1 files changed, 38 insertions, 0 deletions
diff --git a/arch/um/sys-x86_64/shared/sysdep/host_ldt.h b/arch/um/sys-x86_64/shared/sysdep/host_ldt.h
new file mode 100644
index 00000000000..e8b1be1e154
--- /dev/null
+++ b/arch/um/sys-x86_64/shared/sysdep/host_ldt.h
@@ -0,0 +1,38 @@
+#ifndef __ASM_HOST_LDT_X86_64_H
+#define __ASM_HOST_LDT_X86_64_H
+
+#include <asm/ldt.h>
+
+/*
+ * macros stolen from include/asm-x86_64/desc.h
+ */
+#define LDT_entry_a(info) \
+	((((info)->base_addr & 0x0000ffff) << 16) | ((info)->limit & 0x0ffff))
+
+/* Don't allow setting of the lm bit. It is useless anyways because
+ * 64bit system calls require __USER_CS. */
+#define LDT_entry_b(info) \
+	(((info)->base_addr & 0xff000000) | \
+	(((info)->base_addr & 0x00ff0000) >> 16) | \
+	((info)->limit & 0xf0000) | \
+	(((info)->read_exec_only ^ 1) << 9) | \
+	((info)->contents << 10) | \
+	(((info)->seg_not_present ^ 1) << 15) | \
+	((info)->seg_32bit << 22) | \
+	((info)->limit_in_pages << 23) | \
+	((info)->useable << 20) | \
+	/* ((info)->lm << 21) | */ \
+	0x7000)
+
+#define LDT_empty(info) (\
+	(info)->base_addr	== 0	&& \
+	(info)->limit		== 0	&& \
+	(info)->contents	== 0	&& \
+	(info)->read_exec_only	== 1	&& \
+	(info)->seg_32bit	== 0	&& \
+	(info)->limit_in_pages	== 0	&& \
+	(info)->seg_not_present	== 1	&& \
+	(info)->useable		== 0	&& \
+	(info)->lm              == 0)
+
+#endif