forked from swarren/WSL2-Linux-Kernel
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathbmap.c
1215 lines (1027 loc) · 28.3 KB
/
bmap.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
/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/lm_interface.h>
#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "inode.h"
#include "meta_io.h"
#include "quota.h"
#include "rgrp.h"
#include "trans.h"
#include "dir.h"
#include "util.h"
#include "ops_address.h"
/* This doesn't need to be that large as max 64 bit pointers in a 4k
* block is 512, so __u16 is fine for that. It saves stack space to
* keep it small.
*/
struct metapath {
__u16 mp_list[GFS2_MAX_META_HEIGHT];
};
typedef int (*block_call_t) (struct gfs2_inode *ip, struct buffer_head *dibh,
struct buffer_head *bh, __be64 *top,
__be64 *bottom, unsigned int height,
void *data);
struct strip_mine {
int sm_first;
unsigned int sm_height;
};
/**
* gfs2_unstuffer_page - unstuff a stuffed inode into a block cached by a page
* @ip: the inode
* @dibh: the dinode buffer
* @block: the block number that was allocated
* @private: any locked page held by the caller process
*
* Returns: errno
*/
static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh,
u64 block, struct page *page)
{
struct inode *inode = &ip->i_inode;
struct buffer_head *bh;
int release = 0;
if (!page || page->index) {
page = grab_cache_page(inode->i_mapping, 0);
if (!page)
return -ENOMEM;
release = 1;
}
if (!PageUptodate(page)) {
void *kaddr = kmap(page);
memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode),
ip->i_di.di_size);
memset(kaddr + ip->i_di.di_size, 0,
PAGE_CACHE_SIZE - ip->i_di.di_size);
kunmap(page);
SetPageUptodate(page);
}
if (!page_has_buffers(page))
create_empty_buffers(page, 1 << inode->i_blkbits,
(1 << BH_Uptodate));
bh = page_buffers(page);
if (!buffer_mapped(bh))
map_bh(bh, inode->i_sb, block);
set_buffer_uptodate(bh);
if (!gfs2_is_jdata(ip))
mark_buffer_dirty(bh);
if (!gfs2_is_writeback(ip))
gfs2_trans_add_bh(ip->i_gl, bh, 0);
if (release) {
unlock_page(page);
page_cache_release(page);
}
return 0;
}
/**
* gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big
* @ip: The GFS2 inode to unstuff
* @unstuffer: the routine that handles unstuffing a non-zero length file
* @private: private data for the unstuffer
*
* This routine unstuffs a dinode and returns it to a "normal" state such
* that the height can be grown in the traditional way.
*
* Returns: errno
*/
int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page)
{
struct buffer_head *bh, *dibh;
struct gfs2_dinode *di;
u64 block = 0;
int isdir = gfs2_is_dir(ip);
int error;
down_write(&ip->i_rw_mutex);
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto out;
if (ip->i_di.di_size) {
/* Get a free block, fill it with the stuffed data,
and write it out to disk */
if (isdir) {
block = gfs2_alloc_meta(ip);
error = gfs2_dir_get_new_buffer(ip, block, &bh);
if (error)
goto out_brelse;
gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_meta_header),
dibh, sizeof(struct gfs2_dinode));
brelse(bh);
} else {
block = gfs2_alloc_data(ip);
error = gfs2_unstuffer_page(ip, dibh, block, page);
if (error)
goto out_brelse;
}
}
/* Set up the pointer to the new block */
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
di = (struct gfs2_dinode *)dibh->b_data;
gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
if (ip->i_di.di_size) {
*(__be64 *)(di + 1) = cpu_to_be64(block);
ip->i_di.di_blocks++;
gfs2_set_inode_blocks(&ip->i_inode);
di->di_blocks = cpu_to_be64(ip->i_di.di_blocks);
}
ip->i_height = 1;
di->di_height = cpu_to_be16(1);
out_brelse:
brelse(dibh);
out:
up_write(&ip->i_rw_mutex);
return error;
}
/**
* build_height - Build a metadata tree of the requested height
* @ip: The GFS2 inode
* @height: The height to build to
*
*
* Returns: errno
*/
static int build_height(struct inode *inode, unsigned height)
{
struct gfs2_inode *ip = GFS2_I(inode);
unsigned new_height = height - ip->i_height;
struct buffer_head *dibh;
struct buffer_head *blocks[GFS2_MAX_META_HEIGHT];
struct gfs2_dinode *di;
int error;
__be64 *bp;
u64 bn;
unsigned n;
if (height <= ip->i_height)
return 0;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
return error;
for(n = 0; n < new_height; n++) {
bn = gfs2_alloc_meta(ip);
blocks[n] = gfs2_meta_new(ip->i_gl, bn);
gfs2_trans_add_bh(ip->i_gl, blocks[n], 1);
}
n = 0;
bn = blocks[0]->b_blocknr;
if (new_height > 1) {
for(; n < new_height-1; n++) {
gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN,
GFS2_FORMAT_IN);
gfs2_buffer_clear_tail(blocks[n],
sizeof(struct gfs2_meta_header));
bp = (__be64 *)(blocks[n]->b_data +
sizeof(struct gfs2_meta_header));
*bp = cpu_to_be64(blocks[n+1]->b_blocknr);
brelse(blocks[n]);
blocks[n] = NULL;
}
}
gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN, GFS2_FORMAT_IN);
gfs2_buffer_copy_tail(blocks[n], sizeof(struct gfs2_meta_header),
dibh, sizeof(struct gfs2_dinode));
brelse(blocks[n]);
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
di = (struct gfs2_dinode *)dibh->b_data;
gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
*(__be64 *)(di + 1) = cpu_to_be64(bn);
ip->i_height += new_height;
ip->i_di.di_blocks += new_height;
gfs2_set_inode_blocks(&ip->i_inode);
di->di_height = cpu_to_be16(ip->i_height);
di->di_blocks = cpu_to_be64(ip->i_di.di_blocks);
brelse(dibh);
return error;
}
/**
* find_metapath - Find path through the metadata tree
* @ip: The inode pointer
* @mp: The metapath to return the result in
* @block: The disk block to look up
*
* This routine returns a struct metapath structure that defines a path
* through the metadata of inode "ip" to get to block "block".
*
* Example:
* Given: "ip" is a height 3 file, "offset" is 101342453, and this is a
* filesystem with a blocksize of 4096.
*
* find_metapath() would return a struct metapath structure set to:
* mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48,
* and mp_list[2] = 165.
*
* That means that in order to get to the block containing the byte at
* offset 101342453, we would load the indirect block pointed to by pointer
* 0 in the dinode. We would then load the indirect block pointed to by
* pointer 48 in that indirect block. We would then load the data block
* pointed to by pointer 165 in that indirect block.
*
* ----------------------------------------
* | Dinode | |
* | | 4|
* | |0 1 2 3 4 5 9|
* | | 6|
* ----------------------------------------
* |
* |
* V
* ----------------------------------------
* | Indirect Block |
* | 5|
* | 4 4 4 4 4 5 5 1|
* |0 5 6 7 8 9 0 1 2|
* ----------------------------------------
* |
* |
* V
* ----------------------------------------
* | Indirect Block |
* | 1 1 1 1 1 5|
* | 6 6 6 6 6 1|
* |0 3 4 5 6 7 2|
* ----------------------------------------
* |
* |
* V
* ----------------------------------------
* | Data block containing offset |
* | 101342453 |
* | |
* | |
* ----------------------------------------
*
*/
static void find_metapath(struct gfs2_inode *ip, u64 block,
struct metapath *mp)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
u64 b = block;
unsigned int i;
for (i = ip->i_height; i--;)
mp->mp_list[i] = do_div(b, sdp->sd_inptrs);
}
/**
* metapointer - Return pointer to start of metadata in a buffer
* @bh: The buffer
* @height: The metadata height (0 = dinode)
* @mp: The metapath
*
* Return a pointer to the block number of the next height of the metadata
* tree given a buffer containing the pointer to the current height of the
* metadata tree.
*/
static inline __be64 *metapointer(struct buffer_head *bh, int *boundary,
unsigned int height, const struct metapath *mp)
{
unsigned int head_size = (height > 0) ?
sizeof(struct gfs2_meta_header) : sizeof(struct gfs2_dinode);
__be64 *ptr;
*boundary = 0;
ptr = ((__be64 *)(bh->b_data + head_size)) + mp->mp_list[height];
if (ptr + 1 == (__be64 *)(bh->b_data + bh->b_size))
*boundary = 1;
return ptr;
}
/**
* lookup_block - Get the next metadata block in metadata tree
* @ip: The GFS2 inode
* @bh: Buffer containing the pointers to metadata blocks
* @height: The height of the tree (0 = dinode)
* @mp: The metapath
* @create: Non-zero if we may create a new meatdata block
* @new: Used to indicate if we did create a new metadata block
* @block: the returned disk block number
*
* Given a metatree, complete to a particular height, checks to see if the next
* height of the tree exists. If not the next height of the tree is created.
* The block number of the next height of the metadata tree is returned.
*
*/
static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh,
unsigned int height, struct metapath *mp, int create,
int *new, u64 *block)
{
int boundary;
__be64 *ptr = metapointer(bh, &boundary, height, mp);
if (*ptr) {
*block = be64_to_cpu(*ptr);
return boundary;
}
*block = 0;
if (!create)
return 0;
if (height == ip->i_height - 1 && !gfs2_is_dir(ip))
*block = gfs2_alloc_data(ip);
else
*block = gfs2_alloc_meta(ip);
gfs2_trans_add_bh(ip->i_gl, bh, 1);
*ptr = cpu_to_be64(*block);
ip->i_di.di_blocks++;
gfs2_set_inode_blocks(&ip->i_inode);
*new = 1;
return 0;
}
static inline void bmap_lock(struct inode *inode, int create)
{
struct gfs2_inode *ip = GFS2_I(inode);
if (create)
down_write(&ip->i_rw_mutex);
else
down_read(&ip->i_rw_mutex);
}
static inline void bmap_unlock(struct inode *inode, int create)
{
struct gfs2_inode *ip = GFS2_I(inode);
if (create)
up_write(&ip->i_rw_mutex);
else
up_read(&ip->i_rw_mutex);
}
/**
* gfs2_block_map - Map a block from an inode to a disk block
* @inode: The inode
* @lblock: The logical block number
* @bh_map: The bh to be mapped
*
* Find the block number on the current device which corresponds to an
* inode's block. If the block had to be created, "new" will be set.
*
* Returns: errno
*/
int gfs2_block_map(struct inode *inode, sector_t lblock,
struct buffer_head *bh_map, int create)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
struct buffer_head *bh;
unsigned int bsize = sdp->sd_sb.sb_bsize;
unsigned int end_of_metadata;
unsigned int x;
int error = 0;
int new = 0;
u64 dblock = 0;
int boundary;
unsigned int maxlen = bh_map->b_size >> inode->i_blkbits;
struct metapath mp;
u64 size;
struct buffer_head *dibh = NULL;
const u64 *arr = sdp->sd_heightsize;
BUG_ON(maxlen == 0);
if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip)))
return 0;
bmap_lock(inode, create);
clear_buffer_mapped(bh_map);
clear_buffer_new(bh_map);
clear_buffer_boundary(bh_map);
if (gfs2_is_dir(ip)) {
bsize = sdp->sd_jbsize;
arr = sdp->sd_jheightsize;
}
size = (lblock + 1) * bsize;
if (size > arr[ip->i_height]) {
u8 height = ip->i_height;
if (!create)
goto out_ok;
while (size > arr[height])
height++;
error = build_height(inode, height);
if (error)
goto out_fail;
}
find_metapath(ip, lblock, &mp);
end_of_metadata = ip->i_height - 1;
error = gfs2_meta_inode_buffer(ip, &bh);
if (error)
goto out_fail;
dibh = bh;
get_bh(dibh);
for (x = 0; x < end_of_metadata; x++) {
lookup_block(ip, bh, x, &mp, create, &new, &dblock);
brelse(bh);
if (!dblock)
goto out_ok;
error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh);
if (error)
goto out_fail;
}
boundary = lookup_block(ip, bh, end_of_metadata, &mp, create, &new, &dblock);
if (dblock) {
map_bh(bh_map, inode->i_sb, dblock);
if (boundary)
set_buffer_boundary(bh_map);
if (new) {
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
set_buffer_new(bh_map);
goto out_brelse;
}
while(--maxlen && !buffer_boundary(bh_map)) {
u64 eblock;
mp.mp_list[end_of_metadata]++;
boundary = lookup_block(ip, bh, end_of_metadata, &mp, 0, &new, &eblock);
if (eblock != ++dblock)
break;
bh_map->b_size += (1 << inode->i_blkbits);
if (boundary)
set_buffer_boundary(bh_map);
}
}
out_brelse:
brelse(bh);
out_ok:
error = 0;
out_fail:
if (dibh)
brelse(dibh);
bmap_unlock(inode, create);
return error;
}
/*
* Deprecated: do not use in new code
*/
int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen)
{
struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 };
int ret;
int create = *new;
BUG_ON(!extlen);
BUG_ON(!dblock);
BUG_ON(!new);
bh.b_size = 1 << (inode->i_blkbits + 5);
ret = gfs2_block_map(inode, lblock, &bh, create);
*extlen = bh.b_size >> inode->i_blkbits;
*dblock = bh.b_blocknr;
if (buffer_new(&bh))
*new = 1;
else
*new = 0;
return ret;
}
/**
* recursive_scan - recursively scan through the end of a file
* @ip: the inode
* @dibh: the dinode buffer
* @mp: the path through the metadata to the point to start
* @height: the height the recursion is at
* @block: the indirect block to look at
* @first: 1 if this is the first block
* @bc: the call to make for each piece of metadata
* @data: data opaque to this function to pass to @bc
*
* When this is first called @height and @block should be zero and
* @first should be 1.
*
* Returns: errno
*/
static int recursive_scan(struct gfs2_inode *ip, struct buffer_head *dibh,
struct metapath *mp, unsigned int height,
u64 block, int first, block_call_t bc,
void *data)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct buffer_head *bh = NULL;
__be64 *top, *bottom;
u64 bn;
int error;
int mh_size = sizeof(struct gfs2_meta_header);
if (!height) {
error = gfs2_meta_inode_buffer(ip, &bh);
if (error)
return error;
dibh = bh;
top = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + mp->mp_list[0];
bottom = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + sdp->sd_diptrs;
} else {
error = gfs2_meta_indirect_buffer(ip, height, block, 0, &bh);
if (error)
return error;
top = (__be64 *)(bh->b_data + mh_size) +
(first ? mp->mp_list[height] : 0);
bottom = (__be64 *)(bh->b_data + mh_size) + sdp->sd_inptrs;
}
error = bc(ip, dibh, bh, top, bottom, height, data);
if (error)
goto out;
if (height < ip->i_height - 1)
for (; top < bottom; top++, first = 0) {
if (!*top)
continue;
bn = be64_to_cpu(*top);
error = recursive_scan(ip, dibh, mp, height + 1, bn,
first, bc, data);
if (error)
break;
}
out:
brelse(bh);
return error;
}
/**
* do_strip - Look for a layer a particular layer of the file and strip it off
* @ip: the inode
* @dibh: the dinode buffer
* @bh: A buffer of pointers
* @top: The first pointer in the buffer
* @bottom: One more than the last pointer
* @height: the height this buffer is at
* @data: a pointer to a struct strip_mine
*
* Returns: errno
*/
static int do_strip(struct gfs2_inode *ip, struct buffer_head *dibh,
struct buffer_head *bh, __be64 *top, __be64 *bottom,
unsigned int height, void *data)
{
struct strip_mine *sm = data;
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_rgrp_list rlist;
u64 bn, bstart;
u32 blen;
__be64 *p;
unsigned int rg_blocks = 0;
int metadata;
unsigned int revokes = 0;
int x;
int error;
if (!*top)
sm->sm_first = 0;
if (height != sm->sm_height)
return 0;
if (sm->sm_first) {
top++;
sm->sm_first = 0;
}
metadata = (height != ip->i_height - 1);
if (metadata)
revokes = (height) ? sdp->sd_inptrs : sdp->sd_diptrs;
error = gfs2_rindex_hold(sdp, &ip->i_alloc->al_ri_gh);
if (error)
return error;
memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
bstart = 0;
blen = 0;
for (p = top; p < bottom; p++) {
if (!*p)
continue;
bn = be64_to_cpu(*p);
if (bstart + blen == bn)
blen++;
else {
if (bstart)
gfs2_rlist_add(sdp, &rlist, bstart);
bstart = bn;
blen = 1;
}
}
if (bstart)
gfs2_rlist_add(sdp, &rlist, bstart);
else
goto out; /* Nothing to do */
gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE);
for (x = 0; x < rlist.rl_rgrps; x++) {
struct gfs2_rgrpd *rgd;
rgd = rlist.rl_ghs[x].gh_gl->gl_object;
rg_blocks += rgd->rd_length;
}
error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
if (error)
goto out_rlist;
error = gfs2_trans_begin(sdp, rg_blocks + RES_DINODE +
RES_INDIRECT + RES_STATFS + RES_QUOTA,
revokes);
if (error)
goto out_rg_gunlock;
down_write(&ip->i_rw_mutex);
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_trans_add_bh(ip->i_gl, bh, 1);
bstart = 0;
blen = 0;
for (p = top; p < bottom; p++) {
if (!*p)
continue;
bn = be64_to_cpu(*p);
if (bstart + blen == bn)
blen++;
else {
if (bstart) {
if (metadata)
gfs2_free_meta(ip, bstart, blen);
else
gfs2_free_data(ip, bstart, blen);
}
bstart = bn;
blen = 1;
}
*p = 0;
if (!ip->i_di.di_blocks)
gfs2_consist_inode(ip);
ip->i_di.di_blocks--;
gfs2_set_inode_blocks(&ip->i_inode);
}
if (bstart) {
if (metadata)
gfs2_free_meta(ip, bstart, blen);
else
gfs2_free_data(ip, bstart, blen);
}
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
gfs2_dinode_out(ip, dibh->b_data);
up_write(&ip->i_rw_mutex);
gfs2_trans_end(sdp);
out_rg_gunlock:
gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
out_rlist:
gfs2_rlist_free(&rlist);
out:
gfs2_glock_dq_uninit(&ip->i_alloc->al_ri_gh);
return error;
}
/**
* do_grow - Make a file look bigger than it is
* @ip: the inode
* @size: the size to set the file to
*
* Called with an exclusive lock on @ip.
*
* Returns: errno
*/
static int do_grow(struct gfs2_inode *ip, u64 size)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_alloc *al;
struct buffer_head *dibh;
int error;
al = gfs2_alloc_get(ip);
error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
if (error)
goto out;
error = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid);
if (error)
goto out_gunlock_q;
al->al_requested = sdp->sd_max_height + RES_DATA;
error = gfs2_inplace_reserve(ip);
if (error)
goto out_gunlock_q;
error = gfs2_trans_begin(sdp,
sdp->sd_max_height + al->al_rgd->rd_length +
RES_JDATA + RES_DINODE + RES_STATFS + RES_QUOTA, 0);
if (error)
goto out_ipres;
if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
const u64 *arr = sdp->sd_heightsize;
if (gfs2_is_stuffed(ip)) {
error = gfs2_unstuff_dinode(ip, NULL);
if (error)
goto out_end_trans;
}
down_write(&ip->i_rw_mutex);
if (size > arr[ip->i_height]) {
u8 height = ip->i_height;
while(size > arr[height])
height++;
error = build_height(&ip->i_inode, height);
}
up_write(&ip->i_rw_mutex);
if (error)
goto out_end_trans;
}
ip->i_di.di_size = size;
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto out_end_trans;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
out_end_trans:
gfs2_trans_end(sdp);
out_ipres:
gfs2_inplace_release(ip);
out_gunlock_q:
gfs2_quota_unlock(ip);
out:
gfs2_alloc_put(ip);
return error;
}
/**
* gfs2_block_truncate_page - Deal with zeroing out data for truncate
*
* This is partly borrowed from ext3.
*/
static int gfs2_block_truncate_page(struct address_space *mapping)
{
struct inode *inode = mapping->host;
struct gfs2_inode *ip = GFS2_I(inode);
loff_t from = inode->i_size;
unsigned long index = from >> PAGE_CACHE_SHIFT;
unsigned offset = from & (PAGE_CACHE_SIZE-1);
unsigned blocksize, iblock, length, pos;
struct buffer_head *bh;
struct page *page;
int err;
page = grab_cache_page(mapping, index);
if (!page)
return 0;
blocksize = inode->i_sb->s_blocksize;
length = blocksize - (offset & (blocksize - 1));
iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
if (!page_has_buffers(page))
create_empty_buffers(page, blocksize, 0);
/* Find the buffer that contains "offset" */
bh = page_buffers(page);
pos = blocksize;
while (offset >= pos) {
bh = bh->b_this_page;
iblock++;
pos += blocksize;
}
err = 0;
if (!buffer_mapped(bh)) {
gfs2_block_map(inode, iblock, bh, 0);
/* unmapped? It's a hole - nothing to do */
if (!buffer_mapped(bh))
goto unlock;
}
/* Ok, it's mapped. Make sure it's up-to-date */
if (PageUptodate(page))
set_buffer_uptodate(bh);
if (!buffer_uptodate(bh)) {
err = -EIO;
ll_rw_block(READ, 1, &bh);
wait_on_buffer(bh);
/* Uhhuh. Read error. Complain and punt. */
if (!buffer_uptodate(bh))
goto unlock;
err = 0;
}
if (!gfs2_is_writeback(ip))
gfs2_trans_add_bh(ip->i_gl, bh, 0);
zero_user(page, offset, length);
unlock:
unlock_page(page);
page_cache_release(page);
return err;
}
static int trunc_start(struct gfs2_inode *ip, u64 size)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct buffer_head *dibh;
int journaled = gfs2_is_jdata(ip);
int error;
error = gfs2_trans_begin(sdp,
RES_DINODE + (journaled ? RES_JDATA : 0), 0);
if (error)
return error;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto out;
if (gfs2_is_stuffed(ip)) {
ip->i_di.di_size = size;
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + size);
error = 1;
} else {
if (size & (u64)(sdp->sd_sb.sb_bsize - 1))
error = gfs2_block_truncate_page(ip->i_inode.i_mapping);
if (!error) {
ip->i_di.di_size = size;
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
ip->i_di.di_flags |= GFS2_DIF_TRUNC_IN_PROG;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
}
}
brelse(dibh);
out:
gfs2_trans_end(sdp);
return error;
}
static int trunc_dealloc(struct gfs2_inode *ip, u64 size)
{
unsigned int height = ip->i_height;
u64 lblock;
struct metapath mp;
int error;
if (!size)
lblock = 0;
else
lblock = (size - 1) >> GFS2_SB(&ip->i_inode)->sd_sb.sb_bsize_shift;
find_metapath(ip, lblock, &mp);
gfs2_alloc_get(ip);
error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
if (error)
goto out;
while (height--) {
struct strip_mine sm;
sm.sm_first = !!size;
sm.sm_height = height;
error = recursive_scan(ip, NULL, &mp, 0, 0, 1, do_strip, &sm);
if (error)
break;
}
gfs2_quota_unhold(ip);
out:
gfs2_alloc_put(ip);
return error;
}
static int trunc_end(struct gfs2_inode *ip)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct buffer_head *dibh;
int error;
error = gfs2_trans_begin(sdp, RES_DINODE, 0);
if (error)
return error;