Clean up KVM/QEMU interaction

This patch attempts to clean up the interactions between KVM and QEMU.  Sorry
for such a big patch, but I don't think there's a better way to approach this
such that it's still bisect friendly.  I think this is most of what's needed to
get basic KVM support into QEMU though.

Right now, there's a mix of #ifdef USE_KVM, if (kvm_allowed), and various
extern declarations.  It's all pretty fugly and there's a lot of mistakes due
to it.

The following patch eliminates almost all uses of #ifdef USE_KVM by introducing
a kvm_enabled() macro.  If USE_KVM is set, this macro evaluates to kvm_allowed.
If USE_KVM isn't set, the macro evaluates to 0.

Since GCC eliminates if (0) blocks, this is just as good as using #ifdef.  By
making sure that we never call into libkvm directly from QEMU, we can also just
not link qemu-kvm when USE_KVM isn't set instead of having the entire file
wrapped in a USE_KVM.

We also change the --enable-kvm configure option to --disable-kvm since KVM is
enabled by default.

I've tested this patch on x86 with 32-bit and 64-bit Linux guests and a 32-bit
Windows guest.  I've also tested with USE_KVM not set.  Jerone has also
verified that it doesn't PPC.  My apologies if it breaks ia64 but I have no
way of testing that.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

2 files changed, 6 insertions, 14 deletions

diff --git a/target-ia64/cpu.h b/target-ia64/cpu.h
index 2d91cb9bc..97358eec9 100644
--- a/target-ia64/cpu.h
+++ b/target-ia64/cpu.h
@@ -51,9 +51,7 @@ typedef struct CPUIA64State {
    int user_mode_only;
    uint32_t hflags;
 
-#ifdef USE_KVM
-      uint8_t ready_for_interrupt_injection;
-#endif
+    uint8_t ready_for_interrupt_injection;
 
 } CPUIA64State;
 
diff --git a/target-ia64/op_helper.c b/target-ia64/op_helper.c
index 5138af502..8660b17db 100644
--- a/target-ia64/op_helper.c
+++ b/target-ia64/op_helper.c
@@ -24,7 +24,7 @@
 #include "cpu.h"
 #include "exec-all.h"
 
-extern int kvm_allowed;
+#include "qemu-kvm.h"
 
 CPUState *cpu_ia64_init(char *cpu_model){
     CPUState *env;
@@ -33,14 +33,10 @@ CPUState *cpu_ia64_init(char *cpu_model){
         return NULL;
     cpu_exec_init(env);
     cpu_reset(env);
-#ifdef USE_KVM
-    {
-        if (kvm_allowed) {
-            kvm_qemu_init_env(env);
-            env->ready_for_interrupt_injection = 1;
-        }
+    if (kvm_enabled()) {
+	kvm_qemu_init_env(env);
+	env->ready_for_interrupt_injection = 1;
     }
-#endif
     return env;
 }
 
@@ -74,12 +70,10 @@ void switch_mode(CPUState *env, int mode)
 /* Handle a CPU exception.  */
 void do_interrupt(CPUIA64State *env)
 {
-#ifdef USE_KVM
-    if (kvm_allowed) {
+    if (kvm_enabled()) {
 	printf("%s: unexpect\n", __FUNCTION__);
 	exit(-1);
     }
-#endif
 }