===================================================================
@@ -54,6 +54,8 @@ static BlockDriverAIOCB *bdrv_aio_readv_
static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
+static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs,
+ BlockDriverCompletionFunc *cb, void *opaque);
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors);
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
@@ -138,6 +140,10 @@ void bdrv_register(BlockDriver *bdrv)
bdrv->bdrv_read = bdrv_read_em;
bdrv->bdrv_write = bdrv_write_em;
}
+
+ if (!bdrv->bdrv_aio_flush)
+ bdrv->bdrv_aio_flush = bdrv_aio_flush_em;
+
bdrv->next = first_drv;
first_drv = bdrv;
}
@@ -1369,6 +1375,21 @@ BlockDriverAIOCB *bdrv_aio_writev(BlockD
return ret;
}
+BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ BlockDriver *drv = bs->drv;
+
+ if (!drv)
+ return NULL;
+
+ /*
+ * Note that unlike bdrv_flush the driver is reponsible for flushing a
+ * backing image if it exists.
+ */
+ return drv->bdrv_aio_flush(bs, cb, opaque);
+}
+
void bdrv_aio_cancel(BlockDriverAIOCB *acb)
{
acb->pool->cancel(acb);
@@ -1459,6 +1480,25 @@ static BlockDriverAIOCB *bdrv_aio_writev
return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
}
+static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ BlockDriverAIOCBSync *acb;
+
+ acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
+ acb->is_write = 1; /* don't bounce in the completion hadler */
+ acb->qiov = NULL;
+ acb->bounce = NULL;
+ acb->ret = 0;
+
+ if (!acb->bh)
+ acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
+
+ bdrv_flush(bs);
+ qemu_bh_schedule(acb->bh);
+ return &acb->common;
+}
+
/**************************************************************/
/* sync block device emulation */
===================================================================
@@ -85,6 +85,8 @@ BlockDriverAIOCB *bdrv_aio_readv(BlockDr
BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
QEMUIOVector *iov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
+BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
+ BlockDriverCompletionFunc *cb, void *opaque);
void bdrv_aio_cancel(BlockDriverAIOCB *acb);
/* sg packet commands */
===================================================================
@@ -69,6 +69,8 @@ struct BlockDriver {
BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
+ BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
+ BlockDriverCompletionFunc *cb, void *opaque);
const char *protocol_name;
int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
===================================================================
@@ -771,6 +771,16 @@ static void ide_atapi_cmd_check_status(I
ide_set_irq(s);
}
+static void ide_flush_cb(void *opaque, int ret)
+{
+ IDEState *s = opaque;
+
+ /* XXX: how do we signal I/O errors here? */
+
+ s->status = READY_STAT | SEEK_STAT;
+ ide_set_irq(s);
+}
+
static inline void cpu_to_ube16(uint8_t *buf, int val)
{
buf[0] = val >> 8;
@@ -1969,9 +1979,9 @@ void ide_ioport_write(void *opaque, uint
case WIN_FLUSH_CACHE:
case WIN_FLUSH_CACHE_EXT:
if (s->bs)
- bdrv_flush(s->bs);
- s->status = READY_STAT | SEEK_STAT;
- ide_set_irq(s);
+ bdrv_aio_flush(s->bs, ide_flush_cb, s);
+ else
+ ide_flush_cb(s, 0);
break;
case WIN_STANDBY:
case WIN_STANDBY2:
===================================================================
@@ -17,8 +17,9 @@
#define QEMU_AIO_READ 0x0001
#define QEMU_AIO_WRITE 0x0002
#define QEMU_AIO_IOCTL 0x0004
+#define QEMU_AIO_FLUSH 0x0008
#define QEMU_AIO_TYPE_MASK \
- (QEMU_AIO_READ|QEMU_AIO_WRITE|QEMU_AIO_IOCTL)
+ (QEMU_AIO_READ|QEMU_AIO_WRITE|QEMU_AIO_IOCTL|QEMU_AIO_FLUSH)
/* AIO flags */
#define QEMU_AIO_MISALIGNED 0x1000
===================================================================
@@ -574,6 +574,18 @@ static BlockDriverAIOCB *raw_aio_writev(
cb, opaque, QEMU_AIO_WRITE);
}
+static BlockDriverAIOCB *raw_aio_flush(BlockDriverState *bs,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ BDRVRawState *s = bs->opaque;
+
+ if (fd_open(bs) < 0)
+ return NULL;
+
+ return paio_submit(bs, s->aio_ctx, s->fd, 0, NULL, 0,
+ cb, opaque, QEMU_AIO_FLUSH);
+}
+
static void raw_close(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
@@ -749,6 +761,7 @@ static BlockDriver bdrv_raw = {
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
+ .bdrv_aio_flush = raw_aio_flush,
.bdrv_truncate = raw_truncate,
.bdrv_getlength = raw_getlength,
@@ -1002,6 +1015,7 @@ static BlockDriver bdrv_host_device = {
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
+ .bdrv_aio_flush = raw_aio_flush,
.bdrv_read = raw_read,
.bdrv_write = raw_write,
@@ -1096,6 +1110,7 @@ static BlockDriver bdrv_host_floppy = {
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
+ .bdrv_aio_flush = raw_aio_flush,
.bdrv_read = raw_read,
.bdrv_write = raw_write,
@@ -1176,6 +1191,7 @@ static BlockDriver bdrv_host_cdrom = {
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
+ .bdrv_aio_flush = raw_aio_flush,
.bdrv_read = raw_read,
.bdrv_write = raw_write,
@@ -1295,6 +1311,7 @@ static BlockDriver bdrv_host_cdrom = {
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
+ .bdrv_aio_flush = raw_aio_flush,
.bdrv_read = raw_read,
.bdrv_write = raw_write,
===================================================================
@@ -134,6 +134,16 @@ static size_t handle_aiocb_ioctl(struct
return aiocb->aio_nbytes;
}
+static size_t handle_aiocb_flush(struct qemu_paiocb *aiocb)
+{
+ int ret;
+
+ ret = fdatasync(aiocb->aio_fildes);
+ if (ret == -1)
+ return -errno;
+ return 0;
+}
+
#ifdef CONFIG_PREADV
static ssize_t
@@ -330,6 +340,9 @@ static void *aio_thread(void *unused)
case QEMU_AIO_WRITE:
ret = handle_aiocb_rw(aiocb);
break;
+ case QEMU_AIO_FLUSH:
+ ret = handle_aiocb_flush(aiocb);
+ break;
case QEMU_AIO_IOCTL:
ret = handle_aiocb_ioctl(aiocb);
break;
@@ -530,8 +543,10 @@ BlockDriverAIOCB *paio_submit(BlockDrive
acb->aio_type = type;
acb->aio_fildes = fd;
acb->ev_signo = SIGUSR2;
- acb->aio_iov = qiov->iov;
- acb->aio_niov = qiov->niov;
+ if (qiov) {
+ acb->aio_iov = qiov->iov;
+ acb->aio_niov = qiov->niov;
+ }
acb->aio_nbytes = nb_sectors * 512;
acb->aio_offset = sector_num * 512;
Instead stalling the VCPU while serving a cache flush try to do it asynchronously. Use our good old helper thread pool to issue an asynchronous fdatasync for raw-posix. Note that while Linux AIO implements a fdatasync operation it is not useful for us because it isn't actually implement in asynchronous fashion. For now only use it in IDE because virtio-blk doesn't implement cache flusing yet (will be fixed in patch 4/4) and the interface between the HBA emulation and scsi-disk will need some changes to accomodate it for scsi (will be a separate patch series). Signed-off-by: Christoph Hellwig <hch@lst.de>