[PATCH] NFS: Fix NFSv4 callback regression

The change in semantics for nfs_find_client() introduced by David breaks the
NFSv4 callback channel.

Also, replace another completely broken BUG_ON() in nfs_find_client().  In
initialised clients, clp->cl_cons_state == 0, and callers of that function
should in any case never want to see clients that are uninitialised.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 8b123f6a7d0297d6934471c8ca98a56ea299342b..5fea638743e4107aadcd8cbd18cd46d78e331cf0 100644 (file)
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -232,11 +232,15 @@ void nfs_put_client(struct nfs_client *clp)
  * Find a client by address
  * - caller must hold nfs_client_lock
  */
-static struct nfs_client *__nfs_find_client(const struct sockaddr_in *addr, int nfsversion)
+static struct nfs_client *__nfs_find_client(const struct sockaddr_in *addr, int nfsversion, int match_port)
 {
        struct nfs_client *clp;
 
        list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
+               /* Don't match clients that failed to initialise properly */
+               if (clp->cl_cons_state < 0)
+                       continue;
+
                /* Different NFS versions cannot share the same nfs_client */
                if (clp->cl_nfsversion != nfsversion)
                        continue;
@@ -245,7 +249,7 @@ static struct nfs_client *__nfs_find_client(const struct sockaddr_in *addr, int
                           sizeof(clp->cl_addr.sin_addr)) != 0)
                        continue;
 
-               if (clp->cl_addr.sin_port == addr->sin_port)
+               if (!match_port || clp->cl_addr.sin_port == addr->sin_port)
                        goto found;
        }
 
@@ -265,11 +269,12 @@ struct nfs_client *nfs_find_client(const struct sockaddr_in *addr, int nfsversio
        struct nfs_client *clp;
 
        spin_lock(&nfs_client_lock);
-       clp = __nfs_find_client(addr, nfsversion);
+       clp = __nfs_find_client(addr, nfsversion, 0);
        spin_unlock(&nfs_client_lock);
-
-       BUG_ON(clp && clp->cl_cons_state == 0);
-
+       if (clp != NULL && clp->cl_cons_state != NFS_CS_READY) {
+               nfs_put_client(clp);
+               clp = NULL;
+       }
        return clp;
 }
 
@@ -292,7 +297,7 @@ static struct nfs_client *nfs_get_client(const char *hostname,
        do {
                spin_lock(&nfs_client_lock);
 
-               clp = __nfs_find_client(addr, nfsversion);
+               clp = __nfs_find_client(addr, nfsversion, 1);
                if (clp)
                        goto found_client;
                if (new)