namei: invert WALK_PUT logics

... turning the condition for put_link() in walk_component() into
"WALK_MORE not passed and depth is non-zero".  Again, makes for
simpler arguments.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 7 insertions, 6 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 379168db782b..57d60922396e 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1747,7 +1747,7 @@ static inline int should_follow_link(struct nameidata *nd, struct path *link,
         return pick_link(nd, link, inode, seq);
 }
 
-enum {WALK_GET = 1, WALK_PUT = 2};
+enum {WALK_GET = 1, WALK_MORE = 2};
 
 static int walk_component(struct nameidata *nd, int flags)
 {
@@ -1762,7 +1762,7 @@ static int walk_component(struct nameidata *nd, int flags)
          */
         if (unlikely(nd->last_type != LAST_NORM)) {
                 err = handle_dots(nd, nd->last_type);
-                if (flags & WALK_PUT)
+                if (!(flags & WALK_MORE) && nd->depth)
                         put_link(nd);
                 return err;
         }
@@ -1789,7 +1789,7 @@ static int walk_component(struct nameidata *nd, int flags)
                 inode = d_backing_inode(path.dentry);
         }
 
-        if (flags & WALK_PUT)
+        if (!(flags & WALK_MORE) && nd->depth)
                 put_link(nd);
         err = should_follow_link(nd, &path, flags & WALK_GET, inode, seq);
         if (unlikely(err))
@@ -2104,9 +2104,10 @@ OK:
                         if (!name)
                                 return 0;
                         /* last component of nested symlink */
-                        err = walk_component(nd, WALK_GET | WALK_PUT);
-                } else {
                         err = walk_component(nd, WALK_GET);
+                } else {
+                        /* not the last component */
+                        err = walk_component(nd, WALK_GET | WALK_MORE);
                 }
                 if (err < 0)
                         return err;
@@ -2248,7 +2249,7 @@ static inline int lookup_last(struct nameidata *nd)
                 nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
 
         nd->flags &= ~LOOKUP_PARENT;
-        return walk_component(nd, nd->depth ? WALK_PUT : 0);
+        return walk_component(nd, 0);
 }
 
 /* Returns 0 and nd will be valid on success; Retuns error, otherwise. */