From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:58628 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753897AbcHRJ6o (ORCPT ); Thu, 18 Aug 2016 05:58:44 -0400 Subject: Patch "Btrfs: fix delalloc accounting after copy_from_user faults" has been added to the 4.7-stable tree To: clm@fb.com, gregkh@linuxfoundation.org Cc: , From: Date: Thu, 18 Aug 2016 11:58:52 +0200 Message-ID: <147151433216024@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 Btrfs: fix delalloc accounting after copy_from_user faults to the 4.7-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: btrfs-fix-delalloc-accounting-after-copy_from_user-faults.patch and it can be found in the queue-4.7 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 8b8b08cbfb9021af4b54b4175fc4c51d655aac8c Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 19 Jul 2016 05:52:36 -0700 Subject: Btrfs: fix delalloc accounting after copy_from_user faults From: Chris Mason commit 8b8b08cbfb9021af4b54b4175fc4c51d655aac8c upstream. Commit 56244ef151c3cd11 was almost but not quite enough to fix the reservation math after btrfs_copy_from_user returned partial copies. Some users are still seeing warnings in btrfs_destroy_inode, and with a long enough test run I'm able to trigger them as well. This patch fixes the accounting math again, bringing it much closer to the way it was before the sectorsize conversion Chandan did. The problem is accounting for the offset into the page/sector when we do a partial copy. This one just uses the dirty_sectors variable which should already be updated properly. Signed-off-by: Chris Mason Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/file.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1629,13 +1629,11 @@ again: * managed to copy. */ if (num_sectors > dirty_sectors) { - /* - * we round down because we don't want to count - * any partial blocks actually sent through the - * IO machines - */ - release_bytes = round_down(release_bytes - copied, - root->sectorsize); + + /* release everything except the sectors we dirtied */ + release_bytes -= dirty_sectors << + root->fs_info->sb->s_blocksize_bits; + if (copied > 0) { spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->outstanding_extents++; Patches currently in stable-queue which might be from clm@fb.com are queue-4.7/btrfs-fix-delalloc-accounting-after-copy_from_user-faults.patch