libceph: fix ceph_osdc_alloc_request error checks
ceph_osdc_alloc_request returns NULL on failure.
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 5a80f41..6b5dda1 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -470,8 +470,8 @@
snapc, ops,
use_mempool,
GFP_NOFS, NULL, NULL);
- if (IS_ERR(req))
- return req;
+ if (!req)
+ return NULL;
/* calculate max write size */
calc_layout(osdc, vino, layout, off, plen, req, ops);