[patch] ceph: checking for IS_ERR instead of NULL

[Dan Carpenter]

ceph_osdc_alloc_request() returns NULL on error, it never returns error
pointers.

Fixes: 5be0389dac66 ('ceph: re-send AIO write request when getting -EOLDSNAP 
error')
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index d37efdd..a52cf9b 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -698,8 +698,8 @@ static void ceph_aio_retry_work(struct work_struct *work)
 
        req = ceph_osdc_alloc_request(orig_req->r_osdc, snapc, 2,
                        false, GFP_NOFS);
-       if (IS_ERR(req)) {
-               ret = PTR_ERR(req);
+       if (!req) {
+               ret = -ENOMEM;
                req = orig_req;
                goto out;
        }