[PATCH 13/22] KVM: X86: Add kvm_read_guest_page_tdp function

Joerg Roedel
2010-04-27T10:38:53Z

This patch adds a function which can read from the guests
physical memory or from the guest's guest physical memory.
This will be used in the two-dimensional page table walker.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
arch/x86/include/asm/kvm_host.h | 3 +++
arch/x86/kvm/x86.c | 24 ++++++++++++++++++++++++
2 files changed, 27 insertions(+), 0 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 3cbfb51..7851bbc 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -635,6 +635,9 @@ void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr);
void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code);
void kvm_inject_page_fault(struct kvm_vcpu *vcpu, unsigned long cr2,
u32 error_code);
+int kvm_read_guest_page_tdp(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
+ gfn_t gfn, void *data, int offset, int len,
+ u32 *error);
bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl);

int kvm_pic_set_irq(void *opaque, int irq, int level);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6b2ce1d..558d995 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -356,6 +356,30 @@ bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl)
EXPORT_SYMBOL_GPL(kvm_require_cpl);

/*
+ * This function will be used to read from the physical memory of the currently
+ * running guest. The difference to kvm_read_guest_page ist that this function
+ * can read from guest physical or from the guest's guest physical memory.
+ */
+int kvm_read_guest_page_tdp(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
+ gfn_t gfn, void *data, int offset, int len,
+ u32 *error)
+{
+ gfn_t real_gfn;
+ gpa_t gpa;
+
+ *error = 0;
+ gpa = gfn << PAGE_SHIFT;
+ real_gfn = mmu->translate_gpa(vcpu, gpa, error);
+ if (real_gfn == UNMAPPED_GVA)
+ return -EFAULT;
+
+ real_gfn >>= PAGE_SHIFT;
+
+ return kvm_read_guest_page(vcpu->kvm, real_gfn, data, offset, len);
+}
+EXPORT_SYMBOL_GPL(kvm_read_guest_page_tdp);
+
+/*
* Load the pae pdptrs. Return true is they are all valid.
*/
int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3)
--
1.7.0.4