X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-i386%2Fsegment.h;h=9f9184c6b629e19f016aa500377ee6f75c752161;hb=refs%2Fheads%2Fvserver;hp=faf995307b9e66428f06e9afd514217760c4f61a;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git

diff --git a/include/asm-i386/segment.h b/include/asm-i386/segment.h
index faf995307..9f9184c6b 100644
--- a/include/asm-i386/segment.h
+++ b/include/asm-i386/segment.h
@@ -39,7 +39,7 @@
  *  25 - APM BIOS support 
  *
  *  26 - ESPFIX small SS
- *  27 - unused
+ *  27 - PDA				[ per-cpu private data area ]
  *  28 - unused
  *  29 - unused
  *  30 - unused
@@ -74,6 +74,9 @@
 #define GDT_ENTRY_ESPFIX_SS		(GDT_ENTRY_KERNEL_BASE + 14)
 #define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS * 8)
 
+#define GDT_ENTRY_PDA			(GDT_ENTRY_KERNEL_BASE + 15)
+#define __KERNEL_PDA (GDT_ENTRY_PDA * 8)
+
 #define GDT_ENTRY_DOUBLEFAULT_TSS	31
 
 /*
@@ -83,6 +86,15 @@
 
 #define GDT_SIZE (GDT_ENTRIES * 8)
 
+/* Matches __KERNEL_CS and __USER_CS (they must be 2 entries apart) */
+#ifdef CONFIG_XEN
+#define SEGMENT_IS_FLAT_CODE(x)  ((x) == __USER_CS || (x) == (__KERNEL_CS | get_kernel_rpl()))
+#else
+#define SEGMENT_IS_FLAT_CODE(x)  (((x) & 0xec) == GDT_ENTRY_KERNEL_CS * 8)
+#endif
+/* 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 +124,22 @@
  */
 #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
+
+#ifndef CONFIG_PARAVIRT
+#ifdef CONFIG_XEN
+#define get_kernel_rpl()   (xen_feature(XENFEAT_supervisor_mode_kernel)?0:1)
+#else
+#define get_kernel_rpl()  0
+#endif /* CONFIG_XEN */
+#endif
 #endif