/*
 * eset_rtp (ESET Real-time file system protection module)
 * Copyright (C) 1992-2023 ESET, spol. s r.o.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 *
 * In case of any questions, you can contact us at ESET, spol. s r.o., Einsteinova 24, 851 01 Bratislava, Slovakia.
 */

#ifndef _ERTP_HANDLERS_H_
#define _ERTP_HANDLERS_H_

#include <linux/cred.h>
#include <linux/mman.h>
#include <linux/syscalls.h>
#include <linux/version.h>

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4, 17, 0))
#define ERTP_KERNEL_USES_SYSCALL_WRAPPER 1
#endif

#ifdef ERTP_KERNEL_USES_SYSCALL_WRAPPER
#include <asm/syscall.h>
#include <asm/syscall_wrapper.h>
#endif

#ifdef CONFIG_COMPAT
#include <linux/compat.h>
#endif

int ertp_handlers_init(void);
void ertp_handlers_deinit(void);

#ifdef ERTP_KERNEL_USES_SYSCALL_WRAPPER

typedef asmlinkage long (*sys_regs_t)(const struct pt_regs *regs);
#endif

extern atomic_t ertp_running_syscalls_counter;
extern wait_queue_head_t ertp_syscall_handlers_unregister_wait;

static inline void ertp_handler_start(void) {
  atomic_inc(&ertp_running_syscalls_counter);
}

static inline void ertp_handler_end(void) {
  if (unlikely(atomic_dec_and_test(&ertp_running_syscalls_counter))) {
    wake_up(&ertp_syscall_handlers_unregister_wait);
  }
}

#endif