Re: [PATCH v2 1/4] x86/hyper-v: move synic/stimer control structures definitions to hyperv-tlfs.h

From: Roman Kagan
Date: Mon Nov 26 2018 - 15:04:34 EST


[ Sorry for having missed v1 ]

On Mon, Nov 26, 2018 at 04:47:29PM +0100, Vitaly Kuznetsov wrote:
> We implement Hyper-V SynIC and synthetic timers in KVM too so there's some
> room for code sharing.
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> ---
> arch/x86/include/asm/hyperv-tlfs.h | 69 ++++++++++++++++++++++++++++++
> drivers/hv/hv.c | 2 +-
> drivers/hv/hyperv_vmbus.h | 68 -----------------------------
> 3 files changed, 70 insertions(+), 69 deletions(-)
>
> diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
> index 4139f7650fe5..b032c05cd3ee 100644
> --- a/arch/x86/include/asm/hyperv-tlfs.h
> +++ b/arch/x86/include/asm/hyperv-tlfs.h
> @@ -731,6 +731,75 @@ struct hv_enlightened_vmcs {
> #define HV_STIMER_AUTOENABLE (1ULL << 3)
> #define HV_STIMER_SINT(config) (__u8)(((config) >> 16) & 0x0F)
>
> +/* Define synthetic interrupt controller flag constants. */
> +#define HV_EVENT_FLAGS_COUNT (256 * 8)
> +#define HV_EVENT_FLAGS_LONG_COUNT (256 / sizeof(unsigned long))
> +
> +/*
> + * Synthetic timer configuration.
> + */
> +union hv_stimer_config {
> + u64 as_uint64;
> + struct {
> + u64 enable:1;
> + u64 periodic:1;
> + u64 lazy:1;
> + u64 auto_enable:1;
> + u64 apic_vector:8;
> + u64 direct_mode:1;
> + u64 reserved_z0:3;
> + u64 sintx:4;
> + u64 reserved_z1:44;
> + };
> +};
> +
> +
> +/* Define the synthetic interrupt controller event flags format. */
> +union hv_synic_event_flags {
> + unsigned long flags[HV_EVENT_FLAGS_LONG_COUNT];
> +};
> +
> +/* Define SynIC control register. */
> +union hv_synic_scontrol {
> + u64 as_uint64;
> + struct {
> + u64 enable:1;
> + u64 reserved:63;
> + };
> +};
> +
> +/* Define synthetic interrupt source. */
> +union hv_synic_sint {
> + u64 as_uint64;
> + struct {
> + u64 vector:8;
> + u64 reserved1:8;
> + u64 masked:1;
> + u64 auto_eoi:1;
> + u64 reserved2:46;
> + };
> +};
> +
> +/* Define the format of the SIMP register */
> +union hv_synic_simp {
> + u64 as_uint64;
> + struct {
> + u64 simp_enabled:1;
> + u64 preserved:11;
> + u64 base_simp_gpa:52;
> + };
> +};
> +
> +/* Define the format of the SIEFP register */
> +union hv_synic_siefp {
> + u64 as_uint64;
> + struct {
> + u64 siefp_enabled:1;
> + u64 preserved:11;
> + u64 base_siefp_gpa:52;
> + };
> +};
> +
> struct hv_vpset {
> u64 format;
> u64 valid_bank_mask;

I personally tend to prefer masks over bitfields, so I'd rather do the
consolidation in the opposite direction: use the definitions in
hyperv-tlfs.h and replace those unions/bitfields elsewhere. (I vaguely
remember posting such a patchset a couple of years ago but I lacked the
motivation to complete it).

Roman.