block/iscsi: introduce bdrv_co_{readv, writev, flush_to_disk}
this converts read, write and flush functions from aio to coroutines
eliminating almost 200 lines of code.
The requirement for libiscsi is bumped to version 1.4.0 which was
released in may 2012.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/block/iscsi.c b/block/iscsi.c
index 829d444..fa69408 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -239,44 +239,6 @@
iscsi_set_events(iscsilun);
}
-static int
-iscsi_aio_writev_acb(IscsiAIOCB *acb);
-
-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);
- acb->buf = NULL;
-
- if (acb->canceled != 0) {
- return;
- }
-
- acb->status = 0;
- if (status != 0) {
- if (status == SCSI_STATUS_CHECK_CONDITION
- && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION
- && acb->retries-- > 0) {
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
- if (iscsi_aio_writev_acb(acb) == 0) {
- iscsi_set_events(acb->iscsilun);
- return;
- }
- }
- 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_lun2qemu(int64_t sector, IscsiLun *iscsilun)
{
return sector * iscsilun->block_size / BDRV_SECTOR_SIZE;
@@ -301,324 +263,172 @@
return 1;
}
-static int
-iscsi_aio_writev_acb(IscsiAIOCB *acb)
+static int coroutine_fn iscsi_co_writev(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors,
+ QEMUIOVector *iov)
{
- struct iscsi_context *iscsi = acb->iscsilun->iscsi;
- size_t size;
- uint32_t num_sectors;
+ IscsiLun *iscsilun = bs->opaque;
+ struct IscsiTask iTask;
uint64_t lba;
+ uint32_t num_sectors;
+ uint8_t *data = NULL;
+ uint8_t *buf = NULL;
+
+ if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
+ return -EINVAL;
+ }
+
+ lba = sector_qemu2lun(sector_num, iscsilun);
+ num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
#if !defined(LIBISCSI_FEATURE_IOVECTOR)
- struct iscsi_data data;
-#endif
- int ret;
-
- acb->canceled = 0;
- acb->bh = NULL;
- acb->status = -EINPROGRESS;
- acb->buf = NULL;
-
- /* this will allow us to get rid of 'buf' completely */
- size = acb->nb_sectors * BDRV_SECTOR_SIZE;
-
-#if !defined(LIBISCSI_FEATURE_IOVECTOR)
- data.size = MIN(size, acb->qiov->size);
-
/* if the iovec only contains one buffer we can pass it directly */
- if (acb->qiov->niov == 1) {
- data.data = acb->qiov->iov[0].iov_base;
+ if (iov->niov == 1) {
+ data = iov->iov[0].iov_base;
} else {
- acb->buf = g_malloc(data.size);
- qemu_iovec_to_buf(acb->qiov, 0, acb->buf, data.size);
- data.data = acb->buf;
+ size_t size = MIN(nb_sectors * BDRV_SECTOR_SIZE, iov->size);
+ buf = g_malloc(size);
+ qemu_iovec_to_buf(iov, 0, buf, size);
+ data = buf;
}
#endif
-
- 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));
- return -1;
+ iscsi_co_init_iscsitask(iscsilun, &iTask);
+retry:
+ iTask.task = iscsi_write16_task(iscsilun->iscsi, iscsilun->lun, lba,
+ data, num_sectors * iscsilun->block_size,
+ iscsilun->block_size, 0, 0, 0, 0, 0,
+ iscsi_co_generic_cb, &iTask);
+ if (iTask.task == NULL) {
+ g_free(buf);
+ return -EIO;
}
- 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(acb->sector_num, acb->iscsilun);
- *(uint32_t *)&acb->task->cdb[2] = htonl(lba >> 32);
- *(uint32_t *)&acb->task->cdb[6] = htonl(lba & 0xffffffff);
- num_sectors = sector_qemu2lun(acb->nb_sectors, acb->iscsilun);
- *(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors);
- acb->task->expxferlen = size;
-
#if defined(LIBISCSI_FEATURE_IOVECTOR)
- ret = iscsi_scsi_command_async(iscsi, acb->iscsilun->lun, acb->task,
- iscsi_aio_write16_cb,
- NULL,
- acb);
-#else
- ret = iscsi_scsi_command_async(iscsi, acb->iscsilun->lun, acb->task,
- iscsi_aio_write16_cb,
- &data,
- acb);
+ scsi_task_set_iov_out(iTask.task, (struct scsi_iovec *) iov->iov,
+ iov->niov);
#endif
- if (ret != 0) {
- scsi_free_scsi_task(acb->task);
- g_free(acb->buf);
- return -1;
+ while (!iTask.complete) {
+ iscsi_set_events(iscsilun);
+ qemu_coroutine_yield();
}
-#if defined(LIBISCSI_FEATURE_IOVECTOR)
- scsi_task_set_iov_out(acb->task, (struct scsi_iovec*) acb->qiov->iov, acb->qiov->niov);
-#endif
+ if (iTask.task != NULL) {
+ scsi_free_scsi_task(iTask.task);
+ iTask.task = NULL;
+ }
+
+ if (iTask.do_retry) {
+ goto retry;
+ }
+
+ g_free(buf);
+
+ if (iTask.status != SCSI_STATUS_GOOD) {
+ return -EIO;
+ }
return 0;
}
-static BlockDriverAIOCB *
-iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num,
- QEMUIOVector *qiov, int nb_sectors,
- BlockDriverCompletionFunc *cb,
- void *opaque)
+static int coroutine_fn iscsi_co_readv(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors,
+ QEMUIOVector *iov)
{
IscsiLun *iscsilun = bs->opaque;
- IscsiAIOCB *acb;
-
- if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
- return NULL;
- }
-
- acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
- trace_iscsi_aio_writev(iscsilun->iscsi, sector_num, nb_sectors, opaque, acb);
-
- acb->iscsilun = iscsilun;
- acb->qiov = qiov;
- acb->nb_sectors = nb_sectors;
- acb->sector_num = sector_num;
- acb->retries = ISCSI_CMD_RETRIES;
-
- if (iscsi_aio_writev_acb(acb) != 0) {
- qemu_aio_release(acb);
- return NULL;
- }
-
- iscsi_set_events(iscsilun);
- return &acb->common;
-}
-
-static int
-iscsi_aio_readv_acb(IscsiAIOCB *acb);
-
-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) {
- if (status == SCSI_STATUS_CHECK_CONDITION
- && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION
- && acb->retries-- > 0) {
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
- if (iscsi_aio_readv_acb(acb) == 0) {
- iscsi_set_events(acb->iscsilun);
- return;
- }
- }
- error_report("Failed to read16 data from iSCSI lun. %s",
- iscsi_get_error(iscsi));
- acb->status = -EIO;
- }
-
- iscsi_schedule_bh(acb);
-}
-
-static int
-iscsi_aio_readv_acb(IscsiAIOCB *acb)
-{
- struct iscsi_context *iscsi = acb->iscsilun->iscsi;
- size_t size;
+ struct IscsiTask iTask;
uint64_t lba;
uint32_t num_sectors;
- int ret;
#if !defined(LIBISCSI_FEATURE_IOVECTOR)
int i;
#endif
- acb->canceled = 0;
- acb->bh = NULL;
- acb->status = -EINPROGRESS;
- acb->buf = NULL;
-
- size = acb->nb_sectors * BDRV_SECTOR_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));
- return -1;
+ if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
+ return -EINVAL;
}
- memset(acb->task, 0, sizeof(struct scsi_task));
- acb->task->xfer_dir = SCSI_XFER_READ;
- acb->task->expxferlen = size;
- lba = sector_qemu2lun(acb->sector_num, acb->iscsilun);
- num_sectors = sector_qemu2lun(acb->nb_sectors, acb->iscsilun);
+ lba = sector_qemu2lun(sector_num, iscsilun);
+ num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
- switch (acb->iscsilun->type) {
+ iscsi_co_init_iscsitask(iscsilun, &iTask);
+retry:
+ 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);
+ iTask.task = iscsi_read16_task(iscsilun->iscsi, iscsilun->lun, lba,
+ num_sectors * iscsilun->block_size,
+ iscsilun->block_size, 0, 0, 0, 0, 0,
+ iscsi_co_generic_cb, &iTask);
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);
+ iTask.task = iscsi_read10_task(iscsilun->iscsi, iscsilun->lun, lba,
+ num_sectors * iscsilun->block_size,
+ iscsilun->block_size, 0, 0, 0, 0, 0,
+ iscsi_co_generic_cb, &iTask);
break;
}
-
- ret = iscsi_scsi_command_async(iscsi, acb->iscsilun->lun, acb->task,
- iscsi_aio_read16_cb,
- NULL,
- acb);
- if (ret != 0) {
- scsi_free_scsi_task(acb->task);
- return -1;
+ if (iTask.task == NULL) {
+ return -EIO;
}
-
#if defined(LIBISCSI_FEATURE_IOVECTOR)
- scsi_task_set_iov_in(acb->task, (struct scsi_iovec*) acb->qiov->iov, acb->qiov->niov);
+ scsi_task_set_iov_in(iTask.task, (struct scsi_iovec *) iov->iov, iov->niov);
#else
- 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);
+ for (i = 0; i < iov->niov; i++) {
+ scsi_task_add_data_in_buffer(iTask.task,
+ iov->iov[i].iov_len,
+ iov->iov[i].iov_base);
}
#endif
- return 0;
-}
-static BlockDriverAIOCB *
-iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num,
- QEMUIOVector *qiov, int nb_sectors,
- BlockDriverCompletionFunc *cb,
- void *opaque)
-{
- IscsiLun *iscsilun = bs->opaque;
- IscsiAIOCB *acb;
-
- if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
- return NULL;
+ while (!iTask.complete) {
+ iscsi_set_events(iscsilun);
+ qemu_coroutine_yield();
}
- acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
- trace_iscsi_aio_readv(iscsilun->iscsi, sector_num, nb_sectors, opaque, acb);
-
- acb->nb_sectors = nb_sectors;
- acb->sector_num = sector_num;
- acb->iscsilun = iscsilun;
- acb->qiov = qiov;
- acb->retries = ISCSI_CMD_RETRIES;
-
- if (iscsi_aio_readv_acb(acb) != 0) {
- qemu_aio_release(acb);
- return NULL;
+ if (iTask.task != NULL) {
+ scsi_free_scsi_task(iTask.task);
+ iTask.task = NULL;
}
- iscsi_set_events(iscsilun);
- return &acb->common;
-}
-
-static int
-iscsi_aio_flush_acb(IscsiAIOCB *acb);
-
-static void
-iscsi_synccache10_cb(struct iscsi_context *iscsi, int status,
- void *command_data, void *opaque)
-{
- IscsiAIOCB *acb = opaque;
-
- if (acb->canceled != 0) {
- return;
+ if (iTask.do_retry) {
+ goto retry;
}
- acb->status = 0;
- if (status != 0) {
- if (status == SCSI_STATUS_CHECK_CONDITION
- && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION
- && acb->retries-- > 0) {
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
- if (iscsi_aio_flush_acb(acb) == 0) {
- iscsi_set_events(acb->iscsilun);
- return;
- }
- }
- error_report("Failed to sync10 data on iSCSI lun. %s",
- iscsi_get_error(iscsi));
- acb->status = -EIO;
- }
-
- iscsi_schedule_bh(acb);
-}
-
-static int
-iscsi_aio_flush_acb(IscsiAIOCB *acb)
-{
- struct iscsi_context *iscsi = acb->iscsilun->iscsi;
-
- acb->canceled = 0;
- acb->bh = NULL;
- acb->status = -EINPROGRESS;
- acb->buf = NULL;
-
- acb->task = iscsi_synchronizecache10_task(iscsi, acb->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));
- return -1;
+ if (iTask.status != SCSI_STATUS_GOOD) {
+ return -EIO;
}
return 0;
}
-static BlockDriverAIOCB *
-iscsi_aio_flush(BlockDriverState *bs,
- BlockDriverCompletionFunc *cb, void *opaque)
+static int coroutine_fn iscsi_co_flush(BlockDriverState *bs)
{
IscsiLun *iscsilun = bs->opaque;
+ struct IscsiTask iTask;
- IscsiAIOCB *acb;
+ iscsi_co_init_iscsitask(iscsilun, &iTask);
- acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
-
- acb->iscsilun = iscsilun;
- acb->retries = ISCSI_CMD_RETRIES;
-
- if (iscsi_aio_flush_acb(acb) != 0) {
- qemu_aio_release(acb);
- return NULL;
+retry:
+ if (iscsi_synchronizecache10_task(iscsilun->iscsi, iscsilun->lun, 0, 0, 0,
+ 0, iscsi_co_generic_cb, &iTask) == NULL) {
+ return -EIO;
}
- iscsi_set_events(iscsilun);
+ while (!iTask.complete) {
+ iscsi_set_events(iscsilun);
+ qemu_coroutine_yield();
+ }
- return &acb->common;
+ if (iTask.task != NULL) {
+ scsi_free_scsi_task(iTask.task);
+ iTask.task = NULL;
+ }
+
+ if (iTask.do_retry) {
+ goto retry;
+ }
+
+ if (iTask.status != SCSI_STATUS_GOOD) {
+ return -EIO;
+ }
+
+ return 0;
}
#ifdef __linux__
@@ -1624,10 +1434,9 @@
#if defined(SCSI_SENSE_ASCQ_CAPACITY_DATA_HAS_CHANGED)
.bdrv_co_write_zeroes = iscsi_co_write_zeroes,
#endif
-
- .bdrv_aio_readv = iscsi_aio_readv,
- .bdrv_aio_writev = iscsi_aio_writev,
- .bdrv_aio_flush = iscsi_aio_flush,
+ .bdrv_co_readv = iscsi_co_readv,
+ .bdrv_co_writev = iscsi_co_writev,
+ .bdrv_co_flush_to_disk = iscsi_co_flush,
#ifdef __linux__
.bdrv_ioctl = iscsi_ioctl,
diff --git a/configure b/configure
index 0666228..8144d9f 100755
--- a/configure
+++ b/configure
@@ -3025,13 +3025,13 @@
##########################################
# Do we have libiscsi
-# We check for iscsi_unmap_sync() to make sure we have a
-# recent enough version of libiscsi.
+# We check for iscsi_write16_sync() to make sure we have a
+# at least version 1.4.0 of libiscsi.
if test "$libiscsi" != "no" ; then
cat > $TMPC << EOF
#include <stdio.h>
#include <iscsi/iscsi.h>
-int main(void) { iscsi_unmap_sync(NULL,0,0,0,NULL,0); return 0; }
+int main(void) { iscsi_write16_sync(NULL,0,0,NULL,0,0,0,0,0,0,0); return 0; }
EOF
if $pkg_config --atleast-version=1.7.0 libiscsi; then
libiscsi="yes"
