?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
irqchip/s3c24xx: Mark init_eint as __maybe_unused
[linux/fpc-iii.git] / drivers / net / xen-netfront.c
blobd6abf191122a3260cbd97f5c1a2dbd1c2cb5c5e2
1 /*
2 * Virtual network driver for conversing with remote driver backends.
3 *
4 * Copyright (c) 2002-2005, K A Fraser
5 * Copyright (c) 2005, XenSource Ltd
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version 2
9 * as published by the Free Software Foundation; or, when distributed
10 * separately from the Linux kernel or incorporated into other
11 * software packages, subject to the following license:
12 *
13 * Permission is hereby granted, free of charge, to any person obtaining a copy
14 * of this source file (the "Software"), to deal in the Software without
15 * restriction, including without limitation the rights to use, copy, modify,
16 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
17 * and to permit persons to whom the Software is furnished to do so, subject to
18 * the following conditions:
19 *
20 * The above copyright notice and this permission notice shall be included in
21 * all copies or substantial portions of the Software.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
25 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
26 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
27 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
28 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
29 * IN THE SOFTWARE.
30 */
31
32 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
33
34 #include <linux/module.h>
35 #include <linux/kernel.h>
36 #include <linux/netdevice.h>
37 #include <linux/etherdevice.h>
38 #include <linux/skbuff.h>
39 #include <linux/ethtool.h>
40 #include <linux/if_ether.h>
41 #include <net/tcp.h>
42 #include <linux/udp.h>
43 #include <linux/moduleparam.h>
44 #include <linux/mm.h>
45 #include <linux/slab.h>
46 #include <net/ip.h>
47
48 #include <xen/xen.h>
49 #include <xen/xenbus.h>
50 #include <xen/events.h>
51 #include <xen/page.h>
52 #include <xen/platform_pci.h>
53 #include <xen/grant_table.h>
54
55 #include <xen/interface/io/netif.h>
56 #include <xen/interface/memory.h>
57 #include <xen/interface/grant_table.h>
58
59 /* Module parameters */
60 static unsigned int xennet_max_queues;
61 module_param_named(max_queues, xennet_max_queues, uint, 0644);
62 MODULE_PARM_DESC(max_queues,
63 "Maximum number of queues per virtual interface");
64
65 static const struct ethtool_ops xennet_ethtool_ops;
66
67 struct netfront_cb {
68 int pull_to;
69 };
70
71 #define NETFRONT_SKB_CB(skb) ((struct netfront_cb *)((skb)->cb))
72
73 #define RX_COPY_THRESHOLD 256
74
75 #define GRANT_INVALID_REF 0
76
77 #define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, XEN_PAGE_SIZE)
78 #define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, XEN_PAGE_SIZE)
79
80 /* Minimum number of Rx slots (includes slot for GSO metadata). */
81 #define NET_RX_SLOTS_MIN (XEN_NETIF_NR_SLOTS_MIN + 1)
82
83 /* Queue name is interface name with "-qNNN" appended */
84 #define QUEUE_NAME_SIZE (IFNAMSIZ + 6)
85
86 /* IRQ name is queue name with "-tx" or "-rx" appended */
87 #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3)
88
89 struct netfront_stats {
90 u64 packets;
91 u64 bytes;
92 struct u64_stats_sync syncp;
93 };
94
95 struct netfront_info;
96
97 struct netfront_queue {
98 unsigned int id; /* Queue ID, 0-based */
99 char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */
100 struct netfront_info *info;
101
102 struct napi_struct napi;
103
104 /* Split event channels support, tx_* == rx_* when using
105 * single event channel.
106 */
107 unsigned int tx_evtchn, rx_evtchn;
108 unsigned int tx_irq, rx_irq;
109 /* Only used when split event channels support is enabled */
110 char tx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-tx */
111 char rx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-rx */
112
113 spinlock_t tx_lock;
114 struct xen_netif_tx_front_ring tx;
115 int tx_ring_ref;
116
117 /*
118 * {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries
119 * are linked from tx_skb_freelist through skb_entry.link.
120 *
121 * NB. Freelist index entries are always going to be less than
122 * PAGE_OFFSET, whereas pointers to skbs will always be equal or
123 * greater than PAGE_OFFSET: we use this property to distinguish
124 * them.
125 */
126 union skb_entry {
127 struct sk_buff *skb;
128 unsigned long link;
129 } tx_skbs[NET_TX_RING_SIZE];
130 grant_ref_t gref_tx_head;
131 grant_ref_t grant_tx_ref[NET_TX_RING_SIZE];
132 struct page *grant_tx_page[NET_TX_RING_SIZE];
133 unsigned tx_skb_freelist;
134
135 spinlock_t rx_lock ____cacheline_aligned_in_smp;
136 struct xen_netif_rx_front_ring rx;
137 int rx_ring_ref;
138
139 struct timer_list rx_refill_timer;
140
141 struct sk_buff *rx_skbs[NET_RX_RING_SIZE];
142 grant_ref_t gref_rx_head;
143 grant_ref_t grant_rx_ref[NET_RX_RING_SIZE];
144 };
145
146 struct netfront_info {
147 struct list_head list;
148 struct net_device *netdev;
149
150 struct xenbus_device *xbdev;
151
152 /* Multi-queue support */
153 struct netfront_queue *queues;
154
155 /* Statistics */
156 struct netfront_stats __percpu *rx_stats;
157 struct netfront_stats __percpu *tx_stats;
158
159 atomic_t rx_gso_checksum_fixup;
160 };
161
162 struct netfront_rx_info {
163 struct xen_netif_rx_response rx;
164 struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
165 };
166
167 static void skb_entry_set_link(union skb_entry *list, unsigned short id)
168 {
169 list->link = id;
170 }
171
172 static int skb_entry_is_link(const union skb_entry *list)
173 {
174 BUILD_BUG_ON(sizeof(list->skb) != sizeof(list->link));
175 return (unsigned long)list->skb < PAGE_OFFSET;
176 }
177
178 /*
179 * Access macros for acquiring freeing slots in tx_skbs[].
180 */
181
182 static void add_id_to_freelist(unsigned *head, union skb_entry *list,
183 unsigned short id)
184 {
185 skb_entry_set_link(&list[id], *head);
186 *head = id;
187 }
188
189 static unsigned short get_id_from_freelist(unsigned *head,
190 union skb_entry *list)
191 {
192 unsigned int id = *head;
193 *head = list[id].link;
194 return id;
195 }
196
197 static int xennet_rxidx(RING_IDX idx)
198 {
199 return idx & (NET_RX_RING_SIZE - 1);
200 }
201
202 static struct sk_buff *xennet_get_rx_skb(struct netfront_queue *queue,
203 RING_IDX ri)
204 {
205 int i = xennet_rxidx(ri);
206 struct sk_buff *skb = queue->rx_skbs[i];
207 queue->rx_skbs[i] = NULL;
208 return skb;
209 }
210
211 static grant_ref_t xennet_get_rx_ref(struct netfront_queue *queue,
212 RING_IDX ri)
213 {
214 int i = xennet_rxidx(ri);
215 grant_ref_t ref = queue->grant_rx_ref[i];
216 queue->grant_rx_ref[i] = GRANT_INVALID_REF;
217 return ref;
218 }
219
220 #ifdef CONFIG_SYSFS
221 static const struct attribute_group xennet_dev_group;
222 #endif
223
224 static bool xennet_can_sg(struct net_device *dev)
225 {
226 return dev->features & NETIF_F_SG;
227 }
228
229
230 static void rx_refill_timeout(unsigned long data)
231 {
232 struct netfront_queue *queue = (struct netfront_queue *)data;
233 napi_schedule(&queue->napi);
234 }
235
236 static int netfront_tx_slot_available(struct netfront_queue *queue)
237 {
238 return (queue->tx.req_prod_pvt - queue->tx.rsp_cons) <
239 (NET_TX_RING_SIZE - MAX_SKB_FRAGS - 2);
240 }
241
242 static void xennet_maybe_wake_tx(struct netfront_queue *queue)
243 {
244 struct net_device *dev = queue->info->netdev;
245 struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, queue->id);
246
247 if (unlikely(netif_tx_queue_stopped(dev_queue)) &&
248 netfront_tx_slot_available(queue) &&
249 likely(netif_running(dev)))
250 netif_tx_wake_queue(netdev_get_tx_queue(dev, queue->id));
251 }
252
253
254 static struct sk_buff *xennet_alloc_one_rx_buffer(struct netfront_queue *queue)
255 {
256 struct sk_buff *skb;
257 struct page *page;
258
259 skb = __netdev_alloc_skb(queue->info->netdev,
260 RX_COPY_THRESHOLD + NET_IP_ALIGN,
261 GFP_ATOMIC | __GFP_NOWARN);
262 if (unlikely(!skb))
263 return NULL;
264
265 page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
266 if (!page) {
267 kfree_skb(skb);
268 return NULL;
269 }
270 skb_add_rx_frag(skb, 0, page, 0, 0, PAGE_SIZE);
271
272 /* Align ip header to a 16 bytes boundary */
273 skb_reserve(skb, NET_IP_ALIGN);
274 skb->dev = queue->info->netdev;
275
276 return skb;
277 }
278
279
280 static void xennet_alloc_rx_buffers(struct netfront_queue *queue)
281 {
282 RING_IDX req_prod = queue->rx.req_prod_pvt;
283 int notify;
284
285 if (unlikely(!netif_carrier_ok(queue->info->netdev)))
286 return;
287
288 for (req_prod = queue->rx.req_prod_pvt;
289 req_prod - queue->rx.rsp_cons < NET_RX_RING_SIZE;
290 req_prod++) {
291 struct sk_buff *skb;
292 unsigned short id;
293 grant_ref_t ref;
294 struct page *page;
295 struct xen_netif_rx_request *req;
296
297 skb = xennet_alloc_one_rx_buffer(queue);
298 if (!skb)
299 break;
300
301 id = xennet_rxidx(req_prod);
302
303 BUG_ON(queue->rx_skbs[id]);
304 queue->rx_skbs[id] = skb;
305
306 ref = gnttab_claim_grant_reference(&queue->gref_rx_head);
307 BUG_ON((signed short)ref < 0);
308 queue->grant_rx_ref[id] = ref;
309
310 page = skb_frag_page(&skb_shinfo(skb)->frags[0]);
311
312 req = RING_GET_REQUEST(&queue->rx, req_prod);
313 gnttab_page_grant_foreign_access_ref_one(ref,
314 queue->info->xbdev->otherend_id,
315 page,
316 0);
317 req->id = id;
318 req->gref = ref;
319 }
320
321 queue->rx.req_prod_pvt = req_prod;
322
323 /* Not enough requests? Try again later. */
324 if (req_prod - queue->rx.rsp_cons < NET_RX_SLOTS_MIN) {
325 mod_timer(&queue->rx_refill_timer, jiffies + (HZ/10));
326 return;
327 }
328
329 wmb(); /* barrier so backend seens requests */
330
331 RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->rx, notify);
332 if (notify)
333 notify_remote_via_irq(queue->rx_irq);
334 }
335
336 static int xennet_open(struct net_device *dev)
337 {
338 struct netfront_info *np = netdev_priv(dev);
339 unsigned int num_queues = dev->real_num_tx_queues;
340 unsigned int i = 0;
341 struct netfront_queue *queue = NULL;
342
343 for (i = 0; i < num_queues; ++i) {
344 queue = &np->queues[i];
345 napi_enable(&queue->napi);
346
347 spin_lock_bh(&queue->rx_lock);
348 if (netif_carrier_ok(dev)) {
349 xennet_alloc_rx_buffers(queue);
350 queue->rx.sring->rsp_event = queue->rx.rsp_cons + 1;
351 if (RING_HAS_UNCONSUMED_RESPONSES(&queue->rx))
352 napi_schedule(&queue->napi);
353 }
354 spin_unlock_bh(&queue->rx_lock);
355 }
356
357 netif_tx_start_all_queues(dev);
358
359 return 0;
360 }
361
362 static void xennet_tx_buf_gc(struct netfront_queue *queue)
363 {
364 RING_IDX cons, prod;
365 unsigned short id;
366 struct sk_buff *skb;
367
368 BUG_ON(!netif_carrier_ok(queue->info->netdev));
369
370 do {
371 prod = queue->tx.sring->rsp_prod;
372 rmb(); /* Ensure we see responses up to 'rp'. */
373
374 for (cons = queue->tx.rsp_cons; cons != prod; cons++) {
375 struct xen_netif_tx_response *txrsp;
376
377 txrsp = RING_GET_RESPONSE(&queue->tx, cons);
378 if (txrsp->status == XEN_NETIF_RSP_NULL)
379 continue;
380
381 id = txrsp->id;
382 skb = queue->tx_skbs[id].skb;
383 if (unlikely(gnttab_query_foreign_access(
384 queue->grant_tx_ref[id]) != 0)) {
385 pr_alert("%s: warning -- grant still in use by backend domain\n",
386 __func__);
387 BUG();
388 }
389 gnttab_end_foreign_access_ref(
390 queue->grant_tx_ref[id], GNTMAP_readonly);
391 gnttab_release_grant_reference(
392 &queue->gref_tx_head, queue->grant_tx_ref[id]);
393 queue->grant_tx_ref[id] = GRANT_INVALID_REF;
394 queue->grant_tx_page[id] = NULL;
395 add_id_to_freelist(&queue->tx_skb_freelist, queue->tx_skbs, id);
396 dev_kfree_skb_irq(skb);
397 }
398
399 queue->tx.rsp_cons = prod;
400
401 /*
402 * Set a new event, then check for race with update of tx_cons.
403 * Note that it is essential to schedule a callback, no matter
404 * how few buffers are pending. Even if there is space in the
405 * transmit ring, higher layers may be blocked because too much
406 * data is outstanding: in such cases notification from Xen is
407 * likely to be the only kick that we'll get.
408 */
409 queue->tx.sring->rsp_event =
410 prod + ((queue->tx.sring->req_prod - prod) >> 1) + 1;
411 mb(); /* update shared area */
412 } while ((cons == prod) && (prod != queue->tx.sring->rsp_prod));
413
414 xennet_maybe_wake_tx(queue);
415 }
416
417 struct xennet_gnttab_make_txreq {
418 struct netfront_queue *queue;
419 struct sk_buff *skb;
420 struct page *page;
421 struct xen_netif_tx_request *tx; /* Last request */
422 unsigned int size;
423 };
424
425 static void xennet_tx_setup_grant(unsigned long gfn, unsigned int offset,
426 unsigned int len, void *data)
427 {
428 struct xennet_gnttab_make_txreq *info = data;
429 unsigned int id;
430 struct xen_netif_tx_request *tx;
431 grant_ref_t ref;
432 /* convenient aliases */
433 struct page *page = info->page;
434 struct netfront_queue *queue = info->queue;
435 struct sk_buff *skb = info->skb;
436
437 id = get_id_from_freelist(&queue->tx_skb_freelist, queue->tx_skbs);
438 tx = RING_GET_REQUEST(&queue->tx, queue->tx.req_prod_pvt++);
439 ref = gnttab_claim_grant_reference(&queue->gref_tx_head);
440 BUG_ON((signed short)ref < 0);
441
442 gnttab_grant_foreign_access_ref(ref, queue->info->xbdev->otherend_id,
443 gfn, GNTMAP_readonly);
444
445 queue->tx_skbs[id].skb = skb;
446 queue->grant_tx_page[id] = page;
447 queue->grant_tx_ref[id] = ref;
448
449 tx->id = id;
450 tx->gref = ref;
451 tx->offset = offset;
452 tx->size = len;
453 tx->flags = 0;
454
455 info->tx = tx;
456 info->size += tx->size;
457 }
458
459 static struct xen_netif_tx_request *xennet_make_first_txreq(
460 struct netfront_queue *queue, struct sk_buff *skb,
461 struct page *page, unsigned int offset, unsigned int len)
462 {
463 struct xennet_gnttab_make_txreq info = {
464 .queue = queue,
465 .skb = skb,
466 .page = page,
467 .size = 0,
468 };
469
470 gnttab_for_one_grant(page, offset, len, xennet_tx_setup_grant, &info);
471
472 return info.tx;
473 }
474
475 static void xennet_make_one_txreq(unsigned long gfn, unsigned int offset,
476 unsigned int len, void *data)
477 {
478 struct xennet_gnttab_make_txreq *info = data;
479
480 info->tx->flags |= XEN_NETTXF_more_data;
481 skb_get(info->skb);
482 xennet_tx_setup_grant(gfn, offset, len, data);
483 }
484
485 static struct xen_netif_tx_request *xennet_make_txreqs(
486 struct netfront_queue *queue, struct xen_netif_tx_request *tx,
487 struct sk_buff *skb, struct page *page,
488 unsigned int offset, unsigned int len)
489 {
490 struct xennet_gnttab_make_txreq info = {
491 .queue = queue,
492 .skb = skb,
493 .tx = tx,
494 };
495
496 /* Skip unused frames from start of page */
497 page += offset >> PAGE_SHIFT;
498 offset &= ~PAGE_MASK;
499
500 while (len) {
501 info.page = page;
502 info.size = 0;
503
504 gnttab_foreach_grant_in_range(page, offset, len,
505 xennet_make_one_txreq,
506 &info);
507
508 page++;
509 offset = 0;
510 len -= info.size;
511 }
512
513 return info.tx;
514 }
515
516 /*
517 * Count how many ring slots are required to send this skb. Each frag
518 * might be a compound page.
519 */
520 static int xennet_count_skb_slots(struct sk_buff *skb)
521 {
522 int i, frags = skb_shinfo(skb)->nr_frags;
523 int slots;
524
525 slots = gnttab_count_grant(offset_in_page(skb->data),
526 skb_headlen(skb));
527
528 for (i = 0; i < frags; i++) {
529 skb_frag_t *frag = skb_shinfo(skb)->frags + i;
530 unsigned long size = skb_frag_size(frag);
531 unsigned long offset = frag->page_offset;
532
533 /* Skip unused frames from start of page */
534 offset &= ~PAGE_MASK;
535
536 slots += gnttab_count_grant(offset, size);
537 }
538
539 return slots;
540 }
541
542 static u16 xennet_select_queue(struct net_device *dev, struct sk_buff *skb,
543 void *accel_priv, select_queue_fallback_t fallback)
544 {
545 unsigned int num_queues = dev->real_num_tx_queues;
546 u32 hash;
547 u16 queue_idx;
548
549 /* First, check if there is only one queue */
550 if (num_queues == 1) {
551 queue_idx = 0;
552 } else {
553 hash = skb_get_hash(skb);
554 queue_idx = hash % num_queues;
555 }
556
557 return queue_idx;
558 }
559
560 #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1)
561
562 static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev)
563 {
564 struct netfront_info *np = netdev_priv(dev);
565 struct netfront_stats *tx_stats = this_cpu_ptr(np->tx_stats);
566 struct xen_netif_tx_request *tx, *first_tx;
567 unsigned int i;
568 int notify;
569 int slots;
570 struct page *page;
571 unsigned int offset;
572 unsigned int len;
573 unsigned long flags;
574 struct netfront_queue *queue = NULL;
575 unsigned int num_queues = dev->real_num_tx_queues;
576 u16 queue_index;
577
578 /* Drop the packet if no queues are set up */
579 if (num_queues < 1)
580 goto drop;
581 /* Determine which queue to transmit this SKB on */
582 queue_index = skb_get_queue_mapping(skb);
583 queue = &np->queues[queue_index];
584
585 /* If skb->len is too big for wire format, drop skb and alert
586 * user about misconfiguration.
587 */
588 if (unlikely(skb->len > XEN_NETIF_MAX_TX_SIZE)) {
589 net_alert_ratelimited(
590 "xennet: skb->len = %u, too big for wire format\n",
591 skb->len);
592 goto drop;
593 }
594
595 slots = xennet_count_skb_slots(skb);
596 if (unlikely(slots > MAX_XEN_SKB_FRAGS + 1)) {
597 net_dbg_ratelimited("xennet: skb rides the rocket: %d slots, %d bytes\n",
598 slots, skb->len);
599 if (skb_linearize(skb))
600 goto drop;
601 }
602
603 page = virt_to_page(skb->data);
604 offset = offset_in_page(skb->data);
605 len = skb_headlen(skb);
606
607 spin_lock_irqsave(&queue->tx_lock, flags);
608
609 if (unlikely(!netif_carrier_ok(dev) ||
610 (slots > 1 && !xennet_can_sg(dev)) ||
611 netif_needs_gso(skb, netif_skb_features(skb)))) {
612 spin_unlock_irqrestore(&queue->tx_lock, flags);
613 goto drop;
614 }
615
616 /* First request for the linear area. */
617 first_tx = tx = xennet_make_first_txreq(queue, skb,
618 page, offset, len);
619 offset += tx->size;
620 if (offset == PAGE_SIZE) {
621 page++;
622 offset = 0;
623 }
624 len -= tx->size;
625
626 if (skb->ip_summed == CHECKSUM_PARTIAL)
627 /* local packet? */
628 tx->flags |= XEN_NETTXF_csum_blank | XEN_NETTXF_data_validated;
629 else if (skb->ip_summed == CHECKSUM_UNNECESSARY)
630 /* remote but checksummed. */
631 tx->flags |= XEN_NETTXF_data_validated;
632
633 /* Optional extra info after the first request. */
634 if (skb_shinfo(skb)->gso_size) {
635 struct xen_netif_extra_info *gso;
636
637 gso = (struct xen_netif_extra_info *)
638 RING_GET_REQUEST(&queue->tx, queue->tx.req_prod_pvt++);
639
640 tx->flags |= XEN_NETTXF_extra_info;
641
642 gso->u.gso.size = skb_shinfo(skb)->gso_size;
643 gso->u.gso.type = (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) ?
644 XEN_NETIF_GSO_TYPE_TCPV6 :
645 XEN_NETIF_GSO_TYPE_TCPV4;
646 gso->u.gso.pad = 0;
647 gso->u.gso.features = 0;
648
649 gso->type = XEN_NETIF_EXTRA_TYPE_GSO;
650 gso->flags = 0;
651 }
652
653 /* Requests for the rest of the linear area. */
654 tx = xennet_make_txreqs(queue, tx, skb, page, offset, len);
655
656 /* Requests for all the frags. */
657 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
658 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
659 tx = xennet_make_txreqs(queue, tx, skb,
660 skb_frag_page(frag), frag->page_offset,
661 skb_frag_size(frag));
662 }
663
664 /* First request has the packet length. */
665 first_tx->size = skb->len;
666
667 RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->tx, notify);
668 if (notify)
669 notify_remote_via_irq(queue->tx_irq);
670
671 u64_stats_update_begin(&tx_stats->syncp);
672 tx_stats->bytes += skb->len;
673 tx_stats->packets++;
674 u64_stats_update_end(&tx_stats->syncp);
675
676 /* Note: It is not safe to access skb after xennet_tx_buf_gc()! */
677 xennet_tx_buf_gc(queue);
678
679 if (!netfront_tx_slot_available(queue))
680 netif_tx_stop_queue(netdev_get_tx_queue(dev, queue->id));
681
682 spin_unlock_irqrestore(&queue->tx_lock, flags);
683
684 return NETDEV_TX_OK;
685
686 drop:
687 dev->stats.tx_dropped++;
688 dev_kfree_skb_any(skb);
689 return NETDEV_TX_OK;
690 }
691
692 static int xennet_close(struct net_device *dev)
693 {
694 struct netfront_info *np = netdev_priv(dev);
695 unsigned int num_queues = dev->real_num_tx_queues;
696 unsigned int i;
697 struct netfront_queue *queue;
698 netif_tx_stop_all_queues(np->netdev);
699 for (i = 0; i < num_queues; ++i) {
700 queue = &np->queues[i];
701 napi_disable(&queue->napi);
702 }
703 return 0;
704 }
705
706 static void xennet_move_rx_slot(struct netfront_queue *queue, struct sk_buff *skb,
707 grant_ref_t ref)
708 {
709 int new = xennet_rxidx(queue->rx.req_prod_pvt);
710
711 BUG_ON(queue->rx_skbs[new]);
712 queue->rx_skbs[new] = skb;
713 queue->grant_rx_ref[new] = ref;
714 RING_GET_REQUEST(&queue->rx, queue->rx.req_prod_pvt)->id = new;
715 RING_GET_REQUEST(&queue->rx, queue->rx.req_prod_pvt)->gref = ref;
716 queue->rx.req_prod_pvt++;
717 }
718
719 static int xennet_get_extras(struct netfront_queue *queue,
720 struct xen_netif_extra_info *extras,
721 RING_IDX rp)
722
723 {
724 struct xen_netif_extra_info *extra;
725 struct device *dev = &queue->info->netdev->dev;
726 RING_IDX cons = queue->rx.rsp_cons;
727 int err = 0;
728
729 do {
730 struct sk_buff *skb;
731 grant_ref_t ref;
732
733 if (unlikely(cons + 1 == rp)) {
734 if (net_ratelimit())
735 dev_warn(dev, "Missing extra info\n");
736 err = -EBADR;
737 break;
738 }
739
740 extra = (struct xen_netif_extra_info *)
741 RING_GET_RESPONSE(&queue->rx, ++cons);
742
743 if (unlikely(!extra->type ||
744 extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
745 if (net_ratelimit())
746 dev_warn(dev, "Invalid extra type: %d\n",
747 extra->type);
748 err = -EINVAL;
749 } else {
750 memcpy(&extras[extra->type - 1], extra,
751 sizeof(*extra));
752 }
753
754 skb = xennet_get_rx_skb(queue, cons);
755 ref = xennet_get_rx_ref(queue, cons);
756 xennet_move_rx_slot(queue, skb, ref);
757 } while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE);
758
759 queue->rx.rsp_cons = cons;
760 return err;
761 }
762
763 static int xennet_get_responses(struct netfront_queue *queue,
764 struct netfront_rx_info *rinfo, RING_IDX rp,
765 struct sk_buff_head *list)
766 {
767 struct xen_netif_rx_response *rx = &rinfo->rx;
768 struct xen_netif_extra_info *extras = rinfo->extras;
769 struct device *dev = &queue->info->netdev->dev;
770 RING_IDX cons = queue->rx.rsp_cons;
771 struct sk_buff *skb = xennet_get_rx_skb(queue, cons);
772 grant_ref_t ref = xennet_get_rx_ref(queue, cons);
773 int max = MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD);
774 int slots = 1;
775 int err = 0;
776 unsigned long ret;
777
778 if (rx->flags & XEN_NETRXF_extra_info) {
779 err = xennet_get_extras(queue, extras, rp);
780 cons = queue->rx.rsp_cons;
781 }
782
783 for (;;) {
784 if (unlikely(rx->status < 0 ||
785 rx->offset + rx->status > XEN_PAGE_SIZE)) {
786 if (net_ratelimit())
787 dev_warn(dev, "rx->offset: %u, size: %d\n",
788 rx->offset, rx->status);
789 xennet_move_rx_slot(queue, skb, ref);
790 err = -EINVAL;
791 goto next;
792 }
793
794 /*
795 * This definitely indicates a bug, either in this driver or in
796 * the backend driver. In future this should flag the bad
797 * situation to the system controller to reboot the backend.
798 */
799 if (ref == GRANT_INVALID_REF) {
800 if (net_ratelimit())
801 dev_warn(dev, "Bad rx response id %d.\n",
802 rx->id);
803 err = -EINVAL;
804 goto next;
805 }
806
807 ret = gnttab_end_foreign_access_ref(ref, 0);
808 BUG_ON(!ret);
809
810 gnttab_release_grant_reference(&queue->gref_rx_head, ref);
811
812 __skb_queue_tail(list, skb);
813
814 next:
815 if (!(rx->flags & XEN_NETRXF_more_data))
816 break;
817
818 if (cons + slots == rp) {
819 if (net_ratelimit())
820 dev_warn(dev, "Need more slots\n");
821 err = -ENOENT;
822 break;
823 }
824
825 rx = RING_GET_RESPONSE(&queue->rx, cons + slots);
826 skb = xennet_get_rx_skb(queue, cons + slots);
827 ref = xennet_get_rx_ref(queue, cons + slots);
828 slots++;
829 }
830
831 if (unlikely(slots > max)) {
832 if (net_ratelimit())
833 dev_warn(dev, "Too many slots\n");
834 err = -E2BIG;
835 }
836
837 if (unlikely(err))
838 queue->rx.rsp_cons = cons + slots;
839
840 return err;
841 }
842
843 static int xennet_set_skb_gso(struct sk_buff *skb,
844 struct xen_netif_extra_info *gso)
845 {
846 if (!gso->u.gso.size) {
847 if (net_ratelimit())
848 pr_warn("GSO size must not be zero\n");
849 return -EINVAL;
850 }
851
852 if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4 &&
853 gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV6) {
854 if (net_ratelimit())
855 pr_warn("Bad GSO type %d\n", gso->u.gso.type);
856 return -EINVAL;
857 }
858
859 skb_shinfo(skb)->gso_size = gso->u.gso.size;
860 skb_shinfo(skb)->gso_type =
861 (gso->u.gso.type == XEN_NETIF_GSO_TYPE_TCPV4) ?
862 SKB_GSO_TCPV4 :
863 SKB_GSO_TCPV6;
864
865 /* Header must be checked, and gso_segs computed. */
866 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
867 skb_shinfo(skb)->gso_segs = 0;
868
869 return 0;
870 }
871
872 static RING_IDX xennet_fill_frags(struct netfront_queue *queue,
873 struct sk_buff *skb,
874 struct sk_buff_head *list)
875 {
876 struct skb_shared_info *shinfo = skb_shinfo(skb);
877 RING_IDX cons = queue->rx.rsp_cons;
878 struct sk_buff *nskb;
879
880 while ((nskb = __skb_dequeue(list))) {
881 struct xen_netif_rx_response *rx =
882 RING_GET_RESPONSE(&queue->rx, ++cons);
883 skb_frag_t *nfrag = &skb_shinfo(nskb)->frags[0];
884
885 if (shinfo->nr_frags == MAX_SKB_FRAGS) {
886 unsigned int pull_to = NETFRONT_SKB_CB(skb)->pull_to;
887
888 BUG_ON(pull_to <= skb_headlen(skb));
889 __pskb_pull_tail(skb, pull_to - skb_headlen(skb));
890 }
891 BUG_ON(shinfo->nr_frags >= MAX_SKB_FRAGS);
892
893 skb_add_rx_frag(skb, shinfo->nr_frags, skb_frag_page(nfrag),
894 rx->offset, rx->status, PAGE_SIZE);
895
896 skb_shinfo(nskb)->nr_frags = 0;
897 kfree_skb(nskb);
898 }
899
900 return cons;
901 }
902
903 static int checksum_setup(struct net_device *dev, struct sk_buff *skb)
904 {
905 bool recalculate_partial_csum = false;
906
907 /*
908 * A GSO SKB must be CHECKSUM_PARTIAL. However some buggy
909 * peers can fail to set NETRXF_csum_blank when sending a GSO
910 * frame. In this case force the SKB to CHECKSUM_PARTIAL and
911 * recalculate the partial checksum.
912 */
913 if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) {
914 struct netfront_info *np = netdev_priv(dev);
915 atomic_inc(&np->rx_gso_checksum_fixup);
916 skb->ip_summed = CHECKSUM_PARTIAL;
917 recalculate_partial_csum = true;
918 }
919
920 /* A non-CHECKSUM_PARTIAL SKB does not require setup. */
921 if (skb->ip_summed != CHECKSUM_PARTIAL)
922 return 0;
923
924 return skb_checksum_setup(skb, recalculate_partial_csum);
925 }
926
927 static int handle_incoming_queue(struct netfront_queue *queue,
928 struct sk_buff_head *rxq)
929 {
930 struct netfront_stats *rx_stats = this_cpu_ptr(queue->info->rx_stats);
931 int packets_dropped = 0;
932 struct sk_buff *skb;
933
934 while ((skb = __skb_dequeue(rxq)) != NULL) {
935 int pull_to = NETFRONT_SKB_CB(skb)->pull_to;
936
937 if (pull_to > skb_headlen(skb))
938 __pskb_pull_tail(skb, pull_to - skb_headlen(skb));
939
940 /* Ethernet work: Delayed to here as it peeks the header. */
941 skb->protocol = eth_type_trans(skb, queue->info->netdev);
942 skb_reset_network_header(skb);
943
944 if (checksum_setup(queue->info->netdev, skb)) {
945 kfree_skb(skb);
946 packets_dropped++;
947 queue->info->netdev->stats.rx_errors++;
948 continue;
949 }
950
951 u64_stats_update_begin(&rx_stats->syncp);
952 rx_stats->packets++;
953 rx_stats->bytes += skb->len;
954 u64_stats_update_end(&rx_stats->syncp);
955
956 /* Pass it up. */
957 napi_gro_receive(&queue->napi, skb);
958 }
959
960 return packets_dropped;
961 }
962
963 static int xennet_poll(struct napi_struct *napi, int budget)
964 {
965 struct netfront_queue *queue = container_of(napi, struct netfront_queue, napi);
966 struct net_device *dev = queue->info->netdev;
967 struct sk_buff *skb;
968 struct netfront_rx_info rinfo;
969 struct xen_netif_rx_response *rx = &rinfo.rx;
970 struct xen_netif_extra_info *extras = rinfo.extras;
971 RING_IDX i, rp;
972 int work_done;
973 struct sk_buff_head rxq;
974 struct sk_buff_head errq;
975 struct sk_buff_head tmpq;
976 int err;
977
978 spin_lock(&queue->rx_lock);
979
980 skb_queue_head_init(&rxq);
981 skb_queue_head_init(&errq);
982 skb_queue_head_init(&tmpq);
983
984 rp = queue->rx.sring->rsp_prod;
985 rmb(); /* Ensure we see queued responses up to 'rp'. */
986
987 i = queue->rx.rsp_cons;
988 work_done = 0;
989 while ((i != rp) && (work_done < budget)) {
990 memcpy(rx, RING_GET_RESPONSE(&queue->rx, i), sizeof(*rx));
991 memset(extras, 0, sizeof(rinfo.extras));
992
993 err = xennet_get_responses(queue, &rinfo, rp, &tmpq);
994
995 if (unlikely(err)) {
996 err:
997 while ((skb = __skb_dequeue(&tmpq)))
998 __skb_queue_tail(&errq, skb);
999 dev->stats.rx_errors++;
1000 i = queue->rx.rsp_cons;
1001 continue;
1002 }
1003
1004 skb = __skb_dequeue(&tmpq);
1005
1006 if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) {
1007 struct xen_netif_extra_info *gso;
1008 gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1];
1009
1010 if (unlikely(xennet_set_skb_gso(skb, gso))) {
1011 __skb_queue_head(&tmpq, skb);
1012 queue->rx.rsp_cons += skb_queue_len(&tmpq);
1013 goto err;
1014 }
1015 }
1016
1017 NETFRONT_SKB_CB(skb)->pull_to = rx->status;
1018 if (NETFRONT_SKB_CB(skb)->pull_to > RX_COPY_THRESHOLD)
1019 NETFRONT_SKB_CB(skb)->pull_to = RX_COPY_THRESHOLD;
1020
1021 skb_shinfo(skb)->frags[0].page_offset = rx->offset;
1022 skb_frag_size_set(&skb_shinfo(skb)->frags[0], rx->status);
1023 skb->data_len = rx->status;
1024 skb->len += rx->status;
1025
1026 i = xennet_fill_frags(queue, skb, &tmpq);
1027
1028 if (rx->flags & XEN_NETRXF_csum_blank)
1029 skb->ip_summed = CHECKSUM_PARTIAL;
1030 else if (rx->flags & XEN_NETRXF_data_validated)
1031 skb->ip_summed = CHECKSUM_UNNECESSARY;
1032
1033 __skb_queue_tail(&rxq, skb);
1034
1035 queue->rx.rsp_cons = ++i;
1036 work_done++;
1037 }
1038
1039 __skb_queue_purge(&errq);
1040
1041 work_done -= handle_incoming_queue(queue, &rxq);
1042
1043 xennet_alloc_rx_buffers(queue);
1044
1045 if (work_done < budget) {
1046 int more_to_do = 0;
1047
1048 napi_complete(napi);
1049
1050 RING_FINAL_CHECK_FOR_RESPONSES(&queue->rx, more_to_do);
1051 if (more_to_do)
1052 napi_schedule(napi);
1053 }
1054
1055 spin_unlock(&queue->rx_lock);
1056
1057 return work_done;
1058 }
1059
1060 static int xennet_change_mtu(struct net_device *dev, int mtu)
1061 {
1062 int max = xennet_can_sg(dev) ? XEN_NETIF_MAX_TX_SIZE : ETH_DATA_LEN;
1063
1064 if (mtu > max)
1065 return -EINVAL;
1066 dev->mtu = mtu;
1067 return 0;
1068 }
1069
1070 static struct rtnl_link_stats64 *xennet_get_stats64(struct net_device *dev,
1071 struct rtnl_link_stats64 *tot)
1072 {
1073 struct netfront_info *np = netdev_priv(dev);
1074 int cpu;
1075
1076 for_each_possible_cpu(cpu) {
1077 struct netfront_stats *rx_stats = per_cpu_ptr(np->rx_stats, cpu);
1078 struct netfront_stats *tx_stats = per_cpu_ptr(np->tx_stats, cpu);
1079 u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
1080 unsigned int start;
1081
1082 do {
1083 start = u64_stats_fetch_begin_irq(&tx_stats->syncp);
1084 tx_packets = tx_stats->packets;
1085 tx_bytes = tx_stats->bytes;
1086 } while (u64_stats_fetch_retry_irq(&tx_stats->syncp, start));
1087
1088 do {
1089 start = u64_stats_fetch_begin_irq(&rx_stats->syncp);
1090 rx_packets = rx_stats->packets;
1091 rx_bytes = rx_stats->bytes;
1092 } while (u64_stats_fetch_retry_irq(&rx_stats->syncp, start));
1093
1094 tot->rx_packets += rx_packets;
1095 tot->tx_packets += tx_packets;
1096 tot->rx_bytes += rx_bytes;
1097 tot->tx_bytes += tx_bytes;
1098 }
1099
1100 tot->rx_errors = dev->stats.rx_errors;
1101 tot->tx_dropped = dev->stats.tx_dropped;
1102
1103 return tot;
1104 }
1105
1106 static void xennet_release_tx_bufs(struct netfront_queue *queue)
1107 {
1108 struct sk_buff *skb;
1109 int i;
1110
1111 for (i = 0; i < NET_TX_RING_SIZE; i++) {
1112 /* Skip over entries which are actually freelist references */
1113 if (skb_entry_is_link(&queue->tx_skbs[i]))
1114 continue;
1115
1116 skb = queue->tx_skbs[i].skb;
1117 get_page(queue->grant_tx_page[i]);
1118 gnttab_end_foreign_access(queue->grant_tx_ref[i],
1119 GNTMAP_readonly,
1120 (unsigned long)page_address(queue->grant_tx_page[i]));
1121 queue->grant_tx_page[i] = NULL;
1122 queue->grant_tx_ref[i] = GRANT_INVALID_REF;
1123 add_id_to_freelist(&queue->tx_skb_freelist, queue->tx_skbs, i);
1124 dev_kfree_skb_irq(skb);
1125 }
1126 }
1127
1128 static void xennet_release_rx_bufs(struct netfront_queue *queue)
1129 {
1130 int id, ref;
1131
1132 spin_lock_bh(&queue->rx_lock);
1133
1134 for (id = 0; id < NET_RX_RING_SIZE; id++) {
1135 struct sk_buff *skb;
1136 struct page *page;
1137
1138 skb = queue->rx_skbs[id];
1139 if (!skb)
1140 continue;
1141
1142 ref = queue->grant_rx_ref[id];
1143 if (ref == GRANT_INVALID_REF)
1144 continue;
1145
1146 page = skb_frag_page(&skb_shinfo(skb)->frags[0]);
1147
1148 /* gnttab_end_foreign_access() needs a page ref until
1149 * foreign access is ended (which may be deferred).
1150 */
1151 get_page(page);
1152 gnttab_end_foreign_access(ref, 0,
1153 (unsigned long)page_address(page));
1154 queue->grant_rx_ref[id] = GRANT_INVALID_REF;
1155
1156 kfree_skb(skb);
1157 }
1158
1159 spin_unlock_bh(&queue->rx_lock);
1160 }
1161
1162 static netdev_features_t xennet_fix_features(struct net_device *dev,
1163 netdev_features_t features)
1164 {
1165 struct netfront_info *np = netdev_priv(dev);
1166 int val;
1167
1168 if (features & NETIF_F_SG) {
1169 if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, "feature-sg",
1170 "%d", &val) < 0)
1171 val = 0;
1172
1173 if (!val)
1174 features &= ~NETIF_F_SG;
1175 }
1176
1177 if (features & NETIF_F_IPV6_CSUM) {
1178 if (xenbus_scanf(XBT_NIL, np->xbdev->otherend,
1179 "feature-ipv6-csum-offload", "%d", &val) < 0)
1180 val = 0;
1181
1182 if (!val)
1183 features &= ~NETIF_F_IPV6_CSUM;
1184 }
1185
1186 if (features & NETIF_F_TSO) {
1187 if (xenbus_scanf(XBT_NIL, np->xbdev->otherend,
1188 "feature-gso-tcpv4", "%d", &val) < 0)
1189 val = 0;
1190
1191 if (!val)
1192 features &= ~NETIF_F_TSO;
1193 }
1194
1195 if (features & NETIF_F_TSO6) {
1196 if (xenbus_scanf(XBT_NIL, np->xbdev->otherend,
1197 "feature-gso-tcpv6", "%d", &val) < 0)
1198 val = 0;
1199
1200 if (!val)
1201 features &= ~NETIF_F_TSO6;
1202 }
1203
1204 return features;
1205 }
1206
1207 static int xennet_set_features(struct net_device *dev,
1208 netdev_features_t features)
1209 {
1210 if (!(features & NETIF_F_SG) && dev->mtu > ETH_DATA_LEN) {
1211 netdev_info(dev, "Reducing MTU because no SG offload");
1212 dev->mtu = ETH_DATA_LEN;
1213 }
1214
1215 return 0;
1216 }
1217
1218 static irqreturn_t xennet_tx_interrupt(int irq, void *dev_id)
1219 {
1220 struct netfront_queue *queue = dev_id;
1221 unsigned long flags;
1222
1223 spin_lock_irqsave(&queue->tx_lock, flags);
1224 xennet_tx_buf_gc(queue);
1225 spin_unlock_irqrestore(&queue->tx_lock, flags);
1226
1227 return IRQ_HANDLED;
1228 }
1229
1230 static irqreturn_t xennet_rx_interrupt(int irq, void *dev_id)
1231 {
1232 struct netfront_queue *queue = dev_id;
1233 struct net_device *dev = queue->info->netdev;
1234
1235 if (likely(netif_carrier_ok(dev) &&
1236 RING_HAS_UNCONSUMED_RESPONSES(&queue->rx)))
1237 napi_schedule(&queue->napi);
1238
1239 return IRQ_HANDLED;
1240 }
1241
1242 static irqreturn_t xennet_interrupt(int irq, void *dev_id)
1243 {
1244 xennet_tx_interrupt(irq, dev_id);
1245 xennet_rx_interrupt(irq, dev_id);
1246 return IRQ_HANDLED;
1247 }
1248
1249 #ifdef CONFIG_NET_POLL_CONTROLLER
1250 static void xennet_poll_controller(struct net_device *dev)
1251 {
1252 /* Poll each queue */
1253 struct netfront_info *info = netdev_priv(dev);
1254 unsigned int num_queues = dev->real_num_tx_queues;
1255 unsigned int i;
1256 for (i = 0; i < num_queues; ++i)
1257 xennet_interrupt(0, &info->queues[i]);
1258 }
1259 #endif
1260
1261 static const struct net_device_ops xennet_netdev_ops = {
1262 .ndo_open = xennet_open,
1263 .ndo_stop = xennet_close,
1264 .ndo_start_xmit = xennet_start_xmit,
1265 .ndo_change_mtu = xennet_change_mtu,
1266 .ndo_get_stats64 = xennet_get_stats64,
1267 .ndo_set_mac_address = eth_mac_addr,
1268 .ndo_validate_addr = eth_validate_addr,
1269 .ndo_fix_features = xennet_fix_features,
1270 .ndo_set_features = xennet_set_features,
1271 .ndo_select_queue = xennet_select_queue,
1272 #ifdef CONFIG_NET_POLL_CONTROLLER
1273 .ndo_poll_controller = xennet_poll_controller,
1274 #endif
1275 };
1276
1277 static void xennet_free_netdev(struct net_device *netdev)
1278 {
1279 struct netfront_info *np = netdev_priv(netdev);
1280
1281 free_percpu(np->rx_stats);
1282 free_percpu(np->tx_stats);
1283 free_netdev(netdev);
1284 }
1285
1286 static struct net_device *xennet_create_dev(struct xenbus_device *dev)
1287 {
1288 int err;
1289 struct net_device *netdev;
1290 struct netfront_info *np;
1291
1292 netdev = alloc_etherdev_mq(sizeof(struct netfront_info), xennet_max_queues);
1293 if (!netdev)
1294 return ERR_PTR(-ENOMEM);
1295
1296 np = netdev_priv(netdev);
1297 np->xbdev = dev;
1298
1299 np->queues = NULL;
1300
1301 err = -ENOMEM;
1302 np->rx_stats = netdev_alloc_pcpu_stats(struct netfront_stats);
1303 if (np->rx_stats == NULL)
1304 goto exit;
1305 np->tx_stats = netdev_alloc_pcpu_stats(struct netfront_stats);
1306 if (np->tx_stats == NULL)
1307 goto exit;
1308
1309 netdev->netdev_ops = &xennet_netdev_ops;
1310
1311 netdev->features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM |
1312 NETIF_F_GSO_ROBUST;
1313 netdev->hw_features = NETIF_F_SG |
1314 NETIF_F_IPV6_CSUM |
1315 NETIF_F_TSO | NETIF_F_TSO6;
1316
1317 /*
1318 * Assume that all hw features are available for now. This set
1319 * will be adjusted by the call to netdev_update_features() in
1320 * xennet_connect() which is the earliest point where we can
1321 * negotiate with the backend regarding supported features.
1322 */
1323 netdev->features |= netdev->hw_features;
1324
1325 netdev->ethtool_ops = &xennet_ethtool_ops;
1326 SET_NETDEV_DEV(netdev, &dev->dev);
1327
1328 np->netdev = netdev;
1329
1330 netif_carrier_off(netdev);
1331
1332 return netdev;
1333
1334 exit:
1335 xennet_free_netdev(netdev);
1336 return ERR_PTR(err);
1337 }
1338
1339 /**
1340 * Entry point to this code when a new device is created. Allocate the basic
1341 * structures and the ring buffers for communication with the backend, and
1342 * inform the backend of the appropriate details for those.
1343 */
1344 static int netfront_probe(struct xenbus_device *dev,
1345 const struct xenbus_device_id *id)
1346 {
1347 int err;
1348 struct net_device *netdev;
1349 struct netfront_info *info;
1350
1351 netdev = xennet_create_dev(dev);
1352 if (IS_ERR(netdev)) {
1353 err = PTR_ERR(netdev);
1354 xenbus_dev_fatal(dev, err, "creating netdev");
1355 return err;
1356 }
1357
1358 info = netdev_priv(netdev);
1359 dev_set_drvdata(&dev->dev, info);
1360 #ifdef CONFIG_SYSFS
1361 info->netdev->sysfs_groups[0] = &xennet_dev_group;
1362 #endif
1363 err = register_netdev(info->netdev);
1364 if (err) {
1365 pr_warn("%s: register_netdev err=%d\n", __func__, err);
1366 goto fail;
1367 }
1368
1369 return 0;
1370
1371 fail:
1372 xennet_free_netdev(netdev);
1373 dev_set_drvdata(&dev->dev, NULL);
1374 return err;
1375 }
1376
1377 static void xennet_end_access(int ref, void *page)
1378 {
1379 /* This frees the page as a side-effect */
1380 if (ref != GRANT_INVALID_REF)
1381 gnttab_end_foreign_access(ref, 0, (unsigned long)page);
1382 }
1383
1384 static void xennet_disconnect_backend(struct netfront_info *info)
1385 {
1386 unsigned int i = 0;
1387 unsigned int num_queues = info->netdev->real_num_tx_queues;
1388
1389 netif_carrier_off(info->netdev);
1390
1391 for (i = 0; i < num_queues && info->queues; ++i) {
1392 struct netfront_queue *queue = &info->queues[i];
1393
1394 if (queue->tx_irq && (queue->tx_irq == queue->rx_irq))
1395 unbind_from_irqhandler(queue->tx_irq, queue);
1396 if (queue->tx_irq && (queue->tx_irq != queue->rx_irq)) {
1397 unbind_from_irqhandler(queue->tx_irq, queue);
1398 unbind_from_irqhandler(queue->rx_irq, queue);
1399 }
1400 queue->tx_evtchn = queue->rx_evtchn = 0;
1401 queue->tx_irq = queue->rx_irq = 0;
1402
1403 if (netif_running(info->netdev))
1404 napi_synchronize(&queue->napi);
1405
1406 xennet_release_tx_bufs(queue);
1407 xennet_release_rx_bufs(queue);
1408 gnttab_free_grant_references(queue->gref_tx_head);
1409 gnttab_free_grant_references(queue->gref_rx_head);
1410
1411 /* End access and free the pages */
1412 xennet_end_access(queue->tx_ring_ref, queue->tx.sring);
1413 xennet_end_access(queue->rx_ring_ref, queue->rx.sring);
1414
1415 queue->tx_ring_ref = GRANT_INVALID_REF;
1416 queue->rx_ring_ref = GRANT_INVALID_REF;
1417 queue->tx.sring = NULL;
1418 queue->rx.sring = NULL;
1419 }
1420 }
1421
1422 /**
1423 * We are reconnecting to the backend, due to a suspend/resume, or a backend
1424 * driver restart. We tear down our netif structure and recreate it, but
1425 * leave the device-layer structures intact so that this is transparent to the
1426 * rest of the kernel.
1427 */
1428 static int netfront_resume(struct xenbus_device *dev)
1429 {
1430 struct netfront_info *info = dev_get_drvdata(&dev->dev);
1431
1432 dev_dbg(&dev->dev, "%s\n", dev->nodename);
1433
1434 xennet_disconnect_backend(info);
1435 return 0;
1436 }
1437
1438 static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[])
1439 {
1440 char *s, *e, *macstr;
1441 int i;
1442
1443 macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
1444 if (IS_ERR(macstr))
1445 return PTR_ERR(macstr);
1446
1447 for (i = 0; i < ETH_ALEN; i++) {
1448 mac[i] = simple_strtoul(s, &e, 16);
1449 if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) {
1450 kfree(macstr);
1451 return -ENOENT;
1452 }
1453 s = e+1;
1454 }
1455
1456 kfree(macstr);
1457 return 0;
1458 }
1459
1460 static int setup_netfront_single(struct netfront_queue *queue)
1461 {
1462 int err;
1463
1464 err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->tx_evtchn);
1465 if (err < 0)
1466 goto fail;
1467
1468 err = bind_evtchn_to_irqhandler(queue->tx_evtchn,
1469 xennet_interrupt,
1470 0, queue->info->netdev->name, queue);
1471 if (err < 0)
1472 goto bind_fail;
1473 queue->rx_evtchn = queue->tx_evtchn;
1474 queue->rx_irq = queue->tx_irq = err;
1475
1476 return 0;
1477
1478 bind_fail:
1479 xenbus_free_evtchn(queue->info->xbdev, queue->tx_evtchn);
1480 queue->tx_evtchn = 0;
1481 fail:
1482 return err;
1483 }
1484
1485 static int setup_netfront_split(struct netfront_queue *queue)
1486 {
1487 int err;
1488
1489 err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->tx_evtchn);
1490 if (err < 0)
1491 goto fail;
1492 err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->rx_evtchn);
1493 if (err < 0)
1494 goto alloc_rx_evtchn_fail;
1495
1496 snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name),
1497 "%s-tx", queue->name);
1498 err = bind_evtchn_to_irqhandler(queue->tx_evtchn,
1499 xennet_tx_interrupt,
1500 0, queue->tx_irq_name, queue);
1501 if (err < 0)
1502 goto bind_tx_fail;
1503 queue->tx_irq = err;
1504
1505 snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name),
1506 "%s-rx", queue->name);
1507 err = bind_evtchn_to_irqhandler(queue->rx_evtchn,
1508 xennet_rx_interrupt,
1509 0, queue->rx_irq_name, queue);
1510 if (err < 0)
1511 goto bind_rx_fail;
1512 queue->rx_irq = err;
1513
1514 return 0;
1515
1516 bind_rx_fail:
1517 unbind_from_irqhandler(queue->tx_irq, queue);
1518 queue->tx_irq = 0;
1519 bind_tx_fail:
1520 xenbus_free_evtchn(queue->info->xbdev, queue->rx_evtchn);
1521 queue->rx_evtchn = 0;
1522 alloc_rx_evtchn_fail:
1523 xenbus_free_evtchn(queue->info->xbdev, queue->tx_evtchn);
1524 queue->tx_evtchn = 0;
1525 fail:
1526 return err;
1527 }
1528
1529 static int setup_netfront(struct xenbus_device *dev,
1530 struct netfront_queue *queue, unsigned int feature_split_evtchn)
1531 {
1532 struct xen_netif_tx_sring *txs;
1533 struct xen_netif_rx_sring *rxs;
1534 grant_ref_t gref;
1535 int err;
1536
1537 queue->tx_ring_ref = GRANT_INVALID_REF;
1538 queue->rx_ring_ref = GRANT_INVALID_REF;
1539 queue->rx.sring = NULL;
1540 queue->tx.sring = NULL;
1541
1542 txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
1543 if (!txs) {
1544 err = -ENOMEM;
1545 xenbus_dev_fatal(dev, err, "allocating tx ring page");
1546 goto fail;
1547 }
1548 SHARED_RING_INIT(txs);
1549 FRONT_RING_INIT(&queue->tx, txs, XEN_PAGE_SIZE);
1550
1551 err = xenbus_grant_ring(dev, txs, 1, &gref);
1552 if (err < 0)
1553 goto grant_tx_ring_fail;
1554 queue->tx_ring_ref = gref;
1555
1556 rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
1557 if (!rxs) {
1558 err = -ENOMEM;
1559 xenbus_dev_fatal(dev, err, "allocating rx ring page");
1560 goto alloc_rx_ring_fail;
1561 }
1562 SHARED_RING_INIT(rxs);
1563 FRONT_RING_INIT(&queue->rx, rxs, XEN_PAGE_SIZE);
1564
1565 err = xenbus_grant_ring(dev, rxs, 1, &gref);
1566 if (err < 0)
1567 goto grant_rx_ring_fail;
1568 queue->rx_ring_ref = gref;
1569
1570 if (feature_split_evtchn)
1571 err = setup_netfront_split(queue);
1572 /* setup single event channel if
1573 * a) feature-split-event-channels == 0
1574 * b) feature-split-event-channels == 1 but failed to setup
1575 */
1576 if (!feature_split_evtchn || (feature_split_evtchn && err))
1577 err = setup_netfront_single(queue);
1578
1579 if (err)
1580 goto alloc_evtchn_fail;
1581
1582 return 0;
1583
1584 /* If we fail to setup netfront, it is safe to just revoke access to
1585 * granted pages because backend is not accessing it at this point.
1586 */
1587 alloc_evtchn_fail:
1588 gnttab_end_foreign_access_ref(queue->rx_ring_ref, 0);
1589 grant_rx_ring_fail:
1590 free_page((unsigned long)rxs);
1591 alloc_rx_ring_fail:
1592 gnttab_end_foreign_access_ref(queue->tx_ring_ref, 0);
1593 grant_tx_ring_fail:
1594 free_page((unsigned long)txs);
1595 fail:
1596 return err;
1597 }
1598
1599 /* Queue-specific initialisation
1600 * This used to be done in xennet_create_dev() but must now
1601 * be run per-queue.
1602 */
1603 static int xennet_init_queue(struct netfront_queue *queue)
1604 {
1605 unsigned short i;
1606 int err = 0;
1607
1608 spin_lock_init(&queue->tx_lock);
1609 spin_lock_init(&queue->rx_lock);
1610
1611 setup_timer(&queue->rx_refill_timer, rx_refill_timeout,
1612 (unsigned long)queue);
1613
1614 snprintf(queue->name, sizeof(queue->name), "%s-q%u",
1615 queue->info->netdev->name, queue->id);
1616
1617 /* Initialise tx_skbs as a free chain containing every entry. */
1618 queue->tx_skb_freelist = 0;
1619 for (i = 0; i < NET_TX_RING_SIZE; i++) {
1620 skb_entry_set_link(&queue->tx_skbs[i], i+1);
1621 queue->grant_tx_ref[i] = GRANT_INVALID_REF;
1622 queue->grant_tx_page[i] = NULL;
1623 }
1624
1625 /* Clear out rx_skbs */
1626 for (i = 0; i < NET_RX_RING_SIZE; i++) {
1627 queue->rx_skbs[i] = NULL;
1628 queue->grant_rx_ref[i] = GRANT_INVALID_REF;
1629 }
1630
1631 /* A grant for every tx ring slot */
1632 if (gnttab_alloc_grant_references(NET_TX_RING_SIZE,
1633 &queue->gref_tx_head) < 0) {
1634 pr_alert("can't alloc tx grant refs\n");
1635 err = -ENOMEM;
1636 goto exit;
1637 }
1638
1639 /* A grant for every rx ring slot */
1640 if (gnttab_alloc_grant_references(NET_RX_RING_SIZE,
1641 &queue->gref_rx_head) < 0) {
1642 pr_alert("can't alloc rx grant refs\n");
1643 err = -ENOMEM;
1644 goto exit_free_tx;
1645 }
1646
1647 return 0;
1648
1649 exit_free_tx:
1650 gnttab_free_grant_references(queue->gref_tx_head);
1651 exit:
1652 return err;
1653 }
1654
1655 static int write_queue_xenstore_keys(struct netfront_queue *queue,
1656 struct xenbus_transaction *xbt, int write_hierarchical)
1657 {
1658 /* Write the queue-specific keys into XenStore in the traditional
1659 * way for a single queue, or in a queue subkeys for multiple
1660 * queues.
1661 */
1662 struct xenbus_device *dev = queue->info->xbdev;
1663 int err;
1664 const char *message;
1665 char *path;
1666 size_t pathsize;
1667
1668 /* Choose the correct place to write the keys */
1669 if (write_hierarchical) {
1670 pathsize = strlen(dev->nodename) + 10;
1671 path = kzalloc(pathsize, GFP_KERNEL);
1672 if (!path) {
1673 err = -ENOMEM;
1674 message = "out of memory while writing ring references";
1675 goto error;
1676 }
1677 snprintf(path, pathsize, "%s/queue-%u",
1678 dev->nodename, queue->id);
1679 } else {
1680 path = (char *)dev->nodename;
1681 }
1682
1683 /* Write ring references */
1684 err = xenbus_printf(*xbt, path, "tx-ring-ref", "%u",
1685 queue->tx_ring_ref);
1686 if (err) {
1687 message = "writing tx-ring-ref";
1688 goto error;
1689 }
1690
1691 err = xenbus_printf(*xbt, path, "rx-ring-ref", "%u",
1692 queue->rx_ring_ref);
1693 if (err) {
1694 message = "writing rx-ring-ref";
1695 goto error;
1696 }
1697
1698 /* Write event channels; taking into account both shared
1699 * and split event channel scenarios.
1700 */
1701 if (queue->tx_evtchn == queue->rx_evtchn) {
1702 /* Shared event channel */
1703 err = xenbus_printf(*xbt, path,
1704 "event-channel", "%u", queue->tx_evtchn);
1705 if (err) {
1706 message = "writing event-channel";
1707 goto error;
1708 }
1709 } else {
1710 /* Split event channels */
1711 err = xenbus_printf(*xbt, path,
1712 "event-channel-tx", "%u", queue->tx_evtchn);
1713 if (err) {
1714 message = "writing event-channel-tx";
1715 goto error;
1716 }
1717
1718 err = xenbus_printf(*xbt, path,
1719 "event-channel-rx", "%u", queue->rx_evtchn);
1720 if (err) {
1721 message = "writing event-channel-rx";
1722 goto error;
1723 }
1724 }
1725
1726 if (write_hierarchical)
1727 kfree(path);
1728 return 0;
1729
1730 error:
1731 if (write_hierarchical)
1732 kfree(path);
1733 xenbus_dev_fatal(dev, err, "%s", message);
1734 return err;
1735 }
1736
1737 static void xennet_destroy_queues(struct netfront_info *info)
1738 {
1739 unsigned int i;
1740
1741 rtnl_lock();
1742
1743 for (i = 0; i < info->netdev->real_num_tx_queues; i++) {
1744 struct netfront_queue *queue = &info->queues[i];
1745
1746 if (netif_running(info->netdev))
1747 napi_disable(&queue->napi);
1748 del_timer_sync(&queue->rx_refill_timer);
1749 netif_napi_del(&queue->napi);
1750 }
1751
1752 rtnl_unlock();
1753
1754 kfree(info->queues);
1755 info->queues = NULL;
1756 }
1757
1758 static int xennet_create_queues(struct netfront_info *info,
1759 unsigned int *num_queues)
1760 {
1761 unsigned int i;
1762 int ret;
1763
1764 info->queues = kcalloc(*num_queues, sizeof(struct netfront_queue),
1765 GFP_KERNEL);
1766 if (!info->queues)
1767 return -ENOMEM;
1768
1769 rtnl_lock();
1770
1771 for (i = 0; i < *num_queues; i++) {
1772 struct netfront_queue *queue = &info->queues[i];
1773
1774 queue->id = i;
1775 queue->info = info;
1776
1777 ret = xennet_init_queue(queue);
1778 if (ret < 0) {
1779 dev_warn(&info->netdev->dev,
1780 "only created %d queues\n", i);
1781 *num_queues = i;
1782 break;
1783 }
1784
1785 netif_napi_add(queue->info->netdev, &queue->napi,
1786 xennet_poll, 64);
1787 if (netif_running(info->netdev))
1788 napi_enable(&queue->napi);
1789 }
1790
1791 netif_set_real_num_tx_queues(info->netdev, *num_queues);
1792
1793 rtnl_unlock();
1794
1795 if (*num_queues == 0) {
1796 dev_err(&info->netdev->dev, "no queues\n");
1797 return -EINVAL;
1798 }
1799 return 0;
1800 }
1801
1802 /* Common code used when first setting up, and when resuming. */
1803 static int talk_to_netback(struct xenbus_device *dev,
1804 struct netfront_info *info)
1805 {
1806 const char *message;
1807 struct xenbus_transaction xbt;
1808 int err;
1809 unsigned int feature_split_evtchn;
1810 unsigned int i = 0;
1811 unsigned int max_queues = 0;
1812 struct netfront_queue *queue = NULL;
1813 unsigned int num_queues = 1;
1814
1815 info->netdev->irq = 0;
1816
1817 /* Check if backend supports multiple queues */
1818 err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
1819 "multi-queue-max-queues", "%u", &max_queues);
1820 if (err < 0)
1821 max_queues = 1;
1822 num_queues = min(max_queues, xennet_max_queues);
1823
1824 /* Check feature-split-event-channels */
1825 err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
1826 "feature-split-event-channels", "%u",
1827 &feature_split_evtchn);
1828 if (err < 0)
1829 feature_split_evtchn = 0;
1830
1831 /* Read mac addr. */
1832 err = xen_net_read_mac(dev, info->netdev->dev_addr);
1833 if (err) {
1834 xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
1835 goto out;
1836 }
1837
1838 if (info->queues)
1839 xennet_destroy_queues(info);
1840
1841 err = xennet_create_queues(info, &num_queues);
1842 if (err < 0)
1843 goto destroy_ring;
1844
1845 /* Create shared ring, alloc event channel -- for each queue */
1846 for (i = 0; i < num_queues; ++i) {
1847 queue = &info->queues[i];
1848 err = setup_netfront(dev, queue, feature_split_evtchn);
1849 if (err) {
1850 /* setup_netfront() will tidy up the current
1851 * queue on error, but we need to clean up
1852 * those already allocated.
1853 */
1854 if (i > 0) {
1855 rtnl_lock();
1856 netif_set_real_num_tx_queues(info->netdev, i);
1857 rtnl_unlock();
1858 goto destroy_ring;
1859 } else {
1860 goto out;
1861 }
1862 }
1863 }
1864
1865 again:
1866 err = xenbus_transaction_start(&xbt);
1867 if (err) {
1868 xenbus_dev_fatal(dev, err, "starting transaction");
1869 goto destroy_ring;
1870 }
1871
1872 if (xenbus_exists(XBT_NIL,
1873 info->xbdev->otherend, "multi-queue-max-queues")) {
1874 /* Write the number of queues */
1875 err = xenbus_printf(xbt, dev->nodename,
1876 "multi-queue-num-queues", "%u", num_queues);
1877 if (err) {
1878 message = "writing multi-queue-num-queues";
1879 goto abort_transaction_no_dev_fatal;
1880 }
1881 }
1882
1883 if (num_queues == 1) {
1884 err = write_queue_xenstore_keys(&info->queues[0], &xbt, 0); /* flat */
1885 if (err)
1886 goto abort_transaction_no_dev_fatal;
1887 } else {
1888 /* Write the keys for each queue */
1889 for (i = 0; i < num_queues; ++i) {
1890 queue = &info->queues[i];
1891 err = write_queue_xenstore_keys(queue, &xbt, 1); /* hierarchical */
1892 if (err)
1893 goto abort_transaction_no_dev_fatal;
1894 }
1895 }
1896
1897 /* The remaining keys are not queue-specific */
1898 err = xenbus_printf(xbt, dev->nodename, "request-rx-copy", "%u",
1899 1);
1900 if (err) {
1901 message = "writing request-rx-copy";
1902 goto abort_transaction;
1903 }
1904
1905 err = xenbus_printf(xbt, dev->nodename, "feature-rx-notify", "%d", 1);
1906 if (err) {
1907 message = "writing feature-rx-notify";
1908 goto abort_transaction;
1909 }
1910
1911 err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", 1);
1912 if (err) {
1913 message = "writing feature-sg";
1914 goto abort_transaction;
1915 }
1916
1917 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4", "%d", 1);
1918 if (err) {
1919 message = "writing feature-gso-tcpv4";
1920 goto abort_transaction;
1921 }
1922
1923 err = xenbus_write(xbt, dev->nodename, "feature-gso-tcpv6", "1");
1924 if (err) {
1925 message = "writing feature-gso-tcpv6";
1926 goto abort_transaction;
1927 }
1928
1929 err = xenbus_write(xbt, dev->nodename, "feature-ipv6-csum-offload",
1930 "1");
1931 if (err) {
1932 message = "writing feature-ipv6-csum-offload";
1933 goto abort_transaction;
1934 }
1935
1936 err = xenbus_transaction_end(xbt, 0);
1937 if (err) {
1938 if (err == -EAGAIN)
1939 goto again;
1940 xenbus_dev_fatal(dev, err, "completing transaction");
1941 goto destroy_ring;
1942 }
1943
1944 return 0;
1945
1946 abort_transaction:
1947 xenbus_dev_fatal(dev, err, "%s", message);
1948 abort_transaction_no_dev_fatal:
1949 xenbus_transaction_end(xbt, 1);
1950 destroy_ring:
1951 xennet_disconnect_backend(info);
1952 kfree(info->queues);
1953 info->queues = NULL;
1954 out:
1955 return err;
1956 }
1957
1958 static int xennet_connect(struct net_device *dev)
1959 {
1960 struct netfront_info *np = netdev_priv(dev);
1961 unsigned int num_queues = 0;
1962 int err;
1963 unsigned int feature_rx_copy;
1964 unsigned int j = 0;
1965 struct netfront_queue *queue = NULL;
1966
1967 err = xenbus_scanf(XBT_NIL, np->xbdev->otherend,
1968 "feature-rx-copy", "%u", &feature_rx_copy);
1969 if (err != 1)
1970 feature_rx_copy = 0;
1971
1972 if (!feature_rx_copy) {
1973 dev_info(&dev->dev,
1974 "backend does not support copying receive path\n");
1975 return -ENODEV;
1976 }
1977
1978 err = talk_to_netback(np->xbdev, np);
1979 if (err)
1980 return err;
1981
1982 /* talk_to_netback() sets the correct number of queues */
1983 num_queues = dev->real_num_tx_queues;
1984
1985 rtnl_lock();
1986 netdev_update_features(dev);
1987 rtnl_unlock();
1988
1989 /*
1990 * All public and private state should now be sane. Get
1991 * ready to start sending and receiving packets and give the driver
1992 * domain a kick because we've probably just requeued some
1993 * packets.
1994 */
1995 netif_carrier_on(np->netdev);
1996 for (j = 0; j < num_queues; ++j) {
1997 queue = &np->queues[j];
1998
1999 notify_remote_via_irq(queue->tx_irq);
2000 if (queue->tx_irq != queue->rx_irq)
2001 notify_remote_via_irq(queue->rx_irq);
2002
2003 spin_lock_irq(&queue->tx_lock);
2004 xennet_tx_buf_gc(queue);
2005 spin_unlock_irq(&queue->tx_lock);
2006
2007 spin_lock_bh(&queue->rx_lock);
2008 xennet_alloc_rx_buffers(queue);
2009 spin_unlock_bh(&queue->rx_lock);
2010 }
2011
2012 return 0;
2013 }
2014
2015 /**
2016 * Callback received when the backend's state changes.
2017 */
2018 static void netback_changed(struct xenbus_device *dev,
2019 enum xenbus_state backend_state)
2020 {
2021 struct netfront_info *np = dev_get_drvdata(&dev->dev);
2022 struct net_device *netdev = np->netdev;
2023
2024 dev_dbg(&dev->dev, "%s\n", xenbus_strstate(backend_state));
2025
2026 switch (backend_state) {
2027 case XenbusStateInitialising:
2028 case XenbusStateInitialised:
2029 case XenbusStateReconfiguring:
2030 case XenbusStateReconfigured:
2031 case XenbusStateUnknown:
2032 break;
2033
2034 case XenbusStateInitWait:
2035 if (dev->state != XenbusStateInitialising)
2036 break;
2037 if (xennet_connect(netdev) != 0)
2038 break;
2039 xenbus_switch_state(dev, XenbusStateConnected);
2040 break;
2041
2042 case XenbusStateConnected:
2043 netdev_notify_peers(netdev);
2044 break;
2045
2046 case XenbusStateClosed:
2047 if (dev->state == XenbusStateClosed)
2048 break;
2049 /* Missed the backend's CLOSING state -- fallthrough */
2050 case XenbusStateClosing:
2051 xenbus_frontend_closed(dev);
2052 break;
2053 }
2054 }
2055
2056 static const struct xennet_stat {
2057 char name[ETH_GSTRING_LEN];
2058 u16 offset;
2059 } xennet_stats[] = {
2060 {
2061 "rx_gso_checksum_fixup",
2062 offsetof(struct netfront_info, rx_gso_checksum_fixup)
2063 },
2064 };
2065
2066 static int xennet_get_sset_count(struct net_device *dev, int string_set)
2067 {
2068 switch (string_set) {
2069 case ETH_SS_STATS:
2070 return ARRAY_SIZE(xennet_stats);
2071 default:
2072 return -EINVAL;
2073 }
2074 }
2075
2076 static void xennet_get_ethtool_stats(struct net_device *dev,
2077 struct ethtool_stats *stats, u64 * data)
2078 {
2079 void *np = netdev_priv(dev);
2080 int i;
2081
2082 for (i = 0; i < ARRAY_SIZE(xennet_stats); i++)
2083 data[i] = atomic_read((atomic_t *)(np + xennet_stats[i].offset));
2084 }
2085
2086 static void xennet_get_strings(struct net_device *dev, u32 stringset, u8 * data)
2087 {
2088 int i;
2089
2090 switch (stringset) {
2091 case ETH_SS_STATS:
2092 for (i = 0; i < ARRAY_SIZE(xennet_stats); i++)
2093 memcpy(data + i * ETH_GSTRING_LEN,
2094 xennet_stats[i].name, ETH_GSTRING_LEN);
2095 break;
2096 }
2097 }
2098
2099 static const struct ethtool_ops xennet_ethtool_ops =
2100 {
2101 .get_link = ethtool_op_get_link,
2102
2103 .get_sset_count = xennet_get_sset_count,
2104 .get_ethtool_stats = xennet_get_ethtool_stats,
2105 .get_strings = xennet_get_strings,
2106 };
2107
2108 #ifdef CONFIG_SYSFS
2109 static ssize_t show_rxbuf(struct device *dev,
2110 struct device_attribute *attr, char *buf)
2111 {
2112 return sprintf(buf, "%lu\n", NET_RX_RING_SIZE);
2113 }
2114
2115 static ssize_t store_rxbuf(struct device *dev,
2116 struct device_attribute *attr,
2117 const char *buf, size_t len)
2118 {
2119 char *endp;
2120 unsigned long target;
2121
2122 if (!capable(CAP_NET_ADMIN))
2123 return -EPERM;
2124
2125 target = simple_strtoul(buf, &endp, 0);
2126 if (endp == buf)
2127 return -EBADMSG;
2128
2129 /* rxbuf_min and rxbuf_max are no longer configurable. */
2130
2131 return len;
2132 }
2133
2134 static DEVICE_ATTR(rxbuf_min, S_IRUGO|S_IWUSR, show_rxbuf, store_rxbuf);
2135 static DEVICE_ATTR(rxbuf_max, S_IRUGO|S_IWUSR, show_rxbuf, store_rxbuf);
2136 static DEVICE_ATTR(rxbuf_cur, S_IRUGO, show_rxbuf, NULL);
2137
2138 static struct attribute *xennet_dev_attrs[] = {
2139 &dev_attr_rxbuf_min.attr,
2140 &dev_attr_rxbuf_max.attr,
2141 &dev_attr_rxbuf_cur.attr,
2142 NULL
2143 };
2144
2145 static const struct attribute_group xennet_dev_group = {
2146 .attrs = xennet_dev_attrs
2147 };
2148 #endif /* CONFIG_SYSFS */
2149
2150 static int xennet_remove(struct xenbus_device *dev)
2151 {
2152 struct netfront_info *info = dev_get_drvdata(&dev->dev);
2153
2154 dev_dbg(&dev->dev, "%s\n", dev->nodename);
2155
2156 xennet_disconnect_backend(info);
2157
2158 unregister_netdev(info->netdev);
2159
2160 if (info->queues)
2161 xennet_destroy_queues(info);
2162 xennet_free_netdev(info->netdev);
2163
2164 return 0;
2165 }
2166
2167 static const struct xenbus_device_id netfront_ids[] = {
2168 { "vif" },
2169 { "" }
2170 };
2171
2172 static struct xenbus_driver netfront_driver = {
2173 .ids = netfront_ids,
2174 .probe = netfront_probe,
2175 .remove = xennet_remove,
2176 .resume = netfront_resume,
2177 .otherend_changed = netback_changed,
2178 };
2179
2180 static int __init netif_init(void)
2181 {
2182 if (!xen_domain())
2183 return -ENODEV;
2184
2185 if (!xen_has_pv_nic_devices())
2186 return -ENODEV;
2187
2188 pr_info("Initialising Xen virtual ethernet driver\n");
2189
2190 /* Allow as many queues as there are CPUs if user has not
2191 * specified a value.
2192 */
2193 if (xennet_max_queues == 0)
2194 xennet_max_queues = num_online_cpus();
2195
2196 return xenbus_register_frontend(&netfront_driver);
2197 }
2198 module_init(netif_init);
2199
2200
2201 static void __exit netif_exit(void)
2202 {
2203 xenbus_unregister_driver(&netfront_driver);
2204 }
2205 module_exit(netif_exit);
2206
2207 MODULE_DESCRIPTION("Xen virtual network device frontend");
2208 MODULE_LICENSE("GPL");
2209 MODULE_ALIAS("xen:vif");
2210 MODULE_ALIAS("xennet");
Linux with added FPC-III support