As bi_end_io is only called once when the reqeust is complete,
the 'size' argument is now redundant. Remove it.
Now there is no need for bio_endio to subtract the size completed
from bi_size. So don't do that either.
While we are at it, change bi_end_io to return void.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
The only caller of bio_endio that does not pass the full bi_size
is end_that_request_first. Also, no ->bi_end_io method is really
interested in bi_size being decremented.
So move the decrement and related code into ll_rw_blk and merge it
with order_bio_endio to form req_bio_endio which does endio functionality
specific to request completion.
As some ->bi_end_io methods do check bi_size of 0, we set it thus for
now, but that will go in the next patch.
Signed-off-by: Neil Brown <neilb@suse.de>
### Diffstat output
./block/ll_rw_blk.c | 42 +++++++++++++++++++++++++++---------------
./fs/bio.c | 23 +++++++++++------------
2 files changed, 38 insertions(+), 27 deletions(-)
diff .prev/block/ll_rw_blk.c ./block/ll_rw_blk.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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>
blk_cpu_notifier is marked as __devinitdata, but __devinitdata need not
be __init even if HOTPLUG_CPU=n, which wastes space. It should be marked
__cpuinitdata, and the callback itself as __cpuinit.
Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
These have very similar functions and should share code where
possible.
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>
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>
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>
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>
blk_recalc_rq_segments calls blk_recount_segments on each bio,
then does some extra calculations to handle segments that overlap
two bios.
If we merge the code from blk_recount_segments into
blk_recalc_rq_segments, we can process the whole request one bio_vec
at a time, and not need the messy cross-bio calculations.
Then blk_recount_segments can be implemented by calling
blk_recalc_rq_segments, passing it a simple on-stack request which
stores just the bio.
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>
Should add some comments for the tag barriers (they won't be so important
if we can switch over to the explicit _lock bitops, but for now we should
make it clear).
Jens' original patch said a barrier after the test_and_clear_bit was also
required. I can't see why (and it would prevent the use of the _lock bitop).
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
--
There's a race condition in blk_queue_end_tag() for shared tag maps,
users include stex (promise supertrak thingy) and qla2xxx. The former
at least has reported bugs in this area, not sure why we haven't seen
any for the latter. It could be because the window is narrow and that
other conditions in the qla2xxx code hide this. It's a real bug,
though, as the stex smp users can attest.
We need to ensure two things - the tag bit clearing needs to happen
AFTER we cleared the tag pointer, as the tag bit clearing/setting is
what protects this map. Secondly, we need to ensure that the visibility
of the tag pointer and tag bit clear are ordered properly.
[ I removed the SMP barriers - "test_and_clear_bit()" already implies
all the required barriers. -- Linus ]
Also see http://bugzilla.kernel.org/show_bug.cgi?id=7842
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch provides more information concerning REMAP operations on block
IOs. The additional information provides clearer details at the user level,
and supports post-processing analysis in btt.
o Adds in partition remaps on the same device.
o Fixed up the remap information in DM to be in the right order
o Sent up mapped-from and mapped-to device information
Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This updates sg_io_v4 structure (based on Doug's RFC, release 1.3).
The major changes are:
- add dout_resid field
- increase tag size to 64 bits to comply with SAM-4 and SRP
- add dout_iovec_count and din_iovec_count
dout_iovec_count and din_iovec_count aren't supported now. I'm not
sure whether they will be supported or not but they were added for the
possible future changes.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
* master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6: (28 commits)
[SCSI] mpt fusion: Changes in mptctl.c for logging support
[SCSI] mpt fusion: Changes in mptfc.c mptlan.c mptsas.c and mptspi.c for logging support
[SCSI] mpt fusion: Changes in mptscsih.c for logging support
[SCSI] mpt fusion: Changes in mptbase.c for logging support
[SCSI] mpt fusion: logging support in Kconfig, Makefile, mptbase.h and addition of mptdebug.h
[SCSI] libsas: Fix potential NULL dereference in sas_smp_get_phy_events()
[SCSI] bsg: Fix build for CONFIG_BLOCK=n
[SCSI] aacraid: fix Sunrise Lake reset handling
[SCSI] aacraid: add SCSI SYNCHONIZE_CACHE range checking
[SCSI] add easyRAID to the no report luns blacklist
[SCSI] advansys: lindent and other large, uninteresting changes
[SCSI] aic79xx, aic7xxx: Fix incorrect width setting
[SCSI] qla2xxx: fix to honor ignored parameters in sysfs attributes
[SCSI] aacraid: draw line in sand, sundry cleanup and version update
[SCSI] iscsi_tcp: Turn off bounce buffers
[SCSI] libiscsi: fix cmd seqeunce number checking
[SCSI] iscsi_tcp, ib_iser Enable module refcounting for iscsi host template
[SCSI] libiscsi: make sure session is not blocked when removing host
[SCSI] libsas: Remove PCI dependencies
[SCSI] simscsi: convert to use the data buffer accessors
...
BLK_DEV_BSG was added outside of the if BLOCK check, which allows it to
be enabled when CONFIG_BLOCK=n. This leads to many screenlengths of
errors, starting with a parse error on the request_queue_t definition.
Obviously this wasn't intended for CONFIG_BLOCK=n usage, so just move the
option back in to the block.
Caught with a randconfig on sh.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
use cpu_clock() instead of sched_clock(). (the latter is not a proper
clock-source)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
BLK_DEV_BSG was added outside of the if BLOCK check, which allows it to
be enabled when CONFIG_BLOCK=n. This leads to many screenlengths of
errors, starting with a parse error on the request_queue_t definition.
Obviously this wasn't intended for CONFIG_BLOCK=n usage, so just move the
option back in to the block.
Caught with a randconfig on sh.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
--
block/Kconfig | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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>
- kill uhdr in bsg_command structure
- it's not necessary to put SG v4 stuff to block/scsi_ioctl.c
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This replaces the current linear search for a unique minor number with
lib/idr.c.
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@SteelEye.com>
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>
scsi_sysfs_add_sdev ignores the bsg_register_queue failure, so
bsg_unregister_queue must check whether the queue has a bsg device.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Currently, bsg doesn't make class backlinks (a process whereby you'd get
a link to bsg in the device directory in the same way you get one for
sg). This is because the bsg device is uninitialised, so the class
device has nothing it can attach to. The fix is to make the bsg device
point to the cdevice of the entity creating the bsg, necessitating
changing the bsg_register_queue() prototype into a form that takes the
generic device.
Acked-by: FUJITA Tomonori <tomof@acm.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
unfortunately, if IS_ERR(class_dev) is true, that means class_dev isn't
null and the check in the error leg is pointless ... it's also asking
for trouble to request unregistration of a device we haven't actually
created (although it works currently). Fix by using explicit gotos and
unregisters.
Acked-by: FUJITA Tomonori <tomof@acm.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
There are some leftover bits from the task cooperator patch, that was
yanked out again. While it will get reintroduced, no point in having
this write-only stuff in the tree. So yank it.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
If we have two processes with different ioprio_class, but the same
ioprio_data, their async requests will fall into the same queue. I guess
such behavior is not expected, because it's not right to put real-time
requests and best-effort requests in the same queue.
The attached patch fixes the problem by introducing additional *cfqq
fields on cfqd, pointing to per-(class,priority) async queues.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.
This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch moves the bsg registration into SCSI so that bsg no longer
has a dependency on the scsi_interface_register API.
This can be viewed as a temporary expedient until we can get universal
bsg binding sorted out properly. Also use the sdev bus_id as the
generic bsg name (to avoid clashes with the queue name).
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc).
Here is a short excerpt of the semantic patch performing
this transformation:
@@
type T2;
expression x;
identifier f,fld;
expression E;
expression E1,E2;
expression e1,e2,e3,y;
statement S;
@@
x =
- kmalloc
+ kzalloc
(E1,E2)
... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\)
- memset((T2)x,0,E1);
@@
expression E1,E2,E3;
@@
- kzalloc(E1 * E2,E3)
+ kcalloc(E1,E2,E3)
[akpm@linux-foundation.org: get kcalloc args the right way around]
Signed-off-by: Yoann Padioleau <padator@wanadoo.fr>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg KH <greg@kroah.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'bsg' of git://git.kernel.dk/data/git/linux-2.6-block:
bsg: fix missing space in version print
Don't define empty struct bsg_class_device if !CONFIG_BLK_DEV_BSG
bsg: Kconfig updates
bsg: minor cleanup
bsg: device hash table cleanup
bsg: fix initialization error handling bugs
bsg: mark FUJITA Tomonori as bsg maintainer
bsg: convert to dynamic major
bsg: address various review comments
Put WARN_ON and fixed all callers of unregister_blkdev(). Now we can make
unregister_blkdev return void.
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When unregister_blkdev() has failed, something wrong happened. This patch
adds WARN_ON to notify of such badness.
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing
variant in the past. But with __GFP_ZERO it is possible now to do zeroing
while allocating.
Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever
we can.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tomo introduced a bug in his commit, removing the space between
"driver" and "version" in the init printk.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
- add the detailed explanation.
- remove 'default y'.
- make 'EXPERIMENTAL' keyword visible to the user in menu.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This fixes the following bugs and cleans up the initialization code:
- cdev_del is missing.
- unregister_chrdev_region should be used instead of unregister_chrdev.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
240 was hardcoded, that was clearly a dumb mistake. Convert bsg
to use alloc_chrdev_region() to retrieve a dynamic major.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This address most of the comments made by Andrew. The two remaining
are conversion to idr, and dynamic major.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
The SCSI code can be compiled modular, but BLK_DEV_BSG currently cannot,
and depends on the SCSI layer. So make sure that it depends on the SCSI
layer being compiled in, not just available as a module.
Noticed by Jeff Garzik and S.Çağlar Onur.
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: S.Çağlar Onur <caglar@pardus.org.tr>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We had a merge issue with the "dentry" field going away from the
kobject, and being replaced by a sysfs_dirent field (named "sd")
instead. That broke the BSG compile.
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This updates bsg entry in Kconfig:
- bsg supports sg v4
- bsg depends on SCSI
- it might be better to mark it experimental for a while
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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>
The previous commit introduced a deadlock in discarding commands,
because we forget to unlock the bd spinlock.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch fixes a bug that read() returns ENODATA even with a
blocking file descriptor when there are no commands pending.
This also includes some cleanups.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This fixes the following minor issues:
- add EXPORT_SYMBOL_GPL for bsg_register_queue and
bsg_unregister_queue.
- shut up gcc warnings
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <axboe@nelson.home.kernel.dk>
This patch addresses on two issues on bsg device allocation.
- the current maxium number of bsg devices is 256. It's too small if
we allocate bsg devices to all SCSI devices, transport entities, etc.
This increses the maxium number to 32768 (taken from the sg driver).
- SCSI devices are dynamically added and removed. Currently, bsg can't
handle it well since bsd_device->minor is simply increased.
This is dependent on the patchset that I posted yesterday:
http://marc.info/?l=linux-scsi&m=117440208726755&w=2
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch binds bsg to all SCSI devices (their request queues) like
the current sg driver does. We can send SCSI commands to non disk and
cdrom scsi devices like OSD via bsg.
This patch removes bsg_register_queue from blk_register_queue so bsg
devices aren't bound to non SCSI block devices. If they want bsg, I'll
send a patch to do that.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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>
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>
Just get rid of the preallocated command map, use the slab cache
to get/free commands instead.
Original patch from FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>,
changed by me to not use a mempool.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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>
This just kills linux/config.h and dprintk warnings.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This converts block/scsi_ioctl.c use blk_rq_unmap_user new
API. blk_unmap_sghdr_rq is too simple and it might be better to remove
it.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
instead of going through all options.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
With the cfq_queue hash removal, we inadvertently got rid of the
async queue sharing. This was not intentional, in fact CFQ purposely
shares the async queue per priority level to get good merging for
async writes.
So put some logic in cfq_get_queue() to track the shared queues.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Barrier bios are completed twice - once after the barrier write itself
is done and again after the whole sequence is complete.
flush_dry_bio_endio() is for the first completion. It doesn't really
complete the bio. It rewinds bvec and resets bio so that it can be
completed again when the whole barrier sequence is complete.
The bvec rewinding code has the following problems.
1. The rewinding code is wrong because filesystems may pass bvec with
non zero bv_offset.
2. The block layer doesn't guarantee anything about the state of
bvec array on request completion. bv_offset and len are updated
iff __end_that_request_first() completes the bvec partially.
Because of #2, #1 doesn't really matter (nobody cares whether bvec is
re-wound correctly or not) but then again by not doing unwinding at
all, we'll always give back the same bvec to the caller as full bvec
completion doesn't alter bvecs and the final completion is always full
completion.
Drop unnecessary rewinding code.
This is spotted by Neil Brown.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Two bugs in there:
- The virt oversize check should use the current bio hardware back
size and the next bio front size, not the same bio. Spotted by
Neil Brown.
- The segment size check should add hw front sizes, not total bio
sizes. Spotted by James Bottomley
Acked-by: James Bottomley <James.Bottomley@SteelEye.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
SCSI marks internal commands with REQ_PREEMPT and push it at the front
of the request queue using blk_execute_rq(). When entering suspended
or frozen state, SCSI devices are quiesced using
scsi_device_quiesce(). In quiesced state, only REQ_PREEMPT requests
are processed. This is how SCSI blocks other requests out while
suspending and resuming. As all internal commands are pushed at the
front of the queue, this usually works.
Unfortunately, this interacts badly with ordered requeueing. To
preserve request order on requeueing (due to busy device, active EH or
other failures), requests are sorted according to ordered sequence on
requeue if IO barrier is in progress.
The following sequence deadlocks.
1. IO barrier sequence issues.
2. Suspend requested. Queue is quiesced with part or all of IO
barrier sequence at the front.
3. During suspending or resuming, SCSI issues internal command which
gets deferred and requeued for some reason. As the command is
issued after the IO barrier in #1, ordered requeueing code puts the
request after IO barrier sequence.
4. The device is ready to process requests again but still is in
quiesced state and the first request of the queue isn't
REQ_PREEMPT, so command processing is deadlocked -
suspending/resuming waits for the issued request to complete while
the request can't be processed till device is put back into
running state by resuming.
This can be fixed by always putting !fs requests at the front when
requeueing.
The following thread reports this deadlock.
http://thread.gmane.org/gmane.linux.kernel/537473
Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: David Greaves <david@dgreaves.com>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Send an uevent to user space to indicate that a media change event has
occurred.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow user space to determine if a disk supports Asynchronous Notification of
media changes. This is done by adding a new sysfs file "capability_flags",
which is documented in (insert file name). This sysfs file will export all
disk capabilities flags to user space. We also define a new flag to define
the media change notification capability.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
current_io_context() is both static and exported with EXPORT_SYMBOL().
As there are no users outside of ll_rw_blk.c itself, just kill the
export.
Problem reported by Martin Michlmayr <tbm@cyrius.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
to generic_make_request can use up a lot of space, and we would rather they
didn't.
As generic_make_request is a void function, and as it is generally not
expected that it will have any effect immediately, it is safe to delay any
call to generic_make_request until there is sufficient stack space
available.
As ->bi_next is reserved for the driver to use, it can have no valid value
when generic_make_request is called, and as __make_request implicitly
assumes it will be NULL (ELEVATOR_BACK_MERGE fork of switch) we can be
certain that all callers set it to NULL. We can therefore safely use
bi_next to link pending requests together, providing we clear it before
making the real call.
So, we choose to allow each thread to only be active in one
generic_make_request at a time. If a subsequent (recursive) call is made,
the bio is linked into a per-thread list, and is handled when the active
call completes.
As the list of pending bios is per-thread, there are no locking issues to
worry about.
I say above that it is "safe to delay any call...". There are, however,
some behaviours of a make_request_fn which would make it unsafe. These
include any behaviour that assumes anything will have changed after a
recursive call to generic_make_request.
These could include:
- waiting for that call to finish and call it's bi_end_io function.
md use to sometimes do this (marking the superblock dirty before
completing a write) but doesn't any more
- inspecting the bio for fields that generic_make_request might
change, such as bi_sector or bi_bdev. It is hard to see a good
reason for this, and I don't think anyone actually does it.
- inspecing the queue to see if, e.g. it is 'full' yet. Again, I
think this is very unlikely to be useful, or to be done.
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <dm-devel@redhat.com>
Alasdair G Kergon <agk@redhat.com> said:
I can see nothing wrong with this in principle.
For device-mapper at the moment though it's essential that, while the bio
mappings may now get delayed, they still get processed in exactly
the same order as they were passed to generic_make_request().
My main concern is whether the timing changes implicit in this patch
will make the rare data-corrupting races in the existing snapshot code
more likely. (I'm working on a fix for these races, but the unfinished
patch is already several hundred lines long.)
It would be helpful if some people on this mailing list would test
this patch in various scenarios and report back.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (25 commits)
sound: convert "sound" subdirectory to UTF-8
MAINTAINERS: Add cxacru website/mailing list
include files: convert "include" subdirectory to UTF-8
general: convert "kernel" subdirectory to UTF-8
documentation: convert the Documentation directory to UTF-8
Convert the toplevel files CREDITS and MAINTAINERS to UTF-8.
remove broken URLs from net drivers' output
Magic number prefix consistency change to Documentation/magic-number.txt
trivial: s/i_sem /i_mutex/
fix file specification in comments
drivers/base/platform.c: fix small typo in doc
misc doc and kconfig typos
Remove obsolete fat_cvf help text
Fix occurrences of "the the "
Fix minor typoes in kernel/module.c
Kconfig: Remove reference to external mqueue library
Kconfig: A couple of grammatical fixes in arch/i386/Kconfig
Correct comments in genrtc.c to refer to correct /proc file.
Fix more "deprecated" spellos.
Fix "deprecated" typoes.
...
Fix trivial comment conflict in kernel/relay.c.
Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress. This
patch introduces such notifications and causes them to be used during
suspend and resume transitions. It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).
[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
flush_work(wq, work) doesn't need the first parameter, we can use cwq->wq
(this was possible from the very beginnig, I missed this). So we can unify
flush_work_keventd and flush_work.
Also, rename flush_work() to cancel_work_sync() and fix all callers.
Perhaps this is not the best name, but "flush_work" is really bad.
(akpm: this is why the earlier patches bypassed maintainers)
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Auke Kok <auke-jan.h.kok@intel.com>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
Display all possible partitions when the root filesystem is not mounted.
This helps to track spell'o's and missing drivers.
Updated to work with newer kernels.
Example output:
VFS: Cannot open root device "foobar" or unknown-block(0,0)
Please append a correct "root=" boot option; here are the available partitions:
0800 8388608 sda driver: sd
0801 192748 sda1
0802 8193150 sda2
0810 4194304 sdb driver: sd
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
[akpm@linux-foundation.org: cleanups, fix printk warnings]
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Cc: Dave Gilbert <linux@treblig.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix units mismatch (jiffies vs msecs) in as-iosched.c, spotted by Xiaoning
Ding <dingxn@cse.ohio-state.edu>.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I think we might just need the blk_map_kern users now. For the async
execute I added the bounce code already and the block SG_IO has it
atleady. I think the blk_map_kern bounce code got dropped because we
thought the correct gfp_t would be passed in. But I think all we need is
the patch below and all the paths are take care of. The patch is not
tested. Patch was made against scsi-misc.
The last place that is sending non sg commands may just be md/dm-emc.c
but that is is just waiting on alasdair to take some patches that fix
that and a bunch of junk in there including adding bounce support. If
the patch below is ok though and dm-emc finally gets converted then it
will have sg and bonce buffer support.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch provides a new macro
KMEM_CACHE(<struct>, <flags>)
to simplify slab creation. KMEM_CACHE creates a slab with the name of the
struct, with the size of the struct and with the alignment of the struct.
Additional slab flags may be specified if necessary.
Example
struct test_slab {
int a,b,c;
struct list_head;
} __cacheline_aligned_in_smp;
test_slab_cache = KMEM_CACHE(test_slab, SLAB_PANIC)
will create a new slab named "test_slab" of the size sizeof(struct
test_slab) and aligned to the alignment of test slab. If it fails then we
panic.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the destroy_dirty_buffers argument from invalidate_bdev(), it hasn't
been used in 6 years (so akpm says).
find * -name \*.[ch] | xargs grep -l invalidate_bdev |
while read file; do
quilt add $file;
sed -ie 's/invalidate_bdev(\([^,]*\),[^)]*)/invalidate_bdev(\1)/g' $file;
done
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need to work on cleaning up the relationship between kobjects, ksets and
ktypes. The removal of 'struct subsystem' is the first step of this,
especially as it is not really needed at all.
Thanks to Kay for fixing the bugs in this patch.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We often lookup the same queue many times in succession, so cache
the last looked up queue to avoid browsing the rbtree.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
cfq hash is no more necessary. We always can get cfqq from io context.
cfq_get_io_context_noalloc() function is introduced, because we don't
want to allocate cic on merging and checking may_queue. In order to
identify sync queue we've used hash key = CFQ_KEY_ASYNC. Since hash is
eliminated we need to use other criterion: sync flag for queue is added.
In all places where we dig in rb_tree we're in current context, so no
additional locking is required.
Advantages of this patch: no additional memory for hash, no seeking in
hash, code is cleaner. But it is necessary now to seek cic in per-ioc
rbtree, but it is faster:
- most processes work only with few devices
- most systems have only few block devices
- it is a rb-tree
Signed-off-by: Vasily Tarasov <vtaras@openvz.org>
Changes by me:
- Merge into CFQ devel branch
- Get rid of cfq_get_io_context_noalloc()
- Fix various bugs with dereferencing cic->cfqq[] with offset other
than 0 or 1.
- Fix bug in cfqq setup, is_sync condition was reversed.
- Fix bug where only bio_sync() is used, we need to check for a READ too
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
For tagged devices, allow overlap of requests if the idle window
isn't enabled on the current active queue.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
It's only used for preemption now that the IDLE and RT queues also
use the rbtree. If we pass an 'add_front' variable to
cfq_service_tree_add(), we can set ->rb_key to 0 to force insertion
at the front of the tree.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
