[PATCH v2 2/6] NFS: make NFS client allocated per network namespace context

[Stanislav Kinsbursky <skinsbursky@parallels.com>]

This patch adds new net variable to nfs_client structure. This variable is set
on NFS client creation and cheched during matching NFS client search.
Initially current->nsproxy->net_ns is used as network namespace owner for new
NFS client to create. This network namespace pointer is set during mount
options parsing and thus can be passed from user-spave utils in future if will
be necessary.

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

---
 fs/nfs/client.c           |   16 +++++++++++++---
 fs/nfs/internal.h         |    1 +
 fs/nfs/super.c            |    3 +++
 include/linux/nfs_fs_sb.h |    1 +
 4 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 873bf00..4fb5cae 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -135,6 +135,7 @@ struct nfs_client_initdata {
 	const struct nfs_rpc_ops *rpc_ops;
 	int proto;
 	u32 minorversion;
+	struct net *net;
 };
 
 /*
@@ -189,6 +190,7 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
 	if (!IS_ERR(cred))
 		clp->cl_machine_cred = cred;
 	nfs_fscache_get_client_cookie(clp);
+	clp->net = cl_init->net;
 
 	return clp;
 
@@ -476,6 +478,9 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat
 		/* Match the full socket address */
 		if (!nfs_sockaddr_cmp(sap, clap))
 			continue;
+		/* Match network namespace */
+		if (clp->net != data->net)
+			continue;
 
 		atomic_inc(&clp->cl_count);
 		return clp;
@@ -826,6 +831,7 @@ static int nfs_init_server(struct nfs_server *server,
 		.addrlen = data->nfs_server.addrlen,
 		.rpc_ops = &nfs_v2_clientops,
 		.proto = data->nfs_server.protocol,
+		.net = data->net,
 	};
 	struct rpc_timeout timeparms;
 	struct nfs_client *clp;
@@ -1387,7 +1393,7 @@ static int nfs4_set_client(struct nfs_server *server,
 		const char *ip_addr,
 		rpc_authflavor_t authflavour,
 		int proto, const struct rpc_timeout *timeparms,
-		u32 minorversion)
+		u32 minorversion, struct net *net)
 {
 	struct nfs_client_initdata cl_init = {
 		.hostname = hostname,
@@ -1396,6 +1402,7 @@ static int nfs4_set_client(struct nfs_server *server,
 		.rpc_ops = &nfs_v4_clientops,
 		.proto = proto,
 		.minorversion = minorversion,
+		.net = net,
 	};
 	struct nfs_client *clp;
 	int error;
@@ -1447,6 +1454,7 @@ struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
 		.rpc_ops = &nfs_v4_clientops,
 		.proto = ds_proto,
 		.minorversion = mds_clp->cl_minorversion,
+		.net = mds_clp->net,
 	};
 	struct rpc_timeout ds_timeout = {
 		.to_initval = 15 * HZ,
@@ -1573,7 +1581,8 @@ static int nfs4_init_server(struct nfs_server *server,
 			data->auth_flavors[0],
 			data->nfs_server.protocol,
 			&timeparms,
-			data->minorversion);
+			data->minorversion,
+			data->net);
 	if (error < 0)
 		goto error;
 
@@ -1670,7 +1679,8 @@ struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
 				data->authflavor,
 				parent_server->client->cl_xprt->prot,
 				parent_server->client->cl_timeout,
-				parent_client->cl_mvops->minor_version);
+				parent_client->cl_mvops->minor_version,
+				parent_client->net);
 	if (error < 0)
 		goto error;
 
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 3f4d957..c60fa0b 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -123,6 +123,7 @@ struct nfs_parsed_mount_data {
 	} nfs_server;
 
 	struct security_mnt_opts lsm_opts;
+	struct net		*net;
 };
 
 /* mount_clnt.c */
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index b31bdf4..7495039 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -53,6 +53,7 @@
 #include <linux/nfs_xdr.h>
 #include <linux/magic.h>
 #include <linux/parser.h>
+#include <linux/nsproxy.h>
 
 #include <asm/system.h>
 #include <asm/uaccess.h>
@@ -1094,6 +1095,8 @@ static int nfs_parse_mount_options(char *raw,
 
 	free_secdata(secdata);
 
+	mnt->net = current->nsproxy->net_ns;
+
 	while ((p = strsep(&raw, ",")) != NULL) {
 		substring_t args[MAX_OPT_ARGS];
 		unsigned long option;
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index b5479df..71fd605 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -85,6 +85,7 @@ struct nfs_client {
 #endif
 
 	struct server_scope	*server_scope;	/* from exchange_id */
+	struct net		*net;
 };
 
 /*