1 /* 2 * Copyright (c) 2001 The Regents of the University of Michigan. 3 * All rights reserved. 4 * 5 * Kendrick Smith <kmsmith@umich.edu> 6 * Andy Adamson <andros@umich.edu> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the University nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 22 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 24 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 28 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 29 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 31 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <linux/sunrpc/clnt.h> 35 #include <linux/sunrpc/svc_xprt.h> 36 #include <linux/slab.h> 37 #include "nfsd.h" 38 #include "state.h" 39 40 #define NFSDDBG_FACILITY NFSDDBG_PROC 41 42 #define NFSPROC4_CB_NULL 0 43 #define NFSPROC4_CB_COMPOUND 1 44 45 /* Index of predefined Linux callback client operations */ 46 47 enum { 48 NFSPROC4_CLNT_CB_NULL = 0, 49 NFSPROC4_CLNT_CB_RECALL, 50 NFSPROC4_CLNT_CB_SEQUENCE, 51 }; 52 53 enum nfs_cb_opnum4 { 54 OP_CB_RECALL = 4, 55 OP_CB_SEQUENCE = 11, 56 }; 57 58 #define NFS4_MAXTAGLEN 20 59 60 #define NFS4_enc_cb_null_sz 0 61 #define NFS4_dec_cb_null_sz 0 62 #define cb_compound_enc_hdr_sz 4 63 #define cb_compound_dec_hdr_sz (3 + (NFS4_MAXTAGLEN >> 2)) 64 #define sessionid_sz (NFS4_MAX_SESSIONID_LEN >> 2) 65 #define cb_sequence_enc_sz (sessionid_sz + 4 + \ 66 1 /* no referring calls list yet */) 67 #define cb_sequence_dec_sz (op_dec_sz + sessionid_sz + 4) 68 69 #define op_enc_sz 1 70 #define op_dec_sz 2 71 #define enc_nfs4_fh_sz (1 + (NFS4_FHSIZE >> 2)) 72 #define enc_stateid_sz (NFS4_STATEID_SIZE >> 2) 73 #define NFS4_enc_cb_recall_sz (cb_compound_enc_hdr_sz + \ 74 cb_sequence_enc_sz + \ 75 1 + enc_stateid_sz + \ 76 enc_nfs4_fh_sz) 77 78 #define NFS4_dec_cb_recall_sz (cb_compound_dec_hdr_sz + \ 79 cb_sequence_dec_sz + \ 80 op_dec_sz) 81 82 /* 83 * Generic encode routines from fs/nfs/nfs4xdr.c 84 */ 85 static inline __be32 * 86 xdr_writemem(__be32 *p, const void *ptr, int nbytes) 87 { 88 int tmp = XDR_QUADLEN(nbytes); 89 if (!tmp) 90 return p; 91 p[tmp-1] = 0; 92 memcpy(p, ptr, nbytes); 93 return p + tmp; 94 } 95 96 #define WRITE32(n) *p++ = htonl(n) 97 #define WRITEMEM(ptr,nbytes) do { \ 98 p = xdr_writemem(p, ptr, nbytes); \ 99 } while (0) 100 #define RESERVE_SPACE(nbytes) do { \ 101 p = xdr_reserve_space(xdr, nbytes); \ 102 if (!p) dprintk("NFSD: RESERVE_SPACE(%d) failed in function %s\n", (int) (nbytes), __func__); \ 103 BUG_ON(!p); \ 104 } while (0) 105 106 /* 107 * Generic decode routines from fs/nfs/nfs4xdr.c 108 */ 109 #define DECODE_TAIL \ 110 status = 0; \ 111 out: \ 112 return status; \ 113 xdr_error: \ 114 dprintk("NFSD: xdr error! (%s:%d)\n", __FILE__, __LINE__); \ 115 status = -EIO; \ 116 goto out 117 118 #define READ32(x) (x) = ntohl(*p++) 119 #define READ64(x) do { \ 120 (x) = (u64)ntohl(*p++) << 32; \ 121 (x) |= ntohl(*p++); \ 122 } while (0) 123 #define READTIME(x) do { \ 124 p++; \ 125 (x.tv_sec) = ntohl(*p++); \ 126 (x.tv_nsec) = ntohl(*p++); \ 127 } while (0) 128 #define READ_BUF(nbytes) do { \ 129 p = xdr_inline_decode(xdr, nbytes); \ 130 if (!p) { \ 131 dprintk("NFSD: %s: reply buffer overflowed in line %d.\n", \ 132 __func__, __LINE__); \ 133 return -EIO; \ 134 } \ 135 } while (0) 136 137 struct nfs4_cb_compound_hdr { 138 /* args */ 139 u32 ident; /* minorversion 0 only */ 140 u32 nops; 141 __be32 *nops_p; 142 u32 minorversion; 143 /* res */ 144 int status; 145 }; 146 147 static struct { 148 int stat; 149 int errno; 150 } nfs_cb_errtbl[] = { 151 { NFS4_OK, 0 }, 152 { NFS4ERR_PERM, EPERM }, 153 { NFS4ERR_NOENT, ENOENT }, 154 { NFS4ERR_IO, EIO }, 155 { NFS4ERR_NXIO, ENXIO }, 156 { NFS4ERR_ACCESS, EACCES }, 157 { NFS4ERR_EXIST, EEXIST }, 158 { NFS4ERR_XDEV, EXDEV }, 159 { NFS4ERR_NOTDIR, ENOTDIR }, 160 { NFS4ERR_ISDIR, EISDIR }, 161 { NFS4ERR_INVAL, EINVAL }, 162 { NFS4ERR_FBIG, EFBIG }, 163 { NFS4ERR_NOSPC, ENOSPC }, 164 { NFS4ERR_ROFS, EROFS }, 165 { NFS4ERR_MLINK, EMLINK }, 166 { NFS4ERR_NAMETOOLONG, ENAMETOOLONG }, 167 { NFS4ERR_NOTEMPTY, ENOTEMPTY }, 168 { NFS4ERR_DQUOT, EDQUOT }, 169 { NFS4ERR_STALE, ESTALE }, 170 { NFS4ERR_BADHANDLE, EBADHANDLE }, 171 { NFS4ERR_BAD_COOKIE, EBADCOOKIE }, 172 { NFS4ERR_NOTSUPP, ENOTSUPP }, 173 { NFS4ERR_TOOSMALL, ETOOSMALL }, 174 { NFS4ERR_SERVERFAULT, ESERVERFAULT }, 175 { NFS4ERR_BADTYPE, EBADTYPE }, 176 { NFS4ERR_LOCKED, EAGAIN }, 177 { NFS4ERR_RESOURCE, EREMOTEIO }, 178 { NFS4ERR_SYMLINK, ELOOP }, 179 { NFS4ERR_OP_ILLEGAL, EOPNOTSUPP }, 180 { NFS4ERR_DEADLOCK, EDEADLK }, 181 { -1, EIO } 182 }; 183 184 static int 185 nfs_cb_stat_to_errno(int stat) 186 { 187 int i; 188 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 189 if (nfs_cb_errtbl[i].stat == stat) 190 return nfs_cb_errtbl[i].errno; 191 } 192 /* If we cannot translate the error, the recovery routines should 193 * handle it. 194 * Note: remaining NFSv4 error codes have values > 10000, so should 195 * not conflict with native Linux error codes. 196 */ 197 return stat; 198 } 199 200 /* 201 * XDR encode 202 */ 203 204 static void 205 encode_stateid(struct xdr_stream *xdr, stateid_t *sid) 206 { 207 __be32 *p; 208 209 RESERVE_SPACE(sizeof(stateid_t)); 210 WRITE32(sid->si_generation); 211 WRITEMEM(&sid->si_opaque, sizeof(stateid_opaque_t)); 212 } 213 214 static void 215 encode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr) 216 { 217 __be32 * p; 218 219 RESERVE_SPACE(16); 220 WRITE32(0); /* tag length is always 0 */ 221 WRITE32(hdr->minorversion); 222 WRITE32(hdr->ident); 223 hdr->nops_p = p; 224 WRITE32(hdr->nops); 225 } 226 227 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr) 228 { 229 *hdr->nops_p = htonl(hdr->nops); 230 } 231 232 static void 233 encode_cb_recall(struct xdr_stream *xdr, struct nfs4_delegation *dp, 234 struct nfs4_cb_compound_hdr *hdr) 235 { 236 __be32 *p; 237 int len = dp->dl_fh.fh_size; 238 239 RESERVE_SPACE(4); 240 WRITE32(OP_CB_RECALL); 241 encode_stateid(xdr, &dp->dl_stateid); 242 RESERVE_SPACE(8 + (XDR_QUADLEN(len) << 2)); 243 WRITE32(0); /* truncate optimization not implemented */ 244 WRITE32(len); 245 WRITEMEM(&dp->dl_fh.fh_base, len); 246 hdr->nops++; 247 } 248 249 static void 250 encode_cb_sequence(struct xdr_stream *xdr, struct nfsd4_callback *cb, 251 struct nfs4_cb_compound_hdr *hdr) 252 { 253 __be32 *p; 254 struct nfsd4_session *ses = cb->cb_clp->cl_cb_session; 255 256 if (hdr->minorversion == 0) 257 return; 258 259 RESERVE_SPACE(1 + NFS4_MAX_SESSIONID_LEN + 20); 260 261 WRITE32(OP_CB_SEQUENCE); 262 WRITEMEM(ses->se_sessionid.data, NFS4_MAX_SESSIONID_LEN); 263 WRITE32(ses->se_cb_seq_nr); 264 WRITE32(0); /* slotid, always 0 */ 265 WRITE32(0); /* highest slotid always 0 */ 266 WRITE32(0); /* cachethis always 0 */ 267 WRITE32(0); /* FIXME: support referring_call_lists */ 268 hdr->nops++; 269 } 270 271 static int 272 nfs4_xdr_enc_cb_null(struct rpc_rqst *req, __be32 *p) 273 { 274 struct xdr_stream xdrs, *xdr = &xdrs; 275 276 xdr_init_encode(&xdrs, &req->rq_snd_buf, p); 277 RESERVE_SPACE(0); 278 return 0; 279 } 280 281 static int 282 nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, __be32 *p, 283 struct nfsd4_callback *cb) 284 { 285 struct xdr_stream xdr; 286 struct nfs4_delegation *args = cb->cb_op; 287 struct nfs4_cb_compound_hdr hdr = { 288 .ident = cb->cb_clp->cl_cb_ident, 289 .minorversion = cb->cb_minorversion, 290 }; 291 292 xdr_init_encode(&xdr, &req->rq_snd_buf, p); 293 encode_cb_compound_hdr(&xdr, &hdr); 294 encode_cb_sequence(&xdr, cb, &hdr); 295 encode_cb_recall(&xdr, args, &hdr); 296 encode_cb_nops(&hdr); 297 return 0; 298 } 299 300 301 static int 302 decode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr){ 303 __be32 *p; 304 u32 taglen; 305 306 READ_BUF(8); 307 READ32(hdr->status); 308 /* We've got no use for the tag; ignore it: */ 309 READ32(taglen); 310 READ_BUF(taglen + 4); 311 p += XDR_QUADLEN(taglen); 312 READ32(hdr->nops); 313 return 0; 314 } 315 316 static int 317 decode_cb_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected) 318 { 319 __be32 *p; 320 u32 op; 321 int32_t nfserr; 322 323 READ_BUF(8); 324 READ32(op); 325 if (op != expected) { 326 dprintk("NFSD: decode_cb_op_hdr: Callback server returned " 327 " operation %d but we issued a request for %d\n", 328 op, expected); 329 return -EIO; 330 } 331 READ32(nfserr); 332 if (nfserr != NFS_OK) 333 return -nfs_cb_stat_to_errno(nfserr); 334 return 0; 335 } 336 337 /* 338 * Our current back channel implmentation supports a single backchannel 339 * with a single slot. 340 */ 341 static int 342 decode_cb_sequence(struct xdr_stream *xdr, struct nfsd4_callback *cb, 343 struct rpc_rqst *rqstp) 344 { 345 struct nfsd4_session *ses = cb->cb_clp->cl_cb_session; 346 struct nfs4_sessionid id; 347 int status; 348 u32 dummy; 349 __be32 *p; 350 351 if (cb->cb_minorversion == 0) 352 return 0; 353 354 status = decode_cb_op_hdr(xdr, OP_CB_SEQUENCE); 355 if (status) 356 return status; 357 358 /* 359 * If the server returns different values for sessionID, slotID or 360 * sequence number, the server is looney tunes. 361 */ 362 status = -ESERVERFAULT; 363 364 READ_BUF(NFS4_MAX_SESSIONID_LEN + 16); 365 memcpy(id.data, p, NFS4_MAX_SESSIONID_LEN); 366 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN); 367 if (memcmp(id.data, ses->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) { 368 dprintk("%s Invalid session id\n", __func__); 369 goto out; 370 } 371 READ32(dummy); 372 if (dummy != ses->se_cb_seq_nr) { 373 dprintk("%s Invalid sequence number\n", __func__); 374 goto out; 375 } 376 READ32(dummy); /* slotid must be 0 */ 377 if (dummy != 0) { 378 dprintk("%s Invalid slotid\n", __func__); 379 goto out; 380 } 381 /* FIXME: process highest slotid and target highest slotid */ 382 status = 0; 383 out: 384 return status; 385 } 386 387 388 static int 389 nfs4_xdr_dec_cb_null(struct rpc_rqst *req, __be32 *p) 390 { 391 return 0; 392 } 393 394 static int 395 nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, __be32 *p, 396 struct nfsd4_callback *cb) 397 { 398 struct xdr_stream xdr; 399 struct nfs4_cb_compound_hdr hdr; 400 int status; 401 402 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p); 403 status = decode_cb_compound_hdr(&xdr, &hdr); 404 if (status) 405 goto out; 406 if (cb) { 407 status = decode_cb_sequence(&xdr, cb, rqstp); 408 if (status) 409 goto out; 410 } 411 status = decode_cb_op_hdr(&xdr, OP_CB_RECALL); 412 out: 413 return status; 414 } 415 416 /* 417 * RPC procedure tables 418 */ 419 #define PROC(proc, call, argtype, restype) \ 420 [NFSPROC4_CLNT_##proc] = { \ 421 .p_proc = NFSPROC4_CB_##call, \ 422 .p_encode = (kxdrproc_t) nfs4_xdr_##argtype, \ 423 .p_decode = (kxdrproc_t) nfs4_xdr_##restype, \ 424 .p_arglen = NFS4_##argtype##_sz, \ 425 .p_replen = NFS4_##restype##_sz, \ 426 .p_statidx = NFSPROC4_CB_##call, \ 427 .p_name = #proc, \ 428 } 429 430 static struct rpc_procinfo nfs4_cb_procedures[] = { 431 PROC(CB_NULL, NULL, enc_cb_null, dec_cb_null), 432 PROC(CB_RECALL, COMPOUND, enc_cb_recall, dec_cb_recall), 433 }; 434 435 static struct rpc_version nfs_cb_version4 = { 436 /* 437 * Note on the callback rpc program version number: despite language in rfc 438 * 5661 section 18.36.3 requiring servers to use 4 in this field, the 439 * official xdr descriptions for both 4.0 and 4.1 specify version 1, and 440 * in practice that appears to be what implementations use. The section 441 * 18.36.3 language is expected to be fixed in an erratum. 442 */ 443 .number = 1, 444 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 445 .procs = nfs4_cb_procedures 446 }; 447 448 static struct rpc_version * nfs_cb_version[] = { 449 &nfs_cb_version4, 450 }; 451 452 static struct rpc_program cb_program; 453 454 static struct rpc_stat cb_stats = { 455 .program = &cb_program 456 }; 457 458 #define NFS4_CALLBACK 0x40000000 459 static struct rpc_program cb_program = { 460 .name = "nfs4_cb", 461 .number = NFS4_CALLBACK, 462 .nrvers = ARRAY_SIZE(nfs_cb_version), 463 .version = nfs_cb_version, 464 .stats = &cb_stats, 465 .pipe_dir_name = "/nfsd4_cb", 466 }; 467 468 static int max_cb_time(void) 469 { 470 return max(nfsd4_lease/10, (time_t)1) * HZ; 471 } 472 473 /* Reference counting, callback cleanup, etc., all look racy as heck. 474 * And why is cl_cb_set an atomic? */ 475 476 int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn) 477 { 478 struct rpc_timeout timeparms = { 479 .to_initval = max_cb_time(), 480 .to_retries = 0, 481 }; 482 struct rpc_create_args args = { 483 .net = &init_net, 484 .address = (struct sockaddr *) &conn->cb_addr, 485 .addrsize = conn->cb_addrlen, 486 .timeout = &timeparms, 487 .program = &cb_program, 488 .version = 0, 489 .authflavor = clp->cl_flavor, 490 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), 491 }; 492 struct rpc_clnt *client; 493 494 if (clp->cl_minorversion == 0) { 495 if (!clp->cl_principal && (clp->cl_flavor >= RPC_AUTH_GSS_KRB5)) 496 return -EINVAL; 497 args.client_name = clp->cl_principal; 498 args.prognumber = conn->cb_prog, 499 args.protocol = XPRT_TRANSPORT_TCP; 500 clp->cl_cb_ident = conn->cb_ident; 501 } else { 502 args.bc_xprt = conn->cb_xprt; 503 args.prognumber = clp->cl_cb_session->se_cb_prog; 504 args.protocol = XPRT_TRANSPORT_BC_TCP; 505 } 506 /* Create RPC client */ 507 client = rpc_create(&args); 508 if (IS_ERR(client)) { 509 dprintk("NFSD: couldn't create callback client: %ld\n", 510 PTR_ERR(client)); 511 return PTR_ERR(client); 512 } 513 clp->cl_cb_client = client; 514 return 0; 515 516 } 517 518 static void warn_no_callback_path(struct nfs4_client *clp, int reason) 519 { 520 dprintk("NFSD: warning: no callback path to client %.*s: error %d\n", 521 (int)clp->cl_name.len, clp->cl_name.data, reason); 522 } 523 524 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata) 525 { 526 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 527 528 if (task->tk_status) 529 warn_no_callback_path(clp, task->tk_status); 530 else 531 atomic_set(&clp->cl_cb_set, 1); 532 } 533 534 static const struct rpc_call_ops nfsd4_cb_probe_ops = { 535 /* XXX: release method to ensure we set the cb channel down if 536 * necessary on early failure? */ 537 .rpc_call_done = nfsd4_cb_probe_done, 538 }; 539 540 static struct rpc_cred *callback_cred; 541 542 int set_callback_cred(void) 543 { 544 if (callback_cred) 545 return 0; 546 callback_cred = rpc_lookup_machine_cred(); 547 if (!callback_cred) 548 return -ENOMEM; 549 return 0; 550 } 551 552 static struct workqueue_struct *callback_wq; 553 554 static void do_probe_callback(struct nfs4_client *clp) 555 { 556 struct nfsd4_callback *cb = &clp->cl_cb_null; 557 558 cb->cb_op = NULL; 559 cb->cb_clp = clp; 560 561 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL]; 562 cb->cb_msg.rpc_argp = NULL; 563 cb->cb_msg.rpc_resp = NULL; 564 cb->cb_msg.rpc_cred = callback_cred; 565 566 cb->cb_ops = &nfsd4_cb_probe_ops; 567 568 queue_work(callback_wq, &cb->cb_work); 569 } 570 571 /* 572 * Poke the callback thread to process any updates to the callback 573 * parameters, and send a null probe. 574 */ 575 void nfsd4_probe_callback(struct nfs4_client *clp) 576 { 577 set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_cb_flags); 578 do_probe_callback(clp); 579 } 580 581 void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn) 582 { 583 BUG_ON(atomic_read(&clp->cl_cb_set)); 584 585 spin_lock(&clp->cl_lock); 586 memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn)); 587 spin_unlock(&clp->cl_lock); 588 } 589 590 /* 591 * There's currently a single callback channel slot. 592 * If the slot is available, then mark it busy. Otherwise, set the 593 * thread for sleeping on the callback RPC wait queue. 594 */ 595 static int nfsd41_cb_setup_sequence(struct nfs4_client *clp, 596 struct rpc_task *task) 597 { 598 u32 *ptr = (u32 *)clp->cl_cb_session->se_sessionid.data; 599 int status = 0; 600 601 dprintk("%s: %u:%u:%u:%u\n", __func__, 602 ptr[0], ptr[1], ptr[2], ptr[3]); 603 604 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 605 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL); 606 dprintk("%s slot is busy\n", __func__); 607 status = -EAGAIN; 608 goto out; 609 } 610 out: 611 dprintk("%s status=%d\n", __func__, status); 612 return status; 613 } 614 615 /* 616 * TODO: cb_sequence should support referring call lists, cachethis, multiple 617 * slots, and mark callback channel down on communication errors. 618 */ 619 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata) 620 { 621 struct nfsd4_callback *cb = calldata; 622 struct nfs4_delegation *dp = container_of(cb, struct nfs4_delegation, dl_recall); 623 struct nfs4_client *clp = dp->dl_client; 624 u32 minorversion = clp->cl_minorversion; 625 int status = 0; 626 627 cb->cb_minorversion = minorversion; 628 if (minorversion) { 629 status = nfsd41_cb_setup_sequence(clp, task); 630 if (status) { 631 if (status != -EAGAIN) { 632 /* terminate rpc task */ 633 task->tk_status = status; 634 task->tk_action = NULL; 635 } 636 return; 637 } 638 } 639 rpc_call_start(task); 640 } 641 642 static void nfsd4_cb_done(struct rpc_task *task, void *calldata) 643 { 644 struct nfsd4_callback *cb = calldata; 645 struct nfs4_delegation *dp = container_of(cb, struct nfs4_delegation, dl_recall); 646 struct nfs4_client *clp = dp->dl_client; 647 648 dprintk("%s: minorversion=%d\n", __func__, 649 clp->cl_minorversion); 650 651 if (clp->cl_minorversion) { 652 /* No need for lock, access serialized in nfsd4_cb_prepare */ 653 ++clp->cl_cb_session->se_cb_seq_nr; 654 clear_bit(0, &clp->cl_cb_slot_busy); 655 rpc_wake_up_next(&clp->cl_cb_waitq); 656 dprintk("%s: freed slot, new seqid=%d\n", __func__, 657 clp->cl_cb_session->se_cb_seq_nr); 658 659 /* We're done looking into the sequence information */ 660 task->tk_msg.rpc_resp = NULL; 661 } 662 } 663 664 665 static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata) 666 { 667 struct nfsd4_callback *cb = calldata; 668 struct nfs4_delegation *dp = container_of(cb, struct nfs4_delegation, dl_recall); 669 struct nfs4_client *clp = dp->dl_client; 670 struct rpc_clnt *current_rpc_client = clp->cl_cb_client; 671 672 nfsd4_cb_done(task, calldata); 673 674 if (current_rpc_client == NULL) { 675 /* We're shutting down; give up. */ 676 /* XXX: err, or is it ok just to fall through 677 * and rpc_restart_call? */ 678 return; 679 } 680 681 switch (task->tk_status) { 682 case 0: 683 return; 684 case -EBADHANDLE: 685 case -NFS4ERR_BAD_STATEID: 686 /* Race: client probably got cb_recall 687 * before open reply granting delegation */ 688 break; 689 default: 690 /* Network partition? */ 691 atomic_set(&clp->cl_cb_set, 0); 692 warn_no_callback_path(clp, task->tk_status); 693 if (current_rpc_client != task->tk_client) { 694 /* queue a callback on the new connection: */ 695 atomic_inc(&dp->dl_count); 696 nfsd4_cb_recall(dp); 697 return; 698 } 699 } 700 if (dp->dl_retries--) { 701 rpc_delay(task, 2*HZ); 702 task->tk_status = 0; 703 rpc_restart_call_prepare(task); 704 return; 705 } else { 706 atomic_set(&clp->cl_cb_set, 0); 707 warn_no_callback_path(clp, task->tk_status); 708 } 709 } 710 711 static void nfsd4_cb_recall_release(void *calldata) 712 { 713 struct nfsd4_callback *cb = calldata; 714 struct nfs4_delegation *dp = container_of(cb, struct nfs4_delegation, dl_recall); 715 716 nfs4_put_delegation(dp); 717 } 718 719 static const struct rpc_call_ops nfsd4_cb_recall_ops = { 720 .rpc_call_prepare = nfsd4_cb_prepare, 721 .rpc_call_done = nfsd4_cb_recall_done, 722 .rpc_release = nfsd4_cb_recall_release, 723 }; 724 725 int nfsd4_create_callback_queue(void) 726 { 727 callback_wq = create_singlethread_workqueue("nfsd4_callbacks"); 728 if (!callback_wq) 729 return -ENOMEM; 730 return 0; 731 } 732 733 void nfsd4_destroy_callback_queue(void) 734 { 735 destroy_workqueue(callback_wq); 736 } 737 738 /* must be called under the state lock */ 739 void nfsd4_shutdown_callback(struct nfs4_client *clp) 740 { 741 set_bit(NFSD4_CLIENT_KILL, &clp->cl_cb_flags); 742 /* 743 * Note this won't actually result in a null callback; 744 * instead, nfsd4_do_callback_rpc() will detect the killed 745 * client, destroy the rpc client, and stop: 746 */ 747 do_probe_callback(clp); 748 flush_workqueue(callback_wq); 749 } 750 751 void nfsd4_release_cb(struct nfsd4_callback *cb) 752 { 753 if (cb->cb_ops->rpc_release) 754 cb->cb_ops->rpc_release(cb); 755 } 756 757 void nfsd4_process_cb_update(struct nfsd4_callback *cb) 758 { 759 struct nfs4_cb_conn conn; 760 struct nfs4_client *clp = cb->cb_clp; 761 int err; 762 763 /* 764 * This is either an update, or the client dying; in either case, 765 * kill the old client: 766 */ 767 if (clp->cl_cb_client) { 768 rpc_shutdown_client(clp->cl_cb_client); 769 clp->cl_cb_client = NULL; 770 } 771 if (test_bit(NFSD4_CLIENT_KILL, &clp->cl_cb_flags)) 772 return; 773 spin_lock(&clp->cl_lock); 774 /* 775 * Only serialized callback code is allowed to clear these 776 * flags; main nfsd code can only set them: 777 */ 778 BUG_ON(!clp->cl_cb_flags); 779 clear_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_cb_flags); 780 memcpy(&conn, &cb->cb_clp->cl_cb_conn, sizeof(struct nfs4_cb_conn)); 781 spin_unlock(&clp->cl_lock); 782 783 err = setup_callback_client(clp, &conn); 784 if (err) 785 warn_no_callback_path(clp, err); 786 } 787 788 void nfsd4_do_callback_rpc(struct work_struct *w) 789 { 790 struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, cb_work); 791 struct nfs4_client *clp = cb->cb_clp; 792 struct rpc_clnt *clnt; 793 794 if (clp->cl_cb_flags) 795 nfsd4_process_cb_update(cb); 796 797 clnt = clp->cl_cb_client; 798 if (!clnt) { 799 /* Callback channel broken, or client killed; give up: */ 800 nfsd4_release_cb(cb); 801 return; 802 } 803 rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN, 804 cb->cb_ops, cb); 805 } 806 807 void nfsd4_cb_recall(struct nfs4_delegation *dp) 808 { 809 struct nfsd4_callback *cb = &dp->dl_recall; 810 811 dp->dl_retries = 1; 812 cb->cb_op = dp; 813 cb->cb_clp = dp->dl_client; 814 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL]; 815 cb->cb_msg.rpc_argp = cb; 816 cb->cb_msg.rpc_resp = cb; 817 cb->cb_msg.rpc_cred = callback_cred; 818 819 cb->cb_ops = &nfsd4_cb_recall_ops; 820 dp->dl_retries = 1; 821 822 queue_work(callback_wq, &dp->dl_recall.cb_work); 823 } 824