LXR linux/arch/riscv/include/asm/thread

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
   4 * Copyright (C) 2012 Regents of the University of California
   5 * Copyright (C) 2017 SiFive
   6 */
   7
   8#ifndef _ASM_RISCV_THREAD_INFO_H
   9#define _ASM_RISCV_THREAD_INFO_H
  10
  11#include <asm/page.h>
  12#include <linux/const.h>
  13
  14/* thread information allocation */
  15#ifdef CONFIG_64BIT
  16#define THREAD_SIZE_ORDER       (2)
  17#else
  18#define THREAD_SIZE_ORDER       (1)
  19#endif
  20#define THREAD_SIZE             (PAGE_SIZE << THREAD_SIZE_ORDER)
  21
  22/*
  23 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
  24 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
  25 * assembly.
  26 */
  27#ifdef CONFIG_VMAP_STACK
  28#define THREAD_ALIGN            (2 * THREAD_SIZE)
  29#else
  30#define THREAD_ALIGN            THREAD_SIZE
  31#endif
  32
  33#define THREAD_SHIFT            (PAGE_SHIFT + THREAD_SIZE_ORDER)
  34#define OVERFLOW_STACK_SIZE     SZ_4K
  35#define SHADOW_OVERFLOW_STACK_SIZE (1024)
  36
  37#ifndef __ASSEMBLY__
  38
  39#include <asm/processor.h>
  40#include <asm/csr.h>
  41
  42/*
  43 * low level task data that entry.S needs immediate access to
  44 * - this struct should fit entirely inside of one cache line
  45 * - if the members of this struct changes, the assembly constants
  46 *   in asm-offsets.c must be updated accordingly
  47 * - thread_info is included in task_struct at an offset of 0.  This means that
  48 *   tp points to both thread_info and task_struct.
  49 */
  50struct thread_info {
  51        unsigned long           flags;          /* low level flags */
  52        int                     preempt_count;  /* 0=>preemptible, <0=>BUG */
  53        /*
  54         * These stack pointers are overwritten on every system call or
  55         * exception.  SP is also saved to the stack it can be recovered when
  56         * overwritten.
  57         */
  58        long                    kernel_sp;      /* Kernel stack pointer */
  59        long                    user_sp;        /* User stack pointer */
  60        int                     cpu;
  61};
  62
  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#define INIT_THREAD_INFO(tsk)                   \
  69{                                               \
  70        .flags          = 0,                    \
  71        .preempt_count  = INIT_PREEMPT_COUNT,   \
  72}
  73
  74#endif /* !__ASSEMBLY__ */
  75
  76/*
  77 * thread information flags
  78 * - these are process state flags that various assembly files may need to
  79 *   access
  80 * - pending work-to-be-done flags are in lowest half-word
  81 * - other flags in upper half-word(s)
  82 */
  83#define TIF_SYSCALL_TRACE       0       /* syscall trace active */
  84#define TIF_NOTIFY_RESUME       1       /* callback before returning to user */
  85#define TIF_SIGPENDING          2       /* signal pending */
  86#define TIF_NEED_RESCHED        3       /* rescheduling necessary */
  87#define TIF_RESTORE_SIGMASK     4       /* restore signal mask in do_signal() */
  88#define TIF_MEMDIE              5       /* is terminating due to OOM killer */
  89#define TIF_SYSCALL_TRACEPOINT  6       /* syscall tracepoint instrumentation */
  90#define TIF_SYSCALL_AUDIT       7       /* syscall auditing */
  91#define TIF_SECCOMP             8       /* syscall secure computing */
  92#define TIF_NOTIFY_SIGNAL       9       /* signal notifications exist */
  93#define TIF_UPROBE              10      /* uprobe breakpoint or singlestep */
  94
  95#define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
  96#define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
  97#define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
  98#define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
  99#define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT)
 100#define _TIF_SYSCALL_AUDIT      (1 << TIF_SYSCALL_AUDIT)
 101#define _TIF_SECCOMP            (1 << TIF_SECCOMP)
 102#define _TIF_NOTIFY_SIGNAL      (1 << TIF_NOTIFY_SIGNAL)
 103#define _TIF_UPROBE             (1 << TIF_UPROBE)
 104
 105#define _TIF_WORK_MASK \
 106        (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED | \
 107         _TIF_NOTIFY_SIGNAL | _TIF_UPROBE)
 108
 109#define _TIF_SYSCALL_WORK \
 110        (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT | \
 111         _TIF_SECCOMP)
 112
 113#endif /* _ASM_RISCV_THREAD_INFO_H */
 114