Merge branch 'thinkpad-acpi' into release
[linux-2.6] / drivers / net / sunvnet.c
1 /* sunvnet.c: Sun LDOM Virtual Network Driver.
2  *
3  * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
4  */
5
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/types.h>
9 #include <linux/slab.h>
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/netdevice.h>
13 #include <linux/ethtool.h>
14 #include <linux/etherdevice.h>
15 #include <linux/mutex.h>
16
17 #include <asm/vio.h>
18 #include <asm/ldc.h>
19
20 #include "sunvnet.h"
21
22 #define DRV_MODULE_NAME         "sunvnet"
23 #define PFX DRV_MODULE_NAME     ": "
24 #define DRV_MODULE_VERSION      "1.0"
25 #define DRV_MODULE_RELDATE      "June 25, 2007"
26
27 static char version[] __devinitdata =
28         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
29 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
30 MODULE_DESCRIPTION("Sun LDOM virtual network driver");
31 MODULE_LICENSE("GPL");
32 MODULE_VERSION(DRV_MODULE_VERSION);
33
34 /* Ordered from largest major to lowest */
35 static struct vio_version vnet_versions[] = {
36         { .major = 1, .minor = 0 },
37 };
38
39 static inline u32 vnet_tx_dring_avail(struct vio_dring_state *dr)
40 {
41         return vio_dring_avail(dr, VNET_TX_RING_SIZE);
42 }
43
44 static int vnet_handle_unknown(struct vnet_port *port, void *arg)
45 {
46         struct vio_msg_tag *pkt = arg;
47
48         printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
49                pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
50         printk(KERN_ERR PFX "Resetting connection.\n");
51
52         ldc_disconnect(port->vio.lp);
53
54         return -ECONNRESET;
55 }
56
57 static int vnet_send_attr(struct vio_driver_state *vio)
58 {
59         struct vnet_port *port = to_vnet_port(vio);
60         struct net_device *dev = port->vp->dev;
61         struct vio_net_attr_info pkt;
62         int i;
63
64         memset(&pkt, 0, sizeof(pkt));
65         pkt.tag.type = VIO_TYPE_CTRL;
66         pkt.tag.stype = VIO_SUBTYPE_INFO;
67         pkt.tag.stype_env = VIO_ATTR_INFO;
68         pkt.tag.sid = vio_send_sid(vio);
69         pkt.xfer_mode = VIO_DRING_MODE;
70         pkt.addr_type = VNET_ADDR_ETHERMAC;
71         pkt.ack_freq = 0;
72         for (i = 0; i < 6; i++)
73                 pkt.addr |= (u64)dev->dev_addr[i] << ((5 - i) * 8);
74         pkt.mtu = ETH_FRAME_LEN;
75
76         viodbg(HS, "SEND NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
77                "ackfreq[%u] mtu[%llu]\n",
78                pkt.xfer_mode, pkt.addr_type,
79                (unsigned long long) pkt.addr,
80                pkt.ack_freq,
81                (unsigned long long) pkt.mtu);
82
83         return vio_ldc_send(vio, &pkt, sizeof(pkt));
84 }
85
86 static int handle_attr_info(struct vio_driver_state *vio,
87                             struct vio_net_attr_info *pkt)
88 {
89         viodbg(HS, "GOT NET ATTR INFO xmode[0x%x] atype[0x%x] addr[%llx] "
90                "ackfreq[%u] mtu[%llu]\n",
91                pkt->xfer_mode, pkt->addr_type,
92                (unsigned long long) pkt->addr,
93                pkt->ack_freq,
94                (unsigned long long) pkt->mtu);
95
96         pkt->tag.sid = vio_send_sid(vio);
97
98         if (pkt->xfer_mode != VIO_DRING_MODE ||
99             pkt->addr_type != VNET_ADDR_ETHERMAC ||
100             pkt->mtu != ETH_FRAME_LEN) {
101                 viodbg(HS, "SEND NET ATTR NACK\n");
102
103                 pkt->tag.stype = VIO_SUBTYPE_NACK;
104
105                 (void) vio_ldc_send(vio, pkt, sizeof(*pkt));
106
107                 return -ECONNRESET;
108         } else {
109                 viodbg(HS, "SEND NET ATTR ACK\n");
110
111                 pkt->tag.stype = VIO_SUBTYPE_ACK;
112
113                 return vio_ldc_send(vio, pkt, sizeof(*pkt));
114         }
115
116 }
117
118 static int handle_attr_ack(struct vio_driver_state *vio,
119                            struct vio_net_attr_info *pkt)
120 {
121         viodbg(HS, "GOT NET ATTR ACK\n");
122
123         return 0;
124 }
125
126 static int handle_attr_nack(struct vio_driver_state *vio,
127                             struct vio_net_attr_info *pkt)
128 {
129         viodbg(HS, "GOT NET ATTR NACK\n");
130
131         return -ECONNRESET;
132 }
133
134 static int vnet_handle_attr(struct vio_driver_state *vio, void *arg)
135 {
136         struct vio_net_attr_info *pkt = arg;
137
138         switch (pkt->tag.stype) {
139         case VIO_SUBTYPE_INFO:
140                 return handle_attr_info(vio, pkt);
141
142         case VIO_SUBTYPE_ACK:
143                 return handle_attr_ack(vio, pkt);
144
145         case VIO_SUBTYPE_NACK:
146                 return handle_attr_nack(vio, pkt);
147
148         default:
149                 return -ECONNRESET;
150         }
151 }
152
153 static void vnet_handshake_complete(struct vio_driver_state *vio)
154 {
155         struct vio_dring_state *dr;
156
157         dr = &vio->drings[VIO_DRIVER_RX_RING];
158         dr->snd_nxt = dr->rcv_nxt = 1;
159
160         dr = &vio->drings[VIO_DRIVER_TX_RING];
161         dr->snd_nxt = dr->rcv_nxt = 1;
162 }
163
164 /* The hypervisor interface that implements copying to/from imported
165  * memory from another domain requires that copies are done to 8-byte
166  * aligned buffers, and that the lengths of such copies are also 8-byte
167  * multiples.
168  *
169  * So we align skb->data to an 8-byte multiple and pad-out the data
170  * area so we can round the copy length up to the next multiple of
171  * 8 for the copy.
172  *
173  * The transmitter puts the actual start of the packet 6 bytes into
174  * the buffer it sends over, so that the IP headers after the ethernet
175  * header are aligned properly.  These 6 bytes are not in the descriptor
176  * length, they are simply implied.  This offset is represented using
177  * the VNET_PACKET_SKIP macro.
178  */
179 static struct sk_buff *alloc_and_align_skb(struct net_device *dev,
180                                            unsigned int len)
181 {
182         struct sk_buff *skb = netdev_alloc_skb(dev, len+VNET_PACKET_SKIP+8+8);
183         unsigned long addr, off;
184
185         if (unlikely(!skb))
186                 return NULL;
187
188         addr = (unsigned long) skb->data;
189         off = ((addr + 7UL) & ~7UL) - addr;
190         if (off)
191                 skb_reserve(skb, off);
192
193         return skb;
194 }
195
196 static int vnet_rx_one(struct vnet_port *port, unsigned int len,
197                        struct ldc_trans_cookie *cookies, int ncookies)
198 {
199         struct net_device *dev = port->vp->dev;
200         unsigned int copy_len;
201         struct sk_buff *skb;
202         int err;
203
204         err = -EMSGSIZE;
205         if (unlikely(len < ETH_ZLEN || len > ETH_FRAME_LEN)) {
206                 dev->stats.rx_length_errors++;
207                 goto out_dropped;
208         }
209
210         skb = alloc_and_align_skb(dev, len);
211         err = -ENOMEM;
212         if (unlikely(!skb)) {
213                 dev->stats.rx_missed_errors++;
214                 goto out_dropped;
215         }
216
217         copy_len = (len + VNET_PACKET_SKIP + 7U) & ~7U;
218         skb_put(skb, copy_len);
219         err = ldc_copy(port->vio.lp, LDC_COPY_IN,
220                        skb->data, copy_len, 0,
221                        cookies, ncookies);
222         if (unlikely(err < 0)) {
223                 dev->stats.rx_frame_errors++;
224                 goto out_free_skb;
225         }
226
227         skb_pull(skb, VNET_PACKET_SKIP);
228         skb_trim(skb, len);
229         skb->protocol = eth_type_trans(skb, dev);
230
231         dev->stats.rx_packets++;
232         dev->stats.rx_bytes += len;
233
234         netif_rx(skb);
235
236         return 0;
237
238 out_free_skb:
239         kfree_skb(skb);
240
241 out_dropped:
242         dev->stats.rx_dropped++;
243         return err;
244 }
245
246 static int vnet_send_ack(struct vnet_port *port, struct vio_dring_state *dr,
247                          u32 start, u32 end, u8 vio_dring_state)
248 {
249         struct vio_dring_data hdr = {
250                 .tag = {
251                         .type           = VIO_TYPE_DATA,
252                         .stype          = VIO_SUBTYPE_ACK,
253                         .stype_env      = VIO_DRING_DATA,
254                         .sid            = vio_send_sid(&port->vio),
255                 },
256                 .dring_ident            = dr->ident,
257                 .start_idx              = start,
258                 .end_idx                = end,
259                 .state                  = vio_dring_state,
260         };
261         int err, delay;
262
263         hdr.seq = dr->snd_nxt;
264         delay = 1;
265         do {
266                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
267                 if (err > 0) {
268                         dr->snd_nxt++;
269                         break;
270                 }
271                 udelay(delay);
272                 if ((delay <<= 1) > 128)
273                         delay = 128;
274         } while (err == -EAGAIN);
275
276         return err;
277 }
278
279 static u32 next_idx(u32 idx, struct vio_dring_state *dr)
280 {
281         if (++idx == dr->num_entries)
282                 idx = 0;
283         return idx;
284 }
285
286 static u32 prev_idx(u32 idx, struct vio_dring_state *dr)
287 {
288         if (idx == 0)
289                 idx = dr->num_entries - 1;
290         else
291                 idx--;
292
293         return idx;
294 }
295
296 static struct vio_net_desc *get_rx_desc(struct vnet_port *port,
297                                         struct vio_dring_state *dr,
298                                         u32 index)
299 {
300         struct vio_net_desc *desc = port->vio.desc_buf;
301         int err;
302
303         err = ldc_get_dring_entry(port->vio.lp, desc, dr->entry_size,
304                                   (index * dr->entry_size),
305                                   dr->cookies, dr->ncookies);
306         if (err < 0)
307                 return ERR_PTR(err);
308
309         return desc;
310 }
311
312 static int put_rx_desc(struct vnet_port *port,
313                        struct vio_dring_state *dr,
314                        struct vio_net_desc *desc,
315                        u32 index)
316 {
317         int err;
318
319         err = ldc_put_dring_entry(port->vio.lp, desc, dr->entry_size,
320                                   (index * dr->entry_size),
321                                   dr->cookies, dr->ncookies);
322         if (err < 0)
323                 return err;
324
325         return 0;
326 }
327
328 static int vnet_walk_rx_one(struct vnet_port *port,
329                             struct vio_dring_state *dr,
330                             u32 index, int *needs_ack)
331 {
332         struct vio_net_desc *desc = get_rx_desc(port, dr, index);
333         struct vio_driver_state *vio = &port->vio;
334         int err;
335
336         if (IS_ERR(desc))
337                 return PTR_ERR(desc);
338
339         viodbg(DATA, "vio_walk_rx_one desc[%02x:%02x:%08x:%08x:%llx:%llx]\n",
340                desc->hdr.state, desc->hdr.ack,
341                desc->size, desc->ncookies,
342                desc->cookies[0].cookie_addr,
343                desc->cookies[0].cookie_size);
344
345         if (desc->hdr.state != VIO_DESC_READY)
346                 return 1;
347         err = vnet_rx_one(port, desc->size, desc->cookies, desc->ncookies);
348         if (err == -ECONNRESET)
349                 return err;
350         desc->hdr.state = VIO_DESC_DONE;
351         err = put_rx_desc(port, dr, desc, index);
352         if (err < 0)
353                 return err;
354         *needs_ack = desc->hdr.ack;
355         return 0;
356 }
357
358 static int vnet_walk_rx(struct vnet_port *port, struct vio_dring_state *dr,
359                         u32 start, u32 end)
360 {
361         struct vio_driver_state *vio = &port->vio;
362         int ack_start = -1, ack_end = -1;
363
364         end = (end == (u32) -1) ? prev_idx(start, dr) : next_idx(end, dr);
365
366         viodbg(DATA, "vnet_walk_rx start[%08x] end[%08x]\n", start, end);
367
368         while (start != end) {
369                 int ack = 0, err = vnet_walk_rx_one(port, dr, start, &ack);
370                 if (err == -ECONNRESET)
371                         return err;
372                 if (err != 0)
373                         break;
374                 if (ack_start == -1)
375                         ack_start = start;
376                 ack_end = start;
377                 start = next_idx(start, dr);
378                 if (ack && start != end) {
379                         err = vnet_send_ack(port, dr, ack_start, ack_end,
380                                             VIO_DRING_ACTIVE);
381                         if (err == -ECONNRESET)
382                                 return err;
383                         ack_start = -1;
384                 }
385         }
386         if (unlikely(ack_start == -1))
387                 ack_start = ack_end = prev_idx(start, dr);
388         return vnet_send_ack(port, dr, ack_start, ack_end, VIO_DRING_STOPPED);
389 }
390
391 static int vnet_rx(struct vnet_port *port, void *msgbuf)
392 {
393         struct vio_dring_data *pkt = msgbuf;
394         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_RX_RING];
395         struct vio_driver_state *vio = &port->vio;
396
397         viodbg(DATA, "vnet_rx stype_env[%04x] seq[%016llx] rcv_nxt[%016llx]\n",
398                pkt->tag.stype_env, pkt->seq, dr->rcv_nxt);
399
400         if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
401                 return 0;
402         if (unlikely(pkt->seq != dr->rcv_nxt)) {
403                 printk(KERN_ERR PFX "RX out of sequence seq[0x%llx] "
404                        "rcv_nxt[0x%llx]\n", pkt->seq, dr->rcv_nxt);
405                 return 0;
406         }
407
408         dr->rcv_nxt++;
409
410         /* XXX Validate pkt->start_idx and pkt->end_idx XXX */
411
412         return vnet_walk_rx(port, dr, pkt->start_idx, pkt->end_idx);
413 }
414
415 static int idx_is_pending(struct vio_dring_state *dr, u32 end)
416 {
417         u32 idx = dr->cons;
418         int found = 0;
419
420         while (idx != dr->prod) {
421                 if (idx == end) {
422                         found = 1;
423                         break;
424                 }
425                 idx = next_idx(idx, dr);
426         }
427         return found;
428 }
429
430 static int vnet_ack(struct vnet_port *port, void *msgbuf)
431 {
432         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
433         struct vio_dring_data *pkt = msgbuf;
434         struct net_device *dev;
435         struct vnet *vp;
436         u32 end;
437
438         if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
439                 return 0;
440
441         end = pkt->end_idx;
442         if (unlikely(!idx_is_pending(dr, end)))
443                 return 0;
444
445         dr->cons = next_idx(end, dr);
446
447         vp = port->vp;
448         dev = vp->dev;
449         if (unlikely(netif_queue_stopped(dev) &&
450                      vnet_tx_dring_avail(dr) >= VNET_TX_WAKEUP_THRESH(dr)))
451                 return 1;
452
453         return 0;
454 }
455
456 static int vnet_nack(struct vnet_port *port, void *msgbuf)
457 {
458         /* XXX just reset or similar XXX */
459         return 0;
460 }
461
462 static int handle_mcast(struct vnet_port *port, void *msgbuf)
463 {
464         struct vio_net_mcast_info *pkt = msgbuf;
465
466         if (pkt->tag.stype != VIO_SUBTYPE_ACK)
467                 printk(KERN_ERR PFX "%s: Got unexpected MCAST reply "
468                        "[%02x:%02x:%04x:%08x]\n",
469                        port->vp->dev->name,
470                        pkt->tag.type,
471                        pkt->tag.stype,
472                        pkt->tag.stype_env,
473                        pkt->tag.sid);
474
475         return 0;
476 }
477
478 static void maybe_tx_wakeup(struct vnet *vp)
479 {
480         struct net_device *dev = vp->dev;
481
482         netif_tx_lock(dev);
483         if (likely(netif_queue_stopped(dev))) {
484                 struct vnet_port *port;
485                 int wake = 1;
486
487                 list_for_each_entry(port, &vp->port_list, list) {
488                         struct vio_dring_state *dr;
489
490                         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
491                         if (vnet_tx_dring_avail(dr) <
492                             VNET_TX_WAKEUP_THRESH(dr)) {
493                                 wake = 0;
494                                 break;
495                         }
496                 }
497                 if (wake)
498                         netif_wake_queue(dev);
499         }
500         netif_tx_unlock(dev);
501 }
502
503 static void vnet_event(void *arg, int event)
504 {
505         struct vnet_port *port = arg;
506         struct vio_driver_state *vio = &port->vio;
507         unsigned long flags;
508         int tx_wakeup, err;
509
510         spin_lock_irqsave(&vio->lock, flags);
511
512         if (unlikely(event == LDC_EVENT_RESET ||
513                      event == LDC_EVENT_UP)) {
514                 vio_link_state_change(vio, event);
515                 spin_unlock_irqrestore(&vio->lock, flags);
516
517                 if (event == LDC_EVENT_RESET)
518                         vio_port_up(vio);
519                 return;
520         }
521
522         if (unlikely(event != LDC_EVENT_DATA_READY)) {
523                 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
524                 spin_unlock_irqrestore(&vio->lock, flags);
525                 return;
526         }
527
528         tx_wakeup = err = 0;
529         while (1) {
530                 union {
531                         struct vio_msg_tag tag;
532                         u64 raw[8];
533                 } msgbuf;
534
535                 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
536                 if (unlikely(err < 0)) {
537                         if (err == -ECONNRESET)
538                                 vio_conn_reset(vio);
539                         break;
540                 }
541                 if (err == 0)
542                         break;
543                 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
544                        msgbuf.tag.type,
545                        msgbuf.tag.stype,
546                        msgbuf.tag.stype_env,
547                        msgbuf.tag.sid);
548                 err = vio_validate_sid(vio, &msgbuf.tag);
549                 if (err < 0)
550                         break;
551
552                 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
553                         if (msgbuf.tag.stype == VIO_SUBTYPE_INFO) {
554                                 err = vnet_rx(port, &msgbuf);
555                         } else if (msgbuf.tag.stype == VIO_SUBTYPE_ACK) {
556                                 err = vnet_ack(port, &msgbuf);
557                                 if (err > 0)
558                                         tx_wakeup |= err;
559                         } else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK) {
560                                 err = vnet_nack(port, &msgbuf);
561                         }
562                 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
563                         if (msgbuf.tag.stype_env == VNET_MCAST_INFO)
564                                 err = handle_mcast(port, &msgbuf);
565                         else
566                                 err = vio_control_pkt_engine(vio, &msgbuf);
567                         if (err)
568                                 break;
569                 } else {
570                         err = vnet_handle_unknown(port, &msgbuf);
571                 }
572                 if (err == -ECONNRESET)
573                         break;
574         }
575         spin_unlock(&vio->lock);
576         if (unlikely(tx_wakeup && err != -ECONNRESET))
577                 maybe_tx_wakeup(port->vp);
578         local_irq_restore(flags);
579 }
580
581 static int __vnet_tx_trigger(struct vnet_port *port)
582 {
583         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
584         struct vio_dring_data hdr = {
585                 .tag = {
586                         .type           = VIO_TYPE_DATA,
587                         .stype          = VIO_SUBTYPE_INFO,
588                         .stype_env      = VIO_DRING_DATA,
589                         .sid            = vio_send_sid(&port->vio),
590                 },
591                 .dring_ident            = dr->ident,
592                 .start_idx              = dr->prod,
593                 .end_idx                = (u32) -1,
594         };
595         int err, delay;
596
597         hdr.seq = dr->snd_nxt;
598         delay = 1;
599         do {
600                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
601                 if (err > 0) {
602                         dr->snd_nxt++;
603                         break;
604                 }
605                 udelay(delay);
606                 if ((delay <<= 1) > 128)
607                         delay = 128;
608         } while (err == -EAGAIN);
609
610         return err;
611 }
612
613 struct vnet_port *__tx_port_find(struct vnet *vp, struct sk_buff *skb)
614 {
615         unsigned int hash = vnet_hashfn(skb->data);
616         struct hlist_head *hp = &vp->port_hash[hash];
617         struct hlist_node *n;
618         struct vnet_port *port;
619
620         hlist_for_each_entry(port, n, hp, hash) {
621                 if (!compare_ether_addr(port->raddr, skb->data))
622                         return port;
623         }
624         port = NULL;
625         if (!list_empty(&vp->port_list))
626                 port = list_entry(vp->port_list.next, struct vnet_port, list);
627
628         return port;
629 }
630
631 struct vnet_port *tx_port_find(struct vnet *vp, struct sk_buff *skb)
632 {
633         struct vnet_port *ret;
634         unsigned long flags;
635
636         spin_lock_irqsave(&vp->lock, flags);
637         ret = __tx_port_find(vp, skb);
638         spin_unlock_irqrestore(&vp->lock, flags);
639
640         return ret;
641 }
642
643 static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
644 {
645         struct vnet *vp = netdev_priv(dev);
646         struct vnet_port *port = tx_port_find(vp, skb);
647         struct vio_dring_state *dr;
648         struct vio_net_desc *d;
649         unsigned long flags;
650         unsigned int len;
651         void *tx_buf;
652         int i, err;
653
654         if (unlikely(!port))
655                 goto out_dropped;
656
657         spin_lock_irqsave(&port->vio.lock, flags);
658
659         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
660         if (unlikely(vnet_tx_dring_avail(dr) < 2)) {
661                 if (!netif_queue_stopped(dev)) {
662                         netif_stop_queue(dev);
663
664                         /* This is a hard error, log it. */
665                         printk(KERN_ERR PFX "%s: BUG! Tx Ring full when "
666                                "queue awake!\n", dev->name);
667                         dev->stats.tx_errors++;
668                 }
669                 spin_unlock_irqrestore(&port->vio.lock, flags);
670                 return NETDEV_TX_BUSY;
671         }
672
673         d = vio_dring_cur(dr);
674
675         tx_buf = port->tx_bufs[dr->prod].buf;
676         skb_copy_from_linear_data(skb, tx_buf + VNET_PACKET_SKIP, skb->len);
677
678         len = skb->len;
679         if (len < ETH_ZLEN) {
680                 len = ETH_ZLEN;
681                 memset(tx_buf+VNET_PACKET_SKIP+skb->len, 0, len - skb->len);
682         }
683
684         d->hdr.ack = VIO_ACK_ENABLE;
685         d->size = len;
686         d->ncookies = port->tx_bufs[dr->prod].ncookies;
687         for (i = 0; i < d->ncookies; i++)
688                 d->cookies[i] = port->tx_bufs[dr->prod].cookies[i];
689
690         /* This has to be a non-SMP write barrier because we are writing
691          * to memory which is shared with the peer LDOM.
692          */
693         wmb();
694
695         d->hdr.state = VIO_DESC_READY;
696
697         err = __vnet_tx_trigger(port);
698         if (unlikely(err < 0)) {
699                 printk(KERN_INFO PFX "%s: TX trigger error %d\n",
700                        dev->name, err);
701                 d->hdr.state = VIO_DESC_FREE;
702                 dev->stats.tx_carrier_errors++;
703                 goto out_dropped_unlock;
704         }
705
706         dev->stats.tx_packets++;
707         dev->stats.tx_bytes += skb->len;
708
709         dr->prod = (dr->prod + 1) & (VNET_TX_RING_SIZE - 1);
710         if (unlikely(vnet_tx_dring_avail(dr) < 2)) {
711                 netif_stop_queue(dev);
712                 if (vnet_tx_dring_avail(dr) > VNET_TX_WAKEUP_THRESH(dr))
713                         netif_wake_queue(dev);
714         }
715
716         spin_unlock_irqrestore(&port->vio.lock, flags);
717
718         dev_kfree_skb(skb);
719
720         dev->trans_start = jiffies;
721         return NETDEV_TX_OK;
722
723 out_dropped_unlock:
724         spin_unlock_irqrestore(&port->vio.lock, flags);
725
726 out_dropped:
727         dev_kfree_skb(skb);
728         dev->stats.tx_dropped++;
729         return NETDEV_TX_OK;
730 }
731
732 static void vnet_tx_timeout(struct net_device *dev)
733 {
734         /* XXX Implement me XXX */
735 }
736
737 static int vnet_open(struct net_device *dev)
738 {
739         netif_carrier_on(dev);
740         netif_start_queue(dev);
741
742         return 0;
743 }
744
745 static int vnet_close(struct net_device *dev)
746 {
747         netif_stop_queue(dev);
748         netif_carrier_off(dev);
749
750         return 0;
751 }
752
753 static struct vnet_mcast_entry *__vnet_mc_find(struct vnet *vp, u8 *addr)
754 {
755         struct vnet_mcast_entry *m;
756
757         for (m = vp->mcast_list; m; m = m->next) {
758                 if (!memcmp(m->addr, addr, ETH_ALEN))
759                         return m;
760         }
761         return NULL;
762 }
763
764 static void __update_mc_list(struct vnet *vp, struct net_device *dev)
765 {
766         struct dev_addr_list *p;
767
768         for (p = dev->mc_list; p; p = p->next) {
769                 struct vnet_mcast_entry *m;
770
771                 m = __vnet_mc_find(vp, p->dmi_addr);
772                 if (m) {
773                         m->hit = 1;
774                         continue;
775                 }
776
777                 if (!m) {
778                         m = kzalloc(sizeof(*m), GFP_ATOMIC);
779                         if (!m)
780                                 continue;
781                         memcpy(m->addr, p->dmi_addr, ETH_ALEN);
782                         m->hit = 1;
783
784                         m->next = vp->mcast_list;
785                         vp->mcast_list = m;
786                 }
787         }
788 }
789
790 static void __send_mc_list(struct vnet *vp, struct vnet_port *port)
791 {
792         struct vio_net_mcast_info info;
793         struct vnet_mcast_entry *m, **pp;
794         int n_addrs;
795
796         memset(&info, 0, sizeof(info));
797
798         info.tag.type = VIO_TYPE_CTRL;
799         info.tag.stype = VIO_SUBTYPE_INFO;
800         info.tag.stype_env = VNET_MCAST_INFO;
801         info.tag.sid = vio_send_sid(&port->vio);
802         info.set = 1;
803
804         n_addrs = 0;
805         for (m = vp->mcast_list; m; m = m->next) {
806                 if (m->sent)
807                         continue;
808                 m->sent = 1;
809                 memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
810                        m->addr, ETH_ALEN);
811                 if (++n_addrs == VNET_NUM_MCAST) {
812                         info.count = n_addrs;
813
814                         (void) vio_ldc_send(&port->vio, &info,
815                                             sizeof(info));
816                         n_addrs = 0;
817                 }
818         }
819         if (n_addrs) {
820                 info.count = n_addrs;
821                 (void) vio_ldc_send(&port->vio, &info, sizeof(info));
822         }
823
824         info.set = 0;
825
826         n_addrs = 0;
827         pp = &vp->mcast_list;
828         while ((m = *pp) != NULL) {
829                 if (m->hit) {
830                         m->hit = 0;
831                         pp = &m->next;
832                         continue;
833                 }
834
835                 memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
836                        m->addr, ETH_ALEN);
837                 if (++n_addrs == VNET_NUM_MCAST) {
838                         info.count = n_addrs;
839                         (void) vio_ldc_send(&port->vio, &info,
840                                             sizeof(info));
841                         n_addrs = 0;
842                 }
843
844                 *pp = m->next;
845                 kfree(m);
846         }
847         if (n_addrs) {
848                 info.count = n_addrs;
849                 (void) vio_ldc_send(&port->vio, &info, sizeof(info));
850         }
851 }
852
853 static void vnet_set_rx_mode(struct net_device *dev)
854 {
855         struct vnet *vp = netdev_priv(dev);
856         struct vnet_port *port;
857         unsigned long flags;
858
859         spin_lock_irqsave(&vp->lock, flags);
860         if (!list_empty(&vp->port_list)) {
861                 port = list_entry(vp->port_list.next, struct vnet_port, list);
862
863                 if (port->switch_port) {
864                         __update_mc_list(vp, dev);
865                         __send_mc_list(vp, port);
866                 }
867         }
868         spin_unlock_irqrestore(&vp->lock, flags);
869 }
870
871 static int vnet_change_mtu(struct net_device *dev, int new_mtu)
872 {
873         if (new_mtu != ETH_DATA_LEN)
874                 return -EINVAL;
875
876         dev->mtu = new_mtu;
877         return 0;
878 }
879
880 static int vnet_set_mac_addr(struct net_device *dev, void *p)
881 {
882         return -EINVAL;
883 }
884
885 static void vnet_get_drvinfo(struct net_device *dev,
886                              struct ethtool_drvinfo *info)
887 {
888         strcpy(info->driver, DRV_MODULE_NAME);
889         strcpy(info->version, DRV_MODULE_VERSION);
890 }
891
892 static u32 vnet_get_msglevel(struct net_device *dev)
893 {
894         struct vnet *vp = netdev_priv(dev);
895         return vp->msg_enable;
896 }
897
898 static void vnet_set_msglevel(struct net_device *dev, u32 value)
899 {
900         struct vnet *vp = netdev_priv(dev);
901         vp->msg_enable = value;
902 }
903
904 static const struct ethtool_ops vnet_ethtool_ops = {
905         .get_drvinfo            = vnet_get_drvinfo,
906         .get_msglevel           = vnet_get_msglevel,
907         .set_msglevel           = vnet_set_msglevel,
908         .get_link               = ethtool_op_get_link,
909 };
910
911 static void vnet_port_free_tx_bufs(struct vnet_port *port)
912 {
913         struct vio_dring_state *dr;
914         int i;
915
916         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
917         if (dr->base) {
918                 ldc_free_exp_dring(port->vio.lp, dr->base,
919                                    (dr->entry_size * dr->num_entries),
920                                    dr->cookies, dr->ncookies);
921                 dr->base = NULL;
922                 dr->entry_size = 0;
923                 dr->num_entries = 0;
924                 dr->pending = 0;
925                 dr->ncookies = 0;
926         }
927
928         for (i = 0; i < VNET_TX_RING_SIZE; i++) {
929                 void *buf = port->tx_bufs[i].buf;
930
931                 if (!buf)
932                         continue;
933
934                 ldc_unmap(port->vio.lp,
935                           port->tx_bufs[i].cookies,
936                           port->tx_bufs[i].ncookies);
937
938                 kfree(buf);
939                 port->tx_bufs[i].buf = NULL;
940         }
941 }
942
943 static int __devinit vnet_port_alloc_tx_bufs(struct vnet_port *port)
944 {
945         struct vio_dring_state *dr;
946         unsigned long len;
947         int i, err, ncookies;
948         void *dring;
949
950         for (i = 0; i < VNET_TX_RING_SIZE; i++) {
951                 void *buf = kzalloc(ETH_FRAME_LEN + 8, GFP_KERNEL);
952                 int map_len = (ETH_FRAME_LEN + 7) & ~7;
953
954                 err = -ENOMEM;
955                 if (!buf) {
956                         printk(KERN_ERR "TX buffer allocation failure\n");
957                         goto err_out;
958                 }
959                 err = -EFAULT;
960                 if ((unsigned long)buf & (8UL - 1)) {
961                         printk(KERN_ERR "TX buffer misaligned\n");
962                         kfree(buf);
963                         goto err_out;
964                 }
965
966                 err = ldc_map_single(port->vio.lp, buf, map_len,
967                                      port->tx_bufs[i].cookies, 2,
968                                      (LDC_MAP_SHADOW |
969                                       LDC_MAP_DIRECT |
970                                       LDC_MAP_RW));
971                 if (err < 0) {
972                         kfree(buf);
973                         goto err_out;
974                 }
975                 port->tx_bufs[i].buf = buf;
976                 port->tx_bufs[i].ncookies = err;
977         }
978
979         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
980
981         len = (VNET_TX_RING_SIZE *
982                (sizeof(struct vio_net_desc) +
983                 (sizeof(struct ldc_trans_cookie) * 2)));
984
985         ncookies = VIO_MAX_RING_COOKIES;
986         dring = ldc_alloc_exp_dring(port->vio.lp, len,
987                                     dr->cookies, &ncookies,
988                                     (LDC_MAP_SHADOW |
989                                      LDC_MAP_DIRECT |
990                                      LDC_MAP_RW));
991         if (IS_ERR(dring)) {
992                 err = PTR_ERR(dring);
993                 goto err_out;
994         }
995
996         dr->base = dring;
997         dr->entry_size = (sizeof(struct vio_net_desc) +
998                           (sizeof(struct ldc_trans_cookie) * 2));
999         dr->num_entries = VNET_TX_RING_SIZE;
1000         dr->prod = dr->cons = 0;
1001         dr->pending = VNET_TX_RING_SIZE;
1002         dr->ncookies = ncookies;
1003
1004         return 0;
1005
1006 err_out:
1007         vnet_port_free_tx_bufs(port);
1008
1009         return err;
1010 }
1011
1012 static LIST_HEAD(vnet_list);
1013 static DEFINE_MUTEX(vnet_list_mutex);
1014
1015 static struct vnet * __devinit vnet_new(const u64 *local_mac)
1016 {
1017         struct net_device *dev;
1018         struct vnet *vp;
1019         int err, i;
1020
1021         dev = alloc_etherdev(sizeof(*vp));
1022         if (!dev) {
1023                 printk(KERN_ERR PFX "Etherdev alloc failed, aborting.\n");
1024                 return ERR_PTR(-ENOMEM);
1025         }
1026
1027         for (i = 0; i < ETH_ALEN; i++)
1028                 dev->dev_addr[i] = (*local_mac >> (5 - i) * 8) & 0xff;
1029
1030         memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
1031
1032         vp = netdev_priv(dev);
1033
1034         spin_lock_init(&vp->lock);
1035         vp->dev = dev;
1036
1037         INIT_LIST_HEAD(&vp->port_list);
1038         for (i = 0; i < VNET_PORT_HASH_SIZE; i++)
1039                 INIT_HLIST_HEAD(&vp->port_hash[i]);
1040         INIT_LIST_HEAD(&vp->list);
1041         vp->local_mac = *local_mac;
1042
1043         dev->open = vnet_open;
1044         dev->stop = vnet_close;
1045         dev->set_multicast_list = vnet_set_rx_mode;
1046         dev->set_mac_address = vnet_set_mac_addr;
1047         dev->tx_timeout = vnet_tx_timeout;
1048         dev->ethtool_ops = &vnet_ethtool_ops;
1049         dev->watchdog_timeo = VNET_TX_TIMEOUT;
1050         dev->change_mtu = vnet_change_mtu;
1051         dev->hard_start_xmit = vnet_start_xmit;
1052
1053         err = register_netdev(dev);
1054         if (err) {
1055                 printk(KERN_ERR PFX "Cannot register net device, "
1056                        "aborting.\n");
1057                 goto err_out_free_dev;
1058         }
1059
1060         printk(KERN_INFO "%s: Sun LDOM vnet ", dev->name);
1061
1062         for (i = 0; i < 6; i++)
1063                 printk("%2.2x%c", dev->dev_addr[i], i == 5 ? '\n' : ':');
1064
1065         list_add(&vp->list, &vnet_list);
1066
1067         return vp;
1068
1069 err_out_free_dev:
1070         free_netdev(dev);
1071
1072         return ERR_PTR(err);
1073 }
1074
1075 static struct vnet * __devinit vnet_find_or_create(const u64 *local_mac)
1076 {
1077         struct vnet *iter, *vp;
1078
1079         mutex_lock(&vnet_list_mutex);
1080         vp = NULL;
1081         list_for_each_entry(iter, &vnet_list, list) {
1082                 if (iter->local_mac == *local_mac) {
1083                         vp = iter;
1084                         break;
1085                 }
1086         }
1087         if (!vp)
1088                 vp = vnet_new(local_mac);
1089         mutex_unlock(&vnet_list_mutex);
1090
1091         return vp;
1092 }
1093
1094 static const char *local_mac_prop = "local-mac-address";
1095
1096 static struct vnet * __devinit vnet_find_parent(struct mdesc_handle *hp,
1097                                                 u64 port_node)
1098 {
1099         const u64 *local_mac = NULL;
1100         u64 a;
1101
1102         mdesc_for_each_arc(a, hp, port_node, MDESC_ARC_TYPE_BACK) {
1103                 u64 target = mdesc_arc_target(hp, a);
1104                 const char *name;
1105
1106                 name = mdesc_get_property(hp, target, "name", NULL);
1107                 if (!name || strcmp(name, "network"))
1108                         continue;
1109
1110                 local_mac = mdesc_get_property(hp, target,
1111                                                local_mac_prop, NULL);
1112                 if (local_mac)
1113                         break;
1114         }
1115         if (!local_mac)
1116                 return ERR_PTR(-ENODEV);
1117
1118         return vnet_find_or_create(local_mac);
1119 }
1120
1121 static struct ldc_channel_config vnet_ldc_cfg = {
1122         .event          = vnet_event,
1123         .mtu            = 64,
1124         .mode           = LDC_MODE_UNRELIABLE,
1125 };
1126
1127 static struct vio_driver_ops vnet_vio_ops = {
1128         .send_attr              = vnet_send_attr,
1129         .handle_attr            = vnet_handle_attr,
1130         .handshake_complete     = vnet_handshake_complete,
1131 };
1132
1133 static void __devinit print_version(void)
1134 {
1135         static int version_printed;
1136
1137         if (version_printed++ == 0)
1138                 printk(KERN_INFO "%s", version);
1139 }
1140
1141 const char *remote_macaddr_prop = "remote-mac-address";
1142
1143 static int __devinit vnet_port_probe(struct vio_dev *vdev,
1144                                      const struct vio_device_id *id)
1145 {
1146         struct mdesc_handle *hp;
1147         struct vnet_port *port;
1148         unsigned long flags;
1149         struct vnet *vp;
1150         const u64 *rmac;
1151         int len, i, err, switch_port;
1152
1153         print_version();
1154
1155         hp = mdesc_grab();
1156
1157         vp = vnet_find_parent(hp, vdev->mp);
1158         if (IS_ERR(vp)) {
1159                 printk(KERN_ERR PFX "Cannot find port parent vnet.\n");
1160                 err = PTR_ERR(vp);
1161                 goto err_out_put_mdesc;
1162         }
1163
1164         rmac = mdesc_get_property(hp, vdev->mp, remote_macaddr_prop, &len);
1165         err = -ENODEV;
1166         if (!rmac) {
1167                 printk(KERN_ERR PFX "Port lacks %s property.\n",
1168                        remote_macaddr_prop);
1169                 goto err_out_put_mdesc;
1170         }
1171
1172         port = kzalloc(sizeof(*port), GFP_KERNEL);
1173         err = -ENOMEM;
1174         if (!port) {
1175                 printk(KERN_ERR PFX "Cannot allocate vnet_port.\n");
1176                 goto err_out_put_mdesc;
1177         }
1178
1179         for (i = 0; i < ETH_ALEN; i++)
1180                 port->raddr[i] = (*rmac >> (5 - i) * 8) & 0xff;
1181
1182         port->vp = vp;
1183
1184         err = vio_driver_init(&port->vio, vdev, VDEV_NETWORK,
1185                               vnet_versions, ARRAY_SIZE(vnet_versions),
1186                               &vnet_vio_ops, vp->dev->name);
1187         if (err)
1188                 goto err_out_free_port;
1189
1190         err = vio_ldc_alloc(&port->vio, &vnet_ldc_cfg, port);
1191         if (err)
1192                 goto err_out_free_port;
1193
1194         err = vnet_port_alloc_tx_bufs(port);
1195         if (err)
1196                 goto err_out_free_ldc;
1197
1198         INIT_HLIST_NODE(&port->hash);
1199         INIT_LIST_HEAD(&port->list);
1200
1201         switch_port = 0;
1202         if (mdesc_get_property(hp, vdev->mp, "switch-port", NULL) != NULL)
1203                 switch_port = 1;
1204         port->switch_port = switch_port;
1205
1206         spin_lock_irqsave(&vp->lock, flags);
1207         if (switch_port)
1208                 list_add(&port->list, &vp->port_list);
1209         else
1210                 list_add_tail(&port->list, &vp->port_list);
1211         hlist_add_head(&port->hash, &vp->port_hash[vnet_hashfn(port->raddr)]);
1212         spin_unlock_irqrestore(&vp->lock, flags);
1213
1214         dev_set_drvdata(&vdev->dev, port);
1215
1216         printk(KERN_INFO "%s: PORT ( remote-mac %pM%s )\n",
1217                vp->dev->name, port->raddr,
1218                switch_port ? " switch-port" : "");
1219
1220         vio_port_up(&port->vio);
1221
1222         mdesc_release(hp);
1223
1224         return 0;
1225
1226 err_out_free_ldc:
1227         vio_ldc_free(&port->vio);
1228
1229 err_out_free_port:
1230         kfree(port);
1231
1232 err_out_put_mdesc:
1233         mdesc_release(hp);
1234         return err;
1235 }
1236
1237 static int vnet_port_remove(struct vio_dev *vdev)
1238 {
1239         struct vnet_port *port = dev_get_drvdata(&vdev->dev);
1240
1241         if (port) {
1242                 struct vnet *vp = port->vp;
1243                 unsigned long flags;
1244
1245                 del_timer_sync(&port->vio.timer);
1246
1247                 spin_lock_irqsave(&vp->lock, flags);
1248                 list_del(&port->list);
1249                 hlist_del(&port->hash);
1250                 spin_unlock_irqrestore(&vp->lock, flags);
1251
1252                 vnet_port_free_tx_bufs(port);
1253                 vio_ldc_free(&port->vio);
1254
1255                 dev_set_drvdata(&vdev->dev, NULL);
1256
1257                 kfree(port);
1258         }
1259         return 0;
1260 }
1261
1262 static const struct vio_device_id vnet_port_match[] = {
1263         {
1264                 .type = "vnet-port",
1265         },
1266         {},
1267 };
1268 MODULE_DEVICE_TABLE(vio, vnet_port_match);
1269
1270 static struct vio_driver vnet_port_driver = {
1271         .id_table       = vnet_port_match,
1272         .probe          = vnet_port_probe,
1273         .remove         = vnet_port_remove,
1274         .driver         = {
1275                 .name   = "vnet_port",
1276                 .owner  = THIS_MODULE,
1277         }
1278 };
1279
1280 static int __init vnet_init(void)
1281 {
1282         return vio_register_driver(&vnet_port_driver);
1283 }
1284
1285 static void __exit vnet_exit(void)
1286 {
1287         vio_unregister_driver(&vnet_port_driver);
1288 }
1289
1290 module_init(vnet_init);
1291 module_exit(vnet_exit);