[PATCH v2 00/12] NFS: callback threads containerization

[PATCH v2 00/12] NFS: callback threads containerization

[Stanislav Kinsbursky]

v2: Rebased on Bruce's tree, "for-3.5" branch

This patch set depeneds on "SUNRPC: separate per-net data creation from service
creation" patch set sent earlier.

The following series implements...

---

Stanislav Kinsbursky (11):
      NFS: pass net to nfs_callback_down()
      NFS: callback service creation function introduced
      NFS: move per-net callback thread initialization to nfs_callback_up_net()
      NFS: callback up - transport backchannel cleanup
      NFS: callback service start function introduced
      NFS: callback up - users counting cleanup
      NFS: make nfs_callback_tcpport per network context
      NFS: make nfs_callback_tcpport6 per network context
      NFS; callback per-net usage counting introduced
      NFS: add debug messages to callback down function
      NFS: get module in idmap PipeFS notifier callback

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


 fs/nfs/callback.c  |  288 ++++++++++++++++++++++++++++++++++------------------
 fs/nfs/callback.h  |    4 -
 fs/nfs/client.c    |    6 +
 fs/nfs/idmap.c     |    9 +-
 fs/nfs/netns.h     |    3 +
 fs/nfs/nfs4state.c |    7 +
 6 files changed, 212 insertions(+), 105 deletions(-)

[PATCH v2 01/12] NFS: pass net to nfs_callback_down()

[Stanislav Kinsbursky]

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c |    4 ++--
 fs/nfs/callback.h |    2 +-
 fs/nfs/client.c   |    2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 970659d..f3d7ee2 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -322,7 +322,7 @@ out_err:
 /*
  * Kill the callback thread if it's no longer being used.
  */
-void nfs_callback_down(int minorversion)
+void nfs_callback_down(int minorversion, struct net *net)
 {
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
 
@@ -330,7 +330,7 @@ void nfs_callback_down(int minorversion)
 	cb_info->users--;
 	if (cb_info->users == 0 && cb_info->task != NULL) {
 		kthread_stop(cb_info->task);
-		svc_shutdown_net(cb_info->serv, current->nsproxy->net_ns);
+		svc_shutdown_net(cb_info->serv, net);
 		svc_exit_thread(cb_info->rqst);
 		cb_info->serv = NULL;
 		cb_info->rqst = NULL;
diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index a5527c9..6d900cf 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -194,7 +194,7 @@ extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
 				   struct cb_process_state *cps);
 #ifdef CONFIG_NFS_V4
 extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);
-extern void nfs_callback_down(int minorversion);
+extern void nfs_callback_down(int minorversion, struct net *net);
 extern int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation,
 					    const nfs4_stateid *stateid);
 extern int nfs4_set_callback_sessionid(struct nfs_client *clp);
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index da7b5e4..44cd70f 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -222,7 +222,7 @@ static void nfs4_shutdown_session(struct nfs_client *clp)
 static void nfs4_destroy_callback(struct nfs_client *clp)
 {
 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
-		nfs_callback_down(clp->cl_mvops->minor_version);
+		nfs_callback_down(clp->cl_mvops->minor_version, clp->net);
 }
 
 static void nfs4_shutdown_client(struct nfs_client *clp)

Re: [PATCH v2 01/12] NFS: pass net to nfs_callback_down()

[J. Bruce Fields]

I can see that you're passing net to nfs_callback_down().  Could you
please remind me why?  What problem does this solve?

--b.

On Tue, May 22, 2012 at 11:35:55AM +0400, Stanislav Kinsbursky wrote:
> Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
> ---
>  fs/nfs/callback.c |    4 ++--
>  fs/nfs/callback.h |    2 +-
>  fs/nfs/client.c   |    2 +-
>  3 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
> index 970659d..f3d7ee2 100644
> --- a/fs/nfs/callback.c
> +++ b/fs/nfs/callback.c
> @@ -322,7 +322,7 @@ out_err:
>  /*
>   * Kill the callback thread if it's no longer being used.
>   */
> -void nfs_callback_down(int minorversion)
> +void nfs_callback_down(int minorversion, struct net *net)
>  {
>  	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
>  
> @@ -330,7 +330,7 @@ void nfs_callback_down(int minorversion)
>  	cb_info->users--;
>  	if (cb_info->users == 0 && cb_info->task != NULL) {
>  		kthread_stop(cb_info->task);
> -		svc_shutdown_net(cb_info->serv, current->nsproxy->net_ns);
> +		svc_shutdown_net(cb_info->serv, net);
>  		svc_exit_thread(cb_info->rqst);
>  		cb_info->serv = NULL;
>  		cb_info->rqst = NULL;
> diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
> index a5527c9..6d900cf 100644
> --- a/fs/nfs/callback.h
> +++ b/fs/nfs/callback.h
> @@ -194,7 +194,7 @@ extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
>  				   struct cb_process_state *cps);
>  #ifdef CONFIG_NFS_V4
>  extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);
> -extern void nfs_callback_down(int minorversion);
> +extern void nfs_callback_down(int minorversion, struct net *net);
>  extern int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation,
>  					    const nfs4_stateid *stateid);
>  extern int nfs4_set_callback_sessionid(struct nfs_client *clp);
> diff --git a/fs/nfs/client.c b/fs/nfs/client.c
> index da7b5e4..44cd70f 100644
> --- a/fs/nfs/client.c
> +++ b/fs/nfs/client.c
> @@ -222,7 +222,7 @@ static void nfs4_shutdown_session(struct nfs_client *clp)
>  static void nfs4_destroy_callback(struct nfs_client *clp)
>  {
>  	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
> -		nfs_callback_down(clp->cl_mvops->minor_version);
> +		nfs_callback_down(clp->cl_mvops->minor_version, clp->net);
>  }
>  
>  static void nfs4_shutdown_client(struct nfs_client *clp)
> 

Re: [PATCH v2 01/12] NFS: pass net to nfs_callback_down()

[Stanislav Kinsbursky]

24.05.2012 20:09, J. Bruce Fields написал:
> I can see that you're passing net to nfs_callback_down().  Could you
> please remind me why?  What problem does this solve?

Callback in a kernel thread and this thread is one for all NFSv4.{0,1} 
clients.
Thus, is have to be cantainerized as Lockd kthread.
This patch set does containerization in the same way as Lockd done.
I forgot about it when I was working on NFS client containerization. So, 
it really hope, that this patch set will be a part of 3.5 kernel.

> --b.
>
> On Tue, May 22, 2012 at 11:35:55AM +0400, Stanislav Kinsbursky wrote:
>> Signed-off-by: Stanislav Kinsbursky<skinsbursky@parallels.com>
>> ---
>>   fs/nfs/callback.c |    4 ++--
>>   fs/nfs/callback.h |    2 +-
>>   fs/nfs/client.c   |    2 +-
>>   3 files changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
>> index 970659d..f3d7ee2 100644
>> --- a/fs/nfs/callback.c
>> +++ b/fs/nfs/callback.c
>> @@ -322,7 +322,7 @@ out_err:
>>   /*
>>    * Kill the callback thread if it's no longer being used.
>>    */
>> -void nfs_callback_down(int minorversion)
>> +void nfs_callback_down(int minorversion, struct net *net)
>>   {
>>   	struct nfs_callback_data *cb_info =&nfs_callback_info[minorversion];
>>
>> @@ -330,7 +330,7 @@ void nfs_callback_down(int minorversion)
>>   	cb_info->users--;
>>   	if (cb_info->users == 0&&  cb_info->task != NULL) {
>>   		kthread_stop(cb_info->task);
>> -		svc_shutdown_net(cb_info->serv, current->nsproxy->net_ns);
>> +		svc_shutdown_net(cb_info->serv, net);
>>   		svc_exit_thread(cb_info->rqst);
>>   		cb_info->serv = NULL;
>>   		cb_info->rqst = NULL;
>> diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
>> index a5527c9..6d900cf 100644
>> --- a/fs/nfs/callback.h
>> +++ b/fs/nfs/callback.h
>> @@ -194,7 +194,7 @@ extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
>>   				   struct cb_process_state *cps);
>>   #ifdef CONFIG_NFS_V4
>>   extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);
>> -extern void nfs_callback_down(int minorversion);
>> +extern void nfs_callback_down(int minorversion, struct net *net);
>>   extern int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation,
>>   					    const nfs4_stateid *stateid);
>>   extern int nfs4_set_callback_sessionid(struct nfs_client *clp);
>> diff --git a/fs/nfs/client.c b/fs/nfs/client.c
>> index da7b5e4..44cd70f 100644
>> --- a/fs/nfs/client.c
>> +++ b/fs/nfs/client.c
>> @@ -222,7 +222,7 @@ static void nfs4_shutdown_session(struct nfs_client *clp)
>>   static void nfs4_destroy_callback(struct nfs_client *clp)
>>   {
>>   	if (__test_and_clear_bit(NFS_CS_CALLBACK,&clp->cl_res_state))
>> -		nfs_callback_down(clp->cl_mvops->minor_version);
>> +		nfs_callback_down(clp->cl_mvops->minor_version, clp->net);
>>   }
>>
>>   static void nfs4_shutdown_client(struct nfs_client *clp)
>>

[PATCH v2 02/12] NFS: callback service creation function introduced

[Stanislav Kinsbursky]

This function creates service if it's not exist, or increase usage counter of
the existent, and returns pointer to it.
Usage counter will be droppepd by svc_destroy() later in nfs_callback_up().

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c |   55 +++++++++++++++++++++++++++++++++++++++++++----------
 1 files changed, 45 insertions(+), 10 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index f3d7ee2..b34ccc6 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -242,12 +242,46 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 }
 #endif /* CONFIG_NFS_V4_1 */
 
+static struct svc_serv *nfs_callback_create_svc(int minorversion)
+{
+	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
+	struct svc_serv *serv;
+
+	/*
+	 * Check whether we're already up and running.
+	 */
+	if (cb_info->task) {
+		/*
+		 * Note: increase service usage, because later in case of error
+		 * svc_destroy() will be called.
+		 */
+		svc_get(cb_info->serv);
+		return cb_info->serv;
+	}
+
+	/*
+	 * Sanity check: if there's no task,
+	 * we should be the first user ...
+	 */
+	if (cb_info->users)
+		printk(KERN_WARNING "nfs_callback_up: no kthread, %d users??\n",
+			cb_info->users);
+
+	serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
+	if (!serv) {
+		printk(KERN_ERR "lockd_up: create service failed\n");
+		return ERR_PTR(-ENOMEM);
+	}
+	dprintk("nfs_callback_up: service created\n");
+	return serv;
+}
+
 /*
  * Bring up the callback thread if it is not already up.
  */
 int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 {
-	struct svc_serv *serv = NULL;
+	struct svc_serv *serv;
 	struct svc_rqst *rqstp;
 	int (*callback_svc)(void *vrqstp);
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
@@ -257,15 +291,17 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 	struct net *net = current->nsproxy->net_ns;
 
 	mutex_lock(&nfs_callback_mutex);
+
+	serv = nfs_callback_create_svc(minorversion);
+	if (IS_ERR(serv)) {
+		ret = PTR_ERR(serv);
+		goto err_create;
+	}
+
 	if (cb_info->users++ || cb_info->task != NULL) {
 		nfs_callback_bc_serv(minorversion, xprt, cb_info);
 		goto out;
 	}
-	serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
-	if (!serv) {
-		ret = -ENOMEM;
-		goto out_err;
-	}
 
 	ret = svc_bind(serv, net);
 	if (ret < 0) {
@@ -306,16 +342,15 @@ out:
 	 * on both success and failure so that the refcount is 1 when the
 	 * thread exits.
 	 */
-	if (serv)
-		svc_destroy(serv);
+	svc_destroy(serv);
+err_create:
 	mutex_unlock(&nfs_callback_mutex);
 	return ret;
 out_err:
 	dprintk("NFS: Couldn't create callback socket or server thread; "
 		"err = %d\n", ret);
 	cb_info->users--;
-	if (serv)
-		svc_shutdown_net(serv, net);
+	svc_shutdown_net(serv, net);
 	goto out;
 }
 

[PATCH v2 03/12] NFS: move per-net callback thread initialization to nfs_callback_up_net()

[Stanislav Kinsbursky]

This new function in now called before nfs_minorversion_callback_svc_setup()).

Also few small changes:
1) current network namespace in nfs_callback_up() was replaced by transport net.
2) svc_shutdown_net() was moved prior to callback usage counter decrement
(because in case of per-net data allocation faulure svc_shutdown_net() have to
be skipped).

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c |  125 +++++++++++++++++++++++++++++++++--------------------
 1 files changed, 78 insertions(+), 47 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index b34ccc6..2ecea36 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -64,6 +64,32 @@ static struct kernel_param_ops param_ops_portnr = {
 
 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
 
+static int nfs4_callback_up_net(struct svc_serv *serv, struct net *net)
+{
+	int ret;
+
+	ret = svc_create_xprt(serv, "tcp", net, PF_INET,
+				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
+	if (ret <= 0)
+		goto out_err;
+	nfs_callback_tcpport = ret;
+	dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
+			nfs_callback_tcpport, PF_INET, net);
+
+	ret = svc_create_xprt(serv, "tcp", net, PF_INET6,
+				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
+	if (ret > 0) {
+		nfs_callback_tcpport6 = ret;
+		dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
+				nfs_callback_tcpport6, PF_INET6, net);
+	} else if (ret != -EAFNOSUPPORT)
+		goto out_err;
+	return 0;
+
+out_err:
+	return (ret) ? ret : -ENOMEM;
+}
+
 /*
  * This is the NFSv4 callback kernel thread.
  */
@@ -105,36 +131,21 @@ nfs4_callback_svc(void *vrqstp)
 static struct svc_rqst *
 nfs4_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
 {
-	int ret;
-
-	ret = svc_create_xprt(serv, "tcp", xprt->xprt_net, PF_INET,
-				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
-	if (ret <= 0)
-		goto out_err;
-	nfs_callback_tcpport = ret;
-	dprintk("NFS: Callback listener port = %u (af %u)\n",
-			nfs_callback_tcpport, PF_INET);
-
-	ret = svc_create_xprt(serv, "tcp", xprt->xprt_net, PF_INET6,
-				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
-	if (ret > 0) {
-		nfs_callback_tcpport6 = ret;
-		dprintk("NFS: Callback listener port = %u (af %u)\n",
-				nfs_callback_tcpport6, PF_INET6);
-	} else if (ret == -EAFNOSUPPORT)
-		ret = 0;
-	else
-		goto out_err;
-
 	return svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
-
-out_err:
-	if (ret == 0)
-		ret = -ENOMEM;
-	return ERR_PTR(ret);
 }
 
 #if defined(CONFIG_NFS_V4_1)
+static int nfs41_callback_up_net(struct svc_serv *serv, struct net *net)
+{
+	/*
+	 * Create an svc_sock for the back channel service that shares the
+	 * fore channel connection.
+	 * Returns the input port (0) and sets the svc_serv bc_xprt on success
+	 */
+	return svc_create_xprt(serv, "tcp-bc", net, PF_INET, 0,
+			      SVC_SOCK_ANONYMOUS);
+}
+
 /*
  * The callback service for NFSv4.1 callbacks
  */
@@ -177,19 +188,6 @@ static struct svc_rqst *
 nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
 {
 	struct svc_rqst *rqstp;
-	int ret;
-
-	/*
-	 * Create an svc_sock for the back channel service that shares the
-	 * fore channel connection.
-	 * Returns the input port (0) and sets the svc_serv bc_xprt on success
-	 */
-	ret = svc_create_xprt(serv, "tcp-bc", xprt->xprt_net, PF_INET, 0,
-			      SVC_SOCK_ANONYMOUS);
-	if (ret < 0) {
-		rqstp = ERR_PTR(ret);
-		goto out;
-	}
 
 	/*
 	 * Save the svc_serv in the transport so that it can
@@ -205,7 +203,6 @@ nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
 		svc_xprt_put(serv->sv_bc_xprt);
 		serv->sv_bc_xprt = NULL;
 	}
-out:
 	dprintk("--> %s return %ld\n", __func__,
 		IS_ERR(rqstp) ? PTR_ERR(rqstp) : 0);
 	return rqstp;
@@ -229,6 +226,11 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 		xprt->bc_serv = cb_info->serv;
 }
 #else
+static int nfs41_callback_up_net(struct svc_serv *serv, struct net *net)
+{
+	return 0;
+}
+
 static inline int nfs_minorversion_callback_svc_setup(u32 minorversion,
 		struct svc_serv *serv, struct rpc_xprt *xprt,
 		struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
@@ -242,6 +244,36 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 }
 #endif /* CONFIG_NFS_V4_1 */
 
+static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct net *net)
+{
+	int ret;
+
+	dprintk("NFS: create per-net callback data; net=%p\n", net);
+
+	ret = svc_bind(serv, net);
+	if (ret < 0) {
+		printk(KERN_WARNING "NFS: bind callback service failed\n");
+		goto err_bind;
+	}
+
+	if (minorversion) {
+		ret = nfs41_callback_up_net(serv, net);
+		if (ret < 0)
+			goto err_socks;
+	}
+
+	if (ret == 0)
+		ret = nfs4_callback_up_net(serv, net);
+	if (ret < 0)
+		goto err_socks;
+	return 0;
+
+err_socks:
+	svc_rpcb_cleanup(serv, net);
+err_bind:
+	return ret;
+}
+
 static struct svc_serv *nfs_callback_create_svc(int minorversion)
 {
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
@@ -288,7 +320,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 	char svc_name[12];
 	int ret = 0;
 	int minorversion_setup;
-	struct net *net = current->nsproxy->net_ns;
+	struct net *net = xprt->xprt_net;
 
 	mutex_lock(&nfs_callback_mutex);
 
@@ -303,11 +335,9 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 		goto out;
 	}
 
-	ret = svc_bind(serv, net);
-	if (ret < 0) {
-		printk(KERN_WARNING "NFS: bind callback service failed\n");
-		goto out_err;
-	}
+	ret = nfs_callback_up_net(minorversion, serv, net);
+	if (ret < 0)
+		goto err_net;
 
 	minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
 					serv, xprt, &rqstp, &callback_svc);
@@ -347,10 +377,11 @@ err_create:
 	mutex_unlock(&nfs_callback_mutex);
 	return ret;
 out_err:
+	svc_shutdown_net(serv, net);
+err_net:
 	dprintk("NFS: Couldn't create callback socket or server thread; "
 		"err = %d\n", ret);
 	cb_info->users--;
-	svc_shutdown_net(serv, net);
 	goto out;
 }
 

[PATCH v2 04/12] NFS: callback up - transport backchannel cleanup

[Stanislav Kinsbursky]

No need to assign transports backchannel server explicitly in
nfs41_callback_up() -  there is nfs_callback_bc_serv() function for this.
By using it, nfs4_callback_up() and nfs41_callback_up() can be called without
transport argument.

Note: service have to be passed to nfs_callback_bc_serv() instead of callback,
since callback link can be uninitialized.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c |   34 +++++++++++++++++-----------------
 1 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 2ecea36..3e6aead 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -129,7 +129,7 @@ nfs4_callback_svc(void *vrqstp)
  * Prepare to bring up the NFSv4 callback service
  */
 static struct svc_rqst *
-nfs4_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
+nfs4_callback_up(struct svc_serv *serv)
 {
 	return svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
 }
@@ -185,16 +185,10 @@ nfs41_callback_svc(void *vrqstp)
  * Bring up the NFSv4.1 callback service
  */
 static struct svc_rqst *
-nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
+nfs41_callback_up(struct svc_serv *serv)
 {
 	struct svc_rqst *rqstp;
 
-	/*
-	 * Save the svc_serv in the transport so that it can
-	 * be referenced when the session backchannel is initialized
-	 */
-	xprt->bc_serv = serv;
-
 	INIT_LIST_HEAD(&serv->sv_cb_list);
 	spin_lock_init(&serv->sv_cb_lock);
 	init_waitqueue_head(&serv->sv_cb_waitq);
@@ -209,21 +203,25 @@ nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
 }
 
 static inline int nfs_minorversion_callback_svc_setup(u32 minorversion,
-		struct svc_serv *serv, struct rpc_xprt *xprt,
+		struct svc_serv *serv,
 		struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
 {
 	if (minorversion) {
-		*rqstpp = nfs41_callback_up(serv, xprt);
+		*rqstpp = nfs41_callback_up(serv);
 		*callback_svc = nfs41_callback_svc;
 	}
 	return minorversion;
 }
 
 static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
-		struct nfs_callback_data *cb_info)
+		struct svc_serv *serv)
 {
 	if (minorversion)
-		xprt->bc_serv = cb_info->serv;
+		/*
+		 * Save the svc_serv in the transport so that it can
+		 * be referenced when the session backchannel is initialized
+		 */
+		xprt->bc_serv = serv;
 }
 #else
 static int nfs41_callback_up_net(struct svc_serv *serv, struct net *net)
@@ -232,14 +230,14 @@ static int nfs41_callback_up_net(struct svc_serv *serv, struct net *net)
 }
 
 static inline int nfs_minorversion_callback_svc_setup(u32 minorversion,
-		struct svc_serv *serv, struct rpc_xprt *xprt,
+		struct svc_serv *serv,
 		struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
 {
 	return 0;
 }
 
 static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
-		struct nfs_callback_data *cb_info)
+		struct svc_serv *serv)
 {
 }
 #endif /* CONFIG_NFS_V4_1 */
@@ -331,7 +329,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 	}
 
 	if (cb_info->users++ || cb_info->task != NULL) {
-		nfs_callback_bc_serv(minorversion, xprt, cb_info);
+		nfs_callback_bc_serv(minorversion, xprt, serv);
 		goto out;
 	}
 
@@ -339,11 +337,13 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 	if (ret < 0)
 		goto err_net;
 
+	nfs_callback_bc_serv(minorversion, xprt, serv);
+
 	minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
-					serv, xprt, &rqstp, &callback_svc);
+					serv, &rqstp, &callback_svc);
 	if (!minorversion_setup) {
 		/* v4.0 callback setup */
-		rqstp = nfs4_callback_up(serv, xprt);
+		rqstp = nfs4_callback_up(serv);
 		callback_svc = nfs4_callback_svc;
 	}
 

[PATCH v2 05/12] NFS: callback service start function introduced

[Stanislav Kinsbursky]

This is just a code move, which from my POW makes code looks better.
I.e. now on start we have 3 different stages:
1) Service creation.
2) Service per-net data allocation.
3) Service start.

Patch also renames goto label "out_err:" into "err_start:" to reflect new
changes.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c |   77 +++++++++++++++++++++++++++++++----------------------
 1 files changed, 45 insertions(+), 32 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 3e6aead..8643ff7 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -242,6 +242,46 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 }
 #endif /* CONFIG_NFS_V4_1 */
 
+static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
+				  struct svc_serv *serv)
+{
+	struct svc_rqst *rqstp;
+	int (*callback_svc)(void *vrqstp);
+	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
+	char svc_name[12];
+	int ret;
+	int minorversion_setup;
+
+	nfs_callback_bc_serv(minorversion, xprt, serv);
+
+	minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
+					serv, &rqstp, &callback_svc);
+	if (!minorversion_setup) {
+		/* v4.0 callback setup */
+		rqstp = nfs4_callback_up(serv);
+		callback_svc = nfs4_callback_svc;
+	}
+
+	if (IS_ERR(rqstp))
+		return PTR_ERR(rqstp);
+
+	svc_sock_update_bufs(serv);
+
+	sprintf(svc_name, "nfsv4.%u-svc", minorversion);
+	cb_info->serv = serv;
+	cb_info->rqst = rqstp;
+	cb_info->task = kthread_run(callback_svc, cb_info->rqst, svc_name);
+	if (IS_ERR(cb_info->task)) {
+		ret = PTR_ERR(cb_info->task);
+		svc_exit_thread(cb_info->rqst);
+		cb_info->rqst = NULL;
+		cb_info->task = NULL;
+		return PTR_ERR(cb_info->task);
+	}
+	dprintk("nfs_callback_up: service started\n");
+	return 0;
+}
+
 static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct net *net)
 {
 	int ret;
@@ -312,12 +352,8 @@ static struct svc_serv *nfs_callback_create_svc(int minorversion)
 int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 {
 	struct svc_serv *serv;
-	struct svc_rqst *rqstp;
-	int (*callback_svc)(void *vrqstp);
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
-	char svc_name[12];
 	int ret = 0;
-	int minorversion_setup;
 	struct net *net = xprt->xprt_net;
 
 	mutex_lock(&nfs_callback_mutex);
@@ -337,34 +373,10 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 	if (ret < 0)
 		goto err_net;
 
-	nfs_callback_bc_serv(minorversion, xprt, serv);
-
-	minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
-					serv, &rqstp, &callback_svc);
-	if (!minorversion_setup) {
-		/* v4.0 callback setup */
-		rqstp = nfs4_callback_up(serv);
-		callback_svc = nfs4_callback_svc;
-	}
-
-	if (IS_ERR(rqstp)) {
-		ret = PTR_ERR(rqstp);
-		goto out_err;
-	}
-
-	svc_sock_update_bufs(serv);
+	ret = nfs_callback_start_svc(minorversion, xprt, serv);
+	if (ret < 0)
+		goto err_start;
 
-	sprintf(svc_name, "nfsv4.%u-svc", minorversion);
-	cb_info->serv = serv;
-	cb_info->rqst = rqstp;
-	cb_info->task = kthread_run(callback_svc, cb_info->rqst, svc_name);
-	if (IS_ERR(cb_info->task)) {
-		ret = PTR_ERR(cb_info->task);
-		svc_exit_thread(cb_info->rqst);
-		cb_info->rqst = NULL;
-		cb_info->task = NULL;
-		goto out_err;
-	}
 out:
 	/*
 	 * svc_create creates the svc_serv with sv_nrthreads == 1, and then
@@ -376,7 +388,8 @@ out:
 err_create:
 	mutex_unlock(&nfs_callback_mutex);
 	return ret;
-out_err:
+
+err_start:
 	svc_shutdown_net(serv, net);
 err_net:
 	dprintk("NFS: Couldn't create callback socket or server thread; "

[PATCH v2 06/12] NFS: callback up - users counting cleanup

[Stanislav Kinsbursky]

Usage coutner now increased only is the service was started sccessfully.
Even if service is running already, then goto is not required anymore, because
service creation and start will be skipped.
With this patch code looks clearer.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c |   22 ++++++++++------------
 1 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 8643ff7..11201dd 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -254,6 +254,9 @@ static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
 
 	nfs_callback_bc_serv(minorversion, xprt, serv);
 
+	if (cb_info->task)
+		return 0;
+
 	minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
 					serv, &rqstp, &callback_svc);
 	if (!minorversion_setup) {
@@ -309,6 +312,8 @@ static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct n
 err_socks:
 	svc_rpcb_cleanup(serv, net);
 err_bind:
+	dprintk("NFS: Couldn't create callback socket: err = %d; "
+			"net = %p\n", ret, net);
 	return ret;
 }
 
@@ -353,7 +358,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 {
 	struct svc_serv *serv;
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
-	int ret = 0;
+	int ret;
 	struct net *net = xprt->xprt_net;
 
 	mutex_lock(&nfs_callback_mutex);
@@ -364,11 +369,6 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 		goto err_create;
 	}
 
-	if (cb_info->users++ || cb_info->task != NULL) {
-		nfs_callback_bc_serv(minorversion, xprt, serv);
-		goto out;
-	}
-
 	ret = nfs_callback_up_net(minorversion, serv, net);
 	if (ret < 0)
 		goto err_net;
@@ -377,13 +377,14 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 	if (ret < 0)
 		goto err_start;
 
-out:
+	cb_info->users++;
 	/*
 	 * svc_create creates the svc_serv with sv_nrthreads == 1, and then
 	 * svc_prepare_thread increments that. So we need to call svc_destroy
 	 * on both success and failure so that the refcount is 1 when the
 	 * thread exits.
 	 */
+err_net:
 	svc_destroy(serv);
 err_create:
 	mutex_unlock(&nfs_callback_mutex);
@@ -391,11 +392,8 @@ err_create:
 
 err_start:
 	svc_shutdown_net(serv, net);
-err_net:
-	dprintk("NFS: Couldn't create callback socket or server thread; "
-		"err = %d\n", ret);
-	cb_info->users--;
-	goto out;
+	dprintk("NFS: Couldn't create server thread; err = %d\n", ret);
+	goto err_net;
 }
 
 /*

[PATCH v2 07/12] NFS: make nfs_callback_tcpport per network context

[Stanislav Kinsbursky]

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c  |    7 ++++---
 fs/nfs/callback.h  |    1 -
 fs/nfs/netns.h     |    1 +
 fs/nfs/nfs4state.c |    5 ++++-
 4 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 11201dd..9380184 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -24,6 +24,7 @@
 #include "nfs4_fs.h"
 #include "callback.h"
 #include "internal.h"
+#include "netns.h"
 
 #define NFSDBG_FACILITY NFSDBG_CALLBACK
 
@@ -39,7 +40,6 @@ static DEFINE_MUTEX(nfs_callback_mutex);
 static struct svc_program nfs4_callback_program;
 
 unsigned int nfs_callback_set_tcpport;
-unsigned short nfs_callback_tcpport;
 unsigned short nfs_callback_tcpport6;
 #define NFS_CALLBACK_MAXPORTNR (65535U)
 
@@ -67,14 +67,15 @@ module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
 static int nfs4_callback_up_net(struct svc_serv *serv, struct net *net)
 {
 	int ret;
+	struct nfs_net *nn = net_generic(net, nfs_net_id);
 
 	ret = svc_create_xprt(serv, "tcp", net, PF_INET,
 				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
 	if (ret <= 0)
 		goto out_err;
-	nfs_callback_tcpport = ret;
+	nn->nfs_callback_tcpport = ret;
 	dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
-			nfs_callback_tcpport, PF_INET, net);
+			nn->nfs_callback_tcpport, PF_INET, net);
 
 	ret = svc_create_xprt(serv, "tcp", net, PF_INET6,
 				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index 6d900cf..8006959 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -208,7 +208,6 @@ extern int nfs4_set_callback_sessionid(struct nfs_client *clp);
 #define NFS41_BC_MAX_CALLBACKS 1
 
 extern unsigned int nfs_callback_set_tcpport;
-extern unsigned short nfs_callback_tcpport;
 extern unsigned short nfs_callback_tcpport6;
 
 #endif /* __LINUX_FS_NFS_CALLBACK_H */
diff --git a/fs/nfs/netns.h b/fs/nfs/netns.h
index aa14ec3..8e4e8f8 100644
--- a/fs/nfs/netns.h
+++ b/fs/nfs/netns.h
@@ -18,6 +18,7 @@ struct nfs_net {
 	struct list_head nfs_volume_list;
 #ifdef CONFIG_NFS_V4
 	struct idr cb_ident_idr; /* Protected by nfs_client_lock */
+	unsigned short nfs_callback_tcpport;
 #endif
 	spinlock_t nfs_client_lock;
 };
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 0f43414..5d68b3b 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -57,6 +57,8 @@
 #include "internal.h"
 #include "pnfs.h"
 
+#include "netns.h"
+
 #define OPENOWNER_POOL_SIZE	8
 
 const nfs4_stateid zero_stateid;
@@ -71,10 +73,11 @@ int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 	};
 	unsigned short port;
 	int status;
+	struct nfs_net *nn = net_generic(clp->net, nfs_net_id);
 
 	if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 		goto do_confirm;
-	port = nfs_callback_tcpport;
+	port = nn->nfs_callback_tcpport;
 	if (clp->cl_addr.ss_family == AF_INET6)
 		port = nfs_callback_tcpport6;
 

[PATCH v2 08/12] NFS: make nfs_callback_tcpport6 per network context

[Stanislav Kinsbursky]

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c  |    5 ++---
 fs/nfs/callback.h  |    1 -
 fs/nfs/netns.h     |    1 +
 fs/nfs/nfs4state.c |    2 +-
 4 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 9380184..d25085f 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -40,7 +40,6 @@ static DEFINE_MUTEX(nfs_callback_mutex);
 static struct svc_program nfs4_callback_program;
 
 unsigned int nfs_callback_set_tcpport;
-unsigned short nfs_callback_tcpport6;
 #define NFS_CALLBACK_MAXPORTNR (65535U)
 
 static int param_set_portnr(const char *val, const struct kernel_param *kp)
@@ -80,9 +79,9 @@ static int nfs4_callback_up_net(struct svc_serv *serv, struct net *net)
 	ret = svc_create_xprt(serv, "tcp", net, PF_INET6,
 				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
 	if (ret > 0) {
-		nfs_callback_tcpport6 = ret;
+		nn->nfs_callback_tcpport6 = ret;
 		dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
-				nfs_callback_tcpport6, PF_INET6, net);
+				nn->nfs_callback_tcpport6, PF_INET6, net);
 	} else if (ret != -EAFNOSUPPORT)
 		goto out_err;
 	return 0;
diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index 8006959..86b5671 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -208,6 +208,5 @@ extern int nfs4_set_callback_sessionid(struct nfs_client *clp);
 #define NFS41_BC_MAX_CALLBACKS 1
 
 extern unsigned int nfs_callback_set_tcpport;
-extern unsigned short nfs_callback_tcpport6;
 
 #endif /* __LINUX_FS_NFS_CALLBACK_H */
diff --git a/fs/nfs/netns.h b/fs/nfs/netns.h
index 8e4e8f8..bd72a55 100644
--- a/fs/nfs/netns.h
+++ b/fs/nfs/netns.h
@@ -19,6 +19,7 @@ struct nfs_net {
 #ifdef CONFIG_NFS_V4
 	struct idr cb_ident_idr; /* Protected by nfs_client_lock */
 	unsigned short nfs_callback_tcpport;
+	unsigned short nfs_callback_tcpport6;
 #endif
 	spinlock_t nfs_client_lock;
 };
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 5d68b3b..bee4bc1 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -79,7 +79,7 @@ int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 		goto do_confirm;
 	port = nn->nfs_callback_tcpport;
 	if (clp->cl_addr.ss_family == AF_INET6)
-		port = nfs_callback_tcpport6;
+		port = nn->nfs_callback_tcpport6;
 
 	status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
 	if (status != 0)

[PATCH v2 09/12] NFS; callback per-net usage counting introduced

[Stanislav Kinsbursky]

This patch also introduces refcount-aware nfs_callback_down_net() wrapper for
svc_shutdown_net().

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c |   19 +++++++++++++++++--
 fs/nfs/netns.h    |    1 +
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index d25085f..dbedd7e 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -285,10 +285,25 @@ static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
 	return 0;
 }
 
+static void nfs_callback_down_net(u32 minorversion, struct svc_serv *serv, struct net *net)
+{
+	struct nfs_net *nn = net_generic(net, nfs_net_id);
+
+	if (--nn->cb_users[minorversion])
+		return;
+
+	dprintk("NFS: destroy per-net callback data; net=%p\n", net);
+	svc_shutdown_net(serv, net);
+}
+
 static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct net *net)
 {
+	struct nfs_net *nn = net_generic(net, nfs_net_id);
 	int ret;
 
+	if (nn->cb_users[minorversion]++)
+		return 0;
+
 	dprintk("NFS: create per-net callback data; net=%p\n", net);
 
 	ret = svc_bind(serv, net);
@@ -391,7 +406,7 @@ err_create:
 	return ret;
 
 err_start:
-	svc_shutdown_net(serv, net);
+	nfs_callback_down_net(minorversion, serv, net);
 	dprintk("NFS: Couldn't create server thread; err = %d\n", ret);
 	goto err_net;
 }
@@ -404,10 +419,10 @@ void nfs_callback_down(int minorversion, struct net *net)
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
 
 	mutex_lock(&nfs_callback_mutex);
+	nfs_callback_down_net(minorversion, cb_info->serv, net);
 	cb_info->users--;
 	if (cb_info->users == 0 && cb_info->task != NULL) {
 		kthread_stop(cb_info->task);
-		svc_shutdown_net(cb_info->serv, net);
 		svc_exit_thread(cb_info->rqst);
 		cb_info->serv = NULL;
 		cb_info->rqst = NULL;
diff --git a/fs/nfs/netns.h b/fs/nfs/netns.h
index bd72a55..db3e495 100644
--- a/fs/nfs/netns.h
+++ b/fs/nfs/netns.h
@@ -20,6 +20,7 @@ struct nfs_net {
 	struct idr cb_ident_idr; /* Protected by nfs_client_lock */
 	unsigned short nfs_callback_tcpport;
 	unsigned short nfs_callback_tcpport6;
+	int cb_users[NFS4_MAX_MINOR_VERSION + 1];
 #endif
 	spinlock_t nfs_client_lock;
 };

[PATCH v2 10/12] NFS: add debug messages to callback down function

[Stanislav Kinsbursky]

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/callback.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index dbedd7e..2db796a 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -423,7 +423,9 @@ void nfs_callback_down(int minorversion, struct net *net)
 	cb_info->users--;
 	if (cb_info->users == 0 && cb_info->task != NULL) {
 		kthread_stop(cb_info->task);
+		dprintk("nfs_callback_down: service stopped\n");
 		svc_exit_thread(cb_info->rqst);
+		dprintk("nfs_callback_down: service destroyed\n");
 		cb_info->serv = NULL;
 		cb_info->rqst = NULL;
 		cb_info->task = NULL;

[PATCH v2 11/12] Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

[Stanislav Kinsbursky]

From: root (none) <root@sighted>


---
 fs/nfs/client.c |    4 +++-
 fs/nfs/idmap.c  |    5 ++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 44cd70f..ae29d4f 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -176,8 +176,10 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
 
 #ifdef CONFIG_NFS_V4
 	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
-	if (err)
+	if (err) {
+		put_net(clp->net);
 		goto error_cleanup;
+	}
 
 	spin_lock_init(&clp->cl_lock);
 	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index b7f348b..c9c3e1b 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -487,7 +487,7 @@ nfs_idmap_delete(struct nfs_client *clp)
 	kfree(idmap);
 }
 
-static int __rpc_pipefs_event(struct nfs_client *clp, unsigned long event,
+static noinline int __rpc_pipefs_event(struct nfs_client *clp, unsigned long event,
 			      struct super_block *sb)
 {
 	int err = 0;
@@ -533,8 +533,11 @@ static struct nfs_client *nfs_get_client_for_event(struct net *net, int event)
 
 	spin_lock(&nn->nfs_client_lock);
 	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
+		BUG_ON(atomic_read(&clp->cl_count) == 0);
 		if (clp->rpc_ops != &nfs_v4_clientops)
 			continue;
+		BUG_ON(clp->cl_idmap == NULL);
+		BUG_ON(clp->cl_idmap->idmap_pipe == NULL);
 		cl_dentry = clp->cl_idmap->idmap_pipe->dentry;
 		if (((event == RPC_PIPEFS_MOUNT) && cl_dentry) ||
 		    ((event == RPC_PIPEFS_UMOUNT) && !cl_dentry))

[PATCH v3] NFS: put net on idr allocation failure

[Stanislav Kinsbursky]

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/client.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 44cd70f..ae29d4f 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -176,8 +176,10 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
 
 #ifdef CONFIG_NFS_V4
 	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
-	if (err)
+	if (err) {
+		put_net(clp->net);
 		goto error_cleanup;
+	}
 
 	spin_lock_init(&clp->cl_lock);
 	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);

Re: [PATCH v3] NFS: put net on idr allocation failure

[Myklebust, Trond]
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Re: [PATCH v3] NFS: put net on idr allocation failure

[Stanislav Kinsbursky]

On 22.05.2012 18:37, Myklebust, Trond wrote:
> On Tue, 2012-05-22 at 12:03 +0400, Stanislav Kinsbursky wrote:
>> Signed-off-by: Stanislav Kinsbursky<skinsbursky@parallels.com>
>> ---
>>   fs/nfs/client.c |    4 +++-
>>   1 files changed, 3 insertions(+), 1 deletions(-)
>>
>> diff --git a/fs/nfs/client.c b/fs/nfs/client.c
>> index 44cd70f..ae29d4f 100644
>> --- a/fs/nfs/client.c
>> +++ b/fs/nfs/client.c
>> @@ -176,8 +176,10 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
>>
>>   #ifdef CONFIG_NFS_V4
>>   	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
>> -	if (err)
>> +	if (err) {
>> +		put_net(clp->net);
>>   		goto error_cleanup;
>> +	}
>>
>>   	spin_lock_init(&clp->cl_lock);
>>   	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
>>
>
> Let's just move the actual get_net() call to the end of the function.
>

Ok. But it will look a bit strange, like this:

clp->net = net;
...
nfs_get_cb_ident_idr
...
get_net(clp->net)

Or I can pass net to nfs_get_cb_ident_idr() as a parameter.
Which solution is more preferable&?

-- 
Best regards,
Stanislav Kinsbursky

Re: [PATCH v3] NFS: put net on idr allocation failure

[Myklebust, Trond]
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=

Re: [PATCH v3] NFS: put net on idr allocation failure

[Stanislav Kinsbursky]

On 22.05.2012 18:45, Myklebust, Trond wrote:
> On Tue, 2012-05-22 at 18:41 +0400, Stanislav Kinsbursky wrote:
>> On 22.05.2012 18:37, Myklebust, Trond wrote:
>>> On Tue, 2012-05-22 at 12:03 +0400, Stanislav Kinsbursky wrote:
>>>> Signed-off-by: Stanislav Kinsbursky<skinsbursky@parallels.com>
>>>> ---
>>>>    fs/nfs/client.c |    4 +++-
>>>>    1 files changed, 3 insertions(+), 1 deletions(-)
>>>>
>>>> diff --git a/fs/nfs/client.c b/fs/nfs/client.c
>>>> index 44cd70f..ae29d4f 100644
>>>> --- a/fs/nfs/client.c
>>>> +++ b/fs/nfs/client.c
>>>> @@ -176,8 +176,10 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
>>>>
>>>>    #ifdef CONFIG_NFS_V4
>>>>    	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
>>>> -	if (err)
>>>> +	if (err) {
>>>> +		put_net(clp->net);
>>>>    		goto error_cleanup;
>>>> +	}
>>>>
>>>>    	spin_lock_init(&clp->cl_lock);
>>>>    	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
>>>>
>>>
>>> Let's just move the actual get_net() call to the end of the function.
>>>
>>
>> Ok. But it will look a bit strange, like this:
>>
>> clp->net = net;
>> ...
>> nfs_get_cb_ident_idr
>> ...
>> get_net(clp->net)
>>
>> Or I can pass net to nfs_get_cb_ident_idr() as a parameter.
>> Which solution is more preferable&?
>
> Just put the get_net() at the end. It doesn't matter if it looks a bit
> odd: the intent is still obvious.
>

Sure.

-- 
Best regards,
Stanislav Kinsbursky

[PATCH v4] NFS: get client net after idr allocation

[Stanislav Kinsbursky]

Allocation can fail. So instead of put net in case of failure, get net after
allocation.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/client.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index b59419a..b694971 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -172,7 +172,7 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
 	clp->cl_rpcclient = ERR_PTR(-EINVAL);
 
 	clp->cl_proto = cl_init->proto;
-	clp->net = get_net(cl_init->net);
+	clp->net = cl_init->net;
 
 #ifdef CONFIG_NFS_V4
 	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
@@ -187,6 +187,7 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
 	clp->cl_minorversion = cl_init->minorversion;
 	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 #endif
+	get_net(clp->net);
 	cred = rpc_lookup_machine_cred("*");
 	if (!IS_ERR(cred))
 		clp->cl_machine_cred = cred;

Re: [PATCH v2 11/12] Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

[Myklebust, Trond]

T24gVHVlLCAyMDEyLTA1LTIyIGF0IDExOjM3ICswNDAwLCBTdGFuaXNsYXYgS2luc2J1cnNreSB3
cm90ZToNCj4gRnJvbTogcm9vdCAobm9uZSkgPHJvb3RAc2lnaHRlZD4NCj4gDQoNCldoYXQgaGFw
cGVuZWQgdG8gdGhlIFN1YmplY3Q6IGFuZCBjaGFuZ2Vsb2c/DQoNCi0tIA0KVHJvbmQgTXlrbGVi
dXN0DQpMaW51eCBORlMgY2xpZW50IG1haW50YWluZXINCg0KTmV0QXBwDQpUcm9uZC5NeWtsZWJ1
c3RAbmV0YXBwLmNvbQ0Kd3d3Lm5ldGFwcC5jb20NCg0K

Re: [PATCH v2 11/12] Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

[Stanislav Kinsbursky]

On 22.05.2012 18:38, Myklebust, Trond wrote:
> On Tue, 2012-05-22 at 11:37 +0400, Stanislav Kinsbursky wrote:
>> From: root (none)<root@sighted>
>>
>
> What happened to the Subject: and changelog?
>

Sorry for this.
That's why I've sent "v3" - added subject and changelog.

-- 
Best regards,
Stanislav Kinsbursky

[PATCH v2 12/12] NFS: get module in idmap PipeFS notifier callback

[Stanislav Kinsbursky]

This is bug fix.
Notifier callback is called from SUNRPC module. So before dereferencing NFS
module we have to make sure, that it's alive.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
 fs/nfs/idmap.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index c9c3e1b..f55b80a 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -557,12 +557,16 @@ static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
 	struct nfs_client *clp;
 	int error = 0;
 
+	if (!try_module_get(THIS_MODULE))
+		return 0;
+
 	while ((clp = nfs_get_client_for_event(sb->s_fs_info, event))) {
 		error = __rpc_pipefs_event(clp, event, sb);
 		nfs_put_client(clp);
 		if (error)
 			break;
 	}
+	module_put(THIS_MODULE);
 	return error;
 }