KVM: MIPS: Use uaccess to read/modify guest instructions

[linux.git] / arch / mips / kvm / mmu.c

diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
index 98f1a7715a688ba37228bfab2da78d1142cefc16..c4e9c65065ea792bf79ecc4feddfffe53ff5dddd 100644 (file)
--- a/arch/mips/kvm/mmu.c
+++ b/arch/mips/kvm/mmu.c
@@ -11,6 +11,7 @@
 
 #include <linux/highmem.h>
 #include <linux/kvm_host.h>
+#include <linux/uaccess.h>
 #include <asm/mmu_context.h>
 #include <asm/pgalloc.h>
 
@@ -134,34 +135,6 @@ static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
        return err;
 }
 
-/* Translate guest KSEG0 addresses to Host PA */
-unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu,
-                                                   unsigned long gva)
-{
-       gfn_t gfn;
-       unsigned long offset = gva & ~PAGE_MASK;
-       struct kvm *kvm = vcpu->kvm;
-
-       if (KVM_GUEST_KSEGX(gva) != KVM_GUEST_KSEG0) {
-               kvm_err("%s/%p: Invalid gva: %#lx\n", __func__,
-                       __builtin_return_address(0), gva);
-               return KVM_INVALID_PAGE;
-       }
-
-       gfn = (KVM_GUEST_CPHYSADDR(gva) >> PAGE_SHIFT);
-
-       if (gfn >= kvm->arch.guest_pmap_npages) {
-               kvm_err("%s: Invalid gfn: %#llx, GVA: %#lx\n", __func__, gfn,
-                       gva);
-               return KVM_INVALID_PAGE;
-       }
-
-       if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
-               return KVM_INVALID_ADDR;
-
-       return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset;
-}
-
 static pte_t *kvm_trap_emul_pte_for_gva(struct kvm_vcpu *vcpu,
                                        unsigned long addr)
 {
@@ -551,51 +524,11 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 
 u32 kvm_get_inst(u32 *opc, struct kvm_vcpu *vcpu)
 {
-       struct mips_coproc *cop0 = vcpu->arch.cop0;
-       unsigned long paddr, flags, vpn2, asid;
-       unsigned long va = (unsigned long)opc;
-       void *vaddr;
        u32 inst;
-       int index;
-
-       if (KVM_GUEST_KSEGX(va) < KVM_GUEST_KSEG0 ||
-           KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG23) {
-               local_irq_save(flags);
-               index = kvm_mips_host_tlb_lookup(vcpu, va);
-               if (index >= 0) {
-                       inst = *(opc);
-               } else {
-                       vpn2 = va & VPN2_MASK;
-                       asid = kvm_read_c0_guest_entryhi(cop0) &
-                                               KVM_ENTRYHI_ASID;
-                       index = kvm_mips_guest_tlb_lookup(vcpu, vpn2 | asid);
-                       if (index < 0) {
-                               kvm_err("%s: get_user_failed for %p, vcpu: %p, ASID: %#lx\n",
-                                       __func__, opc, vcpu, read_c0_entryhi());
-                               kvm_mips_dump_host_tlbs();
-                               kvm_mips_dump_guest_tlbs(vcpu);
-                               local_irq_restore(flags);
-                               return KVM_INVALID_INST;
-                       }
-                       if (kvm_mips_handle_mapped_seg_tlb_fault(vcpu,
-                                       &vcpu->arch.guest_tlb[index], va)) {
-                               kvm_err("%s: handling mapped seg tlb fault failed for %p, index: %u, vcpu: %p, ASID: %#lx\n",
-                                       __func__, opc, index, vcpu,
-                                       read_c0_entryhi());
-                               kvm_mips_dump_guest_tlbs(vcpu);
-                               local_irq_restore(flags);
-                               return KVM_INVALID_INST;
-                       }
-                       inst = *(opc);
-               }
-               local_irq_restore(flags);
-       } else if (KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG0) {
-               paddr = kvm_mips_translate_guest_kseg0_to_hpa(vcpu, va);
-               vaddr = kmap_atomic(pfn_to_page(PHYS_PFN(paddr)));
-               vaddr += paddr & ~PAGE_MASK;
-               inst = *(u32 *)vaddr;
-               kunmap_atomic(vaddr);
-       } else {
+       int err;
+
+       err = get_user(inst, opc);
+       if (unlikely(err)) {
                kvm_err("%s: illegal address: %p\n", __func__, opc);
                return KVM_INVALID_INST;
        }