Commit 560e20e4 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Christian Brauner
Browse files

block: consolidate __invalidate_device and fsync_bdev 



We currently have two interfaces that take a block_devices and the find
a mounted file systems to flush or invaldidate data on it.  Both are a
bit problematic because they only work for the "main" block devices
that is used as s_dev for the super_block, and because they don't call
into the file system at all.

Merge the two into a new bdev_mark_dead helper that does both the
syncing and invalidation and which is properly documented.  This is
in preparation of merging the functionality into the ->mark_dead
holder operation so that it will work on additional block devices
used by a file systems and give us a single entry point for invalidation
of dead devices or media.

Note that a single standalone fsync_bdev call for an obscure ioctl
remains for now, but that one will also be deal with in a bit.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Message-Id: <20230811100828.1897174-14-hch@lst.de>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 127a5093

block/bdev.c

+28 −5
Original line number Diff line number Diff line
@@ -221,7 +221,6 @@ int fsync_bdev(struct block_device *bdev) 
	}

	return sync_blockdev(bdev);

}

EXPORT_SYMBOL(fsync_bdev);



/**

 * freeze_bdev - lock a filesystem and force it into a consistent state
@@ -960,12 +959,27 @@ int lookup_bdev(const char *pathname, dev_t *dev) 
}

EXPORT_SYMBOL(lookup_bdev);



int __invalidate_device(struct block_device *bdev, bool kill_dirty)

/**

 * bdev_mark_dead - mark a block device as dead

 * @bdev: block device to operate on

 * @surprise: indicate a surprise removal

 *

 * Tell the file system that this devices or media is dead.  If @surprise is set

 * to %true the device or media is already gone, if not we are preparing for an

 * orderly removal.

 *

 * This syncs out all dirty data and writes back inodes and then invalidates any

 * cached data in the inodes on the file system, the inodes themselves and the

 * block device mapping.

 */

void bdev_mark_dead(struct block_device *bdev, bool surprise)

{

	struct super_block *sb = get_super(bdev);

	int res = 0;



	if (sb) {

		if (!surprise)

			sync_filesystem(sb);

		/*

		 * no need to lock the super, get_super holds the

		 * read mutex so the filesystem cannot go away
@@ -973,13 +987,22 @@ int __invalidate_device(struct block_device *bdev, bool kill_dirty) 
		 * hold).

		 */

		shrink_dcache_sb(sb);

		res = invalidate_inodes(sb, kill_dirty);

		res = invalidate_inodes(sb, true);

		drop_super(sb);

	} else {

		if (!surprise)

			sync_blockdev(bdev);

	}

	invalidate_bdev(bdev);

	return res;

}

EXPORT_SYMBOL(__invalidate_device);

#ifdef CONFIG_DASD_MODULE

/*

 * Drivers should not use this directly, but the DASD driver has historically

 * had a shutdown to offline mode that doesn't actually remove the gendisk

 * that otherwise looks a lot like a safe device removal.

 */

EXPORT_SYMBOL_GPL(bdev_mark_dead);

#endif



void sync_bdevs(bool wait)

{

block/disk-events.c

+2 −2
Original line number Diff line number Diff line
@@ -281,7 +281,7 @@ bool disk_check_media_change(struct gendisk *disk) 
	if (!(events & DISK_EVENT_MEDIA_CHANGE))

		return false;



	__invalidate_device(disk->part0, true);

	bdev_mark_dead(disk->part0, true);

	set_bit(GD_NEED_PART_SCAN, &disk->state);

	return true;

}
@@ -300,7 +300,7 @@ void disk_force_media_change(struct gendisk *disk) 
{

	disk_event_uevent(disk, DISK_EVENT_MEDIA_CHANGE);

	inc_diskseq(disk);

	__invalidate_device(disk->part0, true);

	bdev_mark_dead(disk->part0, true);

	set_bit(GD_NEED_PART_SCAN, &disk->state);

}

EXPORT_SYMBOL_GPL(disk_force_media_change);

block/genhd.c

+1 −2
Original line number Diff line number Diff line
@@ -647,8 +647,7 @@ void del_gendisk(struct gendisk *disk) 
	mutex_lock(&disk->open_mutex);

	xa_for_each(&disk->part_tbl, idx, part) {

		remove_inode_hash(part->bd_inode);

		fsync_bdev(part);

		__invalidate_device(part, true);

		bdev_mark_dead(part, false);

	}

	mutex_unlock(&disk->open_mutex);

block/partitions/core.c

+1 −4
Original line number Diff line number Diff line
@@ -281,10 +281,7 @@ static void delete_partition(struct block_device *part) 
	 * looked up any more even when openers still hold references.

	 */

	remove_inode_hash(part->bd_inode);



	fsync_bdev(part);

	__invalidate_device(part, true);



	bdev_mark_dead(part, false);

	drop_partition(part);

}

drivers/s390/block/dasd.c

+2 −4
Original line number Diff line number Diff line
@@ -3626,10 +3626,8 @@ int dasd_generic_set_offline(struct ccw_device *cdev) 
		 * so sync bdev first and then wait for our queues to become

		 * empty

		 */

		if (device->block) {

			fsync_bdev(device->block->bdev);

			__invalidate_device(device->block->bdev, true);

		}

		if (device->block)

			bdev_mark_dead(device->block->bdev, false);

		dasd_schedule_device_bh(device);

		rc = wait_event_interruptible(shutdown_waitq,

					      _wait_for_empty_queues(device));