In order to be able to call bdrv_co_readv/writev for drivers that don't
implement the functions natively, add an emulation that uses the AIO functions
to implement them.
Signed-off-by: Kevin Wolf
---
block.c | 84 -
trace-events |1 +
2 files changed, 77 insertions(+), 8 deletions(-)
diff --git a/block.c b/block.c
index 48413ae..2f589ac 100644
--- a/block.c
+++ b/block.c
@@ -64,6 +64,12 @@ static BlockDriverAIOCB
*bdrv_co_aio_readv_em(BlockDriverState *bs,
static BlockDriverAIOCB *bdrv_co_aio_writev_em(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
+static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors,
+ QEMUIOVector *iov);
+static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors,
+ QEMUIOVector *iov);
static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
QTAILQ_HEAD_INITIALIZER(bdrv_states);
@@ -182,14 +188,19 @@ void bdrv_register(BlockDriver *bdrv)
bdrv->bdrv_aio_writev = bdrv_co_aio_writev_em;
bdrv->bdrv_read = bdrv_read_em;
bdrv->bdrv_write = bdrv_write_em;
- } else if (!bdrv->bdrv_aio_readv) {
-/* add AIO emulation layer */
-bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
-bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
-} else if (!bdrv->bdrv_read) {
-/* add synchronous IO emulation layer */
-bdrv->bdrv_read = bdrv_read_em;
-bdrv->bdrv_write = bdrv_write_em;
+ } else {
+bdrv->bdrv_co_readv = bdrv_co_readv_em;
+bdrv->bdrv_co_writev = bdrv_co_writev_em;
+
+if (!bdrv->bdrv_aio_readv) {
+/* add AIO emulation layer */
+bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
+bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
+} else if (!bdrv->bdrv_read) {
+/* add synchronous IO emulation layer */
+bdrv->bdrv_read = bdrv_read_em;
+bdrv->bdrv_write = bdrv_write_em;
+}
}
if (!bdrv->bdrv_aio_flush)
@@ -2868,6 +2879,63 @@ void qemu_aio_release(void *p)
}
/**/
+/* Coroutine block device emulation */
+
+typedef struct CoroutineIOCompletion {
+Coroutine *coroutine;
+int ret;
+} CoroutineIOCompletion;
+
+static void bdrv_co_io_em_complete(void *opaque, int ret)
+{
+CoroutineIOCompletion *co = opaque;
+
+co->ret = ret;
+qemu_coroutine_enter(co->coroutine, NULL);
+}
+
+static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num,
+ int nb_sectors, QEMUIOVector *iov,
+ bool is_write)
+{
+CoroutineIOCompletion co = {
+.coroutine = qemu_coroutine_self(),
+.ret = -EINPROGRESS,
+};
+BlockDriverAIOCB *acb;
+
+if (is_write) {
+acb = bdrv_aio_writev(bs, sector_num, iov, nb_sectors,
+ bdrv_co_io_em_complete, &co);
+} else {
+acb = bdrv_aio_readv(bs, sector_num, iov, nb_sectors,
+ bdrv_co_io_em_complete, &co);
+}
+
+trace_bdrv_co_io(is_write, acb);
+if (!acb) {
+return -EIO;
+}
+qemu_coroutine_yield();
+
+return co.ret;
+}
+
+static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors,
+ QEMUIOVector *iov)
+{
+return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false);
+}
+
+static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors,
+ QEMUIOVector *iov)
+{
+return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true);
+}
+
+/**/
/* removable device support */
/**
diff --git a/trace-events b/trace-events
index 46bceca..bc9be30 100644
--- a/trace-events
+++ b/trace-events
@@ -68,6 +68,7 @@ disable bdrv_aio_writev(void *bs, int64_t sector_num, int
nb_sectors, void *opaq
disable bdrv_set_locked(void *bs, int locked) "bs %p locked %d"
disable bdrv_co_readv(void *bs, int64_t sector_num, int nb_sector) "bs %p
sector_num %"PRId64" nb_sectors %d"
disable bdrv_co_writev(void *bs, int64_t sector_num, int nb_sector) "bs %p
sector_num %"PRId64" nb_sectors %d"
+disable bdrv_co_io(int is_write, void *acb) "is_write %d acb %p"
# hw/virtio-blk.c
disable virtio_blk_req_complete(void *req, int status) "req %p status %d"
--
1.7.6
