From: sf <sf@openbsd.org>
Date: Sat, 3 Jun 2017 08:50:38 +0000 (+0000)
Subject: vioblk/virtio: Re-arrange some struct members
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=a28b3ce1090f870d6a9d5b7d1bce6523f93a2e59;p=openbsd

vioblk/virtio: Re-arrange some struct members

This reduces holes/padding and makes the structs smaller.
---

diff --git a/sys/dev/pv/vioblk.c b/sys/dev/pv/vioblk.c
index 64552e3e0ec..cf8a0337fc6 100644
--- a/sys/dev/pv/vioblk.c
+++ b/sys/dev/pv/vioblk.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vioblk.c,v 1.7 2017/05/30 19:28:09 sf Exp $	*/
+/*	$OpenBSD: vioblk.c,v 1.8 2017/06/03 08:50:38 sf Exp $	*/
 
 /*
  * Copyright (c) 2012 Stefan Fritsch.
@@ -87,12 +87,13 @@ struct virtio_feature_name vioblk_feature_names[] = {
 struct virtio_blk_req {
 	struct virtio_blk_req_hdr	 vr_hdr;
 	uint8_t				 vr_status;
-	struct scsi_xfer		*vr_xs;
+#define VR_DMA_END	offsetof(struct virtio_blk_req, vr_qe_index)
+	int16_t				 vr_qe_index;
 	int				 vr_len;
+	struct scsi_xfer		*vr_xs;
 	bus_dmamap_t			 vr_cmdsts;
 	bus_dmamap_t			 vr_payload;
 	SLIST_ENTRY(virtio_blk_req)	 vr_list;
-	int				 vr_qe_index;
 };
 
 struct vioblk_softc {
@@ -710,8 +711,7 @@ vioblk_alloc_reqs(struct vioblk_softc *sc, int qsize)
 		vr->vr_len = VIOBLK_DONE;
 
 		r = bus_dmamap_create(sc->sc_virtio->sc_dmat,
-		    offsetof(struct virtio_blk_req, vr_xs), 1,
-		    offsetof(struct virtio_blk_req, vr_xs), 0,
+		    VR_DMA_END, 1, VR_DMA_END, 0,
 		    BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW, &vr->vr_cmdsts);
 		if (r != 0) {
 			printf("cmd dmamap creation failed, err %d\n", r);
@@ -719,8 +719,7 @@ vioblk_alloc_reqs(struct vioblk_softc *sc, int qsize)
 			goto err_reqs;
 		}
 		r = bus_dmamap_load(sc->sc_virtio->sc_dmat, vr->vr_cmdsts,
-		    &vr->vr_hdr, offsetof(struct virtio_blk_req, vr_xs), NULL,
-		    BUS_DMA_NOWAIT);
+		    &vr->vr_hdr, VR_DMA_END, NULL, BUS_DMA_NOWAIT);
 		if (r != 0) {
 			printf("command dmamap load failed, err %d\n", r);
 			nreqs = i;
diff --git a/sys/dev/pv/virtiovar.h b/sys/dev/pv/virtiovar.h
index 7b8a2f04d62..4b1f71c7e37 100644
--- a/sys/dev/pv/virtiovar.h
+++ b/sys/dev/pv/virtiovar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: virtiovar.h,v 1.5 2017/05/30 12:47:47 krw Exp $	*/
+/*	$OpenBSD: virtiovar.h,v 1.6 2017/06/03 08:50:38 sf Exp $	*/
 /*	$NetBSD: virtiovar.h,v 1.1 2011/10/30 12:12:21 hannken Exp $	*/
 
 /*
@@ -86,9 +86,9 @@ struct vq_entry {
 
 	/* The following are used only in the `head' entry */
 	int16_t			 qe_next;	/* next enq slot */
-	struct vring_desc	*qe_desc_base;	/* pointer to vd array */
 	int16_t			 qe_indirect;	/* 1 if using indirect */
 	int16_t			 qe_vr_index;	/* index in sc_reqs array */
+	struct vring_desc	*qe_desc_base;	/* pointer to vd array */
 };
 
 struct virtqueue {