Commit cef25866 authored by Mike Christie's avatar Mike Christie Committed by Michael S. Tsirkin
Browse files

vhost: add helper to parse userspace vring state/file 



The next patches add new vhost worker ioctls which will need to get a
vhost_virtqueue from a userspace struct which specifies the vq's index.
This moves the vhost_vring_ioctl code to do this to a helper so it can
be shared.

Signed-off-by: default avatarMike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-14-michael.christie@oracle.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 27eca189

drivers/vhost/vhost.c

+22 −7
Original line number Diff line number Diff line
@@ -599,6 +599,27 @@ static struct vhost_worker *vhost_worker_create(struct vhost_dev *dev) 
	return NULL;

}



static int vhost_get_vq_from_user(struct vhost_dev *dev, void __user *argp,

				  struct vhost_virtqueue **vq, u32 *id)

{

	u32 __user *idxp = argp;

	u32 idx;

	long r;



	r = get_user(idx, idxp);

	if (r < 0)

		return r;



	if (idx >= dev->nvqs)

		return -ENOBUFS;



	idx = array_index_nospec(idx, dev->nvqs);



	*vq = dev->vqs[idx];

	*id = idx;

	return 0;

}



/* Caller should have device mutex */

long vhost_dev_set_owner(struct vhost_dev *dev)

{
@@ -1618,21 +1639,15 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg 
	struct file *eventfp, *filep = NULL;

	bool pollstart = false, pollstop = false;

	struct eventfd_ctx *ctx = NULL;

	u32 __user *idxp = argp;

	struct vhost_virtqueue *vq;

	struct vhost_vring_state s;

	struct vhost_vring_file f;

	u32 idx;

	long r;



	r = get_user(idx, idxp);

	r = vhost_get_vq_from_user(d, argp, &vq, &idx);

	if (r < 0)

		return r;

	if (idx >= d->nvqs)

		return -ENOBUFS;



	idx = array_index_nospec(idx, d->nvqs);

	vq = d->vqs[idx];



	if (ioctl == VHOST_SET_VRING_NUM ||

	    ioctl == VHOST_SET_VRING_ADDR) {