SUNRPC: make SUNPRC clients list per network namespace context

This patch moves static SUNRPC clients list and it's lock to sunrpc_net
structure.
Currently this list is used only for debug purposes. But later it will be used
also for selecting clients by networks namespace on PipeFS mount/umount events.
Per-network namespace lists will make this faster and simplier.

Note: client list is taken from "init_net" network namespace context in
rpc_show_tasks(). This will be changed some day later with making SUNRPC
sysctl's per network namespace context.

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

4 files changed, 24 insertions, 12 deletions

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 5ef192c1a57c..90e82c5daeb6 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -38,6 +38,7 @@
 #include <linux/sunrpc/bc_xprt.h>
 
 #include "sunrpc.h"
+#include "netns.h"
 
 #ifdef RPC_DEBUG
 # define RPCDBG_FACILITY        RPCDBG_CALL
@@ -50,8 +51,6 @@
 /*
  * All RPC clients are linked into this list
  */
-static LIST_HEAD(all_clients);
-static DEFINE_SPINLOCK(rpc_client_lock);
 
 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
 
@@ -81,16 +80,20 @@ static int	rpc_ping(struct rpc_clnt *clnt);
 
 static void rpc_register_client(struct rpc_clnt *clnt)
 {
-        spin_lock(&rpc_client_lock);
-        list_add(&clnt->cl_clients, &all_clients);
-        spin_unlock(&rpc_client_lock);
+        struct sunrpc_net *sn = net_generic(clnt->cl_xprt->xprt_net, sunrpc_net_id);
+
+        spin_lock(&sn->rpc_client_lock);
+        list_add(&clnt->cl_clients, &sn->all_clients);
+        spin_unlock(&sn->rpc_client_lock);
 }
 
 static void rpc_unregister_client(struct rpc_clnt *clnt)
 {
-        spin_lock(&rpc_client_lock);
+        struct sunrpc_net *sn = net_generic(clnt->cl_xprt->xprt_net, sunrpc_net_id);
+
+        spin_lock(&sn->rpc_client_lock);
         list_del(&clnt->cl_clients);
-        spin_unlock(&rpc_client_lock);
+        spin_unlock(&sn->rpc_client_lock);
 }
 
 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
@@ -1883,14 +1886,15 @@ static void rpc_show_task(const struct rpc_clnt *clnt,
                 task->tk_action, rpc_waitq);
 }
 
-void rpc_show_tasks(void)
+void rpc_show_tasks(struct net *net)
 {
         struct rpc_clnt *clnt;
         struct rpc_task *task;
         int header = 0;
+        struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 
-        spin_lock(&rpc_client_lock);
-        list_for_each_entry(clnt, &all_clients, cl_clients) {
+        spin_lock(&sn->rpc_client_lock);
+        list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
                 spin_lock(&clnt->cl_lock);
                 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
                         if (!header) {
@@ -1901,6 +1905,6 @@ void rpc_show_tasks(void)
                 }
                 spin_unlock(&clnt->cl_lock);
         }
-        spin_unlock(&rpc_client_lock);
+        spin_unlock(&sn->rpc_client_lock);
 }
 #endif
diff --git a/net/sunrpc/netns.h b/net/sunrpc/netns.h
index 11d2f4863403..0f3af34fa502 100644
--- a/net/sunrpc/netns.h
+++ b/net/sunrpc/netns.h
@@ -12,6 +12,9 @@ struct sunrpc_net {
 
         struct super_block *pipefs_sb;
         struct mutex pipefs_sb_lock;
+
+        struct list_head all_clients;
+        spinlock_t rpc_client_lock;
 };
 
 extern int sunrpc_net_id;
diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c
index 7086d11589c8..b4217dc8599c 100644
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -29,6 +29,7 @@ int sunrpc_net_id;
 static __net_init int sunrpc_init_net(struct net *net)
 {
         int err;
+        struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 
         err = rpc_proc_init(net);
         if (err)
@@ -39,6 +40,8 @@ static __net_init int sunrpc_init_net(struct net *net)
                 goto err_ipmap;
 
         rpc_pipefs_init_net(net);
+        INIT_LIST_HEAD(&sn->all_clients);
+        spin_lock_init(&sn->rpc_client_lock);
         return 0;
 
 err_ipmap:
diff --git a/net/sunrpc/sysctl.c b/net/sunrpc/sysctl.c
index e65dcc613339..af7d339add9d 100644
--- a/net/sunrpc/sysctl.c
+++ b/net/sunrpc/sysctl.c
@@ -20,6 +20,8 @@
 #include <linux/sunrpc/stats.h>
 #include <linux/sunrpc/svc_xprt.h>
 
+#include "netns.h"
+
 /*
  * Declare the debug flags here
  */
@@ -110,7 +112,7 @@ proc_dodebug(ctl_table *table, int write,
                 *(unsigned int *) table->data = value;
                 /* Display the RPC tasks on writing to rpc_debug */
                 if (strcmp(table->procname, "rpc_debug") == 0)
-                        rpc_show_tasks();
+                        rpc_show_tasks(&init_net);
         } else {
                 if (!access_ok(VERIFY_WRITE, buffer, left))
                         return -EFAULT;