Commit f910d134 authored by H. Peter Anvin's avatar H. Peter Anvin
Browse files

x86: unify and correct the GDT_ENTRY() macro 



Impact: None (cleanup only)

Merge the GDT_ENTRY() macro between arch/x86/boot/pm.c and
arch/x86/kernel/acpi/sleep.c and put the new one in
<asm-x86/segment.h>.

While we're at it, correct the bitmasks for the limit and flags.  The
new version relies on using ULL constants in order to cause type
promotion rather than explicit casts; this avoids having to include
<linux/types.h> in <asm-x86/segments.h>.

Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
parent 5b664cb2

arch/x86/boot/pm.c

+0 −6
Original line number Diff line number Diff line
@@ -98,12 +98,6 @@ static void reset_coprocessor(void) 
/*

 * Set up the GDT

 */

#define GDT_ENTRY(flags, base, limit)		\

	(((u64)(base & 0xff000000) << 32) |	\

	 ((u64)flags << 40) |			\

	 ((u64)(limit & 0x00ff0000) << 32) |	\

	 ((u64)(base & 0x00ffffff) << 16) |	\

	 ((u64)(limit & 0x0000ffff)))



struct gdt_ptr {

	u16 len;

arch/x86/kernel/acpi/sleep.c

+1 −9
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
#include <linux/bootmem.h>

#include <linux/dmi.h>

#include <linux/cpumask.h>

#include <asm/segment.h>



#include "realmode/wakeup.h"

#include "sleep.h"
@@ -23,15 +24,6 @@ static unsigned long acpi_realmode; 
static char temp_stack[10240];

#endif



/* XXX: this macro should move to asm-x86/segment.h and be shared with the

   boot code... */

#define GDT_ENTRY(flags, base, limit)		\

	(((u64)(base & 0xff000000) << 32) |	\

	 ((u64)flags << 40) |			\

	 ((u64)(limit & 0x00ff0000) << 32) |	\

	 ((u64)(base & 0x00ffffff) << 16) |	\

	 ((u64)(limit & 0x0000ffff)))



/**

 * acpi_save_state_mem - save kernel state

 *

include/asm-x86/segment.h

+9 −0
Original line number Diff line number Diff line 
#ifndef _ASM_X86_SEGMENT_H_

#define _ASM_X86_SEGMENT_H_



/* Constructor for a conventional segment GDT (or LDT) entry */

/* This is a macro so it can be used in initializers */

#define GDT_ENTRY(flags, base, limit)			\

	((((base)  & 0xff000000ULL) << (56-24)) |	\

	 (((flags) & 0x0000f0ffULL) << 40) |		\

	 (((limit) & 0x000f0000ULL) << (48-16)) |	\

	 (((base)  & 0x00ffffffULL) << 16) |		\

	 (((limit) & 0x0000ffffULL)))



/* Simple and small GDT entries for booting only */



#define GDT_ENTRY_BOOT_CS	2

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