From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Snitzer Subject: [RESEND PATCH] block: do not artificially constrain max_sectors for stacking drivers Date: Tue, 31 Jul 2012 20:39:13 -0400 Message-ID: <1343781553-17089-1-git-send-email-snitzer@redhat.com> References: <20120710191859.GB3831@redhat.com> Return-path: In-Reply-To: <20120710191859.GB3831@redhat.com> Sender: linux-kernel-owner@vger.kernel.org To: axboe@kernel.dk Cc: linux-kernel@vger.kernel.org, dm-devel@redhat.com, vijay.chauhan@netapp.com List-Id: dm-devel.ids 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 defaulting 'max_sectors' to BLK_DEF_MAX_SECTORS (1024) doesn't allow the stacking driver to inherit a max_sectors larger than 1024 -- due to blk_stack_limits' use of min_not_zero. 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 Tested-by: Vijay Chauhan Signed-off-by: Mike Snitzer --- 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); -- 1.7.4.4