KVM: Portability: Move x86 instruction emulation code to x86.c

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 175 insertions, 0 deletions

diff --git a/drivers/kvm/x86.c b/drivers/kvm/x86.c
index c1f10e58f4d2..2cf7ebab50f4 100644
--- a/drivers/kvm/x86.c
+++ b/drivers/kvm/x86.c
@@ -1610,3 +1610,178 @@ __init void kvm_arch_init(void)
 {
         kvm_init_msr_list();
 }
+
+int kvm_emulate_halt(struct kvm_vcpu *vcpu)
+{
+        ++vcpu->stat.halt_exits;
+        if (irqchip_in_kernel(vcpu->kvm)) {
+                vcpu->mp_state = VCPU_MP_STATE_HALTED;
+                kvm_vcpu_block(vcpu);
+                if (vcpu->mp_state != VCPU_MP_STATE_RUNNABLE)
+                        return -EINTR;
+                return 1;
+        } else {
+                vcpu->run->exit_reason = KVM_EXIT_HLT;
+                return 0;
+        }
+}
+EXPORT_SYMBOL_GPL(kvm_emulate_halt);
+
+int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
+{
+        unsigned long nr, a0, a1, a2, a3, ret;
+
+        kvm_x86_ops->cache_regs(vcpu);
+
+        nr = vcpu->regs[VCPU_REGS_RAX];
+        a0 = vcpu->regs[VCPU_REGS_RBX];
+        a1 = vcpu->regs[VCPU_REGS_RCX];
+        a2 = vcpu->regs[VCPU_REGS_RDX];
+        a3 = vcpu->regs[VCPU_REGS_RSI];
+
+        if (!is_long_mode(vcpu)) {
+                nr &= 0xFFFFFFFF;
+                a0 &= 0xFFFFFFFF;
+                a1 &= 0xFFFFFFFF;
+                a2 &= 0xFFFFFFFF;
+                a3 &= 0xFFFFFFFF;
+        }
+
+        switch (nr) {
+        default:
+                ret = -KVM_ENOSYS;
+                break;
+        }
+        vcpu->regs[VCPU_REGS_RAX] = ret;
+        kvm_x86_ops->decache_regs(vcpu);
+        return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_emulate_hypercall);
+
+int kvm_fix_hypercall(struct kvm_vcpu *vcpu)
+{
+        char instruction[3];
+        int ret = 0;
+
+        mutex_lock(&vcpu->kvm->lock);
+
+        /*
+         * Blow out the MMU to ensure that no other VCPU has an active mapping
+         * to ensure that the updated hypercall appears atomically across all
+         * VCPUs.
+         */
+        kvm_mmu_zap_all(vcpu->kvm);
+
+        kvm_x86_ops->cache_regs(vcpu);
+        kvm_x86_ops->patch_hypercall(vcpu, instruction);
+        if (emulator_write_emulated(vcpu->rip, instruction, 3, vcpu)
+            != X86EMUL_CONTINUE)
+                ret = -EFAULT;
+
+        mutex_unlock(&vcpu->kvm->lock);
+
+        return ret;
+}
+
+static u64 mk_cr_64(u64 curr_cr, u32 new_val)
+{
+        return (curr_cr & ~((1ULL << 32) - 1)) | new_val;
+}
+
+void realmode_lgdt(struct kvm_vcpu *vcpu, u16 limit, unsigned long base)
+{
+        struct descriptor_table dt = { limit, base };
+
+        kvm_x86_ops->set_gdt(vcpu, &dt);
+}
+
+void realmode_lidt(struct kvm_vcpu *vcpu, u16 limit, unsigned long base)
+{
+        struct descriptor_table dt = { limit, base };
+
+        kvm_x86_ops->set_idt(vcpu, &dt);
+}
+
+void realmode_lmsw(struct kvm_vcpu *vcpu, unsigned long msw,
+                   unsigned long *rflags)
+{
+        lmsw(vcpu, msw);
+        *rflags = kvm_x86_ops->get_rflags(vcpu);
+}
+
+unsigned long realmode_get_cr(struct kvm_vcpu *vcpu, int cr)
+{
+        kvm_x86_ops->decache_cr4_guest_bits(vcpu);
+        switch (cr) {
+        case 0:
+                return vcpu->cr0;
+        case 2:
+                return vcpu->cr2;
+        case 3:
+                return vcpu->cr3;
+        case 4:
+                return vcpu->cr4;
+        default:
+                vcpu_printf(vcpu, "%s: unexpected cr %u\n", __FUNCTION__, cr);
+                return 0;
+        }
+}
+
+void realmode_set_cr(struct kvm_vcpu *vcpu, int cr, unsigned long val,
+                     unsigned long *rflags)
+{
+        switch (cr) {
+        case 0:
+                set_cr0(vcpu, mk_cr_64(vcpu->cr0, val));
+                *rflags = kvm_x86_ops->get_rflags(vcpu);
+                break;
+        case 2:
+                vcpu->cr2 = val;
+                break;
+        case 3:
+                set_cr3(vcpu, val);
+                break;
+        case 4:
+                set_cr4(vcpu, mk_cr_64(vcpu->cr4, val));
+                break;
+        default:
+                vcpu_printf(vcpu, "%s: unexpected cr %u\n", __FUNCTION__, cr);
+        }
+}
+
+void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
+{
+        int i;
+        u32 function;
+        struct kvm_cpuid_entry *e, *best;
+
+        kvm_x86_ops->cache_regs(vcpu);
+        function = vcpu->regs[VCPU_REGS_RAX];
+        vcpu->regs[VCPU_REGS_RAX] = 0;
+        vcpu->regs[VCPU_REGS_RBX] = 0;
+        vcpu->regs[VCPU_REGS_RCX] = 0;
+        vcpu->regs[VCPU_REGS_RDX] = 0;
+        best = NULL;
+        for (i = 0; i < vcpu->cpuid_nent; ++i) {
+                e = &vcpu->cpuid_entries[i];
+                if (e->function == function) {
+                        best = e;
+                        break;
+                }
+                /*
+                 * Both basic or both extended?
+                 */
+                if (((e->function ^ function) & 0x80000000) == 0)
+                        if (!best || e->function > best->function)
+                                best = e;
+        }
+        if (best) {
+                vcpu->regs[VCPU_REGS_RAX] = best->eax;
+                vcpu->regs[VCPU_REGS_RBX] = best->ebx;
+                vcpu->regs[VCPU_REGS_RCX] = best->ecx;
+                vcpu->regs[VCPU_REGS_RDX] = best->edx;
+        }
+        kvm_x86_ops->decache_regs(vcpu);
+        kvm_x86_ops->skip_emulated_instruction(vcpu);
+}
+EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);