NFS: Fix a readdir/lookup inefficiency.

Make sure that nfs_readdir_lookup() handles negative dentries correctly.
If d_lookup() returns a negative dentry, then we need to d_drop() that
since readdir shows that it should be positive.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2007-01-15 13:56:29 -05:00
parent ccfeb50623
commit df1d5d23d3
1 changed files with 8 additions and 2 deletions

View File

@ -1123,8 +1123,14 @@ static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
}
name.hash = full_name_hash(name.name, name.len);
dentry = d_lookup(parent, &name);
if (dentry != NULL)
return dentry;
if (dentry != NULL) {
/* Is this a positive dentry? */
if (dentry->d_inode != NULL)
return dentry;
/* No, so d_drop to allow one to be created */
d_drop(dentry);
dput(dentry);
}
if (!desc->plus || !(entry->fattr->valid & NFS_ATTR_FATTR))
return NULL;
/* Note: caller is already holding the dir->i_mutex! */