From c1a149658ffb385f55e8bb06f06b6d195b91fd1b Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Mon, 9 Sep 2013 14:28:03 +0200 Subject: [PATCH 12/38] block: Always enable discard on the protocol level RH-Author: Kevin Wolf Message-id: <1378736903-18489-13-git-send-email-kwolf@redhat.com> Patchwork-id: 54196 O-Subject: [RHEL-7.0 qemu-kvm PATCH 12/32] block: Always enable discard on the protocol level Bugzilla: 1005818 RH-Acked-by: Fam Zheng RH-Acked-by: Max Reitz RH-Acked-by: Miroslav Rezanina Bugzilla: 1005818 Turning on discard options in qcow2 doesn't help a lot when the discard requests that it issues are thrown away by the raw-posix layer. This patch always enables discard functionality on the protocol level so that it's the image format's responsibility to send (or not) discard requests. Requests sent by the guest will be allowed or ignored by the top level BlockDriverState, which depends on the discard=... option like before. In particular, this means that even without specifying options, the qcow2 default of discarding deleted snapshots actually takes effect now, both for qemu and qemu-img. Signed-off-by: Kevin Wolf Signed-off-by: Stefan Hajnoczi (cherry picked from commit 50b05b6f2e24296b4d739a638e1e7427767ed7cd) Signed-off-by: Kevin Wolf --- block.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Signed-off-by: Miroslav Rezanina --- block.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/block.c b/block.c index 2584ec7..20820fa 100644 --- a/block.c +++ b/block.c @@ -1055,7 +1055,7 @@ int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options, extract_subqdict(options, &file_options, "file."); ret = bdrv_file_open(&file, filename, file_options, - bdrv_open_flags(bs, flags)); + bdrv_open_flags(bs, flags | BDRV_O_UNMAP)); if (ret < 0) { goto fail; } -- 1.7.1