diff options
| -rw-r--r-- | Documentation/device-mapper/dm-integrity.txt | 5 | ||||
| -rw-r--r-- | drivers/md/dm-integrity.c | 40 |
2 files changed, 32 insertions, 13 deletions
diff --git a/Documentation/device-mapper/dm-integrity.txt b/Documentation/device-mapper/dm-integrity.txt index 2406f56501dc..9d9089f74206 100644 --- a/Documentation/device-mapper/dm-integrity.txt +++ b/Documentation/device-mapper/dm-integrity.txt @@ -59,6 +59,11 @@ Target arguments: either both data and tag or none of them are written. The journaled mode degrades write throughput twice because the data have to be written twice. + R - recovery mode - in this mode, journal is not replayed, + checksums are not checked and writes to the device are not + allowed. This mode is useful for data recovery if the + device cannot be activated in any of the other standard + modes. 5. the number of additional arguments diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index ecb0b592f5a0..e26a079b41ea 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -1216,6 +1216,9 @@ static void integrity_metadata(struct work_struct *w) unsigned sectors_to_process = dio->range.n_sectors; sector_t sector = dio->range.logical_sector; + if (unlikely(ic->mode == 'R')) + goto skip_io; + checksums = kmalloc((PAGE_SIZE >> SECTOR_SHIFT) * ic->tag_size + extra_space, GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN); if (!checksums) @@ -1288,6 +1291,7 @@ again: } } } +skip_io: dec_in_flight(dio); return; error: @@ -1327,6 +1331,9 @@ static int dm_integrity_map(struct dm_target *ti, struct bio *bio) return -EIO; } + if (unlikely(ic->mode == 'R') && unlikely(dio->write)) + return -EIO; + get_area_and_offset(ic, dio->range.logical_sector, &area, &offset); dio->metadata_block = get_metadata_sector_and_offset(ic, area, offset, &dio->metadata_offset); bio->bi_iter.bi_sector = get_data_sector(ic, area, offset); @@ -1926,6 +1933,9 @@ static void replay_journal(struct dm_integrity_c *ic) bool journal_empty; unsigned char unused, last_used, want_commit_seq; + if (ic->mode == 'R') + return; + if (ic->journal_uptodate) return; @@ -2705,7 +2715,7 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) } } - if (!strcmp(argv[3], "J") || !strcmp(argv[3], "D")) + if (!strcmp(argv[3], "J") || !strcmp(argv[3], "D") || !strcmp(argv[3], "R")) ic->mode = argv[3][0]; else { ti->error = "Invalid mode (expecting J or D)"; @@ -2864,14 +2874,15 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) ti->error = "Error reading superblock"; goto bad; } - if (!memcmp(ic->sb->magic, SB_MAGIC, 8)) { - should_write_sb = false; - } else { - for (i = 0; i < 512; i += 8) { - if (*(__u64 *)((__u8 *)ic->sb + i)) { - r = -EINVAL; - ti->error = "The device is not initialized"; - goto bad; + should_write_sb = false; + if (memcmp(ic->sb->magic, SB_MAGIC, 8)) { + if (ic->mode != 'R') { + for (i = 0; i < 512; i += 8) { + if (*(__u64 *)((__u8 *)ic->sb + i)) { + r = -EINVAL; + ti->error = "The device is not initialized"; + goto bad; + } } } @@ -2880,7 +2891,8 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) ti->error = "Could not initialize superblock"; goto bad; } - should_write_sb = true; + if (ic->mode != 'R') + should_write_sb = true; } if (ic->sb->version != SB_VERSION) { @@ -2954,9 +2966,11 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) } dm_bufio_set_sector_offset(ic->bufio, ic->start + ic->initial_sectors); - r = create_journal(ic, &ti->error); - if (r) - goto bad; + if (ic->mode != 'R') { + r = create_journal(ic, &ti->error); + if (r) + goto bad; + } if (should_write_sb) { int r; |