diff options
Diffstat (limited to 'include/media/videobuf2-core.h')
| -rw-r--r-- | include/media/videobuf2-core.h | 1332 |
1 files changed, 1087 insertions, 245 deletions
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index d88a098d1aff..9b02aeba4108 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -1,5 +1,5 @@ /* - * videobuf2-core.h - V4L2 driver helper framework + * videobuf2-core.h - Video Buffer 2 Core Framework * * Copyright (C) 2010 Samsung Electronics * @@ -15,146 +15,218 @@ #include <linux/mm_types.h> #include <linux/mutex.h> #include <linux/poll.h> -#include <linux/videodev2.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) + +/** + * enum vb2_memory - type of memory model used to make the buffers visible + * on userspace. + * + * @VB2_MEMORY_UNKNOWN: Buffer status is unknown or it is not used yet on + * userspace. + * @VB2_MEMORY_MMAP: The buffers are allocated by the Kernel and it is + * memory mapped via mmap() ioctl. This model is + * also used when the user is using the buffers via + * read() or write() system calls. + * @VB2_MEMORY_USERPTR: The buffers was allocated in userspace and it is + * memory mapped via mmap() ioctl. + * @VB2_MEMORY_DMABUF: The buffers are passed to userspace via DMA buffer. + */ +enum vb2_memory { + VB2_MEMORY_UNKNOWN = 0, + VB2_MEMORY_MMAP = 1, + VB2_MEMORY_USERPTR = 2, + VB2_MEMORY_DMABUF = 4, +}; -struct vb2_alloc_ctx; 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 NULL on failure or a pointer to allocator private, + * 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. + * will then be passed as @buf_priv argument to other ops in this + * 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 + * no other users of this buffer are present); the @buf_priv * argument is the allocator private per-buffer structure - * previously returned from the alloc callback + * previously returned from the alloc callback. + * @get_dmabuf: acquire userspace memory for a hardware operation; used for + * 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, NULL on failure; - * the returned private structure will then be passed as buf_priv - * argument to other ops in this 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; - * used for DMABUF memory types; alloc_ctx is the alloc context - * dbuf is the shared dma_buf; returns NULL on failure; + * be used. + * @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; - * this needs to be used for further accesses to the buffer + * this needs to be used for further accesses to the buffer. * @detach_dmabuf: inform the exporter of the buffer that the current DMABUF - * buffer is no longer used; the buf_priv argument is the + * buffer is no longer used; the @buf_priv argument is the * allocator private per-buffer structure previously returned - * from the attach_dmabuf callback + * from the attach_dmabuf callback. * @map_dmabuf: request for access to the dmabuf from allocator; the allocator * of dmabuf is informed that this driver is going to use the - * dmabuf + * 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 + * that this driver is done using the dmabuf for now. * @vaddr: return a kernel virtual address to a given memory buffer * associated with the passed private structure or NULL if no - * such mapping exists + * such mapping exists. * @cookie: return allocator specific cookie for a given memory buffer * associated with the passed private structure or NULL if not - * available + * available. * @num_users: return the current number of users of a memory buffer; - * return 1 if the videobuf layer (or actually the driver using - * it) is the only user + * 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 + * the provided virtual memory region. + * + * Those operations are used by the videobuf2 core to implement the memory + * handling/memory allocators for each type of supported streaming I/O method. + * + * .. note:: + * #) Required ops for USERPTR types: get_userptr, put_userptr. * - * Required ops for USERPTR types: get_userptr, put_userptr. - * Required ops for MMAP types: alloc, put, num_users, mmap. - * Required ops for read/write access types: alloc, put, num_users, vaddr - * Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, map_dmabuf, - * unmap_dmabuf. + * #) Required ops for MMAP types: alloc, put, num_users, mmap. + * + * #) Required ops for read/write access types: alloc, put, num_users, vaddr. + * + * #) Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, + * map_dmabuf, unmap_dmabuf. */ struct vb2_mem_ops { - void *(*alloc)(void *alloc_ctx, unsigned long size, 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); + struct dma_buf *(*get_dmabuf)(struct vb2_buffer *vb, + void *buf_priv, + unsigned long flags); - void *(*get_userptr)(void *alloc_ctx, unsigned long vaddr, - unsigned long size, int write); + 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)(void *alloc_ctx, struct dma_buf *dbuf, - unsigned long size, int write); + void *(*attach_dmabuf)(struct vb2_buffer *vb, + struct device *dev, + struct dma_buf *dbuf, + 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); int (*mmap)(void *buf_priv, struct vm_area_struct *vma); }; +/** + * 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 + * @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, 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). + * @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. + * + * Should contain enough information to be able to cover all the fields + * 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; + union { + unsigned int offset; + unsigned long userptr; + int fd; + } m; + unsigned int data_offset; }; /** - * 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_fileio_flags - flags for selecting a mode of the file io emulator, - * by default the 'streaming' style is used by the file io emulator - * @VB2_FILEIO_READ_ONCE: report EOF after reading the first buffer - * @VB2_FILEIO_WRITE_IMMEDIATELY: queue buffer after each write() call - */ -enum vb2_fileio_flags { - VB2_FILEIO_READ_ONCE = (1 << 0), - VB2_FILEIO_WRITE_IMMEDIATELY = (1 << 1), -}; - -/** - * enum vb2_buffer_state - current video buffer state - * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control - * @VB2_BUF_STATE_PREPARED: buffer prepared in videobuf and by the driver - * @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in 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_PREPARED, + VB2_BUF_STATE_IN_REQUEST, + VB2_BUF_STATE_PREPARING, VB2_BUF_STATE_QUEUED, VB2_BUF_STATE_ACTIVE, VB2_BUF_STATE_DONE, @@ -164,132 +236,291 @@ enum vb2_buffer_state { struct vb2_queue; /** - * struct vb2_buffer - represents a video buffer - * @v4l2_buf: struct v4l2_buffer associated with this buffer; can - * be read by the driver and relevant entries can be - * changed by the driver in case of CAPTURE types - * (such as timestamp) - * @v4l2_planes: struct v4l2_planes associated with this buffer; can - * be read by the driver and relevant entries can be - * changed by the driver in case of CAPTURE types - * (such as bytesused); NOTE that even for single-planar - * types, the v4l2_planes[0] struct should be used - * instead of v4l2_buf for filling bytesused - drivers - * should use the vb2_set_plane_payload() function for that - * @vb2_queue: the queue to which this driver belongs + * 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 - * @state: current buffer state; 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 - * @planes: private per-plane information; do not change + * 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 v4l2_buffer v4l2_buf; - struct v4l2_plane v4l2_planes[VIDEO_MAX_PLANES]; - struct vb2_queue *vb2_queue; - + unsigned int index; + unsigned int type; + unsigned int memory; unsigned int num_planes; + u64 timestamp; + struct media_request *request; + struct media_request_object req_obj; -/* Private: internal use only */ + /* 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 + /* + * Counters for how often these buffer-related ops are + * called. Used to check for unbalanced ops. + */ + u32 cnt_mem_alloc; + u32 cnt_mem_put; + u32 cnt_mem_get_dmabuf; + u32 cnt_mem_get_userptr; + u32 cnt_mem_put_userptr; + u32 cnt_mem_prepare; + u32 cnt_mem_finish; + u32 cnt_mem_attach_dmabuf; + u32 cnt_mem_detach_dmabuf; + u32 cnt_mem_map_dmabuf; + u32 cnt_mem_unmap_dmabuf; + u32 cnt_mem_vaddr; + u32 cnt_mem_cookie; + 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; - struct vb2_plane planes[VIDEO_MAX_PLANES]; + /* This counts the number of calls to vb2_buffer_done() */ + u32 cnt_buf_done; +#endif }; /** - * struct vb2_ops - driver-specific callbacks - * - * @queue_setup: called from VIDIOC_REQBUFS and VIDIOC_CREATE_BUFS - * handlers before memory allocation, or, if - * *num_planes != 0, after the allocation to verify a - * smaller number of buffers. Driver should return - * the required number of buffers in *num_buffers, the - * required number of planes per buffer in *num_planes; the - * size of each plane should be set in the sizes[] array - * and optional per-plane allocator specific context in the - * alloc_ctxs[] array. When called from VIDIOC_REQBUFS, - * fmt == NULL, the driver has to use the currently - * configured format and *num_buffers is the total number - * of buffers, that are being allocated. When called from - * VIDIOC_CREATE_BUFS, fmt != NULL and it describes the - * target frame format. In this case *num_buffers are being - * allocated additionally to q->num_buffers. + * 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 + * twice: if the original number of requested buffers + * could not be allocated, then it will be called a + * second time with the actually allocated number of + * buffers to verify if that is OK. + * The driver should return the required number of buffers + * in \*num_buffers, the required number of planes per + * buffer in \*num_planes, the size of each plane should be + * set in the sizes\[\] array and optional per-plane + * allocator specific device in the alloc_devs\[\] array. + * When called from VIDIOC_REQBUFS(), \*num_planes == 0, + * the driver has to use the currently configured format to + * determine the plane sizes and \*num_buffers is the total + * number of buffers that are being allocated. When called + * from VIDIOC_CREATE_BUFS(), \*num_planes != 0 and it + * describes the requested number of planes and sizes\[\] + * contains the requested plane sizes. In this case + * \*num_buffers are being allocated additionally to + * 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 - * blocking access type + * blocking access type. * @wait_finish: reacquire all locks released in the previous callback; * required to continue operation after sleeping while - * waiting for a new buffer to arrive + * 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; * initialization failure (return != 0) will prevent - * queue setup from completing successfully; optional + * queue setup from completing successfully; optional. * @buf_prepare: called every time the buffer is queued from userspace - * and from the VIDIOC_PREPARE_BUF ioctl; drivers may - * perform any initialization required before each hardware - * operation in this callback; if an error is returned, the - * buffer will not be queued in driver; optional + * and from the VIDIOC_PREPARE_BUF() ioctl; drivers may + * perform any initialization required before each + * hardware operation in this callback; drivers can + * access/modify the buffer here as it is still synced for + * the CPU; drivers that support VIDIOC_CREATE_BUFS() must + * also validate the buffer size; if an error is returned, + * the buffer will not be queued in driver; optional. * @buf_finish: called before every dequeue of the buffer back to - * userspace; drivers may perform any operations required - * before userspace accesses the buffer; optional + * userspace; the buffer is synced for the CPU, so drivers + * can access/modify the buffer contents; drivers may + * perform any operations required before userspace + * accesses the buffer; optional. The buffer state can be + * one of the following: %DONE and %ERROR occur while + * streaming is in progress, and the %PREPARED state occurs + * when the queue has been canceled and all pending + * buffers are being returned to their default %DEQUEUED + * state. Typically you only have to do something if the + * state is %VB2_BUF_STATE_DONE, since in all other cases + * the buffer contents will be ignored anyway. * @buf_cleanup: called once before the buffer is freed; drivers may - * perform any additional cleanup; optional + * 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 number - * of already queued buffers in count parameter; driver - * can return an error if hardware fails or not enough - * buffers has been queued, in such case all buffers that - * have been already given by the @buf_queue callback are - * invalidated. + * receive buffers with @buf_queue callback + * before @start_streaming is called; the driver gets the + * number of already queued buffers in count parameter; + * driver can return an error if hardware fails, in that + * case all buffers that have been already given by + * 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 + * &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; may use vb2_wait_for_all_buffers() function + * 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 STREAMON ioctl; - * might be called before start_streaming callback if user - * pre-queued buffers before calling 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, const struct v4l2_format *fmt, + int (*queue_setup)(struct vb2_queue *q, unsigned int *num_buffers, unsigned int *num_planes, - unsigned int sizes[], void *alloc_ctxs[]); + unsigned int sizes[], struct device *alloc_devs[]); 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); - int (*buf_finish)(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); - int (*stop_streaming)(struct vb2_queue *q); + 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 v4l2_fh; +/** + * 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. + * @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 &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, 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: queue type (see V4L2_BUF_TYPE_* in linux/videodev2.h - * @io_modes: supported io methods (see vb2_io_modes enum) - * @io_flags: additional io flags (see vb2_fileio_flags enum) - * @lock: pointer to a mutex that protects the vb2_queue struct. The + * @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 &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 %EPOLLERR at poll when QBUF + * has not been called. This is a vb1 idiom that has been adopted + * also by vb2. + * @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 @@ -300,100 +531,632 @@ struct v4l2_fh; * drivers to easily associate an owner filehandle with the queue. * @ops: driver-specific callbacks * @mem_ops: memory allocator specific callbacks - * @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, so sizeof(struct vb2_buffer) will is used + * 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_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 owned by the driver + * @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_ctx: memory type/allocator-specific contexts for each plane * @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 %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. * @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 { - enum v4l2_buf_type type; + unsigned int type; unsigned int io_modes; - unsigned int io_flags; + struct device *dev; + unsigned long dma_attrs; + 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; - struct v4l2_fh *owner; + void *owner; const struct vb2_ops *ops; const struct vb2_mem_ops *mem_ops; + const struct vb2_buf_ops *buf_ops; + void *drv_priv; + u32 subsystem_flags; unsigned int buf_struct_size; - u32 timestamp_type; + u32 timestamp_flags; gfp_t gfp_flags; + u32 min_queued_buffers; + u32 min_reqbufs_allocation; + + struct device *alloc_devs[VB2_MAX_PLANES]; -/* private: internal use only */ - enum v4l2_memory memory; - struct vb2_buffer *bufs[VIDEO_MAX_FRAME]; - unsigned int num_buffers; + /* private: internal use only */ + struct mutex mmap_lock; + unsigned int memory; + 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; - atomic_t queued_count; + atomic_t owned_by_drv_count; struct list_head done_list; spinlock_t done_lock; wait_queue_head_t done_wq; - void *alloc_ctx[VIDEO_MAX_PLANES]; - unsigned int plane_sizes[VIDEO_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 + * called. Used to check for unbalanced ops. + */ + 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_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. + */ void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no); + +/** + * 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 + * inline function, which would convert this cookie to the allocator specific + * type that can be used directly by the driver to access the buffer. This can + * be for example physical address, pointer to scatter list or IOMMU mapping. + */ void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no); +/** + * 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. + * + * 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 + * cannot use this buffer anymore until it is queued back to it by videobuf + * by the means of &vb2_ops->buf_queue callback. Only buffers previously queued + * 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 &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: 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 + * resume. + * + * Drivers must stop the hardware and synchronize with interrupt handlers and/or + * delayed works before calling this function to make sure no buffer will be + * touched by the driver and/or hardware. + */ +void vb2_discard_done(struct vb2_queue *q); + +/** + * 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 &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); -int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b); -int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req); +/** + * 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``. + * + * 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, struct vb2_buffer *vb, void *pb); + +/** + * 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. + * + * 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; + * #) 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; + * #) for MMAP memory type, allocates actual video memory, using the + * 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_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 flags, unsigned int *count); + +/** + * vb2_core_create_bufs() - Allocate buffers and any required auxiliary structs + * @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``. + * + * This function: + * + * #) verifies parameter sanity; + * #) calls the &vb2_ops->queue_setup queue operation; + * #) performs any necessary memory allocations. + * + * Return: returns zero on success; an error code otherwise. + */ +int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, + 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: 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``. + * + * The passed buffer should have been verified. + * + * 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_remove_bufs(struct vb2_queue *q, unsigned int start, unsigned int count); + +/** + * vb2_core_qbuf() - Queue a buffer from userspace + * + * @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. + * + * 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 @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. + * + * Return: returns zero on success; an error code otherwise. + */ +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: pointer to &struct vb2_queue with videobuf2 queue + * @pindex: pointer to the buffer index. May be NULL + * @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. + * + * 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: + * + * #) calls buf_finish callback in the driver (if provided), in which + * driver can perform any additional operations that may be required before + * returning the buffer to userspace, such as cache sync, + * #) the buffer struct members are filled with relevant information for + * the userspace. + * + * 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); -int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create); -int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b); +/** + * 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); -int __must_check vb2_queue_init(struct vb2_queue *q); +/** + * 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: 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. + * + * + * 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, + struct vb2_buffer *vb, unsigned int plane, unsigned int flags); -void vb2_queue_release(struct vb2_queue *q); +/** + * vb2_core_queue_init() - initialize a videobuf2 queue + * @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 + * responsible of clearing it's content and setting initial values for some + * required entries before calling this function. + * + * .. 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); -int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b); -int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb); -int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking); +/** + * vb2_core_queue_release() - stop streaming, release the queue and free memory + * @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 &struct vb2_queue itself. + */ +void vb2_core_queue_release(struct vb2_queue *q); -int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type); -int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type); +/** + * vb2_queue_error() - signal a fatal error on the 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 %EPOLLERR and queuing and dequeuing + * buffers will return %-EIO. + * + * 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: 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 + * userspace. To map whole video memory allocated on reqbufs, this function + * 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 &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. + * + * The return values from this function are intended to be directly returned + * from the mmap handler in driver. + */ 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, unsigned long pgoff, unsigned long flags); #endif -unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait); + +/** + * 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 + * be informed that the file descriptor of a video device is available for + * reading. + * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor + * will be reported as available for writing. + * + * The return values from this function are intended to be directly returned + * from poll handler in driver. + */ +__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); -size_t vb2_write(struct vb2_queue *q, char __user *data, size_t count, +/** + * 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); /** - * vb2_is_streaming() - return streaming status of the queue - * @q: videobuf queue + * typedef vb2_thread_fnc - callback function for use with vb2_thread. + * + * @vb: pointer to struct &vb2_buffer. + * @priv: pointer to a private data. + * + * This is called whenever a buffer is dequeued in the thread. + */ +typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv); + +/** + * vb2_thread_start() - start a thread for the given queue. + * @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. + * + * .. attention:: + * + * This function should not be used for anything else but the videobuf2-dvb + * support. If you think you have another good use-case for this, then please + * contact the linux-media mailing list first. + */ +int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, + const char *thread_name); + +/** + * vb2_thread_stop() - stop the thread for the given 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: pointer to &struct vb2_queue with videobuf2 queue. */ static inline bool vb2_is_streaming(struct vb2_queue *q) { @@ -401,19 +1164,49 @@ static inline bool vb2_is_streaming(struct vb2_queue *q) } /** - * vb2_is_busy() - return busy status of the queue - * @q: videobuf queue + * vb2_fileio_is_active() - return true if fileio is active. + * @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 + * 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 &vb2_ops->queue_setup op and reject it if this function returns + * true. + */ +static inline bool vb2_fileio_is_active(struct vb2_queue *q) +{ + return q->fileio; +} + +/** + * 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) { @@ -421,86 +1214,135 @@ 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) - vb->v4l2_planes[plane_no].bytesused = size; + /* + * 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 - * @size: payload in bytes + * @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) { if (plane_no < vb->num_planes) - return vb->v4l2_planes[plane_no].bytesused; + return vb->planes[plane_no].bytesused; return 0; } /** - * 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) { if (plane_no < vb->num_planes) - return vb->v4l2_planes[plane_no].length; + return vb->planes[plane_no].length; return 0; } +/** + * 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) +{ + return q->start_streaming_called; +} + +/** + * 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 simple - * helper functions that you can use in your struct v4l2_file_operations, - * struct v4l2_ioctl_ops and struct vb2_ops. They will serialize if vb2_queue->lock - * or video_device->lock is set, and they will set and test vb2_queue->owner - * to check if the calling filehandle is permitted to do the queuing operation. - */ - -/* struct v4l2_ioctl_ops helpers */ - -int vb2_ioctl_reqbufs(struct file *file, void *priv, - struct v4l2_requestbuffers *p); -int vb2_ioctl_create_bufs(struct file *file, void *priv, - struct v4l2_create_buffers *p); -int vb2_ioctl_prepare_buf(struct file *file, void *priv, - struct v4l2_buffer *p); -int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p); -int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p); -int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p); -int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i); -int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i); -int vb2_ioctl_expbuf(struct file *file, void *priv, - struct v4l2_exportbuffer *p); - -/* struct v4l2_file_operations helpers */ - -int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma); -int vb2_fop_release(struct file *file); -ssize_t vb2_fop_write(struct file *file, char __user *buf, - size_t count, loff_t *ppos); -ssize_t vb2_fop_read(struct file *file, char __user *buf, - size_t count, loff_t *ppos); -unsigned int vb2_fop_poll(struct file *file, poll_table *wait); -#ifndef CONFIG_MMU -unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr, - unsigned long len, unsigned long pgoff, unsigned long flags); -#endif + * The following functions are not part of the vb2 core API, but are useful + * functions for videobuf2-*. + */ -/* struct vb2_ops helpers, only use if vq->lock is non-NULL. */ +/** + * vb2_buffer_in_use() - return true if the buffer is in use and + * the queue cannot be freed (by the means of VIDIOC_REQBUFS(0)) call. + * + * @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); + +/** + * vb2_verify_memory_type() - Check whether the memory type and buffer type + * passed to a buffer operation are compatible with the 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. + */ +int vb2_verify_memory_type(struct vb2_queue *q, + enum vb2_memory memory, unsigned int type); -void vb2_ops_wait_prepare(struct vb2_queue *vq); -void vb2_ops_wait_finish(struct vb2_queue *vq); +/** + * 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 */ |