From c838530d230bc638d79b78737fc4488ffc28c1ee Mon Sep 17 00:00:00 2001 From: Benjamin Gaignard Date: Thu, 9 Nov 2023 17:34:59 +0100 Subject: media: media videobuf2: Be more flexible on the number of queue stored buffers Add 'max_num_buffers' field in vb2_queue struct to let drivers decide how many buffers could be stored in a queue. This require 'bufs' array to be allocated at queue init time and freed when releasing the queue. By default VB2_MAX_FRAME remains the limit. Signed-off-by: Benjamin Gaignard Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/common/videobuf2/videobuf2-core.c | 46 ++++++++++++++++++++----- drivers/media/common/videobuf2/videobuf2-v4l2.c | 6 ++-- include/media/videobuf2-core.h | 12 ++++++- 3 files changed, 52 insertions(+), 12 deletions(-) diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c index ce5b84b9bcd4..8c1df829745b 100644 --- a/drivers/media/common/videobuf2/videobuf2-core.c +++ b/drivers/media/common/videobuf2/videobuf2-core.c @@ -421,7 +421,7 @@ static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb) */ static void vb2_queue_add_buffer(struct vb2_queue *q, struct vb2_buffer *vb, unsigned int index) { - WARN_ON(index >= VB2_MAX_FRAME || q->bufs[index] || vb->vb2_queue); + WARN_ON(index >= q->max_num_buffers || q->bufs[index] || vb->vb2_queue); q->bufs[index] = vb; vb->index = index; @@ -454,9 +454,12 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, struct vb2_buffer *vb; int ret; - /* Ensure that q->num_buffers+num_buffers is below VB2_MAX_FRAME */ + /* + * Ensure that the number of already queue + the number of buffers already + * in the queue is below q->max_num_buffers + */ num_buffers = min_t(unsigned int, num_buffers, - VB2_MAX_FRAME - q_num_buffers); + q->max_num_buffers - q_num_buffers); for (buffer = 0; buffer < num_buffers; ++buffer) { /* Allocate vb2 buffer structures */ @@ -818,7 +821,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, unsigned plane_sizes[VB2_MAX_PLANES] = { }; bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT; unsigned int i; - int ret; + int ret = 0; if (q->streaming) { dprintk(q, 1, "streaming active\n"); @@ -862,17 +865,22 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, /* * Make sure the requested values and current defaults are sane. */ - WARN_ON(q->min_buffers_needed > VB2_MAX_FRAME); num_buffers = max_t(unsigned int, *count, q->min_buffers_needed); - num_buffers = min_t(unsigned int, num_buffers, VB2_MAX_FRAME); + num_buffers = min_t(unsigned int, num_buffers, q->max_num_buffers); memset(q->alloc_devs, 0, sizeof(q->alloc_devs)); /* * Set this now to ensure that drivers see the correct q->memory value * in the queue_setup op. */ mutex_lock(&q->mmap_lock); + if (!q->bufs) + q->bufs = kcalloc(q->max_num_buffers, sizeof(*q->bufs), GFP_KERNEL); + if (!q->bufs) + ret = -ENOMEM; q->memory = memory; mutex_unlock(&q->mmap_lock); + if (ret) + return ret; set_queue_coherency(q, non_coherent_mem); /* @@ -981,7 +989,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, bool no_previous_buffers = !q_num_bufs; int ret = 0; - if (q_num_bufs == VB2_MAX_FRAME) { + if (q->num_buffers == q->max_num_buffers) { dprintk(q, 1, "maximum number of buffers already allocated\n"); return -ENOBUFS; } @@ -998,7 +1006,13 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, */ mutex_lock(&q->mmap_lock); q->memory = memory; + if (!q->bufs) + q->bufs = kcalloc(q->max_num_buffers, sizeof(*q->bufs), GFP_KERNEL); + if (!q->bufs) + ret = -ENOMEM; mutex_unlock(&q->mmap_lock); + if (ret) + return ret; q->waiting_for_buffers = !q->is_output; set_queue_coherency(q, non_coherent_mem); } else { @@ -1010,7 +1024,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, return -EINVAL; } - num_buffers = min(*count, VB2_MAX_FRAME - q_num_bufs); + num_buffers = min(*count, q->max_num_buffers - q_num_bufs); if (requested_planes && requested_sizes) { num_planes = requested_planes; @@ -2470,6 +2484,16 @@ int vb2_core_queue_init(struct vb2_queue *q) /* * Sanity check */ + /* + * For drivers who don't support max_num_buffers ensure + * a backward compatibility. + */ + if (!q->max_num_buffers) + q->max_num_buffers = VB2_MAX_FRAME; + + /* The maximum is limited by offset cookie encoding pattern */ + q->max_num_buffers = min_t(unsigned int, q->max_num_buffers, MAX_BUFFER_INDEX); + if (WARN_ON(!q) || WARN_ON(!q->ops) || WARN_ON(!q->mem_ops) || @@ -2479,6 +2503,10 @@ int vb2_core_queue_init(struct vb2_queue *q) WARN_ON(!q->ops->buf_queue)) return -EINVAL; + if (WARN_ON(q->max_num_buffers > MAX_BUFFER_INDEX) || + WARN_ON(q->min_buffers_needed > q->max_num_buffers)) + return -EINVAL; + if (WARN_ON(q->requires_requests && !q->supports_requests)) return -EINVAL; @@ -2525,6 +2553,8 @@ void vb2_core_queue_release(struct vb2_queue *q) __vb2_queue_cancel(q); mutex_lock(&q->mmap_lock); __vb2_queue_free(q, vb2_get_num_buffers(q)); + kfree(q->bufs); + q->bufs = NULL; mutex_unlock(&q->mmap_lock); } EXPORT_SYMBOL_GPL(vb2_core_queue_release); diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c index 9d3b828cc804..3d71c205406d 100644 --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -621,7 +621,7 @@ struct vb2_buffer *vb2_find_buffer(struct vb2_queue *q, u64 timestamp) * This loop doesn't scale if there is a really large number of buffers. * Maybe something more efficient will be needed in this case. */ - for (i = 0; i < vb2_get_num_buffers(q); i++) { + for (i = 0; i < q->max_num_buffers; i++) { vb2 = vb2_get_buffer(q, i); if (!vb2) @@ -1136,7 +1136,7 @@ int _vb2_fop_release(struct file *file, struct mutex *lock) if (lock) mutex_lock(lock); - if (file->private_data == vdev->queue->owner) { + if (!vdev->queue->owner || file->private_data == vdev->queue->owner) { vb2_queue_release(vdev->queue); vdev->queue->owner = NULL; } @@ -1264,7 +1264,7 @@ void vb2_video_unregister_device(struct video_device *vdev) */ get_device(&vdev->dev); video_unregister_device(vdev); - if (vdev->queue && vdev->queue->owner) { + if (vdev->queue) { struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index 8f9d9e4af5b1..5557d78b6f20 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -558,6 +558,9 @@ struct vb2_buf_ops { * @dma_dir: DMA mapping direction. * @bufs: videobuf2 buffer structures * @num_buffers: number of allocated/used buffers + * @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 @@ -619,8 +622,9 @@ struct vb2_queue { struct mutex mmap_lock; unsigned int memory; enum dma_data_direction dma_dir; - struct vb2_buffer *bufs[VB2_MAX_FRAME]; + struct vb2_buffer **bufs; unsigned int num_buffers; + unsigned int max_num_buffers; struct list_head queued_list; unsigned int queued_count; @@ -1248,6 +1252,12 @@ static inline void vb2_clear_last_buffer_dequeued(struct vb2_queue *q) 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 (index < q->num_buffers) return q->bufs[index]; return NULL; -- cgit