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 #ifdef CONFIG_KASAN 15 #define KASAN_STACK_ORDER 1 16 #else 17 #define KASAN_STACK_ORDER 0 18 #endif 19 20 /* thread information allocation */ 21 #ifdef CONFIG_64BIT 22 #define THREAD_SIZE_ORDER (2 + KASAN_STACK_ORDER) 23 #else 24 #define THREAD_SIZE_ORDER (1 + KASAN_STACK_ORDER) 25 #endif 26 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) 27 28 /* 29 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by 30 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry 31 * assembly. 32 */ 33 #ifdef CONFIG_VMAP_STACK 34 #define THREAD_ALIGN (2 * THREAD_SIZE) 35 #else 36 #define THREAD_ALIGN THREAD_SIZE 37 #endif 38 39 #define THREAD_SHIFT (PAGE_SHIFT + THREAD_SIZE_ORDER) 40 #define OVERFLOW_STACK_SIZE SZ_4K 41 #define SHADOW_OVERFLOW_STACK_SIZE (1024) 42 43 #ifndef __ASSEMBLY__ 44 45 extern long shadow_stack[SHADOW_OVERFLOW_STACK_SIZE / sizeof(long)]; 46 47 #include <asm/processor.h> 48 #include <asm/csr.h> 49 50 /* 51 * low level task data that entry.S needs immediate access to 52 * - this struct should fit entirely inside of one cache line 53 * - if the members of this struct changes, the assembly constants 54 * in asm-offsets.c must be updated accordingly 55 * - thread_info is included in task_struct at an offset of 0. This means that 56 * tp points to both thread_info and task_struct. 57 */ 58 struct thread_info { 59 unsigned long flags; /* low level flags */ 60 int preempt_count; /* 0=>preemptible, <0=>BUG */ 61 /* 62 * These stack pointers are overwritten on every system call or 63 * exception. SP is also saved to the stack it can be recovered when 64 * overwritten. 65 */ 66 long kernel_sp; /* Kernel stack pointer */ 67 long user_sp; /* User stack pointer */ 68 int cpu; 69 }; 70 71 /* 72 * macros/functions for gaining access to the thread information structure 73 * 74 * preempt_count needs to be 1 initially, until the scheduler is functional. 75 */ 76 #define INIT_THREAD_INFO(tsk) \ 77 { \ 78 .flags = 0, \ 79 .preempt_count = INIT_PREEMPT_COUNT, \ 80 } 81 82 #endif /* !__ASSEMBLY__ */ 83 84 /* 85 * thread information flags 86 * - these are process state flags that various assembly files may need to 87 * access 88 * - pending work-to-be-done flags are in lowest half-word 89 * - other flags in upper half-word(s) 90 */ 91 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 92 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 93 #define TIF_SIGPENDING 2 /* signal pending */ 94 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 95 #define TIF_RESTORE_SIGMASK 4 /* restore signal mask in do_signal() */ 96 #define TIF_MEMDIE 5 /* is terminating due to OOM killer */ 97 #define TIF_SYSCALL_TRACEPOINT 6 /* syscall tracepoint instrumentation */ 98 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing */ 99 #define TIF_SECCOMP 8 /* syscall secure computing */ 100 #define TIF_NOTIFY_SIGNAL 9 /* signal notifications exist */ 101 #define TIF_UPROBE 10 /* uprobe breakpoint or singlestep */ 102 #define TIF_32BIT 11 /* compat-mode 32bit process */ 103 104 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 105 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 106 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 107 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 108 #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) 109 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) 110 #define _TIF_SECCOMP (1 << TIF_SECCOMP) 111 #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) 112 #define _TIF_UPROBE (1 << TIF_UPROBE) 113 114 #define _TIF_WORK_MASK \ 115 (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED | \ 116 _TIF_NOTIFY_SIGNAL | _TIF_UPROBE) 117 118 #define _TIF_SYSCALL_WORK \ 119 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT | \ 120 _TIF_SECCOMP) 121 122 #endif /* _ASM_RISCV_THREAD_INFO_H */ 123