fuse: add FUSE_AUTO_INVAL_DATA init flag

FUSE_AUTO_INVAL_DATA is provided to enable updated/auto cache
invalidation logic.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
fuse: invalidate inode mapping if mtime changes

We currently invalidate the inode address space mapping
if the file size changes unexpectedly. In the case of a
fuse network filesystem, a portion of a file could be
overwritten remotely without changing the file size.
Compare the old mtime as well to detect this condition
and invalidate the mapping if the file has been updated.

The original logic (to ignore changes in mtime) is
preserved unless the client specifies FUSE_AUTO_INVAL_DATA
on init.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
fuse: update attributes on aio_read

A fuse-based network filesystem might allow for the inode
and/or file data to change unexpectedly. A local client
that opens and repeatedly reads a file might never pick
up on such changes and indefinitely return stale data.

Always invoke fuse_update_attributes() in the read path
to cause an attr revalidation when the attributes expire.
This leads to a page cache invalidation if necessary and
ensures fuse issues new read requests to the fuse client.

The original logic (reval only on reads beyond EOF) is
preserved unless the client specifies FUSE_AUTO_INVAL_DATA
on init.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
fuse: add missing INIT flags

Add missing flags that userspace derived from the protocol version number.  This
makes the protocol more flexible.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
fuse: add missing INIT flag descriptions

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
mac80211: fix scan_sdata assignment

We need to use RCU to assign scan_sdata.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
wireless: reg: restore previous behaviour of chan->max_power calculations

commit eccc068e8e84c8fe997115629925e0422a98e4de
Author: Hong Wu <Hong.Wu@dspg.com>
Date:   Wed Jan 11 20:33:39 2012 +0200

    wireless: Save original maximum regulatory transmission power for the calucation of the local maximum transmit pow

changed the way we calculate chan->max_power as min(chan->max_power,
chan->max_reg_power). That broke rt2x00 (and perhaps some other
drivers) that do not set chan->max_power. It is not so easy to fix this
problem correctly in rt2x00.

According to commit eccc068e8 changelog, change claim only to save
maximum regulatory power - changing setting of chan->max_power was side
effect. This patch restore previous calculations of chan->max_power and
do not touch chan->max_reg_power.

Cc: stable@vger.kernel.org # 3.4+
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
vlv: it might be wise if we initialised the flag value...

Otherwise our initial behaviour is "randomly save a bogus PLL
choice" as far as I can see.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
i915: fix error path leak in intel_sdvo_write_cmd

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
i915: Remove silly test

drv_priv->gmbus is an array. Comparing it with NULL is somewhat less useful
than a chocolate teapot.

Possibly we should be testing bus != NULL each iteration of the loop
instead ?

gcc could help by warning too!

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
dma: imx-dma: Fix kernel crash due to missing clock conversion

With the new i.MX clock infrastructure we need to request the dma clocks
seperately: ahb and ipg clocks.

This fixes the following kernel crash and make audio to be functional again:

root@freescale /home$ aplay audio48k16S.wav
Playing WAVE 'audio48k16S.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c7b74000
[00000000] *pgd=a7bb5831, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1] PREEMPT ARM
Modules linked in:
CPU: 0    Not tainted  (3.5.0-rc5-next-20120702-00007-g3028b64 #1128)
PC is at snd_dmaengine_pcm_get_chan+0x8/0x10
LR is at snd_imx_pcm_hw_params+0x18/0xdc
pc : [<c02d3cf8>]    lr : [<c02e95ec>]    psr: a0000013
sp : c7b45e30  ip : ffffffff  fp : c7ae58e0
r10: 00000000  r9 : c7ae981c  r8 : c7b88800
r7 : c7ae5a60  r6 : c7ae5b20  r5 : c7ae9810  r4 : c7afa060
r3 : 00000000  r2 : 00000001  r1 : c7b88800  r0 : c7afa060
Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 0005317f  Table: a7b74000  DAC: 00000015
Process aplay (pid: 701, stack limit = 0xc7b44270)
Stack: (0xc7b45e30 to 0xc7b46000)
5e20:                                     00100000 00000029 c7b88800 c02db870
5e40: c7ae5a60 c02d4594 00000010 01ae5a60 c7ae5a60 c7ae9810 c7ae9810 c7afa060
5e60: c7ae5b20 c7ae5a60 c7b88800 c02e3ef0 c02e3e08 c7b1e400 c7afa060 c7b88800
5e80: 00000000 c0014da8 c7b44000 00000000 bec566ac c02cd400 c7afa060 c7afa060
5ea0: bec56800 c7b88800 c0014da8 c02cdd7c c04ee710 c04ee7b8 00000003 c005fc74
5ec0: 00000000 7fffffff c7b45f00 c7afa060 c7b67420 c7ba3070 00000004 c0014da8
5ee0: c7b44000 00000000 bec566ac c02ced88 c04e95f8 b6f5ab04 c7b45fb0 0145a468
5f00: 0145a600 bec566bc bec56800 c7b67420 c7ba3070 c00d499c c7b45f18 c7b45f18
5f20: 0000001a 00000004 00000001 c7b44000 c0527f40 00000009 00000008 00000000
5f40: c7b44000 c002c9ec 00000001 c04f0ab0 c04ebec0 00000101 00000000 0000000a
5f60: 60000093 c7b67420 bec56800 c25c4111 00000004 c0014da8 c7b44000 00000000
5f80: bec566ac c00d4f38 b6ffb658 00000000 c0522d80 0145a468 b6fd5000 0145a418
5fa0: 00000036 c0014c00 0145a468 b6fd5000 00000004 c25c4111 bec56800 00020001
5fc0: 0145a468 b6fd5000 0145a418 00000036 0145a468 0145a600 bec566bc bec566ac
5fe0: 0145a468 bec56388 b6f65ce4 b6dcebec 20000010 00000004 00000000 00000000
[<c02d3cf8>] (snd_dmaengine_pcm_get_chan+0x8/0x10) from [<c02e95ec>] (snd_imx_pcm_hw_params+0x18/0xdc)
[<c02e95ec>] (snd_imx_pcm_hw_params+0x18/0xdc) from [<c02e3ef0>] (soc_pcm_hw_params+0xe8/0x1f0)
[<c02e3ef0>] (soc_pcm_hw_params+0xe8/0x1f0) from [<c02cd400>] (snd_pcm_hw_params+0x124/0x474)
[<c02cd400>] (snd_pcm_hw_params+0x124/0x474) from [<c02cdd7c>] (snd_pcm_common_ioctl1+0x4b4/0xf74)
[<c02cdd7c>] (snd_pcm_common_ioctl1+0x4b4/0xf74) from [<c02ced88>] (snd_pcm_playback_ioctl1+0x30/0x510)
[<c02ced88>] (snd_pcm_playback_ioctl1+0x30/0x510) from [<c00d499c>] (do_vfs_ioctl+0x80/0x5e4)
[<c00d499c>] (do_vfs_ioctl+0x80/0x5e4) from [<c00d4f38>] (sys_ioctl+0x38/0x60)
[<c00d4f38>] (sys_ioctl+0x38/0x60) from [<c0014c00>] (ret_fast_syscall+0x0/0x2c)
Code: e593000c e12fff1e e59030a0 e59330bc (e5930000)
---[ end trace fa518c8ba3a74e97 ]--

Reported-by: Javier Martin <javier.martin@vista-silicon.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Cc: stable@vger.kernel.org
drm/i915: fix forcewake related hangs on snb

... by adding seemingly redudant posting reads.

This little dragon lair exploded the first time around when we've
refactored the code a bit to use the common wait_for_atomic_us in
"drm/i915: Group the GT routines together in both code and vtable",
which caused QA to file fdo bug #51738.

Chris Wilson entertained a few approaches to fixing #51738: Replacing
the udelay(1) with the previously-used udelay(10) (or any other
"sufficiently larger" delay), adding a posting read, or ditching the
delay completely and using cpu_relax. We went with the cpu_relax and
"915: Workaround hang with BSD and forcewake on SandyBridge". Which
blew up in fdo bug #52424, but adding the posting read while still
using cpu_relax seems to also fix that, it looks like the
posting read is the important ingriedient to fix these rc6 related
hangs on snb.

Popular theories as to why this is like it is include:
- A herd of pink elephants got royally angered somehow.

- The gpu has internally different functional units and judging by the
  register offsets, the forcewake request register and the forcewake
  ack registers are _not_ in the same functional unit (or at least
  aren't reached through the same routes). Hence the posting read
  syncs up with the wrong block and gets the entire gpu confused.

- ...

As a minimal ducttape fix for 3.6, let's just put these posting reads
into place again. We can try fancier approaches (like adding back the
cpu_relax instead of the udelay) in -next.

This (re-)fixes a regression introduced in

commit 990bbdadabaa51828e475eda86ee5720a4910cc3
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Mon Jul 2 11:51:02 2012 -0300

    drm/i915: Group the GT routines together in both code and vtable

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Du Yan <yanx.du@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=52424
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=51738u
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
tcm_vhost: Initial merge for vhost level target fabric driver

This patch adds the initial code for tcm_vhost, a Vhost level TCM
fabric driver for virtio SCSI initiators into KVM guest.

This code is currently up and running on v3.5-rc2 host+guest
from target-pending/for-next-merge.

Using tcm_vhost requires Zhi's -> Stefan -> nab's qemu vhost-scsi tree here:

  http://git.kernel.org/?p=virt/kvm/nab/qemu-kvm.git;a=shortlog;h=refs/heads/vhost-scsi

--

Changelog v4 -> v5:

  Expose ABI version via VHOST_SCSI_GET_ABI_VERSION + use Rev 0 as
  starting point for v3.6-rc code (Stefan + ALiguori + nab)
  Convert vhost_scsi_handle_vq() to vq_err() (nab + MST)
  Minor style fixes from checkpatch (nab)

Changelog v3 -> v4:

  Rename vhost_vring_target -> vhost_scsi_target (mst + nab)
  Use TRANSPORT_IQN_LEN in vhost_scsi_target->vhost_wwpn[] def (nab)
  Move back to drivers/vhost/, and just use drivers/vhost/Kconfig.tcm (mst)
  Move TCM_VHOST related ioctl defines from include/linux/vhost.h ->
  drivers/vhost/tcm_vhost.h as requested by MST (nab)
  Move Kbuild.tcm include from drivers/staging -> drivers/vhost/, and
  just use 'if STAGING' around 'source drivers/vhost/Kbuild.tcm'

Changelog v2 -> v3:

  Unlock on error in tcm_vhost_drop_nexus() (DanC)
  Fix strlen() doesn't count the terminator (DanC)
  Call kfree() on an error path (DanC)
  Convert tcm_vhost_write_pending to use target_execute_cmd (hch + nab)
  Fix another strlen() off by one in tcm_vhost_make_tport (DanC)
  Add option under drivers/staging/Kconfig, and move to drivers/vhost/tcm/
  as requested by MST (nab)

Changelog v1 -> v2:

  Fix tv_cmd completion -> release SGL memory leak (nab)
  Fix sparse warnings for static variable usage ((Fengguang Wu)
  Fix sparse warnings for min() typing + printk format specs (Fengguang Wu)
  Convert to cmwq submission for I/O dispatch (nab + hch)

Changelog v0 -> v1:

  Merge into single source + header file, and move to drivers/vhost/

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Zhi Yong Wu <wuzhy@cn.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Merge remote-tracking branch 'wireless/master' into mac80211
mac80211: don't clear sched_scan_sdata on sched scan stop request

ieee80211_request_sched_scan_stop() cleared
local->sched_scan_sdata. However, sched_scan_sdata
should be cleared only after the driver calls
ieee80211_sched_scan_stopped() (like with normal hw scan).

Clearing sched_scan_sdata too early caused
ieee80211_sched_scan_stopped_work to exit prematurely
without properly cleaning all the sched scan resources
and without calling cfg80211_sched_scan_stopped (so
userspace wasn't notified about sched scan completion).

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: clear timer bits when disconnecting

There's a corner case that can happen when we
suspend with a timer running, then resume and
disconnect. If we connect again, suspend and
resume we might start timers that shouldn't be
running. Reset the timer flags to avoid this.

This affects both mesh and managed modes.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: cancel mesh path timer

The mesh path timer needs to be canceled when
leaving the mesh as otherwise it could fire
after the interface has been removed already.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
net: Allow driver to limit number of GSO segments per skb

A peer (or local user) may cause TCP to use a nominal MSS of as little
as 88 (actual MSS of 76 with timestamps).  Given that we have a
sufficiently prodigious local sender and the peer ACKs quickly enough,
it is nevertheless possible to grow the window for such a connection
to the point that we will try to send just under 64K at once.  This
results in a single skb that expands to 861 segments.

In some drivers with TSO support, such an skb will require hundreds of
DMA descriptors; a substantial fraction of a TX ring or even more than
a full ring.  The TX queue selected for the skb may stall and trigger
the TX watchdog repeatedly (since the problem skb will be retried
after the TX reset).  This particularly affects sfc, for which the
issue is designated as CVE-2012-3412.

Therefore:
1. Add the field net_device::gso_max_segs holding the device-specific
   limit.
2. In netif_skb_features(), if the number of segments is too high then
   mask out GSO features to force fall back to software GSO.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sfc: Fix maximum number of TSO segments and minimum TX queue size

Currently an skb requiring TSO may not fit within a minimum-size TX
queue.  The TX queue selected for the skb may stall and trigger the TX
watchdog repeatedly (since the problem skb will be retried after the
TX reset).  This issue is designated as CVE-2012-3412.

Set the maximum number of TSO segments for our devices to 100.  This
should make no difference to behaviour unless the actual MSS is less
than about 700.  Increase the minimum TX queue size accordingly to
allow for 2 worst-case skbs, so that there will definitely be space
to add an skb after we wake a queue.

To avoid invalidating existing configurations, change
efx_ethtool_set_ringparam() to fix up values that are too small rather
than returning -EINVAL.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp: Apply device TSO segment limit earlier

Cache the device gso_max_segs in sock::sk_gso_max_segs and use it to
limit the size of TSO skbs.  This avoids the need to fall back to
software GSO for local TCP senders.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>