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/*
* linux/fs/efs/namei.c
*
* Copyright (C) 1998 Mike Shaver
*
* Portions derived from work (C) 1995,1996 Christian Vogelgsang.
* ``Inspired by'' fs/minix/namei.c.
*/
#include <linux/efs_fs.h>
#include <linux/errno.h>
static struct buffer_head *
efs_find_entry(struct inode *dir, const char *oname, int onamelen,
struct efs_dir_entry **res_dir)
{
struct buffer_head *bh;
struct efs_sb_info *sbi;
struct efs_dirblk *dirblk;
__u32 offset, block, maxblk;
__u16 i, namelen;
char *name;
*res_dir = NULL;
if (!dir || !dir->i_sb)
return NULL;
sbi = &dir->i_sb->u.efs_sb;
bh = NULL;
block = offset = 0;
maxblk = dir->i_size >> EFS_BLOCK_SIZE_BITS;
DB(("EFS: dir has %d blocks\n", maxblk));
for (block = 0; block < maxblk; block++) {
bh = bread(dir->i_dev, efs_bmap(dir, block), EFS_BLOCK_SIZE);
if (!bh) {
DB(("EFS: find_entry: skip blk %d (ino %#lx): bread\n",
block, dir->i_ino));
continue;
}
dirblk = (struct efs_dirblk *)bh->b_data;
if (efs_swab32(dirblk->db_magic) != EFS_DIRBLK_MAGIC) {
printk("EFS: dirblk %d (ino %#lx) has bad magic (%#x)!\n",
block, dir->i_ino, efs_swab32(dirblk->db_magic));
brelse(bh);
continue;
}
DB(("EFS: db %d has %d entries\n", block, dirblk->db_slots));
for (i = 0; i < dirblk->db_slots; i++) {
struct efs_dir_entry *dent;
__u16 off = EFS_SLOT2OFF(dirblk, i);
if (!off) {
DB(("skipping empty slot %d\n", i));
continue; /* skip empty slot */
}
dent = EFS_DENT4OFF(dirblk, off);
namelen = dent->d_namelen;
name = dent->d_name;
if ((namelen == onamelen) &&
!memcmp(oname, name, onamelen)) {
*res_dir = dent;
return bh;
}
}
brelse(bh);
}
DB(("EFS: find_entry didn't find inode for \"%s\"/%d\n",
oname, onamelen));
return NULL;
}
int
efs_lookup(struct inode *dir, struct dentry *dentry)
{
struct buffer_head *bh;
struct inode *in = NULL;
struct efs_dir_entry *dent;
bh = efs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &dent);
if (bh) {
int ino = efs_swab32(dent->ud_inum.l);
brelse(bh);
in = iget(dir->i_sb, ino);
if (!in)
return -EACCES;
}
d_add(dentry, in);
return 0;
}
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