| /* |
| * recovery.c - NILFS recovery logic |
| * |
| * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * Written by Ryusuke Konishi <ryusuke@osrg.net> |
| */ |
| |
| #include <linux/buffer_head.h> |
| #include <linux/blkdev.h> |
| #include <linux/swap.h> |
| #include <linux/slab.h> |
| #include <linux/crc32.h> |
| #include "nilfs.h" |
| #include "segment.h" |
| #include "sufile.h" |
| #include "page.h" |
| #include "segbuf.h" |
| |
| /* |
| * Segment check result |
| */ |
| enum { |
| NILFS_SEG_VALID, |
| NILFS_SEG_NO_SUPER_ROOT, |
| NILFS_SEG_FAIL_IO, |
| NILFS_SEG_FAIL_MAGIC, |
| NILFS_SEG_FAIL_SEQ, |
| NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT, |
| NILFS_SEG_FAIL_CHECKSUM_FULL, |
| NILFS_SEG_FAIL_CONSISTENCY, |
| }; |
| |
| /* work structure for recovery */ |
| struct nilfs_recovery_block { |
| ino_t ino; /* Inode number of the file that this block |
| belongs to */ |
| sector_t blocknr; /* block number */ |
| __u64 vblocknr; /* virtual block number */ |
| unsigned long blkoff; /* File offset of the data block (per block) */ |
| struct list_head list; |
| }; |
| |
| |
| static int nilfs_warn_segment_error(int err) |
| { |
| switch (err) { |
| case NILFS_SEG_FAIL_IO: |
| printk(KERN_WARNING |
| "NILFS warning: I/O error on loading last segment\n"); |
| return -EIO; |
| case NILFS_SEG_FAIL_MAGIC: |
| printk(KERN_WARNING |
| "NILFS warning: Segment magic number invalid\n"); |
| break; |
| case NILFS_SEG_FAIL_SEQ: |
| printk(KERN_WARNING |
| "NILFS warning: Sequence number mismatch\n"); |
| break; |
| case NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT: |
| printk(KERN_WARNING |
| "NILFS warning: Checksum error in super root\n"); |
| break; |
| case NILFS_SEG_FAIL_CHECKSUM_FULL: |
| printk(KERN_WARNING |
| "NILFS warning: Checksum error in segment payload\n"); |
| break; |
| case NILFS_SEG_FAIL_CONSISTENCY: |
| printk(KERN_WARNING |
| "NILFS warning: Inconsistent segment\n"); |
| break; |
| case NILFS_SEG_NO_SUPER_ROOT: |
| printk(KERN_WARNING |
| "NILFS warning: No super root in the last segment\n"); |
| break; |
| } |
| return -EINVAL; |
| } |
| |
| /** |
| * nilfs_compute_checksum - compute checksum of blocks continuously |
| * @nilfs: nilfs object |
| * @bhs: buffer head of start block |
| * @sum: place to store result |
| * @offset: offset bytes in the first block |
| * @check_bytes: number of bytes to be checked |
| * @start: DBN of start block |
| * @nblock: number of blocks to be checked |
| */ |
| static int nilfs_compute_checksum(struct the_nilfs *nilfs, |
| struct buffer_head *bhs, u32 *sum, |
| unsigned long offset, u64 check_bytes, |
| sector_t start, unsigned long nblock) |
| { |
| unsigned int blocksize = nilfs->ns_blocksize; |
| unsigned long size; |
| u32 crc; |
| |
| BUG_ON(offset >= blocksize); |
| check_bytes -= offset; |
| size = min_t(u64, check_bytes, blocksize - offset); |
| crc = crc32_le(nilfs->ns_crc_seed, |
| (unsigned char *)bhs->b_data + offset, size); |
| if (--nblock > 0) { |
| do { |
| struct buffer_head *bh; |
| |
| bh = __bread(nilfs->ns_bdev, ++start, blocksize); |
| if (!bh) |
| return -EIO; |
| check_bytes -= size; |
| size = min_t(u64, check_bytes, blocksize); |
| crc = crc32_le(crc, bh->b_data, size); |
| brelse(bh); |
| } while (--nblock > 0); |
| } |
| *sum = crc; |
| return 0; |
| } |
| |
| /** |
| * nilfs_read_super_root_block - read super root block |
| * @nilfs: nilfs object |
| * @sr_block: disk block number of the super root block |
| * @pbh: address of a buffer_head pointer to return super root buffer |
| * @check: CRC check flag |
| */ |
| int nilfs_read_super_root_block(struct the_nilfs *nilfs, sector_t sr_block, |
| struct buffer_head **pbh, int check) |
| { |
| struct buffer_head *bh_sr; |
| struct nilfs_super_root *sr; |
| u32 crc; |
| int ret; |
| |
| *pbh = NULL; |
| bh_sr = __bread(nilfs->ns_bdev, sr_block, nilfs->ns_blocksize); |
| if (unlikely(!bh_sr)) { |
| ret = NILFS_SEG_FAIL_IO; |
| goto failed; |
| } |
| |
| sr = (struct nilfs_super_root *)bh_sr->b_data; |
| if (check) { |
| unsigned bytes = le16_to_cpu(sr->sr_bytes); |
| |
| if (bytes == 0 || bytes > nilfs->ns_blocksize) { |
| ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT; |
| goto failed_bh; |
| } |
| if (nilfs_compute_checksum( |
| nilfs, bh_sr, &crc, sizeof(sr->sr_sum), bytes, |
| sr_block, 1)) { |
| ret = NILFS_SEG_FAIL_IO; |
| goto failed_bh; |
| } |
| if (crc != le32_to_cpu(sr->sr_sum)) { |
| ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT; |
| goto failed_bh; |
| } |
| } |
| *pbh = bh_sr; |
| return 0; |
| |
| failed_bh: |
| brelse(bh_sr); |
| |
| failed: |
| return nilfs_warn_segment_error(ret); |
| } |
| |
| /** |
| * nilfs_read_log_header - read summary header of the specified log |
| * @nilfs: nilfs object |
| * @start_blocknr: start block number of the log |
| * @sum: pointer to return segment summary structure |
| */ |
| static struct buffer_head * |
| nilfs_read_log_header(struct the_nilfs *nilfs, sector_t start_blocknr, |
| struct nilfs_segment_summary **sum) |
| { |
| struct buffer_head *bh_sum; |
| |
| bh_sum = __bread(nilfs->ns_bdev, start_blocknr, nilfs->ns_blocksize); |
| if (bh_sum) |
| *sum = (struct nilfs_segment_summary *)bh_sum->b_data; |
| return bh_sum; |
| } |
| |
| /** |
| * nilfs_validate_log - verify consistency of log |
| * @nilfs: nilfs object |
| * @seg_seq: sequence number of segment |
| * @bh_sum: buffer head of summary block |
| * @sum: segment summary struct |
| */ |
| static int nilfs_validate_log(struct the_nilfs *nilfs, u64 seg_seq, |
| struct buffer_head *bh_sum, |
| struct nilfs_segment_summary *sum) |
| { |
| unsigned long nblock; |
| u32 crc; |
| int ret; |
| |
| ret = NILFS_SEG_FAIL_MAGIC; |
| if (le32_to_cpu(sum->ss_magic) != NILFS_SEGSUM_MAGIC) |
| goto out; |
| |
| ret = NILFS_SEG_FAIL_SEQ; |
| if (le64_to_cpu(sum->ss_seq) != seg_seq) |
| goto out; |
| |
| nblock = le32_to_cpu(sum->ss_nblocks); |
| ret = NILFS_SEG_FAIL_CONSISTENCY; |
| if (unlikely(nblock == 0 || nblock > nilfs->ns_blocks_per_segment)) |
| /* This limits the number of blocks read in the CRC check */ |
| goto out; |
| |
| ret = NILFS_SEG_FAIL_IO; |
| if (nilfs_compute_checksum(nilfs, bh_sum, &crc, sizeof(sum->ss_datasum), |
| ((u64)nblock << nilfs->ns_blocksize_bits), |
| bh_sum->b_blocknr, nblock)) |
| goto out; |
| |
| ret = NILFS_SEG_FAIL_CHECKSUM_FULL; |
| if (crc != le32_to_cpu(sum->ss_datasum)) |
| goto out; |
| ret = 0; |
| out: |
| return ret; |
| } |
| |
| /** |
| * nilfs_read_summary_info - read an item on summary blocks of a log |
| * @nilfs: nilfs object |
| * @pbh: the current buffer head on summary blocks [in, out] |
| * @offset: the current byte offset on summary blocks [in, out] |
| * @bytes: byte size of the item to be read |
| */ |
| static void *nilfs_read_summary_info(struct the_nilfs *nilfs, |
| struct buffer_head **pbh, |
| unsigned int *offset, unsigned int bytes) |
| { |
| void *ptr; |
| sector_t blocknr; |
| |
| BUG_ON((*pbh)->b_size < *offset); |
| if (bytes > (*pbh)->b_size - *offset) { |
| blocknr = (*pbh)->b_blocknr; |
| brelse(*pbh); |
| *pbh = __bread(nilfs->ns_bdev, blocknr + 1, |
| nilfs->ns_blocksize); |
| if (unlikely(!*pbh)) |
| return NULL; |
| *offset = 0; |
| } |
| ptr = (*pbh)->b_data + *offset; |
| *offset += bytes; |
| return ptr; |
| } |
| |
| /** |
| * nilfs_skip_summary_info - skip items on summary blocks of a log |
| * @nilfs: nilfs object |
| * @pbh: the current buffer head on summary blocks [in, out] |
| * @offset: the current byte offset on summary blocks [in, out] |
| * @bytes: byte size of the item to be skipped |
| * @count: number of items to be skipped |
| */ |
| static void nilfs_skip_summary_info(struct the_nilfs *nilfs, |
| struct buffer_head **pbh, |
| unsigned int *offset, unsigned int bytes, |
| unsigned long count) |
| { |
| unsigned int rest_item_in_current_block |
| = ((*pbh)->b_size - *offset) / bytes; |
| |
| if (count <= rest_item_in_current_block) { |
| *offset += bytes * count; |
| } else { |
| sector_t blocknr = (*pbh)->b_blocknr; |
| unsigned int nitem_per_block = (*pbh)->b_size / bytes; |
| unsigned int bcnt; |
| |
| count -= rest_item_in_current_block; |
| bcnt = DIV_ROUND_UP(count, nitem_per_block); |
| *offset = bytes * (count - (bcnt - 1) * nitem_per_block); |
| |
| brelse(*pbh); |
| *pbh = __bread(nilfs->ns_bdev, blocknr + bcnt, |
| nilfs->ns_blocksize); |
| } |
| } |
| |
| /** |
| * nilfs_scan_dsync_log - get block information of a log written for data sync |
| * @nilfs: nilfs object |
| * @start_blocknr: start block number of the log |
| * @sum: log summary information |
| * @head: list head to add nilfs_recovery_block struct |
| */ |
| static int nilfs_scan_dsync_log(struct the_nilfs *nilfs, sector_t start_blocknr, |
| struct nilfs_segment_summary *sum, |
| struct list_head *head) |
| { |
| struct buffer_head *bh; |
| unsigned int offset; |
| u32 nfinfo, sumbytes; |
| sector_t blocknr; |
| ino_t ino; |
| int err = -EIO; |
| |
| nfinfo = le32_to_cpu(sum->ss_nfinfo); |
| if (!nfinfo) |
| return 0; |
| |
| sumbytes = le32_to_cpu(sum->ss_sumbytes); |
| blocknr = start_blocknr + DIV_ROUND_UP(sumbytes, nilfs->ns_blocksize); |
| bh = __bread(nilfs->ns_bdev, start_blocknr, nilfs->ns_blocksize); |
| if (unlikely(!bh)) |
| goto out; |
| |
| offset = le16_to_cpu(sum->ss_bytes); |
| for (;;) { |
| unsigned long nblocks, ndatablk, nnodeblk; |
| struct nilfs_finfo *finfo; |
| |
| finfo = nilfs_read_summary_info(nilfs, &bh, &offset, |
| sizeof(*finfo)); |
| if (unlikely(!finfo)) |
| goto out; |
| |
| ino = le64_to_cpu(finfo->fi_ino); |
| nblocks = le32_to_cpu(finfo->fi_nblocks); |
| ndatablk = le32_to_cpu(finfo->fi_ndatablk); |
| nnodeblk = nblocks - ndatablk; |
| |
| while (ndatablk-- > 0) { |
| struct nilfs_recovery_block *rb; |
| struct nilfs_binfo_v *binfo; |
| |
| binfo = nilfs_read_summary_info(nilfs, &bh, &offset, |
| sizeof(*binfo)); |
| if (unlikely(!binfo)) |
| goto out; |
| |
| rb = kmalloc(sizeof(*rb), GFP_NOFS); |
| if (unlikely(!rb)) { |
| err = -ENOMEM; |
| goto out; |
| } |
| rb->ino = ino; |
| rb->blocknr = blocknr++; |
| rb->vblocknr = le64_to_cpu(binfo->bi_vblocknr); |
| rb->blkoff = le64_to_cpu(binfo->bi_blkoff); |
| /* INIT_LIST_HEAD(&rb->list); */ |
| list_add_tail(&rb->list, head); |
| } |
| if (--nfinfo == 0) |
| break; |
| blocknr += nnodeblk; /* always 0 for data sync logs */ |
| nilfs_skip_summary_info(nilfs, &bh, &offset, sizeof(__le64), |
| nnodeblk); |
| if (unlikely(!bh)) |
| goto out; |
| } |
| err = 0; |
| out: |
| brelse(bh); /* brelse(NULL) is just ignored */ |
| return err; |
| } |
| |
| static void dispose_recovery_list(struct list_head *head) |
| { |
| while (!list_empty(head)) { |
| struct nilfs_recovery_block *rb; |
| |
| rb = list_first_entry(head, struct nilfs_recovery_block, list); |
| list_del(&rb->list); |
| kfree(rb); |
| } |
| } |
| |
| struct nilfs_segment_entry { |
| struct list_head list; |
| __u64 segnum; |
| }; |
| |
| static int nilfs_segment_list_add(struct list_head *head, __u64 segnum) |
| { |
| struct nilfs_segment_entry *ent = kmalloc(sizeof(*ent), GFP_NOFS); |
| |
| if (unlikely(!ent)) |
| return -ENOMEM; |
| |
| ent->segnum = segnum; |
| INIT_LIST_HEAD(&ent->list); |
| list_add_tail(&ent->list, head); |
| return 0; |
| } |
| |
| void nilfs_dispose_segment_list(struct list_head *head) |
| { |
| while (!list_empty(head)) { |
| struct nilfs_segment_entry *ent; |
| |
| ent = list_first_entry(head, struct nilfs_segment_entry, list); |
| list_del(&ent->list); |
| kfree(ent); |
| } |
| } |
| |
| static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs, |
| struct super_block *sb, |
| struct nilfs_recovery_info *ri) |
| { |
| struct list_head *head = &ri->ri_used_segments; |
| struct nilfs_segment_entry *ent, *n; |
| struct inode *sufile = nilfs->ns_sufile; |
| __u64 segnum[4]; |
| int err; |
| int i; |
| |
| segnum[0] = nilfs->ns_segnum; |
| segnum[1] = nilfs->ns_nextnum; |
| segnum[2] = ri->ri_segnum; |
| segnum[3] = ri->ri_nextnum; |
| |
| /* |
| * Releasing the next segment of the latest super root. |
| * The next segment is invalidated by this recovery. |
| */ |
| err = nilfs_sufile_free(sufile, segnum[1]); |
| if (unlikely(err)) |
| goto failed; |
| |
| for (i = 1; i < 4; i++) { |
| err = nilfs_segment_list_add(head, segnum[i]); |
| if (unlikely(err)) |
| goto failed; |
| } |
| |
| /* |
| * Collecting segments written after the latest super root. |
| * These are marked dirty to avoid being reallocated in the next write. |
| */ |
| list_for_each_entry_safe(ent, n, head, list) { |
| if (ent->segnum != segnum[0]) { |
| err = nilfs_sufile_scrap(sufile, ent->segnum); |
| if (unlikely(err)) |
| goto failed; |
| } |
| list_del(&ent->list); |
| kfree(ent); |
| } |
| |
| /* Allocate new segments for recovery */ |
| err = nilfs_sufile_alloc(sufile, &segnum[0]); |
| if (unlikely(err)) |
| goto failed; |
| |
| nilfs->ns_pseg_offset = 0; |
| nilfs->ns_seg_seq = ri->ri_seq + 2; |
| nilfs->ns_nextnum = nilfs->ns_segnum = segnum[0]; |
| |
| failed: |
| /* No need to recover sufile because it will be destroyed on error */ |
| return err; |
| } |
| |
| static int nilfs_recovery_copy_block(struct the_nilfs *nilfs, |
| struct nilfs_recovery_block *rb, |
| struct page *page) |
| { |
| struct buffer_head *bh_org; |
| void *kaddr; |
| |
| bh_org = __bread(nilfs->ns_bdev, rb->blocknr, nilfs->ns_blocksize); |
| if (unlikely(!bh_org)) |
| return -EIO; |
| |
| kaddr = kmap_atomic(page); |
| memcpy(kaddr + bh_offset(bh_org), bh_org->b_data, bh_org->b_size); |
| kunmap_atomic(kaddr); |
| brelse(bh_org); |
| return 0; |
| } |
| |
| static int nilfs_recover_dsync_blocks(struct the_nilfs *nilfs, |
| struct super_block *sb, |
| struct nilfs_root *root, |
| struct list_head *head, |
| unsigned long *nr_salvaged_blocks) |
| { |
| struct inode *inode; |
| struct nilfs_recovery_block *rb, *n; |
| unsigned blocksize = nilfs->ns_blocksize; |
| struct page *page; |
| loff_t pos; |
| int err = 0, err2 = 0; |
| |
| list_for_each_entry_safe(rb, n, head, list) { |
| inode = nilfs_iget(sb, root, rb->ino); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| inode = NULL; |
| goto failed_inode; |
| } |
| |
| pos = rb->blkoff << inode->i_blkbits; |
| err = block_write_begin(inode->i_mapping, pos, blocksize, |
| 0, &page, nilfs_get_block); |
| if (unlikely(err)) { |
| loff_t isize = inode->i_size; |
| if (pos + blocksize > isize) |
| nilfs_write_failed(inode->i_mapping, |
| pos + blocksize); |
| goto failed_inode; |
| } |
| |
| err = nilfs_recovery_copy_block(nilfs, rb, page); |
| if (unlikely(err)) |
| goto failed_page; |
| |
| err = nilfs_set_file_dirty(inode, 1); |
| if (unlikely(err)) |
| goto failed_page; |
| |
| block_write_end(NULL, inode->i_mapping, pos, blocksize, |
| blocksize, page, NULL); |
| |
| unlock_page(page); |
| put_page(page); |
| |
| (*nr_salvaged_blocks)++; |
| goto next; |
| |
| failed_page: |
| unlock_page(page); |
| put_page(page); |
| |
| failed_inode: |
| printk(KERN_WARNING |
| "NILFS warning: error recovering data block " |
| "(err=%d, ino=%lu, block-offset=%llu)\n", |
| err, (unsigned long)rb->ino, |
| (unsigned long long)rb->blkoff); |
| if (!err2) |
| err2 = err; |
| next: |
| iput(inode); /* iput(NULL) is just ignored */ |
| list_del_init(&rb->list); |
| kfree(rb); |
| } |
| return err2; |
| } |
| |
| /** |
| * nilfs_do_roll_forward - salvage logical segments newer than the latest |
| * checkpoint |
| * @nilfs: nilfs object |
| * @sb: super block instance |
| * @ri: pointer to a nilfs_recovery_info |
| */ |
| static int nilfs_do_roll_forward(struct the_nilfs *nilfs, |
| struct super_block *sb, |
| struct nilfs_root *root, |
| struct nilfs_recovery_info *ri) |
| { |
| struct buffer_head *bh_sum = NULL; |
| struct nilfs_segment_summary *sum = NULL; |
| sector_t pseg_start; |
| sector_t seg_start, seg_end; /* Starting/ending DBN of full segment */ |
| unsigned long nsalvaged_blocks = 0; |
| unsigned int flags; |
| u64 seg_seq; |
| __u64 segnum, nextnum = 0; |
| int empty_seg = 0; |
| int err = 0, ret; |
| LIST_HEAD(dsync_blocks); /* list of data blocks to be recovered */ |
| enum { |
| RF_INIT_ST, |
| RF_DSYNC_ST, /* scanning data-sync segments */ |
| }; |
| int state = RF_INIT_ST; |
| |
| pseg_start = ri->ri_lsegs_start; |
| seg_seq = ri->ri_lsegs_start_seq; |
| segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); |
| nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); |
| |
| while (segnum != ri->ri_segnum || pseg_start <= ri->ri_pseg_start) { |
| brelse(bh_sum); |
| bh_sum = nilfs_read_log_header(nilfs, pseg_start, &sum); |
| if (!bh_sum) { |
| err = -EIO; |
| goto failed; |
| } |
| |
| ret = nilfs_validate_log(nilfs, seg_seq, bh_sum, sum); |
| if (ret) { |
| if (ret == NILFS_SEG_FAIL_IO) { |
| err = -EIO; |
| goto failed; |
| } |
| goto strayed; |
| } |
| |
| flags = le16_to_cpu(sum->ss_flags); |
| if (flags & NILFS_SS_SR) |
| goto confused; |
| |
| /* Found a valid partial segment; do recovery actions */ |
| nextnum = nilfs_get_segnum_of_block(nilfs, |
| le64_to_cpu(sum->ss_next)); |
| empty_seg = 0; |
| nilfs->ns_ctime = le64_to_cpu(sum->ss_create); |
| if (!(flags & NILFS_SS_GC)) |
| nilfs->ns_nongc_ctime = nilfs->ns_ctime; |
| |
| switch (state) { |
| case RF_INIT_ST: |
| if (!(flags & NILFS_SS_LOGBGN) || |
| !(flags & NILFS_SS_SYNDT)) |
| goto try_next_pseg; |
| state = RF_DSYNC_ST; |
| /* Fall through */ |
| case RF_DSYNC_ST: |
| if (!(flags & NILFS_SS_SYNDT)) |
| goto confused; |
| |
| err = nilfs_scan_dsync_log(nilfs, pseg_start, sum, |
| &dsync_blocks); |
| if (unlikely(err)) |
| goto failed; |
| if (flags & NILFS_SS_LOGEND) { |
| err = nilfs_recover_dsync_blocks( |
| nilfs, sb, root, &dsync_blocks, |
| &nsalvaged_blocks); |
| if (unlikely(err)) |
| goto failed; |
| state = RF_INIT_ST; |
| } |
| break; /* Fall through to try_next_pseg */ |
| } |
| |
| try_next_pseg: |
| if (pseg_start == ri->ri_lsegs_end) |
| break; |
| pseg_start += le32_to_cpu(sum->ss_nblocks); |
| if (pseg_start < seg_end) |
| continue; |
| goto feed_segment; |
| |
| strayed: |
| if (pseg_start == ri->ri_lsegs_end) |
| break; |
| |
| feed_segment: |
| /* Looking to the next full segment */ |
| if (empty_seg++) |
| break; |
| seg_seq++; |
| segnum = nextnum; |
| nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); |
| pseg_start = seg_start; |
| } |
| |
| if (nsalvaged_blocks) { |
| printk(KERN_INFO "NILFS (device %s): salvaged %lu blocks\n", |
| sb->s_id, nsalvaged_blocks); |
| ri->ri_need_recovery = NILFS_RECOVERY_ROLLFORWARD_DONE; |
| } |
| out: |
| brelse(bh_sum); |
| dispose_recovery_list(&dsync_blocks); |
| return err; |
| |
| confused: |
| err = -EINVAL; |
| failed: |
| printk(KERN_ERR |
| "NILFS (device %s): Error roll-forwarding " |
| "(err=%d, pseg block=%llu). ", |
| sb->s_id, err, (unsigned long long)pseg_start); |
| goto out; |
| } |
| |
| static void nilfs_finish_roll_forward(struct the_nilfs *nilfs, |
| struct nilfs_recovery_info *ri) |
| { |
| struct buffer_head *bh; |
| int err; |
| |
| if (nilfs_get_segnum_of_block(nilfs, ri->ri_lsegs_start) != |
| nilfs_get_segnum_of_block(nilfs, ri->ri_super_root)) |
| return; |
| |
| bh = __getblk(nilfs->ns_bdev, ri->ri_lsegs_start, nilfs->ns_blocksize); |
| BUG_ON(!bh); |
| memset(bh->b_data, 0, bh->b_size); |
| set_buffer_dirty(bh); |
| err = sync_dirty_buffer(bh); |
| if (unlikely(err)) |
| printk(KERN_WARNING |
| "NILFS warning: buffer sync write failed during " |
| "post-cleaning of recovery.\n"); |
| brelse(bh); |
| } |
| |
| /** |
| * nilfs_salvage_orphan_logs - salvage logs written after the latest checkpoint |
| * @nilfs: nilfs object |
| * @sb: super block instance |
| * @ri: pointer to a nilfs_recovery_info struct to store search results. |
| * |
| * Return Value: On success, 0 is returned. On error, one of the following |
| * negative error code is returned. |
| * |
| * %-EINVAL - Inconsistent filesystem state. |
| * |
| * %-EIO - I/O error |
| * |
| * %-ENOSPC - No space left on device (only in a panic state). |
| * |
| * %-ERESTARTSYS - Interrupted. |
| * |
| * %-ENOMEM - Insufficient memory available. |
| */ |
| int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs, |
| struct super_block *sb, |
| struct nilfs_recovery_info *ri) |
| { |
| struct nilfs_root *root; |
| int err; |
| |
| if (ri->ri_lsegs_start == 0 || ri->ri_lsegs_end == 0) |
| return 0; |
| |
| err = nilfs_attach_checkpoint(sb, ri->ri_cno, true, &root); |
| if (unlikely(err)) { |
| printk(KERN_ERR |
| "NILFS: error loading the latest checkpoint.\n"); |
| return err; |
| } |
| |
| err = nilfs_do_roll_forward(nilfs, sb, root, ri); |
| if (unlikely(err)) |
| goto failed; |
| |
| if (ri->ri_need_recovery == NILFS_RECOVERY_ROLLFORWARD_DONE) { |
| err = nilfs_prepare_segment_for_recovery(nilfs, sb, ri); |
| if (unlikely(err)) { |
| printk(KERN_ERR "NILFS: Error preparing segments for " |
| "recovery.\n"); |
| goto failed; |
| } |
| |
| err = nilfs_attach_log_writer(sb, root); |
| if (unlikely(err)) |
| goto failed; |
| |
| set_nilfs_discontinued(nilfs); |
| err = nilfs_construct_segment(sb); |
| nilfs_detach_log_writer(sb); |
| |
| if (unlikely(err)) { |
| printk(KERN_ERR "NILFS: Oops! recovery failed. " |
| "(err=%d)\n", err); |
| goto failed; |
| } |
| |
| nilfs_finish_roll_forward(nilfs, ri); |
| } |
| |
| failed: |
| nilfs_put_root(root); |
| return err; |
| } |
| |
| /** |
| * nilfs_search_super_root - search the latest valid super root |
| * @nilfs: the_nilfs |
| * @ri: pointer to a nilfs_recovery_info struct to store search results. |
| * |
| * nilfs_search_super_root() looks for the latest super-root from a partial |
| * segment pointed by the superblock. It sets up struct the_nilfs through |
| * this search. It fills nilfs_recovery_info (ri) required for recovery. |
| * |
| * Return Value: On success, 0 is returned. On error, one of the following |
| * negative error code is returned. |
| * |
| * %-EINVAL - No valid segment found |
| * |
| * %-EIO - I/O error |
| * |
| * %-ENOMEM - Insufficient memory available. |
| */ |
| int nilfs_search_super_root(struct the_nilfs *nilfs, |
| struct nilfs_recovery_info *ri) |
| { |
| struct buffer_head *bh_sum = NULL; |
| struct nilfs_segment_summary *sum = NULL; |
| sector_t pseg_start, pseg_end, sr_pseg_start = 0; |
| sector_t seg_start, seg_end; /* range of full segment (block number) */ |
| sector_t b, end; |
| unsigned long nblocks; |
| unsigned int flags; |
| u64 seg_seq; |
| __u64 segnum, nextnum = 0; |
| __u64 cno; |
| LIST_HEAD(segments); |
| int empty_seg = 0, scan_newer = 0; |
| int ret; |
| |
| pseg_start = nilfs->ns_last_pseg; |
| seg_seq = nilfs->ns_last_seq; |
| cno = nilfs->ns_last_cno; |
| segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); |
| |
| /* Calculate range of segment */ |
| nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); |
| |
| /* Read ahead segment */ |
| b = seg_start; |
| while (b <= seg_end) |
| __breadahead(nilfs->ns_bdev, b++, nilfs->ns_blocksize); |
| |
| for (;;) { |
| brelse(bh_sum); |
| ret = NILFS_SEG_FAIL_IO; |
| bh_sum = nilfs_read_log_header(nilfs, pseg_start, &sum); |
| if (!bh_sum) |
| goto failed; |
| |
| ret = nilfs_validate_log(nilfs, seg_seq, bh_sum, sum); |
| if (ret) { |
| if (ret == NILFS_SEG_FAIL_IO) |
| goto failed; |
| goto strayed; |
| } |
| |
| nblocks = le32_to_cpu(sum->ss_nblocks); |
| pseg_end = pseg_start + nblocks - 1; |
| if (unlikely(pseg_end > seg_end)) { |
| ret = NILFS_SEG_FAIL_CONSISTENCY; |
| goto strayed; |
| } |
| |
| /* A valid partial segment */ |
| ri->ri_pseg_start = pseg_start; |
| ri->ri_seq = seg_seq; |
| ri->ri_segnum = segnum; |
| nextnum = nilfs_get_segnum_of_block(nilfs, |
| le64_to_cpu(sum->ss_next)); |
| ri->ri_nextnum = nextnum; |
| empty_seg = 0; |
| |
| flags = le16_to_cpu(sum->ss_flags); |
| if (!(flags & NILFS_SS_SR) && !scan_newer) { |
| /* This will never happen because a superblock |
| (last_segment) always points to a pseg |
| having a super root. */ |
| ret = NILFS_SEG_FAIL_CONSISTENCY; |
| goto failed; |
| } |
| |
| if (pseg_start == seg_start) { |
| nilfs_get_segment_range(nilfs, nextnum, &b, &end); |
| while (b <= end) |
| __breadahead(nilfs->ns_bdev, b++, |
| nilfs->ns_blocksize); |
| } |
| if (!(flags & NILFS_SS_SR)) { |
| if (!ri->ri_lsegs_start && (flags & NILFS_SS_LOGBGN)) { |
| ri->ri_lsegs_start = pseg_start; |
| ri->ri_lsegs_start_seq = seg_seq; |
| } |
| if (flags & NILFS_SS_LOGEND) |
| ri->ri_lsegs_end = pseg_start; |
| goto try_next_pseg; |
| } |
| |
| /* A valid super root was found. */ |
| ri->ri_cno = cno++; |
| ri->ri_super_root = pseg_end; |
| ri->ri_lsegs_start = ri->ri_lsegs_end = 0; |
| |
| nilfs_dispose_segment_list(&segments); |
| sr_pseg_start = pseg_start; |
| nilfs->ns_pseg_offset = pseg_start + nblocks - seg_start; |
| nilfs->ns_seg_seq = seg_seq; |
| nilfs->ns_segnum = segnum; |
| nilfs->ns_cno = cno; /* nilfs->ns_cno = ri->ri_cno + 1 */ |
| nilfs->ns_ctime = le64_to_cpu(sum->ss_create); |
| nilfs->ns_nextnum = nextnum; |
| |
| if (scan_newer) |
| ri->ri_need_recovery = NILFS_RECOVERY_SR_UPDATED; |
| else { |
| if (nilfs->ns_mount_state & NILFS_VALID_FS) |
| goto super_root_found; |
| scan_newer = 1; |
| } |
| |
| try_next_pseg: |
| /* Standing on a course, or met an inconsistent state */ |
| pseg_start += nblocks; |
| if (pseg_start < seg_end) |
| continue; |
| goto feed_segment; |
| |
| strayed: |
| /* Off the trail */ |
| if (!scan_newer) |
| /* |
| * This can happen if a checkpoint was written without |
| * barriers, or as a result of an I/O failure. |
| */ |
| goto failed; |
| |
| feed_segment: |
| /* Looking to the next full segment */ |
| if (empty_seg++) |
| goto super_root_found; /* found a valid super root */ |
| |
| ret = nilfs_segment_list_add(&segments, segnum); |
| if (unlikely(ret)) |
| goto failed; |
| |
| seg_seq++; |
| segnum = nextnum; |
| nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); |
| pseg_start = seg_start; |
| } |
| |
| super_root_found: |
| /* Updating pointers relating to the latest checkpoint */ |
| brelse(bh_sum); |
| list_splice_tail(&segments, &ri->ri_used_segments); |
| nilfs->ns_last_pseg = sr_pseg_start; |
| nilfs->ns_last_seq = nilfs->ns_seg_seq; |
| nilfs->ns_last_cno = ri->ri_cno; |
| return 0; |
| |
| failed: |
| brelse(bh_sum); |
| nilfs_dispose_segment_list(&segments); |
| return (ret < 0) ? ret : nilfs_warn_segment_error(ret); |
| } |