[Qemu-devel] [PATCH 27/32] arch-specific hooks for accelerator

[Glauber Costa <glommer@redhat.com>]

This patch provides an arch field in QEMUAccel. It will
be used initially for x86, to replace kqemu code in op_helper.c
We start with get_msr and set_msr functions, that allow accelerators
to handle non-default msrs.

Signed-off-by: Glauber Costa <glommer@redhat.com>
---
 accel.h                 |    1 +
 exec-all.h              |    2 --
 kqemu.c                 |   26 +++++++++++++++++++++++++-
 target-i386/accel86.h   |   28 ++++++++++++++++++++++++++++
 target-i386/op_helper.c |   14 +++-----------
 5 files changed, 57 insertions(+), 14 deletions(-)
 create mode 100644 target-i386/accel86.h

diff --git a/accel.h b/accel.h
index 1741f06..00a495c 100644
--- a/accel.h
+++ b/accel.h
@@ -23,6 +23,7 @@ typedef struct QEMUAccel {
     void (*trace_io)(CPUState *env);
     int (*break_loop)(CPUState *env);
     int (*cpu_exec)(CPUState *env);
+    void *arch; /* arch-specific accel functions */
 } QEMUAccel;
 
 typedef struct QEMUCont {
diff --git a/exec-all.h b/exec-all.h
index 8228746..1e9aa5a 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -369,8 +369,6 @@ void kqemu_set_phys_mem(uint64_t start_addr, ram_addr_t size,
                         ram_addr_t phys_offset);
 void kqemu_record_dump(void);
 
-extern uint32_t kqemu_comm_base;
-
 static inline int kqemu_is_ok(CPUState *env)
 {
     return(env->kqemu_enabled &&
diff --git a/kqemu.c b/kqemu.c
index 310a1af..cab6354 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -55,7 +55,7 @@ static int kqemu_state;
 #include <unistd.h>
 #include <fcntl.h>
 #include "kqemu.h"
-#include "accel.h"
+#include "accel86.h"
 
 #ifdef CONFIG_PROFILER
 #include "qemu-timer.h" /* for ticks_per_sec */
@@ -1169,6 +1169,28 @@ static CPUState *kqemu_get_env(void)
     return &kenv->env;
 }
 
+static int kqemu_get_msr(int msr, uint64_t *val)
+{
+    int ret = -1;
+    switch (msr) {
+    case MSR_QPI_COMMBASE:
+        val = kqemu_comm_base;
+        ret = 0;
+        break;
+    }
+    return ret;
+}
+
+static int kqemu_set_msr(int msr, target_ulong val)
+{
+    return -1;
+}
+
+QEMUAccel86 kqemu_accel86 = {
+    .get_msr = kqemu_get_msr,
+    .set_msr = kqemu_set_msr,
+};
+
 QEMUAccel kqemu_accel = {
     .name = "KQEMU",
     .cpu_interrupt = kqemu_cpu_interrupt,
@@ -1191,6 +1213,7 @@ QEMUAccel kqemu_accel = {
     .trace_io = kqemu_trace_io,
     .break_loop = kqemu_break_loop,
     .cpu_exec = kqemu_cpu_exec,
+    .arch = &kqemu_accel86,
 };
 
 QEMUAccel kqemu_kernel_accel = {
@@ -1212,6 +1235,7 @@ QEMUAccel kqemu_kernel_accel = {
     .trace_io = kqemu_trace_io,
     .break_loop = kqemu_break_loop,
     .cpu_exec = kqemu_cpu_exec,
+    .arch = &kqemu_accel86,
 };
 
 #endif
diff --git a/target-i386/accel86.h b/target-i386/accel86.h
new file mode 100644
index 0000000..142d63e
--- /dev/null
+++ b/target-i386/accel86.h
@@ -0,0 +1,28 @@
+#ifndef _ACCEL_86_H_
+#define _ACCEL_86_H_
+
+#include "accel.h"
+
+typedef struct QEMUAccel86 {
+	int (*get_msr)(int msr, uint64_t *value);
+	int (*set_msr)(int msr, uint64_t value);
+} QEMUAccel86;
+
+#define accel86_call_func ((QEMUAccel86 *)(current_accel->arch))
+
+static inline int accel_get_msr(int msr, uint64_t *value)
+{
+    if (!current_accel->arch)
+        return -1;
+    return accel86_call_func->get_msr(msr, value);
+}
+
+static inline int accel_set_msr(int msr, uint64_t value)
+{
+    if (!current_accel->arch)
+        return -1;
+    return accel86_call_func->set_msr(msr, value);
+}
+
+#endif
+
diff --git a/target-i386/op_helper.c b/target-i386/op_helper.c
index ebb5824..fe8ddf8 100644
--- a/target-i386/op_helper.c
+++ b/target-i386/op_helper.c
@@ -20,6 +20,7 @@
 #define CPU_NO_GLOBAL_REGS
 #include "exec.h"
 #include "host-utils.h"
+#include "accel86.h"
 
 //#define DEBUG_PCALL
 
@@ -3262,18 +3263,9 @@ void helper_rdmsr(void)
         val = env->kernelgsbase;
         break;
 #endif
-#ifdef USE_KQEMU
-    case MSR_QPI_COMMBASE:
-        if (env->kqemu_enabled) {
-            val = kqemu_comm_base;
-        } else {
-            val = 0;
-        }
-        break;
-#endif
     default:
-        /* XXX: exception ? */
-        val = 0;
+        if (accel_get_msr((uint32_t)ECX, &val) < 0)
+            val = 0;
         break;
     }
     EAX = (uint32_t)(val);
-- 
1.5.5.1