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 <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b28fa3d..6a73d26 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -867,17 +867,7 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
num_refs = btrfs_extent_refs(leaf, ei);
extent_flags = btrfs_extent_flags(leaf, ei);
} else {
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- struct btrfs_extent_item_v0 *ei0;
- BUG_ON(item_size != sizeof(*ei0));
- ei0 = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_item_v0);
- num_refs = btrfs_extent_refs_v0(leaf, ei0);
- /* FIXME: this isn't correct for data */
- extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
-#else
BUG();
-#endif
}
BUG_ON(num_refs == 0);
} else {
@@ -1036,89 +1026,6 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
* tree block info structure.
*/
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
-static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
- struct btrfs_fs_info *fs_info,
- struct btrfs_path *path,
- u64 owner, u32 extra_size)
-{
- struct btrfs_root *root = fs_info->extent_root;
- struct btrfs_extent_item *item;
- struct btrfs_extent_item_v0 *ei0;
- struct btrfs_extent_ref_v0 *ref0;
- struct btrfs_tree_block_info *bi;
- struct extent_buffer *leaf;
- struct btrfs_key key;
- struct btrfs_key found_key;
- u32 new_size = sizeof(*item);
- u64 refs;
- int ret;
-
- leaf = path->nodes[0];
- BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
-
- btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
- ei0 = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_item_v0);
- refs = btrfs_extent_refs_v0(leaf, ei0);
-
- if (owner == (u64)-1) {
- while (1) {
- if (path->slots[0] >= btrfs_header_nritems(leaf)) {
- ret = btrfs_next_leaf(root, path);
- if (ret < 0)
- return ret;
- BUG_ON(ret > 0); /* Corruption */
- leaf = path->nodes[0];
- }
- btrfs_item_key_to_cpu(leaf, &found_key,
- path->slots[0]);
- BUG_ON(key.objectid != found_key.objectid);
- if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
- path->slots[0]++;
- continue;
- }
- ref0 = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_ref_v0);
- owner = btrfs_ref_objectid_v0(leaf, ref0);
- break;
- }
- }
- btrfs_release_path(path);
-
- if (owner < BTRFS_FIRST_FREE_OBJECTID)
- new_size += sizeof(*bi);
-
- new_size -= sizeof(*ei0);
- ret = btrfs_search_slot(trans, root, &key, path,
- new_size + extra_size, 1);
- if (ret < 0)
- return ret;
- BUG_ON(ret); /* Corruption */
-
- btrfs_extend_item(fs_info, path, new_size);
-
- leaf = path->nodes[0];
- item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
- btrfs_set_extent_refs(leaf, item, refs);
- /* FIXME: get real generation */
- btrfs_set_extent_generation(leaf, item, 0);
- if (owner < BTRFS_FIRST_FREE_OBJECTID) {
- btrfs_set_extent_flags(leaf, item,
- BTRFS_EXTENT_FLAG_TREE_BLOCK |
- BTRFS_BLOCK_FLAG_FULL_BACKREF);
- bi = (struct btrfs_tree_block_info *)(item + 1);
- /* FIXME: get first key of the block */
- memzero_extent_buffer(leaf, (unsigned long)bi, sizeof(*bi));
- btrfs_set_tree_block_level(leaf, bi, (int)owner);
- } else {
- btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
- }
- btrfs_mark_buffer_dirty(leaf);
- return 0;
-}
-#endif
-
/*
* is_data == BTRFS_REF_TYPE_BLOCK, tree block type is required,
* is_data == BTRFS_REF_TYPE_DATA, data type is requried,
@@ -1247,17 +1154,6 @@ static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
if (parent) {
if (!ret)
return 0;
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- key.type = BTRFS_EXTENT_REF_V0_KEY;
- btrfs_release_path(path);
- ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
- if (ret < 0) {
- err = ret;
- goto fail;
- }
- if (!ret)
- return 0;
-#endif
goto fail;
}
@@ -1400,13 +1296,6 @@ static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
ref2 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_shared_data_ref);
num_refs = btrfs_shared_data_ref_count(leaf, ref2);
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
- struct btrfs_extent_ref_v0 *ref0;
- ref0 = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_ref_v0);
- num_refs = btrfs_ref_count_v0(leaf, ref0);
-#endif
} else {
BUG();
}
@@ -1422,14 +1311,6 @@ static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- else {
- struct btrfs_extent_ref_v0 *ref0;
- ref0 = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_ref_v0);
- btrfs_set_ref_count_v0(leaf, ref0, num_refs);
- }
-#endif
btrfs_mark_buffer_dirty(leaf);
}
return ret;
@@ -1469,13 +1350,6 @@ static noinline u32 extent_data_ref_count(struct btrfs_path *path,
ref2 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_shared_data_ref);
num_refs = btrfs_shared_data_ref_count(leaf, ref2);
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
- struct btrfs_extent_ref_v0 *ref0;
- ref0 = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_ref_v0);
- num_refs = btrfs_ref_count_v0(leaf, ref0);
-#endif
} else {
WARN_ON(1);
}
@@ -1503,15 +1377,6 @@ static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0)
ret = -ENOENT;
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- if (ret == -ENOENT && parent) {
- btrfs_release_path(path);
- key.type = BTRFS_EXTENT_REF_V0_KEY;
- ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
- if (ret > 0)
- ret = -ENOENT;
- }
-#endif
return ret;
}
@@ -1676,22 +1541,6 @@ int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, path->slots[0]);
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- if (item_size < sizeof(*ei)) {
- if (!insert) {
- err = -ENOENT;
- goto out;
- }
- ret = convert_extent_item_v0(trans, fs_info, path, owner,
- extra_size);
- if (ret < 0) {
- err = ret;
- goto out;
- }
- leaf = path->nodes[0];
- item_size = btrfs_item_size_nr(leaf, path->slots[0]);
- }
-#endif
BUG_ON(item_size < sizeof(*ei));
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
@@ -2416,17 +2265,6 @@ static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, path->slots[0]);
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- if (item_size < sizeof(*ei)) {
- ret = convert_extent_item_v0(trans, fs_info, path, (u64)-1, 0);
- if (ret < 0) {
- err = ret;
- goto out;
- }
- leaf = path->nodes[0];
- item_size = btrfs_item_size_nr(leaf, path->slots[0]);
- }
-#endif
BUG_ON(item_size < sizeof(*ei));
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
__run_delayed_extent_op(extent_op, leaf, ei);
@@ -3238,12 +3076,6 @@ static noinline int check_committed_ref(struct btrfs_root *root,
ret = 1;
item_size = btrfs_item_size_nr(leaf, path->slots[0]);
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- if (item_size < sizeof(*ei)) {
- WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
- goto out;
- }
-#endif
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
if (item_size != sizeof(*ei) +
@@ -6888,11 +6720,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
break;
extent_slot--;
}
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
- if (found_extent && item_size < sizeof(*ei))
- found_extent = 0;
-#endif
+
if (!found_extent) {
BUG_ON(iref);
ret = remove_extent_backref(trans, path, NULL,
@@ -6968,41 +6796,6 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, extent_slot);
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- if (item_size < sizeof(*ei)) {
- BUG_ON(found_extent || extent_slot != path->slots[0]);
- ret = convert_extent_item_v0(trans, info, path, owner_objectid,
- 0);
- if (ret < 0) {
- btrfs_abort_transaction(trans, ret);
- goto out;
- }
-
- btrfs_release_path(path);
- path->leave_spinning = 1;
-
- key.objectid = bytenr;
- key.type = BTRFS_EXTENT_ITEM_KEY;
- key.offset = num_bytes;
-
- ret = btrfs_search_slot(trans, extent_root, &key, path,
- -1, 1);
- if (ret) {
- btrfs_err(info,
- "umm, got %d back from search, was looking for %llu",
- ret, bytenr);
- btrfs_print_leaf(path->nodes[0]);
- }
- if (ret < 0) {
- btrfs_abort_transaction(trans, ret);
- goto out;
- }
-
- extent_slot = path->slots[0];
- leaf = path->nodes[0];
- item_size = btrfs_item_size_nr(leaf, extent_slot);
- }
-#endif
BUG_ON(item_size < sizeof(*ei));
ei = btrfs_item_ptr(leaf, extent_slot,
struct btrfs_extent_item);