From: Takashi Sato Subject: [RFC PATCH 2/2] Add timeout feature Date: Fri, 28 Mar 2008 18:07:36 +0900 Message-ID: <20080328180736t-sato@mail.jp.nec.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: "linux-ext4@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "xfs@oss.sgi.com" , "dm-devel@redhat.com" , "linux-kernel@vger.kernel.org" To: David Chinner Return-path: Received: from TYO202.gate.nec.co.jp ([202.32.8.206]:37366 "EHLO tyo202.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753663AbYC1JIb (ORCPT ); Fri, 28 Mar 2008 05:08:31 -0400 Sender: linux-ext4-owner@vger.kernel.org List-ID: The timeout feature is added to freeze ioctl. And new ioctl to reset the timeout period is added. o Freeze the filesystem int ioctl(int fd, int FIFREEZE, long *timeval) fd: The file descriptor of the mountpoint FIFREEZE: request code for the freeze timeval: the timeout period in seconds If it's 0 or 1, the timeout isn't set. This special case of "1" is implemented to keep the compatibility with XFS applications. Return value: 0 if the operation succeeds. Otherwise, -1 o Reset the timeout period int ioctl(int fd, int FIFREEZE_RESET_TIMEOUT, long *timeval) fd:file descriptor of mountpoint FIFREEZE_RESET_TIMEOUT: request code for reset of timeout period timeval: new timeout period in seconds Return value: 0 if the operation succeeds. Otherwise, -1 Error number: If the filesystem has already been unfrozen, errno is set to EINVAL. Signed-off-by: Takashi Sato --- drivers/md/dm.c | 2 - fs/block_dev.c | 2 + fs/buffer.c | 14 ++++++++- fs/ioctl.c | 64 ++++++++++++++++++++++++++++++++++++++++++- fs/super.c | 52 ++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_ioctl.c | 2 - fs/xfs/xfs_fsops.c | 2 - include/linux/buffer_head.h | 2 - include/linux/fs.h | 8 +++++ 9 files changed, 141 insertions(+), 7 deletions(-) diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/drivers/md/dm.c linux-2.6.25-rc7-timeout/driv ers/md/dm.c --- linux-2.6.25-rc7-freeze/drivers/md/dm.c 2008-03-26 20:14:00.000000000 +0900 +++ linux-2.6.25-rc7-timeout/drivers/md/dm.c 2008-03-26 20:10:07.000000000 +0900 @@ -1407,7 +1407,7 @@ static int lock_fs(struct mapped_device WARN_ON(md->frozen_sb); - md->frozen_sb = freeze_bdev(md->suspended_bdev); + md->frozen_sb = freeze_bdev(md->suspended_bdev, 0); if (IS_ERR(md->frozen_sb)) { r = PTR_ERR(md->frozen_sb); md->frozen_sb = NULL; diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/fs/block_dev.c linux-2.6.25-rc7-timeout/fs/bl ock_dev.c --- linux-2.6.25-rc7-freeze/fs/block_dev.c 2008-03-27 09:26:36.000000000 +0900 +++ linux-2.6.25-rc7-timeout/fs/block_dev.c 2008-03-26 20:10:19.000000000 +0900 @@ -287,6 +287,8 @@ static void init_once(struct kmem_cache /* Initialize semaphore for freeze. */ sema_init(&bdev->bd_freeze_sem, 1); + /* Setup freeze timeout function. */ + INIT_DELAYED_WORK(&bdev->bd_freeze_timeout, freeze_timeout); } static inline void __bd_forget(struct inode *inode) diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/fs/buffer.c linux-2.6.25-rc7-timeout/fs/buffe r.c --- linux-2.6.25-rc7-freeze/fs/buffer.c 2008-03-26 20:32:23.000000000 +0900 +++ linux-2.6.25-rc7-timeout/fs/buffer.c 2008-03-26 20:10:19.000000000 +0900 @@ -190,14 +190,17 @@ int fsync_bdev(struct block_device *bdev /** * freeze_bdev -- lock a filesystem and force it into a consistent state - * @bdev: blockdevice to lock + * @bdev: blockdevice to lock + * @timeout_msec: timeout period * * This takes the block device bd_mount_sem to make sure no new mounts * happen on bdev until thaw_bdev() is called. * If a superblock is found on this device, we take the s_umount semaphore * on it to make sure nobody unmounts until the snapshot creation is done. + * If timeout_msec is bigger than 0, this registers the delayed work for + * timeout of the freeze feature. */ -struct super_block *freeze_bdev(struct block_device *bdev) +struct super_block *freeze_bdev(struct block_device *bdev, long timeout_msec) { struct super_block *sb; @@ -233,6 +236,10 @@ struct super_block *freeze_bdev(struct b sync_blockdev(bdev); + /* Setup unfreeze timer. */ + if (timeout_msec > 0) + add_freeze_timeout(bdev, timeout_msec); + up(&bdev->bd_freeze_sem); return sb; /* thaw_bdev releases s->s_umount and bd_mount_sem */ @@ -255,6 +262,9 @@ void thaw_bdev(struct block_device *bdev return; } + /* Delete unfreeze timer. */ + del_freeze_timeout(bdev); + if (sb) { BUG_ON(sb->s_bdev != bdev); diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/fs/ioctl.c linux-2.6.25-rc7-timeout/fs/ioctl. c --- linux-2.6.25-rc7-freeze/fs/ioctl.c 2008-03-26 20:22:17.000000000 +0900 +++ linux-2.6.25-rc7-timeout/fs/ioctl.c 2008-03-26 20:10:19.000000000 +0900 @@ -184,6 +184,8 @@ int do_vfs_ioctl(struct file *filp, unsi break; case FIFREEZE: { + long timeout_sec; + long timeout_msec; struct super_block *sb = filp->f_path.dentry->d_inode->i_sb; if (!capable(CAP_SYS_ADMIN)) { @@ -197,8 +199,31 @@ int do_vfs_ioctl(struct file *filp, unsi break; } + /* arg(sec) to tick value. */ + error = get_user(timeout_sec, (long __user *) arg); + if (error != 0) + break; + /* + * If 1 is specified as the timeout period, + * it will be changed into 0 to keep the compatibility + * of XFS application(xfs_freeze). + */ + if (timeout_sec < 0) { + error = -EINVAL; + break; + } else if (timeout_sec < 2) { + timeout_sec = 0; + } + + timeout_msec = timeout_sec * 1000; + /* overflow case */ + if (timeout_msec < 0) { + error = -EINVAL; + break; + } + /* Freeze. */ - freeze_bdev(sb->s_bdev); + freeze_bdev(sb->s_bdev, timeout_msec); break; } @@ -216,6 +241,43 @@ int do_vfs_ioctl(struct file *filp, unsi break; } + case FIFREEZE_RESET_TIMEOUT: { + long timeout_sec; + long timeout_msec; + struct super_block *sb + = filp->f_path.dentry->d_inode->i_sb; + + if (!capable(CAP_SYS_ADMIN)) { + error = -EPERM; + break; + } + + /* arg(sec) to tick value */ + error = get_user(timeout_sec, (long __user *) arg); + if (error) + break; + timeout_msec = timeout_sec * 1000; + if (timeout_msec < 0) { + error = -EINVAL; + break; + } + + if (sb) { + down(&sb->s_bdev->bd_freeze_sem); + if (sb->s_frozen == SB_UNFROZEN) { + up(&sb->s_bdev->bd_freeze_sem); + error = -EINVAL; + break; + } + /* setup unfreeze timer */ + if (timeout_msec > 0) + add_freeze_timeout(sb->s_bdev, + timeout_msec); + up(&sb->s_bdev->bd_freeze_sem); + } + break; + } + default: if (S_ISREG(filp->f_path.dentry->d_inode->i_mode)) error = file_ioctl(filp, cmd, arg); diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/fs/super.c linux-2.6.25-rc7-timeout/fs/super. c --- linux-2.6.25-rc7-freeze/fs/super.c 2008-03-26 20:23:21.000000000 +0900 +++ linux-2.6.25-rc7-timeout/fs/super.c 2008-03-26 20:10:19.000000000 +0900 @@ -983,3 +983,55 @@ struct vfsmount *kern_mount_data(struct } EXPORT_SYMBOL_GPL(kern_mount_data); + +/* + * freeze_timeout - Thaw the filesystem. + * + * @work: work queue (delayed_work.work) + * + * Called by the delayed work when elapsing the timeout period. + * Thaw the filesystem. + */ +void freeze_timeout(struct work_struct *work) +{ + struct block_device *bd = container_of(work, + struct block_device, bd_freeze_timeout.work); + + struct super_block *sb = get_super_without_lock(bd); + + thaw_bdev(bd, sb); + + if (sb) + put_super(sb); +} +EXPORT_SYMBOL_GPL(freeze_timeout); + +/* + * add_freeze_timeout - Add timeout for freeze. + * + * @bdev: block device struct + * @timeout_msec: timeout period + * + * Add the delayed work for freeze timeout to the delayed work queue. + */ +void add_freeze_timeout(struct block_device *bdev, long timeout_msec) +{ + s64 timeout_jiffies = msecs_to_jiffies(timeout_msec); + + /* Set delayed work queue */ + cancel_delayed_work(&bdev->bd_freeze_timeout); + schedule_delayed_work(&bdev->bd_freeze_timeout, timeout_jiffies); +} + +/* + * del_freeze_timeout - Delete timeout for freeze. + * + * @bdev: block device struct + * + * Delete the delayed work for freeze timeout from the delayed work queue. + */ +void del_freeze_timeout(struct block_device *bdev) +{ + if (delayed_work_pending(&bdev->bd_freeze_timeout)) + cancel_delayed_work(&bdev->bd_freeze_timeout); +} diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/fs/xfs/linux-2.6/xfs_ioctl.c linux-2.6.25-rc7 -timeout/fs/xfs/linux-2.6/xfs_ioctl.c --- linux-2.6.25-rc7-freeze/fs/xfs/linux-2.6/xfs_ioctl.c 2008-03-26 20:23:59.000000000 +0900 +++ linux-2.6.25-rc7-timeout/fs/xfs/linux-2.6/xfs_ioctl.c 2008-03-26 20:10:19.000000000 +0900 @@ -911,7 +911,7 @@ xfs_ioctl( return -EPERM; if (inode->i_sb->s_frozen == SB_UNFROZEN) - freeze_bdev(inode->i_sb->s_bdev); + freeze_bdev(inode->i_sb->s_bdev, 0); return 0; case XFS_IOC_THAW: diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/fs/xfs/xfs_fsops.c linux-2.6.25-rc7-timeout/f s/xfs/xfs_fsops.c --- linux-2.6.25-rc7-freeze/fs/xfs/xfs_fsops.c 2008-03-26 20:24:44.000000000 +0900 +++ linux-2.6.25-rc7-timeout/fs/xfs/xfs_fsops.c 2008-03-26 20:10:19.000000000 +0900 @@ -623,7 +623,7 @@ xfs_fs_goingdown( { switch (inflags) { case XFS_FSOP_GOING_FLAGS_DEFAULT: { - struct super_block *sb = freeze_bdev(mp->m_super->s_bdev); + struct super_block *sb = freeze_bdev(mp->m_super->s_bdev, 0); if (sb && !IS_ERR(sb)) { xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT); diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/include/linux/buffer_head.h linux-2.6.25-rc7- timeout/include/linux/buffer_head.h --- linux-2.6.25-rc7-freeze/include/linux/buffer_head.h 2008-03-26 20:25:16.000000000 +0900 +++ linux-2.6.25-rc7-timeout/include/linux/buffer_head.h 2008-03-26 20:10:20.000000000 +0900 @@ -170,7 +170,7 @@ int sync_blockdev(struct block_device *b void __wait_on_buffer(struct buffer_head *); wait_queue_head_t *bh_waitq_head(struct buffer_head *bh); int fsync_bdev(struct block_device *); -struct super_block *freeze_bdev(struct block_device *); +struct super_block *freeze_bdev(struct block_device *, long timeout_msec); void thaw_bdev(struct block_device *, struct super_block *); int fsync_super(struct super_block *); int fsync_no_super(struct block_device *); diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-freeze/include/linux/fs.h linux-2.6.25-rc7-timeout/i nclude/linux/fs.h --- linux-2.6.25-rc7-freeze/include/linux/fs.h 2008-03-26 20:27:44.000000000 +0900 +++ linux-2.6.25-rc7-timeout/include/linux/fs.h 2008-03-26 20:10:20.000000000 +0900 @@ -8,6 +8,7 @@ #include #include +#include /* * It's silly to have NR_OPEN bigger than NR_FILE, but you can change @@ -225,6 +226,7 @@ extern int dir_notify_enable; #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */ #define FIFREEZE _IOWR('X', 119, int) /* Freeze */ #define FITHAW _IOWR('X', 120, int) /* Thaw */ +#define FIFREEZE_RESET_TIMEOUT _IO(0x00, 3) /* Reset freeze timeout */ #define FS_IOC_GETFLAGS _IOR('f', 1, long) #define FS_IOC_SETFLAGS _IOW('f', 2, long) @@ -551,6 +553,8 @@ struct block_device { */ unsigned long bd_private; + /* Delayed work for freeze */ + struct delayed_work bd_freeze_timeout; /* Semaphore for freeze */ struct semaphore bd_freeze_sem; }; @@ -2104,5 +2108,9 @@ int proc_nr_files(struct ctl_table *tabl int get_filesystem_list(char * buf); +extern void add_freeze_timeout(struct block_device *bdev, long timeout_msec); +extern void del_freeze_timeout(struct block_device *bdev); +extern void freeze_timeout(struct work_struct *work); + #endif /* __KERNEL__ */ #endif /* _LINUX_FS_H */