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 */ 47 struct 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 85 void arch_release_task_struct(struct task_struct *tsk); 86 int 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 */ 119