1
2
3
4
5#include <linux/errno.h>
6#include <linux/fs.h>
7#include <linux/mount.h>
8#include <linux/dqblk_v2.h>
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/slab.h>
13#include <linux/quotaops.h>
14
15#include <asm/byteorder.h>
16
17#include "quota_tree.h"
18
19MODULE_AUTHOR("Jan Kara");
20MODULE_DESCRIPTION("Quota trie support");
21MODULE_LICENSE("GPL");
22
23#define __QUOTA_QT_PARANOIA
24
25static int __get_index(struct qtree_mem_dqinfo *info, qid_t id, int depth)
26{
27 unsigned int epb = info->dqi_usable_bs >> 2;
28
29 depth = info->dqi_qtree_depth - depth - 1;
30 while (depth--)
31 id /= epb;
32 return id % epb;
33}
34
35static int get_index(struct qtree_mem_dqinfo *info, struct kqid qid, int depth)
36{
37 qid_t id = from_kqid(&init_user_ns, qid);
38
39 return __get_index(info, id, depth);
40}
41
42
43static int qtree_dqstr_in_blk(struct qtree_mem_dqinfo *info)
44{
45 return (info->dqi_usable_bs - sizeof(struct qt_disk_dqdbheader))
46 / info->dqi_entry_size;
47}
48
49static char *getdqbuf(size_t size)
50{
51 char *buf = kmalloc(size, GFP_NOFS);
52 if (!buf)
53 printk(KERN_WARNING
54 "VFS: Not enough memory for quota buffers.\n");
55 return buf;
56}
57
58static ssize_t read_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf)
59{
60 struct super_block *sb = info->dqi_sb;
61
62 memset(buf, 0, info->dqi_usable_bs);
63 return sb->s_op->quota_read(sb, info->dqi_type, buf,
64 info->dqi_usable_bs, blk << info->dqi_blocksize_bits);
65}
66
67static ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf)
68{
69 struct super_block *sb = info->dqi_sb;
70 ssize_t ret;
71
72 ret = sb->s_op->quota_write(sb, info->dqi_type, buf,
73 info->dqi_usable_bs, blk << info->dqi_blocksize_bits);
74 if (ret != info->dqi_usable_bs) {
75 quota_error(sb, "dquota write failed");
76 if (ret >= 0)
77 ret = -EIO;
78 }
79 return ret;
80}
81
82
83static int get_free_dqblk(struct qtree_mem_dqinfo *info)
84{
85 char *buf = getdqbuf(info->dqi_usable_bs);
86 struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf;
87 int ret, blk;
88
89 if (!buf)
90 return -ENOMEM;
91 if (info->dqi_free_blk) {
92 blk = info->dqi_free_blk;
93 ret = read_blk(info, blk, buf);
94 if (ret < 0)
95 goto out_buf;
96 info->dqi_free_blk = le32_to_cpu(dh->dqdh_next_free);
97 }
98 else {
99 memset(buf, 0, info->dqi_usable_bs);
100
101 ret = write_blk(info, info->dqi_blocks, buf);
102 if (ret < 0)
103 goto out_buf;
104 blk = info->dqi_blocks++;
105 }
106 mark_info_dirty(info->dqi_sb, info->dqi_type);
107 ret = blk;
108out_buf:
109 kfree(buf);
110 return ret;
111}
112
113
114static int put_free_dqblk(struct qtree_mem_dqinfo *info, char *buf, uint blk)
115{
116 struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf;
117 int err;
118
119 dh->dqdh_next_free = cpu_to_le32(info->dqi_free_blk);
120 dh->dqdh_prev_free = cpu_to_le32(0);
121 dh->dqdh_entries = cpu_to_le16(0);
122 err = write_blk(info, blk, buf);
123 if (err < 0)
124 return err;
125 info->dqi_free_blk = blk;
126 mark_info_dirty(info->dqi_sb, info->dqi_type);
127 return 0;
128}
129
130
131static int remove_free_dqentry(struct qtree_mem_dqinfo *info, char *buf,
132 uint blk)
133{
134 char *tmpbuf = getdqbuf(info->dqi_usable_bs);
135 struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf;
136 uint nextblk = le32_to_cpu(dh->dqdh_next_free);
137 uint prevblk = le32_to_cpu(dh->dqdh_prev_free);
138 int err;
139
140 if (!tmpbuf)
141 return -ENOMEM;
142 if (nextblk) {
143 err = read_blk(info, nextblk, tmpbuf);
144 if (err < 0)
145 goto out_buf;
146 ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free =
147 dh->dqdh_prev_free;
148 err = write_blk(info, nextblk, tmpbuf);
149 if (err < 0)
150 goto out_buf;
151 }
152 if (prevblk) {
153 err = read_blk(info, prevblk, tmpbuf);
154 if (err < 0)
155 goto out_buf;
156 ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_next_free =
157 dh->dqdh_next_free;
158 err = write_blk(info, prevblk, tmpbuf);
159 if (err < 0)
160 goto out_buf;
161 } else {
162 info->dqi_free_entry = nextblk;
163 mark_info_dirty(info->dqi_sb, info->dqi_type);
164 }
165 kfree(tmpbuf);
166 dh->dqdh_next_free = dh->dqdh_prev_free = cpu_to_le32(0);
167
168 if (write_blk(info, blk, buf) < 0)
169 quota_error(info->dqi_sb, "Can't write block (%u) "
170 "with free entries", blk);
171 return 0;
172out_buf:
173 kfree(tmpbuf);
174 return err;
175}
176
177
178static int insert_free_dqentry(struct qtree_mem_dqinfo *info, char *buf,
179 uint blk)
180{
181 char *tmpbuf = getdqbuf(info->dqi_usable_bs);
182 struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf;
183 int err;
184
185 if (!tmpbuf)
186 return -ENOMEM;
187 dh->dqdh_next_free = cpu_to_le32(info->dqi_free_entry);
188 dh->dqdh_prev_free = cpu_to_le32(0);
189 err = write_blk(info, blk, buf);
190 if (err < 0)
191 goto out_buf;
192 if (info->dqi_free_entry) {
193 err = read_blk(info, info->dqi_free_entry, tmpbuf);
194 if (err < 0)
195 goto out_buf;
196 ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free =
197 cpu_to_le32(blk);
198 err = write_blk(info, info->dqi_free_entry, tmpbuf);
199 if (err < 0)
200 goto out_buf;
201 }
202 kfree(tmpbuf);
203 info->dqi_free_entry = blk;
204 mark_info_dirty(info->dqi_sb, info->dqi_type);
205 return 0;
206out_buf:
207 kfree(tmpbuf);
208 return err;
209}
210
211
212int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk)
213{
214 int i;
215
216 for (i = 0; i < info->dqi_entry_size; i++)
217 if (disk[i])
218 return 0;
219 return 1;
220}
221EXPORT_SYMBOL(qtree_entry_unused);
222
223
224static uint find_free_dqentry(struct qtree_mem_dqinfo *info,
225 struct dquot *dquot, int *err)
226{
227 uint blk, i;
228 struct qt_disk_dqdbheader *dh;
229 char *buf = getdqbuf(info->dqi_usable_bs);
230 char *ddquot;
231
232 *err = 0;
233 if (!buf) {
234 *err = -ENOMEM;
235 return 0;
236 }
237 dh = (struct qt_disk_dqdbheader *)buf;
238 if (info->dqi_free_entry) {
239 blk = info->dqi_free_entry;
240 *err = read_blk(info, blk, buf);
241 if (*err < 0)
242 goto out_buf;
243 } else {
244 blk = get_free_dqblk(info);
245 if ((int)blk < 0) {
246 *err = blk;
247 kfree(buf);
248 return 0;
249 }
250 memset(buf, 0, info->dqi_usable_bs);
251
252
253 info->dqi_free_entry = blk;
254 mark_info_dirty(dquot->dq_sb, dquot->dq_id.type);
255 }
256
257 if (le16_to_cpu(dh->dqdh_entries) + 1 >= qtree_dqstr_in_blk(info)) {
258 *err = remove_free_dqentry(info, buf, blk);
259 if (*err < 0) {
260 quota_error(dquot->dq_sb, "Can't remove block (%u) "
261 "from entry free list", blk);
262 goto out_buf;
263 }
264 }
265 le16_add_cpu(&dh->dqdh_entries, 1);
266
267 ddquot = buf + sizeof(struct qt_disk_dqdbheader);
268 for (i = 0; i < qtree_dqstr_in_blk(info); i++) {
269 if (qtree_entry_unused(info, ddquot))
270 break;
271 ddquot += info->dqi_entry_size;
272 }
273#ifdef __QUOTA_QT_PARANOIA
274 if (i == qtree_dqstr_in_blk(info)) {
275 quota_error(dquot->dq_sb, "Data block full but it shouldn't");
276 *err = -EIO;
277 goto out_buf;
278 }
279#endif
280 *err = write_blk(info, blk, buf);
281 if (*err < 0) {
282 quota_error(dquot->dq_sb, "Can't write quota data block %u",
283 blk);
284 goto out_buf;
285 }
286 dquot->dq_off = (blk << info->dqi_blocksize_bits) +
287 sizeof(struct qt_disk_dqdbheader) +
288 i * info->dqi_entry_size;
289 kfree(buf);
290 return blk;
291out_buf:
292 kfree(buf);
293 return 0;
294}
295
296
297static int do_insert_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot,
298 uint *treeblk, int depth)
299{
300 char *buf = getdqbuf(info->dqi_usable_bs);
301 int ret = 0, newson = 0, newact = 0;
302 __le32 *ref;
303 uint newblk;
304
305 if (!buf)
306 return -ENOMEM;
307 if (!*treeblk) {
308 ret = get_free_dqblk(info);
309 if (ret < 0)
310 goto out_buf;
311 *treeblk = ret;
312 memset(buf, 0, info->dqi_usable_bs);
313 newact = 1;
314 } else {
315 ret = read_blk(info, *treeblk, buf);
316 if (ret < 0) {
317 quota_error(dquot->dq_sb, "Can't read tree quota "
318 "block %u", *treeblk);
319 goto out_buf;
320 }
321 }
322 ref = (__le32 *)buf;
323 newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
324 if (!newblk)
325 newson = 1;
326 if (depth == info->dqi_qtree_depth - 1) {
327#ifdef __QUOTA_QT_PARANOIA
328 if (newblk) {
329 quota_error(dquot->dq_sb, "Inserting already present "
330 "quota entry (block %u)",
331 le32_to_cpu(ref[get_index(info,
332 dquot->dq_id, depth)]));
333 ret = -EIO;
334 goto out_buf;
335 }
336#endif
337 newblk = find_free_dqentry(info, dquot, &ret);
338 } else {
339 ret = do_insert_tree(info, dquot, &newblk, depth+1);
340 }
341 if (newson && ret >= 0) {
342 ref[get_index(info, dquot->dq_id, depth)] =
343 cpu_to_le32(newblk);
344 ret = write_blk(info, *treeblk, buf);
345 } else if (newact && ret < 0) {
346 put_free_dqblk(info, buf, *treeblk);
347 }
348out_buf:
349 kfree(buf);
350 return ret;
351}
352
353
354static inline int dq_insert_tree(struct qtree_mem_dqinfo *info,
355 struct dquot *dquot)
356{
357 int tmp = QT_TREEOFF;
358
359#ifdef __QUOTA_QT_PARANOIA
360 if (info->dqi_blocks <= QT_TREEOFF) {
361 quota_error(dquot->dq_sb, "Quota tree root isn't allocated!");
362 return -EIO;
363 }
364#endif
365 return do_insert_tree(info, dquot, &tmp, 0);
366}
367
368
369
370
371
372int qtree_write_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
373{
374 int type = dquot->dq_id.type;
375 struct super_block *sb = dquot->dq_sb;
376 ssize_t ret;
377 char *ddquot = getdqbuf(info->dqi_entry_size);
378
379 if (!ddquot)
380 return -ENOMEM;
381
382
383 if (!dquot->dq_off) {
384 ret = dq_insert_tree(info, dquot);
385 if (ret < 0) {
386 quota_error(sb, "Error %zd occurred while creating "
387 "quota", ret);
388 kfree(ddquot);
389 return ret;
390 }
391 }
392 spin_lock(&dquot->dq_dqb_lock);
393 info->dqi_ops->mem2disk_dqblk(ddquot, dquot);
394 spin_unlock(&dquot->dq_dqb_lock);
395 ret = sb->s_op->quota_write(sb, type, ddquot, info->dqi_entry_size,
396 dquot->dq_off);
397 if (ret != info->dqi_entry_size) {
398 quota_error(sb, "dquota write failed");
399 if (ret >= 0)
400 ret = -ENOSPC;
401 } else {
402 ret = 0;
403 }
404 dqstats_inc(DQST_WRITES);
405 kfree(ddquot);
406
407 return ret;
408}
409EXPORT_SYMBOL(qtree_write_dquot);
410
411
412static int free_dqentry(struct qtree_mem_dqinfo *info, struct dquot *dquot,
413 uint blk)
414{
415 struct qt_disk_dqdbheader *dh;
416 char *buf = getdqbuf(info->dqi_usable_bs);
417 int ret = 0;
418
419 if (!buf)
420 return -ENOMEM;
421 if (dquot->dq_off >> info->dqi_blocksize_bits != blk) {
422 quota_error(dquot->dq_sb, "Quota structure has offset to "
423 "other block (%u) than it should (%u)", blk,
424 (uint)(dquot->dq_off >> info->dqi_blocksize_bits));
425 goto out_buf;
426 }
427 ret = read_blk(info, blk, buf);
428 if (ret < 0) {
429 quota_error(dquot->dq_sb, "Can't read quota data block %u",
430 blk);
431 goto out_buf;
432 }
433 dh = (struct qt_disk_dqdbheader *)buf;
434 le16_add_cpu(&dh->dqdh_entries, -1);
435 if (!le16_to_cpu(dh->dqdh_entries)) {
436 ret = remove_free_dqentry(info, buf, blk);
437 if (ret >= 0)
438 ret = put_free_dqblk(info, buf, blk);
439 if (ret < 0) {
440 quota_error(dquot->dq_sb, "Can't move quota data block "
441 "(%u) to free list", blk);
442 goto out_buf;
443 }
444 } else {
445 memset(buf +
446 (dquot->dq_off & ((1 << info->dqi_blocksize_bits) - 1)),
447 0, info->dqi_entry_size);
448 if (le16_to_cpu(dh->dqdh_entries) ==
449 qtree_dqstr_in_blk(info) - 1) {
450
451 ret = insert_free_dqentry(info, buf, blk);
452 if (ret < 0) {
453 quota_error(dquot->dq_sb, "Can't insert quota "
454 "data block (%u) to free entry list", blk);
455 goto out_buf;
456 }
457 } else {
458 ret = write_blk(info, blk, buf);
459 if (ret < 0) {
460 quota_error(dquot->dq_sb, "Can't write quota "
461 "data block %u", blk);
462 goto out_buf;
463 }
464 }
465 }
466 dquot->dq_off = 0;
467out_buf:
468 kfree(buf);
469 return ret;
470}
471
472
473static int remove_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot,
474 uint *blk, int depth)
475{
476 char *buf = getdqbuf(info->dqi_usable_bs);
477 int ret = 0;
478 uint newblk;
479 __le32 *ref = (__le32 *)buf;
480
481 if (!buf)
482 return -ENOMEM;
483 ret = read_blk(info, *blk, buf);
484 if (ret < 0) {
485 quota_error(dquot->dq_sb, "Can't read quota data block %u",
486 *blk);
487 goto out_buf;
488 }
489 newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
490 if (depth == info->dqi_qtree_depth - 1) {
491 ret = free_dqentry(info, dquot, newblk);
492 newblk = 0;
493 } else {
494 ret = remove_tree(info, dquot, &newblk, depth+1);
495 }
496 if (ret >= 0 && !newblk) {
497 int i;
498 ref[get_index(info, dquot->dq_id, depth)] = cpu_to_le32(0);
499
500 for (i = 0; i < (info->dqi_usable_bs >> 2) && !ref[i]; i++)
501 ;
502
503 if (i == (info->dqi_usable_bs >> 2)
504 && *blk != QT_TREEOFF) {
505 put_free_dqblk(info, buf, *blk);
506 *blk = 0;
507 } else {
508 ret = write_blk(info, *blk, buf);
509 if (ret < 0)
510 quota_error(dquot->dq_sb,
511 "Can't write quota tree block %u",
512 *blk);
513 }
514 }
515out_buf:
516 kfree(buf);
517 return ret;
518}
519
520
521int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
522{
523 uint tmp = QT_TREEOFF;
524
525 if (!dquot->dq_off)
526 return 0;
527 return remove_tree(info, dquot, &tmp, 0);
528}
529EXPORT_SYMBOL(qtree_delete_dquot);
530
531
532static loff_t find_block_dqentry(struct qtree_mem_dqinfo *info,
533 struct dquot *dquot, uint blk)
534{
535 char *buf = getdqbuf(info->dqi_usable_bs);
536 loff_t ret = 0;
537 int i;
538 char *ddquot;
539
540 if (!buf)
541 return -ENOMEM;
542 ret = read_blk(info, blk, buf);
543 if (ret < 0) {
544 quota_error(dquot->dq_sb, "Can't read quota tree "
545 "block %u", blk);
546 goto out_buf;
547 }
548 ddquot = buf + sizeof(struct qt_disk_dqdbheader);
549 for (i = 0; i < qtree_dqstr_in_blk(info); i++) {
550 if (info->dqi_ops->is_id(ddquot, dquot))
551 break;
552 ddquot += info->dqi_entry_size;
553 }
554 if (i == qtree_dqstr_in_blk(info)) {
555 quota_error(dquot->dq_sb,
556 "Quota for id %u referenced but not present",
557 from_kqid(&init_user_ns, dquot->dq_id));
558 ret = -EIO;
559 goto out_buf;
560 } else {
561 ret = (blk << info->dqi_blocksize_bits) + sizeof(struct
562 qt_disk_dqdbheader) + i * info->dqi_entry_size;
563 }
564out_buf:
565 kfree(buf);
566 return ret;
567}
568
569
570static loff_t find_tree_dqentry(struct qtree_mem_dqinfo *info,
571 struct dquot *dquot, uint blk, int depth)
572{
573 char *buf = getdqbuf(info->dqi_usable_bs);
574 loff_t ret = 0;
575 __le32 *ref = (__le32 *)buf;
576
577 if (!buf)
578 return -ENOMEM;
579 ret = read_blk(info, blk, buf);
580 if (ret < 0) {
581 quota_error(dquot->dq_sb, "Can't read quota tree block %u",
582 blk);
583 goto out_buf;
584 }
585 ret = 0;
586 blk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
587 if (!blk)
588 goto out_buf;
589 if (depth < info->dqi_qtree_depth - 1)
590 ret = find_tree_dqentry(info, dquot, blk, depth+1);
591 else
592 ret = find_block_dqentry(info, dquot, blk);
593out_buf:
594 kfree(buf);
595 return ret;
596}
597
598
599static inline loff_t find_dqentry(struct qtree_mem_dqinfo *info,
600 struct dquot *dquot)
601{
602 return find_tree_dqentry(info, dquot, QT_TREEOFF, 0);
603}
604
605int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
606{
607 int type = dquot->dq_id.type;
608 struct super_block *sb = dquot->dq_sb;
609 loff_t offset;
610 char *ddquot;
611 int ret = 0;
612
613#ifdef __QUOTA_QT_PARANOIA
614
615 if (!sb_dqopt(dquot->dq_sb)->files[type]) {
616 quota_error(sb, "Quota invalidated while reading!");
617 return -EIO;
618 }
619#endif
620
621 if (!dquot->dq_off) {
622 offset = find_dqentry(info, dquot);
623 if (offset <= 0) {
624 if (offset < 0)
625 quota_error(sb,"Can't read quota structure "
626 "for id %u",
627 from_kqid(&init_user_ns,
628 dquot->dq_id));
629 dquot->dq_off = 0;
630 set_bit(DQ_FAKE_B, &dquot->dq_flags);
631 memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk));
632 ret = offset;
633 goto out;
634 }
635 dquot->dq_off = offset;
636 }
637 ddquot = getdqbuf(info->dqi_entry_size);
638 if (!ddquot)
639 return -ENOMEM;
640 ret = sb->s_op->quota_read(sb, type, ddquot, info->dqi_entry_size,
641 dquot->dq_off);
642 if (ret != info->dqi_entry_size) {
643 if (ret >= 0)
644 ret = -EIO;
645 quota_error(sb, "Error while reading quota structure for id %u",
646 from_kqid(&init_user_ns, dquot->dq_id));
647 set_bit(DQ_FAKE_B, &dquot->dq_flags);
648 memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk));
649 kfree(ddquot);
650 goto out;
651 }
652 spin_lock(&dquot->dq_dqb_lock);
653 info->dqi_ops->disk2mem_dqblk(dquot, ddquot);
654 if (!dquot->dq_dqb.dqb_bhardlimit &&
655 !dquot->dq_dqb.dqb_bsoftlimit &&
656 !dquot->dq_dqb.dqb_ihardlimit &&
657 !dquot->dq_dqb.dqb_isoftlimit)
658 set_bit(DQ_FAKE_B, &dquot->dq_flags);
659 spin_unlock(&dquot->dq_dqb_lock);
660 kfree(ddquot);
661out:
662 dqstats_inc(DQST_READS);
663 return ret;
664}
665EXPORT_SYMBOL(qtree_read_dquot);
666
667
668
669int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
670{
671 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) &&
672 !(dquot->dq_dqb.dqb_curinodes | dquot->dq_dqb.dqb_curspace))
673 return qtree_delete_dquot(info, dquot);
674 return 0;
675}
676EXPORT_SYMBOL(qtree_release_dquot);
677
678static int find_next_id(struct qtree_mem_dqinfo *info, qid_t *id,
679 unsigned int blk, int depth)
680{
681 char *buf = getdqbuf(info->dqi_usable_bs);
682 __le32 *ref = (__le32 *)buf;
683 ssize_t ret;
684 unsigned int epb = info->dqi_usable_bs >> 2;
685 unsigned int level_inc = 1;
686 int i;
687
688 if (!buf)
689 return -ENOMEM;
690
691 for (i = depth; i < info->dqi_qtree_depth - 1; i++)
692 level_inc *= epb;
693
694 ret = read_blk(info, blk, buf);
695 if (ret < 0) {
696 quota_error(info->dqi_sb,
697 "Can't read quota tree block %u", blk);
698 goto out_buf;
699 }
700 for (i = __get_index(info, *id, depth); i < epb; i++) {
701 if (ref[i] == cpu_to_le32(0)) {
702 *id += level_inc;
703 continue;
704 }
705 if (depth == info->dqi_qtree_depth - 1) {
706 ret = 0;
707 goto out_buf;
708 }
709 ret = find_next_id(info, id, le32_to_cpu(ref[i]), depth + 1);
710 if (ret != -ENOENT)
711 break;
712 }
713 if (i == epb) {
714 ret = -ENOENT;
715 goto out_buf;
716 }
717out_buf:
718 kfree(buf);
719 return ret;
720}
721
722int qtree_get_next_id(struct qtree_mem_dqinfo *info, struct kqid *qid)
723{
724 qid_t id = from_kqid(&init_user_ns, *qid);
725 int ret;
726
727 ret = find_next_id(info, &id, QT_TREEOFF, 0);
728 if (ret < 0)
729 return ret;
730 *qid = make_kqid(&init_user_ns, qid->type, id);
731 return 0;
732}
733EXPORT_SYMBOL(qtree_get_next_id);
734
