x86-64: add symbolic constants for the boot segment selectors

Add symbolic constants for the segment selectors/GDT slots used by the setup code, for consistency with i386. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mariux64 · Jul 12, 2007 · 8afd2af · 8afd2af
1 parent 77e1dd6
commit 8afd2af
Showing 1 changed file with 8 additions and 0 deletions.
diff --git a/include/asm-x86_64/segment.h b/include/asm-x86_64/segment.h
@@ -3,6 +3,14 @@
 
 #include <asm/cache.h>
 
+/* Simple and small GDT entries for booting only */
+
+#define GDT_ENTRY_BOOT_CS		2
+#define __BOOT_CS	(GDT_ENTRY_BOOT_CS * 8)
+
+#define GDT_ENTRY_BOOT_DS		(GDT_ENTRY_BOOT_CS + 1)
+#define __BOOT_DS	(GDT_ENTRY_BOOT_DS * 8)
+
 #define __KERNEL_CS	0x10
 #define __KERNEL_DS	0x18