From: Theodore Ts'o Subject: [FOR-STABLE 05/20] ext4: elevate write count for migrate ioctl Date: Sun, 16 Nov 2008 11:05:25 -0500 Message-ID: <1226851540-8032-6-git-send-email-tytso@mit.edu> References: <1226851540-8032-1-git-send-email-tytso@mit.edu> <1226851540-8032-2-git-send-email-tytso@mit.edu> <1226851540-8032-3-git-send-email-tytso@mit.edu> <1226851540-8032-4-git-send-email-tytso@mit.edu> <1226851540-8032-5-git-send-email-tytso@mit.edu> Cc: Ext4 Developers List , "Aneesh Kumar K.V" , "Theodore Ts'o" To: stable@kernel.org Return-path: Received: from www.church-of-our-saviour.ORG ([69.25.196.31]:44747 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753123AbYKPQiU (ORCPT ); Sun, 16 Nov 2008 11:38:20 -0500 In-Reply-To: <1226851540-8032-5-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Aneesh Kumar K.V The migrate ioctl writes to the filsystem, so we need to elevate the write count. Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" (cherry picked from commit 2a43a878001cc5cb7c3c7be2e8dad0a1aeb939b0) --- fs/ext4/ext4.h | 3 +-- fs/ext4/ioctl.c | 21 ++++++++++++++++++++- fs/ext4/migrate.c | 10 +--------- 3 files changed, 22 insertions(+), 12 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 2950032..9f62743 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1083,8 +1083,7 @@ extern long ext4_ioctl(struct file *, unsigned int, unsigned long); extern long ext4_compat_ioctl (struct file *, unsigned int, unsigned long); /* migrate.c */ -extern int ext4_ext_migrate(struct inode *, struct file *, unsigned int, - unsigned long); +extern int ext4_ext_migrate(struct inode *); /* namei.c */ extern int ext4_orphan_add(handle_t *, struct inode *); extern int ext4_orphan_del(handle_t *, struct inode *); diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 7a6c2f1..306bfd4 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -267,7 +267,26 @@ setversion_out: } case EXT4_IOC_MIGRATE: - return ext4_ext_migrate(inode, filp, cmd, arg); + { + int err; + if (!is_owner_or_cap(inode)) + return -EACCES; + + err = mnt_want_write(filp->f_path.mnt); + if (err) + return err; + /* + * inode_mutex prevent write and truncate on the file. + * Read still goes through. We take i_data_sem in + * ext4_ext_swap_inode_data before we switch the + * inode format to prevent read. + */ + mutex_lock(&(inode->i_mutex)); + err = ext4_ext_migrate(inode); + mutex_unlock(&(inode->i_mutex)); + mnt_drop_write(filp->f_path.mnt); + return err; + } default: return -ENOTTY; diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c index 46fc0b5..f2a9cf4 100644 --- a/fs/ext4/migrate.c +++ b/fs/ext4/migrate.c @@ -447,8 +447,7 @@ static int free_ext_block(handle_t *handle, struct inode *inode) } -int ext4_ext_migrate(struct inode *inode, struct file *filp, - unsigned int cmd, unsigned long arg) +int ext4_ext_migrate(struct inode *inode) { handle_t *handle; int retval = 0, i; @@ -516,12 +515,6 @@ int ext4_ext_migrate(struct inode *inode, struct file *filp, * when we add extents we extent the journal */ /* - * inode_mutex prevent write and truncate on the file. Read still goes - * through. We take i_data_sem in ext4_ext_swap_inode_data before we - * switch the inode format to prevent read. - */ - mutex_lock(&(inode->i_mutex)); - /* * Even though we take i_mutex we can still cause block allocation * via mmap write to holes. If we have allocated new blocks we fail * migrate. New block allocation will clear EXT4_EXT_MIGRATE flag. @@ -623,7 +616,6 @@ err_out: tmp_inode->i_nlink = 0; ext4_journal_stop(handle); - mutex_unlock(&(inode->i_mutex)); if (tmp_inode) iput(tmp_inode); -- 1.6.0.4.8.g36f27.dirty