From mboxrd@z Thu Jan 1 00:00:00 1970 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 4580ED531; Tue, 13 Aug 2024 02:14:45 +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=1723515289; cv=none; b=UTqFHQ7D8yK4GM14CoU1x84RMUq2zvZDMh4DQ1/tSqqAEfs4m68SX3vC6ScpycFXblPsinlzaKDaj2ON8FvSBSNTlCCcP28DWrtzEC+C2DEytSWBkarfsW/Cm1nZAXe19wEhKDy4pdy+UZu4mv01mR6hDFjil5qkMDsl3DnT3UE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723515289; c=relaxed/simple; bh=vvhvWKIh2t4mtzuVwGeHfsr+W2bjpTI1kncVkcWG15g=; h=Subject:To:Cc:References:From:Message-ID:Date:MIME-Version: In-Reply-To:Content-Type; b=OwfhQ4boemyuW//CA1MQ1JYC2/zo2zSu9N+khH7Ya8WQJKdmJRSVv7qEVyHt9373XwWbYR/5BLrYXgAxfP86GuyMmeLDUUKaHWLIb0b9eiRuKv1JQ5zR699/qv1zJ4irkH9F5nb4cSRDzcbF6kAANm/91UZmyClPX4OuiLrdMf4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4WjZhM6kHwz4f3kvY; Tue, 13 Aug 2024 10:14:27 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 91AA81A058E; Tue, 13 Aug 2024 10:14:42 +0800 (CST) Received: from [10.174.179.80] (unknown [10.174.179.80]) by APP4 (Coremail) with SMTP id gCh0CgAHL4WQwbpmVecoBg--.63080S3; Tue, 13 Aug 2024 10:14:42 +0800 (CST) Subject: Re: [PATCH v2 1/6] iomap: correct the range of a partial dirty clear To: "Darrick J. Wong" Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, hch@infradead.org, brauner@kernel.org, david@fromorbit.com, jack@suse.cz, willy@infradead.org, yi.zhang@huawei.com, chengzhihao1@huawei.com, yukuai3@huawei.com References: <20240812121159.3775074-1-yi.zhang@huaweicloud.com> <20240812121159.3775074-2-yi.zhang@huaweicloud.com> <20240812163339.GD6043@frogsfrogsfrogs> From: Zhang Yi Message-ID: Date: Tue, 13 Aug 2024 10:14:40 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20240812163339.GD6043@frogsfrogsfrogs> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-CM-TRANSID:gCh0CgAHL4WQwbpmVecoBg--.63080S3 X-Coremail-Antispam: 1UD129KBjvJXoW7ury8Jr13Kw1UWrW5Xw1UWrg_yoW8ur1rpr s3KF4UKrWDXry29r1xXFyrXFn5tanrWF48JrW7WryrWan0qr1fKr109ay3uF92gr4xAF10 vF1agrWxCrWqyaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9Ib4IE77IF4wAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4 vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7Cj xVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x 0267AKxVW0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG 6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFV Cjc4AY6r1j6r4UM4x0Y48IcVAKI48JM4IIrI8v6xkF7I0E8cxan2IY04v7Mxk0xIA0c2IE e2xFo4CEbIxvr21lc7CjxVAaw2AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4I kC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWU WwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr 0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWU JVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJb IYCTnIWIevJa73UjIFyTuYvjxUF1v3UUUUU X-CM-SenderInfo: d1lo6xhdqjqx5xdzvxpfor3voofrz/ On 2024/8/13 0:33, Darrick J. Wong wrote: > On Mon, Aug 12, 2024 at 08:11:54PM +0800, Zhang Yi wrote: >> From: Zhang Yi >> >> The block range calculation in ifs_clear_range_dirty() is incorrect when >> partial clear a range in a folio. We can't clear the dirty bit of the >> first block or the last block if the start or end offset is blocksize >> unaligned, this has not yet caused any issue since we always clear a >> whole folio in iomap_writepage_map()->iomap_clear_range_dirty(). Fix >> this by round up the first block and round down the last block and >> correct the calculation of nr_blks. >> >> Signed-off-by: Zhang Yi >> --- >> fs/iomap/buffered-io.c | 9 ++++++--- >> 1 file changed, 6 insertions(+), 3 deletions(-) >> >> diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c >> index f420c53d86ac..4da453394aaf 100644 >> --- a/fs/iomap/buffered-io.c >> +++ b/fs/iomap/buffered-io.c >> @@ -138,11 +138,14 @@ static void ifs_clear_range_dirty(struct folio *folio, >> { >> struct inode *inode = folio->mapping->host; >> unsigned int blks_per_folio = i_blocks_per_folio(inode, folio); >> - unsigned int first_blk = (off >> inode->i_blkbits); >> - unsigned int last_blk = (off + len - 1) >> inode->i_blkbits; >> - unsigned int nr_blks = last_blk - first_blk + 1; >> + unsigned int first_blk = DIV_ROUND_UP(off, i_blocksize(inode)); > > Is there a round up macro that doesn't involve integer division? > Sorry, I don't find a common macro now, if we want to avoid integer division, how about open code here? first_blk = round_up(off, i_blocksize(inode)) >> inode->i_blkbits; Thanks, Yi. > >> + unsigned int last_blk = (off + len) >> inode->i_blkbits; >> + unsigned int nr_blks = last_blk - first_blk; >> unsigned long flags; >> >> + if (!nr_blks) >> + return; >> + >> spin_lock_irqsave(&ifs->state_lock, flags); >> bitmap_clear(ifs->state, first_blk + blks_per_folio, nr_blks); >> spin_unlock_irqrestore(&ifs->state_lock, flags); >> -- >> 2.39.2 >> >>