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	mov	x27, #0		// prevent syscall restart handling (why)
36	b	compat_sys_sigreturn
37ENDPROC(compat_sys_sigreturn_wrapper)
38
39ENTRY(compat_sys_rt_sigreturn_wrapper)
40	mov	x0, sp
41	mov	x27, #0		// prevent syscall restart handling (why)
42	b	compat_sys_rt_sigreturn
43ENDPROC(compat_sys_rt_sigreturn_wrapper)
44
45ENTRY(compat_sys_statfs64_wrapper)
46	mov	w3, #84
47	cmp	w1, #88
48	csel	w1, w3, w1, eq
49	b	compat_sys_statfs64
50ENDPROC(compat_sys_statfs64_wrapper)
51
52ENTRY(compat_sys_fstatfs64_wrapper)
53	mov	w3, #84
54	cmp	w1, #88
55	csel	w1, w3, w1, eq
56	b	compat_sys_fstatfs64
57ENDPROC(compat_sys_fstatfs64_wrapper)
58
59/*
60 * Note: off_4k (w5) is always in units of 4K. If we can't do the
61 * requested offset because it is not page-aligned, we return -EINVAL.
62 */
63ENTRY(compat_sys_mmap2_wrapper)
64#if PAGE_SHIFT > 12
65	tst	w5, #~PAGE_MASK >> 12
66	b.ne	1f
67	lsr	w5, w5, #PAGE_SHIFT - 12
68#endif
69	b	sys_mmap_pgoff
701:	mov	x0, #-EINVAL
71	ret
72ENDPROC(compat_sys_mmap2_wrapper)
73
74/*
75 * Wrappers for AArch32 syscalls that either take 64-bit parameters
76 * in registers or that take 32-bit parameters which require sign
77 * extension.
78 */
79ENTRY(compat_sys_pread64_wrapper)
80	regs_to_64	x3, x4, x5
81	b	sys_pread64
82ENDPROC(compat_sys_pread64_wrapper)
83
84ENTRY(compat_sys_pwrite64_wrapper)
85	regs_to_64	x3, x4, x5
86	b	sys_pwrite64
87ENDPROC(compat_sys_pwrite64_wrapper)
88
89ENTRY(compat_sys_truncate64_wrapper)
90	regs_to_64	x1, x2, x3
91	b	sys_truncate
92ENDPROC(compat_sys_truncate64_wrapper)
93
94ENTRY(compat_sys_ftruncate64_wrapper)
95	regs_to_64	x1, x2, x3
96	b	sys_ftruncate
97ENDPROC(compat_sys_ftruncate64_wrapper)
98
99ENTRY(compat_sys_readahead_wrapper)
100	regs_to_64	x1, x2, x3
101	mov	w2, w4
102	b	sys_readahead
103ENDPROC(compat_sys_readahead_wrapper)
104
105ENTRY(compat_sys_fadvise64_64_wrapper)
106	mov	w6, w1
107	regs_to_64	x1, x2, x3
108	regs_to_64	x2, x4, x5
109	mov	w3, w6
110	b	sys_fadvise64_64
111ENDPROC(compat_sys_fadvise64_64_wrapper)
112
113ENTRY(compat_sys_sync_file_range2_wrapper)
114	regs_to_64	x2, x2, x3
115	regs_to_64	x3, x4, x5
116	b	sys_sync_file_range2
117ENDPROC(compat_sys_sync_file_range2_wrapper)
118
119ENTRY(compat_sys_fallocate_wrapper)
120	regs_to_64	x2, x2, x3
121	regs_to_64	x3, x4, x5
122	b	sys_fallocate
123ENDPROC(compat_sys_fallocate_wrapper)
124