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| author | Josef Bacik <josef@toxicpanda.com> | 2020-10-16 11:29:18 -0400 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2020-12-08 15:53:41 +0100 |
| commit | 42437a6386ffeaaf200731e73d723ea491f3fe7d (patch) | |
| tree | d8c5d6ebb854ecdb34e61fe7d9f458656e1713f1 /fs/btrfs/block-rsv.c | |
| parent | 68319c18cb21ab472ce2c4ed572257a42455ac01 (diff) | |
| download | lwn-42437a6386ffeaaf200731e73d723ea491f3fe7d.tar.gz lwn-42437a6386ffeaaf200731e73d723ea491f3fe7d.zip | |
btrfs: introduce mount option rescue=ignorebadroots
In the face of extent root corruption, or any other core fs wide root
corruption we will fail to mount the file system. This makes recovery
kind of a pain, because you need to fall back to userspace tools to
scrape off data. Instead provide a mechanism to gracefully handle bad
roots, so we can at least mount read-only and possibly recover data from
the file system.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/block-rsv.c')
| -rw-r--r-- | fs/btrfs/block-rsv.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/btrfs/block-rsv.c b/fs/btrfs/block-rsv.c index bc920afe23bf..04a6226e0388 100644 --- a/fs/btrfs/block-rsv.c +++ b/fs/btrfs/block-rsv.c @@ -426,6 +426,14 @@ void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info) fs_info->delayed_block_rsv.space_info = space_info; fs_info->delayed_refs_rsv.space_info = space_info; + /* + * Our various recovery options can leave us with NULL roots, so check + * here and just bail before we go dereferencing NULLs everywhere. + */ + if (!fs_info->extent_root || !fs_info->csum_root || + !fs_info->dev_root || !fs_info->chunk_root || !fs_info->tree_root) + return; + fs_info->extent_root->block_rsv = &fs_info->delayed_refs_rsv; fs_info->csum_root->block_rsv = &fs_info->delayed_refs_rsv; fs_info->dev_root->block_rsv = &fs_info->global_block_rsv; |