Re: [PATCH v3 03/11] KVM: MMU: introduce kvm_mmu_slot_gfn_write_protect

From: Paolo Bonzini
Date: Fri Feb 19 2016 - 06:18:30 EST




On 14/02/2016 12:31, Xiao Guangrong wrote:
> Split rmap_write_protect() and introduce the function to abstract the write
> protection based on the slot
>
> This function will be used in the later patch
>
> Signed-off-by: Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>
> ---
> arch/x86/kvm/mmu.c | 16 +++++++++++-----
> arch/x86/kvm/mmu.h | 2 ++
> 2 files changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
> index e1bb66c..edad3c7 100644
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -1336,23 +1336,29 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
> kvm_mmu_write_protect_pt_masked(kvm, slot, gfn_offset, mask);
> }
>
> -static bool rmap_write_protect(struct kvm_vcpu *vcpu, u64 gfn)
> +bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
> + struct kvm_memory_slot *slot, u64 gfn)
> {
> - struct kvm_memory_slot *slot;
> struct kvm_rmap_head *rmap_head;
> int i;
> bool write_protected = false;
>
> - slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
> -
> for (i = PT_PAGE_TABLE_LEVEL; i <= PT_MAX_HUGEPAGE_LEVEL; ++i) {
> rmap_head = __gfn_to_rmap(gfn, i, slot);
> - write_protected |= __rmap_write_protect(vcpu->kvm, rmap_head, true);
> + write_protected |= __rmap_write_protect(kvm, rmap_head, true);
> }
>
> return write_protected;
> }
>
> +static bool rmap_write_protect(struct kvm_vcpu *vcpu, u64 gfn)
> +{
> + struct kvm_memory_slot *slot;
> +
> + slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
> + return kvm_mmu_slot_gfn_write_protect(vcpu->kvm, slot, gfn);
> +}
> +
> static bool kvm_zap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head)
> {
> u64 *sptep;
> diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
> index de92bed..58fe98a 100644
> --- a/arch/x86/kvm/mmu.h
> +++ b/arch/x86/kvm/mmu.h
> @@ -177,4 +177,6 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end);
>
> void kvm_mmu_gfn_disallow_lpage(struct kvm_memory_slot *slot, gfn_t gfn);
> void kvm_mmu_gfn_allow_lpage(struct kvm_memory_slot *slot, gfn_t gfn);
> +bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
> + struct kvm_memory_slot *slot, u64 gfn);
> #endif
>

Reviewed-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>