Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755450AbbGCOlt (ORCPT ); Fri, 3 Jul 2015 10:41:49 -0400 Received: from mga11.intel.com ([192.55.52.93]:57062 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755373AbbGCOk6 (ORCPT ); Fri, 3 Jul 2015 10:40:58 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.15,400,1432623600"; d="scan'208";a="518435778" From: Matthew Wilcox To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Alexander Viro Cc: Matthew Wilcox , willy@linux.intel.com Subject: [PATCH v2 6/6] dax: bdev_direct_access() may sleep Date: Fri, 3 Jul 2015 10:40:43 -0400 Message-Id: <1435934443-17090-7-git-send-email-matthew.r.wilcox@intel.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1435934443-17090-1-git-send-email-matthew.r.wilcox@intel.com> References: <1435934443-17090-1-git-send-email-matthew.r.wilcox@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1147 Lines: 36 The brd driver is the only in-tree driver that may sleep currently. After some discussion on linux-fsdevel, we decided that any driver may choose to sleep in its ->direct_access method. To ensure that all callers of bdev_direct_access() are prepared for this, add a call to might_sleep(). Signed-off-by: Matthew Wilcox --- fs/block_dev.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/block_dev.c b/fs/block_dev.c index 0bb2993..1982437 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -446,6 +446,12 @@ long bdev_direct_access(struct block_device *bdev, sector_t sector, long avail; const struct block_device_operations *ops = bdev->bd_disk->fops; + /* + * The device driver is allowed to sleep, in order to make the + * memory directly accessible. + */ + might_sleep(); + if (size < 0) return size; if (!ops->direct_access) -- 2.1.4 -- 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/