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path: root/drivers/md/dm-linear.c
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2020-09-25dm: add support for REQ_NOWAIT and enable it for linear targetKonstantin Khlebnikov1-2/+3
Add DM target feature flag DM_TARGET_NOWAIT which advertises that target works with REQ_NOWAIT bios. Add dm_table_supports_nowait() and update dm_table_set_restrictions() to set/clear QUEUE_FLAG_NOWAIT accordingly. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-03dm,dax: Add dax zero_page_range operationVivek Goyal1-0/+18
This patch adds support for dax zero_page_range operation to dm targets. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20200228163456.1587-5-vgoyal@redhat.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-11-13block: rework zone reportingChristoph Hellwig1-13/+7
Avoid the need to allocate a potentially large array of struct blk_zone in the block layer by switching the ->report_zones method interface to a callback model. Now the caller simply supplies a callback that is executed on each reported zone, and private data for it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-07dm: add zone open, close and finish supportAjay Joshi1-1/+1
Implement REQ_OP_ZONE_OPEN, REQ_OP_ZONE_CLOSE and REQ_OP_ZONE_FINISH support to allow explicit control of zone states. Contains contributions from Matias Bjorling, Hans Holmberg and Damien Le Moal. Acked-by: Mike Snitzer <snitzer@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ajay Joshi <ajay.joshi@wdc.com> Signed-off-by: Matias Bjorling <matias.bjorling@wdc.com> Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-07-12block: Kill gfp_t argument of blkdev_report_zones()Damien Le Moal1-3/+2
Only GFP_KERNEL and GFP_NOIO are used with blkdev_report_zones(). In preparation of using vmalloc() for large report buffer and zone array allocations used by this function, remove its "gfp_t gfp_mask" argument and rely on the caller context to use memalloc_noio_save/restore() where necessary (block layer zone revalidation and dm-zoned I/O error path). Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18dm: Check for device sector overflow if CONFIG_LBDAF is not setMilan Broz1-1/+1
Reference to a device in device-mapper table contains offset in sectors. If the sector_t is 32bit integer (CONFIG_LBDAF is not set), then several device-mapper targets can overflow this offset and validity check is then performed on a wrong offset and a wrong table is activated. See for example (on 32bit without CONFIG_LBDAF) this overflow: # dmsetup create test --table "0 2048 linear /dev/sdg 4294967297" # dmsetup table test 0 2048 linear 8:96 1 This patch adds explicit check for overflow if the offset is sector_t type. Signed-off-by: Milan Broz <gmazyland@gmail.com> Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-10-25block: add a report_zones methodChristoph Hellwig1-14/+21
Dispatching a report zones command through the request queue is a major pain due to the command reply payload rewriting necessary. Given that blkdev_report_zones() is executing everything synchronously, implement report zones as a block device file operation instead, allowing major simplification of the code in many places. sd, null-blk, dm-linear and dm-flakey being the only block device drivers supporting exposing zoned block devices, these drivers are modified to provide the device side implementation of the report_zones() block device file operation. For device mappers, a new report_zones() target type operation is defined so that the upper block layer calls blkdev_report_zones() can be propagated down to the underlying devices of the dm targets. Implementation for this new operation is added to the dm-linear and dm-flakey targets. Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> [Damien] * Changed method block_device argument to gendisk * Various bug fixes and improvements * Added support for null_blk, dm-linear and dm-flakey. Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-10-11dm linear: fix linear_end_io conditional definitionDamien Le Moal1-2/+2
The dm-linear target is independent of the dm-zoned target. For code requiring support for zoned block devices, use CONFIG_BLK_DEV_ZONED instead of CONFIG_DM_ZONED. While at it, similarly to dm linear, also enable the DM_TARGET_ZONED_HM feature in dm-flakey only if CONFIG_BLK_DEV_ZONED is defined. Fixes: beb9caac211c1 ("dm linear: eliminate linear_end_io call if CONFIG_DM_ZONED disabled") Fixes: 0be12c1c7fce7 ("dm linear: add support for zoned block devices") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-10-10dm linear: eliminate linear_end_io call if CONFIG_DM_ZONED disabledMike Snitzer1-1/+7
It is best to avoid any extra overhead associated with bio completion. DM core will indirectly call a DM target's .end_io if it is defined. In the case of DM linear, there is no need to do so (for every bio that completes) if CONFIG_DM_ZONED is not enabled. Avoiding an extra indirect call for every bio completion is very important for ensuring DM linear doesn't incur more overhead that further widens the performance gap between dm-linear and raw block devices. Fixes: 0be12c1c7fce7 ("dm linear: add support for zoned block devices") Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-05-23dax: Introduce a ->copy_to_iter dax operationDan Williams1-0/+16
Similar to the ->copy_from_iter() operation, a platform may want to deploy an architecture or device specific routine for handling reads from a dax_device like /dev/pmemX. On x86 this routine will point to a machine check safe version of copy_to_iter(). For now, add the plumbing to device-mapper and the dax core. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-04-10Merge tag 'libnvdimm-for-4.17' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: "This cycle was was not something I ever want to repeat as there were several late changes that have only now just settled. Half of the branch up to commit d2c997c0f145 ("fs, dax: use page->mapping to warn...") have been in -next for several releases. The of_pmem driver and the address range scrub rework were late arrivals, and the dax work was scaled back at the last moment. The of_pmem driver missed a previous merge window due to an oversight. A sense of obligation to rectify that miss is why it is included for 4.17. It has acks from PowerPC folks. Stephen reported a build failure that only occurs when merging it with your latest tree, for now I have fixed that up by disabling modular builds of of_pmem. A test merge with your tree has received a build success report from the 0day robot over 156 configs. An initial version of the ARS rework was submitted before the merge window. It is self contained to libnvdimm, a net code reduction, and passing all unit tests. The filesystem-dax changes are based on the wait_var_event() functionality from tip/sched/core. However, late review feedback showed that those changes regressed truncate performance to a large degree. The branch was rewound to drop the truncate behavior change and now only includes preparation patches and cleanups (with full acks and reviews). The finalization of this dax-dma-vs-trnucate work will need to wait for 4.18. Summary: - A rework of the filesytem-dax implementation provides for detection of unmap operations (truncate / hole punch) colliding with in-progress device-DMA. A fix for these collisions remains a work-in-progress pending resolution of truncate latency and starvation regressions. - The of_pmem driver expands the users of libnvdimm outside of x86 and ACPI to describe an implementation of persistent memory on PowerPC with Open Firmware / Device tree. - Address Range Scrub (ARS) handling is completely rewritten to account for the fact that ARS may run for 100s of seconds and there is no platform defined way to cancel it. ARS will now no longer block namespace initialization. - The NVDIMM Namespace Label implementation is updated to handle label areas as small as 1K, down from 128K. - Miscellaneous cleanups and updates to unit test infrastructure" * tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (39 commits) libnvdimm, of_pmem: workaround OF_NUMA=n build error nfit, address-range-scrub: add module option to skip initial ars nfit, address-range-scrub: rework and simplify ARS state machine nfit, address-range-scrub: determine one platform max_ars value powerpc/powernv: Create platform devs for nvdimm buses doc/devicetree: Persistent memory region bindings libnvdimm: Add device-tree based driver libnvdimm: Add of_node to region and bus descriptors libnvdimm, region: quiet region probe libnvdimm, namespace: use a safe lookup for dimm device name libnvdimm, dimm: fix dpa reservation vs uninitialized label area libnvdimm, testing: update the default smart ctrl_temperature libnvdimm, testing: Add emulation for smart injection commands nfit, address-range-scrub: introduce nfit_spa->ars_state libnvdimm: add an api to cast a 'struct nd_region' to its 'struct device' nfit, address-range-scrub: fix scrub in-progress reporting dax, dm: allow device-mapper to operate without dax support dax: introduce CONFIG_DAX_DRIVER fs, dax: use page->mapping to warn if truncate collides with a busy page ext2, dax: introduce ext2_dax_aops ...
2018-04-04dm: remove fmode_t argument from .prepare_ioctl hookMike Snitzer1-2/+1
Use the fmode_t that is passed to dm_blk_ioctl() rather than inconsistently (varies across targets) drop it on the floor by overriding it with the fmode_t stored in 'struct dm_dev'. All the persistent reservation functions weren't using the fmode_t they got back from .prepare_ioctl so remove them. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03dm: add support for secure erase forwardingDenis Semakin1-0/+1
Set QUEUE_FLAG_SECERASE in DM device's queue_flags if a DM table's data devices support secure erase. Also, add support for secure erase to both the linear and striped targets. Signed-off-by: Denis Semakin <d.semakin@omprussia.ru> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03dax, dm: allow device-mapper to operate without dax supportDan Williams1-0/+6
Change device-mapper's DAX dependency to require the presence of at least one DAX_DRIVER. This allows device-mapper to be built without bringing the DAX core along which is especially wasteful when there are no DAX drivers, like BLK_DEV_PMEM, configured. Cc: Alasdair Kergon <agk@redhat.com> Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com> Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-14Merge tag 'for-4.14/dm-changes' of ↵Linus Torvalds1-15/+0
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm 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
2017-09-11dax: remove the pmem_dax_ops->flush abstractionMikulas Patocka1-15/+0
Commit abebfbe2f731 ("dm: add ->flush() dax operation support") is buggy. A DM device may be composed of multiple underlying devices and all of them need to be flushed. That commit just routes the flush request to the first device and ignores the other devices. It could be fixed by adding more complex logic to the device mapper. But there is only one implementation of the method pmem_dax_ops->flush - that is pmem_dax_flush() - and it calls arch_wb_cache_pmem(). Consequently, we don't need the pmem_dax_ops->flush abstraction at all, we can call arch_wb_cache_pmem() directly from dax_flush() because dax_dev->ops->flush can't ever reach anything different from arch_wb_cache_pmem(). It should be also pointed out that for some uses of persistent memory it is needed to flush only a very small amount of data (such as 1 cacheline), and it would be overkill if we go through that device mapper machinery for a single flushed cache line. Fix this by removing the pmem_dax_ops->flush abstraction and call arch_wb_cache_pmem() directly from dax_flush(). Also, remove the device mapper code that forwards the flushes. Fixes: abebfbe2f731 ("dm: add ->flush() dax operation support") Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-08-23block: replace bi_bdev with a gendisk pointer and partitions indexChristoph Hellwig1-1/+1
This way we don't need a block_device structure to submit I/O. The block_device has different life time rules from the gendisk and request_queue and is usually only available when the block device node is open. Other callers need to explicitly create one (e.g. the lightnvm passthrough code, or the new nvme multipathing code). For the actual I/O path all that we need is the gendisk, which exists once per block device. But given that the block layer also does partition remapping we additionally need a partition index, which is used for said remapping in generic_make_request. Note that all the block drivers generally want request_queue or sometimes the gendisk, so this removes a layer of indirection all over the stack. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-07Merge tag 'libnvdimm-for-4.13' of ↵Linus Torvalds1-0/+30
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: "libnvdimm updates for the latest ACPI and UEFI specifications. This pull request also includes new 'struct dax_operations' enabling to undo the abuse of copy_user_nocache() for copy operations to pmem. The dax work originally missed 4.12 to address concerns raised by Al. Summary: - Introduce the _flushcache() family of memory copy helpers and use them for persistent memory write operations on x86. The _flushcache() semantic indicates that the cache is either bypassed for the copy operation (movnt) or any lines dirtied by the copy operation are written back (clwb, clflushopt, or clflush). - Extend dax_operations with ->copy_from_iter() and ->flush() operations. These operations and other infrastructure updates allow all persistent memory specific dax functionality to be pushed into libnvdimm and the pmem driver directly. It also allows dax-specific sysfs attributes to be linked to a host device, for example: /sys/block/pmem0/dax/write_cache - Add support for the new NVDIMM platform/firmware mechanisms introduced in ACPI 6.2 and UEFI 2.7. This support includes the v1.2 namespace label format, extensions to the address-range-scrub command set, new error injection commands, and a new BTT (block-translation-table) layout. These updates support inter-OS and pre-OS compatibility. - Fix a longstanding memory corruption bug in nfit_test. - Make the pmem and nvdimm-region 'badblocks' sysfs files poll(2) capable. - Miscellaneous fixes and small updates across libnvdimm and the nfit driver. Acknowledgements that came after the branch was pushed: commit 6aa734a2f38e ("libnvdimm, region, pmem: fix 'badblocks' sysfs_get_dirent() reference lifetime") was reviewed by Toshi Kani <toshi.kani@hpe.com>" * tag 'libnvdimm-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (42 commits) libnvdimm, namespace: record 'lbasize' for pmem namespaces acpi/nfit: Issue Start ARS to retrieve existing records libnvdimm: New ACPI 6.2 DSM functions acpi, nfit: Show bus_dsm_mask in sysfs libnvdimm, acpi, nfit: Add bus level dsm mask for pass thru. acpi, nfit: Enable DSM pass thru for root functions. libnvdimm: passthru functions clear to send libnvdimm, btt: convert some info messages to warn/err libnvdimm, region, pmem: fix 'badblocks' sysfs_get_dirent() reference lifetime libnvdimm: fix the clear-error check in nsio_rw_bytes libnvdimm, btt: fix btt_rw_page not returning errors acpi, nfit: quiet invalid block-aperture-region warnings libnvdimm, btt: BTT updates for UEFI 2.7 format acpi, nfit: constify *_attribute_group libnvdimm, pmem: disable dax flushing when pmem is fronting a volatile region libnvdimm, pmem, dax: export a cache control attribute dax: convert to bitmask for flags dax: remove default copy_from_iter fallback libnvdimm, nfit: enable support for volatile ranges libnvdimm, pmem: fix persistence warning ...
2017-06-19dm linear: add support for zoned block devicesDamien Le Moal1-3/+15
Add support for zoned block devices by allowing host-managed zoned block device mapped targets, the remapping of REQ_OP_ZONE_RESET and the post processing (reply remapping) of REQ_OP_ZONE_REPORT. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-06-16dm: add ->flush() dax operation supportDan Williams1-0/+15
Allow device-mapper to route flush operations to the per-target implementation. In order for the device stacking to work we need a dax_dev and a pgoff relative to that device. This gives each layer of the stack the information it needs to look up the operation pointer for the next level. This conceptually allows for an array of mixed device drivers with varying flush implementations. Reviewed-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-09dm: add ->copy_from_iter() dax operation supportDan Williams1-0/+15
Allow device-mapper to route copy_from_iter operations to the per-target implementation. In order for the device stacking to work we need a dax_dev and a pgoff relative to that device. This gives each layer of the stack the information it needs to look up the operation pointer for the next level. This conceptually allows for an array of mixed device drivers with varying copy_from_iter implementations. Reviewed-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-06Merge tag 'libnvdimm-for-4.12' of ↵Linus Torvalds1-14/+13
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: "The bulk of this has been in multiple -next releases. There were a few late breaking fixes and small features that got added in the last couple days, but the whole set has received a build success notification from the kbuild robot. Change summary: - Region media error reporting: A libnvdimm region device is the parent to one or more namespaces. To date, media errors have been reported via the "badblocks" attribute attached to pmem block devices for namespaces in "raw" or "memory" mode. Given that namespaces can be in "device-dax" or "btt-sector" mode this new interface reports media errors generically, i.e. independent of namespace modes or state. This subsequently allows userspace tooling to craft "ACPI 6.1 Section 9.20.7.6 Function Index 4 - Clear Uncorrectable Error" requests and submit them via the ioctl path for NVDIMM root bus devices. - Introduce 'struct dax_device' and 'struct dax_operations': Prompted by a request from Linus and feedback from Christoph this allows for dax capable drivers to publish their own custom dax operations. This fixes the broken assumption that all dax operations are related to a persistent memory device, and makes it easier for other architectures and platforms to add customized persistent memory support. - 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is available for storage appliance applications to manually trigger memory controllers to drain write-pending buffers that would otherwise be flushed automatically by the platform ADR (asynchronous-DRAM-refresh) mechanism at a power loss event. Support for "locked" DIMMs is included to prevent namespaces from surfacing when the namespace label data area is locked. Finally, fixes for various reported deadlocks and crashes, also tagged for -stable. - ACPI / nfit driver updates: General updates of the nfit driver to add DSM command overrides, ACPI 6.1 health state flags support, DSM payload debug available by default, and various fixes. Acknowledgements that came after the branch was pushed: - commmit 565851c972b5 "device-dax: fix sysfs attribute deadlock": Tested-by: Yi Zhang <yizhan@redhat.com> - commit 23f498448362 "libnvdimm: rework region badblocks clearing" Tested-by: Toshi Kani <toshi.kani@hpe.com>" * tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (52 commits) libnvdimm, pfn: fix 'npfns' vs section alignment libnvdimm: handle locked label storage areas libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED brd: fix uninitialized use of brd->dax_dev block, dax: use correct format string in bdev_dax_supported device-dax: fix sysfs attribute deadlock libnvdimm: restore "libnvdimm: band aid btt vs clear poison locking" libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering libnvdimm: rework region badblocks clearing acpi, nfit: kill ACPI_NFIT_DEBUG libnvdimm: fix clear length of nvdimm_forget_poison() libnvdimm, pmem: fix a NULL pointer BUG in nd_pmem_notify libnvdimm, region: sysfs trigger for nvdimm_flush() libnvdimm: fix phys_addr for nvdimm_clear_poison x86, dax, pmem: remove indirection around memcpy_from_pmem() block: remove block_device_operations ->direct_access() block, dax: convert bdev_dax_supported() to dax_direct_access() filesystem-dax: convert to dax_direct_access() Revert "block: use DAX for partition table reads" ext2, ext4, xfs: retrieve dax_device for iomap operations ...
2017-05-03Merge tag 'for-4.12/dm-changes' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - A major update for DM cache that reduces the latency for deciding whether blocks should migrate to/from the cache. The bio-prison-v2 interface supports this improvement by enabling direct dispatch of work to workqueues rather than having to delay the actual work dispatch to the DM cache core. So the dm-cache policies are much more nimble by being able to drive IO as they see fit. One immediate benefit from the improved latency is a cache that should be much more adaptive to changing workloads. - Add a new DM integrity target that emulates a block device that has additional per-sector tags that can be used for storing integrity information. - Add a new authenticated encryption feature to the DM crypt target that builds on the capabilities provided by the DM integrity target. - Add MD interface for switching the raid4/5/6 journal mode and update the DM raid target to use it to enable aid4/5/6 journal write-back support. - Switch the DM verity target over to using the asynchronous hash crypto API (this helps work better with architectures that have access to off-CPU algorithm providers, which should reduce CPU utilization). - Various request-based DM and DM multipath fixes and improvements from Bart and Christoph. - A DM thinp target fix for a bio structure leak that occurs for each discard IFF discard passdown is enabled. - A fix for a possible deadlock in DM bufio and a fix to re-check the new buffer allocation watermark in the face of competing admin changes to the 'max_cache_size_bytes' tunable. - A couple DM core cleanups. * tag 'for-4.12/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (50 commits) dm bufio: check new buffer allocation watermark every 30 seconds dm bufio: avoid a possible ABBA deadlock dm mpath: make it easier to detect unintended I/O request flushes dm mpath: cleanup QUEUE_IF_NO_PATH bit manipulation by introducing assign_bit() dm mpath: micro-optimize the hot path relative to MPATHF_QUEUE_IF_NO_PATH dm: introduce enum dm_queue_mode to cleanup related code dm mpath: verify __pg_init_all_paths locking assumptions at runtime dm: verify suspend_locking assumptions at runtime dm block manager: remove an unused argument from dm_block_manager_create() dm rq: check blk_mq_register_dev() return value in dm_mq_init_request_queue() dm mpath: delay requeuing while path initialization is in progress dm mpath: avoid that path removal can trigger an infinite loop dm mpath: split and rename activate_path() to prepare for its expanded use dm ioctl: prevent stack leak in dm ioctl call dm integrity: use previously calculated log2 of sectors_per_block dm integrity: use hex2bin instead of open-coded variant dm crypt: replace custom implementation of hex2bin() dm crypt: remove obsolete references to per-CPU state dm verity: switch to using asynchronous hash crypto API dm crypt: use WQ_HIGHPRI for the IO and crypt workqueues ...
2017-04-25dm: teach dm-targets to use a dax_device + dax_operationsDan Williams1-14/+13
Arrange for dm to lookup the dax services available from member devices. Update the dax-capable targets, linear and stripe, to route dax operations to the underlying device. Changes the target-internal ->direct_access() method to more closely align with the dax_operations ->direct_access() calling convention. Cc: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-24dm: mark targets that pass integrity dataMikulas Patocka1-0/+1
A dm-crypt on dm-integrity device incorrectly advertises an integrity profile on the DM crypt device. It can be seen in the files "/sys/block/dm-*/integrity/*" that both dm-integrity and dm-crypt target advertise the integrity profile. That is incorrect, only the dm-integrity target should advertise the integrity profile. A general problem in DM is that if we have a DM device that depends on another device with an integrity profile, the upper device will always advertise the integrity profile, even when the target driver doesn't support handling integrity data. Most targets don't support integrity data, so we provide a whitelist of targets that support it (linear, delay and striped). The targets that support passing integrity data to the lower device are marked with the flag DM_TARGET_PASSES_INTEGRITY. The DM core will now advertise integrity data on a DM device only if all the targets support the integrity data. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-04-08dm: support REQ_OP_WRITE_ZEROESChristoph Hellwig1-0/+1
Copy & paste from the REQ_OP_WRITE_SAME code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-07-29Merge tag 'libnvdimm-for-4.8' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: - Replace pcommit with ADR / directed-flushing. The pcommit instruction, which has not shipped on any product, is deprecated. Instead, the requirement is that platforms implement either ADR, or provide one or more flush addresses per nvdimm. ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers to the memory controller on a power-fail event. Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware Interface Table (NFIT) sub-structure: "Flush Hint Address Structure". A flush hint is an mmio address that when written and fenced assures that all previous posted writes targeting a given dimm have been flushed to media. - On-demand ARS (address range scrub). Linux uses the results of the ACPI ARS commands to track bad blocks in pmem devices. When latent errors are detected we re-scrub the media to refresh the bad block list, userspace can also request a re-scrub at any time. - Support for the Microsoft DSM (device specific method) command format. - Support for EDK2/OVMF virtual disk device memory ranges. - Various fixes and cleanups across the subsystem. * tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits) libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register" nfit: do an ARS scrub on hitting a latent media error nfit: move to nfit/ sub-directory nfit, libnvdimm: allow an ARS scrub to be triggered on demand libnvdimm: register nvdimm_bus devices with an nd_bus driver pmem: clarify a debug print in pmem_clear_poison x86/insn: remove pcommit Revert "KVM: x86: add pcommit support" nfit, tools/testing/nvdimm/: unify shutdown paths libnvdimm: move ->module to struct nvdimm_bus_descriptor nfit: cleanup acpi_nfit_init calling convention nfit: fix _FIT evaluation memory leak + use after free tools/testing/nvdimm: add manufacturing_{date|location} dimm properties tools/testing/nvdimm: add virtual ramdisk range acpi, nfit: treat virtual ramdisk SPA as pmem region pmem: kill __pmem address space pmem: kill wmb_pmem() libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes fs/dax: remove wmb_pmem() libnvdimm, pmem: flush posted-write queues on shutdown ...
2016-07-21dm linear: add DAX supportToshi Kani1-1/+20
Change dm-linear to implement direct_access function, linear_direct_access(), which maps sector and calls direct_access function of its physical target device. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-11-01dm linear: remove redundant target name from error messagesTomohiro Kusumi1-3/+3
Commit 72d94861 back in 2006 should have consistently removed "dm-linear: " from all error messages. Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-11-01dm: refactor ioctl handlingChristoph Hellwig1-7/+7
This moves the call to blkdev_ioctl and the argument checking to DM core code, and only leaves a callout to find the block device to operate on in the targets. This simplifies the code and allows us to pass through ioctl-like command using other methods in the next patch. Also split out a helper around calling the prepare_ioctl method that will be reused for persistent reservation handling. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-09-03Merge tag 'dm-4.3-changes' of ↵Linus Torvalds1-2/+5
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper update from Mike Snitzer: - a couple small cleanups in dm-cache, dm-verity, persistent-data's dm-btree, and DM core. - a 4.1-stable fix for dm-cache that fixes the leaking of deferred bio prison cells - a 4.2-stable fix that adds feature reporting for the dm-stats features added in 4.2 - improve DM-snapshot to not invalidate the on-disk snapshot if snapshot device write overflow occurs; but a write overflow triggered through the origin device will still invalidate the snapshot. - optimize DM-thinp's async discard submission a bit now that late bio splitting has been included in block core. - switch DM-cache's SMQ policy lock from using a mutex to a spinlock; improves performance on very low latency devices (eg. NVMe SSD). - document DM RAID 4/5/6's discard support [ I did not pull the slab changes, which weren't appropriate for this tree, and weren't obviously the right thing to do anyway. At the very least they need some discussion and explanation before getting merged. Because not pulling the actual tagged commit but doing a partial pull instead, this merge commit thus also obviously is missing the git signature from the original tag ] * tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm cache: fix use after freeing migrations dm cache: small cleanups related to deferred prison cell cleanup dm cache: fix leaking of deferred bio prison cells dm raid: document RAID 4/5/6 discard support dm stats: report precise_timestamps and histogram in @stats_list output dm thin: optimize async discard submission dm snapshot: don't invalidate on-disk image on snapshot write overflow dm: remove unlikely() before IS_ERR() dm: do not override error code returned from dm_get_device() dm: test return value for DM_MAPIO_SUBMITTED dm verity: remove unused mempool dm cache: move wake_waker() from free_migrations() to where it is needed dm btree remove: remove unused function get_nr_entries() dm btree: remove unused "dm_block_t root" parameter in btree_split_sibling() dm cache policy smq: change the mutex to a spinlock
2015-08-13block: kill merge_bvec_fn() completelyKent Overstreet1-16/+0
As generic_make_request() is now able to handle arbitrarily sized bios, it's no longer necessary for each individual block driver to define its own ->merge_bvec_fn() callback. Remove every invocation completely. Cc: Jens Axboe <axboe@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: drbd-user@lists.linbit.com Cc: Jiri Kosina <jkosina@suse.cz> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@kernel.org> Cc: ceph-devel@vger.kernel.org Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Neil Brown <neilb@suse.de> Cc: linux-raid@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Acked-by: NeilBrown <neilb@suse.de> (for the 'md' bits) Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> [dpark: also remove ->merge_bvec_fn() in dm-thin as well as dm-era-target, and resolve merge conflicts] Signed-off-by: Dongsu Park <dpark@posteo.net> Signed-off-by: Ming Lin <ming.l@ssi.samsung.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-12dm: do not override error code returned from dm_get_device()Vivek Goyal1-2/+5
Some of the device mapper targets override the error code returned by dm_get_device() and return either -EINVAL or -ENXIO. There is nothing gained by this override. It is better to propagate the returned error code unchanged to caller. This work was motivated by hitting an issue where the underlying device was busy but -EINVAL was being returned. After this change we get -EBUSY instead and it is easier to figure out the problem. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-11-24block: Abstract out bvec iteratorKent Overstreet1-1/+2
Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-03-02dm: rename request variables to biosAlasdair G Kergon1-3/+3
Use 'bio' in the name of variables and functions that deal with bios rather than 'request' to avoid confusion with the normal block layer use of 'request'. No functional changes. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-02dm: fix truncated status stringsMikulas Patocka1-4/+3
Avoid returning a truncated table or status string instead of setting the DM_BUFFER_FULL_FLAG when the last target of a table fills the buffer. When processing a table or status request, the function retrieve_status calls ti->type->status. If ti->type->status returns non-zero, retrieve_status assumes that the buffer overflowed and sets DM_BUFFER_FULL_FLAG. However, targets don't return non-zero values from their status method on overflow. Most targets returns always zero. If a buffer overflow happens in a target that is not the last in the table, it gets noticed during the next iteration of the loop in retrieve_status; but if a buffer overflow happens in the last target, it goes unnoticed and erroneously truncated data is returned. In the current code, the targets behave in the following way: * dm-crypt returns -ENOMEM if there is not enough space to store the key, but it returns 0 on all other overflows. * dm-thin returns errors from the status method if a disk error happened. This is incorrect because retrieve_status doesn't check the error code, it assumes that all non-zero values mean buffer overflow. * all the other targets always return 0. This patch changes the ti->type->status function to return void (because most targets don't use the return code). Overflow is detected in retrieve_status: if the status method fills up the remaining space completely, it is assumed that buffer overflow happened. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-22dm: remove map_infoMikulas Patocka1-2/+1
This patch removes map_info from bio-based device mapper targets. map_info is still used for request-based targets. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-22dm linear: add WRITE SAME supportMike Snitzer1-1/+2
The linear target can already support WRITE SAME requests so signal this by setting num_write_same_requests to 1. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm thin: commit before gathering statusAlasdair G Kergon1-1/+1
Commit outstanding metadata before returning the status for a dm thin pool so that the numbers reported are as up-to-date as possible. The commit is not performed if the device is suspended or if the DM_NOFLUSH_FLAG is supplied by userspace and passed to the target through a new 'status_flags' parameter in the target's dm_status_fn. The userspace dmsetup tool will support the --noflush flag with the 'dmsetup status' and 'dmsetup wait' commands from version 1.02.76 onwards. Tested-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28dm: reject trailing characters in sccanf inputMikulas Patocka1-1/+2
Device mapper uses sscanf to convert arguments to numbers. The problem is that the way we use it ignores additional unmatched characters in the scanned string. For example, this `if (sscanf(string, "%d", &number) == 1)' will match a number, but also it will match number with some garbage appended, like "123abc". As a result, device mapper accepts garbage after some numbers. For example the command `dmsetup create vg1-new --table "0 16384 linear 254:1bla 34816bla"' will pass without an error. This patch fixes all sscanf uses in device mapper. It appends "%c" with a pointer to a dummy character variable to every sscanf statement. The construct `if (sscanf(string, "%d%c", &number, &dummy) == 1)' succeeds only if string is a null-terminated number (optionally preceded by some whitespace characters). If there is some character appended after the number, sscanf matches "%c", writes the character to the dummy variable and returns 2. We check the return value for 1 and consequently reject numbers with some garbage appended. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-01-15dm: do not forward ioctls from logical volumes to the underlying devicePaolo Bonzini1-1/+11
A logical volume can map to just part of underlying physical volume. In this case, it must be treated like a partition. Based on a patch from Alasdair G Kergon. Cc: Alasdair G Kergon <agk@redhat.com> Cc: dm-devel@redhat.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-12dm: use dm_target_offset macroAlasdair G Kergon1-1/+1
Use new dm_target_offset() macro to avoid most references to ti->begin in dm targets. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12dm: linear support discardMike Snitzer1-0/+1
Allow discards to be passed through to linear mappings if at least one underlying device supports it. Discards will be forwarded only to devices that support them. A target that supports discards should set num_discard_requests to indicate how many times each discard request must be submitted to it. Verify table's underlying devices support discards prior to setting the associated DM device as capable of discards (via QUEUE_FLAG_DISCARD). Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Joe Thornber <thornber@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-03-06dm table: remove unused dm_get_device range parametersNikanth Karthikesan1-2/+1
Remove unused parameters(start and len) of dm_get_device() and fix the callers. Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-07-23dm table: pass correct dev area size to device_area_is_validMike Snitzer1-1/+1
Incorrect device area lengths are being passed to device_area_is_valid(). The regression appeared in 2.6.31-rc1 through commit 754c5fc7ebb417b23601a6222a6005cc2e7f2913. With the dm-stripe target, the size of the target (ti->len) was used instead of the stripe_width (ti->len/#stripes). An example of a consequent incorrect error message is: device-mapper: table: 254:0: sdb too small for target Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-06-22dm target:s introduce iterate devices fnMike Snitzer1-1/+10
Add .iterate_devices to 'struct target_type' to allow a function to be called for all devices in a DM target. Implemented it for all targets except those in dm-snap.c (origin and snapshot). (The raid1 version number jumps to 1.12 because we originally reserved 1.1 to 1.11 for 'block_on_error' but ended up using 'handle_errors' instead.) Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: martin.petersen@oracle.com
2009-06-22dm: linear support flushMikulas Patocka1-1/+3
Flush support for the linear target. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09dm: remove limited barrier supportMikulas Patocka1-1/+0
Prepare for full barrier implementation: first remove the restricted support. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06dm: support barriers on simple devicesAndi Kleen1-0/+1
Implement barrier support for single device DM devices This patch implements barrier support in DM for the common case of dm linear just remapping a single underlying device. In this case we can safely pass the barrier through because there can be no reordering between devices. NB. Any DM device might cease to support barriers if it gets reconfigured so code must continue to allow for a possible -EOPNOTSUPP on every barrier bio submitted. - agk Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06dm: consolidate target deregistration error handlingMikulas Patocka1-4/+1
Change dm_unregister_target to return void and use BUG() for error reporting. dm_unregister_target can only fail because of programming bug in the target driver. It can't fail because of user's behavior or disk errors. This patch changes unregister_target to return void and use BUG if someone tries to unregister non-registered target or unregister target that is in use. This patch removes code duplication (testing of error codes in all dm targets) and reports bugs in just one place, in dm_unregister_target. In some target drivers, these return codes were ignored, which could lead to a situation where bugs could be missed. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>