1/* sunvnet.c: Sun LDOM Virtual Network Driver.
2 *
3 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
4 */
5
6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8#include <linux/module.h>
9#include <linux/kernel.h>
10#include <linux/types.h>
11#include <linux/slab.h>
12#include <linux/delay.h>
13#include <linux/init.h>
14#include <linux/netdevice.h>
15#include <linux/ethtool.h>
16#include <linux/etherdevice.h>
17#include <linux/mutex.h>
18#include <linux/highmem.h>
19#include <linux/if_vlan.h>
20
21#if IS_ENABLED(CONFIG_IPV6)
22#include <linux/icmpv6.h>
23#endif
24
25#include <net/ip.h>
26#include <net/icmp.h>
27#include <net/route.h>
28
29#include <asm/vio.h>
30#include <asm/ldc.h>
31
32#include "sunvnet.h"
33
34#define DRV_MODULE_NAME		"sunvnet"
35#define DRV_MODULE_VERSION	"1.0"
36#define DRV_MODULE_RELDATE	"June 25, 2007"
37
38static char version[] =
39	DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
40MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
41MODULE_DESCRIPTION("Sun LDOM virtual network driver");
42MODULE_LICENSE("GPL");
43MODULE_VERSION(DRV_MODULE_VERSION);
44
45#define	VNET_MAX_TXQS		16
46
47/* Heuristic for the number of times to exponentially backoff and
48 * retry sending an LDC trigger when EAGAIN is encountered
49 */
50#define	VNET_MAX_RETRIES	10
51
52static int __vnet_tx_trigger(struct vnet_port *port, u32 start);
53static void vnet_port_reset(struct vnet_port *port);
54
55/* Ordered from largest major to lowest */
56static struct vio_version vnet_versions[] = {
57	{ .major = 1, .minor = 8 },
58	{ .major = 1, .minor = 7 },
59	{ .major = 1, .minor = 6 },
60	{ .major = 1, .minor = 0 },
61};
62
63static inline u32 vnet_tx_dring_avail(struct vio_dring_state *dr)
64{
65	return vio_dring_avail(dr, VNET_TX_RING_SIZE);
66}
67
68static int vnet_handle_unknown(struct vnet_port *port, void *arg)
69{
70	struct vio_msg_tag *pkt = arg;
71
72	pr_err("Received unknown msg [%02x:%02x:%04x:%08x]\n",
73	       pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
74	pr_err("Resetting connection\n");
75
76	ldc_disconnect(port->vio.lp);
77
78	return -ECONNRESET;
79}
80
81static int vnet_port_alloc_tx_ring(struct vnet_port *port);
82
83static int vnet_send_attr(struct vio_driver_state *vio)
84{
85	struct vnet_port *port = to_vnet_port(vio);
86	struct net_device *dev = port->vp->dev;
87	struct vio_net_attr_info pkt;
88	int framelen = ETH_FRAME_LEN;
89	int i, err;
90
91	err = vnet_port_alloc_tx_ring(to_vnet_port(vio));
92	if (err)
93		return err;
94
95	memset(&pkt, 0, sizeof(pkt));
96	pkt.tag.type = VIO_TYPE_CTRL;
97	pkt.tag.stype = VIO_SUBTYPE_INFO;
98	pkt.tag.stype_env = VIO_ATTR_INFO;
99	pkt.tag.sid = vio_send_sid(vio);
100	if (vio_version_before(vio, 1, 2))
101		pkt.xfer_mode = VIO_DRING_MODE;
102	else
103		pkt.xfer_mode = VIO_NEW_DRING_MODE;
104	pkt.addr_type = VNET_ADDR_ETHERMAC;
105	pkt.ack_freq = 0;
106	for (i = 0; i < 6; i++)
107		pkt.addr |= (u64)dev->dev_addr[i] << ((5 - i) * 8);
108	if (vio_version_after(vio, 1, 3)) {
109		if (port->rmtu) {
110			port->rmtu = min(VNET_MAXPACKET, port->rmtu);
111			pkt.mtu = port->rmtu;
112		} else {
113			port->rmtu = VNET_MAXPACKET;
114			pkt.mtu = port->rmtu;
115		}
116		if (vio_version_after_eq(vio, 1, 6))
117			pkt.options = VIO_TX_DRING;
118	} else if (vio_version_before(vio, 1, 3)) {
119		pkt.mtu = framelen;
120	} else { /* v1.3 */
121		pkt.mtu = framelen + VLAN_HLEN;
122	}
123
124	pkt.cflags = 0;
125	if (vio_version_after_eq(vio, 1, 7) && port->tso) {
126		pkt.cflags |= VNET_LSO_IPV4_CAPAB;
127		if (!port->tsolen)
128			port->tsolen = VNET_MAXTSO;
129		pkt.ipv4_lso_maxlen = port->tsolen;
130	}
131
132	pkt.plnk_updt = PHYSLINK_UPDATE_NONE;
133
134	viodbg(HS, "SEND NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
135	       "ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] mtu[%llu] "
136	       "cflags[0x%04x] lso_max[%u]\n",
137	       pkt.xfer_mode, pkt.addr_type,
138	       (unsigned long long)pkt.addr,
139	       pkt.ack_freq, pkt.plnk_updt, pkt.options,
140	       (unsigned long long)pkt.mtu, pkt.cflags, pkt.ipv4_lso_maxlen);
141
142
143	return vio_ldc_send(vio, &pkt, sizeof(pkt));
144}
145
146static int handle_attr_info(struct vio_driver_state *vio,
147			    struct vio_net_attr_info *pkt)
148{
149	struct vnet_port *port = to_vnet_port(vio);
150	u64	localmtu;
151	u8	xfer_mode;
152
153	viodbg(HS, "GOT NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
154	       "ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] mtu[%llu] "
155	       " (rmtu[%llu]) cflags[0x%04x] lso_max[%u]\n",
156	       pkt->xfer_mode, pkt->addr_type,
157	       (unsigned long long)pkt->addr,
158	       pkt->ack_freq, pkt->plnk_updt, pkt->options,
159	       (unsigned long long)pkt->mtu, port->rmtu, pkt->cflags,
160	       pkt->ipv4_lso_maxlen);
161
162	pkt->tag.sid = vio_send_sid(vio);
163
164	xfer_mode = pkt->xfer_mode;
165	/* for version < 1.2, VIO_DRING_MODE = 0x3 and no bitmask */
166	if (vio_version_before(vio, 1, 2) && xfer_mode == VIO_DRING_MODE)
167		xfer_mode = VIO_NEW_DRING_MODE;
168
169	/* MTU negotiation:
170	 *	< v1.3 - ETH_FRAME_LEN exactly
171	 *	> v1.3 - MIN(pkt.mtu, VNET_MAXPACKET, port->rmtu) and change
172	 *			pkt->mtu for ACK
173	 *	= v1.3 - ETH_FRAME_LEN + VLAN_HLEN exactly
174	 */
175	if (vio_version_before(vio, 1, 3)) {
176		localmtu = ETH_FRAME_LEN;
177	} else if (vio_version_after(vio, 1, 3)) {
178		localmtu = port->rmtu ? port->rmtu : VNET_MAXPACKET;
179		localmtu = min(pkt->mtu, localmtu);
180		pkt->mtu = localmtu;
181	} else { /* v1.3 */
182		localmtu = ETH_FRAME_LEN + VLAN_HLEN;
183	}
184	port->rmtu = localmtu;
185
186	/* LSO negotiation */
187	if (vio_version_after_eq(vio, 1, 7))
188		port->tso &= !!(pkt->cflags & VNET_LSO_IPV4_CAPAB);
189	else
190		port->tso = false;
191	if (port->tso) {
192		if (!port->tsolen)
193			port->tsolen = VNET_MAXTSO;
194		port->tsolen = min(port->tsolen, pkt->ipv4_lso_maxlen);
195		if (port->tsolen < VNET_MINTSO) {
196			port->tso = false;
197			port->tsolen = 0;
198			pkt->cflags &= ~VNET_LSO_IPV4_CAPAB;
199		}
200		pkt->ipv4_lso_maxlen = port->tsolen;
201	} else {
202		pkt->cflags &= ~VNET_LSO_IPV4_CAPAB;
203		pkt->ipv4_lso_maxlen = 0;
204	}
205
206	/* for version >= 1.6, ACK packet mode we support */
207	if (vio_version_after_eq(vio, 1, 6)) {
208		pkt->xfer_mode = VIO_NEW_DRING_MODE;
209		pkt->options = VIO_TX_DRING;
210	}
211
212	if (!(xfer_mode | VIO_NEW_DRING_MODE) ||
213	    pkt->addr_type != VNET_ADDR_ETHERMAC ||
214	    pkt->mtu != localmtu) {
215		viodbg(HS, "SEND NET ATTR NACK\n");
216
217		pkt->tag.stype = VIO_SUBTYPE_NACK;
218
219		(void) vio_ldc_send(vio, pkt, sizeof(*pkt));
220
221		return -ECONNRESET;
222	} else {
223		viodbg(HS, "SEND NET ATTR ACK xmode[0x%x] atype[0x%x] "
224		       "addr[%llx] ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] "
225		       "mtu[%llu] (rmtu[%llu]) cflags[0x%04x] lso_max[%u]\n",
226		       pkt->xfer_mode, pkt->addr_type,
227		       (unsigned long long)pkt->addr,
228		       pkt->ack_freq, pkt->plnk_updt, pkt->options,
229		       (unsigned long long)pkt->mtu, port->rmtu, pkt->cflags,
230		       pkt->ipv4_lso_maxlen);
231
232		pkt->tag.stype = VIO_SUBTYPE_ACK;
233
234		return vio_ldc_send(vio, pkt, sizeof(*pkt));
235	}
236
237}
238
239static int handle_attr_ack(struct vio_driver_state *vio,
240			   struct vio_net_attr_info *pkt)
241{
242	viodbg(HS, "GOT NET ATTR ACK\n");
243
244	return 0;
245}
246
247static int handle_attr_nack(struct vio_driver_state *vio,
248			    struct vio_net_attr_info *pkt)
249{
250	viodbg(HS, "GOT NET ATTR NACK\n");
251
252	return -ECONNRESET;
253}
254
255static int vnet_handle_attr(struct vio_driver_state *vio, void *arg)
256{
257	struct vio_net_attr_info *pkt = arg;
258
259	switch (pkt->tag.stype) {
260	case VIO_SUBTYPE_INFO:
261		return handle_attr_info(vio, pkt);
262
263	case VIO_SUBTYPE_ACK:
264		return handle_attr_ack(vio, pkt);
265
266	case VIO_SUBTYPE_NACK:
267		return handle_attr_nack(vio, pkt);
268
269	default:
270		return -ECONNRESET;
271	}
272}
273
274static void vnet_handshake_complete(struct vio_driver_state *vio)
275{
276	struct vio_dring_state *dr;
277
278	dr = &vio->drings[VIO_DRIVER_RX_RING];
279	dr->snd_nxt = dr->rcv_nxt = 1;
280
281	dr = &vio->drings[VIO_DRIVER_TX_RING];
282	dr->snd_nxt = dr->rcv_nxt = 1;
283}
284
285/* The hypervisor interface that implements copying to/from imported
286 * memory from another domain requires that copies are done to 8-byte
287 * aligned buffers, and that the lengths of such copies are also 8-byte
288 * multiples.
289 *
290 * So we align skb->data to an 8-byte multiple and pad-out the data
291 * area so we can round the copy length up to the next multiple of
292 * 8 for the copy.
293 *
294 * The transmitter puts the actual start of the packet 6 bytes into
295 * the buffer it sends over, so that the IP headers after the ethernet
296 * header are aligned properly.  These 6 bytes are not in the descriptor
297 * length, they are simply implied.  This offset is represented using
298 * the VNET_PACKET_SKIP macro.
299 */
300static struct sk_buff *alloc_and_align_skb(struct net_device *dev,
301					   unsigned int len)
302{
303	struct sk_buff *skb = netdev_alloc_skb(dev, len+VNET_PACKET_SKIP+8+8);
304	unsigned long addr, off;
305
306	if (unlikely(!skb))
307		return NULL;
308
309	addr = (unsigned long) skb->data;
310	off = ((addr + 7UL) & ~7UL) - addr;
311	if (off)
312		skb_reserve(skb, off);
313
314	return skb;
315}
316
317static inline void vnet_fullcsum(struct sk_buff *skb)
318{
319	struct iphdr *iph = ip_hdr(skb);
320	int offset = skb_transport_offset(skb);
321
322	if (skb->protocol != htons(ETH_P_IP))
323		return;
324	if (iph->protocol != IPPROTO_TCP &&
325	    iph->protocol != IPPROTO_UDP)
326		return;
327	skb->ip_summed = CHECKSUM_NONE;
328	skb->csum_level = 1;
329	skb->csum = 0;
330	if (iph->protocol == IPPROTO_TCP) {
331		struct tcphdr *ptcp = tcp_hdr(skb);
332
333		ptcp->check = 0;
334		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
335		ptcp->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
336						skb->len - offset, IPPROTO_TCP,
337						skb->csum);
338	} else if (iph->protocol == IPPROTO_UDP) {
339		struct udphdr *pudp = udp_hdr(skb);
340
341		pudp->check = 0;
342		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
343		pudp->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
344						skb->len - offset, IPPROTO_UDP,
345						skb->csum);
346	}
347}
348
349static int vnet_rx_one(struct vnet_port *port, struct vio_net_desc *desc)
350{
351	struct net_device *dev = port->vp->dev;
352	unsigned int len = desc->size;
353	unsigned int copy_len;
354	struct sk_buff *skb;
355	int maxlen;
356	int err;
357
358	err = -EMSGSIZE;
359	if (port->tso && port->tsolen > port->rmtu)
360		maxlen = port->tsolen;
361	else
362		maxlen = port->rmtu;
363	if (unlikely(len < ETH_ZLEN || len > maxlen)) {
364		dev->stats.rx_length_errors++;
365		goto out_dropped;
366	}
367
368	skb = alloc_and_align_skb(dev, len);
369	err = -ENOMEM;
370	if (unlikely(!skb)) {
371		dev->stats.rx_missed_errors++;
372		goto out_dropped;
373	}
374
375	copy_len = (len + VNET_PACKET_SKIP + 7U) & ~7U;
376	skb_put(skb, copy_len);
377	err = ldc_copy(port->vio.lp, LDC_COPY_IN,
378		       skb->data, copy_len, 0,
379		       desc->cookies, desc->ncookies);
380	if (unlikely(err < 0)) {
381		dev->stats.rx_frame_errors++;
382		goto out_free_skb;
383	}
384
385	skb_pull(skb, VNET_PACKET_SKIP);
386	skb_trim(skb, len);
387	skb->protocol = eth_type_trans(skb, dev);
388
389	if (vio_version_after_eq(&port->vio, 1, 8)) {
390		struct vio_net_dext *dext = vio_net_ext(desc);
391
392		if (dext->flags & VNET_PKT_HCK_IPV4_HDRCKSUM) {
393			if (skb->protocol == ETH_P_IP) {
394				struct iphdr *iph = (struct iphdr *)skb->data;
395
396				iph->check = 0;
397				ip_send_check(iph);
398			}
399		}
400		if ((dext->flags & VNET_PKT_HCK_FULLCKSUM) &&
401		    skb->ip_summed == CHECKSUM_NONE)
402			vnet_fullcsum(skb);
403		if (dext->flags & VNET_PKT_HCK_IPV4_HDRCKSUM_OK) {
404			skb->ip_summed = CHECKSUM_PARTIAL;
405			skb->csum_level = 0;
406			if (dext->flags & VNET_PKT_HCK_FULLCKSUM_OK)
407				skb->csum_level = 1;
408		}
409	}
410
411	skb->ip_summed = port->switch_port ? CHECKSUM_NONE : CHECKSUM_PARTIAL;
412
413	dev->stats.rx_packets++;
414	dev->stats.rx_bytes += len;
415	napi_gro_receive(&port->napi, skb);
416	return 0;
417
418out_free_skb:
419	kfree_skb(skb);
420
421out_dropped:
422	dev->stats.rx_dropped++;
423	return err;
424}
425
426static int vnet_send_ack(struct vnet_port *port, struct vio_dring_state *dr,
427			 u32 start, u32 end, u8 vio_dring_state)
428{
429	struct vio_dring_data hdr = {
430		.tag = {
431			.type		= VIO_TYPE_DATA,
432			.stype		= VIO_SUBTYPE_ACK,
433			.stype_env	= VIO_DRING_DATA,
434			.sid		= vio_send_sid(&port->vio),
435		},
436		.dring_ident		= dr->ident,
437		.start_idx		= start,
438		.end_idx		= end,
439		.state			= vio_dring_state,
440	};
441	int err, delay;
442	int retries = 0;
443
444	hdr.seq = dr->snd_nxt;
445	delay = 1;
446	do {
447		err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
448		if (err > 0) {
449			dr->snd_nxt++;
450			break;
451		}
452		udelay(delay);
453		if ((delay <<= 1) > 128)
454			delay = 128;
455		if (retries++ > VNET_MAX_RETRIES) {
456			pr_info("ECONNRESET %x:%x:%x:%x:%x:%x\n",
457				port->raddr[0], port->raddr[1],
458				port->raddr[2], port->raddr[3],
459				port->raddr[4], port->raddr[5]);
460			break;
461		}
462	} while (err == -EAGAIN);
463
464	if (err <= 0 && vio_dring_state == VIO_DRING_STOPPED) {
465		port->stop_rx_idx = end;
466		port->stop_rx = true;
467	} else {
468		port->stop_rx_idx = 0;
469		port->stop_rx = false;
470	}
471
472	return err;
473}
474
475static struct vio_net_desc *get_rx_desc(struct vnet_port *port,
476					struct vio_dring_state *dr,
477					u32 index)
478{
479	struct vio_net_desc *desc = port->vio.desc_buf;
480	int err;
481
482	err = ldc_get_dring_entry(port->vio.lp, desc, dr->entry_size,
483				  (index * dr->entry_size),
484				  dr->cookies, dr->ncookies);
485	if (err < 0)
486		return ERR_PTR(err);
487
488	return desc;
489}
490
491static int put_rx_desc(struct vnet_port *port,
492		       struct vio_dring_state *dr,
493		       struct vio_net_desc *desc,
494		       u32 index)
495{
496	int err;
497
498	err = ldc_put_dring_entry(port->vio.lp, desc, dr->entry_size,
499				  (index * dr->entry_size),
500				  dr->cookies, dr->ncookies);
501	if (err < 0)
502		return err;
503
504	return 0;
505}
506
507static int vnet_walk_rx_one(struct vnet_port *port,
508			    struct vio_dring_state *dr,
509			    u32 index, int *needs_ack)
510{
511	struct vio_net_desc *desc = get_rx_desc(port, dr, index);
512	struct vio_driver_state *vio = &port->vio;
513	int err;
514
515	BUG_ON(desc == NULL);
516	if (IS_ERR(desc))
517		return PTR_ERR(desc);
518
519	if (desc->hdr.state != VIO_DESC_READY)
520		return 1;
521
522	dma_rmb();
523
524	viodbg(DATA, "vio_walk_rx_one desc[%02x:%02x:%08x:%08x:%llx:%llx]\n",
525	       desc->hdr.state, desc->hdr.ack,
526	       desc->size, desc->ncookies,
527	       desc->cookies[0].cookie_addr,
528	       desc->cookies[0].cookie_size);
529
530	err = vnet_rx_one(port, desc);
531	if (err == -ECONNRESET)
532		return err;
533	desc->hdr.state = VIO_DESC_DONE;
534	err = put_rx_desc(port, dr, desc, index);
535	if (err < 0)
536		return err;
537	*needs_ack = desc->hdr.ack;
538	return 0;
539}
540
541static int vnet_walk_rx(struct vnet_port *port, struct vio_dring_state *dr,
542			u32 start, u32 end, int *npkts, int budget)
543{
544	struct vio_driver_state *vio = &port->vio;
545	int ack_start = -1, ack_end = -1;
546	bool send_ack = true;
547
548	end = (end == (u32) -1) ? vio_dring_prev(dr, start)
549				: vio_dring_next(dr, end);
550
551	viodbg(DATA, "vnet_walk_rx start[%08x] end[%08x]\n", start, end);
552
553	while (start != end) {
554		int ack = 0, err = vnet_walk_rx_one(port, dr, start, &ack);
555		if (err == -ECONNRESET)
556			return err;
557		if (err != 0)
558			break;
559		(*npkts)++;
560		if (ack_start == -1)
561			ack_start = start;
562		ack_end = start;
563		start = vio_dring_next(dr, start);
564		if (ack && start != end) {
565			err = vnet_send_ack(port, dr, ack_start, ack_end,
566					    VIO_DRING_ACTIVE);
567			if (err == -ECONNRESET)
568				return err;
569			ack_start = -1;
570		}
571		if ((*npkts) >= budget) {
572			send_ack = false;
573			break;
574		}
575	}
576	if (unlikely(ack_start == -1))
577		ack_start = ack_end = vio_dring_prev(dr, start);
578	if (send_ack) {
579		port->napi_resume = false;
580		return vnet_send_ack(port, dr, ack_start, ack_end,
581				     VIO_DRING_STOPPED);
582	} else  {
583		port->napi_resume = true;
584		port->napi_stop_idx = ack_end;
585		return 1;
586	}
587}
588
589static int vnet_rx(struct vnet_port *port, void *msgbuf, int *npkts,
590		   int budget)
591{
592	struct vio_dring_data *pkt = msgbuf;
593	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_RX_RING];
594	struct vio_driver_state *vio = &port->vio;
595
596	viodbg(DATA, "vnet_rx stype_env[%04x] seq[%016llx] rcv_nxt[%016llx]\n",
597	       pkt->tag.stype_env, pkt->seq, dr->rcv_nxt);
598
599	if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
600		return 0;
601	if (unlikely(pkt->seq != dr->rcv_nxt)) {
602		pr_err("RX out of sequence seq[0x%llx] rcv_nxt[0x%llx]\n",
603		       pkt->seq, dr->rcv_nxt);
604		return 0;
605	}
606
607	if (!port->napi_resume)
608		dr->rcv_nxt++;
609
610	/* XXX Validate pkt->start_idx and pkt->end_idx XXX */
611
612	return vnet_walk_rx(port, dr, pkt->start_idx, pkt->end_idx,
613			    npkts, budget);
614}
615
616static int idx_is_pending(struct vio_dring_state *dr, u32 end)
617{
618	u32 idx = dr->cons;
619	int found = 0;
620
621	while (idx != dr->prod) {
622		if (idx == end) {
623			found = 1;
624			break;
625		}
626		idx = vio_dring_next(dr, idx);
627	}
628	return found;
629}
630
631static int vnet_ack(struct vnet_port *port, void *msgbuf)
632{
633	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
634	struct vio_dring_data *pkt = msgbuf;
635	struct net_device *dev;
636	struct vnet *vp;
637	u32 end;
638	struct vio_net_desc *desc;
639	struct netdev_queue *txq;
640
641	if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
642		return 0;
643
644	end = pkt->end_idx;
645	vp = port->vp;
646	dev = vp->dev;
647	netif_tx_lock(dev);
648	if (unlikely(!idx_is_pending(dr, end))) {
649		netif_tx_unlock(dev);
650		return 0;
651	}
652
653	/* sync for race conditions with vnet_start_xmit() and tell xmit it
654	 * is time to send a trigger.
655	 */
656	dr->cons = vio_dring_next(dr, end);
657	desc = vio_dring_entry(dr, dr->cons);
658	if (desc->hdr.state == VIO_DESC_READY && !port->start_cons) {
659		/* vnet_start_xmit() just populated this dring but missed
660		 * sending the "start" LDC message to the consumer.
661		 * Send a "start" trigger on its behalf.
662		 */
663		if (__vnet_tx_trigger(port, dr->cons) > 0)
664			port->start_cons = false;
665		else
666			port->start_cons = true;
667	} else {
668		port->start_cons = true;
669	}
670	netif_tx_unlock(dev);
671
672	txq = netdev_get_tx_queue(dev, port->q_index);
673	if (unlikely(netif_tx_queue_stopped(txq) &&
674		     vnet_tx_dring_avail(dr) >= VNET_TX_WAKEUP_THRESH(dr)))
675		return 1;
676
677	return 0;
678}
679
680static int vnet_nack(struct vnet_port *port, void *msgbuf)
681{
682	/* XXX just reset or similar XXX */
683	return 0;
684}
685
686static int handle_mcast(struct vnet_port *port, void *msgbuf)
687{
688	struct vio_net_mcast_info *pkt = msgbuf;
689
690	if (pkt->tag.stype != VIO_SUBTYPE_ACK)
691		pr_err("%s: Got unexpected MCAST reply [%02x:%02x:%04x:%08x]\n",
692		       port->vp->dev->name,
693		       pkt->tag.type,
694		       pkt->tag.stype,
695		       pkt->tag.stype_env,
696		       pkt->tag.sid);
697
698	return 0;
699}
700
701/* Got back a STOPPED LDC message on port. If the queue is stopped,
702 * wake it up so that we'll send out another START message at the
703 * next TX.
704 */
705static void maybe_tx_wakeup(struct vnet_port *port)
706{
707	struct netdev_queue *txq;
708
709	txq = netdev_get_tx_queue(port->vp->dev, port->q_index);
710	__netif_tx_lock(txq, smp_processor_id());
711	if (likely(netif_tx_queue_stopped(txq))) {
712		struct vio_dring_state *dr;
713
714		dr = &port->vio.drings[VIO_DRIVER_TX_RING];
715		netif_tx_wake_queue(txq);
716	}
717	__netif_tx_unlock(txq);
718}
719
720static inline bool port_is_up(struct vnet_port *vnet)
721{
722	struct vio_driver_state *vio = &vnet->vio;
723
724	return !!(vio->hs_state & VIO_HS_COMPLETE);
725}
726
727static int vnet_event_napi(struct vnet_port *port, int budget)
728{
729	struct vio_driver_state *vio = &port->vio;
730	int tx_wakeup, err;
731	int npkts = 0;
732	int event = (port->rx_event & LDC_EVENT_RESET);
733
734ldc_ctrl:
735	if (unlikely(event == LDC_EVENT_RESET ||
736		     event == LDC_EVENT_UP)) {
737		vio_link_state_change(vio, event);
738
739		if (event == LDC_EVENT_RESET) {
740			vnet_port_reset(port);
741			vio_port_up(vio);
742		}
743		port->rx_event = 0;
744		return 0;
745	}
746	/* We may have multiple LDC events in rx_event. Unroll send_events() */
747	event = (port->rx_event & LDC_EVENT_UP);
748	port->rx_event &= ~(LDC_EVENT_RESET|LDC_EVENT_UP);
749	if (event == LDC_EVENT_UP)
750		goto ldc_ctrl;
751	event = port->rx_event;
752	if (!(event & LDC_EVENT_DATA_READY))
753		return 0;
754
755	/* we dont expect any other bits than RESET, UP, DATA_READY */
756	BUG_ON(event != LDC_EVENT_DATA_READY);
757
758	tx_wakeup = err = 0;
759	while (1) {
760		union {
761			struct vio_msg_tag tag;
762			u64 raw[8];
763		} msgbuf;
764
765		if (port->napi_resume) {
766			struct vio_dring_data *pkt =
767				(struct vio_dring_data *)&msgbuf;
768			struct vio_dring_state *dr =
769				&port->vio.drings[VIO_DRIVER_RX_RING];
770
771			pkt->tag.type = VIO_TYPE_DATA;
772			pkt->tag.stype = VIO_SUBTYPE_INFO;
773			pkt->tag.stype_env = VIO_DRING_DATA;
774			pkt->seq = dr->rcv_nxt;
775			pkt->start_idx = vio_dring_next(dr, port->napi_stop_idx);
776			pkt->end_idx = -1;
777			goto napi_resume;
778		}
779		err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
780		if (unlikely(err < 0)) {
781			if (err == -ECONNRESET)
782				vio_conn_reset(vio);
783			break;
784		}
785		if (err == 0)
786			break;
787		viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
788		       msgbuf.tag.type,
789		       msgbuf.tag.stype,
790		       msgbuf.tag.stype_env,
791		       msgbuf.tag.sid);
792		err = vio_validate_sid(vio, &msgbuf.tag);
793		if (err < 0)
794			break;
795napi_resume:
796		if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
797			if (msgbuf.tag.stype == VIO_SUBTYPE_INFO) {
798				if (!port_is_up(port)) {
799					/* failures like handshake_failure()
800					 * may have cleaned up dring, but
801					 * NAPI polling may bring us here.
802					 */
803					err = -ECONNRESET;
804					break;
805				}
806				err = vnet_rx(port, &msgbuf, &npkts, budget);
807				if (npkts >= budget)
808					break;
809				if (npkts == 0)
810					break;
811			} else if (msgbuf.tag.stype == VIO_SUBTYPE_ACK) {
812				err = vnet_ack(port, &msgbuf);
813				if (err > 0)
814					tx_wakeup |= err;
815			} else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK) {
816				err = vnet_nack(port, &msgbuf);
817			}
818		} else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
819			if (msgbuf.tag.stype_env == VNET_MCAST_INFO)
820				err = handle_mcast(port, &msgbuf);
821			else
822				err = vio_control_pkt_engine(vio, &msgbuf);
823			if (err)
824				break;
825		} else {
826			err = vnet_handle_unknown(port, &msgbuf);
827		}
828		if (err == -ECONNRESET)
829			break;
830	}
831	if (unlikely(tx_wakeup && err != -ECONNRESET))
832		maybe_tx_wakeup(port);
833	return npkts;
834}
835
836static int vnet_poll(struct napi_struct *napi, int budget)
837{
838	struct vnet_port *port = container_of(napi, struct vnet_port, napi);
839	struct vio_driver_state *vio = &port->vio;
840	int processed = vnet_event_napi(port, budget);
841
842	if (processed < budget) {
843		napi_complete(napi);
844		port->rx_event &= ~LDC_EVENT_DATA_READY;
845		vio_set_intr(vio->vdev->rx_ino, HV_INTR_ENABLED);
846	}
847	return processed;
848}
849
850static void vnet_event(void *arg, int event)
851{
852	struct vnet_port *port = arg;
853	struct vio_driver_state *vio = &port->vio;
854
855	port->rx_event |= event;
856	vio_set_intr(vio->vdev->rx_ino, HV_INTR_DISABLED);
857	napi_schedule(&port->napi);
858
859}
860
861static int __vnet_tx_trigger(struct vnet_port *port, u32 start)
862{
863	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
864	struct vio_dring_data hdr = {
865		.tag = {
866			.type		= VIO_TYPE_DATA,
867			.stype		= VIO_SUBTYPE_INFO,
868			.stype_env	= VIO_DRING_DATA,
869			.sid		= vio_send_sid(&port->vio),
870		},
871		.dring_ident		= dr->ident,
872		.start_idx		= start,
873		.end_idx		= (u32) -1,
874	};
875	int err, delay;
876	int retries = 0;
877
878	if (port->stop_rx) {
879		err = vnet_send_ack(port,
880				    &port->vio.drings[VIO_DRIVER_RX_RING],
881				    port->stop_rx_idx, -1,
882				    VIO_DRING_STOPPED);
883		if (err <= 0)
884			return err;
885	}
886
887	hdr.seq = dr->snd_nxt;
888	delay = 1;
889	do {
890		err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
891		if (err > 0) {
892			dr->snd_nxt++;
893			break;
894		}
895		udelay(delay);
896		if ((delay <<= 1) > 128)
897			delay = 128;
898		if (retries++ > VNET_MAX_RETRIES)
899			break;
900	} while (err == -EAGAIN);
901
902	return err;
903}
904
905struct vnet_port *__tx_port_find(struct vnet *vp, struct sk_buff *skb)
906{
907	unsigned int hash = vnet_hashfn(skb->data);
908	struct hlist_head *hp = &vp->port_hash[hash];
909	struct vnet_port *port;
910
911	hlist_for_each_entry_rcu(port, hp, hash) {
912		if (!port_is_up(port))
913			continue;
914		if (ether_addr_equal(port->raddr, skb->data))
915			return port;
916	}
917	list_for_each_entry_rcu(port, &vp->port_list, list) {
918		if (!port->switch_port)
919			continue;
920		if (!port_is_up(port))
921			continue;
922		return port;
923	}
924	return NULL;
925}
926
927static struct sk_buff *vnet_clean_tx_ring(struct vnet_port *port,
928					  unsigned *pending)
929{
930	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
931	struct sk_buff *skb = NULL;
932	int i, txi;
933
934	*pending = 0;
935
936	txi = dr->prod;
937	for (i = 0; i < VNET_TX_RING_SIZE; ++i) {
938		struct vio_net_desc *d;
939
940		--txi;
941		if (txi < 0)
942			txi = VNET_TX_RING_SIZE-1;
943
944		d = vio_dring_entry(dr, txi);
945
946		if (d->hdr.state == VIO_DESC_READY) {
947			(*pending)++;
948			continue;
949		}
950		if (port->tx_bufs[txi].skb) {
951			if (d->hdr.state != VIO_DESC_DONE)
952				pr_notice("invalid ring buffer state %d\n",
953					  d->hdr.state);
954			BUG_ON(port->tx_bufs[txi].skb->next);
955
956			port->tx_bufs[txi].skb->next = skb;
957			skb = port->tx_bufs[txi].skb;
958			port->tx_bufs[txi].skb = NULL;
959
960			ldc_unmap(port->vio.lp,
961				  port->tx_bufs[txi].cookies,
962				  port->tx_bufs[txi].ncookies);
963		} else if (d->hdr.state == VIO_DESC_FREE)
964			break;
965		d->hdr.state = VIO_DESC_FREE;
966	}
967	return skb;
968}
969
970static inline void vnet_free_skbs(struct sk_buff *skb)
971{
972	struct sk_buff *next;
973
974	while (skb) {
975		next = skb->next;
976		skb->next = NULL;
977		dev_kfree_skb(skb);
978		skb = next;
979	}
980}
981
982static void vnet_clean_timer_expire(unsigned long port0)
983{
984	struct vnet_port *port = (struct vnet_port *)port0;
985	struct sk_buff *freeskbs;
986	unsigned pending;
987
988	netif_tx_lock(port->vp->dev);
989	freeskbs = vnet_clean_tx_ring(port, &pending);
990	netif_tx_unlock(port->vp->dev);
991
992	vnet_free_skbs(freeskbs);
993
994	if (pending)
995		(void)mod_timer(&port->clean_timer,
996				jiffies + VNET_CLEAN_TIMEOUT);
997	 else
998		del_timer(&port->clean_timer);
999}
1000
1001static inline int vnet_skb_map(struct ldc_channel *lp, struct sk_buff *skb,
1002			       struct ldc_trans_cookie *cookies, int ncookies,
1003			       unsigned int map_perm)
1004{
1005	int i, nc, err, blen;
1006
1007	/* header */
1008	blen = skb_headlen(skb);
1009	if (blen < ETH_ZLEN)
1010		blen = ETH_ZLEN;
1011	blen += VNET_PACKET_SKIP;
1012	blen += 8 - (blen & 7);
1013
1014	err = ldc_map_single(lp, skb->data-VNET_PACKET_SKIP, blen, cookies,
1015			     ncookies, map_perm);
1016	if (err < 0)
1017		return err;
1018	nc = err;
1019
1020	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1021		skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1022		u8 *vaddr;
1023
1024		if (nc < ncookies) {
1025			vaddr = kmap_atomic(skb_frag_page(f));
1026			blen = skb_frag_size(f);
1027			blen += 8 - (blen & 7);
1028			err = ldc_map_single(lp, vaddr + f->page_offset,
1029					     blen, cookies + nc, ncookies - nc,
1030					     map_perm);
1031			kunmap_atomic(vaddr);
1032		} else {
1033			err = -EMSGSIZE;
1034		}
1035
1036		if (err < 0) {
1037			ldc_unmap(lp, cookies, nc);
1038			return err;
1039		}
1040		nc += err;
1041	}
1042	return nc;
1043}
1044
1045static inline struct sk_buff *vnet_skb_shape(struct sk_buff *skb, int ncookies)
1046{
1047	struct sk_buff *nskb;
1048	int i, len, pad, docopy;
1049
1050	len = skb->len;
1051	pad = 0;
1052	if (len < ETH_ZLEN) {
1053		pad += ETH_ZLEN - skb->len;
1054		len += pad;
1055	}
1056	len += VNET_PACKET_SKIP;
1057	pad += 8 - (len & 7);
1058
1059	/* make sure we have enough cookies and alignment in every frag */
1060	docopy = skb_shinfo(skb)->nr_frags >= ncookies;
1061	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1062		skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1063
1064		docopy |= f->page_offset & 7;
1065	}
1066	if (((unsigned long)skb->data & 7) != VNET_PACKET_SKIP ||
1067	    skb_tailroom(skb) < pad ||
1068	    skb_headroom(skb) < VNET_PACKET_SKIP || docopy) {
1069		int start = 0, offset;
1070		__wsum csum;
1071
1072		len = skb->len > ETH_ZLEN ? skb->len : ETH_ZLEN;
1073		nskb = alloc_and_align_skb(skb->dev, len);
1074		if (nskb == NULL) {
1075			dev_kfree_skb(skb);
1076			return NULL;
1077		}
1078		skb_reserve(nskb, VNET_PACKET_SKIP);
1079
1080		nskb->protocol = skb->protocol;
1081		offset = skb_mac_header(skb) - skb->data;
1082		skb_set_mac_header(nskb, offset);
1083		offset = skb_network_header(skb) - skb->data;
1084		skb_set_network_header(nskb, offset);
1085		offset = skb_transport_header(skb) - skb->data;
1086		skb_set_transport_header(nskb, offset);
1087
1088		offset = 0;
1089		nskb->csum_offset = skb->csum_offset;
1090		nskb->ip_summed = skb->ip_summed;
1091
1092		if (skb->ip_summed == CHECKSUM_PARTIAL)
1093			start = skb_checksum_start_offset(skb);
1094		if (start) {
1095			struct iphdr *iph = ip_hdr(nskb);
1096			int offset = start + nskb->csum_offset;
1097
1098			if (skb_copy_bits(skb, 0, nskb->data, start)) {
1099				dev_kfree_skb(nskb);
1100				dev_kfree_skb(skb);
1101				return NULL;
1102			}
1103			*(__sum16 *)(skb->data + offset) = 0;
1104			csum = skb_copy_and_csum_bits(skb, start,
1105						      nskb->data + start,
1106						      skb->len - start, 0);
1107			if (iph->protocol == IPPROTO_TCP ||
1108			    iph->protocol == IPPROTO_UDP) {
1109				csum = csum_tcpudp_magic(iph->saddr, iph->daddr,
1110							 skb->len - start,
1111							 iph->protocol, csum);
1112			}
1113			*(__sum16 *)(nskb->data + offset) = csum;
1114
1115			nskb->ip_summed = CHECKSUM_NONE;
1116		} else if (skb_copy_bits(skb, 0, nskb->data, skb->len)) {
1117			dev_kfree_skb(nskb);
1118			dev_kfree_skb(skb);
1119			return NULL;
1120		}
1121		(void)skb_put(nskb, skb->len);
1122		if (skb_is_gso(skb)) {
1123			skb_shinfo(nskb)->gso_size = skb_shinfo(skb)->gso_size;
1124			skb_shinfo(nskb)->gso_type = skb_shinfo(skb)->gso_type;
1125		}
1126		nskb->queue_mapping = skb->queue_mapping;
1127		dev_kfree_skb(skb);
1128		skb = nskb;
1129	}
1130	return skb;
1131}
1132
1133static u16
1134vnet_select_queue(struct net_device *dev, struct sk_buff *skb,
1135		  void *accel_priv, select_queue_fallback_t fallback)
1136{
1137	struct vnet *vp = netdev_priv(dev);
1138	struct vnet_port *port = __tx_port_find(vp, skb);
1139
1140	if (port == NULL)
1141		return 0;
1142	return port->q_index;
1143}
1144
1145static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev);
1146
1147static int vnet_handle_offloads(struct vnet_port *port, struct sk_buff *skb)
1148{
1149	struct net_device *dev = port->vp->dev;
1150	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1151	struct sk_buff *segs;
1152	int maclen, datalen;
1153	int status;
1154	int gso_size, gso_type, gso_segs;
1155	int hlen = skb_transport_header(skb) - skb_mac_header(skb);
1156	int proto = IPPROTO_IP;
1157
1158	if (skb->protocol == htons(ETH_P_IP))
1159		proto = ip_hdr(skb)->protocol;
1160	else if (skb->protocol == htons(ETH_P_IPV6))
1161		proto = ipv6_hdr(skb)->nexthdr;
1162
1163	if (proto == IPPROTO_TCP)
1164		hlen += tcp_hdr(skb)->doff * 4;
1165	else if (proto == IPPROTO_UDP)
1166		hlen += sizeof(struct udphdr);
1167	else {
1168		pr_err("vnet_handle_offloads GSO with unknown transport "
1169		       "protocol %d tproto %d\n", skb->protocol, proto);
1170		hlen = 128; /* XXX */
1171	}
1172	datalen = port->tsolen - hlen;
1173
1174	gso_size = skb_shinfo(skb)->gso_size;
1175	gso_type = skb_shinfo(skb)->gso_type;
1176	gso_segs = skb_shinfo(skb)->gso_segs;
1177
1178	if (port->tso && gso_size < datalen)
1179		gso_segs = DIV_ROUND_UP(skb->len - hlen, datalen);
1180
1181	if (unlikely(vnet_tx_dring_avail(dr) < gso_segs)) {
1182		struct netdev_queue *txq;
1183
1184		txq  = netdev_get_tx_queue(dev, port->q_index);
1185		netif_tx_stop_queue(txq);
1186		if (vnet_tx_dring_avail(dr) < skb_shinfo(skb)->gso_segs)
1187			return NETDEV_TX_BUSY;
1188		netif_tx_wake_queue(txq);
1189	}
1190
1191	maclen = skb_network_header(skb) - skb_mac_header(skb);
1192	skb_pull(skb, maclen);
1193
1194	if (port->tso && gso_size < datalen) {
1195		if (skb_unclone(skb, GFP_ATOMIC))
1196			goto out_dropped;
1197
1198		/* segment to TSO size */
1199		skb_shinfo(skb)->gso_size = datalen;
1200		skb_shinfo(skb)->gso_segs = gso_segs;
1201	}
1202	segs = skb_gso_segment(skb, dev->features & ~NETIF_F_TSO);
1203	if (IS_ERR(segs))
1204		goto out_dropped;
1205
1206	skb_push(skb, maclen);
1207	skb_reset_mac_header(skb);
1208
1209	status = 0;
1210	while (segs) {
1211		struct sk_buff *curr = segs;
1212
1213		segs = segs->next;
1214		curr->next = NULL;
1215		if (port->tso && curr->len > dev->mtu) {
1216			skb_shinfo(curr)->gso_size = gso_size;
1217			skb_shinfo(curr)->gso_type = gso_type;
1218			skb_shinfo(curr)->gso_segs =
1219				DIV_ROUND_UP(curr->len - hlen, gso_size);
1220		} else
1221			skb_shinfo(curr)->gso_size = 0;
1222
1223		skb_push(curr, maclen);
1224		skb_reset_mac_header(curr);
1225		memcpy(skb_mac_header(curr), skb_mac_header(skb),
1226		       maclen);
1227		curr->csum_start = skb_transport_header(curr) - curr->head;
1228		if (ip_hdr(curr)->protocol == IPPROTO_TCP)
1229			curr->csum_offset = offsetof(struct tcphdr, check);
1230		else if (ip_hdr(curr)->protocol == IPPROTO_UDP)
1231			curr->csum_offset = offsetof(struct udphdr, check);
1232
1233		if (!(status & NETDEV_TX_MASK))
1234			status = vnet_start_xmit(curr, dev);
1235		if (status & NETDEV_TX_MASK)
1236			dev_kfree_skb_any(curr);
1237	}
1238
1239	if (!(status & NETDEV_TX_MASK))
1240		dev_kfree_skb_any(skb);
1241	return status;
1242out_dropped:
1243	dev->stats.tx_dropped++;
1244	dev_kfree_skb_any(skb);
1245	return NETDEV_TX_OK;
1246}
1247
1248static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
1249{
1250	struct vnet *vp = netdev_priv(dev);
1251	struct vnet_port *port = NULL;
1252	struct vio_dring_state *dr;
1253	struct vio_net_desc *d;
1254	unsigned int len;
1255	struct sk_buff *freeskbs = NULL;
1256	int i, err, txi;
1257	unsigned pending = 0;
1258	struct netdev_queue *txq;
1259
1260	rcu_read_lock();
1261	port = __tx_port_find(vp, skb);
1262	if (unlikely(!port)) {
1263		rcu_read_unlock();
1264		goto out_dropped;
1265	}
1266
1267	if (skb_is_gso(skb) && skb->len > port->tsolen) {
1268		err = vnet_handle_offloads(port, skb);
1269		rcu_read_unlock();
1270		return err;
1271	}
1272
1273	if (!skb_is_gso(skb) && skb->len > port->rmtu) {
1274		unsigned long localmtu = port->rmtu - ETH_HLEN;
1275
1276		if (vio_version_after_eq(&port->vio, 1, 3))
1277			localmtu -= VLAN_HLEN;
1278
1279		if (skb->protocol == htons(ETH_P_IP)) {
1280			struct flowi4 fl4;
1281			struct rtable *rt = NULL;
1282
1283			memset(&fl4, 0, sizeof(fl4));
1284			fl4.flowi4_oif = dev->ifindex;
1285			fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);
1286			fl4.daddr = ip_hdr(skb)->daddr;
1287			fl4.saddr = ip_hdr(skb)->saddr;
1288
1289			rt = ip_route_output_key(dev_net(dev), &fl4);
1290			rcu_read_unlock();
1291			if (!IS_ERR(rt)) {
1292				skb_dst_set(skb, &rt->dst);
1293				icmp_send(skb, ICMP_DEST_UNREACH,
1294					  ICMP_FRAG_NEEDED,
1295					  htonl(localmtu));
1296			}
1297		}
1298#if IS_ENABLED(CONFIG_IPV6)
1299		else if (skb->protocol == htons(ETH_P_IPV6))
1300			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, localmtu);
1301#endif
1302		goto out_dropped;
1303	}
1304
1305	skb = vnet_skb_shape(skb, 2);
1306
1307	if (unlikely(!skb))
1308		goto out_dropped;
1309
1310	if (skb->ip_summed == CHECKSUM_PARTIAL)
1311		vnet_fullcsum(skb);
1312
1313	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1314	i = skb_get_queue_mapping(skb);
1315	txq = netdev_get_tx_queue(dev, i);
1316	if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
1317		if (!netif_tx_queue_stopped(txq)) {
1318			netif_tx_stop_queue(txq);
1319
1320			/* This is a hard error, log it. */
1321			netdev_err(dev, "BUG! Tx Ring full when queue awake!\n");
1322			dev->stats.tx_errors++;
1323		}
1324		rcu_read_unlock();
1325		return NETDEV_TX_BUSY;
1326	}
1327
1328	d = vio_dring_cur(dr);
1329
1330	txi = dr->prod;
1331
1332	freeskbs = vnet_clean_tx_ring(port, &pending);
1333
1334	BUG_ON(port->tx_bufs[txi].skb);
1335
1336	len = skb->len;
1337	if (len < ETH_ZLEN)
1338		len = ETH_ZLEN;
1339
1340	err = vnet_skb_map(port->vio.lp, skb, port->tx_bufs[txi].cookies, 2,
1341			   (LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_RW));
1342	if (err < 0) {
1343		netdev_info(dev, "tx buffer map error %d\n", err);
1344		goto out_dropped;
1345	}
1346
1347	port->tx_bufs[txi].skb = skb;
1348	skb = NULL;
1349	port->tx_bufs[txi].ncookies = err;
1350
1351	/* We don't rely on the ACKs to free the skb in vnet_start_xmit(),
1352	 * thus it is safe to not set VIO_ACK_ENABLE for each transmission:
1353	 * the protocol itself does not require it as long as the peer
1354	 * sends a VIO_SUBTYPE_ACK for VIO_DRING_STOPPED.
1355	 *
1356	 * An ACK for every packet in the ring is expensive as the
1357	 * sending of LDC messages is slow and affects performance.
1358	 */
1359	d->hdr.ack = VIO_ACK_DISABLE;
1360	d->size = len;
1361	d->ncookies = port->tx_bufs[txi].ncookies;
1362	for (i = 0; i < d->ncookies; i++)
1363		d->cookies[i] = port->tx_bufs[txi].cookies[i];
1364	if (vio_version_after_eq(&port->vio, 1, 7)) {
1365		struct vio_net_dext *dext = vio_net_ext(d);
1366
1367		memset(dext, 0, sizeof(*dext));
1368		if (skb_is_gso(port->tx_bufs[txi].skb)) {
1369			dext->ipv4_lso_mss = skb_shinfo(port->tx_bufs[txi].skb)
1370					     ->gso_size;
1371			dext->flags |= VNET_PKT_IPV4_LSO;
1372		}
1373		if (vio_version_after_eq(&port->vio, 1, 8) &&
1374		    !port->switch_port) {
1375			dext->flags |= VNET_PKT_HCK_IPV4_HDRCKSUM_OK;
1376			dext->flags |= VNET_PKT_HCK_FULLCKSUM_OK;
1377		}
1378	}
1379
1380	/* This has to be a non-SMP write barrier because we are writing
1381	 * to memory which is shared with the peer LDOM.
1382	 */
1383	dma_wmb();
1384
1385	d->hdr.state = VIO_DESC_READY;
1386
1387	/* Exactly one ldc "start" trigger (for dr->cons) needs to be sent
1388	 * to notify the consumer that some descriptors are READY.
1389	 * After that "start" trigger, no additional triggers are needed until
1390	 * a DRING_STOPPED is received from the consumer. The dr->cons field
1391	 * (set up by vnet_ack()) has the value of the next dring index
1392	 * that has not yet been ack-ed. We send a "start" trigger here
1393	 * if, and only if, start_cons is true (reset it afterward). Conversely,
1394	 * vnet_ack() should check if the dring corresponding to cons
1395	 * is marked READY, but start_cons was false.
1396	 * If so, vnet_ack() should send out the missed "start" trigger.
1397	 *
1398	 * Note that the dma_wmb() above makes sure the cookies et al. are
1399	 * not globally visible before the VIO_DESC_READY, and that the
1400	 * stores are ordered correctly by the compiler. The consumer will
1401	 * not proceed until the VIO_DESC_READY is visible assuring that
1402	 * the consumer does not observe anything related to descriptors
1403	 * out of order. The HV trap from the LDC start trigger is the
1404	 * producer to consumer announcement that work is available to the
1405	 * consumer
1406	 */
1407	if (!port->start_cons)
1408		goto ldc_start_done; /* previous trigger suffices */
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}
1454
1455static void vnet_tx_timeout(struct net_device *dev)
1456{
1457	/* XXX Implement me XXX */
1458}
1459
1460static int vnet_open(struct net_device *dev)
1461{
1462	netif_carrier_on(dev);
1463	netif_tx_start_all_queues(dev);
1464
1465	return 0;
1466}
1467
1468static int vnet_close(struct net_device *dev)
1469{
1470	netif_tx_stop_all_queues(dev);
1471	netif_carrier_off(dev);
1472
1473	return 0;
1474}
1475
1476static struct vnet_mcast_entry *__vnet_mc_find(struct vnet *vp, u8 *addr)
1477{
1478	struct vnet_mcast_entry *m;
1479
1480	for (m = vp->mcast_list; m; m = m->next) {
1481		if (ether_addr_equal(m->addr, addr))
1482			return m;
1483	}
1484	return NULL;
1485}
1486
1487static void __update_mc_list(struct vnet *vp, struct net_device *dev)
1488{
1489	struct netdev_hw_addr *ha;
1490
1491	netdev_for_each_mc_addr(ha, dev) {
1492		struct vnet_mcast_entry *m;
1493
1494		m = __vnet_mc_find(vp, ha->addr);
1495		if (m) {
1496			m->hit = 1;
1497			continue;
1498		}
1499
1500		if (!m) {
1501			m = kzalloc(sizeof(*m), GFP_ATOMIC);
1502			if (!m)
1503				continue;
1504			memcpy(m->addr, ha->addr, ETH_ALEN);
1505			m->hit = 1;
1506
1507			m->next = vp->mcast_list;
1508			vp->mcast_list = m;
1509		}
1510	}
1511}
1512
1513static void __send_mc_list(struct vnet *vp, struct vnet_port *port)
1514{
1515	struct vio_net_mcast_info info;
1516	struct vnet_mcast_entry *m, **pp;
1517	int n_addrs;
1518
1519	memset(&info, 0, sizeof(info));
1520
1521	info.tag.type = VIO_TYPE_CTRL;
1522	info.tag.stype = VIO_SUBTYPE_INFO;
1523	info.tag.stype_env = VNET_MCAST_INFO;
1524	info.tag.sid = vio_send_sid(&port->vio);
1525	info.set = 1;
1526
1527	n_addrs = 0;
1528	for (m = vp->mcast_list; m; m = m->next) {
1529		if (m->sent)
1530			continue;
1531		m->sent = 1;
1532		memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
1533		       m->addr, ETH_ALEN);
1534		if (++n_addrs == VNET_NUM_MCAST) {
1535			info.count = n_addrs;
1536
1537			(void) vio_ldc_send(&port->vio, &info,
1538					    sizeof(info));
1539			n_addrs = 0;
1540		}
1541	}
1542	if (n_addrs) {
1543		info.count = n_addrs;
1544		(void) vio_ldc_send(&port->vio, &info, sizeof(info));
1545	}
1546
1547	info.set = 0;
1548
1549	n_addrs = 0;
1550	pp = &vp->mcast_list;
1551	while ((m = *pp) != NULL) {
1552		if (m->hit) {
1553			m->hit = 0;
1554			pp = &m->next;
1555			continue;
1556		}
1557
1558		memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
1559		       m->addr, ETH_ALEN);
1560		if (++n_addrs == VNET_NUM_MCAST) {
1561			info.count = n_addrs;
1562			(void) vio_ldc_send(&port->vio, &info,
1563					    sizeof(info));
1564			n_addrs = 0;
1565		}
1566
1567		*pp = m->next;
1568		kfree(m);
1569	}
1570	if (n_addrs) {
1571		info.count = n_addrs;
1572		(void) vio_ldc_send(&port->vio, &info, sizeof(info));
1573	}
1574}
1575
1576static void vnet_set_rx_mode(struct net_device *dev)
1577{
1578	struct vnet *vp = netdev_priv(dev);
1579	struct vnet_port *port;
1580
1581	rcu_read_lock();
1582	list_for_each_entry_rcu(port, &vp->port_list, list) {
1583
1584		if (port->switch_port) {
1585			__update_mc_list(vp, dev);
1586			__send_mc_list(vp, port);
1587			break;
1588		}
1589	}
1590	rcu_read_unlock();
1591}
1592
1593static int vnet_change_mtu(struct net_device *dev, int new_mtu)
1594{
1595	if (new_mtu < 68 || new_mtu > 65535)
1596		return -EINVAL;
1597
1598	dev->mtu = new_mtu;
1599	return 0;
1600}
1601
1602static int vnet_set_mac_addr(struct net_device *dev, void *p)
1603{
1604	return -EINVAL;
1605}
1606
1607static void vnet_get_drvinfo(struct net_device *dev,
1608			     struct ethtool_drvinfo *info)
1609{
1610	strlcpy(info->driver, DRV_MODULE_NAME, sizeof(info->driver));
1611	strlcpy(info->version, DRV_MODULE_VERSION, sizeof(info->version));
1612}
1613
1614static u32 vnet_get_msglevel(struct net_device *dev)
1615{
1616	struct vnet *vp = netdev_priv(dev);
1617	return vp->msg_enable;
1618}
1619
1620static void vnet_set_msglevel(struct net_device *dev, u32 value)
1621{
1622	struct vnet *vp = netdev_priv(dev);
1623	vp->msg_enable = value;
1624}
1625
1626static const struct ethtool_ops vnet_ethtool_ops = {
1627	.get_drvinfo		= vnet_get_drvinfo,
1628	.get_msglevel		= vnet_get_msglevel,
1629	.set_msglevel		= vnet_set_msglevel,
1630	.get_link		= ethtool_op_get_link,
1631};
1632
1633static void vnet_port_free_tx_bufs(struct vnet_port *port)
1634{
1635	struct vio_dring_state *dr;
1636	int i;
1637
1638	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1639
1640	if (dr->base == NULL)
1641		return;
1642
1643	for (i = 0; i < VNET_TX_RING_SIZE; i++) {
1644		struct vio_net_desc *d;
1645		void *skb = port->tx_bufs[i].skb;
1646
1647		if (!skb)
1648			continue;
1649
1650		d = vio_dring_entry(dr, i);
1651
1652		ldc_unmap(port->vio.lp,
1653			  port->tx_bufs[i].cookies,
1654			  port->tx_bufs[i].ncookies);
1655		dev_kfree_skb(skb);
1656		port->tx_bufs[i].skb = NULL;
1657		d->hdr.state = VIO_DESC_FREE;
1658	}
1659	ldc_free_exp_dring(port->vio.lp, dr->base,
1660			   (dr->entry_size * dr->num_entries),
1661			   dr->cookies, dr->ncookies);
1662	dr->base = NULL;
1663	dr->entry_size = 0;
1664	dr->num_entries = 0;
1665	dr->pending = 0;
1666	dr->ncookies = 0;
1667}
1668
1669static void vnet_port_reset(struct vnet_port *port)
1670{
1671	del_timer(&port->clean_timer);
1672	vnet_port_free_tx_bufs(port);
1673	port->rmtu = 0;
1674	port->tso = true;
1675	port->tsolen = 0;
1676}
1677
1678static int vnet_port_alloc_tx_ring(struct vnet_port *port)
1679{
1680	struct vio_dring_state *dr;
1681	unsigned long len, elen;
1682	int i, err, ncookies;
1683	void *dring;
1684
1685	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1686
1687	elen = sizeof(struct vio_net_desc) +
1688	       sizeof(struct ldc_trans_cookie) * 2;
1689	if (vio_version_after_eq(&port->vio, 1, 7))
1690		elen += sizeof(struct vio_net_dext);
1691	len = VNET_TX_RING_SIZE * elen;
1692
1693	ncookies = VIO_MAX_RING_COOKIES;
1694	dring = ldc_alloc_exp_dring(port->vio.lp, len,
1695				    dr->cookies, &ncookies,
1696				    (LDC_MAP_SHADOW |
1697				     LDC_MAP_DIRECT |
1698				     LDC_MAP_RW));
1699	if (IS_ERR(dring)) {
1700		err = PTR_ERR(dring);
1701		goto err_out;
1702	}
1703
1704	dr->base = dring;
1705	dr->entry_size = elen;
1706	dr->num_entries = VNET_TX_RING_SIZE;
1707	dr->prod = dr->cons = 0;
1708	port->start_cons  = true; /* need an initial trigger */
1709	dr->pending = VNET_TX_RING_SIZE;
1710	dr->ncookies = ncookies;
1711
1712	for (i = 0; i < VNET_TX_RING_SIZE; ++i) {
1713		struct vio_net_desc *d;
1714
1715		d = vio_dring_entry(dr, i);
1716		d->hdr.state = VIO_DESC_FREE;
1717	}
1718	return 0;
1719
1720err_out:
1721	vnet_port_free_tx_bufs(port);
1722
1723	return err;
1724}
1725
1726#ifdef CONFIG_NET_POLL_CONTROLLER
1727static void vnet_poll_controller(struct net_device *dev)
1728{
1729	struct vnet *vp = netdev_priv(dev);
1730	struct vnet_port *port;
1731	unsigned long flags;
1732
1733	spin_lock_irqsave(&vp->lock, flags);
1734	if (!list_empty(&vp->port_list)) {
1735		port = list_entry(vp->port_list.next, struct vnet_port, list);
1736		napi_schedule(&port->napi);
1737	}
1738	spin_unlock_irqrestore(&vp->lock, flags);
1739}
1740#endif
1741static LIST_HEAD(vnet_list);
1742static DEFINE_MUTEX(vnet_list_mutex);
1743
1744static const struct net_device_ops vnet_ops = {
1745	.ndo_open		= vnet_open,
1746	.ndo_stop		= vnet_close,
1747	.ndo_set_rx_mode	= vnet_set_rx_mode,
1748	.ndo_set_mac_address	= vnet_set_mac_addr,
1749	.ndo_validate_addr	= eth_validate_addr,
1750	.ndo_tx_timeout		= vnet_tx_timeout,
1751	.ndo_change_mtu		= vnet_change_mtu,
1752	.ndo_start_xmit		= vnet_start_xmit,
1753	.ndo_select_queue	= vnet_select_queue,
1754#ifdef CONFIG_NET_POLL_CONTROLLER
1755	.ndo_poll_controller	= vnet_poll_controller,
1756#endif
1757};
1758
1759static struct vnet *vnet_new(const u64 *local_mac)
1760{
1761	struct net_device *dev;
1762	struct vnet *vp;
1763	int err, i;
1764
1765	dev = alloc_etherdev_mqs(sizeof(*vp), VNET_MAX_TXQS, 1);
1766	if (!dev)
1767		return ERR_PTR(-ENOMEM);
1768	dev->needed_headroom = VNET_PACKET_SKIP + 8;
1769	dev->needed_tailroom = 8;
1770
1771	for (i = 0; i < ETH_ALEN; i++)
1772		dev->dev_addr[i] = (*local_mac >> (5 - i) * 8) & 0xff;
1773
1774	vp = netdev_priv(dev);
1775
1776	spin_lock_init(&vp->lock);
1777	vp->dev = dev;
1778
1779	INIT_LIST_HEAD(&vp->port_list);
1780	for (i = 0; i < VNET_PORT_HASH_SIZE; i++)
1781		INIT_HLIST_HEAD(&vp->port_hash[i]);
1782	INIT_LIST_HEAD(&vp->list);
1783	vp->local_mac = *local_mac;
1784
1785	dev->netdev_ops = &vnet_ops;
1786	dev->ethtool_ops = &vnet_ethtool_ops;
1787	dev->watchdog_timeo = VNET_TX_TIMEOUT;
1788
1789	dev->hw_features = NETIF_F_TSO | NETIF_F_GSO | NETIF_F_GSO_SOFTWARE |
1790			   NETIF_F_HW_CSUM | NETIF_F_SG;
1791	dev->features = dev->hw_features;
1792
1793	err = register_netdev(dev);
1794	if (err) {
1795		pr_err("Cannot register net device, aborting\n");
1796		goto err_out_free_dev;
1797	}
1798
1799	netdev_info(dev, "Sun LDOM vnet %pM\n", dev->dev_addr);
1800
1801	list_add(&vp->list, &vnet_list);
1802
1803	return vp;
1804
1805err_out_free_dev:
1806	free_netdev(dev);
1807
1808	return ERR_PTR(err);
1809}
1810
1811static struct vnet *vnet_find_or_create(const u64 *local_mac)
1812{
1813	struct vnet *iter, *vp;
1814
1815	mutex_lock(&vnet_list_mutex);
1816	vp = NULL;
1817	list_for_each_entry(iter, &vnet_list, list) {
1818		if (iter->local_mac == *local_mac) {
1819			vp = iter;
1820			break;
1821		}
1822	}
1823	if (!vp)
1824		vp = vnet_new(local_mac);
1825	mutex_unlock(&vnet_list_mutex);
1826
1827	return vp;
1828}
1829
1830static void vnet_cleanup(void)
1831{
1832	struct vnet *vp;
1833	struct net_device *dev;
1834
1835	mutex_lock(&vnet_list_mutex);
1836	while (!list_empty(&vnet_list)) {
1837		vp = list_first_entry(&vnet_list, struct vnet, list);
1838		list_del(&vp->list);
1839		dev = vp->dev;
1840		/* vio_unregister_driver() should have cleaned up port_list */
1841		BUG_ON(!list_empty(&vp->port_list));
1842		unregister_netdev(dev);
1843		free_netdev(dev);
1844	}
1845	mutex_unlock(&vnet_list_mutex);
1846}
1847
1848static const char *local_mac_prop = "local-mac-address";
1849
1850static struct vnet *vnet_find_parent(struct mdesc_handle *hp,
1851						u64 port_node)
1852{
1853	const u64 *local_mac = NULL;
1854	u64 a;
1855
1856	mdesc_for_each_arc(a, hp, port_node, MDESC_ARC_TYPE_BACK) {
1857		u64 target = mdesc_arc_target(hp, a);
1858		const char *name;
1859
1860		name = mdesc_get_property(hp, target, "name", NULL);
1861		if (!name || strcmp(name, "network"))
1862			continue;
1863
1864		local_mac = mdesc_get_property(hp, target,
1865					       local_mac_prop, NULL);
1866		if (local_mac)
1867			break;
1868	}
1869	if (!local_mac)
1870		return ERR_PTR(-ENODEV);
1871
1872	return vnet_find_or_create(local_mac);
1873}
1874
1875static struct ldc_channel_config vnet_ldc_cfg = {
1876	.event		= vnet_event,
1877	.mtu		= 64,
1878	.mode		= LDC_MODE_UNRELIABLE,
1879};
1880
1881static struct vio_driver_ops vnet_vio_ops = {
1882	.send_attr		= vnet_send_attr,
1883	.handle_attr		= vnet_handle_attr,
1884	.handshake_complete	= vnet_handshake_complete,
1885};
1886
1887static void print_version(void)
1888{
1889	printk_once(KERN_INFO "%s", version);
1890}
1891
1892const char *remote_macaddr_prop = "remote-mac-address";
1893
1894static void
1895vnet_port_add_txq(struct vnet_port *port)
1896{
1897	struct vnet *vp = port->vp;
1898	int n;
1899
1900	n = vp->nports++;
1901	n = n & (VNET_MAX_TXQS - 1);
1902	port->q_index = n;
1903	netif_tx_wake_queue(netdev_get_tx_queue(vp->dev, port->q_index));
1904}
1905
1906static void
1907vnet_port_rm_txq(struct vnet_port *port)
1908{
1909	port->vp->nports--;
1910	netif_tx_stop_queue(netdev_get_tx_queue(port->vp->dev, port->q_index));
1911}
1912
1913static int vnet_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1914{
1915	struct mdesc_handle *hp;
1916	struct vnet_port *port;
1917	unsigned long flags;
1918	struct vnet *vp;
1919	const u64 *rmac;
1920	int len, i, err, switch_port;
1921
1922	print_version();
1923
1924	hp = mdesc_grab();
1925
1926	vp = vnet_find_parent(hp, vdev->mp);
1927	if (IS_ERR(vp)) {
1928		pr_err("Cannot find port parent vnet\n");
1929		err = PTR_ERR(vp);
1930		goto err_out_put_mdesc;
1931	}
1932
1933	rmac = mdesc_get_property(hp, vdev->mp, remote_macaddr_prop, &len);
1934	err = -ENODEV;
1935	if (!rmac) {
1936		pr_err("Port lacks %s property\n", remote_macaddr_prop);
1937		goto err_out_put_mdesc;
1938	}
1939
1940	port = kzalloc(sizeof(*port), GFP_KERNEL);
1941	err = -ENOMEM;
1942	if (!port)
1943		goto err_out_put_mdesc;
1944
1945	for (i = 0; i < ETH_ALEN; i++)
1946		port->raddr[i] = (*rmac >> (5 - i) * 8) & 0xff;
1947
1948	port->vp = vp;
1949
1950	err = vio_driver_init(&port->vio, vdev, VDEV_NETWORK,
1951			      vnet_versions, ARRAY_SIZE(vnet_versions),
1952			      &vnet_vio_ops, vp->dev->name);
1953	if (err)
1954		goto err_out_free_port;
1955
1956	err = vio_ldc_alloc(&port->vio, &vnet_ldc_cfg, port);
1957	if (err)
1958		goto err_out_free_port;
1959
1960	netif_napi_add(port->vp->dev, &port->napi, vnet_poll, NAPI_POLL_WEIGHT);
1961
1962	INIT_HLIST_NODE(&port->hash);
1963	INIT_LIST_HEAD(&port->list);
1964
1965	switch_port = 0;
1966	if (mdesc_get_property(hp, vdev->mp, "switch-port", NULL) != NULL)
1967		switch_port = 1;
1968	port->switch_port = switch_port;
1969	port->tso = true;
1970	port->tsolen = 0;
1971
1972	spin_lock_irqsave(&vp->lock, flags);
1973	if (switch_port)
1974		list_add_rcu(&port->list, &vp->port_list);
1975	else
1976		list_add_tail_rcu(&port->list, &vp->port_list);
1977	hlist_add_head_rcu(&port->hash,
1978			   &vp->port_hash[vnet_hashfn(port->raddr)]);
1979	vnet_port_add_txq(port);
1980	spin_unlock_irqrestore(&vp->lock, flags);
1981
1982	dev_set_drvdata(&vdev->dev, port);
1983
1984	pr_info("%s: PORT ( remote-mac %pM%s )\n",
1985		vp->dev->name, port->raddr, switch_port ? " switch-port" : "");
1986
1987	setup_timer(&port->clean_timer, vnet_clean_timer_expire,
1988		    (unsigned long)port);
1989
1990	napi_enable(&port->napi);
1991	vio_port_up(&port->vio);
1992
1993	mdesc_release(hp);
1994
1995	return 0;
1996
1997err_out_free_port:
1998	kfree(port);
1999
2000err_out_put_mdesc:
2001	mdesc_release(hp);
2002	return err;
2003}
2004
2005static int vnet_port_remove(struct vio_dev *vdev)
2006{
2007	struct vnet_port *port = dev_get_drvdata(&vdev->dev);
2008
2009	if (port) {
2010
2011		del_timer_sync(&port->vio.timer);
2012
2013		napi_disable(&port->napi);
2014
2015		list_del_rcu(&port->list);
2016		hlist_del_rcu(&port->hash);
2017
2018		synchronize_rcu();
2019		del_timer_sync(&port->clean_timer);
2020		vnet_port_rm_txq(port);
2021		netif_napi_del(&port->napi);
2022		vnet_port_free_tx_bufs(port);
2023		vio_ldc_free(&port->vio);
2024
2025		dev_set_drvdata(&vdev->dev, NULL);
2026
2027		kfree(port);
2028
2029	}
2030	return 0;
2031}
2032
2033static const struct vio_device_id vnet_port_match[] = {
2034	{
2035		.type = "vnet-port",
2036	},
2037	{},
2038};
2039MODULE_DEVICE_TABLE(vio, vnet_port_match);
2040
2041static struct vio_driver vnet_port_driver = {
2042	.id_table	= vnet_port_match,
2043	.probe		= vnet_port_probe,
2044	.remove		= vnet_port_remove,
2045	.name		= "vnet_port",
2046};
2047
2048static int __init vnet_init(void)
2049{
2050	return vio_register_driver(&vnet_port_driver);
2051}
2052
2053static void __exit vnet_exit(void)
2054{
2055	vio_unregister_driver(&vnet_port_driver);
2056	vnet_cleanup();
2057}
2058
2059module_init(vnet_init);
2060module_exit(vnet_exit);
2061