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=============================================================================

	MOXA Smartio Family Device Driver Ver 1.1 Installation Guide
		    for Linux Kernel 2.2.x and 2.0.3x
	       Copyright (C) 1999, Moxa Technologies Co, Ltd.
=============================================================================
Content

1. Introduction
2. System Requirement
3. Installation
4. Utilities
5. Setserial
6. Troubleshooting

-----------------------------------------------------------------------------
1. Introduction

   The Smartio family Linux driver, Ver. 1.1, supports following multiport
   boards.

    -C104P/H/HS, C104H/PCI, C104HS/PCI, CI-104J 4 port multiport board.
    -C168P/H/HS, C168H/PCI 8 port multiport board.

   This driver has been modified a little and cleaned up from the Moxa
   contributed driver code and merged into Linux 2.2.14pre. In particular
   official major/minor numbers have been assigned which are different to
   those the original Moxa supplied driver used.

   This driver and installation procedure have been developed upon Linux Kernel
   2.2.5 and backward compatible to 2.0.3x. This driver supports Intel x86 and
   Alpha hardware platform. In order to maintain compatibility, this version
   has also been properly tested with RedHat, OpenLinux, TurboLinux and
   S.u.S.E Linux. However, if compatibility problem occurs, please contact
   Moxa at support@moxa.com.tw.

   In addition to device driver, useful utilities are also provided in this
   version. They are
    - msdiag     Diagnostic program for detecting installed Moxa Smartio boards.
    - msmon      Monitor program to observe data count and line status signals.
    - msterm     A simple terminal program which is useful in testing serial
	         ports.
    - io-irq.exe Configuration program to setup ISA boards. Please note that
                 this program can only be executed under DOS.

   All the drivers and utilities are published in form of source code under
   GNU General Public License in this version. Please refer to GNU General
   Public License announcement in each source code file for more detail.

   In Moxa's ftp sites, you may always find latest driver at
   ftp://ftp.moxa.com  or ftp://ftp.moxa.com.tw.

   This version of driver can be installed as Loadable Module (Module driver)
   or built-in into kernel (Static driver). You may refer to following
   installation procedure for suitable one. Before you install the driver,
   please refer to hardware installation procedure in the User's Manual.

   We assume the user should be familiar with following documents.
   - Serial-HOWTO
   - Kernel-HOWTO

-----------------------------------------------------------------------------
2. System Requirement
   - Hardware platform: Intel x86 or Alpha machine
   - Kernel version: 2.0.3x or 2.2.x
   - gcc version 2.72 or later
   - Maximum 4 boards can be installed in combination

-----------------------------------------------------------------------------
3. Installation

   3.1 Hardware installation

       There are two types of buses, ISA and PCI, for Smartio family multiport
       board.

       ISA board
       ---------
       You'll have to configure CAP address, I/O address, Interrupt Vector
       as well as IRQ before installing this driver. Please refer to hardware
       installation procedure in User's Manual before proceed any further.
       Please make sure the JP1 is open after the ISA board is set properly.

       PCI board
       ---------
       You may need to adjust IRQ usage in BIOS to avoid from IRQ conflict
       with other ISA devices. Please refer to hardware installation
       procedure in User's Manual in advance.

       IRQ Sharing
       -----------
       Each port within the same multiport board shares the same IRQ. Up to
       4 Moxa Smartio Family multiport boards can be installed together on
       one system and they can share the same IRQ.

   3.2 Driver files and device naming convention

       The driver file may be obtained from ftp, CD-ROM or floppy disk. The
       first step, anyway, is to copy driver file "mxser.tgz" into specified
       directory. e.g. /moxa. The execute commands as below.

       # cd /moxa
       # tar xvf /dev/fd0 
       or
       # cd /moxa
       # cp /mnt/cdrom/<driver directory>/mxser.tgz .
       # tar xvfz mxser.tgz

       You may find all the driver and utilities files in /moxa/mxser.
       Following installation procedure depends on the model you'd like to
       run the driver. If you prefer module driver, please refer to 3.3.
       If static driver is required, please refer to 3.4.

       Dialin and callout port
       -----------------------
       This driver remains traditional serial device properties. There're
       two special file name for each serial port. One is dial-in port
       which is named "ttyMxx". For callout port, the naming convention
       is "cumxx".

       Device naming when more than 2 boards installed
       -----------------------------------------------
       Naming convention for each Smartio multiport board is pre-defined
       as below.

       Board Num.	 Dial-in Port	      Callout port
       1st board	ttyM0  - ttyM7	      cum0  - cum7
       2nd board	ttyM8  - ttyM15       cum8  - cum15
       3rd board	ttyM16 - ttyM23       cum16 - cum23
       4th board	ttyM24 - ttym31       cum24 - cum31

       Board sequence
       --------------
       This driver will activate ISA boards according to the parameter set
       in the driver. After all specified ISA board activated, PCI board
       will be installed in the system automatically driven.
       Therefore the board number is sorted by the CAP address of ISA boards.
       For PCI boards, their sequence will be after ISA boards and C168H/PCI
       has higher priority than C104H/PCI boards.

   3.3 Module driver configuration
       Module driver is easiest way to install. If you prefer static driver
       installation, please skip this paragraph.
       1. Find "Makefile" in /moxa/mxser, then run

	  # make install

	  The driver files "mxser.o" and utilities will be properly compiled
	  and copied to system directories respectively.Then run

	  # insmod mxser

	  to activate the modular driver. You may run "lsmod" to check
	  if "mxser.o" is activated.

       2. Create special files by executing "msmknod".
	  # cd /moxa/mxser/driver
	  # ./msmknod

	  Default major numbers for dial-in device and callout device are
	  174, 175. Msmknod will delete any special files occupying the same
	  device naming.

       3. Up to now, you may manually execute "insmod mxser" to activate
	  this driver and run "rmmod mxser" to remove it. However, it's
	  better to have a boot time configuration to eliminate manual
	  operation.
	  Boot time configuration can be achieved by rc file. Run following
	  command for setting rc files.

	  # cd /moxa/mxser/driver
	  # cp ./rc.mxser /etc/rc.d
	  # cd /etc/rc.d

	  You may have to modify part of the content in rc.mxser to specify
          parameters for ISA board. Please refer to rc.mxser for more detail.
          Find "rc.serial". If "rc.serial" doesn't exist, create it by vi.
	  Add "rc.mxser" in last line. Next, open rc.local by vi
	  and append following content.

	  if [ -f /etc/rc.d/rc.serial ]; then
	     sh /etc/rc.d/rc.serial
	  fi

       4. Reboot and check if mxser.o activated by "lsmod" command.
       5. If you'd like to drive Smartio ISA boards in the system, you'll
	  have to add parameter to specify CAP address of given board while
          activating "mxser.o". The format for parameters are as follows.

	  insmod mxser ioaddr=0x???,0x???,0x???,0x???
				|      |     |	  |
				|      |     |	  +- 4th ISA board
				|      |     +------ 3rd ISA board
				|      +------------ 2nd ISA board
				+------------------- 1st ISA board

   3.4 Static driver configuration

       1. Create link
	  # cd /usr/src/linux/drivers/char
	  # ln -s /moxa/mxser/driver/mxser.c mxser.c

       2. Add CAP address list for ISA boards
	  In module mode, the CAP address for ISA board is given by
	  parameter. In static driver configuration, you'll have to
	  assign it within driver's source code. If you will not
	  install any ISA boards, you may skip to next portion.
	  The instructions to modify driver source code are as
	  below.
	  a. # cd /moxa/mxser/driver
	     # vi mxser.c
	  b. Find the array mxserBoardCAP[] as below.

	     static int mxserBoardCAP[]
	     = {0x00, 0x00, 0x00, 0x00};

	  c. Change the address within this array using vi. For
	     example, to driver 2 ISA boards with CAP address
	     0x280 and 0x180 as 1st and 2nd board. Just to change
	     the source code as follows.

	     static int mxserBoardCAP[]
	     = {0x280, 0x180, 0x00, 0x00};

       3. Modify tty_io.c
	  # cd /usr/src/linux/drivers/char/
	  # vi tty_io.c
	    Find pty_init(), insert "mxser_init()" as

	    pty_init();
	    mxser_init();

       4. Modify tty.h
	  # cd /usr/src/linux/include/linux
	  # vi tty.h
	    Find extern int tty_init(void), insert "mxser_init()" as

	    extern int tty_init(void);
	    extern int mxser_init(void);
     
       5. Modify Makefile
	  # cd /usr/src/linux/drivers/char
	  # vi Makefile
	    Find L_OBJS := tty_io.o ...... random.o, add
	    "mxser.o" at last of this line as
	    L_OBJS := tty_io.o ....... mxser.o

       6. Rebuild kernel
	  The following are for Linux kernel rebuilding,for your reference only.
	  For appropriate details, please refer to the Linux document.

	  If 'lilo' utility is installed, please use 'make zlilo' to rebuild
	  kernel. If 'lilo' is not installed, please follow the following steps.

	   a. cd /usr/src/linux
	   b. make clean			     /* take a few minutes */
	   c. make bzImage		   /* take probably 10-20 minutes */
	   d. Backup original boot kernel.		  /* optional step */
	   e. cp /usr/src/linux/arch/i386/boot/bzImage /boot/vmlinuz
	   f. Please make sure the boot kernel (vmlinuz) is in the
	      correct position. If you use 'lilo' utility, you should
	      check /etc/lilo.conf 'image' item specified the path
	      which is the 'vmlinuz' path, or you will load wrong
	      (or old) boot kernel image (vmlinuz).
	   g. chmod 400 /vmlinuz
	   h. lilo
	   i. rdev -R /vmlinuz 1
	   j. sync

	  Note that if the result of "make zImage" is ERROR, then you have to
	  go back to Linux configuration Setup. Type "make config" in directory
	  /usr/src/linux or "setup".

	  Since system include file, /usr/src/linux/include/linux/interrupt.h,
	  is modified each time the MOXA driver is installed, kernel rebuilding
	  is inevitable. And it takes about 10 to 20 minutes depends on the
	  machine.

       7. Make utility
	  # cd /moxa/mxser/utility
	  # make install
       
       8. Make special file
          # cd /moxa/mxser/driver
          # ./msmknod

       9. Reboot

   3.5 Custom configuration
       Although this driver already provides you default configuration, you
       still can change the device name and major number.The instruction to
       change these parameters are shown as below.

       Change Device name
       ------------------
       If you'd like to use other device names instead of default naming
       convention, all you have to do is to modify the internal code
       within the shell script "msmknod". First, you have to open "msmknod"
       by vi. Locate each line contains "ttyM" and "cum" and change them
       to the device name you desired. "msmknod" creates the device names
       you need next time executed.

       Change Major number
       -------------------
       If major number 30 and 35 had been occupied, you may have to select
       2 free major numbers for this driver. There are 3 steps to change
       major numbers.

       1. Find free major numbers
	  In /proc/devices, you may find all the major numbers occupied
	  in the system. Please select 2 major numbers that are available.
	  e.g. 40, 45.
       2. Create special files
	  Run /moxa/mxser/driver/msmknod to create special files with
	  specified major numbers.
       3. Modify driver with new major number
	  Run vi to open /moxa/mxser/driver/mxser.c. Locate the line
	  contains "MXSERMAJOR". Change the content as below.
	  #define	  MXSERMAJOR		  40
	  #define	  MXSERCUMAJOR		  45
       4. Run # make install in /moxa/mxser/driver.

   3.6 Verify driver installation
       You may refer to /var/log/messages to check the latest status
       log reported by this driver whenever it's activated.
-----------------------------------------------------------------------------
4. Utilities
   There are 3 utilities contained in this driver. They are msdiag, msmon and
   msterm. These 3 utilities are released in form of source code. They should
   be compiled into executable file and copied into /usr/bin.

   msdiag - Diagnostic
   --------------------
   This utility provides the function to detect what Moxa Smartio multiport
   board exists in the system.

   msmon - Port Monitoring
   -----------------------
   This utility gives the user a quick view about all the MOXA ports'
   activities. One can easily learn each port's total received/transmitted
   (Rx/Tx) character count since the time when the monitoring is started.
   Rx/Tx throughputs per second are also reported in interval basis (e.g.
   the last 5 seconds) and in average basis (since the time the monitoring
   is started). You can reset all ports' count by <HOME> key. <+> <->
   (plus/minus) keys to change the displaying time interval. Press <ENTER>
   on the port, that cursor stay, to view the port's communication
   parameters, signal status, and input/output queue.

   msterm - Terminal Emulation
   ---------------------------
   This utility provides data sending and receiving ability of all tty ports,
   especially for MOXA ports. It is quite useful for testing simple
   application, for example, sending AT command to a modem connected to the
   port or used as a terminal for login purpose. Note that this is only a
   dumb terminal emulation without handling full screen operation.
-----------------------------------------------------------------------------
5. Setserial

   Supported Setserial parameters are listed as below.

   uart 	  set UART type(16450-->disable FIFO, 16550A-->enable FIFO)
   close_delay	  set the amount of time(in 1/100 of a second) that DTR
		  should be kept low while being closed.
   closing_wait   set the amount of time(in 1/100 of a second) that the
		  serial port should wait for data to be drained while
		  being closed, before the receiver is disable.
   spd_hi	  Use  57.6kb  when  the application requests 38.4kb.
   spd_vhi	  Use  115.2kb	when  the application requests 38.4kb.
   spd_normal	  Use  38.4kb  when  the application requests 38.4kb.

-----------------------------------------------------------------------------
6. Troubleshooting

   The boot time error messages and solutions are stated as clearly as
   possible. If all the possible solutions fail, please contact our technical
   support team to get more help.

   Error msg: More than 4 Moxa Smartio family boards found. Fifth board and
	      after are ignored.
   Solution:
   To avoid this problem, please unplug fifth and after board, because Moxa
   driver supports up to 4 boards.

   Error msg: Request_irq fail, IRQ(?) may be conflict with another device.
   Solution:
   Other PCI or ISA devices occupy the assigned IRQ. If you are not sure
   which device causes the situation,please check /proc/interrupts to find
   free IRQ and simply change another free IRQ for Moxa board.

   Error msg: Board #: C1xx Series(CAP=xxx) interrupt number invalid.
   Solution:
   Each port within the same multiport board shares the same IRQ. Please set
   one IRQ (IRQ doesn't equal to zero) for one Moxa board.

   Error msg: No interrupt vector be set for Moxa ISA board(CAP=xxx).
   Solution:
   Moxa ISA board needs an interrupt vector.Please refer to user's manual
   "Hardware Installation" chapter to set interrupt vector.

   Error msg: Couldn't install MOXA Smartio family driver!
   Solution:
   Load Moxa driver fail, the major number may conflict with other devices.
   Please refer to previous section 3.5 to change a free major number for
   Moxa driver.

   Error msg: Couldn't install MOXA Smartio family callout driver!
   Solution:
   Load Moxa callout driver fail, the callout device major number may
   conflict with other devices. Please refer to previous section 3.5 to
   change a free callout device major number for Moxa driver.
-----------------------------------------------------------------------------
934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197
/*
 *  linux/fs/open.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#include <linux/string.h>
#include <linux/mm.h>
#include <linux/file.h>
#include <linux/quotaops.h>
#include <linux/fsnotify.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/namei.h>
#include <linux/backing-dev.h>
#include <linux/capability.h>
#include <linux/security.h>
#include <linux/mount.h>
#include <linux/vfs.h>
#include <linux/fcntl.h>
#include <asm/uaccess.h>
#include <linux/fs.h>
#include <linux/personality.h>
#include <linux/pagemap.h>
#include <linux/syscalls.h>
#include <linux/rcupdate.h>
#include <linux/audit.h>
#include <linux/falloc.h>

int vfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	int retval = -ENODEV;

	if (dentry) {
		retval = -ENOSYS;
		if (dentry->d_sb->s_op->statfs) {
			memset(buf, 0, sizeof(*buf));
			retval = security_sb_statfs(dentry);
			if (retval)
				return retval;
			retval = dentry->d_sb->s_op->statfs(dentry, buf);
			if (retval == 0 && buf->f_frsize == 0)
				buf->f_frsize = buf->f_bsize;
		}
	}
	return retval;
}

EXPORT_SYMBOL(vfs_statfs);

static int vfs_statfs_native(struct dentry *dentry, struct statfs *buf)
{
	struct kstatfs st;
	int retval;

	retval = vfs_statfs(dentry, &st);
	if (retval)
		return retval;

	if (sizeof(*buf) == sizeof(st))
		memcpy(buf, &st, sizeof(st));
	else {
		if (sizeof buf->f_blocks == 4) {
			if ((st.f_blocks | st.f_bfree | st.f_bavail) &
			    0xffffffff00000000ULL)
				return -EOVERFLOW;
			/*
			 * f_files and f_ffree may be -1; it's okay to stuff
			 * that into 32 bits
			 */
			if (st.f_files != -1 &&
			    (st.f_files & 0xffffffff00000000ULL))
				return -EOVERFLOW;
			if (st.f_ffree != -1 &&
			    (st.f_ffree & 0xffffffff00000000ULL))
				return -EOVERFLOW;
		}

		buf->f_type = st.f_type;
		buf->f_bsize = st.f_bsize;
		buf->f_blocks = st.f_blocks;
		buf->f_bfree = st.f_bfree;
		buf->f_bavail = st.f_bavail;
		buf->f_files = st.f_files;
		buf->f_ffree = st.f_ffree;
		buf->f_fsid = st.f_fsid;
		buf->f_namelen = st.f_namelen;
		buf->f_frsize = st.f_frsize;
		memset(buf->f_spare, 0, sizeof(buf->f_spare));
	}
	return 0;
}

static int vfs_statfs64(struct dentry *dentry, struct statfs64 *buf)
{
	struct kstatfs st;
	int retval;

	retval = vfs_statfs(dentry, &st);
	if (retval)
		return retval;

	if (sizeof(*buf) == sizeof(st))
		memcpy(buf, &st, sizeof(st));
	else {
		buf->f_type = st.f_type;
		buf->f_bsize = st.f_bsize;
		buf->f_blocks = st.f_blocks;
		buf->f_bfree = st.f_bfree;
		buf->f_bavail = st.f_bavail;
		buf->f_files = st.f_files;
		buf->f_ffree = st.f_ffree;
		buf->f_fsid = st.f_fsid;
		buf->f_namelen = st.f_namelen;
		buf->f_frsize = st.f_frsize;
		memset(buf->f_spare, 0, sizeof(buf->f_spare));
	}
	return 0;
}

asmlinkage long sys_statfs(const char __user * path, struct statfs __user * buf)
{
	struct nameidata nd;
	int error;

	error = user_path_walk(path, &nd);
	if (!error) {
		struct statfs tmp;
		error = vfs_statfs_native(nd.path.dentry, &tmp);
		if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
			error = -EFAULT;
		path_put(&nd.path);
	}
	return error;
}


asmlinkage long sys_statfs64(const char __user *path, size_t sz, struct statfs64 __user *buf)
{
	struct nameidata nd;
	long error;

	if (sz != sizeof(*buf))
		return -EINVAL;
	error = user_path_walk(path, &nd);
	if (!error) {
		struct statfs64 tmp;
		error = vfs_statfs64(nd.path.dentry, &tmp);
		if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
			error = -EFAULT;
		path_put(&nd.path);
	}
	return error;
}


asmlinkage long sys_fstatfs(unsigned int fd, struct statfs __user * buf)
{
	struct file * file;
	struct statfs tmp;
	int error;

	error = -EBADF;
	file = fget(fd);
	if (!file)
		goto out;
	error = vfs_statfs_native(file->f_path.dentry, &tmp);
	if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
		error = -EFAULT;
	fput(file);
out:
	return error;
}

asmlinkage long sys_fstatfs64(unsigned int fd, size_t sz, struct statfs64 __user *buf)
{
	struct file * file;
	struct statfs64 tmp;
	int error;

	if (sz != sizeof(*buf))
		return -EINVAL;

	error = -EBADF;
	file = fget(fd);
	if (!file)
		goto out;
	error = vfs_statfs64(file->f_path.dentry, &tmp);
	if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
		error = -EFAULT;
	fput(file);
out:
	return error;
}

int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
	struct file *filp)
{
	int err;
	struct iattr newattrs;

	/* Not pretty: "inode->i_size" shouldn't really be signed. But it is. */
	if (length < 0)
		return -EINVAL;

	newattrs.ia_size = length;
	newattrs.ia_valid = ATTR_SIZE | time_attrs;
	if (filp) {
		newattrs.ia_file = filp;
		newattrs.ia_valid |= ATTR_FILE;
	}

	/* Remove suid/sgid on truncate too */
	newattrs.ia_valid |= should_remove_suid(dentry);

	mutex_lock(&dentry->d_inode->i_mutex);
	err = notify_change(dentry, &newattrs);
	mutex_unlock(&dentry->d_inode->i_mutex);
	return err;
}

static long do_sys_truncate(const char __user * path, loff_t length)
{
	struct nameidata nd;
	struct inode * inode;
	int error;

	error = -EINVAL;
	if (length < 0)	/* sorry, but loff_t says... */
		goto out;

	error = user_path_walk(path, &nd);
	if (error)
		goto out;
	inode = nd.path.dentry->d_inode;

	/* For directories it's -EISDIR, for other non-regulars - -EINVAL */
	error = -EISDIR;
	if (S_ISDIR(inode->i_mode))
		goto dput_and_out;

	error = -EINVAL;
	if (!S_ISREG(inode->i_mode))
		goto dput_and_out;

	error = vfs_permission(&nd, MAY_WRITE);
	if (error)
		goto dput_and_out;

	error = -EROFS;
	if (IS_RDONLY(inode))
		goto dput_and_out;

	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto dput_and_out;

	error = get_write_access(inode);
	if (error)
		goto dput_and_out;

	/*
	 * Make sure that there are no leases.  get_write_access() protects
	 * against the truncate racing with a lease-granting setlease().
	 */
	error = break_lease(inode, FMODE_WRITE);
	if (error)
		goto put_write_and_out;

	error = locks_verify_truncate(inode, NULL, length);
	if (!error) {
		DQUOT_INIT(inode);
		error = do_truncate(nd.path.dentry, length, 0, NULL);
	}

put_write_and_out:
	put_write_access(inode);
dput_and_out:
	path_put(&nd.path);
out:
	return error;
}

asmlinkage long sys_truncate(const char __user * path, unsigned long length)
{
	/* on 32-bit boxen it will cut the range 2^31--2^32-1 off */
	return do_sys_truncate(path, (long)length);
}

static long do_sys_ftruncate(unsigned int fd, loff_t length, int small)
{
	struct inode * inode;
	struct dentry *dentry;
	struct file * file;
	int error;

	error = -EINVAL;
	if (length < 0)
		goto out;
	error = -EBADF;
	file = fget(fd);
	if (!file)
		goto out;

	/* explicitly opened as large or we are on 64-bit box */
	if (file->f_flags & O_LARGEFILE)
		small = 0;

	dentry = file->f_path.dentry;
	inode = dentry->d_inode;
	error = -EINVAL;
	if (!S_ISREG(inode->i_mode) || !(file->f_mode & FMODE_WRITE))
		goto out_putf;

	error = -EINVAL;
	/* Cannot ftruncate over 2^31 bytes without large file support */
	if (small && length > MAX_NON_LFS)
		goto out_putf;

	error = -EPERM;
	if (IS_APPEND(inode))
		goto out_putf;

	error = locks_verify_truncate(inode, file, length);
	if (!error)
		error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, file);
out_putf:
	fput(file);
out:
	return error;
}

asmlinkage long sys_ftruncate(unsigned int fd, unsigned long length)
{
	long ret = do_sys_ftruncate(fd, length, 1);
	/* avoid REGPARM breakage on x86: */
	prevent_tail_call(ret);
	return ret;
}

/* LFS versions of truncate are only needed on 32 bit machines */
#if BITS_PER_LONG == 32
asmlinkage long sys_truncate64(const char __user * path, loff_t length)
{
	return do_sys_truncate(path, length);
}

asmlinkage long sys_ftruncate64(unsigned int fd, loff_t length)
{
	long ret = do_sys_ftruncate(fd, length, 0);
	/* avoid REGPARM breakage on x86: */
	prevent_tail_call(ret);
	return ret;
}
#endif

asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, loff_t len)
{
	struct file *file;
	struct inode *inode;
	long ret = -EINVAL;

	if (offset < 0 || len <= 0)
		goto out;

	/* Return error if mode is not supported */
	ret = -EOPNOTSUPP;
	if (mode && !(mode & FALLOC_FL_KEEP_SIZE))
		goto out;

	ret = -EBADF;
	file = fget(fd);
	if (!file)
		goto out;
	if (!(file->f_mode & FMODE_WRITE))
		goto out_fput;
	/*
	 * Revalidate the write permissions, in case security policy has
	 * changed since the files were opened.
	 */
	ret = security_file_permission(file, MAY_WRITE);
	if (ret)
		goto out_fput;

	inode = file->f_path.dentry->d_inode;

	ret = -ESPIPE;
	if (S_ISFIFO(inode->i_mode))
		goto out_fput;

	ret = -ENODEV;
	/*
	 * Let individual file system decide if it supports preallocation
	 * for directories or not.
	 */
	if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
		goto out_fput;

	ret = -EFBIG;
	/* Check for wrap through zero too */
	if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0))
		goto out_fput;

	if (inode->i_op && inode->i_op->fallocate)
		ret = inode->i_op->fallocate(inode, mode, offset, len);
	else
		ret = -EOPNOTSUPP;

out_fput:
	fput(file);
out:
	return ret;
}

/*
 * access() needs to use the real uid/gid, not the effective uid/gid.
 * We do this by temporarily clearing all FS-related capabilities and
 * switching the fsuid/fsgid around to the real ones.
 */
asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode)
{
	struct nameidata nd;
	int old_fsuid, old_fsgid;
	kernel_cap_t old_cap;
	int res;

	if (mode & ~S_IRWXO)	/* where's F_OK, X_OK, W_OK, R_OK? */
		return -EINVAL;

	old_fsuid = current->fsuid;
	old_fsgid = current->fsgid;
	old_cap = current->cap_effective;

	current->fsuid = current->uid;
	current->fsgid = current->gid;

	/*
	 * Clear the capabilities if we switch to a non-root user
	 *
	 * FIXME: There is a race here against sys_capset.  The
	 * capabilities can change yet we will restore the old
	 * value below.  We should hold task_capabilities_lock,
	 * but we cannot because user_path_walk can sleep.
	 */
	if (current->uid)
		cap_clear(current->cap_effective);
	else
		current->cap_effective = current->cap_permitted;

	res = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW|LOOKUP_ACCESS, &nd);
	if (res)
		goto out;

	res = vfs_permission(&nd, mode);
	/* SuS v2 requires we report a read only fs too */
	if(res || !(mode & S_IWOTH) ||
	   special_file(nd.path.dentry->d_inode->i_mode))
		goto out_path_release;

	if(IS_RDONLY(nd.path.dentry->d_inode))
		res = -EROFS;

out_path_release:
	path_put(&nd.path);
out:
	current->fsuid = old_fsuid;
	current->fsgid = old_fsgid;
	current->cap_effective = old_cap;

	return res;
}

asmlinkage long sys_access(const char __user *filename, int mode)
{
	return sys_faccessat(AT_FDCWD, filename, mode);
}

asmlinkage long sys_chdir(const char __user * filename)
{
	struct nameidata nd;
	int error;

	error = __user_walk(filename,
			    LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_CHDIR, &nd);
	if (error)
		goto out;

	error = vfs_permission(&nd, MAY_EXEC);
	if (error)
		goto dput_and_out;

	set_fs_pwd(current->fs, nd.path.mnt, nd.path.dentry);

dput_and_out:
	path_put(&nd.path);
out:
	return error;
}

asmlinkage long sys_fchdir(unsigned int fd)
{
	struct file *file;
	struct dentry *dentry;
	struct inode *inode;
	struct vfsmount *mnt;
	int error;

	error = -EBADF;
	file = fget(fd);
	if (!file)
		goto out;

	dentry = file->f_path.dentry;
	mnt = file->f_path.mnt;
	inode = dentry->d_inode;

	error = -ENOTDIR;
	if (!S_ISDIR(inode->i_mode))
		goto out_putf;

	error = file_permission(file, MAY_EXEC);
	if (!error)
		set_fs_pwd(current->fs, mnt, dentry);
out_putf:
	fput(file);
out:
	return error;
}

asmlinkage long sys_chroot(const char __user * filename)
{
	struct nameidata nd;
	int error;

	error = __user_walk(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY | LOOKUP_NOALT, &nd);
	if (error)
		goto out;

	error = vfs_permission(&nd, MAY_EXEC);
	if (error)
		goto dput_and_out;

	error = -EPERM;
	if (!capable(CAP_SYS_CHROOT))
		goto dput_and_out;

	set_fs_root(current->fs, nd.path.mnt, nd.path.dentry);
	set_fs_altroot();
	error = 0;
dput_and_out:
	path_put(&nd.path);
out:
	return error;
}

asmlinkage long sys_fchmod(unsigned int fd, mode_t mode)
{
	struct inode * inode;
	struct dentry * dentry;
	struct file * file;
	int err = -EBADF;
	struct iattr newattrs;

	file = fget(fd);
	if (!file)
		goto out;

	dentry = file->f_path.dentry;
	inode = dentry->d_inode;

	audit_inode(NULL, dentry);

	err = -EROFS;
	if (IS_RDONLY(inode))
		goto out_putf;
	err = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto out_putf;
	mutex_lock(&inode->i_mutex);
	if (mode == (mode_t) -1)
		mode = inode->i_mode;
	newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
	newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
	err = notify_change(dentry, &newattrs);
	mutex_unlock(&inode->i_mutex);

out_putf:
	fput(file);
out:
	return err;
}

asmlinkage long sys_fchmodat(int dfd, const char __user *filename,
			     mode_t mode)
{
	struct nameidata nd;
	struct inode * inode;
	int error;
	struct iattr newattrs;

	error = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW, &nd);
	if (error)
		goto out;
	inode = nd.path.dentry->d_inode;

	error = -EROFS;
	if (IS_RDONLY(inode))
		goto dput_and_out;

	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto dput_and_out;

	mutex_lock(&inode->i_mutex);
	if (mode == (mode_t) -1)
		mode = inode->i_mode;
	newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
	newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
	error = notify_change(nd.path.dentry, &newattrs);
	mutex_unlock(&inode->i_mutex);

dput_and_out:
	path_put(&nd.path);
out:
	return error;
}

asmlinkage long sys_chmod(const char __user *filename, mode_t mode)
{
	return sys_fchmodat(AT_FDCWD, filename, mode);
}

static int chown_common(struct dentry * dentry, uid_t user, gid_t group)
{
	struct inode * inode;
	int error;
	struct iattr newattrs;

	error = -ENOENT;
	if (!(inode = dentry->d_inode)) {
		printk(KERN_ERR "chown_common: NULL inode\n");
		goto out;
	}
	error = -EROFS;
	if (IS_RDONLY(inode))
		goto out;
	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto out;
	newattrs.ia_valid =  ATTR_CTIME;
	if (user != (uid_t) -1) {
		newattrs.ia_valid |= ATTR_UID;
		newattrs.ia_uid = user;
	}
	if (group != (gid_t) -1) {
		newattrs.ia_valid |= ATTR_GID;
		newattrs.ia_gid = group;
	}
	if (!S_ISDIR(inode->i_mode))
		newattrs.ia_valid |=
			ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
	mutex_lock(&inode->i_mutex);
	error = notify_change(dentry, &newattrs);
	mutex_unlock(&inode->i_mutex);
out:
	return error;
}

asmlinkage long sys_chown(const char __user * filename, uid_t user, gid_t group)
{
	struct nameidata nd;
	int error;

	error = user_path_walk(filename, &nd);
	if (error)
		goto out;
	error = chown_common(nd.path.dentry, user, group);
	path_put(&nd.path);
out:
	return error;
}

asmlinkage long sys_fchownat(int dfd, const char __user *filename, uid_t user,
			     gid_t group, int flag)
{
	struct nameidata nd;
	int error = -EINVAL;
	int follow;

	if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
		goto out;

	follow = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
	error = __user_walk_fd(dfd, filename, follow, &nd);
	if (error)
		goto out;
	error = chown_common(nd.path.dentry, user, group);
	path_put(&nd.path);
out:
	return error;
}

asmlinkage long sys_lchown(const char __user * filename, uid_t user, gid_t group)
{
	struct nameidata nd;
	int error;

	error = user_path_walk_link(filename, &nd);
	if (error)
		goto out;
	error = chown_common(nd.path.dentry, user, group);
	path_put(&nd.path);
out:
	return error;
}


asmlinkage long sys_fchown(unsigned int fd, uid_t user, gid_t group)
{
	struct file * file;
	int error = -EBADF;
	struct dentry * dentry;

	file = fget(fd);
	if (!file)
		goto out;

	dentry = file->f_path.dentry;
	audit_inode(NULL, dentry);
	error = chown_common(dentry, user, group);
	fput(file);
out:
	return error;
}

static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
					int flags, struct file *f,
					int (*open)(struct inode *, struct file *))
{
	struct inode *inode;
	int error;

	f->f_flags = flags;
	f->f_mode = ((flags+1) & O_ACCMODE) | FMODE_LSEEK |
				FMODE_PREAD | FMODE_PWRITE;
	inode = dentry->d_inode;
	if (f->f_mode & FMODE_WRITE) {
		error = get_write_access(inode);
		if (error)
			goto cleanup_file;
	}

	f->f_mapping = inode->i_mapping;
	f->f_path.dentry = dentry;
	f->f_path.mnt = mnt;
	f->f_pos = 0;
	f->f_op = fops_get(inode->i_fop);
	file_move(f, &inode->i_sb->s_files);

	error = security_dentry_open(f);
	if (error)
		goto cleanup_all;

	if (!open && f->f_op)
		open = f->f_op->open;
	if (open) {
		error = open(inode, f);
		if (error)
			goto cleanup_all;
	}

	f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);

	file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);

	/* NB: we're sure to have correct a_ops only after f_op->open */
	if (f->f_flags & O_DIRECT) {
		if (!f->f_mapping->a_ops ||
		    ((!f->f_mapping->a_ops->direct_IO) &&
		    (!f->f_mapping->a_ops->get_xip_page))) {
			fput(f);
			f = ERR_PTR(-EINVAL);
		}
	}

	return f;

cleanup_all:
	fops_put(f->f_op);
	if (f->f_mode & FMODE_WRITE)
		put_write_access(inode);
	file_kill(f);
	f->f_path.dentry = NULL;
	f->f_path.mnt = NULL;
cleanup_file:
	put_filp(f);
	dput(dentry);
	mntput(mnt);
	return ERR_PTR(error);
}

/*
 * Note that while the flag value (low two bits) for sys_open means:
 *	00 - read-only
 *	01 - write-only
 *	10 - read-write
 *	11 - special
 * it is changed into
 *	00 - no permissions needed
 *	01 - read-permission
 *	10 - write-permission
 *	11 - read-write
 * for the internal routines (ie open_namei()/follow_link() etc). 00 is
 * used by symlinks.
 */
static struct file *do_filp_open(int dfd, const char *filename, int flags,
				 int mode)
{
	int namei_flags, error;
	struct nameidata nd;

	namei_flags = flags;
	if ((namei_flags+1) & O_ACCMODE)
		namei_flags++;

	error = open_namei(dfd, filename, namei_flags, mode, &nd);
	if (!error)
		return nameidata_to_filp(&nd, flags);

	return ERR_PTR(error);
}

struct file *filp_open(const char *filename, int flags, int mode)
{
	return do_filp_open(AT_FDCWD, filename, flags, mode);
}
EXPORT_SYMBOL(filp_open);

/**
 * lookup_instantiate_filp - instantiates the open intent filp
 * @nd: pointer to nameidata
 * @dentry: pointer to dentry
 * @open: open callback
 *
 * Helper for filesystems that want to use lookup open intents and pass back
 * a fully instantiated struct file to the caller.
 * This function is meant to be called from within a filesystem's
 * lookup method.
 * Beware of calling it for non-regular files! Those ->open methods might block
 * (e.g. in fifo_open), leaving you with parent locked (and in case of fifo,
 * leading to a deadlock, as nobody can open that fifo anymore, because
 * another process to open fifo will block on locked parent when doing lookup).
 * Note that in case of error, nd->intent.open.file is destroyed, but the
 * path information remains valid.
 * If the open callback is set to NULL, then the standard f_op->open()
 * filesystem callback is substituted.
 */
struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
		int (*open)(struct inode *, struct file *))
{
	if (IS_ERR(nd->intent.open.file))
		goto out;
	if (IS_ERR(dentry))
		goto out_err;
	nd->intent.open.file = __dentry_open(dget(dentry), mntget(nd->path.mnt),
					     nd->intent.open.flags - 1,
					     nd->intent.open.file,
					     open);
out:
	return nd->intent.open.file;
out_err:
	release_open_intent(nd);
	nd->intent.open.file = (struct file *)dentry;
	goto out;
}
EXPORT_SYMBOL_GPL(lookup_instantiate_filp);

/**
 * nameidata_to_filp - convert a nameidata to an open filp.
 * @nd: pointer to nameidata
 * @flags: open flags
 *
 * Note that this function destroys the original nameidata
 */
struct file *nameidata_to_filp(struct nameidata *nd, int flags)
{
	struct file *filp;

	/* Pick up the filp from the open intent */
	filp = nd->intent.open.file;
	/* Has the filesystem initialised the file for us? */
	if (filp->f_path.dentry == NULL)
		filp = __dentry_open(nd->path.dentry, nd->path.mnt, flags, filp,
				     NULL);
	else
		path_put(&nd->path);
	return filp;
}

/*
 * dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an
 * error.
 */
struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
{
	int error;
	struct file *f;

	error = -ENFILE;
	f = get_empty_filp();
	if (f == NULL) {
		dput(dentry);
		mntput(mnt);
		return ERR_PTR(error);
	}

	return __dentry_open(dentry, mnt, flags, f, NULL);
}
EXPORT_SYMBOL(dentry_open);

/*
 * Find an empty file descriptor entry, and mark it busy.
 */
int get_unused_fd_flags(int flags)
{
	struct files_struct * files = current->files;
	int fd, error;
	struct fdtable *fdt;

  	error = -EMFILE;
	spin_lock(&files->file_lock);

repeat:
	fdt = files_fdtable(files);
	fd = find_next_zero_bit(fdt->open_fds->fds_bits, fdt->max_fds,
				files->next_fd);

	/*
	 * N.B. For clone tasks sharing a files structure, this test
	 * will limit the total number of files that can be opened.
	 */
	if (fd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
		goto out;

	/* Do we need to expand the fd array or fd set?  */
	error = expand_files(files, fd);
	if (error < 0)
		goto out;

	if (error) {
		/*
	 	 * If we needed to expand the fs array we
		 * might have blocked - try again.
		 */
		error = -EMFILE;
		goto repeat;
	}

	FD_SET(fd, fdt->open_fds);
	if (flags & O_CLOEXEC)
		FD_SET(fd, fdt->close_on_exec);
	else
		FD_CLR(fd, fdt->close_on_exec);
	files->next_fd = fd + 1;
#if 1
	/* Sanity check */
	if (fdt->fd[fd] != NULL) {
		printk(KERN_WARNING "get_unused_fd: slot %d not NULL!\n", fd);
		fdt->fd[fd] = NULL;
	}
#endif
	error = fd;

out:
	spin_unlock(&files->file_lock);
	return error;
}

int get_unused_fd(void)
{
	return get_unused_fd_flags(0);
}

EXPORT_SYMBOL(get_unused_fd);

static void __put_unused_fd(struct files_struct *files, unsigned int fd)
{
	struct fdtable *fdt = files_fdtable(files);
	__FD_CLR(fd, fdt->open_fds);
	if (fd < files->next_fd)
		files->next_fd = fd;
}

void put_unused_fd(unsigned int fd)
{
	struct files_struct *files = current->files;
	spin_lock(&files->file_lock);
	__put_unused_fd(files, fd);
	spin_unlock(&files->file_lock);
}

EXPORT_SYMBOL(put_unused_fd);

/*
 * Install a file pointer in the fd array.
 *
 * The VFS is full of places where we drop the files lock between
 * setting the open_fds bitmap and installing the file in the file
 * array.  At any such point, we are vulnerable to a dup2() race
 * installing a file in the array before us.  We need to detect this and
 * fput() the struct file we are about to overwrite in this case.
 *
 * It should never happen - if we allow dup2() do it, _really_ bad things
 * will follow.
 */

void fd_install(unsigned int fd, struct file *file)
{
	struct files_struct *files = current->files;
	struct fdtable *fdt;
	spin_lock(&files->file_lock);
	fdt = files_fdtable(files);
	BUG_ON(fdt->fd[fd] != NULL);
	rcu_assign_pointer(fdt->fd[fd], file);
	spin_unlock(&files->file_lock);
}

EXPORT_SYMBOL(fd_install);

long do_sys_open(int dfd, const char __user *filename, int flags, int mode)
{
	char *tmp = getname(filename);
	int fd = PTR_ERR(tmp);

	if (!IS_ERR(tmp)) {
		fd = get_unused_fd_flags(flags);
		if (fd >= 0) {
			struct file *f = do_filp_open(dfd, tmp, flags, mode);
			if (IS_ERR(f)) {
				put_unused_fd(fd);
				fd = PTR_ERR(f);
			} else {
				fsnotify_open(f->f_path.dentry);
				fd_install(fd, f);
			}
		}
		putname(tmp);
	}
	return fd;
}

asmlinkage long sys_open(const char __user *filename, int flags, int mode)
{
	long ret;

	if (force_o_largefile())
		flags |= O_LARGEFILE;

	ret = do_sys_open(AT_FDCWD, filename, flags, mode);
	/* avoid REGPARM breakage on x86: */
	prevent_tail_call(ret);
	return ret;
}

asmlinkage long sys_openat(int dfd, const char __user *filename, int flags,
			   int mode)
{
	long ret;

	if (force_o_largefile())
		flags |= O_LARGEFILE;

	ret = do_sys_open(dfd, filename, flags, mode);
	/* avoid REGPARM breakage on x86: */
	prevent_tail_call(ret);
	return ret;
}

#ifndef __alpha__

/*
 * For backward compatibility?  Maybe this should be moved
 * into arch/i386 instead?
 */
asmlinkage long sys_creat(const char __user * pathname, int mode)
{
	return sys_open(pathname, O_CREAT | O_WRONLY | O_TRUNC, mode);
}

#endif

/*
 * "id" is the POSIX thread ID. We use the
 * files pointer for this..
 */
int filp_close(struct file *filp, fl_owner_t id)
{
	int retval = 0;

	if (!file_count(filp)) {
		printk(KERN_ERR "VFS: Close: file count is 0\n");
		return 0;
	}

	if (filp->f_op && filp->f_op->flush)
		retval = filp->f_op->flush(filp, id);

	dnotify_flush(filp, id);
	locks_remove_posix(filp, id);
	fput(filp);
	return retval;
}

EXPORT_SYMBOL(filp_close);

/*
 * Careful here! We test whether the file pointer is NULL before
 * releasing the fd. This ensures that one clone task can't release
 * an fd while another clone is opening it.
 */
asmlinkage long sys_close(unsigned int fd)
{
	struct file * filp;
	struct files_struct *files = current->files;
	struct fdtable *fdt;
	int retval;

	spin_lock(&files->file_lock);
	fdt = files_fdtable(files);
	if (fd >= fdt->max_fds)
		goto out_unlock;
	filp = fdt->fd[fd];
	if (!filp)
		goto out_unlock;
	rcu_assign_pointer(fdt->fd[fd], NULL);
	FD_CLR(fd, fdt->close_on_exec);
	__put_unused_fd(files, fd);
	spin_unlock(&files->file_lock);
	retval = filp_close(filp, files);

	/* can't restart close syscall because file table entry was cleared */
	if (unlikely(retval == -ERESTARTSYS ||
		     retval == -ERESTARTNOINTR ||
		     retval == -ERESTARTNOHAND ||
		     retval == -ERESTART_RESTARTBLOCK))
		retval = -EINTR;

	return retval;

out_unlock:
	spin_unlock(&files->file_lock);
	return -EBADF;
}

EXPORT_SYMBOL(sys_close);

/*
 * This routine simulates a hangup on the tty, to arrange that users
 * are given clean terminals at login time.
 */
asmlinkage long sys_vhangup(void)
{
	if (capable(CAP_SYS_TTY_CONFIG)) {
		/* XXX: this needs locking */
		tty_vhangup(current->signal->tty);
		return 0;
	}
	return -EPERM;
}

/*
 * Called when an inode is about to be open.
 * We use this to disallow opening large files on 32bit systems if
 * the caller didn't specify O_LARGEFILE.  On 64bit systems we force
 * on this flag in sys_open.
 */
int generic_file_open(struct inode * inode, struct file * filp)
{
	if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
		return -EOVERFLOW;
	return 0;
}

EXPORT_SYMBOL(generic_file_open);

/*
 * This is used by subsystems that don't want seekable
 * file descriptors
 */
int nonseekable_open(struct inode *inode, struct file *filp)
{
	filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE);
	return 0;
}

EXPORT_SYMBOL(nonseekable_open);