[PATCH 0/5] SUNRPC: make rpcbind clients allocated and destroyed on dynamically

[PATCH 0/5] SUNRPC: make rpcbind clients allocated and destroyed on dynamically

[Stanislav Kinsbursky]

This patch is required for further RPC layer virtualization, because rpcbind
clients have to be per network namespace.
To achive this, we have to untie network namespace from rpcbind clients sockets.
The idea of this patch set is to make rpcbind clients non-static. I.e. rpcbind
clients will be created during first RPC service creation, and destroyed when
last RPC service is stopped.
With this patch set rpcbind clients can be virtualized easely.

The following series consists of:

---

Stanislav Kinsbursky (5):
      SUNRPC: introduce helpers for reference counted rpcbind clients
      SUNRPC: use reference count helpers
      SUNRPC: make RPC service dependable on rpcbind clients creation
      SUNRPC: remove rpcbind clients creation during service registring
      SUNRPC: remove rpcbind clients destruction on module cleanup


 include/linux/sunrpc/clnt.h |    2 +
 net/sunrpc/rpcb_clnt.c      |   86 ++++++++++++++++++++++++++++---------------
 net/sunrpc/sunrpc_syms.c    |    3 --
 net/sunrpc/svc.c            |    5 +++
 4 files changed, 63 insertions(+), 33 deletions(-)

-- 
Signature

[PATCH 1/5] SUNRPC: introduce helpers for reference counted rpcbind clients

[Stanislav Kinsbursky]

This helpers will be used for dynamical creation and destruction of rpcbind
clients.
Variable rpcb_users is actually a counter of lauched RPC services. If rpcbind
client has been created already, then we just increase rpcb_users.

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

---
 net/sunrpc/rpcb_clnt.c |   51 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 51 insertions(+), 0 deletions(-)

diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index e45d2fb..c84e6a3 100644
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -114,6 +114,9 @@ static struct rpc_program	rpcb_program;
 static struct rpc_clnt *	rpcb_local_clnt;
 static struct rpc_clnt *	rpcb_local_clnt4;
 
+DEFINE_SPINLOCK(rpcb_clnt_lock);
+unsigned int			rpcb_users;
+
 struct rpcbind_args {
 	struct rpc_xprt *	r_xprt;
 
@@ -161,6 +164,54 @@ static void rpcb_map_release(void *data)
 	kfree(map);
 }
 
+static int rpcb_get_local(void)
+{
+	spin_lock(&rpcb_clnt_lock);
+	if (rpcb_users)
+		rpcb_users++;
+	spin_unlock(&rpcb_clnt_lock);
+
+	return rpcb_users;
+}
+
+void rpcb_put_local(void)
+{
+	struct rpc_clnt *clnt = rpcb_local_clnt;
+	struct rpc_clnt *clnt4 = rpcb_local_clnt4;
+	int shutdown;
+
+	spin_lock(&rpcb_clnt_lock);
+	if (--rpcb_users == 0) {
+		rpcb_local_clnt = NULL;
+		rpcb_local_clnt4 = NULL;
+	}
+	shutdown = !rpcb_users;
+	spin_unlock(&rpcb_clnt_lock);
+
+	if (shutdown) {
+		/*
+		 * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister
+		 */
+		if (clnt4)
+			rpc_shutdown_client(clnt4);
+		if (clnt)
+			rpc_shutdown_client(clnt);
+	}
+	return;
+}
+
+static void rpcb_set_local(struct rpc_clnt *clnt, struct rpc_clnt *clnt4)
+{
+	/* Protected by rpcb_create_local_mutex */
+	rpcb_local_clnt = clnt;
+	rpcb_local_clnt4 = clnt4;
+	rpcb_users++;
+	dprintk("RPC:       created new rpcb local clients (rpcb_local_clnt: "
+			"0x%p, rpcb_local_clnt4: 0x%p)\n", rpcb_local_clnt,
+			rpcb_local_clnt4);
+
+}
+
 /*
  * Returns zero on success, otherwise a negative errno value
  * is returned.

[PATCH 2/5] SUNRPC: use reference count helpers

[Stanislav Kinsbursky]

All is simple: we just increase users conters if rpcbind clients are present
already. Otherwise we create new rpcbind clients and set users counter to 1.

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

---
 net/sunrpc/rpcb_clnt.c |   12 ++++--------
 1 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index c84e6a3..b4cc0f1 100644
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -256,9 +256,7 @@ static int rpcb_create_local_unix(void)
 		clnt4 = NULL;
 	}
 
-	/* Protected by rpcb_create_local_mutex */
-	rpcb_local_clnt = clnt;
-	rpcb_local_clnt4 = clnt4;
+	rpcb_set_local(clnt, clnt4);
 
 out:
 	return result;
@@ -310,9 +308,7 @@ static int rpcb_create_local_net(void)
 		clnt4 = NULL;
 	}
 
-	/* Protected by rpcb_create_local_mutex */
-	rpcb_local_clnt = clnt;
-	rpcb_local_clnt4 = clnt4;
+	rpcb_set_local(clnt, clnt4);
 
 out:
 	return result;
@@ -327,11 +323,11 @@ static int rpcb_create_local(void)
 	static DEFINE_MUTEX(rpcb_create_local_mutex);
 	int result = 0;
 
-	if (rpcb_local_clnt)
+	if (rpcb_get_local())
 		return result;
 
 	mutex_lock(&rpcb_create_local_mutex);
-	if (rpcb_local_clnt)
+	if (rpcb_get_local())
 		goto out;
 
 	if (rpcb_create_local_unix() != 0)

[PATCH 3/5] SUNRPC: make RPC service dependable on rpcbind clients creation

[Stanislav Kinsbursky]

We create or increase users counter of rcbind clients during RPC service
creation and decrease this counter (and possibly destroy those clients) on RPC
service destruction.

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

---
 include/linux/sunrpc/clnt.h |    2 ++
 net/sunrpc/rpcb_clnt.c      |    2 +-
 net/sunrpc/svc.c            |    5 +++++
 3 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index db7bcaf..65a8115 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -135,10 +135,12 @@ void		rpc_shutdown_client(struct rpc_clnt *);
 void		rpc_release_client(struct rpc_clnt *);
 void		rpc_task_release_client(struct rpc_task *);
 
+int		rpcb_create_local(void);
 int		rpcb_register(u32, u32, int, unsigned short);
 int		rpcb_v4_register(const u32 program, const u32 version,
 				 const struct sockaddr *address,
 				 const char *netid);
+void		rpcb_put_local(void);
 void		rpcb_getport_async(struct rpc_task *);
 
 void		rpc_call_start(struct rpc_task *);
diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index b4cc0f1..437ec60 100644
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -318,7 +318,7 @@ out:
  * Returns zero on success, otherwise a negative errno value
  * is returned.
  */
-static int rpcb_create_local(void)
+int rpcb_create_local(void)
 {
 	static DEFINE_MUTEX(rpcb_create_local_mutex);
 	int result = 0;
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 6a69a11..0df8532 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -367,6 +367,9 @@ __svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
 	unsigned int xdrsize;
 	unsigned int i;
 
+	if (rpcb_create_local() < 0)
+		return NULL;
+
 	if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL)))
 		return NULL;
 	serv->sv_name      = prog->pg_name;
@@ -491,6 +494,8 @@ svc_destroy(struct svc_serv *serv)
 	svc_unregister(serv);
 	kfree(serv->sv_pools);
 	kfree(serv);
+
+	rpcb_put_local();
 }
 EXPORT_SYMBOL_GPL(svc_destroy);
 

[PATCH 4/5] SUNRPC: remove rpcbind clients creation during service registring

[Stanislav Kinsbursky]

We don't need this code since rpcbind clients are creating during RPC service
creation.

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

---
 net/sunrpc/rpcb_clnt.c |    9 ---------
 1 files changed, 0 insertions(+), 9 deletions(-)

diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index 437ec60..f363efe 100644
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -429,11 +429,6 @@ int rpcb_register(u32 prog, u32 vers, int prot, unsigned short port)
 	struct rpc_message msg = {
 		.rpc_argp	= &map,
 	};
-	int error;
-
-	error = rpcb_create_local();
-	if (error)
-		return error;
 
 	dprintk("RPC:       %sregistering (%u, %u, %d, %u) with local "
 			"rpcbind\n", (port ? "" : "un"),
@@ -569,11 +564,7 @@ int rpcb_v4_register(const u32 program, const u32 version,
 	struct rpc_message msg = {
 		.rpc_argp	= &map,
 	};
-	int error;
 
-	error = rpcb_create_local();
-	if (error)
-		return error;
 	if (rpcb_local_clnt4 == NULL)
 		return -EPROTONOSUPPORT;
 

[PATCH 5/5] SUNRPC: remove rpcbind clients destruction on module cleanup

[Stanislav Kinsbursky]

We don't need this anymore since now rpcbind clients are destroying during last
RPC service shutdown.

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

---
 net/sunrpc/rpcb_clnt.c   |   12 ------------
 net/sunrpc/sunrpc_syms.c |    3 ---
 2 files changed, 0 insertions(+), 15 deletions(-)

diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index f363efe..94a310d 100644
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -1098,15 +1098,3 @@ static struct rpc_program rpcb_program = {
 	.version	= rpcb_version,
 	.stats		= &rpcb_stats,
 };
-
-/**
- * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister
- *
- */
-void cleanup_rpcb_clnt(void)
-{
-	if (rpcb_local_clnt4)
-		rpc_shutdown_client(rpcb_local_clnt4);
-	if (rpcb_local_clnt)
-		rpc_shutdown_client(rpcb_local_clnt);
-}
diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c
index 9d08091..8ec9778 100644
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -61,8 +61,6 @@ static struct pernet_operations sunrpc_net_ops = {
 
 extern struct cache_detail unix_gid_cache;
 
-extern void cleanup_rpcb_clnt(void);
-
 static int __init
 init_sunrpc(void)
 {
@@ -102,7 +100,6 @@ out:
 static void __exit
 cleanup_sunrpc(void)
 {
-	cleanup_rpcb_clnt();
 	rpcauth_remove_module();
 	cleanup_socket_xprt();
 	svc_cleanup_xprt_sock();

Re: [PATCH 3/5] SUNRPC: make RPC service dependable on rpcbind clients creation

[Stanislav Kinsbursky]

This patch has a flaw: rpcbind clients have to be put in case of error in __svc_create().
So will be the second version.

24.08.2011 22:33, Stanislav Kinsbursky пишет:
> We create or increase users counter of rcbind clients during RPC service
> creation and decrease this counter (and possibly destroy those clients) on RPC
> service destruction.
>
> Signed-off-by: Stanislav Kinsbursky<skinsbursky@parallels.com>
>
> ---
>   include/linux/sunrpc/clnt.h |    2 ++
>   net/sunrpc/rpcb_clnt.c      |    2 +-
>   net/sunrpc/svc.c            |    5 +++++
>   3 files changed, 8 insertions(+), 1 deletions(-)
>
> diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
> index db7bcaf..65a8115 100644
> --- a/include/linux/sunrpc/clnt.h
> +++ b/include/linux/sunrpc/clnt.h
> @@ -135,10 +135,12 @@ void		rpc_shutdown_client(struct rpc_clnt *);
>   void		rpc_release_client(struct rpc_clnt *);
>   void		rpc_task_release_client(struct rpc_task *);
>
> +int		rpcb_create_local(void);
>   int		rpcb_register(u32, u32, int, unsigned short);
>   int		rpcb_v4_register(const u32 program, const u32 version,
>   				 const struct sockaddr *address,
>   				 const char *netid);
> +void		rpcb_put_local(void);
>   void		rpcb_getport_async(struct rpc_task *);
>
>   void		rpc_call_start(struct rpc_task *);
> diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
> index b4cc0f1..437ec60 100644
> --- a/net/sunrpc/rpcb_clnt.c
> +++ b/net/sunrpc/rpcb_clnt.c
> @@ -318,7 +318,7 @@ out:
>    * Returns zero on success, otherwise a negative errno value
>    * is returned.
>    */
> -static int rpcb_create_local(void)
> +int rpcb_create_local(void)
>   {
>   	static DEFINE_MUTEX(rpcb_create_local_mutex);
>   	int result = 0;
> diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
> index 6a69a11..0df8532 100644
> --- a/net/sunrpc/svc.c
> +++ b/net/sunrpc/svc.c
> @@ -367,6 +367,9 @@ __svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
>   	unsigned int xdrsize;
>   	unsigned int i;
>
> +	if (rpcb_create_local()<  0)
> +		return NULL;
> +
>   	if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL)))
>   		return NULL;
>   	serv->sv_name      = prog->pg_name;
> @@ -491,6 +494,8 @@ svc_destroy(struct svc_serv *serv)
>   	svc_unregister(serv);
>   	kfree(serv->sv_pools);
>   	kfree(serv);
> +
> +	rpcb_put_local();
>   }
>   EXPORT_SYMBOL_GPL(svc_destroy);
>
>
> --
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-- 
Best regards,
Stanislav Kinsbursky