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 #define SHADOW_OVERFLOW_STACK_SIZE (1024) 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 }; 61 62 /* 63 * macros/functions for gaining access to the thread information structure 64 * 65 * preempt_count needs to be 1 initially, until the scheduler is functional. 66 */ 67 #define INIT_THREAD_INFO(tsk) \ 68 { \ 69 .flags = 0, \ 70 .preempt_count = INIT_PREEMPT_COUNT, \ 71 } 72 73 void arch_release_task_struct(struct task_struct *tsk); 74 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 75 76 #endif /* !__ASSEMBLY__ */ 77 78 /* 79 * thread information flags 80 * - these are process state flags that various assembly files may need to 81 * access 82 * - pending work-to-be-done flags are in lowest half-word 83 * - other flags in upper half-word(s) 84 */ 85 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 86 #define TIF_SIGPENDING 2 /* signal pending */ 87 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 88 #define TIF_RESTORE_SIGMASK 4 /* restore signal mask in do_signal() */ 89 #define TIF_MEMDIE 5 /* is terminating due to OOM killer */ 90 #define TIF_NOTIFY_SIGNAL 9 /* signal notifications exist */ 91 #define TIF_UPROBE 10 /* uprobe breakpoint or singlestep */ 92 #define TIF_32BIT 11 /* compat-mode 32bit process */ 93 94 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 95 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 96 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 97 #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) 98 #define _TIF_UPROBE (1 << TIF_UPROBE) 99 100 #define _TIF_WORK_MASK \ 101 (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED | \ 102 _TIF_NOTIFY_SIGNAL | _TIF_UPROBE) 103 104 #endif /* _ASM_RISCV_THREAD_INFO_H */ 105