tree 2cbd9f0a9f9c0e49600c999500d7c388e6c8ec4e
parent 9a66e6bd7e9ba51d83854aaf7670014e9538e462
author Christoph Hellwig <hch@lst.de> 1620998321 +0200
committer Jens Axboe <axboe@kernel.dk> 1621519175 -0600

block: prevent block device lookups at the beginning of del_gendisk

As an artifact of how gendisk lookup used to work in earlier kernels,
GENHD_FL_UP is only cleared very late in del_gendisk, and a global lock
is used to prevent opens from succeeding while del_gendisk is tearing
down the gendisk.  Switch to clearing the flag early and under bd_mutex
so that callers can use bd_mutex to stabilize the flag, which removes
the need for the global mutex.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210514131842.1600568-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>