Re: [PATCH] btrfs: simplify btrfs_lookup_inode_extref() by removing unused parameters

[Qu Wenruo <quwenruo.btrfs@gmx.com>]

在 2025/6/14 13:09, Sun YangKai 写道:
> The `btrfs_lookup_inode_extref()` function no longer requires transaction
> handle, insert length, or COW flag, as the onlycaller now perform a
> read-only lookup using `trans = NULL`, `ins_len = 0`, and `cow = 0`.
> 
> This patch removes the unused parameters from the function signature and
> call sites, simplifying the interface and clarifying its current usage as
> a read-only lookup helper.
> 
> No functional changes intended.
> 
> Signed-off-by: Sun YangKai <sunk67188@gmail.com>

Reviewed-by: Qu Wenruo <wqu@suse.com>

This function is introduced in the early days where extref feature is 
introduced by commit f186373fef00 ("btrfs: extended inode refs").
Then some cleanup is done in commit 33b98f227111 ("btrfs: cleanup: 
removed unused 'btrfs_get_inode_ref_index'"), which removed the only 
caller passing trans and other COW specific options.

Thanks,
Qu

> ---
>   fs/btrfs/inode-item.c | 8 +++-----
>   fs/btrfs/inode-item.h | 4 +---
>   fs/btrfs/tree-log.c   | 5 ++---
>   3 files changed, 6 insertions(+), 11 deletions(-)
> 
> diff --git a/fs/btrfs/inode-item.c b/fs/btrfs/inode-item.c
> index a61c3540d67b..a35abe10de64 100644
> --- a/fs/btrfs/inode-item.c
> +++ b/fs/btrfs/inode-item.c
> @@ -79,12 +79,10 @@ struct btrfs_inode_extref *btrfs_find_name_in_ext_backref(
>   
>   /* Returns NULL if no extref found */
>   struct btrfs_inode_extref *
> -btrfs_lookup_inode_extref(struct btrfs_trans_handle *trans,
> -			  struct btrfs_root *root,
> +btrfs_lookup_inode_extref(struct btrfs_root *root,
>   			  struct btrfs_path *path,
>   			  const struct fscrypt_str *name,
> -			  u64 inode_objectid, u64 ref_objectid, int ins_len,
> -			  int cow)
> +			  u64 inode_objectid, u64 ref_objectid)
>   {
>   	int ret;
>   	struct btrfs_key key;
> @@ -93,7 +91,7 @@ btrfs_lookup_inode_extref(struct btrfs_trans_handle *trans,
>   	key.type = BTRFS_INODE_EXTREF_KEY;
>   	key.offset = btrfs_extref_hash(ref_objectid, name->name, name->len);
>   
> -	ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
> +	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
>   	if (ret < 0)
>   		return ERR_PTR(ret);
>   	if (ret > 0)
> diff --git a/fs/btrfs/inode-item.h b/fs/btrfs/inode-item.h
> index c11b97fdccc4..c57661bdde30 100644
> --- a/fs/btrfs/inode-item.h
> +++ b/fs/btrfs/inode-item.h
> @@ -102,12 +102,10 @@ int btrfs_lookup_inode(struct btrfs_trans_handle *trans,
>   		       struct btrfs_key *location, int mod);
>   
>   struct btrfs_inode_extref *btrfs_lookup_inode_extref(
> -			  struct btrfs_trans_handle *trans,
>   			  struct btrfs_root *root,
>   			  struct btrfs_path *path,
>   			  const struct fscrypt_str *name,
> -			  u64 inode_objectid, u64 ref_objectid, int ins_len,
> -			  int cow);
> +			  u64 inode_objectid, u64 ref_objectid);
>   
>   struct btrfs_inode_ref *btrfs_find_name_in_backref(const struct extent_buffer *leaf,
>   						   int slot,
> diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
> index 97e933113b82..66fff2bc60f3 100644
> --- a/fs/btrfs/tree-log.c
> +++ b/fs/btrfs/tree-log.c
> @@ -1125,9 +1125,8 @@ static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
>   	btrfs_release_path(path);
>   
>   	/* Same search but for extended refs */
> -	extref = btrfs_lookup_inode_extref(NULL, root, path, name,
> -					   inode_objectid, parent_objectid, 0,
> -					   0);
> +	extref = btrfs_lookup_inode_extref(root, path, name,
> +					   inode_objectid, parent_objectid);
>   	if (IS_ERR(extref)) {
>   		return PTR_ERR(extref);
>   	} else if (extref) {