Linux-libre 5.4.47-gnu
[librecmc/linux-libre.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_journal_access_di(handle, INODE_CACHE(inode),
111                                       context->et.et_root_bh,
112                                       OCFS2_JOURNAL_ACCESS_WRITE);
113         if (ret) {
114                 mlog_errno(ret);
115                 goto out;
116         }
117
118         ret = ocfs2_split_extent(handle, &context->et, path, index,
119                                  &replace_rec, context->meta_ac,
120                                  &context->dealloc);
121         if (ret) {
122                 mlog_errno(ret);
123                 goto out;
124         }
125
126         ocfs2_journal_dirty(handle, context->et.et_root_bh);
127
128         context->new_phys_cpos = new_p_cpos;
129
130         /*
131          * need I to append truncate log for old clusters?
132          */
133         if (old_blkno) {
134                 if (ext_flags & OCFS2_EXT_REFCOUNTED)
135                         ret = ocfs2_decrease_refcount(inode, handle,
136                                         ocfs2_blocks_to_clusters(osb->sb,
137                                                                  old_blkno),
138                                         len, context->meta_ac,
139                                         &context->dealloc, 1);
140                 else
141                         ret = ocfs2_truncate_log_append(osb, handle,
142                                                         old_blkno, len);
143         }
144
145         ocfs2_update_inode_fsync_trans(handle, inode, 0);
146 out:
147         ocfs2_free_path(path);
148         return ret;
149 }
150
151 /*
152  * lock allocator, and reserve appropriate number of bits for
153  * meta blocks.
154  */
155 static int ocfs2_lock_meta_allocator_move_extents(struct inode *inode,
156                                         struct ocfs2_extent_tree *et,
157                                         u32 clusters_to_move,
158                                         u32 extents_to_split,
159                                         struct ocfs2_alloc_context **meta_ac,
160                                         int extra_blocks,
161                                         int *credits)
162 {
163         int ret, num_free_extents;
164         unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
165         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
166
167         num_free_extents = ocfs2_num_free_extents(et);
168         if (num_free_extents < 0) {
169                 ret = num_free_extents;
170                 mlog_errno(ret);
171                 goto out;
172         }
173
174         if (!num_free_extents ||
175             (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
176                 extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
177
178         ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
179         if (ret) {
180                 mlog_errno(ret);
181                 goto out;
182         }
183
184
185         *credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el);
186
187         mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
188              extra_blocks, clusters_to_move, *credits);
189 out:
190         if (ret) {
191                 if (*meta_ac) {
192                         ocfs2_free_alloc_context(*meta_ac);
193                         *meta_ac = NULL;
194                 }
195         }
196
197         return ret;
198 }
199
200 /*
201  * Using one journal handle to guarantee the data consistency in case
202  * crash happens anywhere.
203  *
204  *  XXX: defrag can end up with finishing partial extent as requested,
205  * due to not enough contiguous clusters can be found in allocator.
206  */
207 static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
208                                u32 cpos, u32 phys_cpos, u32 *len, int ext_flags)
209 {
210         int ret, credits = 0, extra_blocks = 0, partial = context->partial;
211         handle_t *handle;
212         struct inode *inode = context->inode;
213         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
214         struct inode *tl_inode = osb->osb_tl_inode;
215         struct ocfs2_refcount_tree *ref_tree = NULL;
216         u32 new_phys_cpos, new_len;
217         u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
218         int need_free = 0;
219
220         if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
221                 BUG_ON(!ocfs2_is_refcount_inode(inode));
222                 BUG_ON(!context->refcount_loc);
223
224                 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
225                                                &ref_tree, NULL);
226                 if (ret) {
227                         mlog_errno(ret);
228                         return ret;
229                 }
230
231                 ret = ocfs2_prepare_refcount_change_for_del(inode,
232                                                         context->refcount_loc,
233                                                         phys_blkno,
234                                                         *len,
235                                                         &credits,
236                                                         &extra_blocks);
237                 if (ret) {
238                         mlog_errno(ret);
239                         goto out;
240                 }
241         }
242
243         ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
244                                                 *len, 1,
245                                                 &context->meta_ac,
246                                                 extra_blocks, &credits);
247         if (ret) {
248                 mlog_errno(ret);
249                 goto out;
250         }
251
252         /*
253          * should be using allocation reservation strategy there?
254          *
255          * if (context->data_ac)
256          *      context->data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
257          */
258
259         inode_lock(tl_inode);
260
261         if (ocfs2_truncate_log_needs_flush(osb)) {
262                 ret = __ocfs2_flush_truncate_log(osb);
263                 if (ret < 0) {
264                         mlog_errno(ret);
265                         goto out_unlock_mutex;
266                 }
267         }
268
269         /*
270          * Make sure ocfs2_reserve_cluster is called after
271          * __ocfs2_flush_truncate_log, otherwise, dead lock may happen.
272          *
273          * If ocfs2_reserve_cluster is called
274          * before __ocfs2_flush_truncate_log, dead lock on global bitmap
275          * may happen.
276          *
277          */
278         ret = ocfs2_reserve_clusters(osb, *len, &context->data_ac);
279         if (ret) {
280                 mlog_errno(ret);
281                 goto out_unlock_mutex;
282         }
283
284         handle = ocfs2_start_trans(osb, credits);
285         if (IS_ERR(handle)) {
286                 ret = PTR_ERR(handle);
287                 mlog_errno(ret);
288                 goto out_unlock_mutex;
289         }
290
291         ret = __ocfs2_claim_clusters(handle, context->data_ac, 1, *len,
292                                      &new_phys_cpos, &new_len);
293         if (ret) {
294                 mlog_errno(ret);
295                 goto out_commit;
296         }
297
298         /*
299          * allowing partial extent moving is kind of 'pros and cons', it makes
300          * whole defragmentation less likely to fail, on the contrary, the bad
301          * thing is it may make the fs even more fragmented after moving, let
302          * userspace make a good decision here.
303          */
304         if (new_len != *len) {
305                 mlog(0, "len_claimed: %u, len: %u\n", new_len, *len);
306                 if (!partial) {
307                         context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
308                         ret = -ENOSPC;
309                         need_free = 1;
310                         goto out_commit;
311                 }
312         }
313
314         mlog(0, "cpos: %u, phys_cpos: %u, new_phys_cpos: %u\n", cpos,
315              phys_cpos, new_phys_cpos);
316
317         ret = __ocfs2_move_extent(handle, context, cpos, new_len, phys_cpos,
318                                   new_phys_cpos, ext_flags);
319         if (ret)
320                 mlog_errno(ret);
321
322         if (partial && (new_len != *len))
323                 *len = new_len;
324
325         /*
326          * Here we should write the new page out first if we are
327          * in write-back mode.
328          */
329         ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, *len);
330         if (ret)
331                 mlog_errno(ret);
332
333 out_commit:
334         if (need_free && context->data_ac) {
335                 struct ocfs2_alloc_context *data_ac = context->data_ac;
336
337                 if (context->data_ac->ac_which == OCFS2_AC_USE_LOCAL)
338                         ocfs2_free_local_alloc_bits(osb, handle, data_ac,
339                                         new_phys_cpos, new_len);
340                 else
341                         ocfs2_free_clusters(handle,
342                                         data_ac->ac_inode,
343                                         data_ac->ac_bh,
344                                         ocfs2_clusters_to_blocks(osb->sb, new_phys_cpos),
345                                         new_len);
346         }
347
348         ocfs2_commit_trans(osb, handle);
349
350 out_unlock_mutex:
351         inode_unlock(tl_inode);
352
353         if (context->data_ac) {
354                 ocfs2_free_alloc_context(context->data_ac);
355                 context->data_ac = NULL;
356         }
357
358         if (context->meta_ac) {
359                 ocfs2_free_alloc_context(context->meta_ac);
360                 context->meta_ac = NULL;
361         }
362
363 out:
364         if (ref_tree)
365                 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
366
367         return ret;
368 }
369
370 /*
371  * find the victim alloc group, where #blkno fits.
372  */
373 static int ocfs2_find_victim_alloc_group(struct inode *inode,
374                                          u64 vict_blkno,
375                                          int type, int slot,
376                                          int *vict_bit,
377                                          struct buffer_head **ret_bh)
378 {
379         int ret, i, bits_per_unit = 0;
380         u64 blkno;
381         char namebuf[40];
382
383         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
384         struct buffer_head *ac_bh = NULL, *gd_bh = NULL;
385         struct ocfs2_chain_list *cl;
386         struct ocfs2_chain_rec *rec;
387         struct ocfs2_dinode *ac_dinode;
388         struct ocfs2_group_desc *bg;
389
390         ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type, slot);
391         ret = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
392                                          strlen(namebuf), &blkno);
393         if (ret) {
394                 ret = -ENOENT;
395                 goto out;
396         }
397
398         ret = ocfs2_read_blocks_sync(osb, blkno, 1, &ac_bh);
399         if (ret) {
400                 mlog_errno(ret);
401                 goto out;
402         }
403
404         ac_dinode = (struct ocfs2_dinode *)ac_bh->b_data;
405         cl = &(ac_dinode->id2.i_chain);
406         rec = &(cl->cl_recs[0]);
407
408         if (type == GLOBAL_BITMAP_SYSTEM_INODE)
409                 bits_per_unit = osb->s_clustersize_bits -
410                                         inode->i_sb->s_blocksize_bits;
411         /*
412          * 'vict_blkno' was out of the valid range.
413          */
414         if ((vict_blkno < le64_to_cpu(rec->c_blkno)) ||
415             (vict_blkno >= ((u64)le32_to_cpu(ac_dinode->id1.bitmap1.i_total) <<
416                                 bits_per_unit))) {
417                 ret = -EINVAL;
418                 goto out;
419         }
420
421         for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
422
423                 rec = &(cl->cl_recs[i]);
424                 if (!rec)
425                         continue;
426
427                 bg = NULL;
428
429                 do {
430                         if (!bg)
431                                 blkno = le64_to_cpu(rec->c_blkno);
432                         else
433                                 blkno = le64_to_cpu(bg->bg_next_group);
434
435                         if (gd_bh) {
436                                 brelse(gd_bh);
437                                 gd_bh = NULL;
438                         }
439
440                         ret = ocfs2_read_blocks_sync(osb, blkno, 1, &gd_bh);
441                         if (ret) {
442                                 mlog_errno(ret);
443                                 goto out;
444                         }
445
446                         bg = (struct ocfs2_group_desc *)gd_bh->b_data;
447
448                         if (vict_blkno < (le64_to_cpu(bg->bg_blkno) +
449                                                 le16_to_cpu(bg->bg_bits))) {
450
451                                 *ret_bh = gd_bh;
452                                 *vict_bit = (vict_blkno - blkno) >>
453                                                         bits_per_unit;
454                                 mlog(0, "find the victim group: #%llu, "
455                                      "total_bits: %u, vict_bit: %u\n",
456                                      blkno, le16_to_cpu(bg->bg_bits),
457                                      *vict_bit);
458                                 goto out;
459                         }
460
461                 } while (le64_to_cpu(bg->bg_next_group));
462         }
463
464         ret = -EINVAL;
465 out:
466         brelse(ac_bh);
467
468         /*
469          * caller has to release the gd_bh properly.
470          */
471         return ret;
472 }
473
474 /*
475  * XXX: helper to validate and adjust moving goal.
476  */
477 static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
478                                                struct ocfs2_move_extents *range)
479 {
480         int ret, goal_bit = 0;
481
482         struct buffer_head *gd_bh = NULL;
483         struct ocfs2_group_desc *bg;
484         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
485         int c_to_b = 1 << (osb->s_clustersize_bits -
486                                         inode->i_sb->s_blocksize_bits);
487
488         /*
489          * make goal become cluster aligned.
490          */
491         range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
492                                                       range->me_goal);
493         /*
494          * validate goal sits within global_bitmap, and return the victim
495          * group desc
496          */
497         ret = ocfs2_find_victim_alloc_group(inode, range->me_goal,
498                                             GLOBAL_BITMAP_SYSTEM_INODE,
499                                             OCFS2_INVALID_SLOT,
500                                             &goal_bit, &gd_bh);
501         if (ret)
502                 goto out;
503
504         bg = (struct ocfs2_group_desc *)gd_bh->b_data;
505
506         /*
507          * moving goal is not allowd to start with a group desc blok(#0 blk)
508          * let's compromise to the latter cluster.
509          */
510         if (range->me_goal == le64_to_cpu(bg->bg_blkno))
511                 range->me_goal += c_to_b;
512
513         /*
514          * movement is not gonna cross two groups.
515          */
516         if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <
517                                                                 range->me_len) {
518                 ret = -EINVAL;
519                 goto out;
520         }
521         /*
522          * more exact validations/adjustments will be performed later during
523          * moving operation for each extent range.
524          */
525         mlog(0, "extents get ready to be moved to #%llu block\n",
526              range->me_goal);
527
528 out:
529         brelse(gd_bh);
530
531         return ret;
532 }
533
534 static void ocfs2_probe_alloc_group(struct inode *inode, struct buffer_head *bh,
535                                     int *goal_bit, u32 move_len, u32 max_hop,
536                                     u32 *phys_cpos)
537 {
538         int i, used, last_free_bits = 0, base_bit = *goal_bit;
539         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
540         u32 base_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
541                                                  le64_to_cpu(gd->bg_blkno));
542
543         for (i = base_bit; i < le16_to_cpu(gd->bg_bits); i++) {
544
545                 used = ocfs2_test_bit(i, (unsigned long *)gd->bg_bitmap);
546                 if (used) {
547                         /*
548                          * we even tried searching the free chunk by jumping
549                          * a 'max_hop' distance, but still failed.
550                          */
551                         if ((i - base_bit) > max_hop) {
552                                 *phys_cpos = 0;
553                                 break;
554                         }
555
556                         if (last_free_bits)
557                                 last_free_bits = 0;
558
559                         continue;
560                 } else
561                         last_free_bits++;
562
563                 if (last_free_bits == move_len) {
564                         *goal_bit = i;
565                         *phys_cpos = base_cpos + i;
566                         break;
567                 }
568         }
569
570         mlog(0, "found phys_cpos: %u to fit the wanted moving.\n", *phys_cpos);
571 }
572
573 static int ocfs2_move_extent(struct ocfs2_move_extents_context *context,
574                              u32 cpos, u32 phys_cpos, u32 *new_phys_cpos,
575                              u32 len, int ext_flags)
576 {
577         int ret, credits = 0, extra_blocks = 0, goal_bit = 0;
578         handle_t *handle;
579         struct inode *inode = context->inode;
580         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
581         struct inode *tl_inode = osb->osb_tl_inode;
582         struct inode *gb_inode = NULL;
583         struct buffer_head *gb_bh = NULL;
584         struct buffer_head *gd_bh = NULL;
585         struct ocfs2_group_desc *gd;
586         struct ocfs2_refcount_tree *ref_tree = NULL;
587         u32 move_max_hop = ocfs2_blocks_to_clusters(inode->i_sb,
588                                                     context->range->me_threshold);
589         u64 phys_blkno, new_phys_blkno;
590
591         phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
592
593         if ((ext_flags & OCFS2_EXT_REFCOUNTED) && len) {
594                 BUG_ON(!ocfs2_is_refcount_inode(inode));
595                 BUG_ON(!context->refcount_loc);
596
597                 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
598                                                &ref_tree, NULL);
599                 if (ret) {
600                         mlog_errno(ret);
601                         return ret;
602                 }
603
604                 ret = ocfs2_prepare_refcount_change_for_del(inode,
605                                                         context->refcount_loc,
606                                                         phys_blkno,
607                                                         len,
608                                                         &credits,
609                                                         &extra_blocks);
610                 if (ret) {
611                         mlog_errno(ret);
612                         goto out;
613                 }
614         }
615
616         ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
617                                                 len, 1,
618                                                 &context->meta_ac,
619                                                 extra_blocks, &credits);
620         if (ret) {
621                 mlog_errno(ret);
622                 goto out;
623         }
624
625         /*
626          * need to count 2 extra credits for global_bitmap inode and
627          * group descriptor.
628          */
629         credits += OCFS2_INODE_UPDATE_CREDITS + 1;
630
631         /*
632          * ocfs2_move_extent() didn't reserve any clusters in lock_allocators()
633          * logic, while we still need to lock the global_bitmap.
634          */
635         gb_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
636                                                OCFS2_INVALID_SLOT);
637         if (!gb_inode) {
638                 mlog(ML_ERROR, "unable to get global_bitmap inode\n");
639                 ret = -EIO;
640                 goto out;
641         }
642
643         inode_lock(gb_inode);
644
645         ret = ocfs2_inode_lock(gb_inode, &gb_bh, 1);
646         if (ret) {
647                 mlog_errno(ret);
648                 goto out_unlock_gb_mutex;
649         }
650
651         inode_lock(tl_inode);
652
653         handle = ocfs2_start_trans(osb, credits);
654         if (IS_ERR(handle)) {
655                 ret = PTR_ERR(handle);
656                 mlog_errno(ret);
657                 goto out_unlock_tl_inode;
658         }
659
660         new_phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *new_phys_cpos);
661         ret = ocfs2_find_victim_alloc_group(inode, new_phys_blkno,
662                                             GLOBAL_BITMAP_SYSTEM_INODE,
663                                             OCFS2_INVALID_SLOT,
664                                             &goal_bit, &gd_bh);
665         if (ret) {
666                 mlog_errno(ret);
667                 goto out_commit;
668         }
669
670         /*
671          * probe the victim cluster group to find a proper
672          * region to fit wanted movement, it even will perfrom
673          * a best-effort attempt by compromising to a threshold
674          * around the goal.
675          */
676         ocfs2_probe_alloc_group(inode, gd_bh, &goal_bit, len, move_max_hop,
677                                 new_phys_cpos);
678         if (!*new_phys_cpos) {
679                 ret = -ENOSPC;
680                 goto out_commit;
681         }
682
683         ret = __ocfs2_move_extent(handle, context, cpos, len, phys_cpos,
684                                   *new_phys_cpos, ext_flags);
685         if (ret) {
686                 mlog_errno(ret);
687                 goto out_commit;
688         }
689
690         gd = (struct ocfs2_group_desc *)gd_bh->b_data;
691         ret = ocfs2_alloc_dinode_update_counts(gb_inode, handle, gb_bh, len,
692                                                le16_to_cpu(gd->bg_chain));
693         if (ret) {
694                 mlog_errno(ret);
695                 goto out_commit;
696         }
697
698         ret = ocfs2_block_group_set_bits(handle, gb_inode, gd, gd_bh,
699                                          goal_bit, len);
700         if (ret) {
701                 ocfs2_rollback_alloc_dinode_counts(gb_inode, gb_bh, len,
702                                                le16_to_cpu(gd->bg_chain));
703                 mlog_errno(ret);
704         }
705
706         /*
707          * Here we should write the new page out first if we are
708          * in write-back mode.
709          */
710         ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, len);
711         if (ret)
712                 mlog_errno(ret);
713
714 out_commit:
715         ocfs2_commit_trans(osb, handle);
716         brelse(gd_bh);
717
718 out_unlock_tl_inode:
719         inode_unlock(tl_inode);
720
721         ocfs2_inode_unlock(gb_inode, 1);
722 out_unlock_gb_mutex:
723         inode_unlock(gb_inode);
724         brelse(gb_bh);
725         iput(gb_inode);
726
727 out:
728         if (context->meta_ac) {
729                 ocfs2_free_alloc_context(context->meta_ac);
730                 context->meta_ac = NULL;
731         }
732
733         if (ref_tree)
734                 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
735
736         return ret;
737 }
738
739 /*
740  * Helper to calculate the defraging length in one run according to threshold.
741  */
742 static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
743                                          u32 threshold, int *skip)
744 {
745         if ((*alloc_size + *len_defraged) < threshold) {
746                 /*
747                  * proceed defragmentation until we meet the thresh
748                  */
749                 *len_defraged += *alloc_size;
750         } else if (*len_defraged == 0) {
751                 /*
752                  * XXX: skip a large extent.
753                  */
754                 *skip = 1;
755         } else {
756                 /*
757                  * split this extent to coalesce with former pieces as
758                  * to reach the threshold.
759                  *
760                  * we're done here with one cycle of defragmentation
761                  * in a size of 'thresh', resetting 'len_defraged'
762                  * forces a new defragmentation.
763                  */
764                 *alloc_size = threshold - *len_defraged;
765                 *len_defraged = 0;
766         }
767 }
768
769 static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
770                                 struct ocfs2_move_extents_context *context)
771 {
772         int ret = 0, flags, do_defrag, skip = 0;
773         u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
774         u32 len_defraged = 0, defrag_thresh = 0, new_phys_cpos = 0;
775
776         struct inode *inode = context->inode;
777         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
778         struct ocfs2_move_extents *range = context->range;
779         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
780
781         if ((i_size_read(inode) == 0) || (range->me_len == 0))
782                 return 0;
783
784         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
785                 return 0;
786
787         context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
788
789         ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
790         ocfs2_init_dealloc_ctxt(&context->dealloc);
791
792         /*
793          * TO-DO XXX:
794          *
795          * - xattr extents.
796          */
797
798         do_defrag = context->auto_defrag;
799
800         /*
801          * extents moving happens in unit of clusters, for the sake
802          * of simplicity, we may ignore two clusters where 'byte_start'
803          * and 'byte_start + len' were within.
804          */
805         move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
806         len_to_move = (range->me_start + range->me_len) >>
807                                                 osb->s_clustersize_bits;
808         if (len_to_move >= move_start)
809                 len_to_move -= move_start;
810         else
811                 len_to_move = 0;
812
813         if (do_defrag) {
814                 defrag_thresh = range->me_threshold >> osb->s_clustersize_bits;
815                 if (defrag_thresh <= 1)
816                         goto done;
817         } else
818                 new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
819                                                          range->me_goal);
820
821         mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
822              "thresh: %u\n",
823              (unsigned long long)OCFS2_I(inode)->ip_blkno,
824              (unsigned long long)range->me_start,
825              (unsigned long long)range->me_len,
826              move_start, len_to_move, defrag_thresh);
827
828         cpos = move_start;
829         while (len_to_move) {
830                 ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
831                                          &flags);
832                 if (ret) {
833                         mlog_errno(ret);
834                         goto out;
835                 }
836
837                 if (alloc_size > len_to_move)
838                         alloc_size = len_to_move;
839
840                 /*
841                  * XXX: how to deal with a hole:
842                  *
843                  * - skip the hole of course
844                  * - force a new defragmentation
845                  */
846                 if (!phys_cpos) {
847                         if (do_defrag)
848                                 len_defraged = 0;
849
850                         goto next;
851                 }
852
853                 if (do_defrag) {
854                         ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
855                                                      defrag_thresh, &skip);
856                         /*
857                          * skip large extents
858                          */
859                         if (skip) {
860                                 skip = 0;
861                                 goto next;
862                         }
863
864                         mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
865                              "alloc_size: %u, len_defraged: %u\n",
866                              cpos, phys_cpos, alloc_size, len_defraged);
867
868                         ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
869                                                   &alloc_size, flags);
870                 } else {
871                         ret = ocfs2_move_extent(context, cpos, phys_cpos,
872                                                 &new_phys_cpos, alloc_size,
873                                                 flags);
874
875                         new_phys_cpos += alloc_size;
876                 }
877
878                 if (ret < 0) {
879                         mlog_errno(ret);
880                         goto out;
881                 }
882
883                 context->clusters_moved += alloc_size;
884 next:
885                 cpos += alloc_size;
886                 len_to_move -= alloc_size;
887         }
888
889 done:
890         range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
891
892 out:
893         range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
894                                                       context->clusters_moved);
895         range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
896                                                        context->new_phys_cpos);
897
898         ocfs2_schedule_truncate_log_flush(osb, 1);
899         ocfs2_run_deallocs(osb, &context->dealloc);
900
901         return ret;
902 }
903
904 static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
905 {
906         int status;
907         handle_t *handle;
908         struct inode *inode = context->inode;
909         struct ocfs2_dinode *di;
910         struct buffer_head *di_bh = NULL;
911         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
912
913         if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
914                 return -EROFS;
915
916         inode_lock(inode);
917
918         /*
919          * This prevents concurrent writes from other nodes
920          */
921         status = ocfs2_rw_lock(inode, 1);
922         if (status) {
923                 mlog_errno(status);
924                 goto out;
925         }
926
927         status = ocfs2_inode_lock(inode, &di_bh, 1);
928         if (status) {
929                 mlog_errno(status);
930                 goto out_rw_unlock;
931         }
932
933         /*
934          * rememer ip_xattr_sem also needs to be held if necessary
935          */
936         down_write(&OCFS2_I(inode)->ip_alloc_sem);
937
938         status = __ocfs2_move_extents_range(di_bh, context);
939
940         up_write(&OCFS2_I(inode)->ip_alloc_sem);
941         if (status) {
942                 mlog_errno(status);
943                 goto out_inode_unlock;
944         }
945
946         /*
947          * We update ctime for these changes
948          */
949         handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
950         if (IS_ERR(handle)) {
951                 status = PTR_ERR(handle);
952                 mlog_errno(status);
953                 goto out_inode_unlock;
954         }
955
956         status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
957                                          OCFS2_JOURNAL_ACCESS_WRITE);
958         if (status) {
959                 mlog_errno(status);
960                 goto out_commit;
961         }
962
963         di = (struct ocfs2_dinode *)di_bh->b_data;
964         inode->i_ctime = current_time(inode);
965         di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
966         di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
967         ocfs2_update_inode_fsync_trans(handle, inode, 0);
968
969         ocfs2_journal_dirty(handle, di_bh);
970
971 out_commit:
972         ocfs2_commit_trans(osb, handle);
973
974 out_inode_unlock:
975         brelse(di_bh);
976         ocfs2_inode_unlock(inode, 1);
977 out_rw_unlock:
978         ocfs2_rw_unlock(inode, 1);
979 out:
980         inode_unlock(inode);
981
982         return status;
983 }
984
985 int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
986 {
987         int status;
988
989         struct inode *inode = file_inode(filp);
990         struct ocfs2_move_extents range;
991         struct ocfs2_move_extents_context *context;
992
993         if (!argp)
994                 return -EINVAL;
995
996         status = mnt_want_write_file(filp);
997         if (status)
998                 return status;
999
1000         if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE)) {
1001                 status = -EPERM;
1002                 goto out_drop;
1003         }
1004
1005         if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
1006                 status = -EPERM;
1007                 goto out_drop;
1008         }
1009
1010         context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
1011         if (!context) {
1012                 status = -ENOMEM;
1013                 mlog_errno(status);
1014                 goto out_drop;
1015         }
1016
1017         context->inode = inode;
1018         context->file = filp;
1019
1020         if (copy_from_user(&range, argp, sizeof(range))) {
1021                 status = -EFAULT;
1022                 goto out_free;
1023         }
1024
1025         if (range.me_start > i_size_read(inode)) {
1026                 status = -EINVAL;
1027                 goto out_free;
1028         }
1029
1030         if (range.me_start + range.me_len > i_size_read(inode))
1031                         range.me_len = i_size_read(inode) - range.me_start;
1032
1033         context->range = &range;
1034
1035         if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
1036                 context->auto_defrag = 1;
1037                 /*
1038                  * ok, the default theshold for the defragmentation
1039                  * is 1M, since our maximum clustersize was 1M also.
1040                  * any thought?
1041                  */
1042                 if (!range.me_threshold)
1043                         range.me_threshold = 1024 * 1024;
1044
1045                 if (range.me_threshold > i_size_read(inode))
1046                         range.me_threshold = i_size_read(inode);
1047
1048                 if (range.me_flags & OCFS2_MOVE_EXT_FL_PART_DEFRAG)
1049                         context->partial = 1;
1050         } else {
1051                 /*
1052                  * first best-effort attempt to validate and adjust the goal
1053                  * (physical address in block), while it can't guarantee later
1054                  * operation can succeed all the time since global_bitmap may
1055                  * change a bit over time.
1056                  */
1057
1058                 status = ocfs2_validate_and_adjust_move_goal(inode, &range);
1059                 if (status)
1060                         goto out_copy;
1061         }
1062
1063         status = ocfs2_move_extents(context);
1064         if (status)
1065                 mlog_errno(status);
1066 out_copy:
1067         /*
1068          * movement/defragmentation may end up being partially completed,
1069          * that's the reason why we need to return userspace the finished
1070          * length and new_offset even if failure happens somewhere.
1071          */
1072         if (copy_to_user(argp, &range, sizeof(range)))
1073                 status = -EFAULT;
1074
1075 out_free:
1076         kfree(context);
1077 out_drop:
1078         mnt_drop_write_file(filp);
1079
1080         return status;
1081 }