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v3.15
 
  1/*
  2 *  This code provides functions to handle gcc's profiling data format
  3 *  introduced with gcc 4.7.
  4 *
  5 *  This file is based heavily on gcc_3_4.c file.
  6 *
  7 *  For a better understanding, refer to gcc source:
  8 *  gcc/gcov-io.h
  9 *  libgcc/libgcov.c
 10 *
 11 *  Uses gcc-internal data definitions.
 12 */
 13
 14#include <linux/errno.h>
 15#include <linux/slab.h>
 16#include <linux/string.h>
 17#include <linux/seq_file.h>
 18#include <linux/vmalloc.h>
 19#include "gcov.h"
 20
 
 21#define GCOV_COUNTERS			8
 
 
 
 
 
 
 
 
 
 
 22#define GCOV_TAG_FUNCTION_LENGTH	3
 23
 24static struct gcov_info *gcov_info_head;
 25
 26/**
 27 * struct gcov_ctr_info - information about counters for a single function
 28 * @num: number of counter values for this type
 29 * @values: array of counter values for this type
 30 *
 31 * This data is generated by gcc during compilation and doesn't change
 32 * at run-time with the exception of the values array.
 33 */
 34struct gcov_ctr_info {
 35	unsigned int num;
 36	gcov_type *values;
 37};
 38
 39/**
 40 * struct gcov_fn_info - profiling meta data per function
 41 * @key: comdat key
 42 * @ident: unique ident of function
 43 * @lineno_checksum: function lineo_checksum
 44 * @cfg_checksum: function cfg checksum
 45 * @ctrs: instrumented counters
 46 *
 47 * This data is generated by gcc during compilation and doesn't change
 48 * at run-time.
 49 *
 50 * Information about a single function.  This uses the trailing array
 51 * idiom. The number of counters is determined from the merge pointer
 52 * array in gcov_info.  The key is used to detect which of a set of
 53 * comdat functions was selected -- it points to the gcov_info object
 54 * of the object file containing the selected comdat function.
 55 */
 56struct gcov_fn_info {
 57	const struct gcov_info *key;
 58	unsigned int ident;
 59	unsigned int lineno_checksum;
 60	unsigned int cfg_checksum;
 61	struct gcov_ctr_info ctrs[0];
 62};
 63
 64/**
 65 * struct gcov_info - profiling data per object file
 66 * @version: gcov version magic indicating the gcc version used for compilation
 67 * @next: list head for a singly-linked list
 68 * @stamp: uniquifying time stamp
 69 * @filename: name of the associated gcov data file
 70 * @merge: merge functions (null for unused counter type)
 71 * @n_functions: number of instrumented functions
 72 * @functions: pointer to pointers to function information
 73 *
 74 * This data is generated by gcc during compilation and doesn't change
 75 * at run-time with the exception of the next pointer.
 76 */
 77struct gcov_info {
 78	unsigned int version;
 79	struct gcov_info *next;
 80	unsigned int stamp;
 81	const char *filename;
 82	void (*merge[GCOV_COUNTERS])(gcov_type *, unsigned int);
 83	unsigned int n_functions;
 84	struct gcov_fn_info **functions;
 85};
 86
 87/**
 88 * gcov_info_filename - return info filename
 89 * @info: profiling data set
 90 */
 91const char *gcov_info_filename(struct gcov_info *info)
 92{
 93	return info->filename;
 94}
 95
 96/**
 97 * gcov_info_version - return info version
 98 * @info: profiling data set
 99 */
100unsigned int gcov_info_version(struct gcov_info *info)
101{
102	return info->version;
103}
104
105/**
106 * gcov_info_next - return next profiling data set
107 * @info: profiling data set
108 *
109 * Returns next gcov_info following @info or first gcov_info in the chain if
110 * @info is %NULL.
111 */
112struct gcov_info *gcov_info_next(struct gcov_info *info)
113{
114	if (!info)
115		return gcov_info_head;
116
117	return info->next;
118}
119
120/**
121 * gcov_info_link - link/add profiling data set to the list
122 * @info: profiling data set
123 */
124void gcov_info_link(struct gcov_info *info)
125{
126	info->next = gcov_info_head;
127	gcov_info_head = info;
128}
129
130/**
131 * gcov_info_unlink - unlink/remove profiling data set from the list
132 * @prev: previous profiling data set
133 * @info: profiling data set
134 */
135void gcov_info_unlink(struct gcov_info *prev, struct gcov_info *info)
136{
137	if (prev)
138		prev->next = info->next;
139	else
140		gcov_info_head = info->next;
 
 
 
 
 
 
 
 
 
 
 
 
141}
142
143/* Symbolic links to be created for each profiling data file. */
144const struct gcov_link gcov_link[] = {
145	{ OBJ_TREE, "gcno" },	/* Link to .gcno file in $(objtree). */
146	{ 0, NULL},
147};
148
149/*
150 * Determine whether a counter is active. Doesn't change at run-time.
151 */
152static int counter_active(struct gcov_info *info, unsigned int type)
153{
154	return info->merge[type] ? 1 : 0;
155}
156
157/* Determine number of active counters. Based on gcc magic. */
158static unsigned int num_counter_active(struct gcov_info *info)
159{
160	unsigned int i;
161	unsigned int result = 0;
162
163	for (i = 0; i < GCOV_COUNTERS; i++) {
164		if (counter_active(info, i))
165			result++;
166	}
167	return result;
168}
169
170/**
171 * gcov_info_reset - reset profiling data to zero
172 * @info: profiling data set
173 */
174void gcov_info_reset(struct gcov_info *info)
175{
176	struct gcov_ctr_info *ci_ptr;
177	unsigned int fi_idx;
178	unsigned int ct_idx;
179
180	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
181		ci_ptr = info->functions[fi_idx]->ctrs;
182
183		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
184			if (!counter_active(info, ct_idx))
185				continue;
186
187			memset(ci_ptr->values, 0,
188					sizeof(gcov_type) * ci_ptr->num);
189			ci_ptr++;
190		}
191	}
192}
193
194/**
195 * gcov_info_is_compatible - check if profiling data can be added
196 * @info1: first profiling data set
197 * @info2: second profiling data set
198 *
199 * Returns non-zero if profiling data can be added, zero otherwise.
200 */
201int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2)
202{
203	return (info1->stamp == info2->stamp);
204}
205
206/**
207 * gcov_info_add - add up profiling data
208 * @dest: profiling data set to which data is added
209 * @source: profiling data set which is added
210 *
211 * Adds profiling counts of @source to @dest.
212 */
213void gcov_info_add(struct gcov_info *dst, struct gcov_info *src)
214{
215	struct gcov_ctr_info *dci_ptr;
216	struct gcov_ctr_info *sci_ptr;
217	unsigned int fi_idx;
218	unsigned int ct_idx;
219	unsigned int val_idx;
220
221	for (fi_idx = 0; fi_idx < src->n_functions; fi_idx++) {
222		dci_ptr = dst->functions[fi_idx]->ctrs;
223		sci_ptr = src->functions[fi_idx]->ctrs;
224
225		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
226			if (!counter_active(src, ct_idx))
227				continue;
228
229			for (val_idx = 0; val_idx < sci_ptr->num; val_idx++)
230				dci_ptr->values[val_idx] +=
231					sci_ptr->values[val_idx];
232
233			dci_ptr++;
234			sci_ptr++;
235		}
236	}
237}
238
239/**
240 * gcov_info_dup - duplicate profiling data set
241 * @info: profiling data set to duplicate
242 *
243 * Return newly allocated duplicate on success, %NULL on error.
244 */
245struct gcov_info *gcov_info_dup(struct gcov_info *info)
246{
247	struct gcov_info *dup;
248	struct gcov_ctr_info *dci_ptr; /* dst counter info */
249	struct gcov_ctr_info *sci_ptr; /* src counter info */
250	unsigned int active;
251	unsigned int fi_idx; /* function info idx */
252	unsigned int ct_idx; /* counter type idx */
253	size_t fi_size; /* function info size */
254	size_t cv_size; /* counter values size */
255
256	dup = kmemdup(info, sizeof(*dup), GFP_KERNEL);
257	if (!dup)
258		return NULL;
259
260	dup->next = NULL;
261	dup->filename = NULL;
262	dup->functions = NULL;
263
264	dup->filename = kstrdup(info->filename, GFP_KERNEL);
265	if (!dup->filename)
266		goto err_free;
267
268	dup->functions = kcalloc(info->n_functions,
269				 sizeof(struct gcov_fn_info *), GFP_KERNEL);
270	if (!dup->functions)
271		goto err_free;
272
273	active = num_counter_active(info);
274	fi_size = sizeof(struct gcov_fn_info);
275	fi_size += sizeof(struct gcov_ctr_info) * active;
276
277	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
278		dup->functions[fi_idx] = kzalloc(fi_size, GFP_KERNEL);
279		if (!dup->functions[fi_idx])
280			goto err_free;
281
282		*(dup->functions[fi_idx]) = *(info->functions[fi_idx]);
283
284		sci_ptr = info->functions[fi_idx]->ctrs;
285		dci_ptr = dup->functions[fi_idx]->ctrs;
286
287		for (ct_idx = 0; ct_idx < active; ct_idx++) {
288
289			cv_size = sizeof(gcov_type) * sci_ptr->num;
290
291			dci_ptr->values = vmalloc(cv_size);
292
293			if (!dci_ptr->values)
294				goto err_free;
295
296			dci_ptr->num = sci_ptr->num;
297			memcpy(dci_ptr->values, sci_ptr->values, cv_size);
298
299			sci_ptr++;
300			dci_ptr++;
301		}
302	}
303
304	return dup;
305err_free:
306	gcov_info_free(dup);
307	return NULL;
308}
309
310/**
311 * gcov_info_free - release memory for profiling data set duplicate
312 * @info: profiling data set duplicate to free
313 */
314void gcov_info_free(struct gcov_info *info)
315{
316	unsigned int active;
317	unsigned int fi_idx;
318	unsigned int ct_idx;
319	struct gcov_ctr_info *ci_ptr;
320
321	if (!info->functions)
322		goto free_info;
323
324	active = num_counter_active(info);
325
326	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
327		if (!info->functions[fi_idx])
328			continue;
329
330		ci_ptr = info->functions[fi_idx]->ctrs;
331
332		for (ct_idx = 0; ct_idx < active; ct_idx++, ci_ptr++)
333			vfree(ci_ptr->values);
334
335		kfree(info->functions[fi_idx]);
336	}
337
338free_info:
339	kfree(info->functions);
340	kfree(info->filename);
341	kfree(info);
342}
343
344#define ITER_STRIDE	PAGE_SIZE
345
346/**
347 * struct gcov_iterator - specifies current file position in logical records
348 * @info: associated profiling data
349 * @buffer: buffer containing file data
350 * @size: size of buffer
351 * @pos: current position in file
352 */
353struct gcov_iterator {
354	struct gcov_info *info;
355	void *buffer;
356	size_t size;
357	loff_t pos;
358};
359
360/**
361 * store_gcov_u32 - store 32 bit number in gcov format to buffer
362 * @buffer: target buffer or NULL
363 * @off: offset into the buffer
364 * @v: value to be stored
365 *
366 * Number format defined by gcc: numbers are recorded in the 32 bit
367 * unsigned binary form of the endianness of the machine generating the
368 * file. Returns the number of bytes stored. If @buffer is %NULL, doesn't
369 * store anything.
370 */
371static size_t store_gcov_u32(void *buffer, size_t off, u32 v)
372{
373	u32 *data;
374
375	if (buffer) {
376		data = buffer + off;
377		*data = v;
378	}
379
380	return sizeof(*data);
381}
382
383/**
384 * store_gcov_u64 - store 64 bit number in gcov format to buffer
385 * @buffer: target buffer or NULL
386 * @off: offset into the buffer
387 * @v: value to be stored
388 *
389 * Number format defined by gcc: numbers are recorded in the 32 bit
390 * unsigned binary form of the endianness of the machine generating the
391 * file. 64 bit numbers are stored as two 32 bit numbers, the low part
392 * first. Returns the number of bytes stored. If @buffer is %NULL, doesn't store
393 * anything.
394 */
395static size_t store_gcov_u64(void *buffer, size_t off, u64 v)
396{
397	u32 *data;
398
399	if (buffer) {
400		data = buffer + off;
401
402		data[0] = (v & 0xffffffffUL);
403		data[1] = (v >> 32);
404	}
405
406	return sizeof(*data) * 2;
407}
408
409/**
410 * convert_to_gcda - convert profiling data set to gcda file format
411 * @buffer: the buffer to store file data or %NULL if no data should be stored
412 * @info: profiling data set to be converted
413 *
414 * Returns the number of bytes that were/would have been stored into the buffer.
415 */
416static size_t convert_to_gcda(char *buffer, struct gcov_info *info)
417{
418	struct gcov_fn_info *fi_ptr;
419	struct gcov_ctr_info *ci_ptr;
420	unsigned int fi_idx;
421	unsigned int ct_idx;
422	unsigned int cv_idx;
423	size_t pos = 0;
424
425	/* File header. */
426	pos += store_gcov_u32(buffer, pos, GCOV_DATA_MAGIC);
427	pos += store_gcov_u32(buffer, pos, info->version);
428	pos += store_gcov_u32(buffer, pos, info->stamp);
429
430	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
431		fi_ptr = info->functions[fi_idx];
432
433		/* Function record. */
434		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION);
435		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION_LENGTH);
436		pos += store_gcov_u32(buffer, pos, fi_ptr->ident);
437		pos += store_gcov_u32(buffer, pos, fi_ptr->lineno_checksum);
438		pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);
439
440		ci_ptr = fi_ptr->ctrs;
441
442		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
443			if (!counter_active(info, ct_idx))
444				continue;
445
446			/* Counter record. */
447			pos += store_gcov_u32(buffer, pos,
448					      GCOV_TAG_FOR_COUNTER(ct_idx));
449			pos += store_gcov_u32(buffer, pos, ci_ptr->num * 2);
450
451			for (cv_idx = 0; cv_idx < ci_ptr->num; cv_idx++) {
452				pos += store_gcov_u64(buffer, pos,
453						      ci_ptr->values[cv_idx]);
454			}
455
456			ci_ptr++;
457		}
458	}
459
460	return pos;
461}
462
463/**
464 * gcov_iter_new - allocate and initialize profiling data iterator
465 * @info: profiling data set to be iterated
466 *
467 * Return file iterator on success, %NULL otherwise.
468 */
469struct gcov_iterator *gcov_iter_new(struct gcov_info *info)
470{
471	struct gcov_iterator *iter;
472
473	iter = kzalloc(sizeof(struct gcov_iterator), GFP_KERNEL);
474	if (!iter)
475		goto err_free;
476
477	iter->info = info;
478	/* Dry-run to get the actual buffer size. */
479	iter->size = convert_to_gcda(NULL, info);
480	iter->buffer = vmalloc(iter->size);
481	if (!iter->buffer)
482		goto err_free;
483
484	convert_to_gcda(iter->buffer, info);
485
486	return iter;
487
488err_free:
489	kfree(iter);
490	return NULL;
491}
492
493
494/**
495 * gcov_iter_get_info - return profiling data set for given file iterator
496 * @iter: file iterator
497 */
498void gcov_iter_free(struct gcov_iterator *iter)
499{
500	vfree(iter->buffer);
501	kfree(iter);
502}
503
504/**
505 * gcov_iter_get_info - return profiling data set for given file iterator
506 * @iter: file iterator
507 */
508struct gcov_info *gcov_iter_get_info(struct gcov_iterator *iter)
509{
510	return iter->info;
511}
512
513/**
514 * gcov_iter_start - reset file iterator to starting position
515 * @iter: file iterator
516 */
517void gcov_iter_start(struct gcov_iterator *iter)
518{
519	iter->pos = 0;
520}
521
522/**
523 * gcov_iter_next - advance file iterator to next logical record
524 * @iter: file iterator
525 *
526 * Return zero if new position is valid, non-zero if iterator has reached end.
527 */
528int gcov_iter_next(struct gcov_iterator *iter)
529{
530	if (iter->pos < iter->size)
531		iter->pos += ITER_STRIDE;
532
533	if (iter->pos >= iter->size)
534		return -EINVAL;
535
536	return 0;
537}
538
539/**
540 * gcov_iter_write - write data for current pos to seq_file
541 * @iter: file iterator
542 * @seq: seq_file handle
543 *
544 * Return zero on success, non-zero otherwise.
545 */
546int gcov_iter_write(struct gcov_iterator *iter, struct seq_file *seq)
547{
548	size_t len;
549
550	if (iter->pos >= iter->size)
551		return -EINVAL;
552
553	len = ITER_STRIDE;
554	if (iter->pos + len > iter->size)
555		len = iter->size - iter->pos;
556
557	seq_write(seq, iter->buffer + iter->pos, len);
558
559	return 0;
560}
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  This code provides functions to handle gcc's profiling data format
  4 *  introduced with gcc 4.7.
  5 *
  6 *  This file is based heavily on gcc_3_4.c file.
  7 *
  8 *  For a better understanding, refer to gcc source:
  9 *  gcc/gcov-io.h
 10 *  libgcc/libgcov.c
 11 *
 12 *  Uses gcc-internal data definitions.
 13 */
 14
 15#include <linux/errno.h>
 16#include <linux/slab.h>
 17#include <linux/string.h>
 18#include <linux/seq_file.h>
 19#include <linux/vmalloc.h>
 20#include "gcov.h"
 21
 22#if (__GNUC__ >= 10)
 23#define GCOV_COUNTERS			8
 24#elif (__GNUC__ >= 7)
 25#define GCOV_COUNTERS			9
 26#elif (__GNUC__ > 5) || (__GNUC__ == 5 && __GNUC_MINOR__ >= 1)
 27#define GCOV_COUNTERS			10
 28#elif __GNUC__ == 4 && __GNUC_MINOR__ >= 9
 29#define GCOV_COUNTERS			9
 30#else
 31#define GCOV_COUNTERS			8
 32#endif
 33
 34#define GCOV_TAG_FUNCTION_LENGTH	3
 35
 36static struct gcov_info *gcov_info_head;
 37
 38/**
 39 * struct gcov_ctr_info - information about counters for a single function
 40 * @num: number of counter values for this type
 41 * @values: array of counter values for this type
 42 *
 43 * This data is generated by gcc during compilation and doesn't change
 44 * at run-time with the exception of the values array.
 45 */
 46struct gcov_ctr_info {
 47	unsigned int num;
 48	gcov_type *values;
 49};
 50
 51/**
 52 * struct gcov_fn_info - profiling meta data per function
 53 * @key: comdat key
 54 * @ident: unique ident of function
 55 * @lineno_checksum: function lineo_checksum
 56 * @cfg_checksum: function cfg checksum
 57 * @ctrs: instrumented counters
 58 *
 59 * This data is generated by gcc during compilation and doesn't change
 60 * at run-time.
 61 *
 62 * Information about a single function.  This uses the trailing array
 63 * idiom. The number of counters is determined from the merge pointer
 64 * array in gcov_info.  The key is used to detect which of a set of
 65 * comdat functions was selected -- it points to the gcov_info object
 66 * of the object file containing the selected comdat function.
 67 */
 68struct gcov_fn_info {
 69	const struct gcov_info *key;
 70	unsigned int ident;
 71	unsigned int lineno_checksum;
 72	unsigned int cfg_checksum;
 73	struct gcov_ctr_info ctrs[];
 74};
 75
 76/**
 77 * struct gcov_info - profiling data per object file
 78 * @version: gcov version magic indicating the gcc version used for compilation
 79 * @next: list head for a singly-linked list
 80 * @stamp: uniquifying time stamp
 81 * @filename: name of the associated gcov data file
 82 * @merge: merge functions (null for unused counter type)
 83 * @n_functions: number of instrumented functions
 84 * @functions: pointer to pointers to function information
 85 *
 86 * This data is generated by gcc during compilation and doesn't change
 87 * at run-time with the exception of the next pointer.
 88 */
 89struct gcov_info {
 90	unsigned int version;
 91	struct gcov_info *next;
 92	unsigned int stamp;
 93	const char *filename;
 94	void (*merge[GCOV_COUNTERS])(gcov_type *, unsigned int);
 95	unsigned int n_functions;
 96	struct gcov_fn_info **functions;
 97};
 98
 99/**
100 * gcov_info_filename - return info filename
101 * @info: profiling data set
102 */
103const char *gcov_info_filename(struct gcov_info *info)
104{
105	return info->filename;
106}
107
108/**
109 * gcov_info_version - return info version
110 * @info: profiling data set
111 */
112unsigned int gcov_info_version(struct gcov_info *info)
113{
114	return info->version;
115}
116
117/**
118 * gcov_info_next - return next profiling data set
119 * @info: profiling data set
120 *
121 * Returns next gcov_info following @info or first gcov_info in the chain if
122 * @info is %NULL.
123 */
124struct gcov_info *gcov_info_next(struct gcov_info *info)
125{
126	if (!info)
127		return gcov_info_head;
128
129	return info->next;
130}
131
132/**
133 * gcov_info_link - link/add profiling data set to the list
134 * @info: profiling data set
135 */
136void gcov_info_link(struct gcov_info *info)
137{
138	info->next = gcov_info_head;
139	gcov_info_head = info;
140}
141
142/**
143 * gcov_info_unlink - unlink/remove profiling data set from the list
144 * @prev: previous profiling data set
145 * @info: profiling data set
146 */
147void gcov_info_unlink(struct gcov_info *prev, struct gcov_info *info)
148{
149	if (prev)
150		prev->next = info->next;
151	else
152		gcov_info_head = info->next;
153}
154
155/**
156 * gcov_info_within_module - check if a profiling data set belongs to a module
157 * @info: profiling data set
158 * @mod: module
159 *
160 * Returns true if profiling data belongs module, false otherwise.
161 */
162bool gcov_info_within_module(struct gcov_info *info, struct module *mod)
163{
164	return within_module((unsigned long)info, mod);
165}
166
167/* Symbolic links to be created for each profiling data file. */
168const struct gcov_link gcov_link[] = {
169	{ OBJ_TREE, "gcno" },	/* Link to .gcno file in $(objtree). */
170	{ 0, NULL},
171};
172
173/*
174 * Determine whether a counter is active. Doesn't change at run-time.
175 */
176static int counter_active(struct gcov_info *info, unsigned int type)
177{
178	return info->merge[type] ? 1 : 0;
179}
180
181/* Determine number of active counters. Based on gcc magic. */
182static unsigned int num_counter_active(struct gcov_info *info)
183{
184	unsigned int i;
185	unsigned int result = 0;
186
187	for (i = 0; i < GCOV_COUNTERS; i++) {
188		if (counter_active(info, i))
189			result++;
190	}
191	return result;
192}
193
194/**
195 * gcov_info_reset - reset profiling data to zero
196 * @info: profiling data set
197 */
198void gcov_info_reset(struct gcov_info *info)
199{
200	struct gcov_ctr_info *ci_ptr;
201	unsigned int fi_idx;
202	unsigned int ct_idx;
203
204	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
205		ci_ptr = info->functions[fi_idx]->ctrs;
206
207		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
208			if (!counter_active(info, ct_idx))
209				continue;
210
211			memset(ci_ptr->values, 0,
212					sizeof(gcov_type) * ci_ptr->num);
213			ci_ptr++;
214		}
215	}
216}
217
218/**
219 * gcov_info_is_compatible - check if profiling data can be added
220 * @info1: first profiling data set
221 * @info2: second profiling data set
222 *
223 * Returns non-zero if profiling data can be added, zero otherwise.
224 */
225int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2)
226{
227	return (info1->stamp == info2->stamp);
228}
229
230/**
231 * gcov_info_add - add up profiling data
232 * @dest: profiling data set to which data is added
233 * @source: profiling data set which is added
234 *
235 * Adds profiling counts of @source to @dest.
236 */
237void gcov_info_add(struct gcov_info *dst, struct gcov_info *src)
238{
239	struct gcov_ctr_info *dci_ptr;
240	struct gcov_ctr_info *sci_ptr;
241	unsigned int fi_idx;
242	unsigned int ct_idx;
243	unsigned int val_idx;
244
245	for (fi_idx = 0; fi_idx < src->n_functions; fi_idx++) {
246		dci_ptr = dst->functions[fi_idx]->ctrs;
247		sci_ptr = src->functions[fi_idx]->ctrs;
248
249		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
250			if (!counter_active(src, ct_idx))
251				continue;
252
253			for (val_idx = 0; val_idx < sci_ptr->num; val_idx++)
254				dci_ptr->values[val_idx] +=
255					sci_ptr->values[val_idx];
256
257			dci_ptr++;
258			sci_ptr++;
259		}
260	}
261}
262
263/**
264 * gcov_info_dup - duplicate profiling data set
265 * @info: profiling data set to duplicate
266 *
267 * Return newly allocated duplicate on success, %NULL on error.
268 */
269struct gcov_info *gcov_info_dup(struct gcov_info *info)
270{
271	struct gcov_info *dup;
272	struct gcov_ctr_info *dci_ptr; /* dst counter info */
273	struct gcov_ctr_info *sci_ptr; /* src counter info */
274	unsigned int active;
275	unsigned int fi_idx; /* function info idx */
276	unsigned int ct_idx; /* counter type idx */
277	size_t fi_size; /* function info size */
278	size_t cv_size; /* counter values size */
279
280	dup = kmemdup(info, sizeof(*dup), GFP_KERNEL);
281	if (!dup)
282		return NULL;
283
284	dup->next = NULL;
285	dup->filename = NULL;
286	dup->functions = NULL;
287
288	dup->filename = kstrdup(info->filename, GFP_KERNEL);
289	if (!dup->filename)
290		goto err_free;
291
292	dup->functions = kcalloc(info->n_functions,
293				 sizeof(struct gcov_fn_info *), GFP_KERNEL);
294	if (!dup->functions)
295		goto err_free;
296
297	active = num_counter_active(info);
298	fi_size = sizeof(struct gcov_fn_info);
299	fi_size += sizeof(struct gcov_ctr_info) * active;
300
301	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
302		dup->functions[fi_idx] = kzalloc(fi_size, GFP_KERNEL);
303		if (!dup->functions[fi_idx])
304			goto err_free;
305
306		*(dup->functions[fi_idx]) = *(info->functions[fi_idx]);
307
308		sci_ptr = info->functions[fi_idx]->ctrs;
309		dci_ptr = dup->functions[fi_idx]->ctrs;
310
311		for (ct_idx = 0; ct_idx < active; ct_idx++) {
312
313			cv_size = sizeof(gcov_type) * sci_ptr->num;
314
315			dci_ptr->values = vmalloc(cv_size);
316
317			if (!dci_ptr->values)
318				goto err_free;
319
320			dci_ptr->num = sci_ptr->num;
321			memcpy(dci_ptr->values, sci_ptr->values, cv_size);
322
323			sci_ptr++;
324			dci_ptr++;
325		}
326	}
327
328	return dup;
329err_free:
330	gcov_info_free(dup);
331	return NULL;
332}
333
334/**
335 * gcov_info_free - release memory for profiling data set duplicate
336 * @info: profiling data set duplicate to free
337 */
338void gcov_info_free(struct gcov_info *info)
339{
340	unsigned int active;
341	unsigned int fi_idx;
342	unsigned int ct_idx;
343	struct gcov_ctr_info *ci_ptr;
344
345	if (!info->functions)
346		goto free_info;
347
348	active = num_counter_active(info);
349
350	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
351		if (!info->functions[fi_idx])
352			continue;
353
354		ci_ptr = info->functions[fi_idx]->ctrs;
355
356		for (ct_idx = 0; ct_idx < active; ct_idx++, ci_ptr++)
357			vfree(ci_ptr->values);
358
359		kfree(info->functions[fi_idx]);
360	}
361
362free_info:
363	kfree(info->functions);
364	kfree(info->filename);
365	kfree(info);
366}
367
368#define ITER_STRIDE	PAGE_SIZE
369
370/**
371 * struct gcov_iterator - specifies current file position in logical records
372 * @info: associated profiling data
373 * @buffer: buffer containing file data
374 * @size: size of buffer
375 * @pos: current position in file
376 */
377struct gcov_iterator {
378	struct gcov_info *info;
379	void *buffer;
380	size_t size;
381	loff_t pos;
382};
383
384/**
385 * store_gcov_u32 - store 32 bit number in gcov format to buffer
386 * @buffer: target buffer or NULL
387 * @off: offset into the buffer
388 * @v: value to be stored
389 *
390 * Number format defined by gcc: numbers are recorded in the 32 bit
391 * unsigned binary form of the endianness of the machine generating the
392 * file. Returns the number of bytes stored. If @buffer is %NULL, doesn't
393 * store anything.
394 */
395static size_t store_gcov_u32(void *buffer, size_t off, u32 v)
396{
397	u32 *data;
398
399	if (buffer) {
400		data = buffer + off;
401		*data = v;
402	}
403
404	return sizeof(*data);
405}
406
407/**
408 * store_gcov_u64 - store 64 bit number in gcov format to buffer
409 * @buffer: target buffer or NULL
410 * @off: offset into the buffer
411 * @v: value to be stored
412 *
413 * Number format defined by gcc: numbers are recorded in the 32 bit
414 * unsigned binary form of the endianness of the machine generating the
415 * file. 64 bit numbers are stored as two 32 bit numbers, the low part
416 * first. Returns the number of bytes stored. If @buffer is %NULL, doesn't store
417 * anything.
418 */
419static size_t store_gcov_u64(void *buffer, size_t off, u64 v)
420{
421	u32 *data;
422
423	if (buffer) {
424		data = buffer + off;
425
426		data[0] = (v & 0xffffffffUL);
427		data[1] = (v >> 32);
428	}
429
430	return sizeof(*data) * 2;
431}
432
433/**
434 * convert_to_gcda - convert profiling data set to gcda file format
435 * @buffer: the buffer to store file data or %NULL if no data should be stored
436 * @info: profiling data set to be converted
437 *
438 * Returns the number of bytes that were/would have been stored into the buffer.
439 */
440static size_t convert_to_gcda(char *buffer, struct gcov_info *info)
441{
442	struct gcov_fn_info *fi_ptr;
443	struct gcov_ctr_info *ci_ptr;
444	unsigned int fi_idx;
445	unsigned int ct_idx;
446	unsigned int cv_idx;
447	size_t pos = 0;
448
449	/* File header. */
450	pos += store_gcov_u32(buffer, pos, GCOV_DATA_MAGIC);
451	pos += store_gcov_u32(buffer, pos, info->version);
452	pos += store_gcov_u32(buffer, pos, info->stamp);
453
454	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
455		fi_ptr = info->functions[fi_idx];
456
457		/* Function record. */
458		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION);
459		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION_LENGTH);
460		pos += store_gcov_u32(buffer, pos, fi_ptr->ident);
461		pos += store_gcov_u32(buffer, pos, fi_ptr->lineno_checksum);
462		pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);
463
464		ci_ptr = fi_ptr->ctrs;
465
466		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
467			if (!counter_active(info, ct_idx))
468				continue;
469
470			/* Counter record. */
471			pos += store_gcov_u32(buffer, pos,
472					      GCOV_TAG_FOR_COUNTER(ct_idx));
473			pos += store_gcov_u32(buffer, pos, ci_ptr->num * 2);
474
475			for (cv_idx = 0; cv_idx < ci_ptr->num; cv_idx++) {
476				pos += store_gcov_u64(buffer, pos,
477						      ci_ptr->values[cv_idx]);
478			}
479
480			ci_ptr++;
481		}
482	}
483
484	return pos;
485}
486
487/**
488 * gcov_iter_new - allocate and initialize profiling data iterator
489 * @info: profiling data set to be iterated
490 *
491 * Return file iterator on success, %NULL otherwise.
492 */
493struct gcov_iterator *gcov_iter_new(struct gcov_info *info)
494{
495	struct gcov_iterator *iter;
496
497	iter = kzalloc(sizeof(struct gcov_iterator), GFP_KERNEL);
498	if (!iter)
499		goto err_free;
500
501	iter->info = info;
502	/* Dry-run to get the actual buffer size. */
503	iter->size = convert_to_gcda(NULL, info);
504	iter->buffer = vmalloc(iter->size);
505	if (!iter->buffer)
506		goto err_free;
507
508	convert_to_gcda(iter->buffer, info);
509
510	return iter;
511
512err_free:
513	kfree(iter);
514	return NULL;
515}
516
517
518/**
519 * gcov_iter_get_info - return profiling data set for given file iterator
520 * @iter: file iterator
521 */
522void gcov_iter_free(struct gcov_iterator *iter)
523{
524	vfree(iter->buffer);
525	kfree(iter);
526}
527
528/**
529 * gcov_iter_get_info - return profiling data set for given file iterator
530 * @iter: file iterator
531 */
532struct gcov_info *gcov_iter_get_info(struct gcov_iterator *iter)
533{
534	return iter->info;
535}
536
537/**
538 * gcov_iter_start - reset file iterator to starting position
539 * @iter: file iterator
540 */
541void gcov_iter_start(struct gcov_iterator *iter)
542{
543	iter->pos = 0;
544}
545
546/**
547 * gcov_iter_next - advance file iterator to next logical record
548 * @iter: file iterator
549 *
550 * Return zero if new position is valid, non-zero if iterator has reached end.
551 */
552int gcov_iter_next(struct gcov_iterator *iter)
553{
554	if (iter->pos < iter->size)
555		iter->pos += ITER_STRIDE;
556
557	if (iter->pos >= iter->size)
558		return -EINVAL;
559
560	return 0;
561}
562
563/**
564 * gcov_iter_write - write data for current pos to seq_file
565 * @iter: file iterator
566 * @seq: seq_file handle
567 *
568 * Return zero on success, non-zero otherwise.
569 */
570int gcov_iter_write(struct gcov_iterator *iter, struct seq_file *seq)
571{
572	size_t len;
573
574	if (iter->pos >= iter->size)
575		return -EINVAL;
576
577	len = ITER_STRIDE;
578	if (iter->pos + len > iter->size)
579		len = iter->size - iter->pos;
580
581	seq_write(seq, iter->buffer + iter->pos, len);
582
583	return 0;
584}