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