1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * arch/arm64/kernel/sys32.c
4 *
5 * Copyright (C) 2015 ARM Ltd.
6 */
7
8/*
9 * Needed to avoid conflicting __NR_* macros between uapi/asm/unistd.h and
10 * asm/unistd32.h.
11 */
12#define __COMPAT_SYSCALL_NR
13
14#include <linux/compat.h>
15#include <linux/compiler.h>
16#include <linux/syscalls.h>
17
18#include <asm/syscall.h>
19
20asmlinkage long compat_sys_sigreturn(void);
21asmlinkage long compat_sys_rt_sigreturn(void);
22
23COMPAT_SYSCALL_DEFINE3(aarch32_statfs64, const char __user *, pathname,
24		       compat_size_t, sz, struct compat_statfs64 __user *, buf)
25{
26	/*
27	 * 32-bit ARM applies an OABI compatibility fixup to statfs64 and
28	 * fstatfs64 regardless of whether OABI is in use, and therefore
29	 * arbitrary binaries may rely upon it, so we must do the same.
30	 * For more details, see commit:
31	 *
32	 * 713c481519f19df9 ("[ARM] 3108/2: old ABI compat: statfs64 and
33	 * fstatfs64")
34	 */
35	if (sz == 88)
36		sz = 84;
37
38	return kcompat_sys_statfs64(pathname, sz, buf);
39}
40
41COMPAT_SYSCALL_DEFINE3(aarch32_fstatfs64, unsigned int, fd, compat_size_t, sz,
42		       struct compat_statfs64 __user *, buf)
43{
44	/* see aarch32_statfs64 */
45	if (sz == 88)
46		sz = 84;
47
48	return kcompat_sys_fstatfs64(fd, sz, buf);
49}
50
51/*
52 * Note: off_4k is always in units of 4K. If we can't do the
53 * requested offset because it is not page-aligned, we return -EINVAL.
54 */
55COMPAT_SYSCALL_DEFINE6(aarch32_mmap2, unsigned long, addr, unsigned long, len,
56		       unsigned long, prot, unsigned long, flags,
57		       unsigned long, fd, unsigned long, off_4k)
58{
59	if (off_4k & (~PAGE_MASK >> 12))
60		return -EINVAL;
61
62	off_4k >>= (PAGE_SHIFT - 12);
63
64	return ksys_mmap_pgoff(addr, len, prot, flags, fd, off_4k);
65}
66
67#ifdef CONFIG_CPU_BIG_ENDIAN
68#define arg_u32p(name)	u32, name##_hi, u32, name##_lo
69#else
70#define arg_u32p(name)	u32, name##_lo, u32, name##_hi
71#endif
72
73#define arg_u64(name)	(((u64)name##_hi << 32) | name##_lo)
74
75COMPAT_SYSCALL_DEFINE6(aarch32_pread64, unsigned int, fd, char __user *, buf,
76		       size_t, count, u32, __pad, arg_u32p(pos))
77{
78	return ksys_pread64(fd, buf, count, arg_u64(pos));
79}
80
81COMPAT_SYSCALL_DEFINE6(aarch32_pwrite64, unsigned int, fd,
82		       const char __user *, buf, size_t, count, u32, __pad,
83		       arg_u32p(pos))
84{
85	return ksys_pwrite64(fd, buf, count, arg_u64(pos));
86}
87
88COMPAT_SYSCALL_DEFINE4(aarch32_truncate64, const char __user *, pathname,
89		       u32, __pad, arg_u32p(length))
90{
91	return ksys_truncate(pathname, arg_u64(length));
92}
93
94COMPAT_SYSCALL_DEFINE4(aarch32_ftruncate64, unsigned int, fd, u32, __pad,
95		       arg_u32p(length))
96{
97	return ksys_ftruncate(fd, arg_u64(length));
98}
99
100COMPAT_SYSCALL_DEFINE5(aarch32_readahead, int, fd, u32, __pad,
101		       arg_u32p(offset), size_t, count)
102{
103	return ksys_readahead(fd, arg_u64(offset), count);
104}
105
106COMPAT_SYSCALL_DEFINE6(aarch32_fadvise64_64, int, fd, int, advice,
107		       arg_u32p(offset), arg_u32p(len))
108{
109	return ksys_fadvise64_64(fd, arg_u64(offset), arg_u64(len), advice);
110}
111
112COMPAT_SYSCALL_DEFINE6(aarch32_sync_file_range2, int, fd, unsigned int, flags,
113		       arg_u32p(offset), arg_u32p(nbytes))
114{
115	return ksys_sync_file_range(fd, arg_u64(offset), arg_u64(nbytes),
116				    flags);
117}
118
119COMPAT_SYSCALL_DEFINE6(aarch32_fallocate, int, fd, int, mode,
120		       arg_u32p(offset), arg_u32p(len))
121{
122	return ksys_fallocate(fd, mode, arg_u64(offset), arg_u64(len));
123}
124
125#undef __SYSCALL
126#define __SYSCALL(nr, sym)	asmlinkage long __arm64_##sym(const struct pt_regs *);
127#include <asm/unistd32.h>
128
129#undef __SYSCALL
130#define __SYSCALL(nr, sym)	[nr] = __arm64_##sym,
131
132const syscall_fn_t compat_sys_call_table[__NR_compat_syscalls] = {
133	[0 ... __NR_compat_syscalls - 1] = __arm64_sys_ni_syscall,
134#include <asm/unistd32.h>
135};
136