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=-6.7 required=3.0 tests=FORGED_MUA_MOZILLA, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 BF029CA9EB9 for ; Tue, 29 Oct 2019 05:47:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8458A20659 for ; Tue, 29 Oct 2019 05:47:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730384AbfJ2FrI (ORCPT ); Tue, 29 Oct 2019 01:47:08 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:52298 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727227AbfJ2FrI (ORCPT ); Tue, 29 Oct 2019 01:47:08 -0400 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x9T4uEte138888 for ; Tue, 29 Oct 2019 01:47:06 -0400 Received: from e06smtp02.uk.ibm.com (e06smtp02.uk.ibm.com [195.75.94.98]) by mx0a-001b2d01.pphosted.com with ESMTP id 2vxbdsxrb7-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 29 Oct 2019 01:47:06 -0400 Received: from localhost by e06smtp02.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 29 Oct 2019 05:47:02 -0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x9T5l1rj14024916 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 29 Oct 2019 05:47:01 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 17314A4065; Tue, 29 Oct 2019 05:47:01 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C6426A4060; Tue, 29 Oct 2019 05:46:58 +0000 (GMT) Received: from [9.199.158.60] (unknown [9.199.158.60]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 29 Oct 2019 05:46:58 +0000 (GMT) Subject: Re: [PATCH v6 08/11] ext4: move inode extension/truncate code out from ->iomap_end() callback To: Matthew Bobrowski , tytso@mit.edu, jack@suse.cz, adilger.kernel@dilger.ca Cc: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, hch@infradead.org, david@fromorbit.com, darrick.wong@oracle.com References: From: Ritesh Harjani Date: Tue, 29 Oct 2019 11:16:57 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19102905-0008-0000-0000-00000328A20D X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19102905-0009-0000-0000-00004A47E281 Message-Id: <20191029054658.C6426A4060@b06wcsmtp001.portsmouth.uk.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-10-29_02:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=985 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910290044 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On 10/28/19 4:22 PM, Matthew Bobrowski wrote: > In preparation for implementing the iomap direct I/O modifications, > the inode extension/truncate code needs to be moved out from the > ext4_iomap_end() callback. For direct I/O, if the current code > remained, it would behave incorrrectly. Updating the inode size prior > to converting unwritten extents would potentially allow a racing > direct I/O read to find unwritten extents before being converted > correctly. > > The inode extension/truncate code now resides within a new helper > ext4_handle_inode_extension(). This function has been designed so that > it can accommodate for both DAX and direct I/O extension/truncate > operations. > > Signed-off-by: Matthew Bobrowski > Reviewed-by: Jan Kara Thanks for the patch. Looks good to me. You may add: Reviewed-by: Ritesh Harjani > --- > fs/ext4/file.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++- > fs/ext4/inode.c | 48 +------------------------- > 2 files changed, 89 insertions(+), 48 deletions(-) > > diff --git a/fs/ext4/file.c b/fs/ext4/file.c > index 440f4c6ba4ee..ec54fec96a81 100644 > --- a/fs/ext4/file.c > +++ b/fs/ext4/file.c > @@ -33,6 +33,7 @@ > #include "ext4_jbd2.h" > #include "xattr.h" > #include "acl.h" > +#include "truncate.h" > > static bool ext4_dio_supported(struct inode *inode) > { > @@ -234,12 +235,95 @@ static ssize_t ext4_write_checks(struct kiocb *iocb, struct iov_iter *from) > return iov_iter_count(from); > } > > +static ssize_t ext4_handle_inode_extension(struct inode *inode, loff_t offset, > + ssize_t written, size_t count) > +{ > + handle_t *handle; > + bool truncate = false; > + u8 blkbits = inode->i_blkbits; > + ext4_lblk_t written_blk, end_blk; > + > + /* > + * Note that EXT4_I(inode)->i_disksize can get extended up to > + * inode->i_size while the I/O was running due to writeback of delalloc > + * blocks. But, the code in ext4_iomap_alloc() is careful to use > + * zeroed/unwritten extents if this is possible; thus we won't leave > + * uninitialized blocks in a file even if we didn't succeed in writing > + * as much as we intended. > + */ > + WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize); > + if (offset + count <= EXT4_I(inode)->i_disksize) { > + /* > + * We need to ensure that the inode is removed from the orphan > + * list if it has been added prematurely, due to writeback of > + * delalloc blocks. > + */ > + if (!list_empty(&EXT4_I(inode)->i_orphan) && inode->i_nlink) { > + handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); > + > + if (IS_ERR(handle)) { > + ext4_orphan_del(NULL, inode); > + return PTR_ERR(handle); > + } > + > + ext4_orphan_del(handle, inode); > + ext4_journal_stop(handle); > + } > + > + return written; > + } > + > + if (written < 0) > + goto truncate; > + > + handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); > + if (IS_ERR(handle)) { > + written = PTR_ERR(handle); > + goto truncate; > + } > + > + if (ext4_update_inode_size(inode, offset + written)) > + ext4_mark_inode_dirty(handle, inode); > + > + /* > + * We may need to truncate allocated but not written blocks beyond EOF. > + */ > + written_blk = ALIGN(offset + written, 1 << blkbits); > + end_blk = ALIGN(offset + count, 1 << blkbits); > + if (written_blk < end_blk && ext4_can_truncate(inode)) > + truncate = true; > + > + /* > + * Remove the inode from the orphan list if it has been extended and > + * everything went OK. > + */ > + if (!truncate && inode->i_nlink) > + ext4_orphan_del(handle, inode); > + ext4_journal_stop(handle); > + > + if (truncate) { > +truncate: > + ext4_truncate_failed_write(inode); > + /* > + * If the truncate operation failed early, then the inode may > + * still be on the orphan list. In that case, we need to try > + * remove the inode from the in-memory linked list. > + */ > + if (inode->i_nlink) > + ext4_orphan_del(NULL, inode); > + } > + > + return written; > +} > + > #ifdef CONFIG_FS_DAX > static ssize_t > ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from) > { > - struct inode *inode = file_inode(iocb->ki_filp); > ssize_t ret; > + size_t count; > + loff_t offset; > + struct inode *inode = file_inode(iocb->ki_filp); > > if (!inode_trylock(inode)) { > if (iocb->ki_flags & IOCB_NOWAIT) > @@ -256,7 +340,10 @@ ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from) > if (ret) > goto out; > > + offset = iocb->ki_pos; > + count = iov_iter_count(from); > ret = dax_iomap_rw(iocb, from, &ext4_iomap_ops); > + ret = ext4_handle_inode_extension(inode, offset, ret, count); > out: > inode_unlock(inode); > if (ret > 0) > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index e44b3b1dbbc4..7c21028760ee 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -3543,53 +3543,7 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > static int ext4_iomap_end(struct inode *inode, loff_t offset, loff_t length, > ssize_t written, unsigned flags, struct iomap *iomap) > { > - int ret = 0; > - handle_t *handle; > - int blkbits = inode->i_blkbits; > - bool truncate = false; > - > - if (!(flags & IOMAP_WRITE) || (flags & IOMAP_FAULT)) > - return 0; > - > - handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); > - if (IS_ERR(handle)) { > - ret = PTR_ERR(handle); > - goto orphan_del; > - } > - if (ext4_update_inode_size(inode, offset + written)) > - ext4_mark_inode_dirty(handle, inode); > - /* > - * We may need to truncate allocated but not written blocks beyond EOF. > - */ > - if (iomap->offset + iomap->length > > - ALIGN(inode->i_size, 1 << blkbits)) { > - ext4_lblk_t written_blk, end_blk; > - > - written_blk = (offset + written) >> blkbits; > - end_blk = (offset + length) >> blkbits; > - if (written_blk < end_blk && ext4_can_truncate(inode)) > - truncate = true; > - } > - /* > - * Remove inode from orphan list if we were extending a inode and > - * everything went fine. > - */ > - if (!truncate && inode->i_nlink && > - !list_empty(&EXT4_I(inode)->i_orphan)) > - ext4_orphan_del(handle, inode); > - ext4_journal_stop(handle); > - if (truncate) { > - ext4_truncate_failed_write(inode); > -orphan_del: > - /* > - * If truncate failed early the inode might still be on the > - * orphan list; we need to make sure the inode is removed from > - * the orphan list in that case. > - */ > - if (inode->i_nlink) > - ext4_orphan_del(NULL, inode); > - } > - return ret; > + return 0; > } > > const struct iomap_ops ext4_iomap_ops = { >