Commit Graph

175 Commits

Author SHA1 Message Date
Matias Bjorling 12f8f4fc03 null_blk: documentation
Add description of module and its parameters.

Signed-off-by: Matias Bjorling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-12-19 08:09:41 -07:00
Kent Overstreet 4550dd6c6b block: Immutable bio vecs
This adds a mechanism by which we can advance a bio by an arbitrary
number of bytes without modifying the biovec: bio->bi_iter.bi_bvec_done
indicates the number of bytes completed in the current bvec.

Various driver code still needs to be updated to not refer to the bvec
directly before we can use this for interesting things, like efficient
bio splitting.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: drbd-user@lists.linbit.com
Cc: nbd-general@lists.sourceforge.net
2013-11-23 22:33:49 -08:00
Kent Overstreet 4f024f3797 block: Abstract out bvec iterator
Immutable biovecs are going to require an explicit iterator. To
implement immutable bvecs, a later patch is going to add a bi_bvec_done
member to this struct; for now, this patch effectively just renames
things.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: Benny Halevy <bhalevy@tonian.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Ben Myers <bpm@sgi.com>
Cc: xfs@oss.sgi.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchand@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Peng Tao <tao.peng@emc.com>
Cc: Andy Adamson <andros@netapp.com>
Cc: fanchaoting <fanchaoting@cn.fujitsu.com>
Cc: Jie Liu <jeff.liu@oracle.com>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Pankaj Kumar <pankaj.km@samsung.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Mel Gorman <mgorman@suse.de>6
2013-11-23 22:33:47 -08:00
Paul Gortmaker 080506ad0a block: change config option name for cmdline partition parsing
Recently commit bab55417b1 ("block: support embedded device command
line partition") introduced CONFIG_CMDLINE_PARSER.  However, that name
is too generic and sounds like it enables/disables generic kernel boot
arg processing, when it really is block specific.

Before this option becomes a part of a full/final release, add the BLK_
prefix to it so that it is clear in absence of any other context that it
is block specific.

In addition, fix up the following less critical items:
 - help text was not really at all helpful.
 - index file for Documentation was not updated
 - add the new arg to Documentation/kernel-parameters.txt
 - clarify wording in source comments

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Cai Zhiyong <caizhiyong@huawei.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-30 14:31:02 -07:00
Cai Zhiyong bab55417b1 block: support embedded device command line partition
Read block device partition table from command line.  The partition used
for fixed block device (eMMC) embedded device.  It is no MBR, save
storage space.  Bootloader can be easily accessed by absolute address of
data on the block device.  Users can easily change the partition.

This code reference MTD partition, source "drivers/mtd/cmdlinepart.c"
About the partition verbose reference
"Documentation/block/cmdline-partition.txt"

[akpm@linux-foundation.org: fix printk text]
[yongjun_wei@trendmicro.com.cn: fix error return code in parse_parts()]
Signed-off-by: Cai Zhiyong <caizhiyong@huawei.com>
Cc: Karel Zak <kzak@redhat.com>
Cc: "Wanglin (Albert)" <albert.wanglin@huawei.com>
Cc: Marius Groeger <mag@sysgo.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Artem Bityutskiy <dedekind@infradead.org>
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:56:57 -07:00
Masanari Iida c9f3f2d8b3 doc: Fix typo in doucmentations
Correct typo (double words) in documentations.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-07-25 12:34:15 +02:00
Anatol Pomozov f884ab15af doc: fix misspellings with 'codespell' tool
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-28 12:02:12 +02:00
Namjae Jeon fdc6fdc52e Documentation: cfq-iosched: update documentation help for cfq tunables
Add the documentation text for latency, target_latency & group_idle
tunnable parameters in the block/cfq-iosched.txt.
Also fix few typo(spelling) mistakes.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>

Language somewhat modified by Jens.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-04-09 14:57:06 +02:00
Tejun Heo d02f7aa8dc cfq-iosched: enable full blkcg hierarchy support
With the previous two patches, all cfqg scheduling decisions are based
on vfraction and ready for hierarchy support.  The only thing which
keeps the behavior flat is cfqg_flat_parent() which makes vfraction
calculation consider all non-root cfqgs children of the root cfqg.

Replace it with cfqg_parent() which returns the real parent.  This
enables full blkcg hierarchy support for cfq-iosched.  For example,
consider the following hierarchy.

        root
      /      \
   A:500      B:250
  /     \
 AA:500  AB:1000

For simplicity, let's say all the leaf nodes have active tasks and are
on service tree.  For each leaf node, vfraction would be

 AA: (500  / 1500) * (500 / 750) =~ 0.2222
 AB: (1000 / 1500) * (500 / 750) =~ 0.4444
  B:                 (250 / 750) =~ 0.3333

and vdisktime will be distributed accordingly.  For more detail,
please refer to Documentation/block/cfq-iosched.txt.

v2: cfq-iosched.txt updated to describe group scheduling as suggested
    by Vivek.

v3: blkio-controller.txt updated.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2013-01-09 08:05:11 -08:00
Kent Overstreet 4254bba17d block: Kill bi_destructor
Now that we've got generic code for freeing bios allocated from bio
pools, this isn't needed anymore.

This patch also makes bio_free() static, since without bi_destructor
there should be no need for it to be called anywhere else.

bio_free() is now only called from bio_put, so we can refactor those a
bit - move some code from bio_put() to bio_free() and kill the redundant
bio->bi_next = NULL.

v5: Switch to BIO_KMALLOC_POOL ((void *)~0), per Boaz
v6: BIO_KMALLOC_POOL now NULL, drop bio_free's EXPORT_SYMBOL
v7: No #define BIO_KMALLOC_POOL anymore

Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-09-09 10:35:39 +02:00
Namjae Jeon 4004e90cfa Documentation: update tunable options in block/cfq-iosched.txt
Update tunable options in block/cfq-iosched.txt.

Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-08-09 15:28:05 +02:00
Namjae Jeon 2792d87193 Documentation: update tunable options in block/cfq-iosched.txt
Update tunable options in block/cfq-iosched.txt.

Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-08-09 15:27:29 +02:00
Namjae Jeon 865826644e Documentation: update missing index files in block/00-INDEX
Update missing index files in block/00-INDEX.

Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-08-09 15:27:28 +02:00
Tejun Heo a051661ca6 blkcg: implement per-blkg request allocation
Currently, request_queue has one request_list to allocate requests
from regardless of blkcg of the IO being issued.  When the unified
request pool is used up, cfq proportional IO limits become meaningless
- whoever grabs the next request being freed wins the race regardless
of the configured weights.

This can be easily demonstrated by creating a blkio cgroup w/ very low
weight, put a program which can issue a lot of random direct IOs there
and running a sequential IO from a different cgroup.  As soon as the
request pool is used up, the sequential IO bandwidth crashes.

This patch implements per-blkg request_list.  Each blkg has its own
request_list and any IO allocates its request from the matching blkg
making blkcgs completely isolated in terms of request allocation.

* Root blkcg uses the request_list embedded in each request_queue,
  which was renamed to @q->root_rl from @q->rq.  While making blkcg rl
  handling a bit harier, this enables avoiding most overhead for root
  blkcg.

* Queue fullness is properly per request_list but bdi isn't blkcg
  aware yet, so congestion state currently just follows the root
  blkcg.  As writeback isn't aware of blkcg yet, this works okay for
  async congestion but readahead may get the wrong signals.  It's
  better than blkcg completely collapsing with shared request_list but
  needs to be improved with future changes.

* After this change, each block cgroup gets a full request pool making
  resource consumption of each cgroup higher.  This makes allowing
  non-root users to create cgroups less desirable; however, note that
  allowing non-root users to directly manage cgroups is already
  severely broken regardless of this patch - each block cgroup
  consumes kernel memory and skews IO weight (IO weights are not
  hierarchical).

v2: queue-sysfs.txt updated and patch description udpated as suggested
    by Vivek.

v3: blk_get_rl() wasn't checking error return from
    blkg_lookup_create() and may cause oops on lookup failure.  Fix it
    by falling back to root_rl on blkg lookup failures.  This problem
    was spotted by Rakesh Iyer <rni@google.com>.

v4: Updated to accomodate 458f27a982 "block: Avoid missed wakeup in
    request waitqueue".  blk_drain_queue() now wakes up waiters on all
    blkg->rl on the target queue.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-06-26 18:42:49 -04:00
Wang Sheng-Hui b31966816d Documentation: drop as block elevator reference in switching-sched.txt
Remove 'as' for as is no longer supported, and we can not use
'elevator=as' any more.

Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-04 12:01:48 -07:00
Paul Bolle 395cf9691d doc: fix broken references
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-27 18:08:04 +02:00
Vivek Goyal 4931402a9d cfq-iosched: Add documentation about idling
There are always questions about why CFQ is idling on various conditions.
Recent ones is Christoph asking again why to idle on REQ_NOIDLE. His
assertion is that XFS is relying more and more on workqueues and is
concerned that CFQ idling on IO from every workqueue will impact
XFS badly.

So he suggested that I add some more documentation about CFQ idling
and that can provide more clarity on the topic and also gives an
opprotunity to poke a hole in theory and lead to improvements.

So here is my attempt at that. Any comments are welcome.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-08-05 09:42:20 +02:00
Dan Williams 5757a6d76c block: strict rq_affinity
Some systems benefit from completions always being steered to the strict
requester cpu rather than the looser "per-socket" steering that
blk_cpu_to_group() attempts by default. This is because the first
CPU in the group mask ends up being completely overloaded with work,
while the others (including the original submitter) has power left
to spare.

Allow the strict mode to be set by writing '2' to the sysfs control
file. This is identical to the scheme used for the nomerges file,
where '2' is a more aggressive setting than just being turned on.

echo 2 > /sys/block/<bdev>/queue/rq_affinity

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Roland Dreier <roland@purestorage.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-07-23 20:44:25 +02:00
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
Jens Axboe 7eaceaccab block: remove per-queue plugging
Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10 08:52:07 +01:00
Randy Dunlap 17a9e7bbae Documentation: remove anticipatory scheduler info
Remove anticipatory block I/O scheduler info from Documentation/
since the code has been deleted.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Reported-by: "Robert P. J. Day" <rpjday@crashcourse.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-11 12:09:59 +01:00
Jens Axboe fa251f8990 Merge branch 'v2.6.36-rc8' into for-2.6.37/barrier
Conflicts:
	block/blk-core.c
	drivers/block/loop.c
	mm/swapfile.c

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-19 09:13:04 +02:00
Christoph Hellwig 04ccc65cd1 block: update documentation for REQ_FLUSH / REQ_FUA
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-10 12:35:37 +02:00
Vivek Goyal 6d6ac1c1a3 cfq-iosched: Documentation help for new tunables
Some documentation to provide help with tunables.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-23 12:25:29 +02:00
Nick Piggin 6e57559022 nick piggin: change email address
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-05 08:45:20 -07:00
FUJITA Tomonori c2282adbde Documentation: fix block/biodoc.txt dma mapping description
- It looks incorrect to use blk_rq_map_sg with pci_map_page here about
  DMA mappings. dma_map_sg?

- better to use dma_map_page instead of pci_map_page.
  http://marc.info/?l=linux-kernel&m=126596737604808&w=2

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-03-08 09:11:07 +01:00
Jens Axboe f11cbd74c5 Merge branch 'master' into for-2.6.34 2010-02-22 13:48:51 +01:00
Alan D. Brunelle 488991e28e block: Added in stricter no merge semantics for block I/O
Updated 'nomerges' tunable to accept a value of '2' - indicating that _no_
merges at all are to be attempted (not even the simple one-hit cache).

The following table illustrates the additional benefit - 5 minute runs of
a random I/O load were applied to a dozen devices on a 16-way x86_64 system.

nomerges        Throughput      %System         Improvement (tput / %sys)
--------        ------------    -----------     -------------------------
0               12.45 MB/sec    0.669365609
1               12.50 MB/sec    0.641519199     0.40% / 2.71%
2               12.52 MB/sec    0.639849750     0.56% / 2.96%

Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-01-29 09:04:08 +01:00
Kusanagi Kouichi 4207a152bc Documentation: Rename Documentation/DMA-mapping.txt
It seems that Documentation/DMA-mapping.txt was supposed to be renamed
to Documentation/PCI/PCI-DMA-mapping.txt.

Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-02 10:09:44 -08:00
FUJITA Tomonori 1de6129f38 block: remove Documentation/block/as-iosched.txt
Commit 492af6350a removed
the AS IO scheduler, so remove its documentation too.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-12-18 12:37:48 +01:00
Andre Noll 61fd21670d Trivial typo fixes in Documentation/block/data-integrity.txt.
Signed-off-by: Andre Noll <maan@systemlinux.org>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-07-01 10:56:25 +02:00
Matt LaPlante 19f5946001 trivial: Miscellaneous documentation typo fixes
Fix various typos in documentation txts.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-06-12 18:01:47 +02:00
vibi sreenivasan dbdc9dd342 Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt
File Documentation/PCI/PCI-DMA-mapping.txt does not exist.
 Documentation/DMA-mapping.txt contains DMA Mapping details

Signed-off-by: vibi sreenivasan <vibi_sreenivasan@cms.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-06-02 14:52:32 +02:00
Jens Axboe 329007ce25 block: update biodoc.txt on plugging
We do per-device plugging, get rid of any references to tq_disk as that
has been dead since 2.6.5 or so.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 08:28:11 +02:00
Avishay Traeger 07e86f405a block: Repeated lines in switching-sched.txt
These lines appear in this file twice - removed one occurrence.

Signed-off-by: Avishay Traeger <avishay@il.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-26 11:01:28 +01:00
Jens Axboe cbb5901b90 block: add text file detailing queue/ sysfs files
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-02-02 13:02:31 +01:00
Nikanth Karthikesan 7598909e3e Mark mandatory elevator functions in the biodoc.txt
biodoc.txt mentions that elevator functions marked with * are mandatory, but
no function is marked with *. Mark the 3 functions which should be
implemented by any io scheduler.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-01-30 12:34:37 +01:00
Randy Dunlap 5872fb94f8 Documentation: move DMA-mapping.txt to Doc/PCI/
Move DMA-mapping.txt to Documentation/PCI/.

DMA-mapping.txt was supposed to be moved from Documentation/ to
Documentation/PCI/.  The 00-INDEX files in those two directories
were updated, along with a few other text files, but the file
itself somehow escaped being moved, so move it and update more
text files and source files with its new location.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
cc:	Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-29 18:19:29 -08:00
Nikanth Karthikesan 4236469099 Documentation: remove reference to ll_rw_blk.c and moved drivers/block/elevator.c
The drivers/block/ll_rw_block.c has been split and organized in the block/
directory, and also drivers/block/elevator.c has been moved to the block/
directory. Update Documentation/block/biodoc.txt accordingly

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:43 +01:00
Linus Torvalds d1b5726358 Merge branch 'docs' of git://git.lwn.net/linux-2.6
* 'docs' of git://git.lwn.net/linux-2.6:
  Document panic_on_unrecovered_nmi sysctl
  Add a reference to paper to SubmittingPatches
  Add kerneldoc documentation for new printk format extensions
  Remove videobook.tmpl
  doc: Test-by?
  Add the development process document
  Documentation/block/data-integrity.txt: Fix section numbers
2008-10-16 12:18:16 -07:00
Alberto Bertogli d86f4bc4bc Documentation/block/data-integrity.txt: Fix section numbers
Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-10-16 11:51:30 -06:00
Aaron Carroll 6a421c1dc9 block: update documentation for deadline fifo_batch tunable
Update the description of fifo_batch to match the current implementation,
and include a description of how to tune it.

Signed-off-by: Aaron Carroll <aaronc@gelato.unsw.edu.au>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:03 +02:00
Martin K. Petersen c1c72b5994 block: Data integrity infrastructure documentation
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
Robert P. J. Day c0d1f29534 DOCUMENTATION: Use newer DEFINE_SPINLOCK macro in docs.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
2008-04-21 22:44:50 +00:00
Rob Landley 8b6800fbce Add Documentation/block/00-INDEX
Add Documentation/block/00-INDEX

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 10:11:28 +02:00
Alan D. Brunelle 23c76983e2 Some IO scheduler cleanup in Documentation/block
as-iosched.txt:
  o  Changed IO scheduler selection text to a reference to the
     switching-sched.txt file.

  o  Fixed typo: 'for up time...' -> 'for up to...'

  o  Added short description of the est_time file.

deadline-iosched.txt:
  o  Changed IO scheduler selection text to a reference to the
     switching-sched.txt file.

  o  Removed references to non-existent seek-cost and stream_unit.

  o  Fixed typo: 'write_starved' -> 'writes_starved'

switching-sched.txt:
  o  Added in boot-time argument to set the default IO scheduler. (From
     as-iosched.txt)

  o  Added in sysfs mount instructions. (From deadline-iosched.txt)

Signed-off-by: Alan D. Brunelle <Alan.Brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 09:59:55 +02:00
Rob Landley 26bbb29a2a Update Jens Axboe's email in Documentation/*
Jens Axboe's old email address bounces.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 09:59:55 +02:00
Dhaval Giani 3317fedba9 Corrections in Documentation/block/ioprio.txt
The newer glibc does not allow system calls to be made via _syscallN()
wrapper. They have to be made through syscall(). The ionice code used
the older interface. Correcting it to use syscall.

Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:57 +02:00
NeilBrown 5705f70217 Introduce rq_for_each_segment replacing rq_for_each_bio
Every usage of rq_for_each_bio wraps a usage of
bio_for_each_segment, so these can be combined into
rq_for_each_segment.

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

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

Various compile fixes by me...

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:56 +02:00
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
Geert Uytterhoeven c0613c1c94 Documentation/block/barrier.txt is not in sync with the actual code: - blk_queue_ordered() no longer has a gfp_mask parameter - blk_queue_ordered_locked() no longer exists - sd_prepare_flush() looks slightly different
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-10 13:43:34 +02:00
Kristen Carlson Accardi 86ce18d7b7 genhd: expose AN to user space
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>
2007-05-23 20:14:11 -07:00
Matt LaPlante a982ac06b0 misc doc and kconfig typos
Fix various typos in kernel docs and Kconfigs, 2.6.21-rc4.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-05-09 08:58:15 +02:00
Jens Axboe 126ec9a676 [PATCH] block: document io scheduler allow_merge_fn hook
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2006-12-20 11:06:15 +01:00
Filipe 49033c8184 [PATCH] io/storage: Documentation update to as-iosched.txt
Documentation update, adding references to CFQ scheduler and to another
document about selecting IO Schedulers.

Signed-off-by: Filipe Lautert <filipe@icewall.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:32 -08:00
Matt LaPlante 5d3f083d8f Fix typos in /Documentation : Misc
This patch fixes typos in various Documentation txts. The patch addresses some
misc words.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-30 05:21:10 +01:00
Matt LaPlante 4ae0edc21b Fix typos in /Documentation : 'U-Z'
This patch fixes typos in various Documentation txts. The patch addresses some
+words starting with the letters 'U-Z'.

Looks like I made it through the alphabet...just in time to start over again
+too!  Maybe I can fit more profound fixes into the next round...?  Time will
+tell. :)

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-30 04:58:40 +01:00
Paolo Ornati 670e9f34ee Documentation: remove duplicated words
Remove many duplicated words under Documentation/ and do other small
cleanups.

Examples:
        "and and" --> "and"
        "in in" --> "in"
        "the the" --> "the"
        "the the" --> "to the"
        ...

Signed-off-by: Paolo Ornati <ornati@fastwebnet.it>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:57:56 +02:00
Matt LaPlante 53cb47268e Fix typos in Documentation/: 'S'
This patch fixes typos in various Documentation txts. The patch addresses
some words starting with the letter 'S'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Alan Cox <alan@redhat.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:55:17 +02:00
Matt LaPlante d6bc8ac9e1 Fix typos in Documentation/: 'Q'-'R'
This patch fixes typos in various Documentation txts. The patch addresses
some words starting with the letters 'Q'-'R'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:54:15 +02:00
Matt LaPlante 992caacf11 Fix typos in Documentation/: 'N'-'P'
This patch fixes typos in various Documentation txts. The patch addresses
some words starting with the letters 'N'-'P'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:52:05 +02:00
Matt LaPlante 2fe0ae78c6 Fix typos in Documentation/: 'H'-'M'
This patch fixes typos in various Documentation txts. The patch addresses
some words starting with the letters 'H'-'M'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:50:39 +02:00
Matt LaPlante a2ffd27516 Fix typos in Documentation/: 'F'-'G'
This patch fixes typos in various Documentation txts. The patch addresses
some words starting with the letters 'F'-'G'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:49:15 +02:00
Matt LaPlante fff9289b21 Fix typos in Documentation/: 'D'-'E'
This patch fixes typos in various Documentation txts. This patch addresses
some words starting with the letters 'D'-'E'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:47:42 +02:00
Matt LaPlante 6c28f2c0f2 Fix typos in Documentation/: 'B'-'C'
This patch fixes typos in various Documentation txts. This patch addresses some
words starting with the letters 'B'-'C'.  There are also a few grammar fixes
thrown in for Randy. ;)

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:46:31 +02:00
Valdis Kletnieks 73af994c7d [PATCH] Document online io scheduler switching
We added the ability to change a block device's IO elevator scheduler both
at kernel boot and on-the-fly, but we only documented the elevator= boot
parameter.  Add a quick how-to on doing it on the fly.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-20 13:04:36 +02:00
Mike Christie 28832e8337 [PATCH] update max_sectors documentation
The max_sectors has been split into max_hw_sectors and max_sectors for some
time. A patch to have blk_queue_max_sectors enforce this was sent by
me and it broke IDE. This patch updates the documentation.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-27 09:29:01 +02:00
Tejun Heo 5a22579137 barrier.txt got lost while the new barrier patchset was climbing up
the ladder to the mainline.  Add it back.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-01-16 09:45:58 +01:00
Andy Isaacson 37a327957e [PATCH] block/stat.txt
I couldn't find any docs explaining the contents of /sys/block/<dev>/stat,
so I wrote up the following.  I'm not completely sure it's accurate - Jens,
could you give a yea or nay on this?

In particular, the counts of read/write IOs and read/write sectors are
incremented in different places - it looks like they both increment as the
request is being finished, but I'm not completely sure of that.

Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:01 -08:00
Tejun Heo ff5b8cf149 [BLOCK] I/O barrier documentation update
Update documentation to match new barrier implementation.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-01-06 09:58:37 +01:00
Adrian Bunk f4b09ebc8b update the email address of Randy Dunlap
This patch removes all references to the bouncing address
rddunlap@osdl.org and one dead web page from the kernel.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
2006-01-03 13:37:51 +01:00
Ben Collins 1d193f4f11 [PATCH] Update location of ll_rw_blk.c in docs
Picked from the ubuntu-2.6 tree

The change in location for ll_rw_blk.c from drivers/block/ to block/ caused
failure to generate documentation.

Signed-off-by: Ben Collins <bcollins@ubuntu.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-15 08:59:20 -08:00
Tejun Heo 4c9f783640 [PATCH] 05/05 update biodoc to match new generic dispatch api
Updates biodoc to reflect changes in elevator API

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2005-10-28 08:45:47 +02:00
Jens Axboe 52a5e15f66 [PATCH] CFQ io scheduler, add ioprio documentation
Add ioprio documentation

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-27 14:33:30 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00