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Merge remote-tracking branch 'kwolf/block-stable' into staging

stable-1.0
Anthony Liguori 15 years ago
parent
7197390a0b 33ebad1263
commit
54dcd0b37e
6 changed files with 209 additions and 44 deletions
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  1. 20
      hw/ide/atapi.c
  2. 128
      hw/scsi-bus.c
  3. 10
      hw/scsi-defs.h
  4. 37
      hw/scsi-disk.c
  5. 2
      hw/scsi.h
  6. 56
      qemu-doc.texi

20
hw/ide/atapi.c
View File

@ -695,12 +695,7 @@ static void cmd_mode_sense(IDEState *s, uint8_t *buf)
int action, code;
int max_len;
if (buf[0] == GPCMD_MODE_SENSE_10) {
max_len = ube16_to_cpu(buf + 7);
} else {
max_len = buf[4];
}
max_len = ube16_to_cpu(buf + 7);
action = buf[2] >> 6;
code = buf[2] & 0x3f;
@ -708,7 +703,7 @@ static void cmd_mode_sense(IDEState *s, uint8_t *buf)
case 0: /* current values */
switch(code) {
case MODE_PAGE_R_W_ERROR: /* error recovery */
cpu_to_ube16(&buf[0], 16 + 6);
cpu_to_ube16(&buf[0], 16 - 2);
buf[2] = 0x70;
buf[3] = 0;
buf[4] = 0;
@ -727,7 +722,7 @@ static void cmd_mode_sense(IDEState *s, uint8_t *buf)
ide_atapi_cmd_reply(s, 16, max_len);
break;
case MODE_PAGE_AUDIO_CTL:
cpu_to_ube16(&buf[0], 24 + 6);
cpu_to_ube16(&buf[0], 24 - 2);
buf[2] = 0x70;
buf[3] = 0;
buf[4] = 0;
@ -746,7 +741,7 @@ static void cmd_mode_sense(IDEState *s, uint8_t *buf)
ide_atapi_cmd_reply(s, 24, max_len);
break;
case MODE_PAGE_CAPABILITIES:
cpu_to_ube16(&buf[0], 28 + 6);
cpu_to_ube16(&buf[0], 30 - 2);
buf[2] = 0x70;
buf[3] = 0;
buf[4] = 0;
@ -755,7 +750,7 @@ static void cmd_mode_sense(IDEState *s, uint8_t *buf)
buf[7] = 0;
buf[8] = MODE_PAGE_CAPABILITIES;
buf[9] = 28 - 10;
buf[9] = 30 - 10;
buf[10] = 0x3b; /* read CDR/CDRW/DVDROM/DVDR/DVDRAM */
buf[11] = 0x00;
@ -777,7 +772,9 @@ static void cmd_mode_sense(IDEState *s, uint8_t *buf)
buf[25] = 0;
buf[26] = 0;
buf[27] = 0;
ide_atapi_cmd_reply(s, 28, max_len);
buf[28] = 0;
buf[29] = 0;
ide_atapi_cmd_reply(s, 30, max_len);
break;
default:
goto error_cmd;
@ -1043,7 +1040,6 @@ static const struct {
[ 0x00 ] = { cmd_test_unit_ready, CHECK_READY },
[ 0x03 ] = { cmd_request_sense, ALLOW_UA },
[ 0x12 ] = { cmd_inquiry, ALLOW_UA },
[ 0x1a ] = { cmd_mode_sense, /* (6) */ 0 },
[ 0x1b ] = { cmd_start_stop_unit, 0 }, /* [1] */
[ 0x1e ] = { cmd_prevent_allow_medium_removal, 0 },
[ 0x25 ] = { cmd_read_cdvd_capacity, CHECK_READY },

128
hw/scsi-bus.c
View File

@ -9,8 +9,6 @@
static char *scsibus_get_fw_dev_path(DeviceState *dev);
static int scsi_req_parse(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf);
static void scsi_req_dequeue(SCSIRequest *req);
static int scsi_build_sense(uint8_t *in_buf, int in_len,
uint8_t *buf, int len, bool fixed);
static struct BusInfo scsi_bus_info = {
.name = "SCSI",
@ -502,7 +500,7 @@ SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun,
hba_private);
} else if (lun != d->lun ||
buf[0] == REPORT_LUNS ||
buf[0] == REQUEST_SENSE) {
(buf[0] == REQUEST_SENSE && (d->sense_len || cmd.xfer < 4))) {
req = scsi_req_alloc(&reqops_target_command, d, tag, lun,
hba_private);
} else {
@ -649,6 +647,31 @@ static void scsi_req_dequeue(SCSIRequest *req)
}
}
static int scsi_get_performance_length(int num_desc, int type, int data_type)
{
/* MMC-6, paragraph 6.7. */
switch (type) {
case 0:
if ((data_type & 3) == 0) {
/* Each descriptor is as in Table 295 - Nominal performance. */
return 16 * num_desc + 8;
} else {
/* Each descriptor is as in Table 296 - Exceptions. */
return 6 * num_desc + 8;
}
case 1:
case 4:
case 5:
return 8 * num_desc + 8;
case 2:
return 2048 * num_desc + 8;
case 3:
return 16 * num_desc + 8;
default:
return 8;
}
}
static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
{
switch (buf[0] >> 5) {
@ -666,11 +689,11 @@ static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
cmd->len = 10;
break;
case 4:
cmd->xfer = ldl_be_p(&buf[10]);
cmd->xfer = ldl_be_p(&buf[10]) & 0xffffffffULL;
cmd->len = 16;
break;
case 5:
cmd->xfer = ldl_be_p(&buf[6]);
cmd->xfer = ldl_be_p(&buf[6]) & 0xffffffffULL;
cmd->len = 12;
break;
default:
@ -681,8 +704,9 @@ static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
case TEST_UNIT_READY:
case REWIND:
case START_STOP:
case SEEK_6:
case SET_CAPACITY:
case WRITE_FILEMARKS:
case WRITE_FILEMARKS_16:
case SPACE:
case RESERVE:
case RELEASE:
@ -691,6 +715,8 @@ static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
case VERIFY_10:
case SEEK_10:
case SYNCHRONIZE_CACHE:
case SYNCHRONIZE_CACHE_16:
case LOCATE_16:
case LOCK_UNLOCK_CACHE:
case LOAD_UNLOAD:
case SET_CD_SPEED:
@ -698,6 +724,11 @@ static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
case WRITE_LONG_10:
case MOVE_MEDIUM:
case UPDATE_BLOCK:
case RESERVE_TRACK:
case SET_READ_AHEAD:
case PRE_FETCH:
case PRE_FETCH_16:
case ALLOW_OVERWRITE:
cmd->xfer = 0;
break;
case MODE_SENSE:
@ -711,14 +742,13 @@ static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
case READ_BLOCK_LIMITS:
cmd->xfer = 6;
break;
case READ_POSITION:
cmd->xfer = 20;
break;
case SEND_VOLUME_TAG:
cmd->xfer *= 40;
break;
case MEDIUM_SCAN:
cmd->xfer *= 8;
/* GPCMD_SET_STREAMING from multimedia commands. */
if (dev->type == TYPE_ROM) {
cmd->xfer = buf[10] | (buf[9] << 8);
} else {
cmd->xfer = buf[9] | (buf[8] << 8);
}
break;
case WRITE_10:
case WRITE_VERIFY_10:
@ -737,9 +767,39 @@ static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
case READ_16:
cmd->xfer *= dev->blocksize;
break;
case FORMAT_UNIT:
/* MMC mandates the parameter list to be 12-bytes long. Parameters
* for block devices are restricted to the header right now. */
if (dev->type == TYPE_ROM && (buf[1] & 16)) {
cmd->xfer = 12;
} else {
cmd->xfer = (buf[1] & 16) == 0 ? 0 : (buf[1] & 32 ? 8 : 4);
}
break;
case INQUIRY:
case RECEIVE_DIAGNOSTIC:
case SEND_DIAGNOSTIC:
cmd->xfer = buf[4] | (buf[3] << 8);
break;
case READ_CD:
case READ_BUFFER:
case WRITE_BUFFER:
case SEND_CUE_SHEET:
cmd->xfer = buf[8] | (buf[7] << 8) | (buf[6] << 16);
break;
case PERSISTENT_RESERVE_OUT:
cmd->xfer = ldl_be_p(&buf[5]) & 0xffffffffULL;
break;
case ERASE_12:
if (dev->type == TYPE_ROM) {
/* MMC command GET PERFORMANCE. */
cmd->xfer = scsi_get_performance_length(buf[9] | (buf[8] << 8),
buf[10], buf[1] & 0x1f);
}
break;
case MECHANISM_STATUS:
case READ_DVD_STRUCTURE:
case SEND_DVD_STRUCTURE:
case MAINTENANCE_OUT:
case MAINTENANCE_IN:
if (dev->type == TYPE_ROM) {
@ -755,6 +815,10 @@ static int scsi_req_stream_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *bu
{
switch (buf[0]) {
/* stream commands */
case ERASE_12:
case ERASE_16:
cmd->xfer = 0;
break;
case READ_6:
case READ_REVERSE:
case RECOVER_BUFFERED_DATA:
@ -770,6 +834,15 @@ static int scsi_req_stream_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *bu
cmd->len = 6;
cmd->xfer = 0;
break;
case SPACE_16:
cmd->xfer = buf[13] | (buf[12] << 8);
break;
case READ_POSITION:
cmd->xfer = buf[8] | (buf[7] << 8);
break;
case FORMAT_UNIT:
cmd->xfer = buf[4] | (buf[3] << 8);
break;
/* generic commands */
default:
return scsi_req_length(cmd, dev, buf);
@ -809,6 +882,8 @@ static void scsi_cmd_xfer_mode(SCSICommand *cmd)
case SEARCH_LOW_12:
case MEDIUM_SCAN:
case SEND_VOLUME_TAG:
case SEND_CUE_SHEET:
case SEND_DVD_STRUCTURE:
case PERSISTENT_RESERVE_OUT:
case MAINTENANCE_OUT:
cmd->mode = SCSI_XFER_TO_DEV;
@ -835,7 +910,7 @@ static uint64_t scsi_cmd_lba(SCSICommand *cmd)
case 1:
case 2:
case 5:
lba = ldl_be_p(&buf[2]);
lba = ldl_be_p(&buf[2]) & 0xffffffffULL;
break;
case 4:
lba = ldq_be_p(&buf[2]);
@ -1036,7 +1111,7 @@ static const char *scsi_command_name(uint8_t cmd)
[ REASSIGN_BLOCKS ] = "REASSIGN_BLOCKS",
[ READ_6 ] = "READ_6",
[ WRITE_6 ] = "WRITE_6",
[ SEEK_6 ] = "SEEK_6",
[ SET_CAPACITY ] = "SET_CAPACITY",
[ READ_REVERSE ] = "READ_REVERSE",
[ WRITE_FILEMARKS ] = "WRITE_FILEMARKS",
[ SPACE ] = "SPACE",
@ -1064,7 +1139,7 @@ static const char *scsi_command_name(uint8_t cmd)
[ SEARCH_EQUAL ] = "SEARCH_EQUAL",
[ SEARCH_LOW ] = "SEARCH_LOW",
[ SET_LIMITS ] = "SET_LIMITS",
[ PRE_FETCH ] = "PRE_FETCH",
[ PRE_FETCH ] = "PRE_FETCH/READ_POSITION",
/* READ_POSITION and PRE_FETCH use the same operation code */
[ SYNCHRONIZE_CACHE ] = "SYNCHRONIZE_CACHE",
[ LOCK_UNLOCK_CACHE ] = "LOCK_UNLOCK_CACHE",
@ -1101,9 +1176,11 @@ static const char *scsi_command_name(uint8_t cmd)
[ WRITE_16 ] = "WRITE_16",
[ WRITE_VERIFY_16 ] = "WRITE_VERIFY_16",
[ VERIFY_16 ] = "VERIFY_16",
[ SYNCHRONIZE_CACHE_16 ] = "SYNCHRONIZE_CACHE_16",
[ PRE_FETCH_16 ] = "PRE_FETCH_16",
[ SYNCHRONIZE_CACHE_16 ] = "SPACE_16/SYNCHRONIZE_CACHE_16",
/* SPACE_16 and SYNCHRONIZE_CACHE_16 use the same operation code */
[ LOCATE_16 ] = "LOCATE_16",
[ WRITE_SAME_16 ] = "WRITE_SAME_16",
[ WRITE_SAME_16 ] = "ERASE_16/WRITE_SAME_16",
/* ERASE_16 and WRITE_SAME_16 use the same operation code */
[ SERVICE_ACTION_IN_16 ] = "SERVICE_ACTION_IN_16",
[ WRITE_LONG_16 ] = "WRITE_LONG_16",
@ -1113,6 +1190,8 @@ static const char *scsi_command_name(uint8_t cmd)
[ LOAD_UNLOAD ] = "LOAD_UNLOAD",
[ READ_12 ] = "READ_12",
[ WRITE_12 ] = "WRITE_12",
[ ERASE_12 ] = "ERASE_12/GET_PERFORMANCE",
/* ERASE_12 and GET_PERFORMANCE use the same operation code */
[ SERVICE_ACTION_IN_12 ] = "SERVICE_ACTION_IN_12",
[ WRITE_VERIFY_12 ] = "WRITE_VERIFY_12",
[ VERIFY_12 ] = "VERIFY_12",
@ -1120,9 +1199,18 @@ static const char *scsi_command_name(uint8_t cmd)
[ SEARCH_EQUAL_12 ] = "SEARCH_EQUAL_12",
[ SEARCH_LOW_12 ] = "SEARCH_LOW_12",
[ READ_ELEMENT_STATUS ] = "READ_ELEMENT_STATUS",
[ SEND_VOLUME_TAG ] = "SEND_VOLUME_TAG",
[ SEND_VOLUME_TAG ] = "SEND_VOLUME_TAG/SET_STREAMING",
/* SEND_VOLUME_TAG and SET_STREAMING use the same operation code */
[ READ_CD ] = "READ_CD",
[ READ_DEFECT_DATA_12 ] = "READ_DEFECT_DATA_12",
[ READ_DVD_STRUCTURE ] = "READ_DVD_STRUCTURE",
[ RESERVE_TRACK ] = "RESERVE_TRACK",
[ SEND_CUE_SHEET ] = "SEND_CUE_SHEET",
[ SEND_DVD_STRUCTURE ] = "SEND_DVD_STRUCTURE",
[ SET_CD_SPEED ] = "SET_CD_SPEED",
[ SET_READ_AHEAD ] = "SET_READ_AHEAD",
[ ALLOW_OVERWRITE ] = "ALLOW_OVERWRITE",
[ MECHANISM_STATUS ] = "MECHANISM_STATUS",
};
if (cmd >= ARRAY_SIZE(names) || names[cmd] == NULL)
@ -1279,7 +1367,7 @@ static char *scsibus_get_fw_dev_path(DeviceState *dev)
SCSIDevice *d = DO_UPCAST(SCSIDevice, qdev, dev);
char path[100];
snprintf(path, sizeof(path), "%s@%d:%d:%d", qdev_fw_name(dev),
snprintf(path, sizeof(path), "%s@%d,%d,%d", qdev_fw_name(dev),
d->channel, d->id, d->lun);
return strdup(path);

10
hw/scsi-defs.h
View File

@ -32,7 +32,7 @@
#define REASSIGN_BLOCKS 0x07
#define READ_6 0x08
#define WRITE_6 0x0a
#define SEEK_6 0x0b
#define SET_CAPACITY 0x0b
#define READ_REVERSE 0x0f
#define WRITE_FILEMARKS 0x10
#define SPACE 0x11
@ -81,14 +81,17 @@
#define GET_EVENT_STATUS_NOTIFICATION 0x4a
#define LOG_SELECT 0x4c
#define LOG_SENSE 0x4d
#define RESERVE_TRACK 0x53
#define MODE_SELECT_10 0x55
#define RESERVE_10 0x56
#define RELEASE_10 0x57
#define MODE_SENSE_10 0x5a
#define SEND_CUE_SHEET 0x5d
#define PERSISTENT_RESERVE_IN 0x5e
#define PERSISTENT_RESERVE_OUT 0x5f
#define VARLENGTH_CDB 0x7f
#define WRITE_FILEMARKS_16 0x80
#define ALLOW_OVERWRITE 0x82
#define EXTENDED_COPY 0x83
#define ATA_PASSTHROUGH 0x85
#define ACCESS_CONTROL_IN 0x86
@ -98,6 +101,8 @@
#define WRITE_16 0x8a
#define WRITE_VERIFY_16 0x8e
#define VERIFY_16 0x8f
#define PRE_FETCH_16 0x90
#define SPACE_16 0x91
#define SYNCHRONIZE_CACHE_16 0x91
#define LOCATE_16 0x92
#define WRITE_SAME_16 0x93
@ -110,9 +115,11 @@
#define MAINTENANCE_OUT 0xa4
#define MOVE_MEDIUM 0xa5
#define LOAD_UNLOAD 0xa6
#define SET_READ_AHEAD 0xa7
#define READ_12 0xa8
#define WRITE_12 0xaa
#define SERVICE_ACTION_IN_12 0xab
#define ERASE_12 0xac
#define READ_DVD_STRUCTURE 0xad
#define WRITE_VERIFY_12 0xae
#define VERIFY_12 0xaf
@ -125,6 +132,7 @@
#define SET_CD_SPEED 0xbb
#define MECHANISM_STATUS 0xbd
#define READ_CD 0xbe
#define SEND_DVD_STRUCTURE 0xbf
/*
* SERVICE ACTION IN subcodes

37
hw/scsi-disk.c
View File

@ -797,7 +797,7 @@ static int mode_sense_page(SCSIDiskState *s, int page, uint8_t **p_outbuf,
break;
}
/* if a geometry hint is available, use it */
bdrv_get_geometry_hint(bdrv, &cylinders, &heads, &secs);
bdrv_guess_geometry(bdrv, &cylinders, &heads, &secs);
p[2] = (cylinders >> 16) & 0xff;
p[3] = (cylinders >> 8) & 0xff;
p[4] = cylinders & 0xff;
@ -831,7 +831,7 @@ static int mode_sense_page(SCSIDiskState *s, int page, uint8_t **p_outbuf,
p[2] = 5000 >> 8;
p[3] = 5000 & 0xff;
/* if a geometry hint is available, use it */
bdrv_get_geometry_hint(bdrv, &cylinders, &heads, &secs);
bdrv_guess_geometry(bdrv, &cylinders, &heads, &secs);
p[4] = heads & 0xff;
p[5] = secs & 0xff;
p[6] = s->qdev.blocksize >> 8;
@ -956,8 +956,9 @@ static int scsi_disk_emulate_mode_sense(SCSIDiskReq *r, uint8_t *outbuf)
p += 8;
}
/* MMC prescribes that CD/DVD drives have no block descriptors. */
bdrv_get_geometry(s->qdev.conf.bs, &nb_sectors);
if (!dbd && nb_sectors) {
if (!dbd && s->qdev.type == TYPE_DISK && nb_sectors) {
if (r->req.cmd.buf[0] == MODE_SENSE) {
outbuf[3] = 8; /* Block descriptor length */
} else { /* MODE_SENSE_10 */
@ -1178,6 +1179,11 @@ static int scsi_disk_emulate_command(SCSIDiskReq *r)
outbuf[7] = 0;
buflen = 8;
break;
case REQUEST_SENSE:
/* Just return "NO SENSE". */
buflen = scsi_build_sense(NULL, 0, outbuf, r->buflen,
(req->cmd.buf[1] & 1) == 0);
break;
case MECHANISM_STATUS:
buflen = scsi_emulate_mechanism_status(s, outbuf);
if (buflen < 0) {
@ -1312,6 +1318,7 @@ static int32_t scsi_send_command(SCSIRequest *req, uint8_t *buf)
case GET_EVENT_STATUS_NOTIFICATION:
case MECHANISM_STATUS:
case SERVICE_ACTION_IN_16:
case REQUEST_SENSE:
case VERIFY_10:
rc = scsi_disk_emulate_command(r);
if (rc < 0) {
@ -1374,10 +1381,8 @@ static int32_t scsi_send_command(SCSIRequest *req, uint8_t *buf)
goto fail;
}
break;
case SEEK_6:
case SEEK_10:
DPRINTF("Seek(%d) (sector %" PRId64 ")\n", command == SEEK_6 ? 6 : 10,
r->req.cmd.lba);
DPRINTF("Seek(10) (sector %" PRId64 ")\n", r->req.cmd.lba);
if (r->req.cmd.lba > s->qdev.max_lba) {
goto illegal_lba;
}
@ -1408,8 +1413,6 @@ static int32_t scsi_send_command(SCSIRequest *req, uint8_t *buf)
}
break;
case REQUEST_SENSE:
abort();
default:
DPRINTF("Unknown SCSI command (%2.2x)\n", buf[0]);
scsi_check_condition(r, SENSE_CODE(INVALID_OPCODE));
@ -1553,7 +1556,7 @@ static int scsi_initfn(SCSIDevice *dev)
bdrv_set_buffer_alignment(s->qdev.conf.bs, s->qdev.blocksize);
bdrv_iostatus_enable(s->qdev.conf.bs);
add_boot_device_path(s->qdev.conf.bootindex, &dev->qdev, ",0");
add_boot_device_path(s->qdev.conf.bootindex, &dev->qdev, NULL);
return 0;
}
@ -1700,8 +1703,20 @@ static SCSIRequest *scsi_block_new_request(SCSIDevice *d, uint32_t tag,
case WRITE_VERIFY_10:
case WRITE_VERIFY_12:
case WRITE_VERIFY_16:
return scsi_req_alloc(&scsi_disk_reqops, &s->qdev, tag, lun,
hba_private);
/* MMC writing cannot be done via pread/pwrite, because it sometimes
* involves writing beyond the maximum LBA or to negative LBA (lead-in).
* And once you do these writes, reading from the block device is
* unreliable, too. It is even possible that reads deliver random data
* from the host page cache (this is probably a Linux bug).
*
* We might use scsi_disk_reqops as long as no writing commands are
* seen, but performance usually isn't paramount on optical media. So,
* just make scsi-block operate the same as scsi-generic for them.
*/
if (s->qdev.type != TYPE_ROM) {
return scsi_req_alloc(&scsi_disk_reqops, &s->qdev, tag, lun,
hba_private);
}
}
return scsi_req_alloc(&scsi_generic_req_ops, &s->qdev, tag, lun,

2
hw/scsi.h
View File

@ -179,6 +179,8 @@ extern const struct SCSISense sense_code_DEVICE_INTERNAL_RESET;
#define SENSE_CODE(x) sense_code_ ## x
int scsi_sense_valid(SCSISense sense);
int scsi_build_sense(uint8_t *in_buf, int in_len,
uint8_t *buf, int len, bool fixed);
SCSIRequest *scsi_req_alloc(const SCSIReqOps *reqops, SCSIDevice *d,
uint32_t tag, uint32_t lun, void *hba_private);

56
qemu-doc.texi
View File

@ -421,6 +421,7 @@ snapshots.
* disk_images_fat_images:: Virtual FAT disk images
* disk_images_nbd:: NBD access
* disk_images_sheepdog:: Sheepdog disk images
* disk_images_iscsi:: iSCSI LUNs
@end menu
@node disk_images_quickstart
@ -695,6 +696,61 @@ qemu-img create sheepdog:@var{hostname}:@var{port}:@var{image} @var{size}
qemu sheepdog:@var{hostname}:@var{port}:@var{image}
@end example
@node disk_images_iscsi
@subsection iSCSI LUNs
iSCSI is a popular protocol used to access SCSI devices across a computer
network.
There are two different ways iSCSI devices can be used by QEMU.
The first method is to mount the iSCSI LUN on the host, and make it appear as
any other ordinary SCSI device on the host and then to access this device as a
/dev/sd device from QEMU. How to do this differs between host OSes.
The second method involves using the iSCSI initiator that is built into
QEMU. This provides a mechanism that works the same way regardless of which
host OS you are running QEMU on. This section will describe this second method
of using iSCSI together with QEMU.
In QEMU, iSCSI devices are described using special iSCSI URLs
@example
URL syntax:
iscsi://[<username>[%<password>]@@]<host>[:<port>]/<target-iqn-name>/<lun>
@end example
Username and password are optional and only used if your target is set up
using CHAP authentication for access control.
Alternatively the username and password can also be set via environment
variables to have these not show up in the process list
@example
export LIBISCSI_CHAP_USERNAME=<username>
export LIBISCSI_CHAP_PASSWORD=<password>
iscsi://<host>/<target-iqn-name>/<lun>
@end example
Howto set up a simple iSCSI target on loopback and accessing it via QEMU:
@example
This example shows how to set up an iSCSI target with one CDROM and one DISK
using the Linux STGT software target. This target is available on Red Hat based
systems as the package 'scsi-target-utils'.
tgtd --iscsi portal=127.0.0.1:3260
tgtadm --lld iscsi --op new --mode target --tid 1 -T iqn.qemu.test
tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 1 \
-b /IMAGES/disk.img --device-type=disk
tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 2 \
-b /IMAGES/cd.iso --device-type=cd
tgtadm --lld iscsi --op bind --mode target --tid 1 -I ALL
qemu-system-i386 -boot d -drive file=iscsi://127.0.0.1/iqn.qemu.test/1 \
-cdrom iscsi://127.0.0.1/iqn.qemu.test/2
@end example
@node pcsys_network
@section Network emulation

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