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1664 commits

Author SHA1 Message Date
Akinobu Mita
55af6bb509 md: convert cpu notifier to return encapsulate errno value
By the previous modification, the cpu notifier can return encapsulate
errno value.  This converts the cpu notifiers for raid5.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:48 -07:00
Linus Torvalds
e8bebe2f71 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (69 commits)
  fix handling of offsets in cris eeprom.c, get rid of fake on-stack files
  get rid of home-grown mutex in cris eeprom.c
  switch ecryptfs_write() to struct inode *, kill on-stack fake files
  switch ecryptfs_get_locked_page() to struct inode *
  simplify access to ecryptfs inodes in ->readpage() and friends
  AFS: Don't put struct file on the stack
  Ban ecryptfs over ecryptfs
  logfs: replace inode uid,gid,mode initialization with helper function
  ufs: replace inode uid,gid,mode initialization with helper function
  udf: replace inode uid,gid,mode init with helper
  ubifs: replace inode uid,gid,mode initialization with helper function
  sysv: replace inode uid,gid,mode initialization with helper function
  reiserfs: replace inode uid,gid,mode initialization with helper function
  ramfs: replace inode uid,gid,mode initialization with helper function
  omfs: replace inode uid,gid,mode initialization with helper function
  bfs: replace inode uid,gid,mode initialization with helper function
  ocfs2: replace inode uid,gid,mode initialization with helper function
  nilfs2: replace inode uid,gid,mode initialization with helper function
  minix: replace inode uid,gid,mode init with helper
  ext4: replace inode uid,gid,mode init with helper
  ...

Trivial conflict in fs/fs-writeback.c (mark bitfields unsigned)
2010-05-21 19:37:45 -07:00
NeilBrown
19fdb9eefb Merge commit '3ff195b011d7decf501a4d55aeed312731094796' into for-linus
Conflicts:
	drivers/md/md.c

- Resolved conflict in md_update_sb
- Added extra 'NULL' arg to new instance of sysfs_get_dirent.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-22 08:31:36 +10:00
Christoph Hellwig
8018ab0574 sanitize vfs_fsync calling conventions
Now that the last user passing a NULL file pointer is gone we can remove
the redundant dentry argument and associated hacks inside vfs_fsynmc_range.

The next step will be removig the dentry argument from ->fsync, but given
the luck with the last round of method prototype changes I'd rather
defer this until after the main merge window.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-21 18:31:21 -04:00
Eric W. Biederman
3ff195b011 sysfs: Implement sysfs tagged directory support.
The problem.  When implementing a network namespace I need to be able
to have multiple network devices with the same name.  Currently this
is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and
potentially a few other directories of the form /sys/ ... /net/*.

What this patch does is to add an additional tag field to the
sysfs dirent structure.  For directories that should show different
contents depending on the context such as /sys/class/net/, and
/sys/devices/virtual/net/ this tag field is used to specify the
context in which those directories should be visible.  Effectively
this is the same as creating multiple distinct directories with
the same name but internally to sysfs the result is nicer.

I am calling the concept of a single directory that looks like multiple
directories all at the same path in the filesystem tagged directories.

For the networking namespace the set of directories whose contents I need
to filter with tags can depend on the presence or absence of hotplug
hardware or which modules are currently loaded.  Which means I need
a simple race free way to setup those directories as tagged.

To achieve a reace free design all tagged directories are created
and managed by sysfs itself.

Users of this interface:
- define a type in the sysfs_tag_type enumeration.
- call sysfs_register_ns_types with the type and it's operations
- sysfs_exit_ns when an individual tag is no longer valid

- Implement mount_ns() which returns the ns of the calling process
  so we can attach it to a sysfs superblock.
- Implement ktype.namespace() which returns the ns of a syfs kobject.

Everything else is left up to sysfs and the driver layer.

For the network namespace mount_ns and namespace() are essentially
one line functions, and look to remain that.

Tags are currently represented a const void * pointers as that is
both generic, prevides enough information for equality comparisons,
and is trivial to create for current users, as it is just the
existing namespace pointer.

The work needed in sysfs is more extensive.  At each directory
or symlink creating I need to check if the directory it is being
created in is a tagged directory and if so generate the appropriate
tag to place on the sysfs_dirent.  Likewise at each symlink or
directory removal I need to check if the sysfs directory it is
being removed from is a tagged directory and if so figure out
which tag goes along with the name I am deleting.

Currently only directories which hold kobjects, and
symlinks are supported.  There is not enough information
in the current file attribute interfaces to give us anything
to discriminate on which makes it useless, and there are
no potential users which makes it an uninteresting problem
to solve.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
NeilBrown
be6800a73a md: don't insist on valid event count for spare devices.
Devices which know that they are spares do not really need to have
an event count that matches the rest of the array, so there are no
data-in-sync issues. It is enough that the uuid matches.
So remove the requirement that the event count is up-to-date.

We currently still write out and event count on spares, but this
allows us in a year or 3 to stop doing that completely.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:28:01 +10:00
NeilBrown
a8707c08f4 md: simplify updating of event count to sometimes avoid updating spares.
When updating the event count for a simple clean <-> dirty transition,
we try to avoid updating the spares so they can safely spin-down.
As the event_counts across an array must be +/- 1, this means
decrementing the event_count on a dirty->clean transition.
This is not always safe and we have to avoid the unsafe time.
We current do this with a misguided idea about it being safe or
not depending on whether the event_count is odd or even.  This
approach only works reliably in a few common instances, but easily
falls down.

So instead, simply keep internal state concerning whether it is safe
or not, and always assume it is not safe when an array is first
assembled.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:28:01 +10:00
Gabriele A. Trombetti
7b0bb5368a md/raid6: Fix raid-6 read-error correction in degraded state
Fix: Raid-6 was not trying to correct a read-error when in
singly-degraded state and was instead dropping one more device, going to
doubly-degraded state. This patch fixes this behaviour.

Tested-by: Janos Haar <janos.haar@netcenter.hu>
Signed-off-by: Gabriele A. Trombetti <g.trombetti.lkrnl1213@logicschema.com>
Reported-by: Janos Haar <janos.haar@netcenter.hu>
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
2010-05-18 15:28:00 +10:00
NeilBrown
75a73a29e5 md: restore ability of spare drives to spin down.
Some time ago we stopped the clean/active metadata updates
from being written to a 'spare' device in most cases so that
it could spin down and say spun down.  Device failure/removal
etc are still recorded on spares.

However commit 51d5668cb2 broke this 50% of the time,
depending on whether the event count is even or odd.
The change log entry said:

   This means that the alignment between 'odd/even' and
    'clean/dirty' might take a little longer to attain,

how ever the code makes no attempt to create that alignment, so it
could take arbitrarily long.

So when we find that clean/dirty is not aligned with odd/even,
force a second metadata-update immediately.  There are already cases
where a second metadata-update is needed immediately (e.g. when a
device fails during the metadata update).  We just piggy-back on that.

Reported-by: Joe Bryant <tenminjoe@yahoo.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
2010-05-18 15:28:00 +10:00
NeilBrown
af3a2cd6b8 md: Fix read balancing in RAID1 and RAID10 on drives > 2TB
read_balance uses a "unsigned long" for a sector number which
will get truncated beyond 2TB.
This will cause read-balancing to be non-optimal, and can cause
data to be read from the 'wrong' branch during a resync.  This has a
very small chance of returning wrong data.

Reported-by: Jordan Russell <jr-list-2010@quo.to>
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:28:00 +10:00
NeilBrown
2dc40f8094 md/linear: standardise all printk messages
md/linear:mdname:

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:59 +10:00
NeilBrown
b5a20961f3 md/raid0: tidy up printk messages.
All messages now start
   md/raid0:md-device-name:

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:59 +10:00
NeilBrown
128595ed6f md/raid10: tidy up printk messages.
All raid10 printk messages now start
   md/raid10:md-device-name:

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:59 +10:00
NeilBrown
9dd1e2faf7 md/raid1: improve printk messages
Make sure the array name is included in a uniform way in all printk
messages.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:59 +10:00
NeilBrown
0c55e02259 md/raid5: improve consistency of error messages.
Many 'printk' messages from the raid456 module mention 'raid5' even
though it may be a 'raid6' or even 'raid4' array.  This can cause
confusion.
Also the actual array name is not always reported and when it is
it is not reported consistently.

So change all the messages to start:
    md/raid:%s:
where '%s' becomes e.g. md3 to identify the particular array.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:58 +10:00
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
Dan Williams
f2859af671 md: allow integers to be passed to md/level
e.g. allow md to interpret 'echo 4 > md/level' as a request for raid4.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-18 15:27:58 +10:00
Dan Williams
bb7f8d2217 md: notify mdstat waiters of level change
Level modifications change the output of mdstat.  The mdmon manager
thread is interested in these events for external metadata management.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-18 15:27:57 +10:00
Dan Williams
f1b29bcae1 md/raid4: permit raid0 takeover
For consistency allow raid4 to takeover raid0 in addition to raid5 (with a
raid4 layout).

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-18 15:27:57 +10:00
NeilBrown
e555190d82 md/raid1: delay reads that could overtake behind-writes.
When a raid1 array is configured to support write-behind
on some devices, it normally only reads from other devices.
If all devices are write-behind (because the rest have failed)
it is possible for a read request to be serviced before a
behind-write request, which would appear as data corruption.

So when forced to read from a WriteMostly device, wait for any
write-behind to complete, and don't start any more behind-writes.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:57 +10:00
NeilBrown
d754c5ae1f md/raid1: fix confusing 'redirect sector' message.
This message seems to suggest the named device is the one on which a
read failed, however it is actually the device that the read will be
redirected to.
So make the message a little clearer.

Reported-by: Tim Burgess <ozburgess@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:56 +10:00
NeilBrown
9e35b99c7e md: don't unregister the thread in mddev_suspend
This is
 - unnecessary because mddev_suspend is always followed by a call to
   ->stop, and each ->stop unregisters the thread, and
 - a problem as it makes it awkwards to suspend and then resume a
   device as we will want later.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:56 +10:00
NeilBrown
fafd7fb052 md: factor out init code for an mddev
This is a simple factorisation that makes mddev_find easier to read.


Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:55 +10:00
NeilBrown
21a52c6d05 md: pass mddev to make_request functions rather than request_queue
We used to pass the personality make_request function direct
to the block layer so the first argument had to be a queue.
But now we have the intermediary md_make_request so it makes
at lot more sense to pass a struct mddev_s.
It makes it possible to have an mddev without its own queue too.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:55 +10:00
NeilBrown
cca9cf90c5 md: call md_stop_writes from md_stop
This moves the call to the other side of set_readonly, but that should
not be an issue.
This encapsulates in 'md_stop' all of the functionality for internally
stopping the array, leaving all the interactions with externalities
(sysfs, request_queue, gendisk) in do_md_stop.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:54 +10:00
NeilBrown
a4bd82d0d0 md: split md_set_readonly out of do_md_stop
Using do_md_stop to set an array to read-only is a little confusing.
Now most of the common code has been factored out, split
md_set_readonly off in to a separate function.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:54 +10:00
NeilBrown
a047e12540 md: factor md_stop_writes out of do_md_stop.
Further refactoring of do_md_stop.
This one requires some explanation as it takes code from different
places in do_md_stop, so some re-ordering happens.

We only get into this part of do_md_stop if there are no active opens
of the device, so no writes can be happening and the device must have
been flushed.  In md_stop_writes we want to stop any internal sources
of writes - i.e. resync - and flush out the metadata.

The only code that was previously before some of this code is
code to clean up the queue, the mddev, the gendisk, or sysfs, all
of which is probably better after code that makes active changes (i.e.
triggers writes).

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:54 +10:00
NeilBrown
6177b472ab md: start to refactor do_md_stop
do_md_stop is large and clunky, so hard to understand.

This is a first step of refactoring, pulling two simple
sub-functions out.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:53 +10:00
NeilBrown
fe60b01428 md: factor do_md_run to separate accesses to ->gendisk
As part of relaxing the binding between an mddev and gendisk,
we separate do_md_run into two functions.
  md_run does all the work internal to md
  do_md_run calls md_run and makes and changes to gendisk
     that are required.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:53 +10:00
NeilBrown
b821eaa572 md: remove ->changed and related code.
We set ->changed to 1 and call check_disk_change at the end
of md_open so that bd_invalidated would be set and thus
partition rescan would happen appropriately.

Now that we call revalidate_disk directly, which sets bd_invalidates,
that indirection is no longer needed and can be removed.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:53 +10:00
NeilBrown
49ce6cea85 md: don't reference gendisk in getgeo
Using ->array_sectors rather than get_capacity() is more
direct and is a step towards relaxing the tight connection
between mddev and gendisk.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:52 +10:00
NeilBrown
490773268c md: move io accounting out of personalities into md_make_request
While I generally prefer letting personalities do as much as possible,
given that we have a central md_make_request anyway we may as well use
it to simplify code.
Also this centralises knowledge of ->gendisk which will help later.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:52 +10:00
NeilBrown
2b7f22284d md/raid5: small tidyup in raid5_align_endio
Diving through ->queue to find mddev is unnecessarily complex - there
is an easier path to finding mddev, so use that.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:50 +10:00
NeilBrown
a78d38a1a1 md: add support for raid5 to raid4 conversion
This is unlikely to be wanted, but we may as well provide it
for completeness.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:49 +10:00
Maciej Trela
5cac7861b2 md: notify level changes through sysfs.
Level changes can be very significant, so make sure
to notify them via sysfs.

Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:49 +10:00
NeilBrown
233fca36bb md: Relax checks on ->max_disks when external metadata handling is used.
When metadata is being managed by user-space, md doesn't know
what the maximum number of devices allowed in an array is
so ->max_disks is 0.  In this case we should allow any (+ve)
number of disks.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:49 +10:00
Maciej Trela
b71031076e md: Correctly handle device removal via sysfs
Writing "none" to "../md/dev-xx/slot" removes that device
from being an active part of the array, but it didn't
set ->raid_disk to -1 to record this fact.


Signed-off-by: Maciej Trela <Maciej.Trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:48 +10:00
Trela, Maciej
dab8b29248 md: Add support for Raid0->Raid10 takeover
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:48 +10:00
Trela, Maciej
9af204cf72 md: Add support for Raid5->Raid0 and Raid10->Raid0 takeover
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:48 +10:00
Trela Maciej
54071b3808 md:Add support for Raid0->Raid5 takeover
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:47 +10:00
NeilBrown
84707f38e7 md: don't use mddev->raid_disks in raid0 or raid10 while array is active.
In a subsequent patch we will make it possible to change
mddev->raid_disks while a RAID0 or RAID10 array is active.  This is
part of the process of reshaping such an array.

This means that we cannot use this value while processes requests
(it is OK to use it during initialisation as we are locked against
changes then).
Both RAID0 and RAID10 have the same value stored in the private data
structure, so use that value instead.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:47 +10:00
NeilBrown
c0cc75f84e md: discard StateChanged device flag.
This was needed when sysfs files could only be 'notified'
from process context.  Now that we have sys_notify_direct,
we can call it directly from an interrupt.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:47 +10:00
H Hartley Sweeten
7b92813c3c drivers/md: Remove unnecessary casts of void *
void pointers do not need to be cast to other pointer types.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:46 +10:00
Paul Clements
696fcd535b md: expose max value of behind writes counter
Keep track of the maximum number of concurrent write-behind requests
for an md array and exposed this number in sysfs at
   md/bitmap/max_backlog_used

Writing any value to this file will clear it.

This allows userspace to be involved in tuning bitmap/backlog.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:46 +10:00
NeilBrown
ee8b81b03d md: remove some dead fields from mddev_s
These fields have never been used.
commit 4b6d287f62
added them, but also added identical files to bitmap_super_s,
and only used the latter.

So remove these unused fields.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:45 +10:00
NeilBrown
964147d5c8 md/raid1: fix counting of write targets.
There is a very small race window when writing to a
RAID1 such that if a device is marked faulty at exactly the wrong
time, the write-in-progress will not be sent to the device,
but the bitmap (if present) will be updated to say that
the write was sent.

Then if the device turned out to still be usable as was re-added
to the array, the bitmap-based-resync would skip resyncing that
block, possibly leading to corruption.  This would only be a problem
if no further writes were issued to that area of the device (i.e.
that bitmap chunk).

Suitable for any pending -stable kernel.

Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18 15:27:13 +10:00
NeilBrown
a64c876fd3 md: manage redundancy group in sysfs when changing level.
Some levels expect the 'redundancy group' to be present,
others don't.
So when we change level of an array we might need to
add or remove this group.

This requires fixing up the current practice of overloading ->private
to indicate (when ->pers == NULL) that something needs to be removed.
So create a new ->to_remove to fill that role.

When changing levels, we may need to add or remove attributes.  When
changing RAID5 -> RAID6, we both add and remove the same thing.  It is
important to catch this and optimise it out as the removal is delayed
until a lock is released, so trying to add immediately would cause
problems.


Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-17 14:45:40 +10:00
NeilBrown
b6eb127d27 md: remove unneeded sysfs files more promptly
When an array is stopped we need to remove some
sysfs files which are dependent on the type of array.

We need to delay that deletion as deleting them while holding
reconfig_mutex can lead to deadlocks.

We currently delay them until the array is completely destroyed.
However it is possible to deactivate and then reactivate the array.
It is also possible to need to remove sysfs files when changing level,
which can potentially happen several times before an array is
destroyed.

So we need to delete these files more promptly: as soon as
reconfig_mutex is dropped.

We need to ensure this happens before do_md_run can restart the array,
so we use open_mutex for some extra locking.  This is not deadlock
prone.

Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-17 14:40:07 +10:00
NeilBrown
ef2f80ff73 md/linear: avoid possible oops and array stop
Since commit ef286f6fa6
it has been important that each personality clears
->private in the ->stop() function, or sets it to a
attribute group to be removed.
linear.c doesn't.  This can sometimes lead to an oops,
though it doesn't always.

Suitable for 2.6.33-stable and 2.6.34.

Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
2010-05-17 14:38:18 +10:00
Dan Williams
e221835046 md: set mddev readonly flag on blkdev BLKROSET ioctl
When the user sets the block device to readwrite then the mddev should
follow suit.  Otherwise, the BUG_ON in md_write_start() will be set to
trigger.

The reverse direction, setting mddev->ro to match a set readonly
request, can be ignored because the blkdev level readonly flag precludes
the need to have mddev->ro set correctly.  Nevermind the fact that
setting mddev->ro to 1 may fail if the array is in use.

Cc: <stable@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-12 08:25:37 +10:00