With the current state of irq_domain, the reverse map is always updated
when new IRQs get mapped.  This means that the irq_find_mapping() function
can be simplified to execute the revmap lookup functions unconditionally

This patch adds lookup functions for the revmaps that don't yet have one
and removes the slow path lookup code path.

v8: Broke out unrelated changes into separate patches.  Rebased on Paul's irq
    association patches.
v7: Rebased to irqdomain/next for v3.4 and applied before the removal of 'hint'
v6: Remove the slow path entirely.  The only place where the slow path
    could get called is for a linear mapping if the hwirq number is larger
    than the linear revmap size.  There shouldn't be any interrupt
    controllers that do that.
v5: rewrite to not use a ->revmap() callback.  It is simpler, smaller,
    safer and faster to open code each of the revmap lookups directly into
    irq_find_mapping() via a switch statement.
v4: Fix build failure on incorrect variable reference.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Rob Herring <rob.herring@calxeda.com>

task_work and rcu_head are identical now; merge them (calling the result
struct callback_head, rcu_head #define'd to it), kill separate allocation
in security/keys since we can just use cred->rcu now.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

get rid of the only user of ->data; this is _not_ the final variant - in the
end we'll have task_work and rcu_head identical and just use cred->rcu,
at which point the separate allocation will be gone completely.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

irq_create_direct_mapping can only be used with the NOMAP type.  Make
the function test to ensure it is passed the correct type of
irq_domain.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>

In preparation to remove the slow revmap path, eliminate the public
radix revmap lookup functions.  This simplifies the code and makes the
slowpath removal patch a lot simpler.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>

This adds a new strict mapping API for supporting creation of linux IRQs
at existing positions within the domain. The new routines are as follows:

For dynamic allocation and insertion to specified ranges:

	- irq_create_identity_mapping()
	- irq_create_strict_mappings()

These will allocate and associate a range of linux IRQs at the specified
location. This can be used by controllers that have their own static linux IRQ
definitions to map a hwirq range to, as well as for platforms that wish to
establish 1:1 identity mapping between linux and hwirq space.

For insertion to specified ranges by platforms that do their own irq_desc
management:

	- irq_domain_associate()
	- irq_domain_associate_many()

These in turn call back in to the domain's ->map() routine, for further
processing by the platform. Disassociation of IRQs get handled through
irq_dispose_mapping() as normal.

With these in place it should be possible to begin migration of legacy IRQ
domains to linear ones, without requiring special handling for static vs
dynamic IRQ definitions in DT vs non-DT paths. This also makes it possible
for domains with static mappings to adopt whichever tree model best fits
their needs, rather than simply restricting them to linear revmaps.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
[grant.likely: Reorganized irq_domain_associate{,_many} to have all logic in one place]
[grant.likely: Add error checking for unallocated irq_descs at associate time]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>

At irq_setup_virq() time all of the data needed to update the reverse
map is available, but the current code ignores it and relies upon the
slow path to insert revmap records.  This patch adds revmap updating
to the setup path so the slow path will no longer be necessary.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>

This patch moves the irq disassociation code out into a separate
function in preparation to extend irq_setup_virq to handle multiple
irqs and rename it for use by interrupt controller drivers.  The new
function will be used by irq_setup_virq() in its error path.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>

The revmap type should be linear for irq_domain_add_linear function.
Signed-off-by: NDong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

A large proportion of interrupt controllers that support legacy mappings
do so because non-DT systems need to use fixed IRQ numbers when registering
devices via buses but can otherwise use a linear mapping. The interrupt
controller itself typically is not affected by the mapping used and best
practice is to use a linear mapping where possible so drivers frequently
select at runtime depending on if a legacy range has been allocated to
them.

Standardise this behaviour by providing irq_domain_register_simple() which
will allocate a linear mapping unless a positive first_irq is provided in
which case it will fall back to a legacy mapping. This helps make best
practice for irq_domain adoption clearer.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The pattern (np ? np->full_name : "<none>") is rather common in the
kernel, but can also make for quite long lines.  This patch adds a new
inline function, of_node_full_name() so that the test for a valid node
pointer doesn't need to be open coded at all call sites.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

There isn't a really compelling reason to force ->map to be populated,
so allow it to be left unset.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>

Where irq_domain_associate() is called in irq_create_mapping, there is
no need to test for IRQ_DOMAIN_MAP_LEGACY because it is already tested
for earlier in the routine.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>

While common irqdesc allocation is node aware, the irqdomain code is not.

Presently we observe a number of regressions/inconsistencies on
NUMA-capable platforms:

- Platforms using irqdomains with legacy mappings, where the
  irq_descs are allocated node-local and the irqdomain data
  structure is not.

- Drivers implementing irqdomains will lose node locality
  regardless of the underlying struct device's node id.

This plugs in NUMA node id proliferation across the various allocation
callsites by way of_node_to_nid() node lookup. While of_node_to_nid()
does the right thing for OF-capable platforms it doesn't presently handle
the non-DT case. This is trivially dealt with by simply wraping in to
numa_node_id() unconditionally.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The pattern (np ? np->full_name : "<none>") is rather common in the
kernel, but can also make for quite long lines.  This patch adds a new
inline function, of_node_full_name() so that the test for a valid node
pointer doesn't need to be open coded at all call sites.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

Use the module-wide pr_fmt() mechanism rather than open-coding "genirq: "
everywhere.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

All invocations of chip->irq_set_affinity() are doing the same return
value checks. Let them all use a common function.

[ tglx: removed the silly likely while at it ]
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Keping Chen <chenkeping@huawei.com>
Link: http://lkml.kernel.org/r/1333120296-13563-3-git-send-email-jiang.liu@huawei.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Every interrupt which is an active wakeup source needs the ability to
abort suspend if there is a pending irq. Right now only edge and level
irqs can do that.

            |
       +---------+
       |   INTC  |
       +---------+
               | GPIO_IRQ
            +------------+
            |  gpio-exp  |
            +------------+
              |        |
         GPIO0_IRQ  GPIO1_IRQ

In the above diagram, gpio expander has irq number GPIO_IRQ, it is
connected with two sub GPIO pins, GPIO0 and GPIO1.

During suspend, we set IRQF_NO_SUSPEND for GPIO_IRQ so that gpio
expander driver can handle the sub irq GPIO0_IRQ and GPIO1_IRQ, and
these two irqs themselves can further be handled by simple or nested
irq in some drivers(typically gpio and mfd driver). If they are used
as wakeup sources during suspend, we want them to be able to abort
suspend too.

Setting IRQS_PENDING flag in handle_nested_irq() and handle_simple_irq()
when the irq is disabled allows check_wakeup_irqs() to identify such
irqs as source for aborting suspend.
Signed-off-by: NNing Jiang <ning.n.jiang@gmail.com>
Cc: rjw@sisk.pl
Link: http://lkml.kernel.org/r/CAH3Oq6T905%2B3fkF43NAMMFvJvq7dsk_so6T2vQ8ZJrA5xiU3YA@mail.gmail.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

exit_irq_thread() and task->irq_thread are needed to handle the unexpected
(and unlikely) exit of irq-thread.

We can use task_work instead and make this all private to
kernel/irq/manage.c, cleanup plus micro-optimization.

1. rename exit_irq_thread() to irq_thread_dtor(), make it
   static, and move it up before irq_thread().

2. change irq_thread() to do task_work_add(irq_thread_dtor)
   at the start and task_work_cancel() before return.

   tracehook_notify_resume() can never play with kthreads,
   only do_exit()->exit_task_work() can call the callback
   and this is what we want.

3. remove task_struct->irq_thread and the special hook
   in do_exit().
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Smith <dsmith@redhat.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

As it's only user (UML) does no longer need it we can get
rid of it.
Signed-off-by: NRichard Weinberger <richard@nod.at>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Convert to pr_fmt before things start to get out of hand and some
janitors start getting overly excited.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Presently irq_domain_simple_map() isn't labelled as static, but there's
no definition for it in the public irqdomain header either. At present
all in-tree ->map users have meaningful work to do, and all others are
using irq_domain_simple_ops directly. Make it static for now, as it can
always be exported and added to the public API later.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

modules making use of irq domains at the very least need access to the
add/remove/lookup routines, though there's nothing preventing them from
using the remainder of the public API, either.

The current set of exports seem primarily geared at DT-enabled platforms
using DT-backed IRQ domains, where many of the API accesses are hidden
away in OF code. The non-DT cases need to do most of this on their own.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Now that IRQ domains are being used by modules it's necessary to support
removing them, too. This adds a new irq_domain_remove() routine for doing
the bulk of the heavy lifting. It's left as an exercise to the caller to
ensure all mappings have been appropriatey disposed of before attempting
to remove the domain.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Export handle_edge_irq() and irq_to_desc() to modules to allow them to
do things such as

	__irq_set_handler_locked(...., handle_edge_irq);

This fixes

	ERROR: "handle_edge_irq" [drivers/gpio/gpio-pch.ko] undefined!
	ERROR: "irq_to_desc" [drivers/gpio/gpio-pch.ko] undefined!

when gpio-pch is being built as a module.

This was introduced by commit df9541a6 ("gpio: pch9: Use proper flow
type handlers") that added

	__irq_set_handler_locked(d->irq, handle_edge_irq);

but handle_edge_irq() was not exported for modules (and inlined
__irq_set_handler_locked() requires irq_to_desc() exported as well)
Signed-off-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If an wakeup interrupt has been disabled before the suspend code
disables all interrupts then we have to ignore the pending flag.

Otherwise we would abort suspend over and over as nothing clears the
pending flag because the interrupt is disabled.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: NeilBrown <neilb@suse.de>

Level triggered interrupts do not cause IRQS_PENDING to be set when
they fire while "disabled" as the 'pending' state is always present in
the level - they automatically refire where re-enabled.

However the IRQS_PENDING flag is also used to abort a suspend cycle -
if any 'is_wakeup_set' interrupt is PENDING, check_wakeup_irqs() will
cause suspend to abort. Without IRQS_PENDING, suspend won't abort.

Consequently, level-triggered interrupts that fire during the 'noirq'
phase of suspend do not currently abort suspend.

So set IRQS_PENDING even for level triggered interrupts, and make sure
to clear the flag in check_irq_resend.

[ Changelog by courtesy of Neil ]
Tested-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The file kernel/irq/debug.h temporarily defines P, PS, PD
and then undefines them.  However these names aren't really
"internal" enough, and collide with other more legit users
such as the ones in the xtensa arch, causing:

In file included from kernel/irq/internals.h:58:0,
                 from kernel/irq/irqdesc.c:18:
kernel/irq/debug.h:8:0: warning: "PS" redefined [enabled by default]
arch/xtensa/include/asm/regs.h:59:0: note: this is the location of the previous definition

Add a handful of underscores to do a better job of hiding these
temporary macros.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

We require that shared interrupts agree on a few flag settings. Right
now we silently return with an error code without giving any hint why
we reject it.

Make the printout unconditionally and actually useful by printing the
flags of the new and the already registered action.

Convert all printks to pr_* and use a proper prefix while at it.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Requesting a threaded interrupt without a primary handler and without
IRQF_ONESHOT set is dangerous.

The core will use the default primary handler for it, which merily
wakes the thread. For a level type interrupt this results in an
interrupt storm, because the interrupt line is reenabled after the
primary handler runs. The device has still the line asserted, which
brings us back into the primary handler.

While this works for edge type interrupts, we play it safe and reject
unconditionally because we can't say for sure which type this
interrupt really has. The type flags are unreliable as the underlying
chip implementation can override them. And we cannot assume that
developers using that interface know what they are doing.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

sizeof(void*) returns an unsigned long, but it was being used as a width parameter to a "%-*s" format string which requires an int.  On 64 bit platforms this causes a type mismatch:

    linux/kernel/irq/irqdomain.c:575: warning: field width should have type
    'int', but argument 6 has type 'long unsigned int'

This change casts the size to an int so printf gets the right data type.
Reported-by: NAndreas Schwab <schwab@linux-m68k.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>

This patch replaces the old global setting of irq_virq_count that is only
used by the NOMAP mapping and instead uses a revmap_data property so that
the maximum NOMAP allocation can be set per NOMAP irq_domain.

There is exactly one user of irq_virq_count in-tree right now: PS3.
Also, irq_virq_count is only useful for the NOMAP mapping.  So,
instead of having a single global irq_virq_count values, this change
drops it entirely and added a max_irq argument to irq_domain_add_nomap().
That makes it a property of an individual nomap irq domain instead of
a global system settting.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Tested-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>

This patch fixes the irq_domain_mapping debugfs output to pad pointer
values with leading zeros so that pointer values are displayed
correctly.  Otherwise you get output similar to "0x 5e0000000000000".
Also, when the irq_domain is set to 'null'
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>

The actual name of the irq_domain mapping debugfs file is
"irq_domain_mapping" not "virq_mapping".
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

In commit 4bbdd45a (irq_domain/powerpc: eliminate irq_map; use
irq_alloc_desc() instead) code was added that ignores error returns
from irq_alloc_desc_from() by (silently) casting the return value to
unsigned.  The negitive value error return now suddenly looks like a
valid irq number.

Commits cc79ca69 (irq_domain: Move irq_domain code from powerpc to
kernel/irq) and 1bc04f2c (irq_domain: Add support for base irq and
hwirq in legacy mappings) move this code to its current location in
irqdomain.c

The result of all of this is a null pointer dereference OOPS if one of
the error cases is hit.

The fix: Don't cast away the negativeness of the return value and then
check for errors.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Acked-by: NRob Herring <rob.herring@calxeda.com>
[grant.likely: dropped addition of new 'irq' variable]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

irq_move_masked_irq() checks the return code of
chip->irq_set_affinity() only for 0, but IRQ_SET_MASK_OK_NOCOPY is
also a valid return code, which is there to avoid a redundant copy of
the cpumask. But in case of IRQ_SET_MASK_OK_NOCOPY we not only avoid
the redundant copy, we also fail to adjust the thread affinity of an
eventually threaded interrupt handler.

Handle IRQ_SET_MASK_OK (==0) and IRQ_SET_MASK_OK_NOCOPY(==1) return
values correctly by checking the valid return values seperately.
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Keping Chen <chenkeping@huawei.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1333120296-13563-2-git-send-email-jiang.liu@huawei.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The debugfs code is really generic for all platforms.  This patch removes the
powerpc-specific directory reference and makes it available to all
architectures.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

We respect node affinity of devices already in the irq descriptor
allocation, but we ignore it for the initial interrupt affinity
setup, so the interrupt might be routed to a different node.

Restrict the default affinity mask to the node on which the irq
descriptor is allocated.

[ tglx: Massaged changelog ]
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/1332788538-17425-1-git-send-email-prarit@redhat.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The only place irq_finalize_oneshot() is called with force parameter set
is the threaded handler error exit path. But IRQTF_RUNTHREAD is dropped
at this point and irq_wake_thread() is not going to set it again,
since PF_EXITING is set for this thread already. So irq_finalize_oneshot()
will drop the threads bit in threads_oneshot anyway and hence the force
parameter is superfluous.
Signed-off-by: NAlexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120321162234.GP24806@dhcp-26-207.brq.redhat.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>