If the initialization of a special QP (e.g. AQP1) fails due to a
software timeout, we have to remove the reference to that special QP
struct from the port struct to stop the driver from accessing the QP,
since it will be/has been destroyed by the caller, eg in this case
ib_mad.
Signed-off-by: NStefan Roscher <stefan.roscher@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Certain firmware versions sometimes cause spurious PATH_MIG events to
occur during QP creation.  Filter these events by making sure PATH_MIG
events are only handed down when they actually make sense (i.e. when
the QP has been armed at least once).
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

During corner case testing, we noticed that some versions of ehca do
not properly transition to interrupt done in special load situations.
This can be resolved by periodically triggering EOI through H_EOI, if
EQEs are pending.
Signed-off-by: NStefan Roscher <stefan.roscher@de.ibm.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Change references from for_each_cpu_mask to for_each_cpu_mask_nr
where appropriate
Reviewed-by: NPaul Jackson <pj@sgi.com>
Reviewed-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NMike Travis <travis@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This is necessary because, in a multicore environment, a race between
uverbs async handler and destroy QP could occur.

Signed-off-by: Stefan Roscher <stefan.roscher at de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch enhances ehca with a capability to "autodetect" the ports
being connected physically. In order to utilize that function the
module option nr_ports must be set to -1 (default is 2 - two
ports). This feature is experimental and will made the default later.

More detail:

If the user connects only one port to the switch, current code requires
  1) port one to be connected and
  2) module option nr_ports=1 to be given.

If autodetect is enabled, ehca will not wait at creation of the GSI QP
for the respective port to become active. Since firmware does not
accept modify_qp() while the port is down at initialization, we need
to cache all calls to modify_qp() for the SMI/GSI QP and just return a
good return code.

When a port is activated and we get a PORT_ACTIVE event, we replay the
cached modify-qp() parms and re-trigger any posted recv WRs. Only then
do we forward the PORT_ACTIVE event to registered clients.

The result of this autodetect patch is that all ports will be
accessible by the users. Depending on their respective cabling only
those ports that are connected properly will become operable. If a
user tries to modify a regular QP of a non-connected port, modify_qp()
will fail. Furthermore, ibv_devinfo should show the port state
accordingly.

Note that this patch primarily improves the loading behaviour of
ehca. If the cable is removed while the driver is operating and
plugged in again, firmware will handle that properly by sending an
appropriate async event.
Signed-off-by: NHoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch allows ehca to forward event client-reregister-required to
registered clients.  One such event is generated by a switch eg. after
its reboot.
Signed-off-by: NHoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

* Replace {un}register_cpu_notifier with {un}register_hotcpu_notifier
  thereby losing a couple of #ifdef HOTPLUG_CPU pairs.
* Move comp_pool_callback_nb declaration to below that of callback
  function so that initialization of .notifier_call and .priority can
  occur at build time itself and not runtime.
* Mark the notifier_block (and callback function, and another static
  function used by it) as __cpuinit{data} for the sake of consistency
  and remove enclosing #ifdef. (This may increase size for modular
  build of this module, however, because these are no longer dropped
  unconditionally now.)
Signed-off-by: NSatyam Sharma <satyam@infradead.org>
Acked-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix some modify_qp() issues related to path migration.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix ehca SRQ support so that IPoIB connected mode works:

 - Report max_srq > 0 if SRQ is supported
 - Report "last wqe reached" asynchronous event when base QP dies;
   this is required by the IB spec and IPoIB CM relies on receiving it
   when cleaning up.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

One patch for two trivial typos of 'error' with three R's, appearing in message strings.

There's a bunch more of the same in comments, not dealt with here.
Signed-off-by: NEddy L O Jansson <eddy@klopper.net>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Run the existing ehca code through checkpatch.pl and clean up the
worst of the coding style violations.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When firmware reports a nondisruptive port configuration change event,
previous versions of the eHCA driver didn't forward the event to consumers
like IPoIB.  Add code that determines the type of configuration change by
comparing old and new port attributes and reports it.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This eliminates lock contention among IRQs as well as the need to
disable IRQs around idr_find, because there are no IRQ writers.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

- ehca_cq.nr_events is made an atomic_t, eliminating a lot of locking.
- The CQ is removed from the CQ idr first now to make sure no more
  completions are scheduled on that CQ. The "wait for all completions to
  end" code becomes much simpler this way.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

- In ehca_process_eq(), we're IRQ safe throughout the whole function, so we
  don't need another _irqsave in the middle of flight.

- take_over_work() is only called by comp_pool_callback(), so it can move
  into the same #ifdef block.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

eHCA scaling code must not depend on register_cpu_notifier() if
CONFIG_HOTPLUG_CPU is not set, so put all related code into #ifdefs.
Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch fixes two issues reported by Roland Dreier and Christoph Hellwig:

- Mismatched sync/locking between completion handler and destroy cq We
  introduced a counter nr_events per cq to track number of irq events
  seen. This counter is incremented when an event queue entry is seen
  and decremented after completion handler has been called regardless
  if scaling code is active or not. Note that nr_callbacks tracks
  number of events assigned to a cpu and both counters can potentially
  diverge.

  The sync between running completion handler and destroy cq is done
  by using the global spin lock ehca_cq_idr_lock.

- Replace yield by wait_event on the counter above to become zero.
Signed-off-by: NHoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Allow users to en/disable scaling code when loading ib_ehca module,
rather than requiring the module to be rebuilt to change the setting.
Signed-off-by: NHoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix a race condition in find_next_cpu_online() and some other locking
issues in ehca scaling code.
Signed-off-by: NHoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Rework ehca interrupt handling to avoid/reduce missed irq events.
Signed-off-by: NHoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Percpu data is not freed on module unloading.

Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christoph Raisch <raisch@de.ibm.com>
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NHoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The lock is taken with _irqsave and hence must be released with
_irqrestore on all paths.

Signed-off-by Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Here is a patch for ehca to use proper flag, ie. GFP_ATOMIC
resp. GFP_KERNEL, when calling get_zeroed_page() to prevent "Bug:
scheduling while atomic...". This error does not cause a kernel panic
but makes ipoib un-usable afterwards.  It is reproducible on
2.6.20-rc4 if one does ifconfig down during a flood ping test.  I have
not observed this error in earlier releases incl. 2.6.20-rc1.

This error occurs when a qp event/irq is received and ehca event
handler allocates a control block/page to obtain HCA error data block.
Use of GFP_ATOMIC when in interrupt context prevents this issue.

Signed-off-by Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Assure 4K alignment for firmware control blocks in 64K page mode,
because kzalloc()'s result address might not be 4K aligned if 64K
pages are enabled. Thus, we introduce wrappers called
ehca_{alloc,free}_fw_ctrlblock(), which use a slab cache for objects
with 4K length and 4K alignment in order to alloc/free firmware
control blocks in 64K page mode. In 4K page mode those wrappers just
are defines of get_zeroed_page() and free_page().
Signed-off-by: NHoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

Add a driver for IBM GX bus InfiniBand adapters, which are usable with
some pSeries/System p systems.

Signed-off-by: Heiko J Schick <schickhj.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>