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