From 5f2585772fff7ada93cb6691c51603451228a09c Mon Sep 17 00:00:00 2001 From: Evgeny Yakovlev Date: Tue, 5 Nov 2019 21:22:17 +0300 Subject: virtio-blk: advertise F_WCE (F_FLUSH) if F_CONFIG_WCE is advertised Virtio spec 1.1 (and earlier), 5.2.5.2 Driver Requirements: Device Initialization: "Devices SHOULD always offer VIRTIO_BLK_F_FLUSH, and MUST offer it if they offer VIRTIO_BLK_F_CONFIG_WCE" Currently F_CONFIG_WCE and F_WCE are not connected to each other. Qemu will advertise F_CONFIG_WCE if config-wce argument is set for virtio-blk device. And F_WCE is advertised only if underlying block backend actually has it's caching enabled. Fix this by advertising F_WCE if F_CONFIG_WCE is also advertised. To preserve backwards compatibility with newer machine types make this behaviour governed by "x-enable-wce-if-config-wce" virtio-blk-device property and introduce hw_compat_4_2 with new property being off by default for all machine types <= 4.2 (but don't introduce 4.3 machine type itself yet). Signed-off-by: Evgeny Yakovlev Message-Id: <1572978137-189218-1-git-send-email-wrfsh@yandex-team.ru> Signed-off-by: Stefan Hajnoczi --- include/hw/boards.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/hw/boards.h') diff --git a/include/hw/boards.h b/include/hw/boards.h index de45087f34..24cbeecbae 100644 --- a/include/hw/boards.h +++ b/include/hw/boards.h @@ -329,6 +329,9 @@ struct MachineState { } \ type_init(machine_initfn##_register_types) +extern GlobalProperty hw_compat_4_2[]; +extern const size_t hw_compat_4_2_len; + extern GlobalProperty hw_compat_4_1[]; extern const size_t hw_compat_4_1_len; -- cgit v1.2.3-55-g7522