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/nfs4.h> 35 #include <linux/sunrpc/clnt.h> 36 #include <linux/sunrpc/xprt.h> 37 #include <linux/sunrpc/svc_xprt.h> 38 #include <linux/slab.h> 39 #include "nfsd.h" 40 #include "state.h" 41 #include "netns.h" 42 #include "trace.h" 43 #include "xdr4cb.h" 44 #include "xdr4.h" 45 46 #define NFSDDBG_FACILITY NFSDDBG_PROC 47 48 static void nfsd4_mark_cb_fault(struct nfs4_client *, int reason); 49 50 #define NFSPROC4_CB_NULL 0 51 #define NFSPROC4_CB_COMPOUND 1 52 53 /* Index of predefined Linux callback client operations */ 54 55 struct nfs4_cb_compound_hdr { 56 /* args */ 57 u32 ident; /* minorversion 0 only */ 58 u32 nops; 59 __be32 *nops_p; 60 u32 minorversion; 61 /* res */ 62 int status; 63 }; 64 65 static __be32 *xdr_encode_empty_array(__be32 *p) 66 { 67 *p++ = xdr_zero; 68 return p; 69 } 70 71 /* 72 * Encode/decode NFSv4 CB basic data types 73 * 74 * Basic NFSv4 callback data types are defined in section 15 of RFC 75 * 3530: "Network File System (NFS) version 4 Protocol" and section 76 * 20 of RFC 5661: "Network File System (NFS) Version 4 Minor Version 77 * 1 Protocol" 78 */ 79 80 static void encode_uint32(struct xdr_stream *xdr, u32 n) 81 { 82 WARN_ON_ONCE(xdr_stream_encode_u32(xdr, n) < 0); 83 } 84 85 static void encode_bitmap4(struct xdr_stream *xdr, const __u32 *bitmap, 86 size_t len) 87 { 88 WARN_ON_ONCE(xdr_stream_encode_uint32_array(xdr, bitmap, len) < 0); 89 } 90 91 static void encode_nfs_cb_opnum4(struct xdr_stream *xdr, enum nfs_cb_opnum4 op) 92 { 93 __be32 *p; 94 95 p = xdr_reserve_space(xdr, 4); 96 *p = cpu_to_be32(op); 97 } 98 99 /* 100 * nfs_fh4 101 * 102 * typedef opaque nfs_fh4<NFS4_FHSIZE>; 103 */ 104 static void encode_nfs_fh4(struct xdr_stream *xdr, const struct knfsd_fh *fh) 105 { 106 u32 length = fh->fh_size; 107 __be32 *p; 108 109 BUG_ON(length > NFS4_FHSIZE); 110 p = xdr_reserve_space(xdr, 4 + length); 111 xdr_encode_opaque(p, &fh->fh_raw, length); 112 } 113 114 /* 115 * stateid4 116 * 117 * struct stateid4 { 118 * uint32_t seqid; 119 * opaque other[12]; 120 * }; 121 */ 122 static void encode_stateid4(struct xdr_stream *xdr, const stateid_t *sid) 123 { 124 __be32 *p; 125 126 p = xdr_reserve_space(xdr, NFS4_STATEID_SIZE); 127 *p++ = cpu_to_be32(sid->si_generation); 128 xdr_encode_opaque_fixed(p, &sid->si_opaque, NFS4_STATEID_OTHER_SIZE); 129 } 130 131 /* 132 * sessionid4 133 * 134 * typedef opaque sessionid4[NFS4_SESSIONID_SIZE]; 135 */ 136 static void encode_sessionid4(struct xdr_stream *xdr, 137 const struct nfsd4_session *session) 138 { 139 __be32 *p; 140 141 p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN); 142 xdr_encode_opaque_fixed(p, session->se_sessionid.data, 143 NFS4_MAX_SESSIONID_LEN); 144 } 145 146 /* 147 * nfsstat4 148 */ 149 static const struct { 150 int stat; 151 int errno; 152 } nfs_cb_errtbl[] = { 153 { NFS4_OK, 0 }, 154 { NFS4ERR_PERM, -EPERM }, 155 { NFS4ERR_NOENT, -ENOENT }, 156 { NFS4ERR_IO, -EIO }, 157 { NFS4ERR_NXIO, -ENXIO }, 158 { NFS4ERR_ACCESS, -EACCES }, 159 { NFS4ERR_EXIST, -EEXIST }, 160 { NFS4ERR_XDEV, -EXDEV }, 161 { NFS4ERR_NOTDIR, -ENOTDIR }, 162 { NFS4ERR_ISDIR, -EISDIR }, 163 { NFS4ERR_INVAL, -EINVAL }, 164 { NFS4ERR_FBIG, -EFBIG }, 165 { NFS4ERR_NOSPC, -ENOSPC }, 166 { NFS4ERR_ROFS, -EROFS }, 167 { NFS4ERR_MLINK, -EMLINK }, 168 { NFS4ERR_NAMETOOLONG, -ENAMETOOLONG }, 169 { NFS4ERR_NOTEMPTY, -ENOTEMPTY }, 170 { NFS4ERR_DQUOT, -EDQUOT }, 171 { NFS4ERR_STALE, -ESTALE }, 172 { NFS4ERR_BADHANDLE, -EBADHANDLE }, 173 { NFS4ERR_BAD_COOKIE, -EBADCOOKIE }, 174 { NFS4ERR_NOTSUPP, -ENOTSUPP }, 175 { NFS4ERR_TOOSMALL, -ETOOSMALL }, 176 { NFS4ERR_SERVERFAULT, -ESERVERFAULT }, 177 { NFS4ERR_BADTYPE, -EBADTYPE }, 178 { NFS4ERR_LOCKED, -EAGAIN }, 179 { NFS4ERR_RESOURCE, -EREMOTEIO }, 180 { NFS4ERR_SYMLINK, -ELOOP }, 181 { NFS4ERR_OP_ILLEGAL, -EOPNOTSUPP }, 182 { NFS4ERR_DEADLOCK, -EDEADLK }, 183 { -1, -EIO } 184 }; 185 186 /* 187 * If we cannot translate the error, the recovery routines should 188 * handle it. 189 * 190 * Note: remaining NFSv4 error codes have values > 10000, so should 191 * not conflict with native Linux error codes. 192 */ 193 static int nfs_cb_stat_to_errno(int status) 194 { 195 int i; 196 197 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 198 if (nfs_cb_errtbl[i].stat == status) 199 return nfs_cb_errtbl[i].errno; 200 } 201 202 dprintk("NFSD: Unrecognized NFS CB status value: %u\n", status); 203 return -status; 204 } 205 206 static int decode_cb_op_status(struct xdr_stream *xdr, 207 enum nfs_cb_opnum4 expected, int *status) 208 { 209 __be32 *p; 210 u32 op; 211 212 p = xdr_inline_decode(xdr, 4 + 4); 213 if (unlikely(p == NULL)) 214 goto out_overflow; 215 op = be32_to_cpup(p++); 216 if (unlikely(op != expected)) 217 goto out_unexpected; 218 *status = nfs_cb_stat_to_errno(be32_to_cpup(p)); 219 return 0; 220 out_overflow: 221 return -EIO; 222 out_unexpected: 223 dprintk("NFSD: Callback server returned operation %d but " 224 "we issued a request for %d\n", op, expected); 225 return -EIO; 226 } 227 228 /* 229 * CB_COMPOUND4args 230 * 231 * struct CB_COMPOUND4args { 232 * utf8str_cs tag; 233 * uint32_t minorversion; 234 * uint32_t callback_ident; 235 * nfs_cb_argop4 argarray<>; 236 * }; 237 */ 238 static void encode_cb_compound4args(struct xdr_stream *xdr, 239 struct nfs4_cb_compound_hdr *hdr) 240 { 241 __be32 * p; 242 243 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 244 p = xdr_encode_empty_array(p); /* empty tag */ 245 *p++ = cpu_to_be32(hdr->minorversion); 246 *p++ = cpu_to_be32(hdr->ident); 247 248 hdr->nops_p = p; 249 *p = cpu_to_be32(hdr->nops); /* argarray element count */ 250 } 251 252 /* 253 * Update argarray element count 254 */ 255 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr) 256 { 257 BUG_ON(hdr->nops > NFS4_MAX_BACK_CHANNEL_OPS); 258 *hdr->nops_p = cpu_to_be32(hdr->nops); 259 } 260 261 /* 262 * CB_COMPOUND4res 263 * 264 * struct CB_COMPOUND4res { 265 * nfsstat4 status; 266 * utf8str_cs tag; 267 * nfs_cb_resop4 resarray<>; 268 * }; 269 */ 270 static int decode_cb_compound4res(struct xdr_stream *xdr, 271 struct nfs4_cb_compound_hdr *hdr) 272 { 273 u32 length; 274 __be32 *p; 275 276 p = xdr_inline_decode(xdr, 4 + 4); 277 if (unlikely(p == NULL)) 278 goto out_overflow; 279 hdr->status = be32_to_cpup(p++); 280 /* Ignore the tag */ 281 length = be32_to_cpup(p++); 282 p = xdr_inline_decode(xdr, length + 4); 283 if (unlikely(p == NULL)) 284 goto out_overflow; 285 p += XDR_QUADLEN(length); 286 hdr->nops = be32_to_cpup(p); 287 return 0; 288 out_overflow: 289 return -EIO; 290 } 291 292 /* 293 * CB_RECALL4args 294 * 295 * struct CB_RECALL4args { 296 * stateid4 stateid; 297 * bool truncate; 298 * nfs_fh4 fh; 299 * }; 300 */ 301 static void encode_cb_recall4args(struct xdr_stream *xdr, 302 const struct nfs4_delegation *dp, 303 struct nfs4_cb_compound_hdr *hdr) 304 { 305 __be32 *p; 306 307 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL); 308 encode_stateid4(xdr, &dp->dl_stid.sc_stateid); 309 310 p = xdr_reserve_space(xdr, 4); 311 *p++ = xdr_zero; /* truncate */ 312 313 encode_nfs_fh4(xdr, &dp->dl_stid.sc_file->fi_fhandle); 314 315 hdr->nops++; 316 } 317 318 /* 319 * CB_RECALLANY4args 320 * 321 * struct CB_RECALLANY4args { 322 * uint32_t craa_objects_to_keep; 323 * bitmap4 craa_type_mask; 324 * }; 325 */ 326 static void 327 encode_cb_recallany4args(struct xdr_stream *xdr, 328 struct nfs4_cb_compound_hdr *hdr, struct nfsd4_cb_recall_any *ra) 329 { 330 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL_ANY); 331 encode_uint32(xdr, ra->ra_keep); 332 encode_bitmap4(xdr, ra->ra_bmval, ARRAY_SIZE(ra->ra_bmval)); 333 hdr->nops++; 334 } 335 336 /* 337 * CB_SEQUENCE4args 338 * 339 * struct CB_SEQUENCE4args { 340 * sessionid4 csa_sessionid; 341 * sequenceid4 csa_sequenceid; 342 * slotid4 csa_slotid; 343 * slotid4 csa_highest_slotid; 344 * bool csa_cachethis; 345 * referring_call_list4 csa_referring_call_lists<>; 346 * }; 347 */ 348 static void encode_cb_sequence4args(struct xdr_stream *xdr, 349 const struct nfsd4_callback *cb, 350 struct nfs4_cb_compound_hdr *hdr) 351 { 352 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 353 __be32 *p; 354 355 if (hdr->minorversion == 0) 356 return; 357 358 encode_nfs_cb_opnum4(xdr, OP_CB_SEQUENCE); 359 encode_sessionid4(xdr, session); 360 361 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4 + 4); 362 *p++ = cpu_to_be32(session->se_cb_seq_nr); /* csa_sequenceid */ 363 *p++ = xdr_zero; /* csa_slotid */ 364 *p++ = xdr_zero; /* csa_highest_slotid */ 365 *p++ = xdr_zero; /* csa_cachethis */ 366 xdr_encode_empty_array(p); /* csa_referring_call_lists */ 367 368 hdr->nops++; 369 } 370 371 /* 372 * CB_SEQUENCE4resok 373 * 374 * struct CB_SEQUENCE4resok { 375 * sessionid4 csr_sessionid; 376 * sequenceid4 csr_sequenceid; 377 * slotid4 csr_slotid; 378 * slotid4 csr_highest_slotid; 379 * slotid4 csr_target_highest_slotid; 380 * }; 381 * 382 * union CB_SEQUENCE4res switch (nfsstat4 csr_status) { 383 * case NFS4_OK: 384 * CB_SEQUENCE4resok csr_resok4; 385 * default: 386 * void; 387 * }; 388 * 389 * Our current back channel implmentation supports a single backchannel 390 * with a single slot. 391 */ 392 static int decode_cb_sequence4resok(struct xdr_stream *xdr, 393 struct nfsd4_callback *cb) 394 { 395 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 396 int status = -ESERVERFAULT; 397 __be32 *p; 398 u32 dummy; 399 400 /* 401 * If the server returns different values for sessionID, slotID or 402 * sequence number, the server is looney tunes. 403 */ 404 p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4); 405 if (unlikely(p == NULL)) 406 goto out_overflow; 407 408 if (memcmp(p, session->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) { 409 dprintk("NFS: %s Invalid session id\n", __func__); 410 goto out; 411 } 412 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN); 413 414 dummy = be32_to_cpup(p++); 415 if (dummy != session->se_cb_seq_nr) { 416 dprintk("NFS: %s Invalid sequence number\n", __func__); 417 goto out; 418 } 419 420 dummy = be32_to_cpup(p++); 421 if (dummy != 0) { 422 dprintk("NFS: %s Invalid slotid\n", __func__); 423 goto out; 424 } 425 426 /* 427 * FIXME: process highest slotid and target highest slotid 428 */ 429 status = 0; 430 out: 431 cb->cb_seq_status = status; 432 return status; 433 out_overflow: 434 status = -EIO; 435 goto out; 436 } 437 438 static int decode_cb_sequence4res(struct xdr_stream *xdr, 439 struct nfsd4_callback *cb) 440 { 441 int status; 442 443 if (cb->cb_clp->cl_minorversion == 0) 444 return 0; 445 446 status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status); 447 if (unlikely(status || cb->cb_seq_status)) 448 return status; 449 450 return decode_cb_sequence4resok(xdr, cb); 451 } 452 453 /* 454 * NFSv4.0 and NFSv4.1 XDR encode functions 455 * 456 * NFSv4.0 callback argument types are defined in section 15 of RFC 457 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 458 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 459 * Protocol". 460 */ 461 462 /* 463 * NB: Without this zero space reservation, callbacks over krb5p fail 464 */ 465 static void nfs4_xdr_enc_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 466 const void *__unused) 467 { 468 xdr_reserve_space(xdr, 0); 469 } 470 471 /* 472 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 473 */ 474 static void nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, struct xdr_stream *xdr, 475 const void *data) 476 { 477 const struct nfsd4_callback *cb = data; 478 const struct nfs4_delegation *dp = cb_to_delegation(cb); 479 struct nfs4_cb_compound_hdr hdr = { 480 .ident = cb->cb_clp->cl_cb_ident, 481 .minorversion = cb->cb_clp->cl_minorversion, 482 }; 483 484 encode_cb_compound4args(xdr, &hdr); 485 encode_cb_sequence4args(xdr, cb, &hdr); 486 encode_cb_recall4args(xdr, dp, &hdr); 487 encode_cb_nops(&hdr); 488 } 489 490 /* 491 * 20.6. Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects 492 */ 493 static void 494 nfs4_xdr_enc_cb_recall_any(struct rpc_rqst *req, 495 struct xdr_stream *xdr, const void *data) 496 { 497 const struct nfsd4_callback *cb = data; 498 struct nfsd4_cb_recall_any *ra; 499 struct nfs4_cb_compound_hdr hdr = { 500 .ident = cb->cb_clp->cl_cb_ident, 501 .minorversion = cb->cb_clp->cl_minorversion, 502 }; 503 504 ra = container_of(cb, struct nfsd4_cb_recall_any, ra_cb); 505 encode_cb_compound4args(xdr, &hdr); 506 encode_cb_sequence4args(xdr, cb, &hdr); 507 encode_cb_recallany4args(xdr, &hdr, ra); 508 encode_cb_nops(&hdr); 509 } 510 511 /* 512 * NFSv4.0 and NFSv4.1 XDR decode functions 513 * 514 * NFSv4.0 callback result types are defined in section 15 of RFC 515 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 516 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 517 * Protocol". 518 */ 519 520 static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 521 void *__unused) 522 { 523 return 0; 524 } 525 526 /* 527 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 528 */ 529 static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, 530 struct xdr_stream *xdr, 531 void *data) 532 { 533 struct nfsd4_callback *cb = data; 534 struct nfs4_cb_compound_hdr hdr; 535 int status; 536 537 status = decode_cb_compound4res(xdr, &hdr); 538 if (unlikely(status)) 539 return status; 540 541 status = decode_cb_sequence4res(xdr, cb); 542 if (unlikely(status || cb->cb_seq_status)) 543 return status; 544 545 return decode_cb_op_status(xdr, OP_CB_RECALL, &cb->cb_status); 546 } 547 548 /* 549 * 20.6. Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects 550 */ 551 static int 552 nfs4_xdr_dec_cb_recall_any(struct rpc_rqst *rqstp, 553 struct xdr_stream *xdr, 554 void *data) 555 { 556 struct nfsd4_callback *cb = data; 557 struct nfs4_cb_compound_hdr hdr; 558 int status; 559 560 status = decode_cb_compound4res(xdr, &hdr); 561 if (unlikely(status)) 562 return status; 563 status = decode_cb_sequence4res(xdr, cb); 564 if (unlikely(status || cb->cb_seq_status)) 565 return status; 566 status = decode_cb_op_status(xdr, OP_CB_RECALL_ANY, &cb->cb_status); 567 return status; 568 } 569 570 #ifdef CONFIG_NFSD_PNFS 571 /* 572 * CB_LAYOUTRECALL4args 573 * 574 * struct layoutrecall_file4 { 575 * nfs_fh4 lor_fh; 576 * offset4 lor_offset; 577 * length4 lor_length; 578 * stateid4 lor_stateid; 579 * }; 580 * 581 * union layoutrecall4 switch(layoutrecall_type4 lor_recalltype) { 582 * case LAYOUTRECALL4_FILE: 583 * layoutrecall_file4 lor_layout; 584 * case LAYOUTRECALL4_FSID: 585 * fsid4 lor_fsid; 586 * case LAYOUTRECALL4_ALL: 587 * void; 588 * }; 589 * 590 * struct CB_LAYOUTRECALL4args { 591 * layouttype4 clora_type; 592 * layoutiomode4 clora_iomode; 593 * bool clora_changed; 594 * layoutrecall4 clora_recall; 595 * }; 596 */ 597 static void encode_cb_layout4args(struct xdr_stream *xdr, 598 const struct nfs4_layout_stateid *ls, 599 struct nfs4_cb_compound_hdr *hdr) 600 { 601 __be32 *p; 602 603 BUG_ON(hdr->minorversion == 0); 604 605 p = xdr_reserve_space(xdr, 5 * 4); 606 *p++ = cpu_to_be32(OP_CB_LAYOUTRECALL); 607 *p++ = cpu_to_be32(ls->ls_layout_type); 608 *p++ = cpu_to_be32(IOMODE_ANY); 609 *p++ = cpu_to_be32(1); 610 *p = cpu_to_be32(RETURN_FILE); 611 612 encode_nfs_fh4(xdr, &ls->ls_stid.sc_file->fi_fhandle); 613 614 p = xdr_reserve_space(xdr, 2 * 8); 615 p = xdr_encode_hyper(p, 0); 616 xdr_encode_hyper(p, NFS4_MAX_UINT64); 617 618 encode_stateid4(xdr, &ls->ls_recall_sid); 619 620 hdr->nops++; 621 } 622 623 static void nfs4_xdr_enc_cb_layout(struct rpc_rqst *req, 624 struct xdr_stream *xdr, 625 const void *data) 626 { 627 const struct nfsd4_callback *cb = data; 628 const struct nfs4_layout_stateid *ls = 629 container_of(cb, struct nfs4_layout_stateid, ls_recall); 630 struct nfs4_cb_compound_hdr hdr = { 631 .ident = 0, 632 .minorversion = cb->cb_clp->cl_minorversion, 633 }; 634 635 encode_cb_compound4args(xdr, &hdr); 636 encode_cb_sequence4args(xdr, cb, &hdr); 637 encode_cb_layout4args(xdr, ls, &hdr); 638 encode_cb_nops(&hdr); 639 } 640 641 static int nfs4_xdr_dec_cb_layout(struct rpc_rqst *rqstp, 642 struct xdr_stream *xdr, 643 void *data) 644 { 645 struct nfsd4_callback *cb = data; 646 struct nfs4_cb_compound_hdr hdr; 647 int status; 648 649 status = decode_cb_compound4res(xdr, &hdr); 650 if (unlikely(status)) 651 return status; 652 653 status = decode_cb_sequence4res(xdr, cb); 654 if (unlikely(status || cb->cb_seq_status)) 655 return status; 656 657 return decode_cb_op_status(xdr, OP_CB_LAYOUTRECALL, &cb->cb_status); 658 } 659 #endif /* CONFIG_NFSD_PNFS */ 660 661 static void encode_stateowner(struct xdr_stream *xdr, struct nfs4_stateowner *so) 662 { 663 __be32 *p; 664 665 p = xdr_reserve_space(xdr, 8 + 4 + so->so_owner.len); 666 p = xdr_encode_opaque_fixed(p, &so->so_client->cl_clientid, 8); 667 xdr_encode_opaque(p, so->so_owner.data, so->so_owner.len); 668 } 669 670 static void nfs4_xdr_enc_cb_notify_lock(struct rpc_rqst *req, 671 struct xdr_stream *xdr, 672 const void *data) 673 { 674 const struct nfsd4_callback *cb = data; 675 const struct nfsd4_blocked_lock *nbl = 676 container_of(cb, struct nfsd4_blocked_lock, nbl_cb); 677 struct nfs4_lockowner *lo = (struct nfs4_lockowner *)nbl->nbl_lock.fl_owner; 678 struct nfs4_cb_compound_hdr hdr = { 679 .ident = 0, 680 .minorversion = cb->cb_clp->cl_minorversion, 681 }; 682 683 __be32 *p; 684 685 BUG_ON(hdr.minorversion == 0); 686 687 encode_cb_compound4args(xdr, &hdr); 688 encode_cb_sequence4args(xdr, cb, &hdr); 689 690 p = xdr_reserve_space(xdr, 4); 691 *p = cpu_to_be32(OP_CB_NOTIFY_LOCK); 692 encode_nfs_fh4(xdr, &nbl->nbl_fh); 693 encode_stateowner(xdr, &lo->lo_owner); 694 hdr.nops++; 695 696 encode_cb_nops(&hdr); 697 } 698 699 static int nfs4_xdr_dec_cb_notify_lock(struct rpc_rqst *rqstp, 700 struct xdr_stream *xdr, 701 void *data) 702 { 703 struct nfsd4_callback *cb = data; 704 struct nfs4_cb_compound_hdr hdr; 705 int status; 706 707 status = decode_cb_compound4res(xdr, &hdr); 708 if (unlikely(status)) 709 return status; 710 711 status = decode_cb_sequence4res(xdr, cb); 712 if (unlikely(status || cb->cb_seq_status)) 713 return status; 714 715 return decode_cb_op_status(xdr, OP_CB_NOTIFY_LOCK, &cb->cb_status); 716 } 717 718 /* 719 * struct write_response4 { 720 * stateid4 wr_callback_id<1>; 721 * length4 wr_count; 722 * stable_how4 wr_committed; 723 * verifier4 wr_writeverf; 724 * }; 725 * union offload_info4 switch (nfsstat4 coa_status) { 726 * case NFS4_OK: 727 * write_response4 coa_resok4; 728 * default: 729 * length4 coa_bytes_copied; 730 * }; 731 * struct CB_OFFLOAD4args { 732 * nfs_fh4 coa_fh; 733 * stateid4 coa_stateid; 734 * offload_info4 coa_offload_info; 735 * }; 736 */ 737 static void encode_offload_info4(struct xdr_stream *xdr, 738 const struct nfsd4_cb_offload *cbo) 739 { 740 __be32 *p; 741 742 p = xdr_reserve_space(xdr, 4); 743 *p = cbo->co_nfserr; 744 switch (cbo->co_nfserr) { 745 case nfs_ok: 746 p = xdr_reserve_space(xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE); 747 p = xdr_encode_empty_array(p); 748 p = xdr_encode_hyper(p, cbo->co_res.wr_bytes_written); 749 *p++ = cpu_to_be32(cbo->co_res.wr_stable_how); 750 p = xdr_encode_opaque_fixed(p, cbo->co_res.wr_verifier.data, 751 NFS4_VERIFIER_SIZE); 752 break; 753 default: 754 p = xdr_reserve_space(xdr, 8); 755 /* We always return success if bytes were written */ 756 p = xdr_encode_hyper(p, 0); 757 } 758 } 759 760 static void encode_cb_offload4args(struct xdr_stream *xdr, 761 const struct nfsd4_cb_offload *cbo, 762 struct nfs4_cb_compound_hdr *hdr) 763 { 764 __be32 *p; 765 766 p = xdr_reserve_space(xdr, 4); 767 *p = cpu_to_be32(OP_CB_OFFLOAD); 768 encode_nfs_fh4(xdr, &cbo->co_fh); 769 encode_stateid4(xdr, &cbo->co_res.cb_stateid); 770 encode_offload_info4(xdr, cbo); 771 772 hdr->nops++; 773 } 774 775 static void nfs4_xdr_enc_cb_offload(struct rpc_rqst *req, 776 struct xdr_stream *xdr, 777 const void *data) 778 { 779 const struct nfsd4_callback *cb = data; 780 const struct nfsd4_cb_offload *cbo = 781 container_of(cb, struct nfsd4_cb_offload, co_cb); 782 struct nfs4_cb_compound_hdr hdr = { 783 .ident = 0, 784 .minorversion = cb->cb_clp->cl_minorversion, 785 }; 786 787 encode_cb_compound4args(xdr, &hdr); 788 encode_cb_sequence4args(xdr, cb, &hdr); 789 encode_cb_offload4args(xdr, cbo, &hdr); 790 encode_cb_nops(&hdr); 791 } 792 793 static int nfs4_xdr_dec_cb_offload(struct rpc_rqst *rqstp, 794 struct xdr_stream *xdr, 795 void *data) 796 { 797 struct nfsd4_callback *cb = data; 798 struct nfs4_cb_compound_hdr hdr; 799 int status; 800 801 status = decode_cb_compound4res(xdr, &hdr); 802 if (unlikely(status)) 803 return status; 804 805 status = decode_cb_sequence4res(xdr, cb); 806 if (unlikely(status || cb->cb_seq_status)) 807 return status; 808 809 return decode_cb_op_status(xdr, OP_CB_OFFLOAD, &cb->cb_status); 810 } 811 /* 812 * RPC procedure tables 813 */ 814 #define PROC(proc, call, argtype, restype) \ 815 [NFSPROC4_CLNT_##proc] = { \ 816 .p_proc = NFSPROC4_CB_##call, \ 817 .p_encode = nfs4_xdr_enc_##argtype, \ 818 .p_decode = nfs4_xdr_dec_##restype, \ 819 .p_arglen = NFS4_enc_##argtype##_sz, \ 820 .p_replen = NFS4_dec_##restype##_sz, \ 821 .p_statidx = NFSPROC4_CB_##call, \ 822 .p_name = #proc, \ 823 } 824 825 static const struct rpc_procinfo nfs4_cb_procedures[] = { 826 PROC(CB_NULL, NULL, cb_null, cb_null), 827 PROC(CB_RECALL, COMPOUND, cb_recall, cb_recall), 828 #ifdef CONFIG_NFSD_PNFS 829 PROC(CB_LAYOUT, COMPOUND, cb_layout, cb_layout), 830 #endif 831 PROC(CB_NOTIFY_LOCK, COMPOUND, cb_notify_lock, cb_notify_lock), 832 PROC(CB_OFFLOAD, COMPOUND, cb_offload, cb_offload), 833 PROC(CB_RECALL_ANY, COMPOUND, cb_recall_any, cb_recall_any), 834 }; 835 836 static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)]; 837 static const struct rpc_version nfs_cb_version4 = { 838 /* 839 * Note on the callback rpc program version number: despite language in rfc 840 * 5661 section 18.36.3 requiring servers to use 4 in this field, the 841 * official xdr descriptions for both 4.0 and 4.1 specify version 1, and 842 * in practice that appears to be what implementations use. The section 843 * 18.36.3 language is expected to be fixed in an erratum. 844 */ 845 .number = 1, 846 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 847 .procs = nfs4_cb_procedures, 848 .counts = nfs4_cb_counts, 849 }; 850 851 static const struct rpc_version *nfs_cb_version[2] = { 852 [1] = &nfs_cb_version4, 853 }; 854 855 static const struct rpc_program cb_program; 856 857 static struct rpc_stat cb_stats = { 858 .program = &cb_program 859 }; 860 861 #define NFS4_CALLBACK 0x40000000 862 static const struct rpc_program cb_program = { 863 .name = "nfs4_cb", 864 .number = NFS4_CALLBACK, 865 .nrvers = ARRAY_SIZE(nfs_cb_version), 866 .version = nfs_cb_version, 867 .stats = &cb_stats, 868 .pipe_dir_name = "nfsd4_cb", 869 }; 870 871 static int max_cb_time(struct net *net) 872 { 873 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 874 875 /* 876 * nfsd4_lease is set to at most one hour in __nfsd4_write_time, 877 * so we can use 32-bit math on it. Warn if that assumption 878 * ever stops being true. 879 */ 880 if (WARN_ON_ONCE(nn->nfsd4_lease > 3600)) 881 return 360 * HZ; 882 883 return max(((u32)nn->nfsd4_lease)/10, 1u) * HZ; 884 } 885 886 static struct workqueue_struct *callback_wq; 887 888 static bool nfsd4_queue_cb(struct nfsd4_callback *cb) 889 { 890 return queue_work(callback_wq, &cb->cb_work); 891 } 892 893 static void nfsd41_cb_inflight_begin(struct nfs4_client *clp) 894 { 895 atomic_inc(&clp->cl_cb_inflight); 896 } 897 898 static void nfsd41_cb_inflight_end(struct nfs4_client *clp) 899 { 900 901 if (atomic_dec_and_test(&clp->cl_cb_inflight)) 902 wake_up_var(&clp->cl_cb_inflight); 903 } 904 905 static void nfsd41_cb_inflight_wait_complete(struct nfs4_client *clp) 906 { 907 wait_var_event(&clp->cl_cb_inflight, 908 !atomic_read(&clp->cl_cb_inflight)); 909 } 910 911 static const struct cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc_clnt *client, struct nfsd4_session *ses) 912 { 913 if (clp->cl_minorversion == 0) { 914 client->cl_principal = clp->cl_cred.cr_targ_princ ? 915 clp->cl_cred.cr_targ_princ : "nfs"; 916 917 return get_cred(rpc_machine_cred()); 918 } else { 919 struct cred *kcred; 920 921 kcred = prepare_kernel_cred(&init_task); 922 if (!kcred) 923 return NULL; 924 925 kcred->fsuid = ses->se_cb_sec.uid; 926 kcred->fsgid = ses->se_cb_sec.gid; 927 return kcred; 928 } 929 } 930 931 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses) 932 { 933 int maxtime = max_cb_time(clp->net); 934 struct rpc_timeout timeparms = { 935 .to_initval = maxtime, 936 .to_retries = 0, 937 .to_maxval = maxtime, 938 }; 939 struct rpc_create_args args = { 940 .net = clp->net, 941 .address = (struct sockaddr *) &conn->cb_addr, 942 .addrsize = conn->cb_addrlen, 943 .saddress = (struct sockaddr *) &conn->cb_saddr, 944 .timeout = &timeparms, 945 .program = &cb_program, 946 .version = 1, 947 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), 948 .cred = current_cred(), 949 }; 950 struct rpc_clnt *client; 951 const struct cred *cred; 952 953 if (clp->cl_minorversion == 0) { 954 if (!clp->cl_cred.cr_principal && 955 (clp->cl_cred.cr_flavor >= RPC_AUTH_GSS_KRB5)) { 956 trace_nfsd_cb_setup_err(clp, -EINVAL); 957 return -EINVAL; 958 } 959 args.client_name = clp->cl_cred.cr_principal; 960 args.prognumber = conn->cb_prog; 961 args.protocol = XPRT_TRANSPORT_TCP; 962 args.authflavor = clp->cl_cred.cr_flavor; 963 clp->cl_cb_ident = conn->cb_ident; 964 } else { 965 if (!conn->cb_xprt) 966 return -EINVAL; 967 clp->cl_cb_session = ses; 968 args.bc_xprt = conn->cb_xprt; 969 args.prognumber = clp->cl_cb_session->se_cb_prog; 970 args.protocol = conn->cb_xprt->xpt_class->xcl_ident | 971 XPRT_TRANSPORT_BC; 972 args.authflavor = ses->se_cb_sec.flavor; 973 } 974 /* Create RPC client */ 975 client = rpc_create(&args); 976 if (IS_ERR(client)) { 977 trace_nfsd_cb_setup_err(clp, PTR_ERR(client)); 978 return PTR_ERR(client); 979 } 980 cred = get_backchannel_cred(clp, client, ses); 981 if (!cred) { 982 trace_nfsd_cb_setup_err(clp, -ENOMEM); 983 rpc_shutdown_client(client); 984 return -ENOMEM; 985 } 986 987 if (clp->cl_minorversion != 0) 988 clp->cl_cb_conn.cb_xprt = conn->cb_xprt; 989 clp->cl_cb_client = client; 990 clp->cl_cb_cred = cred; 991 rcu_read_lock(); 992 trace_nfsd_cb_setup(clp, rpc_peeraddr2str(client, RPC_DISPLAY_NETID), 993 args.authflavor); 994 rcu_read_unlock(); 995 return 0; 996 } 997 998 static void nfsd4_mark_cb_state(struct nfs4_client *clp, int newstate) 999 { 1000 if (clp->cl_cb_state != newstate) { 1001 clp->cl_cb_state = newstate; 1002 trace_nfsd_cb_state(clp); 1003 } 1004 } 1005 1006 static void nfsd4_mark_cb_down(struct nfs4_client *clp, int reason) 1007 { 1008 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 1009 return; 1010 nfsd4_mark_cb_state(clp, NFSD4_CB_DOWN); 1011 } 1012 1013 static void nfsd4_mark_cb_fault(struct nfs4_client *clp, int reason) 1014 { 1015 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 1016 return; 1017 nfsd4_mark_cb_state(clp, NFSD4_CB_FAULT); 1018 } 1019 1020 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata) 1021 { 1022 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 1023 1024 if (task->tk_status) 1025 nfsd4_mark_cb_down(clp, task->tk_status); 1026 else 1027 nfsd4_mark_cb_state(clp, NFSD4_CB_UP); 1028 } 1029 1030 static void nfsd4_cb_probe_release(void *calldata) 1031 { 1032 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 1033 1034 nfsd41_cb_inflight_end(clp); 1035 1036 } 1037 1038 static const struct rpc_call_ops nfsd4_cb_probe_ops = { 1039 /* XXX: release method to ensure we set the cb channel down if 1040 * necessary on early failure? */ 1041 .rpc_call_done = nfsd4_cb_probe_done, 1042 .rpc_release = nfsd4_cb_probe_release, 1043 }; 1044 1045 /* 1046 * Poke the callback thread to process any updates to the callback 1047 * parameters, and send a null probe. 1048 */ 1049 void nfsd4_probe_callback(struct nfs4_client *clp) 1050 { 1051 trace_nfsd_cb_probe(clp); 1052 nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN); 1053 set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1054 nfsd4_run_cb(&clp->cl_cb_null); 1055 } 1056 1057 void nfsd4_probe_callback_sync(struct nfs4_client *clp) 1058 { 1059 nfsd4_probe_callback(clp); 1060 flush_workqueue(callback_wq); 1061 } 1062 1063 void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn) 1064 { 1065 nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN); 1066 spin_lock(&clp->cl_lock); 1067 memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn)); 1068 spin_unlock(&clp->cl_lock); 1069 } 1070 1071 /* 1072 * There's currently a single callback channel slot. 1073 * If the slot is available, then mark it busy. Otherwise, set the 1074 * thread for sleeping on the callback RPC wait queue. 1075 */ 1076 static bool nfsd41_cb_get_slot(struct nfsd4_callback *cb, struct rpc_task *task) 1077 { 1078 struct nfs4_client *clp = cb->cb_clp; 1079 1080 if (!cb->cb_holds_slot && 1081 test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 1082 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL); 1083 /* Race breaker */ 1084 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 1085 dprintk("%s slot is busy\n", __func__); 1086 return false; 1087 } 1088 rpc_wake_up_queued_task(&clp->cl_cb_waitq, task); 1089 } 1090 cb->cb_holds_slot = true; 1091 return true; 1092 } 1093 1094 static void nfsd41_cb_release_slot(struct nfsd4_callback *cb) 1095 { 1096 struct nfs4_client *clp = cb->cb_clp; 1097 1098 if (cb->cb_holds_slot) { 1099 cb->cb_holds_slot = false; 1100 clear_bit(0, &clp->cl_cb_slot_busy); 1101 rpc_wake_up_next(&clp->cl_cb_waitq); 1102 } 1103 } 1104 1105 static void nfsd41_destroy_cb(struct nfsd4_callback *cb) 1106 { 1107 struct nfs4_client *clp = cb->cb_clp; 1108 1109 nfsd41_cb_release_slot(cb); 1110 if (cb->cb_ops && cb->cb_ops->release) 1111 cb->cb_ops->release(cb); 1112 nfsd41_cb_inflight_end(clp); 1113 } 1114 1115 /* 1116 * TODO: cb_sequence should support referring call lists, cachethis, multiple 1117 * slots, and mark callback channel down on communication errors. 1118 */ 1119 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata) 1120 { 1121 struct nfsd4_callback *cb = calldata; 1122 struct nfs4_client *clp = cb->cb_clp; 1123 u32 minorversion = clp->cl_minorversion; 1124 1125 /* 1126 * cb_seq_status is only set in decode_cb_sequence4res, 1127 * and so will remain 1 if an rpc level failure occurs. 1128 */ 1129 cb->cb_seq_status = 1; 1130 cb->cb_status = 0; 1131 if (minorversion && !nfsd41_cb_get_slot(cb, task)) 1132 return; 1133 rpc_call_start(task); 1134 } 1135 1136 static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback *cb) 1137 { 1138 struct nfs4_client *clp = cb->cb_clp; 1139 struct nfsd4_session *session = clp->cl_cb_session; 1140 bool ret = true; 1141 1142 if (!clp->cl_minorversion) { 1143 /* 1144 * If the backchannel connection was shut down while this 1145 * task was queued, we need to resubmit it after setting up 1146 * a new backchannel connection. 1147 * 1148 * Note that if we lost our callback connection permanently 1149 * the submission code will error out, so we don't need to 1150 * handle that case here. 1151 */ 1152 if (RPC_SIGNALLED(task)) 1153 goto need_restart; 1154 1155 return true; 1156 } 1157 1158 if (!cb->cb_holds_slot) 1159 goto need_restart; 1160 1161 switch (cb->cb_seq_status) { 1162 case 0: 1163 /* 1164 * No need for lock, access serialized in nfsd4_cb_prepare 1165 * 1166 * RFC5661 20.9.3 1167 * If CB_SEQUENCE returns an error, then the state of the slot 1168 * (sequence ID, cached reply) MUST NOT change. 1169 */ 1170 ++session->se_cb_seq_nr; 1171 break; 1172 case -ESERVERFAULT: 1173 ++session->se_cb_seq_nr; 1174 fallthrough; 1175 case 1: 1176 case -NFS4ERR_BADSESSION: 1177 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 1178 ret = false; 1179 break; 1180 case -NFS4ERR_DELAY: 1181 if (!rpc_restart_call(task)) 1182 goto out; 1183 1184 rpc_delay(task, 2 * HZ); 1185 return false; 1186 case -NFS4ERR_BADSLOT: 1187 goto retry_nowait; 1188 case -NFS4ERR_SEQ_MISORDERED: 1189 if (session->se_cb_seq_nr != 1) { 1190 session->se_cb_seq_nr = 1; 1191 goto retry_nowait; 1192 } 1193 break; 1194 default: 1195 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 1196 dprintk("%s: unprocessed error %d\n", __func__, 1197 cb->cb_seq_status); 1198 } 1199 1200 nfsd41_cb_release_slot(cb); 1201 dprintk("%s: freed slot, new seqid=%d\n", __func__, 1202 clp->cl_cb_session->se_cb_seq_nr); 1203 1204 if (RPC_SIGNALLED(task)) 1205 goto need_restart; 1206 out: 1207 return ret; 1208 retry_nowait: 1209 if (rpc_restart_call_prepare(task)) 1210 ret = false; 1211 goto out; 1212 need_restart: 1213 if (!test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) { 1214 task->tk_status = 0; 1215 cb->cb_need_restart = true; 1216 } 1217 return false; 1218 } 1219 1220 static void nfsd4_cb_done(struct rpc_task *task, void *calldata) 1221 { 1222 struct nfsd4_callback *cb = calldata; 1223 struct nfs4_client *clp = cb->cb_clp; 1224 1225 if (!nfsd4_cb_sequence_done(task, cb)) 1226 return; 1227 1228 if (cb->cb_status) { 1229 WARN_ON_ONCE(task->tk_status); 1230 task->tk_status = cb->cb_status; 1231 } 1232 1233 switch (cb->cb_ops->done(cb, task)) { 1234 case 0: 1235 task->tk_status = 0; 1236 rpc_restart_call_prepare(task); 1237 return; 1238 case 1: 1239 switch (task->tk_status) { 1240 case -EIO: 1241 case -ETIMEDOUT: 1242 case -EACCES: 1243 nfsd4_mark_cb_down(clp, task->tk_status); 1244 } 1245 break; 1246 default: 1247 BUG(); 1248 } 1249 } 1250 1251 static void nfsd4_cb_release(void *calldata) 1252 { 1253 struct nfsd4_callback *cb = calldata; 1254 1255 if (cb->cb_need_restart) 1256 nfsd4_queue_cb(cb); 1257 else 1258 nfsd41_destroy_cb(cb); 1259 1260 } 1261 1262 static const struct rpc_call_ops nfsd4_cb_ops = { 1263 .rpc_call_prepare = nfsd4_cb_prepare, 1264 .rpc_call_done = nfsd4_cb_done, 1265 .rpc_release = nfsd4_cb_release, 1266 }; 1267 1268 int nfsd4_create_callback_queue(void) 1269 { 1270 callback_wq = alloc_ordered_workqueue("nfsd4_callbacks", 0); 1271 if (!callback_wq) 1272 return -ENOMEM; 1273 return 0; 1274 } 1275 1276 void nfsd4_destroy_callback_queue(void) 1277 { 1278 destroy_workqueue(callback_wq); 1279 } 1280 1281 /* must be called under the state lock */ 1282 void nfsd4_shutdown_callback(struct nfs4_client *clp) 1283 { 1284 if (clp->cl_cb_state != NFSD4_CB_UNKNOWN) 1285 trace_nfsd_cb_shutdown(clp); 1286 1287 set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); 1288 /* 1289 * Note this won't actually result in a null callback; 1290 * instead, nfsd4_run_cb_null() will detect the killed 1291 * client, destroy the rpc client, and stop: 1292 */ 1293 nfsd4_run_cb(&clp->cl_cb_null); 1294 flush_workqueue(callback_wq); 1295 nfsd41_cb_inflight_wait_complete(clp); 1296 } 1297 1298 /* requires cl_lock: */ 1299 static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp) 1300 { 1301 struct nfsd4_session *s; 1302 struct nfsd4_conn *c; 1303 1304 list_for_each_entry(s, &clp->cl_sessions, se_perclnt) { 1305 list_for_each_entry(c, &s->se_conns, cn_persession) { 1306 if (c->cn_flags & NFS4_CDFC4_BACK) 1307 return c; 1308 } 1309 } 1310 return NULL; 1311 } 1312 1313 /* 1314 * Note there isn't a lot of locking in this code; instead we depend on 1315 * the fact that it is run from the callback_wq, which won't run two 1316 * work items at once. So, for example, callback_wq handles all access 1317 * of cl_cb_client and all calls to rpc_create or rpc_shutdown_client. 1318 */ 1319 static void nfsd4_process_cb_update(struct nfsd4_callback *cb) 1320 { 1321 struct nfs4_cb_conn conn; 1322 struct nfs4_client *clp = cb->cb_clp; 1323 struct nfsd4_session *ses = NULL; 1324 struct nfsd4_conn *c; 1325 int err; 1326 1327 /* 1328 * This is either an update, or the client dying; in either case, 1329 * kill the old client: 1330 */ 1331 if (clp->cl_cb_client) { 1332 rpc_shutdown_client(clp->cl_cb_client); 1333 clp->cl_cb_client = NULL; 1334 put_cred(clp->cl_cb_cred); 1335 clp->cl_cb_cred = NULL; 1336 } 1337 if (clp->cl_cb_conn.cb_xprt) { 1338 svc_xprt_put(clp->cl_cb_conn.cb_xprt); 1339 clp->cl_cb_conn.cb_xprt = NULL; 1340 } 1341 if (test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) 1342 return; 1343 spin_lock(&clp->cl_lock); 1344 /* 1345 * Only serialized callback code is allowed to clear these 1346 * flags; main nfsd code can only set them: 1347 */ 1348 BUG_ON(!(clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK)); 1349 clear_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1350 memcpy(&conn, &cb->cb_clp->cl_cb_conn, sizeof(struct nfs4_cb_conn)); 1351 c = __nfsd4_find_backchannel(clp); 1352 if (c) { 1353 svc_xprt_get(c->cn_xprt); 1354 conn.cb_xprt = c->cn_xprt; 1355 ses = c->cn_session; 1356 } 1357 spin_unlock(&clp->cl_lock); 1358 1359 err = setup_callback_client(clp, &conn, ses); 1360 if (err) { 1361 nfsd4_mark_cb_down(clp, err); 1362 if (c) 1363 svc_xprt_put(c->cn_xprt); 1364 return; 1365 } 1366 } 1367 1368 static void 1369 nfsd4_run_cb_work(struct work_struct *work) 1370 { 1371 struct nfsd4_callback *cb = 1372 container_of(work, struct nfsd4_callback, cb_work); 1373 struct nfs4_client *clp = cb->cb_clp; 1374 struct rpc_clnt *clnt; 1375 int flags; 1376 1377 if (cb->cb_need_restart) { 1378 cb->cb_need_restart = false; 1379 } else { 1380 if (cb->cb_ops && cb->cb_ops->prepare) 1381 cb->cb_ops->prepare(cb); 1382 } 1383 1384 if (clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK) 1385 nfsd4_process_cb_update(cb); 1386 1387 clnt = clp->cl_cb_client; 1388 if (!clnt) { 1389 /* Callback channel broken, or client killed; give up: */ 1390 nfsd41_destroy_cb(cb); 1391 return; 1392 } 1393 1394 /* 1395 * Don't send probe messages for 4.1 or later. 1396 */ 1397 if (!cb->cb_ops && clp->cl_minorversion) { 1398 nfsd4_mark_cb_state(clp, NFSD4_CB_UP); 1399 nfsd41_destroy_cb(cb); 1400 return; 1401 } 1402 1403 cb->cb_msg.rpc_cred = clp->cl_cb_cred; 1404 flags = clp->cl_minorversion ? RPC_TASK_NOCONNECT : RPC_TASK_SOFTCONN; 1405 rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | flags, 1406 cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb); 1407 } 1408 1409 void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, 1410 const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op) 1411 { 1412 cb->cb_clp = clp; 1413 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[op]; 1414 cb->cb_msg.rpc_argp = cb; 1415 cb->cb_msg.rpc_resp = cb; 1416 cb->cb_ops = ops; 1417 INIT_WORK(&cb->cb_work, nfsd4_run_cb_work); 1418 cb->cb_seq_status = 1; 1419 cb->cb_status = 0; 1420 cb->cb_need_restart = false; 1421 cb->cb_holds_slot = false; 1422 } 1423 1424 /** 1425 * nfsd4_run_cb - queue up a callback job to run 1426 * @cb: callback to queue 1427 * 1428 * Kick off a callback to do its thing. Returns false if it was already 1429 * on a queue, true otherwise. 1430 */ 1431 bool nfsd4_run_cb(struct nfsd4_callback *cb) 1432 { 1433 struct nfs4_client *clp = cb->cb_clp; 1434 bool queued; 1435 1436 nfsd41_cb_inflight_begin(clp); 1437 queued = nfsd4_queue_cb(cb); 1438 if (!queued) 1439 nfsd41_cb_inflight_end(clp); 1440 return queued; 1441 } 1442