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2018-08-31media: v4l2-ctrls: add v4l2_ctrl_request_hdl_find/put/ctrl_find functionsHans Verkuil1-1/+48
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>
2018-08-31media: v4l2-ctrls: support g/s_ext_ctrls for requestsHans Verkuil1-1/+6
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>
2018-08-31media: v4l2-ctrls: add core request supportHans Verkuil1-0/+51
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>
2018-08-31media: v4l2-ctrls: prepare internal structs for request APIHans Verkuil1-0/+10
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>
2018-08-31media: v4l2-ctrls: v4l2_ctrl_add_handler: add from_other_devHans Verkuil1-1/+7
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>
2018-08-31media: videodev2.h: add request_fd field to v4l2_ext_controlsAlexandre Courbot1-1/+3
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>
2018-08-31media: v4l2-device.h: add v4l2_device_supports_requests() helperHans Verkuil1-0/+11
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>
2018-08-31media: media-request: add media_request_object_findHans Verkuil1-0/+28
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>
2018-08-31media: media-request: add media_request_get_by_fdHans Verkuil1-0/+24
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>
2018-08-31media: media-request: implement media requestsHans Verkuil2-0/+363
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>
2018-08-31media: uapi/linux/media.h: add request APIHans Verkuil1-0/+8
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>
2018-08-31ASoC: simple-card-util: support snd_soc_dai_link_component style for platformKuninori Morimoto1-1/+1
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>
2018-08-31ASoC: soc-core: use snd_soc_dai_link_component for platformKuninori Morimoto1-0/+2
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>
2018-08-31ASoC: simple_card_utils: support snd_soc_dai_link_component style for codecKuninori Morimoto1-9/+18
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>
2018-08-31regulator: da9063: fix DT probing with constraintsPhilipp Zabel1-7/+9
Commit 1c892e38ce59 ("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: 1c892e38ce59 ("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>
2018-08-31media: v4l2-dv-timings: Introduce v4l2_calc_timeperframe helperJose Abreu1-0/+11
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>
2018-08-31media: videodev2.h: Add new DV flag CAN_DETECT_REDUCED_FPSJose Abreu1-0/+7
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>
2018-08-31of: Add device_type access helper functionsRob Herring1-0/+12
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>
2018-08-30dt-bindings: clock: Introduce QCOM Camera clock bindingsAmit Nischal1-0/+116
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>
2018-08-30Merge branches 'doc.2018.08.30a', 'dynticks.2018.08.30b', 'srcu.2018.08.30b' and 'torture.2018.08.29a' into HEADPaul E. McKenney9-161/+169
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
2018-08-30srcu: Make early-boot call_srcu() reuse workqueue listsPaul E. McKenney2-4/+1
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>
2018-08-30srcu: Make call_srcu() available during very early bootPaul E. McKenney2-6/+10
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>
2018-08-30rcu: Remove unused rcu_dynticks_snap() from Tiny RCUPaul E. McKenney1-6/+0
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>
2018-08-30rcu: Provide functions for determining if call_rcu() has been invokedPaul E. McKenney1-0/+40
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. ]
2018-08-30rcu: Eliminate ->rcu_qs_ctr from the rcu_dynticks structurePaul E. McKenney1-3/+2
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>
2018-08-30rcu: Inline _rcu_barrier() into its sole remaining callerPaul E. McKenney1-10/+10
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>
2018-08-30rcu: Define rcu_all_qs() only in !PREEMPT buildsPaul E. McKenney1-0/+2
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>
2018-08-30rcu: Remove !PREEMPT code from rcu_note_voluntary_context_switch()Paul E. McKenney1-6/+2
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>
2018-08-30rcu: Clean up flavor-related definitions and comments in rcupdate_wait.hPaul E. McKenney1-7/+7
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30rcu: Clean up flavor-related definitions and comments in rculist.hPaul E. McKenney1-17/+15
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30rcu: Clean up flavor-related definitions and comments in rcupdate.hPaul E. McKenney1-15/+12
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30rcu: Consolidate RCU-sched update-side function definitionsPaul E. McKenney3-47/+32
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>
2018-08-30rcu: Consolidate RCU-bh update-side function definitionsPaul E. McKenney3-37/+22
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>
2018-08-30rcu: Express Tiny RCU updates in terms of RCU rather than RCU-schedPaul E. McKenney3-23/+24
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. ]
2018-08-30rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT buildsPaul E. McKenney3-11/+17
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>
2018-08-30rcu: Update comments and help text for no more RCU-bh updatersPaul E. McKenney3-23/+9
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>
2018-08-30rcu: Define RCU-bh update API in terms of RCUPaul E. McKenney3-9/+19
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>
2018-08-30rcu: Apply RCU-bh QSes to RCU-sched and RCU-preempt when safePaul E. McKenney2-0/+6
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. ]
2018-08-30rcu: Remove now-unused ->b.exp_need_qs field from the rcu_special unionPaul E. McKenney1-5/+1
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>
2018-08-30rcu: Defer reporting RCU-preempt quiescent states when disabledPaul E. McKenney1-0/+5
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(). ]
2018-08-30i2c: refactor function to release a DMA safe bufferWolfram Sang1-1/+1
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>
2018-08-30virtchnl: use u8 type for a field in the virtchnl_filter structHarshitha Ramamurthy1-1/+1
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>
2018-08-30of: add node name compare helper functionsRob Herring1-0/+13
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>
2018-08-30vfs: add the fadvise() file operationAmir Goldstein1-0/+5
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>
2018-08-30Merge tag 'hda-codec-h-move' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-nextTakashi Iwai1-0/+534
ALSA: Move hda_codec.h to include/sound For easier sharing with ASoC.
2018-08-30ALSA: hda: move hda_codec.h to include/soundPierre-Louis Bossart1-0/+534
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>
2018-08-30arm/arm64: smccc-1.1: Handle function result as parametersMarc Zyngier1-10/+20
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>
2018-08-29Merge tag 'mac80211-next-for-davem-2018-08-29' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-nextDavid S. Miller3-9/+28
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>
2018-08-29ethtool: drop get_settings and set_settings callbacksMichal Kubecek2-35/+13
Since [gs]et_settings ethtool_ops callbacks have been deprecated in February 2016, all in tree NIC drivers have been converted to provide [gs]et_link_ksettings() and out of tree drivers have had enough time to do the same. Drop get_settings() and set_settings() and implement both ETHTOOL_[GS]SET and ETHTOOL_[GS]LINKSETTINGS only using [gs]et_link_ksettings(). Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-29genetlink: constify genl_err_attr() argumentMichal Kubecek1-1/+1
genl_err_attr() sets netlink_ext_ack::bad_attr which is a pointer to const struct nlattr so make the attr argument also const. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>