Commit Graph

629 Commits

Author SHA1 Message Date
Alasdair G Kergon 4b832e8de2 [PATCH] dm snapshot: tidy pe ref counting
Rename sibling_count to ref_count and introduce get and put functions.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Alasdair G Kergon ca3a931fd3 [PATCH] dm snapshot: add workqueue
Add a workqueue so that I/O can be queued up to be flushed from a separate
thread (e.g.  if local interrupts are disabled).

A new per-snapshot spinlock pe_lock is introduced to protect queued_bios.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Alasdair G Kergon 9d493fa8c9 [PATCH] dm snapshot: tidy pending_complete
This patch rearranges the pending_complete() code so that the functional
changes in subsequent patches are clearer.

By consolidating the error and the non-error paths, we can move
error_snapshot_bios() and __flush_bios() in line.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Alasdair G Kergon ba40a2aa6e [PATCH] dm snapshot: tidy snapshot_map
This patch rearranges the snapshot_map code so that the functional changes in
subsequent patches are clearer.

The only functional change is to replace the existing read lock with a write
lock which the next patch needs.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Mark McLoughlin 927ffe7c9a [PATCH] dm snapshot: fix metadata writing when suspending
When suspending a device-mapper device, dm_suspend() sleeps until all
necessary I/O is completed.  This state is triggered by a callback from
persistent_commit().  But some I/O can still be issued *after* the callback
(to prepare the next metadata area for use if the current one is full).  This
patch delays the callback until after that I/O is complete.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Mark McLoughlin e4ff496db7 [PATCH] dm snapshot: make read and write exception functions void
read_exception() and write_exception() only return an error if supplied with
an out-of-range index.  If this ever happens it's the result of a bug in the
calling code so we handle this with an assertion and remove the error handling
in the callers.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Mark McLoughlin f9cea4f707 [PATCH] dm snapshot: fix metadata error handling
Fix the error handling when store.read_metadata is called: the error should be
returned immediately.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Mark McLoughlin 4c7e3bf44d [PATCH] dm snapshot: allow zero chunk_size
The chunk size of snapshots cannot be changed so it is redundant to require it
as a parameter when activating an existing snapshot.  Allow a value of zero in
this case and ignore it.  For a new snapshot, use a default value if zero is
specified.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Milan Broz 92c060a692 [PATCH] dm snapshot: fix invalidation ENOMEM
Fix ENOMEM error sign.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Ishai Rabinovitz e3f6ac6123 [PATCH] dm: fix alloc_dev error path
While reading the code I found a bug in the error path in alloc_dev in dm.c

When blk_alloc_queue fails there is no call to free_minor.

This patch fixes the problem.

Signed-off-by: Ishai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:14 -07:00
Milan Broz e90dae1f58 [PATCH] dm: support ioctls on mapped devices: fix with fake file
The new ioctl code passes the wrong file pointer to the underlying device.
No file pointer is available so make a temporary fake one.

ioctl_by_bdev() does set_fs(KERNEL_DS) so it's for ioctls originating
within the kernel and unsuitable here.  We are processing ioctls that
originated in userspace and mapping them to different devices.  Fixing the
existing callers that pass a NULL file struct and consolidating the
fake_file users are separate matters to solve in later patches.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:13 -07:00
Alasdair G Kergon 7006f6eca8 [PATCH] dm: export blkdev_driver_ioctl
Export blkdev_driver_ioctl for device-mapper.

If we get as far as the device-mapper ioctl handler, we know the ioctl is not
a standard block layer BLK* one, so we don't need to check for them a second
time and can call blkdev_driver_ioctl() directly.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:13 -07:00
Milan Broz 9af4aa30b7 [PATCH] dm mpath: support ioctls
When an ioctl is performed on a multipath device simply pass it on to the
underlying block device through current_path.  If current path is not yet
selected, select it.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:13 -07:00
Milan Broz ab17ffa440 [PATCH] dm linear: support ioctls
When an ioctl is performed on a device with a linear target, simply pass it on
to the underlying block device.

Note that the ioctl will pass through the filtering in blkdev_ioctl() twice.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:13 -07:00
Milan Broz aa129a2247 [PATCH] dm: support ioctls on mapped devices
Extend the core device-mapper infrastructure to accept arbitrary ioctls on a
mapped device provided that it has exactly one target and it is capable of
supporting ioctls.

[We can't use unlocked_ioctl because we need 'inode': 'file' might be NULL.
Is it worth changing this?]

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

Arnd Bergmann <arnd@arndb.de> wrote:

> Am Wednesday 21 June 2006 21:31 schrieb Alasdair G Kergon:
> > static struct block_device_operations dm_blk_dops = {
> > .open = dm_blk_open,
> > .release = dm_blk_close,
> > +.ioctl = dm_blk_ioctl,
> > .getgeo = dm_blk_getgeo,
> > .owner = THIS_MODULE
>
> I guess this also needs a ->compat_ioctl method, otherwise it won't
> work for ioctl numbers that have a compat_ioctl implementation in the
> low-level device driver.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:13 -07:00
David Howells 9361401eb7 [PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer.  Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.

This patch does the following:

 (*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
     support.

 (*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
     an item that uses the block layer.  This includes:

     (*) Block I/O tracing.

     (*) Disk partition code.

     (*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.

     (*) The SCSI layer.  As far as I can tell, even SCSI chardevs use the
     	 block layer to do scheduling.  Some drivers that use SCSI facilities -
     	 such as USB storage - end up disabled indirectly from this.

     (*) Various block-based device drivers, such as IDE and the old CDROM
     	 drivers.

     (*) MTD blockdev handling and FTL.

     (*) JFFS - which uses set_bdev_super(), something it could avoid doing by
     	 taking a leaf out of JFFS2's book.

 (*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
     linux/elevator.h contingent on CONFIG_BLOCK being set.  sector_div() is,
     however, still used in places, and so is still available.

 (*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
     parts of linux/fs.h.

 (*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.

 (*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.

 (*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
     is not enabled.

 (*) fs/no-block.c is created to hold out-of-line stubs and things that are
     required when CONFIG_BLOCK is not set:

     (*) Default blockdev file operations (to give error ENODEV on opening).

 (*) Makes some /proc changes:

     (*) /proc/devices does not list any blockdevs.

     (*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.

 (*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.

 (*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
     given command other than Q_SYNC or if a special device is specified.

 (*) In init/do_mounts.c, no reference is made to the blockdev routines if
     CONFIG_BLOCK is not defined.  This does not prohibit NFS roots or JFFS2.

 (*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
     error ENOSYS by way of cond_syscall if so).

 (*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
     CONFIG_BLOCK is not set, since they can't then happen.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:52:31 +02:00
Jens Axboe 4aff5e2333 [PATCH] Split struct request ->flags into two parts
Right now ->flags is a bit of a mess: some are request types, and
others are just modifiers. Clean this up by splitting it into
->cmd_type and ->cmd_flags. This allows introduction of generic
Linux block message types, useful for sending generic Linux commands
to block devices.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:23:37 +02:00
Rik Snel 3c164bd815 [BLOCK] dm-crypt: trivial comment improvements
Just some minor comment nits.

- little-endian is better than low-endian
- and since it is called essiv everywere it should also be essiv
  in the comments (and not ess_iv)

Signed-off-by: Rik Snel <rsnel@cube.dyndns.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-09-21 11:46:27 +10:00
Herbert Xu 3505868791 [CRYPTO] users: Use crypto_hash interface instead of crypto_digest
This patch converts all remaining crypto_digest users to use the new
crypto_hash interface.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-09-21 11:46:21 +10:00
Herbert Xu d1806f6a97 [BLOCK] dm-crypt: Use block ciphers where applicable
This patch converts dm-crypt to use the new block cipher type where
applicable.  It also changes simple cipher operations to use the new
encrypt_one/decrypt_one interface.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-09-21 11:46:13 +10:00
NeilBrown ddac7c7e3a [PATCH] md: Fix issues with referencing rdev in md/raid1
We need to be careful when referencing mirrors[i].rdev.  It can disappear
under us at various times.

So:
  fix a couple of problem places.
  comment a couple of non-problem places
  move an 'atomic_add' which deferences rdev down a little
    way to some where where it is sure to not be NULL.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01 11:39:08 -07:00
NeilBrown 6394cca548 [PATCH] md: fix recent breakage of md/raid1 array checking
A recent patch broke the ability to do a user-request check of a raid1.
This patch fixes the breakage and also moves a comment that was dislocated
by the same patch.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27 11:01:31 -07:00
NeilBrown 8469219596 [PATCH] md: avoid backward event updates in md superblock when degraded.
If we
  - shut down a clean array,
  - restart with one (or more) drive(s) missing
  - make some changes
  - pause, so that they array gets marked 'clean',
the event count on the superblock of included drives
will be the same as that of the removed drives.
So adding the removed drive back in will cause it
to be included with no resync.

To avoid this, we only update the eventcount backwards when the array
is not degraded.  In this case there can (should) be no non-connected
drives that we can get confused with, and this is the particular case
where updating-backwards is valuable.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27 11:01:31 -07:00
Daniel Kobras c06aad854f [PATCH] dm: Fix deadlock under high i/o load in raid1 setup.
On an nForce4-equipped machine with two SATA disk in raid1 setup using dmraid,
we experienced frequent deadlock of the system under high i/o load.  'cat
/dev/zero > ~/zero' was the most reliable way to reproduce them: Randomly
after a few GB, 'cp' would be left in 'D' state along with kjournald and
kmirrord.  The functions cp and kjournald were blocked in did vary, but
kmirrord's wchan always pointed to 'mempool_alloc()'.  We've seen this pattern
on 2.6.15 and 2.6.17 kernels.  http://lkml.org/lkml/2005/4/20/142 indicates
that this problem has been around even before.

So much for the facts, here's my interpretation: mempool_alloc() first tries
to atomically allocate the requested memory, or falls back to hand out
preallocated chunks from the mempool.  If both fail, it puts the calling
process (kmirrord in this case) on a private waitqueue until somebody refills
the pool.  Where the only 'somebody' is kmirrord itself, so we have a
deadlock.

I worked around this problem by falling back to a (blocking) kmalloc when
before kmirrord would have ended up on the waitqueue.  This defeats part of
the benefits of using the mempool, but at least keeps the system running.  And
it could be done with a two-line change.  Note that mempool_alloc() clears the
GFP_NOIO flag internally, and only uses it to decide whether to wait or return
an error if immediate allocation fails, so the attached patch doesn't change
behaviour in the non-deadlocking case.  Path is against current git
(2.6.18-rc4), but should apply to earlier versions as well.  I've tested on
2.6.15, where this patch makes the difference between random lockup and a
stable system.

Signed-off-by: Daniel Kobras <kobras@linux.de>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27 11:01:28 -07:00
Michal Miroslaw 485311a23c [PATCH] dm: BUG/OOPS fix
Fix BUG I tripped on while testing failover and multipathing.

BUG shows up on error path in multipath_ctr() when parse_priority_group()
fails after returning at least once without error.  The fix is to
initialize m->ti early - just after alloc()ing it.

BUG: unable to handle kernel NULL pointer dereference at virtual address 00000000
 printing eip:
c027c3d2
*pde = 00000000
Oops: 0000 [#3]
Modules linked in: qla2xxx ext3 jbd mbcache sg ide_cd cdrom floppy
CPU:    0
EIP:    0060:[<c027c3d2>]    Not tainted VLI
EFLAGS: 00010202   (2.6.17.3 #1)
EIP is at dm_put_device+0xf/0x3b
eax: 00000001   ebx: ee4fcac0   ecx: 00000000   edx: ee4fcac0
esi: ee4fc4e0   edi: ee4fc4e0   ebp: 00000000   esp: c5db3e78
ds: 007b   es: 007b   ss: 0068
Process multipathd (pid: 15912, threadinfo=c5db2000 task=ef485a90)
Stack: ec4eda40 c02816bd ee4fc4c0 00000000 f7e89498 f883e0bc c02816f6 f7e89480
       f7e8948c c0281801 ffffffea f7e89480 f883e080 c0281ffe 00000001 00000000
       00000004 dfe9cab8 f7a693c0 f883e080 f883e0c0 ca4b99c0 c027c6ee 01400000
Call Trace:
 <c02816bd> free_pgpaths+0x31/0x45  <c02816f6> free_priority_group+0x25/0x2e
 <c0281801> free_multipath+0x35/0x67  <c0281ffe> multipath_ctr+0x123/0x12d
 <c027c6ee> dm_table_add_target+0x11e/0x18b  <c027e5b4> populate_table+0x8a/0xaf
 <c027e62b> table_load+0x52/0xf9  <c027ec23> ctl_ioctl+0xca/0xfc
 <c027e5d9> table_load+0x0/0xf9  <c0152146> do_ioctl+0x3e/0x43
 <c0152360> vfs_ioctl+0x16c/0x178  <c01523b4> sys_ioctl+0x48/0x60
 <c01029b3> syscall_call+0x7/0xb
Code: 97 f0 00 00 00 89 c1 83 c9 01 80 e2 01 0f 44 c1 88 43 14 8b 04 24 59 5b 5e 5f 5d c3 53 89 c1 89 d3 ff 4a 08 0f 94 c0 84 c0 74 2a <8b> 01 8b 10 89 d8 e8 f6 fb ff ff 8b 03 8b 53 04 89 50 04 89 02
EIP: [<c027c3d2>] dm_put_device+0xf/0x3b SS:ESP 0068:c5db3e78

Signed-off-by: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-14 12:54:29 -07:00
NeilBrown f9abd1ace4 [PATCH] md: Fix a bug that recently crept into md/linear
A recent patch that allowed linear arrays to be reconfigured on-line
allowed in a bug which results in divide by zero - not all
mddev->array_size were converted to conf->array_size.

This patch finished the conversion and fixed the bug.

The offending patch was commit 7c7546ccf6.

Thanks to Simon Kirby <sim@netnation.com> for the bug report.

Cc: Simon Kirby <sim@netnation.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>
2006-08-06 08:57:46 -07:00
Andrew Morton d0a0a5ee7a [PATCH] md: fix oops in error-handling
During early MD setup (superblock reading), we don't have a personality yet.
But the error-handling code tries to dereference mddev->pers.  Fix.

Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:17 -07:00
NeilBrown d695043259 [PATCH] md: include sector number in messages about corrected read errors
This is generally useful, but particularly helps see if it is the same sector
that always needs correcting, or different ones.

[akpm@osdl.org: fix printk warnings]
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:17 -07:00
NeilBrown 67463acb64 [PATCH] md: require CAP_SYS_ADMIN for (re-)configuring md devices via sysfs
The ioctl requires CAP_SYS_ADMIN, so sysfs should too.  Note that we don't
require CAP_SYS_ADMIN for reading attributes even though the ioctl does.
There is no reason to limit the read access, and much of the information is
already available via /proc/mdstat

Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:17 -07:00
NeilBrown 80ca3a44f5 [PATCH] md: unify usage of symbolic names for perms
Some places we use number (0660) someplaces names (S_IRUGO).  Change all
numbers to be names, and change 0655 to be what it should be.

Also make some formatting more consistent.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:17 -07:00
NeilBrown 5e3db645f8 [PATCH] md: fix usage of wrong variable in raid1
Though it rarely matters, we should be using 's' rather than r1_bio->sector
here.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:17 -07:00
NeilBrown ae3c20ccf8 [PATCH] md: fix some small races in bitmap plugging in raid5
The comment gives more details, but I didn't quite have the sequencing write,
so there was room for races to leave bits unset in the on-disk bitmap for
short periods of 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>
2006-07-10 13:24:17 -07:00
NeilBrown 7c785b7a18 [PATCH] md: fix a plug/unplug race in raid5
When a device is unplugged, requests are moved from one or two (depending on
whether a bitmap is in use) queues to the main request queue.

So whenever requests are put on either of those queues, we should make sure
the raid5 array is 'plugged'.  However we don't.  We currently plug the raid5
queue just before putting requests on queues, so there is room for a race.  If
something unplugs the queue at just the wrong time, requests will be left on
the queue and nothing will want to unplug them.  Normally something else will
plug and unplug the queue fairly soon, but there is a risk that nothing will.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:16 -07:00
NeilBrown ff4e8d9a9f [PATCH] md: fix resync speed calculation for restarted resyncs
We introduced 'io_sectors' recently so we could count the sectors that causes
io during resync separate from sectors which didn't cause IO - there can be a
difference if a bitmap is being used to accelerate resync.

However when a speed is reported, we find the number of sectors processed
recently by subtracting an oldish io_sectors count from a current
'curr_resync' count.  This is wrong because curr_resync counts all sectors,
not just io sectors.

So, add a field to mddev to store the curren io_sectors separately from
curr_resync, and use that in the calculations.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:16 -07:00
NeilBrown 0b8c9de05c [PATCH] md: delay starting md threads until array is completely setup
When an array is started we start one or two threads (two if there is a
reshape or recovery that needs to be completed).

We currently start these *before* the array is completely set up and in
particular before queue->queuedata is set.  If the thread actually starts
very quickly on another CPU, we can end up dereferencing queue->queuedata
and oops.

This patch also makes sure we don't try to start a recovery if a reshape is
being restarted.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:16 -07:00
NeilBrown 31b65a0d38 [PATCH] md: set desc_nr correctly for version-1 superblocks
This has to be done in ->load_super, not ->validate_super

Without this, hot-adding devices to an array doesn't always
work right - though there is a work around in mdadm-2.5.2 to
make this less of an issue.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:16 -07:00
NeilBrown f4370781d8 [PATCH] md: possible fix for unplug problem
I have reports of a problem with raid5 which turns out to be because the raid5
device gets stuck in a 'plugged' state.  This shouldn't be able to happen as
3msec after it gets plugged it should get unplugged.  However it happens
none-the-less.  This patch fixes the problem and is a reasonable thing to do,
though it might hurt performance slightly in some cases.

Until I can find the real problem, we should probably have this workaround in
place.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:16 -07:00
Ingo Molnar 663d440eaa [PATCH] lockdep: annotate blkdev nesting
Teach special (recursive) locking code to the lock validator.

Effects on non-lockdep kernels:

- the introduction of the following function variants:

  extern struct block_device *open_partition_by_devnum(dev_t, unsigned);

  extern int blkdev_put_partition(struct block_device *);

  static int
  blkdev_get_whole(struct block_device *bdev, mode_t mode, unsigned flags);

 which on non-lockdep are the same as open_by_devnum(), blkdev_put()
 and blkdev_get().

- a subclass parameter to do_open(). [unused on non-lockdep]

- a subclass parameter to __blkdev_put(), which is a new internal
  function for the main blkdev_put*() functions. [parameter unused
  on non-lockdep kernels, except for two sanity check WARN_ON()s]

these functions carry no semantical difference - they only express
object dependencies towards the lockdep subsystem.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:10 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Linus Torvalds 602cada851 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/devfs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/devfs-2.6: (22 commits)
  [PATCH] devfs: Remove it from the feature_removal.txt file
  [PATCH] devfs: Last little devfs cleanups throughout the kernel tree.
  [PATCH] devfs: Rename TTY_DRIVER_NO_DEVFS to TTY_DRIVER_DYNAMIC_DEV
  [PATCH] devfs: Remove the tty_driver devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the line_driver devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the videodevice devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the gendisk devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the miscdevice devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
  [PATCH] devfs: Remove devfs_remove() function from the kernel tree
  [PATCH] devfs: Remove devfs_mk_cdev() function from the kernel tree
  [PATCH] devfs: Remove devfs_mk_bdev() function from the kernel tree
  [PATCH] devfs: Remove devfs_mk_symlink() function from the kernel tree
  [PATCH] devfs: Remove devfs_mk_dir() function from the kernel tree
  [PATCH] devfs: Remove devfs_*_tape() functions from the kernel tree
  [PATCH] devfs: Remove devfs support from the sound subsystem
  [PATCH] devfs: Remove devfs support from the ide subsystem.
  [PATCH] devfs: Remove devfs support from the serial subsystem
  [PATCH] devfs: Remove devfs from the init code
  [PATCH] devfs: Remove devfs from the partition code
  ...
2006-06-29 14:19:21 -07:00
Adrian Bunk cfb9e32f2f [PATCH] drivers/md/raid5.c: remove an unused variable
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:21 -07:00
Greg Kroah-Hartman 890fbae281 [PATCH] devfs: Last little devfs cleanups throughout the kernel tree.
Just removes a few unused #defines and fixes some comments due to
devfs now being gone.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:09 -07:00
Greg Kroah-Hartman ce7b0f46bb [PATCH] devfs: Remove the gendisk devfs_name field as it's no longer needed
And remove the now unneeded number field.
Also fixes all drivers that set these fields.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:08 -07:00
Greg Kroah-Hartman 96192ff1a9 [PATCH] devfs: Remove the miscdevice devfs_name field as it's no longer needed
Also fixes all drivers that set this field.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:08 -07:00
Greg Kroah-Hartman ff23eca3e8 [PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
Also fixes up all files that #include it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:08 -07:00
Greg Kroah-Hartman 8ab5e4c15b [PATCH] devfs: Remove devfs_remove() function from the kernel tree
Removes the devfs_remove() function and all callers of it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:07 -07:00
Greg Kroah-Hartman 1a715c5cf9 [PATCH] devfs: Remove devfs_mk_bdev() function from the kernel tree
Removes the devfs_mk_bdev() function and all callers of it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:06 -07:00
Greg Kroah-Hartman 95dc112a57 [PATCH] devfs: Remove devfs_mk_dir() function from the kernel tree
Removes the devfs_mk_dir() function and all callers of it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:06 -07:00
Adrian Bunk 0538195424 [PATCH] drivers/md/md.c: make code static
Make needlessly global code static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:40 -07:00
NeilBrown f655675b3f [PATCH] md: Allow the write_mostly flag to be set via sysfs
It appears in /sys/mdX/md/dev-YYY/state
and can be set or cleared by writing 'writemostly' or '-writemostly'
respectively.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:40 -07:00
NeilBrown a94213b1fa [PATCH] md: Allow resync_start to be set and queried via sysfs
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:40 -07:00
NeilBrown d4dbd0250e [PATCH] md: Allow raid 'layout' to be read and set via sysfs
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
NeilBrown 45dc2de1e5 [PATCH] md: Allow rdev state to be set via sysfs
The md/dev-XXX/state file can now be written:

 "faulty" simulates an error on the device
 "remove" removes the device from the array (if it is not busy)

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
NeilBrown 9e653b6342 [PATCH] md: Set/get state of array via sysfs
This allows the state of an md/array to be directly controlled via sysfs and
adds the ability to stop and array without tearing it down.

Array states/settings:

 clear
     No devices, no size, no level
     Equivalent to STOP_ARRAY ioctl
 inactive
     May have some settings, but array is not active
        all IO results in error
     When written, doesn't tear down array, but just stops it
 suspended (not supported yet)
     All IO requests will block. The array can be reconfigured.
     Writing this, if accepted, will block until array is quiescent
 readonly
     no resync can happen.  no superblocks get written.
     write requests fail
 read-auto
     like readonly, but behaves like 'clean' on a write request.

 clean - no pending writes, but otherwise active.
     When written to inactive array, starts without resync
     If a write request arrives then
       if metadata is known, mark 'dirty' and switch to 'active'.
       if not known, block and switch to write-pending
     If written to an active array that has pending writes, then fails.
 active
     fully active: IO and resync can be happening.
     When written to inactive array, starts with resync

 write-pending (not supported yet)
     clean, but writes are blocked waiting for 'active' to be written.

 active-idle
     like active, but no writes have been seen for a while (100msec).

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
NeilBrown 4254376914 [PATCH] md: Don't write dirty/clean update to spares - leave them alone
- record the 'event' count on each individual device (they
  might sometimes be slightly different now)
- add a new value for 'sb_dirty': '3' means that the super
  block only needs to be updated to record a clean<->dirty
  transition.
- Prefer odd event numbers for dirty states and even numbers
  for clean states
- Using all the above, don't update the superblock on
  a spare device if the update is just doing a clean-dirty
  transition.  To accomodate this, a transition from
  dirty back to clean might now decrement the events counter
  if nothing else has changed.

The net effect of this is that spare drives will not see any IO requests
during normal running of the array, so they can go to sleep if that is what
they want to do.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
NeilBrown 07d84d109d [PATCH] md: Allow re-add to work on array without bitmaps
When an array has a bitmap, a device can be removed and re-added and only
blocks changes since the removal (as recorded in the bitmap) will be resynced.

It should be possible to do a similar thing to arrays without bitmaps.  i.e.
if a device is removed and re-added and *no* changes have been made in the
interim, then the add should not require a resync.

This patch allows that option.  This means that when assembling an array one
device at a time (e.g.  during device discovery) the array can be enabled
read-only as soon as enough devices are available, but extra devices can still
be added without causing a resync.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
NeilBrown 3285edf152 [PATCH] md: Fix bug that stops raid5 resync from happening
As data_disks is *less* than raid_disks, the current test here is obviously
wrong.  And as the difference is already available in conf->max_degraded, it
makes much more sense to use that.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
akpm@osdl.org b3cc9ec76b [PATCH] md: Fix Kconfig error
RAID5 recently changed to RAID456

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
Justin Piszcz 4d2554d045 [PATCH] md: md Kconfig speeling feex
I was experimenting with Linux SW raid today and found a spelling error when
reading the help menus...  (and fly spell found more).

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
NeilBrown 8838832830 [PATCH] md: Calculate correct array size for raid10 in new offset mode
The size calculation made assumtion which the new offset mode didn't
follow.  This gets the size right in all cases.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:39 -07:00
NeilBrown ce25c31bdd [PATCH] md: Change md/bitmap file handling to use bmap to file blocks-fix
Fix problems with new bmap based access to bitmap files.

1/ When not using a file based bitmap, attach a NULL list of buffers
   to each page so the common free_buffer routine can cope.
2/ Use submit_bh to read as well as write, rather than vfs_read.
   This makes read and write more symetric.
3/ sync the file before reading, to ensure that the page cache has no
   dirty pages that might get written out later.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown d785a06a0b [PATCH] md/bitmap: change md/bitmap file handling to use bmap to file blocks
If md is asked to store a bitmap in a file, it tries to hold onto the page
cache pages for that file, manipulate them directly, and call a cocktail of
operations to write the file out.  I don't believe this is a supportable
approach.

This patch changes the approach to use the same approach as swap files.  i.e.
bmap is used to enumerate all the block address of parts of the file and we
write directly to those blocks of the device.

swapfile only uses parts of the file that provide a full pages at contiguous
addresses.  We don't have that luxury so we have to cope with pages that are
non-contiguous in storage.  To handle this we attach buffers to each page, and
store the addresses in those buffers.

With this approach the pagecache may contain data which is inconsistent with
what is on disk.  To alleviate the problems this can cause, md invalidates the
pagecache when releasing the file.  If the file is to be examined while the
array is active (a non-critical but occasionally useful function), O_DIRECT io
must be used.  And new version of mdadm will have support for this.

This approach simplifies a lot of code:
 - we no longer need to keep a list of pages which we need to wait for,
   as the b_endio function can keep track of how many outstanding
   writes there are.  This saves a mempool.
 - -EAGAIN returns from write_page are no longer possible (not sure if
    they ever were actually).

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown acc55e2201 [PATCH] md/bitmap: tidy up i_writecount handling in md/bitmap
md/bitmap modifies i_writecount of a bitmap file to make sure that no-one else
writes to it.  The reverting of the change is sometimes done twice, and there
is one error path where it is omitted.

This patch tidies that up.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown 0cdd02cabd [PATCH] md/bitmap: remove dead code from md/bitmap
bitmap_active is never called, and the BITMAP_ACTIVE flag is never users or
tested, so discard them both.

Also remove some out-of-date 'todo' comments.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown a647e4bc5c [PATCH] md/bitmap: remove unnecessary page reference manipulations from md/bitmap code
md/bitmap gets a collection of pages representing the bitmap when it
initialises the bitmap, and puts all the references when discarding the
bitmap.

It also occasionally takes extra references without any good reason, and
sometimes drops them ...  though it doesn't always drop them, which can result
in a memory leak.

This patch removes the unnecessary 'get_page' calls, and the corresponding
'put_page' calls.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown e16b68b6e4 [PATCH] md/bitmap: use set_bit etc for bitmap page attributes
In particular, this means that we use 4 bits per page instead of a whole
unsigned long.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown ec7a3197f4 [PATCH] md/bitmap: cleaner separation of page attribute handlers in md/bitmap
md/bitmap has some attributes per-page.  Handling of these attributes in
largely abstracted in set_page_attr and clear_page_attr.  However
get_page_attr exposes the format used to store them.  So prior to changing
that format, introduce test_page_attr instead of get_page_attr, and make
appropriate usage changes.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown 0b79ccf0cd [PATCH] md/bitmap: remove bitmap writeback daemon
md/bitmap currently has a separate thread to wait for writes to the bitmap
file to complete (as we cannot get a callback on that action).

However this isn't needed as bitmap_unplug is called from process context and
waits for the writeback thread to do it's work.  The same result can be
achieved by doing the waiting directly in bitmap_unplug.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown d7375ab324 [PATCH] md/bitmap: fix online removal of file-backed bitmaps
When "mdadm --grow /dev/mdX --bitmap=none" is used to remove a filebacked
bitmap, the bitmap was disconnected from the array, but the file wasn't closed
(until the array was stopped).

The file also wasn't closed if adding the bitmap file failed.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:38 -07:00
NeilBrown 52c03291a8 [PATCH] md: split reshape portion of raid5 sync_request into a separate function
... as raid5 sync_request is WAY too big.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:37 -07:00
Adrian Bunk 5e56341d02 [PATCH] md: make md_print_devices() static
This patch makes the needlessly global md_print_devices() static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:37 -07:00
NeilBrown c93983bf51 [PATCH] md: support stripe/offset mode in raid10
The "industry standard" DDF format allows for a stripe/offset layout where
data is duplicated on different stripes.  e.g.

  A  B  C  D
  D  A  B  C
  E  F  G  H
  H  E  F  G

(columns are drives, rows are stripes, LETTERS are chunks of data).

This is similar to raid10's 'far' mode, but not quite the same.  So enhance
'far' mode with a 'far/offset' option which follows the layout of DDFs
stripe/offset.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:37 -07:00
NeilBrown 7c7546ccf6 [PATCH] md: allow a linear array to have drives added while active
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:37 -07:00
NeilBrown 5fd6c1dce0 [PATCH] md: allow checkpoint of recovery with version-1 superblock
For a while we have had checkpointing of resync.  The version-1 superblock
allows recovery to be checkpointed as well, and this patch implements that.

Due to early carelessness we need to add a feature flag to signal that the
recovery_offset field is in use, otherwise older kernels would assume that a
partially recovered array is in fact fully recovered.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:37 -07:00
NeilBrown a8a55c387d [PATCH] md: remove nuisance message at shutdown
At shutdown, we switch all arrays to read-only, which creates a message for
every instantiated array, even those which aren't actually active.

So remove the message for non-active arrays.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:37 -07:00
NeilBrown 16a53ecc35 [PATCH] md: merge raid5 and raid6 code
There is a lot of commonality between raid5.c and raid6main.c.  This patches
merges both into one module called raid456.  This saves a lot of code, and
paves the way for online raid5->raid6 migrations.

There is still duplication, e.g.  between handle_stripe5 and handle_stripe6.
This will probably be cleaned up later.

Cc: "H. Peter Anvin" <hpa@zytor.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>
2006-06-26 09:58:37 -07:00
NeilBrown 16f17b39f3 [PATCH] md: increase the delay before marking metadata clean, and make it configurable
When a md array has been idle (no writes) for 20msecs it is marked as 'clean'.
 This delay turns out to be too short for some real workloads.  So increase it
to 200msec (the time to update the metadata should be a tiny fraction of that)
and make it sysfs-configurable.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:37 -07:00
NeilBrown 9443a1d1f7 [PATCH] md: remove useless ioctl warning
This warning was slightly useful back in 2.2 days, but is more an annoyance
now.  It makes it awkward to add new ioctls (that we we are likely to do that
in the current climate, but it is possible).

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
NeilBrown 8932c2e0dc [PATCH] md: remove arbitrary limit on chunk size
The largest chunk size the code can support without substantial surgery is
2^30 bytes, so make that the limit instead of an arbitrary 4Meg.  Some day,
the 'chunksize' should change to a sector-shift instead of a byte-count.  Then
no limit would be needed.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
NeilBrown c70810b327 [PATCH] md: reformat code in raid1_end_write_request to avoid goto
A recent change made this goto unnecessary, so reformat the code to make it
clearer what is 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>
2006-06-26 09:58:36 -07:00
Alasdair G Kergon 72d9486169 [PATCH] dm: improve error message consistency
Tidy device-mapper error messages to include context information
automatically.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
Alasdair G Kergon 5c6bd75d06 [PATCH] dm: prevent removal if open
If you misuse the device-mapper interface (or there's a bug in your userspace
tools) it's possible to end up with 'unlinked' mapped devices that cannot be
removed until you reboot (along with uninterruptible processes).

This patch prevents you from removing a device that is still open.

It introduces dm_lock_for_deletion() which is called when a device is about to
be removed to ensure that nothing has it open and nothing further can open it.
 It uses a private open_count for this which also lets us remove one of the
problematic bdget_disk() calls elsewhere.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
David Teigland c2ade42dd3 [PATCH] dm: create error table
Add a library function dm_create_error_table() to create a table that rejects
any I/O sent to a device with EIO.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
Alasdair G Kergon 17b2f66f2a [PATCH] dm: add exports
Move definitions of core device-mapper functions for manipulating mapped
devices and their tables to <linux/device-mapper.h> advertising their
availability for use elsewhere in the kernel.

Protect the contents of device-mapper.h with ifdef __KERNEL__.  And throw
in a few formatting clean-ups and extra comments.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
Alasdair G Kergon 2b06cfff12 [PATCH] dm: consolidate creation functions
Merge dm_create() and dm_create_with_minor() by introducing the special value
DM_ANY_MINOR to request the allocation of the next available minor number.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
David Teigland 814d68629b [PATCH] dm table split_args: handle no input
Return sense if dm_split_args is called with a NULL input parameter.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:36 -07:00
Jonathan Brassow ce503f59ae [PATCH] dm kcopyd: error accumulation fix
kcopyd should accumulate errors - otherwise I/O failures may be ignored
unintentionally.

And invert 'success' (used in a future patch), using a more intuitive
!(read_err || write_err).

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Alasdair G Kergon 8a835f11bc [PATCH] dm mirror log: sync_count fix
When a mirror is reduced in size, clear the part of the bitmap that is no
longer used.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Alasdair G Kergon 29121bd0b0 [PATCH] dm mirror log: bitset_size fix
Fix the 'sizeof' in the region log bitmap size calculation: it's uint32_t, not
unsigned long - this breaks on some archs.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Alasdair G Kergon b7cca195c4 [PATCH] dm mirror log: refactor context
Refactor the code that creates the core and disk log contexts to avoid the
repeated allocation of clean_bits introduced by the last patch.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Kevin Corry 702ca6f0be [PATCH] dm mirror log: sector size fix
On-disk logs for dm-mirror devices are currently hard-coded to use 512 byte
hard-sector-sizes.  This patch fixes dm-log so it will work with devices with
non-512-byte hard-sector-sizes.

To maintain full compatibility, instead of moving the clean-bits bitset to a
bitset, and enlarges the disk-header buffer to encompass both the header and
the bitset.  The I/O routines for the bitset are removed, and the I/O routines
for the disk-header now also read/write the bitset.

Signed-off-by: Kevin Corry <kevcorry@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Milan Broz 143535396c [PATCH] dm table: get_target: fix last index
The table is indexed from 0, so an index equal to t->num_targets should be
rejected.

(There is no code in the current tree that would exercise this bug.)

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Neil Brown e4c8b3ba34 [PATCH] dm: mirror sector offset fix
The device-mapper core does not perform any remapping of bios before passing
them to the targets.  If a particular mapping begins part-way into a device,
targets obtain the sector relative to the start of the mapping by subtracting
ti->begin.

The dm-raid1 target didn't do this everywhere: this patch fixes it, taking
care to subtract ti->begin exactly once for each bio.

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Jeff Mahoney f0b0411536 [PATCH] dm: fix block device initialisation
In alloc_dev(), we register the device with the block layer and then continue
to initialize the device.  But register_disk() makes the device available to
be opened before we have completed initialising it.

This patch moves the final bits of the initialization above the disk
registration.

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Jeff Mahoney 10da4f795f [PATCH] dm: add module ref counting
The reference counting on dm-mod is zero if no mapped devices are open.  This
is incorrect, and can lead to an oops if the module is unloaded while mapped
devices exist.

This patch claims a reference to the module whenever a device is created, and
drops it again when the device is freed.

Devices must be removed before dm-mod is unloaded.

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Jeff Mahoney 7ec75f2547 [PATCH] dm: fix mapped device ref counting
To avoid races, _minor_lock must be held while changing mapped device
reference counts.

There are a few paths where a mapped_device pointer is returned before a
reference is taken.  This patch fixes them.

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:35 -07:00
Jeff Mahoney fba9f90e56 [PATCH] dm: add DMF_FREEING
There is a chicken and egg problem between the block layer and dm in which the
gendisk associated with a mapping keeps a reference-less pointer to the
mapped_device.

This patch uses a new flag DMF_FREEING to indicate when the mapped_device is
no longer valid.  This is checked to prevent any attempt to open the device
from succeeding while the device is being destroyed.

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:34 -07:00
Jeff Mahoney f32c10b099 [PATCH] dm: change minor_lock to spinlock
While removing a device, another another thread might attempt to resurrect it.

This patch replaces the _minor_lock mutex with a spinlock and uses
atomic_dec_and_lock() to serialize reference counting in dm_put().

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:34 -07:00
Jeff Mahoney 62f75c2f32 [PATCH] dm: move idr_pre_get
idr_pre_get() can sleep while allocating memory.

The next patch will change _minor_lock into a spinlock, so this patch moves
idr_pre_get() outside the lock in preparation.

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:34 -07:00
Jeff Mahoney ba61fdd17d [PATCH] dm: fix idr minor allocation
One part of the system can attempt to use a mapped device before another has
finished initialising it or while it is being freed.

This patch introduces a place holder value, MINOR_ALLOCED, to mark the minor
as allocated but in a state where it can't be used, such as mid-allocation or
mid-free.  At the end of the initialization, it replaces the place holder with
the pointer to the mapped_device, making it available to the rest of the dm
subsystem.

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:34 -07:00
Alasdair G Kergon c51c275249 [PATCH] dm snapshot: unify chunk_size
Persistent snapshots currently store a private copy of the chunk size.
Userspace also supplies the chunk size when loading a snapshot.  Ensure
consistency by only storing the chunk_size in one place instead of two.

Currently the two sizes will differ if the chunk size supplied by userspace
does not match the chunk size an existing snapshot actually uses.  Amongst
other problems, this causes an incorrect 'percentage full' to be reported.

The patch ensures consistency by only storing the chunk_size in one place,
removing it from struct pstore.  Some initialisation is delayed until the
correct chunk_size is known.  If read_header() discovers that the wrong chunk
size was supplied, the 'area' buffer (which the header already got read into)
is reinitialised to the correct size.

[akpm: too late for 2.6.17 - suitable for 2.6.17.x after it has settled]

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:34 -07:00
Akinobu Mita 179e09172a [PATCH] drivers: use list_move()
This patch converts the combination of list_del(A) and list_add(A, B) to
list_move(A, B) under drivers/.

Acked-by: Corey Minyard <minyard@mvista.com>
Cc: Ben Collins <bcollins@debian.org>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Alasdair Kergon <dm-devel@redhat.com>
Cc: Gerd Knorr <kraxel@bytesex.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frank Pavlic <fpavlic@de.ibm.com>
Acked-by: Matthew Wilcox <matthew@wil.cx>
Cc: Andrew Vasquez <linux-driver@qlogic.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:18 -07:00
Adrian Bunk a5d6839b75 [PATCH] drivers/md/raid6algos.c: fix a NULL dereference
This patch fixes a NULL dereference spotted by the Coverity checker.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:08 -07:00
NeilBrown c331eb04b9 [PATCH] md: Fix badness in sysfs_notify caused by md_new_event
From: NeilBrown <neilb@suse.de>

If an error is reported by a drive in a RAID array (which is done via
bi_end_io - in interrupt context), we call md_error and md_new_event which
calls sysfs_notify.  However sysfs_notify grabs a mutex and so cannot be
called in interrupt context.

This patch just creates a variant of md_new_event which avoids the sysfs
call, and uses that.  A better fix for later is to arrange for the event to
be called from user-context.

Note: avoiding the sysfs call isn't a problem as an error will not, by
itself, modify the sync_action attribute.  (We do still need to
wake_up(&md_event_waiters) as an error by itself will modify /proc/mdstat).

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-31 16:27:11 -07:00
Neil Brown c71d48877e [PATCH] Unlock md devices when stopping them on reboot.
otherwise we get nasty messages about locks not being released.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-26 11:52:11 -07:00
NeilBrown 5c4c33318d [PATCH] md: fix possible oops when starting a raid0 array
This loop that sets up the hash_table has problems.

Careful examination will show that the last time through, everything but
the first line is pointless.  This is because all it does is change 'cur'
and 'size' and neither of these are used after the loop.  This should ring
warning bells...  That last time through the loop,

        size += conf->strip_zone[cur].size

can index off the end of the strip_zone array.  Depending on what it finds
there, it might exit the loop cleanly, or it might spin going further and
further beyond the array until it hits an unmapped address.

This patch rearranges the code so that the last, pointless, iteration of
the loop never happens.  i.e.  the one statement of the last loop that is
needed is moved the the end of the previous loop - or to before the loop
starts - and the loop counter starts from 1 instead of 0.

Cc: "Don Dupuis" <dondster@gmail.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>
2006-05-23 10:35:31 -07:00
NeilBrown 2adc7d47c4 [PATCH] md: Fix inverted test for 'repair' directive.
We should be able to write 'repair' to /sys/block/mdX/md/sync_action,
however due to and inverted test, that always given EINVAL.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-21 12:59:17 -07:00
NeilBrown 5e7dd2ab6b [PATCH] md: Fix 'rdev->nr_pending' count when retrying barrier requests
When retrying a failed BIO_RW_BARRIER request, we need to keep the reference
in ->nr_pending over the whole retry.  Currently, we only hold the reference
if the failed request is the *last* one to finish - which is silly, because it
would normally be the first to finish.

So move the rdev_dec_pending call up into the didn't-fail branch.  As the rdev
isn't used in the later code, calling rdev_dec_pending earlier doesn't hurt.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-01 18:17:42 -07:00
NeilBrown 62de608da0 [PATCH] md: Improve detection of lack of barrier support in raid1
Move the test for 'do barrier work' down a bit so that if the first write to a
raid1 is a BIO_RW_BARRIER write, the checking done by superblock writes will
cause the right thing to happen.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-01 18:17:42 -07:00
NeilBrown bea2771871 [PATCH] md: Change ENOTSUPP to EOPNOTSUPP
Because that is what you get if a BIO_RW_BARRIER isn't supported!

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-01 18:17:42 -07:00
NeilBrown e0a33270ed [PATCH] md: Fixed refcounting/locking when attempting read error correction in raid10
We need to hold a reference to rdevs while reading and writing to attempt to
correct read errors.  This reference must be taken under an rcu lock.

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-01 18:17:42 -07:00
NeilBrown df30d0f4ca [PATCH] md: Avoid oops when attempting to fix read errors on raid10
We should add to the counter for the rdev *after* checking if the rdev is
NULL!!!

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-01 18:17:42 -07:00
Ingo Molnar 5dc5cf7dd2 [PATCH] md: locking fix
- fix mddev_lock() usage bugs in md_attr_show() and md_attr_store().
  [they did not anticipate the possibility of getting a signal]

- remove mddev_lock_uninterruptible() [unused]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-20 07:54:04 -07:00
NeilBrown 4508a7a734 [PATCH] sysfs: Allow sysfs attribute files to be pollable
It works like this:
  Open the file
  Read all the contents.
  Call poll requesting POLLERR or POLLPRI (so select/exceptfds works)
  When poll returns,
     close the file and go to top of loop.
   or lseek to start of file and go back to the 'read'.

Events are signaled by an object manager calling
   sysfs_notify(kobj, dir, attr);

If the dir is non-NULL, it is used to find a subdirectory which
contains the attribute (presumably created by sysfs_create_group).

This has a cost of one int  per attribute, one wait_queuehead per kobject,
one int per open file.

The name "sysfs_notify" may be confused with the inotify
functionality.  Maybe it would be nice to support inotify for sysfs
attributes as well?

This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action
to be pollable

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-04-14 11:41:24 -07:00
NeilBrown 6f91fe88e4 [PATCH] md: make sure 64bit fields in version-1 metadata are 64-bit aligned
reshape_position is a 64bit field that was not 64bit aligned.  So swap with
new_level.

NOTE: this is a user-visible change.  However:
  - The bad code has not appeared in a released kernel
  - This code is still marked 'experimental'
  - This only affects version-1 superblock, which are not in wide use
  - These field are only used (rather than simply reported) by user-space
    tools in extemely rare circumstances : after a reshape crashes in the
    first second of the reshape process.

So I believe that, at this stage, the change is safe.  Especially if people
heed the 'help' message on use mdadm-2.4.1.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:30 -07:00
Eric Sesterhenn b638548384 BUG_ON() Conversion in md/raid10.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-02 13:34:29 +02:00
Eric Sesterhenn 43dab9bbe9 BUG_ON() Conversion in md/raid6main.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-02 13:33:30 +02:00
Eric Sesterhenn 78bafebd46 BUG_ON() Conversion in md/raid5.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-02 13:31:42 +02:00
Eric Sesterhenn 9e77c485f7 BUG_ON() Conversion in md/raid1.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:08:49 +02:00
Eric Sesterhenn 543cb2a451 BUG_ON() Conversion in md/dm-target.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:08:12 +02:00
NeilBrown ec350a7fc1 [PATCH] md: Raid-6 did not create sysfs entries for stripe cache
Signed-off-by: Brad Campbell <brad@wasp.net.au>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
NeilBrown 926ce2d8a7 [PATCH] md: Remove some code that can sleep from under a spinlock
And remove the comments that were put in inplace of a fix too....

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -08:00
NeilBrown 6b1117d505 [PATCH] md: Don't clear bits in bitmap when writing to one device fails during recovery
Currently a device failure during recovery leaves bits set in the bitmap.
This normally isn't a problem as the offending device will be rejected because
of errors.  However if device re-adding is being used with non-persistent
bitmaps, this can be a problem.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:19:01 -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
NeilBrown 4588b42e9d [PATCH] md: Update status_resync to handle LARGE devices
status_resync - used by /proc/mdstat to report the status of a resync, assumes
that device sizes will always fit into an 'unsigned long' This is no longer
the 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 1be7892fff [PATCH] md: Fix the 'failed' count for version-0 superblocks
We are counting failed devices twice, once of the device that is failed, and
once for the hole that has been left in the array.  Remove the former so
'failed' matches 'missing'.  Storing these counts in the superblock is a bit
silly anyway....

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 08:45:00 -08:00
NeilBrown c5a10f62c5 [PATCH] md: Add '4' to the list of levels for which bitmaps are supported
I really should make this a function of the personality....

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 08:45:00 -08:00
NeilBrown 89e5c8b5b8 [PATCH] md: Make sure QUEUE_FLAG_CLUSTER is set properly for md.
This flag should be set for a virtual device iff it is set for all underlying
devices.

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 08:45:00 -08:00
Kevin Corry a22c96c737 [PATCH] dm: remove unnecessary typecast
Signed-off-by: Kevin Corry <kevcorry@us.ibm.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:00 -08:00
Jun'ichi Nomura f165921df4 [PATCH] dm/md dependency tree in sysfs: dm to use bd_claim_by_disk
Use bd_claim_by_disk.

Following symlinks are created if dm-0 maps to sda:
  /sys/block/dm-0/slaves/sda --> /sys/block/sda
  /sys/block/sda/holders/dm-0 --> /sys/block/dm-0

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:00 -08:00
Jun'ichi Nomura 5463c7904c [PATCH] dm/md dependency tree in sysfs: md to use bd_claim_by_disk
Use bd_claim_by_disk.

Following symlinks are created if md0 is built from sda and sdb
  /sys/block/md0/slaves/sda --> /sys/block/sda
  /sys/block/md0/slaves/sdb --> /sys/block/sdb
  /sys/block/sda/holders/md0 --> /sys/block/md0
  /sys/block/sdb/holders/md0 --> /sys/block/md0

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:45:00 -08:00
Darrick J. Wong 3ac51e741a [PATCH] dm store geometry
Allow drive geometry to be stored with a new DM_DEV_SET_GEOMETRY ioctl.
Device-mapper will now respond to HDIO_GETGEO.  If the geometry information is
not available, zero will be returned for all of the parameters.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:59 -08:00
Mike Anderson 1134e5ae79 [PATCH] dm table: store md
Store an up-pointer to the owning struct mapped_device in every table when it
is created.

Access it with:
  struct mapped_device *dm_table_get_md(struct dm_table *t)

Tables linked to md must be destroyed before the md itself.

Signed-off-by: Mike Anderson <andmike@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:59 -08:00
Alasdair G Kergon 9ade92a9a5 [PATCH] dm: tidy mdptr
Change dm_get_mdptr() to take a struct mapped_device instead of dev_t.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:59 -08:00
Mike Anderson 7e51f257e8 [PATCH] dm: store md name
The patch stores a printable device number in struct mapped_device for use in
warning messages and with a proposed netlink interface.

Signed-off-by: Mike Anderson <andmike@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:59 -08:00
Jun'ichi Nomura 1ecac7fd74 [PATCH] dm flush queue EINTR
If dm_suspend() is cancelled, bios already added to the deferred list need to
be submitted.  Otherwise they remain 'in limbo' until there's a dm_resume().

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:59 -08:00
Alasdair G Kergon 138728dc96 [PATCH] dm snapshot: fix kcopyd destructor
Before removing a snapshot, wait for the completion of any kcopyd jobs using
it.

Do this by maintaining a count (nr_jobs) of how many outstanding jobs each
kcopyd_client has.

The snapshot destructor first unregisters the snapshot so that no new kcopyd
jobs (created by writes to the origin) will reference that particular
snapshot.  kcopyd_client_destroy() is now run next to wait for the completion
of any outstanding jobs before the snapshot exception structures (that those
jobs reference) are freed.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:59 -08:00
NeilBrown 969429b504 [PATCH] dm: make sure QUEUE_FLAG_CLUSTER is set properly
This flag should be set for a virtual device iff it is set for all
underlying devices.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:59 -08:00
Andrew Morton 4ee218cd67 [PATCH] dm: remove SECTOR_FORMAT
We don't know what type sector_t has.  Sometimes it's unsigned long, sometimes
it's unsigned long long.  For example on ppc64 it's unsigned long with
CONFIG_LBD=n and on x86_64 it's unsigned long long with CONFIG_LBD=n.

The way to handle all of this is to always use unsigned long long and to
always typecast the sector_t when printing it.

Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:58 -08:00
Jun'ichi Nomura 930d332a23 [PATCH] drivers/md/dm-raid1.c: Fix inconsistent mirroring after interrupted recovery
dm-mirror has potential data corruption problem: while on-disk log shows
that all disk contents are in-sync, actual contents of the disks are not
synchronized.  This problem occurs if initial recovery (synching) is
interrupted and resumed.

Attached patch fixes this problem.

Background:

rh_dec() changes the region state from RH_NOSYNC (out-of-sync) to RH_CLEAN
(in-sync), which results in the corresponding bit of clean_bits being set.

This is harmful if on-disk log is used and the map is removed/suspended
before the initial sync is completed.  The clean_bits is written down to
the on-disk log at the map removal, and, upon resume, it's read and copied
to sync_bits.  Since the recovery process refers to the sync_bits to find a
region to be recovered, the region whose state was changed from RH_NOSYNC
to RH_CLEAN is no longer recovered.

If you haven't applied dm-raid1-read-balancing.patch proposed in dm-devel
sometimes ago, the contents of the mirrored disk just corrupt silently.  If
you have, balanced read may get bogus data from out-of-sync disks.

The patch keeps RH_NOSYNC state unchanged.  It will be changed to
RH_RECOVERING when recovery starts and get reclaimed when the recovery
completes.  So it doesn't leak the region hash entry.

Description:

Keep RH_NOSYNC state unchanged when I/O on the region completes.

rh_dec() changes the region state from RH_NOSYNC (out-of-sync) to RH_CLEAN
(in-sync), which results in the corresponding bit of clean_bits being set.

This is harmful if on-disk log is used and the map is removed/suspended
before the initial sync is completed.  The clean_bits is written down to
the on-disk log at the map removal, and, upon resume, it's read and copied
to sync_bits.  Since the recovery process refers to the sync_bits to find a
region to be recovered, the region whose state was changed from RH_NOSYNC
to RH_CLEAN is no longer recovered.

If you haven't applied dm-raid1-read-balancing.patch proposed in dm-devel
sometimes ago, the contents of the mirrored disk just corrupt silently.  If
you have, balanced read may get bogus data from out-of-sync disks.

The RH_NOSYNC region will be changed to RH_RECOVERING when recovery starts
on the region and get reclaimed when the recovery completes.  So it doesn't
leak the region hash entry.

Alasdair said:

  I've analysed the relevant part of the state machine and I believe that
  the patch is correct.

  (Further work on this code is still needed - this patch has the
  side-effect of holding onto memory unnecessarily for long periods of time
  under certain workloads - but better that than corrupting data.)

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:58 -08:00
Alasdair G Kergon 76df1c651b [PATCH] device-mapper snapshot: fix invalidation
When a snapshot becomes invalid, s->valid is set to 0.  In this state, a
snapshot can no longer be accessed.

When s->lock is acquired, before doing anything else, s->valid must be checked
to ensure the snapshot remains valid.

This patch eliminates some races (that may cause panics) by adding some
missing checks.  At the same time, some unnecessary levels of indentation are
removed and snapshot invalidation is moved into a single function that always
generates a device-mapper event.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:58 -08:00
Alasdair G Kergon b4b610f684 [PATCH] device-mapper snapshot: replace sibling list
The siblings "list" is used unsafely at the moment.

Firstly, only the element on the list being changed gets locked (via the
snapshot lock), not the next and previous elements which have pointers that
are also being changed.

Secondly, if you have two or more snapshots and write to the same chunk a
second time before every snapshot has finished making its private copy of the
data, if you're unlucky, _origin_write() could attempt its list_merge() and
dereference a 'last' pointer to a pending_exception structure that has just
been freed.

Analysis reveals that the list is actually only there for reference counting.
If 5 pending_exceptions are needed in origin_write, then the 5 are joined
together into a 5-element list - without a separate list head because there's
nowhere suitable to store it.  As the pending_exceptions complete, they are
removed from the list one-by-one and any contents of origin_bios get moved
across to one of the remaining pending_exceptions on the list.  Whichever one
is last is detected because list_empty() is then true and the origin_bios get
submitted.

The fix proposed here uses an alternative reference counting mechanism by
choosing one of the pending_exceptions as primary and maintaining an atomic
counter there.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:58 -08:00
Alasdair G Kergon eccf081799 [PATCH] device-mapper snapshot: fix origin_write pending_exception submission
Say you have several snapshots of the same origin and then you issue a write
to some place in the origin for the first time.

Before the device-mapper snapshot target lets the write go through to the
underlying device, it needs to make a copy of the data that is about to be
overwritten.  Each snapshot is independent, so it makes one copy for each
snapshot.

__origin_write() loops through each snapshot and checks to see whether a copy
is needed for that snapshot.  (A copy is only needed the first time that data
changes.)

If a copy is needed, the code allocates a 'pending_exception' structure
holding the details.  It links these together for all the snapshots, then
works its way through this list and submits the copying requests to the kcopyd
thread by calling start_copy().  When each request is completed, the original
pending_exception structure gets freed in pending_complete().

If you're very unlucky, this structure can get freed *before* the submission
process has finished walking the list.

This patch:

  1) Creates a new temporary list pe_queue to hold the pending exception
     structures;

  2) Does all the bookkeeping up-front, then walks through the new list
     safely and calls start_copy() for each pending_exception that needed it;

  3) Avoids attempting to add pe->siblings to the list if it's already
     connected.

[NB This does not fix all the races in this code.  More patches will follow.]

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:58 -08:00
Linus Torvalds 9ae21d1bb3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  drivers/char/ftape/lowlevel/fdc-io.c: Correct a comment
  Kconfig help: MTD_JEDECPROBE already supports Intel
  Remove ugly debugging stuff
  do_mounts.c: Minor ROOT_DEV comment cleanup
  BUG_ON() Conversion in drivers/s390/block/dasd_devmap.c
  BUG_ON() Conversion in mm/mempool.c
  BUG_ON() Conversion in mm/memory.c
  BUG_ON() Conversion in kernel/fork.c
  BUG_ON() Conversion in ipc/sem.c
  BUG_ON() Conversion in fs/ext2/
  BUG_ON() Conversion in fs/hfs/
  BUG_ON() Conversion in fs/dcache.c
  BUG_ON() Conversion in fs/buffer.c
  BUG_ON() Conversion in input/serio/hp_sdc_mlc.c
  BUG_ON() Conversion in md/dm-table.c
  BUG_ON() Conversion in md/dm-path-selector.c
  BUG_ON() Conversion in drivers/isdn
  BUG_ON() Conversion in drivers/char
  BUG_ON() Conversion in drivers/mtd/
2006-03-26 09:41:18 -08:00
Matthew Dobson 93d2341c75 [PATCH] mempool: use mempool_create_slab_pool()
Modify well over a dozen mempool users to call mempool_create_slab_pool()
rather than calling mempool_create() with extra arguments, saving about 30
lines of code and increasing readability.

Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:00 -08:00
Matthew Dobson 26b6e051bc [PATCH] mempool: use common mempool kzalloc allocator
This patch changes a mempool user, which is basically just a wrapper around
kzalloc(), to use the common mempool_kmalloc/kfree, rather than its own
wrapper function, removing duplicated code.

Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:59 -08:00
Matthew Dobson 0eaae62aba [PATCH] mempool: use common mempool kmalloc allocator
This patch changes several mempool users, all of which are basically just
wrappers around kmalloc(), to use the common mempool_kmalloc/kfree, rather
than their own wrapper function, removing a bunch of duplicated code.

Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:59 -08:00
Matthew Dobson a19b27ce38 [PATCH] mempool: use common mempool page allocator
Convert two mempool users that currently use their own mempool-backed page
allocators to use the generic mempool page allocator.

Also included are 2 trivial whitespace fixes.

Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:59 -08:00
Ingo Molnar 14cc3e2b63 [PATCH] sem2mutex: misc static one-file mutexes
Semaphore to mutex conversion.

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

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jens Axboe <axboe@suse.de>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: Greg KH <greg@kroah.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:55 -08:00
Eric Sesterhenn 547bc92649 BUG_ON() Conversion in md/dm-table.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-26 18:22:50 +02:00
Eric Sesterhenn c163c7293e BUG_ON() Conversion in md/dm-path-selector.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-26 18:21:58 +02:00
Linus Torvalds 1e8c573933 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (21 commits)
  BUG_ON() Conversion in drivers/video/
  BUG_ON() Conversion in drivers/parisc/
  BUG_ON() Conversion in drivers/block/
  BUG_ON() Conversion in sound/sparc/cs4231.c
  BUG_ON() Conversion in drivers/s390/block/dasd.c
  BUG_ON() Conversion in lib/swiotlb.c
  BUG_ON() Conversion in kernel/cpu.c
  BUG_ON() Conversion in ipc/msg.c
  BUG_ON() Conversion in block/elevator.c
  BUG_ON() Conversion in fs/coda/
  BUG_ON() Conversion in fs/binfmt_elf_fdpic.c
  BUG_ON() Conversion in input/serio/hil_mlc.c
  BUG_ON() Conversion in md/dm-hw-handler.c
  BUG_ON() Conversion in md/bitmap.c
  The comment describing how MS_ASYNC works in msync.c is confusing
  rcu: undeclared variable used in documentation
  fix typos "wich" -> "which"
  typo patch for fs/ufs/super.c
  Fix simple typos
  tabify drivers/char/Makefile
  ...
2006-03-25 08:41:09 -08:00
Adrian Bunk 7e31765550 [PATCH] md/bitmap.c:bitmap_mask_state(): fix inconsequent NULL checking
We dereference bitmap both one line above and one line below this check
rendering this check quite useless.

Spotted by the Coverity checker.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:57 -08:00
Eric Sesterhenn 4401d13899 BUG_ON() Conversion in md/dm-hw-handler.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-24 18:36:27 +01:00
Eric Sesterhenn 5daf2cf19a BUG_ON() Conversion in md/bitmap.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-24 18:35:26 +01:00
Jens Axboe 2056a782f8 [PATCH] Block queue IO tracing support (blktrace) as of 2006-03-23
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-23 20:00:26 +01:00
Alasdair G Kergon d2044a94e8 [PATCH] dm: bio split bvec fix
The code that handles bios that span table target boundaries by breaking
them up into smaller bios will not split an individual struct bio_vec into
more than two pieces.  Sometimes more than that are required.

This patch adds a loop to break the second piece up into as many pieces as
are necessary.

Cc: "Abhishek Gupta" <abhishekgupt@gmail.com>
Cc: Dan Smith <danms@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:55 -08:00
Al Viro 1312f40e11 [PATCH] regularize blk_cleanup_queue() use
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-03-18 18:34:20 -05:00
Kevin Corry 8ba32fde2c [PATCH] dm stripe: Fix bounds
The dm-stripe target currently does not enforce that the size of a stripe
device be a multiple of the chunk-size.  Under certain conditions, this can
lead to I/O requests going off the end of an underlying device.  This
test-case shows one example.

echo "0 100 linear /dev/hdb1 0" | dmsetup create linear0
echo "0 100 linear /dev/hdb1 100" | dmsetup create linear1
echo "0 200 striped 2 32 /dev/mapper/linear0 0 /dev/mapper/linear1 0" | \
   dmsetup create stripe0
dd if=/dev/zero of=/dev/mapper/stripe0 bs=1k

This will produce the output:
dd: writing '/dev/mapper/stripe0': Input/output error
97+0 records in
96+0 records out

And in the kernel log will be:
attempt to access beyond end of device
dm-0: rw=0, want=104, limit=100

The patch will check that the table size is a multiple of the stripe
chunk-size when the table is created, which will prevent the above striped
device from being created.

This should not affect tools like LVM or EVMS, since in all the cases I can
think of, striped devices are always created with the sizes being a
multiple of the chunk-size.

The size of a stripe device must be a multiple of its chunk-size.

(akpm: that typecast is quite gratuitous)

Signed-off-by: Kevin Corry <kevcorry@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-17 07:51:25 -08:00
NeilBrown 04b857f74c [PATCH] md: Fix several raid1 bugs which cause a memory leak
- wrong test for 'is this a BARRIER bio'
- not freeing on all possible paths.
- using r1_bio after freeing 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>
2006-03-09 19:47:37 -08:00
Jun'ichi Nomura 63d94e482d [PATCH] dm: free minor after unlink gendisk
Minor number should be freed after del_gendisk().  Otherwise, there could
be a window where 2 registered gendisk has same minor number.

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-24 14:31:39 -08:00
Jun'ichi Nomura d9dde59ba0 [PATCH] dm: missing bdput/thaw_bdev at removal
Need to unfreeze and release bdev otherwise the bdev inode with
inconsistent state is reused later and cause problem.

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-24 14:31:39 -08:00
NeilBrown 8ed75463b9 [PATCH] md: Make sure rdev->size gets set for version-1 superblocks
Sometimes it doesn't so make the code more like the version-0 code which
works.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:32:00 -08:00
NeilBrown 29fc7e3e70 [PATCH] md: Assorted little md fixes
- version-1 superblock
  + The default_bitmap_offset is in sectors, not bytes.
  + the 'size' field in the superblock is in sectors, not KB
- raid0_run should return a negative number on error, not '1'
- raid10_read_balance should not return a valid 'disk' number if
     ->rdev turned out to be NULL
- kmem_cache_destroy doesn't like being passed a NULL.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:32:00 -08:00
NeilBrown 284ae7cab0 [PATCH] md: Handle overflow of mdu_array_info_t->size better
mdu_array_info_t->size is 'int', which isn't big enough for the size (in KB of
each component in) some arrays.

So rather than a random overflow, set size to -1 when it cannot be set
correctly.

To update aspect on an array, userspace will sometimes:
  get_array_info
  change one field
  set_array_info

in this case, we don't want the '-1' in 'size' to change to size, or look like
a size change at all.  So test for that in update_array_info.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:31:59 -08:00
Stefan Bader 1113a7e92e [PATCH] device-mapper log bitset: fix big endian find_next_zero_bit
This is a fix to the device-mapper-log-bitset-fix-endian patch that
switched to ext2_* versions of the set and clear bit functions.  The
find_next_zero_bit function also has to be the ext2 one.  Otherwise the
mirror target tries to recover non-existent regions beyond the end of
device.

Signed-off-by: Stefan Bader <shbader@de.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-02 15:07:13 -08:00
NeilBrown 35849c75d7 [PATCH] md: Add sysfs access to raid6 stripe cache size
.. just as we already have for raid5.

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-02 15:07:12 -08:00
NeilBrown 978f946bb6 [PATCH] md: Don't remove bitmap from md array when switching to read-only
While a read-only array doesn't not really need a bitmap, we should
not remove the bitmap when switching an array to read-only because
 a/ There is no code to re-add the bitmap which switching to read-write,
 b/ There is insufficient locking - the bitmap could be accessed while it is
    being removed.

Cc: Reuben Farrelly <reuben-lkml@reub.net>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-02 15:07:12 -08:00
NeilBrown f0ca340cd2 [PATCH] md: Make sure array geometry changes persist with version-1 superblocks
super_1_sync only updates fields in the superblock that might have changed.

'raid_disks' and 'size' could have changed, but this information doesn't get
updated....  until this patch.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-02 15:07:11 -08:00
NeilBrown 6d89332b77 [PATCH] md: Fix device-size updates in md
As 'array_size' is a 'sector_t', it may overflow inappropriately when shifted
10 bits.  So We should cast it to a loff_t first.

There are two places with this problem, but the second (in update_raid_disks)
isn't needed so just remove it:
  The only personality that handles ->reshape currently is raid1,
  and it doesn't change the size of the array.
  When added for raid5/6, reshape again won't change the size of the array,
  at least not straight away.
  This code might be need for reshaping 'linear' but linear->shape,
  if implemented, should probably do the i_size_write itself.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-02 15:07:10 -08:00
Alasdair G Kergon 3ee247ebce [PATCH] dm: dm-table warning fix
drivers/md/dm-table.c:500: warning: comparison of distinct pointer types lacks a cast

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:11 -08:00
Alasdair G Kergon 4aac0a63fe [PATCH] device-mapper snapshot: barriers not supported
The snapshot and origin targets are incapable of handling barriers and need to
indicate this.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:11 -08:00
Jun'ichi "Nick" Nomura 3eaf840e0b [PATCH] device-mapper disk statistics: timing
Record I/O timing statistics

The start time is added to struct dm_io, an existing structure allocated
privately internally within dm and attached to each incoming bio.

We export disk_round_stats() from block/ll_rw_blk.c instead of creating a
private clone.

Signed-off-by: Jun'ichi "Nick" Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:11 -08:00
Kevin Corry 12f03a49cf [PATCH] device-mapper statistics: basic
Record basic I/O statistics for mapped devices.

Signed-off-by: Kevin Corry <kevcorry@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:10 -08:00
Alasdair G Kergon dab6a42915 [PATCH] device-mapper ioctl: reduce PF_MEMALLOC usage
Reduce substantially the amount of code using PF_MEMALLOC, as envisaged in the
original FIXME.

If you're using lvm2, for this patch to work correctly you should update to
lvm2 version 2.02.01 or later and device-mapper version 1.02.02 or later.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:10 -08:00
Patrick Caulfield a4fc4717fc [PATCH] device-mapper log bitset: fix endian
Clean up the code responsible for the on-disk mirror logs by using the
set_le_bit test_le_bit functions of ext2.  That makes the BE machines keep the
bitmap internally in LE order - it does mean you can't use any other type of
operations on the bitmap words but that looks to be OK in this instance.  The
efficiency tradeoff is very minimal as you would expect for something that
ext2 uses.

This allows us to remove bits_to_core(), bits_to_disk() and log->disk_bits.

Also increment the mirror log disk version transparently to avoid sharing with
older kernels that suffered from the 64-bit BE bug.

Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:10 -08:00
Alasdair G Kergon aa14edeb99 [PATCH] device-mapper snapshot: load metadata on creation
Move snapshot metadata loading to happen when the table is created instead of
when the device is resumed.  Writes to the origin device don't trigger
exceptions until each snapshot table becomes active when resume() is called on
each snapshot.

If you're using lvm2, for this patch to work properly you should update to
lvm2 version 2.02.01 or later and device-mapper version 1.02.02 or later.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:10 -08:00
Alan Cox 715b49ef2d [PATCH] EDAC: atomic scrub operations
EDAC requires a way to scrub memory if an ECC error is found and the chipset
does not do the work automatically.  That means rewriting memory locations
atomically with respect to all CPUs _and_ bus masters.  That means we can't
use atomic_add(foo, 0) as it gets optimised for non-SMP

This adds a function to include/asm-foo/atomic.h for the platforms currently
supported which implements a scrub of a mapped block.

It also adjusts a few other files include order where atomic.h is included
before types.h as this now causes an error as atomic_scrub uses u32.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:30 -08:00
NeilBrown 17115e0388 [PATCH] md: Clear clevel whenever level is set.
The 'level' of an md array can be set as either a number of a string.  When
one is set, the other must be marked 'undefined'.  This wasn't being done
in one place: where new arrays are created.

Result: if md1 is a raid1, it is stopped and a raid5 is created there, it
might still appear to be a raid1.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 23:15:32 -08:00
Arjan van de Ven 858119e159 [PATCH] Unlinline a bunch of other functions
Remove the "inline" keyword from a bunch of big functions in the kernel with
the goal of shrinking it by 30kb to 40kb

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:06 -08:00
Neil Brown 1edf80d347 [PATCH] md: remove slashes from disk names when creation dev names in sysfs
e.g. The sx8 driver uses names like sx8/0.

This would make a md component dev name like

   /sys/block/md0/md/dev-sx8/0

which is not allowed.  So we change the '/' to '!' just like
fs/partitions/check.c(register_disk) does.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:49 -08:00
Jens Axboe daef265f15 [PATCH] dm: don't enable bouncing by default
DM doesn't need to bounce bio's on its own, but the block layer defaults
to that in blk_queue_make_request(). The lower level drivers should
bounce ios themselves, that is what they need to do if not layered below
dm anyways.

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:37:08 -08:00
Jesper Juhl 352d768b19 [PATCH] Decrease number of pointer derefs in multipath.c
Decrease the number of pointer derefs in drivers/md/multipath.c

Benefits of the patch:
 - Fewer pointer dereferences should make the code slightly faster.
 - Size of generated code is smaller
 - improved readability

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Alasdair G Kergon <agk@redhat.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:02:01 -08:00
Jes Sorensen 1b1dcc1b57 [PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-09 15:59:24 -08:00
Andrew Morton a136564702 [PATCH] remove gcc-2 checks
Remove various things which were checking for gcc-1.x and gcc-2.x compilers.

From: Adrian Bunk <bunk@stusta.de>

    Some documentation updates and removes some code paths for gcc < 3.2.

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:02 -08:00
Christoph Hellwig a885c8c431 [PATCH] Add block_device_operations.getgeo block device method
HDIO_GETGEO is implemented in most block drivers, and all of them have to
duplicate the code to copy the structure to userspace, as well as getting
the start sector.  This patch moves that to common code [1] and adds a
->getgeo method to fill out the raw kernel hd_geometry structure.  For many
drivers this means ->ioctl can go away now.

[1] the s390 block drivers are odd in this respect.  xpram sets ->start
    to 4 always which seems more than odd, and the dasd driver shifts
    the start offset around, probably because of it's non-standard
    sector size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@suse.de>
Cc: <mike.miller@hp.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:54 -08:00
NeilBrown 88202a0c84 [PATCH] md: allow sync-speed to be controlled per-device
Also export current (average) speed and status in sysfs.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:10 -08:00
NeilBrown 6d7ff7380b [PATCH] md: support adding new devices to md arrays via sysfs
Writing major:minor to md/new_dev will bind that device to the array.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:10 -08:00
NeilBrown 83303b613d [PATCH] md: allow available size of component devices to be set via sysfs
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:10 -08:00
Andrew Morton 6961ece46c [PATCH] md-export-rdev-data_offset-via-sysfs-fix
drivers/md/md.c: In function `offset_show':
drivers/md/md.c:1670: warning: long long unsigned int format, different type arg (arg 3)

Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:10 -08:00
NeilBrown 93c8cad03f [PATCH] md: export rdev->data_offset via sysfs
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:09 -08:00
NeilBrown 014236d2b8 [PATCH] md: expose device slot information via sysfs
This the role that a device has in an array can be viewed and set.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:09 -08:00
NeilBrown 2bf071bf50 [PATCH] md: keep better track of dev/array size when assembling md arrays
Move the checks - that dev size is never less than array size - into
bind_rdev_to_array to make sure it always happens properly (there is one place
where currently it doesn't).

Also reject any superblock which claims an array size smaller than the device
in question can hold.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:09 -08:00
NeilBrown da943b9912 [PATCH] md: allow md/raid_disks to be settable
If array is active, try to reshape, else just set the value.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:09 -08:00
NeilBrown 4dbcdc751c [PATCH] md: count corrected read errors per drive
Store this total in superblock (As appropriate), and make it available to
userspace via sysfs.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:09 -08:00
NeilBrown d9d166c2a9 [PATCH] md: allow array level to be set textually via sysfs
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:09 -08:00
NeilBrown 8bb93aaca2 [PATCH] md: expose md metadata format in sysfs
Allow it to be set to a particular version, or 'none'.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:08 -08:00
NeilBrown a35b0d695d [PATCH] md: allow md array component size to be accessed and set via sysfs
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:08 -08:00
NeilBrown 3b34380ae8 [PATCH] md: allow chunk_size to be settable through sysfs
... only before array is started of course.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:08 -08:00
NeilBrown 03c902e17f [PATCH] md: fix rdev->pending counts in raid1
When we do a user-requested check/repair, we lose count of the outstanding
requests...

Also make sure that when anything is written to md/sync_action, the
RECOVERY_NEEDED flag is set and the thread is woken up so any changes take
effect.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:08 -08:00
NeilBrown c708443c00 [PATCH] md: make sure bitmap updates are visible through filesystem
When we update a page_cache page in the kernel, we need to flush_dache_page or
userspace might not see the change.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:08 -08:00
Adrian Bunk 07dbd37727 [PATCH] drivers/md/md.c: make md_new_event() static
Make the needlessly global function md_new_event() static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:07 -08:00
NeilBrown 2989ddbd6e [PATCH] md: make a couple of names in md.c static
.. because they aren't used outside md.c

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:07 -08:00
NeilBrown f188593ee7 [PATCH] md: fix typo in comment
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:07 -08:00
NeilBrown bce74dac08 [PATCH] md: helper function to match commands written to sysfs files
Commands written to sysfs files may, or my not, be \n terminated.  We want to
accept with case.  For this we use cmd_match.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:07 -08:00
NeilBrown 1345b1d8ad [PATCH] md: define and use safe_put_page for md
md sometimes call put_page on NULL pointers (treating it like kfree).  This is
not safe, so define and use a 'safe_put_page' which checks for NULL.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:07 -08:00
NeilBrown 7dd5d34c6c [PATCH] md: remove inappropriate limits in md/bitmap configuration.
The kernel should not be imposing these policy limits: The time between
bitmap updates should certainly be allowed to be more than 15 seconds, and
if someone wants a bitmap chunk size in excess of 4MB, the kernel isn't the
place to stop them.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:07 -08:00
NeilBrown 097426f689 [PATCH] md: fix possible problem in raid1/raid10 error overwriting
The code to overwrite/reread for addressing read errors in raid1/raid10
currently assumes that the read will not alter the buffer which could be used
to write to the next device.  This is not a safe assumption to make.

So we split the loops into a overwrite loop and a separate re-read loop, so
that the writing is complete before reading is attempted.

Cc: Paul Clements <paul.clements@steeleye.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>
2006-01-06 08:34:06 -08:00
NeilBrown 2604b703b6 [PATCH] md: remove personality numbering from md
md supports multiple different RAID level, each being implemented by a
'personality' (which is often in a separate module).

These personalities have fairly artificial 'numbers'.  The numbers
are use to:
 1- provide an index into an array where the various personalities
    are recorded
 2- identify the module (via an alias) which implements are particular
    personality.

Neither of these uses really justify the existence of personality numbers.
The array can be replaced by a linked list which is searched (array lookup
only happens very rarely).  Module identification can be done using an alias
based on level rather than 'personality' number.

The current 'raid5' modules support two level (4 and 5) but only one
personality.  This slight awkwardness (which was handled in the mapping from
level to personality) can be better handled by allowing raid5 to register 2
personalities.

With this change in place, the core md module does not need to have an
exhaustive list of all possible personalities, so other personalities can be
added independently.

This patch also moves the check for chunksize being non-zero into the ->run
routines for the personalities that need it, rather than having it in core-md.
 This has a side effect of allowing 'faulty' and 'linear' not to have a
chunk-size set.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:06 -08:00
NeilBrown a24a8dd858 [PATCH] md: break out of a loop that doesn't need to run to completion
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:06 -08:00
NeilBrown a8745db232 [PATCH] md: convert recently exported symbol to GPL
...because that seems to be the preferred practice these days.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:06 -08:00
NeilBrown ea03aff93b [PATCH] md: convert various kmap calls to kmap_atomic
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:06 -08:00
NeilBrown fccddba060 [PATCH] md: tidy up raid5/6 hash table code
- replace open-coded hash chain with hlist macros

- Fix hash-table size at one page - it is already quite generous, so there
  will never be a need to use multiple pages, so no need for __get_free_pages

No functional change.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:06 -08:00
NeilBrown 9ffae0cf3e [PATCH] md: convert md to use kzalloc throughout
Replace multiple kmalloc/memset pairs with kzalloc calls.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:05 -08:00
NeilBrown 2d1f3b5d1b [PATCH] md: clean up 'page' related names in md
Substitute:

  page_cache_get -> get_page
  page_cache_release -> put_page
  PAGE_CACHE_SHIFT -> PAGE_SHIFT
  PAGE_CACHE_SIZE -> PAGE_SIZE
  PAGE_CACHE_MASK -> PAGE_MASK
  __free_page -> put_page

because we aren't using the page cache, we are just using pages.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:05 -08:00
NeilBrown d7603b7e3a [PATCH] md: make /proc/mdstat pollable
With this patch it is possible to poll /proc/mdstat to detect arrays appearing
or disappearing, to detect failures, recovery starting, recovery completing,
and devices being added and removed.

It is similar to the poll-ability of /proc/mounts, though different in that:

We always report that the file is readable (because face it, it is, even if
only for EOF).

We report POLLPRI when there is a change so that select() can detect
it as an exceptional event.  Not only are these exceptional events, but
that is the mechanism that the current 'mdadm' uses to watch for events
(It also polls after a timeout).
(We also report POLLERR like /proc/mounts).

Finally, we only reset the per-file event counter when the start of the file
is read, rather than when poll() returns an event.  This is more robust as it
means that an fd will continue to report activity to poll/select until the
program clearly responds to that activity.

md_new_event takes an 'mddev' which isn't currently used, but it will be soon.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:05 -08:00
NeilBrown 0eb3ff12aa [PATCH] md: raid10 read-error handling - resync and read-only
Add in correct read-error handling for resync and read-only situations.

When read-only, we don't over-write, so we need to mark the failed drive in
the r10_bio so we don't re-try it.  During resync, we always read all blocks,
so if there is a read error, we simply over-write it with the good block that
we found (assuming we found one).

Note that the recovery case still isn't handled in an interesting way.  There
is nothing useful to do for the 2-copies case.  If there are 3 or more copies,
then we could try reading from one of the non-missing copies, but this is a
bit complicated and very rarely would be used, so I'm leaving it for now.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:05 -08:00
NeilBrown 4443ae10ca [PATCH] md: auto-correct correctable read errors in raid10
Largely just a cross-port from raid1.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:05 -08:00
NeilBrown 220946c901 [PATCH] md: make sure read error on last working drive of raid1 actually returns failure
We are inadvertently setting the R1BIO_Uptodate bit on read errors when we
decide not to try correcting (because there are no other working devices).
This means that the read error is reported to the client as success.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:04 -08:00
NeilBrown d11c171e63 [PATCH] md: allow raid1 to check consistency
Where performing a user-requested 'check' or 'repair', we read all readable
devices, and compare the contents.  We only write to blocks which had read
errors, or blocks with content that differs from the first good device found.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:04 -08:00
NeilBrown 18f08819f4 [PATCH] md: support check-without-repair of raid10 arrays
Also keep count on the number of errors found.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:04 -08:00
NeilBrown 9910f16af3 [PATCH] md: fix up some rdev rcu locking in raid5/6
There is this "FIXME" comment with a typo in it!!  that been annoying me for
days, so I just had to remove it.

conf->disks[i].rdev should only be accessed if
  - we know we hold a reference or
  - the mddev->reconfig_sem is down or
  - we have a rcu_readlock

handle_stripe was referencing rdev in three places without any of these.  For
the first two, get an rcu_readlock.  For the last, the same access
(md_sync_acct call) is made a little later after the rdev has been claimed
under and rcu_readlock, if R5_Syncio is set.  So just use that access...
However R5_Syncio isn't really needed as the 'syncing' variable contains the
same information.  So use that instead.

Issues, comment, and fix are identical in raid5 and raid6.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:04 -08:00
NeilBrown cf30a473a0 [PATCH] md: handle errors when read-only
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:04 -08:00
NeilBrown 69382e8537 [PATCH] md: better handling for read error in raid1 during resync
Handling of read errors during resync is separate from handling of read errors
during normal IO in raid1.  A previous patch added support for read errors
during normal IO.  This one adds support for read errors during resync or
recovery.

The key differences are that we don't need to freeze the array, because the
normal handling of resync means that this part of the array will be idle
except for resync, and the read/overwrite/re-read is needed in a separate
piece of code.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:04 -08:00
NeilBrown 3e198f7826 [PATCH] md: tidyup some issues with raid1 resync and prepare for catching read errors
We are dereferencing ->rdev without an rcu lock!

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:03 -08:00
NeilBrown ddaf22abaa [PATCH] md: attempt to auto-correct read errors in raid1
On a read-error we suspend the array, then synchronously read the block from
other arrays until we find one where we can read it.  Then we try writing the
good data back everywhere and make sure it works.  If any write or subsequent
read fails, only then do we fail the device out of the array.

To be able to suspend the array, we need to also keep track of how many
requests are queued for handling by raid1d.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:03 -08:00
NeilBrown d69762e984 [PATCH] md: improve handing of read errors with raid6
This is a simple port of match functionality across from raid5.  If we get a
read error, we don't kick the drive straight away, but try to over-write with
good data first.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:03 -08:00
NeilBrown ca65b73bd9 [PATCH] md: fix raid6 resync check/repair code
raid6 currently does not check the P/Q syndromes when doing a resync, it just
calculates the correct value and writes it.  Doing the check can reduce writes
(often to 0) for a resync, and it is needed to properly implement the

  echo check > sync_action

operation.

This patch implements the appropriate checks and tidies up some related code.

It also allows raid6 user-requested resync to bypass the intent bitmap.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:03 -08:00
NeilBrown 6cce3b23f6 [PATCH] md: write intent bitmap support for raid10
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:03 -08:00
NeilBrown b15c2e57f0 [PATCH] md: move bitmap_create to after md array has been initialised
This is important because bitmap_create uses
  mddev->resync_max_sectors
and that doesn't have a valid value until after the array
has been initialised (with pers->run()).
[It doesn't make a difference for current personalities that
 support bitmaps, but will make a difference for raid10]

This has the added advantage of meaning with can move the thread->timeout
manipulation inside the bitmap.c code instead of sprinkling identical code
throughout all personalities.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:03 -08:00
NeilBrown 6ff8d8ec06 [PATCH] md: allow dirty raid[456] arrays to be started at boot
See patch to md.txt for more details

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:02 -08:00
NeilBrown 14f8d26b8e [PATCH] md: small cleanups for raid5
Resync code:
  A test that isn't needed,
  a 'compute_block' that makes more sense
    elsewhere (And then doesn't need a test),
  a couple of BUG_ONs to confirm the change makes sense.

Printks:
  A few were missing KERN_*

Also fix a typo in a comment..

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:34:02 -08:00
NeilBrown 0a27ec96b6 [PATCH] md: improve raid10 "IO Barrier" concept
raid10 needs to put up a barrier to new requests while it does resync or other
background recovery.  The code for this is currently open-coded, slighty
obscure by its use of two waitqueues, and not documented.

This patch gathers all the related code into 4 functions, and includes a
comment which (hopefully) explains what is 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>
2006-01-06 08:34:02 -08:00
NeilBrown 17999be4aa [PATCH] md: improve raid1 "IO Barrier" concept
raid1 needs to put up a barrier to new requests while it does resync or other
background recovery.  The code for this is currently open-coded, slighty
obscure by its use of two waitqueues, and not documented.

This patch gathers all the related code into 4 functions, and includes a
comment which (hopefully) explains what is 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>
2006-01-06 08:34:01 -08:00