UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

block: store the holder kobject in bd_holder_disk 

We hold a reference to the holder kobject for each bd_holder_disk,
so to make the code a bit more robust, use a reference to it instead
of the block_device.  As long as no one clears ->bd_holder_dir in
before freeing the disk, this isn't strictly required, but it does
make the code more clear and more robust.

Orignally-From: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221115141054.1051801-10-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Yu Kuai 2022-11-15 22:10:53 +08:00 committed by Jens Axboe
parent 62f535e1f0
commit 3b3449c1e6
1 changed files with 6 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
block/holder.c
View File

@ -4,7 +4,7 @@
struct bd_holder_disk {
struct list_head list;
struct block_device *bdev;
struct kobject *holder_dir;
int refcnt;
};
@ -14,7 +14,7 @@ static struct bd_holder_disk *bd_find_holder_disk(struct block_device *bdev,
struct bd_holder_disk *holder;
list_for_each_entry(holder, &disk->slave_bdevs, list)
if (holder->bdev == bdev)
if (holder->holder_dir == bdev->bd_holder_dir)
return holder;
return NULL;
}
@ -94,8 +94,9 @@ int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk)
}
INIT_LIST_HEAD(&holder->list);
holder->bdev = bdev;
holder->refcnt = 1;
holder->holder_dir = bdev->bd_holder_dir;
ret = add_symlink(disk->slave_dir, bdev_kobj(bdev));
if (ret)
goto out_free_holder;
@ -140,8 +141,8 @@ void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk)
holder = bd_find_holder_disk(bdev, disk);
if (!WARN_ON_ONCE(holder == NULL) && !--holder->refcnt) {
del_symlink(disk->slave_dir, bdev_kobj(bdev));
del_symlink(bdev->bd_holder_dir, &disk_to_dev(disk)->kobj);
kobject_put(bdev->bd_holder_dir);
del_symlink(holder->holder_dir, &disk_to_dev(disk)->kobj);
kobject_put(holder->holder_dir);
list_del_init(&holder->list);
kfree(holder);
}