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 #include <linux/sizes.h>
14
15 /* thread information allocation */
16 #ifdef CONFIG_KASAN
17 #define KASAN_STACK_ORDER 1
18 #else
19 #define KASAN_STACK_ORDER 0
20 #endif
21 #define THREAD_SIZE_ORDER (CONFIG_THREAD_SIZE_ORDER + KASAN_STACK_ORDER)
22 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
23
24 /*
25 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
26 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
27 * assembly.
28 */
29 #ifdef CONFIG_VMAP_STACK
30 #define THREAD_ALIGN (2 * THREAD_SIZE)
31 #else
32 #define THREAD_ALIGN THREAD_SIZE
33 #endif
34
35 #define THREAD_SHIFT (PAGE_SHIFT + THREAD_SIZE_ORDER)
36 #define OVERFLOW_STACK_SIZE SZ_4K
37
38 #define IRQ_STACK_SIZE THREAD_SIZE
39
40 #ifndef __ASSEMBLY__
41
42 #include <asm/processor.h>
43 #include <asm/csr.h>
44
45 /*
46 * low level task data that entry.S needs immediate access to
47 * - this struct should fit entirely inside of one cache line
48 * - if the members of this struct changes, the assembly constants
49 * in asm-offsets.c must be updated accordingly
50 * - thread_info is included in task_struct at an offset of 0. This means that
51 * tp points to both thread_info and task_struct.
52 */
53 struct thread_info {
54 unsigned long flags; /* low level flags */
55 int preempt_count; /* 0=>preemptible, <0=>BUG */
56 /*
57 * These stack pointers are overwritten on every system call or
58 * exception. SP is also saved to the stack it can be recovered when
59 * overwritten.
60 */
61 long kernel_sp; /* Kernel stack pointer */
62 long user_sp; /* User stack pointer */
63 int cpu;
64 unsigned long syscall_work; /* SYSCALL_WORK_ flags */
65 #ifdef CONFIG_SHADOW_CALL_STACK
66 void *scs_base;
67 void *scs_sp;
68 #endif
69 };
70
71 #ifdef CONFIG_SHADOW_CALL_STACK
72 #define INIT_SCS \
73 .scs_base = init_shadow_call_stack, \
74 .scs_sp = init_shadow_call_stack,
75 #else
76 #define INIT_SCS
77 #endif
78
79 /*
80 * macros/functions for gaining access to the thread information structure
81 *
82 * preempt_count needs to be 1 initially, until the scheduler is functional.
83 */
84 #define INIT_THREAD_INFO(tsk) \
85 { \
86 .flags = 0, \
87 .preempt_count = INIT_PREEMPT_COUNT, \
88 INIT_SCS \
89 }
90
91 void arch_release_task_struct(struct task_struct *tsk);
92 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
93
94 #endif /* !__ASSEMBLY__ */
95
96 /*
97 * thread information flags
98 * - these are process state flags that various assembly files may need to
99 * access
100 * - pending work-to-be-done flags are in lowest half-word
101 * - other flags in upper half-word(s)
102 */
103 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */
104 #define TIF_SIGPENDING 2 /* signal pending */
105 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */
106 #define TIF_RESTORE_SIGMASK 4 /* restore signal mask in do_signal() */
107 #define TIF_MEMDIE 5 /* is terminating due to OOM killer */
108 #define TIF_NOTIFY_SIGNAL 9 /* signal notifications exist */
109 #define TIF_UPROBE 10 /* uprobe breakpoint or singlestep */
110 #define TIF_32BIT 11 /* compat-mode 32bit process */
111 #define TIF_RISCV_V_DEFER_RESTORE 12 /* restore Vector before returing to user */
112
113 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
114 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
115 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
116 #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL)
117 #define _TIF_UPROBE (1 << TIF_UPROBE)
118 #define _TIF_RISCV_V_DEFER_RESTORE (1 << TIF_RISCV_V_DEFER_RESTORE)
119
120 #define _TIF_WORK_MASK \
121 (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED | \
122 _TIF_NOTIFY_SIGNAL | _TIF_UPROBE)
123
124 #endif /* _ASM_RISCV_THREAD_INFO_H */
125
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