1/*
2 * Compat system call wrappers
3 *
4 * Copyright (C) 2012 ARM Ltd.
5 * Authors: Will Deacon <will.deacon@arm.com>
6 *	    Catalin Marinas <catalin.marinas@arm.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
19 */
20
21#include <linux/linkage.h>
22#include <linux/const.h>
23
24#include <asm/assembler.h>
25#include <asm/asm-offsets.h>
26#include <asm/errno.h>
27#include <asm/page.h>
28
29/*
30 * System call wrappers for the AArch32 compatibility layer.
31 */
32
33ENTRY(compat_sys_sigreturn_wrapper)
34	mov	x0, sp
35	b	compat_sys_sigreturn
36ENDPROC(compat_sys_sigreturn_wrapper)
37
38ENTRY(compat_sys_rt_sigreturn_wrapper)
39	mov	x0, sp
40	b	compat_sys_rt_sigreturn
41ENDPROC(compat_sys_rt_sigreturn_wrapper)
42
43ENTRY(compat_sys_statfs64_wrapper)
44	mov	w3, #84
45	cmp	w1, #88
46	csel	w1, w3, w1, eq
47	b	compat_sys_statfs64
48ENDPROC(compat_sys_statfs64_wrapper)
49
50ENTRY(compat_sys_fstatfs64_wrapper)
51	mov	w3, #84
52	cmp	w1, #88
53	csel	w1, w3, w1, eq
54	b	compat_sys_fstatfs64
55ENDPROC(compat_sys_fstatfs64_wrapper)
56
57/*
58 * Note: off_4k (w5) is always in units of 4K. If we can't do the
59 * requested offset because it is not page-aligned, we return -EINVAL.
60 */
61ENTRY(compat_sys_mmap2_wrapper)
62#if PAGE_SHIFT > 12
63	tst	w5, #~PAGE_MASK >> 12
64	b.ne	1f
65	lsr	w5, w5, #PAGE_SHIFT - 12
66#endif
67	b	sys_mmap_pgoff
681:	mov	x0, #-EINVAL
69	ret
70ENDPROC(compat_sys_mmap2_wrapper)
71
72/*
73 * Wrappers for AArch32 syscalls that either take 64-bit parameters
74 * in registers or that take 32-bit parameters which require sign
75 * extension.
76 */
77ENTRY(compat_sys_pread64_wrapper)
78	regs_to_64	x3, x4, x5
79	b	sys_pread64
80ENDPROC(compat_sys_pread64_wrapper)
81
82ENTRY(compat_sys_pwrite64_wrapper)
83	regs_to_64	x3, x4, x5
84	b	sys_pwrite64
85ENDPROC(compat_sys_pwrite64_wrapper)
86
87ENTRY(compat_sys_truncate64_wrapper)
88	regs_to_64	x1, x2, x3
89	b	sys_truncate
90ENDPROC(compat_sys_truncate64_wrapper)
91
92ENTRY(compat_sys_ftruncate64_wrapper)
93	regs_to_64	x1, x2, x3
94	b	sys_ftruncate
95ENDPROC(compat_sys_ftruncate64_wrapper)
96
97ENTRY(compat_sys_readahead_wrapper)
98	regs_to_64	x1, x2, x3
99	mov	w2, w4
100	b	sys_readahead
101ENDPROC(compat_sys_readahead_wrapper)
102
103ENTRY(compat_sys_fadvise64_64_wrapper)
104	mov	w6, w1
105	regs_to_64	x1, x2, x3
106	regs_to_64	x2, x4, x5
107	mov	w3, w6
108	b	sys_fadvise64_64
109ENDPROC(compat_sys_fadvise64_64_wrapper)
110
111ENTRY(compat_sys_sync_file_range2_wrapper)
112	regs_to_64	x2, x2, x3
113	regs_to_64	x3, x4, x5
114	b	sys_sync_file_range2
115ENDPROC(compat_sys_sync_file_range2_wrapper)
116
117ENTRY(compat_sys_fallocate_wrapper)
118	regs_to_64	x2, x2, x3
119	regs_to_64	x3, x4, x5
120	b	sys_fallocate
121ENDPROC(compat_sys_fallocate_wrapper)
122