diff options
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/sys.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/arm64/kernel/sys.c b/arch/arm64/kernel/sys.c new file mode 100644 index 000000000000..905fcfb0ddd0 --- /dev/null +++ b/arch/arm64/kernel/sys.c @@ -0,0 +1,138 @@ +/* + * 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(®s, 0, sizeof(struct pt_regs)); + ret = do_execve(filename, + (const char __user *const __user *)argv, + (const char __user *const __user *)envp, ®s); + 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" (®s), + "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> +}; |