From patchwork Thu Feb 27 21:33:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 11410283 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 00B7C17E0 for ; Thu, 27 Feb 2020 21:34:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CB9E024677 for ; Thu, 27 Feb 2020 21:34:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="lT5SdL84" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729984AbgB0VeA (ORCPT ); Thu, 27 Feb 2020 16:34:00 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:43810 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726460AbgB0VeA (ORCPT ); Thu, 27 Feb 2020 16:34:00 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 01RLMpsU030108; Thu, 27 Feb 2020 21:33:59 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : from : to : cc : date : message-id : in-reply-to : references : mime-version : content-type : content-transfer-encoding; s=corp-2020-01-29; bh=SK3ORLcKLc32g22nLM5e6u2awazlkXAzyNrheC/M/BA=; b=lT5SdL84B4X3pWTeDR0nkPy5ugvzX8hus7R1OMp/2Bm/Crus2nfbx5DOs7IezcH/6IwS tR4fTgOPDF+iSnaBoY/c6d4P8Zxi79tNQFR6tQj6fPEkfMNyawQkHimbRgbnwYWG3yDL +MiHLGI1/TLX/rEaOi67VKHg4yy2RGVfZjQChzjkzHBMYFsRvelgVUF7DaUdCwMCUQew wz+Fb8NpAnu2n1MZtEUTQc+1aJ5NB903eA/f+XI83aU4UjKjhHz+BBw4HZAv+HfmzDHE r/lTWG6tFZlmooZawAY3GAttgzNVqj/RGhpchG5H9ry9N3SeI1vPL3rgZFLgmfzHhD4L pg== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by userp2120.oracle.com with ESMTP id 2ydct3ds5g-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 27 Feb 2020 21:33:59 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 01RLIIK4052026; Thu, 27 Feb 2020 21:33:58 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3030.oracle.com with ESMTP id 2ydcs6bw07-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 27 Feb 2020 21:33:58 +0000 Received: from abhmp0020.oracle.com (abhmp0020.oracle.com [141.146.116.26]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 01RLXvef008864; Thu, 27 Feb 2020 21:33:58 GMT Received: from localhost (/10.145.179.117) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 27 Feb 2020 13:33:57 -0800 Subject: [PATCH 3/3] ext4: allow online filesystem uuid queries From: "Darrick J. Wong" To: darrick.wong@oracle.com Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org Date: Thu, 27 Feb 2020 13:33:54 -0800 Message-ID: <158283923456.904118.14244827054399587376.stgit@magnolia> In-Reply-To: <158283921562.904118.13877489081184026686.stgit@magnolia> References: <158283921562.904118.13877489081184026686.stgit@magnolia> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9544 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 bulkscore=0 malwarescore=0 mlxlogscore=999 mlxscore=0 phishscore=0 suspectscore=1 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002270142 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9544 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 lowpriorityscore=0 bulkscore=0 impostorscore=0 spamscore=0 priorityscore=1501 malwarescore=0 adultscore=0 phishscore=0 mlxlogscore=999 mlxscore=0 suspectscore=1 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002270142 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Darrick J. Wong Wire up the new ioctls to get and set the ext4 filesystem uuid. Signed-off-by: Darrick J. Wong --- fs/ext4/ioctl.c | 132 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 132 insertions(+) diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index a0ec750018dd..c8d556c93cc7 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -813,6 +813,132 @@ static int ext4_ioctl_get_es_cache(struct file *filp, unsigned long arg) return error; } +static int ext4_ioc_getfsuuid(struct super_block *sb, + struct ioc_fsuuid __user *user_fu) +{ + struct ioc_fsuuid fu; + struct ext4_super_block *es = EXT4_SB(sb)->s_es; + + BUILD_BUG_ON(sizeof(es->s_uuid) != sizeof(uuid_t)); + + if (copy_from_user(&fu, user_fu, sizeof(fu))) + return -EFAULT; + + if (fu.fu_reserved || fu.fu_reserved1 || fu.fu_flags) + return -EINVAL; + + if (fu.fu_length == 0) { + fu.fu_length = sizeof(es->s_uuid); + goto out; + } + + if (fu.fu_length < sizeof(es->s_uuid)) + return -EINVAL; + + if (copy_to_user(user_fu + 1, es->s_uuid, sizeof(es->s_uuid))) + return -EFAULT; + fu.fu_length = sizeof(es->s_uuid); + +out: + if (copy_to_user(user_fu, &fu, sizeof(fu))) + return -EFAULT; + return 0; +} + +static int ext4_ioc_setfsuuid(struct file *filp, struct super_block *sb, + struct ioc_fsuuid __user *user_fu) +{ + struct ioc_fsuuid fu; + uuid_t new_uuid; + struct ext4_sb_info *sbi = EXT4_SB(sb); + handle_t *handle; + int err, err2; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (copy_from_user(&fu, user_fu, sizeof(fu))) + return -EFAULT; + + if (fu.fu_reserved || fu.fu_reserved1 || + (fu.fu_flags & ~FS_IOC_SETFSUUID_ALL) || + fu.fu_length != sizeof(uuid_t)) + return -EINVAL; + + if (copy_from_user(&new_uuid, user_fu + 1, sizeof(uuid_t))) + return -EFAULT; + if (uuid_is_null(&new_uuid)) + return -EINVAL; + + err = mnt_want_write_file(filp); + if (err) + return err; + + handle = ext4_journal_start_sb(sb, EXT4_HT_RESIZE, 1); + if (IS_ERR(handle)) { + err = PTR_ERR(handle); + goto out_drop_write; + } + err = ext4_journal_get_write_access(handle, sbi->s_sbh); + if (err) + goto out_cancel_trans; + + /* + * Older ext4 filesystems with the group descriptor checksum feature + * but not the general metadata checksum features require all group + * descriptors to be rewritten to change the UUID. We can't do that + * here, so just bail out. + */ + if (ext4_has_feature_gdt_csum(sb) && !ext4_has_metadata_csum(sb)) { + err = -EOPNOTSUPP; + goto out_cancel_trans; + } + + /* + * Prior to the addition of metadata checksumming, the uuid was only + * used in the superblock, so for those filesystems, all we need to do + * here is update the incore uuid and write the super to disk. + * + * On a metadata_csum filesystem, every metadata object has a checksum + * that is seeded with the checksum of the uuid that was set at + * mkfs time. The seed value can be stored in the ondisk superblock + * or computed at mount time, depending on feature flags. + * + * If the csum_seed feature is not set, we need to turn on the + * csum_seed feature. If userspace did not set FORCE_INCOMPAT we have + * to bail out. Otherwise, copy the incore checksum seed to the ondisk + * superblock, set the csum_seed feature bit, and then we can update + * the incore uuid. + */ + if ((ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb)) && + !ext4_has_feature_csum_seed(sb) && + memcmp(&new_uuid, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid))) { + if (!(fu.fu_flags & FS_IOC_SETFSUUID_FORCE_INCOMPAT)) { + err = -EOPNOTSUPP; + goto out_cancel_trans; + } + sbi->s_es->s_checksum_seed = cpu_to_le32(sbi->s_csum_seed); + ext4_set_feature_csum_seed(sb); + } + memcpy(sbi->s_es->s_uuid, &new_uuid, sizeof(uuid_t)); + + err = ext4_handle_dirty_super(handle, sb); + if (err) + goto out_cancel_trans; + + /* Update incore state. */ + uuid_copy(&sb->s_uuid, &new_uuid); + invalidate_bdev(sb->s_bdev); + +out_cancel_trans: + err2 = ext4_journal_stop(handle); + if (!err) + err = err2; +out_drop_write: + mnt_drop_write_file(filp); + return err; +} + long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { struct inode *inode = file_inode(filp); @@ -1304,6 +1430,12 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) return -EOPNOTSUPP; return fsverity_ioctl_measure(filp, (void __user *)arg); + case FS_IOC_GETFSUUID: + return ext4_ioc_getfsuuid(sb, (struct ioc_fsuuid __user *)arg); + case FS_IOC_SETFSUUID: + return ext4_ioc_setfsuuid(filp, sb, + (struct ioc_fsuuid __user *)arg); + default: return -ENOTTY; }