loop cleanups

To: Jens Axboe <axboe@xxxxxxxxx>
Subject: loop cleanups
From: Christoph Hellwig <hch@xxxxxx>
Date: Mon, 21 Jun 2021 12:15:38 +0200
Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>, linux-block@xxxxxxxxxxxxxxx

Hi Jens,

this series contains a bunch of cleanups for the loop driver,
mostly related to probing and the control device.

Follow-Ups:
- Re: loop cleanups
  - From: Tetsuo Handa
- [PATCH 9/9] loop: rewrite loop_exit using idr_for_each_entry
  - From: Christoph Hellwig
- [PATCH 8/9] loop: split loop_lookup
  - From: Christoph Hellwig
- [PATCH 7/9] loop: don't allow deleting an unspecified loop device
  - From: Christoph Hellwig
- [PATCH 6/9] loop: move loop_ctl_mutex locking into loop_add
  - From: Christoph Hellwig
- [PATCH 5/9] loop: split loop_control_ioctl
  - From: Christoph Hellwig
- [PATCH 4/9] loop: don't call loop_lookup before adding a loop device
  - From: Christoph Hellwig
- [PATCH 3/9] loop: remove the l argument to loop_add
  - From: Christoph Hellwig
- [PATCH 2/9] loop: reduce loop_ctl_mutex coverage in loop_exit
  - From: Christoph Hellwig
- [PATCH 1/9] loop: reorder loop_exit
  - From: Christoph Hellwig