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/*
* linux/fs/ufs/file.c
*
* Copyright (C) 1998
* Daniel Pirkl <daniel.pirkl@email.cz>
* Charles University, Faculty of Mathematics and Physics
*
* from
*
* linux/fs/ext2/file.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/fs/minix/file.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* ext2 fs regular file handling primitives
*/
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/ufs_fs.h>
#include <linux/fcntl.h>
#include <linux/sched.h>
#include <linux/stat.h>
#include <linux/locks.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#define NBUF 32
#define MIN(a,b) (((a)<(b))?(a):(b))
#define MAX(a,b) (((a)>(b))?(a):(b))
/*
* Make sure the offset never goes beyond the 32-bit mark..
*/
static long long ufs_file_lseek(
struct file *file,
long long offset,
int origin )
{
long long retval;
struct inode *inode = file->f_dentry->d_inode;
switch (origin) {
case 2:
offset += inode->i_size;
break;
case 1:
offset += file->f_pos;
}
retval = -EINVAL;
/* make sure the offset fits in 32 bits */
if (((unsigned long long) offset >> 32) == 0) {
if (offset != file->f_pos) {
file->f_pos = offset;
file->f_reada = 0;
file->f_version = ++event;
}
retval = offset;
}
return retval;
}
static inline void remove_suid(struct inode *inode)
{
unsigned int mode;
/* set S_IGID if S_IXGRP is set, and always set S_ISUID */
mode = (inode->i_mode & S_IXGRP)*(S_ISGID/S_IXGRP) | S_ISUID;
/* was any of the uid bits set? */
mode &= inode->i_mode;
if (mode && !suser()) {
inode->i_mode &= ~mode;
mark_inode_dirty(inode);
}
}
/*
* Write to a file (through the page cache).
*/
static ssize_t
ufs_file_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
{
ssize_t retval;
retval = generic_file_write(file, buf, count,
ppos, block_write_partial_page);
if (retval > 0) {
struct inode *inode = file->f_dentry->d_inode;
remove_suid(inode);
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
mark_inode_dirty(inode);
}
return retval;
}
/*
* Called when an inode is released. Note that this is different
* from ufs_open: open gets called at every open, but release
* gets called only when /all/ the files are closed.
*/
static int ufs_release_file (struct inode * inode, struct file * filp)
{
return 0;
}
/*
* We have mostly NULL's here: the current defaults are ok for
* the ufs filesystem.
*/
static struct file_operations ufs_file_operations = {
ufs_file_lseek, /* lseek */
generic_file_read, /* read */
ufs_file_write, /* write */
NULL, /* readdir - bad */
NULL, /* poll - default */
NULL, /* ioctl */
generic_file_mmap, /* mmap */
NULL, /* no special open is needed */
NULL, /* flush */
ufs_release_file, /* release */
NULL, /* fsync */
NULL, /* fasync */
NULL, /* check_media_change */
NULL /* revalidate */
};
struct inode_operations ufs_file_inode_operations = {
&ufs_file_operations,/* default file operations */
NULL, /* create */
NULL, /* lookup */
NULL, /* link */
NULL, /* unlink */
NULL, /* symlink */
NULL, /* mkdir */
NULL, /* rmdir */
NULL, /* mknod */
NULL, /* rename */
NULL, /* readlink */
NULL, /* follow_link */
ufs_getfrag_block, /* get_block */
block_read_full_page, /* readpage */
block_write_full_page, /* writepage */
block_flushpage, /* flushpage */
ufs_truncate, /* truncate */
NULL, /* permission */
NULL, /* smap */
NULL /* revalidate */
};
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