Now that we open block devices as files we need to deal with the
realities that closing is a deferred operation. An operation on the
block device such as e.g., freeze, thaw, or removal that runs
concurrently with umount, tries to acquire a stable reference on the
holder. The holder might already be gone though. Make that reliable by
grabbing a passive reference to the holder during bdev_open() and
releasing it during bdev_release().
Fixes: f3a608827d ("bdev: open block device as files") # mainline only
Reported-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/r/ZfEQQ9jZZVes0WCZ@infradead.org
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Reported-by: https://lore.kernel.org/r/CAHj4cs8tbDwKRwfS1=DmooP73ysM__xAb2PQc6XsAmWR+VuYmg@mail.gmail.com
Link: https://lore.kernel.org/r/20240315-freibad-annehmbar-ca68c375af91@brauner
Signed-off-by: Christian Brauner <brauner@kernel.org>
We just need to use the holder to indicate whether a block device open
was exclusive or not. We did use to do that before but had to give that
up once we switched to struct bdev_handle. Before struct bdev_handle we
only stashed stuff in file->private_data if this was an exclusive open
but after struct bdev_handle we always set file->private_data to a
struct bdev_handle and so we had to use bdev_handle->mode or
bdev_handle->holder. Now that we don't use struct bdev_handle anymore we
can revert back to the old behavior.
Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-32-adbd023e19cc@kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Make it possible to detected a block device that was opened with
restricted write access based only on BLK_OPEN_WRITE and
bdev->bd_writers < 0 so we won't have to claim another FMODE_* flag.
Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-31-adbd023e19cc@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
We can always go directly via:
* I_BDEV(bdev_file->f_inode)
* I_BDEV(bdev_file->f_mapping->host)
So keeping struct bdev in struct bdev_handle is redundant.
Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-30-adbd023e19cc@kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Move both of them to the private block header. There's no caller in the
tree anymore that uses them directly.
Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-28-adbd023e19cc@kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Add two new helpers to allow opening block devices as files.
This is not the final infrastructure. This still opens the block device
before opening a struct a file. Until we have removed all references to
struct bdev_handle we can't switch the order:
* Introduce blk_to_file_flags() to translate from block specific to
flags usable to pen a new file.
* Introduce bdev_file_open_by_{dev,path}().
* Introduce temporary sb_bdev_handle() helper to retrieve a struct
bdev_handle from a block device file and update places that directly
reference struct bdev_handle to rely on it.
* Don't count block device openes against the number of open files. A
bdev_file_open_by_{dev,path}() file is never installed into any
file descriptor table.
One idea that came to mind was to use kernel_tmpfile_open() which
would require us to pass a path and it would then call do_dentry_open()
going through the regular fops->open::blkdev_open() path. But then we're
back to the problem of routing block specific flags such as
BLK_OPEN_RESTRICT_WRITES through the open path and would have to waste
FMODE_* flags every time we add a new one. With this we can avoid using
a flag bit and we have more leeway in how we open block devices from
bdev_open_by_{dev,path}().
Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-1-adbd023e19cc@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
The SLAB_MEM_SPREAD flag is already a no-op as of 6.8-rc1, remove
its usage so we can delete it from slab. No functional change.
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Link: https://lore.kernel.org/r/20240224134646.829105-1-chengming.zhou@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'vfs-6.8.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs super updates from Christian Brauner:
"This contains the super work for this cycle including the long-awaited
series by Jan to make it possible to prevent writing to mounted block
devices:
- Writing to mounted devices is dangerous and can lead to filesystem
corruption as well as crashes. Furthermore syzbot comes with more
and more involved examples how to corrupt block device under a
mounted filesystem leading to kernel crashes and reports we can do
nothing about. Add tracking of writers to each block device and a
kernel cmdline argument which controls whether other writeable
opens to block devices open with BLK_OPEN_RESTRICT_WRITES flag are
allowed.
Note that this effectively only prevents modification of the
particular block device's page cache by other writers. The actual
device content can still be modified by other means - e.g. by
issuing direct scsi commands, by doing writes through devices lower
in the storage stack (e.g. in case loop devices, DM, or MD are
involved) etc. But blocking direct modifications of the block
device page cache is enough to give filesystems a chance to perform
data validation when loading data from the underlying storage and
thus prevent kernel crashes.
Syzbot can use this cmdline argument option to avoid uninteresting
crashes. Also users whose userspace setup does not need writing to
mounted block devices can set this option for hardening. We expect
that this will be interesting to quite a few workloads.
Btrfs is currently opted out of this because they still haven't
merged patches we require for this to work from three kernel
releases ago.
- Reimplement block device freezing and thawing as holder operations
on the block device.
This allows us to extend block device freezing to all devices
associated with a superblock and not just the main device. It also
allows us to remove get_active_super() and thus another function
that scans the global list of superblocks.
Freezing via additional block devices only works if the filesystem
chooses to use @fs_holder_ops for these additional devices as well.
That currently only includes ext4 and xfs.
Earlier releases switched get_tree_bdev() and mount_bdev() to use
@fs_holder_ops. The remaining nilfs2 open-coded version of
mount_bdev() has been converted to rely on @fs_holder_ops as well.
So block device freezing for the main block device will continue to
work as before.
There should be no regressions in functionality. The only special
case is btrfs where block device freezing for the main block device
never worked because sb->s_bdev isn't set. Block device freezing
for btrfs can be fixed once they can switch to @fs_holder_ops but
that can happen whenever they're ready"
* tag 'vfs-6.8.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits)
block: Fix a memory leak in bdev_open_by_dev()
super: don't bother with WARN_ON_ONCE()
super: massage wait event mechanism
ext4: Block writes to journal device
xfs: Block writes to log device
fs: Block writes to mounted block devices
btrfs: Do not restrict writes to btrfs devices
block: Add config option to not allow writing to mounted devices
block: Remove blkdev_get_by_*() functions
bcachefs: Convert to bdev_open_by_path()
fs: handle freezing from multiple devices
fs: remove dead check
nilfs2: simplify device handling
fs: streamline thaw_super_locked
ext4: simplify device handling
xfs: simplify device handling
fs: simplify setup_bdev_super() calls
blkdev: comment fs_holder_ops
porting: document block device freeze and thaw changes
fs: remove unused helper
...
Propagate the per-queue stable_write flags into each bdev inode in bdev_add.
This makes sure devices that require stable writes have it set for I/O
on the block device node as well.
Note that this doesn't cover the case of a flag changing on a live device
yet. We should handle that as well, but I plan to cover it as part of a
more general rework of how changing runtime paramters on block devices
works.
Fixes: 1cb039f3dc ("bdi: replace BDI_CAP_STABLE_WRITES with a queue and a sb flag")
Reported-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231025141020.192413-3-hch@lst.de
Tested-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Writing to mounted devices is dangerous and can lead to filesystem
corruption as well as crashes. Furthermore syzbot comes with more and
more involved examples how to corrupt block device under a mounted
filesystem leading to kernel crashes and reports we can do nothing
about. Add tracking of writers to each block device and a kernel cmdline
argument which controls whether other writeable opens to block devices
open with BLK_OPEN_RESTRICT_WRITES flag are allowed. We will make
filesystems use this flag for used devices.
Note that this effectively only prevents modification of the particular
block device's page cache by other writers. The actual device content
can still be modified by other means - e.g. by issuing direct scsi
commands, by doing writes through devices lower in the storage stack
(e.g. in case loop devices, DM, or MD are involved) etc. But blocking
direct modifications of the block device page cache is enough to give
filesystems a chance to perform data validation when loading data from
the underlying storage and thus prevent kernel crashes.
Syzbot can use this cmdline argument option to avoid uninteresting
crashes. Also users whose userspace setup does not need writing to
mounted block devices can set this option for hardening.
Link: https://lore.kernel.org/all/60788e5d-5c7c-1142-e554-c21d709acfd9@linaro.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20231101174325.10596-3-jack@suse.cz
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
blkdev_get_by_*() and blkdev_put() functions are now unused. Remove
them.
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20231101174325.10596-2-jack@suse.cz
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The old method of implementing block device freeze and thaw operations
required us to rely on get_active_super() to walk the list of all
superblocks on the system to find any superblock that might use the
block device. This is wasteful and not very pleasant overall.
Now that we can finally go straight from block device to owning
superblock things become way simpler.
Link: https://lore.kernel.org/r/20231024-vfs-super-freeze-v2-5-599c19f4faac@kernel.org
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
When freeze_super() is called, sync_filesystem() will be called which
calls sync_blockdev() and already surfaces any errors. Do the same for
block devices that aren't owned by a superblock and also for filesystems
that don't call sync_blockdev() internally but implicitly rely on
bdev_freeze() to do it.
Link: https://lore.kernel.org/r/20231024-vfs-super-freeze-v2-3-599c19f4faac@kernel.org
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
We have bdev_mark_dead() etc and we're going to move block device
freezing to holder ops in the next patch. Make the naming consistent:
* freeze_bdev() -> bdev_freeze()
* thaw_bdev() -> bdev_thaw()
Also document the return code.
Link: https://lore.kernel.org/r/20231024-vfs-super-freeze-v2-2-599c19f4faac@kernel.org
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
there's little I can say which isn't in the individual changelogs.
The lengthier patch series are
- "kdump: use generic functions to simplify crashkernel reservation in
arch", from Baoquan He. This is mainly cleanups and consolidation of
the "crashkernel=" kernel parameter handling.
- After much discussion, David Laight's "minmax: Relax type checks in
min() and max()" is here. Hopefully reduces some typecasting and the
use of min_t() and max_t().
- A group of patches from Oleg Nesterov which clean up and slightly fix
our handling of reads from /proc/PID/task/... and which remove
task_struct.therad_group.
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Merge tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
"As usual, lots of singleton and doubleton patches all over the tree
and there's little I can say which isn't in the individual changelogs.
The lengthier patch series are
- 'kdump: use generic functions to simplify crashkernel reservation
in arch', from Baoquan He. This is mainly cleanups and
consolidation of the 'crashkernel=' kernel parameter handling
- After much discussion, David Laight's 'minmax: Relax type checks in
min() and max()' is here. Hopefully reduces some typecasting and
the use of min_t() and max_t()
- A group of patches from Oleg Nesterov which clean up and slightly
fix our handling of reads from /proc/PID/task/... and which remove
task_struct.thread_group"
* tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (64 commits)
scripts/gdb/vmalloc: disable on no-MMU
scripts/gdb: fix usage of MOD_TEXT not defined when CONFIG_MODULES=n
.mailmap: add address mapping for Tomeu Vizoso
mailmap: update email address for Claudiu Beznea
tools/testing/selftests/mm/run_vmtests.sh: lower the ptrace permissions
.mailmap: map Benjamin Poirier's address
scripts/gdb: add lx_current support for riscv
ocfs2: fix a spelling typo in comment
proc: test ProtectionKey in proc-empty-vm test
proc: fix proc-empty-vm test with vsyscall
fs/proc/base.c: remove unneeded semicolon
do_io_accounting: use sig->stats_lock
do_io_accounting: use __for_each_thread()
ocfs2: replace BUG_ON() at ocfs2_num_free_extents() with ocfs2_error()
ocfs2: fix a typo in a comment
scripts/show_delta: add __main__ judgement before main code
treewide: mark stuff as __ro_after_init
fs: ocfs2: check status values
proc: test /proc/${pid}/statm
compiler.h: move __is_constexpr() to compiler.h
...
disk_check_media_change is mostly called from ->open where it makes
little sense to mark the file system on the device as dead, as we
are just opening it. So instead of calling bdev_mark_dead from
disk_check_media_change move it into the few callers that are not
in an open instance. This avoid calling into bdev_mark_dead and
thus taking s_umount with open_mutex held.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231017184823.1383356-4-hch@lst.de
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The implementation of bdev holder operations such as fs_bdev_mark_dead()
and fs_bdev_sync() grab sb->s_umount semaphore under
bdev->bd_holder_lock. This is problematic because it leads to
disk->open_mutex -> sb->s_umount lock ordering which is counterintuitive
(usually we grab higher level (e.g. filesystem) locks first and lower
level (e.g. block layer) locks later) and indeed makes lockdep complain
about possible locking cycles whenever we open a block device while
holding sb->s_umount semaphore. Implement a function
bdev_super_lock_shared() which safely transitions from holding
bdev->bd_holder_lock to holding sb->s_umount on alive superblock without
introducing the problematic lock dependency. We use this function
fs_bdev_sync() and fs_bdev_mark_dead().
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20231018152924.3858-1-jack@suse.cz
Link: https://lore.kernel.org/r/20231017184823.1383356-1-hch@lst.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Convert blkdev_open() to use bdev_open_by_dev(). To be able to propagate
handle from blkdev_open() to blkdev_release() we need to stop using
existence of file->private_data to determine exclusive block device
opens. Use bdev_handle->mode for this purpose since file->f_flags
isn't usable for this (O_EXCL is cleared from the flags during open).
Acked-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230927093442.25915-2-jack@suse.cz
Signed-off-by: Christian Brauner <brauner@kernel.org>
Create struct bdev_handle that contains all parameters that need to be
passed to blkdev_put() and provide bdev_open_* functions that return
this structure instead of plain bdev pointer. This will eventually allow
us to pass one more argument to blkdev_put() (renamed to bdev_release())
without too much hassle.
Acked-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230927093442.25915-1-jack@suse.cz
Signed-off-by: Christian Brauner <brauner@kernel.org>
__read_mostly predates __ro_after_init. Many variables which are marked
__read_mostly should have been __ro_after_init from day 1.
Also, mark some stuff as "const" and "__init" while I'm at it.
[akpm@linux-foundation.org: revert sysctl_nr_open_min, sysctl_nr_open_max changes due to arm warning]
[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/4f6bb9c0-abba-4ee4-a7aa-89265e886817@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Allow the kernel to initiate a freeze of a filesystem. The kernel
and userspace can both hold a freeze on a filesystem at the same
time; the freeze is not lifted until /both/ holders lift it. This
will enable us to fix a longstanding bug in XFS online fsck.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
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Merge tag 'vfs-6.6-merge-2' of ssh://gitolite.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull filesystem freezing updates from Darrick Wong:
New code for 6.6:
* Allow the kernel to initiate a freeze of a filesystem. The kernel
and userspace can both hold a freeze on a filesystem at the same
time; the freeze is not lifted until /both/ holders lift it. This
will enable us to fix a longstanding bug in XFS online fsck.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Message-Id: <20230822182604.GB11286@frogsfrogsfrogs>
Signed-off-by: Christian Brauner <brauner@kernel.org>
BLKFLSBUF is a historic ioctl that is called on a file handle to a
block device and syncs either the file system mounted on that block
device if there is one, or otherwise the just the data on the block
device.
Replace the get_super based syncing with a holder operation to remove
the last usage of get_super, and to also support syncing the file system
if the block device is not the main block device stored in s_dev.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Message-Id: <20230811100828.1897174-16-hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Combine the newly merged bdev_mark_dead helper with the existing
mark_dead holder operation so that all operations that invalidate
a device that is dead or being removed now go through the holder
ops. This allows file systems to explicitly shutdown either ASAP
(for a surprise removal) or after writing back data (for an orderly
removal), and do so not only for the main device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Message-Id: <20230811100828.1897174-15-hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
We currently have two interfaces that take a block_devices and the find
a mounted file systems to flush or invaldidate data on it. Both are a
bit problematic because they only work for the "main" block devices
that is used as s_dev for the super_block, and because they don't call
into the file system at all.
Merge the two into a new bdev_mark_dead helper that does both the
syncing and invalidation and which is properly documented. This is
in preparation of merging the functionality into the ->mark_dead
holder operation so that it will work on additional block devices
used by a file systems and give us a single entry point for invalidation
of dead devices or media.
Note that a single standalone fsync_bdev call for an obscure ioctl
remains for now, but that one will also be deal with in a bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Message-Id: <20230811100828.1897174-14-hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Userspace can freeze a filesystem using the FIFREEZE ioctl or by
suspending the block device; this state persists until userspace thaws
the filesystem with the FITHAW ioctl or resuming the block device.
Since commit 18e9e5104f ("Introduce freeze_super and thaw_super for
the fsfreeze ioctl") we only allow the first freeze command to succeed.
The kernel may decide that it is necessary to freeze a filesystem for
its own internal purposes, such as suspends in progress, filesystem fsck
activities, or quiescing a device prior to removal. Userspace thaw
commands must never break a kernel freeze, and kernel thaw commands
shouldn't undo userspace's freeze command.
Introduce a couple of freeze holder flags and wire it into the
sb_writers state. One kernel and one userspace freeze are allowed to
coexist at the same time; the filesystem will not thaw until both are
lifted.
I wonder if the f2fs/gfs2 code should be using a kernel freeze here, but
for now we'll use FREEZE_HOLDER_USERSPACE to preserve existing
behaviors.
Cc: mcgrof@kernel.org
Cc: jack@suse.cz
Cc: hch@infradead.org
Cc: ruansy.fnst@fujitsu.com
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Fix the documentation of the devt_from_partuuid() return value.
Fix the following two recently introduced kernel-doc warnings:
block/bdev.c:570: warning: Function parameter or member 'hops' not described in 'bd_finish_claiming'
block/early-lookup.c:46: warning: Function parameter or member 'devt' not described in 'devt_from_partuuid'
Cc: Christoph Hellwig <hch@lst.de>
Fixes: 0718afd47f ("block: introduce holder ops")
Fixes: cf056a4312 ("init: improve the name_to_dev_t interface")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230621165054.743815-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The only overlap between the block open flags mapped into the fmode_t and
other uses of fmode_t are FMODE_READ and FMODE_WRITE. Define a new
blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and
->ioctl and stop abusing fmode_t.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The current interface for exclusive opens is rather confusing as it
requires both the FMODE_EXCL flag and a holder. Remove the need to pass
FMODE_EXCL and just key off the exclusive open off a non-NULL holder.
For blkdev_put this requires adding the holder argument, which provides
better debug checking that only the holder actually releases the hold,
but at the same time allows removing the now superfluous mode argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The mode argument to the ->release block_device_operation is never used,
so remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
->open is only called on the whole device. Make that explicit by
passing a gendisk instead of the block_device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For whole devices ->open is called for each open, but for partitions it
is only called on the first open of a partition, e.g.:
open("/dev/vdb", ...)
open("/dev/vdb", ...)
- 2 call to ->open
open("/dev/vdb1", ...)
open("/dev/vdb", ...)
- 2 call to ->open
open("/dev/vdb", ...)
open("/dev/vdb", ...)
- just open call to ->open
This is problematic as various block drivers look at open flags and
might not do all the required setup if the earlier open was with an
odd flag like O_NDELAY or the magic 3 ioctl-only open mode.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Phillip Potter <phil@philpotter.co.uk>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a new blk_holder_ops structure, which is passed to blkdev_get_by_* and
installed in the block_device for exclusive claims. It will be used to
allow the block layer to call back into the user of the block device for
thing like notification of a removed device or a device resize.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20230601094459.1350643-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no reason for this lock to spin, and being able to sleep under
it will come in handy soon.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20230601094459.1350643-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The long if/else chain obsfucates the actual logic. Tidy it up to be
more structured. Also drop the whole argument, as it can be trivially
derived from bdev using bdev_whole, and having the bdev_whole in the
function makes it easier to follow.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20230601094459.1350643-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move all the logic to release an exclusive claim into a helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20230601094459.1350643-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The code for setting a block device capacity (bd_nr_sectors field of
struct block_device) is duplicated in set_capacity() and
bdev_set_nr_sectors(). Clean this up by making bdev_set_nr_sectors()
a block layer internal function defined in block/bdev.c instead of
having this function statically defined in block/partitions/core.c.
With this change, set_capacity() implementation can be simplified to
only calling bdev_set_nr_sectors().
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230424131318.79935-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have a long chain of memory dereferencing just to whether or not
this disk has a special submit_bio helper. As that's not necessarily
the common case, add a bd_has_submit_bio state in the bdev to avoid
traversing this memory dependency chain if we don't need to.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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>
Use only one hyphen in kernel-doc notation between the function name
and its short description.
The is the documented kerenl-doc format. It also fixes the HTML
presentation to be consistent with other functions.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Link: https://lore.kernel.org/r/20221201070331.25685-1-rdunlap@infradead.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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
Just use the %pg format specifier instead. Also reformat the
printk statement to be more readable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20220713055317.1888500-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- 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.
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Merge tag 'exfat-for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat
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
sync_blockdev_range() is to support syncing multiple sectors
with as few block device requests as possible, it is helpful
to make the block device to give full play to its performance.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
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>
