[PATCH] lockdep: annotate nfs/nfsd in-kernel sockets

Stick NFS sockets in their own class to avoid some lockdep warnings.  NFS
sockets are never exposed to user-space, and will hence not trigger certain
code paths that would otherwise pose deadlock scenarios.

[akpm@osdl.org: cleanups]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Dickson <SteveD@redhat.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: Neil Brown <neilb@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
[ Fixed patch corruption by quilt, pointed out by Peter Zijlstra ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 31 insertions, 0 deletions

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index cfe3c15be948..2fc4a3123261 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1058,6 +1058,35 @@ static int xs_bindresvport(struct rpc_xprt *xprt, struct socket *sock)
         return err;
 }
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static struct lock_class_key xs_key[2];
+static struct lock_class_key xs_slock_key[2];
+
+static inline void xs_reclassify_socket(struct socket *sock)
+{
+        struct sock *sk = sock->sk;
+        BUG_ON(sk->sk_lock.owner != NULL);
+        switch (sk->sk_family) {
+        case AF_INET:
+                sock_lock_init_class_and_name(sk, "slock-AF_INET-NFS",
+                        &xs_slock_key[0], "sk_lock-AF_INET-NFS", &xs_key[0]);
+                break;
+
+        case AF_INET6:
+                sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFS",
+                        &xs_slock_key[1], "sk_lock-AF_INET6-NFS", &xs_key[1]);
+                break;
+
+        default:
+                BUG();
+        }
+}
+#else
+static inline void xs_reclassify_socket(struct socket *sock)
+{
+}
+#endif
+
 /**
  * xs_udp_connect_worker - set up a UDP socket
  * @work: RPC transport to connect
@@ -1081,6 +1110,7 @@ static void xs_udp_connect_worker(struct work_struct *work)
                 dprintk("RPC:      can't create UDP transport socket (%d).\n", -err);
                 goto out;
         }
+        xs_reclassify_socket(sock);
 
         if (xprt->resvport && xs_bindresvport(xprt, sock) < 0) {
                 sock_release(sock);
@@ -1165,6 +1195,7 @@ static void xs_tcp_connect_worker(struct work_struct *work)
                         dprintk("RPC:      can't create TCP transport socket (%d).\n", -err);
                         goto out;
                 }
+                xs_reclassify_socket(sock);
 
                 if (xprt->resvport && xs_bindresvport(xprt, sock) < 0) {
                         sock_release(sock);