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/sched.h> 18 #include <linux/nfs_fs.h> 19 20 #ifdef RPC_DEBUG 21 # define NFSDBG_FACILITY NFSDBG_ROOT 22 #endif 23 24 /* 25 #define MOUNT_PROGRAM 100005 26 #define MOUNT_VERSION 1 27 #define MOUNT_MNT 1 28 #define MOUNT_UMNT 3 29 */ 30 31 static struct rpc_clnt * mnt_create(char *, struct sockaddr_in *, 32 int, int); 33 static struct rpc_program mnt_program; 34 35 struct mnt_fhstatus { 36 unsigned int status; 37 struct nfs_fh * fh; 38 }; 39 40 /* 41 * Obtain an NFS file handle for the given host and path 42 */ 43 int 44 nfsroot_mount(struct sockaddr_in *addr, char *path, struct nfs_fh *fh, 45 int version, int protocol) 46 { 47 struct rpc_clnt *mnt_clnt; 48 struct mnt_fhstatus result = { 49 .fh = fh 50 }; 51 struct rpc_message msg = { 52 .rpc_argp = path, 53 .rpc_resp = &result, 54 }; 55 char hostname[32]; 56 int status; 57 58 dprintk("NFS: nfs_mount(%08x:%s)\n", 59 (unsigned)ntohl(addr->sin_addr.s_addr), path); 60 61 sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(addr->sin_addr.s_addr)); 62 mnt_clnt = mnt_create(hostname, addr, version, protocol); 63 if (IS_ERR(mnt_clnt)) 64 return PTR_ERR(mnt_clnt); 65 66 if (version == NFS_MNT3_VERSION) 67 msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT]; 68 else 69 msg.rpc_proc = &mnt_clnt->cl_procinfo[MNTPROC_MNT]; 70 71 status = rpc_call_sync(mnt_clnt, &msg, 0); 72 return status < 0? status : (result.status? -EACCES : 0); 73 } 74 75 static struct rpc_clnt * 76 mnt_create(char *hostname, struct sockaddr_in *srvaddr, int version, 77 int protocol) 78 { 79 struct rpc_create_args args = { 80 .protocol = protocol, 81 .address = (struct sockaddr *)srvaddr, 82 .addrsize = sizeof(*srvaddr), 83 .servername = hostname, 84 .program = &mnt_program, 85 .version = version, 86 .authflavor = RPC_AUTH_UNIX, 87 .flags = (RPC_CLNT_CREATE_ONESHOT | 88 RPC_CLNT_CREATE_INTR), 89 }; 90 91 return rpc_create(&args); 92 } 93 94 /* 95 * XDR encode/decode functions for MOUNT 96 */ 97 static int 98 xdr_encode_dirpath(struct rpc_rqst *req, __be32 *p, const char *path) 99 { 100 p = xdr_encode_string(p, path); 101 102 req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); 103 return 0; 104 } 105 106 static int 107 xdr_decode_fhstatus(struct rpc_rqst *req, __be32 *p, struct mnt_fhstatus *res) 108 { 109 struct nfs_fh *fh = res->fh; 110 111 if ((res->status = ntohl(*p++)) == 0) { 112 fh->size = NFS2_FHSIZE; 113 memcpy(fh->data, p, NFS2_FHSIZE); 114 } 115 return 0; 116 } 117 118 static int 119 xdr_decode_fhstatus3(struct rpc_rqst *req, __be32 *p, struct mnt_fhstatus *res) 120 { 121 struct nfs_fh *fh = res->fh; 122 123 if ((res->status = ntohl(*p++)) == 0) { 124 int size = ntohl(*p++); 125 if (size <= NFS3_FHSIZE) { 126 fh->size = size; 127 memcpy(fh->data, p, size); 128 } else 129 res->status = -EBADHANDLE; 130 } 131 return 0; 132 } 133 134 #define MNT_dirpath_sz (1 + 256) 135 #define MNT_fhstatus_sz (1 + 8) 136 #define MNT_fhstatus3_sz (1 + 16) 137 138 static struct rpc_procinfo mnt_procedures[] = { 139 [MNTPROC_MNT] = { 140 .p_proc = MNTPROC_MNT, 141 .p_encode = (kxdrproc_t) xdr_encode_dirpath, 142 .p_decode = (kxdrproc_t) xdr_decode_fhstatus, 143 .p_arglen = MNT_dirpath_sz, 144 .p_replen = MNT_fhstatus_sz, 145 .p_statidx = MNTPROC_MNT, 146 .p_name = "MOUNT", 147 }, 148 }; 149 150 static struct rpc_procinfo mnt3_procedures[] = { 151 [MOUNTPROC3_MNT] = { 152 .p_proc = MOUNTPROC3_MNT, 153 .p_encode = (kxdrproc_t) xdr_encode_dirpath, 154 .p_decode = (kxdrproc_t) xdr_decode_fhstatus3, 155 .p_arglen = MNT_dirpath_sz, 156 .p_replen = MNT_fhstatus3_sz, 157 .p_statidx = MOUNTPROC3_MNT, 158 .p_name = "MOUNT", 159 }, 160 }; 161 162 163 static struct rpc_version mnt_version1 = { 164 .number = 1, 165 .nrprocs = 2, 166 .procs = mnt_procedures 167 }; 168 169 static struct rpc_version mnt_version3 = { 170 .number = 3, 171 .nrprocs = 2, 172 .procs = mnt3_procedures 173 }; 174 175 static struct rpc_version * mnt_version[] = { 176 NULL, 177 &mnt_version1, 178 NULL, 179 &mnt_version3, 180 }; 181 182 static struct rpc_stat mnt_stats; 183 184 static struct rpc_program mnt_program = { 185 .name = "mount", 186 .number = NFS_MNT_PROGRAM, 187 .nrvers = ARRAY_SIZE(mnt_version), 188 .version = mnt_version, 189 .stats = &mnt_stats, 190 }; 191