Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933508AbaGVWvC (ORCPT ); Tue, 22 Jul 2014 18:51:02 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:44440 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932507AbaGVWWy (ORCPT ); Tue, 22 Jul 2014 18:22:54 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Lukas Czerner , Mike Snitzer , Kamal Mostafa Subject: [PATCH 3.8 079/116] dm thin: update discard_granularity to reflect the thin-pool blocksize Date: Tue, 22 Jul 2014 15:21:30 -0700 Message-Id: <1406067727-19683-80-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1406067727-19683-1-git-send-email-kamal@canonical.com> References: <1406067727-19683-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.8.13.27 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Lukas Czerner commit 09869de57ed2728ae3c619803932a86cb0e2c4f8 upstream. DM thinp already checks whether the discard_granularity of the data device is a factor of the thin-pool block size. But when using the dm-thin-pool's discard passdown support, DM thinp was not selecting the max of the underlying data device's discard_granularity and the thin-pool's block size. Update set_discard_limits() to set discard_granularity to the max of these values. This enables blkdev_issue_discard() to properly align the discards that are sent to the DM thin device on a full block boundary. As such each discard will now cover an entire DM thin-pool block and the block will be reclaimed. Reported-by: Zdenek Kabelac Signed-off-by: Lukas Czerner Signed-off-by: Mike Snitzer Signed-off-by: Kamal Mostafa --- drivers/md/dm-thin.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index ca954b1..3d183ca 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -2479,7 +2479,8 @@ static void set_discard_limits(struct pool_c *pt, struct queue_limits *limits) */ if (pt->adjusted_pf.discard_passdown) { data_limits = &bdev_get_queue(pt->data_dev->bdev)->limits; - limits->discard_granularity = data_limits->discard_granularity; + limits->discard_granularity = max(data_limits->discard_granularity, + pool->sectors_per_block << SECTOR_SHIFT); } else if (block_size_is_power_of_two(pool)) limits->discard_granularity = pool->sectors_per_block << SECTOR_SHIFT; else -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/