sys/dev/iscsi/icl_soft.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2012 The FreeBSD Foundation
   5  * All rights reserved.
   6  *
   7  * This software was developed by Edward Tomasz Napierala under sponsorship
   8  * from the FreeBSD Foundation.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  */
  32
  33 /*
  34  * Software implementation of iSCSI Common Layer kobj(9) interface.
  35  */
  36
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD$");
  39
  40 #include <sys/param.h>
  41 #include <sys/capsicum.h>
  42 #include <sys/condvar.h>
  43 #include <sys/conf.h>
  44 #include <sys/gsb_crc32.h>
  45 #include <sys/file.h>
  46 #include <sys/kernel.h>
  47 #include <sys/kthread.h>
  48 #include <sys/lock.h>
  49 #include <sys/mbuf.h>
  50 #include <sys/mutex.h>
  51 #include <sys/module.h>
  52 #include <sys/protosw.h>
  53 #include <sys/socket.h>
  54 #include <sys/socketvar.h>
  55 #include <sys/sysctl.h>
  56 #include <sys/systm.h>
  57 #include <sys/sx.h>
  58 #include <sys/uio.h>
  59 #include <vm/uma.h>
  60 #include <netinet/in.h>
  61 #include <netinet/tcp.h>
  62
  63 #include <dev/iscsi/icl.h>
  64 #include <dev/iscsi/iscsi_proto.h>
  65 #include <icl_conn_if.h>
  66
  67 static int coalesce = 1;
  68 SYSCTL_INT(_kern_icl, OID_AUTO, coalesce, CTLFLAG_RWTUN,
  69     &coalesce, 0, "Try to coalesce PDUs before sending");
  70 static int partial_receive_len = 128 * 1024;
  71 SYSCTL_INT(_kern_icl, OID_AUTO, partial_receive_len, CTLFLAG_RWTUN,
  72     &partial_receive_len, 0, "Minimum read size for partially received "
  73     "data segment");
  74 static int sendspace = 1048576;
  75 SYSCTL_INT(_kern_icl, OID_AUTO, sendspace, CTLFLAG_RWTUN,
  76     &sendspace, 0, "Default send socket buffer size");
  77 static int recvspace = 1048576;
  78 SYSCTL_INT(_kern_icl, OID_AUTO, recvspace, CTLFLAG_RWTUN,
  79     &recvspace, 0, "Default receive socket buffer size");
  80
  81 static MALLOC_DEFINE(M_ICL_SOFT, "icl_soft", "iSCSI software backend");
  82 static uma_zone_t icl_pdu_zone;
  83
  84 static volatile u_int   icl_ncons;
  85
  86 #define ICL_CONN_LOCK(X)                mtx_lock(X->ic_lock)
  87 #define ICL_CONN_UNLOCK(X)              mtx_unlock(X->ic_lock)
  88 #define ICL_CONN_LOCK_ASSERT(X)         mtx_assert(X->ic_lock, MA_OWNED)
  89 #define ICL_CONN_LOCK_ASSERT_NOT(X)     mtx_assert(X->ic_lock, MA_NOTOWNED)
  90
  91 STAILQ_HEAD(icl_pdu_stailq, icl_pdu);
  92
  93 static icl_conn_new_pdu_t       icl_soft_conn_new_pdu;
  94 static icl_conn_pdu_free_t      icl_soft_conn_pdu_free;
  95 static icl_conn_pdu_data_segment_length_t
  96                                     icl_soft_conn_pdu_data_segment_length;
  97 static icl_conn_pdu_append_data_t       icl_soft_conn_pdu_append_data;
  98 static icl_conn_pdu_get_data_t  icl_soft_conn_pdu_get_data;
  99 static icl_conn_pdu_queue_t     icl_soft_conn_pdu_queue;
 100 static icl_conn_handoff_t       icl_soft_conn_handoff;
 101 static icl_conn_free_t          icl_soft_conn_free;
 102 static icl_conn_close_t         icl_soft_conn_close;
 103 static icl_conn_task_setup_t    icl_soft_conn_task_setup;
 104 static icl_conn_task_done_t     icl_soft_conn_task_done;
 105 static icl_conn_transfer_setup_t        icl_soft_conn_transfer_setup;
 106 static icl_conn_transfer_done_t icl_soft_conn_transfer_done;
 107 #ifdef ICL_KERNEL_PROXY
 108 static icl_conn_connect_t       icl_soft_conn_connect;
 109 #endif
 110
 111 static kobj_method_t icl_soft_methods[] = {
 112         KOBJMETHOD(icl_conn_new_pdu, icl_soft_conn_new_pdu),
 113         KOBJMETHOD(icl_conn_pdu_free, icl_soft_conn_pdu_free),
 114         KOBJMETHOD(icl_conn_pdu_data_segment_length,
 115             icl_soft_conn_pdu_data_segment_length),
 116         KOBJMETHOD(icl_conn_pdu_append_data, icl_soft_conn_pdu_append_data),
 117         KOBJMETHOD(icl_conn_pdu_get_data, icl_soft_conn_pdu_get_data),
 118         KOBJMETHOD(icl_conn_pdu_queue, icl_soft_conn_pdu_queue),
 119         KOBJMETHOD(icl_conn_handoff, icl_soft_conn_handoff),
 120         KOBJMETHOD(icl_conn_free, icl_soft_conn_free),
 121         KOBJMETHOD(icl_conn_close, icl_soft_conn_close),
 122         KOBJMETHOD(icl_conn_task_setup, icl_soft_conn_task_setup),
 123         KOBJMETHOD(icl_conn_task_done, icl_soft_conn_task_done),
 124         KOBJMETHOD(icl_conn_transfer_setup, icl_soft_conn_transfer_setup),
 125         KOBJMETHOD(icl_conn_transfer_done, icl_soft_conn_transfer_done),
 126 #ifdef ICL_KERNEL_PROXY
 127         KOBJMETHOD(icl_conn_connect, icl_soft_conn_connect),
 128 #endif
 129         { 0, 0 }
 130 };
 131
 132 DEFINE_CLASS(icl_soft, icl_soft_methods, sizeof(struct icl_conn));
 133
 134 static void
 135 icl_conn_fail(struct icl_conn *ic)
 136 {
 137         if (ic->ic_socket == NULL)
 138                 return;
 139
 140         /*
 141          * XXX
 142          */
 143         ic->ic_socket->so_error = EDOOFUS;
 144         (ic->ic_error)(ic);
 145 }
 146
 147 static struct mbuf *
 148 icl_conn_receive(struct icl_conn *ic, size_t len)
 149 {
 150         struct uio uio;
 151         struct socket *so;
 152         struct mbuf *m;
 153         int error, flags;
 154
 155         so = ic->ic_socket;
 156
 157         memset(&uio, 0, sizeof(uio));
 158         uio.uio_resid = len;
 159
 160         flags = MSG_DONTWAIT;
 161         error = soreceive(so, NULL, &uio, &m, NULL, &flags);
 162         if (error != 0) {
 163                 ICL_DEBUG("soreceive error %d", error);
 164                 return (NULL);
 165         }
 166         if (uio.uio_resid != 0) {
 167                 m_freem(m);
 168                 ICL_DEBUG("short read");
 169                 return (NULL);
 170         }
 171
 172         return (m);
 173 }
 174
 175 static int
 176 icl_conn_receive_buf(struct icl_conn *ic, void *buf, size_t len)
 177 {
 178         struct iovec iov[1];
 179         struct uio uio;
 180         struct socket *so;
 181         int error, flags;
 182
 183         so = ic->ic_socket;
 184
 185         memset(&uio, 0, sizeof(uio));
 186         iov[0].iov_base = buf;
 187         iov[0].iov_len = len;
 188         uio.uio_iov = iov;
 189         uio.uio_iovcnt = 1;
 190         uio.uio_offset = 0;
 191         uio.uio_resid = len;
 192         uio.uio_segflg = UIO_SYSSPACE;
 193         uio.uio_rw = UIO_READ;
 194
 195         flags = MSG_DONTWAIT;
 196         error = soreceive(so, NULL, &uio, NULL, NULL, &flags);
 197         if (error != 0) {
 198                 ICL_DEBUG("soreceive error %d", error);
 199                 return (-1);
 200         }
 201         if (uio.uio_resid != 0) {
 202                 ICL_DEBUG("short read");
 203                 return (-1);
 204         }
 205
 206         return (0);
 207 }
 208
 209 static void
 210 icl_soft_conn_pdu_free(struct icl_conn *ic, struct icl_pdu *ip)
 211 {
 212
 213         m_freem(ip->ip_bhs_mbuf);
 214         m_freem(ip->ip_ahs_mbuf);
 215         m_freem(ip->ip_data_mbuf);
 216         uma_zfree(icl_pdu_zone, ip);
 217 #ifdef DIAGNOSTIC
 218         refcount_release(&ic->ic_outstanding_pdus);
 219 #endif
 220 }
 221
 222 /*
 223  * Allocate icl_pdu with empty BHS to fill up by the caller.
 224  */
 225 struct icl_pdu *
 226 icl_soft_conn_new_pdu(struct icl_conn *ic, int flags)
 227 {
 228         struct icl_pdu *ip;
 229
 230 #ifdef DIAGNOSTIC
 231         refcount_acquire(&ic->ic_outstanding_pdus);
 232 #endif
 233         ip = uma_zalloc(icl_pdu_zone, flags | M_ZERO);
 234         if (ip == NULL) {
 235                 ICL_WARN("failed to allocate %zd bytes", sizeof(*ip));
 236 #ifdef DIAGNOSTIC
 237                 refcount_release(&ic->ic_outstanding_pdus);
 238 #endif
 239                 return (NULL);
 240         }
 241         ip->ip_conn = ic;
 242
 243         CTASSERT(sizeof(struct iscsi_bhs) <= MHLEN);
 244         ip->ip_bhs_mbuf = m_gethdr(flags, MT_DATA);
 245         if (ip->ip_bhs_mbuf == NULL) {
 246                 ICL_WARN("failed to allocate BHS mbuf");
 247                 icl_soft_conn_pdu_free(ic, ip);
 248                 return (NULL);
 249         }
 250         ip->ip_bhs = mtod(ip->ip_bhs_mbuf, struct iscsi_bhs *);
 251         memset(ip->ip_bhs, 0, sizeof(struct iscsi_bhs));
 252         ip->ip_bhs_mbuf->m_len = sizeof(struct iscsi_bhs);
 253
 254         return (ip);
 255 }
 256
 257 static int
 258 icl_pdu_ahs_length(const struct icl_pdu *request)
 259 {
 260
 261         return (request->ip_bhs->bhs_total_ahs_len * 4);
 262 }
 263
 264 static size_t
 265 icl_pdu_data_segment_length(const struct icl_pdu *request)
 266 {
 267         uint32_t len = 0;
 268
 269         len += request->ip_bhs->bhs_data_segment_len[0];
 270         len <<= 8;
 271         len += request->ip_bhs->bhs_data_segment_len[1];
 272         len <<= 8;
 273         len += request->ip_bhs->bhs_data_segment_len[2];
 274
 275         return (len);
 276 }
 277
 278 size_t
 279 icl_soft_conn_pdu_data_segment_length(struct icl_conn *ic,
 280     const struct icl_pdu *request)
 281 {
 282
 283         return (icl_pdu_data_segment_length(request));
 284 }
 285
 286 static void
 287 icl_pdu_set_data_segment_length(struct icl_pdu *response, uint32_t len)
 288 {
 289
 290         response->ip_bhs->bhs_data_segment_len[2] = len;
 291         response->ip_bhs->bhs_data_segment_len[1] = len >> 8;
 292         response->ip_bhs->bhs_data_segment_len[0] = len >> 16;
 293 }
 294
 295 static size_t
 296 icl_pdu_padding(const struct icl_pdu *ip)
 297 {
 298
 299         if ((ip->ip_data_len % 4) != 0)
 300                 return (4 - (ip->ip_data_len % 4));
 301
 302         return (0);
 303 }
 304
 305 static size_t
 306 icl_pdu_size(const struct icl_pdu *response)
 307 {
 308         size_t len;
 309
 310         KASSERT(response->ip_ahs_len == 0, ("responding with AHS"));
 311
 312         len = sizeof(struct iscsi_bhs) + response->ip_data_len +
 313             icl_pdu_padding(response);
 314         if (response->ip_conn->ic_header_crc32c)
 315                 len += ISCSI_HEADER_DIGEST_SIZE;
 316         if (response->ip_data_len != 0 && response->ip_conn->ic_data_crc32c)
 317                 len += ISCSI_DATA_DIGEST_SIZE;
 318
 319         return (len);
 320 }
 321
 322 static int
 323 icl_pdu_receive_bhs(struct icl_pdu *request, size_t *availablep)
 324 {
 325
 326         if (icl_conn_receive_buf(request->ip_conn,
 327             request->ip_bhs, sizeof(struct iscsi_bhs))) {
 328                 ICL_DEBUG("failed to receive BHS");
 329                 return (-1);
 330         }
 331
 332         *availablep -= sizeof(struct iscsi_bhs);
 333         return (0);
 334 }
 335
 336 static int
 337 icl_pdu_receive_ahs(struct icl_pdu *request, size_t *availablep)
 338 {
 339
 340         request->ip_ahs_len = icl_pdu_ahs_length(request);
 341         if (request->ip_ahs_len == 0)
 342                 return (0);
 343
 344         request->ip_ahs_mbuf = icl_conn_receive(request->ip_conn,
 345             request->ip_ahs_len);
 346         if (request->ip_ahs_mbuf == NULL) {
 347                 ICL_DEBUG("failed to receive AHS");
 348                 return (-1);
 349         }
 350
 351         *availablep -= request->ip_ahs_len;
 352         return (0);
 353 }
 354
 355 static uint32_t
 356 icl_mbuf_to_crc32c(const struct mbuf *m0)
 357 {
 358         uint32_t digest = 0xffffffff;
 359         const struct mbuf *m;
 360
 361         for (m = m0; m != NULL; m = m->m_next)
 362                 digest = calculate_crc32c(digest,
 363                     mtod(m, const void *), m->m_len);
 364
 365         digest = digest ^ 0xffffffff;
 366
 367         return (digest);
 368 }
 369
 370 static int
 371 icl_pdu_check_header_digest(struct icl_pdu *request, size_t *availablep)
 372 {
 373         uint32_t received_digest, valid_digest;
 374
 375         if (request->ip_conn->ic_header_crc32c == false)
 376                 return (0);
 377
 378         CTASSERT(sizeof(received_digest) == ISCSI_HEADER_DIGEST_SIZE);
 379         if (icl_conn_receive_buf(request->ip_conn,
 380             &received_digest, ISCSI_HEADER_DIGEST_SIZE)) {
 381                 ICL_DEBUG("failed to receive header digest");
 382                 return (-1);
 383         }
 384         *availablep -= ISCSI_HEADER_DIGEST_SIZE;
 385
 386         /* Temporary attach AHS to BHS to calculate header digest. */
 387         request->ip_bhs_mbuf->m_next = request->ip_ahs_mbuf;
 388         valid_digest = icl_mbuf_to_crc32c(request->ip_bhs_mbuf);
 389         request->ip_bhs_mbuf->m_next = NULL;
 390         if (received_digest != valid_digest) {
 391                 ICL_WARN("header digest check failed; got 0x%x, "
 392                     "should be 0x%x", received_digest, valid_digest);
 393                 return (-1);
 394         }
 395
 396         return (0);
 397 }
 398
 399 /*
 400  * Return the number of bytes that should be waiting in the receive socket
 401  * before icl_pdu_receive_data_segment() gets called.
 402  */
 403 static size_t
 404 icl_pdu_data_segment_receive_len(const struct icl_pdu *request)
 405 {
 406         size_t len;
 407
 408         len = icl_pdu_data_segment_length(request);
 409         if (len == 0)
 410                 return (0);
 411
 412         /*
 413          * Account for the parts of data segment already read from
 414          * the socket buffer.
 415          */
 416         KASSERT(len > request->ip_data_len, ("len <= request->ip_data_len"));
 417         len -= request->ip_data_len;
 418
 419         /*
 420          * Don't always wait for the full data segment to be delivered
 421          * to the socket; this might badly affect performance due to
 422          * TCP window scaling.
 423          */
 424         if (len > partial_receive_len) {
 425 #if 0
 426                 ICL_DEBUG("need %zd bytes of data, limiting to %zd",
 427                     len, partial_receive_len));
 428 #endif
 429                 len = partial_receive_len;
 430
 431                 return (len);
 432         }
 433
 434         /*
 435          * Account for padding.  Note that due to the way code is written,
 436          * the icl_pdu_receive_data_segment() must always receive padding
 437          * along with the last part of data segment, because it would be
 438          * impossible to tell whether we've already received the full data
 439          * segment including padding, or without it.
 440          */
 441         if ((len % 4) != 0)
 442                 len += 4 - (len % 4);
 443
 444 #if 0
 445         ICL_DEBUG("need %zd bytes of data", len));
 446 #endif
 447
 448         return (len);
 449 }
 450
 451 static int
 452 icl_pdu_receive_data_segment(struct icl_pdu *request,
 453     size_t *availablep, bool *more_neededp)
 454 {
 455         struct icl_conn *ic;
 456         size_t len, padding = 0;
 457         struct mbuf *m;
 458
 459         ic = request->ip_conn;
 460
 461         *more_neededp = false;
 462         ic->ic_receive_len = 0;
 463
 464         len = icl_pdu_data_segment_length(request);
 465         if (len == 0)
 466                 return (0);
 467
 468         if ((len % 4) != 0)
 469                 padding = 4 - (len % 4);
 470
 471         /*
 472          * Account for already received parts of data segment.
 473          */
 474         KASSERT(len > request->ip_data_len, ("len <= request->ip_data_len"));
 475         len -= request->ip_data_len;
 476
 477         if (len + padding > *availablep) {
 478                 /*
 479                  * Not enough data in the socket buffer.  Receive as much
 480                  * as we can.  Don't receive padding, since, obviously, it's
 481                  * not the end of data segment yet.
 482                  */
 483 #if 0
 484                 ICL_DEBUG("limited from %zd to %zd",
 485                     len + padding, *availablep - padding));
 486 #endif
 487                 len = *availablep - padding;
 488                 *more_neededp = true;
 489                 padding = 0;
 490         }
 491
 492         /*
 493          * Must not try to receive padding without at least one byte
 494          * of actual data segment.
 495          */
 496         if (len > 0) {
 497                 m = icl_conn_receive(request->ip_conn, len + padding);
 498                 if (m == NULL) {
 499                         ICL_DEBUG("failed to receive data segment");
 500                         return (-1);
 501                 }
 502
 503                 if (request->ip_data_mbuf == NULL)
 504                         request->ip_data_mbuf = m;
 505                 else
 506                         m_cat(request->ip_data_mbuf, m);
 507
 508                 request->ip_data_len += len;
 509                 *availablep -= len + padding;
 510         } else
 511                 ICL_DEBUG("len 0");
 512
 513         if (*more_neededp)
 514                 ic->ic_receive_len =
 515                     icl_pdu_data_segment_receive_len(request);
 516
 517         return (0);
 518 }
 519
 520 static int
 521 icl_pdu_check_data_digest(struct icl_pdu *request, size_t *availablep)
 522 {
 523         uint32_t received_digest, valid_digest;
 524
 525         if (request->ip_conn->ic_data_crc32c == false)
 526                 return (0);
 527
 528         if (request->ip_data_len == 0)
 529                 return (0);
 530
 531         CTASSERT(sizeof(received_digest) == ISCSI_DATA_DIGEST_SIZE);
 532         if (icl_conn_receive_buf(request->ip_conn,
 533             &received_digest, ISCSI_DATA_DIGEST_SIZE)) {
 534                 ICL_DEBUG("failed to receive data digest");
 535                 return (-1);
 536         }
 537         *availablep -= ISCSI_DATA_DIGEST_SIZE;
 538
 539         /*
 540          * Note that ip_data_mbuf also contains padding; since digest
 541          * calculation is supposed to include that, we iterate over
 542          * the entire ip_data_mbuf chain, not just ip_data_len bytes of it.
 543          */
 544         valid_digest = icl_mbuf_to_crc32c(request->ip_data_mbuf);
 545         if (received_digest != valid_digest) {
 546                 ICL_WARN("data digest check failed; got 0x%x, "
 547                     "should be 0x%x", received_digest, valid_digest);
 548                 return (-1);
 549         }
 550
 551         return (0);
 552 }
 553
 554 /*
 555  * Somewhat contrary to the name, this attempts to receive only one
 556  * "part" of PDU at a time; call it repeatedly until it returns non-NULL.
 557  */
 558 static struct icl_pdu *
 559 icl_conn_receive_pdu(struct icl_conn *ic, size_t *availablep)
 560 {
 561         struct icl_pdu *request;
 562         struct socket *so;
 563         size_t len;
 564         int error;
 565         bool more_needed;
 566
 567         so = ic->ic_socket;
 568
 569         if (ic->ic_receive_state == ICL_CONN_STATE_BHS) {
 570                 KASSERT(ic->ic_receive_pdu == NULL,
 571                     ("ic->ic_receive_pdu != NULL"));
 572                 request = icl_soft_conn_new_pdu(ic, M_NOWAIT);
 573                 if (request == NULL) {
 574                         ICL_DEBUG("failed to allocate PDU; "
 575                             "dropping connection");
 576                         icl_conn_fail(ic);
 577                         return (NULL);
 578                 }
 579                 ic->ic_receive_pdu = request;
 580         } else {
 581                 KASSERT(ic->ic_receive_pdu != NULL,
 582                     ("ic->ic_receive_pdu == NULL"));
 583                 request = ic->ic_receive_pdu;
 584         }
 585
 586         if (*availablep < ic->ic_receive_len) {
 587 #if 0
 588                 ICL_DEBUG("not enough data; need %zd, "
 589                     "have %zd", ic->ic_receive_len, *availablep);
 590 #endif
 591                 return (NULL);
 592         }
 593
 594         switch (ic->ic_receive_state) {
 595         case ICL_CONN_STATE_BHS:
 596                 //ICL_DEBUG("receiving BHS");
 597                 error = icl_pdu_receive_bhs(request, availablep);
 598                 if (error != 0) {
 599                         ICL_DEBUG("failed to receive BHS; "
 600                             "dropping connection");
 601                         break;
 602                 }
 603
 604                 /*
 605                  * We don't enforce any limit for AHS length;
 606                  * its length is stored in 8 bit field.
 607                  */
 608
 609                 len = icl_pdu_data_segment_length(request);
 610                 if (len > ic->ic_max_data_segment_length) {
 611                         ICL_WARN("received data segment "
 612                             "length %zd is larger than negotiated "
 613                             "MaxDataSegmentLength %zd; "
 614                             "dropping connection",
 615                             len, ic->ic_max_data_segment_length);
 616                         error = EINVAL;
 617                         break;
 618                 }
 619
 620                 ic->ic_receive_state = ICL_CONN_STATE_AHS;
 621                 ic->ic_receive_len = icl_pdu_ahs_length(request);
 622                 break;
 623
 624         case ICL_CONN_STATE_AHS:
 625                 //ICL_DEBUG("receiving AHS");
 626                 error = icl_pdu_receive_ahs(request, availablep);
 627                 if (error != 0) {
 628                         ICL_DEBUG("failed to receive AHS; "
 629                             "dropping connection");
 630                         break;
 631                 }
 632                 ic->ic_receive_state = ICL_CONN_STATE_HEADER_DIGEST;
 633                 if (ic->ic_header_crc32c == false)
 634                         ic->ic_receive_len = 0;
 635                 else
 636                         ic->ic_receive_len = ISCSI_HEADER_DIGEST_SIZE;
 637                 break;
 638
 639         case ICL_CONN_STATE_HEADER_DIGEST:
 640                 //ICL_DEBUG("receiving header digest");
 641                 error = icl_pdu_check_header_digest(request, availablep);
 642                 if (error != 0) {
 643                         ICL_DEBUG("header digest failed; "
 644                             "dropping connection");
 645                         break;
 646                 }
 647
 648                 ic->ic_receive_state = ICL_CONN_STATE_DATA;
 649                 ic->ic_receive_len =
 650                     icl_pdu_data_segment_receive_len(request);
 651                 break;
 652
 653         case ICL_CONN_STATE_DATA:
 654                 //ICL_DEBUG("receiving data segment");
 655                 error = icl_pdu_receive_data_segment(request, availablep,
 656                     &more_needed);
 657                 if (error != 0) {
 658                         ICL_DEBUG("failed to receive data segment;"
 659                             "dropping connection");
 660                         break;
 661                 }
 662
 663                 if (more_needed)
 664                         break;
 665
 666                 ic->ic_receive_state = ICL_CONN_STATE_DATA_DIGEST;
 667                 if (request->ip_data_len == 0 || ic->ic_data_crc32c == false)
 668                         ic->ic_receive_len = 0;
 669                 else
 670                         ic->ic_receive_len = ISCSI_DATA_DIGEST_SIZE;
 671                 break;
 672
 673         case ICL_CONN_STATE_DATA_DIGEST:
 674                 //ICL_DEBUG("receiving data digest");
 675                 error = icl_pdu_check_data_digest(request, availablep);
 676                 if (error != 0) {
 677                         ICL_DEBUG("data digest failed; "
 678                             "dropping connection");
 679                         break;
 680                 }
 681
 682                 /*
 683                  * We've received complete PDU; reset the receive state machine
 684                  * and return the PDU.
 685                  */
 686                 ic->ic_receive_state = ICL_CONN_STATE_BHS;
 687                 ic->ic_receive_len = sizeof(struct iscsi_bhs);
 688                 ic->ic_receive_pdu = NULL;
 689                 return (request);
 690
 691         default:
 692                 panic("invalid ic_receive_state %d\n", ic->ic_receive_state);
 693         }
 694
 695         if (error != 0) {
 696                 /*
 697                  * Don't free the PDU; it's pointed to by ic->ic_receive_pdu
 698                  * and will get freed in icl_soft_conn_close().
 699                  */
 700                 icl_conn_fail(ic);
 701         }
 702
 703         return (NULL);
 704 }
 705
 706 static void
 707 icl_conn_receive_pdus(struct icl_conn *ic, size_t available)
 708 {
 709         struct icl_pdu *response;
 710         struct socket *so;
 711
 712         so = ic->ic_socket;
 713
 714         /*
 715          * This can never happen; we're careful to only mess with ic->ic_socket
 716          * pointer when the send/receive threads are not running.
 717          */
 718         KASSERT(so != NULL, ("NULL socket"));
 719
 720         for (;;) {
 721                 if (ic->ic_disconnecting)
 722                         return;
 723
 724                 if (so->so_error != 0) {
 725                         ICL_DEBUG("connection error %d; "
 726                             "dropping connection", so->so_error);
 727                         icl_conn_fail(ic);
 728                         return;
 729                 }
 730
 731                 /*
 732                  * Loop until we have a complete PDU or there is not enough
 733                  * data in the socket buffer.
 734                  */
 735                 if (available < ic->ic_receive_len) {
 736 #if 0
 737                         ICL_DEBUG("not enough data; have %zd, "
 738                             "need %zd", available,
 739                             ic->ic_receive_len);
 740 #endif
 741                         return;
 742                 }
 743
 744                 response = icl_conn_receive_pdu(ic, &available);
 745                 if (response == NULL)
 746                         continue;
 747
 748                 if (response->ip_ahs_len > 0) {
 749                         ICL_WARN("received PDU with unsupported "
 750                             "AHS; opcode 0x%x; dropping connection",
 751                             response->ip_bhs->bhs_opcode);
 752                         icl_soft_conn_pdu_free(ic, response);
 753                         icl_conn_fail(ic);
 754                         return;
 755                 }
 756
 757                 (ic->ic_receive)(response);
 758         }
 759 }
 760
 761 static void
 762 icl_receive_thread(void *arg)
 763 {
 764         struct icl_conn *ic;
 765         size_t available;
 766         struct socket *so;
 767
 768         ic = arg;
 769         so = ic->ic_socket;
 770
 771         for (;;) {
 772                 if (ic->ic_disconnecting) {
 773                         //ICL_DEBUG("terminating");
 774                         break;
 775                 }
 776
 777                 /*
 778                  * Set the low watermark, to be checked by
 779                  * soreadable() in icl_soupcall_receive()
 780                  * to avoid unnecessary wakeups until there
 781                  * is enough data received to read the PDU.
 782                  */
 783                 SOCKBUF_LOCK(&so->so_rcv);
 784                 available = sbavail(&so->so_rcv);
 785                 if (available < ic->ic_receive_len) {
 786                         so->so_rcv.sb_lowat = ic->ic_receive_len;
 787                         cv_wait(&ic->ic_receive_cv, &so->so_rcv.sb_mtx);
 788                 } else
 789                         so->so_rcv.sb_lowat = so->so_rcv.sb_hiwat + 1;
 790                 SOCKBUF_UNLOCK(&so->so_rcv);
 791
 792                 icl_conn_receive_pdus(ic, available);
 793         }
 794
 795         ICL_CONN_LOCK(ic);
 796         ic->ic_receive_running = false;
 797         cv_signal(&ic->ic_send_cv);
 798         ICL_CONN_UNLOCK(ic);
 799         kthread_exit();
 800 }
 801
 802 static int
 803 icl_soupcall_receive(struct socket *so, void *arg, int waitflag)
 804 {
 805         struct icl_conn *ic;
 806
 807         if (!soreadable(so))
 808                 return (SU_OK);
 809
 810         ic = arg;
 811         cv_signal(&ic->ic_receive_cv);
 812         return (SU_OK);
 813 }
 814
 815 static int
 816 icl_pdu_finalize(struct icl_pdu *request)
 817 {
 818         size_t padding, pdu_len;
 819         uint32_t digest, zero = 0;
 820         int ok;
 821         struct icl_conn *ic;
 822
 823         ic = request->ip_conn;
 824
 825         icl_pdu_set_data_segment_length(request, request->ip_data_len);
 826
 827         pdu_len = icl_pdu_size(request);
 828
 829         if (ic->ic_header_crc32c) {
 830                 digest = icl_mbuf_to_crc32c(request->ip_bhs_mbuf);
 831                 ok = m_append(request->ip_bhs_mbuf, sizeof(digest),
 832                     (void *)&digest);
 833                 if (ok != 1) {
 834                         ICL_WARN("failed to append header digest");
 835                         return (1);
 836                 }
 837         }
 838
 839         if (request->ip_data_len != 0) {
 840                 padding = icl_pdu_padding(request);
 841                 if (padding > 0) {
 842                         ok = m_append(request->ip_data_mbuf, padding,
 843                             (void *)&zero);
 844                         if (ok != 1) {
 845                                 ICL_WARN("failed to append padding");
 846                                 return (1);
 847                         }
 848                 }
 849
 850                 if (ic->ic_data_crc32c) {
 851                         digest = icl_mbuf_to_crc32c(request->ip_data_mbuf);
 852
 853                         ok = m_append(request->ip_data_mbuf, sizeof(digest),
 854                             (void *)&digest);
 855                         if (ok != 1) {
 856                                 ICL_WARN("failed to append data digest");
 857                                 return (1);
 858                         }
 859                 }
 860
 861                 m_cat(request->ip_bhs_mbuf, request->ip_data_mbuf);
 862                 request->ip_data_mbuf = NULL;
 863         }
 864
 865         request->ip_bhs_mbuf->m_pkthdr.len = pdu_len;
 866
 867         return (0);
 868 }
 869
 870 static void
 871 icl_conn_send_pdus(struct icl_conn *ic, struct icl_pdu_stailq *queue)
 872 {
 873         struct icl_pdu *request, *request2;
 874         struct socket *so;
 875         long available, size, size2;
 876         int coalesced, error;
 877
 878         ICL_CONN_LOCK_ASSERT_NOT(ic);
 879
 880         so = ic->ic_socket;
 881
 882         SOCKBUF_LOCK(&so->so_snd);
 883         /*
 884          * Check how much space do we have for transmit.  We can't just
 885          * call sosend() and retry when we get EWOULDBLOCK or EMSGSIZE,
 886          * as it always frees the mbuf chain passed to it, even in case
 887          * of error.
 888          */
 889         available = sbspace(&so->so_snd);
 890
 891         /*
 892          * Notify the socket upcall that we don't need wakeups
 893          * for the time being.
 894          */
 895         so->so_snd.sb_lowat = so->so_snd.sb_hiwat + 1;
 896         SOCKBUF_UNLOCK(&so->so_snd);
 897
 898         while (!STAILQ_EMPTY(queue)) {
 899                 request = STAILQ_FIRST(queue);
 900                 size = icl_pdu_size(request);
 901                 if (available < size) {
 902
 903                         /*
 904                          * Set the low watermark, to be checked by
 905                          * sowriteable() in icl_soupcall_send()
 906                          * to avoid unnecessary wakeups until there
 907                          * is enough space for the PDU to fit.
 908                          */
 909                         SOCKBUF_LOCK(&so->so_snd);
 910                         available = sbspace(&so->so_snd);
 911                         if (available < size) {
 912 #if 1
 913                                 ICL_DEBUG("no space to send; "
 914                                     "have %ld, need %ld",
 915                                     available, size);
 916 #endif
 917                                 so->so_snd.sb_lowat = max(size,
 918                                     so->so_snd.sb_hiwat / 8);
 919                                 SOCKBUF_UNLOCK(&so->so_snd);
 920                                 return;
 921                         }
 922                         SOCKBUF_UNLOCK(&so->so_snd);
 923                 }
 924                 STAILQ_REMOVE_HEAD(queue, ip_next);
 925                 error = icl_pdu_finalize(request);
 926                 if (error != 0) {
 927                         ICL_DEBUG("failed to finalize PDU; "
 928                             "dropping connection");
 929                         icl_soft_conn_pdu_free(ic, request);
 930                         icl_conn_fail(ic);
 931                         return;
 932                 }
 933                 if (coalesce) {
 934                         coalesced = 1;
 935                         for (;;) {
 936                                 request2 = STAILQ_FIRST(queue);
 937                                 if (request2 == NULL)
 938                                         break;
 939                                 size2 = icl_pdu_size(request2);
 940                                 if (available < size + size2)
 941                                         break;
 942                                 STAILQ_REMOVE_HEAD(queue, ip_next);
 943                                 error = icl_pdu_finalize(request2);
 944                                 if (error != 0) {
 945                                         ICL_DEBUG("failed to finalize PDU; "
 946                                             "dropping connection");
 947                                         icl_soft_conn_pdu_free(ic, request);
 948                                         icl_soft_conn_pdu_free(ic, request2);
 949                                         icl_conn_fail(ic);
 950                                         return;
 951                                 }
 952                                 m_cat(request->ip_bhs_mbuf, request2->ip_bhs_mbuf);
 953                                 request2->ip_bhs_mbuf = NULL;
 954                                 request->ip_bhs_mbuf->m_pkthdr.len += size2;
 955                                 size += size2;
 956                                 STAILQ_REMOVE_AFTER(queue, request, ip_next);
 957                                 icl_soft_conn_pdu_free(ic, request2);
 958                                 coalesced++;
 959                         }
 960 #if 0
 961                         if (coalesced > 1) {
 962                                 ICL_DEBUG("coalesced %d PDUs into %ld bytes",
 963                                     coalesced, size);
 964                         }
 965 #endif
 966                 }
 967                 available -= size;
 968                 error = sosend(so, NULL, NULL, request->ip_bhs_mbuf,
 969                     NULL, MSG_DONTWAIT, curthread);
 970                 request->ip_bhs_mbuf = NULL; /* Sosend consumes the mbuf. */
 971                 if (error != 0) {
 972                         ICL_DEBUG("failed to send PDU, error %d; "
 973                             "dropping connection", error);
 974                         icl_soft_conn_pdu_free(ic, request);
 975                         icl_conn_fail(ic);
 976                         return;
 977                 }
 978                 icl_soft_conn_pdu_free(ic, request);
 979         }
 980 }
 981
 982 static void
 983 icl_send_thread(void *arg)
 984 {
 985         struct icl_conn *ic;
 986         struct icl_pdu_stailq queue;
 987
 988         ic = arg;
 989
 990         STAILQ_INIT(&queue);
 991
 992         ICL_CONN_LOCK(ic);
 993         for (;;) {
 994                 for (;;) {
 995                         /*
 996                          * If the local queue is empty, populate it from
 997                          * the main one.  This way the icl_conn_send_pdus()
 998                          * can go through all the queued PDUs without holding
 999                          * any locks.
1000                          */
1001                         if (STAILQ_EMPTY(&queue))
1002                                 STAILQ_SWAP(&ic->ic_to_send, &queue, icl_pdu);
1003
1004                         ic->ic_check_send_space = false;
1005                         ICL_CONN_UNLOCK(ic);
1006                         icl_conn_send_pdus(ic, &queue);
1007                         ICL_CONN_LOCK(ic);
1008
1009                         /*
1010                          * The icl_soupcall_send() was called since the last
1011                          * call to sbspace(); go around;
1012                          */
1013                         if (ic->ic_check_send_space)
1014                                 continue;
1015
1016                         /*
1017                          * Local queue is empty, but we still have PDUs
1018                          * in the main one; go around.
1019                          */
1020                         if (STAILQ_EMPTY(&queue) &&
1021                             !STAILQ_EMPTY(&ic->ic_to_send))
1022                                 continue;
1023
1024                         /*
1025                          * There might be some stuff in the local queue,
1026                          * which didn't get sent due to not having enough send
1027                          * space.  Wait for socket upcall.
1028                          */
1029                         break;
1030                 }
1031
1032                 if (ic->ic_disconnecting) {
1033                         //ICL_DEBUG("terminating");
1034                         break;
1035                 }
1036
1037                 cv_wait(&ic->ic_send_cv, ic->ic_lock);
1038         }
1039
1040         /*
1041          * We're exiting; move PDUs back to the main queue, so they can
1042          * get freed properly.  At this point ordering doesn't matter.
1043          */
1044         STAILQ_CONCAT(&ic->ic_to_send, &queue);
1045
1046         ic->ic_send_running = false;
1047         cv_signal(&ic->ic_send_cv);
1048         ICL_CONN_UNLOCK(ic);
1049         kthread_exit();
1050 }
1051
1052 static int
1053 icl_soupcall_send(struct socket *so, void *arg, int waitflag)
1054 {
1055         struct icl_conn *ic;
1056
1057         if (!sowriteable(so))
1058                 return (SU_OK);
1059
1060         ic = arg;
1061
1062         ICL_CONN_LOCK(ic);
1063         ic->ic_check_send_space = true;
1064         ICL_CONN_UNLOCK(ic);
1065
1066         cv_signal(&ic->ic_send_cv);
1067
1068         return (SU_OK);
1069 }
1070
1071 static int
1072 icl_soft_conn_pdu_append_data(struct icl_conn *ic, struct icl_pdu *request,
1073     const void *addr, size_t len, int flags)
1074 {
1075         struct mbuf *mb, *newmb;
1076         size_t copylen, off = 0;
1077
1078         KASSERT(len > 0, ("len == 0"));
1079
1080         newmb = m_getm2(NULL, len, flags, MT_DATA, 0);
1081         if (newmb == NULL) {
1082                 ICL_WARN("failed to allocate mbuf for %zd bytes", len);
1083                 return (ENOMEM);
1084         }
1085
1086         for (mb = newmb; mb != NULL; mb = mb->m_next) {
1087                 copylen = min(M_TRAILINGSPACE(mb), len - off);
1088                 memcpy(mtod(mb, char *), (const char *)addr + off, copylen);
1089                 mb->m_len = copylen;
1090                 off += copylen;
1091         }
1092         KASSERT(off == len, ("%s: off != len", __func__));
1093
1094         if (request->ip_data_mbuf == NULL) {
1095                 request->ip_data_mbuf = newmb;
1096                 request->ip_data_len = len;
1097         } else {
1098                 m_cat(request->ip_data_mbuf, newmb);
1099                 request->ip_data_len += len;
1100         }
1101
1102         return (0);
1103 }
1104
1105 void
1106 icl_soft_conn_pdu_get_data(struct icl_conn *ic, struct icl_pdu *ip,
1107     size_t off, void *addr, size_t len)
1108 {
1109
1110         m_copydata(ip->ip_data_mbuf, off, len, addr);
1111 }
1112
1113 static void
1114 icl_pdu_queue(struct icl_pdu *ip)
1115 {
1116         struct icl_conn *ic;
1117
1118         ic = ip->ip_conn;
1119
1120         ICL_CONN_LOCK_ASSERT(ic);
1121
1122         if (ic->ic_disconnecting || ic->ic_socket == NULL) {
1123                 ICL_DEBUG("icl_pdu_queue on closed connection");
1124                 icl_soft_conn_pdu_free(ic, ip);
1125                 return;
1126         }
1127
1128         if (!STAILQ_EMPTY(&ic->ic_to_send)) {
1129                 STAILQ_INSERT_TAIL(&ic->ic_to_send, ip, ip_next);
1130                 /*
1131                  * If the queue is not empty, someone else had already
1132                  * signaled the send thread; no need to do that again,
1133                  * just return.
1134                  */
1135                 return;
1136         }
1137
1138         STAILQ_INSERT_TAIL(&ic->ic_to_send, ip, ip_next);
1139         cv_signal(&ic->ic_send_cv);
1140 }
1141
1142 void
1143 icl_soft_conn_pdu_queue(struct icl_conn *ic, struct icl_pdu *ip)
1144 {
1145
1146         icl_pdu_queue(ip);
1147 }
1148
1149 static struct icl_conn *
1150 icl_soft_new_conn(const char *name, struct mtx *lock)
1151 {
1152         struct icl_conn *ic;
1153
1154         refcount_acquire(&icl_ncons);
1155
1156         ic = (struct icl_conn *)kobj_create(&icl_soft_class, M_ICL_SOFT, M_WAITOK | M_ZERO);
1157
1158         STAILQ_INIT(&ic->ic_to_send);
1159         ic->ic_lock = lock;
1160         cv_init(&ic->ic_send_cv, "icl_tx");
1161         cv_init(&ic->ic_receive_cv, "icl_rx");
1162 #ifdef DIAGNOSTIC
1163         refcount_init(&ic->ic_outstanding_pdus, 0);
1164 #endif
1165         ic->ic_max_data_segment_length = ICL_MAX_DATA_SEGMENT_LENGTH;
1166         ic->ic_name = name;
1167         ic->ic_offload = "None";
1168         ic->ic_unmapped = false;
1169
1170         return (ic);
1171 }
1172
1173 void
1174 icl_soft_conn_free(struct icl_conn *ic)
1175 {
1176
1177 #ifdef DIAGNOSTIC
1178         KASSERT(ic->ic_outstanding_pdus == 0,
1179             ("destroying session with %d outstanding PDUs",
1180              ic->ic_outstanding_pdus));
1181 #endif
1182         cv_destroy(&ic->ic_send_cv);
1183         cv_destroy(&ic->ic_receive_cv);
1184         kobj_delete((struct kobj *)ic, M_ICL_SOFT);
1185         refcount_release(&icl_ncons);
1186 }
1187
1188 static int
1189 icl_conn_start(struct icl_conn *ic)
1190 {
1191         size_t minspace;
1192         struct sockopt opt;
1193         int error, one = 1;
1194
1195         ICL_CONN_LOCK(ic);
1196
1197         /*
1198          * XXX: Ugly hack.
1199          */
1200         if (ic->ic_socket == NULL) {
1201                 ICL_CONN_UNLOCK(ic);
1202                 return (EINVAL);
1203         }
1204
1205         ic->ic_receive_state = ICL_CONN_STATE_BHS;
1206         ic->ic_receive_len = sizeof(struct iscsi_bhs);
1207         ic->ic_disconnecting = false;
1208
1209         ICL_CONN_UNLOCK(ic);
1210
1211         /*
1212          * For sendspace, this is required because the current code cannot
1213          * send a PDU in pieces; thus, the minimum buffer size is equal
1214          * to the maximum PDU size.  "+4" is to account for possible padding.
1215          *
1216          * What we should actually do here is to use autoscaling, but set
1217          * some minimal buffer size to "minspace".  I don't know a way to do
1218          * that, though.
1219          */
1220         minspace = sizeof(struct iscsi_bhs) + ic->ic_max_data_segment_length +
1221             ISCSI_HEADER_DIGEST_SIZE + ISCSI_DATA_DIGEST_SIZE + 4;
1222         if (sendspace < minspace) {
1223                 ICL_WARN("kern.icl.sendspace too low; must be at least %zd",
1224                     minspace);
1225                 sendspace = minspace;
1226         }
1227         if (recvspace < minspace) {
1228                 ICL_WARN("kern.icl.recvspace too low; must be at least %zd",
1229                     minspace);
1230                 recvspace = minspace;
1231         }
1232
1233         error = soreserve(ic->ic_socket, sendspace, recvspace);
1234         if (error != 0) {
1235                 ICL_WARN("soreserve failed with error %d", error);
1236                 icl_soft_conn_close(ic);
1237                 return (error);
1238         }
1239         ic->ic_socket->so_snd.sb_flags |= SB_AUTOSIZE;
1240         ic->ic_socket->so_rcv.sb_flags |= SB_AUTOSIZE;
1241
1242         /*
1243          * Disable Nagle.
1244          */
1245         bzero(&opt, sizeof(opt));
1246         opt.sopt_dir = SOPT_SET;
1247         opt.sopt_level = IPPROTO_TCP;
1248         opt.sopt_name = TCP_NODELAY;
1249         opt.sopt_val = &one;
1250         opt.sopt_valsize = sizeof(one);
1251         error = sosetopt(ic->ic_socket, &opt);
1252         if (error != 0) {
1253                 ICL_WARN("disabling TCP_NODELAY failed with error %d", error);
1254                 icl_soft_conn_close(ic);
1255                 return (error);
1256         }
1257
1258         /*
1259          * Register socket upcall, to get notified about incoming PDUs
1260          * and free space to send outgoing ones.
1261          */
1262         SOCKBUF_LOCK(&ic->ic_socket->so_snd);
1263         soupcall_set(ic->ic_socket, SO_SND, icl_soupcall_send, ic);
1264         SOCKBUF_UNLOCK(&ic->ic_socket->so_snd);
1265         SOCKBUF_LOCK(&ic->ic_socket->so_rcv);
1266         soupcall_set(ic->ic_socket, SO_RCV, icl_soupcall_receive, ic);
1267         SOCKBUF_UNLOCK(&ic->ic_socket->so_rcv);
1268
1269         /*
1270          * Start threads.
1271          */
1272         ICL_CONN_LOCK(ic);
1273         ic->ic_send_running = ic->ic_receive_running = true;
1274         ICL_CONN_UNLOCK(ic);
1275         error = kthread_add(icl_send_thread, ic, NULL, NULL, 0, 0, "%stx",
1276             ic->ic_name);
1277         if (error != 0) {
1278                 ICL_WARN("kthread_add(9) failed with error %d", error);
1279                 ICL_CONN_LOCK(ic);
1280                 ic->ic_send_running = ic->ic_receive_running = false;
1281                 cv_signal(&ic->ic_send_cv);
1282                 ICL_CONN_UNLOCK(ic);
1283                 icl_soft_conn_close(ic);
1284                 return (error);
1285         }
1286         error = kthread_add(icl_receive_thread, ic, NULL, NULL, 0, 0, "%srx",
1287             ic->ic_name);
1288         if (error != 0) {
1289                 ICL_WARN("kthread_add(9) failed with error %d", error);
1290                 ICL_CONN_LOCK(ic);
1291                 ic->ic_receive_running = false;
1292                 cv_signal(&ic->ic_send_cv);
1293                 ICL_CONN_UNLOCK(ic);
1294                 icl_soft_conn_close(ic);
1295                 return (error);
1296         }
1297
1298         return (0);
1299 }
1300
1301 int
1302 icl_soft_conn_handoff(struct icl_conn *ic, int fd)
1303 {
1304         struct file *fp;
1305         struct socket *so;
1306         cap_rights_t rights;
1307         int error;
1308
1309         ICL_CONN_LOCK_ASSERT_NOT(ic);
1310
1311 #ifdef ICL_KERNEL_PROXY
1312         /*
1313          * We're transitioning to Full Feature phase, and we don't
1314          * really care.
1315          */
1316         if (fd == 0) {
1317                 ICL_CONN_LOCK(ic);
1318                 if (ic->ic_socket == NULL) {
1319                         ICL_CONN_UNLOCK(ic);
1320                         ICL_WARN("proxy handoff without connect");
1321                         return (EINVAL);
1322                 }
1323                 ICL_CONN_UNLOCK(ic);
1324                 return (0);
1325         }
1326 #endif
1327
1328         /*
1329          * Steal the socket from userland.
1330          */
1331         error = fget(curthread, fd,
1332             cap_rights_init(&rights, CAP_SOCK_CLIENT), &fp);
1333         if (error != 0)
1334                 return (error);
1335         if (fp->f_type != DTYPE_SOCKET) {
1336                 fdrop(fp, curthread);
1337                 return (EINVAL);
1338         }
1339         so = fp->f_data;
1340         if (so->so_type != SOCK_STREAM) {
1341                 fdrop(fp, curthread);
1342                 return (EINVAL);
1343         }
1344
1345         ICL_CONN_LOCK(ic);
1346
1347         if (ic->ic_socket != NULL) {
1348                 ICL_CONN_UNLOCK(ic);
1349                 fdrop(fp, curthread);
1350                 return (EBUSY);
1351         }
1352
1353         ic->ic_socket = fp->f_data;
1354         fp->f_ops = &badfileops;
1355         fp->f_data = NULL;
1356         fdrop(fp, curthread);
1357         ICL_CONN_UNLOCK(ic);
1358
1359         error = icl_conn_start(ic);
1360
1361         return (error);
1362 }
1363
1364 void
1365 icl_soft_conn_close(struct icl_conn *ic)
1366 {
1367         struct icl_pdu *pdu;
1368         struct socket *so;
1369
1370         ICL_CONN_LOCK(ic);
1371
1372         /*
1373          * Wake up the threads, so they can properly terminate.
1374          */
1375         ic->ic_disconnecting = true;
1376         while (ic->ic_receive_running || ic->ic_send_running) {
1377                 cv_signal(&ic->ic_receive_cv);
1378                 cv_signal(&ic->ic_send_cv);
1379                 cv_wait(&ic->ic_send_cv, ic->ic_lock);
1380         }
1381
1382         /* Some other thread could close the connection same time. */
1383         so = ic->ic_socket;
1384         if (so == NULL) {
1385                 ICL_CONN_UNLOCK(ic);
1386                 return;
1387         }
1388         ic->ic_socket = NULL;
1389
1390         /*
1391          * Deregister socket upcalls.
1392          */
1393         ICL_CONN_UNLOCK(ic);
1394         SOCKBUF_LOCK(&so->so_snd);
1395         if (so->so_snd.sb_upcall != NULL)
1396                 soupcall_clear(so, SO_SND);
1397         SOCKBUF_UNLOCK(&so->so_snd);
1398         SOCKBUF_LOCK(&so->so_rcv);
1399         if (so->so_rcv.sb_upcall != NULL)
1400                 soupcall_clear(so, SO_RCV);
1401         SOCKBUF_UNLOCK(&so->so_rcv);
1402         soclose(so);
1403         ICL_CONN_LOCK(ic);
1404
1405         if (ic->ic_receive_pdu != NULL) {
1406                 //ICL_DEBUG("freeing partially received PDU");
1407                 icl_soft_conn_pdu_free(ic, ic->ic_receive_pdu);
1408                 ic->ic_receive_pdu = NULL;
1409         }
1410
1411         /*
1412          * Remove any outstanding PDUs from the send queue.
1413          */
1414         while (!STAILQ_EMPTY(&ic->ic_to_send)) {
1415                 pdu = STAILQ_FIRST(&ic->ic_to_send);
1416                 STAILQ_REMOVE_HEAD(&ic->ic_to_send, ip_next);
1417                 icl_soft_conn_pdu_free(ic, pdu);
1418         }
1419
1420         KASSERT(STAILQ_EMPTY(&ic->ic_to_send),
1421             ("destroying session with non-empty send queue"));
1422         ICL_CONN_UNLOCK(ic);
1423 }
1424
1425 int
1426 icl_soft_conn_task_setup(struct icl_conn *ic, struct icl_pdu *ip,
1427     struct ccb_scsiio *csio, uint32_t *task_tagp, void **prvp)
1428 {
1429
1430         return (0);
1431 }
1432
1433 void
1434 icl_soft_conn_task_done(struct icl_conn *ic, void *prv)
1435 {
1436 }
1437
1438 int
1439 icl_soft_conn_transfer_setup(struct icl_conn *ic, union ctl_io *io,
1440     uint32_t *transfer_tag, void **prvp)
1441 {
1442
1443         return (0);
1444 }
1445
1446 void
1447 icl_soft_conn_transfer_done(struct icl_conn *ic, void *prv)
1448 {
1449 }
1450
1451 static int
1452 icl_soft_limits(struct icl_drv_limits *idl)
1453 {
1454
1455         idl->idl_max_recv_data_segment_length = 128 * 1024;
1456         idl->idl_max_send_data_segment_length = 128 * 1024;
1457         idl->idl_max_burst_length = 262144;
1458         idl->idl_first_burst_length = 65536;
1459
1460         return (0);
1461 }
1462
1463 #ifdef ICL_KERNEL_PROXY
1464 int
1465 icl_soft_conn_connect(struct icl_conn *ic, int domain, int socktype,
1466     int protocol, struct sockaddr *from_sa, struct sockaddr *to_sa)
1467 {
1468
1469         return (icl_soft_proxy_connect(ic, domain, socktype, protocol,
1470             from_sa, to_sa));
1471 }
1472
1473 int
1474 icl_soft_handoff_sock(struct icl_conn *ic, struct socket *so)
1475 {
1476         int error;
1477
1478         ICL_CONN_LOCK_ASSERT_NOT(ic);
1479
1480         if (so->so_type != SOCK_STREAM)
1481                 return (EINVAL);
1482
1483         ICL_CONN_LOCK(ic);
1484         if (ic->ic_socket != NULL) {
1485                 ICL_CONN_UNLOCK(ic);
1486                 return (EBUSY);
1487         }
1488         ic->ic_socket = so;
1489         ICL_CONN_UNLOCK(ic);
1490
1491         error = icl_conn_start(ic);
1492
1493         return (error);
1494 }
1495 #endif /* ICL_KERNEL_PROXY */
1496
1497 static int
1498 icl_soft_load(void)
1499 {
1500         int error;
1501
1502         icl_pdu_zone = uma_zcreate("icl_pdu",
1503             sizeof(struct icl_pdu), NULL, NULL, NULL, NULL,
1504             UMA_ALIGN_PTR, 0);
1505         refcount_init(&icl_ncons, 0);
1506
1507         /*
1508          * The reason we call this "none" is that to the user,
1509          * it's known as "offload driver"; "offload driver: soft"
1510          * doesn't make much sense.
1511          */
1512         error = icl_register("none", false, 0,
1513             icl_soft_limits, icl_soft_new_conn);
1514         KASSERT(error == 0, ("failed to register"));
1515
1516 #if defined(ICL_KERNEL_PROXY) && 0
1517         /*
1518          * Debugging aid for kernel proxy functionality.
1519          */
1520         error = icl_register("proxytest", true, 0,
1521             icl_soft_limits, icl_soft_new_conn);
1522         KASSERT(error == 0, ("failed to register"));
1523 #endif
1524
1525         return (error);
1526 }
1527
1528 static int
1529 icl_soft_unload(void)
1530 {
1531
1532         if (icl_ncons != 0)
1533                 return (EBUSY);
1534
1535         icl_unregister("none", false);
1536 #if defined(ICL_KERNEL_PROXY) && 0
1537         icl_unregister("proxytest", true);
1538 #endif
1539
1540         uma_zdestroy(icl_pdu_zone);
1541
1542         return (0);
1543 }
1544
1545 static int
1546 icl_soft_modevent(module_t mod, int what, void *arg)
1547 {
1548
1549         switch (what) {
1550         case MOD_LOAD:
1551                 return (icl_soft_load());
1552         case MOD_UNLOAD:
1553                 return (icl_soft_unload());
1554         default:
1555                 return (EINVAL);
1556         }
1557 }
1558
1559 moduledata_t icl_soft_data = {
1560         "icl_soft",
1561         icl_soft_modevent,
1562         0
1563 };
1564
1565 DECLARE_MODULE(icl_soft, icl_soft_data, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
1566 MODULE_DEPEND(icl_soft, icl, 1, 1, 1);
1567 MODULE_VERSION(icl_soft, 1);