From patchwork Wed Jul 17 20:50:02 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bruce Fields X-Patchwork-Id: 2829021 Return-Path: X-Original-To: patchwork-linux-nfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 63FFB9F9A0 for ; Wed, 17 Jul 2013 20:50:54 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3DBBE2037E for ; Wed, 17 Jul 2013 20:50:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D1CC72037D for ; Wed, 17 Jul 2013 20:50:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756855Ab3GQUuY (ORCPT ); Wed, 17 Jul 2013 16:50:24 -0400 Received: from fieldses.org ([174.143.236.118]:53624 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756138Ab3GQUuU (ORCPT ); Wed, 17 Jul 2013 16:50:20 -0400 Received: from bfields by fieldses.org with local (Exim 4.76) (envelope-from ) id 1UzYfz-0008CX-Lv; Wed, 17 Jul 2013 16:50:19 -0400 From: "J. Bruce Fields" To: Al Viro Cc: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, jlayton@redhat.com, Dave Chinner , "J. Bruce Fields" , Andreas Dilger Subject: [PATCH 01/16] vfs: pull ext4's double-i_mutex-locking into common code Date: Wed, 17 Jul 2013 16:50:02 -0400 Message-Id: <1374094217-31493-3-git-send-email-bfields@redhat.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1374094217-31493-1-git-send-email-bfields@redhat.com> References: <1374094217-31493-1-git-send-email-bfields@redhat.com> Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Spam-Status: No, score=-7.3 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: "J. Bruce Fields" We want to do this elsewhere as well. Also catch any attempts to use it for directories (where this ordering would conflict with ancestor-first directory ordering in lock_rename). Cc: Andreas Dilger Cc: Dave Chinner Acked-by: Jeff Layton Acked-by: "Theodore Ts'o" Signed-off-by: J. Bruce Fields --- fs/ext4/ext4.h | 2 -- fs/ext4/ioctl.c | 4 ++-- fs/ext4/move_extent.c | 40 ++-------------------------------------- fs/inode.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 3 +++ 5 files changed, 43 insertions(+), 42 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index b577e45..c8fcdfd 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2699,8 +2699,6 @@ extern void ext4_double_down_write_data_sem(struct inode *first, struct inode *second); extern void ext4_double_up_write_data_sem(struct inode *orig_inode, struct inode *donor_inode); -void ext4_inode_double_lock(struct inode *inode1, struct inode *inode2); -void ext4_inode_double_unlock(struct inode *inode1, struct inode *inode2); extern int ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 start_orig, __u64 start_donor, __u64 len, __u64 *moved_len); diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 9491ac0..12048f7 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -129,7 +129,7 @@ static long swap_inode_boot_loader(struct super_block *sb, /* Protect orig inodes against a truncate and make sure, * that only 1 swap_inode_boot_loader is running. */ - ext4_inode_double_lock(inode, inode_bl); + lock_two_nondirectories(inode, inode_bl); truncate_inode_pages(&inode->i_data, 0); truncate_inode_pages(&inode_bl->i_data, 0); @@ -204,7 +204,7 @@ static long swap_inode_boot_loader(struct super_block *sb, ext4_inode_resume_unlocked_dio(inode); ext4_inode_resume_unlocked_dio(inode_bl); - ext4_inode_double_unlock(inode, inode_bl); + unlock_two_nondirectories(inode, inode_bl); iput(inode_bl); diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index e86dddb..f591a75 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -1203,42 +1203,6 @@ mext_check_arguments(struct inode *orig_inode, } /** - * ext4_inode_double_lock - Lock i_mutex on both @inode1 and @inode2 - * - * @inode1: the inode structure - * @inode2: the inode structure - * - * Lock two inodes' i_mutex - */ -void -ext4_inode_double_lock(struct inode *inode1, struct inode *inode2) -{ - BUG_ON(inode1 == inode2); - if (inode1 < inode2) { - mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD); - } else { - mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD); - } -} - -/** - * ext4_inode_double_unlock - Release i_mutex on both @inode1 and @inode2 - * - * @inode1: the inode that is released first - * @inode2: the inode that is released second - * - */ - -void -ext4_inode_double_unlock(struct inode *inode1, struct inode *inode2) -{ - mutex_unlock(&inode1->i_mutex); - mutex_unlock(&inode2->i_mutex); -} - -/** * ext4_move_extents - Exchange the specified range of a file * * @o_filp: file structure of the original file @@ -1327,7 +1291,7 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, return -EINVAL; } /* Protect orig and donor inodes against a truncate */ - ext4_inode_double_lock(orig_inode, donor_inode); + lock_two_nondirectories(orig_inode, donor_inode); /* Wait for all existing dio workers */ ext4_inode_block_unlocked_dio(orig_inode); @@ -1535,7 +1499,7 @@ out: ext4_double_up_write_data_sem(orig_inode, donor_inode); ext4_inode_resume_unlocked_dio(orig_inode); ext4_inode_resume_unlocked_dio(donor_inode); - ext4_inode_double_unlock(orig_inode, donor_inode); + unlock_two_nondirectories(orig_inode, donor_inode); return ret; } diff --git a/fs/inode.c b/fs/inode.c index d6dfb09..57d273e 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -982,6 +982,42 @@ void unlock_new_inode(struct inode *inode) EXPORT_SYMBOL(unlock_new_inode); /** + * lock_two_nondirectories - take two i_mutexes on non-directory objects + * @inode1: first inode to lock + * @inode2: second inode to lock + */ +void lock_two_nondirectories(struct inode *inode1, struct inode *inode2) +{ + WARN_ON_ONCE(S_ISDIR(inode1->i_mode)); + if (inode1 == inode2 || !inode2) { + mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT); + return; + } + WARN_ON_ONCE(S_ISDIR(inode2->i_mode)); + if (inode1 < inode2) { + mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD); + } else { + mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD); + } +} +EXPORT_SYMBOL(lock_two_nondirectories); + +/** + * unlock_two_nondirectories - release locks from lock_two_nondirectories() + * @inode1: first inode to unlock + * @inode2: second inode to unlock + */ +void unlock_two_nondirectories(struct inode *inode1, struct inode *inode2) +{ + mutex_unlock(&inode1->i_mutex); + if (inode2 && inode2 != inode1) + mutex_unlock(&inode2->i_mutex); +} +EXPORT_SYMBOL(unlock_two_nondirectories); + +/** * iget5_locked - obtain an inode from a mounted file system * @sb: super block of file system * @hashval: hash value (usually inode number) to get diff --git a/include/linux/fs.h b/include/linux/fs.h index 9818747..431427a 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -636,6 +636,9 @@ enum inode_i_mutex_lock_class I_MUTEX_QUOTA }; +void lock_two_nondirectories(struct inode *, struct inode*); +void unlock_two_nondirectories(struct inode *, struct inode*); + /* * NOTE: in a 32bit arch with a preemptable kernel and * an UP compile the i_size_read/write must be atomic