tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
arm64: System calls handling
This patch adds support for system calls coming from 64-bit
applications. It uses the asm-generic/unistd.h definitions with the
canonical set of system calls. The private system calls are only used
for 32-bit (compat) applications as 64-bit ones can set the TLS and
flush the caches entirely from user space.
The sys_call_table is just an array defined in a C file and it contains
pointers to the syscall functions. The array is 4KB aligned to allow the
use of the ADRP instruction (longer range ADR) in entry.S.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
+290
+62
arch/arm64/include/asm/stat.h
+62
arch/arm64/include/asm/stat.h
···
1
+
/*
2
+
* Copyright (C) 2012 ARM Ltd.
3
+
*
4
+
* This program is free software; you can redistribute it and/or modify
5
+
* it under the terms of the GNU General Public License version 2 as
6
+
* published by the Free Software Foundation.
7
+
*
8
+
* This program is distributed in the hope that it will be useful,
9
+
* but WITHOUT ANY WARRANTY; without even the implied warranty of
10
+
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
+
* GNU General Public License for more details.
12
+
*
13
+
* You should have received a copy of the GNU General Public License
14
+
* along with this program. If not, see <http://www.gnu.org/licenses/>.
15
+
*/
16
+
#ifndef __ASM_STAT_H
17
+
#define __ASM_STAT_H
18
+
19
+
#include <asm-generic/stat.h>
20
+
21
+
#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
22
+
23
+
#include <asm/compat.h>
24
+
25
+
/*
26
+
* struct stat64 is needed for compat tasks only. Its definition is different
27
+
* from the generic struct stat64.
28
+
*/
29
+
struct stat64 {
30
+
compat_u64 st_dev;
31
+
unsigned char __pad0[4];
32
+
33
+
#define STAT64_HAS_BROKEN_ST_INO 1
34
+
compat_ulong_t __st_ino;
35
+
compat_uint_t st_mode;
36
+
compat_uint_t st_nlink;
37
+
38
+
compat_ulong_t st_uid;
39
+
compat_ulong_t st_gid;
40
+
41
+
compat_u64 st_rdev;
42
+
unsigned char __pad3[4];
43
+
44
+
compat_s64 st_size;
45
+
compat_ulong_t st_blksize;
46
+
compat_u64 st_blocks; /* Number of 512-byte blocks allocated. */
47
+
48
+
compat_ulong_t st_atime;
49
+
compat_ulong_t st_atime_nsec;
50
+
51
+
compat_ulong_t st_mtime;
52
+
compat_ulong_t st_mtime_nsec;
53
+
54
+
compat_ulong_t st_ctime;
55
+
compat_ulong_t st_ctime_nsec;
56
+
57
+
compat_u64 st_ino;
58
+
};
59
+
60
+
#endif
61
+
62
+
#endif
+23
arch/arm64/include/asm/statfs.h
+23
arch/arm64/include/asm/statfs.h
···
1
+
/*
2
+
* Copyright (C) 2012 ARM Ltd.
3
+
*
4
+
* This program is free software; you can redistribute it and/or modify
5
+
* it under the terms of the GNU General Public License version 2 as
6
+
* published by the Free Software Foundation.
7
+
*
8
+
* This program is distributed in the hope that it will be useful,
9
+
* but WITHOUT ANY WARRANTY; without even the implied warranty of
10
+
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
+
* GNU General Public License for more details.
12
+
*
13
+
* You should have received a copy of the GNU General Public License
14
+
* along with this program. If not, see <http://www.gnu.org/licenses/>.
15
+
*/
16
+
#ifndef __ASM_STATFS_H
17
+
#define __ASM_STATFS_H
18
+
19
+
#define ARCH_PACK_COMPAT_STATFS64 __attribute__((packed,aligned(4)))
20
+
21
+
#include <asm-generic/statfs.h>
22
+
23
+
#endif
+40
arch/arm64/include/asm/syscalls.h
+40
arch/arm64/include/asm/syscalls.h
···
1
+
/*
2
+
* Copyright (C) 2012 ARM Ltd.
3
+
*
4
+
* This program is free software; you can redistribute it and/or modify
5
+
* it under the terms of the GNU General Public License version 2 as
6
+
* published by the Free Software Foundation.
7
+
*
8
+
* This program is distributed in the hope that it will be useful,
9
+
* but WITHOUT ANY WARRANTY; without even the implied warranty of
10
+
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
+
* GNU General Public License for more details.
12
+
*
13
+
* You should have received a copy of the GNU General Public License
14
+
* along with this program. If not, see <http://www.gnu.org/licenses/>.
15
+
*/
16
+
#ifndef __ASM_SYSCALLS_H
17
+
#define __ASM_SYSCALLS_H
18
+
19
+
#include <linux/linkage.h>
20
+
#include <linux/compiler.h>
21
+
#include <linux/signal.h>
22
+
23
+
/*
24
+
* System call wrappers implemented in kernel/entry.S.
25
+
*/
26
+
asmlinkage long sys_execve_wrapper(const char __user *filename,
27
+
const char __user *const __user *argv,
28
+
const char __user *const __user *envp);
29
+
asmlinkage long sys_clone_wrapper(unsigned long clone_flags,
30
+
unsigned long newsp,
31
+
void __user *parent_tid,
32
+
unsigned long tls_val,
33
+
void __user *child_tid);
34
+
asmlinkage long sys_rt_sigreturn_wrapper(void);
35
+
asmlinkage long sys_sigaltstack_wrapper(const stack_t __user *uss,
36
+
stack_t __user *uoss);
37
+
38
+
#include <asm-generic/syscalls.h>
39
+
40
+
#endif /* __ASM_SYSCALLS_H */
+27
arch/arm64/include/asm/unistd.h
+27
arch/arm64/include/asm/unistd.h
···
1
+
/*
2
+
* Copyright (C) 2012 ARM Ltd.
3
+
*
4
+
* This program is free software; you can redistribute it and/or modify
5
+
* it under the terms of the GNU General Public License version 2 as
6
+
* published by the Free Software Foundation.
7
+
*
8
+
* This program is distributed in the hope that it will be useful,
9
+
* but WITHOUT ANY WARRANTY; without even the implied warranty of
10
+
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
+
* GNU General Public License for more details.
12
+
*
13
+
* You should have received a copy of the GNU General Public License
14
+
* along with this program. If not, see <http://www.gnu.org/licenses/>.
15
+
*/
16
+
#if !defined(__ASM_UNISTD_H) || defined(__SYSCALL)
17
+
#define __ASM_UNISTD_H
18
+
19
+
#ifndef __SYSCALL_COMPAT
20
+
#include <asm-generic/unistd.h>
21
+
#endif
22
+
23
+
#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
24
+
#include <asm/unistd32.h>
25
+
#endif
26
+
27
+
#endif /* __ASM_UNISTD_H */
+138
arch/arm64/kernel/sys.c
+138
arch/arm64/kernel/sys.c
···
1
+
/*
2
+
* AArch64-specific system calls implementation
3
+
*
4
+
* Copyright (C) 2012 ARM Ltd.
5
+
* Author: Catalin Marinas <catalin.marinas@arm.com>
6
+
*
7
+
* This program is free software; you can redistribute it and/or modify
8
+
* it under the terms of the GNU General Public License version 2 as
9
+
* published by the Free Software Foundation.
10
+
*
11
+
* This program is distributed in the hope that it will be useful,
12
+
* but WITHOUT ANY WARRANTY; without even the implied warranty of
13
+
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14
+
* GNU General Public License for more details.
15
+
*
16
+
* You should have received a copy of the GNU General Public License
17
+
* along with this program. If not, see <http://www.gnu.org/licenses/>.
18
+
*/
19
+
20
+
#include <linux/compiler.h>
21
+
#include <linux/errno.h>
22
+
#include <linux/fs.h>
23
+
#include <linux/mm.h>
24
+
#include <linux/export.h>
25
+
#include <linux/sched.h>
26
+
#include <linux/slab.h>
27
+
#include <linux/syscalls.h>
28
+
29
+
/*
30
+
* Clone a task - this clones the calling program thread.
31
+
*/
32
+
asmlinkage long sys_clone(unsigned long clone_flags, unsigned long newsp,
33
+
int __user *parent_tidptr, unsigned long tls_val,
34
+
int __user *child_tidptr, struct pt_regs *regs)
35
+
{
36
+
if (!newsp)
37
+
newsp = regs->sp;
38
+
/* 16-byte aligned stack mandatory on AArch64 */
39
+
if (newsp & 15)
40
+
return -EINVAL;
41
+
return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
42
+
}
43
+
44
+
/*
45
+
* sys_execve() executes a new program.
46
+
*/
47
+
asmlinkage long sys_execve(const char __user *filenamei,
48
+
const char __user *const __user *argv,
49
+
const char __user *const __user *envp,
50
+
struct pt_regs *regs)
51
+
{
52
+
long error;
53
+
char * filename;
54
+
55
+
filename = getname(filenamei);
56
+
error = PTR_ERR(filename);
57
+
if (IS_ERR(filename))
58
+
goto out;
59
+
error = do_execve(filename, argv, envp, regs);
60
+
putname(filename);
61
+
out:
62
+
return error;
63
+
}
64
+
65
+
int kernel_execve(const char *filename,
66
+
const char *const argv[],
67
+
const char *const envp[])
68
+
{
69
+
struct pt_regs regs;
70
+
int ret;
71
+
72
+
memset(®s, 0, sizeof(struct pt_regs));
73
+
ret = do_execve(filename,
74
+
(const char __user *const __user *)argv,
75
+
(const char __user *const __user *)envp, ®s);
76
+
if (ret < 0)
77
+
goto out;
78
+
79
+
/*
80
+
* Save argc to the register structure for userspace.
81
+
*/
82
+
regs.regs[0] = ret;
83
+
84
+
/*
85
+
* We were successful. We won't be returning to our caller, but
86
+
* instead to user space by manipulating the kernel stack.
87
+
*/
88
+
asm( "add x0, %0, %1\n\t"
89
+
"mov x1, %2\n\t"
90
+
"mov x2, %3\n\t"
91
+
"bl memmove\n\t" /* copy regs to top of stack */
92
+
"mov x27, #0\n\t" /* not a syscall */
93
+
"mov x28, %0\n\t" /* thread structure */
94
+
"mov sp, x0\n\t" /* reposition stack pointer */
95
+
"b ret_to_user"
96
+
:
97
+
: "r" (current_thread_info()),
98
+
"Ir" (THREAD_START_SP - sizeof(regs)),
99
+
"r" (®s),
100
+
"Ir" (sizeof(regs))
101
+
: "x0", "x1", "x2", "x27", "x28", "x30", "memory");
102
+
103
+
out:
104
+
return ret;
105
+
}
106
+
EXPORT_SYMBOL(kernel_execve);
107
+
108
+
asmlinkage long sys_mmap(unsigned long addr, unsigned long len,
109
+
unsigned long prot, unsigned long flags,
110
+
unsigned long fd, off_t off)
111
+
{
112
+
if (offset_in_page(off) != 0)
113
+
return -EINVAL;
114
+
115
+
return sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
116
+
}
117
+
118
+
/*
119
+
* Wrappers to pass the pt_regs argument.
120
+
*/
121
+
#define sys_execve sys_execve_wrapper
122
+
#define sys_clone sys_clone_wrapper
123
+
#define sys_rt_sigreturn sys_rt_sigreturn_wrapper
124
+
#define sys_sigaltstack sys_sigaltstack_wrapper
125
+
126
+
#include <asm/syscalls.h>
127
+
128
+
#undef __SYSCALL
129
+
#define __SYSCALL(nr, sym) [nr] = sym,
130
+
131
+
/*
132
+
* The sys_call_table array must be 4K aligned to be accessible from
133
+
* kernel/entry.S.
134
+
*/
135
+
void *sys_call_table[__NR_syscalls] __aligned(4096) = {
136
+
[0 ... __NR_syscalls - 1] = sys_ni_syscall,
137
+
#include <asm/unistd.h>
138
+
};