lkml.org 
[lkml]   [2007]   [Jul]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC 6/8]KVM: introduce kvm_mmu_zap_pagetbl
Shaohua Li wrote:
> add a routine to zap all shadow pgtble for a gfn. If kvm supports SMP,
> the API should zap pgtble for all vcpus, but kvm shadow page table
> really should be per-vm, instead of per-vcpu.
>
>

kvm shadow page tables _are_ per-vm. Current kvm.git even makes that
more explicit where functions that remove stuff (like rmap_remove())
don't require a vcpu.


> Index: linux/drivers/kvm/kvm.h
> ===================================================================
> --- linux.orig/drivers/kvm/kvm.h 2007-07-20 14:19:15.000000000 +0800
> +++ linux/drivers/kvm/kvm.h 2007-07-20 14:26:10.000000000 +0800
> @@ -621,6 +621,7 @@ int kvm_mmu_unprotect_page_virt(struct k
> void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu);
> int kvm_mmu_load(struct kvm_vcpu *vcpu);
> void kvm_mmu_unload(struct kvm_vcpu *vcpu);
> +void kvm_mmu_zap_pagetbl(struct kvm_vcpu *vcpu, u64 gfn);
>
> int kvm_hypercall(struct kvm_vcpu *vcpu, struct kvm_run *run);
>
> Index: linux/drivers/kvm/mmu.c
> ===================================================================
> --- linux.orig/drivers/kvm/mmu.c 2007-07-20 14:25:25.000000000 +0800
> +++ linux/drivers/kvm/mmu.c 2007-07-20 14:26:10.000000000 +0800
> @@ -1324,6 +1324,34 @@ void kvm_mmu_zap_all(struct kvm_vcpu *vc
> init_kvm_mmu(vcpu);
> }
>
> +/* FIXME: this should zap all vcpu's shadow pgtbl for gfn */
> +void kvm_mmu_zap_pagetbl(struct kvm_vcpu *vcpu, u64 gfn)
> +{
> + struct kvm *kvm = vcpu->kvm;
> + struct kvm_rmap_desc *desc;
> + struct page *page;
> + u64 *spte;
> +
> + page = gfn_to_page(kvm, gfn);
> + BUG_ON(!page);
> +
> + while (page_private(page)) {
> + if (!(page_private(page) & 1))
> + spte = (u64 *)page_private(page);
> + else {
> + desc = (struct kvm_rmap_desc *)(page_private(page) & ~1ul);
> + spte = desc->shadow_ptes[0];
> + }
> + BUG_ON(!spte);
> + BUG_ON((*spte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT
> + != page_to_pfn(page));
> + BUG_ON(!(*spte & PT_PRESENT_MASK));
> + rmap_remove(vcpu, spte);
> + *spte = 0;
> + }
> + kvm_flush_remote_tlbs(vcpu->kvm);
> +}
> +

Suggest kvm_mmu_unmap_page() as a name for this.


--
error compiling committee.c: too many arguments to function

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-07-23 13:19    [W:0.052 / U:0.148 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site