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-error.h"
  31 #include "block_int.h"
  32 #include "trace.h"
  33 #include "hw/scsi-defs.h"
  34
  35 #include <iscsi/iscsi.h>
  36 #include <iscsi/scsi-lowlevel.h>
  37
  38 #ifdef __linux__
  39 #include <scsi/sg.h>
  40 #include <hw/scsi-defs.h>
  41 #endif
  42
  43 typedef struct IscsiLun {
  44     struct iscsi_context *iscsi;
  45     int lun;
  46     enum scsi_inquiry_peripheral_device_type type;
  47     int block_size;
  48     uint64_t num_blocks;
  49     int events;
  50 } IscsiLun;
  51
  52 typedef struct IscsiAIOCB {
  53     BlockDriverAIOCB common;
  54     QEMUIOVector *qiov;
  55     QEMUBH *bh;
  56     IscsiLun *iscsilun;
  57     struct scsi_task *task;
  58     uint8_t *buf;
  59     int status;
  60     int canceled;
  61     size_t read_size;
  62     size_t read_offset;
  63 #ifdef __linux__
  64     sg_io_hdr_t *ioh;
  65 #endif
  66 } IscsiAIOCB;
  67
  68 static void
  69 iscsi_bh_cb(void *p)
  70 {
  71     IscsiAIOCB *acb = p;
  72
  73     qemu_bh_delete(acb->bh);
  74
  75     if (acb->canceled == 0) {
  76         acb->common.cb(acb->common.opaque, acb->status);
  77     }
  78
  79     if (acb->task != NULL) {
  80         scsi_free_scsi_task(acb->task);
  81         acb->task = NULL;
  82     }
  83
  84     qemu_aio_release(acb);
  85 }
  86
  87 static void
  88 iscsi_schedule_bh(IscsiAIOCB *acb)
  89 {
  90     if (acb->bh) {
  91         return;
  92     }
  93     acb->bh = qemu_bh_new(iscsi_bh_cb, acb);
  94     qemu_bh_schedule(acb->bh);
  95 }
  96
  97
  98 static void
  99 iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
 100                     void *private_data)
 101 {
 102     IscsiAIOCB *acb = private_data;
 103
 104     acb->status = -ECANCELED;
 105     iscsi_schedule_bh(acb);
 106 }
 107
 108 static void
 109 iscsi_aio_cancel(BlockDriverAIOCB *blockacb)
 110 {
 111     IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
 112     IscsiLun *iscsilun = acb->iscsilun;
 113
 114     if (acb->status != -EINPROGRESS) {
 115         return;
 116     }
 117
 118     acb->canceled = 1;
 119
 120     /* send a task mgmt call to the target to cancel the task on the target */
 121     iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
 122                                      iscsi_abort_task_cb, acb);
 123
 124     while (acb->status == -EINPROGRESS) {
 125         qemu_aio_wait();
 126     }
 127 }
 128
 129 static const AIOCBInfo iscsi_aiocb_info = {
 130     .aiocb_size         = sizeof(IscsiAIOCB),
 131     .cancel             = iscsi_aio_cancel,
 132 };
 133
 134
 135 static void iscsi_process_read(void *arg);
 136 static void iscsi_process_write(void *arg);
 137
 138 static int iscsi_process_flush(void *arg)
 139 {
 140     IscsiLun *iscsilun = arg;
 141
 142     return iscsi_queue_length(iscsilun->iscsi) > 0;
 143 }
 144
 145 static void
 146 iscsi_set_events(IscsiLun *iscsilun)
 147 {
 148     struct iscsi_context *iscsi = iscsilun->iscsi;
 149     int ev;
 150
 151     /* We always register a read handler.  */
 152     ev = POLLIN;
 153     ev |= iscsi_which_events(iscsi);
 154     if (ev != iscsilun->events) {
 155         qemu_aio_set_fd_handler(iscsi_get_fd(iscsi),
 156                       iscsi_process_read,
 157                       (ev & POLLOUT) ? iscsi_process_write : NULL,
 158                       iscsi_process_flush,
 159                       iscsilun);
 160
 161     }
 162
 163     iscsilun->events = ev;
 164 }
 165
 166 static void
 167 iscsi_process_read(void *arg)
 168 {
 169     IscsiLun *iscsilun = arg;
 170     struct iscsi_context *iscsi = iscsilun->iscsi;
 171
 172     iscsi_service(iscsi, POLLIN);
 173     iscsi_set_events(iscsilun);
 174 }
 175
 176 static void
 177 iscsi_process_write(void *arg)
 178 {
 179     IscsiLun *iscsilun = arg;
 180     struct iscsi_context *iscsi = iscsilun->iscsi;
 181
 182     iscsi_service(iscsi, POLLOUT);
 183     iscsi_set_events(iscsilun);
 184 }
 185
 186
 187 static void
 188 iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status,
 189                      void *command_data, void *opaque)
 190 {
 191     IscsiAIOCB *acb = opaque;
 192
 193     trace_iscsi_aio_write16_cb(iscsi, status, acb, acb->canceled);
 194
 195     g_free(acb->buf);
 196
 197     if (acb->canceled != 0) {
 198         return;
 199     }
 200
 201     acb->status = 0;
 202     if (status < 0) {
 203         error_report("Failed to write16 data to iSCSI lun. %s",
 204                      iscsi_get_error(iscsi));
 205         acb->status = -EIO;
 206     }
 207
 208     iscsi_schedule_bh(acb);
 209 }
 210
 211 static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
 212 {
 213     return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
 214 }
 215
 216 static BlockDriverAIOCB *
 217 iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num,
 218                  QEMUIOVector *qiov, int nb_sectors,
 219                  BlockDriverCompletionFunc *cb,
 220                  void *opaque)
 221 {
 222     IscsiLun *iscsilun = bs->opaque;
 223     struct iscsi_context *iscsi = iscsilun->iscsi;
 224     IscsiAIOCB *acb;
 225     size_t size;
 226     uint32_t num_sectors;
 227     uint64_t lba;
 228     struct iscsi_data data;
 229
 230     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 231     trace_iscsi_aio_writev(iscsi, sector_num, nb_sectors, opaque, acb);
 232
 233     acb->iscsilun = iscsilun;
 234     acb->qiov     = qiov;
 235
 236     acb->canceled   = 0;
 237     acb->bh         = NULL;
 238     acb->status     = -EINPROGRESS;
 239
 240     /* XXX we should pass the iovec to write16 to avoid the extra copy */
 241     /* this will allow us to get rid of 'buf' completely */
 242     size = nb_sectors * BDRV_SECTOR_SIZE;
 243     acb->buf = g_malloc(size);
 244     qemu_iovec_to_buf(acb->qiov, 0, acb->buf, size);
 245
 246     acb->task = malloc(sizeof(struct scsi_task));
 247     if (acb->task == NULL) {
 248         error_report("iSCSI: Failed to allocate task for scsi WRITE16 "
 249                      "command. %s", iscsi_get_error(iscsi));
 250         qemu_aio_release(acb);
 251         return NULL;
 252     }
 253     memset(acb->task, 0, sizeof(struct scsi_task));
 254
 255     acb->task->xfer_dir = SCSI_XFER_WRITE;
 256     acb->task->cdb_size = 16;
 257     acb->task->cdb[0] = 0x8a;
 258     lba = sector_qemu2lun(sector_num, iscsilun);
 259     *(uint32_t *)&acb->task->cdb[2]  = htonl(lba >> 32);
 260     *(uint32_t *)&acb->task->cdb[6]  = htonl(lba & 0xffffffff);
 261     num_sectors = size / iscsilun->block_size;
 262     *(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors);
 263     acb->task->expxferlen = size;
 264
 265     data.data = acb->buf;
 266     data.size = size;
 267
 268     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
 269                                  iscsi_aio_write16_cb,
 270                                  &data,
 271                                  acb) != 0) {
 272         scsi_free_scsi_task(acb->task);
 273         g_free(acb->buf);
 274         qemu_aio_release(acb);
 275         return NULL;
 276     }
 277
 278     iscsi_set_events(iscsilun);
 279
 280     return &acb->common;
 281 }
 282
 283 static void
 284 iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status,
 285                     void *command_data, void *opaque)
 286 {
 287     IscsiAIOCB *acb = opaque;
 288
 289     trace_iscsi_aio_read16_cb(iscsi, status, acb, acb->canceled);
 290
 291     if (acb->canceled != 0) {
 292         return;
 293     }
 294
 295     acb->status = 0;
 296     if (status != 0) {
 297         error_report("Failed to read16 data from iSCSI lun. %s",
 298                      iscsi_get_error(iscsi));
 299         acb->status = -EIO;
 300     }
 301
 302     iscsi_schedule_bh(acb);
 303 }
 304
 305 static BlockDriverAIOCB *
 306 iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num,
 307                 QEMUIOVector *qiov, int nb_sectors,
 308                 BlockDriverCompletionFunc *cb,
 309                 void *opaque)
 310 {
 311     IscsiLun *iscsilun = bs->opaque;
 312     struct iscsi_context *iscsi = iscsilun->iscsi;
 313     IscsiAIOCB *acb;
 314     size_t qemu_read_size;
 315     int i;
 316     uint64_t lba;
 317     uint32_t num_sectors;
 318
 319     qemu_read_size = BDRV_SECTOR_SIZE * (size_t)nb_sectors;
 320
 321     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 322     trace_iscsi_aio_readv(iscsi, sector_num, nb_sectors, opaque, acb);
 323
 324     acb->iscsilun = iscsilun;
 325     acb->qiov     = qiov;
 326
 327     acb->canceled    = 0;
 328     acb->bh          = NULL;
 329     acb->status      = -EINPROGRESS;
 330     acb->read_size   = qemu_read_size;
 331     acb->buf         = NULL;
 332
 333     /* If LUN blocksize is bigger than BDRV_BLOCK_SIZE a read from QEMU
 334      * may be misaligned to the LUN, so we may need to read some extra
 335      * data.
 336      */
 337     acb->read_offset = 0;
 338     if (iscsilun->block_size > BDRV_SECTOR_SIZE) {
 339         uint64_t bdrv_offset = BDRV_SECTOR_SIZE * sector_num;
 340
 341         acb->read_offset  = bdrv_offset % iscsilun->block_size;
 342     }
 343
 344     num_sectors  = (qemu_read_size + iscsilun->block_size
 345                     + acb->read_offset - 1)
 346                     / iscsilun->block_size;
 347
 348     acb->task = malloc(sizeof(struct scsi_task));
 349     if (acb->task == NULL) {
 350         error_report("iSCSI: Failed to allocate task for scsi READ16 "
 351                      "command. %s", iscsi_get_error(iscsi));
 352         qemu_aio_release(acb);
 353         return NULL;
 354     }
 355     memset(acb->task, 0, sizeof(struct scsi_task));
 356
 357     acb->task->xfer_dir = SCSI_XFER_READ;
 358     lba = sector_qemu2lun(sector_num, iscsilun);
 359     acb->task->expxferlen = qemu_read_size;
 360
 361     switch (iscsilun->type) {
 362     case TYPE_DISK:
 363         acb->task->cdb_size = 16;
 364         acb->task->cdb[0]  = 0x88;
 365         *(uint32_t *)&acb->task->cdb[2]  = htonl(lba >> 32);
 366         *(uint32_t *)&acb->task->cdb[6]  = htonl(lba & 0xffffffff);
 367         *(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors);
 368         break;
 369     default:
 370         acb->task->cdb_size = 10;
 371         acb->task->cdb[0]  = 0x28;
 372         *(uint32_t *)&acb->task->cdb[2] = htonl(lba);
 373         *(uint16_t *)&acb->task->cdb[7] = htons(num_sectors);
 374         break;
 375     }
 376
 377     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
 378                                  iscsi_aio_read16_cb,
 379                                  NULL,
 380                                  acb) != 0) {
 381         scsi_free_scsi_task(acb->task);
 382         qemu_aio_release(acb);
 383         return NULL;
 384     }
 385
 386     for (i = 0; i < acb->qiov->niov; i++) {
 387         scsi_task_add_data_in_buffer(acb->task,
 388                 acb->qiov->iov[i].iov_len,
 389                 acb->qiov->iov[i].iov_base);
 390     }
 391
 392     iscsi_set_events(iscsilun);
 393
 394     return &acb->common;
 395 }
 396
 397
 398 static void
 399 iscsi_synccache10_cb(struct iscsi_context *iscsi, int status,
 400                      void *command_data, void *opaque)
 401 {
 402     IscsiAIOCB *acb = opaque;
 403
 404     if (acb->canceled != 0) {
 405         return;
 406     }
 407
 408     acb->status = 0;
 409     if (status < 0) {
 410         error_report("Failed to sync10 data on iSCSI lun. %s",
 411                      iscsi_get_error(iscsi));
 412         acb->status = -EIO;
 413     }
 414
 415     iscsi_schedule_bh(acb);
 416 }
 417
 418 static BlockDriverAIOCB *
 419 iscsi_aio_flush(BlockDriverState *bs,
 420                 BlockDriverCompletionFunc *cb, void *opaque)
 421 {
 422     IscsiLun *iscsilun = bs->opaque;
 423     struct iscsi_context *iscsi = iscsilun->iscsi;
 424     IscsiAIOCB *acb;
 425
 426     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 427
 428     acb->iscsilun = iscsilun;
 429     acb->canceled   = 0;
 430     acb->bh         = NULL;
 431     acb->status     = -EINPROGRESS;
 432
 433     acb->task = iscsi_synchronizecache10_task(iscsi, iscsilun->lun,
 434                                          0, 0, 0, 0,
 435                                          iscsi_synccache10_cb,
 436                                          acb);
 437     if (acb->task == NULL) {
 438         error_report("iSCSI: Failed to send synchronizecache10 command. %s",
 439                      iscsi_get_error(iscsi));
 440         qemu_aio_release(acb);
 441         return NULL;
 442     }
 443
 444     iscsi_set_events(iscsilun);
 445
 446     return &acb->common;
 447 }
 448
 449 static void
 450 iscsi_unmap_cb(struct iscsi_context *iscsi, int status,
 451                      void *command_data, void *opaque)
 452 {
 453     IscsiAIOCB *acb = opaque;
 454
 455     if (acb->canceled != 0) {
 456         return;
 457     }
 458
 459     acb->status = 0;
 460     if (status < 0) {
 461         error_report("Failed to unmap data on iSCSI lun. %s",
 462                      iscsi_get_error(iscsi));
 463         acb->status = -EIO;
 464     }
 465
 466     iscsi_schedule_bh(acb);
 467 }
 468
 469 static BlockDriverAIOCB *
 470 iscsi_aio_discard(BlockDriverState *bs,
 471                   int64_t sector_num, int nb_sectors,
 472                   BlockDriverCompletionFunc *cb, void *opaque)
 473 {
 474     IscsiLun *iscsilun = bs->opaque;
 475     struct iscsi_context *iscsi = iscsilun->iscsi;
 476     IscsiAIOCB *acb;
 477     struct unmap_list list[1];
 478
 479     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 480
 481     acb->iscsilun = iscsilun;
 482     acb->canceled   = 0;
 483     acb->bh         = NULL;
 484     acb->status     = -EINPROGRESS;
 485
 486     list[0].lba = sector_qemu2lun(sector_num, iscsilun);
 487     list[0].num = nb_sectors * BDRV_SECTOR_SIZE / iscsilun->block_size;
 488
 489     acb->task = iscsi_unmap_task(iscsi, iscsilun->lun,
 490                                  0, 0, &list[0], 1,
 491                                  iscsi_unmap_cb,
 492                                  acb);
 493     if (acb->task == NULL) {
 494         error_report("iSCSI: Failed to send unmap command. %s",
 495                      iscsi_get_error(iscsi));
 496         qemu_aio_release(acb);
 497         return NULL;
 498     }
 499
 500     iscsi_set_events(iscsilun);
 501
 502     return &acb->common;
 503 }
 504
 505 #ifdef __linux__
 506 static void
 507 iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
 508                      void *command_data, void *opaque)
 509 {
 510     IscsiAIOCB *acb = opaque;
 511
 512     if (acb->canceled != 0) {
 513         return;
 514     }
 515
 516     acb->status = 0;
 517     if (status < 0) {
 518         error_report("Failed to ioctl(SG_IO) to iSCSI lun. %s",
 519                      iscsi_get_error(iscsi));
 520         acb->status = -EIO;
 521     }
 522
 523     acb->ioh->driver_status = 0;
 524     acb->ioh->host_status   = 0;
 525     acb->ioh->resid         = 0;
 526
 527 #define SG_ERR_DRIVER_SENSE    0x08
 528
 529     if (status == SCSI_STATUS_CHECK_CONDITION && acb->task->datain.size >= 2) {
 530         int ss;
 531
 532         acb->ioh->driver_status |= SG_ERR_DRIVER_SENSE;
 533
 534         acb->ioh->sb_len_wr = acb->task->datain.size - 2;
 535         ss = (acb->ioh->mx_sb_len >= acb->ioh->sb_len_wr) ?
 536              acb->ioh->mx_sb_len : acb->ioh->sb_len_wr;
 537         memcpy(acb->ioh->sbp, &acb->task->datain.data[2], ss);
 538     }
 539
 540     iscsi_schedule_bh(acb);
 541 }
 542
 543 static BlockDriverAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
 544         unsigned long int req, void *buf,
 545         BlockDriverCompletionFunc *cb, void *opaque)
 546 {
 547     IscsiLun *iscsilun = bs->opaque;
 548     struct iscsi_context *iscsi = iscsilun->iscsi;
 549     struct iscsi_data data;
 550     IscsiAIOCB *acb;
 551
 552     assert(req == SG_IO);
 553
 554     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
 555
 556     acb->iscsilun = iscsilun;
 557     acb->canceled    = 0;
 558     acb->bh          = NULL;
 559     acb->status      = -EINPROGRESS;
 560     acb->buf         = NULL;
 561     acb->ioh         = buf;
 562
 563     acb->task = malloc(sizeof(struct scsi_task));
 564     if (acb->task == NULL) {
 565         error_report("iSCSI: Failed to allocate task for scsi command. %s",
 566                      iscsi_get_error(iscsi));
 567         qemu_aio_release(acb);
 568         return NULL;
 569     }
 570     memset(acb->task, 0, sizeof(struct scsi_task));
 571
 572     switch (acb->ioh->dxfer_direction) {
 573     case SG_DXFER_TO_DEV:
 574         acb->task->xfer_dir = SCSI_XFER_WRITE;
 575         break;
 576     case SG_DXFER_FROM_DEV:
 577         acb->task->xfer_dir = SCSI_XFER_READ;
 578         break;
 579     default:
 580         acb->task->xfer_dir = SCSI_XFER_NONE;
 581         break;
 582     }
 583
 584     acb->task->cdb_size = acb->ioh->cmd_len;
 585     memcpy(&acb->task->cdb[0], acb->ioh->cmdp, acb->ioh->cmd_len);
 586     acb->task->expxferlen = acb->ioh->dxfer_len;
 587
 588     if (acb->task->xfer_dir == SCSI_XFER_WRITE) {
 589         data.data = acb->ioh->dxferp;
 590         data.size = acb->ioh->dxfer_len;
 591     }
 592     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
 593                                  iscsi_aio_ioctl_cb,
 594                                  (acb->task->xfer_dir == SCSI_XFER_WRITE) ?
 595                                      &data : NULL,
 596                                  acb) != 0) {
 597         scsi_free_scsi_task(acb->task);
 598         qemu_aio_release(acb);
 599         return NULL;
 600     }
 601
 602     /* tell libiscsi to read straight into the buffer we got from ioctl */
 603     if (acb->task->xfer_dir == SCSI_XFER_READ) {
 604         scsi_task_add_data_in_buffer(acb->task,
 605                                      acb->ioh->dxfer_len,
 606                                      acb->ioh->dxferp);
 607     }
 608
 609     iscsi_set_events(iscsilun);
 610
 611     return &acb->common;
 612 }
 613
 614
 615 static void ioctl_cb(void *opaque, int status)
 616 {
 617     int *p_status = opaque;
 618     *p_status = status;
 619 }
 620
 621 static int iscsi_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
 622 {
 623     IscsiLun *iscsilun = bs->opaque;
 624     int status;
 625
 626     switch (req) {
 627     case SG_GET_VERSION_NUM:
 628         *(int *)buf = 30000;
 629         break;
 630     case SG_GET_SCSI_ID:
 631         ((struct sg_scsi_id *)buf)->scsi_type = iscsilun->type;
 632         break;
 633     case SG_IO:
 634         status = -EINPROGRESS;
 635         iscsi_aio_ioctl(bs, req, buf, ioctl_cb, &status);
 636
 637         while (status == -EINPROGRESS) {
 638             qemu_aio_wait();
 639         }
 640
 641         return 0;
 642     default:
 643         return -1;
 644     }
 645     return 0;
 646 }
 647 #endif
 648
 649 static int64_t
 650 iscsi_getlength(BlockDriverState *bs)
 651 {
 652     IscsiLun *iscsilun = bs->opaque;
 653     int64_t len;
 654
 655     len  = iscsilun->num_blocks;
 656     len *= iscsilun->block_size;
 657
 658     return len;
 659 }
 660
 661 static int parse_chap(struct iscsi_context *iscsi, const char *target)
 662 {
 663     QemuOptsList *list;
 664     QemuOpts *opts;
 665     const char *user = NULL;
 666     const char *password = NULL;
 667
 668     list = qemu_find_opts("iscsi");
 669     if (!list) {
 670         return 0;
 671     }
 672
 673     opts = qemu_opts_find(list, target);
 674     if (opts == NULL) {
 675         opts = QTAILQ_FIRST(&list->head);
 676         if (!opts) {
 677             return 0;
 678         }
 679     }
 680
 681     user = qemu_opt_get(opts, "user");
 682     if (!user) {
 683         return 0;
 684     }
 685
 686     password = qemu_opt_get(opts, "password");
 687     if (!password) {
 688         error_report("CHAP username specified but no password was given");
 689         return -1;
 690     }
 691
 692     if (iscsi_set_initiator_username_pwd(iscsi, user, password)) {
 693         error_report("Failed to set initiator username and password");
 694         return -1;
 695     }
 696
 697     return 0;
 698 }
 699
 700 static void parse_header_digest(struct iscsi_context *iscsi, const char *target)
 701 {
 702     QemuOptsList *list;
 703     QemuOpts *opts;
 704     const char *digest = NULL;
 705
 706     list = qemu_find_opts("iscsi");
 707     if (!list) {
 708         return;
 709     }
 710
 711     opts = qemu_opts_find(list, target);
 712     if (opts == NULL) {
 713         opts = QTAILQ_FIRST(&list->head);
 714         if (!opts) {
 715             return;
 716         }
 717     }
 718
 719     digest = qemu_opt_get(opts, "header-digest");
 720     if (!digest) {
 721         return;
 722     }
 723
 724     if (!strcmp(digest, "CRC32C")) {
 725         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C);
 726     } else if (!strcmp(digest, "NONE")) {
 727         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE);
 728     } else if (!strcmp(digest, "CRC32C-NONE")) {
 729         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C_NONE);
 730     } else if (!strcmp(digest, "NONE-CRC32C")) {
 731         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
 732     } else {
 733         error_report("Invalid header-digest setting : %s", digest);
 734     }
 735 }
 736
 737 static char *parse_initiator_name(const char *target)
 738 {
 739     QemuOptsList *list;
 740     QemuOpts *opts;
 741     const char *name = NULL;
 742     const char *iscsi_name = qemu_get_vm_name();
 743
 744     list = qemu_find_opts("iscsi");
 745     if (list) {
 746         opts = qemu_opts_find(list, target);
 747         if (!opts) {
 748             opts = QTAILQ_FIRST(&list->head);
 749         }
 750         if (opts) {
 751             name = qemu_opt_get(opts, "initiator-name");
 752         }
 753     }
 754
 755     if (name) {
 756         return g_strdup(name);
 757     } else {
 758         return g_strdup_printf("iqn.2008-11.org.linux-kvm%s%s",
 759                                iscsi_name ? ":" : "",
 760                                iscsi_name ? iscsi_name : "");
 761     }
 762 }
 763
 764 /*
 765  * We support iscsi url's on the form
 766  * iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>
 767  */
 768 static int iscsi_open(BlockDriverState *bs, const char *filename, int flags)
 769 {
 770     IscsiLun *iscsilun = bs->opaque;
 771     struct iscsi_context *iscsi = NULL;
 772     struct iscsi_url *iscsi_url = NULL;
 773     struct scsi_task *task = NULL;
 774     struct scsi_inquiry_standard *inq = NULL;
 775     struct scsi_readcapacity10 *rc10 = NULL;
 776     struct scsi_readcapacity16 *rc16 = NULL;
 777     char *initiator_name = NULL;
 778     int ret;
 779
 780     if ((BDRV_SECTOR_SIZE % 512) != 0) {
 781         error_report("iSCSI: Invalid BDRV_SECTOR_SIZE. "
 782                      "BDRV_SECTOR_SIZE(%lld) is not a multiple "
 783                      "of 512", BDRV_SECTOR_SIZE);
 784         return -EINVAL;
 785     }
 786
 787     iscsi_url = iscsi_parse_full_url(iscsi, filename);
 788     if (iscsi_url == NULL) {
 789         error_report("Failed to parse URL : %s", filename);
 790         ret = -EINVAL;
 791         goto out;
 792     }
 793
 794     memset(iscsilun, 0, sizeof(IscsiLun));
 795
 796     initiator_name = parse_initiator_name(iscsi_url->target);
 797
 798     iscsi = iscsi_create_context(initiator_name);
 799     if (iscsi == NULL) {
 800         error_report("iSCSI: Failed to create iSCSI context.");
 801         ret = -ENOMEM;
 802         goto out;
 803     }
 804
 805     if (iscsi_set_targetname(iscsi, iscsi_url->target)) {
 806         error_report("iSCSI: Failed to set target name.");
 807         ret = -EINVAL;
 808         goto out;
 809     }
 810
 811     if (iscsi_url->user != NULL) {
 812         ret = iscsi_set_initiator_username_pwd(iscsi, iscsi_url->user,
 813                                               iscsi_url->passwd);
 814         if (ret != 0) {
 815             error_report("Failed to set initiator username and password");
 816             ret = -EINVAL;
 817             goto out;
 818         }
 819     }
 820
 821     /* check if we got CHAP username/password via the options */
 822     if (parse_chap(iscsi, iscsi_url->target) != 0) {
 823         error_report("iSCSI: Failed to set CHAP user/password");
 824         ret = -EINVAL;
 825         goto out;
 826     }
 827
 828     if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) != 0) {
 829         error_report("iSCSI: Failed to set session type to normal.");
 830         ret = -EINVAL;
 831         goto out;
 832     }
 833
 834     iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
 835
 836     /* check if we got HEADER_DIGEST via the options */
 837     parse_header_digest(iscsi, iscsi_url->target);
 838
 839     if (iscsi_full_connect_sync(iscsi, iscsi_url->portal, iscsi_url->lun) != 0) {
 840         error_report("iSCSI: Failed to connect to LUN : %s",
 841             iscsi_get_error(iscsi));
 842         ret = -EINVAL;
 843         goto out;
 844     }
 845
 846     iscsilun->iscsi = iscsi;
 847     iscsilun->lun   = iscsi_url->lun;
 848
 849     task = iscsi_inquiry_sync(iscsi, iscsilun->lun, 0, 0, 36);
 850
 851     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
 852         error_report("iSCSI: failed to send inquiry command.");
 853         ret = -EINVAL;
 854         goto out;
 855     }
 856
 857     inq = scsi_datain_unmarshall(task);
 858     if (inq == NULL) {
 859         error_report("iSCSI: Failed to unmarshall inquiry data.");
 860         ret = -EINVAL;
 861         goto out;
 862     }
 863
 864     iscsilun->type = inq->periperal_device_type;
 865
 866     scsi_free_scsi_task(task);
 867
 868     switch (iscsilun->type) {
 869     case TYPE_DISK:
 870         task = iscsi_readcapacity16_sync(iscsi, iscsilun->lun);
 871         if (task == NULL || task->status != SCSI_STATUS_GOOD) {
 872             error_report("iSCSI: failed to send readcapacity16 command.");
 873             ret = -EINVAL;
 874             goto out;
 875         }
 876         rc16 = scsi_datain_unmarshall(task);
 877         if (rc16 == NULL) {
 878             error_report("iSCSI: Failed to unmarshall readcapacity16 data.");
 879             ret = -EINVAL;
 880             goto out;
 881         }
 882         iscsilun->block_size = rc16->block_length;
 883         iscsilun->num_blocks = rc16->returned_lba + 1;
 884         break;
 885     case TYPE_ROM:
 886         task = iscsi_readcapacity10_sync(iscsi, iscsilun->lun, 0, 0);
 887         if (task == NULL || task->status != SCSI_STATUS_GOOD) {
 888             error_report("iSCSI: failed to send readcapacity10 command.");
 889             ret = -EINVAL;
 890             goto out;
 891         }
 892         rc10 = scsi_datain_unmarshall(task);
 893         if (rc10 == NULL) {
 894             error_report("iSCSI: Failed to unmarshall readcapacity10 data.");
 895             ret = -EINVAL;
 896             goto out;
 897         }
 898         iscsilun->block_size = rc10->block_size;
 899         if (rc10->lba == 0) {
 900             /* blank disk loaded */
 901             iscsilun->num_blocks = 0;
 902         } else {
 903             iscsilun->num_blocks = rc10->lba + 1;
 904         }
 905         break;
 906     default:
 907         break;
 908     }
 909
 910     bs->total_sectors    = iscsilun->num_blocks *
 911                            iscsilun->block_size / BDRV_SECTOR_SIZE ;
 912
 913     /* Medium changer or tape. We dont have any emulation for this so this must
 914      * be sg ioctl compatible. We force it to be sg, otherwise qemu will try
 915      * to read from the device to guess the image format.
 916      */
 917     if (iscsilun->type == TYPE_MEDIUM_CHANGER ||
 918         iscsilun->type == TYPE_TAPE) {
 919         bs->sg = 1;
 920     }
 921
 922     ret = 0;
 923
 924 out:
 925     if (initiator_name != NULL) {
 926         g_free(initiator_name);
 927     }
 928     if (iscsi_url != NULL) {
 929         iscsi_destroy_url(iscsi_url);
 930     }
 931     if (task != NULL) {
 932         scsi_free_scsi_task(task);
 933     }
 934
 935     if (ret) {
 936         if (iscsi != NULL) {
 937             iscsi_destroy_context(iscsi);
 938         }
 939         memset(iscsilun, 0, sizeof(IscsiLun));
 940     }
 941     return ret;
 942 }
 943
 944 static void iscsi_close(BlockDriverState *bs)
 945 {
 946     IscsiLun *iscsilun = bs->opaque;
 947     struct iscsi_context *iscsi = iscsilun->iscsi;
 948
 949     qemu_aio_set_fd_handler(iscsi_get_fd(iscsi), NULL, NULL, NULL, NULL);
 950     iscsi_destroy_context(iscsi);
 951     memset(iscsilun, 0, sizeof(IscsiLun));
 952 }
 953
 954 static BlockDriver bdrv_iscsi = {
 955     .format_name     = "iscsi",
 956     .protocol_name   = "iscsi",
 957
 958     .instance_size   = sizeof(IscsiLun),
 959     .bdrv_file_open  = iscsi_open,
 960     .bdrv_close      = iscsi_close,
 961
 962     .bdrv_getlength  = iscsi_getlength,
 963
 964     .bdrv_aio_readv  = iscsi_aio_readv,
 965     .bdrv_aio_writev = iscsi_aio_writev,
 966     .bdrv_aio_flush  = iscsi_aio_flush,
 967
 968     .bdrv_aio_discard = iscsi_aio_discard,
 969
 970 #ifdef __linux__
 971     .bdrv_ioctl       = iscsi_ioctl,
 972     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
 973 #endif
 974 };
 975
 976 static void iscsi_block_init(void)
 977 {
 978     bdrv_register(&bdrv_iscsi);
 979 }
 980
 981 block_init(iscsi_block_init);