linux/arch/arm26/kernel/sys_arm.c
Hugh Dickins cdfb82fff3 [PATCH] freepgt: arm26 FIRST_USER_ADDRESS PAGE_SIZE
ARM26 define FIRST_USER_ADDRESS as PAGE_SIZE (beyond the machine vectors when
they are mapped low), and use that definition in place of locally defined
MIN_MAP_ADDR.  Previously, ARM26 permitted user mappings at 0 if the machine
vectors were mapped high; but that's inconsistent with ARM, and
FIRST_USER_ADDRESS would then have to be determined at runtime.  Let's fix it
at PAGE_SIZE throughout the architecture.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-19 13:29:22 -07:00

323 lines
7.9 KiB
C

/*
* linux/arch/arm26/kernel/sys_arm.c
*
* Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c
* Copyright (C) 1995, 1996 Russell King.
* Copyright (C) 2003 Ian Molton.
*
* 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 file contains various random system calls that
* have a non-standard calling sequence on the Linux/arm
* platform.
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/stat.h>
#include <linux/syscalls.h>
#include <linux/mman.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/utsname.h>
#include <asm/uaccess.h>
#include <asm/ipc.h>
extern unsigned long do_mremap(unsigned long addr, unsigned long old_len,
unsigned long new_len, unsigned long flags,
unsigned long new_addr);
/*
* sys_pipe() is the normal C calling standard for creating
* a pipe. It's not the way unix traditionally does this, though.
*/
asmlinkage int sys_pipe(unsigned long * fildes)
{
int fd[2];
int error;
error = do_pipe(fd);
if (!error) {
if (copy_to_user(fildes, fd, 2*sizeof(int)))
error = -EFAULT;
}
return error;
}
/* common code for old and new mmaps */
inline long do_mmap2(
unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long pgoff)
{
int error = -EINVAL;
struct file * file = NULL;
flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
/*
* If we are doing a fixed mapping, and address < FIRST_USER_ADDRESS,
* then deny it.
*/
if (flags & MAP_FIXED && addr < FIRST_USER_ADDRESS)
goto out;
error = -EBADF;
if (!(flags & MAP_ANONYMOUS)) {
file = fget(fd);
if (!file)
goto out;
}
down_write(&current->mm->mmap_sem);
error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
up_write(&current->mm->mmap_sem);
if (file)
fput(file);
out:
return error;
}
struct mmap_arg_struct {
unsigned long addr;
unsigned long len;
unsigned long prot;
unsigned long flags;
unsigned long fd;
unsigned long offset;
};
asmlinkage int old_mmap(struct mmap_arg_struct *arg)
{
int error = -EFAULT;
struct mmap_arg_struct a;
if (copy_from_user(&a, arg, sizeof(a)))
goto out;
error = -EINVAL;
if (a.offset & ~PAGE_MASK)
goto out;
error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
out:
return error;
}
asmlinkage unsigned long
sys_arm_mremap(unsigned long addr, unsigned long old_len,
unsigned long new_len, unsigned long flags,
unsigned long new_addr)
{
unsigned long ret = -EINVAL;
/*
* If we are doing a fixed mapping, and address < FIRST_USER_ADDRESS,
* then deny it.
*/
if (flags & MREMAP_FIXED && new_addr < FIRST_USER_ADDRESS)
goto out;
down_write(&current->mm->mmap_sem);
ret = do_mremap(addr, old_len, new_len, flags, new_addr);
up_write(&current->mm->mmap_sem);
out:
return ret;
}
/*
* Perform the select(nd, in, out, ex, tv) and mmap() system
* calls.
*/
struct sel_arg_struct {
unsigned long n;
fd_set *inp, *outp, *exp;
struct timeval *tvp;
};
asmlinkage int old_select(struct sel_arg_struct *arg)
{
struct sel_arg_struct a;
if (copy_from_user(&a, arg, sizeof(a)))
return -EFAULT;
/* sys_select() does the appropriate kernel locking */
return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
}
/*
* sys_ipc() is the de-multiplexer for the SysV IPC calls..
*
* This is really horribly ugly.
*/
asmlinkage int sys_ipc (uint call, int first, int second, int third, void *ptr, long fifth)
{
int version, ret;
version = call >> 16; /* hack for backward compatibility */
call &= 0xffff;
switch (call) {
case SEMOP:
return sys_semop (first, (struct sembuf *)ptr, second);
case SEMGET:
return sys_semget (first, second, third);
case SEMCTL: {
union semun fourth;
if (!ptr)
return -EINVAL;
if (get_user(fourth.__pad, (void **) ptr))
return -EFAULT;
return sys_semctl (first, second, third, fourth);
}
case MSGSND:
return sys_msgsnd (first, (struct msgbuf *) ptr,
second, third);
case MSGRCV:
switch (version) {
case 0: {
struct ipc_kludge tmp;
if (!ptr)
return -EINVAL;
if (copy_from_user(&tmp,(struct ipc_kludge *) ptr,
sizeof (tmp)))
return -EFAULT;
return sys_msgrcv (first, tmp.msgp, second,
tmp.msgtyp, third);
}
default:
return sys_msgrcv (first,
(struct msgbuf *) ptr,
second, fifth, third);
}
case MSGGET:
return sys_msgget ((key_t) first, second);
case MSGCTL:
return sys_msgctl (first, second, (struct msqid_ds *) ptr);
case SHMAT:
switch (version) {
default: {
ulong raddr;
ret = do_shmat (first, (char *) ptr, second, &raddr);
if (ret)
return ret;
return put_user (raddr, (ulong *) third);
}
case 1: /* iBCS2 emulator entry point */
if (!segment_eq(get_fs(), get_ds()))
return -EINVAL;
return do_shmat (first, (char *) ptr,
second, (ulong *) third);
}
case SHMDT:
return sys_shmdt ((char *)ptr);
case SHMGET:
return sys_shmget (first, second, third);
case SHMCTL:
return sys_shmctl (first, second,
(struct shmid_ds *) ptr);
default:
return -EINVAL;
}
}
/* Fork a new task - this creates a new program thread.
* This is called indirectly via a small wrapper
*/
asmlinkage int sys_fork(struct pt_regs *regs)
{
return do_fork(SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
}
/* Clone a task - this clones the calling program thread.
* This is called indirectly via a small wrapper
*/
asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp, struct pt_regs *regs)
{
/*
* We don't support SETTID / CLEARTID (FIXME!!! (nicked from arm32))
*/
if (clone_flags & (CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID))
return -EINVAL;
if (!newsp)
newsp = regs->ARM_sp;
return do_fork(clone_flags, newsp, regs, 0, NULL, NULL);
}
asmlinkage int sys_vfork(struct pt_regs *regs)
{
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
}
/* sys_execve() executes a new program.
* This is called indirectly via a small wrapper
*/
asmlinkage int sys_execve(char *filenamei, char **argv, char **envp, struct pt_regs *regs)
{
int 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;
}
/* FIXME - see if this is correct for arm26 */
long execve(const char *filename, char **argv, char **envp)
{
struct pt_regs regs;
int ret;
memset(&regs, 0, sizeof(struct pt_regs));
ret = do_execve((char *)filename, (char __user * __user *)argv, (char __user * __user *)envp, &regs);
if (ret < 0)
goto out;
/*
* Save argc to the register structure for userspace.
*/
regs.ARM_r0 = ret;
/*
* We were successful. We won't be returning to our caller, but
* instead to user space by manipulating the kernel stack.
*/
asm( "add r0, %0, %1\n\t"
"mov r1, %2\n\t"
"mov r2, %3\n\t"
"bl memmove\n\t" /* copy regs to top of stack */
"mov r8, #0\n\t" /* not a syscall */
"mov r9, %0\n\t" /* thread structure */
"mov sp, r0\n\t" /* reposition stack pointer */
"b ret_to_user"
:
: "r" (current_thread_info()),
"Ir" (THREAD_SIZE - 8 - sizeof(regs)),
"r" (&regs),
"Ir" (sizeof(regs))
: "r0", "r1", "r2", "r3", "ip", "memory");
out:
return ret;
}
EXPORT_SYMBOL(execve);