NFS: Fix a bug in nfs_fscache_release_page()

commit 2c1740098c708b465e87637b237feb2fd98f129a upstream.

Not having an fscache cookie is perfectly valid if the user didn't mount
with the fscache option.

This patch fixes http://bugzilla.kernel.org/show_bug.cgi?id=15234

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/nfs/fscache.c b/fs/nfs/fscache.c
index fa588006588dd3403bb9a883eedc79ddc4588655..237874f1af23697d3d092147eaa39bcf25958006 100644 (file)
--- a/fs/nfs/fscache.c
+++ b/fs/nfs/fscache.c
@@ -354,12 +354,11 @@ void nfs_fscache_reset_inode_cookie(struct inode *inode)
  */
 int nfs_fscache_release_page(struct page *page, gfp_t gfp)
 {
-       struct nfs_inode *nfsi = NFS_I(page->mapping->host);
-       struct fscache_cookie *cookie = nfsi->fscache;
-
-       BUG_ON(!cookie);
-
        if (PageFsCache(page)) {
+               struct nfs_inode *nfsi = NFS_I(page->mapping->host);
+               struct fscache_cookie *cookie = nfsi->fscache;
+
+               BUG_ON(!cookie);
                dfprintk(FSCACHE, "NFS: fscache releasepage (0x%p/0x%p/0x%p)\n",
                         cookie, page, nfsi);