Dan reported that the recent changes to the broadcast code introduced
a potential NULL dereference.

Add the proper check.

Fixes: e0454311 "tick/broadcast: Sanity check the shutdown of the local clock_event"
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

All users gone. Remove it before we get another one.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

ktime_get_ts() is the proper interface today.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>

Making tick_broadcast_oneshot_control() independent from
CONFIG_GENERIC_CLOCKEVENTS_BROADCAST broke the build for
CONFIG_GENERIC_CLOCKEVENTS=n because the function is not defined
there.

Provide a proper stub inline.

Fixes: f32dd117 'tick/broadcast: Make idle check independent from mode and config'
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Andriy reported that on a virtual machine the warning about negative
expiry time in the clock events programming code triggered:

hpet: hpet0 irq 40 for MSI
hpet: hpet1 irq 41 for MSI
Switching to clocksource hpet
WARNING: at kernel/time/clockevents.c:239

[<ffffffff810ce6eb>] clockevents_program_event+0xdb/0xf0
[<ffffffff810cf211>] tick_handle_periodic_broadcast+0x41/0x50
[<ffffffff81016525>] timer_interrupt+0x15/0x20

When the second hpet is installed as a per cpu timer the broadcast
event is not longer required and stopped, which sets the next_evt of
the broadcast device to KTIME_MAX.

If after that a spurious interrupt happens on the broadcast device,
then the current code blindly handles it and tries to reprogram the
broadcast device afterwards, which adds the period to
next_evt. KTIME_MAX + period results in a negative expiry value
causing the WARN_ON in the clockevents code to trigger.

Add a proper check for the state of the broadcast device into the
interrupt handler and return if the interrupt is spurious.

[ Folded in pointer fix from Sudeep ]
Reported-by: Andriy Gapon <avg@FreeBSD.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20150705205221.802094647@linutronix.de

If the current cpu is the one which has the hrtimer based broadcast
queued then we better return busy immediately instead of going through
loops and hoops to figure that out.

[ Split out from a larger combo patch ]
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

Tell the idle code not to go deep if the broadcast IPI is about to
arrive.

[ Split out from a larger combo patch ]
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

If the system is in periodic mode and the broadcast device is hrtimer
based, return busy as we have no proper handling for this.

[ Split out from a larger combo patch ]
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

We need to check more than the periodic mode for proper operation in
all runtime combinations. To avoid code duplication move the check
into the enter state handling.

No functional change.

[ Split out from a larger combo patch ]
Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

Add a check for a installed broadcast device to the oneshot control
function and return busy if not.

[ Split out from a larger combo patch ]
Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

Currently the broadcast busy check, which prevents the idle code from
going into deep idle, works only in one shot mode.

If NOHZ and HIGHRES are off (config or command line) there is no
sanity check at all, so under certain conditions cpus are allowed to
go into deep idle, where the local timer stops, and are not woken up
again because there is no broadcast timer installed or a hrtimer based
broadcast device is not evaluated.

Move tick_broadcast_oneshot_control() into the common code and provide
proper subfunctions for the various config combinations.

The common check in tick_broadcast_oneshot_control() is for the C3STOP
misfeature flag of the local clock event device. If its not set, idle
can proceed. If set, further checks are necessary.

Provide checks for the trivial cases:

 - If broadcast is disabled in the config, then return busy

 - If oneshot mode (NOHZ/HIGHES) is disabled in the config, return
   busy if the broadcast device is hrtimer based.

 - If oneshot mode is enabled in the config call the original
   tick_broadcast_oneshot_control() function. That function needs
   extra checks which will be implemented in seperate patches.

[ Split out from a larger combo patch ]
Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

The broadcast code shuts down the local clock event unconditionally
even if no broadcast device is installed or if the broadcast device is
hrtimer based.

Add proper sanity checks.

[ Split out from a larger combo patch ]
Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

The hrtimer based broadcast vehicle can cause a hrtimer recursion
which went unnoticed until we changed the hrtimer expiry code to keep
track of the currently running timer.

local_timer_interrupt()
  local_handler()
    hrtimer_interrupt()
      expire_hrtimers()
        broadcast_hrtimer()
	  send_ipis()
	  local_handler()
	    hrtimer_interrupt()
	     ....

Solution is simple: Prevent the local handler call from the broadcast
code when the broadcast 'device' is hrtimer based.

[ Split out from a larger combo patch ]
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

Its mandatory for the drivers to provide set_state_{oneshot|periodic}()
(only if related modes are supported) and set_state_shutdown() callbacks
today, if they are implementing the new set-state interface.

But this leads to unnecessary noop callbacks for drivers which don't
want to implement them. Over that, it will lead to a full function call
for nothing really useful.

Lets make all set-state callbacks optional.
Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: http://lkml.kernel.org/r/1436256875-15562-1-git-send-email-daniel.lezcano@linaro.orgSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

The rework of the imx clocksource driver missed to add an entry for
imx27 which results in a boot failure on those machines.

Add the proper CLOCKSOURCE_OF_DECLARE() entry for imx27 and map it to
the imx21 init.

Fixes: bef11c88 'ARM: imx: initialize gpt device type for DT boot'
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: daniel.lezcano@linaro.org
Cc: fabio.estevam@freescale.com
Cc: shawnguo@kernel.org
Cc: kernel@pengutronix.de
Link: http://lkml.kernel.org/r/1435439504-406-1-git-send-email-tremyfr@gmail.comSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

Merge tag 'platform-drivers-x86-v4.2-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86

Pull late x86 platform driver updates from Darren Hart:
 "The following came in a bit later and I wanted them to bake in next a
  few more days before submitting, thus the second pull.

  A new intel_pmc_ipc driver, a symmetrical allocation and free fix in
  dell-laptop, a couple minor fixes, and some updated documentation in
  the dell-laptop comments.

  intel_pmc_ipc:
   - Add Intel Apollo Lake PMC IPC driver

  tc1100-wmi:
   - Delete an unnecessary check before the function call "kfree"

  dell-laptop:
   - Fix allocating & freeing SMI buffer page
   - Show info about WiGig and UWB in debugfs
   - Update information about wireless control"

* tag 'platform-drivers-x86-v4.2-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
  intel_pmc_ipc: Add Intel Apollo Lake PMC IPC driver
  tc1100-wmi: Delete an unnecessary check before the function call "kfree"
  dell-laptop: Fix allocating & freeing SMI buffer page
  dell-laptop: Show info about WiGig and UWB in debugfs
  dell-laptop: Update information about wireless control

Pull more vfs updates from Al Viro:
 "Assorted VFS fixes and related cleanups (IMO the most interesting in
  that part are f_path-related things and Eric's descriptor-related
  stuff).  UFS regression fixes (it got broken last cycle).  9P fixes.
  fs-cache series, DAX patches, Jan's file_remove_suid() work"

[ I'd say this is much more than "fixes and related cleanups".  The
  file_table locking rule change by Eric Dumazet is a rather big and
  fundamental update even if the patch isn't huge.   - Linus ]

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
  9p: cope with bogus responses from server in p9_client_{read,write}
  p9_client_write(): avoid double p9_free_req()
  9p: forgetting to cancel request on interrupted zero-copy RPC
  dax: bdev_direct_access() may sleep
  block: Add support for DAX reads/writes to block devices
  dax: Use copy_from_iter_nocache
  dax: Add block size note to documentation
  fs/file.c: __fget() and dup2() atomicity rules
  fs/file.c: don't acquire files->file_lock in fd_install()
  fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
  vfs: avoid creation of inode number 0 in get_next_ino
  namei: make set_root_rcu() return void
  make simple_positive() public
  ufs: use dir_pages instead of ufs_dir_pages()
  pagemap.h: move dir_pages() over there
  remove the pointless include of lglock.h
  fs: cleanup slight list_entry abuse
  xfs: Correctly lock inode when removing suid and file capabilities
  fs: Call security_ops->inode_killpriv on truncate
  fs: Provide function telling whether file_remove_privs() will do anything
  ...

Commit 835a6a2f ("Bluetooth: Stop sabotaging list poisoning")
thought that the code was sabotaging the list poisoning when NULL'ing
out the list pointers and removed it.

But what was going on was that the bluetooth code was using NULL
pointers for the list as a way to mark it empty, and that commit just
broke it (and replaced the test with NULL with a "list_empty()" test on
a uninitialized list instead, breaking things even further).

So fix it all up to use the regular and real list_empty() handling
(which does not use NULL, but a pointer to itself), also making sure to
initialize the list properly (the previous NULL case was initialized
implicitly by the session being allocated with kzalloc())

This is a combination of patches by Marcel Holtmann and Tedd Ho-Jeong
An.

[ I would normally expect to get this through the bt tree, but I'm going
  to release -rc1, so I'm just committing this directly   - Linus ]
Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Original-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Original-by: Marcel Holtmann <marcel@holtmann.org>:
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull SCSI target updates from Nicholas Bellinger:
 "It's been a busy development cycle for target-core in a number of
  different areas.

  The fabric API usage for se_node_acl allocation is now within
  target-core code, dropping the external API callers for all fabric
  drivers tree-wide.

  There is a new conversion to RCU hlists for se_node_acl and
  se_portal_group LUN mappings, that turns fast-past LUN lookup into a
  completely lockless code-path.  It also removes the original
  hard-coded limitation of 256 LUNs per fabric endpoint.

  The configfs attributes for backends can now be shared between core
  and driver code, allowing existing drivers to use common code while
  still allowing flexibility for new backend provided attributes.

  The highlights include:

   - Merge sbc_verify_dif_* into common code (sagi)
   - Remove iscsi-target support for obsolete IFMarker/OFMarker
     (Christophe Vu-Brugier)
   - Add bidi support in target/user backend (ilias + vangelis + agover)
   - Move se_node_acl allocation into target-core code (hch)
   - Add crc_t10dif_update common helper (akinobu + mkp)
   - Handle target-core odd SGL mapping for data transfer memory
     (akinobu)
   - Move transport ID handling into target-core (hch)
   - Move task tag into struct se_cmd + support 64-bit tags (bart)
   - Convert se_node_acl->device_list[] to RCU hlist (nab + hch +
     paulmck)
   - Convert se_portal_group->tpg_lun_list[] to RCU hlist (nab + hch +
     paulmck)
   - Simplify target backend driver registration (hch)
   - Consolidate + simplify target backend attribute implementations
     (hch + nab)
   - Subsume se_port + t10_alua_tg_pt_gp_member into se_lun (hch)
   - Drop lun_sep_lock for se_lun->lun_se_dev RCU usage (hch + nab)
   - Drop unnecessary core_tpg_register TFO parameter (nab)
   - Use 64-bit LUNs tree-wide (hannes)
   - Drop left-over TARGET_MAX_LUNS_PER_TRANSPORT limit (hannes)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (76 commits)
  target: Bump core version to v5.0
  target: remove target_core_configfs.h
  target: remove unused TARGET_CORE_CONFIG_ROOT define
  target: consolidate version defines
  target: implement WRITE_SAME with UNMAP bit using ->execute_unmap
  target: simplify UNMAP handling
  target: replace se_cmd->execute_rw with a protocol_data field
  target/user: Fix inconsistent kmap_atomic/kunmap_atomic
  target: Send UA when changing LUN inventory
  target: Send UA upon LUN RESET tmr completion
  target: Send UA on ALUA target port group change
  target: Convert se_lun->lun_deve_lock to normal spinlock
  target: use 'se_dev_entry' when allocating UAs
  target: Remove 'ua_nacl' pointer from se_ua structure
  target_core_alua: Correct UA handling when switching states
  xen-scsiback: Fix compile warning for 64-bit LUN
  target: Remove TARGET_MAX_LUNS_PER_TRANSPORT
  target: use 64-bit LUNs
  target: Drop duplicate + unused se_dev_check_wce
  target: Drop unnecessary core_tpg_register TFO parameter
  ...

Pull NTB updates from Jon Mason:
 "This includes a pretty significant reworking of the NTB core code, but
  has already produced some significant performance improvements.

  An abstraction layer was added to allow the hardware and clients to be
  easily added.  This required rewriting the NTB transport layer for
  this abstraction layer.  This modification will allow future "high
  performance" NTB clients.

  In addition to this change, a number of performance modifications were
  added.  These changes include NUMA enablement, using CPU memcpy
  instead of asyncdma, and modification of NTB layer MTU size"

* tag 'ntb-4.2' of git://github.com/jonmason/ntb: (22 commits)
  NTB: Add split BAR output for debugfs stats
  NTB: Change WARN_ON_ONCE to pr_warn_once on unsafe
  NTB: Print driver name and version in module init
  NTB: Increase transport MTU to 64k from 16k
  NTB: Rename Intel code names to platform names
  NTB: Default to CPU memcpy for performance
  NTB: Improve performance with write combining
  NTB: Use NUMA memory in Intel driver
  NTB: Use NUMA memory and DMA chan in transport
  NTB: Rate limit ntb_qp_link_work
  NTB: Add tool test client
  NTB: Add ping pong test client
  NTB: Add parameters for Intel SNB B2B addresses
  NTB: Reset transport QP link stats on down
  NTB: Do not advance transport RX on link down
  NTB: Differentiate transport link down messages
  NTB: Check the device ID to set errata flags
  NTB: Enable link for Intel root port mode in probe
  NTB: Read peer info from local SPAD in transport
  NTB: Split ntb_hw_intel and ntb_transport drivers
  ...

if server claims to have written/read more than we'd told it to,
warn and cap the claimed byte count to avoid advancing more than
we are ready to.

Braino in "9p: switch p9_client_write() to passing it struct iov_iter *";
if response is impossible to parse and we discard the request, get the
out of the loop right there.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

If we'd already sent a request and decide to abort it, we *must*
issue TFLUSH properly and not just blindly reuse the tag, or
we'll get seriously screwed when response eventually arrives
and we confuse it for response to later request that had reused
the same tag.

Cc: stable@vger.kernel.org # v3.2 and later
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

The brd driver is the only in-tree driver that may sleep currently.
After some discussion on linux-fsdevel, we decided that any driver
may choose to sleep in its ->direct_access method.  To ensure that all
callers of bdev_direct_access() are prepared for this, add a call
to might_sleep().
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

If a block device supports the ->direct_access methods, bypass the normal
DIO path and use DAX to go straight to memcpy() instead of allocating
a DIO and a BIO.

Includes support for the DIO_SKIP_DIO_COUNT flag in DAX, as is done in
do_blockdev_direct_IO().
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

When userspace does a write, there's no need for the written data to
pollute the CPU cache.  This matches the original XIP code.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

For block devices which are small enough, mkfs will default to creating
a filesystem with block sizes smaller than page size.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull kvm fixes from Paolo Bonzini:
 "Except for the preempt notifiers fix, these are all small bugfixes
  that could have been waited for -rc2.  Sending them now since I was
  taking care of Peter's patch anyway"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: add hyper-v crash msrs values
  KVM: x86: remove data variable from kvm_get_msr_common
  KVM: s390: virtio-ccw: don't overwrite config space values
  KVM: x86: keep track of LVT0 changes under APICv
  KVM: x86: properly restore LVT0
  KVM: x86: make vapics_in_nmi_mode atomic
  sched, preempt_notifier: separate notifier registration from static_key inc/dec

When split BAR is enabled, the driver needs to dump out the split BAR
registers rather than the original 64bit BAR registers.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

The unsafe doorbell and scratchpad access should display reason when
WARN is called.  Otherwise we get a stack dump without any explanation.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Printouts driver name and version to indicate what is being loaded.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Benchmarking showed a significant performance increase with the MTU size
to 64k instead of 16k.  Change the driver default to 64k.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Instead of using the platform code names, use the correct platform names
to identify the respective Intel NTB hardware.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Disable DMA usage by default, since the CPU provides much better
performance with write combining.  Provide a module parameter to enable
DMA usage when offloading the memcpy is preferred.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Changing the memory window BAR mappings to write combining significantly
boosts the performance.  We will also use memcpy that uses non-temporal
store, which showed performance improvement when doing non-cached
memcpys.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Allocate memory for the NUMA node of the NTB device.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Allocate memory and request the DMA channel for the same NUMA node as
the NTB device.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

When the ntb transport is connecting and waiting for the peer, the debug
console receives lots of debug level messages about the remote qp link
status being down.  Rate limit those messages.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

This is a simple debugging driver that enables the doorbell and
scratch pad registers to be read and written from the debugfs.  This
tool enables more complicated debugging to be scripted from user space.
This driver may be used to test that your ntb hardware and drivers are
functioning at a basic level.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>