[PATCH] namespace.c: split mark_mounts_for_expiry()

This patch splits the mark_mounts_for_expiry() function.  It's too complex and
too deeply nested, even without the bugfix in the following patch.

Otherwise code is completely the same.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 39 insertions, 32 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index ea555a36c314..d82cf18a1a94 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -825,6 +825,44 @@ unlock:
 
 EXPORT_SYMBOL_GPL(do_add_mount);
 
+static void expire_mount(struct vfsmount *mnt, struct list_head *mounts)
+{
+        spin_lock(&vfsmount_lock);
+
+        /*
+         * Check that it is still dead: the count should now be 2 - as
+         * contributed by the vfsmount parent and the mntget above
+         */
+        if (atomic_read(&mnt->mnt_count) == 2) {
+                struct nameidata old_nd;
+
+                /* delete from the namespace */
+                list_del_init(&mnt->mnt_list);
+                detach_mnt(mnt, &old_nd);
+                spin_unlock(&vfsmount_lock);
+                path_release(&old_nd);
+
+                /*
+                 * Now lay it to rest if this was the last ref on the superblock
+                 */
+                if (atomic_read(&mnt->mnt_sb->s_active) == 1) {
+                        /* last instance - try to be smart */
+                        lock_kernel();
+                        DQUOT_OFF(mnt->mnt_sb);
+                        acct_auto_close(mnt->mnt_sb);
+                        unlock_kernel();
+                }
+                mntput(mnt);
+        } else {
+                /*
+                 * Someone brought it back to life whilst we didn't have any
+                 * locks held so return it to the expiration list
+                 */
+                list_add_tail(&mnt->mnt_fslink, mounts);
+                spin_unlock(&vfsmount_lock);
+        }
+}
+
 /*
  * process a list of expirable mountpoints with the intent of discarding any
  * mountpoints that aren't in use and haven't been touched since last we came
@@ -875,38 +913,7 @@ void mark_mounts_for_expiry(struct list_head *mounts)
 
                 spin_unlock(&vfsmount_lock);
                 down_write(&namespace->sem);
-                spin_lock(&vfsmount_lock);
-
-                /* check that it is still dead: the count should now be 2 - as
-                 * contributed by the vfsmount parent and the mntget above */
-                if (atomic_read(&mnt->mnt_count) == 2) {
-                        struct nameidata old_nd;
-
-                        /* delete from the namespace */
-                        list_del_init(&mnt->mnt_list);
-                        detach_mnt(mnt, &old_nd);
-                        spin_unlock(&vfsmount_lock);
-                        path_release(&old_nd);
-
-                        /* now lay it to rest if this was the last ref on the
-                         * superblock */
-                        if (atomic_read(&mnt->mnt_sb->s_active) == 1) {
-                                /* last instance - try to be smart */
-                                lock_kernel();
-                                DQUOT_OFF(mnt->mnt_sb);
-                                acct_auto_close(mnt->mnt_sb);
-                                unlock_kernel();
-                        }
-
-                        mntput(mnt);
-                } else {
-                        /* someone brought it back to life whilst we didn't
-                         * have any locks held so return it to the expiration
-                         * list */
-                        list_add_tail(&mnt->mnt_fslink, mounts);
-                        spin_unlock(&vfsmount_lock);
-                }
-
+                expire_mount(mnt, mounts);
                 up_write(&namespace->sem);
 
                 mntput(mnt);