Embed a struct path into struct nameidata instead of nd->{dentry,mnt}

This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.

Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
  <dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
  struct path in every place where the stack can be traversed
- it reduces the overall code size:

without patch series:
   text    data     bss     dec     hex filename
5321639  858418  715768 6895825  6938d1 vmlinux

with patch series:
   text    data     bss     dec     hex filename
5320026  858418  715768 6894212  693284 vmlinux

This patch:

Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index 2bbcc8151dc3..a119c863ff37 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -368,7 +368,8 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
                  * so we don't need to follow the mount.
                  */
                 if (d_mountpoint(dentry)) {
-                        if (!autofs4_follow_mount(&nd->mnt, &nd->dentry)) {
+                        if (!autofs4_follow_mount(&nd->path.mnt,
+                                                  &nd->path.dentry)) {
                                 status = -ENOENT;
                                 goto out_error;
                         }