From 404123c2db798027e852480ed9c4accef9f1d9e6 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Wed, 29 Mar 2017 19:06:20 +0300 Subject: [PATCH] virtio: allow drivers to validate features Some drivers can't support all features in all configurations. At the moment we blindly set FEATURES_OK and later FAILED. Support this better by adding a callback drivers can use to do some early checks. Signed-off-by: Michael S. Tsirkin --- drivers/virtio/virtio.c | 6 ++++++ include/linux/virtio.h | 1 + 2 files changed, 7 insertions(+) diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index 400d70b69379..48230a5e12f2 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -232,6 +232,12 @@ static int virtio_dev_probe(struct device *_d) if (device_features & (1ULL << i)) __virtio_set_bit(dev, i); + if (drv->validate) { + err = drv->validate(dev); + if (err) + goto err; + } + err = virtio_finalize_features(dev); if (err) goto err; diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 04b0d3f95043..7edfbdb55a99 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -167,6 +167,7 @@ struct virtio_driver { unsigned int feature_table_size; const unsigned int *feature_table_legacy; unsigned int feature_table_size_legacy; + int (*validate)(struct virtio_device *dev); int (*probe)(struct virtio_device *dev); void (*scan)(struct virtio_device *dev); void (*remove)(struct virtio_device *dev); -- 2.30.2