[Devel] [PATCH 04/11] SUNRPC: per-net sysctl's set introduced

[Stanislav Kinsbursky]

This patch introduces per-net sysctl set and it's initialization routines. Also
it modifies sysctl's registering helpers to make them use these sets.

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

---
 include/linux/sunrpc/debug.h    |    7 ++++++-
 net/sunrpc/netns.h              |    3 +++
 net/sunrpc/sunrpc_syms.c        |   13 ++++++++++++-
 net/sunrpc/sysctl.c             |   38 +++++++++++++++++++++++++++++++++-----
 net/sunrpc/xprtrdma/transport.c |    2 +-
 net/sunrpc/xprtsock.c           |    2 +-
 6 files changed, 56 insertions(+), 9 deletions(-)

diff --git a/include/linux/sunrpc/debug.h b/include/linux/sunrpc/debug.h
index b5e0c46..f2d825c 100644
--- a/include/linux/sunrpc/debug.h
+++ b/include/linux/sunrpc/debug.h
@@ -67,7 +67,12 @@ extern unsigned int		nlm_debug;
 void		rpc_register_sysctl(void);
 void		rpc_unregister_sysctl(void);
 
-struct ctl_table_header *register_sunrpc_sysctl(struct ctl_table *);
+struct net;
+struct ctl_table;
+int debug_sysctl_init(struct net *);
+void debug_sysctl_exit(struct net *);
+struct ctl_table_header *register_sunrpc_sysctl(struct net *,
+						struct ctl_table *);
 
 #endif
 
diff --git a/net/sunrpc/netns.h b/net/sunrpc/netns.h
index 6010c46..a949ddb 100644
--- a/net/sunrpc/netns.h
+++ b/net/sunrpc/netns.h
@@ -12,6 +12,9 @@ struct sunrpc_net {
 
 	struct list_head all_clients;
 	spinlock_t rpc_client_lock;
+#ifdef RPC_DEBUG
+	struct ctl_table_set sysctls;
+#endif
 };
 
 extern int sunrpc_net_id;
diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c
index e57aa10..44759e9 100644
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -38,11 +38,19 @@ static __net_init int sunrpc_init_net(struct net *net)
 	err = ip_map_cache_create(net);
 	if (err)
 		goto err_ipmap;
-
+#ifdef RPC_DEBUG
+	err = debug_sysctl_init(net);
+	if (err)
+		goto err_sysctl;
+#endif
 	INIT_LIST_HEAD(&sn->all_clients);
 	spin_lock_init(&sn->rpc_client_lock);
 	return 0;
 
+#ifdef RPC_DEBUG
+err_sysctl:
+	ip_map_cache_destroy(net);
+#endif
 err_ipmap:
 	rpc_proc_exit(net);
 err_proc:
@@ -51,6 +59,9 @@ err_proc:
 
 static __net_exit void sunrpc_exit_net(struct net *net)
 {
+#ifdef RPC_DEBUG
+	debug_sysctl_exit(net);
+#endif
 	ip_map_cache_destroy(net);
 	rpc_proc_exit(net);
 }
diff --git a/net/sunrpc/sysctl.c b/net/sunrpc/sysctl.c
index f6e7da2..adebf0a 100644
--- a/net/sunrpc/sysctl.c
+++ b/net/sunrpc/sysctl.c
@@ -40,7 +40,7 @@ EXPORT_SYMBOL_GPL(nlm_debug);
 #ifdef RPC_DEBUG
 
 #include <linux/nsproxy.h>
-#include <net/net_namespace.h>
+#include "netns.h"
 
 static struct ctl_table_header *sunrpc_table_header;
 static ctl_table		debug_table[];
@@ -50,23 +50,51 @@ struct ctl_path sunrpc_path[] = {
 	{ },
 };
 
+static struct ctl_table_set *
+sunrpc_debug_lookup(struct ctl_table_root *root, struct nsproxy *namespaces)
+{
+	struct sunrpc_net *sn = net_generic(namespaces->net_ns, sunrpc_net_id);
+
+	return &sn->sysctls;
+}
+
 static struct ctl_table_root sunrpc_debug_root = {
+	.lookup	= sunrpc_debug_lookup,
 };
 
-struct ctl_table_header *register_sunrpc_sysctl(struct ctl_table *table)
+struct ctl_table_header *register_sunrpc_sysctl(struct net *net,
+						struct ctl_table *table)
 {
-	return __register_sysctl_paths(&sunrpc_debug_root, current->nsproxy,
+	struct nsproxy namespaces;
+
+	namespaces = *current->nsproxy;
+	namespaces.net_ns = net;
+	return __register_sysctl_paths(&sunrpc_debug_root, &namespaces,
 				       sunrpc_path, table);
 }
 EXPORT_SYMBOL_GPL(register_sunrpc_sysctl);
 
+int debug_sysctl_init(struct net *net)
+{
+	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+
+	setup_sysctl_set(&sn->sysctls, NULL, NULL);
+	return 0;
+}
+
+void debug_sysctl_exit(struct net *net)
+{
+	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+
+	WARN_ON(!list_empty(&sn->sysctls.list));
+}
+
 void
 rpc_register_sysctl(void)
 {
 	if (!sunrpc_table_header) {
-		setup_sysctl_set(&sunrpc_debug_root.default_set, NULL, NULL);
 		register_sysctl_root(&sunrpc_debug_root);
-		sunrpc_table_header = register_sunrpc_sysctl(debug_table);
+		sunrpc_table_header = register_sunrpc_sysctl(&init_net, debug_table);
 	}
 }
 
diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c
index 53a8622..4a63b35 100644
--- a/net/sunrpc/xprtrdma/transport.c
+++ b/net/sunrpc/xprtrdma/transport.c
@@ -762,7 +762,7 @@ static int __init xprt_rdma_init(void)
 
 #ifdef RPC_DEBUG
 	if (!sunrpc_table_header)
-		sunrpc_table_header = register_sunrpc_sysctl(xr_tunables_table);
+		sunrpc_table_header = register_sunrpc_sysctl(&init_net, xr_tunables_table);
 #endif
 	return 0;
 }
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 6f1be96..1acc9a7 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -2878,7 +2878,7 @@ int init_socket_xprt(void)
 {
 #ifdef RPC_DEBUG
 	if (!sunrpc_table_header)
-		sunrpc_table_header = register_sunrpc_sysctl(xs_tunables_table);
+		sunrpc_table_header = register_sunrpc_sysctl(&init_net, xs_tunables_table);
 #endif
 
 	xprt_register_transport(&xs_local_transport);