ext4: fix fio regression

We (Linux Kernel Performance project) found a regression introduced
by commit:

  f7fec032aa ext4: track all extent status in extent status tree

The commit causes about 20% performance decrease in fio random write
test. Profiler shows that rb_next() uses a lot of CPU time. The call
stack is:

  rb_next
  ext4_es_find_delayed_extent
  ext4_map_blocks
  _ext4_get_block
  ext4_get_block_write
  __blockdev_direct_IO
  ext4_direct_IO
  generic_file_direct_write
  __generic_file_aio_write
  ext4_file_write
  aio_rw_vect_retry
  aio_run_iocb
  do_io_submit
  sys_io_submit
  system_call_fastpath
  io_submit
  td_io_getevents
  io_u_queued_complete
  thread_main
  main
  __libc_start_main

The cause is that ext4_es_find_delayed_extent() doesn't have an
upper bound, it keeps searching until a delayed extent is found.
When there are a lots of non-delayed entries in the extent state
tree, ext4_es_find_delayed_extent() may uses a lot of CPU time.

Reported-by: LKP project <lkp@linux.intel.com>
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
ath9k: fix key allocation error handling for powersave keys

If no keycache slots are available, ath_key_config can return -ENOSPC.
If the key index is not checked for errors, it can lead to logspam that
looks like this: "ath: wiphy0: keyreset: keycache entry 228 out of range"
This can cause follow-up errors if the invalid keycache index gets
used for tx.

Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ath5k: do not reschedule tx_complete_work on stop

This patch claim to fix "WARNING: at net/mac80211/util.c:599
ieee80211_can_queue_work.isra.7+0x30/0x40", which was reported at:

https://bugzilla.redhat.com/show_bug.cgi?id=922295

We use ATH_STAT_STARTED flag to disallow to perform
ath5k_tx_complete_poll_work() code, hence reschedule
ah->tx_complete_work, when we stop device. This flag was defined in
ath5k code, but it was not used.

I didn't get feedback if the fix works, so patch is compile only tested.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ext4: limit group search loop for non-extent files

In the case where we are allocating for a non-extent file,
we must limit the groups we allocate from to those below
2^32 blocks, and ext4_mb_regular_allocator() attempts to
do this initially by putting a cap on ngroups for the
subsequent search loop.

However, the initial target group comes in from the 
allocation context (ac), and it may already be beyond
the artificially limited ngroups.  In this case,
the limit

	if (group == ngroups)
		group = 0;

at the top of the loop is never true, and the loop will
run away.

Catch this case inside the loop and reset the search to
start at group 0.

[sandeen@redhat.com: add commit msg & comments]

Signed-off-by: Lachlan McIlroy <lmcilroy@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
powerpc: Add an in memory udbg console

This patch adds a new udbg early debug console which utilises
statically defined input and output buffers stored within the kernel
BSS. It is primarily designed to assist with bring up of new hardware
which may not have a working console but which has a method of
reading/writing kernel memory.

This version incorporates comments made by Ben H (thanks!).

Changes from v1:
	- Add memory barriers.
	- Ensure updating of read/write positions is atomic.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/powernv: Properly drop characters if console is closed

If the firmware returns an error such as "closed" (or hardware
error), we should drop characters.

Currently we only do that when a firmware compatible with OPAL v2
APIs is detected, in the code that calls opal_console_write_buffer_space(),
which didn't exist with OPAL v1 (or didn't work).

However, when enabling early debug consoles, the flag indicating
that v2 is supported isn't set yet, causing us, in case of errors
or closed console, to spin forever.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
B43: Handle DMA RX descriptor underrun

Add handling of rx descriptor underflow. This fixes a fault that could
happen on slow machines, where data is received faster than the CPU can
handle. In such a case the device will use up all rx descriptors and
refuse to send any more data before confirming that it is ok. This
patch enables necessary interrupt to discover such a situation and will
handle them by dropping everything in the ring buffer.

Reviewed-by: Michael Buesch <m@bues.ch>
Signed-off-by: Thommy Jakobsson <thommyj@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
iwl4965: workaround connection regression on passive channel

Jake reported that since commit 1672c0e31917f49d31d30d79067103432bc20cc7
"mac80211: start auth/assoc timeout on frame status", he is unable to
connect to his AP, which is configured to use passive channel.

After switch to passive channel 4965 firmware drops any TX packet until
it receives beacon. Before commit 1672c0e3 we waited on channel and
retransmit packet after 200ms, that makes we receive beacon on the
meantime and association process succeed. New mac80211 behaviour cause
that any ASSOC frame fail immediately on iwl4965 and we can not
associate.

This patch restore old mac80211 behaviour for iwl4965, by removing
IEEE80211_HW_REPORTS_TX_ACK_STATUS feature. This feature will be
added again to iwl4965 driver, when different, more complex
workaround for this firmware issue, will be added to the driver.

Cc: stable@vger.kernel.org # 3.9
Bisected-by: Jake Edge <jake@lwn.net>
Reported-and-tested-by: Jake Edge <jake@lwn.net>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ath9k: Fix beacon reconfiguration

When a reset or a channel-change happens, for managed mode,
the HW beacon timers have to be programmed after the TSF has
been synchronized. This is handled via the sync flags.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ath9k: Update initvals for AR9565

* Register Modification for xLNA board.
* TX gain table modification for zero calibration.
* AUX chain (LNA2) sensitivity enhancement
* Modify diversity bias default setting in INI.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
mwifiex: clear is_suspended flag when interrupt is received early

When the XO-4 with 8787 wireless is woken up due to wake-on-WLAN
mwifiex is often flooded with "not allowed while suspended" messages
and the interface is unusable.

[  202.171609] int: sdio_ireg = 0x1
[  202.180700] info: mwifiex_process_hs_config: auto cancelling host
               sleep since there is interrupt from the firmware
[  202.201880] event: wakeup device...
[  202.211452] event: hs_deactivated
[  202.514638] info: --- Rx: Data packet ---
[  202.514753] data: 4294957544 BSS(0-0): Data <= kernel
[  202.514825] PREP_CMD: device in suspended state
[  202.514839] data: dequeuing the packet ec7248c0 ec4869c0
[  202.514886] mwifiex_write_data_sync: not allowed while suspended
[  202.514886] host_to_card, write iomem (1) failed: -1
[  202.514917] mwifiex_write_data_sync: not allowed while suspended
[  202.514936] host_to_card, write iomem (2) failed: -1
[  202.514949] mwifiex_write_data_sync: not allowed while suspended
[  202.514965] host_to_card, write iomem (3) failed: -1
[  202.514976] mwifiex_write_data_async failed: 0xFFFFFFFF

This can be readily reproduced when putting the XO-4 in a loop where
it goes to sleep due to inactivity, but then wakes up due to an
incoming ping. The error is hit within an hour or two.

This issue happens when an interrupt comes in early while host sleep
is still activated. Driver handles this case by auto cancelling host
sleep. However is_suspended flag is still set which prevents any cmd
or data from being sent to firmware. Fix it by clearing is_suspended
flag in this path.

Cc: <stable@vger.kernel.org>
Reported-by: Daniel Drake <dsd@laptop.org>
Tested-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
mwifiex: fix memory leak issue when driver unload

After unregister_netdevice() call the request is queued and
reg_state is changed to NETREG_UNREGISTERING.
As we check for NETREG_UNREGISTERED state, free_netdev() never
gets executed causing memory leak.

Initialize "dev->destructor" to free_netdev() to free device
data after unregistration.

Cc: <stable@vger.kernel.org>
Reported-by: Daniel Drake <dsd@laptop.org>
Tested-by: Daniel Drake <dsd@laptop.org>
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>
mwifiex: fix setting of multicast filter

A small bug in this code was causing the ALLMULTI filter to be set
when in fact we were just wanting to program a selective multicast list
to the hardware.

Fix that bug and remove a redundant if condition in the code that
follows.

This fixes wakeup behaviour when multicast WOL is enabled. Previously,
all multicast packets would wake up the system. Now, only those that the
host intended to receive trigger wakeups.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Cc: <stable@vger.kernel.org>
Acked-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
batman-adv: check proto length before accessing proto string buffer

batadv_param_set_ra() strips the trailing '\n' from the supplied
string buffer without checking the length of the buffer first. This
patches avoids random memory access and associated potential
crashes.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: check return value of pskb_trim_rcsum()

Reported-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Acked-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: make DAT drop ARP requests targeting local clients

In the outgoing ARP request snooping routine in DAT, ARP
Request sent by local clients which are supposed to be
replied by other local clients can be silently dropped.

The destination host will reply by itself through the LAN
and therefore there is no need to involve DAT.

Reported-by: Carlos Quijano <carlos@crqgestion.es>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Tested-by: Carlos Quijano <carlos@crqgestion.es>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
batman-adv: reorder clean up routine in order to avoid race conditions

nc_worker accesses the originator table during its periodic
work, but since the originator table is freed before
stopping the worker this leads to a global protection fault.

Fix this by killing the worker (in nc_free) before freeing
the originator table.

Moreover tidy up the entire clean up routine by running all
the subcomponents freeing procedures first and then killing
the TT and the originator tables at the end.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
powerpc/powernv: Improve kexec reliability

We add a machine_shutdown hook that frees the OPAL interrupts
(so they get masked at the source and don't fire while kexec'ing)
and which triggers an IODA reset on all the PCIe host bridges
which will have the effect of blocking all DMAs and subsequent
PCIs interrupts.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc: hard_irq_disable(): Call trace_hardirqs_off after disabling

lockdep.c has this:
        /*
         * So we're supposed to get called after you mask local IRQs,
         * but for some reason the hardware doesn't quite think you did
         * a proper job.
         */
	if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
		return;

Since irqs_disabled() is based on soft_enabled(), that (not just the
hard EE bit) needs to be 0 before we call trace_hardirqs_off.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem