[PATCH 29/45] block: initialize struct block_device in bdev_alloc

Christoph Hellwig
2020-11-28T22:12:08Z

Don't play tricks with slab constructors as bdev structures tends to not
get reused very much, and this makes the code a lot less error prone.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Tejun Heo <tj@kernel.org>
---
fs/block_dev.c | 22 +++++++++-------------
1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 0569f5ebeb6fd0..a5b6955a841f18 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -784,20 +784,11 @@ static void bdev_free_inode(struct inode *inode)
kmem_cache_free(bdev_cachep, BDEV_I(inode));
}

-static void init_once(void *foo)
+static void init_once(void *data)
{
- struct bdev_inode *ei = (struct bdev_inode *) foo;
- struct block_device *bdev = &ei->bdev;
+ struct bdev_inode *ei = data;

- memset(bdev, 0, sizeof(*bdev));
- mutex_init(&bdev->bd_mutex);
-#ifdef CONFIG_SYSFS
- INIT_LIST_HEAD(&bdev->bd_holder_disks);
-#endif
- bdev->bd_bdi = &noop_backing_dev_info;
inode_init_once(&ei->vfs_inode);
- /* Initialize mutex for freeze. */
- mutex_init(&bdev->bd_fsfreeze_mutex);
}

static void bdev_evict_inode(struct inode *inode)
@@ -873,12 +864,17 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
mapping_set_gfp_mask(&inode->i_data, GFP_USER);

bdev = I_BDEV(inode);
+ memset(bdev, 0, sizeof(*bdev));
+ mutex_init(&bdev->bd_mutex);
+ mutex_init(&bdev->bd_fsfreeze_mutex);
spin_lock_init(&bdev->bd_size_lock);
bdev->bd_disk = disk;
bdev->bd_partno = partno;
- bdev->bd_super = NULL;
bdev->bd_inode = inode;
- bdev->bd_part_count = 0;
+ bdev->bd_bdi = &noop_backing_dev_info;
+#ifdef CONFIG_SYSFS
+ INIT_LIST_HEAD(&bdev->bd_holder_disks);
+#endif
return bdev;
}

--
2.29.2