nfsd4: simpler ordering of setclientid_confirm checks

The cases here divide into two main categories:

	- if there's an uncomfirmed record with a matching verifier,
	  then this is a "normal", succesful case: we're either creating
	  a new client, or updating an existing one.
	- otherwise, this is a weird case: a replay, or a server reboot.

Reordering to reflect that makes the code a bit more concise and the
logic a lot easier to understand.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 11 insertions, 13 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index e42b5670ddee..991a8a7414f7 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2245,18 +2245,21 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
         if (conf && !same_creds(&conf->cl_cred, &rqstp->rq_cred))
                 goto out;
         /* cases below refer to rfc 3530 section 14.2.34: */
-        if (conf && unconf && same_verf(&confirm, &unconf->cl_confirm)) {
-                /* case 1: callback update */
+        if (!unconf || !same_verf(&confirm, &unconf->cl_confirm)) {
+                if (conf && !unconf) /* case 2: probable retransmit */
+                        status = nfs_ok;
+                else /* case 4: client hasn't noticed we rebooted yet? */
+                        status = nfserr_stale_clientid;
+                goto out;
+        }
+        status = nfs_ok;
+        if (conf) { /* case 1: callback update */
                 nfsd4_change_callback(conf, &unconf->cl_cb_conn);
                 nfsd4_probe_callback(conf);
                 expire_client(unconf);
-                status = nfs_ok;
-        } else if (conf && !unconf) {
-                status = nfs_ok;
-        } else if (!conf && unconf
-                        && same_verf(&unconf->cl_confirm, &confirm)) {
-                /* case 3: normal case; new or rebooted client */
+        } else { /* case 3: normal case; new or rebooted client */
                 unsigned int hash = clientstr_hashval(unconf->cl_recdir);
+
                 conf = find_confirmed_client_by_str(unconf->cl_recdir, hash);
                 if (conf) {
                         nfsd4_client_record_remove(conf);
@@ -2264,11 +2267,6 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
                 }
                 move_to_confirmed(unconf);
                 nfsd4_probe_callback(unconf);
-                status = nfs_ok;
-        } else if ((!conf || !same_verf(&conf->cl_confirm, &confirm))
-            && (!unconf || !same_verf(&unconf->cl_confirm, &confirm))) {
-                /* case 4: client hasn't noticed we rebooted yet? */
-                status = nfserr_stale_clientid;
         }
 out:
         nfs4_unlock_state();