From b6098c30423cb1f0f5a4d0a5495e2670e274e544 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Thu, 4 Dec 2014 18:49:58 +0200 Subject: [PATCH] virtio: add API to detect legacy devices transports need to be able to detect legacy-only devices (ATM balloon only) to use legacy path to drive them. Add a core API to do just that. The implementation just blacklists balloon: not too pretty, but let's not over-engineer. Signed-off-by: Michael S. Tsirkin Acked-by: Cornelia Huck --- drivers/virtio/virtio.c | 7 +++++++ include/linux/virtio.h | 2 ++ 2 files changed, 9 insertions(+) diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index fa6b75db5f1f..224f85442f3f 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -3,6 +3,7 @@ #include #include #include +#include /* Unique numbering for virtio devices. */ static DEFINE_IDA(virtio_index_ida); @@ -267,6 +268,12 @@ static struct bus_type virtio_bus = { .remove = virtio_dev_remove, }; +bool virtio_device_is_legacy_only(struct virtio_device_id id) +{ + return id.device == VIRTIO_ID_BALLOON; +} +EXPORT_SYMBOL_GPL(virtio_device_is_legacy_only); + int register_virtio_driver(struct virtio_driver *driver) { /* Catch this early. */ diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 2bbf62697671..d666bcb57401 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -108,6 +108,8 @@ struct virtio_device { void *priv; }; +bool virtio_device_is_legacy_only(struct virtio_device_id id); + static inline struct virtio_device *dev_to_virtio(struct device *_dev) { return container_of(_dev, struct virtio_device, dev); -- 2.20.1