into kroah.com:/home/linux/linux/BK/gregkh-2.5

This patch removes BKL protection from the invocation of the
super_operations ->statfs() method, and shifts it into the filesystems
where necessary. Any out-of-tree filesystems may need to take the BKL in
their statfs() methods if they were relying on it for synchronisation.

All ->statfs() implementations have been modified to take the BKL,
except for those that don't reference any external mutable data or that
already have their own locking.

Additionally, capifs is changed to use simple_statfs rather than its
own home-grown version.

The BKL change has been flagged at the end of
Documentation/filesystems/porting, along with the recent change to
->permission BKL usage.

into home.transmeta.com:/home/torvalds/v2.5/linux

into home.transmeta.com:/home/torvalds/v2.5/linux

into tp1.ruhr-uni-bochum.de:/home/kai/kernel/v2.5/linux-2.5.make

I chose a little bit more restrictive license for my drivers.
Rx skb pool introduced in pegasus driver and the pool locking in rtl8150
is refined.

into home.transmeta.com:/home/torvalds/v2.5/linux

	* ->i_dev followed the example of ->s_dev - it's dev_t now.  All
remaining uses of ->i_dev either outright want dev_t (stat()) or couldn't
care less (printing major:minor in /proc/<pid>/maps, etc.)

	* JFS uses its ->logdev only twice - one of the places assigns
it to_kdev_t(le32_to_cpu(...)), another uses kdev_t_to_nr() of it.
Switched to u32 - it's just a place where we store device number we'd got
from superblock.
	* several reiserfs_fs.h function prototypes removed - functions
in question don't exist anymore.
	* smbfs doesn't support device nodes; ->f_rdev removed.

	* svc_export ->ex_dev turned into dev_t.  It's a pure search
key and all places that set it actually do to_kdev_t(some_dev_t_expression).

	* ->dev killed for md/linear.c (same as previous parts)

	* md_import_device() returns resulting rdev or ERR_PTR(error)
instead of returning 0 or error an letting caller find rdev.

	* a bunch of callers of partition_name() are calling
bdev_partition_name(),
	* the last users of raid1 and multipath ->dev are gone; so are
the fields in question.

	* ->diskop() split into individual methods; prototypes cleaned
up.  In particular, handling of hot_add_disk() gets mdk_rdev_t * of
the component we are adding as an argument instead of playing the games
with major/minor.  Code cleaned up.

	* ->error_handler() switched to struct block_device *.
	* md_sync_acct() switched to struct block_device *.
	* raid5 struct disk_info ->dev is gone - we use ->bdev everywhere.
	* bunch of kdev_same() when we have corresponding struct block_device *
and can simply compare them is removed from drivers/md/*.c

	* since the last caller of is_read_only() is gone, the function
itself is removed.
	* destroy_buffers() is not used anymore; gone.
	* fsync_dev() is gone; the only user is (broken) lvm.c and first
step in fixing lvm.c will consist of propagating struct block_device *
anyway; at that point we'll just use fsync_bdev() in there.
	* prototype of bio_ioctl() removed - function doesn't exist
anymore.

	* Bunch of functions in cdrom.c used to get kdev_t and use it
only to do cdrom_find_device(dev), even though their callers already
had struct cdrom_device_info * in question.  Switched to passing
said pointer directly.
	* useless exports removed; stuff not used outside of cdrom.c
made static.

	* calc_dev_sboffset() and calc_dev_size() in md.c are getting
mk_rdev_t instead of kdev_t.  Callers updated.
	* calls of blkdev_size_in_bytes() in md.c replaced with use
of rdev->bdev->bd_inode->i_size.

	* devpts "upcalls" eliminated.
	* instead of playing games with revalidation we simply use
ramfs-style tree and kill dentries upon devpts_pty_kill().  That
allows to get rid of a lot of code in fs/devpts/*.c.
	* devpts_fs.h cleaned up.
	* devpts/root.c and devpts/devpts_i.h removed.
	* array of pointers to devpts inodes killed; with ramfs-style tree
it's not needed anymore.
	* devpts/inode.c cleaned up.
	* devpts_pty_new() used to get mk_kdev() only to convert it to
dev_t (hardly a surprise, since it's mknod() in disguise).  Now it gets
dev_t as an argument.

into home.transmeta.com:/home/torvalds/v2.5/linux

This is Bill Irwin's cleanup patch which gives symbolic names to the
fault types:

	#define VM_FAULT_OOM	(-1)
	#define VM_FAULT_SIGBUS	0
	#define VM_FAULT_MINOR	1
	#define VM_FAULT_MAJOR	2

Only arch/i386 has been updated - other architectures can do this too.

The blockdev mapping's private_lock is fairly contended.  The buffer
LRU cache fixed a lot of that, but under page replacement load,
try_to_free_buffers is still showing up.

Moving the freeing of buffer_heads outside the lock reduces contention
in there by 30%.

Add a BUG() check to __free_pages_ok() - to catch someone freeing a
page which has a non-zero refcount.  Actually, this check is mainly to
catch someone (ie: shrink_cache()) incrementing a page's refcount
shortly after it has been freed

Also clean up __free_pages_ok() a bit and convert lots of BUGs to BUG_ON.

Fix a buglet in invalidate_list_pages2(): there is a small window in
which writeback could start against the page before this function locks
it.

The patch closes the race by performing the PageWriteback test inside
PageLocked.

Testing PageWriteback inside PageLocked is "definitive" - when a page
is locked, writeback cannot start against it.

This is a patch which Stephen has applied to ext3's 2.4 repository.
Originally written by Andreas, generalised somewhat by Stephen.

Add jbd callback mechanism, requested for InterMezzo.  We allow the jbd's
client to request notification when a given handle's IO finally commits to
disk, so that clients can manage their own writeback state asynchronously.

Forward-port of a fix which Stephen has applied to ext3's 2.4 CVS tree.

Fix for a rare problem seen under stress in data=journal mode: if we
have to restart a truncate transaction while traversing the inode's
direct blocks, we need to deal with bh==NULL in ext3_clear_blocks.

generic_writepages and mpage_writepages are basically identical,
except one calls ->writepage() and the other calls mpage_writepage().
This duplication is irritating.

The patch folds generic_writepage() into mpage_writepages().  It does
this rather kludgily: if the get_block argument to mpage_writepages()
is NULL then use ->writepage().

Can't think of a better way, really - we could go for a fully-blown
write_actor_t thing, but that would be overly elaborate and would not
allow mpage_writepage() to be inlined inside mpage_writepages(), which
is rather desirable.

Fixes a bug in generic_writepages() and its cut-n-paste-cousin,
mpage_writepages().

The code was clearing PageDirty and then baling out if it discovered
the page was nder writeback.  Which would cause the dirty bit to be
lost.

It's a very small window, but reversing the order so PageDirty is only
cleared when we know for-sure that IO will be started fixes it up.

The `page allocation failure' warning in __alloc_pages() is being a
pain.  But I'm persisting with it...

The patch renames PF_RADIX_TREE to PF_NOWARN, and uses it in a few
places where allocations failures are known to happen.  These code
paths are well-tested now and suppressing the warning is OK.

move_from_swap_cache() and move_to_swap_cache() are playing with
page->flags nonatomically.  The page is on the LRU at the time and
another CPU could be altering page->flags concurrently.

The patch converts those functions to use atomic operations.

It also rationalises the number of bits which are cleared.  It's not
really clear to me what page flags we really want to set to a known
state in there.

It had no right to go clearing PG_arch_1.  I'm now clearing PG_arch_1
inside rmqueue() which is still a bit presumptious.

btw: shmem uses PAGE_CACHE_SIZE and swapper_space uses PAGE_SIZE.  I've
been carefully maintaining the distinction, but it looks like shmem
will break if we ever do make these values different.


Also, __add_to_page_cache() was performing a non-atomic RMW against
page->flags, under the assumption that it was a newly allocated page
which no other CPU would look at.  Not true - this function is used for
moving anon pages into swapcache.  Those anon pages are on the LRU -
other CPUs can be performing operations against page->flags while
__add_to_swap_cache is stomping on them.  This had me running around in
circles for two days.

So let's move the initialisation of the page state into rmqueue(),
where the page really is new (could do it in page_cache_alloc,
perhaps).

The SetPageLocked() in __add_to_page_cache() is also rather curious.
Seems OK for both pagecache and swapcache so I covered that with a
comment.


2.4 has the same problem.  Basically, add_to_swap_cache() can stomp on
another CPU's manipulation of page->flags.  After a quick review of the
code there, it is barely conceivable that a concurrent refill_inactve()
could get its PG_referenced and PG_active bits scribbled on.  Rather
unlikely because swap_out() will probably see PageActive() and bale
out.

Also, mark_dirty_kiobuf() could have its PG_dirty bit accidentally
cleared (but try_to_swap_out() sets it again later).

But there may be other code paths.  Really, I think this needs fixing
in 2.4 - it's horrid.

In mpage_writepage(), use __GFP_HIGH when allocating the BIO: writeback
is a memory reclaim function and is entitle to dip into the page
reserves to get its IO underway.

This patch reinstates __GFP_HIGH functionality.

__GFP_HIGH means "able to dip into the emergency pools".  However,
somewhere along the line this got broken.  __GFP_HIGH ceased to do
anything.  Instead, !__GFP_WAIT is used to tell the page allocator to
try harder.

__GFP_HIGH makes sense.  The concepts of "unable to sleep" and "should
try harder" are quite separate, and overloading !__GFP_WAIT to mean
"should access emergency pools" seems wrong.

This patch fixes a problem in mempool_alloc().  mempool_alloc() tries
the first allocation with __GFP_WAIT cleared.  If that fails, it tries
again with __GFP_WAIT enabled (if the caller can support __GFP_WAIT).
So it is currently performing an atomic allocation first, even though
the caller said that they're prepared to go in and call the page
stealer.

I thought this was a mempool bug, but Ingo said:

> no, it's not GFP_ATOMIC. The important difference is __GFP_HIGH, which
> triggers the intrusive highprio allocation mode. Otherwise gfp_nowait is
> just a nonblocking allocation of the same type as the original gfp_mask.
> ...
> what i've added is a bit more subtle allocation method, with both
> performance and balancing-correctness in mind:
>
> 1. allocate via gfp_mask, but nonblocking
> 2. if failure => try to get from the pool if the pool is 'full enough'.
> 3. if failure => allocate with gfp_mask [which might block]
>
> there is performance data that this method improves bounce-IO performance
> significantly, because even under VM pressure (when gfp_mask would block)
> we can still use up to 50% of the memory pool without blocking (and
> without endangering deadlock-free allocation). Ie. the memory pool is also
> a fast 'frontside cache' of memory elements.

Ingo was assuming that __GFP_HIGH was still functional.  It isn't, and the
mempool design wants it.

Yet another SetPageDirty/set_page_dirty bugfix: mark_dirty_kiobuf needs
to run set_page_dirty() so the page goes onto its mapping's dirty_pages
list.

For O_DIRECT opens we're currently checking that the fs supports
O_DIRECT at write(2)-time.

This is a forward-port of Andrea's patch which moves the check to
open() time.  Seems more sensible.

It seems that the yield() macro requires state TASK_RUNNING, but
practically none of the callers remember to do that.

The patch turns yield() into a real function which sets state
TASK_RUNNING before scheduling.

do_select() does set_current_state(TASK_INTERRUPTIBLE) then calls
__pollwait() which calls __get_free_page() and the cond_resched() which
I added to the pagecache reclaim code never returns.

The patch makes cond_resched() more useful by setting current->state to
TASK_RUNNING before scheduling.

A little cleanup: Most callers of list_splice() immediately
reinitialise the source list_head after calling list_splice().

So create a new list_splice_init() which does all that.

A shmem cleanup/bugfix patch from Hugh Dickins.

- Minor: in try_to_unuse(), only wait on writeout if we actually
  started new writeout.  Otherwise, there is no need because a
  wait_on_page_writeback() has already been executed against this page.
  And it's locked, so no new writeback can start.

- Minor: in shmem_unuse_inode(): remove all the
  wait_on_page_writeback() logic.  We already did that in
  try_to_unuse(), adn the page is locked so no new writeback can start.

- Less minor: add a missing a page_cache_release() to
  shmem_get_page_locked() in the uncommon case where the page was found
  to be under writeout.

Patch from Christoph Hellwig removes swap_get_block().

I was sort-of hanging onto this function because it is a standard
get_block function, and maybe perhaps it could be used to make swap use
the regular filesystem I/O functions.  We don't want to do that, so
kill it.