[PATCH 3/4] ksysfs: export VMCSINFO via sysfs

[zhangyanfei]

This patch creates sysfs file to export where VMCSINFO is allocated,
as below:
        $ cat /sys/kernel/vmcsinfo
        1cb88a0 2000
number on the left-hand side is the physical address of VMCSINFO,
while the one on the right-hand side is the max size of VMCSINFO.

Signed-off-by: zhangyanfei <zhangyanfei at cn.fujitsu.com>
---
 kernel/ksysfs.c |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 4e316e1..becbb68 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -18,6 +18,8 @@
 #include <linux/stat.h>
 #include <linux/sched.h>
 #include <linux/capability.h>
+#include <asm/vmcsinfo.h>
+#include <asm/virtext.h>
 
 #define KERNEL_ATTR_RO(_name) \
 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
@@ -133,6 +135,20 @@ KERNEL_ATTR_RO(vmcoreinfo);
 
 #endif /* CONFIG_KEXEC */
 
+#ifdef CONFIG_X86
+static ssize_t vmcsinfo_show(struct kobject *kobj,
+			     struct kobj_attribute *attr, char *buf)
+{
+	if (cpu_has_vmx())
+		return sprintf(buf, "%lx %x\n",
+			       paddr_vmcsinfo_note(),
+			       (unsigned int)vmcsinfo_max_size);
+	return 0;
+}
+KERNEL_ATTR_RO(vmcsinfo);
+
+#endif /* CONFIG_X86 */
+
 /* whether file capabilities are enabled */
 static ssize_t fscaps_show(struct kobject *kobj,
 				  struct kobj_attribute *attr, char *buf)
@@ -182,6 +198,9 @@ static struct attribute * kernel_attrs[] = {
 	&kexec_crash_size_attr.attr,
 	&vmcoreinfo_attr.attr,
 #endif
+#ifdef CONFIG_X86
+	&vmcsinfo_attr.attr,
+#endif
 	NULL
 };
 
-- 
1.7.1