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2011-01-31md: don't abort checking spares as soon as one cannot be added.NeilBrown
As spares can be added manually before a reshape starts, we need to find them all to mark some of them as in_sync. Previously we would abort looking for spares when we found an unallocated spare what could not be added to the array (implying there was no room for new spares). However already-added spares could be later in the list, so we need to keep searching. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-31md: fix the test for finding spares in raid5_start_reshape.NeilBrown
As spares can be added to the array before the reshape is started, we need to find and count them when checking there are enough. The array could have been degraded, so we need to check all devices, no just those out side of the range of devices in the array before the reshape. So instead of checking the index, check the In_sync flag as that reliably tells if the device is a spare or this purpose. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-31md: simplify some 'if' conditionals in raid5_start_reshape.NeilBrown
There are two consecutive 'if' statements. if (mddev->delta_disks >= 0) .... if (mddev->delta_disks > 0) The code in the second is equally valid if delta_disks == 0, and these two statements are the only place that 'added_devices' is used. So make them a single if statement, make added_devices a local variable, and re-indent it all. No functional change. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-31md: revert change to raid_disks on failure.NeilBrown
If we try to update_raid_disks and it fails, we should put 'delta_disks' back to zero. This is important because some code, such as slot_store, assumes that delta_disks has been validated. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-25workqueue: use WQ_MEM_RECLAIM instead of WQ_RESCUERTejun Heo
WQ_RESCUER is now an internal flag and should only be used in the workqueue implementation proper. Use WQ_MEM_RECLAIM instead. This doesn't introduce any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: dm-devel@redhat.com Cc: Neil Brown <neilb@suse.de>
2011-01-14block: restore multiple bd_link_disk_holder() supportTejun Heo
Commit e09b457b (block: simplify holder symlink handling) incorrectly assumed that there is only one link at maximum. dm may use multiple links and expects block layer to track reference count for each link, which is different from and unrelated to the exclusive device holder identified by @holder when the device is opened. Remove the single holder assumption and automatic removal of the link and revive the per-link reference count tracking. The code essentially behaves the same as before commit e09b457b sans the unnecessary kobject reference count dancing. While at it, note that this facility should not be used by anyone else than the current ones. Sysfs symlinks shouldn't be abused like this and the whole thing doesn't belong in the block layer at all. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Milan Broz <mbroz@redhat.com> Cc: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Cc: Neil Brown <neilb@suse.de> Cc: linux-raid@vger.kernel.org Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dmLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (32 commits) dm: raid456 basic support dm: per target unplug callback support dm: introduce target callbacks and congestion callback dm mpath: delay activate_path retry on SCSI_DH_RETRY dm: remove superfluous irq disablement in dm_request_fn dm log: use PTR_ERR value instead of ENOMEM dm snapshot: avoid storing private suspended state dm snapshot: persistent make metadata_wq multithreaded dm: use non reentrant workqueues if equivalent dm: convert workqueues to alloc_ordered dm stripe: switch from local workqueue to system_wq dm: dont use flush_scheduled_work dm snapshot: remove unused dm_snapshot queued_bios_work dm ioctl: suppress needless warning messages dm crypt: add loop aes iv generator dm crypt: add multi key capability dm crypt: add post iv call to iv generator dm crypt: use io thread for reads only if mempool exhausted dm crypt: scale to multiple cpus dm crypt: simplify compatible table output ...
2011-01-13Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds
* 'for-linus' of git://neil.brown.name/md: md: Fix removal of extra drives when converting RAID6 to RAID5 md: range check slot number when manually adding a spare. md/raid5: handle manually-added spares in start_reshape. md: fix sync_completed reporting for very large drives (>2TB) md: allow suspend_lo and suspend_hi to decrease as well as increase. md: Don't let implementation detail of curr_resync leak out through sysfs. md: separate meta and data devs md-new-param-to_sync_page_io md-new-param-to-calc_dev_sboffset md: Be more careful about clearing flags bit in ->recovery md: md_stop_writes requires mddev_lock. md/raid5: use sysfs_notify_dirent_safe to avoid NULL pointer md: Ensure no IO request to get md device before it is properly initialised. md: Fix single printks with multiple KERN_<level>s md: fix regression resulting in delays in clearing bits in a bitmap md: fix regression with re-adding devices to arrays with no metadata
2011-01-14md: Fix removal of extra drives when converting RAID6 to RAID5NeilBrown
When a RAID6 is converted to a RAID5, the extra drive should be discarded. However it isn't due to a typo in a comparison. This bug was introduced in commit e93f68a1fc6 in 2.6.35-rc4 and is suitable for any -stable since than. As the extra drive is not removed, the 'degraded' counter is wrong and so the RAID5 will not respond correctly to a subsequent failure. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md: range check slot number when manually adding a spare.NeilBrown
When adding a spare to an active array, we should check the slot number, but allow it to be larger than raid_disks if a reshape is being prepared. Apply the same test when adding a device to an array-under-construction. It already had most of the test in place, but not quite all. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md/raid5: handle manually-added spares in start_reshape.NeilBrown
It is possible to manually add spares to specific slots before starting a reshape. raid5_start_reshape should recognised this possibility and include it in the accounting. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md: fix sync_completed reporting for very large drives (>2TB)Rémi Rérolle
The values exported in the sync_completed file are unsigned long, which overflows with very large drives, resulting in wrong values reported. Since sync_completed uses sectors as unit, we'll start getting wrong values with components larger than 2TB. This patch simply replaces the use of unsigned long by unsigned long long. Signed-off-by: Rémi Rérolle <rrerolle@lacie.com> Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md: allow suspend_lo and suspend_hi to decrease as well as increase.NeilBrown
The sysfs attributes 'suspend_lo' and 'suspend_hi' describe a region to which read/writes are suspended so that the under lying data can be manipulated without user-space noticing. Currently the window they describe can only move forwards along the device. However this is an unnecessary restriction which will cause problems with planned developments. So relax this restriction and allow these endpoints to move arbitrarily. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md: Don't let implementation detail of curr_resync leak out through sysfs.NeilBrown
mddev->curr_resync has artificial values of '1' and '2' which are used by the code which ensures only one resync is happening at a time on any given device. These values are internal and should never be exposed to user-space (except when translated appropriately as in the 'pending' status in /proc/mdstat). Unfortunately they are as ->curr_resync is assigned to ->curr_resync_completed and that value is directly visible through sysfs. So change the assignments to ->curr_resync_completed to get the same valued from elsewhere in a form that doesn't have the magic '1' or '2' values. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md: separate meta and data devsJonathan Brassow
Allow the metadata to be on a separate device from the data. This doesn't mean the data and metadata will by on separate physical devices - it simply gives device-mapper and userspace tools more flexibility. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md-new-param-to_sync_page_ioJonathan Brassow
Add new parameter to 'sync_page_io'. The new parameter allows us to distinguish between metadata and data operations. This becomes important later when we add the ability to use separate devices for data and metadata. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
2011-01-14md-new-param-to-calc_dev_sboffsetJonathan Brassow
When we allow for separate devices for data and metadata in a later patch, we will need to be able to calculate the superblock offset based on more than the bdev. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
2011-01-14md: Be more careful about clearing flags bit in ->recoveryNeilBrown
Setting ->recovery to 0 is generally not a good idea as it could clear bits that shouldn't be cleared. In particular, MD_RECOVERY_FROZEN should only be cleared on explicit request from user-space. So when we need to clear things, just clear the bits that need clearing. As there are a few different places which reap a resync process - and some do an incomplte job - factor out the code for doing the from md_check_recovery and call that function instead of open coding part of it. Signed-off-by: NeilBrown <neilb@suse.de> Reported-by: Jonathan Brassow <jbrassow@redhat.com>
2011-01-14md: md_stop_writes requires mddev_lock.NeilBrown
As md_stop_writes manipulates the sync_thread and calls md_update_sb, it need to be called with mddev_lock held. In all internal cases it is, but the symbol is exported for dm-raid to call and in that case the lock won't be help. Do make an exported version which takes the lock, and an internal version which does not. Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md/raid5: use sysfs_notify_dirent_safe to avoid NULL pointerJonathan Brassow
With the module parameter 'start_dirty_degraded' set, raid5_spare_active() previously called sysfs_notify_dirent() with a NULL argument (rdev->sysfs_state) when a rebuild finished. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2011-01-14md: Ensure no IO request to get md device before it is properly initialised.NeilBrown
When an md device is in the process of coming on line it is possible for an IO request (typically a partition table probe) to get through before the array is fully initialised, which can cause unexpected behaviour (e.g. a crash). So explicitly record when the array is ready for IO and don't allow IO through until then. There is no possibility for a similar problem when the array is going off-line as there must only be one 'open' at that time, and it is busy off-lining the array and so cannot send IO requests. So no memory barrier is needed in md_stop() This has been a bug since commit 409c57f3801 in 2.6.30 which introduced md_make_request. Before then, each personality would register its own make_request_fn when it was ready. This is suitable for any stable kernel from 2.6.30.y onwards. Cc: <stable@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de> Reported-by: "Hawrylewicz Czarnowski, Przemyslaw" <przemyslaw.hawrylewicz.czarnowski@intel.com>
2011-01-14md: Fix single printks with multiple KERN_<level>sJoe Perches
Noticed-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-14md: fix regression resulting in delays in clearing bits in a bitmapNeilBrown
commit 589a594be1fb (2.6.37-rc4) fixed a problem were md_thread would sometimes call the ->run function at a bad time. If an error is detected during array start up after the md_thread has been started, the md_thread is killed. This resulted in the ->run function being called once. However the array may not be in a state that it is safe to call ->run. However the fix imposed meant that ->run was not called on a timeout. This means that when an array goes idle, bitmap bits do not get cleared promptly. While the array is busy the bits will still be cleared when appropriate so this is not very serious. There is no risk to data. Change the test so that we only avoid calling ->run when the thread is being stopped. This more explicitly addresses the problem situation. This is suitable for 2.6.37-stable and any -stable kernel to which 589a594be1fb was applied. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
2011-01-13dm: raid456 basic supportNeilBrown
This patch is the skeleton for the DM target that will be the bridge from DM to MD (initially RAID456 and later RAID1). It provides a way to use device-mapper interfaces to the MD RAID456 drivers. As with all device-mapper targets, the nominal public interfaces are the constructor (CTR) tables and the status outputs (both STATUSTYPE_INFO and STATUSTYPE_TABLE). The CTR table looks like the following: 1: <s> <l> raid \ 2: <raid_type> <#raid_params> <raid_params> \ 3: <#raid_devs> <meta_dev1> <dev1> .. <meta_devN> <devN> Line 1 contains the standard first three arguments to any device-mapper target - the start, length, and target type fields. The target type in this case is "raid". Line 2 contains the arguments that define the particular raid type/personality/level, the required arguments for that raid type, and any optional arguments. Possible raid types include: raid4, raid5_la, raid5_ls, raid5_rs, raid6_zr, raid6_nr, and raid6_nc. (again, raid1 is planned for the future.) The list of required and optional parameters is the same for all the current raid types. The required parameters are positional, while the optional parameters are given as key/value pairs. The possible parameters are as follows: <chunk_size> Chunk size in sectors. [[no]sync] Force/Prevent RAID initialization [rebuild <idx>] Rebuild the drive indicated by the index [daemon_sleep <ms>] Time between bitmap daemon work to clear bits [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization [max_write_behind <value>] See '-write-behind=' (man mdadm) [stripe_cache <sectors>] Stripe cache size for higher RAIDs Line 3 contains the list of devices that compose the array in metadata/data device pairs. If the metadata is stored separately, a '-' is given for the metadata device position. If a drive has failed or is missing at creation time, a '-' can be given for both the metadata and data drives for a given position. Examples: # RAID4 - 4 data drives, 1 parity # No metadata devices specified to hold superblock/bitmap info # Chunk size of 1MiB # (Lines separated for easy reading) 0 1960893648 raid \ raid4 1 2048 \ 5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81 # RAID4 - 4 data drives, 1 parity (no metadata devices) # Chunk size of 1MiB, force RAID initialization, # min recovery rate at 20 kiB/sec/disk 0 1960893648 raid \ raid4 4 2048 min_recovery_rate 20 sync\ 5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81 Performing a 'dmsetup table' should display the CTR table used to construct the mapping (with possible reordering of optional parameters). Performing a 'dmsetup status' will yield information on the state and health of the array. The output is as follows: 1: <s> <l> raid \ 2: <raid_type> <#devices> <1 health char for each dev> <resync_ratio> Line 1 is standard DM output. Line 2 is best shown by example: 0 1960893648 raid raid4 5 AAAAA 2/490221568 Here we can see the RAID type is raid4, there are 5 devices - all of which are 'A'live, and the array is 2/490221568 complete with recovery. Cc: linux-raid@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: per target unplug callback supportNeilBrown
Add per-target unplug callback support. Cc: linux-raid@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: introduce target callbacks and congestion callbackNeilBrown
DM currently implements congestion checking by checking on congestion in each component device. For raid456 we need to also check if the stripe cache is congested. Add per-target congestion checker callback support. Extending the target_callbacks structure with additional callback functions allows for establishing multiple callbacks per-target (a callback is also needed for unplug). Cc: linux-raid@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm mpath: delay activate_path retry on SCSI_DH_RETRYChandra Seetharaman
This patch adds a user-configurable 'pg_init_delay_msecs' feature. Use this feature to specify the number of milliseconds to delay before retrying scsi_dh_activate, when SCSI_DH_RETRY is returned. SCSI Device Handlers return SCSI_DH_IMM_RETRY if we could retry activation immediately and SCSI_DH_RETRY in cases where it is better to retry after some delay. Currently we immediately retry scsi_dh_activate irrespective of SCSI_DH_IMM_RETRY and SCSI_DH_RETRY. The 'pg_init_delay_msecs' feature may be provided during table create or load, e.g.: dmsetup create --table "0 20971520 multipath 3 queue_if_no_path \ pg_init_delay_msecs 2500 ..." mpatha The default for 'pg_init_delay_msecs' is 2000 milliseconds. Maximum configurable delay is 60000 milliseconds. Specifying a 'pg_init_delay_msecs' of 0 will cause immediate retry. Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com> Acked-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: remove superfluous irq disablement in dm_request_fnKiyoshi Ueda
This patch changes spin_lock_irq() to spin_lock() in dm_request_fn(). This patch is just a clean-up and no functional change. The spin_lock_irq() was leftover from the early request-based dm code, where map_request() used to enable interrupts. Since current map_request() never enables interrupts, we can change it to spin_lock() to match the prior spin_unlock(). Auditing through the dm and block-layer code called from map_request(), I confirmed all functions save/restore interrupt status, so no function returning with interrupts enabled. Also I haven't observed any problem on my test environment which uses scsi and lpfc driver after heavy I/O testing with occasional path down/up. Added BUG_ON() to detect breakage in future. Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm log: use PTR_ERR value instead of ENOMEMDan Carpenter
It's nicer to return the PTR_ERR() value instead of just returning -ENOMEM. In the current code the PTR_ERR() value is always equal to -ENOMEM so this doesn't actually affect anything, but still... In addition, dm_dirty_log_create() doesn't check for a specific -ENOMEM return. So this change is safe relative to potential for a non -ENOMEM return in the future. Signed-off-by: Dan Carpenter <error27@gmail.com> Acked-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm snapshot: avoid storing private suspended stateMike Snitzer
Use dm_suspended() rather than having each snapshot target maintain a private 'suspended' flag in struct dm_snapshot. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm snapshot: persistent make metadata_wq multithreadedTejun Heo
metadata_wq serves on-stack work items from chunk_io(). Even if multiple chunk_io() are simultaneously in progress, each is independent and queued only once, so multithreaded workqueue can be safely used. Switch metadata_wq to multithread and flush the work item instead of the workqueue in chunk_io(). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: use non reentrant workqueues if equivalentTejun Heo
kmirrord_wq, kcopyd_work and md->wq are created per dm instance and serve only a single work item from the dm instance, so non-reentrant workqueues would provide the same ordering guarantees as ordered ones while allowing CPU affinity and use of the workqueues for other purposes. Switch them to non-reentrant workqueues. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: convert workqueues to alloc_orderedTejun Heo
Convert all create[_singlethread]_work() users to the new alloc[_ordered]_workqueue(). This conversion is mechanical and doesn't introduce any behavior change. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm stripe: switch from local workqueue to system_wqTejun Heo
kstriped only serves sc->kstriped_ws which runs dm_table_event(). This doesn't need to be executed from an ordered workqueue w/ rescuer. Drop kstriped and use the system_wq instead. While at it, rename kstriped_ws to trigger_event so that it's consistent with other dm modules. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: dont use flush_scheduled_workTejun Heo
flush_scheduled_work() is being deprecated. Flush the used work directly instead. In all dm targets, the only work which uses system_wq is ->trigger_event. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm snapshot: remove unused dm_snapshot queued_bios_workTejun Heo
dm_snapshot->queued_bios_work isn't used. Remove ->queued_bios[_work] from dm_snapshot structure, the flush_queued_bios work function and ksnapd workqueue. The DM snapshot changes that were going to use the ksnapd workqueue were either superseded (fix for origin write races) or never completed (deallocation of invalid snapshot's memory via workqueue). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm ioctl: suppress needless warning messagesMilan Broz
The device-mapper should not send warning messages to syslog if a device is not found. This can be done by userspace according to the returned dm-ioctl error code. So move these messages to debug level and use rate limiting to not flood syslog. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: add loop aes iv generatorMilan Broz
This patch adds a compatible implementation of the block chaining mode used by the Loop-AES block device encryption system (http://loop-aes.sourceforge.net/) designed by Jari Ruusu. It operates on full 512 byte sectors and uses CBC with an IV derived from the sector number, the data and optionally extra IV seed. This means that after CBC decryption the first block of sector must be tweaked according to decrypted data. Loop-AES can use three encryption schemes: version 1: is plain aes-cbc mode (already compatible) version 2: uses 64 multikey scheme with own IV generator version 3: the same as version 2 with additional IV seed (it uses 65 keys, last key is used as IV seed) The IV generator is here named lmk (Loop-AES multikey) and for the cipher specification looks like: aes:64-cbc-lmk Version 2 and 3 is recognised according to length of provided multi-key string (which is just hexa encoded "raw key" used in original Loop-AES ioctl). Configuration of the device and decoding key string will be done in userspace (cryptsetup). (Loop-AES stores keys in gpg encrypted file, raw keys are output of simple hashing of lines in this file). Based on an implementation by Max Vozeler: http://article.gmane.org/gmane.linux.kernel.cryptoapi/3752/ Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> CC: Max Vozeler <max@hinterhof.net>
2011-01-13dm crypt: add multi key capabilityMilan Broz
This patch adds generic multikey handling to be used in following patch for Loop-AES mode compatibility. This patch extends mapping table to optional keycount and implements generic multi-key capability. With more keys defined the <key> string is divided into several <keycount> sections and these are used for tfms. The tfm is used according to sector offset (sector 0->tfm[0], sector 1->tfm[1], sector N->tfm[N modulo keycount]) (only power of two values supported for keycount here). Because of tfms per-cpu allocation, this mode can be take a lot of memory on large smp systems. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: Max Vozeler <max@hinterhof.net>
2011-01-13dm crypt: add post iv call to iv generatorMilan Broz
IV (initialisation vector) can in principle depend not only on sector but also on plaintext data (or other attributes). Change IV generator interface to work directly with dmreq structure to allow such dependence in generator. Also add post() function which is called after the crypto operation. This allows tricky modification of decrypted data or IV internals. In asynchronous mode the post() can be called after ctx->sector count was increased so it is needed to add iv_sector copy directly to dmreq structure. (N.B. dmreq always include only one sector in scatterlists) Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: use io thread for reads only if mempool exhaustedMilan Broz
If there is enough memory, code can directly submit bio instead queing this operation in separate thread. Try to alloc bio clone with GFP_NOWAIT and only if it fails use separate queue (map function cannot block here). Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: scale to multiple cpusAndi Kleen
Currently dm-crypt does all the encryption work for a single dm-crypt mapping in a single workqueue. This does not scale well when multiple CPUs are submitting IO at a high rate. The single CPU running the single thread cannot keep up with the encryption and encrypted IO performance tanks. This patch changes the crypto workqueue to be per CPU. This means that as long as the IO submitter (or the interrupt target CPUs for reads) runs on different CPUs the encryption work will be also parallel. To avoid a bottleneck on the IO worker I also changed those to be per-CPU threads. There is still some shared data, so I suspect some bouncing cache lines. But I haven't done a detailed study on that yet. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: simplify compatible table outputMilan Broz
Rename cc->cipher_mode to cc->cipher_string and store the whole of the cipher information so it can easily be printed when processing the DM_DEV_STATUS ioctl. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm log userspace: add version number to commsJonathan Brassow
This patch adds a 'version' field to the 'dm_ulog_request' structure. The 'version' field is taken from a portion of the unused 'padding' field in the 'dm_ulog_request' structure. This was done to avoid changing the size of the structure and possibly disrupting backwards compatibility. The version number will help notify user-space daemons when a change has been made to the kernel/userspace log API. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm log userspace: group clear and mark requestsJonathan Brassow
Allow the device-mapper log's 'mark' and 'clear' requests to be grouped and processed in a batch. This can significantly reduce the amount of traffic going between the kernel and userspace (where the processing daemon resides). Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm log userspace: split flush queueJonathan Brassow
Split the 'flush_list', which contained a mix of both 'mark' and 'clear' requests, into two distinct lists ('mark_list' and 'clear_list'). The device mapper log implementations (used by various DM targets) are allowed to cache 'mark' and 'clear' requests until a 'flush' is received. Until now, these cached requests were kept in the same list. They will now be put into distinct lists to facilitate group processing of these requests (in the next patch). Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm kcopyd: delay unpluggingMikulas Patocka
Make kcopyd merge more I/O requests by using device unplugging. Without this patch, each I/O request is dispatched separately to the device. If the device supports tagged queuing, there are many small requests sent to the device. To improve performance, this patch will batch as many requests as possible, allowing the queue to merge consecutive requests, and send them to the device at once. In my tests (15k SCSI disk), this patch improves sequential write throughput: Sequential write throughput (chunksize of 4k, 32k, 512k) unpatched: 15.2, 18.5, 17.5 MB/s patched: 14.4, 22.6, 23.0 MB/s In most common uses (snapshot or two-way mirror), kcopyd is only used for two devices, one for reading and the other for writing, thus this optimization is implemented only for two devices. The optimization may be extended to n-way mirrors with some code complexity increase. We keep track of two block devices to unplug (one for read and the other for write) and unplug them when exiting "do_work" thread. If there are more devices used (in theory it could happen, in practice it is rare), we unplug immediately. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm log userspace: trap all failed log construction errorsJonathan Brassow
When constructing a mirror log, it is possible for the initial request to fail for other reasons besides -ESRCH. These must be handled too. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: set key size earlyMilan Broz
Simplify key size verification (hexadecimal string) and set key size early in constructor. (Patch required by later changes.) Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: remove dm_mutex after bkl conversionMilan Broz
This patch replaces dm_mutex with _minor_lock in dm_blk_close() and then removes it. During the BKL conversion, commit 6e9624b8caec290d28b4c6d9ec75749df6372b87 (block: push down BKL into .open and .release) pushed lock_kernel() down into dm_blk_open/close calls. Commit 2a48fc0ab24241755dc93bfd4f01d68efab47f5a (block: autoconvert trivial BKL users to private mutex) converted it to a local mutex, but _minor_lock is sufficient. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>