X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/c910b4d9d2451126ae3917b931cd4390c11e1d52..c6bf4f310a33a9262d455ea4d3f0630b1255e3fe:/bsd/kern/kdebug.c diff --git a/bsd/kern/kdebug.c b/bsd/kern/kdebug.c index ee4b63f40..eb78ca89a 100644 --- a/bsd/kern/kdebug.c +++ b/bsd/kern/kdebug.c @@ -1,14 +1,14 @@ /* - * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2000-2019 Apple 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 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, @@ -16,12 +16,10 @@ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. - * + * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ -#include - #include #include #include @@ -29,1557 +27,4627 @@ #include #include #include +#include +#include #include +#include +#include -#define HZ 100 #include #include #include +#include +#include #include +#include +#include + +#if defined(__i386__) || defined(__x86_64__) +#include +#include +#include +#include +#endif + +#include + #include #include #include +#include +#include +#include +#include +#include #include #include +#include +#include #include -#include +#include -#include /* for host_info() */ +#include +#include +#include +#include +#include +#include /* for isset() */ + +#include /* for host_info() */ #include -/* XXX should have prototypes, but Mach does not provide one */ -void task_act_iterate_wth_args(task_t, void(*)(thread_t, void *), void *); -int cpu_number(void); /* XXX include path broken */ +#include +#include + +/* + * IOP(s) + * + * IOP(s) are auxiliary cores that want to participate in kdebug event logging. + * They are registered dynamically. Each is assigned a cpu_id at registration. + * + * NOTE: IOP trace events may not use the same clock hardware as "normal" + * cpus. There is an effort made to synchronize the IOP timebase with the + * AP, but it should be understood that there may be discrepancies. + * + * Once registered, an IOP is permanent, it cannot be unloaded/unregistered. + * The current implementation depends on this for thread safety. + * + * New registrations occur by allocating an kd_iop struct and assigning + * a provisional cpu_id of list_head->cpu_id + 1. Then a CAS to claim the + * list_head pointer resolves any races. + * + * You may safely walk the kd_iops list at any time, without holding locks. + * + * When allocating buffers, the current kd_iops head is captured. Any operations + * that depend on the buffer state (such as flushing IOP traces on reads, + * etc.) should use the captured list head. This will allow registrations to + * take place while trace is in use. + */ + +typedef struct kd_iop { + kd_callback_t callback; + uint32_t cpu_id; + uint64_t last_timestamp; /* Prevent timer rollback */ + struct kd_iop* next; +} kd_iop_t; + +static kd_iop_t* kd_iops = NULL; + +/* + * Typefilter(s) + * + * A typefilter is a 8KB bitmap that is used to selectively filter events + * being recorded. It is able to individually address every class & subclass. + * + * There is a shared typefilter in the kernel which is lazily allocated. Once + * allocated, the shared typefilter is never deallocated. The shared typefilter + * is also mapped on demand into userspace processes that invoke kdebug_trace + * API from Libsyscall. When mapped into a userspace process, the memory is + * read only, and does not have a fixed address. + * + * It is a requirement that the kernel's shared typefilter always pass DBG_TRACE + * events. This is enforced automatically, by having the needed bits set any + * time the shared typefilter is mutated. + */ + +typedef uint8_t* typefilter_t; + +static typefilter_t kdbg_typefilter; +static mach_port_t kdbg_typefilter_memory_entry; + +/* + * There are 3 combinations of page sizes: + * + * 4KB / 4KB + * 4KB / 16KB + * 16KB / 16KB + * + * The typefilter is exactly 8KB. In the first two scenarios, we would like + * to use 2 pages exactly; in the third scenario we must make certain that + * a full page is allocated so we do not inadvertantly share 8KB of random + * data to userspace. The round_page_32 macro rounds to kernel page size. + */ +#define TYPEFILTER_ALLOC_SIZE MAX(round_page_32(KDBG_TYPEFILTER_BITMAP_SIZE), KDBG_TYPEFILTER_BITMAP_SIZE) + +static typefilter_t +typefilter_create(void) +{ + typefilter_t tf; + if (KERN_SUCCESS == kmem_alloc(kernel_map, (vm_offset_t*)&tf, TYPEFILTER_ALLOC_SIZE, VM_KERN_MEMORY_DIAG)) { + memset(&tf[KDBG_TYPEFILTER_BITMAP_SIZE], 0, TYPEFILTER_ALLOC_SIZE - KDBG_TYPEFILTER_BITMAP_SIZE); + return tf; + } + return NULL; +} + +static void +typefilter_deallocate(typefilter_t tf) +{ + assert(tf != NULL); + assert(tf != kdbg_typefilter); + kmem_free(kernel_map, (vm_offset_t)tf, TYPEFILTER_ALLOC_SIZE); +} + +static void +typefilter_copy(typefilter_t dst, typefilter_t src) +{ + assert(src != NULL); + assert(dst != NULL); + memcpy(dst, src, KDBG_TYPEFILTER_BITMAP_SIZE); +} + +static void +typefilter_reject_all(typefilter_t tf) +{ + assert(tf != NULL); + memset(tf, 0, KDBG_TYPEFILTER_BITMAP_SIZE); +} + +static void +typefilter_allow_all(typefilter_t tf) +{ + assert(tf != NULL); + memset(tf, ~0, KDBG_TYPEFILTER_BITMAP_SIZE); +} + +static void +typefilter_allow_class(typefilter_t tf, uint8_t class) +{ + assert(tf != NULL); + const uint32_t BYTES_PER_CLASS = 256 / 8; // 256 subclasses, 1 bit each + memset(&tf[class * BYTES_PER_CLASS], 0xFF, BYTES_PER_CLASS); +} + +static void +typefilter_allow_csc(typefilter_t tf, uint16_t csc) +{ + assert(tf != NULL); + setbit(tf, csc); +} + +static bool +typefilter_is_debugid_allowed(typefilter_t tf, uint32_t id) +{ + assert(tf != NULL); + return isset(tf, KDBG_EXTRACT_CSC(id)); +} + +static mach_port_t +typefilter_create_memory_entry(typefilter_t tf) +{ + assert(tf != NULL); + + mach_port_t memory_entry = MACH_PORT_NULL; + memory_object_size_t size = TYPEFILTER_ALLOC_SIZE; + + mach_make_memory_entry_64(kernel_map, + &size, + (memory_object_offset_t)tf, + VM_PROT_READ, + &memory_entry, + MACH_PORT_NULL); + + return memory_entry; +} + +static int kdbg_copyin_typefilter(user_addr_t addr, size_t size); +static void kdbg_enable_typefilter(void); +static void kdbg_disable_typefilter(void); + +/* + * External prototypes + */ + +void task_act_iterate_wth_args(task_t, void (*)(thread_t, void *), void *); +int cpu_number(void); /* XXX include path broken */ +void commpage_update_kdebug_state(void); /* XXX sign */ + +extern int log_leaks; + +/* + * This flag is for testing purposes only -- it's highly experimental and tools + * have not been updated to support it. + */ +static bool kdbg_continuous_time = false; + +static inline uint64_t +kdbg_timestamp(void) +{ + if (kdbg_continuous_time) { + return mach_continuous_time(); + } else { + return mach_absolute_time(); + } +} + +static int kdbg_debug = 0; + +#if KDEBUG_MOJO_TRACE +#include +static void kdebug_serial_print( /* forward */ + uint32_t, uint32_t, uint64_t, + uintptr_t, uintptr_t, uintptr_t, uintptr_t, uintptr_t); +#endif -/* XXX should probably be static, but it's debugging code... */ -int kdbg_read(user_addr_t, size_t *); -void kdbg_control_chud(int, void *); int kdbg_control(int *, u_int, user_addr_t, size_t *); -int kdbg_getentropy (user_addr_t, size_t *, int); -int kdbg_readmap(user_addr_t, size_t *); -int kdbg_getreg(kd_regtype *); -int kdbg_setreg(kd_regtype *); -int kdbg_setrtcdec(kd_regtype *); -int kdbg_setpidex(kd_regtype *); -int kdbg_setpid(kd_regtype *); -void kdbg_mapinit(void); -int kdbg_reinit(void); -int kdbg_bootstrap(void); - -static int create_buffers(void); + +static int kdbg_read(user_addr_t, size_t *, vnode_t, vfs_context_t, uint32_t); +static int kdbg_readcpumap(user_addr_t, size_t *); +static int kdbg_readthrmap_v3(user_addr_t, size_t, int); +static int kdbg_readcurthrmap(user_addr_t, size_t *); +static int kdbg_setreg(kd_regtype *); +static int kdbg_setpidex(kd_regtype *); +static int kdbg_setpid(kd_regtype *); +static void kdbg_thrmap_init(void); +static int kdbg_reinit(bool); +static int kdbg_bootstrap(bool); +static int kdbg_test(size_t flavor); + +static int kdbg_write_v1_header(bool write_thread_map, vnode_t vp, vfs_context_t ctx); +static int kdbg_write_thread_map(vnode_t vp, vfs_context_t ctx); +static int kdbg_copyout_thread_map(user_addr_t buffer, size_t *buffer_size); +static void kdbg_clear_thread_map(void); + +static bool kdbg_wait(uint64_t timeout_ms, bool locked_wait); +static void kdbg_wakeup(void); + +int kdbg_cpumap_init_internal(kd_iop_t* iops, uint32_t cpu_count, + uint8_t** cpumap, uint32_t* cpumap_size); + +static kd_threadmap *kdbg_thrmap_init_internal(unsigned int count, + unsigned int *mapsize, + unsigned int *mapcount); + +static bool kdebug_current_proc_enabled(uint32_t debugid); +static errno_t kdebug_check_trace_string(uint32_t debugid, uint64_t str_id); + +int kdbg_write_v3_header(user_addr_t, size_t *, int); +int kdbg_write_v3_chunk_header(user_addr_t buffer, uint32_t tag, + uint32_t sub_tag, uint64_t length, + vnode_t vp, vfs_context_t ctx); + +user_addr_t kdbg_write_v3_event_chunk_header(user_addr_t buffer, uint32_t tag, + uint64_t length, vnode_t vp, + vfs_context_t ctx); + +// Helper functions + +static int create_buffers(bool); static void delete_buffers(void); +extern int tasks_count; +extern int threads_count; extern void IOSleep(int); -#ifdef ppc -extern uint32_t maxDec; -#endif - /* trace enable status */ unsigned int kdebug_enable = 0; -/* track timestamps for security server's entropy needs */ -uint64_t * kd_entropy_buffer = 0; -unsigned int kd_entropy_bufsize = 0; -unsigned int kd_entropy_count = 0; -unsigned int kd_entropy_indx = 0; -unsigned int kd_entropy_buftomem = 0; +/* A static buffer to record events prior to the start of regular logging */ +#define KD_EARLY_BUFFER_SIZE (16 * 1024) +#define KD_EARLY_BUFFER_NBUFS (KD_EARLY_BUFFER_SIZE / sizeof(kd_buf)) +#if CONFIG_EMBEDDED +/* + * On embedded, the space for this is carved out by osfmk/arm/data.s -- clang + * has problems aligning to greater than 4K. + */ +extern kd_buf kd_early_buffer[KD_EARLY_BUFFER_NBUFS]; +#else /* CONFIG_EMBEDDED */ +__attribute__((aligned(KD_EARLY_BUFFER_SIZE))) +static kd_buf kd_early_buffer[KD_EARLY_BUFFER_NBUFS]; +#endif /* !CONFIG_EMBEDDED */ + +static unsigned int kd_early_index = 0; +static bool kd_early_overflow = false; +static bool kd_early_done = false; + +#define SLOW_NOLOG 0x01 +#define SLOW_CHECKS 0x02 + +#define EVENTS_PER_STORAGE_UNIT 2048 +#define MIN_STORAGE_UNITS_PER_CPU 4 + +#define POINTER_FROM_KDS_PTR(x) (&kd_bufs[x.buffer_index].kdsb_addr[x.offset]) + +union kds_ptr { + struct { + uint32_t buffer_index:21; + uint16_t offset:11; + }; + uint32_t raw; +}; -#define SLOW_NOLOG 0x01 -#define SLOW_CHECKS 0x02 -#define SLOW_ENTROPY 0x04 - -unsigned int kdebug_slowcheck=SLOW_NOLOG; +struct kd_storage { + union kds_ptr kds_next; + uint32_t kds_bufindx; + uint32_t kds_bufcnt; + uint32_t kds_readlast; + bool kds_lostevents; + uint64_t kds_timestamp; -unsigned int kd_cpus; + kd_buf kds_records[EVENTS_PER_STORAGE_UNIT]; +}; -struct kd_bufinfo { - kd_buf * kd_stop; - kd_buf * kd_bufptr; - kd_buf * kd_buffer; - kd_buf * kd_buflast; - kd_buf * kd_readlast; - int kd_wrapped; /* plus, the global flag KDBG_WRAPPED is set if one of the buffers has wrapped */ - uint64_t kd_prev_timebase; - int kd_pad[24]; /* pad out to 128 bytes so that no cache line is shared between CPUs */ +#define MAX_BUFFER_SIZE (1024 * 1024 * 128) +#define N_STORAGE_UNITS_PER_BUFFER (MAX_BUFFER_SIZE / sizeof(struct kd_storage)) +static_assert(N_STORAGE_UNITS_PER_BUFFER <= 0x7ff, + "shoudn't overflow kds_ptr.offset"); +struct kd_storage_buffers { + struct kd_storage *kdsb_addr; + uint32_t kdsb_size; }; -struct kd_bufinfo *kdbip = NULL; +#define KDS_PTR_NULL 0xffffffff +struct kd_storage_buffers *kd_bufs = NULL; +int n_storage_units = 0; +unsigned int n_storage_buffers = 0; +int n_storage_threshold = 0; +int kds_waiter = 0; + +#pragma pack(0) +struct kd_bufinfo { + union kds_ptr kd_list_head; + union kds_ptr kd_list_tail; + bool kd_lostevents; + uint32_t _pad; + uint64_t kd_prev_timebase; + uint32_t num_bufs; +} __attribute__((aligned(MAX_CPU_CACHE_LINE_SIZE))); -#define KDCOPYBUF_COUNT 1024 -#define KDCOPYBUF_SIZE (KDCOPYBUF_COUNT * sizeof(kd_buf)) -kd_buf *kdcopybuf = NULL; +/* + * In principle, this control block can be shared in DRAM with other + * coprocessors and runtimes, for configuring what tracing is enabled. + */ +struct kd_ctrl_page_t { + union kds_ptr kds_free_list; + uint32_t enabled :1; + uint32_t _pad0 :31; + int kds_inuse_count; + uint32_t kdebug_flags; + uint32_t kdebug_slowcheck; + uint64_t oldest_time; + /* + * The number of kd_bufinfo structs allocated may not match the current + * number of active cpus. We capture the iops list head at initialization + * which we could use to calculate the number of cpus we allocated data for, + * unless it happens to be null. To avoid that case, we explicitly also + * capture a cpu count. + */ + kd_iop_t* kdebug_iops; + uint32_t kdebug_cpus; +} kd_ctrl_page = { + .kds_free_list = {.raw = KDS_PTR_NULL}, + .kdebug_slowcheck = SLOW_NOLOG, + .oldest_time = 0 +}; -unsigned int nkdbufs = 8192; -unsigned int kd_bufsize = 0; -unsigned int kdebug_flags = 0; -unsigned int kdlog_beg=0; -unsigned int kdlog_end=0; -unsigned int kdlog_value1=0; -unsigned int kdlog_value2=0; -unsigned int kdlog_value3=0; -unsigned int kdlog_value4=0; +#pragma pack() -static lck_mtx_t * kd_trace_mtx_sysctl; -static lck_grp_t * kd_trace_mtx_sysctl_grp; -static lck_attr_t * kd_trace_mtx_sysctl_attr; -static lck_grp_attr_t *kd_trace_mtx_sysctl_grp_attr; +struct kd_bufinfo *kdbip = NULL; -static lck_grp_t *stackshot_subsys_lck_grp; -static lck_grp_attr_t *stackshot_subsys_lck_grp_attr; -static lck_attr_t *stackshot_subsys_lck_attr; -static lck_mtx_t stackshot_subsys_mutex; +#define KDCOPYBUF_COUNT 8192 +#define KDCOPYBUF_SIZE (KDCOPYBUF_COUNT * sizeof(kd_buf)) -void *stackshot_snapbuf = NULL; +#define PAGE_4KB 4096 +#define PAGE_16KB 16384 -int -stack_snapshot2(pid_t pid, user_addr_t tracebuf, uint32_t tracebuf_size, uint32_t options, register_t *retval); +kd_buf *kdcopybuf = NULL; -extern void -kdp_snapshot_preflight(int pid, void *tracebuf, uint32_t tracebuf_size, uint32_t options); +unsigned int nkdbufs = 0; +unsigned int kdlog_beg = 0; +unsigned int kdlog_end = 0; +unsigned int kdlog_value1 = 0; +unsigned int kdlog_value2 = 0; +unsigned int kdlog_value3 = 0; +unsigned int kdlog_value4 = 0; -extern int -kdp_stack_snapshot_geterror(void); -extern unsigned int -kdp_stack_snapshot_bytes_traced(void); +static lck_spin_t * kdw_spin_lock; +static lck_spin_t * kds_spin_lock; kd_threadmap *kd_mapptr = 0; unsigned int kd_mapsize = 0; unsigned int kd_mapcount = 0; -unsigned int kd_maptomem = 0; -pid_t global_state_pid = -1; /* Used to control exclusive use of kd_buffer */ +off_t RAW_file_offset = 0; +int RAW_file_written = 0; + +#define RAW_FLUSH_SIZE (2 * 1024 * 1024) + +/* + * A globally increasing counter for identifying strings in trace. Starts at + * 1 because 0 is a reserved return value. + */ +__attribute__((aligned(MAX_CPU_CACHE_LINE_SIZE))) +static uint64_t g_curr_str_id = 1; + +#define STR_ID_SIG_OFFSET (48) +#define STR_ID_MASK ((1ULL << STR_ID_SIG_OFFSET) - 1) +#define STR_ID_SIG_MASK (~STR_ID_MASK) + +/* + * A bit pattern for identifying string IDs generated by + * kdebug_trace_string(2). + */ +static uint64_t g_str_id_signature = (0x70acULL << STR_ID_SIG_OFFSET); -#define DBG_FUNC_MASK 0xfffffffc +#define INTERRUPT 0x01050000 +#define MACH_vmfault 0x01300008 +#define BSC_SysCall 0x040c0000 +#define MACH_SysCall 0x010c0000 /* task to string structure */ -struct tts -{ - task_t task; /* from procs task */ - pid_t pid; /* from procs p_pid */ - char task_comm[20]; /* from procs p_comm */ +struct tts { + task_t task; /* from procs task */ + pid_t pid; /* from procs p_pid */ + char task_comm[20];/* from procs p_comm */ }; typedef struct tts tts_t; -struct krt -{ - kd_threadmap *map; /* pointer to the map buffer */ - int count; - int maxcount; - struct tts *atts; +struct krt { + kd_threadmap *map; /* pointer to the map buffer */ + int count; + int maxcount; + struct tts *atts; }; -typedef struct krt krt_t; +/* + * TRACE file formats... + * + * RAW_VERSION0 + * + * uint32_t #threadmaps + * kd_threadmap[] + * kd_buf[] + * + * RAW_VERSION1 + * + * RAW_header, with version_no set to RAW_VERSION1 + * kd_threadmap[] + * Empty space to pad alignment to the nearest page boundary. + * kd_buf[] + * + * RAW_VERSION1+ + * + * RAW_header, with version_no set to RAW_VERSION1 + * kd_threadmap[] + * kd_cpumap_header, with version_no set to RAW_VERSION1 + * kd_cpumap[] + * Empty space to pad alignment to the nearest page boundary. + * kd_buf[] + * + * V1+ implementation details... + * + * It would have been nice to add the cpumap data "correctly", but there were + * several obstacles. Existing code attempts to parse both V1 and V0 files. + * Due to the fact that V0 has no versioning or header, the test looks like + * this: + * + * // Read header + * if (header.version_no != RAW_VERSION1) { // Assume V0 } + * + * If we add a VERSION2 file format, all existing code is going to treat that + * as a VERSION0 file when reading it, and crash terribly when trying to read + * RAW_VERSION2 threadmap entries. + * + * To differentiate between a V1 and V1+ file, read as V1 until you reach + * the padding bytes. Then: + * + * boolean_t is_v1plus = FALSE; + * if (padding_bytes >= sizeof(kd_cpumap_header)) { + * kd_cpumap_header header = // read header; + * if (header.version_no == RAW_VERSION1) { + * is_v1plus = TRUE; + * } + * } + * + */ -/* This is for the CHUD toolkit call */ -typedef void (*kd_chudhook_fn) (unsigned int debugid, unsigned int arg1, - unsigned int arg2, unsigned int arg3, - unsigned int arg4, unsigned int arg5); +#define RAW_VERSION3 0x00001000 -kd_chudhook_fn kdebug_chudhook = 0; /* pointer to CHUD toolkit function */ +// Version 3 header +// The header chunk has the tag 0x00001000 which also serves as a magic word +// that identifies the file as a version 3 trace file. The header payload is +// a set of fixed fields followed by a variable number of sub-chunks: +/* + * ____________________________________________________________________________ + | Offset | Size | Field | + | ---------------------------------------------------------------------------- + | 0 | 4 | Tag (0x00001000) | + | 4 | 4 | Sub-tag. Represents the version of the header. | + | 8 | 8 | Length of header payload (40+8x) | + | 16 | 8 | Time base info. Two 32-bit numbers, numer/denom, | + | | | for converting timestamps to nanoseconds. | + | 24 | 8 | Timestamp of trace start. | + | 32 | 8 | Wall time seconds since Unix epoch. | + | | | As returned by gettimeofday(). | + | 40 | 4 | Wall time microseconds. As returned by gettimeofday(). | + | 44 | 4 | Local time zone offset in minutes. ( " ) | + | 48 | 4 | Type of daylight savings time correction to apply. ( " ) | + | 52 | 4 | Flags. 1 = 64-bit. Remaining bits should be written | + | | | as 0 and ignored when reading. | + | 56 | 8x | Variable number of sub-chunks. None are required. | + | | | Ignore unknown chunks. | + | ---------------------------------------------------------------------------- + */ +// NOTE: The header sub-chunks are considered part of the header chunk, +// so they must be included in the header chunk’s length field. +// The CPU map is an optional sub-chunk of the header chunk. It provides +// information about the CPUs that are referenced from the trace events. +typedef struct { + uint32_t tag; + uint32_t sub_tag; + uint64_t length; + uint32_t timebase_numer; + uint32_t timebase_denom; + uint64_t timestamp; + uint64_t walltime_secs; + uint32_t walltime_usecs; + uint32_t timezone_minuteswest; + uint32_t timezone_dst; + uint32_t flags; +} __attribute__((packed)) kd_header_v3; + +typedef struct { + uint32_t tag; + uint32_t sub_tag; + uint64_t length; +} __attribute__((packed)) kd_chunk_header_v3; + +#define V3_CONFIG 0x00001b00 +#define V3_CPU_MAP 0x00001c00 +#define V3_THREAD_MAP 0x00001d00 +#define V3_RAW_EVENTS 0x00001e00 +#define V3_NULL_CHUNK 0x00002000 + +// The current version of all kernel managed chunks is 1. The +// V3_CURRENT_CHUNK_VERSION is added to ease the simple case +// when most/all the kernel managed chunks have the same version. + +#define V3_CURRENT_CHUNK_VERSION 1 +#define V3_HEADER_VERSION V3_CURRENT_CHUNK_VERSION +#define V3_CPUMAP_VERSION V3_CURRENT_CHUNK_VERSION +#define V3_THRMAP_VERSION V3_CURRENT_CHUNK_VERSION +#define V3_EVENT_DATA_VERSION V3_CURRENT_CHUNK_VERSION -__private_extern__ void stackshot_lock_init( void ) __attribute__((section("__TEXT, initcode"))); +typedef struct krt krt_t; -/* Support syscall SYS_kdebug_trace */ -int -kdebug_trace(__unused struct proc *p, struct kdebug_trace_args *uap, __unused register_t *retval) +static uint32_t +kdbg_cpu_count(bool early_trace) { - if ( (kdebug_enable == 0) ) - return(EINVAL); - - kernel_debug(uap->code, uap->arg1, uap->arg2, uap->arg3, uap->arg4, 0); - return(0); + if (early_trace) { +#if CONFIG_EMBEDDED + return ml_get_cpu_count(); +#else + return max_ncpus; +#endif + } + + host_basic_info_data_t hinfo; + mach_msg_type_number_t count = HOST_BASIC_INFO_COUNT; + host_info((host_t)1 /* BSD_HOST */, HOST_BASIC_INFO, (host_info_t)&hinfo, &count); + assert(hinfo.logical_cpu_max > 0); + return hinfo.logical_cpu_max; } -static int -create_buffers(void) +#if MACH_ASSERT +#if CONFIG_EMBEDDED +static bool +kdbg_iop_list_is_valid(kd_iop_t* iop) { - unsigned int cpu, i; - int nentries; - - nentries = nkdbufs / kd_cpus; - nkdbufs = nentries * kd_cpus; - - kd_bufsize = nentries * sizeof(kd_buf); - - bzero((char *)kdbip, sizeof(struct kd_bufinfo) * kd_cpus); - - if (kdcopybuf == 0) { - if (kmem_alloc(kernel_map, (unsigned int *)&kdcopybuf, (vm_size_t)KDCOPYBUF_SIZE) != KERN_SUCCESS) - return(ENOMEM); + if (iop) { + /* Is list sorted by cpu_id? */ + kd_iop_t* temp = iop; + do { + assert(!temp->next || temp->next->cpu_id == temp->cpu_id - 1); + assert(temp->next || (temp->cpu_id == kdbg_cpu_count(false) || temp->cpu_id == kdbg_cpu_count(true))); + } while ((temp = temp->next)); + + /* Does each entry have a function and a name? */ + temp = iop; + do { + assert(temp->callback.func); + assert(strlen(temp->callback.iop_name) < sizeof(temp->callback.iop_name)); + } while ((temp = temp->next)); } - for (cpu = 0; cpu < kd_cpus; cpu++) { - if (kmem_alloc(kernel_map, (unsigned int *)&kdbip[cpu].kd_buffer, kd_bufsize) != KERN_SUCCESS) - break; - } - if (cpu < kd_cpus) { - for (i = 0; i < cpu; i++) - kmem_free(kernel_map, (vm_offset_t)kdbip[i].kd_buffer, kd_bufsize); - kd_bufsize = 0; - kmem_free(kernel_map, (vm_offset_t)kdcopybuf, KDCOPYBUF_SIZE); - kdcopybuf = NULL; - - return(ENOMEM); - } - for (cpu = 0; cpu < kd_cpus; cpu++) { - kdbip[cpu].kd_bufptr = kdbip[cpu].kd_buffer; - kdbip[cpu].kd_buflast = &kdbip[cpu].kd_bufptr[nentries]; - kdbip[cpu].kd_readlast = kdbip[cpu].kd_bufptr; + return true; +} + +static bool +kdbg_iop_list_contains_cpu_id(kd_iop_t* list, uint32_t cpu_id) +{ + while (list) { + if (list->cpu_id == cpu_id) { + return true; + } + list = list->next; } - kdebug_flags |= KDBG_BUFINIT; - return(0); + return false; } - +#endif /* CONFIG_EMBEDDED */ +#endif /* MACH_ASSERT */ static void -delete_buffers(void) +kdbg_iop_list_callback(kd_iop_t* iop, kd_callback_type type, void* arg) { - unsigned int cpu; - - if (kd_bufsize && (kdebug_flags & KDBG_BUFINIT)) { - for (cpu = 0; cpu < kd_cpus; cpu++) - kmem_free(kernel_map, (vm_offset_t)kdbip[cpu].kd_buffer, kd_bufsize); - kd_bufsize = 0; - } - if (kdcopybuf) { - kmem_free(kernel_map, (vm_offset_t)kdcopybuf, KDCOPYBUF_SIZE); - kdcopybuf = NULL; + while (iop) { + iop->callback.func(iop->callback.context, type, arg); + iop = iop->next; } - kdebug_flags &= ~KDBG_BUFINIT; } +static lck_grp_t *kdebug_lck_grp = NULL; static void -kernel_debug_internal(unsigned int debugid, unsigned int arg1, unsigned int arg2, unsigned int arg3, - unsigned int arg4, unsigned int arg5, int entropy_flag) +kdbg_set_tracing_enabled(bool enabled, uint32_t trace_type) { - int s; - kd_buf * kd; - struct proc *curproc; - unsigned long long now; - int cpu; - - s = ml_set_interrupts_enabled(FALSE); + /* + * Drain any events from IOPs before making the state change. On + * enabling, this removes any stale events from before tracing. On + * disabling, this saves any events up to the point tracing is disabled. + */ + kdbg_iop_list_callback(kd_ctrl_page.kdebug_iops, KD_CALLBACK_SYNC_FLUSH, + NULL); - now = mach_absolute_time() & KDBG_TIMESTAMP_MASK; - cpu = cpu_number(); + int s = ml_set_interrupts_enabled(false); + lck_spin_lock_grp(kds_spin_lock, kdebug_lck_grp); - if (kdebug_enable & KDEBUG_ENABLE_CHUD) { - if (kdebug_chudhook) - kdebug_chudhook(debugid, arg1, arg2, arg3, arg4, arg5); - - if ( !(kdebug_enable & (KDEBUG_ENABLE_ENTROPY | KDEBUG_ENABLE_TRACE))) - goto out; - } - - if (kdebug_slowcheck == 0) - goto record_trace; - - if (entropy_flag && (kdebug_enable & KDEBUG_ENABLE_ENTROPY)) - { - if (kd_entropy_indx < kd_entropy_count) - { - kd_entropy_buffer [ kd_entropy_indx] = mach_absolute_time(); - kd_entropy_indx++; - } - - if (kd_entropy_indx == kd_entropy_count) - { - /* Disable entropy collection */ - kdebug_enable &= ~KDEBUG_ENABLE_ENTROPY; - kdebug_slowcheck &= ~SLOW_ENTROPY; - } - } - - if ( (kdebug_slowcheck & SLOW_NOLOG) ) - goto out; - - if (kdebug_flags & KDBG_PIDCHECK) - { - /* If kdebug flag is not set for current proc, return */ - curproc = current_proc(); - if ((curproc && !(curproc->p_kdebug)) && - ((debugid&0xffff0000) != (MACHDBG_CODE(DBG_MACH_SCHED, 0) | DBG_FUNC_NONE))) - goto out; - } - else if (kdebug_flags & KDBG_PIDEXCLUDE) - { - /* If kdebug flag is set for current proc, return */ - curproc = current_proc(); - if ((curproc && curproc->p_kdebug) && - ((debugid&0xffff0000) != (MACHDBG_CODE(DBG_MACH_SCHED, 0) | DBG_FUNC_NONE))) - goto out; - } + if (enabled) { + /* + * The oldest valid time is now; reject past events from IOPs. + */ + kd_ctrl_page.oldest_time = kdbg_timestamp(); + kdebug_enable |= trace_type; + kd_ctrl_page.kdebug_slowcheck &= ~SLOW_NOLOG; + kd_ctrl_page.enabled = 1; + commpage_update_kdebug_state(); + } else { + kdebug_enable &= ~(KDEBUG_ENABLE_TRACE | KDEBUG_ENABLE_PPT); + kd_ctrl_page.kdebug_slowcheck |= SLOW_NOLOG; + kd_ctrl_page.enabled = 0; + commpage_update_kdebug_state(); + } + lck_spin_unlock(kds_spin_lock); + ml_set_interrupts_enabled(s); - if (kdebug_flags & KDBG_RANGECHECK) - { - if ((debugid < kdlog_beg) - || ((debugid >= kdlog_end) && (debugid >> 24 != DBG_TRACE))) - goto out; - } - else if (kdebug_flags & KDBG_VALCHECK) - { - if ((debugid & DBG_FUNC_MASK) != kdlog_value1 && - (debugid & DBG_FUNC_MASK) != kdlog_value2 && - (debugid & DBG_FUNC_MASK) != kdlog_value3 && - (debugid & DBG_FUNC_MASK) != kdlog_value4 && - (debugid >> 24 != DBG_TRACE)) - goto out; - } + if (enabled) { + kdbg_iop_list_callback(kd_ctrl_page.kdebug_iops, + KD_CALLBACK_KDEBUG_ENABLED, NULL); + } else { + kdbg_iop_list_callback(kd_ctrl_page.kdebug_iops, + KD_CALLBACK_KDEBUG_DISABLED, NULL); + } +} -record_trace: - kd = kdbip[cpu].kd_bufptr; - kd->debugid = debugid; - kd->arg1 = arg1; - kd->arg2 = arg2; - kd->arg3 = arg3; - kd->arg4 = arg4; - kd->arg5 = arg5; - - /* - * Watch for out of order timestamps - */ - if (now < kdbip[cpu].kd_prev_timebase) - { - /* - * if so, just store the previous timestamp + a cycle - */ - now = ++kdbip[cpu].kd_prev_timebase & KDBG_TIMESTAMP_MASK; - } - else - { - kdbip[cpu].kd_prev_timebase = now; - } - kd->timestamp = now | (((uint64_t)cpu) << KDBG_CPU_SHIFT); - - kdbip[cpu].kd_bufptr++; - - if (kdbip[cpu].kd_bufptr >= kdbip[cpu].kd_buflast) - kdbip[cpu].kd_bufptr = kdbip[cpu].kd_buffer; - - if (kdbip[cpu].kd_bufptr == kdbip[cpu].kd_readlast) { - if (kdebug_flags & KDBG_NOWRAP) - kdebug_slowcheck |= SLOW_NOLOG; - kdbip[cpu].kd_wrapped = 1; - kdebug_flags |= KDBG_WRAPPED; +static void +kdbg_set_flags(int slowflag, int enableflag, bool enabled) +{ + int s = ml_set_interrupts_enabled(false); + lck_spin_lock_grp(kds_spin_lock, kdebug_lck_grp); + + if (enabled) { + kd_ctrl_page.kdebug_slowcheck |= slowflag; + kdebug_enable |= enableflag; + } else { + kd_ctrl_page.kdebug_slowcheck &= ~slowflag; + kdebug_enable &= ~enableflag; } -out: + lck_spin_unlock(kds_spin_lock); ml_set_interrupts_enabled(s); } -void -kernel_debug(unsigned int debugid, unsigned int arg1, unsigned int arg2, unsigned int arg3, - unsigned int arg4, __unused unsigned int arg5) +/* + * Disable wrapping and return true if trace wrapped, false otherwise. + */ +static bool +disable_wrap(uint32_t *old_slowcheck, uint32_t *old_flags) { - kernel_debug_internal(debugid, arg1, arg2, arg3, arg4, (int)current_thread(), 1); -} + bool wrapped; + int s = ml_set_interrupts_enabled(false); + lck_spin_lock_grp(kds_spin_lock, kdebug_lck_grp); -void -kernel_debug1(unsigned int debugid, unsigned int arg1, unsigned int arg2, unsigned int arg3, - unsigned int arg4, unsigned int arg5) -{ - kernel_debug_internal(debugid, arg1, arg2, arg3, arg4, arg5, 0); + *old_slowcheck = kd_ctrl_page.kdebug_slowcheck; + *old_flags = kd_ctrl_page.kdebug_flags; + + wrapped = kd_ctrl_page.kdebug_flags & KDBG_WRAPPED; + kd_ctrl_page.kdebug_flags &= ~KDBG_WRAPPED; + kd_ctrl_page.kdebug_flags |= KDBG_NOWRAP; + + lck_spin_unlock(kds_spin_lock); + ml_set_interrupts_enabled(s); + + return wrapped; } static void -kdbg_lock_init(void) +enable_wrap(uint32_t old_slowcheck) { - host_basic_info_data_t hinfo; - mach_msg_type_number_t count = HOST_BASIC_INFO_COUNT; + int s = ml_set_interrupts_enabled(false); + lck_spin_lock_grp(kds_spin_lock, kdebug_lck_grp); - if (kdebug_flags & KDBG_LOCKINIT) - return; + kd_ctrl_page.kdebug_flags &= ~KDBG_NOWRAP; + + if (!(old_slowcheck & SLOW_NOLOG)) { + kd_ctrl_page.kdebug_slowcheck &= ~SLOW_NOLOG; + } - /* get the number of cpus and cache it */ -#define BSD_HOST 1 - host_info((host_t)BSD_HOST, HOST_BASIC_INFO, (host_info_t)&hinfo, &count); - kd_cpus = hinfo.logical_cpu_max; + lck_spin_unlock(kds_spin_lock); + ml_set_interrupts_enabled(s); +} - if (kmem_alloc(kernel_map, (unsigned int *)&kdbip, - sizeof(struct kd_bufinfo) * kd_cpus) != KERN_SUCCESS) - return; +static int +create_buffers(bool early_trace) +{ + unsigned int i; + unsigned int p_buffer_size; + unsigned int f_buffer_size; + unsigned int f_buffers; + int error = 0; /* - * allocate lock group attribute and group + * For the duration of this allocation, trace code will only reference + * kdebug_iops. Any iops registered after this enabling will not be + * messaged until the buffers are reallocated. + * + * TLDR; Must read kd_iops once and only once! */ - kd_trace_mtx_sysctl_grp_attr = lck_grp_attr_alloc_init(); - kd_trace_mtx_sysctl_grp = lck_grp_alloc_init("kdebug", kd_trace_mtx_sysctl_grp_attr); - - /* - * allocate the lock attribute - */ - kd_trace_mtx_sysctl_attr = lck_attr_alloc_init(); + kd_ctrl_page.kdebug_iops = kd_iops; +#if CONFIG_EMBEDDED + assert(kdbg_iop_list_is_valid(kd_ctrl_page.kdebug_iops)); +#endif /* - * allocate and initialize spin lock and mutex + * If the list is valid, it is sorted, newest -> oldest. Each iop entry + * has a cpu_id of "the older entry + 1", so the highest cpu_id will + * be the list head + 1. */ - kd_trace_mtx_sysctl = lck_mtx_alloc_init(kd_trace_mtx_sysctl_grp, kd_trace_mtx_sysctl_attr); - kdebug_flags |= KDBG_LOCKINIT; -} + kd_ctrl_page.kdebug_cpus = kd_ctrl_page.kdebug_iops ? kd_ctrl_page.kdebug_iops->cpu_id + 1 : kdbg_cpu_count(early_trace); + if (kmem_alloc(kernel_map, (vm_offset_t *)&kdbip, sizeof(struct kd_bufinfo) * kd_ctrl_page.kdebug_cpus, VM_KERN_MEMORY_DIAG) != KERN_SUCCESS) { + error = ENOSPC; + goto out; + } -int -kdbg_bootstrap(void) -{ - kdebug_flags &= ~KDBG_WRAPPED; + if (nkdbufs < (kd_ctrl_page.kdebug_cpus * EVENTS_PER_STORAGE_UNIT * MIN_STORAGE_UNITS_PER_CPU)) { + n_storage_units = kd_ctrl_page.kdebug_cpus * MIN_STORAGE_UNITS_PER_CPU; + } else { + n_storage_units = nkdbufs / EVENTS_PER_STORAGE_UNIT; + } - return (create_buffers()); -} + nkdbufs = n_storage_units * EVENTS_PER_STORAGE_UNIT; -int -kdbg_reinit(void) -{ - int ret=0; + f_buffers = n_storage_units / N_STORAGE_UNITS_PER_BUFFER; + n_storage_buffers = f_buffers; - /* - * Disable trace collecting - * First make sure we're not in - * the middle of cutting a trace - */ + f_buffer_size = N_STORAGE_UNITS_PER_BUFFER * sizeof(struct kd_storage); + p_buffer_size = (n_storage_units % N_STORAGE_UNITS_PER_BUFFER) * sizeof(struct kd_storage); - kdebug_enable &= ~KDEBUG_ENABLE_TRACE; - kdebug_slowcheck |= SLOW_NOLOG; + if (p_buffer_size) { + n_storage_buffers++; + } - /* - * make sure the SLOW_NOLOG is seen - * by everyone that might be trying - * to cut a trace.. - */ - IOSleep(100); + kd_bufs = NULL; - delete_buffers(); + if (kdcopybuf == 0) { + if (kmem_alloc(kernel_map, (vm_offset_t *)&kdcopybuf, (vm_size_t)KDCOPYBUF_SIZE, VM_KERN_MEMORY_DIAG) != KERN_SUCCESS) { + error = ENOSPC; + goto out; + } + } + if (kmem_alloc(kernel_map, (vm_offset_t *)&kd_bufs, (vm_size_t)(n_storage_buffers * sizeof(struct kd_storage_buffers)), VM_KERN_MEMORY_DIAG) != KERN_SUCCESS) { + error = ENOSPC; + goto out; + } + bzero(kd_bufs, n_storage_buffers * sizeof(struct kd_storage_buffers)); - if ((kdebug_flags & KDBG_MAPINIT) && kd_mapsize && kd_mapptr) - { - kmem_free(kernel_map, (vm_offset_t)kd_mapptr, kd_mapsize); - kdebug_flags &= ~KDBG_MAPINIT; - kd_mapsize = 0; - kd_mapptr = (kd_threadmap *) 0; - kd_mapcount = 0; - } + for (i = 0; i < f_buffers; i++) { + if (kmem_alloc(kernel_map, (vm_offset_t *)&kd_bufs[i].kdsb_addr, (vm_size_t)f_buffer_size, VM_KERN_MEMORY_DIAG) != KERN_SUCCESS) { + error = ENOSPC; + goto out; + } + bzero(kd_bufs[i].kdsb_addr, f_buffer_size); - ret = kdbg_bootstrap(); + kd_bufs[i].kdsb_size = f_buffer_size; + } + if (p_buffer_size) { + if (kmem_alloc(kernel_map, (vm_offset_t *)&kd_bufs[i].kdsb_addr, (vm_size_t)p_buffer_size, VM_KERN_MEMORY_DIAG) != KERN_SUCCESS) { + error = ENOSPC; + goto out; + } + bzero(kd_bufs[i].kdsb_addr, p_buffer_size); - return(ret); -} + kd_bufs[i].kdsb_size = p_buffer_size; + } + n_storage_units = 0; -void -kdbg_trace_data(struct proc *proc, long *arg_pid) -{ - if (!proc) - *arg_pid = 0; - else - *arg_pid = proc->p_pid; - - return; -} + for (i = 0; i < n_storage_buffers; i++) { + struct kd_storage *kds; + int n_elements; + int n; + n_elements = kd_bufs[i].kdsb_size / sizeof(struct kd_storage); + kds = kd_bufs[i].kdsb_addr; -void -kdbg_trace_string(struct proc *proc, long *arg1, long *arg2, long *arg3, long *arg4) -{ - char *dbg_nameptr; - int dbg_namelen; - long dbg_parms[4]; - if (!proc) - { - *arg1 = 0; - *arg2 = 0; - *arg3 = 0; - *arg4 = 0; - return; - } - - /* Collect the pathname for tracing */ - dbg_nameptr = proc->p_comm; - dbg_namelen = strlen(proc->p_comm); - dbg_parms[0]=0L; - dbg_parms[1]=0L; - dbg_parms[2]=0L; - dbg_parms[3]=0L; - - if(dbg_namelen > (int)sizeof(dbg_parms)) - dbg_namelen = sizeof(dbg_parms); - - strncpy((char *)dbg_parms, dbg_nameptr, dbg_namelen); - - *arg1=dbg_parms[0]; - *arg2=dbg_parms[1]; - *arg3=dbg_parms[2]; - *arg4=dbg_parms[3]; -} + for (n = 0; n < n_elements; n++) { + kds[n].kds_next.buffer_index = kd_ctrl_page.kds_free_list.buffer_index; + kds[n].kds_next.offset = kd_ctrl_page.kds_free_list.offset; -static void -kdbg_resolve_map(thread_t th_act, void *opaque) -{ - kd_threadmap *mapptr; - krt_t *t = (krt_t *)opaque; + kd_ctrl_page.kds_free_list.buffer_index = i; + kd_ctrl_page.kds_free_list.offset = n; + } + n_storage_units += n_elements; + } - if(t->count < t->maxcount) - { - mapptr=&t->map[t->count]; - mapptr->thread = (unsigned int)th_act; - (void) strlcpy (mapptr->command, t->atts->task_comm, - sizeof(t->atts->task_comm)); + bzero((char *)kdbip, sizeof(struct kd_bufinfo) * kd_ctrl_page.kdebug_cpus); - /* - Some kernel threads have no associated pid. - We still need to mark the entry as valid. - */ - if (t->atts->pid) - mapptr->valid = t->atts->pid; - else - mapptr->valid = 1; + for (i = 0; i < kd_ctrl_page.kdebug_cpus; i++) { + kdbip[i].kd_list_head.raw = KDS_PTR_NULL; + kdbip[i].kd_list_tail.raw = KDS_PTR_NULL; + kdbip[i].kd_lostevents = false; + kdbip[i].num_bufs = 0; + } - t->count++; - } + kd_ctrl_page.kdebug_flags |= KDBG_BUFINIT; + + kd_ctrl_page.kds_inuse_count = 0; + n_storage_threshold = n_storage_units / 2; +out: + if (error) { + delete_buffers(); + } + + return error; +} + +static void +delete_buffers(void) +{ + unsigned int i; + + if (kd_bufs) { + for (i = 0; i < n_storage_buffers; i++) { + if (kd_bufs[i].kdsb_addr) { + kmem_free(kernel_map, (vm_offset_t)kd_bufs[i].kdsb_addr, (vm_size_t)kd_bufs[i].kdsb_size); + } + } + kmem_free(kernel_map, (vm_offset_t)kd_bufs, (vm_size_t)(n_storage_buffers * sizeof(struct kd_storage_buffers))); + + kd_bufs = NULL; + n_storage_buffers = 0; + } + if (kdcopybuf) { + kmem_free(kernel_map, (vm_offset_t)kdcopybuf, KDCOPYBUF_SIZE); + + kdcopybuf = NULL; + } + kd_ctrl_page.kds_free_list.raw = KDS_PTR_NULL; + + if (kdbip) { + kmem_free(kernel_map, (vm_offset_t)kdbip, sizeof(struct kd_bufinfo) * kd_ctrl_page.kdebug_cpus); + + kdbip = NULL; + } + kd_ctrl_page.kdebug_iops = NULL; + kd_ctrl_page.kdebug_cpus = 0; + kd_ctrl_page.kdebug_flags &= ~KDBG_BUFINIT; +} + +void +release_storage_unit(int cpu, uint32_t kdsp_raw) +{ + int s = 0; + struct kd_storage *kdsp_actual; + struct kd_bufinfo *kdbp; + union kds_ptr kdsp; + + kdsp.raw = kdsp_raw; + + s = ml_set_interrupts_enabled(false); + lck_spin_lock_grp(kds_spin_lock, kdebug_lck_grp); + + kdbp = &kdbip[cpu]; + + if (kdsp.raw == kdbp->kd_list_head.raw) { + /* + * it's possible for the storage unit pointed to + * by kdsp to have already been stolen... so + * check to see if it's still the head of the list + * now that we're behind the lock that protects + * adding and removing from the queue... + * since we only ever release and steal units from + * that position, if it's no longer the head + * we having nothing to do in this context + */ + kdsp_actual = POINTER_FROM_KDS_PTR(kdsp); + kdbp->kd_list_head = kdsp_actual->kds_next; + + kdsp_actual->kds_next = kd_ctrl_page.kds_free_list; + kd_ctrl_page.kds_free_list = kdsp; + + kd_ctrl_page.kds_inuse_count--; + } + lck_spin_unlock(kds_spin_lock); + ml_set_interrupts_enabled(s); +} + +bool +allocate_storage_unit(int cpu) +{ + union kds_ptr kdsp; + struct kd_storage *kdsp_actual, *kdsp_next_actual; + struct kd_bufinfo *kdbp, *kdbp_vict, *kdbp_try; + uint64_t oldest_ts, ts; + bool retval = true; + int s = 0; + + s = ml_set_interrupts_enabled(false); + lck_spin_lock_grp(kds_spin_lock, kdebug_lck_grp); + + kdbp = &kdbip[cpu]; + + /* If someone beat us to the allocate, return success */ + if (kdbp->kd_list_tail.raw != KDS_PTR_NULL) { + kdsp_actual = POINTER_FROM_KDS_PTR(kdbp->kd_list_tail); + + if (kdsp_actual->kds_bufindx < EVENTS_PER_STORAGE_UNIT) { + goto out; + } + } + + if ((kdsp = kd_ctrl_page.kds_free_list).raw != KDS_PTR_NULL) { + /* + * If there's a free page, grab it from the free list. + */ + kdsp_actual = POINTER_FROM_KDS_PTR(kdsp); + kd_ctrl_page.kds_free_list = kdsp_actual->kds_next; + + kd_ctrl_page.kds_inuse_count++; + } else { + /* + * Otherwise, we're going to lose events and repurpose the oldest + * storage unit we can find. + */ + if (kd_ctrl_page.kdebug_flags & KDBG_NOWRAP) { + kd_ctrl_page.kdebug_slowcheck |= SLOW_NOLOG; + kdbp->kd_lostevents = true; + retval = false; + goto out; + } + kdbp_vict = NULL; + oldest_ts = UINT64_MAX; + + for (kdbp_try = &kdbip[0]; kdbp_try < &kdbip[kd_ctrl_page.kdebug_cpus]; kdbp_try++) { + if (kdbp_try->kd_list_head.raw == KDS_PTR_NULL) { + /* + * no storage unit to steal + */ + continue; + } + + kdsp_actual = POINTER_FROM_KDS_PTR(kdbp_try->kd_list_head); + + if (kdsp_actual->kds_bufcnt < EVENTS_PER_STORAGE_UNIT) { + /* + * make sure we don't steal the storage unit + * being actively recorded to... need to + * move on because we don't want an out-of-order + * set of events showing up later + */ + continue; + } + + /* + * When wrapping, steal the storage unit with the + * earliest timestamp on its last event, instead of the + * earliest timestamp on the first event. This allows a + * storage unit with more recent events to be preserved, + * even if the storage unit contains events that are + * older than those found in other CPUs. + */ + ts = kdbg_get_timestamp(&kdsp_actual->kds_records[EVENTS_PER_STORAGE_UNIT - 1]); + if (ts < oldest_ts) { + oldest_ts = ts; + kdbp_vict = kdbp_try; + } + } + if (kdbp_vict == NULL) { + kdebug_enable = 0; + kd_ctrl_page.enabled = 0; + commpage_update_kdebug_state(); + retval = false; + goto out; + } + kdsp = kdbp_vict->kd_list_head; + kdsp_actual = POINTER_FROM_KDS_PTR(kdsp); + kdbp_vict->kd_list_head = kdsp_actual->kds_next; + + if (kdbp_vict->kd_list_head.raw != KDS_PTR_NULL) { + kdsp_next_actual = POINTER_FROM_KDS_PTR(kdbp_vict->kd_list_head); + kdsp_next_actual->kds_lostevents = true; + } else { + kdbp_vict->kd_lostevents = true; + } + + if (kd_ctrl_page.oldest_time < oldest_ts) { + kd_ctrl_page.oldest_time = oldest_ts; + } + kd_ctrl_page.kdebug_flags |= KDBG_WRAPPED; + } + kdsp_actual->kds_timestamp = kdbg_timestamp(); + kdsp_actual->kds_next.raw = KDS_PTR_NULL; + kdsp_actual->kds_bufcnt = 0; + kdsp_actual->kds_readlast = 0; + + kdsp_actual->kds_lostevents = kdbp->kd_lostevents; + kdbp->kd_lostevents = false; + kdsp_actual->kds_bufindx = 0; + + if (kdbp->kd_list_head.raw == KDS_PTR_NULL) { + kdbp->kd_list_head = kdsp; + } else { + POINTER_FROM_KDS_PTR(kdbp->kd_list_tail)->kds_next = kdsp; + } + kdbp->kd_list_tail = kdsp; +out: + lck_spin_unlock(kds_spin_lock); + ml_set_interrupts_enabled(s); + + return retval; +} + +int +kernel_debug_register_callback(kd_callback_t callback) +{ + kd_iop_t* iop; + if (kmem_alloc(kernel_map, (vm_offset_t *)&iop, sizeof(kd_iop_t), VM_KERN_MEMORY_DIAG) == KERN_SUCCESS) { + memcpy(&iop->callback, &callback, sizeof(kd_callback_t)); + + /* + * Some IOP clients are not providing a name. + * + * Remove when fixed. + */ + { + bool is_valid_name = false; + for (uint32_t length = 0; length < sizeof(callback.iop_name); ++length) { + /* This is roughly isprintable(c) */ + if (callback.iop_name[length] > 0x20 && callback.iop_name[length] < 0x7F) { + continue; + } + if (callback.iop_name[length] == 0) { + if (length) { + is_valid_name = true; + } + break; + } + } + + if (!is_valid_name) { + strlcpy(iop->callback.iop_name, "IOP-???", sizeof(iop->callback.iop_name)); + } + } + + iop->last_timestamp = 0; + + do { + /* + * We use two pieces of state, the old list head + * pointer, and the value of old_list_head->cpu_id. + * If we read kd_iops more than once, it can change + * between reads. + * + * TLDR; Must not read kd_iops more than once per loop. + */ + iop->next = kd_iops; + iop->cpu_id = iop->next ? (iop->next->cpu_id + 1) : kdbg_cpu_count(false); + + /* + * Header says OSCompareAndSwapPtr has a memory barrier + */ + } while (!OSCompareAndSwapPtr(iop->next, iop, (void* volatile*)&kd_iops)); + + return iop->cpu_id; + } + + return 0; +} + +void +kernel_debug_enter( + uint32_t coreid, + uint32_t debugid, + uint64_t timestamp, + uintptr_t arg1, + uintptr_t arg2, + uintptr_t arg3, + uintptr_t arg4, + uintptr_t threadid + ) +{ + uint32_t bindx; + kd_buf *kd; + struct kd_bufinfo *kdbp; + struct kd_storage *kdsp_actual; + union kds_ptr kds_raw; + + if (kd_ctrl_page.kdebug_slowcheck) { + if ((kd_ctrl_page.kdebug_slowcheck & SLOW_NOLOG) || !(kdebug_enable & (KDEBUG_ENABLE_TRACE | KDEBUG_ENABLE_PPT))) { + goto out1; + } + + if (kd_ctrl_page.kdebug_flags & KDBG_TYPEFILTER_CHECK) { + if (typefilter_is_debugid_allowed(kdbg_typefilter, debugid)) { + goto record_event; + } + goto out1; + } else if (kd_ctrl_page.kdebug_flags & KDBG_RANGECHECK) { + if (debugid >= kdlog_beg && debugid <= kdlog_end) { + goto record_event; + } + goto out1; + } else if (kd_ctrl_page.kdebug_flags & KDBG_VALCHECK) { + if ((debugid & KDBG_EVENTID_MASK) != kdlog_value1 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value2 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value3 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value4) { + goto out1; + } + } + } + +record_event: + if (timestamp < kd_ctrl_page.oldest_time) { + goto out1; + } + +#if CONFIG_EMBEDDED + /* + * When start_kern_tracing is called by the kernel to trace very + * early kernel events, it saves data to a secondary buffer until + * it is possible to initialize ktrace, and then dumps the events + * into the ktrace buffer using this method. In this case, iops will + * be NULL, and the coreid will be zero. It is not possible to have + * a valid IOP coreid of zero, so pass if both iops is NULL and coreid + * is zero. + */ + assert(kdbg_iop_list_contains_cpu_id(kd_ctrl_page.kdebug_iops, coreid) || (kd_ctrl_page.kdebug_iops == NULL && coreid == 0)); +#endif + + disable_preemption(); + + if (kd_ctrl_page.enabled == 0) { + goto out; + } + + kdbp = &kdbip[coreid]; + timestamp &= KDBG_TIMESTAMP_MASK; + +#if KDEBUG_MOJO_TRACE + if (kdebug_enable & KDEBUG_ENABLE_SERIAL) { + kdebug_serial_print(coreid, debugid, timestamp, + arg1, arg2, arg3, arg4, threadid); + } +#endif + +retry_q: + kds_raw = kdbp->kd_list_tail; + + if (kds_raw.raw != KDS_PTR_NULL) { + kdsp_actual = POINTER_FROM_KDS_PTR(kds_raw); + bindx = kdsp_actual->kds_bufindx; + } else { + kdsp_actual = NULL; + bindx = EVENTS_PER_STORAGE_UNIT; + } + + if (kdsp_actual == NULL || bindx >= EVENTS_PER_STORAGE_UNIT) { + if (allocate_storage_unit(coreid) == false) { + /* + * this can only happen if wrapping + * has been disabled + */ + goto out; + } + goto retry_q; + } + if (!OSCompareAndSwap(bindx, bindx + 1, &kdsp_actual->kds_bufindx)) { + goto retry_q; + } + + // IOP entries can be allocated before xnu allocates and inits the buffer + if (timestamp < kdsp_actual->kds_timestamp) { + kdsp_actual->kds_timestamp = timestamp; + } + + kd = &kdsp_actual->kds_records[bindx]; + + kd->debugid = debugid; + kd->arg1 = arg1; + kd->arg2 = arg2; + kd->arg3 = arg3; + kd->arg4 = arg4; + kd->arg5 = threadid; + + kdbg_set_timestamp_and_cpu(kd, timestamp, coreid); + + OSAddAtomic(1, &kdsp_actual->kds_bufcnt); +out: + enable_preemption(); +out1: + if ((kds_waiter && kd_ctrl_page.kds_inuse_count >= n_storage_threshold)) { + kdbg_wakeup(); + } +} + +/* + * Check if the given debug ID is allowed to be traced on the current process. + * + * Returns true if allowed and false otherwise. + */ +static inline bool +kdebug_debugid_procfilt_allowed(uint32_t debugid) +{ + uint32_t procfilt_flags = kd_ctrl_page.kdebug_flags & + (KDBG_PIDCHECK | KDBG_PIDEXCLUDE); + + if (!procfilt_flags) { + return true; + } + + /* + * DBG_TRACE and MACH_SCHED tracepoints ignore the process filter. + */ + if ((debugid & 0xffff0000) == MACHDBG_CODE(DBG_MACH_SCHED, 0) || + (debugid >> 24 == DBG_TRACE)) { + return true; + } + + struct proc *curproc = current_proc(); + /* + * If the process is missing (early in boot), allow it. + */ + if (!curproc) { + return true; + } + + if (procfilt_flags & KDBG_PIDCHECK) { + /* + * Allow only processes marked with the kdebug bit. + */ + return curproc->p_kdebug; + } else if (procfilt_flags & KDBG_PIDEXCLUDE) { + /* + * Exclude any process marked with the kdebug bit. + */ + return !curproc->p_kdebug; + } else { + panic("kdebug: invalid procfilt flags %x", kd_ctrl_page.kdebug_flags); + __builtin_unreachable(); + } +} + +static void +kernel_debug_internal( + uint32_t debugid, + uintptr_t arg1, + uintptr_t arg2, + uintptr_t arg3, + uintptr_t arg4, + uintptr_t arg5, + uint64_t flags) +{ + uint64_t now; + uint32_t bindx; + kd_buf *kd; + int cpu; + struct kd_bufinfo *kdbp; + struct kd_storage *kdsp_actual; + union kds_ptr kds_raw; + bool only_filter = flags & KDBG_FLAG_FILTERED; + bool observe_procfilt = !(flags & KDBG_FLAG_NOPROCFILT); + + if (kd_ctrl_page.kdebug_slowcheck) { + if ((kd_ctrl_page.kdebug_slowcheck & SLOW_NOLOG) || + !(kdebug_enable & (KDEBUG_ENABLE_TRACE | KDEBUG_ENABLE_PPT))) { + goto out1; + } + + if (!ml_at_interrupt_context() && observe_procfilt && + !kdebug_debugid_procfilt_allowed(debugid)) { + goto out1; + } + + if (kd_ctrl_page.kdebug_flags & KDBG_TYPEFILTER_CHECK) { + if (typefilter_is_debugid_allowed(kdbg_typefilter, debugid)) { + goto record_event; + } + + goto out1; + } else if (only_filter) { + goto out1; + } else if (kd_ctrl_page.kdebug_flags & KDBG_RANGECHECK) { + /* Always record trace system info */ + if (KDBG_EXTRACT_CLASS(debugid) == DBG_TRACE) { + goto record_event; + } + + if (debugid < kdlog_beg || debugid > kdlog_end) { + goto out1; + } + } else if (kd_ctrl_page.kdebug_flags & KDBG_VALCHECK) { + /* Always record trace system info */ + if (KDBG_EXTRACT_CLASS(debugid) == DBG_TRACE) { + goto record_event; + } + + if ((debugid & KDBG_EVENTID_MASK) != kdlog_value1 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value2 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value3 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value4) { + goto out1; + } + } + } else if (only_filter) { + goto out1; + } + +record_event: + disable_preemption(); + + if (kd_ctrl_page.enabled == 0) { + goto out; + } + + cpu = cpu_number(); + kdbp = &kdbip[cpu]; + +#if KDEBUG_MOJO_TRACE + if (kdebug_enable & KDEBUG_ENABLE_SERIAL) { + kdebug_serial_print(cpu, debugid, + kdbg_timestamp() & KDBG_TIMESTAMP_MASK, + arg1, arg2, arg3, arg4, arg5); + } +#endif + +retry_q: + kds_raw = kdbp->kd_list_tail; + + if (kds_raw.raw != KDS_PTR_NULL) { + kdsp_actual = POINTER_FROM_KDS_PTR(kds_raw); + bindx = kdsp_actual->kds_bufindx; + } else { + kdsp_actual = NULL; + bindx = EVENTS_PER_STORAGE_UNIT; + } + + if (kdsp_actual == NULL || bindx >= EVENTS_PER_STORAGE_UNIT) { + if (allocate_storage_unit(cpu) == false) { + /* + * this can only happen if wrapping + * has been disabled + */ + goto out; + } + goto retry_q; + } + + now = kdbg_timestamp() & KDBG_TIMESTAMP_MASK; + + if (!OSCompareAndSwap(bindx, bindx + 1, &kdsp_actual->kds_bufindx)) { + goto retry_q; + } + + kd = &kdsp_actual->kds_records[bindx]; + + kd->debugid = debugid; + kd->arg1 = arg1; + kd->arg2 = arg2; + kd->arg3 = arg3; + kd->arg4 = arg4; + kd->arg5 = arg5; + + kdbg_set_timestamp_and_cpu(kd, now, cpu); + + OSAddAtomic(1, &kdsp_actual->kds_bufcnt); + +#if KPERF + kperf_kdebug_callback(debugid, __builtin_frame_address(0)); +#endif +out: + enable_preemption(); +out1: + if (kds_waiter && kd_ctrl_page.kds_inuse_count >= n_storage_threshold) { + uint32_t etype; + uint32_t stype; + + etype = debugid & KDBG_EVENTID_MASK; + stype = debugid & KDBG_CSC_MASK; + + if (etype == INTERRUPT || etype == MACH_vmfault || + stype == BSC_SysCall || stype == MACH_SysCall) { + kdbg_wakeup(); + } + } +} + +__attribute__((noinline)) +void +kernel_debug( + uint32_t debugid, + uintptr_t arg1, + uintptr_t arg2, + uintptr_t arg3, + uintptr_t arg4, + __unused uintptr_t arg5) +{ + kernel_debug_internal(debugid, arg1, arg2, arg3, arg4, + (uintptr_t)thread_tid(current_thread()), 0); +} + +__attribute__((noinline)) +void +kernel_debug1( + uint32_t debugid, + uintptr_t arg1, + uintptr_t arg2, + uintptr_t arg3, + uintptr_t arg4, + uintptr_t arg5) +{ + kernel_debug_internal(debugid, arg1, arg2, arg3, arg4, arg5, 0); +} + +__attribute__((noinline)) +void +kernel_debug_flags( + uint32_t debugid, + uintptr_t arg1, + uintptr_t arg2, + uintptr_t arg3, + uintptr_t arg4, + uint64_t flags) +{ + kernel_debug_internal(debugid, arg1, arg2, arg3, arg4, + (uintptr_t)thread_tid(current_thread()), flags); +} + +__attribute__((noinline)) +void +kernel_debug_filtered( + uint32_t debugid, + uintptr_t arg1, + uintptr_t arg2, + uintptr_t arg3, + uintptr_t arg4) +{ + kernel_debug_flags(debugid, arg1, arg2, arg3, arg4, KDBG_FLAG_FILTERED); +} + +void +kernel_debug_string_early(const char *message) +{ + uintptr_t arg[4] = {0, 0, 0, 0}; + + /* Stuff the message string in the args and log it. */ + strncpy((char *)arg, message, MIN(sizeof(arg), strlen(message))); + KERNEL_DEBUG_EARLY( + TRACE_INFO_STRING, + arg[0], arg[1], arg[2], arg[3]); +} + +#define SIMPLE_STR_LEN (64) +static_assert(SIMPLE_STR_LEN % sizeof(uintptr_t) == 0); + +void +kernel_debug_string_simple(uint32_t eventid, const char *str) +{ + if (!kdebug_enable) { + return; + } + + /* array of uintptr_ts simplifies emitting the string as arguments */ + uintptr_t str_buf[(SIMPLE_STR_LEN / sizeof(uintptr_t)) + 1] = { 0 }; + size_t len = strlcpy((char *)str_buf, str, SIMPLE_STR_LEN + 1); + + uintptr_t thread_id = (uintptr_t)thread_tid(current_thread()); + uint32_t debugid = eventid | DBG_FUNC_START; + + /* string can fit in a single tracepoint */ + if (len <= (4 * sizeof(uintptr_t))) { + debugid |= DBG_FUNC_END; + } + + kernel_debug_internal(debugid, str_buf[0], + str_buf[1], + str_buf[2], + str_buf[3], thread_id, 0); + + debugid &= KDBG_EVENTID_MASK; + int i = 4; + size_t written = 4 * sizeof(uintptr_t); + + for (; written < len; i += 4, written += 4 * sizeof(uintptr_t)) { + /* if this is the last tracepoint to be emitted */ + if ((written + (4 * sizeof(uintptr_t))) >= len) { + debugid |= DBG_FUNC_END; + } + kernel_debug_internal(debugid, str_buf[i], + str_buf[i + 1], + str_buf[i + 2], + str_buf[i + 3], thread_id, 0); + } +} + +extern int master_cpu; /* MACH_KERNEL_PRIVATE */ +/* + * Used prior to start_kern_tracing() being called. + * Log temporarily into a static buffer. + */ +void +kernel_debug_early( + uint32_t debugid, + uintptr_t arg1, + uintptr_t arg2, + uintptr_t arg3, + uintptr_t arg4) +{ +#if defined(__x86_64__) + extern int early_boot; + /* + * Note that "early" isn't early enough in some cases where + * we're invoked before gsbase is set on x86, hence the + * check of "early_boot". + */ + if (early_boot) { + return; + } +#endif + + /* If early tracing is over, use the normal path. */ + if (kd_early_done) { + KERNEL_DEBUG_CONSTANT(debugid, arg1, arg2, arg3, arg4, 0); + return; + } + + /* Do nothing if the buffer is full or we're not on the boot cpu. */ + kd_early_overflow = kd_early_index >= KD_EARLY_BUFFER_NBUFS; + if (kd_early_overflow || cpu_number() != master_cpu) { + return; + } + + kd_early_buffer[kd_early_index].debugid = debugid; + kd_early_buffer[kd_early_index].timestamp = mach_absolute_time(); + kd_early_buffer[kd_early_index].arg1 = arg1; + kd_early_buffer[kd_early_index].arg2 = arg2; + kd_early_buffer[kd_early_index].arg3 = arg3; + kd_early_buffer[kd_early_index].arg4 = arg4; + kd_early_buffer[kd_early_index].arg5 = 0; + kd_early_index++; +} + +/* + * Transfer the contents of the temporary buffer into the trace buffers. + * Precede that by logging the rebase time (offset) - the TSC-based time (in ns) + * when mach_absolute_time is set to 0. + */ +static void +kernel_debug_early_end(void) +{ + if (cpu_number() != master_cpu) { + panic("kernel_debug_early_end() not call on boot processor"); + } + + /* reset the current oldest time to allow early events */ + kd_ctrl_page.oldest_time = 0; + +#if !CONFIG_EMBEDDED + /* Fake sentinel marking the start of kernel time relative to TSC */ + kernel_debug_enter(0, + TRACE_TIMESTAMPS, + 0, + (uint32_t)(tsc_rebase_abs_time >> 32), + (uint32_t)tsc_rebase_abs_time, + tsc_at_boot, + 0, + 0); +#endif + for (unsigned int i = 0; i < kd_early_index; i++) { + kernel_debug_enter(0, + kd_early_buffer[i].debugid, + kd_early_buffer[i].timestamp, + kd_early_buffer[i].arg1, + kd_early_buffer[i].arg2, + kd_early_buffer[i].arg3, + kd_early_buffer[i].arg4, + 0); + } + + /* Cut events-lost event on overflow */ + if (kd_early_overflow) { + KDBG_RELEASE(TRACE_LOST_EVENTS, 1); + } + + kd_early_done = true; + + /* This trace marks the start of kernel tracing */ + kernel_debug_string_early("early trace done"); +} + +void +kernel_debug_disable(void) +{ + if (kdebug_enable) { + kdbg_set_tracing_enabled(false, 0); + } +} + +/* + * Returns non-zero if debugid is in a reserved class. + */ +static int +kdebug_validate_debugid(uint32_t debugid) +{ + uint8_t debugid_class; + + debugid_class = KDBG_EXTRACT_CLASS(debugid); + switch (debugid_class) { + case DBG_TRACE: + return EPERM; + } + + return 0; +} + +/* + * Support syscall SYS_kdebug_typefilter. + */ +int +kdebug_typefilter(__unused struct proc* p, + struct kdebug_typefilter_args* uap, + __unused int *retval) +{ + int ret = KERN_SUCCESS; + + if (uap->addr == USER_ADDR_NULL || + uap->size == USER_ADDR_NULL) { + return EINVAL; + } + + /* + * The atomic load is to close a race window with setting the typefilter + * and memory entry values. A description follows: + * + * Thread 1 (writer) + * + * Allocate Typefilter + * Allocate MemoryEntry + * Write Global MemoryEntry Ptr + * Atomic Store (Release) Global Typefilter Ptr + * + * Thread 2 (reader, AKA us) + * + * if ((Atomic Load (Acquire) Global Typefilter Ptr) == NULL) + * return; + * + * Without the atomic store, it isn't guaranteed that the write of + * Global MemoryEntry Ptr is visible before we can see the write of + * Global Typefilter Ptr. + * + * Without the atomic load, it isn't guaranteed that the loads of + * Global MemoryEntry Ptr aren't speculated. + * + * The global pointers transition from NULL -> valid once and only once, + * and never change after becoming valid. This means that having passed + * the first atomic load test of Global Typefilter Ptr, this function + * can then safely use the remaining global state without atomic checks. + */ + if (!os_atomic_load(&kdbg_typefilter, acquire)) { + return EINVAL; + } + + assert(kdbg_typefilter_memory_entry); + + mach_vm_offset_t user_addr = 0; + vm_map_t user_map = current_map(); + + ret = mach_to_bsd_errno( + mach_vm_map_kernel(user_map, // target map + &user_addr, // [in, out] target address + TYPEFILTER_ALLOC_SIZE, // initial size + 0, // mask (alignment?) + VM_FLAGS_ANYWHERE, // flags + VM_MAP_KERNEL_FLAGS_NONE, + VM_KERN_MEMORY_NONE, + kdbg_typefilter_memory_entry, // port (memory entry!) + 0, // offset (in memory entry) + false, // should copy + VM_PROT_READ, // cur_prot + VM_PROT_READ, // max_prot + VM_INHERIT_SHARE)); // inherit behavior on fork + + if (ret == KERN_SUCCESS) { + vm_size_t user_ptr_size = vm_map_is_64bit(user_map) ? 8 : 4; + ret = copyout(CAST_DOWN(void *, &user_addr), uap->addr, user_ptr_size ); + + if (ret != KERN_SUCCESS) { + mach_vm_deallocate(user_map, user_addr, TYPEFILTER_ALLOC_SIZE); + } + } + + return ret; +} + +/* + * Support syscall SYS_kdebug_trace. U64->K32 args may get truncated in kdebug_trace64 + */ +int +kdebug_trace(struct proc *p, struct kdebug_trace_args *uap, int32_t *retval) +{ + struct kdebug_trace64_args uap64; + + uap64.code = uap->code; + uap64.arg1 = uap->arg1; + uap64.arg2 = uap->arg2; + uap64.arg3 = uap->arg3; + uap64.arg4 = uap->arg4; + + return kdebug_trace64(p, &uap64, retval); +} + +/* + * Support syscall SYS_kdebug_trace64. 64-bit args on K32 will get truncated + * to fit in 32-bit record format. + * + * It is intentional that error conditions are not checked until kdebug is + * enabled. This is to match the userspace wrapper behavior, which is optimizing + * for non-error case performance. + */ +int +kdebug_trace64(__unused struct proc *p, struct kdebug_trace64_args *uap, __unused int32_t *retval) +{ + int err; + + if (__probable(kdebug_enable == 0)) { + return 0; + } + + if ((err = kdebug_validate_debugid(uap->code)) != 0) { + return err; + } + + kernel_debug_internal(uap->code, (uintptr_t)uap->arg1, + (uintptr_t)uap->arg2, (uintptr_t)uap->arg3, (uintptr_t)uap->arg4, + (uintptr_t)thread_tid(current_thread()), 0); + + return 0; +} + +/* + * Adding enough padding to contain a full tracepoint for the last + * portion of the string greatly simplifies the logic of splitting the + * string between tracepoints. Full tracepoints can be generated using + * the buffer itself, without having to manually add zeros to pad the + * arguments. + */ + +/* 2 string args in first tracepoint and 9 string data tracepoints */ +#define STR_BUF_ARGS (2 + (9 * 4)) +/* times the size of each arg on K64 */ +#define MAX_STR_LEN (STR_BUF_ARGS * sizeof(uint64_t)) +/* on K32, ending straddles a tracepoint, so reserve blanks */ +#define STR_BUF_SIZE (MAX_STR_LEN + (2 * sizeof(uint32_t))) + +/* + * This function does no error checking and assumes that it is called with + * the correct arguments, including that the buffer pointed to by str is at + * least STR_BUF_SIZE bytes. However, str must be aligned to word-size and + * be NUL-terminated. In cases where a string can fit evenly into a final + * tracepoint without its NUL-terminator, this function will not end those + * strings with a NUL in trace. It's up to clients to look at the function + * qualifier for DBG_FUNC_END in this case, to end the string. + */ +static uint64_t +kernel_debug_string_internal(uint32_t debugid, uint64_t str_id, void *vstr, + size_t str_len) +{ + /* str must be word-aligned */ + uintptr_t *str = vstr; + size_t written = 0; + uintptr_t thread_id; + int i; + uint32_t trace_debugid = TRACEDBG_CODE(DBG_TRACE_STRING, + TRACE_STRING_GLOBAL); + + thread_id = (uintptr_t)thread_tid(current_thread()); + + /* if the ID is being invalidated, just emit that */ + if (str_id != 0 && str_len == 0) { + kernel_debug_internal(trace_debugid | DBG_FUNC_START | DBG_FUNC_END, + (uintptr_t)debugid, (uintptr_t)str_id, 0, 0, thread_id, 0); + return str_id; + } + + /* generate an ID, if necessary */ + if (str_id == 0) { + str_id = OSIncrementAtomic64((SInt64 *)&g_curr_str_id); + str_id = (str_id & STR_ID_MASK) | g_str_id_signature; + } + + trace_debugid |= DBG_FUNC_START; + /* string can fit in a single tracepoint */ + if (str_len <= (2 * sizeof(uintptr_t))) { + trace_debugid |= DBG_FUNC_END; + } + + kernel_debug_internal(trace_debugid, (uintptr_t)debugid, (uintptr_t)str_id, + str[0], str[1], thread_id, 0); + + trace_debugid &= KDBG_EVENTID_MASK; + i = 2; + written += 2 * sizeof(uintptr_t); + + for (; written < str_len; i += 4, written += 4 * sizeof(uintptr_t)) { + if ((written + (4 * sizeof(uintptr_t))) >= str_len) { + trace_debugid |= DBG_FUNC_END; + } + kernel_debug_internal(trace_debugid, str[i], + str[i + 1], + str[i + 2], + str[i + 3], thread_id, 0); + } + + return str_id; +} + +/* + * Returns true if the current process can emit events, and false otherwise. + * Trace system and scheduling events circumvent this check, as do events + * emitted in interrupt context. + */ +static bool +kdebug_current_proc_enabled(uint32_t debugid) +{ + /* can't determine current process in interrupt context */ + if (ml_at_interrupt_context()) { + return true; + } + + /* always emit trace system and scheduling events */ + if ((KDBG_EXTRACT_CLASS(debugid) == DBG_TRACE || + (debugid & KDBG_CSC_MASK) == MACHDBG_CODE(DBG_MACH_SCHED, 0))) { + return true; + } + + if (kd_ctrl_page.kdebug_flags & KDBG_PIDCHECK) { + proc_t cur_proc = current_proc(); + + /* only the process with the kdebug bit set is allowed */ + if (cur_proc && !(cur_proc->p_kdebug)) { + return false; + } + } else if (kd_ctrl_page.kdebug_flags & KDBG_PIDEXCLUDE) { + proc_t cur_proc = current_proc(); + + /* every process except the one with the kdebug bit set is allowed */ + if (cur_proc && cur_proc->p_kdebug) { + return false; + } + } + + return true; +} + +bool +kdebug_debugid_enabled(uint32_t debugid) +{ + /* if no filtering is enabled */ + if (!kd_ctrl_page.kdebug_slowcheck) { + return true; + } + + return kdebug_debugid_explicitly_enabled(debugid); +} + +bool +kdebug_debugid_explicitly_enabled(uint32_t debugid) +{ + if (kd_ctrl_page.kdebug_flags & KDBG_TYPEFILTER_CHECK) { + return typefilter_is_debugid_allowed(kdbg_typefilter, debugid); + } else if (KDBG_EXTRACT_CLASS(debugid) == DBG_TRACE) { + return true; + } else if (kd_ctrl_page.kdebug_flags & KDBG_RANGECHECK) { + if (debugid < kdlog_beg || debugid > kdlog_end) { + return false; + } + } else if (kd_ctrl_page.kdebug_flags & KDBG_VALCHECK) { + if ((debugid & KDBG_EVENTID_MASK) != kdlog_value1 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value2 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value3 && + (debugid & KDBG_EVENTID_MASK) != kdlog_value4) { + return false; + } + } + + return true; +} + +bool +kdebug_using_continuous_time(void) +{ + return kdebug_enable & KDEBUG_ENABLE_CONT_TIME; +} + +/* + * Returns 0 if a string can be traced with these arguments. Returns errno + * value if error occurred. + */ +static errno_t +kdebug_check_trace_string(uint32_t debugid, uint64_t str_id) +{ + /* if there are function qualifiers on the debugid */ + if (debugid & ~KDBG_EVENTID_MASK) { + return EINVAL; + } + + if (kdebug_validate_debugid(debugid)) { + return EPERM; + } + + if (str_id != 0 && (str_id & STR_ID_SIG_MASK) != g_str_id_signature) { + return EINVAL; + } + + return 0; +} + +/* + * Implementation of KPI kernel_debug_string. + */ +int +kernel_debug_string(uint32_t debugid, uint64_t *str_id, const char *str) +{ + /* arguments to tracepoints must be word-aligned */ + __attribute__((aligned(sizeof(uintptr_t)))) char str_buf[STR_BUF_SIZE]; + static_assert(sizeof(str_buf) > MAX_STR_LEN); + vm_size_t len_copied; + int err; + + assert(str_id); + + if (__probable(kdebug_enable == 0)) { + return 0; + } + + if (!kdebug_current_proc_enabled(debugid)) { + return 0; + } + + if (!kdebug_debugid_enabled(debugid)) { + return 0; + } + + if ((err = kdebug_check_trace_string(debugid, *str_id)) != 0) { + return err; + } + + if (str == NULL) { + if (str_id == 0) { + return EINVAL; + } + + *str_id = kernel_debug_string_internal(debugid, *str_id, NULL, 0); + return 0; + } + + memset(str_buf, 0, sizeof(str_buf)); + len_copied = strlcpy(str_buf, str, MAX_STR_LEN + 1); + *str_id = kernel_debug_string_internal(debugid, *str_id, str_buf, + len_copied); + return 0; +} + +/* + * Support syscall kdebug_trace_string. + */ +int +kdebug_trace_string(__unused struct proc *p, + struct kdebug_trace_string_args *uap, + uint64_t *retval) +{ + __attribute__((aligned(sizeof(uintptr_t)))) char str_buf[STR_BUF_SIZE]; + static_assert(sizeof(str_buf) > MAX_STR_LEN); + size_t len_copied; + int err; + + if (__probable(kdebug_enable == 0)) { + return 0; + } + + if (!kdebug_current_proc_enabled(uap->debugid)) { + return 0; + } + + if (!kdebug_debugid_enabled(uap->debugid)) { + return 0; + } + + if ((err = kdebug_check_trace_string(uap->debugid, uap->str_id)) != 0) { + return err; + } + + if (uap->str == USER_ADDR_NULL) { + if (uap->str_id == 0) { + return EINVAL; + } + + *retval = kernel_debug_string_internal(uap->debugid, uap->str_id, + NULL, 0); + return 0; + } + + memset(str_buf, 0, sizeof(str_buf)); + err = copyinstr(uap->str, str_buf, MAX_STR_LEN + 1, &len_copied); + + /* it's alright to truncate the string, so allow ENAMETOOLONG */ + if (err == ENAMETOOLONG) { + str_buf[MAX_STR_LEN] = '\0'; + } else if (err) { + return err; + } + + if (len_copied <= 1) { + return EINVAL; + } + + /* convert back to a length */ + len_copied--; + + *retval = kernel_debug_string_internal(uap->debugid, uap->str_id, str_buf, + len_copied); + return 0; +} + +static void +kdbg_lock_init(void) +{ + static lck_grp_attr_t *kdebug_lck_grp_attr = NULL; + static lck_attr_t *kdebug_lck_attr = NULL; + + if (kd_ctrl_page.kdebug_flags & KDBG_LOCKINIT) { + return; + } + + assert(kdebug_lck_grp_attr == NULL); + kdebug_lck_grp_attr = lck_grp_attr_alloc_init(); + kdebug_lck_grp = lck_grp_alloc_init("kdebug", kdebug_lck_grp_attr); + kdebug_lck_attr = lck_attr_alloc_init(); + + kds_spin_lock = lck_spin_alloc_init(kdebug_lck_grp, kdebug_lck_attr); + kdw_spin_lock = lck_spin_alloc_init(kdebug_lck_grp, kdebug_lck_attr); + + kd_ctrl_page.kdebug_flags |= KDBG_LOCKINIT; +} + +int +kdbg_bootstrap(bool early_trace) +{ + kd_ctrl_page.kdebug_flags &= ~KDBG_WRAPPED; + + return create_buffers(early_trace); +} + +int +kdbg_reinit(bool early_trace) +{ + int ret = 0; + + /* + * Disable trace collecting + * First make sure we're not in + * the middle of cutting a trace + */ + kernel_debug_disable(); + + /* + * make sure the SLOW_NOLOG is seen + * by everyone that might be trying + * to cut a trace.. + */ + IOSleep(100); + + delete_buffers(); + + kdbg_clear_thread_map(); + ret = kdbg_bootstrap(early_trace); + + RAW_file_offset = 0; + RAW_file_written = 0; + + return ret; +} + +void +kdbg_trace_data(struct proc *proc, long *arg_pid, long *arg_uniqueid) +{ + if (!proc) { + *arg_pid = 0; + *arg_uniqueid = 0; + } else { + *arg_pid = proc->p_pid; + *arg_uniqueid = proc->p_uniqueid; + if ((uint64_t) *arg_uniqueid != proc->p_uniqueid) { + *arg_uniqueid = 0; + } + } +} + + +void +kdbg_trace_string(struct proc *proc, long *arg1, long *arg2, long *arg3, + long *arg4) +{ + if (!proc) { + *arg1 = 0; + *arg2 = 0; + *arg3 = 0; + *arg4 = 0; + return; + } + + const char *procname = proc_best_name(proc); + size_t namelen = strlen(procname); + + long args[4] = { 0 }; + + if (namelen > sizeof(args)) { + namelen = sizeof(args); + } + + strncpy((char *)args, procname, namelen); + + *arg1 = args[0]; + *arg2 = args[1]; + *arg3 = args[2]; + *arg4 = args[3]; +} + +static void +kdbg_resolve_map(thread_t th_act, void *opaque) +{ + kd_threadmap *mapptr; + krt_t *t = (krt_t *)opaque; + + if (t->count < t->maxcount) { + mapptr = &t->map[t->count]; + mapptr->thread = (uintptr_t)thread_tid(th_act); + + (void) strlcpy(mapptr->command, t->atts->task_comm, + sizeof(t->atts->task_comm)); + /* + * Some kernel threads have no associated pid. + * We still need to mark the entry as valid. + */ + if (t->atts->pid) { + mapptr->valid = t->atts->pid; + } else { + mapptr->valid = 1; + } + + t->count++; + } +} + +/* + * + * Writes a cpumap for the given iops_list/cpu_count to the provided buffer. + * + * You may provide a buffer and size, or if you set the buffer to NULL, a + * buffer of sufficient size will be allocated. + * + * If you provide a buffer and it is too small, sets cpumap_size to the number + * of bytes required and returns EINVAL. + * + * On success, if you provided a buffer, cpumap_size is set to the number of + * bytes written. If you did not provide a buffer, cpumap is set to the newly + * allocated buffer and cpumap_size is set to the number of bytes allocated. + * + * NOTE: It may seem redundant to pass both iops and a cpu_count. + * + * We may be reporting data from "now", or from the "past". + * + * The "past" data would be for kdbg_readcpumap(). + * + * If we do not pass both iops and cpu_count, and iops is NULL, this function + * will need to read "now" state to get the number of cpus, which would be in + * error if we were reporting "past" state. + */ + +int +kdbg_cpumap_init_internal(kd_iop_t* iops, uint32_t cpu_count, uint8_t** cpumap, uint32_t* cpumap_size) +{ + assert(cpumap); + assert(cpumap_size); + assert(cpu_count); + assert(!iops || iops->cpu_id + 1 == cpu_count); + + uint32_t bytes_needed = sizeof(kd_cpumap_header) + cpu_count * sizeof(kd_cpumap); + uint32_t bytes_available = *cpumap_size; + *cpumap_size = bytes_needed; + + if (*cpumap == NULL) { + if (kmem_alloc(kernel_map, (vm_offset_t*)cpumap, (vm_size_t)*cpumap_size, VM_KERN_MEMORY_DIAG) != KERN_SUCCESS) { + return ENOMEM; + } + bzero(*cpumap, *cpumap_size); + } else if (bytes_available < bytes_needed) { + return EINVAL; + } + + kd_cpumap_header* header = (kd_cpumap_header*)(uintptr_t)*cpumap; + + header->version_no = RAW_VERSION1; + header->cpu_count = cpu_count; + + kd_cpumap* cpus = (kd_cpumap*)&header[1]; + + int32_t index = cpu_count - 1; + while (iops) { + cpus[index].cpu_id = iops->cpu_id; + cpus[index].flags = KDBG_CPUMAP_IS_IOP; + strlcpy(cpus[index].name, iops->callback.iop_name, sizeof(cpus->name)); + + iops = iops->next; + index--; + } + + while (index >= 0) { + cpus[index].cpu_id = index; + cpus[index].flags = 0; + strlcpy(cpus[index].name, "AP", sizeof(cpus->name)); + + index--; + } + + return KERN_SUCCESS; +} + +void +kdbg_thrmap_init(void) +{ + ktrace_assert_lock_held(); + + if (kd_ctrl_page.kdebug_flags & KDBG_MAPINIT) { + return; + } + + kd_mapptr = kdbg_thrmap_init_internal(0, &kd_mapsize, &kd_mapcount); + + if (kd_mapptr) { + kd_ctrl_page.kdebug_flags |= KDBG_MAPINIT; + } +} + +static kd_threadmap * +kdbg_thrmap_init_internal(unsigned int count, unsigned int *mapsize, unsigned int *mapcount) +{ + kd_threadmap *mapptr; + proc_t p; + struct krt akrt; + int tts_count = 0; /* number of task-to-string structures */ + struct tts *tts_mapptr; + unsigned int tts_mapsize = 0; + vm_offset_t kaddr; + + assert(mapsize != NULL); + assert(mapcount != NULL); + + *mapcount = threads_count; + tts_count = tasks_count; + + /* + * The proc count could change during buffer allocation, + * so introduce a small fudge factor to bump up the + * buffer sizes. This gives new tasks some chance of + * making into the tables. Bump up by 25%. + */ + *mapcount += *mapcount / 4; + tts_count += tts_count / 4; + + *mapsize = *mapcount * sizeof(kd_threadmap); + + if (count && count < *mapcount) { + return 0; + } + + if ((kmem_alloc(kernel_map, &kaddr, (vm_size_t)*mapsize, VM_KERN_MEMORY_DIAG) == KERN_SUCCESS)) { + bzero((void *)kaddr, *mapsize); + mapptr = (kd_threadmap *)kaddr; + } else { + return 0; + } + + tts_mapsize = tts_count * sizeof(struct tts); + + if ((kmem_alloc(kernel_map, &kaddr, (vm_size_t)tts_mapsize, VM_KERN_MEMORY_DIAG) == KERN_SUCCESS)) { + bzero((void *)kaddr, tts_mapsize); + tts_mapptr = (struct tts *)kaddr; + } else { + kmem_free(kernel_map, (vm_offset_t)mapptr, *mapsize); + + return 0; + } + + /* + * Save the proc's name and take a reference for each task associated + * with a valid process. + */ + proc_list_lock(); + + int i = 0; + ALLPROC_FOREACH(p) { + if (i >= tts_count) { + break; + } + if (p->p_lflag & P_LEXIT) { + continue; + } + if (p->task) { + task_reference(p->task); + tts_mapptr[i].task = p->task; + tts_mapptr[i].pid = p->p_pid; + (void)strlcpy(tts_mapptr[i].task_comm, proc_best_name(p), sizeof(tts_mapptr[i].task_comm)); + i++; + } + } + tts_count = i; + + proc_list_unlock(); + + /* + * Initialize thread map data + */ + akrt.map = mapptr; + akrt.count = 0; + akrt.maxcount = *mapcount; + + for (i = 0; i < tts_count; i++) { + akrt.atts = &tts_mapptr[i]; + task_act_iterate_wth_args(tts_mapptr[i].task, kdbg_resolve_map, &akrt); + task_deallocate((task_t)tts_mapptr[i].task); + } + kmem_free(kernel_map, (vm_offset_t)tts_mapptr, tts_mapsize); + + *mapcount = akrt.count; + + return mapptr; +} + +static void +kdbg_clear(void) +{ + /* + * Clean up the trace buffer + * First make sure we're not in + * the middle of cutting a trace + */ + kernel_debug_disable(); + kdbg_disable_typefilter(); + + /* + * make sure the SLOW_NOLOG is seen + * by everyone that might be trying + * to cut a trace.. + */ + IOSleep(100); + + /* reset kdebug state for each process */ + if (kd_ctrl_page.kdebug_flags & (KDBG_PIDCHECK | KDBG_PIDEXCLUDE)) { + proc_list_lock(); + proc_t p; + ALLPROC_FOREACH(p) { + p->p_kdebug = 0; + } + proc_list_unlock(); + } + + kd_ctrl_page.kdebug_flags &= (unsigned int)~KDBG_CKTYPES; + kd_ctrl_page.kdebug_flags &= ~(KDBG_NOWRAP | KDBG_RANGECHECK | KDBG_VALCHECK); + kd_ctrl_page.kdebug_flags &= ~(KDBG_PIDCHECK | KDBG_PIDEXCLUDE); + + kd_ctrl_page.oldest_time = 0; + + delete_buffers(); + nkdbufs = 0; + + /* Clean up the thread map buffer */ + kdbg_clear_thread_map(); + + RAW_file_offset = 0; + RAW_file_written = 0; +} + +void +kdebug_reset(void) +{ + ktrace_assert_lock_held(); + + kdbg_lock_init(); + + kdbg_clear(); + if (kdbg_typefilter) { + typefilter_reject_all(kdbg_typefilter); + typefilter_allow_class(kdbg_typefilter, DBG_TRACE); + } +} + +void +kdebug_free_early_buf(void) +{ +#if !CONFIG_EMBEDDED + /* Must be done with the buffer, so release it back to the VM. + * On embedded targets this buffer is freed when the BOOTDATA segment is freed. */ + ml_static_mfree((vm_offset_t)&kd_early_buffer, sizeof(kd_early_buffer)); +#endif +} + +int +kdbg_setpid(kd_regtype *kdr) +{ + pid_t pid; + int flag, ret = 0; + struct proc *p; + + pid = (pid_t)kdr->value1; + flag = (int)kdr->value2; + + if (pid >= 0) { + if ((p = proc_find(pid)) == NULL) { + ret = ESRCH; + } else { + if (flag == 1) { + /* + * turn on pid check for this and all pids + */ + kd_ctrl_page.kdebug_flags |= KDBG_PIDCHECK; + kd_ctrl_page.kdebug_flags &= ~KDBG_PIDEXCLUDE; + kdbg_set_flags(SLOW_CHECKS, 0, true); + + p->p_kdebug = 1; + } else { + /* + * turn off pid check for this pid value + * Don't turn off all pid checking though + * + * kd_ctrl_page.kdebug_flags &= ~KDBG_PIDCHECK; + */ + p->p_kdebug = 0; + } + proc_rele(p); + } + } else { + ret = EINVAL; + } + + return ret; +} + +/* This is for pid exclusion in the trace buffer */ +int +kdbg_setpidex(kd_regtype *kdr) +{ + pid_t pid; + int flag, ret = 0; + struct proc *p; + + pid = (pid_t)kdr->value1; + flag = (int)kdr->value2; + + if (pid >= 0) { + if ((p = proc_find(pid)) == NULL) { + ret = ESRCH; + } else { + if (flag == 1) { + /* + * turn on pid exclusion + */ + kd_ctrl_page.kdebug_flags |= KDBG_PIDEXCLUDE; + kd_ctrl_page.kdebug_flags &= ~KDBG_PIDCHECK; + kdbg_set_flags(SLOW_CHECKS, 0, true); + + p->p_kdebug = 1; + } else { + /* + * turn off pid exclusion for this pid value + * Don't turn off all pid exclusion though + * + * kd_ctrl_page.kdebug_flags &= ~KDBG_PIDEXCLUDE; + */ + p->p_kdebug = 0; + } + proc_rele(p); + } + } else { + ret = EINVAL; + } + + return ret; +} + +/* + * The following functions all operate on the "global" typefilter singleton. + */ + +/* + * The tf param is optional, you may pass either a valid typefilter or NULL. + * If you pass a valid typefilter, you release ownership of that typefilter. + */ +static int +kdbg_initialize_typefilter(typefilter_t tf) +{ + ktrace_assert_lock_held(); + assert(!kdbg_typefilter); + assert(!kdbg_typefilter_memory_entry); + typefilter_t deallocate_tf = NULL; + + if (!tf && ((tf = deallocate_tf = typefilter_create()) == NULL)) { + return ENOMEM; + } + + if ((kdbg_typefilter_memory_entry = typefilter_create_memory_entry(tf)) == MACH_PORT_NULL) { + if (deallocate_tf) { + typefilter_deallocate(deallocate_tf); + } + return ENOMEM; + } + + /* + * The atomic store closes a race window with + * the kdebug_typefilter syscall, which assumes + * that any non-null kdbg_typefilter means a + * valid memory_entry is available. + */ + os_atomic_store(&kdbg_typefilter, tf, release); + + return KERN_SUCCESS; +} + +static int +kdbg_copyin_typefilter(user_addr_t addr, size_t size) +{ + int ret = ENOMEM; + typefilter_t tf; + + ktrace_assert_lock_held(); + + if (size != KDBG_TYPEFILTER_BITMAP_SIZE) { + return EINVAL; + } + + if ((tf = typefilter_create())) { + if ((ret = copyin(addr, tf, KDBG_TYPEFILTER_BITMAP_SIZE)) == 0) { + /* The kernel typefilter must always allow DBG_TRACE */ + typefilter_allow_class(tf, DBG_TRACE); + + /* + * If this is the first typefilter; claim it. + * Otherwise copy and deallocate. + * + * Allocating a typefilter for the copyin allows + * the kernel to hold the invariant that DBG_TRACE + * must always be allowed. + */ + if (!kdbg_typefilter) { + if ((ret = kdbg_initialize_typefilter(tf))) { + return ret; + } + tf = NULL; + } else { + typefilter_copy(kdbg_typefilter, tf); + } + + kdbg_enable_typefilter(); + kdbg_iop_list_callback(kd_ctrl_page.kdebug_iops, KD_CALLBACK_TYPEFILTER_CHANGED, kdbg_typefilter); + } + + if (tf) { + typefilter_deallocate(tf); + } + } + + return ret; +} + +/* + * Enable the flags in the control page for the typefilter. Assumes that + * kdbg_typefilter has already been allocated, so events being written + * don't see a bad typefilter. + */ +static void +kdbg_enable_typefilter(void) +{ + assert(kdbg_typefilter); + kd_ctrl_page.kdebug_flags &= ~(KDBG_RANGECHECK | KDBG_VALCHECK); + kd_ctrl_page.kdebug_flags |= KDBG_TYPEFILTER_CHECK; + kdbg_set_flags(SLOW_CHECKS, 0, true); + commpage_update_kdebug_state(); +} + +/* + * Disable the flags in the control page for the typefilter. The typefilter + * may be safely deallocated shortly after this function returns. + */ +static void +kdbg_disable_typefilter(void) +{ + bool notify_iops = kd_ctrl_page.kdebug_flags & KDBG_TYPEFILTER_CHECK; + kd_ctrl_page.kdebug_flags &= ~KDBG_TYPEFILTER_CHECK; + + if ((kd_ctrl_page.kdebug_flags & (KDBG_PIDCHECK | KDBG_PIDEXCLUDE))) { + kdbg_set_flags(SLOW_CHECKS, 0, true); + } else { + kdbg_set_flags(SLOW_CHECKS, 0, false); + } + commpage_update_kdebug_state(); + + if (notify_iops) { + /* + * Notify IOPs that the typefilter will now allow everything. + * Otherwise, they won't know a typefilter is no longer in + * effect. + */ + typefilter_allow_all(kdbg_typefilter); + kdbg_iop_list_callback(kd_ctrl_page.kdebug_iops, + KD_CALLBACK_TYPEFILTER_CHANGED, kdbg_typefilter); + } +} + +uint32_t +kdebug_commpage_state(void) +{ + if (kdebug_enable) { + if (kd_ctrl_page.kdebug_flags & KDBG_TYPEFILTER_CHECK) { + return KDEBUG_COMMPAGE_ENABLE_TYPEFILTER | KDEBUG_COMMPAGE_ENABLE_TRACE; + } + + return KDEBUG_COMMPAGE_ENABLE_TRACE; + } + + return 0; +} + +int +kdbg_setreg(kd_regtype * kdr) +{ + int ret = 0; + unsigned int val_1, val_2, val; + switch (kdr->type) { + case KDBG_CLASSTYPE: + val_1 = (kdr->value1 & 0xff); + val_2 = (kdr->value2 & 0xff); + kdlog_beg = (val_1 << 24); + kdlog_end = (val_2 << 24); + kd_ctrl_page.kdebug_flags &= (unsigned int)~KDBG_CKTYPES; + kd_ctrl_page.kdebug_flags &= ~KDBG_VALCHECK; /* Turn off specific value check */ + kd_ctrl_page.kdebug_flags |= (KDBG_RANGECHECK | KDBG_CLASSTYPE); + kdbg_set_flags(SLOW_CHECKS, 0, true); + break; + case KDBG_SUBCLSTYPE: + val_1 = (kdr->value1 & 0xff); + val_2 = (kdr->value2 & 0xff); + val = val_2 + 1; + kdlog_beg = ((val_1 << 24) | (val_2 << 16)); + kdlog_end = ((val_1 << 24) | (val << 16)); + kd_ctrl_page.kdebug_flags &= (unsigned int)~KDBG_CKTYPES; + kd_ctrl_page.kdebug_flags &= ~KDBG_VALCHECK; /* Turn off specific value check */ + kd_ctrl_page.kdebug_flags |= (KDBG_RANGECHECK | KDBG_SUBCLSTYPE); + kdbg_set_flags(SLOW_CHECKS, 0, true); + break; + case KDBG_RANGETYPE: + kdlog_beg = (kdr->value1); + kdlog_end = (kdr->value2); + kd_ctrl_page.kdebug_flags &= (unsigned int)~KDBG_CKTYPES; + kd_ctrl_page.kdebug_flags &= ~KDBG_VALCHECK; /* Turn off specific value check */ + kd_ctrl_page.kdebug_flags |= (KDBG_RANGECHECK | KDBG_RANGETYPE); + kdbg_set_flags(SLOW_CHECKS, 0, true); + break; + case KDBG_VALCHECK: + kdlog_value1 = (kdr->value1); + kdlog_value2 = (kdr->value2); + kdlog_value3 = (kdr->value3); + kdlog_value4 = (kdr->value4); + kd_ctrl_page.kdebug_flags &= (unsigned int)~KDBG_CKTYPES; + kd_ctrl_page.kdebug_flags &= ~KDBG_RANGECHECK; /* Turn off range check */ + kd_ctrl_page.kdebug_flags |= KDBG_VALCHECK; /* Turn on specific value check */ + kdbg_set_flags(SLOW_CHECKS, 0, true); + break; + case KDBG_TYPENONE: + kd_ctrl_page.kdebug_flags &= (unsigned int)~KDBG_CKTYPES; + + if ((kd_ctrl_page.kdebug_flags & (KDBG_RANGECHECK | KDBG_VALCHECK | + KDBG_PIDCHECK | KDBG_PIDEXCLUDE | + KDBG_TYPEFILTER_CHECK))) { + kdbg_set_flags(SLOW_CHECKS, 0, true); + } else { + kdbg_set_flags(SLOW_CHECKS, 0, false); + } + + kdlog_beg = 0; + kdlog_end = 0; + break; + default: + ret = EINVAL; + break; + } + return ret; +} + +static int +kdbg_write_to_vnode(caddr_t buffer, size_t size, vnode_t vp, vfs_context_t ctx, off_t file_offset) +{ + return vn_rdwr(UIO_WRITE, vp, buffer, size, file_offset, UIO_SYSSPACE, IO_NODELOCKED | IO_UNIT, + vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx)); +} + +int +kdbg_write_v3_chunk_header(user_addr_t buffer, uint32_t tag, uint32_t sub_tag, uint64_t length, vnode_t vp, vfs_context_t ctx) +{ + int ret = KERN_SUCCESS; + kd_chunk_header_v3 header = { + .tag = tag, + .sub_tag = sub_tag, + .length = length, + }; + + // Check that only one of them is valid + assert(!buffer ^ !vp); + assert((vp == NULL) || (ctx != NULL)); + + // Write the 8-byte future_chunk_timestamp field in the payload + if (buffer || vp) { + if (vp) { + ret = kdbg_write_to_vnode((caddr_t)&header, sizeof(kd_chunk_header_v3), vp, ctx, RAW_file_offset); + if (ret) { + goto write_error; + } + RAW_file_offset += (sizeof(kd_chunk_header_v3)); + } else { + ret = copyout(&header, buffer, sizeof(kd_chunk_header_v3)); + if (ret) { + goto write_error; + } + } + } +write_error: + return ret; +} + +static int +kdbg_write_v3_chunk_to_fd(uint32_t tag, uint32_t sub_tag, uint64_t length, void *payload, uint64_t payload_size, int fd) +{ + proc_t p; + struct vfs_context context; + struct fileproc *fp; + vnode_t vp; + p = current_proc(); + + proc_fdlock(p); + if ((fp_lookup(p, fd, &fp, 1))) { + proc_fdunlock(p); + return EFAULT; + } + + context.vc_thread = current_thread(); + context.vc_ucred = fp->f_fglob->fg_cred; + + if (FILEGLOB_DTYPE(fp->f_fglob) != DTYPE_VNODE) { + fp_drop(p, fd, fp, 1); + proc_fdunlock(p); + return EBADF; + } + vp = (struct vnode *) fp->f_fglob->fg_data; + proc_fdunlock(p); + + if ((vnode_getwithref(vp)) == 0) { + RAW_file_offset = fp->f_fglob->fg_offset; + + kd_chunk_header_v3 chunk_header = { + .tag = tag, + .sub_tag = sub_tag, + .length = length, + }; + + int ret = kdbg_write_to_vnode((caddr_t) &chunk_header, sizeof(kd_chunk_header_v3), vp, &context, RAW_file_offset); + if (!ret) { + RAW_file_offset += sizeof(kd_chunk_header_v3); + } + + ret = kdbg_write_to_vnode((caddr_t) payload, (size_t) payload_size, vp, &context, RAW_file_offset); + if (!ret) { + RAW_file_offset += payload_size; + } + + fp->f_fglob->fg_offset = RAW_file_offset; + vnode_put(vp); + } + + fp_drop(p, fd, fp, 0); + return KERN_SUCCESS; +} + +user_addr_t +kdbg_write_v3_event_chunk_header(user_addr_t buffer, uint32_t tag, uint64_t length, vnode_t vp, vfs_context_t ctx) +{ + uint64_t future_chunk_timestamp = 0; + length += sizeof(uint64_t); + + if (kdbg_write_v3_chunk_header(buffer, tag, V3_EVENT_DATA_VERSION, length, vp, ctx)) { + return 0; + } + if (buffer) { + buffer += sizeof(kd_chunk_header_v3); + } + + // Check that only one of them is valid + assert(!buffer ^ !vp); + assert((vp == NULL) || (ctx != NULL)); + + // Write the 8-byte future_chunk_timestamp field in the payload + if (buffer || vp) { + if (vp) { + int ret = kdbg_write_to_vnode((caddr_t)&future_chunk_timestamp, sizeof(uint64_t), vp, ctx, RAW_file_offset); + if (!ret) { + RAW_file_offset += (sizeof(uint64_t)); + } + } else { + if (copyout(&future_chunk_timestamp, buffer, sizeof(uint64_t))) { + return 0; + } + } + } + + return buffer + sizeof(uint64_t); +} + +int +kdbg_write_v3_header(user_addr_t user_header, size_t *user_header_size, int fd) +{ + int ret = KERN_SUCCESS; + + uint8_t* cpumap = 0; + uint32_t cpumap_size = 0; + uint32_t thrmap_size = 0; + + size_t bytes_needed = 0; + + // Check that only one of them is valid + assert(!user_header ^ !fd); + assert(user_header_size); + + if (!(kd_ctrl_page.kdebug_flags & KDBG_BUFINIT)) { + ret = EINVAL; + goto bail; + } + + if (!(user_header || fd)) { + ret = EINVAL; + goto bail; + } + + // Initialize the cpu map + ret = kdbg_cpumap_init_internal(kd_ctrl_page.kdebug_iops, kd_ctrl_page.kdebug_cpus, &cpumap, &cpumap_size); + if (ret != KERN_SUCCESS) { + goto bail; + } + + // Check if a thread map is initialized + if (!kd_mapptr) { + ret = EINVAL; + goto bail; + } + thrmap_size = kd_mapcount * sizeof(kd_threadmap); + + mach_timebase_info_data_t timebase = {0, 0}; + clock_timebase_info(&timebase); + + // Setup the header. + // See v3 header description in sys/kdebug.h for more inforamtion. + kd_header_v3 header = { + .tag = RAW_VERSION3, + .sub_tag = V3_HEADER_VERSION, + .length = (sizeof(kd_header_v3) + cpumap_size - sizeof(kd_cpumap_header)), + .timebase_numer = timebase.numer, + .timebase_denom = timebase.denom, + .timestamp = 0, /* FIXME rdar://problem/22053009 */ + .walltime_secs = 0, + .walltime_usecs = 0, + .timezone_minuteswest = 0, + .timezone_dst = 0, +#if defined(__LP64__) + .flags = 1, +#else + .flags = 0, +#endif + }; + + // If its a buffer, check if we have enough space to copy the header and the maps. + if (user_header) { + bytes_needed = header.length + thrmap_size + (2 * sizeof(kd_chunk_header_v3)); + if (*user_header_size < bytes_needed) { + ret = EINVAL; + goto bail; + } + } + + // Start writing the header + if (fd) { + void *hdr_ptr = (void *)(((uintptr_t) &header) + sizeof(kd_chunk_header_v3)); + size_t payload_size = (sizeof(kd_header_v3) - sizeof(kd_chunk_header_v3)); + + ret = kdbg_write_v3_chunk_to_fd(RAW_VERSION3, V3_HEADER_VERSION, header.length, hdr_ptr, payload_size, fd); + if (ret) { + goto bail; + } + } else { + if (copyout(&header, user_header, sizeof(kd_header_v3))) { + ret = EFAULT; + goto bail; + } + // Update the user pointer + user_header += sizeof(kd_header_v3); + } + + // Write a cpu map. This is a sub chunk of the header + cpumap = (uint8_t*)((uintptr_t) cpumap + sizeof(kd_cpumap_header)); + size_t payload_size = (size_t)(cpumap_size - sizeof(kd_cpumap_header)); + if (fd) { + ret = kdbg_write_v3_chunk_to_fd(V3_CPU_MAP, V3_CPUMAP_VERSION, payload_size, (void *)cpumap, payload_size, fd); + if (ret) { + goto bail; + } + } else { + ret = kdbg_write_v3_chunk_header(user_header, V3_CPU_MAP, V3_CPUMAP_VERSION, payload_size, NULL, NULL); + if (ret) { + goto bail; + } + user_header += sizeof(kd_chunk_header_v3); + if (copyout(cpumap, user_header, payload_size)) { + ret = EFAULT; + goto bail; + } + // Update the user pointer + user_header += payload_size; + } + + // Write a thread map + if (fd) { + ret = kdbg_write_v3_chunk_to_fd(V3_THREAD_MAP, V3_THRMAP_VERSION, thrmap_size, (void *)kd_mapptr, thrmap_size, fd); + if (ret) { + goto bail; + } + } else { + ret = kdbg_write_v3_chunk_header(user_header, V3_THREAD_MAP, V3_THRMAP_VERSION, thrmap_size, NULL, NULL); + if (ret) { + goto bail; + } + user_header += sizeof(kd_chunk_header_v3); + if (copyout(kd_mapptr, user_header, thrmap_size)) { + ret = EFAULT; + goto bail; + } + user_header += thrmap_size; + } + + if (fd) { + RAW_file_written += bytes_needed; + } + + *user_header_size = bytes_needed; +bail: + if (cpumap) { + kmem_free(kernel_map, (vm_offset_t)cpumap, cpumap_size); + } + return ret; +} + +int +kdbg_readcpumap(user_addr_t user_cpumap, size_t *user_cpumap_size) +{ + uint8_t* cpumap = NULL; + uint32_t cpumap_size = 0; + int ret = KERN_SUCCESS; + + if (kd_ctrl_page.kdebug_flags & KDBG_BUFINIT) { + if (kdbg_cpumap_init_internal(kd_ctrl_page.kdebug_iops, kd_ctrl_page.kdebug_cpus, &cpumap, &cpumap_size) == KERN_SUCCESS) { + if (user_cpumap) { + size_t bytes_to_copy = (*user_cpumap_size >= cpumap_size) ? cpumap_size : *user_cpumap_size; + if (copyout(cpumap, user_cpumap, (size_t)bytes_to_copy)) { + ret = EFAULT; + } + } + *user_cpumap_size = cpumap_size; + kmem_free(kernel_map, (vm_offset_t)cpumap, cpumap_size); + } else { + ret = EINVAL; + } + } else { + ret = EINVAL; + } + + return ret; +} + +int +kdbg_readcurthrmap(user_addr_t buffer, size_t *bufsize) +{ + kd_threadmap *mapptr; + unsigned int mapsize; + unsigned int mapcount; + unsigned int count = 0; + int ret = 0; + + count = *bufsize / sizeof(kd_threadmap); + *bufsize = 0; + + if ((mapptr = kdbg_thrmap_init_internal(count, &mapsize, &mapcount))) { + if (copyout(mapptr, buffer, mapcount * sizeof(kd_threadmap))) { + ret = EFAULT; + } else { + *bufsize = (mapcount * sizeof(kd_threadmap)); + } + + kmem_free(kernel_map, (vm_offset_t)mapptr, mapsize); + } else { + ret = EINVAL; + } + + return ret; +} + +static int +kdbg_write_v1_header(bool write_thread_map, vnode_t vp, vfs_context_t ctx) +{ + int ret = 0; + RAW_header header; + clock_sec_t secs; + clock_usec_t usecs; + char *pad_buf; + uint32_t pad_size; + uint32_t extra_thread_count = 0; + uint32_t cpumap_size; + size_t map_size = 0; + size_t map_count = 0; + + if (write_thread_map) { + assert(kd_ctrl_page.kdebug_flags & KDBG_MAPINIT); + map_count = kd_mapcount; + map_size = map_count * sizeof(kd_threadmap); + } + + /* + * Without the buffers initialized, we cannot construct a CPU map or a + * thread map, and cannot write a header. + */ + if (!(kd_ctrl_page.kdebug_flags & KDBG_BUFINIT)) { + return EINVAL; + } + + /* + * To write a RAW_VERSION1+ file, we must embed a cpumap in the + * "padding" used to page align the events following the threadmap. If + * the threadmap happens to not require enough padding, we artificially + * increase its footprint until it needs enough padding. + */ + + assert(vp); + assert(ctx); + + pad_size = PAGE_16KB - ((sizeof(RAW_header) + map_size) & PAGE_MASK_64); + cpumap_size = sizeof(kd_cpumap_header) + kd_ctrl_page.kdebug_cpus * sizeof(kd_cpumap); + + if (cpumap_size > pad_size) { + /* If the cpu map doesn't fit in the current available pad_size, + * we increase the pad_size by 16K. We do this so that the event + * data is always available on a page aligned boundary for both + * 4k and 16k systems. We enforce this alignment for the event + * data so that we can take advantage of optimized file/disk writes. + */ + pad_size += PAGE_16KB; + } + + /* The way we are silently embedding a cpumap in the "padding" is by artificially + * increasing the number of thread entries. However, we'll also need to ensure that + * the cpumap is embedded in the last 4K page before when the event data is expected. + * This way the tools can read the data starting the next page boundary on both + * 4K and 16K systems preserving compatibility with older versions of the tools + */ + if (pad_size > PAGE_4KB) { + pad_size -= PAGE_4KB; + extra_thread_count = (pad_size / sizeof(kd_threadmap)) + 1; + } + + memset(&header, 0, sizeof(header)); + header.version_no = RAW_VERSION1; + header.thread_count = map_count + extra_thread_count; + + clock_get_calendar_microtime(&secs, &usecs); + header.TOD_secs = secs; + header.TOD_usecs = usecs; + + ret = vn_rdwr(UIO_WRITE, vp, (caddr_t)&header, sizeof(RAW_header), RAW_file_offset, + UIO_SYSSPACE, IO_NODELOCKED | IO_UNIT, vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx)); + if (ret) { + goto write_error; + } + RAW_file_offset += sizeof(RAW_header); + RAW_file_written += sizeof(RAW_header); + + if (write_thread_map) { + ret = vn_rdwr(UIO_WRITE, vp, (caddr_t)kd_mapptr, map_size, RAW_file_offset, + UIO_SYSSPACE, IO_NODELOCKED | IO_UNIT, vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx)); + if (ret) { + goto write_error; + } + + RAW_file_offset += map_size; + RAW_file_written += map_size; + } + + if (extra_thread_count) { + pad_size = extra_thread_count * sizeof(kd_threadmap); + pad_buf = kalloc(pad_size); + if (!pad_buf) { + ret = ENOMEM; + goto write_error; + } + memset(pad_buf, 0, pad_size); + + ret = vn_rdwr(UIO_WRITE, vp, (caddr_t)pad_buf, pad_size, RAW_file_offset, + UIO_SYSSPACE, IO_NODELOCKED | IO_UNIT, vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx)); + kfree(pad_buf, pad_size); + if (ret) { + goto write_error; + } + + RAW_file_offset += pad_size; + RAW_file_written += pad_size; + } + + pad_size = PAGE_SIZE - (RAW_file_offset & PAGE_MASK_64); + if (pad_size) { + pad_buf = (char *)kalloc(pad_size); + if (!pad_buf) { + ret = ENOMEM; + goto write_error; + } + memset(pad_buf, 0, pad_size); + + /* + * embed a cpumap in the padding bytes. + * older code will skip this. + * newer code will know how to read it. + */ + uint32_t temp = pad_size; + if (kdbg_cpumap_init_internal(kd_ctrl_page.kdebug_iops, kd_ctrl_page.kdebug_cpus, (uint8_t**)&pad_buf, &temp) != KERN_SUCCESS) { + memset(pad_buf, 0, pad_size); + } + + ret = vn_rdwr(UIO_WRITE, vp, (caddr_t)pad_buf, pad_size, RAW_file_offset, + UIO_SYSSPACE, IO_NODELOCKED | IO_UNIT, vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx)); + kfree(pad_buf, pad_size); + if (ret) { + goto write_error; + } + + RAW_file_offset += pad_size; + RAW_file_written += pad_size; + } + +write_error: + return ret; +} + +static void +kdbg_clear_thread_map(void) +{ + ktrace_assert_lock_held(); + + if (kd_ctrl_page.kdebug_flags & KDBG_MAPINIT) { + assert(kd_mapptr != NULL); + kmem_free(kernel_map, (vm_offset_t)kd_mapptr, kd_mapsize); + kd_mapptr = NULL; + kd_mapsize = 0; + kd_mapcount = 0; + kd_ctrl_page.kdebug_flags &= ~KDBG_MAPINIT; + } +} + +/* + * Write out a version 1 header and the thread map, if it is initialized, to a + * vnode. Used by KDWRITEMAP and kdbg_dump_trace_to_file. + * + * Returns write errors from vn_rdwr if a write fails. Returns ENODATA if the + * thread map has not been initialized, but the header will still be written. + * Returns ENOMEM if padding could not be allocated. Returns 0 otherwise. + */ +static int +kdbg_write_thread_map(vnode_t vp, vfs_context_t ctx) +{ + int ret = 0; + bool map_initialized; + + ktrace_assert_lock_held(); + assert(ctx != NULL); + + map_initialized = (kd_ctrl_page.kdebug_flags & KDBG_MAPINIT); + + ret = kdbg_write_v1_header(map_initialized, vp, ctx); + if (ret == 0) { + if (map_initialized) { + kdbg_clear_thread_map(); + } else { + ret = ENODATA; + } + } + + return ret; +} + +/* + * Copy out the thread map to a user space buffer. Used by KDTHRMAP. + * + * Returns copyout errors if the copyout fails. Returns ENODATA if the thread + * map has not been initialized. Returns EINVAL if the buffer provided is not + * large enough for the entire thread map. Returns 0 otherwise. + */ +static int +kdbg_copyout_thread_map(user_addr_t buffer, size_t *buffer_size) +{ + bool map_initialized; + size_t map_size; + int ret = 0; + + ktrace_assert_lock_held(); + assert(buffer_size != NULL); + + map_initialized = (kd_ctrl_page.kdebug_flags & KDBG_MAPINIT); + if (!map_initialized) { + return ENODATA; + } + + map_size = kd_mapcount * sizeof(kd_threadmap); + if (*buffer_size < map_size) { + return EINVAL; + } + + ret = copyout(kd_mapptr, buffer, map_size); + if (ret == 0) { + kdbg_clear_thread_map(); + } + + return ret; } -void -kdbg_mapinit(void) +int +kdbg_readthrmap_v3(user_addr_t buffer, size_t buffer_size, int fd) { - struct proc *p; - struct krt akrt; - int tts_count; /* number of task-to-string structures */ - struct tts *tts_mapptr; - unsigned int tts_mapsize = 0; - unsigned int tts_maptomem=0; - int i; + int ret = 0; + bool map_initialized; + size_t map_size; + + ktrace_assert_lock_held(); + if ((!fd && !buffer) || (fd && buffer)) { + return EINVAL; + } - if (kdebug_flags & KDBG_MAPINIT) - return; + map_initialized = (kd_ctrl_page.kdebug_flags & KDBG_MAPINIT); + map_size = kd_mapcount * sizeof(kd_threadmap); - /* need to use PROC_SCANPROCLIST with proc_iterate */ - proc_list_lock(); + if (map_initialized && (buffer_size >= map_size)) { + ret = kdbg_write_v3_header(buffer, &buffer_size, fd); - /* Calculate the sizes of map buffers*/ - for (p = allproc.lh_first, kd_mapcount=0, tts_count=0; p; - p = p->p_list.le_next) - { - kd_mapcount += get_task_numacts((task_t)p->task); - tts_count++; - } + if (ret == 0) { + kdbg_clear_thread_map(); + } + } else { + ret = EINVAL; + } - proc_list_unlock(); + return ret; +} +static void +kdbg_set_nkdbufs(unsigned int req_nkdbufs) +{ /* - * The proc count could change during buffer allocation, - * so introduce a small fudge factor to bump up the - * buffer sizes. This gives new tasks some chance of - * making into the tables. Bump up by 10%. + * Only allow allocation up to half the available memory (sane_size). */ - kd_mapcount += kd_mapcount/10; - tts_count += tts_count/10; + uint64_t max_nkdbufs = (sane_size / 2) / sizeof(kd_buf); + nkdbufs = (req_nkdbufs > max_nkdbufs) ? max_nkdbufs : req_nkdbufs; +} - kd_mapsize = kd_mapcount * sizeof(kd_threadmap); - if((kmem_alloc(kernel_map, & kd_maptomem, - (vm_size_t)kd_mapsize) == KERN_SUCCESS)) - { - kd_mapptr = (kd_threadmap *) kd_maptomem; - bzero(kd_mapptr, kd_mapsize); - } - else - kd_mapptr = (kd_threadmap *) 0; +/* + * Block until there are `n_storage_threshold` storage units filled with + * events or `timeout_ms` milliseconds have passed. If `locked_wait` is true, + * `ktrace_lock` is held while waiting. This is necessary while waiting to + * write events out of the buffers. + * + * Returns true if the threshold was reached and false otherwise. + * + * Called with `ktrace_lock` locked and interrupts enabled. + */ +static bool +kdbg_wait(uint64_t timeout_ms, bool locked_wait) +{ + int wait_result = THREAD_AWAKENED; + uint64_t abstime = 0; - tts_mapsize = tts_count * sizeof(struct tts); - if((kmem_alloc(kernel_map, & tts_maptomem, - (vm_size_t)tts_mapsize) == KERN_SUCCESS)) - { - tts_mapptr = (struct tts *) tts_maptomem; - bzero(tts_mapptr, tts_mapsize); + ktrace_assert_lock_held(); + + if (timeout_ms != 0) { + uint64_t ns = timeout_ms * NSEC_PER_MSEC; + nanoseconds_to_absolutetime(ns, &abstime); + clock_absolutetime_interval_to_deadline(abstime, &abstime); } - else - tts_mapptr = (struct tts *) 0; + bool s = ml_set_interrupts_enabled(false); + if (!s) { + panic("kdbg_wait() called with interrupts disabled"); + } + lck_spin_lock_grp(kdw_spin_lock, kdebug_lck_grp); - /* - * We need to save the procs command string - * and take a reference for each task associated - * with a valid process - */ + if (!locked_wait) { + /* drop the mutex to allow others to access trace */ + ktrace_unlock(); + } - if (tts_mapptr) { - /* should use proc_iterate */ - proc_list_lock(); + while (wait_result == THREAD_AWAKENED && + kd_ctrl_page.kds_inuse_count < n_storage_threshold) { + kds_waiter = 1; - for (p = allproc.lh_first, i=0; p && i < tts_count; - p = p->p_list.le_next) { - if (p->p_lflag & P_LEXIT) - continue; - - if (p->task) { - task_reference(p->task); - tts_mapptr[i].task = p->task; - tts_mapptr[i].pid = p->p_pid; - (void)strlcpy(tts_mapptr[i].task_comm, p->p_comm, sizeof(tts_mapptr[i].task_comm)); - i++; - } + if (abstime) { + wait_result = lck_spin_sleep_deadline(kdw_spin_lock, 0, &kds_waiter, THREAD_ABORTSAFE, abstime); + } else { + wait_result = lck_spin_sleep(kdw_spin_lock, 0, &kds_waiter, THREAD_ABORTSAFE); } - tts_count = i; - - proc_list_unlock(); + kds_waiter = 0; } + /* check the count under the spinlock */ + bool threshold_exceeded = (kd_ctrl_page.kds_inuse_count >= n_storage_threshold); - if (kd_mapptr && tts_mapptr) - { - kdebug_flags |= KDBG_MAPINIT; - /* Initialize thread map data */ - akrt.map = kd_mapptr; - akrt.count = 0; - akrt.maxcount = kd_mapcount; - - for (i=0; i < tts_count; i++) - { - akrt.atts = &tts_mapptr[i]; - task_act_iterate_wth_args(tts_mapptr[i].task, kdbg_resolve_map, &akrt); - task_deallocate((task_t) tts_mapptr[i].task); - } - kmem_free(kernel_map, (vm_offset_t)tts_mapptr, tts_mapsize); - } + lck_spin_unlock(kdw_spin_lock); + ml_set_interrupts_enabled(s); + + if (!locked_wait) { + /* pick the mutex back up again */ + ktrace_lock(); + } + + /* write out whether we've exceeded the threshold */ + return threshold_exceeded; } +/* + * Wakeup a thread waiting using `kdbg_wait` if there are at least + * `n_storage_threshold` storage units in use. + */ static void -kdbg_clear(void) +kdbg_wakeup(void) { - /* - * Clean up the trace buffer - * First make sure we're not in - * the middle of cutting a trace - */ - - kdebug_enable &= ~KDEBUG_ENABLE_TRACE; - kdebug_slowcheck = SLOW_NOLOG; + bool need_kds_wakeup = false; /* - * make sure the SLOW_NOLOG is seen - * by everyone that might be trying - * to cut a trace.. + * Try to take the lock here to synchronize with the waiter entering + * the blocked state. Use the try mode to prevent deadlocks caused by + * re-entering this routine due to various trace points triggered in the + * lck_spin_sleep_xxxx routines used to actually enter one of our 2 wait + * conditions. No problem if we fail, there will be lots of additional + * events coming in that will eventually succeed in grabbing this lock. */ - IOSleep(100); - - if (kdebug_enable & KDEBUG_ENABLE_ENTROPY) - kdebug_slowcheck |= SLOW_ENTROPY; + bool s = ml_set_interrupts_enabled(false); - global_state_pid = -1; - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdebug_flags &= ~(KDBG_NOWRAP | KDBG_RANGECHECK | KDBG_VALCHECK); - kdebug_flags &= ~(KDBG_PIDCHECK | KDBG_PIDEXCLUDE); + if (lck_spin_try_lock(kdw_spin_lock)) { + if (kds_waiter && + (kd_ctrl_page.kds_inuse_count >= n_storage_threshold)) { + kds_waiter = 0; + need_kds_wakeup = true; + } + lck_spin_unlock(kdw_spin_lock); + } - delete_buffers(); + ml_set_interrupts_enabled(s); - /* Clean up the thread map buffer */ - kdebug_flags &= ~KDBG_MAPINIT; - kmem_free(kernel_map, (vm_offset_t)kd_mapptr, kd_mapsize); - kd_mapptr = (kd_threadmap *) 0; - kd_mapsize = 0; - kd_mapcount = 0; + if (need_kds_wakeup == true) { + wakeup(&kds_waiter); + } } int -kdbg_setpid(kd_regtype *kdr) +kdbg_control(int *name, u_int namelen, user_addr_t where, size_t *sizep) { - pid_t pid; - int flag, ret=0; - struct proc *p; + int ret = 0; + size_t size = *sizep; + unsigned int value = 0; + kd_regtype kd_Reg; + kbufinfo_t kd_bufinfo; + proc_t p; + + if (name[0] == KERN_KDWRITETR || + name[0] == KERN_KDWRITETR_V3 || + name[0] == KERN_KDWRITEMAP || + name[0] == KERN_KDWRITEMAP_V3 || + name[0] == KERN_KDEFLAGS || + name[0] == KERN_KDDFLAGS || + name[0] == KERN_KDENABLE || + name[0] == KERN_KDSETBUF) { + if (namelen < 2) { + return EINVAL; + } + value = name[1]; + } - pid = (pid_t)kdr->value1; - flag = (int)kdr->value2; + kdbg_lock_init(); + assert(kd_ctrl_page.kdebug_flags & KDBG_LOCKINIT); - if (pid > 0) - { - if ((p = proc_find(pid)) == NULL) - ret = ESRCH; - else - { - if (flag == 1) /* turn on pid check for this and all pids */ - { - kdebug_flags |= KDBG_PIDCHECK; - kdebug_flags &= ~KDBG_PIDEXCLUDE; - kdebug_slowcheck |= SLOW_CHECKS; - - p->p_kdebug = 1; - } - else /* turn off pid check for this pid value */ - { - /* Don't turn off all pid checking though */ - /* kdebug_flags &= ~KDBG_PIDCHECK;*/ - p->p_kdebug = 0; - } - proc_rele(p); - } - } - else - ret = EINVAL; - return(ret); -} + ktrace_lock(); -/* This is for pid exclusion in the trace buffer */ -int -kdbg_setpidex(kd_regtype *kdr) -{ - pid_t pid; - int flag, ret=0; - struct proc *p; + /* + * Some requests only require "read" access to kdebug trace. Regardless, + * tell ktrace that a configuration or read is occurring (and see if it's + * allowed). + */ + if (name[0] != KERN_KDGETBUF && + name[0] != KERN_KDGETREG && + name[0] != KERN_KDREADCURTHRMAP) { + if ((ret = ktrace_configure(KTRACE_KDEBUG))) { + goto out; + } + } else { + if ((ret = ktrace_read_check())) { + goto out; + } + } - pid = (pid_t)kdr->value1; - flag = (int)kdr->value2; + switch (name[0]) { + case KERN_KDGETBUF: + if (size < sizeof(kd_bufinfo.nkdbufs)) { + /* + * There is not enough room to return even + * the first element of the info structure. + */ + ret = EINVAL; + break; + } - if (pid > 0) - { - if ((p = proc_find(pid)) == NULL) - ret = ESRCH; - else - { - if (flag == 1) /* turn on pid exclusion */ - { - kdebug_flags |= KDBG_PIDEXCLUDE; - kdebug_flags &= ~KDBG_PIDCHECK; - kdebug_slowcheck |= SLOW_CHECKS; - - p->p_kdebug = 1; - } - else /* turn off pid exclusion for this pid value */ - { - /* Don't turn off all pid exclusion though */ - /* kdebug_flags &= ~KDBG_PIDEXCLUDE;*/ - p->p_kdebug = 0; - } - proc_rele(p); - } - } - else - ret = EINVAL; - return(ret); -} - -/* This is for setting a maximum decrementer value */ -int -kdbg_setrtcdec(kd_regtype *kdr) -{ - int ret=0; - natural_t decval; + memset(&kd_bufinfo, 0, sizeof(kd_bufinfo)); - decval = (natural_t)kdr->value1; + kd_bufinfo.nkdbufs = nkdbufs; + kd_bufinfo.nkdthreads = kd_mapcount; - if (decval && decval < KDBG_MINRTCDEC) - ret = EINVAL; -#ifdef ppc - else { - maxDec = decval ? decval : 0x7FFFFFFF; /* Set or reset the max decrementer */ - } -#else - else - ret = ENOTSUP; -#endif /* ppc */ + if ((kd_ctrl_page.kdebug_slowcheck & SLOW_NOLOG)) { + kd_bufinfo.nolog = 1; + } else { + kd_bufinfo.nolog = 0; + } - return(ret); -} + kd_bufinfo.flags = kd_ctrl_page.kdebug_flags; +#if defined(__LP64__) + kd_bufinfo.flags |= KDBG_LP64; +#endif + { + int pid = ktrace_get_owning_pid(); + kd_bufinfo.bufid = (pid == 0 ? -1 : pid); + } -int -kdbg_setreg(kd_regtype * kdr) -{ - int ret=0; - unsigned int val_1, val_2, val; - switch (kdr->type) { - - case KDBG_CLASSTYPE : - val_1 = (kdr->value1 & 0xff); - val_2 = (kdr->value2 & 0xff); - kdlog_beg = (val_1<<24); - kdlog_end = (val_2<<24); - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdebug_flags &= ~KDBG_VALCHECK; /* Turn off specific value check */ - kdebug_flags |= (KDBG_RANGECHECK | KDBG_CLASSTYPE); - kdebug_slowcheck |= SLOW_CHECKS; + if (size >= sizeof(kd_bufinfo)) { + /* + * Provide all the info we have + */ + if (copyout(&kd_bufinfo, where, sizeof(kd_bufinfo))) { + ret = EINVAL; + } + } else { + /* + * For backwards compatibility, only provide + * as much info as there is room for. + */ + if (copyout(&kd_bufinfo, where, size)) { + ret = EINVAL; + } + } break; - case KDBG_SUBCLSTYPE : - val_1 = (kdr->value1 & 0xff); - val_2 = (kdr->value2 & 0xff); - val = val_2 + 1; - kdlog_beg = ((val_1<<24) | (val_2 << 16)); - kdlog_end = ((val_1<<24) | (val << 16)); - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdebug_flags &= ~KDBG_VALCHECK; /* Turn off specific value check */ - kdebug_flags |= (KDBG_RANGECHECK | KDBG_SUBCLSTYPE); - kdebug_slowcheck |= SLOW_CHECKS; + + case KERN_KDREADCURTHRMAP: + ret = kdbg_readcurthrmap(where, sizep); break; - case KDBG_RANGETYPE : - kdlog_beg = (kdr->value1); - kdlog_end = (kdr->value2); - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdebug_flags &= ~KDBG_VALCHECK; /* Turn off specific value check */ - kdebug_flags |= (KDBG_RANGECHECK | KDBG_RANGETYPE); - kdebug_slowcheck |= SLOW_CHECKS; + + case KERN_KDEFLAGS: + value &= KDBG_USERFLAGS; + kd_ctrl_page.kdebug_flags |= value; break; - case KDBG_VALCHECK: - kdlog_value1 = (kdr->value1); - kdlog_value2 = (kdr->value2); - kdlog_value3 = (kdr->value3); - kdlog_value4 = (kdr->value4); - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdebug_flags &= ~KDBG_RANGECHECK; /* Turn off range check */ - kdebug_flags |= KDBG_VALCHECK; /* Turn on specific value check */ - kdebug_slowcheck |= SLOW_CHECKS; + + case KERN_KDDFLAGS: + value &= KDBG_USERFLAGS; + kd_ctrl_page.kdebug_flags &= ~value; break; - case KDBG_TYPENONE : - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - if ( (kdebug_flags & (KDBG_RANGECHECK | KDBG_VALCHECK | KDBG_PIDCHECK | KDBG_PIDEXCLUDE)) ) - kdebug_slowcheck |= SLOW_CHECKS; - else - kdebug_slowcheck &= ~SLOW_CHECKS; + case KERN_KDENABLE: + /* + * Enable tracing mechanism. Two types: + * KDEBUG_TRACE is the standard one, + * and KDEBUG_PPT which is a carefully + * chosen subset to avoid performance impact. + */ + if (value) { + /* + * enable only if buffer is initialized + */ + if (!(kd_ctrl_page.kdebug_flags & KDBG_BUFINIT) || + !(value == KDEBUG_ENABLE_TRACE || value == KDEBUG_ENABLE_PPT)) { + ret = EINVAL; + break; + } + kdbg_thrmap_init(); - kdlog_beg = 0; - kdlog_end = 0; + kdbg_set_tracing_enabled(true, value); + } else { + if (!kdebug_enable) { + break; + } + + kernel_debug_disable(); + } + break; + + case KERN_KDSETBUF: + kdbg_set_nkdbufs(value); + break; + + case KERN_KDSETUP: + ret = kdbg_reinit(false); + break; + + case KERN_KDREMOVE: + ktrace_reset(KTRACE_KDEBUG); + break; + + case KERN_KDSETREG: + if (size < sizeof(kd_regtype)) { + ret = EINVAL; + break; + } + if (copyin(where, &kd_Reg, sizeof(kd_regtype))) { + ret = EINVAL; + break; + } + + ret = kdbg_setreg(&kd_Reg); break; - default : + + case KERN_KDGETREG: ret = EINVAL; break; + + case KERN_KDREADTR: + ret = kdbg_read(where, sizep, NULL, NULL, RAW_VERSION1); + break; + + case KERN_KDWRITETR: + case KERN_KDWRITETR_V3: + case KERN_KDWRITEMAP: + case KERN_KDWRITEMAP_V3: + { + struct vfs_context context; + struct fileproc *fp; + size_t number; + vnode_t vp; + int fd; + + if (name[0] == KERN_KDWRITETR || name[0] == KERN_KDWRITETR_V3) { + (void)kdbg_wait(size, true); + } + p = current_proc(); + fd = value; + + proc_fdlock(p); + if ((ret = fp_lookup(p, fd, &fp, 1))) { + proc_fdunlock(p); + break; + } + context.vc_thread = current_thread(); + context.vc_ucred = fp->f_fglob->fg_cred; + + if (FILEGLOB_DTYPE(fp->f_fglob) != DTYPE_VNODE) { + fp_drop(p, fd, fp, 1); + proc_fdunlock(p); + + ret = EBADF; + break; + } + vp = (struct vnode *)fp->f_fglob->fg_data; + proc_fdunlock(p); + + if ((ret = vnode_getwithref(vp)) == 0) { + RAW_file_offset = fp->f_fglob->fg_offset; + if (name[0] == KERN_KDWRITETR || name[0] == KERN_KDWRITETR_V3) { + number = nkdbufs * sizeof(kd_buf); + + KDBG_RELEASE(TRACE_WRITING_EVENTS | DBG_FUNC_START); + if (name[0] == KERN_KDWRITETR_V3) { + ret = kdbg_read(0, &number, vp, &context, RAW_VERSION3); + } else { + ret = kdbg_read(0, &number, vp, &context, RAW_VERSION1); + } + KDBG_RELEASE(TRACE_WRITING_EVENTS | DBG_FUNC_END, number); + + *sizep = number; + } else { + number = kd_mapcount * sizeof(kd_threadmap); + if (name[0] == KERN_KDWRITEMAP_V3) { + ret = kdbg_readthrmap_v3(0, number, fd); + } else { + ret = kdbg_write_thread_map(vp, &context); + } + } + fp->f_fglob->fg_offset = RAW_file_offset; + vnode_put(vp); + } + fp_drop(p, fd, fp, 0); + + break; } - return(ret); -} + case KERN_KDBUFWAIT: + *sizep = kdbg_wait(size, false); + break; -int -kdbg_getreg(__unused kd_regtype * kdr) -{ -#if 0 - int i,j, ret=0; - unsigned int val_1, val_2, val; + case KERN_KDPIDTR: + if (size < sizeof(kd_regtype)) { + ret = EINVAL; + break; + } + if (copyin(where, &kd_Reg, sizeof(kd_regtype))) { + ret = EINVAL; + break; + } - switch (kdr->type) { - case KDBG_CLASSTYPE : - val_1 = (kdr->value1 & 0xff); - val_2 = val_1 + 1; - kdlog_beg = (val_1<<24); - kdlog_end = (val_2<<24); - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdebug_flags |= (KDBG_RANGECHECK | KDBG_CLASSTYPE); + ret = kdbg_setpid(&kd_Reg); break; - case KDBG_SUBCLSTYPE : - val_1 = (kdr->value1 & 0xff); - val_2 = (kdr->value2 & 0xff); - val = val_2 + 1; - kdlog_beg = ((val_1<<24) | (val_2 << 16)); - kdlog_end = ((val_1<<24) | (val << 16)); - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdebug_flags |= (KDBG_RANGECHECK | KDBG_SUBCLSTYPE); + + case KERN_KDPIDEX: + if (size < sizeof(kd_regtype)) { + ret = EINVAL; + break; + } + if (copyin(where, &kd_Reg, sizeof(kd_regtype))) { + ret = EINVAL; + break; + } + + ret = kdbg_setpidex(&kd_Reg); break; - case KDBG_RANGETYPE : - kdlog_beg = (kdr->value1); - kdlog_end = (kdr->value2); - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdebug_flags |= (KDBG_RANGECHECK | KDBG_RANGETYPE); + + case KERN_KDCPUMAP: + ret = kdbg_readcpumap(where, sizep); break; - case KDBG_TYPENONE : - kdebug_flags &= (unsigned int)~KDBG_CKTYPES; - kdlog_beg = 0; - kdlog_end = 0; + + case KERN_KDTHRMAP: + ret = kdbg_copyout_thread_map(where, sizep); + break; + + case KERN_KDSET_TYPEFILTER: { + ret = kdbg_copyin_typefilter(where, size); + break; + } + + case KERN_KDTEST: + ret = kdbg_test(size); break; - default : + + default: ret = EINVAL; break; } -#endif /* 0 */ - return(EINVAL); +out: + ktrace_unlock(); + + return ret; } -int -kdbg_readmap(user_addr_t buffer, size_t *number) -{ - int avail = *number; - int ret = 0; - unsigned int count = 0; +/* + * This code can run for the most part concurrently with kernel_debug_internal()... + * 'release_storage_unit' will take the kds_spin_lock which may cause us to briefly + * synchronize with the recording side of this puzzle... otherwise, we are able to + * move through the lists w/o use of any locks + */ +int +kdbg_read(user_addr_t buffer, size_t *number, vnode_t vp, vfs_context_t ctx, uint32_t file_version) +{ + unsigned int count; + unsigned int cpu, min_cpu; + uint64_t barrier_min = 0, barrier_max = 0, t, earliest_time; + int error = 0; + kd_buf *tempbuf; + uint32_t rcursor; + kd_buf lostevent; + union kds_ptr kdsp; + bool traced_retrograde = false; + struct kd_storage *kdsp_actual; + struct kd_bufinfo *kdbp; + struct kd_bufinfo *min_kdbp; + uint32_t tempbuf_count; + uint32_t tempbuf_number; + uint32_t old_kdebug_flags; + uint32_t old_kdebug_slowcheck; + bool out_of_events = false; + bool wrapped = false; + + assert(number); + count = *number / sizeof(kd_buf); + *number = 0; + + ktrace_assert_lock_held(); + + if (count == 0 || !(kd_ctrl_page.kdebug_flags & KDBG_BUFINIT) || kdcopybuf == 0) { + return EINVAL; + } + + thread_set_eager_preempt(current_thread()); + + memset(&lostevent, 0, sizeof(lostevent)); + lostevent.debugid = TRACE_LOST_EVENTS; + + /* + * Request each IOP to provide us with up to date entries before merging + * buffers together. + */ + kdbg_iop_list_callback(kd_ctrl_page.kdebug_iops, KD_CALLBACK_SYNC_FLUSH, NULL); + + /* + * Capture the current time. Only sort events that have occured + * before now. Since the IOPs are being flushed here, it is possible + * that events occur on the AP while running live tracing. + */ + barrier_max = kdbg_timestamp() & KDBG_TIMESTAMP_MASK; + + /* + * Disable wrap so storage units cannot be stolen out from underneath us + * while merging events. + * + * Because we hold ktrace_lock, no other control threads can be playing + * with kdebug_flags. The code that emits new events could be running, + * but it grabs kds_spin_lock if it needs to acquire a new storage + * chunk, which is where it examines kdebug_flags. If it is adding to + * the same chunk we're reading from, check for that below. + */ + wrapped = disable_wrap(&old_kdebug_slowcheck, &old_kdebug_flags); + + if (count > nkdbufs) { + count = nkdbufs; + } + + if ((tempbuf_count = count) > KDCOPYBUF_COUNT) { + tempbuf_count = KDCOPYBUF_COUNT; + } + + /* + * If the buffers have wrapped, do not emit additional lost events for the + * oldest storage units. + */ + if (wrapped) { + kd_ctrl_page.kdebug_flags &= ~KDBG_WRAPPED; + + for (cpu = 0, kdbp = &kdbip[0]; cpu < kd_ctrl_page.kdebug_cpus; cpu++, kdbp++) { + if ((kdsp = kdbp->kd_list_head).raw == KDS_PTR_NULL) { + continue; + } + kdsp_actual = POINTER_FROM_KDS_PTR(kdsp); + kdsp_actual->kds_lostevents = false; + } + } + /* + * Capture the earliest time where there are events for all CPUs and don't + * emit events with timestamps prior. + */ + barrier_min = kd_ctrl_page.oldest_time; + + while (count) { + tempbuf = kdcopybuf; + tempbuf_number = 0; + + if (wrapped) { + /* + * Emit a lost events tracepoint to indicate that previous events + * were lost -- the thread map cannot be trusted. A new one must + * be taken so tools can analyze the trace in a backwards-facing + * fashion. + */ + kdbg_set_timestamp_and_cpu(&lostevent, barrier_min, 0); + *tempbuf = lostevent; + wrapped = false; + goto nextevent; + } + + /* While space left in merged events scratch buffer. */ + while (tempbuf_count) { + bool lostevents = false; + int lostcpu = 0; + earliest_time = UINT64_MAX; + min_kdbp = NULL; + min_cpu = 0; + + /* Check each CPU's buffers for the earliest event. */ + for (cpu = 0, kdbp = &kdbip[0]; cpu < kd_ctrl_page.kdebug_cpus; cpu++, kdbp++) { + /* Skip CPUs without data in their oldest storage unit. */ + if ((kdsp = kdbp->kd_list_head).raw == KDS_PTR_NULL) { +next_cpu: + continue; + } + /* From CPU data to buffer header to buffer. */ + kdsp_actual = POINTER_FROM_KDS_PTR(kdsp); + +next_event: + /* The next event to be read from this buffer. */ + rcursor = kdsp_actual->kds_readlast; - count = avail/sizeof (kd_threadmap); + /* Skip this buffer if there are no events left. */ + if (rcursor == kdsp_actual->kds_bufindx) { + continue; + } - if (count && (count <= kd_mapcount)) - { - if((kdebug_flags & KDBG_MAPINIT) && kd_mapsize && kd_mapptr) - { - if (*number < kd_mapsize) - ret=EINVAL; - else - { - if (copyout(kd_mapptr, buffer, kd_mapsize)) - ret=EINVAL; - } - } - else - ret=EINVAL; - } - else - ret=EINVAL; - - if ((kdebug_flags & KDBG_MAPINIT) && kd_mapsize && kd_mapptr) - { - kmem_free(kernel_map, (vm_offset_t)kd_mapptr, kd_mapsize); - kdebug_flags &= ~KDBG_MAPINIT; - kd_mapsize = 0; - kd_mapptr = (kd_threadmap *) 0; - kd_mapcount = 0; - } - - return(ret); -} + /* + * Check that this storage unit wasn't stolen and events were + * lost. This must have happened while wrapping was disabled + * in this function. + */ + if (kdsp_actual->kds_lostevents) { + lostevents = true; + kdsp_actual->kds_lostevents = false; + + /* + * The earliest event we can trust is the first one in this + * stolen storage unit. + */ + uint64_t lost_time = + kdbg_get_timestamp(&kdsp_actual->kds_records[0]); + if (kd_ctrl_page.oldest_time < lost_time) { + /* + * If this is the first time we've seen lost events for + * this gap, record its timestamp as the oldest + * timestamp we're willing to merge for the lost events + * tracepoint. + */ + kd_ctrl_page.oldest_time = barrier_min = lost_time; + lostcpu = cpu; + } + } -int -kdbg_getentropy (user_addr_t buffer, size_t *number, int ms_timeout) -{ - int avail = *number; - int ret = 0; + t = kdbg_get_timestamp(&kdsp_actual->kds_records[rcursor]); + + if (t > barrier_max) { + if (kdbg_debug) { + printf("kdebug: FUTURE EVENT: debugid %#8x: " + "time %lld from CPU %u " + "(barrier at time %lld, read %lu events)\n", + kdsp_actual->kds_records[rcursor].debugid, + t, cpu, barrier_max, *number + tempbuf_number); + } + goto next_cpu; + } + if (t < kdsp_actual->kds_timestamp) { + /* + * This indicates the event emitter hasn't completed + * filling in the event (becuase we're looking at the + * buffer that the record head is using). The max barrier + * timestamp should have saved us from seeing these kinds + * of things, but other CPUs might be slow on the up-take. + * + * Bail out so we don't get out-of-order events by + * continuing to read events from other CPUs' events. + */ + out_of_events = true; + break; + } + + /* + * Ignore events that have aged out due to wrapping or storage + * unit exhaustion while merging events. + */ + if (t < barrier_min) { + kdsp_actual->kds_readlast++; + if (kdbg_debug) { + printf("kdebug: PAST EVENT: debugid %#8x: " + "time %lld from CPU %u " + "(barrier at time %lld)\n", + kdsp_actual->kds_records[rcursor].debugid, + t, cpu, barrier_min); + } + + if (kdsp_actual->kds_readlast >= EVENTS_PER_STORAGE_UNIT) { + release_storage_unit(cpu, kdsp.raw); + + if ((kdsp = kdbp->kd_list_head).raw == KDS_PTR_NULL) { + goto next_cpu; + } + kdsp_actual = POINTER_FROM_KDS_PTR(kdsp); + } + + goto next_event; + } - if (kd_entropy_buffer) - return(EBUSY); + /* + * Don't worry about merging any events -- just walk through + * the CPUs and find the latest timestamp of lost events. + */ + if (lostevents) { + continue; + } + + if (t < earliest_time) { + earliest_time = t; + min_kdbp = kdbp; + min_cpu = cpu; + } + } + if (lostevents) { + /* + * If any lost events were hit in the buffers, emit an event + * with the latest timestamp. + */ + kdbg_set_timestamp_and_cpu(&lostevent, barrier_min, lostcpu); + *tempbuf = lostevent; + tempbuf->arg1 = 1; + goto nextevent; + } + if (min_kdbp == NULL) { + /* All buffers ran empty. */ + out_of_events = true; + } + if (out_of_events) { + break; + } - kd_entropy_count = avail/sizeof(mach_timespec_t); - kd_entropy_bufsize = kd_entropy_count * sizeof(mach_timespec_t); - kd_entropy_indx = 0; + kdsp = min_kdbp->kd_list_head; + kdsp_actual = POINTER_FROM_KDS_PTR(kdsp); - /* Enforce maximum entropy entries here if needed */ + /* Copy earliest event into merged events scratch buffer. */ + *tempbuf = kdsp_actual->kds_records[kdsp_actual->kds_readlast++]; - /* allocate entropy buffer */ - if (kmem_alloc(kernel_map, &kd_entropy_buftomem, - (vm_size_t)kd_entropy_bufsize) == KERN_SUCCESS) - { - kd_entropy_buffer = (uint64_t *) kd_entropy_buftomem; - } - else - { - kd_entropy_buffer = (uint64_t *) 0; - kd_entropy_count = 0; - kd_entropy_indx = 0; - return (EINVAL); - } + if (kdsp_actual->kds_readlast == EVENTS_PER_STORAGE_UNIT) { + release_storage_unit(min_cpu, kdsp.raw); + } - if (ms_timeout < 10) - ms_timeout = 10; + /* + * Watch for out of order timestamps (from IOPs). + */ + if (earliest_time < min_kdbp->kd_prev_timebase) { + /* + * If we haven't already, emit a retrograde events event. + * Otherwise, ignore this event. + */ + if (traced_retrograde) { + continue; + } - /* Enable entropy sampling */ - kdebug_enable |= KDEBUG_ENABLE_ENTROPY; - kdebug_slowcheck |= SLOW_ENTROPY; + kdbg_set_timestamp_and_cpu(tempbuf, min_kdbp->kd_prev_timebase, kdbg_get_cpu(tempbuf)); + tempbuf->arg1 = tempbuf->debugid; + tempbuf->arg2 = earliest_time; + tempbuf->arg3 = 0; + tempbuf->arg4 = 0; + tempbuf->debugid = TRACE_RETROGRADE_EVENTS; + traced_retrograde = true; + } else { + min_kdbp->kd_prev_timebase = earliest_time; + } +nextevent: + tempbuf_count--; + tempbuf_number++; + tempbuf++; - ret = tsleep (kdbg_getentropy, PRIBIO | PCATCH, "kd_entropy", (ms_timeout/(1000/HZ))); + if ((RAW_file_written += sizeof(kd_buf)) >= RAW_FLUSH_SIZE) { + break; + } + } + if (tempbuf_number) { + /* + * Remember the latest timestamp of events that we've merged so we + * don't think we've lost events later. + */ + uint64_t latest_time = kdbg_get_timestamp(tempbuf - 1); + if (kd_ctrl_page.oldest_time < latest_time) { + kd_ctrl_page.oldest_time = latest_time; + } + if (file_version == RAW_VERSION3) { + if (!(kdbg_write_v3_event_chunk_header(buffer, V3_RAW_EVENTS, (tempbuf_number * sizeof(kd_buf)), vp, ctx))) { + error = EFAULT; + goto check_error; + } + if (buffer) { + buffer += (sizeof(kd_chunk_header_v3) + sizeof(uint64_t)); + } - /* Disable entropy sampling */ - kdebug_enable &= ~KDEBUG_ENABLE_ENTROPY; - kdebug_slowcheck &= ~SLOW_ENTROPY; + assert(count >= (sizeof(kd_chunk_header_v3) + sizeof(uint64_t))); + count -= (sizeof(kd_chunk_header_v3) + sizeof(uint64_t)); + *number += (sizeof(kd_chunk_header_v3) + sizeof(uint64_t)); + } + if (vp) { + size_t write_size = tempbuf_number * sizeof(kd_buf); + error = kdbg_write_to_vnode((caddr_t)kdcopybuf, write_size, vp, ctx, RAW_file_offset); + if (!error) { + RAW_file_offset += write_size; + } - *number = 0; - ret = 0; + if (RAW_file_written >= RAW_FLUSH_SIZE) { + error = VNOP_FSYNC(vp, MNT_NOWAIT, ctx); - if (kd_entropy_indx > 0) - { - /* copyout the buffer */ - if (copyout(kd_entropy_buffer, buffer, kd_entropy_indx * sizeof(mach_timespec_t))) - ret = EINVAL; - else - *number = kd_entropy_indx; - } + RAW_file_written = 0; + } + } else { + error = copyout(kdcopybuf, buffer, tempbuf_number * sizeof(kd_buf)); + buffer += (tempbuf_number * sizeof(kd_buf)); + } +check_error: + if (error) { + *number = 0; + error = EINVAL; + break; + } + count -= tempbuf_number; + *number += tempbuf_number; + } + if (out_of_events == true) { + /* + * all trace buffers are empty + */ + break; + } - /* Always cleanup */ - kd_entropy_count = 0; - kd_entropy_indx = 0; - kd_entropy_buftomem = 0; - kmem_free(kernel_map, (vm_offset_t)kd_entropy_buffer, kd_entropy_bufsize); - kd_entropy_buffer = (uint64_t *) 0; - return(ret); + if ((tempbuf_count = count) > KDCOPYBUF_COUNT) { + tempbuf_count = KDCOPYBUF_COUNT; + } + } + if (!(old_kdebug_flags & KDBG_NOWRAP)) { + enable_wrap(old_kdebug_slowcheck); + } + thread_clear_eager_preempt(current_thread()); + return error; } +#define KDEBUG_TEST_CODE(code) BSDDBG_CODE(DBG_BSD_KDEBUG_TEST, (code)) + +/* + * A test IOP for the SYNC_FLUSH callback. + */ + +static int sync_flush_iop = 0; static void -kdbg_set_nkdbufs(unsigned int value) +sync_flush_callback(void * __unused context, kd_callback_type reason, + void * __unused arg) { - /* - * We allow a maximum buffer size of 25% of either ram or max mapped address, whichever is smaller - * 'value' is the desired number of trace entries - */ - unsigned int max_entries = (sane_size/4) / sizeof(kd_buf); + assert(sync_flush_iop > 0); - if (value <= max_entries) - nkdbufs = value; - else - nkdbufs = max_entries; + if (reason == KD_CALLBACK_SYNC_FLUSH) { + kernel_debug_enter(sync_flush_iop, KDEBUG_TEST_CODE(0xff), + kdbg_timestamp(), 0, 0, 0, 0, 0); + } } +static struct kd_callback sync_flush_kdcb = { + .func = sync_flush_callback, + .iop_name = "test_sf", +}; -/* - * This function is provided for the CHUD toolkit only. - * int val: - * zero disables kdebug_chudhook function call - * non-zero enables kdebug_chudhook function call - * char *fn: - * address of the enabled kdebug_chudhook function -*/ +static int +kdbg_test(size_t flavor) +{ + int code = 0; + int dummy_iop = 0; + + switch (flavor) { + case 1: + /* try each macro */ + KDBG(KDEBUG_TEST_CODE(code)); code++; + KDBG(KDEBUG_TEST_CODE(code), 1); code++; + KDBG(KDEBUG_TEST_CODE(code), 1, 2); code++; + KDBG(KDEBUG_TEST_CODE(code), 1, 2, 3); code++; + KDBG(KDEBUG_TEST_CODE(code), 1, 2, 3, 4); code++; + + KDBG_RELEASE(KDEBUG_TEST_CODE(code)); code++; + KDBG_RELEASE(KDEBUG_TEST_CODE(code), 1); code++; + KDBG_RELEASE(KDEBUG_TEST_CODE(code), 1, 2); code++; + KDBG_RELEASE(KDEBUG_TEST_CODE(code), 1, 2, 3); code++; + KDBG_RELEASE(KDEBUG_TEST_CODE(code), 1, 2, 3, 4); code++; + + KDBG_FILTERED(KDEBUG_TEST_CODE(code)); code++; + KDBG_FILTERED(KDEBUG_TEST_CODE(code), 1); code++; + KDBG_FILTERED(KDEBUG_TEST_CODE(code), 1, 2); code++; + KDBG_FILTERED(KDEBUG_TEST_CODE(code), 1, 2, 3); code++; + KDBG_FILTERED(KDEBUG_TEST_CODE(code), 1, 2, 3, 4); code++; + + KDBG_RELEASE_NOPROCFILT(KDEBUG_TEST_CODE(code)); code++; + KDBG_RELEASE_NOPROCFILT(KDEBUG_TEST_CODE(code), 1); code++; + KDBG_RELEASE_NOPROCFILT(KDEBUG_TEST_CODE(code), 1, 2); code++; + KDBG_RELEASE_NOPROCFILT(KDEBUG_TEST_CODE(code), 1, 2, 3); code++; + KDBG_RELEASE_NOPROCFILT(KDEBUG_TEST_CODE(code), 1, 2, 3, 4); code++; + + KDBG_DEBUG(KDEBUG_TEST_CODE(code)); code++; + KDBG_DEBUG(KDEBUG_TEST_CODE(code), 1); code++; + KDBG_DEBUG(KDEBUG_TEST_CODE(code), 1, 2); code++; + KDBG_DEBUG(KDEBUG_TEST_CODE(code), 1, 2, 3); code++; + KDBG_DEBUG(KDEBUG_TEST_CODE(code), 1, 2, 3, 4); code++; + break; + + case 2: + if (kd_ctrl_page.kdebug_iops) { + /* avoid the assertion in kernel_debug_enter for a valid IOP */ + dummy_iop = kd_ctrl_page.kdebug_iops[0].cpu_id; + } + + /* ensure old timestamps are not emitted from kernel_debug_enter */ + kernel_debug_enter(dummy_iop, KDEBUG_TEST_CODE(code), + 100 /* very old timestamp */, 0, 0, 0, 0, 0); + code++; + kernel_debug_enter(dummy_iop, KDEBUG_TEST_CODE(code), + kdbg_timestamp(), 0, 0, 0, 0, 0); + code++; + break; + + case 3: + if (kd_ctrl_page.kdebug_iops) { + dummy_iop = kd_ctrl_page.kdebug_iops[0].cpu_id; + } + kernel_debug_enter(dummy_iop, KDEBUG_TEST_CODE(code), + kdbg_timestamp() * 2 /* !!! */, 0, 0, 0, 0, 0); + break; + + case 4: + if (!sync_flush_iop) { + sync_flush_iop = kernel_debug_register_callback( + sync_flush_kdcb); + assert(sync_flush_iop > 0); + } + break; + + default: + return ENOTSUP; + } + + return 0; +} + +#undef KDEBUG_TEST_CODE void -kdbg_control_chud(int val, void *fn) +kdebug_init(unsigned int n_events, char *filter_desc, bool wrapping) { - if (val) { - /* enable chudhook */ - kdebug_chudhook = fn; - kdebug_enable |= KDEBUG_ENABLE_CHUD; + assert(filter_desc != NULL); + +#if defined(__x86_64__) + /* only trace MACH events when outputting kdebug to serial */ + if (kdebug_serial) { + n_events = 1; + if (filter_desc[0] == '\0') { + filter_desc[0] = 'C'; + filter_desc[1] = '1'; + filter_desc[2] = '\0'; + } } - else { - /* disable chudhook */ - kdebug_enable &= ~KDEBUG_ENABLE_CHUD; - kdebug_chudhook = 0; +#endif /* defined(__x86_64__) */ + + if (log_leaks && n_events == 0) { + n_events = 200000; } + + kdebug_trace_start(n_events, filter_desc, wrapping, false); } - -int -kdbg_control(int *name, u_int namelen, user_addr_t where, size_t *sizep) +static void +kdbg_set_typefilter_string(const char *filter_desc) { - int ret=0; - size_t size=*sizep; - unsigned int value = 0; - kd_regtype kd_Reg; - kbufinfo_t kd_bufinfo; - pid_t curpid; - struct proc *p, *curproc; - - if (name[0] == KERN_KDGETENTROPY || - name[0] == KERN_KDEFLAGS || - name[0] == KERN_KDDFLAGS || - name[0] == KERN_KDENABLE || - name[0] == KERN_KDSETBUF) { - - if ( namelen < 2 ) - return(EINVAL); - value = name[1]; - } - - kdbg_lock_init(); + char *end = NULL; - if ( !(kdebug_flags & KDBG_LOCKINIT)) - return(ENOMEM); + ktrace_assert_lock_held(); - lck_mtx_lock(kd_trace_mtx_sysctl); + assert(filter_desc != NULL); - if (name[0] == KERN_KDGETBUF) { - /* - * Does not alter the global_state_pid - * This is a passive request. - */ - if (size < sizeof(kd_bufinfo.nkdbufs)) { - /* - * There is not enough room to return even - * the first element of the info structure. - */ - lck_mtx_unlock(kd_trace_mtx_sysctl); - - return(EINVAL); - } - kd_bufinfo.nkdbufs = nkdbufs; - kd_bufinfo.nkdthreads = kd_mapsize / sizeof(kd_threadmap); - - if ( (kdebug_slowcheck & SLOW_NOLOG) ) - kd_bufinfo.nolog = 1; - else - kd_bufinfo.nolog = 0; - kd_bufinfo.flags = kdebug_flags; - kd_bufinfo.bufid = global_state_pid; - - if (size >= sizeof(kd_bufinfo)) { - /* - * Provide all the info we have - */ - if (copyout (&kd_bufinfo, where, sizeof(kd_bufinfo))) { - lck_mtx_unlock(kd_trace_mtx_sysctl); - - return(EINVAL); - } - } - else { - /* - * For backwards compatibility, only provide - * as much info as there is room for. - */ - if (copyout (&kd_bufinfo, where, size)) { - lck_mtx_unlock(kd_trace_mtx_sysctl); - - return(EINVAL); - } - } - lck_mtx_unlock(kd_trace_mtx_sysctl); - - return(0); - } else if (name[0] == KERN_KDGETENTROPY) { - if (kd_entropy_buffer) - ret = EBUSY; - else - ret = kdbg_getentropy(where, sizep, value); - lck_mtx_unlock(kd_trace_mtx_sysctl); - - return (ret); - } - - if ((curproc = current_proc()) != NULL) - curpid = curproc->p_pid; - else { - lck_mtx_unlock(kd_trace_mtx_sysctl); - - return (ESRCH); - } - if (global_state_pid == -1) - global_state_pid = curpid; - else if (global_state_pid != curpid) { - if ((p = proc_find(global_state_pid)) == NULL) { - /* - * The global pid no longer exists - */ - global_state_pid = curpid; - } else { - /* - * The global pid exists, deny this request - */ - proc_rele(p); - lck_mtx_unlock(kd_trace_mtx_sysctl); + typefilter_reject_all(kdbg_typefilter); + typefilter_allow_class(kdbg_typefilter, DBG_TRACE); - return(EBUSY); - } + /* if the filter description starts with a number, assume it's a csc */ + if (filter_desc[0] >= '0' && filter_desc[0] <= '9') { + unsigned long csc = strtoul(filter_desc, NULL, 0); + if (filter_desc != end && csc <= KDBG_CSC_MAX) { + typefilter_allow_csc(kdbg_typefilter, csc); + } + return; } - switch(name[0]) { - case KERN_KDEFLAGS: - value &= KDBG_USERFLAGS; - kdebug_flags |= value; - break; - case KERN_KDDFLAGS: - value &= KDBG_USERFLAGS; - kdebug_flags &= ~value; - break; - case KERN_KDENABLE: /* used to enable or disable */ - if (value) - { - /* enable only if buffer is initialized */ - if (!(kdebug_flags & KDBG_BUFINIT)) - { - ret=EINVAL; - break; - } - kdbg_mapinit(); - - kdebug_enable |= KDEBUG_ENABLE_TRACE; - kdebug_slowcheck &= ~SLOW_NOLOG; - } - else - { - kdebug_enable &= ~KDEBUG_ENABLE_TRACE; - kdebug_slowcheck |= SLOW_NOLOG; - } - break; - case KERN_KDSETBUF: - kdbg_set_nkdbufs(value); - break; - case KERN_KDSETUP: - ret=kdbg_reinit(); - break; - case KERN_KDREMOVE: - kdbg_clear(); - break; - case KERN_KDSETREG: - if(size < sizeof(kd_regtype)) { - ret=EINVAL; - break; - } - if (copyin(where, &kd_Reg, sizeof(kd_regtype))) { - ret= EINVAL; - break; - } - ret = kdbg_setreg(&kd_Reg); - break; - case KERN_KDGETREG: - if(size < sizeof(kd_regtype)) { - ret = EINVAL; - break; - } - ret = kdbg_getreg(&kd_Reg); - if (copyout(&kd_Reg, where, sizeof(kd_regtype))){ - ret=EINVAL; - } - break; - case KERN_KDREADTR: - ret = kdbg_read(where, sizep); - break; - case KERN_KDPIDTR: - if (size < sizeof(kd_regtype)) { - ret = EINVAL; - break; - } - if (copyin(where, &kd_Reg, sizeof(kd_regtype))) { - ret= EINVAL; - break; - } - ret = kdbg_setpid(&kd_Reg); - break; - case KERN_KDPIDEX: - if (size < sizeof(kd_regtype)) { - ret = EINVAL; - break; - } - if (copyin(where, &kd_Reg, sizeof(kd_regtype))) { - ret= EINVAL; - break; + while (filter_desc[0] != '\0') { + unsigned long allow_value; + + char filter_type = filter_desc[0]; + if (filter_type != 'C' && filter_type != 'S') { + return; + } + filter_desc++; + + allow_value = strtoul(filter_desc, &end, 0); + if (filter_desc == end) { + /* cannot parse as integer */ + return; + } + + switch (filter_type) { + case 'C': + if (allow_value <= KDBG_CLASS_MAX) { + typefilter_allow_class(kdbg_typefilter, allow_value); + } else { + /* illegal class */ + return; } - ret = kdbg_setpidex(&kd_Reg); break; - case KERN_KDTHRMAP: - ret = kdbg_readmap(where, sizep); - break; - case KERN_KDSETRTCDEC: - if (size < sizeof(kd_regtype)) { - ret = EINVAL; - break; - } - if (copyin(where, &kd_Reg, sizeof(kd_regtype))) { - ret= EINVAL; - break; + case 'S': + if (allow_value <= KDBG_CSC_MAX) { + typefilter_allow_csc(kdbg_typefilter, allow_value); + } else { + /* illegal class subclass */ + return; } - ret = kdbg_setrtcdec(&kd_Reg); break; - default: - ret= EINVAL; - } - lck_mtx_unlock(kd_trace_mtx_sysctl); + return; + } - return(ret); + /* advance to next filter entry */ + filter_desc = end; + if (filter_desc[0] == ',') { + filter_desc++; + } + } } - /* - * This code can run concurrently with kernel_debug_internal() - * without the need of any locks, because all reads of kd_bufptr[i], - * which get modified by kernel_debug_internal(), are safe. + * This function is meant to be called from the bootstrap thread or coming out + * of acpi_idle_kernel. */ -int -kdbg_read(user_addr_t buffer, size_t *number) +void +kdebug_trace_start(unsigned int n_events, const char *filter_desc, + bool wrapping, bool at_wake) { - unsigned int count; - unsigned int cpu; - int mincpu; - uint64_t mintime, t, last_wrap_time; - int last_wrap_cpu; - int error = 0; - kd_buf *tempbuf; - uint32_t tempbuf_count; - uint32_t tempbuf_number; - unsigned int old_kdebug_flags, new_kdebug_flags; - unsigned int old_kdebug_slowcheck, new_kdebug_slowcheck; - boolean_t first_event = TRUE; + if (!n_events) { + kd_early_done = true; + return; + } - count = *number/sizeof(kd_buf); - *number = 0; + ktrace_start_single_threaded(); - if (count == 0 || !(kdebug_flags & KDBG_BUFINIT) || kdcopybuf == 0) - return EINVAL; + kdbg_lock_init(); - /* - * because we hold kd_trace_mtx_sysctl, no other control threads can - * be playing with kdebug_flags... the code that cuts new events could - * be running, but it only reads kdebug_flags, it doesn't write it.. - * use an OSCompareAndSwap to make sure the other processors see the - * change of state immediately, not to protect against 2 threads racing to update it - */ - old_kdebug_slowcheck = kdebug_slowcheck; - do { - old_kdebug_flags = kdebug_flags; - new_kdebug_flags = old_kdebug_flags & ~KDBG_WRAPPED; - new_kdebug_flags |= KDBG_NOWRAP; - } while ( !OSCompareAndSwap((UInt32)old_kdebug_flags, (UInt32)new_kdebug_flags, (UInt32 *)&kdebug_flags)); - - last_wrap_time = 0; - last_wrap_cpu = -1; - - for (cpu = 0; cpu < kd_cpus; cpu++) { - kd_buf *cur_bufptr; - - if ((cur_bufptr = kdbip[cpu].kd_bufptr) >= kdbip[cpu].kd_buflast) - cur_bufptr = kdbip[cpu].kd_buffer; - - if (kdbip[cpu].kd_wrapped) { - kdbip[cpu].kd_wrapped = 0; - kdbip[cpu].kd_readlast = cur_bufptr; - kdbip[cpu].kd_stop = cur_bufptr; - - if (kd_cpus > 1 && ((cur_bufptr->timestamp & KDBG_TIMESTAMP_MASK) > last_wrap_time)) { - last_wrap_time = cur_bufptr->timestamp & KDBG_TIMESTAMP_MASK; - last_wrap_cpu = cpu; - } - } else { - if (kdbip[cpu].kd_readlast == cur_bufptr) - kdbip[cpu].kd_stop = 0; - else - kdbip[cpu].kd_stop = cur_bufptr; - } - } - if (count > nkdbufs) - count = nkdbufs; + ktrace_kernel_configure(KTRACE_KDEBUG); - if ((tempbuf_count = count) > KDCOPYBUF_COUNT) - tempbuf_count = KDCOPYBUF_COUNT; + kdbg_set_nkdbufs(n_events); - if (last_wrap_cpu == -1) - first_event = FALSE; + kernel_debug_string_early("start_kern_tracing"); - while (count) { - tempbuf = kdcopybuf; - tempbuf_number = 0; + if (kdbg_reinit(true)) { + printf("error from kdbg_reinit, kernel tracing not started\n"); + goto out; + } - while (tempbuf_count) { - mintime = 0xffffffffffffffffULL; /* all actual timestamps are below */ - mincpu = -1; + /* + * Wrapping is disabled because boot and wake tracing is interested in + * the earliest events, at the expense of later ones. + */ + if (!wrapping) { + uint32_t old1, old2; + (void)disable_wrap(&old1, &old2); + } - for (cpu = 0; cpu < kd_cpus; cpu++) { - if (kdbip[cpu].kd_stop == 0) /* empty buffer */ - continue; - t = kdbip[cpu].kd_readlast[0].timestamp & KDBG_TIMESTAMP_MASK; + if (filter_desc && filter_desc[0] != '\0') { + if (kdbg_initialize_typefilter(NULL) == KERN_SUCCESS) { + kdbg_set_typefilter_string(filter_desc); + kdbg_enable_typefilter(); + } + } - if (t < mintime) { - mintime = t; - mincpu = cpu; - } - } - if (mincpu < 0) - /* - * all buffers ran empty early - */ - break; + /* + * Hold off interrupts between getting a thread map and enabling trace + * and until the early traces are recorded. + */ + bool s = ml_set_interrupts_enabled(false); - if (first_event == TRUE) { - /* - * make sure we leave room for the - * LAST_WRAPPER event we inject - * by throwing away the first event - * it's better to lose that one - * than the last one - */ - first_event = FALSE; + if (at_wake) { + kdbg_thrmap_init(); + } - kdbip[mincpu].kd_readlast++; + kdbg_set_tracing_enabled(true, KDEBUG_ENABLE_TRACE | (kdebug_serial ? + KDEBUG_ENABLE_SERIAL : 0)); - if (kdbip[mincpu].kd_readlast == kdbip[mincpu].kd_buflast) - kdbip[mincpu].kd_readlast = kdbip[mincpu].kd_buffer; - if (kdbip[mincpu].kd_readlast == kdbip[mincpu].kd_stop) - kdbip[mincpu].kd_stop = 0; + if (!at_wake) { + /* + * Transfer all very early events from the static buffer into the real + * buffers. + */ + kernel_debug_early_end(); + } - continue; - } - if (last_wrap_cpu == mincpu) { - tempbuf->debugid = MISCDBG_CODE(DBG_BUFFER, 0) | DBG_FUNC_NONE; - tempbuf->arg1 = kd_bufsize / sizeof(kd_buf); - tempbuf->arg2 = kd_cpus; - tempbuf->arg3 = 0; - tempbuf->arg4 = 0; - tempbuf->arg5 = (int)current_thread(); - - tempbuf->timestamp = last_wrap_time | (((uint64_t)last_wrap_cpu) << KDBG_CPU_SHIFT); + ml_set_interrupts_enabled(s); - tempbuf++; + printf("kernel tracing started with %u events\n", n_events); - last_wrap_cpu = -1; +#if KDEBUG_MOJO_TRACE + if (kdebug_serial) { + printf("serial output enabled with %lu named events\n", + sizeof(kd_events) / sizeof(kd_event_t)); + } +#endif /* KDEBUG_MOJO_TRACE */ - } else { - *(tempbuf++) = kdbip[mincpu].kd_readlast[0]; +out: + ktrace_end_single_threaded(); +} - kdbip[mincpu].kd_readlast++; +void +kdbg_dump_trace_to_file(const char *filename) +{ + vfs_context_t ctx; + vnode_t vp; + size_t write_size; + int ret; - if (kdbip[mincpu].kd_readlast == kdbip[mincpu].kd_buflast) - kdbip[mincpu].kd_readlast = kdbip[mincpu].kd_buffer; - if (kdbip[mincpu].kd_readlast == kdbip[mincpu].kd_stop) - kdbip[mincpu].kd_stop = 0; - } - tempbuf_count--; - tempbuf_number++; - } - if (tempbuf_number) { - if ((error = copyout(kdcopybuf, buffer, tempbuf_number * sizeof(kd_buf)))) { - *number = 0; - error = EINVAL; - break; - } - count -= tempbuf_number; - *number += tempbuf_number; - buffer += (tempbuf_number * sizeof(kd_buf)); - } - if (tempbuf_count) - /* - * all trace buffers are empty - */ - break; + ktrace_lock(); - if ((tempbuf_count = count) > KDCOPYBUF_COUNT) - tempbuf_count = KDCOPYBUF_COUNT; + if (!(kdebug_enable & KDEBUG_ENABLE_TRACE)) { + goto out; } - if ( !(old_kdebug_flags & KDBG_NOWRAP)) { - do { - old_kdebug_flags = kdebug_flags; - new_kdebug_flags = old_kdebug_flags & ~KDBG_NOWRAP; - } while ( !OSCompareAndSwap((UInt32)old_kdebug_flags, (UInt32)new_kdebug_flags, (UInt32 *)&kdebug_flags)); - if ( !(old_kdebug_slowcheck & SLOW_NOLOG)) { - do { - old_kdebug_slowcheck = kdebug_slowcheck; - new_kdebug_slowcheck = old_kdebug_slowcheck & ~SLOW_NOLOG; - } while ( !OSCompareAndSwap((UInt32)old_kdebug_slowcheck, (UInt32)new_kdebug_slowcheck, (UInt32 *)&kdebug_slowcheck)); - } + if (ktrace_get_owning_pid() != 0) { + /* + * Another process owns ktrace and is still active, disable tracing to + * prevent wrapping. + */ + kdebug_enable = 0; + kd_ctrl_page.enabled = 0; + commpage_update_kdebug_state(); + goto out; } - return (error); -} + KDBG_RELEASE(TRACE_WRITING_EVENTS | DBG_FUNC_START); -unsigned char *getProcName(struct proc *proc); -unsigned char *getProcName(struct proc *proc) { + kdebug_enable = 0; + kd_ctrl_page.enabled = 0; + commpage_update_kdebug_state(); - return (unsigned char *) &proc->p_comm; /* Return pointer to the proc name */ + ctx = vfs_context_kernel(); -} - -#define STACKSHOT_SUBSYS_LOCK() lck_mtx_lock(&stackshot_subsys_mutex) -#define STACKSHOT_SUBSYS_UNLOCK() lck_mtx_unlock(&stackshot_subsys_mutex) -#ifdef __i386__ -#define TRAP_DEBUGGER __asm__ volatile("int3"); -#endif -#ifdef __ppc__ -#define TRAP_DEBUGGER __asm__ volatile("tw 4,r3,r3"); -#endif + if (vnode_open(filename, (O_CREAT | FWRITE | O_NOFOLLOW), 0600, 0, &vp, ctx)) { + goto out; + } -#define SANE_TRACEBUF_SIZE 2*1024*1024 + kdbg_write_thread_map(vp, ctx); -/* Initialize the mutex governing access to the stack snapshot subsystem */ -__private_extern__ void -stackshot_lock_init( void ) -{ - stackshot_subsys_lck_grp_attr = lck_grp_attr_alloc_init(); + write_size = nkdbufs * sizeof(kd_buf); + ret = kdbg_read(0, &write_size, vp, ctx, RAW_VERSION1); + if (ret) { + goto out_close; + } - stackshot_subsys_lck_grp = lck_grp_alloc_init("stackshot_subsys_lock", stackshot_subsys_lck_grp_attr); + /* + * Wait to synchronize the file to capture the I/O in the + * TRACE_WRITING_EVENTS interval. + */ + ret = VNOP_FSYNC(vp, MNT_WAIT, ctx); - stackshot_subsys_lck_attr = lck_attr_alloc_init(); + /* + * Balance the starting TRACE_WRITING_EVENTS tracepoint manually. + */ + kd_buf end_event = { + .debugid = TRACE_WRITING_EVENTS | DBG_FUNC_END, + .arg1 = write_size, + .arg2 = ret, + .arg5 = thread_tid(current_thread()), + }; + kdbg_set_timestamp_and_cpu(&end_event, kdbg_timestamp(), + cpu_number()); + + /* this is best effort -- ignore any errors */ + (void)kdbg_write_to_vnode((caddr_t)&end_event, sizeof(kd_buf), vp, ctx, + RAW_file_offset); + +out_close: + vnode_close(vp, FWRITE, ctx); + sync(current_proc(), (void *)NULL, (int *)NULL); - lck_mtx_init(&stackshot_subsys_mutex, stackshot_subsys_lck_grp, stackshot_subsys_lck_attr); +out: + ktrace_unlock(); } -/* - * stack_snapshot: Obtains a coherent set of stack traces for all threads - * on the system, tracing both kernel and user stacks - * where available. Uses machine specific trace routines - * for ppc, ppc64 and x86. - * Inputs: uap->pid - process id of process to be traced, or -1 - * for the entire system - * uap->tracebuf - address of the user space destination - * buffer - * uap->tracebuf_size - size of the user space trace buffer - * uap->options - various options, including the maximum - * number of frames to trace. - * Outputs: EPERM if the caller is not privileged - * EINVAL if the supplied trace buffer isn't sanely sized - * ENOMEM if we don't have enough memory to satisfy the - * request - * ENOENT if the target pid isn't found - * ENOSPC if the supplied buffer is insufficient - * *retval contains the number of bytes traced, if successful - * and -1 otherwise. If the request failed due to - * tracebuffer exhaustion, we copyout as much as possible. - */ -int -stack_snapshot(struct proc *p, register struct stack_snapshot_args *uap, register_t *retval) { - int error = 0; +static int +kdbg_sysctl_continuous SYSCTL_HANDLER_ARGS +{ +#pragma unused(oidp, arg1, arg2) + int value = kdbg_continuous_time; + int ret = sysctl_io_number(req, value, sizeof(value), &value, NULL); - if ((error = suser(kauth_cred_get(), &p->p_acflag))) - return(error); + if (ret || !req->newptr) { + return ret; + } - return stack_snapshot2(uap->pid, uap->tracebuf, uap->tracebuf_size, - uap->options, retval); + kdbg_continuous_time = value; + return 0; } -int -stack_snapshot2(pid_t pid, user_addr_t tracebuf, uint32_t tracebuf_size, uint32_t options, register_t *retval) -{ - int error = 0; - unsigned bytesTraced = 0; +SYSCTL_NODE(_kern, OID_AUTO, kdbg, CTLFLAG_RD | CTLFLAG_LOCKED, 0, + "kdbg"); - *retval = -1; -/* Serialize tracing */ - STACKSHOT_SUBSYS_LOCK(); - - if ((tracebuf_size <= 0) || (tracebuf_size > SANE_TRACEBUF_SIZE)) { - error = EINVAL; - goto error_exit; - } +SYSCTL_PROC(_kern_kdbg, OID_AUTO, experimental_continuous, + CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, 0, + sizeof(int), kdbg_sysctl_continuous, "I", + "Set kdebug to use mach_continuous_time"); - MALLOC(stackshot_snapbuf, void *, tracebuf_size, M_TEMP, M_WAITOK); +SYSCTL_INT(_kern_kdbg, OID_AUTO, debug, + CTLFLAG_RW | CTLFLAG_LOCKED, + &kdbg_debug, 0, "Set kdebug debug mode"); - if (stackshot_snapbuf == NULL) { - error = ENOMEM; - goto error_exit; +SYSCTL_QUAD(_kern_kdbg, OID_AUTO, oldest_time, + CTLTYPE_QUAD | CTLFLAG_RD | CTLFLAG_LOCKED, + &kd_ctrl_page.oldest_time, + "Find the oldest timestamp still in trace"); + +#if KDEBUG_MOJO_TRACE +static kd_event_t * +binary_search(uint32_t id) +{ + int low, high, mid; + + low = 0; + high = (int)(sizeof(kd_events) / sizeof(kd_event_t)) - 1; + + while (true) { + mid = (low + high) / 2; + + if (low > high) { + return NULL; /* failed */ + } else if (low + 1 >= high) { + /* We have a match */ + if (kd_events[high].id == id) { + return &kd_events[high]; + } else if (kd_events[low].id == id) { + return &kd_events[low]; + } else { + return NULL; /* search failed */ + } + } else if (id < kd_events[mid].id) { + high = mid; + } else { + low = mid; + } } -/* Preload trace parameters*/ - kdp_snapshot_preflight(pid, stackshot_snapbuf, tracebuf_size, options); +} -/* Trap to the debugger to obtain a coherent stack snapshot; this populates - * the trace buffer +/* + * Look up event id to get name string. + * Using a per-cpu cache of a single entry + * before resorting to a binary search of the full table. */ - if (panic_active()) { - error = ENOMEM; - goto error_exit; +#define NCACHE 1 +static kd_event_t *last_hit[MAX_CPUS]; +static kd_event_t * +event_lookup_cache(uint32_t cpu, uint32_t id) +{ + if (last_hit[cpu] == NULL || last_hit[cpu]->id != id) { + last_hit[cpu] = binary_search(id); } + return last_hit[cpu]; +} - TRAP_DEBUGGER; +static uint64_t kd_last_timstamp; - bytesTraced = kdp_stack_snapshot_bytes_traced(); - - if (bytesTraced > 0) { - if ((error = copyout(stackshot_snapbuf, tracebuf, - ((bytesTraced < tracebuf_size) ? - bytesTraced : tracebuf_size)))) - goto error_exit; - *retval = bytesTraced; +static void +kdebug_serial_print( + uint32_t cpunum, + uint32_t debugid, + uint64_t timestamp, + uintptr_t arg1, + uintptr_t arg2, + uintptr_t arg3, + uintptr_t arg4, + uintptr_t threadid + ) +{ + char kprintf_line[192]; + char event[40]; + uint64_t us = timestamp / NSEC_PER_USEC; + uint64_t us_tenth = (timestamp % NSEC_PER_USEC) / 100; + uint64_t delta = timestamp - kd_last_timstamp; + uint64_t delta_us = delta / NSEC_PER_USEC; + uint64_t delta_us_tenth = (delta % NSEC_PER_USEC) / 100; + uint32_t event_id = debugid & KDBG_EVENTID_MASK; + const char *command; + const char *bra; + const char *ket; + kd_event_t *ep; + + /* event time and delta from last */ + snprintf(kprintf_line, sizeof(kprintf_line), + "%11llu.%1llu %8llu.%1llu ", + us, us_tenth, delta_us, delta_us_tenth); + + + /* event (id or name) - start prefixed by "[", end postfixed by "]" */ + bra = (debugid & DBG_FUNC_START) ? "[" : " "; + ket = (debugid & DBG_FUNC_END) ? "]" : " "; + ep = event_lookup_cache(cpunum, event_id); + if (ep) { + if (strlen(ep->name) < sizeof(event) - 3) { + snprintf(event, sizeof(event), "%s%s%s", + bra, ep->name, ket); + } else { + snprintf(event, sizeof(event), "%s%x(name too long)%s", + bra, event_id, ket); + } + } else { + snprintf(event, sizeof(event), "%s%x%s", + bra, event_id, ket); } - else { - error = ENOENT; - goto error_exit; + snprintf(kprintf_line + strlen(kprintf_line), + sizeof(kprintf_line) - strlen(kprintf_line), + "%-40s ", event); + + /* arg1 .. arg4 with special cases for strings */ + switch (event_id) { + case VFS_LOOKUP: + case VFS_LOOKUP_DONE: + if (debugid & DBG_FUNC_START) { + /* arg1 hex then arg2..arg4 chars */ + snprintf(kprintf_line + strlen(kprintf_line), + sizeof(kprintf_line) - strlen(kprintf_line), + "%-16lx %-8s%-8s%-8s ", + arg1, (char*)&arg2, (char*)&arg3, (char*)&arg4); + break; + } + /* else fall through for arg1..arg4 chars */ + case TRACE_STRING_EXEC: + case TRACE_STRING_NEWTHREAD: + case TRACE_INFO_STRING: + snprintf(kprintf_line + strlen(kprintf_line), + sizeof(kprintf_line) - strlen(kprintf_line), + "%-8s%-8s%-8s%-8s ", + (char*)&arg1, (char*)&arg2, (char*)&arg3, (char*)&arg4); + break; + default: + snprintf(kprintf_line + strlen(kprintf_line), + sizeof(kprintf_line) - strlen(kprintf_line), + "%-16lx %-16lx %-16lx %-16lx", + arg1, arg2, arg3, arg4); } - error = kdp_stack_snapshot_geterror(); - if (error == -1) { - error = ENOSPC; - *retval = -1; - goto error_exit; + /* threadid, cpu and command name */ + if (threadid == (uintptr_t)thread_tid(current_thread()) && + current_proc() && + current_proc()->p_comm[0]) { + command = current_proc()->p_comm; + } else { + command = "-"; } + snprintf(kprintf_line + strlen(kprintf_line), + sizeof(kprintf_line) - strlen(kprintf_line), + " %-16lx %-2d %s\n", + threadid, cpunum, command); -error_exit: - if (stackshot_snapbuf != NULL) - FREE(stackshot_snapbuf, M_TEMP); - stackshot_snapbuf = NULL; - STACKSHOT_SUBSYS_UNLOCK(); - return error; + kprintf("%s", kprintf_line); + kd_last_timstamp = timestamp; } -void -start_kern_tracing(unsigned int new_nkdbufs) { - if (!new_nkdbufs) - return; - kdbg_set_nkdbufs(new_nkdbufs); - kdbg_lock_init(); - kdbg_reinit(); - kdebug_enable |= KDEBUG_ENABLE_TRACE; - kdebug_slowcheck &= ~SLOW_NOLOG; - kdbg_mapinit(); - printf("kernel tracing started\n"); -} +#endif