qemu/block/iscsi.c
Anthony Liguori 444dbc381b Merge remote-tracking branch 'kwolf/for-anthony' into staging
* kwolf/for-anthony:
  block: remove keep_read_only flag from BlockDriverState struct
  block: convert bdrv_commit() to use bdrv_reopen()
  block: vpc image file reopen
  block: vdi image file reopen
  block: vmdk image file reopen
  block: qcow image file reopen
  block: qcow2 image file reopen
  block: qed image file reopen
  block: raw image file reopen
  block: raw-posix image file reopen
  block: purge s->aligned_buf and s->aligned_buf_size from raw-posix.c
  block: use BDRV_O_NOCACHE instead of s->aligned_buf in raw-posix.c
  block: do not parse BDRV_O_CACHE_WB in block drivers
  block: move open flag parsing in raw block drivers to helper functions
  block: move aio initialization into a helper function
  block: Framework for reopening files safely
  block: make bdrv_set_enable_write_cache() modify open_flags
  block: correctly set the keep_read_only flag
  blockdev: preserve readonly and snapshot states across media changes
2012-09-25 16:06:16 -05:00

1093 lines
29 KiB
C

/*
* QEMU Block driver for iSCSI images
*
* Copyright (c) 2010-2011 Ronnie Sahlberg <ronniesahlberg@gmail.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "config-host.h"
#include <poll.h>
#include <arpa/inet.h>
#include "qemu-common.h"
#include "qemu-error.h"
#include "block_int.h"
#include "trace.h"
#include "hw/scsi-defs.h"
#include <iscsi/iscsi.h>
#include <iscsi/scsi-lowlevel.h>
#ifdef __linux__
#include <scsi/sg.h>
#include <hw/scsi-defs.h>
#endif
typedef struct IscsiLun {
struct iscsi_context *iscsi;
int lun;
enum scsi_inquiry_peripheral_device_type type;
int block_size;
uint64_t num_blocks;
int events;
} IscsiLun;
typedef struct IscsiAIOCB {
BlockDriverAIOCB common;
QEMUIOVector *qiov;
QEMUBH *bh;
IscsiLun *iscsilun;
struct scsi_task *task;
uint8_t *buf;
int status;
int canceled;
size_t read_size;
size_t read_offset;
#ifdef __linux__
sg_io_hdr_t *ioh;
#endif
} IscsiAIOCB;
struct IscsiTask {
IscsiLun *iscsilun;
BlockDriverState *bs;
int status;
int complete;
};
static void
iscsi_bh_cb(void *p)
{
IscsiAIOCB *acb = p;
qemu_bh_delete(acb->bh);
if (acb->canceled == 0) {
acb->common.cb(acb->common.opaque, acb->status);
}
if (acb->task != NULL) {
scsi_free_scsi_task(acb->task);
acb->task = NULL;
}
qemu_aio_release(acb);
}
static void
iscsi_schedule_bh(IscsiAIOCB *acb)
{
if (acb->bh) {
return;
}
acb->bh = qemu_bh_new(iscsi_bh_cb, acb);
qemu_bh_schedule(acb->bh);
}
static void
iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
void *private_data)
{
IscsiAIOCB *acb = private_data;
acb->status = -ECANCELED;
iscsi_schedule_bh(acb);
}
static void
iscsi_aio_cancel(BlockDriverAIOCB *blockacb)
{
IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
IscsiLun *iscsilun = acb->iscsilun;
if (acb->status != -EINPROGRESS) {
return;
}
acb->canceled = 1;
/* send a task mgmt call to the target to cancel the task on the target */
iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
iscsi_abort_task_cb, acb);
while (acb->status == -EINPROGRESS) {
qemu_aio_wait();
}
}
static AIOPool iscsi_aio_pool = {
.aiocb_size = sizeof(IscsiAIOCB),
.cancel = iscsi_aio_cancel,
};
static void iscsi_process_read(void *arg);
static void iscsi_process_write(void *arg);
static int iscsi_process_flush(void *arg)
{
IscsiLun *iscsilun = arg;
return iscsi_queue_length(iscsilun->iscsi) > 0;
}
static void
iscsi_set_events(IscsiLun *iscsilun)
{
struct iscsi_context *iscsi = iscsilun->iscsi;
int ev;
/* We always register a read handler. */
ev = POLLIN;
ev |= iscsi_which_events(iscsi);
if (ev != iscsilun->events) {
qemu_aio_set_fd_handler(iscsi_get_fd(iscsi),
iscsi_process_read,
(ev & POLLOUT) ? iscsi_process_write : NULL,
iscsi_process_flush,
iscsilun);
}
iscsilun->events = ev;
}
static void
iscsi_process_read(void *arg)
{
IscsiLun *iscsilun = arg;
struct iscsi_context *iscsi = iscsilun->iscsi;
iscsi_service(iscsi, POLLIN);
iscsi_set_events(iscsilun);
}
static void
iscsi_process_write(void *arg)
{
IscsiLun *iscsilun = arg;
struct iscsi_context *iscsi = iscsilun->iscsi;
iscsi_service(iscsi, POLLOUT);
iscsi_set_events(iscsilun);
}
static void
iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status,
void *command_data, void *opaque)
{
IscsiAIOCB *acb = opaque;
trace_iscsi_aio_write16_cb(iscsi, status, acb, acb->canceled);
g_free(acb->buf);
if (acb->canceled != 0) {
return;
}
acb->status = 0;
if (status < 0) {
error_report("Failed to write16 data to iSCSI lun. %s",
iscsi_get_error(iscsi));
acb->status = -EIO;
}
iscsi_schedule_bh(acb);
}
static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
{
return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
}
static BlockDriverAIOCB *
iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num,
QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb,
void *opaque)
{
IscsiLun *iscsilun = bs->opaque;
struct iscsi_context *iscsi = iscsilun->iscsi;
IscsiAIOCB *acb;
size_t size;
uint32_t num_sectors;
uint64_t lba;
struct iscsi_data data;
acb = qemu_aio_get(&iscsi_aio_pool, bs, cb, opaque);
trace_iscsi_aio_writev(iscsi, sector_num, nb_sectors, opaque, acb);
acb->iscsilun = iscsilun;
acb->qiov = qiov;
acb->canceled = 0;
acb->bh = NULL;
acb->status = -EINPROGRESS;
/* XXX we should pass the iovec to write16 to avoid the extra copy */
/* this will allow us to get rid of 'buf' completely */
size = nb_sectors * BDRV_SECTOR_SIZE;
acb->buf = g_malloc(size);
qemu_iovec_to_buf(acb->qiov, 0, acb->buf, size);
acb->task = malloc(sizeof(struct scsi_task));
if (acb->task == NULL) {
error_report("iSCSI: Failed to allocate task for scsi WRITE16 "
"command. %s", iscsi_get_error(iscsi));
qemu_aio_release(acb);
return NULL;
}
memset(acb->task, 0, sizeof(struct scsi_task));
acb->task->xfer_dir = SCSI_XFER_WRITE;
acb->task->cdb_size = 16;
acb->task->cdb[0] = 0x8a;
lba = sector_qemu2lun(sector_num, iscsilun);
*(uint32_t *)&acb->task->cdb[2] = htonl(lba >> 32);
*(uint32_t *)&acb->task->cdb[6] = htonl(lba & 0xffffffff);
num_sectors = size / iscsilun->block_size;
*(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors);
acb->task->expxferlen = size;
data.data = acb->buf;
data.size = size;
if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
iscsi_aio_write16_cb,
&data,
acb) != 0) {
scsi_free_scsi_task(acb->task);
g_free(acb->buf);
qemu_aio_release(acb);
return NULL;
}
iscsi_set_events(iscsilun);
return &acb->common;
}
static void
iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status,
void *command_data, void *opaque)
{
IscsiAIOCB *acb = opaque;
trace_iscsi_aio_read16_cb(iscsi, status, acb, acb->canceled);
if (acb->canceled != 0) {
return;
}
acb->status = 0;
if (status != 0) {
error_report("Failed to read16 data from iSCSI lun. %s",
iscsi_get_error(iscsi));
acb->status = -EIO;
}
iscsi_schedule_bh(acb);
}
static BlockDriverAIOCB *
iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num,
QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb,
void *opaque)
{
IscsiLun *iscsilun = bs->opaque;
struct iscsi_context *iscsi = iscsilun->iscsi;
IscsiAIOCB *acb;
size_t qemu_read_size;
int i;
uint64_t lba;
uint32_t num_sectors;
qemu_read_size = BDRV_SECTOR_SIZE * (size_t)nb_sectors;
acb = qemu_aio_get(&iscsi_aio_pool, bs, cb, opaque);
trace_iscsi_aio_readv(iscsi, sector_num, nb_sectors, opaque, acb);
acb->iscsilun = iscsilun;
acb->qiov = qiov;
acb->canceled = 0;
acb->bh = NULL;
acb->status = -EINPROGRESS;
acb->read_size = qemu_read_size;
acb->buf = NULL;
/* If LUN blocksize is bigger than BDRV_BLOCK_SIZE a read from QEMU
* may be misaligned to the LUN, so we may need to read some extra
* data.
*/
acb->read_offset = 0;
if (iscsilun->block_size > BDRV_SECTOR_SIZE) {
uint64_t bdrv_offset = BDRV_SECTOR_SIZE * sector_num;
acb->read_offset = bdrv_offset % iscsilun->block_size;
}
num_sectors = (qemu_read_size + iscsilun->block_size
+ acb->read_offset - 1)
/ iscsilun->block_size;
acb->task = malloc(sizeof(struct scsi_task));
if (acb->task == NULL) {
error_report("iSCSI: Failed to allocate task for scsi READ16 "
"command. %s", iscsi_get_error(iscsi));
qemu_aio_release(acb);
return NULL;
}
memset(acb->task, 0, sizeof(struct scsi_task));
acb->task->xfer_dir = SCSI_XFER_READ;
lba = sector_qemu2lun(sector_num, iscsilun);
acb->task->expxferlen = qemu_read_size;
switch (iscsilun->type) {
case TYPE_DISK:
acb->task->cdb_size = 16;
acb->task->cdb[0] = 0x88;
*(uint32_t *)&acb->task->cdb[2] = htonl(lba >> 32);
*(uint32_t *)&acb->task->cdb[6] = htonl(lba & 0xffffffff);
*(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors);
break;
default:
acb->task->cdb_size = 10;
acb->task->cdb[0] = 0x28;
*(uint32_t *)&acb->task->cdb[2] = htonl(lba);
*(uint16_t *)&acb->task->cdb[7] = htons(num_sectors);
break;
}
if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
iscsi_aio_read16_cb,
NULL,
acb) != 0) {
scsi_free_scsi_task(acb->task);
qemu_aio_release(acb);
return NULL;
}
for (i = 0; i < acb->qiov->niov; i++) {
scsi_task_add_data_in_buffer(acb->task,
acb->qiov->iov[i].iov_len,
acb->qiov->iov[i].iov_base);
}
iscsi_set_events(iscsilun);
return &acb->common;
}
static void
iscsi_synccache10_cb(struct iscsi_context *iscsi, int status,
void *command_data, void *opaque)
{
IscsiAIOCB *acb = opaque;
if (acb->canceled != 0) {
return;
}
acb->status = 0;
if (status < 0) {
error_report("Failed to sync10 data on iSCSI lun. %s",
iscsi_get_error(iscsi));
acb->status = -EIO;
}
iscsi_schedule_bh(acb);
}
static BlockDriverAIOCB *
iscsi_aio_flush(BlockDriverState *bs,
BlockDriverCompletionFunc *cb, void *opaque)
{
IscsiLun *iscsilun = bs->opaque;
struct iscsi_context *iscsi = iscsilun->iscsi;
IscsiAIOCB *acb;
acb = qemu_aio_get(&iscsi_aio_pool, bs, cb, opaque);
acb->iscsilun = iscsilun;
acb->canceled = 0;
acb->bh = NULL;
acb->status = -EINPROGRESS;
acb->task = iscsi_synchronizecache10_task(iscsi, iscsilun->lun,
0, 0, 0, 0,
iscsi_synccache10_cb,
acb);
if (acb->task == NULL) {
error_report("iSCSI: Failed to send synchronizecache10 command. %s",
iscsi_get_error(iscsi));
qemu_aio_release(acb);
return NULL;
}
iscsi_set_events(iscsilun);
return &acb->common;
}
static void
iscsi_unmap_cb(struct iscsi_context *iscsi, int status,
void *command_data, void *opaque)
{
IscsiAIOCB *acb = opaque;
if (acb->canceled != 0) {
return;
}
acb->status = 0;
if (status < 0) {
error_report("Failed to unmap data on iSCSI lun. %s",
iscsi_get_error(iscsi));
acb->status = -EIO;
}
iscsi_schedule_bh(acb);
}
static BlockDriverAIOCB *
iscsi_aio_discard(BlockDriverState *bs,
int64_t sector_num, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque)
{
IscsiLun *iscsilun = bs->opaque;
struct iscsi_context *iscsi = iscsilun->iscsi;
IscsiAIOCB *acb;
struct unmap_list list[1];
acb = qemu_aio_get(&iscsi_aio_pool, bs, cb, opaque);
acb->iscsilun = iscsilun;
acb->canceled = 0;
acb->bh = NULL;
acb->status = -EINPROGRESS;
list[0].lba = sector_qemu2lun(sector_num, iscsilun);
list[0].num = nb_sectors * BDRV_SECTOR_SIZE / iscsilun->block_size;
acb->task = iscsi_unmap_task(iscsi, iscsilun->lun,
0, 0, &list[0], 1,
iscsi_unmap_cb,
acb);
if (acb->task == NULL) {
error_report("iSCSI: Failed to send unmap command. %s",
iscsi_get_error(iscsi));
qemu_aio_release(acb);
return NULL;
}
iscsi_set_events(iscsilun);
return &acb->common;
}
#ifdef __linux__
static void
iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
void *command_data, void *opaque)
{
IscsiAIOCB *acb = opaque;
if (acb->canceled != 0) {
return;
}
acb->status = 0;
if (status < 0) {
error_report("Failed to ioctl(SG_IO) to iSCSI lun. %s",
iscsi_get_error(iscsi));
acb->status = -EIO;
}
acb->ioh->driver_status = 0;
acb->ioh->host_status = 0;
acb->ioh->resid = 0;
#define SG_ERR_DRIVER_SENSE 0x08
if (status == SCSI_STATUS_CHECK_CONDITION && acb->task->datain.size >= 2) {
int ss;
acb->ioh->driver_status |= SG_ERR_DRIVER_SENSE;
acb->ioh->sb_len_wr = acb->task->datain.size - 2;
ss = (acb->ioh->mx_sb_len >= acb->ioh->sb_len_wr) ?
acb->ioh->mx_sb_len : acb->ioh->sb_len_wr;
memcpy(acb->ioh->sbp, &acb->task->datain.data[2], ss);
}
iscsi_schedule_bh(acb);
}
static BlockDriverAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
unsigned long int req, void *buf,
BlockDriverCompletionFunc *cb, void *opaque)
{
IscsiLun *iscsilun = bs->opaque;
struct iscsi_context *iscsi = iscsilun->iscsi;
struct iscsi_data data;
IscsiAIOCB *acb;
assert(req == SG_IO);
acb = qemu_aio_get(&iscsi_aio_pool, bs, cb, opaque);
acb->iscsilun = iscsilun;
acb->canceled = 0;
acb->bh = NULL;
acb->status = -EINPROGRESS;
acb->buf = NULL;
acb->ioh = buf;
acb->task = malloc(sizeof(struct scsi_task));
if (acb->task == NULL) {
error_report("iSCSI: Failed to allocate task for scsi command. %s",
iscsi_get_error(iscsi));
qemu_aio_release(acb);
return NULL;
}
memset(acb->task, 0, sizeof(struct scsi_task));
switch (acb->ioh->dxfer_direction) {
case SG_DXFER_TO_DEV:
acb->task->xfer_dir = SCSI_XFER_WRITE;
break;
case SG_DXFER_FROM_DEV:
acb->task->xfer_dir = SCSI_XFER_READ;
break;
default:
acb->task->xfer_dir = SCSI_XFER_NONE;
break;
}
acb->task->cdb_size = acb->ioh->cmd_len;
memcpy(&acb->task->cdb[0], acb->ioh->cmdp, acb->ioh->cmd_len);
acb->task->expxferlen = acb->ioh->dxfer_len;
if (acb->task->xfer_dir == SCSI_XFER_WRITE) {
data.data = acb->ioh->dxferp;
data.size = acb->ioh->dxfer_len;
}
if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
iscsi_aio_ioctl_cb,
(acb->task->xfer_dir == SCSI_XFER_WRITE) ?
&data : NULL,
acb) != 0) {
scsi_free_scsi_task(acb->task);
qemu_aio_release(acb);
return NULL;
}
/* tell libiscsi to read straight into the buffer we got from ioctl */
if (acb->task->xfer_dir == SCSI_XFER_READ) {
scsi_task_add_data_in_buffer(acb->task,
acb->ioh->dxfer_len,
acb->ioh->dxferp);
}
iscsi_set_events(iscsilun);
return &acb->common;
}
static void ioctl_cb(void *opaque, int status)
{
int *p_status = opaque;
*p_status = status;
}
static int iscsi_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
{
IscsiLun *iscsilun = bs->opaque;
int status;
switch (req) {
case SG_GET_VERSION_NUM:
*(int *)buf = 30000;
break;
case SG_GET_SCSI_ID:
((struct sg_scsi_id *)buf)->scsi_type = iscsilun->type;
break;
case SG_IO:
status = -EINPROGRESS;
iscsi_aio_ioctl(bs, req, buf, ioctl_cb, &status);
while (status == -EINPROGRESS) {
qemu_aio_wait();
}
return 0;
default:
return -1;
}
return 0;
}
#endif
static int64_t
iscsi_getlength(BlockDriverState *bs)
{
IscsiLun *iscsilun = bs->opaque;
int64_t len;
len = iscsilun->num_blocks;
len *= iscsilun->block_size;
return len;
}
static void
iscsi_readcapacity16_cb(struct iscsi_context *iscsi, int status,
void *command_data, void *opaque)
{
struct IscsiTask *itask = opaque;
struct scsi_readcapacity16 *rc16;
struct scsi_task *task = command_data;
if (status != 0) {
error_report("iSCSI: Failed to read capacity of iSCSI lun. %s",
iscsi_get_error(iscsi));
itask->status = 1;
itask->complete = 1;
scsi_free_scsi_task(task);
return;
}
rc16 = scsi_datain_unmarshall(task);
if (rc16 == NULL) {
error_report("iSCSI: Failed to unmarshall readcapacity16 data.");
itask->status = 1;
itask->complete = 1;
scsi_free_scsi_task(task);
return;
}
itask->iscsilun->block_size = rc16->block_length;
itask->iscsilun->num_blocks = rc16->returned_lba + 1;
itask->bs->total_sectors = itask->iscsilun->num_blocks *
itask->iscsilun->block_size / BDRV_SECTOR_SIZE ;
itask->status = 0;
itask->complete = 1;
scsi_free_scsi_task(task);
}
static void
iscsi_readcapacity10_cb(struct iscsi_context *iscsi, int status,
void *command_data, void *opaque)
{
struct IscsiTask *itask = opaque;
struct scsi_readcapacity10 *rc10;
struct scsi_task *task = command_data;
if (status != 0) {
error_report("iSCSI: Failed to read capacity of iSCSI lun. %s",
iscsi_get_error(iscsi));
itask->status = 1;
itask->complete = 1;
scsi_free_scsi_task(task);
return;
}
rc10 = scsi_datain_unmarshall(task);
if (rc10 == NULL) {
error_report("iSCSI: Failed to unmarshall readcapacity10 data.");
itask->status = 1;
itask->complete = 1;
scsi_free_scsi_task(task);
return;
}
itask->iscsilun->block_size = rc10->block_size;
if (rc10->lba == 0) {
/* blank disk loaded */
itask->iscsilun->num_blocks = 0;
} else {
itask->iscsilun->num_blocks = rc10->lba + 1;
}
itask->bs->total_sectors = itask->iscsilun->num_blocks *
itask->iscsilun->block_size / BDRV_SECTOR_SIZE ;
itask->status = 0;
itask->complete = 1;
scsi_free_scsi_task(task);
}
static void
iscsi_inquiry_cb(struct iscsi_context *iscsi, int status, void *command_data,
void *opaque)
{
struct IscsiTask *itask = opaque;
struct scsi_task *task = command_data;
struct scsi_inquiry_standard *inq;
if (status != 0) {
itask->status = 1;
itask->complete = 1;
scsi_free_scsi_task(task);
return;
}
inq = scsi_datain_unmarshall(task);
if (inq == NULL) {
error_report("iSCSI: Failed to unmarshall inquiry data.");
itask->status = 1;
itask->complete = 1;
scsi_free_scsi_task(task);
return;
}
itask->iscsilun->type = inq->periperal_device_type;
scsi_free_scsi_task(task);
switch (itask->iscsilun->type) {
case TYPE_DISK:
task = iscsi_readcapacity16_task(iscsi, itask->iscsilun->lun,
iscsi_readcapacity16_cb, opaque);
if (task == NULL) {
error_report("iSCSI: failed to send readcapacity16 command.");
itask->status = 1;
itask->complete = 1;
return;
}
break;
case TYPE_ROM:
task = iscsi_readcapacity10_task(iscsi, itask->iscsilun->lun,
0, 0,
iscsi_readcapacity10_cb, opaque);
if (task == NULL) {
error_report("iSCSI: failed to send readcapacity16 command.");
itask->status = 1;
itask->complete = 1;
return;
}
break;
default:
itask->status = 0;
itask->complete = 1;
}
}
static void
iscsi_connect_cb(struct iscsi_context *iscsi, int status, void *command_data,
void *opaque)
{
struct IscsiTask *itask = opaque;
struct scsi_task *task;
if (status != 0) {
itask->status = 1;
itask->complete = 1;
return;
}
task = iscsi_inquiry_task(iscsi, itask->iscsilun->lun,
0, 0, 36,
iscsi_inquiry_cb, opaque);
if (task == NULL) {
error_report("iSCSI: failed to send inquiry command.");
itask->status = 1;
itask->complete = 1;
return;
}
}
static int parse_chap(struct iscsi_context *iscsi, const char *target)
{
QemuOptsList *list;
QemuOpts *opts;
const char *user = NULL;
const char *password = NULL;
list = qemu_find_opts("iscsi");
if (!list) {
return 0;
}
opts = qemu_opts_find(list, target);
if (opts == NULL) {
opts = QTAILQ_FIRST(&list->head);
if (!opts) {
return 0;
}
}
user = qemu_opt_get(opts, "user");
if (!user) {
return 0;
}
password = qemu_opt_get(opts, "password");
if (!password) {
error_report("CHAP username specified but no password was given");
return -1;
}
if (iscsi_set_initiator_username_pwd(iscsi, user, password)) {
error_report("Failed to set initiator username and password");
return -1;
}
return 0;
}
static void parse_header_digest(struct iscsi_context *iscsi, const char *target)
{
QemuOptsList *list;
QemuOpts *opts;
const char *digest = NULL;
list = qemu_find_opts("iscsi");
if (!list) {
return;
}
opts = qemu_opts_find(list, target);
if (opts == NULL) {
opts = QTAILQ_FIRST(&list->head);
if (!opts) {
return;
}
}
digest = qemu_opt_get(opts, "header-digest");
if (!digest) {
return;
}
if (!strcmp(digest, "CRC32C")) {
iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C);
} else if (!strcmp(digest, "NONE")) {
iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE);
} else if (!strcmp(digest, "CRC32C-NONE")) {
iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C_NONE);
} else if (!strcmp(digest, "NONE-CRC32C")) {
iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
} else {
error_report("Invalid header-digest setting : %s", digest);
}
}
static char *parse_initiator_name(const char *target)
{
QemuOptsList *list;
QemuOpts *opts;
const char *name = NULL;
const char *iscsi_name = qemu_get_vm_name();
list = qemu_find_opts("iscsi");
if (list) {
opts = qemu_opts_find(list, target);
if (!opts) {
opts = QTAILQ_FIRST(&list->head);
}
if (opts) {
name = qemu_opt_get(opts, "initiator-name");
}
}
if (name) {
return g_strdup(name);
} else {
return g_strdup_printf("iqn.2008-11.org.linux-kvm%s%s",
iscsi_name ? ":" : "",
iscsi_name ? iscsi_name : "");
}
}
/*
* We support iscsi url's on the form
* iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>
*/
static int iscsi_open(BlockDriverState *bs, const char *filename, int flags)
{
IscsiLun *iscsilun = bs->opaque;
struct iscsi_context *iscsi = NULL;
struct iscsi_url *iscsi_url = NULL;
struct IscsiTask task;
char *initiator_name = NULL;
int ret;
if ((BDRV_SECTOR_SIZE % 512) != 0) {
error_report("iSCSI: Invalid BDRV_SECTOR_SIZE. "
"BDRV_SECTOR_SIZE(%lld) is not a multiple "
"of 512", BDRV_SECTOR_SIZE);
return -EINVAL;
}
iscsi_url = iscsi_parse_full_url(iscsi, filename);
if (iscsi_url == NULL) {
error_report("Failed to parse URL : %s %s", filename,
iscsi_get_error(iscsi));
ret = -EINVAL;
goto out;
}
memset(iscsilun, 0, sizeof(IscsiLun));
initiator_name = parse_initiator_name(iscsi_url->target);
iscsi = iscsi_create_context(initiator_name);
if (iscsi == NULL) {
error_report("iSCSI: Failed to create iSCSI context.");
ret = -ENOMEM;
goto out;
}
if (iscsi_set_targetname(iscsi, iscsi_url->target)) {
error_report("iSCSI: Failed to set target name.");
ret = -EINVAL;
goto out;
}
if (iscsi_url->user != NULL) {
ret = iscsi_set_initiator_username_pwd(iscsi, iscsi_url->user,
iscsi_url->passwd);
if (ret != 0) {
error_report("Failed to set initiator username and password");
ret = -EINVAL;
goto out;
}
}
/* check if we got CHAP username/password via the options */
if (parse_chap(iscsi, iscsi_url->target) != 0) {
error_report("iSCSI: Failed to set CHAP user/password");
ret = -EINVAL;
goto out;
}
if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) != 0) {
error_report("iSCSI: Failed to set session type to normal.");
ret = -EINVAL;
goto out;
}
iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
/* check if we got HEADER_DIGEST via the options */
parse_header_digest(iscsi, iscsi_url->target);
task.iscsilun = iscsilun;
task.status = 0;
task.complete = 0;
task.bs = bs;
iscsilun->iscsi = iscsi;
iscsilun->lun = iscsi_url->lun;
if (iscsi_full_connect_async(iscsi, iscsi_url->portal, iscsi_url->lun,
iscsi_connect_cb, &task)
!= 0) {
error_report("iSCSI: Failed to start async connect.");
ret = -EINVAL;
goto out;
}
while (!task.complete) {
iscsi_set_events(iscsilun);
qemu_aio_wait();
}
if (task.status != 0) {
error_report("iSCSI: Failed to connect to LUN : %s",
iscsi_get_error(iscsi));
ret = -EINVAL;
goto out;
}
/* Medium changer or tape. We dont have any emulation for this so this must
* be sg ioctl compatible. We force it to be sg, otherwise qemu will try
* to read from the device to guess the image format.
*/
if (iscsilun->type == TYPE_MEDIUM_CHANGER ||
iscsilun->type == TYPE_TAPE) {
bs->sg = 1;
}
ret = 0;
out:
if (initiator_name != NULL) {
g_free(initiator_name);
}
if (iscsi_url != NULL) {
iscsi_destroy_url(iscsi_url);
}
if (ret) {
if (iscsi != NULL) {
iscsi_destroy_context(iscsi);
}
memset(iscsilun, 0, sizeof(IscsiLun));
}
return ret;
}
static void iscsi_close(BlockDriverState *bs)
{
IscsiLun *iscsilun = bs->opaque;
struct iscsi_context *iscsi = iscsilun->iscsi;
qemu_aio_set_fd_handler(iscsi_get_fd(iscsi), NULL, NULL, NULL, NULL);
iscsi_destroy_context(iscsi);
memset(iscsilun, 0, sizeof(IscsiLun));
}
static BlockDriver bdrv_iscsi = {
.format_name = "iscsi",
.protocol_name = "iscsi",
.instance_size = sizeof(IscsiLun),
.bdrv_file_open = iscsi_open,
.bdrv_close = iscsi_close,
.bdrv_getlength = iscsi_getlength,
.bdrv_aio_readv = iscsi_aio_readv,
.bdrv_aio_writev = iscsi_aio_writev,
.bdrv_aio_flush = iscsi_aio_flush,
.bdrv_aio_discard = iscsi_aio_discard,
#ifdef __linux__
.bdrv_ioctl = iscsi_ioctl,
.bdrv_aio_ioctl = iscsi_aio_ioctl,
#endif
};
static void iscsi_block_init(void)
{
bdrv_register(&bdrv_iscsi);
}
block_init(iscsi_block_init);