Commit Graph

799 Commits

Author SHA1 Message Date
Tejun Heo
870d665612 block: implement CONFIG_DEBUG_BLOCK_EXT_DEVT
Extended devt introduces non-contiguos device numbers.  This patch
implements a debug option which forces most devt allocations to be
from the extended area and spreads them out.  This is enabled by
default if DEBUG_KERNEL is set and achieves...

1. Detects code paths in kernel or userland which expect predetermined
   consecutive device numbers.

2. When something goes wrong, avoid corruption as adding to the minor
   of earlier partition won't lead to the wrong but valid device.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:06 +02:00
Tejun Heo
1f0142905d block: adjust formatting for large minors and add ext_range sysfs attr
With extended minors and the soon-to-follow debug feature, large minor
numbers for block devices will be common.  This patch does the
followings to make printouts pretty.

* Adapt print formats such that large minors don't break the
  formatting.

* For extended MAJ:MIN, %02x%02x for MAJ:MIN used in
  printk_all_partitions() doesn't cut it anymore.  Update it such that
  %03x:%05x is used if either MAJ or MIN doesn't fit in %02x.

* Implement ext_range sysfs attribute which shows total minors the
  device can use including both conventional minor space and the
  extended one.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:06 +02:00
Tejun Heo
bcce3de1be block: implement extended dev numbers
Implement extended device numbers.  A block driver can tell block
layer that it wants to use extended device numbers.  After the usual
minor space is used up, block layer automatically allocates devt's
from EXT_BLOCK_MAJOR.

Currently only one major number is allocated for this but as the
allocation is strictly on-demand, ~1mil minor space under it should
suffice unless the system actually has more than ~1mil partitions and
if that ever happens adding more majors to the extended devt area is
easy.

Due to internal implementation issues, the first partition can't be
allocated on the extended area.  In other words, genhd->minors should
at least be 1.  This limitation will be lifted by later changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:06 +02:00
Tejun Heo
c995905916 block: fix diskstats access
There are two variants of stat functions - ones prefixed with double
underbars which don't care about preemption and ones without which
disable preemption before manipulating per-cpu counters.  It's unclear
whether the underbarred ones assume that preemtion is disabled on
entry as some callers don't do that.

This patch unifies diskstats access by implementing disk_stat_lock()
and disk_stat_unlock() which take care of both RCU (for partition
access) and preemption (for per-cpu counter access).  diskstats access
should always be enclosed between the two functions.  As such, there's
no need for the versions which disables preemption.  They're removed
and double underbars ones are renamed to drop the underbars.  As an
extra argument is added, there's no danger of using the old version
unconverted.

disk_stat_lock() uses get_cpu() and returns the cpu index and all
diskstat functions which access per-cpu counters now has @cpu
argument to help RT.

This change adds RCU or preemption operations at some places but also
collapses several preemption ops into one at others.  Overall, the
performance difference should be negligible as all involved ops are
very lightweight per-cpu ones.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:06 +02:00
Tejun Heo
e71bf0d0ee block: fix disk->part[] dereferencing race
disk->part[] is protected by its matching bdev's lock.  However,
non-critical accesses like collecting stats and printing out sysfs and
proc information used to be performed without any locking.  As
partitions can come and go dynamically, partitions can go away
underneath those non-critical accesses.  As some of those accesses are
writes, this theoretically can lead to silent corruption.

This patch fixes the race by using RCU for the partition array and dev
reference counter to hold partitions.

* Rename disk->part[] to disk->__part[] to make sure no one outside
  genhd layer proper accesses it directly.

* Use RCU for disk->__part[] dereferencing.

* Implement disk_{get|put}_part() which can be used to get and put
  partitions from gendisk respectively.

* Iterators are implemented to help iterate through all partitions
  safely.

* Functions which require RCU readlock are marked with _rcu suffix.

* Use disk_put_part() in __blkdev_put() instead of directly putting
  the contained kobject.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:06 +02:00
Tejun Heo
f331c0296f block: don't depend on consecutive minor space
* Implement disk_devt() and part_devt() and use them to directly
  access devt instead of computing it from ->major and ->first_minor.

  Note that all references to ->major and ->first_minor outside of
  block layer is used to determine devt of the disk (the part0) and as
  ->major and ->first_minor will continue to represent devt for the
  disk, converting these users aren't strictly necessary.  However,
  convert them for consistency.

* Implement disk_max_parts() to avoid directly deferencing
  genhd->minors.

* Update bdget_disk() such that it doesn't assume consecutive minor
  space.

* Move devt computation from register_disk() to add_disk() and make it
  the only one (all other usages use the initially determined value).

These changes clean up the code and will help disk->part dereference
fix and extended block device numbers.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:05 +02:00
Tejun Heo
cf771cb5a7 block: make variable and argument names more consistent
In hd_struct, @partno is used to denote partition number and a number
of other places use @part to denote hd_struct.  Functions use @part
and @index instead.  This causes confusion and makes it difficult to
use consistent variable names for hd_struct.  Always use @partno if a
variable represents partition number.

Also, print out functions use @f or @part for seq_file argument.  Use
@seqf uniformly instead.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:05 +02:00
Tejun Heo
310a2c1012 block: misc updates
This patch makes the following misc updates in preparation for
disk->part dereference fix and extended block devt support.

* implment part_to_disk()

* fix comment about gendisk->part indexing

* rename get_part() to disk_map_sector()

* don't use n which is always zero while printing disk information in
  diskstats_show()

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:04 +02:00
Tejun Heo
88e341261c block: update add_partition() error handling
d805dda4 tried to fix error case handling in add_partition() but had a
few problems.

* disk->part[] entry is set early and left dangling if operation
  fails.

* Once device initialized, the last put_device() is responsible for
  freeing all the resources.  The failure path freed part_stats and p
  regardless of put_device() causing double free.

* holders subdir holds reference to the disk device, so failure path
  should remove it to release resources properly which was missing.

This patch fixes the above problems and while at it move partition
slot busy check into add_partition() for completeness and inlines
holders subdirectory creation.  Using separate function for it just
obfuscates the code.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Abdel Benamrouche <draconux@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:04 +02:00
Tejun Heo
ec2cdedf79 block: allow deleting zero length partition
delete_partition() was noop for zero length partition.  As the
addition code allows creating zero lenght partition and deletion is
assumed to always succeed, this causes memory leak for zero length
partitions.  Allow zero length partitions to end their meaningless
lives.

While at it, allow deleting zero lenght partition via
BLKPG_DEL_PARTITION ioctl too.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:04 +02:00
Tejun Heo
def4e38ddd block: use class_dev_iterator instead of class_for_each_device()
Recent block_class iteration updates 5c6f35c5..27f3025 converted all
class device iteration to class_for_each_device() and
class_find_device(), which are correct but pain in the ass to use.
This pach converts them to newly introduced class_dev_iterator so that
they can use more natural control structures instead of separate
callbacks and struct to pass parameters to them.

This results in smaller and easier code.

This patch also restores the original behavior of not printing header
in /proc/partitions if there's no partition to print.  This is trivial
but still user-visible behavior.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:04 +02:00
Tejun Heo
2ac3cee529 block: don't grab block_class_lock unnecessarily
block_class_lock protects major_names array and bdev_map and doesn't
have anything to do with block class devices.  Don't grab them while
iterating over block class devices.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:04 +02:00
Tejun Heo
ac65ece4ee block: fix partition info printouts
Recent block_class iteration updates 5c6f35c5..27f3025 broke partition
info printouts.

* printk_all_partitions(): Partition print out stops when it meets a
  partition hole.  Partition printing inner loop should continue
  instead of exiting on empty partition slot.

* /proc/partitions and /proc/diskstats: If all information can't be
  read in single read(), the information is truncated.  This is
  because find_start() doesn't actually update the counter containing
  the initial seek.  It runs to the end and ends up always reporting
  EOF on the second read.

This patch fixes both problems.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:04 +02:00
Randy Dunlap
710027a48e Add some block/ source files to the kernel-api docbook. Fix kernel-doc notation in them as needed. Fix changed function parameter names. Fix typos/spellos. In comments, change REQ_SPECIAL to REQ_TYPE_SPECIAL and REQ_BLOCK_PC to REQ_TYPE_BLOCK_PC.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:03 +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
Aaron Carroll
4fb72f7646 deadline-iosched: non-functional fixes
* convert goto to simpler while loop;
 * use rq_end_sector() instead of computing manually;
 * fix false comments;
 * remove spurious whitespace;
 * convert rq_rb_root macro to an inline function.

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
Aaron Carroll
63de428b13 deadline-iosched: allow non-sequential batching
Deadline currently only batches sector-contiguous requests, so except
for a few circumstances (e.g. requests in a single direction), it is
essentially first come first served.  This is bad for throughput, so
change it to CSCAN, which means requests in a batch do not need to be
sequential and are issued in increasing sector order.

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

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

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:02 +02:00
David Woodhouse
d30a2605be Add BLKDISCARD ioctl to allow userspace to discard sectors
We may well want mkfs tools to use this to mark the whole device as
unwanted before they format it, for example.

The ioctl takes a pair of uint64_ts, which are start offset and length
in _bytes_. Although at the moment it might make sense for them both to
be in 512-byte sectors, I don't want to limit the ABI to that.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:02 +02:00
OGAWA Hirofumi
2ebca85abc Use WRITE_BARRIER in blkdev_issue_flush(), not (1<<BIO_RW_BARRIER)
Barriers should be submitted with the WRITE flag set.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:02 +02:00
David Woodhouse
35ba8f7083 blktrace: simplify flags handling in __blk_add_trace
Let the compiler see what's going on, and it can all get a lot simpler.
On PPC64 this reduces the size of the code calculating these bits by
about 60%. On x86_64 it's less of a win -- only 40%.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:01 +02:00
David Woodhouse
27b29e86bf blktrace: support discard requests
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:01 +02:00
David Woodhouse
fb2dce862d Add 'discard' request handling
Some block devices benefit from a hint that they can forget the contents
of certain sectors. Add basic support for this to the block core, along
with a 'blkdev_issue_discard()' helper function which issues such
requests.

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

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

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:01 +02:00
David Woodhouse
d628eaef31 Fix up comments about matching flags between bio and rq
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:01 +02:00
Jens Axboe
051cc3952a block: use bio_has_data() in the IO completion path
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:00 +02:00
Jens Axboe
a9c701e594 block: use bio_has_data() to check for data carrying bio
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:00 +02:00
xiphmont@xiph.org
35e396cd10 SG_IO block filter whitelist missing MMC SET READ AHEAD command
I have another request for the block filter SG_IO command whitelist,
specifically the MMC streaming command set SET READ AHEAD command.
The command applies only to MMC CDROM/DVDROM drives with the streaming
optional feature set.  The command is useful to cdparanoia in that it
allows explicit cache control side effects that are, on many drives,
cdparanoia's most efficient way to flush/disable the media cache on
cdrom drives. I am aware of no reason why it should not be accessible
from usespace.

Also note that the command is already fully accessible through the
SCSI-native version of the SG_IO ioctl as well as the traditional SG
interface.  The command is only being refused on block devices.  That
means that on a typical stock distro, the command is available through
/dev/sg* but not /dev/scd* although both are typically available and
accessible.  Filtering the command is not providing any protection,
only a confusing inconsistency.

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

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-09-11 14:20:23 +02:00
Tejun Heo
ddef43a843 block: restore original behavior of /proc/partition when there's no partition
/proc/partitions didn't use to write out the header if there was no
partition.  However, recent commit 66c64afe changed the behavior.
This is nothing major but there's no reason to change user visible
behavior without a good rationale.  Restore the original behavior.

Note that 2.6.28 has clean up changes scheduled which will replace
this rather hacky implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-09-01 08:55:10 +02:00
FUJITA Tomonori
bb23b431db remove blk_register_filter and blk_unregister_filter in gendisk
This patch remove blk_register_filter and blk_unregister_filter in
gendisk, and adds them to sd.c, sr.c. and ide-cd.c

The commit abf5439370 moved cmdfilter
from gendisk to request_queue. It turned out that in some subsystems
multiple gendisks share a single request_queue. So we get:

Using physmap partition information
Creating 3 MTD partitions on "physmap-flash":
0x00000000-0x01c00000 : "User FS"
0x01c00000-0x01c40000 : "booter"
kobject (8511c410): tried to init an initialized object, something is seriously wrong.
Call Trace:
[<8036644c>] dump_stack+0x8/0x34
[<8021f050>] kobject_init+0x50/0xcc
[<8021fa18>] kobject_init_and_add+0x24/0x58
[<8021d20c>] blk_register_filter+0x4c/0x64
[<8021c194>] add_disk+0x78/0xe0
[<8027d14c>] add_mtd_blktrans_dev+0x254/0x278
[<8027c8f0>] blktrans_notify_add+0x40/0x78
[<80279c00>] add_mtd_device+0xd0/0x150
[<8027b090>] add_mtd_partitions+0x568/0x5d8
[<80285458>] physmap_flash_probe+0x2ac/0x334
[<802644f8>] driver_probe_device+0x12c/0x244
[<8026465c>] __driver_attach+0x4c/0x84
[<80263c64>] bus_for_each_dev+0x58/0xac
[<802633ec>] bus_add_driver+0xc4/0x24c
[<802648e0>] driver_register+0xcc/0x184
[<80100460>] _stext+0x60/0x1bc

In the long term, we need to fix such subsystems but we need a quick
fix now. This patch add the command filter support to only sd and sr
though it might be useful for other SG_IO users (such as cciss).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reported-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-29 11:47:07 +02:00
Matthew Wilcox
0e3eb45e4f block: remove unused ->busy part of the block queue tag map
It's not used for anything. On top of that, it's racy and can thus
trigger a faulty BUG_ON() in __blk_free_tags() on queue exit.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-27 09:50:19 +02:00
Adel Gadllah
a4a778971b block: clean up cmdfilter sysfs interface
This patch changes the interface of the cmd filter to use a +/-
notation like:

echo -- +0x02 +0x03 -0x08

If neither + or - is given it defaults to + (allow command).

Note: The interface was added in 2.6.17-rc1 and is unused and
undocumented so far so it's safe to change it.

Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Reviewed-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: jens.axboe@oracle.com
Cc: James.Bottomley@hansenpartnership.com
Cc: dan.j.williams@intel.com
Cc: pjones@redhat.com
Cc: viro@zeniv.linux.org.uk
Cc: dougg@torque.net
Signed-off-by: Adel Gadllah <adel.gadllah@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-27 09:50:19 +02:00
FUJITA Tomonori
4beab5c623 block: rename blk_scsi_cmd_filter to blk_cmd_filter
Technically, the cmd_filter would be applied to other protocols though
it's unlikely to happen. Putting SCSI stuff to request_queue is kinda
layer violation. So let's rename it.

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

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

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

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

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

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-27 09:50:19 +02:00
Kay Sievers
5c0ef6d021 block: drop references taken by class_find_device()
Otherwise we leak references, which is not a good thing to do.


Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21 10:15:38 -07:00
Kay Sievers
068281d302 block: fix partial read() of /proc/{partitions,diskstats}
The proc files get truncated if they do not fit into the buffer with
a single read(). We need to move the seq_file index from the callback
of class_find_device() to the caller of class_find_device(), to keep
its value across multiple invocations of the callback.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21 10:15:38 -07:00
Linus Torvalds
f1b134fdf6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] scsi_transport_spi: fix oops in revalidate
  [SCSI] ses: fix VPD inquiry overrun
  [SCSI] block: Fix miscalculation of sg_io timeout in CDROM_SEND_PACKET handler.
  [SCSI] hptiop: add more PCI device IDs
2008-08-04 17:19:18 -07:00
Jens Axboe
6c5e0c4d51 block: add a blk_plug_device_unlocked() that grabs the queue lock
blk_plug_device() must be called with the queue lock held, so callers
often just grab and release the lock for that purpose. Add a helper
that does just that.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-01 20:31:32 +02:00
Tim Wright
ad337591f4 [SCSI] block: Fix miscalculation of sg_io timeout in CDROM_SEND_PACKET handler.
It seems cdrwtool in the udftools has been unusable on "modern" kernels
for some time. A Google search reveals many people with the same issue
but no solution (cdrwtool fails to format the disk). After spending some
time tracking down the issue, it comes down to the following:

The udftools still use the older CDROM_SEND_PACKET interface to send
things like FORMAT_UNIT through to the drive. They should really be
updated, but that's another story. Since most distros are using libata
now, the cd or dvd burner appears as a SCSI device, and we wind up in
block/scsi_ioctl.c. Here, the code tries to take the "struct
cdrom_generic_command" and translate it and stuff it into a "struct
sg_io_hdr" structure so it can pass it to the modern sg_io() routine
instead. Unfortunately, there is one error, or rather an omission in the
translation. The timeout that is passed in in the "struct
cdrom_generic_command" is in HZ=100 units, and this is modified and
correctly converted to jiffies by use of clock_t_to_jiffies(). However,
a little further down, this cgc.timeout value in jiffies is simply
copied into the sg_io_hdr timeout, which should be in milliseconds.
Since most modern x86 kernels seems to be getting build with HZ=250, the
timeout that is passed to sg_io and eventually converted to the
timeout_per_command member of the scsi_cmnd structure is now four times
too small. Since cdrwtool tries to set the timeout to one hour for the
FORMAT_UNIT command, and it takes about 20 minutes to format a 4x CDRW,
the SCSI error-handler kicks in after the FORMAT_UNIT completes because
it took longer than the incorrectly-calculated timeout.

[jejb: fix up whitespace]
Signed-off-by: Tim Wright <timw@splhi.com>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-30 10:18:29 -05:00
Arjan van de Ven
12e0036818 Use WARN() in block/
Use WARN() instead of a printk+WARN_ON() pair; this way the message
becomes part of the warning section for better reporting/collection.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:07 -07:00
FUJITA Tomonori
a76eef9573 block/blk-map.c: use the new object_is_on_stack() helper
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:02 -07:00
Abdel Benamrouche
04ebd4aee5 block/ioctl.c and fs/partition/check.c: check value returned by add_partition()
Now that add_partition() has been aught to propagate errors, let's check them.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Abdel Benamrouche <draconux@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:44 -07:00
Greg Kroah-Hartman
27f3025191 block: make /proc/partitions and /proc/diskstats use class_find_device()
Use the proper class iterator function instead of mucking around in the
internals of the class structures.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:49 -07:00
Greg Kroah-Hartman
66c64afec1 block: move header for /proc/partitions to seq_start
The seq_start call is the better place for the header for the file, that
way we don't have to be mucking in the class structure to try to figure
out if this is the first partition or not.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:49 -07:00
Greg Kroah-Hartman
68c4d4a787 block: make proc files seq_start use the class_find_device()
Use the proper class iterator function instead of mucking around in the
internals of the class structures.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:49 -07:00
Randy Dunlap
a6e2ba8877 block: make /proc/diskstats only build if CONFIG_PROC_FS is enabled
These functions are only needed if CONFIG_PROC_FS is enabled, so save
the space when it is not.

This also makes it easier for a patch later in this series to work
properly if CONFIG_PROC_FS is not enabled.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:49 -07:00
Greg Kroah-Hartman
a142be856f block: make blk_lookup_devt use the class iterator function
Use the proper class iterator function instead of mucking around in the
internals of the class structures.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:48 -07:00
Greg Kroah-Hartman
5c6f35c5ec block: make printk_partition use the class iterator function
Use the proper class iterator function instead of mucking around in the
internals of the class structures.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:48 -07:00
Greg Kroah-Hartman
6ffeea77ff block: fix compiler warning in genhd.c
Warn if something really bad happens if we can't create this link.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:48 -07:00
Greg Kroah-Hartman
f79f060561 device create: block: convert device_create to device_create_drvdata
device_create() is race-prone, so use the race-free
device_create_drvdata() instead as device_create() is going away.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:41 -07:00
Dan Williams
e105b8bfc7 sysfs: add /sys/dev/{char,block} to lookup sysfs path by major:minor
Why?:
There are occasions where userspace would like to access sysfs
attributes for a device but it may not know how sysfs has named the
device or the path.  For example what is the sysfs path for
/dev/disk/by-id/ata-ST3160827AS_5MT004CK?  With this change a call to
stat(2) returns the major:minor then userspace can see that
/sys/dev/block/8:32 links to /sys/block/sdc.

What are the alternatives?:
1/ Add an ioctl to return the path: Doable, but sysfs is meant to reduce
   the need to proliferate ioctl interfaces into the kernel, so this
   seems counter productive.

2/ Use udev to create these symlinks: Also doable, but it adds a
   udev dependency to utilities that might be running in a limited
   environment like an initramfs.

3/ Do a full-tree search of sysfs.

[kay.sievers@vrfy.org: fix duplicate registrations]
[kay.sievers@vrfy.org: cleanup suggestions]

Cc: Neil Brown <neilb@suse.de>
Cc: Tejun Heo <htejun@gmail.com>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Reviewed-by: SL Baur <steve@xemacs.org>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Mark Lord <lkml@rtr.ca>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:40 -07:00
Linus Torvalds
89a93f2f48 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (102 commits)
  [SCSI] scsi_dh: fix kconfig related build errors
  [SCSI] sym53c8xx: Fix bogus sym_que_entry re-implementation of container_of
  [SCSI] scsi_cmnd.h: remove double inclusion of linux/blkdev.h
  [SCSI] make struct scsi_{host,target}_type static
  [SCSI] fix locking in host use of blk_plug_device()
  [SCSI] zfcp: Cleanup external header file
  [SCSI] zfcp: Cleanup code in zfcp_erp.c
  [SCSI] zfcp: zfcp_fsf cleanup.
  [SCSI] zfcp: consolidate sysfs things into one file.
  [SCSI] zfcp: Cleanup of code in zfcp_aux.c
  [SCSI] zfcp: Cleanup of code in zfcp_scsi.c
  [SCSI] zfcp: Move status accessors from zfcp to SCSI include file.
  [SCSI] zfcp: Small QDIO cleanups
  [SCSI] zfcp: Adapter reopen for large number of unsolicited status
  [SCSI] zfcp: Fix error checking for ELS ADISC requests
  [SCSI] zfcp: wait until adapter is finished with ERP during auto-port
  [SCSI] ibmvfc: IBM Power Virtual Fibre Channel Adapter Client Driver
  [SCSI] sg: Add target reset support
  [SCSI] lib: Add support for the T10 (SCSI) Data Integrity Field CRC
  [SCSI] sd: Move scsi_disk() accessor function to sd.h
  ...
2008-07-15 18:58:04 -07:00
Linus Torvalds
98339cbd36 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6: (80 commits)
  ide-floppy: fix unfortunate function naming
  ide-tape: unify idetape_create_read/write_cmd
  ide: add ide_pc_intr() helper
  ide-{floppy,scsi}: read Status Register before stopping DMA engine
  ide-scsi: add more debugging to idescsi_pc_intr()
  ide-scsi: use pc->callback
  ide-floppy: add more debugging to idefloppy_pc_intr()
  ide-tape: always log debug info in idetape_pc_intr() if debugging is enabled
  ide-tape: add ide_tape_io_buffers() helper
  ide-tape: factor out DSC handling from idetape_pc_intr()
  ide-{floppy,tape}: move checking of ->failed_pc to ->callback
  ide: add ide_issue_pc() helper
  ide: add PC_FLAG_DRQ_INTERRUPT pc flag
  ide-scsi: move idescsi_map_sg() call out from idescsi_issue_pc()
  ide: add ide_transfer_pc() helper
  ide-scsi: set drive->scsi flag for devices handled by the driver
  ide-{cd,floppy,tape}: remove checking for drive->scsi
  ide: add PC_FLAG_ZIP_DRIVE pc flag
  ide-tape: factor out waiting for good ireason from idetape_transfer_pc()
  ide-tape: set PC_FLAG_DMA_IN_PROGRESS flag in idetape_transfer_pc()
  ...
2008-07-15 11:15:36 -07:00
FUJITA Tomonori
681a561b7e block: unexport blk_end_sync_rq
All the users of blk_end_sync_rq has gone (they are converted to use
blk_execute_rq). This unexports blk_end_sync_rq.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-07-15 21:21:45 +02:00
FUJITA Tomonori
52a93ba815 block: remove the checking for NULL queue in blk_put_request
Some uses blk_put_request asymmetrically, that is, they uses it with
requests that not allocated by blk_get_request. As a result,
blk_put_request has a hack to catch a NULL request_queue. Now such
callers are fixed (they use blk_get_request properly). So we can
safely remove the hack in blk_put_request.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-07-15 21:21:45 +02:00
Bartlomiej Zolnierkiewicz
9a2d43b756 block: handle blk_pm_resume_request() requests in blk_execute_rq_nowait()
For blk_pm_resume_request() requests (which are used only by IDE subsystem
currently) the queue is stopped so we need to call ->request_fn explicitly.

Thanks to:
- Rafael for reporting/bisecting the bug
- Borislav/Rafael for testing the fix

This is a preparation for converting IDE to use blk_execute_rq().

Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Borislav Petkov <petkovbb@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-07-15 21:21:43 +02:00
Linus Torvalds
666484f025 Merge branch 'core/softirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/softirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  softirq: remove irqs_disabled warning from local_bh_enable
  softirq: remove initialization of static per-cpu variable
  Remove argument from open_softirq which is always NULL
2008-07-14 15:28:42 -07:00
Linus Torvalds
d1794f2c5b Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6
* 'bkl-removal' of git://git.lwn.net/linux-2.6: (146 commits)
  IB/umad: BKL is not needed for ib_umad_open()
  IB/uverbs: BKL is not needed for ib_uverbs_open()
  bf561-coreb: BKL unneeded for open()
  Call fasync() functions without the BKL
  snd/PCM: fasync BKL pushdown
  ipmi: fasync BKL pushdown
  ecryptfs: fasync BKL pushdown
  Bluetooth VHCI: fasync BKL pushdown
  tty_io: fasync BKL pushdown
  tun: fasync BKL pushdown
  i2o: fasync BKL pushdown
  mpt: fasync BKL pushdown
  Remove BKL from remote_llseek v2
  Make FAT users happier by not deadlocking
  x86-mce: BKL pushdown
  vmwatchdog: BKL pushdown
  vmcp: BKL pushdown
  via-pmu: BKL pushdown
  uml-random: BKL pushdown
  uml-mmapper: BKL pushdown
  ...
2008-07-14 14:48:31 -07:00
Jonathan Corbet
2fceef397f Merge commit 'v2.6.26' into bkl-removal 2008-07-14 15:29:34 -06:00
Linus Torvalds
dddec01eb8 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (37 commits)
  splice: fix generic_file_splice_read() race with page invalidation
  ramfs: enable splice write
  drivers/block/pktcdvd.c: avoid useless memset
  cdrom: revert commit 22a9189 (cdrom: use kmalloced buffers instead of buffers on stack)
  scsi: sr avoids useless buffer allocation
  block: blk_rq_map_kern uses the bounce buffers for stack buffers
  block: add blk_queue_update_dma_pad
  DAC960: push down BKL
  pktcdvd: push BKL down into driver
  paride: push ioctl down into driver
  block: use get_unaligned_* helpers
  block: extend queue_flag bitops
  block: request_module(): use format string
  Add bvec_merge_data to handle stacked devices and ->merge_bvec()
  block: integrity flags can't use bit ops on unsigned short
  cmdfilter: extend default read filter
  sg: fix odd style (extra parenthesis) introduced by cmd filter patch
  block: add bounce support to blk_rq_map_user_iov
  cfq-iosched: get rid of enable_idle being unused warning
  allow userspace to modify scsi command filter on per device basis
  ...
2008-07-14 13:15:14 -07:00
James Bottomley
8df5fc042c [SCSI] bsg: fix oops on remove
If you do a modremove of any sas driver, you run into an oops on
shutdown when the host is removed (coming from the host bsg device).
The root cause seems to be that there's a use after free of the
bsg_class_device:  In bsg_kref_release_function, this is used (to do a
put_device(bcg->parent) after bcg->release has been called.  In sas (and
possibly many other things) bcd->release frees the queue which contains
the bsg_class_device, so we get a put_device on unreferenced memory.
Fix this by taking a copy of the pointer to the parent before releasing
bsg.

Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 10:14:56 -05:00
FUJITA Tomonori
3f27e3ed11 [SCSI] bsg: fix bsg_mutex hang with device removal
We don't need to hold bsg_mutex during bsg_complete_all_commands(). It
leads to a problem that we block bsg_unregister_queue during
bsg_complete_all_commands (untill all the outstanding commands
complete).

Thanks to Pete Wyckoff for finding the bug and testing the patch.

The detailed bug report is:

http://marc.info/?l=linux-scsi&m=121182137132145&w=2

Tested-by: Pete Wyckoff <pw@osc.edu>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:23 -05:00
FUJITA Tomonori
30c00eda73 block: blk_rq_map_kern uses the bounce buffers for stack buffers
blk_rq_map_kern is used for kernel internal I/Os. Some callers use
this function with stack buffers but DMA to/from the stack buffers
leads to memory corruption on a non-coherent platform.

This patch make blk_rq_map_kern uses the bounce buffers if a caller
passes a stack buffer (on the all platforms for simplicity).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-04 09:52:13 +02:00
FUJITA Tomonori
27f8221af4 block: add blk_queue_update_dma_pad
This adds blk_queue_update_dma_pad to prevent LLDs from overwriting
the dma pad mask wrongly (we added blk_queue_update_dma_alignment due
to the same reason).

This also converts libata to use blk_queue_update_dma_pad instead of
blk_queue_dma_pad.

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

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:15 +02:00
maximilian attems
e180f59493 block: request_module(): use format string
Avoid bad things happening if the module has a printk control string in
its name.

Signed-off-by: maximilian attems <max@stro.at>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:15 +02:00
Jens Axboe
b24498d477 block: integrity flags can't use bit ops on unsigned short
Just use normal open coded bit operations instead, they need not be
atomic.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:15 +02:00
Adel Gadllah
06a452e5b9 cmdfilter: extend default read filter
This patch adds the commands that the former sg filter allowed for read
access to the cmdfilter to keep userspace apps that rely on them working.

Signed-off-by: Adel Gadllah <adel.gadllah@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:14 +02:00
FUJITA Tomonori
07359fc61b block: add bounce support to blk_rq_map_user_iov
blk_rq_map_user_iov can't handle the bounce buffer (it means that the
bio_map_user_iov path doesn't work with a LLD that needs GFP_DMA).

This patch fixes blk_rq_map_user_iov to support the bounce buffer.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:14 +02:00
Jens Axboe
c265a7f417 cfq-iosched: get rid of enable_idle being unused warning
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:14 +02:00
Adel Gadllah
0b07de85a7 allow userspace to modify scsi command filter on per device basis
This patch exports the per-gendisk command filter to user space through
sysfs, so it can be changed by the system administrator.
All users of the old cmd filter have been converted to use the new one.

Original patch from Peter Jones.

Signed-off-by: Adel Gadllah <adel.gadllah@gmail.com>
Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:14 +02:00
Jens Axboe
b984679efe block: integrity checkpatch cleanups
> 80 char lines and that sort of thing.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:13 +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
Kay Sievers
1c9ce52763 block: export "ro" attribute
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:12 +02:00
Alan D. Brunelle
02c62304e6 Added in user-injected messages into blk traces
This allows a user to annotate the blk trace stream: writing a suitable
message to {/sys/kernel/debug}/block/<dsf>/msg will have it propagated
into the trace stream.

Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:12 +02:00
Jens Axboe
7b679138b3 cfq-iosched: add message logging through blktrace
Now that blktrace has the ability to carry arbitrary messages in
its stream, use that for some CFQ logging.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:12 +02:00
Jens Axboe
863fddcb4b as-iosched: properly protect ioc_gone and ioc count
If we have multiple tasks freeing io contexts when as-iosched
is being unloaded, we could complete() ioc_gone twice. Fix that by
protecting ioc_gone complete() and clearing with a spinlock for
just that purpose. Doesn't matter from a performance perspective,
since it'll only enter that path when ioc_gone != NULL (when as-iosched
is being rmmod'ed).

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:12 +02:00
Jens Axboe
9a11b4ed0e cfq-iosched: properly protect ioc_gone and ioc count
If we have multiple tasks freeing cfq_io_contexts when cfq-iosched
is being unloaded, we could complete() ioc_gone twice. Fix that by
protecting ioc_gone complete() and clearing with a spinlock for
just that purpose. Doesn't matter from a performance perspective,
since it'll only enter that path when ioc_gone != NULL (when cfq-iosched
is being rmmod'ed).

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:12 +02:00
Divyesh Shah
d585d0b9d7 block: Fix the starving writes bug in the anticipatory IO scheduler
AS scheduler alternates between issuing read and write batches. It does
the batch switch only after all requests from the previous batch are
completed.

When switching to a write batch, if there is an on-going read request,
it waits for its completion and indicates its intention of switching by
setting ad->changed_batch and the new direction but does not update the
batch_expire_time for the new write batch which it does in the case of
no previous pending requests.
On completion of the read request, it sees that we were waiting for the
switch and schedules work for kblockd right away and resets the
ad->changed_data flag.
Now when kblockd enters dispatch_request where it is expected to pick
up a write request, it in turn ends the write batch because the
batch_expire_timer was not updated and shows the expire timestamp for
the previous batch.

This results in the write starvation for all the cases where there is
the intention for switching to a write batch, but there is a previous
in-flight read request and the batch gets reverted to a read_batch
right away.

This also holds true in the reverse case (switching from a write batch
to a read batch with an in-flight write request).

I've checked that this bug exists on 2.6.11, 2.6.18, 2.6.24 and
linux-2.6-block git HEAD. I've tested the fix on x86 platforms with
SCSI drives where the driver asks for the next request while a current
request is in-flight.

This patch is based off linux-2.6-block git HEAD.

Bug reproduction:
A simple scenario which reproduces this bug is:
- dd if=/dev/hda3 of=/dev/null &
- lilo
   The lilo takes forever to complete.

This can also be reproduced fairly easily with the earlier dd and
another test
program doing msync().

The example test program below should print out a message after every
iteration
but it simply hangs forever. With this bugfix it makes forward progress.

====
Example test program using msync() (thanks to suleiman AT google DOT
com)

inline uint64_t
rdtsc(void)
{
         int64_t tsc;

         __asm __volatile("rdtsc" : "=A" (tsc));
         return (tsc);
}

int
main(int argc, char **argv)
{
         struct stat st;
         uint64_t e, s, t;
         char *p, q;
         long i;
         int fd;

         if (argc < 2) {
                 printf("Usage: %s <file>\n", argv[0]);
                 return (1);
         }

         if ((fd = open(argv[1], O_RDWR | O_NOATIME)) < 0)
                 err(1, "open");

         if (fstat(fd, &st) < 0)
                 err(1, "fstat");

         p = mmap(NULL, st.st_size, PROT_READ | PROT_WRITE,
MAP_SHARED, fd, 0);

         t = 0;
         for (i = 0; i < 1000; i++) {
                 *p = 0;
                 msync(p, 4096, MS_SYNC);
                 s = rdtsc();
                *p = 0;
                 __asm __volatile(""::: "memory");
                 e = rdtsc();
                 if (argc > 2)
                         printf("%d: %lld cycles %jd %jd\n",
                                i, e - s, (intmax_t)s, (intmax_t)e);
                 t += e - s;
         }
         printf("average time: %lld cycles\n", t / 1000);
         return (0);
}

Cc: <stable@kernel.org>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-01 09:06:42 +02:00
Ingo Molnar
9583f3d9c0 Merge branch 'linus' into core/softirq 2008-06-16 11:24:17 +02:00
Carl Henrik Lunde
14a73f5479 block: disable IRQs until data is written to relay channel
As we may run relay_reserve from interrupt context we must always disable
IRQs.  This is because a call to relay_reserve may expose previously written
data to use space.

Updated new message code and an old but related comment.

Signed-off-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-12 11:20:57 -07:00
Linus Torvalds
d5791d13b1 Fix invalid access errors in blk_lookup_devt
Commit 30f2f0eb4b ("block: do_mounts -
accept root=<non-existant partition>") extended blk_lookup_devt() to be
able to look up partitions that had not yet been registered, but in the
process made the assumption that the '&block_class.devices' list only
contains disk devices and that you can do 'dev_to_disk(dev)' on them.

That isn't actually true.  The block_class device list also contains the
partitions we've discovered so far, and you can't just do a
'dev_to_disk()' on those.

So make sure to only work on devices that block/genhd.c has registered
itself, something we can test by checking the 'dev->type' member.  This
makes the loop in blk_lookup_devt() match the other such loops in this
file.

[ We may want to do an alternate version that knows to handle _either_
  whole-disk devices or partitions, but for now this is the minimal fix
  for a series of crashes reported by Mariusz Kozlowski in

	http://lkml.org/lkml/2008/5/25/25

  and Ingo in

	http://lkml.org/lkml/2008/6/9/39 ]

Reported-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: Neil Brown <neilb@suse.de>
Cc: Joao Luis Meloni Assirati <assirati@nonada.if.usp.br>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-09 10:06:24 -07:00
Jens Axboe
d6de8be711 cfq-iosched: fix RCU problem in cfq_cic_lookup()
cfq_cic_lookup() needs to properly protect ioc->ioc_data before
dereferencing it and also exclude updaters of ioc->ioc_data as well.

Also add a number of comments documenting why the existing RCU usage
is OK.

Thanks a lot to "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> for
review and comments!

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-28 14:49:28 +02:00
Jens Axboe
64565911cd block: make blktrace use per-cpu buffers for message notes
Currently it uses a single static char array, but that risks
being corrupted when multiple users issue message notes at the
same time. Make the buffers dynamically allocated when the trace
is setup and make them per-cpu instead.

The default max message size of 1k is also very large, the
interface is mainly for small text notes. So shrink it to 128 bytes.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-28 14:49:27 +02:00
Alan D. Brunelle
4722dc52a8 Added in elevator switch message to blktrace stream
Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-28 14:49:27 +02:00
Alan D. Brunelle
9d5f09a424 Added in MESSAGE notes for blktraces
Allows messages to be inserted into blktrace streams.

Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-28 14:49:27 +02:00
Richard Kennedy
be754d2c21 block: reorder cfq_queue to save space on 64bit builds
saves 8 bytes of padding & increases objects/slab from 30 to 32 on my
AMD64 config

Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-28 14:49:27 +02:00
Zhang, Yanmin
05caf8dbc1 block: Move the second call to get_request to the end of the loop
In function get_request_wait, the second call to get_request could be
moved to the end of the while loop, because if the first call to
get_request fails, the second call will fail without sleep.

Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-28 14:49:27 +02:00
Carlos R. Mafra
962cf36c5b Remove argument from open_softirq which is always NULL
As git-grep shows, open_softirq() is always called with the last argument
being NULL

block/blk-core.c:       open_softirq(BLOCK_SOFTIRQ, blk_done_softirq, NULL);
kernel/hrtimer.c:       open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq, NULL);
kernel/rcuclassic.c:    open_softirq(RCU_SOFTIRQ, rcu_process_callbacks, NULL);
kernel/rcupreempt.c:    open_softirq(RCU_SOFTIRQ, rcu_process_callbacks, NULL);
kernel/sched.c: open_softirq(SCHED_SOFTIRQ, run_rebalance_domains, NULL);
kernel/softirq.c:       open_softirq(TASKLET_SOFTIRQ, tasklet_action, NULL);
kernel/softirq.c:       open_softirq(HI_SOFTIRQ, tasklet_hi_action, NULL);
kernel/timer.c: open_softirq(TIMER_SOFTIRQ, run_timer_softirq, NULL);
net/core/dev.c: open_softirq(NET_TX_SOFTIRQ, net_tx_action, NULL);
net/core/dev.c: open_softirq(NET_RX_SOFTIRQ, net_rx_action, NULL);

This observation has already been made by Matthew Wilcox in June 2002
(http://www.cs.helsinki.fi/linux/linux-kernel/2002-25/0687.html)

"I notice that none of the current softirq routines use the data element
passed to them."

and the situation hasn't changed since them. So it appears we can safely
remove that extra argument to save 128 (54) bytes of kernel data (text).

Signed-off-by: Carlos R. Mafra <crmafra@ift.unesp.br>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 07:43:15 +02:00
Jonathan Corbet
75bd2ef145 bsg: cdev lock_kernel() pushdown
Push the cdev lock_kernel call into bsg_open().

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-05-18 15:43:40 -06:00
Neil Brown
e7e72bf641 Remove blkdev warning triggered by using md
As setting and clearing queue flags now requires that we hold a spinlock
on the queue, and as blk_queue_stack_limits is called without that lock,
get the lock inside blk_queue_stack_limits.

For blk_queue_stack_limits to be able to find the right lock, each md
personality needs to set q->queue_lock to point to the appropriate lock.
Those personalities which didn't previously use a spin_lock, us
q->__queue_lock.  So always initialise that lock when allocated.

With this in place, setting/clearing of the QUEUE_FLAG_PLUGGED bit will no
longer cause warnings as it will be clear that the proper lock is held.

Thanks to Dan Williams for review and fixing the silly bugs.

Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Alistair John Strachan <alistair@devzero.co.uk>
Cc: Nick Piggin <npiggin@suse.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Jacek Luczak <difrost.kernel@gmail.com>
Cc: Prakash Punnoor <prakash@punnoor.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14 19:11:15 -07:00
Kay Sievers
30f2f0eb4b block: do_mounts - accept root=<non-existant partition>
Some devices, like md, may create partitions only at first access,
so allow root= to be set to a valid non-existant partition of an
existing disk. This applies only to non-initramfs root mounting.

This fixes a regression from 2.6.24 which did allow this to happen and
broke some users machines :(

Acked-by: Neil Brown <neilb@suse.de>
Tested-by: Joao Luis Meloni Assirati <assirati@nonada.if.usp.br>
Cc: stable <stable@kernel.org>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-05-14 10:37:57 -07:00
Jean Delvare
f36f21ecca Fix misuses of bdevname()
bdevname() fills the buffer that it is given as a parameter, so calling
strcpy() or snprintf() on the returned value is redundant (and probably not
guaranteed to work - I don't think strcpy and snprintf support overlapping
buffers.)

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-13 08:02:26 -07:00
Jens Axboe
28f13702f0 block: avoid duplicate calls to get_part() in disk stat code
get_part() is fairly expensive, as it O(N) loops over partitions
to find the right one. In lots of normal IO paths we end up looking
up the partition twice, to make matters even worse. Change the
stat add code to accept a passed in partition instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 10:15:46 +02:00
Jens Axboe
6d63c27557 cfq-iosched: make io priorities inherit CPU scheduling class as well as nice
We currently set all processes to the best-effort scheduling class,
regardless of what CPU scheduling class they belong to. Improve that
so that we correctly track idle and rt scheduling classes as well.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 09:51:23 +02:00
Jens Axboe
dbaf2c003e block: optimize generic_unplug_device()
Original patch from Mikulas Patocka <mpatocka@redhat.com>

Mike Anderson was doing an OLTP benchmark on a computer with 48 physical
disks mapped to one logical device via device mapper.

He found that there was a slowdown on request_queue->lock in function
generic_unplug_device. The slowdown is caused by the fact that when some
code calls unplug on the device mapper, device mapper calls unplug on all
physical disks. These unplug calls take the lock, find that the queue is
already unplugged, release the lock and exit.

With the below patch, performance of the benchmark was increased by 18%
(the whole OLTP application, not just block layer microbenchmarks).

So I'm submitting this patch for upstream. I think the patch is correct,
because when more threads call simultaneously plug and unplug, it is
unspecified, if the queue is or isn't plugged (so the patch can't make
this worse). And the caller that plugged the queue should unplug it
anyway. (if it doesn't, there's 3ms timeout).

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 09:48:17 +02:00
Jens Axboe
2cdf79cafb block: get rid of likely/unlikely predictions in merge logic
They tend to depend a lot on the workload, so not a clear-cut
likely or unlikely fit.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 09:33:55 +02:00
Jens Axboe
07416d29bc cfq-iosched: fix RCU race in the cfq io_context destructor handling
put_io_context() drops the RCU read lock before calling into cfq_dtor(),
however we need to hold off freeing there before grabbing and
dereferencing the first object on the list.

So extend the rcu_read_lock() scope to cover the calling of cfq_dtor(),
and optimize cfq_free_io_context() to use a new variant for
call_for_each_cic() that assumes the RCU read lock is already held.

Hit in the wild by Alexey Dobriyan <adobriyan@gmail.com>

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 09:28:57 +02:00
Jens Axboe
aa94b5371f block: adjust tagging function queue bit locking
For most initialization purposes, calling blk_queue_init_tags() without
the queue lock held is OK. Only if called for resizing an existing map
must the lock be held. Ditto for tag cleanup, the maps are reference
counted.

So switch the general queue flag setting to the unlocked variant, but
retain the locked variant for resizing.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 09:27:43 +02:00
Jens Axboe
bf0f97025c block: sysfs store function needs to grab queue_lock and use queue_flag_*()
Concurrency isn't a big deal here since we have requests in flight
at this point, but do the locked variant to set a better example.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-07 09:09:39 +02:00
Linus Torvalds
d626e3bf72 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6:
  [SCSI] aic94xx: fix section mismatch
  [SCSI] u14-34f: Fix 32bit only problem
  [SCSI] dpt_i2o: sysfs code
  [SCSI] dpt_i2o: 64 bit support
  [SCSI] dpt_i2o: move from virt_to_bus/bus_to_virt to dma_alloc_coherent
  [SCSI] dpt_i2o: use standard __init / __exit code
  [SCSI] megaraid_sas: fix suspend/resume sections
  [SCSI] aacraid: Add Power Management support
  [SCSI] aacraid: Fix jbod operations scan issues
  [SCSI] aacraid: Fix warning about macro side-effects
  [SCSI] add support for variable length extended commands
  [SCSI] Let scsi_cmnd->cmnd use request->cmd buffer
  [SCSI] bsg: add large command support
  [SCSI] aacraid: Fix down_interruptible() to check the return value correctly
  [SCSI] megaraid_sas; Update the Version and Changelog
  [SCSI] ibmvscsi: Handle non SCSI error status
  [SCSI] bug fix for free list handling
  [SCSI] ipr: Rename ipr's state scsi host attribute to prevent collisions
  [SCSI] megaraid_mbox: fix Dell CERC firmware problem
2008-05-02 13:52:35 -07:00
Boaz Harrosh
db4742dd8f [SCSI] add support for variable length extended commands
Add support for variable-length, extended, and vendor specific
CDBs to scsi-ml. It is now possible for initiators and ULD's
to issue these types of commands. LLDs need not change much.
All they need is to raise the .max_cmd_len to the longest command
they support (see iscsi patch).

- clean-up some code paths that did not expect commands to be
  larger than 16, and change cmd_len members' type to short as
  char is not enough.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-05-02 11:33:25 -05:00
FUJITA Tomonori
9f5de6b105 [SCSI] bsg: add large command support
This enables bsg to handle the request length larger than BLK_MAX_CDB
(mainly for the variable length CDB format).

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>
2008-05-02 10:17:35 -05:00
Harvey Harrison
24c03d47d0 block: remove remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:04:02 -07:00
Peter Zijlstra
cf0ca9fe5d mm: bdi: export BDI attributes in sysfs
Provide a place in sysfs (/sys/class/bdi) for the backing_dev_info object.
This allows us to see and set the various BDI specific variables.

In particular this properly exposes the read-ahead window for all relevant
users and /sys/block/<block>/queue/read_ahead_kb should be deprecated.

With patient help from Kay Sievers and Greg KH

[mszeredi@suse.cz]

 - split off NFS and FUSE changes into separate patches
 - document new sysfs attributes under Documentation/ABI
 - do bdi_class_init as a core_initcall, otherwise the "default" BDI
   won't be initialized
 - remove bdi_init_fmt macro, it's not used very much

[akpm@linux-foundation.org: fix ia64 warning]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Greg KH <greg@kroah.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:49 -07:00
Alan D. Brunelle
ac9fafa124 block: Skip I/O merges when disabled
The block I/O + elevator + I/O scheduler code spend a lot of time trying
to merge I/Os -- rightfully so under "normal" circumstances. However,
if one were to know that the incoming I/O stream was /very/ random in
nature, the cycles are wasted.

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

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

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

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:55 +02:00
FUJITA Tomonori
d34c87e4ba block: replace sizeof(rq->cmd) with BLK_MAX_CDB
This is a preparation for changing rq->cmd from the static array to a
pointer.

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

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

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:55 +02:00
FUJITA Tomonori
992b5bceee block: no need to initialize rq->cmd with blk_get_request
blk_get_request initializes rq->cmd (rq_init does) so the users don't
need to do that.

The purpose of this patch is to remove sizeof(rq->cmd) and &rq->cmd,
as a preparation for large command support, which changes rq->cmd from
the static array to a pointer. sizeof(rq->cmd) will not make sense and
&rq->cmd won't work.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:55 +02:00
Adrian Bunk
6f6a036e6e block/blk-barrier.c:blk_ordered_cur_seq() mustn't be inline
This patch fixes the following build error with UML and gcc 4.3:

<--  snip  -->

...
  CC      block/blk-barrier.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/blk-barrier.c: In function ‘blk_do_ordered’:
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/blk-barrier.c:57: sorry, unimplemented: inlining failed in call to ‘blk_ordered_cur_seq’: function body not available
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/blk-barrier.c:252: sorry, unimplemented: called from here
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/blk-barrier.c:57: sorry, unimplemented: inlining failed in call to ‘blk_ordered_cur_seq’: function body not available
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/blk-barrier.c:253: sorry, unimplemented: called from here
make[2]: *** [block/blk-barrier.o] Error 1

<--  snip  -->

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:54 +02:00
Adrian Bunk
72ed0bf60a block/elevator.c:elv_rq_merge_ok() mustn't be inline
This patch fixes the following build error with UML and gcc 4.3:

<--  snip  -->

...
  CC      block/elevator.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c: In function ‘elv_merge’:
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c:73: sorry, unimplemented: inlining failed in call to ‘elv_rq_merge_ok’: function body not available
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c:103: sorry, unimplemented: called from here
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c:73: sorry, unimplemented: inlining failed in call to ‘elv_rq_merge_ok’: function body not available
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c:495: sorry, unimplemented: called from here
make[2]: *** [block/elevator.o] Error 1
make[1]: *** [block] Error 2

<--  snip  -->

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:54 +02:00
Nick Piggin
75ad23bc0f block: make queue flags non-atomic
We can save some atomic ops in the IO path, if we clearly define
the rules of how to modify the queue flags.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:33 +02:00
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
Adrian Bunk
657e93be35 unexport blk_max_pfn
blk_max_pfn can now be unexported.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 09:50:34 +02:00
FUJITA Tomonori
1afb20f301 block: make rq_init() do a full memset()
This requires moving rq_init() from get_request() to blk_alloc_request().
The upside is that we can now require an rq_init() from any path that
wishes to hand the request to the block layer.

rq_init() will be exported for the code that uses struct request
without blk_get_request.

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

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 09:50:34 +02:00
FUJITA Tomonori
97f46ae45c [SCSI] bsg: add release callback support
This patch adds release callback support, which is called when a bsg
device goes away. bsg_register_queue() takes a pointer to a callback
function. This feature is useful for stuff like sas_host that can't
use the release callback in struct device.

If a caller doesn't need bsg's release callback, it can call
bsg_register_queue() with NULL pointer (e.g. scsi devices can use
release callback in struct device so they don't need bsg's callback).

With this patch, bsg uses kref for refcounts on bsg devices instead of
get/put_device in fops->open/release. bsg calls put_device and the
caller's release callback (if it was registered) in kref_put's
release.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-22 15:16:32 -05:00
Linus Torvalds
548453fd10 Merge branch 'for-2.6.26' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.26' of git://git.kernel.dk/linux-2.6-block:
  block: fix blk_register_queue() return value
  block: fix memory hotplug and bouncing in block layer
  block: replace remaining __FUNCTION__ occurrences
  Kconfig: clean up block/Kconfig help descriptions
  cciss: fix warning oops on rmmod of driver
  cciss: Fix race between disk-adding code and interrupt handler
  block: move the padding adjustment to blk_rq_map_sg
  block: add bio_copy_user_iov support to blk_rq_map_user_iov
  block: convert bio_copy_user to bio_copy_user_iov
  loop: manage partitions in disk image
  cdrom: use kmalloced buffers instead of buffers on stack
  cdrom: make unregister_cdrom() return void
  cdrom: use list_head for cdrom_device_info list
  cdrom: protect cdrom_device_info list by mutex
  cdrom: cleanup hardcoded error-code
  cdrom: remove ifdef CONFIG_SYSCTL
2008-04-21 16:03:40 -07:00
Akinobu Mita
fb19974630 block: fix blk_register_queue() return value
blk_register_queue() returns -ENXIO when queue->request_fn is NULL.  But there
are some block drivers that call blk_register_queue() via add_disk() with
queue->request_fn == NULL.  (For example, brd, loop)

Although no one checks return value of blk_register_queue(), this patch makes
it return 0 instead of -ENXIO when queue->request_fn is NULL,

Also this patch adds warning when blk_register_queue() and
blk_unregister_queue() are called with queue == NULL rather than ignore
invalid usage silently.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-21 09:51:06 +02:00
Nick Andrew
ee86418d39 Kconfig: clean up block/Kconfig help descriptions
Modify the help descriptions of block/Kconfig for clarity, accuracy and
consistency.

Refactor the BLOCK description a bit.  The wording "This permits ...  to be
removed" isn't quite right; the block layer is removed when the option is
disabled, whereas most descriptions talk about what happens when the option is
enabled.  Reformat the list of what is affected by disabling the block layer.

Add more examples of large block devices to LBD and strive for technical
accuracy; block devices of size _exactly_ 2TB require CONFIG_LBD, not only
"bigger than 2TB".  Also try to say (perhaps not very clearly) that the config
option is only needed when you want to have individual block devices of size
>= 2TB, for example if you had 3 x 1TB disks in your computer you'd have a
total storage size of 3TB but you wouldn't need the option unless you want to
aggregate those disks into a RAID or LVM.

Improve terminology and grammar on BLK_DEV_IO_TRACE.

I also added the boilerplate "If unsure, say N" to most options.

Precisely say "2TB and larger" for LSF.

Indent the help text for BLK_DEV_BSG by 2 spaces in accordance with the
standard.

Signed-off-by: Nick Andrew <nick@nick-andrew.net>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-21 09:51:04 +02:00
FUJITA Tomonori
f18573abcc block: move the padding adjustment to blk_rq_map_sg
blk_rq_map_user adjusts bi_size of the last bio. It breaks the rule
that req->data_len (the true data length) is equal to sum(bio). It
broke the scsi command completion code.

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

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

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

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

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-21 09:50:08 +02:00
FUJITA Tomonori
afdc1a780e block: add bio_copy_user_iov support to blk_rq_map_user_iov
With this patch, blk_rq_map_user_iov uses bio_copy_user_iov when a low
level driver needs padding or a buffer in sg_iovec isn't aligned. That
is, it uses temporary kernel buffers instead of mapping user pages
directly.

When a LLD needs padding, later blk_rq_map_sg needs to extend the last
entry of a scatter list. bio_copy_user_iov guarantees that there is
enough space for padding by using temporary kernel buffers instead of
user pages.

blk_rq_map_user_iov needs buffers in sg_iovec to be aligned. The
comment in blk_rq_map_user_iov indicates that drivers/scsi/sg.c also
needs buffers in sg_iovec to be aligned. Actually, drivers/scsi/sg.c
works with unaligned buffers in sg_iovec (it always uses temporary
kernel buffers).

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
Tony Jones
ee959b00c3 SCSI: convert struct class_device to struct device
It's big, but there doesn't seem to be a way to split it up smaller...

Signed-off-by: Tony Jones <tonyj@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-19 19:10:33 -07:00
Linus Torvalds
2cca775bae Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (137 commits)
  [SCSI] iscsi: bidi support for iscsi_tcp
  [SCSI] iscsi: bidi support at the generic libiscsi level
  [SCSI] iscsi: extended cdb support
  [SCSI] zfcp: Fix error handling for blocked unit for send FCP command
  [SCSI] zfcp: Remove zfcp_erp_wait from slave destory handler to fix deadlock
  [SCSI] zfcp: fix 31 bit compile warnings
  [SCSI] bsg: no need to set BSG_F_BLOCK bit in bsg_complete_all_commands
  [SCSI] bsg: remove minor in struct bsg_device
  [SCSI] bsg: use better helper list functions
  [SCSI] bsg: replace kobject_get with blk_get_queue
  [SCSI] bsg: takes a ref to struct device in fops->open
  [SCSI] qla1280: remove version check
  [SCSI] libsas: fix endianness bug in sas_ata
  [SCSI] zfcp: fix compiler warning caused by poking inside new semaphore (linux-next)
  [SCSI] aacraid: Do not describe check_reset parameter with its value
  [SCSI] aacraid: Fix down_interruptible() to check the return value
  [SCSI] sun3_scsi_vme: add MODULE_LICENSE
  [SCSI] st: rename flush_write_buffer()
  [SCSI] tgt: use KMEM_CACHE macro
  [SCSI] initio: fix big endian problems for auto request sense
  ...
2008-04-18 11:25:31 -07:00
FUJITA Tomonori
99773aab03 [SCSI] bsg: no need to set BSG_F_BLOCK bit in bsg_complete_all_commands
Before bsg_complete_all_commands is called, BSG_F_BLOCK bit is always
set.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-18 11:48:43 -05:00
FUJITA Tomonori
842ea771c3 [SCSI] bsg: remove minor in struct bsg_device
minor in struct bsg_device is used as identifier to find the
corresponding struct bsg_device_class. However, request_queuse can be
used as identifier for that and the minor in struct bsg_device is
unnecessary.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-18 11:48:26 -05:00
FUJITA Tomonori
43ac9e62c4 [SCSI] bsg: use better helper list functions
This replace hlist_for_each and list_entry with hlist_for_each_entry
and list_first_entry respectively.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-18 11:48:08 -05:00
FUJITA Tomonori
c3ff1b90d8 [SCSI] bsg: replace kobject_get with blk_get_queue
Both takes a ref to a queue. But blk_get_queue checks QUEUE_FLAG_DEAD
and is more appropriate interface here.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-18 11:47:49 -05:00
FUJITA Tomonori
d45ac4fa8f [SCSI] bsg: takes a ref to struct device in fops->open
bsg_register_queue() takes a ref to struct device that a caller
passes. For example, bsg takes a ref to the sdev_gendev for scsi
devices. However, bsg doesn't inrease the refcount in fops->open. So
while an application opens a bsg device, the scsi device that the bsg
device holds can go away (bsg also takes a ref to a queue, but it
doesn't prevent the device from going away).

With this patch, bsg increases the refcount of struct device in
fops->open and decreases it in fops->release.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-18 11:47:19 -05:00
Bartlomiej Zolnierkiewicz
93de00fd1c ide: remove broken/dangerous HDIO_[UNREGISTER,SCAN]_HWIF ioctls (take 3)
hdparm explicitely marks HDIO_[UNREGISTER,SCAN]_HWIF ioctls as DANGEROUS
and given the number of bugs we can assume that there are no real users:

* DMA has no chance of working because DMA resources are released by
  ide_unregister() and they are never allocated again.

* Since ide_init_hwif_ports() is used for ->io_ports[] setup the ioctls
  don't work for almost all hosts with "non-standard" (== non ISA-like)
  layout of IDE taskfile registers (there is a lot of such host drivers).

* ide_port_init_devices() is not called when probing IDE devices so:
  - drive->autotune is never set and IDE host/devices are not programmed
    for the correct PIO/DMA transfer modes (=> possible data corruption)
  - host specific I/O 32-bit and IRQ unmasking settings are not applied
    (=> possible data corruption)
  - host specific ->port_init_devs method is not called (=> no luck with
    ht6560b, qd65xx and opti621 host drivers)

* ->rw_disk method is not preserved (=> no HPT3xxN chipsets support).

* ->serialized flag is not preserved (=> possible data corruption when
   using icside, aec62xx (ATP850UF chipset), cmd640, cs5530, hpt366
   (HPT3xxN chipsets), rz1000, sc1200, dtc2278 and ht6560b host drivers).

* ->ack_intr method is not preserved (=> needed by ide-cris, buddha,
  gayle and macide host drivers).

* ->sata_scr[] and sata_misc[] is cleared by ide_unregister() and it
  isn't initialized again (SiI3112 support needs them).

* To issue an ioctl() there need to be at least one IDE device present
  in the system.

* ->cable_detect method is not preserved + it is not called when probing
  IDE devices so cable detection is broken (however since DMA support is
  also broken it doesn't really matter ;-).

* Some objects which may have already been freed in ide_unregister()
  are restored by ide_hwif_restore() (i.e. ->hwgroup).

* ide_register_hw() may unregister unrelated IDE ports if free ide_hwifs[]
  slot cannot be found.

* When IDE host drivers are modular unregistered port may be re-used by
  different host driver that owned it first causing subtle bugs.

Since we now have a proper warm-plug support remove these ioctls,
then remove no longer needed:
- ide_register_hw() and ide_hwif_restore() functions
- 'init_default' and 'restore' arguments of ide_unregister()
- zeroeing of hwif->{dma,extra}_* fields in ide_unregister()

As an added bonus IDE core code size shrinks by ~3kB (x86-32).

v2:
* fix ide_unregister() arguments in cleanup_module() (Andrew Morton).

v3:
* fix ide_unregister() arguments in palm_bk3710.c.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-04-18 00:46:24 +02:00
Jens Axboe
75ce6faccd block: update git url for blktrace
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-15 10:23:35 +02:00
Fabio Checconi
4faa3c8150 cfq-iosched: do not leak ioc_data across iosched switches
When switching scheduler from cfq, cfq_exit_queue() does not clear
ioc->ioc_data, leaving a dangling pointer that can deceive the following
lookups when the iosched is switched back to cfq.  The pattern that can
trigger that is the following:

    - elevator switch from cfq to something else;
    - module unloading, with elv_unregister() that calls cfq_free_io_context()
      on ioc freeing the cic (via the .trim op);
    - module gets reloaded and the elevator switches back to cfq;
    - reallocation of a cic at the same address as before (with a valid key).

To fix it just assign NULL to ioc_data in __cfq_exit_single_io_context(),
that is called from the regular exit path and from the elevator switching
code.  The only path that frees a cic and is not covered is the error handling
one, but cic's freed in this way are never cached in ioc_data.

Signed-off-by: Fabio Checconi <fabio@gandalf.sssup.it>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-10 08:28:01 +02:00
Fabio Checconi
34e6bbf23c cfq-iosched: fix rcu freeing of cfq io contexts
SLAB_DESTROY_BY_RCU is not a direct substitute for normal call_rcu()
freeing, since it'll page freeing but NOT object freeing. So change
cfq to do the freeing on its own.

Signed-off-by: Fabio Checconi <fabio@gandalf.sssup.it>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-02 15:42:20 +02:00
Andrea Arcangeli
00d61e3e8c Fix bounce setting for 64-bit
Looking a bit closer into this regression the reason this can't be
right is that dma_addr common default is BLK_BOUNCE_HIGH and most
machines have less than 4G. So if you do:

    if (b_pfn <= (min_t(u64, 0xffffffff, BLK_BOUNCE_HIGH) >> PAGE_SHIFT))
	dma = 1

that will translate to:

     if (BLK_BOUNCE_HIGH <= BLK_BOUNCE_HIGH)
     	dma = 1

So for 99% of hardware this will trigger unnecessary GFP_DMA
allocations and isa pooling operations.

Also note how the 32bit code still does b_pfn < blk_max_low_pfn.

I guess this is what you were looking after. I didn't verify but as
far as I can tell, this will stop the regression with isa dma
operations at boot for 99% of blkdev/memory combinations out there and
I guess this fixes the setups with >4G of ram and 32bit pci cards as
well (this also retains symmetry with the 32bit code).

Signed-off-by: Andrea Arcangeli <andrea@qumranet.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-02 09:06:44 +02:00
Roland McGrath
ee27a558ae genhd must_check warning fix
Fixes:

	block/genhd.c:361: warning: ignoring return value of ‘class_register’, declared with attribute warn_unused_result

Signed-off-by: Roland McGrath <roland@redhat.com>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-12 12:34:37 -07:00
Jens Axboe
cc66b4512c block: fix blkdev_issue_flush() not detecting and passing EOPNOTSUPP back
This is important to eg dm, that tries to decide whether to stop using
barriers or not.

Tested as working by Anders Henke <anders.henke@1und1.de>

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:47:46 +01:00
Harvey Harrison
56d94a37f6 block: fix shadowed variable warning in blk-map.c
Introduced between 2.6.25-rc2 and -rc3
block/blk-map.c:154:14: warning: symbol 'bio' shadows an earlier one
block/blk-map.c:110:13: originally declared here

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:31:22 +01:00
Harvey Harrison
448da4d262 block: remove extern on function definition
Intoduced between 2.6.25-rc2 and -rc3
block/blk-settings.c:319:12: warning: function 'blk_queue_dma_drain' with external linkage has definition

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:30:18 +01:00
Adrian Bunk
bec419404a unexport blk_rq_map_user_iov
This patch removes the unused export of blk_rq_map_user_iov.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:28:34 +01:00
Adrian Bunk
9d7f1e6b9b unexport blk_{get,put}_queue
This patch removes the unused exports of blk_{get,put}_queue.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:28:32 +01:00
Adrian Bunk
1826eadfc4 block/genhd.c: cleanups
This patch contains the following cleanups:
- make the needlessly global struct disk_type static
- #if 0 the unused genhd_media_change_notify()

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:28:31 +01:00
Adrian Bunk
ff88972c85 proper prototype for blk_dev_init()
This patch adds a proper prototye for blk_dev_init() in block/blk.h

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:28:29 +01:00
Adrian Bunk
278caf0120 block/blk-tag.c should #include "blk.h"
Every file should include the headers containing the externs for its
global functions (in this case for __blk_queue_free_tags()).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:28:24 +01:00
Yang Shi
419c434c35 Fix DMA access of block device in 64-bit kernel on some non-x86 systems with 4GB or upper 4GB memory
For some non-x86 systems with 4GB or upper 4GB memory,
we need increase the range of addresses that can be
used for direct DMA in 64-bit kernel.

Signed-off-by: Yang Shi <yang.shi@windriver.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:20:51 +01:00
Tejun Heo
e3790c7d42 block: separate out padding from alignment
Block layer alignment was used for two different purposes - memory
alignment and padding.  This causes problems in lower layers because
drivers which only require memory alignment ends up with adjusted
rq->data_len.  Separate out padding such that padding occurs iff
driver explicitly requests it.

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

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

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

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
2008-03-04 11:17:11 +01:00
Randy Dunlap
5d87a052c7 block: fix kernel-docbook parameters and files
kernel-doc for block/:
- add missing parameters
- fix one function's parameter list (remove blank line)
- add 2 source files to docbook for non-exported kernel-doc functions

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-04 11:14:39 +01:00
Tejun Heo
db0a2e0099 block: clear drain buffer if draining for write command
Clear drain buffer before chaining if the command in question is a
write.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:36:55 +01:00
Tejun Heo
2fb98e8414 block: implement request_queue->dma_drain_needed
Draining shouldn't be done for commands where overflow may indicate
data integrity issues.  Add dma_drain_needed callback to
request_queue.  Drain buffer is appened iff this function returns
non-zero.

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

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

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

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:36:35 +01:00
Tejun Heo
40b01b9bbd block: update bio according to DMA alignment padding
DMA start address and transfer size alignment for PC requests are
achieved using bio_copy_user() instead of bio_map_user().  This works
because bio_copy_user() always uses full pages and block DMA alignment
isn't allowed to go over PAGE_SIZE.

However, the implementation didn't update the last bio of the request
to make this padding visible to lower layers.  This patch makes
blk_rq_map_user() extend the last bio such that it includes the
padding area and the size of area pointed to by the request is
properly aligned.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:35:38 +01:00
Jens Axboe
e164094964 elevator: make elevator_get() attempt to load the appropriate module
Currently we fail if someone requests a valid io scheduler, but it's
modular and not currently loaded. That can happen from a driver init
asking for a different scheduler, or online switching through sysfs
as requested by a user.

This patch makes elevator_get() request_module() to attempt to load
the appropriate module, instead of requiring that done manually.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 10:20:37 +01:00
Jens Axboe
ffc4e75957 cfq-iosched: add hlist for browsing parallel to the radix tree
It's cumbersome to browse a radix tree from start to finish, especially
since we modify keys when a process exits. So add a hlist for the single
purpose of browsing over all known cfq_io_contexts, used for exit,
io prio change, etc.

This fixes http://bugzilla.kernel.org/show_bug.cgi?id=9948

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 10:04:00 +01:00
Jens Axboe
84e9e03c55 block: make blk_rq_map_user() clear ->bio if it unmaps it
That way the interface is symmetric, and calling blk_rq_unmap_user()
on the request wont oops.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 10:04:00 +01:00
Adrian Bunk
52ff4cae65 make blk_settings_init() static
blk_settings_init() can become static.

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
Adrian Bunk
1334159826 make blk_ioc_init() static
blk_ioc_init() can become static.

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
Adrian Bunk
5ece6c52ea make blk-core.c:request_cachep static again
request_cachep needlessly became global.

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
Jerome Marchand
c3c930d933 Enhanced partition statistics: remove old partition statistics
Removes the now unused old partition statistic code.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-08 12:42:01 +01:00
Jerome Marchand
28f39d553e Enhanced partition statistics: procfs
Reports enhanced partition statistics in /proc/diskstats.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
2008-02-08 12:42:00 +01:00
Jerome Marchand
6f2576af5b Enhanced partition statistics: update partition statitics
Updates the enhanced partition statistics in generic block layer
besides the disk statistics.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-08 12:41:56 +01:00
Jens Axboe
63a7138671 block: fixup rq_init() a bit
Rearrange fields in cache order and initialize some fields that
we didn't previously init. Remove init of ->completion_data, it's
part of a union with ->hash. Luckily clearing the rb node is the same
as setting it to null!

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

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

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-01 11:34:49 +01:00
Jens Axboe
8bdd3f8a69 as-iosched: fix inconsistent ioc->lock context
Since it's acquired from irq context, all locking must be of the
irq safe variant. Most are already inside the queue lock (which
already disables interrupts), but the io scheduler rmmod path
always has irqs enabled and the put_io_context() path may legally
be called with irqs enabled (even if it isn't usually). So fixup
those two.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-01 09:44:28 +01:00
Jens Axboe
4eb166d987 block: make elevator lib checkpatch compliant
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-01 09:26:33 +01:00
Jens Axboe
fe094d98e7 cfq-iosched: make checkpatch compliant
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-01 09:26:33 +01:00
Jens Axboe
6728cb0e63 block: make core bits checkpatch compliant
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-01 09:26:33 +01:00
Jens Axboe
22b132102f block: new end request handling interface should take unsigned byte counts
No point in passing signed integers as the byte count, they can never
be negative.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-01 09:26:33 +01:00
James Bottomley
40f620286d [SCSI] bsg: copy the cmd_type field to the subordinate request for bidi
This fixes a problem in SCSI where we use the (previously
uninitialised) cmd_type via blk_pc_request() to set up the transfer in
scsi_init_sgtable().

Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-30 13:14:26 -06:00
Jens Axboe
149a051f82 as-iosched: fix double locking bug in as_merged_requests()
If the two requests belong to the same io context, we will attempt
to lock the same lock twice. But swapping contexts is pointless in
that case, so just check for rioc == nioc before doing the double
lock and copy.

Tested-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-30 09:11:10 +01:00
Jan Engelhardt
12f32bb317 block: constify function pointer tables
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:19 +01:00
Martin K. Petersen
e68b903c6b Expose hardware sector size
Expose hardware sector size in sysfs queue directory.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:17 +01:00
Jens Axboe
d6d4819696 block: ll_rw_blk.c split, add blk-merge.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:12 +01:00
Jens Axboe
db1d08c646 block: remove dated (and wrong) comment in blk-core.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:11 +01:00
Jens Axboe
26b8256e2b block: get rid of unnecessary forward declarations in blk-core.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:09 +01:00
Jens Axboe
86db1e2977 block: continue ll_rw_blk.c splitup
Adds files for barrier handling, rq execution, io context handling,
mapping data to requests, and queue settings.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:08 +01:00
Jens Axboe
8324aa91d1 block: split tag and sysfs handling from blk-core.c
Seperates the tag and sysfs handling from ll_rw_blk.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:07 +01:00
Jens Axboe
a168ee84c9 block: first step of splitting ll_rw_blk, rename it
Then we retain history in blk-core.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-29 21:55:05 +01:00
Linus Torvalds
8d01eddf29 Merge branch 'for-2.6.25' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.25' of git://git.kernel.dk/linux-2.6-block:
  block: implement drain buffers
  __bio_clone: don't calculate hw/phys segment counts
  block: allow queue dma_alignment of zero
  blktrace: Add blktrace ioctls to SCSI generic devices
2008-01-29 08:51:56 +11:00
Linus Torvalds
f0f0052069 Merge branch 'blk-end-request' of git://git.kernel.dk/linux-2.6-block
* 'blk-end-request' of git://git.kernel.dk/linux-2.6-block: (30 commits)
  blk_end_request: changing xsysace (take 4)
  blk_end_request: changing ub (take 4)
  blk_end_request: cleanup of request completion (take 4)
  blk_end_request: cleanup 'uptodate' related code (take 4)
  blk_end_request: remove/unexport end_that_request_* (take 4)
  blk_end_request: changing scsi (take 4)
  blk_end_request: add bidi completion interface (take 4)
  blk_end_request: changing ide-cd (take 4)
  blk_end_request: add callback feature (take 4)
  blk_end_request: changing ide normal caller (take 4)
  blk_end_request: changing cpqarray (take 4)
  blk_end_request: changing cciss (take 4)
  blk_end_request: changing ide-scsi (take 4)
  blk_end_request: changing s390 (take 4)
  blk_end_request: changing mmc (take 4)
  blk_end_request: changing i2o_block (take 4)
  blk_end_request: changing viocd (take 4)
  blk_end_request: changing xen-blkfront (take 4)
  blk_end_request: changing viodasd (take 4)
  blk_end_request: changing sx8 (take 4)
  ...
2008-01-29 08:51:32 +11:00
Jens Axboe
febffd6181 cfq-iosched: kill some big inlines
Use of inlines were a bit over the top, trim them down a bit.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 13:19:43 +01:00
Jens Axboe
0871714e08 cfq-iosched: relax IOPRIO_CLASS_IDLE restrictions
Currently you must be root to set idle io prio class on a process. This
is due to the fact that the idle class is implemented as a true idle
class, meaning that it will not make progress if someone else is
requesting disk access. Unfortunately this means that it opens DOS
opportunities by locking down file system resources, hence it is root
only at the moment.

This patch relaxes the idle class a little, by removing the truly idle
part (which entals a grace period with associated timer). The
modifications make the idle class as close to zero impact as can be done
while still guarenteeing progress. This means we can relax the root only
criteria as well.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 11:38:15 +01:00
James Bottomley
fa0ccd837e block: implement drain buffers
These DMA drain buffer implementations in drivers are pretty horrible
to do in terms of manipulating the scatterlist.  Plus they're being
done at least in drivers/ide and drivers/ata, so we now have code
duplication.

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

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

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

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:54:11 +01:00
Jens Axboe
521f3bbdba io_context sharing - anticipatory changes
changes to anticipatory io scheduler for io_context sharing

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:50:35 +01:00
Jens Axboe
4ac845a2e9 block: cfq: make the io contect sharing lockless
The io context sharing introduced a per-ioc spinlock, that would protect
the cfq io context lookup. That is a regression from the original, since
we never needed any locking there because the ioc/cic were process private.

The cic lookup is changed from an rbtree construct to a radix tree, which
we can then use RCU to make the reader side lockless. That is the performance
critical path, modifying the radix tree is only done on process creation
(when that process first does IO, actually) and on process exit (if that
process has done IO).

As it so happens, radix trees are also much faster for this type of
lookup where the key is a pointer. It's a very sparse tree.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:50:33 +01:00
Nikanth Karthikesan
66dac98ed0 io_context sharing - cfq changes
changes in the cfq for io_context sharing

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:50:32 +01:00
Jens Axboe
d38ecf935f io context sharing: preliminary support
Detach task state from ioc, instead keep track of how many processes
are accessing the ioc.

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

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:50:29 +01:00
Kiyoshi Ueda
b8286239dd blk_end_request: cleanup of request completion (take 4)
This patch merges complete_request() into end_that_request_last()
for cleanup.

complete_request() was introduced by earlier part of this patch-set,
not to break the existing users of end_that_request_last().

Since all users are converted to blk_end_request interfaces and
end_that_request_last() is no longer exported, the code can be
merged to end_that_request_last().

Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:37:15 +01:00
Kiyoshi Ueda
5450d3e1d6 blk_end_request: cleanup 'uptodate' related code (take 4)
This patch converts 'uptodate' arguments of no longer exported
interfaces, end_that_request_first/last, to 'error', and removes
internal conversions for it in blk_end_request interfaces.

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

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

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

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

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

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

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

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

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

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

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

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:37:04 +01:00
Kiyoshi Ueda
9e6e39f2c4 blk_end_request: changing block layer core (take 4)
This patch converts core parts of block layer to use blk_end_request
interfaces.  Related 'uptodate' arguments are converted to 'error'.

'dequeue' argument was originally introduced for end_dequeued_request(),
where no attempt should be made to dequeue the request as it's already
dequeued.
However, it's not necessary as it can be checked with
list_empty(&rq->queuelist).
(Dequeued request has empty list and queued request doesn't.)
And it has been done in blk_end_request interfaces.

As a result of this patch, end_queued_request() and
end_dequeued_request() become identical.  A future patch will merge
and rename them and change users of those functions.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:35:57 +01:00
Kiyoshi Ueda
3b11313a6c blk_end_request: add/export functions to get request size (take 4)
This patch adds/exports functions to get the size of request in bytes.
They are useful because blk_end_request interfaces take bytes
as a completed I/O size instead of sectors.

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

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

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

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

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

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

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

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:35:53 +01:00
Christof Schmitt
6da127ad09 blktrace: Add blktrace ioctls to SCSI generic devices
Since the SCSI layer uses the request queues from the block layer, blktrace can
also be used to trace the requests to all SCSI devices (like SCSI tape drives),
not only disks. The only missing part is the ioctl interface to start and stop
tracing.

This patch adds the SETUP, START, STOP and TEARDOWN ioctls from blktrace to the
sg device files. With this change, blktrace can be used for SCSI devices like
for disks, e.g.: blktrace -d /dev/sg1 -o - | blkparse -i -

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:04:46 +01:00
Linus Torvalds
9b73e76f3c Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (200 commits)
  [SCSI] usbstorage: use last_sector_bug flag universally
  [SCSI] libsas: abstract STP task status into a function
  [SCSI] ultrastor: clean up inline asm warnings
  [SCSI] aic7xxx: fix firmware build
  [SCSI] aacraid: fib context lock for management ioctls
  [SCSI] ch: remove forward declarations
  [SCSI] ch: fix device minor number management bug
  [SCSI] ch: handle class_device_create failure properly
  [SCSI] NCR5380: fix section mismatch
  [SCSI] sg: fix /proc/scsi/sg/devices when no SCSI devices
  [SCSI] IB/iSER: add logical unit reset support
  [SCSI] don't use __GFP_DMA for sense buffers if not required
  [SCSI] use dynamically allocated sense buffer
  [SCSI] scsi.h: add macro for enclosure bit of inquiry data
  [SCSI] sd: add fix for devices with last sector access problems
  [SCSI] fix pcmcia compile problem
  [SCSI] aacraid: add Voodoo Lite class of cards.
  [SCSI] aacraid: add new driver features flags
  [SCSI] qla2xxx: Update version number to 8.02.00-k7.
  [SCSI] qla2xxx: Issue correct MBC_INITIALIZE_FIRMWARE command.
  ...
2008-01-25 17:19:08 -08:00
Greg Kroah-Hartman
f9cb074bff Kobject: rename kobject_init_ng() to kobject_init()
Now that the old kobject_init() function is gone, rename
kobject_init_ng() to kobject_init() to clean up the namespace.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:38 -08:00
Greg Kroah-Hartman
b2d6db5878 Kobject: rename kobject_add_ng() to kobject_add()
Now that the old kobject_add() function is gone, rename kobject_add_ng()
to kobject_add() to clean up the namespace.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:38 -08:00