From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755385AbdKGALa (ORCPT ); Mon, 6 Nov 2017 19:11:30 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53550 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754591AbdKGAL1 (ORCPT ); Mon, 6 Nov 2017 19:11:27 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Pierguido Lambri" , "Steve French" , "Sachin Prabhu" Date: Mon, 06 Nov 2017 23:03:02 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 133/294] cifs: Fix df output for users with quota limits In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Sachin Prabhu commit 42bec214d8bd432be6d32a1acb0a9079ecd4d142 upstream. The df for a SMB2 share triggers a GetInfo call for FS_FULL_SIZE_INFORMATION. The values returned are used to populate struct statfs. The problem is that none of the information returned by the call contains the total blocks available on the filesystem. Instead we use the blocks available to the user ie. quota limitation when filling out statfs.f_blocks. The information returned does contain Actual free units on the filesystem and is used to populate statfs.f_bfree. For users with quota enabled, it can lead to situations where the total free space reported is more than the total blocks on the system ending up with df reports like the following # df -h /mnt/a Filesystem Size Used Avail Use% Mounted on //192.168.22.10/a 2.5G -2.3G 2.5G - /mnt/a To fix this problem, we instead populate both statfs.f_bfree with the same value as statfs.f_bavail ie. CallerAvailableAllocationUnits. This is similar to what is done already in the code for cifs and df now reports the quota information for the user used to mount the share. # df --si /mnt/a Filesystem Size Used Avail Use% Mounted on //192.168.22.10/a 2.7G 101M 2.6G 4% /mnt/a Signed-off-by: Sachin Prabhu Signed-off-by: Pierguido Lambri Signed-off-by: Steve French Signed-off-by: Ben Hutchings --- fs/cifs/smb2pdu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -2486,8 +2486,8 @@ copy_fs_info_to_kstatfs(struct smb2_fs_f kst->f_bsize = le32_to_cpu(pfs_inf->BytesPerSector) * le32_to_cpu(pfs_inf->SectorsPerAllocationUnit); kst->f_blocks = le64_to_cpu(pfs_inf->TotalAllocationUnits); - kst->f_bfree = le64_to_cpu(pfs_inf->ActualAvailableAllocationUnits); - kst->f_bavail = le64_to_cpu(pfs_inf->CallerAvailableAllocationUnits); + kst->f_bfree = kst->f_bavail = + le64_to_cpu(pfs_inf->CallerAvailableAllocationUnits); return; }