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iscsi: Convert to bdrv_co_pwrite_zeroes()

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Another step on our continuing quest to switch to byte-based
interfaces.

As this is the first byte-based iscsi interface, convert
is_request_lun_aligned() into two versions, one for sectors
and one for bytes.  Also, change from outright -EINVAL failure
on an unaligned request, to instead failing with -ENOTSUP to
trigger a read-modify-write fallback, particularly since the
block layer should be honoring bs->request_alignment to avoid
-EINVAL on read/write requests.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Eric Blake 2016-06-01 15:10:05 -06:00 committed by Kevin Wolf
parent 74021bc497
commit 94d047a35b
1 changed files with 33 additions and 23 deletions
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56
block/iscsi.c
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@ -401,18 +401,26 @@ static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
}
static bool is_request_lun_aligned(int64_t sector_num, int nb_sectors,
IscsiLun *iscsilun)
static bool is_byte_request_lun_aligned(int64_t offset, int count,
IscsiLun *iscsilun)
{
if ((sector_num * BDRV_SECTOR_SIZE) % iscsilun->block_size ||
(nb_sectors * BDRV_SECTOR_SIZE) % iscsilun->block_size) {
error_report("iSCSI misaligned request: "
"iscsilun->block_size %u, sector_num %" PRIi64
", nb_sectors %d",
iscsilun->block_size, sector_num, nb_sectors);
return 0;
if (offset % iscsilun->block_size || count % iscsilun->block_size) {
error_report("iSCSI misaligned request: "
"iscsilun->block_size %u, offset %" PRIi64
", count %d",
iscsilun->block_size, offset, count);
return false;
}
return 1;
return true;
}
static bool is_sector_request_lun_aligned(int64_t sector_num, int nb_sectors,
IscsiLun *iscsilun)
{
assert(nb_sectors < BDRV_REQUEST_MAX_SECTORS);
return is_byte_request_lun_aligned(sector_num << BDRV_SECTOR_BITS,
nb_sectors << BDRV_SECTOR_BITS,
iscsilun);
}
static unsigned long *iscsi_allocationmap_init(IscsiLun *iscsilun)
@ -461,7 +469,7 @@ iscsi_co_writev_flags(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
if (fua) {
assert(iscsilun->dpofua);
}
if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
return -EINVAL;
}
@ -541,7 +549,7 @@ static int64_t coroutine_fn iscsi_co_get_block_status(BlockDriverState *bs,
iscsi_co_init_iscsitask(iscsilun, &iTask);
if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
ret = -EINVAL;
goto out;
}
@ -638,7 +646,7 @@ static int coroutine_fn iscsi_co_readv(BlockDriverState *bs,
uint64_t lba;
uint32_t num_sectors;
if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
return -EINVAL;
}
@ -926,7 +934,7 @@ coroutine_fn iscsi_co_discard(BlockDriverState *bs, int64_t sector_num,
struct IscsiTask iTask;
struct unmap_list list;
if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
return -EINVAL;
}
@ -977,8 +985,8 @@ retry:
}
static int
coroutine_fn iscsi_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, BdrvRequestFlags flags)
coroutine_fn iscsi_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
int count, BdrvRequestFlags flags)
{
IscsiLun *iscsilun = bs->opaque;
struct IscsiTask iTask;
@ -986,8 +994,8 @@ coroutine_fn iscsi_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
uint32_t nb_blocks;
bool use_16_for_ws = iscsilun->use_16_for_rw;
if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
return -EINVAL;
if (!is_byte_request_lun_aligned(offset, count, iscsilun)) {
return -ENOTSUP;
}
if (flags & BDRV_REQ_MAY_UNMAP) {
@ -1008,8 +1016,8 @@ coroutine_fn iscsi_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
return -ENOTSUP;
}
lba = sector_qemu2lun(sector_num, iscsilun);
nb_blocks = sector_qemu2lun(nb_sectors, iscsilun);
lba = offset / iscsilun->block_size;
nb_blocks = count / iscsilun->block_size;
if (iscsilun->zeroblock == NULL) {
iscsilun->zeroblock = g_try_malloc0(iscsilun->block_size);
@ -1065,9 +1073,11 @@ retry:
}
if (flags & BDRV_REQ_MAY_UNMAP) {
iscsi_allocationmap_clear(iscsilun, sector_num, nb_sectors);
iscsi_allocationmap_clear(iscsilun, offset >> BDRV_SECTOR_BITS,
count >> BDRV_SECTOR_BITS);
} else {
iscsi_allocationmap_set(iscsilun, sector_num, nb_sectors);
iscsi_allocationmap_set(iscsilun, offset >> BDRV_SECTOR_BITS,
count >> BDRV_SECTOR_BITS);
}
return 0;
@ -1856,7 +1866,7 @@ static BlockDriver bdrv_iscsi = {
.bdrv_co_get_block_status = iscsi_co_get_block_status,
.bdrv_co_discard = iscsi_co_discard,
.bdrv_co_write_zeroes = iscsi_co_write_zeroes,
.bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,
.bdrv_co_readv = iscsi_co_readv,
.bdrv_co_writev_flags = iscsi_co_writev_flags,
.bdrv_co_flush_to_disk = iscsi_co_flush,