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/*
* linux/fs/affs/dir.c
*
* (c) 1996 Hans-Joachim Widmaier - Rewritten
*
* (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
*
* (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
*
* (C) 1991 Linus Torvalds - minix filesystem
*
* affs directory handling functions
*
*/
#define DEBUG 0
#include <asm/uaccess.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/affs_fs.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/amigaffs.h>
static int affs_readdir(struct file *, void *, filldir_t);
static ssize_t affs_dir_read(struct file *, char *, size_t, loff_t *);
static struct file_operations affs_dir_operations = {
NULL, /* lseek - default */
affs_dir_read, /* read */
NULL, /* write - bad */
affs_readdir, /* readdir */
NULL, /* poll - default */
NULL, /* ioctl - default */
NULL, /* mmap */
NULL, /* no special open code */
NULL, /* flush */
NULL, /* no special release code */
file_fsync /* default fsync */
};
/*
* directories can handle most operations...
*/
struct inode_operations affs_dir_inode_operations = {
&affs_dir_operations, /* default directory file-ops */
affs_create, /* create */
affs_lookup, /* lookup */
affs_link, /* link */
affs_unlink, /* unlink */
affs_symlink, /* symlink */
affs_mkdir, /* mkdir */
affs_rmdir, /* rmdir */
NULL, /* mknod */
affs_rename, /* rename */
NULL, /* readlink */
NULL, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
NULL, /* bmap */
NULL, /* truncate */
NULL, /* permissions */
NULL, /* smap */
NULL, /* updatepage */
NULL /* revalidate */
};
static ssize_t
affs_dir_read(struct file *filp, char *buf, size_t count, loff_t *ppos)
{
return -EISDIR;
}
static int
affs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
int j, namelen;
s32 i;
int hash_pos;
int chain_pos;
unsigned long ino;
int stored;
unsigned char *name;
struct buffer_head *dir_bh;
struct buffer_head *fh_bh;
struct inode *dir;
struct inode *inode = filp->f_dentry->d_inode;
pr_debug("AFFS: readdir(ino=%lu,f_pos=%lu)\n",inode->i_ino,(unsigned long)filp->f_pos);
stored = 0;
dir_bh = NULL;
fh_bh = NULL;
dir = NULL;
ino = inode->i_ino;
if (filp->f_pos == 0) {
filp->private_data = (void *)0;
if (filldir(dirent,".",1,filp->f_pos,inode->i_ino) < 0) {
return 0;
}
++filp->f_pos;
stored++;
}
if (filp->f_pos == 1) {
if (filldir(dirent,"..",2,filp->f_pos,affs_parent_ino(inode)) < 0) {
return stored;
}
filp->f_pos = 2;
stored++;
}
chain_pos = (filp->f_pos - 2) & 0xffff;
hash_pos = (filp->f_pos - 2) >> 16;
if (chain_pos == 0xffff) {
affs_warning(inode->i_sb,"readdir","More than 65535 entries in chain");
chain_pos = 0;
hash_pos++;
filp->f_pos = ((hash_pos << 16) | chain_pos) + 2;
}
if (!(dir_bh = affs_bread(inode->i_dev,inode->i_ino,
AFFS_I2BSIZE(inode))))
goto readdir_done;
while (1) {
while (hash_pos < AFFS_I2HSIZE(inode) &&
!((struct dir_front *)dir_bh->b_data)->hashtable[hash_pos])
hash_pos++;
if (hash_pos >= AFFS_I2HSIZE(inode))
break;
i = be32_to_cpu(((struct dir_front *)dir_bh->b_data)->hashtable[hash_pos]);
j = chain_pos;
/* If the directory hasn't changed since the last call to readdir(),
* we can jump directly to where we left off.
*/
if (filp->private_data && filp->f_version == inode->i_version) {
i = (s32)filp->private_data;
j = 0;
pr_debug("AFFS: readdir() left off=%d\n",i);
}
filp->f_version = inode->i_version;
pr_debug("AFFS: hash_pos=%d chain_pos=%d\n",hash_pos,chain_pos);
while (i) {
if (!(fh_bh = affs_bread(inode->i_dev,i,AFFS_I2BSIZE(inode)))) {
affs_error(inode->i_sb,"readdir","Cannot read block %d",i);
goto readdir_done;
}
ino = i;
i = be32_to_cpu(FILE_END(fh_bh->b_data,inode)->hash_chain);
if (j == 0)
break;
affs_brelse(fh_bh);
fh_bh = NULL;
j--;
}
if (fh_bh) {
namelen = affs_get_file_name(AFFS_I2BSIZE(inode),fh_bh->b_data,&name);
pr_debug("AFFS: readdir(): filldir(\"%.*s\",ino=%lu), i=%d\n",
namelen,name,ino,i);
filp->private_data = (void *)ino;
if (filldir(dirent,name,namelen,filp->f_pos,ino) < 0)
goto readdir_done;
filp->private_data = (void *)i;
affs_brelse(fh_bh);
fh_bh = NULL;
stored++;
}
if (i == 0) {
hash_pos++;
chain_pos = 0;
} else
chain_pos++;
filp->f_pos = ((hash_pos << 16) | chain_pos) + 2;
}
readdir_done:
affs_brelse(dir_bh);
affs_brelse(fh_bh);
pr_debug("AFFS: readdir()=%d\n",stored);
return stored;
}
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