linux.git/block, branch v2.6.26-rc7

block: disable IRQs until data is written to relay channel

2008-06-12T18:20:57+00:00

As we may run relay_reserve from interrupt context we must always disable
IRQs.  This is because a call to relay_reserve may expose previously written
data to use space.

Updated new message code and an old but related comment.

Signed-off-by: Carl Henrik Lunde 
Signed-off-by: Jens Axboe 
Signed-off-by: Linus Torvalds

Fix invalid access errors in blk_lookup_devt

2008-06-09T17:06:24+00:00

Commit 30f2f0eb4bd2c43d10a8b0d872c6e5ad8f31c9a0 ("block: do_mounts -
accept root=") extended blk_lookup_devt() to be
able to look up partitions that had not yet been registered, but in the
process made the assumption that the '&block_class.devices' list only
contains disk devices and that you can do 'dev_to_disk(dev)' on them.

That isn't actually true.  The block_class device list also contains the
partitions we've discovered so far, and you can't just do a
'dev_to_disk()' on those.

So make sure to only work on devices that block/genhd.c has registered
itself, something we can test by checking the 'dev->type' member.  This
makes the loop in blk_lookup_devt() match the other such loops in this
file.

[ We may want to do an alternate version that knows to handle _either_
  whole-disk devices or partitions, but for now this is the minimal fix
  for a series of crashes reported by Mariusz Kozlowski in

	http://lkml.org/lkml/2008/5/25/25

  and Ingo in

	http://lkml.org/lkml/2008/6/9/39 ]

Reported-by: Mariusz Kozlowski 
Reported-by: Ingo Molnar 
Cc: Neil Brown 
Cc: Joao Luis Meloni Assirati 
Acked-by: Kay Sievers 
Cc: Greg Kroah-Hartman 
Signed-off-by: Linus Torvalds

cfq-iosched: fix RCU problem in cfq_cic_lookup()

2008-05-28T12:49:28+00:00

cfq_cic_lookup() needs to properly protect ioc->ioc_data before
dereferencing it and also exclude updaters of ioc->ioc_data as well.

Also add a number of comments documenting why the existing RCU usage
is OK.

Thanks a lot to "Paul E. McKenney"  for
review and comments!

Signed-off-by: Jens Axboe

block: make blktrace use per-cpu buffers for message notes

2008-05-28T12:49:27+00:00

Currently it uses a single static char array, but that risks
being corrupted when multiple users issue message notes at the
same time. Make the buffers dynamically allocated when the trace
is setup and make them per-cpu instead.

The default max message size of 1k is also very large, the
interface is mainly for small text notes. So shrink it to 128 bytes.

Signed-off-by: Jens Axboe

Added in elevator switch message to blktrace stream

2008-05-28T12:49:27+00:00

Signed-off-by: Alan D. Brunelle 
Signed-off-by: Jens Axboe

Added in MESSAGE notes for blktraces

2008-05-28T12:49:27+00:00

Allows messages to be inserted into blktrace streams.

Signed-off-by: Alan D. Brunelle 
Signed-off-by: Jens Axboe

block: reorder cfq_queue to save space on 64bit builds

2008-05-28T12:49:27+00:00

saves 8 bytes of padding & increases objects/slab from 30 to 32 on my
AMD64 config

Signed-off-by: Richard Kennedy 
Signed-off-by: Jens Axboe

block: Move the second call to get_request to the end of the loop

2008-05-28T12:49:27+00:00

In function get_request_wait, the second call to get_request could be
moved to the end of the while loop, because if the first call to
get_request fails, the second call will fail without sleep.

Signed-off-by: Zhang Yanmin 
Signed-off-by: Jens Axboe

Remove blkdev warning triggered by using md

2008-05-15T02:11:15+00:00

As setting and clearing queue flags now requires that we hold a spinlock
on the queue, and as blk_queue_stack_limits is called without that lock,
get the lock inside blk_queue_stack_limits.

For blk_queue_stack_limits to be able to find the right lock, each md
personality needs to set q->queue_lock to point to the appropriate lock.
Those personalities which didn't previously use a spin_lock, us
q->__queue_lock.  So always initialise that lock when allocated.

With this in place, setting/clearing of the QUEUE_FLAG_PLUGGED bit will no
longer cause warnings as it will be clear that the proper lock is held.

Thanks to Dan Williams for review and fixing the silly bugs.

Signed-off-by: NeilBrown 
Cc: Dan Williams 
Cc: Jens Axboe 
Cc: Alistair John Strachan 
Cc: Nick Piggin 
Cc: "Rafael J. Wysocki" 
Cc: Jacek Luczak 
Cc: Prakash Punnoor 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

block: do_mounts - accept root=

2008-05-14T17:37:57+00:00

Some devices, like md, may create partitions only at first access,
so allow root= to be set to a valid non-existant partition of an
existing disk. This applies only to non-initramfs root mounting.

This fixes a regression from 2.6.24 which did allow this to happen and
broke some users machines :(

Acked-by: Neil Brown 
Tested-by: Joao Luis Meloni Assirati 
Cc: stable 
Signed-off-by: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman