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 "trace.h" 42 #include "xdr4cb.h" 43 #include "xdr4.h" 44 45 #define NFSDDBG_FACILITY NFSDDBG_PROC 46 47 static void nfsd4_mark_cb_fault(struct nfs4_client *, int reason); 48 49 #define NFSPROC4_CB_NULL 0 50 #define NFSPROC4_CB_COMPOUND 1 51 52 /* Index of predefined Linux callback client operations */ 53 54 struct nfs4_cb_compound_hdr { 55 /* args */ 56 u32 ident; /* minorversion 0 only */ 57 u32 nops; 58 __be32 *nops_p; 59 u32 minorversion; 60 /* res */ 61 int status; 62 }; 63 64 static __be32 *xdr_encode_empty_array(__be32 *p) 65 { 66 *p++ = xdr_zero; 67 return p; 68 } 69 70 /* 71 * Encode/decode NFSv4 CB basic data types 72 * 73 * Basic NFSv4 callback data types are defined in section 15 of RFC 74 * 3530: "Network File System (NFS) version 4 Protocol" and section 75 * 20 of RFC 5661: "Network File System (NFS) Version 4 Minor Version 76 * 1 Protocol" 77 */ 78 79 static void encode_uint32(struct xdr_stream *xdr, u32 n) 80 { 81 WARN_ON_ONCE(xdr_stream_encode_u32(xdr, n) < 0); 82 } 83 84 static void encode_bitmap4(struct xdr_stream *xdr, const __u32 *bitmap, 85 size_t len) 86 { 87 WARN_ON_ONCE(xdr_stream_encode_uint32_array(xdr, bitmap, len) < 0); 88 } 89 90 /* 91 * nfs_cb_opnum4 92 * 93 * enum nfs_cb_opnum4 { 94 * OP_CB_GETATTR = 3, 95 * ... 96 * }; 97 */ 98 enum nfs_cb_opnum4 { 99 OP_CB_GETATTR = 3, 100 OP_CB_RECALL = 4, 101 OP_CB_LAYOUTRECALL = 5, 102 OP_CB_NOTIFY = 6, 103 OP_CB_PUSH_DELEG = 7, 104 OP_CB_RECALL_ANY = 8, 105 OP_CB_RECALLABLE_OBJ_AVAIL = 9, 106 OP_CB_RECALL_SLOT = 10, 107 OP_CB_SEQUENCE = 11, 108 OP_CB_WANTS_CANCELLED = 12, 109 OP_CB_NOTIFY_LOCK = 13, 110 OP_CB_NOTIFY_DEVICEID = 14, 111 OP_CB_OFFLOAD = 15, 112 OP_CB_ILLEGAL = 10044 113 }; 114 115 static void encode_nfs_cb_opnum4(struct xdr_stream *xdr, enum nfs_cb_opnum4 op) 116 { 117 __be32 *p; 118 119 p = xdr_reserve_space(xdr, 4); 120 *p = cpu_to_be32(op); 121 } 122 123 /* 124 * nfs_fh4 125 * 126 * typedef opaque nfs_fh4<NFS4_FHSIZE>; 127 */ 128 static void encode_nfs_fh4(struct xdr_stream *xdr, const struct knfsd_fh *fh) 129 { 130 u32 length = fh->fh_size; 131 __be32 *p; 132 133 BUG_ON(length > NFS4_FHSIZE); 134 p = xdr_reserve_space(xdr, 4 + length); 135 xdr_encode_opaque(p, &fh->fh_raw, length); 136 } 137 138 /* 139 * stateid4 140 * 141 * struct stateid4 { 142 * uint32_t seqid; 143 * opaque other[12]; 144 * }; 145 */ 146 static void encode_stateid4(struct xdr_stream *xdr, const stateid_t *sid) 147 { 148 __be32 *p; 149 150 p = xdr_reserve_space(xdr, NFS4_STATEID_SIZE); 151 *p++ = cpu_to_be32(sid->si_generation); 152 xdr_encode_opaque_fixed(p, &sid->si_opaque, NFS4_STATEID_OTHER_SIZE); 153 } 154 155 /* 156 * sessionid4 157 * 158 * typedef opaque sessionid4[NFS4_SESSIONID_SIZE]; 159 */ 160 static void encode_sessionid4(struct xdr_stream *xdr, 161 const struct nfsd4_session *session) 162 { 163 __be32 *p; 164 165 p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN); 166 xdr_encode_opaque_fixed(p, session->se_sessionid.data, 167 NFS4_MAX_SESSIONID_LEN); 168 } 169 170 /* 171 * nfsstat4 172 */ 173 static const struct { 174 int stat; 175 int errno; 176 } nfs_cb_errtbl[] = { 177 { NFS4_OK, 0 }, 178 { NFS4ERR_PERM, -EPERM }, 179 { NFS4ERR_NOENT, -ENOENT }, 180 { NFS4ERR_IO, -EIO }, 181 { NFS4ERR_NXIO, -ENXIO }, 182 { NFS4ERR_ACCESS, -EACCES }, 183 { NFS4ERR_EXIST, -EEXIST }, 184 { NFS4ERR_XDEV, -EXDEV }, 185 { NFS4ERR_NOTDIR, -ENOTDIR }, 186 { NFS4ERR_ISDIR, -EISDIR }, 187 { NFS4ERR_INVAL, -EINVAL }, 188 { NFS4ERR_FBIG, -EFBIG }, 189 { NFS4ERR_NOSPC, -ENOSPC }, 190 { NFS4ERR_ROFS, -EROFS }, 191 { NFS4ERR_MLINK, -EMLINK }, 192 { NFS4ERR_NAMETOOLONG, -ENAMETOOLONG }, 193 { NFS4ERR_NOTEMPTY, -ENOTEMPTY }, 194 { NFS4ERR_DQUOT, -EDQUOT }, 195 { NFS4ERR_STALE, -ESTALE }, 196 { NFS4ERR_BADHANDLE, -EBADHANDLE }, 197 { NFS4ERR_BAD_COOKIE, -EBADCOOKIE }, 198 { NFS4ERR_NOTSUPP, -ENOTSUPP }, 199 { NFS4ERR_TOOSMALL, -ETOOSMALL }, 200 { NFS4ERR_SERVERFAULT, -ESERVERFAULT }, 201 { NFS4ERR_BADTYPE, -EBADTYPE }, 202 { NFS4ERR_LOCKED, -EAGAIN }, 203 { NFS4ERR_RESOURCE, -EREMOTEIO }, 204 { NFS4ERR_SYMLINK, -ELOOP }, 205 { NFS4ERR_OP_ILLEGAL, -EOPNOTSUPP }, 206 { NFS4ERR_DEADLOCK, -EDEADLK }, 207 { -1, -EIO } 208 }; 209 210 /* 211 * If we cannot translate the error, the recovery routines should 212 * handle it. 213 * 214 * Note: remaining NFSv4 error codes have values > 10000, so should 215 * not conflict with native Linux error codes. 216 */ 217 static int nfs_cb_stat_to_errno(int status) 218 { 219 int i; 220 221 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 222 if (nfs_cb_errtbl[i].stat == status) 223 return nfs_cb_errtbl[i].errno; 224 } 225 226 dprintk("NFSD: Unrecognized NFS CB status value: %u\n", status); 227 return -status; 228 } 229 230 static int decode_cb_op_status(struct xdr_stream *xdr, 231 enum nfs_cb_opnum4 expected, int *status) 232 { 233 __be32 *p; 234 u32 op; 235 236 p = xdr_inline_decode(xdr, 4 + 4); 237 if (unlikely(p == NULL)) 238 goto out_overflow; 239 op = be32_to_cpup(p++); 240 if (unlikely(op != expected)) 241 goto out_unexpected; 242 *status = nfs_cb_stat_to_errno(be32_to_cpup(p)); 243 return 0; 244 out_overflow: 245 return -EIO; 246 out_unexpected: 247 dprintk("NFSD: Callback server returned operation %d but " 248 "we issued a request for %d\n", op, expected); 249 return -EIO; 250 } 251 252 /* 253 * CB_COMPOUND4args 254 * 255 * struct CB_COMPOUND4args { 256 * utf8str_cs tag; 257 * uint32_t minorversion; 258 * uint32_t callback_ident; 259 * nfs_cb_argop4 argarray<>; 260 * }; 261 */ 262 static void encode_cb_compound4args(struct xdr_stream *xdr, 263 struct nfs4_cb_compound_hdr *hdr) 264 { 265 __be32 * p; 266 267 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 268 p = xdr_encode_empty_array(p); /* empty tag */ 269 *p++ = cpu_to_be32(hdr->minorversion); 270 *p++ = cpu_to_be32(hdr->ident); 271 272 hdr->nops_p = p; 273 *p = cpu_to_be32(hdr->nops); /* argarray element count */ 274 } 275 276 /* 277 * Update argarray element count 278 */ 279 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr) 280 { 281 BUG_ON(hdr->nops > NFS4_MAX_BACK_CHANNEL_OPS); 282 *hdr->nops_p = cpu_to_be32(hdr->nops); 283 } 284 285 /* 286 * CB_COMPOUND4res 287 * 288 * struct CB_COMPOUND4res { 289 * nfsstat4 status; 290 * utf8str_cs tag; 291 * nfs_cb_resop4 resarray<>; 292 * }; 293 */ 294 static int decode_cb_compound4res(struct xdr_stream *xdr, 295 struct nfs4_cb_compound_hdr *hdr) 296 { 297 u32 length; 298 __be32 *p; 299 300 p = xdr_inline_decode(xdr, 4 + 4); 301 if (unlikely(p == NULL)) 302 goto out_overflow; 303 hdr->status = be32_to_cpup(p++); 304 /* Ignore the tag */ 305 length = be32_to_cpup(p++); 306 p = xdr_inline_decode(xdr, length + 4); 307 if (unlikely(p == NULL)) 308 goto out_overflow; 309 p += XDR_QUADLEN(length); 310 hdr->nops = be32_to_cpup(p); 311 return 0; 312 out_overflow: 313 return -EIO; 314 } 315 316 /* 317 * CB_RECALL4args 318 * 319 * struct CB_RECALL4args { 320 * stateid4 stateid; 321 * bool truncate; 322 * nfs_fh4 fh; 323 * }; 324 */ 325 static void encode_cb_recall4args(struct xdr_stream *xdr, 326 const struct nfs4_delegation *dp, 327 struct nfs4_cb_compound_hdr *hdr) 328 { 329 __be32 *p; 330 331 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL); 332 encode_stateid4(xdr, &dp->dl_stid.sc_stateid); 333 334 p = xdr_reserve_space(xdr, 4); 335 *p++ = xdr_zero; /* truncate */ 336 337 encode_nfs_fh4(xdr, &dp->dl_stid.sc_file->fi_fhandle); 338 339 hdr->nops++; 340 } 341 342 /* 343 * CB_RECALLANY4args 344 * 345 * struct CB_RECALLANY4args { 346 * uint32_t craa_objects_to_keep; 347 * bitmap4 craa_type_mask; 348 * }; 349 */ 350 static void 351 encode_cb_recallany4args(struct xdr_stream *xdr, 352 struct nfs4_cb_compound_hdr *hdr, struct nfsd4_cb_recall_any *ra) 353 { 354 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL_ANY); 355 encode_uint32(xdr, ra->ra_keep); 356 encode_bitmap4(xdr, ra->ra_bmval, ARRAY_SIZE(ra->ra_bmval)); 357 hdr->nops++; 358 } 359 360 /* 361 * CB_SEQUENCE4args 362 * 363 * struct CB_SEQUENCE4args { 364 * sessionid4 csa_sessionid; 365 * sequenceid4 csa_sequenceid; 366 * slotid4 csa_slotid; 367 * slotid4 csa_highest_slotid; 368 * bool csa_cachethis; 369 * referring_call_list4 csa_referring_call_lists<>; 370 * }; 371 */ 372 static void encode_cb_sequence4args(struct xdr_stream *xdr, 373 const struct nfsd4_callback *cb, 374 struct nfs4_cb_compound_hdr *hdr) 375 { 376 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 377 __be32 *p; 378 379 if (hdr->minorversion == 0) 380 return; 381 382 encode_nfs_cb_opnum4(xdr, OP_CB_SEQUENCE); 383 encode_sessionid4(xdr, session); 384 385 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4 + 4); 386 *p++ = cpu_to_be32(session->se_cb_seq_nr); /* csa_sequenceid */ 387 *p++ = xdr_zero; /* csa_slotid */ 388 *p++ = xdr_zero; /* csa_highest_slotid */ 389 *p++ = xdr_zero; /* csa_cachethis */ 390 xdr_encode_empty_array(p); /* csa_referring_call_lists */ 391 392 hdr->nops++; 393 } 394 395 /* 396 * CB_SEQUENCE4resok 397 * 398 * struct CB_SEQUENCE4resok { 399 * sessionid4 csr_sessionid; 400 * sequenceid4 csr_sequenceid; 401 * slotid4 csr_slotid; 402 * slotid4 csr_highest_slotid; 403 * slotid4 csr_target_highest_slotid; 404 * }; 405 * 406 * union CB_SEQUENCE4res switch (nfsstat4 csr_status) { 407 * case NFS4_OK: 408 * CB_SEQUENCE4resok csr_resok4; 409 * default: 410 * void; 411 * }; 412 * 413 * Our current back channel implmentation supports a single backchannel 414 * with a single slot. 415 */ 416 static int decode_cb_sequence4resok(struct xdr_stream *xdr, 417 struct nfsd4_callback *cb) 418 { 419 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 420 int status = -ESERVERFAULT; 421 __be32 *p; 422 u32 dummy; 423 424 /* 425 * If the server returns different values for sessionID, slotID or 426 * sequence number, the server is looney tunes. 427 */ 428 p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4); 429 if (unlikely(p == NULL)) 430 goto out_overflow; 431 432 if (memcmp(p, session->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) { 433 dprintk("NFS: %s Invalid session id\n", __func__); 434 goto out; 435 } 436 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN); 437 438 dummy = be32_to_cpup(p++); 439 if (dummy != session->se_cb_seq_nr) { 440 dprintk("NFS: %s Invalid sequence number\n", __func__); 441 goto out; 442 } 443 444 dummy = be32_to_cpup(p++); 445 if (dummy != 0) { 446 dprintk("NFS: %s Invalid slotid\n", __func__); 447 goto out; 448 } 449 450 /* 451 * FIXME: process highest slotid and target highest slotid 452 */ 453 status = 0; 454 out: 455 cb->cb_seq_status = status; 456 return status; 457 out_overflow: 458 status = -EIO; 459 goto out; 460 } 461 462 static int decode_cb_sequence4res(struct xdr_stream *xdr, 463 struct nfsd4_callback *cb) 464 { 465 int status; 466 467 if (cb->cb_clp->cl_minorversion == 0) 468 return 0; 469 470 status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status); 471 if (unlikely(status || cb->cb_seq_status)) 472 return status; 473 474 return decode_cb_sequence4resok(xdr, cb); 475 } 476 477 /* 478 * NFSv4.0 and NFSv4.1 XDR encode functions 479 * 480 * NFSv4.0 callback argument types are defined in section 15 of RFC 481 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 482 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 483 * Protocol". 484 */ 485 486 /* 487 * NB: Without this zero space reservation, callbacks over krb5p fail 488 */ 489 static void nfs4_xdr_enc_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 490 const void *__unused) 491 { 492 xdr_reserve_space(xdr, 0); 493 } 494 495 /* 496 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 497 */ 498 static void nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, struct xdr_stream *xdr, 499 const void *data) 500 { 501 const struct nfsd4_callback *cb = data; 502 const struct nfs4_delegation *dp = cb_to_delegation(cb); 503 struct nfs4_cb_compound_hdr hdr = { 504 .ident = cb->cb_clp->cl_cb_ident, 505 .minorversion = cb->cb_clp->cl_minorversion, 506 }; 507 508 encode_cb_compound4args(xdr, &hdr); 509 encode_cb_sequence4args(xdr, cb, &hdr); 510 encode_cb_recall4args(xdr, dp, &hdr); 511 encode_cb_nops(&hdr); 512 } 513 514 /* 515 * 20.6. Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects 516 */ 517 static void 518 nfs4_xdr_enc_cb_recall_any(struct rpc_rqst *req, 519 struct xdr_stream *xdr, const void *data) 520 { 521 const struct nfsd4_callback *cb = data; 522 struct nfsd4_cb_recall_any *ra; 523 struct nfs4_cb_compound_hdr hdr = { 524 .ident = cb->cb_clp->cl_cb_ident, 525 .minorversion = cb->cb_clp->cl_minorversion, 526 }; 527 528 ra = container_of(cb, struct nfsd4_cb_recall_any, ra_cb); 529 encode_cb_compound4args(xdr, &hdr); 530 encode_cb_sequence4args(xdr, cb, &hdr); 531 encode_cb_recallany4args(xdr, &hdr, ra); 532 encode_cb_nops(&hdr); 533 } 534 535 /* 536 * NFSv4.0 and NFSv4.1 XDR decode functions 537 * 538 * NFSv4.0 callback result types are defined in section 15 of RFC 539 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 540 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 541 * Protocol". 542 */ 543 544 static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 545 void *__unused) 546 { 547 return 0; 548 } 549 550 /* 551 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 552 */ 553 static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, 554 struct xdr_stream *xdr, 555 void *data) 556 { 557 struct nfsd4_callback *cb = data; 558 struct nfs4_cb_compound_hdr hdr; 559 int status; 560 561 status = decode_cb_compound4res(xdr, &hdr); 562 if (unlikely(status)) 563 return status; 564 565 status = decode_cb_sequence4res(xdr, cb); 566 if (unlikely(status || cb->cb_seq_status)) 567 return status; 568 569 return decode_cb_op_status(xdr, OP_CB_RECALL, &cb->cb_status); 570 } 571 572 /* 573 * 20.6. Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects 574 */ 575 static int 576 nfs4_xdr_dec_cb_recall_any(struct rpc_rqst *rqstp, 577 struct xdr_stream *xdr, 578 void *data) 579 { 580 struct nfsd4_callback *cb = data; 581 struct nfs4_cb_compound_hdr hdr; 582 int status; 583 584 status = decode_cb_compound4res(xdr, &hdr); 585 if (unlikely(status)) 586 return status; 587 status = decode_cb_sequence4res(xdr, cb); 588 if (unlikely(status || cb->cb_seq_status)) 589 return status; 590 status = decode_cb_op_status(xdr, OP_CB_RECALL_ANY, &cb->cb_status); 591 return status; 592 } 593 594 #ifdef CONFIG_NFSD_PNFS 595 /* 596 * CB_LAYOUTRECALL4args 597 * 598 * struct layoutrecall_file4 { 599 * nfs_fh4 lor_fh; 600 * offset4 lor_offset; 601 * length4 lor_length; 602 * stateid4 lor_stateid; 603 * }; 604 * 605 * union layoutrecall4 switch(layoutrecall_type4 lor_recalltype) { 606 * case LAYOUTRECALL4_FILE: 607 * layoutrecall_file4 lor_layout; 608 * case LAYOUTRECALL4_FSID: 609 * fsid4 lor_fsid; 610 * case LAYOUTRECALL4_ALL: 611 * void; 612 * }; 613 * 614 * struct CB_LAYOUTRECALL4args { 615 * layouttype4 clora_type; 616 * layoutiomode4 clora_iomode; 617 * bool clora_changed; 618 * layoutrecall4 clora_recall; 619 * }; 620 */ 621 static void encode_cb_layout4args(struct xdr_stream *xdr, 622 const struct nfs4_layout_stateid *ls, 623 struct nfs4_cb_compound_hdr *hdr) 624 { 625 __be32 *p; 626 627 BUG_ON(hdr->minorversion == 0); 628 629 p = xdr_reserve_space(xdr, 5 * 4); 630 *p++ = cpu_to_be32(OP_CB_LAYOUTRECALL); 631 *p++ = cpu_to_be32(ls->ls_layout_type); 632 *p++ = cpu_to_be32(IOMODE_ANY); 633 *p++ = cpu_to_be32(1); 634 *p = cpu_to_be32(RETURN_FILE); 635 636 encode_nfs_fh4(xdr, &ls->ls_stid.sc_file->fi_fhandle); 637 638 p = xdr_reserve_space(xdr, 2 * 8); 639 p = xdr_encode_hyper(p, 0); 640 xdr_encode_hyper(p, NFS4_MAX_UINT64); 641 642 encode_stateid4(xdr, &ls->ls_recall_sid); 643 644 hdr->nops++; 645 } 646 647 static void nfs4_xdr_enc_cb_layout(struct rpc_rqst *req, 648 struct xdr_stream *xdr, 649 const void *data) 650 { 651 const struct nfsd4_callback *cb = data; 652 const struct nfs4_layout_stateid *ls = 653 container_of(cb, struct nfs4_layout_stateid, ls_recall); 654 struct nfs4_cb_compound_hdr hdr = { 655 .ident = 0, 656 .minorversion = cb->cb_clp->cl_minorversion, 657 }; 658 659 encode_cb_compound4args(xdr, &hdr); 660 encode_cb_sequence4args(xdr, cb, &hdr); 661 encode_cb_layout4args(xdr, ls, &hdr); 662 encode_cb_nops(&hdr); 663 } 664 665 static int nfs4_xdr_dec_cb_layout(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 status = decode_cb_sequence4res(xdr, cb); 678 if (unlikely(status || cb->cb_seq_status)) 679 return status; 680 681 return decode_cb_op_status(xdr, OP_CB_LAYOUTRECALL, &cb->cb_status); 682 } 683 #endif /* CONFIG_NFSD_PNFS */ 684 685 static void encode_stateowner(struct xdr_stream *xdr, struct nfs4_stateowner *so) 686 { 687 __be32 *p; 688 689 p = xdr_reserve_space(xdr, 8 + 4 + so->so_owner.len); 690 p = xdr_encode_opaque_fixed(p, &so->so_client->cl_clientid, 8); 691 xdr_encode_opaque(p, so->so_owner.data, so->so_owner.len); 692 } 693 694 static void nfs4_xdr_enc_cb_notify_lock(struct rpc_rqst *req, 695 struct xdr_stream *xdr, 696 const void *data) 697 { 698 const struct nfsd4_callback *cb = data; 699 const struct nfsd4_blocked_lock *nbl = 700 container_of(cb, struct nfsd4_blocked_lock, nbl_cb); 701 struct nfs4_lockowner *lo = (struct nfs4_lockowner *)nbl->nbl_lock.fl_owner; 702 struct nfs4_cb_compound_hdr hdr = { 703 .ident = 0, 704 .minorversion = cb->cb_clp->cl_minorversion, 705 }; 706 707 __be32 *p; 708 709 BUG_ON(hdr.minorversion == 0); 710 711 encode_cb_compound4args(xdr, &hdr); 712 encode_cb_sequence4args(xdr, cb, &hdr); 713 714 p = xdr_reserve_space(xdr, 4); 715 *p = cpu_to_be32(OP_CB_NOTIFY_LOCK); 716 encode_nfs_fh4(xdr, &nbl->nbl_fh); 717 encode_stateowner(xdr, &lo->lo_owner); 718 hdr.nops++; 719 720 encode_cb_nops(&hdr); 721 } 722 723 static int nfs4_xdr_dec_cb_notify_lock(struct rpc_rqst *rqstp, 724 struct xdr_stream *xdr, 725 void *data) 726 { 727 struct nfsd4_callback *cb = data; 728 struct nfs4_cb_compound_hdr hdr; 729 int status; 730 731 status = decode_cb_compound4res(xdr, &hdr); 732 if (unlikely(status)) 733 return status; 734 735 status = decode_cb_sequence4res(xdr, cb); 736 if (unlikely(status || cb->cb_seq_status)) 737 return status; 738 739 return decode_cb_op_status(xdr, OP_CB_NOTIFY_LOCK, &cb->cb_status); 740 } 741 742 /* 743 * struct write_response4 { 744 * stateid4 wr_callback_id<1>; 745 * length4 wr_count; 746 * stable_how4 wr_committed; 747 * verifier4 wr_writeverf; 748 * }; 749 * union offload_info4 switch (nfsstat4 coa_status) { 750 * case NFS4_OK: 751 * write_response4 coa_resok4; 752 * default: 753 * length4 coa_bytes_copied; 754 * }; 755 * struct CB_OFFLOAD4args { 756 * nfs_fh4 coa_fh; 757 * stateid4 coa_stateid; 758 * offload_info4 coa_offload_info; 759 * }; 760 */ 761 static void encode_offload_info4(struct xdr_stream *xdr, 762 const struct nfsd4_cb_offload *cbo) 763 { 764 __be32 *p; 765 766 p = xdr_reserve_space(xdr, 4); 767 *p = cbo->co_nfserr; 768 switch (cbo->co_nfserr) { 769 case nfs_ok: 770 p = xdr_reserve_space(xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE); 771 p = xdr_encode_empty_array(p); 772 p = xdr_encode_hyper(p, cbo->co_res.wr_bytes_written); 773 *p++ = cpu_to_be32(cbo->co_res.wr_stable_how); 774 p = xdr_encode_opaque_fixed(p, cbo->co_res.wr_verifier.data, 775 NFS4_VERIFIER_SIZE); 776 break; 777 default: 778 p = xdr_reserve_space(xdr, 8); 779 /* We always return success if bytes were written */ 780 p = xdr_encode_hyper(p, 0); 781 } 782 } 783 784 static void encode_cb_offload4args(struct xdr_stream *xdr, 785 const struct nfsd4_cb_offload *cbo, 786 struct nfs4_cb_compound_hdr *hdr) 787 { 788 __be32 *p; 789 790 p = xdr_reserve_space(xdr, 4); 791 *p = cpu_to_be32(OP_CB_OFFLOAD); 792 encode_nfs_fh4(xdr, &cbo->co_fh); 793 encode_stateid4(xdr, &cbo->co_res.cb_stateid); 794 encode_offload_info4(xdr, cbo); 795 796 hdr->nops++; 797 } 798 799 static void nfs4_xdr_enc_cb_offload(struct rpc_rqst *req, 800 struct xdr_stream *xdr, 801 const void *data) 802 { 803 const struct nfsd4_callback *cb = data; 804 const struct nfsd4_cb_offload *cbo = 805 container_of(cb, struct nfsd4_cb_offload, co_cb); 806 struct nfs4_cb_compound_hdr hdr = { 807 .ident = 0, 808 .minorversion = cb->cb_clp->cl_minorversion, 809 }; 810 811 encode_cb_compound4args(xdr, &hdr); 812 encode_cb_sequence4args(xdr, cb, &hdr); 813 encode_cb_offload4args(xdr, cbo, &hdr); 814 encode_cb_nops(&hdr); 815 } 816 817 static int nfs4_xdr_dec_cb_offload(struct rpc_rqst *rqstp, 818 struct xdr_stream *xdr, 819 void *data) 820 { 821 struct nfsd4_callback *cb = data; 822 struct nfs4_cb_compound_hdr hdr; 823 int status; 824 825 status = decode_cb_compound4res(xdr, &hdr); 826 if (unlikely(status)) 827 return status; 828 829 status = decode_cb_sequence4res(xdr, cb); 830 if (unlikely(status || cb->cb_seq_status)) 831 return status; 832 833 return decode_cb_op_status(xdr, OP_CB_OFFLOAD, &cb->cb_status); 834 } 835 /* 836 * RPC procedure tables 837 */ 838 #define PROC(proc, call, argtype, restype) \ 839 [NFSPROC4_CLNT_##proc] = { \ 840 .p_proc = NFSPROC4_CB_##call, \ 841 .p_encode = nfs4_xdr_enc_##argtype, \ 842 .p_decode = nfs4_xdr_dec_##restype, \ 843 .p_arglen = NFS4_enc_##argtype##_sz, \ 844 .p_replen = NFS4_dec_##restype##_sz, \ 845 .p_statidx = NFSPROC4_CB_##call, \ 846 .p_name = #proc, \ 847 } 848 849 static const struct rpc_procinfo nfs4_cb_procedures[] = { 850 PROC(CB_NULL, NULL, cb_null, cb_null), 851 PROC(CB_RECALL, COMPOUND, cb_recall, cb_recall), 852 #ifdef CONFIG_NFSD_PNFS 853 PROC(CB_LAYOUT, COMPOUND, cb_layout, cb_layout), 854 #endif 855 PROC(CB_NOTIFY_LOCK, COMPOUND, cb_notify_lock, cb_notify_lock), 856 PROC(CB_OFFLOAD, COMPOUND, cb_offload, cb_offload), 857 PROC(CB_RECALL_ANY, COMPOUND, cb_recall_any, cb_recall_any), 858 }; 859 860 static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)]; 861 static const struct rpc_version nfs_cb_version4 = { 862 /* 863 * Note on the callback rpc program version number: despite language in rfc 864 * 5661 section 18.36.3 requiring servers to use 4 in this field, the 865 * official xdr descriptions for both 4.0 and 4.1 specify version 1, and 866 * in practice that appears to be what implementations use. The section 867 * 18.36.3 language is expected to be fixed in an erratum. 868 */ 869 .number = 1, 870 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 871 .procs = nfs4_cb_procedures, 872 .counts = nfs4_cb_counts, 873 }; 874 875 static const struct rpc_version *nfs_cb_version[2] = { 876 [1] = &nfs_cb_version4, 877 }; 878 879 static const struct rpc_program cb_program; 880 881 static struct rpc_stat cb_stats = { 882 .program = &cb_program 883 }; 884 885 #define NFS4_CALLBACK 0x40000000 886 static const struct rpc_program cb_program = { 887 .name = "nfs4_cb", 888 .number = NFS4_CALLBACK, 889 .nrvers = ARRAY_SIZE(nfs_cb_version), 890 .version = nfs_cb_version, 891 .stats = &cb_stats, 892 .pipe_dir_name = "nfsd4_cb", 893 }; 894 895 static int max_cb_time(struct net *net) 896 { 897 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 898 899 /* 900 * nfsd4_lease is set to at most one hour in __nfsd4_write_time, 901 * so we can use 32-bit math on it. Warn if that assumption 902 * ever stops being true. 903 */ 904 if (WARN_ON_ONCE(nn->nfsd4_lease > 3600)) 905 return 360 * HZ; 906 907 return max(((u32)nn->nfsd4_lease)/10, 1u) * HZ; 908 } 909 910 static struct workqueue_struct *callback_wq; 911 912 static bool nfsd4_queue_cb(struct nfsd4_callback *cb) 913 { 914 return queue_work(callback_wq, &cb->cb_work); 915 } 916 917 static void nfsd41_cb_inflight_begin(struct nfs4_client *clp) 918 { 919 atomic_inc(&clp->cl_cb_inflight); 920 } 921 922 static void nfsd41_cb_inflight_end(struct nfs4_client *clp) 923 { 924 925 if (atomic_dec_and_test(&clp->cl_cb_inflight)) 926 wake_up_var(&clp->cl_cb_inflight); 927 } 928 929 static void nfsd41_cb_inflight_wait_complete(struct nfs4_client *clp) 930 { 931 wait_var_event(&clp->cl_cb_inflight, 932 !atomic_read(&clp->cl_cb_inflight)); 933 } 934 935 static const struct cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc_clnt *client, struct nfsd4_session *ses) 936 { 937 if (clp->cl_minorversion == 0) { 938 client->cl_principal = clp->cl_cred.cr_targ_princ ? 939 clp->cl_cred.cr_targ_princ : "nfs"; 940 941 return get_cred(rpc_machine_cred()); 942 } else { 943 struct cred *kcred; 944 945 kcred = prepare_kernel_cred(&init_task); 946 if (!kcred) 947 return NULL; 948 949 kcred->uid = ses->se_cb_sec.uid; 950 kcred->gid = ses->se_cb_sec.gid; 951 return kcred; 952 } 953 } 954 955 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses) 956 { 957 int maxtime = max_cb_time(clp->net); 958 struct rpc_timeout timeparms = { 959 .to_initval = maxtime, 960 .to_retries = 0, 961 .to_maxval = maxtime, 962 }; 963 struct rpc_create_args args = { 964 .net = clp->net, 965 .address = (struct sockaddr *) &conn->cb_addr, 966 .addrsize = conn->cb_addrlen, 967 .saddress = (struct sockaddr *) &conn->cb_saddr, 968 .timeout = &timeparms, 969 .program = &cb_program, 970 .version = 1, 971 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), 972 .cred = current_cred(), 973 }; 974 struct rpc_clnt *client; 975 const struct cred *cred; 976 977 if (clp->cl_minorversion == 0) { 978 if (!clp->cl_cred.cr_principal && 979 (clp->cl_cred.cr_flavor >= RPC_AUTH_GSS_KRB5)) { 980 trace_nfsd_cb_setup_err(clp, -EINVAL); 981 return -EINVAL; 982 } 983 args.client_name = clp->cl_cred.cr_principal; 984 args.prognumber = conn->cb_prog; 985 args.protocol = XPRT_TRANSPORT_TCP; 986 args.authflavor = clp->cl_cred.cr_flavor; 987 clp->cl_cb_ident = conn->cb_ident; 988 } else { 989 if (!conn->cb_xprt) 990 return -EINVAL; 991 clp->cl_cb_session = ses; 992 args.bc_xprt = conn->cb_xprt; 993 args.prognumber = clp->cl_cb_session->se_cb_prog; 994 args.protocol = conn->cb_xprt->xpt_class->xcl_ident | 995 XPRT_TRANSPORT_BC; 996 args.authflavor = ses->se_cb_sec.flavor; 997 } 998 /* Create RPC client */ 999 client = rpc_create(&args); 1000 if (IS_ERR(client)) { 1001 trace_nfsd_cb_setup_err(clp, PTR_ERR(client)); 1002 return PTR_ERR(client); 1003 } 1004 cred = get_backchannel_cred(clp, client, ses); 1005 if (!cred) { 1006 trace_nfsd_cb_setup_err(clp, -ENOMEM); 1007 rpc_shutdown_client(client); 1008 return -ENOMEM; 1009 } 1010 1011 if (clp->cl_minorversion != 0) 1012 clp->cl_cb_conn.cb_xprt = conn->cb_xprt; 1013 clp->cl_cb_client = client; 1014 clp->cl_cb_cred = cred; 1015 rcu_read_lock(); 1016 trace_nfsd_cb_setup(clp, rpc_peeraddr2str(client, RPC_DISPLAY_NETID), 1017 args.authflavor); 1018 rcu_read_unlock(); 1019 return 0; 1020 } 1021 1022 static void nfsd4_mark_cb_state(struct nfs4_client *clp, int newstate) 1023 { 1024 if (clp->cl_cb_state != newstate) { 1025 clp->cl_cb_state = newstate; 1026 trace_nfsd_cb_state(clp); 1027 } 1028 } 1029 1030 static void nfsd4_mark_cb_down(struct nfs4_client *clp, int reason) 1031 { 1032 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 1033 return; 1034 nfsd4_mark_cb_state(clp, NFSD4_CB_DOWN); 1035 } 1036 1037 static void nfsd4_mark_cb_fault(struct nfs4_client *clp, int reason) 1038 { 1039 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 1040 return; 1041 nfsd4_mark_cb_state(clp, NFSD4_CB_FAULT); 1042 } 1043 1044 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata) 1045 { 1046 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 1047 1048 if (task->tk_status) 1049 nfsd4_mark_cb_down(clp, task->tk_status); 1050 else 1051 nfsd4_mark_cb_state(clp, NFSD4_CB_UP); 1052 } 1053 1054 static void nfsd4_cb_probe_release(void *calldata) 1055 { 1056 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 1057 1058 nfsd41_cb_inflight_end(clp); 1059 1060 } 1061 1062 static const struct rpc_call_ops nfsd4_cb_probe_ops = { 1063 /* XXX: release method to ensure we set the cb channel down if 1064 * necessary on early failure? */ 1065 .rpc_call_done = nfsd4_cb_probe_done, 1066 .rpc_release = nfsd4_cb_probe_release, 1067 }; 1068 1069 /* 1070 * Poke the callback thread to process any updates to the callback 1071 * parameters, and send a null probe. 1072 */ 1073 void nfsd4_probe_callback(struct nfs4_client *clp) 1074 { 1075 trace_nfsd_cb_probe(clp); 1076 nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN); 1077 set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1078 nfsd4_run_cb(&clp->cl_cb_null); 1079 } 1080 1081 void nfsd4_probe_callback_sync(struct nfs4_client *clp) 1082 { 1083 nfsd4_probe_callback(clp); 1084 flush_workqueue(callback_wq); 1085 } 1086 1087 void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn) 1088 { 1089 nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN); 1090 spin_lock(&clp->cl_lock); 1091 memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn)); 1092 spin_unlock(&clp->cl_lock); 1093 } 1094 1095 /* 1096 * There's currently a single callback channel slot. 1097 * If the slot is available, then mark it busy. Otherwise, set the 1098 * thread for sleeping on the callback RPC wait queue. 1099 */ 1100 static bool nfsd41_cb_get_slot(struct nfsd4_callback *cb, struct rpc_task *task) 1101 { 1102 struct nfs4_client *clp = cb->cb_clp; 1103 1104 if (!cb->cb_holds_slot && 1105 test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 1106 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL); 1107 /* Race breaker */ 1108 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 1109 dprintk("%s slot is busy\n", __func__); 1110 return false; 1111 } 1112 rpc_wake_up_queued_task(&clp->cl_cb_waitq, task); 1113 } 1114 cb->cb_holds_slot = true; 1115 return true; 1116 } 1117 1118 static void nfsd41_cb_release_slot(struct nfsd4_callback *cb) 1119 { 1120 struct nfs4_client *clp = cb->cb_clp; 1121 1122 if (cb->cb_holds_slot) { 1123 cb->cb_holds_slot = false; 1124 clear_bit(0, &clp->cl_cb_slot_busy); 1125 rpc_wake_up_next(&clp->cl_cb_waitq); 1126 } 1127 } 1128 1129 static void nfsd41_destroy_cb(struct nfsd4_callback *cb) 1130 { 1131 struct nfs4_client *clp = cb->cb_clp; 1132 1133 nfsd41_cb_release_slot(cb); 1134 if (cb->cb_ops && cb->cb_ops->release) 1135 cb->cb_ops->release(cb); 1136 nfsd41_cb_inflight_end(clp); 1137 } 1138 1139 /* 1140 * TODO: cb_sequence should support referring call lists, cachethis, multiple 1141 * slots, and mark callback channel down on communication errors. 1142 */ 1143 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata) 1144 { 1145 struct nfsd4_callback *cb = calldata; 1146 struct nfs4_client *clp = cb->cb_clp; 1147 u32 minorversion = clp->cl_minorversion; 1148 1149 /* 1150 * cb_seq_status is only set in decode_cb_sequence4res, 1151 * and so will remain 1 if an rpc level failure occurs. 1152 */ 1153 cb->cb_seq_status = 1; 1154 cb->cb_status = 0; 1155 if (minorversion && !nfsd41_cb_get_slot(cb, task)) 1156 return; 1157 rpc_call_start(task); 1158 } 1159 1160 static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback *cb) 1161 { 1162 struct nfs4_client *clp = cb->cb_clp; 1163 struct nfsd4_session *session = clp->cl_cb_session; 1164 bool ret = true; 1165 1166 if (!clp->cl_minorversion) { 1167 /* 1168 * If the backchannel connection was shut down while this 1169 * task was queued, we need to resubmit it after setting up 1170 * a new backchannel connection. 1171 * 1172 * Note that if we lost our callback connection permanently 1173 * the submission code will error out, so we don't need to 1174 * handle that case here. 1175 */ 1176 if (RPC_SIGNALLED(task)) 1177 goto need_restart; 1178 1179 return true; 1180 } 1181 1182 if (!cb->cb_holds_slot) 1183 goto need_restart; 1184 1185 switch (cb->cb_seq_status) { 1186 case 0: 1187 /* 1188 * No need for lock, access serialized in nfsd4_cb_prepare 1189 * 1190 * RFC5661 20.9.3 1191 * If CB_SEQUENCE returns an error, then the state of the slot 1192 * (sequence ID, cached reply) MUST NOT change. 1193 */ 1194 ++session->se_cb_seq_nr; 1195 break; 1196 case -ESERVERFAULT: 1197 ++session->se_cb_seq_nr; 1198 fallthrough; 1199 case 1: 1200 case -NFS4ERR_BADSESSION: 1201 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 1202 ret = false; 1203 break; 1204 case -NFS4ERR_DELAY: 1205 if (!rpc_restart_call(task)) 1206 goto out; 1207 1208 rpc_delay(task, 2 * HZ); 1209 return false; 1210 case -NFS4ERR_BADSLOT: 1211 goto retry_nowait; 1212 case -NFS4ERR_SEQ_MISORDERED: 1213 if (session->se_cb_seq_nr != 1) { 1214 session->se_cb_seq_nr = 1; 1215 goto retry_nowait; 1216 } 1217 break; 1218 default: 1219 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 1220 dprintk("%s: unprocessed error %d\n", __func__, 1221 cb->cb_seq_status); 1222 } 1223 1224 nfsd41_cb_release_slot(cb); 1225 dprintk("%s: freed slot, new seqid=%d\n", __func__, 1226 clp->cl_cb_session->se_cb_seq_nr); 1227 1228 if (RPC_SIGNALLED(task)) 1229 goto need_restart; 1230 out: 1231 return ret; 1232 retry_nowait: 1233 if (rpc_restart_call_prepare(task)) 1234 ret = false; 1235 goto out; 1236 need_restart: 1237 if (!test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) { 1238 task->tk_status = 0; 1239 cb->cb_need_restart = true; 1240 } 1241 return false; 1242 } 1243 1244 static void nfsd4_cb_done(struct rpc_task *task, void *calldata) 1245 { 1246 struct nfsd4_callback *cb = calldata; 1247 struct nfs4_client *clp = cb->cb_clp; 1248 1249 if (!nfsd4_cb_sequence_done(task, cb)) 1250 return; 1251 1252 if (cb->cb_status) { 1253 WARN_ON_ONCE(task->tk_status); 1254 task->tk_status = cb->cb_status; 1255 } 1256 1257 switch (cb->cb_ops->done(cb, task)) { 1258 case 0: 1259 task->tk_status = 0; 1260 rpc_restart_call_prepare(task); 1261 return; 1262 case 1: 1263 switch (task->tk_status) { 1264 case -EIO: 1265 case -ETIMEDOUT: 1266 case -EACCES: 1267 nfsd4_mark_cb_down(clp, task->tk_status); 1268 } 1269 break; 1270 default: 1271 BUG(); 1272 } 1273 } 1274 1275 static void nfsd4_cb_release(void *calldata) 1276 { 1277 struct nfsd4_callback *cb = calldata; 1278 1279 if (cb->cb_need_restart) 1280 nfsd4_queue_cb(cb); 1281 else 1282 nfsd41_destroy_cb(cb); 1283 1284 } 1285 1286 static const struct rpc_call_ops nfsd4_cb_ops = { 1287 .rpc_call_prepare = nfsd4_cb_prepare, 1288 .rpc_call_done = nfsd4_cb_done, 1289 .rpc_release = nfsd4_cb_release, 1290 }; 1291 1292 int nfsd4_create_callback_queue(void) 1293 { 1294 callback_wq = alloc_ordered_workqueue("nfsd4_callbacks", 0); 1295 if (!callback_wq) 1296 return -ENOMEM; 1297 return 0; 1298 } 1299 1300 void nfsd4_destroy_callback_queue(void) 1301 { 1302 destroy_workqueue(callback_wq); 1303 } 1304 1305 /* must be called under the state lock */ 1306 void nfsd4_shutdown_callback(struct nfs4_client *clp) 1307 { 1308 if (clp->cl_cb_state != NFSD4_CB_UNKNOWN) 1309 trace_nfsd_cb_shutdown(clp); 1310 1311 set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); 1312 /* 1313 * Note this won't actually result in a null callback; 1314 * instead, nfsd4_run_cb_null() will detect the killed 1315 * client, destroy the rpc client, and stop: 1316 */ 1317 nfsd4_run_cb(&clp->cl_cb_null); 1318 flush_workqueue(callback_wq); 1319 nfsd41_cb_inflight_wait_complete(clp); 1320 } 1321 1322 /* requires cl_lock: */ 1323 static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp) 1324 { 1325 struct nfsd4_session *s; 1326 struct nfsd4_conn *c; 1327 1328 list_for_each_entry(s, &clp->cl_sessions, se_perclnt) { 1329 list_for_each_entry(c, &s->se_conns, cn_persession) { 1330 if (c->cn_flags & NFS4_CDFC4_BACK) 1331 return c; 1332 } 1333 } 1334 return NULL; 1335 } 1336 1337 /* 1338 * Note there isn't a lot of locking in this code; instead we depend on 1339 * the fact that it is run from the callback_wq, which won't run two 1340 * work items at once. So, for example, callback_wq handles all access 1341 * of cl_cb_client and all calls to rpc_create or rpc_shutdown_client. 1342 */ 1343 static void nfsd4_process_cb_update(struct nfsd4_callback *cb) 1344 { 1345 struct nfs4_cb_conn conn; 1346 struct nfs4_client *clp = cb->cb_clp; 1347 struct nfsd4_session *ses = NULL; 1348 struct nfsd4_conn *c; 1349 int err; 1350 1351 /* 1352 * This is either an update, or the client dying; in either case, 1353 * kill the old client: 1354 */ 1355 if (clp->cl_cb_client) { 1356 rpc_shutdown_client(clp->cl_cb_client); 1357 clp->cl_cb_client = NULL; 1358 put_cred(clp->cl_cb_cred); 1359 clp->cl_cb_cred = NULL; 1360 } 1361 if (clp->cl_cb_conn.cb_xprt) { 1362 svc_xprt_put(clp->cl_cb_conn.cb_xprt); 1363 clp->cl_cb_conn.cb_xprt = NULL; 1364 } 1365 if (test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) 1366 return; 1367 spin_lock(&clp->cl_lock); 1368 /* 1369 * Only serialized callback code is allowed to clear these 1370 * flags; main nfsd code can only set them: 1371 */ 1372 BUG_ON(!(clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK)); 1373 clear_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1374 memcpy(&conn, &cb->cb_clp->cl_cb_conn, sizeof(struct nfs4_cb_conn)); 1375 c = __nfsd4_find_backchannel(clp); 1376 if (c) { 1377 svc_xprt_get(c->cn_xprt); 1378 conn.cb_xprt = c->cn_xprt; 1379 ses = c->cn_session; 1380 } 1381 spin_unlock(&clp->cl_lock); 1382 1383 err = setup_callback_client(clp, &conn, ses); 1384 if (err) { 1385 nfsd4_mark_cb_down(clp, err); 1386 if (c) 1387 svc_xprt_put(c->cn_xprt); 1388 return; 1389 } 1390 } 1391 1392 static void 1393 nfsd4_run_cb_work(struct work_struct *work) 1394 { 1395 struct nfsd4_callback *cb = 1396 container_of(work, struct nfsd4_callback, cb_work); 1397 struct nfs4_client *clp = cb->cb_clp; 1398 struct rpc_clnt *clnt; 1399 int flags; 1400 1401 if (cb->cb_need_restart) { 1402 cb->cb_need_restart = false; 1403 } else { 1404 if (cb->cb_ops && cb->cb_ops->prepare) 1405 cb->cb_ops->prepare(cb); 1406 } 1407 1408 if (clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK) 1409 nfsd4_process_cb_update(cb); 1410 1411 clnt = clp->cl_cb_client; 1412 if (!clnt) { 1413 /* Callback channel broken, or client killed; give up: */ 1414 nfsd41_destroy_cb(cb); 1415 return; 1416 } 1417 1418 /* 1419 * Don't send probe messages for 4.1 or later. 1420 */ 1421 if (!cb->cb_ops && clp->cl_minorversion) { 1422 nfsd4_mark_cb_state(clp, NFSD4_CB_UP); 1423 nfsd41_destroy_cb(cb); 1424 return; 1425 } 1426 1427 cb->cb_msg.rpc_cred = clp->cl_cb_cred; 1428 flags = clp->cl_minorversion ? RPC_TASK_NOCONNECT : RPC_TASK_SOFTCONN; 1429 rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | flags, 1430 cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb); 1431 } 1432 1433 void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, 1434 const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op) 1435 { 1436 cb->cb_clp = clp; 1437 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[op]; 1438 cb->cb_msg.rpc_argp = cb; 1439 cb->cb_msg.rpc_resp = cb; 1440 cb->cb_ops = ops; 1441 INIT_WORK(&cb->cb_work, nfsd4_run_cb_work); 1442 cb->cb_seq_status = 1; 1443 cb->cb_status = 0; 1444 cb->cb_need_restart = false; 1445 cb->cb_holds_slot = false; 1446 } 1447 1448 /** 1449 * nfsd4_run_cb - queue up a callback job to run 1450 * @cb: callback to queue 1451 * 1452 * Kick off a callback to do its thing. Returns false if it was already 1453 * on a queue, true otherwise. 1454 */ 1455 bool nfsd4_run_cb(struct nfsd4_callback *cb) 1456 { 1457 struct nfs4_client *clp = cb->cb_clp; 1458 bool queued; 1459 1460 nfsd41_cb_inflight_begin(clp); 1461 queued = nfsd4_queue_cb(cb); 1462 if (!queued) 1463 nfsd41_cb_inflight_end(clp); 1464 return queued; 1465 } 1466