Adrian Hunter [Fri, 20 Mar 2009 10:09:04 +0000 (11:09 +0100)]
UBIFS: fix recovery bug
UBIFS did not recovery in a situation in which it could
have. The relevant function assumed there could not be
more nodes in an eraseblock after a corrupted node, but
in fact the last (NAND) page written might contain anything.
The correct approach is to check for empty space (0xFF bytes)
from then on.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Mark Brown [Mon, 16 Mar 2009 19:36:34 +0000 (19:36 +0000)]
regulator: Support disabling of unused regulators by machines
At present it is not possible for machine constraints to disable
regulators which have been left on when the system starts, for example
as a result of fixed default configurations in hardware. This means that
power may be wasted by these regulators if they are not in use.
Provide intial support for this with a late_initcall which will disable
any unused regulators if the machine has enabled this feature by calling
regulator_has_full_constraints(). If this has not been called then print
a warning to encourage users to fully specify their constraints so that
we can change this to be the default behaviour in future.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Mon, 16 Mar 2009 19:36:33 +0000 (19:36 +0000)]
regulator: Don't increment use_count for boot_on regulators
Don't set use_count for regulators that are enabled at boot since this
stops the supply being disabled by well-behaved consumers which do
balanced enables and disabled. Any consumers which don't do disables
which are not matched by enables are unable to share regulators - shared
regulators are the common case so the API should facilitate them.
Consumers that want to disable regulators that are enabled when they
start have two options:
- Do a regulator_enable() prior to the disable to bring the use count
in sync with the hardware state; this will ensure that if the
regulator was enabled by another driver then this consumer will play
nicely with it.
- Use regulator_force_disable(); this explicitly bypasses any checks
done by the core and documents the inability of the driver to share
the supply.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Sat, 14 Mar 2009 00:54:54 +0000 (17:54 -0700)]
twl4030-regulator: expose VPLL2
Add VPLL2 to the set of twl4030-family regulators exposed for
use by various drivers. It's commonly used to power the digital
video outputs (e.g. LCD or DVI displays) on OMAP3 systems.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Thu, 12 Mar 2009 00:43:34 +0000 (16:43 -0800)]
regulator: refcount fixes
Fix some refcounting issues in the regulator framework, supporting
regulator_disable() for regulators that were enabled at boot time
via machine constraints:
- Update those regulators' usecounts after enabling, so they
can cleanly be disabled at that level.
- Remove the problematic per-consumer usecount, so there's
only one level of enable/disable.
Buggy consumers could notice different bug symptoms. The main
example would be refcounting bugs; also, any (out-of-tree) users
of the experimental regulator_set_optimum_mode() stuff which
don't call it when they're done using a regulator.
This is a net minor codeshrink.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Wed, 11 Mar 2009 23:35:52 +0000 (23:35 +0000)]
regulator: Don't warn if we failed to get a regulator
The consumer can print a message if required, some consumers may have
optional regulators and wish to downgrade the logging for them or ignore
their absence.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Mon, 2 Mar 2009 16:32:46 +0000 (16:32 +0000)]
regulator: Allow boot_on regulators to be disabled by clients
Rather than incrementing the reference count for boot_on regulators
(which prevents them being disabled later on) simply force the
regulator to be enabled when applying the constraints. Previously
boot_on was essentially equivalent to always_on.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Mon, 2 Mar 2009 16:32:47 +0000 (16:32 +0000)]
regulator: Implement list_voltage for WM835x LDOs and DCDCs
Implement the recently added voltage step listing API for the WM835x
DCDCs and LDOs. DCDCs can use values up to 0x66, LDOs can use the full
range of values in the mask. Both masks are the lower bits of the
register.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Tue, 10 Mar 2009 19:51:15 +0000 (11:51 -0800)]
twl4030-regulator: list more VAUX4 voltages
The VAUX4 voltage table scrolls onto a second page in many versions
of the TWL4030 family manuals. This doesn't mean we should ignore
those values! Some boards use the (fully supported) 2.8V setting.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Tue, 10 Mar 2009 16:28:36 +0000 (16:28 +0000)]
regulator: Don't warn on omitted voltage constraints
Specifying voltage constraints is optional (and only needed if the
consumer is allowed to change the voltage) so don't complain unless
a voltage has been specified.
Also avoid surprises with a dangling else while we're here.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Wed, 11 Mar 2009 11:30:43 +0000 (03:30 -0800)]
MMC: regulator utilities
Glue between MMC and regulator stacks ... verified with
some OMAP3 boards using adjustable and configured-as-fixed
regulators on several MMC controllers.
These calls are intended to be used by MMC host adapters
using at least one regulator per host. Examples include
slots with regulators supporting multiple voltages and
ones using multiple voltage rails (e.g. DAT4..DAT7 using a
separate supply, or a split rail chip like certain SDIO
WLAN or eMMC solutions).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Pierre Ossman <drzeus@drzeus.cx> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Thu, 26 Feb 2009 19:50:14 +0000 (11:50 -0800)]
regulator: twl4030 voltage enumeration (v2)
Update previously-posted twl4030 regulator driver to export
supported voltages to upper layers using a new mechanism.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Sun, 8 Feb 2009 18:37:06 +0000 (10:37 -0800)]
regulator: twl4030 regulators
Support most of the LDO regulators in the twl4030 family chips.
In the case of LDOs supporting MMC/SD, the voltage controls are
used; but in most other cases, the regulator framework is only
used to enable/disable a supplies, conserving power when a given
voltage rail is not needed.
The drivers/mfd/twl4030-core.c code already sets up the various
regulators according to board-specific configuration, and knows
that some chips don't provide the full set of voltage rails.
The omitted regulators are intended to be under hardware control,
such as during the hardware-mediated system powerup, powerdown,
and suspend states. Unless/until software hooks are known to
be safe, they won't be exported here.
These regulators implement the new get_status() operation, but
can't realistically implement get_mode(); the status output is
effectively the result of a vote, with the relevant hardware
inputs not exposed.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Thu, 26 Feb 2009 21:28:41 +0000 (13:28 -0800)]
regulator: get_status() grows kerneldoc
Add kerneldoc for the new get_status() message. Fix the existing
kerneldoc for that struct in two ways:
(a) Syntax, making sure parameter descriptions immediately
follow the one-line struct description and that the first
blank lines is before any more expansive description;
(b) Presentation for a few points, to highlight the fact that
the previous "get" methods exist only to report the current
configuration, not to display actual status.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Thu, 26 Feb 2009 19:48:36 +0000 (11:48 -0800)]
regulator: enumerate voltages (v2)
Add a basic mechanism for regulators to report the discrete
voltages they support: list_voltage() enumerates them using
selectors numbered from 0 to an upper bound.
Use those methods to force machine-level constraints into bounds.
(Example: regulator supports 1.8V, 2.4V, 2.6V, 3.3V, and board
constraints for that rail are 2.0V to 3.6V ... so the range of
voltages is then 2.4V to 3.3V on this board.)
Export those voltages to the regulator consumer interface, so for
example regulator hooked up to an MMC/SD/SDIO slot can report the
actual voltage options available to cards connected there.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Wed, 11 Feb 2009 15:32:06 +0000 (15:32 +0000)]
regulator: Suggest use of datasheet supply or pin names for consumers
Update the documentation to suggest the use of datasheet names for
the supplies requested by regulator consumers. Doing this makes it
easier to tie the design for a given platform up with the requirements
of the driver for a consumer.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mike Rapoport [Thu, 22 Jan 2009 14:00:29 +0000 (16:00 +0200)]
regulator: add unset_regulator_supplies to fix regulator_unregister
Currently regulator_unregister does not clear regulator <--> consumer
mapping.
This patch introduces unset_regulator_supplies that clear the map.
Signed-off-by: Mike Rapoport <mike@compulab.co.il> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Wed, 21 Jan 2009 14:08:40 +0000 (14:08 +0000)]
regulator: Hoist struct regulator_dev out of core to fix notifiers
Commit 872ed3fe176833f7d43748eb88010da4bbd2f983 caused regulator drivers
to take the struct regulator_dev lock themselves which requires that the
struct be visible to them. Band aid this by making the struct visible.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Mon, 19 Jan 2009 13:37:05 +0000 (13:37 +0000)]
regulator: Make fixed voltage regulators visible in Kconfig
This allows users to enable or disable support for these regulators at
build time as they can for other regulators rather than having platforms
force the regulators to be built in.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Mark Brown [Mon, 19 Jan 2009 13:37:02 +0000 (13:37 +0000)]
regulator: Pass regulator init data as explict argument when registering
Rather than having the regulator init data read from the platform_data
member of the struct device that is registered for the regulator make
the init data an explict argument passed in when registering. This
allows drivers to use the platform data for their own purposes if they
wish.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Jonathan Cameron [Mon, 19 Jan 2009 18:20:58 +0000 (18:20 +0000)]
Regulator: Push lock out of _notifier_call_chain + add voltage change event.
Regulator: Push lock out of _notifier_call_chain and into caller functions
(side effect of fixing deadlock in regulator_force_disable)
+ Add a voltage changed event. Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Thu, 15 Jan 2009 07:03:17 +0000 (23:03 -0800)]
regulator: add get_status()
Based on previous LKML discussions:
* Update docs for regulator sysfs class attributes to highlight
the fact that all current attributes are intended to be control
inputs, including notably "state" and "opmode" which previously
implied otherwise.
* Define a new regulator driver get_status() method, which is the
first method reporting regulator outputs instead of inputs.
It can report on/off and error status; or instead of simply
"on", report the actual operating mode.
For the moment, this is a sysfs-only interface, not accessible to
regulator clients. Such clients can use the current notification
interfaces to detect errors, if the regulator reports them.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell [Wed, 14 Jan 2009 21:16:27 +0000 (13:16 -0800)]
regulator: minor cleanup of virtual consumer
Minor cleanup to the regulator set_mode sysfs support:
switch to sysfs_streq() in set_mode(), which is also
a code shrink. Use the same strings that get_mode()
uses, shrinking data too.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
NeilBrown [Tue, 31 Mar 2009 04:28:40 +0000 (15:28 +1100)]
md/raid5 revise rules for when to update metadata during reshape
We currently update the metadata :
1/ every 3Megabytes
2/ When the place we will write new-layout data to is recorded in
the metadata as still containing old-layout data.
Rule one exists to avoid having to re-do too much reshaping in the
face of a crash/restart. So it should really be time based rather
than size based. So change it to "every 10 seconds".
Rule two turns out to be too harsh when restriping an array
'in-place', as in that case the metadata much be updates for every
stripe.
For the in-place update, it can only possibly be safe from a crash if
some user-space program data a backup of every e.g. few hundred
stripes before allowing them to be reshaped. In that case, the
constant metadata update is pointless.
So only update the metadata if the new metadata will report that the
end of the 'old-layout' data is beyond where we are currently
writing 'new-layout' data.
NeilBrown [Tue, 31 Mar 2009 04:26:47 +0000 (15:26 +1100)]
md/raid5: be more careful about write ordering when reshaping.
When we are reshaping an array, it is very important that we read
the data from a particular sector offset before writing new data
at that offset.
In most cases when growing or shrinking an array we read long before
we even consider writing. But when restriping an array without
changing it size, there is a small possibility that we might have
some data to available write before the read has happened at the same
location. This would require some stripes to be in cache already.
To guard against this small possibility, we check, before writing,
that the 'old' stripe at the same location is not in the process of
being read. And we ensure that we mark all 'source' stripes as such
before allowing new 'destination' stripes to proceed.
NeilBrown [Tue, 31 Mar 2009 04:19:07 +0000 (15:19 +1100)]
md/raid5: prepare for allowing reshape to change chunksize.
Add "prev_chunk" to raid5_conf_t, similar to "previous_raid_disks", to
remember what the chunk size was before the reshape that is currently
underway.
This seems like duplication with "chunk_size" and "new_chunk" in
mddev_t, and to some extent it is, but there are differences.
The values in mddev_t are always defined and often the same.
The prev* values are only defined if a reshape is underway.
Also (and more significantly) the raid5_conf_t values will be changed
at the same time (inside an appropriate lock) that the reshape is
started by setting reshape_position. In contrast, the new_chunk value
is set when the sysfs file is written which could be well before the
reshape starts.
NeilBrown [Tue, 31 Mar 2009 04:19:03 +0000 (15:19 +1100)]
md/raid5: clearly differentiate 'before' and 'after' stripes during reshape.
During a raid5 reshape, we have some stripes in the cache that are
'before' the reshape (and are still to be processed) and some that are
'after'. They are currently differentiated by having different
->disks values as the only reshape current supported involves changing
the number of disks.
However we will soon support reshapes that do not change the number
of disks (chunk parity or chunk size). So make the difference more
explicit with a 'generation' number.
NeilBrown [Tue, 31 Mar 2009 04:17:38 +0000 (15:17 +1100)]
md: allow number of drives in raid5 to be reduced
When reshaping a raid5 to have fewer devices, we work from the end of
the array to the beginning.
md_do_sync gives addresses to sync_request that go from the beginning
to the end. So largely ignore them use the internal state variable
"reshape_progress" to keep track of what to do next.
Never allow the size to be reduced below the minimum (4 for raid6,
3 otherwise).
We require that the size of the array has already been reduced before
the array is reshaped to a smaller size. This is because simply
reducing the size is an easily reversible operation, while the reshape
is immediately destructive and so is not reversible for the blocks at
the ends of the devices.
Thus to reshape an array to have fewer devices, you must first write
an appropriately small size to md/array_size.
When reshape finished, we remove any drives that are no longer
needed and fix up ->degraded.
NeilBrown [Tue, 31 Mar 2009 04:16:46 +0000 (15:16 +1100)]
md/raid5: change reshape-progress measurement to cope with reshaping backwards.
When reducing the number of devices in a raid4/5/6, the reshape
process has to start at the end of the array and work down to the
beginning. So we need to handle expand_progress and expand_lo
differently.
This patch renames "expand_progress" and "expand_lo" to avoid the
implication that anything is getting bigger (expand->reshape) and
every place they are used, we make sure that they are used the right
way depending on whether delta_disks is positive or negative.
NeilBrown [Tue, 31 Mar 2009 04:15:05 +0000 (15:15 +1100)]
md: add explicit method to signal the end of a reshape.
Currently raid5 (the only module that supports restriping)
notices that the reshape has finished be sync_request being
given a large value, and handles any cleanup them.
This patch changes it so md_check_recovery calls into an
explicit finish_reshape method as well.
The clean-up from sync_request can do things that need to be
done promptly, typically things local to the raid5_conf_t
structure.
The "finish_reshape" method is called under the mddev_lock
so it can do things involving reconfiguring the device.
This allows us to get rid of md_set_array_sectors_locked, which
would have caused a deadlock if you tried to stop and array
while a reshape was happening.
NeilBrown [Tue, 31 Mar 2009 04:10:36 +0000 (15:10 +1100)]
md/raid5: enhance raid5_size to work correctly with negative delta_disks
This is the first of four patches which combine to allow md/raid5 to
reduce the number of devices in the array by restriping the data over
a subset of the devices.
If the number of disks in a raid4/5/6 is being reduced, then the
default size must be based on the new number, not the old number
of devices.
In general, it should be based on the smaller of new and old.
Dan Williams [Tue, 31 Mar 2009 04:09:39 +0000 (15:09 +1100)]
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>
Dan Williams [Tue, 31 Mar 2009 04:00:31 +0000 (15:00 +1100)]
md: 'array_size' sysfs attribute
Allow userspace to set the size of the array according to the following
semantics:
1/ size must be <= to the size returned by mddev->pers->size(mddev, 0, 0)
a) If size is set before the array is running, do_md_run will fail
if size is greater than the default size
b) A reshape attempt that reduces the default size to less than the set
array size should be blocked
2/ once userspace sets the size the kernel will not change it
3/ writing 'default' to this attribute returns control of the size to the
kernel and reverts to the size reported by the personality
Also, convert locations that need to know the default size from directly
reading ->array_sectors to <pers>_size. Resync/reshape operations
always follow the default size.
Finally, fixup other locations that read a number of 1k-blocks from
userspace to use strict_blocks_to_sectors() which checks for unsigned
long long to sector_t overflow and blocks to sectors overflow.
Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams [Tue, 31 Mar 2009 03:59:03 +0000 (14:59 +1100)]
md: centralize ->array_sectors modifications
Get personalities out of the business of directly modifying
->array_sectors. Lays groundwork to introduce policy on when
->array_sectors can be modified.
Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams [Wed, 18 Mar 2009 01:10:40 +0000 (18:10 -0700)]
md: add 'size' as a personality method
In preparation for giving userspace control over ->array_sectors we need
to be able to retrieve the 'default' size, and the 'anticipated' size
when a reshape is requested. For personalities that do not reshape emit
a warning if anything but the default size is requested.
In the raid5 case we need to update ->previous_raid_disks to make the
new 'default' size available.
Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
NeilBrown [Tue, 31 Mar 2009 03:56:41 +0000 (14:56 +1100)]
md/raid5: allow layout/chunksize to be changed on an active 2-drive raid5.
2-drive raid5's aren't very interesting. But if you are converting
a raid1 into a raid5, you will at least temporarily have one. And
that it a good time to set the layout/chunksize for the new RAID5
if you aren't happy with the defaults.
layout and chunksize don't actually affect the placement of data
on a 2-drive raid5, so we just do some internal book-keeping.
NeilBrown [Tue, 31 Mar 2009 03:39:39 +0000 (14:39 +1100)]
md: add ->takeover method to support changing the personality managing an array
Implement this for RAID6 to be able to 'takeover' a RAID5 array. The
new RAID6 will use a layout which places Q on the last device, and
that device will be missing.
If there are any available spares, one will immediately have Q
recovered onto it.
NeilBrown [Tue, 31 Mar 2009 03:39:39 +0000 (14:39 +1100)]
md: enable suspend/resume of md devices.
To be able to change the 'level' of an md/raid array, we need to
suspend the device so that no requests are active - then move some
pointers around etc.
The code already keeps counts of active requests and the ->quiesce
function can be used to wait until those counts hit zero.
However the quiesce function blocks new requests once they are all
ready 'inside' the personality module, and that is too late if we want
to replace the personality modules.
So make all md requests come in through a common md_make_request
function that keeps track of how many requests have entered the
modules but may not yet be on the internal reference counts.
Allow md_make_request to be blocked when we want to suspend the
device, and make it possible to wait for all those in-transit requests
to be added to internal lists so that ->quiesce can wait for them.
There is still a problem that when a request completes, we drop the
ref count inside the personality code so there is a short time between
when the refcount hits zero, and when the personality code is no
longer being used.
The personality code never blocks (schedule or spinlock) between
dropping the refcount and exiting the routine, so this should be safe
(as put_module calls synchronize_sched() before unmapping the module
code).
NeilBrown [Tue, 31 Mar 2009 03:39:39 +0000 (14:39 +1100)]
md: md_unregister_thread should cope with being passed NULL
Mostly md_unregister_thread is only called when we know that the
thread is NULL, but sometimes we need to check first. It is safer
to put the check inside md_unregister_thread itself.
NeilBrown [Tue, 31 Mar 2009 03:39:38 +0000 (14:39 +1100)]
md: make sure new_level, new_chunksize, new_layout always have sensible values.
When an md array is undergoing a change, we have new_* fields that
show the new values.
When no change is happening, it is least confusing if these have
the same value as the normal fields.
This is true in most cases, but not when the values are set via sysfs.
So fix this up.
A subsequent patch will BUG_ON if these things aren't consistent.
NeilBrown [Tue, 31 Mar 2009 03:39:38 +0000 (14:39 +1100)]
md/raid5: finish support for DDF/raid6
DDF requires RAID6 calculations over different devices in a different
order.
For md/raid6, we calculate over just the data devices, starting
immediately after the 'Q' block.
For ddf/raid6 we calculate over all devices, using zeros in place of
the P and Q blocks.
NeilBrown [Tue, 31 Mar 2009 03:39:38 +0000 (14:39 +1100)]
md/raid5: Add support for new layouts for raid5 and raid6.
DDF uses different layouts for P and Q blocks than current md/raid6
so add those that are missing.
Also add support for RAID6 layouts that are identical to various
raid5 layouts with the simple addition of one device to hold all of
the 'Q' blocks.
Finally add 'raid5' layouts to match raid4.
These last to will allow online level conversion.
Note that this does not provide correct support for DDF/raid6 yet
as the order in which data blocks are summed to produce the Q block
is significant and different between current md code and DDF
requirements.
NeilBrown [Tue, 31 Mar 2009 03:39:38 +0000 (14:39 +1100)]
md/raid6: remove expectation that Q device is immediately after P device.
Code currently assumes that the devices in a raid6 stripe are
0 1 ... N-1 P Q
in some rotated order. We will shortly add new layouts in which
this strict pattern is broken.
So remove this expectation. We still assume that the data disks
are roughly in-order. However P and Q can be inserted anywhere within
that order.
NeilBrown [Tue, 31 Mar 2009 03:39:38 +0000 (14:39 +1100)]
md/raid5: simplify interface for init_stripe and get_active_stripe
Rather than passing 'pd_idx' and 'disks' to these functions, just pass
'previous' which tells whether to use the 'previous' or 'current'
geometry during a reshape, and let init_stripe calculate
disks and pd_idx and anything else it might need.
This is not a substantial simplification and even adds a division.
However we will shortly be adding more complexity to init_stripe
to handle more interesting 'reshape' activities, and without this
change, the interface to these functions would get very complex.
Andre Noll [Tue, 31 Mar 2009 03:33:13 +0000 (14:33 +1100)]
md: Make mddev->size sector-based.
This patch renames the "size" field of struct mddev_s to "dev_sectors"
and stores the number of 512-byte sectors instead of the number of
1K-blocks in it.
All users of that field, including raid levels 1,4-6,10, are adjusted
accordingly. This simplifies the code a bit because it allows to get
rid of a couple of divisions/multiplications by two.
In order to make checkpatch happy, some minor coding style issues
have also been addressed. In particular, size_store() now uses
strict_strtoull() instead of simple_strtoull().
Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
NeilBrown [Tue, 31 Mar 2009 03:33:13 +0000 (14:33 +1100)]
md: be more consistent about setting WriteMostly flag when adding a drive to an array
When a drive is added to an array using ADD_NEW_DISK, there are two
places we can get certain flags from: the metadata on the disk or the
flags passed through the IOCTL.
For the WriteMostly flag (aka MD_DISK_WRITEMOSTLY) we take the value
from either of those sources depending on if it is set (i.e. we
effectively 'or' the two sources together).
This makes it awkward to clear, and is at best inconsistent.
As documented code (in mdadm) requires that setting
MD_DISK_WRITEMOSTLY in the ioctl will be effective, we resolve the
inconsistency by always using the value for this flag from the ioctl,
and ignoring the value on disk.
NeilBrown [Tue, 31 Mar 2009 03:33:13 +0000 (14:33 +1100)]
md: occasionally checkpoint drive recovery to reduce duplicate effort after a crash
Version 1.x metadata has the ability to record the status of a
partially completed drive recovery.
However we only update that record on a clean shutdown.
It would be nice to update it on unclean shutdowns too, particularly
when using a bitmap that removes much to the 'sync' effort after an
unclean shutdown.
One complication with checkpointing recovery is that we only know
where we are up to in terms of IO requests started, not which ones
have completed. And we need to know what has completed to record
how much is recovered. So occasionally pause the recovery until all
submitted requests are completed, then update the record of where
we are up to.
When we have a bitmap, we already do that pause occasionally to keep
the bitmap up-to-date. So enhance that code to record the recovery
offset and schedule a superblock update.
And when there is no bitmap, just pause 16 times during the resync to
do a checkpoint.
'16' is a fairly arbitrary number. But we don't really have any good
way to judge how often is acceptable, and it seems like a reasonable
number for now.
Move the headers with the local structures for the disciplines and
bitmap.h into drivers/md/ so that they are more easily grepable for
hacking and not far away. md.h is left where it is for now as there
are some uses from the outside.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: NeilBrown <neilb@suse.de>
Use the -y variables instead of the old -objs so we can easily add
conditional objects to the modules. Also always use += to add
subobjects to avoid problems when placing additional objects in
some place in the file.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: NeilBrown <neilb@suse.de>
NeilBrown [Tue, 31 Mar 2009 03:27:02 +0000 (14:27 +1100)]
md: write bitmap information to devices that are undergoing recovery.
When we add some spares to an array and start recovery, and we have
a bitmap which is stored 'internally' on all devices, we call
bitmap_write_all to make sure the bitmap is correct on the new
device(s).
However that doesn't work as write_sb_page only writes to
'In_sync' devices, and devices undergoing recovery are not
'In_sync' until recovery finishes.
So extend write_sb_page (actually next_active_rdev) to include devices
that are under recovery.
NeilBrown [Tue, 31 Mar 2009 03:27:02 +0000 (14:27 +1100)]
md: never clear bit from the write-intent bitmap when the array is degraded.
It is safe to clear a bit from the write-intent bitmap for a raid1
if we know the data has been written to all devices, which is
what the current test does.
But it is not always safe to update the 'events_cleared' counter in
that case. This is because one request could complete successfully
after some other request has partially failed.
So simply disable the clearing and updating of events_cleared whenever
the array is degraded. This might end up not clearing some bits that
could safely be cleared, but it is safest approach.
Note that the bug fixed here did not risk corrupting data by letting
the array get out-of-sync. Rather it meant that when a device is
removed and re-added to the array, it might incorrectly require a full
recovery rather than just recovering based on the bitmap.
NeilBrown [Tue, 31 Mar 2009 03:27:02 +0000 (14:27 +1100)]
md: Allow write-intent bitmaps to have chunksize < PAGE_SIZE
md currently insists that the chunk size used for write-intent
bitmaps (the amount of data that corresponds to one chunk)
be at least one page.
The reason for this restriction is lost in the mists of time,
but a review of the code (and a vague memory) suggests that the only
problem would be related to resync. Resync tries very hard to
work in multiples of a page, but also needs to sync with units
of a bitmap_chunk too.
This connection comes out in the bitmap_start_sync call.
So change bitmap_start_sync to always work in multiples of a page.
If the bitmap chunk size is less that one page, we flag multiple
chunks as 'syncing' and generally make them all appear to the
resync routines like one chunk.
All other code either already works with data ranges that could
span multiple chunks, or explicitly only cares about a single chunk.
NeilBrown [Tue, 31 Mar 2009 03:27:02 +0000 (14:27 +1100)]
md: Fix is_mddev_idle test (again).
There are two problems with is_mddev_idle.
1/ sync_io is 'atomic_t' and hence 'int'. curr_events and all the
rest are 'long'.
So if sync_io were to wrap on a 64bit host, the value of
curr_events would go very negative suddenly, and take a very
long time to return to positive.
So do all calculations as 'int'. That gives us plenty of precision
for what we need.
2/ To initialise rdev->last_events we simply call is_mddev_idle, on
the assumption that it will make sure that last_events is in a
suitable range. It used to do this, but now it does not.
So now we need to be more explicit about initialisation.
Helge Deller [Tue, 6 Jan 2009 13:23:13 +0000 (14:23 +0100)]
parisc: blink all or loadavg LEDs on oops
- depending on machine type, blink all leds or just the loadavg
leds twice a second on oops.
- cancel_rearming_delayed_workqueue() is obsolete,
use cancel_delayed_work_sync() instead
Helge Deller [Sun, 8 Feb 2009 23:43:36 +0000 (00:43 +0100)]
parisc: add ftrace (function and graph tracer) functionality
This patch adds the ftrace debugging functionality to the parisc kernel.
It will currently only work with 64bit kernels, because the gcc options -pg
and -ffunction-sections can't be enabled at the same time and -ffunction-sections
is still needed to be able to link 32bit kernels.
Helge Deller [Fri, 13 Feb 2009 22:58:29 +0000 (23:58 +0100)]
parisc: simplify sys_clone()
No need to test clone_flags here and set parent_tidptr and child_tidptr
accordingly. The same check will be done in do_fork() and copy_process() anyway.