From: Eric Blake <ebl...@redhat.com>
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 <ebl...@redhat.com>
Signed-off-by: Kevin Wolf <kw...@redhat.com>
---
block/iscsi.c | 58 ++++++++++++++++++++++++++++++++++------------------------
1 file changed, 34 insertions(+), 24 deletions(-)
diff --git a/block/iscsi.c b/block/iscsi.c
index 52ea9d7..7e78ade 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -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;
- }
- return 1;
+ 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 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,
--
1.8.3.1
