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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_ENTRYCOMMON_H
#define __LINUX_ENTRYCOMMON_H
#include <linux/tracehook.h>
#include <linux/syscalls.h>
#include <linux/seccomp.h>
#include <linux/sched.h>
#include <asm/entry-common.h>
/*
* Define dummy _TIF work flags if not defined by the architecture or for
* disabled functionality.
*/
#ifndef _TIF_SYSCALL_EMU
# define _TIF_SYSCALL_EMU (0)
#endif
#ifndef _TIF_SYSCALL_TRACEPOINT
# define _TIF_SYSCALL_TRACEPOINT (0)
#endif
#ifndef _TIF_SECCOMP
# define _TIF_SECCOMP (0)
#endif
#ifndef _TIF_SYSCALL_AUDIT
# define _TIF_SYSCALL_AUDIT (0)
#endif
/*
* TIF flags handled in syscall_enter_from_usermode()
*/
#ifndef ARCH_SYSCALL_ENTER_WORK
# define ARCH_SYSCALL_ENTER_WORK (0)
#endif
#define SYSCALL_ENTER_WORK \
(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
_TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_EMU | \
ARCH_SYSCALL_ENTER_WORK)
/**
* arch_check_user_regs - Architecture specific sanity check for user mode regs
* @regs: Pointer to currents pt_regs
*
* Defaults to an empty implementation. Can be replaced by architecture
* specific code.
*
* Invoked from syscall_enter_from_user_mode() in the non-instrumentable
* section. Use __always_inline so the compiler cannot push it out of line
* and make it instrumentable.
*/
static __always_inline void arch_check_user_regs(struct pt_regs *regs);
#ifndef arch_check_user_regs
static __always_inline void arch_check_user_regs(struct pt_regs *regs) {}
#endif
/**
* arch_syscall_enter_tracehook - Wrapper around tracehook_report_syscall_entry()
* @regs: Pointer to currents pt_regs
*
* Returns: 0 on success or an error code to skip the syscall.
*
* Defaults to tracehook_report_syscall_entry(). Can be replaced by
* architecture specific code.
*
* Invoked from syscall_enter_from_user_mode()
*/
static inline __must_check int arch_syscall_enter_tracehook(struct pt_regs *regs);
#ifndef arch_syscall_enter_tracehook
static inline __must_check int arch_syscall_enter_tracehook(struct pt_regs *regs)
{
return tracehook_report_syscall_entry(regs);
}
#endif
/**
* syscall_enter_from_user_mode - 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 and the subsequent functions can be
* instrumented.
*
* Returns: The original or a modified syscall number
*
* If the returned syscall number is -1 then the syscall should be
* skipped. In this case the caller may invoke syscall_set_error() or
* 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:
*
* 1) Establish state (lockdep, RCU (context tracking), tracing)
* 2) TIF flag dependent invocations of arch_syscall_enter_tracehook(),
* __secure_computing(), trace_sys_enter()
* 3) Invocation of audit_syscall_entry()
*/
long syscall_enter_from_user_mode(struct pt_regs *regs, long syscall);
/**
* irqentry_enter_from_user_mode - Establish state before invoking the irq handler
* @regs: Pointer to currents pt_regs
*
* Invoked from architecture specific entry code with interrupts disabled.
* Can only be called when the interrupt entry came from user mode. The
* calling code must be non-instrumentable. When the function returns all
* state is correct and the subsequent functions can be instrumented.
*
* The function establishes state (lockdep, RCU (context tracking), tracing)
*/
void irqentry_enter_from_user_mode(struct pt_regs *regs);
#endif
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