Linux kernel mirror (for testing)
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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#define THREAD_SIZE_ORDER CONFIG_THREAD_SIZE_ORDER
16#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
17
18/*
19 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
20 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
21 * assembly.
22 */
23#ifdef CONFIG_VMAP_STACK
24#define THREAD_ALIGN (2 * THREAD_SIZE)
25#else
26#define THREAD_ALIGN THREAD_SIZE
27#endif
28
29#define THREAD_SHIFT (PAGE_SHIFT + THREAD_SIZE_ORDER)
30#define OVERFLOW_STACK_SIZE SZ_4K
31
32#define IRQ_STACK_SIZE THREAD_SIZE
33
34#ifndef __ASSEMBLY__
35
36#include <asm/processor.h>
37#include <asm/csr.h>
38
39/*
40 * low level task data that entry.S needs immediate access to
41 * - this struct should fit entirely inside of one cache line
42 * - if the members of this struct changes, the assembly constants
43 * in asm-offsets.c must be updated accordingly
44 * - thread_info is included in task_struct at an offset of 0. This means that
45 * tp points to both thread_info and task_struct.
46 */
47struct thread_info {
48 unsigned long flags; /* low level flags */
49 int preempt_count; /* 0=>preemptible, <0=>BUG */
50 /*
51 * These stack pointers are overwritten on every system call or
52 * exception. SP is also saved to the stack it can be recovered when
53 * overwritten.
54 */
55 long kernel_sp; /* Kernel stack pointer */
56 long user_sp; /* User stack pointer */
57 int cpu;
58 unsigned long syscall_work; /* SYSCALL_WORK_ flags */
59#ifdef CONFIG_SHADOW_CALL_STACK
60 void *scs_base;
61 void *scs_sp;
62#endif
63};
64
65#ifdef CONFIG_SHADOW_CALL_STACK
66#define INIT_SCS \
67 .scs_base = init_shadow_call_stack, \
68 .scs_sp = init_shadow_call_stack,
69#else
70#define INIT_SCS
71#endif
72
73/*
74 * macros/functions for gaining access to the thread information structure
75 *
76 * preempt_count needs to be 1 initially, until the scheduler is functional.
77 */
78#define INIT_THREAD_INFO(tsk) \
79{ \
80 .flags = 0, \
81 .preempt_count = INIT_PREEMPT_COUNT, \
82 INIT_SCS \
83}
84
85void arch_release_task_struct(struct task_struct *tsk);
86int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
87
88#endif /* !__ASSEMBLY__ */
89
90/*
91 * thread information flags
92 * - these are process state flags that various assembly files may need to
93 * access
94 * - pending work-to-be-done flags are in lowest half-word
95 * - other flags in upper half-word(s)
96 */
97#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */
98#define TIF_SIGPENDING 2 /* signal pending */
99#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
100#define TIF_RESTORE_SIGMASK 4 /* restore signal mask in do_signal() */
101#define TIF_MEMDIE 5 /* is terminating due to OOM killer */
102#define TIF_NOTIFY_SIGNAL 9 /* signal notifications exist */
103#define TIF_UPROBE 10 /* uprobe breakpoint or singlestep */
104#define TIF_32BIT 11 /* compat-mode 32bit process */
105#define TIF_RISCV_V_DEFER_RESTORE 12 /* restore Vector before returing to user */
106
107#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
108#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
109#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
110#define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL)
111#define _TIF_UPROBE (1 << TIF_UPROBE)
112#define _TIF_RISCV_V_DEFER_RESTORE (1 << TIF_RISCV_V_DEFER_RESTORE)
113
114#define _TIF_WORK_MASK \
115 (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED | \
116 _TIF_NOTIFY_SIGNAL | _TIF_UPROBE)
117
118#endif /* _ASM_RISCV_THREAD_INFO_H */