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>

6 files changed, 22 insertions, 20 deletions

diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index 973c5c3..f2bef5e 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -259,7 +259,7 @@ osf_statfs(char __user *path, struct osf_statfs __user *buffer, unsigned long bu
 
 	retval = user_path_walk(path, &nd);
 	if (!retval) {
-		retval = do_osf_statfs(nd.dentry, buffer, bufsiz);
+		retval = do_osf_statfs(nd.path.dentry, buffer, bufsiz);
 		path_release(&nd);
 	}
 	return retval;
diff --git a/arch/mips/kernel/sysirix.c b/arch/mips/kernel/sysirix.c
index d70c4e0..49d6292 100644
--- a/arch/mips/kernel/sysirix.c
+++ b/arch/mips/kernel/sysirix.c
@@ -694,7 +694,7 @@ asmlinkage int irix_statfs(const char __user *path,
 	if (error)
 		goto out;
 
-	error = vfs_statfs(nd.dentry, &kbuf);
+	error = vfs_statfs(nd.path.dentry, &kbuf);
 	if (error)
 		goto dput_and_out;
 
@@ -1360,7 +1360,7 @@ asmlinkage int irix_statvfs(char __user *fname, struct irix_statvfs __user *buf)
 	error = user_path_walk(fname, &nd);
 	if (error)
 		goto out;
-	error = vfs_statfs(nd.dentry, &kbuf);
+	error = vfs_statfs(nd.path.dentry, &kbuf);
 	if (error)
 		goto dput_and_out;
 
@@ -1611,7 +1611,7 @@ asmlinkage int irix_statvfs64(char __user *fname, struct irix_statvfs64 __user *
 	error = user_path_walk(fname, &nd);
 	if (error)
 		goto out;
-	error = vfs_statfs(nd.dentry, &kbuf);
+	error = vfs_statfs(nd.path.dentry, &kbuf);
 	if (error)
 		goto dput_and_out;
 
diff --git a/arch/parisc/hpux/sys_hpux.c b/arch/parisc/hpux/sys_hpux.c
index 3e025df..d7395af 100644
--- a/arch/parisc/hpux/sys_hpux.c
+++ b/arch/parisc/hpux/sys_hpux.c
@@ -219,7 +219,7 @@ asmlinkage long hpux_statfs(const char __user *path,
 	error = user_path_walk(path, &nd);
 	if (!error) {
 		struct hpux_statfs tmp;
-		error = vfs_statfs_hpux(nd.dentry, &tmp);
+		error = vfs_statfs_hpux(nd.path.dentry, &tmp);
 		if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
 			error = -EFAULT;
 		path_release(&nd);
diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c
index e6e6559..6d1228c 100644
--- a/arch/powerpc/platforms/cell/spufs/inode.c
+++ b/arch/powerpc/platforms/cell/spufs/inode.c
@@ -1,3 +1,4 @@
+
 /*
  * SPU file system
  *
@@ -592,7 +593,7 @@ long spufs_create(struct nameidata *nd, unsigned int flags, mode_t mode,
 
 	ret = -EINVAL;
 	/* check if we are on spufs */
-	if (nd->dentry->d_sb->s_type != &spufs_type)
+	if (nd->path.dentry->d_sb->s_type != &spufs_type)
 		goto out;
 
 	/* don't accept undefined flags */
@@ -600,9 +601,9 @@ long spufs_create(struct nameidata *nd, unsigned int flags, mode_t mode,
 		goto out;
 
 	/* only threads can be underneath a gang */
-	if (nd->dentry != nd->dentry->d_sb->s_root) {
+	if (nd->path.dentry != nd->path.dentry->d_sb->s_root) {
 		if ((flags & SPU_CREATE_GANG) ||
-		    !SPUFS_I(nd->dentry->d_inode)->i_gang)
+		    !SPUFS_I(nd->path.dentry->d_inode)->i_gang)
 			goto out;
 	}
 
@@ -618,16 +619,17 @@ long spufs_create(struct nameidata *nd, unsigned int flags, mode_t mode,
 	mode &= ~current->fs->umask;
 
 	if (flags & SPU_CREATE_GANG)
-		return spufs_create_gang(nd->dentry->d_inode,
-					dentry, nd->mnt, mode);
+		return spufs_create_gang(nd->path.dentry->d_inode,
+					 dentry, nd->path.mnt, mode);
 	else
-		return spufs_create_context(nd->dentry->d_inode,
-					dentry, nd->mnt, flags, mode, filp);
+		return spufs_create_context(nd->path.dentry->d_inode,
+					    dentry, nd->path.mnt, flags, mode,
+					    filp);
 
 out_dput:
 	dput(dentry);
 out_dir:
-	mutex_unlock(&nd->dentry->d_inode->i_mutex);
+	mutex_unlock(&nd->path.dentry->d_inode->i_mutex);
 out:
 	return ret;
 }
diff --git a/arch/sparc64/solaris/fs.c b/arch/sparc64/solaris/fs.c
index 9311bfe..516932e 100644
--- a/arch/sparc64/solaris/fs.c
+++ b/arch/sparc64/solaris/fs.c
@@ -434,8 +434,8 @@ asmlinkage int solaris_statvfs(u32 path, u32 buf)
 
 	error = user_path_walk(A(path),&nd);
 	if (!error) {
-		struct inode * inode = nd.dentry->d_inode;
-		error = report_statvfs(nd.mnt, inode, buf);
+		struct inode *inode = nd.path.dentry->d_inode;
+		error = report_statvfs(nd.path.mnt, inode, buf);
 		path_release(&nd);
 	}
 	return error;
@@ -464,8 +464,8 @@ asmlinkage int solaris_statvfs64(u32 path, u32 buf)
 	lock_kernel();
 	error = user_path_walk(A(path), &nd);
 	if (!error) {
-		struct inode * inode = nd.dentry->d_inode;
-		error = report_statvfs64(nd.mnt, inode, buf);
+		struct inode *inode = nd.path.dentry->d_inode;
+		error = report_statvfs64(nd.path.mnt, inode, buf);
 		path_release(&nd);
 	}
 	unlock_kernel();
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index ebb265c..19d579d 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -145,8 +145,8 @@ void mconsole_proc(struct mc_request *req)
 	}
 	up_write(&super->s_umount);
 
-	nd.dentry = super->s_root;
-	nd.mnt = NULL;
+	nd.path.dentry = super->s_root;
+	nd.path.mnt = NULL;
 	nd.flags = O_RDONLY + 1;
 	nd.last_type = LAST_ROOT;
 
@@ -159,7 +159,7 @@ void mconsole_proc(struct mc_request *req)
 		goto out_kill;
 	}
 
-	file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
+	file = dentry_open(nd.path.dentry, nd.path.mnt, O_RDONLY);
 	if (IS_ERR(file)) {
 		mconsole_reply(req, "Failed to open file", 1, 0);
 		goto out_kill;