| Message ID | 1490382815-25248-1-git-send-email-bo.li.liu@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Mar 24, 2017 at 12:13:35PM -0700, Liu Bo wrote: > Now that scrub can fix data errors with the help of parity for raid56 > profile, repair during read is able to as well. > > Although the mirror num in raid56 senario has different meanings, i.e. (typo: scenario) > 0 or 1: read data directly > > 1: do recover with parity, > it could be fit into how we repair bad block during read. Could we possibly add some symbolic names for the RAID56 case? > > The trick is to use BTRFS_MAP_READ instead of BTRFS_MAP_WRITE to get the > device and position on it. Please also document the trick in the code before the following. > + if (btrfs_is_parity_mirror(map_tree, logical, length, mirror_num)) { > + /* use BTRFS_MAP_READ to get the phy dev and sector */ > + ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, logical, > + &map_length, &bbio, 0); > + if (ret) { > + btrfs_bio_counter_dec(fs_info); > + bio_put(bio); > + return -EIO; > + } > + ASSERT(bbio->mirror_num == 1); > + } else { > + ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical, > + &map_length, &bbio, mirror_num); > + if (ret) { > + btrfs_bio_counter_dec(fs_info); > + bio_put(bio); > + return -EIO; > + } > + BUG_ON(mirror_num != bbio->mirror_num); > } > - BUG_ON(mirror_num != bbio->mirror_num); > - sector = bbio->stripes[mirror_num-1].physical >> 9; > + > + sector = bbio->stripes[bbio->mirror_num - 1].physical >> 9; > bio->bi_iter.bi_sector = sector; > - dev = bbio->stripes[mirror_num-1].dev; > + dev = bbio->stripes[bbio->mirror_num - 1].dev; > btrfs_put_bbio(bbio); > if (!dev || !dev->bdev || !dev->writeable) { > btrfs_bio_counter_dec(fs_info); -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Mar 27, 2017 at 06:59:44PM +0200, David Sterba wrote: > On Fri, Mar 24, 2017 at 12:13:35PM -0700, Liu Bo wrote: > > Now that scrub can fix data errors with the help of parity for raid56 > > profile, repair during read is able to as well. > > > > Although the mirror num in raid56 senario has different meanings, i.e. > > (typo: scenario) > Thanks! > > 0 or 1: read data directly > > > 1: do recover with parity, > > it could be fit into how we repair bad block during read. > > Could we possibly add some symbolic names for the RAID56 case? > Yes, we could do that here, but I'm afraid it might not be helpful because most of places still use mirror or mirror_num, such as btrfs_submit_bio_hook and btrfs_map_bio. > > > > The trick is to use BTRFS_MAP_READ instead of BTRFS_MAP_WRITE to get the > > device and position on it. > > Please also document the trick in the code before the following. > Good point. Thanks, -liubo > > + if (btrfs_is_parity_mirror(map_tree, logical, length, mirror_num)) { > > + /* use BTRFS_MAP_READ to get the phy dev and sector */ > > + ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, logical, > > + &map_length, &bbio, 0); > > + if (ret) { > > + btrfs_bio_counter_dec(fs_info); > > + bio_put(bio); > > + return -EIO; > > + } > > + ASSERT(bbio->mirror_num == 1); > > + } else { > > + ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical, > > + &map_length, &bbio, mirror_num); > > + if (ret) { > > + btrfs_bio_counter_dec(fs_info); > > + bio_put(bio); > > + return -EIO; > > + } > > + BUG_ON(mirror_num != bbio->mirror_num); > > } > > - BUG_ON(mirror_num != bbio->mirror_num); > > - sector = bbio->stripes[mirror_num-1].physical >> 9; > > + > > + sector = bbio->stripes[bbio->mirror_num - 1].physical >> 9; > > bio->bi_iter.bi_sector = sector; > > - dev = bbio->stripes[mirror_num-1].dev; > > + dev = bbio->stripes[bbio->mirror_num - 1].dev; > > btrfs_put_bbio(bbio); > > if (!dev || !dev->bdev || !dev->writeable) { > > btrfs_bio_counter_dec(fs_info); -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 1edb55d..0a44a43 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2009,10 +2009,6 @@ int repair_io_failure(struct btrfs_inode *inode, u64 start, u64 length, ASSERT(!(fs_info->sb->s_flags & MS_RDONLY)); BUG_ON(!mirror_num); - /* we can't repair anything in raid56 yet */ - if (btrfs_is_parity_mirror(map_tree, logical, length, mirror_num)) - return 0; - bio = btrfs_io_bio_alloc(GFP_NOFS, 1); if (!bio) return -EIO; @@ -2025,17 +2021,30 @@ int repair_io_failure(struct btrfs_inode *inode, u64 start, u64 length, * read repair operation. */ btrfs_bio_counter_inc_blocked(fs_info); - ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical, - &map_length, &bbio, mirror_num); - if (ret) { - btrfs_bio_counter_dec(fs_info); - bio_put(bio); - return -EIO; + if (btrfs_is_parity_mirror(map_tree, logical, length, mirror_num)) { + /* use BTRFS_MAP_READ to get the phy dev and sector */ + ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, logical, + &map_length, &bbio, 0); + if (ret) { + btrfs_bio_counter_dec(fs_info); + bio_put(bio); + return -EIO; + } + ASSERT(bbio->mirror_num == 1); + } else { + ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical, + &map_length, &bbio, mirror_num); + if (ret) { + btrfs_bio_counter_dec(fs_info); + bio_put(bio); + return -EIO; + } + BUG_ON(mirror_num != bbio->mirror_num); } - BUG_ON(mirror_num != bbio->mirror_num); - sector = bbio->stripes[mirror_num-1].physical >> 9; + + sector = bbio->stripes[bbio->mirror_num - 1].physical >> 9; bio->bi_iter.bi_sector = sector; - dev = bbio->stripes[mirror_num-1].dev; + dev = bbio->stripes[bbio->mirror_num - 1].dev; btrfs_put_bbio(bbio); if (!dev || !dev->bdev || !dev->writeable) { btrfs_bio_counter_dec(fs_info);