By requiring that compound pages implement destructors we can drop some code
from put_page().

->writepage() is supposed to return zero or a negative error code.  Returning
the number of bytes written will confuse the VFS.

We have interesting deadlocks when slab decides to use order-1 allocations for
ext3_inode_cache.  This is because ext3_alloc_inode() needs to perform a
GFP_NOFS 1-order allocation.

Sometimes the 1-order allocation needs to free a huge number of pages (tens of
megabytes) before a 1-order grouping becomes available.  But the GFP_NOFS
allocator cannot free dcache (and hence icache) due to the deadlock problems
identified in shrink_dcache_memory().

So change slab so that it will force 0-order allocations for shrinkable VFS
objects.  We can handle those OK.

From: Marek Szuba <scriptkiddie@wp.pl>

Use the configured default NLS rather than hardwire it.

From: Matt Mackall <mpm@selenic.com>

This function doesn't correctly accumulate -EIO for its caller.

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

This patch add a system control that allows to switch off the jiffies timer
interrupts while a cpu sleeps in idle.  This is useful for a system running
with virtual cpus under z/VM.

From: Matt Domsch <Matt_Domsch@dell.com>

I moved the home of the efibootmgr utility from domsch.com to
linux.dell.com.  Note the move in drivers/firmware/Kconfig, also note
version 0.5.0-test3 or above is necessary.

From: Matt Domsch <Matt_Domsch@dell.com>

Patch below fixes three small bugs in efivars.c as posted by Matt Tolentino
last week and included in the latest -mm.  Aside from this small patch, I'm
quite pleased with Matt T's work, thanks!

- dummy() used for reading write-only sysfs files should return -ENODEV to
  indicate failure, not 0.

- efivar_create() should return the number of bytes written on success, not
  zero.

- efivar_delete() should return the number of bytes written on success, not
  zero.

From: Matt Tolentino <metolent@snoqualmie.dp.intel.com>

Third efivars driver update patch that removes x86 references to the /proc
version of the driver.

From: Matt Tolentino <metolent@snoqualmie.dp.intel.com>

Second efivars driver update patch that adds efivars into the drivers/firmware
directory.

From: Matt Tolentino <metolent@snoqualmie.dp.intel.com>

I broke up the efivars driver update patch I had sent out quite a while ago
into several smaller patches.  This includes several fixes and suggestions
that were pointed out.  The patches are broken down as follows:

1 - remove all traces of efivars from arch/ia64/
2 - add new sysfs based efivars driver into
    drivers/firmware with accompanying Kconfig/Makefile
    changes to make it fully functional for ia64 again.
3 - cleans up x86 references to the /proc version of
    the efivars driver.

From: Geert Uytterhoeven <geert@linux-m68k.org>

M68k bitops updates (from Roman Zippel):
  - Optimize find_{first,next}_zero_bit()
  - Add missing implementations of find_{first,next}_bit()

From: Geert Uytterhoeven <geert@linux-m68k.org>

Amiga A2065 Ethernet: Add KERN_* prefixes to printk() messages

From: Maneesh Soni <maneesh@in.ibm.com>

Clarify some things which were confusing poeple...

From: Manfred Spraul <manfred@colorfullife.com>

Below is a patch that redefines the kmem_cache_alloc `align' argument:

- align not zero: use the specified alignment.  I think values smaller than
  sizeof(void*) will work, even on archs with strict alignment requirement (or
  at least: slab shouldn't crash.  Obviously the user must handle the
  alignment properly).

- align zero:
* debug on: align to sizeof(void*)
* debug off, SLAB_HWCACHE_ALIGN clear: align to sizeof(void*)
* debug off, SLAB_HWCACHE_ALIGN set: align to the smaller of
   - cache_line_size()
   - the object size, rounded up to the next power of two.
  Slab never honored cache align for tiny objects: otherwise the 32-byte
  kmalloc objects would use 128 byte objects.

There is one additional point: right now slab uses ints for the bufctls.
Using short would save two bytes for each object.  Initially I had used short,
but davem objected.  IIRC because some archs do not handle short efficiently. 
Should I allow arch overrides for the bufctls?  On i386, saving two bytes
might allow a few additional anon_vma objects in each page.

From: Paul Jackson <pj@sgi.com>

The #include of linux/module.h in several arch/*/mm/hugetlbpage.c files for
EXPORT_SYMBOL(hugetlb_total_pages) is now unneeded.

From: Rusty Russell <rusty@rustcorp.com.au>

Doesn't compile with CONFIG_BLK_DEV_INITRD=n.  Be more careful with the
conditionals.

Spotted by Dave Boutcher...

From: Rusty Russell <rusty@rustcorp.com.au>

This patch moves the initrd when "make_room" runs out of space, rather than
stepping over it.  The problem with stepping over it is that it gets copied
with the kernel when this happens, which wastes space.

Also ensures that the initrd isn't where the kernel wants to be moved to: if
it is, it gets moved out the way.

From: Rusty Russell <rusty@rustcorp.com.au>

Clean up initrd handling.

1) Expose initrd_start and initrd_end to prom.c (replacing its local
   initrd_start and initrd_len).

2) Don't hand mem (aka klimit) through functions which don't need it.

3) Add more debugging under DEBUG_PROM in case we broke anything.

From: Rusty Russell <rusty@rustcorp.com.au>

1) Define PROM_ERROR: checks for call_prom() < 0 are bogus (returns ulong)
2) All OF access functions should be marked __init.
3) prom_strtoul isn't used at all.

From: Rusty Russell <rusty@rustcorp.com.au>

Ben Herrenschmidt made this actually boot.

From: Rusty Russell <rusty@rustcorp.com.au>

copy_device_tree calls inspect_node() which recurses to copy the Open Firmware
device tree.  It just copied into memory above the kernel for about 8MB, which
can overwrite the initrd, and/or get truncated on big machines.

The real solution is to allocate memory properly for all the prom_init memory
users.  However, that's quite a change.  This patch introduces a "make_room"
macro which inspect_node uses to get memory.  This does the same as before,
except skips over the initrd if neccessary.

From: Rusty Russell <rusty@rustcorp.com.au>

finish_device_tree simply allocates nodes by incrementing klimit (ie.  using
memory on top of the kernel).  Change it to figure out how much memory it
needs, then use lmb_alloc to allocate that, then fill it in.

This gets rid of the only manipulation of klimit after prom_init.

From: Rusty Russell <rusty@rustcorp.com.au>

Rather than pre-declaring static functions, order them so it's not neccessary.
This makes the code easier to navigate and patch.

From: Rusty Russell <rusty@rustcorp.com.au>

Rather than pre-declaring static functions, order them so it's not neccessary.
This makes the code easier to navigate and patch.

From: Rusty Russell <rusty@rustcorp.com.au>

Rather than pre-declaring static functions, order them so it's not neccessary.
This makes the code easier to navigate and patch.

From: Rusty Russell <rusty@rustcorp.com.au>

Rather than pre-declaring static functions, order them so it's not neccessary.
This makes the code easier to navigate and patch.

From: Rusty Russell <rusty@rustcorp.com.au>

Move all the functions that run normally (ie.  with the kernel in the correct
address) to the bottom of prom.c, and keep all the functions which use RELOC()
to the top, above "prom_init()" which calls them.

Also, make prom_initialize_dart_table and prom_initialize_tce_table static.

From: Jan Kara <jack@ucw.cz>

It fixes a memory leak when turning journalled quotas off.

We're testing the nullness of `sb' potentially after rereferencing it
(although the compiler will have reordered things to avoid such a bug).

Just remove the test - the superblock pointer shouldn't be null in there.

From: Jan Kara <jack@ucw.cz>

When there are lots of dirty dquots the vfs_quota_sync() is too slow (it has
O(N^2) behaviour).  Attached patch implements list of dirty dquots for each
superblock and quota type.  Using this lists sync is trivially linear.
Attached patch is against 2.6.5 with journalled quota and previous patch for
hash table size.

(Jan had a test which went from 8 minutes to 0.8 seconds...)

From: Jan Kara <jack@ucw.cz>

I found out that quota uses hash table with just 43 entries to hash dquot
entries.  I guess that we can afford using one page for that
(quotactl(Q_GETQUOTA...), got faster like 3x for 4000 users).  Attached patch
implements that.

From: Jan Kara <jack@ucw.cz>

I've attached a fix for a problem in ext3 journalled quota patch - the problem
is that detecting whether dqput() sleeps was wrong and so we could possibly
schedule when holding a spinlock.

From: Chris Wright <chrisw@osdl.org>

Contributions from:
Stephen Smalley <sds@epoch.ncsc.mil>
Andy Lutomirski <luto@stanford.edu>

During exec the LSM bprm_apply_creds() hooks may tranisition the program to a
new security context (like setuid binaries).  The security context of the new
task is dependent on state such as if the task is being ptraced.  

ptrace_detach() doesn't take the task_lock() when clearing task->ptrace.  So
there is a race possible where a process starts off being ptraced, the
malicious ptracer detaches and if any checks agains task->ptrace are done more
than once, the results are indeterminate.

This patch ensures task_lock() is held while bprm_apply_creds() hooks are
called, keeping it safe against ptrace_attach() races.  Additionally, tests
against task->ptrace (and ->fs->count, ->files->count and ->sighand->count all
of which signify potential unsafe resource sharing during a security context
transition) are done only once the results are passed down to hooks, making it
safe against ptrace_detach() races.

Additionally:

- s/must_must_not_trace_exec/unsafe_exec/
- move unsafe_exec() call above security_bprm_apply_creds() call rather than
  in call for readability.
- fix dummy hook to honor the case where root is ptracing
- couple minor formatting/spelling fixes

From: Chris Mason <mason@suse.com>

block_write_full_page might see and lock clean metadata buffers, which leads
to bogus vs-12339 messages.  Change the message to ignore bh locked.

From: Rusty Russell <rusty@rustcorp.com.au>

call_usermodehelper uses keventd to create a thread, guaranteeing a nice,
clean kernel thread.  Unfortunately, there is a case where
call_usermodehelper is called with &bus->subsys.rwsem held (via
bus_add_driver()), but keventd could be running bus_add_device(), which is
blocked on the same lock.  The result is deadlock, and it comes from using
keventd for both.

In this case, it can be fixed by using a completely independent thread for
call_usermodehelper, or an independent workqueue.  Workqueues have the
infrastructure we need, so we use one.

Move EXPORT_SYMBOL while we're there, too.

akpm fixes: Make it compile with !CONFIG_KMOD

From: Rusty Russell <rusty@rustcorp.com.au>

Workqueues are a great primitive for running things from user context from
a completely clean environment.  Unfortunately, they currently insist on
creating one thread per CPU, which is overkill for many situations, so the
more generic keventd workqueue is used for these.  Recently deadlocks using
keventd were demonstrated, showing that it is not suitable for all uses.

1) Clean up CPU iterators.  Always a nice touch.

2) Add __create_workqueue() and create_singlethread_workqueue(),
   keeping source compatibility.

3) Put workqueues in workqueue list even if !CONFIG_HOTPLUG_CPU (means
   we need a lock to protect that list).  Now we can tell if a wq is
   single-threaded using list_empty(&wq->list).

4) For single-threaded workqueues, override CPU in queue_work,
   delayed_work_timer_fn and flush_workqueue to be 0.  flush_workqueue
   now does redundant passes for single-threaded workqueues, but the
   code remains simple.

5) Make create_workqueue_thread return the thread, so we can easily
   kthread_bind for multi-threaded workqueues.


akpm fixes:

- Fix up is_single_threaded() handling

- single-threaded wq thread does not have "/0" appended.

Here's another fix it'd be good to merge ...

No changes to the Linux code at all, but it'll makes the Windows
configuration of a Linux device running the Ethernet/RNDIS gadget behave
correctly on more versions of Windows.  (It might prevent some
Bluescreening too.)