forked from Sricharanti/sricharan
-
Notifications
You must be signed in to change notification settings - Fork 0
/
gc.c
1378 lines (1181 loc) · 42.9 KB
/
gc.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright © 2001-2007 Red Hat, Inc.
* Copyright © 2004-2010 David Woodhouse <[email protected]>
*
* Created by David Woodhouse <[email protected]>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/mtd/mtd.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/crc32.h>
#include <linux/compiler.h>
#include <linux/stat.h>
#include "nodelist.h"
#include "compr.h"
static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
struct jffs2_inode_cache *ic,
struct jffs2_raw_node_ref *raw);
static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dnode *fd);
static int jffs2_garbage_collect_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dirent *fd);
static int jffs2_garbage_collect_deletion_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dirent *fd);
static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dnode *fn,
uint32_t start, uint32_t end);
static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dnode *fn,
uint32_t start, uint32_t end);
static int jffs2_garbage_collect_live(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_raw_node_ref *raw, struct jffs2_inode_info *f);
/* Called with erase_completion_lock held */
static struct jffs2_eraseblock *jffs2_find_gc_block(struct jffs2_sb_info *c)
{
struct jffs2_eraseblock *ret;
struct list_head *nextlist = NULL;
int n = jiffies % 128;
/* Pick an eraseblock to garbage collect next. This is where we'll
put the clever wear-levelling algorithms. Eventually. */
/* We possibly want to favour the dirtier blocks more when the
number of free blocks is low. */
again:
if (!list_empty(&c->bad_used_list) && c->nr_free_blocks > c->resv_blocks_gcbad) {
jffs2_dbg(1, "Picking block from bad_used_list to GC next\n");
nextlist = &c->bad_used_list;
} else if (n < 50 && !list_empty(&c->erasable_list)) {
/* Note that most of them will have gone directly to be erased.
So don't favour the erasable_list _too_ much. */
jffs2_dbg(1, "Picking block from erasable_list to GC next\n");
nextlist = &c->erasable_list;
} else if (n < 110 && !list_empty(&c->very_dirty_list)) {
/* Most of the time, pick one off the very_dirty list */
jffs2_dbg(1, "Picking block from very_dirty_list to GC next\n");
nextlist = &c->very_dirty_list;
} else if (n < 126 && !list_empty(&c->dirty_list)) {
jffs2_dbg(1, "Picking block from dirty_list to GC next\n");
nextlist = &c->dirty_list;
} else if (!list_empty(&c->clean_list)) {
jffs2_dbg(1, "Picking block from clean_list to GC next\n");
nextlist = &c->clean_list;
} else if (!list_empty(&c->dirty_list)) {
jffs2_dbg(1, "Picking block from dirty_list to GC next (clean_list was empty)\n");
nextlist = &c->dirty_list;
} else if (!list_empty(&c->very_dirty_list)) {
jffs2_dbg(1, "Picking block from very_dirty_list to GC next (clean_list and dirty_list were empty)\n");
nextlist = &c->very_dirty_list;
} else if (!list_empty(&c->erasable_list)) {
jffs2_dbg(1, "Picking block from erasable_list to GC next (clean_list and {very_,}dirty_list were empty)\n");
nextlist = &c->erasable_list;
} else if (!list_empty(&c->erasable_pending_wbuf_list)) {
/* There are blocks are wating for the wbuf sync */
jffs2_dbg(1, "Synching wbuf in order to reuse erasable_pending_wbuf_list blocks\n");
spin_unlock(&c->erase_completion_lock);
jffs2_flush_wbuf_pad(c);
spin_lock(&c->erase_completion_lock);
goto again;
} else {
/* Eep. All were empty */
jffs2_dbg(1, "No clean, dirty _or_ erasable blocks to GC from! Where are they all?\n");
return NULL;
}
ret = list_entry(nextlist->next, struct jffs2_eraseblock, list);
list_del(&ret->list);
c->gcblock = ret;
ret->gc_node = ret->first_node;
if (!ret->gc_node) {
pr_warn("Eep. ret->gc_node for block at 0x%08x is NULL\n",
ret->offset);
BUG();
}
/* Have we accidentally picked a clean block with wasted space ? */
if (ret->wasted_size) {
jffs2_dbg(1, "Converting wasted_size %08x to dirty_size\n",
ret->wasted_size);
ret->dirty_size += ret->wasted_size;
c->wasted_size -= ret->wasted_size;
c->dirty_size += ret->wasted_size;
ret->wasted_size = 0;
}
return ret;
}
/* jffs2_garbage_collect_pass
* Make a single attempt to progress GC. Move one node, and possibly
* start erasing one eraseblock.
*/
int jffs2_garbage_collect_pass(struct jffs2_sb_info *c)
{
struct jffs2_inode_info *f;
struct jffs2_inode_cache *ic;
struct jffs2_eraseblock *jeb;
struct jffs2_raw_node_ref *raw;
uint32_t gcblock_dirty;
int ret = 0, inum, nlink;
int xattr = 0;
if (mutex_lock_interruptible(&c->alloc_sem))
return -EINTR;
for (;;) {
spin_lock(&c->erase_completion_lock);
if (!c->unchecked_size)
break;
/* We can't start doing GC yet. We haven't finished checking
the node CRCs etc. Do it now. */
/* checked_ino is protected by the alloc_sem */
if (c->checked_ino > c->highest_ino && xattr) {
pr_crit("Checked all inodes but still 0x%x bytes of unchecked space?\n",
c->unchecked_size);
jffs2_dbg_dump_block_lists_nolock(c);
spin_unlock(&c->erase_completion_lock);
mutex_unlock(&c->alloc_sem);
return -ENOSPC;
}
spin_unlock(&c->erase_completion_lock);
if (!xattr)
xattr = jffs2_verify_xattr(c);
spin_lock(&c->inocache_lock);
ic = jffs2_get_ino_cache(c, c->checked_ino++);
if (!ic) {
spin_unlock(&c->inocache_lock);
continue;
}
if (!ic->pino_nlink) {
jffs2_dbg(1, "Skipping check of ino #%d with nlink/pino zero\n",
ic->ino);
spin_unlock(&c->inocache_lock);
jffs2_xattr_delete_inode(c, ic);
continue;
}
switch(ic->state) {
case INO_STATE_CHECKEDABSENT:
case INO_STATE_PRESENT:
jffs2_dbg(1, "Skipping ino #%u already checked\n",
ic->ino);
spin_unlock(&c->inocache_lock);
continue;
case INO_STATE_GC:
case INO_STATE_CHECKING:
pr_warn("Inode #%u is in state %d during CRC check phase!\n",
ic->ino, ic->state);
spin_unlock(&c->inocache_lock);
BUG();
case INO_STATE_READING:
/* We need to wait for it to finish, lest we move on
and trigger the BUG() above while we haven't yet
finished checking all its nodes */
jffs2_dbg(1, "Waiting for ino #%u to finish reading\n",
ic->ino);
/* We need to come back again for the _same_ inode. We've
made no progress in this case, but that should be OK */
c->checked_ino--;
mutex_unlock(&c->alloc_sem);
sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
return 0;
default:
BUG();
case INO_STATE_UNCHECKED:
;
}
ic->state = INO_STATE_CHECKING;
spin_unlock(&c->inocache_lock);
jffs2_dbg(1, "%s(): triggering inode scan of ino#%u\n",
__func__, ic->ino);
ret = jffs2_do_crccheck_inode(c, ic);
if (ret)
pr_warn("Returned error for crccheck of ino #%u. Expect badness...\n",
ic->ino);
jffs2_set_inocache_state(c, ic, INO_STATE_CHECKEDABSENT);
mutex_unlock(&c->alloc_sem);
return ret;
}
/* If there are any blocks which need erasing, erase them now */
if (!list_empty(&c->erase_complete_list) ||
!list_empty(&c->erase_pending_list)) {
spin_unlock(&c->erase_completion_lock);
mutex_unlock(&c->alloc_sem);
jffs2_dbg(1, "%s(): erasing pending blocks\n", __func__);
if (jffs2_erase_pending_blocks(c, 1))
return 0;
jffs2_dbg(1, "No progress from erasing block; doing GC anyway\n");
mutex_lock(&c->alloc_sem);
spin_lock(&c->erase_completion_lock);
}
/* First, work out which block we're garbage-collecting */
jeb = c->gcblock;
if (!jeb)
jeb = jffs2_find_gc_block(c);
if (!jeb) {
/* Couldn't find a free block. But maybe we can just erase one and make 'progress'? */
if (c->nr_erasing_blocks) {
spin_unlock(&c->erase_completion_lock);
mutex_unlock(&c->alloc_sem);
return -EAGAIN;
}
jffs2_dbg(1, "Couldn't find erase block to garbage collect!\n");
spin_unlock(&c->erase_completion_lock);
mutex_unlock(&c->alloc_sem);
return -EIO;
}
jffs2_dbg(1, "GC from block %08x, used_size %08x, dirty_size %08x, free_size %08x\n",
jeb->offset, jeb->used_size, jeb->dirty_size, jeb->free_size);
D1(if (c->nextblock)
printk(KERN_DEBUG "Nextblock at %08x, used_size %08x, dirty_size %08x, wasted_size %08x, free_size %08x\n", c->nextblock->offset, c->nextblock->used_size, c->nextblock->dirty_size, c->nextblock->wasted_size, c->nextblock->free_size));
if (!jeb->used_size) {
mutex_unlock(&c->alloc_sem);
goto eraseit;
}
raw = jeb->gc_node;
gcblock_dirty = jeb->dirty_size;
while(ref_obsolete(raw)) {
jffs2_dbg(1, "Node at 0x%08x is obsolete... skipping\n",
ref_offset(raw));
raw = ref_next(raw);
if (unlikely(!raw)) {
pr_warn("eep. End of raw list while still supposedly nodes to GC\n");
pr_warn("erase block at 0x%08x. free_size 0x%08x, dirty_size 0x%08x, used_size 0x%08x\n",
jeb->offset, jeb->free_size,
jeb->dirty_size, jeb->used_size);
jeb->gc_node = raw;
spin_unlock(&c->erase_completion_lock);
mutex_unlock(&c->alloc_sem);
BUG();
}
}
jeb->gc_node = raw;
jffs2_dbg(1, "Going to garbage collect node at 0x%08x\n",
ref_offset(raw));
if (!raw->next_in_ino) {
/* Inode-less node. Clean marker, snapshot or something like that */
spin_unlock(&c->erase_completion_lock);
if (ref_flags(raw) == REF_PRISTINE) {
/* It's an unknown node with JFFS2_FEATURE_RWCOMPAT_COPY */
jffs2_garbage_collect_pristine(c, NULL, raw);
} else {
/* Just mark it obsolete */
jffs2_mark_node_obsolete(c, raw);
}
mutex_unlock(&c->alloc_sem);
goto eraseit_lock;
}
ic = jffs2_raw_ref_to_ic(raw);
#ifdef CONFIG_JFFS2_FS_XATTR
/* When 'ic' refers xattr_datum/xattr_ref, this node is GCed as xattr.
* We can decide whether this node is inode or xattr by ic->class. */
if (ic->class == RAWNODE_CLASS_XATTR_DATUM
|| ic->class == RAWNODE_CLASS_XATTR_REF) {
spin_unlock(&c->erase_completion_lock);
if (ic->class == RAWNODE_CLASS_XATTR_DATUM) {
ret = jffs2_garbage_collect_xattr_datum(c, (struct jffs2_xattr_datum *)ic, raw);
} else {
ret = jffs2_garbage_collect_xattr_ref(c, (struct jffs2_xattr_ref *)ic, raw);
}
goto test_gcnode;
}
#endif
/* We need to hold the inocache. Either the erase_completion_lock or
the inocache_lock are sufficient; we trade down since the inocache_lock
causes less contention. */
spin_lock(&c->inocache_lock);
spin_unlock(&c->erase_completion_lock);
jffs2_dbg(1, "%s(): collecting from block @0x%08x. Node @0x%08x(%d), ino #%u\n",
__func__, jeb->offset, ref_offset(raw), ref_flags(raw),
ic->ino);
/* Three possibilities:
1. Inode is already in-core. We must iget it and do proper
updating to its fragtree, etc.
2. Inode is not in-core, node is REF_PRISTINE. We lock the
inocache to prevent a read_inode(), copy the node intact.
3. Inode is not in-core, node is not pristine. We must iget()
and take the slow path.
*/
switch(ic->state) {
case INO_STATE_CHECKEDABSENT:
/* It's been checked, but it's not currently in-core.
We can just copy any pristine nodes, but have
to prevent anyone else from doing read_inode() while
we're at it, so we set the state accordingly */
if (ref_flags(raw) == REF_PRISTINE)
ic->state = INO_STATE_GC;
else {
jffs2_dbg(1, "Ino #%u is absent but node not REF_PRISTINE. Reading.\n",
ic->ino);
}
break;
case INO_STATE_PRESENT:
/* It's in-core. GC must iget() it. */
break;
case INO_STATE_UNCHECKED:
case INO_STATE_CHECKING:
case INO_STATE_GC:
/* Should never happen. We should have finished checking
by the time we actually start doing any GC, and since
we're holding the alloc_sem, no other garbage collection
can happen.
*/
pr_crit("Inode #%u already in state %d in jffs2_garbage_collect_pass()!\n",
ic->ino, ic->state);
mutex_unlock(&c->alloc_sem);
spin_unlock(&c->inocache_lock);
BUG();
case INO_STATE_READING:
/* Someone's currently trying to read it. We must wait for
them to finish and then go through the full iget() route
to do the GC. However, sometimes read_inode() needs to get
the alloc_sem() (for marking nodes invalid) so we must
drop the alloc_sem before sleeping. */
mutex_unlock(&c->alloc_sem);
jffs2_dbg(1, "%s(): waiting for ino #%u in state %d\n",
__func__, ic->ino, ic->state);
sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
/* And because we dropped the alloc_sem we must start again from the
beginning. Ponder chance of livelock here -- we're returning success
without actually making any progress.
Q: What are the chances that the inode is back in INO_STATE_READING
again by the time we next enter this function? And that this happens
enough times to cause a real delay?
A: Small enough that I don't care :)
*/
return 0;
}
/* OK. Now if the inode is in state INO_STATE_GC, we are going to copy the
node intact, and we don't have to muck about with the fragtree etc.
because we know it's not in-core. If it _was_ in-core, we go through
all the iget() crap anyway */
if (ic->state == INO_STATE_GC) {
spin_unlock(&c->inocache_lock);
ret = jffs2_garbage_collect_pristine(c, ic, raw);
spin_lock(&c->inocache_lock);
ic->state = INO_STATE_CHECKEDABSENT;
wake_up(&c->inocache_wq);
if (ret != -EBADFD) {
spin_unlock(&c->inocache_lock);
goto test_gcnode;
}
/* Fall through if it wanted us to, with inocache_lock held */
}
/* Prevent the fairly unlikely race where the gcblock is
entirely obsoleted by the final close of a file which had
the only valid nodes in the block, followed by erasure,
followed by freeing of the ic because the erased block(s)
held _all_ the nodes of that inode.... never been seen but
it's vaguely possible. */
inum = ic->ino;
nlink = ic->pino_nlink;
spin_unlock(&c->inocache_lock);
f = jffs2_gc_fetch_inode(c, inum, !nlink);
if (IS_ERR(f)) {
ret = PTR_ERR(f);
goto release_sem;
}
if (!f) {
ret = 0;
goto release_sem;
}
ret = jffs2_garbage_collect_live(c, jeb, raw, f);
jffs2_gc_release_inode(c, f);
test_gcnode:
if (jeb->dirty_size == gcblock_dirty && !ref_obsolete(jeb->gc_node)) {
/* Eep. This really should never happen. GC is broken */
pr_err("Error garbage collecting node at %08x!\n",
ref_offset(jeb->gc_node));
ret = -ENOSPC;
}
release_sem:
mutex_unlock(&c->alloc_sem);
eraseit_lock:
/* If we've finished this block, start it erasing */
spin_lock(&c->erase_completion_lock);
eraseit:
if (c->gcblock && !c->gcblock->used_size) {
jffs2_dbg(1, "Block at 0x%08x completely obsoleted by GC. Moving to erase_pending_list\n",
c->gcblock->offset);
/* We're GC'ing an empty block? */
list_add_tail(&c->gcblock->list, &c->erase_pending_list);
c->gcblock = NULL;
c->nr_erasing_blocks++;
jffs2_garbage_collect_trigger(c);
}
spin_unlock(&c->erase_completion_lock);
return ret;
}
static int jffs2_garbage_collect_live(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_raw_node_ref *raw, struct jffs2_inode_info *f)
{
struct jffs2_node_frag *frag;
struct jffs2_full_dnode *fn = NULL;
struct jffs2_full_dirent *fd;
uint32_t start = 0, end = 0, nrfrags = 0;
int ret = 0;
mutex_lock(&f->sem);
/* Now we have the lock for this inode. Check that it's still the one at the head
of the list. */
spin_lock(&c->erase_completion_lock);
if (c->gcblock != jeb) {
spin_unlock(&c->erase_completion_lock);
jffs2_dbg(1, "GC block is no longer gcblock. Restart\n");
goto upnout;
}
if (ref_obsolete(raw)) {
spin_unlock(&c->erase_completion_lock);
jffs2_dbg(1, "node to be GC'd was obsoleted in the meantime.\n");
/* They'll call again */
goto upnout;
}
spin_unlock(&c->erase_completion_lock);
/* OK. Looks safe. And nobody can get us now because we have the semaphore. Move the block */
if (f->metadata && f->metadata->raw == raw) {
fn = f->metadata;
ret = jffs2_garbage_collect_metadata(c, jeb, f, fn);
goto upnout;
}
/* FIXME. Read node and do lookup? */
for (frag = frag_first(&f->fragtree); frag; frag = frag_next(frag)) {
if (frag->node && frag->node->raw == raw) {
fn = frag->node;
end = frag->ofs + frag->size;
if (!nrfrags++)
start = frag->ofs;
if (nrfrags == frag->node->frags)
break; /* We've found them all */
}
}
if (fn) {
if (ref_flags(raw) == REF_PRISTINE) {
ret = jffs2_garbage_collect_pristine(c, f->inocache, raw);
if (!ret) {
/* Urgh. Return it sensibly. */
frag->node->raw = f->inocache->nodes;
}
if (ret != -EBADFD)
goto upnout;
}
/* We found a datanode. Do the GC */
if((start >> PAGE_CACHE_SHIFT) < ((end-1) >> PAGE_CACHE_SHIFT)) {
/* It crosses a page boundary. Therefore, it must be a hole. */
ret = jffs2_garbage_collect_hole(c, jeb, f, fn, start, end);
} else {
/* It could still be a hole. But we GC the page this way anyway */
ret = jffs2_garbage_collect_dnode(c, jeb, f, fn, start, end);
}
goto upnout;
}
/* Wasn't a dnode. Try dirent */
for (fd = f->dents; fd; fd=fd->next) {
if (fd->raw == raw)
break;
}
if (fd && fd->ino) {
ret = jffs2_garbage_collect_dirent(c, jeb, f, fd);
} else if (fd) {
ret = jffs2_garbage_collect_deletion_dirent(c, jeb, f, fd);
} else {
pr_warn("Raw node at 0x%08x wasn't in node lists for ino #%u\n",
ref_offset(raw), f->inocache->ino);
if (ref_obsolete(raw)) {
pr_warn("But it's obsolete so we don't mind too much\n");
} else {
jffs2_dbg_dump_node(c, ref_offset(raw));
BUG();
}
}
upnout:
mutex_unlock(&f->sem);
return ret;
}
static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
struct jffs2_inode_cache *ic,
struct jffs2_raw_node_ref *raw)
{
union jffs2_node_union *node;
size_t retlen;
int ret;
uint32_t phys_ofs, alloclen;
uint32_t crc, rawlen;
int retried = 0;
jffs2_dbg(1, "Going to GC REF_PRISTINE node at 0x%08x\n",
ref_offset(raw));
alloclen = rawlen = ref_totlen(c, c->gcblock, raw);
/* Ask for a small amount of space (or the totlen if smaller) because we
don't want to force wastage of the end of a block if splitting would
work. */
if (ic && alloclen > sizeof(struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN)
alloclen = sizeof(struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN;
ret = jffs2_reserve_space_gc(c, alloclen, &alloclen, rawlen);
/* 'rawlen' is not the exact summary size; it is only an upper estimation */
if (ret)
return ret;
if (alloclen < rawlen) {
/* Doesn't fit untouched. We'll go the old route and split it */
return -EBADFD;
}
node = kmalloc(rawlen, GFP_KERNEL);
if (!node)
return -ENOMEM;
ret = jffs2_flash_read(c, ref_offset(raw), rawlen, &retlen, (char *)node);
if (!ret && retlen != rawlen)
ret = -EIO;
if (ret)
goto out_node;
crc = crc32(0, node, sizeof(struct jffs2_unknown_node)-4);
if (je32_to_cpu(node->u.hdr_crc) != crc) {
pr_warn("Header CRC failed on REF_PRISTINE node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
ref_offset(raw), je32_to_cpu(node->u.hdr_crc), crc);
goto bail;
}
switch(je16_to_cpu(node->u.nodetype)) {
case JFFS2_NODETYPE_INODE:
crc = crc32(0, node, sizeof(node->i)-8);
if (je32_to_cpu(node->i.node_crc) != crc) {
pr_warn("Node CRC failed on REF_PRISTINE data node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
ref_offset(raw), je32_to_cpu(node->i.node_crc),
crc);
goto bail;
}
if (je32_to_cpu(node->i.dsize)) {
crc = crc32(0, node->i.data, je32_to_cpu(node->i.csize));
if (je32_to_cpu(node->i.data_crc) != crc) {
pr_warn("Data CRC failed on REF_PRISTINE data node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
ref_offset(raw),
je32_to_cpu(node->i.data_crc), crc);
goto bail;
}
}
break;
case JFFS2_NODETYPE_DIRENT:
crc = crc32(0, node, sizeof(node->d)-8);
if (je32_to_cpu(node->d.node_crc) != crc) {
pr_warn("Node CRC failed on REF_PRISTINE dirent node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
ref_offset(raw),
je32_to_cpu(node->d.node_crc), crc);
goto bail;
}
if (strnlen(node->d.name, node->d.nsize) != node->d.nsize) {
pr_warn("Name in dirent node at 0x%08x contains zeroes\n",
ref_offset(raw));
goto bail;
}
if (node->d.nsize) {
crc = crc32(0, node->d.name, node->d.nsize);
if (je32_to_cpu(node->d.name_crc) != crc) {
pr_warn("Name CRC failed on REF_PRISTINE dirent node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
ref_offset(raw),
je32_to_cpu(node->d.name_crc), crc);
goto bail;
}
}
break;
default:
/* If it's inode-less, we don't _know_ what it is. Just copy it intact */
if (ic) {
pr_warn("Unknown node type for REF_PRISTINE node at 0x%08x: 0x%04x\n",
ref_offset(raw), je16_to_cpu(node->u.nodetype));
goto bail;
}
}
/* OK, all the CRCs are good; this node can just be copied as-is. */
retry:
phys_ofs = write_ofs(c);
ret = jffs2_flash_write(c, phys_ofs, rawlen, &retlen, (char *)node);
if (ret || (retlen != rawlen)) {
pr_notice("Write of %d bytes at 0x%08x failed. returned %d, retlen %zd\n",
rawlen, phys_ofs, ret, retlen);
if (retlen) {
jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, rawlen, NULL);
} else {
pr_notice("Not marking the space at 0x%08x as dirty because the flash driver returned retlen zero\n",
phys_ofs);
}
if (!retried) {
/* Try to reallocate space and retry */
uint32_t dummy;
struct jffs2_eraseblock *jeb = &c->blocks[phys_ofs / c->sector_size];
retried = 1;
jffs2_dbg(1, "Retrying failed write of REF_PRISTINE node.\n");
jffs2_dbg_acct_sanity_check(c,jeb);
jffs2_dbg_acct_paranoia_check(c, jeb);
ret = jffs2_reserve_space_gc(c, rawlen, &dummy, rawlen);
/* this is not the exact summary size of it,
it is only an upper estimation */
if (!ret) {
jffs2_dbg(1, "Allocated space at 0x%08x to retry failed write.\n",
phys_ofs);
jffs2_dbg_acct_sanity_check(c,jeb);
jffs2_dbg_acct_paranoia_check(c, jeb);
goto retry;
}
jffs2_dbg(1, "Failed to allocate space to retry failed write: %d!\n",
ret);
}
if (!ret)
ret = -EIO;
goto out_node;
}
jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, rawlen, ic);
jffs2_mark_node_obsolete(c, raw);
jffs2_dbg(1, "WHEEE! GC REF_PRISTINE node at 0x%08x succeeded\n",
ref_offset(raw));
out_node:
kfree(node);
return ret;
bail:
ret = -EBADFD;
goto out_node;
}
static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
{
struct jffs2_full_dnode *new_fn;
struct jffs2_raw_inode ri;
struct jffs2_node_frag *last_frag;
union jffs2_device_node dev;
char *mdata = NULL;
int mdatalen = 0;
uint32_t alloclen, ilen;
int ret;
if (S_ISBLK(JFFS2_F_I_MODE(f)) ||
S_ISCHR(JFFS2_F_I_MODE(f)) ) {
/* For these, we don't actually need to read the old node */
mdatalen = jffs2_encode_dev(&dev, JFFS2_F_I_RDEV(f));
mdata = (char *)&dev;
jffs2_dbg(1, "%s(): Writing %d bytes of kdev_t\n",
__func__, mdatalen);
} else if (S_ISLNK(JFFS2_F_I_MODE(f))) {
mdatalen = fn->size;
mdata = kmalloc(fn->size, GFP_KERNEL);
if (!mdata) {
pr_warn("kmalloc of mdata failed in jffs2_garbage_collect_metadata()\n");
return -ENOMEM;
}
ret = jffs2_read_dnode(c, f, fn, mdata, 0, mdatalen);
if (ret) {
pr_warn("read of old metadata failed in jffs2_garbage_collect_metadata(): %d\n",
ret);
kfree(mdata);
return ret;
}
jffs2_dbg(1, "%s(): Writing %d bites of symlink target\n",
__func__, mdatalen);
}
ret = jffs2_reserve_space_gc(c, sizeof(ri) + mdatalen, &alloclen,
JFFS2_SUMMARY_INODE_SIZE);
if (ret) {
pr_warn("jffs2_reserve_space_gc of %zd bytes for garbage_collect_metadata failed: %d\n",
sizeof(ri) + mdatalen, ret);
goto out;
}
last_frag = frag_last(&f->fragtree);
if (last_frag)
/* Fetch the inode length from the fragtree rather then
* from i_size since i_size may have not been updated yet */
ilen = last_frag->ofs + last_frag->size;
else
ilen = JFFS2_F_I_SIZE(f);
memset(&ri, 0, sizeof(ri));
ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
ri.totlen = cpu_to_je32(sizeof(ri) + mdatalen);
ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
ri.ino = cpu_to_je32(f->inocache->ino);
ri.version = cpu_to_je32(++f->highest_version);
ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f));
ri.uid = cpu_to_je16(JFFS2_F_I_UID(f));
ri.gid = cpu_to_je16(JFFS2_F_I_GID(f));
ri.isize = cpu_to_je32(ilen);
ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f));
ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f));
ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f));
ri.offset = cpu_to_je32(0);
ri.csize = cpu_to_je32(mdatalen);
ri.dsize = cpu_to_je32(mdatalen);
ri.compr = JFFS2_COMPR_NONE;
ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
ri.data_crc = cpu_to_je32(crc32(0, mdata, mdatalen));
new_fn = jffs2_write_dnode(c, f, &ri, mdata, mdatalen, ALLOC_GC);
if (IS_ERR(new_fn)) {
pr_warn("Error writing new dnode: %ld\n", PTR_ERR(new_fn));
ret = PTR_ERR(new_fn);
goto out;
}
jffs2_mark_node_obsolete(c, fn->raw);
jffs2_free_full_dnode(fn);
f->metadata = new_fn;
out:
if (S_ISLNK(JFFS2_F_I_MODE(f)))
kfree(mdata);
return ret;
}
static int jffs2_garbage_collect_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dirent *fd)
{
struct jffs2_full_dirent *new_fd;
struct jffs2_raw_dirent rd;
uint32_t alloclen;
int ret;
rd.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
rd.nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
rd.nsize = strlen(fd->name);
rd.totlen = cpu_to_je32(sizeof(rd) + rd.nsize);
rd.hdr_crc = cpu_to_je32(crc32(0, &rd, sizeof(struct jffs2_unknown_node)-4));
rd.pino = cpu_to_je32(f->inocache->ino);
rd.version = cpu_to_je32(++f->highest_version);
rd.ino = cpu_to_je32(fd->ino);
/* If the times on this inode were set by explicit utime() they can be different,
so refrain from splatting them. */
if (JFFS2_F_I_MTIME(f) == JFFS2_F_I_CTIME(f))
rd.mctime = cpu_to_je32(JFFS2_F_I_MTIME(f));
else
rd.mctime = cpu_to_je32(0);
rd.type = fd->type;
rd.node_crc = cpu_to_je32(crc32(0, &rd, sizeof(rd)-8));
rd.name_crc = cpu_to_je32(crc32(0, fd->name, rd.nsize));
ret = jffs2_reserve_space_gc(c, sizeof(rd)+rd.nsize, &alloclen,
JFFS2_SUMMARY_DIRENT_SIZE(rd.nsize));
if (ret) {
pr_warn("jffs2_reserve_space_gc of %zd bytes for garbage_collect_dirent failed: %d\n",
sizeof(rd)+rd.nsize, ret);
return ret;
}
new_fd = jffs2_write_dirent(c, f, &rd, fd->name, rd.nsize, ALLOC_GC);
if (IS_ERR(new_fd)) {
pr_warn("jffs2_write_dirent in garbage_collect_dirent failed: %ld\n",
PTR_ERR(new_fd));
return PTR_ERR(new_fd);
}
jffs2_add_fd_to_list(c, new_fd, &f->dents);
return 0;
}
static int jffs2_garbage_collect_deletion_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dirent *fd)
{
struct jffs2_full_dirent **fdp = &f->dents;
int found = 0;
/* On a medium where we can't actually mark nodes obsolete
pernamently, such as NAND flash, we need to work out
whether this deletion dirent is still needed to actively
delete a 'real' dirent with the same name that's still
somewhere else on the flash. */
if (!jffs2_can_mark_obsolete(c)) {
struct jffs2_raw_dirent *rd;
struct jffs2_raw_node_ref *raw;
int ret;
size_t retlen;
int name_len = strlen(fd->name);
uint32_t name_crc = crc32(0, fd->name, name_len);
uint32_t rawlen = ref_totlen(c, jeb, fd->raw);
rd = kmalloc(rawlen, GFP_KERNEL);
if (!rd)
return -ENOMEM;
/* Prevent the erase code from nicking the obsolete node refs while
we're looking at them. I really don't like this extra lock but
can't see any alternative. Suggestions on a postcard to... */
mutex_lock(&c->erase_free_sem);
for (raw = f->inocache->nodes; raw != (void *)f->inocache; raw = raw->next_in_ino) {
cond_resched();
/* We only care about obsolete ones */
if (!(ref_obsolete(raw)))
continue;
/* Any dirent with the same name is going to have the same length... */
if (ref_totlen(c, NULL, raw) != rawlen)
continue;
/* Doesn't matter if there's one in the same erase block. We're going to
delete it too at the same time. */
if (SECTOR_ADDR(raw->flash_offset) == SECTOR_ADDR(fd->raw->flash_offset))
continue;
jffs2_dbg(1, "Check potential deletion dirent at %08x\n",
ref_offset(raw));
/* This is an obsolete node belonging to the same directory, and it's of the right
length. We need to take a closer look...*/
ret = jffs2_flash_read(c, ref_offset(raw), rawlen, &retlen, (char *)rd);
if (ret) {
pr_warn("%s(): Read error (%d) reading obsolete node at %08x\n",
__func__, ret, ref_offset(raw));
/* If we can't read it, we don't need to continue to obsolete it. Continue */
continue;
}
if (retlen != rawlen) {
pr_warn("%s(): Short read (%zd not %u) reading header from obsolete node at %08x\n",
__func__, retlen, rawlen,
ref_offset(raw));
continue;
}
if (je16_to_cpu(rd->nodetype) != JFFS2_NODETYPE_DIRENT)
continue;
/* If the name CRC doesn't match, skip */
if (je32_to_cpu(rd->name_crc) != name_crc)
continue;
/* If the name length doesn't match, or it's another deletion dirent, skip */
if (rd->nsize != name_len || !je32_to_cpu(rd->ino))
continue;
/* OK, check the actual name now */
if (memcmp(rd->name, fd->name, name_len))
continue;
/* OK. The name really does match. There really is still an older node on
the flash which our deletion dirent obsoletes. So we have to write out
a new deletion dirent to replace it */
mutex_unlock(&c->erase_free_sem);
jffs2_dbg(1, "Deletion dirent at %08x still obsoletes real dirent \"%s\" at %08x for ino #%u\n",
ref_offset(fd->raw), fd->name,
ref_offset(raw), je32_to_cpu(rd->ino));
kfree(rd);
return jffs2_garbage_collect_dirent(c, jeb, f, fd);
}
mutex_unlock(&c->erase_free_sem);
kfree(rd);
}
/* FIXME: If we're deleting a dirent which contains the current mtime and ctime,
we should update the metadata node with those times accordingly */
/* No need for it any more. Just mark it obsolete and remove it from the list */
while (*fdp) {
if ((*fdp) == fd) {
found = 1;
*fdp = fd->next;
break;
}
fdp = &(*fdp)->next;
}
if (!found) {
pr_warn("Deletion dirent \"%s\" not found in list for ino #%u\n",
fd->name, f->inocache->ino);
}
jffs2_mark_node_obsolete(c, fd->raw);
jffs2_free_full_dirent(fd);
return 0;
}
static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
struct jffs2_inode_info *f, struct jffs2_full_dnode *fn,
uint32_t start, uint32_t end)
{
struct jffs2_raw_inode ri;
struct jffs2_node_frag *frag;
struct jffs2_full_dnode *new_fn;
uint32_t alloclen, ilen;