diff options
Diffstat (limited to 'include/linux/thread_info.h')
| -rw-r--r-- | include/linux/thread_info.h | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h new file mode 100644 index 000000000..9f392ec76 --- /dev/null +++ b/include/linux/thread_info.h @@ -0,0 +1,245 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* thread_info.h: common low-level thread information accessors + * + * Copyright (C) 2002 David Howells (dhowells@redhat.com) + * - Incorporating suggestions made by Linus Torvalds + */ + +#ifndef _LINUX_THREAD_INFO_H +#define _LINUX_THREAD_INFO_H + +#include <linux/types.h> +#include <linux/limits.h> +#include <linux/bug.h> +#include <linux/restart_block.h> +#include <linux/errno.h> + +#ifdef CONFIG_THREAD_INFO_IN_TASK +/* + * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the + * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels, + * including <asm/current.h> can cause a circular dependency on some platforms. + */ +#include <asm/current.h> +#define current_thread_info() ((struct thread_info *)current) +#endif + +#include <linux/bitops.h> + +/* + * For per-arch arch_within_stack_frames() implementations, defined in + * asm/thread_info.h. + */ +enum { + BAD_STACK = -1, + NOT_STACK = 0, + GOOD_FRAME, + GOOD_STACK, +}; + +#ifdef CONFIG_GENERIC_ENTRY +enum syscall_work_bit { + SYSCALL_WORK_BIT_SECCOMP, + SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT, + SYSCALL_WORK_BIT_SYSCALL_TRACE, + SYSCALL_WORK_BIT_SYSCALL_EMU, + SYSCALL_WORK_BIT_SYSCALL_AUDIT, + SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH, + SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP, +}; + +#define SYSCALL_WORK_SECCOMP BIT(SYSCALL_WORK_BIT_SECCOMP) +#define SYSCALL_WORK_SYSCALL_TRACEPOINT BIT(SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT) +#define SYSCALL_WORK_SYSCALL_TRACE BIT(SYSCALL_WORK_BIT_SYSCALL_TRACE) +#define SYSCALL_WORK_SYSCALL_EMU BIT(SYSCALL_WORK_BIT_SYSCALL_EMU) +#define SYSCALL_WORK_SYSCALL_AUDIT BIT(SYSCALL_WORK_BIT_SYSCALL_AUDIT) +#define SYSCALL_WORK_SYSCALL_USER_DISPATCH BIT(SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH) +#define SYSCALL_WORK_SYSCALL_EXIT_TRAP BIT(SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP) +#endif + +#include <asm/thread_info.h> + +#ifdef __KERNEL__ + +#ifndef arch_set_restart_data +#define arch_set_restart_data(restart) do { } while (0) +#endif + +static inline long set_restart_fn(struct restart_block *restart, + long (*fn)(struct restart_block *)) +{ + restart->fn = fn; + arch_set_restart_data(restart); + return -ERESTART_RESTARTBLOCK; +} + +#ifndef THREAD_ALIGN +#define THREAD_ALIGN THREAD_SIZE +#endif + +#define THREADINFO_GFP (GFP_KERNEL_ACCOUNT | __GFP_ZERO) + +/* + * flag set/clear/test wrappers + * - pass TIF_xxxx constants to these functions + */ + +static inline void set_ti_thread_flag(struct thread_info *ti, int flag) +{ + set_bit(flag, (unsigned long *)&ti->flags); +} + +static inline void clear_ti_thread_flag(struct thread_info *ti, int flag) +{ + clear_bit(flag, (unsigned long *)&ti->flags); +} + +static inline void update_ti_thread_flag(struct thread_info *ti, int flag, + bool value) +{ + if (value) + set_ti_thread_flag(ti, flag); + else + clear_ti_thread_flag(ti, flag); +} + +static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag) +{ + return test_and_set_bit(flag, (unsigned long *)&ti->flags); +} + +static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag) +{ + return test_and_clear_bit(flag, (unsigned long *)&ti->flags); +} + +static inline int test_ti_thread_flag(struct thread_info *ti, int flag) +{ + return test_bit(flag, (unsigned long *)&ti->flags); +} + +/* + * This may be used in noinstr code, and needs to be __always_inline to prevent + * inadvertent instrumentation. + */ +static __always_inline unsigned long read_ti_thread_flags(struct thread_info *ti) +{ + return READ_ONCE(ti->flags); +} + +#define set_thread_flag(flag) \ + set_ti_thread_flag(current_thread_info(), flag) +#define clear_thread_flag(flag) \ + clear_ti_thread_flag(current_thread_info(), flag) +#define update_thread_flag(flag, value) \ + update_ti_thread_flag(current_thread_info(), flag, value) +#define test_and_set_thread_flag(flag) \ + test_and_set_ti_thread_flag(current_thread_info(), flag) +#define test_and_clear_thread_flag(flag) \ + test_and_clear_ti_thread_flag(current_thread_info(), flag) +#define test_thread_flag(flag) \ + test_ti_thread_flag(current_thread_info(), flag) +#define read_thread_flags() \ + read_ti_thread_flags(current_thread_info()) + +#define read_task_thread_flags(t) \ + read_ti_thread_flags(task_thread_info(t)) + +#ifdef CONFIG_GENERIC_ENTRY +#define set_syscall_work(fl) \ + set_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) +#define test_syscall_work(fl) \ + test_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) +#define clear_syscall_work(fl) \ + clear_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work) + +#define set_task_syscall_work(t, fl) \ + set_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) +#define test_task_syscall_work(t, fl) \ + test_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) +#define clear_task_syscall_work(t, fl) \ + clear_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work) + +#else /* CONFIG_GENERIC_ENTRY */ + +#define set_syscall_work(fl) \ + set_ti_thread_flag(current_thread_info(), TIF_##fl) +#define test_syscall_work(fl) \ + test_ti_thread_flag(current_thread_info(), TIF_##fl) +#define clear_syscall_work(fl) \ + clear_ti_thread_flag(current_thread_info(), TIF_##fl) + +#define set_task_syscall_work(t, fl) \ + set_ti_thread_flag(task_thread_info(t), TIF_##fl) +#define test_task_syscall_work(t, fl) \ + test_ti_thread_flag(task_thread_info(t), TIF_##fl) +#define clear_task_syscall_work(t, fl) \ + clear_ti_thread_flag(task_thread_info(t), TIF_##fl) +#endif /* !CONFIG_GENERIC_ENTRY */ + +#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED) + +#ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES +static inline int arch_within_stack_frames(const void * const stack, + const void * const stackend, + const void *obj, unsigned long len) +{ + return 0; +} +#endif + +#ifdef CONFIG_HARDENED_USERCOPY +extern void __check_object_size(const void *ptr, unsigned long n, + bool to_user); + +static __always_inline void check_object_size(const void *ptr, unsigned long n, + bool to_user) +{ + if (!__builtin_constant_p(n)) + __check_object_size(ptr, n, to_user); +} +#else +static inline void check_object_size(const void *ptr, unsigned long n, + bool to_user) +{ } +#endif /* CONFIG_HARDENED_USERCOPY */ + +extern void __compiletime_error("copy source size is too small") +__bad_copy_from(void); +extern void __compiletime_error("copy destination size is too small") +__bad_copy_to(void); + +void __copy_overflow(int size, unsigned long count); + +static inline void copy_overflow(int size, unsigned long count) +{ + if (IS_ENABLED(CONFIG_BUG)) + __copy_overflow(size, count); +} + +static __always_inline __must_check bool +check_copy_size(const void *addr, size_t bytes, bool is_source) +{ + int sz = __builtin_object_size(addr, 0); + if (unlikely(sz >= 0 && sz < bytes)) { + if (!__builtin_constant_p(bytes)) + copy_overflow(sz, bytes); + else if (is_source) + __bad_copy_from(); + else + __bad_copy_to(); + return false; + } + if (WARN_ON_ONCE(bytes > INT_MAX)) + return false; + check_object_size(addr, bytes, is_source); + return true; +} + +#ifndef arch_setup_new_exec +static inline void arch_setup_new_exec(void) { } +#endif + +#endif /* __KERNEL__ */ + +#endif /* _LINUX_THREAD_INFO_H */ |