KVM: x86: Combine the lgdt and lidt emulation logic

LGDT and LIDT emulation logic is almost identical. Merge the logic into a
single point to avoid redundancy. This will be used by the next patch that
will ensure the bases of the loaded GDTR and IDTR are canonical.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 9f960b4..c86b378 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -3327,7 +3327,7 @@ static int em_sidt(struct x86_emulate_ctxt *ctxt)
        return emulate_store_desc_ptr(ctxt, ctxt->ops->get_idt);
 }
 
-static int em_lgdt(struct x86_emulate_ctxt *ctxt)
+static int em_lgdt_lidt(struct x86_emulate_ctxt *ctxt, bool lgdt)
 {
        struct desc_ptr desc_ptr;
        int rc;
@@ -3339,12 +3339,20 @@ static int em_lgdt(struct x86_emulate_ctxt *ctxt)
                             ctxt->op_bytes);
        if (rc != X86EMUL_CONTINUE)
                return rc;
-       ctxt->ops->set_gdt(ctxt, &desc_ptr);
+       if (lgdt)
+               ctxt->ops->set_gdt(ctxt, &desc_ptr);
+       else
+               ctxt->ops->set_idt(ctxt, &desc_ptr);
        /* Disable writeback. */
        ctxt->dst.type = OP_NONE;
        return X86EMUL_CONTINUE;
 }
 
+static int em_lgdt(struct x86_emulate_ctxt *ctxt)
+{
+       return em_lgdt_lidt(ctxt, true);
+}
+
 static int em_vmmcall(struct x86_emulate_ctxt *ctxt)
 {
        int rc;
@@ -3358,20 +3366,7 @@ static int em_vmmcall(struct x86_emulate_ctxt *ctxt)
 
 static int em_lidt(struct x86_emulate_ctxt *ctxt)
 {
-       struct desc_ptr desc_ptr;
-       int rc;
-
-       if (ctxt->mode == X86EMUL_MODE_PROT64)
-               ctxt->op_bytes = 8;
-       rc = read_descriptor(ctxt, ctxt->src.addr.mem,
-                            &desc_ptr.size, &desc_ptr.address,
-                            ctxt->op_bytes);
-       if (rc != X86EMUL_CONTINUE)
-               return rc;
-       ctxt->ops->set_idt(ctxt, &desc_ptr);
-       /* Disable writeback. */
-       ctxt->dst.type = OP_NONE;
-       return X86EMUL_CONTINUE;
+       return em_lgdt_lidt(ctxt, false);
 }
 
 static int em_smsw(struct x86_emulate_ctxt *ctxt)