KVM: x86 emulator: add framework for instruction intercepts

[deliverable/linux.git] / arch / x86 / kvm / emulate.c

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 2b6c24e572d4eb681394f973e4341178789e1422..a81486790ba8a2399f27513c0558cf35e597b385 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -104,6 +104,7 @@
 
 struct opcode {
        u32 flags;
+       u8 intercept;
        union {
                int (*execute)(struct x86_emulate_ctxt *ctxt);
                struct opcode *group;
@@ -2423,10 +2424,13 @@ static int em_movdqu(struct x86_emulate_ctxt *ctxt)
 }
 
 #define D(_y) { .flags = (_y) }
+#define DI(_y, _i) { .flags = (_y), .intercept = x86_intercept_##_i }
 #define N    D(0)
 #define G(_f, _g) { .flags = ((_f) | Group), .u.group = (_g) }
 #define GD(_f, _g) { .flags = ((_f) | Group | GroupDual), .u.gdual = (_g) }
 #define I(_f, _e) { .flags = (_f), .u.execute = (_e) }
+#define II(_f, _e, _i) \
+       { .flags = (_f), .u.execute = (_e), .intercept = x86_intercept_##_i }
 #define GP(_f, _g) { .flags = ((_f) | Prefix), .u.gprefix = (_g) }
 
 #define D2bv(_f)      D((_f) | ByteOp), D(_f)
@@ -2867,6 +2871,7 @@ done_prefixes:
        }
 
        c->execute = opcode.u.execute;
+       c->intercept = opcode.intercept;
 
        /* Unrecognised? */
        if (c->d == 0 || (c->d & Undefined))
@@ -3116,12 +3121,26 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
                goto done;
        }
 
+       if (unlikely(ctxt->guest_mode) && c->intercept) {
+               rc = ops->intercept(ctxt, c->intercept,
+                                   X86_ICPT_PRE_EXCEPT);
+               if (rc != X86EMUL_CONTINUE)
+                       goto done;
+       }
+
        /* Privileged instruction can be executed only in CPL=0 */
        if ((c->d & Priv) && ops->cpl(ctxt->vcpu)) {
                rc = emulate_gp(ctxt, 0);
                goto done;
        }
 
+       if (unlikely(ctxt->guest_mode) && c->intercept) {
+               rc = ops->intercept(ctxt, c->intercept,
+                                   X86_ICPT_POST_EXCEPT);
+               if (rc != X86EMUL_CONTINUE)
+                       goto done;
+       }
+
        if (c->rep_prefix && (c->d & String)) {
                /* All REP prefixes have the same first termination condition */
                if (address_mask(c, c->regs[VCPU_REGS_RCX]) == 0) {
@@ -3160,6 +3179,13 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
 
 special_insn:
 
+       if (unlikely(ctxt->guest_mode) && c->intercept) {
+               rc = ops->intercept(ctxt, c->intercept,
+                                   X86_ICPT_POST_MEMACCESS);
+               if (rc != X86EMUL_CONTINUE)
+                       goto done;
+       }
+
        if (c->execute) {
                rc = c->execute(ctxt);
                if (rc != X86EMUL_CONTINUE)