svc: Add svc API that queries for a transport instance
Add a new svc function that allows a service to query whether a
transport instance has already been created. This is used in lockd
to determine whether or not a transport needs to be created when
a lockd instance is brought up.
Specifying 0 for the address family or port is effectively a wild-card,
and will result in matching the first transport in the service's list
that has a matching class name.
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>
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index a8e79a9..470af01 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -219,18 +219,6 @@
module_put_and_exit(0);
}
-static int find_xprt(struct svc_serv *serv, char *proto)
-{
- struct svc_xprt *xprt;
- int found = 0;
- list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list)
- if (strcmp(xprt->xpt_class->xcl_name, proto) == 0) {
- found = 1;
- break;
- }
- return found;
-}
-
/*
* Make any sockets that are needed but not present.
* If nlm_udpport or nlm_tcpport were set as module
@@ -242,11 +230,11 @@
int err = 0;
if (proto == IPPROTO_UDP || nlm_udpport)
- if (!find_xprt(serv, "udp"))
+ if (!svc_find_xprt(serv, "udp", 0, 0))
err = svc_create_xprt(serv, "udp", nlm_udpport,
SVC_SOCK_DEFAULTS);
if (err >= 0 && (proto == IPPROTO_TCP || nlm_tcpport))
- if (!find_xprt(serv, "tcp"))
+ if (!svc_find_xprt(serv, "tcp", 0, 0))
err = svc_create_xprt(serv, "tcp", nlm_tcpport,
SVC_SOCK_DEFAULTS);
diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h
index 01e71b7..68862d5 100644
--- a/include/linux/sunrpc/svc_xprt.h
+++ b/include/linux/sunrpc/svc_xprt.h
@@ -80,6 +80,7 @@
void svc_delete_xprt(struct svc_xprt *xprt);
int svc_port_is_privileged(struct sockaddr *sin);
int svc_print_xprts(char *buf, int maxlen);
+struct svc_xprt *svc_find_xprt(struct svc_serv *, char *, int, int);
static inline void svc_xprt_get(struct svc_xprt *xprt)
{
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 2e5b92a..512c10f 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -977,3 +977,38 @@
spin_unlock(&xprt->xpt_lock);
return dr;
}
+
+/*
+ * Return the transport instance pointer for the endpoint accepting
+ * connections/peer traffic from the specified transport class,
+ * address family and port.
+ *
+ * Specifying 0 for the address family or port is effectively a
+ * wild-card, and will result in matching the first transport in the
+ * service's list that has a matching class name.
+ */
+struct svc_xprt *svc_find_xprt(struct svc_serv *serv, char *xcl_name,
+ int af, int port)
+{
+ struct svc_xprt *xprt;
+ struct svc_xprt *found = NULL;
+
+ /* Sanity check the args */
+ if (!serv || !xcl_name)
+ return found;
+
+ spin_lock_bh(&serv->sv_lock);
+ list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) {
+ if (strcmp(xprt->xpt_class->xcl_name, xcl_name))
+ continue;
+ if (af != AF_UNSPEC && af != xprt->xpt_local.ss_family)
+ continue;
+ if (port && port != svc_xprt_local_port(xprt))
+ continue;
+ found = xprt;
+ break;
+ }
+ spin_unlock_bh(&serv->sv_lock);
+ return found;
+}
+EXPORT_SYMBOL_GPL(svc_find_xprt);
