[for-6.11 PATCH 25/29] nfs: implement v4 client support for NFS_LOCALIO_PROGRAM

[Mike Snitzer <snitzer@kernel.org>]

While doing so, factor out nfs_init_localioclient() so it is used by
both nfs3client.c and nfs4client.c

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
---
 fs/nfs/internal.h       | 28 ++++++++++++++++++++--
 fs/nfs/localio.c        |  2 +-
 fs/nfs/nfs3client.c     | 19 +--------------
 fs/nfs/nfs4_fs.h        |  2 ++
 fs/nfs/nfs4client.c     | 23 ++++++++++++++++++
 fs/nfs/nfs4proc.c       |  3 +++
 fs/nfs/nfs4xdr.c        | 53 +++++++++++++++++++++++++++++++++++++++++
 include/linux/nfs_xdr.h |  2 ++
 8 files changed, 111 insertions(+), 21 deletions(-)

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 9f81a94e798c..1b2adca930fa 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -452,7 +452,31 @@ extern void nfs_set_cache_invalid(struct inode *inode, unsigned long flags);
 extern bool nfs_check_cache_invalid(struct inode *, unsigned long);
 extern int nfs_wait_bit_killable(struct wait_bit_key *key, int mode);
 
-#if defined(CONFIG_NFS_V3_LOCALIO)
+#if defined(CONFIG_NFS_V3_LOCALIO) || defined(CONFIG_NFS_V4_LOCALIO)
+/*
+ * Initialise an NFS localio client connection.
+ * Inlined here to allow nfs[34]client.c to share this code.
+ */
+static __always_inline void
+nfs_init_localioclient(struct nfs_client *clp,
+		       const struct rpc_program *program, u32 vers)
+{
+	bool supported = false;
+
+	if (unlikely(!IS_ERR(clp->cl_rpcclient_localio)))
+		goto out;
+	clp->cl_rpcclient_localio = rpc_bind_new_program(clp->cl_rpcclient,
+							program, vers);
+	if (IS_ERR(clp->cl_rpcclient_localio))
+		goto out;
+	/* No errors! Assume that localio is supported */
+	supported = true;
+out:
+	dfprintk_rcu(CLIENT, "%s: server (%s) %s NFS v%u LOCALIO\n", __func__,
+		rpc_peeraddr2str(clp->cl_rpcclient_localio, RPC_DISPLAY_ADDR),
+		(supported ? "supports" : "does not support"), vers);
+}
+
 /* localio.c */
 extern void nfs_local_init(void);
 extern void nfs_local_enable(struct nfs_client *);
@@ -507,7 +531,7 @@ static inline bool nfs_server_is_local(const struct nfs_client *clp)
 {
 	return false;
 }
-#endif /* CONFIG_NFS_V3_LOCALIO */
+#endif /* CONFIG_NFS_V3_LOCALIO || CONFIG_NFS_V4_LOCALIO */
 
 /* super.c */
 extern const struct super_operations nfs_sops;
diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c
index 145708444998..ab92c92f04e5 100644
--- a/fs/nfs/localio.c
+++ b/fs/nfs/localio.c
@@ -269,6 +269,7 @@ void nfs_local_probe(struct nfs_client *clp)
 
 	switch (clp->cl_rpcclient->cl_vers) {
 	case 3:
+	case 4:
 		/*
 		 * Retrieve server's uuid via LOCALIO protocol and verify the
 		 * server with that uuid it is known to be local. This ensures
@@ -280,7 +281,6 @@ void nfs_local_probe(struct nfs_client *clp)
 		if (!nfsd_uuid_is_local(&uuid))
 			return;
 		break;
-	case 4:
 	default:
 		return; /* localio not supported */
 	}
diff --git a/fs/nfs/nfs3client.c b/fs/nfs/nfs3client.c
index c41122ee808c..123e7c1fd339 100644
--- a/fs/nfs/nfs3client.c
+++ b/fs/nfs/nfs3client.c
@@ -152,23 +152,6 @@ const struct rpc_program nfslocalio_program3 = {
  */
 void nfs3_init_localioclient(struct nfs_client *clp)
 {
-	if (unlikely(!IS_ERR(clp->cl_rpcclient_localio)))
-		goto out;
-
-	clp->cl_rpcclient_localio = rpc_bind_new_program(clp->cl_rpcclient,
-							&nfslocalio_program3, 3);
-	if (IS_ERR(clp->cl_rpcclient_localio)) {
-		dprintk_rcu("%s: server (%s) does not support NFS v3 LOCALIO\n", __func__,
-			rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
-		return;
-	}
-out:
-	/* No errors! Assume that localio is supported */
-	dprintk_rcu("%s: server (%s) supports NFS v3 LOCALIO\n", __func__,
-		rpc_peeraddr2str(clp->cl_rpcclient_localio, RPC_DISPLAY_ADDR));
-}
-#else
-void nfs3_init_localioclient(struct nfs_client *clp)
-{
+	nfs_init_localioclient(clp, &nfslocalio_program3, 3);
 }
 #endif /* CONFIG_NFS_V3_LOCALIO */
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 7024230f0d1d..a0a41917dec2 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -538,6 +538,8 @@ extern int nfs4_proc_commit(struct file *dst, __u64 offset, __u32 count, struct
 extern const nfs4_stateid zero_stateid;
 extern const nfs4_stateid invalid_stateid;
 
+extern void nfs4_init_localioclient(struct nfs_client *);
+
 /* nfs4super.c */
 struct nfs_mount_info;
 extern struct nfs_subversion nfs_v4;
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
index 84573df5cf5a..d2f634aa1e1b 100644
--- a/fs/nfs/nfs4client.c
+++ b/fs/nfs/nfs4client.c
@@ -1384,3 +1384,26 @@ int nfs4_update_server(struct nfs_server *server, const char *hostname,
 
 	return nfs_probe_server(server, NFS_FH(d_inode(server->super->s_root)));
 }
+
+#if defined(CONFIG_NFS_V4_LOCALIO)
+static struct rpc_stat		nfslocalio_rpcstat = { &nfslocalio_program4 };
+static const struct rpc_version *nfslocalio_version[] = {
+	[4]			= &nfslocalio_version4,
+};
+
+const struct rpc_program nfslocalio_program4 = {
+	.name			= "nfslocalio",
+	.number			= NFS_LOCALIO_PROGRAM,
+	.nrvers			= ARRAY_SIZE(nfslocalio_version),
+	.version		= nfslocalio_version,
+	.stats			= &nfslocalio_rpcstat,
+};
+
+/*
+ * Initialise an NFSv4 localio client connection
+ */
+void nfs4_init_localioclient(struct nfs_client *clp)
+{
+	nfs_init_localioclient(clp, &nfslocalio_program4, 4);
+}
+#endif /* CONFIG_NFS_V4_LOCALIO */
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index c93c12063b3a..060bc8dbee61 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -10745,6 +10745,9 @@ const struct nfs_rpc_ops nfs_v4_clientops = {
 	.discover_trunking = nfs4_discover_trunking,
 	.enable_swap	= nfs4_enable_swap,
 	.disable_swap	= nfs4_disable_swap,
+#if defined(CONFIG_NFS_V4_LOCALIO)
+	.init_localioclient = nfs4_init_localioclient,
+#endif
 };
 
 static const struct xattr_handler nfs4_xattr_nfs4_acl_handler = {
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 1416099dfcd1..e6f3556a320e 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -7728,3 +7728,56 @@ const struct rpc_version nfs_version4 = {
 	.procs			= nfs4_procedures,
 	.counts			= nfs_version4_counts,
 };
+
+#if defined(CONFIG_NFS_V4_LOCALIO)
+
+#define NFS4_filename_sz	(1+(NFS4_MAXNAMLEN>>2))
+#define LOCALIO4_getuuidres_sz	(1+NFS4_filename_sz)
+
+static void nfs4_xdr_enc_getuuidargs(struct rpc_rqst *req,
+				struct xdr_stream *xdr,
+				const void *data)
+{
+	/* void function */
+}
+
+static inline int nfs4_decode_getuuidresok(struct xdr_stream *xdr,
+					struct nfs_getuuidres *result)
+{
+	return decode_opaque_inline(xdr, &result->len, (char **)&result->uuid);
+}
+
+static int nfs4_xdr_dec_getuuidres(struct rpc_rqst *req,
+				struct xdr_stream *xdr,
+				void *result)
+{
+	// FIXME: need proper handling that isn't abusing nfs_opnum4
+	int error = decode_op_hdr(xdr, LOCALIOPROC_GETUUID);
+	if (unlikely(error))
+		goto out;
+	error = nfs4_decode_getuuidresok(xdr, result);
+out:
+	return error;
+}
+
+static const struct rpc_procinfo nfs4_localio_procedures[] = {
+	[LOCALIOPROC_GETUUID] = {
+		.p_proc = LOCALIOPROC_GETUUID,
+		.p_encode = nfs4_xdr_enc_getuuidargs,
+		.p_decode = nfs4_xdr_dec_getuuidres,
+		.p_arglen = 1,
+		.p_replen = LOCALIO4_getuuidres_sz,
+		.p_statidx = LOCALIOPROC_GETUUID,
+		.p_name = "GETUUID",
+	},
+};
+
+static unsigned int nfs4_localio_counts[ARRAY_SIZE(nfs4_localio_procedures)];
+const struct rpc_version nfslocalio_version4 = {
+	.number			= 4,
+	.nrprocs		= ARRAY_SIZE(nfs4_localio_procedures),
+	.procs			= nfs4_localio_procedures,
+	.counts			= nfs4_localio_counts,
+};
+
+#endif  /* CONFIG_NFS_V4_LOCALIO */
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 9a030e9bd9cf..b6a16eca4664 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1842,5 +1842,7 @@ extern const struct rpc_program nfsacl_program;
 
 extern const struct rpc_version nfslocalio_version3;
 extern const struct rpc_program nfslocalio_program3;
+extern const struct rpc_version nfslocalio_version4;
+extern const struct rpc_program nfslocalio_program4;
 
 #endif
-- 
2.44.0