From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v2 07/13] KVM: add vcpu-specific functions to read/write/translate
 GFNs
Date: Fri, 05 Jun 2015 12:26:35 +0200
Message-ID: <5571795B.6080204@redhat.com>
References: <1432746314-50196-1-git-send-email-pbonzini@redhat.com> <1432746314-50196-8-git-send-email-pbonzini@redhat.com> <20150529192346.GA11651@potion.brq.redhat.com>
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Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	guangrong.xiao@linux.intel.com, bdas@redhat.com
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On 29/05/2015 21:23, Radim Kr=C4=8Dm=C3=A1=C5=99 wrote:
>> > +int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const =
void *data,
>> > +		         unsigned long len)
>> > +{
>> > +	gfn_t gfn =3D gpa >> PAGE_SHIFT;
>> > +	int seg;
>> > +	int offset =3D offset_in_page(gpa);
>> > +	int ret;
>> > +
>> > +	while ((seg =3D next_segment(len, offset)) !=3D 0) {
>> > +		ret =3D kvm_vcpu_write_guest_page(vcpu, gfn, data, offset, seg)=
;
>> > +		if (ret < 0)
>> > +			return ret;
>> > +		offset =3D 0;
>> > +		len -=3D seg;
>> > +		data +=3D seg;
>> > +		++gfn;
>> > +	}
>> > +	return 0;
>> > +}
> (There is no need to pass vcpu, and kvm, in this API.

How so?  A single kvm_vcpu_write_guest can cross multiple slots.

Paolo

>  Extracting memslots early will help to keep more code common.
>=20
>  I have patches that did a superset of this for the old API, so posti=
ng
>  them after this series is finalized will be simple.)