block: move capacity from disk to part0

Move disk->capacity to part0->nr_sects and convert all users who
directly accessed the field to use {get|set}_capacity().  This is done
early to allow the __dev field to be moved.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index 3edb6cb..aa69556 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -276,7 +276,7 @@
 	gd->first_minor = d->sysminor * AOE_PARTITIONS;
 	gd->fops = &aoe_bdops;
 	gd->private_data = d;
-	gd->capacity = d->ssize;
+	set_capacity(gd, d->ssize);
 	snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
 		d->aoemajor, d->aoeminor);
 
diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 17eed8c..934800f 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -645,7 +645,7 @@
 		unsigned long flags;
 		u64 ssize;
 
-		ssize = d->gd->capacity;
+		ssize = get_capacity(d->gd);
 		bd = bdget_disk(d->gd, 0);
 
 		if (bd) {
@@ -707,7 +707,7 @@
 	if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
 		return;
 	if (d->gd != NULL) {
-		d->gd->capacity = ssize;
+		set_capacity(d->gd, ssize);
 		d->flags |= DEVFL_NEWSIZE;
 	} else
 		d->flags |= DEVFL_GDALLOC;
diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c
index a1d813a..6a8038d 100644
--- a/drivers/block/aoe/aoedev.c
+++ b/drivers/block/aoe/aoedev.c
@@ -91,7 +91,7 @@
 	}
 
 	if (d->gd)
-		d->gd->capacity = 0;
+		set_capacity(d->gd, 0);
 
 	d->flags &= ~DEVFL_UP;
 }
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index b60699c..902b95f 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -586,7 +586,7 @@
 	disk_part_iter_exit(&piter);
 
 	invalidate_partition(disk, 0);
-	disk->capacity = 0;
+	set_capacity(disk, 0);
 	disk->flags &= ~GENHD_FL_UP;
 	unlink_gendisk(disk);
 	disk_stat_set_all(disk, 0);
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 9e866a2..1cf8281 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -138,7 +138,6 @@
 	struct block_device_operations *fops;
 	struct request_queue *queue;
 	void *private_data;
-	sector_t capacity;
 
 	int flags;
 	struct device *driverfs_dev;  // FIXME: remove
@@ -411,11 +410,11 @@
 }
 static inline sector_t get_capacity(struct gendisk *disk)
 {
-	return disk->capacity;
+	return disk->part0.nr_sects;
 }
 static inline void set_capacity(struct gendisk *disk, sector_t size)
 {
-	disk->capacity = size;
+	disk->part0.nr_sects = size;
 }
 
 #ifdef CONFIG_SOLARIS_X86_PARTITION