Index: usr.sbin/bhyve/pci_virtio_9p.c
===================================================================
--- usr.sbin/bhyve/pci_virtio_9p.c
+++ usr.sbin/bhyve/pci_virtio_9p.c
@@ -197,27 +197,20 @@
 	struct iovec iov[VT9P_MAX_IOV];
 	struct pci_vt9p_softc *sc;
 	struct pci_vt9p_request *preq;
-	uint16_t idx, n, i;
+	struct vi_req req;
 	uint16_t flags[VT9P_MAX_IOV];
+	uint16_t n;
 
 	sc = vsc;
 
 	while (vq_has_descs(vq)) {
-		n = vq_getchain(vq, &idx, iov, VT9P_MAX_IOV, flags);
+		n = vq_getchain(vq, iov, VT9P_MAX_IOV, &req);
 		preq = calloc(1, sizeof(struct pci_vt9p_request));
 		preq->vsr_sc = sc;
-		preq->vsr_idx = idx;
+		preq->vsr_idx = req.idx;
 		preq->vsr_iov = iov;
 		preq->vsr_niov = n;
-		preq->vsr_respidx = 0;
-
-		/* Count readable descriptors */
-		for (i = 0; i < n; i++) {
-			if (flags[i] & VRING_DESC_F_WRITE)
-				break;
-
-			preq->vsr_respidx++;
-		}
+		preq->vsr_respidx = req.wr_iov - iov;
 
 		for (int i = 0; i < n; i++) {
 			DPRINTF(("vt9p: vt9p_notify(): desc%d base=%p, "
Index: usr.sbin/bhyve/pci_virtio_block.c
===================================================================
--- usr.sbin/bhyve/pci_virtio_block.c
+++ usr.sbin/bhyve/pci_virtio_block.c
@@ -308,11 +308,11 @@
 	int err;
 	ssize_t iolen;
 	int writeop, type;
+	struct vi_req req;
 	struct iovec iov[BLOCKIF_IOV_MAX + 2];
-	uint16_t idx, flags[BLOCKIF_IOV_MAX + 2];
 	struct virtio_blk_discard_write_zeroes *discard;
 
-	n = vq_getchain(vq, &idx, iov, BLOCKIF_IOV_MAX + 2, flags);
+	n = vq_getchain(vq, iov, BLOCKIF_IOV_MAX + 2, &req);
 
 	/*
 	 * The first descriptor will be the read-only fixed header,
@@ -324,16 +324,16 @@
 	 */
 	assert(n >= 2 && n <= BLOCKIF_IOV_MAX + 2);
 
-	io = &sc->vbsc_ios[idx];
-	assert((flags[0] & VRING_DESC_F_WRITE) == 0);
-	assert(iov[0].iov_len == sizeof(struct virtio_blk_hdr));
+	io = &sc->vbsc_ios[req.idx];
+	assert(req.rd_niov != 0);
+	assert(req.rd_iov[0].iov_len == sizeof(struct virtio_blk_hdr));
 	vbh = (struct virtio_blk_hdr *)iov[0].iov_base;
 	memcpy(&io->io_req.br_iov, &iov[1], sizeof(struct iovec) * (n - 2));
 	io->io_req.br_iovcnt = n - 2;
 	io->io_req.br_offset = vbh->vbh_sector * VTBLK_BSIZE;
 	io->io_status = (uint8_t *)iov[--n].iov_base;
-	assert(iov[n].iov_len == 1);
-	assert(flags[n] & VRING_DESC_F_WRITE);
+	assert(req.wr_niov != 0);
+	assert(req.wr_iov[req.wr_niov - 1].iov_len == 1);
 
 	/*
 	 * XXX
@@ -342,16 +342,10 @@
 	 */
 	type = vbh->vbh_type & ~VBH_FLAG_BARRIER;
 	writeop = (type == VBH_OP_WRITE || type == VBH_OP_DISCARD);
+	assert(n == (writeop ? req.rd_niov : req.wr_niov));
 
 	iolen = 0;
 	for (i = 1; i < n; i++) {
-		/*
-		 * - write op implies read-only descriptor,
-		 * - read/ident op implies write-only descriptor,
-		 * therefore test the inverse of the descriptor bit
-		 * to the op.
-		 */
-		assert(((flags[i] & VRING_DESC_F_WRITE) == 0) == writeop);
 		iolen += iov[i].iov_len;
 	}
 	io->io_req.br_resid = iolen;
Index: usr.sbin/bhyve/pci_virtio_console.c
===================================================================
--- usr.sbin/bhyve/pci_virtio_console.c
+++ usr.sbin/bhyve/pci_virtio_console.c
@@ -415,10 +415,10 @@
 	struct pci_vtcon_port *port;
 	struct pci_vtcon_sock *sock = (struct pci_vtcon_sock *)arg;
 	struct vqueue_info *vq;
+	struct vi_req req;
 	struct iovec iov;
 	static char dummybuf[2048];
 	int len, n;
-	uint16_t idx;
 
 	port = sock->vss_port;
 	vq = pci_vtcon_port_to_vq(port, true);
@@ -441,7 +441,7 @@
 	}
 
 	do {
-		n = vq_getchain(vq, &idx, &iov, 1, NULL);
+		n = vq_getchain(vq, &iov, 1, &req);
 		len = readv(sock->vss_conn_fd, &iov, n);
 
 		if (len == 0 || (len < 0 && errno == EWOULDBLOCK)) {
@@ -453,7 +453,7 @@
 			return;
 		}
 
-		vq_relchain(vq, idx, len);
+		vq_relchain(vq, req.idx, len);
 	} while (vq_has_descs(vq));
 
 	vq_endchains(vq, 1);
@@ -572,8 +572,8 @@
     struct pci_vtcon_control *ctrl, const void *payload, size_t len)
 {
 	struct vqueue_info *vq;
+	struct vi_req req;
 	struct iovec iov;
-	uint16_t idx;
 	int n;
 
 	vq = pci_vtcon_port_to_vq(&sc->vsc_control_port, true);
@@ -581,7 +581,7 @@
 	if (!vq_has_descs(vq))
 		return;
 
-	n = vq_getchain(vq, &idx, &iov, 1, NULL);
+	n = vq_getchain(vq, &iov, 1, &req);
 
 	assert(n == 1);
 
@@ -590,7 +590,7 @@
 		memcpy(iov.iov_base + sizeof(struct pci_vtcon_control),
 		     payload, len);
 
-	vq_relchain(vq, idx, sizeof(struct pci_vtcon_control) + len);
+	vq_relchain(vq, req.idx, sizeof(struct pci_vtcon_control) + len);
 	vq_endchains(vq, 1);
 }
     
@@ -601,14 +601,14 @@
 	struct pci_vtcon_softc *sc;
 	struct pci_vtcon_port *port;
 	struct iovec iov[1];
-	uint16_t idx, n;
-	uint16_t flags[8];
+	struct vi_req req;
+	uint16_t n;
 
 	sc = vsc;
 	port = pci_vtcon_vq_to_port(sc, vq);
 
 	while (vq_has_descs(vq)) {
-		n = vq_getchain(vq, &idx, iov, 1, flags);
+		n = vq_getchain(vq, iov, 1, &req);
 		assert(n >= 1);
 		if (port != NULL)
 			port->vsp_cb(port, port->vsp_arg, iov, 1);
@@ -616,7 +616,7 @@
 		/*
 		 * Release this chain and handle more
 		 */
-		vq_relchain(vq, idx, 0);
+		vq_relchain(vq, req.idx, 0);
 	}
 	vq_endchains(vq, 1);	/* Generate interrupt if appropriate. */
 }
Index: usr.sbin/bhyve/pci_virtio_net.c
===================================================================
--- usr.sbin/bhyve/pci_virtio_net.c
+++ usr.sbin/bhyve/pci_virtio_net.c
@@ -248,6 +248,7 @@
 	struct virtio_mrg_rxbuf_info info[VTNET_MAXSEGS];
 	struct iovec iov[VTNET_MAXSEGS + 1];
 	struct vqueue_info *vq;
+	struct vi_req req;
 
 	vq = &sc->vsc_queues[VTNET_RXQ];
 
@@ -288,8 +289,9 @@
 		riov = iov;
 		n_chains = 0;
 		do {
-			int n = vq_getchain(vq, &info[n_chains].idx, riov,
-			    VTNET_MAXSEGS - riov_len, NULL);
+			int n = vq_getchain(vq, riov, VTNET_MAXSEGS - riov_len,
+			    &req);
+			info[n_chains].idx = req.idx;
 
 			if (n == 0) {
 				/*
@@ -435,7 +437,7 @@
 {
 	struct iovec iov[VTNET_MAXSEGS + 1];
 	struct iovec *siov = iov;
-	uint16_t idx;
+	struct vi_req req;
 	ssize_t len;
 	int n;
 
@@ -443,7 +445,7 @@
 	 * Obtain chain of descriptors. The first descriptor also
 	 * contains the virtio-net header.
 	 */
-	n = vq_getchain(vq, &idx, iov, VTNET_MAXSEGS, NULL);
+	n = vq_getchain(vq, iov, VTNET_MAXSEGS, &req);
 	assert(n >= 1 && n <= VTNET_MAXSEGS);
 
 	if (sc->vhdrlen != sc->be_vhdrlen) {
@@ -473,7 +475,7 @@
 	 * Return the processed chain to the guest, reporting
 	 * the number of bytes that we read.
 	 */
-	vq_relchain(vq, idx, len);
+	vq_relchain(vq, req.idx, len);
 }
 
 /* Called on TX kick. */
Index: usr.sbin/bhyve/pci_virtio_rnd.c
===================================================================
--- usr.sbin/bhyve/pci_virtio_rnd.c
+++ usr.sbin/bhyve/pci_virtio_rnd.c
@@ -113,8 +113,8 @@
 {
 	struct iovec iov;
 	struct pci_vtrnd_softc *sc;
+	struct vi_req req;
 	int len;
-	uint16_t idx;
 
 	sc = vsc;
 
@@ -124,7 +124,7 @@
 	}
 
 	while (vq_has_descs(vq)) {
-		vq_getchain(vq, &idx, &iov, 1, NULL);
+		vq_getchain(vq, &iov, 1, &req);
 
 		len = read(sc->vrsc_fd, iov.iov_base, iov.iov_len);
 
@@ -136,7 +136,7 @@
 		/*
 		 * Release this chain and handle more
 		 */
-		vq_relchain(vq, idx, len);
+		vq_relchain(vq, req.idx, len);
 	}
 	vq_endchains(vq, 1);	/* Generate interrupt if appropriate. */
 }
Index: usr.sbin/bhyve/pci_virtio_scsi.c
===================================================================
--- usr.sbin/bhyve/pci_virtio_scsi.c
+++ usr.sbin/bhyve/pci_virtio_scsi.c
@@ -558,7 +558,8 @@
 {
 	struct pci_vtscsi_softc *sc;
 	struct iovec iov[VTSCSI_MAXSEG];
-	uint16_t idx, n;
+	struct vi_req req;
+	uint16_t n;
 	void *buf = NULL;
 	size_t bufsize;
 	int iolen;
@@ -566,7 +567,7 @@
 	sc = vsc;
 
 	while (vq_has_descs(vq)) {
-		n = vq_getchain(vq, &idx, iov, VTSCSI_MAXSEG, NULL);
+		n = vq_getchain(vq, iov, VTSCSI_MAXSEG, &req);
 		bufsize = iov_to_buf(iov, n, &buf);
 		iolen = pci_vtscsi_control_handle(sc, buf, bufsize);
 		buf_to_iov(buf + bufsize - iolen, iolen, iov, n,
@@ -575,7 +576,7 @@
 		/*
 		 * Release this chain and handle more
 		 */
-		vq_relchain(vq, idx, iolen);
+		vq_relchain(vq, req.idx, iolen);
 	}
 	vq_endchains(vq, 1);	/* Generate interrupt if appropriate. */
 	free(buf);
@@ -595,33 +596,23 @@
 	struct pci_vtscsi_queue *q;
 	struct pci_vtscsi_request *req;
 	struct iovec iov[VTSCSI_MAXSEG];
-	uint16_t flags[VTSCSI_MAXSEG];
-	uint16_t idx, n, i;
-	int readable;
+	struct vi_req vireq;
+	uint16_t n;
 
 	sc = vsc;
 	q = &sc->vss_queues[vq->vq_num - 2];
 
 	while (vq_has_descs(vq)) {
-		readable = 0;
-		n = vq_getchain(vq, &idx, iov, VTSCSI_MAXSEG, flags);
-
-		/* Count readable descriptors */
-		for (i = 0; i < n; i++) {
-			if (flags[i] & VRING_DESC_F_WRITE)
-				break;
-
-			readable++;
-		}
+		n = vq_getchain(vq, iov, VTSCSI_MAXSEG, &vireq);
 
 		req = calloc(1, sizeof(struct pci_vtscsi_request));
-		req->vsr_idx = idx;
+		req->vsr_idx = vireq.idx;
 		req->vsr_queue = q;
-		req->vsr_niov_in = readable;
-		req->vsr_niov_out = n - readable;
-		memcpy(req->vsr_iov_in, iov,
+		req->vsr_niov_in = vireq.rd_niov;
+		req->vsr_niov_out = vireq.wr_niov;
+		memcpy(req->vsr_iov_in, vireq.rd_iov,
 		    req->vsr_niov_in * sizeof(struct iovec));
-		memcpy(req->vsr_iov_out, iov + readable,
+		memcpy(req->vsr_iov_out, vireq.wr_iov,
 		    req->vsr_niov_out * sizeof(struct iovec));
 
 		pthread_mutex_lock(&q->vsq_mtx);
@@ -629,7 +620,8 @@
 		pthread_cond_signal(&q->vsq_cv);
 		pthread_mutex_unlock(&q->vsq_mtx);
 
-		DPRINTF(("virtio-scsi: request <idx=%d> enqueued", idx));
+		DPRINTF(("virtio-scsi: request <idx=%d> enqueuedvi",
+		    vireq.idx));
 	}
 }
 
Index: usr.sbin/bhyve/virtio.h
===================================================================
--- usr.sbin/bhyve/virtio.h
+++ usr.sbin/bhyve/virtio.h
@@ -371,6 +371,18 @@
 }
 
 struct iovec;
+
+/*
+ * Request description returned by vq_getchain
+ */
+struct vi_req {
+	struct iovec *rd_iov;	/* driver-to-device buffer iovec */
+	struct iovec *wr_iov;	/* device-to-driver buffer iovec */
+	int rd_niov;		/* num of driver-to-device iovec */
+	int wr_niov;		/* num of driver-to-device iovec */
+	unsigned int idx;	/* ring index */
+};
+
 void	vi_softc_linkup(struct virtio_softc *vs, struct virtio_consts *vc,
 			void *dev_softc, struct pci_devinst *pi,
 			struct vqueue_info *queues);
@@ -378,8 +390,8 @@
 void	vi_reset_dev(struct virtio_softc *);
 void	vi_set_io_bar(struct virtio_softc *, int);
 
-int	vq_getchain(struct vqueue_info *vq, uint16_t *pidx,
-		    struct iovec *iov, int n_iov, uint16_t *flags);
+int	vq_getchain(struct vqueue_info *vq, struct iovec *iov, int niov,
+	    struct vi_req *reqp);
 void	vq_retchains(struct vqueue_info *vq, uint16_t n_chains);
 void	vq_relchain_prepare(struct vqueue_info *vq, uint16_t idx,
 			    uint32_t iolen);
Index: usr.sbin/bhyve/virtio.c
===================================================================
--- usr.sbin/bhyve/virtio.c
+++ usr.sbin/bhyve/virtio.c
@@ -213,15 +213,23 @@
  * descriptor.
  */
 static inline void
-_vq_record(int i, volatile struct vring_desc *vd, struct vmctx *ctx,
-	   struct iovec *iov, int n_iov, uint16_t *flags) {
+_vq_record(struct virtio_softc *vs, int i, volatile struct vring_desc *vd,
+	   struct vmctx *ctx, struct iovec *iov, int n_iov,
+	   struct vi_req *reqp) {
 
 	if (i >= n_iov)
 		return;
 	iov[i].iov_base = paddr_guest2host(ctx, vd->addr, vd->len);
 	iov[i].iov_len = vd->len;
-	if (flags != NULL)
-		flags[i] = vd->flags;
+	if (vd->flags & VRING_DESC_F_WRITE) {
+		if (reqp->wr_iov == NULL)
+			reqp->wr_iov = &iov[i];
+		reqp->wr_niov++;
+	} else {
+		if (reqp->rd_iov == NULL)
+			reqp->rd_iov = &iov[i];
+		reqp->rd_niov++;
+	}
 }
 #define	VQ_MAX_DESCRIPTORS	512	/* see below */
 
@@ -253,11 +261,6 @@
  * a larger iov array if needed, or supply a zero length to find
  * out how much space is needed).
  *
- * If you want to verify the WRITE flag on each descriptor, pass a
- * non-NULL "flags" pointer to an array of "uint16_t" of the same size
- * as n_iov and we'll copy each "flags" field after unwinding any
- * indirects.
- *
  * If some descriptor(s) are invalid, this prints a diagnostic message
  * and returns -1.  If no descriptors are ready now it simply returns 0.
  *
@@ -265,12 +268,13 @@
  * that vq_has_descs() does one).
  */
 int
-vq_getchain(struct vqueue_info *vq, uint16_t *pidx,
-	    struct iovec *iov, int n_iov, uint16_t *flags)
+vq_getchain(struct vqueue_info *vq, struct iovec *iov, int niov,
+	    struct vi_req *reqp)
 {
 	int i;
 	u_int ndesc, n_indir;
 	u_int idx, next;
+	struct vi_req req = { 0 };
 	volatile struct vring_desc *vdir, *vindir, *vp;
 	struct vmctx *ctx;
 	struct virtio_softc *vs;
@@ -313,7 +317,7 @@
 	 * index, but we just abort if the count gets excessive.
 	 */
 	ctx = vs->vs_pi->pi_vmctx;
-	*pidx = next = vq->vq_avail->ring[idx & (vq->vq_qsize - 1)];
+	req.idx = next = vq->vq_avail->ring[idx & (vq->vq_qsize - 1)];
 	vq->vq_last_avail++;
 	for (i = 0; i < VQ_MAX_DESCRIPTORS; next = vdir->next) {
 		if (next >= vq->vq_qsize) {
@@ -325,7 +329,7 @@
 		}
 		vdir = &vq->vq_desc[next];
 		if ((vdir->flags & VRING_DESC_F_INDIRECT) == 0) {
-			_vq_record(i, vdir, ctx, iov, n_iov, flags);
+			_vq_record(vs, i, vdir, ctx, iov, niov, &req);
 			i++;
 		} else if ((vs->vs_vc->vc_hv_caps &
 		    VIRTIO_RING_F_INDIRECT_DESC) == 0) {
@@ -362,7 +366,7 @@
 					    name);
 					return (-1);
 				}
-				_vq_record(i, vp, ctx, iov, n_iov, flags);
+				_vq_record(vs, i, vp, ctx, iov, niov, &req);
 				if (++i > VQ_MAX_DESCRIPTORS)
 					goto loopy;
 				if ((vp->flags & VRING_DESC_F_NEXT) == 0)
@@ -378,13 +382,18 @@
 			}
 		}
 		if ((vdir->flags & VRING_DESC_F_NEXT) == 0)
-			return (i);
+			goto done;
 	}
+
 loopy:
 	EPRINTLN(
 	    "%s: descriptor loop? count > %d - driver confused?",
 	    name, i);
 	return (-1);
+
+done:
+	*reqp = req;
+	return (i);
 }
 
 /*