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Commit Graph

367 Commits

Author SHA1 Message Date
Borislav Petkov
96c1674397 ide-cd: fix REQ_QUIET tests in cdrom_decode_status
Original patch (dfa4411cc3) was buggy.
This is a more proper fix which introduces blk_rq_quiet() macro
alleviating the need for dumb, too short caching variables.

Thanks to Helge Deller and Bart for debugging this.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Reported-and-tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-04-30 18:24:34 +02:00
Tejun Heo
9fd8d0e1bc block: make blk_end_request_cur() return bool
In the process of mindlessly copying [__]blk_end_request_all(),
[__]blk_end_request_cur() ended up returning void even though they're
partial completion functions.  Fix it.

[ Impact: fix braindead API ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-28 08:14:49 +02:00
Tejun Heo
731ec497e5 block: kill rq->data
Now that all block request data transfer is done via bio, rq->data
isn't used.  Kill it.

While at it, make the roles of rq->special and buffer clear.

[ Impact: drop now unncessary field from struct request ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Boaz Harrosh <bharrosh@panasas.com>
2009-04-28 07:37:36 +02:00
Tejun Heo
f06d9a2b52 block: replace end_request() with [__]blk_end_request_cur()
end_request() has been kept around for backward compatibility;
however, it's about time for it to go away.

* There aren't too many users left.

* Its use of @updtodate is pretty confusing.

* In some cases, newer code ends up using mixture of end_request() and
  [__]blk_end_request[_all](), which is way too confusing.

So, add [__]blk_end_request_cur() and replace end_request() with it.
Most conversions are straightforward.  Noteworthy ones are...

* paride/pcd: next_request() updated to take 0/-errno instead of 1/0.

* paride/pf: pf_end_request() and next_request() updated to take
  0/-errno instead of 1/0.

* xd: xd_readwrite() updated to return 0/-errno instead of 1/0.

* mtd/mtd_blkdevs: blktrans_discard_request() updated to return
  0/-errno instead of 1/0.  Unnecessary local variable res
  initialization removed from mtd_blktrans_thread().

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Joerg Dorchain <joerg@dorchain.net>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Laurent Vivier <Laurent@lvivier.info>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: unsik Kim <donari75@gmail.com>
2009-04-28 07:37:36 +02:00
Tejun Heo
40cbbb781d block: implement and use [__]blk_end_request_all()
There are many [__]blk_end_request() call sites which call it with
full request length and expect full completion.  Many of them ensure
that the request actually completes by doing BUG_ON() the return
value, which is awkward and error-prone.

This patch adds [__]blk_end_request_all() which takes @rq and @error
and fully completes the request.  BUG_ON() is added to to ensure that
this actually happens.

Most conversions are simple but there are a few noteworthy ones.

* cdrom/viocd: viocd_end_request() replaced with direct calls to
  __blk_end_request_all().

* s390/block/dasd: dasd_end_request() replaced with direct calls to
  __blk_end_request_all().

* s390/char/tape_block: tapeblock_end_request() replaced with direct
  calls to blk_end_request_all().

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-28 07:37:35 +02:00
Tejun Heo
2e60e02297 block: clean up request completion API
Request completion has gone through several changes and became a bit
messy over the time.  Clean it up.

1. end_that_request_data() is a thin wrapper around
   end_that_request_data_first() which checks whether bio is NULL
   before doing anything and handles bidi completion.
   blk_update_request() is a thin wrapper around
   end_that_request_data() which clears nr_sectors on the last
   iteration but doesn't use the bidi completion.

   Clean it up by moving the initial bio NULL check and nr_sectors
   clearing on the last iteration into end_that_request_data() and
   renaming it to blk_update_request(), which makes blk_end_io() the
   only user of end_that_request_data().  Collapse
   end_that_request_data() into blk_end_io().

2. There are four visible completion variants - blk_end_request(),
   __blk_end_request(), blk_end_bidi_request() and end_request().
   blk_end_request() and blk_end_bidi_request() uses blk_end_request()
   as the backend but __blk_end_request() and end_request() use
   separate implementation in __blk_end_request() due to different
   locking rules.

   blk_end_bidi_request() is identical to blk_end_io().  Collapse
   blk_end_io() into blk_end_bidi_request(), separate out request
   update into internal helper blk_update_bidi_request() and add
   __blk_end_bidi_request().  Redefine [__]blk_end_request() as thin
   inline wrappers around [__]blk_end_bidi_request().

3. As the whole request issue/completion usages are about to be
   modified and audited, it's a good chance to convert completion
   functions return bool which better indicates the intended meaning
   of return values.

4. The function name end_that_request_last() is from the days when it
   was a public interface and slighly confusing.  Give it a proper
   internal name - blk_finish_request().

5. Add description explaning that blk_end_bidi_request() can be safely
   used for uni requests as suggested by Boaz Harrosh.

The only visible behavior change is from #1.  nr_sectors counts are
cleared after the final iteration no matter which function is used to
complete the request.  I couldn't find any place where the code
assumes those nr_sectors counters contain the values for the last
segment and this change is good as it makes the API much more
consistent as the end result is now same whether a request is
completed using [__]blk_end_request() alone or in combination with
blk_update_request().

API further cleaned up per Christoph's suggestion.

[ Impact: cleanup, rq->*nr_sectors always updated after req completion ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Boaz Harrosh <bharrosh@panasas.com>
Cc: Christoph Hellwig <hch@infradead.org>
2009-04-28 07:37:35 +02:00
Tejun Heo
0b302d5aa7 block: kill blk_end_request_callback()
With recent IDE updates, blk_end_request_callback() doesn't have any
user now.  Kill it.

[ Impact: removal of unused convoluted interface ]

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:34 +02:00
Tejun Heo
5efccd17ce block: reorder request completion functions
Reorder request completion functions such that

* All request completion functions are located together.

* Functions which are used by only one caller is put right above the
  caller.

* end_request() is put after other completion functions but before
  blk_update_request().

This change is for completion function cleanup which will follow.

[ Impact: cleanup, code reorganization ]

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:34 +02:00
Tejun Heo
a7f5579234 block: kill blk_start_queueing()
blk_start_queueing() is identical to __blk_run_queue() except that it
doesn't check for recursion.  None of the current users depends on
blk_start_queueing() running request_fn directly.  Replace usages of
blk_start_queueing() with [__]blk_run_queue() and kill it.

[ Impact: removal of mostly duplicate interface function ]

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:33 +02:00
Jerome Marchand
42dad7647a block: simplify I/O stat accounting
This simplifies I/O stat accounting switching code and separates it
completely from I/O scheduler switch code.

Requests are accounted according to the state of their request queue
at the time of the request allocation. There is no need anymore to
flush the request queue when switching I/O accounting state.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-24 08:54:21 +02:00
Jens Axboe
2385327725 block: remove unused REQ_UNPLUG
The request inherits the unplug flag from the bio, but it isn't actually
used. The bio flag stops at __make_request(), which tells it to unplug
after submission. Passing it on to the request doesn't make any sense.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-07 08:59:11 +02:00
Jens Axboe
aeb6fafb8f block: Add flag for telling the IO schedulers NOT to anticipate more IO
By default, CFQ will anticipate more IO from a given io context if the
previously completed IO was sync. This used to be fine, since the only
sync IO was reads and O_DIRECT writes. But with more "normal" sync writes
being used now, we don't want to anticipate for those.

Add a bio/request flag that informs the IO scheduler that this is a sync
request that we should not idle for. Introduce WRITE_ODIRECT specifically
for O_DIRECT writes, and make sure that the other sync writes set this
flag.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-06 08:04:54 -07:00
Jens Axboe
1faa16d228 block: change the request allocation/congestion logic to be sync/async based
This makes sure that we never wait on async IO for sync requests, instead
of doing the split on writes vs reads.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-06 08:04:53 -07:00
Jens Axboe
1e42807918 block: reduce stack footprint of blk_recount_segments()
blk_recalc_rq_segments() requires a request structure passed in, which
we don't have from blk_recount_segments(). So the latter allocates one on
the stack, using > 400 bytes of stack for that. This can cause us to spill
over one page of stack from ext4 at least:

 0)     4560     400   blk_recount_segments+0x43/0x62
 1)     4160      32   bio_phys_segments+0x1c/0x24
 2)     4128      32   blk_rq_bio_prep+0x2a/0xf9
 3)     4096      32   init_request_from_bio+0xf9/0xfe
 4)     4064     112   __make_request+0x33c/0x3f6
 5)     3952     144   generic_make_request+0x2d1/0x321
 6)     3808      64   submit_bio+0xb9/0xc3
 7)     3744      48   submit_bh+0xea/0x10e
 8)     3696     368   ext4_mb_init_cache+0x257/0xa6a [ext4]
 9)     3328     288   ext4_mb_regular_allocator+0x421/0xcd9 [ext4]
10)     3040     160   ext4_mb_new_blocks+0x211/0x4b4 [ext4]
11)     2880     336   ext4_ext_get_blocks+0xb61/0xd45 [ext4]
12)     2544      96   ext4_get_blocks_wrap+0xf2/0x200 [ext4]
13)     2448      80   ext4_da_get_block_write+0x6e/0x16b [ext4]
14)     2368     352   mpage_da_map_blocks+0x7e/0x4b3 [ext4]
15)     2016     352   ext4_da_writepages+0x2ce/0x43c [ext4]
16)     1664      32   do_writepages+0x2d/0x3c
17)     1632     144   __writeback_single_inode+0x162/0x2cd
18)     1488      96   generic_sync_sb_inodes+0x1e3/0x32b
19)     1392      16   sync_sb_inodes+0xe/0x10
20)     1376      48   writeback_inodes+0x69/0xb3
21)     1328     208   balance_dirty_pages_ratelimited_nr+0x187/0x2f9
22)     1120     224   generic_file_buffered_write+0x1d4/0x2c4
23)      896     176   __generic_file_aio_write_nolock+0x35f/0x393
24)      720      80   generic_file_aio_write+0x6c/0xc8
25)      640      80   ext4_file_write+0xa9/0x137 [ext4]
26)      560     320   do_sync_write+0xf0/0x137
27)      240      48   vfs_write+0xb3/0x13c
28)      192      64   sys_write+0x4c/0x74
29)      128     128   system_call_fastpath+0x16/0x1b

Split the segment counting out into a __blk_recalc_rq_segments() helper
to avoid allocating an onstack request just for checking the physical
segment count.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-02-26 10:45:48 +01:00
Jens Axboe
0648e10d71 block: fix inconsistent parenthesisation of QUEUE_FLAG_DEFAULT
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-02-02 08:43:48 +01:00
Jens Axboe
bc58ba9468 block: add sysfs file for controlling io stats accounting
This allows us to turn off disk stat accounting completely, for the cases
where the 0.5-1% reduction in system time is important.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-01-30 12:34:38 +01:00
Jens Axboe
213d9417fe block: seperate bio/request unplug and sync bits
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-01-30 12:34:37 +01:00
FUJITA Tomonori
97ae77a1cd [SCSI] block: make blk_rq_map_user take a NULL user-space buffer for WRITE
The commit 818827669d (block: make
blk_rq_map_user take a NULL user-space buffer) extended
blk_rq_map_user to accept a NULL user-space buffer with a READ
command. It was necessary to convert sg to use the block layer mapping
API.

This patch extends blk_rq_map_user again for a WRITE command. It is
necessary to convert st and osst drivers to use the block layer
apping API.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-01-02 11:10:35 -06:00
FUJITA Tomonori
56c451f4b5 [SCSI] block: fix the partial mappings with struct rq_map_data
This fixes bio_copy_user_iov to properly handle the partial mappings
with struct rq_map_data (which only sg uses for now but st and osst
will shortly). It adds the offset member to struct rq_map_data and
changes blk_rq_map_user to update it so that bio_copy_user_iov can add
an appropriate page frame via bio_add_pc_page().

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-01-02 11:10:08 -06:00
Jens Axboe
b374d18a4b block: get rid of elevator_t typedef
Just use struct elevator_queue everywhere instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:29:50 +01:00
Tejun Heo
58eea927d2 block: simplify empty barrier implementation
Empty barrier required special handling in __elv_next_request() to
complete it without letting the low level driver see it.

With previous changes, barrier code is now flexible enough to skip the
BAR step using the same barrier sequence selection mechanism.  Drop
the special handling and mask off q->ordered from start_ordered().

Remove blk_empty_barrier() test which now has no user.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:45 +01:00
Tejun Heo
8f11b3e99a block: make barrier completion more robust
Barrier completion had the following assumptions.

* start_ordered() couldn't finish the whole sequence properly.  If all
  actions are to be skipped, q->ordseq is set correctly but the actual
  completion was never triggered thus hanging the barrier request.

* Drain completion in elv_complete_request() assumed that there's
  always at least one request in the queue when drain completes.

Both assumptions are true but these assumptions need to be removed to
improve empty barrier implementation.  This patch makes the following
changes.

* Make start_ordered() use blk_ordered_complete_seq() to mark skipped
  steps complete and notify __elv_next_request() that it should fetch
  the next request if the whole barrier has completed inside
  start_ordered().

* Make drain completion path in elv_complete_request() check whether
  the queue is empty.  Empty queue also indicates drain completion.

* While at it, convert 0/1 return from blk_do_ordered() to false/true.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:45 +01:00
Tejun Heo
f671620e7d block: make every barrier action optional
In all barrier sequences, the barrier write itself was always assumed
to be issued and thus didn't have corresponding control flag.  This
patch adds QUEUE_ORDERED_DO_BAR and unify action mask handling in
start_ordered() such that any barrier action can be skipped.

This patch doesn't introduce any visible behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:45 +01:00
Tejun Heo
313e42999d block: reorganize QUEUE_ORDERED_* constants
Separate out ordering type (drain,) and action masks (preflush,
postflush, fua) from visible ordering mode selectors
(QUEUE_ORDERED_*).  Ordering types are now named QUEUE_ORDERED_BY_*
while action masks are named QUEUE_ORDERED_DO_*.

This change is necessary to add QUEUE_ORDERED_DO_BAR and make it
optional to improve empty barrier implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:44 +01:00
Cheng Renquan
64d01dc9e1 block: use cancel_work_sync() instead of kblockd_flush_work()
After many improvements on kblockd_flush_work, it is now identical to
cancel_work_sync, so a direct call to cancel_work_sync is suggested.

The only difference is that cancel_work_sync is a GPL symbol,
so no non-GPL modules anymore.

Signed-off-by: Cheng Renquan <crquan@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:44 +01:00
Fernando Luis Vázquez Cao
88e740f165 block: add queue flag for paravirt frontend drivers
As is the case with SSD devices, we do not want to idle in AS/CFQ when
the block device is a paravirt front-end driver. This patch adds a flag
(QUEUE_FLAG_VIRT) which should be used by front-end drivers such as
virtio_blk and xen-blkfront to indicate a paravirtualized device.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:41 +01:00
Linus Torvalds
f2f1fa78a1 Enforce a minimum SG_IO timeout
There's no point in having too short SG_IO timeouts, since if the
command does end up timing out, we'll end up through the reset sequence
that is several seconds long in order to abort the command that timed
out.

As a result, shorter timeouts than a few seconds simply do not make
sense, as the recovery would be longer than the timeout itself.

Add a BLK_MIN_SG_TIMEOUT to match the existign BLK_DEFAULT_SG_TIMEOUT.

Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-05 14:49:18 -08:00
Milan Broz
0e435ac26e block: fix setting of max_segment_size and seg_boundary mask
Fix setting of max_segment_size and seg_boundary mask for stacked md/dm
devices.

When stacking devices (LVM over MD over SCSI) some of the request queue
parameters are not set up correctly in some cases by default, namely
max_segment_size and and seg_boundary mask.

If you create MD device over SCSI, these attributes are zeroed.

Problem become when there is over this mapping next device-mapper mapping
- queue attributes are set in DM this way:

request_queue   max_segment_size  seg_boundary_mask
SCSI                65536             0xffffffff
MD RAID1                0                      0
LVM                 65536                 -1 (64bit)

Unfortunately bio_add_page (resp.  bio_phys_segments) calculates number of
physical segments according to these parameters.

During the generic_make_request() is segment cout recalculated and can
increase bio->bi_phys_segments count over the allowed limit.  (After
bio_clone() in stack operation.)

Thi is specially problem in CCISS driver, where it produce OOPS here

    BUG_ON(creq->nr_phys_segments > MAXSGENTRIES);

(MAXSEGENTRIES is 31 by default.)

Sometimes even this command is enough to cause oops:

  dd iflag=direct if=/dev/<vg>/<lv> of=/dev/null bs=128000 count=10

This command generates bios with 250 sectors, allocated in 32 4k-pages
(last page uses only 1024 bytes).

For LVM layer, it allocates bio with 31 segments (still OK for CCISS),
unfortunatelly on lower layer it is recalculated to 32 segments and this
violates CCISS restriction and triggers BUG_ON().

The patch tries to fix it by:

 * initializing attributes above in queue request constructor
   blk_queue_make_request()

 * make sure that blk_queue_stack_limits() inherits setting

 (DM uses its own function to set the limits because it
 blk_queue_stack_limits() was introduced later.  It should probably switch
 to use generic stack limit function too.)

 * sets the default seg_boundary value in one place (blkdev.h)

 * use this mask as default in DM (instead of -1, which differs in 64bit)

Bugs related to this:
https://bugzilla.redhat.com/show_bug.cgi?id=471639
http://bugzilla.kernel.org/show_bug.cgi?id=8672

Signed-off-by: Milan Broz <mbroz@redhat.com>
Reviewed-by: Alasdair G Kergon <agk@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Mike Miller <mike.miller@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-03 12:55:55 +01:00
Tejun Heo
53a08807c0 block: internal dequeue shouldn't start timer
blkdev_dequeue_request() and elv_dequeue_request() are equivalent and
both start the timeout timer.  Barrier code dequeues the original
barrier request but doesn't passes the request itself to lower level
driver, only broken down proxy requests; however, as the original
barrier code goes through the same dequeue path and timeout timer is
started on it.  If barrier sequence takes long enough, this timer
expires but the low level driver has no idea about this request and
oops follows.

Timeout timer shouldn't have been started on the original barrier
request as it never goes through actual IO.  This patch unexports
elv_dequeue_request(), which has no external user anyway, and makes it
operate on elevator proper w/o adding the timer and make
blkdev_dequeue_request() call elv_dequeue_request() and add timer.
Internal users which don't pass the request to driver - barrier code
and end_that_request_last() - are converted to use
elv_dequeue_request().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-03 12:41:26 +01:00
Al Viro
90b8f2824c [PATCH] end of methods switch: remove the old ones
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:48:52 -04:00
Al Viro
d4430d62fa [PATCH] beginning of methods conversion
To keep the size of changesets sane we split the switch by drivers;
to keep the damn thing bisectable we do the following:
	1) rename the affected methods, add ones with correct
prototypes, make (few) callers handle both.  That's this changeset.
	2) for each driver convert to new methods.  *ALL* drivers
are converted in this series.
	3) kill the old (renamed) methods.

Note that it _is_ a flagday; all in-tree drivers are converted and by the
end of this series no trace of old methods remain.  The only reason why
we do that this way is to keep the damn thing bisectable and allow per-driver
debugging if anything goes wrong.

New methods:
	open(bdev, mode)
	release(disk, mode)
	ioctl(bdev, mode, cmd, arg)		/* Called without BKL */
	compat_ioctl(bdev, mode, cmd, arg)
	locked_ioctl(bdev, mode, cmd, arg)	/* Called with BKL, legacy */

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:32 -04:00
Al Viro
633a08b812 [PATCH] introduce __blkdev_driver_ioctl()
Analog of blkdev_driver_ioctl() with sane arguments.  For
now uses fake struct file, by the end of the series it won't
and blkdev_driver_ioctl() will become a wrapper around it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:26 -04:00
Al Viro
08f8585121 [PATCH] move block_device_operations to blkdev.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:20 -04:00
Al Viro
74f3c8aff3 [PATCH] switch scsi_cmd_ioctl() to passing fmode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:14 -04:00
Al Viro
e915e872ed [PATCH] switch sg_scsi_ioctl() to passing fmode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:12 -04:00
Al Viro
aeb5d72706 [PATCH] introduce fmode_t, do annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:06 -04:00
Linus Torvalds
c53dbf5486 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: remove __generic_unplug_device() from exports
  block: move q->unplug_work initialization
  blktrace: pass zfcp driver data
  blktrace: add support for driver data
  block: fix current kernel-doc warnings
  block: only call ->request_fn when the queue is not stopped
  block: simplify string handling in elv_iosched_store()
  block: fix kernel-doc for blk_alloc_devt()
  block: fix nr_phys_segments miscalculation bug
  block: add partition attribute for partition number
  block: add BIG FAT WARNING to CONFIG_DEBUG_BLOCK_EXT_DEVT
  softirq: Add support for triggering softirq work on softirqs.
2008-10-17 09:29:55 -07:00
Jens Axboe
f73e2d13a1 block: remove __generic_unplug_device() from exports
The only out-of-core user is IDE, and that should be using
blk_start_queueing() instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-17 14:03:08 +02:00
Mike Christie
6000a368cd [SCSI] block: separate failfast into multiple bits.
Multipath is best at handling transport errors. If it gets a device
error then there is not much the multipath layer can do. It will just
access the same device but from a different path.

This patch breaks up failfast into device, transport and driver errors.
The multipath layers (md and dm mutlipath) only ask the lower levels to
fast fail transport errors. The user of failfast, read ahead, will ask
to fast fail on all errors.

Note that blk_noretry_request will return true if any failfast bit
is set. This allows drivers that do not support the multipath failfast
bits to continue to fail on any failfast error like before. Drivers
like scsi that are able to fail fast specific errors can check
for the specific fail fast type. In the next patch I will convert
scsi.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:52 -04:00
Martin K. Petersen
b02739b01c block: gendisk integrity wrapper
This is a wrapper for accessing a gendisk's integrity bits.  It allows
the integrity support in MD to be compiled with BLK_DEV_INTEGRITY off.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:22 +02:00
Martin K. Petersen
ad7fce9314 block: Switch blk_integrity_compare from bdev to gendisk
The DM and MD integrity support now depends on being able to use
gendisks instead of block_devices when comparing integrity profiles.
Change function parameters accordingly.

Also update comparison logic so that two NULL profiles are a valid
configuration.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:21 +02:00
Jens Axboe
b04accc425 block: revert part of d7533ad0e132f92e75c1b2eb7c26387b25a583c1
We need bdev_get_integrity() to support the pending md/dm patches.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:21 +02:00
Kiyoshi Ueda
d00e29fd99 block: remove end_{queued|dequeued}_request()
This patch removes end_queued_request() and end_dequeued_request(),
which are no longer used.

As a results, users of __end_request() became only end_request().
So the actual code in __end_request() is moved to end_request()
and __end_request() is removed.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:21 +02:00
Kiyoshi Ueda
ef9e3facdf block: add lld busy state exporting interface
This patch adds an new interface, blk_lld_busy(), to check lld's
busy state from the block layer.
blk_lld_busy() calls down into low-level drivers for the checking
if the drivers set q->lld_busy_fn() using blk_queue_lld_busy().

This resolves a performance problem on request stacking devices below.

Some drivers like scsi mid layer stop dispatching request when
they detect busy state on its low-level device like host/target/device.
It allows other requests to stay in the I/O scheduler's queue
for a chance of merging.

Request stacking drivers like request-based dm should follow
the same logic.
However, there is no generic interface for the stacked device
to check if the underlying device(s) are busy.
If the request stacking driver dispatches and submits requests to
the busy underlying device, the requests will stay in
the underlying device's queue without a chance of merging.
This causes performance problem on burst I/O load.

With this patch, busy state of the underlying device is exported
via q->lld_busy_fn().  So the request stacking driver can check it
and stop dispatching requests if busy.

The underlying device driver must return the busy state appropriately:
    1: when the device driver can't process requests immediately.
    0: when the device driver can process requests immediately,
       including abnormal situations where the device driver needs
       to kill all requests.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:20 +02:00
Jens Axboe
a68bbddba4 block: add queue flag for SSD/non-rotational devices
We don't want to idle in AS/CFQ if the device doesn't have a seek
penalty. So add a QUEUE_FLAG_NONROT to indicate a non-rotational
device, low level drivers should set this flag upon discovery of
an SSD or similar device type.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:19 +02:00
Kiyoshi Ueda
4ee5eaf451 block: add a queue flag for request stacking support
This patch adds a queue flag to indicate the block device can be
used for request stacking.

Request stacking drivers need to stack their devices on top of
only devices of which q->request_fn is functional.
Since bio stacking drivers (e.g. md, loop) basically initialize
their queue using blk_alloc_queue() and don't set q->request_fn,
the check of (q->request_fn == NULL) looks enough for that purpose.

However, dm will become both types of stacking driver (bio-based and
request-based).  And dm will always set q->request_fn even if the dm
device is bio-based of which q->request_fn is not functional actually.
So we need something else to distinguish the type of the device.
Adding a queue flag is a solution for that.

The reason why dm always sets q->request_fn is to keep
the compatibility of dm user-space tools.
Currently, all dm user-space tools are using bio-based dm without
specifying the type of the dm device they use.
To use request-based dm without changing such tools, the kernel
must decide the type of the dm device automatically.
The automatic type decision can't be done at the device creation time
and needs to be deferred until such tools load a mapping table,
since the actual type is decided by dm target type included in
the mapping table.

So a dm device has to be initialized using blk_init_queue()
so that we can load either type of table.
Then, all queue stuffs are set (e.g. q->request_fn) and we have
no element to distinguish that it is bio-based or request-based,
even after a table is loaded and the type of the device is decided.

By the way, some stuffs of the queue (e.g. request_list, elevator)
are needless when the dm device is used as bio-based.
But the memory size is not so large (about 20[KB] per queue on ia64),
so I hope the memory loss can be acceptable for bio-based dm users.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:18 +02:00
Kiyoshi Ueda
82124d6035 block: add request submission interface
This patch adds blk_insert_cloned_request(), a generic request
submission interface for request stacking drivers.
Request-based dm will use it to submit their clones to underlying
devices.

blk_rq_check_limits() is also added because it is possible that
the lower queue has stronger limitations than the upper queue
if multiple drivers are stacking at request-level.
Not only for blk_insert_cloned_request()'s internal use, the function
will be used by request-based dm when the queue limitation is
modified (e.g. by replacing dm's table).

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:18 +02:00
Kiyoshi Ueda
32fab448e5 block: add request update interface
This patch adds blk_update_request(), which updates struct request
with completing its data part, but doesn't complete the struct
request itself.
Though it looks like end_that_request_first() of older kernels,
blk_update_request() should be used only by request stacking drivers.

Request-based dm will use it in bio->bi_end_io callback to update
the original request when a data part of a cloned request completes.
Followings are additional background information of why request-based
dm needs this interface.

  - Request stacking drivers can't use blk_end_request() directly from
    the lower driver's completion context (bio->bi_end_io or rq->end_io),
    because some device drivers (e.g. ide) may try to complete
    their request with queue lock held, and it may cause deadlock.
    See below for detailed description of possible deadlock:
    <http://marc.info/?l=linux-kernel&m=120311479108569&w=2>

  - To solve that, request-based dm offloads the completion of
    cloned struct request to softirq context (i.e. using
    blk_complete_request() from rq->end_io).

  - Though it is possible to use the same solution from bio->bi_end_io,
    it will delay the notification of bio completion to the original
    submitter.  Also, it will cause inefficient partial completion,
    because the lower driver can't perform the cloned request anymore
    and request-based dm needs to requeue and redispatch it to
    the lower driver again later.  That's not good.

  - So request-based dm needs blk_update_request() to perform the bio
    completion in the lower driver's completion context, which is more
    efficient.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:18 +02:00
Jens Axboe
9c02f2b02e block: cleanup some of the integrity stuff in blkdev.h
Don't put functions that are only used in fs/bio-integrity.c in
blkdev.h, it's much cleaner to just keep it in there. Also kill
completely unused bdev_get_tag_size()

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:17 +02:00
Jens Axboe
581d4e28d9 block: add fault injection mechanism for faking request timeouts
Only works for the generic request timer handling. Allows one to
sporadically ignore request completions, thus exercising the timeout
handling.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:17 +02:00
Hugh Dickins
3e6053d76d block: adjust blkdev_issue_discard for swap
Two mods to blkdev_issue_discard(), thinking ahead to its use on swap:

1. Add gfp_mask argument, so swap allocation can use it where GFP_KERNEL
   might deadlock but GFP_NOIO is safe.

2. Enlarge nr_sects argument from unsigned to sector_t: unsigned long is
   enough to cover a whole swap area, but sector_t suits any partition.

Change sb_issue_discard()'s nr_blocks to sector_t too; but no need seen
for a gfp_mask there, just pass GFP_KERNEL down to blkdev_issue_discard().

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:17 +02:00
Mike Anderson
11914a53d2 block: Add interface to abort queued requests
Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:13 +02:00
Jens Axboe
242f9dcb8b block: unify request timeout handling
Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:13 +02:00
FUJITA Tomonori
879040742c block: add blk_rq_aligned helper function
This adds blk_rq_aligned helper function to see if alignment and
padding requirement is satisfied for DMA transfer. This also converts
blk_rq_map_kern and __blk_rq_map_user to use the helper function.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:11 +02:00
FUJITA Tomonori
152e283fdf block: introduce struct rq_map_data to use reserved pages
This patch introduces struct rq_map_data to enable bio_copy_use_iov()
use reserved pages.

Currently, bio_copy_user_iov allocates bounce pages but
drivers/scsi/sg.c wants to allocate pages by itself and use
them. struct rq_map_data can be used to pass allocated pages to
bio_copy_user_iov.

The current users of bio_copy_user_iov simply passes NULL (they don't
want to use pre-allocated pages).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:10 +02:00
FUJITA Tomonori
a3bce90edd block: add gfp_mask argument to blk_rq_map_user and blk_rq_map_user_iov
Currently, blk_rq_map_user and blk_rq_map_user_iov always do
GFP_KERNEL allocation.

This adds gfp_mask argument to blk_rq_map_user and blk_rq_map_user_iov
so sg can use it (sg always does GFP_ATOMIC allocation).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Douglas Gilbert <dougg@torque.net>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:10 +02:00
Jens Axboe
ab780f1ece block: inherit CPU completion on bio->rq and rq->rq merges
Somewhat incomplete, as we do allow merges of requests and bios
that have different completion CPUs given. This is done on the
assumption that a larger IO is still more beneficial than CPU
locality.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:09 +02:00
Jens Axboe
c7c22e4d5c block: add support for IO CPU affinity
This patch adds support for controlling the IO completion CPU of
either all requests on a queue, or on a per-request basis. We export
a sysfs variable (rq_affinity) which, if set, migrates completions
of requests to the CPU that originally submitted it. A bio helper
(bio_set_completion_cpu()) is also added, so that queuers can ask
for completion on that specific CPU.

In testing, this has been show to cut the system time by as much
as 20-40% on synthetic workloads where CPU affinity is desired.

This requires a little help from the architecture, so it'll only
work as designed for archs that are using the new generic smp
helper infrastructure.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:09 +02:00
Jens Axboe
18887ad910 block: make kblockd_schedule_work() take the queue as parameter
Preparatory patch for checking queuing affinity.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:09 +02:00
Mikulas Patocka
5df97b91b5 drop vmerge accounting
Remove hw_segments field from struct bio and struct request. Without virtual
merge accounting they have no purpose.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:03 +02:00
Fernando Luis Vázquez Cao
766ca4428d virtio_blk: use a wrapper function to access io context information of IO requests
struct request has an ioprio member but it is never updated because
currently bios do not hold io context information. The implication of
this is that virtio_blk ends up passing useless information to the
backend driver.

That said, some IO schedulers such as CFQ do store io context
information in struct request, but use private members for that, which
means that that information cannot be directly accessed in a IO
scheduler-independent way.

This patch adds a function to obtain the ioprio of a request. We should
avoid accessing ioprio directly and use this function instead, so that
its users do not have to care about future changes in block layer
structures or what the currently active IO controller is.

This patch does not introduce any functional changes but paves the way
for future clean-ups and enhancements.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:02 +02:00
David Woodhouse
1a8e2bddd5 Kill REQ_TYPE_FLUSH
It was only used by ps3disk, and it should probably have been
REQ_TYPE_LINUX_BLOCK + REQ_LB_OP_FLUSH.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:02 +02:00
David Woodhouse
e17fc0a1cc Allow elevators to sort/merge discard requests
But blkdev_issue_discard() still emits requests which are interpreted as
soft barriers, because naïve callers might otherwise issue subsequent
writes to those same sectors, which might cross on the queue (if they're
reallocated quickly enough).

Callers still _can_ issue non-barrier discard requests, but they have to
take care of queue ordering for themselves.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:02 +02:00
David Woodhouse
eae9acd13a Support 'discard sectors' operation in translation layer support core
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:01 +02:00
David Woodhouse
fb2dce862d Add 'discard' request handling
Some block devices benefit from a hint that they can forget the contents
of certain sectors. Add basic support for this to the block core, along
with a 'blkdev_issue_discard()' helper function which issues such
requests.

The caller doesn't get to provide an end_io functio, since
blkdev_issue_discard() will automatically split the request up into
multiple bios if appropriate. Neither does the function wait for
completion -- it's expected that callers won't care about when, or even
_if_, the request completes. It's only a hint to the device anyway. By
definition, the file system doesn't _care_ about these sectors any more.

[With feedback from OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> and
Jens Axboe <jens.axboe@oracle.com]

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:01 +02:00
David Woodhouse
d628eaef31 Fix up comments about matching flags between bio and rq
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:01 +02:00
Jens Axboe
2dc75d3c3b block: disable sysfs parts of the disk command filter
We still have life time issues with the sysfs command filter kobject,
so disable it for 2.6.27 release. We can revisit this and make it work
properly for 2.6.28, for 2.6.27 release it's too risky.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-09-11 14:20:23 +02:00
Jens Axboe
5168c47b4c block: remove blk_queue_tag_depth() and blk_queue_tag_queue()
They are unused and ->busy doesn't exist anymore.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-27 09:50:20 +02:00
FUJITA Tomonori
4beab5c623 block: rename blk_scsi_cmd_filter to blk_cmd_filter
Technically, the cmd_filter would be applied to other protocols though
it's unlikely to happen. Putting SCSI stuff to request_queue is kinda
layer violation. So let's rename it.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-27 09:50:19 +02:00
FUJITA Tomonori
abf5439370 block: move cmdfilter from gendisk to request_queue
cmd_filter works only for the block layer SG_IO with SCSI block
devices. It breaks scsi/sg.c, bsg, and the block layer SG_IO with SCSI
character devices (such as st). We hit a kernel crash with them.

The problem is that cmd_filter code accesses to gendisk (having struct
blk_scsi_cmd_filter) via inode->i_bdev->bd_disk. It works for only
SCSI block device files. With character device files, inode->i_bdev
leads you to struct cdev. inode->i_bdev->bd_disk->blk_scsi_cmd_filter
isn't safe.

SCSI ULDs don't expose gendisk; they keep it private. bsg needs to be
independent on any protocols. We shouldn't change ULDs to expose their
gendisk.

This patch moves struct blk_scsi_cmd_filter from gendisk to
request_queue, a common object, which eveyone can access to.

The user interface doesn't change; users can change the filters via
/sys/block/. gendisk has a pointer to request_queue so the cmd_filter
code accesses to struct blk_scsi_cmd_filter.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-27 09:50:19 +02:00
Jens Axboe
6c5e0c4d51 block: add a blk_plug_device_unlocked() that grabs the queue lock
blk_plug_device() must be called with the queue lock held, so callers
often just grab and release the lock for that purpose. Add a helper
that does just that.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-01 20:31:32 +02:00
Martin K. Petersen
d442cc44c0 block: Trivial fix for blk_integrity_rq()
Fail integrity check gracefully when request does not have a bio
attached (BLOCK_PC).

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-16 14:51:41 -07:00
Linus Torvalds
98339cbd36 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6: (80 commits)
  ide-floppy: fix unfortunate function naming
  ide-tape: unify idetape_create_read/write_cmd
  ide: add ide_pc_intr() helper
  ide-{floppy,scsi}: read Status Register before stopping DMA engine
  ide-scsi: add more debugging to idescsi_pc_intr()
  ide-scsi: use pc->callback
  ide-floppy: add more debugging to idefloppy_pc_intr()
  ide-tape: always log debug info in idetape_pc_intr() if debugging is enabled
  ide-tape: add ide_tape_io_buffers() helper
  ide-tape: factor out DSC handling from idetape_pc_intr()
  ide-{floppy,tape}: move checking of ->failed_pc to ->callback
  ide: add ide_issue_pc() helper
  ide: add PC_FLAG_DRQ_INTERRUPT pc flag
  ide-scsi: move idescsi_map_sg() call out from idescsi_issue_pc()
  ide: add ide_transfer_pc() helper
  ide-scsi: set drive->scsi flag for devices handled by the driver
  ide-{cd,floppy,tape}: remove checking for drive->scsi
  ide: add PC_FLAG_ZIP_DRIVE pc flag
  ide-tape: factor out waiting for good ireason from idetape_transfer_pc()
  ide-tape: set PC_FLAG_DMA_IN_PROGRESS flag in idetape_transfer_pc()
  ...
2008-07-15 11:15:36 -07:00
FUJITA Tomonori
681a561b7e block: unexport blk_end_sync_rq
All the users of blk_end_sync_rq has gone (they are converted to use
blk_execute_rq). This unexports blk_end_sync_rq.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-07-15 21:21:45 +02:00
FUJITA Tomonori
27f8221af4 block: add blk_queue_update_dma_pad
This adds blk_queue_update_dma_pad to prevent LLDs from overwriting
the dma pad mask wrongly (we added blk_queue_update_dma_alignment due
to the same reason).

This also converts libata to use blk_queue_update_dma_pad instead of
blk_queue_dma_pad.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-04 09:52:13 +02:00
Jens Axboe
e48ec69005 block: extend queue_flag bitops
Add test_and_clear and test_and_set.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:15 +02:00
Alasdair G Kergon
cc371e66e3 Add bvec_merge_data to handle stacked devices and ->merge_bvec()
When devices are stacked, one device's merge_bvec_fn may need to perform
the mapping and then call one or more functions for its underlying devices.

The following bio fields are used:
  bio->bi_sector
  bio->bi_bdev
  bio->bi_size
  bio->bi_rw  using bio_data_dir()

This patch creates a new struct bvec_merge_data holding a copy of those
fields to avoid having to change them directly in the struct bio when
going down the stack only to have to change them back again on the way
back up.  (And then when the bio gets mapped for real, the whole
exercise gets repeated, but that's a problem for another day...)

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:15 +02:00
Jens Axboe
b24498d477 block: integrity flags can't use bit ops on unsigned short
Just use normal open coded bit operations instead, they need not be
atomic.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:15 +02:00
Adel Gadllah
0b07de85a7 allow userspace to modify scsi command filter on per device basis
This patch exports the per-gendisk command filter to user space through
sysfs, so it can be changed by the system administrator.
All users of the old cmd filter have been converted to use the new one.

Original patch from Peter Jones.

Signed-off-by: Adel Gadllah <adel.gadllah@gmail.com>
Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:14 +02:00
Jens Axboe
6e2401ad6f block: integrity cleanups
- No need to check for NULL bio, we'll get an immediate oops anyway.
- Make bio_integrity() a proper function.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:14 +02:00
Jens Axboe
da9cbc8739 block: blkdev.h cleanup, move iocontext stuff to iocontext.h
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:14 +02:00
Martin K. Petersen
7ba1ba12ee block: Block layer data integrity support
Some block devices support verifying the integrity of requests by way
of checksums or other protection information that is submitted along
with the I/O.

This patch implements support for generating and verifying integrity
metadata, as well as correctly merging, splitting and cloning bios and
requests that have this extra information attached.

See Documentation/block/data-integrity.txt for more information.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:13 +02:00
Jens Axboe
244b4d56f8 block: kill request_queue_t
Everything was moved to struct request_queue a few kernel revisions
ago, maintaining the deprecated typedef to avoid breaking things.
Now the time has come to get rid of that typedef.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:12 +02:00
Jens Axboe
7663c1e279 Improve queue_is_locked()
spin_is_locked() doesn't work on UP without spinlock debugging. Make it
safer and just return 1 on UP, so we don't get false positives. The plan
is to kill this debug function during the -rc cycle.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 12:36:54 -07:00
Linus Torvalds
8f45c1a58a block: fix queue locking verification
The new queue_flag_set/clear() functions verify that the queue is
locked, but in doing so they will actually instead oops if the queue
lock hasn't been initialized at all.

So fix the lock debug test to consider the "no lock" case to be
unlocked.  This way you get a nice WARN_ON_ONCE() instead of a fatal
oops.

Bug introduced by commit 75ad23bc0f
("block: make queue flags non-atomic").

Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 10:16:38 -07:00
Alan D. Brunelle
ac9fafa124 block: Skip I/O merges when disabled
The block I/O + elevator + I/O scheduler code spend a lot of time trying
to merge I/Os -- rightfully so under "normal" circumstances. However,
if one were to know that the incoming I/O stream was /very/ random in
nature, the cycles are wasted.

This patch adds a per-request_queue tunable that (when set) disables
merge attempts (beyond the simple one-hit cache check), thus freeing up
a non-trivial amount of CPU cycles.

Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:55 +02:00
FUJITA Tomonori
d7e3c3249e block: add large command support
This patch changes rq->cmd from the static array to a pointer to
support large commands.

We rarely handle large commands. So for optimization, a struct request
still has a static array for a command. rq_init sets rq->cmd pointer
to the static array.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:55 +02:00
FUJITA Tomonori
2a4aa30c5f block: rename and export rq_init()
This rename rq_init() blk_rq_init() and export it. Any path that hands
the request to the block layer needs to call it to initialize the
request.

This is a preparation for large command support, which needs to
initialize the request in a proper way (that is, just doing a memset()
will not work).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:55 +02:00
Nick Piggin
75ad23bc0f block: make queue flags non-atomic
We can save some atomic ops in the IO path, if we clearly define
the rules of how to modify the queue flags.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:33 +02:00
Andi Kleen
2472892a3c block: fix memory hotplug and bouncing in block layer
Only noticed this while hacking something else, no test case.

blk_max_low_pfn is initialized once at bootup by the block layer from
max_low_pfn.  But max_low_pfn is not necessarily constant over the runtime of
the system when you consider memory hotplug.  What could happen if that
someone adds memory later the block layer wouldn't get updated and then start
bouncing memory unnecessarily.

Also on 64bit blk_max_low_pfn actually isn't needed because it just disables
bouncing essentially and there is no highmem.  And nobody can pass pfns >
max_low_pfn to the block layer, because those wouldn't have a struct page and
I suspect block layer wouldn't be very happy without that.

So set BLK_BOUNCE_HIGH to infinity (-1ULL) on 64bit.  That avoids the problem
of having to update it on memory hotadd.

On 32bit I kept the same behaviour because at least on i386
memory hotadd only adds HIGHMEM, never lowmem.

BLK_BOUNCE_ANY is always set to infinity on both 32 and 64bit.

Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-21 09:51:05 +02:00
FUJITA Tomonori
f18573abcc block: move the padding adjustment to blk_rq_map_sg
blk_rq_map_user adjusts bi_size of the last bio. It breaks the rule
that req->data_len (the true data length) is equal to sum(bio). It
broke the scsi command completion code.

commit e97a294ef6 was introduced to fix
the above issue. However, the partial completion code doesn't work
with it. The commit is also a layer violation (scsi mid-layer should
not know about the block layer's padding).

This patch moves the padding adjustment to blk_rq_map_sg (suggested by
James). The padding works like the drain buffer. This patch breaks the
rule that req->data_len is equal to sum(sg), however, the drain buffer
already broke it. So this patch just restores the rule that
req->data_len is equal to sub(bio) without breaking anything new.

Now when a low level driver needs padding, blk_rq_map_user and
blk_rq_map_user_iov guarantee there's enough room for padding.
blk_rq_map_sg can safely extend the last entry of a scatter list.

blk_rq_map_sg must extend the last entry of a scatter list only for a
request that got through bio_copy_user_iov. This patches introduces
new REQ_COPY_USER flag.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-21 09:50:08 +02:00
Tejun Heo
e3790c7d42 block: separate out padding from alignment
Block layer alignment was used for two different purposes - memory
alignment and padding.  This causes problems in lower layers because
drivers which only require memory alignment ends up with adjusted
rq->data_len.  Separate out padding such that padding occurs iff
driver explicitly requests it.

Tomo: restorethe code to update bio in blk_rq_map_user
      introduced by the commit 40b01b9bbd
      according to padding alignment.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:18:17 +01:00
FUJITA Tomonori
7a85f8896f block: restore the meaning of rq->data_len to the true data length
The meaning of rq->data_len was changed to the length of an allocated
buffer from the true data length. It breaks SG_IO friends and
bsg. This patch restores the meaning of rq->data_len to the true data
length and adds rq->extra_len to store an extended length (due to
drain buffer and padding).

This patch also removes the code to update bio in blk_rq_map_user
introduced by the commit 40b01b9bbd.
The commit adjusts bio according to memory alignment
(queue_dma_alignment). However, memory alignment is NOT padding
alignment. This adjustment also breaks SG_IO friends and bsg. Padding
alignment needs to be fixed in a proper way (by a separate patch).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
2008-03-04 11:17:11 +01:00
Tejun Heo
2fb98e8414 block: implement request_queue->dma_drain_needed
Draining shouldn't be done for commands where overflow may indicate
data integrity issues.  Add dma_drain_needed callback to
request_queue.  Drain buffer is appened iff this function returns
non-zero.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:36:53 +01:00
Tejun Heo
6b00769fe1 block: add request->raw_data_len
With padding and draining moved into it, block layer now may extend
requests as directed by queue parameters, so now a request has two
sizes - the original request size and the extended size which matches
the size of area pointed to by bios and later by sgs.  The latter size
is what lower layers are primarily interested in when allocating,
filling up DMA tables and setting up the controller.

Both padding and draining extend the data area to accomodate
controller characteristics.  As any controller which speaks SCSI can
handle underflows, feeding larger data area is safe.

So, this patch makes the primary data length field, request->data_len,
indicate the size of full data area and add a separate length field,
request->raw_data_len, for the unmodified request size.  The latter is
used to report to higher layer (userland) and where the original
request size should be fed to the controller or device.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:36:35 +01:00
Jens Axboe
63a7138671 block: fixup rq_init() a bit
Rearrange fields in cache order and initialize some fields that
we didn't previously init. Remove init of ->completion_data, it's
part of a union with ->hash. Luckily clearing the rb node is the same
as setting it to null!

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-08 12:41:03 +01:00
Jens Axboe
3bc217ffe6 block: kill swap_io_context()
It blindly copies everything in the io_context, including the lock.
That doesn't work so well for either lock ordering or lockdep.

There seems zero point in swapping io contexts on a request to request
merge, so the best point of action is to just remove it.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-01 11:34:49 +01:00
Jens Axboe
22b132102f block: new end request handling interface should take unsigned byte counts
No point in passing signed integers as the byte count, they can never
be negative.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-01 09:26:33 +01:00
Jens Axboe
023ccde109 block: fix warning on compile with CONFIG_BLOCK
struct io_context was not defined, just add an empty forward decl.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:14 +01:00
Linus Torvalds
8d01eddf29 Merge branch 'for-2.6.25' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.25' of git://git.kernel.dk/linux-2.6-block:
  block: implement drain buffers
  __bio_clone: don't calculate hw/phys segment counts
  block: allow queue dma_alignment of zero
  blktrace: Add blktrace ioctls to SCSI generic devices
2008-01-29 08:51:56 +11:00
Linus Torvalds
f0f0052069 Merge branch 'blk-end-request' of git://git.kernel.dk/linux-2.6-block
* 'blk-end-request' of git://git.kernel.dk/linux-2.6-block: (30 commits)
  blk_end_request: changing xsysace (take 4)
  blk_end_request: changing ub (take 4)
  blk_end_request: cleanup of request completion (take 4)
  blk_end_request: cleanup 'uptodate' related code (take 4)
  blk_end_request: remove/unexport end_that_request_* (take 4)
  blk_end_request: changing scsi (take 4)
  blk_end_request: add bidi completion interface (take 4)
  blk_end_request: changing ide-cd (take 4)
  blk_end_request: add callback feature (take 4)
  blk_end_request: changing ide normal caller (take 4)
  blk_end_request: changing cpqarray (take 4)
  blk_end_request: changing cciss (take 4)
  blk_end_request: changing ide-scsi (take 4)
  blk_end_request: changing s390 (take 4)
  blk_end_request: changing mmc (take 4)
  blk_end_request: changing i2o_block (take 4)
  blk_end_request: changing viocd (take 4)
  blk_end_request: changing xen-blkfront (take 4)
  blk_end_request: changing viodasd (take 4)
  blk_end_request: changing sx8 (take 4)
  ...
2008-01-29 08:51:32 +11:00
James Bottomley
fa0ccd837e block: implement drain buffers
These DMA drain buffer implementations in drivers are pretty horrible
to do in terms of manipulating the scatterlist.  Plus they're being
done at least in drivers/ide and drivers/ata, so we now have code
duplication.

The one use case for this, as I understand it is AHCI controllers doing
PIO mode to mmc devices but translating this to DMA at the controller
level.

So, what about adding a callback to the block layer that permits the
adding of the drain buffer for the problem devices.  The idea is that
you'd do this in slave_configure after you find one of these devices.

The beauty of doing it in the block layer is that it quietly adds the
drain buffer to the end of the sg list, so it automatically gets mapped
(and unmapped) without anything unusual having to be done to the
scatterlist in driver/scsi or drivers/ata and without any alteration to
the transfer length.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:54:11 +01:00
Jens Axboe
d38ecf935f io context sharing: preliminary support
Detach task state from ioc, instead keep track of how many processes
are accessing the ioc.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:50:31 +01:00
Jens Axboe
fd0928df98 ioprio: move io priority from task_struct to io_context
This is where it belongs and then it doesn't take up space for a
process that doesn't do IO.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:50:29 +01:00
Kiyoshi Ueda
5450d3e1d6 blk_end_request: cleanup 'uptodate' related code (take 4)
This patch converts 'uptodate' arguments of no longer exported
interfaces, end_that_request_first/last, to 'error', and removes
internal conversions for it in blk_end_request interfaces.

Also, this patch removes no longer needed end_io_error().

Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:37:13 +01:00
Kiyoshi Ueda
3bcddeac1c blk_end_request: remove/unexport end_that_request_* (take 4)
This patch removes the following functions:
  o end_that_request_first()
  o end_that_request_chunk()
and stops exporting the functions below:
  o end_that_request_last()

Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:37:12 +01:00
Kiyoshi Ueda
e3a04fe34a blk_end_request: add bidi completion interface (take 4)
This patch adds a variant of the interface, blk_end_bidi_request(),
which completes a bidi request.

Bidi request must be completed as a whole, both rq and rq->next_rq
at once.  So the interface has 2 arguments for completion size.

As for ->end_io, only rq->end_io is called (rq->next_rq->end_io is not
called).  So if special completion handling is needed, the handler
must be set to rq->end_io.
And the handler must take care of freeing next_rq too, since
the interface doesn't care of it if rq->end_io is not NULL.

Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:37:08 +01:00
Kiyoshi Ueda
e19a3ab058 blk_end_request: add callback feature (take 4)
This patch adds a variant of the interface, blk_end_request_callback(),
which has driver callback feature.

Drivers may need to do special works between end_that_request_first()
and end_that_request_last().
For such drivers, blk_end_request_callback() allows it to pass
a callback function which is called between end_that_request_first()
and end_that_request_last().

This interface is only for fallback of other blk_end_request interfaces.
Drivers should avoid their tricky behaviors and use other interfaces
as much as possible.

Currently, only one driver, ide-cd, needs this interface.
So this interface should/will be removed, after the driver removes
such tricky behaviors.

o ide-cd (cdrom_newpc_intr())
  In PIO mode, cdrom_newpc_intr() needs to defer end_that_request_last()
  until the device clears DRQ_STAT and raises an interrupt after
  end_that_request_first().
  So end_that_request_first() and end_that_request_last() are called
  separately in cdrom_newpc_intr().

  This means blk_end_request_callback() has to return without
  completing request even if no leftover in the request.
  To satisfy the requirement, callback function has return value
  so that drivers can tell blk_end_request_callback() to return
  without completing request.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:37:04 +01:00
Kiyoshi Ueda
3b11313a6c blk_end_request: add/export functions to get request size (take 4)
This patch adds/exports functions to get the size of request in bytes.
They are useful because blk_end_request interfaces take bytes
as a completed I/O size instead of sectors.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:35:56 +01:00
Kiyoshi Ueda
336cdb4003 blk_end_request: add new request completion interface (take 4)
This patch adds 2 new interfaces for request completion:
  o blk_end_request()   : called without queue lock
  o __blk_end_request() : called with queue lock held

blk_end_request takes 'error' as an argument instead of 'uptodate',
which current end_that_request_* take.
The meanings of values are below and the value is used when bio is
completed.
    0 : success
  < 0 : error

Some device drivers call some generic functions below between
end_that_request_{first/chunk} and end_that_request_last().
  o add_disk_randomness()
  o blk_queue_end_tag()
  o blkdev_dequeue_request()
These are called in the blk_end_request interfaces as a part of
generic request completion.
So all device drivers become to call above functions.
To decide whether to call blkdev_dequeue_request(), blk_end_request
uses list_empty(&rq->queuelist) (blk_queued_rq() macro is added for it).
So drivers must re-initialize it using list_init() or so before calling
blk_end_request if drivers use it for its specific purpose.
(Currently, there is no driver which completes request without
 re-initializing the queuelist after used it.  So rq->queuelist
 can be used for the purpose above.)

"Normal" drivers can be converted to use blk_end_request()
in a standard way shown below.

 a) end_that_request_{chunk/first}
    spin_lock_irqsave()
    (add_disk_randomness(), blk_queue_end_tag(), blkdev_dequeue_request())
    end_that_request_last()
    spin_unlock_irqrestore()
    => blk_end_request()

 b) spin_lock_irqsave()
    end_that_request_{chunk/first}
    (add_disk_randomness(), blk_queue_end_tag(), blkdev_dequeue_request())
    end_that_request_last()
    spin_unlock_irqrestore()
    => spin_lock_irqsave()
       __blk_end_request()
       spin_unlock_irqsave()

 c) spin_lock_irqsave()
    (add_disk_randomness(), blk_queue_end_tag(), blkdev_dequeue_request())
    end_that_request_last()
    spin_unlock_irqrestore()
    => blk_end_request()   or   spin_lock_irqsave()
                                __blk_end_request()
                                spin_unlock_irqrestore()

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:35:53 +01:00
Pete Wyckoff
482eb68916 block: allow queue dma_alignment of zero
Let queue_dma_alignment return 0 if it was specifically set to 0.
This permits devices with no particular alignment restrictions to
use arbitrary user space buffers without copying.

Signed-off-by: Pete Wyckoff <pw@osc.edu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:04:46 +01:00
Bartlomiej Zolnierkiewicz
7267c33774 ide: remove REQ_TYPE_ATA_CMD
Based on the earlier work by Tejun Heo.

All users are gone so we can finally remove it.

Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-01-26 20:13:13 +01:00
Linus Torvalds
9b73e76f3c Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (200 commits)
  [SCSI] usbstorage: use last_sector_bug flag universally
  [SCSI] libsas: abstract STP task status into a function
  [SCSI] ultrastor: clean up inline asm warnings
  [SCSI] aic7xxx: fix firmware build
  [SCSI] aacraid: fib context lock for management ioctls
  [SCSI] ch: remove forward declarations
  [SCSI] ch: fix device minor number management bug
  [SCSI] ch: handle class_device_create failure properly
  [SCSI] NCR5380: fix section mismatch
  [SCSI] sg: fix /proc/scsi/sg/devices when no SCSI devices
  [SCSI] IB/iSER: add logical unit reset support
  [SCSI] don't use __GFP_DMA for sense buffers if not required
  [SCSI] use dynamically allocated sense buffer
  [SCSI] scsi.h: add macro for enclosure bit of inquiry data
  [SCSI] sd: add fix for devices with last sector access problems
  [SCSI] fix pcmcia compile problem
  [SCSI] aacraid: add Voodoo Lite class of cards.
  [SCSI] aacraid: add new driver features flags
  [SCSI] qla2xxx: Update version number to 8.02.00-k7.
  [SCSI] qla2xxx: Issue correct MBC_INITIALIZE_FIRMWARE command.
  ...
2008-01-25 17:19:08 -08:00
Bartlomiej Zolnierkiewicz
29ed2a5f8c ide: remove REQ_TYPE_ATA_TASK
Based on the earlier work by Tejun Heo.

All users are gone so we can finally remove it.

Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-01-25 22:17:11 +01:00
James Bottomley
11c3e689f1 [SCSI] block: Introduce new blk_queue_update_dma_alignment interface
The purpose of this is to allow stacked alignment settings, with the
ultimate queue alignment being set to the largest alignment requirement
in the stack.

The reason for this is so that the SCSI mid-layer can relax the default
alignment requirements (which are basically causing a lot of superfluous
copying to go on in the SG_IO interface) while allowing transports,
devices or HBAs to add stricter limits if they need them.

Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:29:20 -06:00
Alan D. Brunelle
2ad8b1ef11 Add UNPLUG traces to all appropriate places
Added blk_unplug interface, allowing all invocations of unplugs to result
in a generated blktrace UNPLUG.

Signed-off-by: Alan D. Brunelle <Alan.Brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-11-09 13:41:32 +01:00
Jens Axboe
6eca9004df [BLOCK] Fix bad sharing of tag busy list on queues with shared tag maps
For the locking to work, only the tag map and tag bit map may be shared
(incidentally, I was just explaining this to Nick yesterday, but I
apparently didn't review the code well enough myself). But we also share
the busy list!  The busy_list must be queue private, or we need a
block_queue_tag covering lock as well.

So we have to move the busy_list to the queue. This'll work fine, and
it'll actually also fix a problem with blk_queue_invalidate_tags() which
will invalidate tags across all shared queues. This is a bit confusing,
the low level driver should call it for each queue seperately since
otherwise you cannot kill tags on just a single queue for eg a hard
drive that stops responding. Since the function has no callers
currently, it's not an issue.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-29 11:33:06 +01:00
Jens Axboe
fd5d806266 block: convert blkdev_issue_flush() to use empty barriers
Then we can get rid of ->issue_flush_fn() and all the driver private
implementations of that.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 11:05:02 +02:00
Jens Axboe
bf2de6f5a4 block: Initial support for data-less (or empty) barrier support
This implements functionality to pass down or insert a barrier
in a queue, without having data attached to it. The ->prepare_flush_fn()
infrastructure from data barriers are reused to provide this
functionality.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 11:03:56 +02:00
Jens Axboe
a0cd128542 block: add end_queued_request() and end_dequeued_request() helpers
We can use this helper in the elevator core for BLKPREP_KILL, and it'll
also be useful for the empty barrier patch.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 11:03:53 +02:00
Jens Axboe
2da96acde0 [BLOCK] Move sector_div() from blkdev.h to kernel.h
We need it even if CONFIG_BLOCK is disabled, so move it outside of
the block layer include system.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-12 12:40:38 +02:00
NeilBrown
d24517d793 Remove flush_dry_bio_endio
The entire function of flush_dry_bio_endio is to undo the effects
of bio_endio (when called on a barrier request).  So remove the
function and the call to bio_endio.

This allows us to remove "bi_size" from "struct request_queue".

Signed-off-by: Neil Brown <neilb@suse.de>

### Diffstat output
 ./block/ll_rw_blk.c      |   39 ++-------------------------------------
 ./include/linux/blkdev.h |    1 -
 2 files changed, 2 insertions(+), 38 deletions(-)

diff .prev/block/ll_rw_blk.c ./block/ll_rw_blk.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:57 +02:00
Jens Axboe
f5ff8422bb Fix warnings with !CONFIG_BLOCK
Hide everything in blkdev.h with CONFIG_BLOCK isn't set, and fixup
the (few) files that fail to build because they were relying on blkdev.h
pulling in extra includes for them.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:57 +02:00
NeilBrown
66846572bf Stop exporting blk_rq_bio_prep
blk_rq_bio_prep is exported for use in exactly
one place.  That place can benefit from using
the new blk_rq_append_bio instead.
So
  - change dm-emc to call blk_rq_append_bio
  - stop exporting blk_rq_bio_prep, and
  - initialise rq_disk in blk_rq_bio_prep,
       as dm-emc needs it.

Signed-off-by: Neil Brown <neilb@suse.de>

diff .prev/block/ll_rw_blk.c ./block/ll_rw_blk.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:56 +02:00
NeilBrown
3001ca7712 New function blk_req_append_bio
ll_back_merge_fn is currently exported to SCSI where is it used,
together with blk_rq_bio_prep, in exactly the same way these
functions are used in __blk_rq_map_user.

So move the common code into a new function (blk_rq_append_bio), and
don't export ll_back_merge_fn any longer.

Signed-off-by: Neil Brown <neilb@suse.de>

diff .prev/block/ll_rw_blk.c ./block/ll_rw_blk.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:56 +02:00
NeilBrown
5705f70217 Introduce rq_for_each_segment replacing rq_for_each_bio
Every usage of rq_for_each_bio wraps a usage of
bio_for_each_segment, so these can be combined into
rq_for_each_segment.

We define "struct req_iterator" to hold the 'bio' and 'index' that
are needed for the double iteration.

Signed-off-by: Neil Brown <neilb@suse.de>

Various compile fixes by me...

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:56 +02:00
Qi Yong
4e97182a22 [patch] QUEUE_FLAG_READFULL QUEUE_FLAG_WRITEFULL comment fix
The two comments were transposed.

Signed-off-by: Qi Yong <qiyong@mail.fc-cn.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-27 08:08:24 +02:00
Jens Axboe
71f65e6bd7 [BLOCK] Add request_queue_t and mark it deprecated
Andrew thinks I should be nice and allow outside code to at least just
compile, so add the request_queue_t typedef back and mark it deprecated.
It'll warn people that this type is going away soonish.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-24 10:29:42 +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
FUJITA Tomonori
41e1703b9b [SCSI] bsg: unexport sg v3 helper functions
blk_fill_sghdr_rq, blk_unmap_sghdr_rq, and blk_complete_sghdr_rq were
exported for bsg, however bsg was changed to support only sg v4.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-07-22 08:48:41 -05:00
Christoph Lameter
2a7326b5bb CONFIG_BOUNCE to avoid useless inclusion of bounce buffer logic
The bounce buffer logic is included on systems that do not need it.  If a
system does not have zones like ZONE_DMA and ZONE_HIGHMEM that can lead to
the use of bounce buffers then there is no need to reserve memory pools etc
etc.  This is true f.e.  for SGI Altix.

Also nicifies the Makefile and gets rid of the tricky "and" there.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 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
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
FUJITA Tomonori
45e79a3acd bsg: add a request_queue argument to scsi_cmd_ioctl()
bsg uses scsi_cmd_ioctl() for some SCSI/sg ioctl
commands. scsi_cmd_ioctl() gets a request queue from a gendisk
arguement. This prevents bsg being bound to SCSI devices that don't
have a gendisk (like OSD). This adds a request_queue argument to
scsi_cmd_ioctl(). The SCSI/sg ioctl commands doesn't use a gendisk so
it's safe for any SCSI devices to use scsi_cmd_ioctl().

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-16 08:52:45 +02:00
FUJITA Tomonori
337ad41dea block: export blk_verify_command for SG v4
blk_fill_sghdr_rq doesn't work for SG v4 so verify_command needed to
be exported.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-16 08:52:44 +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
Benjamin Gilbert
7deeed1317 [TRIVIAL PATCH] Kill blk_congestion_wait() stub for !CONFIG_BLOCK
blk_congestion_wait() doesn't exist anymore, but there's still a stub
in blkdev.h for the !CONFIG_BLOCK case.  Kill it.

Signed-off-by: Benjamin Gilbert <bgilbert@cs.cmu.edu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-10 08:03:32 +02:00
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
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
Jens Axboe
aaf1228ddf cfq-iosched: remove cfq_io_context last_queue
It hasn't been used for a while, kill it off and remove the old
if 0 code chunk.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-02-11 23:14:44 +01:00
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
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
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
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
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
Jens Axboe
cea2885a2e [PATCH] ide-cd: fix breakage with internally queued commands
We still need to maintain a private PC style command, since it
isn't completely unified with REQ_TYPE_BLOCK_PC yet.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-10-12 15:08:51 +02:00
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
Andrew Morton
bcfd8d3615 [PATCH] CONFIG_BLOCK: blk_congestion_wait() fix
Don't just do nothing: it'll cause busywaits all over writeback and page
reclaim.

For now, take a fixed-length nap.  Will improve when NFS starts waking up
throttled processes.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:52:33 +02:00
David Howells
9361401eb7 [PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer.  Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.

This patch does the following:

 (*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
     support.

 (*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
     an item that uses the block layer.  This includes:

     (*) Block I/O tracing.

     (*) Disk partition code.

     (*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.

     (*) The SCSI layer.  As far as I can tell, even SCSI chardevs use the
     	 block layer to do scheduling.  Some drivers that use SCSI facilities -
     	 such as USB storage - end up disabled indirectly from this.

     (*) Various block-based device drivers, such as IDE and the old CDROM
     	 drivers.

     (*) MTD blockdev handling and FTL.

     (*) JFFS - which uses set_bdev_super(), something it could avoid doing by
     	 taking a leaf out of JFFS2's book.

 (*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
     linux/elevator.h contingent on CONFIG_BLOCK being set.  sector_div() is,
     however, still used in places, and so is still available.

 (*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
     parts of linux/fs.h.

 (*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.

 (*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.

 (*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
     is not enabled.

 (*) fs/no-block.c is created to hold out-of-line stubs and things that are
     required when CONFIG_BLOCK is not set:

     (*) Default blockdev file operations (to give error ENODEV on opening).

 (*) Makes some /proc changes:

     (*) /proc/devices does not list any blockdevs.

     (*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.

 (*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.

 (*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
     given command other than Q_SYNC or if a special device is specified.

 (*) In init/do_mounts.c, no reference is made to the blockdev routines if
     CONFIG_BLOCK is not defined.  This does not prohibit NFS roots or JFFS2.

 (*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
     error ENOSYS by way of cond_syscall if so).

 (*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
     CONFIG_BLOCK is not set, since they can't then happen.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:52:31 +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
dc72ef4ae3 [PATCH] Add blk_start_queueing() helper
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 <axboe@suse.de>
2006-09-30 20:29:40 +02:00
Jens Axboe
b5deef9012 [PATCH] Make sure all block/io scheduler setups are node aware
Some were kmalloc_node(), some were still kmalloc(). Change them all to
kmalloc_node().

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:29:39 +02:00
Jens Axboe
a3b05e8f58 [PATCH] Kill various deprecated/unused block layer defines/functions
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:29:38 +02:00
Jens Axboe
fc46379daf [PATCH] cfq-iosched: kill cfq_exit_lock
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 <axboe@suse.de>
2006-09-30 20:29:36 +02:00
Jens Axboe
e6a1c874a0 [PATCH] struct request: shrink and optimize some more
Move some members around and unionize completion_data and rb_node since
they cannot ever be used at the same time.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:29:35 +02:00
Jens Axboe
cdd6026217 [PATCH] Remove ->rq_status from struct request
After Christophs SCSI change, the only usage left is RQ_ACTIVE
and RQ_INACTIVE. The block layer sets RQ_INACTIVE right before freeing
the request, so any check for RQ_INACTIVE in a driver is a bug and
indicates use-after-free.

So kill/clean the remaining users, straight forward.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:29:23 +02:00
Jens Axboe
49171e5c6f [PATCH] Remove struct request_list from struct request
It is always identical to &q->rq, and we only use it for detecting
whether this request came out of our mempool or not. So replace it
with an additional ->flags bit flag.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:29:22 +02:00
Jens Axboe
c00895ab2f [PATCH] Remove ->waiting member from struct request
As the comments indicates in blkdev.h, we can fold it into ->end_io_data
usage as that is really what ->waiting is. Fixup the users of
blk_end_sync_rq().

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:29:12 +02:00
Jens Axboe
ff7d145fd9 [PATCH] Add one more pointer to struct request for IO scheduler usage
Then we have enough room in the request to get rid of the dynamic
allocations in CFQ/AS.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:27:01 +02:00
Jens Axboe
9e2585a8a2 [PATCH] as-iosched: remove arq->is_sync member
We can track this in struct request.

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
2006-09-30 20:27:00 +02:00
Jens Axboe
2e662b65f0 [PATCH] elevator: abstract out the rbtree sort handling
The rbtree sort/lookup/reposition logic is mostly duplicated in
cfq/deadline/as, so move it to the elevator core. The io schedulers
still provide the actual rb root, as we don't want to impose any sort
of specific handling on the schedulers.

Introduce the helpers and rb_node in struct request to help migrate the
IO schedulers.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:26:57 +02:00
Jens Axboe
9817064b68 [PATCH] elevator: move the backmerging logic into the elevator core
Right now, every IO scheduler implements its own backmerging (except for
noop, which does no merging). That results in duplicated code for
essentially the same operation, which is never a good thing. This patch
moves the backmerging out of the io schedulers and into the elevator
core. We save 1.6kb of text and as a bonus get backmerging for noop as
well. Win-win!

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:26:56 +02:00
Jens Axboe
4aff5e2333 [PATCH] Split struct request ->flags into two parts
Right now ->flags is a bit of a mess: some are request types, and
others are just modifiers. Clean this up by splitting it into
->cmd_type and ->cmd_flags. This allows introduction of generic
Linux block message types, useful for sending generic Linux commands
to block devices.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:23:37 +02:00
Alexey Dobriyan
6c5c934153 [PATCH] ifdef blktrace debugging fields
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:09 -07:00
James Bottomley
1aedf2ccc6 Merge mulgrave-w:git/linux-2.6
Conflicts:

	include/linux/blkdev.h

Trivial merge to incorporate tag prototypes.
2006-09-23 21:03:52 -05:00
Trond Myklebust
275a082fe9 Add a real API for dealing with blk_congestion_wait()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:54 -04:00
James Bottomley
492dfb4896 [SCSI] block: add support for shared tag maps
The current block queue implementation already contains most of the
machinery for shared tag maps.  The only remaining pieces are a way to
allocate and destroy a tag map independently of the queues (so that
the maps can be managed on the life cycle of the overseeing entity)

Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-08-31 11:17:18 -04:00
Jens Axboe
8f34ee75de [PATCH] Rearrange a few struct request members
This saves 8 bytes of data in 64-bit archs.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-06-23 17:10:39 +02:00
Jens Axboe
ad3caddaa1 [PATCH] Get rid of struct request request_pm_state member
The IDE power management can just use the ->end_io_data member to store
it's data.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-06-23 17:10:39 +02:00
Jens Axboe
b31dc66a54 [PATCH] Kill PF_SYNCWRITE flag
A process flag to indicate whether we are doing sync io is incredibly
ugly. It also causes performance problems when one does a lot of async
io and then proceeds to sync it. Part of the io will go out as async,
and the other part as sync. This causes a disconnect between the
previously submitted io and the synced io. For io schedulers such as CFQ,
this will cause us lost merges and suboptimal behaviour in scheduling.

Remove PF_SYNCWRITE completely from the fsync/msync paths, and let
the O_DIRECT path just directly indicate that the writes are sync
by using WRITE_SYNC instead.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-06-23 17:10:39 +02:00
Linus Torvalds
28e4b22495 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: (85 commits)
  [SCSI] 53c700: remove reliance on deprecated cmnd fields
  [SCSI] hptiop: don't use cmnd->bufflen
  [SCSI] hptiop: HighPoint RocketRAID 3xxx controller driver
  [SCSI] aacraid: small misc. cleanups
  [SCSI] aacraid: Update supported product information
  [SCSI] aacraid: Fix return code interpretation
  [SCSI] scsi_transport_sas: fix panic in sas_free_rphy
  [SCSI] remove RQ_SCSI_* flags
  [SCSI] remove scsi_request infrastructure
  [SCSI] mptfusion: change driver revision to 3.03.10
  [SCSI] mptfc: abort of board reset leaves port dead requiring reboot
  [SCSI] mptfc: fix fibre channel infinite request/response loop
  [SCSI] mptfc: set fibre channel fw target missing timers to one second
  [SCSI] mptfusion: move fc event/reset handling to mptfc
  [SCSI] spi transport: don't allow dt to be set on SE or HVD buses
  [SCSI] aic7xxx: expose the bus setting to sysfs
  [SCSI] scsi: remove Documentation/scsi/cpqfc.txt
  [SCSI] drivers/scsi: Use ARRAY_SIZE macro
  [SCSI] Remove last page_address from dc395x.c
  [SCSI] hptiop: HighPoint RocketRAID 3xxx controller driver
  ...

Fixed up conflicts in drivers/message/fusion/mptbase.c manually (due to
the sparc interrupt cleanups)
2006-06-21 11:18:25 -07:00
Christoph Hellwig
8d7feac3c7 [SCSI] remove RQ_SCSI_* flags
The RQ_SCSI_* flags are a vestiage of a long past history.  The EH code
still sets them but we never make use of that information.  The other
users is pluto.c which never had a chance to work but needs to be kept
compiling to keep Davem happy, so copy over the definition there.

We could probably get rid of RQ_ACTIVE/RQ_INACTIVE aswell with some
work, there's only two more or less bogus looking uses in ubd and scsi.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-06-10 16:25:21 -05:00
David Woodhouse
62c4f0a2d5 Don't include linux/config.h from anywhere else in include/
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-04-26 12:56:16 +01:00
Christoph Hellwig
21b2f0c803 [SCSI] unify SCSI_IOCTL_SEND_COMMAND implementations
We currently have two implementations of this obsolete ioctl, one in
the block layer and one in the scsi code.  Both of them have drawbacks.

This patch kills the scsi layer version after updating the block version
with the missing bits:

 - argument checking
 - use scatterlist I/O
 - set number of retries based on the submitted command

This is the last user of non-S/G I/O except for the gdth driver, so
getting this in ASAP and through the scsi tree would be nie to kill
the non-S/G I/O path.  Jens, what do you think about adding a check
for non-S/G I/O in the midlayer?

Thanks to  Or Gerlitz for testing this patch.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-04-13 10:13:15 -05:00
Jens Axboe
206dc69b31 [BLOCK] cfq-iosched: seek and async performance fixes
Detect whether a given process is seeky and if so disable (mostly) the
idle window if it is. We still allow just a little idle time, just enough
to allow that process to submit a new request. That is needed to maintain
fairness across priority groups.

In some cases, we could setup several async queues. This is not optimal
from a performance POV, since we want all async io in one queue to perform
good sorting on it. It also impacted sync queues, as async io got too much
slice time.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-28 13:03:44 +02:00
Jens Axboe
e2d74ac066 [PATCH] [BLOCK] cfq-iosched: change cfq io context linking from list to tree
On setups with many disks, we spend a considerable amount of time
looking up the process-disk mapping on each queue of io. Testing with
a NULL based block driver, this costs 40-50% reduction in throughput
for 1000 disks.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-28 08:59:01 +02:00
Jens Axboe
2056a782f8 [PATCH] Block queue IO tracing support (blktrace) as of 2006-03-23
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-23 20:00:26 +01:00
Al Viro
483f4afc42 [PATCH] fix sysfs interaction and lifetime rules handling for queues 2006-03-18 18:34:37 -05:00
Al Viro
d9ff418793 [PATCH] make cfq_exit_queue() prune the cfq_io_context for that queue
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-03-18 18:34:07 -05:00
Al Viro
12a0573215 [PATCH] keep sync and async cfq_queue separate
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-03-18 18:34:02 -05:00
Jens Axboe
2cb2e147a6 [BLOCK] ll_rw_blk: make max_sectors and max_hw_sectors unsigned ints
IDE lba48 can support full 64k request size, which overflows the
max_hw_sectors variable.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-01-24 10:06:19 +01:00
Linus Torvalds
e2688f00dc Merge branch 'blk-softirq' of git://brick.kernel.dk/data/git/linux-2.6-block
Manual merge for trivial #include changes
2006-01-09 09:26:40 -08:00
Jens Axboe
ff856bad67 [BLOCK] ll_rw_blk: Enable out-of-order request completions through softirq
Request completion can be a quite heavy process, since it needs to
iterate through the entire request and complete the bio's it holds.
This patch adds blk_complete_request() which moves this processing
into a dedicated block softirq.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-01-09 16:02:34 +01:00
Jens Axboe
356cebea11 [BLOCK] Kill blk_attempt_remerge()
It's a broken interface, it's done way too late. And apparently it triggers
slab problems in recent kernels as well (most likely after the generic dispatch
code was merged). So kill it, ide-cd is the only user of it.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-01-09 15:30:20 +01:00
Jens Axboe
15fc858a00 [BLOCK] Correct blk_execute_rq_nowait() prototype 2006-01-06 10:00:50 +01:00
Tejun Heo
797e7dbbee [BLOCK] reimplement handling of barrier request
Reimplement handling of barrier requests.

* Flexible handling to deal with various capabilities of
  target devices.
* Retry support for falling back.
* Tagged queues which don't support ordered tag can do ordered.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-01-06 09:51:03 +01:00
Tejun Heo
8ffdc6550c [BLOCK] add @uptodate to end_that_request_last() and @error to rq_end_io_fn()
add @uptodate argument to end_that_request_last() and @error
to rq_end_io_fn().  there's no generic way to pass error code
to request completion function, making generic error handling
of non-fs request difficult (rq->errors is driver-specific and
each driver uses it differently).  this patch adds @uptodate
to end_that_request_last() and @error to rq_end_io_fn().

for fs requests, this doesn't really matter, so just using the
same uptodate argument used in the last call to
end_that_request_first() should suffice.  imho, this can also
help the generic command-carrying request jens is working on.

Signed-off-by: tejun heo <htejun@gmail.com>
Signed-Off-By: Jens Axboe <axboe@suse.de>
2006-01-06 09:49:03 +01:00
Mike Christie
defd94b754 [SCSI] seperate max_sectors from max_hw_sectors
- export __blk_put_request and blk_execute_rq_nowait
needed for async REQ_BLOCK_PC requests
- seperate max_hw_sectors and max_sectors for block/scsi_ioctl.c and
SG_IO bio.c helpers per Jens's last comments. Since block/scsi_ioctl.c SG_IO was
already testing against max_sectors and SCSI-ml was setting max_sectors and
max_hw_sectors to the same value this does not change any scsi SG_IO behavior. It only
prepares ll_rw_blk.c, scsi_ioctl.c and bio.c for when SCSI-ml begins to set
a valid max_hw_sectors for all LLDs. Today if a LLD does not set it
SCSI-ml sets it to a safe default and some LLDs set it to a artificial low
value to overcome memory and feedback issues.

Note: Since we now cap max_sectors to BLK_DEF_MAX_SECTORS, which is 1024,
drivers that used to call blk_queue_max_sectors with a large value of
max_sectors will now see the fs requests capped to BLK_DEF_MAX_SECTORS.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-15 15:11:40 -08:00
Mike Christie
17e01f216b [SCSI] add retries field to request for REQ_BLOCK_PC use
For tape we need to control the retries. This patch adds a retries
counter on the request for REQ_BLOCK_PC commands originating from
scsi_execute* to use. REQ_BLOCK_PC commands comming from the block
layer SG_IO path continue to use the retires set in the ULD init_command.
(scsi_execute* does not set the gendisk so we do not execute
the init_command in that path).

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-14 19:04:11 -08:00
Mike Christie
6e39b69e7e [SCSI] export blk layer functions needed for blk_execute_rq_nowait
To send async requests we need these two functions exported.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-14 19:00:50 -08:00
Tejun Heo
15853af9f0 [BLOCK] Implement elv_drain_elevator for improved switch error detection
This patch adds request_queue->nr_sorted which keeps the number of
requests in the iosched and implement elv_drain_elevator which
performs forced dispatching.  elv_drain_elevator checks whether
iosched actually dispatches all requests it has and prints error
message if it doesn't.  As buggy forced dispatching can result in
wrong barrier operations, I think this extra check is worthwhile.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2005-11-12 10:56:06 +01:00
Linus Torvalds
5dd962494f Merge branch 'elevator-switch' of git://brick.kernel.dk/data/git/linux-2.6-block
Manual fixup for trivial "gfp_t" changes.
2005-10-28 08:56:34 -07:00
Linus Torvalds
28d721e24c Merge branch 'generic-dispatch' of git://brick.kernel.dk/data/git/linux-2.6-block 2005-10-28 08:53:49 -07:00
Al Viro
8267e268e0 [PATCH] gfp_t: block layer core
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28 08:16:47 -07:00
Jens Axboe
64521d1a3b [BLOCK] elevator switch fixes/cleanup
- 100msec sleep is a little excessive, lots of requests can complete
  in that timeframe. Use 10msec instead.
- Rename QUEUE_FLAG_BYPASS to QUEUE_FLAG_ELVSWITCH to indicate what
  is going on.

Signed-off-by: Jens Axboe <axboe@suse.de>
2005-10-28 08:48:23 +02:00
Tejun Heo
cb98fc8bb9 [BLOCK] Reimplement elevator switch
This patch reimplements elevator switch.  This patch assumes generic
dispatch queue patchset is applied.

 * Each request is tagged with REQ_ELVPRIV flag if it has its elevator
   private data set.
 * Requests which doesn't have REQ_ELVPRIV flag set never enter
   iosched.  They are always directly back inserted to dispatch queue.
   Of course, elevator_put_req_fn is called only for requests which
   have its REQ_ELVPRIV set.
 * Request queue maintains the current number of requests which have
   its elevator data set (elevator_set_req_fn called) in
   q->rq->elvpriv.
 * If a request queue has QUEUE_FLAG_BYPASS set, elevator private data
   is not allocated for new requests.

 To switch to another iosched, we set QUEUE_FLAG_BYPASS and wait until
elvpriv goes to zero; then, we attach the new iosched and clears
QUEUE_FLAG_BYPASS.  New implementation is much simpler and main code
paths are less cluttered, IMHO.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2005-10-28 08:48:12 +02:00
Tejun Heo
cb19833dcc [BLOCK] kill generic max_back_kb handling
This patch kills max_back_kb handling from elv_dispatch_sort() and
kills max_back_kb field from struct request_queue.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2005-10-28 08:46:01 +02:00
Tejun Heo
06b86245c0 [PATCH] 03/05 move last_merge handlin into generic elevator code
Currently, both generic elevator code and specific ioscheds
participate in the management and usage of last_merge.  This
and the following patches move last_merge handling into
generic elevator code.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2005-10-28 08:45:20 +02:00
Jens Axboe
1b47f531e2 [PATCH] generic dispatch fixes
- Split elv_dispatch_insert() into two functions
- Rename rq_last_sector() to rq_end_sector()

Signed-off-by: Jens Axboe <axboe@suse.de>
2005-10-28 08:44:37 +02:00