1 files changed, 116 insertions, 31 deletions

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 3a5f81a66d34..15a216cdd507 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -295,11 +295,8 @@ static void vhost_vq_meta_reset(struct vhost_dev *d)
 {
 	int i;
 
-	for (i = 0; i < d->nvqs; ++i) {
-		mutex_lock(&d->vqs[i]->mutex);
+	for (i = 0; i < d->nvqs; ++i)
 		__vhost_vq_meta_reset(d->vqs[i]);
-		mutex_unlock(&d->vqs[i]->mutex);
-	}
 }
 
 static void vhost_vq_reset(struct vhost_dev *dev,
@@ -658,7 +655,7 @@ static bool log_access_ok(void __user *log_base, u64 addr, unsigned long sz)
 	    a + (unsigned long)log_base > ULONG_MAX)
 		return false;
 
-	return access_ok(VERIFY_WRITE, log_base + a,
+	return access_ok(log_base + a,
 			 (sz + VHOST_PAGE_SIZE * 8 - 1) / VHOST_PAGE_SIZE / 8);
 }
 
@@ -684,7 +681,7 @@ static bool vq_memory_access_ok(void __user *log_base, struct vhost_umem *umem,
 			return false;
 
 
-		if (!access_ok(VERIFY_WRITE, (void __user *)a,
+		if (!access_ok((void __user *)a,
 				    node->size))
 			return false;
 		else if (log_all && !log_access_ok(log_base,
@@ -895,6 +892,20 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq,
 #define vhost_get_used(vq, x, ptr) \
 	vhost_get_user(vq, x, ptr, VHOST_ADDR_USED)
 
+static void vhost_dev_lock_vqs(struct vhost_dev *d)
+{
+	int i = 0;
+	for (i = 0; i < d->nvqs; ++i)
+		mutex_lock_nested(&d->vqs[i]->mutex, i);
+}
+
+static void vhost_dev_unlock_vqs(struct vhost_dev *d)
+{
+	int i = 0;
+	for (i = 0; i < d->nvqs; ++i)
+		mutex_unlock(&d->vqs[i]->mutex);
+}
+
 static int vhost_new_umem_range(struct vhost_umem *umem,
 				u64 start, u64 size, u64 end,
 				u64 userspace_addr, int perm)
@@ -944,10 +955,7 @@ static void vhost_iotlb_notify_vq(struct vhost_dev *d,
 		if (msg->iova <= vq_msg->iova &&
 		    msg->iova + msg->size - 1 >= vq_msg->iova &&
 		    vq_msg->type == VHOST_IOTLB_MISS) {
-			mutex_lock(&node->vq->mutex);
 			vhost_poll_queue(&node->vq->poll);
-			mutex_unlock(&node->vq->mutex);
-
 			list_del(&node->node);
 			kfree(node);
 		}
@@ -965,10 +973,10 @@ static bool umem_access_ok(u64 uaddr, u64 size, int access)
 		return false;
 
 	if ((access & VHOST_ACCESS_RO) &&
-	    !access_ok(VERIFY_READ, (void __user *)a, size))
+	    !access_ok((void __user *)a, size))
 		return false;
 	if ((access & VHOST_ACCESS_WO) &&
-	    !access_ok(VERIFY_WRITE, (void __user *)a, size))
+	    !access_ok((void __user *)a, size))
 		return false;
 	return true;
 }
@@ -979,6 +987,7 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev,
 	int ret = 0;
 
 	mutex_lock(&dev->mutex);
+	vhost_dev_lock_vqs(dev);
 	switch (msg->type) {
 	case VHOST_IOTLB_UPDATE:
 		if (!dev->iotlb) {
@@ -1012,6 +1021,7 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev,
 		break;
 	}
 
+	vhost_dev_unlock_vqs(dev);
 	mutex_unlock(&dev->mutex);
 
 	return ret;
@@ -1024,8 +1034,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
 	int type, ret;
 
 	ret = copy_from_iter(&type, sizeof(type), from);
-	if (ret != sizeof(type))
+	if (ret != sizeof(type)) {
+		ret = -EINVAL;
 		goto done;
+	}
 
 	switch (type) {
 	case VHOST_IOTLB_MSG:
@@ -1044,8 +1056,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
 
 	iov_iter_advance(from, offset);
 	ret = copy_from_iter(&msg, sizeof(msg), from);
-	if (ret != sizeof(msg))
+	if (ret != sizeof(msg)) {
+		ret = -EINVAL;
 		goto done;
+	}
 	if (vhost_process_iotlb_msg(dev, &msg)) {
 		ret = -EFAULT;
 		goto done;
@@ -1175,10 +1189,10 @@ static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num,
 {
 	size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
 
-	return access_ok(VERIFY_READ, desc, num * sizeof *desc) &&
-	       access_ok(VERIFY_READ, avail,
+	return access_ok(desc, num * sizeof *desc) &&
+	       access_ok(avail,
 			 sizeof *avail + num * sizeof *avail->ring + s) &&
-	       access_ok(VERIFY_WRITE, used,
+	       access_ok(used,
 			sizeof *used + num * sizeof *used->ring + s);
 }
 
@@ -1723,13 +1737,87 @@ static int log_write(void __user *log_base,
 	return r;
 }
 
+static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len)
+{
+	struct vhost_umem *umem = vq->umem;
+	struct vhost_umem_node *u;
+	u64 start, end, l, min;
+	int r;
+	bool hit = false;
+
+	while (len) {
+		min = len;
+		/* More than one GPAs can be mapped into a single HVA. So
+		 * iterate all possible umems here to be safe.
+		 */
+		list_for_each_entry(u, &umem->umem_list, link) {
+			if (u->userspace_addr > hva - 1 + len ||
+			    u->userspace_addr - 1 + u->size < hva)
+				continue;
+			start = max(u->userspace_addr, hva);
+			end = min(u->userspace_addr - 1 + u->size,
+				  hva - 1 + len);
+			l = end - start + 1;
+			r = log_write(vq->log_base,
+				      u->start + start - u->userspace_addr,
+				      l);
+			if (r < 0)
+				return r;
+			hit = true;
+			min = min(l, min);
+		}
+
+		if (!hit)
+			return -EFAULT;
+
+		len -= min;
+		hva += min;
+	}
+
+	return 0;
+}
+
+static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len)
+{
+	struct iovec iov[64];
+	int i, ret;
+
+	if (!vq->iotlb)
+		return log_write(vq->log_base, vq->log_addr + used_offset, len);
+
+	ret = translate_desc(vq, (uintptr_t)vq->used + used_offset,
+			     len, iov, 64, VHOST_ACCESS_WO);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < ret; i++) {
+		ret = log_write_hva(vq,	(uintptr_t)iov[i].iov_base,
+				    iov[i].iov_len);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
-		    unsigned int log_num, u64 len)
+		    unsigned int log_num, u64 len, struct iovec *iov, int count)
 {
 	int i, r;
 
 	/* Make sure data written is seen before log. */
 	smp_wmb();
+
+	if (vq->iotlb) {
+		for (i = 0; i < count; i++) {
+			r = log_write_hva(vq, (uintptr_t)iov[i].iov_base,
+					  iov[i].iov_len);
+			if (r < 0)
+				return r;
+		}
+		return 0;
+	}
+
 	for (i = 0; i < log_num; ++i) {
 		u64 l = min(log[i].len, len);
 		r = log_write(vq->log_base, log[i].addr, l);
@@ -1759,9 +1847,8 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq)
 		smp_wmb();
 		/* Log used flag write. */
 		used = &vq->used->flags;
-		log_write(vq->log_base, vq->log_addr +
-			  (used - (void __user *)vq->used),
-			  sizeof vq->used->flags);
+		log_used(vq, (used - (void __user *)vq->used),
+			 sizeof vq->used->flags);
 		if (vq->log_ctx)
 			eventfd_signal(vq->log_ctx, 1);
 	}
@@ -1779,9 +1866,8 @@ static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event)
 		smp_wmb();
 		/* Log avail event write */
 		used = vhost_avail_event(vq);
-		log_write(vq->log_base, vq->log_addr +
-			  (used - (void __user *)vq->used),
-			  sizeof *vhost_avail_event(vq));
+		log_used(vq, (used - (void __user *)vq->used),
+			 sizeof *vhost_avail_event(vq));
 		if (vq->log_ctx)
 			eventfd_signal(vq->log_ctx, 1);
 	}
@@ -1804,7 +1890,7 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq)
 		goto err;
 	vq->signalled_used_valid = false;
 	if (!vq->iotlb &&
-	    !access_ok(VERIFY_READ, &vq->used->idx, sizeof vq->used->idx)) {
+	    !access_ok(&vq->used->idx, sizeof vq->used->idx)) {
 		r = -EFAULT;
 		goto err;
 	}
@@ -2181,10 +2267,8 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
 		/* Make sure data is seen before log. */
 		smp_wmb();
 		/* Log used ring entry write. */
-		log_write(vq->log_base,
-			  vq->log_addr +
-			   ((void __user *)used - (void __user *)vq->used),
-			  count * sizeof *used);
+		log_used(vq, ((void __user *)used - (void __user *)vq->used),
+			 count * sizeof *used);
 	}
 	old = vq->last_used_idx;
 	new = (vq->last_used_idx += count);
@@ -2223,10 +2307,11 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
 		return -EFAULT;
 	}
 	if (unlikely(vq->log_used)) {
+		/* Make sure used idx is seen before log. */
+		smp_wmb();
 		/* Log used index update. */
-		log_write(vq->log_base,
-			  vq->log_addr + offsetof(struct vring_used, idx),
-			  sizeof vq->used->idx);
+		log_used(vq, offsetof(struct vring_used, idx),
+			 sizeof vq->used->idx);
 		if (vq->log_ctx)
 			eventfd_signal(vq->log_ctx, 1);
 	}