mirror of
				https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
				synced 2025-10-31 04:31:19 +00:00 
			
		
		
		
	 e7ec952f6a
			
		
	
	
		e7ec952f6a
		
	
	
	
	
		
			
			Only readdir() really needed it, and that's easily fixable by switch to generic_file_llseek() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
		
			
				
	
	
		
			119 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			119 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * namei.c
 | |
|  *
 | |
|  * Copyright (c) 1999 Al Smith
 | |
|  *
 | |
|  * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
 | |
|  */
 | |
| 
 | |
| #include <linux/buffer_head.h>
 | |
| #include <linux/string.h>
 | |
| #include <linux/exportfs.h>
 | |
| #include "efs.h"
 | |
| 
 | |
| 
 | |
| static efs_ino_t efs_find_entry(struct inode *inode, const char *name, int len) {
 | |
| 	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 (inode->i_size & (EFS_DIRBSIZE-1))
 | |
| 		printk(KERN_WARNING "EFS: WARNING: find_entry(): directory size not a multiple of EFS_DIRBSIZE\n");
 | |
| 
 | |
| 	for(block = 0; block < inode->i_blocks; block++) {
 | |
| 
 | |
| 		bh = sb_bread(inode->i_sb, efs_bmap(inode, block));
 | |
| 		if (!bh) {
 | |
| 			printk(KERN_ERR "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(KERN_ERR "EFS: find_entry(): 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);
 | |
| }
 | |
| 
 | |
| struct dentry *efs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) {
 | |
| 	efs_ino_t inodenum;
 | |
| 	struct inode * inode = NULL;
 | |
| 
 | |
| 	inodenum = efs_find_entry(dir, dentry->d_name.name, dentry->d_name.len);
 | |
| 	if (inodenum) {
 | |
| 		inode = efs_iget(dir->i_sb, inodenum);
 | |
| 		if (IS_ERR(inode))
 | |
| 			return ERR_CAST(inode);
 | |
| 	}
 | |
| 
 | |
| 	return d_splice_alias(inode, dentry);
 | |
| }
 | |
| 
 | |
| static struct inode *efs_nfs_get_inode(struct super_block *sb, u64 ino,
 | |
| 		u32 generation)
 | |
| {
 | |
| 	struct inode *inode;
 | |
| 
 | |
| 	if (ino == 0)
 | |
| 		return ERR_PTR(-ESTALE);
 | |
| 	inode = efs_iget(sb, ino);
 | |
| 	if (IS_ERR(inode))
 | |
| 		return ERR_CAST(inode);
 | |
| 
 | |
| 	if (generation && inode->i_generation != generation) {
 | |
| 		iput(inode);
 | |
| 		return ERR_PTR(-ESTALE);
 | |
| 	}
 | |
| 
 | |
| 	return inode;
 | |
| }
 | |
| 
 | |
| struct dentry *efs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 | |
| 		int fh_len, int fh_type)
 | |
| {
 | |
| 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 | |
| 				    efs_nfs_get_inode);
 | |
| }
 | |
| 
 | |
| struct dentry *efs_fh_to_parent(struct super_block *sb, struct fid *fid,
 | |
| 		int fh_len, int fh_type)
 | |
| {
 | |
| 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 | |
| 				    efs_nfs_get_inode);
 | |
| }
 | |
| 
 | |
| struct dentry *efs_get_parent(struct dentry *child)
 | |
| {
 | |
| 	struct dentry *parent = ERR_PTR(-ENOENT);
 | |
| 	efs_ino_t ino;
 | |
| 
 | |
| 	ino = efs_find_entry(child->d_inode, "..", 2);
 | |
| 	if (ino)
 | |
| 		parent = d_obtain_alias(efs_iget(child->d_inode->i_sb, ino));
 | |
| 
 | |
| 	return parent;
 | |
| }
 |