1 /* 2 * linux/fs/nfsd/nfs4callback.c 3 * 4 * Copyright (c) 2001 The Regents of the University of Michigan. 5 * All rights reserved. 6 * 7 * Kendrick Smith <kmsmith@umich.edu> 8 * Andy Adamson <andros@umich.edu> 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its 20 * contributors may be used to endorse or promote products derived 21 * from this software without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 26 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 28 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 30 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 #include <linux/module.h> 37 #include <linux/list.h> 38 #include <linux/inet.h> 39 #include <linux/errno.h> 40 #include <linux/delay.h> 41 #include <linux/sched.h> 42 #include <linux/kthread.h> 43 #include <linux/sunrpc/xdr.h> 44 #include <linux/sunrpc/svc.h> 45 #include <linux/sunrpc/clnt.h> 46 #include <linux/nfsd/nfsd.h> 47 #include <linux/nfsd/state.h> 48 #include <linux/sunrpc/sched.h> 49 #include <linux/nfs4.h> 50 51 #define NFSDDBG_FACILITY NFSDDBG_PROC 52 53 #define NFSPROC4_CB_NULL 0 54 #define NFSPROC4_CB_COMPOUND 1 55 56 /* declarations */ 57 static const struct rpc_call_ops nfs4_cb_null_ops; 58 59 /* Index of predefined Linux callback client operations */ 60 61 enum { 62 NFSPROC4_CLNT_CB_NULL = 0, 63 NFSPROC4_CLNT_CB_RECALL, 64 }; 65 66 enum nfs_cb_opnum4 { 67 OP_CB_RECALL = 4, 68 }; 69 70 #define NFS4_MAXTAGLEN 20 71 72 #define NFS4_enc_cb_null_sz 0 73 #define NFS4_dec_cb_null_sz 0 74 #define cb_compound_enc_hdr_sz 4 75 #define cb_compound_dec_hdr_sz (3 + (NFS4_MAXTAGLEN >> 2)) 76 #define op_enc_sz 1 77 #define op_dec_sz 2 78 #define enc_nfs4_fh_sz (1 + (NFS4_FHSIZE >> 2)) 79 #define enc_stateid_sz (NFS4_STATEID_SIZE >> 2) 80 #define NFS4_enc_cb_recall_sz (cb_compound_enc_hdr_sz + \ 81 1 + enc_stateid_sz + \ 82 enc_nfs4_fh_sz) 83 84 #define NFS4_dec_cb_recall_sz (cb_compound_dec_hdr_sz + \ 85 op_dec_sz) 86 87 /* 88 * Generic encode routines from fs/nfs/nfs4xdr.c 89 */ 90 static inline __be32 * 91 xdr_writemem(__be32 *p, const void *ptr, int nbytes) 92 { 93 int tmp = XDR_QUADLEN(nbytes); 94 if (!tmp) 95 return p; 96 p[tmp-1] = 0; 97 memcpy(p, ptr, nbytes); 98 return p + tmp; 99 } 100 101 #define WRITE32(n) *p++ = htonl(n) 102 #define WRITEMEM(ptr,nbytes) do { \ 103 p = xdr_writemem(p, ptr, nbytes); \ 104 } while (0) 105 #define RESERVE_SPACE(nbytes) do { \ 106 p = xdr_reserve_space(xdr, nbytes); \ 107 if (!p) dprintk("NFSD: RESERVE_SPACE(%d) failed in function %s\n", (int) (nbytes), __func__); \ 108 BUG_ON(!p); \ 109 } while (0) 110 111 /* 112 * Generic decode routines from fs/nfs/nfs4xdr.c 113 */ 114 #define DECODE_TAIL \ 115 status = 0; \ 116 out: \ 117 return status; \ 118 xdr_error: \ 119 dprintk("NFSD: xdr error! (%s:%d)\n", __FILE__, __LINE__); \ 120 status = -EIO; \ 121 goto out 122 123 #define READ32(x) (x) = ntohl(*p++) 124 #define READ64(x) do { \ 125 (x) = (u64)ntohl(*p++) << 32; \ 126 (x) |= ntohl(*p++); \ 127 } while (0) 128 #define READTIME(x) do { \ 129 p++; \ 130 (x.tv_sec) = ntohl(*p++); \ 131 (x.tv_nsec) = ntohl(*p++); \ 132 } while (0) 133 #define READ_BUF(nbytes) do { \ 134 p = xdr_inline_decode(xdr, nbytes); \ 135 if (!p) { \ 136 dprintk("NFSD: %s: reply buffer overflowed in line %d.\n", \ 137 __func__, __LINE__); \ 138 return -EIO; \ 139 } \ 140 } while (0) 141 142 struct nfs4_cb_compound_hdr { 143 int status; 144 u32 ident; 145 u32 nops; 146 u32 taglen; 147 char * tag; 148 }; 149 150 static struct { 151 int stat; 152 int errno; 153 } nfs_cb_errtbl[] = { 154 { NFS4_OK, 0 }, 155 { NFS4ERR_PERM, EPERM }, 156 { NFS4ERR_NOENT, ENOENT }, 157 { NFS4ERR_IO, EIO }, 158 { NFS4ERR_NXIO, ENXIO }, 159 { NFS4ERR_ACCESS, EACCES }, 160 { NFS4ERR_EXIST, EEXIST }, 161 { NFS4ERR_XDEV, EXDEV }, 162 { NFS4ERR_NOTDIR, ENOTDIR }, 163 { NFS4ERR_ISDIR, EISDIR }, 164 { NFS4ERR_INVAL, EINVAL }, 165 { NFS4ERR_FBIG, EFBIG }, 166 { NFS4ERR_NOSPC, ENOSPC }, 167 { NFS4ERR_ROFS, EROFS }, 168 { NFS4ERR_MLINK, EMLINK }, 169 { NFS4ERR_NAMETOOLONG, ENAMETOOLONG }, 170 { NFS4ERR_NOTEMPTY, ENOTEMPTY }, 171 { NFS4ERR_DQUOT, EDQUOT }, 172 { NFS4ERR_STALE, ESTALE }, 173 { NFS4ERR_BADHANDLE, EBADHANDLE }, 174 { NFS4ERR_BAD_COOKIE, EBADCOOKIE }, 175 { NFS4ERR_NOTSUPP, ENOTSUPP }, 176 { NFS4ERR_TOOSMALL, ETOOSMALL }, 177 { NFS4ERR_SERVERFAULT, ESERVERFAULT }, 178 { NFS4ERR_BADTYPE, EBADTYPE }, 179 { NFS4ERR_LOCKED, EAGAIN }, 180 { NFS4ERR_RESOURCE, EREMOTEIO }, 181 { NFS4ERR_SYMLINK, ELOOP }, 182 { NFS4ERR_OP_ILLEGAL, EOPNOTSUPP }, 183 { NFS4ERR_DEADLOCK, EDEADLK }, 184 { -1, EIO } 185 }; 186 187 static int 188 nfs_cb_stat_to_errno(int stat) 189 { 190 int i; 191 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 192 if (nfs_cb_errtbl[i].stat == stat) 193 return nfs_cb_errtbl[i].errno; 194 } 195 /* If we cannot translate the error, the recovery routines should 196 * handle it. 197 * Note: remaining NFSv4 error codes have values > 10000, so should 198 * not conflict with native Linux error codes. 199 */ 200 return stat; 201 } 202 203 /* 204 * XDR encode 205 */ 206 207 static int 208 encode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr) 209 { 210 __be32 * p; 211 212 RESERVE_SPACE(16); 213 WRITE32(0); /* tag length is always 0 */ 214 WRITE32(NFS4_MINOR_VERSION); 215 WRITE32(hdr->ident); 216 WRITE32(hdr->nops); 217 return 0; 218 } 219 220 static int 221 encode_cb_recall(struct xdr_stream *xdr, struct nfs4_cb_recall *cb_rec) 222 { 223 __be32 *p; 224 int len = cb_rec->cbr_fhlen; 225 226 RESERVE_SPACE(12+sizeof(cb_rec->cbr_stateid) + len); 227 WRITE32(OP_CB_RECALL); 228 WRITEMEM(&cb_rec->cbr_stateid, sizeof(stateid_t)); 229 WRITE32(cb_rec->cbr_trunc); 230 WRITE32(len); 231 WRITEMEM(cb_rec->cbr_fhval, len); 232 return 0; 233 } 234 235 static int 236 nfs4_xdr_enc_cb_null(struct rpc_rqst *req, __be32 *p) 237 { 238 struct xdr_stream xdrs, *xdr = &xdrs; 239 240 xdr_init_encode(&xdrs, &req->rq_snd_buf, p); 241 RESERVE_SPACE(0); 242 return 0; 243 } 244 245 static int 246 nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, __be32 *p, struct nfs4_cb_recall *args) 247 { 248 struct xdr_stream xdr; 249 struct nfs4_cb_compound_hdr hdr = { 250 .ident = args->cbr_ident, 251 .nops = 1, 252 }; 253 254 xdr_init_encode(&xdr, &req->rq_snd_buf, p); 255 encode_cb_compound_hdr(&xdr, &hdr); 256 return (encode_cb_recall(&xdr, args)); 257 } 258 259 260 static int 261 decode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr){ 262 __be32 *p; 263 264 READ_BUF(8); 265 READ32(hdr->status); 266 READ32(hdr->taglen); 267 READ_BUF(hdr->taglen + 4); 268 hdr->tag = (char *)p; 269 p += XDR_QUADLEN(hdr->taglen); 270 READ32(hdr->nops); 271 return 0; 272 } 273 274 static int 275 decode_cb_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected) 276 { 277 __be32 *p; 278 u32 op; 279 int32_t nfserr; 280 281 READ_BUF(8); 282 READ32(op); 283 if (op != expected) { 284 dprintk("NFSD: decode_cb_op_hdr: Callback server returned " 285 " operation %d but we issued a request for %d\n", 286 op, expected); 287 return -EIO; 288 } 289 READ32(nfserr); 290 if (nfserr != NFS_OK) 291 return -nfs_cb_stat_to_errno(nfserr); 292 return 0; 293 } 294 295 static int 296 nfs4_xdr_dec_cb_null(struct rpc_rqst *req, __be32 *p) 297 { 298 return 0; 299 } 300 301 static int 302 nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, __be32 *p) 303 { 304 struct xdr_stream xdr; 305 struct nfs4_cb_compound_hdr hdr; 306 int status; 307 308 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p); 309 status = decode_cb_compound_hdr(&xdr, &hdr); 310 if (status) 311 goto out; 312 status = decode_cb_op_hdr(&xdr, OP_CB_RECALL); 313 out: 314 return status; 315 } 316 317 /* 318 * RPC procedure tables 319 */ 320 #define PROC(proc, call, argtype, restype) \ 321 [NFSPROC4_CLNT_##proc] = { \ 322 .p_proc = NFSPROC4_CB_##call, \ 323 .p_encode = (kxdrproc_t) nfs4_xdr_##argtype, \ 324 .p_decode = (kxdrproc_t) nfs4_xdr_##restype, \ 325 .p_arglen = NFS4_##argtype##_sz, \ 326 .p_replen = NFS4_##restype##_sz, \ 327 .p_statidx = NFSPROC4_CB_##call, \ 328 .p_name = #proc, \ 329 } 330 331 static struct rpc_procinfo nfs4_cb_procedures[] = { 332 PROC(CB_NULL, NULL, enc_cb_null, dec_cb_null), 333 PROC(CB_RECALL, COMPOUND, enc_cb_recall, dec_cb_recall), 334 }; 335 336 static struct rpc_version nfs_cb_version4 = { 337 .number = 1, 338 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 339 .procs = nfs4_cb_procedures 340 }; 341 342 static struct rpc_version * nfs_cb_version[] = { 343 NULL, 344 &nfs_cb_version4, 345 }; 346 347 static struct rpc_program cb_program; 348 349 static struct rpc_stat cb_stats = { 350 .program = &cb_program 351 }; 352 353 #define NFS4_CALLBACK 0x40000000 354 static struct rpc_program cb_program = { 355 .name = "nfs4_cb", 356 .number = NFS4_CALLBACK, 357 .nrvers = ARRAY_SIZE(nfs_cb_version), 358 .version = nfs_cb_version, 359 .stats = &cb_stats, 360 }; 361 362 /* Reference counting, callback cleanup, etc., all look racy as heck. 363 * And why is cb_set an atomic? */ 364 365 static int do_probe_callback(void *data) 366 { 367 struct nfs4_client *clp = data; 368 struct sockaddr_in addr; 369 struct nfs4_callback *cb = &clp->cl_callback; 370 struct rpc_timeout timeparms = { 371 .to_initval = (NFSD_LEASE_TIME/4) * HZ, 372 .to_retries = 5, 373 .to_maxval = (NFSD_LEASE_TIME/2) * HZ, 374 .to_exponential = 1, 375 }; 376 struct rpc_create_args args = { 377 .protocol = IPPROTO_TCP, 378 .address = (struct sockaddr *)&addr, 379 .addrsize = sizeof(addr), 380 .timeout = &timeparms, 381 .program = &cb_program, 382 .version = nfs_cb_version[1]->number, 383 .authflavor = RPC_AUTH_UNIX, /* XXX: need AUTH_GSS... */ 384 .flags = (RPC_CLNT_CREATE_NOPING), 385 }; 386 struct rpc_message msg = { 387 .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL], 388 .rpc_argp = clp, 389 }; 390 struct rpc_clnt *client; 391 int status; 392 393 /* Initialize address */ 394 memset(&addr, 0, sizeof(addr)); 395 addr.sin_family = AF_INET; 396 addr.sin_port = htons(cb->cb_port); 397 addr.sin_addr.s_addr = htonl(cb->cb_addr); 398 399 /* Initialize rpc_stat */ 400 memset(args.program->stats, 0, sizeof(struct rpc_stat)); 401 402 /* Create RPC client */ 403 client = rpc_create(&args); 404 if (IS_ERR(client)) { 405 dprintk("NFSD: couldn't create callback client\n"); 406 status = PTR_ERR(client); 407 goto out_err; 408 } 409 410 status = rpc_call_sync(client, &msg, RPC_TASK_SOFT); 411 412 if (status) 413 goto out_release_client; 414 415 cb->cb_client = client; 416 atomic_set(&cb->cb_set, 1); 417 put_nfs4_client(clp); 418 return 0; 419 out_release_client: 420 rpc_shutdown_client(client); 421 out_err: 422 put_nfs4_client(clp); 423 dprintk("NFSD: warning: no callback path to client %.*s\n", 424 (int)clp->cl_name.len, clp->cl_name.data); 425 return status; 426 } 427 428 /* 429 * Set up the callback client and put a NFSPROC4_CB_NULL on the wire... 430 */ 431 void 432 nfsd4_probe_callback(struct nfs4_client *clp) 433 { 434 struct task_struct *t; 435 436 BUG_ON(atomic_read(&clp->cl_callback.cb_set)); 437 438 /* the task holds a reference to the nfs4_client struct */ 439 atomic_inc(&clp->cl_count); 440 441 t = kthread_run(do_probe_callback, clp, "nfs4_cb_probe"); 442 443 if (IS_ERR(t)) 444 atomic_dec(&clp->cl_count); 445 446 return; 447 } 448 449 /* 450 * called with dp->dl_count inc'ed. 451 * nfs4_lock_state() may or may not have been called. 452 */ 453 void 454 nfsd4_cb_recall(struct nfs4_delegation *dp) 455 { 456 struct nfs4_client *clp = dp->dl_client; 457 struct rpc_clnt *clnt = clp->cl_callback.cb_client; 458 struct nfs4_cb_recall *cbr = &dp->dl_recall; 459 struct rpc_message msg = { 460 .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL], 461 .rpc_argp = cbr, 462 }; 463 int retries = 1; 464 int status = 0; 465 466 cbr->cbr_trunc = 0; /* XXX need to implement truncate optimization */ 467 cbr->cbr_dp = dp; 468 469 status = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT); 470 while (retries--) { 471 switch (status) { 472 case -EIO: 473 /* Network partition? */ 474 atomic_set(&clp->cl_callback.cb_set, 0); 475 case -EBADHANDLE: 476 case -NFS4ERR_BAD_STATEID: 477 /* Race: client probably got cb_recall 478 * before open reply granting delegation */ 479 break; 480 default: 481 goto out_put_cred; 482 } 483 ssleep(2); 484 status = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT); 485 } 486 out_put_cred: 487 /* 488 * Success or failure, now we're either waiting for lease expiration 489 * or deleg_return. 490 */ 491 put_nfs4_client(clp); 492 nfs4_put_delegation(dp); 493 return; 494 } 495