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file-win32: Switch to byte-based callbacks

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We are gradually moving away from sector-based interfaces, towards
byte-based.  Make the change for the last few sector-based callbacks
in the file-win32 driver.

Note that the driver was already using byte-based calls for
performing actual I/O, so this just gets rid of a round trip
of scaling; however, as I don't know if Windows is tolerant of
non-sector AIO operations, I went with the conservative approach
of modifying .bdrv_refresh_limits to override the block layer
defaults back to the pre-patch value of 512.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Eric Blake 2018-04-24 14:25:02 -05:00 committed by Kevin Wolf
parent e31f6864a6
commit de7056a3f9
3 changed files with 32 additions and 22 deletions
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47
block/file-win32.c
View File

@ -251,7 +251,11 @@ static void raw_probe_alignment(BlockDriverState *bs, Error **errp)
&dg.Geometry.BytesPerSector,
&freeClusters, &totalClusters);
bs->bl.request_alignment = dg.Geometry.BytesPerSector;
return;
}
/* XXX Does Windows support AIO on less than 512-byte alignment? */
bs->bl.request_alignment = 512;
}
static void raw_parse_flags(int flags, bool use_aio, int *access_flags,
@ -410,32 +414,32 @@ fail:
return ret;
}
static BlockAIOCB *raw_aio_readv(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockCompletionFunc *cb, void *opaque)
static BlockAIOCB *raw_aio_preadv(BlockDriverState *bs,
uint64_t offset, uint64_t bytes,
QEMUIOVector *qiov, int flags,
BlockCompletionFunc *cb, void *opaque)
{
BDRVRawState *s = bs->opaque;
if (s->aio) {
return win32_aio_submit(bs, s->aio, s->hfile, sector_num, qiov,
nb_sectors, cb, opaque, QEMU_AIO_READ);
return win32_aio_submit(bs, s->aio, s->hfile, offset, bytes, qiov,
cb, opaque, QEMU_AIO_READ);
} else {
return paio_submit(bs, s->hfile, sector_num << BDRV_SECTOR_BITS, qiov,
nb_sectors << BDRV_SECTOR_BITS,
return paio_submit(bs, s->hfile, offset, qiov, bytes,
cb, opaque, QEMU_AIO_READ);
}
}
static BlockAIOCB *raw_aio_writev(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockCompletionFunc *cb, void *opaque)
static BlockAIOCB *raw_aio_pwritev(BlockDriverState *bs,
uint64_t offset, uint64_t bytes,
QEMUIOVector *qiov, int flags,
BlockCompletionFunc *cb, void *opaque)
{
BDRVRawState *s = bs->opaque;
if (s->aio) {
return win32_aio_submit(bs, s->aio, s->hfile, sector_num, qiov,
nb_sectors, cb, opaque, QEMU_AIO_WRITE);
return win32_aio_submit(bs, s->aio, s->hfile, offset, bytes, qiov,
cb, opaque, QEMU_AIO_WRITE);
} else {
return paio_submit(bs, s->hfile, sector_num << BDRV_SECTOR_BITS, qiov,
nb_sectors << BDRV_SECTOR_BITS,
return paio_submit(bs, s->hfile, offset, qiov, bytes,
cb, opaque, QEMU_AIO_WRITE);
}
}
@ -632,8 +636,8 @@ BlockDriver bdrv_file = {
.bdrv_co_create_opts = raw_co_create_opts,
.bdrv_has_zero_init = bdrv_has_zero_init_1,
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
.bdrv_aio_preadv = raw_aio_preadv,
.bdrv_aio_pwritev = raw_aio_pwritev,
.bdrv_aio_flush = raw_aio_flush,
.bdrv_truncate = raw_truncate,
@ -708,6 +712,12 @@ static void hdev_parse_filename(const char *filename, QDict *options,
bdrv_parse_filename_strip_prefix(filename, "host_device:", options);
}
static void hdev_refresh_limits(BlockDriverState *bs, Error **errp)
{
/* XXX Does Windows support AIO on less than 512-byte alignment? */
bs->bl.request_alignment = 512;
}
static int hdev_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp)
{
@ -793,9 +803,10 @@ static BlockDriver bdrv_host_device = {
.bdrv_probe_device = hdev_probe_device,
.bdrv_file_open = hdev_open,
.bdrv_close = raw_close,
.bdrv_refresh_limits = hdev_refresh_limits,
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
.bdrv_aio_preadv = raw_aio_preadv,
.bdrv_aio_pwritev = raw_aio_pwritev,
.bdrv_aio_flush = raw_aio_flush,
.bdrv_detach_aio_context = raw_detach_aio_context,

5
block/win32-aio.c
View File

@ -112,15 +112,14 @@ static const AIOCBInfo win32_aiocb_info = {
BlockAIOCB *win32_aio_submit(BlockDriverState *bs,
QEMUWin32AIOState *aio, HANDLE hfile,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
uint64_t offset, uint64_t bytes, QEMUIOVector *qiov,
BlockCompletionFunc *cb, void *opaque, int type)
{
struct QEMUWin32AIOCB *waiocb;
uint64_t offset = sector_num * 512;
DWORD rc;
waiocb = qemu_aio_get(&win32_aiocb_info, bs, cb, opaque);
waiocb->nbytes = nb_sectors * 512;
waiocb->nbytes = bytes;
waiocb->qiov = qiov;
waiocb->is_read = (type == QEMU_AIO_READ);

2
include/block/raw-aio.h
View File

@ -57,7 +57,7 @@ void win32_aio_cleanup(QEMUWin32AIOState *aio);
int win32_aio_attach(QEMUWin32AIOState *aio, HANDLE hfile);
BlockAIOCB *win32_aio_submit(BlockDriverState *bs,
QEMUWin32AIOState *aio, HANDLE hfile,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
uint64_t offset, uint64_t bytes, QEMUIOVector *qiov,
BlockCompletionFunc *cb, void *opaque, int type);
void win32_aio_detach_aio_context(QEMUWin32AIOState *aio,
AioContext *old_context);