From: dlg <dlg@openbsd.org>
Date: Sun, 30 Jul 2023 01:59:23 +0000 (+0000)
Subject: add bus_dmamap_syncs around tx ring handling.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=69cf50f825e13f50285816f85ebabe8b6f37db4a;p=openbsd

add bus_dmamap_syncs around tx ring handling.

this copies the dmamem wrapper from ixl (which has been copied
around lots of other places too) so it makes the bus_dma ops around
them more consistent with other drivers. before this vmx would use
the bus dma api to allocate physical memory, but then free the
dmamap so it wasnt available for use with bus_dmamap_sync().
---

diff --git a/sys/dev/pci/if_vmx.c b/sys/dev/pci/if_vmx.c
index ffceccf14a6..050de9a0a45 100644
--- a/sys/dev/pci/if_vmx.c
+++ b/sys/dev/pci/if_vmx.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_vmx.c,v 1.72 2023/07/30 01:41:05 dlg Exp $	*/
+/*	$OpenBSD: if_vmx.c,v 1.73 2023/07/30 01:59:23 dlg Exp $	*/
 
 /*
  * Copyright (c) 2013 Tsubai Masanari
@@ -61,9 +61,23 @@
 #define VMX_RX_GEN	htole32(VMXNET3_RX_GEN_M << VMXNET3_RX_GEN_S)
 #define VMX_RXC_GEN	htole32(VMXNET3_RXC_GEN_M << VMXNET3_RXC_GEN_S)
 
+struct vmx_dmamem {
+	bus_dmamap_t		vdm_map;
+	bus_dma_segment_t	vdm_seg;
+	int			vdm_nsegs;
+	size_t			vdm_size;
+	caddr_t			vdm_kva;
+};
+
+#define VMX_DMA_MAP(_vdm)	((_vdm)->vdm_map)
+#define VMX_DMA_DVA(_vdm)	((_vdm)->vdm_map->dm_segs[0].ds_addr)
+#define VMX_DMA_KVA(_vdm)	((void *)(_vdm)->vdm_kva)
+#define VMX_DMA_LEN(_vdm)	((_vdm)->vdm_size)
+
 struct vmxnet3_softc;
 
 struct vmxnet3_txring {
+	struct vmx_dmamem dmamem;
 	struct mbuf *m[NTXDESC];
 	bus_dmamap_t dmap[NTXDESC];
 	struct vmxnet3_txdesc *txd;
@@ -86,6 +100,7 @@ struct vmxnet3_rxring {
 };
 
 struct vmxnet3_comp_ring {
+	struct vmx_dmamem dmamem;
 	union {
 		struct vmxnet3_txcompdesc *txcd;
 		struct vmxnet3_rxcompdesc *rxcd;
@@ -194,6 +209,12 @@ void vmxnet3_media_status(struct ifnet *, struct ifmediareq *);
 int vmxnet3_media_change(struct ifnet *);
 void *vmxnet3_dma_allocmem(struct vmxnet3_softc *, u_int, u_int, bus_addr_t *);
 
+static int	vmx_dmamem_alloc(struct vmxnet3_softc *, struct vmx_dmamem *,
+                    bus_size_t, u_int);
+#ifdef notyet
+static void	vmx_dmamem_free(struct vmxnet3_softc *, struct vmx_dmamem *);
+#endif
+
 #if NKSTAT > 0
 static void	vmx_kstat_init(struct vmxnet3_softc *);
 static void	vmx_kstat_txstats(struct vmxnet3_softc *,
@@ -533,18 +554,18 @@ vmxnet3_alloc_txring(struct vmxnet3_softc *sc, int queue, int intr)
 	struct vmxnet3_txq_shared *ts;
 	struct vmxnet3_txring *ring = &tq->cmd_ring;
 	struct vmxnet3_comp_ring *comp_ring = &tq->comp_ring;
-	bus_addr_t pa, comp_pa;
 	int idx;
 
 	tq->queue = queue;
 
-	ring->txd = vmxnet3_dma_allocmem(sc, NTXDESC * sizeof ring->txd[0], 512, &pa);
-	if (ring->txd == NULL)
+	if (vmx_dmamem_alloc(sc, &ring->dmamem,
+	    NTXDESC * sizeof(struct vmxnet3_txdesc), 512) != 0)
 		return -1;
-	comp_ring->txcd = vmxnet3_dma_allocmem(sc,
-	    NTXCOMPDESC * sizeof comp_ring->txcd[0], 512, &comp_pa);
-	if (comp_ring->txcd == NULL)
+	ring->txd = VMX_DMA_KVA(&ring->dmamem);
+	if (vmx_dmamem_alloc(sc, &comp_ring->dmamem,
+	    NTXCOMPDESC * sizeof(comp_ring->txcd[0]), 512) != 0)
 		return -1;
+	comp_ring->txcd = VMX_DMA_KVA(&comp_ring->dmamem);
 
 	for (idx = 0; idx < NTXDESC; idx++) {
 		if (bus_dmamap_create(sc->sc_dmat, JUMBO_LEN, NTXSEGS,
@@ -556,9 +577,9 @@ vmxnet3_alloc_txring(struct vmxnet3_softc *sc, int queue, int intr)
 	bzero(ts, sizeof *ts);
 	ts->npending = 0;
 	ts->intr_threshold = 1;
-	ts->cmd_ring = pa;
+	ts->cmd_ring = VMX_DMA_DVA(&ring->dmamem);
 	ts->cmd_ring_len = NTXDESC;
-	ts->comp_ring = comp_pa;
+	ts->comp_ring = VMX_DMA_DVA(&comp_ring->dmamem);
 	ts->comp_ring_len = NTXCOMPDESC;
 	ts->driver_data = ~0ULL;
 	ts->driver_data_len = 0;
@@ -630,8 +651,14 @@ vmxnet3_txinit(struct vmxnet3_softc *sc, struct vmxnet3_txqueue *tq)
 	ring->gen = VMX_TX_GEN;
 	comp_ring->next = 0;
 	comp_ring->gen = VMX_TXC_GEN;
-	bzero(ring->txd, NTXDESC * sizeof ring->txd[0]);
-	bzero(comp_ring->txcd, NTXCOMPDESC * sizeof comp_ring->txcd[0]);
+	memset(VMX_DMA_KVA(&ring->dmamem), 0,
+	    VMX_DMA_LEN(&ring->dmamem));
+	bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&ring->dmamem),
+	    0, VMX_DMA_LEN(&ring->dmamem), BUS_DMASYNC_PREWRITE);
+	memset(VMX_DMA_KVA(&comp_ring->dmamem), 0,
+	    VMX_DMA_LEN(&comp_ring->dmamem));
+	bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&comp_ring->dmamem),
+	    0, VMX_DMA_LEN(&comp_ring->dmamem), BUS_DMASYNC_PREREAD);
 }
 
 void
@@ -733,8 +760,14 @@ void
 vmxnet3_txstop(struct vmxnet3_softc *sc, struct vmxnet3_txqueue *tq)
 {
 	struct vmxnet3_txring *ring = &tq->cmd_ring;
+	struct vmxnet3_comp_ring *comp_ring = &tq->comp_ring;
 	int idx;
 
+	bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&comp_ring->dmamem),
+	    0, VMX_DMA_LEN(&comp_ring->dmamem), BUS_DMASYNC_POSTREAD);
+	bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&ring->dmamem),
+	    0, VMX_DMA_LEN(&ring->dmamem), BUS_DMASYNC_POSTWRITE);
+
 	for (idx = 0; idx < NTXDESC; idx++) {
 		if (ring->m[idx]) {
 			bus_dmamap_unload(sc->sc_dmat, ring->dmap[idx]);
@@ -939,7 +972,9 @@ vmxnet3_txintr(struct vmxnet3_softc *sc, struct vmxnet3_txqueue *tq)
 	next = comp_ring->next;
 	rgen = comp_ring->gen;
 
-	/* postread */
+	bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&comp_ring->dmamem),
+	    0, VMX_DMA_LEN(&comp_ring->dmamem), BUS_DMASYNC_POSTREAD);
+
 	do {
 		txcd = &comp_ring->txcd[next];
 		if ((txcd->txc_word3 & VMX_TXC_GEN) != rgen)
@@ -964,7 +999,9 @@ vmxnet3_txintr(struct vmxnet3_softc *sc, struct vmxnet3_txqueue *tq)
 		cons++;
 		cons %= NTXDESC;
 	} while (cons != prod);
-	/* preread */
+
+	bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&comp_ring->dmamem),
+	    0, VMX_DMA_LEN(&comp_ring->dmamem), BUS_DMASYNC_PREREAD);
 
 	comp_ring->next = next;
 	comp_ring->gen = rgen;
@@ -1342,6 +1379,9 @@ vmxnet3_start(struct ifqueue *ifq)
 		free += NTXDESC;
 	free -= prod;
 
+	bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&ring->dmamem),
+	    0, VMX_DMA_LEN(&ring->dmamem), BUS_DMASYNC_POSTWRITE);
+
 	rgen = ring->gen;
 
 	for (;;) {
@@ -1398,13 +1438,18 @@ vmxnet3_start(struct ifqueue *ifq)
 
 		ring->prod = prod;
 		/* Change the ownership by flipping the "generation" bit */
-		membar_producer();
+		bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&ring->dmamem),
+		    0, VMX_DMA_LEN(&ring->dmamem),
+		    BUS_DMASYNC_PREWRITE|BUS_DMASYNC_POSTWRITE);
 		sop->tx_word2 ^= VMX_TX_GEN;
 
 		free -= i;
 		post = 1;
 	}
 
+	bus_dmamap_sync(sc->sc_dmat, VMX_DMA_MAP(&ring->dmamem),
+	    0, VMX_DMA_LEN(&ring->dmamem), BUS_DMASYNC_PREWRITE);
+
 	if (!post)
 		return;
 
@@ -1474,6 +1519,49 @@ vmxnet3_dma_allocmem(struct vmxnet3_softc *sc, u_int size, u_int align, bus_addr
 	return va;
 }
 
+static int
+vmx_dmamem_alloc(struct vmxnet3_softc *sc, struct vmx_dmamem *vdm,
+    bus_size_t size, u_int align)
+{
+	vdm->vdm_size = size;
+
+	if (bus_dmamap_create(sc->sc_dmat, vdm->vdm_size, 1,
+	    vdm->vdm_size, 0,
+	    BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW | BUS_DMA_64BIT,
+	    &vdm->vdm_map) != 0)
+		return (1);
+	if (bus_dmamem_alloc(sc->sc_dmat, vdm->vdm_size,
+	    align, 0, &vdm->vdm_seg, 1, &vdm->vdm_nsegs,
+	    BUS_DMA_WAITOK | BUS_DMA_ZERO) != 0)
+		goto destroy;
+	if (bus_dmamem_map(sc->sc_dmat, &vdm->vdm_seg, vdm->vdm_nsegs,
+	    vdm->vdm_size, &vdm->vdm_kva, BUS_DMA_WAITOK) != 0)
+		goto free;
+	if (bus_dmamap_load(sc->sc_dmat, vdm->vdm_map, vdm->vdm_kva,
+	    vdm->vdm_size, NULL, BUS_DMA_WAITOK) != 0)
+		goto unmap;
+
+	return (0);
+unmap:
+	bus_dmamem_unmap(sc->sc_dmat, vdm->vdm_kva, vdm->vdm_size);
+free:
+	bus_dmamem_free(sc->sc_dmat, &vdm->vdm_seg, 1);
+destroy:
+	bus_dmamap_destroy(sc->sc_dmat, vdm->vdm_map);
+	return (1);
+}
+
+#ifdef notyet
+static void
+vmx_dmamem_free(struct vmxnet3_softc *sc, struct vmx_dmamem *vdm)
+{
+	bus_dmamap_unload(sc->sc_dmat, vdm->vdm_map);
+	bus_dmamem_unmap(sc->sc_dmat, vdm->vdm_kva, vdm->vdm_size);
+	bus_dmamem_free(sc->sc_dmat, &vdm->vdm_seg, 1);
+	bus_dmamap_destroy(sc->sc_dmat, vdm->vdm_map);
+}
+#endif
+
 #if NKSTAT > 0
 /*
  * "hardware" counters are exported as separate kstats for each tx