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>

1 files changed, 27 insertions, 33 deletions

diff --git a/fs/namei.c b/fs/namei.c
index f415c6683a83..0ab9e6756f3d 100644
--- 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;