thread_info.h

  1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * Thread support for the Hexagon architecture
  4 *
  5 * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
  6 */
  7
  8#ifndef _ASM_THREAD_INFO_H
  9#define _ASM_THREAD_INFO_H
 10
 11#ifdef __KERNEL__
 12
 13#ifndef __ASSEMBLY__
 14#include <asm/processor.h>
 15#include <asm/registers.h>
 16#include <asm/page.h>
 17#endif
 18
 19#define THREAD_SHIFT		12
 20#define THREAD_SIZE		(1<<THREAD_SHIFT)
 21#define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
 22
 23#ifndef __ASSEMBLY__
 24
 25/*
 26 * This is union'd with the "bottom" of the kernel stack.
 27 * It keeps track of thread info which is handy for routines
 28 * to access quickly.
 29 */
 30
 31struct thread_info {
 32	struct task_struct	*task;		/* main task structure */
 33	unsigned long		flags;          /* low level flags */
 34	__u32                   cpu;            /* current cpu */
 35	int                     preempt_count;  /* 0=>preemptible,<0=>BUG */
 36	/*
 37	 * used for syscalls somehow;
 38	 * seems to have a function pointer and four arguments
 39	 */
 40	/* Points to the current pt_regs frame  */
 41	struct pt_regs		*regs;
 42	/*
 43	 * saved kernel sp at switch_to time;
 44	 * not sure if this is used (it's not in the VM model it seems;
 45	 * see thread_struct)
 46	 */
 47	unsigned long		sp;
 48};
 49
 50#else /* !__ASSEMBLY__ */
 51
 52#include <asm/asm-offsets.h>
 53
 54#endif  /* __ASSEMBLY__  */
 55
 56#ifndef __ASSEMBLY__
 57
 58#define INIT_THREAD_INFO(tsk)                   \
 59{                                               \
 60	.task           = &tsk,                 \
 61	.flags          = 0,                    \
 62	.cpu            = 0,                    \
 63	.preempt_count  = 1,                    \
 64	.sp = 0,				\
 65	.regs = NULL,			\
 66}
 67
 68/* Tacky preprocessor trickery */
 69#define	qqstr(s) qstr(s)
 70#define qstr(s) #s
 71#define QUOTED_THREADINFO_REG qqstr(THREADINFO_REG)
 72
 73register struct thread_info *__current_thread_info asm(QUOTED_THREADINFO_REG);
 74#define current_thread_info()  __current_thread_info
 75
 76#endif /* __ASSEMBLY__ */
 77
 78/*
 79 * thread information flags
 80 * - these are process state flags that various assembly files
 81 *   may need to access
 82 * - pending work-to-be-done flags are in LSW
 83 * - other flags in MSW
 84 */
 85
 86#define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 87#define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 88#define TIF_SIGPENDING          2       /* signal pending */
 89#define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 90#define TIF_SINGLESTEP          4       /* restore ss @ return to usr mode */
 91#define TIF_RESTORE_SIGMASK     6       /* restore sig mask in do_signal() */
 92#define TIF_NOTIFY_SIGNAL	7       /* signal notifications exist */
 93/* true if poll_idle() is polling TIF_NEED_RESCHED */
 94#define TIF_MEMDIE              17      /* OOM killer killed process */
 95
 96#define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
 97#define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
 98#define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 99#define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
100#define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
101#define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
102
103/* work to do on interrupt/exception return - All but TIF_SYSCALL_TRACE */
104#define _TIF_WORK_MASK          (0x0000FFFF & ~_TIF_SYSCALL_TRACE)
105
106/* work to do on any return to u-space */
107#define _TIF_ALLWORK_MASK       0x0000FFFF
108
109#endif /* __KERNEL__ */
110
111#endif