From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 60540339363; Sun, 2 Aug 2026 19:52:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785700348; cv=none; b=WTakxhwl+z7UmPp/ObJbpfHbpZcdVho8JOkel8PeeEa70d8rcq7kX58PXNo57KrOb99gIPJ/bVasKtGcM3R5/IpZ6yex7iPgz14e+QYUb8ll3JioOB4lp2VO0nQOxSHEKsiwQR8pZ5Ql3ARLSkWSJ8ndBMOtMr8a0mCulzugp4g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785700348; c=relaxed/simple; bh=Rqgvn/E7BhWafURAISqtwi+YnqhKX7fLHXfIH5DzC3w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=p6gYXrHatMqEOwteB0bXHtSz1goUC31QnYd0r+3N1VWXI1E7F0nd4+lS5ScGvFL1fCMq4YJP/R65xXOPLkDIf2hNRvM3ssip/vrbJ8Vaqc3UB7NuRPPC/Rkvy1UxkB4ZbiDPqwgAyMs7OfoniRweJ0o9VGn3yU/Sl8PG7SVMvIE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JbL08JSx; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="JbL08JSx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DFBC01F000E9; Sun, 2 Aug 2026 19:52:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785700347; bh=4PXxOgVQSzPnexE6Ra77DyXCOwfRDzIjcDTA1bHcSRE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=JbL08JSxH8dIlxNWSV7R9Iac/PYrDzFTUZGfv+Q6SVe4KO1bJuZ+dtoVnWG9XDlsG P28ZxkogpCkSy76bmU5dc23kGH/TrwP/Xi5y4HdSwMfkACfK+FNr77Aodw8nFOTLNp EihXvqwcgzrhR3Sn7gOAEvtZRcgJ60L1h9ZnvLxc1AHb5iWhewhQoVBKlDWCdLkChy xSFtD066tmEiaaY9Lp0iPXCindcCoT9Utn4Yre4x6hgQN0u7AtdeZyLgwLwirEpEUl R7g9vOGOBoonbe9rWtJOd9l6jPoYIn15/4MIoNCSAmmF3jL+YQ/oGM/894Ke+mgms4 zutsy6vJa/p5A== From: Yu Kuai To: Song Liu , Li Nan , Xiao Ni Cc: Yu Kuai , linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, Mykola Marzhan , Su Yue Subject: [PATCH v5 27/29] md/raid5: reject llbitmap reshape when md chunk shrinks Date: Mon, 3 Aug 2026 03:50:36 +0800 Message-ID: <20260802195038.164272-28-yukuai@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260802195038.164272-1-yukuai@kernel.org> References: <20260802195038.164272-1-yukuai@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Yu Kuai llbitmap reshape keeps one live bitmap and cannot safely make an existing bitmap bit cover a smaller data range. The llbitmap chunksize itself will not shrink when mddev->chunk_sectors stays the same or grows. However, shrinking mddev->chunk_sectors shrinks sectors_per_chunk used by raid5_bitmap_sector_map(). That can shrink the effective data range covered by each bit across the old and new RAID5 geometry. Reject that reshape while llbitmap is active. Tested-by: Mykola Marzhan Signed-off-by: Yu Kuai --- drivers/md/raid5.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 88bf5a9ce573..67d56c92c8a4 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -8580,6 +8580,9 @@ static int check_reshape(struct mddev *mddev) if (!check_stripe_cache(mddev)) return -ENOSPC; + if (mddev->bitmap_id == ID_LLBITMAP && + mddev->new_chunk_sectors < mddev->chunk_sectors) + return -EOPNOTSUPP; if (mddev->new_chunk_sectors > mddev->chunk_sectors || mddev->delta_disks > 0) if (resize_chunks(conf, -- 2.51.0