1 files changed, 53 insertions, 22 deletions

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 0d7d6a1b172f..37c5f7261142 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -1,8 +1,58 @@
 #ifndef LINUX_KEXEC_H
 #define LINUX_KEXEC_H
 
-#ifdef CONFIG_KEXEC
+/* kexec system call -  It loads the new kernel to boot into.
+ * kexec does not sync, or unmount filesystems so if you need
+ * that to happen you need to do that yourself.
+ */
+
 #include <linux/types.h>
+
+/* kexec flags for different usage scenarios */
+#define KEXEC_ON_CRASH          0x00000001
+#define KEXEC_PRESERVE_CONTEXT  0x00000002
+#define KEXEC_ARCH_MASK         0xffff0000
+
+/* These values match the ELF architecture values.
+ * Unless there is a good reason that should continue to be the case.
+ */
+#define KEXEC_ARCH_DEFAULT ( 0 << 16)
+#define KEXEC_ARCH_386     ( 3 << 16)
+#define KEXEC_ARCH_X86_64  (62 << 16)
+#define KEXEC_ARCH_PPC     (20 << 16)
+#define KEXEC_ARCH_PPC64   (21 << 16)
+#define KEXEC_ARCH_IA_64   (50 << 16)
+#define KEXEC_ARCH_ARM     (40 << 16)
+#define KEXEC_ARCH_S390    (22 << 16)
+#define KEXEC_ARCH_SH      (42 << 16)
+#define KEXEC_ARCH_MIPS_LE (10 << 16)
+#define KEXEC_ARCH_MIPS    ( 8 << 16)
+
+/* The artificial cap on the number of segments passed to kexec_load. */
+#define KEXEC_SEGMENT_MAX 16
+
+#ifndef __KERNEL__
+/*
+ * This structure is used to hold the arguments that are used when
+ * loading  kernel binaries.
+ */
+struct kexec_segment {
+        const void *buf;
+        size_t bufsz;
+        const void *mem;
+        size_t memsz;
+};
+
+/* Load a new kernel image as described by the kexec_segment array
+ * consisting of passed number of segments at the entry-point address.
+ * The flags allow different useage types.
+ */
+extern int kexec_load(void *, size_t, struct kexec_segment *,
+                unsigned long int);
+#endif /* __KERNEL__ */
+
+#ifdef __KERNEL__
+#ifdef CONFIG_KEXEC
 #include <linux/list.h>
 #include <linux/linkage.h>
 #include <linux/compat.h>
@@ -67,11 +117,10 @@ typedef unsigned long kimage_entry_t;
 #define IND_DONE         0x4
 #define IND_SOURCE       0x8
 
-#define KEXEC_SEGMENT_MAX 16
 struct kexec_segment {
         void __user *buf;
         size_t bufsz;
-        unsigned long mem;      /* User space sees this as a (void *) ... */
+        unsigned long mem;
         size_t memsz;
 };
 
@@ -175,25 +224,6 @@ extern struct kimage *kexec_crash_image;
 #define kexec_flush_icache_page(page)
 #endif
 
-#define KEXEC_ON_CRASH          0x00000001
-#define KEXEC_PRESERVE_CONTEXT  0x00000002
-#define KEXEC_ARCH_MASK         0xffff0000
-
-/* These values match the ELF architecture values.
- * Unless there is a good reason that should continue to be the case.
- */
-#define KEXEC_ARCH_DEFAULT ( 0 << 16)
-#define KEXEC_ARCH_386     ( 3 << 16)
-#define KEXEC_ARCH_X86_64  (62 << 16)
-#define KEXEC_ARCH_PPC     (20 << 16)
-#define KEXEC_ARCH_PPC64   (21 << 16)
-#define KEXEC_ARCH_IA_64   (50 << 16)
-#define KEXEC_ARCH_ARM     (40 << 16)
-#define KEXEC_ARCH_S390    (22 << 16)
-#define KEXEC_ARCH_SH      (42 << 16)
-#define KEXEC_ARCH_MIPS_LE (10 << 16)
-#define KEXEC_ARCH_MIPS    ( 8 << 16)
-
 /* List of defined/legal kexec flags */
 #ifndef CONFIG_KEXEC_JUMP
 #define KEXEC_FLAGS    KEXEC_ON_CRASH
@@ -228,4 +258,5 @@ struct task_struct;
 static inline void crash_kexec(struct pt_regs *regs) { }
 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 #endif /* CONFIG_KEXEC */
+#endif /* __KERNEL__ */
 #endif /* LINUX_KEXEC_H */