Commit df702c9b authored Jan 14, 2013 by Paolo Bonzini Committed by Stefan Hajnoczi Jan 15, 2013

block: clear dirty bitmap when discarding



Note that resetting bits in the dirty bitmap is done _before_ actually
processing the request.  Writes, instead, set bits after the request
is completed.

This way, when there are concurrent write and discard requests, the
outcome will always be that the blocks are marked dirty.  This scenario
should never happen, but it is safer to do it this way.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

parent 501378c3

block.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -4170,7 +4170,13 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
		return -EIO;
		} else if (bs->read_only) {
		return -EROFS;
		} else if (bs->drv->bdrv_co_discard) {
		}

		if (bs->dirty_bitmap) {
		set_dirty_bitmap(bs, sector_num, nb_sectors, 0);
		}

		if (bs->drv->bdrv_co_discard) {
		return bs->drv->bdrv_co_discard(bs, sector_num, nb_sectors);
		} else if (bs->drv->bdrv_aio_discard) {
		BlockDriverAIOCB *acb;