[PATCH 5.10 062/122] btrfs: introduce btrfs_lookup_match_dir

Greg Kroah-Hartman
2024-02-27T14:28:20Z

From: Marcos Paulo de Souza <mpdesouza@suse.com>

[ Upstream commit a7d1c5dc8632e9b370ad26478c468d4e4e29f263 ]

btrfs_search_slot is called in multiple places in dir-item.c to search
for a dir entry, and then calling btrfs_match_dir_name to return a
btrfs_dir_item.

In order to reduce the number of callers of btrfs_search_slot, create a
common function that looks for the dir key, and if found call
btrfs_match_dir_item_name.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 8dcbc26194eb ("btrfs: unify lookup return value when dir entry is missing")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/btrfs/dir-item.c | 76 +++++++++++++++++++++++----------------------
1 file changed, 39 insertions(+), 37 deletions(-)

diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index 863367c2c6205..1c0a7cd6b9b0a 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -171,6 +171,25 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, const char *name,
return 0;
}

+static struct btrfs_dir_item *btrfs_lookup_match_dir(
+ struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct btrfs_path *path,
+ struct btrfs_key *key, const char *name,
+ int name_len, int mod)
+{
+ const int ins_len = (mod < 0 ? -1 : 0);
+ const int cow = (mod != 0);
+ int ret;
+
+ ret = btrfs_search_slot(trans, root, key, path, ins_len, cow);
+ if (ret < 0)
+ return ERR_PTR(ret);
+ if (ret > 0)
+ return ERR_PTR(-ENOENT);
+
+ return btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
+}
+
/*
* lookup a directory item based on name. 'dir' is the objectid
* we're searching in, and 'mod' tells us if you plan on deleting the
@@ -182,23 +201,18 @@ struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
const char *name, int name_len,
int mod)
{
- int ret;
struct btrfs_key key;
- int ins_len = mod < 0 ? -1 : 0;
- int cow = mod != 0;
+ struct btrfs_dir_item *di;

key.objectid = dir;
key.type = BTRFS_DIR_ITEM_KEY;
-
key.offset = btrfs_name_hash(name, name_len);

- ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
- if (ret < 0)
- return ERR_PTR(ret);
- if (ret > 0)
+ di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod);
+ if (IS_ERR(di) && PTR_ERR(di) == -ENOENT)
return NULL;

- return btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
+ return di;
}

int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
@@ -212,7 +226,6 @@ int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
int slot;
struct btrfs_path *path;

-
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
@@ -221,20 +234,20 @@ int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
key.type = BTRFS_DIR_ITEM_KEY;
key.offset = btrfs_name_hash(name, name_len);

- ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
-
- /* return back any errors */
- if (ret < 0)
- goto out;
+ di = btrfs_lookup_match_dir(NULL, root, path, &key, name, name_len, 0);
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ /* Nothing found, we're safe */
+ if (ret == -ENOENT) {
+ ret = 0;
+ goto out;
+ }

- /* nothing found, we're safe */
- if (ret > 0) {
- ret = 0;
- goto out;
+ if (ret < 0)
+ goto out;
}

/* we found an item, look for our name in the item */
- di = btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
if (di) {
/* our exact name was found */
ret = -EEXIST;
@@ -275,21 +288,13 @@ btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
u64 objectid, const char *name, int name_len,
int mod)
{
- int ret;
struct btrfs_key key;
- int ins_len = mod < 0 ? -1 : 0;
- int cow = mod != 0;

key.objectid = dir;
key.type = BTRFS_DIR_INDEX_KEY;
key.offset = objectid;

- ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
- if (ret < 0)
- return ERR_PTR(ret);
- if (ret > 0)
- return ERR_PTR(-ENOENT);
- return btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
+ return btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod);
}

struct btrfs_dir_item *
@@ -346,21 +351,18 @@ struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
const char *name, u16 name_len,
int mod)
{
- int ret;
struct btrfs_key key;
- int ins_len = mod < 0 ? -1 : 0;
- int cow = mod != 0;
+ struct btrfs_dir_item *di;

key.objectid = dir;
key.type = BTRFS_XATTR_ITEM_KEY;
key.offset = btrfs_name_hash(name, name_len);
- ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
- if (ret < 0)
- return ERR_PTR(ret);
- if (ret > 0)
+
+ di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod);
+ if (IS_ERR(di) && PTR_ERR(di) == -ENOENT)
return NULL;

- return btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
+ return di;
}

/*
--
2.43.0