From a659979328fb6d4d6100d398f5bd9a2310c3e169 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 17 May 2011 18:04:06 +0200 Subject: block: clarify the meaning of BDRV_O_NOCACHE Change BDRV_O_NOCACHE to only imply bypassing the host OS file cache, but no writeback semantics. All existing callers are changed to also specify BDRV_O_CACHE_WB to give them writeback semantics. Signed-off-by: Christoph Hellwig Signed-off-by: Kevin Wolf --- block.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) (limited to 'block.c') diff --git a/block.c b/block.c index effa86fd53..3036a2deed 100644 --- a/block.c +++ b/block.c @@ -439,13 +439,7 @@ static int bdrv_open_common(BlockDriverState *bs, const char *filename, bs->drv = drv; bs->opaque = qemu_mallocz(drv->instance_size); - /* - * Yes, BDRV_O_NOCACHE aka O_DIRECT means we have to present a - * write cache to the guest. We do need the fdatasync to flush - * out transactions for block allocations, and we maybe have a - * volatile write cache in our backing device to deal with. - */ - if (flags & (BDRV_O_CACHE_WB|BDRV_O_NOCACHE)) + if (flags & BDRV_O_CACHE_WB) bs->enable_write_cache = 1; /* -- cgit v1.2.3