Commit f31e7e40 authored by Dmitry Monakhov's avatar Dmitry Monakhov Committed by Jens Axboe
Browse files

blkdev: move blkdev_issue helper functions to separate file 



Move blkdev_issue_discard from blk-barrier.c because it is
not barrier related.
Later the file will be populated by other helpers.

Signed-off-by: default avatarDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent f17e232e

block/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 
obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \

			blk-barrier.o blk-settings.o blk-ioc.o blk-map.o \

			blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \

			blk-iopoll.o ioctl.o genhd.o scsi_ioctl.o

			blk-iopoll.o blk-lib.o ioctl.o genhd.o scsi_ioctl.o



obj-$(CONFIG_BLK_DEV_BSG)	+= bsg.o

obj-$(CONFIG_BLK_CGROUP)	+= blk-cgroup.o

block/blk-barrier.c

+0 −104
Original line number Diff line number Diff line
@@ -347,107 +347,3 @@ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, 
	return ret;

}

EXPORT_SYMBOL(blkdev_issue_flush);
 


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

{

	if (err) {

		if (err == -EOPNOTSUPP)

			set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);

		clear_bit(BIO_UPTODATE, &bio->bi_flags);

	}



	if (bio->bi_private)

		complete(bio->bi_private);

	__free_page(bio_page(bio));



	bio_put(bio);

}



/**

 * blkdev_issue_discard - queue a discard

 * @bdev:	blockdev to issue discard for

 * @sector:	start sector

 * @nr_sects:	number of sectors to discard

 * @gfp_mask:	memory allocation flags (for bio_alloc)

 * @flags:	BLKDEV_IFL_* flags to control behaviour

 *

 * Description:

 *    Issue a discard request for the sectors in question.

 */

int blkdev_issue_discard(struct block_device *bdev, sector_t sector,

		sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)

{

	DECLARE_COMPLETION_ONSTACK(wait);

	struct request_queue *q = bdev_get_queue(bdev);

	int type = flags & BLKDEV_IFL_BARRIER ?

		DISCARD_BARRIER : DISCARD_NOBARRIER;

	struct bio *bio;

	struct page *page;

	int ret = 0;



	if (!q)

		return -ENXIO;



	if (!blk_queue_discard(q))

		return -EOPNOTSUPP;



	while (nr_sects && !ret) {

		unsigned int sector_size = q->limits.logical_block_size;

		unsigned int max_discard_sectors =

			min(q->limits.max_discard_sectors, UINT_MAX >> 9);



		bio = bio_alloc(gfp_mask, 1);

		if (!bio)

			goto out;

		bio->bi_sector = sector;

		bio->bi_end_io = blkdev_discard_end_io;

		bio->bi_bdev = bdev;

		if (flags & BLKDEV_IFL_WAIT)

			bio->bi_private = &wait;



		/*

		 * Add a zeroed one-sector payload as that's what

		 * our current implementations need.  If we'll ever need

		 * more the interface will need revisiting.

		 */

		page = alloc_page(gfp_mask | __GFP_ZERO);

		if (!page)

			goto out_free_bio;

		if (bio_add_pc_page(q, bio, page, sector_size, 0) < sector_size)

			goto out_free_page;



		/*

		 * And override the bio size - the way discard works we

		 * touch many more blocks on disk than the actual payload

		 * length.

		 */

		if (nr_sects > max_discard_sectors) {

			bio->bi_size = max_discard_sectors << 9;

			nr_sects -= max_discard_sectors;

			sector += max_discard_sectors;

		} else {

			bio->bi_size = nr_sects << 9;

			nr_sects = 0;

		}



		bio_get(bio);

		submit_bio(type, bio);



		if (flags & BLKDEV_IFL_WAIT)

			wait_for_completion(&wait);



		if (bio_flagged(bio, BIO_EOPNOTSUPP))

			ret = -EOPNOTSUPP;

		else if (!bio_flagged(bio, BIO_UPTODATE))

			ret = -EIO;

		bio_put(bio);

	}

	return ret;

out_free_page:

	__free_page(page);

out_free_bio:

	bio_put(bio);

out:

	return -ENOMEM;

}

EXPORT_SYMBOL(blkdev_issue_discard);

block/blk-lib.c

0 → 100644
+114 −0
Original line number Diff line number Diff line 
/*

 * Functions related to generic helpers functions

 */

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/bio.h>

#include <linux/blkdev.h>

#include <linux/scatterlist.h>



#include "blk.h"



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

{

	if (err) {

		if (err == -EOPNOTSUPP)

			set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);

		clear_bit(BIO_UPTODATE, &bio->bi_flags);

	}



	if (bio->bi_private)

		complete(bio->bi_private);

	__free_page(bio_page(bio));



	bio_put(bio);

}



/**

 * blkdev_issue_discard - queue a discard

 * @bdev:	blockdev to issue discard for

 * @sector:	start sector

 * @nr_sects:	number of sectors to discard

 * @gfp_mask:	memory allocation flags (for bio_alloc)

 * @flags:	BLKDEV_IFL_* flags to control behaviour

 *

 * Description:

 *    Issue a discard request for the sectors in question.

 */

int blkdev_issue_discard(struct block_device *bdev, sector_t sector,

		sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)

{

	DECLARE_COMPLETION_ONSTACK(wait);

	struct request_queue *q = bdev_get_queue(bdev);

	int type = flags & BLKDEV_IFL_BARRIER ?

		DISCARD_BARRIER : DISCARD_NOBARRIER;

	struct bio *bio;

	struct page *page;

	int ret = 0;



	if (!q)

		return -ENXIO;



	if (!blk_queue_discard(q))

		return -EOPNOTSUPP;



	while (nr_sects && !ret) {

		unsigned int sector_size = q->limits.logical_block_size;

		unsigned int max_discard_sectors =

			min(q->limits.max_discard_sectors, UINT_MAX >> 9);



		bio = bio_alloc(gfp_mask, 1);

		if (!bio)

			goto out;

		bio->bi_sector = sector;

		bio->bi_end_io = blkdev_discard_end_io;

		bio->bi_bdev = bdev;

		if (flags & BLKDEV_IFL_WAIT)

			bio->bi_private = &wait;



		/*

		 * Add a zeroed one-sector payload as that's what

		 * our current implementations need.  If we'll ever need

		 * more the interface will need revisiting.

		 */

		page = alloc_page(gfp_mask | __GFP_ZERO);

		if (!page)

			goto out_free_bio;

		if (bio_add_pc_page(q, bio, page, sector_size, 0) < sector_size)

			goto out_free_page;



		/*

		 * And override the bio size - the way discard works we

		 * touch many more blocks on disk than the actual payload

		 * length.

		 */

		if (nr_sects > max_discard_sectors) {

			bio->bi_size = max_discard_sectors << 9;

			nr_sects -= max_discard_sectors;

			sector += max_discard_sectors;

		} else {

			bio->bi_size = nr_sects << 9;

			nr_sects = 0;

		}



		bio_get(bio);

		submit_bio(type, bio);



		if (flags & BLKDEV_IFL_WAIT)

			wait_for_completion(&wait);



		if (bio_flagged(bio, BIO_EOPNOTSUPP))

			ret = -EOPNOTSUPP;

		else if (!bio_flagged(bio, BIO_UPTODATE))

			ret = -EIO;

		bio_put(bio);

	}

	return ret;

out_free_page:

	__free_page(page);

out_free_bio:

	bio_put(bio);

out:

	return -ENOMEM;

}

EXPORT_SYMBOL(blkdev_issue_discard);