nfsd: provide callbacks on svc_xprt deletion
NFSv4.1 needs warning when a client tcp connection goes down, if that
connection is being used as a backchannel, so that it can warn the
client that it has lost the backchannel connection.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 678b6ee..12025ee 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -156,6 +156,7 @@
INIT_LIST_HEAD(&xprt->xpt_list);
INIT_LIST_HEAD(&xprt->xpt_ready);
INIT_LIST_HEAD(&xprt->xpt_deferred);
+ INIT_LIST_HEAD(&xprt->xpt_users);
mutex_init(&xprt->xpt_mutex);
spin_lock_init(&xprt->xpt_lock);
set_bit(XPT_BUSY, &xprt->xpt_flags);
@@ -881,6 +882,19 @@
mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ);
}
+static void call_xpt_users(struct svc_xprt *xprt)
+{
+ struct svc_xpt_user *u;
+
+ spin_lock(&xprt->xpt_lock);
+ while (!list_empty(&xprt->xpt_users)) {
+ u = list_first_entry(&xprt->xpt_users, struct svc_xpt_user, list);
+ list_del(&u->list);
+ u->callback(u);
+ }
+ spin_unlock(&xprt->xpt_lock);
+}
+
/*
* Remove a dead transport
*/
@@ -913,6 +927,7 @@
while ((dr = svc_deferred_dequeue(xprt)) != NULL)
kfree(dr);
+ call_xpt_users(xprt);
svc_xprt_put(xprt);
}