Commit f0ed2ce840 ("[media] uvcvideo: Set error_idx properly for
extended controls API failures") causes user space to behave incorrectly
on one of my test machines (there is no sound under KDE 4.9.4 using
pulseaudio and there is a knotify4 process occupying one of the CPU
cores 100% of the time). Reverting that commit entirely fixes the
problem for me.
However, commit f0ed2ce840 appears to do more than it follows from its
changelog, because the changelog only says about the changes related to
ctrls->error_idx, while the commit additionally changes error codes
returned by various functions in uvc_ctrl.c and uvc_v4l2.c. It turns
out that the changes of the returned error codes confuse the user spce,
so it is sufficient to revert the part of commit f0ed2ce840 not
mentioned in its changelog to fix the problem.
[ 'ENOENT' is not a valid error return from an ioctl to begin with, and
I don't understand how anybody ever even thought it would be. - Linus ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 68136b10 ("ARM: sunxi: Change device tree naming scheme for
sunxi") changed the naming scheme and the compatible strings used in the
device trees related to the sunXi platform, but forgot to change the
compatible string in the DT machine definition.
This prevents the kernel from booting on these boards.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Modesetting seems to work alright, as does graphics (using binary driver
fuc from nve7...).
Lots to be done no doubt, but this'll get an image on the screen for
people.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
CONFIG_HOTPLUG is going away as an option. As result the __dev*
markings will be going away.
Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio)
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio)
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3)
Acked-by: Barry Song <baohua.song@csr.com> (for sirf)
Reviewed-by: Jean Delvare <khali@linux-fr.org>
[wsa: Fixed "foo* bar" flaws while we are here]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Result of DIV_ROUND_CLOSEST is undefined for negative dividends if the divisor
variable type is unsigned. Fix by declaring divisor as signed variable.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>
Fixed integer overflow in function htb_dequeue
Signed-off-by: Stefan Hasko <hasko.stevo@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
CONFIG_HOTPLUG is always enabled now, so remove the unused code that was
trying to be compiled out when this option was disabled, in the
networking core.
Cc: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove some __dev* markings that snuck in the 3.8-rc1 merge window in
the drivers/net/* directory.
Cc: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If an LM73 device does not exist on an I2C bus, attempts to communicate
with the device result in an error code returned from the i2c read/write
functions. The current lm73 driver casts that return value from a s32
type to a s16 type, then converts it to a temperature in celsius.
Because negative temperatures are valid, it is difficult to distinguish
between an error code printed to the response buffer and a negative
temperature recorded by the sensor.
The solution is to evaluate the return value from the i2c functions
before performing any temperature calculations. If the i2c function did
not succeed, the error code should be passed back through the virtual
file system layer instead of being printed into the response buffer.
Before:
$ cat /sys/class/hwmon/hwmon0/device/temp1_input
-46
After:
$ cat /sys/class/hwmon/hwmon0/device/temp1_input
cat: read error: No such device or address
Signed-off-by: Chris Verges <kg4ysn@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Pull watchdog updates from Wim Van Sebroeck:
"This includes some fixes and code improvements (like
clk_prepare_enable and clk_disable_unprepare), conversion from the
omap_wdt and twl4030_wdt drivers to the watchdog framework, addition
of the SB8x0 chipset support and the DA9055 Watchdog driver and some
OF support for the davinci_wdt driver."
* git://www.linux-watchdog.org/linux-watchdog: (22 commits)
watchdog: mei: avoid oops in watchdog unregister code path
watchdog: Orion: Fix possible null-deference in orion_wdt_probe
watchdog: sp5100_tco: Add SB8x0 chipset support
watchdog: davinci_wdt: add OF support
watchdog: da9052: Fix invalid free of devm_ allocated data
watchdog: twl4030_wdt: Change TWL4030_MODULE_PM_RECEIVER to TWL_MODULE_PM_RECEIVER
watchdog: remove depends on CONFIG_EXPERIMENTAL
watchdog: Convert dev_printk(KERN_<LEVEL> to dev_<level>(
watchdog: DA9055 Watchdog driver
watchdog: omap_wdt: eliminate goto
watchdog: omap_wdt: delete redundant platform_set_drvdata() calls
watchdog: omap_wdt: convert to devm_ functions
watchdog: omap_wdt: convert to new watchdog core
watchdog: WatchDog Timer Driver Core: fix comment
watchdog: s3c2410_wdt: use clk_prepare_enable and clk_disable_unprepare
watchdog: imx2_wdt: Select the driver via ARCH_MXC
watchdog: cpu5wdt.c: add missing del_timer call
watchdog: hpwdt.c: Increase version string
watchdog: Convert twl4030_wdt to watchdog core
davinci_wdt: preparation for switch to common clock framework
...
Pull CIFS fixes from Steve French:
"Misc small cifs fixes"
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
cifs: eliminate cifsERROR variable
cifs: don't compare uniqueids in cifs_prime_dcache unless server inode numbers are in use
cifs: fix double-free of "string" in cifs_parse_mount_options
Of particular note:
- Disable broken WRITE SAME support in all targets except linear and striped.
Use it when kcopyd is zeroing blocks.
- Remove several mempools from targets by moving the data into the bio's new
front_pad area(which dm calls 'per_bio_data').
- Fix a race in thin provisioning if discards are misused.
- Prevent userspace from interfering with the ioctl parameters and
use kmalloc for the data buffer if it's small instead of vmalloc.
- Throttle some annoying error messages when I/O fails.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)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=yzhS
-----END PGP SIGNATURE-----
Merge tag 'dm-3.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm
Pull dm update from Alasdair G Kergon:
"Miscellaneous device-mapper fixes, cleanups and performance
improvements.
Of particular note:
- Disable broken WRITE SAME support in all targets except linear and
striped. Use it when kcopyd is zeroing blocks.
- Remove several mempools from targets by moving the data into the
bio's new front_pad area(which dm calls 'per_bio_data').
- Fix a race in thin provisioning if discards are misused.
- Prevent userspace from interfering with the ioctl parameters and
use kmalloc for the data buffer if it's small instead of vmalloc.
- Throttle some annoying error messages when I/O fails."
* tag 'dm-3.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm: (36 commits)
dm stripe: add WRITE SAME support
dm: remove map_info
dm snapshot: do not use map_context
dm thin: dont use map_context
dm raid1: dont use map_context
dm flakey: dont use map_context
dm raid1: rename read_record to bio_record
dm: move target request nr to dm_target_io
dm snapshot: use per_bio_data
dm verity: use per_bio_data
dm raid1: use per_bio_data
dm: introduce per_bio_data
dm kcopyd: add WRITE SAME support to dm_kcopyd_zero
dm linear: add WRITE SAME support
dm: add WRITE SAME support
dm: prepare to support WRITE SAME
dm ioctl: use kmalloc if possible
dm ioctl: remove PF_MEMALLOC
dm persistent data: improve improve space map block alloc failure message
dm thin: use DMERR_LIMIT for errors
...
This reverts commit 79f77bf9a4.
This is obviously wrong, and I have no idea how I missed seeing the
warning in testing: I must just not have looked at the right logs. The
caller bumps rq_resused/rq_next_page, so it will always be hit on a
large enough read.
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- cxgb4 changes to fix lookup engine hash collisions
- mlx4 changes to make flow steering usable
- fix to IPoIB to avoid pinning dst reference for too long
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)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=lDXt
-----END PGP SIGNATURE-----
Merge tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
Pull more infiniband changes from Roland Dreier:
"Second batch of InfiniBand/RDMA changes for 3.8:
- cxgb4 changes to fix lookup engine hash collisions
- mlx4 changes to make flow steering usable
- fix to IPoIB to avoid pinning dst reference for too long"
* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
RDMA/cxgb4: Fix bug for active and passive LE hash collision path
RDMA/cxgb4: Fix LE hash collision bug for passive open connection
RDMA/cxgb4: Fix LE hash collision bug for active open connection
mlx4_core: Allow choosing flow steering mode
mlx4_core: Adjustments to Flow Steering activation logic for SR-IOV
mlx4_core: Fix error flow in the flow steering wrapper
mlx4_core: Add QPN enforcement for flow steering rules set by VFs
cxgb4: Add LE hash collision bug fix path in LLD driver
cxgb4: Add T4 filter support
IPoIB: Call skb_dst_drop() once skb is enqueued for sending
* a set of patches from Lars-Peter Clausen to generalize asm/mmu.h
and use it in the architectures that don't need any special handling.
* A patch from Will Deacon to remove the {read,write}s{b,w,l} as
discussed during the arm64 review
* A patch from James Hogan that helps with the meta architecture
series.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)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=uewR
-----END PGP SIGNATURE-----
Merge tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic cleanup from Arnd Bergmann:
"These are a few cleanups for asm-generic:
- a set of patches from Lars-Peter Clausen to generalize asm/mmu.h
and use it in the architectures that don't need any special
handling.
- A patch from Will Deacon to remove the {read,write}s{b,w,l} as
discussed during the arm64 review
- A patch from James Hogan that helps with the meta architecture
series."
* tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
xtensa: Use generic asm/mmu.h for nommu
h8300: Use generic asm/mmu.h
c6x: Use generic asm/mmu.h
asm-generic/mmu.h: Add support for FDPIC
asm-generic/mmu.h: Remove unused vmlist field from mm_context_t
asm-generic: io: remove {read,write} string functions
asm-generic/io.h: remove asm/cacheflush.h include
Commit db5b0ae007 ("Merge tag 'dt' of git://git.kernel.org/.../arm-soc")
causes a duplicated build target. This patch fixes it and sorts out the
build target alphabetically so that we can recognize something wrong
easily.
Cc: Olof Johansson <olof@lixom.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When netdev_set_master faild in br_add_if, we should
call br_netpoll_disable to do some cleanup jobs,such
as free the memory of struct netpoll which allocated
in br_netpoll_enable.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Acked-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 96442e4242 (tuntap: choose the txq based on rxq)
added a per tun_struct kmem_cache.
As soon as several tun_struct are used, we get an error
because two caches cannot have same name.
Use the default kmalloc()/kfree_rcu(), as it reduce code
size and doesn't have performance impact here.
Reported-by: Paul Moore <pmoore@redhat.com>
Tested-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using a seqlock for devnet_rename_seq is not a good idea,
as device_rename() can sleep.
As we hold RTNL, we dont need a protection for writers,
and only need a seqcount so that readers can catch a change done
by a writer.
Bug added in commit c91f6df2db (sockopt: Change getsockopt() of
SO_BINDTODEVICE to return an interface name)
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Once skb_realloc_headroom() is called, tiph might point to freed memory.
Cache tiph->ttl value before the reallocation, to avoid unexpected
behavior.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipgre_tunnel_xmit() parses network header as IP unconditionally.
But transmitting packets are not always IP packet. For example such packet
can be sent by packet socket with sockaddr_ll.sll_protocol set.
So make the function check if skb->protocol is IP.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a typo here so we do a double lock instead of an unlock.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename stripe_map_discard to stripe_map_range and reuse it for WRITE
SAME bio processing.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch removes map_info from bio-based device mapper targets.
map_info is still used for request-based targets.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Eliminate struct map_info from dm-snap.
map_info->ptr was used in dm-snap to indicate if the bio was tracked.
If map_info->ptr was non-NULL, the bio was linked in tracked_chunk_hash.
This patch removes the use of map_info->ptr. We determine if the bio was
tracked based on hlist_unhashed(&c->node). If hlist_unhashed is true,
the bio is not tracked, if it is false, the bio is tracked.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch removes endio_hook_pool from dm-thin and uses per-bio data instead.
This patch removes any use of map_info in preparation for the next patch
that removes map_info from bio-based device mapper.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Don't use map_info any more in dm-raid1.
map_info was used for writes to hold the region number. For this purpose
we add a new field dm_bio_details to dm_raid1_bio_record.
map_info was used for reads to hold a pointer to dm_raid1_bio_record (if
the pointer was non-NULL, bio details were saved; if the pointer was
NULL, bio details were not saved). We use
dm_raid1_bio_record.details->bi_bdev for this purpose. If bi_bdev is
NULL, details were not saved, if bi_bdev is non-NULL, details were
saved.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Replace map_info with a per-bio structure "struct per_bio_data" in dm-flakey.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Rename struct read_record to bio_record in dm-raid1.
In the following patch, the structure will be used for both read and
write bios, so rename it.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch moves target_request_nr from map_info to dm_target_io and
makes it accessible with dm_bio_get_target_request_nr.
This patch is a preparation for the next patch that removes map_info.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Replace tracked_chunk_pool with per_bio_data in dm-snap.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Replace io_mempool with per_bio_data in dm-verity.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Replace read_record_pool with per_bio_data in dm-raid1.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce a field per_bio_data_size in struct dm_target.
Targets can set this field in the constructor. If a target sets this
field to a non-zero value, "per_bio_data_size" bytes of auxiliary data
are allocated for each bio submitted to the target. These data can be
used for any purpose by the target and help us improve performance by
removing some per-target mempools.
Per-bio data is accessed with dm_per_bio_data. The
argument data_size must be the same as the value per_bio_data_size in
dm_target.
If the target has a pointer to per_bio_data, it can get a pointer to
the bio with dm_bio_from_per_bio_data() function (data_size must be the
same as the value passed to dm_per_bio_data).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add WRITE SAME support to dm-io and make it accessible to
dm_kcopyd_zero(). dm_kcopyd_zero() provides an asynchronous interface
whereas the blkdev_issue_write_same() interface is synchronous.
WRITE SAME is a SCSI command that can be leveraged for more efficient
zeroing of a specified logical extent of a device which supports it.
Only a single zeroed logical block is transfered to the target for each
WRITE SAME and the target then writes that same block across the
specified extent.
The dm thin target uses this.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The linear target can already support WRITE SAME requests so signal
this by setting num_write_same_requests to 1.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
WRITE SAME bios have a payload that contain a single page. When
cloning WRITE SAME bios DM has no need to modify the bi_io_vec
attributes (and doing so would be detrimental). DM need only alter the
start and end of the WRITE SAME bio accordingly.
Rather than duplicate __clone_and_map_discard, factor out a common
function that is also used by __clone_and_map_write_same.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Allow targets to opt in to WRITE SAME support by setting
'num_write_same_requests' in the dm_target structure.
A dm device will only advertise WRITE SAME support if all its
targets and all its underlying devices support it.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If the parameter buffer is small enough, try to allocate it with kmalloc()
rather than vmalloc().
vmalloc is noticeably slower than kmalloc because it has to manipulate
page tables.
In my tests, on PA-RISC this patch speeds up activation 13 times.
On Opteron this patch speeds up activation by 5%.
This patch introduces a new function free_params() to free the
parameters and this uses new flags that record whether or not vmalloc()
was used and whether or not the input buffer must be wiped after use.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When allocating memory for the userspace ioctl data, set some
appropriate GPF flags directly instead of using PF_MEMALLOC.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
