FUJITA Tomonori [Thu, 28 Aug 2008 06:05:58 +0000 (15:05 +0900)]
block: add blk_rq_aligned helper function
This adds blk_rq_aligned helper function to see if alignment and
padding requirement is satisfied for DMA transfer. This also converts
blk_rq_map_kern and __blk_rq_map_user to use the helper function.
FUJITA Tomonori [Fri, 29 Aug 2008 10:32:18 +0000 (12:32 +0200)]
sg: convert the indirect IO path to use the block layer
This patch converts the indirect IO path (including mmap IO and old
struct sg_header) to use the block layer functions (blk_get_request,
blk_execute_rq_nowait, blk_rq_map_user, etc) instead of
scsi_execute_async().
[Jens: fixed compile error with SCSI logging enabled]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Douglas Gilbert <dougg@torque.net> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
FUJITA Tomonori [Thu, 28 Aug 2008 07:17:08 +0000 (16:17 +0900)]
sg: convert the direct IO path to use the block layer
This patch converts the direct IO path (SG_FLAG_DIRECT_IO) to use the
block layer functions (blk_get_request, blk_execute_rq_nowait,
blk_rq_map_user, etc) instead of scsi_execute_async().
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Douglas Gilbert <dougg@torque.net> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
FUJITA Tomonori [Thu, 28 Aug 2008 07:17:07 +0000 (16:17 +0900)]
sg: convert the non-data path to use the block layer
This patch converts the non data path to use the block layer functions
(blk_get_request, blk_execute_rq_nowait, etc) instead of uses
scsi_execute_async().
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Douglas Gilbert <dougg@torque.net> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
FUJITA Tomonori [Thu, 28 Aug 2008 07:17:06 +0000 (16:17 +0900)]
block: introduce struct rq_map_data to use reserved pages
This patch introduces struct rq_map_data to enable bio_copy_use_iov()
use reserved pages.
Currently, bio_copy_user_iov allocates bounce pages but
drivers/scsi/sg.c wants to allocate pages by itself and use
them. struct rq_map_data can be used to pass allocated pages to
bio_copy_user_iov.
The current users of bio_copy_user_iov simply passes NULL (they don't
want to use pre-allocated pages).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Douglas Gilbert <dougg@torque.net> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Aaron Carroll [Tue, 26 Aug 2008 13:52:36 +0000 (15:52 +0200)]
cfq-iosched: fix queue depth detection
CFQ's detection of queueing devices assumes a non-queuing device and detects
if the queue depth reaches a certain threshold. Under some workloads (e.g.
synchronous reads), CFQ effectively forces a unit queue depth, thus defeating
the detection logic. This leads to poor performance on queuing hardware,
since the idle window remains enabled.
This patch inverts the sense of the logic: assume a queuing-capable device,
and detect if the depth does not exceed the threshold.
Jens Axboe [Tue, 26 Aug 2008 11:34:34 +0000 (13:34 +0200)]
block: don't use bio_has_data() in the completion path
We should just check for rq->bio, as that is really the information
we are looking for. Even if the bio attached doesn't carry data,
we still need to do IO post processing on it.
Jens Axboe [Tue, 26 Aug 2008 08:25:02 +0000 (10:25 +0200)]
block: inherit CPU completion on bio->rq and rq->rq merges
Somewhat incomplete, as we do allow merges of requests and bios
that have different completion CPUs given. This is done on the
assumption that a larger IO is still more beneficial than CPU
locality.
This patch adds support for controlling the IO completion CPU of
either all requests on a queue, or on a per-request basis. We export
a sysfs variable (rq_affinity) which, if set, migrates completions
of requests to the CPU that originally submitted it. A bio helper
(bio_set_completion_cpu()) is also added, so that queuers can ask
for completion on that specific CPU.
In testing, this has been show to cut the system time by as much
as 20-40% on synthetic workloads where CPU affinity is desired.
This requires a little help from the architecture, so it'll only
work as designed for archs that are using the new generic smp
helper infrastructure.
Tejun Heo [Mon, 25 Aug 2008 10:56:17 +0000 (19:56 +0900)]
block: allow disk to have extended device number
Now that disk and partition handlings are mostly unified, it's easy to
allow disk to have extended device number. This patch makes
add_disk() use extended device number if disk->minors is zero. Both
sd and ide-disk are updated to use this.
* sd_format_disk_name() is implemented which can generically determine
the drive name. This removes disk number restriction stemming from
limited device names.
* If sd index goes over SD_MAX_DISKS (which can be increased now BTW),
sd simply doesn't initialize minors letting block layer choose
extended device number.
* If CONFIG_DEBUG_EXT_DEVT is set, both sd and ide-disk always set
minors to 0 and use extended device numbers.
Tejun Heo [Mon, 25 Aug 2008 10:56:16 +0000 (19:56 +0900)]
block: replace @ext_minors with GENHD_FL_EXT_DEVT
With previous changes, it's meaningless to limit the number of
partitions. Replace @ext_minors with GENHD_FL_EXT_DEVT such that
setting the flag allows the disk to have maximum number of allowed
partitions (only limited by the number of entries in parsed_partitions
as determined by MAX_PART constant).
This kills not-too-pretty alloc_disk_ext[_node]() functions and makes
@minors parameter to alloc_disk[_node]() unnecessary. The parameter
is left alone to avoid disturbing the users.
Tejun Heo [Mon, 25 Aug 2008 10:56:15 +0000 (19:56 +0900)]
block: make partition array dynamic
disk->__part used to be statically allocated to the maximum possible
number of partitions. This patch makes partition array allocation
dynamic. The added overhead is minimal as only real change is one
memory dereference changed to RCU one. This saves both a bit of
memory and cpu cycles iterating through unoccupied slots and makes
increasing partition limit easier.
Tejun Heo [Mon, 25 Aug 2008 10:56:14 +0000 (19:56 +0900)]
block: move stats from disk to part0
Move stats related fields - stamp, in_flight, dkstats - from disk to
part0 and unify stat handling such that...
* part_stat_*() now updates part0 together if the specified partition
is not part0. ie. part_stat_*() are now essentially all_stat_*().
* {disk|all}_stat_*() are gone.
* part_round_stats() is updated similary. It handles part0 stats
automatically and disk_round_stats() is killed.
* part_{inc|dec}_in_fligh() is implemented which automatically updates
part0 stats for parts other than part0.
* disk_map_sector_rcu() is updated to return part0 if no part matches.
Combined with the above changes, this makes NULL special case
handling in callers unnecessary.
* Separate stats show code paths for disk are collapsed into part
stats show code paths.
* Rename disk_stat_lock/unlock() to part_stat_lock/unlock()
While at it, reposition stat handling macros a bit and add missing
parentheses around macro parameters.
Tejun Heo [Mon, 25 Aug 2008 10:56:12 +0000 (19:56 +0900)]
block: always set bdev->bd_part
Till now, bdev->bd_part is set only if the bdev was for parts other
than part0. This patch makes bdev->bd_part always set so that code
paths don't have to differenciate common handling.
Tejun Heo [Mon, 25 Aug 2008 10:56:11 +0000 (19:56 +0900)]
block: move holder_dir from disk to part0
Move disk->holder_dir to part0->holder_dir. Kill now mostly
superflous bdev_get_holder().
While at it, kill superflous kobject_get/put() around holder_dir,
slave_dir and cmd_filter creation and collapse
disk_sysfs_add_subdirs() into register_disk(). These serve no purpose
but obfuscating the code.
Tejun Heo [Fri, 29 Aug 2008 07:01:47 +0000 (09:01 +0200)]
block: move __dev from disk to part0
Move disk->__dev to part0->__dev. This simplifies bdget_disk() and
lookup_devt() and allows common sysfs attributes to be unified.
part_to_disk() is updated to handle part0 -> disk.
Updated to include a fix from Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>,
he writes:
"part0 is a "special" partition and doesn't need to have capacity set - this
fixes regression caused by "block: move __dev from disk to part0" commit."
Tejun Heo [Mon, 25 Aug 2008 10:56:07 +0000 (19:56 +0900)]
block: move capacity from disk to part0
Move disk->capacity to part0->nr_sects and convert all users who
directly accessed the field to use {get|set}_capacity(). This is done
early to allow the __dev field to be moved.
genhd and partition code handled disk and partitions separately. All
information about the whole disk was in struct genhd and partitions in
struct hd_struct. However, the whole disk (part0) and other
partitions have a lot in common and the data structures end up having
good number of common fields and thus separate code paths doing the
same thing. Also, the partition array was indexed by partno - 1 which
gets pretty confusing at times.
This patch introduces partition 0 and makes the partition array
indexed by partno. Following patches will unify the handling of disk
and parts piece-by-piece.
This patch also implements disk_partitionable() which tests whether a
disk is partitionable. With coming dynamic partition array change,
the most common usage of disk_max_parts() will be testing whether a
disk is partitionable and the number of max partitions will become
much less important.
Tejun Heo [Mon, 25 Aug 2008 10:56:05 +0000 (19:56 +0900)]
block: implement and use {disk|part}_to_dev()
Implement {disk|part}_to_dev() and use them to access generic device
instead of directly dereferencing {disk|part}->dev. To make sure no
user is left behind, rename generic devices fields to __dev.
This is in preparation of unifying partition 0 handling with other
partitions.
Tejun Heo [Mon, 25 Aug 2008 10:47:25 +0000 (19:47 +0900)]
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.
Tejun Heo [Mon, 25 Aug 2008 10:47:24 +0000 (19:47 +0900)]
sd/ide-disk: apply extended minors to sd and ide
Update sd and ide-disk such that they can take advantage of extended
minors.
ide-disk already has 64 minors per device and currently doesn't use
extended minors although after this patch it can be turned on by
simply tweaking constants.
sd only had 16 minors per device causing problems on certain peculiar
configurations. This patch lifts the restriction and enables it to
use upto 64 minors.
Tejun Heo [Mon, 25 Aug 2008 10:47:23 +0000 (19:47 +0900)]
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.
Tejun Heo [Mon, 25 Aug 2008 10:47:22 +0000 (19:47 +0900)]
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.
Tejun Heo [Mon, 25 Aug 2008 10:47:21 +0000 (19:47 +0900)]
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.
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.
* 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.
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.
Tejun Heo [Mon, 25 Aug 2008 10:30:16 +0000 (19:30 +0900)]
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.
Tejun Heo [Mon, 25 Aug 2008 10:30:15 +0000 (19:30 +0900)]
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.
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.
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.
Tejun Heo [Mon, 25 Aug 2008 10:30:12 +0000 (19:30 +0900)]
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.
Tejun Heo [Mon, 25 Aug 2008 17:50:19 +0000 (19:50 +0200)]
driver-core: use klist for class device list and implement iterator
Iterating over entries using callback usually isn't too fun especially
when the entry being iterated over can't be manipulated freely. This
patch converts class->p->class_devices to klist and implements class
device iterator so that the users can freely build their own control
structure. The users are also free to call back into class code
without worrying about locking.
class_for_each_device() and class_find_device() are converted to use
the new iterators, so their users don't have to worry about locking
anymore either.
Note: This depends on klist-dont-iterate-over-deleted-entries patch
because class_intf->add/remove_dev() depends on proper synchronization
with device removal.
Tejun Heo [Mon, 25 Aug 2008 17:50:16 +0000 (19:50 +0200)]
klist: don't iterate over deleted entries
A klist entry is kept on the list till all its current iterations are
finished; however, a new iteration after deletion also iterates over
deleted entries as long as their reference count stays above zero.
This causes problems for cases where there are users which iterate
over the list while synchronized against list manipulations and
natuarally expect already deleted entries to not show up during
iteration.
This patch implements dead flag which gets set on deletion so that
iteration can skip already deleted entries. The dead flag piggy backs
on the lowest bit of knode->n_klist and only visible to klist
implementation proper.
While at it, drop klist_iter->i_head as it's redundant and doesn't
offer anything in semantics or performance wise as klist_iter->i_klist
is dereferenced on every iteration anyway.
Randy Dunlap [Tue, 19 Aug 2008 18:13:11 +0000 (20:13 +0200)]
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>
Aaron Carroll [Thu, 14 Aug 2008 08:17:14 +0000 (18:17 +1000)]
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.
Aaron Carroll [Thu, 14 Aug 2008 08:17:13 +0000 (18:17 +1000)]
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.
virtio_blk: use a wrapper function to access io context information of IO requests
struct request has an ioprio member but it is never updated because
currently bios do not hold io context information. The implication of
this is that virtio_blk ends up passing useless information to the
backend driver.
That said, some IO schedulers such as CFQ do store io context
information in struct request, but use private members for that, which
means that that information cannot be directly accessed in a IO
scheduler-independent way.
This patch adds a function to obtain the ioprio of a request. We should
avoid accessing ioprio directly and use this function instead, so that
its users do not have to care about future changes in block layer
structures or what the currently active IO controller is.
This patch does not introduce any functional changes but paves the way
for future clean-ups and enhancements.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
David Woodhouse [Sat, 9 Aug 2008 15:42:20 +0000 (16:42 +0100)]
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>
David Woodhouse [Mon, 11 Aug 2008 14:58:42 +0000 (15:58 +0100)]
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>
David Woodhouse [Sun, 10 Aug 2008 11:33:00 +0000 (12:33 +0100)]
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>
David Woodhouse [Tue, 5 Aug 2008 17:08:56 +0000 (18:08 +0100)]
Support 'discard sectors' operation.
We can benefit from knowing that the file system no longer cares about
the contents of certain sectors, by throwing them away immediately and
then never having to garbage collect them, and using the extra free
space to make our operations more efficient. Do so.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
David Woodhouse [Tue, 5 Aug 2008 17:01:53 +0000 (18:01 +0100)]
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>
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.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
tcp: Fix tcp_hybla zero congestion window growth with small rho and large cwnd.
net: Fix netdev_run_todo dead-lock
tcp: Fix possible double-ack w/ user dma
net: only invoke dev->change_rx_flags when device is UP
netrom: Fix sock_orphan() use in nr_release
ax25: Quick fix for making sure unaccepted sockets get destroyed.
Revert "ax25: Fix std timer socket destroy handling."
[Bluetooth] Add reset quirk for A-Link BlueUSB21 dongle
[Bluetooth] Add reset quirk for new Targus and Belkin dongles
[Bluetooth] Fix double frees on error paths of btusb and bpa10x drivers
tcp: Fix tcp_hybla zero congestion window growth with small rho and large cwnd.
Because of rounding, in certain conditions, i.e. when in congestion
avoidance state rho is smaller than 1/128 of the current cwnd, TCP
Hybla congestion control starves and the cwnd is kept constant
forever.
This patch forces an increment by one segment after #send_cwnd calls
without increments(newreno behavior).
Signed-off-by: Daniele Lacamera <root@danielinux.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Herbert Xu [Tue, 7 Oct 2008 22:50:03 +0000 (15:50 -0700)]
net: Fix netdev_run_todo dead-lock
Benjamin Thery tracked down a bug that explains many instances
of the error
unregister_netdevice: waiting for %s to become free. Usage count = %d
It turns out that netdev_run_todo can dead-lock with itself if
a second instance of it is run in a thread that will then free
a reference to the device waited on by the first instance.
The problem is really quite silly. We were trying to create
parallelism where none was required. As netdev_run_todo always
follows a RTNL section, and that todo tasks can only be added
with the RTNL held, by definition you should only need to wait
for the very ones that you've added and be done with it.
There is no need for a second mutex or spinlock.
This is exactly what the following patch does.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Ali Saidi [Tue, 7 Oct 2008 22:31:19 +0000 (15:31 -0700)]
tcp: Fix possible double-ack w/ user dma
From: Ali Saidi <saidi@engin.umich.edu>
When TCP receive copy offload is enabled it's possible that
tcp_rcv_established() will cause two acks to be sent for a single
packet. In the case that a tcp_dma_early_copy() is successful,
copied_early is set to true which causes tcp_cleanup_rbuf() to be
called early which can send an ack. Further along in
tcp_rcv_established(), __tcp_ack_snd_check() is called and will
schedule a delayed ACK. If no packets are processed before the delayed
ack timer expires the packet will be acked twice.
Signed-off-by: David S. Miller <davem@davemloft.net>
Patrick McHardy [Tue, 7 Oct 2008 22:26:48 +0000 (15:26 -0700)]
net: only invoke dev->change_rx_flags when device is UP
Jesper Dangaard Brouer <hawk@comx.dk> reported a bug when setting a VLAN
device down that is in promiscous mode:
When the VLAN device is set down, the promiscous count on the real
device is decremented by one by vlan_dev_stop(). When removing the
promiscous flag from the VLAN device afterwards, the promiscous
count on the real device is decremented a second time by the
vlan_change_rx_flags() callback.
The root cause for this is that the ->change_rx_flags() callback is
invoked while the device is down. The synchronization is meant to mirror
the behaviour of the ->set_rx_mode callbacks, meaning the ->open function
is responsible for doing a full sync on open, the ->close() function is
responsible for doing full cleanup on ->stop() and ->change_rx_flags()
is meant to do incremental changes while the device is UP.
Only invoke ->change_rx_flags() while the device is UP to provide the
intended behaviour.
Tested-by: Jesper Dangaard Brouer <jdb@comx.dk> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Matt Mackall [Tue, 7 Oct 2008 16:37:35 +0000 (11:37 -0500)]
SLOB: fix bogus ksize calculation
SLOB's ksize calculation was braindamaged and generally harmlessly
underreported the allocation size. But for very small buffers, it could
in fact overreport them, leading code depending on krealloc to overrun
the allocation and trample other data.
Signed-off-by: Matt Mackall <mpm@selenic.com> Tested-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Theodore Ts'o (tytso@mit.edu) wrote:
>
> I've been playing with adding some markers into ext4 to see if they
> could be useful in solving some problems along with Systemtap. It
> appears, though, that as of 2.6.27-rc8, markers defined in code which is
> compiled directly into the kernel (i.e., not as modules) don't show up
> in Module.markers:
>
> kvm_trace_entryexit arch/x86/kvm/kvm-intel %u %p %u %u %u %u %u %u
> kvm_trace_handler arch/x86/kvm/kvm-intel %u %p %u %u %u %u %u %u
> kvm_trace_entryexit arch/x86/kvm/kvm-amd %u %p %u %u %u %u %u %u
> kvm_trace_handler arch/x86/kvm/kvm-amd %u %p %u %u %u %u %u %u
>
> (Note the lack of any of the kernel_sched_* markers, and the markers I
> added for ext4_* and jbd2_* are missing as wel.)
>
> Systemtap apparently depends on in-kernel trace_mark being recorded in
> Module.markers, and apparently it's been claimed that it used to be
> there. Is this a bug in systemtap, or in how Module.markers is getting
> built? And is there a file that contains the equivalent information
> for markers located in non-modules code?
Linus Torvalds [Mon, 6 Oct 2008 21:29:16 +0000 (14:29 -0700)]
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: gart iommu have direct mapping when agp is present too
* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6:
ide: workaround for bogus gcc warning in ide_sysfs_register_port()
ide-cd: Optiarc DVD RW AD-7200A does play audio
IDE: Fix platform device registration in Swarm IDE driver (v2)
ide-dma: fix ide_build_dmatable() for TRM290
ide-cd: temporary tray close fix
Linus Torvalds [Mon, 6 Oct 2008 21:27:39 +0000 (14:27 -0700)]
Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] IP27: Fix build errors if CONFIG_MAPPED_KERNEL=y
[MIPS] Fix CMP Kconfig configuration and mark as broken.
Linus Torvalds [Mon, 6 Oct 2008 21:27:15 +0000 (14:27 -0700)]
Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb: (33 commits)
V4L/DVB (9103): em28xx: HVR-900 B3C0 - fix audio clicking issue
V4L/DVB (9099): em28xx: Add detection for K-WORLD DVB-T 310U
V4L/DVB (9092): gspca: Bad init values for sonixj ov7660.
V4L/DVB (9080): gspca: Add a delay after writing to the sonixj sensors.
V4L/DVB (9075): gspca: Bad check of returned status in i2c_read() spca561.
V4L/DVB (9053): fix buffer overflow in uvc-video
V4L/DVB (9043): S5H1420: Fix size of shadow-array to avoid overflow
V4L/DVB (9037): Fix support for Hauppauge Nova-S SE
V4L/DVB (9029): Fix deadlock in demux code
V4L/DVB (8979): sms1xxx: Add new USB product ID for Hauppauge WinTV MiniStick
V4L/DVB (8978): sms1xxx: fix product name for Hauppauge WinTV MiniStick
V4L/DVB (8967): Use correct XC3028L firmware for AMD ATI TV Wonder 600
V4L/DVB (8963): s2255drv field count fix
V4L/DVB (8961): zr36067: Fix RGBR pixel format
V4L/DVB (8960): drivers/media/video/cafe_ccic.c needs mm.h
V4L/DVB (8958): zr36067: Return proper bytes-per-line value
V4L/DVB (8957): zr36067: Restore the default pixel format
V4L/DVB (8955): bttv: Prevent NULL pointer dereference in radio_open
V4L/DVB (8935): em28xx-cards: Remove duplicate entry (EM2800_BOARD_KWORLD_USB2800)
V4L/DVB (8933): gspca: Disable light frquency for zc3xx cs2102 Kokom.
...
atmel-mci: Initialize BLKR before sending data transfer command
The atmel-mci driver sometimes fails data transfers like this:
mmcblk0: error -5 transferring data
end_request: I/O error, dev mmcblk0, sector 2749769
end_request: I/O error, dev mmcblk0, sector 2749777
It turns out that this might be caused by the BLKR register (which
contains the block size and the number of blocks being transfered) being
initialized too late. This patch moves the initialization of BLKR so
that it contains the correct value before the block transfer command is
sent.
This error is difficult to reproduce, but if you insert a long delay
(mdelay(10) or thereabouts) between the calls to atmci_start_command()
and atmci_submit_data(), all transfers seem to fail without this patch,
while I haven't seen any failures with this patch.
Jarek Poplawski [Mon, 6 Oct 2008 19:54:57 +0000 (12:54 -0700)]
netrom: Fix sock_orphan() use in nr_release
While debugging another bug it was found that NetRom socks
are sometimes seen unorphaned in sk_free(). This patch moves
sock_orphan() in nr_release() to the beginning (like in ax25,
or rose).
Reported-and-tested-by: Bernard Pidoux f6bvp <f6bvp@free.fr> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Mon, 6 Oct 2008 19:53:50 +0000 (12:53 -0700)]
ax25: Quick fix for making sure unaccepted sockets get destroyed.
Since we reverted 30902dc3cb0ea1cfc7ac2b17bcf478ff98420d74 ("ax25: Fix
std timer socket destroy handling.") we have to put some kind of fix
in to cure the issue whereby unaccepted connections do not get destroyed.
The approach used here is from Tihomir Heidelberg - 9a4gl
Signed-off-by: David S. Miller <davem@davemloft.net>
Jason Wessel [Mon, 6 Oct 2008 18:50:59 +0000 (13:50 -0500)]
kgdb: call touch_softlockup_watchdog on resume
The softlockup watchdog needs to be touched when resuming the from the
kgdb stopped state to avoid the printk that a CPU is stuck if the
debugger was active for longer than the softlockup threshold.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Jan Kiszka [Mon, 6 Oct 2008 18:50:59 +0000 (13:50 -0500)]
kgdb, x86: Avoid invoking kgdb_nmicallback twice per NMI
Stress-testing KVM's latest NMI support with kgdbts inside an SMP guest,
I came across spurious unhandled NMIs while running the singlestep test.
Looking closer at the code path each NMI takes when KGDB is enabled, I
noticed that kgdb_nmicallback is called twice per event: One time via
DIE_NMI_IPI notification, the second time on DIE_NMI. Removing the first
invocation cures the unhandled NMIs here.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
x86 ACPI: Blacklist two HP machines with buggy BIOSes
There is a bug in the BIOSes of some HP boxes with AMD Turions which
connects IO-APIC pins with ACPI thermal trip points in such a way that
if the state of the IO-APIC is not as expected by the (buggy) BIOS, the
thermal trip points are set to insanely low values (usually all of them
become 16 degrees Celsius). As a result, thermal throttling kicks in
and knock the system down to its shoes.
Unfortunately some of the recent IO-APIC changes made the bug show up.
To prevent this from happening, blacklist machines that are known to be
affected (nx6115 and 6715b in this particular case).
This fixes http://bugzilla.kernel.org/show_bug.cgi?id=11516 listed as
a regression from 2.6.26.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
and the whole story is described in this (huge) thread:
As far as the Dmitry's and Jason's boxes are concerned, I recognized the
symptoms and asked them to verify that the blacklisting helped.
It appears that the buggy BIOS code has been copy-pasted to the entire
range of machines, for no good reason.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Tested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Tested-by: Jason Vas Dias <jason.vas.dias@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marcel Holtmann [Mon, 6 Oct 2008 10:22:52 +0000 (12:22 +0200)]
[Bluetooth] Add reset quirk for A-Link BlueUSB21 dongle
The new A-Link Bluetooth dongle is another one based on the BCM2046 chip
from Broadcom and it also needs to send HCI_Reset before it becomes fully
operational. Without the quirk it will show a lot of I/O errors.
Marcel Holtmann [Mon, 6 Oct 2008 10:22:51 +0000 (12:22 +0200)]
[Bluetooth] Add reset quirk for new Targus and Belkin dongles
Targus and Belkin have come out with new Bluetooth 2.1 capable dongles
using the latest BCM2046 chip from Broadcom. Both of them are so called
HID proxy dongles and they need to send HCI_Reset before they become
fully operational.
Marcel Holtmann [Mon, 6 Oct 2008 10:22:51 +0000 (12:22 +0200)]
[Bluetooth] Fix double frees on error paths of btusb and bpa10x drivers
The transfer buffer of an URB will be automatically freed when using
the URB_FREE_BUFFER transfer_flag. So the extra calls to kfree() will
cause a double free.
projects / linux-2.6-omap-h63xx.git / log