diff options
author | Peter Lieven <pl@dlhnet.de> | 2013-02-21 16:15:54 +0100 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2013-03-05 17:51:50 +0100 |
commit | 1dde716ed6719c341c1bfa427781f0715af90cbc (patch) | |
tree | 07bee51d3b13cb1ec2ad646eacf6507e5aaca191 /block | |
parent | 76c48503c4c87afabf0c93acf78480f65276844d (diff) |
iscsi: retry read, write, flush and unmap on unit attention check conditions
the storage might return a check condition status for various reasons.
(e.g. bus reset, capacity change, thin-provisioning info etc.)
currently all these informative status responses lead to an I/O error
which is populated to the guest. this patch introduces a retry mechanism
to avoid this.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'block')
-rw-r--r-- | block/iscsi.c | 291 |
1 files changed, 203 insertions, 88 deletions
diff --git a/block/iscsi.c b/block/iscsi.c index deb3b68890..439af6f217 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -60,8 +60,11 @@ typedef struct IscsiAIOCB { uint8_t *buf; int status; int canceled; + int retries; size_t read_size; size_t read_offset; + int64_t sector_num; + int nb_sectors; #ifdef __linux__ sg_io_hdr_t *ioh; #endif @@ -69,6 +72,7 @@ typedef struct IscsiAIOCB { #define NOP_INTERVAL 5000 #define MAX_NOP_FAILURES 3 +#define ISCSI_CMD_RETRIES 5 static void iscsi_bh_cb(void *p) @@ -191,6 +195,8 @@ iscsi_process_write(void *arg) iscsi_set_events(iscsilun); } +static int +iscsi_aio_writev_acb(IscsiAIOCB *acb); static void iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status, @@ -208,7 +214,19 @@ iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status, } acb->status = 0; - if (status < 0) { + if (status != 0) { + if (status == SCSI_STATUS_CHECK_CONDITION + && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION + && acb->retries-- > 0) { + if (acb->task != NULL) { + 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; @@ -222,15 +240,10 @@ 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) +static int +iscsi_aio_writev_acb(IscsiAIOCB *acb) { - IscsiLun *iscsilun = bs->opaque; - struct iscsi_context *iscsi = iscsilun->iscsi; - IscsiAIOCB *acb; + struct iscsi_context *iscsi = acb->iscsilun->iscsi; size_t size; uint32_t num_sectors; uint64_t lba; @@ -239,19 +252,13 @@ iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num, #endif int ret; - acb = qemu_aio_get(&iscsi_aiocb_info, 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; acb->buf = NULL; /* this will allow us to get rid of 'buf' completely */ - size = nb_sectors * BDRV_SECTOR_SIZE; + size = acb->nb_sectors * BDRV_SECTOR_SIZE; #if !defined(LIBISCSI_FEATURE_IOVECTOR) data.size = MIN(size, acb->qiov->size); @@ -270,48 +277,76 @@ iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num, 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; + return -1; } 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); + 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 = size / iscsilun->block_size; + num_sectors = size / acb->iscsilun->block_size; *(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors); acb->task->expxferlen = size; #if defined(LIBISCSI_FEATURE_IOVECTOR) - ret = iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task, + ret = iscsi_scsi_command_async(iscsi, acb->iscsilun->lun, acb->task, iscsi_aio_write16_cb, NULL, acb); #else - ret = iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task, + ret = iscsi_scsi_command_async(iscsi, acb->iscsilun->lun, acb->task, iscsi_aio_write16_cb, &data, acb); #endif if (ret != 0) { - scsi_free_scsi_task(acb->task); g_free(acb->buf); - qemu_aio_release(acb); - return NULL; + return -1; } #if defined(LIBISCSI_FEATURE_IOVECTOR) scsi_task_set_iov_out(acb->task, (struct scsi_iovec*) acb->qiov->iov, acb->qiov->niov); #endif - iscsi_set_events(iscsilun); + return 0; +} + +static BlockDriverAIOCB * +iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num, + QEMUIOVector *qiov, int nb_sectors, + BlockDriverCompletionFunc *cb, + void *opaque) +{ + IscsiLun *iscsilun = bs->opaque; + IscsiAIOCB *acb; + + 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) { + if (acb->task) { + scsi_free_scsi_task(acb->task); + } + 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) @@ -326,6 +361,18 @@ iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status, acb->status = 0; if (status != 0) { + if (status == SCSI_STATUS_CHECK_CONDITION + && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION + && acb->retries-- > 0) { + if (acb->task != NULL) { + 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; @@ -334,35 +381,20 @@ iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status, iscsi_schedule_bh(acb); } -static BlockDriverAIOCB * -iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockDriverCompletionFunc *cb, - void *opaque) +static int +iscsi_aio_readv_acb(IscsiAIOCB *acb) { - IscsiLun *iscsilun = bs->opaque; - struct iscsi_context *iscsi = iscsilun->iscsi; - IscsiAIOCB *acb; - size_t qemu_read_size; + struct iscsi_context *iscsi = acb->iscsilun->iscsi; + uint64_t lba; + uint32_t num_sectors; + int ret; #if !defined(LIBISCSI_FEATURE_IOVECTOR) int i; #endif - int ret; - uint64_t lba; - uint32_t num_sectors; - - qemu_read_size = BDRV_SECTOR_SIZE * (size_t)nb_sectors; - - acb = qemu_aio_get(&iscsi_aiocb_info, 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 @@ -370,30 +402,29 @@ iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num, * data. */ acb->read_offset = 0; - if (iscsilun->block_size > BDRV_SECTOR_SIZE) { - uint64_t bdrv_offset = BDRV_SECTOR_SIZE * sector_num; + if (acb->iscsilun->block_size > BDRV_SECTOR_SIZE) { + uint64_t bdrv_offset = BDRV_SECTOR_SIZE * acb->sector_num; - acb->read_offset = bdrv_offset % iscsilun->block_size; + acb->read_offset = bdrv_offset % acb->iscsilun->block_size; } - num_sectors = (qemu_read_size + iscsilun->block_size + num_sectors = (acb->read_size + acb->iscsilun->block_size + acb->read_offset - 1) - / iscsilun->block_size; + / acb->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; + return -1; } 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; + lba = sector_qemu2lun(acb->sector_num, acb->iscsilun); + acb->task->expxferlen = acb->read_size; - switch (iscsilun->type) { + switch (acb->iscsilun->type) { case TYPE_DISK: acb->task->cdb_size = 16; acb->task->cdb[0] = 0x88; @@ -409,14 +440,12 @@ iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num, break; } - ret = iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task, + 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); - qemu_aio_release(acb); - return NULL; + return -1; } #if defined(LIBISCSI_FEATURE_IOVECTOR) @@ -428,12 +457,42 @@ iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num, acb->qiov->iov[i].iov_base); } #endif + return 0; +} - iscsi_set_events(iscsilun); +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; + 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->read_size = BDRV_SECTOR_SIZE * (size_t)acb->nb_sectors; + acb->retries = ISCSI_CMD_RETRIES; + + if (iscsi_aio_readv_acb(acb) != 0) { + if (acb->task) { + scsi_free_scsi_task(acb->task); + } + qemu_aio_release(acb); + return 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, @@ -446,7 +505,19 @@ iscsi_synccache10_cb(struct iscsi_context *iscsi, int status, } acb->status = 0; - if (status < 0) { + if (status != 0) { + if (status == SCSI_STATUS_CHECK_CONDITION + && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION + && acb->retries-- > 0) { + if (acb->task != NULL) { + 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; @@ -455,29 +526,43 @@ iscsi_synccache10_cb(struct iscsi_context *iscsi, int status, iscsi_schedule_bh(acb); } -static BlockDriverAIOCB * -iscsi_aio_flush(BlockDriverState *bs, - BlockDriverCompletionFunc *cb, void *opaque) +static int +iscsi_aio_flush_acb(IscsiAIOCB *acb) { - IscsiLun *iscsilun = bs->opaque; - struct iscsi_context *iscsi = iscsilun->iscsi; - IscsiAIOCB *acb; - - acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque); + struct iscsi_context *iscsi = acb->iscsilun->iscsi; - acb->iscsilun = iscsilun; acb->canceled = 0; acb->bh = NULL; acb->status = -EINPROGRESS; acb->buf = NULL; - acb->task = iscsi_synchronizecache10_task(iscsi, iscsilun->lun, + 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; + } + + return 0; +} + +static BlockDriverAIOCB * +iscsi_aio_flush(BlockDriverState *bs, + BlockDriverCompletionFunc *cb, void *opaque) +{ + IscsiLun *iscsilun = bs->opaque; + + IscsiAIOCB *acb; + + 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; } @@ -487,6 +572,8 @@ iscsi_aio_flush(BlockDriverState *bs, return &acb->common; } +static int iscsi_aio_discard_acb(IscsiAIOCB *acb); + static void iscsi_unmap_cb(struct iscsi_context *iscsi, int status, void *command_data, void *opaque) @@ -498,7 +585,19 @@ iscsi_unmap_cb(struct iscsi_context *iscsi, int status, } acb->status = 0; - if (status < 0) { + if (status != 0) { + if (status == SCSI_STATUS_CHECK_CONDITION + && acb->task->sense.key == SCSI_SENSE_UNIT_ATTENTION + && acb->retries-- > 0) { + if (acb->task != NULL) { + scsi_free_scsi_task(acb->task); + acb->task = NULL; + } + if (iscsi_aio_discard_acb(acb) == 0) { + iscsi_set_events(acb->iscsilun); + return; + } + } error_report("Failed to unmap data on iSCSI lun. %s", iscsi_get_error(iscsi)); acb->status = -EIO; @@ -507,34 +606,50 @@ iscsi_unmap_cb(struct iscsi_context *iscsi, int status, 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; +static int iscsi_aio_discard_acb(IscsiAIOCB *acb) { + struct iscsi_context *iscsi = acb->iscsilun->iscsi; struct unmap_list list[1]; - acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque); - - acb->iscsilun = iscsilun; acb->canceled = 0; acb->bh = NULL; acb->status = -EINPROGRESS; acb->buf = NULL; - list[0].lba = sector_qemu2lun(sector_num, iscsilun); - list[0].num = nb_sectors * BDRV_SECTOR_SIZE / iscsilun->block_size; + list[0].lba = sector_qemu2lun(acb->sector_num, acb->iscsilun); + list[0].num = acb->nb_sectors * BDRV_SECTOR_SIZE / acb->iscsilun->block_size; - acb->task = iscsi_unmap_task(iscsi, iscsilun->lun, + acb->task = iscsi_unmap_task(iscsi, acb->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)); + return -1; + } + + return 0; +} + +static BlockDriverAIOCB * +iscsi_aio_discard(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, + BlockDriverCompletionFunc *cb, void *opaque) +{ + IscsiLun *iscsilun = bs->opaque; + IscsiAIOCB *acb; + + acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque); + + acb->iscsilun = iscsilun; + acb->nb_sectors = nb_sectors; + acb->sector_num = sector_num; + acb->retries = ISCSI_CMD_RETRIES; + + if (iscsi_aio_discard_acb(acb) != 0) { + if (acb->task) { + scsi_free_scsi_task(acb->task); + } qemu_aio_release(acb); return NULL; } |