libceph: make ceph_con_revoke_message() a msg op

ceph_con_revoke_message() is passed both a message and a ceph
connection.  A ceph_msg allocated for incoming messages on a
connection always has a pointer to that connection, so there's no
need to provide the connection when revoking such a message.

Note that the existing logic does not preclude the message supplied
being a null/bogus message pointer.  The only user of this interface
is the OSD client, and the only value an osd client passes is a
request's r_reply field.  That is always non-null (except briefly in
an error path in ceph_osdc_alloc_request(), and that drops the
only reference so the request won't ever have a reply to revoke).
So we can safely assume the passed-in message is non-null, but add a
BUG_ON() to make it very obvious we are imposing this restriction.

Rename the function ceph_msg_revoke_incoming() to reflect that it is
really an operation on an incoming message.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index ad78705a4aff..c178c770acb4 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -140,10 +140,9 @@ void ceph_osdc_release_request(struct kref *kref)
         if (req->r_request)
                 ceph_msg_put(req->r_request);
         if (req->r_con_filling_msg) {
-                dout("release_request revoking pages %p from con %p\n",
+                dout("%s revoking pages %p from con %p\n", __func__,
                      req->r_pages, req->r_con_filling_msg);
-                ceph_con_revoke_message(req->r_con_filling_msg,
-                                      req->r_reply);
+                ceph_msg_revoke_incoming(req->r_reply);
                 req->r_con_filling_msg->ops->put(req->r_con_filling_msg);
         }
         if (req->r_reply)
@@ -2022,9 +2021,9 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
         }
 
         if (req->r_con_filling_msg) {
-                dout("get_reply revoking msg %p from old con %p\n",
+                dout("%s revoking msg %p from old con %p\n", __func__,
                      req->r_reply, req->r_con_filling_msg);
-                ceph_con_revoke_message(req->r_con_filling_msg, req->r_reply);
+                ceph_msg_revoke_incoming(req->r_reply);
                 req->r_con_filling_msg->ops->put(req->r_con_filling_msg);
                 req->r_con_filling_msg = NULL;
         }