btrfs: rename btrfs_check_shared() to a more descriptive name

The function btrfs_check_shared() is supposed to be used to check if a
data extent is shared, but its name is too generic, may easily cause
confusion in the sense that it may be used for metadata extents.

So rename it to btrfs_is_data_extent_shared(), which will also make it
less confusing after the next change that adds a backref lookup cache for
the b+tree nodes that lead to the leaf that contains the file extent item
that points to the target data extent.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Filipe Manana 2022-09-01 14:18:27 +01:00 committed by David Sterba
parent 09fbc1c8e7
commit 8eedaddaab
3 changed files with 10 additions and 9 deletions

View File

@ -1511,8 +1511,8 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
return ret;
}
/**
* Check if an extent is shared or not
/*
* Check if a data extent is shared or not.
*
* @root: root inode belongs to
* @inum: inode number of the inode whose extent we are checking
@ -1520,7 +1520,7 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
* @roots: list of roots this extent is shared among
* @tmp: temporary list used for iteration
*
* btrfs_check_shared uses the backref walking code but will short
* btrfs_is_data_extent_shared uses the backref walking code but will short
* circuit as soon as it finds a root or inode that doesn't match the
* one passed in. This provides a significant performance benefit for
* callers (such as fiemap) which want to know whether the extent is
@ -1531,8 +1531,8 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
*
* Return: 0 if extent is not shared, 1 if it is shared, < 0 on error.
*/
int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr,
struct ulist *roots, struct ulist *tmp)
int btrfs_is_data_extent_shared(struct btrfs_root *root, u64 inum, u64 bytenr,
struct ulist *roots, struct ulist *tmp)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_trans_handle *trans;

View File

@ -62,8 +62,8 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
u64 start_off, struct btrfs_path *path,
struct btrfs_inode_extref **ret_extref,
u64 *found_off);
int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr,
struct ulist *roots, struct ulist *tmp_ulist);
int btrfs_is_data_extent_shared(struct btrfs_root *root, u64 inum, u64 bytenr,
struct ulist *roots, struct ulist *tmp);
int __init btrfs_prelim_ref_init(void);
void __cold btrfs_prelim_ref_exit(void);

View File

@ -5585,8 +5585,9 @@ int extent_fiemap(struct btrfs_inode *inode, struct fiemap_extent_info *fieinfo,
* then we're just getting a count and we can skip the
* lookup stuff.
*/
ret = btrfs_check_shared(root, btrfs_ino(inode),
bytenr, roots, tmp_ulist);
ret = btrfs_is_data_extent_shared(root, btrfs_ino(inode),
bytenr, roots,
tmp_ulist);
if (ret < 0)
goto out_free;
if (ret)