GNU Linux-libre 5.10.219-gnu1
[releases.git] / fs / ocfs2 / move_extents.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* -*- mode: c; c-basic-offset: 8; -*-
3  * vim: noexpandtab sw=8 ts=8 sts=0:
4  *
5  * move_extents.c
6  *
7  * Copyright (C) 2011 Oracle.  All rights reserved.
8  */
9 #include <linux/fs.h>
10 #include <linux/types.h>
11 #include <linux/mount.h>
12 #include <linux/swap.h>
13
14 #include <cluster/masklog.h>
15
16 #include "ocfs2.h"
17 #include "ocfs2_ioctl.h"
18
19 #include "alloc.h"
20 #include "localalloc.h"
21 #include "aops.h"
22 #include "dlmglue.h"
23 #include "extent_map.h"
24 #include "inode.h"
25 #include "journal.h"
26 #include "suballoc.h"
27 #include "uptodate.h"
28 #include "super.h"
29 #include "dir.h"
30 #include "buffer_head_io.h"
31 #include "sysfile.h"
32 #include "refcounttree.h"
33 #include "move_extents.h"
34
35 struct ocfs2_move_extents_context {
36         struct inode *inode;
37         struct file *file;
38         int auto_defrag;
39         int partial;
40         int credits;
41         u32 new_phys_cpos;
42         u32 clusters_moved;
43         u64 refcount_loc;
44         struct ocfs2_move_extents *range;
45         struct ocfs2_extent_tree et;
46         struct ocfs2_alloc_context *meta_ac;
47         struct ocfs2_alloc_context *data_ac;
48         struct ocfs2_cached_dealloc_ctxt dealloc;
49 };
50
51 static int __ocfs2_move_extent(handle_t *handle,
52                                struct ocfs2_move_extents_context *context,
53                                u32 cpos, u32 len, u32 p_cpos, u32 new_p_cpos,
54                                int ext_flags)
55 {
56         int ret = 0, index;
57         struct inode *inode = context->inode;
58         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
59         struct ocfs2_extent_rec *rec, replace_rec;
60         struct ocfs2_path *path = NULL;
61         struct ocfs2_extent_list *el;
62         u64 ino = ocfs2_metadata_cache_owner(context->et.et_ci);
63         u64 old_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cpos);
64
65         ret = ocfs2_duplicate_clusters_by_page(handle, inode, cpos,
66                                                p_cpos, new_p_cpos, len);
67         if (ret) {
68                 mlog_errno(ret);
69                 goto out;
70         }
71
72         memset(&replace_rec, 0, sizeof(replace_rec));
73         replace_rec.e_cpos = cpu_to_le32(cpos);
74         replace_rec.e_leaf_clusters = cpu_to_le16(len);
75         replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
76                                                                    new_p_cpos));
77
78         path = ocfs2_new_path_from_et(&context->et);
79         if (!path) {
80                 ret = -ENOMEM;
81                 mlog_errno(ret);
82                 goto out;
83         }
84
85         ret = ocfs2_find_path(INODE_CACHE(inode), path, cpos);
86         if (ret) {
87                 mlog_errno(ret);
88                 goto out;
89         }
90
91         el = path_leaf_el(path);
92
93         index = ocfs2_search_extent_list(el, cpos);
94         if (index == -1) {
95                 ret = ocfs2_error(inode->i_sb,
96                                   "Inode %llu has an extent at cpos %u which can no longer be found\n",
97                                   (unsigned long long)ino, cpos);
98                 goto out;
99         }
100
101         rec = &el->l_recs[index];
102
103         BUG_ON(ext_flags != rec->e_flags);
104         /*
105          * after moving/defraging to new location, the extent is not going
106          * to be refcounted anymore.
107          */
108         replace_rec.e_flags = ext_flags & ~OCFS2_EXT_REFCOUNTED;
109
110         ret = ocfs2_split_extent(handle, &context->et, path, index,
111                                  &replace_rec, context->meta_ac,
112                                  &context->dealloc);
113         if (ret) {
114                 mlog_errno(ret);
115                 goto out;
116         }
117
118         context->new_phys_cpos = new_p_cpos;
119
120         /*
121          * need I to append truncate log for old clusters?
122          */
123         if (old_blkno) {
124                 if (ext_flags & OCFS2_EXT_REFCOUNTED)
125                         ret = ocfs2_decrease_refcount(inode, handle,
126                                         ocfs2_blocks_to_clusters(osb->sb,
127                                                                  old_blkno),
128                                         len, context->meta_ac,
129                                         &context->dealloc, 1);
130                 else
131                         ret = ocfs2_truncate_log_append(osb, handle,
132                                                         old_blkno, len);
133         }
134
135         ocfs2_update_inode_fsync_trans(handle, inode, 0);
136 out:
137         ocfs2_free_path(path);
138         return ret;
139 }
140
141 /*
142  * lock allocator, and reserve appropriate number of bits for
143  * meta blocks.
144  */
145 static int ocfs2_lock_meta_allocator_move_extents(struct inode *inode,
146                                         struct ocfs2_extent_tree *et,
147                                         u32 clusters_to_move,
148                                         u32 extents_to_split,
149                                         struct ocfs2_alloc_context **meta_ac,
150                                         int extra_blocks,
151                                         int *credits)
152 {
153         int ret, num_free_extents;
154         unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
155         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
156
157         num_free_extents = ocfs2_num_free_extents(et);
158         if (num_free_extents < 0) {
159                 ret = num_free_extents;
160                 mlog_errno(ret);
161                 goto out;
162         }
163
164         if (!num_free_extents ||
165             (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
166                 extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
167
168         ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
169         if (ret) {
170                 mlog_errno(ret);
171                 goto out;
172         }
173
174
175         *credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el);
176
177         mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
178              extra_blocks, clusters_to_move, *credits);
179 out:
180         if (ret) {
181                 if (*meta_ac) {
182                         ocfs2_free_alloc_context(*meta_ac);
183                         *meta_ac = NULL;
184                 }
185         }
186
187         return ret;
188 }
189
190 /*
191  * Using one journal handle to guarantee the data consistency in case
192  * crash happens anywhere.
193  *
194  *  XXX: defrag can end up with finishing partial extent as requested,
195  * due to not enough contiguous clusters can be found in allocator.
196  */
197 static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
198                                u32 cpos, u32 phys_cpos, u32 *len, int ext_flags)
199 {
200         int ret, credits = 0, extra_blocks = 0, partial = context->partial;
201         handle_t *handle;
202         struct inode *inode = context->inode;
203         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
204         struct inode *tl_inode = osb->osb_tl_inode;
205         struct ocfs2_refcount_tree *ref_tree = NULL;
206         u32 new_phys_cpos, new_len;
207         u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
208         int need_free = 0;
209
210         if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
211                 BUG_ON(!ocfs2_is_refcount_inode(inode));
212                 BUG_ON(!context->refcount_loc);
213
214                 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
215                                                &ref_tree, NULL);
216                 if (ret) {
217                         mlog_errno(ret);
218                         return ret;
219                 }
220
221                 ret = ocfs2_prepare_refcount_change_for_del(inode,
222                                                         context->refcount_loc,
223                                                         phys_blkno,
224                                                         *len,
225                                                         &credits,
226                                                         &extra_blocks);
227                 if (ret) {
228                         mlog_errno(ret);
229                         goto out;
230                 }
231         }
232
233         ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
234                                                 *len, 1,
235                                                 &context->meta_ac,
236                                                 extra_blocks, &credits);
237         if (ret) {
238                 mlog_errno(ret);
239                 goto out;
240         }
241
242         /*
243          * should be using allocation reservation strategy there?
244          *
245          * if (context->data_ac)
246          *      context->data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
247          */
248
249         inode_lock(tl_inode);
250
251         if (ocfs2_truncate_log_needs_flush(osb)) {
252                 ret = __ocfs2_flush_truncate_log(osb);
253                 if (ret < 0) {
254                         mlog_errno(ret);
255                         goto out_unlock_mutex;
256                 }
257         }
258
259         /*
260          * Make sure ocfs2_reserve_cluster is called after
261          * __ocfs2_flush_truncate_log, otherwise, dead lock may happen.
262          *
263          * If ocfs2_reserve_cluster is called
264          * before __ocfs2_flush_truncate_log, dead lock on global bitmap
265          * may happen.
266          *
267          */
268         ret = ocfs2_reserve_clusters(osb, *len, &context->data_ac);
269         if (ret) {
270                 mlog_errno(ret);
271                 goto out_unlock_mutex;
272         }
273
274         handle = ocfs2_start_trans(osb, credits);
275         if (IS_ERR(handle)) {
276                 ret = PTR_ERR(handle);
277                 mlog_errno(ret);
278                 goto out_unlock_mutex;
279         }
280
281         ret = __ocfs2_claim_clusters(handle, context->data_ac, 1, *len,
282                                      &new_phys_cpos, &new_len);
283         if (ret) {
284                 mlog_errno(ret);
285                 goto out_commit;
286         }
287
288         /*
289          * allowing partial extent moving is kind of 'pros and cons', it makes
290          * whole defragmentation less likely to fail, on the contrary, the bad
291          * thing is it may make the fs even more fragmented after moving, let
292          * userspace make a good decision here.
293          */
294         if (new_len != *len) {
295                 mlog(0, "len_claimed: %u, len: %u\n", new_len, *len);
296                 if (!partial) {
297                         context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
298                         ret = -ENOSPC;
299                         need_free = 1;
300                         goto out_commit;
301                 }
302         }
303
304         mlog(0, "cpos: %u, phys_cpos: %u, new_phys_cpos: %u\n", cpos,
305              phys_cpos, new_phys_cpos);
306
307         ret = __ocfs2_move_extent(handle, context, cpos, new_len, phys_cpos,
308                                   new_phys_cpos, ext_flags);
309         if (ret)
310                 mlog_errno(ret);
311
312         if (partial && (new_len != *len))
313                 *len = new_len;
314
315         /*
316          * Here we should write the new page out first if we are
317          * in write-back mode.
318          */
319         ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, *len);
320         if (ret)
321                 mlog_errno(ret);
322
323 out_commit:
324         if (need_free && context->data_ac) {
325                 struct ocfs2_alloc_context *data_ac = context->data_ac;
326
327                 if (context->data_ac->ac_which == OCFS2_AC_USE_LOCAL)
328                         ocfs2_free_local_alloc_bits(osb, handle, data_ac,
329                                         new_phys_cpos, new_len);
330                 else
331                         ocfs2_free_clusters(handle,
332                                         data_ac->ac_inode,
333                                         data_ac->ac_bh,
334                                         ocfs2_clusters_to_blocks(osb->sb, new_phys_cpos),
335                                         new_len);
336         }
337
338         ocfs2_commit_trans(osb, handle);
339
340 out_unlock_mutex:
341         inode_unlock(tl_inode);
342
343         if (context->data_ac) {
344                 ocfs2_free_alloc_context(context->data_ac);
345                 context->data_ac = NULL;
346         }
347
348         if (context->meta_ac) {
349                 ocfs2_free_alloc_context(context->meta_ac);
350                 context->meta_ac = NULL;
351         }
352
353 out:
354         if (ref_tree)
355                 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
356
357         return ret;
358 }
359
360 /*
361  * find the victim alloc group, where #blkno fits.
362  */
363 static int ocfs2_find_victim_alloc_group(struct inode *inode,
364                                          u64 vict_blkno,
365                                          int type, int slot,
366                                          int *vict_bit,
367                                          struct buffer_head **ret_bh)
368 {
369         int ret, i, bits_per_unit = 0;
370         u64 blkno;
371         char namebuf[40];
372
373         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
374         struct buffer_head *ac_bh = NULL, *gd_bh = NULL;
375         struct ocfs2_chain_list *cl;
376         struct ocfs2_chain_rec *rec;
377         struct ocfs2_dinode *ac_dinode;
378         struct ocfs2_group_desc *bg;
379
380         ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type, slot);
381         ret = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
382                                          strlen(namebuf), &blkno);
383         if (ret) {
384                 ret = -ENOENT;
385                 goto out;
386         }
387
388         ret = ocfs2_read_blocks_sync(osb, blkno, 1, &ac_bh);
389         if (ret) {
390                 mlog_errno(ret);
391                 goto out;
392         }
393
394         ac_dinode = (struct ocfs2_dinode *)ac_bh->b_data;
395         cl = &(ac_dinode->id2.i_chain);
396         rec = &(cl->cl_recs[0]);
397
398         if (type == GLOBAL_BITMAP_SYSTEM_INODE)
399                 bits_per_unit = osb->s_clustersize_bits -
400                                         inode->i_sb->s_blocksize_bits;
401         /*
402          * 'vict_blkno' was out of the valid range.
403          */
404         if ((vict_blkno < le64_to_cpu(rec->c_blkno)) ||
405             (vict_blkno >= ((u64)le32_to_cpu(ac_dinode->id1.bitmap1.i_total) <<
406                                 bits_per_unit))) {
407                 ret = -EINVAL;
408                 goto out;
409         }
410
411         for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
412
413                 rec = &(cl->cl_recs[i]);
414                 if (!rec)
415                         continue;
416
417                 bg = NULL;
418
419                 do {
420                         if (!bg)
421                                 blkno = le64_to_cpu(rec->c_blkno);
422                         else
423                                 blkno = le64_to_cpu(bg->bg_next_group);
424
425                         if (gd_bh) {
426                                 brelse(gd_bh);
427                                 gd_bh = NULL;
428                         }
429
430                         ret = ocfs2_read_blocks_sync(osb, blkno, 1, &gd_bh);
431                         if (ret) {
432                                 mlog_errno(ret);
433                                 goto out;
434                         }
435
436                         bg = (struct ocfs2_group_desc *)gd_bh->b_data;
437
438                         if (vict_blkno < (le64_to_cpu(bg->bg_blkno) +
439                                                 (le16_to_cpu(bg->bg_bits) << bits_per_unit))) {
440
441                                 *ret_bh = gd_bh;
442                                 *vict_bit = (vict_blkno - blkno) >>
443                                                         bits_per_unit;
444                                 mlog(0, "find the victim group: #%llu, "
445                                      "total_bits: %u, vict_bit: %u\n",
446                                      blkno, le16_to_cpu(bg->bg_bits),
447                                      *vict_bit);
448                                 goto out;
449                         }
450
451                 } while (le64_to_cpu(bg->bg_next_group));
452         }
453
454         ret = -EINVAL;
455 out:
456         brelse(ac_bh);
457
458         /*
459          * caller has to release the gd_bh properly.
460          */
461         return ret;
462 }
463
464 /*
465  * XXX: helper to validate and adjust moving goal.
466  */
467 static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
468                                                struct ocfs2_move_extents *range)
469 {
470         int ret, goal_bit = 0;
471
472         struct buffer_head *gd_bh = NULL;
473         struct ocfs2_group_desc *bg;
474         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
475         int c_to_b = 1 << (osb->s_clustersize_bits -
476                                         inode->i_sb->s_blocksize_bits);
477
478         /*
479          * make goal become cluster aligned.
480          */
481         range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
482                                                       range->me_goal);
483         /*
484          * validate goal sits within global_bitmap, and return the victim
485          * group desc
486          */
487         ret = ocfs2_find_victim_alloc_group(inode, range->me_goal,
488                                             GLOBAL_BITMAP_SYSTEM_INODE,
489                                             OCFS2_INVALID_SLOT,
490                                             &goal_bit, &gd_bh);
491         if (ret)
492                 goto out;
493
494         bg = (struct ocfs2_group_desc *)gd_bh->b_data;
495
496         /*
497          * moving goal is not allowd to start with a group desc blok(#0 blk)
498          * let's compromise to the latter cluster.
499          */
500         if (range->me_goal == le64_to_cpu(bg->bg_blkno))
501                 range->me_goal += c_to_b;
502
503         /*
504          * movement is not gonna cross two groups.
505          */
506         if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <
507                                                                 range->me_len) {
508                 ret = -EINVAL;
509                 goto out;
510         }
511         /*
512          * more exact validations/adjustments will be performed later during
513          * moving operation for each extent range.
514          */
515         mlog(0, "extents get ready to be moved to #%llu block\n",
516              range->me_goal);
517
518 out:
519         brelse(gd_bh);
520
521         return ret;
522 }
523
524 static void ocfs2_probe_alloc_group(struct inode *inode, struct buffer_head *bh,
525                                     int *goal_bit, u32 move_len, u32 max_hop,
526                                     u32 *phys_cpos)
527 {
528         int i, used, last_free_bits = 0, base_bit = *goal_bit;
529         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
530         u32 base_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
531                                                  le64_to_cpu(gd->bg_blkno));
532
533         for (i = base_bit; i < le16_to_cpu(gd->bg_bits); i++) {
534
535                 used = ocfs2_test_bit(i, (unsigned long *)gd->bg_bitmap);
536                 if (used) {
537                         /*
538                          * we even tried searching the free chunk by jumping
539                          * a 'max_hop' distance, but still failed.
540                          */
541                         if ((i - base_bit) > max_hop) {
542                                 *phys_cpos = 0;
543                                 break;
544                         }
545
546                         if (last_free_bits)
547                                 last_free_bits = 0;
548
549                         continue;
550                 } else
551                         last_free_bits++;
552
553                 if (last_free_bits == move_len) {
554                         i -= 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
564 static int ocfs2_move_extent(struct ocfs2_move_extents_context *context,
565                              u32 cpos, u32 phys_cpos, u32 *new_phys_cpos,
566                              u32 len, int ext_flags)
567 {
568         int ret, credits = 0, extra_blocks = 0, goal_bit = 0;
569         handle_t *handle;
570         struct inode *inode = context->inode;
571         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
572         struct inode *tl_inode = osb->osb_tl_inode;
573         struct inode *gb_inode = NULL;
574         struct buffer_head *gb_bh = NULL;
575         struct buffer_head *gd_bh = NULL;
576         struct ocfs2_group_desc *gd;
577         struct ocfs2_refcount_tree *ref_tree = NULL;
578         u32 move_max_hop = ocfs2_blocks_to_clusters(inode->i_sb,
579                                                     context->range->me_threshold);
580         u64 phys_blkno, new_phys_blkno;
581
582         phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
583
584         if ((ext_flags & OCFS2_EXT_REFCOUNTED) && len) {
585                 BUG_ON(!ocfs2_is_refcount_inode(inode));
586                 BUG_ON(!context->refcount_loc);
587
588                 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
589                                                &ref_tree, NULL);
590                 if (ret) {
591                         mlog_errno(ret);
592                         return ret;
593                 }
594
595                 ret = ocfs2_prepare_refcount_change_for_del(inode,
596                                                         context->refcount_loc,
597                                                         phys_blkno,
598                                                         len,
599                                                         &credits,
600                                                         &extra_blocks);
601                 if (ret) {
602                         mlog_errno(ret);
603                         goto out;
604                 }
605         }
606
607         ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
608                                                 len, 1,
609                                                 &context->meta_ac,
610                                                 extra_blocks, &credits);
611         if (ret) {
612                 mlog_errno(ret);
613                 goto out;
614         }
615
616         /*
617          * need to count 2 extra credits for global_bitmap inode and
618          * group descriptor.
619          */
620         credits += OCFS2_INODE_UPDATE_CREDITS + 1;
621
622         /*
623          * ocfs2_move_extent() didn't reserve any clusters in lock_allocators()
624          * logic, while we still need to lock the global_bitmap.
625          */
626         gb_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
627                                                OCFS2_INVALID_SLOT);
628         if (!gb_inode) {
629                 mlog(ML_ERROR, "unable to get global_bitmap inode\n");
630                 ret = -EIO;
631                 goto out;
632         }
633
634         inode_lock(gb_inode);
635
636         ret = ocfs2_inode_lock(gb_inode, &gb_bh, 1);
637         if (ret) {
638                 mlog_errno(ret);
639                 goto out_unlock_gb_mutex;
640         }
641
642         inode_lock(tl_inode);
643
644         handle = ocfs2_start_trans(osb, credits);
645         if (IS_ERR(handle)) {
646                 ret = PTR_ERR(handle);
647                 mlog_errno(ret);
648                 goto out_unlock_tl_inode;
649         }
650
651         new_phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *new_phys_cpos);
652         ret = ocfs2_find_victim_alloc_group(inode, new_phys_blkno,
653                                             GLOBAL_BITMAP_SYSTEM_INODE,
654                                             OCFS2_INVALID_SLOT,
655                                             &goal_bit, &gd_bh);
656         if (ret) {
657                 mlog_errno(ret);
658                 goto out_commit;
659         }
660
661         /*
662          * probe the victim cluster group to find a proper
663          * region to fit wanted movement, it even will perfrom
664          * a best-effort attempt by compromising to a threshold
665          * around the goal.
666          */
667         ocfs2_probe_alloc_group(inode, gd_bh, &goal_bit, len, move_max_hop,
668                                 new_phys_cpos);
669         if (!*new_phys_cpos) {
670                 ret = -ENOSPC;
671                 goto out_commit;
672         }
673
674         ret = __ocfs2_move_extent(handle, context, cpos, len, phys_cpos,
675                                   *new_phys_cpos, ext_flags);
676         if (ret) {
677                 mlog_errno(ret);
678                 goto out_commit;
679         }
680
681         gd = (struct ocfs2_group_desc *)gd_bh->b_data;
682         ret = ocfs2_alloc_dinode_update_counts(gb_inode, handle, gb_bh, len,
683                                                le16_to_cpu(gd->bg_chain));
684         if (ret) {
685                 mlog_errno(ret);
686                 goto out_commit;
687         }
688
689         ret = ocfs2_block_group_set_bits(handle, gb_inode, gd, gd_bh,
690                                          goal_bit, len);
691         if (ret) {
692                 ocfs2_rollback_alloc_dinode_counts(gb_inode, gb_bh, len,
693                                                le16_to_cpu(gd->bg_chain));
694                 mlog_errno(ret);
695         }
696
697         /*
698          * Here we should write the new page out first if we are
699          * in write-back mode.
700          */
701         ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, len);
702         if (ret)
703                 mlog_errno(ret);
704
705 out_commit:
706         ocfs2_commit_trans(osb, handle);
707         brelse(gd_bh);
708
709 out_unlock_tl_inode:
710         inode_unlock(tl_inode);
711
712         ocfs2_inode_unlock(gb_inode, 1);
713 out_unlock_gb_mutex:
714         inode_unlock(gb_inode);
715         brelse(gb_bh);
716         iput(gb_inode);
717
718 out:
719         if (context->meta_ac) {
720                 ocfs2_free_alloc_context(context->meta_ac);
721                 context->meta_ac = NULL;
722         }
723
724         if (ref_tree)
725                 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
726
727         return ret;
728 }
729
730 /*
731  * Helper to calculate the defraging length in one run according to threshold.
732  */
733 static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
734                                          u32 threshold, int *skip)
735 {
736         if ((*alloc_size + *len_defraged) < threshold) {
737                 /*
738                  * proceed defragmentation until we meet the thresh
739                  */
740                 *len_defraged += *alloc_size;
741         } else if (*len_defraged == 0) {
742                 /*
743                  * XXX: skip a large extent.
744                  */
745                 *skip = 1;
746         } else {
747                 /*
748                  * split this extent to coalesce with former pieces as
749                  * to reach the threshold.
750                  *
751                  * we're done here with one cycle of defragmentation
752                  * in a size of 'thresh', resetting 'len_defraged'
753                  * forces a new defragmentation.
754                  */
755                 *alloc_size = threshold - *len_defraged;
756                 *len_defraged = 0;
757         }
758 }
759
760 static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
761                                 struct ocfs2_move_extents_context *context)
762 {
763         int ret = 0, flags, do_defrag, skip = 0;
764         u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
765         u32 len_defraged = 0, defrag_thresh = 0, new_phys_cpos = 0;
766
767         struct inode *inode = context->inode;
768         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
769         struct ocfs2_move_extents *range = context->range;
770         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
771
772         if ((i_size_read(inode) == 0) || (range->me_len == 0))
773                 return 0;
774
775         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
776                 return 0;
777
778         context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
779
780         ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
781         ocfs2_init_dealloc_ctxt(&context->dealloc);
782
783         /*
784          * TO-DO XXX:
785          *
786          * - xattr extents.
787          */
788
789         do_defrag = context->auto_defrag;
790
791         /*
792          * extents moving happens in unit of clusters, for the sake
793          * of simplicity, we may ignore two clusters where 'byte_start'
794          * and 'byte_start + len' were within.
795          */
796         move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
797         len_to_move = (range->me_start + range->me_len) >>
798                                                 osb->s_clustersize_bits;
799         if (len_to_move >= move_start)
800                 len_to_move -= move_start;
801         else
802                 len_to_move = 0;
803
804         if (do_defrag) {
805                 defrag_thresh = range->me_threshold >> osb->s_clustersize_bits;
806                 if (defrag_thresh <= 1)
807                         goto done;
808         } else
809                 new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
810                                                          range->me_goal);
811
812         mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
813              "thresh: %u\n",
814              (unsigned long long)OCFS2_I(inode)->ip_blkno,
815              (unsigned long long)range->me_start,
816              (unsigned long long)range->me_len,
817              move_start, len_to_move, defrag_thresh);
818
819         cpos = move_start;
820         while (len_to_move) {
821                 ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
822                                          &flags);
823                 if (ret) {
824                         mlog_errno(ret);
825                         goto out;
826                 }
827
828                 if (alloc_size > len_to_move)
829                         alloc_size = len_to_move;
830
831                 /*
832                  * XXX: how to deal with a hole:
833                  *
834                  * - skip the hole of course
835                  * - force a new defragmentation
836                  */
837                 if (!phys_cpos) {
838                         if (do_defrag)
839                                 len_defraged = 0;
840
841                         goto next;
842                 }
843
844                 if (do_defrag) {
845                         ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
846                                                      defrag_thresh, &skip);
847                         /*
848                          * skip large extents
849                          */
850                         if (skip) {
851                                 skip = 0;
852                                 goto next;
853                         }
854
855                         mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
856                              "alloc_size: %u, len_defraged: %u\n",
857                              cpos, phys_cpos, alloc_size, len_defraged);
858
859                         ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
860                                                   &alloc_size, flags);
861                 } else {
862                         ret = ocfs2_move_extent(context, cpos, phys_cpos,
863                                                 &new_phys_cpos, alloc_size,
864                                                 flags);
865
866                         new_phys_cpos += alloc_size;
867                 }
868
869                 if (ret < 0) {
870                         mlog_errno(ret);
871                         goto out;
872                 }
873
874                 context->clusters_moved += alloc_size;
875 next:
876                 cpos += alloc_size;
877                 len_to_move -= alloc_size;
878         }
879
880 done:
881         range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
882
883 out:
884         range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
885                                                       context->clusters_moved);
886         range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
887                                                        context->new_phys_cpos);
888
889         ocfs2_schedule_truncate_log_flush(osb, 1);
890         ocfs2_run_deallocs(osb, &context->dealloc);
891
892         return ret;
893 }
894
895 static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
896 {
897         int status;
898         handle_t *handle;
899         struct inode *inode = context->inode;
900         struct ocfs2_dinode *di;
901         struct buffer_head *di_bh = NULL;
902         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
903
904         if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
905                 return -EROFS;
906
907         inode_lock(inode);
908
909         /*
910          * This prevents concurrent writes from other nodes
911          */
912         status = ocfs2_rw_lock(inode, 1);
913         if (status) {
914                 mlog_errno(status);
915                 goto out;
916         }
917
918         status = ocfs2_inode_lock(inode, &di_bh, 1);
919         if (status) {
920                 mlog_errno(status);
921                 goto out_rw_unlock;
922         }
923
924         /*
925          * rememer ip_xattr_sem also needs to be held if necessary
926          */
927         down_write(&OCFS2_I(inode)->ip_alloc_sem);
928
929         status = __ocfs2_move_extents_range(di_bh, context);
930
931         up_write(&OCFS2_I(inode)->ip_alloc_sem);
932         if (status) {
933                 mlog_errno(status);
934                 goto out_inode_unlock;
935         }
936
937         /*
938          * We update ctime for these changes
939          */
940         handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
941         if (IS_ERR(handle)) {
942                 status = PTR_ERR(handle);
943                 mlog_errno(status);
944                 goto out_inode_unlock;
945         }
946
947         status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
948                                          OCFS2_JOURNAL_ACCESS_WRITE);
949         if (status) {
950                 mlog_errno(status);
951                 goto out_commit;
952         }
953
954         di = (struct ocfs2_dinode *)di_bh->b_data;
955         inode->i_ctime = current_time(inode);
956         di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
957         di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
958         ocfs2_update_inode_fsync_trans(handle, inode, 0);
959
960         ocfs2_journal_dirty(handle, di_bh);
961
962 out_commit:
963         ocfs2_commit_trans(osb, handle);
964
965 out_inode_unlock:
966         brelse(di_bh);
967         ocfs2_inode_unlock(inode, 1);
968 out_rw_unlock:
969         ocfs2_rw_unlock(inode, 1);
970 out:
971         inode_unlock(inode);
972
973         return status;
974 }
975
976 int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
977 {
978         int status;
979
980         struct inode *inode = file_inode(filp);
981         struct ocfs2_move_extents range;
982         struct ocfs2_move_extents_context *context;
983
984         if (!argp)
985                 return -EINVAL;
986
987         status = mnt_want_write_file(filp);
988         if (status)
989                 return status;
990
991         if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE)) {
992                 status = -EPERM;
993                 goto out_drop;
994         }
995
996         if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
997                 status = -EPERM;
998                 goto out_drop;
999         }
1000
1001         context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
1002         if (!context) {
1003                 status = -ENOMEM;
1004                 mlog_errno(status);
1005                 goto out_drop;
1006         }
1007
1008         context->inode = inode;
1009         context->file = filp;
1010
1011         if (copy_from_user(&range, argp, sizeof(range))) {
1012                 status = -EFAULT;
1013                 goto out_free;
1014         }
1015
1016         if (range.me_start > i_size_read(inode)) {
1017                 status = -EINVAL;
1018                 goto out_free;
1019         }
1020
1021         if (range.me_start + range.me_len > i_size_read(inode))
1022                         range.me_len = i_size_read(inode) - range.me_start;
1023
1024         context->range = &range;
1025
1026         /*
1027          * ok, the default theshold for the defragmentation
1028          * is 1M, since our maximum clustersize was 1M also.
1029          * any thought?
1030          */
1031         if (!range.me_threshold)
1032                 range.me_threshold = 1024 * 1024;
1033
1034         if (range.me_threshold > i_size_read(inode))
1035                 range.me_threshold = i_size_read(inode);
1036
1037         if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
1038                 context->auto_defrag = 1;
1039
1040                 if (range.me_flags & OCFS2_MOVE_EXT_FL_PART_DEFRAG)
1041                         context->partial = 1;
1042         } else {
1043                 /*
1044                  * first best-effort attempt to validate and adjust the goal
1045                  * (physical address in block), while it can't guarantee later
1046                  * operation can succeed all the time since global_bitmap may
1047                  * change a bit over time.
1048                  */
1049
1050                 status = ocfs2_validate_and_adjust_move_goal(inode, &range);
1051                 if (status)
1052                         goto out_copy;
1053         }
1054
1055         status = ocfs2_move_extents(context);
1056         if (status)
1057                 mlog_errno(status);
1058 out_copy:
1059         /*
1060          * movement/defragmentation may end up being partially completed,
1061          * that's the reason why we need to return userspace the finished
1062          * length and new_offset even if failure happens somewhere.
1063          */
1064         if (copy_to_user(argp, &range, sizeof(range)))
1065                 status = -EFAULT;
1066
1067 out_free:
1068         kfree(context);
1069 out_drop:
1070         mnt_drop_write_file(filp);
1071
1072         return status;
1073 }