libceph: don't set flags in ceph_osdc_alloc_request()

The only thing ceph_osdc_alloc_request() really does with the
flags value it is passed is assign it to the newly-created
osd request structure.  Do that in the caller instead.

Both callers subsequently call ceph_osdc_build_request(), so have
that function (instead of ceph_osdc_alloc_request()) issue a warning
if a request comes through with neither the read nor write flags set.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index cd9c283..77ce1ed 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -171,7 +171,6 @@
 }
 
 struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
-					       int flags,
 					       struct ceph_snap_context *snapc,
 					       struct ceph_osd_req_op *ops,
 					       bool use_mempool,
@@ -208,10 +207,6 @@
 	INIT_LIST_HEAD(&req->r_req_lru_item);
 	INIT_LIST_HEAD(&req->r_osd_item);
 
-	req->r_flags = flags;
-
-	WARN_ON((flags & (CEPH_OSD_FLAG_READ|CEPH_OSD_FLAG_WRITE)) == 0);
-
 	/* create reply message */
 	if (use_mempool)
 		msg = ceph_msgpool_get(&osdc->msgpool_op_reply, 0);
@@ -347,6 +342,8 @@
 	u64 data_len = 0;
 	int i;
 
+	WARN_ON((flags & (CEPH_OSD_FLAG_READ|CEPH_OSD_FLAG_WRITE)) == 0);
+
 	head = msg->front.iov_base;
 	head->snapid = cpu_to_le64(snap_id);
 	op = (void *)(head + 1);
@@ -442,12 +439,12 @@
 	} else
 		ops[1].op = 0;
 
-	req = ceph_osdc_alloc_request(osdc, flags,
-					 snapc, ops,
+	req = ceph_osdc_alloc_request(osdc, snapc, ops,
 					 use_mempool,
 					 GFP_NOFS, NULL, NULL);
 	if (!req)
 		return ERR_PTR(-ENOMEM);
+	req->r_flags = flags;
 
 	/* calculate max write size */
 	r = calc_layout(vino, layout, off, plen, req, ops);