[PATCH] x86 emulator: Add call near absolute (opcode 0xff rm/2)

[Mohammed Gamal]

This adds the near call with absolute address instruction.

Signed-off-by: Mohammed Gamal <[EMAIL PROTECTED]>
---
 arch/x86/kvm/x86_emulate.c |   55 +++++++++++++++++++++++++++++--------------
 1 files changed, 37 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c
index b97e80e..1707056 100644
--- a/arch/x86/kvm/x86_emulate.c
+++ b/arch/x86/kvm/x86_emulate.c
@@ -1080,6 +1080,37 @@ static inline void emulate_push(struct x86_emulate_ctxt 
*ctxt)
                                               c->regs[VCPU_REGS_RSP]);
 }
 
+static int emulate_near_call(struct x86_emulate_ctxt *ctxt,
+                        struct x86_emulate_ops *ops,
+                        bool absolute)
+{
+       struct decode_cache *c = &ctxt->decode;
+       long int offset;
+       int rc = 0;
+
+       switch (c->op_bytes) {
+       case 2:
+               offset = insn_fetch(s16, 2, c->eip);
+               break;
+       case 4:
+               offset = insn_fetch(s32, 4, c->eip);
+               break;
+       default:
+               DPRINTF("Call: Invalid op_bytes\n");
+               rc = 1;
+               goto done;
+       }
+       c->src.val = (unsigned long) c->eip;
+       if (absolute)
+               c->eip = offset;
+       else
+               jmp_rel(c, offset);
+       c->op_bytes = c->ad_bytes;
+       emulate_push(ctxt);
+done:
+       return rc;
+}
+
 static inline int emulate_grp1a(struct x86_emulate_ctxt *ctxt,
                                struct x86_emulate_ops *ops)
 {
@@ -1162,6 +1193,8 @@ static inline int emulate_grp45(struct x86_emulate_ctxt 
*ctxt,
        case 1: /* dec */
                emulate_1op("dec", c->dst, ctxt->eflags);
                break;
+       case 2: /* call near abs */
+               return emulate_near_call(ctxt, ops, 1);
        case 4: /* jmp abs */
                c->eip = c->src.val;
                break;
@@ -1710,25 +1743,11 @@ special_insn:
                port = insn_fetch(u8, 1, c->eip);
                io_direction = 0;
                goto do_io;
-       case 0xe8: /* call (near) */ {
-               long int rel;
-               switch (c->op_bytes) {
-               case 2:
-                       rel = insn_fetch(s16, 2, c->eip);
-                       break;
-               case 4:
-                       rel = insn_fetch(s32, 4, c->eip);
-                       break;
-               default:
-                       DPRINTF("Call: Invalid op_bytes\n");
-                       goto cannot_emulate;
-               }
-               c->src.val = (unsigned long) c->eip;
-               jmp_rel(c, rel);
-               c->op_bytes = c->ad_bytes;
-               emulate_push(ctxt);
+       case 0xe8: /* call (near) */
+               rc = emulate_near_call(ctxt, ops, 0);
+               if (rc != 0)
+                       goto done;
                break;
-       }
        case 0xe9: /* jmp rel */
                goto jmp;
        case 0xea: /* jmp far */ {
-- 
1.5.4.3


--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html