xref: /linux/arch/riscv/kernel/sys_riscv.c (revision 20a2742e5784295b9197250b50c40f6d38a55880)
1 /*
2  * Copyright (C) 2012 Regents of the University of California
3  * Copyright (C) 2014 Darius Rad <darius@bluespec.com>
4  * Copyright (C) 2017 SiFive
5  *
6  *   This program is free software; you can redistribute it and/or
7  *   modify it under the terms of the GNU General Public License
8  *   as published by the Free Software Foundation, version 2.
9  *
10  *   This program is distributed in the hope that it will be useful,
11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *   GNU General Public License for more details.
14  */
15 
16 #include <linux/syscalls.h>
17 #include <asm/cmpxchg.h>
18 #include <asm/unistd.h>
19 
20 static long riscv_sys_mmap(unsigned long addr, unsigned long len,
21 			   unsigned long prot, unsigned long flags,
22 			   unsigned long fd, off_t offset,
23 			   unsigned long page_shift_offset)
24 {
25 	if (unlikely(offset & (~PAGE_MASK >> page_shift_offset)))
26 		return -EINVAL;
27 	return sys_mmap_pgoff(addr, len, prot, flags, fd,
28 			      offset >> (PAGE_SHIFT - page_shift_offset));
29 }
30 
31 #ifdef CONFIG_64BIT
32 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
33 	unsigned long, prot, unsigned long, flags,
34 	unsigned long, fd, off_t, offset)
35 {
36 	return riscv_sys_mmap(addr, len, prot, flags, fd, offset, 0);
37 }
38 #else
39 SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
40 	unsigned long, prot, unsigned long, flags,
41 	unsigned long, fd, off_t, offset)
42 {
43 	/*
44 	 * Note that the shift for mmap2 is constant (12),
45 	 * regardless of PAGE_SIZE
46 	 */
47 	return riscv_sys_mmap(addr, len, prot, flags, fd, offset, 12);
48 }
49 #endif /* !CONFIG_64BIT */
50