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 xdr_stream_encode_uint32_array(xdr, bitmap, len); 88 } 89 90 static int decode_cb_fattr4(struct xdr_stream *xdr, uint32_t *bitmap, 91 struct nfs4_cb_fattr *fattr) 92 { 93 fattr->ncf_cb_change = 0; 94 fattr->ncf_cb_fsize = 0; 95 if (bitmap[0] & FATTR4_WORD0_CHANGE) 96 if (xdr_stream_decode_u64(xdr, &fattr->ncf_cb_change) < 0) 97 return -NFSERR_BAD_XDR; 98 if (bitmap[0] & FATTR4_WORD0_SIZE) 99 if (xdr_stream_decode_u64(xdr, &fattr->ncf_cb_fsize) < 0) 100 return -NFSERR_BAD_XDR; 101 return 0; 102 } 103 104 /* 105 * nfs_cb_opnum4 106 * 107 * enum nfs_cb_opnum4 { 108 * OP_CB_GETATTR = 3, 109 * ... 110 * }; 111 */ 112 enum nfs_cb_opnum4 { 113 OP_CB_GETATTR = 3, 114 OP_CB_RECALL = 4, 115 OP_CB_LAYOUTRECALL = 5, 116 OP_CB_NOTIFY = 6, 117 OP_CB_PUSH_DELEG = 7, 118 OP_CB_RECALL_ANY = 8, 119 OP_CB_RECALLABLE_OBJ_AVAIL = 9, 120 OP_CB_RECALL_SLOT = 10, 121 OP_CB_SEQUENCE = 11, 122 OP_CB_WANTS_CANCELLED = 12, 123 OP_CB_NOTIFY_LOCK = 13, 124 OP_CB_NOTIFY_DEVICEID = 14, 125 OP_CB_OFFLOAD = 15, 126 OP_CB_ILLEGAL = 10044 127 }; 128 129 static void encode_nfs_cb_opnum4(struct xdr_stream *xdr, enum nfs_cb_opnum4 op) 130 { 131 __be32 *p; 132 133 p = xdr_reserve_space(xdr, 4); 134 *p = cpu_to_be32(op); 135 } 136 137 /* 138 * nfs_fh4 139 * 140 * typedef opaque nfs_fh4<NFS4_FHSIZE>; 141 */ 142 static void encode_nfs_fh4(struct xdr_stream *xdr, const struct knfsd_fh *fh) 143 { 144 u32 length = fh->fh_size; 145 __be32 *p; 146 147 BUG_ON(length > NFS4_FHSIZE); 148 p = xdr_reserve_space(xdr, 4 + length); 149 xdr_encode_opaque(p, &fh->fh_raw, length); 150 } 151 152 /* 153 * stateid4 154 * 155 * struct stateid4 { 156 * uint32_t seqid; 157 * opaque other[12]; 158 * }; 159 */ 160 static void encode_stateid4(struct xdr_stream *xdr, const stateid_t *sid) 161 { 162 __be32 *p; 163 164 p = xdr_reserve_space(xdr, NFS4_STATEID_SIZE); 165 *p++ = cpu_to_be32(sid->si_generation); 166 xdr_encode_opaque_fixed(p, &sid->si_opaque, NFS4_STATEID_OTHER_SIZE); 167 } 168 169 /* 170 * sessionid4 171 * 172 * typedef opaque sessionid4[NFS4_SESSIONID_SIZE]; 173 */ 174 static void encode_sessionid4(struct xdr_stream *xdr, 175 const struct nfsd4_session *session) 176 { 177 __be32 *p; 178 179 p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN); 180 xdr_encode_opaque_fixed(p, session->se_sessionid.data, 181 NFS4_MAX_SESSIONID_LEN); 182 } 183 184 /* 185 * nfsstat4 186 */ 187 static const struct { 188 int stat; 189 int errno; 190 } nfs_cb_errtbl[] = { 191 { NFS4_OK, 0 }, 192 { NFS4ERR_PERM, -EPERM }, 193 { NFS4ERR_NOENT, -ENOENT }, 194 { NFS4ERR_IO, -EIO }, 195 { NFS4ERR_NXIO, -ENXIO }, 196 { NFS4ERR_ACCESS, -EACCES }, 197 { NFS4ERR_EXIST, -EEXIST }, 198 { NFS4ERR_XDEV, -EXDEV }, 199 { NFS4ERR_NOTDIR, -ENOTDIR }, 200 { NFS4ERR_ISDIR, -EISDIR }, 201 { NFS4ERR_INVAL, -EINVAL }, 202 { NFS4ERR_FBIG, -EFBIG }, 203 { NFS4ERR_NOSPC, -ENOSPC }, 204 { NFS4ERR_ROFS, -EROFS }, 205 { NFS4ERR_MLINK, -EMLINK }, 206 { NFS4ERR_NAMETOOLONG, -ENAMETOOLONG }, 207 { NFS4ERR_NOTEMPTY, -ENOTEMPTY }, 208 { NFS4ERR_DQUOT, -EDQUOT }, 209 { NFS4ERR_STALE, -ESTALE }, 210 { NFS4ERR_BADHANDLE, -EBADHANDLE }, 211 { NFS4ERR_BAD_COOKIE, -EBADCOOKIE }, 212 { NFS4ERR_NOTSUPP, -ENOTSUPP }, 213 { NFS4ERR_TOOSMALL, -ETOOSMALL }, 214 { NFS4ERR_SERVERFAULT, -ESERVERFAULT }, 215 { NFS4ERR_BADTYPE, -EBADTYPE }, 216 { NFS4ERR_LOCKED, -EAGAIN }, 217 { NFS4ERR_RESOURCE, -EREMOTEIO }, 218 { NFS4ERR_SYMLINK, -ELOOP }, 219 { NFS4ERR_OP_ILLEGAL, -EOPNOTSUPP }, 220 { NFS4ERR_DEADLOCK, -EDEADLK }, 221 { -1, -EIO } 222 }; 223 224 /* 225 * If we cannot translate the error, the recovery routines should 226 * handle it. 227 * 228 * Note: remaining NFSv4 error codes have values > 10000, so should 229 * not conflict with native Linux error codes. 230 */ 231 static int nfs_cb_stat_to_errno(int status) 232 { 233 int i; 234 235 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 236 if (nfs_cb_errtbl[i].stat == status) 237 return nfs_cb_errtbl[i].errno; 238 } 239 240 dprintk("NFSD: Unrecognized NFS CB status value: %u\n", status); 241 return -status; 242 } 243 244 static int decode_cb_op_status(struct xdr_stream *xdr, 245 enum nfs_cb_opnum4 expected, int *status) 246 { 247 __be32 *p; 248 u32 op; 249 250 p = xdr_inline_decode(xdr, 4 + 4); 251 if (unlikely(p == NULL)) 252 goto out_overflow; 253 op = be32_to_cpup(p++); 254 if (unlikely(op != expected)) 255 goto out_unexpected; 256 *status = nfs_cb_stat_to_errno(be32_to_cpup(p)); 257 return 0; 258 out_overflow: 259 return -EIO; 260 out_unexpected: 261 dprintk("NFSD: Callback server returned operation %d but " 262 "we issued a request for %d\n", op, expected); 263 return -EIO; 264 } 265 266 /* 267 * CB_COMPOUND4args 268 * 269 * struct CB_COMPOUND4args { 270 * utf8str_cs tag; 271 * uint32_t minorversion; 272 * uint32_t callback_ident; 273 * nfs_cb_argop4 argarray<>; 274 * }; 275 */ 276 static void encode_cb_compound4args(struct xdr_stream *xdr, 277 struct nfs4_cb_compound_hdr *hdr) 278 { 279 __be32 * p; 280 281 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4); 282 p = xdr_encode_empty_array(p); /* empty tag */ 283 *p++ = cpu_to_be32(hdr->minorversion); 284 *p++ = cpu_to_be32(hdr->ident); 285 286 hdr->nops_p = p; 287 *p = cpu_to_be32(hdr->nops); /* argarray element count */ 288 } 289 290 /* 291 * Update argarray element count 292 */ 293 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr) 294 { 295 BUG_ON(hdr->nops > NFS4_MAX_BACK_CHANNEL_OPS); 296 *hdr->nops_p = cpu_to_be32(hdr->nops); 297 } 298 299 /* 300 * CB_COMPOUND4res 301 * 302 * struct CB_COMPOUND4res { 303 * nfsstat4 status; 304 * utf8str_cs tag; 305 * nfs_cb_resop4 resarray<>; 306 * }; 307 */ 308 static int decode_cb_compound4res(struct xdr_stream *xdr, 309 struct nfs4_cb_compound_hdr *hdr) 310 { 311 u32 length; 312 __be32 *p; 313 314 p = xdr_inline_decode(xdr, 4 + 4); 315 if (unlikely(p == NULL)) 316 goto out_overflow; 317 hdr->status = be32_to_cpup(p++); 318 /* Ignore the tag */ 319 length = be32_to_cpup(p++); 320 p = xdr_inline_decode(xdr, length + 4); 321 if (unlikely(p == NULL)) 322 goto out_overflow; 323 p += XDR_QUADLEN(length); 324 hdr->nops = be32_to_cpup(p); 325 return 0; 326 out_overflow: 327 return -EIO; 328 } 329 330 /* 331 * CB_RECALL4args 332 * 333 * struct CB_RECALL4args { 334 * stateid4 stateid; 335 * bool truncate; 336 * nfs_fh4 fh; 337 * }; 338 */ 339 static void encode_cb_recall4args(struct xdr_stream *xdr, 340 const struct nfs4_delegation *dp, 341 struct nfs4_cb_compound_hdr *hdr) 342 { 343 __be32 *p; 344 345 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL); 346 encode_stateid4(xdr, &dp->dl_stid.sc_stateid); 347 348 p = xdr_reserve_space(xdr, 4); 349 *p++ = xdr_zero; /* truncate */ 350 351 encode_nfs_fh4(xdr, &dp->dl_stid.sc_file->fi_fhandle); 352 353 hdr->nops++; 354 } 355 356 /* 357 * CB_RECALLANY4args 358 * 359 * struct CB_RECALLANY4args { 360 * uint32_t craa_objects_to_keep; 361 * bitmap4 craa_type_mask; 362 * }; 363 */ 364 static void 365 encode_cb_recallany4args(struct xdr_stream *xdr, 366 struct nfs4_cb_compound_hdr *hdr, struct nfsd4_cb_recall_any *ra) 367 { 368 encode_nfs_cb_opnum4(xdr, OP_CB_RECALL_ANY); 369 encode_uint32(xdr, ra->ra_keep); 370 encode_bitmap4(xdr, ra->ra_bmval, ARRAY_SIZE(ra->ra_bmval)); 371 hdr->nops++; 372 } 373 374 /* 375 * CB_GETATTR4args 376 * struct CB_GETATTR4args { 377 * nfs_fh4 fh; 378 * bitmap4 attr_request; 379 * }; 380 * 381 * The size and change attributes are the only one 382 * guaranteed to be serviced by the client. 383 */ 384 static void 385 encode_cb_getattr4args(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr, 386 struct nfs4_cb_fattr *fattr) 387 { 388 struct nfs4_delegation *dp = 389 container_of(fattr, struct nfs4_delegation, dl_cb_fattr); 390 struct knfsd_fh *fh = &dp->dl_stid.sc_file->fi_fhandle; 391 392 encode_nfs_cb_opnum4(xdr, OP_CB_GETATTR); 393 encode_nfs_fh4(xdr, fh); 394 encode_bitmap4(xdr, fattr->ncf_cb_bmap, ARRAY_SIZE(fattr->ncf_cb_bmap)); 395 hdr->nops++; 396 } 397 398 /* 399 * CB_SEQUENCE4args 400 * 401 * struct CB_SEQUENCE4args { 402 * sessionid4 csa_sessionid; 403 * sequenceid4 csa_sequenceid; 404 * slotid4 csa_slotid; 405 * slotid4 csa_highest_slotid; 406 * bool csa_cachethis; 407 * referring_call_list4 csa_referring_call_lists<>; 408 * }; 409 */ 410 static void encode_cb_sequence4args(struct xdr_stream *xdr, 411 const struct nfsd4_callback *cb, 412 struct nfs4_cb_compound_hdr *hdr) 413 { 414 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 415 __be32 *p; 416 417 if (hdr->minorversion == 0) 418 return; 419 420 encode_nfs_cb_opnum4(xdr, OP_CB_SEQUENCE); 421 encode_sessionid4(xdr, session); 422 423 p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4 + 4); 424 *p++ = cpu_to_be32(session->se_cb_seq_nr); /* csa_sequenceid */ 425 *p++ = xdr_zero; /* csa_slotid */ 426 *p++ = xdr_zero; /* csa_highest_slotid */ 427 *p++ = xdr_zero; /* csa_cachethis */ 428 xdr_encode_empty_array(p); /* csa_referring_call_lists */ 429 430 hdr->nops++; 431 } 432 433 /* 434 * CB_SEQUENCE4resok 435 * 436 * struct CB_SEQUENCE4resok { 437 * sessionid4 csr_sessionid; 438 * sequenceid4 csr_sequenceid; 439 * slotid4 csr_slotid; 440 * slotid4 csr_highest_slotid; 441 * slotid4 csr_target_highest_slotid; 442 * }; 443 * 444 * union CB_SEQUENCE4res switch (nfsstat4 csr_status) { 445 * case NFS4_OK: 446 * CB_SEQUENCE4resok csr_resok4; 447 * default: 448 * void; 449 * }; 450 * 451 * Our current back channel implmentation supports a single backchannel 452 * with a single slot. 453 */ 454 static int decode_cb_sequence4resok(struct xdr_stream *xdr, 455 struct nfsd4_callback *cb) 456 { 457 struct nfsd4_session *session = cb->cb_clp->cl_cb_session; 458 int status = -ESERVERFAULT; 459 __be32 *p; 460 u32 dummy; 461 462 /* 463 * If the server returns different values for sessionID, slotID or 464 * sequence number, the server is looney tunes. 465 */ 466 p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4); 467 if (unlikely(p == NULL)) 468 goto out_overflow; 469 470 if (memcmp(p, session->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) { 471 dprintk("NFS: %s Invalid session id\n", __func__); 472 goto out; 473 } 474 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN); 475 476 dummy = be32_to_cpup(p++); 477 if (dummy != session->se_cb_seq_nr) { 478 dprintk("NFS: %s Invalid sequence number\n", __func__); 479 goto out; 480 } 481 482 dummy = be32_to_cpup(p++); 483 if (dummy != 0) { 484 dprintk("NFS: %s Invalid slotid\n", __func__); 485 goto out; 486 } 487 488 /* 489 * FIXME: process highest slotid and target highest slotid 490 */ 491 status = 0; 492 out: 493 cb->cb_seq_status = status; 494 return status; 495 out_overflow: 496 status = -EIO; 497 goto out; 498 } 499 500 static int decode_cb_sequence4res(struct xdr_stream *xdr, 501 struct nfsd4_callback *cb) 502 { 503 int status; 504 505 if (cb->cb_clp->cl_minorversion == 0) 506 return 0; 507 508 status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status); 509 if (unlikely(status || cb->cb_seq_status)) 510 return status; 511 512 return decode_cb_sequence4resok(xdr, cb); 513 } 514 515 /* 516 * NFSv4.0 and NFSv4.1 XDR encode functions 517 * 518 * NFSv4.0 callback argument types are defined in section 15 of RFC 519 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 520 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 521 * Protocol". 522 */ 523 524 /* 525 * NB: Without this zero space reservation, callbacks over krb5p fail 526 */ 527 static void nfs4_xdr_enc_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 528 const void *__unused) 529 { 530 xdr_reserve_space(xdr, 0); 531 } 532 533 /* 534 * 20.1. Operation 3: CB_GETATTR - Get Attributes 535 */ 536 static void nfs4_xdr_enc_cb_getattr(struct rpc_rqst *req, 537 struct xdr_stream *xdr, const void *data) 538 { 539 const struct nfsd4_callback *cb = data; 540 struct nfs4_cb_fattr *ncf = 541 container_of(cb, struct nfs4_cb_fattr, ncf_getattr); 542 struct nfs4_cb_compound_hdr hdr = { 543 .ident = cb->cb_clp->cl_cb_ident, 544 .minorversion = cb->cb_clp->cl_minorversion, 545 }; 546 547 encode_cb_compound4args(xdr, &hdr); 548 encode_cb_sequence4args(xdr, cb, &hdr); 549 encode_cb_getattr4args(xdr, &hdr, ncf); 550 encode_cb_nops(&hdr); 551 } 552 553 /* 554 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 555 */ 556 static void nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, struct xdr_stream *xdr, 557 const void *data) 558 { 559 const struct nfsd4_callback *cb = data; 560 const struct nfs4_delegation *dp = cb_to_delegation(cb); 561 struct nfs4_cb_compound_hdr hdr = { 562 .ident = cb->cb_clp->cl_cb_ident, 563 .minorversion = cb->cb_clp->cl_minorversion, 564 }; 565 566 encode_cb_compound4args(xdr, &hdr); 567 encode_cb_sequence4args(xdr, cb, &hdr); 568 encode_cb_recall4args(xdr, dp, &hdr); 569 encode_cb_nops(&hdr); 570 } 571 572 /* 573 * 20.6. Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects 574 */ 575 static void 576 nfs4_xdr_enc_cb_recall_any(struct rpc_rqst *req, 577 struct xdr_stream *xdr, const void *data) 578 { 579 const struct nfsd4_callback *cb = data; 580 struct nfsd4_cb_recall_any *ra; 581 struct nfs4_cb_compound_hdr hdr = { 582 .ident = cb->cb_clp->cl_cb_ident, 583 .minorversion = cb->cb_clp->cl_minorversion, 584 }; 585 586 ra = container_of(cb, struct nfsd4_cb_recall_any, ra_cb); 587 encode_cb_compound4args(xdr, &hdr); 588 encode_cb_sequence4args(xdr, cb, &hdr); 589 encode_cb_recallany4args(xdr, &hdr, ra); 590 encode_cb_nops(&hdr); 591 } 592 593 /* 594 * NFSv4.0 and NFSv4.1 XDR decode functions 595 * 596 * NFSv4.0 callback result types are defined in section 15 of RFC 597 * 3530: "Network File System (NFS) version 4 Protocol" and section 20 598 * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1 599 * Protocol". 600 */ 601 602 static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr, 603 void *__unused) 604 { 605 return 0; 606 } 607 608 /* 609 * 20.1. Operation 3: CB_GETATTR - Get Attributes 610 */ 611 static int nfs4_xdr_dec_cb_getattr(struct rpc_rqst *rqstp, 612 struct xdr_stream *xdr, 613 void *data) 614 { 615 struct nfsd4_callback *cb = data; 616 struct nfs4_cb_compound_hdr hdr; 617 int status; 618 u32 bitmap[3] = {0}; 619 u32 attrlen; 620 struct nfs4_cb_fattr *ncf = 621 container_of(cb, struct nfs4_cb_fattr, ncf_getattr); 622 623 status = decode_cb_compound4res(xdr, &hdr); 624 if (unlikely(status)) 625 return status; 626 627 status = decode_cb_sequence4res(xdr, cb); 628 if (unlikely(status || cb->cb_seq_status)) 629 return status; 630 631 status = decode_cb_op_status(xdr, OP_CB_GETATTR, &cb->cb_status); 632 if (status) 633 return status; 634 if (xdr_stream_decode_uint32_array(xdr, bitmap, 3) < 0) 635 return -NFSERR_BAD_XDR; 636 if (xdr_stream_decode_u32(xdr, &attrlen) < 0) 637 return -NFSERR_BAD_XDR; 638 if (attrlen > (sizeof(ncf->ncf_cb_change) + sizeof(ncf->ncf_cb_fsize))) 639 return -NFSERR_BAD_XDR; 640 status = decode_cb_fattr4(xdr, bitmap, ncf); 641 return status; 642 } 643 644 /* 645 * 20.2. Operation 4: CB_RECALL - Recall a Delegation 646 */ 647 static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, 648 struct xdr_stream *xdr, 649 void *data) 650 { 651 struct nfsd4_callback *cb = data; 652 struct nfs4_cb_compound_hdr hdr; 653 int status; 654 655 status = decode_cb_compound4res(xdr, &hdr); 656 if (unlikely(status)) 657 return status; 658 659 status = decode_cb_sequence4res(xdr, cb); 660 if (unlikely(status || cb->cb_seq_status)) 661 return status; 662 663 return decode_cb_op_status(xdr, OP_CB_RECALL, &cb->cb_status); 664 } 665 666 /* 667 * 20.6. Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects 668 */ 669 static int 670 nfs4_xdr_dec_cb_recall_any(struct rpc_rqst *rqstp, 671 struct xdr_stream *xdr, 672 void *data) 673 { 674 struct nfsd4_callback *cb = data; 675 struct nfs4_cb_compound_hdr hdr; 676 int status; 677 678 status = decode_cb_compound4res(xdr, &hdr); 679 if (unlikely(status)) 680 return status; 681 status = decode_cb_sequence4res(xdr, cb); 682 if (unlikely(status || cb->cb_seq_status)) 683 return status; 684 status = decode_cb_op_status(xdr, OP_CB_RECALL_ANY, &cb->cb_status); 685 return status; 686 } 687 688 #ifdef CONFIG_NFSD_PNFS 689 /* 690 * CB_LAYOUTRECALL4args 691 * 692 * struct layoutrecall_file4 { 693 * nfs_fh4 lor_fh; 694 * offset4 lor_offset; 695 * length4 lor_length; 696 * stateid4 lor_stateid; 697 * }; 698 * 699 * union layoutrecall4 switch(layoutrecall_type4 lor_recalltype) { 700 * case LAYOUTRECALL4_FILE: 701 * layoutrecall_file4 lor_layout; 702 * case LAYOUTRECALL4_FSID: 703 * fsid4 lor_fsid; 704 * case LAYOUTRECALL4_ALL: 705 * void; 706 * }; 707 * 708 * struct CB_LAYOUTRECALL4args { 709 * layouttype4 clora_type; 710 * layoutiomode4 clora_iomode; 711 * bool clora_changed; 712 * layoutrecall4 clora_recall; 713 * }; 714 */ 715 static void encode_cb_layout4args(struct xdr_stream *xdr, 716 const struct nfs4_layout_stateid *ls, 717 struct nfs4_cb_compound_hdr *hdr) 718 { 719 __be32 *p; 720 721 BUG_ON(hdr->minorversion == 0); 722 723 p = xdr_reserve_space(xdr, 5 * 4); 724 *p++ = cpu_to_be32(OP_CB_LAYOUTRECALL); 725 *p++ = cpu_to_be32(ls->ls_layout_type); 726 *p++ = cpu_to_be32(IOMODE_ANY); 727 *p++ = cpu_to_be32(1); 728 *p = cpu_to_be32(RETURN_FILE); 729 730 encode_nfs_fh4(xdr, &ls->ls_stid.sc_file->fi_fhandle); 731 732 p = xdr_reserve_space(xdr, 2 * 8); 733 p = xdr_encode_hyper(p, 0); 734 xdr_encode_hyper(p, NFS4_MAX_UINT64); 735 736 encode_stateid4(xdr, &ls->ls_recall_sid); 737 738 hdr->nops++; 739 } 740 741 static void nfs4_xdr_enc_cb_layout(struct rpc_rqst *req, 742 struct xdr_stream *xdr, 743 const void *data) 744 { 745 const struct nfsd4_callback *cb = data; 746 const struct nfs4_layout_stateid *ls = 747 container_of(cb, struct nfs4_layout_stateid, ls_recall); 748 struct nfs4_cb_compound_hdr hdr = { 749 .ident = 0, 750 .minorversion = cb->cb_clp->cl_minorversion, 751 }; 752 753 encode_cb_compound4args(xdr, &hdr); 754 encode_cb_sequence4args(xdr, cb, &hdr); 755 encode_cb_layout4args(xdr, ls, &hdr); 756 encode_cb_nops(&hdr); 757 } 758 759 static int nfs4_xdr_dec_cb_layout(struct rpc_rqst *rqstp, 760 struct xdr_stream *xdr, 761 void *data) 762 { 763 struct nfsd4_callback *cb = data; 764 struct nfs4_cb_compound_hdr hdr; 765 int status; 766 767 status = decode_cb_compound4res(xdr, &hdr); 768 if (unlikely(status)) 769 return status; 770 771 status = decode_cb_sequence4res(xdr, cb); 772 if (unlikely(status || cb->cb_seq_status)) 773 return status; 774 775 return decode_cb_op_status(xdr, OP_CB_LAYOUTRECALL, &cb->cb_status); 776 } 777 #endif /* CONFIG_NFSD_PNFS */ 778 779 static void encode_stateowner(struct xdr_stream *xdr, struct nfs4_stateowner *so) 780 { 781 __be32 *p; 782 783 p = xdr_reserve_space(xdr, 8 + 4 + so->so_owner.len); 784 p = xdr_encode_opaque_fixed(p, &so->so_client->cl_clientid, 8); 785 xdr_encode_opaque(p, so->so_owner.data, so->so_owner.len); 786 } 787 788 static void nfs4_xdr_enc_cb_notify_lock(struct rpc_rqst *req, 789 struct xdr_stream *xdr, 790 const void *data) 791 { 792 const struct nfsd4_callback *cb = data; 793 const struct nfsd4_blocked_lock *nbl = 794 container_of(cb, struct nfsd4_blocked_lock, nbl_cb); 795 struct nfs4_lockowner *lo = (struct nfs4_lockowner *)nbl->nbl_lock.fl_owner; 796 struct nfs4_cb_compound_hdr hdr = { 797 .ident = 0, 798 .minorversion = cb->cb_clp->cl_minorversion, 799 }; 800 801 __be32 *p; 802 803 BUG_ON(hdr.minorversion == 0); 804 805 encode_cb_compound4args(xdr, &hdr); 806 encode_cb_sequence4args(xdr, cb, &hdr); 807 808 p = xdr_reserve_space(xdr, 4); 809 *p = cpu_to_be32(OP_CB_NOTIFY_LOCK); 810 encode_nfs_fh4(xdr, &nbl->nbl_fh); 811 encode_stateowner(xdr, &lo->lo_owner); 812 hdr.nops++; 813 814 encode_cb_nops(&hdr); 815 } 816 817 static int nfs4_xdr_dec_cb_notify_lock(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_NOTIFY_LOCK, &cb->cb_status); 834 } 835 836 /* 837 * struct write_response4 { 838 * stateid4 wr_callback_id<1>; 839 * length4 wr_count; 840 * stable_how4 wr_committed; 841 * verifier4 wr_writeverf; 842 * }; 843 * union offload_info4 switch (nfsstat4 coa_status) { 844 * case NFS4_OK: 845 * write_response4 coa_resok4; 846 * default: 847 * length4 coa_bytes_copied; 848 * }; 849 * struct CB_OFFLOAD4args { 850 * nfs_fh4 coa_fh; 851 * stateid4 coa_stateid; 852 * offload_info4 coa_offload_info; 853 * }; 854 */ 855 static void encode_offload_info4(struct xdr_stream *xdr, 856 const struct nfsd4_cb_offload *cbo) 857 { 858 __be32 *p; 859 860 p = xdr_reserve_space(xdr, 4); 861 *p = cbo->co_nfserr; 862 switch (cbo->co_nfserr) { 863 case nfs_ok: 864 p = xdr_reserve_space(xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE); 865 p = xdr_encode_empty_array(p); 866 p = xdr_encode_hyper(p, cbo->co_res.wr_bytes_written); 867 *p++ = cpu_to_be32(cbo->co_res.wr_stable_how); 868 p = xdr_encode_opaque_fixed(p, cbo->co_res.wr_verifier.data, 869 NFS4_VERIFIER_SIZE); 870 break; 871 default: 872 p = xdr_reserve_space(xdr, 8); 873 /* We always return success if bytes were written */ 874 p = xdr_encode_hyper(p, 0); 875 } 876 } 877 878 static void encode_cb_offload4args(struct xdr_stream *xdr, 879 const struct nfsd4_cb_offload *cbo, 880 struct nfs4_cb_compound_hdr *hdr) 881 { 882 __be32 *p; 883 884 p = xdr_reserve_space(xdr, 4); 885 *p = cpu_to_be32(OP_CB_OFFLOAD); 886 encode_nfs_fh4(xdr, &cbo->co_fh); 887 encode_stateid4(xdr, &cbo->co_res.cb_stateid); 888 encode_offload_info4(xdr, cbo); 889 890 hdr->nops++; 891 } 892 893 static void nfs4_xdr_enc_cb_offload(struct rpc_rqst *req, 894 struct xdr_stream *xdr, 895 const void *data) 896 { 897 const struct nfsd4_callback *cb = data; 898 const struct nfsd4_cb_offload *cbo = 899 container_of(cb, struct nfsd4_cb_offload, co_cb); 900 struct nfs4_cb_compound_hdr hdr = { 901 .ident = 0, 902 .minorversion = cb->cb_clp->cl_minorversion, 903 }; 904 905 encode_cb_compound4args(xdr, &hdr); 906 encode_cb_sequence4args(xdr, cb, &hdr); 907 encode_cb_offload4args(xdr, cbo, &hdr); 908 encode_cb_nops(&hdr); 909 } 910 911 static int nfs4_xdr_dec_cb_offload(struct rpc_rqst *rqstp, 912 struct xdr_stream *xdr, 913 void *data) 914 { 915 struct nfsd4_callback *cb = data; 916 struct nfs4_cb_compound_hdr hdr; 917 int status; 918 919 status = decode_cb_compound4res(xdr, &hdr); 920 if (unlikely(status)) 921 return status; 922 923 status = decode_cb_sequence4res(xdr, cb); 924 if (unlikely(status || cb->cb_seq_status)) 925 return status; 926 927 return decode_cb_op_status(xdr, OP_CB_OFFLOAD, &cb->cb_status); 928 } 929 /* 930 * RPC procedure tables 931 */ 932 #define PROC(proc, call, argtype, restype) \ 933 [NFSPROC4_CLNT_##proc] = { \ 934 .p_proc = NFSPROC4_CB_##call, \ 935 .p_encode = nfs4_xdr_enc_##argtype, \ 936 .p_decode = nfs4_xdr_dec_##restype, \ 937 .p_arglen = NFS4_enc_##argtype##_sz, \ 938 .p_replen = NFS4_dec_##restype##_sz, \ 939 .p_statidx = NFSPROC4_CB_##call, \ 940 .p_name = #proc, \ 941 } 942 943 static const struct rpc_procinfo nfs4_cb_procedures[] = { 944 PROC(CB_NULL, NULL, cb_null, cb_null), 945 PROC(CB_RECALL, COMPOUND, cb_recall, cb_recall), 946 #ifdef CONFIG_NFSD_PNFS 947 PROC(CB_LAYOUT, COMPOUND, cb_layout, cb_layout), 948 #endif 949 PROC(CB_NOTIFY_LOCK, COMPOUND, cb_notify_lock, cb_notify_lock), 950 PROC(CB_OFFLOAD, COMPOUND, cb_offload, cb_offload), 951 PROC(CB_RECALL_ANY, COMPOUND, cb_recall_any, cb_recall_any), 952 PROC(CB_GETATTR, COMPOUND, cb_getattr, cb_getattr), 953 }; 954 955 static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)]; 956 static const struct rpc_version nfs_cb_version4 = { 957 /* 958 * Note on the callback rpc program version number: despite language in rfc 959 * 5661 section 18.36.3 requiring servers to use 4 in this field, the 960 * official xdr descriptions for both 4.0 and 4.1 specify version 1, and 961 * in practice that appears to be what implementations use. The section 962 * 18.36.3 language is expected to be fixed in an erratum. 963 */ 964 .number = 1, 965 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 966 .procs = nfs4_cb_procedures, 967 .counts = nfs4_cb_counts, 968 }; 969 970 static const struct rpc_version *nfs_cb_version[2] = { 971 [1] = &nfs_cb_version4, 972 }; 973 974 static const struct rpc_program cb_program; 975 976 static struct rpc_stat cb_stats = { 977 .program = &cb_program 978 }; 979 980 #define NFS4_CALLBACK 0x40000000 981 static const struct rpc_program cb_program = { 982 .name = "nfs4_cb", 983 .number = NFS4_CALLBACK, 984 .nrvers = ARRAY_SIZE(nfs_cb_version), 985 .version = nfs_cb_version, 986 .stats = &cb_stats, 987 .pipe_dir_name = "nfsd4_cb", 988 }; 989 990 static int max_cb_time(struct net *net) 991 { 992 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 993 994 /* 995 * nfsd4_lease is set to at most one hour in __nfsd4_write_time, 996 * so we can use 32-bit math on it. Warn if that assumption 997 * ever stops being true. 998 */ 999 if (WARN_ON_ONCE(nn->nfsd4_lease > 3600)) 1000 return 360 * HZ; 1001 1002 return max(((u32)nn->nfsd4_lease)/10, 1u) * HZ; 1003 } 1004 1005 static struct workqueue_struct *callback_wq; 1006 1007 static bool nfsd4_queue_cb(struct nfsd4_callback *cb) 1008 { 1009 return queue_work(callback_wq, &cb->cb_work); 1010 } 1011 1012 static void nfsd41_cb_inflight_begin(struct nfs4_client *clp) 1013 { 1014 atomic_inc(&clp->cl_cb_inflight); 1015 } 1016 1017 static void nfsd41_cb_inflight_end(struct nfs4_client *clp) 1018 { 1019 1020 if (atomic_dec_and_test(&clp->cl_cb_inflight)) 1021 wake_up_var(&clp->cl_cb_inflight); 1022 } 1023 1024 static void nfsd41_cb_inflight_wait_complete(struct nfs4_client *clp) 1025 { 1026 wait_var_event(&clp->cl_cb_inflight, 1027 !atomic_read(&clp->cl_cb_inflight)); 1028 } 1029 1030 static const struct cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc_clnt *client, struct nfsd4_session *ses) 1031 { 1032 if (clp->cl_minorversion == 0) { 1033 client->cl_principal = clp->cl_cred.cr_targ_princ ? 1034 clp->cl_cred.cr_targ_princ : "nfs"; 1035 1036 return get_cred(rpc_machine_cred()); 1037 } else { 1038 struct cred *kcred; 1039 1040 kcred = prepare_kernel_cred(&init_task); 1041 if (!kcred) 1042 return NULL; 1043 1044 kcred->fsuid = ses->se_cb_sec.uid; 1045 kcred->fsgid = ses->se_cb_sec.gid; 1046 return kcred; 1047 } 1048 } 1049 1050 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses) 1051 { 1052 int maxtime = max_cb_time(clp->net); 1053 struct rpc_timeout timeparms = { 1054 .to_initval = maxtime, 1055 .to_retries = 0, 1056 .to_maxval = maxtime, 1057 }; 1058 struct rpc_create_args args = { 1059 .net = clp->net, 1060 .address = (struct sockaddr *) &conn->cb_addr, 1061 .addrsize = conn->cb_addrlen, 1062 .saddress = (struct sockaddr *) &conn->cb_saddr, 1063 .timeout = &timeparms, 1064 .program = &cb_program, 1065 .version = 1, 1066 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), 1067 .cred = current_cred(), 1068 }; 1069 struct rpc_clnt *client; 1070 const struct cred *cred; 1071 1072 if (clp->cl_minorversion == 0) { 1073 if (!clp->cl_cred.cr_principal && 1074 (clp->cl_cred.cr_flavor >= RPC_AUTH_GSS_KRB5)) { 1075 trace_nfsd_cb_setup_err(clp, -EINVAL); 1076 return -EINVAL; 1077 } 1078 args.client_name = clp->cl_cred.cr_principal; 1079 args.prognumber = conn->cb_prog; 1080 args.protocol = XPRT_TRANSPORT_TCP; 1081 args.authflavor = clp->cl_cred.cr_flavor; 1082 clp->cl_cb_ident = conn->cb_ident; 1083 } else { 1084 if (!conn->cb_xprt) 1085 return -EINVAL; 1086 clp->cl_cb_session = ses; 1087 args.bc_xprt = conn->cb_xprt; 1088 args.prognumber = clp->cl_cb_session->se_cb_prog; 1089 args.protocol = conn->cb_xprt->xpt_class->xcl_ident | 1090 XPRT_TRANSPORT_BC; 1091 args.authflavor = ses->se_cb_sec.flavor; 1092 } 1093 /* Create RPC client */ 1094 client = rpc_create(&args); 1095 if (IS_ERR(client)) { 1096 trace_nfsd_cb_setup_err(clp, PTR_ERR(client)); 1097 return PTR_ERR(client); 1098 } 1099 cred = get_backchannel_cred(clp, client, ses); 1100 if (!cred) { 1101 trace_nfsd_cb_setup_err(clp, -ENOMEM); 1102 rpc_shutdown_client(client); 1103 return -ENOMEM; 1104 } 1105 1106 if (clp->cl_minorversion != 0) 1107 clp->cl_cb_conn.cb_xprt = conn->cb_xprt; 1108 clp->cl_cb_client = client; 1109 clp->cl_cb_cred = cred; 1110 rcu_read_lock(); 1111 trace_nfsd_cb_setup(clp, rpc_peeraddr2str(client, RPC_DISPLAY_NETID), 1112 args.authflavor); 1113 rcu_read_unlock(); 1114 return 0; 1115 } 1116 1117 static void nfsd4_mark_cb_state(struct nfs4_client *clp, int newstate) 1118 { 1119 if (clp->cl_cb_state != newstate) { 1120 clp->cl_cb_state = newstate; 1121 trace_nfsd_cb_state(clp); 1122 } 1123 } 1124 1125 static void nfsd4_mark_cb_down(struct nfs4_client *clp, int reason) 1126 { 1127 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 1128 return; 1129 nfsd4_mark_cb_state(clp, NFSD4_CB_DOWN); 1130 } 1131 1132 static void nfsd4_mark_cb_fault(struct nfs4_client *clp, int reason) 1133 { 1134 if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags)) 1135 return; 1136 nfsd4_mark_cb_state(clp, NFSD4_CB_FAULT); 1137 } 1138 1139 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata) 1140 { 1141 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 1142 1143 if (task->tk_status) 1144 nfsd4_mark_cb_down(clp, task->tk_status); 1145 else 1146 nfsd4_mark_cb_state(clp, NFSD4_CB_UP); 1147 } 1148 1149 static void nfsd4_cb_probe_release(void *calldata) 1150 { 1151 struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null); 1152 1153 nfsd41_cb_inflight_end(clp); 1154 1155 } 1156 1157 static const struct rpc_call_ops nfsd4_cb_probe_ops = { 1158 /* XXX: release method to ensure we set the cb channel down if 1159 * necessary on early failure? */ 1160 .rpc_call_done = nfsd4_cb_probe_done, 1161 .rpc_release = nfsd4_cb_probe_release, 1162 }; 1163 1164 /* 1165 * Poke the callback thread to process any updates to the callback 1166 * parameters, and send a null probe. 1167 */ 1168 void nfsd4_probe_callback(struct nfs4_client *clp) 1169 { 1170 trace_nfsd_cb_probe(clp); 1171 nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN); 1172 set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1173 nfsd4_run_cb(&clp->cl_cb_null); 1174 } 1175 1176 void nfsd4_probe_callback_sync(struct nfs4_client *clp) 1177 { 1178 nfsd4_probe_callback(clp); 1179 flush_workqueue(callback_wq); 1180 } 1181 1182 void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn) 1183 { 1184 nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN); 1185 spin_lock(&clp->cl_lock); 1186 memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn)); 1187 spin_unlock(&clp->cl_lock); 1188 } 1189 1190 /* 1191 * There's currently a single callback channel slot. 1192 * If the slot is available, then mark it busy. Otherwise, set the 1193 * thread for sleeping on the callback RPC wait queue. 1194 */ 1195 static bool nfsd41_cb_get_slot(struct nfsd4_callback *cb, struct rpc_task *task) 1196 { 1197 struct nfs4_client *clp = cb->cb_clp; 1198 1199 if (!cb->cb_holds_slot && 1200 test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 1201 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL); 1202 /* Race breaker */ 1203 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 1204 dprintk("%s slot is busy\n", __func__); 1205 return false; 1206 } 1207 rpc_wake_up_queued_task(&clp->cl_cb_waitq, task); 1208 } 1209 cb->cb_holds_slot = true; 1210 return true; 1211 } 1212 1213 static void nfsd41_cb_release_slot(struct nfsd4_callback *cb) 1214 { 1215 struct nfs4_client *clp = cb->cb_clp; 1216 1217 if (cb->cb_holds_slot) { 1218 cb->cb_holds_slot = false; 1219 clear_bit(0, &clp->cl_cb_slot_busy); 1220 rpc_wake_up_next(&clp->cl_cb_waitq); 1221 } 1222 } 1223 1224 static void nfsd41_destroy_cb(struct nfsd4_callback *cb) 1225 { 1226 struct nfs4_client *clp = cb->cb_clp; 1227 1228 nfsd41_cb_release_slot(cb); 1229 if (cb->cb_ops && cb->cb_ops->release) 1230 cb->cb_ops->release(cb); 1231 nfsd41_cb_inflight_end(clp); 1232 } 1233 1234 /* 1235 * TODO: cb_sequence should support referring call lists, cachethis, multiple 1236 * slots, and mark callback channel down on communication errors. 1237 */ 1238 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata) 1239 { 1240 struct nfsd4_callback *cb = calldata; 1241 struct nfs4_client *clp = cb->cb_clp; 1242 u32 minorversion = clp->cl_minorversion; 1243 1244 /* 1245 * cb_seq_status is only set in decode_cb_sequence4res, 1246 * and so will remain 1 if an rpc level failure occurs. 1247 */ 1248 cb->cb_seq_status = 1; 1249 cb->cb_status = 0; 1250 if (minorversion && !nfsd41_cb_get_slot(cb, task)) 1251 return; 1252 rpc_call_start(task); 1253 } 1254 1255 static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback *cb) 1256 { 1257 struct nfs4_client *clp = cb->cb_clp; 1258 struct nfsd4_session *session = clp->cl_cb_session; 1259 bool ret = true; 1260 1261 if (!clp->cl_minorversion) { 1262 /* 1263 * If the backchannel connection was shut down while this 1264 * task was queued, we need to resubmit it after setting up 1265 * a new backchannel connection. 1266 * 1267 * Note that if we lost our callback connection permanently 1268 * the submission code will error out, so we don't need to 1269 * handle that case here. 1270 */ 1271 if (RPC_SIGNALLED(task)) 1272 goto need_restart; 1273 1274 return true; 1275 } 1276 1277 if (!cb->cb_holds_slot) 1278 goto need_restart; 1279 1280 switch (cb->cb_seq_status) { 1281 case 0: 1282 /* 1283 * No need for lock, access serialized in nfsd4_cb_prepare 1284 * 1285 * RFC5661 20.9.3 1286 * If CB_SEQUENCE returns an error, then the state of the slot 1287 * (sequence ID, cached reply) MUST NOT change. 1288 */ 1289 ++session->se_cb_seq_nr; 1290 break; 1291 case -ESERVERFAULT: 1292 ++session->se_cb_seq_nr; 1293 fallthrough; 1294 case 1: 1295 case -NFS4ERR_BADSESSION: 1296 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 1297 ret = false; 1298 break; 1299 case -NFS4ERR_DELAY: 1300 if (!rpc_restart_call(task)) 1301 goto out; 1302 1303 rpc_delay(task, 2 * HZ); 1304 return false; 1305 case -NFS4ERR_BADSLOT: 1306 goto retry_nowait; 1307 case -NFS4ERR_SEQ_MISORDERED: 1308 if (session->se_cb_seq_nr != 1) { 1309 session->se_cb_seq_nr = 1; 1310 goto retry_nowait; 1311 } 1312 break; 1313 default: 1314 nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status); 1315 dprintk("%s: unprocessed error %d\n", __func__, 1316 cb->cb_seq_status); 1317 } 1318 1319 nfsd41_cb_release_slot(cb); 1320 dprintk("%s: freed slot, new seqid=%d\n", __func__, 1321 clp->cl_cb_session->se_cb_seq_nr); 1322 1323 if (RPC_SIGNALLED(task)) 1324 goto need_restart; 1325 out: 1326 return ret; 1327 retry_nowait: 1328 if (rpc_restart_call_prepare(task)) 1329 ret = false; 1330 goto out; 1331 need_restart: 1332 if (!test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) { 1333 task->tk_status = 0; 1334 cb->cb_need_restart = true; 1335 } 1336 return false; 1337 } 1338 1339 static void nfsd4_cb_done(struct rpc_task *task, void *calldata) 1340 { 1341 struct nfsd4_callback *cb = calldata; 1342 struct nfs4_client *clp = cb->cb_clp; 1343 1344 if (!nfsd4_cb_sequence_done(task, cb)) 1345 return; 1346 1347 if (cb->cb_status) { 1348 WARN_ON_ONCE(task->tk_status); 1349 task->tk_status = cb->cb_status; 1350 } 1351 1352 switch (cb->cb_ops->done(cb, task)) { 1353 case 0: 1354 task->tk_status = 0; 1355 rpc_restart_call_prepare(task); 1356 return; 1357 case 1: 1358 switch (task->tk_status) { 1359 case -EIO: 1360 case -ETIMEDOUT: 1361 case -EACCES: 1362 nfsd4_mark_cb_down(clp, task->tk_status); 1363 } 1364 break; 1365 default: 1366 BUG(); 1367 } 1368 } 1369 1370 static void nfsd4_cb_release(void *calldata) 1371 { 1372 struct nfsd4_callback *cb = calldata; 1373 1374 if (cb->cb_need_restart) 1375 nfsd4_queue_cb(cb); 1376 else 1377 nfsd41_destroy_cb(cb); 1378 1379 } 1380 1381 static const struct rpc_call_ops nfsd4_cb_ops = { 1382 .rpc_call_prepare = nfsd4_cb_prepare, 1383 .rpc_call_done = nfsd4_cb_done, 1384 .rpc_release = nfsd4_cb_release, 1385 }; 1386 1387 int nfsd4_create_callback_queue(void) 1388 { 1389 callback_wq = alloc_ordered_workqueue("nfsd4_callbacks", 0); 1390 if (!callback_wq) 1391 return -ENOMEM; 1392 return 0; 1393 } 1394 1395 void nfsd4_destroy_callback_queue(void) 1396 { 1397 destroy_workqueue(callback_wq); 1398 } 1399 1400 /* must be called under the state lock */ 1401 void nfsd4_shutdown_callback(struct nfs4_client *clp) 1402 { 1403 if (clp->cl_cb_state != NFSD4_CB_UNKNOWN) 1404 trace_nfsd_cb_shutdown(clp); 1405 1406 set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags); 1407 /* 1408 * Note this won't actually result in a null callback; 1409 * instead, nfsd4_run_cb_null() will detect the killed 1410 * client, destroy the rpc client, and stop: 1411 */ 1412 nfsd4_run_cb(&clp->cl_cb_null); 1413 flush_workqueue(callback_wq); 1414 nfsd41_cb_inflight_wait_complete(clp); 1415 } 1416 1417 /* requires cl_lock: */ 1418 static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp) 1419 { 1420 struct nfsd4_session *s; 1421 struct nfsd4_conn *c; 1422 1423 list_for_each_entry(s, &clp->cl_sessions, se_perclnt) { 1424 list_for_each_entry(c, &s->se_conns, cn_persession) { 1425 if (c->cn_flags & NFS4_CDFC4_BACK) 1426 return c; 1427 } 1428 } 1429 return NULL; 1430 } 1431 1432 /* 1433 * Note there isn't a lot of locking in this code; instead we depend on 1434 * the fact that it is run from the callback_wq, which won't run two 1435 * work items at once. So, for example, callback_wq handles all access 1436 * of cl_cb_client and all calls to rpc_create or rpc_shutdown_client. 1437 */ 1438 static void nfsd4_process_cb_update(struct nfsd4_callback *cb) 1439 { 1440 struct nfs4_cb_conn conn; 1441 struct nfs4_client *clp = cb->cb_clp; 1442 struct nfsd4_session *ses = NULL; 1443 struct nfsd4_conn *c; 1444 int err; 1445 1446 /* 1447 * This is either an update, or the client dying; in either case, 1448 * kill the old client: 1449 */ 1450 if (clp->cl_cb_client) { 1451 rpc_shutdown_client(clp->cl_cb_client); 1452 clp->cl_cb_client = NULL; 1453 put_cred(clp->cl_cb_cred); 1454 clp->cl_cb_cred = NULL; 1455 } 1456 if (clp->cl_cb_conn.cb_xprt) { 1457 svc_xprt_put(clp->cl_cb_conn.cb_xprt); 1458 clp->cl_cb_conn.cb_xprt = NULL; 1459 } 1460 if (test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags)) 1461 return; 1462 spin_lock(&clp->cl_lock); 1463 /* 1464 * Only serialized callback code is allowed to clear these 1465 * flags; main nfsd code can only set them: 1466 */ 1467 BUG_ON(!(clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK)); 1468 clear_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags); 1469 memcpy(&conn, &cb->cb_clp->cl_cb_conn, sizeof(struct nfs4_cb_conn)); 1470 c = __nfsd4_find_backchannel(clp); 1471 if (c) { 1472 svc_xprt_get(c->cn_xprt); 1473 conn.cb_xprt = c->cn_xprt; 1474 ses = c->cn_session; 1475 } 1476 spin_unlock(&clp->cl_lock); 1477 1478 err = setup_callback_client(clp, &conn, ses); 1479 if (err) { 1480 nfsd4_mark_cb_down(clp, err); 1481 if (c) 1482 svc_xprt_put(c->cn_xprt); 1483 return; 1484 } 1485 } 1486 1487 static void 1488 nfsd4_run_cb_work(struct work_struct *work) 1489 { 1490 struct nfsd4_callback *cb = 1491 container_of(work, struct nfsd4_callback, cb_work); 1492 struct nfs4_client *clp = cb->cb_clp; 1493 struct rpc_clnt *clnt; 1494 int flags; 1495 1496 if (cb->cb_need_restart) { 1497 cb->cb_need_restart = false; 1498 } else { 1499 if (cb->cb_ops && cb->cb_ops->prepare) 1500 cb->cb_ops->prepare(cb); 1501 } 1502 1503 if (clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK) 1504 nfsd4_process_cb_update(cb); 1505 1506 clnt = clp->cl_cb_client; 1507 if (!clnt) { 1508 /* Callback channel broken, or client killed; give up: */ 1509 nfsd41_destroy_cb(cb); 1510 return; 1511 } 1512 1513 /* 1514 * Don't send probe messages for 4.1 or later. 1515 */ 1516 if (!cb->cb_ops && clp->cl_minorversion) { 1517 nfsd4_mark_cb_state(clp, NFSD4_CB_UP); 1518 nfsd41_destroy_cb(cb); 1519 return; 1520 } 1521 1522 cb->cb_msg.rpc_cred = clp->cl_cb_cred; 1523 flags = clp->cl_minorversion ? RPC_TASK_NOCONNECT : RPC_TASK_SOFTCONN; 1524 rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | flags, 1525 cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb); 1526 } 1527 1528 void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, 1529 const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op) 1530 { 1531 cb->cb_clp = clp; 1532 cb->cb_msg.rpc_proc = &nfs4_cb_procedures[op]; 1533 cb->cb_msg.rpc_argp = cb; 1534 cb->cb_msg.rpc_resp = cb; 1535 cb->cb_ops = ops; 1536 INIT_WORK(&cb->cb_work, nfsd4_run_cb_work); 1537 cb->cb_seq_status = 1; 1538 cb->cb_status = 0; 1539 cb->cb_need_restart = false; 1540 cb->cb_holds_slot = false; 1541 } 1542 1543 /** 1544 * nfsd4_run_cb - queue up a callback job to run 1545 * @cb: callback to queue 1546 * 1547 * Kick off a callback to do its thing. Returns false if it was already 1548 * on a queue, true otherwise. 1549 */ 1550 bool nfsd4_run_cb(struct nfsd4_callback *cb) 1551 { 1552 struct nfs4_client *clp = cb->cb_clp; 1553 bool queued; 1554 1555 nfsd41_cb_inflight_begin(clp); 1556 queued = nfsd4_queue_cb(cb); 1557 if (!queued) 1558 nfsd41_cb_inflight_end(clp); 1559 return queued; 1560 } 1561