@@ -2740,8 +2740,11 @@ int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
* BDRV_REQ_FUA).
*
* Returns < 0 on error, 0 on success. For error codes see bdrv_write().
+ *
+ * To be called between exactly one pair of bdrv_inc/dec_in_flight()
*/
-int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags)
+static int coroutine_fn
+bdrv_do_make_zero(BdrvChild *child, BdrvRequestFlags flags)
{
int ret;
int64_t target_size, bytes, offset = 0;
@@ -2757,7 +2760,8 @@ int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags)
if (bytes <= 0) {
return 0;
}
- ret = bdrv_block_status(bs, offset, bytes, &bytes, NULL, NULL);
+ ret = bdrv_co_block_status(bs, true, false,
+ offset, bytes, &bytes, NULL, NULL);
if (ret < 0) {
return ret;
}
@@ -2765,7 +2769,7 @@ int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags)
offset += bytes;
continue;
}
- ret = bdrv_pwrite_zeroes(child, offset, bytes, flags);
+ ret = bdrv_do_pwrite_zeroes(child, offset, bytes, flags);
if (ret < 0) {
return ret;
}
@@ -2773,6 +2777,50 @@ int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags)
}
}
+typedef struct BdrvDoMakeZeroData {
+ BdrvChild *child;
+ BdrvRequestFlags flags;
+ int ret;
+ bool done;
+} BdrvDoMakeZeroData;
+
+/* To be called between exactly one pair of bdrv_inc/dec_in_flight() */
+static void coroutine_fn bdrv_make_zero_co_entry(void *opaque)
+{
+ BdrvDoMakeZeroData *data = opaque;
+
+ data->ret = bdrv_do_make_zero(data->child, data->flags);
+ data->done = true;
+ aio_wait_kick();
+}
+
+int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags)
+{
+ int ret;
+
+ bdrv_inc_in_flight(child->bs);
+
+ if (qemu_in_coroutine()) {
+ /* Fast-path if already in coroutine context */
+ ret = bdrv_do_make_zero(child, flags);
+ } else {
+ BdrvDoMakeZeroData data = {
+ .child = child,
+ .flags = flags,
+ .done = false,
+ };
+ Coroutine *co = qemu_coroutine_create(bdrv_make_zero_co_entry, &data);
+
+ bdrv_coroutine_enter(child->bs, co);
+ BDRV_POLL_WHILE(child->bs, !data.done);
+ ret = data.ret;
+ }
+
+ bdrv_dec_in_flight(child->bs);
+
+ return ret;
+}
+
typedef struct BdrvVmstateCo {
BlockDriverState *bs;
QEMUIOVector *qiov;
It's safer to expand in_flight request to start before enter to coroutine in synchronous wrappers and end after BDRV_POLL_WHILE loop. Note that qemu_coroutine_enter may only schedule the coroutine in some circumstances. bdrv_make_zero update includes refactoring: move the whole loop into coroutine, which has additional benefit of not create/enter new coroutine on each iteration. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> --- block/io.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 51 insertions(+), 3 deletions(-)