[PATCH 15/19] KVM: PPC: Book3S HV: add get/set accessors for the source configuration

[Cédric Le Goater]

On 2/5/19 6:32 AM, David Gibson wrote:
> On Mon, Feb 04, 2019 at 05:07:28PM +0100, Cédric Le Goater wrote:
>> On 2/4/19 6:21 AM, David Gibson wrote:
>>> On Mon, Jan 07, 2019 at 07:43:27PM +0100, Cédric Le Goater wrote:
>>>> Theses are use to capure the XIVE EAS table of the KVM device, the
>>>> configuration of the source targets.
>>>>
>>>> Signed-off-by: Cédric Le Goater <clg at kaod.org>
>>>> ---
>>>>  arch/powerpc/include/uapi/asm/kvm.h   | 11 ++++
>>>>  arch/powerpc/kvm/book3s_xive_native.c | 87 +++++++++++++++++++++++++++
>>>>  2 files changed, 98 insertions(+)
>>>>
>>>> diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h
>>>> index 1a8740629acf..faf024f39858 100644
>>>> --- a/arch/powerpc/include/uapi/asm/kvm.h
>>>> +++ b/arch/powerpc/include/uapi/asm/kvm.h
>>>> @@ -683,9 +683,20 @@ struct kvm_ppc_cpu_char {
>>>>  #define   KVM_DEV_XIVE_SAVE_EQ_PAGES	4
>>>>  #define KVM_DEV_XIVE_GRP_SOURCES	2	/* 64-bit source attributes */
>>>>  #define KVM_DEV_XIVE_GRP_SYNC		3	/* 64-bit source attributes */
>>>> +#define KVM_DEV_XIVE_GRP_EAS		4	/* 64-bit eas attributes */
>>>>  
>>>>  /* Layout of 64-bit XIVE source attribute values */
>>>>  #define KVM_XIVE_LEVEL_SENSITIVE	(1ULL << 0)
>>>>  #define KVM_XIVE_LEVEL_ASSERTED		(1ULL << 1)
>>>>  
>>>> +/* Layout of 64-bit eas attribute values */
>>>> +#define KVM_XIVE_EAS_PRIORITY_SHIFT	0
>>>> +#define KVM_XIVE_EAS_PRIORITY_MASK	0x7
>>>> +#define KVM_XIVE_EAS_SERVER_SHIFT	3
>>>> +#define KVM_XIVE_EAS_SERVER_MASK	0xfffffff8ULL
>>>> +#define KVM_XIVE_EAS_MASK_SHIFT		32
>>>> +#define KVM_XIVE_EAS_MASK_MASK		0x100000000ULL
>>>> +#define KVM_XIVE_EAS_EISN_SHIFT		33
>>>> +#define KVM_XIVE_EAS_EISN_MASK		0xfffffffe00000000ULL
>>>> +
>>>>  #endif /* __LINUX_KVM_POWERPC_H */
>>>> diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c
>>>> index f2de1bcf3b35..0468b605baa7 100644
>>>> --- a/arch/powerpc/kvm/book3s_xive_native.c
>>>> +++ b/arch/powerpc/kvm/book3s_xive_native.c
>>>> @@ -525,6 +525,88 @@ static int kvmppc_xive_native_sync(struct kvmppc_xive *xive, long irq, u64 addr)
>>>>  	return 0;
>>>>  }
>>>>  
>>>> +static int kvmppc_xive_native_set_eas(struct kvmppc_xive *xive, long irq,
>>>> +				      u64 addr)
>>>
>>> I'd prefer to avoid the name "EAS" here.  IIUC these aren't "raw" EAS
>>> values, but rather essentially the "source config" in the terminology
>>> of the PAPR hcalls.  Which, yes, is basically implemented by setting
>>> the EAS, but since it's the PAPR architected state that we need to
>>> preserve across migration, I'd prefer to stick as close as we can to
>>> the PAPR terminology.
>>
>> But we don't have an equivalent name in the PAPR specs for the tuple 
>> (prio, server). We could use the generic 'target' name may be ? even 
>> if this is usually referring to a CPU number.
> 
> Um.. what?  That's about terminology for one of the fields in this
> thing, not about the name for the thing itself.
> 
>> Or, IVE (Interrupt Vector Entry) ? which makes some sense. 
>> This is was the former name in HW. I think we recycle it for KVM.
> 
> That's a terrible idea, which will make a confusing situation even
> more confusing.

Let's use SOURCE_CONFIG and QUEUE_CONFIG. The KVM ioctls are very 
similar to the hcalls anyhow.

C.