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(inode: sufile);
38}
39
40static inline unsigned long
41nilfs_sufile_segment_usages_per_block(const struct inode *sufile)
42{
43 return NILFS_MDT(inode: 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(inode: 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(inode: 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(inode: 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(page: header_bh->b_page);
111 header = kaddr + bh_offset(bh: header_bh);
112 le64_add_cpu(var: &header->sh_ncleansegs, val: ncleanadd);
113 le64_add_cpu(var: &header->sh_ndirtysegs, val: ndirtyadd);
114 kunmap_atomic(kaddr);
115
116 mark_buffer_dirty(bh: 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(sem: &NILFS_MDT(inode: 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, bhp: &header_bh);
186 if (ret < 0)
187 goto out_sem;
188
189 seg = segnumv;
190 blkoff = nilfs_sufile_get_blkoff(sufile, segnum: *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, segnum: *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(bh: header_bh);
216 out_sem:
217 up_write(sem: &NILFS_MDT(inode: 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(sem: &NILFS_MDT(inode: sufile)->mi_sem);
238
239 ret = nilfs_sufile_get_header_block(sufile, bhp: &header_bh);
240 if (ret < 0)
241 goto out_sem;
242
243 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, bhp: &bh);
244 if (!ret) {
245 dofunc(sufile, segnum, header_bh, bh);
246 brelse(bh);
247 }
248 brelse(bh: header_bh);
249
250 out_sem:
251 up_write(sem: &NILFS_MDT(inode: 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(sem: &NILFS_MDT(inode: 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(sem: &NILFS_MDT(inode: 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(inode: 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(sem: &NILFS_MDT(inode: sufile)->mi_sem);
314
315 ret = nilfs_sufile_get_header_block(sufile, bhp: &header_bh);
316 if (ret < 0)
317 goto out_sem;
318 kaddr = kmap_atomic(page: header_bh->b_page);
319 header = kaddr + bh_offset(bh: 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, create: 1,
352 bhp: &su_bh);
353 if (ret < 0)
354 goto out_header;
355 kaddr = kmap_atomic(page: su_bh->b_page);
356 su = nilfs_sufile_block_get_segment_usage(
357 sufile, segnum, bh: su_bh, kaddr);
358
359 nsus = nilfs_sufile_segment_usages_in_block(
360 sufile, curr: segnum, max: 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(page: header_bh->b_page);
369 header = kaddr + bh_offset(bh: header_bh);
370 le64_add_cpu(var: &header->sh_ncleansegs, val: -1);
371 le64_add_cpu(var: &header->sh_ndirtysegs, val: 1);
372 header->sh_last_alloc = cpu_to_le64(segnum);
373 kunmap_atomic(kaddr);
374
375 sui->ncleansegs--;
376 mark_buffer_dirty(bh: header_bh);
377 mark_buffer_dirty(bh: su_bh);
378 nilfs_mdt_mark_dirty(inode: sufile);
379 brelse(bh: 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(bh: su_bh);
389 }
390
391 /* no segments left */
392 ret = -ENOSPC;
393
394 out_header:
395 brelse(bh: header_bh);
396
397 out_sem:
398 up_write(sem: &NILFS_MDT(inode: 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(page: su_bh->b_page);
410 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh: 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, ncleanadd: -1, ndirtyadd: 1);
421 NILFS_SUI(sufile)->ncleansegs--;
422
423 mark_buffer_dirty(bh: su_bh);
424 nilfs_mdt_mark_dirty(inode: 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(page: su_bh->b_page);
436 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh: 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, ncleanadd: clean ? (u64)-1 : 0, ndirtyadd: dirty ? 0 : 1);
452 NILFS_SUI(sufile)->ncleansegs -= clean;
453
454 mark_buffer_dirty(bh: su_bh);
455 nilfs_mdt_mark_dirty(inode: 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(page: su_bh->b_page);
467 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh: 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(bh: su_bh);
481
482 nilfs_sufile_mod_counter(header_bh, ncleanadd: 1, ndirtyadd: sudirty ? (u64)-1 : 0);
483 NILFS_SUI(sufile)->ncleansegs++;
484
485 nilfs_mdt_mark_dirty(inode: 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(sem: &NILFS_MDT(inode: sufile)->mi_sem);
503 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create: 0, bhp: &bh);
504 if (!ret) {
505 mark_buffer_dirty(bh);
506 nilfs_mdt_mark_dirty(inode: sufile);
507 kaddr = kmap_atomic(page: 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(sem: &NILFS_MDT(inode: 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(sem: &NILFS_MDT(inode: sufile)->mi_sem);
533 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create: 0, bhp: &bh);
534 if (ret < 0)
535 goto out_sem;
536
537 kaddr = kmap_atomic(page: 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(inode: sufile);
547 brelse(bh);
548
549 out_sem:
550 up_write(sem: &NILFS_MDT(inode: 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(sem: &NILFS_MDT(inode: sufile)->mi_sem);
579
580 ret = nilfs_sufile_get_header_block(sufile, bhp: &header_bh);
581 if (ret < 0)
582 goto out_sem;
583
584 kaddr = kmap_atomic(page: header_bh->b_page);
585 header = kaddr + bh_offset(bh: 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(lock: &nilfs->ns_last_segment_lock);
592 sustat->ss_prot_seq = nilfs->ns_prot_seq;
593 spin_unlock(lock: &nilfs->ns_last_segment_lock);
594 kunmap_atomic(kaddr);
595 brelse(bh: header_bh);
596
597 out_sem:
598 up_read(sem: &NILFS_MDT(inode: 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(page: su_bh->b_page);
611 su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh: 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, ncleanadd: -1, ndirtyadd: 0);
622 NILFS_SUI(sufile)->ncleansegs--;
623 }
624 mark_buffer_dirty(bh: su_bh);
625 nilfs_mdt_mark_dirty(inode: 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(inode: 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, bhp: &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, create: 0,
680 bhp: &su_bh);
681 if (ret < 0) {
682 if (ret != -ENOENT)
683 goto out_header;
684 /* hole */
685 continue;
686 }
687 kaddr = kmap_atomic(page: su_bh->b_page);
688 su = nilfs_sufile_block_get_segment_usage(
689 sufile, segnum, bh: 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, n: segnum + j)) {
695 ret = -EBUSY;
696 kunmap_atomic(kaddr);
697 brelse(bh: 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(bh: su_bh);
711 ncleaned += nc;
712 }
713 brelse(bh: 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, ncleanadd: ncleaned, ndirtyadd: 0);
726 nilfs_mdt_mark_dirty(inode: sufile);
727 }
728 brelse(bh: 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(sem: &NILFS_MDT(inode: 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, nsegs: newnsegs);
767 if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs)
768 goto out;
769
770 ret = nilfs_sufile_get_header_block(sufile, bhp: &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, start: newnsegs, end: nsegs - 1);
778 if (ret < 0)
779 goto out_header;
780
781 sui->ncleansegs -= nsegs - newnsegs;
782
783 /*
784 * If the sufile is successfully truncated, immediately adjust
785 * the segment allocation space while locking the semaphore
786 * "mi_sem" so that nilfs_sufile_alloc() never allocates
787 * segments in the truncated space.
788 */
789 sui->allocmax = newnsegs - 1;
790 sui->allocmin = 0;
791 }
792
793 kaddr = kmap_atomic(page: header_bh->b_page);
794 header = kaddr + bh_offset(bh: header_bh);
795 header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs);
796 kunmap_atomic(kaddr);
797
798 mark_buffer_dirty(bh: header_bh);
799 nilfs_mdt_mark_dirty(inode: sufile);
800 nilfs_set_nsegments(nilfs, nsegs: newnsegs);
801
802out_header:
803 brelse(bh: header_bh);
804out:
805 up_write(sem: &NILFS_MDT(inode: sufile)->mi_sem);
806 return ret;
807}
808
809/**
810 * nilfs_sufile_get_suinfo -
811 * @sufile: inode of segment usage file
812 * @segnum: segment number to start looking
813 * @buf: array of suinfo
814 * @sisz: byte size of suinfo
815 * @nsi: size of suinfo array
816 *
817 * Description:
818 *
819 * Return Value: On success, 0 is returned and .... On error, one of the
820 * following negative error codes is returned.
821 *
822 * %-EIO - I/O error.
823 *
824 * %-ENOMEM - Insufficient amount of memory available.
825 */
826ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
827 unsigned int sisz, size_t nsi)
828{
829 struct buffer_head *su_bh;
830 struct nilfs_segment_usage *su;
831 struct nilfs_suinfo *si = buf;
832 size_t susz = NILFS_MDT(inode: sufile)->mi_entry_size;
833 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
834 void *kaddr;
835 unsigned long nsegs, segusages_per_block;
836 ssize_t n;
837 int ret, i, j;
838
839 down_read(sem: &NILFS_MDT(inode: sufile)->mi_sem);
840
841 segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
842 nsegs = min_t(unsigned long,
843 nilfs_sufile_get_nsegments(sufile) - segnum,
844 nsi);
845 for (i = 0; i < nsegs; i += n, segnum += n) {
846 n = min_t(unsigned long,
847 segusages_per_block -
848 nilfs_sufile_get_offset(sufile, segnum),
849 nsegs - i);
850 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create: 0,
851 bhp: &su_bh);
852 if (ret < 0) {
853 if (ret != -ENOENT)
854 goto out;
855 /* hole */
856 memset(si, 0, sisz * n);
857 si = (void *)si + sisz * n;
858 continue;
859 }
860
861 kaddr = kmap_atomic(page: su_bh->b_page);
862 su = nilfs_sufile_block_get_segment_usage(
863 sufile, segnum, bh: su_bh, kaddr);
864 for (j = 0; j < n;
865 j++, su = (void *)su + susz, si = (void *)si + sisz) {
866 si->sui_lastmod = le64_to_cpu(su->su_lastmod);
867 si->sui_nblocks = le32_to_cpu(su->su_nblocks);
868 si->sui_flags = le32_to_cpu(su->su_flags) &
869 ~BIT(NILFS_SEGMENT_USAGE_ACTIVE);
870 if (nilfs_segment_is_active(nilfs, n: segnum + j))
871 si->sui_flags |=
872 BIT(NILFS_SEGMENT_USAGE_ACTIVE);
873 }
874 kunmap_atomic(kaddr);
875 brelse(bh: su_bh);
876 }
877 ret = nsegs;
878
879 out:
880 up_read(sem: &NILFS_MDT(inode: sufile)->mi_sem);
881 return ret;
882}
883
884/**
885 * nilfs_sufile_set_suinfo - sets segment usage info
886 * @sufile: inode of segment usage file
887 * @buf: array of suinfo_update
888 * @supsz: byte size of suinfo_update
889 * @nsup: size of suinfo_update array
890 *
891 * Description: Takes an array of nilfs_suinfo_update structs and updates
892 * segment usage accordingly. Only the fields indicated by the sup_flags
893 * are updated.
894 *
895 * Return Value: On success, 0 is returned. On error, one of the
896 * following negative error codes is returned.
897 *
898 * %-EIO - I/O error.
899 *
900 * %-ENOMEM - Insufficient amount of memory available.
901 *
902 * %-EINVAL - Invalid values in input (segment number, flags or nblocks)
903 */
904ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf,
905 unsigned int supsz, size_t nsup)
906{
907 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
908 struct buffer_head *header_bh, *bh;
909 struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup;
910 struct nilfs_segment_usage *su;
911 void *kaddr;
912 unsigned long blkoff, prev_blkoff;
913 int cleansi, cleansu, dirtysi, dirtysu;
914 long ncleaned = 0, ndirtied = 0;
915 int ret = 0;
916
917 if (unlikely(nsup == 0))
918 return ret;
919
920 for (sup = buf; sup < supend; sup = (void *)sup + supsz) {
921 if (sup->sup_segnum >= nilfs->ns_nsegments
922 || (sup->sup_flags &
923 (~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS))
924 || (nilfs_suinfo_update_nblocks(sup) &&
925 sup->sup_sui.sui_nblocks >
926 nilfs->ns_blocks_per_segment))
927 return -EINVAL;
928 }
929
930 down_write(sem: &NILFS_MDT(inode: sufile)->mi_sem);
931
932 ret = nilfs_sufile_get_header_block(sufile, bhp: &header_bh);
933 if (ret < 0)
934 goto out_sem;
935
936 sup = buf;
937 blkoff = nilfs_sufile_get_blkoff(sufile, segnum: sup->sup_segnum);
938 ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
939 if (ret < 0)
940 goto out_header;
941
942 for (;;) {
943 kaddr = kmap_atomic(page: bh->b_page);
944 su = nilfs_sufile_block_get_segment_usage(
945 sufile, segnum: sup->sup_segnum, bh, kaddr);
946
947 if (nilfs_suinfo_update_lastmod(sup))
948 su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod);
949
950 if (nilfs_suinfo_update_nblocks(sup))
951 su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks);
952
953 if (nilfs_suinfo_update_flags(sup)) {
954 /*
955 * Active flag is a virtual flag projected by running
956 * nilfs kernel code - drop it not to write it to
957 * disk.
958 */
959 sup->sup_sui.sui_flags &=
960 ~BIT(NILFS_SEGMENT_USAGE_ACTIVE);
961
962 cleansi = nilfs_suinfo_clean(si: &sup->sup_sui);
963 cleansu = nilfs_segment_usage_clean(su);
964 dirtysi = nilfs_suinfo_dirty(si: &sup->sup_sui);
965 dirtysu = nilfs_segment_usage_dirty(su);
966
967 if (cleansi && !cleansu)
968 ++ncleaned;
969 else if (!cleansi && cleansu)
970 --ncleaned;
971
972 if (dirtysi && !dirtysu)
973 ++ndirtied;
974 else if (!dirtysi && dirtysu)
975 --ndirtied;
976
977 su->su_flags = cpu_to_le32(sup->sup_sui.sui_flags);
978 }
979
980 kunmap_atomic(kaddr);
981
982 sup = (void *)sup + supsz;
983 if (sup >= supend)
984 break;
985
986 prev_blkoff = blkoff;
987 blkoff = nilfs_sufile_get_blkoff(sufile, segnum: sup->sup_segnum);
988 if (blkoff == prev_blkoff)
989 continue;
990
991 /* get different block */
992 mark_buffer_dirty(bh);
993 put_bh(bh);
994 ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
995 if (unlikely(ret < 0))
996 goto out_mark;
997 }
998 mark_buffer_dirty(bh);
999 put_bh(bh);
1000
1001 out_mark:
1002 if (ncleaned || ndirtied) {
1003 nilfs_sufile_mod_counter(header_bh, ncleanadd: (u64)ncleaned,
1004 ndirtyadd: (u64)ndirtied);
1005 NILFS_SUI(sufile)->ncleansegs += ncleaned;
1006 }
1007 nilfs_mdt_mark_dirty(inode: sufile);
1008 out_header:
1009 put_bh(bh: header_bh);
1010 out_sem:
1011 up_write(sem: &NILFS_MDT(inode: sufile)->mi_sem);
1012 return ret;
1013}
1014
1015/**
1016 * nilfs_sufile_trim_fs() - trim ioctl handle function
1017 * @sufile: inode of segment usage file
1018 * @range: fstrim_range structure
1019 *
1020 * start: First Byte to trim
1021 * len: number of Bytes to trim from start
1022 * minlen: minimum extent length in Bytes
1023 *
1024 * Decription: nilfs_sufile_trim_fs goes through all segments containing bytes
1025 * from start to start+len. start is rounded up to the next block boundary
1026 * and start+len is rounded down. For each clean segment blkdev_issue_discard
1027 * function is invoked.
1028 *
1029 * Return Value: On success, 0 is returned or negative error code, otherwise.
1030 */
1031int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)
1032{
1033 struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
1034 struct buffer_head *su_bh;
1035 struct nilfs_segment_usage *su;
1036 void *kaddr;
1037 size_t n, i, susz = NILFS_MDT(inode: sufile)->mi_entry_size;
1038 sector_t seg_start, seg_end, start_block, end_block;
1039 sector_t start = 0, nblocks = 0;
1040 u64 segnum, segnum_end, minlen, len, max_blocks, ndiscarded = 0;
1041 int ret = 0;
1042 unsigned int sects_per_block;
1043
1044 sects_per_block = (1 << nilfs->ns_blocksize_bits) /
1045 bdev_logical_block_size(bdev: nilfs->ns_bdev);
1046 len = range->len >> nilfs->ns_blocksize_bits;
1047 minlen = range->minlen >> nilfs->ns_blocksize_bits;
1048 max_blocks = ((u64)nilfs->ns_nsegments * nilfs->ns_blocks_per_segment);
1049
1050 if (!len || range->start >= max_blocks << nilfs->ns_blocksize_bits)
1051 return -EINVAL;
1052
1053 start_block = (range->start + nilfs->ns_blocksize - 1) >>
1054 nilfs->ns_blocksize_bits;
1055
1056 /*
1057 * range->len can be very large (actually, it is set to
1058 * ULLONG_MAX by default) - truncate upper end of the range
1059 * carefully so as not to overflow.
1060 */
1061 if (max_blocks - start_block < len)
1062 end_block = max_blocks - 1;
1063 else
1064 end_block = start_block + len - 1;
1065
1066 segnum = nilfs_get_segnum_of_block(nilfs, blocknr: start_block);
1067 segnum_end = nilfs_get_segnum_of_block(nilfs, blocknr: end_block);
1068
1069 down_read(sem: &NILFS_MDT(inode: sufile)->mi_sem);
1070
1071 while (segnum <= segnum_end) {
1072 n = nilfs_sufile_segment_usages_in_block(sufile, curr: segnum,
1073 max: segnum_end);
1074
1075 ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create: 0,
1076 bhp: &su_bh);
1077 if (ret < 0) {
1078 if (ret != -ENOENT)
1079 goto out_sem;
1080 /* hole */
1081 segnum += n;
1082 continue;
1083 }
1084
1085 kaddr = kmap_atomic(page: su_bh->b_page);
1086 su = nilfs_sufile_block_get_segment_usage(sufile, segnum,
1087 bh: su_bh, kaddr);
1088 for (i = 0; i < n; ++i, ++segnum, su = (void *)su + susz) {
1089 if (!nilfs_segment_usage_clean(su))
1090 continue;
1091
1092 nilfs_get_segment_range(nilfs, segnum, seg_start: &seg_start,
1093 seg_end: &seg_end);
1094
1095 if (!nblocks) {
1096 /* start new extent */
1097 start = seg_start;
1098 nblocks = seg_end - seg_start + 1;
1099 continue;
1100 }
1101
1102 if (start + nblocks == seg_start) {
1103 /* add to previous extent */
1104 nblocks += seg_end - seg_start + 1;
1105 continue;
1106 }
1107
1108 /* discard previous extent */
1109 if (start < start_block) {
1110 nblocks -= start_block - start;
1111 start = start_block;
1112 }
1113
1114 if (nblocks >= minlen) {
1115 kunmap_atomic(kaddr);
1116
1117 ret = blkdev_issue_discard(bdev: nilfs->ns_bdev,
1118 sector: start * sects_per_block,
1119 nr_sects: nblocks * sects_per_block,
1120 GFP_NOFS);
1121 if (ret < 0) {
1122 put_bh(bh: su_bh);
1123 goto out_sem;
1124 }
1125
1126 ndiscarded += nblocks;
1127 kaddr = kmap_atomic(page: su_bh->b_page);
1128 su = nilfs_sufile_block_get_segment_usage(
1129 sufile, segnum, bh: su_bh, kaddr);
1130 }
1131
1132 /* start new extent */
1133 start = seg_start;
1134 nblocks = seg_end - seg_start + 1;
1135 }
1136 kunmap_atomic(kaddr);
1137 put_bh(bh: su_bh);
1138 }
1139
1140
1141 if (nblocks) {
1142 /* discard last extent */
1143 if (start < start_block) {
1144 nblocks -= start_block - start;
1145 start = start_block;
1146 }
1147 if (start + nblocks > end_block + 1)
1148 nblocks = end_block - start + 1;
1149
1150 if (nblocks >= minlen) {
1151 ret = blkdev_issue_discard(bdev: nilfs->ns_bdev,
1152 sector: start * sects_per_block,
1153 nr_sects: nblocks * sects_per_block,
1154 GFP_NOFS);
1155 if (!ret)
1156 ndiscarded += nblocks;
1157 }
1158 }
1159
1160out_sem:
1161 up_read(sem: &NILFS_MDT(inode: sufile)->mi_sem);
1162
1163 range->len = ndiscarded << nilfs->ns_blocksize_bits;
1164 return ret;
1165}
1166
1167/**
1168 * nilfs_sufile_read - read or get sufile inode
1169 * @sb: super block instance
1170 * @susize: size of a segment usage entry
1171 * @raw_inode: on-disk sufile inode
1172 * @inodep: buffer to store the inode
1173 */
1174int nilfs_sufile_read(struct super_block *sb, size_t susize,
1175 struct nilfs_inode *raw_inode, struct inode **inodep)
1176{
1177 struct inode *sufile;
1178 struct nilfs_sufile_info *sui;
1179 struct buffer_head *header_bh;
1180 struct nilfs_sufile_header *header;
1181 void *kaddr;
1182 int err;
1183
1184 if (susize > sb->s_blocksize) {
1185 nilfs_err(sb, "too large segment usage size: %zu bytes",
1186 susize);
1187 return -EINVAL;
1188 } else if (susize < NILFS_MIN_SEGMENT_USAGE_SIZE) {
1189 nilfs_err(sb, "too small segment usage size: %zu bytes",
1190 susize);
1191 return -EINVAL;
1192 }
1193
1194 sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO);
1195 if (unlikely(!sufile))
1196 return -ENOMEM;
1197 if (!(sufile->i_state & I_NEW))
1198 goto out;
1199
1200 err = nilfs_mdt_init(inode: sufile, NILFS_MDT_GFP, objsz: sizeof(*sui));
1201 if (err)
1202 goto failed;
1203
1204 nilfs_mdt_set_entry_size(sufile, susize,
1205 sizeof(struct nilfs_sufile_header));
1206
1207 err = nilfs_read_inode_common(sufile, raw_inode);
1208 if (err)
1209 goto failed;
1210
1211 err = nilfs_sufile_get_header_block(sufile, bhp: &header_bh);
1212 if (err)
1213 goto failed;
1214
1215 sui = NILFS_SUI(sufile);
1216 kaddr = kmap_atomic(page: header_bh->b_page);
1217 header = kaddr + bh_offset(bh: header_bh);
1218 sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs);
1219 kunmap_atomic(kaddr);
1220 brelse(bh: header_bh);
1221
1222 sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1;
1223 sui->allocmin = 0;
1224
1225 unlock_new_inode(sufile);
1226 out:
1227 *inodep = sufile;
1228 return 0;
1229 failed:
1230 iget_failed(sufile);
1231 return err;
1232}
1233

source code of linux/fs/nilfs2/sufile.c