[PATCH v2 0/4] SUNRPC: service release in network namespace context

[PATCH v2 0/4] SUNRPC: service release in network namespace context

[Stanislav Kinsbursky]

v2: Added comment to BUG_ON's in svc_destroy() to make code looks clearer.

This patch set is the final step towards to making LockD network namespace
aware.
I can't prove, that this patch set is enough for NFSd (just haven't try), by
Lockd works fine and patches for it will be send soon.

The following series consists of:

---

Stanislav Kinsbursky (4):
      SUNRPC: clear svc pools lists helper introduced
      SUNRPC: clear svc transports lists helper introduced
      SUNRPC: service destruction in network namespace context
      SUNRPC: service shutdown function in network namespace context introduced


 include/linux/sunrpc/svcsock.h |    2 +-
 net/sunrpc/svc.c               |   38 ++++++++++++++++++++++++----------
 net/sunrpc/svc_xprt.c          |   45 ++++++++++++++++++++++++++++------------
 3 files changed, 59 insertions(+), 26 deletions(-)

[PATCH v2 1/4] SUNRPC: clear svc pools lists helper introduced

[Stanislav Kinsbursky]

This patch moves removing of service transport from it's pools ready lists to
separated function. Also this clear is now done with list_for_each_entry_safe()
helper.
This is a precursor patch, which would be usefull with service shutdown in
network namespace context, introduced later in the series.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

---
 net/sunrpc/svc_xprt.c |   19 +++++++++++++------
 1 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index de1e1a8..50bf7c1 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -932,26 +932,33 @@ static void svc_close_list(struct list_head *xprt_list)
 	}
 }
 
-void svc_close_all(struct svc_serv *serv)
+static void svc_clear_pools(struct svc_serv *serv)
 {
 	struct svc_pool *pool;
 	struct svc_xprt *xprt;
 	struct svc_xprt *tmp;
 	int i;
 
-	svc_close_list(&serv->sv_tempsocks);
-	svc_close_list(&serv->sv_permsocks);
-
 	for (i = 0; i < serv->sv_nrpools; i++) {
 		pool = &serv->sv_pools[i];
 
 		spin_lock_bh(&pool->sp_lock);
-		while (!list_empty(&pool->sp_sockets)) {
-			xprt = list_first_entry(&pool->sp_sockets, struct svc_xprt, xpt_ready);
+		list_for_each_entry_safe(xprt, tmp, &pool->sp_sockets, xpt_ready) {
 			list_del_init(&xprt->xpt_ready);
 		}
 		spin_unlock_bh(&pool->sp_lock);
 	}
+}
+
+void svc_close_all(struct svc_serv *serv)
+{
+	struct svc_xprt *xprt;
+	struct svc_xprt *tmp;
+
+	svc_close_list(&serv->sv_tempsocks);
+	svc_close_list(&serv->sv_permsocks);
+
+	svc_clear_pools(serv);
 	/*
 	 * At this point the sp_sockets lists will stay empty, since
 	 * svc_enqueue will not add new entries without taking the

[PATCH v2 2/4] SUNRPC: clear svc transports lists helper introduced

[Stanislav Kinsbursky]

This patch moves service transports deletion from service sockets lists to
separated function.
This is a precursor patch, which would be usefull with service shutdown in
network namespace context, introduced later in the series.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

---
 net/sunrpc/svc_xprt.c |   19 +++++++++++--------
 1 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 50bf7c1..493e70b 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -950,11 +950,19 @@ static void svc_clear_pools(struct svc_serv *serv)
 	}
 }
 
-void svc_close_all(struct svc_serv *serv)
+static void svc_clear_list(struct list_head *xprt_list)
 {
 	struct svc_xprt *xprt;
 	struct svc_xprt *tmp;
 
+	list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) {
+		svc_delete_xprt(xprt);
+	}
+	BUG_ON(!list_empty(xprt_list));
+}
+
+void svc_close_all(struct svc_serv *serv)
+{
 	svc_close_list(&serv->sv_tempsocks);
 	svc_close_list(&serv->sv_permsocks);
 
@@ -964,13 +972,8 @@ void svc_close_all(struct svc_serv *serv)
 	 * svc_enqueue will not add new entries without taking the
 	 * sp_lock and checking XPT_BUSY.
 	 */
-	list_for_each_entry_safe(xprt, tmp, &serv->sv_tempsocks, xpt_list)
-		svc_delete_xprt(xprt);
-	list_for_each_entry_safe(xprt, tmp, &serv->sv_permsocks, xpt_list)
-		svc_delete_xprt(xprt);
-
-	BUG_ON(!list_empty(&serv->sv_permsocks));
-	BUG_ON(!list_empty(&serv->sv_tempsocks));
+	svc_clear_list(&serv->sv_tempsocks);
+	svc_clear_list(&serv->sv_permsocks);
 }
 
 /*

[PATCH v2 3/4] SUNRPC: service destruction in network namespace context

[Stanislav Kinsbursky]

v2: Added comment to BUG_ON's in svc_destroy() to make code looks clearer.

This patch introduces network namespace filter for service destruction
function.
Nothing special here - just do exactly the same operations, but only for
tranports in passed networks namespace context.
BTW, BUG_ON() checks for empty service transports lists were returned into
svc_destroy() function. This is because of swithing generic svc_close_all() to
networks namespace dependable svc_close_net().

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

---
 include/linux/sunrpc/svcsock.h |    2 +-
 net/sunrpc/svc.c               |   13 +++++++++++--
 net/sunrpc/svc_xprt.c          |   27 +++++++++++++++++----------
 3 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h
index c84e974..cb4ac69 100644
--- a/include/linux/sunrpc/svcsock.h
+++ b/include/linux/sunrpc/svcsock.h
@@ -34,7 +34,7 @@ struct svc_sock {
 /*
  * Function prototypes.
  */
-void		svc_close_all(struct svc_serv *);
+void		svc_close_net(struct svc_serv *, struct net *);
 int		svc_recv(struct svc_rqst *, long);
 int		svc_send(struct svc_rqst *);
 void		svc_drop(struct svc_rqst *);
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index a8b49a0..6cc0ea3 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -517,6 +517,8 @@ EXPORT_SYMBOL_GPL(svc_create_pooled);
 void
 svc_destroy(struct svc_serv *serv)
 {
+	struct net *net = current->nsproxy->net_ns;
+
 	dprintk("svc: svc_destroy(%s, %d)\n",
 				serv->sv_program->pg_name,
 				serv->sv_nrthreads);
@@ -539,10 +541,17 @@ svc_destroy(struct svc_serv *serv)
 	 * caller is using--nfsd_mutex in the case of nfsd).  So it's
 	 * safe to traverse those lists and shut everything down:
 	 */
-	svc_close_all(serv);
+	svc_close_net(serv, net);
+
+	/*
+	 * The last user is gone and thus all sockets have to be destroyed to
+	 * the point. Check this.
+	 */
+	BUG_ON(!list_empty(&serv->sv_permsocks));
+	BUG_ON(!list_empty(&serv->sv_tempsocks));
 
 	if (serv->sv_shutdown)
-		serv->sv_shutdown(serv, current->nsproxy->net_ns);
+		serv->sv_shutdown(serv, net);
 
 	cache_clean_deferred(serv);
 
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 493e70b..4bda09d 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -922,17 +922,19 @@ void svc_close_xprt(struct svc_xprt *xprt)
 }
 EXPORT_SYMBOL_GPL(svc_close_xprt);
 
-static void svc_close_list(struct list_head *xprt_list)
+static void svc_close_list(struct list_head *xprt_list, struct net *net)
 {
 	struct svc_xprt *xprt;
 
 	list_for_each_entry(xprt, xprt_list, xpt_list) {
+		if (xprt->xpt_net != net)
+			continue;
 		set_bit(XPT_CLOSE, &xprt->xpt_flags);
 		set_bit(XPT_BUSY, &xprt->xpt_flags);
 	}
 }
 
-static void svc_clear_pools(struct svc_serv *serv)
+static void svc_clear_pools(struct svc_serv *serv, struct net *net)
 {
 	struct svc_pool *pool;
 	struct svc_xprt *xprt;
@@ -944,36 +946,41 @@ static void svc_clear_pools(struct svc_serv *serv)
 
 		spin_lock_bh(&pool->sp_lock);
 		list_for_each_entry_safe(xprt, tmp, &pool->sp_sockets, xpt_ready) {
+			if (xprt->xpt_net != net)
+				continue;
 			list_del_init(&xprt->xpt_ready);
 		}
 		spin_unlock_bh(&pool->sp_lock);
 	}
 }
 
-static void svc_clear_list(struct list_head *xprt_list)
+static void svc_clear_list(struct list_head *xprt_list, struct net *net)
 {
 	struct svc_xprt *xprt;
 	struct svc_xprt *tmp;
 
 	list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) {
+		if (xprt->xpt_net != net)
+			continue;
 		svc_delete_xprt(xprt);
 	}
-	BUG_ON(!list_empty(xprt_list));
+	list_for_each_entry(xprt, xprt_list, xpt_list)
+		BUG_ON(xprt->xpt_net == net);
 }
 
-void svc_close_all(struct svc_serv *serv)
+void svc_close_net(struct svc_serv *serv, struct net *net)
 {
-	svc_close_list(&serv->sv_tempsocks);
-	svc_close_list(&serv->sv_permsocks);
+	svc_close_list(&serv->sv_tempsocks, net);
+	svc_close_list(&serv->sv_permsocks, net);
 
-	svc_clear_pools(serv);
+	svc_clear_pools(serv, net);
 	/*
 	 * At this point the sp_sockets lists will stay empty, since
 	 * svc_enqueue will not add new entries without taking the
 	 * sp_lock and checking XPT_BUSY.
 	 */
-	svc_clear_list(&serv->sv_tempsocks);
-	svc_clear_list(&serv->sv_permsocks);
+	svc_clear_list(&serv->sv_tempsocks, net);
+	svc_clear_list(&serv->sv_permsocks, net);
 }
 
 /*

[PATCH v2 4/4] SUNRPC: service shutdown function in network namespace context introduced

[Stanislav Kinsbursky]

This function is enough for releasing resources, allocated for network
namespace context, in case of sharing service between them.
IOW, each service "user" (LockD, NFSd, etc), which wants to share service
between network namespaces, have to release related resources by the function,
introduced in this patch, instead of performing service shutdown (of course in
case the service is shared already to the moment of release).

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

---
 net/sunrpc/svc.c |   33 ++++++++++++++++++++-------------
 1 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 6cc0ea3..78abac4 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -510,6 +510,24 @@ svc_create_pooled(struct svc_program *prog, unsigned int bufsize,
 }
 EXPORT_SYMBOL_GPL(svc_create_pooled);
 
+void svc_shutdown_net(struct svc_serv *serv, struct net *net)
+{
+	/*
+	 * The set of xprts (contained in the sv_tempsocks and
+	 * sv_permsocks lists) is now constant, since it is modified
+	 * only by accepting new sockets (done by service threads in
+	 * svc_recv) or aging old ones (done by sv_temptimer), or
+	 * configuration changes (excluded by whatever locking the
+	 * caller is using--nfsd_mutex in the case of nfsd).  So it's
+	 * safe to traverse those lists and shut everything down:
+	 */
+	svc_close_net(serv, net);
+
+	if (serv->sv_shutdown)
+		serv->sv_shutdown(serv, net);
+}
+EXPORT_SYMBOL_GPL(svc_shutdown_net);
+
 /*
  * Destroy an RPC service. Should be called with appropriate locking to
  * protect the sv_nrthreads, sv_permsocks and sv_tempsocks.
@@ -532,16 +550,8 @@ svc_destroy(struct svc_serv *serv)
 		printk("svc_destroy: no threads for serv=%p!\n", serv);
 
 	del_timer_sync(&serv->sv_temptimer);
-	/*
-	 * The set of xprts (contained in the sv_tempsocks and
-	 * sv_permsocks lists) is now constant, since it is modified
-	 * only by accepting new sockets (done by service threads in
-	 * svc_recv) or aging old ones (done by sv_temptimer), or
-	 * configuration changes (excluded by whatever locking the
-	 * caller is using--nfsd_mutex in the case of nfsd).  So it's
-	 * safe to traverse those lists and shut everything down:
-	 */
-	svc_close_net(serv, net);
+
+	svc_shutdown_net(serv, net);
 
 	/*
 	 * The last user is gone and thus all sockets have to be destroyed to
@@ -550,9 +560,6 @@ svc_destroy(struct svc_serv *serv)
 	BUG_ON(!list_empty(&serv->sv_permsocks));
 	BUG_ON(!list_empty(&serv->sv_tempsocks));
 
-	if (serv->sv_shutdown)
-		serv->sv_shutdown(serv, net);
-
 	cache_clean_deferred(serv);
 
 	if (svc_serv_is_pooled(serv))