata %p:%p (%zuK)\n",
+ (void *)mr.min_address, (void *)mr.max_address,
+ (size_t)zone_range_size(&mr) >> 10);
+ printf("zone_init: metabits %p:%p (%zuK)\n",
+ (void *)br.min_address, (void *)br.max_address,
+ (size_t)zone_range_size(&br) >> 10);
+#endif /* DEBUG || DEVELOPMENT */
+ } else {
+ vm_size_t size, alloc_size = meta_size;
+ vm_offset_t base;
+ bool bits_in_middle = true;
+
+ if (hend - hstart - 2 * ZONE_GUARD_SIZE < bits_size) {
+ alloc_size += bits_size;
+ bits_in_middle = false;
+ }
+
+ mr = zone_init_allocate_va(0, alloc_size, ZIA_RANDOM);
+
+ base = mr.min_address;
+ size = ZONE_GUARD_SIZE + hstart + ZONE_GUARD_SIZE;
+ if (bits_in_middle) {
+ size += bits_size;
+ br.min_address = base + ZONE_GUARD_SIZE + hstart;
+ br.max_address = br.min_address + bits_size;
+ }
+ zone_init_allocate_va(base, size, ZIA_PERMANENT | ZIA_REPLACE);
+
+ base += size;
+ size = mr.min_address + hend - base;
+ kmem_free(kernel_map, base, size);
+
+ base = mr.min_address + hend;
+ size = mr.max_address - base;
+ zone_init_allocate_va(base, size, ZIA_PERMANENT | ZIA_REPLACE);
+
+ mr.min_address += ZONE_GUARD_SIZE;
+ mr.max_address -= ZONE_GUARD_SIZE;
+ if (!bits_in_middle) {
+ br.max_address = mr.max_address;
+ mr.max_address -= bits_size;
+ br.min_address = mr.max_address;
+ }
+
+#if DEBUG || DEVELOPMENT
+ printf("zone_init: metadata0 %p:%p (%zuK)\n",
+ (void *)mr.min_address, (void *)(mr.min_address + hstart),
+ (size_t)hstart >> 10);
+ printf("zone_init: metadata1 %p:%p (%zuK)\n",
+ (void *)(mr.min_address + hend), (void *)mr.max_address,
+ (size_t)(zone_range_size(&mr) - hend) >> 10);
+ printf("zone_init: metabits %p:%p (%zuK)\n",
+ (void *)br.min_address, (void *)br.max_address,
+ (size_t)zone_range_size(&br) >> 10);
+#endif /* DEBUG || DEVELOPMENT */
}
- strcpy(zn->zn_name, "kernel_stacks");
- stack_fake_zone_info(&zi->zi_count, &zi->zi_cur_size, &zi->zi_max_size, &zi->zi_elem_size,
- &zi->zi_alloc_size, &zi->zi_collectable, &zi->zi_exhaustible);
- zn++;
- zi++;
-#ifdef ppc
- strcpy(zn->zn_name, "save_areas");
- save_fake_zone_info(&zi->zi_count, &zi->zi_cur_size, &zi->zi_max_size, &zi->zi_elem_size,
- &zi->zi_alloc_size, &zi->zi_collectable, &zi->zi_exhaustible);
- zn++;
- zi++;
-
- strcpy(zn->zn_name, "pmap_mappings");
- mapping_fake_zone_info(&zi->zi_count, &zi->zi_cur_size, &zi->zi_max_size, &zi->zi_elem_size,
- &zi->zi_alloc_size, &zi->zi_collectable, &zi->zi_exhaustible);
- zn++;
- zi++;
-#endif
-#ifdef i386
- strcpy(zn->zn_name, "page_tables");
- pt_fake_zone_info(&zi->zi_count, &zi->zi_cur_size, &zi->zi_max_size, &zi->zi_elem_size,
- &zi->zi_alloc_size, &zi->zi_collectable, &zi->zi_exhaustible);
- zn++;
- zi++;
+ br.min_address = (br.min_address + ZBA_CHUNK_SIZE - 1) & -ZBA_CHUNK_SIZE;
+ br.max_address = br.max_address & -ZBA_CHUNK_SIZE;
+
+ zone_info.zi_meta_range = mr;
+ zone_info.zi_bits_range = br;
+
+ /*
+ * Migrate the original static metadata into its new location.
+ */
+ zone_info.zi_meta_base = (struct zone_page_metadata *)mr.min_address -
+ zone_pva_from_addr(r0.min_address).packed_address;
+ foreign_base = zone_info.zi_map_range[ZONE_ADDR_FOREIGN].min_address;
+ zone_meta_populate(foreign_base, zone_foreign_size());
+ memcpy(zone_meta_from_addr(foreign_base),
+ zone_foreign_meta_array_startup,
+ atop(zone_foreign_size()) * sizeof(struct zone_page_metadata));
+
+ zba_populate(0);
+ memcpy(zba_base_header(), zba_chunk_startup,
+ sizeof(zba_chunk_startup));
+}
+
+/* Global initialization of Zone Allocator.
+ * Runs after zone_bootstrap.
+ */
+__startup_func
+static void
+zone_init(void)
+{
+ vm_size_t zone_map_size;
+ vm_size_t remaining_size;
+ vm_offset_t submap_min = 0;
+ uint64_t denom = 0;
+ uint64_t submap_ratios[Z_SUBMAP_IDX_COUNT] = {
+#ifdef __LP64__
+ [Z_SUBMAP_IDX_VA_RESTRICTED] = 20,
+#else
+ [Z_SUBMAP_IDX_VA_RESERVE] = 10,
+#endif /* defined(__LP64__) */
+ [Z_SUBMAP_IDX_GENERAL] = 40,
+ [Z_SUBMAP_IDX_BAG_OF_BYTES] = 40,
+ };
+
+ if (ZSECURITY_OPTIONS_SUBMAP_USER_DATA & zsecurity_options) {
+ zone_last_submap_idx = Z_SUBMAP_IDX_BAG_OF_BYTES;
+ } else {
+ zone_last_submap_idx = Z_SUBMAP_IDX_GENERAL;
+ }
+ zone_phys_mapped_max_pages = (uint32_t)atop(zone_phys_size_max());
+
+ for (unsigned idx = 0; idx <= zone_last_submap_idx; idx++) {
+#if DEBUG || DEVELOPMENT
+ char submap_name[1 + sizeof("submap")];
+ snprintf(submap_name, sizeof(submap_name), "submap%d", idx);
+ PE_parse_boot_argn(submap_name, &submap_ratios[idx], sizeof(uint64_t));
#endif
+ denom += submap_ratios[idx];
+ }
- strcpy(zn->zn_name, "kalloc.large");
- kalloc_fake_zone_info(&zi->zi_count, &zi->zi_cur_size, &zi->zi_max_size, &zi->zi_elem_size,
- &zi->zi_alloc_size, &zi->zi_collectable, &zi->zi_exhaustible);
+#if __LP64__
+ zone_map_size = ZONE_MAP_VIRTUAL_SIZE_LP64;
+#else
+ zone_map_size = ptoa(zone_phys_mapped_max_pages *
+ (denom + submap_ratios[Z_SUBMAP_IDX_VA_RESERVE]) / denom);
+#endif
- if (names != *namesp) {
- vm_size_t used;
- vm_map_copy_t copy;
+ remaining_size = zone_map_size -
+ ZONE_GUARD_SIZE * (zone_last_submap_idx + 1);
- used = max_zones * sizeof *names;
+ /*
+ * And now allocate the various pieces of VA and submaps.
+ *
+ * Make a first allocation of contiguous VA, that we'll deallocate,
+ * and we'll carve-out memory in that range again linearly.
+ * The kernel is stil single threaded at this stage.
+ */
- if (used != names_size)
- bzero((char *) (names_addr + used), names_size - used);
+ struct zone_map_range *map_range =
+ &zone_info.zi_map_range[ZONE_ADDR_NATIVE];
- kr = vm_map_copyin(ipc_kernel_map, (vm_map_address_t)names_addr,
- (vm_map_size_t)names_size, TRUE, ©);
- assert(kr == KERN_SUCCESS);
+ *map_range = zone_init_allocate_va(0, zone_map_size, ZIA_NONE);
+ submap_min = map_range->min_address;
- *namesp = (zone_name_t *) copy;
+ /*
+ * Allocate the submaps
+ */
+ for (unsigned idx = 0; idx <= zone_last_submap_idx; idx++) {
+ zone_submap_init(&submap_min, idx, submap_ratios[idx],
+ &denom, &remaining_size, ZONE_GUARD_SIZE);
}
- *namesCntp = max_zones;
- if (info != *infop) {
- vm_size_t used;
- vm_map_copy_t copy;
+ assert(submap_min == map_range->max_address);
+
+ zone_metadata_init();
- used = max_zones * sizeof *info;
+#if VM_MAX_TAG_ZONES
+ if (zone_tagging_on) {
+ zone_tagging_init(zone_map_size);
+ }
+#endif
+#if CONFIG_GZALLOC
+ gzalloc_init(zone_map_size);
+#endif
- if (used != info_size)
- bzero((char *) (info_addr + used), info_size - used);
+ zone_create_flags_t kma_flags = ZC_NOCACHING |
+ ZC_NOGC | ZC_NOENCRYPT | ZC_NOGZALLOC | ZC_NOCALLOUT |
+ ZC_KASAN_NOQUARANTINE | ZC_KASAN_NOREDZONE;
- kr = vm_map_copyin(ipc_kernel_map, (vm_map_address_t)info_addr,
- (vm_map_size_t)info_size, TRUE, ©);
- assert(kr == KERN_SUCCESS);
+ (void)zone_create_ext("vm.permanent", 1, kma_flags,
+ ZONE_ID_PERMANENT, ^(zone_t z){
+ z->z_permanent = true;
+ z->z_elem_size = 1;
+#if defined(__LP64__)
+ z->z_submap_idx = Z_SUBMAP_IDX_VA_RESTRICTED;
+#endif
+ });
+ (void)zone_create_ext("vm.permanent.percpu", 1, kma_flags | ZC_PERCPU,
+ ZONE_ID_PERCPU_PERMANENT, ^(zone_t z){
+ z->z_permanent = true;
+ z->z_elem_size = 1;
+#if defined(__LP64__)
+ z->z_submap_idx = Z_SUBMAP_IDX_VA_RESTRICTED;
+#endif
+ });
- *infop = (zone_info_t *) copy;
+ /*
+ * Now migrate the startup statistics into their final storage.
+ */
+ int cpu = cpu_number();
+ zone_index_foreach(idx) {
+ zone_t tz = &zone_array[idx];
+
+ if (tz->z_stats == __zpcpu_mangle_for_boot(&zone_stats_startup[idx])) {
+ zone_stats_t zs = zalloc_percpu_permanent_type(struct zone_stats);
+
+ *zpercpu_get_cpu(zs, cpu) = *zpercpu_get_cpu(tz->z_stats, cpu);
+ tz->z_stats = zs;
+#if ZONE_ENABLE_LOGGING
+ if (tz->zone_logging && !tz->zlog_btlog) {
+ zone_enable_logging(tz);
+ }
+#endif /* ZONE_ENABLE_LOGGING */
+ }
}
- *infoCntp = max_zones;
- return KERN_SUCCESS;
+#if CONFIG_ZLEAKS
+ /*
+ * Initialize the zone leak monitor
+ */
+ zleak_init(zone_map_size);
+#endif /* CONFIG_ZLEAKS */
+
+#if VM_MAX_TAG_ZONES
+ if (zone_tagging_on) {
+ vm_allocation_zones_init();
+ }
+#endif
}
+STARTUP(ZALLOC, STARTUP_RANK_FIRST, zone_init);
-#if MACH_KDB
-#include <ddb/db_command.h>
-#include <ddb/db_output.h>
-#include <kern/kern_print.h>
+__startup_func
+static void
+zone_cache_bootstrap(void)
+{
+ zone_t magzone;
+
+ magzone = zone_create("zcc_magazine_zone", sizeof(struct zone_magazine) +
+ zc_mag_size() * sizeof(zone_element_t),
+ ZC_NOGZALLOC | ZC_KASAN_NOREDZONE | ZC_KASAN_NOQUARANTINE |
+ ZC_SEQUESTER | ZC_CACHING | ZC_ZFREE_CLEARMEM);
+ magzone->z_elems_rsv = (uint16_t)(2 * zpercpu_count());
-const char *zone_labels =
-"ENTRY COUNT TOT_SZ MAX_SZ ELT_SZ ALLOC_SZ NAME";
+ os_atomic_store(&zc_magazine_zone, magzone, compiler_acq_rel);
-/* Forwards */
-void db_print_zone(
- zone_t addr);
+ /*
+ * Now that we are initialized, we can enable zone caching for zones that
+ * were made before zcache_bootstrap() was called.
+ *
+ * The system is still single threaded so we don't need to take the lock.
+ */
+ zone_index_foreach(i) {
+ zone_t z = &zone_array[i];
+ if (z->z_pcpu_cache) {
+ z->z_pcpu_cache = NULL;
+ zone_enable_caching(z);
+ }
+ }
+}
+STARTUP(ZALLOC, STARTUP_RANK_FOURTH, zone_cache_bootstrap);
-#if ZONE_DEBUG
-void db_zone_check_active(
- zone_t zone);
-void db_zone_print_active(
- zone_t zone);
-#endif /* ZONE_DEBUG */
-void db_zone_print_free(
- zone_t zone);
void
-db_print_zone(
- zone_t addr)
+zalloc_first_proc_made(void)
{
- struct zone zcopy;
-
- zcopy = *addr;
-
- db_printf("%8x %8x %8x %8x %6x %8x %s ",
- addr, zcopy.count, zcopy.cur_size,
- zcopy.max_size, zcopy.elem_size,
- zcopy.alloc_size, zcopy.zone_name);
- if (zcopy.exhaustible)
- db_printf("H");
- if (zcopy.collectable)
- db_printf("C");
- if (zcopy.expandable)
- db_printf("X");
- db_printf("\n");
+ zone_caching_disabled = 0;
}
-/*ARGSUSED*/
-void
-db_show_one_zone(
- db_expr_t addr,
- int have_addr,
- __unused db_expr_t count,
- __unused char * modif)
+__startup_func
+vm_offset_t
+zone_foreign_mem_init(vm_size_t size)
{
- struct zone *z = (zone_t)((char *)0 + addr);
+ vm_offset_t mem;
- if (z == ZONE_NULL || !have_addr){
- db_error("No Zone\n");
- /*NOTREACHED*/
+ if (atop(size) > ZONE_FOREIGN_META_INLINE_COUNT) {
+ panic("ZONE_FOREIGN_META_INLINE_COUNT has become too small: "
+ "%d > %d", (int)atop(size), ZONE_FOREIGN_META_INLINE_COUNT);
}
- db_printf("%s\n", zone_labels);
- db_print_zone(z);
+ mem = (vm_offset_t)pmap_steal_memory(size);
+
+ zone_info.zi_meta_base = zone_foreign_meta_array_startup -
+ zone_pva_from_addr(mem).packed_address;
+ zone_info.zi_map_range[ZONE_ADDR_FOREIGN].min_address = mem;
+ zone_info.zi_map_range[ZONE_ADDR_FOREIGN].max_address = mem + size;
+
+ zone_info.zi_bits_range = (struct zone_map_range){
+ .min_address = (vm_offset_t)zba_chunk_startup,
+ .max_address = (vm_offset_t)zba_chunk_startup +
+ sizeof(zba_chunk_startup),
+ };
+ zba_init_chunk(0);
+
+ return mem;
}
-/*ARGSUSED*/
-void
-db_show_all_zones(
- __unused db_expr_t addr,
- int have_addr,
- db_expr_t count,
- __unused char * modif)
+#endif /* !ZALLOC_TEST */
+#pragma mark - tests
+#if DEBUG || DEVELOPMENT
+
+/*
+ * Used for sysctl kern.run_zone_test which is not thread-safe. Ensure only one
+ * thread goes through at a time. Or we can end up with multiple test zones (if
+ * a second zinit() comes through before zdestroy()), which could lead us to
+ * run out of zones.
+ */
+static SIMPLE_LOCK_DECLARE(zone_test_lock, 0);
+static boolean_t zone_test_running = FALSE;
+static zone_t test_zone_ptr = NULL;
+
+static uintptr_t *
+zone_copy_allocations(zone_t z, uintptr_t *elems, zone_pva_t page_index)
{
- zone_t z;
- unsigned total = 0;
+ vm_offset_t elem_size = zone_elem_size(z);
+ vm_offset_t base;
+ struct zone_page_metadata *meta;
- /*
- * Don't risk hanging by unconditionally locking,
- * risk of incoherent data is small (zones aren't freed).
- */
- have_addr = simple_lock_try(&all_zones_lock);
- count = num_zones;
- z = first_zone;
- if (have_addr) {
- simple_unlock(&all_zones_lock);
- }
+ while (!zone_pva_is_null(page_index)) {
+ base = zone_pva_to_addr(page_index);
+ meta = zone_pva_to_meta(page_index);
- db_printf("%s\n", zone_labels);
- for ( ; count > 0; count--) {
- if (!z) {
- db_error("Mangled Zone List\n");
- /*NOTREACHED*/
- }
- db_print_zone(z);
- total += z->cur_size,
+ if (meta->zm_inline_bitmap) {
+ for (size_t i = 0; i < meta->zm_chunk_len; i++) {
+ uint32_t map = meta[i].zm_bitmap;
- have_addr = simple_lock_try(&all_zones_lock);
- z = z->next_zone;
- if (have_addr) {
- simple_unlock(&all_zones_lock);
+ for (; map; map &= map - 1) {
+ *elems++ = INSTANCE_PUT(base +
+ elem_size * __builtin_clz(map));
+ }
+ base += elem_size * 32;
+ }
+ } else {
+ uint32_t order = zba_bits_ref_order(meta->zm_bitmap);
+ bitmap_t *bits = zba_bits_ref_ptr(meta->zm_bitmap);
+ for (size_t i = 0; i < (1u << order); i++) {
+ uint64_t map = bits[i];
+
+ for (; map; map &= map - 1) {
+ *elems++ = INSTANCE_PUT(base +
+ elem_size * __builtin_clzll(map));
+ }
+ base += elem_size * 64;
+ }
}
+
+ page_index = meta->zm_page_next;
}
- db_printf("\nTotal %8x", total);
- db_printf("\n\nzone_gc() has reclaimed %d pages\n", zgc_stats.pgs_freed);
+ return elems;
}
-#if ZONE_DEBUG
-void
-db_zone_check_active(
- zone_t zone)
+kern_return_t
+zone_leaks(const char * zoneName, uint32_t nameLen, leak_site_proc proc, void * refCon)
{
- int count = 0;
- queue_t tmp_elem;
-
- if (!zone_debug_enabled(zone) || !zone_check)
- return;
- tmp_elem = queue_first(&zone->active_zones);
- while (count < zone->count) {
- count++;
- if (tmp_elem == 0) {
- printf("unexpected zero element, zone=0x%x, count=%d\n",
- zone, count);
- assert(FALSE);
- break;
- }
- if (queue_end(tmp_elem, &zone->active_zones)) {
- printf("unexpected queue_end, zone=0x%x, count=%d\n",
- zone, count);
- assert(FALSE);
+ uintptr_t zbt[MAX_ZTRACE_DEPTH];
+ zone_t zone = NULL;
+ uintptr_t * array;
+ uintptr_t * next;
+ uintptr_t element, bt;
+ uint32_t idx, count, found;
+ uint32_t btidx, btcount, nobtcount, btfound;
+ uint32_t elemSize;
+ size_t maxElems;
+ kern_return_t kr;
+
+ zone_foreach(z) {
+ if (!strncmp(zoneName, z->z_name, nameLen)) {
+ zone = z;
break;
}
- tmp_elem = queue_next(tmp_elem);
}
- if (!queue_end(tmp_elem, &zone->active_zones)) {
- printf("not at queue_end, zone=0x%x, tmp_elem=0x%x\n",
- zone, tmp_elem);
- assert(FALSE);
+ if (zone == NULL) {
+ return KERN_INVALID_NAME;
}
-}
-void
-db_zone_print_active(
- zone_t zone)
-{
- int count = 0;
- queue_t tmp_elem;
+ elemSize = (uint32_t)zone_elem_size(zone);
+ maxElems = (zone->z_elems_avail + 1) & ~1ul;
- if (!zone_debug_enabled(zone)) {
- printf("zone 0x%x debug not enabled\n", zone);
- return;
+ if ((ptoa(zone->z_percpu ? 1 : zone->z_chunk_pages) % elemSize) &&
+ !zone_leaks_scan_enable) {
+ return KERN_INVALID_CAPABILITY;
}
- if (!zone_check) {
- printf("zone_check FALSE\n");
- return;
+
+ kr = kmem_alloc_kobject(kernel_map, (vm_offset_t *) &array,
+ maxElems * sizeof(uintptr_t), VM_KERN_MEMORY_DIAG);
+ if (KERN_SUCCESS != kr) {
+ return kr;
}
- printf("zone 0x%x, active elements %d\n", zone, zone->count);
- printf("active list:\n");
- tmp_elem = queue_first(&zone->active_zones);
- while (count < zone->count) {
- printf(" 0x%x", tmp_elem);
- count++;
- if ((count % 6) == 0)
- printf("\n");
- if (tmp_elem == 0) {
- printf("\nunexpected zero element, count=%d\n", count);
- break;
- }
- if (queue_end(tmp_elem, &zone->active_zones)) {
- printf("\nunexpected queue_end, count=%d\n", count);
- break;
+ zone_lock(zone);
+
+ next = array;
+ next = zone_copy_allocations(zone, next, zone->z_pageq_partial);
+ next = zone_copy_allocations(zone, next, zone->z_pageq_full);
+ count = (uint32_t)(next - array);
+
+ zone_unlock(zone);
+
+ zone_leaks_scan(array, count, (uint32_t)zone_elem_size(zone), &found);
+ assert(found <= count);
+
+ for (idx = 0; idx < count; idx++) {
+ element = array[idx];
+ if (kInstanceFlagReferenced & element) {
+ continue;
}
- tmp_elem = queue_next(tmp_elem);
+ element = INSTANCE_PUT(element) & ~kInstanceFlags;
}
- if (!queue_end(tmp_elem, &zone->active_zones))
- printf("\nnot at queue_end, tmp_elem=0x%x\n", tmp_elem);
- else
- printf("\n");
-}
-#endif /* ZONE_DEBUG */
-void
-db_zone_print_free(
- zone_t zone)
-{
- int count = 0;
- int freecount;
- vm_offset_t elem;
-
- freecount = zone_free_count(zone);
- printf("zone 0x%x, free elements %d\n", zone, freecount);
- printf("free list:\n");
- elem = zone->free_elements;
- while (count < freecount) {
- printf(" 0x%x", elem);
- count++;
- if ((count % 6) == 0)
- printf("\n");
- if (elem == 0) {
- printf("\nunexpected zero element, count=%d\n", count);
- break;
+#if ZONE_ENABLE_LOGGING
+ if (zone->zlog_btlog && !corruption_debug_flag) {
+ // btlog_copy_backtraces_for_elements will set kInstanceFlagReferenced on elements it found
+ btlog_copy_backtraces_for_elements(zone->zlog_btlog, array, &count, elemSize, proc, refCon);
+ }
+#endif /* ZONE_ENABLE_LOGGING */
+
+ for (nobtcount = idx = 0; idx < count; idx++) {
+ element = array[idx];
+ if (!element) {
+ continue;
+ }
+ if (kInstanceFlagReferenced & element) {
+ continue;
+ }
+ element = INSTANCE_PUT(element) & ~kInstanceFlags;
+
+ // see if we can find any backtrace left in the element
+ btcount = (typeof(btcount))(zone_elem_size(zone) / sizeof(uintptr_t));
+ if (btcount >= MAX_ZTRACE_DEPTH) {
+ btcount = MAX_ZTRACE_DEPTH - 1;
+ }
+ for (btfound = btidx = 0; btidx < btcount; btidx++) {
+ bt = ((uintptr_t *)element)[btcount - 1 - btidx];
+ if (!VM_KERNEL_IS_SLID(bt)) {
+ break;
+ }
+ zbt[btfound++] = bt;
+ }
+ if (btfound) {
+ (*proc)(refCon, 1, elemSize, &zbt[0], btfound);
+ } else {
+ nobtcount++;
}
- elem = *((vm_offset_t *)elem);
}
- if (elem != 0)
- printf("\nnot at end of free list, elem=0x%x\n", elem);
- else
- printf("\n");
+ if (nobtcount) {
+ // fake backtrace when we found nothing
+ zbt[0] = (uintptr_t) &zalloc;
+ (*proc)(refCon, nobtcount, elemSize, &zbt[0], 1);
+ }
+
+ kmem_free(kernel_map, (vm_offset_t) array, maxElems * sizeof(uintptr_t));
+
+ return KERN_SUCCESS;
}
-#endif /* MACH_KDB */
+boolean_t
+run_zone_test(void)
+{
+ unsigned int i = 0, max_iter = 5;
+ void * test_ptr;
+ zone_t test_zone;
+ zone_t test_pcpu_zone;
+ kern_return_t kr;
+
+ simple_lock(&zone_test_lock, &zone_locks_grp);
+ if (!zone_test_running) {
+ zone_test_running = TRUE;
+ } else {
+ simple_unlock(&zone_test_lock);
+ printf("run_zone_test: Test already running.\n");
+ return FALSE;
+ }
+ simple_unlock(&zone_test_lock);
+ printf("run_zone_test: Testing zinit(), zalloc(), zfree() and zdestroy() on zone \"test_zone_sysctl\"\n");
-#if ZONE_DEBUG
+ /* zinit() and zdestroy() a zone with the same name a bunch of times, verify that we get back the same zone each time */
+ do {
+ test_zone = zinit(sizeof(uint64_t), 100 * sizeof(uint64_t), sizeof(uint64_t), "test_zone_sysctl");
+ if (test_zone == NULL) {
+ printf("run_zone_test: zinit() failed\n");
+ return FALSE;
+ }
-/* should we care about locks here ? */
+#if KASAN_ZALLOC
+ if (test_zone_ptr == NULL && test_zone->z_elems_free != 0) {
+#else
+ if (test_zone->z_elems_free != 0) {
+#endif
+ printf("run_zone_test: free count is not zero\n");
+ return FALSE;
+ }
-#if MACH_KDB
-void *
-next_element(
- zone_t z,
- void *prev)
-{
- char *elt = (char *)prev;
+ if (test_zone_ptr == NULL) {
+ /* Stash the zone pointer returned on the fist zinit */
+ printf("run_zone_test: zone created for the first time\n");
+ test_zone_ptr = test_zone;
+ } else if (test_zone != test_zone_ptr) {
+ printf("run_zone_test: old zone pointer and new zone pointer don't match\n");
+ return FALSE;
+ }
- if (!zone_debug_enabled(z))
- return(0);
- elt -= ZONE_DEBUG_OFFSET;
- elt = (char *) queue_next((queue_t) elt);
- if ((queue_t) elt == &z->active_zones)
- return(0);
- elt += ZONE_DEBUG_OFFSET;
- return(elt);
-}
+ test_ptr = zalloc(test_zone);
+ if (test_ptr == NULL) {
+ printf("run_zone_test: zalloc() failed\n");
+ return FALSE;
+ }
+ zfree(test_zone, test_ptr);
+
+ zdestroy(test_zone);
+ i++;
+
+ printf("run_zone_test: Iteration %d successful\n", i);
+ } while (i < max_iter);
+
+ /* test Z_VA_SEQUESTER */
+ if (zsecurity_options & ZSECURITY_OPTIONS_SEQUESTER) {
+ int idx, num_allocs = 8;
+ vm_size_t elem_size = 2 * PAGE_SIZE / num_allocs;
+ void *allocs[num_allocs];
+ void **allocs_pcpu;
+ vm_offset_t phys_pages = os_atomic_load(&zones_phys_page_mapped_count, relaxed);
+
+ test_zone = zone_create("test_zone_sysctl", elem_size,
+ ZC_DESTRUCTIBLE | ZC_SEQUESTER);
+ assert(test_zone);
+
+ test_pcpu_zone = zone_create("test_zone_sysctl.pcpu", sizeof(uint64_t),
+ ZC_DESTRUCTIBLE | ZC_SEQUESTER | ZC_PERCPU);
+ assert(test_pcpu_zone);
+
+ for (idx = 0; idx < num_allocs; idx++) {
+ allocs[idx] = zalloc(test_zone);
+ assert(NULL != allocs[idx]);
+ printf("alloc[%d] %p\n", idx, allocs[idx]);
+ }
+ for (idx = 0; idx < num_allocs; idx++) {
+ zfree(test_zone, allocs[idx]);
+ }
+ assert(!zone_pva_is_null(test_zone->z_pageq_empty));
-void *
-first_element(
- zone_t z)
-{
- char *elt;
+ kr = kernel_memory_allocate(kernel_map,
+ (vm_address_t *)&allocs_pcpu, PAGE_SIZE,
+ 0, KMA_ZERO | KMA_KOBJECT, VM_KERN_MEMORY_DIAG);
+ assert(kr == KERN_SUCCESS);
- if (!zone_debug_enabled(z))
- return(0);
- if (queue_empty(&z->active_zones))
- return(0);
- elt = (char *)queue_first(&z->active_zones);
- elt += ZONE_DEBUG_OFFSET;
- return(elt);
-}
+ for (idx = 0; idx < PAGE_SIZE / sizeof(uint64_t); idx++) {
+ allocs_pcpu[idx] = zalloc_percpu(test_pcpu_zone,
+ Z_WAITOK | Z_ZERO);
+ assert(NULL != allocs_pcpu[idx]);
+ }
+ for (idx = 0; idx < PAGE_SIZE / sizeof(uint64_t); idx++) {
+ zfree_percpu(test_pcpu_zone, allocs_pcpu[idx]);
+ }
+ assert(!zone_pva_is_null(test_pcpu_zone->z_pageq_empty));
+
+ printf("vm_page_wire_count %d, vm_page_free_count %d, p to v %ld%%\n",
+ vm_page_wire_count, vm_page_free_count,
+ 100L * phys_pages / zone_phys_mapped_max_pages);
+ zone_gc(ZONE_GC_DRAIN);
+ printf("vm_page_wire_count %d, vm_page_free_count %d, p to v %ld%%\n",
+ vm_page_wire_count, vm_page_free_count,
+ 100L * phys_pages / zone_phys_mapped_max_pages);
+
+ unsigned int allva = 0;
+
+ zone_foreach(z) {
+ zone_lock(z);
+ allva += z->z_wired_cur;
+ if (zone_pva_is_null(z->z_pageq_va)) {
+ zone_unlock(z);
+ continue;
+ }
+ unsigned count = 0;
+ uint64_t size;
+ zone_pva_t pg = z->z_pageq_va;
+ struct zone_page_metadata *page_meta;
+ while (pg.packed_address) {
+ page_meta = zone_pva_to_meta(pg);
+ count += z->z_percpu ? 1 : z->z_chunk_pages;
+ if (page_meta->zm_chunk_len == ZM_SECONDARY_PAGE) {
+ count -= page_meta->zm_page_index;
+ }
+ pg = page_meta->zm_page_next;
+ }
+ assert(z->z_wired_cur + count == z->z_va_cur);
+ size = zone_size_wired(z);
+ if (!size) {
+ size = 1;
+ }
+ printf("%s%s: seq %d, res %d, %qd %%\n",
+ zone_heap_name(z), z->z_name, z->z_va_cur - z->z_wired_cur,
+ z->z_wired_cur, zone_size_allocated(z) * 100ULL / size);
+ zone_unlock(z);
+ }
-/*
- * Second arg controls how many zone elements are printed:
- * 0 => none
- * n, n < 0 => all
- * n, n > 0 => last n on active list
- */
-int
-zone_count(
- zone_t z,
- int tail)
-{
- void *elt;
- int count = 0;
- boolean_t print = (tail != 0);
+ printf("total va: %d\n", allva);
+
+ assert(zone_pva_is_null(test_zone->z_pageq_empty));
+ assert(zone_pva_is_null(test_zone->z_pageq_partial));
+ assert(!zone_pva_is_null(test_zone->z_pageq_va));
+ assert(zone_pva_is_null(test_pcpu_zone->z_pageq_empty));
+ assert(zone_pva_is_null(test_pcpu_zone->z_pageq_partial));
+ assert(!zone_pva_is_null(test_pcpu_zone->z_pageq_va));
+
+ for (idx = 0; idx < num_allocs; idx++) {
+ assert(0 == pmap_find_phys(kernel_pmap, (addr64_t)(uintptr_t) allocs[idx]));
+ }
+
+ /* make sure the zone is still usable after a GC */
+
+ for (idx = 0; idx < num_allocs; idx++) {
+ allocs[idx] = zalloc(test_zone);
+ assert(allocs[idx]);
+ printf("alloc[%d] %p\n", idx, allocs[idx]);
+ }
+ assert(zone_pva_is_null(test_zone->z_pageq_va));
+ assert(test_zone->z_wired_cur == test_zone->z_va_cur);
+ for (idx = 0; idx < num_allocs; idx++) {
+ zfree(test_zone, allocs[idx]);
+ }
+
+ for (idx = 0; idx < PAGE_SIZE / sizeof(uint64_t); idx++) {
+ allocs_pcpu[idx] = zalloc_percpu(test_pcpu_zone,
+ Z_WAITOK | Z_ZERO);
+ assert(NULL != allocs_pcpu[idx]);
+ }
+ for (idx = 0; idx < PAGE_SIZE / sizeof(uint64_t); idx++) {
+ zfree_percpu(test_pcpu_zone, allocs_pcpu[idx]);
+ }
- if (tail < 0)
- tail = z->count;
- if (z->count < tail)
- tail = 0;
- tail = z->count - tail;
- for (elt = first_element(z); elt; elt = next_element(z, elt)) {
- if (print && tail <= count)
- db_printf("%8x\n", elt);
- count++;
+ assert(!zone_pva_is_null(test_pcpu_zone->z_pageq_empty));
+ assert(zone_pva_is_null(test_pcpu_zone->z_pageq_va));
+
+ kmem_free(kernel_map, (vm_address_t)allocs_pcpu, PAGE_SIZE);
+
+ zdestroy(test_zone);
+ zdestroy(test_pcpu_zone);
+ } else {
+ printf("run_zone_test: skipping sequester test (not enabled)\n");
}
- assert(count == z->count);
- return(count);
+
+ printf("run_zone_test: Test passed\n");
+
+ simple_lock(&zone_test_lock, &zone_locks_grp);
+ zone_test_running = FALSE;
+ simple_unlock(&zone_test_lock);
+
+ return TRUE;
}
-#endif /* MACH_KDB */
-#define zone_in_use(z) ( z->count || z->free_elements )
+/*
+ * Routines to test that zone garbage collection and zone replenish threads
+ * running at the same time don't cause problems.
+ */
void
-zone_debug_enable(
- zone_t z)
+zone_gc_replenish_test(void)
{
- if (zone_debug_enabled(z) || zone_in_use(z) ||
- z->alloc_size < (z->elem_size + ZONE_DEBUG_OFFSET))
- return;
- queue_init(&z->active_zones);
- z->elem_size += ZONE_DEBUG_OFFSET;
+ zone_gc(ZONE_GC_DRAIN);
}
+
void
-zone_debug_disable(
- zone_t z)
+zone_alloc_replenish_test(void)
{
- if (!zone_debug_enabled(z) || zone_in_use(z))
+ zone_t z = NULL;
+ struct data { struct data *next; } *node, *list = NULL;
+
+ /*
+ * Find a zone that has a replenish thread
+ */
+ zone_index_foreach(i) {
+ z = &zone_array[i];
+ if (z->z_replenishes && zone_elem_size(z) >= sizeof(struct data)) {
+ z = &zone_array[i];
+ break;
+ }
+ }
+ if (z == NULL) {
+ printf("Couldn't find a replenish zone\n");
return;
- z->elem_size -= ZONE_DEBUG_OFFSET;
- z->active_zones.next = z->active_zones.prev = 0;
+ }
+
+ for (uint32_t i = 0; i < 2000; ++i) { /* something big enough to go past replenishment */
+ node = zalloc(z);
+ node->next = list;
+ list = node;
+ }
+
+ /*
+ * release the memory we allocated
+ */
+ while (list != NULL) {
+ node = list;
+ list = list->next;
+ zfree(z, node);
+ }
}
-#endif /* ZONE_DEBUG */
+
+#endif /* DEBUG || DEVELOPMENT */
projects / apple / xnu.git / blobdiff