diff options
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/entry-common.h | 51 |
1 files changed, 42 insertions, 9 deletions
diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index efebbffcd5cc..159c7476b11b 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -110,15 +110,30 @@ static inline __must_check int arch_syscall_enter_tracehook(struct pt_regs *regs #endif /** - * syscall_enter_from_user_mode - Check and handle work before invoking - * a syscall + * syscall_enter_from_user_mode_prepare - Establish state and enable interrupts * @regs: Pointer to currents pt_regs - * @syscall: The syscall number * * Invoked from architecture specific syscall entry code with interrupts * disabled. The calling code has to be non-instrumentable. When the - * function returns all state is correct and the subsequent functions can be - * instrumented. + * function returns all state is correct, interrupts are enabled and the + * subsequent functions can be instrumented. + * + * This handles lockdep, RCU (context tracking) and tracing state. + * + * This is invoked when there is extra architecture specific functionality + * to be done between establishing state and handling user mode entry work. + */ +void syscall_enter_from_user_mode_prepare(struct pt_regs *regs); + +/** + * syscall_enter_from_user_mode_work - Check and handle work before invoking + * a syscall + * @regs: Pointer to currents pt_regs + * @syscall: The syscall number + * + * Invoked from architecture specific syscall entry code with interrupts + * enabled after invoking syscall_enter_from_user_mode_prepare() and extra + * architecture specific work. * * Returns: The original or a modified syscall number * @@ -127,12 +142,30 @@ static inline __must_check int arch_syscall_enter_tracehook(struct pt_regs *regs * syscall_set_return_value() first. If neither of those are called and -1 * is returned, then the syscall will fail with ENOSYS. * - * The following functionality is handled here: + * It handles the following work items: * - * 1) Establish state (lockdep, RCU (context tracking), tracing) - * 2) TIF flag dependent invocations of arch_syscall_enter_tracehook(), + * 1) TIF flag dependent invocations of arch_syscall_enter_tracehook(), * __secure_computing(), trace_sys_enter() - * 3) Invocation of audit_syscall_entry() + * 2) Invocation of audit_syscall_entry() + */ +long syscall_enter_from_user_mode_work(struct pt_regs *regs, long syscall); + +/** + * syscall_enter_from_user_mode - Establish state and check and handle work + * before invoking a syscall + * @regs: Pointer to currents pt_regs + * @syscall: The syscall number + * + * Invoked from architecture specific syscall entry code with interrupts + * disabled. The calling code has to be non-instrumentable. When the + * function returns all state is correct, interrupts are enabled and the + * subsequent functions can be instrumented. + * + * This is combination of syscall_enter_from_user_mode_prepare() and + * syscall_enter_from_user_mode_work(). + * + * Returns: The original or a modified syscall number. See + * syscall_enter_from_user_mode_work() for further explanation. */ long syscall_enter_from_user_mode(struct pt_regs *regs, long syscall); |