From 9a65b425bbbf1b76e55d8e067d1f4f90e3d561b6 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Tue, 27 Nov 2018 16:38:25 +0800 Subject: [PATCH] btrfs-progs: image: Fix block group item flags when restoring multi-device image to single device Since btrfs-image is just restoring tree blocks without really checking if that tree block contents makes sense, for multi-device image, block group items will keep the incorrect block group flags. For example, for a metadata RAID1 data RAID0 btrfs recovered to a single disk, its chunk tree will look like: item 1 key (FIRST_CHUNK_TREE CHUNK_ITEM 22020096) length 8388608 owner 2 stripe_len 65536 type SYSTEM item 2 key (FIRST_CHUNK_TREE CHUNK_ITEM 30408704) length 1073741824 owner 2 stripe_len 65536 type METADATA item 3 key (FIRST_CHUNK_TREE CHUNK_ITEM 1104150528) length 1073741824 owner 2 stripe_len 65536 type DATA All chunks have correct type (SINGLE). While its block group items will look like: item 1 key (22020096 BLOCK_GROUP_ITEM 8388608) block group used 16384 chunk_objectid 256 flags SYSTEM|RAID1 item 3 key (30408704 BLOCK_GROUP_ITEM 1073741824) block group used 114688 chunk_objectid 256 flags METADATA|RAID1 item 11 key (1104150528 BLOCK_GROUP_ITEM 1073741824) block group used 1572864 chunk_objectid 256 flags DATA|RAID0 All block group items still have the wrong profiles. And btrfs check (lowmem mode for better output) will report error for such image: ERROR: chunk[22020096 30408704) related block group item flags mismatch, wanted: 2, have: 18 ERROR: chunk[30408704 1104150528) related block group item flags mismatch, wanted: 4, have: 20 ERROR: chunk[1104150528 2177892352) related block group item flags mismatch, wanted: 1, have: 9 This patch will do an extra repair for block group items to fix the profile of them. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- image/main.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/image/main.c b/image/main.c index d9e4e673..d82e75f1 100644 --- a/image/main.c +++ b/image/main.c @@ -2164,6 +2164,51 @@ again: return 0; } +static void fixup_block_groups(struct btrfs_fs_info *fs_info) +{ + struct btrfs_block_group_cache *bg; + struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; + struct cache_extent *ce; + struct map_lookup *map; + u64 extra_flags; + + for (ce = search_cache_extent(&map_tree->cache_tree, 0); ce; + ce = next_cache_extent(ce)) { + map = container_of(ce, struct map_lookup, ce); + + bg = btrfs_lookup_block_group(fs_info, ce->start); + if (!bg) { + warning( + "cannot find block group %llu, filesystem may not be mountable", + ce->start); + continue; + } + extra_flags = map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK; + + if (bg->flags == map->type) + continue; + + /* Update the block group item and mark the bg dirty */ + bg->flags = map->type; + btrfs_set_block_group_flags(&bg->item, bg->flags); + set_extent_bits(&fs_info->block_group_cache, ce->start, + ce->start + ce->size - 1, BLOCK_GROUP_DIRTY); + + /* + * Chunk and bg flags can be different, changing bg flags + * without update avail_data/meta_alloc_bits will lead to + * ENOSPC. + * So here we set avail_*_alloc_bits to match chunk types. + */ + if (map->type & BTRFS_BLOCK_GROUP_DATA) + fs_info->avail_data_alloc_bits = extra_flags; + if (map->type & BTRFS_BLOCK_GROUP_METADATA) + fs_info->avail_metadata_alloc_bits = extra_flags; + if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) + fs_info->avail_system_alloc_bits = extra_flags; + } +} + static int fixup_chunks_and_devices(struct btrfs_fs_info *fs_info, struct mdrestore_struct *mdres, off_t dev_size) { @@ -2180,6 +2225,7 @@ static int fixup_chunks_and_devices(struct btrfs_fs_info *fs_info, return PTR_ERR(trans); } + fixup_block_groups(fs_info); ret = fixup_device_size(trans, mdres, dev_size); if (ret < 0) goto error;