NFS: make cb_ident_idr per net ns

This patch makes ID's infrastructure network namespace aware. This was done
mainly because of nfs_client_lock, which is desired to be per network
namespace, but protects NFS clients ID's.

NOTE: NFS client's net pointer have to be set prior to ID initialization,
proper assignment was moved.

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

fs/nfs/callback_xdr.c

@@ -876,7 +876,7 @@ static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *r
 		return rpc_garbage_args;
 
 	if (hdr_arg.minorversion == 0) {
-		cps.clp = nfs4_find_client_ident(hdr_arg.cb_ident);
+		cps.clp = nfs4_find_client_ident(rqstp->rq_xprt->xpt_net, hdr_arg.cb_ident);
 		if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 			return rpc_drop_reply;
 	}

fs/nfs/client.c

@@ -58,7 +58,6 @@
 DEFINE_SPINLOCK(nfs_client_lock);
 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
 #ifdef CONFIG_NFS_V4
-static DEFINE_IDR(cb_ident_idr); /* Protected by nfs_client_lock */
 
 /*
  * Get a unique NFSv4.0 callback identifier which will be used
@@ -67,14 +66,15 @@ static DEFINE_IDR(cb_ident_idr); /* Protected by nfs_client_lock */
 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
 {
 	int ret = 0;
+	struct nfs_net *nn = net_generic(clp->net, nfs_net_id);
 
 	if (clp->rpc_ops->version != 4 || minorversion != 0)
 		return ret;
 retry:
-	if (!idr_pre_get(&cb_ident_idr, GFP_KERNEL))
+	if (!idr_pre_get(&nn->cb_ident_idr, GFP_KERNEL))
 		return -ENOMEM;
 	spin_lock(&nfs_client_lock);
-	ret = idr_get_new(&cb_ident_idr, clp, &clp->cl_cb_ident);
+	ret = idr_get_new(&nn->cb_ident_idr, clp, &clp->cl_cb_ident);
 	spin_unlock(&nfs_client_lock);
 	if (ret == -EAGAIN)
 		goto retry;
@@ -173,6 +173,7 @@ 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 = cl_init->net;
 
 #ifdef CONFIG_NFS_V4
 	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
@@ -191,7 +192,6 @@ 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;
 
@@ -236,16 +236,20 @@ static void nfs4_shutdown_client(struct nfs_client *clp)
 }
 
 /* idr_remove_all is not needed as all id's are removed by nfs_put_client */
-void nfs_cleanup_cb_ident_idr(void)
+void nfs_cleanup_cb_ident_idr(struct net *net)
 {
-	idr_destroy(&cb_ident_idr);
+	struct nfs_net *nn = net_generic(net, nfs_net_id);
+
+	idr_destroy(&nn->cb_ident_idr);
 }
 
 /* nfs_client_lock held */
 static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 {
+	struct nfs_net *nn = net_generic(clp->net, nfs_net_id);
+
 	if (clp->cl_cb_ident)
-		idr_remove(&cb_ident_idr, clp->cl_cb_ident);
+		idr_remove(&nn->cb_ident_idr, clp->cl_cb_ident);
 }
 
 static void pnfs_init_server(struct nfs_server *server)
@@ -263,7 +267,7 @@ static void nfs4_shutdown_client(struct nfs_client *clp)
 {
 }
 
-void nfs_cleanup_cb_ident_idr(void)
+void nfs_cleanup_cb_ident_idr(struct net *net)
 {
 }
 
@@ -1203,12 +1207,13 @@ struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
  * Find a client by callback identifier
  */
 struct nfs_client *
-nfs4_find_client_ident(int cb_ident)
+nfs4_find_client_ident(struct net *net, int cb_ident)
 {
 	struct nfs_client *clp;
+	struct nfs_net *nn = net_generic(net, nfs_net_id);
 
 	spin_lock(&nfs_client_lock);
-	clp = idr_find(&cb_ident_idr, cb_ident);
+	clp = idr_find(&nn->cb_ident_idr, cb_ident);
 	if (clp)
 		atomic_inc(&clp->cl_count);
 	spin_unlock(&nfs_client_lock);
@@ -1765,6 +1770,9 @@ void nfs_clients_init(struct net *net)
 
 	INIT_LIST_HEAD(&nn->nfs_client_list);
 	INIT_LIST_HEAD(&nn->nfs_volume_list);
+#ifdef CONFIG_NFS_V4
+	idr_init(&nn->cb_ident_idr);
+#endif
 }
 
 #ifdef CONFIG_PROC_FS

fs/nfs/inode.c

@@ -1565,6 +1565,7 @@ static int nfs_net_init(struct net *net)
 static void nfs_net_exit(struct net *net)
 {
 	nfs_dns_resolver_cache_destroy(net);
+	nfs_cleanup_cb_ident_idr(net);
 }
 
 static struct pernet_operations nfs_net_ops = {
@@ -1674,7 +1675,6 @@ static void __exit exit_nfs_fs(void)
 #ifdef CONFIG_PROC_FS
 	rpc_proc_unregister(&init_net, "nfs");
 #endif
-	nfs_cleanup_cb_ident_idr();
 	unregister_nfs_fs();
 	nfs_fs_proc_exit();
 	nfsiod_stop();

fs/nfs/internal.h

@@ -148,9 +148,9 @@ extern void nfs_umount(const struct nfs_mount_request *info);
 extern const struct rpc_program nfs_program;
 extern void nfs_clients_init(struct net *net);
 
-extern void nfs_cleanup_cb_ident_idr(void);
+extern void nfs_cleanup_cb_ident_idr(struct net *);
 extern void nfs_put_client(struct nfs_client *);
-extern struct nfs_client *nfs4_find_client_ident(int);
+extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
 extern struct nfs_client *
 nfs4_find_client_sessionid(const struct sockaddr *, struct nfs4_sessionid *);
 extern struct nfs_server *nfs_create_server(

fs/nfs/netns.h

@@ -9,6 +9,9 @@ struct nfs_net {
 	struct rpc_pipe *bl_device_pipe;
 	struct list_head nfs_client_list;
 	struct list_head nfs_volume_list;
+#ifdef CONFIG_NFS_V4
+	struct idr cb_ident_idr; /* Protected by nfs_client_lock */
+#endif
 };
 
 extern int nfs_net_id;