diff options
Diffstat (limited to 'kernel/kprobes.c')
-rw-r--r-- | kernel/kprobes.c | 30 |
1 files changed, 11 insertions, 19 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 16b5739c516a..6fe9dc6d1a81 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c | |||
@@ -103,7 +103,7 @@ static struct kprobe_blackpoint kprobe_blacklist[] = { | |||
103 | #define INSNS_PER_PAGE (PAGE_SIZE/(MAX_INSN_SIZE * sizeof(kprobe_opcode_t))) | 103 | #define INSNS_PER_PAGE (PAGE_SIZE/(MAX_INSN_SIZE * sizeof(kprobe_opcode_t))) |
104 | 104 | ||
105 | struct kprobe_insn_page { | 105 | struct kprobe_insn_page { |
106 | struct hlist_node hlist; | 106 | struct list_head list; |
107 | kprobe_opcode_t *insns; /* Page of instruction slots */ | 107 | kprobe_opcode_t *insns; /* Page of instruction slots */ |
108 | char slot_used[INSNS_PER_PAGE]; | 108 | char slot_used[INSNS_PER_PAGE]; |
109 | int nused; | 109 | int nused; |
@@ -117,7 +117,7 @@ enum kprobe_slot_state { | |||
117 | }; | 117 | }; |
118 | 118 | ||
119 | static DEFINE_MUTEX(kprobe_insn_mutex); /* Protects kprobe_insn_pages */ | 119 | static DEFINE_MUTEX(kprobe_insn_mutex); /* Protects kprobe_insn_pages */ |
120 | static struct hlist_head kprobe_insn_pages; | 120 | static LIST_HEAD(kprobe_insn_pages); |
121 | static int kprobe_garbage_slots; | 121 | static int kprobe_garbage_slots; |
122 | static int collect_garbage_slots(void); | 122 | static int collect_garbage_slots(void); |
123 | 123 | ||
@@ -152,10 +152,9 @@ loop_end: | |||
152 | static kprobe_opcode_t __kprobes *__get_insn_slot(void) | 152 | static kprobe_opcode_t __kprobes *__get_insn_slot(void) |
153 | { | 153 | { |
154 | struct kprobe_insn_page *kip; | 154 | struct kprobe_insn_page *kip; |
155 | struct hlist_node *pos; | ||
156 | 155 | ||
157 | retry: | 156 | retry: |
158 | hlist_for_each_entry(kip, pos, &kprobe_insn_pages, hlist) { | 157 | list_for_each_entry(kip, &kprobe_insn_pages, list) { |
159 | if (kip->nused < INSNS_PER_PAGE) { | 158 | if (kip->nused < INSNS_PER_PAGE) { |
160 | int i; | 159 | int i; |
161 | for (i = 0; i < INSNS_PER_PAGE; i++) { | 160 | for (i = 0; i < INSNS_PER_PAGE; i++) { |
@@ -189,8 +188,8 @@ static kprobe_opcode_t __kprobes *__get_insn_slot(void) | |||
189 | kfree(kip); | 188 | kfree(kip); |
190 | return NULL; | 189 | return NULL; |
191 | } | 190 | } |
192 | INIT_HLIST_NODE(&kip->hlist); | 191 | INIT_LIST_HEAD(&kip->list); |
193 | hlist_add_head(&kip->hlist, &kprobe_insn_pages); | 192 | list_add(&kip->list, &kprobe_insn_pages); |
194 | memset(kip->slot_used, SLOT_CLEAN, INSNS_PER_PAGE); | 193 | memset(kip->slot_used, SLOT_CLEAN, INSNS_PER_PAGE); |
195 | kip->slot_used[0] = SLOT_USED; | 194 | kip->slot_used[0] = SLOT_USED; |
196 | kip->nused = 1; | 195 | kip->nused = 1; |
@@ -219,12 +218,8 @@ static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx) | |||
219 | * so as not to have to set it up again the | 218 | * so as not to have to set it up again the |
220 | * next time somebody inserts a probe. | 219 | * next time somebody inserts a probe. |
221 | */ | 220 | */ |
222 | hlist_del(&kip->hlist); | 221 | if (!list_is_singular(&kprobe_insn_pages)) { |
223 | if (hlist_empty(&kprobe_insn_pages)) { | 222 | list_del(&kip->list); |
224 | INIT_HLIST_NODE(&kip->hlist); | ||
225 | hlist_add_head(&kip->hlist, | ||
226 | &kprobe_insn_pages); | ||
227 | } else { | ||
228 | module_free(NULL, kip->insns); | 223 | module_free(NULL, kip->insns); |
229 | kfree(kip); | 224 | kfree(kip); |
230 | } | 225 | } |
@@ -235,14 +230,13 @@ static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx) | |||
235 | 230 | ||
236 | static int __kprobes collect_garbage_slots(void) | 231 | static int __kprobes collect_garbage_slots(void) |
237 | { | 232 | { |
238 | struct kprobe_insn_page *kip; | 233 | struct kprobe_insn_page *kip, *next; |
239 | struct hlist_node *pos, *next; | ||
240 | 234 | ||
241 | /* Ensure no-one is preepmted on the garbages */ | 235 | /* Ensure no-one is preepmted on the garbages */ |
242 | if (check_safety()) | 236 | if (check_safety()) |
243 | return -EAGAIN; | 237 | return -EAGAIN; |
244 | 238 | ||
245 | hlist_for_each_entry_safe(kip, pos, next, &kprobe_insn_pages, hlist) { | 239 | list_for_each_entry_safe(kip, next, &kprobe_insn_pages, list) { |
246 | int i; | 240 | int i; |
247 | if (kip->ngarbage == 0) | 241 | if (kip->ngarbage == 0) |
248 | continue; | 242 | continue; |
@@ -260,19 +254,17 @@ static int __kprobes collect_garbage_slots(void) | |||
260 | void __kprobes free_insn_slot(kprobe_opcode_t * slot, int dirty) | 254 | void __kprobes free_insn_slot(kprobe_opcode_t * slot, int dirty) |
261 | { | 255 | { |
262 | struct kprobe_insn_page *kip; | 256 | struct kprobe_insn_page *kip; |
263 | struct hlist_node *pos; | ||
264 | 257 | ||
265 | mutex_lock(&kprobe_insn_mutex); | 258 | mutex_lock(&kprobe_insn_mutex); |
266 | hlist_for_each_entry(kip, pos, &kprobe_insn_pages, hlist) { | 259 | list_for_each_entry(kip, &kprobe_insn_pages, list) { |
267 | if (kip->insns <= slot && | 260 | if (kip->insns <= slot && |
268 | slot < kip->insns + (INSNS_PER_PAGE * MAX_INSN_SIZE)) { | 261 | slot < kip->insns + (INSNS_PER_PAGE * MAX_INSN_SIZE)) { |
269 | int i = (slot - kip->insns) / MAX_INSN_SIZE; | 262 | int i = (slot - kip->insns) / MAX_INSN_SIZE; |
270 | if (dirty) { | 263 | if (dirty) { |
271 | kip->slot_used[i] = SLOT_DIRTY; | 264 | kip->slot_used[i] = SLOT_DIRTY; |
272 | kip->ngarbage++; | 265 | kip->ngarbage++; |
273 | } else { | 266 | } else |
274 | collect_one_slot(kip, i); | 267 | collect_one_slot(kip, i); |
275 | } | ||
276 | break; | 268 | break; |
277 | } | 269 | } |
278 | } | 270 | } |