linux/block/partitions
Christian Brauner 51b4cb4f3e
block: WARN_ON_ONCE() when we remove active partitions
The logic for disk->open_partitions is:

blkdev_get_by_*()
-> bdev_is_partition()
   -> blkdev_get_part()
      -> blkdev_get_whole() // bdev_whole->bd_openers++
      -> if (part->bd_openers == 0)
                 disk->open_partitions++
         part->bd_openers

In other words, when we first claim/open a partition we increment
disk->open_partitions and only when all part->bd_openers are closed will
disk->open_partitions be zero. That should mean that
disk->open_partitions is always > 0 as long as there's anyone that
has an open partition.

So the check for disk->open_partitions should mean that we can never
remove an active partition that has a holder and holder ops set. Assert
that in the code. The main disk isn't removed so that check doesn't work
for disk->part0 which is what we want. After all we only care about
partition not about the main disk.

Link: https://lore.kernel.org/r/20231017184823.1383356-3-hch@lst.de
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-28 13:29:22 +02:00
..
acorn.c block/partitions/acorn: Remove redundant assignments 2022-04-23 07:15:26 -06:00
aix.c block: store a gendisk in struct parsed_partitions 2021-08-12 10:31:35 -06:00
amiga.c block/partition: fix signedness issue for Amiga partitions 2023-07-05 16:34:56 -06:00
atari.c block/partitions/atari: Remove redundant assignment 2022-04-23 07:15:26 -06:00
atari.h block: declare all partition detection routines in check.h 2020-03-24 07:57:08 -06:00
check.h block: Convert read_part_sector() to use a folio 2022-08-02 12:34:03 -04:00
cmdline.c block: use strscpy() to instead of strncpy() 2023-08-22 18:07:50 -06:00
core.c block: WARN_ON_ONCE() when we remove active partitions 2023-10-28 13:29:22 +02:00
efi.c partitions/efi: use bdev_nr_bytes instead of open coding it 2021-10-19 06:16:50 -06:00
efi.h block: remove genhd.h 2022-02-02 07:49:59 -07:00
ibm.c partitions/ibm: use bdev_nr_sectors instead of open coding it 2021-10-19 06:17:33 -06:00
karma.c block: remove block/partitions/karma.h 2020-03-24 07:57:08 -06:00
Kconfig block: move menu "Partition type" to block/partitions/Kconfig 2021-10-18 06:17:35 -06:00
ldm.c block/partitions/ldm: Remove redundant assignments 2022-04-23 07:15:26 -06:00
ldm.h block: remove genhd.h 2022-02-02 07:49:59 -07:00
mac.c block: store a gendisk in struct parsed_partitions 2021-08-12 10:31:35 -06:00
mac.h block: declare all partition detection routines in check.h 2020-03-24 07:57:08 -06:00
Makefile block: merge partition-generic.c and check.c 2020-03-24 07:57:08 -06:00
msdos.c block: store a gendisk in struct parsed_partitions 2021-08-12 10:31:35 -06:00
osf.c block: remove block/partitions/osf.h 2020-03-24 07:57:08 -06:00
sgi.c block: store a gendisk in struct parsed_partitions 2021-08-12 10:31:35 -06:00
sun.c block: store a gendisk in struct parsed_partitions 2021-08-12 10:31:35 -06:00
sysv68.c block: declare all partition detection routines in check.h 2020-03-24 07:57:08 -06:00
ultrix.c block: declare all partition detection routines in check.h 2020-03-24 07:57:08 -06:00