From patchwork Wed Mar 4 19:50:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roman Gushchin X-Patchwork-Id: 11420663 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 0E7EA92A for ; Wed, 4 Mar 2020 19:50:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D88D021739 for ; Wed, 4 Mar 2020 19:50:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="OD+9dxjA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387398AbgCDTuM (ORCPT ); Wed, 4 Mar 2020 14:50:12 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:19666 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728614AbgCDTuL (ORCPT ); Wed, 4 Mar 2020 14:50:11 -0500 Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 024Jk8K7024747 for ; Wed, 4 Mar 2020 11:50:10 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=facebook; bh=zBd+5qaL3qCpMGDjmFLdwfve7IIb8GrWrTDOOZQAm1o=; b=OD+9dxjAszOVJAKEAHqFl5ws+jBOYe2g195UCbw2bPSpTkzs6EmmQISeR1R92rT5YRyl LRU03bd53091itcJ1s3NTjuQSG/NaPN4CTZw4jlxmzmE5U3id0y5CDdLuBo+KCCpYWvM IfvBE0k8ksQXOUa4dQibIPrH1PuDyABTm/o= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 2yjggj0u82-7 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 04 Mar 2020 11:50:10 -0800 Received: from intmgw001.41.prn1.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::d) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1779.2; Wed, 4 Mar 2020 11:50:06 -0800 Received: by devvm4439.prn2.facebook.com (Postfix, from userid 111017) id 1C713FEBAC0A; Wed, 4 Mar 2020 11:50:03 -0800 (PST) Smtp-Origin-Hostprefix: devvm From: Roman Gushchin Smtp-Origin-Hostname: devvm4439.prn2.facebook.com To: Josef Bacik , Chris Mason , David Sterba CC: , , , Rik van Riel , Roman Gushchin Smtp-Origin-Cluster: prn2c23 Subject: [PATCH] btrfs: implement migratepage callback Date: Wed, 4 Mar 2020 11:50:02 -0800 Message-ID: <20200304195002.3854765-1-guro@fb.com> X-Mailer: git-send-email 2.17.1 X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-03-04_08:2020-03-04,2020-03-04 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxscore=0 phishscore=0 impostorscore=0 adultscore=0 spamscore=0 suspectscore=0 clxscore=1011 bulkscore=0 malwarescore=0 priorityscore=1501 mlxlogscore=756 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2003040129 X-FB-Internal: deliver Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Currently btrfs doesn't provide a migratepage callback. It means that fallback_migrate_page() is used to migrate btrfs pages. fallback_migrate_page() cannot move dirty pages, instead it tries to flush them (in sync mode) or just fails (in async mode). In the sync mode pages which are scheduled to be processed by btrfs_writepage_fixup_worker() can't be effectively flushed by the migration code, because there is no established way to wait for the completion of the delayed work. It all leads to page migration failures. To fix it the patch implements a btrs-specific migratepage callback, which is similar to iomap_migrate_page() used by some other fs, except it does take care of the PagePrivate2 flag which is used for data ordering purposes. Signed-off-by: Roman Gushchin Reviewed-by: Chris Mason --- fs/btrfs/inode.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 7735ce6127c3..f23230b3cbda 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include #include "misc.h" @@ -8323,6 +8324,37 @@ static int btrfs_releasepage(struct page *page, gfp_t gfp_flags) return __btrfs_releasepage(page, gfp_flags); } +static int btrfs_migratepage(struct address_space *mapping, + struct page *newpage, struct page *page, + enum migrate_mode mode) +{ + int ret; + + ret = migrate_page_move_mapping(mapping, newpage, page, 0); + if (ret != MIGRATEPAGE_SUCCESS) + return ret; + + if (page_has_private(page)) { + ClearPagePrivate(page); + get_page(newpage); + set_page_private(newpage, page_private(page)); + set_page_private(page, 0); + put_page(page); + SetPagePrivate(newpage); + } + + if (PagePrivate2(page)) { + ClearPagePrivate2(page); + SetPagePrivate2(newpage); + } + + if (mode != MIGRATE_SYNC_NO_COPY) + migrate_page_copy(newpage, page); + else + migrate_page_states(newpage, page); + return MIGRATEPAGE_SUCCESS; +} + static void btrfs_invalidatepage(struct page *page, unsigned int offset, unsigned int length) { @@ -10525,6 +10557,7 @@ static const struct address_space_operations btrfs_aops = { .direct_IO = btrfs_direct_IO, .invalidatepage = btrfs_invalidatepage, .releasepage = btrfs_releasepage, + .migratepage = btrfs_migratepage, .set_page_dirty = btrfs_set_page_dirty, .error_remove_page = generic_error_remove_page, .swap_activate = btrfs_swap_activate,