Commit fd5d8062 authored by Jens Axboe's avatar Jens Axboe
Browse files

block: convert blkdev_issue_flush() to use empty barriers 



Then we can get rid of ->issue_flush_fn() and all the driver private
implementations of that.

Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent bf2de6f5

block/ll_rw_blk.c

+36 −20
Original line number Diff line number Diff line
@@ -304,23 +304,6 @@ int blk_queue_ordered(struct request_queue *q, unsigned ordered, 


EXPORT_SYMBOL(blk_queue_ordered);



/**

 * blk_queue_issue_flush_fn - set function for issuing a flush

 * @q:     the request queue

 * @iff:   the function to be called issuing the flush

 *

 * Description:

 *   If a driver supports issuing a flush command, the support is notified

 *   to the block layer by defining it through this call.

 *

 **/

void blk_queue_issue_flush_fn(struct request_queue *q, issue_flush_fn *iff)

{

	q->issue_flush_fn = iff;

}



EXPORT_SYMBOL(blk_queue_issue_flush_fn);



/*

 * Cache flushing for ordered writes handling

 */
@@ -2666,6 +2649,14 @@ int blk_execute_rq(struct request_queue *q, struct gendisk *bd_disk, 


EXPORT_SYMBOL(blk_execute_rq);



static void bio_end_empty_barrier(struct bio *bio, int err)

{

	if (err)

		clear_bit(BIO_UPTODATE, &bio->bi_flags);



	complete(bio->bi_private);

}



/**

 * blkdev_issue_flush - queue a flush

 * @bdev:	blockdev to issue flush for
@@ -2678,7 +2669,10 @@ EXPORT_SYMBOL(blk_execute_rq); 
 */

int blkdev_issue_flush(struct block_device *bdev, sector_t *error_sector)

{

	DECLARE_COMPLETION_ONSTACK(wait);

	struct request_queue *q;

	struct bio *bio;

	int ret;



	if (bdev->bd_disk == NULL)

		return -ENXIO;
@@ -2686,10 +2680,32 @@ int blkdev_issue_flush(struct block_device *bdev, sector_t *error_sector) 
	q = bdev_get_queue(bdev);

	if (!q)

		return -ENXIO;

	if (!q->issue_flush_fn)

		return -EOPNOTSUPP;



	return q->issue_flush_fn(q, bdev->bd_disk, error_sector);

	bio = bio_alloc(GFP_KERNEL, 0);

	if (!bio)

		return -ENOMEM;



	bio->bi_end_io = bio_end_empty_barrier;

	bio->bi_private = &wait;

	bio->bi_bdev = bdev;

	submit_bio(1 << BIO_RW_BARRIER, bio);



	wait_for_completion(&wait);



	/*

	 * The driver must store the error location in ->bi_sector, if

	 * it supports it. For non-stacked drivers, this should be copied

	 * from rq->sector.

	 */

	if (error_sector)

		*error_sector = bio->bi_sector;



	ret = 0;

	if (!bio_flagged(bio, BIO_UPTODATE))

		ret = -EIO;



	bio_put(bio);

	return ret;

}



EXPORT_SYMBOL(blkdev_issue_flush);

drivers/block/ps3disk.c

+0 −21
Original line number Diff line number Diff line
@@ -414,26 +414,6 @@ static void ps3disk_prepare_flush(struct request_queue *q, struct request *req) 
	req->cmd_type = REQ_TYPE_FLUSH;

}



static int ps3disk_issue_flush(struct request_queue *q, struct gendisk *gendisk,

			       sector_t *sector)

{

	struct ps3_storage_device *dev = q->queuedata;

	struct request *req;

	int res;



	dev_dbg(&dev->sbd.core, "%s:%u\n", __func__, __LINE__);



	req = blk_get_request(q, WRITE, __GFP_WAIT);

	ps3disk_prepare_flush(q, req);

	res = blk_execute_rq(q, gendisk, req, 0);

	if (res)

		dev_err(&dev->sbd.core, "%s:%u: flush request failed %d\n",

			__func__, __LINE__, res);

	blk_put_request(req);

	return res;

}





static unsigned long ps3disk_mask;



static DEFINE_MUTEX(ps3disk_mask_mutex);
@@ -506,7 +486,6 @@ static int __devinit ps3disk_probe(struct ps3_system_bus_device *_dev) 
	blk_queue_dma_alignment(queue, dev->blk_size-1);

	blk_queue_hardsect_size(queue, dev->blk_size);



	blk_queue_issue_flush_fn(queue, ps3disk_issue_flush);

	blk_queue_ordered(queue, QUEUE_ORDERED_DRAIN_FLUSH,

			  ps3disk_prepare_flush);

drivers/ide/ide-disk.c

+0 −29
Original line number Diff line number Diff line
@@ -716,32 +716,6 @@ static void idedisk_prepare_flush(struct request_queue *q, struct request *rq) 
	rq->buffer = rq->cmd;

}



static int idedisk_issue_flush(struct request_queue *q, struct gendisk *disk,

			       sector_t *error_sector)

{

	ide_drive_t *drive = q->queuedata;

	struct request *rq;

	int ret;



	if (!drive->wcache)

		return 0;



	rq = blk_get_request(q, WRITE, __GFP_WAIT);



	idedisk_prepare_flush(q, rq);



	ret = blk_execute_rq(q, disk, rq, 0);



	/*

	 * if we failed and caller wants error offset, get it

	 */

	if (ret && error_sector)

		*error_sector = ide_get_error_location(drive, rq->cmd);



	blk_put_request(rq);

	return ret;

}



/*

 * This is tightly woven into the driver->do_special can not touch.

 * DON'T do it again until a total personality rewrite is committed.
@@ -781,7 +755,6 @@ static void update_ordered(ide_drive_t *drive) 
	struct hd_driveid *id = drive->id;

	unsigned ordered = QUEUE_ORDERED_NONE;

	prepare_flush_fn *prep_fn = NULL;

	issue_flush_fn *issue_fn = NULL;



	if (drive->wcache) {

		unsigned long long capacity;
@@ -805,13 +778,11 @@ static void update_ordered(ide_drive_t *drive) 
		if (barrier) {

			ordered = QUEUE_ORDERED_DRAIN_FLUSH;

			prep_fn = idedisk_prepare_flush;

			issue_fn = idedisk_issue_flush;

		}

	} else

		ordered = QUEUE_ORDERED_DRAIN;



	blk_queue_ordered(drive->queue, ordered, prep_fn);

	blk_queue_issue_flush_fn(drive->queue, issue_fn);

}



static int write_cache(ide_drive_t *drive, int arg)

drivers/md/dm-table.c

+0 −28
Original line number Diff line number Diff line
@@ -999,33 +999,6 @@ void dm_table_unplug_all(struct dm_table *t) 
	}

}



int dm_table_flush_all(struct dm_table *t)

{

	struct list_head *d, *devices = dm_table_get_devices(t);

	int ret = 0;

	unsigned i;



	for (i = 0; i < t->num_targets; i++)

		if (t->targets[i].type->flush)

			t->targets[i].type->flush(&t->targets[i]);



	for (d = devices->next; d != devices; d = d->next) {

		struct dm_dev *dd = list_entry(d, struct dm_dev, list);

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

		int err;



		if (!q->issue_flush_fn)

			err = -EOPNOTSUPP;

		else

			err = q->issue_flush_fn(q, dd->bdev->bd_disk, NULL);



		if (!ret)

			ret = err;

	}



	return ret;

}



struct mapped_device *dm_table_get_md(struct dm_table *t)

{

	dm_get(t->md);
@@ -1043,4 +1016,3 @@ EXPORT_SYMBOL(dm_table_get_md); 
EXPORT_SYMBOL(dm_table_put);

EXPORT_SYMBOL(dm_table_get);

EXPORT_SYMBOL(dm_table_unplug_all);
 
EXPORT_SYMBOL(dm_table_flush_all);

drivers/md/dm.c

+0 −16
Original line number Diff line number Diff line
@@ -840,21 +840,6 @@ static int dm_request(struct request_queue *q, struct bio *bio) 
	return 0;

}



static int dm_flush_all(struct request_queue *q, struct gendisk *disk,

			sector_t *error_sector)

{

	struct mapped_device *md = q->queuedata;

	struct dm_table *map = dm_get_table(md);

	int ret = -ENXIO;



	if (map) {

		ret = dm_table_flush_all(map);

		dm_table_put(map);

	}



	return ret;

}



static void dm_unplug_all(struct request_queue *q)

{

	struct mapped_device *md = q->queuedata;
@@ -1003,7 +988,6 @@ static struct mapped_device *alloc_dev(int minor) 
	blk_queue_make_request(md->queue, dm_request);

	blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);

	md->queue->unplug_fn = dm_unplug_all;

	md->queue->issue_flush_fn = dm_flush_all;



	md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache);

	if (!md->io_pool)