This shouldn't be a BUG.  We should cope.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

If you try to assemble an array with too many missing devices, raid10 will now
reject the attempt, instead of allowing it.

Also check when hot-adding a drive and refuse the hot-add if the array is
beyond hope.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

There was another case where sb_size wasn't being set, so instead do the
sensible thing and set if when filling in the content of a superblock.  That
ensures that whenever we write a superblock, the sb_size MUST be set.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

[PATCH] md: make sure the new 'sb_size' is set properly device added without pre-existing superblock.

There are two ways to add devices to an md/raid array.

  It can have superblock written to it, and then given to the md driver,
  which will read the superblock (the new way)

or

  md can be told (through SET_ARRAY_INFO) the shape of the array, and
  the told about individual drives, and md will create the required
  superblock (the old way).

The newly introduced sb_size was only set for drives being added the
new way, not the old ways.  Oops :-(
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Just like failed drives have (F), so spare drives now have (S).
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Leave it unchanged if the original (0.90) is used, incase it might be a
compatability problem.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Doh.  I want the physical hard-sector-size, not the current block size...
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

On reflection, a better default location for hot-adding bitmaps with version-1
superblocks is immediately after the superblock.  There might not be much room
there, but there is usually atleast 3k, and that is a good start.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The bitmap code used to have two daemons, so there is some 'common' start/stop
code.  But now there is only one, so the common code is just noise.

This patch tidies this up somewhat.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

mddev->bitmap gets clearred before the writeback daemon is stopped.  So the
write_back daemon needs to be careful not to dereference the 'bitmap' if it is
NULL.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Switch MD to use the kthread infrastructure, to simplify the code and get rid
of tasklist_lock abuse in md_unregister_thread.

Also don't flush signals in md_thread, as the called thread will always do
that.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This is a direct port of the raid5 patch.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Most awkward part of this is delaying write requests until bitmap updates have
been flushed.

To achieve this, we have a sequence number (seq_flush) which is incremented
each time the raid5 is unplugged.

If the raid thread notices that this has changed, it flushes bitmap changes,
and assigned the value of seq_flush to seq_write.

When a write request arrives, it is given the number from seq_write, and that
write request may not complete until seq_flush is larger than the saved seq
number.

We have a new queue for storing stripes which are waiting for a bitmap flush
and an extra flag for stripes to record if the write was 'degraded' and so
should not clear the a bit in the bitmap.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

version-1 superblocks are not (normally) 4K long, and can be of variable size.
 Writing the full 4K can cause corruption (but only in non-default
configurations).

With this patch the super-block-flavour can choose a size to read, and set a
size to write based on what it finds.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

These inlines haven't been used for ages, they should go.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

read_sb_page() assumed that if sync_page_io fails, the device would be marked
faultly.  However it isn't.  So in the face of error, read_sb_page would loop
forever.

Redo the logic so that this cannot happen.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

As this is used to flag an internal bitmap.

Also, introduce symbolic names for feature bits.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It is possibly (and occasionally useful) to have a raid1 without persistent
superblocks.  The code in add_new_disk for adding a device to such an array
always tries to read a superblock.

This will obviously fail.

So do the appropriate test and call md_import_device with
appropriate args.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When hot-adding a bitmap, bitmap_daemon_work could get called while the bitmap
is being created, so don't set mddev->bitmap until the bitmap is ready.

This requires freeing the bitmap inside bitmap_create if creation failed
part-way through.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The 'lastrun' time wasn't being initialised, so it could be half a
jiffie-cycle before it seemed to be time to do work again.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

A state of 0 mean 'not quiesced'
A state of 1 means 'is quiesced'

The original code got this wrong.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

linear currently uses division by the size of the smallest componenet device
to find which device a request goes to.  If that smallest device is larger
than 2 terabytes, then the division will not work on some systems.

So we introduce a pre-shift, and take care not to make the hash table too
large, much like the code in raid0.

Also get rid of conf->nr_zones, which is not needed.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

If a device is flagged 'WriteMostly' and the array has a bitmap, and the
bitmap superblock indicates that write_behind is allowed, then write_behind is
enabled for WriteMostly devices.

Write requests will be acknowledges as complete to the caller (via b_end_io)
when all non-WriteMostly devices have completed the write, but will not be
cleared from the bitmap until all devices complete.

This requires memory allocation to make a local copy of the data being
written.  If there is insufficient memory, then we fall-back on normal write
semantics.
Signed-Off-By: NPaul Clements <paul.clements@steeleye.com>
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This allows a device in a raid1 to be marked as "write mostly".  Read requests
will only be sent if there is no other option.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Both file-bitmaps and superblock bitmaps are supported.

If you add a bitmap file on the array device, you lose.

This introduces a 'default_bitmap_offset' field in mddev, as the ioctl used
for adding a superblock bitmap doesn't have room for giving an offset.  Later,
this value will be setable via sysfs.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When we find a 'stale' bitmap, possibly because it is new, we should just
assume every bit needs to be set, but rather base the setting of bits on the
current state of the array (degraded and recovery_cp).
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

... otherwise we loose a reference and can never free the file.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix another bug in dm-raid1.c that the dirty region may stay in or be moved
to clean list and freed while in use.

It happens as follows:

   CPU0                                   CPU1
   ------------------------------------------------------------------------------
   rh_dec()
     if (atomic_dec_and_test(pending))
        <the region is still marked dirty>
                                          rh_inc()
                                            if the region is clean
                                               mark the region dirty
                                               and remove from clean list
        mark the region clean
        and move to clean list
                                                  atomic_inc(pending)

At this stage, the region is in clean list and will be mistakenly reclaimed
by rh_update_states() later.
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

md does not yet support BIO_RW_BARRIER, so be honest about it and fail
(-EOPNOTSUPP) any such requests.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

'this_sector' is a virtual (array) address while 'head_position' is a physical
(device) address, so substraction doesn't make any sense.  devs[slot].addr
should be used instead of this_sector.

However, this patch doesn't make much practical different to the read
balancing due to the effects of later code.
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Don't just irritate all other kernel developers.  Fix the users first,
then you can re-introduce the must-check infrastructure to avoid new
cases creeping in.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix up fs/compat.c fixes.

This fixes the problem with "Averatec 6240 pcmcia_socket0: unable to
apply power", which was due to the CardBus IOMEM register region being
allocated at an address that was actually inside the RAM window that had
been reserved for video frame-buffers in an UMA setup.

The BIOS _should_ have marked that region reserved in the e820 memory
descriptor tables, but did not.

It is fixed by rounding up the default starting address of PCI memory
allocations, so that we leave a bigger gap after the final known memory
location.  The amount of rounding depends on how big the unused memory
gap is that we can allocate IOMEM from.

Based on example code by Linus.
Acked-by: NGreg KH <greg@kroah.com>
Acked-by: NIvan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Andrew lost this in patch reject resolution, and never noticed, since
the compat code isn't in use on x86.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds lost sockfd_put() in 32bit compat rounting_ioctl() on
64bit platforms
Signed-Off-By: NKirill Korotaev <dev@sw.ru>
Signed-Off-By: NMaxim Giryaev <gem@sw.ru>
Signed-off-By: NLinus Torvalds <torvalds@osdl.org>

This adds a lost fput in 32bit tiocgdev ioctl on x86-64

[ chrisw: Updated to use fget_light/fput_light ]
Signed-Off-By: NKirill Korotaev <dev@sw.ru>
Signed-Off-By: NMaxim Giryaev <gem@sw.ru>
Signed-off-by: NChris Wright <chrisw@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

um has it own set of files for asm-offsets. So for now the
gen-asm-offset macro is just duplicated in the um Makefile.

This may well be the final solution since um is a bit special compared
to other architectures - time will tell.

Also added a dummy arch/um/kernel/asm-offsets.h file to keep kbuild happy.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>