forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 4
/
sufile.c
1281 lines (1122 loc) · 33.5 KB
/
sufile.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
// SPDX-License-Identifier: GPL-2.0+
/*
* NILFS segment usage file.
*
* Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
*
* Written by Koji Sato.
* Revised by Ryusuke Konishi.
*/
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/buffer_head.h>
#include <linux/errno.h>
#include "mdt.h"
#include "sufile.h"
#include <trace/events/nilfs2.h>
/**
* struct nilfs_sufile_info - on-memory private data of sufile
* @mi: on-memory private data of metadata file
* @ncleansegs: number of clean segments
* @allocmin: lower limit of allocatable segment range
* @allocmax: upper limit of allocatable segment range
*/
struct nilfs_sufile_info {
struct nilfs_mdt_info mi;
unsigned long ncleansegs;/* number of clean segments */
__u64 allocmin; /* lower limit of allocatable segment range */
__u64 allocmax; /* upper limit of allocatable segment range */
};
static inline struct nilfs_sufile_info *NILFS_SUI(struct inode *sufile)
{
return (struct nilfs_sufile_info *)NILFS_MDT(sufile);
}
static inline unsigned long
nilfs_sufile_segment_usages_per_block(const struct inode *sufile)
{
return NILFS_MDT(sufile)->mi_entries_per_block;
}
static unsigned long
nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum)
{
__u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
t = div64_ul(t, nilfs_sufile_segment_usages_per_block(sufile));
return (unsigned long)t;
}
static unsigned long
nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum)
{
__u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
return do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
}
static unsigned long
nilfs_sufile_segment_usages_in_block(const struct inode *sufile, __u64 curr,
__u64 max)
{
return min_t(unsigned long,
nilfs_sufile_segment_usages_per_block(sufile) -
nilfs_sufile_get_offset(sufile, curr),
max - curr + 1);
}
static struct nilfs_segment_usage *
nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum,
struct buffer_head *bh, void *kaddr)
{
return kaddr + bh_offset(bh) +
nilfs_sufile_get_offset(sufile, segnum) *
NILFS_MDT(sufile)->mi_entry_size;
}
static int nilfs_sufile_get_header_block(struct inode *sufile,
struct buffer_head **bhp)
{
int err = nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);
if (unlikely(err == -ENOENT)) {
nilfs_error(sufile->i_sb,
"missing header block in segment usage metadata");
err = -EIO;
}
return err;
}
static inline int
nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,
int create, struct buffer_head **bhp)
{
return nilfs_mdt_get_block(sufile,
nilfs_sufile_get_blkoff(sufile, segnum),
create, NULL, bhp);
}
static int nilfs_sufile_delete_segment_usage_block(struct inode *sufile,
__u64 segnum)
{
return nilfs_mdt_delete_block(sufile,
nilfs_sufile_get_blkoff(sufile, segnum));
}
static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,
u64 ncleanadd, u64 ndirtyadd)
{
struct nilfs_sufile_header *header;
void *kaddr;
kaddr = kmap_local_page(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
le64_add_cpu(&header->sh_ncleansegs, ncleanadd);
le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);
kunmap_local(kaddr);
mark_buffer_dirty(header_bh);
}
/**
* nilfs_sufile_get_ncleansegs - return the number of clean segments
* @sufile: inode of segment usage file
*/
unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile)
{
return NILFS_SUI(sufile)->ncleansegs;
}
/**
* nilfs_sufile_updatev - modify multiple segment usages at a time
* @sufile: inode of segment usage file
* @segnumv: array of segment numbers
* @nsegs: size of @segnumv array
* @create: creation flag
* @ndone: place to store number of modified segments on @segnumv
* @dofunc: primitive operation for the update
*
* Description: nilfs_sufile_updatev() repeatedly calls @dofunc
* against the given array of segments. The @dofunc is called with
* buffers of a header block and the sufile block in which the target
* segment usage entry is contained. If @ndone is given, the number
* of successfully modified segments from the head is stored in the
* place @ndone points to.
*
* Return Value: On success, zero is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOENT - Given segment usage is in hole block (may be returned if
* @create is zero)
*
* %-EINVAL - Invalid segment usage number
*/
int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs,
int create, size_t *ndone,
void (*dofunc)(struct inode *, __u64,
struct buffer_head *,
struct buffer_head *))
{
struct buffer_head *header_bh, *bh;
unsigned long blkoff, prev_blkoff;
__u64 *seg;
size_t nerr = 0, n = 0;
int ret = 0;
if (unlikely(nsegs == 0))
goto out;
down_write(&NILFS_MDT(sufile)->mi_sem);
for (seg = segnumv; seg < segnumv + nsegs; seg++) {
if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) {
nilfs_warn(sufile->i_sb,
"%s: invalid segment number: %llu",
__func__, (unsigned long long)*seg);
nerr++;
}
}
if (nerr > 0) {
ret = -EINVAL;
goto out_sem;
}
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
seg = segnumv;
blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
if (ret < 0)
goto out_header;
for (;;) {
dofunc(sufile, *seg, header_bh, bh);
if (++seg >= segnumv + nsegs)
break;
prev_blkoff = blkoff;
blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
if (blkoff == prev_blkoff)
continue;
/* get different block */
brelse(bh);
ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
if (unlikely(ret < 0))
goto out_header;
}
brelse(bh);
out_header:
n = seg - segnumv;
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
out:
if (ndone)
*ndone = n;
return ret;
}
int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create,
void (*dofunc)(struct inode *, __u64,
struct buffer_head *,
struct buffer_head *))
{
struct buffer_head *header_bh, *bh;
int ret;
if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
nilfs_warn(sufile->i_sb, "%s: invalid segment number: %llu",
__func__, (unsigned long long)segnum);
return -EINVAL;
}
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh);
if (!ret) {
dofunc(sufile, segnum, header_bh, bh);
brelse(bh);
}
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_set_alloc_range - limit range of segment to be allocated
* @sufile: inode of segment usage file
* @start: minimum segment number of allocatable region (inclusive)
* @end: maximum segment number of allocatable region (inclusive)
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-ERANGE - invalid segment region
*/
int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end)
{
struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
__u64 nsegs;
int ret = -ERANGE;
down_write(&NILFS_MDT(sufile)->mi_sem);
nsegs = nilfs_sufile_get_nsegments(sufile);
if (start <= end && end < nsegs) {
sui->allocmin = start;
sui->allocmax = end;
ret = 0;
}
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_alloc - allocate a segment
* @sufile: inode of segment usage file
* @segnump: pointer to segment number
*
* Description: nilfs_sufile_alloc() allocates a clean segment.
*
* Return Value: On success, 0 is returned and the segment number of the
* allocated segment is stored in the place pointed by @segnump. On error, one
* of the following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOSPC - No clean segment left.
*/
int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
{
struct buffer_head *header_bh, *su_bh;
struct nilfs_sufile_header *header;
struct nilfs_segment_usage *su;
struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
__u64 segnum, maxsegnum, last_alloc;
void *kaddr;
unsigned long nsegments, nsus, cnt;
int ret, j;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_local_page(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
last_alloc = le64_to_cpu(header->sh_last_alloc);
kunmap_local(kaddr);
nsegments = nilfs_sufile_get_nsegments(sufile);
maxsegnum = sui->allocmax;
segnum = last_alloc + 1;
if (segnum < sui->allocmin || segnum > sui->allocmax)
segnum = sui->allocmin;
for (cnt = 0; cnt < nsegments; cnt += nsus) {
if (segnum > maxsegnum) {
if (cnt < sui->allocmax - sui->allocmin + 1) {
/*
* wrap around in the limited region.
* if allocation started from
* sui->allocmin, this never happens.
*/
segnum = sui->allocmin;
maxsegnum = last_alloc;
} else if (segnum > sui->allocmin &&
sui->allocmax + 1 < nsegments) {
segnum = sui->allocmax + 1;
maxsegnum = nsegments - 1;
} else if (sui->allocmin > 0) {
segnum = 0;
maxsegnum = sui->allocmin - 1;
} else {
break; /* never happens */
}
}
trace_nilfs2_segment_usage_check(sufile, segnum, cnt);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
&su_bh);
if (ret < 0)
goto out_header;
kaddr = kmap_local_page(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
nsus = nilfs_sufile_segment_usages_in_block(
sufile, segnum, maxsegnum);
for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
if (!nilfs_segment_usage_clean(su))
continue;
/* found a clean segment */
nilfs_segment_usage_set_dirty(su);
kunmap_local(kaddr);
kaddr = kmap_local_page(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
le64_add_cpu(&header->sh_ncleansegs, -1);
le64_add_cpu(&header->sh_ndirtysegs, 1);
header->sh_last_alloc = cpu_to_le64(segnum);
kunmap_local(kaddr);
sui->ncleansegs--;
mark_buffer_dirty(header_bh);
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
brelse(su_bh);
*segnump = segnum;
trace_nilfs2_segment_usage_allocated(sufile, segnum);
goto out_header;
}
kunmap_local(kaddr);
brelse(su_bh);
}
/* no segments left */
ret = -ENOSPC;
out_header:
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
kaddr = kmap_local_page(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (unlikely(!nilfs_segment_usage_clean(su))) {
nilfs_warn(sufile->i_sb, "%s: segment %llu must be clean",
__func__, (unsigned long long)segnum);
kunmap_local(kaddr);
return;
}
nilfs_segment_usage_set_dirty(su);
kunmap_local(kaddr);
nilfs_sufile_mod_counter(header_bh, -1, 1);
NILFS_SUI(sufile)->ncleansegs--;
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int clean, dirty;
kaddr = kmap_local_page(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (su->su_flags == cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY)) &&
su->su_nblocks == cpu_to_le32(0)) {
kunmap_local(kaddr);
return;
}
clean = nilfs_segment_usage_clean(su);
dirty = nilfs_segment_usage_dirty(su);
/* make the segment garbage */
su->su_lastmod = cpu_to_le64(0);
su->su_nblocks = cpu_to_le32(0);
su->su_flags = cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY));
kunmap_local(kaddr);
nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);
NILFS_SUI(sufile)->ncleansegs -= clean;
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int sudirty;
kaddr = kmap_local_page(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (nilfs_segment_usage_clean(su)) {
nilfs_warn(sufile->i_sb, "%s: segment %llu is already clean",
__func__, (unsigned long long)segnum);
kunmap_local(kaddr);
return;
}
if (unlikely(nilfs_segment_usage_error(su)))
nilfs_warn(sufile->i_sb, "free segment %llu marked in error",
(unsigned long long)segnum);
sudirty = nilfs_segment_usage_dirty(su);
if (unlikely(!sudirty))
nilfs_warn(sufile->i_sb, "free unallocated segment %llu",
(unsigned long long)segnum);
nilfs_segment_usage_set_clean(su);
kunmap_local(kaddr);
mark_buffer_dirty(su_bh);
nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);
NILFS_SUI(sufile)->ncleansegs++;
nilfs_mdt_mark_dirty(sufile);
trace_nilfs2_segment_usage_freed(sufile, segnum);
}
/**
* nilfs_sufile_mark_dirty - mark the buffer having a segment usage dirty
* @sufile: inode of segment usage file
* @segnum: segment number
*/
int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)
{
struct buffer_head *bh;
void *kaddr;
struct nilfs_segment_usage *su;
int ret;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
if (unlikely(ret)) {
if (ret == -ENOENT) {
nilfs_error(sufile->i_sb,
"segment usage for segment %llu is unreadable due to a hole block",
(unsigned long long)segnum);
ret = -EIO;
}
goto out_sem;
}
kaddr = kmap_local_page(bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);
if (unlikely(nilfs_segment_usage_error(su))) {
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
kunmap_local(kaddr);
brelse(bh);
if (nilfs_segment_is_active(nilfs, segnum)) {
nilfs_error(sufile->i_sb,
"active segment %llu is erroneous",
(unsigned long long)segnum);
} else {
/*
* Segments marked erroneous are never allocated by
* nilfs_sufile_alloc(); only active segments, ie,
* the segments indexed by ns_segnum or ns_nextnum,
* can be erroneous here.
*/
WARN_ON_ONCE(1);
}
ret = -EIO;
} else {
nilfs_segment_usage_set_dirty(su);
kunmap_local(kaddr);
mark_buffer_dirty(bh);
nilfs_mdt_mark_dirty(sufile);
brelse(bh);
}
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_set_segment_usage - set usage of a segment
* @sufile: inode of segment usage file
* @segnum: segment number
* @nblocks: number of live blocks in the segment
* @modtime: modification time (option)
*/
int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
unsigned long nblocks, time64_t modtime)
{
struct buffer_head *bh;
struct nilfs_segment_usage *su;
void *kaddr;
int ret;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_local_page(bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);
if (modtime) {
/*
* Check segusage error and set su_lastmod only when updating
* this entry with a valid timestamp, not for cancellation.
*/
WARN_ON_ONCE(nilfs_segment_usage_error(su));
su->su_lastmod = cpu_to_le64(modtime);
}
su->su_nblocks = cpu_to_le32(nblocks);
kunmap_local(kaddr);
mark_buffer_dirty(bh);
nilfs_mdt_mark_dirty(sufile);
brelse(bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_get_stat - get segment usage statistics
* @sufile: inode of segment usage file
* @sustat: pointer to a structure of segment usage statistics
*
* Description: nilfs_sufile_get_stat() returns information about segment
* usage.
*
* Return Value: On success, 0 is returned, and segment usage information is
* stored in the place pointed by @sustat. On error, one of the following
* negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*/
int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat)
{
struct buffer_head *header_bh;
struct nilfs_sufile_header *header;
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
void *kaddr;
int ret;
down_read(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_local_page(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile);
sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs);
sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs);
sustat->ss_ctime = nilfs->ns_ctime;
sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime;
spin_lock(&nilfs->ns_last_segment_lock);
sustat->ss_prot_seq = nilfs->ns_prot_seq;
spin_unlock(&nilfs->ns_last_segment_lock);
kunmap_local(kaddr);
brelse(header_bh);
out_sem:
up_read(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int suclean;
kaddr = kmap_local_page(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (nilfs_segment_usage_error(su)) {
kunmap_local(kaddr);
return;
}
suclean = nilfs_segment_usage_clean(su);
nilfs_segment_usage_set_error(su);
kunmap_local(kaddr);
if (suclean) {
nilfs_sufile_mod_counter(header_bh, -1, 0);
NILFS_SUI(sufile)->ncleansegs--;
}
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
/**
* nilfs_sufile_truncate_range - truncate range of segment array
* @sufile: inode of segment usage file
* @start: start segment number (inclusive)
* @end: end segment number (inclusive)
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-EINVAL - Invalid number of segments specified
*
* %-EBUSY - Dirty or active segments are present in the range
*/
static int nilfs_sufile_truncate_range(struct inode *sufile,
__u64 start, __u64 end)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *header_bh;
struct buffer_head *su_bh;
struct nilfs_segment_usage *su, *su2;
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
unsigned long segusages_per_block;
unsigned long nsegs, ncleaned;
__u64 segnum;
void *kaddr;
ssize_t n, nc;
int ret;
int j;
nsegs = nilfs_sufile_get_nsegments(sufile);
ret = -EINVAL;
if (start > end || start >= nsegs)
goto out;
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out;
segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
ncleaned = 0;
for (segnum = start; segnum <= end; segnum += n) {
n = min_t(unsigned long,
segusages_per_block -
nilfs_sufile_get_offset(sufile, segnum),
end - segnum + 1);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
&su_bh);
if (ret < 0) {
if (ret != -ENOENT)
goto out_header;
/* hole */
continue;
}
kaddr = kmap_local_page(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
su2 = su;
for (j = 0; j < n; j++, su = (void *)su + susz) {
if ((le32_to_cpu(su->su_flags) &
~BIT(NILFS_SEGMENT_USAGE_ERROR)) ||
nilfs_segment_is_active(nilfs, segnum + j)) {
ret = -EBUSY;
kunmap_local(kaddr);
brelse(su_bh);
goto out_header;
}
}
nc = 0;
for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) {
if (nilfs_segment_usage_error(su)) {
nilfs_segment_usage_set_clean(su);
nc++;
}
}
kunmap_local(kaddr);
if (nc > 0) {
mark_buffer_dirty(su_bh);
ncleaned += nc;
}
brelse(su_bh);
if (n == segusages_per_block) {
/* make hole */
nilfs_sufile_delete_segment_usage_block(sufile, segnum);
}
}
ret = 0;
out_header:
if (ncleaned > 0) {
NILFS_SUI(sufile)->ncleansegs += ncleaned;
nilfs_sufile_mod_counter(header_bh, ncleaned, 0);
nilfs_mdt_mark_dirty(sufile);
}
brelse(header_bh);
out:
return ret;
}
/**
* nilfs_sufile_resize - resize segment array
* @sufile: inode of segment usage file
* @newnsegs: new number of segments
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOSPC - Enough free space is not left for shrinking
*
* %-EBUSY - Dirty or active segments exist in the region to be truncated
*/
int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *header_bh;
struct nilfs_sufile_header *header;
struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
void *kaddr;
unsigned long nsegs, nrsvsegs;
int ret = 0;
down_write(&NILFS_MDT(sufile)->mi_sem);
nsegs = nilfs_sufile_get_nsegments(sufile);
if (nsegs == newnsegs)
goto out;
ret = -ENOSPC;
nrsvsegs = nilfs_nrsvsegs(nilfs, newnsegs);
if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs)
goto out;
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out;
if (newnsegs > nsegs) {
sui->ncleansegs += newnsegs - nsegs;
} else /* newnsegs < nsegs */ {
ret = nilfs_sufile_truncate_range(sufile, newnsegs, nsegs - 1);
if (ret < 0)
goto out_header;
sui->ncleansegs -= nsegs - newnsegs;
/*
* If the sufile is successfully truncated, immediately adjust
* the segment allocation space while locking the semaphore
* "mi_sem" so that nilfs_sufile_alloc() never allocates
* segments in the truncated space.
*/
sui->allocmax = newnsegs - 1;
sui->allocmin = 0;
}
kaddr = kmap_local_page(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs);
kunmap_local(kaddr);
mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(sufile);
nilfs_set_nsegments(nilfs, newnsegs);
out_header:
brelse(header_bh);
out:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_get_suinfo - get segment usage information
* @sufile: inode of segment usage file
* @segnum: segment number to start looking
* @buf: array of suinfo
* @sisz: byte size of suinfo
* @nsi: size of suinfo array
*
* Return: Count of segment usage info items stored in the output buffer on
* success, or the following negative error code on failure.
* * %-EIO - I/O error (including metadata corruption).
* * %-ENOMEM - Insufficient memory available.
*/
ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
unsigned int sisz, size_t nsi)
{
struct buffer_head *su_bh;
struct nilfs_segment_usage *su;
struct nilfs_suinfo *si = buf;
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
void *kaddr;
unsigned long nsegs, segusages_per_block;
ssize_t n;
int ret, i, j;
down_read(&NILFS_MDT(sufile)->mi_sem);
segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
nsegs = min_t(unsigned long,
nilfs_sufile_get_nsegments(sufile) - segnum,
nsi);
for (i = 0; i < nsegs; i += n, segnum += n) {
n = min_t(unsigned long,
segusages_per_block -
nilfs_sufile_get_offset(sufile, segnum),
nsegs - i);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
&su_bh);
if (ret < 0) {
if (ret != -ENOENT)
goto out;
/* hole */
memset(si, 0, sisz * n);
si = (void *)si + sisz * n;
continue;
}
kaddr = kmap_local_page(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
for (j = 0; j < n;
j++, su = (void *)su + susz, si = (void *)si + sisz) {
si->sui_lastmod = le64_to_cpu(su->su_lastmod);
si->sui_nblocks = le32_to_cpu(su->su_nblocks);
si->sui_flags = le32_to_cpu(su->su_flags) &
~BIT(NILFS_SEGMENT_USAGE_ACTIVE);
if (nilfs_segment_is_active(nilfs, segnum + j))
si->sui_flags |=
BIT(NILFS_SEGMENT_USAGE_ACTIVE);
}
kunmap_local(kaddr);
brelse(su_bh);
}
ret = nsegs;
out:
up_read(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_set_suinfo - sets segment usage info
* @sufile: inode of segment usage file
* @buf: array of suinfo_update
* @supsz: byte size of suinfo_update
* @nsup: size of suinfo_update array
*
* Description: Takes an array of nilfs_suinfo_update structs and updates
* segment usage accordingly. Only the fields indicated by the sup_flags
* are updated.
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-EINVAL - Invalid values in input (segment number, flags or nblocks)
*/
ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf,
unsigned int supsz, size_t nsup)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *header_bh, *bh;
struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup;
struct nilfs_segment_usage *su;
void *kaddr;
unsigned long blkoff, prev_blkoff;
int cleansi, cleansu, dirtysi, dirtysu;
long ncleaned = 0, ndirtied = 0;
int ret = 0;
if (unlikely(nsup == 0))
return ret;
for (sup = buf; sup < supend; sup = (void *)sup + supsz) {
if (sup->sup_segnum >= nilfs->ns_nsegments
|| (sup->sup_flags &
(~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS))
|| (nilfs_suinfo_update_nblocks(sup) &&
sup->sup_sui.sui_nblocks >
nilfs->ns_blocks_per_segment))
return -EINVAL;
}
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
sup = buf;
blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
if (ret < 0)
goto out_header;
for (;;) {
kaddr = kmap_local_page(bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, sup->sup_segnum, bh, kaddr);
if (nilfs_suinfo_update_lastmod(sup))
su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod);
if (nilfs_suinfo_update_nblocks(sup))
su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks);
if (nilfs_suinfo_update_flags(sup)) {
/*
* Active flag is a virtual flag projected by running
* nilfs kernel code - drop it not to write it to
* disk.