diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 93c6f22cdc62..3f70697729d8 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -937,11 +937,28 @@ static int find_and_lock_cache_page(struct nfs_readdir_descriptor *desc) return res; } +static bool nfs_readdir_dont_search_cache(struct nfs_readdir_descriptor *desc) +{ + struct address_space *mapping = desc->file->f_mapping; + struct inode *dir = file_inode(desc->file); + unsigned int dtsize = NFS_SERVER(dir)->dtsize; + loff_t size = i_size_read(dir); + + /* + * Default to uncached readdir if the page cache is empty, and + * we're looking for a non-zero cookie in a large directory. + */ + return desc->dir_cookie != 0 && mapping->nrpages == 0 && size > dtsize; +} + /* Search for desc->dir_cookie from the beginning of the page cache */ static int readdir_search_pagecache(struct nfs_readdir_descriptor *desc) { int res; + if (nfs_readdir_dont_search_cache(desc)) + return -EBADCOOKIE; + do { if (desc->page_index == 0) { desc->current_index = 0;