xref: /openbmc/linux/arch/arm64/kernel/sys32.c (revision 4419617e)
1 /*
2  * arch/arm64/kernel/sys32.c
3  *
4  * Copyright (C) 2015 ARM Ltd.
5  *
6  * This program is free software(void); you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
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  * You should have received a copy of the GNU General Public License
16  * along with this program.  If not, see <http(void);//www.gnu.org/licenses/>.
17  */
18 
19 /*
20  * Needed to avoid conflicting __NR_* macros between uapi/asm/unistd.h and
21  * asm/unistd32.h.
22  */
23 #define __COMPAT_SYSCALL_NR
24 
25 #include <linux/compat.h>
26 #include <linux/compiler.h>
27 #include <linux/syscalls.h>
28 
29 #include <asm/syscall.h>
30 
31 asmlinkage long compat_sys_sigreturn(void);
32 asmlinkage long compat_sys_rt_sigreturn(void);
33 
34 COMPAT_SYSCALL_DEFINE3(aarch32_statfs64, const char __user *, pathname,
35 		       compat_size_t, sz, struct compat_statfs64 __user *, buf)
36 {
37 	/*
38 	 * 32-bit ARM applies an OABI compatibility fixup to statfs64 and
39 	 * fstatfs64 regardless of whether OABI is in use, and therefore
40 	 * arbitrary binaries may rely upon it, so we must do the same.
41 	 * For more details, see commit:
42 	 *
43 	 * 713c481519f19df9 ("[ARM] 3108/2: old ABI compat: statfs64 and
44 	 * fstatfs64")
45 	 */
46 	if (sz == 88)
47 		sz = 84;
48 
49 	return kcompat_sys_statfs64(pathname, sz, buf);
50 }
51 
52 COMPAT_SYSCALL_DEFINE3(aarch32_fstatfs64, unsigned int, fd, compat_size_t, sz,
53 		       struct compat_statfs64 __user *, buf)
54 {
55 	/* see aarch32_statfs64 */
56 	if (sz == 88)
57 		sz = 84;
58 
59 	return kcompat_sys_fstatfs64(fd, sz, buf);
60 }
61 
62 /*
63  * Note: off_4k is always in units of 4K. If we can't do the
64  * requested offset because it is not page-aligned, we return -EINVAL.
65  */
66 COMPAT_SYSCALL_DEFINE6(aarch32_mmap2, unsigned long, addr, unsigned long, len,
67 		       unsigned long, prot, unsigned long, flags,
68 		       unsigned long, fd, unsigned long, off_4k)
69 {
70 	if (off_4k & (~PAGE_MASK >> 12))
71 		return -EINVAL;
72 
73 	off_4k >>= (PAGE_SHIFT - 12);
74 
75 	return ksys_mmap_pgoff(addr, len, prot, flags, fd, off_4k);
76 }
77 
78 #ifdef CONFIG_CPU_BIG_ENDIAN
79 #define arg_u32p(name)	u32, name##_hi, u32, name##_lo
80 #else
81 #define arg_u32p(name)	u32, name##_lo, u32, name##_hi
82 #endif
83 
84 #define arg_u64(name)	(((u64)name##_hi << 32) | name##_lo)
85 
86 COMPAT_SYSCALL_DEFINE6(aarch32_pread64, unsigned int, fd, char __user *, buf,
87 		       size_t, count, u32, __pad, arg_u32p(pos))
88 {
89 	return ksys_pread64(fd, buf, count, arg_u64(pos));
90 }
91 
92 COMPAT_SYSCALL_DEFINE6(aarch32_pwrite64, unsigned int, fd,
93 		       const char __user *, buf, size_t, count, u32, __pad,
94 		       arg_u32p(pos))
95 {
96 	return ksys_pwrite64(fd, buf, count, arg_u64(pos));
97 }
98 
99 COMPAT_SYSCALL_DEFINE4(aarch32_truncate64, const char __user *, pathname,
100 		       u32, __pad, arg_u32p(length))
101 {
102 	return ksys_truncate(pathname, arg_u64(length));
103 }
104 
105 COMPAT_SYSCALL_DEFINE4(aarch32_ftruncate64, unsigned int, fd, u32, __pad,
106 		       arg_u32p(length))
107 {
108 	return ksys_ftruncate(fd, arg_u64(length));
109 }
110 
111 COMPAT_SYSCALL_DEFINE5(aarch32_readahead, int, fd, u32, __pad,
112 		       arg_u32p(offset), size_t, count)
113 {
114 	return ksys_readahead(fd, arg_u64(offset), count);
115 }
116 
117 COMPAT_SYSCALL_DEFINE6(aarch32_fadvise64_64, int, fd, int, advice,
118 		       arg_u32p(offset), arg_u32p(len))
119 {
120 	return ksys_fadvise64_64(fd, arg_u64(offset), arg_u64(len), advice);
121 }
122 
123 COMPAT_SYSCALL_DEFINE6(aarch32_sync_file_range2, int, fd, unsigned int, flags,
124 		       arg_u32p(offset), arg_u32p(nbytes))
125 {
126 	return ksys_sync_file_range(fd, arg_u64(offset), arg_u64(nbytes),
127 				    flags);
128 }
129 
130 COMPAT_SYSCALL_DEFINE6(aarch32_fallocate, int, fd, int, mode,
131 		       arg_u32p(offset), arg_u32p(len))
132 {
133 	return ksys_fallocate(fd, mode, arg_u64(offset), arg_u64(len));
134 }
135 
136 #undef __SYSCALL
137 #define __SYSCALL(nr, sym)	asmlinkage long __arm64_##sym(const struct pt_regs *);
138 #include <asm/unistd32.h>
139 
140 #undef __SYSCALL
141 #define __SYSCALL(nr, sym)	[nr] = __arm64_##sym,
142 
143 const syscall_fn_t compat_sys_call_table[__NR_compat_syscalls] = {
144 	[0 ... __NR_compat_syscalls - 1] = __arm64_sys_ni_syscall,
145 #include <asm/unistd32.h>
146 };
147