Commit Graph

112844 Commits

Author SHA1 Message Date
Hans Verkuil
55028695c3 media: vb2: drop VB2_BUF_STATE_PREPARED, use bool prepared/synced instead
The PREPARED state becomes a problem with the request API: a buffer
could be PREPARED but dequeued, or PREPARED and in state IN_REQUEST.

PREPARED is really not a state as such, but more a property of the
buffer. So make new 'prepared' and 'synced' bools instead to remember
whether the buffer is prepared and/or synced or not.

V4L2_BUF_FLAG_PREPARED is only set if the buffer is both synced and
prepared and in the DEQUEUED state.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:16:10 -04:00
Hans Verkuil
db6e8d57e2 media: vb2: store userspace data in vb2_v4l2_buffer
The userspace-provided plane data needs to be stored in
vb2_v4l2_buffer. Currently this information is applied by
__fill_vb2_buffer() which is called by the core prepare_buf
and qbuf functions, but when using requests these functions
aren't called yet since the buffer won't be prepared until
the media request is actually queued.

In the meantime this information has to be stored somewhere
and vb2_v4l2_buffer is a good place for it.

The __fill_vb2_buffer callback now just copies the relevant
information from vb2_v4l2_buffer into the planes array.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:14:44 -04:00
Hans Verkuil
5f611d74c2 media: v4l2-ctrls: add v4l2_ctrl_request_hdl_find/put/ctrl_find functions
If a driver needs to find/inspect the controls set in a request then
it can use these functions.

E.g. to check if a required control is set in a request use this in the
req_validate() implementation:

	int res = -EINVAL;

	hdl = v4l2_ctrl_request_hdl_find(req, parent_hdl);
	if (hdl) {
		if (v4l2_ctrl_request_hdl_ctrl_find(hdl, ctrl_id))
			res = 0;
		v4l2_ctrl_request_hdl_put(hdl);
	}
	return res;

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:13:09 -04:00
Hans Verkuil
c41e9cff70 media: v4l2-ctrls: support g/s_ext_ctrls for requests
The v4l2_g/s_ext_ctrls functions now support control handlers that
represent requests.

The v4l2_ctrls_find_req_obj() function is responsible for finding the
request from the fd.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:12:29 -04:00
Hans Verkuil
6fa6f831f0 media: v4l2-ctrls: add core request support
Integrate the request support. This adds the v4l2_ctrl_request_complete
and v4l2_ctrl_request_setup functions to complete a request and (as a
helper function) to apply a request to the hardware.

It takes care of queuing requests and correctly chaining control values
in the request queue.

Note that when a request is marked completed it will copy control values
to the internal request state. This can be optimized in the future since
this is sub-optimal when dealing with large compound and/or array controls.

For the initial 'stateless codec' use-case the current implementation is
sufficient.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:12:01 -04:00
Hans Verkuil
52beeddb68 media: v4l2-ctrls: prepare internal structs for request API
Embed and initialize a media_request_object in struct v4l2_ctrl_handler.

Add a p_req field to struct v4l2_ctrl_ref that will store the
request value.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:10:25 -04:00
Hans Verkuil
da1b1aeac1 media: v4l2-ctrls: v4l2_ctrl_add_handler: add from_other_dev
Add a 'bool from_other_dev' argument: set to true if the two
handlers refer to different devices (e.g. it is true when
inheriting controls from a subdev into a main v4l2 bridge
driver).

This will be used later when implementing support for the
request API since we need to skip such controls.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:09:34 -04:00
Alexandre Courbot
f23317adf6 media: videodev2.h: add request_fd field to v4l2_ext_controls
If 'which' is V4L2_CTRL_WHICH_REQUEST_VAL, then the 'request_fd' field
can be used to specify a request for the G/S/TRY_EXT_CTRLS ioctls.

Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:08:55 -04:00
Hans Verkuil
93a9d9008d media: v4l2-device.h: add v4l2_device_supports_requests() helper
Add a simple helper function that tests if the driver supports
the request API.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:07:26 -04:00
Hans Verkuil
0ca0e8442d media: media-request: add media_request_object_find
Add media_request_object_find to find a request object inside a
request based on ops and priv values.

Objects of the same type (vb2 buffer, control handler) will have
the same ops value. And objects that refer to the same 'parent'
object (e.g. the v4l2_ctrl_handler that has the current driver
state) will have the same priv value.

The caller has to call media_request_object_put() for the returned
object since this function increments the refcount.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:07:08 -04:00
Hans Verkuil
be9d6d4b0b media: media-request: add media_request_get_by_fd
Add media_request_get_by_fd() to find a request based on the file
descriptor.

The caller has to call media_request_put() for the returned
request since this function increments the refcount.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:06:24 -04:00
Hans Verkuil
10905d70d7 media: media-request: implement media requests
Add initial media request support:

1) Add MEDIA_IOC_REQUEST_ALLOC ioctl support to media-device.c
2) Add struct media_request to store request objects.
3) Add struct media_request_object to represent a request object.
4) Add MEDIA_REQUEST_IOC_QUEUE/REINIT ioctl support.

Basic lifecycle: the application allocates a request, adds
objects to it, queues the request, polls until it is completed
and can then read the final values of the objects at the time
of completion. When it closes the file descriptor the request
memory will be freed (actually, when the last user of that request
releases the request).

Drivers will bind an object to a request (the 'adds objects to it'
phase), when MEDIA_REQUEST_IOC_QUEUE is called the request is
validated (req_validate op), then queued (the req_queue op).

When done with an object it can either be unbound from the request
(e.g. when the driver has finished with a vb2 buffer) or marked as
completed (e.g. for controls associated with a buffer). When all
objects in the request are completed (or unbound), then the request
fd will signal an exception (poll).

Co-developed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Co-developed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Co-developed-by: Alexandre Courbot <acourbot@chromium.org>

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:04:51 -04:00
Hans Verkuil
66431c0bab media: uapi/linux/media.h: add request API
Define the public request API.

This adds the new MEDIA_IOC_REQUEST_ALLOC ioctl to allocate a request
and two ioctls that operate on a request in order to queue the
contents of the request to the driver and to re-initialize the
request.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:04:23 -04:00
Kuninori Morimoto
868cdb4690 ASoC: simple-card-util: support snd_soc_dai_link_component style for platform
Current ASoC is supporting snd_soc_dai_link_component for binding,
it is more useful than current legacy style.
Currently only codec is supporting it as multicodec (= codecs).
CPU will support multi style in the future.
We want to have it on Platform too in the future.

If all Codec/CPU/Platform are replaced into snd_soc_dai_link_component
style, we can remove legacy complex style.
This patch supports snd_soc_dai_link_component style
for simple-card-util for platform.

[current]
struct snd_soc_dai_link {
	...
	*cpu_name;
	*cpu_of_node;
	*cpu_dai_name;

	*codec_name;
	*codec_of_node;
	*codec_dai_name;
	*codecs;
	num_codecs;

	*platform_name;
	*platform_of_node;
	...
}

[in the future]
struct snd_soc_dai_link {
	...
	*cpus
	num_cpus;

	*codecs;
	num_codecs;

	*platform;
	...
}

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-31 15:58:43 +01:00
Kuninori Morimoto
daecf46ee0 ASoC: soc-core: use snd_soc_dai_link_component for platform
Current struct snd_soc_dai_link is supporting multicodec,
and it is supporting legacy style of
	codec_name
	codec_of_node
	code_dai_name
This is handled as single entry of multicodec.

We don't have multicpu support yet, but in the future we will.
In such case, we can use snd_soc_dai_link_component for both
cpu/codec. Then the code will be more simple and readble.

As next step, we want to use it for platform, too.
This patch adds snd_soc_dai_link_component style for platform.
We might have multiplatform support in the future, but we
don't know yet. To avoid un-known issue / complex code,
this patch supports just single-platform as 1st step.

If we could use snd_soc_dai_link_component for all CPU/Codec/Platform,
we will switch to new style, and remove legacy code.
This is prepare for it.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-31 15:58:39 +01:00
Kuninori Morimoto
e664de680b ASoC: simple_card_utils: support snd_soc_dai_link_component style for codec
Current ASoC is supporting snd_soc_dai_link_component for binding,
it is more useful than current legacy style.
Currently only codec is supporting it as multicodec (= codecs).
CPU will support multi style in the future.
We want to have it on Platform too in the future.

If all Codec/CPU/Platform are replaced into snd_soc_dai_link_component
style, we can remove legacy complex style.
This patch supports snd_soc_dai_link_component style
for simple_card_utils for codec.

[current]
struct snd_soc_dai_link {
	...
	*cpu_name;
	*cpu_of_node;
	*cpu_dai_name;

	*codec_name;
	*codec_of_node;
	*codec_dai_name;
	*codecs;
	num_codecs;

	*platform_name;
	*platform_of_node;
	...
}

[in the future]
struct snd_soc_dai_link {
	...
	*cpus
	num_cpus;

	*codecs;
	num_codecs;

	*platform;
	...
}

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-31 15:58:07 +01:00
Philipp Zabel
ef394f3fbe regulator: da9063: fix DT probing with constraints
Commit 1c892e38ce ("regulator: da9063: Handle less LDOs on DA9063L")
reordered the da9063_regulator_info[] array, but not the DA9063_ID_*
regulator ids and not the da9063_matches[] array, because ids are used
as indices in the array initializer. This mismatch between regulator id
and da9063_regulator_info[] array index causes the driver probe to fail
because constraints from DT are not applied to the correct regulator:

  da9063 0-0058: Device detected (chip-ID: 0x61, var-ID: 0x50)
  DA9063_BMEM: Bringing 900000uV into 3300000-3300000uV
  DA9063_LDO9: Bringing 3300000uV into 2500000-2500000uV
  DA9063_LDO1: Bringing 900000uV into 3300000-3300000uV
  DA9063_LDO1: failed to apply 3300000-3300000uV constraint(-22)

This patch reorders the DA9063_ID_* as apparently intended, and with
them the entries in the da90630_matches[] array.

Fixes: 1c892e38ce ("regulator: da9063: Handle less LDOs on DA9063L")
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-31 15:55:54 +01:00
Jose Abreu
87f9ed85d0 media: v4l2-dv-timings: Introduce v4l2_calc_timeperframe helper
A new helper function was introduced to facilitate the calculation
of time per frame value whenever we have access to the full
v4l2_dv_timings structure.

This should be used only for receivers and only when there is
enough accuracy in the measured pixel clock value as well as in
the horizontal/vertical values.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 10:02:45 -04:00
Jose Abreu
f992cee5ef media: videodev2.h: Add new DV flag CAN_DETECT_REDUCED_FPS
Add a new flag to UAPI for DV timings which, whenever set,
indicates that hardware can detect the difference between
regular FPS and 1000/1001 FPS.

This is specific to HDMI receivers. Also, it is only valid
when V4L2_DV_FL_CAN_REDUCE_FPS is set.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 09:32:02 -04:00
Rob Herring
0413bedabc of: Add device_type access helper functions
In preparation to remove direct access to device_node.type, add
of_node_is_type() and of_node_get_device_type() helpers to check and
retrieve the device type.

Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2018-08-31 08:30:42 -04:00
Amit Nischal
f40c467523 dt-bindings: clock: Introduce QCOM Camera clock bindings
Add device tree bindings for camera clock controller for
Qualcomm Technology Inc's SDM845 SoCs.

Signed-off-by: Amit Nischal <anischal@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2018-08-30 18:26:45 -07:00
Paul E. McKenney
b56ada1209 Merge branches 'doc.2018.08.30a', 'dynticks.2018.08.30b', 'srcu.2018.08.30b' and 'torture.2018.08.29a' into HEAD
doc.2018.08.30a: Documentation updates
dynticks.2018.08.30b: RCU flavor consolidation updates and cleanups
srcu.2018.08.30b: SRCU updates
torture.2018.08.29a: Torture-test updates
2018-08-30 16:12:53 -07:00
Paul E. McKenney
4e6ea4ef56 srcu: Make early-boot call_srcu() reuse workqueue lists
Allocating a list_head structure that is almost never used, and, when
used, is used only during early boot (rcu_init() and earlier), is a bit
wasteful.  This commit therefore eliminates that list_head in favor of
the one in the work_struct structure.  This is safe because the work_struct
structure cannot be used until after rcu_init() returns.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-30 16:10:49 -07:00
Paul E. McKenney
e0fcba9ac0 srcu: Make call_srcu() available during very early boot
Event tracing is moving to SRCU in order to take advantage of the fact
that SRCU may be safely used from idle and even offline CPUs.  However,
event tracing can invoke call_srcu() very early in the boot process,
even before workqueue_init_early() is invoked (let alone rcu_init()).
Therefore, call_srcu()'s attempts to queue work fail miserably.

This commit therefore detects this situation, and refrains from attempting
to queue work before rcu_init() time, but does everything else that it
would have done, and in addition, adds the srcu_struct to a global list.
The rcu_init() function now invokes a new srcu_init() function, which
is empty if CONFIG_SRCU=n.  Otherwise, srcu_init() queues work for
each srcu_struct on the list.  This all happens early enough in boot
that there is but a single CPU with interrupts disabled, which allows
synchronization to be dispensed with.

Of course, the queued work won't actually be invoked until after
workqueue_init() is invoked, which happens shortly after the scheduler
is up and running.  This means that although call_srcu() may be invoked
any time after per-CPU variables have been set up, there is still a very
narrow window when synchronize_srcu() won't work, and this window
extends from the time that the scheduler starts until the time that
workqueue_init() returns.  This can be fixed in a manner similar to
the fix for synchronize_rcu_expedited() and friends, but until someone
actually needs to use synchronize_srcu() during this window, this fix
is added churn for no benefit.

Finally, note that Tree SRCU's new srcu_init() function invokes
queue_work() rather than the queue_delayed_work() function that is
invoked post-boot.  The reason is that queue_delayed_work() will (as you
would expect) post a timer, and timers have not yet been initialized.
So use of queue_work() avoids the complaints about use of uninitialized
spinlocks that would otherwise result.  Besides, some delay is already
provide by the aforementioned fact that the queued work won't actually
be invoked until after the scheduler is up and running.

Requested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-30 16:10:19 -07:00
Paul E. McKenney
31ab604bf3 rcu: Remove unused rcu_dynticks_snap() from Tiny RCU
The rcu_dynticks_snap() function is defined in include/linux/rcutiny.h,
but is no longer used by Tiny RCU.  This commit therefore removes it.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:46 -07:00
Paul E. McKenney
74de6960c9 rcu: Provide functions for determining if call_rcu() has been invoked
This commit adds rcu_head_init() and rcu_head_after_call_rcu() functions
to help RCU users detect when another CPU has passed the specified
rcu_head structure and function to call_rcu().  The rcu_head_init()
should be invoked before making the structure visible to RCU readers,
and then the rcu_head_after_call_rcu() may be invoked from within
an RCU read-side critical section on an rcu_head structure that
was obtained during a traversal of the data structure in question.
The rcu_head_after_call_rcu() function will return true if the rcu_head
structure has already been passed (with the specified function) to
call_rcu(), otherwise it will return false.

If rcu_head_init() has not been invoked on the rcu_head structure
or if the rcu_head (AKA callback) has already been invoked, then
rcu_head_after_call_rcu() will do WARN_ON_ONCE().

Reported-by: NeilBrown <neilb@suse.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Apply neilb naming feedback. ]
2018-08-30 16:03:42 -07:00
Paul E. McKenney
7e28c5af4e rcu: Eliminate ->rcu_qs_ctr from the rcu_dynticks structure
The ->rcu_qs_ctr counter was intended to allow providing a lightweight
report of a quiescent state to all RCU flavors.  But now that there is
only one flavor of RCU in any one running kernel, there is no point in
having this feature.  This commit therefore removes the ->rcu_qs_ctr
field from the rcu_dynticks structure and the ->rcu_qs_ctr_snap field
from the rcu_data structure.  This results in the "rqc" option to the
rcu_fqs trace event no longer being used, so this commit also removes the
"rqc" description from the header comment.

While in the neighborhood, this commit also causes the forward-progress
request .rcu_need_heavy_qs be set one jiffies_till_sched_qs interval
later in the grace period than the first setting of .rcu_urgent_qs.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:42 -07:00
Paul E. McKenney
dd46a7882c rcu: Inline _rcu_barrier() into its sole remaining caller
Because rcu_barrier() is a one-line wrapper function for _rcu_barrier()
and because nothing else calls _rcu_barrier(), this commit inlines
_rcu_barrier() into rcu_barrier().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:39 -07:00
Paul E. McKenney
395a2f097e rcu: Define rcu_all_qs() only in !PREEMPT builds
Now that rcu_all_qs() is used only in !PREEMPT builds, move it to
tree_plugin.h so that it is defined only in those builds.  This in
turn means that rcu_momentary_dyntick_idle() is only used in !PREEMPT
builds, but it is simply marked __maybe_unused in order to keep it
near the rest of the dyntick-idle code.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:37 -07:00
Paul E. McKenney
4d232dfe1d rcu: Remove !PREEMPT code from rcu_note_voluntary_context_switch()
Because RCU-tasks exists only in PREEMPT kernels and because RCU-sched
no longer exists in PREEMPT kernels, it is no longer necessary for the
rcu_note_voluntary_context_switch() macro to do anything for !PREEMPT
kernels.  This commit therefore removes !PREEMPT-related code from
this macro, namely, the rcu_all_qs().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:36 -07:00
Paul E. McKenney
df8561a0d7 rcu: Clean up flavor-related definitions and comments in rcupdate_wait.h
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:32 -07:00
Paul E. McKenney
aff5f0369e rcu: Clean up flavor-related definitions and comments in rculist.h
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:31 -07:00
Paul E. McKenney
2bd8b1a2af rcu: Clean up flavor-related definitions and comments in rcupdate.h
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:31 -07:00
Paul E. McKenney
a8bb74acd8 rcu: Consolidate RCU-sched update-side function definitions
This commit saves a few lines by consolidating the RCU-sched function
definitions at the end of include/linux/rcupdate.h.  This consolidation
also makes it easier to remove them all when the time comes.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:26 -07:00
Paul E. McKenney
4c7e9c1434 rcu: Consolidate RCU-bh update-side function definitions
This commit saves a few lines by consolidating the RCU-bh function
definitions at the end of include/linux/rcupdate.h.  This consolidation
also makes it easier to remove them all when the time comes.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:25 -07:00
Paul E. McKenney
709fdce754 rcu: Express Tiny RCU updates in terms of RCU rather than RCU-sched
This commit renames Tiny RCU functions so that the lowest level of
functionality is RCU (e.g., synchronize_rcu()) rather than RCU-sched
(e.g., synchronize_sched()).  This provides greater naming compatibility
with Tree RCU, which will in turn permit more LoC removal once
the RCU-sched and RCU-bh update-side API is removed.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Fix Tiny call_rcu()'s EXPORT_SYMBOL() in response to a bug
  report from kbuild test robot. ]
2018-08-30 16:02:46 -07:00
Paul E. McKenney
45975c7d21 rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds
Now that RCU-preempt knows about preemption disabling, its implementation
of synchronize_rcu() works for synchronize_sched(), and likewise for the
other RCU-sched update-side API members.  This commit therefore confines
the RCU-sched update-side code to CONFIG_PREEMPT=n builds, and defines
RCU-sched's update-side API members in terms of those of RCU-preempt.

This means that any given build of the Linux kernel has only one
update-side flavor of RCU, namely RCU-preempt for CONFIG_PREEMPT=y builds
and RCU-sched for CONFIG_PREEMPT=n builds.  This in turn means that kernels
built with CONFIG_RCU_NOCB_CPU=y have only one rcuo kthread per CPU.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
2018-08-30 16:02:45 -07:00
Paul E. McKenney
82fcecfa81 rcu: Update comments and help text for no more RCU-bh updaters
This commit updates comments and help text to account for the fact that
RCU-bh update-side functions are now simple wrappers for their RCU or
RCU-sched counterparts.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:02:42 -07:00
Paul E. McKenney
65cfe3583b rcu: Define RCU-bh update API in terms of RCU
Now that the main RCU API knows about softirq disabling and softirq's
quiescent states, the RCU-bh update code can be dispensed with.
This commit therefore removes the RCU-bh update-side implementation and
defines RCU-bh's update-side API in terms of that of either RCU-preempt or
RCU-sched, depending on the setting of the CONFIG_PREEMPT Kconfig option.

In kernels built with CONFIG_RCU_NOCB_CPU=y this has the knock-on effect
of reducing by one the number of rcuo kthreads per CPU.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:02:40 -07:00
Paul E. McKenney
d28139c4e9 rcu: Apply RCU-bh QSes to RCU-sched and RCU-preempt when safe
One necessary step towards consolidating the three flavors of RCU is to
make sure that the resulting consolidated "one flavor to rule them all"
correctly handles networking denial-of-service attacks.  One thing that
allows RCU-bh to do so is that __do_softirq() invokes rcu_bh_qs() every
so often, and so something similar has to happen for consolidated RCU.

This must be done carefully.  For example, if a preemption-disabled
region of code takes an interrupt which does softirq processing before
returning, consolidated RCU must ignore the resulting rcu_bh_qs()
invocations -- preemption is still disabled, and that means an RCU
reader for the consolidated flavor.

This commit therefore creates a new rcu_softirq_qs() that is called only
from the ksoftirqd task, thus avoiding the interrupted-a-preempted-region
problem.  This new rcu_softirq_qs() function invokes rcu_sched_qs(),
rcu_preempt_qs(), and rcu_preempt_deferred_qs().  The latter call handles
any deferred quiescent states.

Note that __do_softirq() still invokes rcu_bh_qs().  It will continue to
do so until a later stage of cleanup when the RCU-bh flavor is removed.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Fix !SMP issue located by kbuild test robot. ]
2018-08-30 16:02:38 -07:00
Paul E. McKenney
fcc878e4df rcu: Remove now-unused ->b.exp_need_qs field from the rcu_special union
The ->b.exp_need_qs field is now set only to false, so this commit
removes it.  The job this field used to do is now done by the rcu_data
structure's ->deferred_qs field, which is a consequence of a better
split between task-based (the rcu_node structure's ->exp_tasks field) and
CPU-based (the aforementioned rcu_data structure's ->deferred_qs field)
tracking of quiescent states for RCU-preempt expedited grace periods.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:02:36 -07:00
Paul E. McKenney
3e31009898 rcu: Defer reporting RCU-preempt quiescent states when disabled
This commit defers reporting of RCU-preempt quiescent states at
rcu_read_unlock_special() time when any of interrupts, softirq, or
preemption are disabled.  These deferred quiescent states are reported
at a later RCU_SOFTIRQ, context switch, idle entry, or CPU-hotplug
offline operation.  Of course, if another RCU read-side critical
section has started in the meantime, the reporting of the quiescent
state will be further deferred.

This also means that disabling preemption, interrupts, and/or
softirqs will act as an RCU-preempt read-side critical section.
This is enforced by checking preempt_count() as needed.

Some special cases must be handled on an ad-hoc basis, for example,
context switch is a quiescent state even though both the scheduler and
do_exit() disable preemption.  In these cases, additional calls to
rcu_preempt_deferred_qs() override the preemption disabling.  Similar
logic overrides disabled interrupts in rcu_preempt_check_callbacks()
because in this case the quiescent state happened just before the
corresponding scheduling-clock interrupt.

In theory, this change lifts a long-standing restriction that required
that if interrupts were disabled across a call to rcu_read_unlock()
that the matching rcu_read_lock() also be contained within that
interrupts-disabled region of code.  Because the reporting of the
corresponding RCU-preempt quiescent state is now deferred until
after interrupts have been enabled, it is no longer possible for this
situation to result in deadlocks involving the scheduler's runqueue and
priority-inheritance locks.  This may allow some code simplification that
might reduce interrupt latency a bit.  Unfortunately, in practice this
would also defer deboosting a low-priority task that had been subjected
to RCU priority boosting, so real-time-response considerations might
well force this restriction to remain in place.

Because RCU-preempt grace periods are now blocked not only by RCU
read-side critical sections, but also by disabling of interrupts,
preemption, and softirqs, it will be possible to eliminate RCU-bh and
RCU-sched in favor of RCU-preempt in CONFIG_PREEMPT=y kernels.  This may
require some additional plumbing to provide the network denial-of-service
guarantees that have been traditionally provided by RCU-bh.  Once these
are in place, CONFIG_PREEMPT=n kernels will be able to fold RCU-bh
into RCU-sched.  This would mean that all kernels would have but
one flavor of RCU, which would open the door to significant code
cleanup.

Moving to a single flavor of RCU would also have the beneficial effect
of reducing the NOCB kthreads by at least a factor of two.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Apply rcu_read_unlock_special() preempt_count() feedback
  from Joel Fernandes. ]
[ paulmck: Adjust rcu_eqs_enter() call to rcu_preempt_deferred_qs() in
  response to bug reports from kbuild test robot. ]
[ paulmck: Fix bug located by kbuild test robot involving recursion
  via rcu_preempt_deferred_qs(). ]
2018-08-30 16:02:34 -07:00
Wolfram Sang
82fe39a6bc i2c: refactor function to release a DMA safe buffer
a) rename to 'put' instead of 'release' to match 'get' when obtaining
   the buffer
b) change the argument order to have the buffer as first argument
c) add a new argument telling the function if the message was
   transferred. This allows the function to be used also in cases
   where setting up DMA failed, so the buffer needs to be freed without
   syncing to the message buffer.

Also convert the only user.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-30 23:13:15 +02:00
Harshitha Ramamurthy
a4e0109a19 virtchnl: use u8 type for a field in the virtchnl_filter struct
The virtchnl_filter struct has a field called field_flags. A previous
commit mistakenly had the type to be a __u8. What we want is for the
field to be an unsigned 8 bit value, so let's just use the existing
kernel type u8 for that.

Signed-off-by: Harshitha Ramamurthy <harshitha.ramamurthy@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-08-30 13:53:04 -07:00
Rob Herring
f42b0e18f2 of: add node name compare helper functions
In preparation to remove device_node.name pointer, add helper functions
for node name comparisons which are a common pattern throughout the kernel.

Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2018-08-30 13:53:05 -05:00
Amir Goldstein
45cd0faae3 vfs: add the fadvise() file operation
This is going to be used by overlayfs and possibly useful
for other filesystems.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-08-30 17:08:35 +02:00
Takashi Iwai
56e91b1268 Merge tag 'hda-codec-h-move' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next
ALSA: Move hda_codec.h to include/sound

For easier sharing with ASoC.
2018-08-30 16:55:38 +02:00
Pierre-Louis Bossart
be57bfffb7 ALSA: hda: move hda_codec.h to include/sound
As suggested by Takashi, move this header file to make it easier
to include from e.g. the Intel Skylake driver in follow-up patches

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-30 15:45:10 +01:00
Marc Zyngier
755a8bf557 arm/arm64: smccc-1.1: Handle function result as parameters
If someone has the silly idea to write something along those lines:

	extern u64 foo(void);

	void bar(struct arm_smccc_res *res)
	{
		arm_smccc_1_1_smc(0xbad, foo(), res);
	}

they are in for a surprise, as this gets compiled as:

	0000000000000588 <bar>:
	 588:   a9be7bfd        stp     x29, x30, [sp, #-32]!
	 58c:   910003fd        mov     x29, sp
	 590:   f9000bf3        str     x19, [sp, #16]
	 594:   aa0003f3        mov     x19, x0
	 598:   aa1e03e0        mov     x0, x30
	 59c:   94000000        bl      0 <_mcount>
	 5a0:   94000000        bl      0 <foo>
	 5a4:   aa0003e1        mov     x1, x0
	 5a8:   d4000003        smc     #0x0
	 5ac:   b4000073        cbz     x19, 5b8 <bar+0x30>
	 5b0:   a9000660        stp     x0, x1, [x19]
	 5b4:   a9010e62        stp     x2, x3, [x19, #16]
	 5b8:   f9400bf3        ldr     x19, [sp, #16]
	 5bc:   a8c27bfd        ldp     x29, x30, [sp], #32
	 5c0:   d65f03c0        ret
	 5c4:   d503201f        nop

The call to foo "overwrites" the x0 register for the return value,
and we end up calling the wrong secure service.

A solution is to evaluate all the parameters before assigning
anything to specific registers, leading to the expected result:

	0000000000000588 <bar>:
	 588:   a9be7bfd        stp     x29, x30, [sp, #-32]!
	 58c:   910003fd        mov     x29, sp
	 590:   f9000bf3        str     x19, [sp, #16]
	 594:   aa0003f3        mov     x19, x0
	 598:   aa1e03e0        mov     x0, x30
	 59c:   94000000        bl      0 <_mcount>
	 5a0:   94000000        bl      0 <foo>
	 5a4:   aa0003e1        mov     x1, x0
	 5a8:   d28175a0        mov     x0, #0xbad
	 5ac:   d4000003        smc     #0x0
	 5b0:   b4000073        cbz     x19, 5bc <bar+0x34>
	 5b4:   a9000660        stp     x0, x1, [x19]
	 5b8:   a9010e62        stp     x2, x3, [x19, #16]
	 5bc:   f9400bf3        ldr     x19, [sp, #16]
	 5c0:   a8c27bfd        ldp     x29, x30, [sp], #32
	 5c4:   d65f03c0        ret

Reported-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-08-30 14:18:03 +01:00
David S. Miller
f0259b6ac4 Merge tag 'mac80211-next-for-davem-2018-08-29' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Johannes Berg says:

====================
Only a few changes at this point:
 * new channels in 60 GHz
 * clarify (average) ACK signal reporting API
 * expose ieee80211_send_layer2_update() for all drivers
 * start/stop mac80211's TXQs properly when required
 * avoid regulatory restore with IE ignoring
 * spelling: contidion -> condition
 * fully implement WFA Multi-AP backhaul
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-29 22:13:47 -07:00