diff options
Diffstat (limited to 'include/media/videobuf2-core.h')
| -rw-r--r-- | include/media/videobuf2-core.h | 861 |
1 files changed, 588 insertions, 273 deletions
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index cb97c224be73..9b02aeba4108 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -16,6 +16,9 @@ #include <linux/mutex.h> #include <linux/poll.h> #include <linux/dma-buf.h> +#include <linux/bitops.h> +#include <media/media-request.h> +#include <media/frame_vector.h> #define VB2_MAX_FRAME (32) #define VB2_MAX_PLANES (8) @@ -43,16 +46,16 @@ enum vb2_memory { struct vb2_fileio_data; struct vb2_threadio_data; +struct vb2_buffer; /** - * struct vb2_mem_ops - memory handling/memory allocator operations + * struct vb2_mem_ops - memory handling/memory allocator operations. * @alloc: allocate video memory and, optionally, allocator private data, * return ERR_PTR() on failure or a pointer to allocator private, * per-buffer data on success; the returned private structure * will then be passed as @buf_priv argument to other ops in this - * structure. Additional gfp_flags to use when allocating the - * are also passed to this operation. These flags are from the - * gfp_flags field of vb2_queue. + * structure. The size argument to this function shall be + * *page aligned*. * @put: inform the allocator that the buffer will no longer be used; * usually will result in the allocator freeing the buffer (if * no other users of this buffer are present); the @buf_priv @@ -62,14 +65,18 @@ struct vb2_threadio_data; * DMABUF memory types. * @get_userptr: acquire userspace memory for a hardware operation; used for * USERPTR memory types; vaddr is the address passed to the - * videobuf layer when queuing a video buffer of USERPTR type; + * videobuf2 layer when queuing a video buffer of USERPTR type; * should return an allocator private per-buffer structure * associated with the buffer on success, ERR_PTR() on failure; * the returned private structure will then be passed as @buf_priv * argument to other ops in this structure. * @put_userptr: inform the allocator that a USERPTR buffer will no longer * be used. - * @attach_dmabuf: attach a shared struct dma_buf for a hardware operation; + * @prepare: called every time the buffer is passed from userspace to the + * driver, useful for cache synchronisation, optional. + * @finish: called every time the buffer is passed back from the driver + * to the userspace, also optional. + * @attach_dmabuf: attach a shared &struct dma_buf for a hardware operation; * used for DMABUF memory types; dev is the alloc device * dbuf is the shared dma_buf; returns ERR_PTR() on failure; * allocator private per-buffer structure on success; @@ -83,10 +90,6 @@ struct vb2_threadio_data; * dmabuf. * @unmap_dmabuf: releases access control to the dmabuf - allocator is notified * that this driver is done using the dmabuf for now. - * @prepare: called every time the buffer is passed from userspace to the - * driver, useful for cache synchronisation, optional. - * @finish: called every time the buffer is passed back from the driver - * to the userspace, also optional. * @vaddr: return a kernel virtual address to a given memory buffer * associated with the passed private structure or NULL if no * such mapping exists. @@ -94,7 +97,7 @@ struct vb2_threadio_data; * associated with the passed private structure or NULL if not * available. * @num_users: return the current number of users of a memory buffer; - * return 1 if the videobuf layer (or actually the driver using + * return 1 if the videobuf2 layer (or actually the driver using * it) is the only user. * @mmap: setup a userspace mapping for a given memory buffer under * the provided virtual memory region. @@ -113,31 +116,33 @@ struct vb2_threadio_data; * map_dmabuf, unmap_dmabuf. */ struct vb2_mem_ops { - void *(*alloc)(struct device *dev, unsigned long attrs, - unsigned long size, - enum dma_data_direction dma_dir, - gfp_t gfp_flags); + void *(*alloc)(struct vb2_buffer *vb, + struct device *dev, + unsigned long size); void (*put)(void *buf_priv); - struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags); - - void *(*get_userptr)(struct device *dev, unsigned long vaddr, - unsigned long size, - enum dma_data_direction dma_dir); + struct dma_buf *(*get_dmabuf)(struct vb2_buffer *vb, + void *buf_priv, + unsigned long flags); + + void *(*get_userptr)(struct vb2_buffer *vb, + struct device *dev, + unsigned long vaddr, + unsigned long size); void (*put_userptr)(void *buf_priv); void (*prepare)(void *buf_priv); void (*finish)(void *buf_priv); - void *(*attach_dmabuf)(struct device *dev, + void *(*attach_dmabuf)(struct vb2_buffer *vb, + struct device *dev, struct dma_buf *dbuf, - unsigned long size, - enum dma_data_direction dma_dir); + unsigned long size); void (*detach_dmabuf)(void *buf_priv); int (*map_dmabuf)(void *buf_priv); void (*unmap_dmabuf)(void *buf_priv); - void *(*vaddr)(void *buf_priv); - void *(*cookie)(void *buf_priv); + void *(*vaddr)(struct vb2_buffer *vb, void *buf_priv); + void *(*cookie)(struct vb2_buffer *vb, void *buf_priv); unsigned int (*num_users)(void *buf_priv); @@ -145,33 +150,38 @@ struct vb2_mem_ops { }; /** - * struct vb2_plane - plane information - * @mem_priv: private data with this plane - * @dbuf: dma_buf - shared buffer object + * struct vb2_plane - plane information. + * @mem_priv: private data with this plane. + * @dbuf: dma_buf - shared buffer object. * @dbuf_mapped: flag to show whether dbuf is mapped or not - * @bytesused: number of bytes occupied by data in the plane (payload) - * @length: size of this plane (NOT the payload) in bytes + * @dbuf_duplicated: boolean to show whether dbuf is duplicated with a + * previous plane of the buffer. + * @bytesused: number of bytes occupied by data in the plane (payload). + * @length: size of this plane (NOT the payload) in bytes. The maximum + * valid size is MAX_UINT - PAGE_SIZE. * @min_length: minimum required size of this plane (NOT the payload) in bytes. - * @length is always greater or equal to @min_length. - * @offset: when memory in the associated struct vb2_buffer is - * VB2_MEMORY_MMAP, equals the offset from the start of + * @length is always greater or equal to @min_length, and like + * @length, it is limited to MAX_UINT - PAGE_SIZE. + * @m: Union with memtype-specific data. + * @m.offset: when memory in the associated struct vb2_buffer is + * %VB2_MEMORY_MMAP, equals the offset from the start of * the device memory for this plane (or is a "cookie" that - * should be passed to mmap() called on the video node) - * @userptr: when memory is VB2_MEMORY_USERPTR, a userspace pointer - * pointing to this plane - * @fd: when memory is VB2_MEMORY_DMABUF, a userspace file - * descriptor associated with this plane - * @m: Union with memtype-specific data (@offset, @userptr or - * @fd). + * should be passed to mmap() called on the video node). + * @m.userptr: when memory is %VB2_MEMORY_USERPTR, a userspace pointer + * pointing to this plane. + * @m.fd: when memory is %VB2_MEMORY_DMABUF, a userspace file + * descriptor associated with this plane. * @data_offset: offset in the plane to the start of data; usually 0, - * unless there is a header in front of the data + * unless there is a header in front of the data. + * * Should contain enough information to be able to cover all the fields - * of struct v4l2_plane at videodev2.h + * of &struct v4l2_plane at videodev2.h. */ struct vb2_plane { void *mem_priv; struct dma_buf *dbuf; unsigned int dbuf_mapped; + bool dbuf_duplicated; unsigned int bytesused; unsigned int length; unsigned int min_length; @@ -184,42 +194,40 @@ struct vb2_plane { }; /** - * enum vb2_io_modes - queue access methods - * @VB2_MMAP: driver supports MMAP with streaming API - * @VB2_USERPTR: driver supports USERPTR with streaming API - * @VB2_READ: driver supports read() style access - * @VB2_WRITE: driver supports write() style access - * @VB2_DMABUF: driver supports DMABUF with streaming API + * enum vb2_io_modes - queue access methods. + * @VB2_MMAP: driver supports MMAP with streaming API. + * @VB2_USERPTR: driver supports USERPTR with streaming API. + * @VB2_READ: driver supports read() style access. + * @VB2_WRITE: driver supports write() style access. + * @VB2_DMABUF: driver supports DMABUF with streaming API. */ enum vb2_io_modes { - VB2_MMAP = (1 << 0), - VB2_USERPTR = (1 << 1), - VB2_READ = (1 << 2), - VB2_WRITE = (1 << 3), - VB2_DMABUF = (1 << 4), + VB2_MMAP = BIT(0), + VB2_USERPTR = BIT(1), + VB2_READ = BIT(2), + VB2_WRITE = BIT(3), + VB2_DMABUF = BIT(4), }; /** - * enum vb2_buffer_state - current video buffer state - * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control - * @VB2_BUF_STATE_PREPARING: buffer is being prepared in videobuf - * @VB2_BUF_STATE_PREPARED: buffer prepared in videobuf and by the driver - * @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in driver - * @VB2_BUF_STATE_REQUEUEING: re-queue a buffer to the driver + * enum vb2_buffer_state - current video buffer state. + * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control. + * @VB2_BUF_STATE_IN_REQUEST: buffer is queued in media request. + * @VB2_BUF_STATE_PREPARING: buffer is being prepared in videobuf2. + * @VB2_BUF_STATE_QUEUED: buffer queued in videobuf2, but not in driver. * @VB2_BUF_STATE_ACTIVE: buffer queued in driver and possibly used - * in a hardware operation - * @VB2_BUF_STATE_DONE: buffer returned from driver to videobuf, but - * not yet dequeued to userspace + * in a hardware operation. + * @VB2_BUF_STATE_DONE: buffer returned from driver to videobuf2, but + * not yet dequeued to userspace. * @VB2_BUF_STATE_ERROR: same as above, but the operation on the buffer * has ended with an error, which will be reported - * to the userspace when it is dequeued + * to the userspace when it is dequeued. */ enum vb2_buffer_state { VB2_BUF_STATE_DEQUEUED, + VB2_BUF_STATE_IN_REQUEST, VB2_BUF_STATE_PREPARING, - VB2_BUF_STATE_PREPARED, VB2_BUF_STATE_QUEUED, - VB2_BUF_STATE_REQUEUEING, VB2_BUF_STATE_ACTIVE, VB2_BUF_STATE_DONE, VB2_BUF_STATE_ERROR, @@ -228,15 +236,18 @@ enum vb2_buffer_state { struct vb2_queue; /** - * struct vb2_buffer - represents a video buffer - * @vb2_queue: the queue to which this driver belongs - * @index: id number of the buffer - * @type: buffer type - * @memory: the method, in which the actual data is passed + * struct vb2_buffer - represents a video buffer. + * @vb2_queue: pointer to &struct vb2_queue with the queue to + * which this driver belongs. + * @index: id number of the buffer. + * @type: buffer type. + * @memory: the method, in which the actual data is passed. * @num_planes: number of planes in the buffer - * on an internal driver queue - * @planes: private per-plane information; do not change - * @timestamp: frame timestamp in ns + * on an internal driver queue. + * @timestamp: frame timestamp in ns. + * @request: the request this buffer is associated with. + * @req_obj: used to bind this buffer to a request. This + * request object has a refcount. */ struct vb2_buffer { struct vb2_queue *vb2_queue; @@ -244,19 +255,39 @@ struct vb2_buffer { unsigned int type; unsigned int memory; unsigned int num_planes; - struct vb2_plane planes[VB2_MAX_PLANES]; u64 timestamp; + struct media_request *request; + struct media_request_object req_obj; /* private: internal use only * * state: current buffer state; do not change + * synced: this buffer has been synced for DMA, i.e. the + * 'prepare' memop was called. It is cleared again + * after the 'finish' memop is called. + * prepared: this buffer has been prepared, i.e. the + * buf_prepare op was called. It is cleared again + * after the 'buf_finish' op is called. + * copied_timestamp: the timestamp of this capture buffer was copied + * from an output buffer. + * skip_cache_sync_on_prepare: when set buffer's ->prepare() function + * skips cache sync/invalidation. + * skip_cache_sync_on_finish: when set buffer's ->finish() function + * skips cache sync/invalidation. + * planes: per-plane information; do not change * queued_entry: entry on the queued buffers list, which holds * all buffers queued from userspace * done_entry: entry on the list that stores all buffers ready * to be dequeued to userspace */ enum vb2_buffer_state state; + unsigned int synced:1; + unsigned int prepared:1; + unsigned int copied_timestamp:1; + unsigned int skip_cache_sync_on_prepare:1; + unsigned int skip_cache_sync_on_finish:1; + struct vb2_plane planes[VB2_MAX_PLANES]; struct list_head queued_entry; struct list_head done_entry; #ifdef CONFIG_VIDEO_ADV_DEBUG @@ -280,11 +311,13 @@ struct vb2_buffer { u32 cnt_mem_num_users; u32 cnt_mem_mmap; + u32 cnt_buf_out_validate; u32 cnt_buf_init; u32 cnt_buf_prepare; u32 cnt_buf_finish; u32 cnt_buf_cleanup; u32 cnt_buf_queue; + u32 cnt_buf_request_complete; /* This counts the number of calls to vb2_buffer_done() */ u32 cnt_buf_done; @@ -292,7 +325,10 @@ struct vb2_buffer { }; /** - * struct vb2_ops - driver-specific callbacks + * struct vb2_ops - driver-specific callbacks. + * + * These operations are not called from interrupt context except where + * mentioned specifically. * * @queue_setup: called from VIDIOC_REQBUFS() and VIDIOC_CREATE_BUFS() * handlers before memory allocation. It can be called @@ -313,8 +349,8 @@ struct vb2_buffer { * describes the requested number of planes and sizes\[\] * contains the requested plane sizes. In this case * \*num_buffers are being allocated additionally to - * q->num_buffers. If either \*num_planes or the requested - * sizes are invalid callback must return %-EINVAL. + * the buffers already allocated. If either \*num_planes + * or the requested sizes are invalid callback must return %-EINVAL. * @wait_prepare: release any locks taken while calling vb2 functions; * it is called before an ioctl needs to wait for a new * buffer to arrive; required to avoid a deadlock in @@ -322,6 +358,10 @@ struct vb2_buffer { * @wait_finish: reacquire all locks released in the previous callback; * required to continue operation after sleeping while * waiting for a new buffer to arrive. + * @buf_out_validate: called when the output buffer is prepared or queued + * to a request; drivers can use this to validate + * userspace-provided information; this is required only + * for OUTPUT queues. * @buf_init: called once after allocating a buffer (in MMAP case) * or after acquiring a new USERPTR buffer; drivers may * perform additional buffer-related initialization; @@ -349,6 +389,12 @@ struct vb2_buffer { * the buffer contents will be ignored anyway. * @buf_cleanup: called once before the buffer is freed; drivers may * perform any additional cleanup; optional. + * @prepare_streaming: called once to prepare for 'streaming' state; this is + * where validation can be done to verify everything is + * okay and streaming resources can be claimed. It is + * called when the VIDIOC_STREAMON ioctl is called. The + * actual streaming starts when @start_streaming is called. + * Optional. * @start_streaming: called once to enter 'streaming' state; the driver may * receive buffers with @buf_queue callback * before @start_streaming is called; the driver gets the @@ -358,23 +404,32 @@ struct vb2_buffer { * the @buf_queue callback are to be returned by the driver * by calling vb2_buffer_done() with %VB2_BUF_STATE_QUEUED. * If you need a minimum number of buffers before you can - * start streaming, then set @min_buffers_needed in the - * vb2_queue structure. If that is non-zero then - * @start_streaming won't be called until at least that - * many buffers have been queued up by userspace. + * start streaming, then set + * &vb2_queue->min_queued_buffers. If that is non-zero + * then @start_streaming won't be called until at least + * that many buffers have been queued up by userspace. * @stop_streaming: called when 'streaming' state must be disabled; driver * should stop any DMA transactions or wait until they * finish and give back all buffers it got from &buf_queue * callback by calling vb2_buffer_done() with either * %VB2_BUF_STATE_DONE or %VB2_BUF_STATE_ERROR; may use * vb2_wait_for_all_buffers() function + * @unprepare_streaming:called as counterpart to @prepare_streaming; any claimed + * streaming resources can be released here. It is + * called when the VIDIOC_STREAMOFF ioctls is called or + * when the streaming filehandle is closed. Optional. * @buf_queue: passes buffer vb to the driver; driver may start * hardware operation on this buffer; driver should give * the buffer back by calling vb2_buffer_done() function; - * it is allways called after calling VIDIOC_STREAMON() + * it is always called after calling VIDIOC_STREAMON() * ioctl; might be called before @start_streaming callback * if user pre-queued buffers before calling * VIDIOC_STREAMON(). + * @buf_request_complete: a buffer that was never queued to the driver but is + * associated with a queued request was canceled. + * The driver will have to mark associated objects in the + * request as completed; required if requests are + * supported. */ struct vb2_ops { int (*queue_setup)(struct vb2_queue *q, @@ -384,56 +439,88 @@ struct vb2_ops { void (*wait_prepare)(struct vb2_queue *q); void (*wait_finish)(struct vb2_queue *q); + int (*buf_out_validate)(struct vb2_buffer *vb); int (*buf_init)(struct vb2_buffer *vb); int (*buf_prepare)(struct vb2_buffer *vb); void (*buf_finish)(struct vb2_buffer *vb); void (*buf_cleanup)(struct vb2_buffer *vb); + int (*prepare_streaming)(struct vb2_queue *q); int (*start_streaming)(struct vb2_queue *q, unsigned int count); void (*stop_streaming)(struct vb2_queue *q); + void (*unprepare_streaming)(struct vb2_queue *q); void (*buf_queue)(struct vb2_buffer *vb); + + void (*buf_request_complete)(struct vb2_buffer *vb); }; /** - * struct vb2_buf_ops - driver-specific callbacks + * struct vb2_buf_ops - driver-specific callbacks. * * @verify_planes_array: Verify that a given user space structure contains * enough planes for the buffer. This is called * for each dequeued buffer. - * @fill_user_buffer: given a vb2_buffer fill in the userspace structure. - * For V4L2 this is a struct v4l2_buffer. - * @fill_vb2_buffer: given a userspace structure, fill in the vb2_buffer. + * @init_buffer: given a &vb2_buffer initialize the extra data after + * struct vb2_buffer. + * For V4L2 this is a &struct vb2_v4l2_buffer. + * @fill_user_buffer: given a &vb2_buffer fill in the userspace structure. + * For V4L2 this is a &struct v4l2_buffer. + * @fill_vb2_buffer: given a userspace structure, fill in the &vb2_buffer. * If the userspace structure is invalid, then this op * will return an error. * @copy_timestamp: copy the timestamp from a userspace structure to - * the vb2_buffer struct. + * the &struct vb2_buffer. */ struct vb2_buf_ops { int (*verify_planes_array)(struct vb2_buffer *vb, const void *pb); + void (*init_buffer)(struct vb2_buffer *vb); void (*fill_user_buffer)(struct vb2_buffer *vb, void *pb); - int (*fill_vb2_buffer)(struct vb2_buffer *vb, const void *pb, - struct vb2_plane *planes); + int (*fill_vb2_buffer)(struct vb2_buffer *vb, struct vb2_plane *planes); void (*copy_timestamp)(struct vb2_buffer *vb, const void *pb); }; /** - * struct vb2_queue - a videobuf queue + * struct vb2_queue - a videobuf2 queue. * * @type: private buffer type whose content is defined by the vb2-core * caller. For example, for V4L2, it should match - * the types defined on enum &v4l2_buf_type - * @io_modes: supported io methods (see vb2_io_modes enum) + * the types defined on &enum v4l2_buf_type. + * @io_modes: supported io methods (see &enum vb2_io_modes). * @dev: device to use for the default allocation context if the driver * doesn't fill in the @alloc_devs array. * @dma_attrs: DMA attributes to use for the DMA. + * @bidirectional: when this flag is set the DMA direction for the buffers of + * this queue will be overridden with %DMA_BIDIRECTIONAL direction. + * This is useful in cases where the hardware (firmware) writes to + * a buffer which is mapped as read (%DMA_TO_DEVICE), or reads from + * buffer which is mapped for write (%DMA_FROM_DEVICE) in order + * to satisfy some internal hardware restrictions or adds a padding + * needed by the processing algorithm. In case the DMA mapping is + * not bidirectional but the hardware (firmware) trying to access + * the buffer (in the opposite direction) this could lead to an + * IOMMU protection faults. * @fileio_read_once: report EOF after reading the first buffer * @fileio_write_immediately: queue buffer after each write() call * @allow_zero_bytesused: allow bytesused == 0 to be passed to the driver - * @quirk_poll_must_check_waiting_for_buffers: Return POLLERR at poll when QBUF + * @quirk_poll_must_check_waiting_for_buffers: Return %EPOLLERR at poll when QBUF * has not been called. This is a vb1 idiom that has been adopted * also by vb2. - * @lock: pointer to a mutex that protects the vb2_queue struct. The + * @supports_requests: this queue supports the Request API. + * @requires_requests: this queue requires the Request API. If this is set to 1, + * then supports_requests must be set to 1 as well. + * @uses_qbuf: qbuf was used directly for this queue. Set to 1 the first + * time this is called. Set to 0 when the queue is canceled. + * If this is 1, then you cannot queue buffers from a request. + * @uses_requests: requests are used for this queue. Set to 1 the first time + * a request is queued. Set to 0 when the queue is canceled. + * If this is 1, then you cannot queue buffers directly. + * @allow_cache_hints: when set user-space can pass cache management hints in + * order to skip cache flush/invalidation on ->prepare() or/and + * ->finish(). + * @non_coherent_mem: when set queue will attempt to allocate buffers using + * non-coherent memory. + * @lock: pointer to a mutex that protects the &struct vb2_queue. The * driver can set this to a mutex to let the v4l2 core serialize * the queuing ioctls. If the driver wants to handle locking * itself, then this should be set to NULL. This lock is not used @@ -444,61 +531,99 @@ struct vb2_buf_ops { * drivers to easily associate an owner filehandle with the queue. * @ops: driver-specific callbacks * @mem_ops: memory allocator specific callbacks - * @buf_ops: callbacks to deliver buffer information - * between user-space and kernel-space - * @drv_priv: driver private data + * @buf_ops: callbacks to deliver buffer information. + * between user-space and kernel-space. + * @drv_priv: driver private data. + * @subsystem_flags: Flags specific to the subsystem (V4L2/DVB/etc.). Not used + * by the vb2 core. * @buf_struct_size: size of the driver-specific buffer structure; * "0" indicates the driver doesn't want to use a custom buffer - * structure type. for example, sizeof(struct vb2_v4l2_buffer) - * will be used for v4l2. - * @timestamp_flags: Timestamp flags; V4L2_BUF_FLAG_TIMESTAMP_* and - * V4L2_BUF_FLAG_TSTAMP_SRC_* + * structure type. In that case a subsystem-specific struct + * will be used (in the case of V4L2 that is + * ``sizeof(struct vb2_v4l2_buffer)``). The first field of the + * driver-specific buffer structure must be the subsystem-specific + * struct (vb2_v4l2_buffer in the case of V4L2). + * @timestamp_flags: Timestamp flags; ``V4L2_BUF_FLAG_TIMESTAMP_*`` and + * ``V4L2_BUF_FLAG_TSTAMP_SRC_*`` * @gfp_flags: additional gfp flags used when allocating the buffers. - * Typically this is 0, but it may be e.g. GFP_DMA or __GFP_DMA32 + * Typically this is 0, but it may be e.g. %GFP_DMA or %__GFP_DMA32 * to force the buffer allocation to a specific memory zone. - * @min_buffers_needed: the minimum number of buffers needed before + * @min_queued_buffers: the minimum number of queued buffers needed before * @start_streaming can be called. Used when a DMA engine * cannot be started unless at least this number of buffers * have been queued into the driver. + * VIDIOC_REQBUFS will ensure at least @min_queued_buffers + 1 + * buffers will be allocated. Note that VIDIOC_CREATE_BUFS will not + * modify the requested buffer count. + * @min_reqbufs_allocation: the minimum number of buffers to be allocated when + * calling VIDIOC_REQBUFS. Note that VIDIOC_CREATE_BUFS will *not* + * modify the requested buffer count and does not use this field. + * Drivers can set this if there has to be a certain number of + * buffers available for the hardware to work effectively. + * This allows calling VIDIOC_REQBUFS with a buffer count of 1 and + * it will be automatically adjusted to a workable buffer count. + * If set, then @min_reqbufs_allocation must be larger than + * @min_queued_buffers + 1. + * If this field is > 3, then it is highly recommended that the + * driver implements the V4L2_CID_MIN_BUFFERS_FOR_CAPTURE/OUTPUT + * control. + * @alloc_devs: &struct device memory type/allocator-specific per-plane device */ /* * Private elements (won't appear at the uAPI book): * @mmap_lock: private mutex used when buffers are allocated/freed/mmapped * @memory: current memory type used - * @bufs: videobuf buffer structures - * @num_buffers: number of allocated/used buffers + * @dma_dir: DMA mapping direction. + * @bufs: videobuf2 buffer structures. If it is non-NULL then + * bufs_bitmap is also non-NULL. + * @bufs_bitmap: bitmap tracking whether each bufs[] entry is used + * @max_num_buffers: upper limit of number of allocated/used buffers. + * If set to 0 v4l2 core will change it VB2_MAX_FRAME + * for backward compatibility. * @queued_list: list of buffers currently queued from userspace * @queued_count: number of buffers queued and ready for streaming. * @owned_by_drv_count: number of buffers owned by the driver * @done_list: list of buffers ready to be dequeued to userspace * @done_lock: lock to protect done_list list * @done_wq: waitqueue for processes waiting for buffers ready to be dequeued - * @alloc_devs: memory type/allocator-specific per-plane device * @streaming: current streaming state * @start_streaming_called: @start_streaming was called successfully and we * started streaming. * @error: a fatal error occurred on the queue * @waiting_for_buffers: used in poll() to check if vb2 is still waiting for * buffers. Only set for capture queues if qbuf has not yet been - * called since poll() needs to return POLLERR in that situation. + * called since poll() needs to return %EPOLLERR in that situation. + * @waiting_in_dqbuf: set by the core for the duration of a blocking DQBUF, when + * it has to wait for a buffer to become available with vb2_queue->lock + * released. Used to prevent destroying the queue by other threads. * @is_multiplanar: set if buffer type is multiplanar * @is_output: set if buffer type is output + * @is_busy: set if at least one buffer has been allocated at some time. * @copy_timestamp: set if vb2-core should set timestamps * @last_buffer_dequeued: used in poll() and DQBUF to immediately return if the * last decoded buffer was already dequeued. Set for capture queues - * when a buffer with the V4L2_BUF_FLAG_LAST is dequeued. + * when a buffer with the %V4L2_BUF_FLAG_LAST is dequeued. * @fileio: file io emulator internal data, used only if emulator is active * @threadio: thread io internal data, used only if thread is active + * @name: queue name, used for logging purpose. Initialized automatically + * if left empty by drivers. */ struct vb2_queue { unsigned int type; unsigned int io_modes; struct device *dev; unsigned long dma_attrs; - unsigned fileio_read_once:1; - unsigned fileio_write_immediately:1; - unsigned allow_zero_bytesused:1; - unsigned quirk_poll_must_check_waiting_for_buffers:1; + unsigned int bidirectional:1; + unsigned int fileio_read_once:1; + unsigned int fileio_write_immediately:1; + unsigned int allow_zero_bytesused:1; + unsigned int quirk_poll_must_check_waiting_for_buffers:1; + unsigned int supports_requests:1; + unsigned int requires_requests:1; + unsigned int uses_qbuf:1; + unsigned int uses_requests:1; + unsigned int allow_cache_hints:1; + unsigned int non_coherent_mem:1; struct mutex *lock; void *owner; @@ -508,16 +633,22 @@ struct vb2_queue { const struct vb2_buf_ops *buf_ops; void *drv_priv; + u32 subsystem_flags; unsigned int buf_struct_size; u32 timestamp_flags; gfp_t gfp_flags; - u32 min_buffers_needed; + u32 min_queued_buffers; + u32 min_reqbufs_allocation; + + struct device *alloc_devs[VB2_MAX_PLANES]; /* private: internal use only */ struct mutex mmap_lock; unsigned int memory; - struct vb2_buffer *bufs[VB2_MAX_FRAME]; - unsigned int num_buffers; + enum dma_data_direction dma_dir; + struct vb2_buffer **bufs; + unsigned long *bufs_bitmap; + unsigned int max_num_buffers; struct list_head queued_list; unsigned int queued_count; @@ -527,20 +658,22 @@ struct vb2_queue { spinlock_t done_lock; wait_queue_head_t done_wq; - struct device *alloc_devs[VB2_MAX_PLANES]; - unsigned int streaming:1; unsigned int start_streaming_called:1; unsigned int error:1; unsigned int waiting_for_buffers:1; + unsigned int waiting_in_dqbuf:1; unsigned int is_multiplanar:1; unsigned int is_output:1; + unsigned int is_busy:1; unsigned int copy_timestamp:1; unsigned int last_buffer_dequeued:1; struct vb2_fileio_data *fileio; struct vb2_threadio_data *threadio; + char name[32]; + #ifdef CONFIG_VIDEO_ADV_DEBUG /* * Counters for how often these queue-related ops are @@ -549,15 +682,29 @@ struct vb2_queue { u32 cnt_queue_setup; u32 cnt_wait_prepare; u32 cnt_wait_finish; + u32 cnt_prepare_streaming; u32 cnt_start_streaming; u32 cnt_stop_streaming; + u32 cnt_unprepare_streaming; #endif }; /** - * vb2_plane_vaddr() - Return a kernel virtual address of a given plane - * @vb: vb2_buffer to which the plane in question belongs to - * @plane_no: plane number for which the address is to be returned + * vb2_queue_allows_cache_hints() - Return true if the queue allows cache + * and memory consistency hints. + * + * @q: pointer to &struct vb2_queue with videobuf2 queue + */ +static inline bool vb2_queue_allows_cache_hints(struct vb2_queue *q) +{ + return q->allow_cache_hints && q->memory == VB2_MEMORY_MMAP; +} + +/** + * vb2_plane_vaddr() - Return a kernel virtual address of a given plane. + * @vb: pointer to &struct vb2_buffer to which the plane in + * question belongs to. + * @plane_no: plane number for which the address is to be returned. * * This function returns a kernel virtual address of a given plane if * such a mapping exist, NULL otherwise. @@ -565,9 +712,10 @@ struct vb2_queue { void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no); /** - * vb2_plane_cookie() - Return allocator specific cookie for the given plane - * @vb: vb2_buffer to which the plane in question belongs to - * @plane_no: plane number for which the cookie is to be returned + * vb2_plane_cookie() - Return allocator specific cookie for the given plane. + * @vb: pointer to &struct vb2_buffer to which the plane in + * question belongs to. + * @plane_no: plane number for which the cookie is to be returned. * * This function returns an allocator specific cookie for a given plane if * available, NULL otherwise. The allocator should provide some simple static @@ -578,14 +726,13 @@ void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no); void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no); /** - * vb2_buffer_done() - inform videobuf that an operation on a buffer is finished - * @vb: vb2_buffer returned from the driver - * @state: either %VB2_BUF_STATE_DONE if the operation finished + * vb2_buffer_done() - inform videobuf2 that an operation on a buffer + * is finished. + * @vb: pointer to &struct vb2_buffer to be used. + * @state: state of the buffer, as defined by &enum vb2_buffer_state. + * Either %VB2_BUF_STATE_DONE if the operation finished * successfully, %VB2_BUF_STATE_ERROR if the operation finished - * with an error or %VB2_BUF_STATE_QUEUED if the driver wants to - * requeue buffers. If start_streaming fails then it should return - * buffers with state %VB2_BUF_STATE_QUEUED to put them back into - * the queue. + * with an error or %VB2_BUF_STATE_QUEUED. * * This function should be called by the driver after a hardware operation on * a buffer is finished and the buffer may be returned to userspace. The driver @@ -594,15 +741,15 @@ void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no); * to the driver by &vb2_ops->buf_queue can be passed to this function. * * While streaming a buffer can only be returned in state DONE or ERROR. - * The start_streaming op can also return them in case the DMA engine cannot - * be started for some reason. In that case the buffers should be returned with - * state QUEUED. + * The &vb2_ops->start_streaming op can also return them in case the DMA engine + * cannot be started for some reason. In that case the buffers should be + * returned with state QUEUED to put them back into the queue. */ void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state); /** - * vb2_discard_done() - discard all buffers marked as DONE - * @q: videobuf2 queue + * vb2_discard_done() - discard all buffers marked as DONE. + * @q: pointer to &struct vb2_queue with videobuf2 queue. * * This function is intended to be used with suspend/resume operations. It * discards all 'done' buffers as they would be too old to be requested after @@ -615,132 +762,168 @@ void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state); void vb2_discard_done(struct vb2_queue *q); /** - * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2 - * @q: videobuf2 queue + * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2. + * @q: pointer to &struct vb2_queue with videobuf2 queue. * * This function will wait until all buffers that have been given to the driver * by &vb2_ops->buf_queue are given back to vb2 with vb2_buffer_done(). It - * doesn't call wait_prepare()/wait_finish() pair. It is intended to be called - * with all locks taken, for example from &vb2_ops->stop_streaming callback. + * doesn't call &vb2_ops->wait_prepare/&vb2_ops->wait_finish pair. + * It is intended to be called with all locks taken, for example from + * &vb2_ops->stop_streaming callback. */ int vb2_wait_for_all_buffers(struct vb2_queue *q); /** - * vb2_core_querybuf() - query video buffer information - * @q: videobuf queue - * @index: id number of the buffer - * @pb: buffer struct passed from userspace + * vb2_core_querybuf() - query video buffer information. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @vb: pointer to struct &vb2_buffer. + * @pb: buffer struct passed from userspace. + * + * Videobuf2 core helper to implement VIDIOC_QUERYBUF() operation. It is called + * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. * - * Should be called from vidioc_querybuf ioctl handler in driver. * The passed buffer should have been verified. + * * This function fills the relevant information for the userspace. + * + * Return: returns zero on success; an error code otherwise. */ -void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb); +void vb2_core_querybuf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb); /** - * vb2_core_reqbufs() - Initiate streaming - * @q: videobuf2 queue - * @memory: memory type - * @count: requested buffer count + * vb2_core_reqbufs() - Initiate streaming. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @memory: memory type, as defined by &enum vb2_memory. + * @flags: auxiliary queue/buffer management flags. Currently, the only + * used flag is %V4L2_MEMORY_FLAG_NON_COHERENT. + * @count: requested buffer count. * - * Should be called from vidioc_reqbufs ioctl handler of a driver. + * Videobuf2 core helper to implement VIDIOC_REQBUF() operation. It is called + * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. * * This function: * - * #) verifies streaming parameters passed from the userspace, - * #) sets up the queue, + * #) verifies streaming parameters passed from the userspace; + * #) sets up the queue; * #) negotiates number of buffers and planes per buffer with the driver - * to be used during streaming, - * #) allocates internal buffer structures (struct vb2_buffer), according to - * the agreed parameters, + * to be used during streaming; + * #) allocates internal buffer structures (&struct vb2_buffer), according to + * the agreed parameters; * #) for MMAP memory type, allocates actual video memory, using the - * memory handling/allocation routines provided during queue initialization + * memory handling/allocation routines provided during queue initialization. * * If req->count is 0, all the memory will be freed instead. - * If the queue has been allocated previously (by a previous vb2_reqbufs) call - * and the queue is not busy, memory will be reallocated. * - * The return values from this function are intended to be directly returned - * from vidioc_reqbufs handler in driver. + * If the queue has been allocated previously by a previous vb2_core_reqbufs() + * call and the queue is not busy, memory will be reallocated. + * + * Return: returns zero on success; an error code otherwise. */ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, - unsigned int *count); + unsigned int flags, unsigned int *count); /** * vb2_core_create_bufs() - Allocate buffers and any required auxiliary structs - * @q: videobuf2 queue - * @memory: memory type - * @count: requested buffer count - * @requested_planes: number of planes requested - * @requested_sizes: array with the size of the planes + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @memory: memory type, as defined by &enum vb2_memory. + * @flags: auxiliary queue/buffer management flags. + * @count: requested buffer count. + * @requested_planes: number of planes requested. + * @requested_sizes: array with the size of the planes. + * @first_index: index of the first created buffer, all allocated buffers have + * indices in the range [first_index..first_index+count-1] + * + * Videobuf2 core helper to implement VIDIOC_CREATE_BUFS() operation. It is + * called internally by VB2 by an API-specific handler, like + * ``videobuf2-v4l2.h``. * - * Should be called from VIDIOC_CREATE_BUFS() ioctl handler of a driver. * This function: * - * #) verifies parameter sanity - * #) calls the .queue_setup() queue operation - * #) performs any necessary memory allocations + * #) verifies parameter sanity; + * #) calls the &vb2_ops->queue_setup queue operation; + * #) performs any necessary memory allocations. * - * Return: the return values from this function are intended to be directly - * returned from VIDIOC_CREATE_BUFS() handler in driver. + * Return: returns zero on success; an error code otherwise. */ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, - unsigned int *count, unsigned int requested_planes, - const unsigned int requested_sizes[]); + unsigned int flags, unsigned int *count, + unsigned int requested_planes, + const unsigned int requested_sizes[], + unsigned int *first_index); /** * vb2_core_prepare_buf() - Pass ownership of a buffer from userspace - * to the kernel - * @q: videobuf2 queue - * @index: id number of the buffer - * @pb: buffer structure passed from userspace to vidioc_prepare_buf - * handler in driver + * to the kernel. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @vb: pointer to struct &vb2_buffer. + * @pb: buffer structure passed from userspace to + * &v4l2_ioctl_ops->vidioc_prepare_buf handler in driver. + * + * Videobuf2 core helper to implement VIDIOC_PREPARE_BUF() operation. It is + * called internally by VB2 by an API-specific handler, like + * ``videobuf2-v4l2.h``. * - * Should be called from vidioc_prepare_buf ioctl handler of a driver. * The passed buffer should have been verified. - * This function calls buf_prepare callback in the driver (if provided), - * in which driver-specific buffer initialization can be performed, * - * The return values from this function are intended to be directly returned - * from vidioc_prepare_buf handler in driver. + * This function calls vb2_ops->buf_prepare callback in the driver + * (if provided), in which driver-specific buffer initialization can + * be performed. + * + * Return: returns zero on success; an error code otherwise. + */ +int vb2_core_prepare_buf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb); + +/** + * vb2_core_remove_bufs() - + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @start: first index of the range of buffers to remove. + * @count: number of buffers to remove. + * + * Return: returns zero on success; an error code otherwise. */ -int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb); +int vb2_core_remove_bufs(struct vb2_queue *q, unsigned int start, unsigned int count); /** * vb2_core_qbuf() - Queue a buffer from userspace * - * @q: videobuf2 queue - * @index: id number of the buffer - * @pb: buffer structure passed from userspace to vidioc_qbuf handler - * in driver + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @vb: pointer to struct &vb2_buffer. + * @pb: buffer structure passed from userspace to + * v4l2_ioctl_ops->vidioc_qbuf handler in driver + * @req: pointer to &struct media_request, may be NULL. * - * Should be called from vidioc_qbuf ioctl handler of a driver. - * The passed buffer should have been verified. + * Videobuf2 core helper to implement VIDIOC_QBUF() operation. It is called + * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. * * This function: * - * #) if necessary, calls buf_prepare callback in the driver (if provided), in - * which driver-specific buffer initialization can be performed, + * #) If @req is non-NULL, then the buffer will be bound to this + * media request and it returns. The buffer will be prepared and + * queued to the driver (i.e. the next two steps) when the request + * itself is queued. + * #) if necessary, calls &vb2_ops->buf_prepare callback in the driver + * (if provided), in which driver-specific buffer initialization can + * be performed; * #) if streaming is on, queues the buffer in driver by the means of * &vb2_ops->buf_queue callback for processing. * - * The return values from this function are intended to be directly returned - * from vidioc_qbuf handler in driver. + * Return: returns zero on success; an error code otherwise. */ -int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb); +int vb2_core_qbuf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb, + struct media_request *req); /** * vb2_core_dqbuf() - Dequeue a buffer to the userspace - * @q: videobuf2 queue + * @q: pointer to &struct vb2_queue with videobuf2 queue * @pindex: pointer to the buffer index. May be NULL - * @pb: buffer structure passed from userspace to vidioc_dqbuf handler - * in driver + * @pb: buffer structure passed from userspace to + * v4l2_ioctl_ops->vidioc_dqbuf handler in driver. * @nonblocking: if true, this call will not sleep waiting for a buffer if no * buffers ready for dequeuing are present. Normally the driver - * would be passing (file->f_flags & O_NONBLOCK) here + * would be passing (file->f_flags & O_NONBLOCK) here. * - * Should be called from vidioc_dqbuf ioctl handler of a driver. - * The passed buffer should have been verified. + * Videobuf2 core helper to implement VIDIOC_DQBUF() operation. It is called + * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. * * This function: * @@ -750,73 +933,108 @@ int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb); * #) the buffer struct members are filled with relevant information for * the userspace. * - * The return values from this function are intended to be directly returned - * from vidioc_dqbuf handler in driver. + * Return: returns zero on success; an error code otherwise. */ int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb, bool nonblocking); +/** + * vb2_core_streamon() - Implements VB2 stream ON logic + * + * @q: pointer to &struct vb2_queue with videobuf2 queue + * @type: type of the queue to be started. + * For V4L2, this is defined by &enum v4l2_buf_type type. + * + * Videobuf2 core helper to implement VIDIOC_STREAMON() operation. It is called + * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. + * + * Return: returns zero on success; an error code otherwise. + */ int vb2_core_streamon(struct vb2_queue *q, unsigned int type); + +/** + * vb2_core_streamoff() - Implements VB2 stream OFF logic + * + * @q: pointer to &struct vb2_queue with videobuf2 queue + * @type: type of the queue to be started. + * For V4L2, this is defined by &enum v4l2_buf_type type. + * + * Videobuf2 core helper to implement VIDIOC_STREAMOFF() operation. It is + * called internally by VB2 by an API-specific handler, like + * ``videobuf2-v4l2.h``. + * + * Return: returns zero on success; an error code otherwise. + */ int vb2_core_streamoff(struct vb2_queue *q, unsigned int type); /** - * vb2_core_expbuf() - Export a buffer as a file descriptor - * @q: videobuf2 queue - * @fd: file descriptor associated with DMABUF (set by driver) * - * @type: buffer type - * @index: id number of the buffer + * vb2_core_expbuf() - Export a buffer as a file descriptor. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @fd: pointer to the file descriptor associated with DMABUF + * (set by driver). + * @type: buffer type. + * @vb: pointer to struct &vb2_buffer. * @plane: index of the plane to be exported, 0 for single plane queues - * @flags: flags for newly created file, currently only O_CLOEXEC is - * supported, refer to manual of open syscall for more details + * @flags: file flags for newly created file, as defined at + * include/uapi/asm-generic/fcntl.h. + * Currently, the only used flag is %O_CLOEXEC. + * is supported, refer to manual of open syscall for more details. * - * The return values from this function are intended to be directly returned - * from vidioc_expbuf handler in driver. + * + * Videobuf2 core helper to implement VIDIOC_EXPBUF() operation. It is called + * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. + * + * Return: returns zero on success; an error code otherwise. */ int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type, - unsigned int index, unsigned int plane, unsigned int flags); + struct vb2_buffer *vb, unsigned int plane, unsigned int flags); /** * vb2_core_queue_init() - initialize a videobuf2 queue - * @q: videobuf2 queue; this structure should be allocated in driver + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * This structure should be allocated in driver * - * The vb2_queue structure should be allocated by the driver. The driver is + * The &vb2_queue structure should be allocated by the driver. The driver is * responsible of clearing it's content and setting initial values for some * required entries before calling this function. - * q->ops, q->mem_ops, q->type and q->io_modes are mandatory. Please refer - * to the struct vb2_queue description in include/media/videobuf2-core.h - * for more information. + * + * .. note:: + * + * The following fields at @q should be set before calling this function: + * &vb2_queue->ops, &vb2_queue->mem_ops, &vb2_queue->type. */ int vb2_core_queue_init(struct vb2_queue *q); /** * vb2_core_queue_release() - stop streaming, release the queue and free memory - * @q: videobuf2 queue + * @q: pointer to &struct vb2_queue with videobuf2 queue. * * This function stops streaming and performs necessary clean ups, including * freeing video buffer memory. The driver is responsible for freeing - * the vb2_queue structure itself. + * the &struct vb2_queue itself. */ void vb2_core_queue_release(struct vb2_queue *q); /** * vb2_queue_error() - signal a fatal error on the queue - * @q: videobuf2 queue + * @q: pointer to &struct vb2_queue with videobuf2 queue. * * Flag that a fatal unrecoverable error has occurred and wake up all processes - * waiting on the queue. Polling will now set POLLERR and queuing and dequeuing - * buffers will return -EIO. + * waiting on the queue. Polling will now set %EPOLLERR and queuing and dequeuing + * buffers will return %-EIO. * - * The error flag will be cleared when cancelling the queue, either from - * vb2_streamoff or vb2_queue_release. Drivers should thus not call this + * The error flag will be cleared when canceling the queue, either from + * vb2_streamoff() or vb2_queue_release(). Drivers should thus not call this * function before starting the stream, otherwise the error flag will remain set * until the queue is released when closing the device node. */ void vb2_queue_error(struct vb2_queue *q); /** - * vb2_mmap() - map video buffers into application address space - * @q: videobuf2 queue - * @vma: vma passed to the mmap file operation handler in the driver + * vb2_mmap() - map video buffers into application address space. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @vma: pointer to &struct vm_area_struct with the vma passed + * to the mmap file operation handler in the driver. * * Should be called from mmap file operation handler of a driver. * This function maps one plane of one of the available video buffers to @@ -824,8 +1042,10 @@ void vb2_queue_error(struct vb2_queue *q); * has to be called once per each plane per each buffer previously allocated. * * When the userspace application calls mmap, it passes to it an offset returned - * to it earlier by the means of vidioc_querybuf handler. That offset acts as - * a "cookie", which is then used to identify the plane to be mapped. + * to it earlier by the means of &v4l2_ioctl_ops->vidioc_querybuf handler. + * That offset acts as a "cookie", which is then used to identify the plane + * to be mapped. + * * This function finds a plane with a matching offset and a mapping is performed * by the means of a provided memory operation. * @@ -835,6 +1055,21 @@ void vb2_queue_error(struct vb2_queue *q); int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma); #ifndef CONFIG_MMU +/** + * vb2_get_unmapped_area - map video buffers into application address space. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @addr: memory address. + * @len: buffer size. + * @pgoff: page offset. + * @flags: memory flags. + * + * This function is used in noMMU platforms to propose address mapping + * for a given buffer. It's intended to be used as a handler for the + * &file_operations->get_unmapped_area operation. + * + * This is called by the mmap() syscall routines will call this + * to get a proposed address for the mapping, when ``!CONFIG_MMU``. + */ unsigned long vb2_get_unmapped_area(struct vb2_queue *q, unsigned long addr, unsigned long len, @@ -843,10 +1078,12 @@ unsigned long vb2_get_unmapped_area(struct vb2_queue *q, #endif /** - * vb2_core_poll() - implements poll userspace operation - * @q: videobuf2 queue - * @file: file argument passed to the poll file operation handler - * @wait: wait argument passed to the poll file operation handler + * vb2_core_poll() - implements poll syscall() logic. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @file: &struct file argument passed to the poll + * file operation handler. + * @wait: &poll_table wait argument passed to the poll + * file operation handler. * * This function implements poll file operation handler for a driver. * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will @@ -858,19 +1095,35 @@ unsigned long vb2_get_unmapped_area(struct vb2_queue *q, * The return values from this function are intended to be directly returned * from poll handler in driver. */ -unsigned int vb2_core_poll(struct vb2_queue *q, struct file *file, +__poll_t vb2_core_poll(struct vb2_queue *q, struct file *file, poll_table *wait); +/** + * vb2_read() - implements read() syscall logic. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @data: pointed to target userspace buffer + * @count: number of bytes to read + * @ppos: file handle position tracking pointer + * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) + */ size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, loff_t *ppos, int nonblock); +/** + * vb2_write() - implements write() syscall logic. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @data: pointed to target userspace buffer + * @count: number of bytes to write + * @ppos: file handle position tracking pointer + * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) + */ size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, loff_t *ppos, int nonblock); /** - * typedef vb2_thread_fnc - callback function for use with vb2_thread + * typedef vb2_thread_fnc - callback function for use with vb2_thread. * - * @vb: pointer to struct &vb2_buffer - * @priv: pointer to a private pointer + * @vb: pointer to struct &vb2_buffer. + * @priv: pointer to a private data. * * This is called whenever a buffer is dequeued in the thread. */ @@ -878,13 +1131,13 @@ typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv); /** * vb2_thread_start() - start a thread for the given queue. - * @q: videobuf queue - * @fnc: callback function - * @priv: priv pointer passed to the callback function + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @fnc: &vb2_thread_fnc callback function. + * @priv: priv pointer passed to the callback function. * @thread_name:the name of the thread. This will be prefixed with "vb2-". * * This starts a thread that will queue and dequeue until an error occurs - * or @vb2_thread_stop is called. + * or vb2_thread_stop() is called. * * .. attention:: * @@ -897,13 +1150,13 @@ int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, /** * vb2_thread_stop() - stop the thread for the given queue. - * @q: videobuf queue + * @q: pointer to &struct vb2_queue with videobuf2 queue. */ int vb2_thread_stop(struct vb2_queue *q); /** - * vb2_is_streaming() - return streaming status of the queue - * @q: videobuf queue + * vb2_is_streaming() - return streaming status of the queue. + * @q: pointer to &struct vb2_queue with videobuf2 queue. */ static inline bool vb2_is_streaming(struct vb2_queue *q) { @@ -912,15 +1165,16 @@ static inline bool vb2_is_streaming(struct vb2_queue *q) /** * vb2_fileio_is_active() - return true if fileio is active. - * @q: videobuf queue + * @q: pointer to &struct vb2_queue with videobuf2 queue. * * This returns true if read() or write() is used to stream the data * as opposed to stream I/O. This is almost never an important distinction, * except in rare cases. One such case is that using read() or write() to - * stream a format using V4L2_FIELD_ALTERNATE is not allowed since there + * stream a format using %V4L2_FIELD_ALTERNATE is not allowed since there * is no way you can pass the field information of each buffer to/from * userspace. A driver that supports this field format should check for - * this in the queue_setup op and reject it if this function returns true. + * this in the &vb2_ops->queue_setup op and reject it if this function returns + * true. */ static inline bool vb2_fileio_is_active(struct vb2_queue *q) { @@ -928,19 +1182,31 @@ static inline bool vb2_fileio_is_active(struct vb2_queue *q) } /** - * vb2_is_busy() - return busy status of the queue - * @q: videobuf queue + * vb2_get_num_buffers() - get the number of buffer in a queue + * @q: pointer to &struct vb2_queue with videobuf2 queue. + */ +static inline unsigned int vb2_get_num_buffers(struct vb2_queue *q) +{ + if (q->bufs_bitmap) + return bitmap_weight(q->bufs_bitmap, q->max_num_buffers); + + return 0; +} + +/** + * vb2_is_busy() - return busy status of the queue. + * @q: pointer to &struct vb2_queue with videobuf2 queue. * * This function checks if queue has any buffers allocated. */ static inline bool vb2_is_busy(struct vb2_queue *q) { - return (q->num_buffers > 0); + return !!q->is_busy; } /** - * vb2_get_drv_priv() - return driver private data associated with the queue - * @q: videobuf queue + * vb2_get_drv_priv() - return driver private data associated with the queue. + * @q: pointer to &struct vb2_queue with videobuf2 queue. */ static inline void *vb2_get_drv_priv(struct vb2_queue *q) { @@ -948,22 +1214,31 @@ static inline void *vb2_get_drv_priv(struct vb2_queue *q) } /** - * vb2_set_plane_payload() - set bytesused for the plane plane_no - * @vb: buffer for which plane payload should be set - * @plane_no: plane number for which payload should be set - * @size: payload in bytes + * vb2_set_plane_payload() - set bytesused for the plane @plane_no. + * @vb: pointer to &struct vb2_buffer to which the plane in + * question belongs to. + * @plane_no: plane number for which payload should be set. + * @size: payload in bytes. */ static inline void vb2_set_plane_payload(struct vb2_buffer *vb, unsigned int plane_no, unsigned long size) { - if (plane_no < vb->num_planes) + /* + * size must never be larger than the buffer length, so + * warn and clamp to the buffer length if that's the case. + */ + if (plane_no < vb->num_planes) { + if (WARN_ON_ONCE(size > vb->planes[plane_no].length)) + size = vb->planes[plane_no].length; vb->planes[plane_no].bytesused = size; + } } /** * vb2_get_plane_payload() - get bytesused for the plane plane_no - * @vb: buffer for which plane payload should be set - * @plane_no: plane number for which payload should be set + * @vb: pointer to &struct vb2_buffer to which the plane in + * question belongs to. + * @plane_no: plane number for which payload should be set. */ static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb, unsigned int plane_no) @@ -974,9 +1249,10 @@ static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb, } /** - * vb2_plane_size() - return plane size in bytes - * @vb: buffer for which plane size should be returned - * @plane_no: plane number for which size should be returned + * vb2_plane_size() - return plane size in bytes. + * @vb: pointer to &struct vb2_buffer to which the plane in + * question belongs to. + * @plane_no: plane number for which size should be returned. */ static inline unsigned long vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no) @@ -987,8 +1263,8 @@ vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no) } /** - * vb2_start_streaming_called() - return streaming status of driver - * @q: videobuf queue + * vb2_start_streaming_called() - return streaming status of driver. + * @q: pointer to &struct vb2_queue with videobuf2 queue. */ static inline bool vb2_start_streaming_called(struct vb2_queue *q) { @@ -996,14 +1272,38 @@ static inline bool vb2_start_streaming_called(struct vb2_queue *q) } /** - * vb2_clear_last_buffer_dequeued() - clear last buffer dequeued flag of queue - * @q: videobuf queue + * vb2_clear_last_buffer_dequeued() - clear last buffer dequeued flag of queue. + * @q: pointer to &struct vb2_queue with videobuf2 queue. */ static inline void vb2_clear_last_buffer_dequeued(struct vb2_queue *q) { q->last_buffer_dequeued = false; } +/** + * vb2_get_buffer() - get a buffer from a queue + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @index: buffer index + * + * This function obtains a buffer from a queue, by its index. + * Keep in mind that there is no refcounting involved in this + * operation, so the buffer lifetime should be taken into + * consideration. + */ +static inline struct vb2_buffer *vb2_get_buffer(struct vb2_queue *q, + unsigned int index) +{ + if (!q->bufs) + return NULL; + + if (index >= q->max_num_buffers) + return NULL; + + if (test_bit(index, q->bufs_bitmap)) + return q->bufs[index]; + return NULL; +} + /* * The following functions are not part of the vb2 core API, but are useful * functions for videobuf2-*. @@ -1011,10 +1311,10 @@ static inline void vb2_clear_last_buffer_dequeued(struct vb2_queue *q) /** * vb2_buffer_in_use() - return true if the buffer is in use and - * the queue cannot be freed (by the means of REQBUFS(0)) call + * the queue cannot be freed (by the means of VIDIOC_REQBUFS(0)) call. * - * @vb: buffer for which plane size should be returned - * @q: videobuf queue + * @vb: buffer for which plane size should be returned. + * @q: pointer to &struct vb2_queue with videobuf2 queue. */ bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb); @@ -1022,12 +1322,27 @@ bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb); * vb2_verify_memory_type() - Check whether the memory type and buffer type * passed to a buffer operation are compatible with the queue. * - * @q: videobuf queue + * @q: pointer to &struct vb2_queue with videobuf2 queue. * @memory: memory model, as defined by enum &vb2_memory. * @type: private buffer type whose content is defined by the vb2-core * caller. For example, for V4L2, it should match - * the types defined on enum &v4l2_buf_type + * the types defined on enum &v4l2_buf_type. */ int vb2_verify_memory_type(struct vb2_queue *q, enum vb2_memory memory, unsigned int type); + +/** + * vb2_request_object_is_buffer() - return true if the object is a buffer + * + * @obj: the request object. + */ +bool vb2_request_object_is_buffer(struct media_request_object *obj); + +/** + * vb2_request_buffer_cnt() - return the number of buffers in the request + * + * @req: the request. + */ +unsigned int vb2_request_buffer_cnt(struct media_request *req); + #endif /* _MEDIA_VIDEOBUF2_CORE_H */ |