Commit 7992d60d authored by Catalin Marinas's avatar Catalin Marinas

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: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Acked-by: default avatarTony Lindgren <tony@atomide.com>
Acked-by: default avatarNicolas Pitre <nico@linaro.org>
Acked-by: default avatarOlof Johansson <olof@lixom.net>
Acked-by: default avatarSantosh Shilimkar <santosh.shilimkar@ti.com>
parent f668cd16
/*
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_STAT_H
#define __ASM_STAT_H
#include <asm-generic/stat.h>
#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
#include <asm/compat.h>
/*
* struct stat64 is needed for compat tasks only. Its definition is different
* from the generic struct stat64.
*/
struct stat64 {
compat_u64 st_dev;
unsigned char __pad0[4];
#define STAT64_HAS_BROKEN_ST_INO 1
compat_ulong_t __st_ino;
compat_uint_t st_mode;
compat_uint_t st_nlink;
compat_ulong_t st_uid;
compat_ulong_t st_gid;
compat_u64 st_rdev;
unsigned char __pad3[4];
compat_s64 st_size;
compat_ulong_t st_blksize;
compat_u64 st_blocks; /* Number of 512-byte blocks allocated. */
compat_ulong_t st_atime;
compat_ulong_t st_atime_nsec;
compat_ulong_t st_mtime;
compat_ulong_t st_mtime_nsec;
compat_ulong_t st_ctime;
compat_ulong_t st_ctime_nsec;
compat_u64 st_ino;
};
#endif
#endif
/*
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_STATFS_H
#define __ASM_STATFS_H
#define ARCH_PACK_COMPAT_STATFS64 __attribute__((packed,aligned(4)))
#include <asm-generic/statfs.h>
#endif
/*
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_SYSCALLS_H
#define __ASM_SYSCALLS_H
#include <linux/linkage.h>
#include <linux/compiler.h>
#include <linux/signal.h>
/*
* System call wrappers implemented in kernel/entry.S.
*/
asmlinkage long sys_execve_wrapper(const char __user *filename,
const char __user *const __user *argv,
const char __user *const __user *envp);
asmlinkage long sys_clone_wrapper(unsigned long clone_flags,
unsigned long newsp,
void __user *parent_tid,
unsigned long tls_val,
void __user *child_tid);
asmlinkage long sys_rt_sigreturn_wrapper(void);
asmlinkage long sys_sigaltstack_wrapper(const stack_t __user *uss,
stack_t __user *uoss);
#include <asm-generic/syscalls.h>
#endif /* __ASM_SYSCALLS_H */
/*
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#if !defined(__ASM_UNISTD_H) || defined(__SYSCALL)
#define __ASM_UNISTD_H
#ifndef __SYSCALL_COMPAT
#include <asm-generic/unistd.h>
#endif
#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
#include <asm/unistd32.h>
#endif
#endif /* __ASM_UNISTD_H */
/*
* AArch64-specific system calls implementation
*
* Copyright (C) 2012 ARM Ltd.
* Author: Catalin Marinas <catalin.marinas@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/syscalls.h>
/*
* Clone a task - this clones the calling program thread.
*/
asmlinkage long sys_clone(unsigned long clone_flags, unsigned long newsp,
int __user *parent_tidptr, unsigned long tls_val,
int __user *child_tidptr, struct pt_regs *regs)
{
if (!newsp)
newsp = regs->sp;
/* 16-byte aligned stack mandatory on AArch64 */
if (newsp & 15)
return -EINVAL;
return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
}
/*
* sys_execve() executes a new program.
*/
asmlinkage long sys_execve(const char __user *filenamei,
const char __user *const __user *argv,
const char __user *const __user *envp,
struct pt_regs *regs)
{
long error;
char * filename;
filename = getname(filenamei);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename, argv, envp, regs);
putname(filename);
out:
return error;
}
int kernel_execve(const char *filename,
const char *const argv[],
const char *const envp[])
{
struct pt_regs regs;
int ret;
memset(&regs, 0, sizeof(struct pt_regs));
ret = do_execve(filename,
(const char __user *const __user *)argv,
(const char __user *const __user *)envp, &regs);
if (ret < 0)
goto out;
/*
* Save argc to the register structure for userspace.
*/
regs.regs[0] = ret;
/*
* We were successful. We won't be returning to our caller, but
* instead to user space by manipulating the kernel stack.
*/
asm( "add x0, %0, %1\n\t"
"mov x1, %2\n\t"
"mov x2, %3\n\t"
"bl memmove\n\t" /* copy regs to top of stack */
"mov x27, #0\n\t" /* not a syscall */
"mov x28, %0\n\t" /* thread structure */
"mov sp, x0\n\t" /* reposition stack pointer */
"b ret_to_user"
:
: "r" (current_thread_info()),
"Ir" (THREAD_START_SP - sizeof(regs)),
"r" (&regs),
"Ir" (sizeof(regs))
: "x0", "x1", "x2", "x27", "x28", "x30", "memory");
out:
return ret;
}
EXPORT_SYMBOL(kernel_execve);
asmlinkage long sys_mmap(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
unsigned long fd, off_t off)
{
if (offset_in_page(off) != 0)
return -EINVAL;
return sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
}
/*
* Wrappers to pass the pt_regs argument.
*/
#define sys_execve sys_execve_wrapper
#define sys_clone sys_clone_wrapper
#define sys_rt_sigreturn sys_rt_sigreturn_wrapper
#define sys_sigaltstack sys_sigaltstack_wrapper
#include <asm/syscalls.h>
#undef __SYSCALL
#define __SYSCALL(nr, sym) [nr] = sym,
/*
* The sys_call_table array must be 4K aligned to be accessible from
* kernel/entry.S.
*/
void *sys_call_table[__NR_syscalls] __aligned(4096) = {
[0 ... __NR_syscalls - 1] = sys_ni_syscall,
#include <asm/unistd.h>
};
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