Pull device mapper updates from Mike Snitzer: - a few conversions from atomic_t to ref_count_t - a DM core fix for a race during device destruction that could result in a BUG_ON - a stable@ fix for a DM cache race condition that could lead to data corruption when operating in writeback mode (writethrough is default) - various DM cache cleanups and improvements - add DAX support to the DM log-writes target - a fix for the DM zoned target's ability to deal with the last zone of the drive being smaller than all others - a stable@ DM crypt and DM integrity fix for a negative check that was to restrictive (prevented slab debug with XFS ontop of DM crypt from working) - a DM raid target fix for a panic that can occur when forcing a raid to sync * tag 'for-4.15/dm' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (25 commits) dm cache: lift common migration preparation code to alloc_migration() dm cache: remove usused deferred_cells member from struct cache dm cache policy smq: allocate cache blocks in order dm cache policy smq: change max background work from 10240 to 4096 blocks dm cache background tracker: limit amount of background work that may be issued at once dm cache policy smq: take origin idle status into account when queuing writebacks dm cache policy smq: handle races with queuing background_work dm raid: fix panic when attempting to force a raid to sync dm integrity: allow unaligned bv_offset dm crypt: allow unaligned bv_offset dm: small cleanup in dm_get_md() dm: fix race between dm_get_from_kobject() and __dm_destroy() dm: allocate struct mapped_device with kvzalloc dm zoned: ignore last smaller runt zone dm space map metadata: use ARRAY_SIZE dm log writes: add support for DAX dm log writes: add support for inline data buffers dm cache: simplify get_per_bio_data() by removing data_size argument dm cache: remove all obsolete writethrough-specific code dm cache: submit writethrough writes in parallel to origin and cache ...
Pull core block layer updates from Jens Axboe:
"This is the main pull request for block storage for 4.15-rc1.
Nothing out of the ordinary in here, and no API changes or anything
like that. Just various new features for drivers, core changes, etc.
In particular, this pull request contains:
- A patch series from Bart, closing the whole on blk/scsi-mq queue
quescing.
- A series from Christoph, building towards hidden gendisks (for
multipath) and ability to move bio chains around.
- NVMe
- Support for native multipath for NVMe (Christoph).
- Userspace notifications for AENs (Keith).
- Command side-effects support (Keith).
- SGL support (Chaitanya Kulkarni)
- FC fixes and improvements (James Smart)
- Lots of fixes and tweaks (Various)
- bcache
- New maintainer (Michael Lyle)
- Writeback control improvements (Michael)
- Various fixes (Coly, Elena, Eric, Liang, et al)
- lightnvm updates, mostly centered around the pblk interface
(Javier, Hans, and Rakesh).
- Removal of unused bio/bvec kmap atomic interfaces (me, Christoph)
- Writeback series that fix the much discussed hundreds of millions
of sync-all units. This goes all the way, as discussed previously
(me).
- Fix for missing wakeup on writeback timer adjustments (Yafang
Shao).
- Fix laptop mode on blk-mq (me).
- {mq,name} tupple lookup for IO schedulers, allowing us to have
alias names. This means you can use 'deadline' on both !mq and on
mq (where it's called mq-deadline). (me).
- blktrace race fix, oopsing on sg load (me).
- blk-mq optimizations (me).
- Obscure waitqueue race fix for kyber (Omar).
- NBD fixes (Josef).
- Disable writeback throttling by default on bfq, like we do on cfq
(Luca Miccio).
- Series from Ming that enable us to treat flush requests on blk-mq
like any other request. This is a really nice cleanup.
- Series from Ming that improves merging on blk-mq with schedulers,
getting us closer to flipping the switch on scsi-mq again.
- BFQ updates (Paolo).
- blk-mq atomic flags memory ordering fixes (Peter Z).
- Loop cgroup support (Shaohua).
- Lots of minor fixes from lots of different folks, both for core and
driver code"
* 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits)
nvme: fix visibility of "uuid" ns attribute
blk-mq: fixup some comment typos and lengths
ide: ide-atapi: fix compile error with defining macro DEBUG
blk-mq: improve tag waiting setup for non-shared tags
brd: remove unused brd_mutex
blk-mq: only run the hardware queue if IO is pending
block: avoid null pointer dereference on null disk
fs: guard_bio_eod() needs to consider partitions
xtensa/simdisk: fix compile error
nvme: expose subsys attribute to sysfs
nvme: create 'slaves' and 'holders' entries for hidden controllers
block: create 'slaves' and 'holders' entries for hidden gendisks
nvme: also expose the namespace identification sysfs files for mpath nodes
nvme: implement multipath access to nvme subsystems
nvme: track shared namespaces
nvme: introduce a nvme_ns_ids structure
nvme: track subsystems
block, nvme: Introduce blk_mq_req_flags_t
block, scsi: Make SCSI quiesce and resume work reliably
block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag
...
Makes dm_get_md() and dm_get_from_kobject() have similar code. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The following BUG_ON was hit when testing repeat creation and removal of
DM devices:
kernel BUG at drivers/md/dm.c:2919!
CPU: 7 PID: 750 Comm: systemd-udevd Not tainted 4.1.44
Call Trace:
[<ffffffff81649e8b>] dm_get_from_kobject+0x34/0x3a
[<ffffffff81650ef1>] dm_attr_show+0x2b/0x5e
[<ffffffff817b46d1>] ? mutex_lock+0x26/0x44
[<ffffffff811df7f5>] sysfs_kf_seq_show+0x83/0xcf
[<ffffffff811de257>] kernfs_seq_show+0x23/0x25
[<ffffffff81199118>] seq_read+0x16f/0x325
[<ffffffff811de994>] kernfs_fop_read+0x3a/0x13f
[<ffffffff8117b625>] __vfs_read+0x26/0x9d
[<ffffffff8130eb59>] ? security_file_permission+0x3c/0x44
[<ffffffff8117bdb8>] ? rw_verify_area+0x83/0xd9
[<ffffffff8117be9d>] vfs_read+0x8f/0xcf
[<ffffffff81193e34>] ? __fdget_pos+0x12/0x41
[<ffffffff8117c686>] SyS_read+0x4b/0x76
[<ffffffff817b606e>] system_call_fastpath+0x12/0x71
The bug can be easily triggered, if an extra delay (e.g. 10ms) is added
between the test of DMF_FREEING & DMF_DELETING and dm_get() in
dm_get_from_kobject().
To fix it, we need to ensure the test of DMF_FREEING & DMF_DELETING and
dm_get() are done in an atomic way, so _minor_lock is used.
The other callers of dm_get() have also been checked to be OK: some
callers invoke dm_get() under _minor_lock, some callers invoke it under
_hash_lock, and dm_start_request() invoke it after increasing
md->open_count.
Cc: stable@vger.kernel.org
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The structure srcu_struct can be very big, its size is proportional to the value CONFIG_NR_CPUS. The Fedora kernel has CONFIG_NR_CPUS 8192, the field io_barrier in the struct mapped_device has 84kB in the debugging kernel and 50kB in the non-debugging kernel. The large size may result in failure of the function kzalloc_node. In order to avoid the allocation failure, we use the function kvzalloc_node, this function falls back to vmalloc if a large contiguous chunk of memory is not available. This patch also moves the field io_barrier to the last position of struct mapped_device - the reason is that on many processor architectures, short memory offsets result in smaller code than long memory offsets - on x86-64 it reduces code size by 320 bytes. Note to stable kernel maintainers - the kernels 4.11 and older don't have the function kvzalloc_node, you can use the function vzalloc_node instead. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.
However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:
----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()
// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable table_device.count is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
We already have a queue_is_rq_based helper to check if a request_queue is request based, so we can remove the flag for it. Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
The size of struct dm_name_list is different on 32-bit and 64-bit
kernels (so "(nl + 1)" differs between 32-bit and 64-bit kernels).
This mismatch caused some harmless difference in padding when using 32-bit
or 64-bit kernel. Commit 23d70c5e52dd ("dm ioctl: report event number in
DM_LIST_DEVICES") added reporting event number in the output of
DM_LIST_DEVICES_CMD. This difference in padding makes it impossible for
userspace to determine the location of the event number (the location
would be different when running on 32-bit and 64-bit kernels).
Fix the padding by using offsetof(struct dm_name_list, name) instead of
sizeof(struct dm_name_list) to determine the location of entries.
Also, the ioctl version number is incremented to 37 so that userspace
can use the version number to determine that the event number is present
and correctly located.
In addition, a global event is now raised when a DM device is created,
removed, renamed or when table is swapped, so that the user can monitor
for device changes.
Reported-by: Eugene Syromiatnikov <esyr@redhat.com>
Fixes: 23d70c5e52dd ("dm ioctl: report event number in DM_LIST_DEVICES")
Cc: stable@vger.kernel.org # 4.13
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull device mapper updates from Mike Snitzer: - Some request-based DM core and DM multipath fixes and cleanups - Constify a few variables in DM core and DM integrity - Add bufio optimization and checksum failure accounting to DM integrity - Fix DM integrity to avoid checking integrity of failed reads - Fix DM integrity to use init_completion - A couple DM log-writes target fixes - Simplify DAX flushing by eliminating the unnecessary flush abstraction that was stood up for DM's use. * tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dax: remove the pmem_dax_ops->flush abstraction dm integrity: use init_completion instead of COMPLETION_INITIALIZER_ONSTACK dm integrity: make blk_integrity_profile structure const dm integrity: do not check integrity for failed read operations dm log writes: fix >512b sectorsize support dm log writes: don't use all the cpu while waiting to log blocks dm ioctl: constify ioctl lookup table dm: constify argument arrays dm integrity: count and display checksum failures dm integrity: optimize writing dm-bufio buffers that are partially changed dm rq: do not update rq partially in each ending bio dm rq: make dm-sq requeuing behavior consistent with dm-mq behavior dm mpath: complain about unsupported __multipath_map_bio() return values dm mpath: avoid that building with W=1 causes gcc 7 to complain about fall-through