[PATCH v2 2/2] btrfs: zoned: bail out if we can't read a reliable write pointer
From: Johannes Thumshirn <hidden>
Date: 2021-05-04 08:31:43
Subsystem:
btrfs file system, filesystems (vfs and infrastructure), the rest · Maintainers:
Chris Mason, David Sterba, Alexander Viro, Christian Brauner, Linus Torvalds
If we can't read a reliable write pointer from a sequential zone fail creating the block group with an I/O error. Also if the read write pointer is beyond the end of the respective zone, fail the creation of the block group on this zone with an I/O error. While this could also happen in real world scenarios with misbehaving drives, this issue addresses a problem uncovered by xfstest's test case generic/475. Signed-off-by: Johannes Thumshirn <redacted> --- fs/btrfs/zoned.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 6edf88580f47..743334cf8bdd 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c@@ -1191,6 +1191,13 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new) switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { case 0: /* single */ + if (alloc_offsets[0] == WP_MISSING_DEV) { + btrfs_err(fs_info, + "zoned: cannot read write pointer for zone %llu", + physical >> ilog2(fs_info->zone_size)); + ret = -EIO; + goto out; + } cache->alloc_offset = alloc_offsets[0]; break; case BTRFS_BLOCK_GROUP_DUP:
@@ -1208,6 +1215,13 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new) } out: + if (cache->alloc_offset > fs_info->zone_size) { + btrfs_err(fs_info, + "zoned: write pointer %llu in BG %llu behind end of zone", + cache->alloc_offset, logical); + ret = -EIO; + } + /* An extent is allocated after the write pointer */ if (!ret && num_conventional && last_alloc > cache->alloc_offset) { btrfs_err(fs_info,
--
2.31.1