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Therefore the number of entries has been limited to 8. Support larger frame descriptors by making the entry field a pointer that by default points to a pre-allocated array while the get_frame_desc() pad o may allocate as much memory as required, up to V4L2_FRAME_DESC_ENTRY_MAX which is changed to 64. The caller is also responsible for releasing the allocated memory by calling v4l2_subdev_free_frame_desc(). Signed-off-by: Sakari Ailus Reviewed-by: Frank Li --- drivers/media/v4l2-core/v4l2-subdev.c | 45 ++++++++++++++++++++------- include/media/v4l2-subdev.h | 42 ++++++++++++++++++------- 2 files changed, 63 insertions(+), 24 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index a5c53dc8c396..e15d3f63e004 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -63,10 +63,6 @@ static bool v4l2_subdev_enable_streams_api; /* * Maximum stream ID is 63 for now, as we use u64 bitmask to represent a set * of streams. - * - * Note that V4L2_FRAME_DESC_ENTRY_MAX is related: V4L2_FRAME_DESC_ENTRY_MAX - * restricts the total number of streams in a pad, although the stream ID is - * not restricted. */ #define V4L2_SUBDEV_MAX_STREAM_ID 63 @@ -354,6 +350,7 @@ static int call_set_frame_interval(struct v4l2_subdev *sd, static int call_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad, struct v4l2_mbus_frame_desc *fd) { + unsigned int type; unsigned int i; int ret; @@ -362,16 +359,26 @@ static int call_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad, return -EOPNOTSUPP; #endif - memset(fd, 0, sizeof(*fd)); + type = fd->type; + memset_after(fd, 0, type); + fd->entry = fd->entry_mem; + fd->len_entries = ARRAY_SIZE(fd->entry_mem); ret = sd->ops->pad->get_frame_desc(sd, pad, fd); if (ret) return ret; + if (type == V4L2_MBUS_FRAME_DESC_TYPE_UNDEFINED) { + type = fd->type; + } else if (type != fd->type) { + dev_dbg(sd->dev, "Expected frame descriptor type %u, got %u\n", + type, fd->type); + return -EINVAL; + } + dev_dbg(sd->dev, "Frame descriptor on pad %u, type %s\n", pad, - fd->type == V4L2_MBUS_FRAME_DESC_TYPE_PARALLEL ? "parallel" : - fd->type == V4L2_MBUS_FRAME_DESC_TYPE_CSI2 ? "CSI-2" : - "unknown"); + type == V4L2_MBUS_FRAME_DESC_TYPE_PARALLEL ? "parallel" : + type == V4L2_MBUS_FRAME_DESC_TYPE_CSI2 ? "CSI-2" : "unknown"); for (i = 0; i < fd->num_entries; i++) { struct v4l2_mbus_frame_desc_entry *entry = &fd->entry[i]; @@ -1086,9 +1093,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg, * descriptor accordingly, with up to one entry per route. Until * the frame descriptors entries get allocated dynamically, * limit the number of active routes to - * V4L2_FRAME_DESC_ENTRY_MAX. + * V4L2_FRAME_DESC_ENTRY_PREALLOC. */ - if (num_active_routes > V4L2_FRAME_DESC_ENTRY_MAX) + if (num_active_routes > V4L2_FRAME_DESC_ENTRY_PREALLOC) return -E2BIG; /* @@ -2638,7 +2645,7 @@ int __v4l2_subdev_get_frame_desc_passthrough(struct v4l2_subdev *sd, return -EPIPE; } - if (fd->num_entries >= V4L2_FRAME_DESC_ENTRY_MAX) { + if (fd->num_entries >= V4L2_FRAME_DESC_ENTRY_PREALLOC) { dev_dbg(dev, "Frame desc entry limit reached\n"); return -E2BIG; } @@ -2703,6 +2710,14 @@ v4l2_subdev_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad, goto err_free; } + if (desc->num_entries > desc->len_entries) { + dev_dbg(sd->dev, + "too many frame descriptors; got %u, expected at most %u\n", + desc->num_entries, desc->len_entries); + ret = -EINVAL; + goto err_free; + } + return desc; } @@ -2717,7 +2732,10 @@ v4l2_subdev_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad, if (ret < 0) goto err_free; - struct v4l2_mbus_frame_desc_entry *entry = &desc->entry[0]; + desc->entry = desc->entry_mem; + desc->len_entries = ARRAY_SIZE(desc->entry_mem); + + struct v4l2_mbus_frame_desc_entry *entry = desc->entry; entry->pixelcode = subdev_fmt.format.code; @@ -2742,6 +2760,9 @@ EXPORT_SYMBOL_GPL(v4l2_subdev_get_frame_desc); void v4l2_subdev_free_frame_desc(struct v4l2_mbus_frame_desc *desc) { + if (desc->entry != desc->entry_mem) + kfree(desc->entry); + kfree(desc); } EXPORT_SYMBOL_GPL(v4l2_subdev_free_frame_desc); diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index c10ca3f5d979..daebf8982c43 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -366,11 +366,13 @@ struct v4l2_mbus_frame_desc_entry { } bus; }; - /* - * If this number is too small, it should be dropped altogether and the - * API switched to a dynamic number of frame descriptor entries. - */ -#define V4L2_FRAME_DESC_ENTRY_MAX 8 +/* Size of the statically allocated frame descriptor array. */ +#define V4L2_FRAME_DESC_ENTRY_PREALLOC 8 +/* + * Maximum number of dynamically allocated frame descriptors. Note that + * V4L2_SUBDEV_MAX_STREAM_ID is related to this limit as well. + */ +#define V4L2_FRAME_DESC_ENTRY_MAX 64 /** * enum v4l2_mbus_frame_desc_type - media bus frame description type @@ -393,13 +395,17 @@ enum v4l2_mbus_frame_desc_type { /** * struct v4l2_mbus_frame_desc - media bus data frame description * @type: type of the bus (enum v4l2_mbus_frame_desc_type) - * @entry: frame descriptors array - * @num_entries: number of entries in @entry array + * @entry_mem: memory for the frame descriptors (@entry) + * @entry: pointer to the frame descriptors + * @num_entries: number of entries in @entry + * @len_entries: number of entries allocated for @entry */ struct v4l2_mbus_frame_desc { enum v4l2_mbus_frame_desc_type type; - struct v4l2_mbus_frame_desc_entry entry[V4L2_FRAME_DESC_ENTRY_MAX]; + struct v4l2_mbus_frame_desc_entry entry_mem[V4L2_FRAME_DESC_ENTRY_PREALLOC]; + struct v4l2_mbus_frame_desc_entry *entry; unsigned short num_entries; + unsigned short len_entries; }; /** @@ -781,7 +787,17 @@ struct v4l2_subdev_state { * @link_validate: used by the media controller code to check if the links * that belongs to a pipeline can be used for stream. * - * @get_frame_desc: get the current low level media bus frame parameters. + * @get_frame_desc: get the current low level media bus frame parameters. The + * callback is required to update the num_entries field to the + * total number of entries in the frame descriptor. The + * callback shall fill the first entries array up to + * len_entries, which signifies the number of entries + * allocated. If the number of entries needed exceeds + * len_entries, allocate enough memory using kzalloc_objs() or + * a similar function returning kmalloc() memory. Never call + * this directly in drivers, use v4l2_subdev_get_frame_desc() + * instead. The maximum number of num_entries is + * V4L2_FRAME_DESC_ENTRY_MAX. * * @set_frame_desc: set the low level media bus frame parameters, @fd array * may be adjusted by the subdev driver to device capabilities. @@ -1794,8 +1810,9 @@ int v4l2_subdev_get_frame_desc_passthrough(struct v4l2_subdev *sd, * * The caller is required to set @desc->type to the expected bus type. * - * The caller is required to release the memory of the frame descriptor entries - * for each frame descriptor obtained by calling this function using + * The entries in the frame descriptor are allocated based on the need. The + * caller is required to release the memory of the frame descriptor entries for + * each frame descriptor obtained by calling this function using * v4l2_subdev_free_frame_desc(). * * Use __free() to release the frame descriptor automatically:: @@ -1813,7 +1830,8 @@ v4l2_subdev_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad, * v4l2_subdev_free_frame_desc() - Release the memory of a frame descriptor * @desc: A pointer to a frame descriptor * - * Release the frame descriptor. + * Release the frame descriptor entries in a frame descriptor as well as the + * frame descriptor itself. */ void v4l2_subdev_free_frame_desc(struct v4l2_mbus_frame_desc *desc); -- 2.47.3