2 * recovery.c - NILFS recovery logic
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
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.
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.
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
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
23 #include <linux/buffer_head.h>
24 #include <linux/blkdev.h>
25 #include <linux/swap.h>
26 #include <linux/slab.h>
27 #include <linux/crc32.h>
35 * Segment check result
39 NILFS_SEG_NO_SUPER_ROOT,
43 NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT,
44 NILFS_SEG_FAIL_CHECKSUM_FULL,
45 NILFS_SEG_FAIL_CONSISTENCY,
48 /* work structure for recovery */
49 struct nilfs_recovery_block {
50 ino_t ino; /* Inode number of the file that this block
52 sector_t blocknr; /* block number */
53 __u64 vblocknr; /* virtual block number */
54 unsigned long blkoff; /* File offset of the data block (per block) */
55 struct list_head list;
59 static int nilfs_warn_segment_error(int err)
62 case NILFS_SEG_FAIL_IO:
64 "NILFS warning: I/O error on loading last segment\n");
66 case NILFS_SEG_FAIL_MAGIC:
68 "NILFS warning: Segment magic number invalid\n");
70 case NILFS_SEG_FAIL_SEQ:
72 "NILFS warning: Sequence number mismatch\n");
74 case NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT:
76 "NILFS warning: Checksum error in super root\n");
78 case NILFS_SEG_FAIL_CHECKSUM_FULL:
80 "NILFS warning: Checksum error in segment payload\n");
82 case NILFS_SEG_FAIL_CONSISTENCY:
84 "NILFS warning: Inconsistent segment\n");
86 case NILFS_SEG_NO_SUPER_ROOT:
88 "NILFS warning: No super root in the last segment\n");
95 * nilfs_compute_checksum - compute checksum of blocks continuously
96 * @nilfs: nilfs object
97 * @bhs: buffer head of start block
98 * @sum: place to store result
99 * @offset: offset bytes in the first block
100 * @check_bytes: number of bytes to be checked
101 * @start: DBN of start block
102 * @nblock: number of blocks to be checked
104 static int nilfs_compute_checksum(struct the_nilfs *nilfs,
105 struct buffer_head *bhs, u32 *sum,
106 unsigned long offset, u64 check_bytes,
107 sector_t start, unsigned long nblock)
109 unsigned int blocksize = nilfs->ns_blocksize;
113 BUG_ON(offset >= blocksize);
114 check_bytes -= offset;
115 size = min_t(u64, check_bytes, blocksize - offset);
116 crc = crc32_le(nilfs->ns_crc_seed,
117 (unsigned char *)bhs->b_data + offset, size);
120 struct buffer_head *bh;
122 bh = __bread(nilfs->ns_bdev, ++start, blocksize);
126 size = min_t(u64, check_bytes, blocksize);
127 crc = crc32_le(crc, bh->b_data, size);
129 } while (--nblock > 0);
136 * nilfs_read_super_root_block - read super root block
137 * @nilfs: nilfs object
138 * @sr_block: disk block number of the super root block
139 * @pbh: address of a buffer_head pointer to return super root buffer
140 * @check: CRC check flag
142 int nilfs_read_super_root_block(struct the_nilfs *nilfs, sector_t sr_block,
143 struct buffer_head **pbh, int check)
145 struct buffer_head *bh_sr;
146 struct nilfs_super_root *sr;
151 bh_sr = __bread(nilfs->ns_bdev, sr_block, nilfs->ns_blocksize);
152 if (unlikely(!bh_sr)) {
153 ret = NILFS_SEG_FAIL_IO;
157 sr = (struct nilfs_super_root *)bh_sr->b_data;
159 unsigned bytes = le16_to_cpu(sr->sr_bytes);
161 if (bytes == 0 || bytes > nilfs->ns_blocksize) {
162 ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT;
165 if (nilfs_compute_checksum(
166 nilfs, bh_sr, &crc, sizeof(sr->sr_sum), bytes,
168 ret = NILFS_SEG_FAIL_IO;
171 if (crc != le32_to_cpu(sr->sr_sum)) {
172 ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT;
183 return nilfs_warn_segment_error(ret);
187 * nilfs_read_log_header - read summary header of the specified log
188 * @nilfs: nilfs object
189 * @start_blocknr: start block number of the log
190 * @sum: pointer to return segment summary structure
192 static struct buffer_head *
193 nilfs_read_log_header(struct the_nilfs *nilfs, sector_t start_blocknr,
194 struct nilfs_segment_summary **sum)
196 struct buffer_head *bh_sum;
198 bh_sum = __bread(nilfs->ns_bdev, start_blocknr, nilfs->ns_blocksize);
200 *sum = (struct nilfs_segment_summary *)bh_sum->b_data;
205 * nilfs_validate_log - verify consistency of log
206 * @nilfs: nilfs object
207 * @seg_seq: sequence number of segment
208 * @bh_sum: buffer head of summary block
209 * @sum: segment summary struct
211 static int nilfs_validate_log(struct the_nilfs *nilfs, u64 seg_seq,
212 struct buffer_head *bh_sum,
213 struct nilfs_segment_summary *sum)
215 unsigned long nblock;
219 ret = NILFS_SEG_FAIL_MAGIC;
220 if (le32_to_cpu(sum->ss_magic) != NILFS_SEGSUM_MAGIC)
223 ret = NILFS_SEG_FAIL_SEQ;
224 if (le64_to_cpu(sum->ss_seq) != seg_seq)
227 nblock = le32_to_cpu(sum->ss_nblocks);
228 ret = NILFS_SEG_FAIL_CONSISTENCY;
229 if (unlikely(nblock == 0 || nblock > nilfs->ns_blocks_per_segment))
230 /* This limits the number of blocks read in the CRC check */
233 ret = NILFS_SEG_FAIL_IO;
234 if (nilfs_compute_checksum(nilfs, bh_sum, &crc, sizeof(sum->ss_datasum),
235 ((u64)nblock << nilfs->ns_blocksize_bits),
236 bh_sum->b_blocknr, nblock))
239 ret = NILFS_SEG_FAIL_CHECKSUM_FULL;
240 if (crc != le32_to_cpu(sum->ss_datasum))
248 * nilfs_read_summary_info - read an item on summary blocks of a log
249 * @nilfs: nilfs object
250 * @pbh: the current buffer head on summary blocks [in, out]
251 * @offset: the current byte offset on summary blocks [in, out]
252 * @bytes: byte size of the item to be read
254 static void *nilfs_read_summary_info(struct the_nilfs *nilfs,
255 struct buffer_head **pbh,
256 unsigned int *offset, unsigned int bytes)
261 BUG_ON((*pbh)->b_size < *offset);
262 if (bytes > (*pbh)->b_size - *offset) {
263 blocknr = (*pbh)->b_blocknr;
265 *pbh = __bread(nilfs->ns_bdev, blocknr + 1,
266 nilfs->ns_blocksize);
271 ptr = (*pbh)->b_data + *offset;
277 * nilfs_skip_summary_info - skip items on summary blocks of a log
278 * @nilfs: nilfs object
279 * @pbh: the current buffer head on summary blocks [in, out]
280 * @offset: the current byte offset on summary blocks [in, out]
281 * @bytes: byte size of the item to be skipped
282 * @count: number of items to be skipped
284 static void nilfs_skip_summary_info(struct the_nilfs *nilfs,
285 struct buffer_head **pbh,
286 unsigned int *offset, unsigned int bytes,
289 unsigned int rest_item_in_current_block
290 = ((*pbh)->b_size - *offset) / bytes;
292 if (count <= rest_item_in_current_block) {
293 *offset += bytes * count;
295 sector_t blocknr = (*pbh)->b_blocknr;
296 unsigned int nitem_per_block = (*pbh)->b_size / bytes;
299 count -= rest_item_in_current_block;
300 bcnt = DIV_ROUND_UP(count, nitem_per_block);
301 *offset = bytes * (count - (bcnt - 1) * nitem_per_block);
304 *pbh = __bread(nilfs->ns_bdev, blocknr + bcnt,
305 nilfs->ns_blocksize);
310 * nilfs_scan_dsync_log - get block information of a log written for data sync
311 * @nilfs: nilfs object
312 * @start_blocknr: start block number of the log
313 * @sum: log summary information
314 * @head: list head to add nilfs_recovery_block struct
316 static int nilfs_scan_dsync_log(struct the_nilfs *nilfs, sector_t start_blocknr,
317 struct nilfs_segment_summary *sum,
318 struct list_head *head)
320 struct buffer_head *bh;
322 u32 nfinfo, sumbytes;
327 nfinfo = le32_to_cpu(sum->ss_nfinfo);
331 sumbytes = le32_to_cpu(sum->ss_sumbytes);
332 blocknr = start_blocknr + DIV_ROUND_UP(sumbytes, nilfs->ns_blocksize);
333 bh = __bread(nilfs->ns_bdev, start_blocknr, nilfs->ns_blocksize);
337 offset = le16_to_cpu(sum->ss_bytes);
339 unsigned long nblocks, ndatablk, nnodeblk;
340 struct nilfs_finfo *finfo;
342 finfo = nilfs_read_summary_info(nilfs, &bh, &offset,
344 if (unlikely(!finfo))
347 ino = le64_to_cpu(finfo->fi_ino);
348 nblocks = le32_to_cpu(finfo->fi_nblocks);
349 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
350 nnodeblk = nblocks - ndatablk;
352 while (ndatablk-- > 0) {
353 struct nilfs_recovery_block *rb;
354 struct nilfs_binfo_v *binfo;
356 binfo = nilfs_read_summary_info(nilfs, &bh, &offset,
358 if (unlikely(!binfo))
361 rb = kmalloc(sizeof(*rb), GFP_NOFS);
367 rb->blocknr = blocknr++;
368 rb->vblocknr = le64_to_cpu(binfo->bi_vblocknr);
369 rb->blkoff = le64_to_cpu(binfo->bi_blkoff);
370 /* INIT_LIST_HEAD(&rb->list); */
371 list_add_tail(&rb->list, head);
375 blocknr += nnodeblk; /* always 0 for data sync logs */
376 nilfs_skip_summary_info(nilfs, &bh, &offset, sizeof(__le64),
383 brelse(bh); /* brelse(NULL) is just ignored */
387 static void dispose_recovery_list(struct list_head *head)
389 while (!list_empty(head)) {
390 struct nilfs_recovery_block *rb
391 = list_entry(head->next,
392 struct nilfs_recovery_block, list);
398 struct nilfs_segment_entry {
399 struct list_head list;
403 static int nilfs_segment_list_add(struct list_head *head, __u64 segnum)
405 struct nilfs_segment_entry *ent = kmalloc(sizeof(*ent), GFP_NOFS);
410 ent->segnum = segnum;
411 INIT_LIST_HEAD(&ent->list);
412 list_add_tail(&ent->list, head);
416 void nilfs_dispose_segment_list(struct list_head *head)
418 while (!list_empty(head)) {
419 struct nilfs_segment_entry *ent
420 = list_entry(head->next,
421 struct nilfs_segment_entry, list);
422 list_del(&ent->list);
427 static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs,
428 struct nilfs_sb_info *sbi,
429 struct nilfs_recovery_info *ri)
431 struct list_head *head = &ri->ri_used_segments;
432 struct nilfs_segment_entry *ent, *n;
433 struct inode *sufile = nilfs->ns_sufile;
438 segnum[0] = nilfs->ns_segnum;
439 segnum[1] = nilfs->ns_nextnum;
440 segnum[2] = ri->ri_segnum;
441 segnum[3] = ri->ri_nextnum;
443 nilfs_attach_writer(nilfs, sbi);
445 * Releasing the next segment of the latest super root.
446 * The next segment is invalidated by this recovery.
448 err = nilfs_sufile_free(sufile, segnum[1]);
452 for (i = 1; i < 4; i++) {
453 err = nilfs_segment_list_add(head, segnum[i]);
459 * Collecting segments written after the latest super root.
460 * These are marked dirty to avoid being reallocated in the next write.
462 list_for_each_entry_safe(ent, n, head, list) {
463 if (ent->segnum != segnum[0]) {
464 err = nilfs_sufile_scrap(sufile, ent->segnum);
468 list_del(&ent->list);
472 /* Allocate new segments for recovery */
473 err = nilfs_sufile_alloc(sufile, &segnum[0]);
477 nilfs->ns_pseg_offset = 0;
478 nilfs->ns_seg_seq = ri->ri_seq + 2;
479 nilfs->ns_nextnum = nilfs->ns_segnum = segnum[0];
482 /* No need to recover sufile because it will be destroyed on error */
483 nilfs_detach_writer(nilfs, sbi);
487 static int nilfs_recovery_copy_block(struct the_nilfs *nilfs,
488 struct nilfs_recovery_block *rb,
491 struct buffer_head *bh_org;
494 bh_org = __bread(nilfs->ns_bdev, rb->blocknr, nilfs->ns_blocksize);
495 if (unlikely(!bh_org))
498 kaddr = kmap_atomic(page, KM_USER0);
499 memcpy(kaddr + bh_offset(bh_org), bh_org->b_data, bh_org->b_size);
500 kunmap_atomic(kaddr, KM_USER0);
505 static int nilfs_recover_dsync_blocks(struct the_nilfs *nilfs,
506 struct nilfs_sb_info *sbi,
507 struct list_head *head,
508 unsigned long *nr_salvaged_blocks)
511 struct nilfs_recovery_block *rb, *n;
512 unsigned blocksize = nilfs->ns_blocksize;
515 int err = 0, err2 = 0;
517 list_for_each_entry_safe(rb, n, head, list) {
518 inode = nilfs_iget(sbi->s_super, rb->ino);
520 err = PTR_ERR(inode);
525 pos = rb->blkoff << inode->i_blkbits;
527 err = block_write_begin(NULL, inode->i_mapping, pos, blocksize,
528 0, &page, NULL, nilfs_get_block);
532 err = nilfs_recovery_copy_block(nilfs, rb, page);
536 err = nilfs_set_file_dirty(sbi, inode, 1);
540 block_write_end(NULL, inode->i_mapping, pos, blocksize,
541 blocksize, page, NULL);
544 page_cache_release(page);
546 (*nr_salvaged_blocks)++;
551 page_cache_release(page);
555 "NILFS warning: error recovering data block "
556 "(err=%d, ino=%lu, block-offset=%llu)\n",
557 err, (unsigned long)rb->ino,
558 (unsigned long long)rb->blkoff);
562 iput(inode); /* iput(NULL) is just ignored */
563 list_del_init(&rb->list);
570 * nilfs_do_roll_forward - salvage logical segments newer than the latest
572 * @nilfs: nilfs object
573 * @sbi: nilfs_sb_info
574 * @ri: pointer to a nilfs_recovery_info
576 static int nilfs_do_roll_forward(struct the_nilfs *nilfs,
577 struct nilfs_sb_info *sbi,
578 struct nilfs_recovery_info *ri)
580 struct buffer_head *bh_sum = NULL;
581 struct nilfs_segment_summary *sum;
583 sector_t seg_start, seg_end; /* Starting/ending DBN of full segment */
584 unsigned long nsalvaged_blocks = 0;
587 __u64 segnum, nextnum = 0;
590 LIST_HEAD(dsync_blocks); /* list of data blocks to be recovered */
593 RF_DSYNC_ST, /* scanning data-sync segments */
595 int state = RF_INIT_ST;
597 nilfs_attach_writer(nilfs, sbi);
598 pseg_start = ri->ri_lsegs_start;
599 seg_seq = ri->ri_lsegs_start_seq;
600 segnum = nilfs_get_segnum_of_block(nilfs, pseg_start);
601 nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end);
603 while (segnum != ri->ri_segnum || pseg_start <= ri->ri_pseg_start) {
605 bh_sum = nilfs_read_log_header(nilfs, pseg_start, &sum);
611 ret = nilfs_validate_log(nilfs, seg_seq, bh_sum, sum);
613 if (ret == NILFS_SEG_FAIL_IO) {
620 flags = le16_to_cpu(sum->ss_flags);
621 if (flags & NILFS_SS_SR)
624 /* Found a valid partial segment; do recovery actions */
625 nextnum = nilfs_get_segnum_of_block(nilfs,
626 le64_to_cpu(sum->ss_next));
628 nilfs->ns_ctime = le64_to_cpu(sum->ss_create);
629 if (!(flags & NILFS_SS_GC))
630 nilfs->ns_nongc_ctime = nilfs->ns_ctime;
634 if (!(flags & NILFS_SS_LOGBGN) ||
635 !(flags & NILFS_SS_SYNDT))
640 if (!(flags & NILFS_SS_SYNDT))
643 err = nilfs_scan_dsync_log(nilfs, pseg_start, sum,
647 if (flags & NILFS_SS_LOGEND) {
648 err = nilfs_recover_dsync_blocks(
649 nilfs, sbi, &dsync_blocks,
655 break; /* Fall through to try_next_pseg */
659 if (pseg_start == ri->ri_lsegs_end)
661 pseg_start += le32_to_cpu(sum->ss_nblocks);
662 if (pseg_start < seg_end)
667 if (pseg_start == ri->ri_lsegs_end)
671 /* Looking to the next full segment */
676 nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end);
677 pseg_start = seg_start;
680 if (nsalvaged_blocks) {
681 printk(KERN_INFO "NILFS (device %s): salvaged %lu blocks\n",
682 sbi->s_super->s_id, nsalvaged_blocks);
683 ri->ri_need_recovery = NILFS_RECOVERY_ROLLFORWARD_DONE;
687 dispose_recovery_list(&dsync_blocks);
688 nilfs_detach_writer(nilfs, sbi);
695 "NILFS (device %s): Error roll-forwarding "
696 "(err=%d, pseg block=%llu). ",
697 sbi->s_super->s_id, err, (unsigned long long)pseg_start);
701 static void nilfs_finish_roll_forward(struct the_nilfs *nilfs,
702 struct nilfs_recovery_info *ri)
704 struct buffer_head *bh;
707 if (nilfs_get_segnum_of_block(nilfs, ri->ri_lsegs_start) !=
708 nilfs_get_segnum_of_block(nilfs, ri->ri_super_root))
711 bh = __getblk(nilfs->ns_bdev, ri->ri_lsegs_start, nilfs->ns_blocksize);
713 memset(bh->b_data, 0, bh->b_size);
714 set_buffer_dirty(bh);
715 err = sync_dirty_buffer(bh);
718 "NILFS warning: buffer sync write failed during "
719 "post-cleaning of recovery.\n");
724 * nilfs_salvage_orphan_logs - salvage logs written after the latest checkpoint
725 * @nilfs: nilfs object
726 * @sbi: nilfs_sb_info
727 * @ri: pointer to a nilfs_recovery_info struct to store search results.
729 * Return Value: On success, 0 is returned. On error, one of the following
730 * negative error code is returned.
732 * %-EINVAL - Inconsistent filesystem state.
736 * %-ENOSPC - No space left on device (only in a panic state).
738 * %-ERESTARTSYS - Interrupted.
740 * %-ENOMEM - Insufficient memory available.
742 int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs,
743 struct nilfs_sb_info *sbi,
744 struct nilfs_recovery_info *ri)
748 if (ri->ri_lsegs_start == 0 || ri->ri_lsegs_end == 0)
751 err = nilfs_attach_checkpoint(sbi, ri->ri_cno);
754 "NILFS: error loading the latest checkpoint.\n");
758 err = nilfs_do_roll_forward(nilfs, sbi, ri);
762 if (ri->ri_need_recovery == NILFS_RECOVERY_ROLLFORWARD_DONE) {
763 err = nilfs_prepare_segment_for_recovery(nilfs, sbi, ri);
765 printk(KERN_ERR "NILFS: Error preparing segments for "
770 err = nilfs_attach_segment_constructor(sbi);
774 set_nilfs_discontinued(nilfs);
775 err = nilfs_construct_segment(sbi->s_super);
776 nilfs_detach_segment_constructor(sbi);
779 printk(KERN_ERR "NILFS: Oops! recovery failed. "
784 nilfs_finish_roll_forward(nilfs, ri);
788 nilfs_detach_checkpoint(sbi);
793 * nilfs_search_super_root - search the latest valid super root
795 * @ri: pointer to a nilfs_recovery_info struct to store search results.
797 * nilfs_search_super_root() looks for the latest super-root from a partial
798 * segment pointed by the superblock. It sets up struct the_nilfs through
799 * this search. It fills nilfs_recovery_info (ri) required for recovery.
801 * Return Value: On success, 0 is returned. On error, one of the following
802 * negative error code is returned.
804 * %-EINVAL - No valid segment found
808 * %-ENOMEM - Insufficient memory available.
810 int nilfs_search_super_root(struct the_nilfs *nilfs,
811 struct nilfs_recovery_info *ri)
813 struct buffer_head *bh_sum = NULL;
814 struct nilfs_segment_summary *sum;
815 sector_t pseg_start, pseg_end, sr_pseg_start = 0;
816 sector_t seg_start, seg_end; /* range of full segment (block number) */
818 unsigned long nblocks;
821 __u64 segnum, nextnum = 0;
824 int empty_seg = 0, scan_newer = 0;
827 pseg_start = nilfs->ns_last_pseg;
828 seg_seq = nilfs->ns_last_seq;
829 cno = nilfs->ns_last_cno;
830 segnum = nilfs_get_segnum_of_block(nilfs, pseg_start);
832 /* Calculate range of segment */
833 nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end);
835 /* Read ahead segment */
838 __breadahead(nilfs->ns_bdev, b++, nilfs->ns_blocksize);
842 ret = NILFS_SEG_FAIL_IO;
843 bh_sum = nilfs_read_log_header(nilfs, pseg_start, &sum);
847 ret = nilfs_validate_log(nilfs, seg_seq, bh_sum, sum);
849 if (ret == NILFS_SEG_FAIL_IO)
854 nblocks = le32_to_cpu(sum->ss_nblocks);
855 pseg_end = pseg_start + nblocks - 1;
856 if (unlikely(pseg_end > seg_end)) {
857 ret = NILFS_SEG_FAIL_CONSISTENCY;
861 /* A valid partial segment */
862 ri->ri_pseg_start = pseg_start;
863 ri->ri_seq = seg_seq;
864 ri->ri_segnum = segnum;
865 nextnum = nilfs_get_segnum_of_block(nilfs,
866 le64_to_cpu(sum->ss_next));
867 ri->ri_nextnum = nextnum;
870 flags = le16_to_cpu(sum->ss_flags);
871 if (!(flags & NILFS_SS_SR) && !scan_newer) {
872 /* This will never happen because a superblock
873 (last_segment) always points to a pseg
874 having a super root. */
875 ret = NILFS_SEG_FAIL_CONSISTENCY;
879 if (pseg_start == seg_start) {
880 nilfs_get_segment_range(nilfs, nextnum, &b, &end);
882 __breadahead(nilfs->ns_bdev, b++,
883 nilfs->ns_blocksize);
885 if (!(flags & NILFS_SS_SR)) {
886 if (!ri->ri_lsegs_start && (flags & NILFS_SS_LOGBGN)) {
887 ri->ri_lsegs_start = pseg_start;
888 ri->ri_lsegs_start_seq = seg_seq;
890 if (flags & NILFS_SS_LOGEND)
891 ri->ri_lsegs_end = pseg_start;
895 /* A valid super root was found. */
897 ri->ri_super_root = pseg_end;
898 ri->ri_lsegs_start = ri->ri_lsegs_end = 0;
900 nilfs_dispose_segment_list(&segments);
901 sr_pseg_start = pseg_start;
902 nilfs->ns_pseg_offset = pseg_start + nblocks - seg_start;
903 nilfs->ns_seg_seq = seg_seq;
904 nilfs->ns_segnum = segnum;
905 nilfs->ns_cno = cno; /* nilfs->ns_cno = ri->ri_cno + 1 */
906 nilfs->ns_ctime = le64_to_cpu(sum->ss_create);
907 nilfs->ns_nextnum = nextnum;
910 ri->ri_need_recovery = NILFS_RECOVERY_SR_UPDATED;
912 if (nilfs->ns_mount_state & NILFS_VALID_FS)
913 goto super_root_found;
918 /* Standing on a course, or met an inconsistent state */
919 pseg_start += nblocks;
920 if (pseg_start < seg_end)
928 * This can happen if a checkpoint was written without
929 * barriers, or as a result of an I/O failure.
934 /* Looking to the next full segment */
936 goto super_root_found; /* found a valid super root */
938 ret = nilfs_segment_list_add(&segments, segnum);
944 nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end);
945 pseg_start = seg_start;
949 /* Updating pointers relating to the latest checkpoint */
951 list_splice_tail(&segments, &ri->ri_used_segments);
952 nilfs->ns_last_pseg = sr_pseg_start;
953 nilfs->ns_last_seq = nilfs->ns_seg_seq;
954 nilfs->ns_last_cno = ri->ri_cno;
959 nilfs_dispose_segment_list(&segments);
960 return (ret < 0) ? ret : nilfs_warn_segment_error(ret);