diff options
| -rw-r--r-- | btrfs-find-root.c | 58 |
1 files changed, 57 insertions, 1 deletions
diff --git a/btrfs-find-root.c b/btrfs-find-root.c index cdbcca6d..74a52b7b 100644 --- a/btrfs-find-root.c +++ b/btrfs-find-root.c @@ -275,6 +275,61 @@ static int find_root(struct btrfs_root *root) return ret; } +/* + * Get reliable generation and level for given root. + * + * We have two sources of gen/level: superblock and tree root. + * superblock include the following level: + * Root, chunk, log + * and the following generations: + * Root, chunk, uuid + * Other gen/leven can only be read from its btrfs_tree_root if possible. + * + * Currently we only believe things from superblock. + */ +static void get_root_gen_and_level(u64 objectid, struct btrfs_fs_info *fs_info, + u64 *ret_gen, u8 *ret_level) +{ + struct btrfs_super_block *super = fs_info->super_copy; + u64 gen = (u64)-1; + u8 level = (u8)-1; + + switch (objectid) { + case BTRFS_ROOT_TREE_OBJECTID: + level = btrfs_super_root_level(super); + gen = btrfs_super_generation(super); + break; + case BTRFS_CHUNK_TREE_OBJECTID: + level = btrfs_super_chunk_root_level(super); + gen = btrfs_super_chunk_root_generation(super); + printf("Search for chunk root is not supported yet\n"); + break; + case BTRFS_TREE_LOG_OBJECTID: + level = btrfs_super_log_root_level(super); + gen = btrfs_super_log_root_transid(super); + break; + case BTRFS_UUID_TREE_OBJECTID: + gen = btrfs_super_uuid_tree_generation(super); + break; + } + if (gen != (u64)-1) { + printf("Superblock thinks the generation is %llu\n", gen); + if (ret_gen) + *ret_gen = gen; + } else { + printf("Superblock doesn't contain generation info for root %llu\n", + objectid); + } + if (level != (u8)-1) { + printf("Superblock thinks the level is %u\n", level); + if (ret_level) + *ret_level = level; + } else { + printf("Superblock doesn't contain the level info for root %llu\n", + objectid); + } +} + int main(int argc, char **argv) { struct btrfs_root *root; @@ -312,7 +367,8 @@ int main(int argc, char **argv) } if (search_generation == 0) - search_generation = btrfs_super_generation(root->fs_info->super_copy); + get_root_gen_and_level(search_objectid, root->fs_info, + &search_generation, NULL); csum_size = btrfs_super_csum_size(root->fs_info->super_copy); ret = find_root(root); |