include/asm-x86/processor_64.h

/*
 * Copyright (C) 1994 Linus Torvalds
 */

#ifndef __ASM_X86_64_PROCESSOR_H
#define __ASM_X86_64_PROCESSOR_H

#include <asm/segment.h>
#include <asm/page.h>
#include <asm/types.h>
#include <asm/sigcontext.h>
#include <asm/cpufeature.h>
#include <linux/threads.h>
#include <asm/msr.h>
#include <asm/current.h>
#include <asm/system.h>
#include <linux/personality.h>
#include <asm/desc_defs.h>

/*
 * User space process size. 47bits minus one guard page.
 */
#define TASK_SIZE64	(0x800000000000UL - 4096)

/* This decides where the kernel will search for a free chunk of vm
 * space during mmap's.
 */
#define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? 0xc0000000 : 0xFFFFe000)

#define TASK_SIZE 		(test_thread_flag(TIF_IA32) ? IA32_PAGE_OFFSET : TASK_SIZE64)
#define TASK_SIZE_OF(child) 	((test_tsk_thread_flag(child, TIF_IA32)) ? IA32_PAGE_OFFSET : TASK_SIZE64)



DECLARE_PER_CPU(struct orig_ist, orig_ist);

#define INIT_THREAD  { \
	.sp0 = (unsigned long)&init_stack + sizeof(init_stack) \
}

#define INIT_TSS  { \
	.x86_tss.sp0 = (unsigned long)&init_stack + sizeof(init_stack) \
}

#define start_thread(regs,new_rip,new_rsp) do { \
	asm volatile("movl %0,%%fs; movl %0,%%es; movl %0,%%ds": :"r" (0));	 \
	load_gs_index(0);							\
	(regs)->ip = (new_rip);						 \
	(regs)->sp = (new_rsp);						 \
	write_pda(oldrsp, (new_rsp));						 \
	(regs)->cs = __USER_CS;							 \
	(regs)->ss = __USER_DS;							 \
	(regs)->flags = 0x200;							 \
	set_fs(USER_DS);							 \
} while(0) 

/*
 * Return saved PC of a blocked thread.
 * What is this good for? it will be always the scheduler or ret_from_fork.
 */
#define thread_saved_pc(t) (*(unsigned long *)((t)->thread.sp - 8))

#define task_pt_regs(tsk) ((struct pt_regs *)(tsk)->thread.sp0 - 1)
#define KSTK_ESP(tsk) -1 /* sorry. doesn't work for syscall. */

#endif /* __ASM_X86_64_PROCESSOR_H */