Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * move_extents.c
4 *
5 * Copyright (C) 2011 Oracle. All rights reserved.
6 */
7#include <linux/fs.h>
8#include <linux/types.h>
9#include <linux/mount.h>
10#include <linux/swap.h>
11
12#include <cluster/masklog.h>
13
14#include "ocfs2.h"
15#include "ocfs2_ioctl.h"
16
17#include "alloc.h"
18#include "localalloc.h"
19#include "aops.h"
20#include "dlmglue.h"
21#include "extent_map.h"
22#include "inode.h"
23#include "journal.h"
24#include "suballoc.h"
25#include "uptodate.h"
26#include "super.h"
27#include "dir.h"
28#include "buffer_head_io.h"
29#include "sysfile.h"
30#include "refcounttree.h"
31#include "move_extents.h"
32
33struct ocfs2_move_extents_context {
34 struct inode *inode;
35 struct file *file;
36 int auto_defrag;
37 int partial;
38 int credits;
39 u32 new_phys_cpos;
40 u32 clusters_moved;
41 u64 refcount_loc;
42 struct ocfs2_move_extents *range;
43 struct ocfs2_extent_tree et;
44 struct ocfs2_alloc_context *meta_ac;
45 struct ocfs2_alloc_context *data_ac;
46 struct ocfs2_cached_dealloc_ctxt dealloc;
47};
48
49static int __ocfs2_move_extent(handle_t *handle,
50 struct ocfs2_move_extents_context *context,
51 u32 cpos, u32 len, u32 p_cpos, u32 new_p_cpos,
52 int ext_flags)
53{
54 int ret = 0, index;
55 struct inode *inode = context->inode;
56 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
57 struct ocfs2_extent_rec *rec, replace_rec;
58 struct ocfs2_path *path = NULL;
59 struct ocfs2_extent_list *el;
60 u64 ino = ocfs2_metadata_cache_owner(context->et.et_ci);
61 u64 old_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cpos);
62
63 ret = ocfs2_duplicate_clusters_by_page(handle, inode, cpos,
64 p_cpos, new_p_cpos, len);
65 if (ret) {
66 mlog_errno(ret);
67 goto out;
68 }
69
70 memset(&replace_rec, 0, sizeof(replace_rec));
71 replace_rec.e_cpos = cpu_to_le32(cpos);
72 replace_rec.e_leaf_clusters = cpu_to_le16(len);
73 replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
74 new_p_cpos));
75
76 path = ocfs2_new_path_from_et(&context->et);
77 if (!path) {
78 ret = -ENOMEM;
79 mlog_errno(ret);
80 goto out;
81 }
82
83 ret = ocfs2_find_path(INODE_CACHE(inode), path, cpos);
84 if (ret) {
85 mlog_errno(ret);
86 goto out;
87 }
88
89 el = path_leaf_el(path);
90
91 index = ocfs2_search_extent_list(el, cpos);
92 if (index == -1) {
93 ret = ocfs2_error(inode->i_sb,
94 "Inode %llu has an extent at cpos %u which can no longer be found\n",
95 (unsigned long long)ino, cpos);
96 goto out;
97 }
98
99 rec = &el->l_recs[index];
100
101 BUG_ON(ext_flags != rec->e_flags);
102 /*
103 * after moving/defraging to new location, the extent is not going
104 * to be refcounted anymore.
105 */
106 replace_rec.e_flags = ext_flags & ~OCFS2_EXT_REFCOUNTED;
107
108 ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode),
109 context->et.et_root_bh,
110 OCFS2_JOURNAL_ACCESS_WRITE);
111 if (ret) {
112 mlog_errno(ret);
113 goto out;
114 }
115
116 ret = ocfs2_split_extent(handle, &context->et, path, index,
117 &replace_rec, context->meta_ac,
118 &context->dealloc);
119 if (ret) {
120 mlog_errno(ret);
121 goto out;
122 }
123
124 ocfs2_journal_dirty(handle, context->et.et_root_bh);
125
126 context->new_phys_cpos = new_p_cpos;
127
128 /*
129 * need I to append truncate log for old clusters?
130 */
131 if (old_blkno) {
132 if (ext_flags & OCFS2_EXT_REFCOUNTED)
133 ret = ocfs2_decrease_refcount(inode, handle,
134 ocfs2_blocks_to_clusters(osb->sb,
135 old_blkno),
136 len, context->meta_ac,
137 &context->dealloc, 1);
138 else
139 ret = ocfs2_truncate_log_append(osb, handle,
140 old_blkno, len);
141 }
142
143 ocfs2_update_inode_fsync_trans(handle, inode, 0);
144out:
145 ocfs2_free_path(path);
146 return ret;
147}
148
149/*
150 * lock allocator, and reserve appropriate number of bits for
151 * meta blocks.
152 */
153static int ocfs2_lock_meta_allocator_move_extents(struct inode *inode,
154 struct ocfs2_extent_tree *et,
155 u32 clusters_to_move,
156 u32 extents_to_split,
157 struct ocfs2_alloc_context **meta_ac,
158 int extra_blocks,
159 int *credits)
160{
161 int ret, num_free_extents;
162 unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
163 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
164
165 num_free_extents = ocfs2_num_free_extents(et);
166 if (num_free_extents < 0) {
167 ret = num_free_extents;
168 mlog_errno(ret);
169 goto out;
170 }
171
172 if (!num_free_extents ||
173 (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
174 extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
175
176 ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
177 if (ret) {
178 mlog_errno(ret);
179 goto out;
180 }
181
182
183 *credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el);
184
185 mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
186 extra_blocks, clusters_to_move, *credits);
187out:
188 if (ret) {
189 if (*meta_ac) {
190 ocfs2_free_alloc_context(*meta_ac);
191 *meta_ac = NULL;
192 }
193 }
194
195 return ret;
196}
197
198/*
199 * Using one journal handle to guarantee the data consistency in case
200 * crash happens anywhere.
201 *
202 * XXX: defrag can end up with finishing partial extent as requested,
203 * due to not enough contiguous clusters can be found in allocator.
204 */
205static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
206 u32 cpos, u32 phys_cpos, u32 *len, int ext_flags)
207{
208 int ret, credits = 0, extra_blocks = 0, partial = context->partial;
209 handle_t *handle;
210 struct inode *inode = context->inode;
211 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
212 struct inode *tl_inode = osb->osb_tl_inode;
213 struct ocfs2_refcount_tree *ref_tree = NULL;
214 u32 new_phys_cpos, new_len;
215 u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
216 int need_free = 0;
217
218 if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
219 BUG_ON(!ocfs2_is_refcount_inode(inode));
220 BUG_ON(!context->refcount_loc);
221
222 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
223 &ref_tree, NULL);
224 if (ret) {
225 mlog_errno(ret);
226 return ret;
227 }
228
229 ret = ocfs2_prepare_refcount_change_for_del(inode,
230 context->refcount_loc,
231 phys_blkno,
232 *len,
233 &credits,
234 &extra_blocks);
235 if (ret) {
236 mlog_errno(ret);
237 goto out;
238 }
239 }
240
241 ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
242 *len, 1,
243 &context->meta_ac,
244 extra_blocks, &credits);
245 if (ret) {
246 mlog_errno(ret);
247 goto out;
248 }
249
250 /*
251 * should be using allocation reservation strategy there?
252 *
253 * if (context->data_ac)
254 * context->data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
255 */
256
257 inode_lock(tl_inode);
258
259 if (ocfs2_truncate_log_needs_flush(osb)) {
260 ret = __ocfs2_flush_truncate_log(osb);
261 if (ret < 0) {
262 mlog_errno(ret);
263 goto out_unlock_mutex;
264 }
265 }
266
267 /*
268 * Make sure ocfs2_reserve_cluster is called after
269 * __ocfs2_flush_truncate_log, otherwise, dead lock may happen.
270 *
271 * If ocfs2_reserve_cluster is called
272 * before __ocfs2_flush_truncate_log, dead lock on global bitmap
273 * may happen.
274 *
275 */
276 ret = ocfs2_reserve_clusters(osb, *len, &context->data_ac);
277 if (ret) {
278 mlog_errno(ret);
279 goto out_unlock_mutex;
280 }
281
282 handle = ocfs2_start_trans(osb, credits);
283 if (IS_ERR(handle)) {
284 ret = PTR_ERR(handle);
285 mlog_errno(ret);
286 goto out_unlock_mutex;
287 }
288
289 ret = __ocfs2_claim_clusters(handle, context->data_ac, 1, *len,
290 &new_phys_cpos, &new_len);
291 if (ret) {
292 mlog_errno(ret);
293 goto out_commit;
294 }
295
296 /*
297 * allowing partial extent moving is kind of 'pros and cons', it makes
298 * whole defragmentation less likely to fail, on the contrary, the bad
299 * thing is it may make the fs even more fragmented after moving, let
300 * userspace make a good decision here.
301 */
302 if (new_len != *len) {
303 mlog(0, "len_claimed: %u, len: %u\n", new_len, *len);
304 if (!partial) {
305 context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
306 ret = -ENOSPC;
307 need_free = 1;
308 goto out_commit;
309 }
310 }
311
312 mlog(0, "cpos: %u, phys_cpos: %u, new_phys_cpos: %u\n", cpos,
313 phys_cpos, new_phys_cpos);
314
315 ret = __ocfs2_move_extent(handle, context, cpos, new_len, phys_cpos,
316 new_phys_cpos, ext_flags);
317 if (ret)
318 mlog_errno(ret);
319
320 if (partial && (new_len != *len))
321 *len = new_len;
322
323 /*
324 * Here we should write the new page out first if we are
325 * in write-back mode.
326 */
327 ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, *len);
328 if (ret)
329 mlog_errno(ret);
330
331out_commit:
332 if (need_free && context->data_ac) {
333 struct ocfs2_alloc_context *data_ac = context->data_ac;
334
335 if (context->data_ac->ac_which == OCFS2_AC_USE_LOCAL)
336 ocfs2_free_local_alloc_bits(osb, handle, data_ac,
337 new_phys_cpos, new_len);
338 else
339 ocfs2_free_clusters(handle,
340 data_ac->ac_inode,
341 data_ac->ac_bh,
342 ocfs2_clusters_to_blocks(osb->sb, new_phys_cpos),
343 new_len);
344 }
345
346 ocfs2_commit_trans(osb, handle);
347
348out_unlock_mutex:
349 inode_unlock(tl_inode);
350
351 if (context->data_ac) {
352 ocfs2_free_alloc_context(context->data_ac);
353 context->data_ac = NULL;
354 }
355
356 if (context->meta_ac) {
357 ocfs2_free_alloc_context(context->meta_ac);
358 context->meta_ac = NULL;
359 }
360
361out:
362 if (ref_tree)
363 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
364
365 return ret;
366}
367
368/*
369 * find the victim alloc group, where #blkno fits.
370 */
371static int ocfs2_find_victim_alloc_group(struct inode *inode,
372 u64 vict_blkno,
373 int type, int slot,
374 int *vict_bit,
375 struct buffer_head **ret_bh)
376{
377 int ret, i, bits_per_unit = 0;
378 u64 blkno;
379 char namebuf[40];
380
381 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
382 struct buffer_head *ac_bh = NULL, *gd_bh = NULL;
383 struct ocfs2_chain_list *cl;
384 struct ocfs2_chain_rec *rec;
385 struct ocfs2_dinode *ac_dinode;
386 struct ocfs2_group_desc *bg;
387
388 ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type, slot);
389 ret = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
390 strlen(namebuf), &blkno);
391 if (ret) {
392 ret = -ENOENT;
393 goto out;
394 }
395
396 ret = ocfs2_read_blocks_sync(osb, blkno, 1, &ac_bh);
397 if (ret) {
398 mlog_errno(ret);
399 goto out;
400 }
401
402 ac_dinode = (struct ocfs2_dinode *)ac_bh->b_data;
403 cl = &(ac_dinode->id2.i_chain);
404 rec = &(cl->cl_recs[0]);
405
406 if (type == GLOBAL_BITMAP_SYSTEM_INODE)
407 bits_per_unit = osb->s_clustersize_bits -
408 inode->i_sb->s_blocksize_bits;
409 /*
410 * 'vict_blkno' was out of the valid range.
411 */
412 if ((vict_blkno < le64_to_cpu(rec->c_blkno)) ||
413 (vict_blkno >= ((u64)le32_to_cpu(ac_dinode->id1.bitmap1.i_total) <<
414 bits_per_unit))) {
415 ret = -EINVAL;
416 goto out;
417 }
418
419 for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
420
421 rec = &(cl->cl_recs[i]);
422 if (!rec)
423 continue;
424
425 bg = NULL;
426
427 do {
428 if (!bg)
429 blkno = le64_to_cpu(rec->c_blkno);
430 else
431 blkno = le64_to_cpu(bg->bg_next_group);
432
433 if (gd_bh) {
434 brelse(gd_bh);
435 gd_bh = NULL;
436 }
437
438 ret = ocfs2_read_blocks_sync(osb, blkno, 1, &gd_bh);
439 if (ret) {
440 mlog_errno(ret);
441 goto out;
442 }
443
444 bg = (struct ocfs2_group_desc *)gd_bh->b_data;
445
446 if (vict_blkno < (le64_to_cpu(bg->bg_blkno) +
447 le16_to_cpu(bg->bg_bits))) {
448
449 *ret_bh = gd_bh;
450 *vict_bit = (vict_blkno - blkno) >>
451 bits_per_unit;
452 mlog(0, "find the victim group: #%llu, "
453 "total_bits: %u, vict_bit: %u\n",
454 blkno, le16_to_cpu(bg->bg_bits),
455 *vict_bit);
456 goto out;
457 }
458
459 } while (le64_to_cpu(bg->bg_next_group));
460 }
461
462 ret = -EINVAL;
463out:
464 brelse(ac_bh);
465
466 /*
467 * caller has to release the gd_bh properly.
468 */
469 return ret;
470}
471
472/*
473 * XXX: helper to validate and adjust moving goal.
474 */
475static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
476 struct ocfs2_move_extents *range)
477{
478 int ret, goal_bit = 0;
479
480 struct buffer_head *gd_bh = NULL;
481 struct ocfs2_group_desc *bg;
482 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
483 int c_to_b = 1 << (osb->s_clustersize_bits -
484 inode->i_sb->s_blocksize_bits);
485
486 /*
487 * make goal become cluster aligned.
488 */
489 range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
490 range->me_goal);
491 /*
492 * validate goal sits within global_bitmap, and return the victim
493 * group desc
494 */
495 ret = ocfs2_find_victim_alloc_group(inode, range->me_goal,
496 GLOBAL_BITMAP_SYSTEM_INODE,
497 OCFS2_INVALID_SLOT,
498 &goal_bit, &gd_bh);
499 if (ret)
500 goto out;
501
502 bg = (struct ocfs2_group_desc *)gd_bh->b_data;
503
504 /*
505 * moving goal is not allowd to start with a group desc blok(#0 blk)
506 * let's compromise to the latter cluster.
507 */
508 if (range->me_goal == le64_to_cpu(bg->bg_blkno))
509 range->me_goal += c_to_b;
510
511 /*
512 * movement is not gonna cross two groups.
513 */
514 if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <
515 range->me_len) {
516 ret = -EINVAL;
517 goto out;
518 }
519 /*
520 * more exact validations/adjustments will be performed later during
521 * moving operation for each extent range.
522 */
523 mlog(0, "extents get ready to be moved to #%llu block\n",
524 range->me_goal);
525
526out:
527 brelse(gd_bh);
528
529 return ret;
530}
531
532static void ocfs2_probe_alloc_group(struct inode *inode, struct buffer_head *bh,
533 int *goal_bit, u32 move_len, u32 max_hop,
534 u32 *phys_cpos)
535{
536 int i, used, last_free_bits = 0, base_bit = *goal_bit;
537 struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
538 u32 base_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
539 le64_to_cpu(gd->bg_blkno));
540
541 for (i = base_bit; i < le16_to_cpu(gd->bg_bits); i++) {
542
543 used = ocfs2_test_bit(i, (unsigned long *)gd->bg_bitmap);
544 if (used) {
545 /*
546 * we even tried searching the free chunk by jumping
547 * a 'max_hop' distance, but still failed.
548 */
549 if ((i - base_bit) > max_hop) {
550 *phys_cpos = 0;
551 break;
552 }
553
554 if (last_free_bits)
555 last_free_bits = 0;
556
557 continue;
558 } else
559 last_free_bits++;
560
561 if (last_free_bits == move_len) {
562 *goal_bit = i;
563 *phys_cpos = base_cpos + i;
564 break;
565 }
566 }
567
568 mlog(0, "found phys_cpos: %u to fit the wanted moving.\n", *phys_cpos);
569}
570
571static int ocfs2_move_extent(struct ocfs2_move_extents_context *context,
572 u32 cpos, u32 phys_cpos, u32 *new_phys_cpos,
573 u32 len, int ext_flags)
574{
575 int ret, credits = 0, extra_blocks = 0, goal_bit = 0;
576 handle_t *handle;
577 struct inode *inode = context->inode;
578 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
579 struct inode *tl_inode = osb->osb_tl_inode;
580 struct inode *gb_inode = NULL;
581 struct buffer_head *gb_bh = NULL;
582 struct buffer_head *gd_bh = NULL;
583 struct ocfs2_group_desc *gd;
584 struct ocfs2_refcount_tree *ref_tree = NULL;
585 u32 move_max_hop = ocfs2_blocks_to_clusters(inode->i_sb,
586 context->range->me_threshold);
587 u64 phys_blkno, new_phys_blkno;
588
589 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
590
591 if ((ext_flags & OCFS2_EXT_REFCOUNTED) && len) {
592 BUG_ON(!ocfs2_is_refcount_inode(inode));
593 BUG_ON(!context->refcount_loc);
594
595 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
596 &ref_tree, NULL);
597 if (ret) {
598 mlog_errno(ret);
599 return ret;
600 }
601
602 ret = ocfs2_prepare_refcount_change_for_del(inode,
603 context->refcount_loc,
604 phys_blkno,
605 len,
606 &credits,
607 &extra_blocks);
608 if (ret) {
609 mlog_errno(ret);
610 goto out;
611 }
612 }
613
614 ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
615 len, 1,
616 &context->meta_ac,
617 extra_blocks, &credits);
618 if (ret) {
619 mlog_errno(ret);
620 goto out;
621 }
622
623 /*
624 * need to count 2 extra credits for global_bitmap inode and
625 * group descriptor.
626 */
627 credits += OCFS2_INODE_UPDATE_CREDITS + 1;
628
629 /*
630 * ocfs2_move_extent() didn't reserve any clusters in lock_allocators()
631 * logic, while we still need to lock the global_bitmap.
632 */
633 gb_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
634 OCFS2_INVALID_SLOT);
635 if (!gb_inode) {
636 mlog(ML_ERROR, "unable to get global_bitmap inode\n");
637 ret = -EIO;
638 goto out;
639 }
640
641 inode_lock(gb_inode);
642
643 ret = ocfs2_inode_lock(gb_inode, &gb_bh, 1);
644 if (ret) {
645 mlog_errno(ret);
646 goto out_unlock_gb_mutex;
647 }
648
649 inode_lock(tl_inode);
650
651 handle = ocfs2_start_trans(osb, credits);
652 if (IS_ERR(handle)) {
653 ret = PTR_ERR(handle);
654 mlog_errno(ret);
655 goto out_unlock_tl_inode;
656 }
657
658 new_phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *new_phys_cpos);
659 ret = ocfs2_find_victim_alloc_group(inode, new_phys_blkno,
660 GLOBAL_BITMAP_SYSTEM_INODE,
661 OCFS2_INVALID_SLOT,
662 &goal_bit, &gd_bh);
663 if (ret) {
664 mlog_errno(ret);
665 goto out_commit;
666 }
667
668 /*
669 * probe the victim cluster group to find a proper
670 * region to fit wanted movement, it even will perfrom
671 * a best-effort attempt by compromising to a threshold
672 * around the goal.
673 */
674 ocfs2_probe_alloc_group(inode, gd_bh, &goal_bit, len, move_max_hop,
675 new_phys_cpos);
676 if (!*new_phys_cpos) {
677 ret = -ENOSPC;
678 goto out_commit;
679 }
680
681 ret = __ocfs2_move_extent(handle, context, cpos, len, phys_cpos,
682 *new_phys_cpos, ext_flags);
683 if (ret) {
684 mlog_errno(ret);
685 goto out_commit;
686 }
687
688 gd = (struct ocfs2_group_desc *)gd_bh->b_data;
689 ret = ocfs2_alloc_dinode_update_counts(gb_inode, handle, gb_bh, len,
690 le16_to_cpu(gd->bg_chain));
691 if (ret) {
692 mlog_errno(ret);
693 goto out_commit;
694 }
695
696 ret = ocfs2_block_group_set_bits(handle, gb_inode, gd, gd_bh,
697 goal_bit, len);
698 if (ret) {
699 ocfs2_rollback_alloc_dinode_counts(gb_inode, gb_bh, len,
700 le16_to_cpu(gd->bg_chain));
701 mlog_errno(ret);
702 }
703
704 /*
705 * Here we should write the new page out first if we are
706 * in write-back mode.
707 */
708 ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, len);
709 if (ret)
710 mlog_errno(ret);
711
712out_commit:
713 ocfs2_commit_trans(osb, handle);
714 brelse(gd_bh);
715
716out_unlock_tl_inode:
717 inode_unlock(tl_inode);
718
719 ocfs2_inode_unlock(gb_inode, 1);
720out_unlock_gb_mutex:
721 inode_unlock(gb_inode);
722 brelse(gb_bh);
723 iput(gb_inode);
724
725out:
726 if (context->meta_ac) {
727 ocfs2_free_alloc_context(context->meta_ac);
728 context->meta_ac = NULL;
729 }
730
731 if (ref_tree)
732 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
733
734 return ret;
735}
736
737/*
738 * Helper to calculate the defraging length in one run according to threshold.
739 */
740static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
741 u32 threshold, int *skip)
742{
743 if ((*alloc_size + *len_defraged) < threshold) {
744 /*
745 * proceed defragmentation until we meet the thresh
746 */
747 *len_defraged += *alloc_size;
748 } else if (*len_defraged == 0) {
749 /*
750 * XXX: skip a large extent.
751 */
752 *skip = 1;
753 } else {
754 /*
755 * split this extent to coalesce with former pieces as
756 * to reach the threshold.
757 *
758 * we're done here with one cycle of defragmentation
759 * in a size of 'thresh', resetting 'len_defraged'
760 * forces a new defragmentation.
761 */
762 *alloc_size = threshold - *len_defraged;
763 *len_defraged = 0;
764 }
765}
766
767static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
768 struct ocfs2_move_extents_context *context)
769{
770 int ret = 0, flags, do_defrag, skip = 0;
771 u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
772 u32 len_defraged = 0, defrag_thresh = 0, new_phys_cpos = 0;
773
774 struct inode *inode = context->inode;
775 struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
776 struct ocfs2_move_extents *range = context->range;
777 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
778
779 if ((i_size_read(inode) == 0) || (range->me_len == 0))
780 return 0;
781
782 if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
783 return 0;
784
785 context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
786
787 ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
788 ocfs2_init_dealloc_ctxt(&context->dealloc);
789
790 /*
791 * TO-DO XXX:
792 *
793 * - xattr extents.
794 */
795
796 do_defrag = context->auto_defrag;
797
798 /*
799 * extents moving happens in unit of clusters, for the sake
800 * of simplicity, we may ignore two clusters where 'byte_start'
801 * and 'byte_start + len' were within.
802 */
803 move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
804 len_to_move = (range->me_start + range->me_len) >>
805 osb->s_clustersize_bits;
806 if (len_to_move >= move_start)
807 len_to_move -= move_start;
808 else
809 len_to_move = 0;
810
811 if (do_defrag) {
812 defrag_thresh = range->me_threshold >> osb->s_clustersize_bits;
813 if (defrag_thresh <= 1)
814 goto done;
815 } else
816 new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
817 range->me_goal);
818
819 mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
820 "thresh: %u\n",
821 (unsigned long long)OCFS2_I(inode)->ip_blkno,
822 (unsigned long long)range->me_start,
823 (unsigned long long)range->me_len,
824 move_start, len_to_move, defrag_thresh);
825
826 cpos = move_start;
827 while (len_to_move) {
828 ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
829 &flags);
830 if (ret) {
831 mlog_errno(ret);
832 goto out;
833 }
834
835 if (alloc_size > len_to_move)
836 alloc_size = len_to_move;
837
838 /*
839 * XXX: how to deal with a hole:
840 *
841 * - skip the hole of course
842 * - force a new defragmentation
843 */
844 if (!phys_cpos) {
845 if (do_defrag)
846 len_defraged = 0;
847
848 goto next;
849 }
850
851 if (do_defrag) {
852 ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
853 defrag_thresh, &skip);
854 /*
855 * skip large extents
856 */
857 if (skip) {
858 skip = 0;
859 goto next;
860 }
861
862 mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
863 "alloc_size: %u, len_defraged: %u\n",
864 cpos, phys_cpos, alloc_size, len_defraged);
865
866 ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
867 &alloc_size, flags);
868 } else {
869 ret = ocfs2_move_extent(context, cpos, phys_cpos,
870 &new_phys_cpos, alloc_size,
871 flags);
872
873 new_phys_cpos += alloc_size;
874 }
875
876 if (ret < 0) {
877 mlog_errno(ret);
878 goto out;
879 }
880
881 context->clusters_moved += alloc_size;
882next:
883 cpos += alloc_size;
884 len_to_move -= alloc_size;
885 }
886
887done:
888 range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
889
890out:
891 range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
892 context->clusters_moved);
893 range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
894 context->new_phys_cpos);
895
896 ocfs2_schedule_truncate_log_flush(osb, 1);
897 ocfs2_run_deallocs(osb, &context->dealloc);
898
899 return ret;
900}
901
902static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
903{
904 int status;
905 handle_t *handle;
906 struct inode *inode = context->inode;
907 struct ocfs2_dinode *di;
908 struct buffer_head *di_bh = NULL;
909 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
910
911 if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
912 return -EROFS;
913
914 inode_lock(inode);
915
916 /*
917 * This prevents concurrent writes from other nodes
918 */
919 status = ocfs2_rw_lock(inode, 1);
920 if (status) {
921 mlog_errno(status);
922 goto out;
923 }
924
925 status = ocfs2_inode_lock(inode, &di_bh, 1);
926 if (status) {
927 mlog_errno(status);
928 goto out_rw_unlock;
929 }
930
931 /*
932 * rememer ip_xattr_sem also needs to be held if necessary
933 */
934 down_write(&OCFS2_I(inode)->ip_alloc_sem);
935
936 status = __ocfs2_move_extents_range(di_bh, context);
937
938 up_write(&OCFS2_I(inode)->ip_alloc_sem);
939 if (status) {
940 mlog_errno(status);
941 goto out_inode_unlock;
942 }
943
944 /*
945 * We update ctime for these changes
946 */
947 handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
948 if (IS_ERR(handle)) {
949 status = PTR_ERR(handle);
950 mlog_errno(status);
951 goto out_inode_unlock;
952 }
953
954 status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
955 OCFS2_JOURNAL_ACCESS_WRITE);
956 if (status) {
957 mlog_errno(status);
958 goto out_commit;
959 }
960
961 di = (struct ocfs2_dinode *)di_bh->b_data;
962 inode->i_ctime = current_time(inode);
963 di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
964 di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
965 ocfs2_update_inode_fsync_trans(handle, inode, 0);
966
967 ocfs2_journal_dirty(handle, di_bh);
968
969out_commit:
970 ocfs2_commit_trans(osb, handle);
971
972out_inode_unlock:
973 brelse(di_bh);
974 ocfs2_inode_unlock(inode, 1);
975out_rw_unlock:
976 ocfs2_rw_unlock(inode, 1);
977out:
978 inode_unlock(inode);
979
980 return status;
981}
982
983int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
984{
985 int status;
986
987 struct inode *inode = file_inode(filp);
988 struct ocfs2_move_extents range;
989 struct ocfs2_move_extents_context *context;
990
991 if (!argp)
992 return -EINVAL;
993
994 status = mnt_want_write_file(filp);
995 if (status)
996 return status;
997
998 if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE)) {
999 status = -EPERM;
1000 goto out_drop;
1001 }
1002
1003 if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
1004 status = -EPERM;
1005 goto out_drop;
1006 }
1007
1008 context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
1009 if (!context) {
1010 status = -ENOMEM;
1011 mlog_errno(status);
1012 goto out_drop;
1013 }
1014
1015 context->inode = inode;
1016 context->file = filp;
1017
1018 if (copy_from_user(&range, argp, sizeof(range))) {
1019 status = -EFAULT;
1020 goto out_free;
1021 }
1022
1023 if (range.me_start > i_size_read(inode)) {
1024 status = -EINVAL;
1025 goto out_free;
1026 }
1027
1028 if (range.me_start + range.me_len > i_size_read(inode))
1029 range.me_len = i_size_read(inode) - range.me_start;
1030
1031 context->range = ⦥
1032
1033 if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
1034 context->auto_defrag = 1;
1035 /*
1036 * ok, the default theshold for the defragmentation
1037 * is 1M, since our maximum clustersize was 1M also.
1038 * any thought?
1039 */
1040 if (!range.me_threshold)
1041 range.me_threshold = 1024 * 1024;
1042
1043 if (range.me_threshold > i_size_read(inode))
1044 range.me_threshold = i_size_read(inode);
1045
1046 if (range.me_flags & OCFS2_MOVE_EXT_FL_PART_DEFRAG)
1047 context->partial = 1;
1048 } else {
1049 /*
1050 * first best-effort attempt to validate and adjust the goal
1051 * (physical address in block), while it can't guarantee later
1052 * operation can succeed all the time since global_bitmap may
1053 * change a bit over time.
1054 */
1055
1056 status = ocfs2_validate_and_adjust_move_goal(inode, &range);
1057 if (status)
1058 goto out_copy;
1059 }
1060
1061 status = ocfs2_move_extents(context);
1062 if (status)
1063 mlog_errno(status);
1064out_copy:
1065 /*
1066 * movement/defragmentation may end up being partially completed,
1067 * that's the reason why we need to return userspace the finished
1068 * length and new_offset even if failure happens somewhere.
1069 */
1070 if (copy_to_user(argp, &range, sizeof(range)))
1071 status = -EFAULT;
1072
1073out_free:
1074 kfree(context);
1075out_drop:
1076 mnt_drop_write_file(filp);
1077
1078 return status;
1079}
1/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * move_extents.c
5 *
6 * Copyright (C) 2011 Oracle. All rights reserved.
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public
10 * License version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 */
17#include <linux/fs.h>
18#include <linux/types.h>
19#include <linux/mount.h>
20#include <linux/swap.h>
21
22#include <cluster/masklog.h>
23
24#include "ocfs2.h"
25#include "ocfs2_ioctl.h"
26
27#include "alloc.h"
28#include "aops.h"
29#include "dlmglue.h"
30#include "extent_map.h"
31#include "inode.h"
32#include "journal.h"
33#include "suballoc.h"
34#include "uptodate.h"
35#include "super.h"
36#include "dir.h"
37#include "buffer_head_io.h"
38#include "sysfile.h"
39#include "refcounttree.h"
40#include "move_extents.h"
41
42struct ocfs2_move_extents_context {
43 struct inode *inode;
44 struct file *file;
45 int auto_defrag;
46 int partial;
47 int credits;
48 u32 new_phys_cpos;
49 u32 clusters_moved;
50 u64 refcount_loc;
51 struct ocfs2_move_extents *range;
52 struct ocfs2_extent_tree et;
53 struct ocfs2_alloc_context *meta_ac;
54 struct ocfs2_alloc_context *data_ac;
55 struct ocfs2_cached_dealloc_ctxt dealloc;
56};
57
58static int __ocfs2_move_extent(handle_t *handle,
59 struct ocfs2_move_extents_context *context,
60 u32 cpos, u32 len, u32 p_cpos, u32 new_p_cpos,
61 int ext_flags)
62{
63 int ret = 0, index;
64 struct inode *inode = context->inode;
65 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
66 struct ocfs2_extent_rec *rec, replace_rec;
67 struct ocfs2_path *path = NULL;
68 struct ocfs2_extent_list *el;
69 u64 ino = ocfs2_metadata_cache_owner(context->et.et_ci);
70 u64 old_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cpos);
71
72 ret = ocfs2_duplicate_clusters_by_page(handle, context->file, cpos,
73 p_cpos, new_p_cpos, len);
74 if (ret) {
75 mlog_errno(ret);
76 goto out;
77 }
78
79 memset(&replace_rec, 0, sizeof(replace_rec));
80 replace_rec.e_cpos = cpu_to_le32(cpos);
81 replace_rec.e_leaf_clusters = cpu_to_le16(len);
82 replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
83 new_p_cpos));
84
85 path = ocfs2_new_path_from_et(&context->et);
86 if (!path) {
87 ret = -ENOMEM;
88 mlog_errno(ret);
89 goto out;
90 }
91
92 ret = ocfs2_find_path(INODE_CACHE(inode), path, cpos);
93 if (ret) {
94 mlog_errno(ret);
95 goto out;
96 }
97
98 el = path_leaf_el(path);
99
100 index = ocfs2_search_extent_list(el, cpos);
101 if (index == -1 || index >= le16_to_cpu(el->l_next_free_rec)) {
102 ocfs2_error(inode->i_sb,
103 "Inode %llu has an extent at cpos %u which can no "
104 "longer be found.\n",
105 (unsigned long long)ino, cpos);
106 ret = -EROFS;
107 goto out;
108 }
109
110 rec = &el->l_recs[index];
111
112 BUG_ON(ext_flags != rec->e_flags);
113 /*
114 * after moving/defraging to new location, the extent is not going
115 * to be refcounted anymore.
116 */
117 replace_rec.e_flags = ext_flags & ~OCFS2_EXT_REFCOUNTED;
118
119 ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode),
120 context->et.et_root_bh,
121 OCFS2_JOURNAL_ACCESS_WRITE);
122 if (ret) {
123 mlog_errno(ret);
124 goto out;
125 }
126
127 ret = ocfs2_split_extent(handle, &context->et, path, index,
128 &replace_rec, context->meta_ac,
129 &context->dealloc);
130 if (ret) {
131 mlog_errno(ret);
132 goto out;
133 }
134
135 ocfs2_journal_dirty(handle, context->et.et_root_bh);
136
137 context->new_phys_cpos = new_p_cpos;
138
139 /*
140 * need I to append truncate log for old clusters?
141 */
142 if (old_blkno) {
143 if (ext_flags & OCFS2_EXT_REFCOUNTED)
144 ret = ocfs2_decrease_refcount(inode, handle,
145 ocfs2_blocks_to_clusters(osb->sb,
146 old_blkno),
147 len, context->meta_ac,
148 &context->dealloc, 1);
149 else
150 ret = ocfs2_truncate_log_append(osb, handle,
151 old_blkno, len);
152 }
153
154out:
155 return ret;
156}
157
158/*
159 * lock allocators, and reserving appropriate number of bits for
160 * meta blocks and data clusters.
161 *
162 * in some cases, we don't need to reserve clusters, just let data_ac
163 * be NULL.
164 */
165static int ocfs2_lock_allocators_move_extents(struct inode *inode,
166 struct ocfs2_extent_tree *et,
167 u32 clusters_to_move,
168 u32 extents_to_split,
169 struct ocfs2_alloc_context **meta_ac,
170 struct ocfs2_alloc_context **data_ac,
171 int extra_blocks,
172 int *credits)
173{
174 int ret, num_free_extents;
175 unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
176 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
177
178 num_free_extents = ocfs2_num_free_extents(osb, et);
179 if (num_free_extents < 0) {
180 ret = num_free_extents;
181 mlog_errno(ret);
182 goto out;
183 }
184
185 if (!num_free_extents ||
186 (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
187 extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
188
189 ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
190 if (ret) {
191 mlog_errno(ret);
192 goto out;
193 }
194
195 if (data_ac) {
196 ret = ocfs2_reserve_clusters(osb, clusters_to_move, data_ac);
197 if (ret) {
198 mlog_errno(ret);
199 goto out;
200 }
201 }
202
203 *credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el,
204 clusters_to_move + 2);
205
206 mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
207 extra_blocks, clusters_to_move, *credits);
208out:
209 if (ret) {
210 if (*meta_ac) {
211 ocfs2_free_alloc_context(*meta_ac);
212 *meta_ac = NULL;
213 }
214 }
215
216 return ret;
217}
218
219/*
220 * Using one journal handle to guarantee the data consistency in case
221 * crash happens anywhere.
222 *
223 * XXX: defrag can end up with finishing partial extent as requested,
224 * due to not enough contiguous clusters can be found in allocator.
225 */
226static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
227 u32 cpos, u32 phys_cpos, u32 *len, int ext_flags)
228{
229 int ret, credits = 0, extra_blocks = 0, partial = context->partial;
230 handle_t *handle;
231 struct inode *inode = context->inode;
232 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
233 struct inode *tl_inode = osb->osb_tl_inode;
234 struct ocfs2_refcount_tree *ref_tree = NULL;
235 u32 new_phys_cpos, new_len;
236 u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
237
238 if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
239
240 BUG_ON(!(OCFS2_I(inode)->ip_dyn_features &
241 OCFS2_HAS_REFCOUNT_FL));
242
243 BUG_ON(!context->refcount_loc);
244
245 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
246 &ref_tree, NULL);
247 if (ret) {
248 mlog_errno(ret);
249 return ret;
250 }
251
252 ret = ocfs2_prepare_refcount_change_for_del(inode,
253 context->refcount_loc,
254 phys_blkno,
255 *len,
256 &credits,
257 &extra_blocks);
258 if (ret) {
259 mlog_errno(ret);
260 goto out;
261 }
262 }
263
264 ret = ocfs2_lock_allocators_move_extents(inode, &context->et, *len, 1,
265 &context->meta_ac,
266 &context->data_ac,
267 extra_blocks, &credits);
268 if (ret) {
269 mlog_errno(ret);
270 goto out;
271 }
272
273 /*
274 * should be using allocation reservation strategy there?
275 *
276 * if (context->data_ac)
277 * context->data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
278 */
279
280 mutex_lock(&tl_inode->i_mutex);
281
282 if (ocfs2_truncate_log_needs_flush(osb)) {
283 ret = __ocfs2_flush_truncate_log(osb);
284 if (ret < 0) {
285 mlog_errno(ret);
286 goto out_unlock_mutex;
287 }
288 }
289
290 handle = ocfs2_start_trans(osb, credits);
291 if (IS_ERR(handle)) {
292 ret = PTR_ERR(handle);
293 mlog_errno(ret);
294 goto out_unlock_mutex;
295 }
296
297 ret = __ocfs2_claim_clusters(handle, context->data_ac, 1, *len,
298 &new_phys_cpos, &new_len);
299 if (ret) {
300 mlog_errno(ret);
301 goto out_commit;
302 }
303
304 /*
305 * allowing partial extent moving is kind of 'pros and cons', it makes
306 * whole defragmentation less likely to fail, on the contrary, the bad
307 * thing is it may make the fs even more fragmented after moving, let
308 * userspace make a good decision here.
309 */
310 if (new_len != *len) {
311 mlog(0, "len_claimed: %u, len: %u\n", new_len, *len);
312 if (!partial) {
313 context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
314 ret = -ENOSPC;
315 goto out_commit;
316 }
317 }
318
319 mlog(0, "cpos: %u, phys_cpos: %u, new_phys_cpos: %u\n", cpos,
320 phys_cpos, new_phys_cpos);
321
322 ret = __ocfs2_move_extent(handle, context, cpos, new_len, phys_cpos,
323 new_phys_cpos, ext_flags);
324 if (ret)
325 mlog_errno(ret);
326
327 if (partial && (new_len != *len))
328 *len = new_len;
329
330 /*
331 * Here we should write the new page out first if we are
332 * in write-back mode.
333 */
334 ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, *len);
335 if (ret)
336 mlog_errno(ret);
337
338out_commit:
339 ocfs2_commit_trans(osb, handle);
340
341out_unlock_mutex:
342 mutex_unlock(&tl_inode->i_mutex);
343
344 if (context->data_ac) {
345 ocfs2_free_alloc_context(context->data_ac);
346 context->data_ac = NULL;
347 }
348
349 if (context->meta_ac) {
350 ocfs2_free_alloc_context(context->meta_ac);
351 context->meta_ac = NULL;
352 }
353
354out:
355 if (ref_tree)
356 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
357
358 return ret;
359}
360
361/*
362 * find the victim alloc group, where #blkno fits.
363 */
364static int ocfs2_find_victim_alloc_group(struct inode *inode,
365 u64 vict_blkno,
366 int type, int slot,
367 int *vict_bit,
368 struct buffer_head **ret_bh)
369{
370 int ret, i, bits_per_unit = 0;
371 u64 blkno;
372 char namebuf[40];
373
374 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
375 struct buffer_head *ac_bh = NULL, *gd_bh = NULL;
376 struct ocfs2_chain_list *cl;
377 struct ocfs2_chain_rec *rec;
378 struct ocfs2_dinode *ac_dinode;
379 struct ocfs2_group_desc *bg;
380
381 ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type, slot);
382 ret = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
383 strlen(namebuf), &blkno);
384 if (ret) {
385 ret = -ENOENT;
386 goto out;
387 }
388
389 ret = ocfs2_read_blocks_sync(osb, blkno, 1, &ac_bh);
390 if (ret) {
391 mlog_errno(ret);
392 goto out;
393 }
394
395 ac_dinode = (struct ocfs2_dinode *)ac_bh->b_data;
396 cl = &(ac_dinode->id2.i_chain);
397 rec = &(cl->cl_recs[0]);
398
399 if (type == GLOBAL_BITMAP_SYSTEM_INODE)
400 bits_per_unit = osb->s_clustersize_bits -
401 inode->i_sb->s_blocksize_bits;
402 /*
403 * 'vict_blkno' was out of the valid range.
404 */
405 if ((vict_blkno < le64_to_cpu(rec->c_blkno)) ||
406 (vict_blkno >= (le32_to_cpu(ac_dinode->id1.bitmap1.i_total) <<
407 bits_per_unit))) {
408 ret = -EINVAL;
409 goto out;
410 }
411
412 for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
413
414 rec = &(cl->cl_recs[i]);
415 if (!rec)
416 continue;
417
418 bg = NULL;
419
420 do {
421 if (!bg)
422 blkno = le64_to_cpu(rec->c_blkno);
423 else
424 blkno = le64_to_cpu(bg->bg_next_group);
425
426 if (gd_bh) {
427 brelse(gd_bh);
428 gd_bh = NULL;
429 }
430
431 ret = ocfs2_read_blocks_sync(osb, blkno, 1, &gd_bh);
432 if (ret) {
433 mlog_errno(ret);
434 goto out;
435 }
436
437 bg = (struct ocfs2_group_desc *)gd_bh->b_data;
438
439 if (vict_blkno < (le64_to_cpu(bg->bg_blkno) +
440 le16_to_cpu(bg->bg_bits))) {
441
442 *ret_bh = gd_bh;
443 *vict_bit = (vict_blkno - blkno) >>
444 bits_per_unit;
445 mlog(0, "find the victim group: #%llu, "
446 "total_bits: %u, vict_bit: %u\n",
447 blkno, le16_to_cpu(bg->bg_bits),
448 *vict_bit);
449 goto out;
450 }
451
452 } while (le64_to_cpu(bg->bg_next_group));
453 }
454
455 ret = -EINVAL;
456out:
457 brelse(ac_bh);
458
459 /*
460 * caller has to release the gd_bh properly.
461 */
462 return ret;
463}
464
465/*
466 * XXX: helper to validate and adjust moving goal.
467 */
468static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
469 struct ocfs2_move_extents *range)
470{
471 int ret, goal_bit = 0;
472
473 struct buffer_head *gd_bh = NULL;
474 struct ocfs2_group_desc *bg = NULL;
475 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
476 int c_to_b = 1 << (osb->s_clustersize_bits -
477 inode->i_sb->s_blocksize_bits);
478
479 /*
480 * make goal become cluster aligned.
481 */
482 range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
483 range->me_goal);
484 /*
485 * moving goal is not allowd to start with a group desc blok(#0 blk)
486 * let's compromise to the latter cluster.
487 */
488 if (range->me_goal == le64_to_cpu(bg->bg_blkno))
489 range->me_goal += c_to_b;
490
491 /*
492 * validate goal sits within global_bitmap, and return the victim
493 * group desc
494 */
495 ret = ocfs2_find_victim_alloc_group(inode, range->me_goal,
496 GLOBAL_BITMAP_SYSTEM_INODE,
497 OCFS2_INVALID_SLOT,
498 &goal_bit, &gd_bh);
499 if (ret)
500 goto out;
501
502 bg = (struct ocfs2_group_desc *)gd_bh->b_data;
503
504 /*
505 * movement is not gonna cross two groups.
506 */
507 if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <
508 range->me_len) {
509 ret = -EINVAL;
510 goto out;
511 }
512 /*
513 * more exact validations/adjustments will be performed later during
514 * moving operation for each extent range.
515 */
516 mlog(0, "extents get ready to be moved to #%llu block\n",
517 range->me_goal);
518
519out:
520 brelse(gd_bh);
521
522 return ret;
523}
524
525static void ocfs2_probe_alloc_group(struct inode *inode, struct buffer_head *bh,
526 int *goal_bit, u32 move_len, u32 max_hop,
527 u32 *phys_cpos)
528{
529 int i, used, last_free_bits = 0, base_bit = *goal_bit;
530 struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
531 u32 base_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
532 le64_to_cpu(gd->bg_blkno));
533
534 for (i = base_bit; i < le16_to_cpu(gd->bg_bits); i++) {
535
536 used = ocfs2_test_bit(i, (unsigned long *)gd->bg_bitmap);
537 if (used) {
538 /*
539 * we even tried searching the free chunk by jumping
540 * a 'max_hop' distance, but still failed.
541 */
542 if ((i - base_bit) > max_hop) {
543 *phys_cpos = 0;
544 break;
545 }
546
547 if (last_free_bits)
548 last_free_bits = 0;
549
550 continue;
551 } else
552 last_free_bits++;
553
554 if (last_free_bits == move_len) {
555 *goal_bit = i;
556 *phys_cpos = base_cpos + i;
557 break;
558 }
559 }
560
561 mlog(0, "found phys_cpos: %u to fit the wanted moving.\n", *phys_cpos);
562}
563
564static int ocfs2_alloc_dinode_update_counts(struct inode *inode,
565 handle_t *handle,
566 struct buffer_head *di_bh,
567 u32 num_bits,
568 u16 chain)
569{
570 int ret;
571 u32 tmp_used;
572 struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
573 struct ocfs2_chain_list *cl =
574 (struct ocfs2_chain_list *) &di->id2.i_chain;
575
576 ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
577 OCFS2_JOURNAL_ACCESS_WRITE);
578 if (ret < 0) {
579 mlog_errno(ret);
580 goto out;
581 }
582
583 tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
584 di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
585 le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
586 ocfs2_journal_dirty(handle, di_bh);
587
588out:
589 return ret;
590}
591
592static inline int ocfs2_block_group_set_bits(handle_t *handle,
593 struct inode *alloc_inode,
594 struct ocfs2_group_desc *bg,
595 struct buffer_head *group_bh,
596 unsigned int bit_off,
597 unsigned int num_bits)
598{
599 int status;
600 void *bitmap = bg->bg_bitmap;
601 int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
602
603 /* All callers get the descriptor via
604 * ocfs2_read_group_descriptor(). Any corruption is a code bug. */
605 BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
606 BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
607
608 mlog(0, "block_group_set_bits: off = %u, num = %u\n", bit_off,
609 num_bits);
610
611 if (ocfs2_is_cluster_bitmap(alloc_inode))
612 journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
613
614 status = ocfs2_journal_access_gd(handle,
615 INODE_CACHE(alloc_inode),
616 group_bh,
617 journal_type);
618 if (status < 0) {
619 mlog_errno(status);
620 goto bail;
621 }
622
623 le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
624 if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
625 ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit"
626 " count %u but claims %u are freed. num_bits %d",
627 (unsigned long long)le64_to_cpu(bg->bg_blkno),
628 le16_to_cpu(bg->bg_bits),
629 le16_to_cpu(bg->bg_free_bits_count), num_bits);
630 return -EROFS;
631 }
632 while (num_bits--)
633 ocfs2_set_bit(bit_off++, bitmap);
634
635 ocfs2_journal_dirty(handle, group_bh);
636
637bail:
638 return status;
639}
640
641static int ocfs2_move_extent(struct ocfs2_move_extents_context *context,
642 u32 cpos, u32 phys_cpos, u32 *new_phys_cpos,
643 u32 len, int ext_flags)
644{
645 int ret, credits = 0, extra_blocks = 0, goal_bit = 0;
646 handle_t *handle;
647 struct inode *inode = context->inode;
648 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
649 struct inode *tl_inode = osb->osb_tl_inode;
650 struct inode *gb_inode = NULL;
651 struct buffer_head *gb_bh = NULL;
652 struct buffer_head *gd_bh = NULL;
653 struct ocfs2_group_desc *gd;
654 struct ocfs2_refcount_tree *ref_tree = NULL;
655 u32 move_max_hop = ocfs2_blocks_to_clusters(inode->i_sb,
656 context->range->me_threshold);
657 u64 phys_blkno, new_phys_blkno;
658
659 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
660
661 if ((ext_flags & OCFS2_EXT_REFCOUNTED) && len) {
662
663 BUG_ON(!(OCFS2_I(inode)->ip_dyn_features &
664 OCFS2_HAS_REFCOUNT_FL));
665
666 BUG_ON(!context->refcount_loc);
667
668 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
669 &ref_tree, NULL);
670 if (ret) {
671 mlog_errno(ret);
672 return ret;
673 }
674
675 ret = ocfs2_prepare_refcount_change_for_del(inode,
676 context->refcount_loc,
677 phys_blkno,
678 len,
679 &credits,
680 &extra_blocks);
681 if (ret) {
682 mlog_errno(ret);
683 goto out;
684 }
685 }
686
687 ret = ocfs2_lock_allocators_move_extents(inode, &context->et, len, 1,
688 &context->meta_ac,
689 NULL, extra_blocks, &credits);
690 if (ret) {
691 mlog_errno(ret);
692 goto out;
693 }
694
695 /*
696 * need to count 2 extra credits for global_bitmap inode and
697 * group descriptor.
698 */
699 credits += OCFS2_INODE_UPDATE_CREDITS + 1;
700
701 /*
702 * ocfs2_move_extent() didn't reserve any clusters in lock_allocators()
703 * logic, while we still need to lock the global_bitmap.
704 */
705 gb_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
706 OCFS2_INVALID_SLOT);
707 if (!gb_inode) {
708 mlog(ML_ERROR, "unable to get global_bitmap inode\n");
709 ret = -EIO;
710 goto out;
711 }
712
713 mutex_lock(&gb_inode->i_mutex);
714
715 ret = ocfs2_inode_lock(gb_inode, &gb_bh, 1);
716 if (ret) {
717 mlog_errno(ret);
718 goto out_unlock_gb_mutex;
719 }
720
721 mutex_lock(&tl_inode->i_mutex);
722
723 handle = ocfs2_start_trans(osb, credits);
724 if (IS_ERR(handle)) {
725 ret = PTR_ERR(handle);
726 mlog_errno(ret);
727 goto out_unlock_tl_inode;
728 }
729
730 new_phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *new_phys_cpos);
731 ret = ocfs2_find_victim_alloc_group(inode, new_phys_blkno,
732 GLOBAL_BITMAP_SYSTEM_INODE,
733 OCFS2_INVALID_SLOT,
734 &goal_bit, &gd_bh);
735 if (ret) {
736 mlog_errno(ret);
737 goto out_commit;
738 }
739
740 /*
741 * probe the victim cluster group to find a proper
742 * region to fit wanted movement, it even will perfrom
743 * a best-effort attempt by compromising to a threshold
744 * around the goal.
745 */
746 ocfs2_probe_alloc_group(inode, gd_bh, &goal_bit, len, move_max_hop,
747 new_phys_cpos);
748 if (!*new_phys_cpos) {
749 ret = -ENOSPC;
750 goto out_commit;
751 }
752
753 ret = __ocfs2_move_extent(handle, context, cpos, len, phys_cpos,
754 *new_phys_cpos, ext_flags);
755 if (ret) {
756 mlog_errno(ret);
757 goto out_commit;
758 }
759
760 gd = (struct ocfs2_group_desc *)gd_bh->b_data;
761 ret = ocfs2_alloc_dinode_update_counts(gb_inode, handle, gb_bh, len,
762 le16_to_cpu(gd->bg_chain));
763 if (ret) {
764 mlog_errno(ret);
765 goto out_commit;
766 }
767
768 ret = ocfs2_block_group_set_bits(handle, gb_inode, gd, gd_bh,
769 goal_bit, len);
770 if (ret)
771 mlog_errno(ret);
772
773 /*
774 * Here we should write the new page out first if we are
775 * in write-back mode.
776 */
777 ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, len);
778 if (ret)
779 mlog_errno(ret);
780
781out_commit:
782 ocfs2_commit_trans(osb, handle);
783 brelse(gd_bh);
784
785out_unlock_tl_inode:
786 mutex_unlock(&tl_inode->i_mutex);
787
788 ocfs2_inode_unlock(gb_inode, 1);
789out_unlock_gb_mutex:
790 mutex_unlock(&gb_inode->i_mutex);
791 brelse(gb_bh);
792 iput(gb_inode);
793
794out:
795 if (context->meta_ac) {
796 ocfs2_free_alloc_context(context->meta_ac);
797 context->meta_ac = NULL;
798 }
799
800 if (ref_tree)
801 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
802
803 return ret;
804}
805
806/*
807 * Helper to calculate the defraging length in one run according to threshold.
808 */
809static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
810 u32 threshold, int *skip)
811{
812 if ((*alloc_size + *len_defraged) < threshold) {
813 /*
814 * proceed defragmentation until we meet the thresh
815 */
816 *len_defraged += *alloc_size;
817 } else if (*len_defraged == 0) {
818 /*
819 * XXX: skip a large extent.
820 */
821 *skip = 1;
822 } else {
823 /*
824 * split this extent to coalesce with former pieces as
825 * to reach the threshold.
826 *
827 * we're done here with one cycle of defragmentation
828 * in a size of 'thresh', resetting 'len_defraged'
829 * forces a new defragmentation.
830 */
831 *alloc_size = threshold - *len_defraged;
832 *len_defraged = 0;
833 }
834}
835
836static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
837 struct ocfs2_move_extents_context *context)
838{
839 int ret = 0, flags, do_defrag, skip = 0;
840 u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
841 u32 len_defraged = 0, defrag_thresh = 0, new_phys_cpos = 0;
842
843 struct inode *inode = context->inode;
844 struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
845 struct ocfs2_move_extents *range = context->range;
846 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
847
848 if ((inode->i_size == 0) || (range->me_len == 0))
849 return 0;
850
851 if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
852 return 0;
853
854 context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
855
856 ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
857 ocfs2_init_dealloc_ctxt(&context->dealloc);
858
859 /*
860 * TO-DO XXX:
861 *
862 * - xattr extents.
863 */
864
865 do_defrag = context->auto_defrag;
866
867 /*
868 * extents moving happens in unit of clusters, for the sake
869 * of simplicity, we may ignore two clusters where 'byte_start'
870 * and 'byte_start + len' were within.
871 */
872 move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
873 len_to_move = (range->me_start + range->me_len) >>
874 osb->s_clustersize_bits;
875 if (len_to_move >= move_start)
876 len_to_move -= move_start;
877 else
878 len_to_move = 0;
879
880 if (do_defrag) {
881 defrag_thresh = range->me_threshold >> osb->s_clustersize_bits;
882 if (defrag_thresh <= 1)
883 goto done;
884 } else
885 new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
886 range->me_goal);
887
888 mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
889 "thresh: %u\n",
890 (unsigned long long)OCFS2_I(inode)->ip_blkno,
891 (unsigned long long)range->me_start,
892 (unsigned long long)range->me_len,
893 move_start, len_to_move, defrag_thresh);
894
895 cpos = move_start;
896 while (len_to_move) {
897 ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
898 &flags);
899 if (ret) {
900 mlog_errno(ret);
901 goto out;
902 }
903
904 if (alloc_size > len_to_move)
905 alloc_size = len_to_move;
906
907 /*
908 * XXX: how to deal with a hole:
909 *
910 * - skip the hole of course
911 * - force a new defragmentation
912 */
913 if (!phys_cpos) {
914 if (do_defrag)
915 len_defraged = 0;
916
917 goto next;
918 }
919
920 if (do_defrag) {
921 ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
922 defrag_thresh, &skip);
923 /*
924 * skip large extents
925 */
926 if (skip) {
927 skip = 0;
928 goto next;
929 }
930
931 mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
932 "alloc_size: %u, len_defraged: %u\n",
933 cpos, phys_cpos, alloc_size, len_defraged);
934
935 ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
936 &alloc_size, flags);
937 } else {
938 ret = ocfs2_move_extent(context, cpos, phys_cpos,
939 &new_phys_cpos, alloc_size,
940 flags);
941
942 new_phys_cpos += alloc_size;
943 }
944
945 if (ret < 0) {
946 mlog_errno(ret);
947 goto out;
948 }
949
950 context->clusters_moved += alloc_size;
951next:
952 cpos += alloc_size;
953 len_to_move -= alloc_size;
954 }
955
956done:
957 range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
958
959out:
960 range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
961 context->clusters_moved);
962 range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
963 context->new_phys_cpos);
964
965 ocfs2_schedule_truncate_log_flush(osb, 1);
966 ocfs2_run_deallocs(osb, &context->dealloc);
967
968 return ret;
969}
970
971static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
972{
973 int status;
974 handle_t *handle;
975 struct inode *inode = context->inode;
976 struct ocfs2_dinode *di;
977 struct buffer_head *di_bh = NULL;
978 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
979
980 if (!inode)
981 return -ENOENT;
982
983 if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
984 return -EROFS;
985
986 mutex_lock(&inode->i_mutex);
987
988 /*
989 * This prevents concurrent writes from other nodes
990 */
991 status = ocfs2_rw_lock(inode, 1);
992 if (status) {
993 mlog_errno(status);
994 goto out;
995 }
996
997 status = ocfs2_inode_lock(inode, &di_bh, 1);
998 if (status) {
999 mlog_errno(status);
1000 goto out_rw_unlock;
1001 }
1002
1003 /*
1004 * rememer ip_xattr_sem also needs to be held if necessary
1005 */
1006 down_write(&OCFS2_I(inode)->ip_alloc_sem);
1007
1008 status = __ocfs2_move_extents_range(di_bh, context);
1009
1010 up_write(&OCFS2_I(inode)->ip_alloc_sem);
1011 if (status) {
1012 mlog_errno(status);
1013 goto out_inode_unlock;
1014 }
1015
1016 /*
1017 * We update ctime for these changes
1018 */
1019 handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
1020 if (IS_ERR(handle)) {
1021 status = PTR_ERR(handle);
1022 mlog_errno(status);
1023 goto out_inode_unlock;
1024 }
1025
1026 status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
1027 OCFS2_JOURNAL_ACCESS_WRITE);
1028 if (status) {
1029 mlog_errno(status);
1030 goto out_commit;
1031 }
1032
1033 di = (struct ocfs2_dinode *)di_bh->b_data;
1034 inode->i_ctime = CURRENT_TIME;
1035 di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
1036 di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
1037
1038 ocfs2_journal_dirty(handle, di_bh);
1039
1040out_commit:
1041 ocfs2_commit_trans(osb, handle);
1042
1043out_inode_unlock:
1044 brelse(di_bh);
1045 ocfs2_inode_unlock(inode, 1);
1046out_rw_unlock:
1047 ocfs2_rw_unlock(inode, 1);
1048out:
1049 mutex_unlock(&inode->i_mutex);
1050
1051 return status;
1052}
1053
1054int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
1055{
1056 int status;
1057
1058 struct inode *inode = filp->f_path.dentry->d_inode;
1059 struct ocfs2_move_extents range;
1060 struct ocfs2_move_extents_context *context = NULL;
1061
1062 status = mnt_want_write_file(filp);
1063 if (status)
1064 return status;
1065
1066 if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE))
1067 goto out;
1068
1069 if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
1070 status = -EPERM;
1071 goto out;
1072 }
1073
1074 context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
1075 if (!context) {
1076 status = -ENOMEM;
1077 mlog_errno(status);
1078 goto out;
1079 }
1080
1081 context->inode = inode;
1082 context->file = filp;
1083
1084 if (argp) {
1085 if (copy_from_user(&range, argp, sizeof(range))) {
1086 status = -EFAULT;
1087 goto out;
1088 }
1089 } else {
1090 status = -EINVAL;
1091 goto out;
1092 }
1093
1094 if (range.me_start > i_size_read(inode))
1095 goto out;
1096
1097 if (range.me_start + range.me_len > i_size_read(inode))
1098 range.me_len = i_size_read(inode) - range.me_start;
1099
1100 context->range = ⦥
1101
1102 if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
1103 context->auto_defrag = 1;
1104 /*
1105 * ok, the default theshold for the defragmentation
1106 * is 1M, since our maximum clustersize was 1M also.
1107 * any thought?
1108 */
1109 if (!range.me_threshold)
1110 range.me_threshold = 1024 * 1024;
1111
1112 if (range.me_threshold > i_size_read(inode))
1113 range.me_threshold = i_size_read(inode);
1114
1115 if (range.me_flags & OCFS2_MOVE_EXT_FL_PART_DEFRAG)
1116 context->partial = 1;
1117 } else {
1118 /*
1119 * first best-effort attempt to validate and adjust the goal
1120 * (physical address in block), while it can't guarantee later
1121 * operation can succeed all the time since global_bitmap may
1122 * change a bit over time.
1123 */
1124
1125 status = ocfs2_validate_and_adjust_move_goal(inode, &range);
1126 if (status)
1127 goto out;
1128 }
1129
1130 status = ocfs2_move_extents(context);
1131 if (status)
1132 mlog_errno(status);
1133out:
1134 /*
1135 * movement/defragmentation may end up being partially completed,
1136 * that's the reason why we need to return userspace the finished
1137 * length and new_offset even if failure happens somewhere.
1138 */
1139 if (argp) {
1140 if (copy_to_user(argp, &range, sizeof(range)))
1141 status = -EFAULT;
1142 }
1143
1144 kfree(context);
1145
1146 mnt_drop_write_file(filp);
1147
1148 return status;
1149}