Commit Graph

110833 Commits

Author SHA1 Message Date
Martin K. Petersen
0c032ab889 block: Fix double put in blk_integrity_unregister
- kobject_del already puts the parent.

 - Set integrity profile to NULL to prevent stale data.

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
Martin K. Petersen
74aa8c2cc0 block: Introduce integrity data ownership flag
A filesystem might supply its own integrity metadata.  Introduce a
flag that indicates whether the filesystem or the block layer owns the
integrity buffer.

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
Alberto Bertogli
8deaf72107 bio.h: Remove unused conditional code
The whole bio_integrity() definition is inside an #ifdef
CONFIG_BLK_DEV_INTEGRITY, there's no need for the conditional code.

Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar>
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
99cd3386f2 block: change elevator to use __blk_end_request()
This patch converts elevator to use __blk_end_request() directly
so that end_{queued|dequeued}_request() can be removed.
Related 'uptodate' arguments is converted to 'error'.

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
7afb3a6e75 gdrom: change to use __blk_end_request()
This patch converts gdrom to use __blk_end_request() directly
so that end_{queued|dequeued}_request() can be removed.

gd.transfer is '1' in error cases and '0' in non-error cases,
so gdrom hasn't been propagating any error code to the block layer.
We can just convert error cases to '-EIO'.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:21 +02:00
Kiyoshi Ueda
2a9df5055a memstick: change to use __blk_end_request()
This patch converts memstick to use __blk_end_request() directly
so that end_{queued|dequeued}_request() can be removed.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:20 +02:00
Kiyoshi Ueda
8316982ac0 virtio_blk: change to use __blk_end_request()
This patch converts virtio_blk to use __blk_end_request() directly
so that end_{queued|dequeued}_request() can be removed.
Related 'uptodate' argument is converted to 'error'.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:20 +02:00
Jens Axboe
0497b345e7 blktrace: use BLKTRACE_BDEV_SIZE as the name size for setup structure
Define as 32, which is is what BDEVNAME_SIZE is/was as well. This keeps
the user interface the same and gets rid of the difference between
kernel and user api here.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:20 +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
Elias Oltmanns
336c3d8ce7 block: Fix blk_start_queueing() to not kick a stopped queue
blk_start_queueing() should act like the generic queue unplugging
and kicking and ignore a stopped queue. Such a queue may not be
run until after a call to blk_start_queue().

Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:20 +02:00
Sven Schuetz
c0ddffa84a include blktrace_api.h in headers_install
This header file is of interest for user space programming, i.e.
for tools that process blktrace data.

We would like to use it for a tool on-top of blktrace which processes
data provided by blktrace. For this purpose, it would be helpful
if the blktrace API would make it to /usr/include/linux.

The git tree for the blktrace tools comes with its own copy of this header
file. I didn't manage to replace that copy with the file generated
by the patch below yet. A few more cleanups would be needed.
For example, the blktrace ioctl numbers, which are currently defined in
usr/include/fs.h, might need to be moved. Should be feasible, though.

Signed-off-by: Sven Schuetz <sven@linux.vnet.ibm.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:19 +02:00
Jens Axboe
e3ba9ae58a block: reserve some tags just for sync IO
By only allowing async IO to consume 3/4 ths of the tag depth, we
always have slots free to serve sync IO. This is important to avoid
having writes fill the entire tag queue, thus starving reads.

Original patch and idea from Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:19 +02:00
Jens Axboe
f7d7b7a7a3 block: as/cfq ssd idle check update
We really need to know about the hardware tagging support as well,
since if the SSD does not do tagging then we still want to idle.
Otherwise have the same dependent sync IO vs flooding async IO
problem as on rotational media.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:19 +02:00
Jens Axboe
8bff7c6b0f libata: set queue SSD flag for SSD devices
SSD devices should give an RPM setting of 1 in word 217 of the ID
page. If we see such a device, tell the block layer about it.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:19 +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
Keith Wansbrough
9e49184c82 floppy: support arbitrary first-sector numbers
The current floppy_struct allows floppies to number sectors starting
from 0 or 1.  This patch allows arbitrary first-sector numbers - for
example, 0xC1 for Amstrad CPC disks.

This extends the existing 1-bit field (FD_ZEROBASED, bit 2 of stretch)
to 8 bits (FD_SECTMASK, bits 2 to 9).

Currently 0x00 denotes a first sector number of 1, and 0x01 denotes a
first sector number of 0.  We extend this by interpreting FD_SECTMASK
as the first sector number with the LSB flipped.

Signed-off-by: Keith Wansbrough <keith@lochan.org>
Cc: Alain Knaff <alain@linux.lu>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: Karel Zak <kzak@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:19 +02:00
Julia Lawall
061837bc86 drivers/block: Use DIV_ROUND_UP
The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.

An extract of the semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP((n),d)
+ DIV_ROUND_UP(n,d)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP(n,(d))
+ DIV_ROUND_UP(n,d)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: <mike.miller@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:19 +02:00
scameron@beardog.cca.cpqcorp.net
905bd78f21 cciss: Fix cciss SCSI rescan code to better notice device changes
Fix cciss SCSI rescan code to better notice device changes.
If you hot-unplug a tape drive, then hot-plug a different
tape drive into the same slot in a storage enclosure,
the cciss driver wouldn't notice anything had changed, as
it was only looking at the LUN address and device type.
Now it looks at the inquiry page 0x83 device identifier,
and vendor and model strings as well.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cca.cpqcorp.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:18 +02:00
FUJITA Tomonori
79eb014578 fix an example of scatterlists handling in DMA-API.txt
This example isn't the proper way to handle scatterlists (can't handle
sg chaining).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:18 +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
e3335de940 block: blk_cleanup_queue() should call blk_sync_queue()
When a driver calls blk_cleanup_queue(), the device should be fully idle.
However, the block layer may have pending plugging timers and the IO
schedulers may have pending work in the work queues. So quisce the device
by waiting for the timer and flushing the work queues.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:18 +02:00
Chris Lalancette
9246b5f06d block: Expand Xen blkfront for > 16 xvd
Until recently, the maximum number of xvd block devices you could attach
to a Xen domU was 16. This limitation turned out to be problematic for
some users, so it was expanded to handle a much larger number of disks.
However, this requires a couple of changes in the way that blkfront
scans for disks. This functionality is already present in the Xen
linux-2.6.18-xen.hg tree; the attached patch adds this functionality to
the mainline xen-blkfront implementation. I successfully tested it on a
2.6.25 tree, and build tested it on 2.6.27-rc3.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
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
7ba1fbaa4a block: use rq complete marking in blk_abort_request()
We cannot abort a request if we raced with the timeout handler already,
or with the IO completion. So make blk_abort_request() mark the request
as complete, and only continue if we succeeded.

Found and suggested by Mike Anderson <andmike@linux.vnet.ibm.com>

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
Jens Axboe
0a0d96b03a block: add bio_kmalloc()
Not all callers need (or want!) the mempool backing guarentee, it
essentially means that you can only use bio_alloc() for short allocations
and not for preallocating some bio's at setup or init time.

So add bio_kmalloc() which does the same thing as bio_alloc(), except
it just uses kmalloc() as the backing instead of the bio mempools.

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
FUJITA Tomonori
4677735f03 sg: remove unnecessary blk_rq_unmap_user
blk_rq_unmap_user in sg_finish_rem_req can take care of all the cases.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:16 +02:00
FUJITA Tomonori
0b6cb26c66 sg: remove sg_read_xfer
sg_read_xfer was used to copy data to user space for READ
commands. blk_rq_unmap_user does the job so sg_read_xfer does nothing
useful.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:15 +02:00
FUJITA Tomonori
c3919af235 sg: remove sg_write_xfer
sg_write_xfer was used to copy data from user space for WRITE
commands. blk_rq_map_user_iov and blk_rq_map_user do the job so
sg_write_xfer does nothing useful.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:14 +02:00
FUJITA Tomonori
626710c9d6 sg: incorporate sg_build_direct into sg_start_req
Calling blk_rq_map_user() at a single place is better than at
different two places. It makes the code more understandable.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:14 +02:00
FUJITA Tomonori
44c7b0eaa0 sg: remove __sg_start_req
__sg_start_req() was used temporarily to call blk_get_request() during
converting sg to use the block layer.

Now sg always calls blk_get_request() so we can move blk_get_request()
to sg_start_req(). We don't need __sg_start_req anymore.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:14 +02:00
FUJITA Tomonori
fd1c1de076 sg: remove b_malloc_len in sg_scatter_hold struct
It's not used for anything useful after the block layer conversion.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:14 +02:00
FUJITA Tomonori
7e56cb0f7e sg: remove SG_ALLOW_DIO_CODE define
sg had lots of the own functions for the direct IO but now sg uses the
block layer functions for it. There are only five lines for the direct
IO. SG_ALLOW_DIO_CODE define was used to compile out the direct IO
code but we don't need the define. If someone wants to remove the
direct IO code, he can do easily without the define.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:14 +02:00
FUJITA Tomonori
a91a3a20e0 sg: rename sg_cmd_done sg_rq_end_io
old sg_rq_end_io() was used to wrap sg_cmd_done during converting sg
to use the block layer (in order to cover the difference
scsi_execute_async and blk_execute_rq_nowait). Now we don't need it so
let's remove it.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:14 +02:00
Mike Anderson
224cb3e981 dm: Call blk_abort_queue on failed paths
Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:14 +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
Andrew Patterson
608aeef17a Call flush_disk() after detecting an online resize.
We call flush_disk() to make sure the buffer cache for the disk is
flushed after a disk resize. There are two resize cases, growing and
shrinking. Given that users can shrink/then grow a disk before
revalidate_disk() is called, we treat the grow case identically to
shrinking. We need to flush the buffer cache after an online shrink
because, as James Bottomley puts it,

     The two use cases for shrinking I can see are

     1. planned: the fs is already shrunk to within the new boundaries
        and all data is relocated, so invalidate is fine (any dirty
        buffers that might exist in the shrunk region are there only
        because they were relocated but not yet written to their
        original location).
     2. unplanned:  In this case, the fs is probably toast, so whether
        we invalidate or not isn't going to make a whole lot of
        difference; it's still going to try to read or write from
        sectors beyond the new size and get I/O errors.

Immediately invalidating shrunk disks will cause errors for outstanding
I/Os for reads/write beyond the new end of the disk to be generated
earlier then if we waited for the normal buffer cache operation. It also
removes a potential security hole where we might keep old data around
from beyond the end of the shrunk disk if the disk was not invalidated.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:13 +02:00
Andrew Patterson
56ade44b46 Added flush_disk to factor out common buffer cache flushing code.
We need to be able to flush the buffer cache for for more than
just when a disk is changed, so we factor out common cache flush code
in check_disk_change() to an internal flush_disk() routine.  This
routine will then be used for both disk changes and disk resizes (in a
later patch).

Include the disk name in the text indicating that there are busy
inodes on the device and increase the KERN severity of the message.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:13 +02:00
Andrew Patterson
f98a8cae12 SCSI sd driver calls revalidate_disk wrapper.
Modify the SCSI disk driver to call the revalidate_disk()
wrapper. This allows us to do some housekeeping such as accounting for
a disk being resized online. The wrapper will call
sd_revalidate_disk() at the appropriate time.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:13 +02:00
Andrew Patterson
9bc3ffbfbd Check for device resize when rescanning partitions
Check for device resize in the rescan_partitions() routine. If the device
has been resized, the bdev size is set to match. The rescan_partitions()
routine is called when opening the device and when calling the
BLKRRPART ioctl.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:12 +02:00
Andrew Patterson
c3279d1454 Adjust block device size after an online resize of a disk.
The revalidate_disk routine now checks if a disk has been resized by
comparing the gendisk capacity to the bdev inode size.  If they are
different (usually because the disk has been resized underneath the kernel)
the bdev inode size is adjusted to match the capacity.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:12 +02:00
Andrew Patterson
0c002c2f74 Wrapper for lower-level revalidate_disk routines.
This is a wrapper for the lower-level revalidate_disk call-backs such
as sd_revalidate_disk(). It allows us to perform pre and post
operations when calling them.

We will use this wrapper in a later patch to adjust block device sizes
after an online resize (a _post_ operation).

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:12 +02:00
Tejun Heo
243294dae0 block: fix duplicate headers for /proc/partitions
seqf can be started multiple times for a read and the header should be
printed only for the initial one.  Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:12 +02:00
FUJITA Tomonori
fad7f01e61 sg: set dxferp to NULL for READ with the older SG interface
With the older SG interface, we don't know a user-space address to
trasfer data when executing a SCSI command. So we can't pass a
user-space address to blk_rq_map_user.

This patch fixes sg to pass a NULL user-space address to
blk_rq_map_user so that it just sets up a request and bios with page
frames propely without data transfer.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:12 +02:00