diff options
Diffstat (limited to 'drivers/media/video/uvc/uvc_queue.c')
-rw-r--r-- | drivers/media/video/uvc/uvc_queue.c | 564 |
1 files changed, 153 insertions, 411 deletions
diff --git a/drivers/media/video/uvc/uvc_queue.c b/drivers/media/video/uvc/uvc_queue.c index 677691c4450..518f77d3a4d 100644 --- a/drivers/media/video/uvc/uvc_queue.c +++ b/drivers/media/video/uvc/uvc_queue.c @@ -11,6 +11,7 @@ * */ +#include <linux/atomic.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/list.h> @@ -19,7 +20,7 @@ #include <linux/videodev2.h> #include <linux/vmalloc.h> #include <linux/wait.h> -#include <linux/atomic.h> +#include <media/videobuf2-vmalloc.h> #include "uvcvideo.h" @@ -29,467 +30,211 @@ * Video queues is initialized by uvc_queue_init(). The function performs * basic initialization of the uvc_video_queue struct and never fails. * - * Video buffer allocation and freeing are performed by uvc_alloc_buffers and - * uvc_free_buffers respectively. The former acquires the video queue lock, - * while the later must be called with the lock held (so that allocation can - * free previously allocated buffers). Trying to free buffers that are mapped - * to user space will return -EBUSY. - * - * Video buffers are managed using two queues. However, unlike most USB video - * drivers that use an in queue and an out queue, we use a main queue to hold - * all queued buffers (both 'empty' and 'done' buffers), and an irq queue to - * hold empty buffers. This design (copied from video-buf) minimizes locking - * in interrupt, as only one queue is shared between interrupt and user - * contexts. - * - * Use cases - * --------- - * - * Unless stated otherwise, all operations that modify the irq buffers queue - * are protected by the irq spinlock. - * - * 1. The user queues the buffers, starts streaming and dequeues a buffer. - * - * The buffers are added to the main and irq queues. Both operations are - * protected by the queue lock, and the later is protected by the irq - * spinlock as well. - * - * The completion handler fetches a buffer from the irq queue and fills it - * with video data. If no buffer is available (irq queue empty), the handler - * returns immediately. - * - * When the buffer is full, the completion handler removes it from the irq - * queue, marks it as done (UVC_BUF_STATE_DONE) and wakes its wait queue. - * At that point, any process waiting on the buffer will be woken up. If a - * process tries to dequeue a buffer after it has been marked done, the - * dequeing will succeed immediately. - * - * 2. Buffers are queued, user is waiting on a buffer and the device gets - * disconnected. - * - * When the device is disconnected, the kernel calls the completion handler - * with an appropriate status code. The handler marks all buffers in the - * irq queue as being erroneous (UVC_BUF_STATE_ERROR) and wakes them up so - * that any process waiting on a buffer gets woken up. - * - * Waking up up the first buffer on the irq list is not enough, as the - * process waiting on the buffer might restart the dequeue operation - * immediately. - * + * Video buffers are managed by videobuf2. The driver uses a mutex to protect + * the videobuf2 queue operations by serializing calls to videobuf2 and a + * spinlock to protect the IRQ queue that holds the buffers to be processed by + * the driver. */ -void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type, - int drop_corrupted) -{ - mutex_init(&queue->mutex); - spin_lock_init(&queue->irqlock); - INIT_LIST_HEAD(&queue->mainqueue); - INIT_LIST_HEAD(&queue->irqqueue); - queue->flags = drop_corrupted ? UVC_QUEUE_DROP_CORRUPTED : 0; - queue->type = type; -} - -/* - * Free the video buffers. - * - * This function must be called with the queue lock held. +/* ----------------------------------------------------------------------------- + * videobuf2 queue operations */ -static int __uvc_free_buffers(struct uvc_video_queue *queue) + +static int uvc_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt, + unsigned int *nbuffers, unsigned int *nplanes, + unsigned int sizes[], void *alloc_ctxs[]) { - unsigned int i; + struct uvc_video_queue *queue = vb2_get_drv_priv(vq); + struct uvc_streaming *stream = + container_of(queue, struct uvc_streaming, queue); - for (i = 0; i < queue->count; ++i) { - if (queue->buffer[i].vma_use_count != 0) - return -EBUSY; - } + if (*nbuffers > UVC_MAX_VIDEO_BUFFERS) + *nbuffers = UVC_MAX_VIDEO_BUFFERS; - if (queue->count) { - uvc_queue_cancel(queue, 0); - INIT_LIST_HEAD(&queue->mainqueue); - vfree(queue->mem); - queue->count = 0; - } + *nplanes = 1; + + sizes[0] = stream->ctrl.dwMaxVideoFrameSize; return 0; } -int uvc_free_buffers(struct uvc_video_queue *queue) +static int uvc_buffer_prepare(struct vb2_buffer *vb) { - int ret; + struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); + struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); - mutex_lock(&queue->mutex); - ret = __uvc_free_buffers(queue); - mutex_unlock(&queue->mutex); + if (vb->v4l2_buf.type == V4L2_BUF_TYPE_VIDEO_OUTPUT && + vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0)) { + uvc_trace(UVC_TRACE_CAPTURE, "[E] Bytes used out of bounds.\n"); + return -EINVAL; + } - return ret; -} + if (unlikely(queue->flags & UVC_QUEUE_DISCONNECTED)) + return -ENODEV; -/* - * Allocate the video buffers. - * - * Pages are reserved to make sure they will not be swapped, as they will be - * filled in the URB completion handler. - * - * Buffers will be individually mapped, so they must all be page aligned. - */ -int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers, - unsigned int buflength) -{ - unsigned int bufsize = PAGE_ALIGN(buflength); - unsigned int i; - void *mem = NULL; - int ret; + buf->state = UVC_BUF_STATE_QUEUED; + buf->error = 0; + buf->mem = vb2_plane_vaddr(vb, 0); + buf->length = vb2_plane_size(vb, 0); + if (vb->v4l2_buf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE) + buf->bytesused = 0; + else + buf->bytesused = vb2_get_plane_payload(vb, 0); - if (nbuffers > UVC_MAX_VIDEO_BUFFERS) - nbuffers = UVC_MAX_VIDEO_BUFFERS; + return 0; +} - mutex_lock(&queue->mutex); +static void uvc_buffer_queue(struct vb2_buffer *vb) +{ + struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); + struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); + unsigned long flags; - if ((ret = __uvc_free_buffers(queue)) < 0) - goto done; + spin_lock_irqsave(&queue->irqlock, flags); + if (likely(!(queue->flags & UVC_QUEUE_DISCONNECTED))) { + list_add_tail(&buf->queue, &queue->irqqueue); + } else { + /* If the device is disconnected return the buffer to userspace + * directly. The next QBUF call will fail with -ENODEV. + */ + buf->state = UVC_BUF_STATE_ERROR; + vb2_buffer_done(&buf->buf, VB2_BUF_STATE_ERROR); + } - /* Bail out if no buffers should be allocated. */ - if (nbuffers == 0) - goto done; + spin_unlock_irqrestore(&queue->irqlock, flags); +} - /* Decrement the number of buffers until allocation succeeds. */ - for (; nbuffers > 0; --nbuffers) { - mem = vmalloc_32(nbuffers * bufsize); - if (mem != NULL) - break; - } +static int uvc_buffer_finish(struct vb2_buffer *vb) +{ + struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); + struct uvc_streaming *stream = + container_of(queue, struct uvc_streaming, queue); + struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); - if (mem == NULL) { - ret = -ENOMEM; - goto done; - } + uvc_video_clock_update(stream, &vb->v4l2_buf, buf); + return 0; +} - for (i = 0; i < nbuffers; ++i) { - memset(&queue->buffer[i], 0, sizeof queue->buffer[i]); - queue->buffer[i].buf.index = i; - queue->buffer[i].buf.m.offset = i * bufsize; - queue->buffer[i].buf.length = buflength; - queue->buffer[i].buf.type = queue->type; - queue->buffer[i].buf.field = V4L2_FIELD_NONE; - queue->buffer[i].buf.memory = V4L2_MEMORY_MMAP; - queue->buffer[i].buf.flags = 0; - init_waitqueue_head(&queue->buffer[i].wait); - } +static struct vb2_ops uvc_queue_qops = { + .queue_setup = uvc_queue_setup, + .buf_prepare = uvc_buffer_prepare, + .buf_queue = uvc_buffer_queue, + .buf_finish = uvc_buffer_finish, +}; - queue->mem = mem; - queue->count = nbuffers; - queue->buf_size = bufsize; - ret = nbuffers; +void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type, + int drop_corrupted) +{ + queue->queue.type = type; + queue->queue.io_modes = VB2_MMAP; + queue->queue.drv_priv = queue; + queue->queue.buf_struct_size = sizeof(struct uvc_buffer); + queue->queue.ops = &uvc_queue_qops; + queue->queue.mem_ops = &vb2_vmalloc_memops; + vb2_queue_init(&queue->queue); -done: - mutex_unlock(&queue->mutex); - return ret; + mutex_init(&queue->mutex); + spin_lock_init(&queue->irqlock); + INIT_LIST_HEAD(&queue->irqqueue); + queue->flags = drop_corrupted ? UVC_QUEUE_DROP_CORRUPTED : 0; } -/* - * Check if buffers have been allocated. +/* ----------------------------------------------------------------------------- + * V4L2 queue operations */ -int uvc_queue_allocated(struct uvc_video_queue *queue) + +int uvc_alloc_buffers(struct uvc_video_queue *queue, + struct v4l2_requestbuffers *rb) { - int allocated; + int ret; mutex_lock(&queue->mutex); - allocated = queue->count != 0; + ret = vb2_reqbufs(&queue->queue, rb); mutex_unlock(&queue->mutex); - return allocated; + return ret ? ret : rb->count; } -static void __uvc_query_buffer(struct uvc_buffer *buf, - struct v4l2_buffer *v4l2_buf) +void uvc_free_buffers(struct uvc_video_queue *queue) { - memcpy(v4l2_buf, &buf->buf, sizeof *v4l2_buf); - - if (buf->vma_use_count) - v4l2_buf->flags |= V4L2_BUF_FLAG_MAPPED; - - switch (buf->state) { - case UVC_BUF_STATE_ERROR: - case UVC_BUF_STATE_DONE: - v4l2_buf->flags |= V4L2_BUF_FLAG_DONE; - break; - case UVC_BUF_STATE_QUEUED: - case UVC_BUF_STATE_ACTIVE: - case UVC_BUF_STATE_READY: - v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED; - break; - case UVC_BUF_STATE_IDLE: - default: - break; - } + mutex_lock(&queue->mutex); + vb2_queue_release(&queue->queue); + mutex_unlock(&queue->mutex); } -int uvc_query_buffer(struct uvc_video_queue *queue, - struct v4l2_buffer *v4l2_buf) +int uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf) { - int ret = 0; + int ret; mutex_lock(&queue->mutex); - if (v4l2_buf->index >= queue->count) { - ret = -EINVAL; - goto done; - } - - __uvc_query_buffer(&queue->buffer[v4l2_buf->index], v4l2_buf); - -done: + ret = vb2_querybuf(&queue->queue, buf); mutex_unlock(&queue->mutex); + return ret; } -/* - * Queue a video buffer. Attempting to queue a buffer that has already been - * queued will return -EINVAL. - */ -int uvc_queue_buffer(struct uvc_video_queue *queue, - struct v4l2_buffer *v4l2_buf) +int uvc_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf) { - struct uvc_buffer *buf; - unsigned long flags; - int ret = 0; - - uvc_trace(UVC_TRACE_CAPTURE, "Queuing buffer %u.\n", v4l2_buf->index); - - if (v4l2_buf->type != queue->type || - v4l2_buf->memory != V4L2_MEMORY_MMAP) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer type (%u) " - "and/or memory (%u).\n", v4l2_buf->type, - v4l2_buf->memory); - return -EINVAL; - } + int ret; mutex_lock(&queue->mutex); - if (v4l2_buf->index >= queue->count) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Out of range index.\n"); - ret = -EINVAL; - goto done; - } - - buf = &queue->buffer[v4l2_buf->index]; - if (buf->state != UVC_BUF_STATE_IDLE) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer state " - "(%u).\n", buf->state); - ret = -EINVAL; - goto done; - } - - if (v4l2_buf->type == V4L2_BUF_TYPE_VIDEO_OUTPUT && - v4l2_buf->bytesused > buf->buf.length) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Bytes used out of bounds.\n"); - ret = -EINVAL; - goto done; - } - - spin_lock_irqsave(&queue->irqlock, flags); - if (queue->flags & UVC_QUEUE_DISCONNECTED) { - spin_unlock_irqrestore(&queue->irqlock, flags); - ret = -ENODEV; - goto done; - } - buf->state = UVC_BUF_STATE_QUEUED; - if (v4l2_buf->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) - buf->buf.bytesused = 0; - else - buf->buf.bytesused = v4l2_buf->bytesused; - - list_add_tail(&buf->stream, &queue->mainqueue); - list_add_tail(&buf->queue, &queue->irqqueue); - spin_unlock_irqrestore(&queue->irqlock, flags); - -done: + ret = vb2_qbuf(&queue->queue, buf); mutex_unlock(&queue->mutex); - return ret; -} -static int uvc_queue_waiton(struct uvc_buffer *buf, int nonblocking) -{ - if (nonblocking) { - return (buf->state != UVC_BUF_STATE_QUEUED && - buf->state != UVC_BUF_STATE_ACTIVE && - buf->state != UVC_BUF_STATE_READY) - ? 0 : -EAGAIN; - } - - return wait_event_interruptible(buf->wait, - buf->state != UVC_BUF_STATE_QUEUED && - buf->state != UVC_BUF_STATE_ACTIVE && - buf->state != UVC_BUF_STATE_READY); + return ret; } -/* - * Dequeue a video buffer. If nonblocking is false, block until a buffer is - * available. - */ -int uvc_dequeue_buffer(struct uvc_video_queue *queue, - struct v4l2_buffer *v4l2_buf, int nonblocking) +int uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf, + int nonblocking) { - struct uvc_buffer *buf; - int ret = 0; - - if (v4l2_buf->type != queue->type || - v4l2_buf->memory != V4L2_MEMORY_MMAP) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer type (%u) " - "and/or memory (%u).\n", v4l2_buf->type, - v4l2_buf->memory); - return -EINVAL; - } + int ret; mutex_lock(&queue->mutex); - if (list_empty(&queue->mainqueue)) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Empty buffer queue.\n"); - ret = -EINVAL; - goto done; - } - - buf = list_first_entry(&queue->mainqueue, struct uvc_buffer, stream); - if ((ret = uvc_queue_waiton(buf, nonblocking)) < 0) - goto done; - - uvc_trace(UVC_TRACE_CAPTURE, "Dequeuing buffer %u (%u, %u bytes).\n", - buf->buf.index, buf->state, buf->buf.bytesused); - - switch (buf->state) { - case UVC_BUF_STATE_ERROR: - uvc_trace(UVC_TRACE_CAPTURE, "[W] Corrupted data " - "(transmission error).\n"); - ret = -EIO; - case UVC_BUF_STATE_DONE: - buf->state = UVC_BUF_STATE_IDLE; - break; - - case UVC_BUF_STATE_IDLE: - case UVC_BUF_STATE_QUEUED: - case UVC_BUF_STATE_ACTIVE: - case UVC_BUF_STATE_READY: - default: - uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer state %u " - "(driver bug?).\n", buf->state); - ret = -EINVAL; - goto done; - } - - list_del(&buf->stream); - __uvc_query_buffer(buf, v4l2_buf); - -done: + ret = vb2_dqbuf(&queue->queue, buf, nonblocking); mutex_unlock(&queue->mutex); - return ret; -} -/* - * VMA operations. - */ -static void uvc_vm_open(struct vm_area_struct *vma) -{ - struct uvc_buffer *buffer = vma->vm_private_data; - buffer->vma_use_count++; -} - -static void uvc_vm_close(struct vm_area_struct *vma) -{ - struct uvc_buffer *buffer = vma->vm_private_data; - buffer->vma_use_count--; + return ret; } -static const struct vm_operations_struct uvc_vm_ops = { - .open = uvc_vm_open, - .close = uvc_vm_close, -}; - -/* - * Memory-map a video buffer. - * - * This function implements video buffers memory mapping and is intended to be - * used by the device mmap handler. - */ int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma) { - struct uvc_buffer *uninitialized_var(buffer); - struct page *page; - unsigned long addr, start, size; - unsigned int i; - int ret = 0; - - start = vma->vm_start; - size = vma->vm_end - vma->vm_start; + int ret; mutex_lock(&queue->mutex); + ret = vb2_mmap(&queue->queue, vma); + mutex_unlock(&queue->mutex); - for (i = 0; i < queue->count; ++i) { - buffer = &queue->buffer[i]; - if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff) - break; - } - - if (i == queue->count || PAGE_ALIGN(size) != queue->buf_size) { - ret = -EINVAL; - goto done; - } - - /* - * VM_IO marks the area as being an mmaped region for I/O to a - * device. It also prevents the region from being core dumped. - */ - vma->vm_flags |= VM_IO; - - addr = (unsigned long)queue->mem + buffer->buf.m.offset; -#ifdef CONFIG_MMU - while (size > 0) { - page = vmalloc_to_page((void *)addr); - if ((ret = vm_insert_page(vma, start, page)) < 0) - goto done; - - start += PAGE_SIZE; - addr += PAGE_SIZE; - size -= PAGE_SIZE; - } -#endif + return ret; +} - vma->vm_ops = &uvc_vm_ops; - vma->vm_private_data = buffer; - uvc_vm_open(vma); +unsigned int uvc_queue_poll(struct uvc_video_queue *queue, struct file *file, + poll_table *wait) +{ + unsigned int ret; -done: + mutex_lock(&queue->mutex); + ret = vb2_poll(&queue->queue, file, wait); mutex_unlock(&queue->mutex); + return ret; } -/* - * Poll the video queue. +/* ----------------------------------------------------------------------------- * - * This function implements video queue polling and is intended to be used by - * the device poll handler. */ -unsigned int uvc_queue_poll(struct uvc_video_queue *queue, struct file *file, - poll_table *wait) + +/* + * Check if buffers have been allocated. + */ +int uvc_queue_allocated(struct uvc_video_queue *queue) { - struct uvc_buffer *buf; - unsigned int mask = 0; + int allocated; mutex_lock(&queue->mutex); - if (list_empty(&queue->mainqueue)) { - mask |= POLLERR; - goto done; - } - buf = list_first_entry(&queue->mainqueue, struct uvc_buffer, stream); - - poll_wait(file, &buf->wait, wait); - if (buf->state == UVC_BUF_STATE_DONE || - buf->state == UVC_BUF_STATE_ERROR) { - if (queue->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) - mask |= POLLIN | POLLRDNORM; - else - mask |= POLLOUT | POLLWRNORM; - } - -done: + allocated = vb2_is_busy(&queue->queue); mutex_unlock(&queue->mutex); - return mask; + + return allocated; } #ifndef CONFIG_MMU @@ -515,7 +260,7 @@ unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue, ret = -EINVAL; goto done; } - ret = (unsigned long)queue->mem + buffer->buf.m.offset; + ret = (unsigned long)buf->mem; done: mutex_unlock(&queue->mutex); return ret; @@ -540,27 +285,24 @@ done: */ int uvc_queue_enable(struct uvc_video_queue *queue, int enable) { - unsigned int i; - int ret = 0; + unsigned long flags; + int ret; mutex_lock(&queue->mutex); if (enable) { - if (uvc_queue_streaming(queue)) { - ret = -EBUSY; + ret = vb2_streamon(&queue->queue, queue->queue.type); + if (ret < 0) goto done; - } - queue->flags |= UVC_QUEUE_STREAMING; + queue->buf_used = 0; } else { - uvc_queue_cancel(queue, 0); - INIT_LIST_HEAD(&queue->mainqueue); - - for (i = 0; i < queue->count; ++i) { - queue->buffer[i].error = 0; - queue->buffer[i].state = UVC_BUF_STATE_IDLE; - } + ret = vb2_streamoff(&queue->queue, queue->queue.type); + if (ret < 0) + goto done; - queue->flags &= ~UVC_QUEUE_STREAMING; + spin_lock_irqsave(&queue->irqlock, flags); + INIT_LIST_HEAD(&queue->irqqueue); + spin_unlock_irqrestore(&queue->irqlock, flags); } done: @@ -591,12 +333,12 @@ void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect) queue); list_del(&buf->queue); buf->state = UVC_BUF_STATE_ERROR; - wake_up(&buf->wait); + vb2_buffer_done(&buf->buf, VB2_BUF_STATE_ERROR); } /* This must be protected by the irqlock spinlock to avoid race - * conditions between uvc_queue_buffer and the disconnection event that + * conditions between uvc_buffer_queue and the disconnection event that * could result in an interruptible wait in uvc_dequeue_buffer. Do not - * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED + * blindly replace this logic by checking for the UVC_QUEUE_DISCONNECTED * state outside the queue code. */ if (disconnect) @@ -613,14 +355,12 @@ struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue, if ((queue->flags & UVC_QUEUE_DROP_CORRUPTED) && buf->error) { buf->error = 0; buf->state = UVC_BUF_STATE_QUEUED; - buf->buf.bytesused = 0; + vb2_set_plane_payload(&buf->buf, 0, 0); return buf; } spin_lock_irqsave(&queue->irqlock, flags); list_del(&buf->queue); - buf->error = 0; - buf->state = UVC_BUF_STATE_DONE; if (!list_empty(&queue->irqqueue)) nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer, queue); @@ -628,7 +368,9 @@ struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue, nextbuf = NULL; spin_unlock_irqrestore(&queue->irqlock, flags); - wake_up(&buf->wait); + buf->state = buf->error ? VB2_BUF_STATE_ERROR : UVC_BUF_STATE_DONE; + vb2_set_plane_payload(&buf->buf, 0, buf->bytesused); + vb2_buffer_done(&buf->buf, VB2_BUF_STATE_DONE); + return nextbuf; } - |