The ->rw_page method is a special purpose bypass of the usual bio handling
path that is limited to single-page reads and writes and synchronous which
causes a lot of extra code in the drivers, callers and the block layer.
The only remaining user is the MM swap code. Switch that swap code to
simply submit a single-vec on-stack bio an synchronously wait on it based
on a newly added QUEUE_FLAG_SYNCHRONOUS flag set by the drivers that
currently implement ->rw_page instead. While this touches one extra cache
line and executes extra code, it simplifies the block layer and drivers
and ensures that all feastures are properly supported by all drivers, e.g.
right now ->rw_page bypassed cgroup writeback entirely.
[akpm@linux-foundation.org: fix comment typo, per Dan]
Link: https://lkml.kernel.org/r/20230125133436.447864-8-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add support for STATX_DIOALIGN to block devices, so that direct I/O
alignment restrictions are exposed to userspace in a generic way.
Note that this breaks the tradition of stat operating only on the block
device node, not the block device itself. However, it was felt that
doing this is preferable, in order to make the interface useful and
avoid needing separate interfaces for regular files and block devices.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Link: https://lore.kernel.org/r/20220827065851.135710-3-ebiggers@kernel.org
Pull exfat updates from Namjae Jeon:
- fix referencing wrong parent directory information during rename
- introduce a sys_tz mount option to use system timezone
- improve performance while zeroing a cluster with dirsync mount option
- fix slab-out-bounds in exat_clear_bitmap() reported from syzbot
* tag 'exfat-for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
exfat: check if cluster num is valid
exfat: reduce block requests when zeroing a cluster
block: add sync_blockdev_range()
exfat: introduce mount option 'sys_tz'
exfat: fix referencing wrong parent directory information after renaming
All manipulation of bd_openers is under disk->open_mutex and will remain
so for the foreseeable future. But at least one place reads it without
the lock (blkdev_get) and there are more to be added. So make sure the
compiler does not do turn the increments and decrements into non-atomic
sequences by using an atomic_t.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220330052917.2566582-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
As Luis reported, losetup currently doesn't properly create the loop
device without this if the device node already exists because old
scripts created it manually. So default to y for now and remove the
aggressive removal schedule.
Reported-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220225181440.1351591-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
disk->fops->owner is grabbed in blkdev_get_no_open() after the disk
kobject refcount is increased. This way can't make sure that
disk->fops->owner is still alive since del_gendisk() still can move
on if the kobject refcount of disk is grabbed by open() and
disk->fops->open() isn't called yet.
Fixes the issue by moving try_module_get() into blkdev_get_by_dev()
with ->open_mutex() held, then we can drain the in-progress open()
in del_gendisk(). Meantime new open() won't succeed because disk
becomes not alive.
This way is reasonable because blkdev_get_no_open() needn't to touch
disk->fops or defined callbacks.
Cc: Christoph Hellwig <hch@lst.de>
Cc: czhong@redhat.com
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211111020343.316126-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
