1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* thread_info.h: common low-level thread information accessors 3 * 4 * Copyright (C) 2002 David Howells (dhowells@redhat.com) 5 * - Incorporating suggestions made by Linus Torvalds 6 */ 7 8 #ifndef _LINUX_THREAD_INFO_H 9 #define _LINUX_THREAD_INFO_H 10 11 #include <linux/types.h> 12 #include <linux/limits.h> 13 #include <linux/bug.h> 14 #include <linux/restart_block.h> 15 #include <linux/errno.h> 16 17 #ifdef CONFIG_THREAD_INFO_IN_TASK 18 /* 19 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the 20 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels, 21 * including <asm/current.h> can cause a circular dependency on some platforms. 22 */ 23 #include <asm/current.h> 24 #define current_thread_info() ((struct thread_info *)current) 25 #endif 26 27 #include <linux/bitops.h> 28 29 /* 30 * For per-arch arch_within_stack_frames() implementations, defined in 31 * asm/thread_info.h. 32 */ 33 enum { 34 BAD_STACK = -1, 35 NOT_STACK = 0, 36 GOOD_FRAME, 37 GOOD_STACK, 38 }; 39 40 #ifdef CONFIG_GENERIC_ENTRY 41 enum syscall_work_bit { 42 SYSCALL_WORK_BIT_SECCOMP, 43 SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT, 44 SYSCALL_WORK_BIT_SYSCALL_TRACE, 45 SYSCALL_WORK_BIT_SYSCALL_EMU, 46 SYSCALL_WORK_BIT_SYSCALL_AUDIT, 47 SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH, 48 SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP, 49 }; 50 51 #define SYSCALL_WORK_SECCOMP BIT(SYSCALL_WORK_BIT_SECCOMP) 52 #define SYSCALL_WORK_SYSCALL_TRACEPOINT BIT(SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT) 53 #define SYSCALL_WORK_SYSCALL_TRACE BIT(SYSCALL_WORK_BIT_SYSCALL_TRACE) 54 #define SYSCALL_WORK_SYSCALL_EMU BIT(SYSCALL_WORK_BIT_SYSCALL_EMU) 55 #define SYSCALL_WORK_SYSCALL_AUDIT BIT(SYSCALL_WORK_BIT_SYSCALL_AUDIT) 56 #define SYSCALL_WORK_SYSCALL_USER_DISPATCH BIT(SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH) 57 #define SYSCALL_WORK_SYSCALL_EXIT_TRAP BIT(SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP) 58 #endif 59 60 #include <asm/thread_info.h> 61 62 #ifndef TIF_NEED_RESCHED_LAZY 63 #ifdef CONFIG_ARCH_HAS_PREEMPT_LAZY 64 #error Inconsistent PREEMPT_LAZY 65 #endif 66 #define TIF_NEED_RESCHED_LAZY TIF_NEED_RESCHED 67 #define _TIF_NEED_RESCHED_LAZY _TIF_NEED_RESCHED 68 #endif 69 70 #ifndef TIF_RSEQ 71 # define TIF_RSEQ TIF_NOTIFY_RESUME 72 # define _TIF_RSEQ _TIF_NOTIFY_RESUME 73 #endif 74 75 #ifdef __KERNEL__ 76 77 #ifndef arch_set_restart_data 78 #define arch_set_restart_data(restart) do { } while (0) 79 #endif 80 81 static inline long set_restart_fn(struct restart_block *restart, 82 long (*fn)(struct restart_block *)) 83 { 84 restart->fn = fn; 85 arch_set_restart_data(restart); 86 return -ERESTART_RESTARTBLOCK; 87 } 88 89 #ifndef THREAD_ALIGN 90 #define THREAD_ALIGN THREAD_SIZE 91 #endif 92 93 #define THREADINFO_GFP (GFP_KERNEL_ACCOUNT | __GFP_ZERO) 94 95 /* 96 * flag set/clear/test wrappers 97 * - pass TIF_xxxx constants to these functions 98 */ 99 100 static inline void set_ti_thread_flag(struct thread_info *ti, int flag) 101 { 102 set_bit(flag, (unsigned long *)&ti->flags); 103 } 104 105 static inline void clear_ti_thread_flag(struct thread_info *ti, int flag) 106 { 107 clear_bit(flag, (unsigned long *)&ti->flags); 108 } 109 110 static inline void update_ti_thread_flag(struct thread_info *ti, int flag, 111 bool value) 112 { 113 if (value) 114 set_ti_thread_flag(ti, flag); 115 else 116 clear_ti_thread_flag(ti, flag); 117 } 118 119 static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag) 120 { 121 return test_and_set_bit(flag, (unsigned long *)&ti->flags); 122 } 123 124 static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag) 125 { 126 return test_and_clear_bit(flag, (unsigned long *)&ti->flags); 127 } 128 129 static inline int test_ti_thread_flag(struct thread_info *ti, int flag) 130 { 131 return test_bit(flag, (unsigned long *)&ti->flags); 132 } 133 134 /* 135 * This may be used in noinstr code, and needs to be __always_inline to prevent 136 * inadvertent instrumentation. 137 */ 138 static __always_inline unsigned long read_ti_thread_flags(struct thread_info *ti) 139 { 140 return READ_ONCE(ti->flags); 141 } 142 143 #define set_thread_flag(flag) \ 144 set_ti_thread_flag(current_thread_info(), flag) 145 #define clear_thread_flag(flag) \ 146 clear_ti_thread_flag(current_thread_info(), flag) 147 #define update_thread_flag(flag, value) \ 148 update_ti_thread_flag(current_thread_info(), flag, value) 149 #define test_and_set_thread_flag(flag) \ 150 test_and_set_ti_thread_flag(current_thread_info(), flag) 151 #define test_and_clear_thread_flag(flag) \ 152 test_and_clear_ti_thread_flag(current_thread_info(), flag) 153 #define test_thread_flag(flag) \ 154 test_ti_thread_flag(current_thread_info(), flag) 155 #define read_thread_flags() \ 156 read_ti_thread_flags(current_thread_info()) 157 158 #define read_task_thread_flags(t) \ 159 read_ti_thread_flags(task_thread_info(t)) 160 161 #ifdef CONFIG_GENERIC_ENTRY 162 #define set_syscall_work(fl) \ 163 set_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) 164 #define test_syscall_work(fl) \ 165 test_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) 166 #define clear_syscall_work(fl) \ 167 clear_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) 168 169 #define set_task_syscall_work(t, fl) \ 170 set_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) 171 #define test_task_syscall_work(t, fl) \ 172 test_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) 173 #define clear_task_syscall_work(t, fl) \ 174 clear_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) 175 176 #else /* CONFIG_GENERIC_ENTRY */ 177 178 #define set_syscall_work(fl) \ 179 set_ti_thread_flag(current_thread_info(), TIF_##fl) 180 #define test_syscall_work(fl) \ 181 test_ti_thread_flag(current_thread_info(), TIF_##fl) 182 #define clear_syscall_work(fl) \ 183 clear_ti_thread_flag(current_thread_info(), TIF_##fl) 184 185 #define set_task_syscall_work(t, fl) \ 186 set_ti_thread_flag(task_thread_info(t), TIF_##fl) 187 #define test_task_syscall_work(t, fl) \ 188 test_ti_thread_flag(task_thread_info(t), TIF_##fl) 189 #define clear_task_syscall_work(t, fl) \ 190 clear_ti_thread_flag(task_thread_info(t), TIF_##fl) 191 #endif /* !CONFIG_GENERIC_ENTRY */ 192 193 #ifdef _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H 194 195 static __always_inline bool tif_test_bit(int bit) 196 { 197 return arch_test_bit(bit, 198 (unsigned long *)(¤t_thread_info()->flags)); 199 } 200 201 #else 202 203 static __always_inline bool tif_test_bit(int bit) 204 { 205 return test_bit(bit, 206 (unsigned long *)(¤t_thread_info()->flags)); 207 } 208 209 #endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H */ 210 211 static __always_inline bool tif_need_resched(void) 212 { 213 return tif_test_bit(TIF_NEED_RESCHED); 214 } 215 216 #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES 217 static inline int arch_within_stack_frames(const void * const stack, 218 const void * const stackend, 219 const void *obj, unsigned long len) 220 { 221 return 0; 222 } 223 #endif 224 225 #ifndef arch_setup_new_exec 226 static inline void arch_setup_new_exec(void) { } 227 #endif 228 229 void arch_task_cache_init(void); /* for CONFIG_SH */ 230 void arch_release_task_struct(struct task_struct *tsk); 231 int arch_dup_task_struct(struct task_struct *dst, 232 struct task_struct *src); 233 234 #endif /* __KERNEL__ */ 235 236 #endif /* _LINUX_THREAD_INFO_H */ 237