Commit Graph

120 Commits

Author SHA1 Message Date
Nick Piggin dd941252a8 shared tag queue barrier comment
Should add some comments for the tag barriers (they won't be so important
if we can switch over to the explicit _lock bitops, but for now we should
make it clear).

Jens' original patch said a barrier after the test_and_clear_bit was also
required. I can't see why (and it would prevent the use of the _lock bitop).

Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
--
2007-09-14 13:56:47 -07:00
Jens Axboe f3da54ba14 Fix race with shared tag queue maps
There's a race condition in blk_queue_end_tag() for shared tag maps,
users include stex (promise supertrak thingy) and qla2xxx.  The former
at least has reported bugs in this area, not sure why we haven't seen
any for the latter.  It could be because the window is narrow and that
other conditions in the qla2xxx code hide this.  It's a real bug,
though, as the stex smp users can attest.

We need to ensure two things - the tag bit clearing needs to happen
AFTER we cleared the tag pointer, as the tag bit clearing/setting is
what protects this map.  Secondly, we need to ensure that the visibility
of the tag pointer and tag bit clear are ordered properly.

[ I removed the SMP barriers - "test_and_clear_bit()" already implies
  all the required barriers.  -- Linus ]

Also see http://bugzilla.kernel.org/show_bug.cgi?id=7842

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-13 08:20:25 -07:00
Alan D. Brunelle c7149d6bce Fix remap handling by blktrace
This patch provides more information concerning REMAP operations on block
IOs. The additional information provides clearer details at the user level,
and supports post-processing analysis in btt.

o  Adds in partition remaps on the same device.
o  Fixed up the remap information in DM to be in the right order
o  Sent up mapped-from and mapped-to device information

Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-08-11 22:34:48 +02:00
Jens Axboe 165125e1e4 [BLOCK] Get rid of request_queue_t typedef
Some of the code has been gradually transitioned to using the proper
struct request_queue, but there's lots left. So do a full sweet of
the kernel and get rid of this typedef and replace its uses with
the proper type.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-24 09:28:11 +02:00
Paul Mundt 20c2df83d2 mm: Remove slab destructors from kmem_cache_create().
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-20 10:11:58 +09:00
Christoph Lameter 94f6030ca7 Slab allocators: Replace explicit zeroing with __GFP_ZERO
kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing
variant in the past.  But with __GFP_ZERO it is possible now to do zeroing
while allocating.

Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever
we can.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:02 -07:00
FUJITA Tomonori abae1fde63 add a struct request pointer to the request structure
This adds a struct request pointer to the request structure for the
second data phase (bidi for now). A request queue supporting bidi
requests sets QUEUE_FLAG_BIDI. This prevents sending bidi requests to
a non-bidi queue.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-16 08:52:46 +02:00
FUJITA Tomonori 4e2872d6b0 bind bsg to all SCSI devices
This patch binds bsg to all SCSI devices (their request queues) like
the current sg driver does. We can send SCSI commands to non disk and
cdrom scsi devices like OSD via bsg.

This patch removes bsg_register_queue from blk_register_queue so bsg
devices aren't bound to non SCSI block devices. If they want bsg, I'll
send a patch to do that.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-16 08:52:46 +02:00
FUJITA Tomonori d351af01b9 bsg: bind bsg to request_queue instead of gendisk
This patch binds bsg devices to request_queue instead of gendisk. Any
objects (like transport entities) can define own request_handler and
create own bsg device.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-16 08:52:46 +02:00
Jens Axboe 3d6392cfbd bsg: support for full generic block layer SG v3
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-16 08:52:44 +02:00
Tejun Heo f4b09303d0 [BLOCK] drop unnecessary bvec rewinding from flush_dry_bio_endio
Barrier bios are completed twice - once after the barrier write itself
is done and again after the whole sequence is complete.
flush_dry_bio_endio() is for the first completion.  It doesn't really
complete the bio.  It rewinds bvec and resets bio so that it can be
completed again when the whole barrier sequence is complete.

The bvec rewinding code has the following problems.

1. The rewinding code is wrong because filesystems may pass bvec with
   non zero bv_offset.

2. The block layer doesn't guarantee anything about the state of
   bvec array on request completion.  bv_offset and len are updated
   iff __end_that_request_first() completes the bvec partially.

Because of #2, #1 doesn't really matter (nobody cares whether bvec is
re-wound correctly or not) but then again by not doing unwinding at
all, we'll always give back the same bvec to the caller as full bvec
completion doesn't alter bvecs and the final completion is always full
completion.

Drop unnecessary rewinding code.

This is spotted by Neil Brown.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-10 08:03:33 +02:00
Jens Axboe 32eef96411 blk_hw_contig_segment(): bad segment size checks
Two bugs in there:

- The virt oversize check should use the current bio hardware back
  size and the next bio front size, not the same bio. Spotted by
  Neil Brown.

- The segment size check should add hw front sizes, not total bio
  sizes. Spotted by James Bottomley

Acked-by: James Bottomley <James.Bottomley@SteelEye.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-10 08:03:32 +02:00
Tejun Heo bc90ba093a block: always requeue !fs requests at the front
SCSI marks internal commands with REQ_PREEMPT and push it at the front
of the request queue using blk_execute_rq().  When entering suspended
or frozen state, SCSI devices are quiesced using
scsi_device_quiesce().  In quiesced state, only REQ_PREEMPT requests
are processed.  This is how SCSI blocks other requests out while
suspending and resuming.  As all internal commands are pushed at the
front of the queue, this usually works.

Unfortunately, this interacts badly with ordered requeueing.  To
preserve request order on requeueing (due to busy device, active EH or
other failures), requests are sorted according to ordered sequence on
requeue if IO barrier is in progress.

The following sequence deadlocks.

1. IO barrier sequence issues.

2. Suspend requested.  Queue is quiesced with part or all of IO
   barrier sequence at the front.

3. During suspending or resuming, SCSI issues internal command which
   gets deferred and requeued for some reason.  As the command is
   issued after the IO barrier in #1, ordered requeueing code puts the
   request after IO barrier sequence.

4. The device is ready to process requests again but still is in
   quiesced state and the first request of the queue isn't
   REQ_PREEMPT, so command processing is deadlocked -
   suspending/resuming waits for the issued request to complete while
   the request can't be processed till device is put back into
   running state by resuming.

This can be fixed by always putting !fs requests at the front when
requeueing.

The following thread reports this deadlock.

  http://thread.gmane.org/gmane.linux.kernel/537473

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: David Greaves <david@dgreaves.com>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-15 16:12:20 -07:00
Jens Axboe f653c34dd3 ll_rw_blk: fix gcc 4.2 warning on current_io_context()
current_io_context() is both static and exported with EXPORT_SYMBOL().
As there are no users outside of ll_rw_blk.c itself, just kill the
export.

Problem reported by Martin Michlmayr <tbm@cyrius.com>

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-15 10:44:15 -07:00
Neil Brown d89d87965d When stacked block devices are in-use (e.g. md or dm), the recursive calls
to generic_make_request can use up a lot of space, and we would rather they
didn't.

As generic_make_request is a void function, and as it is generally not
expected that it will have any effect immediately, it is safe to delay any
call to generic_make_request until there is sufficient stack space
available.

As ->bi_next is reserved for the driver to use, it can have no valid value
when generic_make_request is called, and as __make_request implicitly
assumes it will be NULL (ELEVATOR_BACK_MERGE fork of switch) we can be
certain that all callers set it to NULL.  We can therefore safely use
bi_next to link pending requests together, providing we clear it before
making the real call.

So, we choose to allow each thread to only be active in one
generic_make_request at a time.  If a subsequent (recursive) call is made,
the bio is linked into a per-thread list, and is handled when the active
call completes.

As the list of pending bios is per-thread, there are no locking issues to
worry about.

I say above that it is "safe to delay any call...".  There are, however,
some behaviours of a make_request_fn which would make it unsafe.  These
include any behaviour that assumes anything will have changed after a
recursive call to generic_make_request.

These could include:
 - waiting for that call to finish and call it's bi_end_io function.
   md use to sometimes do this (marking the superblock dirty before
   completing a write) but doesn't any more
 - inspecting the bio for fields that generic_make_request might
   change, such as bi_sector or bi_bdev.  It is hard to see a good
   reason for this, and I don't think anyone actually does it.
 - inspecing the queue to see if, e.g. it is 'full' yet.  Again, I
   think this is very unlikely to be useful, or to be done.

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <dm-devel@redhat.com>

Alasdair G Kergon <agk@redhat.com> said:

 I can see nothing wrong with this in principle.

 For device-mapper at the moment though it's essential that, while the bio
 mappings may now get delayed, they still get processed in exactly
 the same order as they were passed to generic_make_request().

 My main concern is whether the timing changes implicit in this patch
 will make the rare data-corrupting races in the existing snapshot code
 more likely. (I'm working on a fix for these races, but the unfinished
 patch is already several hundred lines long.)

 It would be helpful if some people on this mailing list would test
 this patch in various scenarios and report back.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-05-11 13:28:37 +02:00
Linus Torvalds 9a9136e270 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (25 commits)
  sound: convert "sound" subdirectory to UTF-8
  MAINTAINERS: Add cxacru website/mailing list
  include files: convert "include" subdirectory to UTF-8
  general: convert "kernel" subdirectory to UTF-8
  documentation: convert the Documentation directory to UTF-8
  Convert the toplevel files CREDITS and MAINTAINERS to UTF-8.
  remove broken URLs from net drivers' output
  Magic number prefix consistency change to Documentation/magic-number.txt
  trivial: s/i_sem /i_mutex/
  fix file specification in comments
  drivers/base/platform.c: fix small typo in doc
  misc doc and kconfig typos
  Remove obsolete fat_cvf help text
  Fix occurrences of "the the "
  Fix minor typoes in kernel/module.c
  Kconfig: Remove reference to external mqueue library
  Kconfig: A couple of grammatical fixes in arch/i386/Kconfig
  Correct comments in genrtc.c to refer to correct /proc file.
  Fix more "deprecated" spellos.
  Fix "deprecated" typoes.
  ...

Fix trivial comment conflict in kernel/relay.c.
2007-05-09 12:54:17 -07:00
Rafael J. Wysocki 8bb7844286 Add suspend-related notifications for CPU hotplug
Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:56 -07:00
Oleg Nesterov 28e53bddf8 unify flush_work/flush_work_keventd and rename it to cancel_work_sync
flush_work(wq, work) doesn't need the first parameter, we can use cwq->wq
(this was possible from the very beginnig, I missed this).  So we can unify
flush_work_keventd and flush_work.

Also, rename flush_work() to cancel_work_sync() and fix all callers.
Perhaps this is not the best name, but "flush_work" is really bad.

(akpm: this is why the earlier patches bypassed maintainers)

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Auke Kok <auke-jan.h.kok@intel.com>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:53 -07:00
Andrew Morton 19a75d83ff kblockd: use flush_work
Switch the kblockd flushing from a global flush to a more specific
flush_work().

(akpm: bypassed maintainers, sorry.  There are other patches which depend on
this)

Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:51 -07:00
Michael Opdenacker 59c51591a0 Fix occurrences of "the the "
Signed-off-by: Michael Opdenacker <michael@free-electrons.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-05-09 08:57:56 +02:00
Mike Christie 821de3a27b [PATCH] ll_rw_blk: fix missing bounce in blk_rq_map_kern()
I think we might just need the blk_map_kern users now. For the async
execute I added the bounce code already and the block SG_IO has it
atleady. I think the blk_map_kern bounce code got dropped because we
thought the correct gfp_t would be passed in. But I think all we need is
the patch below and all the paths are take care of. The patch is not
tested. Patch was made against scsi-misc.

The last place that is sending non sg commands may just be md/dm-emc.c
but that is is just waiting on alasdair to take some patches that fix
that and a bunch of junk in there including adding bounce support. If
the patch below is ok though and dm-emc finally gets converted then it
will have sg and bonce buffer support.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-05-08 19:12:23 +02:00
Linus Torvalds 4f7a307dc6 Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (87 commits)
  [SCSI] fusion: fix domain validation loops
  [SCSI] qla2xxx: fix regression on sparc64
  [SCSI] modalias for scsi devices
  [SCSI] sg: cap reserved_size values at max_sectors
  [SCSI] BusLogic: stop using check_region
  [SCSI] tgt: fix rdma transfer bugs
  [SCSI] aacraid: fix aacraid not finding device
  [SCSI] aacraid: Correct SMC products in aacraid.txt
  [SCSI] scsi_error.c: Add EH Start Unit retry
  [SCSI] aacraid: [Fastboot] Panics for AACRAID driver during 'insmod' for kexec test.
  [SCSI] ipr: Driver version to 2.3.2
  [SCSI] ipr: Faster sg list fetch
  [SCSI] ipr: Return better qc_issue errors
  [SCSI] ipr: Disrupt device error
  [SCSI] ipr: Improve async error logging level control
  [SCSI] ipr: PCI unblock config access fix
  [SCSI] ipr: Fix for oops following SATA request sense
  [SCSI] ipr: Log error for SAS dual path switch
  [SCSI] ipr: Enable logging of debug error data for all devices
  [SCSI] ipr: Add new PCI-E IDs to device table
  ...
2007-05-05 13:30:44 -07:00
Jens Axboe 4e521c27ee ll_rw_blk: add io_context private pointer
To be used by as/cfq as they see fit.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-04-30 09:01:23 +02:00
Alan Stern 44ec95425c [SCSI] sg: cap reserved_size values at max_sectors
This patch (as857) modifies the SG_GET_RESERVED_SIZE and
SG_SET_RESERVED_SIZE ioctls in the sg driver, capping the values at
the device's request_queue's max_sectors value.  This will permit
cdrecord to obtain a legal value for the maximum transfer length,
fixing Bugzilla #7026.

The patch also caps the initial reserved_size value.  There's no
reason to have a reserved buffer larger than max_sectors, since it
would be impossible to use the extra space.

The corresponding ioctls in the block layer are modified similarly,
and the initial value for the reserved_size is set as large as
possible.  This will effectively make it default to max_sectors.
Note that the actual value is meaningless anyway, since block devices
don't have a reserved buffer.

Finally, the BLKSECTGET ioctl is added to sg, so that there will be a
uniform way for users to determine the actual max_sectors value for
any raw SCSI transport.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-04-17 18:09:56 -04:00
Vasily Tarasov f772b3d9ca block: blk_max_pfn is somtimes wrong
There is a small problem in handling page bounce.

At the moment blk_max_pfn equals max_pfn, which is in fact not maximum
possible _number_ of a page frame, but the _amount_ of page frames.  For
example for the 32bit x86 node with 4Gb RAM, max_pfn = 0x100000, but not
0xFFFF.

request_queue structure has a member q->bounce_pfn and queue needs bounce
pages for the pages _above_ this limit.  This routine is handled by
blk_queue_bounce(), where the following check is produced:

	if (q->bounce_pfn >= blk_max_pfn)
		return;

Assume, that a driver has set q->bounce_pfn to 0xFFFF, but blk_max_pfn
equals 0x10000.  In such situation the check above fails and for each bio
we always fall down for iterating over pages tied to the bio.

I want to notice, that for quite a big range of device drivers (ide, md,
...) such problem doesn't happen because they use BLK_BOUNCE_ANY for
bounce_pfn.  BLK_BOUNCE_ANY is defined as blk_max_pfn << PAGE_SHIFT, and
then the check above doesn't fail.  But for other drivers, which obtain
reuired value from drivers, it fails.  For example sata_nv uses
ATA_DMA_MASK or dev->dma_mask.

I propose to use (max_pfn - 1) for blk_max_pfn.  And the same for
blk_max_low_pfn.  The patch also cleanses some checks related with
bounce_pfn.

Signed-off-by: Vasily Tarasov <vtaras@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-03-27 08:52:47 +02:00
Neil Brown 387bb17374 [PATCH] md: fix various bugs with aligned reads in RAID5
It is possible for raid5 to be sent a bio that is too big for an underlying
device.  So if it is a READ that we pass stright down to a device, it will
fail and confuse RAID5.

So in 'chunk_aligned_read' we check that the bio fits within the parameters
for the target device and if it doesn't fit, fall back on reading through
the stripe cache and making lots of one-page requests.

Note that this is the earliest time we can check against the device because
earlier we don't have a lock on the device, so it could change underneath
us.

Also, the code for handling a retry through the cache when a read fails has
not been tested and was badly broken.  This patch fixes that code.

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: "Kai" <epimetreus@fastmail.fm>
Cc: <stable@suse.de>
Cc: <org@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-09 09:25:46 -08:00
Randy Dunlap af9997e426 [PATCH] fix kernel-doc warnings in 2.6.20-rc1
Fix kernel-doc warnings in 2.6.20-rc1.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-22 08:55:47 -08:00
Jens Axboe 8e5cfc45e7 [PATCH] Fixup blk_rq_unmap_user() API
The blk_rq_unmap_user() API is not very nice. It expects the caller to
know that rq->bio has to be reset to the original bio, and it will
silently do nothing if that is not done. Instead make it explicit that
we need to pass in the first bio, by expecting a bio argument.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-19 11:12:46 +01:00
Jens Axboe 48785bb9fa [PATCH] __blk_rq_unmap_user() fails to return error
If the bio is user copied, the copy back could return -EFAULT. Make
sure we return any error seen during unmapping.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-19 11:07:59 +01:00
Jens Axboe 9c9381f942 [PATCH] __blk_rq_map_user() doesn't need to grab the queue_lock
It was for driver private back_merge_fn hooks, but they don't exist
anymore.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-19 08:34:17 +01:00
Jens Axboe 1aa4f24fe9 [PATCH] Remove queue merging hooks
We have full flexibility of merging parameters now, so we can remove the
hooks that define back/front/request merge strategies. Nobody is using
them anymore.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-19 08:33:11 +01:00
Jens Axboe 2985259b0e [PATCH] ->nr_sectors and ->hard_nr_sectors are not used for BLOCK_PC requests
It's a file system thing, for block requests the only size used in the
io paths is ->data_len as it is in bytes, not sectors.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-19 08:27:31 +01:00
Jens Axboe 7749a8d423 [PATCH] Propagate down request sync flag
We need to do this, otherwise the io schedulers don't get access to the
sync flag. Then they cannot tell the difference between a regular write
and an O_DIRECT write, which can cause a performance loss.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-13 13:02:26 +01:00
Boaz Harrosh 2b02a17920 [PATCH] remove blk_queue_activity_fn
While working on bidi support at struct request level
I have found that blk_queue_activity_fn is actually never used.
The only user is in ide-probe.c with this code:

	/* enable led activity for disk drives only */
	if (drive->media == ide_disk && hwif->led_act)
		blk_queue_activity_fn(q, hwif->led_act, drive);

And led_act is never initialized anywhere.
(Looking back at older kernels it was used in the PPC arch, but was removed around 2.6.18)
Unless it is all for future use off course.
(this patch is against linux-2.6-block.git as off 2006/12/4)

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-12 10:22:23 +01:00
Andrew Morton faccbd4b26 [PATCH] io-accounting: read accounting
Wire up read accounting for block devices, within submit_bio().

Cc: Jay Lan <jlan@sgi.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Cc: David Wright <daw@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10 09:55:41 -08:00
Akinobu Mita c17bb49517 [PATCH] fault-injection capability for disk IO
This patch provides fault-injection capability for disk IO.

Boot option:

fail_make_request=<probability>,<interval>,<space>,<times>

	<interval> -- specifies the interval of failures.

	<probability> -- specifies how often it should fail in percent.

	<space> -- specifies the size of free space where disk IO can be issued
		   safely in bytes.

	<times> -- specifies how many times failures may happen at most.

Debugfs:

/debug/fail_make_request/interval
/debug/fail_make_request/probability
/debug/fail_make_request/specifies
/debug/fail_make_request/times

Example:

	fail_make_request=10,100,0,-1
	echo 1 > /sys/blocks/hda/hda1/make-it-fail

generic_make_request() on /dev/hda1 fails once per 10 times.

Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:02 -08:00
Ingo Molnar 0231606785 [PATCH] hotplug CPU: clean up hotcpu_notifier() use
There was lots of #ifdef noise in the kernel due to hotcpu_notifier(fn,
prio) not correctly marking 'fn' as used in the !HOTPLUG_CPU case, and thus
generating compiler warnings of unused symbols, hence forcing people to add
#ifdefs.

the compiler can skip truly unused functions just fine:

    text    data     bss     dec     hex filename
 1624412  728710 3674856 6027978  5bfaca vmlinux.before
 1624412  728710 3674856 6027978  5bfaca vmlinux.after

[akpm@osdl.org: topology.c fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:39 -08:00
Christoph Lameter e18b890bb0 [PATCH] slab: remove kmem_cache_t
Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:25 -08:00
David Howells 4c1ac1b491 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	drivers/infiniband/core/iwcm.c
	drivers/net/chelsio/cxgb2.c
	drivers/net/wireless/bcm43xx/bcm43xx_main.c
	drivers/net/wireless/prism54/islpci_eth.c
	drivers/usb/core/hub.h
	drivers/usb/input/hid-core.c
	net/core/netpoll.c

Fix up merge failures with Linus's head and fix new compilation failures.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-12-05 14:37:56 +00:00
Mike Christie 0e75f9063f [PATCH] block: support larger block pc requests
This patch modifies blk_rq_map/unmap_user() and the cdrom and scsi_ioctl.c
users so that it supports requests larger than bio by chaining them together.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-01 10:40:55 +01:00
David Howells 65f27f3844 WorkStruct: Pass the work_struct pointer instead of context data
Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.

For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.

To make this work, an extra flag is introduced into the management side of the
work_struct.  This governs auto-release of the structure upon execution.

Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function.  This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated..  This is a
problem if the auxiliary data is taken away (as done by the last patch).

However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems.  But then the work function must itself release the
work_struct by calling work_release().

In most cases, automatic release is fine, so this is the default.  Special
initiators exist for the non-auto-release case (ending in _NAR).


Signed-Off-By: David Howells <dhowells@redhat.com>
2006-11-22 14:55:48 +00:00
Andrew Morton df66b8552b [PATCH] tidy "md: check bio address after mapping through partitions"
Neil's xterms are too wide.

Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03 12:27:55 -08:00
NeilBrown 5ddfe9691c [PATCH] md: check bio address after mapping through partitions.
Partitions are not limited to live within a device.  So we should range
check after partition mapping.

Note that 'maxsector' was being used for two different things.  I have
split off the second usage into 'old_sector' so that maxsector can be still
be used for it's primary usage later in the function.

Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31 08:07:01 -08:00
Andrew Morton 3fcfab16c5 [PATCH] separate bdi congestion functions from queue congestion functions
Separate out the concept of "queue congestion" from "backing-dev congestion".
Congestion is a backing-dev concept, not a queue concept.

The blk_* congestion functions are retained, as wrappers around the core
backing-dev congestion functions.

This proper layering is needed so that NFS can cleanly use the congestion
functions, and so that CONFIG_BLOCK=n actually links.

Cc: "Thomas Maier" <balagi@justmail.de>
Cc: "Jens Axboe" <jens.axboe@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: David Howells <dhowells@redhat.com>
Cc: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:35 -07:00
Thomas Maier 79e2de4bc5 [PATCH] export clear_queue_congested and set_queue_congested
Export the clear_queue_congested() and set_queue_congested() functions
located in ll_rw_blk.c

The functions are renamed to blk_clear_queue_congested() and
blk_set_queue_congested().

(needed in the pktcdvd driver's bio write congestion control)

Signed-off-by: Thomas Maier <balagi@justmail.de>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:35 -07:00
David C Somayajulu f583f4924d [PATCH] helper function for retrieving scsi_cmd given host based block layer tag
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 <michaelc@cs.wisc.edu>
Signed-off-by: David Somayajulu <david.somayajulu@qlogic.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-10-04 19:32:09 +02:00
Jens Axboe 059af497c2 [PATCH] blk_queue_start_tag() shared map race fix
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 <michaelc@cs.wisc.edu>

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:52:34 +02:00
Oleg Nesterov 25034d7a83 [PATCH] exit_io_context: don't disable irqs
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 <oleg@tv-sign.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:31:18 +02:00
Jens Axboe 5404bc7a87 [PATCH] Allow file systems to differentiate between data and meta reads
We can use this information for making more intelligent priority
decisions, and it will also be useful for blktrace.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:29:42 +02:00
Jens Axboe da20a20f3b [PATCH] ll_rw_blk: allow more flexibility for read_ahead_kb store
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 <cbou@mail.ru>

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:29:41 +02:00