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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * extent_map.c
4 *
5 * Block/Cluster mapping functions
6 *
7 * Copyright (C) 2004 Oracle. All rights reserved.
8 */
9
10#include <linux/fs.h>
11#include <linux/init.h>
12#include <linux/slab.h>
13#include <linux/types.h>
14#include <linux/fiemap.h>
15
16#include <cluster/masklog.h>
17
18#include "ocfs2.h"
19
20#include "alloc.h"
21#include "dlmglue.h"
22#include "extent_map.h"
23#include "inode.h"
24#include "super.h"
25#include "symlink.h"
26#include "aops.h"
27#include "ocfs2_trace.h"
28
29#include "buffer_head_io.h"
30
31/*
32 * The extent caching implementation is intentionally trivial.
33 *
34 * We only cache a small number of extents stored directly on the
35 * inode, so linear order operations are acceptable. If we ever want
36 * to increase the size of the extent map, then these algorithms must
37 * get smarter.
38 */
39
40void ocfs2_extent_map_init(struct inode *inode)
41{
42 struct ocfs2_inode_info *oi = OCFS2_I(inode);
43
44 oi->ip_extent_map.em_num_items = 0;
45 INIT_LIST_HEAD(&oi->ip_extent_map.em_list);
46}
47
48static void __ocfs2_extent_map_lookup(struct ocfs2_extent_map *em,
49 unsigned int cpos,
50 struct ocfs2_extent_map_item **ret_emi)
51{
52 unsigned int range;
53 struct ocfs2_extent_map_item *emi;
54
55 *ret_emi = NULL;
56
57 list_for_each_entry(emi, &em->em_list, ei_list) {
58 range = emi->ei_cpos + emi->ei_clusters;
59
60 if (cpos >= emi->ei_cpos && cpos < range) {
61 list_move(&emi->ei_list, &em->em_list);
62
63 *ret_emi = emi;
64 break;
65 }
66 }
67}
68
69static int ocfs2_extent_map_lookup(struct inode *inode, unsigned int cpos,
70 unsigned int *phys, unsigned int *len,
71 unsigned int *flags)
72{
73 unsigned int coff;
74 struct ocfs2_inode_info *oi = OCFS2_I(inode);
75 struct ocfs2_extent_map_item *emi;
76
77 spin_lock(&oi->ip_lock);
78
79 __ocfs2_extent_map_lookup(&oi->ip_extent_map, cpos, &emi);
80 if (emi) {
81 coff = cpos - emi->ei_cpos;
82 *phys = emi->ei_phys + coff;
83 if (len)
84 *len = emi->ei_clusters - coff;
85 if (flags)
86 *flags = emi->ei_flags;
87 }
88
89 spin_unlock(&oi->ip_lock);
90
91 if (emi == NULL)
92 return -ENOENT;
93
94 return 0;
95}
96
97/*
98 * Forget about all clusters equal to or greater than cpos.
99 */
100void ocfs2_extent_map_trunc(struct inode *inode, unsigned int cpos)
101{
102 struct ocfs2_extent_map_item *emi, *n;
103 struct ocfs2_inode_info *oi = OCFS2_I(inode);
104 struct ocfs2_extent_map *em = &oi->ip_extent_map;
105 LIST_HEAD(tmp_list);
106 unsigned int range;
107
108 spin_lock(&oi->ip_lock);
109 list_for_each_entry_safe(emi, n, &em->em_list, ei_list) {
110 if (emi->ei_cpos >= cpos) {
111 /* Full truncate of this record. */
112 list_move(&emi->ei_list, &tmp_list);
113 BUG_ON(em->em_num_items == 0);
114 em->em_num_items--;
115 continue;
116 }
117
118 range = emi->ei_cpos + emi->ei_clusters;
119 if (range > cpos) {
120 /* Partial truncate */
121 emi->ei_clusters = cpos - emi->ei_cpos;
122 }
123 }
124 spin_unlock(&oi->ip_lock);
125
126 list_for_each_entry_safe(emi, n, &tmp_list, ei_list) {
127 list_del(&emi->ei_list);
128 kfree(emi);
129 }
130}
131
132/*
133 * Is any part of emi2 contained within emi1
134 */
135static int ocfs2_ei_is_contained(struct ocfs2_extent_map_item *emi1,
136 struct ocfs2_extent_map_item *emi2)
137{
138 unsigned int range1, range2;
139
140 /*
141 * Check if logical start of emi2 is inside emi1
142 */
143 range1 = emi1->ei_cpos + emi1->ei_clusters;
144 if (emi2->ei_cpos >= emi1->ei_cpos && emi2->ei_cpos < range1)
145 return 1;
146
147 /*
148 * Check if logical end of emi2 is inside emi1
149 */
150 range2 = emi2->ei_cpos + emi2->ei_clusters;
151 if (range2 > emi1->ei_cpos && range2 <= range1)
152 return 1;
153
154 return 0;
155}
156
157static void ocfs2_copy_emi_fields(struct ocfs2_extent_map_item *dest,
158 struct ocfs2_extent_map_item *src)
159{
160 dest->ei_cpos = src->ei_cpos;
161 dest->ei_phys = src->ei_phys;
162 dest->ei_clusters = src->ei_clusters;
163 dest->ei_flags = src->ei_flags;
164}
165
166/*
167 * Try to merge emi with ins. Returns 1 if merge succeeds, zero
168 * otherwise.
169 */
170static int ocfs2_try_to_merge_extent_map(struct ocfs2_extent_map_item *emi,
171 struct ocfs2_extent_map_item *ins)
172{
173 /*
174 * Handle contiguousness
175 */
176 if (ins->ei_phys == (emi->ei_phys + emi->ei_clusters) &&
177 ins->ei_cpos == (emi->ei_cpos + emi->ei_clusters) &&
178 ins->ei_flags == emi->ei_flags) {
179 emi->ei_clusters += ins->ei_clusters;
180 return 1;
181 } else if ((ins->ei_phys + ins->ei_clusters) == emi->ei_phys &&
182 (ins->ei_cpos + ins->ei_clusters) == emi->ei_cpos &&
183 ins->ei_flags == emi->ei_flags) {
184 emi->ei_phys = ins->ei_phys;
185 emi->ei_cpos = ins->ei_cpos;
186 emi->ei_clusters += ins->ei_clusters;
187 return 1;
188 }
189
190 /*
191 * Overlapping extents - this shouldn't happen unless we've
192 * split an extent to change it's flags. That is exceedingly
193 * rare, so there's no sense in trying to optimize it yet.
194 */
195 if (ocfs2_ei_is_contained(emi, ins) ||
196 ocfs2_ei_is_contained(ins, emi)) {
197 ocfs2_copy_emi_fields(emi, ins);
198 return 1;
199 }
200
201 /* No merge was possible. */
202 return 0;
203}
204
205/*
206 * In order to reduce complexity on the caller, this insert function
207 * is intentionally liberal in what it will accept.
208 *
209 * The only rule is that the truncate call *must* be used whenever
210 * records have been deleted. This avoids inserting overlapping
211 * records with different physical mappings.
212 */
213void ocfs2_extent_map_insert_rec(struct inode *inode,
214 struct ocfs2_extent_rec *rec)
215{
216 struct ocfs2_inode_info *oi = OCFS2_I(inode);
217 struct ocfs2_extent_map *em = &oi->ip_extent_map;
218 struct ocfs2_extent_map_item *emi, *new_emi = NULL;
219 struct ocfs2_extent_map_item ins;
220
221 ins.ei_cpos = le32_to_cpu(rec->e_cpos);
222 ins.ei_phys = ocfs2_blocks_to_clusters(inode->i_sb,
223 le64_to_cpu(rec->e_blkno));
224 ins.ei_clusters = le16_to_cpu(rec->e_leaf_clusters);
225 ins.ei_flags = rec->e_flags;
226
227search:
228 spin_lock(&oi->ip_lock);
229
230 list_for_each_entry(emi, &em->em_list, ei_list) {
231 if (ocfs2_try_to_merge_extent_map(emi, &ins)) {
232 list_move(&emi->ei_list, &em->em_list);
233 spin_unlock(&oi->ip_lock);
234 goto out;
235 }
236 }
237
238 /*
239 * No item could be merged.
240 *
241 * Either allocate and add a new item, or overwrite the last recently
242 * inserted.
243 */
244
245 if (em->em_num_items < OCFS2_MAX_EXTENT_MAP_ITEMS) {
246 if (new_emi == NULL) {
247 spin_unlock(&oi->ip_lock);
248
249 new_emi = kmalloc_obj(*new_emi, GFP_NOFS);
250 if (new_emi == NULL)
251 goto out;
252
253 goto search;
254 }
255
256 ocfs2_copy_emi_fields(new_emi, &ins);
257 list_add(&new_emi->ei_list, &em->em_list);
258 em->em_num_items++;
259 new_emi = NULL;
260 } else {
261 BUG_ON(list_empty(&em->em_list) || em->em_num_items == 0);
262 emi = list_entry(em->em_list.prev,
263 struct ocfs2_extent_map_item, ei_list);
264 list_move(&emi->ei_list, &em->em_list);
265 ocfs2_copy_emi_fields(emi, &ins);
266 }
267
268 spin_unlock(&oi->ip_lock);
269
270out:
271 kfree(new_emi);
272}
273
274static int ocfs2_last_eb_is_empty(struct inode *inode,
275 struct ocfs2_dinode *di)
276{
277 int ret, next_free;
278 u64 last_eb_blk = le64_to_cpu(di->i_last_eb_blk);
279 struct buffer_head *eb_bh = NULL;
280 struct ocfs2_extent_block *eb;
281 struct ocfs2_extent_list *el;
282
283 ret = ocfs2_read_extent_block(INODE_CACHE(inode), last_eb_blk, &eb_bh);
284 if (ret) {
285 mlog_errno(ret);
286 goto out;
287 }
288
289 eb = (struct ocfs2_extent_block *) eb_bh->b_data;
290 el = &eb->h_list;
291
292 if (el->l_tree_depth) {
293 ocfs2_error(inode->i_sb,
294 "Inode %llu has non zero tree depth in leaf block %llu\n",
295 inode->i_ino,
296 (unsigned long long)eb_bh->b_blocknr);
297 ret = -EROFS;
298 goto out;
299 }
300
301 next_free = le16_to_cpu(el->l_next_free_rec);
302
303 if (next_free == 0 ||
304 (next_free == 1 && ocfs2_is_empty_extent(&el->l_recs[0])))
305 ret = 1;
306
307out:
308 brelse(eb_bh);
309 return ret;
310}
311
312/*
313 * Return the 1st index within el which contains an extent start
314 * larger than v_cluster.
315 */
316static int ocfs2_search_for_hole_index(struct ocfs2_extent_list *el,
317 u32 v_cluster)
318{
319 int i;
320 struct ocfs2_extent_rec *rec;
321
322 for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
323 rec = &el->l_recs[i];
324
325 if (v_cluster < le32_to_cpu(rec->e_cpos))
326 break;
327 }
328
329 return i;
330}
331
332/*
333 * Figure out the size of a hole which starts at v_cluster within the given
334 * extent list.
335 *
336 * If there is no more allocation past v_cluster, we return the maximum
337 * cluster size minus v_cluster.
338 *
339 * If we have in-inode extents, then el points to the dinode list and
340 * eb_bh is NULL. Otherwise, eb_bh should point to the extent block
341 * containing el.
342 */
343int ocfs2_figure_hole_clusters(struct ocfs2_caching_info *ci,
344 struct ocfs2_extent_list *el,
345 struct buffer_head *eb_bh,
346 u32 v_cluster,
347 u32 *num_clusters)
348{
349 int ret, i;
350 struct buffer_head *next_eb_bh = NULL;
351 struct ocfs2_extent_block *eb, *next_eb;
352
353 i = ocfs2_search_for_hole_index(el, v_cluster);
354
355 if (i == le16_to_cpu(el->l_next_free_rec) && eb_bh) {
356 eb = (struct ocfs2_extent_block *)eb_bh->b_data;
357
358 /*
359 * Check the next leaf for any extents.
360 */
361
362 if (le64_to_cpu(eb->h_next_leaf_blk) == 0ULL)
363 goto no_more_extents;
364
365 ret = ocfs2_read_extent_block(ci,
366 le64_to_cpu(eb->h_next_leaf_blk),
367 &next_eb_bh);
368 if (ret) {
369 mlog_errno(ret);
370 goto out;
371 }
372
373 next_eb = (struct ocfs2_extent_block *)next_eb_bh->b_data;
374 el = &next_eb->h_list;
375 i = ocfs2_search_for_hole_index(el, v_cluster);
376 }
377
378no_more_extents:
379 if (i == le16_to_cpu(el->l_next_free_rec)) {
380 /*
381 * We're at the end of our existing allocation. Just
382 * return the maximum number of clusters we could
383 * possibly allocate.
384 */
385 *num_clusters = UINT_MAX - v_cluster;
386 } else {
387 *num_clusters = le32_to_cpu(el->l_recs[i].e_cpos) - v_cluster;
388 }
389
390 ret = 0;
391out:
392 brelse(next_eb_bh);
393 return ret;
394}
395
396static int ocfs2_get_clusters_nocache(struct inode *inode,
397 struct buffer_head *di_bh,
398 u32 v_cluster, unsigned int *hole_len,
399 struct ocfs2_extent_rec *ret_rec,
400 unsigned int *is_last)
401{
402 int i, ret, tree_height, len;
403 struct ocfs2_dinode *di;
404 struct ocfs2_extent_block *eb;
405 struct ocfs2_extent_list *el;
406 struct ocfs2_extent_rec *rec;
407 struct buffer_head *eb_bh = NULL;
408
409 memset(ret_rec, 0, sizeof(*ret_rec));
410 if (is_last)
411 *is_last = 0;
412
413 di = (struct ocfs2_dinode *) di_bh->b_data;
414 el = &di->id2.i_list;
415 tree_height = le16_to_cpu(el->l_tree_depth);
416
417 if (tree_height > 0) {
418 ret = ocfs2_find_leaf(INODE_CACHE(inode), el, v_cluster,
419 &eb_bh);
420 if (ret) {
421 mlog_errno(ret);
422 goto out;
423 }
424
425 eb = (struct ocfs2_extent_block *) eb_bh->b_data;
426 el = &eb->h_list;
427
428 if (el->l_tree_depth) {
429 ocfs2_error(inode->i_sb,
430 "Inode %llu has non zero tree depth in leaf block %llu\n",
431 inode->i_ino,
432 (unsigned long long)eb_bh->b_blocknr);
433 ret = -EROFS;
434 goto out;
435 }
436 }
437
438 if (le16_to_cpu(el->l_next_free_rec) > le16_to_cpu(el->l_count)) {
439 ocfs2_error(inode->i_sb,
440 "Inode %llu has an invalid extent (next_free_rec %u, count %u)\n",
441 inode->i_ino,
442 le16_to_cpu(el->l_next_free_rec),
443 le16_to_cpu(el->l_count));
444 ret = -EROFS;
445 goto out;
446 }
447
448 i = ocfs2_search_extent_list(el, v_cluster);
449 if (i == -1) {
450 /*
451 * Holes can be larger than the maximum size of an
452 * extent, so we return their lengths in a separate
453 * field.
454 */
455 if (hole_len) {
456 ret = ocfs2_figure_hole_clusters(INODE_CACHE(inode),
457 el, eb_bh,
458 v_cluster, &len);
459 if (ret) {
460 mlog_errno(ret);
461 goto out;
462 }
463
464 *hole_len = len;
465 }
466 goto out_hole;
467 }
468
469 rec = &el->l_recs[i];
470
471 BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos));
472
473 if (!rec->e_blkno) {
474 ocfs2_error(inode->i_sb,
475 "Inode %llu has bad extent record (%u, %u, 0)\n",
476 inode->i_ino,
477 le32_to_cpu(rec->e_cpos),
478 ocfs2_rec_clusters(el, rec));
479 ret = -EROFS;
480 goto out;
481 }
482
483 *ret_rec = *rec;
484
485 /*
486 * Checking for last extent is potentially expensive - we
487 * might have to look at the next leaf over to see if it's
488 * empty.
489 *
490 * The first two checks are to see whether the caller even
491 * cares for this information, and if the extent is at least
492 * the last in it's list.
493 *
494 * If those hold true, then the extent is last if any of the
495 * additional conditions hold true:
496 * - Extent list is in-inode
497 * - Extent list is right-most
498 * - Extent list is 2nd to rightmost, with empty right-most
499 */
500 if (is_last) {
501 if (i == (le16_to_cpu(el->l_next_free_rec) - 1)) {
502 if (tree_height == 0)
503 *is_last = 1;
504 else if (eb->h_blkno == di->i_last_eb_blk)
505 *is_last = 1;
506 else if (eb->h_next_leaf_blk == di->i_last_eb_blk) {
507 ret = ocfs2_last_eb_is_empty(inode, di);
508 if (ret < 0) {
509 mlog_errno(ret);
510 goto out;
511 }
512 if (ret == 1)
513 *is_last = 1;
514 }
515 }
516 }
517
518out_hole:
519 ret = 0;
520out:
521 brelse(eb_bh);
522 return ret;
523}
524
525static void ocfs2_relative_extent_offsets(struct super_block *sb,
526 u32 v_cluster,
527 struct ocfs2_extent_rec *rec,
528 u32 *p_cluster, u32 *num_clusters)
529
530{
531 u32 coff = v_cluster - le32_to_cpu(rec->e_cpos);
532
533 *p_cluster = ocfs2_blocks_to_clusters(sb, le64_to_cpu(rec->e_blkno));
534 *p_cluster = *p_cluster + coff;
535
536 if (num_clusters)
537 *num_clusters = le16_to_cpu(rec->e_leaf_clusters) - coff;
538}
539
540int ocfs2_xattr_get_clusters(struct inode *inode, u32 v_cluster,
541 u32 *p_cluster, u32 *num_clusters,
542 struct ocfs2_extent_list *el,
543 unsigned int *extent_flags)
544{
545 int ret = 0, i;
546 struct buffer_head *eb_bh = NULL;
547 struct ocfs2_extent_block *eb;
548 struct ocfs2_extent_rec *rec;
549 u32 coff;
550
551 if (el->l_tree_depth) {
552 ret = ocfs2_find_leaf(INODE_CACHE(inode), el, v_cluster,
553 &eb_bh);
554 if (ret) {
555 mlog_errno(ret);
556 goto out;
557 }
558
559 eb = (struct ocfs2_extent_block *) eb_bh->b_data;
560 el = &eb->h_list;
561
562 if (el->l_tree_depth) {
563 ocfs2_error(inode->i_sb,
564 "Inode %llu has non zero tree depth in xattr leaf block %llu\n",
565 inode->i_ino,
566 (unsigned long long)eb_bh->b_blocknr);
567 ret = -EROFS;
568 goto out;
569 }
570 }
571
572 i = ocfs2_search_extent_list(el, v_cluster);
573 if (i == -1) {
574 ret = -EROFS;
575 mlog_errno(ret);
576 goto out;
577 } else {
578 rec = &el->l_recs[i];
579 BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos));
580
581 if (!rec->e_blkno) {
582 ocfs2_error(inode->i_sb,
583 "Inode %llu has bad extent record (%u, %u, 0) in xattr\n",
584 inode->i_ino,
585 le32_to_cpu(rec->e_cpos),
586 ocfs2_rec_clusters(el, rec));
587 ret = -EROFS;
588 goto out;
589 }
590 coff = v_cluster - le32_to_cpu(rec->e_cpos);
591 *p_cluster = ocfs2_blocks_to_clusters(inode->i_sb,
592 le64_to_cpu(rec->e_blkno));
593 *p_cluster = *p_cluster + coff;
594 if (num_clusters)
595 *num_clusters = ocfs2_rec_clusters(el, rec) - coff;
596
597 if (extent_flags)
598 *extent_flags = rec->e_flags;
599 }
600out:
601 brelse(eb_bh);
602 return ret;
603}
604
605int ocfs2_get_clusters(struct inode *inode, u32 v_cluster,
606 u32 *p_cluster, u32 *num_clusters,
607 unsigned int *extent_flags)
608{
609 int ret;
610 unsigned int hole_len, flags = 0;
611 struct buffer_head *di_bh = NULL;
612 struct ocfs2_extent_rec rec;
613
614 if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
615 ret = -ERANGE;
616 mlog_errno(ret);
617 goto out;
618 }
619
620 ret = ocfs2_extent_map_lookup(inode, v_cluster, p_cluster,
621 num_clusters, extent_flags);
622 if (ret == 0)
623 goto out;
624
625 ret = ocfs2_read_inode_block(inode, &di_bh);
626 if (ret) {
627 mlog_errno(ret);
628 goto out;
629 }
630
631 ret = ocfs2_get_clusters_nocache(inode, di_bh, v_cluster, &hole_len,
632 &rec, NULL);
633 if (ret) {
634 mlog_errno(ret);
635 goto out;
636 }
637
638 if (rec.e_blkno == 0ULL) {
639 /*
640 * A hole was found. Return some canned values that
641 * callers can key on. If asked for, num_clusters will
642 * be populated with the size of the hole.
643 */
644 *p_cluster = 0;
645 if (num_clusters) {
646 *num_clusters = hole_len;
647 }
648 } else {
649 ocfs2_relative_extent_offsets(inode->i_sb, v_cluster, &rec,
650 p_cluster, num_clusters);
651 flags = rec.e_flags;
652
653 ocfs2_extent_map_insert_rec(inode, &rec);
654 }
655
656 if (extent_flags)
657 *extent_flags = flags;
658
659out:
660 brelse(di_bh);
661 return ret;
662}
663
664/*
665 * This expects alloc_sem to be held. The allocation cannot change at
666 * all while the map is in the process of being updated.
667 */
668int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno,
669 u64 *ret_count, unsigned int *extent_flags)
670{
671 int ret;
672 int bpc = ocfs2_clusters_to_blocks(inode->i_sb, 1);
673 u32 cpos, num_clusters, p_cluster;
674 u64 boff = 0;
675
676 cpos = ocfs2_blocks_to_clusters(inode->i_sb, v_blkno);
677
678 ret = ocfs2_get_clusters(inode, cpos, &p_cluster, &num_clusters,
679 extent_flags);
680 if (ret) {
681 mlog_errno(ret);
682 goto out;
683 }
684
685 /*
686 * p_cluster == 0 indicates a hole.
687 */
688 if (p_cluster) {
689 boff = ocfs2_clusters_to_blocks(inode->i_sb, p_cluster);
690 boff += (v_blkno & (u64)(bpc - 1));
691 }
692
693 *p_blkno = boff;
694
695 if (ret_count) {
696 *ret_count = ocfs2_clusters_to_blocks(inode->i_sb, num_clusters);
697 *ret_count -= v_blkno & (u64)(bpc - 1);
698 }
699
700out:
701 return ret;
702}
703
704/*
705 * The ocfs2_fiemap_inline() may be a little bit misleading, since
706 * it not only handles the fiemap for inlined files, but also deals
707 * with the fast symlink, cause they have no difference for extent
708 * mapping per se.
709 *
710 * Must be called with ip_alloc_sem semaphore held.
711 */
712static int ocfs2_fiemap_inline(struct inode *inode, struct buffer_head *di_bh,
713 struct fiemap_extent_info *fieinfo,
714 u64 map_start)
715{
716 int ret;
717 unsigned int id_count;
718 struct ocfs2_dinode *di;
719 u64 phys;
720 u32 flags = FIEMAP_EXTENT_DATA_INLINE|FIEMAP_EXTENT_LAST;
721 struct ocfs2_inode_info *oi = OCFS2_I(inode);
722 lockdep_assert_held_read(&oi->ip_alloc_sem);
723
724 di = (struct ocfs2_dinode *)di_bh->b_data;
725 if (ocfs2_inode_is_fast_symlink(inode))
726 id_count = ocfs2_fast_symlink_chars(inode->i_sb);
727 else
728 id_count = le16_to_cpu(di->id2.i_data.id_count);
729
730 if (map_start < id_count) {
731 phys = oi->ip_blkno << inode->i_sb->s_blocksize_bits;
732 if (ocfs2_inode_is_fast_symlink(inode))
733 phys += offsetof(struct ocfs2_dinode, id2.i_symlink);
734 else
735 phys += offsetof(struct ocfs2_dinode,
736 id2.i_data.id_data);
737
738 /* Release the ip_alloc_sem to prevent deadlock on page fault */
739 up_read(&OCFS2_I(inode)->ip_alloc_sem);
740 ret = fiemap_fill_next_extent(fieinfo, 0, phys, id_count,
741 flags);
742 down_read(&OCFS2_I(inode)->ip_alloc_sem);
743 if (ret < 0)
744 return ret;
745 }
746
747 return 0;
748}
749
750int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
751 u64 map_start, u64 map_len)
752{
753 int ret, is_last;
754 u32 mapping_end, cpos;
755 unsigned int hole_size;
756 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
757 u64 len_bytes, phys_bytes, virt_bytes;
758 struct buffer_head *di_bh = NULL;
759 struct ocfs2_extent_rec rec;
760
761 ret = fiemap_prep(inode, fieinfo, map_start, &map_len, 0);
762 if (ret)
763 return ret;
764
765 ret = ocfs2_inode_lock(inode, &di_bh, 0);
766 if (ret) {
767 mlog_errno(ret);
768 goto out;
769 }
770
771 down_read(&OCFS2_I(inode)->ip_alloc_sem);
772
773 /*
774 * Handle inline-data and fast symlink separately.
775 */
776 if ((OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) ||
777 ocfs2_inode_is_fast_symlink(inode)) {
778 ret = ocfs2_fiemap_inline(inode, di_bh, fieinfo, map_start);
779 goto out_unlock;
780 }
781
782 cpos = map_start >> osb->s_clustersize_bits;
783 mapping_end = ocfs2_clusters_for_bytes(inode->i_sb,
784 map_start + map_len);
785 is_last = 0;
786 while (cpos < mapping_end && !is_last) {
787 u32 fe_flags;
788
789 ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos,
790 &hole_size, &rec, &is_last);
791 if (ret) {
792 mlog_errno(ret);
793 goto out_unlock;
794 }
795
796 if (rec.e_blkno == 0ULL) {
797 cpos += hole_size;
798 continue;
799 }
800
801 fe_flags = 0;
802 if (rec.e_flags & OCFS2_EXT_UNWRITTEN)
803 fe_flags |= FIEMAP_EXTENT_UNWRITTEN;
804 if (rec.e_flags & OCFS2_EXT_REFCOUNTED)
805 fe_flags |= FIEMAP_EXTENT_SHARED;
806 if (is_last)
807 fe_flags |= FIEMAP_EXTENT_LAST;
808 len_bytes = (u64)le16_to_cpu(rec.e_leaf_clusters) << osb->s_clustersize_bits;
809 phys_bytes = le64_to_cpu(rec.e_blkno) << osb->sb->s_blocksize_bits;
810 virt_bytes = (u64)le32_to_cpu(rec.e_cpos) << osb->s_clustersize_bits;
811 /* Release the ip_alloc_sem to prevent deadlock on page fault */
812 up_read(&OCFS2_I(inode)->ip_alloc_sem);
813 ret = fiemap_fill_next_extent(fieinfo, virt_bytes, phys_bytes,
814 len_bytes, fe_flags);
815 down_read(&OCFS2_I(inode)->ip_alloc_sem);
816 if (ret)
817 break;
818
819 cpos = le32_to_cpu(rec.e_cpos)+ le16_to_cpu(rec.e_leaf_clusters);
820 }
821
822 if (ret > 0)
823 ret = 0;
824
825out_unlock:
826 brelse(di_bh);
827
828 up_read(&OCFS2_I(inode)->ip_alloc_sem);
829
830 ocfs2_inode_unlock(inode, 0);
831out:
832
833 return ret;
834}
835
836/* Is IO overwriting allocated blocks? */
837int ocfs2_overwrite_io(struct inode *inode, struct buffer_head *di_bh,
838 u64 map_start, u64 map_len)
839{
840 int ret = 0, is_last;
841 u32 mapping_end, cpos;
842 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
843 struct ocfs2_extent_rec rec;
844
845 if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
846 if (ocfs2_size_fits_inline_data(di_bh, map_start + map_len))
847 return ret;
848 else
849 return -EAGAIN;
850 }
851
852 cpos = map_start >> osb->s_clustersize_bits;
853 mapping_end = ocfs2_clusters_for_bytes(inode->i_sb,
854 map_start + map_len);
855 is_last = 0;
856 while (cpos < mapping_end && !is_last) {
857 ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos,
858 NULL, &rec, &is_last);
859 if (ret) {
860 mlog_errno(ret);
861 goto out;
862 }
863
864 if (rec.e_blkno == 0ULL)
865 break;
866
867 if (rec.e_flags & OCFS2_EXT_REFCOUNTED)
868 break;
869
870 cpos = le32_to_cpu(rec.e_cpos) +
871 le16_to_cpu(rec.e_leaf_clusters);
872 }
873
874 if (cpos < mapping_end)
875 ret = -EAGAIN;
876out:
877 return ret;
878}
879
880int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int whence)
881{
882 struct inode *inode = file->f_mapping->host;
883 int ret;
884 unsigned int is_last = 0, is_data = 0;
885 u16 cs_bits = OCFS2_SB(inode->i_sb)->s_clustersize_bits;
886 u32 cpos, cend, clen, hole_size;
887 u64 extoff, extlen;
888 struct buffer_head *di_bh = NULL;
889 struct ocfs2_extent_rec rec;
890
891 BUG_ON(whence != SEEK_DATA && whence != SEEK_HOLE);
892
893 ret = ocfs2_inode_lock(inode, &di_bh, 0);
894 if (ret) {
895 mlog_errno(ret);
896 goto out;
897 }
898
899 down_read(&OCFS2_I(inode)->ip_alloc_sem);
900
901 if (*offset >= i_size_read(inode)) {
902 ret = -ENXIO;
903 goto out_unlock;
904 }
905
906 if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
907 if (whence == SEEK_HOLE)
908 *offset = i_size_read(inode);
909 goto out_unlock;
910 }
911
912 clen = 0;
913 cpos = *offset >> cs_bits;
914 cend = ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode));
915
916 while (cpos < cend && !is_last) {
917 ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos, &hole_size,
918 &rec, &is_last);
919 if (ret) {
920 mlog_errno(ret);
921 goto out_unlock;
922 }
923
924 extoff = cpos;
925 extoff <<= cs_bits;
926
927 if (rec.e_blkno == 0ULL) {
928 clen = hole_size;
929 is_data = 0;
930 } else {
931 clen = le16_to_cpu(rec.e_leaf_clusters) -
932 (cpos - le32_to_cpu(rec.e_cpos));
933 is_data = (rec.e_flags & OCFS2_EXT_UNWRITTEN) ? 0 : 1;
934 }
935
936 if ((!is_data && whence == SEEK_HOLE) ||
937 (is_data && whence == SEEK_DATA)) {
938 if (extoff > *offset)
939 *offset = extoff;
940 goto out_unlock;
941 }
942
943 if (!is_last)
944 cpos += clen;
945 }
946
947 if (whence == SEEK_HOLE) {
948 extoff = cpos;
949 extoff <<= cs_bits;
950 extlen = clen;
951 extlen <<= cs_bits;
952
953 if ((extoff + extlen) > i_size_read(inode))
954 extlen = i_size_read(inode) - extoff;
955 extoff += extlen;
956 if (extoff > *offset)
957 *offset = extoff;
958 goto out_unlock;
959 }
960
961 ret = -ENXIO;
962
963out_unlock:
964
965 brelse(di_bh);
966
967 up_read(&OCFS2_I(inode)->ip_alloc_sem);
968
969 ocfs2_inode_unlock(inode, 0);
970out:
971 return ret;
972}
973
974int ocfs2_read_virt_blocks(struct inode *inode, u64 v_block, int nr,
975 struct buffer_head *bhs[], int flags,
976 int (*validate)(struct super_block *sb,
977 struct buffer_head *bh))
978{
979 int rc = 0;
980 u64 p_block, p_count;
981 int i, count, done = 0;
982
983 trace_ocfs2_read_virt_blocks(
984 inode, (unsigned long long)v_block, nr, bhs, flags,
985 validate);
986
987 if (((v_block + nr - 1) << inode->i_sb->s_blocksize_bits) >=
988 i_size_read(inode)) {
989 BUG_ON(!(flags & OCFS2_BH_READAHEAD));
990 goto out;
991 }
992
993 while (done < nr) {
994 if (!down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem)) {
995 rc = -EAGAIN;
996 mlog(ML_ERROR,
997 "Inode #%llu ip_alloc_sem is temporarily unavailable\n",
998 (unsigned long long)OCFS2_I(inode)->ip_blkno);
999 break;
1000 }
1001 rc = ocfs2_extent_map_get_blocks(inode, v_block + done,
1002 &p_block, &p_count, NULL);
1003 up_read(&OCFS2_I(inode)->ip_alloc_sem);
1004 if (rc) {
1005 mlog_errno(rc);
1006 break;
1007 }
1008
1009 if (!p_block) {
1010 rc = -EIO;
1011 mlog(ML_ERROR,
1012 "Inode #%llu contains a hole at offset %llu\n",
1013 (unsigned long long)OCFS2_I(inode)->ip_blkno,
1014 (unsigned long long)(v_block + done) <<
1015 inode->i_sb->s_blocksize_bits);
1016 break;
1017 }
1018
1019 count = nr - done;
1020 if (p_count < count)
1021 count = p_count;
1022
1023 /*
1024 * If the caller passed us bhs, they should have come
1025 * from a previous readahead call to this function. Thus,
1026 * they should have the right b_blocknr.
1027 */
1028 for (i = 0; i < count; i++) {
1029 if (!bhs[done + i])
1030 continue;
1031 BUG_ON(bhs[done + i]->b_blocknr != (p_block + i));
1032 }
1033
1034 rc = ocfs2_read_blocks(INODE_CACHE(inode), p_block, count,
1035 bhs + done, flags, validate);
1036 if (rc) {
1037 mlog_errno(rc);
1038 break;
1039 }
1040 done += count;
1041 }
1042
1043out:
1044 return rc;
1045}
1046
1047