linux-toradex.git/block/ll_rw_blk.c, branch v2.6.19-rc2

[PATCH] helper function for retrieving scsi_cmd given host based block layer tag

2006-10-04T17:32:09+00:00

This was necessitated by the need for a function to get back
to a scsi_cmnd, when an hba the posts its (corresponding) completion
interrupt with a block layer tag as its reference.

Signed-off-by: Mike Christie 
Signed-off-by: David Somayajulu 
Signed-off-by: Jens Axboe

[PATCH] blk_queue_start_tag() shared map race fix

2006-09-30T18:52:34+00:00

If we share the tag map between two or more queues, then we cannot
use __set_bit() to set the bit. In fact we need to make sure we
atomically acquire this tag, so loop using test_and_set_bit() to
protect from that.

Noticed by Mike Christie 

Signed-off-by: Jens Axboe

[PATCH] exit_io_context: don't disable irqs

2006-09-30T18:31:18+00:00

We don't need to disable irqs to clear current->io_context, it is protected
by ->alloc_lock. Even IF it was possible to submit I/O from IRQ on behalf of
current this irq_disable() can't help: current_io_context() will re-instantiate
->io_context after irq_enable().

We don't need task_lock() or local_irq_disable() to clear ioc->task. This can't
prevent other CPUs from playing with our io_context anyway.

Signed-off-by: Oleg Nesterov 
Signed-off-by: Jens Axboe

[PATCH] Allow file systems to differentiate between data and meta reads

2006-09-30T18:29:42+00:00

We can use this information for making more intelligent priority
decisions, and it will also be useful for blktrace.

Signed-off-by: Jens Axboe

[PATCH] ll_rw_blk: allow more flexibility for read_ahead_kb store

2006-09-30T18:29:41+00:00

It can make sense to set read-ahead larger than a single request.
We should not be enforcing such policy on the user. Additionally,
using the BLKRASET ioctl doesn't impose such a restriction. So
additionally we now expose identical behaviour through the two.

Issue also reported by Anton 

Signed-off-by: Jens Axboe

[PATCH] Add blk_start_queueing() helper

2006-09-30T18:29:40+00:00

CFQ implements this on its own now, but it's really block layer
knowledge. Tells a device queue to start dispatching requests to
the driver, taking care to unplug if needed. Also fixes the issue
where as/cfq will invoke a stopped queue, which we really don't
want.

Signed-off-by: Jens Axboe

[PATCH] Make sure all block/io scheduler setups are node aware

2006-09-30T18:29:39+00:00

Some were kmalloc_node(), some were still kmalloc(). Change them all to
kmalloc_node().

Signed-off-by: Jens Axboe

[PATCH] Audit block layer inlines

2006-09-30T18:29:38+00:00

Kill a few inlines that bring in too much code to more than one location
Shrinks kernel text by about 300 bytes on 32-bit x86.

Signed-off-by: Jens Axboe

[PATCH] cfq-iosched: kill cfq_exit_lock

2006-09-30T18:29:36+00:00

cfq_exit_lock is protecting two things now:

- The per-ioc rbtree of cfq_io_contexts

- The per-cfqd linked list of cfq_io_contexts

The per-cfqd linked list can be protected by the queue lock, as it is (by
definition) per cfqd as the queue lock is.

The per-ioc rbtree is mainly used and updated by the process itself only.
The only outside use is the io priority changing. If we move the
priority changing to not browsing the rbtree, we can remove any locking
from the rbtree updates and lookup completely. Let the sys_ioprio syscall
just mark processes as having the iopriority changed and lazily update
the private cfq io contexts the next time io is queued, and we can
remove this locking as well.

Signed-off-by: Jens Axboe

[PATCH] ll_rw_blk: cleanup __make_request()

2006-09-30T18:29:34+00:00

- Don't assign variables that are only used once.

- Kill spin_lock() prefetching, it's opportunistic at best.

Signed-off-by: Jens Axboe