linux/arch/x86/kernel/sys_i386_32.c
Al Viro f8b7256096 Unify sys_mmap*
New helper - sys_mmap_pgoff(); switch syscalls to using it.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-11 06:44:29 -05:00

224 lines
5.3 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 <linux/uaccess.h>
#include <linux/unistd.h>
#include <asm/syscalls.h>
/*
* 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_mmap_pgoff(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;
}