[linux.git] / kernel / gcov / gcc_4_7.c

/*
 *  This code provides functions to handle gcc's profiling data format
 *  introduced with gcc 4.7.
 *
 *  This file is based heavily on gcc_3_4.c file.
 *
 *  For a better understanding, refer to gcc source:
 *  gcc/gcov-io.h
 *  libgcc/libgcov.c
 *
 *  Uses gcc-internal data definitions.
 */

#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/seq_file.h>
#include <linux/vmalloc.h>
#include "gcov.h"

#if (__GNUC__ >= 7)
#define GCOV_COUNTERS			9
#elif (__GNUC__ > 5) || (__GNUC__ == 5 && __GNUC_MINOR__ >= 1)
#define GCOV_COUNTERS			10
#elif __GNUC__ == 4 && __GNUC_MINOR__ >= 9
#define GCOV_COUNTERS			9
#else
#define GCOV_COUNTERS			8
#endif

#define GCOV_TAG_FUNCTION_LENGTH	3

static struct gcov_info *gcov_info_head;

/**
 * struct gcov_ctr_info - information about counters for a single function
 * @num: number of counter values for this type
 * @values: array of counter values for this type
 *
 * This data is generated by gcc during compilation and doesn't change
 * at run-time with the exception of the values array.
 */
struct gcov_ctr_info {
	unsigned int num;
	gcov_type *values;
};

/**
 * struct gcov_fn_info - profiling meta data per function
 * @key: comdat key
 * @ident: unique ident of function
 * @lineno_checksum: function lineo_checksum
 * @cfg_checksum: function cfg checksum
 * @ctrs: instrumented counters
 *
 * This data is generated by gcc during compilation and doesn't change
 * at run-time.
 *
 * Information about a single function.  This uses the trailing array
 * idiom. The number of counters is determined from the merge pointer
 * array in gcov_info.  The key is used to detect which of a set of
 * comdat functions was selected -- it points to the gcov_info object
 * of the object file containing the selected comdat function.
 */
struct gcov_fn_info {
	const struct gcov_info *key;
	unsigned int ident;
	unsigned int lineno_checksum;
	unsigned int cfg_checksum;
	struct gcov_ctr_info ctrs[0];
};

/**
 * struct gcov_info - profiling data per object file
 * @version: gcov version magic indicating the gcc version used for compilation
 * @next: list head for a singly-linked list
 * @stamp: uniquifying time stamp
 * @filename: name of the associated gcov data file
 * @merge: merge functions (null for unused counter type)
 * @n_functions: number of instrumented functions
 * @functions: pointer to pointers to function information
 *
 * This data is generated by gcc during compilation and doesn't change
 * at run-time with the exception of the next pointer.
 */
struct gcov_info {
	unsigned int version;
	struct gcov_info *next;
	unsigned int stamp;
	const char *filename;
	void (*merge[GCOV_COUNTERS])(gcov_type *, unsigned int);
	unsigned int n_functions;
	struct gcov_fn_info **functions;
};

/**
 * gcov_info_filename - return info filename
 * @info: profiling data set
 */
const char *gcov_info_filename(struct gcov_info *info)
{
	return info->filename;
}

/**
 * gcov_info_version - return info version
 * @info: profiling data set
 */
unsigned int gcov_info_version(struct gcov_info *info)
{
	return info->version;
}

/**
 * gcov_info_next - return next profiling data set
 * @info: profiling data set
 *
 * Returns next gcov_info following @info or first gcov_info in the chain if
 * @info is %NULL.
 */
struct gcov_info *gcov_info_next(struct gcov_info *info)
{
	if (!info)
		return gcov_info_head;

	return info->next;
}

/**
 * gcov_info_link - link/add profiling data set to the list
 * @info: profiling data set
 */
void gcov_info_link(struct gcov_info *info)
{
	info->next = gcov_info_head;
	gcov_info_head = info;
}

/**
 * gcov_info_unlink - unlink/remove profiling data set from the list
 * @prev: previous profiling data set
 * @info: profiling data set
 */
void gcov_info_unlink(struct gcov_info *prev, struct gcov_info *info)
{
	if (prev)
		prev->next = info->next;
	else
		gcov_info_head = info->next;
}

/* Symbolic links to be created for each profiling data file. */
const struct gcov_link gcov_link[] = {
	{ OBJ_TREE, "gcno" },	/* Link to .gcno file in $(objtree). */
	{ 0, NULL},
};

/*
 * Determine whether a counter is active. Doesn't change at run-time.
 */
static int counter_active(struct gcov_info *info, unsigned int type)
{
	return info->merge[type] ? 1 : 0;
}

/* Determine number of active counters. Based on gcc magic. */
static unsigned int num_counter_active(struct gcov_info *info)
{
	unsigned int i;
	unsigned int result = 0;

	for (i = 0; i < GCOV_COUNTERS; i++) {
		if (counter_active(info, i))
			result++;
	}
	return result;
}

/**
 * gcov_info_reset - reset profiling data to zero
 * @info: profiling data set
 */
void gcov_info_reset(struct gcov_info *info)
{
	struct gcov_ctr_info *ci_ptr;
	unsigned int fi_idx;
	unsigned int ct_idx;

	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
		ci_ptr = info->functions[fi_idx]->ctrs;

		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
			if (!counter_active(info, ct_idx))
				continue;

			memset(ci_ptr->values, 0,
					sizeof(gcov_type) * ci_ptr->num);
			ci_ptr++;
		}
	}
}

/**
 * gcov_info_is_compatible - check if profiling data can be added
 * @info1: first profiling data set
 * @info2: second profiling data set
 *
 * Returns non-zero if profiling data can be added, zero otherwise.
 */
int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2)
{
	return (info1->stamp == info2->stamp);
}

/**
 * gcov_info_add - add up profiling data
 * @dest: profiling data set to which data is added
 * @source: profiling data set which is added
 *
 * Adds profiling counts of @source to @dest.
 */
void gcov_info_add(struct gcov_info *dst, struct gcov_info *src)
{
	struct gcov_ctr_info *dci_ptr;
	struct gcov_ctr_info *sci_ptr;
	unsigned int fi_idx;
	unsigned int ct_idx;
	unsigned int val_idx;

	for (fi_idx = 0; fi_idx < src->n_functions; fi_idx++) {
		dci_ptr = dst->functions[fi_idx]->ctrs;
		sci_ptr = src->functions[fi_idx]->ctrs;

		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
			if (!counter_active(src, ct_idx))
				continue;

			for (val_idx = 0; val_idx < sci_ptr->num; val_idx++)
				dci_ptr->values[val_idx] +=
					sci_ptr->values[val_idx];

			dci_ptr++;
			sci_ptr++;
		}
	}
}

/**
 * gcov_info_dup - duplicate profiling data set
 * @info: profiling data set to duplicate
 *
 * Return newly allocated duplicate on success, %NULL on error.
 */
struct gcov_info *gcov_info_dup(struct gcov_info *info)
{
	struct gcov_info *dup;
	struct gcov_ctr_info *dci_ptr; /* dst counter info */
	struct gcov_ctr_info *sci_ptr; /* src counter info */
	unsigned int active;
	unsigned int fi_idx; /* function info idx */
	unsigned int ct_idx; /* counter type idx */
	size_t fi_size; /* function info size */
	size_t cv_size; /* counter values size */

	dup = kmemdup(info, sizeof(*dup), GFP_KERNEL);
	if (!dup)
		return NULL;

	dup->next = NULL;
	dup->filename = NULL;
	dup->functions = NULL;

	dup->filename = kstrdup(info->filename, GFP_KERNEL);
	if (!dup->filename)
		goto err_free;

	dup->functions = kcalloc(info->n_functions,
				 sizeof(struct gcov_fn_info *), GFP_KERNEL);
	if (!dup->functions)
		goto err_free;

	active = num_counter_active(info);
	fi_size = sizeof(struct gcov_fn_info);
	fi_size += sizeof(struct gcov_ctr_info) * active;

	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
		dup->functions[fi_idx] = kzalloc(fi_size, GFP_KERNEL);
		if (!dup->functions[fi_idx])
			goto err_free;

		*(dup->functions[fi_idx]) = *(info->functions[fi_idx]);

		sci_ptr = info->functions[fi_idx]->ctrs;
		dci_ptr = dup->functions[fi_idx]->ctrs;

		for (ct_idx = 0; ct_idx < active; ct_idx++) {

			cv_size = sizeof(gcov_type) * sci_ptr->num;

			dci_ptr->values = vmalloc(cv_size);

			if (!dci_ptr->values)
				goto err_free;

			dci_ptr->num = sci_ptr->num;
			memcpy(dci_ptr->values, sci_ptr->values, cv_size);

			sci_ptr++;
			dci_ptr++;
		}
	}

	return dup;
err_free:
	gcov_info_free(dup);
	return NULL;
}

/**
 * gcov_info_free - release memory for profiling data set duplicate
 * @info: profiling data set duplicate to free
 */
void gcov_info_free(struct gcov_info *info)
{
	unsigned int active;
	unsigned int fi_idx;
	unsigned int ct_idx;
	struct gcov_ctr_info *ci_ptr;

	if (!info->functions)
		goto free_info;

	active = num_counter_active(info);

	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
		if (!info->functions[fi_idx])
			continue;

		ci_ptr = info->functions[fi_idx]->ctrs;

		for (ct_idx = 0; ct_idx < active; ct_idx++, ci_ptr++)
			vfree(ci_ptr->values);

		kfree(info->functions[fi_idx]);
	}

free_info:
	kfree(info->functions);
	kfree(info->filename);
	kfree(info);
}

#define ITER_STRIDE	PAGE_SIZE

/**
 * struct gcov_iterator - specifies current file position in logical records
 * @info: associated profiling data
 * @buffer: buffer containing file data
 * @size: size of buffer
 * @pos: current position in file
 */
struct gcov_iterator {
	struct gcov_info *info;
	void *buffer;
	size_t size;
	loff_t pos;
};

/**
 * store_gcov_u32 - store 32 bit number in gcov format to buffer
 * @buffer: target buffer or NULL
 * @off: offset into the buffer
 * @v: value to be stored
 *
 * Number format defined by gcc: numbers are recorded in the 32 bit
 * unsigned binary form of the endianness of the machine generating the
 * file. Returns the number of bytes stored. If @buffer is %NULL, doesn't
 * store anything.
 */
static size_t store_gcov_u32(void *buffer, size_t off, u32 v)
{
	u32 *data;

	if (buffer) {
		data = buffer + off;
		*data = v;
	}

	return sizeof(*data);
}

/**
 * store_gcov_u64 - store 64 bit number in gcov format to buffer
 * @buffer: target buffer or NULL
 * @off: offset into the buffer
 * @v: value to be stored
 *
 * Number format defined by gcc: numbers are recorded in the 32 bit
 * unsigned binary form of the endianness of the machine generating the
 * file. 64 bit numbers are stored as two 32 bit numbers, the low part
 * first. Returns the number of bytes stored. If @buffer is %NULL, doesn't store
 * anything.
 */
static size_t store_gcov_u64(void *buffer, size_t off, u64 v)
{
	u32 *data;

	if (buffer) {
		data = buffer + off;

		data[0] = (v & 0xffffffffUL);
		data[1] = (v >> 32);
	}

	return sizeof(*data) * 2;
}

/**
 * convert_to_gcda - convert profiling data set to gcda file format
 * @buffer: the buffer to store file data or %NULL if no data should be stored
 * @info: profiling data set to be converted
 *
 * Returns the number of bytes that were/would have been stored into the buffer.
 */
static size_t convert_to_gcda(char *buffer, struct gcov_info *info)
{
	struct gcov_fn_info *fi_ptr;
	struct gcov_ctr_info *ci_ptr;
	unsigned int fi_idx;
	unsigned int ct_idx;
	unsigned int cv_idx;
	size_t pos = 0;

	/* File header. */
	pos += store_gcov_u32(buffer, pos, GCOV_DATA_MAGIC);
	pos += store_gcov_u32(buffer, pos, info->version);
	pos += store_gcov_u32(buffer, pos, info->stamp);

	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
		fi_ptr = info->functions[fi_idx];

		/* Function record. */
		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION);
		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION_LENGTH);
		pos += store_gcov_u32(buffer, pos, fi_ptr->ident);
		pos += store_gcov_u32(buffer, pos, fi_ptr->lineno_checksum);
		pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);

		ci_ptr = fi_ptr->ctrs;

		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
			if (!counter_active(info, ct_idx))
				continue;

			/* Counter record. */
			pos += store_gcov_u32(buffer, pos,
					      GCOV_TAG_FOR_COUNTER(ct_idx));
			pos += store_gcov_u32(buffer, pos, ci_ptr->num * 2);

			for (cv_idx = 0; cv_idx < ci_ptr->num; cv_idx++) {
				pos += store_gcov_u64(buffer, pos,
						      ci_ptr->values[cv_idx]);
			}

			ci_ptr++;
		}
	}

	return pos;
}

/**
 * gcov_iter_new - allocate and initialize profiling data iterator
 * @info: profiling data set to be iterated
 *
 * Return file iterator on success, %NULL otherwise.
 */
struct gcov_iterator *gcov_iter_new(struct gcov_info *info)
{
	struct gcov_iterator *iter;

	iter = kzalloc(sizeof(struct gcov_iterator), GFP_KERNEL);
	if (!iter)
		goto err_free;

	iter->info = info;
	/* Dry-run to get the actual buffer size. */
	iter->size = convert_to_gcda(NULL, info);
	iter->buffer = vmalloc(iter->size);
	if (!iter->buffer)
		goto err_free;

	convert_to_gcda(iter->buffer, info);

	return iter;

err_free:
	kfree(iter);
	return NULL;
}


/**
 * gcov_iter_get_info - return profiling data set for given file iterator
 * @iter: file iterator
 */
void gcov_iter_free(struct gcov_iterator *iter)
{
	vfree(iter->buffer);
	kfree(iter);
}

/**
 * gcov_iter_get_info - return profiling data set for given file iterator
 * @iter: file iterator
 */
struct gcov_info *gcov_iter_get_info(struct gcov_iterator *iter)
{
	return iter->info;
}

/**
 * gcov_iter_start - reset file iterator to starting position
 * @iter: file iterator
 */
void gcov_iter_start(struct gcov_iterator *iter)
{
	iter->pos = 0;
}

/**
 * gcov_iter_next - advance file iterator to next logical record
 * @iter: file iterator
 *
 * Return zero if new position is valid, non-zero if iterator has reached end.
 */
int gcov_iter_next(struct gcov_iterator *iter)
{
	if (iter->pos < iter->size)
		iter->pos += ITER_STRIDE;

	if (iter->pos >= iter->size)
		return -EINVAL;

	return 0;
}

/**
 * gcov_iter_write - write data for current pos to seq_file
 * @iter: file iterator
 * @seq: seq_file handle
 *
 * Return zero on success, non-zero otherwise.
 */
int gcov_iter_write(struct gcov_iterator *iter, struct seq_file *seq)
{
	size_t len;

	if (iter->pos >= iter->size)
		return -EINVAL;

	len = ITER_STRIDE;
	if (iter->pos + len > iter->size)
		len = iter->size - iter->pos;

	seq_write(seq, iter->buffer + iter->pos, len);

	return 0;
}
Commit	Line	Data
5f41ea03 FH	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
05384213 ML	21	#if (__GNUC__ >= 7)
	22	#define GCOV_COUNTERS 9
	23	#elif (__GNUC__ > 5) \|\| (__GNUC__ == 5 && __GNUC_MINOR__ >= 1)
3e44c471 LS	24	#define GCOV_COUNTERS 10
3e44c471 LS	25	#elif __GNUC__ == 4 && __GNUC_MINOR__ >= 9
a992bf83 YP	26	#define GCOV_COUNTERS 9
a992bf83 YP	27	#else
5f41ea03	28	#define GCOV_COUNTERS 8
a992bf83 YP	29	#endif
a992bf83 YP	30
5f41ea03 FH	31	#define GCOV_TAG_FUNCTION_LENGTH 3
	32
	33	static struct gcov_info *gcov_info_head;
	34
	35	/**
	36	* struct gcov_ctr_info - information about counters for a single function
	37	* @num: number of counter values for this type
	38	* @values: array of counter values for this type
	39	*
	40	* This data is generated by gcc during compilation and doesn't change
	41	* at run-time with the exception of the values array.
	42	*/
	43	struct gcov_ctr_info {
	44	unsigned int num;
	45	gcov_type *values;
	46	};
	47
	48	/**
	49	* struct gcov_fn_info - profiling meta data per function
	50	* @key: comdat key
	51	* @ident: unique ident of function
	52	* @lineno_checksum: function lineo_checksum
	53	* @cfg_checksum: function cfg checksum
	54	* @ctrs: instrumented counters
	55	*
	56	* This data is generated by gcc during compilation and doesn't change
	57	* at run-time.
	58	*
	59	* Information about a single function. This uses the trailing array
	60	* idiom. The number of counters is determined from the merge pointer
	61	* array in gcov_info. The key is used to detect which of a set of
	62	* comdat functions was selected -- it points to the gcov_info object
	63	* of the object file containing the selected comdat function.
	64	*/
	65	struct gcov_fn_info {
	66	const struct gcov_info *key;
	67	unsigned int ident;
	68	unsigned int lineno_checksum;
	69	unsigned int cfg_checksum;
	70	struct gcov_ctr_info ctrs[0];
	71	};
	72
	73	/**
	74	* struct gcov_info - profiling data per object file
	75	* @version: gcov version magic indicating the gcc version used for compilation
	76	* @next: list head for a singly-linked list
	77	* @stamp: uniquifying time stamp
	78	* @filename: name of the associated gcov data file
	79	* @merge: merge functions (null for unused counter type)
	80	* @n_functions: number of instrumented functions
	81	* @functions: pointer to pointers to function information
	82	*
	83	* This data is generated by gcc during compilation and doesn't change
	84	* at run-time with the exception of the next pointer.
	85	*/
	86	struct gcov_info {
	87	unsigned int version;
	88	struct gcov_info *next;
	89	unsigned int stamp;
	90	const char *filename;
	91	void (merge[GCOV_COUNTERS])(gcov_type , unsigned int);
	92	unsigned int n_functions;
	93	struct gcov_fn_info **functions;
	94	};
95
96	/**
97	* gcov_info_filename - return info filename
98	* @info: profiling data set
99	*/
100	const char gcov_info_filename(struct gcov_info info)
101	{
102	return info->filename;
103	}
104
105	/**
106	* gcov_info_version - return info version
107	* @info: profiling data set
108	*/
109	unsigned int gcov_info_version(struct gcov_info *info)
110	{
111	return info->version;
112	}
113
114	/**
115	* gcov_info_next - return next profiling data set
116	* @info: profiling data set
117	*
118	* Returns next gcov_info following @info or first gcov_info in the chain if
119	* @info is %NULL.
120	*/
121	struct gcov_info gcov_info_next(struct gcov_info info)
122	{
123	if (!info)
124	return gcov_info_head;
125
126	return info->next;
127	}
128
129	/**
130	* gcov_info_link - link/add profiling data set to the list
131	* @info: profiling data set
132	*/
133	void gcov_info_link(struct gcov_info *info)
134	{
135	info->next = gcov_info_head;
136	gcov_info_head = info;
137	}
138
139	/**
140	* gcov_info_unlink - unlink/remove profiling data set from the list
141	* @prev: previous profiling data set
142	* @info: profiling data set
143	*/
144	void gcov_info_unlink(struct gcov_info prev, struct gcov_info info)
145	{
146	if (prev)
147	prev->next = info->next;
148	else
149	gcov_info_head = info->next;
150	}
151
152	/* Symbolic links to be created for each profiling data file. */
153	const struct gcov_link gcov_link[] = {
154	{ OBJ_TREE, "gcno" }, /* Link to .gcno file in $(objtree). */
155	{ 0, NULL},
156	};
157
158	/*
159	* Determine whether a counter is active. Doesn't change at run-time.
160	*/
161	static int counter_active(struct gcov_info *info, unsigned int type)
162	{
163	return info->merge[type] ? 1 : 0;
164	}
165
166	/* Determine number of active counters. Based on gcc magic. */
167	static unsigned int num_counter_active(struct gcov_info *info)
168	{
169	unsigned int i;
170	unsigned int result = 0;
171
172	for (i = 0; i < GCOV_COUNTERS; i++) {
173	if (counter_active(info, i))
174	result++;
175	}
176	return result;
177	}
178
179	/**
180	* gcov_info_reset - reset profiling data to zero
181	* @info: profiling data set
182	*/
183	void gcov_info_reset(struct gcov_info *info)
184	{
185	struct gcov_ctr_info *ci_ptr;
186	unsigned int fi_idx;
187	unsigned int ct_idx;
188
189	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
190	ci_ptr = info->functions[fi_idx]->ctrs;
191
192	for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
193	if (!counter_active(info, ct_idx))
194	continue;
195
196	memset(ci_ptr->values, 0,
197	sizeof(gcov_type) * ci_ptr->num);
198	ci_ptr++;
199	}
200	}
201	}
202
203	/**
204	* gcov_info_is_compatible - check if profiling data can be added
205	* @info1: first profiling data set
206	* @info2: second profiling data set
207	*
208	* Returns non-zero if profiling data can be added, zero otherwise.
209	*/
210	int gcov_info_is_compatible(struct gcov_info info1, struct gcov_info info2)
211	{
212	return (info1->stamp == info2->stamp);
213	}
214
215	/**
216	* gcov_info_add - add up profiling data
217	* @dest: profiling data set to which data is added
218	* @source: profiling data set which is added
219	*
220	* Adds profiling counts of @source to @dest.
221	*/
222	void gcov_info_add(struct gcov_info dst, struct gcov_info src)
223	{
224	struct gcov_ctr_info *dci_ptr;
225	struct gcov_ctr_info *sci_ptr;
226	unsigned int fi_idx;
227	unsigned int ct_idx;
228	unsigned int val_idx;
229
230	for (fi_idx = 0; fi_idx < src->n_functions; fi_idx++) {
231	dci_ptr = dst->functions[fi_idx]->ctrs;
232	sci_ptr = src->functions[fi_idx]->ctrs;
233
234	for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
235	if (!counter_active(src, ct_idx))
236	continue;
237
238	for (val_idx = 0; val_idx < sci_ptr->num; val_idx++)
239	dci_ptr->values[val_idx] +=
240	sci_ptr->values[val_idx];
241
242	dci_ptr++;
243	sci_ptr++;
244	}
245	}
246	}
247
248	/**
249	* gcov_info_dup - duplicate profiling data set
250	* @info: profiling data set to duplicate
251	*
252	* Return newly allocated duplicate on success, %NULL on error.
253	*/
254	struct gcov_info gcov_info_dup(struct gcov_info info)
255	{
256	struct gcov_info *dup;
257	struct gcov_ctr_info dci_ptr; / dst counter info */
258	struct gcov_ctr_info sci_ptr; / src counter info */
259	unsigned int active;
260	unsigned int fi_idx; /* function info idx */
261	unsigned int ct_idx; /* counter type idx */
262	size_t fi_size; /* function info size */
263	size_t cv_size; /* counter values size */
264
265	dup = kmemdup(info, sizeof(*dup), GFP_KERNEL);
266	if (!dup)
267	return NULL;
268
269	dup->next = NULL;
270	dup->filename = NULL;
271	dup->functions = NULL;
272
273	dup->filename = kstrdup(info->filename, GFP_KERNEL);
274	if (!dup->filename)
275	goto err_free;
276
277	dup->functions = kcalloc(info->n_functions,
278	sizeof(struct gcov_fn_info *), GFP_KERNEL);
279	if (!dup->functions)
280	goto err_free;
281
282	active = num_counter_active(info);
283	fi_size = sizeof(struct gcov_fn_info);
284	fi_size += sizeof(struct gcov_ctr_info) * active;
285
286	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
287	dup->functions[fi_idx] = kzalloc(fi_size, GFP_KERNEL);
288	if (!dup->functions[fi_idx])
289	goto err_free;
290
291	(dup->functions[fi_idx]) = (info->functions[fi_idx]);
292
293	sci_ptr = info->functions[fi_idx]->ctrs;
294	dci_ptr = dup->functions[fi_idx]->ctrs;
295
296	for (ct_idx = 0; ct_idx < active; ct_idx++) {
297
298	cv_size = sizeof(gcov_type) * sci_ptr->num;
299
300	dci_ptr->values = vmalloc(cv_size);
301
302	if (!dci_ptr->values)
303	goto err_free;
304
305	dci_ptr->num = sci_ptr->num;
306	memcpy(dci_ptr->values, sci_ptr->values, cv_size);
307
308	sci_ptr++;
309	dci_ptr++;
310	}
311	}
312
313	return dup;
314	err_free:
315	gcov_info_free(dup);
316	return NULL;
317	}
318
319	/**
320	* gcov_info_free - release memory for profiling data set duplicate
321	* @info: profiling data set duplicate to free
322	*/
323	void gcov_info_free(struct gcov_info *info)
324	{
325	unsigned int active;
326	unsigned int fi_idx;
327	unsigned int ct_idx;
328	struct gcov_ctr_info *ci_ptr;
329
330	if (!info->functions)
331	goto free_info;
332
333	active = num_counter_active(info);
334
335	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
336	if (!info->functions[fi_idx])
337	continue;
338
339	ci_ptr = info->functions[fi_idx]->ctrs;
340
341	for (ct_idx = 0; ct_idx < active; ct_idx++, ci_ptr++)
342	vfree(ci_ptr->values);
343
344	kfree(info->functions[fi_idx]);
345	}
346
347	free_info:
348	kfree(info->functions);
349	kfree(info->filename);
350	kfree(info);
351	}
352
353	#define ITER_STRIDE PAGE_SIZE
354
355	/**
356	* struct gcov_iterator - specifies current file position in logical records
357	* @info: associated profiling data
358	* @buffer: buffer containing file data
359	* @size: size of buffer
360	* @pos: current position in file
361	*/
362	struct gcov_iterator {
363	struct gcov_info *info;
364	void *buffer;
365	size_t size;
366	loff_t pos;
367	};
368
369	/**
370	* store_gcov_u32 - store 32 bit number in gcov format to buffer
371	* @buffer: target buffer or NULL
372	* @off: offset into the buffer
373	* @v: value to be stored
374	*
375	* Number format defined by gcc: numbers are recorded in the 32 bit
376	* unsigned binary form of the endianness of the machine generating the
377	* file. Returns the number of bytes stored. If @buffer is %NULL, doesn't
378	* store anything.
379	*/
380	static size_t store_gcov_u32(void *buffer, size_t off, u32 v)
381	{
382	u32 *data;
383
384	if (buffer) {
385	data = buffer + off;
386	*data = v;
387	}
388
389	return sizeof(*data);
390	}
391
392	/**
393	* store_gcov_u64 - store 64 bit number in gcov format to buffer
394	* @buffer: target buffer or NULL
395	* @off: offset into the buffer
396	* @v: value to be stored
397	*
398	* Number format defined by gcc: numbers are recorded in the 32 bit
399	* unsigned binary form of the endianness of the machine generating the
400	* file. 64 bit numbers are stored as two 32 bit numbers, the low part
401	* first. Returns the number of bytes stored. If @buffer is %NULL, doesn't store
402	* anything.
403	*/
404	static size_t store_gcov_u64(void *buffer, size_t off, u64 v)
405	{
406	u32 *data;
407
408	if (buffer) {
409	data = buffer + off;
410
411	data[0] = (v & 0xffffffffUL);
412	data[1] = (v >> 32);
413	}
414
415	return sizeof(data) 2;
416	}
417
418	/**
419	* convert_to_gcda - convert profiling data set to gcda file format
420	* @buffer: the buffer to store file data or %NULL if no data should be stored
421	* @info: profiling data set to be converted
422	*
423	* Returns the number of bytes that were/would have been stored into the buffer.
424	*/
425	static size_t convert_to_gcda(char buffer, struct gcov_info info)
426	{
427	struct gcov_fn_info *fi_ptr;
428	struct gcov_ctr_info *ci_ptr;
429	unsigned int fi_idx;
430	unsigned int ct_idx;
431	unsigned int cv_idx;
432	size_t pos = 0;
433
434	/* File header. */
435	pos += store_gcov_u32(buffer, pos, GCOV_DATA_MAGIC);
436	pos += store_gcov_u32(buffer, pos, info->version);
437	pos += store_gcov_u32(buffer, pos, info->stamp);
438
439	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
440	fi_ptr = info->functions[fi_idx];
441
442	/* Function record. */
443	pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION);
444	pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION_LENGTH);
445	pos += store_gcov_u32(buffer, pos, fi_ptr->ident);
446	pos += store_gcov_u32(buffer, pos, fi_ptr->lineno_checksum);
447	pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);
448
449	ci_ptr = fi_ptr->ctrs;
450
451	for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) {
452	if (!counter_active(info, ct_idx))
453	continue;
454
455	/* Counter record. */
456	pos += store_gcov_u32(buffer, pos,
457	GCOV_TAG_FOR_COUNTER(ct_idx));
458	pos += store_gcov_u32(buffer, pos, ci_ptr->num * 2);
459
460	for (cv_idx = 0; cv_idx < ci_ptr->num; cv_idx++) {
461	pos += store_gcov_u64(buffer, pos,
462	ci_ptr->values[cv_idx]);
463	}
464
465	ci_ptr++;
466	}
467	}
468
469	return pos;
470	}
471
472	/**
473	* gcov_iter_new - allocate and initialize profiling data iterator
474	* @info: profiling data set to be iterated
475	*
476	* Return file iterator on success, %NULL otherwise.
477	*/
478	struct gcov_iterator gcov_iter_new(struct gcov_info info)
479	{
480	struct gcov_iterator *iter;
481
482	iter = kzalloc(sizeof(struct gcov_iterator), GFP_KERNEL);
483	if (!iter)
484	goto err_free;
485
486	iter->info = info;
487	/* Dry-run to get the actual buffer size. */
488	iter->size = convert_to_gcda(NULL, info);
489	iter->buffer = vmalloc(iter->size);
490	if (!iter->buffer)
491	goto err_free;
492
493	convert_to_gcda(iter->buffer, info);
494
495	return iter;
496
497	err_free:
498	kfree(iter);
499	return NULL;
500	}
501
502
503	/**
504	* gcov_iter_get_info - return profiling data set for given file iterator
505	* @iter: file iterator
506	*/
507	void gcov_iter_free(struct gcov_iterator *iter)
508	{
509	vfree(iter->buffer);
510	kfree(iter);
511	}
512
513	/**
514	* gcov_iter_get_info - return profiling data set for given file iterator
515	* @iter: file iterator
516	*/
517	struct gcov_info gcov_iter_get_info(struct gcov_iterator iter)
518	{
519	return iter->info;
520	}
521
522	/**
523	* gcov_iter_start - reset file iterator to starting position
524	* @iter: file iterator
525	*/
526	void gcov_iter_start(struct gcov_iterator *iter)
527	{
528	iter->pos = 0;
529	}
530
531	/**
532	* gcov_iter_next - advance file iterator to next logical record
533	* @iter: file iterator
534	*
535	* Return zero if new position is valid, non-zero if iterator has reached end.
536	*/
537	int gcov_iter_next(struct gcov_iterator *iter)
538	{
539	if (iter->pos < iter->size)
540	iter->pos += ITER_STRIDE;
541
542	if (iter->pos >= iter->size)
543	return -EINVAL;
544
545	return 0;
546	}
547
548	/**
549	* gcov_iter_write - write data for current pos to seq_file
550	* @iter: file iterator
551	* @seq: seq_file handle
552	*
553	* Return zero on success, non-zero otherwise.
554	*/
555	int gcov_iter_write(struct gcov_iterator iter, struct seq_file seq)
556	{
557	size_t len;
558
559	if (iter->pos >= iter->size)
560	return -EINVAL;
561
562	len = ITER_STRIDE;
563	if (iter->pos + len > iter->size)
564	len = iter->size - iter->pos;
565
566	seq_write(seq, iter->buffer + iter->pos, len);
567
568	return 0;
569	}