xref: /openbmc/linux/fs/nfs/mount_clnt.c (revision d5cb9783536a41df9f9cba5b0a1d78047ed787f7)
1 /*
2  * linux/fs/nfs/mount_clnt.c
3  *
4  * MOUNT client to support NFSroot.
5  *
6  * Copyright (C) 1997, Olaf Kirch <okir@monad.swb.de>
7  */
8 
9 #include <linux/types.h>
10 #include <linux/socket.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/uio.h>
14 #include <linux/net.h>
15 #include <linux/in.h>
16 #include <linux/sunrpc/clnt.h>
17 #include <linux/sunrpc/xprt.h>
18 #include <linux/sunrpc/sched.h>
19 #include <linux/nfs_fs.h>
20 
21 #ifdef RPC_DEBUG
22 # define NFSDBG_FACILITY	NFSDBG_ROOT
23 #endif
24 
25 /*
26 #define MOUNT_PROGRAM		100005
27 #define MOUNT_VERSION		1
28 #define MOUNT_MNT		1
29 #define MOUNT_UMNT		3
30  */
31 
32 static struct rpc_clnt *	mnt_create(char *, struct sockaddr_in *,
33 								int, int);
34 static struct rpc_program	mnt_program;
35 
36 struct mnt_fhstatus {
37 	unsigned int		status;
38 	struct nfs_fh *		fh;
39 };
40 
41 /*
42  * Obtain an NFS file handle for the given host and path
43  */
44 int
45 nfsroot_mount(struct sockaddr_in *addr, char *path, struct nfs_fh *fh,
46 		int version, int protocol)
47 {
48 	struct rpc_clnt		*mnt_clnt;
49 	struct mnt_fhstatus	result = {
50 		.fh		= fh
51 	};
52 	char			hostname[32];
53 	int			status;
54 	int			call;
55 
56 	dprintk("NFS:      nfs_mount(%08x:%s)\n",
57 			(unsigned)ntohl(addr->sin_addr.s_addr), path);
58 
59 	sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(addr->sin_addr.s_addr));
60 	mnt_clnt = mnt_create(hostname, addr, version, protocol);
61 	if (IS_ERR(mnt_clnt))
62 		return PTR_ERR(mnt_clnt);
63 
64 	call = (version == NFS_MNT3_VERSION) ? MOUNTPROC3_MNT : MNTPROC_MNT;
65 	status = rpc_call(mnt_clnt, call, path, &result, 0);
66 	return status < 0? status : (result.status? -EACCES : 0);
67 }
68 
69 static struct rpc_clnt *
70 mnt_create(char *hostname, struct sockaddr_in *srvaddr, int version,
71 		int protocol)
72 {
73 	struct rpc_xprt	*xprt;
74 	struct rpc_clnt	*clnt;
75 
76 	xprt = xprt_create_proto(protocol, srvaddr, NULL);
77 	if (IS_ERR(xprt))
78 		return (struct rpc_clnt *)xprt;
79 
80 	clnt = rpc_create_client(xprt, hostname,
81 				&mnt_program, version,
82 				RPC_AUTH_UNIX);
83 	if (!IS_ERR(clnt)) {
84 		clnt->cl_softrtry = 1;
85 		clnt->cl_chatty   = 1;
86 		clnt->cl_oneshot  = 1;
87 		clnt->cl_intr = 1;
88 	}
89 	return clnt;
90 }
91 
92 /*
93  * XDR encode/decode functions for MOUNT
94  */
95 static int
96 xdr_encode_dirpath(struct rpc_rqst *req, u32 *p, const char *path)
97 {
98 	p = xdr_encode_string(p, path);
99 
100 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
101 	return 0;
102 }
103 
104 static int
105 xdr_decode_fhstatus(struct rpc_rqst *req, u32 *p, struct mnt_fhstatus *res)
106 {
107 	struct nfs_fh *fh = res->fh;
108 
109 	if ((res->status = ntohl(*p++)) == 0) {
110 		fh->size = NFS2_FHSIZE;
111 		memcpy(fh->data, p, NFS2_FHSIZE);
112 	}
113 	return 0;
114 }
115 
116 static int
117 xdr_decode_fhstatus3(struct rpc_rqst *req, u32 *p, struct mnt_fhstatus *res)
118 {
119 	struct nfs_fh *fh = res->fh;
120 
121 	if ((res->status = ntohl(*p++)) == 0) {
122 		int size = ntohl(*p++);
123 		if (size <= NFS3_FHSIZE) {
124 			fh->size = size;
125 			memcpy(fh->data, p, size);
126 		} else
127 			res->status = -EBADHANDLE;
128 	}
129 	return 0;
130 }
131 
132 #define MNT_dirpath_sz		(1 + 256)
133 #define MNT_fhstatus_sz		(1 + 8)
134 
135 static struct rpc_procinfo	mnt_procedures[] = {
136 [MNTPROC_MNT] = {
137 	  .p_proc		= MNTPROC_MNT,
138 	  .p_encode		= (kxdrproc_t) xdr_encode_dirpath,
139 	  .p_decode		= (kxdrproc_t) xdr_decode_fhstatus,
140 	  .p_bufsiz		= MNT_dirpath_sz << 2,
141 	},
142 };
143 
144 static struct rpc_procinfo mnt3_procedures[] = {
145 [MOUNTPROC3_MNT] = {
146 	  .p_proc		= MOUNTPROC3_MNT,
147 	  .p_encode		= (kxdrproc_t) xdr_encode_dirpath,
148 	  .p_decode		= (kxdrproc_t) xdr_decode_fhstatus3,
149 	  .p_bufsiz		= MNT_dirpath_sz << 2,
150 	},
151 };
152 
153 
154 static struct rpc_version	mnt_version1 = {
155 		.number		= 1,
156 		.nrprocs 	= 2,
157 		.procs 		= mnt_procedures
158 };
159 
160 static struct rpc_version       mnt_version3 = {
161 		.number		= 3,
162 		.nrprocs	= 2,
163 		.procs		= mnt3_procedures
164 };
165 
166 static struct rpc_version *	mnt_version[] = {
167 	NULL,
168 	&mnt_version1,
169 	NULL,
170 	&mnt_version3,
171 };
172 
173 static struct rpc_stat		mnt_stats;
174 
175 static struct rpc_program	mnt_program = {
176 	.name		= "mount",
177 	.number		= NFS_MNT_PROGRAM,
178 	.nrvers		= sizeof(mnt_version)/sizeof(mnt_version[0]),
179 	.version	= mnt_version,
180 	.stats		= &mnt_stats,
181 };
182