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Message-Id: <20080401212204t-sato@mail.jp.nec.com>
Date: Tue, 1 Apr 2008 21:22:04 +0900
From: Takashi Sato <t-sato@...jp.nec.com>
To: David Chinner <dgc@....com>
Cc: "linux-ext4@...r.kernel.org" <linux-ext4@...r.kernel.org>,
"xfs@....sgi.com" <xfs@....sgi.com>,
"dm-devel@...hat.com" <dm-devel@...hat.com>,
"linux-fsdevel@...r.kernel.org" <linux-fsdevel@...r.kernel.org>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: [RFC PATCH 3/3] Add timeout feature
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 <t-sato@...jp.nec.com>
Signed-off-by: Masayuki Hamaguchi <m-hamaguchi@...jp.nec.com>
---
drivers/md/dm.c | 2 -
fs/block_dev.c | 2 +
fs/buffer.c | 14 ++++++++-
fs/ioctl.c | 64 +++++++++++++++++++++++++++++++++++++++++++-
fs/super.c | 52 +++++++++++++++++++++++++++++++++++
fs/xfs/xfs_fsops.c | 2 -
include/linux/buffer_head.h | 2 -
include/linux/fs.h | 8 +++++
8 files changed, 140 insertions(+), 6 deletions(-)
diff -uprN -X /home/sho/pub/MC/freeze-set/dontdiff linux-2.6.25-rc7-xfs/drivers/md/dm.c linux-2.6.25-rc7-timeout/drivers
/md/dm.c
--- linux-2.6.25-rc7-xfs/drivers/md/dm.c 2008-04-01 14:21:37.000000000 +0900
+++ linux-2.6.25-rc7-timeout/drivers/md/dm.c 2008-04-01 13:25:11.000000000 +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-xfs/fs/block_dev.c linux-2.6.25-rc7-timeout/fs/block
_dev.c
--- linux-2.6.25-rc7-xfs/fs/block_dev.c 2008-04-01 14:22:34.000000000 +0900
+++ linux-2.6.25-rc7-timeout/fs/block_dev.c 2008-04-01 13:27:38.000000000 +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-xfs/fs/buffer.c linux-2.6.25-rc7-timeout/fs/buffer.c
--- linux-2.6.25-rc7-xfs/fs/buffer.c 2008-04-01 14:22:26.000000000 +0900
+++ linux-2.6.25-rc7-timeout/fs/buffer.c 2008-04-01 13:27:14.000000000 +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-xfs/fs/ioctl.c linux-2.6.25-rc7-timeout/fs/ioctl.c
--- linux-2.6.25-rc7-xfs/fs/ioctl.c 2008-04-01 14:22:38.000000000 +0900
+++ linux-2.6.25-rc7-timeout/fs/ioctl.c 2008-04-01 13:27:46.000000000 +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-xfs/fs/super.c linux-2.6.25-rc7-timeout/fs/super.c
--- linux-2.6.25-rc7-xfs/fs/super.c 2008-04-01 14:22:34.000000000 +0900
+++ linux-2.6.25-rc7-timeout/fs/super.c 2008-04-01 13:27:41.000000000 +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-xfs/fs/xfs/xfs_fsops.c linux-2.6.25-rc7-timeout/fs/x
fs/xfs_fsops.c
--- linux-2.6.25-rc7-xfs/fs/xfs/xfs_fsops.c 2008-04-01 14:22:33.000000000 +0900
+++ linux-2.6.25-rc7-timeout/fs/xfs/xfs_fsops.c 2008-04-01 13:27:35.000000000 +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-xfs/include/linux/buffer_head.h linux-2.6.25-rc7-tim
eout/include/linux/buffer_head.h
--- linux-2.6.25-rc7-xfs/include/linux/buffer_head.h 2008-04-01 14:22:39.000000000 +0900
+++ linux-2.6.25-rc7-timeout/include/linux/buffer_head.h 2008-04-01 13:27:53.000000000 +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-xfs/include/linux/fs.h linux-2.6.25-rc7-timeout/incl
ude/linux/fs.h
--- linux-2.6.25-rc7-xfs/include/linux/fs.h 2008-04-01 14:22:39.000000000 +0900
+++ linux-2.6.25-rc7-timeout/include/linux/fs.h 2008-04-01 13:27:53.000000000 +0900
@@ -8,6 +8,7 @@
#include <linux/limits.h>
#include <linux/ioctl.h>
+#include <linux/workqueue.h>
/*
* 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 */
--
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