Commit Graph

24852 Commits

Author SHA1 Message Date
Jens Axboe
e2d74ac066 [PATCH] [BLOCK] cfq-iosched: change cfq io context linking from list to tree
On setups with many disks, we spend a considerable amount of time
looking up the process-disk mapping on each queue of io. Testing with
a NULL based block driver, this costs 40-50% reduction in throughput
for 1000 disks.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-28 08:59:01 +02:00
Paul Mackerras
cf66c897d7 Merge branch '85xx' of git://git.kernel.org/pub/scm/linux/kernel/git/galak/powerpc 2006-03-28 17:03:19 +11:00
Paul Mackerras
facee873de Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/galak/powerpc 2006-03-28 17:02:14 +11:00
Kumar Gala
78af90629c powerpc: remove OCP references
OCP isn't used in arch/powerpc and hopefully will never be.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2006-03-27 23:48:37 -06:00
Stephen Rothwell
b239cbe957 [PATCH] powerpc: make ISA floppies work again
We used to assume that a DMA mapping request with a NULL dev was for
ISA DMA.  This assumption was broken at some point.  Now we explicitly
pass the detected ISA PCI device in the floppy setup.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:36 +11:00
Anton Blanchard
69ed332498 [PATCH] powerpc: Fix some initcall return values
Non zero initcalls (except for -ENODEV) have started warning at boot.
Fix smt_setup and init_ras_IRQ.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:34 +11:00
Mike Kravetz
9fe901d124 [PATCH] powerpc: Workaround for pSeries RTAS bug
A bug in the RTAS services incorrectly interprets some bits in the CR
when called from the OS.  Specifically, bits in CR4.  The result could
be a firmware crash that also takes down the partition.  A firmware
fix is in the works.  We have seen this situation when performing DLPAR
operations.  As a temporary workaround, clear the CR in enter_rtas().
Note that enter_rtas() will not set any bits in CR4 before calling RTAS.

Also note that the 32 bit version of enter_rtas() should have the same
work around even though the chances of hitting the bug are much smaller
due to the lack of DLPAR on 32 bit kernels.  However, my assembly skills
are a bit rusty and the 32 bit code doesn't seem to follow the conventions
for where things should be saved.  In addition, I don't have a system
to test 32 bit kernels.  Help creating and at least touch testing the
same workaround for 32 bit would be appreciated.

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:33 +11:00
Arnd Bergmann
e78b47a590 [PATCH] spufs: fix __init/__exit annotations
spufs_init and spufs_exit should be marked correctly so
they can be removed when not needed.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:30 +11:00
Arnd Bergmann
f4d1749e95 [PATCH] powerpc: add hvc backend for rtas
Current Cell hardware is using the console through a set
of rtas calls. This driver is needed to get console
output on those boards.

Signed-off-by: Arnd Bergmann <abergman@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:28 +11:00
Ryan S. Arnold
45d607ed92 [PATCH] powerpc: hvc_console updates
These are some updates from both Ryan and Arnd for the hvc_console
driver:

The main point is to enable the inclusion of a console driver
for rtas, which is currrently needed for the cell platform.

Also shuffle around some data-type declarations and moves some
functions out of include/asm-ppc64/hvconsole.h and into a new
drivers/char/hvc_console.h file.

Signed-off-by: "Ryan S. Arnold" <rsa@us.ibm.com>
Signed-off-by: Arnd Bergmann <abergman@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:26 +11:00
Laurent MEYER
11089f08d9 [PATCH] powerpc: fix incorrect SA_ONSTACK behaviour for 64-bit processes
*) When setting a sighandler using sigaction() call, if the flag
SA_ONSTACK is set and no alternate stack is provided via sigaltstack(),
the kernel still try to install the alternate stack. This behavior is
the opposite of the one which is documented in Single Unix
Specifications V3.

*) Also when setting an alternate stack using sigaltstack() with the
flag SS_DISABLE, the kernel try to install the alternate stack on
signal delivery.

These two use cases makes the process crash at signal delivery.

This fixes it.

Signed-off-by: Laurent Meyer <meyerlau@fr.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:24 +11:00
Michael Ellerman
5149fa47ec [PATCH] powerpc: Cope with duplicate node & property names in /proc/device-tree
Various dodgy firmware might give us nodes and/or properties in the device
tree with conflicting names. That's generally ok, except for when we export
the device tree via /proc, so check when we're creating the proc device tree
and munge names accordingly.

Tested on a faked device tree with kexec, would be good if someone with
actual bogus firmware could try it, but just for completeness.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:23 +11:00
Michael Ellerman
d0160bf0b3 [PATCH] powerpc: Rename and export ppc64_firmware_features
We need to export ppc64_firmware_features for modules. Before we do that
I think we should probably rename it to powerpc_firmware_features.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:45:20 +11:00
Kumar Gala
9cf8ca3871 powerpc: Make uImage default build output for MPC8540 ADS
When we build for the MPC8540 ADS produce a uImage by default.
Updated the defconfig to reflect this as well.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2006-03-27 23:44:37 -06:00
Kumar Gala
5cd272085b powerpc: move math-emu over to arch/powerpc
Towards the goal of having arch/powerpc not build anything over in arch/ppc
move math-emu over.  Also, killed some references to arch/ppc/ in the
arch/powerpc Makefile which should belong in drivers/ when the particular
sub-arch's move over to arch/powerpc.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2006-03-27 23:43:27 -06:00
Anton Blanchard
2f25194dbe [PATCH] powerpc: export validate_sp for oprofile calltrace
Export validate_sp so we can use it in the oprofile calltrace code.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:19:52 +11:00
Anton Blanchard
72533db012 [PATCH] powerpc: Remove some ifdefs in oprofile_impl.h
- No one uses op_counter_config.valid, so remove it
- No need to ifdef around function protypes.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 16:19:49 +11:00
Kumar Gala
10d713aef2 powerpc: use memparse() for mem= command line parsing
Use memparse() instead of our own code for handling the parsing of mem=

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2006-03-27 18:26:42 -06:00
Kumar Gala
cbd312b94e ppc: fix strncasecmp prototype
Match, Linus's fix to arch/powerpc in arch/ppc. strcasecmp takes a size_t,
not an int, as its third argument.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2006-03-27 18:26:18 -06:00
Paul Mackerras
0a26b1364f ppc: Remove CHRP, POWER3 and POWER4 support from arch/ppc
32-bit CHRP machines are now supported only in arch/powerpc, as are
all 64-bit PowerPC processors.  This means that we don't use
Open Firmware on any platform in arch/ppc any more.

This makes PReP support a single-platform option like every other
platform support option in arch/ppc now, thus CONFIG_PPC_MULTIPLATFORM
is gone from arch/ppc.  CONFIG_PPC_PREP is the option that selects
PReP support and is generally what has replaced
CONFIG_PPC_MULTIPLATFORM within arch/ppc.

_machine is all but dead now, being #defined to 0.

Updated Makefiles, comments and Kconfig options generally to reflect
these changes.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 10:22:10 +11:00
Paul Mackerras
ff2e6d7e27 powerpc: Fix goof in 6xx and POWER4 idle power-save functions
This fixes a mistake I made when editing these functions - when I
took out the interrupt disabling code (because interrupts are now
disabled by the caller) I left the register that is used for the MSR
value to be used during doze/nap uninitialized.  This fixes it.

Also updated some of the comments in idle_power4.S and removed some
code that was copied over from idle_6xx.S but is no longer relevant
(we don't ever clear the CPU_FTR_CAN_NAP bit at runtime for POWER4).

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 09:28:14 +11:00
hawkes@sgi.com
e6ef0fca2c [IA64-SGI] sn_hwperf use of num_online_cpus()
Eliminate an unnecessary -- and flawed -- use of the expensive
num_online_cpus().

Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-27 13:47:44 -08:00
Andrew Morton
64840e2722 [CPUFREQ] powernow: remove private for_each_cpu_mask()
It is unneeded and wrong.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2006-03-27 15:06:08 -05:00
shin, jacob
eef5167e50 [CPUFREQ] hotplug cpu fix for powernow-k8
Andi's previous fix to initialise powernow_data on all siblings
will not work properly with CPU Hotplug.

Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2006-03-27 15:01:28 -05:00
Dave Jones
0bb065f29b Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/cpufreq-2.6 2006-03-27 14:56:39 -05:00
David Woodhouse
2638fed7cc [PATCH] softmac: reduce default rate to 11Mbps.
We don't make much of an attempt to fall back to lower rates, and 54M
just isn't reliable enough for many people. In fact, it's not clear we
even set it to 11M if we're trying to associate with an 802.11b AP.

This patch makes us default to 11M, which ought to work for most people.
When we actually handle dynamic rate adjustment, we can reconsider the
defaults -- but even then, probably it makes as much sense to start at
11M and adjust it upwards as it does to start at 54M and reduce it.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2006-03-27 14:04:13 -05:00
David Woodhouse
16f4352733 [PATCH] softmac: reduce scan dwell time
It currently takes something like 8 seconds to do a scan, because we
spend half a second on each channel. Reduce that time to 20ms per
channel.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2006-03-27 14:04:09 -05:00
Chen, Kenneth W
ce9eed5a98 [IA64] optimize flush_tlb_range on large numa box
It was reported from a field customer that global spin lock ptcg_lock
is giving a lot of grief on munmap performance running on a large numa
machine.  What appears to be a problem coming from flush_tlb_range(),
which currently unconditionally calls platform_global_tlb_purge().
For some of the numa machines in existence today, this function is
mapped into ia64_global_tlb_purge(), which holds ptcg_lock spin lock
while executing ptc.ga instruction.

Here is a patch that attempt to avoid global tlb purge whenever
possible.  It will use local tlb purge as much as possible. Though the
conditions to use local tlb purge is pretty restrictive.  One of the
side effect of having flush tlb range instruction on ia64 is that
kernel don't get a chance to clear out cpu_vm_mask.  On ia64, this mask
is sticky and it will accumulate if process bounces around.  Thus
diminishing the possible use of ptc.l.  Thoughts?

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Acked-by: Jack Steiner <steiner@sgi.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-27 10:20:03 -08:00
Zhang, Yanmin
5e48521e86 [IA64] lazy_mmu_prot_update needs to be aware of huge pages
Function lazy_mmu_prot_update is also used on huge pages when it is called
by set_huge_ptep_writable, but it isn't aware of huge pages.

Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Acked-by: Ken Chen <kenneth.w.chen@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-27 10:15:41 -08:00
Larry Finger
d94606e058 [PATCH] Minor (janitorial) change to ieee80211
The attached patch removes a potential problem from ieee80211_wx.c, by changing the name of routine
ipw2100_translate_scan to ieee80211_translate_scan. The problem is minor as the routine is declared
static; however, if it were made global, it would pollute the namespace.

Signed-Off-By: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2006-03-27 12:07:02 -05:00
Linus Torvalds
329b10bb0f Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6:
  [SPARC64]: Fix off-by-1 error in TSB grow check.
2006-03-27 08:47:54 -08:00
Linus Torvalds
fdccffc6b7 Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
  [NET]: drop duplicate assignment in request_sock
  [IPSEC]: Fix tunnel error handling in ipcomp6
2006-03-27 08:47:29 -08:00
Linus Torvalds
4fa639123d Merge branch 'for-linus' of git://brick.kernel.dk/data/git/linux-2.6-block
* 'for-linus' of git://brick.kernel.dk/data/git/linux-2.6-block:
  [PATCH] Don't make debugfs depend on DEBUG_KERNEL
  [PATCH] Fix blktrace compile with sysfs not defined
  [PATCH] unused label in drivers/block/cciss.
  [BLOCK] increase size of disk stat counters
  [PATCH] blk_execute_rq_nowait-speedup
  [PATCH] ide-cd: quiet down GPCMD_READ_CDVD_CAPACITY failure
  [BLOCK] ll_rw_blk: kmalloc -> kzalloc conversion
  [PATCH] kzalloc() conversion in drivers/block
  [PATCH] update max_sectors documentation
2006-03-27 08:46:49 -08:00
NeilBrown
df5b89b323 [PATCH] md: Convert reconfig_sem to reconfig_mutex
... being careful that mutex_trylock is inverted wrt down_trylock

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:03 -08:00
Arjan van de Ven
48c9c27b8b [PATCH] sem2mutex: drivers/md
Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:03 -08:00
NeilBrown
2f889129de [PATCH] md: Restore 'remaining' count when retrying an write operation
When retrying a write due to barrier failure, we don't reset 'remaining', so
it goes negative and never hits 0 again.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:03 -08:00
NeilBrown
8ddeeae51f [PATCH] md: Fix md grow/size code to correctly find the maximum available space
An md array can be asked to change the amount of each device that it is using,
and in particular can be asked to use the maximum available space.  This
currently only works if the first device is not larger than the rest.  As
'size' gets changed and so 'fit' becomes wrong.  So check if a 'fit' is
required early and don't corrupt it.

Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:03 -08:00
NeilBrown
f6344757a9 [PATCH] md: Remove bi_end_io call out from under a spinlock
raid5 overloads bi_phys_segments to count the number of blocks that the
request was broken in to so that it knows when the bio is completely handled.

Accessing this must always be done under a spinlock.  In one case we also call
bi_end_io under that spinlock, which probably isn't ideal as bi_end_io could
be expensive (even though it isn't allowed to sleep).

So we reducde the range of the spinlock to just accessing bi_phys_segments.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:03 -08:00
NeilBrown
b3b46be38a [PATCH] md: Remove some stray semi-colons after functions called in macro..
wait_event_lock_irq puts a ';' after its usage of the 4th arg, so we don't
need to.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:02 -08:00
NeilBrown
df8e7f7639 [PATCH] md: Improve comments about locking situation in raid5 make_request
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:02 -08:00
NeilBrown
e464eafdb4 [PATCH] md: Support suspending of IO to regions of an md array
This allows user-space to access data safely.  This is needed for raid5
reshape as user-space needs to take a backup of the first few stripes before
allowing reshape to commence.

It will also be useful in cluster-aware raid1 configurations so that all
cluster members can leave a section of the array untouched while a
resync/recovery happens.

A 'start' and 'end' of the suspended range are written to 2 sysfs attributes.
Note that only one range can be suspended at a time.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:02 -08:00
NeilBrown
16484bf596 [PATCH] md: Make 'reshape' a possible sync_action action
This allows reshape to be triggerred via sysfs (which is the only way to start
it happening).

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:02 -08:00
NeilBrown
63c70c4f3a [PATCH] md: Split reshape handler in check_reshape and start_reshape
check_reshape checks validity and does things that can be done instantly -
like adding devices to raid1.  start_reshape initiates a restriping process to
convert the whole array.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:02 -08:00
NeilBrown
b578d55fdd [PATCH] md: Only checkpoint expansion progress occasionally
Instead of checkpointing at each stripe, only checkpoint when a new write
would overwrite uncheckpointed data.  Block any write to the uncheckpointed
area.  Arbitrarily checkpoint at least every 3Meg.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:02 -08:00
NeilBrown
f67055780c [PATCH] md: Checkpoint and allow restart of raid5 reshape
We allow the superblock to record an 'old' and a 'new' geometry, and a
position where any conversion is up to.  The geometry allows for changing
chunksize, layout and level as well as number of devices.

When using verion-0.90 superblock, we convert the version to 0.91 while the
conversion is happening so that an old kernel will refuse the assemble the
array.  For version-1, we use a feature bit for the same effect.

When starting an array we check for an incomplete reshape and restart the
reshape process if needed.  If the reshape stopped at an awkward time (like
when updating the first stripe) we refuse to assemble the array, and let
user-space worry about it.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:01 -08:00
NeilBrown
292695531a [PATCH] md: Final stages of raid5 expand code
This patch adds raid5_reshape and end_reshape which will start and finish the
reshape processes.

raid5_reshape is only enabled in CONFIG_MD_RAID5_RESHAPE is set, to discourage
accidental use.

Read the 'help' for the CONFIG_MD_RAID5_RESHAPE entry.

and Make sure that you have backups, just in case.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:01 -08:00
NeilBrown
ccfcc3c10b [PATCH] md: Core of raid5 resize process
This patch provides the core of the resize/expand process.

sync_request notices if a 'reshape' is happening and acts accordingly.

It allocated new stripe_heads for the next chunk-wide-stripe in the target
geometry, marking them STRIPE_EXPANDING.

Then it finds which stripe heads in the old geometry can provide data needed
by these and marks them STRIPE_EXPAND_SOURCE.  This causes stripe_handle to
read all blocks on those stripes.

Once all blocks on a STRIPE_EXPAND_SOURCE stripe_head are read, any that are
needed are copied into the corresponding STRIPE_EXPANDING stripe_head.  Once a
STRIPE_EXPANDING stripe_head is full, it is marks STRIPE_EXPAND_READY and then
is written out and released.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:01 -08:00
NeilBrown
7ecaa1e6a1 [PATCH] md: Infrastructure to allow normal IO to continue while array is expanding
We need to allow that different stripes are of different effective sizes, and
use the appropriate size.  Also, when a stripe is being expanded, we must
block any IO attempts until the stripe is stable again.

Key elements in this change are:
 - each stripe_head gets a 'disk' field which is part of the key,
   thus there can sometimes be two stripe heads of the same area of
   the array, but covering different numbers of devices.  One of these
   will be marked STRIPE_EXPANDING and so won't accept new requests.
 - conf->expand_progress tracks how the expansion is progressing and
   is used to determine whether the target part of the array has been
   expanded yet or not.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:01 -08:00
NeilBrown
ad01c9e375 [PATCH] md: Allow stripes to be expanded in preparation for expanding an array
Before a RAID-5 can be expanded, we need to be able to expand the stripe-cache
data structure.

This requires allocating new stripes in a new kmem_cache.  If this succeeds,
we copy cache pages over and release the old stripes and kmem_cache.

We then allocate new pages.  If that fails, we leave the stripe cache at it's
new size.  It isn't worth the effort to shrink it back again.

Unfortuanately this means we need two kmem_cache names as we, for a short
period of time, we have two kmem_caches.  So they are raid5/%s and
raid5/%s-alt

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:01 -08:00
NeilBrown
b55e6bfcd2 [PATCH] md: Split disks array out of raid5 conf structure so it is easier to grow
The remainder of this batch implements raid5 reshaping.  Currently the only
shape change that is supported is added a device, but it is envisioned that
changing the chunksize and layout will also be supported, as well as changing
the level (e.g.  1->5, 5->6).

The reshape process naturally has to move all of the data in the array, and so
should be used with caution.  It is believed to work, and some testing does
support this, but wider testing would be great for increasing my confidence.

You will need a version of mdadm newer than 2.3.1 to make use of raid5 growth.
 This is because mdadm need to take a copy of a 'critical section' at the
start of the array incase there is a crash at an awkward moment.  On restart,
mdadm will restore the critical section and allow reshape to continue.

I hope to release a 2.4-pre by early next week - it still needs a little more
polishing.

This patch:

Previously the array of disk information was included in the raid5 'conf'
structure which was allocated to an appropriate size.  This makes it awkward
to change the size of that array.  So we split it off into a separate
kmalloced array which will require a little extra indexing, but is much easier
to grow.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:01 -08:00