From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754034Ab2GIOOa (ORCPT ); Mon, 9 Jul 2012 10:14:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:4175 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753682Ab2GIOO3 (ORCPT ); Mon, 9 Jul 2012 10:14:29 -0400 Date: Mon, 9 Jul 2012 10:14:16 -0400 From: Mike Snitzer To: "Chauhan, Vijay" Cc: "dm-devel@redhat.com" , "Moger, Babu" , "Martin K. Petersen" , "Stankey, Robert" , axboe@kernel.dk, linux-kernel@vger.kernel.org Subject: [PATCH] block: do not artificially constrain max_sectors for stacking drivers Message-ID: <20120709141416.GB30633@redhat.com> References: <20120709130052.GC30048@redhat.com> <20120709131611.GD30048@redhat.com> <20120709134041.GA30633@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120709134041.GA30633@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org blk_set_stacking_limits is intended to allow stacking drivers to build up the limits of the stacked device based on the underlying devices' limits. But in the case of 'max_sectors' the default of BLK_DEF_MAX_SECTORS (1024) doesn't allow the stacking driver to inherit a max_sectors larger than 1024. It is now clear that this artificial limit is getting in the way so change blk_set_stacking_limits's max_sectors to UINT_MAX (which allows stacking drivers like dm-multipath to inherit 'max_sectors' from the underlying paths). Reported-by: Vijay Chauhan Signed-off-by: Mike Snitzer Cc: Martin K. Petersen --- block/blk-settings.c | 3 +-- 1 files changed, 1 insertions(+), 2 deletions(-) diff --git a/block/blk-settings.c b/block/blk-settings.c index d3234fc..565a678 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -143,8 +143,7 @@ void blk_set_stacking_limits(struct queue_limits *lim) lim->discard_zeroes_data = 1; lim->max_segments = USHRT_MAX; lim->max_hw_sectors = UINT_MAX; - - lim->max_sectors = BLK_DEF_MAX_SECTORS; + lim->max_sectors = UINT_MAX; } EXPORT_SYMBOL(blk_set_stacking_limits);