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-rw-r--r--arch/x86/include/asm/ds.h124
-rw-r--r--arch/x86/kernel/ds.c679
-rw-r--r--arch/x86/kernel/ptrace.c73
-rw-r--r--include/linux/sched.h9
4 files changed, 446 insertions, 439 deletions
diff --git a/arch/x86/include/asm/ds.h b/arch/x86/include/asm/ds.h
index a95008457ea4..0af997de5f01 100644
--- a/arch/x86/include/asm/ds.h
+++ b/arch/x86/include/asm/ds.h
@@ -26,11 +26,18 @@
26 26
27#include <linux/types.h> 27#include <linux/types.h>
28#include <linux/init.h> 28#include <linux/init.h>
29#include <linux/err.h>
29 30
30 31
31#ifdef CONFIG_X86_DS 32#ifdef CONFIG_X86_DS
32 33
33struct task_struct; 34struct task_struct;
35struct ds_tracer;
36struct bts_tracer;
37struct pebs_tracer;
38
39typedef void (*bts_ovfl_callback_t)(struct bts_tracer *);
40typedef void (*pebs_ovfl_callback_t)(struct pebs_tracer *);
34 41
35/* 42/*
36 * Request BTS or PEBS 43 * Request BTS or PEBS
@@ -38,21 +45,29 @@ struct task_struct;
38 * Due to alignement constraints, the actual buffer may be slightly 45 * Due to alignement constraints, the actual buffer may be slightly
39 * smaller than the requested or provided buffer. 46 * smaller than the requested or provided buffer.
40 * 47 *
41 * Returns 0 on success; -Eerrno otherwise 48 * Returns a pointer to a tracer structure on success, or
49 * ERR_PTR(errcode) on failure.
50 *
51 * The interrupt threshold is independent from the overflow callback
52 * to allow users to use their own overflow interrupt handling mechanism.
42 * 53 *
43 * task: the task to request recording for; 54 * task: the task to request recording for;
44 * NULL for per-cpu recording on the current cpu 55 * NULL for per-cpu recording on the current cpu
45 * base: the base pointer for the (non-pageable) buffer; 56 * base: the base pointer for the (non-pageable) buffer;
46 * NULL if buffer allocation requested 57 * NULL if buffer allocation requested
47 * size: the size of the requested or provided buffer 58 * size: the size of the requested or provided buffer in bytes
48 * ovfl: pointer to a function to be called on buffer overflow; 59 * ovfl: pointer to a function to be called on buffer overflow;
49 * NULL if cyclic buffer requested 60 * NULL if cyclic buffer requested
61 * th: the interrupt threshold in records from the end of the buffer;
62 * -1 if no interrupt threshold is requested.
50 */ 63 */
51typedef void (*ds_ovfl_callback_t)(struct task_struct *); 64extern struct bts_tracer *ds_request_bts(struct task_struct *task,
52extern int ds_request_bts(struct task_struct *task, void *base, size_t size, 65 void *base, size_t size,
53 ds_ovfl_callback_t ovfl); 66 bts_ovfl_callback_t ovfl, size_t th);
54extern int ds_request_pebs(struct task_struct *task, void *base, size_t size, 67extern struct pebs_tracer *ds_request_pebs(struct task_struct *task,
55 ds_ovfl_callback_t ovfl); 68 void *base, size_t size,
69 pebs_ovfl_callback_t ovfl,
70 size_t th);
56 71
57/* 72/*
58 * Release BTS or PEBS resources 73 * Release BTS or PEBS resources
@@ -61,37 +76,34 @@ extern int ds_request_pebs(struct task_struct *task, void *base, size_t size,
61 * 76 *
62 * Returns 0 on success; -Eerrno otherwise 77 * Returns 0 on success; -Eerrno otherwise
63 * 78 *
64 * task: the task to release resources for; 79 * tracer: the tracer handle returned from ds_request_~()
65 * NULL to release resources for the current cpu
66 */ 80 */
67extern int ds_release_bts(struct task_struct *task); 81extern int ds_release_bts(struct bts_tracer *tracer);
68extern int ds_release_pebs(struct task_struct *task); 82extern int ds_release_pebs(struct pebs_tracer *tracer);
69 83
70/* 84/*
71 * Return the (array) index of the write pointer. 85 * Get the (array) index of the write pointer.
72 * (assuming an array of BTS/PEBS records) 86 * (assuming an array of BTS/PEBS records)
73 * 87 *
74 * Returns -Eerrno on error 88 * Returns 0 on success; -Eerrno on error
75 * 89 *
76 * task: the task to access; 90 * tracer: the tracer handle returned from ds_request_~()
77 * NULL to access the current cpu 91 * pos (out): will hold the result
78 * pos (out): if not NULL, will hold the result
79 */ 92 */
80extern int ds_get_bts_index(struct task_struct *task, size_t *pos); 93extern int ds_get_bts_index(struct bts_tracer *tracer, size_t *pos);
81extern int ds_get_pebs_index(struct task_struct *task, size_t *pos); 94extern int ds_get_pebs_index(struct pebs_tracer *tracer, size_t *pos);
82 95
83/* 96/*
84 * Return the (array) index one record beyond the end of the array. 97 * Get the (array) index one record beyond the end of the array.
85 * (assuming an array of BTS/PEBS records) 98 * (assuming an array of BTS/PEBS records)
86 * 99 *
87 * Returns -Eerrno on error 100 * Returns 0 on success; -Eerrno on error
88 * 101 *
89 * task: the task to access; 102 * tracer: the tracer handle returned from ds_request_~()
90 * NULL to access the current cpu 103 * pos (out): will hold the result
91 * pos (out): if not NULL, will hold the result
92 */ 104 */
93extern int ds_get_bts_end(struct task_struct *task, size_t *pos); 105extern int ds_get_bts_end(struct bts_tracer *tracer, size_t *pos);
94extern int ds_get_pebs_end(struct task_struct *task, size_t *pos); 106extern int ds_get_pebs_end(struct pebs_tracer *tracer, size_t *pos);
95 107
96/* 108/*
97 * Provide a pointer to the BTS/PEBS record at parameter index. 109 * Provide a pointer to the BTS/PEBS record at parameter index.
@@ -102,14 +114,13 @@ extern int ds_get_pebs_end(struct task_struct *task, size_t *pos);
102 * 114 *
103 * Returns the size of a single record on success; -Eerrno on error 115 * Returns the size of a single record on success; -Eerrno on error
104 * 116 *
105 * task: the task to access; 117 * tracer: the tracer handle returned from ds_request_~()
106 * NULL to access the current cpu
107 * index: the index of the requested record 118 * index: the index of the requested record
108 * record (out): pointer to the requested record 119 * record (out): pointer to the requested record
109 */ 120 */
110extern int ds_access_bts(struct task_struct *task, 121extern int ds_access_bts(struct bts_tracer *tracer,
111 size_t index, const void **record); 122 size_t index, const void **record);
112extern int ds_access_pebs(struct task_struct *task, 123extern int ds_access_pebs(struct pebs_tracer *tracer,
113 size_t index, const void **record); 124 size_t index, const void **record);
114 125
115/* 126/*
@@ -129,38 +140,24 @@ extern int ds_access_pebs(struct task_struct *task,
129 * 140 *
130 * Returns the number of bytes written or -Eerrno. 141 * Returns the number of bytes written or -Eerrno.
131 * 142 *
132 * task: the task to access; 143 * tracer: the tracer handle returned from ds_request_~()
133 * NULL to access the current cpu
134 * buffer: the buffer to write 144 * buffer: the buffer to write
135 * size: the size of the buffer 145 * size: the size of the buffer
136 */ 146 */
137extern int ds_write_bts(struct task_struct *task, 147extern int ds_write_bts(struct bts_tracer *tracer,
138 const void *buffer, size_t size); 148 const void *buffer, size_t size);
139extern int ds_write_pebs(struct task_struct *task, 149extern int ds_write_pebs(struct pebs_tracer *tracer,
140 const void *buffer, size_t size); 150 const void *buffer, size_t size);
141 151
142/* 152/*
143 * Same as ds_write_bts/pebs, but omit ownership checks.
144 *
145 * This is needed to have some other task than the owner of the
146 * BTS/PEBS buffer or the parameter task itself write into the
147 * respective buffer.
148 */
149extern int ds_unchecked_write_bts(struct task_struct *task,
150 const void *buffer, size_t size);
151extern int ds_unchecked_write_pebs(struct task_struct *task,
152 const void *buffer, size_t size);
153
154/*
155 * Reset the write pointer of the BTS/PEBS buffer. 153 * Reset the write pointer of the BTS/PEBS buffer.
156 * 154 *
157 * Returns 0 on success; -Eerrno on error 155 * Returns 0 on success; -Eerrno on error
158 * 156 *
159 * task: the task to access; 157 * tracer: the tracer handle returned from ds_request_~()
160 * NULL to access the current cpu
161 */ 158 */
162extern int ds_reset_bts(struct task_struct *task); 159extern int ds_reset_bts(struct bts_tracer *tracer);
163extern int ds_reset_pebs(struct task_struct *task); 160extern int ds_reset_pebs(struct pebs_tracer *tracer);
164 161
165/* 162/*
166 * Clear the BTS/PEBS buffer and reset the write pointer. 163 * Clear the BTS/PEBS buffer and reset the write pointer.
@@ -168,33 +165,30 @@ extern int ds_reset_pebs(struct task_struct *task);
168 * 165 *
169 * Returns 0 on success; -Eerrno on error 166 * Returns 0 on success; -Eerrno on error
170 * 167 *
171 * task: the task to access; 168 * tracer: the tracer handle returned from ds_request_~()
172 * NULL to access the current cpu
173 */ 169 */
174extern int ds_clear_bts(struct task_struct *task); 170extern int ds_clear_bts(struct bts_tracer *tracer);
175extern int ds_clear_pebs(struct task_struct *task); 171extern int ds_clear_pebs(struct pebs_tracer *tracer);
176 172
177/* 173/*
178 * Provide the PEBS counter reset value. 174 * Provide the PEBS counter reset value.
179 * 175 *
180 * Returns 0 on success; -Eerrno on error 176 * Returns 0 on success; -Eerrno on error
181 * 177 *
182 * task: the task to access; 178 * tracer: the tracer handle returned from ds_request_pebs()
183 * NULL to access the current cpu
184 * value (out): the counter reset value 179 * value (out): the counter reset value
185 */ 180 */
186extern int ds_get_pebs_reset(struct task_struct *task, u64 *value); 181extern int ds_get_pebs_reset(struct pebs_tracer *tracer, u64 *value);
187 182
188/* 183/*
189 * Set the PEBS counter reset value. 184 * Set the PEBS counter reset value.
190 * 185 *
191 * Returns 0 on success; -Eerrno on error 186 * Returns 0 on success; -Eerrno on error
192 * 187 *
193 * task: the task to access; 188 * tracer: the tracer handle returned from ds_request_pebs()
194 * NULL to access the current cpu
195 * value: the new counter reset value 189 * value: the new counter reset value
196 */ 190 */
197extern int ds_set_pebs_reset(struct task_struct *task, u64 value); 191extern int ds_set_pebs_reset(struct pebs_tracer *tracer, u64 value);
198 192
199/* 193/*
200 * Initialization 194 * Initialization
@@ -207,17 +201,13 @@ extern void __cpuinit ds_init_intel(struct cpuinfo_x86 *);
207/* 201/*
208 * The DS context - part of struct thread_struct. 202 * The DS context - part of struct thread_struct.
209 */ 203 */
204#define MAX_SIZEOF_DS (12 * 8)
205
210struct ds_context { 206struct ds_context {
211 /* pointer to the DS configuration; goes into MSR_IA32_DS_AREA */ 207 /* pointer to the DS configuration; goes into MSR_IA32_DS_AREA */
212 unsigned char *ds; 208 unsigned char ds[MAX_SIZEOF_DS];
213 /* the owner of the BTS and PEBS configuration, respectively */ 209 /* the owner of the BTS and PEBS configuration, respectively */
214 struct task_struct *owner[2]; 210 struct ds_tracer *owner[2];
215 /* buffer overflow notification function for BTS and PEBS */
216 ds_ovfl_callback_t callback[2];
217 /* the original buffer address */
218 void *buffer[2];
219 /* the number of allocated pages for on-request allocated buffers */
220 unsigned int pages[2];
221 /* use count */ 211 /* use count */
222 unsigned long count; 212 unsigned long count;
223 /* a pointer to the context location inside the thread_struct 213 /* a pointer to the context location inside the thread_struct
diff --git a/arch/x86/kernel/ds.c b/arch/x86/kernel/ds.c
index d6938d9351cf..96768e9cce99 100644
--- a/arch/x86/kernel/ds.c
+++ b/arch/x86/kernel/ds.c
@@ -28,6 +28,7 @@
28#include <linux/slab.h> 28#include <linux/slab.h>
29#include <linux/sched.h> 29#include <linux/sched.h>
30#include <linux/mm.h> 30#include <linux/mm.h>
31#include <linux/kernel.h>
31 32
32 33
33/* 34/*
@@ -44,6 +45,35 @@ struct ds_configuration {
44}; 45};
45static struct ds_configuration ds_cfg; 46static struct ds_configuration ds_cfg;
46 47
48/*
49 * A BTS or PEBS tracer.
50 *
51 * This holds the configuration of the tracer and serves as a handle
52 * to identify tracers.
53 */
54struct ds_tracer {
55 /* the DS context (partially) owned by this tracer */
56 struct ds_context *context;
57 /* the buffer provided on ds_request() and its size in bytes */
58 void *buffer;
59 size_t size;
60 /* the number of allocated pages for on-request allocated buffers */
61 unsigned int pages;
62};
63
64struct bts_tracer {
65 /* the common DS part */
66 struct ds_tracer ds;
67 /* buffer overflow notification function */
68 bts_ovfl_callback_t ovfl;
69};
70
71struct pebs_tracer {
72 /* the common DS part */
73 struct ds_tracer ds;
74 /* buffer overflow notification function */
75 pebs_ovfl_callback_t ovfl;
76};
47 77
48/* 78/*
49 * Debug Store (DS) save area configuration (see Intel64 and IA32 79 * Debug Store (DS) save area configuration (see Intel64 and IA32
@@ -107,35 +137,15 @@ static inline void ds_set(unsigned char *base, enum ds_qualifier qual,
107 (*(unsigned long *)base) = value; 137 (*(unsigned long *)base) = value;
108} 138}
109 139
140#define DS_ALIGNMENT (1 << 3) /* BTS and PEBS buffer alignment */
141
110 142
111/* 143/*
112 * Locking is done only for allocating BTS or PEBS resources and for 144 * Locking is done only for allocating BTS or PEBS resources and for
113 * guarding context and buffer memory allocation. 145 * guarding context and buffer memory allocation.
114 *
115 * Most functions require the current task to own the ds context part
116 * they are going to access. All the locking is done when validating
117 * access to the context.
118 */ 146 */
119static spinlock_t ds_lock = __SPIN_LOCK_UNLOCKED(ds_lock); 147static spinlock_t ds_lock = __SPIN_LOCK_UNLOCKED(ds_lock);
120 148
121/*
122 * Validate that the current task is allowed to access the BTS/PEBS
123 * buffer of the parameter task.
124 *
125 * Returns 0, if access is granted; -Eerrno, otherwise.
126 */
127static inline int ds_validate_access(struct ds_context *context,
128 enum ds_qualifier qual)
129{
130 if (!context)
131 return -EPERM;
132
133 if (context->owner[qual] == current)
134 return 0;
135
136 return -EPERM;
137}
138
139 149
140/* 150/*
141 * We either support (system-wide) per-cpu or per-thread allocation. 151 * We either support (system-wide) per-cpu or per-thread allocation.
@@ -183,51 +193,13 @@ static inline int check_tracer(struct task_struct *task)
183 * 193 *
184 * Contexts are use-counted. They are allocated on first access and 194 * Contexts are use-counted. They are allocated on first access and
185 * deallocated when the last user puts the context. 195 * deallocated when the last user puts the context.
186 *
187 * We distinguish between an allocating and a non-allocating get of a
188 * context:
189 * - the allocating get is used for requesting BTS/PEBS resources. It
190 * requires the caller to hold the global ds_lock.
191 * - the non-allocating get is used for all other cases. A
192 * non-existing context indicates an error. It acquires and releases
193 * the ds_lock itself for obtaining the context.
194 *
195 * A context and its DS configuration are allocated and deallocated
196 * together. A context always has a DS configuration of the
197 * appropriate size.
198 */ 196 */
199static DEFINE_PER_CPU(struct ds_context *, system_context); 197static DEFINE_PER_CPU(struct ds_context *, system_context);
200 198
201#define this_system_context per_cpu(system_context, smp_processor_id()) 199#define this_system_context per_cpu(system_context, smp_processor_id())
202 200
203/*
204 * Returns the pointer to the parameter task's context or to the
205 * system-wide context, if task is NULL.
206 *
207 * Increases the use count of the returned context, if not NULL.
208 */
209static inline struct ds_context *ds_get_context(struct task_struct *task) 201static inline struct ds_context *ds_get_context(struct task_struct *task)
210{ 202{
211 struct ds_context *context;
212 unsigned long irq;
213
214 spin_lock_irqsave(&ds_lock, irq);
215
216 context = (task ? task->thread.ds_ctx : this_system_context);
217 if (context)
218 context->count++;
219
220 spin_unlock_irqrestore(&ds_lock, irq);
221
222 return context;
223}
224
225/*
226 * Same as ds_get_context, but allocates the context and it's DS
227 * structure, if necessary; returns NULL; if out of memory.
228 */
229static inline struct ds_context *ds_alloc_context(struct task_struct *task)
230{
231 struct ds_context **p_context = 203 struct ds_context **p_context =
232 (task ? &task->thread.ds_ctx : &this_system_context); 204 (task ? &task->thread.ds_ctx : &this_system_context);
233 struct ds_context *context = *p_context; 205 struct ds_context *context = *p_context;
@@ -238,16 +210,9 @@ static inline struct ds_context *ds_alloc_context(struct task_struct *task)
238 if (!context) 210 if (!context)
239 return NULL; 211 return NULL;
240 212
241 context->ds = kzalloc(ds_cfg.sizeof_ds, GFP_KERNEL);
242 if (!context->ds) {
243 kfree(context);
244 return NULL;
245 }
246
247 spin_lock_irqsave(&ds_lock, irq); 213 spin_lock_irqsave(&ds_lock, irq);
248 214
249 if (*p_context) { 215 if (*p_context) {
250 kfree(context->ds);
251 kfree(context); 216 kfree(context);
252 217
253 context = *p_context; 218 context = *p_context;
@@ -272,10 +237,6 @@ static inline struct ds_context *ds_alloc_context(struct task_struct *task)
272 return context; 237 return context;
273} 238}
274 239
275/*
276 * Decreases the use count of the parameter context, if not NULL.
277 * Deallocates the context, if the use count reaches zero.
278 */
279static inline void ds_put_context(struct ds_context *context) 240static inline void ds_put_context(struct ds_context *context)
280{ 241{
281 unsigned long irq; 242 unsigned long irq;
@@ -296,13 +257,6 @@ static inline void ds_put_context(struct ds_context *context)
296 if (!context->task || (context->task == current)) 257 if (!context->task || (context->task == current))
297 wrmsrl(MSR_IA32_DS_AREA, 0); 258 wrmsrl(MSR_IA32_DS_AREA, 0);
298 259
299 put_tracer(context->task);
300
301 /* free any leftover buffers from tracers that did not
302 * deallocate them properly. */
303 kfree(context->buffer[ds_bts]);
304 kfree(context->buffer[ds_pebs]);
305 kfree(context->ds);
306 kfree(context); 260 kfree(context);
307 out: 261 out:
308 spin_unlock_irqrestore(&ds_lock, irq); 262 spin_unlock_irqrestore(&ds_lock, irq);
@@ -312,21 +266,29 @@ static inline void ds_put_context(struct ds_context *context)
312/* 266/*
313 * Handle a buffer overflow 267 * Handle a buffer overflow
314 * 268 *
315 * task: the task whose buffers are overflowing;
316 * NULL for a buffer overflow on the current cpu
317 * context: the ds context 269 * context: the ds context
318 * qual: the buffer type 270 * qual: the buffer type
319 */ 271 */
320static void ds_overflow(struct task_struct *task, struct ds_context *context, 272static void ds_overflow(struct ds_context *context, enum ds_qualifier qual)
321 enum ds_qualifier qual) 273{
322{ 274 switch (qual) {
323 if (!context) 275 case ds_bts: {
324 return; 276 struct bts_tracer *tracer =
325 277 container_of(context->owner[qual],
326 if (context->callback[qual]) 278 struct bts_tracer, ds);
327 (*context->callback[qual])(task); 279 if (tracer->ovfl)
328 280 tracer->ovfl(tracer);
329 /* todo: do some more overflow handling */ 281 }
282 break;
283 case ds_pebs: {
284 struct pebs_tracer *tracer =
285 container_of(context->owner[qual],
286 struct pebs_tracer, ds);
287 if (tracer->ovfl)
288 tracer->ovfl(tracer);
289 }
290 break;
291 }
330} 292}
331 293
332 294
@@ -343,23 +305,25 @@ static void ds_overflow(struct task_struct *task, struct ds_context *context,
343static inline void *ds_allocate_buffer(size_t size, unsigned int *pages) 305static inline void *ds_allocate_buffer(size_t size, unsigned int *pages)
344{ 306{
345 unsigned long rlim, vm, pgsz; 307 unsigned long rlim, vm, pgsz;
346 void *buffer; 308 void *buffer = NULL;
347 309
348 pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT; 310 pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT;
349 311
312 down_write(&current->mm->mmap_sem);
313
350 rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT; 314 rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
351 vm = current->mm->total_vm + pgsz; 315 vm = current->mm->total_vm + pgsz;
352 if (rlim < vm) 316 if (rlim < vm)
353 return NULL; 317 goto out;
354 318
355 rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT; 319 rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
356 vm = current->mm->locked_vm + pgsz; 320 vm = current->mm->locked_vm + pgsz;
357 if (rlim < vm) 321 if (rlim < vm)
358 return NULL; 322 goto out;
359 323
360 buffer = kzalloc(size, GFP_KERNEL); 324 buffer = kzalloc(size, GFP_KERNEL);
361 if (!buffer) 325 if (!buffer)
362 return NULL; 326 goto out;
363 327
364 current->mm->total_vm += pgsz; 328 current->mm->total_vm += pgsz;
365 current->mm->locked_vm += pgsz; 329 current->mm->locked_vm += pgsz;
@@ -367,290 +331,337 @@ static inline void *ds_allocate_buffer(size_t size, unsigned int *pages)
367 if (pages) 331 if (pages)
368 *pages = pgsz; 332 *pages = pgsz;
369 333
334 out:
335 up_write(&current->mm->mmap_sem);
370 return buffer; 336 return buffer;
371} 337}
372 338
373static int ds_request(struct task_struct *task, void *base, size_t size, 339static void ds_install_ds_config(struct ds_context *context,
374 ds_ovfl_callback_t ovfl, enum ds_qualifier qual) 340 enum ds_qualifier qual,
341 void *base, size_t size, size_t ith)
375{ 342{
376 struct ds_context *context;
377 unsigned long buffer, adj; 343 unsigned long buffer, adj;
378 const unsigned long alignment = (1 << 3); 344
345 /* adjust the buffer address and size to meet alignment
346 * constraints:
347 * - buffer is double-word aligned
348 * - size is multiple of record size
349 *
350 * We checked the size at the very beginning; we have enough
351 * space to do the adjustment.
352 */
353 buffer = (unsigned long)base;
354
355 adj = ALIGN(buffer, DS_ALIGNMENT) - buffer;
356 buffer += adj;
357 size -= adj;
358
359 size /= ds_cfg.sizeof_rec[qual];
360 size *= ds_cfg.sizeof_rec[qual];
361
362 ds_set(context->ds, qual, ds_buffer_base, buffer);
363 ds_set(context->ds, qual, ds_index, buffer);
364 ds_set(context->ds, qual, ds_absolute_maximum, buffer + size);
365
366 /* The value for 'no threshold' is -1, which will set the
367 * threshold outside of the buffer, just like we want it.
368 */
369 ds_set(context->ds, qual,
370 ds_interrupt_threshold, buffer + size - ith);
371}
372
373static int ds_request(struct ds_tracer *tracer, enum ds_qualifier qual,
374 struct task_struct *task,
375 void *base, size_t size, size_t th)
376{
377 struct ds_context *context;
379 unsigned long irq; 378 unsigned long irq;
380 int error = 0; 379 int error;
381 380
381 error = -EOPNOTSUPP;
382 if (!ds_cfg.sizeof_ds) 382 if (!ds_cfg.sizeof_ds)
383 return -EOPNOTSUPP; 383 goto out;
384 384
385 /* we require some space to do alignment adjustments below */ 385 /* we require some space to do alignment adjustments below */
386 if (size < (alignment + ds_cfg.sizeof_rec[qual])) 386 error = -EINVAL;
387 return -EINVAL; 387 if (size < (DS_ALIGNMENT + ds_cfg.sizeof_rec[qual]))
388 goto out;
388 389
389 /* buffer overflow notification is not yet implemented */ 390 if (th != (size_t)-1) {
390 if (ovfl) 391 th *= ds_cfg.sizeof_rec[qual];
391 return -EOPNOTSUPP; 392
393 error = -EINVAL;
394 if (size <= th)
395 goto out;
396 }
397
398 error = -ENOMEM;
399 if (!base) {
400 base = ds_allocate_buffer(size, &tracer->pages);
401 if (!base)
402 goto out;
403 }
392 404
405 tracer->buffer = base;
406 tracer->size = size;
393 407
394 context = ds_alloc_context(task); 408 error = -ENOMEM;
409 context = ds_get_context(task);
395 if (!context) 410 if (!context)
396 return -ENOMEM; 411 goto out;
412 tracer->context = context;
413
397 414
398 spin_lock_irqsave(&ds_lock, irq); 415 spin_lock_irqsave(&ds_lock, irq);
399 416
400 error = -EPERM; 417 error = -EPERM;
401 if (!check_tracer(task)) 418 if (!check_tracer(task))
402 goto out_unlock; 419 goto out_unlock;
403
404 get_tracer(task); 420 get_tracer(task);
405 421
406 error = -EALREADY;
407 if (context->owner[qual] == current)
408 goto out_put_tracer;
409 error = -EPERM; 422 error = -EPERM;
410 if (context->owner[qual] != NULL) 423 if (context->owner[qual])
411 goto out_put_tracer; 424 goto out_put_tracer;
412 context->owner[qual] = current; 425 context->owner[qual] = tracer;
413 426
414 spin_unlock_irqrestore(&ds_lock, irq); 427 spin_unlock_irqrestore(&ds_lock, irq);
415 428
416 429
417 error = -ENOMEM; 430 ds_install_ds_config(context, qual, base, size, th);
418 if (!base) {
419 base = ds_allocate_buffer(size, &context->pages[qual]);
420 if (!base)
421 goto out_release;
422
423 context->buffer[qual] = base;
424 }
425 error = 0;
426 431
427 context->callback[qual] = ovfl; 432 return 0;
428
429 /* adjust the buffer address and size to meet alignment
430 * constraints:
431 * - buffer is double-word aligned
432 * - size is multiple of record size
433 *
434 * We checked the size at the very beginning; we have enough
435 * space to do the adjustment.
436 */
437 buffer = (unsigned long)base;
438
439 adj = ALIGN(buffer, alignment) - buffer;
440 buffer += adj;
441 size -= adj;
442
443 size /= ds_cfg.sizeof_rec[qual];
444 size *= ds_cfg.sizeof_rec[qual];
445
446 ds_set(context->ds, qual, ds_buffer_base, buffer);
447 ds_set(context->ds, qual, ds_index, buffer);
448 ds_set(context->ds, qual, ds_absolute_maximum, buffer + size);
449
450 if (ovfl) {
451 /* todo: select a suitable interrupt threshold */
452 } else
453 ds_set(context->ds, qual,
454 ds_interrupt_threshold, buffer + size + 1);
455
456 /* we keep the context until ds_release */
457 return error;
458
459 out_release:
460 context->owner[qual] = NULL;
461 ds_put_context(context);
462 put_tracer(task);
463 return error;
464 433
465 out_put_tracer: 434 out_put_tracer:
466 spin_unlock_irqrestore(&ds_lock, irq);
467 ds_put_context(context);
468 put_tracer(task); 435 put_tracer(task);
469 return error;
470
471 out_unlock: 436 out_unlock:
472 spin_unlock_irqrestore(&ds_lock, irq); 437 spin_unlock_irqrestore(&ds_lock, irq);
473 ds_put_context(context); 438 ds_put_context(context);
439 tracer->context = NULL;
440 out:
474 return error; 441 return error;
475} 442}
476 443
477int ds_request_bts(struct task_struct *task, void *base, size_t size, 444struct bts_tracer *ds_request_bts(struct task_struct *task,
478 ds_ovfl_callback_t ovfl) 445 void *base, size_t size,
446 bts_ovfl_callback_t ovfl, size_t th)
479{ 447{
480 return ds_request(task, base, size, ovfl, ds_bts); 448 struct bts_tracer *tracer;
481} 449 int error;
482 450
483int ds_request_pebs(struct task_struct *task, void *base, size_t size, 451 /* buffer overflow notification is not yet implemented */
484 ds_ovfl_callback_t ovfl) 452 error = -EOPNOTSUPP;
485{ 453 if (ovfl)
486 return ds_request(task, base, size, ovfl, ds_pebs); 454 goto out;
455
456 error = -ENOMEM;
457 tracer = kzalloc(sizeof(*tracer), GFP_KERNEL);
458 if (!tracer)
459 goto out;
460 tracer->ovfl = ovfl;
461
462 error = ds_request(&tracer->ds, ds_bts, task, base, size, th);
463 if (error < 0)
464 goto out_tracer;
465
466 return tracer;
467
468 out_tracer:
469 (void)ds_release_bts(tracer);
470 out:
471 return ERR_PTR(error);
487} 472}
488 473
489static int ds_release(struct task_struct *task, enum ds_qualifier qual) 474struct pebs_tracer *ds_request_pebs(struct task_struct *task,
475 void *base, size_t size,
476 pebs_ovfl_callback_t ovfl, size_t th)
490{ 477{
491 struct ds_context *context; 478 struct pebs_tracer *tracer;
492 int error; 479 int error;
493 480
494 context = ds_get_context(task); 481 /* buffer overflow notification is not yet implemented */
495 error = ds_validate_access(context, qual); 482 error = -EOPNOTSUPP;
496 if (error < 0) 483 if (ovfl)
497 goto out; 484 goto out;
498 485
499 kfree(context->buffer[qual]); 486 error = -ENOMEM;
500 context->buffer[qual] = NULL; 487 tracer = kzalloc(sizeof(*tracer), GFP_KERNEL);
488 if (!tracer)
489 goto out;
490 tracer->ovfl = ovfl;
501 491
502 current->mm->total_vm -= context->pages[qual]; 492 error = ds_request(&tracer->ds, ds_pebs, task, base, size, th);
503 current->mm->locked_vm -= context->pages[qual]; 493 if (error < 0)
504 context->pages[qual] = 0; 494 goto out_tracer;
505 context->owner[qual] = NULL;
506 495
507 /* 496 return tracer;
508 * we put the context twice: 497
509 * once for the ds_get_context 498 out_tracer:
510 * once for the corresponding ds_request 499 (void)ds_release_pebs(tracer);
511 */
512 ds_put_context(context);
513 out: 500 out:
514 ds_put_context(context); 501 return ERR_PTR(error);
515 return error; 502}
503
504static void ds_release(struct ds_tracer *tracer, enum ds_qualifier qual)
505{
506 if (tracer->context) {
507 BUG_ON(tracer->context->owner[qual] != tracer);
508 tracer->context->owner[qual] = NULL;
509
510 put_tracer(tracer->context->task);
511 ds_put_context(tracer->context);
512 }
513
514 if (tracer->pages) {
515 kfree(tracer->buffer);
516
517 down_write(&current->mm->mmap_sem);
518
519 current->mm->total_vm -= tracer->pages;
520 current->mm->locked_vm -= tracer->pages;
521
522 up_write(&current->mm->mmap_sem);
523 }
516} 524}
517 525
518int ds_release_bts(struct task_struct *task) 526int ds_release_bts(struct bts_tracer *tracer)
519{ 527{
520 return ds_release(task, ds_bts); 528 if (!tracer)
529 return -EINVAL;
530
531 ds_release(&tracer->ds, ds_bts);
532 kfree(tracer);
533
534 return 0;
521} 535}
522 536
523int ds_release_pebs(struct task_struct *task) 537int ds_release_pebs(struct pebs_tracer *tracer)
524{ 538{
525 return ds_release(task, ds_pebs); 539 if (!tracer)
540 return -EINVAL;
541
542 ds_release(&tracer->ds, ds_pebs);
543 kfree(tracer);
544
545 return 0;
526} 546}
527 547
528static int ds_get_index(struct task_struct *task, size_t *pos, 548static size_t ds_get_index(struct ds_context *context, enum ds_qualifier qual)
529 enum ds_qualifier qual)
530{ 549{
531 struct ds_context *context;
532 unsigned long base, index; 550 unsigned long base, index;
533 int error;
534
535 context = ds_get_context(task);
536 error = ds_validate_access(context, qual);
537 if (error < 0)
538 goto out;
539 551
540 base = ds_get(context->ds, qual, ds_buffer_base); 552 base = ds_get(context->ds, qual, ds_buffer_base);
541 index = ds_get(context->ds, qual, ds_index); 553 index = ds_get(context->ds, qual, ds_index);
542 554
543 error = ((index - base) / ds_cfg.sizeof_rec[qual]); 555 return (index - base) / ds_cfg.sizeof_rec[qual];
544 if (pos)
545 *pos = error;
546 out:
547 ds_put_context(context);
548 return error;
549} 556}
550 557
551int ds_get_bts_index(struct task_struct *task, size_t *pos) 558int ds_get_bts_index(struct bts_tracer *tracer, size_t *pos)
552{ 559{
553 return ds_get_index(task, pos, ds_bts); 560 if (!tracer)
561 return -EINVAL;
562
563 if (!pos)
564 return -EINVAL;
565
566 *pos = ds_get_index(tracer->ds.context, ds_bts);
567
568 return 0;
554} 569}
555 570
556int ds_get_pebs_index(struct task_struct *task, size_t *pos) 571int ds_get_pebs_index(struct pebs_tracer *tracer, size_t *pos)
557{ 572{
558 return ds_get_index(task, pos, ds_pebs); 573 if (!tracer)
574 return -EINVAL;
575
576 if (!pos)
577 return -EINVAL;
578
579 *pos = ds_get_index(tracer->ds.context, ds_pebs);
580
581 return 0;
559} 582}
560 583
561static int ds_get_end(struct task_struct *task, size_t *pos, 584static size_t ds_get_end(struct ds_context *context, enum ds_qualifier qual)
562 enum ds_qualifier qual)
563{ 585{
564 struct ds_context *context; 586 unsigned long base, max;
565 unsigned long base, end;
566 int error;
567
568 context = ds_get_context(task);
569 error = ds_validate_access(context, qual);
570 if (error < 0)
571 goto out;
572 587
573 base = ds_get(context->ds, qual, ds_buffer_base); 588 base = ds_get(context->ds, qual, ds_buffer_base);
574 end = ds_get(context->ds, qual, ds_absolute_maximum); 589 max = ds_get(context->ds, qual, ds_absolute_maximum);
575 590
576 error = ((end - base) / ds_cfg.sizeof_rec[qual]); 591 return (max - base) / ds_cfg.sizeof_rec[qual];
577 if (pos)
578 *pos = error;
579 out:
580 ds_put_context(context);
581 return error;
582} 592}
583 593
584int ds_get_bts_end(struct task_struct *task, size_t *pos) 594int ds_get_bts_end(struct bts_tracer *tracer, size_t *pos)
585{ 595{
586 return ds_get_end(task, pos, ds_bts); 596 if (!tracer)
597 return -EINVAL;
598
599 if (!pos)
600 return -EINVAL;
601
602 *pos = ds_get_end(tracer->ds.context, ds_bts);
603
604 return 0;
587} 605}
588 606
589int ds_get_pebs_end(struct task_struct *task, size_t *pos) 607int ds_get_pebs_end(struct pebs_tracer *tracer, size_t *pos)
590{ 608{
591 return ds_get_end(task, pos, ds_pebs); 609 if (!tracer)
610 return -EINVAL;
611
612 if (!pos)
613 return -EINVAL;
614
615 *pos = ds_get_end(tracer->ds.context, ds_pebs);
616
617 return 0;
592} 618}
593 619
594static int ds_access(struct task_struct *task, size_t index, 620static int ds_access(struct ds_context *context, enum ds_qualifier qual,
595 const void **record, enum ds_qualifier qual) 621 size_t index, const void **record)
596{ 622{
597 struct ds_context *context;
598 unsigned long base, idx; 623 unsigned long base, idx;
599 int error;
600 624
601 if (!record) 625 if (!record)
602 return -EINVAL; 626 return -EINVAL;
603 627
604 context = ds_get_context(task);
605 error = ds_validate_access(context, qual);
606 if (error < 0)
607 goto out;
608
609 base = ds_get(context->ds, qual, ds_buffer_base); 628 base = ds_get(context->ds, qual, ds_buffer_base);
610 idx = base + (index * ds_cfg.sizeof_rec[qual]); 629 idx = base + (index * ds_cfg.sizeof_rec[qual]);
611 630
612 error = -EINVAL;
613 if (idx > ds_get(context->ds, qual, ds_absolute_maximum)) 631 if (idx > ds_get(context->ds, qual, ds_absolute_maximum))
614 goto out; 632 return -EINVAL;
615 633
616 *record = (const void *)idx; 634 *record = (const void *)idx;
617 error = ds_cfg.sizeof_rec[qual]; 635
618 out: 636 return ds_cfg.sizeof_rec[qual];
619 ds_put_context(context);
620 return error;
621} 637}
622 638
623int ds_access_bts(struct task_struct *task, size_t index, const void **record) 639int ds_access_bts(struct bts_tracer *tracer, size_t index,
640 const void **record)
624{ 641{
625 return ds_access(task, index, record, ds_bts); 642 if (!tracer)
643 return -EINVAL;
644
645 return ds_access(tracer->ds.context, ds_bts, index, record);
626} 646}
627 647
628int ds_access_pebs(struct task_struct *task, size_t index, const void **record) 648int ds_access_pebs(struct pebs_tracer *tracer, size_t index,
649 const void **record)
629{ 650{
630 return ds_access(task, index, record, ds_pebs); 651 if (!tracer)
652 return -EINVAL;
653
654 return ds_access(tracer->ds.context, ds_pebs, index, record);
631} 655}
632 656
633static int ds_write(struct task_struct *task, const void *record, size_t size, 657static int ds_write(struct ds_context *context, enum ds_qualifier qual,
634 enum ds_qualifier qual, int force) 658 const void *record, size_t size)
635{ 659{
636 struct ds_context *context; 660 int bytes_written = 0;
637 int error;
638 661
639 if (!record) 662 if (!record)
640 return -EINVAL; 663 return -EINVAL;
641 664
642 error = -EPERM;
643 context = ds_get_context(task);
644 if (!context)
645 goto out;
646
647 if (!force) {
648 error = ds_validate_access(context, qual);
649 if (error < 0)
650 goto out;
651 }
652
653 error = 0;
654 while (size) { 665 while (size) {
655 unsigned long base, index, end, write_end, int_th; 666 unsigned long base, index, end, write_end, int_th;
656 unsigned long write_size, adj_write_size; 667 unsigned long write_size, adj_write_size;
@@ -678,14 +689,14 @@ static int ds_write(struct task_struct *task, const void *record, size_t size,
678 write_end = end; 689 write_end = end;
679 690
680 if (write_end <= index) 691 if (write_end <= index)
681 goto out; 692 break;
682 693
683 write_size = min((unsigned long) size, write_end - index); 694 write_size = min((unsigned long) size, write_end - index);
684 memcpy((void *)index, record, write_size); 695 memcpy((void *)index, record, write_size);
685 696
686 record = (const char *)record + write_size; 697 record = (const char *)record + write_size;
687 size -= write_size; 698 size -= write_size;
688 error += write_size; 699 bytes_written += write_size;
689 700
690 adj_write_size = write_size / ds_cfg.sizeof_rec[qual]; 701 adj_write_size = write_size / ds_cfg.sizeof_rec[qual];
691 adj_write_size *= ds_cfg.sizeof_rec[qual]; 702 adj_write_size *= ds_cfg.sizeof_rec[qual];
@@ -700,47 +711,32 @@ static int ds_write(struct task_struct *task, const void *record, size_t size,
700 ds_set(context->ds, qual, ds_index, index); 711 ds_set(context->ds, qual, ds_index, index);
701 712
702 if (index >= int_th) 713 if (index >= int_th)
703 ds_overflow(task, context, qual); 714 ds_overflow(context, qual);
704 } 715 }
705 716
706 out: 717 return bytes_written;
707 ds_put_context(context);
708 return error;
709} 718}
710 719
711int ds_write_bts(struct task_struct *task, const void *record, size_t size) 720int ds_write_bts(struct bts_tracer *tracer, const void *record, size_t size)
712{ 721{
713 return ds_write(task, record, size, ds_bts, /* force = */ 0); 722 if (!tracer)
714} 723 return -EINVAL;
715 724
716int ds_write_pebs(struct task_struct *task, const void *record, size_t size) 725 return ds_write(tracer->ds.context, ds_bts, record, size);
717{
718 return ds_write(task, record, size, ds_pebs, /* force = */ 0);
719} 726}
720 727
721int ds_unchecked_write_bts(struct task_struct *task, 728int ds_write_pebs(struct pebs_tracer *tracer, const void *record, size_t size)
722 const void *record, size_t size)
723{ 729{
724 return ds_write(task, record, size, ds_bts, /* force = */ 1); 730 if (!tracer)
725} 731 return -EINVAL;
726 732
727int ds_unchecked_write_pebs(struct task_struct *task, 733 return ds_write(tracer->ds.context, ds_pebs, record, size);
728 const void *record, size_t size)
729{
730 return ds_write(task, record, size, ds_pebs, /* force = */ 1);
731} 734}
732 735
733static int ds_reset_or_clear(struct task_struct *task, 736static void ds_reset_or_clear(struct ds_context *context,
734 enum ds_qualifier qual, int clear) 737 enum ds_qualifier qual, int clear)
735{ 738{
736 struct ds_context *context;
737 unsigned long base, end; 739 unsigned long base, end;
738 int error;
739
740 context = ds_get_context(task);
741 error = ds_validate_access(context, qual);
742 if (error < 0)
743 goto out;
744 740
745 base = ds_get(context->ds, qual, ds_buffer_base); 741 base = ds_get(context->ds, qual, ds_buffer_base);
746 end = ds_get(context->ds, qual, ds_absolute_maximum); 742 end = ds_get(context->ds, qual, ds_absolute_maximum);
@@ -749,70 +745,69 @@ static int ds_reset_or_clear(struct task_struct *task,
749 memset((void *)base, 0, end - base); 745 memset((void *)base, 0, end - base);
750 746
751 ds_set(context->ds, qual, ds_index, base); 747 ds_set(context->ds, qual, ds_index, base);
752
753 error = 0;
754 out:
755 ds_put_context(context);
756 return error;
757} 748}
758 749
759int ds_reset_bts(struct task_struct *task) 750int ds_reset_bts(struct bts_tracer *tracer)
760{ 751{
761 return ds_reset_or_clear(task, ds_bts, /* clear = */ 0); 752 if (!tracer)
753 return -EINVAL;
754
755 ds_reset_or_clear(tracer->ds.context, ds_bts, /* clear = */ 0);
756
757 return 0;
762} 758}
763 759
764int ds_reset_pebs(struct task_struct *task) 760int ds_reset_pebs(struct pebs_tracer *tracer)
765{ 761{
766 return ds_reset_or_clear(task, ds_pebs, /* clear = */ 0); 762 if (!tracer)
763 return -EINVAL;
764
765 ds_reset_or_clear(tracer->ds.context, ds_pebs, /* clear = */ 0);
766
767 return 0;
767} 768}
768 769
769int ds_clear_bts(struct task_struct *task) 770int ds_clear_bts(struct bts_tracer *tracer)
770{ 771{
771 return ds_reset_or_clear(task, ds_bts, /* clear = */ 1); 772 if (!tracer)
773 return -EINVAL;
774
775 ds_reset_or_clear(tracer->ds.context, ds_bts, /* clear = */ 1);
776
777 return 0;
772} 778}
773 779
774int ds_clear_pebs(struct task_struct *task) 780int ds_clear_pebs(struct pebs_tracer *tracer)
775{ 781{
776 return ds_reset_or_clear(task, ds_pebs, /* clear = */ 1); 782 if (!tracer)
783 return -EINVAL;
784
785 ds_reset_or_clear(tracer->ds.context, ds_pebs, /* clear = */ 1);
786
787 return 0;
777} 788}
778 789
779int ds_get_pebs_reset(struct task_struct *task, u64 *value) 790int ds_get_pebs_reset(struct pebs_tracer *tracer, u64 *value)
780{ 791{
781 struct ds_context *context; 792 if (!tracer)
782 int error; 793 return -EINVAL;
783 794
784 if (!value) 795 if (!value)
785 return -EINVAL; 796 return -EINVAL;
786 797
787 context = ds_get_context(task); 798 *value = *(u64 *)(tracer->ds.context->ds + (ds_cfg.sizeof_field * 8));
788 error = ds_validate_access(context, ds_pebs);
789 if (error < 0)
790 goto out;
791
792 *value = *(u64 *)(context->ds + (ds_cfg.sizeof_field * 8));
793 799
794 error = 0; 800 return 0;
795 out:
796 ds_put_context(context);
797 return error;
798} 801}
799 802
800int ds_set_pebs_reset(struct task_struct *task, u64 value) 803int ds_set_pebs_reset(struct pebs_tracer *tracer, u64 value)
801{ 804{
802 struct ds_context *context; 805 if (!tracer)
803 int error; 806 return -EINVAL;
804
805 context = ds_get_context(task);
806 error = ds_validate_access(context, ds_pebs);
807 if (error < 0)
808 goto out;
809 807
810 *(u64 *)(context->ds + (ds_cfg.sizeof_field * 8)) = value; 808 *(u64 *)(tracer->ds.context->ds + (ds_cfg.sizeof_field * 8)) = value;
811 809
812 error = 0; 810 return 0;
813 out:
814 ds_put_context(context);
815 return error;
816} 811}
817 812
818static const struct ds_configuration ds_cfg_var = { 813static const struct ds_configuration ds_cfg_var = {
@@ -840,6 +835,10 @@ static inline void
840ds_configure(const struct ds_configuration *cfg) 835ds_configure(const struct ds_configuration *cfg)
841{ 836{
842 ds_cfg = *cfg; 837 ds_cfg = *cfg;
838
839 printk(KERN_INFO "DS available\n");
840
841 BUG_ON(MAX_SIZEOF_DS < ds_cfg.sizeof_ds);
843} 842}
844 843
845void __cpuinit ds_init_intel(struct cpuinfo_x86 *c) 844void __cpuinit ds_init_intel(struct cpuinfo_x86 *c)
@@ -883,6 +882,8 @@ void ds_free(struct ds_context *context)
883 * is dying. There should not be any user of that context left 882 * is dying. There should not be any user of that context left
884 * to disturb us, anymore. */ 883 * to disturb us, anymore. */
885 unsigned long leftovers = context->count; 884 unsigned long leftovers = context->count;
886 while (leftovers--) 885 while (leftovers--) {
886 put_tracer(context->task);
887 ds_put_context(context); 887 ds_put_context(context);
888 }
888} 889}
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 06180dff5b2e..76adf5b640ff 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -668,14 +668,14 @@ static int ptrace_bts_read_record(struct task_struct *child, size_t index,
668 size_t bts_index, bts_end; 668 size_t bts_index, bts_end;
669 int error; 669 int error;
670 670
671 error = ds_get_bts_end(child, &bts_end); 671 error = ds_get_bts_end(child->bts, &bts_end);
672 if (error < 0) 672 if (error < 0)
673 return error; 673 return error;
674 674
675 if (bts_end <= index) 675 if (bts_end <= index)
676 return -EINVAL; 676 return -EINVAL;
677 677
678 error = ds_get_bts_index(child, &bts_index); 678 error = ds_get_bts_index(child->bts, &bts_index);
679 if (error < 0) 679 if (error < 0)
680 return error; 680 return error;
681 681
@@ -684,7 +684,7 @@ static int ptrace_bts_read_record(struct task_struct *child, size_t index,
684 if (bts_end <= bts_index) 684 if (bts_end <= bts_index)
685 bts_index -= bts_end; 685 bts_index -= bts_end;
686 686
687 error = ds_access_bts(child, bts_index, &bts_record); 687 error = ds_access_bts(child->bts, bts_index, &bts_record);
688 if (error < 0) 688 if (error < 0)
689 return error; 689 return error;
690 690
@@ -705,14 +705,14 @@ static int ptrace_bts_drain(struct task_struct *child,
705 size_t end, i; 705 size_t end, i;
706 int error; 706 int error;
707 707
708 error = ds_get_bts_index(child, &end); 708 error = ds_get_bts_index(child->bts, &end);
709 if (error < 0) 709 if (error < 0)
710 return error; 710 return error;
711 711
712 if (size < (end * sizeof(struct bts_struct))) 712 if (size < (end * sizeof(struct bts_struct)))
713 return -EIO; 713 return -EIO;
714 714
715 error = ds_access_bts(child, 0, (const void **)&raw); 715 error = ds_access_bts(child->bts, 0, (const void **)&raw);
716 if (error < 0) 716 if (error < 0)
717 return error; 717 return error;
718 718
@@ -723,18 +723,13 @@ static int ptrace_bts_drain(struct task_struct *child,
723 return -EFAULT; 723 return -EFAULT;
724 } 724 }
725 725
726 error = ds_clear_bts(child); 726 error = ds_clear_bts(child->bts);
727 if (error < 0) 727 if (error < 0)
728 return error; 728 return error;
729 729
730 return end; 730 return end;
731} 731}
732 732
733static void ptrace_bts_ovfl(struct task_struct *child)
734{
735 send_sig(child->thread.bts_ovfl_signal, child, 0);
736}
737
738static int ptrace_bts_config(struct task_struct *child, 733static int ptrace_bts_config(struct task_struct *child,
739 long cfg_size, 734 long cfg_size,
740 const struct ptrace_bts_config __user *ucfg) 735 const struct ptrace_bts_config __user *ucfg)
@@ -760,23 +755,29 @@ static int ptrace_bts_config(struct task_struct *child,
760 goto errout; 755 goto errout;
761 756
762 if (cfg.flags & PTRACE_BTS_O_ALLOC) { 757 if (cfg.flags & PTRACE_BTS_O_ALLOC) {
763 ds_ovfl_callback_t ovfl = NULL; 758 bts_ovfl_callback_t ovfl = NULL;
764 unsigned int sig = 0; 759 unsigned int sig = 0;
765 760
766 /* we ignore the error in case we were not tracing child */
767 (void)ds_release_bts(child);
768
769 if (cfg.flags & PTRACE_BTS_O_SIGNAL) { 761 if (cfg.flags & PTRACE_BTS_O_SIGNAL) {
770 if (!cfg.signal) 762 if (!cfg.signal)
771 goto errout; 763 goto errout;
772 764
765 error = -EOPNOTSUPP;
766 goto errout;
767
773 sig = cfg.signal; 768 sig = cfg.signal;
774 ovfl = ptrace_bts_ovfl;
775 } 769 }
776 770
777 error = ds_request_bts(child, /* base = */ NULL, cfg.size, ovfl); 771 if (child->bts)
778 if (error < 0) 772 (void)ds_release_bts(child->bts);
773
774 child->bts = ds_request_bts(child, /* base = */ NULL, cfg.size,
775 ovfl, /* th = */ (size_t)-1);
776 if (IS_ERR(child->bts)) {
777 error = PTR_ERR(child->bts);
778 child->bts = NULL;
779 goto errout; 779 goto errout;
780 }
780 781
781 child->thread.bts_ovfl_signal = sig; 782 child->thread.bts_ovfl_signal = sig;
782 } 783 }
@@ -823,15 +824,15 @@ static int ptrace_bts_status(struct task_struct *child,
823 if (cfg_size < sizeof(cfg)) 824 if (cfg_size < sizeof(cfg))
824 return -EIO; 825 return -EIO;
825 826
826 error = ds_get_bts_end(child, &end); 827 error = ds_get_bts_end(child->bts, &end);
827 if (error < 0) 828 if (error < 0)
828 return error; 829 return error;
829 830
830 error = ds_access_bts(child, /* index = */ 0, &base); 831 error = ds_access_bts(child->bts, /* index = */ 0, &base);
831 if (error < 0) 832 if (error < 0)
832 return error; 833 return error;
833 834
834 error = ds_access_bts(child, /* index = */ end, &max); 835 error = ds_access_bts(child->bts, /* index = */ end, &max);
835 if (error < 0) 836 if (error < 0)
836 return error; 837 return error;
837 838
@@ -884,10 +885,7 @@ static int ptrace_bts_write_record(struct task_struct *child,
884 return -EINVAL; 885 return -EINVAL;
885 } 886 }
886 887
887 /* The writing task will be the switched-to task on a context 888 return ds_write_bts(child->bts, bts_record, bts_cfg.sizeof_bts);
888 * switch. It needs to write into the switched-from task's BTS
889 * buffer. */
890 return ds_unchecked_write_bts(child, bts_record, bts_cfg.sizeof_bts);
891} 889}
892 890
893void ptrace_bts_take_timestamp(struct task_struct *tsk, 891void ptrace_bts_take_timestamp(struct task_struct *tsk,
@@ -972,13 +970,15 @@ void ptrace_disable(struct task_struct *child)
972 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); 970 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
973#endif 971#endif
974#ifdef CONFIG_X86_PTRACE_BTS 972#ifdef CONFIG_X86_PTRACE_BTS
975 (void)ds_release_bts(child); 973 if (child->bts) {
974 (void)ds_release_bts(child->bts);
976 975
977 child->thread.debugctlmsr &= ~bts_cfg.debugctl_mask; 976 child->thread.debugctlmsr &= ~bts_cfg.debugctl_mask;
978 if (!child->thread.debugctlmsr) 977 if (!child->thread.debugctlmsr)
979 clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR); 978 clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
980 979
981 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS); 980 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
981 }
982#endif /* CONFIG_X86_PTRACE_BTS */ 982#endif /* CONFIG_X86_PTRACE_BTS */
983} 983}
984 984
@@ -1110,9 +1110,16 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
1110 (child, data, (struct ptrace_bts_config __user *)addr); 1110 (child, data, (struct ptrace_bts_config __user *)addr);
1111 break; 1111 break;
1112 1112
1113 case PTRACE_BTS_SIZE: 1113 case PTRACE_BTS_SIZE: {
1114 ret = ds_get_bts_index(child, /* pos = */ NULL); 1114 size_t size;
1115
1116 ret = ds_get_bts_index(child->bts, &size);
1117 if (ret == 0) {
1118 BUG_ON(size != (int) size);
1119 ret = (int) size;
1120 }
1115 break; 1121 break;
1122 }
1116 1123
1117 case PTRACE_BTS_GET: 1124 case PTRACE_BTS_GET:
1118 ret = ptrace_bts_read_record 1125 ret = ptrace_bts_read_record
@@ -1120,7 +1127,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
1120 break; 1127 break;
1121 1128
1122 case PTRACE_BTS_CLEAR: 1129 case PTRACE_BTS_CLEAR:
1123 ret = ds_clear_bts(child); 1130 ret = ds_clear_bts(child->bts);
1124 break; 1131 break;
1125 1132
1126 case PTRACE_BTS_DRAIN: 1133 case PTRACE_BTS_DRAIN:
diff --git a/include/linux/sched.h b/include/linux/sched.h
index bee1e93c95ad..a9780eaa6737 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -96,6 +96,7 @@ struct exec_domain;
96struct futex_pi_state; 96struct futex_pi_state;
97struct robust_list_head; 97struct robust_list_head;
98struct bio; 98struct bio;
99struct bts_tracer;
99 100
100/* 101/*
101 * List of flags we want to share for kernel threads, 102 * List of flags we want to share for kernel threads,
@@ -1161,6 +1162,14 @@ struct task_struct {
1161 struct list_head ptraced; 1162 struct list_head ptraced;
1162 struct list_head ptrace_entry; 1163 struct list_head ptrace_entry;
1163 1164
1165#ifdef CONFIG_X86_PTRACE_BTS
1166 /*
1167 * This is the tracer handle for the ptrace BTS extension.
1168 * This field actually belongs to the ptracer task.
1169 */
1170 struct bts_tracer *bts;
1171#endif /* CONFIG_X86_PTRACE_BTS */
1172
1164 /* PID/PID hash table linkage. */ 1173 /* PID/PID hash table linkage. */
1165 struct pid_link pids[PIDTYPE_MAX]; 1174 struct pid_link pids[PIDTYPE_MAX];
1166 struct list_head thread_group; 1175 struct list_head thread_group;
generated by cgit v1.2.2 (git 2.25.0) at 2024-10-09 04:33:55 -0400