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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 t = div64_ul(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
73/**
74 * nilfs_sufile_segment_usage_offset - calculate the byte offset of a segment
75 * usage entry in the folio containing it
76 * @sufile: segment usage file inode
77 * @segnum: number of segment usage
78 * @bh: buffer head of block containing segment usage indexed by @segnum
79 *
80 * Return: Byte offset in the folio of the segment usage entry.
81 */
82static size_t nilfs_sufile_segment_usage_offset(const struct inode *sufile,
83 __u64 segnum,
84 struct buffer_head *bh)
85{
86 return offset_in_folio(bh->b_folio, bh->b_data) +
87 nilfs_sufile_get_offset(sufile, segnum) *
88 NILFS_MDT(sufile)->mi_entry_size;
89}
90
91static int nilfs_sufile_get_header_block(struct inode *sufile,
92 struct buffer_head **bhp)
93{
94 int err = nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);
95
96 if (unlikely(err == -ENOENT)) {
97 nilfs_error(sufile->i_sb,
98 "missing header block in segment usage metadata");
99 err = -EIO;
100 }
101 return err;
102}
103
104static inline int
105nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,
106 int create, struct buffer_head **bhp)
107{
108 return nilfs_mdt_get_block(sufile,
109 nilfs_sufile_get_blkoff(sufile, segnum),
110 create, NULL, bhp);
111}
112
113static int nilfs_sufile_delete_segment_usage_block(struct inode *sufile,
114 __u64 segnum)
115{
116 return nilfs_mdt_delete_block(sufile,
117 nilfs_sufile_get_blkoff(sufile, segnum));
118}
119
120static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,
121 u64 ncleanadd, u64 ndirtyadd)
122{
123 struct nilfs_sufile_header *header;
124
125 header = kmap_local_folio(header_bh->b_folio, 0);
126 le64_add_cpu(&header->sh_ncleansegs, ncleanadd);
127 le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);
128 kunmap_local(header);
129
130 mark_buffer_dirty(header_bh);
131}
132
133/**
134 * nilfs_sufile_get_ncleansegs - return the number of clean segments
135 * @sufile: inode of segment usage file
136 */
137unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile)
138{
139 return NILFS_SUI(sufile)->ncleansegs;
140}
141
142/**
143 * nilfs_sufile_updatev - modify multiple segment usages at a time
144 * @sufile: inode of segment usage file
145 * @segnumv: array of segment numbers
146 * @nsegs: size of @segnumv array
147 * @create: creation flag
148 * @ndone: place to store number of modified segments on @segnumv
149 * @dofunc: primitive operation for the update
150 *
151 * Description: nilfs_sufile_updatev() repeatedly calls @dofunc
152 * against the given array of segments. The @dofunc is called with
153 * buffers of a header block and the sufile block in which the target
154 * segment usage entry is contained. If @ndone is given, the number
155 * of successfully modified segments from the head is stored in the
156 * place @ndone points to.
157 *
158 * Return Value: On success, zero is returned. On error, one of the
159 * following negative error codes is returned.
160 *
161 * %-EIO - I/O error.
162 *
163 * %-ENOMEM - Insufficient amount of memory available.
164 *
165 * %-ENOENT - Given segment usage is in hole block (may be returned if
166 * @create is zero)
167 *
168 * %-EINVAL - Invalid segment usage number
169 */
170int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs,
171 int create, size_t *ndone,
172 void (*dofunc)(struct inode *, __u64,
173 struct buffer_head *,
174 struct buffer_head *))
175{
176 struct buffer_head *header_bh, *bh;
177 unsigned long blkoff, prev_blkoff;
178 __u64 *seg;
179 size_t nerr = 0, n = 0;
180 int ret = 0;
181
182 if (unlikely(nsegs == 0))
183 goto out;
184
185 down_write(&NILFS_MDT(sufile)->mi_sem);
186 for (seg = segnumv; seg < segnumv + nsegs; seg++) {
187 if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) {
188 nilfs_warn(sufile->i_sb,
189 "%s: invalid segment number: %llu",
190 __func__, (unsigned long long)*seg);
191 nerr++;
192 }
193 }
194 if (nerr > 0) {
195 ret = -EINVAL;
196 goto out_sem;
197 }
198
199 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
200 if (ret < 0)
201 goto out_sem;
202
203 seg = segnumv;
204 blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
205 ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
206 if (ret < 0)
207 goto out_header;
208
209 for (;;) {
210 dofunc(sufile, *seg, header_bh, bh);
211
212 if (++seg >= segnumv + nsegs)
213 break;
214 prev_blkoff = blkoff;
215 blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
216 if (blkoff == prev_blkoff)
217 continue;
218
219 /* get different block */
220 brelse(bh);
221 ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
222 if (unlikely(ret < 0))
223 goto out_header;
224 }
225 brelse(bh);
226
227 out_header:
228 n = seg - segnumv;
229 brelse(header_bh);
230 out_sem:
231 up_write(&NILFS_MDT(sufile)->mi_sem);
232 out:
233 if (ndone)
234 *ndone = n;
235 return ret;
236}
237
238int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create,
239 void (*dofunc)(struct inode *, __u64,
240 struct buffer_head *,
241 struct buffer_head *))
242{
243 struct buffer_head *header_bh, *bh;
244 int ret;
245
246 if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
247 nilfs_warn(sufile->i_sb, "%s: invalid segment number: %llu",
248 __func__, (unsigned long long)segnum);
249 return -EINVAL;
250 }
251 down_write(&NILFS_MDT(sufile)->mi_sem);
252
253 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
254 if (ret < 0)
255 goto out_sem;
256
257 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh);
258 if (!ret) {
259 dofunc(sufile, segnum, header_bh, bh);
260 brelse(bh);
261 }
262 brelse(header_bh);
263
264 out_sem:
265 up_write(&NILFS_MDT(sufile)->mi_sem);
266 return ret;
267}
268
269/**
270 * nilfs_sufile_set_alloc_range - limit range of segment to be allocated
271 * @sufile: inode of segment usage file
272 * @start: minimum segment number of allocatable region (inclusive)
273 * @end: maximum segment number of allocatable region (inclusive)
274 *
275 * Return Value: On success, 0 is returned. On error, one of the
276 * following negative error codes is returned.
277 *
278 * %-ERANGE - invalid segment region
279 */
280int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end)
281{
282 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
283 __u64 nsegs;
284 int ret = -ERANGE;
285
286 down_write(&NILFS_MDT(sufile)->mi_sem);
287 nsegs = nilfs_sufile_get_nsegments(sufile);
288
289 if (start <= end && end < nsegs) {
290 sui->allocmin = start;
291 sui->allocmax = end;
292 ret = 0;
293 }
294 up_write(&NILFS_MDT(sufile)->mi_sem);
295 return ret;
296}
297
298/**
299 * nilfs_sufile_alloc - allocate a segment
300 * @sufile: inode of segment usage file
301 * @segnump: pointer to segment number
302 *
303 * Description: nilfs_sufile_alloc() allocates a clean segment.
304 *
305 * Return Value: On success, 0 is returned and the segment number of the
306 * allocated segment is stored in the place pointed by @segnump. On error, one
307 * of the following negative error codes is returned.
308 *
309 * %-EIO - I/O error.
310 *
311 * %-ENOMEM - Insufficient amount of memory available.
312 *
313 * %-ENOSPC - No clean segment left.
314 */
315int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
316{
317 struct buffer_head *header_bh, *su_bh;
318 struct nilfs_sufile_header *header;
319 struct nilfs_segment_usage *su;
320 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
321 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
322 __u64 segnum, maxsegnum, last_alloc;
323 size_t offset;
324 void *kaddr;
325 unsigned long nsegments, nsus, cnt;
326 int ret, j;
327
328 down_write(&NILFS_MDT(sufile)->mi_sem);
329
330 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
331 if (ret < 0)
332 goto out_sem;
333 header = kmap_local_folio(header_bh->b_folio, 0);
334 last_alloc = le64_to_cpu(header->sh_last_alloc);
335 kunmap_local(header);
336
337 nsegments = nilfs_sufile_get_nsegments(sufile);
338 maxsegnum = sui->allocmax;
339 segnum = last_alloc + 1;
340 if (segnum < sui->allocmin || segnum > sui->allocmax)
341 segnum = sui->allocmin;
342
343 for (cnt = 0; cnt < nsegments; cnt += nsus) {
344 if (segnum > maxsegnum) {
345 if (cnt < sui->allocmax - sui->allocmin + 1) {
346 /*
347 * wrap around in the limited region.
348 * if allocation started from
349 * sui->allocmin, this never happens.
350 */
351 segnum = sui->allocmin;
352 maxsegnum = last_alloc;
353 } else if (segnum > sui->allocmin &&
354 sui->allocmax + 1 < nsegments) {
355 segnum = sui->allocmax + 1;
356 maxsegnum = nsegments - 1;
357 } else if (sui->allocmin > 0) {
358 segnum = 0;
359 maxsegnum = sui->allocmin - 1;
360 } else {
361 break; /* never happens */
362 }
363 }
364 trace_nilfs2_segment_usage_check(sufile, segnum, cnt);
365 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
366 &su_bh);
367 if (ret < 0)
368 goto out_header;
369
370 offset = nilfs_sufile_segment_usage_offset(sufile, segnum,
371 su_bh);
372 su = kaddr = kmap_local_folio(su_bh->b_folio, offset);
373
374 nsus = nilfs_sufile_segment_usages_in_block(
375 sufile, segnum, maxsegnum);
376 for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
377 if (!nilfs_segment_usage_clean(su))
378 continue;
379 /* found a clean segment */
380 nilfs_segment_usage_set_dirty(su);
381 kunmap_local(kaddr);
382
383 header = kmap_local_folio(header_bh->b_folio, 0);
384 le64_add_cpu(&header->sh_ncleansegs, -1);
385 le64_add_cpu(&header->sh_ndirtysegs, 1);
386 header->sh_last_alloc = cpu_to_le64(segnum);
387 kunmap_local(header);
388
389 sui->ncleansegs--;
390 mark_buffer_dirty(header_bh);
391 mark_buffer_dirty(su_bh);
392 nilfs_mdt_mark_dirty(sufile);
393 brelse(su_bh);
394 *segnump = segnum;
395
396 trace_nilfs2_segment_usage_allocated(sufile, segnum);
397
398 goto out_header;
399 }
400
401 kunmap_local(kaddr);
402 brelse(su_bh);
403 }
404
405 /* no segments left */
406 ret = -ENOSPC;
407
408 out_header:
409 brelse(header_bh);
410
411 out_sem:
412 up_write(&NILFS_MDT(sufile)->mi_sem);
413 return ret;
414}
415
416void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,
417 struct buffer_head *header_bh,
418 struct buffer_head *su_bh)
419{
420 struct nilfs_segment_usage *su;
421 size_t offset;
422
423 offset = nilfs_sufile_segment_usage_offset(sufile, segnum, su_bh);
424 su = kmap_local_folio(su_bh->b_folio, offset);
425 if (unlikely(!nilfs_segment_usage_clean(su))) {
426 nilfs_warn(sufile->i_sb, "%s: segment %llu must be clean",
427 __func__, (unsigned long long)segnum);
428 kunmap_local(su);
429 return;
430 }
431 nilfs_segment_usage_set_dirty(su);
432 kunmap_local(su);
433
434 nilfs_sufile_mod_counter(header_bh, -1, 1);
435 NILFS_SUI(sufile)->ncleansegs--;
436
437 mark_buffer_dirty(su_bh);
438 nilfs_mdt_mark_dirty(sufile);
439}
440
441void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,
442 struct buffer_head *header_bh,
443 struct buffer_head *su_bh)
444{
445 struct nilfs_segment_usage *su;
446 size_t offset;
447 int clean, dirty;
448
449 offset = nilfs_sufile_segment_usage_offset(sufile, segnum, su_bh);
450 su = kmap_local_folio(su_bh->b_folio, offset);
451 if (su->su_flags == cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY)) &&
452 su->su_nblocks == cpu_to_le32(0)) {
453 kunmap_local(su);
454 return;
455 }
456 clean = nilfs_segment_usage_clean(su);
457 dirty = nilfs_segment_usage_dirty(su);
458
459 /* make the segment garbage */
460 su->su_lastmod = cpu_to_le64(0);
461 su->su_nblocks = cpu_to_le32(0);
462 su->su_flags = cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY));
463 kunmap_local(su);
464
465 nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);
466 NILFS_SUI(sufile)->ncleansegs -= clean;
467
468 mark_buffer_dirty(su_bh);
469 nilfs_mdt_mark_dirty(sufile);
470}
471
472void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,
473 struct buffer_head *header_bh,
474 struct buffer_head *su_bh)
475{
476 struct nilfs_segment_usage *su;
477 size_t offset;
478 int sudirty;
479
480 offset = nilfs_sufile_segment_usage_offset(sufile, segnum, su_bh);
481 su = kmap_local_folio(su_bh->b_folio, offset);
482 if (nilfs_segment_usage_clean(su)) {
483 nilfs_warn(sufile->i_sb, "%s: segment %llu is already clean",
484 __func__, (unsigned long long)segnum);
485 kunmap_local(su);
486 return;
487 }
488 if (unlikely(nilfs_segment_usage_error(su)))
489 nilfs_warn(sufile->i_sb, "free segment %llu marked in error",
490 (unsigned long long)segnum);
491
492 sudirty = nilfs_segment_usage_dirty(su);
493 if (unlikely(!sudirty))
494 nilfs_warn(sufile->i_sb, "free unallocated segment %llu",
495 (unsigned long long)segnum);
496
497 nilfs_segment_usage_set_clean(su);
498 kunmap_local(su);
499 mark_buffer_dirty(su_bh);
500
501 nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);
502 NILFS_SUI(sufile)->ncleansegs++;
503
504 nilfs_mdt_mark_dirty(sufile);
505
506 trace_nilfs2_segment_usage_freed(sufile, segnum);
507}
508
509/**
510 * nilfs_sufile_mark_dirty - mark the buffer having a segment usage dirty
511 * @sufile: inode of segment usage file
512 * @segnum: segment number
513 */
514int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)
515{
516 struct buffer_head *bh;
517 size_t offset;
518 struct nilfs_segment_usage *su;
519 int ret;
520
521 down_write(&NILFS_MDT(sufile)->mi_sem);
522 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
523 if (unlikely(ret)) {
524 if (ret == -ENOENT) {
525 nilfs_error(sufile->i_sb,
526 "segment usage for segment %llu is unreadable due to a hole block",
527 (unsigned long long)segnum);
528 ret = -EIO;
529 }
530 goto out_sem;
531 }
532
533 offset = nilfs_sufile_segment_usage_offset(sufile, segnum, bh);
534 su = kmap_local_folio(bh->b_folio, offset);
535 if (unlikely(nilfs_segment_usage_error(su))) {
536 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
537
538 kunmap_local(su);
539 brelse(bh);
540 if (nilfs_segment_is_active(nilfs, segnum)) {
541 nilfs_error(sufile->i_sb,
542 "active segment %llu is erroneous",
543 (unsigned long long)segnum);
544 } else {
545 /*
546 * Segments marked erroneous are never allocated by
547 * nilfs_sufile_alloc(); only active segments, ie,
548 * the segments indexed by ns_segnum or ns_nextnum,
549 * can be erroneous here.
550 */
551 WARN_ON_ONCE(1);
552 }
553 ret = -EIO;
554 } else {
555 nilfs_segment_usage_set_dirty(su);
556 kunmap_local(su);
557 mark_buffer_dirty(bh);
558 nilfs_mdt_mark_dirty(sufile);
559 brelse(bh);
560 }
561out_sem:
562 up_write(&NILFS_MDT(sufile)->mi_sem);
563 return ret;
564}
565
566/**
567 * nilfs_sufile_set_segment_usage - set usage of a segment
568 * @sufile: inode of segment usage file
569 * @segnum: segment number
570 * @nblocks: number of live blocks in the segment
571 * @modtime: modification time (option)
572 */
573int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
574 unsigned long nblocks, time64_t modtime)
575{
576 struct buffer_head *bh;
577 struct nilfs_segment_usage *su;
578 size_t offset;
579 int ret;
580
581 down_write(&NILFS_MDT(sufile)->mi_sem);
582 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
583 if (ret < 0)
584 goto out_sem;
585
586 offset = nilfs_sufile_segment_usage_offset(sufile, segnum, bh);
587 su = kmap_local_folio(bh->b_folio, offset);
588 if (modtime) {
589 /*
590 * Check segusage error and set su_lastmod only when updating
591 * this entry with a valid timestamp, not for cancellation.
592 */
593 WARN_ON_ONCE(nilfs_segment_usage_error(su));
594 su->su_lastmod = cpu_to_le64(modtime);
595 }
596 su->su_nblocks = cpu_to_le32(nblocks);
597 kunmap_local(su);
598
599 mark_buffer_dirty(bh);
600 nilfs_mdt_mark_dirty(sufile);
601 brelse(bh);
602
603 out_sem:
604 up_write(&NILFS_MDT(sufile)->mi_sem);
605 return ret;
606}
607
608/**
609 * nilfs_sufile_get_stat - get segment usage statistics
610 * @sufile: inode of segment usage file
611 * @sustat: pointer to a structure of segment usage statistics
612 *
613 * Description: nilfs_sufile_get_stat() returns information about segment
614 * usage.
615 *
616 * Return Value: On success, 0 is returned, and segment usage information is
617 * stored in the place pointed by @sustat. On error, one of the following
618 * negative error codes is returned.
619 *
620 * %-EIO - I/O error.
621 *
622 * %-ENOMEM - Insufficient amount of memory available.
623 */
624int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat)
625{
626 struct buffer_head *header_bh;
627 struct nilfs_sufile_header *header;
628 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
629 int ret;
630
631 down_read(&NILFS_MDT(sufile)->mi_sem);
632
633 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
634 if (ret < 0)
635 goto out_sem;
636
637 header = kmap_local_folio(header_bh->b_folio, 0);
638 sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile);
639 sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs);
640 sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs);
641 sustat->ss_ctime = nilfs->ns_ctime;
642 sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime;
643 spin_lock(&nilfs->ns_last_segment_lock);
644 sustat->ss_prot_seq = nilfs->ns_prot_seq;
645 spin_unlock(&nilfs->ns_last_segment_lock);
646 kunmap_local(header);
647 brelse(header_bh);
648
649 out_sem:
650 up_read(&NILFS_MDT(sufile)->mi_sem);
651 return ret;
652}
653
654void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
655 struct buffer_head *header_bh,
656 struct buffer_head *su_bh)
657{
658 struct nilfs_segment_usage *su;
659 size_t offset;
660 int suclean;
661
662 offset = nilfs_sufile_segment_usage_offset(sufile, segnum, su_bh);
663 su = kmap_local_folio(su_bh->b_folio, offset);
664 if (nilfs_segment_usage_error(su)) {
665 kunmap_local(su);
666 return;
667 }
668 suclean = nilfs_segment_usage_clean(su);
669 nilfs_segment_usage_set_error(su);
670 kunmap_local(su);
671
672 if (suclean) {
673 nilfs_sufile_mod_counter(header_bh, -1, 0);
674 NILFS_SUI(sufile)->ncleansegs--;
675 }
676 mark_buffer_dirty(su_bh);
677 nilfs_mdt_mark_dirty(sufile);
678}
679
680/**
681 * nilfs_sufile_truncate_range - truncate range of segment array
682 * @sufile: inode of segment usage file
683 * @start: start segment number (inclusive)
684 * @end: end segment number (inclusive)
685 *
686 * Return Value: On success, 0 is returned. On error, one of the
687 * following negative error codes is returned.
688 *
689 * %-EIO - I/O error.
690 *
691 * %-ENOMEM - Insufficient amount of memory available.
692 *
693 * %-EINVAL - Invalid number of segments specified
694 *
695 * %-EBUSY - Dirty or active segments are present in the range
696 */
697static int nilfs_sufile_truncate_range(struct inode *sufile,
698 __u64 start, __u64 end)
699{
700 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
701 struct buffer_head *header_bh;
702 struct buffer_head *su_bh;
703 struct nilfs_segment_usage *su, *su2;
704 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
705 unsigned long segusages_per_block;
706 unsigned long nsegs, ncleaned;
707 __u64 segnum;
708 size_t offset;
709 ssize_t n, nc;
710 int ret;
711 int j;
712
713 nsegs = nilfs_sufile_get_nsegments(sufile);
714
715 ret = -EINVAL;
716 if (start > end || start >= nsegs)
717 goto out;
718
719 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
720 if (ret < 0)
721 goto out;
722
723 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
724 ncleaned = 0;
725
726 for (segnum = start; segnum <= end; segnum += n) {
727 n = min_t(unsigned long,
728 segusages_per_block -
729 nilfs_sufile_get_offset(sufile, segnum),
730 end - segnum + 1);
731 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
732 &su_bh);
733 if (ret < 0) {
734 if (ret != -ENOENT)
735 goto out_header;
736 /* hole */
737 continue;
738 }
739 offset = nilfs_sufile_segment_usage_offset(sufile, segnum,
740 su_bh);
741 su = kmap_local_folio(su_bh->b_folio, offset);
742 su2 = su;
743 for (j = 0; j < n; j++, su = (void *)su + susz) {
744 if ((le32_to_cpu(su->su_flags) &
745 ~BIT(NILFS_SEGMENT_USAGE_ERROR)) ||
746 nilfs_segment_is_active(nilfs, segnum + j)) {
747 ret = -EBUSY;
748 kunmap_local(su2);
749 brelse(su_bh);
750 goto out_header;
751 }
752 }
753 nc = 0;
754 for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) {
755 if (nilfs_segment_usage_error(su)) {
756 nilfs_segment_usage_set_clean(su);
757 nc++;
758 }
759 }
760 kunmap_local(su2);
761 if (nc > 0) {
762 mark_buffer_dirty(su_bh);
763 ncleaned += nc;
764 }
765 brelse(su_bh);
766
767 if (n == segusages_per_block) {
768 /* make hole */
769 nilfs_sufile_delete_segment_usage_block(sufile, segnum);
770 }
771 }
772 ret = 0;
773
774out_header:
775 if (ncleaned > 0) {
776 NILFS_SUI(sufile)->ncleansegs += ncleaned;
777 nilfs_sufile_mod_counter(header_bh, ncleaned, 0);
778 nilfs_mdt_mark_dirty(sufile);
779 }
780 brelse(header_bh);
781out:
782 return ret;
783}
784
785/**
786 * nilfs_sufile_resize - resize segment array
787 * @sufile: inode of segment usage file
788 * @newnsegs: new number of segments
789 *
790 * Return Value: On success, 0 is returned. On error, one of the
791 * following negative error codes is returned.
792 *
793 * %-EIO - I/O error.
794 *
795 * %-ENOMEM - Insufficient amount of memory available.
796 *
797 * %-ENOSPC - Enough free space is not left for shrinking
798 *
799 * %-EBUSY - Dirty or active segments exist in the region to be truncated
800 */
801int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs)
802{
803 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
804 struct buffer_head *header_bh;
805 struct nilfs_sufile_header *header;
806 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
807 unsigned long nsegs, nrsvsegs;
808 int ret = 0;
809
810 down_write(&NILFS_MDT(sufile)->mi_sem);
811
812 nsegs = nilfs_sufile_get_nsegments(sufile);
813 if (nsegs == newnsegs)
814 goto out;
815
816 ret = -ENOSPC;
817 nrsvsegs = nilfs_nrsvsegs(nilfs, newnsegs);
818 if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs)
819 goto out;
820
821 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
822 if (ret < 0)
823 goto out;
824
825 if (newnsegs > nsegs) {
826 sui->ncleansegs += newnsegs - nsegs;
827 } else /* newnsegs < nsegs */ {
828 ret = nilfs_sufile_truncate_range(sufile, newnsegs, nsegs - 1);
829 if (ret < 0)
830 goto out_header;
831
832 sui->ncleansegs -= nsegs - newnsegs;
833
834 /*
835 * If the sufile is successfully truncated, immediately adjust
836 * the segment allocation space while locking the semaphore
837 * "mi_sem" so that nilfs_sufile_alloc() never allocates
838 * segments in the truncated space.
839 */
840 sui->allocmax = newnsegs - 1;
841 sui->allocmin = 0;
842 }
843
844 header = kmap_local_folio(header_bh->b_folio, 0);
845 header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs);
846 kunmap_local(header);
847
848 mark_buffer_dirty(header_bh);
849 nilfs_mdt_mark_dirty(sufile);
850 nilfs_set_nsegments(nilfs, newnsegs);
851
852out_header:
853 brelse(header_bh);
854out:
855 up_write(&NILFS_MDT(sufile)->mi_sem);
856 return ret;
857}
858
859/**
860 * nilfs_sufile_get_suinfo - get segment usage information
861 * @sufile: inode of segment usage file
862 * @segnum: segment number to start looking
863 * @buf: array of suinfo
864 * @sisz: byte size of suinfo
865 * @nsi: size of suinfo array
866 *
867 * Return: Count of segment usage info items stored in the output buffer on
868 * success, or the following negative error code on failure.
869 * * %-EIO - I/O error (including metadata corruption).
870 * * %-ENOMEM - Insufficient memory available.
871 */
872ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
873 unsigned int sisz, size_t nsi)
874{
875 struct buffer_head *su_bh;
876 struct nilfs_segment_usage *su;
877 struct nilfs_suinfo *si = buf;
878 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
879 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
880 size_t offset;
881 void *kaddr;
882 unsigned long nsegs, segusages_per_block;
883 ssize_t n;
884 int ret, i, j;
885
886 down_read(&NILFS_MDT(sufile)->mi_sem);
887
888 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
889 nsegs = min_t(unsigned long,
890 nilfs_sufile_get_nsegments(sufile) - segnum,
891 nsi);
892 for (i = 0; i < nsegs; i += n, segnum += n) {
893 n = min_t(unsigned long,
894 segusages_per_block -
895 nilfs_sufile_get_offset(sufile, segnum),
896 nsegs - i);
897 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
898 &su_bh);
899 if (ret < 0) {
900 if (ret != -ENOENT)
901 goto out;
902 /* hole */
903 memset(si, 0, sisz * n);
904 si = (void *)si + sisz * n;
905 continue;
906 }
907
908 offset = nilfs_sufile_segment_usage_offset(sufile, segnum,
909 su_bh);
910 su = kaddr = kmap_local_folio(su_bh->b_folio, offset);
911 for (j = 0; j < n;
912 j++, su = (void *)su + susz, si = (void *)si + sisz) {
913 si->sui_lastmod = le64_to_cpu(su->su_lastmod);
914 si->sui_nblocks = le32_to_cpu(su->su_nblocks);
915 si->sui_flags = le32_to_cpu(su->su_flags) &
916 ~BIT(NILFS_SEGMENT_USAGE_ACTIVE);
917 if (nilfs_segment_is_active(nilfs, segnum + j))
918 si->sui_flags |=
919 BIT(NILFS_SEGMENT_USAGE_ACTIVE);
920 }
921 kunmap_local(kaddr);
922 brelse(su_bh);
923 }
924 ret = nsegs;
925
926 out:
927 up_read(&NILFS_MDT(sufile)->mi_sem);
928 return ret;
929}
930
931/**
932 * nilfs_sufile_set_suinfo - sets segment usage info
933 * @sufile: inode of segment usage file
934 * @buf: array of suinfo_update
935 * @supsz: byte size of suinfo_update
936 * @nsup: size of suinfo_update array
937 *
938 * Description: Takes an array of nilfs_suinfo_update structs and updates
939 * segment usage accordingly. Only the fields indicated by the sup_flags
940 * are updated.
941 *
942 * Return Value: On success, 0 is returned. On error, one of the
943 * following negative error codes is returned.
944 *
945 * %-EIO - I/O error.
946 *
947 * %-ENOMEM - Insufficient amount of memory available.
948 *
949 * %-EINVAL - Invalid values in input (segment number, flags or nblocks)
950 */
951ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf,
952 unsigned int supsz, size_t nsup)
953{
954 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
955 struct buffer_head *header_bh, *bh;
956 struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup;
957 struct nilfs_segment_usage *su;
958 size_t offset;
959 unsigned long blkoff, prev_blkoff;
960 int cleansi, cleansu, dirtysi, dirtysu;
961 long ncleaned = 0, ndirtied = 0;
962 int ret = 0;
963
964 if (unlikely(nsup == 0))
965 return ret;
966
967 for (sup = buf; sup < supend; sup = (void *)sup + supsz) {
968 if (sup->sup_segnum >= nilfs->ns_nsegments
969 || (sup->sup_flags &
970 (~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS))
971 || (nilfs_suinfo_update_nblocks(sup) &&
972 sup->sup_sui.sui_nblocks >
973 nilfs->ns_blocks_per_segment))
974 return -EINVAL;
975 }
976
977 down_write(&NILFS_MDT(sufile)->mi_sem);
978
979 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
980 if (ret < 0)
981 goto out_sem;
982
983 sup = buf;
984 blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
985 ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
986 if (ret < 0)
987 goto out_header;
988
989 for (;;) {
990 offset = nilfs_sufile_segment_usage_offset(
991 sufile, sup->sup_segnum, bh);
992 su = kmap_local_folio(bh->b_folio, offset);
993
994 if (nilfs_suinfo_update_lastmod(sup))
995 su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod);
996
997 if (nilfs_suinfo_update_nblocks(sup))
998 su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks);
999
1000 if (nilfs_suinfo_update_flags(sup)) {
1001 /*
1002 * Active flag is a virtual flag projected by running
1003 * nilfs kernel code - drop it not to write it to
1004 * disk.
1005 */
1006 sup->sup_sui.sui_flags &=
1007 ~BIT(NILFS_SEGMENT_USAGE_ACTIVE);
1008
1009 cleansi = nilfs_suinfo_clean(&sup->sup_sui);
1010 cleansu = nilfs_segment_usage_clean(su);
1011 dirtysi = nilfs_suinfo_dirty(&sup->sup_sui);
1012 dirtysu = nilfs_segment_usage_dirty(su);
1013
1014 if (cleansi && !cleansu)
1015 ++ncleaned;
1016 else if (!cleansi && cleansu)
1017 --ncleaned;
1018
1019 if (dirtysi && !dirtysu)
1020 ++ndirtied;
1021 else if (!dirtysi && dirtysu)
1022 --ndirtied;
1023
1024 su->su_flags = cpu_to_le32(sup->sup_sui.sui_flags);
1025 }
1026
1027 kunmap_local(su);
1028
1029 sup = (void *)sup + supsz;
1030 if (sup >= supend)
1031 break;
1032
1033 prev_blkoff = blkoff;
1034 blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
1035 if (blkoff == prev_blkoff)
1036 continue;
1037
1038 /* get different block */
1039 mark_buffer_dirty(bh);
1040 put_bh(bh);
1041 ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
1042 if (unlikely(ret < 0))
1043 goto out_mark;
1044 }
1045 mark_buffer_dirty(bh);
1046 put_bh(bh);
1047
1048 out_mark:
1049 if (ncleaned || ndirtied) {
1050 nilfs_sufile_mod_counter(header_bh, (u64)ncleaned,
1051 (u64)ndirtied);
1052 NILFS_SUI(sufile)->ncleansegs += ncleaned;
1053 }
1054 nilfs_mdt_mark_dirty(sufile);
1055 out_header:
1056 put_bh(header_bh);
1057 out_sem:
1058 up_write(&NILFS_MDT(sufile)->mi_sem);
1059 return ret;
1060}
1061
1062/**
1063 * nilfs_sufile_trim_fs() - trim ioctl handle function
1064 * @sufile: inode of segment usage file
1065 * @range: fstrim_range structure
1066 *
1067 * start: First Byte to trim
1068 * len: number of Bytes to trim from start
1069 * minlen: minimum extent length in Bytes
1070 *
1071 * Decription: nilfs_sufile_trim_fs goes through all segments containing bytes
1072 * from start to start+len. start is rounded up to the next block boundary
1073 * and start+len is rounded down. For each clean segment blkdev_issue_discard
1074 * function is invoked.
1075 *
1076 * Return Value: On success, 0 is returned or negative error code, otherwise.
1077 */
1078int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)
1079{
1080 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
1081 struct buffer_head *su_bh;
1082 struct nilfs_segment_usage *su;
1083 size_t offset;
1084 void *kaddr;
1085 size_t n, i, susz = NILFS_MDT(sufile)->mi_entry_size;
1086 sector_t seg_start, seg_end, start_block, end_block;
1087 sector_t start = 0, nblocks = 0;
1088 u64 segnum, segnum_end, minlen, len, max_blocks, ndiscarded = 0;
1089 int ret = 0;
1090 unsigned int sects_per_block;
1091
1092 sects_per_block = (1 << nilfs->ns_blocksize_bits) /
1093 bdev_logical_block_size(nilfs->ns_bdev);
1094 len = range->len >> nilfs->ns_blocksize_bits;
1095 minlen = range->minlen >> nilfs->ns_blocksize_bits;
1096 max_blocks = ((u64)nilfs->ns_nsegments * nilfs->ns_blocks_per_segment);
1097
1098 if (!len || range->start >= max_blocks << nilfs->ns_blocksize_bits)
1099 return -EINVAL;
1100
1101 start_block = (range->start + nilfs->ns_blocksize - 1) >>
1102 nilfs->ns_blocksize_bits;
1103
1104 /*
1105 * range->len can be very large (actually, it is set to
1106 * ULLONG_MAX by default) - truncate upper end of the range
1107 * carefully so as not to overflow.
1108 */
1109 if (max_blocks - start_block < len)
1110 end_block = max_blocks - 1;
1111 else
1112 end_block = start_block + len - 1;
1113
1114 segnum = nilfs_get_segnum_of_block(nilfs, start_block);
1115 segnum_end = nilfs_get_segnum_of_block(nilfs, end_block);
1116
1117 down_read(&NILFS_MDT(sufile)->mi_sem);
1118
1119 while (segnum <= segnum_end) {
1120 n = nilfs_sufile_segment_usages_in_block(sufile, segnum,
1121 segnum_end);
1122
1123 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
1124 &su_bh);
1125 if (ret < 0) {
1126 if (ret != -ENOENT)
1127 goto out_sem;
1128 /* hole */
1129 segnum += n;
1130 continue;
1131 }
1132
1133 offset = nilfs_sufile_segment_usage_offset(sufile, segnum,
1134 su_bh);
1135 su = kaddr = kmap_local_folio(su_bh->b_folio, offset);
1136 for (i = 0; i < n; ++i, ++segnum, su = (void *)su + susz) {
1137 if (!nilfs_segment_usage_clean(su))
1138 continue;
1139
1140 nilfs_get_segment_range(nilfs, segnum, &seg_start,
1141 &seg_end);
1142
1143 if (!nblocks) {
1144 /* start new extent */
1145 start = seg_start;
1146 nblocks = seg_end - seg_start + 1;
1147 continue;
1148 }
1149
1150 if (start + nblocks == seg_start) {
1151 /* add to previous extent */
1152 nblocks += seg_end - seg_start + 1;
1153 continue;
1154 }
1155
1156 /* discard previous extent */
1157 if (start < start_block) {
1158 nblocks -= start_block - start;
1159 start = start_block;
1160 }
1161
1162 if (nblocks >= minlen) {
1163 kunmap_local(kaddr);
1164
1165 ret = blkdev_issue_discard(nilfs->ns_bdev,
1166 start * sects_per_block,
1167 nblocks * sects_per_block,
1168 GFP_NOFS);
1169 if (ret < 0) {
1170 put_bh(su_bh);
1171 goto out_sem;
1172 }
1173
1174 ndiscarded += nblocks;
1175 offset = nilfs_sufile_segment_usage_offset(
1176 sufile, segnum, su_bh);
1177 su = kaddr = kmap_local_folio(su_bh->b_folio,
1178 offset);
1179 }
1180
1181 /* start new extent */
1182 start = seg_start;
1183 nblocks = seg_end - seg_start + 1;
1184 }
1185 kunmap_local(kaddr);
1186 put_bh(su_bh);
1187 }
1188
1189
1190 if (nblocks) {
1191 /* discard last extent */
1192 if (start < start_block) {
1193 nblocks -= start_block - start;
1194 start = start_block;
1195 }
1196 if (start + nblocks > end_block + 1)
1197 nblocks = end_block - start + 1;
1198
1199 if (nblocks >= minlen) {
1200 ret = blkdev_issue_discard(nilfs->ns_bdev,
1201 start * sects_per_block,
1202 nblocks * sects_per_block,
1203 GFP_NOFS);
1204 if (!ret)
1205 ndiscarded += nblocks;
1206 }
1207 }
1208
1209out_sem:
1210 up_read(&NILFS_MDT(sufile)->mi_sem);
1211
1212 range->len = ndiscarded << nilfs->ns_blocksize_bits;
1213 return ret;
1214}
1215
1216/**
1217 * nilfs_sufile_read - read or get sufile inode
1218 * @sb: super block instance
1219 * @susize: size of a segment usage entry
1220 * @raw_inode: on-disk sufile inode
1221 * @inodep: buffer to store the inode
1222 */
1223int nilfs_sufile_read(struct super_block *sb, size_t susize,
1224 struct nilfs_inode *raw_inode, struct inode **inodep)
1225{
1226 struct inode *sufile;
1227 struct nilfs_sufile_info *sui;
1228 struct buffer_head *header_bh;
1229 struct nilfs_sufile_header *header;
1230 int err;
1231
1232 if (susize > sb->s_blocksize) {
1233 nilfs_err(sb, "too large segment usage size: %zu bytes",
1234 susize);
1235 return -EINVAL;
1236 } else if (susize < NILFS_MIN_SEGMENT_USAGE_SIZE) {
1237 nilfs_err(sb, "too small segment usage size: %zu bytes",
1238 susize);
1239 return -EINVAL;
1240 }
1241
1242 sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO);
1243 if (unlikely(!sufile))
1244 return -ENOMEM;
1245 if (!(sufile->i_state & I_NEW))
1246 goto out;
1247
1248 err = nilfs_mdt_init(sufile, NILFS_MDT_GFP, sizeof(*sui));
1249 if (err)
1250 goto failed;
1251
1252 nilfs_mdt_set_entry_size(sufile, susize,
1253 sizeof(struct nilfs_sufile_header));
1254
1255 err = nilfs_read_inode_common(sufile, raw_inode);
1256 if (err)
1257 goto failed;
1258
1259 err = nilfs_mdt_get_block(sufile, 0, 0, NULL, &header_bh);
1260 if (unlikely(err)) {
1261 if (err == -ENOENT) {
1262 nilfs_err(sb,
1263 "missing header block in segment usage metadata");
1264 err = -EINVAL;
1265 }
1266 goto failed;
1267 }
1268
1269 sui = NILFS_SUI(sufile);
1270 header = kmap_local_folio(header_bh->b_folio, 0);
1271 sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs);
1272 kunmap_local(header);
1273 brelse(header_bh);
1274
1275 sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1;
1276 sui->allocmin = 0;
1277
1278 unlock_new_inode(sufile);
1279 out:
1280 *inodep = sufile;
1281 return 0;
1282 failed:
1283 iget_failed(sufile);
1284 return err;
1285}
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/**
34 * struct nilfs_sufile_info - on-memory private data of sufile
35 * @mi: on-memory private data of metadata file
36 * @ncleansegs: number of clean segments
37 * @allocmin: lower limit of allocatable segment range
38 * @allocmax: upper limit of allocatable segment range
39 */
40struct nilfs_sufile_info {
41 struct nilfs_mdt_info mi;
42 unsigned long ncleansegs;/* number of clean segments */
43 __u64 allocmin; /* lower limit of allocatable segment range */
44 __u64 allocmax; /* upper limit of allocatable segment range */
45};
46
47static inline struct nilfs_sufile_info *NILFS_SUI(struct inode *sufile)
48{
49 return (struct nilfs_sufile_info *)NILFS_MDT(sufile);
50}
51
52static inline unsigned long
53nilfs_sufile_segment_usages_per_block(const struct inode *sufile)
54{
55 return NILFS_MDT(sufile)->mi_entries_per_block;
56}
57
58static unsigned long
59nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum)
60{
61 __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
62 do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
63 return (unsigned long)t;
64}
65
66static unsigned long
67nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum)
68{
69 __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
70 return do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
71}
72
73static unsigned long
74nilfs_sufile_segment_usages_in_block(const struct inode *sufile, __u64 curr,
75 __u64 max)
76{
77 return min_t(unsigned long,
78 nilfs_sufile_segment_usages_per_block(sufile) -
79 nilfs_sufile_get_offset(sufile, curr),
80 max - curr + 1);
81}
82
83static struct nilfs_segment_usage *
84nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum,
85 struct buffer_head *bh, void *kaddr)
86{
87 return kaddr + bh_offset(bh) +
88 nilfs_sufile_get_offset(sufile, segnum) *
89 NILFS_MDT(sufile)->mi_entry_size;
90}
91
92static inline int nilfs_sufile_get_header_block(struct inode *sufile,
93 struct buffer_head **bhp)
94{
95 return nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);
96}
97
98static inline int
99nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,
100 int create, struct buffer_head **bhp)
101{
102 return nilfs_mdt_get_block(sufile,
103 nilfs_sufile_get_blkoff(sufile, segnum),
104 create, NULL, bhp);
105}
106
107static int nilfs_sufile_delete_segment_usage_block(struct inode *sufile,
108 __u64 segnum)
109{
110 return nilfs_mdt_delete_block(sufile,
111 nilfs_sufile_get_blkoff(sufile, segnum));
112}
113
114static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,
115 u64 ncleanadd, u64 ndirtyadd)
116{
117 struct nilfs_sufile_header *header;
118 void *kaddr;
119
120 kaddr = kmap_atomic(header_bh->b_page);
121 header = kaddr + bh_offset(header_bh);
122 le64_add_cpu(&header->sh_ncleansegs, ncleanadd);
123 le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);
124 kunmap_atomic(kaddr);
125
126 mark_buffer_dirty(header_bh);
127}
128
129/**
130 * nilfs_sufile_get_ncleansegs - return the number of clean segments
131 * @sufile: inode of segment usage file
132 */
133unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile)
134{
135 return NILFS_SUI(sufile)->ncleansegs;
136}
137
138/**
139 * nilfs_sufile_updatev - modify multiple segment usages at a time
140 * @sufile: inode of segment usage file
141 * @segnumv: array of segment numbers
142 * @nsegs: size of @segnumv array
143 * @create: creation flag
144 * @ndone: place to store number of modified segments on @segnumv
145 * @dofunc: primitive operation for the update
146 *
147 * Description: nilfs_sufile_updatev() repeatedly calls @dofunc
148 * against the given array of segments. The @dofunc is called with
149 * buffers of a header block and the sufile block in which the target
150 * segment usage entry is contained. If @ndone is given, the number
151 * of successfully modified segments from the head is stored in the
152 * place @ndone points to.
153 *
154 * Return Value: On success, zero is returned. On error, one of the
155 * following negative error codes is returned.
156 *
157 * %-EIO - I/O error.
158 *
159 * %-ENOMEM - Insufficient amount of memory available.
160 *
161 * %-ENOENT - Given segment usage is in hole block (may be returned if
162 * @create is zero)
163 *
164 * %-EINVAL - Invalid segment usage number
165 */
166int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs,
167 int create, size_t *ndone,
168 void (*dofunc)(struct inode *, __u64,
169 struct buffer_head *,
170 struct buffer_head *))
171{
172 struct buffer_head *header_bh, *bh;
173 unsigned long blkoff, prev_blkoff;
174 __u64 *seg;
175 size_t nerr = 0, n = 0;
176 int ret = 0;
177
178 if (unlikely(nsegs == 0))
179 goto out;
180
181 down_write(&NILFS_MDT(sufile)->mi_sem);
182 for (seg = segnumv; seg < segnumv + nsegs; seg++) {
183 if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) {
184 printk(KERN_WARNING
185 "%s: invalid segment number: %llu\n", __func__,
186 (unsigned long long)*seg);
187 nerr++;
188 }
189 }
190 if (nerr > 0) {
191 ret = -EINVAL;
192 goto out_sem;
193 }
194
195 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
196 if (ret < 0)
197 goto out_sem;
198
199 seg = segnumv;
200 blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
201 ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
202 if (ret < 0)
203 goto out_header;
204
205 for (;;) {
206 dofunc(sufile, *seg, header_bh, bh);
207
208 if (++seg >= segnumv + nsegs)
209 break;
210 prev_blkoff = blkoff;
211 blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
212 if (blkoff == prev_blkoff)
213 continue;
214
215 /* get different block */
216 brelse(bh);
217 ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
218 if (unlikely(ret < 0))
219 goto out_header;
220 }
221 brelse(bh);
222
223 out_header:
224 n = seg - segnumv;
225 brelse(header_bh);
226 out_sem:
227 up_write(&NILFS_MDT(sufile)->mi_sem);
228 out:
229 if (ndone)
230 *ndone = n;
231 return ret;
232}
233
234int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create,
235 void (*dofunc)(struct inode *, __u64,
236 struct buffer_head *,
237 struct buffer_head *))
238{
239 struct buffer_head *header_bh, *bh;
240 int ret;
241
242 if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
243 printk(KERN_WARNING "%s: invalid segment number: %llu\n",
244 __func__, (unsigned long long)segnum);
245 return -EINVAL;
246 }
247 down_write(&NILFS_MDT(sufile)->mi_sem);
248
249 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
250 if (ret < 0)
251 goto out_sem;
252
253 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh);
254 if (!ret) {
255 dofunc(sufile, segnum, header_bh, bh);
256 brelse(bh);
257 }
258 brelse(header_bh);
259
260 out_sem:
261 up_write(&NILFS_MDT(sufile)->mi_sem);
262 return ret;
263}
264
265/**
266 * nilfs_sufile_set_alloc_range - limit range of segment to be allocated
267 * @sufile: inode of segment usage file
268 * @start: minimum segment number of allocatable region (inclusive)
269 * @end: maximum segment number of allocatable region (inclusive)
270 *
271 * Return Value: On success, 0 is returned. On error, one of the
272 * following negative error codes is returned.
273 *
274 * %-ERANGE - invalid segment region
275 */
276int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end)
277{
278 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
279 __u64 nsegs;
280 int ret = -ERANGE;
281
282 down_write(&NILFS_MDT(sufile)->mi_sem);
283 nsegs = nilfs_sufile_get_nsegments(sufile);
284
285 if (start <= end && end < nsegs) {
286 sui->allocmin = start;
287 sui->allocmax = end;
288 ret = 0;
289 }
290 up_write(&NILFS_MDT(sufile)->mi_sem);
291 return ret;
292}
293
294/**
295 * nilfs_sufile_alloc - allocate a segment
296 * @sufile: inode of segment usage file
297 * @segnump: pointer to segment number
298 *
299 * Description: nilfs_sufile_alloc() allocates a clean segment.
300 *
301 * Return Value: On success, 0 is returned and the segment number of the
302 * allocated segment is stored in the place pointed by @segnump. On error, one
303 * of the following negative error codes is returned.
304 *
305 * %-EIO - I/O error.
306 *
307 * %-ENOMEM - Insufficient amount of memory available.
308 *
309 * %-ENOSPC - No clean segment left.
310 */
311int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
312{
313 struct buffer_head *header_bh, *su_bh;
314 struct nilfs_sufile_header *header;
315 struct nilfs_segment_usage *su;
316 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
317 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
318 __u64 segnum, maxsegnum, last_alloc;
319 void *kaddr;
320 unsigned long nsegments, ncleansegs, nsus, cnt;
321 int ret, j;
322
323 down_write(&NILFS_MDT(sufile)->mi_sem);
324
325 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
326 if (ret < 0)
327 goto out_sem;
328 kaddr = kmap_atomic(header_bh->b_page);
329 header = kaddr + bh_offset(header_bh);
330 ncleansegs = le64_to_cpu(header->sh_ncleansegs);
331 last_alloc = le64_to_cpu(header->sh_last_alloc);
332 kunmap_atomic(kaddr);
333
334 nsegments = nilfs_sufile_get_nsegments(sufile);
335 maxsegnum = sui->allocmax;
336 segnum = last_alloc + 1;
337 if (segnum < sui->allocmin || segnum > sui->allocmax)
338 segnum = sui->allocmin;
339
340 for (cnt = 0; cnt < nsegments; cnt += nsus) {
341 if (segnum > maxsegnum) {
342 if (cnt < sui->allocmax - sui->allocmin + 1) {
343 /*
344 * wrap around in the limited region.
345 * if allocation started from
346 * sui->allocmin, this never happens.
347 */
348 segnum = sui->allocmin;
349 maxsegnum = last_alloc;
350 } else if (segnum > sui->allocmin &&
351 sui->allocmax + 1 < nsegments) {
352 segnum = sui->allocmax + 1;
353 maxsegnum = nsegments - 1;
354 } else if (sui->allocmin > 0) {
355 segnum = 0;
356 maxsegnum = sui->allocmin - 1;
357 } else {
358 break; /* never happens */
359 }
360 }
361 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
362 &su_bh);
363 if (ret < 0)
364 goto out_header;
365 kaddr = kmap_atomic(su_bh->b_page);
366 su = nilfs_sufile_block_get_segment_usage(
367 sufile, segnum, su_bh, kaddr);
368
369 nsus = nilfs_sufile_segment_usages_in_block(
370 sufile, segnum, maxsegnum);
371 for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
372 if (!nilfs_segment_usage_clean(su))
373 continue;
374 /* found a clean segment */
375 nilfs_segment_usage_set_dirty(su);
376 kunmap_atomic(kaddr);
377
378 kaddr = kmap_atomic(header_bh->b_page);
379 header = kaddr + bh_offset(header_bh);
380 le64_add_cpu(&header->sh_ncleansegs, -1);
381 le64_add_cpu(&header->sh_ndirtysegs, 1);
382 header->sh_last_alloc = cpu_to_le64(segnum);
383 kunmap_atomic(kaddr);
384
385 sui->ncleansegs--;
386 mark_buffer_dirty(header_bh);
387 mark_buffer_dirty(su_bh);
388 nilfs_mdt_mark_dirty(sufile);
389 brelse(su_bh);
390 *segnump = segnum;
391 goto out_header;
392 }
393
394 kunmap_atomic(kaddr);
395 brelse(su_bh);
396 }
397
398 /* no segments left */
399 ret = -ENOSPC;
400
401 out_header:
402 brelse(header_bh);
403
404 out_sem:
405 up_write(&NILFS_MDT(sufile)->mi_sem);
406 return ret;
407}
408
409void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,
410 struct buffer_head *header_bh,
411 struct buffer_head *su_bh)
412{
413 struct nilfs_segment_usage *su;
414 void *kaddr;
415
416 kaddr = kmap_atomic(su_bh->b_page);
417 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
418 if (unlikely(!nilfs_segment_usage_clean(su))) {
419 printk(KERN_WARNING "%s: segment %llu must be clean\n",
420 __func__, (unsigned long long)segnum);
421 kunmap_atomic(kaddr);
422 return;
423 }
424 nilfs_segment_usage_set_dirty(su);
425 kunmap_atomic(kaddr);
426
427 nilfs_sufile_mod_counter(header_bh, -1, 1);
428 NILFS_SUI(sufile)->ncleansegs--;
429
430 mark_buffer_dirty(su_bh);
431 nilfs_mdt_mark_dirty(sufile);
432}
433
434void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,
435 struct buffer_head *header_bh,
436 struct buffer_head *su_bh)
437{
438 struct nilfs_segment_usage *su;
439 void *kaddr;
440 int clean, dirty;
441
442 kaddr = kmap_atomic(su_bh->b_page);
443 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
444 if (su->su_flags == cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY) &&
445 su->su_nblocks == cpu_to_le32(0)) {
446 kunmap_atomic(kaddr);
447 return;
448 }
449 clean = nilfs_segment_usage_clean(su);
450 dirty = nilfs_segment_usage_dirty(su);
451
452 /* make the segment garbage */
453 su->su_lastmod = cpu_to_le64(0);
454 su->su_nblocks = cpu_to_le32(0);
455 su->su_flags = cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY);
456 kunmap_atomic(kaddr);
457
458 nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);
459 NILFS_SUI(sufile)->ncleansegs -= clean;
460
461 mark_buffer_dirty(su_bh);
462 nilfs_mdt_mark_dirty(sufile);
463}
464
465void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,
466 struct buffer_head *header_bh,
467 struct buffer_head *su_bh)
468{
469 struct nilfs_segment_usage *su;
470 void *kaddr;
471 int sudirty;
472
473 kaddr = kmap_atomic(su_bh->b_page);
474 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
475 if (nilfs_segment_usage_clean(su)) {
476 printk(KERN_WARNING "%s: segment %llu is already clean\n",
477 __func__, (unsigned long long)segnum);
478 kunmap_atomic(kaddr);
479 return;
480 }
481 WARN_ON(nilfs_segment_usage_error(su));
482 WARN_ON(!nilfs_segment_usage_dirty(su));
483
484 sudirty = nilfs_segment_usage_dirty(su);
485 nilfs_segment_usage_set_clean(su);
486 kunmap_atomic(kaddr);
487 mark_buffer_dirty(su_bh);
488
489 nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);
490 NILFS_SUI(sufile)->ncleansegs++;
491
492 nilfs_mdt_mark_dirty(sufile);
493}
494
495/**
496 * nilfs_sufile_mark_dirty - mark the buffer having a segment usage dirty
497 * @sufile: inode of segment usage file
498 * @segnum: segment number
499 */
500int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)
501{
502 struct buffer_head *bh;
503 int ret;
504
505 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
506 if (!ret) {
507 mark_buffer_dirty(bh);
508 nilfs_mdt_mark_dirty(sufile);
509 brelse(bh);
510 }
511 return ret;
512}
513
514/**
515 * nilfs_sufile_set_segment_usage - set usage of a segment
516 * @sufile: inode of segment usage file
517 * @segnum: segment number
518 * @nblocks: number of live blocks in the segment
519 * @modtime: modification time (option)
520 */
521int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
522 unsigned long nblocks, time_t modtime)
523{
524 struct buffer_head *bh;
525 struct nilfs_segment_usage *su;
526 void *kaddr;
527 int ret;
528
529 down_write(&NILFS_MDT(sufile)->mi_sem);
530 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
531 if (ret < 0)
532 goto out_sem;
533
534 kaddr = kmap_atomic(bh->b_page);
535 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);
536 WARN_ON(nilfs_segment_usage_error(su));
537 if (modtime)
538 su->su_lastmod = cpu_to_le64(modtime);
539 su->su_nblocks = cpu_to_le32(nblocks);
540 kunmap_atomic(kaddr);
541
542 mark_buffer_dirty(bh);
543 nilfs_mdt_mark_dirty(sufile);
544 brelse(bh);
545
546 out_sem:
547 up_write(&NILFS_MDT(sufile)->mi_sem);
548 return ret;
549}
550
551/**
552 * nilfs_sufile_get_stat - get segment usage statistics
553 * @sufile: inode of segment usage file
554 * @stat: pointer to a structure of segment usage statistics
555 *
556 * Description: nilfs_sufile_get_stat() returns information about segment
557 * usage.
558 *
559 * Return Value: On success, 0 is returned, and segment usage information is
560 * stored in the place pointed by @stat. On error, one of the following
561 * negative error codes is returned.
562 *
563 * %-EIO - I/O error.
564 *
565 * %-ENOMEM - Insufficient amount of memory available.
566 */
567int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat)
568{
569 struct buffer_head *header_bh;
570 struct nilfs_sufile_header *header;
571 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
572 void *kaddr;
573 int ret;
574
575 down_read(&NILFS_MDT(sufile)->mi_sem);
576
577 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
578 if (ret < 0)
579 goto out_sem;
580
581 kaddr = kmap_atomic(header_bh->b_page);
582 header = kaddr + bh_offset(header_bh);
583 sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile);
584 sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs);
585 sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs);
586 sustat->ss_ctime = nilfs->ns_ctime;
587 sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime;
588 spin_lock(&nilfs->ns_last_segment_lock);
589 sustat->ss_prot_seq = nilfs->ns_prot_seq;
590 spin_unlock(&nilfs->ns_last_segment_lock);
591 kunmap_atomic(kaddr);
592 brelse(header_bh);
593
594 out_sem:
595 up_read(&NILFS_MDT(sufile)->mi_sem);
596 return ret;
597}
598
599void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
600 struct buffer_head *header_bh,
601 struct buffer_head *su_bh)
602{
603 struct nilfs_segment_usage *su;
604 void *kaddr;
605 int suclean;
606
607 kaddr = kmap_atomic(su_bh->b_page);
608 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
609 if (nilfs_segment_usage_error(su)) {
610 kunmap_atomic(kaddr);
611 return;
612 }
613 suclean = nilfs_segment_usage_clean(su);
614 nilfs_segment_usage_set_error(su);
615 kunmap_atomic(kaddr);
616
617 if (suclean) {
618 nilfs_sufile_mod_counter(header_bh, -1, 0);
619 NILFS_SUI(sufile)->ncleansegs--;
620 }
621 mark_buffer_dirty(su_bh);
622 nilfs_mdt_mark_dirty(sufile);
623}
624
625/**
626 * nilfs_sufile_truncate_range - truncate range of segment array
627 * @sufile: inode of segment usage file
628 * @start: start segment number (inclusive)
629 * @end: end segment number (inclusive)
630 *
631 * Return Value: On success, 0 is returned. On error, one of the
632 * following negative error codes is returned.
633 *
634 * %-EIO - I/O error.
635 *
636 * %-ENOMEM - Insufficient amount of memory available.
637 *
638 * %-EINVAL - Invalid number of segments specified
639 *
640 * %-EBUSY - Dirty or active segments are present in the range
641 */
642static int nilfs_sufile_truncate_range(struct inode *sufile,
643 __u64 start, __u64 end)
644{
645 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
646 struct buffer_head *header_bh;
647 struct buffer_head *su_bh;
648 struct nilfs_segment_usage *su, *su2;
649 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
650 unsigned long segusages_per_block;
651 unsigned long nsegs, ncleaned;
652 __u64 segnum;
653 void *kaddr;
654 ssize_t n, nc;
655 int ret;
656 int j;
657
658 nsegs = nilfs_sufile_get_nsegments(sufile);
659
660 ret = -EINVAL;
661 if (start > end || start >= nsegs)
662 goto out;
663
664 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
665 if (ret < 0)
666 goto out;
667
668 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
669 ncleaned = 0;
670
671 for (segnum = start; segnum <= end; segnum += n) {
672 n = min_t(unsigned long,
673 segusages_per_block -
674 nilfs_sufile_get_offset(sufile, segnum),
675 end - segnum + 1);
676 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
677 &su_bh);
678 if (ret < 0) {
679 if (ret != -ENOENT)
680 goto out_header;
681 /* hole */
682 continue;
683 }
684 kaddr = kmap_atomic(su_bh->b_page);
685 su = nilfs_sufile_block_get_segment_usage(
686 sufile, segnum, su_bh, kaddr);
687 su2 = su;
688 for (j = 0; j < n; j++, su = (void *)su + susz) {
689 if ((le32_to_cpu(su->su_flags) &
690 ~(1UL << NILFS_SEGMENT_USAGE_ERROR)) ||
691 nilfs_segment_is_active(nilfs, segnum + j)) {
692 ret = -EBUSY;
693 kunmap_atomic(kaddr);
694 brelse(su_bh);
695 goto out_header;
696 }
697 }
698 nc = 0;
699 for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) {
700 if (nilfs_segment_usage_error(su)) {
701 nilfs_segment_usage_set_clean(su);
702 nc++;
703 }
704 }
705 kunmap_atomic(kaddr);
706 if (nc > 0) {
707 mark_buffer_dirty(su_bh);
708 ncleaned += nc;
709 }
710 brelse(su_bh);
711
712 if (n == segusages_per_block) {
713 /* make hole */
714 nilfs_sufile_delete_segment_usage_block(sufile, segnum);
715 }
716 }
717 ret = 0;
718
719out_header:
720 if (ncleaned > 0) {
721 NILFS_SUI(sufile)->ncleansegs += ncleaned;
722 nilfs_sufile_mod_counter(header_bh, ncleaned, 0);
723 nilfs_mdt_mark_dirty(sufile);
724 }
725 brelse(header_bh);
726out:
727 return ret;
728}
729
730/**
731 * nilfs_sufile_resize - resize segment array
732 * @sufile: inode of segment usage file
733 * @newnsegs: new number of segments
734 *
735 * Return Value: On success, 0 is returned. On error, one of the
736 * following negative error codes is returned.
737 *
738 * %-EIO - I/O error.
739 *
740 * %-ENOMEM - Insufficient amount of memory available.
741 *
742 * %-ENOSPC - Enough free space is not left for shrinking
743 *
744 * %-EBUSY - Dirty or active segments exist in the region to be truncated
745 */
746int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs)
747{
748 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
749 struct buffer_head *header_bh;
750 struct nilfs_sufile_header *header;
751 struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
752 void *kaddr;
753 unsigned long nsegs, nrsvsegs;
754 int ret = 0;
755
756 down_write(&NILFS_MDT(sufile)->mi_sem);
757
758 nsegs = nilfs_sufile_get_nsegments(sufile);
759 if (nsegs == newnsegs)
760 goto out;
761
762 ret = -ENOSPC;
763 nrsvsegs = nilfs_nrsvsegs(nilfs, newnsegs);
764 if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs)
765 goto out;
766
767 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
768 if (ret < 0)
769 goto out;
770
771 if (newnsegs > nsegs) {
772 sui->ncleansegs += newnsegs - nsegs;
773 } else /* newnsegs < nsegs */ {
774 ret = nilfs_sufile_truncate_range(sufile, newnsegs, nsegs - 1);
775 if (ret < 0)
776 goto out_header;
777
778 sui->ncleansegs -= nsegs - newnsegs;
779 }
780
781 kaddr = kmap_atomic(header_bh->b_page);
782 header = kaddr + bh_offset(header_bh);
783 header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs);
784 kunmap_atomic(kaddr);
785
786 mark_buffer_dirty(header_bh);
787 nilfs_mdt_mark_dirty(sufile);
788 nilfs_set_nsegments(nilfs, newnsegs);
789
790out_header:
791 brelse(header_bh);
792out:
793 up_write(&NILFS_MDT(sufile)->mi_sem);
794 return ret;
795}
796
797/**
798 * nilfs_sufile_get_suinfo -
799 * @sufile: inode of segment usage file
800 * @segnum: segment number to start looking
801 * @buf: array of suinfo
802 * @sisz: byte size of suinfo
803 * @nsi: size of suinfo array
804 *
805 * Description:
806 *
807 * Return Value: On success, 0 is returned and .... On error, one of the
808 * following negative error codes is returned.
809 *
810 * %-EIO - I/O error.
811 *
812 * %-ENOMEM - Insufficient amount of memory available.
813 */
814ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
815 unsigned sisz, size_t nsi)
816{
817 struct buffer_head *su_bh;
818 struct nilfs_segment_usage *su;
819 struct nilfs_suinfo *si = buf;
820 size_t susz = NILFS_MDT(sufile)->mi_entry_size;
821 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
822 void *kaddr;
823 unsigned long nsegs, segusages_per_block;
824 ssize_t n;
825 int ret, i, j;
826
827 down_read(&NILFS_MDT(sufile)->mi_sem);
828
829 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
830 nsegs = min_t(unsigned long,
831 nilfs_sufile_get_nsegments(sufile) - segnum,
832 nsi);
833 for (i = 0; i < nsegs; i += n, segnum += n) {
834 n = min_t(unsigned long,
835 segusages_per_block -
836 nilfs_sufile_get_offset(sufile, segnum),
837 nsegs - i);
838 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
839 &su_bh);
840 if (ret < 0) {
841 if (ret != -ENOENT)
842 goto out;
843 /* hole */
844 memset(si, 0, sisz * n);
845 si = (void *)si + sisz * n;
846 continue;
847 }
848
849 kaddr = kmap_atomic(su_bh->b_page);
850 su = nilfs_sufile_block_get_segment_usage(
851 sufile, segnum, su_bh, kaddr);
852 for (j = 0; j < n;
853 j++, su = (void *)su + susz, si = (void *)si + sisz) {
854 si->sui_lastmod = le64_to_cpu(su->su_lastmod);
855 si->sui_nblocks = le32_to_cpu(su->su_nblocks);
856 si->sui_flags = le32_to_cpu(su->su_flags) &
857 ~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
858 if (nilfs_segment_is_active(nilfs, segnum + j))
859 si->sui_flags |=
860 (1UL << NILFS_SEGMENT_USAGE_ACTIVE);
861 }
862 kunmap_atomic(kaddr);
863 brelse(su_bh);
864 }
865 ret = nsegs;
866
867 out:
868 up_read(&NILFS_MDT(sufile)->mi_sem);
869 return ret;
870}
871
872/**
873 * nilfs_sufile_set_suinfo - sets segment usage info
874 * @sufile: inode of segment usage file
875 * @buf: array of suinfo_update
876 * @supsz: byte size of suinfo_update
877 * @nsup: size of suinfo_update array
878 *
879 * Description: Takes an array of nilfs_suinfo_update structs and updates
880 * segment usage accordingly. Only the fields indicated by the sup_flags
881 * are updated.
882 *
883 * Return Value: On success, 0 is returned. On error, one of the
884 * following negative error codes is returned.
885 *
886 * %-EIO - I/O error.
887 *
888 * %-ENOMEM - Insufficient amount of memory available.
889 *
890 * %-EINVAL - Invalid values in input (segment number, flags or nblocks)
891 */
892ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf,
893 unsigned supsz, size_t nsup)
894{
895 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
896 struct buffer_head *header_bh, *bh;
897 struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup;
898 struct nilfs_segment_usage *su;
899 void *kaddr;
900 unsigned long blkoff, prev_blkoff;
901 int cleansi, cleansu, dirtysi, dirtysu;
902 long ncleaned = 0, ndirtied = 0;
903 int ret = 0;
904
905 if (unlikely(nsup == 0))
906 return ret;
907
908 for (sup = buf; sup < supend; sup = (void *)sup + supsz) {
909 if (sup->sup_segnum >= nilfs->ns_nsegments
910 || (sup->sup_flags &
911 (~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS))
912 || (nilfs_suinfo_update_nblocks(sup) &&
913 sup->sup_sui.sui_nblocks >
914 nilfs->ns_blocks_per_segment))
915 return -EINVAL;
916 }
917
918 down_write(&NILFS_MDT(sufile)->mi_sem);
919
920 ret = nilfs_sufile_get_header_block(sufile, &header_bh);
921 if (ret < 0)
922 goto out_sem;
923
924 sup = buf;
925 blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
926 ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
927 if (ret < 0)
928 goto out_header;
929
930 for (;;) {
931 kaddr = kmap_atomic(bh->b_page);
932 su = nilfs_sufile_block_get_segment_usage(
933 sufile, sup->sup_segnum, bh, kaddr);
934
935 if (nilfs_suinfo_update_lastmod(sup))
936 su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod);
937
938 if (nilfs_suinfo_update_nblocks(sup))
939 su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks);
940
941 if (nilfs_suinfo_update_flags(sup)) {
942 /*
943 * Active flag is a virtual flag projected by running
944 * nilfs kernel code - drop it not to write it to
945 * disk.
946 */
947 sup->sup_sui.sui_flags &=
948 ~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
949
950 cleansi = nilfs_suinfo_clean(&sup->sup_sui);
951 cleansu = nilfs_segment_usage_clean(su);
952 dirtysi = nilfs_suinfo_dirty(&sup->sup_sui);
953 dirtysu = nilfs_segment_usage_dirty(su);
954
955 if (cleansi && !cleansu)
956 ++ncleaned;
957 else if (!cleansi && cleansu)
958 --ncleaned;
959
960 if (dirtysi && !dirtysu)
961 ++ndirtied;
962 else if (!dirtysi && dirtysu)
963 --ndirtied;
964
965 su->su_flags = cpu_to_le32(sup->sup_sui.sui_flags);
966 }
967
968 kunmap_atomic(kaddr);
969
970 sup = (void *)sup + supsz;
971 if (sup >= supend)
972 break;
973
974 prev_blkoff = blkoff;
975 blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
976 if (blkoff == prev_blkoff)
977 continue;
978
979 /* get different block */
980 mark_buffer_dirty(bh);
981 put_bh(bh);
982 ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
983 if (unlikely(ret < 0))
984 goto out_mark;
985 }
986 mark_buffer_dirty(bh);
987 put_bh(bh);
988
989 out_mark:
990 if (ncleaned || ndirtied) {
991 nilfs_sufile_mod_counter(header_bh, (u64)ncleaned,
992 (u64)ndirtied);
993 NILFS_SUI(sufile)->ncleansegs += ncleaned;
994 }
995 nilfs_mdt_mark_dirty(sufile);
996 out_header:
997 put_bh(header_bh);
998 out_sem:
999 up_write(&NILFS_MDT(sufile)->mi_sem);
1000 return ret;
1001}
1002
1003/**
1004 * nilfs_sufile_trim_fs() - trim ioctl handle function
1005 * @sufile: inode of segment usage file
1006 * @range: fstrim_range structure
1007 *
1008 * start: First Byte to trim
1009 * len: number of Bytes to trim from start
1010 * minlen: minimum extent length in Bytes
1011 *
1012 * Decription: nilfs_sufile_trim_fs goes through all segments containing bytes
1013 * from start to start+len. start is rounded up to the next block boundary
1014 * and start+len is rounded down. For each clean segment blkdev_issue_discard
1015 * function is invoked.
1016 *
1017 * Return Value: On success, 0 is returned or negative error code, otherwise.
1018 */
1019int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)
1020{
1021 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
1022 struct buffer_head *su_bh;
1023 struct nilfs_segment_usage *su;
1024 void *kaddr;
1025 size_t n, i, susz = NILFS_MDT(sufile)->mi_entry_size;
1026 sector_t seg_start, seg_end, start_block, end_block;
1027 sector_t start = 0, nblocks = 0;
1028 u64 segnum, segnum_end, minlen, len, max_blocks, ndiscarded = 0;
1029 int ret = 0;
1030 unsigned int sects_per_block;
1031
1032 sects_per_block = (1 << nilfs->ns_blocksize_bits) /
1033 bdev_logical_block_size(nilfs->ns_bdev);
1034 len = range->len >> nilfs->ns_blocksize_bits;
1035 minlen = range->minlen >> nilfs->ns_blocksize_bits;
1036 max_blocks = ((u64)nilfs->ns_nsegments * nilfs->ns_blocks_per_segment);
1037
1038 if (!len || range->start >= max_blocks << nilfs->ns_blocksize_bits)
1039 return -EINVAL;
1040
1041 start_block = (range->start + nilfs->ns_blocksize - 1) >>
1042 nilfs->ns_blocksize_bits;
1043
1044 /*
1045 * range->len can be very large (actually, it is set to
1046 * ULLONG_MAX by default) - truncate upper end of the range
1047 * carefully so as not to overflow.
1048 */
1049 if (max_blocks - start_block < len)
1050 end_block = max_blocks - 1;
1051 else
1052 end_block = start_block + len - 1;
1053
1054 segnum = nilfs_get_segnum_of_block(nilfs, start_block);
1055 segnum_end = nilfs_get_segnum_of_block(nilfs, end_block);
1056
1057 down_read(&NILFS_MDT(sufile)->mi_sem);
1058
1059 while (segnum <= segnum_end) {
1060 n = nilfs_sufile_segment_usages_in_block(sufile, segnum,
1061 segnum_end);
1062
1063 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
1064 &su_bh);
1065 if (ret < 0) {
1066 if (ret != -ENOENT)
1067 goto out_sem;
1068 /* hole */
1069 segnum += n;
1070 continue;
1071 }
1072
1073 kaddr = kmap_atomic(su_bh->b_page);
1074 su = nilfs_sufile_block_get_segment_usage(sufile, segnum,
1075 su_bh, kaddr);
1076 for (i = 0; i < n; ++i, ++segnum, su = (void *)su + susz) {
1077 if (!nilfs_segment_usage_clean(su))
1078 continue;
1079
1080 nilfs_get_segment_range(nilfs, segnum, &seg_start,
1081 &seg_end);
1082
1083 if (!nblocks) {
1084 /* start new extent */
1085 start = seg_start;
1086 nblocks = seg_end - seg_start + 1;
1087 continue;
1088 }
1089
1090 if (start + nblocks == seg_start) {
1091 /* add to previous extent */
1092 nblocks += seg_end - seg_start + 1;
1093 continue;
1094 }
1095
1096 /* discard previous extent */
1097 if (start < start_block) {
1098 nblocks -= start_block - start;
1099 start = start_block;
1100 }
1101
1102 if (nblocks >= minlen) {
1103 kunmap_atomic(kaddr);
1104
1105 ret = blkdev_issue_discard(nilfs->ns_bdev,
1106 start * sects_per_block,
1107 nblocks * sects_per_block,
1108 GFP_NOFS, 0);
1109 if (ret < 0) {
1110 put_bh(su_bh);
1111 goto out_sem;
1112 }
1113
1114 ndiscarded += nblocks;
1115 kaddr = kmap_atomic(su_bh->b_page);
1116 su = nilfs_sufile_block_get_segment_usage(
1117 sufile, segnum, su_bh, kaddr);
1118 }
1119
1120 /* start new extent */
1121 start = seg_start;
1122 nblocks = seg_end - seg_start + 1;
1123 }
1124 kunmap_atomic(kaddr);
1125 put_bh(su_bh);
1126 }
1127
1128
1129 if (nblocks) {
1130 /* discard last extent */
1131 if (start < start_block) {
1132 nblocks -= start_block - start;
1133 start = start_block;
1134 }
1135 if (start + nblocks > end_block + 1)
1136 nblocks = end_block - start + 1;
1137
1138 if (nblocks >= minlen) {
1139 ret = blkdev_issue_discard(nilfs->ns_bdev,
1140 start * sects_per_block,
1141 nblocks * sects_per_block,
1142 GFP_NOFS, 0);
1143 if (!ret)
1144 ndiscarded += nblocks;
1145 }
1146 }
1147
1148out_sem:
1149 up_read(&NILFS_MDT(sufile)->mi_sem);
1150
1151 range->len = ndiscarded << nilfs->ns_blocksize_bits;
1152 return ret;
1153}
1154
1155/**
1156 * nilfs_sufile_read - read or get sufile inode
1157 * @sb: super block instance
1158 * @susize: size of a segment usage entry
1159 * @raw_inode: on-disk sufile inode
1160 * @inodep: buffer to store the inode
1161 */
1162int nilfs_sufile_read(struct super_block *sb, size_t susize,
1163 struct nilfs_inode *raw_inode, struct inode **inodep)
1164{
1165 struct inode *sufile;
1166 struct nilfs_sufile_info *sui;
1167 struct buffer_head *header_bh;
1168 struct nilfs_sufile_header *header;
1169 void *kaddr;
1170 int err;
1171
1172 if (susize > sb->s_blocksize) {
1173 printk(KERN_ERR
1174 "NILFS: too large segment usage size: %zu bytes.\n",
1175 susize);
1176 return -EINVAL;
1177 } else if (susize < NILFS_MIN_SEGMENT_USAGE_SIZE) {
1178 printk(KERN_ERR
1179 "NILFS: too small segment usage size: %zu bytes.\n",
1180 susize);
1181 return -EINVAL;
1182 }
1183
1184 sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO);
1185 if (unlikely(!sufile))
1186 return -ENOMEM;
1187 if (!(sufile->i_state & I_NEW))
1188 goto out;
1189
1190 err = nilfs_mdt_init(sufile, NILFS_MDT_GFP, sizeof(*sui));
1191 if (err)
1192 goto failed;
1193
1194 nilfs_mdt_set_entry_size(sufile, susize,
1195 sizeof(struct nilfs_sufile_header));
1196
1197 err = nilfs_read_inode_common(sufile, raw_inode);
1198 if (err)
1199 goto failed;
1200
1201 err = nilfs_sufile_get_header_block(sufile, &header_bh);
1202 if (err)
1203 goto failed;
1204
1205 sui = NILFS_SUI(sufile);
1206 kaddr = kmap_atomic(header_bh->b_page);
1207 header = kaddr + bh_offset(header_bh);
1208 sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs);
1209 kunmap_atomic(kaddr);
1210 brelse(header_bh);
1211
1212 sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1;
1213 sui->allocmin = 0;
1214
1215 unlock_new_inode(sufile);
1216 out:
1217 *inodep = sufile;
1218 return 0;
1219 failed:
1220 iget_failed(sufile);
1221 return err;
1222}