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 /* 80 * nfs_cb_opnum4 81 * 82 * enum nfs_cb_opnum4 { 83 * OP_CB_GETATTR = 3, 84 * ... 85 * }; 86 */ 87 enum nfs_cb_opnum4 { 88 OP_CB_GETATTR = 3, 89 OP_CB_RECALL = 4, 90 OP_CB_LAYOUTRECALL = 5, 91 OP_CB_NOTIFY = 6, 92 OP_CB_PUSH_DELEG = 7, 93 OP_CB_RECALL_ANY = 8, 94 OP_CB_RECALLABLE_OBJ_AVAIL = 9, 95 OP_CB_RECALL_SLOT = 10, 96 OP_CB_SEQUENCE = 11, 97 OP_CB_WANTS_CANCELLED = 12, 98 OP_CB_NOTIFY_LOCK = 13, 99 OP_CB_NOTIFY_DEVICEID = 14, 100 OP_CB_OFFLOAD = 15, 101 OP_CB_ILLEGAL = 10044 102 }; 103 104 static void encode_nfs_cb_opnum4(struct xdr_stream *xdr, enum nfs_cb_opnum4 op) 105 { 106 __be32 *p; 107 108 p = xdr_reserve_space(xdr, 4); 109 *p = cpu_to_be32(op); 110 } 111 112 /* 113 * nfs_fh4 114 * 115 * typedef opaque nfs_fh4<NFS4_FHSIZE>; 116 */ 117 static void encode_nfs_fh4(struct xdr_stream *xdr, const struct knfsd_fh *fh) 118 { 119 u32 length = fh->fh_size; 120 __be32 *p; 121 122 BUG_ON(length > NFS4_FHSIZE); 123 p = xdr_reserve_space(xdr, 4 + length); 124 xdr_encode_opaque(p, &fh->fh_base, length); 125 } 126 127 /* 128 * stateid4 129 * 130 * struct stateid4 { 131 * uint32_t seqid; 132 * opaque other[12]; 133 * }; 134 */ 135 static void encode_stateid4(struct xdr_stream *xdr, const stateid_t *sid) 136 { 137 __be32 *p; 138 139 p = xdr_reserve_space(xdr, NFS4_STATEID_SIZE); 140 *p++ = cpu_to_be32(sid->si_generation); 141 xdr_encode_opaque_fixed(p, &sid->si_opaque, NFS4_STATEID_OTHER_SIZE); 142 } 143 144 /* 145 * sessionid4 146 * 147 * typedef opaque sessionid4[NFS4_SESSIONID_SIZE]; 148 */ 149 static void encode_sessionid4(struct xdr_stream *xdr, 150 const struct nfsd4_session *session) 151 { 152 __be32 *p; 153 154 p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN); 155 xdr_encode_opaque_fixed(p, session->se_sessionid.data, 156 NFS4_MAX_SESSIONID_LEN); 157 } 158 159 /* 160 * nfsstat4 161 */ 162 static const struct { 163 int stat; 164 int errno; 165 } nfs_cb_errtbl[] = { 166 { NFS4_OK, 0 }, 167 { NFS4ERR_PERM, -EPERM }, 168 { NFS4ERR_NOENT, -ENOENT }, 169 { NFS4ERR_IO, -EIO }, 170 { NFS4ERR_NXIO, -ENXIO }, 171 { NFS4ERR_ACCESS, -EACCES }, 172 { NFS4ERR_EXIST, -EEXIST }, 173 { NFS4ERR_XDEV, -EXDEV }, 174 { NFS4ERR_NOTDIR, -ENOTDIR }, 175 { NFS4ERR_ISDIR, -EISDIR }, 176 { NFS4ERR_INVAL, -EINVAL }, 177 { NFS4ERR_FBIG, -EFBIG }, 178 { NFS4ERR_NOSPC, -ENOSPC }, 179 { NFS4ERR_ROFS, -EROFS }, 180 { NFS4ERR_MLINK, -EMLINK }, 181 { NFS4ERR_NAMETOOLONG, -ENAMETOOLONG }, 182 { NFS4ERR_NOTEMPTY, -ENOTEMPTY }, 183 { NFS4ERR_DQUOT, -EDQUOT }, 184 { NFS4ERR_STALE, -ESTALE }, 185 { NFS4ERR_BADHANDLE, -EBADHANDLE }, 186 { NFS4ERR_BAD_COOKIE, -EBADCOOKIE }, 187 { NFS4ERR_NOTSUPP, -ENOTSUPP }, 188 { NFS4ERR_TOOSMALL, -ETOOSMALL }, 189 { NFS4ERR_SERVERFAULT, -ESERVERFAULT }, 190 { NFS4ERR_BADTYPE, -EBADTYPE }, 191 { NFS4ERR_LOCKED, -EAGAIN }, 192 { NFS4ERR_RESOURCE, -EREMOTEIO }, 193 { NFS4ERR_SYMLINK, -ELOOP }, 194 { NFS4ERR_OP_ILLEGAL, -EOPNOTSUPP }, 195 { NFS4ERR_DEADLOCK, -EDEADLK }, 196 { -1, -EIO } 197 }; 198 199 /* 200 * If we cannot translate the error, the recovery routines should 201 * handle it. 202 * 203 * Note: remaining NFSv4 error codes have values > 10000, so should 204 * not conflict with native Linux error codes. 205 */ 206 static int nfs_cb_stat_to_errno(int status) 207 { 208 int i; 209 210 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 211 if (nfs_cb_errtbl[i].stat == status) 212 return nfs_cb_errtbl[i].errno; 213 } 214 215 dprintk("NFSD: Unrecognized NFS CB status value: %u\n", status); 216 return -status; 217 } 218 219 static int decode_cb_op_status(struct xdr_stream *xdr, 220 enum nfs_cb_opnum4 expected, int *status) 221 { 222 __be32 *p; 223 u32 op; 224 225 p = xdr_inline_decode(xdr, 4 + 4); 226 if (unlikely(p == NULL)) 227 goto out_overflow; 228 op = be32_to_cpup(p++); 229 if (unlikely(op != expected)) 230 goto out_unexpected; 231 *status = nfs_cb_stat_to_errno(be32_to_cpup(p)); 232 return 0; 233 out_overflow: 234 return -EIO; 235 out_unexpected: 236 dprintk("NFSD: Callback server returned operation %d but " 237 "we issued a request for %d\n", op, expected); 238 return -EIO; 239 } 240 241 /* 242 * CB_COMPOUND4args 243 * 244 * struct CB_COMPOUND4args { 245 * utf8str_cs tag; 246 * uint32_t minorversion; 247 * uint32_t callback_ident; 248 * nfs_cb_argop4 argarray<>; 249 * }; 250 */ 251 static void encode_cb_compound4args(struct xdr_stream *xdr, 252 struct nfs4_cb_compound_hdr *hdr) 253 { 254 __be32 * p; 255 256 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 257 p = xdr_encode_empty_array(p); /* empty tag */ 258 *p++ = cpu_to_be32(hdr->minorversion); 259 *p++ = cpu_to_be32(hdr->ident); 260 261 hdr->nops_p = p; 262 *p = cpu_to_be32(hdr->nops); /* argarray element count */ 263 } 264 265 /* 266 * Update argarray element count 267 */ 268 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr) 269 { 270 BUG_ON(hdr->nops > NFS4_MAX_BACK_CHANNEL_OPS); 271 *hdr->nops_p = cpu_to_be32(hdr->nops); 272 } 273 274 /* 275 * CB_COMPOUND4res 276 * 277 * struct CB_COMPOUND4res { 278 * nfsstat4 status; 279 * utf8str_cs tag; 280 * nfs_cb_resop4 resarray<>; 281 * }; 282 */ 283 static int decode_cb_compound4res(struct xdr_stream *xdr, 284 struct nfs4_cb_compound_hdr *hdr) 285 { 286 u32 length; 287 __be32 *p; 288 289 p = xdr_inline_decode(xdr, 4 + 4); 290 if (unlikely(p == NULL)) 291 goto out_overflow; 292 hdr->status = be32_to_cpup(p++); 293 /* Ignore the tag */ 294 length = be32_to_cpup(p++); 295 p = xdr_inline_decode(xdr, length + 4); 296 if (unlikely(p == NULL)) 297 goto out_overflow; 298 p += XDR_QUADLEN(length); 299 hdr->nops = be32_to_cpup(p); 300 return 0; 301 out_overflow: 302 return -EIO; 303 } 304 305 /* 306 * CB_RECALL4args 307 * 308 * struct CB_RECALL4args { 309 * stateid4 stateid; 310 * bool truncate; 311 * nfs_fh4 fh; 312 * }; 313 */ 314 static void encode_cb_recall4args(struct xdr_stream *xdr, 315 const struct nfs4_delegation *dp, 316 struct nfs4_cb_compound_hdr *hdr) 317 { 318 __be32 *p; 319 320 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL); 321 encode_stateid4(xdr, &dp->dl_stid.sc_stateid); 322 323 p = xdr_reserve_space(xdr, 4); 324 *p++ = xdr_zero; /* truncate */ 325 326 encode_nfs_fh4(xdr, &dp->dl_stid.sc_file->fi_fhandle); 327 328 hdr->nops++; 329 } 330 331 /* 332 * CB_SEQUENCE4args 333 * 334 * struct CB_SEQUENCE4args { 335 * sessionid4 csa_sessionid; 336 * sequenceid4 csa_sequenceid; 337 * slotid4 csa_slotid; 338 * slotid4 csa_highest_slotid; 339 * bool csa_cachethis; 340 * referring_call_list4 csa_referring_call_lists<>; 341 * }; 342 */ 343 static void encode_cb_sequence4args(struct xdr_stream *xdr, 344 const struct nfsd4_callback *cb, 345 struct nfs4_cb_compound_hdr *hdr) 346 { 347 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 348 __be32 *p; 349 350 if (hdr->minorversion == 0) 351 return; 352 353 encode_nfs_cb_opnum4(xdr, OP_CB_SEQUENCE); 354 encode_sessionid4(xdr, session); 355 356 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4 + 4); 357 *p++ = cpu_to_be32(session->se_cb_seq_nr); /* csa_sequenceid */ 358 *p++ = xdr_zero; /* csa_slotid */ 359 *p++ = xdr_zero; /* csa_highest_slotid */ 360 *p++ = xdr_zero; /* csa_cachethis */ 361 xdr_encode_empty_array(p); /* csa_referring_call_lists */ 362 363 hdr->nops++; 364 } 365 366 /* 367 * CB_SEQUENCE4resok 368 * 369 * struct CB_SEQUENCE4resok { 370 * sessionid4 csr_sessionid; 371 * sequenceid4 csr_sequenceid; 372 * slotid4 csr_slotid; 373 * slotid4 csr_highest_slotid; 374 * slotid4 csr_target_highest_slotid; 375 * }; 376 * 377 * union CB_SEQUENCE4res switch (nfsstat4 csr_status) { 378 * case NFS4_OK: 379 * CB_SEQUENCE4resok csr_resok4; 380 * default: 381 * void; 382 * }; 383 * 384 * Our current back channel implmentation supports a single backchannel 385 * with a single slot. 386 */ 387 static int decode_cb_sequence4resok(struct xdr_stream *xdr, 388 struct nfsd4_callback *cb) 389 { 390 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 391 int status = -ESERVERFAULT; 392 __be32 *p; 393 u32 dummy; 394 395 /* 396 * If the server returns different values for sessionID, slotID or 397 * sequence number, the server is looney tunes. 398 */ 399 p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4); 400 if (unlikely(p == NULL)) 401 goto out_overflow; 402 403 if (memcmp(p, session->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) { 404 dprintk("NFS: %s Invalid session id\n", __func__); 405 goto out; 406 } 407 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN); 408 409 dummy = be32_to_cpup(p++); 410 if (dummy != session->se_cb_seq_nr) { 411 dprintk("NFS: %s Invalid sequence number\n", __func__); 412 goto out; 413 } 414 415 dummy = be32_to_cpup(p++); 416 if (dummy != 0) { 417 dprintk("NFS: %s Invalid slotid\n", __func__); 418 goto out; 419 } 420 421 /* 422 * FIXME: process highest slotid and target highest slotid 423 */ 424 status = 0; 425 out: 426 cb->cb_seq_status = status; 427 return status; 428 out_overflow: 429 status = -EIO; 430 goto out; 431 } 432 433 static int decode_cb_sequence4res(struct xdr_stream *xdr, 434 struct nfsd4_callback *cb) 435 { 436 int status; 437 438 if (cb->cb_clp->cl_minorversion == 0) 439 return 0; 440 441 status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status); 442 if (unlikely(status || cb->cb_seq_status)) 443 return status; 444 445 return decode_cb_sequence4resok(xdr, cb); 446 } 447 448 /* 449 * NFSv4.0 and NFSv4.1 XDR encode functions 450 * 451 * NFSv4.0 callback argument types are defined in section 15 of RFC 452 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 453 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 454 * Protocol". 455 */ 456 457 /* 458 * NB: Without this zero space reservation, callbacks over krb5p fail 459 */ 460 static void nfs4_xdr_enc_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 461 const void *__unused) 462 { 463 xdr_reserve_space(xdr, 0); 464 } 465 466 /* 467 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 468 */ 469 static void nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, struct xdr_stream *xdr, 470 const void *data) 471 { 472 const struct nfsd4_callback *cb = data; 473 const struct nfs4_delegation *dp = cb_to_delegation(cb); 474 struct nfs4_cb_compound_hdr hdr = { 475 .ident = cb->cb_clp->cl_cb_ident, 476 .minorversion = cb->cb_clp->cl_minorversion, 477 }; 478 479 encode_cb_compound4args(xdr, &hdr); 480 encode_cb_sequence4args(xdr, cb, &hdr); 481 encode_cb_recall4args(xdr, dp, &hdr); 482 encode_cb_nops(&hdr); 483 } 484 485 486 /* 487 * NFSv4.0 and NFSv4.1 XDR decode functions 488 * 489 * NFSv4.0 callback result types are defined in section 15 of RFC 490 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 491 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 492 * Protocol". 493 */ 494 495 static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 496 void *__unused) 497 { 498 return 0; 499 } 500 501 /* 502 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 503 */ 504 static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, 505 struct xdr_stream *xdr, 506 void *data) 507 { 508 struct nfsd4_callback *cb = data; 509 struct nfs4_cb_compound_hdr hdr; 510 int status; 511 512 status = decode_cb_compound4res(xdr, &hdr); 513 if (unlikely(status)) 514 return status; 515 516 status = decode_cb_sequence4res(xdr, cb); 517 if (unlikely(status || cb->cb_seq_status)) 518 return status; 519 520 return decode_cb_op_status(xdr, OP_CB_RECALL, &cb->cb_status); 521 } 522 523 #ifdef CONFIG_NFSD_PNFS 524 /* 525 * CB_LAYOUTRECALL4args 526 * 527 * struct layoutrecall_file4 { 528 * nfs_fh4 lor_fh; 529 * offset4 lor_offset; 530 * length4 lor_length; 531 * stateid4 lor_stateid; 532 * }; 533 * 534 * union layoutrecall4 switch(layoutrecall_type4 lor_recalltype) { 535 * case LAYOUTRECALL4_FILE: 536 * layoutrecall_file4 lor_layout; 537 * case LAYOUTRECALL4_FSID: 538 * fsid4 lor_fsid; 539 * case LAYOUTRECALL4_ALL: 540 * void; 541 * }; 542 * 543 * struct CB_LAYOUTRECALL4args { 544 * layouttype4 clora_type; 545 * layoutiomode4 clora_iomode; 546 * bool clora_changed; 547 * layoutrecall4 clora_recall; 548 * }; 549 */ 550 static void encode_cb_layout4args(struct xdr_stream *xdr, 551 const struct nfs4_layout_stateid *ls, 552 struct nfs4_cb_compound_hdr *hdr) 553 { 554 __be32 *p; 555 556 BUG_ON(hdr->minorversion == 0); 557 558 p = xdr_reserve_space(xdr, 5 * 4); 559 *p++ = cpu_to_be32(OP_CB_LAYOUTRECALL); 560 *p++ = cpu_to_be32(ls->ls_layout_type); 561 *p++ = cpu_to_be32(IOMODE_ANY); 562 *p++ = cpu_to_be32(1); 563 *p = cpu_to_be32(RETURN_FILE); 564 565 encode_nfs_fh4(xdr, &ls->ls_stid.sc_file->fi_fhandle); 566 567 p = xdr_reserve_space(xdr, 2 * 8); 568 p = xdr_encode_hyper(p, 0); 569 xdr_encode_hyper(p, NFS4_MAX_UINT64); 570 571 encode_stateid4(xdr, &ls->ls_recall_sid); 572 573 hdr->nops++; 574 } 575 576 static void nfs4_xdr_enc_cb_layout(struct rpc_rqst *req, 577 struct xdr_stream *xdr, 578 const void *data) 579 { 580 const struct nfsd4_callback *cb = data; 581 const struct nfs4_layout_stateid *ls = 582 container_of(cb, struct nfs4_layout_stateid, ls_recall); 583 struct nfs4_cb_compound_hdr hdr = { 584 .ident = 0, 585 .minorversion = cb->cb_clp->cl_minorversion, 586 }; 587 588 encode_cb_compound4args(xdr, &hdr); 589 encode_cb_sequence4args(xdr, cb, &hdr); 590 encode_cb_layout4args(xdr, ls, &hdr); 591 encode_cb_nops(&hdr); 592 } 593 594 static int nfs4_xdr_dec_cb_layout(struct rpc_rqst *rqstp, 595 struct xdr_stream *xdr, 596 void *data) 597 { 598 struct nfsd4_callback *cb = data; 599 struct nfs4_cb_compound_hdr hdr; 600 int status; 601 602 status = decode_cb_compound4res(xdr, &hdr); 603 if (unlikely(status)) 604 return status; 605 606 status = decode_cb_sequence4res(xdr, cb); 607 if (unlikely(status || cb->cb_seq_status)) 608 return status; 609 610 return decode_cb_op_status(xdr, OP_CB_LAYOUTRECALL, &cb->cb_status); 611 } 612 #endif /* CONFIG_NFSD_PNFS */ 613 614 static void encode_stateowner(struct xdr_stream *xdr, struct nfs4_stateowner *so) 615 { 616 __be32 *p; 617 618 p = xdr_reserve_space(xdr, 8 + 4 + so->so_owner.len); 619 p = xdr_encode_opaque_fixed(p, &so->so_client->cl_clientid, 8); 620 xdr_encode_opaque(p, so->so_owner.data, so->so_owner.len); 621 } 622 623 static void nfs4_xdr_enc_cb_notify_lock(struct rpc_rqst *req, 624 struct xdr_stream *xdr, 625 const void *data) 626 { 627 const struct nfsd4_callback *cb = data; 628 const struct nfsd4_blocked_lock *nbl = 629 container_of(cb, struct nfsd4_blocked_lock, nbl_cb); 630 struct nfs4_lockowner *lo = (struct nfs4_lockowner *)nbl->nbl_lock.fl_owner; 631 struct nfs4_cb_compound_hdr hdr = { 632 .ident = 0, 633 .minorversion = cb->cb_clp->cl_minorversion, 634 }; 635 636 __be32 *p; 637 638 BUG_ON(hdr.minorversion == 0); 639 640 encode_cb_compound4args(xdr, &hdr); 641 encode_cb_sequence4args(xdr, cb, &hdr); 642 643 p = xdr_reserve_space(xdr, 4); 644 *p = cpu_to_be32(OP_CB_NOTIFY_LOCK); 645 encode_nfs_fh4(xdr, &nbl->nbl_fh); 646 encode_stateowner(xdr, &lo->lo_owner); 647 hdr.nops++; 648 649 encode_cb_nops(&hdr); 650 } 651 652 static int nfs4_xdr_dec_cb_notify_lock(struct rpc_rqst *rqstp, 653 struct xdr_stream *xdr, 654 void *data) 655 { 656 struct nfsd4_callback *cb = data; 657 struct nfs4_cb_compound_hdr hdr; 658 int status; 659 660 status = decode_cb_compound4res(xdr, &hdr); 661 if (unlikely(status)) 662 return status; 663 664 status = decode_cb_sequence4res(xdr, cb); 665 if (unlikely(status || cb->cb_seq_status)) 666 return status; 667 668 return decode_cb_op_status(xdr, OP_CB_NOTIFY_LOCK, &cb->cb_status); 669 } 670 671 /* 672 * struct write_response4 { 673 * stateid4 wr_callback_id<1>; 674 * length4 wr_count; 675 * stable_how4 wr_committed; 676 * verifier4 wr_writeverf; 677 * }; 678 * union offload_info4 switch (nfsstat4 coa_status) { 679 * case NFS4_OK: 680 * write_response4 coa_resok4; 681 * default: 682 * length4 coa_bytes_copied; 683 * }; 684 * struct CB_OFFLOAD4args { 685 * nfs_fh4 coa_fh; 686 * stateid4 coa_stateid; 687 * offload_info4 coa_offload_info; 688 * }; 689 */ 690 static void encode_offload_info4(struct xdr_stream *xdr, 691 __be32 nfserr, 692 const struct nfsd4_copy *cp) 693 { 694 __be32 *p; 695 696 p = xdr_reserve_space(xdr, 4); 697 *p++ = nfserr; 698 if (!nfserr) { 699 p = xdr_reserve_space(xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE); 700 p = xdr_encode_empty_array(p); 701 p = xdr_encode_hyper(p, cp->cp_res.wr_bytes_written); 702 *p++ = cpu_to_be32(cp->cp_res.wr_stable_how); 703 p = xdr_encode_opaque_fixed(p, cp->cp_res.wr_verifier.data, 704 NFS4_VERIFIER_SIZE); 705 } else { 706 p = xdr_reserve_space(xdr, 8); 707 /* We always return success if bytes were written */ 708 p = xdr_encode_hyper(p, 0); 709 } 710 } 711 712 static void encode_cb_offload4args(struct xdr_stream *xdr, 713 __be32 nfserr, 714 const struct knfsd_fh *fh, 715 const struct nfsd4_copy *cp, 716 struct nfs4_cb_compound_hdr *hdr) 717 { 718 __be32 *p; 719 720 p = xdr_reserve_space(xdr, 4); 721 *p++ = cpu_to_be32(OP_CB_OFFLOAD); 722 encode_nfs_fh4(xdr, fh); 723 encode_stateid4(xdr, &cp->cp_res.cb_stateid); 724 encode_offload_info4(xdr, nfserr, cp); 725 726 hdr->nops++; 727 } 728 729 static void nfs4_xdr_enc_cb_offload(struct rpc_rqst *req, 730 struct xdr_stream *xdr, 731 const void *data) 732 { 733 const struct nfsd4_callback *cb = data; 734 const struct nfsd4_copy *cp = 735 container_of(cb, struct nfsd4_copy, cp_cb); 736 struct nfs4_cb_compound_hdr hdr = { 737 .ident = 0, 738 .minorversion = cb->cb_clp->cl_minorversion, 739 }; 740 741 encode_cb_compound4args(xdr, &hdr); 742 encode_cb_sequence4args(xdr, cb, &hdr); 743 encode_cb_offload4args(xdr, cp->nfserr, &cp->fh, cp, &hdr); 744 encode_cb_nops(&hdr); 745 } 746 747 static int nfs4_xdr_dec_cb_offload(struct rpc_rqst *rqstp, 748 struct xdr_stream *xdr, 749 void *data) 750 { 751 struct nfsd4_callback *cb = data; 752 struct nfs4_cb_compound_hdr hdr; 753 int status; 754 755 status = decode_cb_compound4res(xdr, &hdr); 756 if (unlikely(status)) 757 return status; 758 759 status = decode_cb_sequence4res(xdr, cb); 760 if (unlikely(status || cb->cb_seq_status)) 761 return status; 762 763 return decode_cb_op_status(xdr, OP_CB_OFFLOAD, &cb->cb_status); 764 } 765 /* 766 * RPC procedure tables 767 */ 768 #define PROC(proc, call, argtype, restype) \ 769 [NFSPROC4_CLNT_##proc] = { \ 770 .p_proc = NFSPROC4_CB_##call, \ 771 .p_encode = nfs4_xdr_enc_##argtype, \ 772 .p_decode = nfs4_xdr_dec_##restype, \ 773 .p_arglen = NFS4_enc_##argtype##_sz, \ 774 .p_replen = NFS4_dec_##restype##_sz, \ 775 .p_statidx = NFSPROC4_CB_##call, \ 776 .p_name = #proc, \ 777 } 778 779 static const struct rpc_procinfo nfs4_cb_procedures[] = { 780 PROC(CB_NULL, NULL, cb_null, cb_null), 781 PROC(CB_RECALL, COMPOUND, cb_recall, cb_recall), 782 #ifdef CONFIG_NFSD_PNFS 783 PROC(CB_LAYOUT, COMPOUND, cb_layout, cb_layout), 784 #endif 785 PROC(CB_NOTIFY_LOCK, COMPOUND, cb_notify_lock, cb_notify_lock), 786 PROC(CB_OFFLOAD, COMPOUND, cb_offload, cb_offload), 787 }; 788 789 static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)]; 790 static const struct rpc_version nfs_cb_version4 = { 791 /* 792 * Note on the callback rpc program version number: despite language in rfc 793 * 5661 section 18.36.3 requiring servers to use 4 in this field, the 794 * official xdr descriptions for both 4.0 and 4.1 specify version 1, and 795 * in practice that appears to be what implementations use. The section 796 * 18.36.3 language is expected to be fixed in an erratum. 797 */ 798 .number = 1, 799 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 800 .procs = nfs4_cb_procedures, 801 .counts = nfs4_cb_counts, 802 }; 803 804 static const struct rpc_version *nfs_cb_version[2] = { 805 [1] = &nfs_cb_version4, 806 }; 807 808 static const struct rpc_program cb_program; 809 810 static struct rpc_stat cb_stats = { 811 .program = &cb_program 812 }; 813 814 #define NFS4_CALLBACK 0x40000000 815 static const struct rpc_program cb_program = { 816 .name = "nfs4_cb", 817 .number = NFS4_CALLBACK, 818 .nrvers = ARRAY_SIZE(nfs_cb_version), 819 .version = nfs_cb_version, 820 .stats = &cb_stats, 821 .pipe_dir_name = "nfsd4_cb", 822 }; 823 824 static int max_cb_time(struct net *net) 825 { 826 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 827 828 /* 829 * nfsd4_lease is set to at most one hour in __nfsd4_write_time, 830 * so we can use 32-bit math on it. Warn if that assumption 831 * ever stops being true. 832 */ 833 if (WARN_ON_ONCE(nn->nfsd4_lease > 3600)) 834 return 360 * HZ; 835 836 return max(((u32)nn->nfsd4_lease)/10, 1u) * HZ; 837 } 838 839 static struct workqueue_struct *callback_wq; 840 841 static bool nfsd4_queue_cb(struct nfsd4_callback *cb) 842 { 843 return queue_work(callback_wq, &cb->cb_work); 844 } 845 846 static void nfsd41_cb_inflight_begin(struct nfs4_client *clp) 847 { 848 atomic_inc(&clp->cl_cb_inflight); 849 } 850 851 static void nfsd41_cb_inflight_end(struct nfs4_client *clp) 852 { 853 854 if (atomic_dec_and_test(&clp->cl_cb_inflight)) 855 wake_up_var(&clp->cl_cb_inflight); 856 } 857 858 static void nfsd41_cb_inflight_wait_complete(struct nfs4_client *clp) 859 { 860 wait_var_event(&clp->cl_cb_inflight, 861 !atomic_read(&clp->cl_cb_inflight)); 862 } 863 864 static const struct cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc_clnt *client, struct nfsd4_session *ses) 865 { 866 if (clp->cl_minorversion == 0) { 867 client->cl_principal = clp->cl_cred.cr_targ_princ ? 868 clp->cl_cred.cr_targ_princ : "nfs"; 869 870 return get_cred(rpc_machine_cred()); 871 } else { 872 struct cred *kcred; 873 874 kcred = prepare_kernel_cred(NULL); 875 if (!kcred) 876 return NULL; 877 878 kcred->uid = ses->se_cb_sec.uid; 879 kcred->gid = ses->se_cb_sec.gid; 880 return kcred; 881 } 882 } 883 884 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses) 885 { 886 int maxtime = max_cb_time(clp->net); 887 struct rpc_timeout timeparms = { 888 .to_initval = maxtime, 889 .to_retries = 0, 890 .to_maxval = maxtime, 891 }; 892 struct rpc_create_args args = { 893 .net = clp->net, 894 .address = (struct sockaddr *) &conn->cb_addr, 895 .addrsize = conn->cb_addrlen, 896 .saddress = (struct sockaddr *) &conn->cb_saddr, 897 .timeout = &timeparms, 898 .program = &cb_program, 899 .version = 1, 900 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), 901 .cred = current_cred(), 902 }; 903 struct rpc_clnt *client; 904 const struct cred *cred; 905 906 if (clp->cl_minorversion == 0) { 907 if (!clp->cl_cred.cr_principal && 908 (clp->cl_cred.cr_flavor >= RPC_AUTH_GSS_KRB5)) { 909 trace_nfsd_cb_setup_err(clp, -EINVAL); 910 return -EINVAL; 911 } 912 args.client_name = clp->cl_cred.cr_principal; 913 args.prognumber = conn->cb_prog; 914 args.protocol = XPRT_TRANSPORT_TCP; 915 args.authflavor = clp->cl_cred.cr_flavor; 916 clp->cl_cb_ident = conn->cb_ident; 917 } else { 918 if (!conn->cb_xprt) 919 return -EINVAL; 920 clp->cl_cb_conn.cb_xprt = conn->cb_xprt; 921 clp->cl_cb_session = ses; 922 args.bc_xprt = conn->cb_xprt; 923 args.prognumber = clp->cl_cb_session->se_cb_prog; 924 args.protocol = conn->cb_xprt->xpt_class->xcl_ident | 925 XPRT_TRANSPORT_BC; 926 args.authflavor = ses->se_cb_sec.flavor; 927 } 928 /* Create RPC client */ 929 client = rpc_create(&args); 930 if (IS_ERR(client)) { 931 trace_nfsd_cb_setup_err(clp, PTR_ERR(client)); 932 return PTR_ERR(client); 933 } 934 cred = get_backchannel_cred(clp, client, ses); 935 if (!cred) { 936 trace_nfsd_cb_setup_err(clp, -ENOMEM); 937 rpc_shutdown_client(client); 938 return -ENOMEM; 939 } 940 clp->cl_cb_client = client; 941 clp->cl_cb_cred = cred; 942 rcu_read_lock(); 943 trace_nfsd_cb_setup(clp, rpc_peeraddr2str(client, RPC_DISPLAY_NETID), 944 args.authflavor); 945 rcu_read_unlock(); 946 return 0; 947 } 948 949 static void nfsd4_mark_cb_state(struct nfs4_client *clp, int newstate) 950 { 951 if (clp->cl_cb_state != newstate) { 952 clp->cl_cb_state = newstate; 953 trace_nfsd_cb_state(clp); 954 } 955 } 956 957 static void nfsd4_mark_cb_down(struct nfs4_client *clp, int reason) 958 { 959 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 960 return; 961 nfsd4_mark_cb_state(clp, NFSD4_CB_DOWN); 962 } 963 964 static void nfsd4_mark_cb_fault(struct nfs4_client *clp, int reason) 965 { 966 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 967 return; 968 nfsd4_mark_cb_state(clp, NFSD4_CB_FAULT); 969 } 970 971 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata) 972 { 973 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 974 975 if (task->tk_status) 976 nfsd4_mark_cb_down(clp, task->tk_status); 977 else 978 nfsd4_mark_cb_state(clp, NFSD4_CB_UP); 979 } 980 981 static void nfsd4_cb_probe_release(void *calldata) 982 { 983 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 984 985 nfsd41_cb_inflight_end(clp); 986 987 } 988 989 static const struct rpc_call_ops nfsd4_cb_probe_ops = { 990 /* XXX: release method to ensure we set the cb channel down if 991 * necessary on early failure? */ 992 .rpc_call_done = nfsd4_cb_probe_done, 993 .rpc_release = nfsd4_cb_probe_release, 994 }; 995 996 /* 997 * Poke the callback thread to process any updates to the callback 998 * parameters, and send a null probe. 999 */ 1000 void nfsd4_probe_callback(struct nfs4_client *clp) 1001 { 1002 trace_nfsd_cb_probe(clp); 1003 nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN); 1004 set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1005 nfsd4_run_cb(&clp->cl_cb_null); 1006 } 1007 1008 void nfsd4_probe_callback_sync(struct nfs4_client *clp) 1009 { 1010 nfsd4_probe_callback(clp); 1011 flush_workqueue(callback_wq); 1012 } 1013 1014 void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn) 1015 { 1016 nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN); 1017 spin_lock(&clp->cl_lock); 1018 memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn)); 1019 spin_unlock(&clp->cl_lock); 1020 } 1021 1022 /* 1023 * There's currently a single callback channel slot. 1024 * If the slot is available, then mark it busy. Otherwise, set the 1025 * thread for sleeping on the callback RPC wait queue. 1026 */ 1027 static bool nfsd41_cb_get_slot(struct nfsd4_callback *cb, struct rpc_task *task) 1028 { 1029 struct nfs4_client *clp = cb->cb_clp; 1030 1031 if (!cb->cb_holds_slot && 1032 test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 1033 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL); 1034 /* Race breaker */ 1035 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 1036 dprintk("%s slot is busy\n", __func__); 1037 return false; 1038 } 1039 rpc_wake_up_queued_task(&clp->cl_cb_waitq, task); 1040 } 1041 cb->cb_holds_slot = true; 1042 return true; 1043 } 1044 1045 static void nfsd41_cb_release_slot(struct nfsd4_callback *cb) 1046 { 1047 struct nfs4_client *clp = cb->cb_clp; 1048 1049 if (cb->cb_holds_slot) { 1050 cb->cb_holds_slot = false; 1051 clear_bit(0, &clp->cl_cb_slot_busy); 1052 rpc_wake_up_next(&clp->cl_cb_waitq); 1053 } 1054 } 1055 1056 static void nfsd41_destroy_cb(struct nfsd4_callback *cb) 1057 { 1058 struct nfs4_client *clp = cb->cb_clp; 1059 1060 nfsd41_cb_release_slot(cb); 1061 if (cb->cb_ops && cb->cb_ops->release) 1062 cb->cb_ops->release(cb); 1063 nfsd41_cb_inflight_end(clp); 1064 } 1065 1066 /* 1067 * TODO: cb_sequence should support referring call lists, cachethis, multiple 1068 * slots, and mark callback channel down on communication errors. 1069 */ 1070 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata) 1071 { 1072 struct nfsd4_callback *cb = calldata; 1073 struct nfs4_client *clp = cb->cb_clp; 1074 u32 minorversion = clp->cl_minorversion; 1075 1076 /* 1077 * cb_seq_status is only set in decode_cb_sequence4res, 1078 * and so will remain 1 if an rpc level failure occurs. 1079 */ 1080 cb->cb_seq_status = 1; 1081 cb->cb_status = 0; 1082 if (minorversion && !nfsd41_cb_get_slot(cb, task)) 1083 return; 1084 rpc_call_start(task); 1085 } 1086 1087 static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback *cb) 1088 { 1089 struct nfs4_client *clp = cb->cb_clp; 1090 struct nfsd4_session *session = clp->cl_cb_session; 1091 bool ret = true; 1092 1093 if (!clp->cl_minorversion) { 1094 /* 1095 * If the backchannel connection was shut down while this 1096 * task was queued, we need to resubmit it after setting up 1097 * a new backchannel connection. 1098 * 1099 * Note that if we lost our callback connection permanently 1100 * the submission code will error out, so we don't need to 1101 * handle that case here. 1102 */ 1103 if (RPC_SIGNALLED(task)) 1104 goto need_restart; 1105 1106 return true; 1107 } 1108 1109 if (!cb->cb_holds_slot) 1110 goto need_restart; 1111 1112 switch (cb->cb_seq_status) { 1113 case 0: 1114 /* 1115 * No need for lock, access serialized in nfsd4_cb_prepare 1116 * 1117 * RFC5661 20.9.3 1118 * If CB_SEQUENCE returns an error, then the state of the slot 1119 * (sequence ID, cached reply) MUST NOT change. 1120 */ 1121 ++session->se_cb_seq_nr; 1122 break; 1123 case -ESERVERFAULT: 1124 ++session->se_cb_seq_nr; 1125 fallthrough; 1126 case 1: 1127 case -NFS4ERR_BADSESSION: 1128 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 1129 ret = false; 1130 break; 1131 case -NFS4ERR_DELAY: 1132 if (!rpc_restart_call(task)) 1133 goto out; 1134 1135 rpc_delay(task, 2 * HZ); 1136 return false; 1137 case -NFS4ERR_BADSLOT: 1138 goto retry_nowait; 1139 case -NFS4ERR_SEQ_MISORDERED: 1140 if (session->se_cb_seq_nr != 1) { 1141 session->se_cb_seq_nr = 1; 1142 goto retry_nowait; 1143 } 1144 break; 1145 default: 1146 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 1147 dprintk("%s: unprocessed error %d\n", __func__, 1148 cb->cb_seq_status); 1149 } 1150 1151 nfsd41_cb_release_slot(cb); 1152 dprintk("%s: freed slot, new seqid=%d\n", __func__, 1153 clp->cl_cb_session->se_cb_seq_nr); 1154 1155 if (RPC_SIGNALLED(task)) 1156 goto need_restart; 1157 out: 1158 return ret; 1159 retry_nowait: 1160 if (rpc_restart_call_prepare(task)) 1161 ret = false; 1162 goto out; 1163 need_restart: 1164 if (!test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) { 1165 task->tk_status = 0; 1166 cb->cb_need_restart = true; 1167 } 1168 return false; 1169 } 1170 1171 static void nfsd4_cb_done(struct rpc_task *task, void *calldata) 1172 { 1173 struct nfsd4_callback *cb = calldata; 1174 struct nfs4_client *clp = cb->cb_clp; 1175 1176 if (!nfsd4_cb_sequence_done(task, cb)) 1177 return; 1178 1179 if (cb->cb_status) { 1180 WARN_ON_ONCE(task->tk_status); 1181 task->tk_status = cb->cb_status; 1182 } 1183 1184 switch (cb->cb_ops->done(cb, task)) { 1185 case 0: 1186 task->tk_status = 0; 1187 rpc_restart_call_prepare(task); 1188 return; 1189 case 1: 1190 switch (task->tk_status) { 1191 case -EIO: 1192 case -ETIMEDOUT: 1193 case -EACCES: 1194 nfsd4_mark_cb_down(clp, task->tk_status); 1195 } 1196 break; 1197 default: 1198 BUG(); 1199 } 1200 } 1201 1202 static void nfsd4_cb_release(void *calldata) 1203 { 1204 struct nfsd4_callback *cb = calldata; 1205 1206 if (cb->cb_need_restart) 1207 nfsd4_queue_cb(cb); 1208 else 1209 nfsd41_destroy_cb(cb); 1210 1211 } 1212 1213 static const struct rpc_call_ops nfsd4_cb_ops = { 1214 .rpc_call_prepare = nfsd4_cb_prepare, 1215 .rpc_call_done = nfsd4_cb_done, 1216 .rpc_release = nfsd4_cb_release, 1217 }; 1218 1219 int nfsd4_create_callback_queue(void) 1220 { 1221 callback_wq = alloc_ordered_workqueue("nfsd4_callbacks", 0); 1222 if (!callback_wq) 1223 return -ENOMEM; 1224 return 0; 1225 } 1226 1227 void nfsd4_destroy_callback_queue(void) 1228 { 1229 destroy_workqueue(callback_wq); 1230 } 1231 1232 /* must be called under the state lock */ 1233 void nfsd4_shutdown_callback(struct nfs4_client *clp) 1234 { 1235 if (clp->cl_cb_state != NFSD4_CB_UNKNOWN) 1236 trace_nfsd_cb_shutdown(clp); 1237 1238 set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); 1239 /* 1240 * Note this won't actually result in a null callback; 1241 * instead, nfsd4_run_cb_null() will detect the killed 1242 * client, destroy the rpc client, and stop: 1243 */ 1244 nfsd4_run_cb(&clp->cl_cb_null); 1245 flush_workqueue(callback_wq); 1246 nfsd41_cb_inflight_wait_complete(clp); 1247 } 1248 1249 /* requires cl_lock: */ 1250 static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp) 1251 { 1252 struct nfsd4_session *s; 1253 struct nfsd4_conn *c; 1254 1255 list_for_each_entry(s, &clp->cl_sessions, se_perclnt) { 1256 list_for_each_entry(c, &s->se_conns, cn_persession) { 1257 if (c->cn_flags & NFS4_CDFC4_BACK) 1258 return c; 1259 } 1260 } 1261 return NULL; 1262 } 1263 1264 /* 1265 * Note there isn't a lot of locking in this code; instead we depend on 1266 * the fact that it is run from the callback_wq, which won't run two 1267 * work items at once. So, for example, callback_wq handles all access 1268 * of cl_cb_client and all calls to rpc_create or rpc_shutdown_client. 1269 */ 1270 static void nfsd4_process_cb_update(struct nfsd4_callback *cb) 1271 { 1272 struct nfs4_cb_conn conn; 1273 struct nfs4_client *clp = cb->cb_clp; 1274 struct nfsd4_session *ses = NULL; 1275 struct nfsd4_conn *c; 1276 int err; 1277 1278 /* 1279 * This is either an update, or the client dying; in either case, 1280 * kill the old client: 1281 */ 1282 if (clp->cl_cb_client) { 1283 rpc_shutdown_client(clp->cl_cb_client); 1284 clp->cl_cb_client = NULL; 1285 put_cred(clp->cl_cb_cred); 1286 clp->cl_cb_cred = NULL; 1287 } 1288 if (clp->cl_cb_conn.cb_xprt) { 1289 svc_xprt_put(clp->cl_cb_conn.cb_xprt); 1290 clp->cl_cb_conn.cb_xprt = NULL; 1291 } 1292 if (test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) 1293 return; 1294 spin_lock(&clp->cl_lock); 1295 /* 1296 * Only serialized callback code is allowed to clear these 1297 * flags; main nfsd code can only set them: 1298 */ 1299 BUG_ON(!(clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK)); 1300 clear_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1301 memcpy(&conn, &cb->cb_clp->cl_cb_conn, sizeof(struct nfs4_cb_conn)); 1302 c = __nfsd4_find_backchannel(clp); 1303 if (c) { 1304 svc_xprt_get(c->cn_xprt); 1305 conn.cb_xprt = c->cn_xprt; 1306 ses = c->cn_session; 1307 } 1308 spin_unlock(&clp->cl_lock); 1309 1310 err = setup_callback_client(clp, &conn, ses); 1311 if (err) { 1312 nfsd4_mark_cb_down(clp, err); 1313 if (c) 1314 svc_xprt_put(c->cn_xprt); 1315 return; 1316 } 1317 } 1318 1319 static void 1320 nfsd4_run_cb_work(struct work_struct *work) 1321 { 1322 struct nfsd4_callback *cb = 1323 container_of(work, struct nfsd4_callback, cb_work); 1324 struct nfs4_client *clp = cb->cb_clp; 1325 struct rpc_clnt *clnt; 1326 int flags; 1327 1328 if (cb->cb_need_restart) { 1329 cb->cb_need_restart = false; 1330 } else { 1331 if (cb->cb_ops && cb->cb_ops->prepare) 1332 cb->cb_ops->prepare(cb); 1333 } 1334 1335 if (clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK) 1336 nfsd4_process_cb_update(cb); 1337 1338 clnt = clp->cl_cb_client; 1339 if (!clnt) { 1340 /* Callback channel broken, or client killed; give up: */ 1341 nfsd41_destroy_cb(cb); 1342 return; 1343 } 1344 1345 /* 1346 * Don't send probe messages for 4.1 or later. 1347 */ 1348 if (!cb->cb_ops && clp->cl_minorversion) { 1349 nfsd4_mark_cb_state(clp, NFSD4_CB_UP); 1350 nfsd41_destroy_cb(cb); 1351 return; 1352 } 1353 1354 cb->cb_msg.rpc_cred = clp->cl_cb_cred; 1355 flags = clp->cl_minorversion ? RPC_TASK_NOCONNECT : RPC_TASK_SOFTCONN; 1356 rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | flags, 1357 cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb); 1358 } 1359 1360 void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, 1361 const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op) 1362 { 1363 cb->cb_clp = clp; 1364 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[op]; 1365 cb->cb_msg.rpc_argp = cb; 1366 cb->cb_msg.rpc_resp = cb; 1367 cb->cb_ops = ops; 1368 INIT_WORK(&cb->cb_work, nfsd4_run_cb_work); 1369 cb->cb_seq_status = 1; 1370 cb->cb_status = 0; 1371 cb->cb_need_restart = false; 1372 cb->cb_holds_slot = false; 1373 } 1374 1375 void nfsd4_run_cb(struct nfsd4_callback *cb) 1376 { 1377 struct nfs4_client *clp = cb->cb_clp; 1378 1379 nfsd41_cb_inflight_begin(clp); 1380 if (!nfsd4_queue_cb(cb)) 1381 nfsd41_cb_inflight_end(clp); 1382 } 1383