KVM: MMU: add TDP support to the KVM MMU
This patch contains the changes to the KVM MMU necessary for support of the
Nested Paging feature in AMD Barcelona and Phenom Processors.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 33cd7c9..f7541fe 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1097,6 +1097,7 @@
int i;
gfn_t root_gfn;
struct kvm_mmu_page *sp;
+ int metaphysical = 0;
root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT;
@@ -1105,14 +1106,20 @@
hpa_t root = vcpu->arch.mmu.root_hpa;
ASSERT(!VALID_PAGE(root));
+ if (tdp_enabled)
+ metaphysical = 1;
sp = kvm_mmu_get_page(vcpu, root_gfn, 0,
- PT64_ROOT_LEVEL, 0, ACC_ALL, NULL);
+ PT64_ROOT_LEVEL, metaphysical,
+ ACC_ALL, NULL);
root = __pa(sp->spt);
++sp->root_count;
vcpu->arch.mmu.root_hpa = root;
return;
}
#endif
+ metaphysical = !is_paging(vcpu);
+ if (tdp_enabled)
+ metaphysical = 1;
for (i = 0; i < 4; ++i) {
hpa_t root = vcpu->arch.mmu.pae_root[i];
@@ -1126,7 +1133,7 @@
} else if (vcpu->arch.mmu.root_level == 0)
root_gfn = 0;
sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30,
- PT32_ROOT_LEVEL, !is_paging(vcpu),
+ PT32_ROOT_LEVEL, metaphysical,
ACC_ALL, NULL);
root = __pa(sp->spt);
++sp->root_count;
@@ -1160,6 +1167,36 @@
error_code & PFERR_WRITE_MASK, gfn);
}
+static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa,
+ u32 error_code)
+{
+ struct page *page;
+ int r;
+
+ ASSERT(vcpu);
+ ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa));
+
+ r = mmu_topup_memory_caches(vcpu);
+ if (r)
+ return r;
+
+ down_read(¤t->mm->mmap_sem);
+ page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT);
+ if (is_error_page(page)) {
+ kvm_release_page_clean(page);
+ up_read(¤t->mm->mmap_sem);
+ return 1;
+ }
+ spin_lock(&vcpu->kvm->mmu_lock);
+ kvm_mmu_free_some_pages(vcpu);
+ r = __direct_map(vcpu, gpa, error_code & PFERR_WRITE_MASK,
+ gpa >> PAGE_SHIFT, page, TDP_ROOT_LEVEL);
+ spin_unlock(&vcpu->kvm->mmu_lock);
+ up_read(¤t->mm->mmap_sem);
+
+ return r;
+}
+
static void nonpaging_free(struct kvm_vcpu *vcpu)
{
mmu_free_roots(vcpu);
@@ -1253,7 +1290,35 @@
return paging64_init_context_common(vcpu, PT32E_ROOT_LEVEL);
}
-static int init_kvm_mmu(struct kvm_vcpu *vcpu)
+static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
+{
+ struct kvm_mmu *context = &vcpu->arch.mmu;
+
+ context->new_cr3 = nonpaging_new_cr3;
+ context->page_fault = tdp_page_fault;
+ context->free = nonpaging_free;
+ context->prefetch_page = nonpaging_prefetch_page;
+ context->shadow_root_level = TDP_ROOT_LEVEL;
+ context->root_hpa = INVALID_PAGE;
+
+ if (!is_paging(vcpu)) {
+ context->gva_to_gpa = nonpaging_gva_to_gpa;
+ context->root_level = 0;
+ } else if (is_long_mode(vcpu)) {
+ context->gva_to_gpa = paging64_gva_to_gpa;
+ context->root_level = PT64_ROOT_LEVEL;
+ } else if (is_pae(vcpu)) {
+ context->gva_to_gpa = paging64_gva_to_gpa;
+ context->root_level = PT32E_ROOT_LEVEL;
+ } else {
+ context->gva_to_gpa = paging32_gva_to_gpa;
+ context->root_level = PT32_ROOT_LEVEL;
+ }
+
+ return 0;
+}
+
+static int init_kvm_softmmu(struct kvm_vcpu *vcpu)
{
ASSERT(vcpu);
ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
@@ -1268,6 +1333,14 @@
return paging32_init_context(vcpu);
}
+static int init_kvm_mmu(struct kvm_vcpu *vcpu)
+{
+ if (tdp_enabled)
+ return init_kvm_tdp_mmu(vcpu);
+ else
+ return init_kvm_softmmu(vcpu);
+}
+
static void destroy_kvm_mmu(struct kvm_vcpu *vcpu)
{
ASSERT(vcpu);
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 1fce19e..e64e9f5 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -3,6 +3,12 @@
#include <linux/kvm_host.h>
+#ifdef CONFIG_X86_64
+#define TDP_ROOT_LEVEL PT64_ROOT_LEVEL
+#else
+#define TDP_ROOT_LEVEL PT32E_ROOT_LEVEL
+#endif
+
static inline void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)
{
if (unlikely(vcpu->kvm->arch.n_free_mmu_pages < KVM_MIN_FREE_MMU_PAGES))