From c0acf9cfeee061f041fab778dbdcb34b6ca5e2e7 Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky Date: Thu, 9 Sep 2021 13:24:29 +0200 Subject: media: videobuf2: handle V4L2_MEMORY_FLAG_NON_COHERENT flag This patch lets user-space request a non-coherent memory allocation during CREATE_BUFS and REQBUFS ioctl calls. = CREATE_BUFS struct v4l2_create_buffers has seven 4-byte reserved areas, so reserved[0] is renamed to ->flags. The struct, thus, now has six reserved 4-byte regions. = CREATE_BUFS32 struct v4l2_create_buffers32 has seven 4-byte reserved areas, so reserved[0] is renamed to ->flags. The struct, thus, now has six reserved 4-byte regions. = REQBUFS We use one byte of a 4 byte ->reserved[1] member of struct v4l2_requestbuffers. The struct, thus, now has reserved 3 bytes. Signed-off-by: Sergey Senozhatsky Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/common/videobuf2/videobuf2-core.c | 4 ++-- drivers/media/common/videobuf2/videobuf2-v4l2.c | 31 ++++++++++++++++++++++--- 2 files changed, 30 insertions(+), 5 deletions(-) (limited to 'drivers/media/common/videobuf2') diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c index 60fb43b8f134..2266bbd239ab 100644 --- a/drivers/media/common/videobuf2/videobuf2-core.c +++ b/drivers/media/common/videobuf2/videobuf2-core.c @@ -761,7 +761,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, { unsigned int num_buffers, allocated_buffers, num_planes = 0; unsigned plane_sizes[VB2_MAX_PLANES] = { }; - bool non_coherent_mem = false; + bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT; unsigned int i; int ret; @@ -905,7 +905,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, { unsigned int num_planes = 0, num_buffers, allocated_buffers; unsigned plane_sizes[VB2_MAX_PLANES] = { }; - bool non_coherent_mem = false; + bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT; int ret; if (q->num_buffers == VB2_MAX_FRAME) { diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c index b4f70ddb09b0..6edf4508c636 100644 --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -692,12 +692,32 @@ static void fill_buf_caps(struct vb2_queue *q, u32 *caps) #endif } +static void validate_memory_flags(struct vb2_queue *q, + int memory, + u32 *flags) +{ + if (!q->allow_cache_hints || memory != V4L2_MEMORY_MMAP) { + /* + * This needs to clear V4L2_MEMORY_FLAG_NON_COHERENT only, + * but in order to avoid bugs we zero out all bits. + */ + *flags = 0; + } else { + /* Clear all unknown flags. */ + *flags &= V4L2_MEMORY_FLAG_NON_COHERENT; + } +} + int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) { int ret = vb2_verify_memory_type(q, req->memory, req->type); + u32 flags = req->flags; fill_buf_caps(q, &req->capabilities); - return ret ? ret : vb2_core_reqbufs(q, req->memory, 0, &req->count); + validate_memory_flags(q, req->memory, &flags); + req->flags = flags; + return ret ? ret : vb2_core_reqbufs(q, req->memory, + req->flags, &req->count); } EXPORT_SYMBOL_GPL(vb2_reqbufs); @@ -729,6 +749,7 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) unsigned i; fill_buf_caps(q, &create->capabilities); + validate_memory_flags(q, create->memory, &create->flags); create->index = q->num_buffers; if (create->count == 0) return ret != -EBUSY ? ret : 0; @@ -772,7 +793,7 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) if (requested_sizes[i] == 0) return -EINVAL; return ret ? ret : vb2_core_create_bufs(q, create->memory, - 0, + create->flags, &create->count, requested_planes, requested_sizes); @@ -969,13 +990,16 @@ int vb2_ioctl_reqbufs(struct file *file, void *priv, { struct video_device *vdev = video_devdata(file); int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type); + u32 flags = p->flags; fill_buf_caps(vdev->queue, &p->capabilities); + validate_memory_flags(vdev->queue, p->memory, &flags); + p->flags = flags; if (res) return res; if (vb2_queue_is_busy(vdev, file)) return -EBUSY; - res = vb2_core_reqbufs(vdev->queue, p->memory, 0, &p->count); + res = vb2_core_reqbufs(vdev->queue, p->memory, p->flags, &p->count); /* If count == 0, then the owner has released all buffers and he is no longer owner of the queue. Otherwise we have a new owner. */ if (res == 0) @@ -993,6 +1017,7 @@ int vb2_ioctl_create_bufs(struct file *file, void *priv, p->index = vdev->queue->num_buffers; fill_buf_caps(vdev->queue, &p->capabilities); + validate_memory_flags(vdev->queue, p->memory, &p->flags); /* * If count == 0, then just check if memory and type are valid. * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0. -- cgit