From a61280ddddaa45f95b60dd54c05f8e0e5b6810b7 Mon Sep 17 00:00:00 2001 From: Longpeng Date: Tue, 15 Mar 2022 11:25:51 +0800 Subject: vdpa: support exposing the config size to userspace - GET_CONFIG_SIZE: return the size of the virtio config space. The size contains the fields which are conditional on feature bits. Acked-by: Jason Wang Signed-off-by: Longpeng Link: https://lore.kernel.org/r/20220315032553.455-2-longpeng2@huawei.com Signed-off-by: Michael S. Tsirkin Reviewed-by: Stefano Garzarella --- drivers/vhost/vdpa.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'drivers/vhost') diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index 05f5fd2af58f..04375722c0e5 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -358,6 +358,20 @@ static long vhost_vdpa_get_iova_range(struct vhost_vdpa *v, u32 __user *argp) return 0; } +static long vhost_vdpa_get_config_size(struct vhost_vdpa *v, u32 __user *argp) +{ + struct vdpa_device *vdpa = v->vdpa; + const struct vdpa_config_ops *ops = vdpa->config; + u32 size; + + size = ops->get_config_size(vdpa); + + if (copy_to_user(argp, &size, sizeof(size))) + return -EFAULT; + + return 0; +} + static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd, void __user *argp) { @@ -495,6 +509,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, case VHOST_VDPA_GET_IOVA_RANGE: r = vhost_vdpa_get_iova_range(v, argp); break; + case VHOST_VDPA_GET_CONFIG_SIZE: + r = vhost_vdpa_get_config_size(v, argp); + break; default: r = vhost_dev_ioctl(&v->vdev, cmd, argp); if (r == -ENOIOCTLCMD) -- cgit v1.2.3-58-ga151