missing helpers: bdev_unhash(), bdev_drop()

bdev_unhash(): make block device invisible to lookups by device number
bdev_drop(): drop reference to associated inode.

Both are internal, for use by genhd and partition-related code - similar
to bdev_add().  The logics in there (especially the lifetime-related
parts of it) ought to be cleaned up, but that's a separate story; here
we just encapsulate getting to associated inode.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 10 insertions, 0 deletions

diff --git a/block/bdev.c b/block/bdev.c
index 536233ac3e99..28e6f0423857 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -451,6 +451,16 @@ void bdev_add(struct block_device *bdev, dev_t dev)
 	insert_inode_hash(bdev->bd_inode);
 }
 
+void bdev_unhash(struct block_device *bdev)
+{
+	remove_inode_hash(bdev->bd_inode);
+}
+
+void bdev_drop(struct block_device *bdev)
+{
+	iput(bdev->bd_inode);
+}
+
 long nr_blockdev_pages(void)
 {
 	struct inode *inode;