VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
Where we have:
if (!dentry->d_inode || d_is_negative(dentry)) {
type constructions in pathwalk we should be able to eliminate the check of
d_inode and rely solely on the result of d_is_negative() or d_is_positive().
What we do have to take care to do is to read d_inode after calling a
d_is_xxx() typecheck function to get the barriering right.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index 76fb76a..5a9291c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1585,7 +1585,7 @@
inode = path->dentry->d_inode;
}
err = -ENOENT;
- if (!inode || d_is_negative(path->dentry))
+ if (d_is_negative(path->dentry))
goto out_path_put;
if (should_follow_link(path->dentry, follow)) {
@@ -2310,7 +2310,7 @@
mutex_unlock(&dir->d_inode->i_mutex);
done:
- if (!dentry->d_inode || d_is_negative(dentry)) {
+ if (d_is_negative(dentry)) {
error = -ENOENT;
dput(dentry);
goto out;
@@ -3038,7 +3038,7 @@
finish_lookup:
/* we _can_ be in RCU mode here */
error = -ENOENT;
- if (!inode || d_is_negative(path->dentry)) {
+ if (d_is_negative(path->dentry)) {
path_to_nameidata(path, nd);
goto out;
}