take unlazy_walk() into umount_lookup_last()

... and massage it a bit to reduce nesting

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/namei.c b/fs/namei.c
index f415c6683a837ac3cb1c5bf1d9600b6a3aec9d7e..0ab9e6756f3daa825a2d2f9f98014d275809db50 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2256,19 +2256,22 @@ umount_lookup_last(struct nameidata *nd, struct path *path)
        struct dentry *dentry;
        struct dentry *dir = nd->path.dentry;
 
-       if (unlikely(nd->flags & LOOKUP_RCU)) {
-               WARN_ON_ONCE(1);
-               error = -ECHILD;
-               goto error_check;
+       /* If we're in rcuwalk, drop out of it to handle last component */
+       if (nd->flags & LOOKUP_RCU) {
+               if (unlazy_walk(nd, NULL)) {
+                       error = -ECHILD;
+                       goto out;
+               }
        }
 
        nd->flags &= ~LOOKUP_PARENT;
 
        if (unlikely(nd->last_type != LAST_NORM)) {
                error = handle_dots(nd, nd->last_type);
-               if (!error)
-                       dentry = dget(nd->path.dentry);
-               goto error_check;
+               if (error)
+                       goto out;
+               dentry = dget(nd->path.dentry);
+               goto done;
        }
 
        mutex_lock(&dir->d_inode->i_mutex);
@@ -2282,28 +2285,28 @@ umount_lookup_last(struct nameidata *nd, struct path *path)
                dentry = d_alloc(dir, &nd->last);
                if (!dentry) {
                        error = -ENOMEM;
-               } else {
-                       dentry = lookup_real(dir->d_inode, dentry, nd->flags);
-                       if (IS_ERR(dentry))
-                               error = PTR_ERR(dentry);
+                       goto out;
                }
+               dentry = lookup_real(dir->d_inode, dentry, nd->flags);
+               error = PTR_ERR(dentry);
+               if (IS_ERR(dentry))
+                       goto out;
        }
        mutex_unlock(&dir->d_inode->i_mutex);
 
-error_check:
-       if (!error) {
-               if (!dentry->d_inode) {
-                       error = -ENOENT;
-                       dput(dentry);
-               } else {
-                       path->dentry = dentry;
-                       path->mnt = mntget(nd->path.mnt);
-                       if (should_follow_link(dentry->d_inode,
-                                               nd->flags & LOOKUP_FOLLOW))
-                               return 1;
-                       follow_mount(path);
-               }
+done:
+       if (!dentry->d_inode) {
+               error = -ENOENT;
+               dput(dentry);
+               goto out;
        }
+       path->dentry = dentry;
+       path->mnt = mntget(nd->path.mnt);
+       if (should_follow_link(dentry->d_inode, nd->flags & LOOKUP_FOLLOW))
+               return 1;
+       follow_mount(path);
+       error = 0;
+out:
        terminate_walk(nd);
        return error;
 }
@@ -2334,15 +2337,6 @@ path_umountat(int dfd, const char *name, struct path *path, unsigned int flags)
        if (err)
                goto out;
 
-       /* If we're in rcuwalk, drop out of it to handle last component */
-       if (nd.flags & LOOKUP_RCU) {
-               err = unlazy_walk(&nd, NULL);
-               if (err) {
-                       terminate_walk(&nd);
-                       goto out;
-               }
-       }
-
        err = umount_lookup_last(&nd, path);
        while (err > 0) {
                void *cookie;