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/*
* file.c
*
* Copyright (c) 1999 Al Smith
*
* Portions derived from work (c) 1995,1996 Christian Vogelgsang.
*/
#include <linux/efs_fs.h>
static struct file_operations efs_file_operations = {
NULL, /* lseek */
generic_file_read, /* read */
NULL, /* write */
NULL, /* readdir */
NULL, /* poll */
NULL, /* ioctl */
generic_file_mmap, /* mmap */
NULL, /* open */
NULL, /* flush */
NULL, /* release */
NULL, /* fsync */
NULL, /* fasync */
NULL, /* check_media_change */
NULL /* revalidate */
};
struct inode_operations efs_file_inode_operations = {
&efs_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 */
generic_readpage, /* readpage */
NULL, /* writepage */
efs_bmap, /* bmap */
NULL, /* truncate */
NULL, /* permission */
NULL /* smap */
};
int efs_bmap(struct inode *inode, efs_block_t block) {
if (block < 0) {
printk(KERN_WARNING "EFS: bmap(): block < 0\n");
return 0;
}
/* are we about to read past the end of a file ? */
if (!(block < inode->i_blocks)) {
#ifdef DEBUG
/*
* i have no idea why this happens as often as it does
*/
printk(KERN_WARNING "EFS: bmap(): block %d >= %ld (filesize %ld)\n",
block,
inode->i_blocks,
inode->i_size);
#endif
return 0;
}
return efs_map_block(inode, block);
}
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