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* Merge branch 'for-linus' of ↵Linus Torvalds2016-12-145-10/+10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: NTB: correct ntb_spad_count comment typo misc: ibmasm: fix typo in error message Remove references to dead make variable LINUX_INCLUDE Remove last traces of ikconfig.h treewide: Fix printk() message errors Documentation/device-mapper: s/getsize/getsz/
| * Documentation/device-mapper: s/getsize/getsz/Michael Witten2016-12-145-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to `man blockdev': --getsize Print device size (32-bit!) in sectors. Deprecated in favor of the --getsz option. ... --getsz Get size in 512-byte sectors. Hence, occurrences of `--getsize' should be replaced with `--getsz', which this commit has achieved as follows: $ cd "$repo" $ git grep -l -e --getsz Documentation/device-mapper/delay.txt Documentation/device-mapper/dm-crypt.txt Documentation/device-mapper/linear.txt Documentation/device-mapper/log-writes.txt Documentation/device-mapper/striped.txt Documentation/device-mapper/switch.txt $ cd Documentation/device-mapper $ sed -i s/getsize/getsz/g * Signed-off-by: Michael Witten <mfwitten@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | Documentation: dm raid: define data_offset status fieldHeinz Mauelshagen2016-12-081-0/+4
| | | | | | | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* | dm crypt: add ability to use keys from the kernel key retention serviceOndrej Kozina2016-12-081-1/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel key service is a generic way to store keys for the use of other subsystems. Currently there is no way to use kernel keys in dm-crypt. This patch aims to fix that. Instead of key userspace may pass a key description with preceding ':'. So message that constructs encryption mapping now looks like this: <cipher> [<key>|:<key_string>] <iv_offset> <dev_path> <start> [<#opt_params> <opt_params>] where <key_string> is in format: <key_size>:<key_type>:<key_description> Currently we only support two elementary key types: 'user' and 'logon'. Keys may be loaded in dm-crypt either via <key_string> or using classical method and pass the key in hex representation directly. dm-crypt device initialised with a key passed in hex representation may be replaced with key passed in key_string format and vice versa. (Based on original work by Andrey Ryabinin) Signed-off-by: Ondrej Kozina <okozina@redhat.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* | dm raid: fix typos in Documentation/device-mapper/dm-raid.txtMasanari Iida2016-11-211-4/+4
|/ | | | | Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm raid: fix activation of existing raid4/10 devicesHeinz Mauelshagen2016-10-171-0/+1
| | | | | | | | | | | | | | dm-raid 1.9.0 fails to activate existing RAID4/10 devices that have the old superblock format (which does not have takeover/reshaping support that was added via commit 33e53f06850f). Fix validation path for old superblocks by reverting to the old raid4 layout and basing checks on mddev->new_{level,layout,...} members in super_init_validation(). Cc: stable@vger.kernel.org # 4.8 Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* block: rename bio bi_rw to bi_opfJens Axboe2016-08-071-1/+1
| | | | | | | | | | | | | Since commit 63a4cc24867d, bio->bi_rw contains flags in the lower portion and the op code in the higher portions. This means that old code that relies on manually setting bi_rw is most likely going to be broken. Instead of letting that brokeness linger, rename the member, to force old and out-of-tree code to break at compile time instead of at runtime. No intended functional changes in this commit. Signed-off-by: Jens Axboe <axboe@fb.com>
* dm raid: update Documentation about reshaping/takeover/additonal RAID typesHeinz Mauelshagen2016-06-151-3/+55
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* block, drivers, fs: rename REQ_FLUSH to REQ_PREFLUSHMike Christie2016-06-071-5/+5
| | | | | | | | | | | | To avoid confusion between REQ_OP_FLUSH, which is handled by request_fn drivers, and upper layers requesting the block layer perform a flush sequence along with possibly a WRITE, this patch renames REQ_FLUSH to REQ_PREFLUSH. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* dm stats: fix spelling mistake in DocumentationEric Engestrom2016-05-051-1/+1
| | | | | Signed-off-by: Eric Engestrom <eric@engestrom.ch> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache: update cache-policies.txt now that mq is an alias for smqMike Snitzer2016-05-051-18/+16
| | | | | | | Also fix some typos and make all "smq" and "mq" references consistently lowercase. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache: make the 'mq' policy an alias for 'smq'Joe Thornber2016-03-101-37/+2
| | | | | | | | | | | | smq seems to be performing better than the old mq policy in all situations, as well as using a quarter of the memory. Make 'mq' an alias for 'smq' when choosing a cache policy. The tunables that were present for the old mq are faked, and have no effect. mq should be considered deprecated now. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm verity: add ignore_zero_blocks featureSami Tolvanen2015-12-101-0/+5
| | | | | | | | If ignore_zero_blocks is enabled dm-verity will return zeroes for blocks matching a zero hash without validating the content. Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm verity: add support for forward error correctionSami Tolvanen2015-12-101-2/+33
| | | | | | | | | | | | | | | | | | | | | | | | Add support for correcting corrupted blocks using Reed-Solomon. This code uses RS(255, N) interleaved across data and hash blocks. Each error-correcting block covers N bytes evenly distributed across the combined total data, so that each byte is a maximum distance away from the others. This makes it possible to recover from several consecutive corrupted blocks with relatively small space overhead. In addition, using verity hashes to locate erasures nearly doubles the effectiveness of error correction. Being able to detect corrupted blocks also improves performance, because only corrupted blocks need to corrected. For a 2 GiB partition, RS(255, 253) (two parity bytes for each 253-byte block) can correct up to 16 MiB of consecutive corrupted blocks if erasures can be located, and 8 MiB if they cannot, with 16 MiB space overhead. Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* Merge tag 'dm-4.4-changes' of ↵Linus Torvalds2015-11-051-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: "Smaller set of DM changes for this merge. I've based these changes on Jens' for-4.4/reservations branch because the associated DM changes required it. - Revert a dm-multipath change that caused a regression for unprivledged users (e.g. kvm guests) that issued ioctls when a multipath device had no available paths. - Include Christoph's refactoring of DM's ioctl handling and add support for passing through persistent reservations with DM multipath. - All other changes are very simple cleanups" * tag 'dm-4.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm switch: simplify conditional in alloc_region_table() dm delay: document that offsets are specified in sectors dm delay: capitalize the start of an delay_ctr() error message dm delay: Use DM_MAPIO macros instead of open-coded equivalents dm linear: remove redundant target name from error messages dm persistent data: eliminate unnecessary return values dm: eliminate unused "bioset" process for each bio-based DM device dm: convert ffs to __ffs dm: drop NULL test before kmem_cache_destroy() and mempool_destroy() dm: add support for passing through persistent reservations dm: refactor ioctl handling Revert "dm mpath: fix stalls when handling invalid ioctls" dm: initialize non-blk-mq queue data before queue is used
| * dm delay: document that offsets are specified in sectorsTomohiro Kusumi2015-11-011-0/+1
| | | | | | | | | | | | | | | | Only delay params are mentioned in delay.txt. Mention offsets just like documents for linear and flakey do. Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* | dm snapshot: add new persistent store option to support overflowMike Snitzer2015-10-091-3/+7
|/ | | | | | | | | | | | | | | Commit 76c44f6d80 introduced the possibly for "Overflow" to be reported by the snapshot device's status. Older userspace (e.g. lvm2) does not handle the "Overflow" status response. Fix this incompatibility by requiring newer userspace code, that can cope with "Overflow", request the persistent store with overflow support by using "PO" (Persistent with Overflow) for the snapshot store type. Reported-by: Zdenek Kabelac <zkabelac@redhat.com> Fixes: 76c44f6d80 ("dm snapshot: don't invalidate on-disk image on snapshot write overflow") Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm raid: document RAID 4/5/6 discard supportHeinz Mauelshagen2015-08-311-0/+31
| | | | | | | | For RAID 4/5/6 data integrity reasons 'discard_zeroes_data' must work properly. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm stats: report precise_timestamps and histogram in @stats_list outputMikulas Patocka2015-08-181-0/+4
| | | | | | | | | | | | | If the user selected the precise_timestamps or histogram options, report it in the @stats_list message output. If the user didn't select these options, no extra tokens are reported, thus it is backward compatible with old software that doesn't know about precise timestamps and histogram. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 4.2
* dm cache: display 'needs_check' in status if it is setMike Snitzer2015-07-161-0/+6
| | | | | | | | | | There is currently no way to see that the needs_check flag has been set in the metadata. Display 'needs_check' in the cache status if it is set in the cache metadata. Also, update cache documentation. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm thin: display 'needs_check' in status if it is setMike Snitzer2015-07-161-1/+8
| | | | | | | | | | There is currently no way to see that the needs_check flag has been set in the metadata. Display 'needs_check' in the thin-pool status if it is set in the thinp metadata. Also, update thinp documentation. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm stats: collect and report histogram of IO latenciesMikulas Patocka2015-06-171-3/+16
| | | | | | | | Add an option to dm statistics to collect and report a histogram of IO latencies. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm stats: support precise timestampsMikulas Patocka2015-06-171-4/+24
| | | | | | | | Make it possible to use precise timestamps with nanosecond granularity in dm statistics. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache: switch the "default" cache replacement policy from mq to smqMike Snitzer2015-06-171-3/+64
| | | | | | | | | | | | | | | | | | | The Stochastic multiqueue (SMQ) policy (vs MQ) offers the promise of less memory utilization, improved performance and increased adaptability in the face of changing workloads. SMQ also does not have any cumbersome tuning knobs. Users may switch from "mq" to "smq" simply by appropriately reloading a DM table that is using the cache target. Doing so will cause all of the mq policy's hints to be dropped. Also, performance of the cache may degrade slightly until smq recalculates the origin device's hotspots that should be cached. In the future the "mq" policy will just silently make use of "smq" and the mq code will be removed. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
* dm cache: add fail io mode and needs_check flagJoe Thornber2015-06-111-2/+7
| | | | | | | | | | | | | | | | | | | | If a cache metadata operation fails (e.g. transaction commit) the cache's metadata device will abort the current transaction, set a new needs_check flag, and the cache will transition to "read-only" mode. If aborting the transaction or setting the needs_check flag fails the cache will transition to "fail-io" mode. Once needs_check is set the cache device will not be allowed to activate. Activation requires write access to metadata. Future work is needed to add proper support for running the cache in read-only mode. Once in fail-io mode the cache will report a status of "Fail". Also, add commit() wrapper that will disallow commits if in read_only or fail mode. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm raid: add support for the MD RAID0 personalityHeinz Mauelshagen2015-05-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Add dm-raid access to the MD RAID0 personality to enable single zone striping. The following changes enable that access: - add type definition to raid_types array - make bitmap creation conditonal in super_validate(), because bitmaps are not allowed in raid0 - set rdev->sectors to the data image size in super_validate() to allow the raid0 personality to calculate the MD array size properly - use mdddev(un)lock() functions instead of direct mutex_(un)lock() (wrapped in here because it's a trivial change) - enhance raid_status() to always report full sync for raid0 so that userspace checks for 100% sync will succeed and allow for resize (and takeover/reshape once added in future paches) - enhance raid_resume() to not load bitmap in case of raid0 - add merge function to avoid data corruption (seen with readahead) that resulted from bio payloads that grew too large. This problem did not occur with the other raid levels because it either did not apply without striping (raid1) or was avoided via stripe caching. - raise version to 1.7.0 because of the raid0 API change Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Reviewed-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm raid: fixup documentation for discard supportHeinz Mauelshagen2015-05-291-0/+1
| | | | | | | | | | | | Remove comment above parse_raid_params() that claims "devices_handle_discard_safely" is a table line argument when it is actually is a module parameter. Also, backfill dm-raid target version 1.6.0 documentation. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Reviewed-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm crypt: update URLs to new cryptsetup project pageMilan Broz2015-04-152-4/+4
| | | | | | | | Cryptsetup home page moved to GitLab. Also remove link to abandonded Truecrypt page. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm: add log writes targetJosef Bacik2015-04-151-0/+140
| | | | | | | | | | | | | Introduce a new target that is meant for file system developers to test file system integrity at particular points in the life of a file system. We capture all write requests and associated data and log them to a separate device for later replay. There is a userspace utility to do this replay. The idea behind this is to give file system developers a tool to verify that the file system is always consistent. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Zach Brown <zab@zabbo.net> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm verity: add error handling modes for corrupted blocksSami Tolvanen2015-04-151-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | Add device specific modes to dm-verity to specify how corrupted blocks should be handled. The following modes are defined: - DM_VERITY_MODE_EIO is the default behavior, where reading a corrupted block results in -EIO. - DM_VERITY_MODE_LOGGING only logs corrupted blocks, but does not block the read. - DM_VERITY_MODE_RESTART calls kernel_restart when a corrupted block is discovered. In addition, each mode sends a uevent to notify userspace of corruption and to allow further recovery actions. The driver defaults to previous behavior (DM_VERITY_MODE_EIO) and other modes can be enabled with an additional parameter to the verity table. Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm thin: remove stale 'trim' message documentationMike Snitzer2015-04-151-3/+0
| | | | | | The 'trim' message wasn't ever implemented. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm switch: fix Documentation to use plain textMike Snitzer2015-03-311-2/+2
| | | | Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm crypt: add 'submit_from_crypt_cpus' optionMikulas Patocka2015-02-161-1/+9
| | | | | | | | | | | | | | | Make it possible to disable offloading writes by setting the optional 'submit_from_crypt_cpus' table argument. There are some situations where offloading write bios from the encryption threads to a single thread degrades performance significantly. The default is to offload write bios to the same thread because it benefits CFQ to have writes submitted using the same IO context. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm crypt: use unbound workqueue for request processingMikulas Patocka2015-02-161-1/+6
| | | | | | | | | | Use unbound workqueue by default so that work is automatically balanced between available CPUs. The original behavior of encrypting using the same cpu that IO was submitted on can still be enabled by setting the optional 'same_cpu_crypt' table argument. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache policy mq: simplify ability to promote sequential IO to the cacheMike Snitzer2014-11-101-5/+11
| | | | | | | | | | Before, if the user wanted sequential IO to be promoted to the cache they'd have to set sequential_threshold to some nebulous large value. Now, the user may easily disable sequential IO detection (and sequential IO's implicit bypass of the cache) by setting sequential_threshold to 0. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache policy mq: tweak algorithm that decides when to promote a blockJoe Thornber2014-11-101-3/+3
| | | | | | | | | | | | | | Rather than maintaining a separate promote_threshold variable that we periodically update we now use the hit count of the oldest clean block. Also add a fudge factor to discourage demoting dirty blocks. With some tests this has a sizeable difference, because the old code was too eager to demote blocks. For example, device-mapper-test-suite's git_extract_cache_quick test goes from taking 190 seconds, to 142 (linear on spindle takes 250). Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm switch: efficiently support repetitive patternsMikulas Patocka2014-08-011-0/+12
| | | | | | | | | | | | | | | | | | | | Add support for quickly loading a repetitive pattern into the dm-switch target. In the "set_regions_mappings" message, the user may now use "Rn,m" as one of the arguments. "n" and "m" are hexadecimal numbers. The "Rn,m" argument repeats the last "n" arguments in the following "m" slots. For example: dmsetup message switch 0 set_region_mappings 1000:1 :2 R2,10 is equivalent to dmsetup message switch 0 set_region_mappings 1000:1 :2 :1 :2 :1 :2 :1 :2 \ :1 :2 :1 :2 :1 :2 :1 :2 :1 :2 Requested-by: Jay Wang <jwang@nimblestorage.com> Tested-by: Jay Wang <jwang@nimblestorage.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm thin: add 'no_space_timeout' dm-thin-pool module paramMike Snitzer2014-05-201-1/+4
| | | | | | | | | | | | | | Commit 85ad643b ("dm thin: add timeout to stop out-of-data-space mode holding IO forever") introduced a fixed 60 second timeout. Users may want to either disable or modify this timeout. Allow the out-of-data-space timeout to be configured using the 'no_space_timeout' dm-thin-pool module param. Setting it to 0 will disable the timeout, resulting in IO being queued until more data space is added to the thin-pool. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 3.14+
* dm: add era targetJoe Thornber2014-03-271-0/+108
| | | | | | | | | | | | | | | | | dm-era is a target that behaves similar to the linear target. In addition it keeps track of which blocks were written within a user defined period of time called an 'era'. Each era target instance maintains the current era as a monotonically increasing 32-bit counter. Use cases include tracking changed blocks for backup software, and partially invalidating the contents of a cache to restore cache coherency after rolling back a vendor snapshot. dm-era is primarily expected to be paired with the dm-cache target. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm thin: fix Documentation for held metadata root featureMike Snitzer2014-03-061-3/+2
| | | | | | | | The Documentation for the thin provisioning target's held metadata root feature was incorrect. It is now available and the value for the held metadata root is in block units (not 512b sectors). Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm thin: ensure user takes action to validate data and metadata consistencyMike Snitzer2014-03-052-6/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a thin metadata operation fails the current transaction will abort, whereby causing potential for IO layers up the stack (e.g. filesystems) to have data loss. As such, set THIN_METADATA_NEEDS_CHECK_FLAG in the thin metadata's superblock which: 1) requires the user verify the thin metadata is consistent (e.g. use thin_check, etc) 2) suggests the user verify the thin data is consistent (e.g. use fsck) The only way to clear the superblock's THIN_METADATA_NEEDS_CHECK_FLAG is to run thin_repair. On metadata operation failure: abort current metadata transaction, set pool in read-only mode, and now set the needs_check flag. As part of this change, constraints are introduced or relaxed: * don't allow a pool to transition to write mode if needs_check is set * don't allow data or metadata space to be resized if needs_check is set * if a thin pool's metadata space is exhausted: the kernel will now force the user to take the pool offline for repair before the kernel will allow the metadata space to be extended. Also, update Documentation to include information about when the thin provisioning target commits metadata, how it handles metadata failures and running out of space. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Joe Thornber <ejt@redhat.com>
* dm cache: add policy name to status outputMike Snitzer2014-01-161-1/+2
| | | | | | | | | | | | | | The cache's policy may have been established using the "default" alias, which is currently the "mq" policy but the default policy may change in the future. It is useful to know exactly which policy is being used. Add a 'real' member to the dm_cache_policy_type structure and have the "default" dm_cache_policy_type point to the real "mq" dm_cache_policy_type. Update dm_cache_policy_get_name() to check if real is set, if so report the name of the real policy (not the alias). Requested-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache: add block sizes and total cache blocks to status outputMike Snitzer2014-01-101-22/+28
| | | | | | | | | | | | | | | | | | | | | | | | | Improve cache_status to emit: <metadata block size> <#used metadata blocks>/<#total metadata blocks> <cache block size> <#used cache blocks>/<#total cache blocks> ... Adding the block sizes allows for easier calculation of the overall size of both the metadata and cache devices. Adding <#total cache blocks> provides useful context for how much of the cache is used. Unfortunately these additions to the status will require updates to users' scripts that monitor the cache status. But these changes help provide more comprehensive information about the cache device and will simplify tools that are being developed to manage dm-cache devices -- because they won't need to issue 3 operations to cobble together the information that we can easily provide via a single status ioctl. While updating the status documentation in cache.txt spaces were tabify'd. Requested-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
* dm cache policy mq: introduce three promotion threshold tunablesJoe Thornber2014-01-071-2/+14
| | | | | | | | | | | | | | | | | | | | | Internally the mq policy maintains a promotion threshold variable. If the hit count of a block not in the cache goes above this threshold it gets promoted to the cache. This patch introduces three new tunables that allow you to tweak the promotion threshold by adding a small value. These adjustments depend on the io type: read_promote_adjustment: READ io, default 4 write_promote_adjustment: WRITE io, default 8 discard_promote_adjustment: READ/WRITE io to a discarded block, default 1 If you're trying to quickly warm a new cache device you may wish to reduce these to encourage promotion. Remember to switch them back to their defaults after the cache fills though. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm thin: add error_if_no_space featureMike Snitzer2014-01-071-0/+7
| | | | | | | | | | | | | If the pool runs out of data or metadata space, the pool can either queue or error the IO destined to the data device. The default is to queue the IO until more space is added. An admin may now configure the pool to error IO when no space is available by setting the 'error_if_no_space' feature when loading the thin-pool table. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
* dm cache: update Documentation for invalidate_cblocks's range syntaxMike Snitzer2013-12-101-4/+6
| | | | | | | | | | | The cache target's invalidate_cblocks message allows cache block (cblock) ranges to be expressed with: <cblock start>-<cblock end> The range's <cblock end> value is "one past the end", so the range includes <cblock start> through <cblock end>-1. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
* dm cache: resolve small nits and improve DocumentationMike Snitzer2013-11-121-10/+32
| | | | | | | | Document passthrough mode, cache shrinking, and cache invalidation. Also, use strcasecmp() and hlist_unhashed(). Reported-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache: add cache block invalidation supportJoe Thornber2013-11-111-1/+11
| | | | | | | | | | | | | | Cache block invalidation is removing an entry from the cache without writing it back. Cache blocks can be invalidated via the 'invalidate_cblocks' message, which takes an arbitrary number of cblock ranges: invalidate_cblocks [<cblock>|<cblock begin>-<cblock end>]* E.g. dmsetup message my_cache 0 invalidate_cblocks 2345 3456-4567 5678-6789 Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache: add passthrough modeJoe Thornber2013-11-111-3/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | "Passthrough" is a dm-cache operating mode (like writethrough or writeback) which is intended to be used when the cache contents are not known to be coherent with the origin device. It behaves as follows: * All reads are served from the origin device (all reads miss the cache) * All writes are forwarded to the origin device; additionally, write hits cause cache block invalidates This mode decouples cache coherency checks from cache device creation, largely to avoid having to perform coherency checks while booting. Boot scripts can create cache devices in passthrough mode and put them into service (mount cached filesystems, for example) without having to worry about coherency. Coherency that exists is maintained, although the cache will gradually cool as writes take place. Later, applications can perform coherency checks, the nature of which will depend on the type of the underlying storage. If coherency can be verified, the cache device can be transitioned to writethrough or writeback mode while still warm; otherwise, the cache contents can be discarded prior to transitioning to the desired operating mode. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Morgan Mears <Morgan.Mears@netapp.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm cache policy mq: implement writeback_work() and mq_{set,clear}_dirty()Joe Thornber2013-11-101-2/+4
| | | | | | | | | | | | | | | | There are now two multiqueues for in cache blocks. A clean one and a dirty one. writeback_work comes from the dirty one. Demotions come from the clean one. There are two benefits: - Performance improvement, since demoting a clean block is a noop. - The cache cleans itself when io load is light. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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