[PATCH 8/8] block: remove bdget/bdput

[Christoph Hellwig <hch@xxxxxx>]

Now that we've stopped using inode references for anything meaninful
in the block layer get rid of the helpers for it and just open code
the places that look up a block device by dev_t and drop the main
inode reference held by the device model.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 block/genhd.c           |  4 ++--
 block/partitions/core.c |  8 ++++----
 fs/block_dev.c          | 34 ++++++++++------------------------
 include/linux/blkdev.h  |  1 -
 4 files changed, 16 insertions(+), 31 deletions(-)

diff --git a/block/genhd.c b/block/genhd.c
index e6d782714ad3..3ea27bee0615 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1081,7 +1081,7 @@ static void disk_release(struct device *dev)
 	xa_destroy(&disk->part_tbl);
 	if (test_bit(GD_QUEUE_REF, &disk->state) && disk->queue)
 		blk_put_queue(disk->queue);
-	bdput(disk->part0);
+	iput(disk->part0->bd_inode); /* actually frees the disk */
 }
 struct class block_class = {
 	.name		= "block",
@@ -1266,7 +1266,7 @@ struct gendisk *__alloc_disk_node(int minors, int node_id)
 
 out_destroy_part_tbl:
 	xa_destroy(&disk->part_tbl);
-	bdput(disk->part0);
+	iput(disk->part0->bd_inode);
 out_free_disk:
 	kfree(disk);
 	return NULL;
diff --git a/block/partitions/core.c b/block/partitions/core.c
index 9902b1635b7d..4397ac9f905e 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -261,7 +261,7 @@ static void part_release(struct device *dev)
 {
 	if (MAJOR(dev->devt) == BLOCK_EXT_MAJOR)
 		blk_free_ext_minor(MINOR(dev->devt));
-	bdput(dev_to_bdev(dev));
+	iput(dev_to_bdev(dev)->bd_inode);
 }
 
 static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
@@ -360,7 +360,7 @@ static struct block_device *add_partition(struct gendisk *disk, int partno,
 		err = -ENOMEM;
 		bdev->bd_meta_info = kmemdup(info, sizeof(*info), GFP_KERNEL);
 		if (!bdev->bd_meta_info)
-			goto out_bdput;
+			goto out_iput;
 	}
 
 	pdev = &bdev->bd_device;
@@ -415,8 +415,8 @@ static struct block_device *add_partition(struct gendisk *disk, int partno,
 		kobject_uevent(&pdev->kobj, KOBJ_ADD);
 	return bdev;
 
-out_bdput:
-	bdput(bdev);
+out_iput:
+	iput(bdev->bd_inode);
 	return ERR_PTR(err);
 out_del:
 	kobject_put(bdev->bd_holder_dir);
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 5c56d88fd838..8747c264e64c 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -921,16 +921,6 @@ void bdev_add(struct block_device *bdev, dev_t dev)
 	insert_inode_hash(bdev->bd_inode);
 }
 
-static struct block_device *bdget(dev_t dev)
-{
-	struct inode *inode;
-
-	inode = ilookup(blockdev_superblock, dev);
-	if (!inode)
-		return NULL;
-	return &BDEV_I(inode)->bdev;
-}
-
 long nr_blockdev_pages(void)
 {
 	struct inode *inode;
@@ -944,12 +934,6 @@ long nr_blockdev_pages(void)
 	return ret;
 }
 
-void bdput(struct block_device *bdev)
-{
-	iput(bdev->bd_inode);
-}
-EXPORT_SYMBOL(bdput);
- 
 /**
  * bd_may_claim - test whether a block device can be claimed
  * @bdev: block device of interest
@@ -1308,18 +1292,20 @@ struct block_device *blkdev_get_no_open(dev_t dev)
 {
 	struct block_device *bdev;
 	struct gendisk *disk;
+	struct inode *inode;
 
-	bdev = bdget(dev);
-	if (!bdev) {
+	inode = ilookup(blockdev_superblock, dev);
+	if (!inode) {
 		blk_request_module(dev);
-		bdev = bdget(dev);
-		if (!bdev)
+		inode = ilookup(blockdev_superblock, dev);
+		if (!inode)
 			return NULL;
 	}
 
+	bdev = &BDEV_I(inode)->bdev;
 	disk = bdev->bd_disk;
 	if (!kobject_get_unless_zero(&disk_to_dev(disk)->kobj))
-		goto bdput;
+		goto iput;
 	if ((disk->flags & (GENHD_FL_UP | GENHD_FL_HIDDEN)) != GENHD_FL_UP)
 		goto put_disk;
 	if (!try_module_get(disk->fops->owner))
@@ -1328,14 +1314,14 @@ struct block_device *blkdev_get_no_open(dev_t dev)
 	/* switch to a device model reference instead of the inode one: */
 	if (!kobject_get_unless_zero(&bdev->bd_device.kobj))
 		goto put_module;
-	bdput(bdev);
+	iput(bdev->bd_inode);
 	return bdev;
 put_module:
 	module_put(disk->fops->owner);
 put_disk:
 	put_disk(disk);
-bdput:
-	bdput(bdev);
+iput:
+	iput(bdev->bd_inode);
 	return NULL;
 }
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 98772da38bb1..b94de1d194b8 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1984,7 +1984,6 @@ void blkdev_put_no_open(struct block_device *bdev);
 struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
 void bdev_add(struct block_device *bdev, dev_t dev);
 struct block_device *I_BDEV(struct inode *inode);
-void bdput(struct block_device *);
 int truncate_bdev_range(struct block_device *bdev, fmode_t mode, loff_t lstart,
 		loff_t lend);
 
-- 
2.30.2