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* Merge tag 'for-4.12/dm-changes' of ↵Linus Torvalds2017-05-033-6/+260
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * dm integrity: support larger block sizesMikulas Patocka2017-04-241-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The DM integrity block size can now be 512, 1k, 2k or 4k. Using larger blocks reduces metadata handling overhead. The block size can be configured at table load time using the "block_size:<value>" option; where <value> is expressed in bytes (defult is still 512 bytes). It is safe to use larger block sizes with DM integrity, because the DM integrity journal makes sure that the whole block is updated atomically even if the underlying device doesn't support atomic writes of that size (e.g. 4k block ontop of a 512b device). Depends-on: 2859323e ("block: fix blk_integrity_register to use template's interval_exp if not 0") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm integrity: various small changes and cleanupsMikulas Patocka2017-04-241-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some coding style changes. Fix a bug that the array test_tag has insufficient size if the digest size of internal has is bigger than the tag size. The function __fls is undefined for zero argument, this patch fixes undefined behavior if the user sets zero interleave_sectors. Fix the limit of optional arguments to 8. Don't allocate crypt_data on the stack to avoid a BUG with debug kernel. Rename all optional argument names to have underscores rather than dashes. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm raid: add raid4/5/6 journal write-back support via journal_mode optionHeinz Mauelshagen2017-03-271-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 63c32ed4afc ("dm raid: add raid4/5/6 journaling support") added journal support to close the raid4/5/6 "write hole" -- in terms of writethrough caching. Introduce a "journal_mode" feature and use the new r5c_journal_mode_set() API to add support for switching the journal device's cache mode between write-through (the current default) and write-back. NOTE: If the journal device is not layered on resilent storage and it fails, write-through mode will cause the "write hole" to reoccur. But if the journal fails while in write-back mode it will cause data loss for any dirty cache entries unless resilent storage is used for the journal. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm raid: fix table line argument order in statusHeinz Mauelshagen2017-03-271-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 3a1c1ef2f ("dm raid: enhance status interface and fixup takeover/raid0") added new table line arguments and introduced an ordering flaw. The sequence of the raid10_copies and raid10_format raid parameters got reversed which causes lvm2 userspace to fail by falsely assuming a changed table line. Sequence those 2 parameters as before so that old lvm2 can function properly with new kernels by adjusting the table line output as documented in Documentation/device-mapper/dm-raid.txt. Also, add missing version 1.10.1 highlight to the documention. Fixes: 3a1c1ef2f ("dm raid: enhance status interface and fixup takeover/raid0") Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm integrity: add recovery modeMikulas Patocka2017-03-241-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | In recovery mode, we don't: - replay the journal - check checksums - allow writes to the device This mode can be used as a last resort for data recovery. The motivation for recovery mode is that when there is a single error in the journal, the user should not lose access to the whole device. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm crypt: optionally support larger encryption sector sizeMilan Broz2017-03-241-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add optional "sector_size" parameter that specifies encryption sector size (atomic unit of block device encryption). Parameter can be in range 512 - 4096 bytes and must be power of two. For compatibility reasons, the maximal IO must fit into the page limit, so the limit is set to the minimal page size possible (4096 bytes). NOTE: this device cannot yet be handled by cryptsetup if this parameter is set. IV for the sector is calculated from the 512 bytes sector offset unless the iv_large_sectors option is used. Test script using dmsetup: DEV="/dev/sdb" DEV_SIZE=$(blockdev --getsz $DEV) KEY="9c1185a5c5e9fc54612808977ee8f548b2258d31ddadef707ba62c166051b9e3cd0294c27515f2bccee924e8823ca6e124b8fc3167ed478bca702babe4e130ac" BLOCK_SIZE=4096 # dmsetup create test_crypt --table "0 $DEV_SIZE crypt aes-xts-plain64 $KEY 0 $DEV 0 1 sector_size:$BLOCK_SIZE" # dmsetup table --showkeys test_crypt Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm crypt: introduce new format of cipher with "capi:" prefixMilan Broz2017-03-241-17/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm crypt: add cryptographic data integrity protection (authenticated encryption)Milan Broz2017-03-241-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm: add integrity targetMikulas Patocka2017-03-241-0/+189
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The dm-integrity target emulates a block device that has additional per-sector tags that can be used for storing integrity information. A general problem with storing integrity tags with every sector is that writing the sector and the integrity tag must be atomic - i.e. in case of crash, either both sector and integrity tag or none of them is written. To guarantee write atomicity the dm-integrity target uses a journal. It writes sector data and integrity tags into a journal, commits the journal and then copies the data and integrity tags to their respective location. The dm-integrity target can be used with the dm-crypt target - in this situation the dm-crypt target creates the integrity data and passes them to the dm-integrity target via bio_integrity_payload attached to the bio. In this mode, the dm-crypt and dm-integrity targets provide authenticated disk encryption - if the attacker modifies the encrypted device, an I/O error is returned instead of random data. The dm-integrity target can also be used as a standalone target, in this mode it calculates and verifies the integrity tag internally. In this mode, the dm-integrity target can be used to detect silent data corruption on the disk or in the I/O path. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* | Documentation: device-mapper: cache.txt: Fix typossayli karnik2017-03-191-1/+1
|/ | | | | | | Fix a spelling error (hexidecimal->hexadecimal). Signed-off-by: sayli karnik <karniksayli1995@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* scripts/spelling.txt: add "explictely" pattern and fix typo instancesMasahiro Yamada2017-02-271-1/+1
| | | | | | | | | | | Fix typos and add the following to the scripts/spelling.txt: explictely||explicitly Link: http://lkml.kernel.org/r/1481573103-11329-25-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dm cache metadata: add "metadata2" featureJoe Thornber2017-02-161-0/+4
| | | | | | | | | If "metadata2" is provided as a table argument when creating/loading a cache target a more compact metadata format, with separate dirty bits, is used. "metadata2" improves speed of shutting down a cache target. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm raid: add raid4/5/6 journaling supportHeinz Mauelshagen2017-01-251-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add md raid4/5/6 journaling support (upstream commit bac624f3f86a started the implementation) which closes the write hole (i.e. non-atomic updates to stripes) using a dedicated journal device. Background: raid4/5/6 stripes hold N data payloads per stripe plus one parity raid4/5 or two raid6 P/Q syndrome payloads in an in-memory stripe cache. Parity or P/Q syndromes used to recover any data payloads in case of a disk failure are calculated from the N data payloads and need to be updated on the different component devices of the raid device. Those are non-atomic, persistent updates. Hence a crash can cause failure to update all stripe payloads persistently and thus cause data loss during stripe recovery. This problem gets addressed by writing whole stripe cache entries (together with journal metadata) to a persistent journal entry on a dedicated journal device. Only if that journal entry is written successfully, the stripe cache entry is updated on the component devices of the raid device (i.e. writethrough type). In case of a crash, the entry can be recovered from the journal and be written again thus ensuring consistent stripe payload suitable to data recovery. Future dependencies: once writeback caching being worked on to compensate for the throughput implictions involved with writethrough overhead is supported with journaling in upstream, an additional patch based on this one will support it in dm-raid. Journal resilience related remarks: because stripes are recovered from the journal in case of a crash, the journal device better be resilient. Resilience becomes mandatory with future writeback support, because loosing the working set in the log means data loss as oposed to writethrough, were the loss of the journal device 'only' reintroduces the write hole. Fix comment on data offsets in parse_dev_params() and initialize new_data_offset as well. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm raid: fix transient device failure processingHeinz Mauelshagen2017-01-251-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fix addresses the following 3 failure scenarios: 1) If a (transiently) inaccessible metadata device is being passed into the constructor (e.g. a device tuple '254:4 254:5'), it is processed as if '- -' was given. This erroneously results in a status table line containing '- -', which mistakenly differs from what has been passed in. As a result, userspace libdevmapper puts the device tuple seperate from the RAID device thus not processing the dependencies properly. 2) False health status char 'A' instead of 'D' is emitted on the status status info line for the meta/data device tuple in this metadata device failure case. 3) If the metadata device is accessible when passed into the constructor but the data device (partially) isn't, that leg may be set faulty by the raid personality on access to the (partially) unavailable leg. Restore tried in a second raid device resume on such failed leg (status char 'D') fails after the (partial) leg returned. Fixes for aforementioned failure scenarios: - don't release passed in devices in the constructor thus allowing the status table line to e.g. contain '254:4 254:5' rather than '- -' - emit device status char 'D' rather than 'A' for the device tuple with the failed metadata device on the status info line - when attempting to restore faulty devices in a second resume, allow the device hot remove function to succeed by setting the device to not in-sync In case userspace intentionally passes '- -' into the constructor to avoid that device tuple (e.g. to split off a raid1 leg temporarily for later re-addition), the status table line will correctly show '- -' and the status info line will provide a '-' device health character for the non-defined device tuple. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* 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 Mauelshagen2016-06-141-3/+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 Torvalds2015-11-041-0/+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 Kusumi2015-10-311-0/+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>
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