From a79865c680d81220a1355cd13098e75227dc2994 Mon Sep 17 00:00:00 2001 From: Nikolay Borisov Date: Thu, 21 Jun 2018 09:45:00 +0300 Subject: btrfs: Remove V0 extent support The v0 compat code was introduced in commit 5d4f98a28c7d ("Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE)") 9 years ago, which was merged in 2.6.31. This means that the code is there to support filesystems which are _VERY_ old and if you are using btrfs on such an old kernel, you have much bigger problems. This coupled with the fact that no one is likely testing/maintining this code likely means it has bugs lurking. All things considered I think 43 kernel releases later it's high time this remnant of the past got removed. This patch removes all code wrapped in #ifdefs but leaves the BUG_ONs in case we have a v0 with no support intact as a sort of safety-net. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/relocation.c | 151 +------------------------------------------------- 1 file changed, 1 insertion(+), 150 deletions(-) (limited to 'fs/btrfs/relocation.c') diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 44722e939e34..6dfa92e5ceed 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -586,29 +586,6 @@ static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info, return btrfs_get_fs_root(fs_info, &key, false); } -#ifdef BTRFS_COMPAT_EXTENT_TREE_V0 -static noinline_for_stack -struct btrfs_root *find_tree_root(struct reloc_control *rc, - struct extent_buffer *leaf, - struct btrfs_extent_ref_v0 *ref0) -{ - struct btrfs_root *root; - u64 root_objectid = btrfs_ref_root_v0(leaf, ref0); - u64 generation = btrfs_ref_generation_v0(leaf, ref0); - - BUG_ON(root_objectid == BTRFS_TREE_RELOC_OBJECTID); - - root = read_fs_root(rc->extent_root->fs_info, root_objectid); - BUG_ON(IS_ERR(root)); - - if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) && - generation != btrfs_root_generation(&root->root_item)) - return NULL; - - return root; -} -#endif - static noinline_for_stack int find_inline_backref(struct extent_buffer *leaf, int slot, unsigned long *ptr, unsigned long *end) @@ -621,12 +598,6 @@ int find_inline_backref(struct extent_buffer *leaf, int slot, btrfs_item_key_to_cpu(leaf, &key, slot); item_size = btrfs_item_size_nr(leaf, slot); -#ifdef BTRFS_COMPAT_EXTENT_TREE_V0 - if (item_size < sizeof(*ei)) { - WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0)); - return 1; - } -#endif ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item); WARN_ON(!(btrfs_extent_flags(leaf, ei) & BTRFS_EXTENT_FLAG_TREE_BLOCK)); @@ -811,29 +782,8 @@ again: goto next; } -#ifdef BTRFS_COMPAT_EXTENT_TREE_V0 - if (key.type == BTRFS_SHARED_BLOCK_REF_KEY || - key.type == BTRFS_EXTENT_REF_V0_KEY) { - if (key.type == BTRFS_EXTENT_REF_V0_KEY) { - struct btrfs_extent_ref_v0 *ref0; - ref0 = btrfs_item_ptr(eb, path1->slots[0], - struct btrfs_extent_ref_v0); - if (key.objectid == key.offset) { - root = find_tree_root(rc, eb, ref0); - if (root && !should_ignore_root(root)) - cur->root = root; - else - list_add(&cur->list, &useless); - break; - } - if (is_cowonly_root(btrfs_ref_root_v0(eb, - ref0))) - cur->cowonly = 1; - } -#else ASSERT(key.type != BTRFS_EXTENT_REF_V0_KEY); if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) { -#endif if (key.objectid == key.offset) { /* * only root blocks of reloc trees use @@ -3333,48 +3283,6 @@ int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key, return 0; } -#ifdef BTRFS_COMPAT_EXTENT_TREE_V0 -static int get_ref_objectid_v0(struct reloc_control *rc, - struct btrfs_path *path, - struct btrfs_key *extent_key, - u64 *ref_objectid, int *path_change) -{ - struct btrfs_key key; - struct extent_buffer *leaf; - struct btrfs_extent_ref_v0 *ref0; - int ret; - int slot; - - leaf = path->nodes[0]; - slot = path->slots[0]; - while (1) { - if (slot >= btrfs_header_nritems(leaf)) { - ret = btrfs_next_leaf(rc->extent_root, path); - if (ret < 0) - return ret; - BUG_ON(ret > 0); - leaf = path->nodes[0]; - slot = path->slots[0]; - if (path_change) - *path_change = 1; - } - btrfs_item_key_to_cpu(leaf, &key, slot); - if (key.objectid != extent_key->objectid) - return -ENOENT; - - if (key.type != BTRFS_EXTENT_REF_V0_KEY) { - slot++; - continue; - } - ref0 = btrfs_item_ptr(leaf, slot, - struct btrfs_extent_ref_v0); - *ref_objectid = btrfs_ref_objectid_v0(leaf, ref0); - break; - } - return 0; -} -#endif - /* * helper to add a tree block to the list. * the major work is getting the generation and level of the block @@ -3408,22 +3316,7 @@ static int add_tree_block(struct reloc_control *rc, } generation = btrfs_extent_generation(eb, ei); } else { -#ifdef BTRFS_COMPAT_EXTENT_TREE_V0 - u64 ref_owner; - int ret; - - BUG_ON(item_size != sizeof(struct btrfs_extent_item_v0)); - ret = get_ref_objectid_v0(rc, path, extent_key, - &ref_owner, NULL); - if (ret < 0) - return ret; - BUG_ON(ref_owner >= BTRFS_MAX_LEVEL); - level = (int)ref_owner; - /* FIXME: get real generation */ - generation = 0; -#else BUG(); -#endif } btrfs_release_path(path); @@ -3781,12 +3674,7 @@ int add_data_references(struct reloc_control *rc, eb = path->nodes[0]; ptr = btrfs_item_ptr_offset(eb, path->slots[0]); end = ptr + btrfs_item_size_nr(eb, path->slots[0]); -#ifdef BTRFS_COMPAT_EXTENT_TREE_V0 - if (ptr + sizeof(struct btrfs_extent_item_v0) == end) - ptr = end; - else -#endif - ptr += sizeof(struct btrfs_extent_item); + ptr += sizeof(struct btrfs_extent_item); while (ptr < end) { iref = (struct btrfs_extent_inline_ref *)ptr; @@ -3832,13 +3720,8 @@ int add_data_references(struct reloc_control *rc, if (key.objectid != extent_key->objectid) break; -#ifdef BTRFS_COMPAT_EXTENT_TREE_V0 - if (key.type == BTRFS_SHARED_DATA_REF_KEY || - key.type == BTRFS_EXTENT_REF_V0_KEY) { -#else BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY); if (key.type == BTRFS_SHARED_DATA_REF_KEY) { -#endif ret = __add_tree_block(rc, key.offset, blocksize, blocks); } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { @@ -4086,39 +3969,7 @@ restart: BUG_ON(ret); } else { -#ifdef BTRFS_COMPAT_EXTENT_TREE_V0 - u64 ref_owner; - int path_change = 0; - - BUG_ON(item_size != - sizeof(struct btrfs_extent_item_v0)); - ret = get_ref_objectid_v0(rc, path, &key, &ref_owner, - &path_change); - if (ret < 0) { - err = ret; - break; - } - if (ref_owner < BTRFS_FIRST_FREE_OBJECTID) - flags = BTRFS_EXTENT_FLAG_TREE_BLOCK; - else - flags = BTRFS_EXTENT_FLAG_DATA; - - if (path_change) { - btrfs_release_path(path); - - path->search_commit_root = 1; - path->skip_locking = 1; - ret = btrfs_search_slot(NULL, rc->extent_root, - &key, path, 0, 0); - if (ret < 0) { - err = ret; - break; - } - BUG_ON(ret > 0); - } -#else BUG(); -#endif } if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { -- cgit v1.2.3