Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/seq_file.c | |
3 | * | |
4 | * helper functions for making synthetic files from sequences of records. | |
5 | * initial implementation -- AV, Oct 2001. | |
6 | */ | |
7 | ||
8 | #include <linux/fs.h> | |
630d9c47 | 9 | #include <linux/export.h> |
1da177e4 LT |
10 | #include <linux/seq_file.h> |
11 | #include <linux/slab.h> | |
adb37c4c | 12 | #include <linux/cred.h> |
1da177e4 LT |
13 | |
14 | #include <asm/uaccess.h> | |
15 | #include <asm/page.h> | |
16 | ||
e075f591 KH |
17 | |
18 | /* | |
19 | * seq_files have a buffer which can may overflow. When this happens a larger | |
20 | * buffer is reallocated and all the data will be printed again. | |
21 | * The overflow state is true when m->count == m->size. | |
22 | */ | |
23 | static bool seq_overflow(struct seq_file *m) | |
24 | { | |
25 | return m->count == m->size; | |
26 | } | |
27 | ||
28 | static void seq_set_overflow(struct seq_file *m) | |
29 | { | |
30 | m->count = m->size; | |
31 | } | |
32 | ||
1da177e4 LT |
33 | /** |
34 | * seq_open - initialize sequential file | |
35 | * @file: file we initialize | |
36 | * @op: method table describing the sequence | |
37 | * | |
38 | * seq_open() sets @file, associating it with a sequence described | |
39 | * by @op. @op->start() sets the iterator up and returns the first | |
40 | * element of sequence. @op->stop() shuts it down. @op->next() | |
41 | * returns the next element of sequence. @op->show() prints element | |
42 | * into the buffer. In case of error ->start() and ->next() return | |
43 | * ERR_PTR(error). In the end of sequence they return %NULL. ->show() | |
44 | * returns 0 in case of success and negative number in case of error. | |
521b5d0c | 45 | * Returning SEQ_SKIP means "discard this element and move on". |
1da177e4 | 46 | */ |
15ad7cdc | 47 | int seq_open(struct file *file, const struct seq_operations *op) |
1da177e4 | 48 | { |
1abe77b0 AV |
49 | struct seq_file *p = file->private_data; |
50 | ||
51 | if (!p) { | |
52 | p = kmalloc(sizeof(*p), GFP_KERNEL); | |
53 | if (!p) | |
54 | return -ENOMEM; | |
55 | file->private_data = p; | |
56 | } | |
1da177e4 | 57 | memset(p, 0, sizeof(*p)); |
0ac1759a | 58 | mutex_init(&p->lock); |
1da177e4 | 59 | p->op = op; |
adb37c4c EB |
60 | #ifdef CONFIG_USER_NS |
61 | p->user_ns = file->f_cred->user_ns; | |
62 | #endif | |
1da177e4 LT |
63 | |
64 | /* | |
65 | * Wrappers around seq_open(e.g. swaps_open) need to be | |
66 | * aware of this. If they set f_version themselves, they | |
67 | * should call seq_open first and then set f_version. | |
68 | */ | |
69 | file->f_version = 0; | |
70 | ||
8f19d472 EB |
71 | /* |
72 | * seq_files support lseek() and pread(). They do not implement | |
73 | * write() at all, but we clear FMODE_PWRITE here for historical | |
74 | * reasons. | |
75 | * | |
76 | * If a client of seq_files a) implements file.write() and b) wishes to | |
77 | * support pwrite() then that client will need to implement its own | |
78 | * file.open() which calls seq_open() and then sets FMODE_PWRITE. | |
79 | */ | |
80 | file->f_mode &= ~FMODE_PWRITE; | |
1da177e4 LT |
81 | return 0; |
82 | } | |
83 | EXPORT_SYMBOL(seq_open); | |
84 | ||
33da8892 EB |
85 | static int traverse(struct seq_file *m, loff_t offset) |
86 | { | |
87 | loff_t pos = 0, index; | |
88 | int error = 0; | |
89 | void *p; | |
90 | ||
91 | m->version = 0; | |
92 | index = 0; | |
93 | m->count = m->from = 0; | |
94 | if (!offset) { | |
95 | m->index = index; | |
96 | return 0; | |
97 | } | |
98 | if (!m->buf) { | |
99 | m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL); | |
100 | if (!m->buf) | |
101 | return -ENOMEM; | |
102 | } | |
103 | p = m->op->start(m, &index); | |
104 | while (p) { | |
105 | error = PTR_ERR(p); | |
106 | if (IS_ERR(p)) | |
107 | break; | |
108 | error = m->op->show(m, p); | |
109 | if (error < 0) | |
110 | break; | |
111 | if (unlikely(error)) { | |
112 | error = 0; | |
113 | m->count = 0; | |
114 | } | |
e075f591 | 115 | if (seq_overflow(m)) |
33da8892 EB |
116 | goto Eoverflow; |
117 | if (pos + m->count > offset) { | |
118 | m->from = offset - pos; | |
119 | m->count -= m->from; | |
120 | m->index = index; | |
121 | break; | |
122 | } | |
123 | pos += m->count; | |
124 | m->count = 0; | |
125 | if (pos == offset) { | |
126 | index++; | |
127 | m->index = index; | |
128 | break; | |
129 | } | |
130 | p = m->op->next(m, p, &index); | |
131 | } | |
132 | m->op->stop(m, p); | |
f01d1d54 | 133 | m->index = index; |
33da8892 EB |
134 | return error; |
135 | ||
136 | Eoverflow: | |
137 | m->op->stop(m, p); | |
138 | kfree(m->buf); | |
801a7605 | 139 | m->count = 0; |
33da8892 EB |
140 | m->buf = kmalloc(m->size <<= 1, GFP_KERNEL); |
141 | return !m->buf ? -ENOMEM : -EAGAIN; | |
142 | } | |
143 | ||
1da177e4 LT |
144 | /** |
145 | * seq_read - ->read() method for sequential files. | |
67be2dd1 MW |
146 | * @file: the file to read from |
147 | * @buf: the buffer to read to | |
148 | * @size: the maximum number of bytes to read | |
149 | * @ppos: the current position in the file | |
1da177e4 LT |
150 | * |
151 | * Ready-made ->f_op->read() | |
152 | */ | |
153 | ssize_t seq_read(struct file *file, char __user *buf, size_t size, loff_t *ppos) | |
154 | { | |
8209e2f4 | 155 | struct seq_file *m = file->private_data; |
1da177e4 LT |
156 | size_t copied = 0; |
157 | loff_t pos; | |
158 | size_t n; | |
159 | void *p; | |
160 | int err = 0; | |
161 | ||
0ac1759a | 162 | mutex_lock(&m->lock); |
8f19d472 | 163 | |
7904ac84 EC |
164 | /* |
165 | * seq_file->op->..m_start/m_stop/m_next may do special actions | |
166 | * or optimisations based on the file->f_version, so we want to | |
167 | * pass the file->f_version to those methods. | |
168 | * | |
169 | * seq_file->version is just copy of f_version, and seq_file | |
170 | * methods can treat it simply as file version. | |
171 | * It is copied in first and copied out after all operations. | |
172 | * It is convenient to have it as part of structure to avoid the | |
173 | * need of passing another argument to all the seq_file methods. | |
174 | */ | |
175 | m->version = file->f_version; | |
176 | ||
8f19d472 EB |
177 | /* Don't assume *ppos is where we left it */ |
178 | if (unlikely(*ppos != m->read_pos)) { | |
8f19d472 EB |
179 | while ((err = traverse(m, *ppos)) == -EAGAIN) |
180 | ; | |
181 | if (err) { | |
182 | /* With prejudice... */ | |
183 | m->read_pos = 0; | |
184 | m->version = 0; | |
185 | m->index = 0; | |
186 | m->count = 0; | |
187 | goto Done; | |
7904ac84 EC |
188 | } else { |
189 | m->read_pos = *ppos; | |
8f19d472 EB |
190 | } |
191 | } | |
192 | ||
1da177e4 LT |
193 | /* grab buffer if we didn't have one */ |
194 | if (!m->buf) { | |
195 | m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL); | |
196 | if (!m->buf) | |
197 | goto Enomem; | |
198 | } | |
199 | /* if not empty - flush it first */ | |
200 | if (m->count) { | |
201 | n = min(m->count, size); | |
202 | err = copy_to_user(buf, m->buf + m->from, n); | |
203 | if (err) | |
204 | goto Efault; | |
205 | m->count -= n; | |
206 | m->from += n; | |
207 | size -= n; | |
208 | buf += n; | |
209 | copied += n; | |
210 | if (!m->count) | |
211 | m->index++; | |
212 | if (!size) | |
213 | goto Done; | |
214 | } | |
215 | /* we need at least one record in buffer */ | |
4cdfe84b AV |
216 | pos = m->index; |
217 | p = m->op->start(m, &pos); | |
1da177e4 | 218 | while (1) { |
1da177e4 LT |
219 | err = PTR_ERR(p); |
220 | if (!p || IS_ERR(p)) | |
221 | break; | |
222 | err = m->op->show(m, p); | |
521b5d0c | 223 | if (err < 0) |
1da177e4 | 224 | break; |
521b5d0c AV |
225 | if (unlikely(err)) |
226 | m->count = 0; | |
4cdfe84b AV |
227 | if (unlikely(!m->count)) { |
228 | p = m->op->next(m, p, &pos); | |
229 | m->index = pos; | |
230 | continue; | |
231 | } | |
1da177e4 LT |
232 | if (m->count < m->size) |
233 | goto Fill; | |
234 | m->op->stop(m, p); | |
235 | kfree(m->buf); | |
801a7605 | 236 | m->count = 0; |
1da177e4 LT |
237 | m->buf = kmalloc(m->size <<= 1, GFP_KERNEL); |
238 | if (!m->buf) | |
239 | goto Enomem; | |
1da177e4 | 240 | m->version = 0; |
4cdfe84b AV |
241 | pos = m->index; |
242 | p = m->op->start(m, &pos); | |
1da177e4 LT |
243 | } |
244 | m->op->stop(m, p); | |
245 | m->count = 0; | |
246 | goto Done; | |
247 | Fill: | |
248 | /* they want more? let's try to get some more */ | |
249 | while (m->count < size) { | |
250 | size_t offs = m->count; | |
251 | loff_t next = pos; | |
252 | p = m->op->next(m, p, &next); | |
253 | if (!p || IS_ERR(p)) { | |
254 | err = PTR_ERR(p); | |
255 | break; | |
256 | } | |
257 | err = m->op->show(m, p); | |
e075f591 | 258 | if (seq_overflow(m) || err) { |
1da177e4 | 259 | m->count = offs; |
521b5d0c AV |
260 | if (likely(err <= 0)) |
261 | break; | |
1da177e4 LT |
262 | } |
263 | pos = next; | |
264 | } | |
265 | m->op->stop(m, p); | |
266 | n = min(m->count, size); | |
267 | err = copy_to_user(buf, m->buf, n); | |
268 | if (err) | |
269 | goto Efault; | |
270 | copied += n; | |
271 | m->count -= n; | |
272 | if (m->count) | |
273 | m->from = n; | |
274 | else | |
275 | pos++; | |
276 | m->index = pos; | |
277 | Done: | |
278 | if (!copied) | |
279 | copied = err; | |
8f19d472 | 280 | else { |
1da177e4 | 281 | *ppos += copied; |
8f19d472 EB |
282 | m->read_pos += copied; |
283 | } | |
1da177e4 | 284 | file->f_version = m->version; |
0ac1759a | 285 | mutex_unlock(&m->lock); |
1da177e4 LT |
286 | return copied; |
287 | Enomem: | |
288 | err = -ENOMEM; | |
289 | goto Done; | |
290 | Efault: | |
291 | err = -EFAULT; | |
292 | goto Done; | |
293 | } | |
294 | EXPORT_SYMBOL(seq_read); | |
295 | ||
1da177e4 LT |
296 | /** |
297 | * seq_lseek - ->llseek() method for sequential files. | |
67be2dd1 MW |
298 | * @file: the file in question |
299 | * @offset: new position | |
254adaa4 | 300 | * @whence: 0 for absolute, 1 for relative position |
1da177e4 LT |
301 | * |
302 | * Ready-made ->f_op->llseek() | |
303 | */ | |
965c8e59 | 304 | loff_t seq_lseek(struct file *file, loff_t offset, int whence) |
1da177e4 | 305 | { |
8209e2f4 | 306 | struct seq_file *m = file->private_data; |
16abef0e | 307 | loff_t retval = -EINVAL; |
1da177e4 | 308 | |
0ac1759a | 309 | mutex_lock(&m->lock); |
1da177e4 | 310 | m->version = file->f_version; |
965c8e59 | 311 | switch (whence) { |
5e62adef AM |
312 | case SEEK_CUR: |
313 | offset += file->f_pos; | |
314 | case SEEK_SET: | |
315 | if (offset < 0) | |
316 | break; | |
317 | retval = offset; | |
318 | if (offset != m->read_pos) { | |
319 | while ((retval = traverse(m, offset)) == -EAGAIN) | |
320 | ; | |
321 | if (retval) { | |
322 | /* with extreme prejudice... */ | |
323 | file->f_pos = 0; | |
324 | m->read_pos = 0; | |
325 | m->version = 0; | |
326 | m->index = 0; | |
327 | m->count = 0; | |
328 | } else { | |
329 | m->read_pos = offset; | |
330 | retval = file->f_pos = offset; | |
1da177e4 | 331 | } |
05e16745 GZ |
332 | } else { |
333 | file->f_pos = offset; | |
5e62adef | 334 | } |
1da177e4 | 335 | } |
1da177e4 | 336 | file->f_version = m->version; |
00c5746d | 337 | mutex_unlock(&m->lock); |
1da177e4 LT |
338 | return retval; |
339 | } | |
340 | EXPORT_SYMBOL(seq_lseek); | |
341 | ||
342 | /** | |
343 | * seq_release - free the structures associated with sequential file. | |
344 | * @file: file in question | |
6131ffaa | 345 | * @inode: its inode |
1da177e4 LT |
346 | * |
347 | * Frees the structures associated with sequential file; can be used | |
348 | * as ->f_op->release() if you don't have private data to destroy. | |
349 | */ | |
350 | int seq_release(struct inode *inode, struct file *file) | |
351 | { | |
8209e2f4 | 352 | struct seq_file *m = file->private_data; |
1da177e4 LT |
353 | kfree(m->buf); |
354 | kfree(m); | |
355 | return 0; | |
356 | } | |
357 | EXPORT_SYMBOL(seq_release); | |
358 | ||
359 | /** | |
360 | * seq_escape - print string into buffer, escaping some characters | |
361 | * @m: target buffer | |
362 | * @s: string | |
363 | * @esc: set of characters that need escaping | |
364 | * | |
365 | * Puts string into buffer, replacing each occurrence of character from | |
366 | * @esc with usual octal escape. Returns 0 in case of success, -1 - in | |
367 | * case of overflow. | |
368 | */ | |
369 | int seq_escape(struct seq_file *m, const char *s, const char *esc) | |
370 | { | |
371 | char *end = m->buf + m->size; | |
372 | char *p; | |
373 | char c; | |
374 | ||
375 | for (p = m->buf + m->count; (c = *s) != '\0' && p < end; s++) { | |
376 | if (!strchr(esc, c)) { | |
377 | *p++ = c; | |
378 | continue; | |
379 | } | |
380 | if (p + 3 < end) { | |
381 | *p++ = '\\'; | |
382 | *p++ = '0' + ((c & 0300) >> 6); | |
383 | *p++ = '0' + ((c & 070) >> 3); | |
384 | *p++ = '0' + (c & 07); | |
385 | continue; | |
386 | } | |
e075f591 | 387 | seq_set_overflow(m); |
1da177e4 LT |
388 | return -1; |
389 | } | |
390 | m->count = p - m->buf; | |
391 | return 0; | |
392 | } | |
393 | EXPORT_SYMBOL(seq_escape); | |
394 | ||
a4808147 | 395 | int seq_vprintf(struct seq_file *m, const char *f, va_list args) |
1da177e4 | 396 | { |
1da177e4 LT |
397 | int len; |
398 | ||
399 | if (m->count < m->size) { | |
1da177e4 | 400 | len = vsnprintf(m->buf + m->count, m->size - m->count, f, args); |
1da177e4 LT |
401 | if (m->count + len < m->size) { |
402 | m->count += len; | |
403 | return 0; | |
404 | } | |
405 | } | |
e075f591 | 406 | seq_set_overflow(m); |
1da177e4 LT |
407 | return -1; |
408 | } | |
a4808147 SW |
409 | EXPORT_SYMBOL(seq_vprintf); |
410 | ||
411 | int seq_printf(struct seq_file *m, const char *f, ...) | |
412 | { | |
413 | int ret; | |
414 | va_list args; | |
415 | ||
416 | va_start(args, f); | |
417 | ret = seq_vprintf(m, f, args); | |
418 | va_end(args); | |
419 | ||
420 | return ret; | |
421 | } | |
1da177e4 LT |
422 | EXPORT_SYMBOL(seq_printf); |
423 | ||
74e2f334 | 424 | /** |
958086d1 TE |
425 | * mangle_path - mangle and copy path to buffer beginning |
426 | * @s: buffer start | |
427 | * @p: beginning of path in above buffer | |
428 | * @esc: set of characters that need escaping | |
74e2f334 TE |
429 | * |
430 | * Copy the path from @p to @s, replacing each occurrence of character from | |
431 | * @esc with usual octal escape. | |
432 | * Returns pointer past last written character in @s, or NULL in case of | |
433 | * failure. | |
434 | */ | |
8c9379e9 | 435 | char *mangle_path(char *s, const char *p, const char *esc) |
6092d048 RP |
436 | { |
437 | while (s <= p) { | |
438 | char c = *p++; | |
439 | if (!c) { | |
440 | return s; | |
441 | } else if (!strchr(esc, c)) { | |
442 | *s++ = c; | |
443 | } else if (s + 4 > p) { | |
444 | break; | |
445 | } else { | |
446 | *s++ = '\\'; | |
447 | *s++ = '0' + ((c & 0300) >> 6); | |
448 | *s++ = '0' + ((c & 070) >> 3); | |
449 | *s++ = '0' + (c & 07); | |
450 | } | |
451 | } | |
452 | return NULL; | |
453 | } | |
604094f4 | 454 | EXPORT_SYMBOL(mangle_path); |
6092d048 | 455 | |
52afeefb AV |
456 | /** |
457 | * seq_path - seq_file interface to print a pathname | |
458 | * @m: the seq_file handle | |
459 | * @path: the struct path to print | |
460 | * @esc: set of characters to escape in the output | |
461 | * | |
462 | * return the absolute path of 'path', as represented by the | |
463 | * dentry / mnt pair in the path parameter. | |
6092d048 | 464 | */ |
8c9379e9 | 465 | int seq_path(struct seq_file *m, const struct path *path, const char *esc) |
1da177e4 | 466 | { |
f8439806 MS |
467 | char *buf; |
468 | size_t size = seq_get_buf(m, &buf); | |
469 | int res = -1; | |
470 | ||
471 | if (size) { | |
472 | char *p = d_path(path, buf, size); | |
1da177e4 | 473 | if (!IS_ERR(p)) { |
f8439806 MS |
474 | char *end = mangle_path(buf, p, esc); |
475 | if (end) | |
476 | res = end - buf; | |
1da177e4 LT |
477 | } |
478 | } | |
f8439806 MS |
479 | seq_commit(m, res); |
480 | ||
481 | return res; | |
1da177e4 LT |
482 | } |
483 | EXPORT_SYMBOL(seq_path); | |
484 | ||
9d1bc601 MS |
485 | /* |
486 | * Same as seq_path, but relative to supplied root. | |
9d1bc601 | 487 | */ |
8c9379e9 AV |
488 | int seq_path_root(struct seq_file *m, const struct path *path, |
489 | const struct path *root, const char *esc) | |
9d1bc601 | 490 | { |
f8439806 MS |
491 | char *buf; |
492 | size_t size = seq_get_buf(m, &buf); | |
493 | int res = -ENAMETOOLONG; | |
494 | ||
495 | if (size) { | |
9d1bc601 MS |
496 | char *p; |
497 | ||
f8439806 | 498 | p = __d_path(path, root, buf, size); |
02125a82 AV |
499 | if (!p) |
500 | return SEQ_SKIP; | |
f8439806 | 501 | res = PTR_ERR(p); |
9d1bc601 | 502 | if (!IS_ERR(p)) { |
f8439806 MS |
503 | char *end = mangle_path(buf, p, esc); |
504 | if (end) | |
505 | res = end - buf; | |
506 | else | |
507 | res = -ENAMETOOLONG; | |
9d1bc601 MS |
508 | } |
509 | } | |
f8439806 MS |
510 | seq_commit(m, res); |
511 | ||
02125a82 | 512 | return res < 0 && res != -ENAMETOOLONG ? res : 0; |
9d1bc601 MS |
513 | } |
514 | ||
6092d048 RP |
515 | /* |
516 | * returns the path of the 'dentry' from the root of its filesystem. | |
517 | */ | |
8c9379e9 | 518 | int seq_dentry(struct seq_file *m, struct dentry *dentry, const char *esc) |
6092d048 | 519 | { |
f8439806 MS |
520 | char *buf; |
521 | size_t size = seq_get_buf(m, &buf); | |
522 | int res = -1; | |
523 | ||
524 | if (size) { | |
525 | char *p = dentry_path(dentry, buf, size); | |
6092d048 | 526 | if (!IS_ERR(p)) { |
f8439806 MS |
527 | char *end = mangle_path(buf, p, esc); |
528 | if (end) | |
529 | res = end - buf; | |
6092d048 RP |
530 | } |
531 | } | |
f8439806 MS |
532 | seq_commit(m, res); |
533 | ||
534 | return res; | |
6092d048 RP |
535 | } |
536 | ||
cb78a0ce RR |
537 | int seq_bitmap(struct seq_file *m, const unsigned long *bits, |
538 | unsigned int nr_bits) | |
50ac2d69 | 539 | { |
85dd030e LJ |
540 | if (m->count < m->size) { |
541 | int len = bitmap_scnprintf(m->buf + m->count, | |
542 | m->size - m->count, bits, nr_bits); | |
543 | if (m->count + len < m->size) { | |
544 | m->count += len; | |
545 | return 0; | |
546 | } | |
50ac2d69 | 547 | } |
e075f591 | 548 | seq_set_overflow(m); |
50ac2d69 AD |
549 | return -1; |
550 | } | |
85dd030e | 551 | EXPORT_SYMBOL(seq_bitmap); |
50ac2d69 | 552 | |
af76aba0 | 553 | int seq_bitmap_list(struct seq_file *m, const unsigned long *bits, |
3eda2011 LJ |
554 | unsigned int nr_bits) |
555 | { | |
556 | if (m->count < m->size) { | |
557 | int len = bitmap_scnlistprintf(m->buf + m->count, | |
558 | m->size - m->count, bits, nr_bits); | |
559 | if (m->count + len < m->size) { | |
560 | m->count += len; | |
561 | return 0; | |
562 | } | |
563 | } | |
e075f591 | 564 | seq_set_overflow(m); |
3eda2011 LJ |
565 | return -1; |
566 | } | |
567 | EXPORT_SYMBOL(seq_bitmap_list); | |
568 | ||
1da177e4 LT |
569 | static void *single_start(struct seq_file *p, loff_t *pos) |
570 | { | |
571 | return NULL + (*pos == 0); | |
572 | } | |
573 | ||
574 | static void *single_next(struct seq_file *p, void *v, loff_t *pos) | |
575 | { | |
576 | ++*pos; | |
577 | return NULL; | |
578 | } | |
579 | ||
580 | static void single_stop(struct seq_file *p, void *v) | |
581 | { | |
582 | } | |
583 | ||
584 | int single_open(struct file *file, int (*show)(struct seq_file *, void *), | |
585 | void *data) | |
586 | { | |
587 | struct seq_operations *op = kmalloc(sizeof(*op), GFP_KERNEL); | |
588 | int res = -ENOMEM; | |
589 | ||
590 | if (op) { | |
591 | op->start = single_start; | |
592 | op->next = single_next; | |
593 | op->stop = single_stop; | |
594 | op->show = show; | |
595 | res = seq_open(file, op); | |
596 | if (!res) | |
597 | ((struct seq_file *)file->private_data)->private = data; | |
598 | else | |
599 | kfree(op); | |
600 | } | |
601 | return res; | |
602 | } | |
603 | EXPORT_SYMBOL(single_open); | |
604 | ||
2043f495 AV |
605 | int single_open_size(struct file *file, int (*show)(struct seq_file *, void *), |
606 | void *data, size_t size) | |
607 | { | |
608 | char *buf = kmalloc(size, GFP_KERNEL); | |
609 | int ret; | |
610 | if (!buf) | |
611 | return -ENOMEM; | |
612 | ret = single_open(file, show, data); | |
613 | if (ret) { | |
614 | kfree(buf); | |
615 | return ret; | |
616 | } | |
617 | ((struct seq_file *)file->private_data)->buf = buf; | |
618 | ((struct seq_file *)file->private_data)->size = size; | |
619 | return 0; | |
620 | } | |
621 | EXPORT_SYMBOL(single_open_size); | |
622 | ||
1da177e4 LT |
623 | int single_release(struct inode *inode, struct file *file) |
624 | { | |
15ad7cdc | 625 | const struct seq_operations *op = ((struct seq_file *)file->private_data)->op; |
1da177e4 LT |
626 | int res = seq_release(inode, file); |
627 | kfree(op); | |
628 | return res; | |
629 | } | |
630 | EXPORT_SYMBOL(single_release); | |
631 | ||
632 | int seq_release_private(struct inode *inode, struct file *file) | |
633 | { | |
634 | struct seq_file *seq = file->private_data; | |
635 | ||
636 | kfree(seq->private); | |
637 | seq->private = NULL; | |
638 | return seq_release(inode, file); | |
639 | } | |
640 | EXPORT_SYMBOL(seq_release_private); | |
641 | ||
39699037 PE |
642 | void *__seq_open_private(struct file *f, const struct seq_operations *ops, |
643 | int psize) | |
644 | { | |
645 | int rc; | |
646 | void *private; | |
647 | struct seq_file *seq; | |
648 | ||
649 | private = kzalloc(psize, GFP_KERNEL); | |
650 | if (private == NULL) | |
651 | goto out; | |
652 | ||
653 | rc = seq_open(f, ops); | |
654 | if (rc < 0) | |
655 | goto out_free; | |
656 | ||
657 | seq = f->private_data; | |
658 | seq->private = private; | |
659 | return private; | |
660 | ||
661 | out_free: | |
662 | kfree(private); | |
663 | out: | |
664 | return NULL; | |
665 | } | |
666 | EXPORT_SYMBOL(__seq_open_private); | |
667 | ||
668 | int seq_open_private(struct file *filp, const struct seq_operations *ops, | |
669 | int psize) | |
670 | { | |
671 | return __seq_open_private(filp, ops, psize) ? 0 : -ENOMEM; | |
672 | } | |
673 | EXPORT_SYMBOL(seq_open_private); | |
674 | ||
1da177e4 LT |
675 | int seq_putc(struct seq_file *m, char c) |
676 | { | |
677 | if (m->count < m->size) { | |
678 | m->buf[m->count++] = c; | |
679 | return 0; | |
680 | } | |
681 | return -1; | |
682 | } | |
683 | EXPORT_SYMBOL(seq_putc); | |
684 | ||
685 | int seq_puts(struct seq_file *m, const char *s) | |
686 | { | |
687 | int len = strlen(s); | |
688 | if (m->count + len < m->size) { | |
689 | memcpy(m->buf + m->count, s, len); | |
690 | m->count += len; | |
691 | return 0; | |
692 | } | |
e075f591 | 693 | seq_set_overflow(m); |
1da177e4 LT |
694 | return -1; |
695 | } | |
696 | EXPORT_SYMBOL(seq_puts); | |
bcf67e16 | 697 | |
1ac101a5 KH |
698 | /* |
699 | * A helper routine for putting decimal numbers without rich format of printf(). | |
700 | * only 'unsigned long long' is supported. | |
701 | * This routine will put one byte delimiter + number into seq_file. | |
702 | * This routine is very quick when you show lots of numbers. | |
703 | * In usual cases, it will be better to use seq_printf(). It's easier to read. | |
704 | */ | |
705 | int seq_put_decimal_ull(struct seq_file *m, char delimiter, | |
706 | unsigned long long num) | |
707 | { | |
708 | int len; | |
709 | ||
710 | if (m->count + 2 >= m->size) /* we'll write 2 bytes at least */ | |
711 | goto overflow; | |
712 | ||
bda7bad6 KH |
713 | if (delimiter) |
714 | m->buf[m->count++] = delimiter; | |
1ac101a5 KH |
715 | |
716 | if (num < 10) { | |
717 | m->buf[m->count++] = num + '0'; | |
718 | return 0; | |
719 | } | |
720 | ||
721 | len = num_to_str(m->buf + m->count, m->size - m->count, num); | |
722 | if (!len) | |
723 | goto overflow; | |
724 | m->count += len; | |
725 | return 0; | |
726 | overflow: | |
e075f591 | 727 | seq_set_overflow(m); |
1ac101a5 KH |
728 | return -1; |
729 | } | |
730 | EXPORT_SYMBOL(seq_put_decimal_ull); | |
731 | ||
bda7bad6 KH |
732 | int seq_put_decimal_ll(struct seq_file *m, char delimiter, |
733 | long long num) | |
734 | { | |
735 | if (num < 0) { | |
736 | if (m->count + 3 >= m->size) { | |
e075f591 | 737 | seq_set_overflow(m); |
bda7bad6 KH |
738 | return -1; |
739 | } | |
740 | if (delimiter) | |
741 | m->buf[m->count++] = delimiter; | |
742 | num = -num; | |
743 | delimiter = '-'; | |
744 | } | |
745 | return seq_put_decimal_ull(m, delimiter, num); | |
746 | ||
747 | } | |
748 | EXPORT_SYMBOL(seq_put_decimal_ll); | |
749 | ||
0b923606 PO |
750 | /** |
751 | * seq_write - write arbitrary data to buffer | |
752 | * @seq: seq_file identifying the buffer to which data should be written | |
753 | * @data: data address | |
754 | * @len: number of bytes | |
755 | * | |
756 | * Return 0 on success, non-zero otherwise. | |
757 | */ | |
758 | int seq_write(struct seq_file *seq, const void *data, size_t len) | |
759 | { | |
760 | if (seq->count + len < seq->size) { | |
761 | memcpy(seq->buf + seq->count, data, len); | |
762 | seq->count += len; | |
763 | return 0; | |
764 | } | |
e075f591 | 765 | seq_set_overflow(seq); |
0b923606 PO |
766 | return -1; |
767 | } | |
768 | EXPORT_SYMBOL(seq_write); | |
769 | ||
839cc2a9 TH |
770 | /** |
771 | * seq_pad - write padding spaces to buffer | |
772 | * @m: seq_file identifying the buffer to which data should be written | |
773 | * @c: the byte to append after padding if non-zero | |
774 | */ | |
775 | void seq_pad(struct seq_file *m, char c) | |
776 | { | |
777 | int size = m->pad_until - m->count; | |
778 | if (size > 0) | |
779 | seq_printf(m, "%*s", size, ""); | |
780 | if (c) | |
781 | seq_putc(m, c); | |
782 | } | |
783 | EXPORT_SYMBOL(seq_pad); | |
784 | ||
bcf67e16 PE |
785 | struct list_head *seq_list_start(struct list_head *head, loff_t pos) |
786 | { | |
787 | struct list_head *lh; | |
788 | ||
789 | list_for_each(lh, head) | |
790 | if (pos-- == 0) | |
791 | return lh; | |
792 | ||
793 | return NULL; | |
794 | } | |
bcf67e16 PE |
795 | EXPORT_SYMBOL(seq_list_start); |
796 | ||
797 | struct list_head *seq_list_start_head(struct list_head *head, loff_t pos) | |
798 | { | |
799 | if (!pos) | |
800 | return head; | |
801 | ||
802 | return seq_list_start(head, pos - 1); | |
803 | } | |
bcf67e16 PE |
804 | EXPORT_SYMBOL(seq_list_start_head); |
805 | ||
806 | struct list_head *seq_list_next(void *v, struct list_head *head, loff_t *ppos) | |
807 | { | |
808 | struct list_head *lh; | |
809 | ||
810 | lh = ((struct list_head *)v)->next; | |
811 | ++*ppos; | |
812 | return lh == head ? NULL : lh; | |
813 | } | |
bcf67e16 | 814 | EXPORT_SYMBOL(seq_list_next); |
66655de6 LZ |
815 | |
816 | /** | |
817 | * seq_hlist_start - start an iteration of a hlist | |
818 | * @head: the head of the hlist | |
819 | * @pos: the start position of the sequence | |
820 | * | |
821 | * Called at seq_file->op->start(). | |
822 | */ | |
823 | struct hlist_node *seq_hlist_start(struct hlist_head *head, loff_t pos) | |
824 | { | |
825 | struct hlist_node *node; | |
826 | ||
827 | hlist_for_each(node, head) | |
828 | if (pos-- == 0) | |
829 | return node; | |
830 | return NULL; | |
831 | } | |
832 | EXPORT_SYMBOL(seq_hlist_start); | |
833 | ||
834 | /** | |
835 | * seq_hlist_start_head - start an iteration of a hlist | |
836 | * @head: the head of the hlist | |
837 | * @pos: the start position of the sequence | |
838 | * | |
839 | * Called at seq_file->op->start(). Call this function if you want to | |
840 | * print a header at the top of the output. | |
841 | */ | |
842 | struct hlist_node *seq_hlist_start_head(struct hlist_head *head, loff_t pos) | |
843 | { | |
844 | if (!pos) | |
845 | return SEQ_START_TOKEN; | |
846 | ||
847 | return seq_hlist_start(head, pos - 1); | |
848 | } | |
849 | EXPORT_SYMBOL(seq_hlist_start_head); | |
850 | ||
851 | /** | |
852 | * seq_hlist_next - move to the next position of the hlist | |
853 | * @v: the current iterator | |
854 | * @head: the head of the hlist | |
138860b9 | 855 | * @ppos: the current position |
66655de6 LZ |
856 | * |
857 | * Called at seq_file->op->next(). | |
858 | */ | |
859 | struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head, | |
860 | loff_t *ppos) | |
861 | { | |
862 | struct hlist_node *node = v; | |
863 | ||
864 | ++*ppos; | |
865 | if (v == SEQ_START_TOKEN) | |
866 | return head->first; | |
867 | else | |
868 | return node->next; | |
869 | } | |
870 | EXPORT_SYMBOL(seq_hlist_next); | |
1cc52327 | 871 | |
872 | /** | |
873 | * seq_hlist_start_rcu - start an iteration of a hlist protected by RCU | |
874 | * @head: the head of the hlist | |
875 | * @pos: the start position of the sequence | |
876 | * | |
877 | * Called at seq_file->op->start(). | |
878 | * | |
879 | * This list-traversal primitive may safely run concurrently with | |
880 | * the _rcu list-mutation primitives such as hlist_add_head_rcu() | |
881 | * as long as the traversal is guarded by rcu_read_lock(). | |
882 | */ | |
883 | struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head, | |
884 | loff_t pos) | |
885 | { | |
886 | struct hlist_node *node; | |
887 | ||
888 | __hlist_for_each_rcu(node, head) | |
889 | if (pos-- == 0) | |
890 | return node; | |
891 | return NULL; | |
892 | } | |
893 | EXPORT_SYMBOL(seq_hlist_start_rcu); | |
894 | ||
895 | /** | |
896 | * seq_hlist_start_head_rcu - start an iteration of a hlist protected by RCU | |
897 | * @head: the head of the hlist | |
898 | * @pos: the start position of the sequence | |
899 | * | |
900 | * Called at seq_file->op->start(). Call this function if you want to | |
901 | * print a header at the top of the output. | |
902 | * | |
903 | * This list-traversal primitive may safely run concurrently with | |
904 | * the _rcu list-mutation primitives such as hlist_add_head_rcu() | |
905 | * as long as the traversal is guarded by rcu_read_lock(). | |
906 | */ | |
907 | struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head, | |
908 | loff_t pos) | |
909 | { | |
910 | if (!pos) | |
911 | return SEQ_START_TOKEN; | |
912 | ||
913 | return seq_hlist_start_rcu(head, pos - 1); | |
914 | } | |
915 | EXPORT_SYMBOL(seq_hlist_start_head_rcu); | |
916 | ||
917 | /** | |
918 | * seq_hlist_next_rcu - move to the next position of the hlist protected by RCU | |
919 | * @v: the current iterator | |
920 | * @head: the head of the hlist | |
138860b9 | 921 | * @ppos: the current position |
1cc52327 | 922 | * |
923 | * Called at seq_file->op->next(). | |
924 | * | |
925 | * This list-traversal primitive may safely run concurrently with | |
926 | * the _rcu list-mutation primitives such as hlist_add_head_rcu() | |
927 | * as long as the traversal is guarded by rcu_read_lock(). | |
928 | */ | |
929 | struct hlist_node *seq_hlist_next_rcu(void *v, | |
930 | struct hlist_head *head, | |
931 | loff_t *ppos) | |
932 | { | |
933 | struct hlist_node *node = v; | |
934 | ||
935 | ++*ppos; | |
936 | if (v == SEQ_START_TOKEN) | |
937 | return rcu_dereference(head->first); | |
938 | else | |
939 | return rcu_dereference(node->next); | |
940 | } | |
941 | EXPORT_SYMBOL(seq_hlist_next_rcu); | |
0bc77381 JL |
942 | |
943 | /** | |
944 | * seq_hlist_start_precpu - start an iteration of a percpu hlist array | |
945 | * @head: pointer to percpu array of struct hlist_heads | |
946 | * @cpu: pointer to cpu "cursor" | |
947 | * @pos: start position of sequence | |
948 | * | |
949 | * Called at seq_file->op->start(). | |
950 | */ | |
951 | struct hlist_node * | |
952 | seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos) | |
953 | { | |
954 | struct hlist_node *node; | |
955 | ||
956 | for_each_possible_cpu(*cpu) { | |
957 | hlist_for_each(node, per_cpu_ptr(head, *cpu)) { | |
958 | if (pos-- == 0) | |
959 | return node; | |
960 | } | |
961 | } | |
962 | return NULL; | |
963 | } | |
964 | EXPORT_SYMBOL(seq_hlist_start_percpu); | |
965 | ||
966 | /** | |
967 | * seq_hlist_next_percpu - move to the next position of the percpu hlist array | |
968 | * @v: pointer to current hlist_node | |
969 | * @head: pointer to percpu array of struct hlist_heads | |
970 | * @cpu: pointer to cpu "cursor" | |
971 | * @pos: start position of sequence | |
972 | * | |
973 | * Called at seq_file->op->next(). | |
974 | */ | |
975 | struct hlist_node * | |
976 | seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, | |
977 | int *cpu, loff_t *pos) | |
978 | { | |
979 | struct hlist_node *node = v; | |
980 | ||
981 | ++*pos; | |
982 | ||
983 | if (node->next) | |
984 | return node->next; | |
985 | ||
986 | for (*cpu = cpumask_next(*cpu, cpu_possible_mask); *cpu < nr_cpu_ids; | |
987 | *cpu = cpumask_next(*cpu, cpu_possible_mask)) { | |
988 | struct hlist_head *bucket = per_cpu_ptr(head, *cpu); | |
989 | ||
990 | if (!hlist_empty(bucket)) | |
991 | return bucket->first; | |
992 | } | |
993 | return NULL; | |
994 | } | |
995 | EXPORT_SYMBOL(seq_hlist_next_percpu); |