The comparison functions for protocol negotiation (introduced in commit
d24fbcda0c4988322949df3d759f1cfb32b32953) were confusing.
Separate out the comparison and value update parts.

Signed-off-by: Joel Becker <[EMAIL PROTECTED]>
---
 fs/ocfs2/dlm/dlmdomain.c |  102 ++++++++++++++++++++++------------------------
 1 files changed, 49 insertions(+), 53 deletions(-)

diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 638d2eb..de802a7 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -144,8 +144,6 @@ static int dlm_cancel_join_handler(struct o2net_msg *msg, 
u32 len, void *data,
                                   void **ret_data);
 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
                                   void **ret_data);
-static int dlm_protocol_compare(struct dlm_protocol_version *existing,
-                               struct dlm_protocol_version *request);
 
 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
 
@@ -681,36 +679,48 @@ void dlm_unregister_domain(struct dlm_ctxt *dlm)
 }
 EXPORT_SYMBOL_GPL(dlm_unregister_domain);
 
+/*
+ * Compare a requested locking protocol version against the current one.
+ *
+ * If the major numbers are different, they are incompatible.
+ * If the current minor is greater than the request, they are incompatible.
+ * If the current minor is less than or equal to the request, they are
+ * compatible, and the requester should run at the current minor version.
+ */
+static int dlm_protocol_compatible(struct dlm_protocol_version *existing,
+                                  struct dlm_protocol_version *request)
+{
+       if (existing->pv_major != request->pv_major)
+               return 0;
+
+       if (existing->pv_minor > request->pv_minor)
+               return 0;
+
+       return 1;
+}
+
 static int dlm_query_join_proto_check(char *proto_type, int node,
                                      struct dlm_protocol_version *ours,
                                      struct dlm_protocol_version *request)
 {
-       int rc;
-       struct dlm_protocol_version proto = *request;
+       int compatible = dlm_protocol_compatible(ours, request);
 
-       if (!dlm_protocol_compare(ours, &proto)) {
+       if (compatible)
                mlog(0,
                     "node %u wanted to join with %s locking protocol "
                     "%u.%u, we respond with %u.%u\n",
                     node, proto_type,
-                    request->pv_major,
-                    request->pv_minor,
-                    proto.pv_major, proto.pv_minor);
-               request->pv_minor = proto.pv_minor;
-               rc = 0;
-       } else {
+                    request->pv_major, request->pv_minor,
+                    ours->pv_major, ours->pv_minor);
+       else
                mlog(ML_NOTICE,
                     "Node %u wanted to join with %s locking "
                     "protocol %u.%u, but we have %u.%u, disallowing\n",
                     node, proto_type,
-                    request->pv_major,
-                    request->pv_minor,
-                    ours->pv_major,
-                    ours->pv_minor);
-               rc = 1;
-       }
+                    request->pv_major, request->pv_minor,
+                    ours->pv_major, ours->pv_minor);
 
-       return rc;
+       return compatible;
 }
 
 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
@@ -806,21 +816,23 @@ static int dlm_query_join_handler(struct o2net_msg *msg, 
u32 len, void *data,
                        /* Make sure we speak compatible locking protocols.  */
                        if (dlm_query_join_proto_check("DLM", bit,
                                                       &dlm->dlm_locking_proto,
-                                                      &query->dlm_proto)) {
-                               response.packet.code =
-                                       JOIN_PROTOCOL_MISMATCH;
-                       } else if (dlm_query_join_proto_check("fs", bit,
-                                                             
&dlm->fs_locking_proto,
-                                                             
&query->fs_proto)) {
-                               response.packet.code =
-                                       JOIN_PROTOCOL_MISMATCH;
-                       } else {
+                                                      &query->dlm_proto) &&
+                           dlm_query_join_proto_check("fs", bit,
+                                                      &dlm->fs_locking_proto,
+                                                      &query->fs_proto)) {
+                               /*
+                                * We're compatible, return our
+                                * minor number
+                                */
                                response.packet.dlm_minor =
-                                       query->dlm_proto.pv_minor;
+                                       dlm->dlm_locking_proto.pv_minor;
                                response.packet.fs_minor =
-                                       query->fs_proto.pv_minor;
+                                       dlm->fs_locking_proto.pv_minor;
                                response.packet.code = JOIN_OK;
                                __dlm_set_joining_node(dlm, query->node_idx);
+                       } else {
+                               response.packet.code =
+                                       JOIN_PROTOCOL_MISMATCH;
                        }
                }
 
@@ -1546,29 +1558,6 @@ leave:
 }
 
 /*
- * Compare a requested locking protocol version against the current one.
- *
- * If the major numbers are different, they are incompatible.
- * If the current minor is greater than the request, they are incompatible.
- * If the current minor is less than or equal to the request, they are
- * compatible, and the requester should run at the current minor version.
- */
-static int dlm_protocol_compare(struct dlm_protocol_version *existing,
-                               struct dlm_protocol_version *request)
-{
-       if (existing->pv_major != request->pv_major)
-               return 1;
-
-       if (existing->pv_minor > request->pv_minor)
-               return 1;
-
-       if (existing->pv_minor < request->pv_minor)
-               request->pv_minor = existing->pv_minor;
-
-       return 0;
-}
-
-/*
  * dlm_register_domain: one-time setup per "domain".
  *
  * The filesystem passes in the requested locking version via proto.
@@ -1620,7 +1609,14 @@ retry:
                        goto retry;
                }
 
-               if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
+               if (dlm_protocol_compatible(&dlm->fs_locking_proto, fs_proto)) {
+                       /*
+                        * We're compatible, and we run at the minor
+                        * number negotiated
+                        */
+                       fs_proto->pv_minor =
+                               dlm->fs_locking_proto.pv_minor;
+               } else {
                        mlog(ML_ERROR,
                             "Requested locking protocol version is not "
                             "compatible with already registered domain "
-- 
1.5.3.8

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