From nobody Wed Nov 27 13:02:01 2024 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 54BE11C4625; Thu, 10 Oct 2024 13:35:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728567347; cv=none; b=eoJnE8tKMWrNE8ZsjWYk7q89BQ5G4vSivL+GEsPmSzNdh7VUQHHph+ddITEHYrEuM0VlKbC6zD5Jk6kZdFfH4Dgg25Mau06kQhiiNkpKwW9kA1KXUWrCIWQupSXm3d+jY3cv5afcrpsxzr6NOi9tMbNab7wkxUEAkarDN/+zxT0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728567347; c=relaxed/simple; bh=stsrva27qYMVu8ViiEei3hO+iSfuJcFVSbZW4duvV7I=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=AlsAdP5oIFBAOMdCEww1iLLMHiZ225Eb05ciSdq/HXQdLZJ0DYQ0G1rVlJIq3aZRiCZheq/LJcBJeozhhs7DOcYyo6Q4+4lTkieMOjds8oI2zS7zpVRxArKS3p73Ha5ZoRdFzVhv7r0BPdymQJPBRCsdq4iwHZuLfgHej7EynNs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com; spf=none smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4XPW3J5QrYz4f3kw2; Thu, 10 Oct 2024 21:35:24 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 644171A06D7; Thu, 10 Oct 2024 21:35:42 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgCXysYc2AdnDRnZDg--.21356S8; Thu, 10 Oct 2024 21:35:42 +0800 (CST) From: Zhang Yi To: linux-ext4@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, tytso@mit.edu, adilger.kernel@dilger.ca, jack@suse.cz, ritesh.list@gmail.com, yi.zhang@huawei.com, yi.zhang@huaweicloud.com, chengzhihao1@huawei.com, yukuai3@huawei.com Subject: [PATCH v3 04/10] ext4: refactor ext4_punch_hole() Date: Thu, 10 Oct 2024 21:33:27 +0800 Message-Id: <20241010133333.146793-5-yi.zhang@huawei.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20241010133333.146793-1-yi.zhang@huawei.com> References: <20241010133333.146793-1-yi.zhang@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgCXysYc2AdnDRnZDg--.21356S8 X-Coremail-Antispam: 1UD129KBjvJXoW3GF48tFWrGF1fAF17GFWfKrg_yoW3GrW8p3 y3Ary5Kr48WFyq9F4Iqr4DXF1Ik3WDKrWUWryxGr1fX34qyw1IgFs0kF1Fgay5trZrZr4j vF45t347WryUuFJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUHab4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E 14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7 xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Y z7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lF7Iv64x0x7Aq67IIx4CEVc8vx2IErcIFxwACI4 02YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCF 04k20xvEw4C26cxK6c8Ij28IcwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14 v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkG c2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI 0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8 JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxUFPETDU UUU Sender: yi.zhang@huaweicloud.com X-CM-SenderInfo: d1lo6xhdqjqx5xdzvxpfor3voofrz/ Content-Type: text/plain; charset="utf-8" The current implementation of ext4_punch_hole() contains complex position calculations and stale error tags. To improve the code's clarity and maintainability, it is essential to clean up the code and improve its readability, this can be achieved by: a) simplifying and renaming variables; b) eliminating unnecessary position calculations; c) writing back all data in data=3Djournal mode, and drop page cache from the original offset to the end, rather than using aligned blocks, d) renaming the stale error tags. Signed-off-by: Zhang Yi --- fs/ext4/inode.c | 140 +++++++++++++++++++++--------------------------- 1 file changed, 62 insertions(+), 78 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 94b923afcd9c..1d128333bd06 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3955,13 +3955,14 @@ int ext4_punch_hole(struct file *file, loff_t offse= t, loff_t length) { struct inode *inode =3D file_inode(file); struct super_block *sb =3D inode->i_sb; - ext4_lblk_t first_block, stop_block; + ext4_lblk_t start_lblk, end_lblk; struct address_space *mapping =3D inode->i_mapping; - loff_t first_block_offset, last_block_offset, max_length; - struct ext4_sb_info *sbi =3D EXT4_SB(inode->i_sb); + loff_t max_end =3D EXT4_SB(sb)->s_bitmap_maxbytes - sb->s_blocksize; + loff_t end =3D offset + length; + unsigned long blocksize =3D i_blocksize(inode); handle_t *handle; unsigned int credits; - int ret =3D 0, ret2 =3D 0; + int ret =3D 0; =20 trace_ext4_punch_hole(inode, offset, length, 0); =20 @@ -3969,36 +3970,27 @@ int ext4_punch_hole(struct file *file, loff_t offse= t, loff_t length) =20 /* No need to punch hole beyond i_size */ if (offset >=3D inode->i_size) - goto out_mutex; + goto out; =20 /* - * If the hole extends beyond i_size, set the hole - * to end after the page that contains i_size + * If the hole extends beyond i_size, set the hole to end after + * the page that contains i_size, and also make sure that the hole + * within one block before last range. */ - if (offset + length > inode->i_size) { - length =3D inode->i_size + - PAGE_SIZE - (inode->i_size & (PAGE_SIZE - 1)) - - offset; - } + if (end > inode->i_size) + end =3D round_up(inode->i_size, PAGE_SIZE); + if (end > max_end) + end =3D max_end; + length =3D end - offset; =20 /* - * For punch hole the length + offset needs to be within one block - * before last range. Adjust the length if it goes beyond that limit. + * Attach jinode to inode for jbd2 if we do any zeroing of partial + * block. */ - max_length =3D sbi->s_bitmap_maxbytes - inode->i_sb->s_blocksize; - if (offset + length > max_length) - length =3D max_length - offset; - - if (offset & (sb->s_blocksize - 1) || - (offset + length) & (sb->s_blocksize - 1)) { - /* - * Attach jinode to inode for jbd2 if we do any zeroing of - * partial block - */ + if (offset & (blocksize - 1) || end & (blocksize - 1)) { ret =3D ext4_inode_attach_jinode(inode); if (ret < 0) - goto out_mutex; - + goto out; } =20 /* Wait all existing dio workers, newcomers will block on i_rwsem */ @@ -4006,7 +3998,7 @@ int ext4_punch_hole(struct file *file, loff_t offset,= loff_t length) =20 ret =3D file_modified(file); if (ret) - goto out_mutex; + goto out; =20 /* * Prevent page faults from reinstantiating pages we have released from @@ -4016,34 +4008,24 @@ int ext4_punch_hole(struct file *file, loff_t offse= t, loff_t length) =20 ret =3D ext4_break_layouts(inode); if (ret) - goto out_dio; - - first_block_offset =3D round_up(offset, sb->s_blocksize); - last_block_offset =3D round_down((offset + length), sb->s_blocksize) - 1; + goto out_invalidate_lock; =20 - /* Now release the pages and zero block aligned part of pages*/ - if (last_block_offset > first_block_offset) { + /* + * For journalled data we need to write (and checkpoint) pages + * before discarding page cache to avoid inconsitent data on + * disk in case of crash before punching trans is committed. + */ + if (ext4_should_journal_data(inode)) { + ret =3D filemap_write_and_wait_range(mapping, offset, end - 1); + } else { ret =3D ext4_update_disksize_before_punch(inode, offset, length); - if (ret) - goto out_dio; - - /* - * For journalled data we need to write (and checkpoint) pages - * before discarding page cache to avoid inconsitent data on - * disk in case of crash before punching trans is committed. - */ - if (ext4_should_journal_data(inode)) { - ret =3D filemap_write_and_wait_range(mapping, - first_block_offset, last_block_offset); - if (ret) - goto out_dio; - } - - ext4_truncate_folios_range(inode, first_block_offset, - last_block_offset + 1); - truncate_pagecache_range(inode, first_block_offset, - last_block_offset); + ext4_truncate_folios_range(inode, offset, end); } + if (ret) + goto out_invalidate_lock; + + /* Now release the pages and zero block aligned part of pages*/ + truncate_pagecache_range(inode, offset, end - 1); =20 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) credits =3D ext4_writepage_trans_blocks(inode); @@ -4053,52 +4035,54 @@ int ext4_punch_hole(struct file *file, loff_t offse= t, loff_t length) if (IS_ERR(handle)) { ret =3D PTR_ERR(handle); ext4_std_error(sb, ret); - goto out_dio; + goto out_invalidate_lock; } =20 - ret =3D ext4_zero_partial_blocks(handle, inode, offset, - length); + ret =3D ext4_zero_partial_blocks(handle, inode, offset, length); if (ret) - goto out_stop; - - first_block =3D (offset + sb->s_blocksize - 1) >> - EXT4_BLOCK_SIZE_BITS(sb); - stop_block =3D (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb); + goto out_handle; =20 /* If there are blocks to remove, do it */ - if (stop_block > first_block) { - ext4_lblk_t hole_len =3D stop_block - first_block; + start_lblk =3D round_up(offset, blocksize) >> inode->i_blkbits; + end_lblk =3D end >> inode->i_blkbits; + + if (end_lblk > start_lblk) { + ext4_lblk_t hole_len =3D end_lblk - start_lblk; =20 down_write(&EXT4_I(inode)->i_data_sem); ext4_discard_preallocations(inode); =20 - ext4_es_remove_extent(inode, first_block, hole_len); + ext4_es_remove_extent(inode, start_lblk, hole_len); =20 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) - ret =3D ext4_ext_remove_space(inode, first_block, - stop_block - 1); + ret =3D ext4_ext_remove_space(inode, start_lblk, + end_lblk - 1); else - ret =3D ext4_ind_remove_space(handle, inode, first_block, - stop_block); + ret =3D ext4_ind_remove_space(handle, inode, start_lblk, + end_lblk); + if (ret) { + up_write(&EXT4_I(inode)->i_data_sem); + goto out_handle; + } =20 - ext4_es_insert_extent(inode, first_block, hole_len, ~0, + ext4_es_insert_extent(inode, start_lblk, hole_len, ~0, EXTENT_STATUS_HOLE, 0); up_write(&EXT4_I(inode)->i_data_sem); } - ext4_fc_track_range(handle, inode, first_block, stop_block); + ext4_fc_track_range(handle, inode, start_lblk, end_lblk); + + ret =3D ext4_mark_inode_dirty(handle, inode); + if (unlikely(ret)) + goto out_handle; + + ext4_update_inode_fsync_trans(handle, inode, 1); if (IS_SYNC(inode)) ext4_handle_sync(handle); - - ret2 =3D ext4_mark_inode_dirty(handle, inode); - if (unlikely(ret2)) - ret =3D ret2; - if (ret >=3D 0) - ext4_update_inode_fsync_trans(handle, inode, 1); -out_stop: +out_handle: ext4_journal_stop(handle); -out_dio: +out_invalidate_lock: filemap_invalidate_unlock(mapping); -out_mutex: +out: inode_unlock(inode); return ret; } --=20 2.39.2