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 #ifdef CONFIG_64BIT 65 /* 66 * Used in handle_exception() to save a0, a1 and a2 before knowing if we 67 * can access the kernel stack. 68 */ 69 unsigned long a0, a1, a2; 70 #endif 71 }; 72 73 #ifdef CONFIG_SHADOW_CALL_STACK 74 #define INIT_SCS \ 75 .scs_base = init_shadow_call_stack, \ 76 .scs_sp = init_shadow_call_stack, 77 #else 78 #define INIT_SCS 79 #endif 80 81 /* 82 * macros/functions for gaining access to the thread information structure 83 * 84 * preempt_count needs to be 1 initially, until the scheduler is functional. 85 */ 86 #define INIT_THREAD_INFO(tsk) \ 87 { \ 88 .flags = 0, \ 89 .preempt_count = INIT_PREEMPT_COUNT, \ 90 INIT_SCS \ 91 } 92 93 void arch_release_task_struct(struct task_struct *tsk); 94 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 95 96 #endif /* !__ASSEMBLY__ */ 97 98 /* 99 * thread information flags 100 * - these are process state flags that various assembly files may need to 101 * access 102 * - pending work-to-be-done flags are in lowest half-word 103 * - other flags in upper half-word(s) 104 */ 105 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 106 #define TIF_SIGPENDING 2 /* signal pending */ 107 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 108 #define TIF_RESTORE_SIGMASK 4 /* restore signal mask in do_signal() */ 109 #define TIF_MEMDIE 5 /* is terminating due to OOM killer */ 110 #define TIF_NOTIFY_SIGNAL 9 /* signal notifications exist */ 111 #define TIF_UPROBE 10 /* uprobe breakpoint or singlestep */ 112 #define TIF_32BIT 11 /* compat-mode 32bit process */ 113 #define TIF_RISCV_V_DEFER_RESTORE 12 /* restore Vector before returing to user */ 114 115 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 116 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 117 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 118 #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) 119 #define _TIF_UPROBE (1 << TIF_UPROBE) 120 #define _TIF_RISCV_V_DEFER_RESTORE (1 << TIF_RISCV_V_DEFER_RESTORE) 121 122 #endif /* _ASM_RISCV_THREAD_INFO_H */ 123