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 SYSCALL_WORK_BIT_SYSCALL_RSEQ_SLICE, 50 }; 51 52 #define SYSCALL_WORK_SECCOMP BIT(SYSCALL_WORK_BIT_SECCOMP) 53 #define SYSCALL_WORK_SYSCALL_TRACEPOINT BIT(SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT) 54 #define SYSCALL_WORK_SYSCALL_TRACE BIT(SYSCALL_WORK_BIT_SYSCALL_TRACE) 55 #define SYSCALL_WORK_SYSCALL_EMU BIT(SYSCALL_WORK_BIT_SYSCALL_EMU) 56 #define SYSCALL_WORK_SYSCALL_AUDIT BIT(SYSCALL_WORK_BIT_SYSCALL_AUDIT) 57 #define SYSCALL_WORK_SYSCALL_USER_DISPATCH BIT(SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH) 58 #define SYSCALL_WORK_SYSCALL_EXIT_TRAP BIT(SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP) 59 #define SYSCALL_WORK_SYSCALL_RSEQ_SLICE BIT(SYSCALL_WORK_BIT_SYSCALL_RSEQ_SLICE) 60 #endif 61 62 #include <asm/thread_info.h> 63 64 #ifndef TIF_NEED_RESCHED_LAZY 65 #ifdef CONFIG_ARCH_HAS_PREEMPT_LAZY 66 #error Inconsistent PREEMPT_LAZY 67 #endif 68 #define TIF_NEED_RESCHED_LAZY TIF_NEED_RESCHED 69 #define _TIF_NEED_RESCHED_LAZY _TIF_NEED_RESCHED 70 #endif 71 72 #ifndef TIF_RSEQ 73 # define TIF_RSEQ TIF_NOTIFY_RESUME 74 # define _TIF_RSEQ _TIF_NOTIFY_RESUME 75 #endif 76 77 #ifdef __KERNEL__ 78 79 #ifndef arch_set_restart_data 80 #define arch_set_restart_data(restart) do { } while (0) 81 #endif 82 83 static inline long set_restart_fn(struct restart_block *restart, 84 long (*fn)(struct restart_block *)) 85 { 86 restart->fn = fn; 87 arch_set_restart_data(restart); 88 return -ERESTART_RESTARTBLOCK; 89 } 90 91 #ifndef THREAD_ALIGN 92 #define THREAD_ALIGN THREAD_SIZE 93 #endif 94 95 #define THREADINFO_GFP (GFP_KERNEL_ACCOUNT | __GFP_ZERO) 96 97 /* 98 * flag set/clear/test wrappers 99 * - pass TIF_xxxx constants to these functions 100 */ 101 102 static inline void set_ti_thread_flag(struct thread_info *ti, int flag) 103 { 104 set_bit(flag, (unsigned long *)&ti->flags); 105 } 106 107 static inline void clear_ti_thread_flag(struct thread_info *ti, int flag) 108 { 109 clear_bit(flag, (unsigned long *)&ti->flags); 110 } 111 112 static inline void update_ti_thread_flag(struct thread_info *ti, int flag, 113 bool value) 114 { 115 if (value) 116 set_ti_thread_flag(ti, flag); 117 else 118 clear_ti_thread_flag(ti, flag); 119 } 120 121 static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag) 122 { 123 return test_and_set_bit(flag, (unsigned long *)&ti->flags); 124 } 125 126 static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag) 127 { 128 return test_and_clear_bit(flag, (unsigned long *)&ti->flags); 129 } 130 131 static inline int test_ti_thread_flag(struct thread_info *ti, int flag) 132 { 133 return test_bit(flag, (unsigned long *)&ti->flags); 134 } 135 136 /* 137 * This may be used in noinstr code, and needs to be __always_inline to prevent 138 * inadvertent instrumentation. 139 */ 140 static __always_inline unsigned long read_ti_thread_flags(struct thread_info *ti) 141 { 142 return READ_ONCE(ti->flags); 143 } 144 145 #define set_thread_flag(flag) \ 146 set_ti_thread_flag(current_thread_info(), flag) 147 #define clear_thread_flag(flag) \ 148 clear_ti_thread_flag(current_thread_info(), flag) 149 #define update_thread_flag(flag, value) \ 150 update_ti_thread_flag(current_thread_info(), flag, value) 151 #define test_and_set_thread_flag(flag) \ 152 test_and_set_ti_thread_flag(current_thread_info(), flag) 153 #define test_and_clear_thread_flag(flag) \ 154 test_and_clear_ti_thread_flag(current_thread_info(), flag) 155 #define test_thread_flag(flag) \ 156 test_ti_thread_flag(current_thread_info(), flag) 157 #define read_thread_flags() \ 158 read_ti_thread_flags(current_thread_info()) 159 160 #define read_task_thread_flags(t) \ 161 read_ti_thread_flags(task_thread_info(t)) 162 163 #ifdef CONFIG_GENERIC_ENTRY 164 #define set_syscall_work(fl) \ 165 set_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) 166 #define test_syscall_work(fl) \ 167 test_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) 168 #define clear_syscall_work(fl) \ 169 clear_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) 170 171 #define set_task_syscall_work(t, fl) \ 172 set_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) 173 #define test_task_syscall_work(t, fl) \ 174 test_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) 175 #define clear_task_syscall_work(t, fl) \ 176 clear_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) 177 178 #else /* CONFIG_GENERIC_ENTRY */ 179 180 #define set_syscall_work(fl) \ 181 set_ti_thread_flag(current_thread_info(), TIF_##fl) 182 #define test_syscall_work(fl) \ 183 test_ti_thread_flag(current_thread_info(), TIF_##fl) 184 #define clear_syscall_work(fl) \ 185 clear_ti_thread_flag(current_thread_info(), TIF_##fl) 186 187 #define set_task_syscall_work(t, fl) \ 188 set_ti_thread_flag(task_thread_info(t), TIF_##fl) 189 #define test_task_syscall_work(t, fl) \ 190 test_ti_thread_flag(task_thread_info(t), TIF_##fl) 191 #define clear_task_syscall_work(t, fl) \ 192 clear_ti_thread_flag(task_thread_info(t), TIF_##fl) 193 #endif /* !CONFIG_GENERIC_ENTRY */ 194 195 #ifdef _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H 196 197 static __always_inline bool tif_test_bit(int bit) 198 { 199 return arch_test_bit(bit, 200 (unsigned long *)(¤t_thread_info()->flags)); 201 } 202 203 #else 204 205 static __always_inline bool tif_test_bit(int bit) 206 { 207 return test_bit(bit, 208 (unsigned long *)(¤t_thread_info()->flags)); 209 } 210 211 #endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H */ 212 213 static __always_inline bool tif_need_resched(void) 214 { 215 return tif_test_bit(TIF_NEED_RESCHED); 216 } 217 218 #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES 219 static inline int arch_within_stack_frames(const void * const stack, 220 const void * const stackend, 221 const void *obj, unsigned long len) 222 { 223 return 0; 224 } 225 #endif 226 227 #ifndef arch_setup_new_exec 228 static inline void arch_setup_new_exec(void) { } 229 #endif 230 231 void arch_task_cache_init(void); /* for CONFIG_SH */ 232 void arch_release_task_struct(struct task_struct *tsk); 233 int arch_dup_task_struct(struct task_struct *dst, 234 struct task_struct *src); 235 236 #endif /* __KERNEL__ */ 237 238 #endif /* _LINUX_THREAD_INFO_H */ 239