o Always use list_del_init() on request queuelist, this allows us to
  sanity check the integrity of the request on insertion and removal.
  So we can complain loudly instead of silently corrupting memory.

o Add references to requests. This is cheap, since we dont have to use
  an atomic variable for it (all puts are inside queue lock). We've had
  a bug in IDE for years where we want to inspect request state after
  io completion, but this is not possible to do race free right now.
  REQ_BLOCK_PC and sgio will need this too, for checking io residual
  etc. This is not just a theoretical race, I've seen it happen.

Cleanup the last_merge logic. There are two reasons for clearing
last_merge when we are dealing with integrity, and these are:

o Clear when handing the request to the driver, so we don't merge on
  a started request.

o Clear when a request is taken off the list. This cannot be done from
  the driver (above case would already have been hit), but it can
  happen
  when we merge two requests.

This makes it a lot nicer, it was always peculiar how we cleared in
put_request.

Make it possible for a device to specify the dma alignment restrictions
it has. This will be used by future infrastructure when mapping in user
pages, and allows us to dma to on ATAPI even though user address and
length is not sector size aligned.

Extend q->prep_rq_fn() to return one of three values:

 o BLKPREP_OK: request is good, return it
 o BLKPREP_KILL: request is bad, end it completely
 o BLKPREP_DEFER: request is good, but we can't take it now

We maintain compatability with old prep functions (if any, outside of
ide-cd). This change is needed or SCSI to use prep function for command
init, if sg table allocation fails we can just defer the request.

Add some missing bits, and make it generally a bit more useful outside
of REQ_PC requests.

Request insertion in the current tree is a mess. We have all sorts of
variants of *elv_add_request*, and it's not at all clear who does what
and with what locks (or not). This patch cleans it up to be:

o __elv_add_request(queue, request, at_end, plug)
      Core function, requires queue lock to be held

o elv_add_request(queue, request, at_end, plug)
      Like __elv_add_request(), but grabs queue lock

o __elv_add_request_pos(queue, request, position)
      Insert request at a given location, lock must be held

We must return -EIO if the command fails (the 5/20/00 sense check is
just helping return more sane info), not -EINVAL. Getting -EINVAL return
on an ioctl if a command fails is less than helpful for applications...

o Split blk_queue_bounce() into a slow and fast path. The fast path is
  inlined, only if we actually need to check the bio for possible
  bounces (and bounce) do we enter __blk_queue_bounce() slow path.

o Fix a nasty bug that could cause corruption for file systems not
  using PAGE_CACHE_SIZE blok size! We were not correctly setting the
  'to' bv_offset correctly.

o Add BIO_BOUNCE flag. Later patches will use this for debug checking.

Make deadline_merge() prefetch the next entry on the list.

wake_up_interruptible() and _sync() calls are reversed in pipe_read().

The attached patches only calls _sync if a schedule() call follows.

The problem was that when the refcount hit 0, it was unconditionally
assuming that it had been added, which is wrong.  The patch below
corrects that, and fixes the Oops when loading the floppy driver.

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

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

Several ports (x86-64,ppc64,sparc64) which do 32bit ioctl emulation
have functions for drivers to let them define their own translation
handlers. So far it was a bit complicated to use because there
was no standard include file that declares the prototypes for this
stuff. Then drivers and other subsystems can start to declare their own
ioctl translation handlers.

This patch add include/linux/ioctl32.h to fix this.

The actual implementation is in arch specific code. It has been coordinated
with DaveM and Anton.

This patch is needed for the x86-64 merge I sent in separate mail.

There is currently no preprocessor symbol that the drivers can test
to see if they should use this. So far they have to check arch symbols.
This will be fixed later when all 64bit ports that need it add the dynamic
ioctl registration API too (that's ia64,s390x,mips64)

This fixes a few files that got lost with the last merge and merges
with 2.5.43/i386.  Only changes architecture specific files.

It depends on one other patch (for linux/ioctl32.h) which I'm sending
separately.

Changes:
- Include missing files (pageattr.c) and Makefile changes
- Update IA32 subsystem. Various small fixes and a big merge
  with sparc64.
- Change HZ to 1000
- Merge some of the 2.5.43/i386 profiling changes. No full oprofile yet.
- Fix many warnings
- Update defconfig
- Various other smaller cleanups and bugfixes.

        * switched to private queues
        * set ->queue

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

        * switched to private queues
        * set ->queue and ->private_data
        * switched to use of ->bd_disk/->rq_disk
        * merged private blocksize, etc. arrays into nbd_dev[]
        * cleaned up

        * switched to private queues
        * set ->queue and ->private_data
	* switched to use of ->rq_disk

	sbpcd.c: removes bogus duplicate definition of sbpcd_lock, use of
CURRENT (we are using private queue) and call of invalidate_buffers() in
->media_changed() (caller does it itself).  That went in a changeset from
davej - looks like a merge problem...
	sr.c: braino in ifdefed printk - s/disk/cd->disk/.  Thanks to jejb
for spotting that one...

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

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

into nuts.ninka.net:/home/davem/src/BK/sparc-2.5

This adds a set of list macros that make handling of list protected
by RCU simpler. The interfaces added are -

list_add_rcu
list_add_tail_rcu
	- Adds an element by taking care of memory barrier (wmb()).

list_del_rcu
	- Deletes an element but doesn't re-initialize the pointers in
	  the element for supporting RCU based traversal.

list_for_each_rcu
__list_for_each_rcu
	- Traversal of RCU protected list - takes care of memory barriers
	  transparently.

This first RCU helper patch adds a read_barrier_depends() primitive
to all archs which is NOP for archs that doesn't require an rmb()
for data dependent reads when writes are ordered using a wmb().
In reality, only alpha requires an rmb(), the rest are NOPs.
It is likely to be necessary in most situations that would use RCU.
Please apply.

 Description :

Sometime ago, during a discussion on lock-free lookups, it was
agreed that an additional memory barrier interface,
read_barrier_depends() that is lighter than an rmb(),
is necessary to make sure that data-dependent reads are not
re-ordered over this barrier. For many processors, data-dependency
enforces order, so this interface is a NOP, but for those that don't
(like alpha), it can be a rmb().

For example, the following code would force ordering (the initial
value of "a" is zero, "b" is one, and "p" is "&a"):

    CPU 0                           CPU 1

    b = 2;
    memory_barrier();
    p = &b;                         q = p;
                                    read_barrier_depends();
                                    d = *q;

because the read of "*q" depends on the read of "p" and these
two reads should be separated by a read_barrier_depends().  However,
the following code, with the same initial values for "a" and "b":

    CPU 0                           CPU 1

    a = 2;
    memory_barrier();
    b = 3;                          y = b;
                                    read_barrier_depends();
                                    x = a;

does not enforce ordering, since there is no data dependency between
the read of "a" and the read of "b".  Therefore, on some CPUs, such
as Alpha, "y" could be set to 3 and "x" to 0.  rmb()
needs to be used here, not read_barrier_depends().

The original discussion can be found at -
http://marc.theaimsgroup.com/?t=100259422200002&r=1&w=2

Explanation of the need for read_barrier_depends()
can be found at http://lse.sf.net/locking/wmbdd.html

This fixes a 'used but not declared' compile error

It ends up trying to list_del() from an uninitialized
list_head.

- Ignore queries for invalid addresses
- MLD for link-local addresses

into nuts.ninka.net:/home/davem/src/BK/net-2.5

into nuts.ninka.net:/home/davem/src/BK/sctp-2.5

- Change {udp,raw}_sendmsg to ip_append_data, work done
by Maxim Giryaev <gem@asplinux.ru>
- Get rid of ip_build_xmit() and helper functions.
Nobody uses it anymore.