From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA83AC55178 for ; Tue, 3 Nov 2020 15:55:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5CCD922264 for ; Tue, 3 Nov 2020 15:55:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hsIil1JJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727921AbgKCPz2 (ORCPT ); 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Tue, 3 Nov 2020 15:55:23 +0000 (UTC) Received: from [172.16.176.1] (ovpn-64-2.rdu2.redhat.com [10.10.64.2]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C76805D9CC; Tue, 3 Nov 2020 15:55:22 +0000 (UTC) From: "Benjamin Coddington" To: trondmy@kernel.org Cc: linux-nfs@vger.kernel.org Subject: Re: [PATCH v2 05/16] NFS: Don't discard readdir results Date: Tue, 03 Nov 2020 10:55:21 -0500 Message-ID: In-Reply-To: <20201103153329.531942-6-trondmy@kernel.org> References: <20201103153329.531942-1-trondmy@kernel.org> <20201103153329.531942-2-trondmy@kernel.org> <20201103153329.531942-3-trondmy@kernel.org> <20201103153329.531942-4-trondmy@kernel.org> <20201103153329.531942-5-trondmy@kernel.org> <20201103153329.531942-6-trondmy@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; format=flowed X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On 3 Nov 2020, at 10:33, trondmy@kernel.org wrote: > From: Trond Myklebust > > If a readdir call returns more data than we can fit into one page > cache page, then allocate a new one for that data rather than > discarding the data. > > Signed-off-by: Trond Myklebust > --- > fs/nfs/dir.c | 46 ++++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 42 insertions(+), 4 deletions(-) > > diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c > index b4861a33ad60..788c2a2eeaa3 100644 > --- a/fs/nfs/dir.c > +++ b/fs/nfs/dir.c > @@ -321,6 +321,26 @@ static void nfs_readdir_page_set_eof(struct page > *page) > kunmap_atomic(array); > } > > +static void nfs_readdir_page_unlock_and_put(struct page *page) > +{ > + unlock_page(page); > + put_page(page); > +} > + > +static struct page *nfs_readdir_page_get_next(struct address_space > *mapping, > + pgoff_t index, u64 cookie) > +{ > + struct page *page; > + > + page = nfs_readdir_page_get_locked(mapping, index, cookie); > + if (page) { > + if (nfs_readdir_page_last_cookie(page) == cookie) > + return page; > + nfs_readdir_page_unlock_and_put(page); > + } > + return NULL; > +} > + > static inline > int is_32bit_api(void) > { > @@ -638,13 +658,15 @@ void nfs_prime_dcache(struct dentry *parent, > struct nfs_entry *entry, > } > > /* Perform conversion from xdr to cache array */ > -static > -int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct > nfs_entry *entry, > - struct page **xdr_pages, struct page *page, unsigned int buflen) > +static int nfs_readdir_page_filler(struct nfs_readdir_descriptor > *desc, > + struct nfs_entry *entry, > + struct page **xdr_pages, > + struct page *fillme, unsigned int buflen) > { > + struct address_space *mapping = desc->file->f_mapping; > struct xdr_stream stream; > struct xdr_buf buf; > - struct page *scratch; > + struct page *scratch, *new, *page = fillme; > int status; > > scratch = alloc_page(GFP_KERNEL); > @@ -667,6 +689,19 @@ int > nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct > nfs_entry *en > desc->dir_verifier); > > status = nfs_readdir_add_to_array(entry, page); > + if (status != -ENOSPC) > + continue; > + > + if (page->mapping != mapping) > + break; ^^ How can this happen? Ben