PCI core will initialize device MSI/MSI-X capability in
pci_msi_init_pci_dev(). So device driver should use
pci_dev->msi_cap/msix_cap to determine whether the device
support MSI/MSI-X instead of using
pci_find_capability(pci_dev, PCI_CAP_ID_MSI/MSIX).
Access to PCIe device config space again will consume more time.
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Cc: Andrew Gallatin <gallatin@myri.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
PCI core will initialize device MSI/MSI-X capability in
pci_msi_init_pci_dev(). So device driver should use
pci_dev->msi_cap/msix_cap to determine whether the device
support MSI/MSI-X instead of using
pci_find_capability(pci_dev, PCI_CAP_ID_MSI/MSIX).
Access to PCIe device config space again will consume more time.
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Cc: Eilon Greenstein <eilong@broadcom.com>
Cc: netdev@vger.kernel.org
Acked-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
PCI core will initialize device MSI/MSI-X capability in
pci_msi_init_pci_dev(). So device driver should use
pci_dev->msi_cap/msix_cap to determine whether the device
support MSI/MSI-X instead of using
pci_find_capability(pci_dev, PCI_CAP_ID_MSI/MSIX).
Access to PCIe device config space again will consume more time.
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Cc: Michael Chan <mchan@broadcom.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixed the condition of extend_desc for jumbo frame.
There is no check routine for extend_desc in the stmmac_jumbo_frm function.
Even though extend_desc is set if dma_tx is used instead of dma_etx.
It causes kernel panic.
Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__initdata should be placed between the variable name and equal
sign for the variable to be placed in the intended section.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
__initdata should be placed between the variable name and equal
sign for the variable to be placed in the intended section.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The LNA combining algorithm has to be run for cards
that support the required diversity features, make
sure that that correct conditions are met before
enabing this algorithm.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
BTCOEX has to be *disabled* for WLAN RX diversity to
work on combo cards.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Create a per-vif dummy node entry for keeping the multicast software
queues. This helps in setups with a lot of mulitcast traffic that could
otherwise potentially drown out unicast traffic to stations.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Instead of trying to schedule the same TID multiple times in a loop,
iterate over other TIDs/stations first.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This is a first step for improving fairness between legacy and 802.11n
traffic, and it should also improve reliability of resets and channel
changes by keeping the hardware queue depth very short.
When an aggregation session is torn down, all packets in the retry queue
will be removed from the BAW and freed.
For all subframes that have not been transmitted yet, the A-MPDU flag
will be cleared, and a sequence number allocated. This ensures that the
next A-MPDU session will get the correct initial sequence number.
This happens both on aggregation session start and stop.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Otherwise in some cases, EAPOL frames might be filtered during the
initial handshake, causing delays and assoc failures.
Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When the tid aggregation state has been marked as inactive, free
completed tx packets immediately. When a new aggregation session has not
been initialized yet, the BAW checks do not recognize it as expired.
Might fix potential stalls in setting up a new aggregation session.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
- Allow ath_tx_get_tid_subframe to return non-AMPDU subframes.
- Reset the tid paused state on aggregation stop
- Initialize software queues even when HT is not supported
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When a packet has been tracked as part of the BlockAck window and added
to the hardware queue, it can end up back in the TID queue again with
fi->retries still set to 0 (e.g. if the frame was filtered). Keep an
extra bit for the BAW tracking status to fix this corner case.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The check for ATH_AMPDU_SUBFRAME_DEFAULT is unnecessary, since it's set
to half the maximum BlockAck Window size, which is already the maximum
value that h_baw could possibly have. Also remove unnecessary variables.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Improves packet retry order and helps with further tx queueing
improvements.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This is essentially the same, but written shorter.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
rt2x00queue_pause_queue_nocheck()is used only in this file.
Fix the following sparse warning:
drivers/net/wireless/rt2x00/rt2x00queue.c:939:6: warning: symbol 'rt2x00queue_pause_queue_nocheck' was not declared. Should it be
static?
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Make sure that CONFIG_ATH9K_BTCOEX_SUPPORT is used for
the WLAN/BT RX diversity hooks.
Reported by the kernel build testing backend.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Coalesce filters are configured in firmware based on settings
received from cfg80211.
Packet type which is required by firmware is determined based on
provided patterns in a rule:
Unicast: if pattern '01' with offset 0 is found
Multicast: if pattern '33:33' or '01:00:5e' with offset 0 is found
Broadcast: if pattern 'ff:ff:ff:ff' with offset 0 is found
Some example coalesce configuration files:
1) Coalesce Rx data packets from 192.168.0.88
mac address of our device is 00:50:43:21:53:7A
Source IP address offset comes out as 52 after following
calculations:
32 bytes of HW 802.11 header + 8 bytes LLC +
12 bytes in IPV4 header till source IP address
Destination mac is at offset 6 in HW header.
delay=100
condition=1
patterns=01,6+00:50:43:22,10+53:7A,52+c0:a8:00:58
2) Coalesce all broadcast and multicast packets(Multiple packet
types are not allowed in a single rule. Hence created separate
rules)
delay=400
condition=1
patterns=33:33
delay=400
condition=1
patterns=ff:ff:ff:ff
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The offset number is increased to accomodate requests from
user to match more fields in a Rx packet.
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
It is modified so that it can be reused for coalesce feature.
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Their names were generic. We need to define similar macros
for coalesce feature. Hence they are renamed here.
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Pull HID fix from Jiri Kosina:
"Revert of a patch which breaks enumeration workaround in
hid-logitech-dj"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
Revert "HID: hid-logitech-dj: querying_devices was never set"
- omapdss: compilation fix and DVI fix for PandaBoard
- mxsfb: fix colors when using 18bit LCD bus
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Merge tag 'fbdev-fixes-3.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux
Pull fbdev fixes from Tomi Valkeinen:
- omapdss: compilation fix and DVI fix for PandaBoard
- mxsfb: fix colors when using 18bit LCD bus
* tag 'fbdev-fixes-3.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux:
ARM: OMAP: dss-common: fix Panda's DVI DDC channel
video: mxsfb: fix color settings for 18bit data bus and 32bpp
OMAPDSS: analog-tv-connector: compile fix
Pull drm fixes from Dave Airlie:
"Mostly radeon, more fixes for dynamic power management which is is off
by default for this release anyways, but there are a large number of
testers, so I'd like to keep merging the fixes.
Otherwise, radeon UVD fixes affecting suspend/resume regressions, i915
regression fixes, one for your mac mini, ast, mgag200, cirrus ttm fix
and one regression fix in the core"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (25 commits)
drm: Don't pass negative delta to ktime_sub_ns()
drm/radeon: make missing smc ucode non-fatal
drm/radeon/dpm: require rlc for dpm
drm/radeon/cik: use a mutex to properly lock srbm instanced registers
drm/radeon: remove unnecessary unpin
drm/radeon: add more UVD CS checking
drm/radeon: stop sending invalid UVD destroy msg
drm/radeon: only save UVD bo when we have open handles
drm/radeon: always program the MC on startup
drm/radeon: fix audio dto calculation on DCE3+ (v3)
drm/radeon/dpm: disable sclk ss on rv6xx
drm/radeon: fix halting UVD
drm/radeon/dpm: adjust power state properly for UVD on SI
drm/radeon/dpm: fix spread spectrum setup (v2)
drm/radeon/dpm: adjust thermal protection requirements
drm/radeon: select audio dto based on encoder id for DCE3
drm/radeon: properly handle pm on gpu reset
drm/i915: do not disable backlight on vgaswitcheroo switch off
drm/i915: Don't call encoder's get_config unless encoder is active
drm/i915: avoid brightness overflow when doing scale
...
This is a regression introduced by:
commit fe5c3561e6
Author: stephen hemminger <stephen@networkplumber.org>
Date: Sat Jul 13 10:18:18 2013 -0700
vxlan: add necessary locking on device removal
The problem is that vxlan_dellink(), which is called with RTNL lock
held, tries to flush the workqueue synchronously, but apparently
igmp_join and igmp_leave work need to hold RTNL lock too, therefore we
have a soft lockup!
As suggested by Stephen, probably the flush_workqueue can just be
removed and let the normal refcounting work. The workqueue has a
reference to device and socket, therefore the cleanups should work
correctly.
Suggested-by: Stephen Hemminger <stephen@networkplumber.org>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: David S. Miller <davem@davemloft.net>
Tested-by: Cong Wang <amwang@redhat.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a regression introduced by:
commit 3fc2de2fab
Author: stephen hemminger <stephen@networkplumber.org>
Date: Thu Jul 18 08:40:15 2013 -0700
vxlan: fix igmp races
Before this commit, the old code was:
if (vxlan_group_used(vn, vxlan->default_dst.remote_ip))
ip_mc_join_group(sk, &mreq);
else
ip_mc_leave_group(sk, &mreq);
therefore we shoud check vxlan_group_used(), not its opposite,
for igmp_join.
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename mib counter from "low latency" to "busy poll"
v1 also moved the counter to the ip MIB (suggested by Shawn Bohrer)
Eric Dumazet suggested that the current location is better.
So v2 just renames the counter to fit the new naming convention.
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the restructuring of the lksctp.org site, we only allow bug
reports through the SCTP mailing list linux-sctp@vger.kernel.org,
not via SF, as SF is only used for web hosting and nothing more.
While at it, also remove the obvious statement that bugs will be
fixed and incooperated into the kernel.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Get rid of the last module parameter for SCTP and make this
configurable via sysctl for SCTP like all the rest of SCTP's
configuration knobs.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds the new procfs knobs:
/proc/sys/net/ipv4/conf/*/igmpv2_unsolicited_report_interval
/proc/sys/net/ipv4/conf/*/igmpv3_unsolicited_report_interval
Which will allow userspace configuration of the IGMP unsolicited report
interval (see below) in milliseconds. The defaults are 10000ms for IGMPv2
and 1000ms for IGMPv3 in accordance with RFC2236 and RFC3376.
Background:
If an IGMP join packet is lost you will not receive data sent to the
multicast group so if no data arrives from that multicast group in a
period of time after the IGMP join a second IGMP join will be sent. The
delay between joins is the "IGMP Unsolicited Report Interval".
Prior to this patch this value was hard coded in the kernel to 10s for
IGMPv2 and 1s for IGMPv3. 10s is unsuitable for some use-cases, such as
IPTV as it can cause channel change to be slow in the presence of packet
loss.
This patch allows the value to be overridden from userspace for both
IGMPv2 and IGMPv3 such that it can be tuned accoding to the network.
Tested with Wireshark and a simple program to join a (non-existent)
multicast group. The distribution of timings for the second join differ
based upon setting the procfs knobs.
igmpvX_unsolicited_report_interval is intended to follow the pattern
established by force_igmp_version, and while a procfs entry has been added
a corresponding sysctl knob has not as it is my understanding that sysctl
is deprecated[1].
[1]: http://lwn.net/Articles/247243/
Signed-off-by: William Manley <william.manley@youview.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The procfs knob /proc/sys/net/ipv4/conf/*/force_igmp_version allows the
IGMP protocol version to use to be explicitly set. As a side effect this
caused the routing cache to be flushed as it was declared as a
DEVINET_SYSCTL_FLUSHING_ENTRY. Flushing is unnecessary and this patch
makes it so flushing does not occur.
Requested by Hannes Frederic Sowa as he was reviewing other patches
adding procfs entries.
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: William Manley <william.manley@youview.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If an IGMP join packet is lost you will not receive data sent to the
multicast group so if no data arrives from that multicast group in a
period of time after the IGMP join a second IGMP join will be sent. The
delay between joins is the "IGMP Unsolicited Report Interval".
Previously this value was hard coded to be chosen randomly between 0-10s.
This can be too long for some use-cases, such as IPTV as it can cause
channel change to be slow in the presence of packet loss.
The value 10s has come from IGMPv2 RFC2236, which was reduced to 1s in
IGMPv3 RFC3376. This patch makes the kernel use the 1s value from the
later RFC if we are operating in IGMPv3 mode. IGMPv2 behaviour is
unaffected.
Tested with Wireshark and a simple program to join a (non-existent)
multicast group. The distribution of timings for the second join differ
based upon setting /proc/sys/net/ipv4/conf/eth0/force_igmp_version.
Signed-off-by: William Manley <william.manley@youview.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduced in cf3c4c0306
("8139cp: Add dma_mapping_error checking")
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Same behavior than 802.1q : finds the encapsulated protocol and
skip 32bit header.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix ipgre_header() (header_ops->create) to return the correct
amount of bytes pushed. Most callers of dev_hard_header() seem
to care only if it was success, but af_packet.c uses it as
offset to the skb to copy from userspace only once. In practice
this fixes packet socket sendto()/sendmsg() to gre tunnels.
Regression introduced in c544193214
("GRE: Refactor GRE tunneling code.")
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
device_close()->recalc_sigpending() is not needed, sigprocmask() takes
care of TIF_SIGPENDING correctly.
And without ->siglock it is racy and wrong, it can wrongly clear
TIF_SIGPENDING and miss a signal.
But even with this patch device_close() is still buggy:
1. sigprocmask() should not be used, we have set_task_blocked(),
but this is minor.
2. We should never block SIGKILL or SIGSTOP, and this is what
the code tries to do.
3. This can't protect against SIGKILL or SIGSTOP anyway. Another
thread can do signal_wake_up(), say, do_signal_stop() or
complete_signal() or debugger.
4. sigprocmask(SIG_BLOCK, allsigs) doesn't necessarily clears
TIF_SIGPENDING, say, freezing() or ->jobctl.
5. device_write() looks equally wrong by the same reason.
Looks like, this tries to protect some wait_event_interruptible() logic
from signals, it should be turned into uninterruptible wait. Or we need
to implement something like signals_stop/start for such a use-case.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 407a2c2a4d.
Explanation provided by Benjamin Tissoires:
Commit "HID: hid-logitech-dj, querying_devices was never set" activate
a flag which guarantees that we do not ask the receiver for too many
enumeration. When the flag is set, each following enumeration call is
discarded (the usb request is not forwarded to the receiver). The flag
is then released when the driver receive a pairing information event,
which normally follows the enumeration request.
However, the USB3 bug makes the driver think the enumeration request
has been forwarded to the receiver. However, it is actually not the
case because the USB stack returns -EPIPE. So, when a new unknown
device appears, the workaround consisting in asking for a new
enumeration is not working anymore: this new enumeration is discarded
because of the flag, which is never reset.
A solution could be to trigger a timeout before releasing it, but for
now, let's just revert the patch.
Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Tested-by: Sune Mølgaard <sune@molgaard.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
If a transaction is rolled back, the Target Address Register (TAR), Processor
Priority Register (PPR) and Data Stream Control Register (DSCR) should be
restored to the checkpointed values before the transaction began. Any changes
to these SPRs inside the transaction should not be visible in the abort
handler.
Currently Linux doesn't save or restore the checkpointed TAR, PPR or DSCR. If
we preempt a processes inside a transaction which has modified any of these, on
process restore, that same transaction may be aborted we but we won't see the
checkpointed versions of these SPRs.
This adds checkpointed versions of these SPRs to the thread_struct and adds the
save/restore of these three SPRs to the treclaim/trechkpt code.
Without this if any of these SPRs are modified during a transaction, users may
incorrectly see a speculated SPR value even if the transaction is aborted.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: <stable@vger.kernel.org> [v3.10]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This moves us to save the Target Address Register (TAR) a earlier in
__switch_to. It introduces a new function save_tar() to do this.
We need to save the TAR earlier as we will overwrite it in the transactional
memory reclaim/recheckpoint path. We are going to do this in a subsequent
patch which will fix saving the TAR register when it's modified inside a
transaction.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: <stable@vger.kernel.org> [v3.10]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
POWER8 allows the DSCR to be accessed directly from userspace via a new SPR
number 0x3 (Rather than 0x11. DSCR SPR number 0x11 is still used on POWER8 but
like POWER7, is only accessible in HV and OS modes). Currently, we allow this
by setting H/FSCR DSCR bit on boot.
Unfortunately this doesn't work, as the kernel needs to see the DSCR change so
that it knows to no longer restore the system wide version of DSCR on context
switch (ie. to set thread.dscr_inherit).
This clears the H/FSCR DSCR bit initially. If a process then accesses the DSCR
(via SPR 0x3), it'll trap into the kernel where we set thread.dscr_inherit in
facility_unavailable_exception().
We also change _switch() so that we set or clear the H/FSCR DSCR bit based on
the thread.dscr_inherit.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: <stable@vger.kernel.org> [v3.10]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
