block: remove the nr_sects field in struct hd_struct

Now that the hd_struct always has a block device attached to it, there is
no need for having two size field that just get out of sync.

Additionally the field in hd_struct did not use proper serialization,
possibly allowing for torn writes.  By only using the block_device field
this problem also gets fixed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de>			[bcache]
Acked-by: Chao Yu <yuchao0@huawei.com>			[f2fs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

6 files changed, 6 insertions, 12 deletions

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index d643c67be6ac..d2ce1ddc192d 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1241,7 +1241,6 @@ static int __loop_clr_fd(struct loop_device *lo, bool release)
 	set_capacity(lo->lo_disk, 0);
 	loop_sysfs_exit(lo);
 	if (bdev) {
-		bd_set_nr_sectors(bdev, 0);
 		/* let user-space know about this change */
 		kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
 	}
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 45b0423ef2c5..014683968ce1 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1132,7 +1132,7 @@ static void nbd_bdev_reset(struct block_device *bdev)
 {
 	if (bdev->bd_openers > 1)
 		return;
-	bd_set_nr_sectors(bdev, 0);
+	set_capacity(bdev->bd_disk, 0);
 }
 
 static void nbd_parse_flags(struct nbd_device *nbd)
diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h
index c6ea5d38c509..0762db247b41 100644
--- a/drivers/block/xen-blkback/common.h
+++ b/drivers/block/xen-blkback/common.h
@@ -358,9 +358,7 @@ struct pending_req {
 };
 
 
-#define vbd_sz(_v)	((_v)->bdev->bd_part ? \
-			 (_v)->bdev->bd_part->nr_sects : \
-			  get_capacity((_v)->bdev->bd_disk))
+#define vbd_sz(_v)	bdev_nr_sectors((_v)->bdev)
 
 #define xen_blkif_get(_b) (atomic_inc(&(_b)->refcnt))
 #define xen_blkif_put(_b)				\
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index c55d3c58a7ef..04fa40868fbe 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1408,7 +1408,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size)
 			q->limits.raid_partial_stripes_expensive;
 
 	ret = bcache_device_init(&dc->disk, block_size,
-			 dc->bdev->bd_part->nr_sects - dc->sb.data_offset,
+			 bdev_nr_sectors(dc->bdev) - dc->sb.data_offset,
 			 dc->bdev, &bcache_cached_ops);
 	if (ret)
 		return ret;
diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c
index 3359559517bf..304eba1acf16 100644
--- a/drivers/s390/block/dasd_ioctl.c
+++ b/drivers/s390/block/dasd_ioctl.c
@@ -54,8 +54,6 @@ dasd_ioctl_enable(struct block_device *bdev)
 		return -ENODEV;
 
 	dasd_enable_device(base);
-	/* Formatting the dasd device can change the capacity. */
-	bd_set_nr_sectors(bdev, get_capacity(base->block->gdp));
 	dasd_put_device(base);
 	return 0;
 }
@@ -88,7 +86,7 @@ dasd_ioctl_disable(struct block_device *bdev)
 	 * Set i_size to zero, since read, write, etc. check against this
 	 * value.
 	 */
-	bd_set_nr_sectors(bdev, 0);
+	set_capacity(bdev->bd_disk, 0);
 	dasd_put_device(base);
 	return 0;
 }
diff --git a/drivers/target/target_core_pscsi.c b/drivers/target/target_core_pscsi.c
index 4e37fa9b409d..7994f27e4527 100644
--- a/drivers/target/target_core_pscsi.c
+++ b/drivers/target/target_core_pscsi.c
@@ -1029,9 +1029,8 @@ static sector_t pscsi_get_blocks(struct se_device *dev)
 {
 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 
-	if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
-		return pdv->pdv_bd->bd_part->nr_sects;
-
+	if (pdv->pdv_bd)
+		return bdev_nr_sectors(pdv->pdv_bd);
 	return 0;
 }