[net-next-2.6.git] / include / asm-i386 / thread_info.h

/* thread_info.h: i386 low-level thread information
 *
 * Copyright (C) 2002  David Howells (dhowells@redhat.com)
 * - Incorporating suggestions made by Linus Torvalds and Dave Miller
 */

#ifndef _ASM_THREAD_INFO_H
#define _ASM_THREAD_INFO_H

#ifdef __KERNEL__

#include <linux/compiler.h>
#include <asm/page.h>

#ifndef __ASSEMBLY__
#include <asm/processor.h>
#endif

/*
 * low level task data that entry.S needs immediate access to
 * - this struct should fit entirely inside of one cache line
 * - this struct shares the supervisor stack pages
 * - if the contents of this structure are changed, the assembly constants must also be changed
 */
#ifndef __ASSEMBLY__

struct thread_info {
	struct task_struct	*task;		/* main task structure */
	struct exec_domain	*exec_domain;	/* execution domain */
	unsigned long		flags;		/* low level flags */
	unsigned long		status;		/* thread-synchronous flags */
	__u32			cpu;		/* current CPU */
	int			preempt_count;	/* 0 => preemptable, <0 => BUG */


	mm_segment_t		addr_limit;	/* thread address space:
					 	   0-0xBFFFFFFF for user-thead
						   0-0xFFFFFFFF for kernel-thread
						*/
	void			*sysenter_return;
	struct restart_block    restart_block;

	unsigned long           previous_esp;   /* ESP of the previous stack in case
						   of nested (IRQ) stacks
						*/
	__u8			supervisor_stack[0];
};

#else /* !__ASSEMBLY__ */

#include <asm/asm-offsets.h>

#endif

#define PREEMPT_ACTIVE		0x10000000
#ifdef CONFIG_4KSTACKS
#define THREAD_SIZE            (4096)
#else
#define THREAD_SIZE		(8192)
#endif

#define STACK_WARN             (THREAD_SIZE/8)
/*
 * macros/functions for gaining access to the thread information structure
 *
 * preempt_count needs to be 1 initially, until the scheduler is functional.
 */
#ifndef __ASSEMBLY__

#define INIT_THREAD_INFO(tsk)			\
{						\
	.task		= &tsk,			\
	.exec_domain	= &default_exec_domain,	\
	.flags		= 0,			\
	.cpu		= 0,			\
	.preempt_count	= 1,			\
	.addr_limit	= KERNEL_DS,		\
	.restart_block = {			\
		.fn = do_no_restart_syscall,	\
	},					\
}

#define init_thread_info	(init_thread_union.thread_info)
#define init_stack		(init_thread_union.stack)


/* how to get the current stack pointer from C */
register unsigned long current_stack_pointer asm("esp") __attribute_used__;

/* how to get the thread information struct from C */
static inline struct thread_info *current_thread_info(void)
{
	return (struct thread_info *)(current_stack_pointer & ~(THREAD_SIZE - 1));
}

/* thread information allocation */
#ifdef CONFIG_DEBUG_STACK_USAGE
#define alloc_thread_info(tsk) ((struct thread_info *) \
	__get_free_pages(GFP_KERNEL| __GFP_ZERO, get_order(THREAD_SIZE)))
#else
#define alloc_thread_info(tsk) ((struct thread_info *) \
	__get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE)))
#endif

#define free_thread_info(info)	free_pages((unsigned long)(info), get_order(THREAD_SIZE))

#else /* !__ASSEMBLY__ */

/* how to get the thread information struct from ASM */
#define GET_THREAD_INFO(reg) \
	movl $-THREAD_SIZE, reg; \
	andl %esp, reg

/* use this one if reg already contains %esp */
#define GET_THREAD_INFO_WITH_ESP(reg) \
	andl $-THREAD_SIZE, reg

#endif

/*
 * thread information flags
 * - these are process state flags that various assembly files may need to access
 * - pending work-to-be-done flags are in LSW
 * - other flags in MSW
 */
#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
#define TIF_SIGPENDING		1	/* signal pending */
#define TIF_NEED_RESCHED	2	/* rescheduling necessary */
#define TIF_SINGLESTEP		3	/* restore singlestep on return to user mode */
#define TIF_IRET		4	/* return with iret */
#define TIF_SYSCALL_EMU		5	/* syscall emulation active */
#define TIF_SYSCALL_AUDIT	6	/* syscall auditing active */
#define TIF_SECCOMP		7	/* secure computing */
#define TIF_RESTORE_SIGMASK	8	/* restore signal mask in do_signal() */
#define TIF_MEMDIE		16
#define TIF_DEBUG		17	/* uses debug registers */
#define TIF_IO_BITMAP		18	/* uses I/O bitmap */
#define TIF_FREEZE		19	/* is freezing for suspend */
#define TIF_NOTSC		20	/* TSC is not accessible in userland */

#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
#define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
#define _TIF_IRET		(1<<TIF_IRET)
#define _TIF_SYSCALL_EMU	(1<<TIF_SYSCALL_EMU)
#define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
#define _TIF_SECCOMP		(1<<TIF_SECCOMP)
#define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
#define _TIF_DEBUG		(1<<TIF_DEBUG)
#define _TIF_IO_BITMAP		(1<<TIF_IO_BITMAP)
#define _TIF_FREEZE		(1<<TIF_FREEZE)
#define _TIF_NOTSC		(1<<TIF_NOTSC)

/* work to do on interrupt/exception return */
#define _TIF_WORK_MASK \
  (0x0000FFFF & ~(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
		  _TIF_SECCOMP | _TIF_SYSCALL_EMU))
/* work to do on any return to u-space */
#define _TIF_ALLWORK_MASK	(0x0000FFFF & ~_TIF_SECCOMP)

/* flags to check in __switch_to() */
#define _TIF_WORK_CTXSW_NEXT (_TIF_IO_BITMAP | _TIF_NOTSC | _TIF_DEBUG)
#define _TIF_WORK_CTXSW_PREV (_TIF_IO_BITMAP | _TIF_NOTSC)

/*
 * Thread-synchronous status.
 *
 * This is different from the flags in that nobody else
 * ever touches our thread-synchronous status, so we don't
 * have to worry about atomic accesses.
 */
#define TS_USEDFPU		0x0001	/* FPU was used by this task this quantum (SMP) */
#define TS_POLLING		0x0002	/* True if in idle loop and not sleeping */

#define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)

#endif /* __KERNEL__ */

#endif /* _ASM_THREAD_INFO_H */
Commit	Line	Data
1da177e4 LT	1	/* thread_info.h: i386 low-level thread information
	2	*
	3	* Copyright (C) 2002 David Howells (dhowells@redhat.com)
	4	* - Incorporating suggestions made by Linus Torvalds and Dave Miller
	5	*/
	6
	7	#ifndef _ASM_THREAD_INFO_H
	8	#define _ASM_THREAD_INFO_H
	9
	10	#ifdef __KERNEL__
	11
1da177e4 LT	12	#include <linux/compiler.h>
	13	#include <asm/page.h>
	14
	15	#ifndef __ASSEMBLY__
	16	#include <asm/processor.h>
	17	#endif
	18
	19	/*
	20	* low level task data that entry.S needs immediate access to
	21	* - this struct should fit entirely inside of one cache line
	22	* - this struct shares the supervisor stack pages
	23	* - if the contents of this structure are changed, the assembly constants must also be changed
	24	*/
	25	#ifndef __ASSEMBLY__
	26
	27	struct thread_info {
	28	struct task_struct task; / main task structure */
	29	struct exec_domain exec_domain; / execution domain */
	30	unsigned long flags; /* low level flags */
	31	unsigned long status; /* thread-synchronous flags */
	32	__u32 cpu; /* current CPU */
dcd497f9	33	int preempt_count; /* 0 => preemptable, <0 => BUG */
1da177e4 LT	34
	35
	36	mm_segment_t addr_limit; /* thread address space:
	37	0-0xBFFFFFFF for user-thead
	38	0-0xFFFFFFFF for kernel-thread
	39	*/
e6e5494c	40	void *sysenter_return;
1da177e4 LT	41	struct restart_block restart_block;
	42
	43	unsigned long previous_esp; /* ESP of the previous stack in case
	44	of nested (IRQ) stacks
	45	*/
	46	__u8 supervisor_stack[0];
	47	};
	48
	49	#else /* !__ASSEMBLY__ */
	50
86feeaa8	51	#include <asm/asm-offsets.h>
1da177e4 LT	52
	53	#endif
	54
	55	#define PREEMPT_ACTIVE 0x10000000
	56	#ifdef CONFIG_4KSTACKS
	57	#define THREAD_SIZE (4096)
	58	#else
	59	#define THREAD_SIZE (8192)
	60	#endif
	61
	62	#define STACK_WARN (THREAD_SIZE/8)
	63	/*
	64	* macros/functions for gaining access to the thread information structure
	65	*
	66	* preempt_count needs to be 1 initially, until the scheduler is functional.
	67	*/
	68	#ifndef __ASSEMBLY__
	69
	70	#define INIT_THREAD_INFO(tsk) \
	71	{ \
	72	.task = &tsk, \
	73	.exec_domain = &default_exec_domain, \
	74	.flags = 0, \
	75	.cpu = 0, \
	76	.preempt_count = 1, \
	77	.addr_limit = KERNEL_DS, \
	78	.restart_block = { \
	79	.fn = do_no_restart_syscall, \
	80	}, \
	81	}
	82
	83	#define init_thread_info (init_thread_union.thread_info)
	84	#define init_stack (init_thread_union.stack)
	85
	86
c723e084 CE	87	/* how to get the current stack pointer from C */
	88	register unsigned long current_stack_pointer asm("esp") __attribute_used__;
	89
1da177e4 LT	90	/* how to get the thread information struct from C */
	91	static inline struct thread_info *current_thread_info(void)
	92	{
c723e084	93	return (struct thread_info *)(current_stack_pointer & ~(THREAD_SIZE - 1));
1da177e4 LT	94	}
1da177e4 LT	95
1da177e4 LT	96	/* thread information allocation */
1da177e4 LT	97	#ifdef CONFIG_DEBUG_STACK_USAGE
b5637e65 CL	98	#define alloc_thread_info(tsk) ((struct thread_info *) \
b5637e65 CL	99	__get_free_pages(GFP_KERNEL\| __GFP_ZERO, get_order(THREAD_SIZE)))
1da177e4	100	#else
b5637e65 CL	101	#define alloc_thread_info(tsk) ((struct thread_info *) \
b5637e65 CL	102	__get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE)))
1da177e4 LT	103	#endif
1da177e4 LT	104
b5637e65	105	#define free_thread_info(info) free_pages((unsigned long)(info), get_order(THREAD_SIZE))
1da177e4 LT	106
	107	#else /* !__ASSEMBLY__ */
	108
	109	/* how to get the thread information struct from ASM */
	110	#define GET_THREAD_INFO(reg) \
	111	movl $-THREAD_SIZE, reg; \
	112	andl %esp, reg
	113
	114	/* use this one if reg already contains %esp */
	115	#define GET_THREAD_INFO_WITH_ESP(reg) \
	116	andl $-THREAD_SIZE, reg
	117
	118	#endif
	119
	120	/*
	121	* thread information flags
	122	* - these are process state flags that various assembly files may need to access
	123	* - pending work-to-be-done flags are in LSW
	124	* - other flags in MSW
	125	*/
	126	#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
a583f1b5 SE	127	#define TIF_SIGPENDING 1 /* signal pending */
	128	#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
	129	#define TIF_SINGLESTEP 3 /* restore singlestep on return to user mode */
	130	#define TIF_IRET 4 /* return with iret */
	131	#define TIF_SYSCALL_EMU 5 /* syscall emulation active */
	132	#define TIF_SYSCALL_AUDIT 6 /* syscall auditing active */
	133	#define TIF_SECCOMP 7 /* secure computing */
	134	#define TIF_RESTORE_SIGMASK 8 /* restore signal mask in do_signal() */
495ab9c0	135	#define TIF_MEMDIE 16
b3cf2576 SE	136	#define TIF_DEBUG 17 /* uses debug registers */
b3cf2576 SE	137	#define TIF_IO_BITMAP 18 /* uses I/O bitmap */
8a102eed	138	#define TIF_FREEZE 19 /* is freezing for suspend */
cf99abac	139	#define TIF_NOTSC 20 /* TSC is not accessible in userland */
1da177e4 LT	140
1da177e4 LT	141	#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
1da177e4 LT	142	#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
	143	#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
	144	#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
	145	#define _TIF_IRET (1<<TIF_IRET)
ed75e8d5	146	#define _TIF_SYSCALL_EMU (1<<TIF_SYSCALL_EMU)
1da177e4 LT	147	#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
1da177e4 LT	148	#define _TIF_SECCOMP (1<<TIF_SECCOMP)
283828f3	149	#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
b3cf2576 SE	150	#define _TIF_DEBUG (1<<TIF_DEBUG)
b3cf2576 SE	151	#define _TIF_IO_BITMAP (1<<TIF_IO_BITMAP)
8a102eed	152	#define _TIF_FREEZE (1<<TIF_FREEZE)
cf99abac	153	#define _TIF_NOTSC (1<<TIF_NOTSC)
1da177e4 LT	154
	155	/* work to do on interrupt/exception return */
	156	#define _TIF_WORK_MASK \
cfe91f9c CE	157	(0x0000FFFF & ~(_TIF_SYSCALL_TRACE \| _TIF_SYSCALL_AUDIT \| \
cfe91f9c CE	158	_TIF_SECCOMP \| _TIF_SYSCALL_EMU))
1da177e4 LT	159	/* work to do on any return to u-space */
	160	#define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
	161
b3cf2576	162	/* flags to check in __switch_to() */
cf99abac AA	163	#define _TIF_WORK_CTXSW_NEXT (_TIF_IO_BITMAP \| _TIF_NOTSC \| _TIF_DEBUG)
cf99abac AA	164	#define _TIF_WORK_CTXSW_PREV (_TIF_IO_BITMAP \| _TIF_NOTSC)
b3cf2576	165
1da177e4 LT	166	/*
	167	* Thread-synchronous status.
	168	*
	169	* This is different from the flags in that nobody else
	170	* ever touches our thread-synchronous status, so we don't
	171	* have to worry about atomic accesses.
	172	*/
	173	#define TS_USEDFPU 0x0001 /* FPU was used by this task this quantum (SMP) */
495ab9c0 AK	174	#define TS_POLLING 0x0002 /* True if in idle loop and not sleeping */
495ab9c0 AK	175
c9f4f06d	176	#define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
1da177e4 LT	177
	178	#endif /* __KERNEL__ */
	179
	180	#endif /* _ASM_THREAD_INFO_H */