1 files changed, 29 insertions, 14 deletions

diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index ba3019f5934c..864c51e4b400 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -57,6 +57,11 @@ unsigned int nfs_idmap_cache_timeout = 600;
 static const struct cred *id_resolver_cache;
 static struct key_type key_type_id_resolver_legacy;
 
+struct idmap {
+	struct rpc_pipe		*idmap_pipe;
+	struct key_construction	*idmap_key_cons;
+	struct mutex		idmap_mutex;
+};
 
 /**
  * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
@@ -310,9 +315,11 @@ static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
 					    name, namelen, type, data,
 					    data_size, NULL);
 	if (ret < 0) {
+		mutex_lock(&idmap->idmap_mutex);
 		ret = nfs_idmap_request_key(&key_type_id_resolver_legacy,
 					    name, namelen, type, data,
 					    data_size, idmap);
+		mutex_unlock(&idmap->idmap_mutex);
 	}
 	return ret;
 }
@@ -354,11 +361,6 @@ static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *typ
 /* idmap classic begins here */
 module_param(nfs_idmap_cache_timeout, int, 0644);
 
-struct idmap {
-	struct rpc_pipe		*idmap_pipe;
-	struct key_construction	*idmap_key_cons;
-};
-
 enum {
 	Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
 };
@@ -415,7 +417,7 @@ static int __nfs_idmap_register(struct dentry *dir,
 static void nfs_idmap_unregister(struct nfs_client *clp,
 				      struct rpc_pipe *pipe)
 {
-	struct net *net = clp->net;
+	struct net *net = clp->cl_net;
 	struct super_block *pipefs_sb;
 
 	pipefs_sb = rpc_get_sb_net(net);
@@ -429,7 +431,7 @@ static int nfs_idmap_register(struct nfs_client *clp,
 				   struct idmap *idmap,
 				   struct rpc_pipe *pipe)
 {
-	struct net *net = clp->net;
+	struct net *net = clp->cl_net;
 	struct super_block *pipefs_sb;
 	int err = 0;
 
@@ -469,6 +471,7 @@ nfs_idmap_new(struct nfs_client *clp)
 		return error;
 	}
 	idmap->idmap_pipe = pipe;
+	mutex_init(&idmap->idmap_mutex);
 
 	clp->cl_idmap = idmap;
 	return 0;
@@ -530,9 +533,25 @@ static struct nfs_client *nfs_get_client_for_event(struct net *net, int event)
 	struct nfs_net *nn = net_generic(net, nfs_net_id);
 	struct dentry *cl_dentry;
 	struct nfs_client *clp;
+	int err;
 
+restart:
 	spin_lock(&nn->nfs_client_lock);
 	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
+		/* Wait for initialisation to finish */
+		if (clp->cl_cons_state == NFS_CS_INITING) {
+			atomic_inc(&clp->cl_count);
+			spin_unlock(&nn->nfs_client_lock);
+			err = nfs_wait_client_init_complete(clp);
+			nfs_put_client(clp);
+			if (err)
+				return NULL;
+			goto restart;
+		}
+		/* Skip nfs_clients that failed to initialise */
+		if (clp->cl_cons_state < 0)
+			continue;
+		smp_rmb();
 		if (clp->rpc_ops != &nfs_v4_clientops)
 			continue;
 		cl_dentry = clp->cl_idmap->idmap_pipe->dentry;
@@ -640,20 +659,16 @@ static int nfs_idmap_legacy_upcall(struct key_construction *cons,
 	struct idmap_msg *im;
 	struct idmap *idmap = (struct idmap *)aux;
 	struct key *key = cons->key;
-	int ret;
+	int ret = -ENOMEM;
 
 	/* msg and im are freed in idmap_pipe_destroy_msg */
 	msg = kmalloc(sizeof(*msg), GFP_KERNEL);
-	if (IS_ERR(msg)) {
-		ret = PTR_ERR(msg);
+	if (!msg)
 		goto out0;
-	}
 
 	im = kmalloc(sizeof(*im), GFP_KERNEL);
-	if (IS_ERR(im)) {
-		ret = PTR_ERR(im);
+	if (!im)
 		goto out1;
-	}
 
 	ret = nfs_idmap_prepare_message(key->description, im, msg);
 	if (ret < 0)