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>

1 files changed, 3 insertions, 3 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 76fb76a0818b..5a9291c31881 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1585,7 +1585,7 @@ static inline int walk_component(struct nameidata *nd, struct path *path,
                 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 @@ mountpoint_last(struct nameidata *nd, struct path *path)
         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 @@ retry_lookup:
 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;
         }