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 struct nfs4_cb_compound_hdr { 53 /* args */ 54 u32 ident; /* minorversion 0 only */ 55 u32 nops; 56 __be32 *nops_p; 57 u32 minorversion; 58 /* res */ 59 int status; 60 }; 61 62 /* 63 * Handle decode buffer overflows out-of-line. 64 */ 65 static void print_overflow_msg(const char *func, const struct xdr_stream *xdr) 66 { 67 dprintk("NFS: %s prematurely hit the end of our receive buffer. " 68 "Remaining buffer length is %tu words.\n", 69 func, xdr->end - xdr->p); 70 } 71 72 static __be32 *xdr_encode_empty_array(__be32 *p) 73 { 74 *p++ = xdr_zero; 75 return p; 76 } 77 78 /* 79 * Encode/decode NFSv4 CB basic data types 80 * 81 * Basic NFSv4 callback data types are defined in section 15 of RFC 82 * 3530: "Network File System (NFS) version 4 Protocol" and section 83 * 20 of RFC 5661: "Network File System (NFS) Version 4 Minor Version 84 * 1 Protocol" 85 */ 86 87 /* 88 * nfs_cb_opnum4 89 * 90 * enum nfs_cb_opnum4 { 91 * OP_CB_GETATTR = 3, 92 * ... 93 * }; 94 */ 95 enum nfs_cb_opnum4 { 96 OP_CB_GETATTR = 3, 97 OP_CB_RECALL = 4, 98 OP_CB_LAYOUTRECALL = 5, 99 OP_CB_NOTIFY = 6, 100 OP_CB_PUSH_DELEG = 7, 101 OP_CB_RECALL_ANY = 8, 102 OP_CB_RECALLABLE_OBJ_AVAIL = 9, 103 OP_CB_RECALL_SLOT = 10, 104 OP_CB_SEQUENCE = 11, 105 OP_CB_WANTS_CANCELLED = 12, 106 OP_CB_NOTIFY_LOCK = 13, 107 OP_CB_NOTIFY_DEVICEID = 14, 108 OP_CB_ILLEGAL = 10044 109 }; 110 111 static void encode_nfs_cb_opnum4(struct xdr_stream *xdr, enum nfs_cb_opnum4 op) 112 { 113 __be32 *p; 114 115 p = xdr_reserve_space(xdr, 4); 116 *p = cpu_to_be32(op); 117 } 118 119 /* 120 * nfs_fh4 121 * 122 * typedef opaque nfs_fh4<NFS4_FHSIZE>; 123 */ 124 static void encode_nfs_fh4(struct xdr_stream *xdr, const struct knfsd_fh *fh) 125 { 126 u32 length = fh->fh_size; 127 __be32 *p; 128 129 BUG_ON(length > NFS4_FHSIZE); 130 p = xdr_reserve_space(xdr, 4 + length); 131 xdr_encode_opaque(p, &fh->fh_base, length); 132 } 133 134 /* 135 * stateid4 136 * 137 * struct stateid4 { 138 * uint32_t seqid; 139 * opaque other[12]; 140 * }; 141 */ 142 static void encode_stateid4(struct xdr_stream *xdr, const stateid_t *sid) 143 { 144 __be32 *p; 145 146 p = xdr_reserve_space(xdr, NFS4_STATEID_SIZE); 147 *p++ = cpu_to_be32(sid->si_generation); 148 xdr_encode_opaque_fixed(p, &sid->si_opaque, NFS4_STATEID_OTHER_SIZE); 149 } 150 151 /* 152 * sessionid4 153 * 154 * typedef opaque sessionid4[NFS4_SESSIONID_SIZE]; 155 */ 156 static void encode_sessionid4(struct xdr_stream *xdr, 157 const struct nfsd4_session *session) 158 { 159 __be32 *p; 160 161 p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN); 162 xdr_encode_opaque_fixed(p, session->se_sessionid.data, 163 NFS4_MAX_SESSIONID_LEN); 164 } 165 166 /* 167 * nfsstat4 168 */ 169 static const struct { 170 int stat; 171 int errno; 172 } nfs_cb_errtbl[] = { 173 { NFS4_OK, 0 }, 174 { NFS4ERR_PERM, -EPERM }, 175 { NFS4ERR_NOENT, -ENOENT }, 176 { NFS4ERR_IO, -EIO }, 177 { NFS4ERR_NXIO, -ENXIO }, 178 { NFS4ERR_ACCESS, -EACCES }, 179 { NFS4ERR_EXIST, -EEXIST }, 180 { NFS4ERR_XDEV, -EXDEV }, 181 { NFS4ERR_NOTDIR, -ENOTDIR }, 182 { NFS4ERR_ISDIR, -EISDIR }, 183 { NFS4ERR_INVAL, -EINVAL }, 184 { NFS4ERR_FBIG, -EFBIG }, 185 { NFS4ERR_NOSPC, -ENOSPC }, 186 { NFS4ERR_ROFS, -EROFS }, 187 { NFS4ERR_MLINK, -EMLINK }, 188 { NFS4ERR_NAMETOOLONG, -ENAMETOOLONG }, 189 { NFS4ERR_NOTEMPTY, -ENOTEMPTY }, 190 { NFS4ERR_DQUOT, -EDQUOT }, 191 { NFS4ERR_STALE, -ESTALE }, 192 { NFS4ERR_BADHANDLE, -EBADHANDLE }, 193 { NFS4ERR_BAD_COOKIE, -EBADCOOKIE }, 194 { NFS4ERR_NOTSUPP, -ENOTSUPP }, 195 { NFS4ERR_TOOSMALL, -ETOOSMALL }, 196 { NFS4ERR_SERVERFAULT, -ESERVERFAULT }, 197 { NFS4ERR_BADTYPE, -EBADTYPE }, 198 { NFS4ERR_LOCKED, -EAGAIN }, 199 { NFS4ERR_RESOURCE, -EREMOTEIO }, 200 { NFS4ERR_SYMLINK, -ELOOP }, 201 { NFS4ERR_OP_ILLEGAL, -EOPNOTSUPP }, 202 { NFS4ERR_DEADLOCK, -EDEADLK }, 203 { -1, -EIO } 204 }; 205 206 /* 207 * If we cannot translate the error, the recovery routines should 208 * handle it. 209 * 210 * Note: remaining NFSv4 error codes have values > 10000, so should 211 * not conflict with native Linux error codes. 212 */ 213 static int nfs_cb_stat_to_errno(int status) 214 { 215 int i; 216 217 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 218 if (nfs_cb_errtbl[i].stat == status) 219 return nfs_cb_errtbl[i].errno; 220 } 221 222 dprintk("NFSD: Unrecognized NFS CB status value: %u\n", status); 223 return -status; 224 } 225 226 static int decode_cb_op_status(struct xdr_stream *xdr, enum nfs_opnum4 expected, 227 int *status) 228 { 229 __be32 *p; 230 u32 op; 231 232 p = xdr_inline_decode(xdr, 4 + 4); 233 if (unlikely(p == NULL)) 234 goto out_overflow; 235 op = be32_to_cpup(p++); 236 if (unlikely(op != expected)) 237 goto out_unexpected; 238 *status = nfs_cb_stat_to_errno(be32_to_cpup(p)); 239 return 0; 240 out_overflow: 241 print_overflow_msg(__func__, xdr); 242 return -EIO; 243 out_unexpected: 244 dprintk("NFSD: Callback server returned operation %d but " 245 "we issued a request for %d\n", op, expected); 246 return -EIO; 247 } 248 249 /* 250 * CB_COMPOUND4args 251 * 252 * struct CB_COMPOUND4args { 253 * utf8str_cs tag; 254 * uint32_t minorversion; 255 * uint32_t callback_ident; 256 * nfs_cb_argop4 argarray<>; 257 * }; 258 */ 259 static void encode_cb_compound4args(struct xdr_stream *xdr, 260 struct nfs4_cb_compound_hdr *hdr) 261 { 262 __be32 * p; 263 264 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 265 p = xdr_encode_empty_array(p); /* empty tag */ 266 *p++ = cpu_to_be32(hdr->minorversion); 267 *p++ = cpu_to_be32(hdr->ident); 268 269 hdr->nops_p = p; 270 *p = cpu_to_be32(hdr->nops); /* argarray element count */ 271 } 272 273 /* 274 * Update argarray element count 275 */ 276 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr) 277 { 278 BUG_ON(hdr->nops > NFS4_MAX_BACK_CHANNEL_OPS); 279 *hdr->nops_p = cpu_to_be32(hdr->nops); 280 } 281 282 /* 283 * CB_COMPOUND4res 284 * 285 * struct CB_COMPOUND4res { 286 * nfsstat4 status; 287 * utf8str_cs tag; 288 * nfs_cb_resop4 resarray<>; 289 * }; 290 */ 291 static int decode_cb_compound4res(struct xdr_stream *xdr, 292 struct nfs4_cb_compound_hdr *hdr) 293 { 294 u32 length; 295 __be32 *p; 296 297 p = xdr_inline_decode(xdr, 4 + 4); 298 if (unlikely(p == NULL)) 299 goto out_overflow; 300 hdr->status = be32_to_cpup(p++); 301 /* Ignore the tag */ 302 length = be32_to_cpup(p++); 303 p = xdr_inline_decode(xdr, length + 4); 304 if (unlikely(p == NULL)) 305 goto out_overflow; 306 p += XDR_QUADLEN(length); 307 hdr->nops = be32_to_cpup(p); 308 return 0; 309 out_overflow: 310 print_overflow_msg(__func__, xdr); 311 return -EIO; 312 } 313 314 /* 315 * CB_RECALL4args 316 * 317 * struct CB_RECALL4args { 318 * stateid4 stateid; 319 * bool truncate; 320 * nfs_fh4 fh; 321 * }; 322 */ 323 static void encode_cb_recall4args(struct xdr_stream *xdr, 324 const struct nfs4_delegation *dp, 325 struct nfs4_cb_compound_hdr *hdr) 326 { 327 __be32 *p; 328 329 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL); 330 encode_stateid4(xdr, &dp->dl_stid.sc_stateid); 331 332 p = xdr_reserve_space(xdr, 4); 333 *p++ = xdr_zero; /* truncate */ 334 335 encode_nfs_fh4(xdr, &dp->dl_stid.sc_file->fi_fhandle); 336 337 hdr->nops++; 338 } 339 340 /* 341 * CB_SEQUENCE4args 342 * 343 * struct CB_SEQUENCE4args { 344 * sessionid4 csa_sessionid; 345 * sequenceid4 csa_sequenceid; 346 * slotid4 csa_slotid; 347 * slotid4 csa_highest_slotid; 348 * bool csa_cachethis; 349 * referring_call_list4 csa_referring_call_lists<>; 350 * }; 351 */ 352 static void encode_cb_sequence4args(struct xdr_stream *xdr, 353 const struct nfsd4_callback *cb, 354 struct nfs4_cb_compound_hdr *hdr) 355 { 356 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 357 __be32 *p; 358 359 if (hdr->minorversion == 0) 360 return; 361 362 encode_nfs_cb_opnum4(xdr, OP_CB_SEQUENCE); 363 encode_sessionid4(xdr, session); 364 365 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4 + 4); 366 *p++ = cpu_to_be32(session->se_cb_seq_nr); /* csa_sequenceid */ 367 *p++ = xdr_zero; /* csa_slotid */ 368 *p++ = xdr_zero; /* csa_highest_slotid */ 369 *p++ = xdr_zero; /* csa_cachethis */ 370 xdr_encode_empty_array(p); /* csa_referring_call_lists */ 371 372 hdr->nops++; 373 } 374 375 /* 376 * CB_SEQUENCE4resok 377 * 378 * struct CB_SEQUENCE4resok { 379 * sessionid4 csr_sessionid; 380 * sequenceid4 csr_sequenceid; 381 * slotid4 csr_slotid; 382 * slotid4 csr_highest_slotid; 383 * slotid4 csr_target_highest_slotid; 384 * }; 385 * 386 * union CB_SEQUENCE4res switch (nfsstat4 csr_status) { 387 * case NFS4_OK: 388 * CB_SEQUENCE4resok csr_resok4; 389 * default: 390 * void; 391 * }; 392 * 393 * Our current back channel implmentation supports a single backchannel 394 * with a single slot. 395 */ 396 static int decode_cb_sequence4resok(struct xdr_stream *xdr, 397 struct nfsd4_callback *cb) 398 { 399 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 400 int status = -ESERVERFAULT; 401 __be32 *p; 402 u32 dummy; 403 404 /* 405 * If the server returns different values for sessionID, slotID or 406 * sequence number, the server is looney tunes. 407 */ 408 p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4); 409 if (unlikely(p == NULL)) 410 goto out_overflow; 411 412 if (memcmp(p, session->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) { 413 dprintk("NFS: %s Invalid session id\n", __func__); 414 goto out; 415 } 416 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN); 417 418 dummy = be32_to_cpup(p++); 419 if (dummy != session->se_cb_seq_nr) { 420 dprintk("NFS: %s Invalid sequence number\n", __func__); 421 goto out; 422 } 423 424 dummy = be32_to_cpup(p++); 425 if (dummy != 0) { 426 dprintk("NFS: %s Invalid slotid\n", __func__); 427 goto out; 428 } 429 430 /* 431 * FIXME: process highest slotid and target highest slotid 432 */ 433 status = 0; 434 out: 435 cb->cb_seq_status = status; 436 return status; 437 out_overflow: 438 print_overflow_msg(__func__, xdr); 439 status = -EIO; 440 goto out; 441 } 442 443 static int decode_cb_sequence4res(struct xdr_stream *xdr, 444 struct nfsd4_callback *cb) 445 { 446 int status; 447 448 if (cb->cb_clp->cl_minorversion == 0) 449 return 0; 450 451 status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status); 452 if (unlikely(status || cb->cb_seq_status)) 453 return status; 454 455 return decode_cb_sequence4resok(xdr, cb); 456 } 457 458 /* 459 * NFSv4.0 and NFSv4.1 XDR encode functions 460 * 461 * NFSv4.0 callback argument types are defined in section 15 of RFC 462 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 463 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 464 * Protocol". 465 */ 466 467 /* 468 * NB: Without this zero space reservation, callbacks over krb5p fail 469 */ 470 static void nfs4_xdr_enc_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 471 const void *__unused) 472 { 473 xdr_reserve_space(xdr, 0); 474 } 475 476 /* 477 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 478 */ 479 static void nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, struct xdr_stream *xdr, 480 const void *data) 481 { 482 const struct nfsd4_callback *cb = data; 483 const struct nfs4_delegation *dp = cb_to_delegation(cb); 484 struct nfs4_cb_compound_hdr hdr = { 485 .ident = cb->cb_clp->cl_cb_ident, 486 .minorversion = cb->cb_clp->cl_minorversion, 487 }; 488 489 encode_cb_compound4args(xdr, &hdr); 490 encode_cb_sequence4args(xdr, cb, &hdr); 491 encode_cb_recall4args(xdr, dp, &hdr); 492 encode_cb_nops(&hdr); 493 } 494 495 496 /* 497 * NFSv4.0 and NFSv4.1 XDR decode functions 498 * 499 * NFSv4.0 callback result types are defined in section 15 of RFC 500 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 501 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 502 * Protocol". 503 */ 504 505 static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 506 void *__unused) 507 { 508 return 0; 509 } 510 511 /* 512 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 513 */ 514 static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, 515 struct xdr_stream *xdr, 516 void *data) 517 { 518 struct nfsd4_callback *cb = data; 519 struct nfs4_cb_compound_hdr hdr; 520 int status; 521 522 status = decode_cb_compound4res(xdr, &hdr); 523 if (unlikely(status)) 524 return status; 525 526 if (cb != NULL) { 527 status = decode_cb_sequence4res(xdr, cb); 528 if (unlikely(status || cb->cb_seq_status)) 529 return status; 530 } 531 532 return decode_cb_op_status(xdr, OP_CB_RECALL, &cb->cb_status); 533 } 534 535 #ifdef CONFIG_NFSD_PNFS 536 /* 537 * CB_LAYOUTRECALL4args 538 * 539 * struct layoutrecall_file4 { 540 * nfs_fh4 lor_fh; 541 * offset4 lor_offset; 542 * length4 lor_length; 543 * stateid4 lor_stateid; 544 * }; 545 * 546 * union layoutrecall4 switch(layoutrecall_type4 lor_recalltype) { 547 * case LAYOUTRECALL4_FILE: 548 * layoutrecall_file4 lor_layout; 549 * case LAYOUTRECALL4_FSID: 550 * fsid4 lor_fsid; 551 * case LAYOUTRECALL4_ALL: 552 * void; 553 * }; 554 * 555 * struct CB_LAYOUTRECALL4args { 556 * layouttype4 clora_type; 557 * layoutiomode4 clora_iomode; 558 * bool clora_changed; 559 * layoutrecall4 clora_recall; 560 * }; 561 */ 562 static void encode_cb_layout4args(struct xdr_stream *xdr, 563 const struct nfs4_layout_stateid *ls, 564 struct nfs4_cb_compound_hdr *hdr) 565 { 566 __be32 *p; 567 568 BUG_ON(hdr->minorversion == 0); 569 570 p = xdr_reserve_space(xdr, 5 * 4); 571 *p++ = cpu_to_be32(OP_CB_LAYOUTRECALL); 572 *p++ = cpu_to_be32(ls->ls_layout_type); 573 *p++ = cpu_to_be32(IOMODE_ANY); 574 *p++ = cpu_to_be32(1); 575 *p = cpu_to_be32(RETURN_FILE); 576 577 encode_nfs_fh4(xdr, &ls->ls_stid.sc_file->fi_fhandle); 578 579 p = xdr_reserve_space(xdr, 2 * 8); 580 p = xdr_encode_hyper(p, 0); 581 xdr_encode_hyper(p, NFS4_MAX_UINT64); 582 583 encode_stateid4(xdr, &ls->ls_recall_sid); 584 585 hdr->nops++; 586 } 587 588 static void nfs4_xdr_enc_cb_layout(struct rpc_rqst *req, 589 struct xdr_stream *xdr, 590 const void *data) 591 { 592 const struct nfsd4_callback *cb = data; 593 const struct nfs4_layout_stateid *ls = 594 container_of(cb, struct nfs4_layout_stateid, ls_recall); 595 struct nfs4_cb_compound_hdr hdr = { 596 .ident = 0, 597 .minorversion = cb->cb_clp->cl_minorversion, 598 }; 599 600 encode_cb_compound4args(xdr, &hdr); 601 encode_cb_sequence4args(xdr, cb, &hdr); 602 encode_cb_layout4args(xdr, ls, &hdr); 603 encode_cb_nops(&hdr); 604 } 605 606 static int nfs4_xdr_dec_cb_layout(struct rpc_rqst *rqstp, 607 struct xdr_stream *xdr, 608 void *data) 609 { 610 struct nfsd4_callback *cb = data; 611 struct nfs4_cb_compound_hdr hdr; 612 int status; 613 614 status = decode_cb_compound4res(xdr, &hdr); 615 if (unlikely(status)) 616 return status; 617 618 if (cb) { 619 status = decode_cb_sequence4res(xdr, cb); 620 if (unlikely(status || cb->cb_seq_status)) 621 return status; 622 } 623 return decode_cb_op_status(xdr, OP_CB_LAYOUTRECALL, &cb->cb_status); 624 } 625 #endif /* CONFIG_NFSD_PNFS */ 626 627 static void encode_stateowner(struct xdr_stream *xdr, struct nfs4_stateowner *so) 628 { 629 __be32 *p; 630 631 p = xdr_reserve_space(xdr, 8 + 4 + so->so_owner.len); 632 p = xdr_encode_opaque_fixed(p, &so->so_client->cl_clientid, 8); 633 xdr_encode_opaque(p, so->so_owner.data, so->so_owner.len); 634 } 635 636 static void nfs4_xdr_enc_cb_notify_lock(struct rpc_rqst *req, 637 struct xdr_stream *xdr, 638 const void *data) 639 { 640 const struct nfsd4_callback *cb = data; 641 const struct nfsd4_blocked_lock *nbl = 642 container_of(cb, struct nfsd4_blocked_lock, nbl_cb); 643 struct nfs4_lockowner *lo = (struct nfs4_lockowner *)nbl->nbl_lock.fl_owner; 644 struct nfs4_cb_compound_hdr hdr = { 645 .ident = 0, 646 .minorversion = cb->cb_clp->cl_minorversion, 647 }; 648 649 __be32 *p; 650 651 BUG_ON(hdr.minorversion == 0); 652 653 encode_cb_compound4args(xdr, &hdr); 654 encode_cb_sequence4args(xdr, cb, &hdr); 655 656 p = xdr_reserve_space(xdr, 4); 657 *p = cpu_to_be32(OP_CB_NOTIFY_LOCK); 658 encode_nfs_fh4(xdr, &nbl->nbl_fh); 659 encode_stateowner(xdr, &lo->lo_owner); 660 hdr.nops++; 661 662 encode_cb_nops(&hdr); 663 } 664 665 static int nfs4_xdr_dec_cb_notify_lock(struct rpc_rqst *rqstp, 666 struct xdr_stream *xdr, 667 void *data) 668 { 669 struct nfsd4_callback *cb = data; 670 struct nfs4_cb_compound_hdr hdr; 671 int status; 672 673 status = decode_cb_compound4res(xdr, &hdr); 674 if (unlikely(status)) 675 return status; 676 677 if (cb) { 678 status = decode_cb_sequence4res(xdr, cb); 679 if (unlikely(status || cb->cb_seq_status)) 680 return status; 681 } 682 return decode_cb_op_status(xdr, OP_CB_NOTIFY_LOCK, &cb->cb_status); 683 } 684 685 /* 686 * RPC procedure tables 687 */ 688 #define PROC(proc, call, argtype, restype) \ 689 [NFSPROC4_CLNT_##proc] = { \ 690 .p_proc = NFSPROC4_CB_##call, \ 691 .p_encode = nfs4_xdr_enc_##argtype, \ 692 .p_decode = nfs4_xdr_dec_##restype, \ 693 .p_arglen = NFS4_enc_##argtype##_sz, \ 694 .p_replen = NFS4_dec_##restype##_sz, \ 695 .p_statidx = NFSPROC4_CB_##call, \ 696 .p_name = #proc, \ 697 } 698 699 static const struct rpc_procinfo nfs4_cb_procedures[] = { 700 PROC(CB_NULL, NULL, cb_null, cb_null), 701 PROC(CB_RECALL, COMPOUND, cb_recall, cb_recall), 702 #ifdef CONFIG_NFSD_PNFS 703 PROC(CB_LAYOUT, COMPOUND, cb_layout, cb_layout), 704 #endif 705 PROC(CB_NOTIFY_LOCK, COMPOUND, cb_notify_lock, cb_notify_lock), 706 }; 707 708 static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)]; 709 static const struct rpc_version nfs_cb_version4 = { 710 /* 711 * Note on the callback rpc program version number: despite language in rfc 712 * 5661 section 18.36.3 requiring servers to use 4 in this field, the 713 * official xdr descriptions for both 4.0 and 4.1 specify version 1, and 714 * in practice that appears to be what implementations use. The section 715 * 18.36.3 language is expected to be fixed in an erratum. 716 */ 717 .number = 1, 718 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 719 .procs = nfs4_cb_procedures, 720 .counts = nfs4_cb_counts, 721 }; 722 723 static const struct rpc_version *nfs_cb_version[2] = { 724 [1] = &nfs_cb_version4, 725 }; 726 727 static const struct rpc_program cb_program; 728 729 static struct rpc_stat cb_stats = { 730 .program = &cb_program 731 }; 732 733 #define NFS4_CALLBACK 0x40000000 734 static const struct rpc_program cb_program = { 735 .name = "nfs4_cb", 736 .number = NFS4_CALLBACK, 737 .nrvers = ARRAY_SIZE(nfs_cb_version), 738 .version = nfs_cb_version, 739 .stats = &cb_stats, 740 .pipe_dir_name = "nfsd4_cb", 741 }; 742 743 static int max_cb_time(struct net *net) 744 { 745 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 746 return max(nn->nfsd4_lease/10, (time_t)1) * HZ; 747 } 748 749 static struct rpc_cred *callback_cred; 750 751 int set_callback_cred(void) 752 { 753 if (callback_cred) 754 return 0; 755 callback_cred = rpc_lookup_machine_cred("nfs"); 756 if (!callback_cred) 757 return -ENOMEM; 758 return 0; 759 } 760 761 void cleanup_callback_cred(void) 762 { 763 if (callback_cred) { 764 put_rpccred(callback_cred); 765 callback_cred = NULL; 766 } 767 } 768 769 static struct rpc_cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc_clnt *client, struct nfsd4_session *ses) 770 { 771 if (clp->cl_minorversion == 0) { 772 return get_rpccred(callback_cred); 773 } else { 774 struct rpc_auth *auth = client->cl_auth; 775 struct auth_cred acred = {}; 776 777 acred.uid = ses->se_cb_sec.uid; 778 acred.gid = ses->se_cb_sec.gid; 779 return auth->au_ops->lookup_cred(client->cl_auth, &acred, 0); 780 } 781 } 782 783 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses) 784 { 785 int maxtime = max_cb_time(clp->net); 786 struct rpc_timeout timeparms = { 787 .to_initval = maxtime, 788 .to_retries = 0, 789 .to_maxval = maxtime, 790 }; 791 struct rpc_create_args args = { 792 .net = clp->net, 793 .address = (struct sockaddr *) &conn->cb_addr, 794 .addrsize = conn->cb_addrlen, 795 .saddress = (struct sockaddr *) &conn->cb_saddr, 796 .timeout = &timeparms, 797 .program = &cb_program, 798 .version = 1, 799 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), 800 }; 801 struct rpc_clnt *client; 802 struct rpc_cred *cred; 803 804 if (clp->cl_minorversion == 0) { 805 if (!clp->cl_cred.cr_principal && 806 (clp->cl_cred.cr_flavor >= RPC_AUTH_GSS_KRB5)) 807 return -EINVAL; 808 args.client_name = clp->cl_cred.cr_principal; 809 args.prognumber = conn->cb_prog; 810 args.protocol = XPRT_TRANSPORT_TCP; 811 args.authflavor = clp->cl_cred.cr_flavor; 812 clp->cl_cb_ident = conn->cb_ident; 813 } else { 814 if (!conn->cb_xprt) 815 return -EINVAL; 816 clp->cl_cb_conn.cb_xprt = conn->cb_xprt; 817 clp->cl_cb_session = ses; 818 args.bc_xprt = conn->cb_xprt; 819 args.prognumber = clp->cl_cb_session->se_cb_prog; 820 args.protocol = conn->cb_xprt->xpt_class->xcl_ident | 821 XPRT_TRANSPORT_BC; 822 args.authflavor = ses->se_cb_sec.flavor; 823 } 824 /* Create RPC client */ 825 client = rpc_create(&args); 826 if (IS_ERR(client)) { 827 dprintk("NFSD: couldn't create callback client: %ld\n", 828 PTR_ERR(client)); 829 return PTR_ERR(client); 830 } 831 cred = get_backchannel_cred(clp, client, ses); 832 if (IS_ERR(cred)) { 833 rpc_shutdown_client(client); 834 return PTR_ERR(cred); 835 } 836 clp->cl_cb_client = client; 837 clp->cl_cb_cred = cred; 838 return 0; 839 } 840 841 static void warn_no_callback_path(struct nfs4_client *clp, int reason) 842 { 843 dprintk("NFSD: warning: no callback path to client %.*s: error %d\n", 844 (int)clp->cl_name.len, clp->cl_name.data, reason); 845 } 846 847 static void nfsd4_mark_cb_down(struct nfs4_client *clp, int reason) 848 { 849 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 850 return; 851 clp->cl_cb_state = NFSD4_CB_DOWN; 852 warn_no_callback_path(clp, reason); 853 } 854 855 static void nfsd4_mark_cb_fault(struct nfs4_client *clp, int reason) 856 { 857 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 858 return; 859 clp->cl_cb_state = NFSD4_CB_FAULT; 860 warn_no_callback_path(clp, reason); 861 } 862 863 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata) 864 { 865 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 866 867 if (task->tk_status) 868 nfsd4_mark_cb_down(clp, task->tk_status); 869 else 870 clp->cl_cb_state = NFSD4_CB_UP; 871 } 872 873 static const struct rpc_call_ops nfsd4_cb_probe_ops = { 874 /* XXX: release method to ensure we set the cb channel down if 875 * necessary on early failure? */ 876 .rpc_call_done = nfsd4_cb_probe_done, 877 }; 878 879 static struct workqueue_struct *callback_wq; 880 881 /* 882 * Poke the callback thread to process any updates to the callback 883 * parameters, and send a null probe. 884 */ 885 void nfsd4_probe_callback(struct nfs4_client *clp) 886 { 887 clp->cl_cb_state = NFSD4_CB_UNKNOWN; 888 set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 889 nfsd4_run_cb(&clp->cl_cb_null); 890 } 891 892 void nfsd4_probe_callback_sync(struct nfs4_client *clp) 893 { 894 nfsd4_probe_callback(clp); 895 flush_workqueue(callback_wq); 896 } 897 898 void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn) 899 { 900 clp->cl_cb_state = NFSD4_CB_UNKNOWN; 901 spin_lock(&clp->cl_lock); 902 memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn)); 903 spin_unlock(&clp->cl_lock); 904 } 905 906 /* 907 * There's currently a single callback channel slot. 908 * If the slot is available, then mark it busy. Otherwise, set the 909 * thread for sleeping on the callback RPC wait queue. 910 */ 911 static bool nfsd41_cb_get_slot(struct nfs4_client *clp, struct rpc_task *task) 912 { 913 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 914 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL); 915 /* Race breaker */ 916 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 917 dprintk("%s slot is busy\n", __func__); 918 return false; 919 } 920 rpc_wake_up_queued_task(&clp->cl_cb_waitq, task); 921 } 922 return true; 923 } 924 925 /* 926 * TODO: cb_sequence should support referring call lists, cachethis, multiple 927 * slots, and mark callback channel down on communication errors. 928 */ 929 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata) 930 { 931 struct nfsd4_callback *cb = calldata; 932 struct nfs4_client *clp = cb->cb_clp; 933 u32 minorversion = clp->cl_minorversion; 934 935 /* 936 * cb_seq_status is only set in decode_cb_sequence4res, 937 * and so will remain 1 if an rpc level failure occurs. 938 */ 939 cb->cb_seq_status = 1; 940 cb->cb_status = 0; 941 if (minorversion) { 942 if (!nfsd41_cb_get_slot(clp, task)) 943 return; 944 } 945 rpc_call_start(task); 946 } 947 948 static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback *cb) 949 { 950 struct nfs4_client *clp = cb->cb_clp; 951 struct nfsd4_session *session = clp->cl_cb_session; 952 bool ret = true; 953 954 if (!clp->cl_minorversion) { 955 /* 956 * If the backchannel connection was shut down while this 957 * task was queued, we need to resubmit it after setting up 958 * a new backchannel connection. 959 * 960 * Note that if we lost our callback connection permanently 961 * the submission code will error out, so we don't need to 962 * handle that case here. 963 */ 964 if (task->tk_flags & RPC_TASK_KILLED) 965 goto need_restart; 966 967 return true; 968 } 969 970 switch (cb->cb_seq_status) { 971 case 0: 972 /* 973 * No need for lock, access serialized in nfsd4_cb_prepare 974 * 975 * RFC5661 20.9.3 976 * If CB_SEQUENCE returns an error, then the state of the slot 977 * (sequence ID, cached reply) MUST NOT change. 978 */ 979 ++session->se_cb_seq_nr; 980 break; 981 case -ESERVERFAULT: 982 ++session->se_cb_seq_nr; 983 case 1: 984 case -NFS4ERR_BADSESSION: 985 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 986 ret = false; 987 break; 988 case -NFS4ERR_DELAY: 989 if (!rpc_restart_call(task)) 990 goto out; 991 992 rpc_delay(task, 2 * HZ); 993 return false; 994 case -NFS4ERR_BADSLOT: 995 goto retry_nowait; 996 case -NFS4ERR_SEQ_MISORDERED: 997 if (session->se_cb_seq_nr != 1) { 998 session->se_cb_seq_nr = 1; 999 goto retry_nowait; 1000 } 1001 break; 1002 default: 1003 dprintk("%s: unprocessed error %d\n", __func__, 1004 cb->cb_seq_status); 1005 } 1006 1007 clear_bit(0, &clp->cl_cb_slot_busy); 1008 rpc_wake_up_next(&clp->cl_cb_waitq); 1009 dprintk("%s: freed slot, new seqid=%d\n", __func__, 1010 clp->cl_cb_session->se_cb_seq_nr); 1011 1012 if (task->tk_flags & RPC_TASK_KILLED) 1013 goto need_restart; 1014 out: 1015 return ret; 1016 retry_nowait: 1017 if (rpc_restart_call_prepare(task)) 1018 ret = false; 1019 goto out; 1020 need_restart: 1021 task->tk_status = 0; 1022 cb->cb_need_restart = true; 1023 return false; 1024 } 1025 1026 static void nfsd4_cb_done(struct rpc_task *task, void *calldata) 1027 { 1028 struct nfsd4_callback *cb = calldata; 1029 struct nfs4_client *clp = cb->cb_clp; 1030 1031 dprintk("%s: minorversion=%d\n", __func__, 1032 clp->cl_minorversion); 1033 1034 if (!nfsd4_cb_sequence_done(task, cb)) 1035 return; 1036 1037 if (cb->cb_status) { 1038 WARN_ON_ONCE(task->tk_status); 1039 task->tk_status = cb->cb_status; 1040 } 1041 1042 switch (cb->cb_ops->done(cb, task)) { 1043 case 0: 1044 task->tk_status = 0; 1045 rpc_restart_call_prepare(task); 1046 return; 1047 case 1: 1048 break; 1049 case -1: 1050 /* Network partition? */ 1051 nfsd4_mark_cb_down(clp, task->tk_status); 1052 break; 1053 default: 1054 BUG(); 1055 } 1056 } 1057 1058 static void nfsd4_cb_release(void *calldata) 1059 { 1060 struct nfsd4_callback *cb = calldata; 1061 1062 if (cb->cb_need_restart) 1063 nfsd4_run_cb(cb); 1064 else 1065 cb->cb_ops->release(cb); 1066 1067 } 1068 1069 static const struct rpc_call_ops nfsd4_cb_ops = { 1070 .rpc_call_prepare = nfsd4_cb_prepare, 1071 .rpc_call_done = nfsd4_cb_done, 1072 .rpc_release = nfsd4_cb_release, 1073 }; 1074 1075 int nfsd4_create_callback_queue(void) 1076 { 1077 callback_wq = alloc_ordered_workqueue("nfsd4_callbacks", 0); 1078 if (!callback_wq) 1079 return -ENOMEM; 1080 return 0; 1081 } 1082 1083 void nfsd4_destroy_callback_queue(void) 1084 { 1085 destroy_workqueue(callback_wq); 1086 } 1087 1088 /* must be called under the state lock */ 1089 void nfsd4_shutdown_callback(struct nfs4_client *clp) 1090 { 1091 set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); 1092 /* 1093 * Note this won't actually result in a null callback; 1094 * instead, nfsd4_run_cb_null() will detect the killed 1095 * client, destroy the rpc client, and stop: 1096 */ 1097 nfsd4_run_cb(&clp->cl_cb_null); 1098 flush_workqueue(callback_wq); 1099 } 1100 1101 /* requires cl_lock: */ 1102 static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp) 1103 { 1104 struct nfsd4_session *s; 1105 struct nfsd4_conn *c; 1106 1107 list_for_each_entry(s, &clp->cl_sessions, se_perclnt) { 1108 list_for_each_entry(c, &s->se_conns, cn_persession) { 1109 if (c->cn_flags & NFS4_CDFC4_BACK) 1110 return c; 1111 } 1112 } 1113 return NULL; 1114 } 1115 1116 static void nfsd4_process_cb_update(struct nfsd4_callback *cb) 1117 { 1118 struct nfs4_cb_conn conn; 1119 struct nfs4_client *clp = cb->cb_clp; 1120 struct nfsd4_session *ses = NULL; 1121 struct nfsd4_conn *c; 1122 int err; 1123 1124 /* 1125 * This is either an update, or the client dying; in either case, 1126 * kill the old client: 1127 */ 1128 if (clp->cl_cb_client) { 1129 rpc_shutdown_client(clp->cl_cb_client); 1130 clp->cl_cb_client = NULL; 1131 put_rpccred(clp->cl_cb_cred); 1132 clp->cl_cb_cred = NULL; 1133 } 1134 if (clp->cl_cb_conn.cb_xprt) { 1135 svc_xprt_put(clp->cl_cb_conn.cb_xprt); 1136 clp->cl_cb_conn.cb_xprt = NULL; 1137 } 1138 if (test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) 1139 return; 1140 spin_lock(&clp->cl_lock); 1141 /* 1142 * Only serialized callback code is allowed to clear these 1143 * flags; main nfsd code can only set them: 1144 */ 1145 BUG_ON(!(clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK)); 1146 clear_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1147 memcpy(&conn, &cb->cb_clp->cl_cb_conn, sizeof(struct nfs4_cb_conn)); 1148 c = __nfsd4_find_backchannel(clp); 1149 if (c) { 1150 svc_xprt_get(c->cn_xprt); 1151 conn.cb_xprt = c->cn_xprt; 1152 ses = c->cn_session; 1153 } 1154 spin_unlock(&clp->cl_lock); 1155 1156 err = setup_callback_client(clp, &conn, ses); 1157 if (err) { 1158 nfsd4_mark_cb_down(clp, err); 1159 return; 1160 } 1161 } 1162 1163 static void 1164 nfsd4_run_cb_work(struct work_struct *work) 1165 { 1166 struct nfsd4_callback *cb = 1167 container_of(work, struct nfsd4_callback, cb_work); 1168 struct nfs4_client *clp = cb->cb_clp; 1169 struct rpc_clnt *clnt; 1170 1171 if (cb->cb_need_restart) { 1172 cb->cb_need_restart = false; 1173 } else { 1174 if (cb->cb_ops && cb->cb_ops->prepare) 1175 cb->cb_ops->prepare(cb); 1176 } 1177 1178 if (clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK) 1179 nfsd4_process_cb_update(cb); 1180 1181 clnt = clp->cl_cb_client; 1182 if (!clnt) { 1183 /* Callback channel broken, or client killed; give up: */ 1184 if (cb->cb_ops && cb->cb_ops->release) 1185 cb->cb_ops->release(cb); 1186 return; 1187 } 1188 1189 /* 1190 * Don't send probe messages for 4.1 or later. 1191 */ 1192 if (!cb->cb_ops && clp->cl_minorversion) { 1193 clp->cl_cb_state = NFSD4_CB_UP; 1194 return; 1195 } 1196 1197 cb->cb_msg.rpc_cred = clp->cl_cb_cred; 1198 rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN, 1199 cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb); 1200 } 1201 1202 void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, 1203 const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op) 1204 { 1205 cb->cb_clp = clp; 1206 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[op]; 1207 cb->cb_msg.rpc_argp = cb; 1208 cb->cb_msg.rpc_resp = cb; 1209 cb->cb_ops = ops; 1210 INIT_WORK(&cb->cb_work, nfsd4_run_cb_work); 1211 cb->cb_seq_status = 1; 1212 cb->cb_status = 0; 1213 cb->cb_need_restart = false; 1214 } 1215 1216 void nfsd4_run_cb(struct nfsd4_callback *cb) 1217 { 1218 queue_work(callback_wq, &cb->cb_work); 1219 } 1220