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/slab.h> 36 #include "nfsd.h" 37 #include "state.h" 38 39 #define NFSDDBG_FACILITY NFSDDBG_PROC 40 41 #define NFSPROC4_CB_NULL 0 42 #define NFSPROC4_CB_COMPOUND 1 43 #define NFS4_STATEID_SIZE 16 44 45 /* Index of predefined Linux callback client operations */ 46 47 enum { 48 NFSPROC4_CLNT_CB_NULL = 0, 49 NFSPROC4_CLNT_CB_RECALL, 50 NFSPROC4_CLNT_CB_SEQUENCE, 51 }; 52 53 enum nfs_cb_opnum4 { 54 OP_CB_RECALL = 4, 55 OP_CB_SEQUENCE = 11, 56 }; 57 58 #define NFS4_MAXTAGLEN 20 59 60 #define NFS4_enc_cb_null_sz 0 61 #define NFS4_dec_cb_null_sz 0 62 #define cb_compound_enc_hdr_sz 4 63 #define cb_compound_dec_hdr_sz (3 + (NFS4_MAXTAGLEN >> 2)) 64 #define sessionid_sz (NFS4_MAX_SESSIONID_LEN >> 2) 65 #define cb_sequence_enc_sz (sessionid_sz + 4 + \ 66 1 /* no referring calls list yet */) 67 #define cb_sequence_dec_sz (op_dec_sz + sessionid_sz + 4) 68 69 #define op_enc_sz 1 70 #define op_dec_sz 2 71 #define enc_nfs4_fh_sz (1 + (NFS4_FHSIZE >> 2)) 72 #define enc_stateid_sz (NFS4_STATEID_SIZE >> 2) 73 #define NFS4_enc_cb_recall_sz (cb_compound_enc_hdr_sz + \ 74 cb_sequence_enc_sz + \ 75 1 + enc_stateid_sz + \ 76 enc_nfs4_fh_sz) 77 78 #define NFS4_dec_cb_recall_sz (cb_compound_dec_hdr_sz + \ 79 cb_sequence_dec_sz + \ 80 op_dec_sz) 81 82 struct nfs4_rpc_args { 83 void *args_op; 84 struct nfsd4_cb_sequence args_seq; 85 }; 86 87 /* 88 * Generic encode routines from fs/nfs/nfs4xdr.c 89 */ 90 static inline __be32 * 91 xdr_writemem(__be32 *p, const void *ptr, int nbytes) 92 { 93 int tmp = XDR_QUADLEN(nbytes); 94 if (!tmp) 95 return p; 96 p[tmp-1] = 0; 97 memcpy(p, ptr, nbytes); 98 return p + tmp; 99 } 100 101 #define WRITE32(n) *p++ = htonl(n) 102 #define WRITEMEM(ptr,nbytes) do { \ 103 p = xdr_writemem(p, ptr, nbytes); \ 104 } while (0) 105 #define RESERVE_SPACE(nbytes) do { \ 106 p = xdr_reserve_space(xdr, nbytes); \ 107 if (!p) dprintk("NFSD: RESERVE_SPACE(%d) failed in function %s\n", (int) (nbytes), __func__); \ 108 BUG_ON(!p); \ 109 } while (0) 110 111 /* 112 * Generic decode routines from fs/nfs/nfs4xdr.c 113 */ 114 #define DECODE_TAIL \ 115 status = 0; \ 116 out: \ 117 return status; \ 118 xdr_error: \ 119 dprintk("NFSD: xdr error! (%s:%d)\n", __FILE__, __LINE__); \ 120 status = -EIO; \ 121 goto out 122 123 #define READ32(x) (x) = ntohl(*p++) 124 #define READ64(x) do { \ 125 (x) = (u64)ntohl(*p++) << 32; \ 126 (x) |= ntohl(*p++); \ 127 } while (0) 128 #define READTIME(x) do { \ 129 p++; \ 130 (x.tv_sec) = ntohl(*p++); \ 131 (x.tv_nsec) = ntohl(*p++); \ 132 } while (0) 133 #define READ_BUF(nbytes) do { \ 134 p = xdr_inline_decode(xdr, nbytes); \ 135 if (!p) { \ 136 dprintk("NFSD: %s: reply buffer overflowed in line %d.\n", \ 137 __func__, __LINE__); \ 138 return -EIO; \ 139 } \ 140 } while (0) 141 142 struct nfs4_cb_compound_hdr { 143 /* args */ 144 u32 ident; /* minorversion 0 only */ 145 u32 nops; 146 __be32 *nops_p; 147 u32 minorversion; 148 /* res */ 149 int status; 150 u32 taglen; 151 char *tag; 152 }; 153 154 static struct { 155 int stat; 156 int errno; 157 } nfs_cb_errtbl[] = { 158 { NFS4_OK, 0 }, 159 { NFS4ERR_PERM, EPERM }, 160 { NFS4ERR_NOENT, ENOENT }, 161 { NFS4ERR_IO, EIO }, 162 { NFS4ERR_NXIO, ENXIO }, 163 { NFS4ERR_ACCESS, EACCES }, 164 { NFS4ERR_EXIST, EEXIST }, 165 { NFS4ERR_XDEV, EXDEV }, 166 { NFS4ERR_NOTDIR, ENOTDIR }, 167 { NFS4ERR_ISDIR, EISDIR }, 168 { NFS4ERR_INVAL, EINVAL }, 169 { NFS4ERR_FBIG, EFBIG }, 170 { NFS4ERR_NOSPC, ENOSPC }, 171 { NFS4ERR_ROFS, EROFS }, 172 { NFS4ERR_MLINK, EMLINK }, 173 { NFS4ERR_NAMETOOLONG, ENAMETOOLONG }, 174 { NFS4ERR_NOTEMPTY, ENOTEMPTY }, 175 { NFS4ERR_DQUOT, EDQUOT }, 176 { NFS4ERR_STALE, ESTALE }, 177 { NFS4ERR_BADHANDLE, EBADHANDLE }, 178 { NFS4ERR_BAD_COOKIE, EBADCOOKIE }, 179 { NFS4ERR_NOTSUPP, ENOTSUPP }, 180 { NFS4ERR_TOOSMALL, ETOOSMALL }, 181 { NFS4ERR_SERVERFAULT, ESERVERFAULT }, 182 { NFS4ERR_BADTYPE, EBADTYPE }, 183 { NFS4ERR_LOCKED, EAGAIN }, 184 { NFS4ERR_RESOURCE, EREMOTEIO }, 185 { NFS4ERR_SYMLINK, ELOOP }, 186 { NFS4ERR_OP_ILLEGAL, EOPNOTSUPP }, 187 { NFS4ERR_DEADLOCK, EDEADLK }, 188 { -1, EIO } 189 }; 190 191 static int 192 nfs_cb_stat_to_errno(int stat) 193 { 194 int i; 195 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { 196 if (nfs_cb_errtbl[i].stat == stat) 197 return nfs_cb_errtbl[i].errno; 198 } 199 /* If we cannot translate the error, the recovery routines should 200 * handle it. 201 * Note: remaining NFSv4 error codes have values > 10000, so should 202 * not conflict with native Linux error codes. 203 */ 204 return stat; 205 } 206 207 /* 208 * XDR encode 209 */ 210 211 static void 212 encode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr) 213 { 214 __be32 * p; 215 216 RESERVE_SPACE(16); 217 WRITE32(0); /* tag length is always 0 */ 218 WRITE32(hdr->minorversion); 219 WRITE32(hdr->ident); 220 hdr->nops_p = p; 221 WRITE32(hdr->nops); 222 } 223 224 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr) 225 { 226 *hdr->nops_p = htonl(hdr->nops); 227 } 228 229 static void 230 encode_cb_recall(struct xdr_stream *xdr, struct nfs4_delegation *dp, 231 struct nfs4_cb_compound_hdr *hdr) 232 { 233 __be32 *p; 234 int len = dp->dl_fh.fh_size; 235 236 RESERVE_SPACE(12+sizeof(dp->dl_stateid) + len); 237 WRITE32(OP_CB_RECALL); 238 WRITE32(dp->dl_stateid.si_generation); 239 WRITEMEM(&dp->dl_stateid.si_opaque, sizeof(stateid_opaque_t)); 240 WRITE32(0); /* truncate optimization not implemented */ 241 WRITE32(len); 242 WRITEMEM(&dp->dl_fh.fh_base, len); 243 hdr->nops++; 244 } 245 246 static void 247 encode_cb_sequence(struct xdr_stream *xdr, struct nfsd4_cb_sequence *args, 248 struct nfs4_cb_compound_hdr *hdr) 249 { 250 __be32 *p; 251 252 if (hdr->minorversion == 0) 253 return; 254 255 RESERVE_SPACE(1 + NFS4_MAX_SESSIONID_LEN + 20); 256 257 WRITE32(OP_CB_SEQUENCE); 258 WRITEMEM(args->cbs_clp->cl_sessionid.data, NFS4_MAX_SESSIONID_LEN); 259 WRITE32(args->cbs_clp->cl_cb_seq_nr); 260 WRITE32(0); /* slotid, always 0 */ 261 WRITE32(0); /* highest slotid always 0 */ 262 WRITE32(0); /* cachethis always 0 */ 263 WRITE32(0); /* FIXME: support referring_call_lists */ 264 hdr->nops++; 265 } 266 267 static int 268 nfs4_xdr_enc_cb_null(struct rpc_rqst *req, __be32 *p) 269 { 270 struct xdr_stream xdrs, *xdr = &xdrs; 271 272 xdr_init_encode(&xdrs, &req->rq_snd_buf, p); 273 RESERVE_SPACE(0); 274 return 0; 275 } 276 277 static int 278 nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, __be32 *p, 279 struct nfs4_rpc_args *rpc_args) 280 { 281 struct xdr_stream xdr; 282 struct nfs4_delegation *args = rpc_args->args_op; 283 struct nfs4_cb_compound_hdr hdr = { 284 .ident = args->dl_ident, 285 .minorversion = rpc_args->args_seq.cbs_minorversion, 286 }; 287 288 xdr_init_encode(&xdr, &req->rq_snd_buf, p); 289 encode_cb_compound_hdr(&xdr, &hdr); 290 encode_cb_sequence(&xdr, &rpc_args->args_seq, &hdr); 291 encode_cb_recall(&xdr, args, &hdr); 292 encode_cb_nops(&hdr); 293 return 0; 294 } 295 296 297 static int 298 decode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr){ 299 __be32 *p; 300 301 READ_BUF(8); 302 READ32(hdr->status); 303 READ32(hdr->taglen); 304 READ_BUF(hdr->taglen + 4); 305 hdr->tag = (char *)p; 306 p += XDR_QUADLEN(hdr->taglen); 307 READ32(hdr->nops); 308 return 0; 309 } 310 311 static int 312 decode_cb_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected) 313 { 314 __be32 *p; 315 u32 op; 316 int32_t nfserr; 317 318 READ_BUF(8); 319 READ32(op); 320 if (op != expected) { 321 dprintk("NFSD: decode_cb_op_hdr: Callback server returned " 322 " operation %d but we issued a request for %d\n", 323 op, expected); 324 return -EIO; 325 } 326 READ32(nfserr); 327 if (nfserr != NFS_OK) 328 return -nfs_cb_stat_to_errno(nfserr); 329 return 0; 330 } 331 332 /* 333 * Our current back channel implmentation supports a single backchannel 334 * with a single slot. 335 */ 336 static int 337 decode_cb_sequence(struct xdr_stream *xdr, struct nfsd4_cb_sequence *res, 338 struct rpc_rqst *rqstp) 339 { 340 struct nfs4_sessionid id; 341 int status; 342 u32 dummy; 343 __be32 *p; 344 345 if (res->cbs_minorversion == 0) 346 return 0; 347 348 status = decode_cb_op_hdr(xdr, OP_CB_SEQUENCE); 349 if (status) 350 return status; 351 352 /* 353 * If the server returns different values for sessionID, slotID or 354 * sequence number, the server is looney tunes. 355 */ 356 status = -ESERVERFAULT; 357 358 READ_BUF(NFS4_MAX_SESSIONID_LEN + 16); 359 memcpy(id.data, p, NFS4_MAX_SESSIONID_LEN); 360 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN); 361 if (memcmp(id.data, res->cbs_clp->cl_sessionid.data, 362 NFS4_MAX_SESSIONID_LEN)) { 363 dprintk("%s Invalid session id\n", __func__); 364 goto out; 365 } 366 READ32(dummy); 367 if (dummy != res->cbs_clp->cl_cb_seq_nr) { 368 dprintk("%s Invalid sequence number\n", __func__); 369 goto out; 370 } 371 READ32(dummy); /* slotid must be 0 */ 372 if (dummy != 0) { 373 dprintk("%s Invalid slotid\n", __func__); 374 goto out; 375 } 376 /* FIXME: process highest slotid and target highest slotid */ 377 status = 0; 378 out: 379 return status; 380 } 381 382 383 static int 384 nfs4_xdr_dec_cb_null(struct rpc_rqst *req, __be32 *p) 385 { 386 return 0; 387 } 388 389 static int 390 nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, __be32 *p, 391 struct nfsd4_cb_sequence *seq) 392 { 393 struct xdr_stream xdr; 394 struct nfs4_cb_compound_hdr hdr; 395 int status; 396 397 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p); 398 status = decode_cb_compound_hdr(&xdr, &hdr); 399 if (status) 400 goto out; 401 if (seq) { 402 status = decode_cb_sequence(&xdr, seq, rqstp); 403 if (status) 404 goto out; 405 } 406 status = decode_cb_op_hdr(&xdr, OP_CB_RECALL); 407 out: 408 return status; 409 } 410 411 /* 412 * RPC procedure tables 413 */ 414 #define PROC(proc, call, argtype, restype) \ 415 [NFSPROC4_CLNT_##proc] = { \ 416 .p_proc = NFSPROC4_CB_##call, \ 417 .p_encode = (kxdrproc_t) nfs4_xdr_##argtype, \ 418 .p_decode = (kxdrproc_t) nfs4_xdr_##restype, \ 419 .p_arglen = NFS4_##argtype##_sz, \ 420 .p_replen = NFS4_##restype##_sz, \ 421 .p_statidx = NFSPROC4_CB_##call, \ 422 .p_name = #proc, \ 423 } 424 425 static struct rpc_procinfo nfs4_cb_procedures[] = { 426 PROC(CB_NULL, NULL, enc_cb_null, dec_cb_null), 427 PROC(CB_RECALL, COMPOUND, enc_cb_recall, dec_cb_recall), 428 }; 429 430 static struct rpc_version nfs_cb_version4 = { 431 .number = 1, 432 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), 433 .procs = nfs4_cb_procedures 434 }; 435 436 static struct rpc_version * nfs_cb_version[] = { 437 NULL, 438 &nfs_cb_version4, 439 }; 440 441 static struct rpc_program cb_program; 442 443 static struct rpc_stat cb_stats = { 444 .program = &cb_program 445 }; 446 447 #define NFS4_CALLBACK 0x40000000 448 static struct rpc_program cb_program = { 449 .name = "nfs4_cb", 450 .number = NFS4_CALLBACK, 451 .nrvers = ARRAY_SIZE(nfs_cb_version), 452 .version = nfs_cb_version, 453 .stats = &cb_stats, 454 .pipe_dir_name = "/nfsd4_cb", 455 }; 456 457 static int max_cb_time(void) 458 { 459 return max(NFSD_LEASE_TIME/10, (time_t)1) * HZ; 460 } 461 462 /* Reference counting, callback cleanup, etc., all look racy as heck. 463 * And why is cb_set an atomic? */ 464 465 int setup_callback_client(struct nfs4_client *clp) 466 { 467 struct nfs4_cb_conn *cb = &clp->cl_cb_conn; 468 struct rpc_timeout timeparms = { 469 .to_initval = max_cb_time(), 470 .to_retries = 0, 471 }; 472 struct rpc_create_args args = { 473 .protocol = XPRT_TRANSPORT_TCP, 474 .address = (struct sockaddr *) &cb->cb_addr, 475 .addrsize = cb->cb_addrlen, 476 .timeout = &timeparms, 477 .program = &cb_program, 478 .prognumber = cb->cb_prog, 479 .version = nfs_cb_version[1]->number, 480 .authflavor = clp->cl_flavor, 481 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), 482 .client_name = clp->cl_principal, 483 }; 484 struct rpc_clnt *client; 485 486 if (!clp->cl_principal && (clp->cl_flavor >= RPC_AUTH_GSS_KRB5)) 487 return -EINVAL; 488 if (cb->cb_minorversion) { 489 args.bc_xprt = clp->cl_cb_xprt; 490 args.protocol = XPRT_TRANSPORT_BC_TCP; 491 } 492 /* Create RPC client */ 493 client = rpc_create(&args); 494 if (IS_ERR(client)) { 495 dprintk("NFSD: couldn't create callback client: %ld\n", 496 PTR_ERR(client)); 497 return PTR_ERR(client); 498 } 499 cb->cb_client = client; 500 return 0; 501 502 } 503 504 static void warn_no_callback_path(struct nfs4_client *clp, int reason) 505 { 506 dprintk("NFSD: warning: no callback path to client %.*s: error %d\n", 507 (int)clp->cl_name.len, clp->cl_name.data, reason); 508 } 509 510 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata) 511 { 512 struct nfs4_client *clp = calldata; 513 514 if (task->tk_status) 515 warn_no_callback_path(clp, task->tk_status); 516 else 517 atomic_set(&clp->cl_cb_conn.cb_set, 1); 518 put_nfs4_client(clp); 519 } 520 521 static const struct rpc_call_ops nfsd4_cb_probe_ops = { 522 .rpc_call_done = nfsd4_cb_probe_done, 523 }; 524 525 static struct rpc_cred *callback_cred; 526 527 int set_callback_cred(void) 528 { 529 if (callback_cred) 530 return 0; 531 callback_cred = rpc_lookup_machine_cred(); 532 if (!callback_cred) 533 return -ENOMEM; 534 return 0; 535 } 536 537 538 void do_probe_callback(struct nfs4_client *clp) 539 { 540 struct nfs4_cb_conn *cb = &clp->cl_cb_conn; 541 struct rpc_message msg = { 542 .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL], 543 .rpc_argp = clp, 544 .rpc_cred = callback_cred 545 }; 546 int status; 547 548 status = rpc_call_async(cb->cb_client, &msg, 549 RPC_TASK_SOFT | RPC_TASK_SOFTCONN, 550 &nfsd4_cb_probe_ops, (void *)clp); 551 if (status) { 552 warn_no_callback_path(clp, status); 553 put_nfs4_client(clp); 554 } 555 } 556 557 /* 558 * Set up the callback client and put a NFSPROC4_CB_NULL on the wire... 559 */ 560 void 561 nfsd4_probe_callback(struct nfs4_client *clp) 562 { 563 int status; 564 565 BUG_ON(atomic_read(&clp->cl_cb_conn.cb_set)); 566 567 status = setup_callback_client(clp); 568 if (status) { 569 warn_no_callback_path(clp, status); 570 return; 571 } 572 573 /* the task holds a reference to the nfs4_client struct */ 574 atomic_inc(&clp->cl_count); 575 576 do_probe_callback(clp); 577 } 578 579 /* 580 * There's currently a single callback channel slot. 581 * If the slot is available, then mark it busy. Otherwise, set the 582 * thread for sleeping on the callback RPC wait queue. 583 */ 584 static int nfsd41_cb_setup_sequence(struct nfs4_client *clp, 585 struct rpc_task *task) 586 { 587 struct nfs4_rpc_args *args = task->tk_msg.rpc_argp; 588 u32 *ptr = (u32 *)clp->cl_sessionid.data; 589 int status = 0; 590 591 dprintk("%s: %u:%u:%u:%u\n", __func__, 592 ptr[0], ptr[1], ptr[2], ptr[3]); 593 594 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) { 595 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL); 596 dprintk("%s slot is busy\n", __func__); 597 status = -EAGAIN; 598 goto out; 599 } 600 601 /* 602 * We'll need the clp during XDR encoding and decoding, 603 * and the sequence during decoding to verify the reply 604 */ 605 args->args_seq.cbs_clp = clp; 606 task->tk_msg.rpc_resp = &args->args_seq; 607 608 out: 609 dprintk("%s status=%d\n", __func__, status); 610 return status; 611 } 612 613 /* 614 * TODO: cb_sequence should support referring call lists, cachethis, multiple 615 * slots, and mark callback channel down on communication errors. 616 */ 617 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata) 618 { 619 struct nfs4_delegation *dp = calldata; 620 struct nfs4_client *clp = dp->dl_client; 621 struct nfs4_rpc_args *args = task->tk_msg.rpc_argp; 622 u32 minorversion = clp->cl_cb_conn.cb_minorversion; 623 int status = 0; 624 625 args->args_seq.cbs_minorversion = minorversion; 626 if (minorversion) { 627 status = nfsd41_cb_setup_sequence(clp, task); 628 if (status) { 629 if (status != -EAGAIN) { 630 /* terminate rpc task */ 631 task->tk_status = status; 632 task->tk_action = NULL; 633 } 634 return; 635 } 636 } 637 rpc_call_start(task); 638 } 639 640 static void nfsd4_cb_done(struct rpc_task *task, void *calldata) 641 { 642 struct nfs4_delegation *dp = calldata; 643 struct nfs4_client *clp = dp->dl_client; 644 645 dprintk("%s: minorversion=%d\n", __func__, 646 clp->cl_cb_conn.cb_minorversion); 647 648 if (clp->cl_cb_conn.cb_minorversion) { 649 /* No need for lock, access serialized in nfsd4_cb_prepare */ 650 ++clp->cl_cb_seq_nr; 651 clear_bit(0, &clp->cl_cb_slot_busy); 652 rpc_wake_up_next(&clp->cl_cb_waitq); 653 dprintk("%s: freed slot, new seqid=%d\n", __func__, 654 clp->cl_cb_seq_nr); 655 656 /* We're done looking into the sequence information */ 657 task->tk_msg.rpc_resp = NULL; 658 } 659 } 660 661 static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata) 662 { 663 struct nfs4_delegation *dp = calldata; 664 struct nfs4_client *clp = dp->dl_client; 665 666 nfsd4_cb_done(task, calldata); 667 668 switch (task->tk_status) { 669 case -EIO: 670 /* Network partition? */ 671 atomic_set(&clp->cl_cb_conn.cb_set, 0); 672 warn_no_callback_path(clp, task->tk_status); 673 case -EBADHANDLE: 674 case -NFS4ERR_BAD_STATEID: 675 /* Race: client probably got cb_recall 676 * before open reply granting delegation */ 677 break; 678 default: 679 /* success, or error we can't handle */ 680 goto done; 681 } 682 if (dp->dl_retries--) { 683 rpc_delay(task, 2*HZ); 684 task->tk_status = 0; 685 rpc_restart_call(task); 686 return; 687 } else { 688 atomic_set(&clp->cl_cb_conn.cb_set, 0); 689 warn_no_callback_path(clp, task->tk_status); 690 } 691 done: 692 kfree(task->tk_msg.rpc_argp); 693 } 694 695 static void nfsd4_cb_recall_release(void *calldata) 696 { 697 struct nfs4_delegation *dp = calldata; 698 struct nfs4_client *clp = dp->dl_client; 699 700 nfs4_put_delegation(dp); 701 put_nfs4_client(clp); 702 } 703 704 static const struct rpc_call_ops nfsd4_cb_recall_ops = { 705 .rpc_call_prepare = nfsd4_cb_prepare, 706 .rpc_call_done = nfsd4_cb_recall_done, 707 .rpc_release = nfsd4_cb_recall_release, 708 }; 709 710 /* 711 * called with dp->dl_count inc'ed. 712 */ 713 void 714 nfsd4_cb_recall(struct nfs4_delegation *dp) 715 { 716 struct nfs4_client *clp = dp->dl_client; 717 struct rpc_clnt *clnt = clp->cl_cb_conn.cb_client; 718 struct nfs4_rpc_args *args; 719 struct rpc_message msg = { 720 .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL], 721 .rpc_cred = callback_cred 722 }; 723 int status = -ENOMEM; 724 725 args = kzalloc(sizeof(*args), GFP_KERNEL); 726 if (!args) 727 goto out; 728 args->args_op = dp; 729 msg.rpc_argp = args; 730 dp->dl_retries = 1; 731 status = rpc_call_async(clnt, &msg, RPC_TASK_SOFT, 732 &nfsd4_cb_recall_ops, dp); 733 out: 734 if (status) { 735 kfree(args); 736 put_nfs4_client(clp); 737 nfs4_put_delegation(dp); 738 } 739 } 740