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=-9.8 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, UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=unavailable 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 20471C43457 for ; Wed, 14 Oct 2020 16:35:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A84F120B1F for ; Wed, 14 Oct 2020 16:35:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="wvB6xYwb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731124AbgJNQfz (ORCPT ); Wed, 14 Oct 2020 12:35:55 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:44978 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727020AbgJNQfy (ORCPT ); Wed, 14 Oct 2020 12:35:54 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09EGUK9h088193; Wed, 14 Oct 2020 16:35:50 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=80XHxqPbf1mTULW9cTZ44rDWhSCJ9qRVBLotqhPfHuw=; b=wvB6xYwbbSqwVnYr9TDYAtQw77RWPaKNN0QHBGKlrl5JxQksIGCYmKRC2rWAL4haLhpY +iAt901UE7MUocO5OdtT8cC1KOQCQmTpNXGbDw7F7Ck6o0xIhPPsL7VsWHJQ9EkQ7Ntx cup1mQ23wl7AGNAHANQFJQUS3PjoQI18sZIiTiLoVuvTiWwC7VUICZekOd13wM4+ftRx 5S82yJbhUAfPC5MJ4jB5fj130LG7k91W/Ts+sLDzj3r4Fnn6TSKyWA3Av/qc+0Cn/a5x am5e2eAE93tTipeutRUIjdp9awBOPg0AJ45iPzHUEYkDdlr5iiAccVv/mduA/WKwdbVQ Bw== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by aserp2120.oracle.com with ESMTP id 3434wkrjg0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 14 Oct 2020 16:35:50 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09EGVERk179032; Wed, 14 Oct 2020 16:33:50 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserp3020.oracle.com with ESMTP id 343pv0k44g-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 14 Oct 2020 16:33:50 +0000 Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 09EGXnU3032612; Wed, 14 Oct 2020 16:33:49 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 14 Oct 2020 09:33:48 -0700 Date: Wed, 14 Oct 2020 09:33:47 -0700 From: "Darrick J. Wong" To: "Matthew Wilcox (Oracle)" Cc: linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 05/14] iomap: Support THPs in invalidatepage Message-ID: <20201014163347.GI9832@magnolia> References: <20201014030357.21898-1-willy@infradead.org> <20201014030357.21898-6-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201014030357.21898-6-willy@infradead.org> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9773 signatures=668681 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=904 mlxscore=0 spamscore=0 adultscore=0 suspectscore=1 phishscore=0 bulkscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010140117 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9773 signatures=668681 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 lowpriorityscore=0 mlxscore=0 malwarescore=0 phishscore=0 suspectscore=1 impostorscore=0 clxscore=1015 spamscore=0 priorityscore=1501 bulkscore=0 adultscore=0 mlxlogscore=921 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010140117 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Wed, Oct 14, 2020 at 04:03:48AM +0100, Matthew Wilcox (Oracle) wrote: > If we're punching a hole in a THP, we need to remove the per-page > iomap data as the THP is about to be split and each page will need > its own. This means that writepage can now come across a page with > no iop allocated, so remove the assertion that there is already one, > and just create one (with the uptodate bits set) if there isn't one. > > Signed-off-by: Matthew Wilcox (Oracle) > --- > fs/iomap/buffered-io.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c > index 95ac66731297..4633ebd03a3f 100644 > --- a/fs/iomap/buffered-io.c > +++ b/fs/iomap/buffered-io.c > @@ -60,6 +60,8 @@ iomap_page_create(struct inode *inode, struct page *page) > iop = kzalloc(struct_size(iop, uptodate, BITS_TO_LONGS(nr_blocks)), > GFP_NOFS | __GFP_NOFAIL); > spin_lock_init(&iop->uptodate_lock); > + if (PageUptodate(page)) > + bitmap_fill(iop->uptodate, nr_blocks); > attach_page_private(page, iop); > return iop; > } > @@ -494,10 +496,14 @@ iomap_invalidatepage(struct page *page, unsigned int offset, unsigned int len) > * If we are invalidating the entire page, clear the dirty state from it > * and release it to avoid unnecessary buildup of the LRU. > */ > - if (offset == 0 && len == PAGE_SIZE) { > + if (offset == 0 && len == thp_size(page)) { > WARN_ON_ONCE(PageWriteback(page)); > cancel_dirty_page(page); > iomap_page_release(page); > + } else if (PageTransHuge(page)) { > + /* Punching a hole in a THP requires releasing the iop */ > + WARN_ON_ONCE(!PageUptodate(page) && PageDirty(page)); > + iomap_page_release(page); > } > } > EXPORT_SYMBOL_GPL(iomap_invalidatepage); > @@ -1363,14 +1369,13 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, > struct writeback_control *wbc, struct inode *inode, > struct page *page, u64 end_offset) > { > - struct iomap_page *iop = to_iomap_page(page); > + struct iomap_page *iop = iomap_page_create(inode, page); > struct iomap_ioend *ioend, *next; > unsigned len = i_blocksize(inode); > u64 file_offset; /* file offset of page */ > int error = 0, count = 0, i; > LIST_HEAD(submit_list); > > - WARN_ON_ONCE(i_blocks_per_page(inode, page) > 1 && !iop); > WARN_ON_ONCE(iop && atomic_read(&iop->write_bytes_pending) != 0); > > /* > @@ -1415,7 +1420,6 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, > */ > if (wpc->ops->discard_page) > wpc->ops->discard_page(page); > - ClearPageUptodate(page); Er, I don't get it -- why do we now leave the page up to date after writeback fails? --D > unlock_page(page); > goto done; > } > -- > 2.28.0 >