Commit Graph

187 Commits

Author SHA1 Message Date
Artem Bityutskiy
0d5c3eba2e vfs: nuke pdflush from comments
The pdflush thread is long gone, so this patch removes references to pdflush
from vfs comments.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-04 12:15:37 +04:00
Linus Torvalds
0d167518e0 Merge branch 'for-3.5/core' of git://git.kernel.dk/linux-block
Merge block/IO core bits from Jens Axboe:
 "This is a bit bigger on the core side than usual, but that is purely
  because we decided to hold off on parts of Tejun's submission on 3.4
  to give it a bit more time to simmer.  As a consequence, it's seen a
  long cycle in for-next.

  It contains:

   - Bug fix from Dan, wrong locking type.
   - Relax splice gifting restriction from Eric.
   - A ton of updates from Tejun, primarily for blkcg.  This improves
     the code a lot, making the API nicer and cleaner, and also includes
     fixes for how we handle and tie policies and re-activate on
     switches.  The changes also include generic bug fixes.
   - A simple fix from Vivek, along with a fix for doing proper delayed
     allocation of the blkcg stats."

Fix up annoying conflict just due to different merge resolution in
Documentation/feature-removal-schedule.txt

* 'for-3.5/core' of git://git.kernel.dk/linux-block: (92 commits)
  blkcg: tg_stats_alloc_lock is an irq lock
  vmsplice: relax alignement requirements for SPLICE_F_GIFT
  blkcg: use radix tree to index blkgs from blkcg
  blkcg: fix blkcg->css ref leak in __blkg_lookup_create()
  block: fix elvpriv allocation failure handling
  block: collapse blk_alloc_request() into get_request()
  blkcg: collapse blkcg_policy_ops into blkcg_policy
  blkcg: embed struct blkg_policy_data in policy specific data
  blkcg: mass rename of blkcg API
  blkcg: style cleanups for blk-cgroup.h
  blkcg: remove blkio_group->path[]
  blkcg: blkg_rwstat_read() was missing inline
  blkcg: shoot down blkgs if all policies are deactivated
  blkcg: drop stuff unused after per-queue policy activation update
  blkcg: implement per-queue policy activation
  blkcg: add request_queue->root_blkg
  blkcg: make request_queue bypassing on allocation
  blkcg: make sure blkg_lookup() returns %NULL if @q is bypassing
  blkcg: make blkg_conf_prep() take @pol and return with queue lock held
  blkcg: remove static policy ID enums
  ...
2012-05-30 08:52:42 -07:00
Bernd Schubert
f908ee9463 bio allocation failure due to bio_get_nr_vecs()
The number of bio_get_nr_vecs() is passed down via bio_alloc() to
bvec_alloc_bs(), which fails the bio allocation if
nr_iovecs > BIO_MAX_PAGES. For the underlying caller this causes an
unexpected bio allocation failure.
Limiting to queue_max_segments() is not sufficient, as max_segments
also might be very large.

bvec_alloc_bs(gfp_mask, nr_iovecs, ) => NULL when nr_iovecs  > BIO_MAX_PAGES
bio_alloc_bioset(gfp_mask, nr_iovecs, ...)
bio_alloc(GFP_NOIO, nvecs)
xfs_alloc_ioend_bio()

Signed-off-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-11 16:45:12 +02:00
Tejun Heo
959d851caa Merge branch 'for-3.5' of ../cgroup into block/for-3.5/core-merged
cgroup/for-3.5 contains the following changes which blk-cgroup needs
to proceed with the on-going cleanup.

* Dynamic addition and removal of cftypes to make config/stat file
  handling modular for policies.

* cgroup removal update to not wait for css references to drain to fix
  blkcg removal hang caused by cfq caching cfqgs.

Pull in cgroup/for-3.5 into block/for-3.5/core.  This causes the
following conflicts in block/blk-cgroup.c.

* 761b3ef50e "cgroup: remove cgroup_subsys argument from callbacks"
  conflicts with blkiocg_pre_destroy() addition and blkiocg_attach()
  removal.  Resolved by removing @subsys from all subsys methods.

* 676f7c8f84 "cgroup: relocate cftype and cgroup_subsys definitions in
  controllers" conflicts with ->pre_destroy() and ->attach() updates
  and removal of modular config.  Resolved by dropping forward
  declarations of the methods and applying updates to the relocated
  blkio_subsys.

* 4baf6e3325 "cgroup: convert all non-memcg controllers to the new
  cftype interface" builds upon the previous item.  Resolved by adding
  ->base_cftypes to the relocated blkio_subsys.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 12:55:00 -07:00
Tejun Heo
852c788f83 block: implement bio_associate_current()
IO scheduling and cgroup are tied to the issuing task via io_context
and cgroup of %current.  Unfortunately, there are cases where IOs need
to be routed via a different task which makes scheduling and cgroup
limit enforcement applied completely incorrectly.

For example, all bios delayed by blk-throttle end up being issued by a
delayed work item and get assigned the io_context of the worker task
which happens to serve the work item and dumped to the default block
cgroup.  This is double confusing as bios which aren't delayed end up
in the correct cgroup and makes using blk-throttle and cfq propio
together impossible.

Any code which punts IO issuing to another task is affected which is
getting more and more common (e.g. btrfs).  As both io_context and
cgroup are firmly tied to task including userland visible APIs to
manipulate them, it makes a lot of sense to match up tasks to bios.

This patch implements bio_associate_current() which associates the
specified bio with %current.  The bio will record the associated ioc
and blkcg at that point and block layer will use the recorded ones
regardless of which task actually ends up issuing the bio.  bio
release puts the associated ioc and blkcg.

It grabs and remembers ioc and blkcg instead of the task itself
because task may already be dead by the time the bio is issued making
ioc and blkcg inaccessible and those are all block layer cares about.

elevator_set_req_fn() is updated such that the bio elvdata is being
allocated for is available to the elevator.

This doesn't update block cgroup policies yet.  Further patches will
implement the support.

-v2: #ifdef CONFIG_BLK_CGROUP added around bio->bi_ioc dereference in
     rq_ioc() to fix build breakage.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Kent Overstreet <koverstreet@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-06 21:27:24 +01:00
Paul Gortmaker
630d9c4727 fs: reduce the use of module.h wherever possible
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include.  Fix up any implicit
include dependencies that were being masked by module.h along
the way.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-28 19:31:58 -05:00
Kent Overstreet
5abebfdd02 bio: don't overflow in bio_get_nr_vecs()
There were two places bio_get_nr_vecs() could overflow:

First, it did a left shift to convert from sectors to bytes immediately
before dividing by PAGE_SIZE.  If PAGE_SIZE ever was less than 512 a great
many things would break, so dividing by PAGE_SIZE >> 9 is safe and will
generate smaller code too.

The nastier overflow was in the DIV_ROUND_UP() (that's what the code was
effectively doing, anyways).  If n + d overflowed, the whole thing would
return 0 which breaks things rather effectively.

bio_get_nr_vecs() doesn't claim to give an exact value anyways, so the
DIV_ROUND_UP() is silly; we could do a straight divide except if a
device's queue_max_sectors was less than PAGE_SIZE we'd return 0.  So we
just add 1; this should always be safe - things will break badly if
bio_get_nr_vecs() returns > BIO_MAX_PAGES (bio_alloc() will suddenly start
failing) but it's queue_max_segments that must guard against this, if
queue_max_sectors is preventing this from happen things are going to
explode on architectures with different PAGE_SIZE.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Tejun Heo <tj@kernel.org>
Acked-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-08 22:07:18 +01:00
Dan Carpenter
121f099412 bio: change some signed vars to unsigned
This is just a cleanup patch to silence a static checker warning.

The problem is that we cap "nr_iovecs" so it can't be larger than
"UIO_MAXIOV" but we don't check for negative values.  It turns out this is
prevented at other layers, but logically it doesn't make sense to have
negative nr_iovecs so making it unsigned is nicer.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-11-16 09:21:50 +01:00
Tao Ma
9562ad9ab3 block: Remove the control of complete cpu from bio.
bio originally has the functionality to set the complete cpu, but
it is broken.

Chirstoph said that "This code is unused, and from the all the
discussions lately pretty obviously broken.  The only thing keeping
it serves is creating more confusion and possibly more bugs."

And Jens replied with "We can kill bio_set_completion_cpu(). I'm fine
with leaving cpu control to the request based drivers, they are the
only ones that can toggle the setting anyway".

So this patch tries to remove all the work of controling complete cpu
from a bio.

Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-24 16:11:30 +02:00
Andreas Gruenbacher
c642808454 vfs: Improve the bio_add_page() and bio_add_pc_page() descriptions
The descriptions of bio_add_page() and bio_add_pc_page() are slightly
inconsistent; improve them.

Signed-off-by: Andreas Gruenbacher <agruen@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-27 09:43:00 -04:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Linus Torvalds
6c51038900 Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits)
  Documentation/iostats.txt: bit-size reference etc.
  cfq-iosched: removing unnecessary think time checking
  cfq-iosched: Don't clear queue stats when preempt.
  blk-throttle: Reset group slice when limits are changed
  blk-cgroup: Only give unaccounted_time under debug
  cfq-iosched: Don't set active queue in preempt
  block: fix non-atomic access to genhd inflight structures
  block: attempt to merge with existing requests on plug flush
  block: NULL dereference on error path in __blkdev_get()
  cfq-iosched: Don't update group weights when on service tree
  fs: assign sb->s_bdi to default_backing_dev_info if the bdi is going away
  block: Require subsystems to explicitly allocate bio_set integrity mempool
  jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
  jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
  fs: make fsync_buffers_list() plug
  mm: make generic_writepages() use plugging
  blk-cgroup: Add unaccounted time to timeslice_used.
  block: fixup plugging stubs for !CONFIG_BLOCK
  block: remove obsolete comments for blkdev_issue_zeroout.
  blktrace: Use rq->cmd_flags directly in blk_add_trace_rq.
  ...

Fix up conflicts in fs/{aio.c,super.c}
2011-03-24 10:16:26 -07:00
Mandeep Singh Baines
80cdc6dae7 fs: use appropriate printk priority levels
printk()s without a priority level default to KERN_WARNING.  To reduce
noise at KERN_WARNING, this patch set the priority level appriopriately
for unleveled printks()s.  This should be useful to folks that look at
dmesg warnings closely.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:10 -07:00
Martin K. Petersen
a91a2785b2 block: Require subsystems to explicitly allocate bio_set integrity mempool
MD and DM create a new bio_set for every metadevice. Each bio_set has an
integrity mempool attached regardless of whether the metadevice is
capable of passing integrity metadata. This is a waste of memory.

Instead we defer the allocation decision to MD and DM since we know at
metadevice creation time whether integrity passthrough is needed or not.

Automatic integrity mempool allocation can then be removed from
bioset_create() and we make an explicit integrity allocation for the
fs_bio_set.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Acked-by: Mike Snitzer <snizer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-17 11:11:05 +01:00
Martin K. Petersen
df67714028 block: biovec_slab vs. CONFIG_BLK_DEV_INTEGRITY
The block integrity subsystem no longer uses the bio_vec slabs so this
code can safely be compiled in.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-08 08:28:01 +01:00
Jens Axboe
cb4644cac4 bio: take care not overflow page count when mapping/copying user data
If the iovec is being set up in a way that causes uaddr + PAGE_SIZE
to overflow, we could end up attempting to map a huge number of
pages. Check for this invalid input type.

Reported-by: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-10 14:40:43 +01:00
Jens Axboe
f3f63c1c28 block: limit vec count in bio_kmalloc() and bio_alloc_map_data()
Reported-by: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-10 14:40:42 +01:00
Christoph Hellwig
7b6d91daee block: unify flags for struct bio and struct request
Remove the current bio flags and reuse the request flags for the bio, too.
This allows to more easily trace the type of I/O from the filesystem
down to the block driver.  There were two flags in the bio that were
missing in the requests:  BIO_RW_UNPLUG and BIO_RW_AHEAD.  Also I've
renamed two request flags that had a superflous RW in them.

Note that the flags are in bio.h despite having the REQ_ name - as
blkdev.h includes bio.h that is the only way to go for now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:20:39 +02:00
Jens Axboe
b4b7a4ef09 Merge branch 'master' into for-linus
Conflicts:
	block/Kconfig

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-03-19 08:05:10 +01:00
Jiri Kosina
318ae2edc3 Merge branch 'for-next' into for-linus
Conflicts:
	Documentation/filesystems/proc.txt
	arch/arm/mach-u300/include/mach/debug-macro.S
	drivers/net/qlge/qlge_ethtool.c
	drivers/net/qlge/qlge_main.c
	drivers/net/typhoon.c
2010-03-08 16:55:37 +01:00
Dmitry Monakhov
8bf8c376ab blkdev: fix merge_bvec_fn return value checks v2
merge_bvec_fn() returns bvec->bv_len on success. So we have to check
against this value. But in case of fs_optimization merge we compare
with wrong value. This patch must be included in
 b428cd6da7e6559aca69aa2e3a526037d3f20403
But accidentally i've forgot to add this in the initial patch.
To make things straight let's replace all such checks.
In fact this makes code easy to understand.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-03-08 09:10:38 +01:00
Jens Axboe
9599945bac Revert "blkdev: fix merge_bvec_fn return value checks"
This reverts commit 9f7cdbc33f.

It's causing oopses om dm setups, so revert it until we investigate.

Reported-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-03-02 19:17:34 +01:00
Dmitry Monakhov
9f7cdbc33f blkdev: fix merge_bvec_fn return value checks
merge_bvec_fn() returns bvec->bv_len on success. So we have to check
against this value. But in case of fs_optimization merge we compare
with wrong value. This patch must be included in
 b428cd6da7e6559aca69aa2e3a526037d3f20403
But accidentally i've forgot to add this in the initial patch.
To make things straight let's replace all such checks.
In fact this makes code easy to understand.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-02-28 19:47:18 +01:00
Martin K. Petersen
8a78362c4e block: Consolidate phys_segment and hw_segment limits
Except for SCSI no device drivers distinguish between physical and
hardware segment limits.  Consolidate the two into a single segment
limit.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-02-26 13:58:08 +01:00
Jaak Ristioja
db18efac0b bio: Fix outdated comment about bio_alloc_bioset()
In commit 451a9ebf65 bio_alloc_bioset()
was refactored not to take NULL as a valid argument for bs. This patch
changes the comment for that function accordingly. Currently, passing
NULL as argument to parameter bs would result in a NULL pointer
dereference.

Signed-off-by: Jaak Ristioja <ristioja@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-05 12:22:36 +01:00
Dmitry Monakhov
1d6165851c block: fix bio_add_page for non trivial merge_bvec_fn case
We have to properly decrease bi_size in order to merge_bvec_fn return
right result.  Otherwise this result in false merge rejects for two
absolutely valid bio_vecs.  This may cause significant performance
penalty for example fs_block_size == 1k and block device is raid0 with
small chunk_size = 8k. Then it is impossible to merge 7-th fs-block in
to bio which already has 6 fs-blocks.

Cc: <stable@kernel.org>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-01-28 15:08:29 +01:00
Thiago Farina
f06f135d86 fs/bio.c: fix shadows sparse warning
fs/bio.c:81:33: warning: symbol 'bslab' shadows an earlier one
fs/bio.c:74:25: originally declared here

Signed-off-by: Thiago Farina <tfransosi@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-01-19 14:07:09 +01:00
Linus Torvalds
4ef58d4e2a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (42 commits)
  tree-wide: fix misspelling of "definition" in comments
  reiserfs: fix misspelling of "journaled"
  doc: Fix a typo in slub.txt.
  inotify: remove superfluous return code check
  hdlc: spelling fix in find_pvc() comment
  doc: fix regulator docs cut-and-pasteism
  mtd: Fix comment in Kconfig
  doc: Fix IRQ chip docs
  tree-wide: fix assorted typos all over the place
  drivers/ata/libata-sff.c: comment spelling fixes
  fix typos/grammos in Documentation/edac.txt
  sysctl: add missing comments
  fs/debugfs/inode.c: fix comment typos
  sgivwfb: Make use of ARRAY_SIZE.
  sky2: fix sky2_link_down copy/paste comment error
  tree-wide: fix typos "couter" -> "counter"
  tree-wide: fix typos "offest" -> "offset"
  fix kerneldoc for set_irq_msi()
  spidev: fix double "of of" in comment
  comment typo fix: sybsystem -> subsystem
  ...
2009-12-09 19:43:33 -08:00
André Goddard Rosa
af901ca181 tree-wide: fix assorted typos all over the place
That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperature"
, "channel", "[un]used", "application", "example","hierarchy", "therefore"
, "[over|under]flow", "contiguous", "threshold", "enough" and others.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-04 15:39:55 +01:00
Ilya Loginov
2d4dc890b5 block: add helpers to run flush_dcache_page() against a bio and a request's pages
Mtdblock driver doesn't call flush_dcache_page for pages in request.  So,
this causes problems on architectures where the icache doesn't fill from
the dcache or with dcache aliases.  The patch fixes this.

The ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE symbol was introduced to avoid
pointless empty cache-thrashing loops on architectures for which
flush_dcache_page() is a no-op.  Every architecture was provided with this
flush pages on architectires where ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE is
equal 1 or do nothing otherwise.

See "fix mtd_blkdevs problem with caches on some architectures" discussion
on LKML for more information.

Signed-off-by: Ilya Loginov <isloginov@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Peter Horton <phorton@bitbox.co.uk>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-11-26 09:16:19 +01:00
Alberto Bertogli
5f04eeb8a7 Fix bio_alloc() and bio_kmalloc() documentation
Commit 451a9ebf accidentally broke bio_alloc() and bio_kmalloc() comments by
(almost) swapping them.

This patch fixes that, by placing the comments in the right place.

Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-11-02 11:41:13 +01:00
Alberto Bertogli
ad0bf11070 bio_put(): add bio_clone() to the list of functions in the comment
In bio_put()'s comment, add bio_clone() to the list of functions that can
give you a bio reference.

Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-11-02 11:39:22 +01:00
H Hartley Sweeten
a112a71d45 fs/bio.c: move EXPORT* macros to line after function
As mentioned in Documentation/CodingStyle, move EXPORT* macro's
to the line immediately after the closing function brace line.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-01 21:15:46 +02:00
FUJITA Tomonori
ecb554a846 block: fix sg SG_DXFER_TO_FROM_DEV regression
I overlooked SG_DXFER_TO_FROM_DEV support when I converted sg to use
the block layer mapping API (2.6.28).

Douglas Gilbert explained SG_DXFER_TO_FROM_DEV:

http://www.spinics.net/lists/linux-scsi/msg37135.html

=
The semantics of SG_DXFER_TO_FROM_DEV were:
   - copy user space buffer to kernel (LLD) buffer
   - do SCSI command which is assumed to be of the DATA_IN
     (data from device) variety. This would overwrite
     some or all of the kernel buffer
   - copy kernel (LLD) buffer back to the user space.

The idea was to detect short reads by filling the original
user space buffer with some marker bytes ("0xec" it would
seem in this report). The "resid" value is a better way
of detecting short reads but that was only added this century
and requires co-operation from the LLD.
=

This patch changes the block layer mapping API to support this
semantics. This simply adds another field to struct rq_map_data and
enables __bio_copy_iov() to copy data from user space even with READ
requests.

It's better to add the flags field and kills null_mapped and the new
from_user fields in struct rq_map_data but that approach makes it
difficult to send this patch to stable trees because st and osst
drivers use struct rq_map_data (they were converted to use the block
layer in 2.6.29 and 2.6.30). Well, I should clean up the block layer
mapping API.

zhou sf reported this regiression and tested this patch:

http://www.spinics.net/lists/linux-scsi/msg37128.html
http://www.spinics.net/lists/linux-scsi/msg37168.html

Reported-by: zhou sf <sxzzsf@gmail.com>
Tested-by: zhou sf <sxzzsf@gmail.com>
Cc: stable@kernel.org
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-07-10 20:31:53 +02:00
Martin K. Petersen
7878cba9f0 block: Create bip slabs with embedded integrity vectors
This patch restores stacking ability to the block layer integrity
infrastructure by creating a set of dedicated bip slabs.  Each bip slab
has an embedded bio_vec array at the end.  This cuts down on memory
allocations and also simplifies the code compared to the original bvec
version.  Only the largest bip slab is backed by a mempool.  The pool is
contained in the bio_set so stacking drivers can ensure forward
progress.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@carl.(none)>
2009-07-01 10:56:25 +02:00
Li Zefan
e212d6f250 block: remove some includings of blktrace_api.h
When porting blktrace to tracepoints, we changed to trace/block.h
for trace prober declarations.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-06-16 11:19:36 +02:00
Nikanth Karthikesan
76d93ff344 trivial: fix typo in bio_alloc kernel doc
Fix typo in bio_alloc kernel doc.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-06-12 18:01:47 +02:00
Linus Torvalds
c9059598ea Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block: (153 commits)
  block: add request clone interface (v2)
  floppy: fix hibernation
  ramdisk: remove long-deprecated "ramdisk=" boot-time parameter
  fs/bio.c: add missing __user annotation
  block: prevent possible io_context->refcount overflow
  Add serial number support for virtio_blk, V4a
  block: Add missing bounce_pfn stacking and fix comments
  Revert "block: Fix bounce limit setting in DM"
  cciss: decode unit attention in SCSI error handling code
  cciss: Remove no longer needed sendcmd reject processing code
  cciss: change SCSI error handling routines to work with interrupts enabled.
  cciss: separate error processing and command retrying code in sendcmd_withirq_core()
  cciss: factor out fix target status processing code from sendcmd functions
  cciss: simplify interface of sendcmd() and sendcmd_withirq()
  cciss: factor out core of sendcmd_withirq() for use by SCSI error handling code
  cciss: Use schedule_timeout_uninterruptible in SCSI error handling code
  block: needs to set the residual length of a bidi request
  Revert "block: implement blkdev_readpages"
  block: Fix bounce limit setting in DM
  Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt
  ...

Manually fix conflicts with tracing updates in:
	block/blk-sysfs.c
	drivers/ide/ide-atapi.c
	drivers/ide/ide-cd.c
	drivers/ide/ide-floppy.c
	drivers/ide/ide-tape.c
	include/trace/events/block.h
	kernel/trace/blktrace.c
2009-06-11 11:10:35 -07:00
Michal Simek
0e0c62123b fs/bio.c: add missing __user annotation
As reported by sparse:

fs/bio.c:720:13: warning: incorrect type in assignment (different address spaces)
fs/bio.c:720:13:    expected char *iov_addr
fs/bio.c:720:13:    got void [noderef] <asn:1>*
fs/bio.c:724:36: warning: incorrect type in argument 2 (different address spaces)
fs/bio.c:724:36:    expected void const [noderef] <asn:1>*from
fs/bio.c:724:36:    got char *iov_addr

Signed-off-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-06-10 23:07:15 +02:00
Li Zefan
55782138e4 tracing/events: convert block trace points to TRACE_EVENT()
TRACE_EVENT is a more generic way to define tracepoints. Doing so adds
these new capabilities to this tracepoint:

  - zero-copy and per-cpu splice() tracing
  - binary tracing without printf overhead
  - structured logging records exposed under /debug/tracing/events
  - trace events embedded in function tracer output and other plugins
  - user-defined, per tracepoint filter expressions
  ...

Cons:

  - no dev_t info for the output of plug, unplug_timer and unplug_io events.
    no dev_t info for getrq and sleeprq events if bio == NULL.
    no dev_t info for rq_abort,...,rq_requeue events if rq->rq_disk == NULL.

    This is mainly because we can't get the deivce from a request queue.
    But this may change in the future.

  - A packet command is converted to a string in TP_assign, not TP_print.
    While blktrace do the convertion just before output.

    Since pc requests should be rather rare, this is not a big issue.

  - In blktrace, an event can have 2 different print formats, but a TRACE_EVENT
    has a unique format, which means we have some unused data in a trace entry.

    The overhead is minimized by using __dynamic_array() instead of __array().

I've benchmarked the ioctl blktrace vs the splice based TRACE_EVENT tracing:

      dd                   dd + ioctl blktrace       dd + TRACE_EVENT (splice)
1     7.36s, 42.7 MB/s     7.50s, 42.0 MB/s          7.41s, 42.5 MB/s
2     7.43s, 42.3 MB/s     7.48s, 42.1 MB/s          7.43s, 42.4 MB/s
3     7.38s, 42.6 MB/s     7.45s, 42.2 MB/s          7.41s, 42.5 MB/s

So the overhead of tracing is very small, and no regression when using
those trace events vs blktrace.

And the binary output of TRACE_EVENT is much smaller than blktrace:

 # ls -l -h
 -rw-r--r-- 1 root root 8.8M 06-09 13:24 sda.blktrace.0
 -rw-r--r-- 1 root root 195K 06-09 13:24 sda.blktrace.1
 -rw-r--r-- 1 root root 2.7M 06-09 13:25 trace_splice.out

Following are some comparisons between TRACE_EVENT and blktrace:

plug:
  kjournald-480   [000]   303.084981: block_plug: [kjournald]
  kjournald-480   [000]   303.084981:   8,0    P   N [kjournald]

unplug_io:
  kblockd/0-118   [000]   300.052973: block_unplug_io: [kblockd/0] 1
  kblockd/0-118   [000]   300.052974:   8,0    U   N [kblockd/0] 1

remap:
  kjournald-480   [000]   303.085042: block_remap: 8,0 W 102736992 + 8 <- (8,8) 33384
  kjournald-480   [000]   303.085043:   8,0    A   W 102736992 + 8 <- (8,8) 33384

bio_backmerge:
  kjournald-480   [000]   303.085086: block_bio_backmerge: 8,0 W 102737032 + 8 [kjournald]
  kjournald-480   [000]   303.085086:   8,0    M   W 102737032 + 8 [kjournald]

getrq:
  kjournald-480   [000]   303.084974: block_getrq: 8,0 W 102736984 + 8 [kjournald]
  kjournald-480   [000]   303.084975:   8,0    G   W 102736984 + 8 [kjournald]

  bash-2066  [001]  1072.953770:   8,0    G   N [bash]
  bash-2066  [001]  1072.953773: block_getrq: 0,0 N 0 + 0 [bash]

rq_complete:
  konsole-2065  [001]   300.053184: block_rq_complete: 8,0 W () 103669040 + 16 [0]
  konsole-2065  [001]   300.053191:   8,0    C   W 103669040 + 16 [0]

  ksoftirqd/1-7   [001]  1072.953811:   8,0    C   N (5a 00 08 00 00 00 00 00 24 00) [0]
  ksoftirqd/1-7   [001]  1072.953813: block_rq_complete: 0,0 N (5a 00 08 00 00 00 00 00 24 00) 0 + 0 [0]

rq_insert:
  kjournald-480   [000]   303.084985: block_rq_insert: 8,0 W 0 () 102736984 + 8 [kjournald]
  kjournald-480   [000]   303.084986:   8,0    I   W 102736984 + 8 [kjournald]

Changelog from v2 -> v3:

- use the newly introduced __dynamic_array().

Changelog from v1 -> v2:

- use __string() instead of __array() to minimize the memory required
  to store hex dump of rq->cmd().

- support large pc requests.

- add missing blk_fill_rwbs_rq() in block_rq_requeue TRACE_EVENT.

- some cleanups.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A2DF669.5070905@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-06-09 12:34:23 -04:00
Martin K. Petersen
ae03bf639a block: Use accessor functions for queue limits
Convert all external users of queue limits to using wrapper functions
instead of poking the request queue variables directly.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:54 +02:00
Martin K. Petersen
e1defc4ff0 block: Do away with the notion of hardsect_size
Until now we have had a 1:1 mapping between storage device physical
block size and the logical block sized used when addressing the device.
With SATA 4KB drives coming out that will no longer be the case.  The
sector size will be 4KB but the logical block size will remain
512-bytes.  Hence we need to distinguish between the physical block size
and the logical ditto.

This patch renames hardsect_size to logical_block_size.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:54 +02:00
Jens Axboe
e4b636366c Merge branch 'master' into for-2.6.31
Conflicts:
	drivers/block/hd.c
	drivers/block/mg_disk.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 20:25:34 +02:00
Tejun Heo
4fc981ef9e bio: always copy back data for copied kernel requests
When a read bio_copy_kern() request fails, the content of the bounce
buffer is not copied back.  However, as request failure doesn't
necessarily mean complete failure, the buffer state can be useful.
This behavior is also inconsistent with the user map counterpart and
causes the subtle difference between bounced and unbounced IO causes
confusion.

This patch makes bio_copy_kern_endio() ignore @err and always copy
back data on request completion.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-19 11:36:08 +02:00
FUJITA Tomonori
69838727bc bio: fix memcpy corruption in bio_copy_user_iov()
st driver uses blk_rq_map_user() in order to just build a request out
of page frames. In this case, map_data->offset is a non zero value and
iov[0].iov_base is NULL. We need to increase nr_pages for that.

Cc: stable@kernel.org
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-28 20:24:29 +02:00
Tejun Heo
a9e9dc24bb bio: use bio_kmalloc() in copy/map functions
Impact: remove possible deadlock condition

There is no reason to use mempool backed allocation for map functions.
Also, because kern mapping is used inside LLDs (e.g. for EH), using
mempool backed allocation can lead to deadlock under extreme
conditions (mempool already consumed by the time a request reached EH
and requests are blocked on EH).

Switch copy/map functions to bio_kmalloc().

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-22 08:35:10 +02:00
Tejun Heo
451a9ebf65 bio: fix bio_kmalloc()
Impact: fix bio_kmalloc() and its destruction path

bio_kmalloc() was broken in two ways.

* bvec_alloc_bs() first allocates bvec using kmalloc() and then
  ignores it and allocates again like non-kmalloc bvecs.

* bio_kmalloc_destructor() didn't check for and free bio integrity
  data.

This patch fixes the above problems.  kmalloc patch is separated out
from bio_alloc_bioset() and allocates the requested number of bvecs as
inline bvecs.

* bio_alloc_bioset() no longer takes NULL @bs.  None other than
  bio_kmalloc() used it and outside users can't know how it was
  allocated anyway.

* Define and use BIO_POOL_NONE so that pool index check in
  bvec_free_bs() triggers if inline or kmalloc allocated bvec gets
  there.

* Relocate destructors on top of each allocation function so that how
  they're used is more clear.

Jens Axboe suggested allocating bvecs inline.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-22 08:35:10 +02:00
Jens Axboe
86c824b943 bio: add documentation to bio_alloc()
Explain that with __GFP_WAIT set it will not fail, and that the caller
must never allocate more than 1 bio at the time.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 12:10:12 +02:00
Alberto Bertogli
c7eee1b836 trivial: Fix typo in bio_split()'s documentation
Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-03-30 15:22:02 +02:00
Martin K. Petersen
6d2a78e783 block: add private bio_set for bio integrity allocations
The integrity bio allocation needs its own bio_set to avoid violating
the mempool allocation rules and risking deadlocks.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-24 12:35:17 +01:00
Jens Axboe
a7fcd37cdc block: don't create bio_vec slabs of less than the inline number
If we don't have CONFIG_BLK_DEV_INTEGRITY set, then we don't have
any external dependencies on the bio_vec slabs. So don't create
the ones that we will inline anyway.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-24 12:35:16 +01:00
Ingo Molnar
34053979fb block: cleanup bio_alloc_bioset()
this warning (which got fixed by commit b2bf968):

  fs/bio.c: In function ‘bio_alloc_bioset’:
  fs/bio.c:305: warning: ‘p’ may be used uninitialized in this function

Triggered because the code flow in bio_alloc_bioset() is correct
but a bit complex for the compiler to see through.

Streamline it a bit - this also makes the code a tiny bit more compact:

   text	   data	    bss	    dec	    hex	filename
   7540	    256	     40	   7836	   1e9c	bio.o.before
   7539	    256	     40	   7835	   1e9b	bio.o.after

Also remove an older compiler-warnings annotation from this function,
it's not needed.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-24 12:35:16 +01:00
Li Zefan
059ea3318c block: fix memory leak in bio_clone()
If bio_integrity_clone() fails, bio_clone() returns NULL without freeing
the newly allocated bio.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-14 21:06:52 +01:00
un'ichi Nomura
87092698c6 block: Add gfp_mask parameter to bio_integrity_clone()
Stricter gfp_mask might be required for clone allocation.
For example, request-based dm may clone bio in interrupt context
so it has to use GFP_ATOMIC.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-14 21:06:51 +01:00
Jens Axboe
b2bf96833c block: fix bogus gcc warning for uninitialized var usage
Newer gcc throw this warning:

        fs/bio.c: In function ?bio_alloc_bioset?:
        fs/bio.c:305: warning: ?p? may be used uninitialized in this function

since it cannot figure out that 'p' is only ever used if 'bs' is non-NULL.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-02-26 10:45:48 +01:00
Subhash Peddamallu
a60e78e57a fs/bio: bio_alloc_bioset: pass right object ptr to mempool_free
When freeing from bio pool use right ptr to account for bs->front_pad,
instead of bio ptr,

Signed-off-by: Subhash Peddamallu <subhash.peddamallu@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-02-18 10:32:01 +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
FUJITA Tomonori
e623ddb4e9 [SCSI] block: fix bio_add_page misuse with rq_map_data
This fixes bio_add_page misuse in bio_copy_user_iov with rq_map_data,
which only sg uses now.

rq_map_data carries page frames for bio_add_pc_page. bio_copy_user_iov
uses bio_add_pc_page with a larger size than PAGE_SIZE. It's clearly
wrong.

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 11:09:41 -06:00
Jens Axboe
d3f761104b bio: get rid of bio_vec clearing
We don't need to clear the memory used for adding bio_vec entries,
since nobody should be looking at members unitialized. Any valid
use should be below bio->bi_vcnt, and that members up until that count
must be valid since they were added through bio_add_page().

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:29:53 +01:00
Jens Axboe
392ddc3298 bio: add support for inlining a number of bio_vecs inside the bio
When we go and allocate a bio for IO, we actually do two allocations.
One for the bio itself, and one for the bi_io_vec that holds the
actual pages we are interested in.

This feature inlines a definable amount of io vecs inside the bio
itself, so we eliminate the bio_vec array allocation for IO's up
to a certain size. It defaults to 4 vecs, which is typically 16k
of IO.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:29:50 +01:00
Jens Axboe
bb799ca020 bio: allow individual slabs in the bio_set
Instead of having a global bio slab cache, add a reference to one
in each bio_set that is created. This allows for personalized slabs
in each bio_set, so that they can have bios of different sizes.

This means we can personalize the bios we return. File systems may
want to embed the bio inside another structure, to avoid allocation
more items (and stuffing them in ->bi_private) after the get a bio.
Or we may want to embed a number of bio_vecs directly at the end
of a bio, to avoid doing two allocations to return a bio. This is now
possible.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:29:23 +01:00
Jens Axboe
1b43449869 bio: move the slab pointer inside the bio_set
In preparation for adding differently sized bios.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:46 +01:00
Jens Axboe
7ff9345ffa bio: only mempool back the largest bio_vec slab cache
We only very rarely need the mempool backing, so it makes sense to
get rid of all but one of the mempool in a bio_set. So keep the
largest bio_vec count mempool so we can always honor the largest
allocation, and "upgrade" callers that fail.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:46 +01:00
Ingo Molnar
0bfc24559d blktrace: port to tracepoints, update
Port to the new tracepoints API: split DEFINE_TRACE() and DECLARE_TRACE()
sites. Spread them out to the usage sites, as suggested by
Mathieu Desnoyers.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
2008-11-26 13:04:35 +01:00
Arnaldo Carvalho de Melo
5f3ea37c77 blktrace: port to tracepoints
This was a forward port of work done by Mathieu Desnoyers, I changed it to
encode the 'what' parameter on the tracepoint name, so that one can register
interest in specific events and not on classes of events to then check the
'what' parameter.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-26 12:13:34 +01:00
Denis ChengRq
6feef531f5 block: mark bio_split_pool static
Since all bio_split calls refer the same single bio_split_pool, the bio_split
function can use bio_split_pool directly instead of the mempool_t parameter;

then the mempool_t parameter can be removed from bio_split param list, and
bio_split_pool is only referred in fs/bio.c file, can be marked static.

Signed-off-by: Denis ChengRq <crquan@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:57:05 +02:00
Martin K. Petersen
ad3316bf4e block: Find bio sector offset given idx and offset
Helper function to find the sector offset in a bio given bvec index
and page offset.

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
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
FUJITA Tomonori
818827669d block: make blk_rq_map_user take a NULL user-space buffer
This patch changes blk_rq_map_user to accept a NULL user-space buffer
with a READ command if rq_map_data is not NULL. Thus a caller can pass
page frames to lk_rq_map_user to just set up a request and bios with
page frames propely. bio_uncopy_user (called via blk_rq_unmap_user)
doesn't copy data to user space with such request.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:11 +02:00
FUJITA Tomonori
4d8ab62e08 bio: convert bio_copy_kern to use bio_copy_user
bio_copy_kern and bio_copy_user are very similar. This converts
bio_copy_kern to use bio_copy_user.

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 08:56:10 +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
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
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
Mikulas Patocka
b8b3e16cfe block: drop virtual merging accounting
Remove virtual merge accounting.

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
FUJITA Tomonori
aefcc28a3a bio: fix __bio_copy_iov() handling of bio->bv_len
The commit c5dec1c303 introduced
__bio_copy_iov() to add bounce support to blk_rq_map_user_iov.

__bio_copy_iov() uses bio->bv_len to copy data for READ commands after
the completion but it doesn't work with a request that partially
completed. SCSI always completes a PC request as a whole but seems
some don't.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-27 09:50:19 +02:00
FUJITA Tomonori
76029ff37f bio: fix bio_copy_kern() handling of bio->bv_len
The commit 68154e90c9 introduced
bio_copy_kern() to add bounce support to blk_rq_map_kern.

bio_copy_kern() uses bio->bv_len to copy data for READ commands after
the completion but it doesn't work with a request that partially
completed. SCSI always completes a PC request as a whole but seems
some don't.

This patch fixes bio_copy_kern to handle the above case. As
bio_copy_user does, bio_copy_kern uses struct bio_map_data to store
struct bio_vec.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reported-by: Nix <nix@esperi.org.uk>
Tested-by: Nix <nix@esperi.org.uk>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-27 09:50:19 +02:00
Denis ChengRq
1ac0ae062c bio: make use of bvec_nr_vecs
Since introduced in 7ba1ba12ee, it should be made use of.

Signed-off-by: Denis ChengRq <crquan@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-06 12:30:04 +02:00
Nick Piggin
f5dd33c494 dio: use get_user_pages_fast
Use get_user_pages_fast in the common/generic block and fs direct IO paths.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Reviewed-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>
2008-07-26 12:00:06 -07:00
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
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
Martin K. Petersen
51d654e1d8 block: Globalize bio_set and bio_vec_slab
Move struct bio_set and biovec_slab definitions to bio.h so they can
be used outside of bio.c.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:13 +02:00
Randy Dunlap
ffee0259c9 docbook: fix bio missing parameter
Fix fs/bio.c kernel-doc parameter warning:
Warning(linux-2.6.25-git14//fs/bio.c:972): No description found for parameter 'reading'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 18:35:03 +02:00
Jens Axboe
eeae1d48c0 block: use unitialized_var() in bio_alloc_bioset()
Better than setting idx to some random value and it silences the
same bogus gcc warning.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 13:26:27 +02:00
FUJITA Tomonori
68154e90c9 block: add dma alignment and padding support to blk_rq_map_kern
This patch adds bio_copy_kern similar to
bio_copy_user. blk_rq_map_kern uses bio_copy_kern instead of
bio_map_kern if necessary.

bio_copy_kern uses temporary pages and the bi_end_io callback frees
these pages. bio_copy_kern saves the original kernel buffer at
bio->bi_private it doesn't use something like struct bio_map_data to
store the information about the caller.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 09:50:34 +02:00
FUJITA Tomonori
c5dec1c303 block: convert bio_copy_user to bio_copy_user_iov
This patch enables bio_copy_user to take struct sg_iovec (renamed
bio_copy_user_iov). bio_copy_user uses bio_copy_user_iov internally as
bio_map_user uses bio_map_user_iov.

The major changes are:

- adds sg_iovec array to struct bio_map_data

- adds __bio_copy_iov that copy data between bio and
sg_iovec. bio_copy_user_iov and bio_uncopy_user use it.

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
Jens Axboe
40044ce0bf Revert "unexport bio_{,un}map_user"
Outside users like asmlib uses the mapping functions. API wise, the
export is definitely sane. It's a better idea to keep this export
than to require external users to open-code this piece of code instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-17 21:14:40 +01:00
Adrian Bunk
86b6c7a7f7 fs/block_dev.c: remove #if 0'ed code
Commit b2e895dbd8 #if 0'ed this code stating:

<--  snip  -->

    [PATCH] revert blockdev direct io back to 2.6.19 version

    Andrew Vasquez is reporting as-iosched oopses and a 65% throughput
    slowdown due to the recent special-casing of direct-io against
    blockdevs.  We don't know why either of these things are occurring.

    The patch minimally reverts us back to the 2.6.19 code for a 2.6.20
    release.

<--  snip  -->

It has since been dead code, and unless someone wants to revive it now
it's time to remove it.

This patch also makes bio_release_pages() static again and removes the
ki_bio_count member from struct kiocb, reverting changes that had been
done for this dead code.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
2008-02-19 10:04:00 +01:00
Jens Axboe
5d84070ee0 __bio_clone: don't calculate hw/phys segment counts
If the users sets a new ->bi_bdev on the bio after __bio_clone() has
returned it, the "segment counts valid" flag still remains even though
it may be different with the new target. So don't calculate segment
counts in __bio_clone().

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:04:46 +01:00
Jens Axboe
992c5ddaf1 bio: make freeing of ->bi_io_vec conditional in bio_free()
The empty barrier patches do not carry data, so they have no
iovec attached.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 11:03:52 +02:00
Jens Axboe
2b94de552e bio: use memset() in bio_init()
Use memset() to clear the bio, instead of doing each field manually.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 11:03:51 +02:00
NeilBrown
6712ecf8f6 Drop 'size' argument from bio_endio and bi_end_io
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>
2007-10-10 09:25:57 +02:00
NeilBrown
5bb23a688b Don't decrement bi_size in bio_endio
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>
2007-10-10 09:25:57 +02:00
NeilBrown
9cc54d40b8 Only call bi_end_io once for any bio
Currently bi_end_io can be called multiple times as sub-requests
complete.  However no ->bi_end_io function wants to know about that.
So only call when the bio is complete.

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

### Diffstat output
 ./fs/bio.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff .prev/fs/bio.c ./fs/bio.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:57 +02:00
Jens Axboe
165125e1e4 [BLOCK] Get rid of request_queue_t typedef
Some of the code has been gradually transitioned to using the proper
struct request_queue, but there's lots left. So do a full sweet of
the kernel and get rid of this typedef and replace its uses with
the proper type.

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

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

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-20 10:11:58 +09:00
Adrian Bunk
72d3a38ee0 unexport bio_{,un}map_user
bio_{,un}map_user no longer have any modular users.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-10 08:03:34 +02:00
Christoph Lameter
0a31bd5f2b KMEM_CACHE(): simplify slab cache creation
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>
2007-05-07 12:12:55 -07:00
Jens Axboe
5972511b77 [BLOCK] Don't pin lots of memory in mempools
Currently we scale the mempool sizes depending on memory installed
in the machine, except for the bio pool itself which sits at a fixed
256 entry pre-allocation.

There's really no point in "optimizing" this OOM path, we just need
enough preallocated to make progress. A single unit is enough, lets
scale it down to 2 just to be on the safe side.

This patch saves ~150kb of pinned kernel memory on a 32-bit box.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-04-30 09:08:17 +02:00