Commit Graph

65 Commits

Author SHA1 Message Date
Mike Snitzer
c64d240df3 dm: fix Kconfig indentation
Since DM_DEBUG_BLOCK_STACK_TRACING is a DM_PERSISTENT_DATA config option
move it from drivers/md/Kconfig to drivers/md/persistent-data/Kconfig.

Doing so fixes indentation for other DM config options.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-03-03 17:31:07 -05:00
Mikulas Patocka
2995fa78e4 dm sysfs: fix a module unload race
This reverts commit be35f48610 ("dm: wait until embedded kobject is
released before destroying a device") and provides an improved fix.

The kobject release code that calls the completion must be placed in a
non-module file, otherwise there is a module unload race (if the process
calling dm_kobject_release is preempted and the DM module unloaded after
the completion is triggered, but before dm_kobject_release returns).

To fix this race, this patch moves the completion code to dm-builtin.c
which is always compiled directly into the kernel if BLK_DEV_DM is
selected.

The patch introduces a new dm_kobject_holder structure, its purpose is
to keep the completion and kobject in one place, so that it can be
accessed from non-module code without the need to export the layout of
struct mapped_device to that code.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2014-01-14 23:23:04 -05:00
Mikulas Patocka
55494bf294 dm snapshot: use dm-bufio
Use dm-bufio for initial loading of the exceptions.
Introduce a new function dm_bufio_forget that frees the given buffer.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-14 23:23:02 -05:00
Mike Snitzer
10343180f5 dm persistent data: cleanup dm-thin specific references in text
DM's persistent-data library is now used my multiple targets so
exclusive references to "pool" or "thin provisioning" need to be
cleaned up.  Adjust Kconfig's DM_DEBUG_BLOCK_STACK_TRACING text
and remove "pool" from a block manager error message.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-07 10:11:54 -05:00
Mikulas Patocka
5442851edb dm: fix Kconfig menu indentation
The option DM_LOG_USERSPACE is sub-option of DM_MIRROR, so place it
right after DM_MIRROR.  Doing so fixes various other Device mapper
targets/features to be properly nested under "Device mapper support".

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-11-09 18:20:22 -05:00
Jim Ramsay
9d0eb0ab43 dm: add switch target
dm-switch is a new target that maps IO to underlying block devices
efficiently when there is a large number of fixed-sized address regions
but there is no simple pattern to allow for a compact mapping
representation such as dm-stripe.

Though we have developed this target for a specific storage device, Dell
EqualLogic, we have made an effort to keep it as general purpose as
possible in the hope that others may benefit.

Originally developed by Jim Ramsay. Simplified by Mikulas Patocka.

Signed-off-by: Jim Ramsay <jim_ramsay@dell.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-07-10 23:41:19 +01:00
Kent Overstreet
cafe563591 bcache: A block layer cache
Does writethrough and writeback caching, handles unclean shutdown, and
has a bunch of other nifty features motivated by real world usage.

See the wiki at http://bcache.evilpiepirate.org for more.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-03-23 16:11:31 -07:00
Linus Torvalds
a5e0d73163 md updates for 3.9
mostly little bugfixes.
 Only "feature" is a new RAID10 layout which slightly
 improves the number of sets of devices that can concurrently
 fail, without data loss.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.19 (GNU/Linux)
 
 iQIVAwUAUTPm+znsnt1WYoG5AQLLsw/+PMqr8roC4twgxTWV1NRbU8NtOcRi9Rj9
 uvBS63uYAaLdi/D3UBKFYczmNCu9knuXbcp9SgFDxH7LlthQsWN/GYnif06pPo3w
 9Agu5M8c062TJEG1vrnX6FhPO6pNgrWFr3h+CKkTiD3179i9DoQpP8LXQToeyMtI
 YRMQf/zCkxYtDvWAP0iwsEWtw8cf+q9I/uGPhQ1L+DnZapXYdbtnqWBRz9q6mrDt
 orcGrP41aZHvnOHUaTbwmaorCKkf/Ys4SMaGenrSFpnpQMypt7VgNuwHC59LxvJT
 5eiFG/26zIsv7Wk0jv/TvFP5qzUPo0/PFkd5ug0ArvbVRiXS2cMJDwQvMdO1toxD
 i5Bb+P9DptadvoWhOTgIpxnG77yRH45wJvyJOk+ZfS1/IO87nCRa3d0yiNOU5e2/
 o0VdXPZRr72sdKKTK6kQuYfwCPb+Z2Pz6Q8BJdk6GxlmTXyP6sKhIgwUX86534fE
 LrOxfK8qV+GetVu3X02RoX2CyJJRQHXyXmbHuSzXuo/JiOYtDigAydwNZChvf+tf
 OoMY9K8vgNbhnGsUG6la7XPvZ+6dZMjdnxp2HB99Ml5A3PWZd75i5T6IHHxIQFbD
 C3z9PWTWP+hK4k15DEyjlELtsE9WduGTXG4kUcf328xJ/7lj4VIImVugdCz+1B6z
 +HlI6BiLwzY=
 =YdVD
 -----END PGP SIGNATURE-----

Merge tag 'md-3.9' of git://neil.brown.name/md

Pull md updates from NeilBrown:
 "Mostly little bugfixes.

  Only "feature" is a new RAID10 layout which slightly improves the
  number of sets of devices that can concurrently fail, without data
  loss."

* tag 'md-3.9' of git://neil.brown.name/md:
  md: expedite metadata update when switching  read-auto -> active
  md: remove CONFIG_MULTICORE_RAID456
  md/raid1,raid10: fix deadlock with freeze_array()
  md/raid0: improve error message when converting RAID4-with-spares to RAID0
  md: raid0: fix error return from create_stripe_zones.
  md: fix two bugs when attempting to resize RAID0 array.
  DM RAID: Add support for MD's RAID10 "far" and "offset" algorithms
  MD RAID10: Improve redundancy for 'far' and 'offset' algorithms (part 2)
  MD RAID10: Improve redundancy for 'far' and 'offset' algorithms (part 1)
  MD RAID10: Minor non-functional code changes
  md: raid1,10: Handle REQ_WRITE_SAME flag in write bios
  md: protect against crash upon fsync on ro array
2013-03-05 17:22:08 -08:00
Heinz Mauelshagen
8735a81347 dm cache: add cleaner policy
A simple cache policy that writes back all data to the origin.

This is used to decommission a dm cache by emptying it.

Signed-off-by: Heinz Mauelshagen <mauelshagen@redhat.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-01 22:45:52 +00:00
Joe Thornber
f283635281 dm cache: add mq policy
A cache policy that uses a multiqueue ordered by recent hit
count to select which blocks should be promoted and demoted.
This is meant to be a general purpose policy.  It prioritises
reads over writes.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-01 22:45:51 +00:00
Joe Thornber
c6b4fcbad0 dm: add cache target
Add a target that allows a fast device such as an SSD to be used as a
cache for a slower device such as a disk.

A plug-in architecture was chosen so that the decisions about which data
to migrate and when are delegated to interchangeable tunable policy
modules.  The first general purpose module we have developed, called
"mq" (multiqueue), follows in the next patch.  Other modules are
under development.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Heinz Mauelshagen <mauelshagen@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-01 22:45:51 +00:00
Alasdair G Kergon
d57916a00f dm: remove CONFIG_EXPERIMENTAL
Remove EXPERIMENTAL from all existing device-mapper targets.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-01 22:45:46 +00:00
NeilBrown
51acbcec6c md: remove CONFIG_MULTICORE_RAID456
This doesn't seem to actually help and we have an alternate
multi-threading approach waiting in the wings, so just get
rid of this config option and associated code.

As a bonus, we remove one use of CONFIG_EXPERIMENTAL

Cc: Dan Williams <djbw@fb.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: NeilBrown <neilb@suse.de>
2013-02-28 09:08:34 +11:00
Mike Snitzer
4f81a41762 dm thin: move bio_prison code to separate module
The bio prison code will be useful to other future DM targets so
move it to a separate module.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-10-12 21:02:13 +01:00
Linus Torvalds
25aa6a7ae4 Additional md update for 3.6
This contains a few patches that depend on
 plugging changes in the block layer so needs to wait
 for those.
 It also contains a Kconfig fix for the new RAID10 support
 in dm-raid.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.18 (GNU/Linux)
 
 iQIVAwUAUBnKUznsnt1WYoG5AQJOQA/+M7RoVnF63+TbGIqdNDotuF8FxvudCZBl
 Ou2yG47EOPtWf/RoqPyfpydDgdjyXsk4T5TfXoc0hsXVr4shCYo51uT9K34TMSDJ
 2GzGWuyugRJFyvxW7PBgM+zFWlcVdgUGcwsdmIUMtHRz8Q10TqO5fE22RNLkhwOl
 fvGCK1KYnQqlG87DbulHWMo22vyZVic8jBqFSw55CPuuFMSJMxCw0rOPUnvk5Q8v
 jWzZzuUqrM8iiOxTDHsbCA0IleCbGl/m0tgk02Vj4tkCvz9N/xzQW2se0H6uECiK
 k8odbAiNBOh1q135sa7ASrBzxT+JqSiQ25rLheTEzzNxjFv6/NlntXmYu6HB+lD3
 DoHAvRjgMxiLCdisW6TJb10NItitXwE/HSpQOVRxyYtINdzmhIDaCccgfN8ZMkho
 nmE/uzO+CAoCFpZC2C/nY8D0BZs5fw4hgDAsci66mvs+88dy+SoA4AbyNEMAusOS
 tiL8ZEjnYXvxTh3JFaMIaqQd6PkbahmtEtvorwXsUYUdY0ybkcs2FYVksvkgYdyW
 WlejOZVurY2i5biqck3UqjesxeJA5TMAlAUQR7vXu1Fa9fYFXZbqJom/KnPRTfek
 xerCWPMbhuzmcyEjUOGfjs6GFEnEmRT6Q6fN3CBaQMS2Q/z+6AkTOXKVl5Fhvoyl
 aeu1m8nZLuI=
 =ovN2
 -----END PGP SIGNATURE-----

Merge tag 'md-3.6' of git://neil.brown.name/md

Pull additional md update from NeilBrown:
 "This contains a few patches that depend on plugging changes in the
  block layer so needed to wait for those.

  It also contains a Kconfig fix for the new RAID10 support in dm-raid."

* tag 'md-3.6' of git://neil.brown.name/md:
  md/dm-raid: DM_RAID should select MD_RAID10
  md/raid1: submit IO from originating thread instead of md thread.
  raid5: raid5d handle stripe in batch way
  raid5: make_request use batch stripe release
2012-08-02 11:34:40 -07:00
NeilBrown
d9f691c365 md/dm-raid: DM_RAID should select MD_RAID10
Now that DM_RAID supports raid10, it needs to select that code
to ensure it is included.

Cc: Jonathan Brassow <jbrassow@redhat.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2012-08-02 08:35:43 +10:00
Joe Thornber
3caf6d73d4 dm persistent data: remove debug space map checker
Remove debug space map checker from dm persistent data.

The space map checker is a wrapper for other space maps that double
checks the reference counts are correct.  It holds all these reference
counts in memory rather than on disk, so uses a lot of memory and is
thus restricted to small pools.

As yet, this checker hasn't found any issues, but has caused a few of
its own due to people turning it on by default with larger pools.

Removing.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27 15:07:58 +01:00
Mikulas Patocka
a4ffc15219 dm: add verity target
This device-mapper target creates a read-only device that transparently
validates the data on one underlying device against a pre-generated tree
of cryptographic checksums stored on a second device.

Two checksum device formats are supported: version 0 which is already
shipping in Chromium OS and version 1 which incorporates some
improvements.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Elly Jones <ellyjones@chromium.org>
Cc: Milan Broz <mbroz@redhat.com>
Cc: Olof Johansson <olofj@chromium.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28 18:43:38 +01:00
Alasdair G Kergon
035220b33d dm raid: no longer experimental
The dm raid module (using md) is becoming the preferred way of creating long-lived
mirrors through userspace LVM so remove the EXPERIMENTAL tag.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28 18:41:24 +01:00
Alasdair G Kergon
e0b215da8f dm uevent: no longer experimental
Drop EXPERIMENTAL tag from dm-uevent.

It's not changed for a while and some userspace tools are relying upon it.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28 18:41:24 +01:00
Joe Thornber
991d9fa02d dm: add thin provisioning target
Initial EXPERIMENTAL implementation of device-mapper thin provisioning
with snapshot support.  The 'thin' target is used to create instances of
the virtual devices that are hosted in the 'thin-pool' target.  The
thin-pool target provides data sharing among devices.  This sharing is
made possible using the persistent-data library in the previous patch.

The main highlight of this implementation, compared to the previous
implementation of snapshots, is that it allows many virtual devices to
be stored on the same data volume, simplifying administration and
allowing sharing of data between volumes (thus reducing disk usage).

Another big feature is support for arbitrary depth of recursive
snapshots (snapshots of snapshots of snapshots ...).  The previous
implementation of snapshots did this by chaining together lookup tables,
and so performance was O(depth).  This new implementation uses a single
data structure so we don't get this degradation with depth.

For further information and examples of how to use this, please read
Documentation/device-mapper/thin-provisioning.txt

Signed-off-by: Joe Thornber <thornber@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-10-31 20:21:18 +00:00
Mikulas Patocka
95d402f057 dm: add bufio
The dm-bufio interface allows you to do cached I/O on devices,
holding recently-read blocks in memory and performing delayed writes.

We don't use buffer cache or page cache already present in the kernel, because:
* we need to handle block sizes larger than a page
* we can't allocate memory to perform reads or we'd have deadlocks

Currently, when a cache is required, we limit its size to a fraction of
available memory.  Usage can be viewed and changed in
/sys/module/dm_bufio/parameters/ .

The first user is thin provisioning, but more dm users are planned.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-10-31 20:19:09 +00:00
Jonathan Brassow
b12d437b73 dm raid: support metadata devices
Add the ability to parse and use metadata devices to dm-raid.  Although
not strictly required, without the metadata devices, many features of
RAID are unavailable.  They are used to store a superblock and bitmap.

The role, or position in the array, of each device must be recorded in
its superblock.  This is to help with fault handling, array reshaping,
and sanity checks.  RAID 4/5/6 devices must be loaded in a specific order:
in this way, the 'array_position' field helps validate the correctness
of the mapping when it is loaded.  It can be used during reshaping to
identify which devices are added/removed.  Fault handling is impossible
without this field.  For example, when a device fails it is recorded in
the superblock.  If this is a RAID1 device and the offending device is
removed from the array, there must be a way during subsequent array
assembly to determine that the failed device was the one removed.  This
is done by correlating the 'array_position' field and the bit-field
variable 'failed_devices'.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-08-02 12:32:07 +01:00
Josef Bacik
3407ef5262 dm: add flakey target
This target is the same as the linear target except that it returns I/O
errors periodically.  It's been found useful in simulating failing
devices for testing purposes.

I needed a dm target to do some failure testing on btrfs's raid code, and
Mike pointed me at this.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-03-24 13:54:24 +00:00
NeilBrown
9d09e663d5 dm: raid456 basic support
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>
2011-01-13 20:00:02 +00:00
David Woodhouse
2144381da4 Merge branch 'async' of macbook:git/btrfs-unstable
Conflicts:
	drivers/md/Makefile
	lib/raid6/unroll.pl
2010-08-09 10:36:44 +01:00
NeilBrown
08fb730ca3 md: remove EXPERIMENTAL designation from RAID10
RAID10 has been available for quite a while now and is quite well
tested, so we can remove the EXPERIMENTAL designation.

Reported-by: Eric MSP Veith <eveith@wwweb-library.net>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:58 +10:00
NeilBrown
93bd89a6d5 md: revise Kconfig help for MD_MULTIPATH
Make it clear in the config message that MD_MULTIPATH is not under
active development.

Cc: Oren Held <orenhe@il.ibm.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2009-12-14 12:51:41 +11:00
David Woodhouse
e5d84970a5 async_tx: Move ASYNC_RAID6_TEST option to crypto/async_tx/, fix dependencies
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-10-29 16:41:49 +00:00
David Woodhouse
f5e70d0fe3 md: Factor out RAID6 algorithms into lib/
We'll want to use these in btrfs too.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-10-29 14:38:47 +00:00
Dan Williams
bbb20089a3 Merge branch 'dmaengine' into async-tx-next
Conflicts:
	crypto/async_tx/async_xor.c
	drivers/dma/ioat/dma_v2.h
	drivers/dma/ioat/pci.c
	drivers/md/raid5.c
2009-09-08 17:55:21 -07:00
Dan Williams
07a3b417dc md/raid456: distribute raid processing over multiple cores
Now that the resources to handle stripe_head operations are allocated
percpu it is possible for raid5d to distribute stripe handling over
multiple cores.  This conversion also adds a call to cond_resched() in
the non-multicore case to prevent one core from getting monopolized for
raid operations.

Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-08-29 19:13:13 -07:00
Dan Williams
ac6b53b6e6 md/raid6: asynchronous raid6 operations
[ Based on an original patch by Yuri Tikhonov ]

The raid_run_ops routine uses the asynchronous offload api and
the stripe_operations member of a stripe_head to carry out xor+pq+copy
operations asynchronously, outside the lock.

The operations performed by RAID-6 are the same as in the RAID-5 case
except for no support of STRIPE_OP_PREXOR operations. All the others
are supported:
STRIPE_OP_BIOFILL
 - copy data into request buffers to satisfy a read request
STRIPE_OP_COMPUTE_BLK
 - generate missing blocks (1 or 2) in the cache from the other blocks
STRIPE_OP_BIODRAIN
 - copy data out of request buffers to satisfy a write request
STRIPE_OP_RECONSTRUCT
 - recalculate parity for new data that has entered the cache
STRIPE_OP_CHECK
 - verify that the parity is correct

The flow is the same as in the RAID-5 case, and reuses some routines, namely:
1/ ops_complete_postxor (renamed to ops_complete_reconstruct)
2/ ops_complete_compute (updated to set up to 2 targets uptodate)
3/ ops_run_check (renamed to ops_run_check_p for xor parity checks)

[neilb@suse.de: fixes to get it to pass mdadm regression suite]
Reviewed-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-08-29 19:13:12 -07:00
Dan Williams
cb3c82992f async_tx: raid6 recovery self test
Port drivers/md/raid6test/test.c to use the async raid6 recovery
routines.  This is meant as a unit test for raid6 acceleration drivers.  In
addition to the 16-drive test case this implements tests for the 4-disk and
5-disk special cases (dma devices can not generically handle less than 2
sources), and adds a test for the D+Q case.

Reviewed-by: Andre Noll <maan@systemlinux.org>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-08-29 19:09:28 -07:00
Jonthan Brassow
f5db4af466 dm raid1: add userspace log
This patch contains a device-mapper mirror log module that forwards
requests to userspace for processing.

The structures used for communication between kernel and userspace are
located in include/linux/dm-log-userspace.h.  Due to the frequency,
diversity, and 2-way communication nature of the exchanges between
kernel and userspace, 'connector' was chosen as the interface for
communication.

The first log implementations written in userspace - "clustered-disk"
and "clustered-core" - support clustered shared storage.   A userspace
daemon (in the LVM2 source code repository) uses openAIS/corosync to
process requests in an ordered fashion with the rest of the nodes in the
cluster so as to prevent log state corruption.  Other implementations
with no association to LVM or openAIS/corosync, are certainly possible.

(Imagine if two machines are writing to the same region of a mirror.
They would both mark the region dirty, but you need a cluster-aware
entity that can handle properly marking the region clean when they are
done.  Otherwise, you might clear the region when the first machine is
done, not the second.)

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-06-22 10:12:35 +01:00
Kiyoshi Ueda
f392ba889b dm mpath: add service time load balancer
This patch adds a service time oriented dynamic load balancer,
dm-service-time, which selects the path with the shortest estimated
service time for the incoming I/O.
The service time is estimated by dividing the in-flight I/O size
by a performance value of each path.

The performance value can be given as a table argument at the table
loading time.  If no performance value is given, all paths are
considered equal.

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: Alasdair G Kergon <agk@redhat.com>
2009-06-22 10:12:28 +01:00
Kiyoshi Ueda
fd5e033908 dm mpath: add queue length load balancer
This patch adds a dynamic load balancer, dm-queue-length, which
balances the number of in-flight I/Os across the paths.

The code is based on the patch posted by Stefan Bader:
https://www.redhat.com/archives/dm-devel/2005-October/msg00050.html

Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
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: Alasdair G Kergon <agk@redhat.com>
2009-06-22 10:12:27 +01:00
NeilBrown
2cffc4a01d md: remove CONFIG_MD_RAID_RESHAPE config option.
This was only needed when the code was experimental.  Most of it
is well tested now, so the option is no longer useful.

Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 15:27:05 +11:00
Dan Williams
f701d589aa md/raid6: move raid6 data processing to raid6_pq.ko
Move the raid6 data processing routines into a standalone module
(raid6_pq) to prepare them to be called from async_tx wrappers and other
non-md drivers/modules.  This precludes a circular dependency of raid456
needing the async modules for data processing while those modules in
turn depend on raid456 for the base level synchronous raid6 routines.

To support this move:
1/ The exportable definitions in raid6.h move to include/linux/raid/pq.h
2/ The raid6_call, recovery calls, and table symbols are exported
3/ Extra #ifdef __KERNEL__ statements to enable the userspace raid6test to
   compile

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 15:09:39 +11:00
Alan Jenkins
ce52aebd02 raid, fastboot: hide RAID autodetect option if MD is compiled as a module
Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-12 08:25:14 -07:00
Arjan van de Ven
a364092a41 raid: make RAID autodetect default a KConfig option
RAID autodetect has the side effect of requiring synchronisation
of all device drivers, which can make the boot several seconds longer
(I've measured 7 on one of my laptops).... even for systems that don't
have RAID setup for the root filesystem (the only FS where this matters).

This patch makes the default for autodetect a config option; either way
the user can always override via the kernel command line.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: NeilBrown <neilb@suse.de>
2008-10-12 08:25:02 -07:00
Chandra Seetharaman
fe9233fb69 [SCSI] scsi_dh: fix kconfig related build errors
Do not automatically "select" SCSI_DH for dm-multipath. If SCSI_DH
doesn't exist,just do not allow  hardware handlers to be used.

Handle SCSI_DH being a module also. Make sure it doesn't allow DM_MULTIPATH
to be compiled in when SCSI_DH is a module.

[jejb: added comment for Kconfig syntax]
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-15 09:16:43 -05:00
Chandra Seetharaman
cb520223d7 [SCSI] scsi_dh: Remove hardware handlers from dm
This patch removes the 3 hardware handlers that currently exist
under dm as the functionality is moved to SCSI layer in the earlier
patches.

[jejb: removed more makefile hunks and rejection fixes]
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:41 -05:00
Chandra Seetharaman
cfae5c9bb6 [SCSI] scsi_dh: Use SCSI device handler in dm-multipath
This patch converts dm-mpath to use scsi device handlers instead of
dm's hardware handlers.

This patch does not add any new functionality. Old behaviors remain and
userspace tools work as is except that arguments supplied with hardware
handler are ignored.

One behavioral exception is: Activation of a path is synchronous in this
patch, opposed to the older behavior of being asynchronous (changed in
patch 07: scsi_dh: Add a single threaded workqueue for initializing a path)

Note: There is no need to get a reference for the device handler module
(as it was done in the dm hardware handler case) here as the reference
is held when the device was first found. Instead we check and make sure
that support for the specified device is present at table load time.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:41 -05:00
Alasdair G Kergon
0149e57fed dm: targets no longer experimental
Drop the EXPERIMENTAL tag from well-established device-mapper targets, so
the newer ones stand out better.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-02-08 02:10:32 +00:00
Paul Mundt
d1622e8909 dm mpath: hp requires scsi
With CONFIG_SCSI=n __scsi_print_sense() is never linked in.

drivers/built-in.o: In function `hp_sw_end_io':
dm-mpath-hp-sw.c:(.text+0x914f8): undefined reference to `__scsi_print_sense'

Caught with a randconfig on current git.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-12-20 17:32:09 +00:00
Mike Anderson
51e5b2bd34 dm: add uevent to core
This patch adds a uevent skeleton to device-mapper.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20 02:01:24 +01:00
Dave Wysochanski
16ebbf3584 dm mpath: add hp handler
This patch adds the most basic dm-multipath hardware support for the
HP active/passive arrays.

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20 02:01:19 +01:00
Randy Dunlap
6e106b0d97 DM_MULTIPATH_RDAC: "scsi_normalize_sense" undefined
DM_MULTIPATH_RDAC uses SCSI API(s) and is for a SCSI device,
so add SCSI to its depends on to prevent build errors.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
[ Tested and Verified by Chandra Seetharaman ]
Acked-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-24 16:10:39 -07:00
Jan Engelhardt
afd44034ac Use menuconfig objects II - MD
Change Kconfig objects from "menu, config" into "menuconfig" so
that the user can disable the whole feature without having to
enter the menu first.

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:15 -07:00