X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fvhost%2Fvhost.c;h=ad2146a9ab2d4b19cca5469402c203ade61e8545;hb=b9d85451ddd4e7f2d6280506f6fe7f1924356924;hp=eec2f11809ff2463d2a714224925af9c679fead1;hpb=978ab6a009e6691375a0b6f8a44ebbb471a64b6d;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index eec2f11809ff..ad2146a9ab2d 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -819,7 +819,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp)
 		BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE);
 		if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) ||
 		    (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) ||
-		    (a.log_guest_addr & (sizeof(u64) - 1))) {
+		    (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) {
 			r = -EINVAL;
 			break;
 		}
@@ -1369,7 +1369,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq,
 	/* Grab the next descriptor number they're advertising, and increment
 	 * the index we've seen. */
 	if (unlikely(__get_user(ring_head,
-				&vq->avail->ring[last_avail_idx % vq->num]))) {
+				&vq->avail->ring[last_avail_idx & (vq->num - 1)]))) {
 		vq_err(vq, "Failed to read head: idx %d address %p\n",
 		       last_avail_idx,
 		       &vq->avail->ring[last_avail_idx % vq->num]);
@@ -1489,7 +1489,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
 	u16 old, new;
 	int start;
 
-	start = vq->last_used_idx % vq->num;
+	start = vq->last_used_idx & (vq->num - 1);
 	used = vq->used->ring + start;
 	if (count == 1) {
 		if (__put_user(heads[0].id, &used->id)) {
@@ -1531,7 +1531,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
 {
 	int start, n, r;
 
-	start = vq->last_used_idx % vq->num;
+	start = vq->last_used_idx & (vq->num - 1);
 	n = vq->num - start;
 	if (n < count) {
 		r = __vhost_add_used_n(vq, heads, n);