[PATCH v2 4/4] afs: Remove redundant assignment to ret

From: David Howells
Date: Mon Jul 12 2021 - 12:28:18 EST


From: Jiapeng Chong <jiapeng.chong@xxxxxxxxxxxxxxxxx>

Variable ret is set to -ENOENT and -ENOMEM but this value is never
read as it is overwritten or not used later on, hence it is a
redundant assignment and can be removed.

Cleans up the following clang-analyzer warning:

fs/afs/dir.c:2014:4: warning: Value stored to 'ret' is never read
[clang-analyzer-deadcode.DeadStores].

fs/afs/dir.c:659:2: warning: Value stored to 'ret' is never read
[clang-analyzer-deadcode.DeadStores].

[DH made the following modifications:

- In afs_rename(), -ENOMEM should be placed in op->error instead of ret,
rather than the assignment being removed entirely. afs_put_operation()
will pick it up from there and return it.

- If afs_sillyrename() fails, its error code should be placed in op->error
rather than in ret also.
]

Fixes: e49c7b2f6de7 ("afs: Build an abstraction around an "operation" concept")
Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
Signed-off-by: Jiapeng Chong <jiapeng.chong@xxxxxxxxxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Reviewed-by: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
cc: linux-afs@xxxxxxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/1619691492-83866-1-git-send-email-jiapeng.chong@xxxxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/162609465444.3133237.7562832521724298900.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v1
---

fs/afs/dir.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index 78719f2f567e..ac829e63c570 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -656,7 +656,6 @@ static int afs_do_lookup_one(struct inode *dir, struct dentry *dentry,
return ret;
}

- ret = -ENOENT;
if (!cookie.found) {
_leave(" = -ENOENT [not found]");
return -ENOENT;
@@ -2020,17 +2019,20 @@ static int afs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,

if (d_count(new_dentry) > 2) {
/* copy the target dentry's name */
- ret = -ENOMEM;
op->rename.tmp = d_alloc(new_dentry->d_parent,
&new_dentry->d_name);
- if (!op->rename.tmp)
+ if (!op->rename.tmp) {
+ op->error = -ENOMEM;
goto error;
+ }

ret = afs_sillyrename(new_dvnode,
AFS_FS_I(d_inode(new_dentry)),
new_dentry, op->key);
- if (ret)
+ if (ret) {
+ op->error = ret;
goto error;
+ }

op->dentry_2 = op->rename.tmp;
op->rename.rehash = NULL;