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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
*
*/
#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);
struct file_operations affs_dir_operations = {
read: generic_read_dir,
readdir: affs_readdir,
fsync: file_fsync,
};
/*
* directories can handle most operations...
*/
struct inode_operations affs_dir_inode_operations = {
create: affs_create,
lookup: affs_lookup,
link: affs_link,
unlink: affs_unlink,
symlink: affs_symlink,
mkdir: affs_mkdir,
rmdir: affs_rmdir,
rename: affs_rename,
setattr: affs_notify_change,
};
static int
affs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct inode *inode = filp->f_dentry->d_inode;
struct super_block *sb = inode->i_sb;
struct buffer_head *dir_bh;
struct buffer_head *fh_bh;
unsigned char *name;
int namelen;
u32 i;
int hash_pos;
int chain_pos;
u32 f_pos;
u32 ino;
int stored;
int res;
pr_debug("AFFS: readdir(ino=%lu,f_pos=%lx)\n",inode->i_ino,(unsigned long)filp->f_pos);
stored = 0;
res = -EIO;
dir_bh = NULL;
fh_bh = NULL;
f_pos = filp->f_pos;
if (f_pos == 0) {
filp->private_data = (void *)0;
if (filldir(dirent, ".", 1, f_pos, inode->i_ino, DT_DIR) < 0)
return 0;
filp->f_pos = f_pos = 1;
stored++;
}
if (f_pos == 1) {
if (filldir(dirent, "..", 2, f_pos, filp->f_dentry->d_parent->d_inode->i_ino, DT_DIR) < 0)
return stored;
filp->f_pos = f_pos = 2;
stored++;
}
affs_lock_dir(inode);
chain_pos = (f_pos - 2) & 0xffff;
hash_pos = (f_pos - 2) >> 16;
if (chain_pos == 0xffff) {
affs_warning(sb, "readdir", "More than 65535 entries in chain");
chain_pos = 0;
hash_pos++;
filp->f_pos = ((hash_pos << 16) | chain_pos) + 2;
}
dir_bh = affs_bread(sb, inode->i_ino);
if (!dir_bh)
goto readdir_out;
/* If the directory hasn't changed since the last call to readdir(),
* we can jump directly to where we left off.
*/
ino = (u32)(long)filp->private_data;
if (ino && filp->f_version == inode->i_version) {
pr_debug("AFFS: readdir() left off=%d\n", ino);
goto inside;
}
ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[hash_pos]);
for (i = 0; ino && i < chain_pos; i++) {
fh_bh = affs_bread(sb, ino);
if (!fh_bh) {
affs_error(sb, "readdir","Cannot read block %d", i);
goto readdir_out;
}
ino = be32_to_cpu(AFFS_TAIL(sb, fh_bh)->hash_chain);
affs_brelse(fh_bh);
fh_bh = NULL;
}
if (ino)
goto inside;
hash_pos++;
for (; hash_pos < AFFS_SB->s_hashsize; hash_pos++) {
ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[hash_pos]);
if (!ino)
continue;
f_pos = (hash_pos << 16) + 2;
inside:
do {
fh_bh = affs_bread(sb, ino);
if (!fh_bh) {
affs_error(sb, "readdir","Cannot read block %d", ino);
goto readdir_done;
}
namelen = min(AFFS_TAIL(sb, fh_bh)->name[0], (u8)30);
name = AFFS_TAIL(sb, fh_bh)->name + 1;
pr_debug("AFFS: readdir(): filldir(\"%.*s\", ino=%u), hash=%d, f_pos=%x\n",
namelen, name, ino, hash_pos, f_pos);
if (filldir(dirent, name, namelen, f_pos, ino, DT_UNKNOWN) < 0)
goto readdir_done;
stored++;
f_pos++;
ino = be32_to_cpu(AFFS_TAIL(sb, fh_bh)->hash_chain);
affs_brelse(fh_bh);
fh_bh = NULL;
} while (ino);
}
readdir_done:
filp->f_pos = f_pos;
filp->f_version = inode->i_version;
filp->private_data = (void *)(long)ino;
res = stored;
readdir_out:
affs_brelse(dir_bh);
affs_brelse(fh_bh);
affs_unlock_dir(inode);
pr_debug("AFFS: readdir()=%d\n", stored);
return res;
}
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