Commit 4fc6441a authored by Anand Jain's avatar Anand Jain Committed by David Sterba
Browse files

btrfs: wait part of the write_dev_flush() can be separated out 



Submit and wait parts of write_dev_flush() can be split into two
separate functions for better readability.

Signed-off-by: default avatarAnand Jain <anand.jain@oracle.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent cea7c8bf

fs/btrfs/disk-io.c

+31 −28
Original line number Diff line number Diff line
@@ -3488,37 +3488,16 @@ static void btrfs_end_empty_barrier(struct bio *bio) 
}



/*

 * trigger flushes for one the devices.  If you pass wait == 0, the flushes are

 * sent down.  With wait == 1, it waits for the previous flush.

 *

 * any device where the flush fails with eopnotsupp are flagged as not-barrier

 * capable

 * Submit a flush request to the device if it supports it. Error handling is

 * done in the waiting counterpart.

 */

static int write_dev_flush(struct btrfs_device *device, int wait)

static void write_dev_flush(struct btrfs_device *device)

{

	struct request_queue *q = bdev_get_queue(device->bdev);

	struct bio *bio;

	int ret = 0;



	if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags))

		return 0;



	if (wait) {

		bio = device->flush_bio;

		wait_for_completion(&device->flush_wait);



		if (bio->bi_error) {

			ret = bio->bi_error;

			btrfs_dev_stat_inc_and_print(device,

				BTRFS_DEV_STAT_FLUSH_ERRS);

		}



		/* drop the reference from the wait == 0 run */

		bio_put(bio);

		device->flush_bio = NULL;



		return ret;

	}

		return;



	/*

	 * one reference for us, and we leave it for the
@@ -3535,8 +3514,32 @@ static int write_dev_flush(struct btrfs_device *device, int wait) 


	bio_get(bio);

	btrfsic_submit_bio(bio);

}



/*

 * If the flush bio has been submitted by write_dev_flush, wait for it.

 */

static int wait_dev_flush(struct btrfs_device *device)

{

	int ret = 0;

	struct bio *bio = device->flush_bio;



	if (!bio)

		return 0;



	wait_for_completion(&device->flush_wait);



	if (bio->bi_error) {

		ret = bio->bi_error;

		btrfs_dev_stat_inc_and_print(device,

				BTRFS_DEV_STAT_FLUSH_ERRS);

	}



	/* drop the reference from the wait == 0 run */

	bio_put(bio);

	device->flush_bio = NULL;



	return ret;

}



static int check_barrier_error(struct btrfs_fs_devices *fsdevs)
@@ -3577,7 +3580,7 @@ static int barrier_all_devices(struct btrfs_fs_info *info) 
		if (!dev->in_fs_metadata || !dev->writeable)

			continue;



		write_dev_flush(dev, 0);

		write_dev_flush(dev);

		dev->last_flush_error = 0;

	}
@@ -3592,7 +3595,7 @@ static int barrier_all_devices(struct btrfs_fs_info *info) 
		if (!dev->in_fs_metadata || !dev->writeable)

			continue;



		ret = write_dev_flush(dev, 1);

		ret = wait_dev_flush(dev);

		if (ret) {

			dev->last_flush_error = ret;

			errors_wait++;