X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-i386%2Fsegment.h;h=9f9184c6b629e19f016aa500377ee6f75c752161;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=bb5ff5b2c02ec210510b361956fa7afd2791b62d;hpb=f7f1b0f1e2fbadeab12d24236000e778aa9b1ead;p=linux-2.6.git

diff --git a/include/asm-i386/segment.h b/include/asm-i386/segment.h
index bb5ff5b2c..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
@@ -91,6 +103,20 @@
 #define GDT_ENTRY_BOOT_DS		(GDT_ENTRY_BOOT_CS + 1)
 #define __BOOT_DS	(GDT_ENTRY_BOOT_DS * 8)
 
+/* The PnP BIOS entries in the GDT */
+#define GDT_ENTRY_PNPBIOS_CS32		(GDT_ENTRY_PNPBIOS_BASE + 0)
+#define GDT_ENTRY_PNPBIOS_CS16		(GDT_ENTRY_PNPBIOS_BASE + 1)
+#define GDT_ENTRY_PNPBIOS_DS		(GDT_ENTRY_PNPBIOS_BASE + 2)
+#define GDT_ENTRY_PNPBIOS_TS1		(GDT_ENTRY_PNPBIOS_BASE + 3)
+#define GDT_ENTRY_PNPBIOS_TS2		(GDT_ENTRY_PNPBIOS_BASE + 4)
+
+/* The PnP BIOS selectors */
+#define PNP_CS32   (GDT_ENTRY_PNPBIOS_CS32 * 8)	/* segment for calling fn */
+#define PNP_CS16   (GDT_ENTRY_PNPBIOS_CS16 * 8)	/* code segment for BIOS */
+#define PNP_DS     (GDT_ENTRY_PNPBIOS_DS * 8)	/* data segment for BIOS */
+#define PNP_TS1    (GDT_ENTRY_PNPBIOS_TS1 * 8)	/* transfer data segment */
+#define PNP_TS2    (GDT_ENTRY_PNPBIOS_TS2 * 8)	/* another data segment */
+
 /*
  * The interrupt descriptor table has room for 256 idt's,
  * the global descriptor table is dependent on the number
@@ -98,4 +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