diff options
| -rw-r--r-- | fs/btrfs/ctree.h | 3 | ||||
| -rw-r--r-- | fs/btrfs/disk-io.c | 9 | ||||
| -rw-r--r-- | fs/btrfs/free-space-tree.c | 2 | ||||
| -rw-r--r-- | include/uapi/linux/btrfs.h | 12 |
4 files changed, 24 insertions, 2 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 33fe035..791e47c 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -251,7 +251,8 @@ struct btrfs_super_block { #define BTRFS_FEATURE_COMPAT_SAFE_CLEAR 0ULL #define BTRFS_FEATURE_COMPAT_RO_SUPP \ - (BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE) + (BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE | \ + BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID) #define BTRFS_FEATURE_COMPAT_RO_SAFE_SET 0ULL #define BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR 0ULL diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index c0bfc6c..3dede6d 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -2566,6 +2566,7 @@ int open_ctree(struct super_block *sb, int num_backups_tried = 0; int backup_index = 0; int max_active; + int clear_free_space_tree = 0; tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL); chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info, GFP_KERNEL); @@ -3131,6 +3132,14 @@ retry_root_backup: if (btrfs_test_opt(fs_info, CLEAR_CACHE) && btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + clear_free_space_tree = 1; + } else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) && + !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) { + btrfs_warn(fs_info, "free space tree is invalid"); + clear_free_space_tree = 1; + } + + if (clear_free_space_tree) { btrfs_info(fs_info, "clearing free space tree"); ret = btrfs_clear_free_space_tree(fs_info); if (ret) { diff --git a/fs/btrfs/free-space-tree.c b/fs/btrfs/free-space-tree.c index 8fd85bf..ea605ff 100644 --- a/fs/btrfs/free-space-tree.c +++ b/fs/btrfs/free-space-tree.c @@ -1182,6 +1182,7 @@ int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info) } btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE); + btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); fs_info->creating_free_space_tree = 0; ret = btrfs_commit_transaction(trans, tree_root); @@ -1250,6 +1251,7 @@ int btrfs_clear_free_space_tree(struct btrfs_fs_info *fs_info) return PTR_ERR(trans); btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE); + btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); fs_info->free_space_root = NULL; ret = clear_free_space_tree(trans, free_space_root); diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index ac5eacd..db4c253 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -239,7 +239,17 @@ struct btrfs_ioctl_fs_info_args { * Used by: * struct btrfs_ioctl_feature_flags */ -#define BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE (1ULL << 0) +#define BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE (1ULL << 0) +/* + * Older kernels (< 4.9) on big-endian systems produced broken free space tree + * bitmaps, and btrfs-progs also used to corrupt the free space tree (versions + * < 4.7.3). If this bit is clear, then the free space tree cannot be trusted. + * btrfs-progs can also intentionally clear this bit to ask the kernel to + * rebuild the free space tree, however this might not work on older kernels + * that do not know about this bit. If not sure, clear the cache manually on + * first mount when booting older kernel versions. + */ +#define BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID (1ULL << 1) #define BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF (1ULL << 0) #define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL (1ULL << 1) |