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-rw-r--r--include/asm-i386/segment.h17
1 files changed, 17 insertions, 0 deletions
diff --git a/include/asm-i386/segment.h b/include/asm-i386/segment.h
index faf995307b9e..b7ab59685ba7 100644
--- a/include/asm-i386/segment.h
+++ b/include/asm-i386/segment.h
@@ -83,6 +83,11 @@
#define GDT_SIZE (GDT_ENTRIES * 8)
+/* Matches __KERNEL_CS and __USER_CS (they must be 2 entries apart) */
+#define SEGMENT_IS_FLAT_CODE(x) (((x) & 0xec) == GDT_ENTRY_KERNEL_CS * 8)
+/* Matches PNP_CS32 and PNP_CS16 (they must be consecutive) */
+#define SEGMENT_IS_PNP_CODE(x) (((x) & 0xf4) == GDT_ENTRY_PNPBIOS_BASE * 8)
+
/* Simple and small GDT entries for booting only */
#define GDT_ENTRY_BOOT_CS 2
@@ -112,4 +117,16 @@
*/
#define IDT_ENTRIES 256
+/* Bottom two bits of selector give the ring privilege level */
+#define SEGMENT_RPL_MASK 0x3
+/* Bit 2 is table indicator (LDT/GDT) */
+#define SEGMENT_TI_MASK 0x4
+
+/* User mode is privilege level 3 */
+#define USER_RPL 0x3
+/* LDT segment has TI set, GDT has it cleared */
+#define SEGMENT_LDT 0x4
+#define SEGMENT_GDT 0x0
+
+#define get_kernel_rpl() 0
#endif