svc: Add per-transport delete functions

Add transport specific xpo_detach and xpo_free functions. The xpo_detach
function causes the transport to stop delivering data-ready events
and enqueing the transport for I/O.

The xpo_free function frees all resources associated with the particular
transport instance.

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

2 files changed, 45 insertions, 13 deletions

diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h
index 01ee7bc2c374..f032fb6b32e9 100644
--- a/include/linux/sunrpc/svc_xprt.h
+++ b/include/linux/sunrpc/svc_xprt.h
@@ -13,6 +13,8 @@ struct svc_xprt_ops {
         int             (*xpo_recvfrom)(struct svc_rqst *);
         int             (*xpo_sendto)(struct svc_rqst *);
         void            (*xpo_release_rqst)(struct svc_rqst *);
+        void            (*xpo_detach)(struct svc_xprt *);
+        void            (*xpo_free)(struct svc_xprt *);
 };
 
 struct svc_xprt_class {
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index d46abc89b99a..44a729d6efea 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -85,6 +85,8 @@ static void		svc_udp_data_ready(struct sock *, int);
 static int              svc_udp_recvfrom(struct svc_rqst *);
 static int              svc_udp_sendto(struct svc_rqst *);
 static void             svc_close_socket(struct svc_sock *svsk);
+static void             svc_sock_detach(struct svc_xprt *);
+static void             svc_sock_free(struct svc_xprt *);
 
 static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk);
 static int svc_deferred_recv(struct svc_rqst *rqstp);
@@ -376,16 +378,8 @@ static inline void
 svc_sock_put(struct svc_sock *svsk)
 {
         if (atomic_dec_and_test(&svsk->sk_inuse)) {
-                BUG_ON(! test_bit(SK_DEAD, &svsk->sk_flags));
-
-                dprintk("svc: releasing dead socket\n");
-                if (svsk->sk_sock->file)
-                        sockfd_put(svsk->sk_sock);
-                else
-                        sock_release(svsk->sk_sock);
-                if (svsk->sk_info_authunix != NULL)
-                        svcauth_unix_info_release(svsk->sk_info_authunix);
-                kfree(svsk);
+                BUG_ON(!test_bit(SK_DEAD, &svsk->sk_flags));
+                svsk->sk_xprt.xpt_ops->xpo_free(&svsk->sk_xprt);
         }
 }
 
@@ -903,6 +897,8 @@ static struct svc_xprt_ops svc_udp_ops = {
         .xpo_recvfrom = svc_udp_recvfrom,
         .xpo_sendto = svc_udp_sendto,
         .xpo_release_rqst = svc_release_skb,
+        .xpo_detach = svc_sock_detach,
+        .xpo_free = svc_sock_free,
 };
 
 static struct svc_xprt_class svc_udp_class = {
@@ -1358,6 +1354,8 @@ static struct svc_xprt_ops svc_tcp_ops = {
         .xpo_recvfrom = svc_tcp_recvfrom,
         .xpo_sendto = svc_tcp_sendto,
         .xpo_release_rqst = svc_release_skb,
+        .xpo_detach = svc_sock_detach,
+        .xpo_free = svc_sock_free,
 };
 
 static struct svc_xprt_class svc_tcp_class = {
@@ -1815,6 +1813,40 @@ bummer:
 }
 
 /*
+ * Detach the svc_sock from the socket so that no
+ * more callbacks occur.
+ */
+static void svc_sock_detach(struct svc_xprt *xprt)
+{
+        struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+        struct sock *sk = svsk->sk_sk;
+
+        dprintk("svc: svc_sock_detach(%p)\n", svsk);
+
+        /* put back the old socket callbacks */
+        sk->sk_state_change = svsk->sk_ostate;
+        sk->sk_data_ready = svsk->sk_odata;
+        sk->sk_write_space = svsk->sk_owspace;
+}
+
+/*
+ * Free the svc_sock's socket resources and the svc_sock itself.
+ */
+static void svc_sock_free(struct svc_xprt *xprt)
+{
+        struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+        dprintk("svc: svc_sock_free(%p)\n", svsk);
+
+        if (svsk->sk_info_authunix != NULL)
+                svcauth_unix_info_release(svsk->sk_info_authunix);
+        if (svsk->sk_sock->file)
+                sockfd_put(svsk->sk_sock);
+        else
+                sock_release(svsk->sk_sock);
+        kfree(svsk);
+}
+
+/*
  * Remove a dead socket
  */
 static void
@@ -1828,9 +1860,7 @@ svc_delete_socket(struct svc_sock *svsk)
         serv = svsk->sk_server;
         sk = svsk->sk_sk;
 
-        sk->sk_state_change = svsk->sk_ostate;
-        sk->sk_data_ready = svsk->sk_odata;
-        sk->sk_write_space = svsk->sk_owspace;
+        svsk->sk_xprt.xpt_ops->xpo_detach(&svsk->sk_xprt);
 
         spin_lock_bh(&serv->sv_lock);