xen64: set up syscall and sysenter entrypoints for 64-bit

We set up entrypoints for syscall and sysenter.  sysenter is only used
for 32-bit compat processes, whereas syscall can be used in by both 32
and 64-bit processes.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 39 insertions, 3 deletions

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index bea3d4f779db..9d7a14402895 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -86,9 +86,11 @@ static void xen_idle(void)
  */
 static void __init fiddle_vdso(void)
 {
+#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
         extern const char vdso32_default_start;
         u32 *mask = VDSO32_SYMBOL(&vdso32_default_start, NOTE_MASK);
         *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
+#endif
 }
 
 static __cpuinit int register_callback(unsigned type, const void *func)
@@ -106,15 +108,48 @@ void __cpuinit xen_enable_sysenter(void)
 {
         int cpu = smp_processor_id();
         extern void xen_sysenter_target(void);
+        int ret;
+
+#ifdef CONFIG_X86_32
+        if (!boot_cpu_has(X86_FEATURE_SEP)) {
+                return;
+        }
+#else
+        if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
+            boot_cpu_data.x86_vendor != X86_VENDOR_CENTAUR) {
+                return;
+        }
+#endif
 
-        if (!boot_cpu_has(X86_FEATURE_SEP) ||
-            register_callback(CALLBACKTYPE_sysenter,
-                              xen_sysenter_target) != 0) {
+        ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target);
+        if(ret != 0) {
                 clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
                 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
         }
 }
 
+void __cpuinit xen_enable_syscall(void)
+{
+#ifdef CONFIG_X86_64
+        int cpu = smp_processor_id();
+        int ret;
+        extern void xen_syscall_target(void);
+        extern void xen_syscall32_target(void);
+
+        ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target);
+        if (ret != 0) {
+                printk("failed to set syscall: %d\n", ret);
+                clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SYSCALL);
+                clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SYSCALL);
+        } else {
+                ret = register_callback(CALLBACKTYPE_syscall32,
+                                        xen_syscall32_target);
+                if (ret != 0)
+                        printk("failed to set 32-bit syscall: %d\n", ret);
+        }
+#endif /* CONFIG_X86_64 */
+}
+
 void __init xen_arch_setup(void)
 {
         struct physdev_set_iopl set_iopl;
@@ -131,6 +166,7 @@ void __init xen_arch_setup(void)
                 BUG();
 
         xen_enable_sysenter();
+        xen_enable_syscall();
 
         set_iopl.iopl = 1;
         rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);