/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_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 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.
*
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * 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.
+ * 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_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* @OSF_COPYRIGHT@
#ifndef _VM_VM_OBJECT_H_
#define _VM_VM_OBJECT_H_
+#include <debug.h>
+#include <mach_assert.h>
#include <mach_pagemap.h>
#include <task_swapper.h>
#include <mach/memory_object_types.h>
#include <mach/port.h>
#include <mach/vm_prot.h>
+#include <mach/vm_param.h>
#include <mach/machine/vm_types.h>
#include <kern/queue.h>
-#include <kern/lock.h>
+#include <kern/locks.h>
#include <kern/assert.h>
+#include <kern/misc_protos.h>
#include <kern/macro_help.h>
#include <ipc/ipc_types.h>
#include <vm/pmap.h>
-#include <kern/misc_protos.h>
-#if MACH_PAGEMAP
#include <vm/vm_external.h>
-#endif /* MACH_PAGEMAP */
-typedef struct ipc_port * pager_request_t;
-#define PAGER_REQUEST_NULL ((pager_request_t) 0)
+#include <vm/vm_options.h>
+#include <vm/vm_page.h>
+
+#if VM_OBJECT_TRACKING
+#include <libkern/OSDebug.h>
+#include <kern/btlog.h>
+extern void vm_object_tracking_init(void);
+extern boolean_t vm_object_tracking_inited;
+extern btlog_t *vm_object_tracking_btlog;
+#define VM_OBJECT_TRACKING_NUM_RECORDS 50000
+#define VM_OBJECT_TRACKING_BTDEPTH 7
+#define VM_OBJECT_TRACKING_OP_CREATED 1
+#define VM_OBJECT_TRACKING_OP_MODIFIED 2
+#define VM_OBJECT_TRACKING_OP_TRUESHARE 3
+#endif /* VM_OBJECT_TRACKING */
+
+struct vm_page;
/*
* Types defined:
*
* vm_object_t Virtual memory object.
- *
- * We use "struct ipc_port *" instead of "ipc_port_t"
- * to avoid include file circularities.
+ * vm_object_fault_info_t Used to determine cluster size.
*/
-typedef unsigned long long vm_object_size_t;
+struct vm_object_fault_info {
+ int interruptible;
+ uint32_t user_tag;
+ vm_size_t cluster_size;
+ vm_behavior_t behavior;
+ vm_map_offset_t lo_offset;
+ vm_map_offset_t hi_offset;
+ unsigned int
+ /* boolean_t */ no_cache:1,
+ /* boolean_t */ stealth:1,
+ /* boolean_t */ io_sync:1,
+ /* boolean_t */ cs_bypass:1,
+ /* boolean_t */ pmap_cs_associated:1,
+ /* boolean_t */ mark_zf_absent:1,
+ /* boolean_t */ batch_pmap_op:1,
+ __vm_object_fault_info_unused_bits:25;
+ int pmap_options;
+};
-struct vm_object {
- queue_head_t memq; /* Resident memory */
- decl_mutex_data(, Lock) /* Synchronization */
+#define vo_size vo_un1.vou_size
+#define vo_cache_pages_to_scan vo_un1.vou_cache_pages_to_scan
+#define vo_shadow_offset vo_un2.vou_shadow_offset
+#define vo_cache_ts vo_un2.vou_cache_ts
+#define vo_owner vo_un2.vou_owner
- vm_object_size_t size; /* Object size (only valid
- * if internal)
- */
- vm_object_size_t frozen_size; /* How much has been marked
- * copy-on-write (only
- * valid if copy_symmetric)
- */
+struct vm_object {
+ /*
+ * on 64 bit systems we pack the pointers hung off the memq.
+ * those pointers have to be able to point back to the memq.
+ * the packed pointers are required to be on a 64 byte boundary
+ * which means 2 things for the vm_object... (1) the memq
+ * struct has to be the first element of the structure so that
+ * we can control it's alignment... (2) the vm_object must be
+ * aligned on a 64 byte boundary... for static vm_object's
+ * this is accomplished via the 'aligned' attribute... for
+ * vm_object's in the zone pool, this is accomplished by
+ * rounding the size of the vm_object element to the nearest
+ * 64 byte size before creating the zone.
+ */
+ vm_page_queue_head_t memq; /* Resident memory - must be first */
+ lck_rw_t Lock; /* Synchronization */
+
+#if DEVELOPMENT || DEBUG
+ thread_t Lock_owner;
+#endif
+ union {
+ vm_object_size_t vou_size; /* Object size (only valid if internal) */
+ int vou_cache_pages_to_scan; /* pages yet to be visited in an
+ * external object in cache
+ */
+ } vo_un1;
+
+ struct vm_page *memq_hint;
int ref_count; /* Number of references */
-#if TASK_SWAPPER
- int res_count; /* Residency references (swap)*/
-#endif /* TASK_SWAPPER */
unsigned int resident_page_count;
/* number of resident pages */
+ unsigned int wired_page_count; /* number of wired pages
+ use VM_OBJECT_WIRED_PAGE_UPDATE macros to update */
+ unsigned int reusable_page_count;
struct vm_object *copy; /* Object that should receive
* a copy of my changed pages,
* copy_call.
*/
struct vm_object *shadow; /* My shadow */
- vm_object_offset_t shadow_offset; /* Offset into shadow */
- struct ipc_port *pager; /* Where to get data */
+ union {
+ vm_object_offset_t vou_shadow_offset; /* Offset into shadow */
+ clock_sec_t vou_cache_ts; /* age of an external object
+ * present in cache
+ */
+ task_t vou_owner; /* If the object is purgeable
+ * or has a "ledger_tag", this
+ * is the task that owns it.
+ */
+ } vo_un2;
+
+ memory_object_t pager; /* Where to get data */
vm_object_offset_t paging_offset; /* Offset into memory object */
- pager_request_t pager_request; /* Where data comes back */
+ memory_object_control_t pager_control; /* Where data comes back */
memory_object_copy_strategy_t
copy_strategy; /* How to handle data copy */
- unsigned int absent_count; /* The number of pages that
- * have been requested but
- * not filled. That is, the
- * number of pages for which
- * the "absent" attribute is
- * asserted.
- */
-
- unsigned int paging_in_progress;
+#if __LP64__
+ /*
+ * Some user processes (mostly VirtualMachine software) take a large
+ * number of UPLs (via IOMemoryDescriptors) to wire pages in large
+ * VM objects and overflow the 16-bit "activity_in_progress" counter.
+ * Since we never enforced any limit there, let's give them 32 bits
+ * for backwards compatibility's sake.
+ */
+ unsigned int paging_in_progress:16,
+ __object1_unused_bits:16;
+ unsigned int activity_in_progress;
+#else /* __LP64__ */
+ /*
+ * On 32-bit platforms, enlarging "activity_in_progress" would increase
+ * the size of "struct vm_object". Since we don't know of any actual
+ * overflow of these counters on these platforms, let's keep the
+ * counters as 16-bit integers.
+ */
+ unsigned short paging_in_progress;
+ unsigned short activity_in_progress;
+#endif /* __LP64__ */
/* The memory object ports are
* being used (e.g., for pagein
* or pageout) -- don't change
* don't collapse, destroy or
* terminate)
*/
+
unsigned int
/* boolean_t array */ all_wanted:11, /* Bit array of "want to be
* awakened" notations. See
* therefore, managed by the
* default memory manger)
*/
- /* boolean_t */ temporary:1, /* Permanent objects may be
- * changed externally by the
- * memory manager, and changes
- * made in memory must be
- * reflected back to the memory
- * manager. Temporary objects
- * lack both of these
- * characteristics.
- */
/* boolean_t */ private:1, /* magic device_pager object,
* holds private pages only */
/* boolean_t */ pageout:1, /* pageout object. contains
* a real memory object. */
/* boolean_t */ alive:1, /* Not yet terminated */
- /* boolean_t */ lock_in_progress:1,
- /* Is a multi-page lock
- * request in progress?
- */
- /* boolean_t */ lock_restart:1,
- /* Should lock request in
- * progress restart search?
+ /* boolean_t */ purgable:2, /* Purgable state. See
+ * VM_PURGABLE_*
*/
+ /* boolean_t */ purgeable_only_by_kernel:1,
+ /* boolean_t */ purgeable_when_ripe:1, /* Purgeable when a token
+ * becomes ripe.
+ */
/* boolean_t */ shadowed:1, /* Shadow may exist */
- /* boolean_t */ silent_overwrite:1,
- /* Allow full page overwrite
- * without data_request if
- * page is absent */
- /* boolean_t */ advisory_pageout:1,
- /* Instead of sending page
- * via OOL, just notify
- * pager that the kernel
- * wants to discard it, page
- * remains in object */
/* boolean_t */ true_share:1,
/* This object is mapped
* in more than one place
* an error rather than a
* zero filled page.
*/
- /* boolean_t */ phys_contiguous:1;
+ /* boolean_t */ phys_contiguous:1,
/* Memory is wired and
* guaranteed physically
* contiguous. However
* memory rules w.r.t pmap
* access bits.
*/
-
-
+ /* boolean_t */ nophyscache:1,
+ /* When mapped at the
+ * pmap level, don't allow
+ * primary caching. (for
+ * I/O)
+ */
+ /* boolean_t */ _object5_unused_bits:1;
queue_chain_t cached_list; /* Attachment point for the
* list of objects cached as a
* result of their can_persist
* value
*/
-
- queue_head_t msr_q; /* memory object synchronise
- request queue */
-
+ /*
+ * the following fields are not protected by any locks
+ * they are updated via atomic compare and swap
+ */
vm_object_offset_t last_alloc; /* last allocation offset */
- vm_size_t cluster_size; /* size of paging cluster */
-#if MACH_PAGEMAP
- vm_external_map_t existence_map; /* bitmap of pages written to
- * backing storage */
-#endif /* MACH_PAGEMAP */
-#if MACH_ASSERT
- struct vm_object *paging_object; /* object which pages to be
- * swapped out are temporary
- * put in current object
- */
+ int sequential; /* sequential access size */
+
+ uint32_t pages_created;
+ uint32_t pages_used;
+ vm_offset_t cow_hint; /* last page present in */
+ /* shadow but not in object */
+ /* hold object lock when altering */
+ unsigned int
+ wimg_bits:8, /* cache WIMG bits */
+ code_signed:1, /* pages are signed and should be
+ validated; the signatures are stored
+ with the pager */
+ transposed:1, /* object was transposed with another */
+ mapping_in_progress:1, /* pager being mapped/unmapped */
+ phantom_isssd:1,
+ volatile_empty:1,
+ volatile_fault:1,
+ all_reusable:1,
+ blocked_access:1,
+ set_cache_attr:1,
+ object_is_shared_cache:1,
+ purgeable_queue_type:2,
+ purgeable_queue_group:3,
+ io_tracking:1,
+ no_tag_update:1, /* */
+#if CONFIG_SECLUDED_MEMORY
+ eligible_for_secluded:1,
+ can_grab_secluded:1,
+#else /* CONFIG_SECLUDED_MEMORY */
+ __object3_unused_bits:2,
+#endif /* CONFIG_SECLUDED_MEMORY */
+#if VM_OBJECT_ACCESS_TRACKING
+ access_tracking:1,
+#else /* VM_OBJECT_ACCESS_TRACKING */
+ __unused_access_tracking:1,
+#endif /* VM_OBJECT_ACCESS_TRACKING */
+ vo_ledger_tag:2,
+ __object2_unused_bits:2; /* for expansion */
+
+#if VM_OBJECT_ACCESS_TRACKING
+ uint32_t access_tracking_reads;
+ uint32_t access_tracking_writes;
+#endif /* VM_OBJECT_ACCESS_TRACKING */
+
+ uint8_t scan_collisions;
+ vm_tag_t wire_tag;
+ uint8_t __object4_unused_bits[2];
+
+#if CONFIG_PHANTOM_CACHE
+ uint32_t phantom_object_id;
#endif
-#ifdef UBC_DEBUG
+#if CONFIG_IOSCHED || UPL_DEBUG
queue_head_t uplq; /* List of outstanding upls */
-#endif /* UBC_DEBUG */
+#endif
+
+#ifdef VM_PIP_DEBUG
+/*
+ * Keep track of the stack traces for the first holders
+ * of a "paging_in_progress" reference for this VM object.
+ */
+#define VM_PIP_DEBUG_STACK_FRAMES 25 /* depth of each stack trace */
+#define VM_PIP_DEBUG_MAX_REFS 10 /* track that many references */
+ struct __pip_backtrace {
+ void *pip_retaddr[VM_PIP_DEBUG_STACK_FRAMES];
+ } pip_holders[VM_PIP_DEBUG_MAX_REFS];
+#endif /* VM_PIP_DEBUG */
+
+ queue_chain_t objq; /* object queue - currently used for purgable queues */
+ queue_chain_t task_objq; /* objects owned by task - protected by task lock */
+
+#if !VM_TAG_ACTIVE_UPDATE
+ queue_chain_t wired_objq;
+#endif /* !VM_TAG_ACTIVE_UPDATE */
+
+#if DEBUG
+ void *purgeable_owner_bt[16];
+ task_t vo_purgeable_volatilizer; /* who made it volatile? */
+ void *purgeable_volatilizer_bt[16];
+#endif /* DEBUG */
};
+/* values for object->vo_ledger_tag */
+#define VM_OBJECT_LEDGER_TAG_NONE 0
+#define VM_OBJECT_LEDGER_TAG_NETWORK 1
+#define VM_OBJECT_LEDGER_TAG_MEDIA 2
+#define VM_OBJECT_LEDGER_TAG_RESERVED 3
+
+#define VM_OBJECT_PURGEABLE_FAULT_ERROR(object) \
+ ((object)->volatile_fault && \
+ ((object)->purgable == VM_PURGABLE_VOLATILE || \
+ (object)->purgable == VM_PURGABLE_EMPTY))
+
+#if VM_OBJECT_ACCESS_TRACKING
+extern uint64_t vm_object_access_tracking_reads;
+extern uint64_t vm_object_access_tracking_writes;
+extern void vm_object_access_tracking(vm_object_t object,
+ int *access_tracking,
+ uint32_t *access_tracking_reads,
+ uint32_t *acess_tracking_writes);
+#endif /* VM_OBJECT_ACCESS_TRACKING */
+
extern
vm_object_t kernel_object; /* the single kernel object */
-int vm_object_absent_max; /* maximum number of absent pages
+extern
+vm_object_t compressor_object; /* the single compressor object */
+
+extern
+unsigned int vm_object_absent_max; /* maximum number of absent pages
at a time for each object */
# define VM_MSYNC_INITIALIZED 0
# define VM_MSYNC_SYNCHRONIZING 1
# define VM_MSYNC_DONE 2
-struct msync_req {
- queue_chain_t msr_q; /* object request queue */
- queue_chain_t req_q; /* vm_msync request queue */
- unsigned int flag;
- vm_object_offset_t offset;
- vm_object_size_t length;
- vm_object_t object; /* back pointer */
- decl_mutex_data(, msync_req_lock) /* Lock for this structure */
-};
-typedef struct msync_req *msync_req_t;
-#define MSYNC_REQ_NULL ((msync_req_t) 0)
+extern lck_grp_t vm_map_lck_grp;
+extern lck_attr_t vm_map_lck_attr;
+
+#ifndef VM_TAG_ACTIVE_UPDATE
+#error VM_TAG_ACTIVE_UPDATE
+#endif
+
+#if VM_TAG_ACTIVE_UPDATE
+#define VM_OBJECT_WIRED_ENQUEUE(object) panic("VM_OBJECT_WIRED_ENQUEUE")
+#define VM_OBJECT_WIRED_DEQUEUE(object) panic("VM_OBJECT_WIRED_DEQUEUE")
+#else /* VM_TAG_ACTIVE_UPDATE */
+#define VM_OBJECT_WIRED_ENQUEUE(object) \
+ MACRO_BEGIN \
+ lck_spin_lock(&vm_objects_wired_lock); \
+ assert(!(object)->wired_objq.next); \
+ assert(!(object)->wired_objq.prev); \
+ queue_enter(&vm_objects_wired, (object), \
+ vm_object_t, wired_objq); \
+ lck_spin_unlock(&vm_objects_wired_lock); \
+ MACRO_END
+#define VM_OBJECT_WIRED_DEQUEUE(object) \
+ MACRO_BEGIN \
+ if ((object)->wired_objq.next) { \
+ lck_spin_lock(&vm_objects_wired_lock); \
+ queue_remove(&vm_objects_wired, (object), \
+ vm_object_t, wired_objq); \
+ lck_spin_unlock(&vm_objects_wired_lock); \
+ } \
+ MACRO_END
+#endif /* VM_TAG_ACTIVE_UPDATE */
+
+#define VM_OBJECT_WIRED(object, tag) \
+ MACRO_BEGIN \
+ assert(VM_KERN_MEMORY_NONE != (tag)); \
+ assert(VM_KERN_MEMORY_NONE == (object)->wire_tag); \
+ (object)->wire_tag = (tag); \
+ if (!VM_TAG_ACTIVE_UPDATE) { \
+ VM_OBJECT_WIRED_ENQUEUE((object)); \
+ } \
+ MACRO_END
+
+#define VM_OBJECT_UNWIRED(object) \
+ MACRO_BEGIN \
+ if (!VM_TAG_ACTIVE_UPDATE) { \
+ VM_OBJECT_WIRED_DEQUEUE((object)); \
+ } \
+ if (VM_KERN_MEMORY_NONE != (object)->wire_tag) { \
+ vm_tag_update_size((object)->wire_tag, -ptoa_64((object)->wired_page_count)); \
+ (object)->wire_tag = VM_KERN_MEMORY_NONE; \
+ } \
+ MACRO_END
+
+// These two macros start & end a C block
+#define VM_OBJECT_WIRED_PAGE_UPDATE_START(object) \
+ MACRO_BEGIN \
+ { \
+ int64_t __wireddelta = 0; vm_tag_t __waswired = (object)->wire_tag;
+
+#define VM_OBJECT_WIRED_PAGE_UPDATE_END(object, tag) \
+ if (__wireddelta) { \
+ boolean_t __overflow __assert_only = \
+ os_add_overflow((object)->wired_page_count, __wireddelta, \
+ &(object)->wired_page_count); \
+ assert(!__overflow); \
+ if (!(object)->pageout && !(object)->no_tag_update) { \
+ if (__wireddelta > 0) { \
+ assert (VM_KERN_MEMORY_NONE != (tag)); \
+ if (VM_KERN_MEMORY_NONE == __waswired) { \
+ VM_OBJECT_WIRED((object), (tag)); \
+ } \
+ vm_tag_update_size((object)->wire_tag, ptoa_64(__wireddelta)); \
+ } else if (VM_KERN_MEMORY_NONE != __waswired) { \
+ assert (VM_KERN_MEMORY_NONE != (object)->wire_tag); \
+ vm_tag_update_size((object)->wire_tag, ptoa_64(__wireddelta)); \
+ if (!(object)->wired_page_count) { \
+ VM_OBJECT_UNWIRED((object)); \
+ } \
+ } \
+ } \
+ } \
+ } \
+ MACRO_END
+
+#define VM_OBJECT_WIRED_PAGE_COUNT(object, delta) \
+ __wireddelta += delta; \
+
+#define VM_OBJECT_WIRED_PAGE_ADD(object, m) \
+ if (!(m)->vmp_private && !(m)->vmp_fictitious) __wireddelta++;
+
+#define VM_OBJECT_WIRED_PAGE_REMOVE(object, m) \
+ if (!(m)->vmp_private && !(m)->vmp_fictitious) __wireddelta--;
+
+
+
+#define OBJECT_LOCK_SHARED 0
+#define OBJECT_LOCK_EXCLUSIVE 1
+
+extern lck_grp_t vm_object_lck_grp;
+extern lck_grp_attr_t vm_object_lck_grp_attr;
+extern lck_attr_t vm_object_lck_attr;
+extern lck_attr_t kernel_object_lck_attr;
+extern lck_attr_t compressor_object_lck_attr;
+
+extern vm_object_t vm_pageout_scan_wants_object;
+
+extern void vm_object_lock(vm_object_t);
+extern boolean_t vm_object_lock_try(vm_object_t);
+extern boolean_t _vm_object_lock_try(vm_object_t);
+extern boolean_t vm_object_lock_avoid(vm_object_t);
+extern void vm_object_lock_shared(vm_object_t);
+extern boolean_t vm_object_lock_yield_shared(vm_object_t);
+extern boolean_t vm_object_lock_try_shared(vm_object_t);
+extern void vm_object_unlock(vm_object_t);
+extern boolean_t vm_object_lock_upgrade(vm_object_t);
/*
- * Macros to allocate and free msync_reqs
+ * Object locking macros
*/
-#define msync_req_alloc(msr) \
- MACRO_BEGIN \
- (msr) = (msync_req_t)kalloc(sizeof(struct msync_req)); \
- mutex_init(&(msr)->msync_req_lock, ETAP_VM_MSYNC); \
- msr->flag = VM_MSYNC_INITIALIZED; \
- MACRO_END
-#define msync_req_free(msr) \
- (kfree((vm_offset_t)(msr), sizeof(struct msync_req)))
+#define vm_object_lock_init(object) \
+ lck_rw_init(&(object)->Lock, &vm_object_lck_grp, \
+ (((object) == kernel_object || \
+ (object) == vm_submap_object) ? \
+ &kernel_object_lck_attr : \
+ (((object) == compressor_object) ? \
+ &compressor_object_lck_attr : \
+ &vm_object_lck_attr)))
+#define vm_object_lock_destroy(object) lck_rw_destroy(&(object)->Lock, &vm_object_lck_grp)
+
+#define vm_object_lock_try_scan(object) _vm_object_lock_try(object)
+
+/*
+ * CAUTION: the following vm_object_lock_assert_held*() macros merely
+ * check if anyone is holding the lock, but the holder may not necessarily
+ * be the caller...
+ */
+#if MACH_ASSERT || DEBUG
+#define vm_object_lock_assert_held(object) \
+ lck_rw_assert(&(object)->Lock, LCK_RW_ASSERT_HELD)
+#define vm_object_lock_assert_shared(object) \
+ lck_rw_assert(&(object)->Lock, LCK_RW_ASSERT_SHARED)
+#define vm_object_lock_assert_exclusive(object) \
+ lck_rw_assert(&(object)->Lock, LCK_RW_ASSERT_EXCLUSIVE)
+#define vm_object_lock_assert_notheld(object) \
+ lck_rw_assert(&(object)->Lock, LCK_RW_ASSERT_NOTHELD)
+#else /* MACH_ASSERT || DEBUG */
+#define vm_object_lock_assert_held(object)
+#define vm_object_lock_assert_shared(object)
+#define vm_object_lock_assert_exclusive(object)
+#define vm_object_lock_assert_notheld(object)
+#endif /* MACH_ASSERT || DEBUG */
-#define msr_lock(msr) mutex_lock(&(msr)->msync_req_lock)
-#define msr_unlock(msr) mutex_unlock(&(msr)->msync_req_lock)
/*
* Declare procedures that operate on VM objects.
*/
-extern void vm_object_bootstrap(void);
+__private_extern__ void vm_object_bootstrap(void);
+
+__private_extern__ void vm_object_init(void);
-extern void vm_object_init(void);
+__private_extern__ void vm_object_init_lck_grp(void);
-extern vm_object_t vm_object_allocate(
- vm_object_size_t size);
+__private_extern__ void vm_object_reaper_init(void);
-#if MACH_ASSERT
-extern void vm_object_reference(
+__private_extern__ vm_object_t vm_object_allocate(vm_object_size_t size);
+
+__private_extern__ void _vm_object_allocate(vm_object_size_t size,
+ vm_object_t object);
+
+#if TASK_SWAPPER
+
+__private_extern__ void vm_object_res_reference(
+ vm_object_t object);
+__private_extern__ void vm_object_res_deallocate(
+ vm_object_t object);
+#define VM_OBJ_RES_INCR(object) (object)->res_count++
+#define VM_OBJ_RES_DECR(object) (object)->res_count--
+
+#else /* TASK_SWAPPER */
+
+#define VM_OBJ_RES_INCR(object)
+#define VM_OBJ_RES_DECR(object)
+#define vm_object_res_reference(object)
+#define vm_object_res_deallocate(object)
+
+#endif /* TASK_SWAPPER */
+
+#define vm_object_reference_locked(object) \
+ MACRO_BEGIN \
+ vm_object_t RLObject = (object); \
+ vm_object_lock_assert_exclusive(object); \
+ assert((RLObject)->ref_count > 0); \
+ (RLObject)->ref_count++; \
+ assert((RLObject)->ref_count > 1); \
+ vm_object_res_reference(RLObject); \
+ MACRO_END
+
+
+#define vm_object_reference_shared(object) \
+ MACRO_BEGIN \
+ vm_object_t RLObject = (object); \
+ vm_object_lock_assert_shared(object); \
+ assert((RLObject)->ref_count > 0); \
+ OSAddAtomic(1, &(RLObject)->ref_count); \
+ assert((RLObject)->ref_count > 0); \
+ /* XXX we would need an atomic version of the following ... */ \
+ vm_object_res_reference(RLObject); \
+ MACRO_END
+
+
+__private_extern__ void vm_object_reference(
vm_object_t object);
-#else /* MACH_ASSERT */
+
+#if !MACH_ASSERT
+
#define vm_object_reference(object) \
MACRO_BEGIN \
- vm_object_t Object = (object); \
- if (Object) { \
- vm_object_lock(Object); \
- Object->ref_count++; \
- vm_object_res_reference(Object); \
- vm_object_unlock(Object); \
+ vm_object_t RObject = (object); \
+ if (RObject) { \
+ vm_object_lock_shared(RObject); \
+ vm_object_reference_shared(RObject); \
+ vm_object_unlock(RObject); \
} \
MACRO_END
+
#endif /* MACH_ASSERT */
-extern void vm_object_deallocate(
+__private_extern__ void vm_object_deallocate(
vm_object_t object);
-extern void vm_object_pmap_protect(
+__private_extern__ kern_return_t vm_object_release_name(
+ vm_object_t object,
+ int flags);
+
+__private_extern__ void vm_object_pmap_protect(
vm_object_t object,
vm_object_offset_t offset,
- vm_size_t size,
+ vm_object_size_t size,
pmap_t pmap,
- vm_offset_t pmap_start,
+ vm_map_offset_t pmap_start,
vm_prot_t prot);
-extern void vm_object_page_remove(
+__private_extern__ void vm_object_pmap_protect_options(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_object_size_t size,
+ pmap_t pmap,
+ vm_map_offset_t pmap_start,
+ vm_prot_t prot,
+ int options);
+
+__private_extern__ void vm_object_page_remove(
vm_object_t object,
vm_object_offset_t start,
vm_object_offset_t end);
-extern boolean_t vm_object_coalesce(
+__private_extern__ void vm_object_deactivate_pages(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_object_size_t size,
+ boolean_t kill_page,
+ boolean_t reusable_page,
+ struct pmap *pmap,
+ vm_map_offset_t pmap_offset);
+
+__private_extern__ void vm_object_reuse_pages(
+ vm_object_t object,
+ vm_object_offset_t start_offset,
+ vm_object_offset_t end_offset,
+ boolean_t allow_partial_reuse);
+
+__private_extern__ uint64_t vm_object_purge(
+ vm_object_t object,
+ int flags);
+
+__private_extern__ kern_return_t vm_object_purgable_control(
+ vm_object_t object,
+ vm_purgable_t control,
+ int *state);
+
+__private_extern__ kern_return_t vm_object_get_page_counts(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_object_size_t size,
+ unsigned int *resident_page_count,
+ unsigned int *dirty_page_count);
+
+__private_extern__ boolean_t vm_object_coalesce(
vm_object_t prev_object,
vm_object_t next_object,
vm_object_offset_t prev_offset,
vm_object_size_t prev_size,
vm_object_size_t next_size);
-extern boolean_t vm_object_shadow(
+__private_extern__ boolean_t vm_object_shadow(
vm_object_t *object,
vm_object_offset_t *offset,
vm_object_size_t length);
-extern void vm_object_collapse(
- vm_object_t object);
-
-extern vm_object_t vm_object_lookup(
- ipc_port_t port);
-
-extern ipc_port_t vm_object_name(
- vm_object_t object);
+__private_extern__ void vm_object_collapse(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ boolean_t can_bypass);
-extern boolean_t vm_object_copy_quickly(
+__private_extern__ boolean_t vm_object_copy_quickly(
vm_object_t *_object,
vm_object_offset_t src_offset,
vm_object_size_t size,
boolean_t *_src_needs_copy,
boolean_t *_dst_needs_copy);
-extern kern_return_t vm_object_copy_strategically(
+__private_extern__ kern_return_t vm_object_copy_strategically(
vm_object_t src_object,
vm_object_offset_t src_offset,
vm_object_size_t size,
vm_object_offset_t *dst_offset,
boolean_t *dst_needs_copy);
-extern kern_return_t vm_object_copy_slowly(
+__private_extern__ kern_return_t vm_object_copy_slowly(
vm_object_t src_object,
vm_object_offset_t src_offset,
vm_object_size_t size,
- int interruptible,
+ boolean_t interruptible,
vm_object_t *_result_object);
-extern void vm_object_pager_create(
- vm_object_t object);
+__private_extern__ vm_object_t vm_object_copy_delayed(
+ vm_object_t src_object,
+ vm_object_offset_t src_offset,
+ vm_object_size_t size,
+ boolean_t src_object_shared);
+
-extern void vm_object_destroy(
- ipc_port_t pager);
-extern void vm_object_pager_wakeup(
- ipc_port_t pager);
+__private_extern__ kern_return_t vm_object_destroy(
+ vm_object_t object,
+ kern_return_t reason);
-extern void vm_object_page_map(
+__private_extern__ void vm_object_pager_create(
+ vm_object_t object);
+
+__private_extern__ void vm_object_compressor_pager_create(
+ vm_object_t object);
+
+__private_extern__ void vm_object_page_map(
vm_object_t object,
vm_object_offset_t offset,
vm_object_size_t size,
(void *, vm_object_offset_t),
void *map_fn_data);
-#if TASK_SWAPPER
-
-extern void vm_object_res_reference(
- vm_object_t object);
-extern void vm_object_res_deallocate(
- vm_object_t object);
-#define VM_OBJ_RES_INCR(object) (object)->res_count++
-#define VM_OBJ_RES_DECR(object) (object)->res_count--
+__private_extern__ kern_return_t vm_object_upl_request(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ upl_size_t size,
+ upl_t *upl,
+ upl_page_info_t *page_info,
+ unsigned int *count,
+ upl_control_flags_t flags,
+ vm_tag_t tag);
+
+__private_extern__ kern_return_t vm_object_transpose(
+ vm_object_t object1,
+ vm_object_t object2,
+ vm_object_size_t transpose_size);
+
+__private_extern__ boolean_t vm_object_sync(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_object_size_t size,
+ boolean_t should_flush,
+ boolean_t should_return,
+ boolean_t should_iosync);
-#else /* TASK_SWAPPER */
+__private_extern__ kern_return_t vm_object_update(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_object_size_t size,
+ vm_object_offset_t *error_offset,
+ int *io_errno,
+ memory_object_return_t should_return,
+ int flags,
+ vm_prot_t prot);
+
+__private_extern__ kern_return_t vm_object_lock_request(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_object_size_t size,
+ memory_object_return_t should_return,
+ int flags,
+ vm_prot_t prot);
-#define VM_OBJ_RES_INCR(object)
-#define VM_OBJ_RES_DECR(object)
-#define vm_object_res_reference(object)
-#define vm_object_res_deallocate(object)
-#endif /* TASK_SWAPPER */
-extern vm_object_t vm_object_enter(
- ipc_port_t pager,
+__private_extern__ vm_object_t vm_object_memory_object_associate(
+ memory_object_t pager,
+ vm_object_t object,
vm_object_size_t size,
- boolean_t internal,
- boolean_t init,
boolean_t check_named);
-extern vm_object_t vm_object_copy_delayed(
- vm_object_t src_object,
- vm_object_offset_t src_offset,
- vm_object_size_t size);
+__private_extern__ void vm_object_cluster_size(
+ vm_object_t object,
+ vm_object_offset_t *start,
+ vm_size_t *length,
+ vm_object_fault_info_t fault_info,
+ uint32_t *io_streaming);
+
+__private_extern__ kern_return_t vm_object_populate_with_private(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ ppnum_t phys_page,
+ vm_size_t size);
+
+__private_extern__ void vm_object_change_wimg_mode(
+ vm_object_t object,
+ unsigned int wimg_mode);
+
+extern kern_return_t adjust_vm_object_cache(
+ vm_size_t oval,
+ vm_size_t nval);
+
+extern kern_return_t vm_object_page_op(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ int ops,
+ ppnum_t *phys_entry,
+ int *flags);
+
+extern kern_return_t vm_object_range_op(
+ vm_object_t object,
+ vm_object_offset_t offset_beg,
+ vm_object_offset_t offset_end,
+ int ops,
+ uint32_t *range);
+
+
+__private_extern__ void vm_object_reap_pages(
+ vm_object_t object,
+ int reap_type);
+#define REAP_REAP 0
+#define REAP_TERMINATE 1
+#define REAP_PURGEABLE 2
+#define REAP_DATA_FLUSH 3
+
+#if CONFIG_FREEZE
+
+__private_extern__ void
+vm_object_compressed_freezer_pageout(
+ vm_object_t object);
+
+__private_extern__ void
+vm_object_compressed_freezer_done(
+ void);
+
+#endif /* CONFIG_FREEZE */
+
+__private_extern__ void
+vm_object_pageout(
+ vm_object_t object);
+
+#if CONFIG_IOSCHED
+struct io_reprioritize_req {
+ uint64_t blkno;
+ uint32_t len;
+ int priority;
+ struct vnode *devvp;
+ queue_chain_t io_reprioritize_list;
+};
+typedef struct io_reprioritize_req *io_reprioritize_req_t;
+extern void vm_io_reprioritize_init(void);
+#endif
/*
* Event waiting handling
#define VM_OBJECT_EVENT_INITIALIZED 0
#define VM_OBJECT_EVENT_PAGER_READY 1
#define VM_OBJECT_EVENT_PAGING_IN_PROGRESS 2
-#define VM_OBJECT_EVENT_ABSENT_COUNT 3
+#define VM_OBJECT_EVENT_MAPPING_IN_PROGRESS 3
#define VM_OBJECT_EVENT_LOCK_IN_PROGRESS 4
#define VM_OBJECT_EVENT_UNCACHING 5
#define VM_OBJECT_EVENT_COPY_CALL 6
#define VM_OBJECT_EVENT_CACHING 7
+#define VM_OBJECT_EVENT_UNBLOCKED 8
+#define VM_OBJECT_EVENT_PAGING_ONLY_IN_PROGRESS 9
+
+#define VM_OBJECT_EVENT_MAX 10 /* 11 bits in "all_wanted", so 0->10 */
+
+static __inline__ wait_result_t
+vm_object_assert_wait(
+ vm_object_t object,
+ int event,
+ wait_interrupt_t interruptible)
+{
+ wait_result_t wr;
+
+ vm_object_lock_assert_exclusive(object);
+ assert(event >= 0 && event <= VM_OBJECT_EVENT_MAX);
+
+ object->all_wanted |= 1 << event;
+ wr = assert_wait((event_t)((vm_offset_t)object + event),
+ interruptible);
+ return wr;
+}
+
+static __inline__ wait_result_t
+vm_object_wait(
+ vm_object_t object,
+ int event,
+ wait_interrupt_t interruptible)
+{
+ wait_result_t wr;
+
+ vm_object_assert_wait(object, event, interruptible);
+ vm_object_unlock(object);
+ wr = thread_block(THREAD_CONTINUE_NULL);
+ return wr;
+}
+
+static __inline__ wait_result_t
+thread_sleep_vm_object(
+ vm_object_t object,
+ event_t event,
+ wait_interrupt_t interruptible)
+{
+ wait_result_t wr;
+
+#if DEVELOPMENT || DEBUG
+ if (object->Lock_owner != current_thread())
+ panic("thread_sleep_vm_object: now owner - %p\n", object);
+ object->Lock_owner = 0;
+#endif
+ wr = lck_rw_sleep(&object->Lock,
+ LCK_SLEEP_PROMOTED_PRI,
+ event,
+ interruptible);
+#if DEVELOPMENT || DEBUG
+ object->Lock_owner = current_thread();
+#endif
+ return wr;
+}
+
+static __inline__ wait_result_t
+vm_object_sleep(
+ vm_object_t object,
+ int event,
+ wait_interrupt_t interruptible)
+{
+ wait_result_t wr;
+
+ vm_object_lock_assert_exclusive(object);
+ assert(event >= 0 && event <= VM_OBJECT_EVENT_MAX);
+
+ object->all_wanted |= 1 << event;
+ wr = thread_sleep_vm_object(object,
+ (event_t)((vm_offset_t)object + event),
+ interruptible);
+ return wr;
+}
+
+static __inline__ void
+vm_object_wakeup(
+ vm_object_t object,
+ int event)
+{
+ vm_object_lock_assert_exclusive(object);
+ assert(event >= 0 && event <= VM_OBJECT_EVENT_MAX);
+
+ if (object->all_wanted & (1 << event))
+ thread_wakeup((event_t)((vm_offset_t)object + event));
+ object->all_wanted &= ~(1 << event);
+}
+
+static __inline__ void
+vm_object_set_wanted(
+ vm_object_t object,
+ int event)
+{
+ vm_object_lock_assert_exclusive(object);
+ assert(event >= 0 && event <= VM_OBJECT_EVENT_MAX);
+
+ object->all_wanted |= (1 << event);
+}
+
+static __inline__ int
+vm_object_wanted(
+ vm_object_t object,
+ int event)
+{
+ vm_object_lock_assert_held(object);
+ assert(event >= 0 && event <= VM_OBJECT_EVENT_MAX);
+
+ return object->all_wanted & (1 << event);
+}
-#define vm_object_assert_wait(object, event, interruptible) \
- MACRO_BEGIN \
- (object)->all_wanted |= 1 << (event); \
- assert_wait((event_t)((vm_offset_t)(object)+(event)),(interruptible)); \
- MACRO_END
-
-#define vm_object_wait(object, event, interruptible) \
+/*
+ * Routines implemented as macros
+ */
+#ifdef VM_PIP_DEBUG
+#include <libkern/OSDebug.h>
+#define VM_PIP_DEBUG_BEGIN(object) \
MACRO_BEGIN \
- vm_object_assert_wait((object),(event),(interruptible)); \
- vm_object_unlock(object); \
- thread_block((void (*)(void)) 0); \
+ int pip = ((object)->paging_in_progress + \
+ (object)->activity_in_progress); \
+ if (pip < VM_PIP_DEBUG_MAX_REFS) { \
+ (void) OSBacktrace(&(object)->pip_holders[pip].pip_retaddr[0], \
+ VM_PIP_DEBUG_STACK_FRAMES); \
+ } \
MACRO_END
+#else /* VM_PIP_DEBUG */
+#define VM_PIP_DEBUG_BEGIN(object)
+#endif /* VM_PIP_DEBUG */
-#define vm_object_wakeup(object, event) \
+#define vm_object_activity_begin(object) \
MACRO_BEGIN \
- if ((object)->all_wanted & (1 << (event))) \
- thread_wakeup((event_t)((vm_offset_t)(object) + (event))); \
- (object)->all_wanted &= ~(1 << (event)); \
+ vm_object_lock_assert_exclusive((object)); \
+ VM_PIP_DEBUG_BEGIN((object)); \
+ (object)->activity_in_progress++; \
+ if ((object)->activity_in_progress == 0) { \
+ panic("vm_object_activity_begin(%p): overflow\n", (object));\
+ } \
MACRO_END
-#define vm_object_set_wanted(object, event) \
+#define vm_object_activity_end(object) \
MACRO_BEGIN \
- ((object)->all_wanted |= (1 << (event))); \
+ vm_object_lock_assert_exclusive((object)); \
+ if ((object)->activity_in_progress == 0) { \
+ panic("vm_object_activity_end(%p): underflow\n", (object));\
+ } \
+ (object)->activity_in_progress--; \
+ if ((object)->paging_in_progress == 0 && \
+ (object)->activity_in_progress == 0) \
+ vm_object_wakeup((object), \
+ VM_OBJECT_EVENT_PAGING_IN_PROGRESS); \
MACRO_END
-#define vm_object_wanted(object, event) \
- ((object)->all_wanted & (1 << (event)))
-
-/*
- * Routines implemented as macros
- */
-
-#define vm_object_paging_begin(object) \
+#define vm_object_paging_begin(object) \
MACRO_BEGIN \
+ vm_object_lock_assert_exclusive((object)); \
+ VM_PIP_DEBUG_BEGIN((object)); \
(object)->paging_in_progress++; \
+ if ((object)->paging_in_progress == 0) { \
+ panic("vm_object_paging_begin(%p): overflow\n", (object));\
+ } \
MACRO_END
-#define vm_object_paging_end(object) \
+#define vm_object_paging_end(object) \
MACRO_BEGIN \
- assert((object)->paging_in_progress != 0); \
- if (--(object)->paging_in_progress == 0) { \
- vm_object_wakeup(object, \
- VM_OBJECT_EVENT_PAGING_IN_PROGRESS); \
+ vm_object_lock_assert_exclusive((object)); \
+ if ((object)->paging_in_progress == 0) { \
+ panic("vm_object_paging_end(%p): underflow\n", (object));\
+ } \
+ (object)->paging_in_progress--; \
+ if ((object)->paging_in_progress == 0) { \
+ vm_object_wakeup((object), \
+ VM_OBJECT_EVENT_PAGING_ONLY_IN_PROGRESS); \
+ if ((object)->activity_in_progress == 0) \
+ vm_object_wakeup((object), \
+ VM_OBJECT_EVENT_PAGING_IN_PROGRESS); \
} \
MACRO_END
#define vm_object_paging_wait(object, interruptible) \
MACRO_BEGIN \
- while ((object)->paging_in_progress != 0) { \
- vm_object_wait( (object), \
+ vm_object_lock_assert_exclusive((object)); \
+ while ((object)->paging_in_progress != 0 || \
+ (object)->activity_in_progress != 0) { \
+ wait_result_t _wr; \
+ \
+ _wr = vm_object_sleep((object), \
VM_OBJECT_EVENT_PAGING_IN_PROGRESS, \
(interruptible)); \
- vm_object_lock(object); \
\
- /*XXX if ((interruptible) && */ \
- /*XXX (current_thread()->wait_result != THREAD_AWAKENED))*/ \
+ /*XXX if ((interruptible) && (_wr != THREAD_AWAKENED))*/\
/*XXX break; */ \
} \
MACRO_END
-#define vm_object_absent_assert_wait(object, interruptible) \
+#define vm_object_paging_only_wait(object, interruptible) \
MACRO_BEGIN \
- vm_object_assert_wait( (object), \
- VM_OBJECT_EVENT_ABSENT_COUNT, \
- (interruptible)); \
+ vm_object_lock_assert_exclusive((object)); \
+ while ((object)->paging_in_progress != 0) { \
+ wait_result_t _wr; \
+ \
+ _wr = vm_object_sleep((object), \
+ VM_OBJECT_EVENT_PAGING_ONLY_IN_PROGRESS,\
+ (interruptible)); \
+ \
+ /*XXX if ((interruptible) && (_wr != THREAD_AWAKENED))*/\
+ /*XXX break; */ \
+ } \
MACRO_END
-#define vm_object_absent_release(object) \
+#define vm_object_mapping_begin(object) \
+ MACRO_BEGIN \
+ vm_object_lock_assert_exclusive((object)); \
+ assert(! (object)->mapping_in_progress); \
+ (object)->mapping_in_progress = TRUE; \
+ MACRO_END
+
+#define vm_object_mapping_end(object) \
MACRO_BEGIN \
- (object)->absent_count--; \
+ vm_object_lock_assert_exclusive((object)); \
+ assert((object)->mapping_in_progress); \
+ (object)->mapping_in_progress = FALSE; \
vm_object_wakeup((object), \
- VM_OBJECT_EVENT_ABSENT_COUNT); \
+ VM_OBJECT_EVENT_MAPPING_IN_PROGRESS); \
MACRO_END
-/*
- * Object locking macros
- */
+#define vm_object_mapping_wait(object, interruptible) \
+ MACRO_BEGIN \
+ vm_object_lock_assert_exclusive((object)); \
+ while ((object)->mapping_in_progress) { \
+ wait_result_t _wr; \
+ \
+ _wr = vm_object_sleep((object), \
+ VM_OBJECT_EVENT_MAPPING_IN_PROGRESS, \
+ (interruptible)); \
+ /*XXX if ((interruptible) && (_wr != THREAD_AWAKENED))*/\
+ /*XXX break; */ \
+ } \
+ assert(!(object)->mapping_in_progress); \
+ MACRO_END
+
+
-#define vm_object_lock_init(object) mutex_init(&(object)->Lock, ETAP_VM_OBJ)
-#define vm_object_lock(object) mutex_lock(&(object)->Lock)
-#define vm_object_unlock(object) mutex_unlock(&(object)->Lock)
-#define vm_object_lock_try(object) mutex_try(&(object)->Lock)
+#define vm_object_round_page(x) (((vm_object_offset_t)(x) + PAGE_MASK) & ~((signed)PAGE_MASK))
+#define vm_object_trunc_page(x) ((vm_object_offset_t)(x) & ~((signed)PAGE_MASK))
+
+extern void vm_object_cache_add(vm_object_t);
+extern void vm_object_cache_remove(vm_object_t);
+extern int vm_object_cache_evict(int, int);
+
+#define VM_OBJECT_OWNER_DISOWNED ((task_t) -1)
+#define VM_OBJECT_OWNER(object) \
+ ((((object)->purgable == VM_PURGABLE_DENY && \
+ (object)->vo_ledger_tag == 0) || \
+ (object)->vo_owner == TASK_NULL) \
+ ? TASK_NULL /* not owned */ \
+ : (((object)->vo_owner == VM_OBJECT_OWNER_DISOWNED) \
+ ? kernel_task /* disowned -> kernel */ \
+ : (object)->vo_owner)) /* explicit owner */ \
+
+extern void vm_object_ledger_tag_ledgers(
+ vm_object_t object,
+ int *ledger_idx_volatile,
+ int *ledger_idx_nonvolatile,
+ int *ledger_idx_volatile_compressed,
+ int *ledger_idx_nonvolatile_compressed,
+ boolean_t *do_footprint);
+extern kern_return_t vm_object_ownership_change(
+ vm_object_t object,
+ int ledger_tag,
+ task_t owner,
+ boolean_t task_objq_locked);
#endif /* _VM_VM_OBJECT_H_ */
projects / apple / xnu.git / blobdiff