thread_info.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef _ALPHA_THREAD_INFO_H
  3#define _ALPHA_THREAD_INFO_H
  4
  5#ifdef __KERNEL__
  6
  7#ifndef __ASSEMBLER__
  8#include <asm/processor.h>
  9#include <asm/types.h>
 10#include <asm/hwrpb.h>
 11#include <asm/sysinfo.h>
 12#endif
 13
 14#ifndef __ASSEMBLER__
 15struct thread_info {
 16	struct pcb_struct	pcb;		/* palcode state */
 17
 18	struct task_struct	*task;		/* main task structure */
 19	unsigned int		flags;		/* low level flags */
 20	unsigned int		ieee_state;	/* see fpu.h */
 21
 22	unsigned		cpu;		/* current CPU */
 23	int			preempt_count; /* 0 => preemptable, <0 => BUG */
 24	unsigned int		status;		/* thread-synchronous flags */
 25
 26	int bpt_nsaved;
 27	unsigned long bpt_addr[2];		/* breakpoint handling  */
 28	unsigned int bpt_insn[2];
 29	unsigned long fp[32];
 30};
 31
 32/*
 33 * Macros/functions for gaining access to the thread information structure.
 34 */
 35#define INIT_THREAD_INFO(tsk)			\
 36{						\
 37	.task		= &tsk,			\
 38	.preempt_count	= INIT_PREEMPT_COUNT,	\
 39}
 40
 41/* How to get the thread information struct from C.  */
 42register struct thread_info *__current_thread_info __asm__("$8");
 43#define current_thread_info()  __current_thread_info
 44
 45register unsigned long *current_stack_pointer __asm__ ("$30");
 46
 47#endif /* __ASSEMBLER__ */
 48
 49/* Thread information allocation.  */
 50#define THREAD_SIZE_ORDER 1
 51#define THREAD_SIZE (2*PAGE_SIZE)
 52
 53/*
 54 * Thread information flags:
 55 * - these are process state flags and used from assembly
 56 * - pending work-to-be-done flags come first and must be assigned to be
 57 *   within bits 0 to 7 to fit in and immediate operand.
 58 *
 59 * TIF_SYSCALL_TRACE is known to be 0 via blbs.
 60 */
 61#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
 62#define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
 63#define TIF_SIGPENDING		2	/* signal pending */
 64#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
 65#define TIF_SYSCALL_AUDIT	4	/* syscall audit active */
 66#define TIF_NOTIFY_SIGNAL	5	/* signal notifications exist */
 67#define TIF_DIE_IF_KERNEL	9	/* dik recursion lock */
 68#define TIF_MEMDIE		13	/* is terminating due to OOM killer */
 69#define TIF_POLLING_NRFLAG	14	/* idle is polling for TIF_NEED_RESCHED */
 70
 71#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 72#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 73#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 74#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
 75#define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
 76#define _TIF_NOTIFY_SIGNAL	(1<<TIF_NOTIFY_SIGNAL)
 77#define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 78
 79/* Work to do on interrupt/exception return.  */
 80#define _TIF_WORK_MASK		(_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
 81				 _TIF_NOTIFY_RESUME | _TIF_NOTIFY_SIGNAL)
 82
 83#define TS_UAC_NOPRINT		0x0001	/* ! Preserve the following three */
 84#define TS_UAC_NOFIX		0x0002	/* ! flags as they match          */
 85#define TS_UAC_SIGBUS		0x0004	/* ! userspace part of 'osf_sysinfo' */
 86
 87#define TS_SAVED_FP		0x0008
 88#define TS_RESTORE_FP		0x0010
 89
 90#define SET_UNALIGN_CTL(task,value)	({				\
 91	__u32 status = task_thread_info(task)->status & ~UAC_BITMASK;	\
 92	if (value & PR_UNALIGN_NOPRINT)					\
 93		status |= TS_UAC_NOPRINT;				\
 94	if (value & PR_UNALIGN_SIGBUS)					\
 95		status |= TS_UAC_SIGBUS;				\
 96	if (value & 4)	/* alpha-specific */				\
 97		status |= TS_UAC_NOFIX;					\
 98	task_thread_info(task)->status = status;			\
 99	0; })
100
101#define GET_UNALIGN_CTL(task,value)	({				\
102	__u32 status = task_thread_info(task)->status & ~UAC_BITMASK;	\
103	__u32 res = 0;							\
104	if (status & TS_UAC_NOPRINT)					\
105		res |= PR_UNALIGN_NOPRINT;				\
106	if (status & TS_UAC_SIGBUS)					\
107		res |= PR_UNALIGN_SIGBUS;				\
108	if (status & TS_UAC_NOFIX)					\
109		res |= 4;						\
110	put_user(res, (int __user *)(value));				\
111	})
112
113#ifndef __ASSEMBLER__
114extern void __save_fpu(void);
115
116static inline void save_fpu(void)
117{
118	if (!(current_thread_info()->status & TS_SAVED_FP)) {
119		current_thread_info()->status |= TS_SAVED_FP;
120		__save_fpu();
121	}
122}
123#endif
124
125#endif /* __KERNEL__ */
126#endif /* _ALPHA_THREAD_INFO_H */