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, 7 insertions, 6 deletions

diff --git a/fs/stat.c b/fs/stat.c
index 68510068a641..82680f2c01d2 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -62,7 +62,7 @@ int vfs_stat_fd(int dfd, char __user *name, struct kstat *stat)
 
         error = __user_walk_fd(dfd, name, LOOKUP_FOLLOW, &nd);
         if (!error) {
-                error = vfs_getattr(nd.mnt, nd.dentry, stat);
+                error = vfs_getattr(nd.path.mnt, nd.path.dentry, stat);
                 path_release(&nd);
         }
         return error;
@@ -82,7 +82,7 @@ int vfs_lstat_fd(int dfd, char __user *name, struct kstat *stat)
 
         error = __user_walk_fd(dfd, name, 0, &nd);
         if (!error) {
-                error = vfs_getattr(nd.mnt, nd.dentry, stat);
+                error = vfs_getattr(nd.path.mnt, nd.path.dentry, stat);
                 path_release(&nd);
         }
         return error;
@@ -302,14 +302,15 @@ asmlinkage long sys_readlinkat(int dfd, const char __user *path,
 
         error = __user_walk_fd(dfd, path, 0, &nd);
         if (!error) {
-                struct inode * inode = nd.dentry->d_inode;
+                struct inode *inode = nd.path.dentry->d_inode;
 
                 error = -EINVAL;
                 if (inode->i_op && inode->i_op->readlink) {
-                        error = security_inode_readlink(nd.dentry);
+                        error = security_inode_readlink(nd.path.dentry);
                         if (!error) {
-                                touch_atime(nd.mnt, nd.dentry);
-                                error = inode->i_op->readlink(nd.dentry, buf, bufsiz);
+                                touch_atime(nd.path.mnt, nd.path.dentry);
+                                error = inode->i_op->readlink(nd.path.dentry,
+                                                              buf, bufsiz);
                         }
                 }
                 path_release(&nd);