sys/dev/iscsi/icl_soft.c

   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  */
  30
  31 /*
  32  * Software implementation of iSCSI Common Layer kobj(9) interface.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37
  38 #include <sys/param.h>
  39 #include <sys/capsicum.h>
  40 #include <sys/condvar.h>
  41 #include <sys/conf.h>
  42 #include <sys/file.h>
  43 #include <sys/kernel.h>
  44 #include <sys/kthread.h>
  45 #include <sys/lock.h>
  46 #include <sys/mbuf.h>
  47 #include <sys/mutex.h>
  48 #include <sys/module.h>
  49 #include <sys/protosw.h>
  50 #include <sys/socket.h>
  51 #include <sys/socketvar.h>
  52 #include <sys/sysctl.h>
  53 #include <sys/systm.h>
  54 #include <sys/sx.h>
  55 #include <sys/uio.h>
  56 #include <vm/uma.h>
  57 #include <netinet/in.h>
  58 #include <netinet/tcp.h>
  59
  60 #include <dev/iscsi/icl.h>
  61 #include <dev/iscsi/iscsi_proto.h>
  62 #include <icl_conn_if.h>
  63
  64 static int coalesce = 1;
  65 SYSCTL_INT(_kern_icl, OID_AUTO, coalesce, CTLFLAG_RWTUN,
  66     &coalesce, 0, "Try to coalesce PDUs before sending");
  67 static int partial_receive_len = 128 * 1024;
  68 SYSCTL_INT(_kern_icl, OID_AUTO, partial_receive_len, CTLFLAG_RWTUN,
  69     &partial_receive_len, 0, "Minimum read size for partially received "
  70     "data segment");
  71 static int sendspace = 1048576;
  72 SYSCTL_INT(_kern_icl, OID_AUTO, sendspace, CTLFLAG_RWTUN,
  73     &sendspace, 0, "Default send socket buffer size");
  74 static int recvspace = 1048576;
  75 SYSCTL_INT(_kern_icl, OID_AUTO, recvspace, CTLFLAG_RWTUN,
  76     &recvspace, 0, "Default receive socket buffer size");
  77
  78 static MALLOC_DEFINE(M_ICL_SOFT, "icl_soft", "iSCSI software backend");
  79 static uma_zone_t icl_pdu_zone;
  80
  81 static volatile u_int   icl_ncons;
  82
  83 #define ICL_CONN_LOCK(X)                mtx_lock(X->ic_lock)
  84 #define ICL_CONN_UNLOCK(X)              mtx_unlock(X->ic_lock)
  85 #define ICL_CONN_LOCK_ASSERT(X)         mtx_assert(X->ic_lock, MA_OWNED)
  86 #define ICL_CONN_LOCK_ASSERT_NOT(X)     mtx_assert(X->ic_lock, MA_NOTOWNED)
  87
  88 STAILQ_HEAD(icl_pdu_stailq, icl_pdu);
  89
  90 static icl_conn_new_pdu_t       icl_soft_conn_new_pdu;
  91 static icl_conn_pdu_free_t      icl_soft_conn_pdu_free;
  92 static icl_conn_pdu_data_segment_length_t
  93                                     icl_soft_conn_pdu_data_segment_length;
  94 static icl_conn_pdu_append_data_t       icl_soft_conn_pdu_append_data;
  95 static icl_conn_pdu_get_data_t  icl_soft_conn_pdu_get_data;
  96 static icl_conn_pdu_queue_t     icl_soft_conn_pdu_queue;
  97 static icl_conn_handoff_t       icl_soft_conn_handoff;
  98 static icl_conn_free_t          icl_soft_conn_free;
  99 static icl_conn_close_t         icl_soft_conn_close;
 100 static icl_conn_task_setup_t    icl_soft_conn_task_setup;
 101 static icl_conn_task_done_t     icl_soft_conn_task_done;
 102 static icl_conn_transfer_setup_t        icl_soft_conn_transfer_setup;
 103 static icl_conn_transfer_done_t icl_soft_conn_transfer_done;
 104
 105 static kobj_method_t icl_soft_methods[] = {
 106         KOBJMETHOD(icl_conn_new_pdu, icl_soft_conn_new_pdu),
 107         KOBJMETHOD(icl_conn_pdu_free, icl_soft_conn_pdu_free),
 108         KOBJMETHOD(icl_conn_pdu_data_segment_length,
 109             icl_soft_conn_pdu_data_segment_length),
 110         KOBJMETHOD(icl_conn_pdu_append_data, icl_soft_conn_pdu_append_data),
 111         KOBJMETHOD(icl_conn_pdu_get_data, icl_soft_conn_pdu_get_data),
 112         KOBJMETHOD(icl_conn_pdu_queue, icl_soft_conn_pdu_queue),
 113         KOBJMETHOD(icl_conn_handoff, icl_soft_conn_handoff),
 114         KOBJMETHOD(icl_conn_free, icl_soft_conn_free),
 115         KOBJMETHOD(icl_conn_close, icl_soft_conn_close),
 116         KOBJMETHOD(icl_conn_task_setup, icl_soft_conn_task_setup),
 117         KOBJMETHOD(icl_conn_task_done, icl_soft_conn_task_done),
 118         KOBJMETHOD(icl_conn_transfer_setup, icl_soft_conn_transfer_setup),
 119         KOBJMETHOD(icl_conn_transfer_done, icl_soft_conn_transfer_done),
 120         { 0, 0 }
 121 };
 122
 123 DEFINE_CLASS(icl_soft, icl_soft_methods, sizeof(struct icl_conn));
 124
 125 static void
 126 icl_conn_fail(struct icl_conn *ic)
 127 {
 128         if (ic->ic_socket == NULL)
 129                 return;
 130
 131         /*
 132          * XXX
 133          */
 134         ic->ic_socket->so_error = EDOOFUS;
 135         (ic->ic_error)(ic);
 136 }
 137
 138 static struct mbuf *
 139 icl_conn_receive(struct icl_conn *ic, size_t len)
 140 {
 141         struct uio uio;
 142         struct socket *so;
 143         struct mbuf *m;
 144         int error, flags;
 145
 146         so = ic->ic_socket;
 147
 148         memset(&uio, 0, sizeof(uio));
 149         uio.uio_resid = len;
 150
 151         flags = MSG_DONTWAIT;
 152         error = soreceive(so, NULL, &uio, &m, NULL, &flags);
 153         if (error != 0) {
 154                 ICL_DEBUG("soreceive error %d", error);
 155                 return (NULL);
 156         }
 157         if (uio.uio_resid != 0) {
 158                 m_freem(m);
 159                 ICL_DEBUG("short read");
 160                 return (NULL);
 161         }
 162
 163         return (m);
 164 }
 165
 166 static struct icl_pdu *
 167 icl_pdu_new_empty(struct icl_conn *ic, int flags)
 168 {
 169         struct icl_pdu *ip;
 170
 171 #ifdef DIAGNOSTIC
 172         refcount_acquire(&ic->ic_outstanding_pdus);
 173 #endif
 174         ip = uma_zalloc(icl_pdu_zone, flags | M_ZERO);
 175         if (ip == NULL) {
 176                 ICL_WARN("failed to allocate %zd bytes", sizeof(*ip));
 177 #ifdef DIAGNOSTIC
 178                 refcount_release(&ic->ic_outstanding_pdus);
 179 #endif
 180                 return (NULL);
 181         }
 182
 183         ip->ip_conn = ic;
 184
 185         return (ip);
 186 }
 187
 188 static void
 189 icl_pdu_free(struct icl_pdu *ip)
 190 {
 191         struct icl_conn *ic;
 192
 193         ic = ip->ip_conn;
 194
 195         m_freem(ip->ip_bhs_mbuf);
 196         m_freem(ip->ip_ahs_mbuf);
 197         m_freem(ip->ip_data_mbuf);
 198         uma_zfree(icl_pdu_zone, ip);
 199 #ifdef DIAGNOSTIC
 200         refcount_release(&ic->ic_outstanding_pdus);
 201 #endif
 202 }
 203
 204 void
 205 icl_soft_conn_pdu_free(struct icl_conn *ic, struct icl_pdu *ip)
 206 {
 207
 208         icl_pdu_free(ip);
 209 }
 210
 211 /*
 212  * Allocate icl_pdu with empty BHS to fill up by the caller.
 213  */
 214 struct icl_pdu *
 215 icl_soft_conn_new_pdu(struct icl_conn *ic, int flags)
 216 {
 217         struct icl_pdu *ip;
 218
 219         ip = icl_pdu_new_empty(ic, flags);
 220         if (ip == NULL)
 221                 return (NULL);
 222
 223         ip->ip_bhs_mbuf = m_getm2(NULL, sizeof(struct iscsi_bhs),
 224             flags, MT_DATA, M_PKTHDR);
 225         if (ip->ip_bhs_mbuf == NULL) {
 226                 ICL_WARN("failed to allocate %zd bytes", sizeof(*ip));
 227                 icl_pdu_free(ip);
 228                 return (NULL);
 229         }
 230         ip->ip_bhs = mtod(ip->ip_bhs_mbuf, struct iscsi_bhs *);
 231         memset(ip->ip_bhs, 0, sizeof(struct iscsi_bhs));
 232         ip->ip_bhs_mbuf->m_len = sizeof(struct iscsi_bhs);
 233
 234         return (ip);
 235 }
 236
 237 static int
 238 icl_pdu_ahs_length(const struct icl_pdu *request)
 239 {
 240
 241         return (request->ip_bhs->bhs_total_ahs_len * 4);
 242 }
 243
 244 static size_t
 245 icl_pdu_data_segment_length(const struct icl_pdu *request)
 246 {
 247         uint32_t len = 0;
 248
 249         len += request->ip_bhs->bhs_data_segment_len[0];
 250         len <<= 8;
 251         len += request->ip_bhs->bhs_data_segment_len[1];
 252         len <<= 8;
 253         len += request->ip_bhs->bhs_data_segment_len[2];
 254
 255         return (len);
 256 }
 257
 258 size_t
 259 icl_soft_conn_pdu_data_segment_length(struct icl_conn *ic,
 260     const struct icl_pdu *request)
 261 {
 262
 263         return (icl_pdu_data_segment_length(request));
 264 }
 265
 266 static void
 267 icl_pdu_set_data_segment_length(struct icl_pdu *response, uint32_t len)
 268 {
 269
 270         response->ip_bhs->bhs_data_segment_len[2] = len;
 271         response->ip_bhs->bhs_data_segment_len[1] = len >> 8;
 272         response->ip_bhs->bhs_data_segment_len[0] = len >> 16;
 273 }
 274
 275 static size_t
 276 icl_pdu_padding(const struct icl_pdu *ip)
 277 {
 278
 279         if ((ip->ip_data_len % 4) != 0)
 280                 return (4 - (ip->ip_data_len % 4));
 281
 282         return (0);
 283 }
 284
 285 static size_t
 286 icl_pdu_size(const struct icl_pdu *response)
 287 {
 288         size_t len;
 289
 290         KASSERT(response->ip_ahs_len == 0, ("responding with AHS"));
 291
 292         len = sizeof(struct iscsi_bhs) + response->ip_data_len +
 293             icl_pdu_padding(response);
 294         if (response->ip_conn->ic_header_crc32c)
 295                 len += ISCSI_HEADER_DIGEST_SIZE;
 296         if (response->ip_data_len != 0 && response->ip_conn->ic_data_crc32c)
 297                 len += ISCSI_DATA_DIGEST_SIZE;
 298
 299         return (len);
 300 }
 301
 302 static int
 303 icl_pdu_receive_bhs(struct icl_pdu *request, size_t *availablep)
 304 {
 305         struct mbuf *m;
 306
 307         m = icl_conn_receive(request->ip_conn, sizeof(struct iscsi_bhs));
 308         if (m == NULL) {
 309                 ICL_DEBUG("failed to receive BHS");
 310                 return (-1);
 311         }
 312
 313         request->ip_bhs_mbuf = m_pullup(m, sizeof(struct iscsi_bhs));
 314         if (request->ip_bhs_mbuf == NULL) {
 315                 ICL_WARN("m_pullup failed");
 316                 return (-1);
 317         }
 318         request->ip_bhs = mtod(request->ip_bhs_mbuf, struct iscsi_bhs *);
 319
 320         /*
 321          * XXX: For architectures with strict alignment requirements
 322          *      we may need to allocate ip_bhs and copy the data into it.
 323          *      For some reason, though, not doing this doesn't seem
 324          *      to cause problems; tested on sparc64.
 325          */
 326
 327         *availablep -= sizeof(struct iscsi_bhs);
 328         return (0);
 329 }
 330
 331 static int
 332 icl_pdu_receive_ahs(struct icl_pdu *request, size_t *availablep)
 333 {
 334
 335         request->ip_ahs_len = icl_pdu_ahs_length(request);
 336         if (request->ip_ahs_len == 0)
 337                 return (0);
 338
 339         request->ip_ahs_mbuf = icl_conn_receive(request->ip_conn,
 340             request->ip_ahs_len);
 341         if (request->ip_ahs_mbuf == NULL) {
 342                 ICL_DEBUG("failed to receive AHS");
 343                 return (-1);
 344         }
 345
 346         *availablep -= request->ip_ahs_len;
 347         return (0);
 348 }
 349
 350 static uint32_t
 351 icl_mbuf_to_crc32c(const struct mbuf *m0)
 352 {
 353         uint32_t digest = 0xffffffff;
 354         const struct mbuf *m;
 355
 356         for (m = m0; m != NULL; m = m->m_next)
 357                 digest = calculate_crc32c(digest,
 358                     mtod(m, const void *), m->m_len);
 359
 360         digest = digest ^ 0xffffffff;
 361
 362         return (digest);
 363 }
 364
 365 static int
 366 icl_pdu_check_header_digest(struct icl_pdu *request, size_t *availablep)
 367 {
 368         struct mbuf *m;
 369         uint32_t received_digest, valid_digest;
 370
 371         if (request->ip_conn->ic_header_crc32c == false)
 372                 return (0);
 373
 374         m = icl_conn_receive(request->ip_conn, ISCSI_HEADER_DIGEST_SIZE);
 375         if (m == NULL) {
 376                 ICL_DEBUG("failed to receive header digest");
 377                 return (-1);
 378         }
 379
 380         CTASSERT(sizeof(received_digest) == ISCSI_HEADER_DIGEST_SIZE);
 381         m_copydata(m, 0, ISCSI_HEADER_DIGEST_SIZE, (void *)&received_digest);
 382         m_freem(m);
 383
 384         *availablep -= ISCSI_HEADER_DIGEST_SIZE;
 385
 386         /*
 387          * XXX: Handle AHS.
 388          */
 389         valid_digest = icl_mbuf_to_crc32c(request->ip_bhs_mbuf);
 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         struct mbuf *m;
 524         uint32_t received_digest, valid_digest;
 525
 526         if (request->ip_conn->ic_data_crc32c == false)
 527                 return (0);
 528
 529         if (request->ip_data_len == 0)
 530                 return (0);
 531
 532         m = icl_conn_receive(request->ip_conn, ISCSI_DATA_DIGEST_SIZE);
 533         if (m == NULL) {
 534                 ICL_DEBUG("failed to receive data digest");
 535                 return (-1);
 536         }
 537
 538         CTASSERT(sizeof(received_digest) == ISCSI_DATA_DIGEST_SIZE);
 539         m_copydata(m, 0, ISCSI_DATA_DIGEST_SIZE, (void *)&received_digest);
 540         m_freem(m);
 541
 542         *availablep -= ISCSI_DATA_DIGEST_SIZE;
 543
 544         /*
 545          * Note that ip_data_mbuf also contains padding; since digest
 546          * calculation is supposed to include that, we iterate over
 547          * the entire ip_data_mbuf chain, not just ip_data_len bytes of it.
 548          */
 549         valid_digest = icl_mbuf_to_crc32c(request->ip_data_mbuf);
 550         if (received_digest != valid_digest) {
 551                 ICL_WARN("data digest check failed; got 0x%x, "
 552                     "should be 0x%x", received_digest, valid_digest);
 553                 return (-1);
 554         }
 555
 556         return (0);
 557 }
 558
 559 /*
 560  * Somewhat contrary to the name, this attempts to receive only one
 561  * "part" of PDU at a time; call it repeatedly until it returns non-NULL.
 562  */
 563 static struct icl_pdu *
 564 icl_conn_receive_pdu(struct icl_conn *ic, size_t *availablep)
 565 {
 566         struct icl_pdu *request;
 567         struct socket *so;
 568         size_t len;
 569         int error;
 570         bool more_needed;
 571
 572         so = ic->ic_socket;
 573
 574         if (ic->ic_receive_state == ICL_CONN_STATE_BHS) {
 575                 KASSERT(ic->ic_receive_pdu == NULL,
 576                     ("ic->ic_receive_pdu != NULL"));
 577                 request = icl_pdu_new_empty(ic, M_NOWAIT);
 578                 if (request == NULL) {
 579                         ICL_DEBUG("failed to allocate PDU; "
 580                             "dropping connection");
 581                         icl_conn_fail(ic);
 582                         return (NULL);
 583                 }
 584                 ic->ic_receive_pdu = request;
 585         } else {
 586                 KASSERT(ic->ic_receive_pdu != NULL,
 587                     ("ic->ic_receive_pdu == NULL"));
 588                 request = ic->ic_receive_pdu;
 589         }
 590
 591         if (*availablep < ic->ic_receive_len) {
 592 #if 0
 593                 ICL_DEBUG("not enough data; need %zd, "
 594                     "have %zd", ic->ic_receive_len, *availablep);
 595 #endif
 596                 return (NULL);
 597         }
 598
 599         switch (ic->ic_receive_state) {
 600         case ICL_CONN_STATE_BHS:
 601                 //ICL_DEBUG("receiving BHS");
 602                 error = icl_pdu_receive_bhs(request, availablep);
 603                 if (error != 0) {
 604                         ICL_DEBUG("failed to receive BHS; "
 605                             "dropping connection");
 606                         break;
 607                 }
 608
 609                 /*
 610                  * We don't enforce any limit for AHS length;
 611                  * its length is stored in 8 bit field.
 612                  */
 613
 614                 len = icl_pdu_data_segment_length(request);
 615                 if (len > ic->ic_max_data_segment_length) {
 616                         ICL_WARN("received data segment "
 617                             "length %zd is larger than negotiated "
 618                             "MaxDataSegmentLength %zd; "
 619                             "dropping connection",
 620                             len, ic->ic_max_data_segment_length);
 621                         error = EINVAL;
 622                         break;
 623                 }
 624
 625                 ic->ic_receive_state = ICL_CONN_STATE_AHS;
 626                 ic->ic_receive_len = icl_pdu_ahs_length(request);
 627                 break;
 628
 629         case ICL_CONN_STATE_AHS:
 630                 //ICL_DEBUG("receiving AHS");
 631                 error = icl_pdu_receive_ahs(request, availablep);
 632                 if (error != 0) {
 633                         ICL_DEBUG("failed to receive AHS; "
 634                             "dropping connection");
 635                         break;
 636                 }
 637                 ic->ic_receive_state = ICL_CONN_STATE_HEADER_DIGEST;
 638                 if (ic->ic_header_crc32c == false)
 639                         ic->ic_receive_len = 0;
 640                 else
 641                         ic->ic_receive_len = ISCSI_HEADER_DIGEST_SIZE;
 642                 break;
 643
 644         case ICL_CONN_STATE_HEADER_DIGEST:
 645                 //ICL_DEBUG("receiving header digest");
 646                 error = icl_pdu_check_header_digest(request, availablep);
 647                 if (error != 0) {
 648                         ICL_DEBUG("header digest failed; "
 649                             "dropping connection");
 650                         break;
 651                 }
 652
 653                 ic->ic_receive_state = ICL_CONN_STATE_DATA;
 654                 ic->ic_receive_len =
 655                     icl_pdu_data_segment_receive_len(request);
 656                 break;
 657
 658         case ICL_CONN_STATE_DATA:
 659                 //ICL_DEBUG("receiving data segment");
 660                 error = icl_pdu_receive_data_segment(request, availablep,
 661                     &more_needed);
 662                 if (error != 0) {
 663                         ICL_DEBUG("failed to receive data segment;"
 664                             "dropping connection");
 665                         break;
 666                 }
 667
 668                 if (more_needed)
 669                         break;
 670
 671                 ic->ic_receive_state = ICL_CONN_STATE_DATA_DIGEST;
 672                 if (request->ip_data_len == 0 || ic->ic_data_crc32c == false)
 673                         ic->ic_receive_len = 0;
 674                 else
 675                         ic->ic_receive_len = ISCSI_DATA_DIGEST_SIZE;
 676                 break;
 677
 678         case ICL_CONN_STATE_DATA_DIGEST:
 679                 //ICL_DEBUG("receiving data digest");
 680                 error = icl_pdu_check_data_digest(request, availablep);
 681                 if (error != 0) {
 682                         ICL_DEBUG("data digest failed; "
 683                             "dropping connection");
 684                         break;
 685                 }
 686
 687                 /*
 688                  * We've received complete PDU; reset the receive state machine
 689                  * and return the PDU.
 690                  */
 691                 ic->ic_receive_state = ICL_CONN_STATE_BHS;
 692                 ic->ic_receive_len = sizeof(struct iscsi_bhs);
 693                 ic->ic_receive_pdu = NULL;
 694                 return (request);
 695
 696         default:
 697                 panic("invalid ic_receive_state %d\n", ic->ic_receive_state);
 698         }
 699
 700         if (error != 0) {
 701                 /*
 702                  * Don't free the PDU; it's pointed to by ic->ic_receive_pdu
 703                  * and will get freed in icl_soft_conn_close().
 704                  */
 705                 icl_conn_fail(ic);
 706         }
 707
 708         return (NULL);
 709 }
 710
 711 static void
 712 icl_conn_receive_pdus(struct icl_conn *ic, size_t available)
 713 {
 714         struct icl_pdu *response;
 715         struct socket *so;
 716
 717         so = ic->ic_socket;
 718
 719         /*
 720          * This can never happen; we're careful to only mess with ic->ic_socket
 721          * pointer when the send/receive threads are not running.
 722          */
 723         KASSERT(so != NULL, ("NULL socket"));
 724
 725         for (;;) {
 726                 if (ic->ic_disconnecting)
 727                         return;
 728
 729                 if (so->so_error != 0) {
 730                         ICL_DEBUG("connection error %d; "
 731                             "dropping connection", so->so_error);
 732                         icl_conn_fail(ic);
 733                         return;
 734                 }
 735
 736                 /*
 737                  * Loop until we have a complete PDU or there is not enough
 738                  * data in the socket buffer.
 739                  */
 740                 if (available < ic->ic_receive_len) {
 741 #if 0
 742                         ICL_DEBUG("not enough data; have %zd, "
 743                             "need %zd", available,
 744                             ic->ic_receive_len);
 745 #endif
 746                         return;
 747                 }
 748
 749                 response = icl_conn_receive_pdu(ic, &available);
 750                 if (response == NULL)
 751                         continue;
 752
 753                 if (response->ip_ahs_len > 0) {
 754                         ICL_WARN("received PDU with unsupported "
 755                             "AHS; opcode 0x%x; dropping connection",
 756                             response->ip_bhs->bhs_opcode);
 757                         icl_pdu_free(response);
 758                         icl_conn_fail(ic);
 759                         return;
 760                 }
 761
 762                 (ic->ic_receive)(response);
 763         }
 764 }
 765
 766 static void
 767 icl_receive_thread(void *arg)
 768 {
 769         struct icl_conn *ic;
 770         size_t available;
 771         struct socket *so;
 772
 773         ic = arg;
 774         so = ic->ic_socket;
 775
 776         for (;;) {
 777                 if (ic->ic_disconnecting) {
 778                         //ICL_DEBUG("terminating");
 779                         break;
 780                 }
 781
 782                 /*
 783                  * Set the low watermark, to be checked by
 784                  * soreadable() in icl_soupcall_receive()
 785                  * to avoid unneccessary wakeups until there
 786                  * is enough data received to read the PDU.
 787                  */
 788                 SOCKBUF_LOCK(&so->so_rcv);
 789                 available = sbavail(&so->so_rcv);
 790                 if (available < ic->ic_receive_len) {
 791                         so->so_rcv.sb_lowat = ic->ic_receive_len;
 792                         cv_wait(&ic->ic_receive_cv, &so->so_rcv.sb_mtx);
 793                 } else
 794                         so->so_rcv.sb_lowat = so->so_rcv.sb_hiwat + 1;
 795                 SOCKBUF_UNLOCK(&so->so_rcv);
 796
 797                 icl_conn_receive_pdus(ic, available);
 798         }
 799
 800         ICL_CONN_LOCK(ic);
 801         ic->ic_receive_running = false;
 802         cv_signal(&ic->ic_send_cv);
 803         ICL_CONN_UNLOCK(ic);
 804         kthread_exit();
 805 }
 806
 807 static int
 808 icl_soupcall_receive(struct socket *so, void *arg, int waitflag)
 809 {
 810         struct icl_conn *ic;
 811
 812         if (!soreadable(so))
 813                 return (SU_OK);
 814
 815         ic = arg;
 816         cv_signal(&ic->ic_receive_cv);
 817         return (SU_OK);
 818 }
 819
 820 static int
 821 icl_pdu_finalize(struct icl_pdu *request)
 822 {
 823         size_t padding, pdu_len;
 824         uint32_t digest, zero = 0;
 825         int ok;
 826         struct icl_conn *ic;
 827
 828         ic = request->ip_conn;
 829
 830         icl_pdu_set_data_segment_length(request, request->ip_data_len);
 831
 832         pdu_len = icl_pdu_size(request);
 833
 834         if (ic->ic_header_crc32c) {
 835                 digest = icl_mbuf_to_crc32c(request->ip_bhs_mbuf);
 836                 ok = m_append(request->ip_bhs_mbuf, sizeof(digest),
 837                     (void *)&digest);
 838                 if (ok != 1) {
 839                         ICL_WARN("failed to append header digest");
 840                         return (1);
 841                 }
 842         }
 843
 844         if (request->ip_data_len != 0) {
 845                 padding = icl_pdu_padding(request);
 846                 if (padding > 0) {
 847                         ok = m_append(request->ip_data_mbuf, padding,
 848                             (void *)&zero);
 849                         if (ok != 1) {
 850                                 ICL_WARN("failed to append padding");
 851                                 return (1);
 852                         }
 853                 }
 854
 855                 if (ic->ic_data_crc32c) {
 856                         digest = icl_mbuf_to_crc32c(request->ip_data_mbuf);
 857
 858                         ok = m_append(request->ip_data_mbuf, sizeof(digest),
 859                             (void *)&digest);
 860                         if (ok != 1) {
 861                                 ICL_WARN("failed to append data digest");
 862                                 return (1);
 863                         }
 864                 }
 865
 866                 m_cat(request->ip_bhs_mbuf, request->ip_data_mbuf);
 867                 request->ip_data_mbuf = NULL;
 868         }
 869
 870         request->ip_bhs_mbuf->m_pkthdr.len = pdu_len;
 871
 872         return (0);
 873 }
 874
 875 static void
 876 icl_conn_send_pdus(struct icl_conn *ic, struct icl_pdu_stailq *queue)
 877 {
 878         struct icl_pdu *request, *request2;
 879         struct socket *so;
 880         size_t available, size, size2;
 881         int coalesced, error;
 882
 883         ICL_CONN_LOCK_ASSERT_NOT(ic);
 884
 885         so = ic->ic_socket;
 886
 887         SOCKBUF_LOCK(&so->so_snd);
 888         /*
 889          * Check how much space do we have for transmit.  We can't just
 890          * call sosend() and retry when we get EWOULDBLOCK or EMSGSIZE,
 891          * as it always frees the mbuf chain passed to it, even in case
 892          * of error.
 893          */
 894         available = sbspace(&so->so_snd);
 895
 896         /*
 897          * Notify the socket upcall that we don't need wakeups
 898          * for the time being.
 899          */
 900         so->so_snd.sb_lowat = so->so_snd.sb_hiwat + 1;
 901         SOCKBUF_UNLOCK(&so->so_snd);
 902
 903         while (!STAILQ_EMPTY(queue)) {
 904                 request = STAILQ_FIRST(queue);
 905                 size = icl_pdu_size(request);
 906                 if (available < size) {
 907
 908                         /*
 909                          * Set the low watermark, to be checked by
 910                          * sowriteable() in icl_soupcall_send()
 911                          * to avoid unneccessary wakeups until there
 912                          * is enough space for the PDU to fit.
 913                          */
 914                         SOCKBUF_LOCK(&so->so_snd);
 915                         available = sbspace(&so->so_snd);
 916                         if (available < size) {
 917 #if 1
 918                                 ICL_DEBUG("no space to send; "
 919                                     "have %zd, need %zd",
 920                                     available, size);
 921 #endif
 922                                 so->so_snd.sb_lowat = size;
 923                                 SOCKBUF_UNLOCK(&so->so_snd);
 924                                 return;
 925                         }
 926                         SOCKBUF_UNLOCK(&so->so_snd);
 927                 }
 928                 STAILQ_REMOVE_HEAD(queue, ip_next);
 929                 error = icl_pdu_finalize(request);
 930                 if (error != 0) {
 931                         ICL_DEBUG("failed to finalize PDU; "
 932                             "dropping connection");
 933                         icl_conn_fail(ic);
 934                         icl_pdu_free(request);
 935                         return;
 936                 }
 937                 if (coalesce) {
 938                         coalesced = 1;
 939                         for (;;) {
 940                                 request2 = STAILQ_FIRST(queue);
 941                                 if (request2 == NULL)
 942                                         break;
 943                                 size2 = icl_pdu_size(request2);
 944                                 if (available < size + size2)
 945                                         break;
 946                                 STAILQ_REMOVE_HEAD(queue, ip_next);
 947                                 error = icl_pdu_finalize(request2);
 948                                 if (error != 0) {
 949                                         ICL_DEBUG("failed to finalize PDU; "
 950                                             "dropping connection");
 951                                         icl_conn_fail(ic);
 952                                         icl_pdu_free(request);
 953                                         icl_pdu_free(request2);
 954                                         return;
 955                                 }
 956                                 m_cat(request->ip_bhs_mbuf, request2->ip_bhs_mbuf);
 957                                 request2->ip_bhs_mbuf = NULL;
 958                                 request->ip_bhs_mbuf->m_pkthdr.len += size2;
 959                                 size += size2;
 960                                 STAILQ_REMOVE_AFTER(queue, request, ip_next);
 961                                 icl_pdu_free(request2);
 962                                 coalesced++;
 963                         }
 964 #if 0
 965                         if (coalesced > 1) {
 966                                 ICL_DEBUG("coalesced %d PDUs into %zd bytes",
 967                                     coalesced, size);
 968                         }
 969 #endif
 970                 }
 971                 available -= size;
 972                 error = sosend(so, NULL, NULL, request->ip_bhs_mbuf,
 973                     NULL, MSG_DONTWAIT, curthread);
 974                 request->ip_bhs_mbuf = NULL; /* Sosend consumes the mbuf. */
 975                 if (error != 0) {
 976                         ICL_DEBUG("failed to send PDU, error %d; "
 977                             "dropping connection", error);
 978                         icl_conn_fail(ic);
 979                         icl_pdu_free(request);
 980                         return;
 981                 }
 982                 icl_pdu_free(request);
 983         }
 984 }
 985
 986 static void
 987 icl_send_thread(void *arg)
 988 {
 989         struct icl_conn *ic;
 990         struct icl_pdu_stailq queue;
 991
 992         ic = arg;
 993
 994         STAILQ_INIT(&queue);
 995
 996         ICL_CONN_LOCK(ic);
 997         for (;;) {
 998                 for (;;) {
 999                         /*
1000                          * If the local queue is empty, populate it from
1001                          * the main one.  This way the icl_conn_send_pdus()
1002                          * can go through all the queued PDUs without holding
1003                          * any locks.
1004                          */
1005                         if (STAILQ_EMPTY(&queue))
1006                                 STAILQ_SWAP(&ic->ic_to_send, &queue, icl_pdu);
1007
1008                         ic->ic_check_send_space = false;
1009                         ICL_CONN_UNLOCK(ic);
1010                         icl_conn_send_pdus(ic, &queue);
1011                         ICL_CONN_LOCK(ic);
1012
1013                         /*
1014                          * The icl_soupcall_send() was called since the last
1015                          * call to sbspace(); go around;
1016                          */
1017                         if (ic->ic_check_send_space)
1018                                 continue;
1019
1020                         /*
1021                          * Local queue is empty, but we still have PDUs
1022                          * in the main one; go around.
1023                          */
1024                         if (STAILQ_EMPTY(&queue) &&
1025                             !STAILQ_EMPTY(&ic->ic_to_send))
1026                                 continue;
1027
1028                         /*
1029                          * There might be some stuff in the local queue,
1030                          * which didn't get sent due to not having enough send
1031                          * space.  Wait for socket upcall.
1032                          */
1033                         break;
1034                 }
1035
1036                 if (ic->ic_disconnecting) {
1037                         //ICL_DEBUG("terminating");
1038                         break;
1039                 }
1040
1041                 cv_wait(&ic->ic_send_cv, ic->ic_lock);
1042         }
1043
1044         /*
1045          * We're exiting; move PDUs back to the main queue, so they can
1046          * get freed properly.  At this point ordering doesn't matter.
1047          */
1048         STAILQ_CONCAT(&ic->ic_to_send, &queue);
1049
1050         ic->ic_send_running = false;
1051         cv_signal(&ic->ic_send_cv);
1052         ICL_CONN_UNLOCK(ic);
1053         kthread_exit();
1054 }
1055
1056 static int
1057 icl_soupcall_send(struct socket *so, void *arg, int waitflag)
1058 {
1059         struct icl_conn *ic;
1060
1061         if (!sowriteable(so))
1062                 return (SU_OK);
1063
1064         ic = arg;
1065
1066         ICL_CONN_LOCK(ic);
1067         ic->ic_check_send_space = true;
1068         ICL_CONN_UNLOCK(ic);
1069
1070         cv_signal(&ic->ic_send_cv);
1071
1072         return (SU_OK);
1073 }
1074
1075 static int
1076 icl_pdu_append_data(struct icl_pdu *request, const void *addr, size_t len,
1077     int flags)
1078 {
1079         struct mbuf *mb, *newmb;
1080         size_t copylen, off = 0;
1081
1082         KASSERT(len > 0, ("len == 0"));
1083
1084         newmb = m_getm2(NULL, len, flags, MT_DATA, M_PKTHDR);
1085         if (newmb == NULL) {
1086                 ICL_WARN("failed to allocate mbuf for %zd bytes", len);
1087                 return (ENOMEM);
1088         }
1089
1090         for (mb = newmb; mb != NULL; mb = mb->m_next) {
1091                 copylen = min(M_TRAILINGSPACE(mb), len - off);
1092                 memcpy(mtod(mb, char *), (const char *)addr + off, copylen);
1093                 mb->m_len = copylen;
1094                 off += copylen;
1095         }
1096         KASSERT(off == len, ("%s: off != len", __func__));
1097
1098         if (request->ip_data_mbuf == NULL) {
1099                 request->ip_data_mbuf = newmb;
1100                 request->ip_data_len = len;
1101         } else {
1102                 m_cat(request->ip_data_mbuf, newmb);
1103                 request->ip_data_len += len;
1104         }
1105
1106         return (0);
1107 }
1108
1109 int
1110 icl_soft_conn_pdu_append_data(struct icl_conn *ic, struct icl_pdu *request,
1111     const void *addr, size_t len, int flags)
1112 {
1113
1114         return (icl_pdu_append_data(request, addr, len, flags));
1115 }
1116
1117 static void
1118 icl_pdu_get_data(struct icl_pdu *ip, size_t off, void *addr, size_t len)
1119 {
1120
1121         m_copydata(ip->ip_data_mbuf, off, len, addr);
1122 }
1123
1124 void
1125 icl_soft_conn_pdu_get_data(struct icl_conn *ic, struct icl_pdu *ip,
1126     size_t off, void *addr, size_t len)
1127 {
1128
1129         return (icl_pdu_get_data(ip, off, addr, len));
1130 }
1131
1132 static void
1133 icl_pdu_queue(struct icl_pdu *ip)
1134 {
1135         struct icl_conn *ic;
1136
1137         ic = ip->ip_conn;
1138
1139         ICL_CONN_LOCK_ASSERT(ic);
1140
1141         if (ic->ic_disconnecting || ic->ic_socket == NULL) {
1142                 ICL_DEBUG("icl_pdu_queue on closed connection");
1143                 icl_pdu_free(ip);
1144                 return;
1145         }
1146
1147         if (!STAILQ_EMPTY(&ic->ic_to_send)) {
1148                 STAILQ_INSERT_TAIL(&ic->ic_to_send, ip, ip_next);
1149                 /*
1150                  * If the queue is not empty, someone else had already
1151                  * signaled the send thread; no need to do that again,
1152                  * just return.
1153                  */
1154                 return;
1155         }
1156
1157         STAILQ_INSERT_TAIL(&ic->ic_to_send, ip, ip_next);
1158         cv_signal(&ic->ic_send_cv);
1159 }
1160
1161 void
1162 icl_soft_conn_pdu_queue(struct icl_conn *ic, struct icl_pdu *ip)
1163 {
1164
1165         icl_pdu_queue(ip);
1166 }
1167
1168 static struct icl_conn *
1169 icl_soft_new_conn(const char *name, struct mtx *lock)
1170 {
1171         struct icl_conn *ic;
1172
1173         refcount_acquire(&icl_ncons);
1174
1175         ic = (struct icl_conn *)kobj_create(&icl_soft_class, M_ICL_SOFT, M_WAITOK | M_ZERO);
1176
1177         STAILQ_INIT(&ic->ic_to_send);
1178         ic->ic_lock = lock;
1179         cv_init(&ic->ic_send_cv, "icl_tx");
1180         cv_init(&ic->ic_receive_cv, "icl_rx");
1181 #ifdef DIAGNOSTIC
1182         refcount_init(&ic->ic_outstanding_pdus, 0);
1183 #endif
1184         ic->ic_max_data_segment_length = ICL_MAX_DATA_SEGMENT_LENGTH;
1185         ic->ic_name = name;
1186         ic->ic_offload = "None";
1187
1188         return (ic);
1189 }
1190
1191 void
1192 icl_soft_conn_free(struct icl_conn *ic)
1193 {
1194
1195         cv_destroy(&ic->ic_send_cv);
1196         cv_destroy(&ic->ic_receive_cv);
1197         kobj_delete((struct kobj *)ic, M_ICL_SOFT);
1198         refcount_release(&icl_ncons);
1199 }
1200
1201 static int
1202 icl_conn_start(struct icl_conn *ic)
1203 {
1204         size_t minspace;
1205         struct sockopt opt;
1206         int error, one = 1;
1207
1208         ICL_CONN_LOCK(ic);
1209
1210         /*
1211          * XXX: Ugly hack.
1212          */
1213         if (ic->ic_socket == NULL) {
1214                 ICL_CONN_UNLOCK(ic);
1215                 return (EINVAL);
1216         }
1217
1218         ic->ic_receive_state = ICL_CONN_STATE_BHS;
1219         ic->ic_receive_len = sizeof(struct iscsi_bhs);
1220         ic->ic_disconnecting = false;
1221
1222         ICL_CONN_UNLOCK(ic);
1223
1224         /*
1225          * For sendspace, this is required because the current code cannot
1226          * send a PDU in pieces; thus, the minimum buffer size is equal
1227          * to the maximum PDU size.  "+4" is to account for possible padding.
1228          *
1229          * What we should actually do here is to use autoscaling, but set
1230          * some minimal buffer size to "minspace".  I don't know a way to do
1231          * that, though.
1232          */
1233         minspace = sizeof(struct iscsi_bhs) + ic->ic_max_data_segment_length +
1234             ISCSI_HEADER_DIGEST_SIZE + ISCSI_DATA_DIGEST_SIZE + 4;
1235         if (sendspace < minspace) {
1236                 ICL_WARN("kern.icl.sendspace too low; must be at least %zd",
1237                     minspace);
1238                 sendspace = minspace;
1239         }
1240         if (recvspace < minspace) {
1241                 ICL_WARN("kern.icl.recvspace too low; must be at least %zd",
1242                     minspace);
1243                 recvspace = minspace;
1244         }
1245
1246         error = soreserve(ic->ic_socket, sendspace, recvspace);
1247         if (error != 0) {
1248                 ICL_WARN("soreserve failed with error %d", error);
1249                 icl_soft_conn_close(ic);
1250                 return (error);
1251         }
1252         ic->ic_socket->so_snd.sb_flags |= SB_AUTOSIZE;
1253         ic->ic_socket->so_rcv.sb_flags |= SB_AUTOSIZE;
1254
1255         /*
1256          * Disable Nagle.
1257          */
1258         bzero(&opt, sizeof(opt));
1259         opt.sopt_dir = SOPT_SET;
1260         opt.sopt_level = IPPROTO_TCP;
1261         opt.sopt_name = TCP_NODELAY;
1262         opt.sopt_val = &one;
1263         opt.sopt_valsize = sizeof(one);
1264         error = sosetopt(ic->ic_socket, &opt);
1265         if (error != 0) {
1266                 ICL_WARN("disabling TCP_NODELAY failed with error %d", error);
1267                 icl_soft_conn_close(ic);
1268                 return (error);
1269         }
1270
1271         /*
1272          * Register socket upcall, to get notified about incoming PDUs
1273          * and free space to send outgoing ones.
1274          */
1275         SOCKBUF_LOCK(&ic->ic_socket->so_snd);
1276         soupcall_set(ic->ic_socket, SO_SND, icl_soupcall_send, ic);
1277         SOCKBUF_UNLOCK(&ic->ic_socket->so_snd);
1278         SOCKBUF_LOCK(&ic->ic_socket->so_rcv);
1279         soupcall_set(ic->ic_socket, SO_RCV, icl_soupcall_receive, ic);
1280         SOCKBUF_UNLOCK(&ic->ic_socket->so_rcv);
1281
1282         /*
1283          * Start threads.
1284          */
1285         ICL_CONN_LOCK(ic);
1286         ic->ic_send_running = ic->ic_receive_running = true;
1287         ICL_CONN_UNLOCK(ic);
1288         error = kthread_add(icl_send_thread, ic, NULL, NULL, 0, 0, "%stx",
1289             ic->ic_name);
1290         if (error != 0) {
1291                 ICL_WARN("kthread_add(9) failed with error %d", error);
1292                 ICL_CONN_LOCK(ic);
1293                 ic->ic_send_running = ic->ic_receive_running = false;
1294                 cv_signal(&ic->ic_send_cv);
1295                 ICL_CONN_UNLOCK(ic);
1296                 icl_soft_conn_close(ic);
1297                 return (error);
1298         }
1299         error = kthread_add(icl_receive_thread, ic, NULL, NULL, 0, 0, "%srx",
1300             ic->ic_name);
1301         if (error != 0) {
1302                 ICL_WARN("kthread_add(9) failed with error %d", error);
1303                 ICL_CONN_LOCK(ic);
1304                 ic->ic_receive_running = false;
1305                 cv_signal(&ic->ic_send_cv);
1306                 ICL_CONN_UNLOCK(ic);
1307                 icl_soft_conn_close(ic);
1308                 return (error);
1309         }
1310
1311         return (0);
1312 }
1313
1314 int
1315 icl_soft_conn_handoff(struct icl_conn *ic, int fd)
1316 {
1317         struct file *fp;
1318         struct socket *so;
1319         cap_rights_t rights;
1320         int error;
1321
1322         ICL_CONN_LOCK_ASSERT_NOT(ic);
1323
1324         /*
1325          * Steal the socket from userland.
1326          */
1327         error = fget(curthread, fd,
1328             cap_rights_init(&rights, CAP_SOCK_CLIENT), &fp);
1329         if (error != 0)
1330                 return (error);
1331         if (fp->f_type != DTYPE_SOCKET) {
1332                 fdrop(fp, curthread);
1333                 return (EINVAL);
1334         }
1335         so = fp->f_data;
1336         if (so->so_type != SOCK_STREAM) {
1337                 fdrop(fp, curthread);
1338                 return (EINVAL);
1339         }
1340
1341         ICL_CONN_LOCK(ic);
1342
1343         if (ic->ic_socket != NULL) {
1344                 ICL_CONN_UNLOCK(ic);
1345                 fdrop(fp, curthread);
1346                 return (EBUSY);
1347         }
1348
1349         ic->ic_socket = fp->f_data;
1350         fp->f_ops = &badfileops;
1351         fp->f_data = NULL;
1352         fdrop(fp, curthread);
1353         ICL_CONN_UNLOCK(ic);
1354
1355         error = icl_conn_start(ic);
1356
1357         return (error);
1358 }
1359
1360 void
1361 icl_soft_conn_close(struct icl_conn *ic)
1362 {
1363         struct icl_pdu *pdu;
1364         struct socket *so;
1365
1366         ICL_CONN_LOCK(ic);
1367
1368         /*
1369          * Wake up the threads, so they can properly terminate.
1370          */
1371         ic->ic_disconnecting = true;
1372         while (ic->ic_receive_running || ic->ic_send_running) {
1373                 cv_signal(&ic->ic_receive_cv);
1374                 cv_signal(&ic->ic_send_cv);
1375                 cv_wait(&ic->ic_send_cv, ic->ic_lock);
1376         }
1377
1378         /* Some other thread could close the connection same time. */
1379         so = ic->ic_socket;
1380         if (so == NULL) {
1381                 ICL_CONN_UNLOCK(ic);
1382                 return;
1383         }
1384         ic->ic_socket = NULL;
1385
1386         /*
1387          * Deregister socket upcalls.
1388          */
1389         ICL_CONN_UNLOCK(ic);
1390         SOCKBUF_LOCK(&so->so_snd);
1391         if (so->so_snd.sb_upcall != NULL)
1392                 soupcall_clear(so, SO_SND);
1393         SOCKBUF_UNLOCK(&so->so_snd);
1394         SOCKBUF_LOCK(&so->so_rcv);
1395         if (so->so_rcv.sb_upcall != NULL)
1396                 soupcall_clear(so, SO_RCV);
1397         SOCKBUF_UNLOCK(&so->so_rcv);
1398         soclose(so);
1399         ICL_CONN_LOCK(ic);
1400
1401         if (ic->ic_receive_pdu != NULL) {
1402                 //ICL_DEBUG("freeing partially received PDU");
1403                 icl_pdu_free(ic->ic_receive_pdu);
1404                 ic->ic_receive_pdu = NULL;
1405         }
1406
1407         /*
1408          * Remove any outstanding PDUs from the send queue.
1409          */
1410         while (!STAILQ_EMPTY(&ic->ic_to_send)) {
1411                 pdu = STAILQ_FIRST(&ic->ic_to_send);
1412                 STAILQ_REMOVE_HEAD(&ic->ic_to_send, ip_next);
1413                 icl_pdu_free(pdu);
1414         }
1415
1416         KASSERT(STAILQ_EMPTY(&ic->ic_to_send),
1417             ("destroying session with non-empty send queue"));
1418 #ifdef DIAGNOSTIC
1419         KASSERT(ic->ic_outstanding_pdus == 0,
1420             ("destroying session with %d outstanding PDUs",
1421              ic->ic_outstanding_pdus));
1422 #endif
1423         ICL_CONN_UNLOCK(ic);
1424 }
1425
1426 int
1427 icl_soft_conn_task_setup(struct icl_conn *ic, struct ccb_scsiio *csio,
1428     uint32_t *task_tagp, void **prvp)
1429 {
1430
1431         return (0);
1432 }
1433
1434 void
1435 icl_soft_conn_task_done(struct icl_conn *ic, void *prv)
1436 {
1437 }
1438
1439 int
1440 icl_soft_conn_transfer_setup(struct icl_conn *ic, union ctl_io *io,
1441     uint32_t *transfer_tag, void **prvp)
1442 {
1443
1444         return (0);
1445 }
1446
1447 void
1448 icl_soft_conn_transfer_done(struct icl_conn *ic, void *prv)
1449 {
1450 }
1451
1452 static int
1453 icl_soft_limits(size_t *limitp)
1454 {
1455
1456         *limitp = 128 * 1024;
1457
1458         return (0);
1459 }
1460
1461 #ifdef ICL_KERNEL_PROXY
1462 int
1463 icl_conn_handoff_sock(struct icl_conn *ic, struct socket *so)
1464 {
1465         int error;
1466
1467         ICL_CONN_LOCK_ASSERT_NOT(ic);
1468
1469         if (so->so_type != SOCK_STREAM)
1470                 return (EINVAL);
1471
1472         ICL_CONN_LOCK(ic);
1473         if (ic->ic_socket != NULL) {
1474                 ICL_CONN_UNLOCK(ic);
1475                 return (EBUSY);
1476         }
1477         ic->ic_socket = so;
1478         ICL_CONN_UNLOCK(ic);
1479
1480         error = icl_conn_start(ic);
1481
1482         return (error);
1483 }
1484 #endif /* ICL_KERNEL_PROXY */
1485
1486 static int
1487 icl_soft_load(void)
1488 {
1489         int error;
1490
1491         icl_pdu_zone = uma_zcreate("icl_pdu",
1492             sizeof(struct icl_pdu), NULL, NULL, NULL, NULL,
1493             UMA_ALIGN_PTR, 0);
1494         refcount_init(&icl_ncons, 0);
1495
1496         /*
1497          * The reason we call this "none" is that to the user,
1498          * it's known as "offload driver"; "offload driver: soft"
1499          * doesn't make much sense.
1500          */
1501         error = icl_register("none", 0, icl_soft_limits, icl_soft_new_conn);
1502         KASSERT(error == 0, ("failed to register"));
1503
1504         return (error);
1505 }
1506
1507 static int
1508 icl_soft_unload(void)
1509 {
1510
1511         if (icl_ncons != 0)
1512                 return (EBUSY);
1513
1514         icl_unregister("none");
1515
1516         uma_zdestroy(icl_pdu_zone);
1517
1518         return (0);
1519 }
1520
1521 static int
1522 icl_soft_modevent(module_t mod, int what, void *arg)
1523 {
1524
1525         switch (what) {
1526         case MOD_LOAD:
1527                 return (icl_soft_load());
1528         case MOD_UNLOAD:
1529                 return (icl_soft_unload());
1530         default:
1531                 return (EINVAL);
1532         }
1533 }
1534
1535 moduledata_t icl_soft_data = {
1536         "icl_soft",
1537         icl_soft_modevent,
1538         0
1539 };
1540
1541 DECLARE_MODULE(icl_soft, icl_soft_data, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
1542 MODULE_DEPEND(icl_soft, icl, 1, 1, 1);
1543 MODULE_VERSION(icl_soft, 1);