nfs: convert setclientid and exchange_id encoders to use clp->cl_owner_id

...instead of buffers that are part of their arg structs. We already
hold a reference to the client, so we might as well use the allocated
buffer. In the event that we can't allocate the clp->cl_owner_id, then
just return -ENOMEM.

Note too that we switch from a GFP_KERNEL allocation here to GFP_NOFS.
It's possible we could end up trying to do a SETCLIENTID or EXCHANGE_ID
in order to reclaim some memory, and the GFP_KERNEL allocations in the
existing code could cause recursion back into NFS reclaim.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

1 files changed, 16 insertions, 5 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index d689ea37be84..b2afe9556147 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5046,7 +5046,7 @@ int nfs4_proc_setclientid(struct nfs_client *clp, u32 program,
 	struct nfs4_setclientid setclientid = {
 		.sc_verifier = &sc_verifier,
 		.sc_prog = program,
-		.sc_cb_ident = clp->cl_cb_ident,
+		.sc_clnt = clp,
 	};
 	struct rpc_message msg = {
 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SETCLIENTID],
@@ -5076,6 +5076,12 @@ int nfs4_proc_setclientid(struct nfs_client *clp, u32 program,
 				nfs4_init_nonuniform_client_string(clp,
 						setclientid.sc_name,
 						sizeof(setclientid.sc_name));
+
+	if (!clp->cl_owner_id) {
+		status = -ENOMEM;
+		goto out;
+	}
+
 	/* cb_client4 */
 	setclientid.sc_netid_len =
 				nfs4_init_callback_netid(clp,
@@ -5085,9 +5091,9 @@ int nfs4_proc_setclientid(struct nfs_client *clp, u32 program,
 				sizeof(setclientid.sc_uaddr), "%s.%u.%u",
 				clp->cl_ipaddr, port >> 8, port & 255);
 
-	dprintk("NFS call  setclientid auth=%s, '%.*s'\n",
+	dprintk("NFS call  setclientid auth=%s, '%s'\n",
 		clp->cl_rpcclient->cl_auth->au_ops->au_name,
-		setclientid.sc_name_len, setclientid.sc_name);
+		clp->cl_owner_id);
 	task = rpc_run_task(&task_setup_data);
 	if (IS_ERR(task)) {
 		status = PTR_ERR(task);
@@ -6850,9 +6856,14 @@ static int _nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred,
 	nfs4_init_boot_verifier(clp, &verifier);
 	args.id_len = nfs4_init_uniform_client_string(clp, args.id,
 							sizeof(args.id));
-	dprintk("NFS call  exchange_id auth=%s, '%.*s'\n",
+	if (!clp->cl_owner_id) {
+		status = -ENOMEM;
+		goto out;
+	}
+
+	dprintk("NFS call  exchange_id auth=%s, '%s'\n",
 		clp->cl_rpcclient->cl_auth->au_ops->au_name,
-		args.id_len, args.id);
+		clp->cl_owner_id);
 
 	res.server_owner = kzalloc(sizeof(struct nfs41_server_owner),
 					GFP_NOFS);