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9#include <linux/cache.h>
10#include <linux/fs.h>
11#include <linux/export.h>
12#include <linux/seq_file.h>
13#include <linux/vmalloc.h>
14#include <linux/slab.h>
15#include <linux/cred.h>
16#include <linux/mm.h>
17#include <linux/printk.h>
18#include <linux/string_helpers.h>
19
20#include <linux/uaccess.h>
21#include <asm/page.h>
22
23static struct kmem_cache *seq_file_cache __ro_after_init;
24
25static void seq_set_overflow(struct seq_file *m)
26{
27 m->count = m->size;
28}
29
30static void *seq_buf_alloc(unsigned long size)
31{
32 return kvmalloc(size, GFP_KERNEL_ACCOUNT);
33}
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51int seq_open(struct file *file, const struct seq_operations *op)
52{
53 struct seq_file *p;
54
55 WARN_ON(file->private_data);
56
57 p = kmem_cache_zalloc(seq_file_cache, GFP_KERNEL);
58 if (!p)
59 return -ENOMEM;
60
61 file->private_data = p;
62
63 mutex_init(&p->lock);
64 p->op = op;
65
66
67
68 p->file = file;
69
70
71
72
73
74
75 file->f_version = 0;
76
77
78
79
80
81
82
83
84
85
86 file->f_mode &= ~FMODE_PWRITE;
87 return 0;
88}
89EXPORT_SYMBOL(seq_open);
90
91static int traverse(struct seq_file *m, loff_t offset)
92{
93 loff_t pos = 0;
94 int error = 0;
95 void *p;
96
97 m->version = 0;
98 m->index = 0;
99 m->count = m->from = 0;
100 if (!offset)
101 return 0;
102
103 if (!m->buf) {
104 m->buf = seq_buf_alloc(m->size = PAGE_SIZE);
105 if (!m->buf)
106 return -ENOMEM;
107 }
108 p = m->op->start(m, &m->index);
109 while (p) {
110 error = PTR_ERR(p);
111 if (IS_ERR(p))
112 break;
113 error = m->op->show(m, p);
114 if (error < 0)
115 break;
116 if (unlikely(error)) {
117 error = 0;
118 m->count = 0;
119 }
120 if (seq_has_overflowed(m))
121 goto Eoverflow;
122 p = m->op->next(m, p, &m->index);
123 if (pos + m->count > offset) {
124 m->from = offset - pos;
125 m->count -= m->from;
126 break;
127 }
128 pos += m->count;
129 m->count = 0;
130 if (pos == offset)
131 break;
132 }
133 m->op->stop(m, p);
134 return error;
135
136Eoverflow:
137 m->op->stop(m, p);
138 kvfree(m->buf);
139 m->count = 0;
140 m->buf = seq_buf_alloc(m->size <<= 1);
141 return !m->buf ? -ENOMEM : -EAGAIN;
142}
143
144
145
146
147
148
149
150
151
152
153ssize_t seq_read(struct file *file, char __user *buf, size_t size, loff_t *ppos)
154{
155 struct seq_file *m = file->private_data;
156 size_t copied = 0;
157 size_t n;
158 void *p;
159 int err = 0;
160
161 mutex_lock(&m->lock);
162
163
164
165
166
167
168
169
170
171
172
173
174 m->version = file->f_version;
175
176
177
178
179
180 if (*ppos == 0) {
181 m->index = 0;
182 m->version = 0;
183 m->count = 0;
184 }
185
186
187 if (unlikely(*ppos != m->read_pos)) {
188 while ((err = traverse(m, *ppos)) == -EAGAIN)
189 ;
190 if (err) {
191
192 m->read_pos = 0;
193 m->version = 0;
194 m->index = 0;
195 m->count = 0;
196 goto Done;
197 } else {
198 m->read_pos = *ppos;
199 }
200 }
201
202
203 if (!m->buf) {
204 m->buf = seq_buf_alloc(m->size = PAGE_SIZE);
205 if (!m->buf)
206 goto Enomem;
207 }
208
209 if (m->count) {
210 n = min(m->count, size);
211 err = copy_to_user(buf, m->buf + m->from, n);
212 if (err)
213 goto Efault;
214 m->count -= n;
215 m->from += n;
216 size -= n;
217 buf += n;
218 copied += n;
219 if (!size)
220 goto Done;
221 }
222
223 m->from = 0;
224 p = m->op->start(m, &m->index);
225 while (1) {
226 err = PTR_ERR(p);
227 if (!p || IS_ERR(p))
228 break;
229 err = m->op->show(m, p);
230 if (err < 0)
231 break;
232 if (unlikely(err))
233 m->count = 0;
234 if (unlikely(!m->count)) {
235 p = m->op->next(m, p, &m->index);
236 continue;
237 }
238 if (m->count < m->size)
239 goto Fill;
240 m->op->stop(m, p);
241 kvfree(m->buf);
242 m->count = 0;
243 m->buf = seq_buf_alloc(m->size <<= 1);
244 if (!m->buf)
245 goto Enomem;
246 m->version = 0;
247 p = m->op->start(m, &m->index);
248 }
249 m->op->stop(m, p);
250 m->count = 0;
251 goto Done;
252Fill:
253
254 while (1) {
255 size_t offs = m->count;
256 loff_t pos = m->index;
257
258 p = m->op->next(m, p, &m->index);
259 if (pos == m->index)
260
261 m->index++;
262 if (!p || IS_ERR(p)) {
263 err = PTR_ERR(p);
264 break;
265 }
266 if (m->count >= size)
267 break;
268 err = m->op->show(m, p);
269 if (seq_has_overflowed(m) || err) {
270 m->count = offs;
271 if (likely(err <= 0))
272 break;
273 }
274 }
275 m->op->stop(m, p);
276 n = min(m->count, size);
277 err = copy_to_user(buf, m->buf, n);
278 if (err)
279 goto Efault;
280 copied += n;
281 m->count -= n;
282 m->from = n;
283Done:
284 if (!copied)
285 copied = err;
286 else {
287 *ppos += copied;
288 m->read_pos += copied;
289 }
290 file->f_version = m->version;
291 mutex_unlock(&m->lock);
292 return copied;
293Enomem:
294 err = -ENOMEM;
295 goto Done;
296Efault:
297 err = -EFAULT;
298 goto Done;
299}
300EXPORT_SYMBOL(seq_read);
301
302
303
304
305
306
307
308
309
310loff_t seq_lseek(struct file *file, loff_t offset, int whence)
311{
312 struct seq_file *m = file->private_data;
313 loff_t retval = -EINVAL;
314
315 mutex_lock(&m->lock);
316 m->version = file->f_version;
317 switch (whence) {
318 case SEEK_CUR:
319 offset += file->f_pos;
320
321 case SEEK_SET:
322 if (offset < 0)
323 break;
324 retval = offset;
325 if (offset != m->read_pos) {
326 while ((retval = traverse(m, offset)) == -EAGAIN)
327 ;
328 if (retval) {
329
330 file->f_pos = 0;
331 m->read_pos = 0;
332 m->version = 0;
333 m->index = 0;
334 m->count = 0;
335 } else {
336 m->read_pos = offset;
337 retval = file->f_pos = offset;
338 }
339 } else {
340 file->f_pos = offset;
341 }
342 }
343 file->f_version = m->version;
344 mutex_unlock(&m->lock);
345 return retval;
346}
347EXPORT_SYMBOL(seq_lseek);
348
349
350
351
352
353
354
355
356
357int seq_release(struct inode *inode, struct file *file)
358{
359 struct seq_file *m = file->private_data;
360 kvfree(m->buf);
361 kmem_cache_free(seq_file_cache, m);
362 return 0;
363}
364EXPORT_SYMBOL(seq_release);
365
366
367
368
369
370
371
372
373
374
375
376void seq_escape(struct seq_file *m, const char *s, const char *esc)
377{
378 char *buf;
379 size_t size = seq_get_buf(m, &buf);
380 int ret;
381
382 ret = string_escape_str(s, buf, size, ESCAPE_OCTAL, esc);
383 seq_commit(m, ret < size ? ret : -1);
384}
385EXPORT_SYMBOL(seq_escape);
386
387void seq_escape_mem_ascii(struct seq_file *m, const char *src, size_t isz)
388{
389 char *buf;
390 size_t size = seq_get_buf(m, &buf);
391 int ret;
392
393 ret = string_escape_mem_ascii(src, isz, buf, size);
394 seq_commit(m, ret < size ? ret : -1);
395}
396EXPORT_SYMBOL(seq_escape_mem_ascii);
397
398void seq_vprintf(struct seq_file *m, const char *f, va_list args)
399{
400 int len;
401
402 if (m->count < m->size) {
403 len = vsnprintf(m->buf + m->count, m->size - m->count, f, args);
404 if (m->count + len < m->size) {
405 m->count += len;
406 return;
407 }
408 }
409 seq_set_overflow(m);
410}
411EXPORT_SYMBOL(seq_vprintf);
412
413void seq_printf(struct seq_file *m, const char *f, ...)
414{
415 va_list args;
416
417 va_start(args, f);
418 seq_vprintf(m, f, args);
419 va_end(args);
420}
421EXPORT_SYMBOL(seq_printf);
422
423
424
425
426
427
428
429
430
431
432
433
434char *mangle_path(char *s, const char *p, const char *esc)
435{
436 while (s <= p) {
437 char c = *p++;
438 if (!c) {
439 return s;
440 } else if (!strchr(esc, c)) {
441 *s++ = c;
442 } else if (s + 4 > p) {
443 break;
444 } else {
445 *s++ = '\\';
446 *s++ = '0' + ((c & 0300) >> 6);
447 *s++ = '0' + ((c & 070) >> 3);
448 *s++ = '0' + (c & 07);
449 }
450 }
451 return NULL;
452}
453EXPORT_SYMBOL(mangle_path);
454
455
456
457
458
459
460
461
462
463
464int seq_path(struct seq_file *m, const struct path *path, const char *esc)
465{
466 char *buf;
467 size_t size = seq_get_buf(m, &buf);
468 int res = -1;
469
470 if (size) {
471 char *p = d_path(path, buf, size);
472 if (!IS_ERR(p)) {
473 char *end = mangle_path(buf, p, esc);
474 if (end)
475 res = end - buf;
476 }
477 }
478 seq_commit(m, res);
479
480 return res;
481}
482EXPORT_SYMBOL(seq_path);
483
484
485
486
487
488
489
490
491
492int seq_file_path(struct seq_file *m, struct file *file, const char *esc)
493{
494 return seq_path(m, &file->f_path, esc);
495}
496EXPORT_SYMBOL(seq_file_path);
497
498
499
500
501int seq_path_root(struct seq_file *m, const struct path *path,
502 const struct path *root, const char *esc)
503{
504 char *buf;
505 size_t size = seq_get_buf(m, &buf);
506 int res = -ENAMETOOLONG;
507
508 if (size) {
509 char *p;
510
511 p = __d_path(path, root, buf, size);
512 if (!p)
513 return SEQ_SKIP;
514 res = PTR_ERR(p);
515 if (!IS_ERR(p)) {
516 char *end = mangle_path(buf, p, esc);
517 if (end)
518 res = end - buf;
519 else
520 res = -ENAMETOOLONG;
521 }
522 }
523 seq_commit(m, res);
524
525 return res < 0 && res != -ENAMETOOLONG ? res : 0;
526}
527
528
529
530
531int seq_dentry(struct seq_file *m, struct dentry *dentry, const char *esc)
532{
533 char *buf;
534 size_t size = seq_get_buf(m, &buf);
535 int res = -1;
536
537 if (size) {
538 char *p = dentry_path(dentry, buf, size);
539 if (!IS_ERR(p)) {
540 char *end = mangle_path(buf, p, esc);
541 if (end)
542 res = end - buf;
543 }
544 }
545 seq_commit(m, res);
546
547 return res;
548}
549EXPORT_SYMBOL(seq_dentry);
550
551static void *single_start(struct seq_file *p, loff_t *pos)
552{
553 return NULL + (*pos == 0);
554}
555
556static void *single_next(struct seq_file *p, void *v, loff_t *pos)
557{
558 ++*pos;
559 return NULL;
560}
561
562static void single_stop(struct seq_file *p, void *v)
563{
564}
565
566int single_open(struct file *file, int (*show)(struct seq_file *, void *),
567 void *data)
568{
569 struct seq_operations *op = kmalloc(sizeof(*op), GFP_KERNEL_ACCOUNT);
570 int res = -ENOMEM;
571
572 if (op) {
573 op->start = single_start;
574 op->next = single_next;
575 op->stop = single_stop;
576 op->show = show;
577 res = seq_open(file, op);
578 if (!res)
579 ((struct seq_file *)file->private_data)->private = data;
580 else
581 kfree(op);
582 }
583 return res;
584}
585EXPORT_SYMBOL(single_open);
586
587int single_open_size(struct file *file, int (*show)(struct seq_file *, void *),
588 void *data, size_t size)
589{
590 char *buf = seq_buf_alloc(size);
591 int ret;
592 if (!buf)
593 return -ENOMEM;
594 ret = single_open(file, show, data);
595 if (ret) {
596 kvfree(buf);
597 return ret;
598 }
599 ((struct seq_file *)file->private_data)->buf = buf;
600 ((struct seq_file *)file->private_data)->size = size;
601 return 0;
602}
603EXPORT_SYMBOL(single_open_size);
604
605int single_release(struct inode *inode, struct file *file)
606{
607 const struct seq_operations *op = ((struct seq_file *)file->private_data)->op;
608 int res = seq_release(inode, file);
609 kfree(op);
610 return res;
611}
612EXPORT_SYMBOL(single_release);
613
614int seq_release_private(struct inode *inode, struct file *file)
615{
616 struct seq_file *seq = file->private_data;
617
618 kfree(seq->private);
619 seq->private = NULL;
620 return seq_release(inode, file);
621}
622EXPORT_SYMBOL(seq_release_private);
623
624void *__seq_open_private(struct file *f, const struct seq_operations *ops,
625 int psize)
626{
627 int rc;
628 void *private;
629 struct seq_file *seq;
630
631 private = kzalloc(psize, GFP_KERNEL_ACCOUNT);
632 if (private == NULL)
633 goto out;
634
635 rc = seq_open(f, ops);
636 if (rc < 0)
637 goto out_free;
638
639 seq = f->private_data;
640 seq->private = private;
641 return private;
642
643out_free:
644 kfree(private);
645out:
646 return NULL;
647}
648EXPORT_SYMBOL(__seq_open_private);
649
650int seq_open_private(struct file *filp, const struct seq_operations *ops,
651 int psize)
652{
653 return __seq_open_private(filp, ops, psize) ? 0 : -ENOMEM;
654}
655EXPORT_SYMBOL(seq_open_private);
656
657void seq_putc(struct seq_file *m, char c)
658{
659 if (m->count >= m->size)
660 return;
661
662 m->buf[m->count++] = c;
663}
664EXPORT_SYMBOL(seq_putc);
665
666void seq_puts(struct seq_file *m, const char *s)
667{
668 int len = strlen(s);
669
670 if (m->count + len >= m->size) {
671 seq_set_overflow(m);
672 return;
673 }
674 memcpy(m->buf + m->count, s, len);
675 m->count += len;
676}
677EXPORT_SYMBOL(seq_puts);
678
679
680
681
682
683
684
685
686
687
688
689
690
691void seq_put_decimal_ull_width(struct seq_file *m, const char *delimiter,
692 unsigned long long num, unsigned int width)
693{
694 int len;
695
696 if (m->count + 2 >= m->size)
697 goto overflow;
698
699 if (delimiter && delimiter[0]) {
700 if (delimiter[1] == 0)
701 seq_putc(m, delimiter[0]);
702 else
703 seq_puts(m, delimiter);
704 }
705
706 if (!width)
707 width = 1;
708
709 if (m->count + width >= m->size)
710 goto overflow;
711
712 len = num_to_str(m->buf + m->count, m->size - m->count, num, width);
713 if (!len)
714 goto overflow;
715
716 m->count += len;
717 return;
718
719overflow:
720 seq_set_overflow(m);
721}
722
723void seq_put_decimal_ull(struct seq_file *m, const char *delimiter,
724 unsigned long long num)
725{
726 return seq_put_decimal_ull_width(m, delimiter, num, 0);
727}
728EXPORT_SYMBOL(seq_put_decimal_ull);
729
730
731
732
733
734
735
736
737
738
739
740
741
742void seq_put_hex_ll(struct seq_file *m, const char *delimiter,
743 unsigned long long v, unsigned int width)
744{
745 unsigned int len;
746 int i;
747
748 if (delimiter && delimiter[0]) {
749 if (delimiter[1] == 0)
750 seq_putc(m, delimiter[0]);
751 else
752 seq_puts(m, delimiter);
753 }
754
755
756 if (v == 0)
757 len = 1;
758 else
759 len = (sizeof(v) * 8 - __builtin_clzll(v) + 3) / 4;
760
761 if (len < width)
762 len = width;
763
764 if (m->count + len > m->size) {
765 seq_set_overflow(m);
766 return;
767 }
768
769 for (i = len - 1; i >= 0; i--) {
770 m->buf[m->count + i] = hex_asc[0xf & v];
771 v = v >> 4;
772 }
773 m->count += len;
774}
775
776void seq_put_decimal_ll(struct seq_file *m, const char *delimiter, long long num)
777{
778 int len;
779
780 if (m->count + 3 >= m->size)
781 goto overflow;
782
783 if (delimiter && delimiter[0]) {
784 if (delimiter[1] == 0)
785 seq_putc(m, delimiter[0]);
786 else
787 seq_puts(m, delimiter);
788 }
789
790 if (m->count + 2 >= m->size)
791 goto overflow;
792
793 if (num < 0) {
794 m->buf[m->count++] = '-';
795 num = -num;
796 }
797
798 if (num < 10) {
799 m->buf[m->count++] = num + '0';
800 return;
801 }
802
803 len = num_to_str(m->buf + m->count, m->size - m->count, num, 0);
804 if (!len)
805 goto overflow;
806
807 m->count += len;
808 return;
809
810overflow:
811 seq_set_overflow(m);
812}
813EXPORT_SYMBOL(seq_put_decimal_ll);
814
815
816
817
818
819
820
821
822
823int seq_write(struct seq_file *seq, const void *data, size_t len)
824{
825 if (seq->count + len < seq->size) {
826 memcpy(seq->buf + seq->count, data, len);
827 seq->count += len;
828 return 0;
829 }
830 seq_set_overflow(seq);
831 return -1;
832}
833EXPORT_SYMBOL(seq_write);
834
835
836
837
838
839
840void seq_pad(struct seq_file *m, char c)
841{
842 int size = m->pad_until - m->count;
843 if (size > 0) {
844 if (size + m->count > m->size) {
845 seq_set_overflow(m);
846 return;
847 }
848 memset(m->buf + m->count, ' ', size);
849 m->count += size;
850 }
851 if (c)
852 seq_putc(m, c);
853}
854EXPORT_SYMBOL(seq_pad);
855
856
857void seq_hex_dump(struct seq_file *m, const char *prefix_str, int prefix_type,
858 int rowsize, int groupsize, const void *buf, size_t len,
859 bool ascii)
860{
861 const u8 *ptr = buf;
862 int i, linelen, remaining = len;
863 char *buffer;
864 size_t size;
865 int ret;
866
867 if (rowsize != 16 && rowsize != 32)
868 rowsize = 16;
869
870 for (i = 0; i < len && !seq_has_overflowed(m); i += rowsize) {
871 linelen = min(remaining, rowsize);
872 remaining -= rowsize;
873
874 switch (prefix_type) {
875 case DUMP_PREFIX_ADDRESS:
876 seq_printf(m, "%s%p: ", prefix_str, ptr + i);
877 break;
878 case DUMP_PREFIX_OFFSET:
879 seq_printf(m, "%s%.8x: ", prefix_str, i);
880 break;
881 default:
882 seq_printf(m, "%s", prefix_str);
883 break;
884 }
885
886 size = seq_get_buf(m, &buffer);
887 ret = hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
888 buffer, size, ascii);
889 seq_commit(m, ret < size ? ret : -1);
890
891 seq_putc(m, '\n');
892 }
893}
894EXPORT_SYMBOL(seq_hex_dump);
895
896struct list_head *seq_list_start(struct list_head *head, loff_t pos)
897{
898 struct list_head *lh;
899
900 list_for_each(lh, head)
901 if (pos-- == 0)
902 return lh;
903
904 return NULL;
905}
906EXPORT_SYMBOL(seq_list_start);
907
908struct list_head *seq_list_start_head(struct list_head *head, loff_t pos)
909{
910 if (!pos)
911 return head;
912
913 return seq_list_start(head, pos - 1);
914}
915EXPORT_SYMBOL(seq_list_start_head);
916
917struct list_head *seq_list_next(void *v, struct list_head *head, loff_t *ppos)
918{
919 struct list_head *lh;
920
921 lh = ((struct list_head *)v)->next;
922 ++*ppos;
923 return lh == head ? NULL : lh;
924}
925EXPORT_SYMBOL(seq_list_next);
926
927
928
929
930
931
932
933
934struct hlist_node *seq_hlist_start(struct hlist_head *head, loff_t pos)
935{
936 struct hlist_node *node;
937
938 hlist_for_each(node, head)
939 if (pos-- == 0)
940 return node;
941 return NULL;
942}
943EXPORT_SYMBOL(seq_hlist_start);
944
945
946
947
948
949
950
951
952
953struct hlist_node *seq_hlist_start_head(struct hlist_head *head, loff_t pos)
954{
955 if (!pos)
956 return SEQ_START_TOKEN;
957
958 return seq_hlist_start(head, pos - 1);
959}
960EXPORT_SYMBOL(seq_hlist_start_head);
961
962
963
964
965
966
967
968
969
970struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
971 loff_t *ppos)
972{
973 struct hlist_node *node = v;
974
975 ++*ppos;
976 if (v == SEQ_START_TOKEN)
977 return head->first;
978 else
979 return node->next;
980}
981EXPORT_SYMBOL(seq_hlist_next);
982
983
984
985
986
987
988
989
990
991
992
993
994struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
995 loff_t pos)
996{
997 struct hlist_node *node;
998
999 __hlist_for_each_rcu(node, head)
1000 if (pos-- == 0)
1001 return node;
1002 return NULL;
1003}
1004EXPORT_SYMBOL(seq_hlist_start_rcu);
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
1019 loff_t pos)
1020{
1021 if (!pos)
1022 return SEQ_START_TOKEN;
1023
1024 return seq_hlist_start_rcu(head, pos - 1);
1025}
1026EXPORT_SYMBOL(seq_hlist_start_head_rcu);
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040struct hlist_node *seq_hlist_next_rcu(void *v,
1041 struct hlist_head *head,
1042 loff_t *ppos)
1043{
1044 struct hlist_node *node = v;
1045
1046 ++*ppos;
1047 if (v == SEQ_START_TOKEN)
1048 return rcu_dereference(head->first);
1049 else
1050 return rcu_dereference(node->next);
1051}
1052EXPORT_SYMBOL(seq_hlist_next_rcu);
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062struct hlist_node *
1063seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos)
1064{
1065 struct hlist_node *node;
1066
1067 for_each_possible_cpu(*cpu) {
1068 hlist_for_each(node, per_cpu_ptr(head, *cpu)) {
1069 if (pos-- == 0)
1070 return node;
1071 }
1072 }
1073 return NULL;
1074}
1075EXPORT_SYMBOL(seq_hlist_start_percpu);
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086struct hlist_node *
1087seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head,
1088 int *cpu, loff_t *pos)
1089{
1090 struct hlist_node *node = v;
1091
1092 ++*pos;
1093
1094 if (node->next)
1095 return node->next;
1096
1097 for (*cpu = cpumask_next(*cpu, cpu_possible_mask); *cpu < nr_cpu_ids;
1098 *cpu = cpumask_next(*cpu, cpu_possible_mask)) {
1099 struct hlist_head *bucket = per_cpu_ptr(head, *cpu);
1100
1101 if (!hlist_empty(bucket))
1102 return bucket->first;
1103 }
1104 return NULL;
1105}
1106EXPORT_SYMBOL(seq_hlist_next_percpu);
1107
1108void __init seq_file_init(void)
1109{
1110 seq_file_cache = KMEM_CACHE(seq_file, SLAB_ACCOUNT|SLAB_PANIC);
1111}
1112