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Subject: Re: [PATCH 7/9] KVM: arm64: Simplify argument passing to
 vgic_uaccess_[read|write]
To:     Alexandru Elisei <alexandru.elisei@arm.com>,
        eric.auger.pro@gmail.com, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, maz@kernel.org,
        drjones@redhat.com
Cc:     shuah@kernel.org, pbonzini@redhat.com
References: <20201212185010.26579-1-eric.auger@redhat.com>
 <20201212185010.26579-8-eric.auger@redhat.com>
 <ee2ec95e-4262-a364-b037-c43f3d396760@arm.com>
 <e7af1e23-7b08-99d6-d78c-812d442b32ce@arm.com>
From:   Auger Eric <eric.auger@redhat.com>
Message-ID: <266b0ffc-c1a5-4939-975c-aea6a9248a2f@redhat.com>
Date:   Wed, 13 Jan 2021 18:18:19 +0100
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Hi Alexandru,
On 1/12/21 5:16 PM, Alexandru Elisei wrote:
> Hi Eric,
> 
> On 1/12/21 4:04 PM, Alexandru Elisei wrote:
>> Hi Eric,
>>
>> On 12/12/20 6:50 PM, Eric Auger wrote:
>>> Instead of converting the vgic_io_device handle to a kvm_io_device
>>> handled and then do the oppositive, pass a vgic_io_device pointer all
>>> along the call chain.
>> To me, it looks like the commit message describes what the patch does instead of
>> why it does it.
>>
>> What are "vgic_io_device handle" and "kvm_io_device handled"?
Yes unfortunate typo, sorry.
> 
> Sorry, I think I got it now. You were referring to the argument types struct
> vgic_io_device and struct kvm_io_device. The patch looks like a very good cleanup.
> 
> How changing to commit message to sound something like this (feel free to
> ignore/change it if you think of something else):
> 
> vgic_uaccess() takes a struct vgic_io_device argument, converts it to a struct
> kvm_io_device and passes it to the read/write accessor functions, which convert it
> back to a struct vgic_io_device. Avoid the indirection by passing the struct
> vgic_io_device argument directly to vgic_uaccess_{read,write).
I reworded the commit message as you suggested.

Thanks

Eric
> 
> Thanks,
> Alex
>>
>> Thanks,
>> Alex
>>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>>> ---
>>>  arch/arm64/kvm/vgic/vgic-mmio.c | 10 ++++------
>>>  1 file changed, 4 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/arch/arm64/kvm/vgic/vgic-mmio.c b/arch/arm64/kvm/vgic/vgic-mmio.c
>>> index b2d73fc0d1ef..48c6067fc5ec 100644
>>> --- a/arch/arm64/kvm/vgic/vgic-mmio.c
>>> +++ b/arch/arm64/kvm/vgic/vgic-mmio.c
>>> @@ -938,10 +938,9 @@ vgic_get_mmio_region(struct kvm_vcpu *vcpu, struct vgic_io_device *iodev,
>>>  	return region;
>>>  }
>>>  
>>> -static int vgic_uaccess_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
>>> +static int vgic_uaccess_read(struct kvm_vcpu *vcpu, struct vgic_io_device *iodev,
>>>  			     gpa_t addr, u32 *val)
>>>  {
>>> -	struct vgic_io_device *iodev = kvm_to_vgic_iodev(dev);
>>>  	const struct vgic_register_region *region;
>>>  	struct kvm_vcpu *r_vcpu;
>>>  
>>> @@ -960,10 +959,9 @@ static int vgic_uaccess_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
>>>  	return 0;
>>>  }
>>>  
>>> -static int vgic_uaccess_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
>>> +static int vgic_uaccess_write(struct kvm_vcpu *vcpu, struct vgic_io_device *iodev,
>>>  			      gpa_t addr, const u32 *val)
>>>  {
>>> -	struct vgic_io_device *iodev = kvm_to_vgic_iodev(dev);
>>>  	const struct vgic_register_region *region;
>>>  	struct kvm_vcpu *r_vcpu;
>>>  
>>> @@ -986,9 +984,9 @@ int vgic_uaccess(struct kvm_vcpu *vcpu, struct vgic_io_device *dev,
>>>  		 bool is_write, int offset, u32 *val)
>>>  {
>>>  	if (is_write)
>>> -		return vgic_uaccess_write(vcpu, &dev->dev, offset, val);
>>> +		return vgic_uaccess_write(vcpu, dev, offset, val);
>>>  	else
>>> -		return vgic_uaccess_read(vcpu, &dev->dev, offset, val);
>>> +		return vgic_uaccess_read(vcpu, dev, offset, val);
>>>  }
>>>  
>>>  static int dispatch_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
>> _______________________________________________
>> kvmarm mailing list
>> kvmarm@lists.cs.columbia.edu
>> https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
>