Vectored block device API (Avi Kivity)
Most devices that are capable of DMA are also capable of scatter-gather.
With the memory mapping API, this means that the device code needs to be
able to access discontiguous host memory regions.
For block devices, this translates to vectored I/O. This patch implements
an aynchronous vectored interface for the qemu block devices. At the moment
all I/O is bounced and submitted through the non-vectored API; in the future
we will convert block devices to natively support vectored I/O wherever
possible.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6397 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/block.h b/block.h
index c3314a1..9733409 100644
--- a/block.h
+++ b/block.h
@@ -2,6 +2,7 @@
#define BLOCK_H
#include "qemu-aio.h"
+#include "qemu-common.h"
/* block.c */
typedef struct BlockDriver BlockDriver;
@@ -85,6 +86,13 @@
typedef struct BlockDriverAIOCB BlockDriverAIOCB;
typedef void BlockDriverCompletionFunc(void *opaque, int ret);
+BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
+ QEMUIOVector *iov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque);
+BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
+ QEMUIOVector *iov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque);
+
BlockDriverAIOCB *bdrv_aio_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
