NFSv4: use the (more efficient) NFSv2/v3-like XDR scheme for looking up the

mountpoint.

fs/nfs/nfs4proc.c

@@ -54,7 +54,7 @@
 #define GET_OP(cp,name)		&cp->ops[cp->req_nops].u.name
 #define OPNUM(cp)		cp->ops[cp->req_nops].opnum
 
-static int nfs4_proc_fsinfo(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *);
+static int nfs4_do_fsinfo(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *);
 static int nfs4_async_handle_error(struct rpc_task *, struct nfs_server *);
 extern u32 *nfs4_decode_dirent(u32 *p, struct nfs_entry *entry, int plus);
 extern struct rpc_procinfo nfs4_procedures[];
@@ -252,17 +252,6 @@ nfs4_setup_link(struct nfs4_compound *cp, struct qstr *name,
 	cp->req_nops++;
 }
 
-static void
-nfs4_setup_lookup(struct nfs4_compound *cp, struct qstr *q)
-{
-	struct nfs4_lookup *lookup = GET_OP(cp, lookup);
-
-	lookup->lo_name = q;
-
-	OPNUM(cp) = OP_LOOKUP;
-	cp->req_nops++;
-}
-
 static void
 nfs4_setup_putfh(struct nfs4_compound *cp, struct nfs_fh *fhandle)
 {
@@ -274,13 +263,6 @@ nfs4_setup_putfh(struct nfs4_compound *cp, struct nfs_fh *fhandle)
 	cp->req_nops++;
 }
 
-static void
-nfs4_setup_putrootfh(struct nfs4_compound *cp)
-{
-        OPNUM(cp) = OP_PUTROOTFH;
-        cp->req_nops++;
-}
-
 static void
 nfs4_setup_readdir(struct nfs4_compound *cp, u64 cookie, u32 *verifier,
 		     struct page **pages, unsigned int bufsize, struct dentry *dentry)
@@ -821,30 +803,60 @@ nfs4_open_revalidate(struct inode *dir, struct dentry *dentry, int openflags)
 	return 0;
 }
 
-static int
-nfs4_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
-		   struct nfs_fsinfo *info)
+static int nfs4_lookup_root(struct nfs_server *server, struct nfs_fh *fhandle,
+		struct nfs_fsinfo *info)
+{
+	struct nfs_fattr *	fattr = info->fattr;
+	struct nfs4_lookup_root_arg args = {
+		.bitmask = nfs4_fattr_bitmap,
+	};
+	struct nfs4_lookup_res res = {
+		.server = server,
+		.fattr = fattr,
+		.fh = fhandle,
+	};
+	struct rpc_message msg = {
+		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LOOKUP_ROOT],
+		.rpc_argp = &args,
+		.rpc_resp = &res,
+	};
+	fattr->valid = 0;
+	return rpc_call_sync(server->client, &msg, 0);
+}
+
+static int nfs4_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
+		struct nfs_fsinfo *info)
 {
-	struct nfs4_compound	compound;
-	struct nfs4_op		ops[4];
 	struct nfs_fattr *	fattr = info->fattr;
 	unsigned char *		p;
 	struct qstr		q;
-	int			status;
+	struct nfs4_lookup_arg args = {
+		.dir_fh = fhandle,
+		.name = &q,
+		.bitmask = nfs4_fattr_bitmap,
+	};
+	struct nfs4_lookup_res res = {
+		.server = server,
+		.fattr = fattr,
+		.fh = fhandle,
+	};
+	struct rpc_message msg = {
+		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LOOKUP],
+		.rpc_argp = &args,
+		.rpc_resp = &res,
+	};
+	int status;
 
 	/*
 	 * Now we do a separate LOOKUP for each component of the mount path.
 	 * The LOOKUPs are done separately so that we can conveniently
 	 * catch an ERR_WRONGSEC if it occurs along the way...
 	 */
-	p = server->mnt_path;
-	fattr->valid = 0;
-	nfs4_setup_compound(&compound, ops, server, "getrootfh");
-	nfs4_setup_putrootfh(&compound);
-	nfs4_setup_getattr(&compound, fattr);
-	nfs4_setup_getfh(&compound, fhandle);
-	if ((status = nfs4_call_compound(&compound, NULL, 0)))
+	status = nfs4_lookup_root(server, fhandle, info);
+	if (status)
 		goto out;
+
+	p = server->mnt_path;
 	for (;;) {
 		while (*p == '/')
 			p++;
@@ -856,12 +868,7 @@ nfs4_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
 		q.len = p - q.name;
 
 		fattr->valid = 0;
-		nfs4_setup_compound(&compound, ops, server, "mount");
-		nfs4_setup_putfh(&compound, fhandle);
-		nfs4_setup_lookup(&compound, &q);
-		nfs4_setup_getattr(&compound, fattr);
-		nfs4_setup_getfh(&compound, fhandle);
-		status = nfs4_call_compound(&compound, NULL, 0);
+		status = rpc_call_sync(server->client, &msg, 0);
 		if (!status)
 			continue;
 		if (status == -ENOENT) {
@@ -870,10 +877,10 @@ nfs4_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
 		}
 		break;
 	}
+	if (status == 0)
+		status = nfs4_do_fsinfo(server, fhandle, info);
 out:
-	if (status)
-		return nfs4_map_errors(status);
-	return nfs4_proc_fsinfo(server, fhandle, info);
+	return nfs4_map_errors(status);
 }
 
 static int nfs4_proc_getattr(struct inode *inode, struct nfs_fattr *fattr)
@@ -1468,9 +1475,8 @@ nfs4_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle,
 	return nfs4_map_errors(nfs4_call_compound(&compound, NULL, 0));
 }
 
-static int
-nfs4_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
-		 struct nfs_fsinfo *fsinfo)
+static int nfs4_do_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
+		struct nfs_fsinfo *fsinfo)
 {
 	struct rpc_message msg = {
 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_FSINFO],
@@ -1481,6 +1487,12 @@ nfs4_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
 	return nfs4_map_errors(rpc_call_sync(server->client, &msg, 0));
 }
 
+static int nfs4_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle, struct nfs_fsinfo *fsinfo)
+{
+	fsinfo->fattr->valid = 0;
+	return nfs4_map_errors(nfs4_do_fsinfo(server, fhandle, fsinfo));
+}
+
 static int
 nfs4_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
 		   struct nfs_pathconf *pathconf)

fs/nfs/nfs4xdr.c

@@ -262,6 +262,14 @@ static int nfs_stat_to_errno(int);
 				op_decode_hdr_maxsz + \
 				decode_getattr_maxsz + \
 				decode_getfh_maxsz)
+#define NFS4_enc_lookup_root_sz (compound_encode_hdr_maxsz + \
+				encode_putrootfh_maxsz + \
+				encode_getattr_maxsz + \
+				encode_getfh_maxsz)
+#define NFS4_dec_lookup_root_sz (compound_decode_hdr_maxsz + \
+				decode_putrootfh_maxsz + \
+				decode_getattr_maxsz + \
+				decode_getfh_maxsz)
 
 
 
@@ -1088,15 +1096,9 @@ encode_compound(struct xdr_stream *xdr, struct nfs4_compound *cp, struct rpc_rqs
 		case OP_LINK:
 			status = encode_link(xdr, &cp->ops[i].u.link);
 			break;
-		case OP_LOOKUP:
-			status = encode_lookup(xdr, cp->ops[i].u.lookup.lo_name);
-			break;
 		case OP_PUTFH:
 			status = encode_putfh(xdr, cp->ops[i].u.putfh.pf_fhandle);
 			break;
-		case OP_PUTROOTFH:
-			status = encode_putrootfh(xdr);
-			break;
 		case OP_READDIR:
 			status = encode_readdir(xdr, &cp->ops[i].u.readdir, req);
 			break;
@@ -1185,6 +1187,27 @@ static int nfs4_xdr_enc_lookup(struct rpc_rqst *req, uint32_t *p, const struct n
 	return status;
 }
 
+/*
+ * Encode LOOKUP_ROOT request
+ */
+static int nfs4_xdr_enc_lookup_root(struct rpc_rqst *req, uint32_t *p, const struct nfs4_lookup_root_arg *args)
+{
+	struct xdr_stream xdr;
+	struct compound_hdr hdr = {
+		.nops = 3,
+	};
+	int status;
+
+	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
+	encode_compound_hdr(&xdr, &hdr);
+	if ((status = encode_putrootfh(&xdr)) != 0)
+		goto out;
+	if ((status = encode_getfh(&xdr)) == 0)
+		status = encode_getfattr(&xdr, args->bitmask);
+out:
+	return status;
+}
+
 /*
  * Encode GETATTR request
  */
@@ -2902,15 +2925,9 @@ decode_compound(struct xdr_stream *xdr, struct nfs4_compound *cp, struct rpc_rqs
 		case OP_LINK:
 			status = decode_link(xdr, &op->u.link);
 			break;
-		case OP_LOOKUP:
-			status = decode_lookup(xdr);
-			break;
 		case OP_PUTFH:
 			status = decode_putfh(xdr);
 			break;
-		case OP_PUTROOTFH:
-			status = decode_putrootfh(xdr);
-			break;
 		case OP_READDIR:
 			status = decode_readdir(xdr, req, &op->u.readdir);
 			break;
@@ -3028,6 +3045,26 @@ static int nfs4_xdr_dec_lookup(struct rpc_rqst *rqstp, uint32_t *p, struct nfs4_
 	return status;
 }
 
+/*
+ * Decode LOOKUP_ROOT response
+ */
+static int nfs4_xdr_dec_lookup_root(struct rpc_rqst *rqstp, uint32_t *p, struct nfs4_lookup_res *res)
+{
+	struct xdr_stream xdr;
+	struct compound_hdr hdr;
+	int status;
+	
+	xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
+	if ((status = decode_compound_hdr(&xdr, &hdr)) != 0)
+		goto out;
+	if ((status = decode_putrootfh(&xdr)) != 0)
+		goto out;
+	if ((status = decode_getfh(&xdr, res->fh)) == 0)
+		status = decode_getfattr(&xdr, res->fattr, res->server);
+out:
+	return status;
+}
+
 /*
  * Decode GETATTR response
  */
@@ -3538,6 +3575,7 @@ struct rpc_procinfo	nfs4_procedures[] = {
   PROC(ACCESS,		enc_access,	dec_access),
   PROC(GETATTR,		enc_getattr,	dec_getattr),
   PROC(LOOKUP,		enc_lookup,	dec_lookup),
+  PROC(LOOKUP_ROOT,	enc_lookup_root,	dec_lookup_root),
 };
 
 struct rpc_version		nfs_version4 = {

include/linux/nfs4.h

@@ -306,6 +306,7 @@ enum {
 	NFSPROC4_CLNT_ACCESS,
 	NFSPROC4_CLNT_GETATTR,
 	NFSPROC4_CLNT_LOOKUP,
+	NFSPROC4_CLNT_LOOKUP_ROOT,
 };
 
 #endif

include/linux/nfs_xdr.h

@@ -550,10 +550,6 @@ struct nfs4_link {
 	struct nfs4_change_info *	ln_cinfo;         /* response */
 };
 
-struct nfs4_lookup {
-	struct qstr *			lo_name;          /* request */
-};
-
 struct nfs4_lookup_arg {
 	const struct nfs_fh *		dir_fh;
 	const struct qstr *		name;
@@ -566,6 +562,10 @@ struct nfs4_lookup_res {
 	struct nfs_fh *			fh;
 };
 
+struct nfs4_lookup_root_arg {
+	const u32 *			bitmask;
+};
+
 struct nfs4_open {
 	struct nfs4_client *		op_client_state;  /* request */
 	u32				op_share_access;  /* request */
@@ -644,7 +644,6 @@ struct nfs4_op {
 		struct nfs4_getattr	getattr;
 		struct nfs4_getfh	getfh;
 		struct nfs4_link	link;
-		struct nfs4_lookup	lookup;
 		struct nfs4_open	open;
 		struct nfs4_open_confirm open_confirm;
 		struct nfs4_putfh	putfh;