From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:40497 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753100AbbJMVtv (ORCPT ); Tue, 13 Oct 2015 17:49:51 -0400 Subject: Patch "dax: fix O_DIRECT I/O to the last block of a blockdev" has been added to the 4.2-stable tree To: jmoyer@redhat.com, dan.j.williams@intel.com, gregkh@linuxfoundation.org, linda.knippers@hp.com Cc: , From: Date: Tue, 13 Oct 2015 14:49:48 -0700 Message-ID: <1444772988236227@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled dax: fix O_DIRECT I/O to the last block of a blockdev to the 4.2-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dax-fix-o_direct-i-o-to-the-last-block-of-a-blockdev.patch and it can be found in the queue-4.2 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From e94f5a2285fc94202a9efb2c687481f29b64132c Mon Sep 17 00:00:00 2001 From: Jeff Moyer Date: Fri, 14 Aug 2015 16:15:31 -0400 Subject: dax: fix O_DIRECT I/O to the last block of a blockdev From: Jeff Moyer commit e94f5a2285fc94202a9efb2c687481f29b64132c upstream. commit bbab37ddc20b (block: Add support for DAX reads/writes to block devices) caused a regression in mkfs.xfs. That utility sets the block size of the device to the logical block size using the BLKBSZSET ioctl, and then issues a single sector read from the last sector of the device. This results in the dax_io code trying to do a page-sized read from 512 bytes from the end of the device. The result is -ERANGE being returned to userspace. The fix is to align the block to the page size before calling get_block. Thanks to willy for simplifying my original patch. Signed-off-by: Jeff Moyer Tested-by: Linda Knippers Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- fs/dax.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/dax.c +++ b/fs/dax.c @@ -116,7 +116,8 @@ static ssize_t dax_io(struct inode *inod unsigned len; if (pos == max) { unsigned blkbits = inode->i_blkbits; - sector_t block = pos >> blkbits; + long page = pos >> PAGE_SHIFT; + sector_t block = page << (PAGE_SHIFT - blkbits); unsigned first = pos - (block << blkbits); long size; Patches currently in stable-queue which might be from jmoyer@redhat.com are queue-4.2/blockdev-don-t-set-s_dax-for-misaligned-partitions.patch queue-4.2/dax-fix-o_direct-i-o-to-the-last-block-of-a-blockdev.patch