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 AE2C5364E9E for ; Fri, 14 Aug 2026 06:32:23 +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=1786689144; cv=none; b=GrtzIE82xCXe15Ln8JiygVPRIrdWUyrThKF9sDIWM2s9tn29YNhuL5OMyF3QeD1OEHW4DsUV6D1p22+2CHCjxxtLob1INlCWTgA1mEfhs9RJ2sniWpN/BSAgFXRVbrWdAmxvWCK3kBWItMP3Uhs9wWXG27SQNJN4FF1e7eaq48k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786689144; c=relaxed/simple; bh=5lUp4qDZh7JZ2NGrRmvIAyk8UdVvaQakAva2eOdGVXI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=H3tRV1cTpGVsrlk0q6OT5tpQqsw1+IMC/bj0Z1TvQvGfPtfkND4qKwarIr4YvvofCa1tKpK33djEdWa+5FGkZiYSLHCfePBDUBgG8iUl5CdckuMy7oC3HEv1FAqgQd+y3IdwGffoQ60esPrLslB1iIXIW17SuuikVEqUMdp5e3M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Q3ZDTLGg; 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="Q3ZDTLGg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B3161F00A3D; Fri, 14 Aug 2026 06:32:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786689143; bh=Tv0cqVWyc4imCWD84Gsi79JtI2iu5WZuJdwlcWK5EEo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Q3ZDTLGgGpBPSTt/2zQselcPyrbK96NJVPfxNTbF2hBjrYJ0jdza2StqhBUakAWQ7 t7F3P1A0RRGe6ji9HszBn/qu7vFW2WGuH/Wou4LUsFZTlCjnJH/Ayq6uyr6+e2SWQp 40ceCXNbX9/NnorHXRodXYGl5GyfWhrdqtW42sPmsxWlucimo1IwUb/msGt33S9Bv2 Y1zGgmZc9lO12gOVgpeW8Mpb7HyTwJ7HoeLSlvFUYfUu0qYcVrpQIi9/S/8TEkyF3O xcS3m23j78p7uqZFW7GuYKJj7LibRykVVmEPXpql+l2WkcmitdmRogJMintVefnBdb XejlCUyniKNiw== From: Damien Le Moal To: Jens Axboe , linux-block@vger.kernel.org Cc: Christoph Hellwig Subject: [PATCH v4 13/13] block: flag zoned disks with GENHD_FL_NO_PART Date: Fri, 14 Aug 2026 15:32:01 +0900 Message-ID: <20260814063201.1762743-14-dlemoal@kernel.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260814063201.1762743-1-dlemoal@kernel.org> References: <20260814063201.1762743-1-dlemoal@kernel.org> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Zoned block devices do not support partitions. However, the partition table is nevertheless still inspected, and any partition found ignored with a warning in add_partition(). While this is generally not a problem, and in fact beneficial to the user as it indicates an invalid use of a zoned block device, scanning for a partition table on the device may result in issuing read operations to offline zones (e.g. after a disk head is depopulated for disks that support head management operations). Since partitions are ignored anyway, completely disable partition scanning for zoned gendisks by setting the flag GENHD_FL_NO_PART in __add_disk(). The existing check in add_partition() is left as-is to ensure that we still get a warning if for whatever reason, despite GENHD_FL_NO_PART, we still endup trying to add partitions. Flagging zoned disks with GENHD_FL_NO_PART also has the benefit to expose through sysfs the ext_range attribute with the value of 1 instead of the default DISK_MAX_PARTS, thus correctly advertizing the fact that zoned disks do not support partitions. Signed-off-by: Damien Le Moal Reviewed-by: Bart Van Assche Reviewed-by: Hannes Reinecke --- block/genhd.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index e8ce0cabf392..34a64077ba02 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -447,6 +447,13 @@ static int __add_disk(struct device *parent, struct gendisk *disk, bdev_set_flag(disk->part0, BD_HAS_SUBMIT_BIO); } + /* + * We do not support partitions with zoned block devices, so do not try + * to scan the partitions table. + */ + if (blk_queue_is_zoned(disk->queue)) + disk->flags |= GENHD_FL_NO_PART; + /* * If the driver provides an explicit major number it also must provide * the number of minors numbers supported, and those will be used to -- 2.55.0