This patch adds 2 helpers functions to add and remove vb2 buffers from a queue. With these 2 and vb2_get_buffer(), bufs field of struct vb2_queue becomes like a private member of the structure. After each call to vb2_get_buffer() we need to be sure that we get a valid pointer so check the return value of all of them. Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx> --- .../media/common/videobuf2/videobuf2-core.c | 151 +++++++++++++----- .../media/common/videobuf2/videobuf2-v4l2.c | 51 ++++-- 2 files changed, 146 insertions(+), 56 deletions(-) diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c index b00e68fd747f..17b0dafacaab 100644 --- a/drivers/media/common/videobuf2/videobuf2-core.c +++ b/drivers/media/common/videobuf2/videobuf2-core.c @@ -407,6 +407,31 @@ static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb) vb->skip_cache_sync_on_finish = 1; } +/** + * vb2_queue_add_buffer() - add a buffer to a queue + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @vb: pointer to &struct vb2_buffer to be added to the queue. + * @index: index where add vb2_buffer in the queue + */ +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]); + + q->bufs[index] = vb; + vb->index = index; + vb->vb2_queue = q; +} + +/** + * vb2_queue_remove_buffer() - remove a buffer from a queue + * @vb: pointer to &struct vb2_buffer to be removed from the queue. + */ +static void vb2_queue_remove_buffer(struct vb2_buffer *vb) +{ + vb->vb2_queue->bufs[vb->index] = NULL; + vb->vb2_queue = NULL; +} + /* * __vb2_queue_alloc() - allocate vb2 buffer structures and (for MMAP type) * video buffer memory for all buffers/planes on the queue and initializes the @@ -435,9 +460,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, } vb->state = VB2_BUF_STATE_DEQUEUED; - vb->vb2_queue = q; vb->num_planes = num_planes; - vb->index = q->num_buffers + buffer; vb->type = q->type; vb->memory = memory; init_buffer_cache_hints(q, vb); @@ -445,9 +468,9 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, vb->planes[plane].length = plane_sizes[plane]; vb->planes[plane].min_length = plane_sizes[plane]; } - call_void_bufop(q, init_buffer, vb); - q->bufs[vb->index] = vb; + vb2_queue_add_buffer(q, vb, q->num_buffers + buffer); + call_void_bufop(q, init_buffer, vb); /* Allocate video buffer memory for the MMAP type */ if (memory == VB2_MEMORY_MMAP) { @@ -455,7 +478,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, if (ret) { dprintk(q, 1, "failed allocating memory for buffer %d\n", buffer); - q->bufs[vb->index] = NULL; + vb2_queue_remove_buffer(vb); kfree(vb); break; } @@ -470,7 +493,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, dprintk(q, 1, "buffer %d %p initialization failed\n", buffer, vb); __vb2_buf_mem_free(vb); - q->bufs[vb->index] = NULL; + vb2_queue_remove_buffer(vb); kfree(vb); break; } @@ -493,7 +516,7 @@ static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers) for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; ++buffer) { - vb = q->bufs[buffer]; + vb = vb2_get_buffer(q, buffer); if (!vb) continue; @@ -521,7 +544,7 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers) /* Call driver-provided cleanup function for each buffer, if provided */ for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; ++buffer) { - struct vb2_buffer *vb = q->bufs[buffer]; + struct vb2_buffer *vb = vb2_get_buffer(q, buffer); if (vb && vb->planes[0].mem_priv) call_void_vb_qop(vb, buf_cleanup, vb); @@ -562,15 +585,20 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers) q->cnt_unprepare_streaming = 0; } for (buffer = 0; buffer < q->num_buffers; ++buffer) { - struct vb2_buffer *vb = q->bufs[buffer]; - bool unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put || - vb->cnt_mem_prepare != vb->cnt_mem_finish || - vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr || - vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf || - vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf || - vb->cnt_buf_queue != vb->cnt_buf_done || - vb->cnt_buf_prepare != vb->cnt_buf_finish || - vb->cnt_buf_init != vb->cnt_buf_cleanup; + struct vb2_buffer *vb = vb2_get_buffer(q, buffer); + bool unbalanced; + + if (!vb) + continue; + + unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put || + vb->cnt_mem_prepare != vb->cnt_mem_finish || + vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr || + vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf || + vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf || + vb->cnt_buf_queue != vb->cnt_buf_done || + vb->cnt_buf_prepare != vb->cnt_buf_finish || + vb->cnt_buf_init != vb->cnt_buf_cleanup; if (unbalanced) { pr_info("unbalanced counters for queue %p, buffer %d:\n", @@ -610,8 +638,13 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers) /* Free vb2 buffers */ for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; ++buffer) { - kfree(q->bufs[buffer]); - q->bufs[buffer] = NULL; + struct vb2_buffer *vb = vb2_get_buffer(q, buffer); + + if (!vb) + continue; + + vb2_queue_remove_buffer(vb); + kfree(vb); } q->num_buffers -= buffers; @@ -647,7 +680,12 @@ static bool __buffers_in_use(struct vb2_queue *q) { unsigned int buffer; for (buffer = 0; buffer < q->num_buffers; ++buffer) { - if (vb2_buffer_in_use(q, q->bufs[buffer])) + struct vb2_buffer *vb = vb2_get_buffer(q, buffer); + + if (!vb) + continue; + + if (vb2_buffer_in_use(q, vb)) return true; } return false; @@ -1632,7 +1670,11 @@ static int vb2_start_streaming(struct vb2_queue *q) * correctly return them to vb2. */ for (i = 0; i < q->num_buffers; ++i) { - vb = q->bufs[i]; + vb = vb2_get_buffer(q, i); + + if (!vb) + continue; + if (vb->state == VB2_BUF_STATE_ACTIVE) vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED); } @@ -2033,12 +2075,18 @@ static void __vb2_queue_cancel(struct vb2_queue *q) * to vb2 in stop_streaming(). */ if (WARN_ON(atomic_read(&q->owned_by_drv_count))) { - for (i = 0; i < q->num_buffers; ++i) - if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE) { - pr_warn("driver bug: stop_streaming operation is leaving buf %p in active state\n", - q->bufs[i]); - vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR); + for (i = 0; i < q->num_buffers; ++i) { + struct vb2_buffer *vb = vb2_get_buffer(q, i); + + if (!vb) + continue; + + if (vb->state == VB2_BUF_STATE_ACTIVE) { + pr_warn("driver bug: stop_streaming operation is leaving buffer %u in active state\n", + vb->index); + vb2_buffer_done(vb, VB2_BUF_STATE_ERROR); } + } /* Must be zero now */ WARN_ON(atomic_read(&q->owned_by_drv_count)); } @@ -2072,9 +2120,14 @@ static void __vb2_queue_cancel(struct vb2_queue *q) * be changed, so we can't move the buf_finish() to __vb2_dqbuf(). */ for (i = 0; i < q->num_buffers; ++i) { - struct vb2_buffer *vb = q->bufs[i]; - struct media_request *req = vb->req_obj.req; + struct vb2_buffer *vb; + struct media_request *req; + vb = vb2_get_buffer(q, i); + if (!vb) + continue; + + req = vb->req_obj.req; /* * If a request is associated with this buffer, then * call buf_request_cancel() to give the driver to complete() @@ -2223,10 +2276,12 @@ static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off, buffer = (off >> PLANE_INDEX_SHIFT) & BUFFER_INDEX_MASK; *plane = (off >> PAGE_SHIFT) & PLANE_INDEX_MASK; - if (buffer >= q->num_buffers || *plane >= q->bufs[buffer]->num_planes) + *vb = vb2_get_buffer(q, buffer); + if (!*vb) + return -EINVAL; + if (*plane >= (*vb)->num_planes) return -EINVAL; - *vb = q->bufs[buffer]; return 0; } @@ -2614,6 +2669,7 @@ struct vb2_fileio_data { static int __vb2_init_fileio(struct vb2_queue *q, int read) { struct vb2_fileio_data *fileio; + struct vb2_buffer *vb; int i, ret; unsigned int count = 0; @@ -2664,11 +2720,18 @@ static int __vb2_init_fileio(struct vb2_queue *q, int read) if (ret) goto err_kfree; + /* + * Userspace can never add or delete buffers later, so there + * will never be holes. It is safe to assume that vb2_get_buffer(q, 0) + * will always return a valid vb pointer + */ + vb = vb2_get_buffer(q, 0); + /* * Check if plane_count is correct * (multiplane buffers are not supported). */ - if (q->bufs[0]->num_planes != 1) { + if (vb->num_planes != 1) { ret = -EBUSY; goto err_reqbufs; } @@ -2677,12 +2740,15 @@ static int __vb2_init_fileio(struct vb2_queue *q, int read) * Get kernel address of each buffer. */ for (i = 0; i < q->num_buffers; i++) { - fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0); + vb = vb2_get_buffer(q, i); + WARN_ON_ONCE(!vb); + + fileio->bufs[i].vaddr = vb2_plane_vaddr(vb, 0); if (fileio->bufs[i].vaddr == NULL) { ret = -EINVAL; goto err_reqbufs; } - fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0); + fileio->bufs[i].size = vb2_plane_size(vb, 0); } /* @@ -2810,15 +2876,17 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_ fileio->cur_index = index; buf = &fileio->bufs[index]; - b = q->bufs[index]; + + /* b can never be NULL when using fileio. */ + b = vb2_get_buffer(q, index); /* * Get number of bytes filled by the driver */ buf->pos = 0; buf->queued = 0; - buf->size = read ? vb2_get_plane_payload(q->bufs[index], 0) - : vb2_plane_size(q->bufs[index], 0); + buf->size = read ? vb2_get_plane_payload(b, 0) + : vb2_plane_size(b, 0); /* Compensate for data_offset on read in the multiplanar case. */ if (is_multiplanar && read && b->planes[0].data_offset < buf->size) { @@ -2861,7 +2929,8 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_ * Queue next buffer if required. */ if (buf->pos == buf->size || (!read && fileio->write_immediately)) { - struct vb2_buffer *b = q->bufs[index]; + /* b can never be NULL when using fileio. */ + struct vb2_buffer *b = vb2_get_buffer(q, index); /* * Check if this is the last buffer to read. @@ -2888,7 +2957,7 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_ */ buf->pos = 0; buf->queued = 1; - buf->size = vb2_plane_size(q->bufs[index], 0); + buf->size = vb2_plane_size(b, 0); fileio->q_count += 1; /* * If we are queuing up buffers for the first time, then @@ -2959,7 +3028,9 @@ static int vb2_thread(void *data) * Call vb2_dqbuf to get buffer back. */ if (prequeue) { - vb = q->bufs[index++]; + vb = vb2_get_buffer(q, index++); + if (!vb) + continue; prequeue--; } else { call_void_qop(q, wait_finish, q); @@ -2968,7 +3039,7 @@ static int vb2_thread(void *data) call_void_qop(q, wait_prepare, q); dprintk(q, 5, "file io: vb2_dqbuf result: %d\n", ret); if (!ret) - vb = q->bufs[index]; + vb = vb2_get_buffer(q, index); } if (ret || threadio->stop) break; diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c index 697c8a9f98cd..3395e702ad1f 100644 --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -383,9 +383,9 @@ static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md return -EINVAL; } - if (q->bufs[b->index] == NULL) { - /* Should never happen */ - dprintk(q, 1, "%s: buffer is NULL\n", opname); + vb = vb2_get_buffer(q, b->index); + if (!vb) { + dprintk(q, 1, "%s: buffer %u is NULL\n", opname, b->index); return -EINVAL; } @@ -394,7 +394,6 @@ static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md return -EINVAL; } - vb = q->bufs[b->index]; vbuf = to_vb2_v4l2_buffer(vb); ret = __verify_planes_array(vb, b); if (ret) @@ -628,11 +627,22 @@ static const struct vb2_buf_ops v4l2_buf_ops = { struct vb2_buffer *vb2_find_buffer(struct vb2_queue *q, u64 timestamp) { unsigned int i; + struct vb2_buffer *vb2; - for (i = 0; i < q->num_buffers; i++) - if (q->bufs[i]->copied_timestamp && - q->bufs[i]->timestamp == timestamp) - return vb2_get_buffer(q, i); + /* + * 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 < q->num_buffers; i++) { + vb2 = vb2_get_buffer(q, i); + + if (!vb2) + continue; + + if (vb2->copied_timestamp && + vb2->timestamp == timestamp) + return vb2; + } return NULL; } EXPORT_SYMBOL_GPL(vb2_find_buffer); @@ -660,11 +670,12 @@ int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b) return -EINVAL; } - if (b->index >= q->num_buffers) { - dprintk(q, 1, "buffer index out of range\n"); + vb = vb2_get_buffer(q, b->index); + if (!vb) { + dprintk(q, 1, "can't find the requested buffer %u\n", b->index); return -EINVAL; } - vb = q->bufs[b->index]; + ret = __verify_planes_array(vb, b); if (!ret) vb2_core_querybuf(q, vb, b); @@ -734,11 +745,11 @@ int vb2_prepare_buf(struct vb2_queue *q, struct media_device *mdev, if (b->flags & V4L2_BUF_FLAG_REQUEST_FD) return -EINVAL; - if (b->index >= q->num_buffers) { - dprintk(q, 1, "buffer index out of range\n"); + vb = vb2_get_buffer(q, b->index); + if (!vb) { + dprintk(q, 1, "can't find the requested buffer %u\n", b->index); return -EINVAL; } - vb = q->bufs[b->index]; ret = vb2_queue_or_prepare_buf(q, mdev, b, true, NULL); @@ -822,7 +833,11 @@ int vb2_qbuf(struct vb2_queue *q, struct media_device *mdev, dprintk(q, 1, "buffer index out of range\n"); return -EINVAL; } - vb = q->bufs[b->index]; + vb = vb2_get_buffer(q, b->index); + if (!vb) { + dprintk(q, 1, "can't find the requested buffer %u\n", b->index); + return -EINVAL; + } ret = vb2_queue_or_prepare_buf(q, mdev, b, false, &req); if (ret) @@ -893,7 +908,11 @@ int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb) dprintk(q, 1, "buffer index out of range\n"); return -EINVAL; } - vb = q->bufs[eb->index]; + vb = vb2_get_buffer(q, eb->index); + if (!vb) { + dprintk(q, 1, "can't find the requested buffer %u\n", eb->index); + return -EINVAL; + } return vb2_core_expbuf(q, &eb->fd, eb->type, vb, eb->plane, eb->flags); -- 2.39.2