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 <wrfsh@yandex-team.ru>
Message-Id: <1572978137-189218-1-git-send-email-wrfsh@yandex-team.ru>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Evgeny Yakovlev 2019-11-05 21:22:17 +03:00 committed by Stefan Hajnoczi
parent b0ca999a43
commit 5f2585772f
9 changed files with 19 additions and 2 deletions

View File

@ -2149,6 +2149,7 @@ type_init(machvirt_machine_init);
static void virt_machine_4_2_options(MachineClass *mc)
{
compat_props_add(mc->compat_props, hw_compat_4_2, hw_compat_4_2_len);
}
DEFINE_VIRT_MACHINE_AS_LATEST(4, 2)

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@ -991,7 +991,9 @@ static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features,
virtio_add_feature(&features, VIRTIO_BLK_F_SCSI);
}
if (blk_enable_write_cache(s->blk)) {
if (blk_enable_write_cache(s->blk) ||
(s->conf.x_enable_wce_if_config_wce &&
virtio_has_feature(features, VIRTIO_BLK_F_CONFIG_WCE))) {
virtio_add_feature(&features, VIRTIO_BLK_F_WCE);
}
if (blk_is_read_only(s->blk)) {
@ -1270,6 +1272,8 @@ static Property virtio_blk_properties[] = {
conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS),
DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock,
conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS),
DEFINE_PROP_BOOL("x-enable-wce-if-config-wce", VirtIOBlock,
conf.x_enable_wce_if_config_wce, true),
DEFINE_PROP_END_OF_LIST(),
};

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@ -27,6 +27,11 @@
#include "hw/pci/pci.h"
#include "hw/mem/nvdimm.h"
GlobalProperty hw_compat_4_2[] = {
{ "virtio-blk-device", "x-enable-wce-if-config-wce", "off" },
};
const size_t hw_compat_4_2_len = G_N_ELEMENTS(hw_compat_4_2);
GlobalProperty hw_compat_4_1[] = {
{ "virtio-pci", "x-pcie-flr-init", "off" },
};

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@ -431,6 +431,7 @@ static void pc_i440fx_4_2_machine_options(MachineClass *m)
m->alias = "pc";
m->is_default = 1;
pcmc->default_cpu_version = 1;
compat_props_add(m->compat_props, hw_compat_4_2, hw_compat_4_2_len);
}
DEFINE_I440FX_MACHINE(v4_2, "pc-i440fx-4.2", NULL,

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@ -354,6 +354,7 @@ static void pc_q35_4_2_machine_options(MachineClass *m)
pc_q35_machine_options(m);
m->alias = "q35";
pcmc->default_cpu_version = 1;
compat_props_add(m->compat_props, hw_compat_4_2, hw_compat_4_2_len);
}
DEFINE_Q35_MACHINE(v4_2, "pc-q35-4.2", NULL,

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@ -4496,7 +4496,7 @@ static const TypeInfo spapr_machine_info = {
*/
static void spapr_machine_4_2_class_options(MachineClass *mc)
{
/* Defaults for the latest behaviour inherited from the base class */
compat_props_add(mc->compat_props, hw_compat_4_2, hw_compat_4_2_len);
}
DEFINE_SPAPR_MACHINE(4_2, "4.2", true);

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@ -645,6 +645,7 @@ static void ccw_machine_4_2_instance_options(MachineState *machine)
static void ccw_machine_4_2_class_options(MachineClass *mc)
{
compat_props_add(mc->compat_props, hw_compat_4_2, hw_compat_4_2_len);
}
DEFINE_CCW_MACHINE(4_2, "4.2", true);

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@ -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;

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@ -40,6 +40,7 @@ struct VirtIOBlkConf
uint16_t queue_size;
uint32_t max_discard_sectors;
uint32_t max_write_zeroes_sectors;
bool x_enable_wce_if_config_wce;
};
struct VirtIOBlockDataPlane;