1/*
  2 * Copyright 2004-2010 Analog Devices Inc.
  3 *
  4 * Licensed under the GPL-2 or later.
  5 */
  6
  7#ifndef _ASM_THREAD_INFO_H
  8#define _ASM_THREAD_INFO_H
  9
 10#include <asm/page.h>
 11#include <asm/entry.h>
 12#include <asm/l1layout.h>
 13#include <linux/compiler.h>
 14
 15#ifdef __KERNEL__
 16
 17/* Thread Align Mask to reach to the top of the stack
 18 * for any process
 19 */
 20#define ALIGN_PAGE_MASK		0xffffe000
 21
 22/*
 23 * Size of kernel stack for each process. This must be a power of 2...
 24 */
 25#define THREAD_SIZE_ORDER	1
 26#define THREAD_SIZE		8192	/* 2 pages */
 27#define STACK_WARN		(THREAD_SIZE/8)
 28
 29#ifndef __ASSEMBLY__
 30
 31typedef unsigned long mm_segment_t;
 32
 33/*
 34 * low level task data.
 35 * If you change this, change the TI_* offsets below to match.
 36 */
 37
 38struct thread_info {
 39	struct task_struct *task;	/* main task structure */
 40	unsigned long flags;	/* low level flags */
 41	int cpu;		/* cpu we're on */
 42	int preempt_count;	/* 0 => preemptable, <0 => BUG */
 43	mm_segment_t addr_limit;	/* address limit */
 44#ifndef CONFIG_SMP
 45	struct l1_scratch_task_info l1_task_info;
 46#endif
 47};
 48
 49/*
 50 * macros/functions for gaining access to the thread information structure
 51 */
 52#define INIT_THREAD_INFO(tsk)			\
 53{						\
 54	.task		= &tsk,			\
 55	.flags		= 0,			\
 56	.cpu		= 0,			\
 57	.preempt_count	= INIT_PREEMPT_COUNT,	\
 58}
 59#define init_thread_info	(init_thread_union.thread_info)
 60#define init_stack		(init_thread_union.stack)
 61
 62/* Given a task stack pointer, you can find its corresponding
 63 * thread_info structure just by masking it to the THREAD_SIZE
 64 * boundary (currently 8K as you can see above).
 65 */
 66__attribute_const__
 67static inline struct thread_info *current_thread_info(void)
 68{
 69	struct thread_info *ti;
 70	__asm__("%0 = sp;" : "=da"(ti));
 71	return (struct thread_info *)((long)ti & ~((long)THREAD_SIZE-1));
 72}
 73
 74#endif				/* __ASSEMBLY__ */
 75
 76/*
 77 * thread information flag bit numbers
 78 */
 79#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
 80#define TIF_SIGPENDING		1	/* signal pending */
 81#define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 82#define TIF_MEMDIE		4	/* is terminating due to OOM killer */
 83#define TIF_RESTORE_SIGMASK	5	/* restore signal mask in do_signal() */
 84#define TIF_IRQ_SYNC		7	/* sync pipeline stage */
 85#define TIF_NOTIFY_RESUME	8	/* callback before returning to user */
 86#define TIF_SINGLESTEP		9
 87
 88/* as above, but as bit values */
 89#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 90#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 91#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 92#define _TIF_IRQ_SYNC		(1<<TIF_IRQ_SYNC)
 93#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
 94#define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
 95
 96#define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 97
 98#endif				/* __KERNEL__ */
 99
100#endif				/* _ASM_THREAD_INFO_H */