aboutsummaryrefslogtreecommitdiffstats
path: root/fs/nfs/mount_clnt.c
blob: af45a374d56f6e8b7be3d1e1d87f232b1a82a304 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
/*
 * In-kernel MOUNT protocol client
 *
 * Copyright (C) 1997, Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/types.h>
#include <linux/socket.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/uio.h>
#include <linux/net.h>
#include <linux/in.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/sched.h>
#include <linux/nfs_fs.h>
#include "internal.h"

#ifdef RPC_DEBUG
# define NFSDBG_FACILITY	NFSDBG_MOUNT
#endif

/*
 * Defined by RFC 1094, section A.5
 */
enum {
	MOUNTPROC_NULL		= 0,
	MOUNTPROC_MNT		= 1,
	MOUNTPROC_DUMP		= 2,
	MOUNTPROC_UMNT		= 3,
	MOUNTPROC_UMNTALL	= 4,
	MOUNTPROC_EXPORT	= 5,
};

/*
 * Defined by RFC 1813, section 5.2
 */
enum {
	MOUNTPROC3_NULL		= 0,
	MOUNTPROC3_MNT		= 1,
	MOUNTPROC3_DUMP		= 2,
	MOUNTPROC3_UMNT		= 3,
	MOUNTPROC3_UMNTALL	= 4,
	MOUNTPROC3_EXPORT	= 5,
};

static struct rpc_program	mnt_program;

struct mnt_fhstatus {
	u32 status;
	struct nfs_fh *fh;
};

/**
 * nfs_mount - Obtain an NFS file handle for the given host and path
 * @info: pointer to mount request arguments
 *
 * Uses default timeout parameters specified by underlying transport.
 */
int nfs_mount(struct nfs_mount_request *info)
{
	struct mnt_fhstatus	result = {
		.fh		= info->fh
	};
	struct rpc_message msg	= {
		.rpc_argp	= info->dirpath,
		.rpc_resp	= &result,
	};
	struct rpc_create_args args = {
		.protocol	= info->protocol,
		.address	= info->sap,
		.addrsize	= info->salen,
		.servername	= info->hostname,
		.program	= &mnt_program,
		.version	= info->version,
		.authflavor	= RPC_AUTH_UNIX,
	};
	struct rpc_clnt		*mnt_clnt;
	int			status;

	dprintk("NFS: sending MNT request for %s:%s\n",
		(info->hostname ? info->hostname : "server"),
			info->dirpath);

	if (info->noresvport)
		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;

	mnt_clnt = rpc_create(&args);
	if (IS_ERR(mnt_clnt))
		goto out_clnt_err;

	if (info->version == NFS_MNT3_VERSION)
		msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT];
	else
		msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT];

	status = rpc_call_sync(mnt_clnt, &msg, 0);
	rpc_shutdown_client(mnt_clnt);

	if (status < 0)
		goto out_call_err;
	if (result.status != 0)
		goto out_mnt_err;

	dprintk("NFS: MNT request succeeded\n");
	status = 0;

out:
	return status;

out_clnt_err:
	status = PTR_ERR(mnt_clnt);
	dprintk("NFS: failed to create RPC client, status=%d\n", status);
	goto out;

out_call_err:
	dprintk("NFS: failed to start MNT request, status=%d\n", status);
	goto out;

out_mnt_err:
	dprintk("NFS: MNT server returned result %d\n", result.status);
	status = nfs_stat_to_errno(result.status);
	goto out;
}

/*
 * XDR encode/decode functions for MOUNT
 */
static int xdr_encode_dirpath(struct rpc_rqst *req, __be32 *p,
			      const char *path)
{
	p = xdr_encode_string(p, path);

	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

static int xdr_decode_fhstatus(struct rpc_rqst *req, __be32 *p,
			       struct mnt_fhstatus *res)
{
	struct nfs_fh *fh = res->fh;

	if ((res->status = ntohl(*p++)) == 0) {
		fh->size = NFS2_FHSIZE;
		memcpy(fh->data, p, NFS2_FHSIZE);
	}
	return 0;
}

static int xdr_decode_fhstatus3(struct rpc_rqst *req, __be32 *p,
				struct mnt_fhstatus *res)
{
	struct nfs_fh *fh = res->fh;
	unsigned size;

	if ((res->status = ntohl(*p++)) == 0) {
		size = ntohl(*p++);
		if (size <= NFS3_FHSIZE && size != 0) {
			fh->size = size;
			memcpy(fh->data, p, size);
		} else
			res->status = -EBADHANDLE;
	}
	return 0;
}

#define MNT_dirpath_sz		(1 + 256)
#define MNT_fhstatus_sz		(1 + 8)
#define MNT_fhstatus3_sz	(1 + 16)

static struct rpc_procinfo mnt_procedures[] = {
	[MOUNTPROC_MNT] = {
		.p_proc		= MOUNTPROC_MNT,
		.p_encode	= (kxdrproc_t) xdr_encode_dirpath,
		.p_decode	= (kxdrproc_t) xdr_decode_fhstatus,
		.p_arglen	= MNT_dirpath_sz,
		.p_replen	= MNT_fhstatus_sz,
		.p_statidx	= MOUNTPROC_MNT,
		.p_name		= "MOUNT",
	},
};

static struct rpc_procinfo mnt3_procedures[] = {
	[MOUNTPROC3_MNT] = {
		.p_proc		= MOUNTPROC3_MNT,
		.p_encode	= (kxdrproc_t) xdr_encode_dirpath,
		.p_decode	= (kxdrproc_t) xdr_decode_fhstatus3,
		.p_arglen	= MNT_dirpath_sz,
		.p_replen	= MNT_fhstatus3_sz,
		.p_statidx	= MOUNTPROC3_MNT,
		.p_name		= "MOUNT",
	},
};


static struct rpc_version mnt_version1 = {
	.number		= 1,
	.nrprocs	= 2,
	.procs		= mnt_procedures,
};

static struct rpc_version mnt_version3 = {
	.number		= 3,
	.nrprocs	= 2,
	.procs		= mnt3_procedures,
};

static struct rpc_version *mnt_version[] = {
	NULL,
	&mnt_version1,
	NULL,
	&mnt_version3,
};

static struct rpc_stat mnt_stats;

static struct rpc_program mnt_program = {
	.name		= "mount",
	.number		= NFS_MNT_PROGRAM,
	.nrvers		= ARRAY_SIZE(mnt_version),
	.version	= mnt_version,
	.stats		= &mnt_stats,
};