c30b9787a4
BLKPG_DEL_PARTITION refuses to delete partitions that still have openers, i.e., that has an elevated @bdev->bd_openers count. If a device is claimed by setting @bdev->bd_holder and @bdev->bd_holder_ops @bdev->bd_openers and @bdev->bd_holders are incremented. @bdev->bd_openers is effectively guaranteed to be >= @bdev->bd_holders. So as long as @bdev->bd_openers isn't zero we know that this partition is still in active use and that there might still be @bdev->bd_holder and @bdev->bd_holder_ops set. The only current example is @fs_holder_ops for filesystems. But that means bdev_mark_dead() which calls into bdev->bd_holder_ops->mark_dead::fs_bdev_mark_dead() is a nop. As long as there's an elevated @bdev->bd_openers count we can't delete the partition and if there isn't an elevated @bdev->bd_openers count then there's no @bdev->bd_holder or @bdev->bd_holder_ops. So simply open-code what we need to do. This gets rid of one more instance where we acquire s_umount under @disk->open_mutex. Link: https://lore.kernel.org/r/20231016-fototermin-umriss-59f1ea6c1fe6@brauner Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231017184823.1383356-2-hch@lst.de Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.