From: J. Bruce Fields <bfields@citi.umich.edu>
Date: Thu, 22 Nov 2007 18:54:18 +0000 (-0500)
Subject: nfsd4: probe callback channel only once
X-Git-Tag: v2.6.25-rc1~1072^2~99
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=46f8a64bae11f5c9b15b4401f6e9863281999b66;p=linux-2.6

nfsd4: probe callback channel only once

Our callback code doesn't actually handle concurrent attempts to probe
the callback channel.  Some rethinking of the locking may be required.
However, we can also just move the callback probing to this case.  Since
this is the only time a client is "confirmed" (and since that can only
happen once in the lifetime of a client), this ensures we only probe
once.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
---

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 9d536a8cb3..a9735a6729 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -395,8 +395,7 @@ nfsd4_probe_callback(struct nfs4_client *clp)
 	};
 	struct task_struct *t;
 
-	if (atomic_read(&cb->cb_set))
-		return;
+	BUG_ON(atomic_read(&clp->cl_callback.cb_set));
 
 	/* Initialize address */
 	memset(&addr, 0, sizeof(addr));
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 31673cd251..9d81c7117a 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -948,6 +948,7 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
 			}
 			move_to_confirmed(unconf);
 			conf = unconf;
+			nfsd4_probe_callback(conf);
 			status = nfs_ok;
 		}
 	} else if ((!conf || (conf && !same_verf(&conf->cl_confirm, &confirm)))
@@ -965,8 +966,6 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
 		status = nfserr_clid_inuse;
 	}
 out:
-	if (!status)
-		nfsd4_probe_callback(conf);
 	nfs4_unlock_state();
 	return status;
 }