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/*
* namei.c
*
* Copyright (c) 1999 Al Smith
*
* Portions derived from work (c) 1995,1996 Christian Vogelgsang.
*/
#include <linux/efs.h>
/* search an efs directory inode for the given name */
static uint32_t efs_find_entry(struct inode *inode, const char *name, int len) {
struct efs_in_info *ini = (struct efs_in_info *) &inode->u.generic_ip;
struct buffer_head *bh;
int slot, namelen;
char *nameptr;
struct efs_dir *dirblock;
struct efs_dentry *dirslot;
efs_ino_t inodenum;
efs_block_t block;
if (ini->numextents != 1)
printk("EFS: WARNING: readdir(): more than one extent\n");
if (inode->i_size & (EFS_BLOCKSIZE-1))
printk("EFS: WARNING: readdir(): directory size not a multiple of EFS_BLOCKSIZE\n");
for(block = 0; block <= inode->i_blocks; block++) {
bh = bread(inode->i_dev, efs_bmap(inode, block), EFS_BLOCKSIZE);
if (!bh) {
printk("EFS: find_entry(): failed to read dir block %d\n", block);
return 0;
}
dirblock = (struct efs_dir *) bh->b_data;
if (be16_to_cpu(dirblock->magic) != EFS_DIRBLK_MAGIC) {
printk("EFS: readdir(): invalid directory block\n");
brelse(bh);
return(0);
}
for(slot = 0; slot < dirblock->slots; slot++) {
dirslot = (struct efs_dentry *) (((char *) bh->b_data) + EFS_SLOTAT(dirblock, slot));
namelen = dirslot->namelen;
nameptr = dirslot->name;
if ((namelen == len) && (!memcmp(name, nameptr, len))) {
inodenum = be32_to_cpu(dirslot->inode);
brelse(bh);
return(inodenum);
}
}
brelse(bh);
}
return(0);
}
/* get inode associated with directory entry */
int efs_lookup(struct inode *dir, struct dentry *dentry) {
int ino;
struct inode * inode;
if (!dir || !S_ISDIR(dir->i_mode)) return -ENOENT;
inode = NULL;
ino = efs_find_entry(dir, dentry->d_name.name, dentry->d_name.len);
if (ino) {
if (!(inode = iget(dir->i_sb, ino)))
return -EACCES;
}
d_add(dentry, inode);
return 0;
}
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