block/iscsi.c

   1 /*
   2  * QEMU Block driver for iSCSI images
   3  *
   4  * Copyright (c) 2010-2011 Ronnie Sahlberg <ronniesahlberg@gmail.com>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "config-host.h"
  26
  27 #include <poll.h>
  28 #include <arpa/inet.h>
  29 #include "qemu-common.h"
  30 #include "qemu/config-file.h"
  31 #include "qemu/error-report.h"
  32 #include "block/block_int.h"
  33 #include "trace.h"
  34 #include "block/scsi.h"
  35
  36 #include <iscsi/iscsi.h>
  37 #include <iscsi/scsi-lowlevel.h>
  38
  39 #ifdef __linux__
  40 #include <scsi/sg.h>
  41 #include <block/scsi.h>
  42 #endif
  43
  44 typedef struct IscsiLun {
  45     struct iscsi_context *iscsi;
  46     int lun;
  47     enum scsi_inquiry_peripheral_device_type type;
  48     int block_size;
  49     uint64_t num_blocks;
  50     int events;
  51     QEMUTimer *nop_timer;
  52 } IscsiLun;
  53
  54 typedef struct IscsiAIOCB {
  55     BlockDriverAIOCB common;
  56     QEMUIOVector *qiov;
  57     QEMUBH *bh;
  58     IscsiLun *iscsilun;
  59     struct scsi_task *task;
  60     uint8_t *buf;
  61     int status;
  62     int canceled;
  63     int retries;
  64     size_t read_size;
  65     size_t read_offset;
  66     int64_t sector_num;
  67     int nb_sectors;
  68 #ifdef __linux__
  69     sg_io_hdr_t *ioh;
  70 #endif
  71 } IscsiAIOCB;
  72
  73 #define NOP_INTERVAL 5000
  74 #define MAX_NOP_FAILURES 3
  75 #define ISCSI_CMD_RETRIES 5
  76
  77 static void
  78 iscsi_bh_cb(void *p)
  79 {
  80     IscsiAIOCB *acb = p;
  81
  82     qemu_bh_delete(acb->bh);
  83
  84     g_free(acb->buf);
  85     acb->buf = NULL;
  86
  87     if (acb->canceled == 0) {
  88         acb->common.cb(acb->common.opaque, acb->status);
  89     }
  90
  91     if (acb->task != NULL) {
  92         scsi_free_scsi_task(acb->task);
  93         acb->task = NULL;
  94     }
  95
  96     qemu_aio_release(acb);
  97 }
  98
  99 static void
 100 iscsi_schedule_bh(IscsiAIOCB *acb)
 101 {
 102     if (acb->bh) {
 103         return;
 104     }
 105     acb->bh = qemu_bh_new(iscsi_bh_cb, acb);
 106     qemu_bh_schedule(acb->bh);
 107 }
 108
 109
 110 static void
 111 iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
 112                     void *private_data)
 113 {
 114     IscsiAIOCB *acb = private_data;
 115
 116     acb->status = -ECANCELED;
 117     iscsi_schedule_bh(acb);
 118 }
 119
 120 static void
 121 iscsi_aio_cancel(BlockDriverAIOCB *blockacb)
 122 {
 123     IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
 124     IscsiLun *iscsilun = acb->iscsilun;
 125
 126     if (acb->status != -EINPROGRESS) {
 127         return;
 128     }
 129
 130     acb->canceled = 1;
 131
 132     /* send a task mgmt call to the target to cancel the task on the target */
 133     iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
 134                                      iscsi_abort_task_cb, acb);
 135
 136     while (acb->status == -EINPROGRESS) {
 137         qemu_aio_wait();
 138     }
 139 }
 140
 141 static const AIOCBInfo iscsi_aiocb_info = {
 142     .aiocb_size         = sizeof(IscsiAIOCB),
 143     .cancel             = iscsi_aio_cancel,
 144 };
 145
 146
 147 static void iscsi_process_read(void *arg);
 148 static void iscsi_process_write(void *arg);
 149
 150 static int iscsi_process_flush(void *arg)
 151 {
 152     IscsiLun *iscsilun = arg;
 153
 154     return iscsi_queue_length(iscsilun->iscsi) > 0;
 155 }
 156
 157 static void
 158 iscsi_set_events(IscsiLun *iscsilun)
 159 {
 160     struct iscsi_context *iscsi = iscsilun->iscsi;
 161     int ev;
 162
 163     /* We always register a read handler.  */
 164     ev = POLLIN;
 165     ev |= iscsi_which_events(iscsi);
 166     if (ev != iscsilun->events) {
 167         qemu_aio_set_fd_handler(iscsi_get_fd(iscsi),
 168                       iscsi_process_read,
 169                       (ev & POLLOUT) ? iscsi_process_write : NULL,
 170                       iscsi_process_flush,
 171                       iscsilun);
 172
 173     }
 174
 175     iscsilun->events = ev;
 176 }
 177
 178 static void
 179 iscsi_process_read(void *arg)
 180 {
 181     IscsiLun *iscsilun = arg;
 182     struct iscsi_context *iscsi = iscsilun->iscsi;
 183
 184     iscsi_service(iscsi, POLLIN);
 185     iscsi_set_events(iscsilun);
 186 }
 187
 188 static void
 189 iscsi_process_write(void *arg)
 190 {
 191     IscsiLun *iscsilun = arg;
 192     struct iscsi_context *iscsi = iscsilun->iscsi;
 193
 194     iscsi_service(iscsi, POLLOUT);
 195     iscsi_set_events(iscsilun);
 196 }
 197
 198 static int
 199 iscsi_aio_writev_acb(IscsiAIOCB *acb);
 200
 201 static void
 202 iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status,
 203                      void *command_data, void *opaque)
 204 {
 205     IscsiAIOCB *acb = opaque;
 206
 207     trace_iscsi_aio_write16_cb(iscsi, status, acb, acb->canceled);
 208
 209     g_free(acb->buf);
 210     acb->buf = NULL;
 211
 212     if (acb->canceled != 0) {
 213         return;
 214     }
 215
 216     acb->status = 0;
 217     if (status != 0) {
 218         if (status == SCSI_STATUS_CHECK_CONDITION
 219             && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION
 220             && acb->retries-- > 0) {
 221             if (acb->task != NULL) {
 222                 scsi_free_scsi_task(acb->task);
 223                 acb->task = NULL;
 224             }
 225             if (iscsi_aio_writev_acb(acb) == 0) {
 226                 iscsi_set_events(acb->iscsilun);
 227                 return;
 228             }
 229         }
 230         error_report("Failed to write16 data to iSCSI lun. %s",
 231                      iscsi_get_error(iscsi));
 232         acb->status = -EIO;
 233     }
 234
 235     iscsi_schedule_bh(acb);
 236 }
 237
 238 static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
 239 {
 240     return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
 241 }
 242
 243 static int
 244 iscsi_aio_writev_acb(IscsiAIOCB *acb)
 245 {
 246     struct iscsi_context *iscsi = acb->iscsilun->iscsi;
 247     size_t size;
 248     uint32_t num_sectors;
 249     uint64_t lba;
 250 #if !defined(LIBISCSI_FEATURE_IOVECTOR)
 251     struct iscsi_data data;
 252 #endif
 253     int ret;
 254
 255     acb->canceled   = 0;
 256     acb->bh         = NULL;
 257     acb->status     = -EINPROGRESS;
 258     acb->buf        = NULL;
 259
 260     /* this will allow us to get rid of 'buf' completely */
 261     size = acb->nb_sectors * BDRV_SECTOR_SIZE;
 262
 263 #if !defined(LIBISCSI_FEATURE_IOVECTOR)
 264     data.size = MIN(size, acb->qiov->size);
 265
 266     /* if the iovec only contains one buffer we can pass it directly */
 267     if (acb->qiov->niov == 1) {
 268         data.data = acb->qiov->iov[0].iov_base;
 269     } else {
 270         acb->buf = g_malloc(data.size);
 271         qemu_iovec_to_buf(acb->qiov, 0, acb->buf, data.size);
 272         data.data = acb->buf;
 273     }
 274 #endif
 275
 276     acb->task = malloc(sizeof(struct scsi_task));
 277     if (acb->task == NULL) {
 278         error_report("iSCSI: Failed to allocate task for scsi WRITE16 "
 279                      "command. %s", iscsi_get_error(iscsi));
 280         return -1;
 281     }
 282     memset(acb->task, 0, sizeof(struct scsi_task));
 283
 284     acb->task->xfer_dir = SCSI_XFER_WRITE;
 285     acb->task->cdb_size = 16;
 286     acb->task->cdb[0] = 0x8a;
 287     lba = sector_qemu2lun(acb->sector_num, acb->iscsilun);
 288     *(uint32_t *)&acb->task->cdb[2]  = htonl(lba >> 32);
 289     *(uint32_t *)&acb->task->cdb[6]  = htonl(lba & 0xffffffff);
 290     num_sectors = size / acb->iscsilun->block_size;
 291     *(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors);
 292     acb->task->expxferlen = size;
 293
 294 #if defined(LIBISCSI_FEATURE_IOVECTOR)
 295     ret = iscsi_scsi_command_async(iscsi, acb->iscsilun->lun, acb->task,
 296                                    iscsi_aio_write16_cb,
 297                                    NULL,
 298                                    acb);
 299 #else
 300     ret = iscsi_scsi_command_async(iscsi, acb->iscsilun->lun, acb->task,
 301                                    iscsi_aio_write16_cb,
 302                                    &data,
 303                                    acb);
 304 #endif
 305     if (ret != 0) {
 306         g_free(acb->buf);
 307         return -1;
 308     }
 309
 310 #if defined(LIBISCSI_FEATURE_IOVECTOR)
 311     scsi_task_set_iov_out(acb->task, (struct scsi_iovec*) acb->qiov->iov, acb->qiov->niov);
 312 #endif
 313
 314     return 0;
 315 }
 316
 317 static BlockDriverAIOCB *
 318 iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num,
 319                  QEMUIOVector *qiov, int nb_sectors,
 320                  BlockDriverCompletionFunc *cb,
 321                  void *opaque)
 322 {
 323     IscsiLun *iscsilun = bs->opaque;
 324     IscsiAIOCB *acb;
 325
 326     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 327     trace_iscsi_aio_writev(iscsilun->iscsi, sector_num, nb_sectors, opaque, acb);
 328
 329     acb->iscsilun    = iscsilun;
 330     acb->qiov        = qiov;
 331     acb->nb_sectors  = nb_sectors;
 332     acb->sector_num  = sector_num;
 333     acb->retries     = ISCSI_CMD_RETRIES;
 334
 335     if (iscsi_aio_writev_acb(acb) != 0) {
 336         if (acb->task) {
 337             scsi_free_scsi_task(acb->task);
 338         }
 339         qemu_aio_release(acb);
 340         return NULL;
 341     }
 342
 343     iscsi_set_events(iscsilun);
 344     return &acb->common;
 345 }
 346
 347 static int
 348 iscsi_aio_readv_acb(IscsiAIOCB *acb);
 349
 350 static void
 351 iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status,
 352                     void *command_data, void *opaque)
 353 {
 354     IscsiAIOCB *acb = opaque;
 355
 356     trace_iscsi_aio_read16_cb(iscsi, status, acb, acb->canceled);
 357
 358     if (acb->canceled != 0) {
 359         return;
 360     }
 361
 362     acb->status = 0;
 363     if (status != 0) {
 364         if (status == SCSI_STATUS_CHECK_CONDITION
 365             && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION
 366             && acb->retries-- > 0) {
 367             if (acb->task != NULL) {
 368                 scsi_free_scsi_task(acb->task);
 369                 acb->task = NULL;
 370             }
 371             if (iscsi_aio_readv_acb(acb) == 0) {
 372                 iscsi_set_events(acb->iscsilun);
 373                 return;
 374             }
 375         }
 376         error_report("Failed to read16 data from iSCSI lun. %s",
 377                      iscsi_get_error(iscsi));
 378         acb->status = -EIO;
 379     }
 380
 381     iscsi_schedule_bh(acb);
 382 }
 383
 384 static int
 385 iscsi_aio_readv_acb(IscsiAIOCB *acb)
 386 {
 387     struct iscsi_context *iscsi = acb->iscsilun->iscsi;
 388     uint64_t lba;
 389     uint32_t num_sectors;
 390     int ret;
 391 #if !defined(LIBISCSI_FEATURE_IOVECTOR)
 392     int i;
 393 #endif
 394
 395     acb->canceled    = 0;
 396     acb->bh          = NULL;
 397     acb->status      = -EINPROGRESS;
 398     acb->buf         = NULL;
 399
 400     /* If LUN blocksize is bigger than BDRV_BLOCK_SIZE a read from QEMU
 401      * may be misaligned to the LUN, so we may need to read some extra
 402      * data.
 403      */
 404     acb->read_offset = 0;
 405     if (acb->iscsilun->block_size > BDRV_SECTOR_SIZE) {
 406         uint64_t bdrv_offset = BDRV_SECTOR_SIZE * acb->sector_num;
 407
 408         acb->read_offset  = bdrv_offset % acb->iscsilun->block_size;
 409     }
 410
 411     num_sectors  = (acb->read_size + acb->iscsilun->block_size
 412                     + acb->read_offset - 1)
 413                     / acb->iscsilun->block_size;
 414
 415     acb->task = malloc(sizeof(struct scsi_task));
 416     if (acb->task == NULL) {
 417         error_report("iSCSI: Failed to allocate task for scsi READ16 "
 418                      "command. %s", iscsi_get_error(iscsi));
 419         return -1;
 420     }
 421     memset(acb->task, 0, sizeof(struct scsi_task));
 422
 423     acb->task->xfer_dir = SCSI_XFER_READ;
 424     lba = sector_qemu2lun(acb->sector_num, acb->iscsilun);
 425     acb->task->expxferlen = acb->read_size;
 426
 427     switch (acb->iscsilun->type) {
 428     case TYPE_DISK:
 429         acb->task->cdb_size = 16;
 430         acb->task->cdb[0]  = 0x88;
 431         *(uint32_t *)&acb->task->cdb[2]  = htonl(lba >> 32);
 432         *(uint32_t *)&acb->task->cdb[6]  = htonl(lba & 0xffffffff);
 433         *(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors);
 434         break;
 435     default:
 436         acb->task->cdb_size = 10;
 437         acb->task->cdb[0]  = 0x28;
 438         *(uint32_t *)&acb->task->cdb[2] = htonl(lba);
 439         *(uint16_t *)&acb->task->cdb[7] = htons(num_sectors);
 440         break;
 441     }
 442
 443     ret = iscsi_scsi_command_async(iscsi, acb->iscsilun->lun, acb->task,
 444                                    iscsi_aio_read16_cb,
 445                                    NULL,
 446                                    acb);
 447     if (ret != 0) {
 448         return -1;
 449     }
 450
 451 #if defined(LIBISCSI_FEATURE_IOVECTOR)
 452     scsi_task_set_iov_in(acb->task, (struct scsi_iovec*) acb->qiov->iov, acb->qiov->niov);
 453 #else
 454     for (i = 0; i < acb->qiov->niov; i++) {
 455         scsi_task_add_data_in_buffer(acb->task,
 456                 acb->qiov->iov[i].iov_len,
 457                 acb->qiov->iov[i].iov_base);
 458     }
 459 #endif
 460     return 0;
 461 }
 462
 463 static BlockDriverAIOCB *
 464 iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num,
 465                 QEMUIOVector *qiov, int nb_sectors,
 466                 BlockDriverCompletionFunc *cb,
 467                 void *opaque)
 468 {
 469     IscsiLun *iscsilun = bs->opaque;
 470     IscsiAIOCB *acb;
 471
 472     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 473     trace_iscsi_aio_readv(iscsilun->iscsi, sector_num, nb_sectors, opaque, acb);
 474
 475     acb->nb_sectors  = nb_sectors;
 476     acb->sector_num  = sector_num;
 477     acb->iscsilun    = iscsilun;
 478     acb->qiov        = qiov;
 479     acb->read_size   = BDRV_SECTOR_SIZE * (size_t)acb->nb_sectors;
 480     acb->retries     = ISCSI_CMD_RETRIES;
 481
 482     if (iscsi_aio_readv_acb(acb) != 0) {
 483         if (acb->task) {
 484             scsi_free_scsi_task(acb->task);
 485         }
 486         qemu_aio_release(acb);
 487         return NULL;
 488     }
 489
 490     iscsi_set_events(iscsilun);
 491     return &acb->common;
 492 }
 493
 494 static int
 495 iscsi_aio_flush_acb(IscsiAIOCB *acb);
 496
 497 static void
 498 iscsi_synccache10_cb(struct iscsi_context *iscsi, int status,
 499                      void *command_data, void *opaque)
 500 {
 501     IscsiAIOCB *acb = opaque;
 502
 503     if (acb->canceled != 0) {
 504         return;
 505     }
 506
 507     acb->status = 0;
 508     if (status != 0) {
 509         if (status == SCSI_STATUS_CHECK_CONDITION
 510             && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION
 511             && acb->retries-- > 0) {
 512             if (acb->task != NULL) {
 513                 scsi_free_scsi_task(acb->task);
 514                 acb->task = NULL;
 515             }
 516             if (iscsi_aio_flush_acb(acb) == 0) {
 517                 iscsi_set_events(acb->iscsilun);
 518                 return;
 519             }
 520         }
 521         error_report("Failed to sync10 data on iSCSI lun. %s",
 522                      iscsi_get_error(iscsi));
 523         acb->status = -EIO;
 524     }
 525
 526     iscsi_schedule_bh(acb);
 527 }
 528
 529 static int
 530 iscsi_aio_flush_acb(IscsiAIOCB *acb)
 531 {
 532     struct iscsi_context *iscsi = acb->iscsilun->iscsi;
 533
 534     acb->canceled   = 0;
 535     acb->bh         = NULL;
 536     acb->status     = -EINPROGRESS;
 537     acb->buf        = NULL;
 538
 539     acb->task = iscsi_synchronizecache10_task(iscsi, acb->iscsilun->lun,
 540                                          0, 0, 0, 0,
 541                                          iscsi_synccache10_cb,
 542                                          acb);
 543     if (acb->task == NULL) {
 544         error_report("iSCSI: Failed to send synchronizecache10 command. %s",
 545                      iscsi_get_error(iscsi));
 546         return -1;
 547     }
 548
 549     return 0;
 550 }
 551
 552 static BlockDriverAIOCB *
 553 iscsi_aio_flush(BlockDriverState *bs,
 554                 BlockDriverCompletionFunc *cb, void *opaque)
 555 {
 556     IscsiLun *iscsilun = bs->opaque;
 557
 558     IscsiAIOCB *acb;
 559
 560     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 561
 562     acb->iscsilun    = iscsilun;
 563     acb->retries     = ISCSI_CMD_RETRIES;
 564
 565     if (iscsi_aio_flush_acb(acb) != 0) {
 566         qemu_aio_release(acb);
 567         return NULL;
 568     }
 569
 570     iscsi_set_events(iscsilun);
 571
 572     return &acb->common;
 573 }
 574
 575 static int iscsi_aio_discard_acb(IscsiAIOCB *acb);
 576
 577 static void
 578 iscsi_unmap_cb(struct iscsi_context *iscsi, int status,
 579                      void *command_data, void *opaque)
 580 {
 581     IscsiAIOCB *acb = opaque;
 582
 583     if (acb->canceled != 0) {
 584         return;
 585     }
 586
 587     acb->status = 0;
 588     if (status != 0) {
 589         if (status == SCSI_STATUS_CHECK_CONDITION
 590             && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION
 591             && acb->retries-- > 0) {
 592             if (acb->task != NULL) {
 593                 scsi_free_scsi_task(acb->task);
 594                 acb->task = NULL;
 595             }
 596             if (iscsi_aio_discard_acb(acb) == 0) {
 597                 iscsi_set_events(acb->iscsilun);
 598                 return;
 599             }
 600         }
 601         error_report("Failed to unmap data on iSCSI lun. %s",
 602                      iscsi_get_error(iscsi));
 603         acb->status = -EIO;
 604     }
 605
 606     iscsi_schedule_bh(acb);
 607 }
 608
 609 static int iscsi_aio_discard_acb(IscsiAIOCB *acb) {
 610     struct iscsi_context *iscsi = acb->iscsilun->iscsi;
 611     struct unmap_list list[1];
 612
 613     acb->canceled   = 0;
 614     acb->bh         = NULL;
 615     acb->status     = -EINPROGRESS;
 616     acb->buf        = NULL;
 617
 618     list[0].lba = sector_qemu2lun(acb->sector_num, acb->iscsilun);
 619     list[0].num = acb->nb_sectors * BDRV_SECTOR_SIZE / acb->iscsilun->block_size;
 620
 621     acb->task = iscsi_unmap_task(iscsi, acb->iscsilun->lun,
 622                                  0, 0, &list[0], 1,
 623                                  iscsi_unmap_cb,
 624                                  acb);
 625     if (acb->task == NULL) {
 626         error_report("iSCSI: Failed to send unmap command. %s",
 627                      iscsi_get_error(iscsi));
 628         return -1;
 629     }
 630
 631     return 0;
 632 }
 633
 634 static BlockDriverAIOCB *
 635 iscsi_aio_discard(BlockDriverState *bs,
 636                   int64_t sector_num, int nb_sectors,
 637                   BlockDriverCompletionFunc *cb, void *opaque)
 638 {
 639     IscsiLun *iscsilun = bs->opaque;
 640     IscsiAIOCB *acb;
 641
 642     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 643
 644     acb->iscsilun    = iscsilun;
 645     acb->nb_sectors  = nb_sectors;
 646     acb->sector_num  = sector_num;
 647     acb->retries     = ISCSI_CMD_RETRIES;
 648
 649     if (iscsi_aio_discard_acb(acb) != 0) {
 650         if (acb->task) {
 651             scsi_free_scsi_task(acb->task);
 652         }
 653         qemu_aio_release(acb);
 654         return NULL;
 655     }
 656
 657     iscsi_set_events(iscsilun);
 658
 659     return &acb->common;
 660 }
 661
 662 #ifdef __linux__
 663 static void
 664 iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
 665                      void *command_data, void *opaque)
 666 {
 667     IscsiAIOCB *acb = opaque;
 668
 669     if (acb->canceled != 0) {
 670         return;
 671     }
 672
 673     acb->status = 0;
 674     if (status < 0) {
 675         error_report("Failed to ioctl(SG_IO) to iSCSI lun. %s",
 676                      iscsi_get_error(iscsi));
 677         acb->status = -EIO;
 678     }
 679
 680     acb->ioh->driver_status = 0;
 681     acb->ioh->host_status   = 0;
 682     acb->ioh->resid         = 0;
 683
 684 #define SG_ERR_DRIVER_SENSE    0x08
 685
 686     if (status == SCSI_STATUS_CHECK_CONDITION && acb->task->datain.size >= 2) {
 687         int ss;
 688
 689         acb->ioh->driver_status |= SG_ERR_DRIVER_SENSE;
 690
 691         acb->ioh->sb_len_wr = acb->task->datain.size - 2;
 692         ss = (acb->ioh->mx_sb_len >= acb->ioh->sb_len_wr) ?
 693              acb->ioh->mx_sb_len : acb->ioh->sb_len_wr;
 694         memcpy(acb->ioh->sbp, &acb->task->datain.data[2], ss);
 695     }
 696
 697     iscsi_schedule_bh(acb);
 698 }
 699
 700 static BlockDriverAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
 701         unsigned long int req, void *buf,
 702         BlockDriverCompletionFunc *cb, void *opaque)
 703 {
 704     IscsiLun *iscsilun = bs->opaque;
 705     struct iscsi_context *iscsi = iscsilun->iscsi;
 706     struct iscsi_data data;
 707     IscsiAIOCB *acb;
 708
 709     assert(req == SG_IO);
 710
 711     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 712
 713     acb->iscsilun = iscsilun;
 714     acb->canceled    = 0;
 715     acb->bh          = NULL;
 716     acb->status      = -EINPROGRESS;
 717     acb->buf         = NULL;
 718     acb->ioh         = buf;
 719
 720     acb->task = malloc(sizeof(struct scsi_task));
 721     if (acb->task == NULL) {
 722         error_report("iSCSI: Failed to allocate task for scsi command. %s",
 723                      iscsi_get_error(iscsi));
 724         qemu_aio_release(acb);
 725         return NULL;
 726     }
 727     memset(acb->task, 0, sizeof(struct scsi_task));
 728
 729     switch (acb->ioh->dxfer_direction) {
 730     case SG_DXFER_TO_DEV:
 731         acb->task->xfer_dir = SCSI_XFER_WRITE;
 732         break;
 733     case SG_DXFER_FROM_DEV:
 734         acb->task->xfer_dir = SCSI_XFER_READ;
 735         break;
 736     default:
 737         acb->task->xfer_dir = SCSI_XFER_NONE;
 738         break;
 739     }
 740
 741     acb->task->cdb_size = acb->ioh->cmd_len;
 742     memcpy(&acb->task->cdb[0], acb->ioh->cmdp, acb->ioh->cmd_len);
 743     acb->task->expxferlen = acb->ioh->dxfer_len;
 744
 745     if (acb->task->xfer_dir == SCSI_XFER_WRITE) {
 746         data.data = acb->ioh->dxferp;
 747         data.size = acb->ioh->dxfer_len;
 748     }
 749     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
 750                                  iscsi_aio_ioctl_cb,
 751                                  (acb->task->xfer_dir == SCSI_XFER_WRITE) ?
 752                                      &data : NULL,
 753                                  acb) != 0) {
 754         scsi_free_scsi_task(acb->task);
 755         qemu_aio_release(acb);
 756         return NULL;
 757     }
 758
 759     /* tell libiscsi to read straight into the buffer we got from ioctl */
 760     if (acb->task->xfer_dir == SCSI_XFER_READ) {
 761         scsi_task_add_data_in_buffer(acb->task,
 762                                      acb->ioh->dxfer_len,
 763                                      acb->ioh->dxferp);
 764     }
 765
 766     iscsi_set_events(iscsilun);
 767
 768     return &acb->common;
 769 }
 770
 771
 772 static void ioctl_cb(void *opaque, int status)
 773 {
 774     int *p_status = opaque;
 775     *p_status = status;
 776 }
 777
 778 static int iscsi_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
 779 {
 780     IscsiLun *iscsilun = bs->opaque;
 781     int status;
 782
 783     switch (req) {
 784     case SG_GET_VERSION_NUM:
 785         *(int *)buf = 30000;
 786         break;
 787     case SG_GET_SCSI_ID:
 788         ((struct sg_scsi_id *)buf)->scsi_type = iscsilun->type;
 789         break;
 790     case SG_IO:
 791         status = -EINPROGRESS;
 792         iscsi_aio_ioctl(bs, req, buf, ioctl_cb, &status);
 793
 794         while (status == -EINPROGRESS) {
 795             qemu_aio_wait();
 796         }
 797
 798         return 0;
 799     default:
 800         return -1;
 801     }
 802     return 0;
 803 }
 804 #endif
 805
 806 static int64_t
 807 iscsi_getlength(BlockDriverState *bs)
 808 {
 809     IscsiLun *iscsilun = bs->opaque;
 810     int64_t len;
 811
 812     len  = iscsilun->num_blocks;
 813     len *= iscsilun->block_size;
 814
 815     return len;
 816 }
 817
 818 static int parse_chap(struct iscsi_context *iscsi, const char *target)
 819 {
 820     QemuOptsList *list;
 821     QemuOpts *opts;
 822     const char *user = NULL;
 823     const char *password = NULL;
 824
 825     list = qemu_find_opts("iscsi");
 826     if (!list) {
 827         return 0;
 828     }
 829
 830     opts = qemu_opts_find(list, target);
 831     if (opts == NULL) {
 832         opts = QTAILQ_FIRST(&list->head);
 833         if (!opts) {
 834             return 0;
 835         }
 836     }
 837
 838     user = qemu_opt_get(opts, "user");
 839     if (!user) {
 840         return 0;
 841     }
 842
 843     password = qemu_opt_get(opts, "password");
 844     if (!password) {
 845         error_report("CHAP username specified but no password was given");
 846         return -1;
 847     }
 848
 849     if (iscsi_set_initiator_username_pwd(iscsi, user, password)) {
 850         error_report("Failed to set initiator username and password");
 851         return -1;
 852     }
 853
 854     return 0;
 855 }
 856
 857 static void parse_header_digest(struct iscsi_context *iscsi, const char *target)
 858 {
 859     QemuOptsList *list;
 860     QemuOpts *opts;
 861     const char *digest = NULL;
 862
 863     list = qemu_find_opts("iscsi");
 864     if (!list) {
 865         return;
 866     }
 867
 868     opts = qemu_opts_find(list, target);
 869     if (opts == NULL) {
 870         opts = QTAILQ_FIRST(&list->head);
 871         if (!opts) {
 872             return;
 873         }
 874     }
 875
 876     digest = qemu_opt_get(opts, "header-digest");
 877     if (!digest) {
 878         return;
 879     }
 880
 881     if (!strcmp(digest, "CRC32C")) {
 882         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C);
 883     } else if (!strcmp(digest, "NONE")) {
 884         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE);
 885     } else if (!strcmp(digest, "CRC32C-NONE")) {
 886         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C_NONE);
 887     } else if (!strcmp(digest, "NONE-CRC32C")) {
 888         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
 889     } else {
 890         error_report("Invalid header-digest setting : %s", digest);
 891     }
 892 }
 893
 894 static char *parse_initiator_name(const char *target)
 895 {
 896     QemuOptsList *list;
 897     QemuOpts *opts;
 898     const char *name = NULL;
 899     const char *iscsi_name = qemu_get_vm_name();
 900
 901     list = qemu_find_opts("iscsi");
 902     if (list) {
 903         opts = qemu_opts_find(list, target);
 904         if (!opts) {
 905             opts = QTAILQ_FIRST(&list->head);
 906         }
 907         if (opts) {
 908             name = qemu_opt_get(opts, "initiator-name");
 909         }
 910     }
 911
 912     if (name) {
 913         return g_strdup(name);
 914     } else {
 915         return g_strdup_printf("iqn.2008-11.org.linux-kvm%s%s",
 916                                iscsi_name ? ":" : "",
 917                                iscsi_name ? iscsi_name : "");
 918     }
 919 }
 920
 921 #if defined(LIBISCSI_FEATURE_NOP_COUNTER)
 922 static void iscsi_nop_timed_event(void *opaque)
 923 {
 924     IscsiLun *iscsilun = opaque;
 925
 926     if (iscsi_get_nops_in_flight(iscsilun->iscsi) > MAX_NOP_FAILURES) {
 927         error_report("iSCSI: NOP timeout. Reconnecting...");
 928         iscsi_reconnect(iscsilun->iscsi);
 929     }
 930
 931     if (iscsi_nop_out_async(iscsilun->iscsi, NULL, NULL, 0, NULL) != 0) {
 932         error_report("iSCSI: failed to sent NOP-Out. Disabling NOP messages.");
 933         return;
 934     }
 935
 936     qemu_mod_timer(iscsilun->nop_timer, qemu_get_clock_ms(rt_clock) + NOP_INTERVAL);
 937     iscsi_set_events(iscsilun);
 938 }
 939 #endif
 940
 941 static int iscsi_readcapacity_sync(IscsiLun *iscsilun)
 942 {
 943     struct scsi_task *task = NULL;
 944     struct scsi_readcapacity10 *rc10 = NULL;
 945     struct scsi_readcapacity16 *rc16 = NULL;
 946     int ret = 0;
 947     int retries = ISCSI_CMD_RETRIES;
 948
 949 try_again:
 950     switch (iscsilun->type) {
 951     case TYPE_DISK:
 952         task = iscsi_readcapacity16_sync(iscsilun->iscsi, iscsilun->lun);
 953         if (task == NULL || task->status != SCSI_STATUS_GOOD) {
 954             if (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
 955                     && task->sense.key == SCSI_SENSE_UNIT_ATTENTION
 956                     && retries-- > 0) {
 957                 scsi_free_scsi_task(task);
 958                 goto try_again;
 959             }
 960             error_report("iSCSI: failed to send readcapacity16 command.");
 961             ret = -EINVAL;
 962             goto out;
 963         }
 964         rc16 = scsi_datain_unmarshall(task);
 965         if (rc16 == NULL) {
 966             error_report("iSCSI: Failed to unmarshall readcapacity16 data.");
 967             ret = -EINVAL;
 968             goto out;
 969         }
 970         iscsilun->block_size = rc16->block_length;
 971         iscsilun->num_blocks = rc16->returned_lba + 1;
 972         break;
 973     case TYPE_ROM:
 974         task = iscsi_readcapacity10_sync(iscsilun->iscsi, iscsilun->lun, 0, 0);
 975         if (task == NULL || task->status != SCSI_STATUS_GOOD) {
 976             error_report("iSCSI: failed to send readcapacity10 command.");
 977             ret = -EINVAL;
 978             goto out;
 979         }
 980         rc10 = scsi_datain_unmarshall(task);
 981         if (rc10 == NULL) {
 982             error_report("iSCSI: Failed to unmarshall readcapacity10 data.");
 983             ret = -EINVAL;
 984             goto out;
 985         }
 986         iscsilun->block_size = rc10->block_size;
 987         if (rc10->lba == 0) {
 988             /* blank disk loaded */
 989             iscsilun->num_blocks = 0;
 990         } else {
 991             iscsilun->num_blocks = rc10->lba + 1;
 992         }
 993         break;
 994     default:
 995         break;
 996     }
 997
 998 out:
 999     if (task) {
1000         scsi_free_scsi_task(task);
1001     }
1002
1003     return ret;
1004 }
1005
1006 /*
1007  * We support iscsi url's on the form
1008  * iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>
1009  */
1010 static int iscsi_open(BlockDriverState *bs, const char *filename,
1011                       QDict *options, int flags)
1012 {
1013     IscsiLun *iscsilun = bs->opaque;
1014     struct iscsi_context *iscsi = NULL;
1015     struct iscsi_url *iscsi_url = NULL;
1016     struct scsi_task *task = NULL;
1017     struct scsi_inquiry_standard *inq = NULL;
1018     char *initiator_name = NULL;
1019     int ret;
1020
1021     if ((BDRV_SECTOR_SIZE % 512) != 0) {
1022         error_report("iSCSI: Invalid BDRV_SECTOR_SIZE. "
1023                      "BDRV_SECTOR_SIZE(%lld) is not a multiple "
1024                      "of 512", BDRV_SECTOR_SIZE);
1025         return -EINVAL;
1026     }
1027
1028     iscsi_url = iscsi_parse_full_url(iscsi, filename);
1029     if (iscsi_url == NULL) {
1030         error_report("Failed to parse URL : %s", filename);
1031         ret = -EINVAL;
1032         goto out;
1033     }
1034
1035     memset(iscsilun, 0, sizeof(IscsiLun));
1036
1037     initiator_name = parse_initiator_name(iscsi_url->target);
1038
1039     iscsi = iscsi_create_context(initiator_name);
1040     if (iscsi == NULL) {
1041         error_report("iSCSI: Failed to create iSCSI context.");
1042         ret = -ENOMEM;
1043         goto out;
1044     }
1045
1046     if (iscsi_set_targetname(iscsi, iscsi_url->target)) {
1047         error_report("iSCSI: Failed to set target name.");
1048         ret = -EINVAL;
1049         goto out;
1050     }
1051
1052     if (iscsi_url->user != NULL) {
1053         ret = iscsi_set_initiator_username_pwd(iscsi, iscsi_url->user,
1054                                               iscsi_url->passwd);
1055         if (ret != 0) {
1056             error_report("Failed to set initiator username and password");
1057             ret = -EINVAL;
1058             goto out;
1059         }
1060     }
1061
1062     /* check if we got CHAP username/password via the options */
1063     if (parse_chap(iscsi, iscsi_url->target) != 0) {
1064         error_report("iSCSI: Failed to set CHAP user/password");
1065         ret = -EINVAL;
1066         goto out;
1067     }
1068
1069     if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) != 0) {
1070         error_report("iSCSI: Failed to set session type to normal.");
1071         ret = -EINVAL;
1072         goto out;
1073     }
1074
1075     iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1076
1077     /* check if we got HEADER_DIGEST via the options */
1078     parse_header_digest(iscsi, iscsi_url->target);
1079
1080     if (iscsi_full_connect_sync(iscsi, iscsi_url->portal, iscsi_url->lun) != 0) {
1081         error_report("iSCSI: Failed to connect to LUN : %s",
1082             iscsi_get_error(iscsi));
1083         ret = -EINVAL;
1084         goto out;
1085     }
1086
1087     iscsilun->iscsi = iscsi;
1088     iscsilun->lun   = iscsi_url->lun;
1089
1090     task = iscsi_inquiry_sync(iscsi, iscsilun->lun, 0, 0, 36);
1091
1092     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1093         error_report("iSCSI: failed to send inquiry command.");
1094         ret = -EINVAL;
1095         goto out;
1096     }
1097
1098     inq = scsi_datain_unmarshall(task);
1099     if (inq == NULL) {
1100         error_report("iSCSI: Failed to unmarshall inquiry data.");
1101         ret = -EINVAL;
1102         goto out;
1103     }
1104
1105     iscsilun->type = inq->periperal_device_type;
1106
1107     if ((ret = iscsi_readcapacity_sync(iscsilun)) != 0) {
1108         goto out;
1109     }
1110     bs->total_sectors    = iscsilun->num_blocks *
1111                            iscsilun->block_size / BDRV_SECTOR_SIZE ;
1112
1113     /* Medium changer or tape. We dont have any emulation for this so this must
1114      * be sg ioctl compatible. We force it to be sg, otherwise qemu will try
1115      * to read from the device to guess the image format.
1116      */
1117     if (iscsilun->type == TYPE_MEDIUM_CHANGER ||
1118         iscsilun->type == TYPE_TAPE) {
1119         bs->sg = 1;
1120     }
1121
1122 #if defined(LIBISCSI_FEATURE_NOP_COUNTER)
1123     /* Set up a timer for sending out iSCSI NOPs */
1124     iscsilun->nop_timer = qemu_new_timer_ms(rt_clock, iscsi_nop_timed_event, iscsilun);
1125     qemu_mod_timer(iscsilun->nop_timer, qemu_get_clock_ms(rt_clock) + NOP_INTERVAL);
1126 #endif
1127
1128 out:
1129     if (initiator_name != NULL) {
1130         g_free(initiator_name);
1131     }
1132     if (iscsi_url != NULL) {
1133         iscsi_destroy_url(iscsi_url);
1134     }
1135     if (task != NULL) {
1136         scsi_free_scsi_task(task);
1137     }
1138
1139     if (ret) {
1140         if (iscsi != NULL) {
1141             iscsi_destroy_context(iscsi);
1142         }
1143         memset(iscsilun, 0, sizeof(IscsiLun));
1144     }
1145     return ret;
1146 }
1147
1148 static void iscsi_close(BlockDriverState *bs)
1149 {
1150     IscsiLun *iscsilun = bs->opaque;
1151     struct iscsi_context *iscsi = iscsilun->iscsi;
1152
1153     if (iscsilun->nop_timer) {
1154         qemu_del_timer(iscsilun->nop_timer);
1155         qemu_free_timer(iscsilun->nop_timer);
1156     }
1157     qemu_aio_set_fd_handler(iscsi_get_fd(iscsi), NULL, NULL, NULL, NULL);
1158     iscsi_destroy_context(iscsi);
1159     memset(iscsilun, 0, sizeof(IscsiLun));
1160 }
1161
1162 static int iscsi_truncate(BlockDriverState *bs, int64_t offset)
1163 {
1164     IscsiLun *iscsilun = bs->opaque;
1165     int ret = 0;
1166
1167     if (iscsilun->type != TYPE_DISK) {
1168         return -ENOTSUP;
1169     }
1170
1171     if ((ret = iscsi_readcapacity_sync(iscsilun)) != 0) {
1172         return ret;
1173     }
1174
1175     if (offset > iscsi_getlength(bs)) {
1176         return -EINVAL;
1177     }
1178
1179     return 0;
1180 }
1181
1182 static int iscsi_has_zero_init(BlockDriverState *bs)
1183 {
1184     return 0;
1185 }
1186
1187 static int iscsi_create(const char *filename, QEMUOptionParameter *options)
1188 {
1189     int ret = 0;
1190     int64_t total_size = 0;
1191     BlockDriverState bs;
1192     IscsiLun *iscsilun = NULL;
1193
1194     memset(&bs, 0, sizeof(BlockDriverState));
1195
1196     /* Read out options */
1197     while (options && options->name) {
1198         if (!strcmp(options->name, "size")) {
1199             total_size = options->value.n / BDRV_SECTOR_SIZE;
1200         }
1201         options++;
1202     }
1203
1204     bs.opaque = g_malloc0(sizeof(struct IscsiLun));
1205     iscsilun = bs.opaque;
1206
1207     ret = iscsi_open(&bs, filename, NULL, 0);
1208     if (ret != 0) {
1209         goto out;
1210     }
1211     if (iscsilun->nop_timer) {
1212         qemu_del_timer(iscsilun->nop_timer);
1213         qemu_free_timer(iscsilun->nop_timer);
1214     }
1215     if (iscsilun->type != TYPE_DISK) {
1216         ret = -ENODEV;
1217         goto out;
1218     }
1219     if (bs.total_sectors < total_size) {
1220         ret = -ENOSPC;
1221     }
1222
1223     ret = 0;
1224 out:
1225     if (iscsilun->iscsi != NULL) {
1226         iscsi_destroy_context(iscsilun->iscsi);
1227     }
1228     g_free(bs.opaque);
1229     return ret;
1230 }
1231
1232 static QEMUOptionParameter iscsi_create_options[] = {
1233     {
1234         .name = BLOCK_OPT_SIZE,
1235         .type = OPT_SIZE,
1236         .help = "Virtual disk size"
1237     },
1238     { NULL }
1239 };
1240
1241 static BlockDriver bdrv_iscsi = {
1242     .format_name     = "iscsi",
1243     .protocol_name   = "iscsi",
1244
1245     .instance_size   = sizeof(IscsiLun),
1246     .bdrv_file_open  = iscsi_open,
1247     .bdrv_close      = iscsi_close,
1248     .bdrv_create     = iscsi_create,
1249     .create_options  = iscsi_create_options,
1250
1251     .bdrv_getlength  = iscsi_getlength,
1252     .bdrv_truncate   = iscsi_truncate,
1253
1254     .bdrv_aio_readv  = iscsi_aio_readv,
1255     .bdrv_aio_writev = iscsi_aio_writev,
1256     .bdrv_aio_flush  = iscsi_aio_flush,
1257
1258     .bdrv_aio_discard = iscsi_aio_discard,
1259     .bdrv_has_zero_init = iscsi_has_zero_init,
1260
1261 #ifdef __linux__
1262     .bdrv_ioctl       = iscsi_ioctl,
1263     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
1264 #endif
1265 };
1266
1267 static QemuOptsList qemu_iscsi_opts = {
1268     .name = "iscsi",
1269     .head = QTAILQ_HEAD_INITIALIZER(qemu_iscsi_opts.head),
1270     .desc = {
1271         {
1272             .name = "user",
1273             .type = QEMU_OPT_STRING,
1274             .help = "username for CHAP authentication to target",
1275         },{
1276             .name = "password",
1277             .type = QEMU_OPT_STRING,
1278             .help = "password for CHAP authentication to target",
1279         },{
1280             .name = "header-digest",
1281             .type = QEMU_OPT_STRING,
1282             .help = "HeaderDigest setting. "
1283                     "{CRC32C|CRC32C-NONE|NONE-CRC32C|NONE}",
1284         },{
1285             .name = "initiator-name",
1286             .type = QEMU_OPT_STRING,
1287             .help = "Initiator iqn name to use when connecting",
1288         },
1289         { /* end of list */ }
1290     },
1291 };
1292
1293 static void iscsi_block_init(void)
1294 {
1295     bdrv_register(&bdrv_iscsi);
1296     qemu_add_opts(&qemu_iscsi_opts);
1297 }
1298
1299 block_init(iscsi_block_init);