1 /*- 2 * Copyright (c) 2012 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Edward Tomasz Napierala under sponsorship 6 * from the FreeBSD Foundation. 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 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 /* 33 * iSCSI Common Layer. It's used by both the initiator and target to send 34 * and receive iSCSI PDUs. 35 */ 36 37 #include <sys/param.h> 38 #include <sys/capability.h> 39 #include <sys/condvar.h> 40 #include <sys/conf.h> 41 #include <sys/file.h> 42 #include <sys/kernel.h> 43 #include <sys/kthread.h> 44 #include <sys/lock.h> 45 #include <sys/mbuf.h> 46 #include <sys/mutex.h> 47 #include <sys/module.h> 48 #include <sys/socket.h> 49 #include <sys/socketvar.h> 50 #include <sys/sysctl.h> 51 #include <sys/systm.h> 52 #include <sys/sx.h> 53 #include <sys/uio.h> 54 #include <vm/uma.h> 55 #include <netinet/in.h> 56 #include <netinet/tcp.h> 57 58 #include "icl.h" 59 #include "iscsi_proto.h" 60 61 SYSCTL_NODE(_kern, OID_AUTO, icl, CTLFLAG_RD, 0, "iSCSI Common Layer"); 62 static int debug = 1; 63 TUNABLE_INT("kern.icl.debug", &debug); 64 SYSCTL_INT(_kern_icl, OID_AUTO, debug, CTLFLAG_RW, 65 &debug, 1, "Enable debug messages"); 66 static int partial_receive_len = 1 * 1024; /* XXX: More? */ 67 TUNABLE_INT("kern.icl.partial_receive_len", &partial_receive_len); 68 SYSCTL_INT(_kern_icl, OID_AUTO, partial_receive_len, CTLFLAG_RW, 69 &partial_receive_len, 1 * 1024, "Minimum read size for partially received " 70 "data segment"); 71 72 static uma_zone_t icl_conn_zone; 73 static uma_zone_t icl_pdu_zone; 74 75 static volatile u_int icl_ncons; 76 77 #define ICL_DEBUG(X, ...) \ 78 if (debug > 1) { \ 79 printf("%s: " X "\n", __func__, ## __VA_ARGS__);\ 80 } while (0) 81 82 #define ICL_WARN(X, ...) \ 83 if (debug > 0) { \ 84 printf("WARNING: %s: " X "\n", \ 85 __func__, ## __VA_ARGS__); \ 86 } while (0) 87 88 #define ICL_CONN_LOCK(X) mtx_lock(&X->ic_lock) 89 #define ICL_CONN_UNLOCK(X) mtx_unlock(&X->ic_lock) 90 #define ICL_CONN_LOCK_ASSERT(X) mtx_assert(&X->ic_lock, MA_OWNED) 91 92 static void 93 icl_conn_fail(struct icl_conn *ic) 94 { 95 if (ic->ic_socket == NULL) 96 return; 97 98 /* 99 * XXX 100 */ 101 ic->ic_socket->so_error = EDOOFUS; 102 (ic->ic_error)(ic); 103 } 104 105 static struct mbuf * 106 icl_conn_receive(struct icl_conn *ic, size_t len) 107 { 108 struct uio uio; 109 struct socket *so; 110 struct mbuf *m; 111 int error, flags; 112 113 so = ic->ic_socket; 114 115 memset(&uio, 0, sizeof(uio)); 116 uio.uio_resid = len; 117 118 flags = MSG_DONTWAIT; 119 error = soreceive(so, NULL, &uio, &m, NULL, &flags); 120 if (error != 0) { 121 ICL_DEBUG("soreceive error %d", error); 122 return (NULL); 123 } 124 if (uio.uio_resid != 0) { 125 m_freem(m); 126 ICL_DEBUG("short read"); 127 return (NULL); 128 } 129 130 return (m); 131 } 132 133 static struct icl_pdu * 134 icl_pdu_new(struct icl_conn *ic, int flags) 135 { 136 struct icl_pdu *ip; 137 138 refcount_acquire(&ic->ic_outstanding_pdus); 139 ip = uma_zalloc(icl_pdu_zone, flags | M_ZERO); 140 if (ip == NULL) { 141 ICL_WARN("failed to allocate %zd bytes", sizeof(*ip)); 142 refcount_release(&ic->ic_outstanding_pdus); 143 return (NULL); 144 } 145 146 ip->ip_conn = ic; 147 148 return (ip); 149 } 150 151 void 152 icl_pdu_free(struct icl_pdu *ip) 153 { 154 struct icl_conn *ic; 155 156 ic = ip->ip_conn; 157 158 m_freem(ip->ip_bhs_mbuf); 159 m_freem(ip->ip_ahs_mbuf); 160 m_freem(ip->ip_data_mbuf); 161 uma_zfree(icl_pdu_zone, ip); 162 refcount_release(&ic->ic_outstanding_pdus); 163 } 164 165 /* 166 * Allocate icl_pdu with empty BHS to fill up by the caller. 167 */ 168 struct icl_pdu * 169 icl_pdu_new_bhs(struct icl_conn *ic, int flags) 170 { 171 struct icl_pdu *ip; 172 173 ip = icl_pdu_new(ic, flags); 174 if (ip == NULL) 175 return (NULL); 176 177 ip->ip_bhs_mbuf = m_getm2(NULL, sizeof(struct iscsi_bhs), 178 flags, MT_DATA, M_PKTHDR); 179 if (ip->ip_bhs_mbuf == NULL) { 180 ICL_WARN("failed to allocate %zd bytes", sizeof(*ip)); 181 icl_pdu_free(ip); 182 return (NULL); 183 } 184 ip->ip_bhs = mtod(ip->ip_bhs_mbuf, struct iscsi_bhs *); 185 memset(ip->ip_bhs, 0, sizeof(struct iscsi_bhs)); 186 ip->ip_bhs_mbuf->m_len = sizeof(struct iscsi_bhs); 187 188 return (ip); 189 } 190 191 static int 192 icl_pdu_ahs_length(const struct icl_pdu *request) 193 { 194 195 return (request->ip_bhs->bhs_total_ahs_len * 4); 196 } 197 198 size_t 199 icl_pdu_data_segment_length(const struct icl_pdu *request) 200 { 201 uint32_t len = 0; 202 203 len += request->ip_bhs->bhs_data_segment_len[0]; 204 len <<= 8; 205 len += request->ip_bhs->bhs_data_segment_len[1]; 206 len <<= 8; 207 len += request->ip_bhs->bhs_data_segment_len[2]; 208 209 return (len); 210 } 211 212 static void 213 icl_pdu_set_data_segment_length(struct icl_pdu *response, uint32_t len) 214 { 215 216 response->ip_bhs->bhs_data_segment_len[2] = len; 217 response->ip_bhs->bhs_data_segment_len[1] = len >> 8; 218 response->ip_bhs->bhs_data_segment_len[0] = len >> 16; 219 } 220 221 static size_t 222 icl_pdu_padding(const struct icl_pdu *ip) 223 { 224 225 if ((ip->ip_data_len % 4) != 0) 226 return (4 - (ip->ip_data_len % 4)); 227 228 return (0); 229 } 230 231 static size_t 232 icl_pdu_size(const struct icl_pdu *response) 233 { 234 size_t len; 235 236 KASSERT(response->ip_ahs_len == 0, ("responding with AHS")); 237 238 len = sizeof(struct iscsi_bhs) + response->ip_data_len + 239 icl_pdu_padding(response); 240 if (response->ip_conn->ic_header_crc32c) 241 len += ISCSI_HEADER_DIGEST_SIZE; 242 if (response->ip_data_len != 0 && response->ip_conn->ic_data_crc32c) 243 len += ISCSI_DATA_DIGEST_SIZE; 244 245 return (len); 246 } 247 248 static int 249 icl_pdu_receive_bhs(struct icl_pdu *request, size_t *availablep) 250 { 251 struct mbuf *m; 252 253 m = icl_conn_receive(request->ip_conn, sizeof(struct iscsi_bhs)); 254 if (m == NULL) { 255 ICL_DEBUG("failed to receive BHS"); 256 return (-1); 257 } 258 259 request->ip_bhs_mbuf = m_pullup(m, sizeof(struct iscsi_bhs)); 260 if (request->ip_bhs_mbuf == NULL) { 261 ICL_WARN("m_pullup failed"); 262 return (-1); 263 } 264 request->ip_bhs = mtod(request->ip_bhs_mbuf, struct iscsi_bhs *); 265 266 /* 267 * XXX: For architectures with strict alignment requirements 268 * we may need to allocate ip_bhs and copy the data into it. 269 * For some reason, though, not doing this doesn't seem 270 * to cause problems; tested on sparc64. 271 */ 272 273 *availablep -= sizeof(struct iscsi_bhs); 274 return (0); 275 } 276 277 static int 278 icl_pdu_receive_ahs(struct icl_pdu *request, size_t *availablep) 279 { 280 281 request->ip_ahs_len = icl_pdu_ahs_length(request); 282 if (request->ip_ahs_len == 0) 283 return (0); 284 285 request->ip_ahs_mbuf = icl_conn_receive(request->ip_conn, 286 request->ip_ahs_len); 287 if (request->ip_ahs_mbuf == NULL) { 288 ICL_DEBUG("failed to receive AHS"); 289 return (-1); 290 } 291 292 *availablep -= request->ip_ahs_len; 293 return (0); 294 } 295 296 static uint32_t 297 icl_mbuf_to_crc32c(const struct mbuf *m0) 298 { 299 uint32_t digest = 0xffffffff; 300 const struct mbuf *m; 301 302 for (m = m0; m != NULL; m = m->m_next) 303 digest = calculate_crc32c(digest, 304 mtod(m, const void *), m->m_len); 305 306 digest = digest ^ 0xffffffff; 307 308 return (digest); 309 } 310 311 static int 312 icl_pdu_check_header_digest(struct icl_pdu *request, size_t *availablep) 313 { 314 struct mbuf *m; 315 uint32_t received_digest, valid_digest; 316 317 if (request->ip_conn->ic_header_crc32c == false) 318 return (0); 319 320 m = icl_conn_receive(request->ip_conn, ISCSI_HEADER_DIGEST_SIZE); 321 if (m == NULL) { 322 ICL_DEBUG("failed to receive header digest"); 323 return (-1); 324 } 325 326 CTASSERT(sizeof(received_digest) == ISCSI_HEADER_DIGEST_SIZE); 327 m_copydata(m, 0, ISCSI_HEADER_DIGEST_SIZE, (void *)&received_digest); 328 m_freem(m); 329 330 *availablep -= ISCSI_HEADER_DIGEST_SIZE; 331 332 /* 333 * XXX: Handle AHS. 334 */ 335 valid_digest = icl_mbuf_to_crc32c(request->ip_bhs_mbuf); 336 if (received_digest != valid_digest) { 337 ICL_WARN("header digest check failed; got 0x%x, " 338 "should be 0x%x", received_digest, valid_digest); 339 return (-1); 340 } 341 342 return (0); 343 } 344 345 /* 346 * Return the number of bytes that should be waiting in the receive socket 347 * before icl_pdu_receive_data_segment() gets called. 348 */ 349 static size_t 350 icl_pdu_data_segment_receive_len(const struct icl_pdu *request) 351 { 352 size_t len; 353 354 len = icl_pdu_data_segment_length(request); 355 if (len == 0) 356 return (0); 357 358 /* 359 * Account for the parts of data segment already read from 360 * the socket buffer. 361 */ 362 KASSERT(len > request->ip_data_len, ("len <= request->ip_data_len")); 363 len -= request->ip_data_len; 364 365 /* 366 * Don't always wait for the full data segment to be delivered 367 * to the socket; this might badly affect performance due to 368 * TCP window scaling. 369 */ 370 if (len > partial_receive_len) { 371 #if 0 372 ICL_DEBUG("need %zd bytes of data, limiting to %zd", 373 len, partial_receive_len)); 374 #endif 375 len = partial_receive_len; 376 377 return (len); 378 } 379 380 /* 381 * Account for padding. Note that due to the way code is written, 382 * the icl_pdu_receive_data_segment() must always receive padding 383 * along with the last part of data segment, because it would be 384 * impossible to tell whether we've already received the full data 385 * segment including padding, or without it. 386 */ 387 if ((len % 4) != 0) 388 len += 4 - (len % 4); 389 390 #if 0 391 ICL_DEBUG("need %zd bytes of data", len)); 392 #endif 393 394 return (len); 395 } 396 397 static int 398 icl_pdu_receive_data_segment(struct icl_pdu *request, 399 size_t *availablep, bool *more_neededp) 400 { 401 struct icl_conn *ic; 402 size_t len, padding = 0; 403 struct mbuf *m; 404 405 ic = request->ip_conn; 406 407 *more_neededp = false; 408 ic->ic_receive_len = 0; 409 410 len = icl_pdu_data_segment_length(request); 411 if (len == 0) 412 return (0); 413 414 if ((len % 4) != 0) 415 padding = 4 - (len % 4); 416 417 /* 418 * Account for already received parts of data segment. 419 */ 420 KASSERT(len > request->ip_data_len, ("len <= request->ip_data_len")); 421 len -= request->ip_data_len; 422 423 if (len + padding > *availablep) { 424 /* 425 * Not enough data in the socket buffer. Receive as much 426 * as we can. Don't receive padding, since, obviously, it's 427 * not the end of data segment yet. 428 */ 429 #if 0 430 ICL_DEBUG("limited from %zd to %zd", 431 len + padding, *availablep - padding)); 432 #endif 433 len = *availablep - padding; 434 *more_neededp = true; 435 padding = 0; 436 } 437 438 /* 439 * Must not try to receive padding without at least one byte 440 * of actual data segment. 441 */ 442 if (len > 0) { 443 m = icl_conn_receive(request->ip_conn, len + padding); 444 if (m == NULL) { 445 ICL_DEBUG("failed to receive data segment"); 446 return (-1); 447 } 448 449 if (request->ip_data_mbuf == NULL) 450 request->ip_data_mbuf = m; 451 else 452 m_cat(request->ip_data_mbuf, m); 453 454 request->ip_data_len += len; 455 *availablep -= len + padding; 456 } else 457 ICL_DEBUG("len 0"); 458 459 if (*more_neededp) 460 ic->ic_receive_len = 461 icl_pdu_data_segment_receive_len(request); 462 463 return (0); 464 } 465 466 static int 467 icl_pdu_check_data_digest(struct icl_pdu *request, size_t *availablep) 468 { 469 struct mbuf *m; 470 uint32_t received_digest, valid_digest; 471 472 if (request->ip_conn->ic_data_crc32c == false) 473 return (0); 474 475 if (request->ip_data_len == 0) 476 return (0); 477 478 m = icl_conn_receive(request->ip_conn, ISCSI_DATA_DIGEST_SIZE); 479 if (m == NULL) { 480 ICL_DEBUG("failed to receive data digest"); 481 return (-1); 482 } 483 484 CTASSERT(sizeof(received_digest) == ISCSI_DATA_DIGEST_SIZE); 485 m_copydata(m, 0, ISCSI_DATA_DIGEST_SIZE, (void *)&received_digest); 486 m_freem(m); 487 488 *availablep -= ISCSI_DATA_DIGEST_SIZE; 489 490 /* 491 * Note that ip_data_mbuf also contains padding; since digest 492 * calculation is supposed to include that, we iterate over 493 * the entire ip_data_mbuf chain, not just ip_data_len bytes of it. 494 */ 495 valid_digest = icl_mbuf_to_crc32c(request->ip_data_mbuf); 496 if (received_digest != valid_digest) { 497 ICL_WARN("data digest check failed; got 0x%x, " 498 "should be 0x%x", received_digest, valid_digest); 499 return (-1); 500 } 501 502 return (0); 503 } 504 505 /* 506 * Somewhat contrary to the name, this attempts to receive only one 507 * "part" of PDU at a time; call it repeatedly until it returns non-NULL. 508 */ 509 static struct icl_pdu * 510 icl_conn_receive_pdu(struct icl_conn *ic, size_t *availablep) 511 { 512 struct icl_pdu *request; 513 struct socket *so; 514 size_t len; 515 int error; 516 bool more_needed; 517 518 so = ic->ic_socket; 519 520 if (ic->ic_receive_state == ICL_CONN_STATE_BHS) { 521 KASSERT(ic->ic_receive_pdu == NULL, 522 ("ic->ic_receive_pdu != NULL")); 523 request = icl_pdu_new(ic, M_NOWAIT); 524 if (request == NULL) { 525 ICL_DEBUG("failed to allocate PDU; " 526 "dropping connection"); 527 icl_conn_fail(ic); 528 return (NULL); 529 } 530 ic->ic_receive_pdu = request; 531 } else { 532 KASSERT(ic->ic_receive_pdu != NULL, 533 ("ic->ic_receive_pdu == NULL")); 534 request = ic->ic_receive_pdu; 535 } 536 537 if (*availablep < ic->ic_receive_len) { 538 #if 0 539 ICL_DEBUG("not enough data; need %zd, " 540 "have %zd", ic->ic_receive_len, *availablep); 541 #endif 542 return (NULL); 543 } 544 545 switch (ic->ic_receive_state) { 546 case ICL_CONN_STATE_BHS: 547 //ICL_DEBUG("receiving BHS"); 548 error = icl_pdu_receive_bhs(request, availablep); 549 if (error != 0) { 550 ICL_DEBUG("failed to receive BHS; " 551 "dropping connection"); 552 break; 553 } 554 555 /* 556 * We don't enforce any limit for AHS length; 557 * its length is stored in 8 bit field. 558 */ 559 560 len = icl_pdu_data_segment_length(request); 561 if (len > ic->ic_max_data_segment_length) { 562 ICL_WARN("received data segment " 563 "length %zd is larger than negotiated " 564 "MaxDataSegmentLength %zd; " 565 "dropping connection", 566 len, ic->ic_max_data_segment_length); 567 error = EINVAL; 568 break; 569 } 570 571 ic->ic_receive_state = ICL_CONN_STATE_AHS; 572 ic->ic_receive_len = icl_pdu_ahs_length(request); 573 break; 574 575 case ICL_CONN_STATE_AHS: 576 //ICL_DEBUG("receiving AHS"); 577 error = icl_pdu_receive_ahs(request, availablep); 578 if (error != 0) { 579 ICL_DEBUG("failed to receive AHS; " 580 "dropping connection"); 581 break; 582 } 583 ic->ic_receive_state = ICL_CONN_STATE_HEADER_DIGEST; 584 if (ic->ic_header_crc32c == false) 585 ic->ic_receive_len = 0; 586 else 587 ic->ic_receive_len = ISCSI_HEADER_DIGEST_SIZE; 588 break; 589 590 case ICL_CONN_STATE_HEADER_DIGEST: 591 //ICL_DEBUG("receiving header digest"); 592 error = icl_pdu_check_header_digest(request, availablep); 593 if (error != 0) { 594 ICL_DEBUG("header digest failed; " 595 "dropping connection"); 596 break; 597 } 598 599 ic->ic_receive_state = ICL_CONN_STATE_DATA; 600 ic->ic_receive_len = 601 icl_pdu_data_segment_receive_len(request); 602 break; 603 604 case ICL_CONN_STATE_DATA: 605 //ICL_DEBUG("receiving data segment"); 606 error = icl_pdu_receive_data_segment(request, availablep, 607 &more_needed); 608 if (error != 0) { 609 ICL_DEBUG("failed to receive data segment;" 610 "dropping connection"); 611 break; 612 } 613 614 if (more_needed) 615 break; 616 617 ic->ic_receive_state = ICL_CONN_STATE_DATA_DIGEST; 618 if (request->ip_data_len == 0 || ic->ic_data_crc32c == false) 619 ic->ic_receive_len = 0; 620 else 621 ic->ic_receive_len = ISCSI_DATA_DIGEST_SIZE; 622 break; 623 624 case ICL_CONN_STATE_DATA_DIGEST: 625 //ICL_DEBUG("receiving data digest"); 626 error = icl_pdu_check_data_digest(request, availablep); 627 if (error != 0) { 628 ICL_DEBUG("data digest failed; " 629 "dropping connection"); 630 break; 631 } 632 633 /* 634 * We've received complete PDU; reset the receive state machine 635 * and return the PDU. 636 */ 637 ic->ic_receive_state = ICL_CONN_STATE_BHS; 638 ic->ic_receive_len = sizeof(struct iscsi_bhs); 639 ic->ic_receive_pdu = NULL; 640 return (request); 641 642 default: 643 panic("invalid ic_receive_state %d\n", ic->ic_receive_state); 644 } 645 646 if (error != 0) { 647 icl_pdu_free(request); 648 icl_conn_fail(ic); 649 } 650 651 return (NULL); 652 } 653 654 static void 655 icl_conn_receive_pdus(struct icl_conn *ic, size_t available) 656 { 657 struct icl_pdu *response; 658 struct socket *so; 659 660 so = ic->ic_socket; 661 662 /* 663 * This can never happen; we're careful to only mess with ic->ic_socket 664 * pointer when the send/receive threads are not running. 665 */ 666 KASSERT(so != NULL, ("NULL socket")); 667 668 for (;;) { 669 if (ic->ic_disconnecting) 670 return; 671 672 if (so->so_error != 0) { 673 ICL_DEBUG("connection error %d; " 674 "dropping connection", so->so_error); 675 icl_conn_fail(ic); 676 return; 677 } 678 679 /* 680 * Loop until we have a complete PDU or there is not enough 681 * data in the socket buffer. 682 */ 683 if (available < ic->ic_receive_len) { 684 #if 0 685 ICL_DEBUG("not enough data; have %zd, " 686 "need %zd", available, 687 ic->ic_receive_len); 688 #endif 689 return; 690 } 691 692 response = icl_conn_receive_pdu(ic, &available); 693 if (response == NULL) 694 continue; 695 696 if (response->ip_ahs_len > 0) { 697 ICL_WARN("received PDU with unsupported " 698 "AHS; opcode 0x%x; dropping connection", 699 response->ip_bhs->bhs_opcode); 700 icl_pdu_free(response); 701 icl_conn_fail(ic); 702 return; 703 } 704 705 (ic->ic_receive)(response); 706 } 707 } 708 709 static void 710 icl_receive_thread(void *arg) 711 { 712 struct icl_conn *ic; 713 size_t available; 714 struct socket *so; 715 716 ic = arg; 717 so = ic->ic_socket; 718 719 ICL_CONN_LOCK(ic); 720 ic->ic_receive_running = true; 721 ICL_CONN_UNLOCK(ic); 722 723 for (;;) { 724 if (ic->ic_disconnecting) { 725 //ICL_DEBUG("terminating"); 726 break; 727 } 728 729 SOCKBUF_LOCK(&so->so_rcv); 730 available = so->so_rcv.sb_cc; 731 if (available < ic->ic_receive_len) { 732 so->so_rcv.sb_lowat = ic->ic_receive_len; 733 cv_wait(&ic->ic_receive_cv, &so->so_rcv.sb_mtx); 734 } 735 SOCKBUF_UNLOCK(&so->so_rcv); 736 737 icl_conn_receive_pdus(ic, available); 738 } 739 740 ICL_CONN_LOCK(ic); 741 ic->ic_receive_running = false; 742 ICL_CONN_UNLOCK(ic); 743 kthread_exit(); 744 } 745 746 static int 747 icl_soupcall_receive(struct socket *so, void *arg, int waitflag) 748 { 749 struct icl_conn *ic; 750 751 ic = arg; 752 cv_signal(&ic->ic_receive_cv); 753 return (SU_OK); 754 } 755 756 static int 757 icl_pdu_send(struct icl_pdu *request) 758 { 759 size_t padding, pdu_len; 760 uint32_t digest, zero = 0; 761 int error, ok; 762 struct socket *so; 763 struct icl_conn *ic; 764 765 ic = request->ip_conn; 766 so = request->ip_conn->ic_socket; 767 768 ICL_CONN_LOCK_ASSERT(ic); 769 770 icl_pdu_set_data_segment_length(request, request->ip_data_len); 771 772 pdu_len = icl_pdu_size(request); 773 774 if (ic->ic_header_crc32c) { 775 digest = icl_mbuf_to_crc32c(request->ip_bhs_mbuf); 776 ok = m_append(request->ip_bhs_mbuf, sizeof(digest), 777 (void *)&digest); 778 if (ok != 1) { 779 ICL_WARN("failed to append header digest"); 780 return (1); 781 } 782 } 783 784 if (request->ip_data_len != 0) { 785 padding = icl_pdu_padding(request); 786 if (padding > 0) { 787 ok = m_append(request->ip_data_mbuf, padding, 788 (void *)&zero); 789 if (ok != 1) { 790 ICL_WARN("failed to append padding"); 791 return (1); 792 } 793 } 794 795 if (ic->ic_data_crc32c) { 796 digest = icl_mbuf_to_crc32c(request->ip_data_mbuf); 797 798 ok = m_append(request->ip_data_mbuf, sizeof(digest), 799 (void *)&digest); 800 if (ok != 1) { 801 ICL_WARN("failed to append header digest"); 802 return (1); 803 } 804 } 805 806 m_cat(request->ip_bhs_mbuf, request->ip_data_mbuf); 807 request->ip_data_mbuf = NULL; 808 } 809 810 request->ip_bhs_mbuf->m_pkthdr.len = pdu_len; 811 812 error = sosend(so, NULL, NULL, request->ip_bhs_mbuf, 813 NULL, MSG_DONTWAIT, curthread); 814 request->ip_bhs_mbuf = NULL; /* Sosend consumes the mbuf. */ 815 if (error != 0) { 816 ICL_DEBUG("sosend error %d", error); 817 return (error); 818 } 819 820 return (0); 821 } 822 823 static void 824 icl_conn_send_pdus(struct icl_conn *ic) 825 { 826 struct icl_pdu *request; 827 struct socket *so; 828 size_t available, size; 829 int error; 830 831 ICL_CONN_LOCK_ASSERT(ic); 832 833 so = ic->ic_socket; 834 835 SOCKBUF_LOCK(&so->so_snd); 836 available = sbspace(&so->so_snd); 837 SOCKBUF_UNLOCK(&so->so_snd); 838 839 while (!TAILQ_EMPTY(&ic->ic_to_send)) { 840 if (ic->ic_disconnecting) 841 return; 842 843 request = TAILQ_FIRST(&ic->ic_to_send); 844 size = icl_pdu_size(request); 845 if (available < size) { 846 /* 847 * Set the low watermark on the socket, 848 * to avoid waking up until there is enough 849 * space. 850 */ 851 SOCKBUF_LOCK(&so->so_snd); 852 so->so_snd.sb_lowat = size; 853 SOCKBUF_UNLOCK(&so->so_snd); 854 #if 1 855 ICL_DEBUG("no space to send; " 856 "have %zd, need %zd", 857 available, size); 858 #endif 859 return; 860 } 861 available -= size; 862 TAILQ_REMOVE(&ic->ic_to_send, request, ip_next); 863 error = icl_pdu_send(request); 864 if (error != 0) { 865 ICL_DEBUG("failed to send PDU; " 866 "dropping connection"); 867 icl_conn_fail(ic); 868 return; 869 } 870 icl_pdu_free(request); 871 } 872 } 873 874 static void 875 icl_send_thread(void *arg) 876 { 877 struct icl_conn *ic; 878 879 ic = arg; 880 881 ICL_CONN_LOCK(ic); 882 ic->ic_send_running = true; 883 884 for (;;) { 885 if (ic->ic_disconnecting) { 886 //ICL_DEBUG("terminating"); 887 break; 888 } 889 icl_conn_send_pdus(ic); 890 cv_wait(&ic->ic_send_cv, &ic->ic_lock); 891 } 892 893 ic->ic_send_running = false; 894 ICL_CONN_UNLOCK(ic); 895 kthread_exit(); 896 } 897 898 static int 899 icl_soupcall_send(struct socket *so, void *arg, int waitflag) 900 { 901 struct icl_conn *ic; 902 903 ic = arg; 904 cv_signal(&ic->ic_send_cv); 905 return (SU_OK); 906 } 907 908 int 909 icl_pdu_append_data(struct icl_pdu *request, const void *addr, size_t len, int flags) 910 { 911 struct mbuf *mb, *newmb; 912 size_t copylen, off = 0; 913 914 KASSERT(len > 0, ("len == 0")); 915 916 newmb = m_getm2(NULL, len, flags, MT_DATA, M_PKTHDR); 917 if (newmb == NULL) { 918 ICL_WARN("failed to allocate mbuf for %zd bytes", len); 919 return (ENOMEM); 920 } 921 922 for (mb = newmb; mb != NULL; mb = mb->m_next) { 923 copylen = min(M_TRAILINGSPACE(mb), len - off); 924 memcpy(mtod(mb, char *), (const char *)addr + off, copylen); 925 mb->m_len = copylen; 926 off += copylen; 927 } 928 KASSERT(off == len, ("%s: off != len", __func__)); 929 930 if (request->ip_data_mbuf == NULL) { 931 request->ip_data_mbuf = newmb; 932 request->ip_data_len = len; 933 } else { 934 m_cat(request->ip_data_mbuf, newmb); 935 request->ip_data_len += len; 936 } 937 938 return (0); 939 } 940 941 void 942 icl_pdu_get_data(struct icl_pdu *ip, size_t off, void *addr, size_t len) 943 { 944 945 m_copydata(ip->ip_data_mbuf, off, len, addr); 946 } 947 948 void 949 icl_pdu_queue(struct icl_pdu *ip) 950 { 951 struct icl_conn *ic; 952 953 ic = ip->ip_conn; 954 955 ICL_CONN_LOCK(ic); 956 if (ic->ic_disconnecting || ic->ic_socket == NULL) { 957 ICL_DEBUG("icl_pdu_queue on closed connection"); 958 ICL_CONN_UNLOCK(ic); 959 icl_pdu_free(ip); 960 return; 961 } 962 TAILQ_INSERT_TAIL(&ic->ic_to_send, ip, ip_next); 963 ICL_CONN_UNLOCK(ic); 964 cv_signal(&ic->ic_send_cv); 965 } 966 967 struct icl_conn * 968 icl_conn_new(void) 969 { 970 struct icl_conn *ic; 971 972 refcount_acquire(&icl_ncons); 973 974 ic = uma_zalloc(icl_conn_zone, M_WAITOK | M_ZERO); 975 976 TAILQ_INIT(&ic->ic_to_send); 977 mtx_init(&ic->ic_lock, "icl_lock", NULL, MTX_DEF); 978 cv_init(&ic->ic_send_cv, "icl_tx"); 979 cv_init(&ic->ic_receive_cv, "icl_rx"); 980 refcount_init(&ic->ic_outstanding_pdus, 0); 981 ic->ic_max_data_segment_length = ICL_MAX_DATA_SEGMENT_LENGTH; 982 983 return (ic); 984 } 985 986 void 987 icl_conn_free(struct icl_conn *ic) 988 { 989 990 mtx_destroy(&ic->ic_lock); 991 cv_destroy(&ic->ic_send_cv); 992 cv_destroy(&ic->ic_receive_cv); 993 uma_zfree(icl_conn_zone, ic); 994 refcount_release(&icl_ncons); 995 } 996 997 static int 998 icl_conn_start(struct icl_conn *ic) 999 { 1000 size_t bufsize; 1001 struct sockopt opt; 1002 int error, one = 1; 1003 1004 ICL_CONN_LOCK(ic); 1005 1006 /* 1007 * XXX: Ugly hack. 1008 */ 1009 if (ic->ic_socket == NULL) { 1010 ICL_CONN_UNLOCK(ic); 1011 return (EINVAL); 1012 } 1013 1014 ic->ic_receive_state = ICL_CONN_STATE_BHS; 1015 ic->ic_receive_len = sizeof(struct iscsi_bhs); 1016 ic->ic_disconnecting = false; 1017 1018 ICL_CONN_UNLOCK(ic); 1019 1020 /* 1021 * Use max available sockbuf size for sending. Do it manually 1022 * instead of sbreserve(9) to work around resource limits. 1023 * 1024 * XXX: This kind of sucks. On one hand, we don't currently support 1025 * sending a part of data segment; we always do it in one piece, 1026 * so we have to make sure it can fit in the socket buffer. 1027 * Once I've implemented partial send, we'll get rid of this 1028 * and use autoscaling. 1029 */ 1030 bufsize = (sizeof(struct iscsi_bhs) + 1031 ic->ic_max_data_segment_length) * 8; 1032 error = soreserve(ic->ic_socket, bufsize, bufsize); 1033 if (error != 0) { 1034 ICL_WARN("soreserve failed with error %d", error); 1035 icl_conn_close(ic); 1036 return (error); 1037 } 1038 1039 /* 1040 * Disable Nagle. 1041 */ 1042 bzero(&opt, sizeof(opt)); 1043 opt.sopt_dir = SOPT_SET; 1044 opt.sopt_level = IPPROTO_TCP; 1045 opt.sopt_name = TCP_NODELAY; 1046 opt.sopt_val = &one; 1047 opt.sopt_valsize = sizeof(one); 1048 error = sosetopt(ic->ic_socket, &opt); 1049 if (error != 0) { 1050 ICL_WARN("disabling TCP_NODELAY failed with error %d", error); 1051 icl_conn_close(ic); 1052 return (error); 1053 } 1054 1055 /* 1056 * Start threads. 1057 */ 1058 error = kthread_add(icl_send_thread, ic, NULL, NULL, 0, 0, "icltx"); 1059 if (error != 0) { 1060 ICL_WARN("kthread_add(9) failed with error %d", error); 1061 icl_conn_close(ic); 1062 return (error); 1063 } 1064 1065 error = kthread_add(icl_receive_thread, ic, NULL, NULL, 0, 0, "iclrx"); 1066 if (error != 0) { 1067 ICL_WARN("kthread_add(9) failed with error %d", error); 1068 icl_conn_close(ic); 1069 return (error); 1070 } 1071 1072 /* 1073 * Register socket upcall, to get notified about incoming PDUs 1074 * and free space to send outgoing ones. 1075 */ 1076 SOCKBUF_LOCK(&ic->ic_socket->so_snd); 1077 soupcall_set(ic->ic_socket, SO_SND, icl_soupcall_send, ic); 1078 SOCKBUF_UNLOCK(&ic->ic_socket->so_snd); 1079 SOCKBUF_LOCK(&ic->ic_socket->so_rcv); 1080 soupcall_set(ic->ic_socket, SO_RCV, icl_soupcall_receive, ic); 1081 SOCKBUF_UNLOCK(&ic->ic_socket->so_rcv); 1082 1083 return (0); 1084 } 1085 1086 int 1087 icl_conn_handoff(struct icl_conn *ic, int fd) 1088 { 1089 struct file *fp; 1090 struct socket *so; 1091 cap_rights_t rights; 1092 int error; 1093 1094 /* 1095 * Steal the socket from userland. 1096 */ 1097 error = fget(curthread, fd, 1098 cap_rights_init(&rights, CAP_SOCK_CLIENT), &fp); 1099 if (error != 0) 1100 return (error); 1101 if (fp->f_type != DTYPE_SOCKET) { 1102 fdrop(fp, curthread); 1103 return (EINVAL); 1104 } 1105 so = fp->f_data; 1106 if (so->so_type != SOCK_STREAM) { 1107 fdrop(fp, curthread); 1108 return (EINVAL); 1109 } 1110 1111 ICL_CONN_LOCK(ic); 1112 1113 if (ic->ic_socket != NULL) { 1114 ICL_CONN_UNLOCK(ic); 1115 fdrop(fp, curthread); 1116 return (EBUSY); 1117 } 1118 1119 ic->ic_socket = fp->f_data; 1120 fp->f_ops = &badfileops; 1121 fp->f_data = NULL; 1122 fdrop(fp, curthread); 1123 ICL_CONN_UNLOCK(ic); 1124 1125 error = icl_conn_start(ic); 1126 1127 return (error); 1128 } 1129 1130 void 1131 icl_conn_shutdown(struct icl_conn *ic) 1132 { 1133 1134 ICL_CONN_LOCK(ic); 1135 if (ic->ic_socket == NULL) { 1136 ICL_CONN_UNLOCK(ic); 1137 return; 1138 } 1139 ICL_CONN_UNLOCK(ic); 1140 1141 soshutdown(ic->ic_socket, SHUT_RDWR); 1142 } 1143 1144 void 1145 icl_conn_close(struct icl_conn *ic) 1146 { 1147 struct icl_pdu *pdu; 1148 1149 ICL_CONN_LOCK(ic); 1150 if (ic->ic_socket == NULL) { 1151 ICL_CONN_UNLOCK(ic); 1152 return; 1153 } 1154 1155 ic->ic_disconnecting = true; 1156 1157 /* 1158 * Wake up the threads, so they can properly terminate. 1159 */ 1160 cv_signal(&ic->ic_receive_cv); 1161 cv_signal(&ic->ic_send_cv); 1162 while (ic->ic_receive_running || ic->ic_send_running) { 1163 //ICL_DEBUG("waiting for send/receive threads to terminate"); 1164 ICL_CONN_UNLOCK(ic); 1165 cv_signal(&ic->ic_receive_cv); 1166 cv_signal(&ic->ic_send_cv); 1167 pause("icl_close", 1 * hz); 1168 ICL_CONN_LOCK(ic); 1169 } 1170 //ICL_DEBUG("send/receive threads terminated"); 1171 1172 soclose(ic->ic_socket); 1173 ic->ic_socket = NULL; 1174 1175 if (ic->ic_receive_pdu != NULL) { 1176 //ICL_DEBUG("freeing partially received PDU"); 1177 icl_pdu_free(ic->ic_receive_pdu); 1178 ic->ic_receive_pdu = NULL; 1179 } 1180 1181 /* 1182 * Remove any outstanding PDUs from the send queue. 1183 */ 1184 while (!TAILQ_EMPTY(&ic->ic_to_send)) { 1185 pdu = TAILQ_FIRST(&ic->ic_to_send); 1186 TAILQ_REMOVE(&ic->ic_to_send, pdu, ip_next); 1187 icl_pdu_free(pdu); 1188 } 1189 1190 KASSERT(TAILQ_EMPTY(&ic->ic_to_send), 1191 ("destroying session with non-empty send queue")); 1192 /* 1193 * XXX 1194 */ 1195 #if 0 1196 KASSERT(ic->ic_outstanding_pdus == 0, 1197 ("destroying session with %d outstanding PDUs", 1198 ic->ic_outstanding_pdus)); 1199 #endif 1200 ICL_CONN_UNLOCK(ic); 1201 } 1202 1203 bool 1204 icl_conn_connected(struct icl_conn *ic) 1205 { 1206 1207 ICL_CONN_LOCK(ic); 1208 if (ic->ic_socket == NULL) { 1209 ICL_CONN_UNLOCK(ic); 1210 return (false); 1211 } 1212 if (ic->ic_socket->so_error != 0) { 1213 ICL_CONN_UNLOCK(ic); 1214 return (false); 1215 } 1216 ICL_CONN_UNLOCK(ic); 1217 return (true); 1218 } 1219 1220 #ifdef ICL_KERNEL_PROXY 1221 int 1222 icl_conn_handoff_sock(struct icl_conn *ic, struct socket *so) 1223 { 1224 int error; 1225 1226 if (so->so_type != SOCK_STREAM) 1227 return (EINVAL); 1228 1229 ICL_CONN_LOCK(ic); 1230 if (ic->ic_socket != NULL) { 1231 ICL_CONN_UNLOCK(ic); 1232 return (EBUSY); 1233 } 1234 ic->ic_socket = so; 1235 ICL_CONN_UNLOCK(ic); 1236 1237 error = icl_conn_start(ic); 1238 1239 return (error); 1240 } 1241 #endif /* ICL_KERNEL_PROXY */ 1242 1243 static int 1244 icl_unload(void) 1245 { 1246 1247 if (icl_ncons != 0) 1248 return (EBUSY); 1249 1250 uma_zdestroy(icl_conn_zone); 1251 uma_zdestroy(icl_pdu_zone); 1252 1253 return (0); 1254 } 1255 1256 static void 1257 icl_load(void) 1258 { 1259 1260 icl_conn_zone = uma_zcreate("icl_conn", 1261 sizeof(struct icl_conn), NULL, NULL, NULL, NULL, 1262 UMA_ALIGN_PTR, 0); 1263 icl_pdu_zone = uma_zcreate("icl_pdu", 1264 sizeof(struct icl_pdu), NULL, NULL, NULL, NULL, 1265 UMA_ALIGN_PTR, 0); 1266 1267 refcount_init(&icl_ncons, 0); 1268 } 1269 1270 static int 1271 icl_modevent(module_t mod, int what, void *arg) 1272 { 1273 1274 switch (what) { 1275 case MOD_LOAD: 1276 icl_load(); 1277 return (0); 1278 case MOD_UNLOAD: 1279 return (icl_unload()); 1280 default: 1281 return (EINVAL); 1282 } 1283 } 1284 1285 moduledata_t icl_data = { 1286 "icl", 1287 icl_modevent, 1288 0 1289 }; 1290 1291 DECLARE_MODULE(icl, icl_data, SI_SUB_DRIVERS, SI_ORDER_FIRST); 1292 MODULE_VERSION(icl, 1); 1293