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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * NILFS segment usage file.
4 *
5 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
6 *
7 * Written by Koji Sato.
8 * Revised by Ryusuke Konishi.
9 */
10
11#include <linux/kernel.h>
12#include <linux/fs.h>
13#include <linux/string.h>
14#include <linux/buffer_head.h>
15#include <linux/errno.h>
16#include "mdt.h"
17#include "sufile.h"
18
19#include <trace/events/nilfs2.h>
20
21/**
22 * struct nilfs_sufile_info - on-memory private data of sufile
23 * @mi: on-memory private data of metadata file
24 * @ncleansegs: number of clean segments
25 * @allocmin: lower limit of allocatable segment range
26 * @allocmax: upper limit of allocatable segment range
27 */
28struct nilfs_sufile_info {
29 struct nilfs_mdt_info mi;
30 unsigned long ncleansegs;/* number of clean segments */
31 __u64 allocmin; /* lower limit of allocatable segment range */
32 __u64 allocmax; /* upper limit of allocatable segment range */
33};
34
35static inline struct nilfs_sufile_info *NILFS_SUI(struct inode *sufile)
36{
37 return (struct nilfs_sufile_info *)NILFS_MDT(sufile);
38}
39
40static inline unsigned long
41nilfs_sufile_segment_usages_per_block(const struct inode *sufile)
42{
43 return NILFS_MDT(sufile)->mi_entries_per_block;
44}
45
46static unsigned long
47nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum)
48{
49 __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
50
51 do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
52 return (unsigned long)t;
53}
54
55static unsigned long
56nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum)
57{
58 __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
59
60 return do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
61}
62
63static unsigned long
64nilfs_sufile_segment_usages_in_block(const struct inode *sufile, __u64 curr,
65 __u64 max)
66{
67 return min_t(unsigned long,
68 nilfs_sufile_segment_usages_per_block(sufile) -
69 nilfs_sufile_get_offset(sufile, curr),
70 max - curr + 1);
71}
72
73static struct nilfs_segment_usage *
74nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum,
75 struct buffer_head *bh, void *kaddr)
76{
77 return kaddr + bh_offset(bh) +
78 nilfs_sufile_get_offset(sufile, segnum) *
79 NILFS_MDT(sufile)->mi_entry_size;
80}
81
82static inline int nilfs_sufile_get_header_block(struct inode *sufile,
83 struct buffer_head **bhp)
84{
85 return nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);
86}
87
88static inline int
89nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,
90 int create, struct buffer_head **bhp)
91{
92 return nilfs_mdt_get_block(sufile,
93 nilfs_sufile_get_blkoff(sufile, segnum),
94 create, NULL, bhp);
95}
96
97static int nilfs_sufile_delete_segment_usage_block(struct inode *sufile,
98 __u64 segnum)
99{
100 return nilfs_mdt_delete_block(sufile,
101 nilfs_sufile_get_blkoff(sufile, segnum));
102}
103
104static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,
105 u64 ncleanadd, u64 ndirtyadd)
106{
107 struct nilfs_sufile_header *header;
108 void *kaddr;
109
110 kaddr = kmap_atomic(header_bh->b_page);
111 header = kaddr + bh_offset(header_bh);
112 le64_add_cpu(&header->sh_ncleansegs, ncleanadd);
113 le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);
114 kunmap_atomic(kaddr);
115
116 mark_buffer_dirty(header_bh);
117}
118
119/**
120 * nilfs_sufile_get_ncleansegs - return the number of clean segments
121 * @sufile: inode of segment usage file
122 */
123unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile)
124{
125 return NILFS_SUI(sufile)->ncleansegs;
126}
127
128/**
129 * nilfs_sufile_updatev - modify multiple segment usages at a time
130 * @sufile: inode of segment usage file
131 * @segnumv: array of segment numbers
132 * @nsegs: size of @segnumv array
133 * @create: creation flag
134 * @ndone: place to store number of modified segments on @segnumv
135 * @dofunc: primitive operation for the update
136 *
137 * Description: nilfs_sufile_updatev() repeatedly calls @dofunc
138 * against the given array of segments. The @dofunc is called with
139 * buffers of a header block and the sufile block in which the target
140 * segment usage entry is contained. If @ndone is given, the number
141 * of successfully modified segments from the head is stored in the
142 * place @ndone points to.
143 *
144 * Return Value: On success, zero is returned. On error, one of the
145 * following negative error codes is returned.
146 *
147 * %-EIO - I/O error.
148 *
149 * %-ENOMEM - Insufficient amount of memory available.
150 *
151 * %-ENOENT - Given segment usage is in hole block (may be returned if
152 * @create is zero)
153 *
154 * %-EINVAL - Invalid segment usage number
155 */
156int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs,
157 int create, size_t *ndone,
158 void (*dofunc)(struct inode *, __u64,
159 struct buffer_head *,
160 struct buffer_head *))
161{
162 struct buffer_head *header_bh, *bh;
163 unsigned long blkoff, prev_blkoff;
164 __u64 *seg;
165 size_t nerr = 0, n = 0;
166 int ret = 0;
167
168 if (unlikely(nsegs == 0))
169 goto out;
170
171 down_write(&NILFS_MDT(sufile)->mi_sem);
172 for (seg = segnumv; seg < segnumv + nsegs; seg++) {
173 if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) {
174 nilfs_warn(sufile->i_sb,
175 "%s: invalid segment number: %llu",
176 __func__, (unsigned long long)*seg);
177 nerr++;
178 }
179 }
180 if (nerr > 0) {
181 ret = -EINVAL;
182 goto out_sem;
183 }
184
185 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
186 if (ret < 0)
187 goto out_sem;
188
189 seg = segnumv;
190 blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
191 ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
192 if (ret < 0)
193 goto out_header;
194
195 for (;;) {
196 dofunc(sufile, *seg, header_bh, bh);
197
198 if (++seg >= segnumv + nsegs)
199 break;
200 prev_blkoff = blkoff;
201 blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
202 if (blkoff == prev_blkoff)
203 continue;
204
205 /* get different block */
206 brelse(bh);
207 ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
208 if (unlikely(ret < 0))
209 goto out_header;
210 }
211 brelse(bh);
212
213 out_header:
214 n = seg - segnumv;
215 brelse(header_bh);
216 out_sem:
217 up_write(&NILFS_MDT(sufile)->mi_sem);
218 out:
219 if (ndone)
220 *ndone = n;
221 return ret;
222}
223
224int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create,
225 void (*dofunc)(struct inode *, __u64,
226 struct buffer_head *,
227 struct buffer_head *))
228{
229 struct buffer_head *header_bh, *bh;
230 int ret;
231
232 if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
233 nilfs_warn(sufile->i_sb, "%s: invalid segment number: %llu",
234 __func__, (unsigned long long)segnum);
235 return -EINVAL;
236 }
237 down_write(&NILFS_MDT(sufile)->mi_sem);
238
239 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
240 if (ret < 0)
241 goto out_sem;
242
243 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh);
244 if (!ret) {
245 dofunc(sufile, segnum, header_bh, bh);
246 brelse(bh);
247 }
248 brelse(header_bh);
249
250 out_sem:
251 up_write(&NILFS_MDT(sufile)->mi_sem);
252 return ret;
253}
254
255/**
256 * nilfs_sufile_set_alloc_range - limit range of segment to be allocated
257 * @sufile: inode of segment usage file
258 * @start: minimum segment number of allocatable region (inclusive)
259 * @end: maximum segment number of allocatable region (inclusive)
260 *
261 * Return Value: On success, 0 is returned. On error, one of the
262 * following negative error codes is returned.
263 *
264 * %-ERANGE - invalid segment region
265 */
266int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end)
267{
268 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
269 __u64 nsegs;
270 int ret = -ERANGE;
271
272 down_write(&NILFS_MDT(sufile)->mi_sem);
273 nsegs = nilfs_sufile_get_nsegments(sufile);
274
275 if (start <= end && end < nsegs) {
276 sui->allocmin = start;
277 sui->allocmax = end;
278 ret = 0;
279 }
280 up_write(&NILFS_MDT(sufile)->mi_sem);
281 return ret;
282}
283
284/**
285 * nilfs_sufile_alloc - allocate a segment
286 * @sufile: inode of segment usage file
287 * @segnump: pointer to segment number
288 *
289 * Description: nilfs_sufile_alloc() allocates a clean segment.
290 *
291 * Return Value: On success, 0 is returned and the segment number of the
292 * allocated segment is stored in the place pointed by @segnump. On error, one
293 * of the following negative error codes is returned.
294 *
295 * %-EIO - I/O error.
296 *
297 * %-ENOMEM - Insufficient amount of memory available.
298 *
299 * %-ENOSPC - No clean segment left.
300 */
301int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
302{
303 struct buffer_head *header_bh, *su_bh;
304 struct nilfs_sufile_header *header;
305 struct nilfs_segment_usage *su;
306 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
307 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
308 __u64 segnum, maxsegnum, last_alloc;
309 void *kaddr;
310 unsigned long nsegments, nsus, cnt;
311 int ret, j;
312
313 down_write(&NILFS_MDT(sufile)->mi_sem);
314
315 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
316 if (ret < 0)
317 goto out_sem;
318 kaddr = kmap_atomic(header_bh->b_page);
319 header = kaddr + bh_offset(header_bh);
320 last_alloc = le64_to_cpu(header->sh_last_alloc);
321 kunmap_atomic(kaddr);
322
323 nsegments = nilfs_sufile_get_nsegments(sufile);
324 maxsegnum = sui->allocmax;
325 segnum = last_alloc + 1;
326 if (segnum < sui->allocmin || segnum > sui->allocmax)
327 segnum = sui->allocmin;
328
329 for (cnt = 0; cnt < nsegments; cnt += nsus) {
330 if (segnum > maxsegnum) {
331 if (cnt < sui->allocmax - sui->allocmin + 1) {
332 /*
333 * wrap around in the limited region.
334 * if allocation started from
335 * sui->allocmin, this never happens.
336 */
337 segnum = sui->allocmin;
338 maxsegnum = last_alloc;
339 } else if (segnum > sui->allocmin &&
340 sui->allocmax + 1 < nsegments) {
341 segnum = sui->allocmax + 1;
342 maxsegnum = nsegments - 1;
343 } else if (sui->allocmin > 0) {
344 segnum = 0;
345 maxsegnum = sui->allocmin - 1;
346 } else {
347 break; /* never happens */
348 }
349 }
350 trace_nilfs2_segment_usage_check(sufile, segnum, cnt);
351 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
352 &su_bh);
353 if (ret < 0)
354 goto out_header;
355 kaddr = kmap_atomic(su_bh->b_page);
356 su = nilfs_sufile_block_get_segment_usage(
357 sufile, segnum, su_bh, kaddr);
358
359 nsus = nilfs_sufile_segment_usages_in_block(
360 sufile, segnum, maxsegnum);
361 for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
362 if (!nilfs_segment_usage_clean(su))
363 continue;
364 /* found a clean segment */
365 nilfs_segment_usage_set_dirty(su);
366 kunmap_atomic(kaddr);
367
368 kaddr = kmap_atomic(header_bh->b_page);
369 header = kaddr + bh_offset(header_bh);
370 le64_add_cpu(&header->sh_ncleansegs, -1);
371 le64_add_cpu(&header->sh_ndirtysegs, 1);
372 header->sh_last_alloc = cpu_to_le64(segnum);
373 kunmap_atomic(kaddr);
374
375 sui->ncleansegs--;
376 mark_buffer_dirty(header_bh);
377 mark_buffer_dirty(su_bh);
378 nilfs_mdt_mark_dirty(sufile);
379 brelse(su_bh);
380 *segnump = segnum;
381
382 trace_nilfs2_segment_usage_allocated(sufile, segnum);
383
384 goto out_header;
385 }
386
387 kunmap_atomic(kaddr);
388 brelse(su_bh);
389 }
390
391 /* no segments left */
392 ret = -ENOSPC;
393
394 out_header:
395 brelse(header_bh);
396
397 out_sem:
398 up_write(&NILFS_MDT(sufile)->mi_sem);
399 return ret;
400}
401
402void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,
403 struct buffer_head *header_bh,
404 struct buffer_head *su_bh)
405{
406 struct nilfs_segment_usage *su;
407 void *kaddr;
408
409 kaddr = kmap_atomic(su_bh->b_page);
410 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
411 if (unlikely(!nilfs_segment_usage_clean(su))) {
412 nilfs_warn(sufile->i_sb, "%s: segment %llu must be clean",
413 __func__, (unsigned long long)segnum);
414 kunmap_atomic(kaddr);
415 return;
416 }
417 nilfs_segment_usage_set_dirty(su);
418 kunmap_atomic(kaddr);
419
420 nilfs_sufile_mod_counter(header_bh, -1, 1);
421 NILFS_SUI(sufile)->ncleansegs--;
422
423 mark_buffer_dirty(su_bh);
424 nilfs_mdt_mark_dirty(sufile);
425}
426
427void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,
428 struct buffer_head *header_bh,
429 struct buffer_head *su_bh)
430{
431 struct nilfs_segment_usage *su;
432 void *kaddr;
433 int clean, dirty;
434
435 kaddr = kmap_atomic(su_bh->b_page);
436 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
437 if (su->su_flags == cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY)) &&
438 su->su_nblocks == cpu_to_le32(0)) {
439 kunmap_atomic(kaddr);
440 return;
441 }
442 clean = nilfs_segment_usage_clean(su);
443 dirty = nilfs_segment_usage_dirty(su);
444
445 /* make the segment garbage */
446 su->su_lastmod = cpu_to_le64(0);
447 su->su_nblocks = cpu_to_le32(0);
448 su->su_flags = cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY));
449 kunmap_atomic(kaddr);
450
451 nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);
452 NILFS_SUI(sufile)->ncleansegs -= clean;
453
454 mark_buffer_dirty(su_bh);
455 nilfs_mdt_mark_dirty(sufile);
456}
457
458void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,
459 struct buffer_head *header_bh,
460 struct buffer_head *su_bh)
461{
462 struct nilfs_segment_usage *su;
463 void *kaddr;
464 int sudirty;
465
466 kaddr = kmap_atomic(su_bh->b_page);
467 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
468 if (nilfs_segment_usage_clean(su)) {
469 nilfs_warn(sufile->i_sb, "%s: segment %llu is already clean",
470 __func__, (unsigned long long)segnum);
471 kunmap_atomic(kaddr);
472 return;
473 }
474 WARN_ON(nilfs_segment_usage_error(su));
475 WARN_ON(!nilfs_segment_usage_dirty(su));
476
477 sudirty = nilfs_segment_usage_dirty(su);
478 nilfs_segment_usage_set_clean(su);
479 kunmap_atomic(kaddr);
480 mark_buffer_dirty(su_bh);
481
482 nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);
483 NILFS_SUI(sufile)->ncleansegs++;
484
485 nilfs_mdt_mark_dirty(sufile);
486
487 trace_nilfs2_segment_usage_freed(sufile, segnum);
488}
489
490/**
491 * nilfs_sufile_mark_dirty - mark the buffer having a segment usage dirty
492 * @sufile: inode of segment usage file
493 * @segnum: segment number
494 */
495int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)
496{
497 struct buffer_head *bh;
498 void *kaddr;
499 struct nilfs_segment_usage *su;
500 int ret;
501
502 down_write(&NILFS_MDT(sufile)->mi_sem);
503 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
504 if (!ret) {
505 mark_buffer_dirty(bh);
506 nilfs_mdt_mark_dirty(sufile);
507 kaddr = kmap_atomic(bh->b_page);
508 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);
509 nilfs_segment_usage_set_dirty(su);
510 kunmap_atomic(kaddr);
511 brelse(bh);
512 }
513 up_write(&NILFS_MDT(sufile)->mi_sem);
514 return ret;
515}
516
517/**
518 * nilfs_sufile_set_segment_usage - set usage of a segment
519 * @sufile: inode of segment usage file
520 * @segnum: segment number
521 * @nblocks: number of live blocks in the segment
522 * @modtime: modification time (option)
523 */
524int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
525 unsigned long nblocks, time64_t modtime)
526{
527 struct buffer_head *bh;
528 struct nilfs_segment_usage *su;
529 void *kaddr;
530 int ret;
531
532 down_write(&NILFS_MDT(sufile)->mi_sem);
533 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
534 if (ret < 0)
535 goto out_sem;
536
537 kaddr = kmap_atomic(bh->b_page);
538 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);
539 WARN_ON(nilfs_segment_usage_error(su));
540 if (modtime)
541 su->su_lastmod = cpu_to_le64(modtime);
542 su->su_nblocks = cpu_to_le32(nblocks);
543 kunmap_atomic(kaddr);
544
545 mark_buffer_dirty(bh);
546 nilfs_mdt_mark_dirty(sufile);
547 brelse(bh);
548
549 out_sem:
550 up_write(&NILFS_MDT(sufile)->mi_sem);
551 return ret;
552}
553
554/**
555 * nilfs_sufile_get_stat - get segment usage statistics
556 * @sufile: inode of segment usage file
557 * @sustat: pointer to a structure of segment usage statistics
558 *
559 * Description: nilfs_sufile_get_stat() returns information about segment
560 * usage.
561 *
562 * Return Value: On success, 0 is returned, and segment usage information is
563 * stored in the place pointed by @sustat. On error, one of the following
564 * negative error codes is returned.
565 *
566 * %-EIO - I/O error.
567 *
568 * %-ENOMEM - Insufficient amount of memory available.
569 */
570int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat)
571{
572 struct buffer_head *header_bh;
573 struct nilfs_sufile_header *header;
574 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
575 void *kaddr;
576 int ret;
577
578 down_read(&NILFS_MDT(sufile)->mi_sem);
579
580 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
581 if (ret < 0)
582 goto out_sem;
583
584 kaddr = kmap_atomic(header_bh->b_page);
585 header = kaddr + bh_offset(header_bh);
586 sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile);
587 sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs);
588 sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs);
589 sustat->ss_ctime = nilfs->ns_ctime;
590 sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime;
591 spin_lock(&nilfs->ns_last_segment_lock);
592 sustat->ss_prot_seq = nilfs->ns_prot_seq;
593 spin_unlock(&nilfs->ns_last_segment_lock);
594 kunmap_atomic(kaddr);
595 brelse(header_bh);
596
597 out_sem:
598 up_read(&NILFS_MDT(sufile)->mi_sem);
599 return ret;
600}
601
602void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
603 struct buffer_head *header_bh,
604 struct buffer_head *su_bh)
605{
606 struct nilfs_segment_usage *su;
607 void *kaddr;
608 int suclean;
609
610 kaddr = kmap_atomic(su_bh->b_page);
611 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
612 if (nilfs_segment_usage_error(su)) {
613 kunmap_atomic(kaddr);
614 return;
615 }
616 suclean = nilfs_segment_usage_clean(su);
617 nilfs_segment_usage_set_error(su);
618 kunmap_atomic(kaddr);
619
620 if (suclean) {
621 nilfs_sufile_mod_counter(header_bh, -1, 0);
622 NILFS_SUI(sufile)->ncleansegs--;
623 }
624 mark_buffer_dirty(su_bh);
625 nilfs_mdt_mark_dirty(sufile);
626}
627
628/**
629 * nilfs_sufile_truncate_range - truncate range of segment array
630 * @sufile: inode of segment usage file
631 * @start: start segment number (inclusive)
632 * @end: end segment number (inclusive)
633 *
634 * Return Value: On success, 0 is returned. On error, one of the
635 * following negative error codes is returned.
636 *
637 * %-EIO - I/O error.
638 *
639 * %-ENOMEM - Insufficient amount of memory available.
640 *
641 * %-EINVAL - Invalid number of segments specified
642 *
643 * %-EBUSY - Dirty or active segments are present in the range
644 */
645static int nilfs_sufile_truncate_range(struct inode *sufile,
646 __u64 start, __u64 end)
647{
648 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
649 struct buffer_head *header_bh;
650 struct buffer_head *su_bh;
651 struct nilfs_segment_usage *su, *su2;
652 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
653 unsigned long segusages_per_block;
654 unsigned long nsegs, ncleaned;
655 __u64 segnum;
656 void *kaddr;
657 ssize_t n, nc;
658 int ret;
659 int j;
660
661 nsegs = nilfs_sufile_get_nsegments(sufile);
662
663 ret = -EINVAL;
664 if (start > end || start >= nsegs)
665 goto out;
666
667 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
668 if (ret < 0)
669 goto out;
670
671 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
672 ncleaned = 0;
673
674 for (segnum = start; segnum <= end; segnum += n) {
675 n = min_t(unsigned long,
676 segusages_per_block -
677 nilfs_sufile_get_offset(sufile, segnum),
678 end - segnum + 1);
679 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
680 &su_bh);
681 if (ret < 0) {
682 if (ret != -ENOENT)
683 goto out_header;
684 /* hole */
685 continue;
686 }
687 kaddr = kmap_atomic(su_bh->b_page);
688 su = nilfs_sufile_block_get_segment_usage(
689 sufile, segnum, su_bh, kaddr);
690 su2 = su;
691 for (j = 0; j < n; j++, su = (void *)su + susz) {
692 if ((le32_to_cpu(su->su_flags) &
693 ~BIT(NILFS_SEGMENT_USAGE_ERROR)) ||
694 nilfs_segment_is_active(nilfs, segnum + j)) {
695 ret = -EBUSY;
696 kunmap_atomic(kaddr);
697 brelse(su_bh);
698 goto out_header;
699 }
700 }
701 nc = 0;
702 for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) {
703 if (nilfs_segment_usage_error(su)) {
704 nilfs_segment_usage_set_clean(su);
705 nc++;
706 }
707 }
708 kunmap_atomic(kaddr);
709 if (nc > 0) {
710 mark_buffer_dirty(su_bh);
711 ncleaned += nc;
712 }
713 brelse(su_bh);
714
715 if (n == segusages_per_block) {
716 /* make hole */
717 nilfs_sufile_delete_segment_usage_block(sufile, segnum);
718 }
719 }
720 ret = 0;
721
722out_header:
723 if (ncleaned > 0) {
724 NILFS_SUI(sufile)->ncleansegs += ncleaned;
725 nilfs_sufile_mod_counter(header_bh, ncleaned, 0);
726 nilfs_mdt_mark_dirty(sufile);
727 }
728 brelse(header_bh);
729out:
730 return ret;
731}
732
733/**
734 * nilfs_sufile_resize - resize segment array
735 * @sufile: inode of segment usage file
736 * @newnsegs: new number of segments
737 *
738 * Return Value: On success, 0 is returned. On error, one of the
739 * following negative error codes is returned.
740 *
741 * %-EIO - I/O error.
742 *
743 * %-ENOMEM - Insufficient amount of memory available.
744 *
745 * %-ENOSPC - Enough free space is not left for shrinking
746 *
747 * %-EBUSY - Dirty or active segments exist in the region to be truncated
748 */
749int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs)
750{
751 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
752 struct buffer_head *header_bh;
753 struct nilfs_sufile_header *header;
754 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
755 void *kaddr;
756 unsigned long nsegs, nrsvsegs;
757 int ret = 0;
758
759 down_write(&NILFS_MDT(sufile)->mi_sem);
760
761 nsegs = nilfs_sufile_get_nsegments(sufile);
762 if (nsegs == newnsegs)
763 goto out;
764
765 ret = -ENOSPC;
766 nrsvsegs = nilfs_nrsvsegs(nilfs, newnsegs);
767 if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs)
768 goto out;
769
770 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
771 if (ret < 0)
772 goto out;
773
774 if (newnsegs > nsegs) {
775 sui->ncleansegs += newnsegs - nsegs;
776 } else /* newnsegs < nsegs */ {
777 ret = nilfs_sufile_truncate_range(sufile, newnsegs, nsegs - 1);
778 if (ret < 0)
779 goto out_header;
780
781 sui->ncleansegs -= nsegs - newnsegs;
782 }
783
784 kaddr = kmap_atomic(header_bh->b_page);
785 header = kaddr + bh_offset(header_bh);
786 header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs);
787 kunmap_atomic(kaddr);
788
789 mark_buffer_dirty(header_bh);
790 nilfs_mdt_mark_dirty(sufile);
791 nilfs_set_nsegments(nilfs, newnsegs);
792
793out_header:
794 brelse(header_bh);
795out:
796 up_write(&NILFS_MDT(sufile)->mi_sem);
797 return ret;
798}
799
800/**
801 * nilfs_sufile_get_suinfo -
802 * @sufile: inode of segment usage file
803 * @segnum: segment number to start looking
804 * @buf: array of suinfo
805 * @sisz: byte size of suinfo
806 * @nsi: size of suinfo array
807 *
808 * Description:
809 *
810 * Return Value: On success, 0 is returned and .... On error, one of the
811 * following negative error codes is returned.
812 *
813 * %-EIO - I/O error.
814 *
815 * %-ENOMEM - Insufficient amount of memory available.
816 */
817ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
818 unsigned int sisz, size_t nsi)
819{
820 struct buffer_head *su_bh;
821 struct nilfs_segment_usage *su;
822 struct nilfs_suinfo *si = buf;
823 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
824 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
825 void *kaddr;
826 unsigned long nsegs, segusages_per_block;
827 ssize_t n;
828 int ret, i, j;
829
830 down_read(&NILFS_MDT(sufile)->mi_sem);
831
832 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
833 nsegs = min_t(unsigned long,
834 nilfs_sufile_get_nsegments(sufile) - segnum,
835 nsi);
836 for (i = 0; i < nsegs; i += n, segnum += n) {
837 n = min_t(unsigned long,
838 segusages_per_block -
839 nilfs_sufile_get_offset(sufile, segnum),
840 nsegs - i);
841 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
842 &su_bh);
843 if (ret < 0) {
844 if (ret != -ENOENT)
845 goto out;
846 /* hole */
847 memset(si, 0, sisz * n);
848 si = (void *)si + sisz * n;
849 continue;
850 }
851
852 kaddr = kmap_atomic(su_bh->b_page);
853 su = nilfs_sufile_block_get_segment_usage(
854 sufile, segnum, su_bh, kaddr);
855 for (j = 0; j < n;
856 j++, su = (void *)su + susz, si = (void *)si + sisz) {
857 si->sui_lastmod = le64_to_cpu(su->su_lastmod);
858 si->sui_nblocks = le32_to_cpu(su->su_nblocks);
859 si->sui_flags = le32_to_cpu(su->su_flags) &
860 ~BIT(NILFS_SEGMENT_USAGE_ACTIVE);
861 if (nilfs_segment_is_active(nilfs, segnum + j))
862 si->sui_flags |=
863 BIT(NILFS_SEGMENT_USAGE_ACTIVE);
864 }
865 kunmap_atomic(kaddr);
866 brelse(su_bh);
867 }
868 ret = nsegs;
869
870 out:
871 up_read(&NILFS_MDT(sufile)->mi_sem);
872 return ret;
873}
874
875/**
876 * nilfs_sufile_set_suinfo - sets segment usage info
877 * @sufile: inode of segment usage file
878 * @buf: array of suinfo_update
879 * @supsz: byte size of suinfo_update
880 * @nsup: size of suinfo_update array
881 *
882 * Description: Takes an array of nilfs_suinfo_update structs and updates
883 * segment usage accordingly. Only the fields indicated by the sup_flags
884 * are updated.
885 *
886 * Return Value: On success, 0 is returned. On error, one of the
887 * following negative error codes is returned.
888 *
889 * %-EIO - I/O error.
890 *
891 * %-ENOMEM - Insufficient amount of memory available.
892 *
893 * %-EINVAL - Invalid values in input (segment number, flags or nblocks)
894 */
895ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf,
896 unsigned int supsz, size_t nsup)
897{
898 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
899 struct buffer_head *header_bh, *bh;
900 struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup;
901 struct nilfs_segment_usage *su;
902 void *kaddr;
903 unsigned long blkoff, prev_blkoff;
904 int cleansi, cleansu, dirtysi, dirtysu;
905 long ncleaned = 0, ndirtied = 0;
906 int ret = 0;
907
908 if (unlikely(nsup == 0))
909 return ret;
910
911 for (sup = buf; sup < supend; sup = (void *)sup + supsz) {
912 if (sup->sup_segnum >= nilfs->ns_nsegments
913 || (sup->sup_flags &
914 (~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS))
915 || (nilfs_suinfo_update_nblocks(sup) &&
916 sup->sup_sui.sui_nblocks >
917 nilfs->ns_blocks_per_segment))
918 return -EINVAL;
919 }
920
921 down_write(&NILFS_MDT(sufile)->mi_sem);
922
923 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
924 if (ret < 0)
925 goto out_sem;
926
927 sup = buf;
928 blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
929 ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
930 if (ret < 0)
931 goto out_header;
932
933 for (;;) {
934 kaddr = kmap_atomic(bh->b_page);
935 su = nilfs_sufile_block_get_segment_usage(
936 sufile, sup->sup_segnum, bh, kaddr);
937
938 if (nilfs_suinfo_update_lastmod(sup))
939 su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod);
940
941 if (nilfs_suinfo_update_nblocks(sup))
942 su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks);
943
944 if (nilfs_suinfo_update_flags(sup)) {
945 /*
946 * Active flag is a virtual flag projected by running
947 * nilfs kernel code - drop it not to write it to
948 * disk.
949 */
950 sup->sup_sui.sui_flags &=
951 ~BIT(NILFS_SEGMENT_USAGE_ACTIVE);
952
953 cleansi = nilfs_suinfo_clean(&sup->sup_sui);
954 cleansu = nilfs_segment_usage_clean(su);
955 dirtysi = nilfs_suinfo_dirty(&sup->sup_sui);
956 dirtysu = nilfs_segment_usage_dirty(su);
957
958 if (cleansi && !cleansu)
959 ++ncleaned;
960 else if (!cleansi && cleansu)
961 --ncleaned;
962
963 if (dirtysi && !dirtysu)
964 ++ndirtied;
965 else if (!dirtysi && dirtysu)
966 --ndirtied;
967
968 su->su_flags = cpu_to_le32(sup->sup_sui.sui_flags);
969 }
970
971 kunmap_atomic(kaddr);
972
973 sup = (void *)sup + supsz;
974 if (sup >= supend)
975 break;
976
977 prev_blkoff = blkoff;
978 blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
979 if (blkoff == prev_blkoff)
980 continue;
981
982 /* get different block */
983 mark_buffer_dirty(bh);
984 put_bh(bh);
985 ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
986 if (unlikely(ret < 0))
987 goto out_mark;
988 }
989 mark_buffer_dirty(bh);
990 put_bh(bh);
991
992 out_mark:
993 if (ncleaned || ndirtied) {
994 nilfs_sufile_mod_counter(header_bh, (u64)ncleaned,
995 (u64)ndirtied);
996 NILFS_SUI(sufile)->ncleansegs += ncleaned;
997 }
998 nilfs_mdt_mark_dirty(sufile);
999 out_header:
1000 put_bh(header_bh);
1001 out_sem:
1002 up_write(&NILFS_MDT(sufile)->mi_sem);
1003 return ret;
1004}
1005
1006/**
1007 * nilfs_sufile_trim_fs() - trim ioctl handle function
1008 * @sufile: inode of segment usage file
1009 * @range: fstrim_range structure
1010 *
1011 * start: First Byte to trim
1012 * len: number of Bytes to trim from start
1013 * minlen: minimum extent length in Bytes
1014 *
1015 * Decription: nilfs_sufile_trim_fs goes through all segments containing bytes
1016 * from start to start+len. start is rounded up to the next block boundary
1017 * and start+len is rounded down. For each clean segment blkdev_issue_discard
1018 * function is invoked.
1019 *
1020 * Return Value: On success, 0 is returned or negative error code, otherwise.
1021 */
1022int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)
1023{
1024 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
1025 struct buffer_head *su_bh;
1026 struct nilfs_segment_usage *su;
1027 void *kaddr;
1028 size_t n, i, susz = NILFS_MDT(sufile)->mi_entry_size;
1029 sector_t seg_start, seg_end, start_block, end_block;
1030 sector_t start = 0, nblocks = 0;
1031 u64 segnum, segnum_end, minlen, len, max_blocks, ndiscarded = 0;
1032 int ret = 0;
1033 unsigned int sects_per_block;
1034
1035 sects_per_block = (1 << nilfs->ns_blocksize_bits) /
1036 bdev_logical_block_size(nilfs->ns_bdev);
1037 len = range->len >> nilfs->ns_blocksize_bits;
1038 minlen = range->minlen >> nilfs->ns_blocksize_bits;
1039 max_blocks = ((u64)nilfs->ns_nsegments * nilfs->ns_blocks_per_segment);
1040
1041 if (!len || range->start >= max_blocks << nilfs->ns_blocksize_bits)
1042 return -EINVAL;
1043
1044 start_block = (range->start + nilfs->ns_blocksize - 1) >>
1045 nilfs->ns_blocksize_bits;
1046
1047 /*
1048 * range->len can be very large (actually, it is set to
1049 * ULLONG_MAX by default) - truncate upper end of the range
1050 * carefully so as not to overflow.
1051 */
1052 if (max_blocks - start_block < len)
1053 end_block = max_blocks - 1;
1054 else
1055 end_block = start_block + len - 1;
1056
1057 segnum = nilfs_get_segnum_of_block(nilfs, start_block);
1058 segnum_end = nilfs_get_segnum_of_block(nilfs, end_block);
1059
1060 down_read(&NILFS_MDT(sufile)->mi_sem);
1061
1062 while (segnum <= segnum_end) {
1063 n = nilfs_sufile_segment_usages_in_block(sufile, segnum,
1064 segnum_end);
1065
1066 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
1067 &su_bh);
1068 if (ret < 0) {
1069 if (ret != -ENOENT)
1070 goto out_sem;
1071 /* hole */
1072 segnum += n;
1073 continue;
1074 }
1075
1076 kaddr = kmap_atomic(su_bh->b_page);
1077 su = nilfs_sufile_block_get_segment_usage(sufile, segnum,
1078 su_bh, kaddr);
1079 for (i = 0; i < n; ++i, ++segnum, su = (void *)su + susz) {
1080 if (!nilfs_segment_usage_clean(su))
1081 continue;
1082
1083 nilfs_get_segment_range(nilfs, segnum, &seg_start,
1084 &seg_end);
1085
1086 if (!nblocks) {
1087 /* start new extent */
1088 start = seg_start;
1089 nblocks = seg_end - seg_start + 1;
1090 continue;
1091 }
1092
1093 if (start + nblocks == seg_start) {
1094 /* add to previous extent */
1095 nblocks += seg_end - seg_start + 1;
1096 continue;
1097 }
1098
1099 /* discard previous extent */
1100 if (start < start_block) {
1101 nblocks -= start_block - start;
1102 start = start_block;
1103 }
1104
1105 if (nblocks >= minlen) {
1106 kunmap_atomic(kaddr);
1107
1108 ret = blkdev_issue_discard(nilfs->ns_bdev,
1109 start * sects_per_block,
1110 nblocks * sects_per_block,
1111 GFP_NOFS);
1112 if (ret < 0) {
1113 put_bh(su_bh);
1114 goto out_sem;
1115 }
1116
1117 ndiscarded += nblocks;
1118 kaddr = kmap_atomic(su_bh->b_page);
1119 su = nilfs_sufile_block_get_segment_usage(
1120 sufile, segnum, su_bh, kaddr);
1121 }
1122
1123 /* start new extent */
1124 start = seg_start;
1125 nblocks = seg_end - seg_start + 1;
1126 }
1127 kunmap_atomic(kaddr);
1128 put_bh(su_bh);
1129 }
1130
1131
1132 if (nblocks) {
1133 /* discard last extent */
1134 if (start < start_block) {
1135 nblocks -= start_block - start;
1136 start = start_block;
1137 }
1138 if (start + nblocks > end_block + 1)
1139 nblocks = end_block - start + 1;
1140
1141 if (nblocks >= minlen) {
1142 ret = blkdev_issue_discard(nilfs->ns_bdev,
1143 start * sects_per_block,
1144 nblocks * sects_per_block,
1145 GFP_NOFS);
1146 if (!ret)
1147 ndiscarded += nblocks;
1148 }
1149 }
1150
1151out_sem:
1152 up_read(&NILFS_MDT(sufile)->mi_sem);
1153
1154 range->len = ndiscarded << nilfs->ns_blocksize_bits;
1155 return ret;
1156}
1157
1158/**
1159 * nilfs_sufile_read - read or get sufile inode
1160 * @sb: super block instance
1161 * @susize: size of a segment usage entry
1162 * @raw_inode: on-disk sufile inode
1163 * @inodep: buffer to store the inode
1164 */
1165int nilfs_sufile_read(struct super_block *sb, size_t susize,
1166 struct nilfs_inode *raw_inode, struct inode **inodep)
1167{
1168 struct inode *sufile;
1169 struct nilfs_sufile_info *sui;
1170 struct buffer_head *header_bh;
1171 struct nilfs_sufile_header *header;
1172 void *kaddr;
1173 int err;
1174
1175 if (susize > sb->s_blocksize) {
1176 nilfs_err(sb, "too large segment usage size: %zu bytes",
1177 susize);
1178 return -EINVAL;
1179 } else if (susize < NILFS_MIN_SEGMENT_USAGE_SIZE) {
1180 nilfs_err(sb, "too small segment usage size: %zu bytes",
1181 susize);
1182 return -EINVAL;
1183 }
1184
1185 sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO);
1186 if (unlikely(!sufile))
1187 return -ENOMEM;
1188 if (!(sufile->i_state & I_NEW))
1189 goto out;
1190
1191 err = nilfs_mdt_init(sufile, NILFS_MDT_GFP, sizeof(*sui));
1192 if (err)
1193 goto failed;
1194
1195 nilfs_mdt_set_entry_size(sufile, susize,
1196 sizeof(struct nilfs_sufile_header));
1197
1198 err = nilfs_read_inode_common(sufile, raw_inode);
1199 if (err)
1200 goto failed;
1201
1202 err = nilfs_sufile_get_header_block(sufile, &header_bh);
1203 if (err)
1204 goto failed;
1205
1206 sui = NILFS_SUI(sufile);
1207 kaddr = kmap_atomic(header_bh->b_page);
1208 header = kaddr + bh_offset(header_bh);
1209 sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs);
1210 kunmap_atomic(kaddr);
1211 brelse(header_bh);
1212
1213 sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1;
1214 sui->allocmin = 0;
1215
1216 unlock_new_inode(sufile);
1217 out:
1218 *inodep = sufile;
1219 return 0;
1220 failed:
1221 iget_failed(sufile);
1222 return err;
1223}
1/*
2 * sufile.c - NILFS segment usage file.
3 *
4 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Koji Sato <koji@osrg.net>.
21 * Revised by Ryusuke Konishi <ryusuke@osrg.net>.
22 */
23
24#include <linux/kernel.h>
25#include <linux/fs.h>
26#include <linux/string.h>
27#include <linux/buffer_head.h>
28#include <linux/errno.h>
29#include <linux/nilfs2_fs.h>
30#include "mdt.h"
31#include "sufile.h"
32
33
34struct nilfs_sufile_info {
35 struct nilfs_mdt_info mi;
36 unsigned long ncleansegs;/* number of clean segments */
37 __u64 allocmin; /* lower limit of allocatable segment range */
38 __u64 allocmax; /* upper limit of allocatable segment range */
39};
40
41static inline struct nilfs_sufile_info *NILFS_SUI(struct inode *sufile)
42{
43 return (struct nilfs_sufile_info *)NILFS_MDT(sufile);
44}
45
46static inline unsigned long
47nilfs_sufile_segment_usages_per_block(const struct inode *sufile)
48{
49 return NILFS_MDT(sufile)->mi_entries_per_block;
50}
51
52static unsigned long
53nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum)
54{
55 __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
56 do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
57 return (unsigned long)t;
58}
59
60static unsigned long
61nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum)
62{
63 __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
64 return do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
65}
66
67static unsigned long
68nilfs_sufile_segment_usages_in_block(const struct inode *sufile, __u64 curr,
69 __u64 max)
70{
71 return min_t(unsigned long,
72 nilfs_sufile_segment_usages_per_block(sufile) -
73 nilfs_sufile_get_offset(sufile, curr),
74 max - curr + 1);
75}
76
77static struct nilfs_segment_usage *
78nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum,
79 struct buffer_head *bh, void *kaddr)
80{
81 return kaddr + bh_offset(bh) +
82 nilfs_sufile_get_offset(sufile, segnum) *
83 NILFS_MDT(sufile)->mi_entry_size;
84}
85
86static inline int nilfs_sufile_get_header_block(struct inode *sufile,
87 struct buffer_head **bhp)
88{
89 return nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);
90}
91
92static inline int
93nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,
94 int create, struct buffer_head **bhp)
95{
96 return nilfs_mdt_get_block(sufile,
97 nilfs_sufile_get_blkoff(sufile, segnum),
98 create, NULL, bhp);
99}
100
101static int nilfs_sufile_delete_segment_usage_block(struct inode *sufile,
102 __u64 segnum)
103{
104 return nilfs_mdt_delete_block(sufile,
105 nilfs_sufile_get_blkoff(sufile, segnum));
106}
107
108static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,
109 u64 ncleanadd, u64 ndirtyadd)
110{
111 struct nilfs_sufile_header *header;
112 void *kaddr;
113
114 kaddr = kmap_atomic(header_bh->b_page);
115 header = kaddr + bh_offset(header_bh);
116 le64_add_cpu(&header->sh_ncleansegs, ncleanadd);
117 le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);
118 kunmap_atomic(kaddr);
119
120 mark_buffer_dirty(header_bh);
121}
122
123/**
124 * nilfs_sufile_get_ncleansegs - return the number of clean segments
125 * @sufile: inode of segment usage file
126 */
127unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile)
128{
129 return NILFS_SUI(sufile)->ncleansegs;
130}
131
132/**
133 * nilfs_sufile_updatev - modify multiple segment usages at a time
134 * @sufile: inode of segment usage file
135 * @segnumv: array of segment numbers
136 * @nsegs: size of @segnumv array
137 * @create: creation flag
138 * @ndone: place to store number of modified segments on @segnumv
139 * @dofunc: primitive operation for the update
140 *
141 * Description: nilfs_sufile_updatev() repeatedly calls @dofunc
142 * against the given array of segments. The @dofunc is called with
143 * buffers of a header block and the sufile block in which the target
144 * segment usage entry is contained. If @ndone is given, the number
145 * of successfully modified segments from the head is stored in the
146 * place @ndone points to.
147 *
148 * Return Value: On success, zero is returned. On error, one of the
149 * following negative error codes is returned.
150 *
151 * %-EIO - I/O error.
152 *
153 * %-ENOMEM - Insufficient amount of memory available.
154 *
155 * %-ENOENT - Given segment usage is in hole block (may be returned if
156 * @create is zero)
157 *
158 * %-EINVAL - Invalid segment usage number
159 */
160int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs,
161 int create, size_t *ndone,
162 void (*dofunc)(struct inode *, __u64,
163 struct buffer_head *,
164 struct buffer_head *))
165{
166 struct buffer_head *header_bh, *bh;
167 unsigned long blkoff, prev_blkoff;
168 __u64 *seg;
169 size_t nerr = 0, n = 0;
170 int ret = 0;
171
172 if (unlikely(nsegs == 0))
173 goto out;
174
175 down_write(&NILFS_MDT(sufile)->mi_sem);
176 for (seg = segnumv; seg < segnumv + nsegs; seg++) {
177 if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) {
178 printk(KERN_WARNING
179 "%s: invalid segment number: %llu\n", __func__,
180 (unsigned long long)*seg);
181 nerr++;
182 }
183 }
184 if (nerr > 0) {
185 ret = -EINVAL;
186 goto out_sem;
187 }
188
189 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
190 if (ret < 0)
191 goto out_sem;
192
193 seg = segnumv;
194 blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
195 ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
196 if (ret < 0)
197 goto out_header;
198
199 for (;;) {
200 dofunc(sufile, *seg, header_bh, bh);
201
202 if (++seg >= segnumv + nsegs)
203 break;
204 prev_blkoff = blkoff;
205 blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
206 if (blkoff == prev_blkoff)
207 continue;
208
209 /* get different block */
210 brelse(bh);
211 ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
212 if (unlikely(ret < 0))
213 goto out_header;
214 }
215 brelse(bh);
216
217 out_header:
218 n = seg - segnumv;
219 brelse(header_bh);
220 out_sem:
221 up_write(&NILFS_MDT(sufile)->mi_sem);
222 out:
223 if (ndone)
224 *ndone = n;
225 return ret;
226}
227
228int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create,
229 void (*dofunc)(struct inode *, __u64,
230 struct buffer_head *,
231 struct buffer_head *))
232{
233 struct buffer_head *header_bh, *bh;
234 int ret;
235
236 if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
237 printk(KERN_WARNING "%s: invalid segment number: %llu\n",
238 __func__, (unsigned long long)segnum);
239 return -EINVAL;
240 }
241 down_write(&NILFS_MDT(sufile)->mi_sem);
242
243 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
244 if (ret < 0)
245 goto out_sem;
246
247 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh);
248 if (!ret) {
249 dofunc(sufile, segnum, header_bh, bh);
250 brelse(bh);
251 }
252 brelse(header_bh);
253
254 out_sem:
255 up_write(&NILFS_MDT(sufile)->mi_sem);
256 return ret;
257}
258
259/**
260 * nilfs_sufile_set_alloc_range - limit range of segment to be allocated
261 * @sufile: inode of segment usage file
262 * @start: minimum segment number of allocatable region (inclusive)
263 * @end: maximum segment number of allocatable region (inclusive)
264 *
265 * Return Value: On success, 0 is returned. On error, one of the
266 * following negative error codes is returned.
267 *
268 * %-ERANGE - invalid segment region
269 */
270int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end)
271{
272 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
273 __u64 nsegs;
274 int ret = -ERANGE;
275
276 down_write(&NILFS_MDT(sufile)->mi_sem);
277 nsegs = nilfs_sufile_get_nsegments(sufile);
278
279 if (start <= end && end < nsegs) {
280 sui->allocmin = start;
281 sui->allocmax = end;
282 ret = 0;
283 }
284 up_write(&NILFS_MDT(sufile)->mi_sem);
285 return ret;
286}
287
288/**
289 * nilfs_sufile_alloc - allocate a segment
290 * @sufile: inode of segment usage file
291 * @segnump: pointer to segment number
292 *
293 * Description: nilfs_sufile_alloc() allocates a clean segment.
294 *
295 * Return Value: On success, 0 is returned and the segment number of the
296 * allocated segment is stored in the place pointed by @segnump. On error, one
297 * of the following negative error codes is returned.
298 *
299 * %-EIO - I/O error.
300 *
301 * %-ENOMEM - Insufficient amount of memory available.
302 *
303 * %-ENOSPC - No clean segment left.
304 */
305int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
306{
307 struct buffer_head *header_bh, *su_bh;
308 struct nilfs_sufile_header *header;
309 struct nilfs_segment_usage *su;
310 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
311 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
312 __u64 segnum, maxsegnum, last_alloc;
313 void *kaddr;
314 unsigned long nsegments, ncleansegs, nsus, cnt;
315 int ret, j;
316
317 down_write(&NILFS_MDT(sufile)->mi_sem);
318
319 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
320 if (ret < 0)
321 goto out_sem;
322 kaddr = kmap_atomic(header_bh->b_page);
323 header = kaddr + bh_offset(header_bh);
324 ncleansegs = le64_to_cpu(header->sh_ncleansegs);
325 last_alloc = le64_to_cpu(header->sh_last_alloc);
326 kunmap_atomic(kaddr);
327
328 nsegments = nilfs_sufile_get_nsegments(sufile);
329 maxsegnum = sui->allocmax;
330 segnum = last_alloc + 1;
331 if (segnum < sui->allocmin || segnum > sui->allocmax)
332 segnum = sui->allocmin;
333
334 for (cnt = 0; cnt < nsegments; cnt += nsus) {
335 if (segnum > maxsegnum) {
336 if (cnt < sui->allocmax - sui->allocmin + 1) {
337 /*
338 * wrap around in the limited region.
339 * if allocation started from
340 * sui->allocmin, this never happens.
341 */
342 segnum = sui->allocmin;
343 maxsegnum = last_alloc;
344 } else if (segnum > sui->allocmin &&
345 sui->allocmax + 1 < nsegments) {
346 segnum = sui->allocmax + 1;
347 maxsegnum = nsegments - 1;
348 } else if (sui->allocmin > 0) {
349 segnum = 0;
350 maxsegnum = sui->allocmin - 1;
351 } else {
352 break; /* never happens */
353 }
354 }
355 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
356 &su_bh);
357 if (ret < 0)
358 goto out_header;
359 kaddr = kmap_atomic(su_bh->b_page);
360 su = nilfs_sufile_block_get_segment_usage(
361 sufile, segnum, su_bh, kaddr);
362
363 nsus = nilfs_sufile_segment_usages_in_block(
364 sufile, segnum, maxsegnum);
365 for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
366 if (!nilfs_segment_usage_clean(su))
367 continue;
368 /* found a clean segment */
369 nilfs_segment_usage_set_dirty(su);
370 kunmap_atomic(kaddr);
371
372 kaddr = kmap_atomic(header_bh->b_page);
373 header = kaddr + bh_offset(header_bh);
374 le64_add_cpu(&header->sh_ncleansegs, -1);
375 le64_add_cpu(&header->sh_ndirtysegs, 1);
376 header->sh_last_alloc = cpu_to_le64(segnum);
377 kunmap_atomic(kaddr);
378
379 sui->ncleansegs--;
380 mark_buffer_dirty(header_bh);
381 mark_buffer_dirty(su_bh);
382 nilfs_mdt_mark_dirty(sufile);
383 brelse(su_bh);
384 *segnump = segnum;
385 goto out_header;
386 }
387
388 kunmap_atomic(kaddr);
389 brelse(su_bh);
390 }
391
392 /* no segments left */
393 ret = -ENOSPC;
394
395 out_header:
396 brelse(header_bh);
397
398 out_sem:
399 up_write(&NILFS_MDT(sufile)->mi_sem);
400 return ret;
401}
402
403void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,
404 struct buffer_head *header_bh,
405 struct buffer_head *su_bh)
406{
407 struct nilfs_segment_usage *su;
408 void *kaddr;
409
410 kaddr = kmap_atomic(su_bh->b_page);
411 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
412 if (unlikely(!nilfs_segment_usage_clean(su))) {
413 printk(KERN_WARNING "%s: segment %llu must be clean\n",
414 __func__, (unsigned long long)segnum);
415 kunmap_atomic(kaddr);
416 return;
417 }
418 nilfs_segment_usage_set_dirty(su);
419 kunmap_atomic(kaddr);
420
421 nilfs_sufile_mod_counter(header_bh, -1, 1);
422 NILFS_SUI(sufile)->ncleansegs--;
423
424 mark_buffer_dirty(su_bh);
425 nilfs_mdt_mark_dirty(sufile);
426}
427
428void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,
429 struct buffer_head *header_bh,
430 struct buffer_head *su_bh)
431{
432 struct nilfs_segment_usage *su;
433 void *kaddr;
434 int clean, dirty;
435
436 kaddr = kmap_atomic(su_bh->b_page);
437 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
438 if (su->su_flags == cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY) &&
439 su->su_nblocks == cpu_to_le32(0)) {
440 kunmap_atomic(kaddr);
441 return;
442 }
443 clean = nilfs_segment_usage_clean(su);
444 dirty = nilfs_segment_usage_dirty(su);
445
446 /* make the segment garbage */
447 su->su_lastmod = cpu_to_le64(0);
448 su->su_nblocks = cpu_to_le32(0);
449 su->su_flags = cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY);
450 kunmap_atomic(kaddr);
451
452 nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);
453 NILFS_SUI(sufile)->ncleansegs -= clean;
454
455 mark_buffer_dirty(su_bh);
456 nilfs_mdt_mark_dirty(sufile);
457}
458
459void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,
460 struct buffer_head *header_bh,
461 struct buffer_head *su_bh)
462{
463 struct nilfs_segment_usage *su;
464 void *kaddr;
465 int sudirty;
466
467 kaddr = kmap_atomic(su_bh->b_page);
468 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
469 if (nilfs_segment_usage_clean(su)) {
470 printk(KERN_WARNING "%s: segment %llu is already clean\n",
471 __func__, (unsigned long long)segnum);
472 kunmap_atomic(kaddr);
473 return;
474 }
475 WARN_ON(nilfs_segment_usage_error(su));
476 WARN_ON(!nilfs_segment_usage_dirty(su));
477
478 sudirty = nilfs_segment_usage_dirty(su);
479 nilfs_segment_usage_set_clean(su);
480 kunmap_atomic(kaddr);
481 mark_buffer_dirty(su_bh);
482
483 nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);
484 NILFS_SUI(sufile)->ncleansegs++;
485
486 nilfs_mdt_mark_dirty(sufile);
487}
488
489/**
490 * nilfs_sufile_mark_dirty - mark the buffer having a segment usage dirty
491 * @sufile: inode of segment usage file
492 * @segnum: segment number
493 */
494int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)
495{
496 struct buffer_head *bh;
497 int ret;
498
499 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
500 if (!ret) {
501 mark_buffer_dirty(bh);
502 nilfs_mdt_mark_dirty(sufile);
503 brelse(bh);
504 }
505 return ret;
506}
507
508/**
509 * nilfs_sufile_set_segment_usage - set usage of a segment
510 * @sufile: inode of segment usage file
511 * @segnum: segment number
512 * @nblocks: number of live blocks in the segment
513 * @modtime: modification time (option)
514 */
515int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
516 unsigned long nblocks, time_t modtime)
517{
518 struct buffer_head *bh;
519 struct nilfs_segment_usage *su;
520 void *kaddr;
521 int ret;
522
523 down_write(&NILFS_MDT(sufile)->mi_sem);
524 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
525 if (ret < 0)
526 goto out_sem;
527
528 kaddr = kmap_atomic(bh->b_page);
529 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);
530 WARN_ON(nilfs_segment_usage_error(su));
531 if (modtime)
532 su->su_lastmod = cpu_to_le64(modtime);
533 su->su_nblocks = cpu_to_le32(nblocks);
534 kunmap_atomic(kaddr);
535
536 mark_buffer_dirty(bh);
537 nilfs_mdt_mark_dirty(sufile);
538 brelse(bh);
539
540 out_sem:
541 up_write(&NILFS_MDT(sufile)->mi_sem);
542 return ret;
543}
544
545/**
546 * nilfs_sufile_get_stat - get segment usage statistics
547 * @sufile: inode of segment usage file
548 * @stat: pointer to a structure of segment usage statistics
549 *
550 * Description: nilfs_sufile_get_stat() returns information about segment
551 * usage.
552 *
553 * Return Value: On success, 0 is returned, and segment usage information is
554 * stored in the place pointed by @stat. On error, one of the following
555 * negative error codes is returned.
556 *
557 * %-EIO - I/O error.
558 *
559 * %-ENOMEM - Insufficient amount of memory available.
560 */
561int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat)
562{
563 struct buffer_head *header_bh;
564 struct nilfs_sufile_header *header;
565 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
566 void *kaddr;
567 int ret;
568
569 down_read(&NILFS_MDT(sufile)->mi_sem);
570
571 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
572 if (ret < 0)
573 goto out_sem;
574
575 kaddr = kmap_atomic(header_bh->b_page);
576 header = kaddr + bh_offset(header_bh);
577 sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile);
578 sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs);
579 sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs);
580 sustat->ss_ctime = nilfs->ns_ctime;
581 sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime;
582 spin_lock(&nilfs->ns_last_segment_lock);
583 sustat->ss_prot_seq = nilfs->ns_prot_seq;
584 spin_unlock(&nilfs->ns_last_segment_lock);
585 kunmap_atomic(kaddr);
586 brelse(header_bh);
587
588 out_sem:
589 up_read(&NILFS_MDT(sufile)->mi_sem);
590 return ret;
591}
592
593void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
594 struct buffer_head *header_bh,
595 struct buffer_head *su_bh)
596{
597 struct nilfs_segment_usage *su;
598 void *kaddr;
599 int suclean;
600
601 kaddr = kmap_atomic(su_bh->b_page);
602 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
603 if (nilfs_segment_usage_error(su)) {
604 kunmap_atomic(kaddr);
605 return;
606 }
607 suclean = nilfs_segment_usage_clean(su);
608 nilfs_segment_usage_set_error(su);
609 kunmap_atomic(kaddr);
610
611 if (suclean) {
612 nilfs_sufile_mod_counter(header_bh, -1, 0);
613 NILFS_SUI(sufile)->ncleansegs--;
614 }
615 mark_buffer_dirty(su_bh);
616 nilfs_mdt_mark_dirty(sufile);
617}
618
619/**
620 * nilfs_sufile_truncate_range - truncate range of segment array
621 * @sufile: inode of segment usage file
622 * @start: start segment number (inclusive)
623 * @end: end segment number (inclusive)
624 *
625 * Return Value: On success, 0 is returned. On error, one of the
626 * following negative error codes is returned.
627 *
628 * %-EIO - I/O error.
629 *
630 * %-ENOMEM - Insufficient amount of memory available.
631 *
632 * %-EINVAL - Invalid number of segments specified
633 *
634 * %-EBUSY - Dirty or active segments are present in the range
635 */
636static int nilfs_sufile_truncate_range(struct inode *sufile,
637 __u64 start, __u64 end)
638{
639 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
640 struct buffer_head *header_bh;
641 struct buffer_head *su_bh;
642 struct nilfs_segment_usage *su, *su2;
643 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
644 unsigned long segusages_per_block;
645 unsigned long nsegs, ncleaned;
646 __u64 segnum;
647 void *kaddr;
648 ssize_t n, nc;
649 int ret;
650 int j;
651
652 nsegs = nilfs_sufile_get_nsegments(sufile);
653
654 ret = -EINVAL;
655 if (start > end || start >= nsegs)
656 goto out;
657
658 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
659 if (ret < 0)
660 goto out;
661
662 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
663 ncleaned = 0;
664
665 for (segnum = start; segnum <= end; segnum += n) {
666 n = min_t(unsigned long,
667 segusages_per_block -
668 nilfs_sufile_get_offset(sufile, segnum),
669 end - segnum + 1);
670 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
671 &su_bh);
672 if (ret < 0) {
673 if (ret != -ENOENT)
674 goto out_header;
675 /* hole */
676 continue;
677 }
678 kaddr = kmap_atomic(su_bh->b_page);
679 su = nilfs_sufile_block_get_segment_usage(
680 sufile, segnum, su_bh, kaddr);
681 su2 = su;
682 for (j = 0; j < n; j++, su = (void *)su + susz) {
683 if ((le32_to_cpu(su->su_flags) &
684 ~(1UL << NILFS_SEGMENT_USAGE_ERROR)) ||
685 nilfs_segment_is_active(nilfs, segnum + j)) {
686 ret = -EBUSY;
687 kunmap_atomic(kaddr);
688 brelse(su_bh);
689 goto out_header;
690 }
691 }
692 nc = 0;
693 for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) {
694 if (nilfs_segment_usage_error(su)) {
695 nilfs_segment_usage_set_clean(su);
696 nc++;
697 }
698 }
699 kunmap_atomic(kaddr);
700 if (nc > 0) {
701 mark_buffer_dirty(su_bh);
702 ncleaned += nc;
703 }
704 brelse(su_bh);
705
706 if (n == segusages_per_block) {
707 /* make hole */
708 nilfs_sufile_delete_segment_usage_block(sufile, segnum);
709 }
710 }
711 ret = 0;
712
713out_header:
714 if (ncleaned > 0) {
715 NILFS_SUI(sufile)->ncleansegs += ncleaned;
716 nilfs_sufile_mod_counter(header_bh, ncleaned, 0);
717 nilfs_mdt_mark_dirty(sufile);
718 }
719 brelse(header_bh);
720out:
721 return ret;
722}
723
724/**
725 * nilfs_sufile_resize - resize segment array
726 * @sufile: inode of segment usage file
727 * @newnsegs: new number of segments
728 *
729 * Return Value: On success, 0 is returned. On error, one of the
730 * following negative error codes is returned.
731 *
732 * %-EIO - I/O error.
733 *
734 * %-ENOMEM - Insufficient amount of memory available.
735 *
736 * %-ENOSPC - Enough free space is not left for shrinking
737 *
738 * %-EBUSY - Dirty or active segments exist in the region to be truncated
739 */
740int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs)
741{
742 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
743 struct buffer_head *header_bh;
744 struct nilfs_sufile_header *header;
745 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
746 void *kaddr;
747 unsigned long nsegs, nrsvsegs;
748 int ret = 0;
749
750 down_write(&NILFS_MDT(sufile)->mi_sem);
751
752 nsegs = nilfs_sufile_get_nsegments(sufile);
753 if (nsegs == newnsegs)
754 goto out;
755
756 ret = -ENOSPC;
757 nrsvsegs = nilfs_nrsvsegs(nilfs, newnsegs);
758 if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs)
759 goto out;
760
761 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
762 if (ret < 0)
763 goto out;
764
765 if (newnsegs > nsegs) {
766 sui->ncleansegs += newnsegs - nsegs;
767 } else /* newnsegs < nsegs */ {
768 ret = nilfs_sufile_truncate_range(sufile, newnsegs, nsegs - 1);
769 if (ret < 0)
770 goto out_header;
771
772 sui->ncleansegs -= nsegs - newnsegs;
773 }
774
775 kaddr = kmap_atomic(header_bh->b_page);
776 header = kaddr + bh_offset(header_bh);
777 header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs);
778 kunmap_atomic(kaddr);
779
780 mark_buffer_dirty(header_bh);
781 nilfs_mdt_mark_dirty(sufile);
782 nilfs_set_nsegments(nilfs, newnsegs);
783
784out_header:
785 brelse(header_bh);
786out:
787 up_write(&NILFS_MDT(sufile)->mi_sem);
788 return ret;
789}
790
791/**
792 * nilfs_sufile_get_suinfo -
793 * @sufile: inode of segment usage file
794 * @segnum: segment number to start looking
795 * @buf: array of suinfo
796 * @sisz: byte size of suinfo
797 * @nsi: size of suinfo array
798 *
799 * Description:
800 *
801 * Return Value: On success, 0 is returned and .... On error, one of the
802 * following negative error codes is returned.
803 *
804 * %-EIO - I/O error.
805 *
806 * %-ENOMEM - Insufficient amount of memory available.
807 */
808ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
809 unsigned sisz, size_t nsi)
810{
811 struct buffer_head *su_bh;
812 struct nilfs_segment_usage *su;
813 struct nilfs_suinfo *si = buf;
814 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
815 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
816 void *kaddr;
817 unsigned long nsegs, segusages_per_block;
818 ssize_t n;
819 int ret, i, j;
820
821 down_read(&NILFS_MDT(sufile)->mi_sem);
822
823 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
824 nsegs = min_t(unsigned long,
825 nilfs_sufile_get_nsegments(sufile) - segnum,
826 nsi);
827 for (i = 0; i < nsegs; i += n, segnum += n) {
828 n = min_t(unsigned long,
829 segusages_per_block -
830 nilfs_sufile_get_offset(sufile, segnum),
831 nsegs - i);
832 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
833 &su_bh);
834 if (ret < 0) {
835 if (ret != -ENOENT)
836 goto out;
837 /* hole */
838 memset(si, 0, sisz * n);
839 si = (void *)si + sisz * n;
840 continue;
841 }
842
843 kaddr = kmap_atomic(su_bh->b_page);
844 su = nilfs_sufile_block_get_segment_usage(
845 sufile, segnum, su_bh, kaddr);
846 for (j = 0; j < n;
847 j++, su = (void *)su + susz, si = (void *)si + sisz) {
848 si->sui_lastmod = le64_to_cpu(su->su_lastmod);
849 si->sui_nblocks = le32_to_cpu(su->su_nblocks);
850 si->sui_flags = le32_to_cpu(su->su_flags) &
851 ~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
852 if (nilfs_segment_is_active(nilfs, segnum + j))
853 si->sui_flags |=
854 (1UL << NILFS_SEGMENT_USAGE_ACTIVE);
855 }
856 kunmap_atomic(kaddr);
857 brelse(su_bh);
858 }
859 ret = nsegs;
860
861 out:
862 up_read(&NILFS_MDT(sufile)->mi_sem);
863 return ret;
864}
865
866/**
867 * nilfs_sufile_read - read or get sufile inode
868 * @sb: super block instance
869 * @susize: size of a segment usage entry
870 * @raw_inode: on-disk sufile inode
871 * @inodep: buffer to store the inode
872 */
873int nilfs_sufile_read(struct super_block *sb, size_t susize,
874 struct nilfs_inode *raw_inode, struct inode **inodep)
875{
876 struct inode *sufile;
877 struct nilfs_sufile_info *sui;
878 struct buffer_head *header_bh;
879 struct nilfs_sufile_header *header;
880 void *kaddr;
881 int err;
882
883 sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO);
884 if (unlikely(!sufile))
885 return -ENOMEM;
886 if (!(sufile->i_state & I_NEW))
887 goto out;
888
889 err = nilfs_mdt_init(sufile, NILFS_MDT_GFP, sizeof(*sui));
890 if (err)
891 goto failed;
892
893 nilfs_mdt_set_entry_size(sufile, susize,
894 sizeof(struct nilfs_sufile_header));
895
896 err = nilfs_read_inode_common(sufile, raw_inode);
897 if (err)
898 goto failed;
899
900 err = nilfs_sufile_get_header_block(sufile, &header_bh);
901 if (err)
902 goto failed;
903
904 sui = NILFS_SUI(sufile);
905 kaddr = kmap_atomic(header_bh->b_page);
906 header = kaddr + bh_offset(header_bh);
907 sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs);
908 kunmap_atomic(kaddr);
909 brelse(header_bh);
910
911 sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1;
912 sui->allocmin = 0;
913
914 unlock_new_inode(sufile);
915 out:
916 *inodep = sufile;
917 return 0;
918 failed:
919 iget_failed(sufile);
920 return err;
921}