[62/89] NFS: Fix a bug in nfs_fscache_release_page()

[Greg KH]

2.6.31-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>

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@xxxxxxxxxx>
Acked-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 fs/nfs/fscache.c |   21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

--- a/fs/nfs/fscache.c
+++ b/fs/nfs/fscache.c
@@ -337,21 +337,20 @@ void nfs_fscache_reset_inode_cookie(stru
  */
 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 (fscache_check_page_write(cookie, page)) {
-		if (!(gfp & __GFP_WAIT))
-			return 0;
-		fscache_wait_on_page_write(cookie, page);
-	}
-
 	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);
 
+		if (fscache_check_page_write(cookie, page)) {
+			if (!(gfp & __GFP_WAIT))
+				return 0;
+			fscache_wait_on_page_write(cookie, page);
+		}
+
 		fscache_uncache_page(cookie, page);
 		nfs_add_fscache_stats(page->mapping->host,
 				      NFSIOS_FSCACHE_PAGES_UNCACHED, 1);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/