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, 12 insertions, 11 deletions

diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c
index 413ee2349d1a..bcd53c2fe781 100644
--- a/fs/cifs/cifs_dfs_ref.c
+++ b/fs/cifs/cifs_dfs_ref.c
@@ -259,18 +259,18 @@ static int add_mount_helper(struct vfsmount *newmnt, struct nameidata *nd,
         int err;
 
         mntget(newmnt);
-        err = do_add_mount(newmnt, nd, nd->mnt->mnt_flags, mntlist);
+        err = do_add_mount(newmnt, nd, nd->path.mnt->mnt_flags, mntlist);
         switch (err) {
         case 0:
-                dput(nd->dentry);
-                mntput(nd->mnt);
-                nd->mnt = newmnt;
-                nd->dentry = dget(newmnt->mnt_root);
+                dput(nd->path.dentry);
+                mntput(nd->path.mnt);
+                nd->path.mnt = newmnt;
+                nd->path.dentry = dget(newmnt->mnt_root);
                 break;
         case -EBUSY:
                 /* someone else made a mount here whilst we were busy */
-                while (d_mountpoint(nd->dentry) &&
-                       follow_down(&nd->mnt, &nd->dentry))
+                while (d_mountpoint(nd->path.dentry) &&
+                       follow_down(&nd->path.mnt, &nd->path.dentry))
                         ;
                 err = 0;
         default:
@@ -307,8 +307,8 @@ cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
 
         xid = GetXid();
 
-        dput(nd->dentry);
-        nd->dentry = dget(dentry);
+        dput(nd->path.dentry);
+        nd->path.dentry = dget(dentry);
 
         cifs_sb = CIFS_SB(dentry->d_inode->i_sb);
         ses = cifs_sb->tcon->ses;
@@ -340,7 +340,8 @@ cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
                                 rc = -EINVAL;
                                 goto out_err;
                         }
-                        mnt = cifs_dfs_do_refmount(nd->mnt, nd->dentry,
+                        mnt = cifs_dfs_do_refmount(nd->path.mnt,
+                                                nd->path.dentry,
                                                 referrals[i].node_name);
                         cFYI(1, ("%s: cifs_dfs_do_refmount:%s , mnt:%p",
                                          __FUNCTION__,
@@ -357,7 +358,7 @@ cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
         if (IS_ERR(mnt))
                 goto out_err;
 
-        nd->mnt->mnt_flags |= MNT_SHRINKABLE;
+        nd->path.mnt->mnt_flags |= MNT_SHRINKABLE;
         rc = add_mount_helper(mnt, nd, &cifs_dfs_automount_list);
 
 out: