Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 665 insertions, 0 deletions

diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
new file mode 100644
index 000000000..2e0f6d2e6
--- /dev/null
+++ b/include/media/v4l2-dev.h
@@ -0,0 +1,665 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *
+ *	V 4 L 2   D R I V E R   H E L P E R   A P I
+ *
+ * Moved from videodev2.h
+ *
+ *	Some commonly needed functions for drivers (v4l2-common.o module)
+ */
+#ifndef _V4L2_DEV_H
+#define _V4L2_DEV_H
+
+#include <linux/poll.h>
+#include <linux/fs.h>
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include <linux/mutex.h>
+#include <linux/videodev2.h>
+
+#include <media/media-entity.h>
+
+#define VIDEO_MAJOR	81
+
+/**
+ * enum vfl_devnode_type - type of V4L2 device node
+ *
+ * @VFL_TYPE_VIDEO:	for video input/output devices
+ * @VFL_TYPE_VBI:	for vertical blank data (i.e. closed captions, teletext)
+ * @VFL_TYPE_RADIO:	for radio tuners
+ * @VFL_TYPE_SUBDEV:	for V4L2 subdevices
+ * @VFL_TYPE_SDR:	for Software Defined Radio tuners
+ * @VFL_TYPE_TOUCH:	for touch sensors
+ * @VFL_TYPE_MAX:	number of VFL types, must always be last in the enum
+ */
+enum vfl_devnode_type {
+	VFL_TYPE_VIDEO,
+	VFL_TYPE_VBI,
+	VFL_TYPE_RADIO,
+	VFL_TYPE_SUBDEV,
+	VFL_TYPE_SDR,
+	VFL_TYPE_TOUCH,
+	VFL_TYPE_MAX /* Shall be the last one */
+};
+
+/**
+ * enum  vfl_devnode_direction - Identifies if a &struct video_device
+ * 	corresponds to a receiver, a transmitter or a mem-to-mem device.
+ *
+ * @VFL_DIR_RX:		device is a receiver.
+ * @VFL_DIR_TX:		device is a transmitter.
+ * @VFL_DIR_M2M:	device is a memory to memory device.
+ *
+ * Note: Ignored if &enum vfl_devnode_type is %VFL_TYPE_SUBDEV.
+ */
+enum vfl_devnode_direction {
+	VFL_DIR_RX,
+	VFL_DIR_TX,
+	VFL_DIR_M2M,
+};
+
+struct v4l2_ioctl_callbacks;
+struct video_device;
+struct v4l2_device;
+struct v4l2_ctrl_handler;
+struct dentry;
+
+/**
+ * enum v4l2_video_device_flags - Flags used by &struct video_device
+ *
+ * @V4L2_FL_REGISTERED:
+ *	indicates that a &struct video_device is registered.
+ *	Drivers can clear this flag if they want to block all future
+ *	device access. It is cleared by video_unregister_device.
+ * @V4L2_FL_USES_V4L2_FH:
+ *	indicates that file->private_data points to &struct v4l2_fh.
+ *	This flag is set by the core when v4l2_fh_init() is called.
+ *	All drivers must use it.
+ * @V4L2_FL_QUIRK_INVERTED_CROP:
+ *	some old M2M drivers use g/s_crop/cropcap incorrectly: crop and
+ *	compose are swapped. If this flag is set, then the selection
+ *	targets are swapped in the g/s_crop/cropcap functions in v4l2-ioctl.c.
+ *	This allows those drivers to correctly implement the selection API,
+ *	but the old crop API will still work as expected in order to preserve
+ *	backwards compatibility.
+ *	Never set this flag for new drivers.
+ * @V4L2_FL_SUBDEV_RO_DEVNODE:
+ *	indicates that the video device node is registered in read-only mode.
+ *	The flag only applies to device nodes registered for sub-devices, it is
+ *	set by the core when the sub-devices device nodes are registered with
+ *	v4l2_device_register_ro_subdev_nodes() and used by the sub-device ioctl
+ *	handler to restrict access to some ioctl calls.
+ */
+enum v4l2_video_device_flags {
+	V4L2_FL_REGISTERED		= 0,
+	V4L2_FL_USES_V4L2_FH		= 1,
+	V4L2_FL_QUIRK_INVERTED_CROP	= 2,
+	V4L2_FL_SUBDEV_RO_DEVNODE	= 3,
+};
+
+/* Priority helper functions */
+
+/**
+ * struct v4l2_prio_state - stores the priority states
+ *
+ * @prios: array with elements to store the array priorities
+ *
+ *
+ * .. note::
+ *    The size of @prios array matches the number of priority types defined
+ *    by enum &v4l2_priority.
+ */
+struct v4l2_prio_state {
+	atomic_t prios[4];
+};
+
+/**
+ * v4l2_prio_init - initializes a struct v4l2_prio_state
+ *
+ * @global: pointer to &struct v4l2_prio_state
+ */
+void v4l2_prio_init(struct v4l2_prio_state *global);
+
+/**
+ * v4l2_prio_change - changes the v4l2 file handler priority
+ *
+ * @global: pointer to the &struct v4l2_prio_state of the device node.
+ * @local: pointer to the desired priority, as defined by enum &v4l2_priority
+ * @new: Priority type requested, as defined by enum &v4l2_priority.
+ *
+ * .. note::
+ *	This function should be used only by the V4L2 core.
+ */
+int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
+		     enum v4l2_priority new);
+
+/**
+ * v4l2_prio_open - Implements the priority logic for a file handler open
+ *
+ * @global: pointer to the &struct v4l2_prio_state of the device node.
+ * @local: pointer to the desired priority, as defined by enum &v4l2_priority
+ *
+ * .. note::
+ *	This function should be used only by the V4L2 core.
+ */
+void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);
+
+/**
+ * v4l2_prio_close - Implements the priority logic for a file handler close
+ *
+ * @global: pointer to the &struct v4l2_prio_state of the device node.
+ * @local: priority to be released, as defined by enum &v4l2_priority
+ *
+ * .. note::
+ *	This function should be used only by the V4L2 core.
+ */
+void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local);
+
+/**
+ * v4l2_prio_max - Return the maximum priority, as stored at the @global array.
+ *
+ * @global: pointer to the &struct v4l2_prio_state of the device node.
+ *
+ * .. note::
+ *	This function should be used only by the V4L2 core.
+ */
+enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);
+
+/**
+ * v4l2_prio_check - Implements the priority logic for a file handler close
+ *
+ * @global: pointer to the &struct v4l2_prio_state of the device node.
+ * @local: desired priority, as defined by enum &v4l2_priority local
+ *
+ * .. note::
+ *	This function should be used only by the V4L2 core.
+ */
+int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local);
+
+/**
+ * struct v4l2_file_operations - fs operations used by a V4L2 device
+ *
+ * @owner: pointer to struct module
+ * @read: operations needed to implement the read() syscall
+ * @write: operations needed to implement the write() syscall
+ * @poll: operations needed to implement the poll() syscall
+ * @unlocked_ioctl: operations needed to implement the ioctl() syscall
+ * @compat_ioctl32: operations needed to implement the ioctl() syscall for
+ *	the special case where the Kernel uses 64 bits instructions, but
+ *	the userspace uses 32 bits.
+ * @get_unmapped_area: called by the mmap() syscall, used when %!CONFIG_MMU
+ * @mmap: operations needed to implement the mmap() syscall
+ * @open: operations needed to implement the open() syscall
+ * @release: operations needed to implement the release() syscall
+ *
+ * .. note::
+ *
+ *	Those operations are used to implemente the fs struct file_operations
+ *	at the V4L2 drivers. The V4L2 core overrides the fs ops with some
+ *	extra logic needed by the subsystem.
+ */
+struct v4l2_file_operations {
+	struct module *owner;
+	ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
+	ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
+	__poll_t (*poll) (struct file *, struct poll_table_struct *);
+	long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
+#ifdef CONFIG_COMPAT
+	long (*compat_ioctl32) (struct file *, unsigned int, unsigned long);
+#endif
+	unsigned long (*get_unmapped_area) (struct file *, unsigned long,
+				unsigned long, unsigned long, unsigned long);
+	int (*mmap) (struct file *, struct vm_area_struct *);
+	int (*open) (struct file *);
+	int (*release) (struct file *);
+};
+
+/*
+ * Newer version of video_device, handled by videodev2.c
+ *	This version moves redundant code from video device code to
+ *	the common handler
+ */
+
+/**
+ * struct video_device - Structure used to create and manage the V4L2 device
+ *	nodes.
+ *
+ * @entity: &struct media_entity
+ * @intf_devnode: pointer to &struct media_intf_devnode
+ * @pipe: &struct media_pipeline
+ * @fops: pointer to &struct v4l2_file_operations for the video device
+ * @device_caps: device capabilities as used in v4l2_capabilities
+ * @dev: &struct device for the video device
+ * @cdev: character device
+ * @v4l2_dev: pointer to &struct v4l2_device parent
+ * @dev_parent: pointer to &struct device parent
+ * @ctrl_handler: Control handler associated with this device node.
+ *	 May be NULL.
+ * @queue: &struct vb2_queue associated with this device node. May be NULL.
+ * @prio: pointer to &struct v4l2_prio_state with device's Priority state.
+ *	 If NULL, then v4l2_dev->prio will be used.
+ * @name: video device name
+ * @vfl_type: V4L device type, as defined by &enum vfl_devnode_type
+ * @vfl_dir: V4L receiver, transmitter or m2m
+ * @minor: device node 'minor'. It is set to -1 if the registration failed
+ * @num: number of the video device node
+ * @flags: video device flags. Use bitops to set/clear/test flags.
+ *	   Contains a set of &enum v4l2_video_device_flags.
+ * @index: attribute to differentiate multiple indices on one physical device
+ * @fh_lock: Lock for all v4l2_fhs
+ * @fh_list: List of &struct v4l2_fh
+ * @dev_debug: Internal device debug flags, not for use by drivers
+ * @tvnorms: Supported tv norms
+ *
+ * @release: video device release() callback
+ * @ioctl_ops: pointer to &struct v4l2_ioctl_ops with ioctl callbacks
+ *
+ * @valid_ioctls: bitmap with the valid ioctls for this device
+ * @lock: pointer to &struct mutex serialization lock
+ *
+ * .. note::
+ *	Only set @dev_parent if that can't be deduced from @v4l2_dev.
+ */
+
+struct video_device {
+#if defined(CONFIG_MEDIA_CONTROLLER)
+	struct media_entity entity;
+	struct media_intf_devnode *intf_devnode;
+	struct media_pipeline pipe;
+#endif
+	const struct v4l2_file_operations *fops;
+
+	u32 device_caps;
+
+	/* sysfs */
+	struct device dev;
+	struct cdev *cdev;
+
+	struct v4l2_device *v4l2_dev;
+	struct device *dev_parent;
+
+	struct v4l2_ctrl_handler *ctrl_handler;
+
+	struct vb2_queue *queue;
+
+	struct v4l2_prio_state *prio;
+
+	/* device info */
+	char name[64];
+	enum vfl_devnode_type vfl_type;
+	enum vfl_devnode_direction vfl_dir;
+	int minor;
+	u16 num;
+	unsigned long flags;
+	int index;
+
+	/* V4L2 file handles */
+	spinlock_t		fh_lock;
+	struct list_head	fh_list;
+
+	int dev_debug;
+
+	v4l2_std_id tvnorms;
+
+	/* callbacks */
+	void (*release)(struct video_device *vdev);
+	const struct v4l2_ioctl_ops *ioctl_ops;
+	DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE);
+
+	struct mutex *lock;
+};
+
+/**
+ * media_entity_to_video_device - Returns a &struct video_device from
+ *	the &struct media_entity embedded on it.
+ *
+ * @__entity: pointer to &struct media_entity, may be NULL
+ */
+#define media_entity_to_video_device(__entity)				\
+({									\
+	typeof(__entity) __me_vdev_ent = __entity;			\
+									\
+	__me_vdev_ent ?							\
+		container_of_const(__me_vdev_ent,  struct video_device, \
+				   entity) : NULL;			\
+})
+
+/**
+ * to_video_device - Returns a &struct video_device from the
+ *	&struct device embedded on it.
+ *
+ * @cd: pointer to &struct device
+ */
+#define to_video_device(cd) container_of_const(cd, struct video_device, dev)
+
+/**
+ * __video_register_device - register video4linux devices
+ *
+ * @vdev: struct video_device to register
+ * @type: type of device to register, as defined by &enum vfl_devnode_type
+ * @nr:   which device node number is desired:
+ *	(0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
+ * @warn_if_nr_in_use: warn if the desired device node number
+ *        was already in use and another number was chosen instead.
+ * @owner: module that owns the video device node
+ *
+ * The registration code assigns minor numbers and device node numbers
+ * based on the requested type and registers the new device node with
+ * the kernel.
+ *
+ * This function assumes that struct video_device was zeroed when it
+ * was allocated and does not contain any stale date.
+ *
+ * An error is returned if no free minor or device node number could be
+ * found, or if the registration of the device node failed.
+ *
+ * Returns 0 on success.
+ *
+ * .. note::
+ *
+ *	This function is meant to be used only inside the V4L2 core.
+ *	Drivers should use video_register_device() or
+ *	video_register_device_no_warn().
+ */
+int __must_check __video_register_device(struct video_device *vdev,
+					 enum vfl_devnode_type type,
+					 int nr, int warn_if_nr_in_use,
+					 struct module *owner);
+
+/**
+ *  video_register_device - register video4linux devices
+ *
+ * @vdev: struct video_device to register
+ * @type: type of device to register, as defined by &enum vfl_devnode_type
+ * @nr:   which device node number is desired:
+ *	(0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
+ *
+ * Internally, it calls __video_register_device(). Please see its
+ * documentation for more details.
+ *
+ * .. note::
+ *	if video_register_device fails, the release() callback of
+ *	&struct video_device structure is *not* called, so the caller
+ *	is responsible for freeing any data. Usually that means that
+ *	you video_device_release() should be called on failure.
+ */
+static inline int __must_check video_register_device(struct video_device *vdev,
+						     enum vfl_devnode_type type,
+						     int nr)
+{
+	return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);
+}
+
+/**
+ *  video_register_device_no_warn - register video4linux devices
+ *
+ * @vdev: struct video_device to register
+ * @type: type of device to register, as defined by &enum vfl_devnode_type
+ * @nr:   which device node number is desired:
+ *	(0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
+ *
+ * This function is identical to video_register_device() except that no
+ * warning is issued if the desired device node number was already in use.
+ *
+ * Internally, it calls __video_register_device(). Please see its
+ * documentation for more details.
+ *
+ * .. note::
+ *	if video_register_device fails, the release() callback of
+ *	&struct video_device structure is *not* called, so the caller
+ *	is responsible for freeing any data. Usually that means that
+ *	you video_device_release() should be called on failure.
+ */
+static inline int __must_check
+video_register_device_no_warn(struct video_device *vdev,
+			      enum vfl_devnode_type type, int nr)
+{
+	return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);
+}
+
+/**
+ * video_unregister_device - Unregister video devices.
+ *
+ * @vdev: &struct video_device to register
+ *
+ * Does nothing if vdev == NULL or if video_is_registered() returns false.
+ */
+void video_unregister_device(struct video_device *vdev);
+
+/**
+ * video_device_alloc - helper function to alloc &struct video_device
+ *
+ * Returns NULL if %-ENOMEM or a &struct video_device on success.
+ */
+struct video_device * __must_check video_device_alloc(void);
+
+/**
+ * video_device_release - helper function to release &struct video_device
+ *
+ * @vdev: pointer to &struct video_device
+ *
+ * Can also be used for video_device->release\(\).
+ */
+void video_device_release(struct video_device *vdev);
+
+/**
+ * video_device_release_empty - helper function to implement the
+ *	video_device->release\(\) callback.
+ *
+ * @vdev: pointer to &struct video_device
+ *
+ * This release function does nothing.
+ *
+ * It should be used when the video_device is a static global struct.
+ *
+ * .. note::
+ *	Having a static video_device is a dubious construction at best.
+ */
+void video_device_release_empty(struct video_device *vdev);
+
+/**
+ * v4l2_disable_ioctl- mark that a given command isn't implemented.
+ *	shouldn't use core locking
+ *
+ * @vdev: pointer to &struct video_device
+ * @cmd: ioctl command
+ *
+ * This function allows drivers to provide just one v4l2_ioctl_ops struct, but
+ * disable ioctls based on the specific card that is actually found.
+ *
+ * .. note::
+ *
+ *    This must be called before video_register_device.
+ *    See also the comments for determine_valid_ioctls().
+ */
+static inline void v4l2_disable_ioctl(struct video_device *vdev,
+				      unsigned int cmd)
+{
+	if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)
+		set_bit(_IOC_NR(cmd), vdev->valid_ioctls);
+}
+
+/**
+ * video_get_drvdata - gets private data from &struct video_device.
+ *
+ * @vdev: pointer to &struct video_device
+ *
+ * returns a pointer to the private data
+ */
+static inline void *video_get_drvdata(struct video_device *vdev)
+{
+	return dev_get_drvdata(&vdev->dev);
+}
+
+/**
+ * video_set_drvdata - sets private data from &struct video_device.
+ *
+ * @vdev: pointer to &struct video_device
+ * @data: private data pointer
+ */
+static inline void video_set_drvdata(struct video_device *vdev, void *data)
+{
+	dev_set_drvdata(&vdev->dev, data);
+}
+
+/**
+ * video_devdata - gets &struct video_device from struct file.
+ *
+ * @file: pointer to struct file
+ */
+struct video_device *video_devdata(struct file *file);
+
+/**
+ * video_drvdata - gets private data from &struct video_device using the
+ *	struct file.
+ *
+ * @file: pointer to struct file
+ *
+ * This is function combines both video_get_drvdata() and video_devdata()
+ * as this is used very often.
+ */
+static inline void *video_drvdata(struct file *file)
+{
+	return video_get_drvdata(video_devdata(file));
+}
+
+/**
+ * video_device_node_name - returns the video device name
+ *
+ * @vdev: pointer to &struct video_device
+ *
+ * Returns the device name string
+ */
+static inline const char *video_device_node_name(struct video_device *vdev)
+{
+	return dev_name(&vdev->dev);
+}
+
+/**
+ * video_is_registered - returns true if the &struct video_device is registered.
+ *
+ *
+ * @vdev: pointer to &struct video_device
+ */
+static inline int video_is_registered(struct video_device *vdev)
+{
+	return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
+}
+
+/**
+ * v4l2_debugfs_root - returns the dentry of the top-level "v4l2" debugfs dir
+ *
+ * If this directory does not yet exist, then it will be created.
+ */
+#ifdef CONFIG_DEBUG_FS
+struct dentry *v4l2_debugfs_root(void);
+#else
+static inline struct dentry *v4l2_debugfs_root(void)
+{
+	return NULL;
+}
+#endif
+
+#if defined(CONFIG_MEDIA_CONTROLLER)
+
+/**
+ * video_device_pipeline_start - Mark a pipeline as streaming
+ * @vdev: Starting video device
+ * @pipe: Media pipeline to be assigned to all entities in the pipeline.
+ *
+ * Mark all entities connected to a given video device through enabled links,
+ * either directly or indirectly, as streaming. The given pipeline object is
+ * assigned to every pad in the pipeline and stored in the media_pad pipe
+ * field.
+ *
+ * Calls to this function can be nested, in which case the same number of
+ * video_device_pipeline_stop() calls will be required to stop streaming. The
+ * pipeline pointer must be identical for all nested calls to
+ * video_device_pipeline_start().
+ *
+ * The video device must contain a single pad.
+ *
+ * This is a convenience wrapper around media_pipeline_start().
+ */
+__must_check int video_device_pipeline_start(struct video_device *vdev,
+					     struct media_pipeline *pipe);
+
+/**
+ * __video_device_pipeline_start - Mark a pipeline as streaming
+ * @vdev: Starting video device
+ * @pipe: Media pipeline to be assigned to all entities in the pipeline.
+ *
+ * ..note:: This is the non-locking version of video_device_pipeline_start()
+ *
+ * The video device must contain a single pad.
+ *
+ * This is a convenience wrapper around __media_pipeline_start().
+ */
+__must_check int __video_device_pipeline_start(struct video_device *vdev,
+					       struct media_pipeline *pipe);
+
+/**
+ * video_device_pipeline_stop - Mark a pipeline as not streaming
+ * @vdev: Starting video device
+ *
+ * Mark all entities connected to a given video device through enabled links,
+ * either directly or indirectly, as not streaming. The media_pad pipe field
+ * is reset to %NULL.
+ *
+ * If multiple calls to media_pipeline_start() have been made, the same
+ * number of calls to this function are required to mark the pipeline as not
+ * streaming.
+ *
+ * The video device must contain a single pad.
+ *
+ * This is a convenience wrapper around media_pipeline_stop().
+ */
+void video_device_pipeline_stop(struct video_device *vdev);
+
+/**
+ * __video_device_pipeline_stop - Mark a pipeline as not streaming
+ * @vdev: Starting video device
+ *
+ * .. note:: This is the non-locking version of media_pipeline_stop()
+ *
+ * The video device must contain a single pad.
+ *
+ * This is a convenience wrapper around __media_pipeline_stop().
+ */
+void __video_device_pipeline_stop(struct video_device *vdev);
+
+/**
+ * video_device_pipeline_alloc_start - Mark a pipeline as streaming
+ * @vdev: Starting video device
+ *
+ * video_device_pipeline_alloc_start() is similar to video_device_pipeline_start()
+ * but instead of working on a given pipeline the function will use an
+ * existing pipeline if the video device is already part of a pipeline, or
+ * allocate a new pipeline.
+ *
+ * Calls to video_device_pipeline_alloc_start() must be matched with
+ * video_device_pipeline_stop().
+ */
+__must_check int video_device_pipeline_alloc_start(struct video_device *vdev);
+
+/**
+ * video_device_pipeline - Get the media pipeline a video device is part of
+ * @vdev: The video device
+ *
+ * This function returns the media pipeline that a video device has been
+ * associated with when constructing the pipeline with
+ * video_device_pipeline_start(). The pointer remains valid until
+ * video_device_pipeline_stop() is called.
+ *
+ * Return: The media_pipeline the video device is part of, or NULL if the video
+ * device is not part of any pipeline.
+ *
+ * The video device must contain a single pad.
+ *
+ * This is a convenience wrapper around media_entity_pipeline().
+ */
+struct media_pipeline *video_device_pipeline(struct video_device *vdev);
+
+#endif /* CONFIG_MEDIA_CONTROLLER */
+
+#endif /* _V4L2_DEV_H */