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/xprt.h> 36 #include <linux/sunrpc/svc_xprt.h> 37 #include <linux/slab.h> 38 #include "nfsd.h" 39 #include "state.h" 40 #include "netns.h" 41 #include "xdr4cb.h" 42 43 #define NFSDDBG_FACILITY NFSDDBG_PROC 44 45 static void nfsd4_mark_cb_fault(struct nfs4_client *, int reason); 46 47 #define NFSPROC4_CB_NULL 0 48 #define NFSPROC4_CB_COMPOUND 1 49 50 /* Index of predefined Linux callback client operations */ 51 52 enum { 53 NFSPROC4_CLNT_CB_NULL = 0, 54 NFSPROC4_CLNT_CB_RECALL, 55 NFSPROC4_CLNT_CB_SEQUENCE, 56 }; 57 58 struct nfs4_cb_compound_hdr { 59 /* args */ 60 u32 ident; /* minorversion 0 only */ 61 u32 nops; 62 __be32 *nops_p; 63 u32 minorversion; 64 /* res */ 65 int status; 66 }; 67 68 /* 69 * Handle decode buffer overflows out-of-line. 70 */ 71 static void print_overflow_msg(const char *func, const struct xdr_stream *xdr) 72 { 73 dprintk("NFS: %s prematurely hit the end of our receive buffer. " 74 "Remaining buffer length is %tu words.\n", 75 func, xdr->end - xdr->p); 76 } 77 78 static __be32 *xdr_encode_empty_array(__be32 *p) 79 { 80 *p++ = xdr_zero; 81 return p; 82 } 83 84 /* 85 * Encode/decode NFSv4 CB basic data types 86 * 87 * Basic NFSv4 callback data types are defined in section 15 of RFC 88 * 3530: "Network File System (NFS) version 4 Protocol" and section 89 * 20 of RFC 5661: "Network File System (NFS) Version 4 Minor Version 90 * 1 Protocol" 91 */ 92 93 /* 94 * nfs_cb_opnum4 95 * 96 * enum nfs_cb_opnum4 { 97 * OP_CB_GETATTR = 3, 98 * ... 99 * }; 100 */ 101 enum nfs_cb_opnum4 { 102 OP_CB_GETATTR = 3, 103 OP_CB_RECALL = 4, 104 OP_CB_LAYOUTRECALL = 5, 105 OP_CB_NOTIFY = 6, 106 OP_CB_PUSH_DELEG = 7, 107 OP_CB_RECALL_ANY = 8, 108 OP_CB_RECALLABLE_OBJ_AVAIL = 9, 109 OP_CB_RECALL_SLOT = 10, 110 OP_CB_SEQUENCE = 11, 111 OP_CB_WANTS_CANCELLED = 12, 112 OP_CB_NOTIFY_LOCK = 13, 113 OP_CB_NOTIFY_DEVICEID = 14, 114 OP_CB_ILLEGAL = 10044 115 }; 116 117 static void encode_nfs_cb_opnum4(struct xdr_stream *xdr, enum nfs_cb_opnum4 op) 118 { 119 __be32 *p; 120 121 p = xdr_reserve_space(xdr, 4); 122 *p = cpu_to_be32(op); 123 } 124 125 /* 126 * nfs_fh4 127 * 128 * typedef opaque nfs_fh4<NFS4_FHSIZE>; 129 */ 130 static void encode_nfs_fh4(struct xdr_stream *xdr, const struct knfsd_fh *fh) 131 { 132 u32 length = fh->fh_size; 133 __be32 *p; 134 135 BUG_ON(length > NFS4_FHSIZE); 136 p = xdr_reserve_space(xdr, 4 + length); 137 xdr_encode_opaque(p, &fh->fh_base, length); 138 } 139 140 /* 141 * stateid4 142 * 143 * struct stateid4 { 144 * uint32_t seqid; 145 * opaque other[12]; 146 * }; 147 */ 148 static void encode_stateid4(struct xdr_stream *xdr, const stateid_t *sid) 149 { 150 __be32 *p; 151 152 p = xdr_reserve_space(xdr, NFS4_STATEID_SIZE); 153 *p++ = cpu_to_be32(sid->si_generation); 154 xdr_encode_opaque_fixed(p, &sid->si_opaque, NFS4_STATEID_OTHER_SIZE); 155 } 156 157 /* 158 * sessionid4 159 * 160 * typedef opaque sessionid4[NFS4_SESSIONID_SIZE]; 161 */ 162 static void encode_sessionid4(struct xdr_stream *xdr, 163 const struct nfsd4_session *session) 164 { 165 __be32 *p; 166 167 p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN); 168 xdr_encode_opaque_fixed(p, session->se_sessionid.data, 169 NFS4_MAX_SESSIONID_LEN); 170 } 171 172 /* 173 * nfsstat4 174 */ 175 static const struct { 176 int stat; 177 int errno; 178 } nfs_cb_errtbl[] = { 179 { NFS4_OK, 0 }, 180 { NFS4ERR_PERM, -EPERM }, 181 { NFS4ERR_NOENT, -ENOENT }, 182 { NFS4ERR_IO, -EIO }, 183 { NFS4ERR_NXIO, -ENXIO }, 184 { NFS4ERR_ACCESS, -EACCES }, 185 { NFS4ERR_EXIST, -EEXIST }, 186 { NFS4ERR_XDEV, -EXDEV }, 187 { NFS4ERR_NOTDIR, -ENOTDIR }, 188 { NFS4ERR_ISDIR, -EISDIR }, 189 { NFS4ERR_INVAL, -EINVAL }, 190 { NFS4ERR_FBIG, -EFBIG }, 191 { NFS4ERR_NOSPC, -ENOSPC }, 192 { NFS4ERR_ROFS, -EROFS }, 193 { NFS4ERR_MLINK, -EMLINK }, 194 { NFS4ERR_NAMETOOLONG, -ENAMETOOLONG }, 195 { NFS4ERR_NOTEMPTY, -ENOTEMPTY }, 196 { NFS4ERR_DQUOT, -EDQUOT }, 197 { NFS4ERR_STALE, -ESTALE }, 198 { NFS4ERR_BADHANDLE, -EBADHANDLE }, 199 { NFS4ERR_BAD_COOKIE, -EBADCOOKIE }, 200 { NFS4ERR_NOTSUPP, -ENOTSUPP }, 201 { NFS4ERR_TOOSMALL, -ETOOSMALL }, 202 { NFS4ERR_SERVERFAULT, -ESERVERFAULT }, 203 { NFS4ERR_BADTYPE, -EBADTYPE }, 204 { NFS4ERR_LOCKED, -EAGAIN }, 205 { NFS4ERR_RESOURCE, -EREMOTEIO }, 206 { NFS4ERR_SYMLINK, -ELOOP }, 207 { NFS4ERR_OP_ILLEGAL, -EOPNOTSUPP }, 208 { NFS4ERR_DEADLOCK, -EDEADLK }, 209 { -1, -EIO } 210 }; 211 212 /* 213 * If we cannot translate the error, the recovery routines should 214 * handle it. 215 * 216 * Note: remaining NFSv4 error codes have values > 10000, so should 217 * not conflict with native Linux error codes. 218 */ 219 static int nfs_cb_stat_to_errno(int status) 220 { 221 int i; 222 223 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 224 if (nfs_cb_errtbl[i].stat == status) 225 return nfs_cb_errtbl[i].errno; 226 } 227 228 dprintk("NFSD: Unrecognized NFS CB status value: %u\n", status); 229 return -status; 230 } 231 232 static int decode_cb_op_status(struct xdr_stream *xdr, enum nfs_opnum4 expected, 233 enum nfsstat4 *status) 234 { 235 __be32 *p; 236 u32 op; 237 238 p = xdr_inline_decode(xdr, 4 + 4); 239 if (unlikely(p == NULL)) 240 goto out_overflow; 241 op = be32_to_cpup(p++); 242 if (unlikely(op != expected)) 243 goto out_unexpected; 244 *status = be32_to_cpup(p); 245 return 0; 246 out_overflow: 247 print_overflow_msg(__func__, xdr); 248 return -EIO; 249 out_unexpected: 250 dprintk("NFSD: Callback server returned operation %d but " 251 "we issued a request for %d\n", op, expected); 252 return -EIO; 253 } 254 255 /* 256 * CB_COMPOUND4args 257 * 258 * struct CB_COMPOUND4args { 259 * utf8str_cs tag; 260 * uint32_t minorversion; 261 * uint32_t callback_ident; 262 * nfs_cb_argop4 argarray<>; 263 * }; 264 */ 265 static void encode_cb_compound4args(struct xdr_stream *xdr, 266 struct nfs4_cb_compound_hdr *hdr) 267 { 268 __be32 * p; 269 270 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 271 p = xdr_encode_empty_array(p); /* empty tag */ 272 *p++ = cpu_to_be32(hdr->minorversion); 273 *p++ = cpu_to_be32(hdr->ident); 274 275 hdr->nops_p = p; 276 *p = cpu_to_be32(hdr->nops); /* argarray element count */ 277 } 278 279 /* 280 * Update argarray element count 281 */ 282 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr) 283 { 284 BUG_ON(hdr->nops > NFS4_MAX_BACK_CHANNEL_OPS); 285 *hdr->nops_p = cpu_to_be32(hdr->nops); 286 } 287 288 /* 289 * CB_COMPOUND4res 290 * 291 * struct CB_COMPOUND4res { 292 * nfsstat4 status; 293 * utf8str_cs tag; 294 * nfs_cb_resop4 resarray<>; 295 * }; 296 */ 297 static int decode_cb_compound4res(struct xdr_stream *xdr, 298 struct nfs4_cb_compound_hdr *hdr) 299 { 300 u32 length; 301 __be32 *p; 302 303 p = xdr_inline_decode(xdr, 4 + 4); 304 if (unlikely(p == NULL)) 305 goto out_overflow; 306 hdr->status = be32_to_cpup(p++); 307 /* Ignore the tag */ 308 length = be32_to_cpup(p++); 309 p = xdr_inline_decode(xdr, length + 4); 310 if (unlikely(p == NULL)) 311 goto out_overflow; 312 hdr->nops = be32_to_cpup(p); 313 return 0; 314 out_overflow: 315 print_overflow_msg(__func__, xdr); 316 return -EIO; 317 } 318 319 /* 320 * CB_RECALL4args 321 * 322 * struct CB_RECALL4args { 323 * stateid4 stateid; 324 * bool truncate; 325 * nfs_fh4 fh; 326 * }; 327 */ 328 static void encode_cb_recall4args(struct xdr_stream *xdr, 329 const struct nfs4_delegation *dp, 330 struct nfs4_cb_compound_hdr *hdr) 331 { 332 __be32 *p; 333 334 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL); 335 encode_stateid4(xdr, &dp->dl_stid.sc_stateid); 336 337 p = xdr_reserve_space(xdr, 4); 338 *p++ = xdr_zero; /* truncate */ 339 340 encode_nfs_fh4(xdr, &dp->dl_stid.sc_file->fi_fhandle); 341 342 hdr->nops++; 343 } 344 345 /* 346 * CB_SEQUENCE4args 347 * 348 * struct CB_SEQUENCE4args { 349 * sessionid4 csa_sessionid; 350 * sequenceid4 csa_sequenceid; 351 * slotid4 csa_slotid; 352 * slotid4 csa_highest_slotid; 353 * bool csa_cachethis; 354 * referring_call_list4 csa_referring_call_lists<>; 355 * }; 356 */ 357 static void encode_cb_sequence4args(struct xdr_stream *xdr, 358 const struct nfsd4_callback *cb, 359 struct nfs4_cb_compound_hdr *hdr) 360 { 361 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 362 __be32 *p; 363 364 if (hdr->minorversion == 0) 365 return; 366 367 encode_nfs_cb_opnum4(xdr, OP_CB_SEQUENCE); 368 encode_sessionid4(xdr, session); 369 370 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4 + 4); 371 *p++ = cpu_to_be32(session->se_cb_seq_nr); /* csa_sequenceid */ 372 *p++ = xdr_zero; /* csa_slotid */ 373 *p++ = xdr_zero; /* csa_highest_slotid */ 374 *p++ = xdr_zero; /* csa_cachethis */ 375 xdr_encode_empty_array(p); /* csa_referring_call_lists */ 376 377 hdr->nops++; 378 } 379 380 /* 381 * CB_SEQUENCE4resok 382 * 383 * struct CB_SEQUENCE4resok { 384 * sessionid4 csr_sessionid; 385 * sequenceid4 csr_sequenceid; 386 * slotid4 csr_slotid; 387 * slotid4 csr_highest_slotid; 388 * slotid4 csr_target_highest_slotid; 389 * }; 390 * 391 * union CB_SEQUENCE4res switch (nfsstat4 csr_status) { 392 * case NFS4_OK: 393 * CB_SEQUENCE4resok csr_resok4; 394 * default: 395 * void; 396 * }; 397 * 398 * Our current back channel implmentation supports a single backchannel 399 * with a single slot. 400 */ 401 static int decode_cb_sequence4resok(struct xdr_stream *xdr, 402 struct nfsd4_callback *cb) 403 { 404 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 405 struct nfs4_sessionid id; 406 int status; 407 __be32 *p; 408 u32 dummy; 409 410 status = -ESERVERFAULT; 411 412 /* 413 * If the server returns different values for sessionID, slotID or 414 * sequence number, the server is looney tunes. 415 */ 416 p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4); 417 if (unlikely(p == NULL)) 418 goto out_overflow; 419 memcpy(id.data, p, NFS4_MAX_SESSIONID_LEN); 420 if (memcmp(id.data, session->se_sessionid.data, 421 NFS4_MAX_SESSIONID_LEN) != 0) { 422 dprintk("NFS: %s Invalid session id\n", __func__); 423 goto out; 424 } 425 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN); 426 427 dummy = be32_to_cpup(p++); 428 if (dummy != session->se_cb_seq_nr) { 429 dprintk("NFS: %s Invalid sequence number\n", __func__); 430 goto out; 431 } 432 433 dummy = be32_to_cpup(p++); 434 if (dummy != 0) { 435 dprintk("NFS: %s Invalid slotid\n", __func__); 436 goto out; 437 } 438 439 /* 440 * FIXME: process highest slotid and target highest slotid 441 */ 442 status = 0; 443 out: 444 if (status) 445 nfsd4_mark_cb_fault(cb->cb_clp, status); 446 return status; 447 out_overflow: 448 print_overflow_msg(__func__, xdr); 449 return -EIO; 450 } 451 452 static int decode_cb_sequence4res(struct xdr_stream *xdr, 453 struct nfsd4_callback *cb) 454 { 455 enum nfsstat4 nfserr; 456 int status; 457 458 if (cb->cb_minorversion == 0) 459 return 0; 460 461 status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &nfserr); 462 if (unlikely(status)) 463 goto out; 464 if (unlikely(nfserr != NFS4_OK)) 465 goto out_default; 466 status = decode_cb_sequence4resok(xdr, cb); 467 out: 468 return status; 469 out_default: 470 return nfs_cb_stat_to_errno(nfserr); 471 } 472 473 /* 474 * NFSv4.0 and NFSv4.1 XDR encode functions 475 * 476 * NFSv4.0 callback argument types are defined in section 15 of RFC 477 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 478 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 479 * Protocol". 480 */ 481 482 /* 483 * NB: Without this zero space reservation, callbacks over krb5p fail 484 */ 485 static void nfs4_xdr_enc_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 486 void *__unused) 487 { 488 xdr_reserve_space(xdr, 0); 489 } 490 491 /* 492 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 493 */ 494 static void nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, struct xdr_stream *xdr, 495 const struct nfsd4_callback *cb) 496 { 497 const struct nfs4_delegation *args = cb->cb_op; 498 struct nfs4_cb_compound_hdr hdr = { 499 .ident = cb->cb_clp->cl_cb_ident, 500 .minorversion = cb->cb_minorversion, 501 }; 502 503 encode_cb_compound4args(xdr, &hdr); 504 encode_cb_sequence4args(xdr, cb, &hdr); 505 encode_cb_recall4args(xdr, args, &hdr); 506 encode_cb_nops(&hdr); 507 } 508 509 510 /* 511 * NFSv4.0 and NFSv4.1 XDR decode functions 512 * 513 * NFSv4.0 callback result types are defined in section 15 of RFC 514 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 515 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 516 * Protocol". 517 */ 518 519 static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 520 void *__unused) 521 { 522 return 0; 523 } 524 525 /* 526 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 527 */ 528 static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, 529 struct xdr_stream *xdr, 530 struct nfsd4_callback *cb) 531 { 532 struct nfs4_cb_compound_hdr hdr; 533 enum nfsstat4 nfserr; 534 int status; 535 536 status = decode_cb_compound4res(xdr, &hdr); 537 if (unlikely(status)) 538 goto out; 539 540 if (cb != NULL) { 541 status = decode_cb_sequence4res(xdr, cb); 542 if (unlikely(status)) 543 goto out; 544 } 545 546 status = decode_cb_op_status(xdr, OP_CB_RECALL, &nfserr); 547 if (unlikely(status)) 548 goto out; 549 if (unlikely(nfserr != NFS4_OK)) 550 status = nfs_cb_stat_to_errno(nfserr); 551 out: 552 return status; 553 } 554 555 /* 556 * RPC procedure tables 557 */ 558 #define PROC(proc, call, argtype, restype) \ 559 [NFSPROC4_CLNT_##proc] = { \ 560 .p_proc = NFSPROC4_CB_##call, \ 561 .p_encode = (kxdreproc_t)nfs4_xdr_enc_##argtype, \ 562 .p_decode = (kxdrdproc_t)nfs4_xdr_dec_##restype, \ 563 .p_arglen = NFS4_enc_##argtype##_sz, \ 564 .p_replen = NFS4_dec_##restype##_sz, \ 565 .p_statidx = NFSPROC4_CB_##call, \ 566 .p_name = #proc, \ 567 } 568 569 static struct rpc_procinfo nfs4_cb_procedures[] = { 570 PROC(CB_NULL, NULL, cb_null, cb_null), 571 PROC(CB_RECALL, COMPOUND, cb_recall, cb_recall), 572 }; 573 574 static struct rpc_version nfs_cb_version4 = { 575 /* 576 * Note on the callback rpc program version number: despite language in rfc 577 * 5661 section 18.36.3 requiring servers to use 4 in this field, the 578 * official xdr descriptions for both 4.0 and 4.1 specify version 1, and 579 * in practice that appears to be what implementations use. The section 580 * 18.36.3 language is expected to be fixed in an erratum. 581 */ 582 .number = 1, 583 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 584 .procs = nfs4_cb_procedures 585 }; 586 587 static const struct rpc_version *nfs_cb_version[] = { 588 &nfs_cb_version4, 589 }; 590 591 static const struct rpc_program cb_program; 592 593 static struct rpc_stat cb_stats = { 594 .program = &cb_program 595 }; 596 597 #define NFS4_CALLBACK 0x40000000 598 static const struct rpc_program cb_program = { 599 .name = "nfs4_cb", 600 .number = NFS4_CALLBACK, 601 .nrvers = ARRAY_SIZE(nfs_cb_version), 602 .version = nfs_cb_version, 603 .stats = &cb_stats, 604 .pipe_dir_name = "nfsd4_cb", 605 }; 606 607 static int max_cb_time(struct net *net) 608 { 609 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 610 return max(nn->nfsd4_lease/10, (time_t)1) * HZ; 611 } 612 613 static struct rpc_cred *callback_cred; 614 615 int set_callback_cred(void) 616 { 617 if (callback_cred) 618 return 0; 619 callback_cred = rpc_lookup_machine_cred("nfs"); 620 if (!callback_cred) 621 return -ENOMEM; 622 return 0; 623 } 624 625 static struct rpc_cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc_clnt *client, struct nfsd4_session *ses) 626 { 627 if (clp->cl_minorversion == 0) { 628 return get_rpccred(callback_cred); 629 } else { 630 struct rpc_auth *auth = client->cl_auth; 631 struct auth_cred acred = {}; 632 633 acred.uid = ses->se_cb_sec.uid; 634 acred.gid = ses->se_cb_sec.gid; 635 return auth->au_ops->lookup_cred(client->cl_auth, &acred, 0); 636 } 637 } 638 639 static struct rpc_clnt *create_backchannel_client(struct rpc_create_args *args) 640 { 641 struct rpc_xprt *xprt; 642 643 if (args->protocol != XPRT_TRANSPORT_BC_TCP) 644 return rpc_create(args); 645 646 xprt = args->bc_xprt->xpt_bc_xprt; 647 if (xprt) { 648 xprt_get(xprt); 649 return rpc_create_xprt(args, xprt); 650 } 651 652 return rpc_create(args); 653 } 654 655 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses) 656 { 657 int maxtime = max_cb_time(clp->net); 658 struct rpc_timeout timeparms = { 659 .to_initval = maxtime, 660 .to_retries = 0, 661 .to_maxval = maxtime, 662 }; 663 struct rpc_create_args args = { 664 .net = clp->net, 665 .address = (struct sockaddr *) &conn->cb_addr, 666 .addrsize = conn->cb_addrlen, 667 .saddress = (struct sockaddr *) &conn->cb_saddr, 668 .timeout = &timeparms, 669 .program = &cb_program, 670 .version = 0, 671 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), 672 }; 673 struct rpc_clnt *client; 674 struct rpc_cred *cred; 675 676 if (clp->cl_minorversion == 0) { 677 if (!clp->cl_cred.cr_principal && 678 (clp->cl_cred.cr_flavor >= RPC_AUTH_GSS_KRB5)) 679 return -EINVAL; 680 args.client_name = clp->cl_cred.cr_principal; 681 args.prognumber = conn->cb_prog; 682 args.protocol = XPRT_TRANSPORT_TCP; 683 args.authflavor = clp->cl_cred.cr_flavor; 684 clp->cl_cb_ident = conn->cb_ident; 685 } else { 686 if (!conn->cb_xprt) 687 return -EINVAL; 688 clp->cl_cb_conn.cb_xprt = conn->cb_xprt; 689 clp->cl_cb_session = ses; 690 args.bc_xprt = conn->cb_xprt; 691 args.prognumber = clp->cl_cb_session->se_cb_prog; 692 args.protocol = conn->cb_xprt->xpt_class->xcl_ident | 693 XPRT_TRANSPORT_BC; 694 args.authflavor = ses->se_cb_sec.flavor; 695 } 696 /* Create RPC client */ 697 client = create_backchannel_client(&args); 698 if (IS_ERR(client)) { 699 dprintk("NFSD: couldn't create callback client: %ld\n", 700 PTR_ERR(client)); 701 return PTR_ERR(client); 702 } 703 cred = get_backchannel_cred(clp, client, ses); 704 if (IS_ERR(cred)) { 705 rpc_shutdown_client(client); 706 return PTR_ERR(cred); 707 } 708 clp->cl_cb_client = client; 709 clp->cl_cb_cred = cred; 710 return 0; 711 } 712 713 static void warn_no_callback_path(struct nfs4_client *clp, int reason) 714 { 715 dprintk("NFSD: warning: no callback path to client %.*s: error %d\n", 716 (int)clp->cl_name.len, clp->cl_name.data, reason); 717 } 718 719 static void nfsd4_mark_cb_down(struct nfs4_client *clp, int reason) 720 { 721 clp->cl_cb_state = NFSD4_CB_DOWN; 722 warn_no_callback_path(clp, reason); 723 } 724 725 static void nfsd4_mark_cb_fault(struct nfs4_client *clp, int reason) 726 { 727 clp->cl_cb_state = NFSD4_CB_FAULT; 728 warn_no_callback_path(clp, reason); 729 } 730 731 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata) 732 { 733 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 734 735 if (task->tk_status) 736 nfsd4_mark_cb_down(clp, task->tk_status); 737 else 738 clp->cl_cb_state = NFSD4_CB_UP; 739 } 740 741 static const struct rpc_call_ops nfsd4_cb_probe_ops = { 742 /* XXX: release method to ensure we set the cb channel down if 743 * necessary on early failure? */ 744 .rpc_call_done = nfsd4_cb_probe_done, 745 }; 746 747 static struct workqueue_struct *callback_wq; 748 749 static void run_nfsd4_cb(struct nfsd4_callback *cb) 750 { 751 queue_work(callback_wq, &cb->cb_work); 752 } 753 754 static void do_probe_callback(struct nfs4_client *clp) 755 { 756 struct nfsd4_callback *cb = &clp->cl_cb_null; 757 758 cb->cb_op = NULL; 759 cb->cb_clp = clp; 760 761 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL]; 762 cb->cb_msg.rpc_argp = NULL; 763 cb->cb_msg.rpc_resp = NULL; 764 765 cb->cb_ops = &nfsd4_cb_probe_ops; 766 767 run_nfsd4_cb(cb); 768 } 769 770 /* 771 * Poke the callback thread to process any updates to the callback 772 * parameters, and send a null probe. 773 */ 774 void nfsd4_probe_callback(struct nfs4_client *clp) 775 { 776 clp->cl_cb_state = NFSD4_CB_UNKNOWN; 777 set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 778 do_probe_callback(clp); 779 } 780 781 void nfsd4_probe_callback_sync(struct nfs4_client *clp) 782 { 783 nfsd4_probe_callback(clp); 784 flush_workqueue(callback_wq); 785 } 786 787 void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn) 788 { 789 clp->cl_cb_state = NFSD4_CB_UNKNOWN; 790 spin_lock(&clp->cl_lock); 791 memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn)); 792 spin_unlock(&clp->cl_lock); 793 } 794 795 /* 796 * There's currently a single callback channel slot. 797 * If the slot is available, then mark it busy. Otherwise, set the 798 * thread for sleeping on the callback RPC wait queue. 799 */ 800 static bool nfsd41_cb_get_slot(struct nfs4_client *clp, struct rpc_task *task) 801 { 802 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 803 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL); 804 dprintk("%s slot is busy\n", __func__); 805 return false; 806 } 807 return true; 808 } 809 810 /* 811 * TODO: cb_sequence should support referring call lists, cachethis, multiple 812 * slots, and mark callback channel down on communication errors. 813 */ 814 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata) 815 { 816 struct nfsd4_callback *cb = calldata; 817 struct nfs4_client *clp = cb->cb_clp; 818 u32 minorversion = clp->cl_minorversion; 819 820 cb->cb_minorversion = minorversion; 821 if (minorversion) { 822 if (!nfsd41_cb_get_slot(clp, task)) 823 return; 824 } 825 spin_lock(&clp->cl_lock); 826 if (list_empty(&cb->cb_per_client)) { 827 /* This is the first call, not a restart */ 828 cb->cb_done = false; 829 list_add(&cb->cb_per_client, &clp->cl_callbacks); 830 } 831 spin_unlock(&clp->cl_lock); 832 rpc_call_start(task); 833 } 834 835 static void nfsd4_cb_done(struct rpc_task *task, void *calldata) 836 { 837 struct nfsd4_callback *cb = calldata; 838 struct nfs4_client *clp = cb->cb_clp; 839 840 dprintk("%s: minorversion=%d\n", __func__, 841 clp->cl_minorversion); 842 843 if (clp->cl_minorversion) { 844 /* No need for lock, access serialized in nfsd4_cb_prepare */ 845 ++clp->cl_cb_session->se_cb_seq_nr; 846 clear_bit(0, &clp->cl_cb_slot_busy); 847 rpc_wake_up_next(&clp->cl_cb_waitq); 848 dprintk("%s: freed slot, new seqid=%d\n", __func__, 849 clp->cl_cb_session->se_cb_seq_nr); 850 851 /* We're done looking into the sequence information */ 852 task->tk_msg.rpc_resp = NULL; 853 } 854 } 855 856 857 static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata) 858 { 859 struct nfsd4_callback *cb = calldata; 860 struct nfs4_delegation *dp = container_of(cb, struct nfs4_delegation, dl_recall); 861 struct nfs4_client *clp = cb->cb_clp; 862 struct rpc_clnt *current_rpc_client = clp->cl_cb_client; 863 864 nfsd4_cb_done(task, calldata); 865 866 if (current_rpc_client != task->tk_client) { 867 /* We're shutting down or changing cl_cb_client; leave 868 * it to nfsd4_process_cb_update to restart the call if 869 * necessary. */ 870 return; 871 } 872 873 if (cb->cb_done) 874 return; 875 switch (task->tk_status) { 876 case 0: 877 cb->cb_done = true; 878 return; 879 case -EBADHANDLE: 880 case -NFS4ERR_BAD_STATEID: 881 /* Race: client probably got cb_recall 882 * before open reply granting delegation */ 883 break; 884 default: 885 /* Network partition? */ 886 nfsd4_mark_cb_down(clp, task->tk_status); 887 } 888 if (dp->dl_retries--) { 889 rpc_delay(task, 2*HZ); 890 task->tk_status = 0; 891 rpc_restart_call_prepare(task); 892 return; 893 } 894 nfsd4_mark_cb_down(clp, task->tk_status); 895 cb->cb_done = true; 896 } 897 898 static void nfsd4_cb_recall_release(void *calldata) 899 { 900 struct nfsd4_callback *cb = calldata; 901 struct nfs4_client *clp = cb->cb_clp; 902 struct nfs4_delegation *dp = container_of(cb, struct nfs4_delegation, dl_recall); 903 904 if (cb->cb_done) { 905 spin_lock(&clp->cl_lock); 906 list_del(&cb->cb_per_client); 907 spin_unlock(&clp->cl_lock); 908 nfs4_put_stid(&dp->dl_stid); 909 } 910 } 911 912 static const struct rpc_call_ops nfsd4_cb_recall_ops = { 913 .rpc_call_prepare = nfsd4_cb_prepare, 914 .rpc_call_done = nfsd4_cb_recall_done, 915 .rpc_release = nfsd4_cb_recall_release, 916 }; 917 918 int nfsd4_create_callback_queue(void) 919 { 920 callback_wq = create_singlethread_workqueue("nfsd4_callbacks"); 921 if (!callback_wq) 922 return -ENOMEM; 923 return 0; 924 } 925 926 void nfsd4_destroy_callback_queue(void) 927 { 928 destroy_workqueue(callback_wq); 929 } 930 931 /* must be called under the state lock */ 932 void nfsd4_shutdown_callback(struct nfs4_client *clp) 933 { 934 set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); 935 /* 936 * Note this won't actually result in a null callback; 937 * instead, nfsd4_run_cb_null() will detect the killed 938 * client, destroy the rpc client, and stop: 939 */ 940 do_probe_callback(clp); 941 flush_workqueue(callback_wq); 942 } 943 944 static void nfsd4_release_cb(struct nfsd4_callback *cb) 945 { 946 if (cb->cb_ops->rpc_release) 947 cb->cb_ops->rpc_release(cb); 948 } 949 950 /* requires cl_lock: */ 951 static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp) 952 { 953 struct nfsd4_session *s; 954 struct nfsd4_conn *c; 955 956 list_for_each_entry(s, &clp->cl_sessions, se_perclnt) { 957 list_for_each_entry(c, &s->se_conns, cn_persession) { 958 if (c->cn_flags & NFS4_CDFC4_BACK) 959 return c; 960 } 961 } 962 return NULL; 963 } 964 965 static void nfsd4_process_cb_update(struct nfsd4_callback *cb) 966 { 967 struct nfs4_cb_conn conn; 968 struct nfs4_client *clp = cb->cb_clp; 969 struct nfsd4_session *ses = NULL; 970 struct nfsd4_conn *c; 971 int err; 972 973 /* 974 * This is either an update, or the client dying; in either case, 975 * kill the old client: 976 */ 977 if (clp->cl_cb_client) { 978 rpc_shutdown_client(clp->cl_cb_client); 979 clp->cl_cb_client = NULL; 980 put_rpccred(clp->cl_cb_cred); 981 clp->cl_cb_cred = NULL; 982 } 983 if (clp->cl_cb_conn.cb_xprt) { 984 svc_xprt_put(clp->cl_cb_conn.cb_xprt); 985 clp->cl_cb_conn.cb_xprt = NULL; 986 } 987 if (test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) 988 return; 989 spin_lock(&clp->cl_lock); 990 /* 991 * Only serialized callback code is allowed to clear these 992 * flags; main nfsd code can only set them: 993 */ 994 BUG_ON(!(clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK)); 995 clear_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 996 memcpy(&conn, &cb->cb_clp->cl_cb_conn, sizeof(struct nfs4_cb_conn)); 997 c = __nfsd4_find_backchannel(clp); 998 if (c) { 999 svc_xprt_get(c->cn_xprt); 1000 conn.cb_xprt = c->cn_xprt; 1001 ses = c->cn_session; 1002 } 1003 spin_unlock(&clp->cl_lock); 1004 1005 err = setup_callback_client(clp, &conn, ses); 1006 if (err) { 1007 nfsd4_mark_cb_down(clp, err); 1008 return; 1009 } 1010 /* Yay, the callback channel's back! Restart any callbacks: */ 1011 list_for_each_entry(cb, &clp->cl_callbacks, cb_per_client) 1012 run_nfsd4_cb(cb); 1013 } 1014 1015 static void 1016 nfsd4_run_callback_rpc(struct nfsd4_callback *cb) 1017 { 1018 struct nfs4_client *clp = cb->cb_clp; 1019 struct rpc_clnt *clnt; 1020 1021 if (clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK) 1022 nfsd4_process_cb_update(cb); 1023 1024 clnt = clp->cl_cb_client; 1025 if (!clnt) { 1026 /* Callback channel broken, or client killed; give up: */ 1027 nfsd4_release_cb(cb); 1028 return; 1029 } 1030 cb->cb_msg.rpc_cred = clp->cl_cb_cred; 1031 rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN, 1032 cb->cb_ops, cb); 1033 } 1034 1035 void 1036 nfsd4_run_cb_null(struct work_struct *w) 1037 { 1038 struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, 1039 cb_work); 1040 nfsd4_run_callback_rpc(cb); 1041 } 1042 1043 void 1044 nfsd4_run_cb_recall(struct work_struct *w) 1045 { 1046 struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback, 1047 cb_work); 1048 1049 nfsd4_prepare_cb_recall(cb->cb_op); 1050 nfsd4_run_callback_rpc(cb); 1051 } 1052 1053 void nfsd4_cb_recall(struct nfs4_delegation *dp) 1054 { 1055 struct nfsd4_callback *cb = &dp->dl_recall; 1056 struct nfs4_client *clp = dp->dl_stid.sc_client; 1057 1058 dp->dl_retries = 1; 1059 cb->cb_op = dp; 1060 cb->cb_clp = clp; 1061 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL]; 1062 cb->cb_msg.rpc_argp = cb; 1063 cb->cb_msg.rpc_resp = cb; 1064 1065 cb->cb_ops = &nfsd4_cb_recall_ops; 1066 1067 INIT_LIST_HEAD(&cb->cb_per_client); 1068 cb->cb_done = true; 1069 1070 run_nfsd4_cb(&dp->dl_recall); 1071 } 1072