Make sure ->dax_dev is NULL on error so that the cleanup path doesn't
trip over an ERR_PTR.
Reported-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211129102203.2243509-2-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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Merge tag 'for-5.16/block-2021-11-09' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
- Set of fixes for the batched tag allocation (Ming, me)
- add_disk() error handling fix (Luis)
- Nested queue quiesce fixes (Ming)
- Shared tags init error handling fix (Ye)
- Misc cleanups (Jean, Ming, me)
* tag 'for-5.16/block-2021-11-09' of git://git.kernel.dk/linux-block:
nvme: wait until quiesce is done
scsi: make sure that request queue queiesce and unquiesce balanced
scsi: avoid to quiesce sdev->request_queue two times
blk-mq: add one API for waiting until quiesce is done
blk-mq: don't free tags if the tag_set is used by other device in queue initialztion
block: fix device_add_disk() kobject_create_and_add() error handling
block: ensure cached plug request matches the current queue
block: move queue enter logic into blk_mq_submit_bio()
block: make bio_queue_enter() fast-path available inline
block: split request allocation components into helpers
block: have plug stored requests hold references to the queue
blk-mq: update hctx->nr_active in blk_mq_end_request_batch()
blk-mq: add RQF_ELV debug entry
blk-mq: only try to run plug merge if request has same queue with incoming bio
block: move RQF_ELV setting into allocators
dm: don't stop request queue after the dm device is suspended
block: replace always false argument with 'false'
block: assign correct tag before doing prefetch of request
blk-mq: fix redundant check of !e expression
subsystem. Also enhance both the integrity and crypt targets to emit
events to via dm-audit.
- Various other simple code improvements and cleanups.
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Merge tag 'for-5.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- Add DM core support for emitting audit events through the audit
subsystem. Also enhance both the integrity and crypt targets to emit
events to via dm-audit.
- Various other simple code improvements and cleanups.
* tag 'for-5.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm table: log table creation error code
dm: make workqueue names device-specific
dm writecache: Make use of the helper macro kthread_run()
dm crypt: Make use of the helper macro kthread_run()
dm verity: use bvec_kmap_local in verity_for_bv_block
dm log writes: use memcpy_from_bvec in log_writes_map
dm integrity: use bvec_kmap_local in __journal_read_write
dm integrity: use bvec_kmap_local in integrity_metadata
dm: add add_disk() error handling
dm: Remove redundant flush_workqueue() calls
dm crypt: log aead integrity violations to audit subsystem
dm integrity: log audit events for dm-integrity target
dm: introduce audit event module for device mapper
For fixing queue quiesce race between driver and block layer(elevator
switch, update nr_requests, ...), we need to support concurrent quiesce
and unquiesce, which requires the two call to be balanced.
__bind() is only called from dm_swap_table() in which dm device has been
suspended already, so not necessary to stop queue again. With this way,
request queue quiesce and unquiesce can be balanced.
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Fixes: e70feb8b3e ("blk-mq: support concurrent queue quiesce/unquiesce")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Link: https://lore.kernel.org/r/20211021145918.2691762-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We never checked for errors on add_disk() as this function returned
void. Now that this is fixed, use the shiny new error handling.
There are two calls to dm_setup_md_queue() which can fail then, one on
dm_early_create() and we can easily see that the error path there
calls dm_destroy in the error path. The other use case is on the ioctl
table_load case. If that fails userspace needs to call the
DM_DEV_REMOVE_CMD to cleanup the state - similar to any other
failure.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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Merge tag 'for-5.16/drivers-2021-10-29' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
- paride driver cleanups (Christoph)
- Remove cryptoloop support (Christoph)
- null_blk poll support (me)
- Now that add_disk() supports proper error handling, add it to various
drivers (Luis)
- Make ataflop actually work again (Michael)
- s390 dasd fixes (Stefan, Heiko)
- nbd fixes (Yu, Ye)
- Remove redundant wq flush in mtip32xx (Christophe)
- NVMe updates
- fix a multipath partition scanning deadlock (Hannes Reinecke)
- generate uevent once a multipath namespace is operational again
(Hannes Reinecke)
- support unique discovery controller NQNs (Hannes Reinecke)
- fix use-after-free when a port is removed (Israel Rukshin)
- clear shadow doorbell memory on resets (Keith Busch)
- use struct_size (Len Baker)
- add error handling support for add_disk (Luis Chamberlain)
- limit the maximal queue size for RDMA controllers (Max Gurtovoy)
- use a few more symbolic names (Max Gurtovoy)
- fix error code in nvme_rdma_setup_ctrl (Max Gurtovoy)
- add support for ->map_queues on FC (Saurav Kashyap)
- support the current discovery subsystem entry (Hannes Reinecke)
- use flex_array_size and struct_size (Len Baker)
- bcache fixes (Christoph, Coly, Chao, Lin, Qing)
- MD updates (Christoph, Guoqing, Xiao)
- Misc fixes (Dan, Ding, Jiapeng, Shin'ichiro, Ye)
* tag 'for-5.16/drivers-2021-10-29' of git://git.kernel.dk/linux-block: (117 commits)
null_blk: Fix handling of submit_queues and poll_queues attributes
block: ataflop: Fix warning comparing pointer to 0
bcache: replace snprintf in show functions with sysfs_emit
bcache: move uapi header bcache.h to bcache code directory
nvmet: use flex_array_size and struct_size
nvmet: register discovery subsystem as 'current'
nvmet: switch check for subsystem type
nvme: add new discovery log page entry definitions
block: ataflop: more blk-mq refactoring fixes
block: remove support for cryptoloop and the xor transfer
mtd: add add_disk() error handling
rnbd: add error handling support for add_disk()
um/drivers/ubd_kern: add error handling support for add_disk()
m68k/emu/nfblock: add error handling support for add_disk()
xen-blkfront: add error handling support for add_disk()
bcache: add error handling support for add_disk()
dm: add add_disk() error handling
block: aoe: fixup coccinelle warnings
nvmet: use struct_size over open coded arithmetic
nvme: drop scan_lock and always kick requeue list when removing namespaces
...
blk_keyslot_manager is misnamed because it doesn't necessarily manage
keyslots. It actually does several different things:
- Contains the crypto capabilities of the device.
- Provides functions to control the inline encryption hardware.
Originally these were just for programming/evicting keyslots;
however, new functionality (hardware-wrapped keys) will require new
functions here which are unrelated to keyslots. Moreover,
device-mapper devices already (ab)use "keyslot_evict" to pass key
eviction requests to their underlying devices even though
device-mapper devices don't have any keyslots themselves (so it
really should be "evict_key", not "keyslot_evict").
- Sometimes (but not always!) it manages keyslots. Originally it
always did, but device-mapper devices don't have keyslots
themselves, so they use a "passthrough keyslot manager" which
doesn't actually manage keyslots. This hack works, but the
terminology is unnatural. Also, some hardware doesn't have keyslots
and thus also uses a "passthrough keyslot manager" (support for such
hardware is yet to be upstreamed, but it will happen eventually).
Let's stop having keyslot managers which don't actually manage keyslots.
Instead, rename blk_keyslot_manager to blk_crypto_profile.
This is a fairly big change, since for consistency it also has to update
keyslot manager-related function names, variable names, and comments --
not just the actual struct name. However it's still a fairly
straightforward change, as it doesn't change any actual functionality.
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20211018180453.40441-4-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation for renaming struct blk_keyslot_manager to struct
blk_crypto_profile, rename the keyslot-manager.h and keyslot-manager.c
source files. Renaming these files separately before making a lot of
changes to their contents makes it easier for git to understand that
they were renamed.
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20211018180453.40441-3-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.
There are two calls to dm_setup_md_queue() which can fail then,
one on dm_early_create() and we can easily see that the error path
there calls dm_destroy in the error path. The other use case is on
the ioctl table_load case. If that fails userspace needs to call
the DM_DEV_REMOVE_CMD to cleanup the state - similar to any other
failure.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20211015233028.2167651-4-mcgrof@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.
Polling for the bio itself leads to a few advantages:
- the cookie construction can made entirely private in blk-mq.c
- the caller does not need to remember the request_queue and cookie
separately and thus sidesteps their lifetime issues
- keeping the device and the cookie inside the bio allows to trivially
support polling BIOs remapping by stacking drivers
- a lot of code to propagate the cookie back up the submission path can
be removed entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- Fix a race condition in the teardown path of raw mode pmem namespaces.
- Cleanup the code that filesystems use to detect filesystem-dax
capabilities of their underlying block device.
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Merge tag 'libnvdimm-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
- Fix a race condition in the teardown path of raw mode pmem
namespaces.
- Cleanup the code that filesystems use to detect filesystem-dax
capabilities of their underlying block device.
* tag 'libnvdimm-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
dax: remove bdev_dax_supported
xfs: factor out a xfs_buftarg_is_dax helper
dax: stub out dax_supported for !CONFIG_FS_DAX
dax: remove __generic_fsdax_supported
dax: move the dax_read_lock() locking into dax_supported
dax: mark dax_get_by_host static
dm: use fs_dax_get_by_bdev instead of dax_get_by_host
dax: stop using bdevname
fsdax: improve the FS_DAX Kconfig description and help text
libnvdimm/pmem: Fix crash triggered when I/O in-flight during unbind
There is no point in trying to finding the dax device if the DAX flag is
not set on the queue as none of the users of the device mapper exported
block devices could make use of the DAX capability.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20210826135510.6293-4-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The end-users of DM devices/targets may remove and re-create the same
device multiple times. IMA does not measure such duplicate events if the
configuration CONFIG_IMA_DISABLE_HTABLE is set to 'n'.
To avoid confusion, the end-users need some indication on the client
if that configuration option is disabled.
Add a one-time warning during dm_init() if CONFIG_IMA_DISABLE_HTABLE
is set to 'n', to notify the end-users that duplicate events will not
be measured in the ima log. Also cleanup some whitespace in dm_init().
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
DM configures a block device with various target specific attributes
passed to it as a table. DM loads the table, and calls each target’s
respective constructors with the attributes as input parameters.
Some of these attributes are critical to ensure the device meets
certain security bar. Thus, IMA should measure these attributes, to
ensure they are not tampered with, during the lifetime of the device.
So that the external services can have high confidence in the
configuration of the block-devices on a given system.
Some devices may have large tables. And a given device may change its
state (table-load, suspend, resume, rename, remove, table-clear etc.)
many times. Measuring these attributes each time when the device
changes its state will significantly increase the size of the IMA logs.
Further, once configured, these attributes are not expected to change
unless a new table is loaded, or a device is removed and recreated.
Therefore the clear-text of the attributes should only be measured
during table load, and the hash of the active/inactive table should be
measured for the remaining device state changes.
Export IMA function ima_measure_critical_data() to allow measurement
of DM device parameters, as well as target specific attributes, during
table load. Compute the hash of the inactive table and store it for
measurements during future state change. If a load is called multiple
times, update the inactive table hash with the hash of the latest
populated table. So that the correct inactive table hash is measured
when the device transitions to different states like resume, remove,
rename, etc.
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com> # leak fix
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
device mapper is currently the only outlier that tries to call
register_disk after add_disk, leading to fairly inconsistent state
of these block layer data structures. Instead change device-mapper
to just register the gendisk later now that the holder mechanism
can cope with that.
Note that this introduces a user visible change: the dm kobject is
now only visible after the initial table has been loaded.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20210804094147.459763-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move setting md->type from both callers into dm_setup_md_queue.
This ensures that md->type is only set to a valid value after the queue
has been fully setup, something we'll rely on future changes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20210804094147.459763-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
md->queue is now always set when md->disk is set, so simplify the
conditionals a bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20210804094147.459763-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
benefit both the DM thinp and cache targets.
- A few small DM kcopyd efficiency improvements.
- Significant zoned related block core, DM core and DM zoned target
changes that culminate with adding zoned append emulation (which is
required to properly fix DM crypt's zoned support).
- Various DM writecache target changes that improve efficiency. Adds
an optional "metadata_only" feature that only promotes bios flagged
with REQ_META. But the most significant improvement is writecache's
ability to pause writeback, for a confiurable time, if/when the
working set is larger than the cache (and the cache is full) -- this
ensures performance is no worse than the slower origin device.
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Merge tag 'for-5.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- Various DM persistent-data library improvements and fixes that
benefit both the DM thinp and cache targets.
- A few small DM kcopyd efficiency improvements.
- Significant zoned related block core, DM core and DM zoned target
changes that culminate with adding zoned append emulation (which is
required to properly fix DM crypt's zoned support).
- Various DM writecache target changes that improve efficiency. Adds an
optional "metadata_only" feature that only promotes bios flagged with
REQ_META. But the most significant improvement is writecache's
ability to pause writeback, for a confiurable time, if/when the
working set is larger than the cache (and the cache is full) -- this
ensures performance is no worse than the slower origin device.
* tag 'for-5.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits)
dm writecache: make writeback pause configurable
dm writecache: pause writeback if cache full and origin being written directly
dm io tracker: factor out IO tracker
dm btree remove: assign new_root only when removal succeeds
dm zone: fix dm_revalidate_zones() memory allocation
dm ps io affinity: remove redundant continue statement
dm writecache: add optional "metadata_only" parameter
dm writecache: add "cleaner" and "max_age" to Documentation
dm writecache: write at least 4k when committing
dm writecache: flush origin device when writing and cache is full
dm writecache: have ssd writeback wait if the kcopyd workqueue is busy
dm writecache: use list_move instead of list_del/list_add in writecache_writeback()
dm writecache: commit just one block, not a full page
dm writecache: remove unused gfp_t argument from wc_add_block()
dm crypt: Fix zoned block device support
dm: introduce zone append emulation
dm: rearrange core declarations for extended use from dm-zone.c
block: introduce BIO_ZONE_WRITE_LOCKED bio flag
block: introduce bio zone helpers
block: improve handling of all zones reset operation
...
Change the type and name of task_struct::state. Drop the volatile and
shrink it to an 'unsigned int'. Rename it in order to find all uses
such that we can use READ_ONCE/WRITE_ONCE as appropriate.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20210611082838.550736351@infradead.org
For zoned targets that cannot support zone append operations, implement
an emulation using regular write operations. If the original BIO
submitted by the user is a zone append operation, change its clone into
a regular write operation directed at the target zone write pointer
position.
To do so, an array of write pointer offsets (write pointer position
relative to the start of a zone) is added to struct mapped_device. All
operations that modify a sequential zone write pointer (writes, zone
reset, zone finish and zone append) are intersepted in __map_bio() and
processed using the new functions dm_zone_map_bio().
Detection of the target ability to natively support zone append
operations is done from dm_table_set_restrictions() by calling the
function dm_set_zones_restrictions(). A target that does not support
zone append operation, either by explicitly declaring it using the new
struct dm_target field zone_append_not_supported, or because the device
table contains a non-zoned device, has its mapped device marked with the
new flag DMF_ZONE_APPEND_EMULATED. The helper function
dm_emulate_zone_append() is introduced to test a mapped device for this
new flag.
Atomicity of the zones write pointer tracking and updates is done using
a zone write locking mechanism based on a bitmap. This is similar to
the block layer method but based on BIOs rather than struct request.
A zone write lock is taken in dm_zone_map_bio() for any clone BIO with
an operation type that changes the BIO target zone write pointer
position. The zone write lock is released if the clone BIO is failed
before submission or when dm_zone_endio() is called when the clone BIO
completes.
The zone write lock bitmap of the mapped device, together with a bitmap
indicating zone types (conv_zones_bitmap) and the write pointer offset
array (zwp_offset) are allocated and initialized with a full device zone
report in dm_set_zones_restrictions() using the function
dm_revalidate_zones().
For failed operations that may have modified a zone write pointer, the
zone write pointer offset is marked as invalid in dm_zone_endio().
Zones with an invalid write pointer offset are checked and the write
pointer updated using an internal report zone operation when the
faulty zone is accessed again by the user.
All functions added for this emulation have a minimal overhead for
zoned targets natively supporting zone append operations. Regular
device targets are also not affected. The added code also does not
impact builds with CONFIG_BLK_DEV_ZONED disabled by stubbing out all
dm zone related functions.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Move the definitions of struct dm_target_io, struct dm_io and the bits
of the flags field of struct mapped_device from dm.c to dm-core.h to
make them usable from dm-zone.c. For the same reason, declare
dec_pending() in dm-core.h after renaming it to dm_io_dec_pending().
And for symmetry of the function names, introduce the inline helper
dm_io_inc_pending() instead of directly using atomic_inc() calls.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
A target map method requesting the requeue of a bio with
DM_MAPIO_REQUEUE or completing it with DM_ENDIO_REQUEUE can cause
unaligned write errors if the bio is a write operation targeting a
sequential zone. If a zoned target request such a requeue, warn about
it and kill the IO.
The function dm_is_zone_write() is introduced to detect write operations
to zoned targets.
This change does not affect the target drivers supporting zoned devices
and exposing a zoned device, namely dm-crypt, dm-linear and dm-flakey as
none of these targets ever request a requeue.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Move core and table code used for zoned targets and conditionally
defined with #ifdef CONFIG_BLK_DEV_ZONED to the new file dm-zone.c.
This file is conditionally compiled depending on CONFIG_BLK_DEV_ZONED.
The small helper dm_set_zones_restrictions() is introduced to
initialize a mapped device request queue zone attributes in
dm_table_set_restrictions().
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fix dm_accept_partial_bio() to actually check that zone management
commands are not passed as explained in the function documentation
comment. Also, since a zone append operation cannot be split, add
REQ_OP_ZONE_APPEND as a forbidden command.
White lines are added around the group of BUG_ON() calls to make the
code more legible.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Convert the dm driver to use the blk_alloc_disk and blk_cleanup_disk
helpers to simplify gendisk and request_queue allocation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
These are only used by DM core, DM target modules should only use
dm_{get,put}_device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Remove useless "while" loop. If the condition ci.sector_count && !error is
true, we go to a branch that ends with "break". If this condition is
false, the "while" loop will not be executed again. So, the loop can't be
executed more than once.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When a DM device is first created it doesn't yet have an established
capacity, therefore the use of set_capacity_and_notify() should be
conditional given the potential for needless pr_info "detected
capacity change" noise even if capacity is 0.
One could argue that the pr_info() in set_capacity_and_notify() is
misplaced, but that position is not held uniformly.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: f64d9b2eac ("dm: use set_capacity_and_notify")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The system would deadlock when swapping to a dm-crypt device. The reason
is that for each incoming write bio, dm-crypt allocates memory that holds
encrypted data. These excessive allocations exhaust all the memory and the
result is either deadlock or OOM trigger.
This patch limits the number of in-flight swap bios, so that the memory
consumed by dm-crypt is limited. The limit is enforced if the target set
the "limit_swap_bios" variable and if the bio has REQ_SWAP set.
Non-swap bios are not affected becuase taking the semaphore would cause
performance degradation.
This is similar to request-based drivers - they will also block when the
number of requests is over the limit.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Update the device-mapper core to support exposing the inline crypto
support of the underlying device(s) through the device-mapper device.
This works by creating a "passthrough keyslot manager" for the dm
device, which declares support for encryption settings which all
underlying devices support. When a supported setting is used, the bio
cloning code handles cloning the crypto context to the bios for all the
underlying devices. When an unsupported setting is used, the blk-crypto
fallback is used as usual.
Crypto support on each underlying device is ignored unless the
corresponding dm target opts into exposing it. This is needed because
for inline crypto to semantically operate on the original bio, the data
must not be transformed by the dm target. Thus, targets like dm-linear
can expose crypto support of the underlying device, but targets like
dm-crypt can't. (dm-crypt could use inline crypto itself, though.)
A DM device's table can only be changed if the "new" inline encryption
capabilities are a (*not* necessarily strict) superset of the "old" inline
encryption capabilities. Attempts to make changes to the table that result
in some inline encryption capability becoming no longer supported will be
rejected.
For the sake of clarity, key eviction from underlying devices will be
handled in a future patch.
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fix dm_table_supports_dax() and invert logic of both
iterate_devices_callout_fn so that all devices' DAX capabilities are
properly checked.
Fixes: 545ed20e6d ("dm: add infrastructure for DAX support")
Cc: stable@vger.kernel.org
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add two helper macros calculating the offset of bio in struct dm_io and
struct dm_target_io respectively.
Besides, simplify the front padding calculation in
dm_alloc_md_mempools().
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device. From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There wasn't ever a real need to log an error in the kernel log for
ioctls issued with insufficient permissions. Simply return an error
and if an admin/user is sufficiently motivated they can enable DM's
dynamic debugging to see an explanation for why the ioctls were
disallowed.
Reported-by: Nir Soffer <nsoffer@redhat.com>
Fixes: e980f62353 ("dm: don't allow ioctls to targets that don't map to whole devices")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
- Fix DM verity to skip verity work if IO completes with error while
system is shutting down.
- Add new DM multipath "IO affinity" path selector that maps IO
destined to a given path to a specific CPU based on user provided
mapping.
- Rename DM multipath path selector source files to have "dm-ps"
prefix.
- Add REQ_NOWAIT support to some other simple DM targets that don't
block in more elaborate ways waiting for IO.
- Export DM crypt's kcryptd workqueue via sysfs (WQ_SYSFS).
- Fix error return code in DM's target_message() if empty message is
received.
- A handful of other small cleanups.
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Merge tag 'for-5.11/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- Add DM verity support for signature verification with 2nd keyring
- Fix DM verity to skip verity work if IO completes with error while
system is shutting down
- Add new DM multipath "IO affinity" path selector that maps IO
destined to a given path to a specific CPU based on user provided
mapping
- Rename DM multipath path selector source files to have "dm-ps" prefix
- Add REQ_NOWAIT support to some other simple DM targets that don't
block in more elaborate ways waiting for IO
- Export DM crypt's kcryptd workqueue via sysfs (WQ_SYSFS)
- Fix error return code in DM's target_message() if empty message is
received
- A handful of other small cleanups
* tag 'for-5.11/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm cache: simplify the return expression of load_mapping()
dm ebs: avoid double unlikely() notation when using IS_ERR()
dm verity: skip verity work if I/O error when system is shutting down
dm crypt: export sysfs of kcryptd workqueue
dm ioctl: fix error return code in target_message
dm crypt: Constify static crypt_iv_operations
dm: add support for REQ_NOWAIT to various targets
dm: rename multipath path selector source files to have "dm-ps" prefix
dm mpath: add IO affinity path selector
dm verity: Add support for signature verification with 2nd keyring
dm: remove unnecessary current->bio_list check when submitting split bio
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Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
"Another series of killing more code than what is being added, again
thanks to Christoph's relentless cleanups and tech debt tackling.
This contains:
- blk-iocost improvements (Baolin Wang)
- part0 iostat fix (Jeffle Xu)
- Disable iopoll for split bios (Jeffle Xu)
- block tracepoint cleanups (Christoph Hellwig)
- Merging of struct block_device and hd_struct (Christoph Hellwig)
- Rework/cleanup of how block device sizes are updated (Christoph
Hellwig)
- Simplification of gendisk lookup and removal of block device
aliasing (Christoph Hellwig)
- Block device ioctl cleanups (Christoph Hellwig)
- Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig)
- Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig)
- sbitmap improvements (Pavel Begunkov)
- Hybrid polling fix (Pavel Begunkov)
- bvec iteration improvements (Pavel Begunkov)
- Zone revalidation fixes (Damien Le Moal)
- blk-throttle limit fix (Yu Kuai)
- Various little fixes"
* tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits)
blk-mq: fix msec comment from micro to milli seconds
blk-mq: update arg in comment of blk_mq_map_queue
blk-mq: add helper allocating tagset->tags
Revert "block: Fix a lockdep complaint triggered by request queue flushing"
nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class
blk-mq: add new API of blk_mq_hctx_set_fq_lock_class
block: disable iopoll for split bio
block: Improve blk_revalidate_disk_zones() checks
sbitmap: simplify wrap check
sbitmap: replace CAS with atomic and
sbitmap: remove swap_lock
sbitmap: optimise sbitmap_deferred_clear()
blk-mq: skip hybrid polling if iopoll doesn't spin
blk-iocost: Factor out the base vrate change into a separate function
blk-iocost: Factor out the active iocgs' state check into a separate function
blk-iocost: Move the usage ratio calculation to the correct place
blk-iocost: Remove unnecessary advance declaration
blk-iocost: Fix some typos in comments
blktrace: fix up a kerneldoc comment
block: remove the request_queue to argument request based tracepoints
...
The depth-first splitting is introduced in commit 18a25da843 ("dm:
ensure bio submission follows a depth-first tree walk"), which is used
to fix the potential deadlock in case of the misordering handling of
bios caused by bio_list. There're two paths submitting split bios,
dm_wq_work() from worker thread and submit_bio() from application. Back
upon that time, dm_wq_work() thread calls __split_and_process_bio()
directly and thus will not trigger this issue since bio_list doesn't
exist here. So this issue will only be triggered from application
calling submit_bio(), and the fix has to check if current->bio_list is
non-NULL to distinguish this case.
However since commit 0c2915b8c6 ("dm: fix missing imposition of
queue_limits from dm_wq_work() thread"), dm_wq_work() thread calls
submit_bio_noacct() and thus also uses bio_list. Since then all entries
into __split_and_process_bio() are under protection of bio_list, and
thus the checking of current->bio_list when determinning if the
depth-first principle should be used, seems kind of nonsense. After all
the checking always succeeds now.
Fixes: 0c2915b8c6 ("dm: fix missing imposition of queue_limits from dm_wq_work() thread")
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fixes sparse warnings:
drivers/md/dm.c:508:12: warning: context imbalance in 'dm_prepare_ioctl' - wrong count at exit
drivers/md/dm.c:543:13: warning: context imbalance in 'dm_unprepare_ioctl' - wrong count at exit
Fixes: 971888c469 ("dm: hold DM table for duration of ioctl rather than use blkdev_get")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 882ec4e609 ("dm table: stack 'chunk_sectors' limit to account
for target-specific splitting") caused a couple regressions:
1) Using lcm_not_zero() when stacking chunk_sectors was a bug because
chunk_sectors must reflect the most limited of all devices in the
IO stack.
2) DM targets that set max_io_len but that do _not_ provide an
.iterate_devices method no longer had there IO split properly.
And commit 5091cdec56 ("dm: change max_io_len() to use
blk_max_size_offset()") also caused a regression where DM no longer
supported varied (per target) IO splitting. The implication being the
potential for severely reduced performance for IO stacks that use a DM
target like dm-cache to hide performance limitations of a slower
device (e.g. one that requires 4K IO splitting).
Coming full circle: Fix all these issues by discontinuing stacking
chunk_sectors up using ti->max_io_len in dm_calculate_queue_limits(),
add optional chunk_sectors override argument to blk_max_size_offset()
and update DM's max_io_len() to pass ti->max_io_len to its
blk_max_size_offset() call.
Passing in an optional chunk_sectors override to blk_max_size_offset()
allows for code reuse of block's centralized calculation for max IO
size based on provided offset and split boundary.
Fixes: 882ec4e609 ("dm table: stack 'chunk_sectors' limit to account for target-specific splitting")
Fixes: 5091cdec56 ("dm: change max_io_len() to use blk_max_size_offset()")
Cc: stable@vger.kernel.org
Reported-by: John Dorminy <jdorminy@redhat.com>
Reported-by: Bruce Johnston <bjohnsto@redhat.com>
Reported-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: John Dorminy <jdorminy@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
The request_queue can trivially be derived from the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The request_queue can trivially be derived from the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We can just dereference the point in struct gendisk instead. Also
remove the now unused export.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use struct block_device to lookup partitions on a disk. This removes
all usage of struct hd_struct from the I/O path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: Chao Yu <yuchao0@huawei.com> [f2fs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allocate hd_struct together with struct block_device to pre-load
the lifetime rule changes in preparation of merging the two structures.
Note that part0 was previously embedded into struct gendisk, but is
a separate allocation now, and already points to the block_device instead
of the hd_struct. The lifetime of struct gendisk is still controlled by
the struct device embedded in the part0 hd_struct.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Get rid of the long-lasting struct block_device reference in
struct mapped_device. The only remaining user is the freeze code,
where we can trivially look up the block device at freeze time
and release the reference at thaw time.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We don't really need the struct block_device to initialize a bio. So
switch from using bio_set_dev to manually setting up bi_disk (bi_partno
will always be zero and has been cleared by bio_init already).
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
