diff options
| author | Marcelo Tosatti <mtosatti@redhat.com> | 2007-12-20 19:18:23 -0500 |
|---|---|---|
| committer | Avi Kivity <avi@qumranet.com> | 2008-01-30 18:01:20 +0200 |
| commit | 7ec54588210df29ea637e6054489bc942c0ef371 (patch) | |
| tree | a21f672f29965a7fa35d90b3c3fe034150ae9ec7 /arch/x86 | |
| parent | 10589a4699bb978c781ce73bbae8ca942c5250c9 (diff) | |
KVM: Add kvm_read_guest_atomic()
In preparation for a mmu spinlock, add kvm_read_guest_atomic()
and use it in fetch() and prefetch_page().
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/paging_tmpl.h | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 7f83f5557d5..136a65d72b0 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -316,10 +316,12 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, metaphysical, access, shadow_ent, &new_page); if (new_page && !metaphysical) { + int r; pt_element_t curr_pte; - kvm_read_guest(vcpu->kvm, walker->pte_gpa[level - 2], - &curr_pte, sizeof(curr_pte)); - if (curr_pte != walker->ptes[level - 2]) + r = kvm_read_guest_atomic(vcpu->kvm, + walker->pte_gpa[level - 2], + &curr_pte, sizeof(curr_pte)); + if (r || curr_pte != walker->ptes[level - 2]) return NULL; } shadow_addr = __pa(shadow_page->spt); @@ -429,9 +431,8 @@ static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr) static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) { - int i, offset = 0; - pt_element_t *gpt; - struct page *page; + int i, offset = 0, r = 0; + pt_element_t pt; if (sp->role.metaphysical || (PTTYPE == 32 && sp->role.level > PT_PAGE_TABLE_LEVEL)) { @@ -441,15 +442,18 @@ static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu, if (PTTYPE == 32) offset = sp->role.quadrant << PT64_LEVEL_BITS; - page = gfn_to_page(vcpu->kvm, sp->gfn); - gpt = kmap_atomic(page, KM_USER0); - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) - if (is_present_pte(gpt[offset + i])) + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + gpa_t pte_gpa = gfn_to_gpa(sp->gfn); + pte_gpa += (i+offset) * sizeof(pt_element_t); + + r = kvm_read_guest_atomic(vcpu->kvm, pte_gpa, &pt, + sizeof(pt_element_t)); + if (r || is_present_pte(pt)) sp->spt[i] = shadow_trap_nonpresent_pte; else sp->spt[i] = shadow_notrap_nonpresent_pte; - kunmap_atomic(gpt, KM_USER0); - kvm_release_page_clean(page); + } } #undef pt_element_t |