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Note: File does not exist in v3.1.
   1/* sunvnet.c: Sun LDOM Virtual Network Driver.
   2 *
   3 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
   4 * Copyright (C) 2016 Oracle. All rights reserved.
   5 */
   6
   7#include <linux/module.h>
   8#include <linux/kernel.h>
   9#include <linux/types.h>
  10#include <linux/slab.h>
  11#include <linux/delay.h>
  12#include <linux/init.h>
  13#include <linux/netdevice.h>
  14#include <linux/ethtool.h>
  15#include <linux/etherdevice.h>
  16#include <linux/mutex.h>
  17#include <linux/highmem.h>
  18#include <linux/if_vlan.h>
  19#define CREATE_TRACE_POINTS
  20#include <trace/events/sunvnet.h>
  21
  22#if IS_ENABLED(CONFIG_IPV6)
  23#include <linux/icmpv6.h>
  24#endif
  25
  26#include <net/ip.h>
  27#include <net/icmp.h>
  28#include <net/route.h>
  29
  30#include <asm/vio.h>
  31#include <asm/ldc.h>
  32
  33#include "sunvnet_common.h"
  34
  35/* Heuristic for the number of times to exponentially backoff and
  36 * retry sending an LDC trigger when EAGAIN is encountered
  37 */
  38#define	VNET_MAX_RETRIES	10
  39
  40static int __vnet_tx_trigger(struct vnet_port *port, u32 start);
  41static void vnet_port_reset(struct vnet_port *port);
  42
  43static inline u32 vnet_tx_dring_avail(struct vio_dring_state *dr)
  44{
  45	return vio_dring_avail(dr, VNET_TX_RING_SIZE);
  46}
  47
  48static int vnet_handle_unknown(struct vnet_port *port, void *arg)
  49{
  50	struct vio_msg_tag *pkt = arg;
  51
  52	pr_err("Received unknown msg [%02x:%02x:%04x:%08x]\n",
  53	       pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
  54	pr_err("Resetting connection\n");
  55
  56	ldc_disconnect(port->vio.lp);
  57
  58	return -ECONNRESET;
  59}
  60
  61static int vnet_port_alloc_tx_ring(struct vnet_port *port);
  62
  63int sunvnet_send_attr_common(struct vio_driver_state *vio)
  64{
  65	struct vnet_port *port = to_vnet_port(vio);
  66	struct net_device *dev = VNET_PORT_TO_NET_DEVICE(port);
  67	struct vio_net_attr_info pkt;
  68	int framelen = ETH_FRAME_LEN;
  69	int i, err;
  70
  71	err = vnet_port_alloc_tx_ring(to_vnet_port(vio));
  72	if (err)
  73		return err;
  74
  75	memset(&pkt, 0, sizeof(pkt));
  76	pkt.tag.type = VIO_TYPE_CTRL;
  77	pkt.tag.stype = VIO_SUBTYPE_INFO;
  78	pkt.tag.stype_env = VIO_ATTR_INFO;
  79	pkt.tag.sid = vio_send_sid(vio);
  80	if (vio_version_before(vio, 1, 2))
  81		pkt.xfer_mode = VIO_DRING_MODE;
  82	else
  83		pkt.xfer_mode = VIO_NEW_DRING_MODE;
  84	pkt.addr_type = VNET_ADDR_ETHERMAC;
  85	pkt.ack_freq = 0;
  86	for (i = 0; i < 6; i++)
  87		pkt.addr |= (u64)dev->dev_addr[i] << ((5 - i) * 8);
  88	if (vio_version_after(vio, 1, 3)) {
  89		if (port->rmtu) {
  90			port->rmtu = min(VNET_MAXPACKET, port->rmtu);
  91			pkt.mtu = port->rmtu;
  92		} else {
  93			port->rmtu = VNET_MAXPACKET;
  94			pkt.mtu = port->rmtu;
  95		}
  96		if (vio_version_after_eq(vio, 1, 6))
  97			pkt.options = VIO_TX_DRING;
  98	} else if (vio_version_before(vio, 1, 3)) {
  99		pkt.mtu = framelen;
 100	} else { /* v1.3 */
 101		pkt.mtu = framelen + VLAN_HLEN;
 102	}
 103
 104	pkt.cflags = 0;
 105	if (vio_version_after_eq(vio, 1, 7) && port->tso) {
 106		pkt.cflags |= VNET_LSO_IPV4_CAPAB;
 107		if (!port->tsolen)
 108			port->tsolen = VNET_MAXTSO;
 109		pkt.ipv4_lso_maxlen = port->tsolen;
 110	}
 111
 112	pkt.plnk_updt = PHYSLINK_UPDATE_NONE;
 113
 114	viodbg(HS, "SEND NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
 115	       "ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] mtu[%llu] "
 116	       "cflags[0x%04x] lso_max[%u]\n",
 117	       pkt.xfer_mode, pkt.addr_type,
 118	       (unsigned long long)pkt.addr,
 119	       pkt.ack_freq, pkt.plnk_updt, pkt.options,
 120	       (unsigned long long)pkt.mtu, pkt.cflags, pkt.ipv4_lso_maxlen);
 121
 122	return vio_ldc_send(vio, &pkt, sizeof(pkt));
 123}
 124EXPORT_SYMBOL_GPL(sunvnet_send_attr_common);
 125
 126static int handle_attr_info(struct vio_driver_state *vio,
 127			    struct vio_net_attr_info *pkt)
 128{
 129	struct vnet_port *port = to_vnet_port(vio);
 130	u64	localmtu;
 131	u8	xfer_mode;
 132
 133	viodbg(HS, "GOT NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
 134	       "ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] mtu[%llu] "
 135	       " (rmtu[%llu]) cflags[0x%04x] lso_max[%u]\n",
 136	       pkt->xfer_mode, pkt->addr_type,
 137	       (unsigned long long)pkt->addr,
 138	       pkt->ack_freq, pkt->plnk_updt, pkt->options,
 139	       (unsigned long long)pkt->mtu, port->rmtu, pkt->cflags,
 140	       pkt->ipv4_lso_maxlen);
 141
 142	pkt->tag.sid = vio_send_sid(vio);
 143
 144	xfer_mode = pkt->xfer_mode;
 145	/* for version < 1.2, VIO_DRING_MODE = 0x3 and no bitmask */
 146	if (vio_version_before(vio, 1, 2) && xfer_mode == VIO_DRING_MODE)
 147		xfer_mode = VIO_NEW_DRING_MODE;
 148
 149	/* MTU negotiation:
 150	 *	< v1.3 - ETH_FRAME_LEN exactly
 151	 *	> v1.3 - MIN(pkt.mtu, VNET_MAXPACKET, port->rmtu) and change
 152	 *			pkt->mtu for ACK
 153	 *	= v1.3 - ETH_FRAME_LEN + VLAN_HLEN exactly
 154	 */
 155	if (vio_version_before(vio, 1, 3)) {
 156		localmtu = ETH_FRAME_LEN;
 157	} else if (vio_version_after(vio, 1, 3)) {
 158		localmtu = port->rmtu ? port->rmtu : VNET_MAXPACKET;
 159		localmtu = min(pkt->mtu, localmtu);
 160		pkt->mtu = localmtu;
 161	} else { /* v1.3 */
 162		localmtu = ETH_FRAME_LEN + VLAN_HLEN;
 163	}
 164	port->rmtu = localmtu;
 165
 166	/* LSO negotiation */
 167	if (vio_version_after_eq(vio, 1, 7))
 168		port->tso &= !!(pkt->cflags & VNET_LSO_IPV4_CAPAB);
 169	else
 170		port->tso = false;
 171	if (port->tso) {
 172		if (!port->tsolen)
 173			port->tsolen = VNET_MAXTSO;
 174		port->tsolen = min(port->tsolen, pkt->ipv4_lso_maxlen);
 175		if (port->tsolen < VNET_MINTSO) {
 176			port->tso = false;
 177			port->tsolen = 0;
 178			pkt->cflags &= ~VNET_LSO_IPV4_CAPAB;
 179		}
 180		pkt->ipv4_lso_maxlen = port->tsolen;
 181	} else {
 182		pkt->cflags &= ~VNET_LSO_IPV4_CAPAB;
 183		pkt->ipv4_lso_maxlen = 0;
 184	}
 185
 186	/* for version >= 1.6, ACK packet mode we support */
 187	if (vio_version_after_eq(vio, 1, 6)) {
 188		pkt->xfer_mode = VIO_NEW_DRING_MODE;
 189		pkt->options = VIO_TX_DRING;
 190	}
 191
 192	if (!(xfer_mode | VIO_NEW_DRING_MODE) ||
 193	    pkt->addr_type != VNET_ADDR_ETHERMAC ||
 194	    pkt->mtu != localmtu) {
 195		viodbg(HS, "SEND NET ATTR NACK\n");
 196
 197		pkt->tag.stype = VIO_SUBTYPE_NACK;
 198
 199		(void)vio_ldc_send(vio, pkt, sizeof(*pkt));
 200
 201		return -ECONNRESET;
 202	}
 203
 204	viodbg(HS, "SEND NET ATTR ACK xmode[0x%x] atype[0x%x] "
 205	       "addr[%llx] ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] "
 206	       "mtu[%llu] (rmtu[%llu]) cflags[0x%04x] lso_max[%u]\n",
 207	       pkt->xfer_mode, pkt->addr_type,
 208	       (unsigned long long)pkt->addr,
 209	       pkt->ack_freq, pkt->plnk_updt, pkt->options,
 210	       (unsigned long long)pkt->mtu, port->rmtu, pkt->cflags,
 211	       pkt->ipv4_lso_maxlen);
 212
 213	pkt->tag.stype = VIO_SUBTYPE_ACK;
 214
 215	return vio_ldc_send(vio, pkt, sizeof(*pkt));
 216}
 217
 218static int handle_attr_ack(struct vio_driver_state *vio,
 219			   struct vio_net_attr_info *pkt)
 220{
 221	viodbg(HS, "GOT NET ATTR ACK\n");
 222
 223	return 0;
 224}
 225
 226static int handle_attr_nack(struct vio_driver_state *vio,
 227			    struct vio_net_attr_info *pkt)
 228{
 229	viodbg(HS, "GOT NET ATTR NACK\n");
 230
 231	return -ECONNRESET;
 232}
 233
 234int sunvnet_handle_attr_common(struct vio_driver_state *vio, void *arg)
 235{
 236	struct vio_net_attr_info *pkt = arg;
 237
 238	switch (pkt->tag.stype) {
 239	case VIO_SUBTYPE_INFO:
 240		return handle_attr_info(vio, pkt);
 241
 242	case VIO_SUBTYPE_ACK:
 243		return handle_attr_ack(vio, pkt);
 244
 245	case VIO_SUBTYPE_NACK:
 246		return handle_attr_nack(vio, pkt);
 247
 248	default:
 249		return -ECONNRESET;
 250	}
 251}
 252EXPORT_SYMBOL_GPL(sunvnet_handle_attr_common);
 253
 254void sunvnet_handshake_complete_common(struct vio_driver_state *vio)
 255{
 256	struct vio_dring_state *dr;
 257
 258	dr = &vio->drings[VIO_DRIVER_RX_RING];
 259	dr->rcv_nxt = 1;
 260	dr->snd_nxt = 1;
 261
 262	dr = &vio->drings[VIO_DRIVER_TX_RING];
 263	dr->rcv_nxt = 1;
 264	dr->snd_nxt = 1;
 265}
 266EXPORT_SYMBOL_GPL(sunvnet_handshake_complete_common);
 267
 268/* The hypervisor interface that implements copying to/from imported
 269 * memory from another domain requires that copies are done to 8-byte
 270 * aligned buffers, and that the lengths of such copies are also 8-byte
 271 * multiples.
 272 *
 273 * So we align skb->data to an 8-byte multiple and pad-out the data
 274 * area so we can round the copy length up to the next multiple of
 275 * 8 for the copy.
 276 *
 277 * The transmitter puts the actual start of the packet 6 bytes into
 278 * the buffer it sends over, so that the IP headers after the ethernet
 279 * header are aligned properly.  These 6 bytes are not in the descriptor
 280 * length, they are simply implied.  This offset is represented using
 281 * the VNET_PACKET_SKIP macro.
 282 */
 283static struct sk_buff *alloc_and_align_skb(struct net_device *dev,
 284					   unsigned int len)
 285{
 286	struct sk_buff *skb;
 287	unsigned long addr, off;
 288
 289	skb = netdev_alloc_skb(dev, len + VNET_PACKET_SKIP + 8 + 8);
 290	if (unlikely(!skb))
 291		return NULL;
 292
 293	addr = (unsigned long)skb->data;
 294	off = ((addr + 7UL) & ~7UL) - addr;
 295	if (off)
 296		skb_reserve(skb, off);
 297
 298	return skb;
 299}
 300
 301static inline void vnet_fullcsum(struct sk_buff *skb)
 302{
 303	struct iphdr *iph = ip_hdr(skb);
 304	int offset = skb_transport_offset(skb);
 305
 306	if (skb->protocol != htons(ETH_P_IP))
 307		return;
 308	if (iph->protocol != IPPROTO_TCP &&
 309	    iph->protocol != IPPROTO_UDP)
 310		return;
 311	skb->ip_summed = CHECKSUM_NONE;
 312	skb->csum_level = 1;
 313	skb->csum = 0;
 314	if (iph->protocol == IPPROTO_TCP) {
 315		struct tcphdr *ptcp = tcp_hdr(skb);
 316
 317		ptcp->check = 0;
 318		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
 319		ptcp->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
 320						skb->len - offset, IPPROTO_TCP,
 321						skb->csum);
 322	} else if (iph->protocol == IPPROTO_UDP) {
 323		struct udphdr *pudp = udp_hdr(skb);
 324
 325		pudp->check = 0;
 326		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
 327		pudp->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
 328						skb->len - offset, IPPROTO_UDP,
 329						skb->csum);
 330	}
 331}
 332
 333static int vnet_rx_one(struct vnet_port *port, struct vio_net_desc *desc)
 334{
 335	struct net_device *dev = VNET_PORT_TO_NET_DEVICE(port);
 336	unsigned int len = desc->size;
 337	unsigned int copy_len;
 338	struct sk_buff *skb;
 339	int maxlen;
 340	int err;
 341
 342	err = -EMSGSIZE;
 343	if (port->tso && port->tsolen > port->rmtu)
 344		maxlen = port->tsolen;
 345	else
 346		maxlen = port->rmtu;
 347	if (unlikely(len < ETH_ZLEN || len > maxlen)) {
 348		dev->stats.rx_length_errors++;
 349		goto out_dropped;
 350	}
 351
 352	skb = alloc_and_align_skb(dev, len);
 353	err = -ENOMEM;
 354	if (unlikely(!skb)) {
 355		dev->stats.rx_missed_errors++;
 356		goto out_dropped;
 357	}
 358
 359	copy_len = (len + VNET_PACKET_SKIP + 7U) & ~7U;
 360	skb_put(skb, copy_len);
 361	err = ldc_copy(port->vio.lp, LDC_COPY_IN,
 362		       skb->data, copy_len, 0,
 363		       desc->cookies, desc->ncookies);
 364	if (unlikely(err < 0)) {
 365		dev->stats.rx_frame_errors++;
 366		goto out_free_skb;
 367	}
 368
 369	skb_pull(skb, VNET_PACKET_SKIP);
 370	skb_trim(skb, len);
 371	skb->protocol = eth_type_trans(skb, dev);
 372
 373	if (vio_version_after_eq(&port->vio, 1, 8)) {
 374		struct vio_net_dext *dext = vio_net_ext(desc);
 375
 376		skb_reset_network_header(skb);
 377
 378		if (dext->flags & VNET_PKT_HCK_IPV4_HDRCKSUM) {
 379			if (skb->protocol == ETH_P_IP) {
 380				struct iphdr *iph = ip_hdr(skb);
 381
 382				iph->check = 0;
 383				ip_send_check(iph);
 384			}
 385		}
 386		if ((dext->flags & VNET_PKT_HCK_FULLCKSUM) &&
 387		    skb->ip_summed == CHECKSUM_NONE) {
 388			if (skb->protocol == htons(ETH_P_IP)) {
 389				struct iphdr *iph = ip_hdr(skb);
 390				int ihl = iph->ihl * 4;
 391
 392				skb_reset_transport_header(skb);
 393				skb_set_transport_header(skb, ihl);
 394				vnet_fullcsum(skb);
 395			}
 396		}
 397		if (dext->flags & VNET_PKT_HCK_IPV4_HDRCKSUM_OK) {
 398			skb->ip_summed = CHECKSUM_PARTIAL;
 399			skb->csum_level = 0;
 400			if (dext->flags & VNET_PKT_HCK_FULLCKSUM_OK)
 401				skb->csum_level = 1;
 402		}
 403	}
 404
 405	skb->ip_summed = port->switch_port ? CHECKSUM_NONE : CHECKSUM_PARTIAL;
 406
 407	dev->stats.rx_packets++;
 408	dev->stats.rx_bytes += len;
 409	napi_gro_receive(&port->napi, skb);
 410	return 0;
 411
 412out_free_skb:
 413	kfree_skb(skb);
 414
 415out_dropped:
 416	dev->stats.rx_dropped++;
 417	return err;
 418}
 419
 420static int vnet_send_ack(struct vnet_port *port, struct vio_dring_state *dr,
 421			 u32 start, u32 end, u8 vio_dring_state)
 422{
 423	struct vio_dring_data hdr = {
 424		.tag = {
 425			.type		= VIO_TYPE_DATA,
 426			.stype		= VIO_SUBTYPE_ACK,
 427			.stype_env	= VIO_DRING_DATA,
 428			.sid		= vio_send_sid(&port->vio),
 429		},
 430		.dring_ident		= dr->ident,
 431		.start_idx		= start,
 432		.end_idx		= end,
 433		.state			= vio_dring_state,
 434	};
 435	int err, delay;
 436	int retries = 0;
 437
 438	hdr.seq = dr->snd_nxt;
 439	delay = 1;
 440	do {
 441		err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 442		if (err > 0) {
 443			dr->snd_nxt++;
 444			break;
 445		}
 446		udelay(delay);
 447		if ((delay <<= 1) > 128)
 448			delay = 128;
 449		if (retries++ > VNET_MAX_RETRIES) {
 450			pr_info("ECONNRESET %x:%x:%x:%x:%x:%x\n",
 451				port->raddr[0], port->raddr[1],
 452				port->raddr[2], port->raddr[3],
 453				port->raddr[4], port->raddr[5]);
 454			break;
 455		}
 456	} while (err == -EAGAIN);
 457
 458	if (err <= 0 && vio_dring_state == VIO_DRING_STOPPED) {
 459		port->stop_rx_idx = end;
 460		port->stop_rx = true;
 461	} else {
 462		port->stop_rx_idx = 0;
 463		port->stop_rx = false;
 464	}
 465
 466	return err;
 467}
 468
 469static struct vio_net_desc *get_rx_desc(struct vnet_port *port,
 470					struct vio_dring_state *dr,
 471					u32 index)
 472{
 473	struct vio_net_desc *desc = port->vio.desc_buf;
 474	int err;
 475
 476	err = ldc_get_dring_entry(port->vio.lp, desc, dr->entry_size,
 477				  (index * dr->entry_size),
 478				  dr->cookies, dr->ncookies);
 479	if (err < 0)
 480		return ERR_PTR(err);
 481
 482	return desc;
 483}
 484
 485static int put_rx_desc(struct vnet_port *port,
 486		       struct vio_dring_state *dr,
 487		       struct vio_net_desc *desc,
 488		       u32 index)
 489{
 490	int err;
 491
 492	err = ldc_put_dring_entry(port->vio.lp, desc, dr->entry_size,
 493				  (index * dr->entry_size),
 494				  dr->cookies, dr->ncookies);
 495	if (err < 0)
 496		return err;
 497
 498	return 0;
 499}
 500
 501static int vnet_walk_rx_one(struct vnet_port *port,
 502			    struct vio_dring_state *dr,
 503			    u32 index, int *needs_ack)
 504{
 505	struct vio_net_desc *desc = get_rx_desc(port, dr, index);
 506	struct vio_driver_state *vio = &port->vio;
 507	int err;
 508
 509	BUG_ON(!desc);
 510	if (IS_ERR(desc))
 511		return PTR_ERR(desc);
 512
 513	if (desc->hdr.state != VIO_DESC_READY)
 514		return 1;
 515
 516	dma_rmb();
 517
 518	viodbg(DATA, "vio_walk_rx_one desc[%02x:%02x:%08x:%08x:%llx:%llx]\n",
 519	       desc->hdr.state, desc->hdr.ack,
 520	       desc->size, desc->ncookies,
 521	       desc->cookies[0].cookie_addr,
 522	       desc->cookies[0].cookie_size);
 523
 524	err = vnet_rx_one(port, desc);
 525	if (err == -ECONNRESET)
 526		return err;
 527	trace_vnet_rx_one(port->vio._local_sid, port->vio._peer_sid,
 528			  index, desc->hdr.ack);
 529	desc->hdr.state = VIO_DESC_DONE;
 530	err = put_rx_desc(port, dr, desc, index);
 531	if (err < 0)
 532		return err;
 533	*needs_ack = desc->hdr.ack;
 534	return 0;
 535}
 536
 537static int vnet_walk_rx(struct vnet_port *port, struct vio_dring_state *dr,
 538			u32 start, u32 end, int *npkts, int budget)
 539{
 540	struct vio_driver_state *vio = &port->vio;
 541	int ack_start = -1, ack_end = -1;
 542	bool send_ack = true;
 543
 544	end = (end == (u32)-1) ? vio_dring_prev(dr, start)
 545			       : vio_dring_next(dr, end);
 546
 547	viodbg(DATA, "vnet_walk_rx start[%08x] end[%08x]\n", start, end);
 548
 549	while (start != end) {
 550		int ack = 0, err = vnet_walk_rx_one(port, dr, start, &ack);
 551
 552		if (err == -ECONNRESET)
 553			return err;
 554		if (err != 0)
 555			break;
 556		(*npkts)++;
 557		if (ack_start == -1)
 558			ack_start = start;
 559		ack_end = start;
 560		start = vio_dring_next(dr, start);
 561		if (ack && start != end) {
 562			err = vnet_send_ack(port, dr, ack_start, ack_end,
 563					    VIO_DRING_ACTIVE);
 564			if (err == -ECONNRESET)
 565				return err;
 566			ack_start = -1;
 567		}
 568		if ((*npkts) >= budget) {
 569			send_ack = false;
 570			break;
 571		}
 572	}
 573	if (unlikely(ack_start == -1)) {
 574		ack_end = vio_dring_prev(dr, start);
 575		ack_start = ack_end;
 576	}
 577	if (send_ack) {
 578		port->napi_resume = false;
 579		trace_vnet_tx_send_stopped_ack(port->vio._local_sid,
 580					       port->vio._peer_sid,
 581					       ack_end, *npkts);
 582		return vnet_send_ack(port, dr, ack_start, ack_end,
 583				     VIO_DRING_STOPPED);
 584	} else  {
 585		trace_vnet_tx_defer_stopped_ack(port->vio._local_sid,
 586						port->vio._peer_sid,
 587						ack_end, *npkts);
 588		port->napi_resume = true;
 589		port->napi_stop_idx = ack_end;
 590		return 1;
 591	}
 592}
 593
 594static int vnet_rx(struct vnet_port *port, void *msgbuf, int *npkts,
 595		   int budget)
 596{
 597	struct vio_dring_data *pkt = msgbuf;
 598	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_RX_RING];
 599	struct vio_driver_state *vio = &port->vio;
 600
 601	viodbg(DATA, "vnet_rx stype_env[%04x] seq[%016llx] rcv_nxt[%016llx]\n",
 602	       pkt->tag.stype_env, pkt->seq, dr->rcv_nxt);
 603
 604	if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
 605		return 0;
 606	if (unlikely(pkt->seq != dr->rcv_nxt)) {
 607		pr_err("RX out of sequence seq[0x%llx] rcv_nxt[0x%llx]\n",
 608		       pkt->seq, dr->rcv_nxt);
 609		return 0;
 610	}
 611
 612	if (!port->napi_resume)
 613		dr->rcv_nxt++;
 614
 615	/* XXX Validate pkt->start_idx and pkt->end_idx XXX */
 616
 617	return vnet_walk_rx(port, dr, pkt->start_idx, pkt->end_idx,
 618			    npkts, budget);
 619}
 620
 621static int idx_is_pending(struct vio_dring_state *dr, u32 end)
 622{
 623	u32 idx = dr->cons;
 624	int found = 0;
 625
 626	while (idx != dr->prod) {
 627		if (idx == end) {
 628			found = 1;
 629			break;
 630		}
 631		idx = vio_dring_next(dr, idx);
 632	}
 633	return found;
 634}
 635
 636static int vnet_ack(struct vnet_port *port, void *msgbuf)
 637{
 638	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 639	struct vio_dring_data *pkt = msgbuf;
 640	struct net_device *dev;
 641	u32 end;
 642	struct vio_net_desc *desc;
 643	struct netdev_queue *txq;
 644
 645	if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
 646		return 0;
 647
 648	end = pkt->end_idx;
 649	dev = VNET_PORT_TO_NET_DEVICE(port);
 650	netif_tx_lock(dev);
 651	if (unlikely(!idx_is_pending(dr, end))) {
 652		netif_tx_unlock(dev);
 653		return 0;
 654	}
 655
 656	/* sync for race conditions with vnet_start_xmit() and tell xmit it
 657	 * is time to send a trigger.
 658	 */
 659	trace_vnet_rx_stopped_ack(port->vio._local_sid,
 660				  port->vio._peer_sid, end);
 661	dr->cons = vio_dring_next(dr, end);
 662	desc = vio_dring_entry(dr, dr->cons);
 663	if (desc->hdr.state == VIO_DESC_READY && !port->start_cons) {
 664		/* vnet_start_xmit() just populated this dring but missed
 665		 * sending the "start" LDC message to the consumer.
 666		 * Send a "start" trigger on its behalf.
 667		 */
 668		if (__vnet_tx_trigger(port, dr->cons) > 0)
 669			port->start_cons = false;
 670		else
 671			port->start_cons = true;
 672	} else {
 673		port->start_cons = true;
 674	}
 675	netif_tx_unlock(dev);
 676
 677	txq = netdev_get_tx_queue(dev, port->q_index);
 678	if (unlikely(netif_tx_queue_stopped(txq) &&
 679		     vnet_tx_dring_avail(dr) >= VNET_TX_WAKEUP_THRESH(dr)))
 680		return 1;
 681
 682	return 0;
 683}
 684
 685static int vnet_nack(struct vnet_port *port, void *msgbuf)
 686{
 687	/* XXX just reset or similar XXX */
 688	return 0;
 689}
 690
 691static int handle_mcast(struct vnet_port *port, void *msgbuf)
 692{
 693	struct vio_net_mcast_info *pkt = msgbuf;
 694	struct net_device *dev = VNET_PORT_TO_NET_DEVICE(port);
 695
 696	if (pkt->tag.stype != VIO_SUBTYPE_ACK)
 697		pr_err("%s: Got unexpected MCAST reply [%02x:%02x:%04x:%08x]\n",
 698		       dev->name,
 699		       pkt->tag.type,
 700		       pkt->tag.stype,
 701		       pkt->tag.stype_env,
 702		       pkt->tag.sid);
 703
 704	return 0;
 705}
 706
 707/* If the queue is stopped, wake it up so that we'll
 708 * send out another START message at the next TX.
 709 */
 710static void maybe_tx_wakeup(struct vnet_port *port)
 711{
 712	struct netdev_queue *txq;
 713
 714	txq = netdev_get_tx_queue(VNET_PORT_TO_NET_DEVICE(port),
 715				  port->q_index);
 716	__netif_tx_lock(txq, smp_processor_id());
 717	if (likely(netif_tx_queue_stopped(txq))) {
 718		struct vio_dring_state *dr;
 719
 720		dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 721		netif_tx_wake_queue(txq);
 722	}
 723	__netif_tx_unlock(txq);
 724}
 725
 726bool sunvnet_port_is_up_common(struct vnet_port *vnet)
 727{
 728	struct vio_driver_state *vio = &vnet->vio;
 729
 730	return !!(vio->hs_state & VIO_HS_COMPLETE);
 731}
 732EXPORT_SYMBOL_GPL(sunvnet_port_is_up_common);
 733
 734static int vnet_event_napi(struct vnet_port *port, int budget)
 735{
 736	struct net_device *dev = VNET_PORT_TO_NET_DEVICE(port);
 737	struct vio_driver_state *vio = &port->vio;
 738	int tx_wakeup, err;
 739	int npkts = 0;
 740	int event = (port->rx_event & LDC_EVENT_RESET);
 741
 742ldc_ctrl:
 743	if (unlikely(event == LDC_EVENT_RESET ||
 744		     event == LDC_EVENT_UP)) {
 745		vio_link_state_change(vio, event);
 746
 747		if (event == LDC_EVENT_RESET) {
 748			vnet_port_reset(port);
 749			vio_port_up(vio);
 750
 751			/* If the device is running but its tx queue was
 752			 * stopped (due to flow control), restart it.
 753			 * This is necessary since vnet_port_reset()
 754			 * clears the tx drings and thus we may never get
 755			 * back a VIO_TYPE_DATA ACK packet - which is
 756			 * the normal mechanism to restart the tx queue.
 757			 */
 758			if (netif_running(dev))
 759				maybe_tx_wakeup(port);
 760		}
 761		port->rx_event = 0;
 762		return 0;
 763	}
 764	/* We may have multiple LDC events in rx_event. Unroll send_events() */
 765	event = (port->rx_event & LDC_EVENT_UP);
 766	port->rx_event &= ~(LDC_EVENT_RESET | LDC_EVENT_UP);
 767	if (event == LDC_EVENT_UP)
 768		goto ldc_ctrl;
 769	event = port->rx_event;
 770	if (!(event & LDC_EVENT_DATA_READY))
 771		return 0;
 772
 773	/* we dont expect any other bits than RESET, UP, DATA_READY */
 774	BUG_ON(event != LDC_EVENT_DATA_READY);
 775
 776	err = 0;
 777	tx_wakeup = 0;
 778	while (1) {
 779		union {
 780			struct vio_msg_tag tag;
 781			u64 raw[8];
 782		} msgbuf;
 783
 784		if (port->napi_resume) {
 785			struct vio_dring_data *pkt =
 786				(struct vio_dring_data *)&msgbuf;
 787			struct vio_dring_state *dr =
 788				&port->vio.drings[VIO_DRIVER_RX_RING];
 789
 790			pkt->tag.type = VIO_TYPE_DATA;
 791			pkt->tag.stype = VIO_SUBTYPE_INFO;
 792			pkt->tag.stype_env = VIO_DRING_DATA;
 793			pkt->seq = dr->rcv_nxt;
 794			pkt->start_idx = vio_dring_next(dr,
 795							port->napi_stop_idx);
 796			pkt->end_idx = -1;
 797			goto napi_resume;
 798		}
 799		err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
 800		if (unlikely(err < 0)) {
 801			if (err == -ECONNRESET)
 802				vio_conn_reset(vio);
 803			break;
 804		}
 805		if (err == 0)
 806			break;
 807		viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
 808		       msgbuf.tag.type,
 809		       msgbuf.tag.stype,
 810		       msgbuf.tag.stype_env,
 811		       msgbuf.tag.sid);
 812		err = vio_validate_sid(vio, &msgbuf.tag);
 813		if (err < 0)
 814			break;
 815napi_resume:
 816		if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
 817			if (msgbuf.tag.stype == VIO_SUBTYPE_INFO) {
 818				if (!sunvnet_port_is_up_common(port)) {
 819					/* failures like handshake_failure()
 820					 * may have cleaned up dring, but
 821					 * NAPI polling may bring us here.
 822					 */
 823					err = -ECONNRESET;
 824					break;
 825				}
 826				err = vnet_rx(port, &msgbuf, &npkts, budget);
 827				if (npkts >= budget)
 828					break;
 829				if (npkts == 0)
 830					break;
 831			} else if (msgbuf.tag.stype == VIO_SUBTYPE_ACK) {
 832				err = vnet_ack(port, &msgbuf);
 833				if (err > 0)
 834					tx_wakeup |= err;
 835			} else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK) {
 836				err = vnet_nack(port, &msgbuf);
 837			}
 838		} else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
 839			if (msgbuf.tag.stype_env == VNET_MCAST_INFO)
 840				err = handle_mcast(port, &msgbuf);
 841			else
 842				err = vio_control_pkt_engine(vio, &msgbuf);
 843			if (err)
 844				break;
 845		} else {
 846			err = vnet_handle_unknown(port, &msgbuf);
 847		}
 848		if (err == -ECONNRESET)
 849			break;
 850	}
 851	if (unlikely(tx_wakeup && err != -ECONNRESET))
 852		maybe_tx_wakeup(port);
 853	return npkts;
 854}
 855
 856int sunvnet_poll_common(struct napi_struct *napi, int budget)
 857{
 858	struct vnet_port *port = container_of(napi, struct vnet_port, napi);
 859	struct vio_driver_state *vio = &port->vio;
 860	int processed = vnet_event_napi(port, budget);
 861
 862	if (processed < budget) {
 863		napi_complete(napi);
 864		port->rx_event &= ~LDC_EVENT_DATA_READY;
 865		vio_set_intr(vio->vdev->rx_ino, HV_INTR_ENABLED);
 866	}
 867	return processed;
 868}
 869EXPORT_SYMBOL_GPL(sunvnet_poll_common);
 870
 871void sunvnet_event_common(void *arg, int event)
 872{
 873	struct vnet_port *port = arg;
 874	struct vio_driver_state *vio = &port->vio;
 875
 876	port->rx_event |= event;
 877	vio_set_intr(vio->vdev->rx_ino, HV_INTR_DISABLED);
 878	napi_schedule(&port->napi);
 879}
 880EXPORT_SYMBOL_GPL(sunvnet_event_common);
 881
 882static int __vnet_tx_trigger(struct vnet_port *port, u32 start)
 883{
 884	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 885	struct vio_dring_data hdr = {
 886		.tag = {
 887			.type		= VIO_TYPE_DATA,
 888			.stype		= VIO_SUBTYPE_INFO,
 889			.stype_env	= VIO_DRING_DATA,
 890			.sid		= vio_send_sid(&port->vio),
 891		},
 892		.dring_ident		= dr->ident,
 893		.start_idx		= start,
 894		.end_idx		= (u32)-1,
 895	};
 896	int err, delay;
 897	int retries = 0;
 898
 899	if (port->stop_rx) {
 900		trace_vnet_tx_pending_stopped_ack(port->vio._local_sid,
 901						  port->vio._peer_sid,
 902						  port->stop_rx_idx, -1);
 903		err = vnet_send_ack(port,
 904				    &port->vio.drings[VIO_DRIVER_RX_RING],
 905				    port->stop_rx_idx, -1,
 906				    VIO_DRING_STOPPED);
 907		if (err <= 0)
 908			return err;
 909	}
 910
 911	hdr.seq = dr->snd_nxt;
 912	delay = 1;
 913	do {
 914		err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 915		if (err > 0) {
 916			dr->snd_nxt++;
 917			break;
 918		}
 919		udelay(delay);
 920		if ((delay <<= 1) > 128)
 921			delay = 128;
 922		if (retries++ > VNET_MAX_RETRIES)
 923			break;
 924	} while (err == -EAGAIN);
 925	trace_vnet_tx_trigger(port->vio._local_sid,
 926			      port->vio._peer_sid, start, err);
 927
 928	return err;
 929}
 930
 931static struct sk_buff *vnet_clean_tx_ring(struct vnet_port *port,
 932					  unsigned *pending)
 933{
 934	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 935	struct sk_buff *skb = NULL;
 936	int i, txi;
 937
 938	*pending = 0;
 939
 940	txi = dr->prod;
 941	for (i = 0; i < VNET_TX_RING_SIZE; ++i) {
 942		struct vio_net_desc *d;
 943
 944		--txi;
 945		if (txi < 0)
 946			txi = VNET_TX_RING_SIZE - 1;
 947
 948		d = vio_dring_entry(dr, txi);
 949
 950		if (d->hdr.state == VIO_DESC_READY) {
 951			(*pending)++;
 952			continue;
 953		}
 954		if (port->tx_bufs[txi].skb) {
 955			if (d->hdr.state != VIO_DESC_DONE)
 956				pr_notice("invalid ring buffer state %d\n",
 957					  d->hdr.state);
 958			BUG_ON(port->tx_bufs[txi].skb->next);
 959
 960			port->tx_bufs[txi].skb->next = skb;
 961			skb = port->tx_bufs[txi].skb;
 962			port->tx_bufs[txi].skb = NULL;
 963
 964			ldc_unmap(port->vio.lp,
 965				  port->tx_bufs[txi].cookies,
 966				  port->tx_bufs[txi].ncookies);
 967		} else if (d->hdr.state == VIO_DESC_FREE) {
 968			break;
 969		}
 970		d->hdr.state = VIO_DESC_FREE;
 971	}
 972	return skb;
 973}
 974
 975static inline void vnet_free_skbs(struct sk_buff *skb)
 976{
 977	struct sk_buff *next;
 978
 979	while (skb) {
 980		next = skb->next;
 981		skb->next = NULL;
 982		dev_kfree_skb(skb);
 983		skb = next;
 984	}
 985}
 986
 987void sunvnet_clean_timer_expire_common(unsigned long port0)
 988{
 989	struct vnet_port *port = (struct vnet_port *)port0;
 990	struct sk_buff *freeskbs;
 991	unsigned pending;
 992
 993	netif_tx_lock(VNET_PORT_TO_NET_DEVICE(port));
 994	freeskbs = vnet_clean_tx_ring(port, &pending);
 995	netif_tx_unlock(VNET_PORT_TO_NET_DEVICE(port));
 996
 997	vnet_free_skbs(freeskbs);
 998
 999	if (pending)
1000		(void)mod_timer(&port->clean_timer,
1001				jiffies + VNET_CLEAN_TIMEOUT);
1002	 else
1003		del_timer(&port->clean_timer);
1004}
1005EXPORT_SYMBOL_GPL(sunvnet_clean_timer_expire_common);
1006
1007static inline int vnet_skb_map(struct ldc_channel *lp, struct sk_buff *skb,
1008			       struct ldc_trans_cookie *cookies, int ncookies,
1009			       unsigned int map_perm)
1010{
1011	int i, nc, err, blen;
1012
1013	/* header */
1014	blen = skb_headlen(skb);
1015	if (blen < ETH_ZLEN)
1016		blen = ETH_ZLEN;
1017	blen += VNET_PACKET_SKIP;
1018	blen += 8 - (blen & 7);
1019
1020	err = ldc_map_single(lp, skb->data - VNET_PACKET_SKIP, blen, cookies,
1021			     ncookies, map_perm);
1022	if (err < 0)
1023		return err;
1024	nc = err;
1025
1026	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1027		skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1028		u8 *vaddr;
1029
1030		if (nc < ncookies) {
1031			vaddr = kmap_atomic(skb_frag_page(f));
1032			blen = skb_frag_size(f);
1033			blen += 8 - (blen & 7);
1034			err = ldc_map_single(lp, vaddr + f->page_offset,
1035					     blen, cookies + nc, ncookies - nc,
1036					     map_perm);
1037			kunmap_atomic(vaddr);
1038		} else {
1039			err = -EMSGSIZE;
1040		}
1041
1042		if (err < 0) {
1043			ldc_unmap(lp, cookies, nc);
1044			return err;
1045		}
1046		nc += err;
1047	}
1048	return nc;
1049}
1050
1051static inline struct sk_buff *vnet_skb_shape(struct sk_buff *skb, int ncookies)
1052{
1053	struct sk_buff *nskb;
1054	int i, len, pad, docopy;
1055
1056	len = skb->len;
1057	pad = 0;
1058	if (len < ETH_ZLEN) {
1059		pad += ETH_ZLEN - skb->len;
1060		len += pad;
1061	}
1062	len += VNET_PACKET_SKIP;
1063	pad += 8 - (len & 7);
1064
1065	/* make sure we have enough cookies and alignment in every frag */
1066	docopy = skb_shinfo(skb)->nr_frags >= ncookies;
1067	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1068		skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1069
1070		docopy |= f->page_offset & 7;
1071	}
1072	if (((unsigned long)skb->data & 7) != VNET_PACKET_SKIP ||
1073	    skb_tailroom(skb) < pad ||
1074	    skb_headroom(skb) < VNET_PACKET_SKIP || docopy) {
1075		int start = 0, offset;
1076		__wsum csum;
1077
1078		len = skb->len > ETH_ZLEN ? skb->len : ETH_ZLEN;
1079		nskb = alloc_and_align_skb(skb->dev, len);
1080		if (!nskb) {
1081			dev_kfree_skb(skb);
1082			return NULL;
1083		}
1084		skb_reserve(nskb, VNET_PACKET_SKIP);
1085
1086		nskb->protocol = skb->protocol;
1087		offset = skb_mac_header(skb) - skb->data;
1088		skb_set_mac_header(nskb, offset);
1089		offset = skb_network_header(skb) - skb->data;
1090		skb_set_network_header(nskb, offset);
1091		offset = skb_transport_header(skb) - skb->data;
1092		skb_set_transport_header(nskb, offset);
1093
1094		offset = 0;
1095		nskb->csum_offset = skb->csum_offset;
1096		nskb->ip_summed = skb->ip_summed;
1097
1098		if (skb->ip_summed == CHECKSUM_PARTIAL)
1099			start = skb_checksum_start_offset(skb);
1100		if (start) {
1101			struct iphdr *iph = ip_hdr(nskb);
1102			int offset = start + nskb->csum_offset;
1103
1104			if (skb_copy_bits(skb, 0, nskb->data, start)) {
1105				dev_kfree_skb(nskb);
1106				dev_kfree_skb(skb);
1107				return NULL;
1108			}
1109			*(__sum16 *)(skb->data + offset) = 0;
1110			csum = skb_copy_and_csum_bits(skb, start,
1111						      nskb->data + start,
1112						      skb->len - start, 0);
1113			if (iph->protocol == IPPROTO_TCP ||
1114			    iph->protocol == IPPROTO_UDP) {
1115				csum = csum_tcpudp_magic(iph->saddr, iph->daddr,
1116							 skb->len - start,
1117							 iph->protocol, csum);
1118			}
1119			*(__sum16 *)(nskb->data + offset) = csum;
1120
1121			nskb->ip_summed = CHECKSUM_NONE;
1122		} else if (skb_copy_bits(skb, 0, nskb->data, skb->len)) {
1123			dev_kfree_skb(nskb);
1124			dev_kfree_skb(skb);
1125			return NULL;
1126		}
1127		(void)skb_put(nskb, skb->len);
1128		if (skb_is_gso(skb)) {
1129			skb_shinfo(nskb)->gso_size = skb_shinfo(skb)->gso_size;
1130			skb_shinfo(nskb)->gso_type = skb_shinfo(skb)->gso_type;
1131		}
1132		nskb->queue_mapping = skb->queue_mapping;
1133		dev_kfree_skb(skb);
1134		skb = nskb;
1135	}
1136	return skb;
1137}
1138
1139static int vnet_handle_offloads(struct vnet_port *port, struct sk_buff *skb,
1140				struct vnet_port *(*vnet_tx_port)
1141				(struct sk_buff *, struct net_device *))
1142{
1143	struct net_device *dev = VNET_PORT_TO_NET_DEVICE(port);
1144	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1145	struct sk_buff *segs;
1146	int maclen, datalen;
1147	int status;
1148	int gso_size, gso_type, gso_segs;
1149	int hlen = skb_transport_header(skb) - skb_mac_header(skb);
1150	int proto = IPPROTO_IP;
1151
1152	if (skb->protocol == htons(ETH_P_IP))
1153		proto = ip_hdr(skb)->protocol;
1154	else if (skb->protocol == htons(ETH_P_IPV6))
1155		proto = ipv6_hdr(skb)->nexthdr;
1156
1157	if (proto == IPPROTO_TCP) {
1158		hlen += tcp_hdr(skb)->doff * 4;
1159	} else if (proto == IPPROTO_UDP) {
1160		hlen += sizeof(struct udphdr);
1161	} else {
1162		pr_err("vnet_handle_offloads GSO with unknown transport "
1163		       "protocol %d tproto %d\n", skb->protocol, proto);
1164		hlen = 128; /* XXX */
1165	}
1166	datalen = port->tsolen - hlen;
1167
1168	gso_size = skb_shinfo(skb)->gso_size;
1169	gso_type = skb_shinfo(skb)->gso_type;
1170	gso_segs = skb_shinfo(skb)->gso_segs;
1171
1172	if (port->tso && gso_size < datalen)
1173		gso_segs = DIV_ROUND_UP(skb->len - hlen, datalen);
1174
1175	if (unlikely(vnet_tx_dring_avail(dr) < gso_segs)) {
1176		struct netdev_queue *txq;
1177
1178		txq  = netdev_get_tx_queue(dev, port->q_index);
1179		netif_tx_stop_queue(txq);
1180		if (vnet_tx_dring_avail(dr) < skb_shinfo(skb)->gso_segs)
1181			return NETDEV_TX_BUSY;
1182		netif_tx_wake_queue(txq);
1183	}
1184
1185	maclen = skb_network_header(skb) - skb_mac_header(skb);
1186	skb_pull(skb, maclen);
1187
1188	if (port->tso && gso_size < datalen) {
1189		if (skb_unclone(skb, GFP_ATOMIC))
1190			goto out_dropped;
1191
1192		/* segment to TSO size */
1193		skb_shinfo(skb)->gso_size = datalen;
1194		skb_shinfo(skb)->gso_segs = gso_segs;
1195	}
1196	segs = skb_gso_segment(skb, dev->features & ~NETIF_F_TSO);
1197	if (IS_ERR(segs))
1198		goto out_dropped;
1199
1200	skb_push(skb, maclen);
1201	skb_reset_mac_header(skb);
1202
1203	status = 0;
1204	while (segs) {
1205		struct sk_buff *curr = segs;
1206
1207		segs = segs->next;
1208		curr->next = NULL;
1209		if (port->tso && curr->len > dev->mtu) {
1210			skb_shinfo(curr)->gso_size = gso_size;
1211			skb_shinfo(curr)->gso_type = gso_type;
1212			skb_shinfo(curr)->gso_segs =
1213				DIV_ROUND_UP(curr->len - hlen, gso_size);
1214		} else {
1215			skb_shinfo(curr)->gso_size = 0;
1216		}
1217
1218		skb_push(curr, maclen);
1219		skb_reset_mac_header(curr);
1220		memcpy(skb_mac_header(curr), skb_mac_header(skb),
1221		       maclen);
1222		curr->csum_start = skb_transport_header(curr) - curr->head;
1223		if (ip_hdr(curr)->protocol == IPPROTO_TCP)
1224			curr->csum_offset = offsetof(struct tcphdr, check);
1225		else if (ip_hdr(curr)->protocol == IPPROTO_UDP)
1226			curr->csum_offset = offsetof(struct udphdr, check);
1227
1228		if (!(status & NETDEV_TX_MASK))
1229			status = sunvnet_start_xmit_common(curr, dev,
1230							   vnet_tx_port);
1231		if (status & NETDEV_TX_MASK)
1232			dev_kfree_skb_any(curr);
1233	}
1234
1235	if (!(status & NETDEV_TX_MASK))
1236		dev_kfree_skb_any(skb);
1237	return status;
1238out_dropped:
1239	dev->stats.tx_dropped++;
1240	dev_kfree_skb_any(skb);
1241	return NETDEV_TX_OK;
1242}
1243
1244int sunvnet_start_xmit_common(struct sk_buff *skb, struct net_device *dev,
1245			      struct vnet_port *(*vnet_tx_port)
1246			      (struct sk_buff *, struct net_device *))
1247{
1248	struct vnet_port *port = NULL;
1249	struct vio_dring_state *dr;
1250	struct vio_net_desc *d;
1251	unsigned int len;
1252	struct sk_buff *freeskbs = NULL;
1253	int i, err, txi;
1254	unsigned pending = 0;
1255	struct netdev_queue *txq;
1256
1257	rcu_read_lock();
1258	port = vnet_tx_port(skb, dev);
1259	if (unlikely(!port)) {
1260		rcu_read_unlock();
1261		goto out_dropped;
1262	}
1263
1264	if (skb_is_gso(skb) && skb->len > port->tsolen) {
1265		err = vnet_handle_offloads(port, skb, vnet_tx_port);
1266		rcu_read_unlock();
1267		return err;
1268	}
1269
1270	if (!skb_is_gso(skb) && skb->len > port->rmtu) {
1271		unsigned long localmtu = port->rmtu - ETH_HLEN;
1272
1273		if (vio_version_after_eq(&port->vio, 1, 3))
1274			localmtu -= VLAN_HLEN;
1275
1276		if (skb->protocol == htons(ETH_P_IP)) {
1277			struct flowi4 fl4;
1278			struct rtable *rt = NULL;
1279
1280			memset(&fl4, 0, sizeof(fl4));
1281			fl4.flowi4_oif = dev->ifindex;
1282			fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);
1283			fl4.daddr = ip_hdr(skb)->daddr;
1284			fl4.saddr = ip_hdr(skb)->saddr;
1285
1286			rt = ip_route_output_key(dev_net(dev), &fl4);
1287			rcu_read_unlock();
1288			if (!IS_ERR(rt)) {
1289				skb_dst_set(skb, &rt->dst);
1290				icmp_send(skb, ICMP_DEST_UNREACH,
1291					  ICMP_FRAG_NEEDED,
1292					  htonl(localmtu));
1293			}
1294		}
1295#if IS_ENABLED(CONFIG_IPV6)
1296		else if (skb->protocol == htons(ETH_P_IPV6))
1297			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, localmtu);
1298#endif
1299		goto out_dropped;
1300	}
1301
1302	skb = vnet_skb_shape(skb, 2);
1303
1304	if (unlikely(!skb))
1305		goto out_dropped;
1306
1307	if (skb->ip_summed == CHECKSUM_PARTIAL)
1308		vnet_fullcsum(skb);
1309
1310	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1311	i = skb_get_queue_mapping(skb);
1312	txq = netdev_get_tx_queue(dev, i);
1313	if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
1314		if (!netif_tx_queue_stopped(txq)) {
1315			netif_tx_stop_queue(txq);
1316
1317			/* This is a hard error, log it. */
1318			netdev_err(dev, "BUG! Tx Ring full when queue awake!\n");
1319			dev->stats.tx_errors++;
1320		}
1321		rcu_read_unlock();
1322		return NETDEV_TX_BUSY;
1323	}
1324
1325	d = vio_dring_cur(dr);
1326
1327	txi = dr->prod;
1328
1329	freeskbs = vnet_clean_tx_ring(port, &pending);
1330
1331	BUG_ON(port->tx_bufs[txi].skb);
1332
1333	len = skb->len;
1334	if (len < ETH_ZLEN)
1335		len = ETH_ZLEN;
1336
1337	err = vnet_skb_map(port->vio.lp, skb, port->tx_bufs[txi].cookies, 2,
1338			   (LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_RW));
1339	if (err < 0) {
1340		netdev_info(dev, "tx buffer map error %d\n", err);
1341		goto out_dropped;
1342	}
1343
1344	port->tx_bufs[txi].skb = skb;
1345	skb = NULL;
1346	port->tx_bufs[txi].ncookies = err;
1347
1348	/* We don't rely on the ACKs to free the skb in vnet_start_xmit(),
1349	 * thus it is safe to not set VIO_ACK_ENABLE for each transmission:
1350	 * the protocol itself does not require it as long as the peer
1351	 * sends a VIO_SUBTYPE_ACK for VIO_DRING_STOPPED.
1352	 *
1353	 * An ACK for every packet in the ring is expensive as the
1354	 * sending of LDC messages is slow and affects performance.
1355	 */
1356	d->hdr.ack = VIO_ACK_DISABLE;
1357	d->size = len;
1358	d->ncookies = port->tx_bufs[txi].ncookies;
1359	for (i = 0; i < d->ncookies; i++)
1360		d->cookies[i] = port->tx_bufs[txi].cookies[i];
1361	if (vio_version_after_eq(&port->vio, 1, 7)) {
1362		struct vio_net_dext *dext = vio_net_ext(d);
1363
1364		memset(dext, 0, sizeof(*dext));
1365		if (skb_is_gso(port->tx_bufs[txi].skb)) {
1366			dext->ipv4_lso_mss = skb_shinfo(port->tx_bufs[txi].skb)
1367					     ->gso_size;
1368			dext->flags |= VNET_PKT_IPV4_LSO;
1369		}
1370		if (vio_version_after_eq(&port->vio, 1, 8) &&
1371		    !port->switch_port) {
1372			dext->flags |= VNET_PKT_HCK_IPV4_HDRCKSUM_OK;
1373			dext->flags |= VNET_PKT_HCK_FULLCKSUM_OK;
1374		}
1375	}
1376
1377	/* This has to be a non-SMP write barrier because we are writing
1378	 * to memory which is shared with the peer LDOM.
1379	 */
1380	dma_wmb();
1381
1382	d->hdr.state = VIO_DESC_READY;
1383
1384	/* Exactly one ldc "start" trigger (for dr->cons) needs to be sent
1385	 * to notify the consumer that some descriptors are READY.
1386	 * After that "start" trigger, no additional triggers are needed until
1387	 * a DRING_STOPPED is received from the consumer. The dr->cons field
1388	 * (set up by vnet_ack()) has the value of the next dring index
1389	 * that has not yet been ack-ed. We send a "start" trigger here
1390	 * if, and only if, start_cons is true (reset it afterward). Conversely,
1391	 * vnet_ack() should check if the dring corresponding to cons
1392	 * is marked READY, but start_cons was false.
1393	 * If so, vnet_ack() should send out the missed "start" trigger.
1394	 *
1395	 * Note that the dma_wmb() above makes sure the cookies et al. are
1396	 * not globally visible before the VIO_DESC_READY, and that the
1397	 * stores are ordered correctly by the compiler. The consumer will
1398	 * not proceed until the VIO_DESC_READY is visible assuring that
1399	 * the consumer does not observe anything related to descriptors
1400	 * out of order. The HV trap from the LDC start trigger is the
1401	 * producer to consumer announcement that work is available to the
1402	 * consumer
1403	 */
1404	if (!port->start_cons) { /* previous trigger suffices */
1405		trace_vnet_skip_tx_trigger(port->vio._local_sid,
1406					   port->vio._peer_sid, dr->cons);
1407		goto ldc_start_done;
1408	}
1409
1410	err = __vnet_tx_trigger(port, dr->cons);
1411	if (unlikely(err < 0)) {
1412		netdev_info(dev, "TX trigger error %d\n", err);
1413		d->hdr.state = VIO_DESC_FREE;
1414		skb = port->tx_bufs[txi].skb;
1415		port->tx_bufs[txi].skb = NULL;
1416		dev->stats.tx_carrier_errors++;
1417		goto out_dropped;
1418	}
1419
1420ldc_start_done:
1421	port->start_cons = false;
1422
1423	dev->stats.tx_packets++;
1424	dev->stats.tx_bytes += port->tx_bufs[txi].skb->len;
1425
1426	dr->prod = (dr->prod + 1) & (VNET_TX_RING_SIZE - 1);
1427	if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
1428		netif_tx_stop_queue(txq);
1429		if (vnet_tx_dring_avail(dr) > VNET_TX_WAKEUP_THRESH(dr))
1430			netif_tx_wake_queue(txq);
1431	}
1432
1433	(void)mod_timer(&port->clean_timer, jiffies + VNET_CLEAN_TIMEOUT);
1434	rcu_read_unlock();
1435
1436	vnet_free_skbs(freeskbs);
1437
1438	return NETDEV_TX_OK;
1439
1440out_dropped:
1441	if (pending)
1442		(void)mod_timer(&port->clean_timer,
1443				jiffies + VNET_CLEAN_TIMEOUT);
1444	else if (port)
1445		del_timer(&port->clean_timer);
1446	if (port)
1447		rcu_read_unlock();
1448	if (skb)
1449		dev_kfree_skb(skb);
1450	vnet_free_skbs(freeskbs);
1451	dev->stats.tx_dropped++;
1452	return NETDEV_TX_OK;
1453}
1454EXPORT_SYMBOL_GPL(sunvnet_start_xmit_common);
1455
1456void sunvnet_tx_timeout_common(struct net_device *dev)
1457{
1458	/* XXX Implement me XXX */
1459}
1460EXPORT_SYMBOL_GPL(sunvnet_tx_timeout_common);
1461
1462int sunvnet_open_common(struct net_device *dev)
1463{
1464	netif_carrier_on(dev);
1465	netif_tx_start_all_queues(dev);
1466
1467	return 0;
1468}
1469EXPORT_SYMBOL_GPL(sunvnet_open_common);
1470
1471int sunvnet_close_common(struct net_device *dev)
1472{
1473	netif_tx_stop_all_queues(dev);
1474	netif_carrier_off(dev);
1475
1476	return 0;
1477}
1478EXPORT_SYMBOL_GPL(sunvnet_close_common);
1479
1480static struct vnet_mcast_entry *__vnet_mc_find(struct vnet *vp, u8 *addr)
1481{
1482	struct vnet_mcast_entry *m;
1483
1484	for (m = vp->mcast_list; m; m = m->next) {
1485		if (ether_addr_equal(m->addr, addr))
1486			return m;
1487	}
1488	return NULL;
1489}
1490
1491static void __update_mc_list(struct vnet *vp, struct net_device *dev)
1492{
1493	struct netdev_hw_addr *ha;
1494
1495	netdev_for_each_mc_addr(ha, dev) {
1496		struct vnet_mcast_entry *m;
1497
1498		m = __vnet_mc_find(vp, ha->addr);
1499		if (m) {
1500			m->hit = 1;
1501			continue;
1502		}
1503
1504		if (!m) {
1505			m = kzalloc(sizeof(*m), GFP_ATOMIC);
1506			if (!m)
1507				continue;
1508			memcpy(m->addr, ha->addr, ETH_ALEN);
1509			m->hit = 1;
1510
1511			m->next = vp->mcast_list;
1512			vp->mcast_list = m;
1513		}
1514	}
1515}
1516
1517static void __send_mc_list(struct vnet *vp, struct vnet_port *port)
1518{
1519	struct vio_net_mcast_info info;
1520	struct vnet_mcast_entry *m, **pp;
1521	int n_addrs;
1522
1523	memset(&info, 0, sizeof(info));
1524
1525	info.tag.type = VIO_TYPE_CTRL;
1526	info.tag.stype = VIO_SUBTYPE_INFO;
1527	info.tag.stype_env = VNET_MCAST_INFO;
1528	info.tag.sid = vio_send_sid(&port->vio);
1529	info.set = 1;
1530
1531	n_addrs = 0;
1532	for (m = vp->mcast_list; m; m = m->next) {
1533		if (m->sent)
1534			continue;
1535		m->sent = 1;
1536		memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
1537		       m->addr, ETH_ALEN);
1538		if (++n_addrs == VNET_NUM_MCAST) {
1539			info.count = n_addrs;
1540
1541			(void)vio_ldc_send(&port->vio, &info,
1542					   sizeof(info));
1543			n_addrs = 0;
1544		}
1545	}
1546	if (n_addrs) {
1547		info.count = n_addrs;
1548		(void)vio_ldc_send(&port->vio, &info, sizeof(info));
1549	}
1550
1551	info.set = 0;
1552
1553	n_addrs = 0;
1554	pp = &vp->mcast_list;
1555	while ((m = *pp) != NULL) {
1556		if (m->hit) {
1557			m->hit = 0;
1558			pp = &m->next;
1559			continue;
1560		}
1561
1562		memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
1563		       m->addr, ETH_ALEN);
1564		if (++n_addrs == VNET_NUM_MCAST) {
1565			info.count = n_addrs;
1566			(void)vio_ldc_send(&port->vio, &info,
1567					   sizeof(info));
1568			n_addrs = 0;
1569		}
1570
1571		*pp = m->next;
1572		kfree(m);
1573	}
1574	if (n_addrs) {
1575		info.count = n_addrs;
1576		(void)vio_ldc_send(&port->vio, &info, sizeof(info));
1577	}
1578}
1579
1580void sunvnet_set_rx_mode_common(struct net_device *dev, struct vnet *vp)
1581{
1582	struct vnet_port *port;
1583
1584	rcu_read_lock();
1585	list_for_each_entry_rcu(port, &vp->port_list, list) {
1586		if (port->switch_port) {
1587			__update_mc_list(vp, dev);
1588			__send_mc_list(vp, port);
1589			break;
1590		}
1591	}
1592	rcu_read_unlock();
1593}
1594EXPORT_SYMBOL_GPL(sunvnet_set_rx_mode_common);
1595
1596int sunvnet_set_mac_addr_common(struct net_device *dev, void *p)
1597{
1598	return -EINVAL;
1599}
1600EXPORT_SYMBOL_GPL(sunvnet_set_mac_addr_common);
1601
1602void sunvnet_port_free_tx_bufs_common(struct vnet_port *port)
1603{
1604	struct vio_dring_state *dr;
1605	int i;
1606
1607	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1608
1609	if (!dr->base)
1610		return;
1611
1612	for (i = 0; i < VNET_TX_RING_SIZE; i++) {
1613		struct vio_net_desc *d;
1614		void *skb = port->tx_bufs[i].skb;
1615
1616		if (!skb)
1617			continue;
1618
1619		d = vio_dring_entry(dr, i);
1620
1621		ldc_unmap(port->vio.lp,
1622			  port->tx_bufs[i].cookies,
1623			  port->tx_bufs[i].ncookies);
1624		dev_kfree_skb(skb);
1625		port->tx_bufs[i].skb = NULL;
1626		d->hdr.state = VIO_DESC_FREE;
1627	}
1628	ldc_free_exp_dring(port->vio.lp, dr->base,
1629			   (dr->entry_size * dr->num_entries),
1630			   dr->cookies, dr->ncookies);
1631	dr->base = NULL;
1632	dr->entry_size = 0;
1633	dr->num_entries = 0;
1634	dr->pending = 0;
1635	dr->ncookies = 0;
1636}
1637EXPORT_SYMBOL_GPL(sunvnet_port_free_tx_bufs_common);
1638
1639static void vnet_port_reset(struct vnet_port *port)
1640{
1641	del_timer(&port->clean_timer);
1642	sunvnet_port_free_tx_bufs_common(port);
1643	port->rmtu = 0;
1644	port->tso = true;
1645	port->tsolen = 0;
1646}
1647
1648static int vnet_port_alloc_tx_ring(struct vnet_port *port)
1649{
1650	struct vio_dring_state *dr;
1651	unsigned long len, elen;
1652	int i, err, ncookies;
1653	void *dring;
1654
1655	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1656
1657	elen = sizeof(struct vio_net_desc) +
1658	       sizeof(struct ldc_trans_cookie) * 2;
1659	if (vio_version_after_eq(&port->vio, 1, 7))
1660		elen += sizeof(struct vio_net_dext);
1661	len = VNET_TX_RING_SIZE * elen;
1662
1663	ncookies = VIO_MAX_RING_COOKIES;
1664	dring = ldc_alloc_exp_dring(port->vio.lp, len,
1665				    dr->cookies, &ncookies,
1666				    (LDC_MAP_SHADOW |
1667				     LDC_MAP_DIRECT |
1668				     LDC_MAP_RW));
1669	if (IS_ERR(dring)) {
1670		err = PTR_ERR(dring);
1671		goto err_out;
1672	}
1673
1674	dr->base = dring;
1675	dr->entry_size = elen;
1676	dr->num_entries = VNET_TX_RING_SIZE;
1677	dr->prod = 0;
1678	dr->cons = 0;
1679	port->start_cons  = true; /* need an initial trigger */
1680	dr->pending = VNET_TX_RING_SIZE;
1681	dr->ncookies = ncookies;
1682
1683	for (i = 0; i < VNET_TX_RING_SIZE; ++i) {
1684		struct vio_net_desc *d;
1685
1686		d = vio_dring_entry(dr, i);
1687		d->hdr.state = VIO_DESC_FREE;
1688	}
1689	return 0;
1690
1691err_out:
1692	sunvnet_port_free_tx_bufs_common(port);
1693
1694	return err;
1695}
1696
1697#ifdef CONFIG_NET_POLL_CONTROLLER
1698void sunvnet_poll_controller_common(struct net_device *dev, struct vnet *vp)
1699{
1700	struct vnet_port *port;
1701	unsigned long flags;
1702
1703	spin_lock_irqsave(&vp->lock, flags);
1704	if (!list_empty(&vp->port_list)) {
1705		port = list_entry(vp->port_list.next, struct vnet_port, list);
1706		napi_schedule(&port->napi);
1707	}
1708	spin_unlock_irqrestore(&vp->lock, flags);
1709}
1710EXPORT_SYMBOL_GPL(sunvnet_poll_controller_common);
1711#endif
1712
1713void sunvnet_port_add_txq_common(struct vnet_port *port)
1714{
1715	struct vnet *vp = port->vp;
1716	int n;
1717
1718	n = vp->nports++;
1719	n = n & (VNET_MAX_TXQS - 1);
1720	port->q_index = n;
1721	netif_tx_wake_queue(netdev_get_tx_queue(VNET_PORT_TO_NET_DEVICE(port),
1722						port->q_index));
1723}
1724EXPORT_SYMBOL_GPL(sunvnet_port_add_txq_common);
1725
1726void sunvnet_port_rm_txq_common(struct vnet_port *port)
1727{
1728	port->vp->nports--;
1729	netif_tx_stop_queue(netdev_get_tx_queue(VNET_PORT_TO_NET_DEVICE(port),
1730						port->q_index));
1731}
1732EXPORT_SYMBOL_GPL(sunvnet_port_rm_txq_common);