From patchwork Tue Nov 10 21:37:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 11895431 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4B0521391 for ; Tue, 10 Nov 2020 21:47:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2ADFD20797 for ; Tue, 10 Nov 2020 21:47:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="sAJkqaqT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731919AbgKJVr6 (ORCPT ); Tue, 10 Nov 2020 16:47:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:43122 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731907AbgKJVr5 (ORCPT ); Tue, 10 Nov 2020 16:47:57 -0500 Received: from localhost.localdomain (c-68-36-133-222.hsd1.mi.comcast.net [68.36.133.222]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7CFDE207D3 for ; Tue, 10 Nov 2020 21:47:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605044876; bh=LMQ0LtZPoruXhLjZLJyzXkABPdt1aAjPemM2uP8sHOo=; h=From:To:Subject:Date:In-Reply-To:References:From; b=sAJkqaqTvYD0jSr1nr85q5c/zSAVaStF1b04T2cUfCx43R3ELBZ3bRntUDGqRxiQ8 AqdHN9bmJ3yDRuezwwwjuzYR2+9K1NArRCysgou2eG0FKWtO3anodN+WtxTCudvR0W iNFmz3uql0swEHLI5w3hoQ0IIfyZ0GwDlPt5me1g= From: trondmy@kernel.org To: linux-nfs@vger.kernel.org Subject: [PATCH v5 08/22] NFS: Don't discard readdir results Date: Tue, 10 Nov 2020 16:37:27 -0500 Message-Id: <20201110213741.860745-9-trondmy@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201110213741.860745-8-trondmy@kernel.org> References: <20201110213741.860745-1-trondmy@kernel.org> <20201110213741.860745-2-trondmy@kernel.org> <20201110213741.860745-3-trondmy@kernel.org> <20201110213741.860745-4-trondmy@kernel.org> <20201110213741.860745-5-trondmy@kernel.org> <20201110213741.860745-6-trondmy@kernel.org> <20201110213741.860745-7-trondmy@kernel.org> <20201110213741.860745-8-trondmy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org 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 Reviewed-by: Benjamin Coddington Tested-by: Benjamin Coddington --- 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 842f69120a01..f7248145c333 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -320,6 +320,26 @@ 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) { @@ -637,13 +657,15 @@ 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); @@ -666,6 +688,19 @@ 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; + new = nfs_readdir_page_get_next(mapping, page->index + 1, + entry->prev_cookie); + if (!new) + break; + if (page != fillme) + nfs_readdir_page_unlock_and_put(page); + page = new; + status = nfs_readdir_add_to_array(entry, page); } while (!status && !entry->eof); switch (status) { @@ -681,6 +716,9 @@ int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *en break; } + if (page != fillme) + nfs_readdir_page_unlock_and_put(page); + put_page(scratch); return status; }