KVM: MMU: large page support
[linux-2.6.git] / arch / x86 / kvm / paging_tmpl.h
index 4b55f46..17f9d16 100644 (file)
@@ -248,6 +248,7 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
        pt_element_t gpte;
        unsigned pte_access;
        struct page *npage;
+       int largepage = vcpu->arch.update_pte.largepage;
 
        gpte = *(const pt_element_t *)pte;
        if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) {
@@ -264,7 +265,8 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
                return;
        get_page(npage);
        mmu_set_spte(vcpu, spte, page->role.access, pte_access, 0, 0,
-                    gpte & PT_DIRTY_MASK, NULL, gpte_to_gfn(gpte), npage);
+                    gpte & PT_DIRTY_MASK, NULL, largepage, gpte_to_gfn(gpte),
+                    npage);
 }
 
 /*
@@ -272,8 +274,8 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
  */
 static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
                         struct guest_walker *walker,
-                        int user_fault, int write_fault, int *ptwrite,
-                        struct page *page)
+                        int user_fault, int write_fault, int largepage,
+                        int *ptwrite, struct page *page)
 {
        hpa_t shadow_addr;
        int level;
@@ -301,11 +303,19 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
                shadow_ent = ((u64 *)__va(shadow_addr)) + index;
                if (level == PT_PAGE_TABLE_LEVEL)
                        break;
-               if (is_shadow_present_pte(*shadow_ent)) {
+
+               if (largepage && level == PT_DIRECTORY_LEVEL)
+                       break;
+
+               if (is_shadow_present_pte(*shadow_ent)
+                   && !is_large_pte(*shadow_ent)) {
                        shadow_addr = *shadow_ent & PT64_BASE_ADDR_MASK;
                        continue;
                }
 
+               if (is_large_pte(*shadow_ent))
+                       rmap_remove(vcpu->kvm, shadow_ent);
+
                if (level - 1 == PT_PAGE_TABLE_LEVEL
                    && walker->level == PT_DIRECTORY_LEVEL) {
                        metaphysical = 1;
@@ -339,7 +349,7 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
        mmu_set_spte(vcpu, shadow_ent, access, walker->pte_access & access,
                     user_fault, write_fault,
                     walker->ptes[walker->level-1] & PT_DIRTY_MASK,
-                    ptwrite, walker->gfn, page);
+                    ptwrite, largepage, walker->gfn, page);
 
        return shadow_ent;
 }
@@ -369,6 +379,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
        int write_pt = 0;
        int r;
        struct page *page;
+       int largepage = 0;
 
        pgprintk("%s: addr %lx err %x\n", __FUNCTION__, addr, error_code);
        kvm_mmu_audit(vcpu, "pre page fault");
@@ -396,6 +407,14 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
        }
 
        down_read(&current->mm->mmap_sem);
+       if (walker.level == PT_DIRECTORY_LEVEL) {
+               gfn_t large_gfn;
+               large_gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE-1);
+               if (is_largepage_backed(vcpu, large_gfn)) {
+                       walker.gfn = large_gfn;
+                       largepage = 1;
+               }
+       }
        page = gfn_to_page(vcpu->kvm, walker.gfn);
        up_read(&current->mm->mmap_sem);
 
@@ -410,7 +429,8 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
        spin_lock(&vcpu->kvm->mmu_lock);
        kvm_mmu_free_some_pages(vcpu);
        shadow_pte = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault,
-                                 &write_pt, page);
+                                 largepage, &write_pt, page);
+
        pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __FUNCTION__,
                 shadow_pte, *shadow_pte, write_pt);