X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=kernel%2Fkprobes.c;h=6c86d67ed1a71aba7063b26c37afd6c7a40aa911;hb=e3869792990f708c97be5877499cada70d469bd3;hp=17ec4afb0994e48adc1c7a9cfde971f04b08d512;hpb=e9ccb79927225d8cd8d022a7c09bfb2fad935b89;p=deliverable%2Flinux.git diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 17ec4afb0994..6c86d67ed1a7 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -35,10 +35,13 @@ #include #include #include +#include #include #include #include #include +#include +#include #include #include #include @@ -87,6 +90,12 @@ struct kprobe_insn_page { int ngarbage; }; +enum kprobe_slot_state { + SLOT_CLEAN = 0, + SLOT_DIRTY = 1, + SLOT_USED = 2, +}; + static struct hlist_head kprobe_insn_pages; static int kprobe_garbage_slots; static int collect_garbage_slots(void); @@ -130,8 +139,8 @@ kprobe_opcode_t __kprobes *get_insn_slot(void) if (kip->nused < INSNS_PER_PAGE) { int i; for (i = 0; i < INSNS_PER_PAGE; i++) { - if (!kip->slot_used[i]) { - kip->slot_used[i] = 1; + if (kip->slot_used[i] == SLOT_CLEAN) { + kip->slot_used[i] = SLOT_USED; kip->nused++; return kip->insns + (i * MAX_INSN_SIZE); } @@ -163,8 +172,8 @@ kprobe_opcode_t __kprobes *get_insn_slot(void) } INIT_HLIST_NODE(&kip->hlist); hlist_add_head(&kip->hlist, &kprobe_insn_pages); - memset(kip->slot_used, 0, INSNS_PER_PAGE); - kip->slot_used[0] = 1; + memset(kip->slot_used, SLOT_CLEAN, INSNS_PER_PAGE); + kip->slot_used[0] = SLOT_USED; kip->nused = 1; kip->ngarbage = 0; return kip->insns; @@ -173,7 +182,7 @@ kprobe_opcode_t __kprobes *get_insn_slot(void) /* Return 1 if all garbages are collected, otherwise 0. */ static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx) { - kip->slot_used[idx] = 0; + kip->slot_used[idx] = SLOT_CLEAN; kip->nused--; if (kip->nused == 0) { /* @@ -212,7 +221,7 @@ static int __kprobes collect_garbage_slots(void) continue; kip->ngarbage = 0; /* we will collect all garbages */ for (i = 0; i < INSNS_PER_PAGE; i++) { - if (kip->slot_used[i] == -1 && + if (kip->slot_used[i] == SLOT_DIRTY && collect_one_slot(kip, i)) break; } @@ -232,7 +241,7 @@ void __kprobes free_insn_slot(kprobe_opcode_t * slot, int dirty) slot < kip->insns + (INSNS_PER_PAGE * MAX_INSN_SIZE)) { int i = (slot - kip->insns) / MAX_INSN_SIZE; if (dirty) { - kip->slot_used[i] = -1; + kip->slot_used[i] = SLOT_DIRTY; kip->ngarbage++; } else { collect_one_slot(kip, i); @@ -772,6 +781,12 @@ int __kprobes register_kretprobe(struct kretprobe *rp) return -ENOSYS; } +static int __kprobes pre_handler_kretprobe(struct kprobe *p, + struct pt_regs *regs) +{ + return 0; +} + #endif /* ARCH_SUPPORTS_KRETPROBES */ void __kprobes unregister_kretprobe(struct kretprobe *rp) @@ -809,7 +824,109 @@ static int __init init_kprobes(void) return err; } -__initcall(init_kprobes); +#ifdef CONFIG_DEBUG_FS +static void __kprobes report_probe(struct seq_file *pi, struct kprobe *p, + const char *sym, int offset,char *modname) +{ + char *kprobe_type; + + if (p->pre_handler == pre_handler_kretprobe) + kprobe_type = "r"; + else if (p->pre_handler == setjmp_pre_handler) + kprobe_type = "j"; + else + kprobe_type = "k"; + if (sym) + seq_printf(pi, "%p %s %s+0x%x %s\n", p->addr, kprobe_type, + sym, offset, (modname ? modname : " ")); + else + seq_printf(pi, "%p %s %p\n", p->addr, kprobe_type, p->addr); +} + +static void __kprobes *kprobe_seq_start(struct seq_file *f, loff_t *pos) +{ + return (*pos < KPROBE_TABLE_SIZE) ? pos : NULL; +} + +static void __kprobes *kprobe_seq_next(struct seq_file *f, void *v, loff_t *pos) +{ + (*pos)++; + if (*pos >= KPROBE_TABLE_SIZE) + return NULL; + return pos; +} + +static void __kprobes kprobe_seq_stop(struct seq_file *f, void *v) +{ + /* Nothing to do */ +} + +static int __kprobes show_kprobe_addr(struct seq_file *pi, void *v) +{ + struct hlist_head *head; + struct hlist_node *node; + struct kprobe *p, *kp; + const char *sym = NULL; + unsigned int i = *(loff_t *) v; + unsigned long size, offset = 0; + char *modname, namebuf[128]; + + head = &kprobe_table[i]; + preempt_disable(); + hlist_for_each_entry_rcu(p, node, head, hlist) { + sym = kallsyms_lookup((unsigned long)p->addr, &size, + &offset, &modname, namebuf); + if (p->pre_handler == aggr_pre_handler) { + list_for_each_entry_rcu(kp, &p->list, list) + report_probe(pi, kp, sym, offset, modname); + } else + report_probe(pi, p, sym, offset, modname); + } + preempt_enable(); + return 0; +} + +static struct seq_operations kprobes_seq_ops = { + .start = kprobe_seq_start, + .next = kprobe_seq_next, + .stop = kprobe_seq_stop, + .show = show_kprobe_addr +}; + +static int __kprobes kprobes_open(struct inode *inode, struct file *filp) +{ + return seq_open(filp, &kprobes_seq_ops); +} + +static struct file_operations debugfs_kprobes_operations = { + .open = kprobes_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __kprobes debugfs_kprobe_init(void) +{ + struct dentry *dir, *file; + + dir = debugfs_create_dir("kprobes", NULL); + if (!dir) + return -ENOMEM; + + file = debugfs_create_file("list", 0444, dir, NULL, + &debugfs_kprobes_operations); + if (!file) { + debugfs_remove(dir); + return -ENOMEM; + } + + return 0; +} + +late_initcall(debugfs_kprobe_init); +#endif /* CONFIG_DEBUG_FS */ + +module_init(init_kprobes); EXPORT_SYMBOL_GPL(register_kprobe); EXPORT_SYMBOL_GPL(unregister_kprobe); @@ -818,4 +935,3 @@ EXPORT_SYMBOL_GPL(unregister_jprobe); EXPORT_SYMBOL_GPL(jprobe_return); EXPORT_SYMBOL_GPL(register_kretprobe); EXPORT_SYMBOL_GPL(unregister_kretprobe); -