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>

2 files changed, 3 insertions, 3 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 44f16d9041e3..ffeefa3c2c77 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2341,10 +2341,10 @@ static int selinux_mount(char * dev_name,
 		return rc;
 
 	if (flags & MS_REMOUNT)
-		return superblock_has_perm(current, nd->mnt->mnt_sb,
+		return superblock_has_perm(current, nd->path.mnt->mnt_sb,
 		                           FILESYSTEM__REMOUNT, NULL);
 	else
-		return dentry_has_perm(current, nd->mnt, nd->dentry,
+		return dentry_has_perm(current, nd->path.mnt, nd->path.dentry,
 		                       FILE__MOUNTON);
 }
 
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 5b690482f8cb..2b5d6f72f678 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -325,7 +325,7 @@ static int smack_sb_statfs(struct dentry *dentry)
 static int smack_sb_mount(char *dev_name, struct nameidata *nd,
 			  char *type, unsigned long flags, void *data)
 {
-	struct superblock_smack *sbp = nd->mnt->mnt_sb->s_security;
+	struct superblock_smack *sbp = nd->path.mnt->mnt_sb->s_security;
 
 	return smk_curacc(sbp->smk_floor, MAY_WRITE);
 }