KVM: MMU: make rmap code aware of mapping levels

This patch removes the largepage parameter from the rmap_add function.
Together with rmap_remove this function now uses the role.level field to
find determine if the page is a huge page.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 86c2551..b93ad2c 100644 (file)
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -479,19 +479,19 @@ static int is_largepage_backed(struct kvm_vcpu *vcpu, gfn_t large_gfn)
  * Note: gfn must be unaliased before this function get called
  */
 
-static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int lpage)
+static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int level)
 {
        struct kvm_memory_slot *slot;
        unsigned long idx;
 
        slot = gfn_to_memslot(kvm, gfn);
-       if (!lpage)
+       if (likely(level == PT_PAGE_TABLE_LEVEL))
                return &slot->rmap[gfn - slot->base_gfn];
 
-       idx = (gfn / KVM_PAGES_PER_HPAGE(PT_DIRECTORY_LEVEL)) -
-             (slot->base_gfn / KVM_PAGES_PER_HPAGE(PT_DIRECTORY_LEVEL));
+       idx = (gfn / KVM_PAGES_PER_HPAGE(level)) -
+               (slot->base_gfn / KVM_PAGES_PER_HPAGE(level));
 
-       return &slot->lpage_info[0][idx].rmap_pde;
+       return &slot->lpage_info[level - 2][idx].rmap_pde;
 }
 
 /*
@@ -507,7 +507,7 @@ static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int lpage)
  * the spte was not added.
  *
  */
-static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn, int lpage)
+static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
 {
        struct kvm_mmu_page *sp;
        struct kvm_rmap_desc *desc;
@@ -519,7 +519,7 @@ static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn, int lpage)
        gfn = unalias_gfn(vcpu->kvm, gfn);
        sp = page_header(__pa(spte));
        sp->gfns[spte - sp->spt] = gfn;
-       rmapp = gfn_to_rmap(vcpu->kvm, gfn, lpage);
+       rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level);
        if (!*rmapp) {
                rmap_printk("rmap_add: %p %llx 0->1\n", spte, *spte);
                *rmapp = (unsigned long)spte;
@@ -589,7 +589,7 @@ static void rmap_remove(struct kvm *kvm, u64 *spte)
                kvm_release_pfn_dirty(pfn);
        else
                kvm_release_pfn_clean(pfn);
-       rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt], is_large_pte(*spte));
+       rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt], sp->role.level);
        if (!*rmapp) {
                printk(KERN_ERR "rmap_remove: %p %llx 0->BUG\n", spte, *spte);
                BUG();
@@ -652,10 +652,10 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn)
 {
        unsigned long *rmapp;
        u64 *spte;
-       int write_protected = 0;
+       int i, write_protected = 0;
 
        gfn = unalias_gfn(kvm, gfn);
-       rmapp = gfn_to_rmap(kvm, gfn, 0);
+       rmapp = gfn_to_rmap(kvm, gfn, PT_PAGE_TABLE_LEVEL);
 
        spte = rmap_next(kvm, rmapp, NULL);
        while (spte) {
@@ -677,21 +677,24 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn)
        }
 
        /* check for huge page mappings */
-       rmapp = gfn_to_rmap(kvm, gfn, 1);
-       spte = rmap_next(kvm, rmapp, NULL);
-       while (spte) {
-               BUG_ON(!spte);
-               BUG_ON(!(*spte & PT_PRESENT_MASK));
-               BUG_ON((*spte & (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)) != (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK));
-               pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte, *spte, gfn);
-               if (is_writeble_pte(*spte)) {
-                       rmap_remove(kvm, spte);
-                       --kvm->stat.lpages;
-                       __set_spte(spte, shadow_trap_nonpresent_pte);
-                       spte = NULL;
-                       write_protected = 1;
+       for (i = PT_DIRECTORY_LEVEL;
+            i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) {
+               rmapp = gfn_to_rmap(kvm, gfn, i);
+               spte = rmap_next(kvm, rmapp, NULL);
+               while (spte) {
+                       BUG_ON(!spte);
+                       BUG_ON(!(*spte & PT_PRESENT_MASK));
+                       BUG_ON((*spte & (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)) != (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK));
+                       pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte, *spte, gfn);
+                       if (is_writeble_pte(*spte)) {
+                               rmap_remove(kvm, spte);
+                               --kvm->stat.lpages;
+                               __set_spte(spte, shadow_trap_nonpresent_pte);
+                               spte = NULL;
+                               write_protected = 1;
+                       }
+                       spte = rmap_next(kvm, rmapp, spte);
                }
-               spte = rmap_next(kvm, rmapp, spte);
        }
 
        return write_protected;
@@ -1815,7 +1818,7 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 
        page_header_update_slot(vcpu->kvm, sptep, gfn);
        if (!was_rmapped) {
-               rmap_count = rmap_add(vcpu, sptep, gfn, largepage);
+               rmap_count = rmap_add(vcpu, sptep, gfn);
                if (!is_rmap_spte(*sptep))
                        kvm_release_pfn_clean(pfn);
                if (rmap_count > RMAP_RECYCLE_THRESHOLD)