arch/xtensa/kernel/syscalls.c - maze/linux - Git at Google

 /*
  * arch/xtensa/kernel/syscall.c
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
  * Copyright (C) 2001 - 2005 Tensilica Inc.
  * Copyright (C) 2000 Silicon Graphics, Inc.
  * Copyright (C) 1995 - 2000 by Ralf Baechle
  *
  * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
  * Marc Gauthier <marc@tensilica.com, marc@alumni.uwaterloo.ca>
  * Chris Zankel <chris@zankel.net>
  * Kevin Chea
  *
  */

 #define DEBUG	0

 #include <linux/config.h>
 #include <linux/linkage.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
 #include <linux/smp_lock.h>
 #include <linux/mman.h>
 #include <linux/sched.h>
 #include <linux/file.h>
 #include <linux/slab.h>
 #include <linux/utsname.h>
 #include <linux/unistd.h>
 #include <linux/stringify.h>
 #include <linux/syscalls.h>
 #include <linux/sem.h>
 #include <linux/msg.h>
 #include <linux/shm.h>
 #include <linux/errno.h>
 #include <asm/ptrace.h>
 #include <asm/signal.h>
 #include <asm/uaccess.h>
 #include <asm/hardirq.h>
 #include <asm/mman.h>
 #include <asm/shmparam.h>
 #include <asm/page.h>
 #include <asm/ipc.h>

 extern void do_syscall_trace(void);
 typedef int (*syscall_t)(void *a0,...);
 extern int (*do_syscalls)(struct pt_regs *regs, syscall_t fun,
 				     int narg);
 extern syscall_t sys_call_table[];
 extern unsigned char sys_narg_table[];

 /*
  * sys_pipe() is the normal C calling standard for creating a pipe. It's not
  * the way unix traditional does this, though.
  */

 int sys_pipe(int __user *userfds)
 {
 	int fd[2];
 	int error;

 	error = do_pipe(fd);
 	if (!error) {
 		if (copy_to_user(userfds, fd, 2 * sizeof(int)))
 			error = -EFAULT;
 	}
 	return error;
 }

 /*
  * Common code for old and new mmaps.
  */

 static inline long do_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;

 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 	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;
 }

 unsigned long old_mmap(unsigned long addr, size_t len, int prot,
 		       int flags, int fd, off_t offset)
 {
 	return do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 }

 long sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 	       unsigned long flags, unsigned long fd, unsigned long pgoff)
 {
 	return do_mmap2(addr, len, prot, flags, fd, pgoff);
 }

 int sys_fork(struct pt_regs *regs)
 {
 	return do_fork(SIGCHLD, regs->areg[1], regs, 0, NULL, NULL);
 }

 int sys_vfork(struct pt_regs *regs)
 {
 	return do_fork(CLONE_VFORK|CLONE_VM|SIGCHLD, regs->areg[1],
 		       regs, 0, NULL, NULL);
 }

 int sys_clone(struct pt_regs *regs)
 {
 	unsigned long clone_flags;
 	unsigned long newsp;
 	int __user *parent_tidptr, *child_tidptr;
 	clone_flags = regs->areg[4];
 	newsp = regs->areg[3];
 	parent_tidptr = (int __user *)regs->areg[5];
 	child_tidptr = (int __user *)regs->areg[6];
 	if (!newsp)
 		newsp = regs->areg[1];
 	return do_fork(clone_flags,newsp,regs,0,parent_tidptr,child_tidptr);
 }

 /*
  * sys_execve() executes a new program.
  */

 int sys_execve(struct pt_regs *regs)
 {
 	int error;
 	char * filename;

 	filename = getname((char *) (long)regs->areg[5]);
 	error = PTR_ERR(filename);
 	if (IS_ERR(filename))
 		goto out;
 	error = do_execve(filename, (char **) (long)regs->areg[3],
 	                  (char **) (long)regs->areg[4], regs);
 	putname(filename);

 out:
 	return error;
 }

 int sys_uname(struct old_utsname * name)
 {
 	if (name && !copy_to_user(name, &system_utsname, sizeof (*name)))
 		return 0;
 	return -EFAULT;
 }

 int sys_olduname(struct oldold_utsname * name)
 {
 	int error;

 	if (!name)
 		return -EFAULT;
 	if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 		return -EFAULT;

 	error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
 	error -= __put_user(0,name->sysname+__OLD_UTS_LEN);
 	error -= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
 	error -= __put_user(0,name->nodename+__OLD_UTS_LEN);
 	error -= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
 	error -= __put_user(0,name->release+__OLD_UTS_LEN);
 	error -= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
 	error -= __put_user(0,name->version+__OLD_UTS_LEN);
 	error -= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
 	error -= __put_user(0,name->machine+__OLD_UTS_LEN);

 	return error ? -EFAULT : 0;
 }


 /*
  * Build the string table for the builtin "poor man's strace".
  */

 #if DEBUG
 #define SYSCALL(fun, narg) #fun,
 static char *sfnames[] = {
 #include "syscalls.h"
 };
 #undef SYS
 #endif

 void system_call (struct pt_regs *regs)
 {
 	syscall_t syscall;
 	unsigned long parm0, parm1, parm2, parm3, parm4, parm5;
 	int nargs, res;
 	unsigned int syscallnr;
 	int ps;

 #if DEBUG
 	int i;
 	unsigned long parms[6];
 	char *sysname;
 #endif

 	regs->syscall = regs->areg[2];

 	do_syscall_trace();

 	/* Have to load after syscall_trace because strace
 	 * sometimes changes regs->syscall.
 	 */
 	syscallnr = regs->syscall;

 	parm0 = parm1 = parm2 = parm3 = parm4 = parm5 = 0;

 	/* Restore interrupt level to syscall invoker's.
 	 * If this were in assembly, we wouldn't disable
 	 * interrupts in the first place:
 	 */
 	local_save_flags (ps);
 	local_irq_restore((ps & ~XCHAL_PS_INTLEVEL_MASK) |
 			  (regs->ps & XCHAL_PS_INTLEVEL_MASK) );

 	if (syscallnr > __NR_Linux_syscalls) {
 		regs->areg[2] = -ENOSYS;
 		return;
 	}

 	syscall = sys_call_table[syscallnr];
 	nargs = sys_narg_table[syscallnr];

 	if (syscall == NULL) {
 		regs->areg[2] = -ENOSYS;
 		return;
 	}

 	/* There shouldn't be more than six arguments in the table! */

 	if (nargs > 6)
 		panic("Internal error - too many syscall arguments (%d)!\n",
 		      nargs);

 	/* Linux takes system-call arguments in registers.  The ABI
          * and Xtensa software conventions require the system-call
          * number in a2.  If an argument exists in a2, we move it to
          * the next available register.  Note that for improved
          * efficiency, we do NOT shift all parameters down one
          * register to maintain the original order.
 	 *
          * At best case (zero arguments), we just write the syscall
          * number to a2.  At worst case (1 to 6 arguments), we move
          * the argument in a2 to the next available register, then
          * write the syscall number to a2.
 	 *
          * For clarity, the following truth table enumerates all
          * possibilities.
 	 *
          * arguments	syscall number	arg0, arg1, arg2, arg3, arg4, arg5
          * ---------	--------------	----------------------------------
 	 *	0	      a2
 	 *	1	      a2	a3
 	 *	2	      a2	a4,   a3
 	 *	3	      a2	a5,   a3,   a4
 	 *	4	      a2	a6,   a3,   a4,   a5
 	 *	5	      a2	a7,   a3,   a4,   a5,   a6
 	 *	6	      a2	a8,   a3,   a4,   a5,   a6,   a7
 	 */
 	if (nargs) {
 		parm0 = regs->areg[nargs+2];
 		parm1 = regs->areg[3];
 		parm2 = regs->areg[4];
 		parm3 = regs->areg[5];
 		parm4 = regs->areg[6];
 		parm5 = regs->areg[7];
 	} else /* nargs == 0 */
 		parm0 = (unsigned long) regs;

 #if DEBUG
 	parms[0] = parm0;
 	parms[1] = parm1;
 	parms[2] = parm2;
 	parms[3] = parm3;
 	parms[4] = parm4;
 	parms[5] = parm5;

 	sysname = sfnames[syscallnr];
 	if (strncmp(sysname, "sys_", 4) == 0)
 		sysname = sysname + 4;

 	printk("\017SYSCALL:I:%x:%d:%s  %s(", regs->pc, current->pid,
 	       current->comm, sysname);
 	for (i = 0; i < nargs; i++)
 		printk((i>0) ? ", %#lx" : "%#lx", parms[i]);
 	printk(")\n");
 #endif

 	res = syscall((void *)parm0, parm1, parm2, parm3, parm4, parm5);

 #if DEBUG
 	printk("\017SYSCALL:O:%d:%s  %s(",current->pid, current->comm, sysname);
 	for (i = 0; i < nargs; i++)
 		printk((i>0) ? ", %#lx" : "%#lx", parms[i]);
 	if (res < 4096)
 		printk(") = %d\n", res);
 	else
 		printk(") = %#x\n", res);
 #endif /* DEBUG */

 	regs->areg[2] = res;
 	do_syscall_trace();
 }

 /*
  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
  *
  * This is really horribly ugly.
  */

 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;
 	ret = -ENOSYS;

 	switch (call) {
 	case SEMOP:
 		ret = sys_semtimedop (first, (struct sembuf __user *)ptr,
 				     second, NULL);
 		break;

 	case SEMTIMEDOP:
 		ret = sys_semtimedop (first, (struct sembuf __user *)ptr,
 				      second, (const struct timespec *) fifth);
 		break;

 	case SEMGET:
 		ret = sys_semget (first, second, third);
 		break;

 	case SEMCTL: {
 		union semun fourth;

 		if (ptr && !get_user(fourth.__pad, (void *__user *) ptr))
 			ret = sys_semctl (first, second, third, fourth);
 		break;
 		}

 	case MSGSND:
 		ret = sys_msgsnd (first, (struct msgbuf __user*) ptr,
 				  second, third);
 		break;

 	case MSGRCV:
 		switch (version) {
 		case 0: {
 			struct ipc_kludge tmp;

 			if (ptr && !copy_from_user(&tmp,
 					   (struct ipc_kludge *) ptr,
 					   sizeof (tmp)))
 				ret = sys_msgrcv (first, tmp.msgp, second,
 						  tmp.msgtyp, third);
 			break;
 			}

 		default:
 			ret = sys_msgrcv (first, (struct msgbuf __user *) ptr,
 					  second, 0, third);
 			break;
 		}
 		break;

 	case MSGGET:
 		ret = sys_msgget ((key_t) first, second);
 		break;

 	case MSGCTL:
 		ret = sys_msgctl (first, second, (struct msqid_ds __user*) ptr);
 		break;

 	case SHMAT: {
 		ulong raddr;
 		ret = do_shmat (first, (char __user *) ptr, second, &raddr);

 		if (!ret)
 			ret = put_user (raddr, (ulong __user *) third);

 		break;
 		}

 	case SHMDT:
 		ret = sys_shmdt ((char __user *)ptr);
 		break;

 	case SHMGET:
 		ret = sys_shmget (first, second, third);
 		break;

 	case SHMCTL:
 		ret = sys_shmctl (first, second, (struct shmid_ds __user*) ptr);
 		break;
 	}
 	return ret;
 }
	/*
	* arch/xtensa/kernel/syscall.c
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*
	* Copyright (C) 2001 - 2005 Tensilica Inc.
	* Copyright (C) 2000 Silicon Graphics, Inc.
	* Copyright (C) 1995 - 2000 by Ralf Baechle
	*
	* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
	* Marc Gauthier <marc@tensilica.com, marc@alumni.uwaterloo.ca>
	* Chris Zankel <chris@zankel.net>
	* Kevin Chea
	*
	*/

	#define DEBUG 0

	#include <linux/config.h>
	#include <linux/linkage.h>
	#include <linux/mm.h>
	#include <linux/smp.h>
	#include <linux/smp_lock.h>
	#include <linux/mman.h>
	#include <linux/sched.h>
	#include <linux/file.h>
	#include <linux/slab.h>
	#include <linux/utsname.h>
	#include <linux/unistd.h>
	#include <linux/stringify.h>
	#include <linux/syscalls.h>
	#include <linux/sem.h>
	#include <linux/msg.h>
	#include <linux/shm.h>
	#include <linux/errno.h>
	#include <asm/ptrace.h>
	#include <asm/signal.h>
	#include <asm/uaccess.h>
	#include <asm/hardirq.h>
	#include <asm/mman.h>
	#include <asm/shmparam.h>
	#include <asm/page.h>
	#include <asm/ipc.h>

	extern void do_syscall_trace(void);
	typedef int (syscall_t)(void a0,...);
	extern int (do_syscalls)(struct pt_regs regs, syscall_t fun,
	int narg);
	extern syscall_t sys_call_table[];
	extern unsigned char sys_narg_table[];

	/*
	* sys_pipe() is the normal C calling standard for creating a pipe. It's not
	* the way unix traditional does this, though.
	*/

	int sys_pipe(int __user *userfds)
	{
	int fd[2];
	int error;

	error = do_pipe(fd);
	if (!error) {
	if (copy_to_user(userfds, fd, 2 * sizeof(int)))
	error = -EFAULT;
	}
	return error;
	}

	/*
	* Common code for old and new mmaps.
	*/

	static inline long do_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;

	flags &= ~(MAP_EXECUTABLE \| MAP_DENYWRITE);
	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;
	}

	unsigned long old_mmap(unsigned long addr, size_t len, int prot,
	int flags, int fd, off_t offset)
	{
	return do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
	}

	long sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
	unsigned long flags, unsigned long fd, unsigned long pgoff)
	{
	return do_mmap2(addr, len, prot, flags, fd, pgoff);
	}

	int sys_fork(struct pt_regs *regs)
	{
	return do_fork(SIGCHLD, regs->areg[1], regs, 0, NULL, NULL);
	}

	int sys_vfork(struct pt_regs *regs)
	{
	return do_fork(CLONE_VFORK\|CLONE_VM\|SIGCHLD, regs->areg[1],
	regs, 0, NULL, NULL);
	}

	int sys_clone(struct pt_regs *regs)
	{
	unsigned long clone_flags;
	unsigned long newsp;
	int __user parent_tidptr, child_tidptr;
	clone_flags = regs->areg[4];
	newsp = regs->areg[3];
	parent_tidptr = (int __user *)regs->areg[5];
	child_tidptr = (int __user *)regs->areg[6];
	if (!newsp)
	newsp = regs->areg[1];
	return do_fork(clone_flags,newsp,regs,0,parent_tidptr,child_tidptr);
	}

	/*
	* sys_execve() executes a new program.
	*/

	int sys_execve(struct pt_regs *regs)
	{
	int error;
	char * filename;

	filename = getname((char *) (long)regs->areg[5]);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
	goto out;
	error = do_execve(filename, (char **) (long)regs->areg[3],
	(char **) (long)regs->areg[4], regs);
	putname(filename);

	out:
	return error;
	}

	int sys_uname(struct old_utsname * name)
	{
	if (name && !copy_to_user(name, &system_utsname, sizeof (*name)))
	return 0;
	return -EFAULT;
	}

	int sys_olduname(struct oldold_utsname * name)
	{
	int error;

	if (!name)
	return -EFAULT;
	if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
	return -EFAULT;

	error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
	error -= __put_user(0,name->sysname+__OLD_UTS_LEN);
	error -= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
	error -= __put_user(0,name->nodename+__OLD_UTS_LEN);
	error -= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
	error -= __put_user(0,name->release+__OLD_UTS_LEN);
	error -= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
	error -= __put_user(0,name->version+__OLD_UTS_LEN);
	error -= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
	error -= __put_user(0,name->machine+__OLD_UTS_LEN);

	return error ? -EFAULT : 0;
	}


	/*
	* Build the string table for the builtin "poor man's strace".
	*/

	#if DEBUG
	#define SYSCALL(fun, narg) #fun,
	static char *sfnames[] = {
	#include "syscalls.h"
	};
	#undef SYS
	#endif

	void system_call (struct pt_regs *regs)
	{
	syscall_t syscall;
	unsigned long parm0, parm1, parm2, parm3, parm4, parm5;
	int nargs, res;
	unsigned int syscallnr;
	int ps;

	#if DEBUG
	int i;
	unsigned long parms[6];
	char *sysname;
	#endif

	regs->syscall = regs->areg[2];

	do_syscall_trace();

	/* Have to load after syscall_trace because strace
	* sometimes changes regs->syscall.
	*/
	syscallnr = regs->syscall;

	parm0 = parm1 = parm2 = parm3 = parm4 = parm5 = 0;

	/* Restore interrupt level to syscall invoker's.
	* If this were in assembly, we wouldn't disable
	* interrupts in the first place:
	*/
	local_save_flags (ps);
	local_irq_restore((ps & ~XCHAL_PS_INTLEVEL_MASK) \|
	(regs->ps & XCHAL_PS_INTLEVEL_MASK) );

	if (syscallnr > __NR_Linux_syscalls) {
	regs->areg[2] = -ENOSYS;
	return;
	}

	syscall = sys_call_table[syscallnr];
	nargs = sys_narg_table[syscallnr];

	if (syscall == NULL) {
	regs->areg[2] = -ENOSYS;
	return;
	}

	/* There shouldn't be more than six arguments in the table! */

	if (nargs > 6)
	panic("Internal error - too many syscall arguments (%d)!\n",
	nargs);

	/* Linux takes system-call arguments in registers. The ABI
	* and Xtensa software conventions require the system-call
	* number in a2. If an argument exists in a2, we move it to
	* the next available register. Note that for improved
	* efficiency, we do NOT shift all parameters down one
	* register to maintain the original order.
	*
	* At best case (zero arguments), we just write the syscall
	* number to a2. At worst case (1 to 6 arguments), we move
	* the argument in a2 to the next available register, then
	* write the syscall number to a2.
	*
	* For clarity, the following truth table enumerates all
	* possibilities.
	*
	* arguments syscall number arg0, arg1, arg2, arg3, arg4, arg5
	* --------- -------------- ----------------------------------
	* 0 a2
	* 1 a2 a3
	* 2 a2 a4, a3
	* 3 a2 a5, a3, a4
	* 4 a2 a6, a3, a4, a5
	* 5 a2 a7, a3, a4, a5, a6
	* 6 a2 a8, a3, a4, a5, a6, a7
	*/
	if (nargs) {
	parm0 = regs->areg[nargs+2];
	parm1 = regs->areg[3];
	parm2 = regs->areg[4];
	parm3 = regs->areg[5];
	parm4 = regs->areg[6];
	parm5 = regs->areg[7];
	} else /* nargs == 0 */
	parm0 = (unsigned long) regs;

	#if DEBUG
	parms[0] = parm0;
	parms[1] = parm1;
	parms[2] = parm2;
	parms[3] = parm3;
	parms[4] = parm4;
	parms[5] = parm5;

	sysname = sfnames[syscallnr];
	if (strncmp(sysname, "sys_", 4) == 0)
	sysname = sysname + 4;

	printk("\017SYSCALL:I:%x:%d:%s %s(", regs->pc, current->pid,
	current->comm, sysname);
	for (i = 0; i < nargs; i++)
	printk((i>0) ? ", %#lx" : "%#lx", parms[i]);
	printk(")\n");
	#endif

	res = syscall((void *)parm0, parm1, parm2, parm3, parm4, parm5);

	#if DEBUG
	printk("\017SYSCALL:O:%d:%s %s(",current->pid, current->comm, sysname);
	for (i = 0; i < nargs; i++)
	printk((i>0) ? ", %#lx" : "%#lx", parms[i]);
	if (res < 4096)
	printk(") = %d\n", res);
	else
	printk(") = %#x\n", res);
	#endif /* DEBUG */

	regs->areg[2] = res;
	do_syscall_trace();
	}

	/*
	* sys_ipc() is the de-multiplexer for the SysV IPC calls..
	*
	* This is really horribly ugly.
	*/

	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;
	ret = -ENOSYS;

	switch (call) {
	case SEMOP:
	ret = sys_semtimedop (first, (struct sembuf __user *)ptr,
	second, NULL);
	break;

	case SEMTIMEDOP:
	ret = sys_semtimedop (first, (struct sembuf __user *)ptr,
	second, (const struct timespec *) fifth);
	break;

	case SEMGET:
	ret = sys_semget (first, second, third);
	break;

	case SEMCTL: {
	union semun fourth;

	if (ptr && !get_user(fourth.__pad, (void __user ) ptr))
	ret = sys_semctl (first, second, third, fourth);
	break;
	}

	case MSGSND:
	ret = sys_msgsnd (first, (struct msgbuf __user*) ptr,
	second, third);
	break;

	case MSGRCV:
	switch (version) {
	case 0: {
	struct ipc_kludge tmp;

	if (ptr && !copy_from_user(&tmp,
	(struct ipc_kludge *) ptr,
	sizeof (tmp)))
	ret = sys_msgrcv (first, tmp.msgp, second,
	tmp.msgtyp, third);
	break;
	}

	default:
	ret = sys_msgrcv (first, (struct msgbuf __user *) ptr,
	second, 0, third);
	break;
	}
	break;

	case MSGGET:
	ret = sys_msgget ((key_t) first, second);
	break;

	case MSGCTL:
	ret = sys_msgctl (first, second, (struct msqid_ds __user*) ptr);
	break;

	case SHMAT: {
	ulong raddr;
	ret = do_shmat (first, (char __user *) ptr, second, &raddr);

	if (!ret)
	ret = put_user (raddr, (ulong __user *) third);

	break;
	}

	case SHMDT:
	ret = sys_shmdt ((char __user *)ptr);
	break;

	case SHMGET:
	ret = sys_shmget (first, second, third);
	break;

	case SHMCTL:
	ret = sys_shmctl (first, second, (struct shmid_ds __user*) ptr);
	break;
	}
	return ret;
	}