This implements UAC2 jack detection support, presenting
jack status as a boolean read-only mono mixer.

The presence of any channel in the UAC2_TE_CONNECTOR
control for a terminal will result in the mixer saying
the jack is connected.

Mixer naming follows the convention in sound/core/ctljack.c,
terminating the mixer with " Jack".
For additional clues as to which jack is being presented,
the name is prefixed with " - Input Jack" or " - Output Jack"
depending on if it's an input or output terminal.

This is required because terminal names are ambiguous
between inputs and outputs and often duplicated -
Bidirectional terminal types (0x400 -> 0x4FF)
"... may be used separately for input only or output only.
These types require two Terminal descriptors. Both have the same type."
(quote from "USB Device Class Definition for Terminal Types")

Since bidirectional terminal types are common for headphone adapters,
this distinguishes between two otherwise identically-named
jack controls.

Tested with a UAC2 audio device with connector control capability.
Signed-off-by: Andrew Chant <achant@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

OSS PCM stream management isn't modal but it allows ioctls issued at
any time for changing the parameters.  In the previous hardening
patch ("ALSA: pcm: Avoid potential races between OSS ioctls and
read/write"), we covered these races and prevent the corruption by
protecting the concurrent accesses via params_lock mutex.  However,
this means that some ioctls that try to change the stream parameter
(e.g. channels or format) would be blocked until the read/write
finishes, and it may take really long.

Basically changing the parameter while reading/writing is an invalid
operation, hence it's even more user-friendly from the API POV if it
returns -EBUSY in such a situation.

This patch adds such checks in the relevant ioctls with the addition
of read/write access refcount.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Although we apply the params_lock mutex to the whole read and write
operations as well as snd_pcm_oss_change_params(), we may still face
some races.

First off, the params_lock is taken inside the read and write loop.
This is intentional for avoiding the too long locking, but it allows
the in-between parameter change, which might lead to invalid
pointers.  We check the readiness of the stream and set up via
snd_pcm_oss_make_ready() at the beginning of read and write, but it's
called only once, by assuming that it remains ready in the rest.

Second, many ioctls that may change the actual parameters
(i.e. setting runtime->oss.params=1) aren't protected, hence they can
be processed in a half-baked state.

This patch is an attempt to plug these holes.  The stream readiness
check is moved inside the read/write inner loop, so that the stream is
always set up in a proper state before further processing.  Also, each
ioctl that may change the parameter is wrapped with the params_lock
for avoiding the races.

The issues were triggered by syzkaller in a few different scenarios,
particularly the one below appearing as GPF in loopback_pos_update.

Reported-by: syzbot+c4227aec125487ec3efa@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Integrate the native DSD support quirk codes of "ITF-USB DSD" based DACs.

Now, "is_itf_usb_dsd_2alts_dac()" and "is_itf_usb_dsd_3alts_dac()" is
integrated into one function "is_itf_usb_dsd_dac()".
So, remove the logic to distinguish UD-501 and UD-501V2 by the
"Product Name".

The integration is possible by changing the following two functions.

- snd_usb_select_mode_quirk():
Change the determination condition of the DSD mode switch command,
from the altset number being used, to the audio format being played.
Actually, this operation is same as playback using ASIO driver in
Windows environment.

- snd_usb_interface_dsd_format_quirk():
To which altset supports native DSD is determined by the number of altsets.
Previously, it's a constant "2" or "3".
Signed-off-by: Nobutaka Okabe <nob77413@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

There are two versions of TEAC UD-501, the normal version and
the vendor updated version(UD-501V2).

They have the same VID/PID, but the num of the altsetting is different,
UD-501 has 2 altsets for stream, and UD-501V2 has 3.

So, add the logic to distinguish them by the Product Name, not by the PID.
Signed-off-by: Nobutaka Okabe <nob77413@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Add native DSD support quirk for Luxman DA-06 DAC, by adding the
PID/VID 1852:5065.

Rename "is_marantz_denon_dac()" function to "is_itf_usb_dsd_2alts_dac()"
to cover broader device family sharing the same USB audio
implementation(*).
For the same reason, rename "is_teac_dsd_dac()" function to
"is_itf_usb_dsd_3alts_dac()".

(*)
These devices have the same USB controller "ITF-USB DSD", supplied by
INTERFACE Co., Ltd.
"ITF-USB DSD" USB controller has two patterns,

Pattern 1. (2 altsets version)
- Altset 0: for control
- Altset 1: for stream (S32)
- Altset 2: for stream (S32, DSD_U32)

Pattern 2. (3 altsets version)
- Altset 0: for control
- Altset 1: for stream (S16)
- Altset 2: for stream (S32)
- Altset 3: for stream (S32, DSD_U32)

"is_itf_usb_dsd_2alts_dac()" returns true, if the DAC has "Pattern 1"
USB controller, and "is_itf_usb_dsd_3alts_dac()" returns true, if
"Pattern2".
Signed-off-by: Nobutaka Okabe <nob77413@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Back-merge for applying more series of fixes for USB DSD support.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Add native DSD support quirk for TEAC UD-301 DAC,
by adding the PID/VID 0644:804a.
Signed-off-by: Nobutaka Okabe <nob77413@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

This patch fixes code readability and should have no functional change.

Correct uac control query functions to account for the 1-based indexing
of USB Audio Class control identifiers.

The function parameter, u8 control, should be the
constant defined in audio-v2.h to identify the control to be checked for
readability or writeability.

This patch fixes all callers that had adjusted, and makes explicit
the mapping between audio_feature_info[] array index and the associated
control identifier.
Signed-off-by: Andrew Chant <achant@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

In loopback_open() and loopback_close(), we assign and release the
substream object to the corresponding cable in a racy way.  It's
neither locked nor done in the right position.  The open callback
assigns the substream before its preparation finishes, hence the other
side of the cable may pick it up, which may lead to the invalid memory
access.

This patch addresses these: move the assignment to the end of the open
callback, and wrap with cable->lock for avoiding concurrent accesses.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

The aloop driver tries to stop the pending timer via timer_del() in
the trigger callback and in the close callback.  The former is
correct, as it's an atomic operation, while the latter expects that
the timer gets really removed and proceeds the resource releases after
that.  But timer_del() doesn't synchronize, hence the running timer
may still access the released resources.

A similar situation can be also seen in the prepare callback after
trigger(STOP) where the prepare tries to re-initialize the things
while a timer is still running.

The problems like the above are seen indirectly in some syzkaller
reports (although it's not 100% clear whether this is the only cause,
as the race condition is quite narrow and not always easy to
trigger).

For addressing these issues, this patch adds the explicit alls of
timer_del_sync() in some places, so that the pending timer is properly
killed / synced.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

It will have a chance speaker no sound after system resume.
To toggle NID 0x53 index 0x2 bit 15 will solve this issue.
This usage will also suitable with ALC256.

Fixes: 4a219ef8 ("ALSA: hda/realtek - Add ALC256 HP depop function")
Signed-off-by: Kailang Yang <kailang@realtek.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

This platform was hardware fixed type for CTIA type for headset port.
Assigned 0x19 verb will fix can't record issue.
Signed-off-by: Kailang Yang <kailang@realtek.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Recently released USB Audio Class 3.0 specification
introduces many significant changes comparing to
previous versions, like
 - new Power Domains, support for LPM/L1
 - new Cluster descriptor
 - changed layout of all class-specific descriptors
 - new High Capability descriptors
 - New class-specific String descriptors
 - new and removed units
 - additional sources for interrupts
 - removed Type II Audio Data Formats
 - ... and many other things (check spec)

It also provides backward compatibility through
multiple configurations, as well as requires
mandatory support for BADD (Basic Audio Device
Definition) on each ADC3.0 compliant device

This patch adds initial support of UAC3 specification
that is enough for Generic I/O Profile (BAOF, BAIF)
device support from BADD document.
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

We've observed too long probe time with Coffee Lake (CFL) machines,
and the likely cause is some communication problem between the
HD-audio controller and the codec chips.  While the controller expects
an IRQ wakeup for each codec response, it seems sometimes missing, and
it takes one second for the controller driver to time out and read the
response in the polling mode.

Although we aren't sure about the real culprit yet, in this patch, we
put a workaround by forcing the polling mode as default for CFL
machines; the polling mode itself isn't too heavy, and much better
than other workarounds initially suggested (e.g. disabling
power-save), at least.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199007
Fixes: e79b0006 ("ALSA: hda - Add Coffelake PCI ID")
Reported-and-tested-by: Hui Wang <hui.wang@canonical.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Offload USB audio interface parsing function by
moving quirks to a specially designed location (quirks.c)
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Back-merge of for-linus branch for applying the further UAC3 patches.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Currently, the offsets in the UAC2 processing unit descriptor are
calculated incorrectly. It causes an issue when connecting the device which
provides such a feature:

~~~~
[84126.724420] usb 1-1.3.1: invalid Processing Unit descriptor (id 18)
~~~~

After this patch is applied, the UAC2 processing unit inits w/o this error.

Fixes: 23caaf19 ("ALSA: usb-mixer: Add support for Audio Class v2.0")
Signed-off-by: Kirill Marinushkin <k.marinushkin@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Some HP laptops have a mute mute LED controlled by a pin VREF.  The
Realtek codec driver updates the VREF via vmaster hook by calling
snd_hda_set_pin_ctl_cache().

This works fine as long as the driver is running in a normal mode.
However, when the VREF change happens during the codec being in
runtime PM suspend, the regmap access will skip and postpone the
actual register change.  This ends up with the unchanged LED status
until the next runtime PM resume even if you change the Master mute
switch.  (Interestingly, the machine keeps the LED status even after
the codec goes into D3 -- but it's another story.)

For improving this usability, let the driver temporarily powering up /
down only during the pin VREF change.  This can be achieved easily by
wrapping the call with snd_hda_power_up_pm() / *_down_pm().

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199073
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Just a minor simplification.  Change from kcalloc() shouldn't matter
as each array element is fully initialized.
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

A helper function used by snd_pcm_hw_refine() still keeps using VLA
for timestamps of hw constraint rules that are non-fixed size.

Let's replace the VLA with a simple kmalloc() array.

Reference: https://lkml.org/lkml/2018/3/7/621Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Icelake is a next generation Intel platform. Add PCI ID for
it.
Signed-off-by: Guneshwor Singh <guneshwor.o.singh@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Merge tag 'asoc-fix-v4.16-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v4.16

This is a fairly standard collection of fixes, there's no changes to the
core here just a bunch of small device specific changes for single
drivers plus an update to the MAINTAINERS file for the sgl5000.

Merge remote-tracking branches 'asoc/fix/amd', 'asoc/fix/hdmi-codec', 'asoc/fix/rt5651', 'asoc/fix/samsung', 'asoc/fix/sgtl5000', 'asoc/fix/sunxi' and 'asoc/fix/wm-adsp' into asoc-linus

The pointer 'pipe' is being initialized with a value that is never
read and it is re-assigned later, hence the initialization is redundant
and can be removed. Also remove pointer 'runtime' as it is no longer
required.

Cleans up clang warning:
sound/pci/echoaudio/echoaudio.c:740:20: warning: Value stored to 'pipe'
during its initialization is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

With the commit 1ba8f9d3 ("ALSA: hda: Add a power_save
blacklist"), we changed the default value of power_save option to -1
for processing the power-save blacklist.
Unfortunately, this seems breaking user-space applications that
actually read the power_save parameter value via sysfs and judge /
adjust the power-saving status.  They see the value -1 as if the
power-save is turned off, although the actual value is taken from
CONFIG_SND_HDA_POWER_SAVE_DEFAULT and it can be a positive.

So, overall, passing -1 there was no good idea.  Let's partially
revert it -- at least for power_save option default value is restored
again to CONFIG_SND_HDA_POWER_SAVE_DEFAULT.  Meanwhile, in this patch,
we keep the blacklist behavior and make is adjustable via the new
option, pm_blacklist.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199073
Fixes: 1ba8f9d3 ("ALSA: hda: Add a power_save blacklist")
Acked-by: Hans de Goede <hdegoede@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Pull x86/pti updates from Thomas Gleixner:
 "Yet another pile of melted spectrum related updates:

   - Drop native vsyscall support finally as it causes more trouble than
     benefit.

   - Make microcode loading more robust. There were a few issues
     especially related to late loading which are now surfacing because
     late loading of the IB* microcodes addressing spectre issues has
     become more widely used.

   - Simplify and robustify the syscall handling in the entry code

   - Prevent kprobes on the entry trampoline code which lead to kernel
     crashes when the probe hits before CR3 is updated

   - Don't check microcode versions when running on hypervisors as they
     are considered as lying anyway.

   - Fix the 32bit objtool build and a coment typo"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kprobes: Fix kernel crash when probing .entry_trampoline code
  x86/pti: Fix a comment typo
  x86/microcode: Synchronize late microcode loading
  x86/microcode: Request microcode on the BSP
  x86/microcode/intel: Look into the patch cache first
  x86/microcode: Do not upload microcode if CPUs are offline
  x86/microcode/intel: Writeback and invalidate caches before updating microcode
  x86/microcode/intel: Check microcode revision before updating sibling threads
  x86/microcode: Get rid of struct apply_microcode_ctx
  x86/spectre_v2: Don't check microcode versions when running under hypervisors
  x86/vsyscall/64: Drop "native" vsyscalls
  x86/entry/64/compat: Save one instruction in entry_INT80_compat()
  x86/entry: Do not special-case clone(2) in compat entry
  x86/syscalls: Use COMPAT_SYSCALL_DEFINEx() macros for x86-only compat syscalls
  x86/syscalls: Use proper syscall definition for sys_ioperm()
  x86/entry: Remove stale syscall prototype
  x86/syscalls/32: Simplify $entry == $compat entries
  objtool: Fix 32-bit build

Pull timer fix from Thomas Gleixner:
 "Just a single fix which adds a missing Kconfig dependency to avoid
  unmet dependency warnings"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/atmel-st: Add 'depends on HAS_IOMEM' to fix unmet dependency

Pull RAS fixes from Thomas Gleixner:
 "Two small fixes for RAS/MCE:

   - Serialize sysfs changes to avoid concurrent modificaiton of
     underlying data

   - Add microcode revision to Machine Check records. This should have
     been there forever, but now with the broken microcode versions in
     the wild it has become important"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/MCE: Serialize sysfs changes
  x86/MCE: Save microcode revision in machine check records

Pull perf updates from Thomas Gleixner:
 "Another set of perf updates:

   - Fix a Skylake Uncore event format declaration

   - Prevent perf pipe mode from crahsing which was caused by a missing
     buffer allocation

   - Make the perf top popup message which tells the user that it uses
     fallback mode on older kernels a debug message.

   - Make perf context rescheduling work correcctly

   - Robustify the jump error drawing in perf browser mode so it does
     not try to create references to NULL initialized offset entries

   - Make trigger_on() robust so it does not enable the trigger before
     everything is set up correctly to handle it

   - Make perf auxtrace respect the --no-itrace option so it does not
     try to queue AUX data for decoding.

   - Prevent having different number of field separators in CVS output
     lines when a counter is not supported.

   - Make the perf kallsyms man page usage behave like it does for all
     other perf commands.

   - Synchronize the kernel headers"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Fix ctx_event_type in ctx_resched()
  perf tools: Fix trigger class trigger_on()
  perf auxtrace: Prevent decoding when --no-itrace
  perf stat: Fix CVS output format for non-supported counters
  tools headers: Sync x86's cpufeatures.h
  tools headers: Sync copy of kvm UAPI headers
  perf record: Fix crash in pipe mode
  perf annotate browser: Be more robust when drawing jump arrows
  perf top: Fix annoying fallback message on older kernels
  perf kallsyms: Fix the usage on the man page
  perf/x86/intel/uncore: Fix Skylake UPI event format

Pull locking fix from Thomas Gleixner:
 "rt_mutex_futex_unlock() grew a new irq-off call site, but the function
  assumes that its always called from irq enabled context.

  Use (un)lock_irqsafe() to handle the new call site correctly"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rtmutex: Make rt_mutex_futex_unlock() safe for irq-off callsites

Pull dmaengine fixes from Vinod Koul:
 "Two small fixes are for this cycle:

   - fix max_chunk_size for rcar-dmac for R-Car Gen3

   - fix clock resource of mv_xor_v2"

* tag 'dmaengine-fix-4.16-rc5' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: mv_xor_v2: Fix clock resource by adding a register clock
  dmaengine: rcar-dmac: fix max_chunk_size for R-Car Gen3

Pull GPIO fix from Linus Walleij:
 "This is a single GPIO fix for the v4.16 series affecting the Renesas
  driver, and fixes wakeup from external stuff"

* tag 'gpio-v4.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: rcar: Use wakeup_path i.s.o. explicit clock handling

On the CP110 components which are present on the Armada 7K/8K SoC we need
to explicitly enable the clock for the registers. However it is not
needed for the AP8xx component, that's why this clock is optional.

With this patch both clock have now a name, but in order to be backward
compatible, the name of the first clock is not used. It allows to still
use this clock with a device tree using the old binding.
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

snd_pcm_oss_get_formats() has an obvious use-after-free around
snd_mask_test() calls, as spotted by syzbot.  The passed format_mask
argument is a pointer to the hw_params object that is freed before the
loop.  What a surprise that it has been present since the original
code of decades ago...

Reported-by: syzbot+4090700a4f13fccaf648@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Merge tag 'kbuild-fixes-v4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - make fixdep parse kconfig.h to fix missing rebuild

 - replace hyphens with underscores in builtin DTB label names

 - fix typos

* tag 'kbuild-fixes-v4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: Handle builtin dtb file names containing hyphens
  scripts/bloat-o-meter: fix typos in help
  fixdep: do not ignore kconfig.h
  fixdep: remove some false CONFIG_ matches
  fixdep: remove stale references to uml-config.h

Pull watchdog fixes from Wim Van Sebroeck:

 - f71808e_wdt: Fix magic close handling

 - sbsa: 32-bit read fix for WCV

 - hpwdt: Remove legacy NMI sourcing

* tag 'linux-watchdog-4.16-fixes-2' of git://www.linux-watchdog.org/linux-watchdog:
  watchdog: hpwdt: Remove legacy NMI sourcing.
  watchdog: sbsa: use 32-bit read for WCV
  watchdog: f71808e_wdt: Fix magic close handling

Pull block fixes from Jens Axboe:

 - a xen-blkfront fix from Bhavesh with a multiqueue fix when
   detaching/re-attaching

 - a few important NVMe fixes, including a revert for a sysfs fix that
   caused some user space confusion

 - two bcache fixes by way of Michael Lyle

 - a loop regression fix, fixing an issue with lost writes on DAX.

* tag 'for-linus-20180309' of git://git.kernel.dk/linux-block:
  loop: Fix lost writes caused by missing flag
  nvme_fc: rework sqsize handling
  nvme-fabrics: Ignore nr_io_queues option for discovery controllers
  xen-blkfront: move negotiate_mq to cover all cases of new VBDs
  Revert "nvme: create 'slaves' and 'holders' entries for hidden controllers"
  bcache: don't attach backing with duplicate UUID
  bcache: fix crashes in duplicate cache device register
  nvme: pci: pass max vectors as num_possible_cpus() to pci_alloc_irq_vectors
  nvme-pci: Fix EEH failure on ppc

Merge tag 'for-4.16/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - Fix an uninitialized variable false warning in dm bufio

 - Fix DM's passthrough ioctl support to be race free against an
   underlying device being removed.

 - Fix corner-case of DM raid resync reporting if/when the raid becomes
   degraded during resync; otherwise automated raid repair will fail.

 - A few DM multipath fixes to make non-SCSI optimizations, that were
   introduced during the 4.16 merge, useful for all non-SCSI devices,
   rather than narrowly define this non-SCSI mode in terms of "nvme".

   This allows the removal of "queue_mode nvme" that really didn't need
   to be introduced. Instead DM core will internalize whether
   nvme-specific IO submission optimizations are doable and DM multipath
   will only do SCSI-specific device handler operations if SCSI is in
   use.

* tag 'for-4.16/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm table: allow upgrade from bio-based to specialized bio-based variant
  dm mpath: remove unnecessary NVMe branching in favor of scsi_dh checks
  dm table: fix "nvme" test
  dm raid: fix incorrect sync_ratio when degraded
  dm: use blkdev_get rather than bdgrab when issuing pass-through ioctl
  dm bufio: avoid false-positive Wmaybe-uninitialized warning