linux/arch/x86/kernel/sys_i386_32.c
Ulrich Drepper d35c7b0e54 unified (weak) sys_pipe implementation
This replaces the duplicated arch-specific versions of "sys_pipe()" with
one unified implementation.  This removes almost 250 lines of duplicated
code.

It's marked __weak, so that *if* an architecture wants to override the
default implementation it can do so by simply having its own replacement
version, since many architectures use alternate calling conventions for
the 'pipe()' system call for legacy reasons (ie traditional UNIX
implementations often return the two file descriptors in registers)

I still haven't changed the cris version even though Linus says the BKL
isn't needed.  The arch maintainer can easily do it if there are really
no obstacles.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-03 13:50:33 -07:00

247 lines
5.8 KiB
C

/*
* This file contains various random system calls that
* have a non-standard calling sequence on the Linux/i386
* platform.
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/smp.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/file.h>
#include <linux/utsname.h>
#include <linux/ipc.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long pgoff)
{
int error = -EBADF;
struct file *file = NULL;
struct mm_struct *mm = current->mm;
flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
if (!(flags & MAP_ANONYMOUS)) {
file = fget(fd);
if (!file)
goto out;
}
down_write(&mm->mmap_sem);
error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
up_write(&mm->mmap_sem);
if (file)
fput(file);
out:
return error;
}
/*
* Perform the select(nd, in, out, ex, tv) and mmap() system
* calls. Linux/i386 didn't use to be able to handle more than
* 4 system call parameters, so these system calls used a memory
* block for parameter passing..
*/
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 __user *arg)
{
struct mmap_arg_struct a;
int err = -EFAULT;
if (copy_from_user(&a, arg, sizeof(a)))
goto out;
err = -EINVAL;
if (a.offset & ~PAGE_MASK)
goto out;
err = sys_mmap2(a.addr, a.len, a.prot, a.flags,
a.fd, a.offset >> PAGE_SHIFT);
out:
return err;
}
struct sel_arg_struct {
unsigned long n;
fd_set __user *inp, *outp, *exp;
struct timeval __user *tvp;
};
asmlinkage int old_select(struct sel_arg_struct __user *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 __user *ptr, long fifth)
{
int version, ret;
version = call >> 16; /* hack for backward compatibility */
call &= 0xffff;
switch (call) {
case SEMOP:
return sys_semtimedop (first, (struct sembuf __user *)ptr, second, NULL);
case SEMTIMEDOP:
return sys_semtimedop(first, (struct sembuf __user *)ptr, second,
(const struct timespec __user *)fifth);
case SEMGET:
return sys_semget (first, second, third);
case SEMCTL: {
union semun fourth;
if (!ptr)
return -EINVAL;
if (get_user(fourth.__pad, (void __user * __user *) ptr))
return -EFAULT;
return sys_semctl (first, second, third, fourth);
}
case MSGSND:
return sys_msgsnd (first, (struct msgbuf __user *) 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 __user *) ptr,
sizeof (tmp)))
return -EFAULT;
return sys_msgrcv (first, tmp.msgp, second,
tmp.msgtyp, third);
}
default:
return sys_msgrcv (first,
(struct msgbuf __user *) ptr,
second, fifth, third);
}
case MSGGET:
return sys_msgget ((key_t) first, second);
case MSGCTL:
return sys_msgctl (first, second, (struct msqid_ds __user *) ptr);
case SHMAT:
switch (version) {
default: {
ulong raddr;
ret = do_shmat (first, (char __user *) ptr, second, &raddr);
if (ret)
return ret;
return put_user (raddr, (ulong __user *) third);
}
case 1: /* iBCS2 emulator entry point */
if (!segment_eq(get_fs(), get_ds()))
return -EINVAL;
/* The "(ulong *) third" is valid _only_ because of the kernel segment thing */
return do_shmat (first, (char __user *) ptr, second, (ulong *) third);
}
case SHMDT:
return sys_shmdt ((char __user *)ptr);
case SHMGET:
return sys_shmget (first, second, third);
case SHMCTL:
return sys_shmctl (first, second,
(struct shmid_ds __user *) ptr);
default:
return -ENOSYS;
}
}
/*
* Old cruft
*/
asmlinkage int sys_uname(struct old_utsname __user * name)
{
int err;
if (!name)
return -EFAULT;
down_read(&uts_sem);
err = copy_to_user(name, utsname(), sizeof (*name));
up_read(&uts_sem);
return err?-EFAULT:0;
}
asmlinkage int sys_olduname(struct oldold_utsname __user * name)
{
int error;
if (!name)
return -EFAULT;
if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
return -EFAULT;
down_read(&uts_sem);
error = __copy_to_user(&name->sysname, &utsname()->sysname,
__OLD_UTS_LEN);
error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
error |= __copy_to_user(&name->nodename, &utsname()->nodename,
__OLD_UTS_LEN);
error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
error |= __copy_to_user(&name->release, &utsname()->release,
__OLD_UTS_LEN);
error |= __put_user(0, name->release + __OLD_UTS_LEN);
error |= __copy_to_user(&name->version, &utsname()->version,
__OLD_UTS_LEN);
error |= __put_user(0, name->version + __OLD_UTS_LEN);
error |= __copy_to_user(&name->machine, &utsname()->machine,
__OLD_UTS_LEN);
error |= __put_user(0, name->machine + __OLD_UTS_LEN);
up_read(&uts_sem);
error = error ? -EFAULT : 0;
return error;
}
/*
* Do a system call from kernel instead of calling sys_execve so we
* end up with proper pt_regs.
*/
int kernel_execve(const char *filename, char *const argv[], char *const envp[])
{
long __res;
asm volatile ("push %%ebx ; movl %2,%%ebx ; int $0x80 ; pop %%ebx"
: "=a" (__res)
: "0" (__NR_execve),"ri" (filename),"c" (argv), "d" (envp) : "memory");
return __res;
}