2 * Virtual network driver for conversing with remote driver backends.
4 * Copyright (c) 2002-2005, K A Fraser
5 * Copyright (c) 2005, XenSource Ltd
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:
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:
20 * The above copyright notice and this permission notice shall be included in
21 * all copies or substantial portions of the Software.
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
32 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
42 #include <linux/udp.h>
43 #include <linux/moduleparam.h>
45 #include <linux/slab.h>
48 #include <asm/xen/page.h>
50 #include <xen/xenbus.h>
51 #include <xen/events.h>
53 #include <xen/platform_pci.h>
54 #include <xen/grant_table.h>
56 #include <xen/interface/io/netif.h>
57 #include <xen/interface/memory.h>
58 #include <xen/interface/grant_table.h>
60 /* Module parameters */
61 static unsigned int xennet_max_queues
;
62 module_param_named(max_queues
, xennet_max_queues
, uint
, 0644);
63 MODULE_PARM_DESC(max_queues
,
64 "Maximum number of queues per virtual interface");
66 static const struct ethtool_ops xennet_ethtool_ops
;
72 #define NETFRONT_SKB_CB(skb) ((struct netfront_cb *)((skb)->cb))
74 #define RX_COPY_THRESHOLD 256
76 #define GRANT_INVALID_REF 0
78 #define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE)
79 #define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE)
80 #define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256)
82 /* Queue name is interface name with "-qNNN" appended */
83 #define QUEUE_NAME_SIZE (IFNAMSIZ + 6)
85 /* IRQ name is queue name with "-tx" or "-rx" appended */
86 #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3)
88 struct netfront_stats
{
93 struct u64_stats_sync syncp
;
98 struct netfront_queue
{
99 unsigned int id
; /* Queue ID, 0-based */
100 char name
[QUEUE_NAME_SIZE
]; /* DEVNAME-qN */
101 struct netfront_info
*info
;
103 struct napi_struct napi
;
105 /* Split event channels support, tx_* == rx_* when using
106 * single event channel.
108 unsigned int tx_evtchn
, rx_evtchn
;
109 unsigned int tx_irq
, rx_irq
;
110 /* Only used when split event channels support is enabled */
111 char tx_irq_name
[IRQ_NAME_SIZE
]; /* DEVNAME-qN-tx */
112 char rx_irq_name
[IRQ_NAME_SIZE
]; /* DEVNAME-qN-rx */
115 struct xen_netif_tx_front_ring tx
;
119 * {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries
120 * are linked from tx_skb_freelist through skb_entry.link.
122 * NB. Freelist index entries are always going to be less than
123 * PAGE_OFFSET, whereas pointers to skbs will always be equal or
124 * greater than PAGE_OFFSET: we use this property to distinguish
130 } tx_skbs
[NET_TX_RING_SIZE
];
131 grant_ref_t gref_tx_head
;
132 grant_ref_t grant_tx_ref
[NET_TX_RING_SIZE
];
133 struct page
*grant_tx_page
[NET_TX_RING_SIZE
];
134 unsigned tx_skb_freelist
;
136 spinlock_t rx_lock ____cacheline_aligned_in_smp
;
137 struct xen_netif_rx_front_ring rx
;
140 /* Receive-ring batched refills. */
141 #define RX_MIN_TARGET 8
142 #define RX_DFL_MIN_TARGET 64
143 #define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256)
144 unsigned rx_min_target
, rx_max_target
, rx_target
;
145 struct sk_buff_head rx_batch
;
147 struct timer_list rx_refill_timer
;
149 struct sk_buff
*rx_skbs
[NET_RX_RING_SIZE
];
150 grant_ref_t gref_rx_head
;
151 grant_ref_t grant_rx_ref
[NET_RX_RING_SIZE
];
153 unsigned long rx_pfn_array
[NET_RX_RING_SIZE
];
154 struct multicall_entry rx_mcl
[NET_RX_RING_SIZE
+1];
155 struct mmu_update rx_mmu
[NET_RX_RING_SIZE
];
158 struct netfront_info
{
159 struct list_head list
;
160 struct net_device
*netdev
;
162 struct xenbus_device
*xbdev
;
164 /* Multi-queue support */
165 struct netfront_queue
*queues
;
168 struct netfront_stats __percpu
*stats
;
170 atomic_t rx_gso_checksum_fixup
;
173 struct netfront_rx_info
{
174 struct xen_netif_rx_response rx
;
175 struct xen_netif_extra_info extras
[XEN_NETIF_EXTRA_TYPE_MAX
- 1];
178 static void skb_entry_set_link(union skb_entry
*list
, unsigned short id
)
183 static int skb_entry_is_link(const union skb_entry
*list
)
185 BUILD_BUG_ON(sizeof(list
->skb
) != sizeof(list
->link
));
186 return (unsigned long)list
->skb
< PAGE_OFFSET
;
190 * Access macros for acquiring freeing slots in tx_skbs[].
193 static void add_id_to_freelist(unsigned *head
, union skb_entry
*list
,
196 skb_entry_set_link(&list
[id
], *head
);
200 static unsigned short get_id_from_freelist(unsigned *head
,
201 union skb_entry
*list
)
203 unsigned int id
= *head
;
204 *head
= list
[id
].link
;
208 static int xennet_rxidx(RING_IDX idx
)
210 return idx
& (NET_RX_RING_SIZE
- 1);
213 static struct sk_buff
*xennet_get_rx_skb(struct netfront_queue
*queue
,
216 int i
= xennet_rxidx(ri
);
217 struct sk_buff
*skb
= queue
->rx_skbs
[i
];
218 queue
->rx_skbs
[i
] = NULL
;
222 static grant_ref_t
xennet_get_rx_ref(struct netfront_queue
*queue
,
225 int i
= xennet_rxidx(ri
);
226 grant_ref_t ref
= queue
->grant_rx_ref
[i
];
227 queue
->grant_rx_ref
[i
] = GRANT_INVALID_REF
;
232 static int xennet_sysfs_addif(struct net_device
*netdev
);
233 static void xennet_sysfs_delif(struct net_device
*netdev
);
234 #else /* !CONFIG_SYSFS */
235 #define xennet_sysfs_addif(dev) (0)
236 #define xennet_sysfs_delif(dev) do { } while (0)
239 static bool xennet_can_sg(struct net_device
*dev
)
241 return dev
->features
& NETIF_F_SG
;
245 static void rx_refill_timeout(unsigned long data
)
247 struct netfront_queue
*queue
= (struct netfront_queue
*)data
;
248 napi_schedule(&queue
->napi
);
251 static int netfront_tx_slot_available(struct netfront_queue
*queue
)
253 return (queue
->tx
.req_prod_pvt
- queue
->tx
.rsp_cons
) <
254 (TX_MAX_TARGET
- MAX_SKB_FRAGS
- 2);
257 static void xennet_maybe_wake_tx(struct netfront_queue
*queue
)
259 struct net_device
*dev
= queue
->info
->netdev
;
260 struct netdev_queue
*dev_queue
= netdev_get_tx_queue(dev
, queue
->id
);
262 if (unlikely(netif_tx_queue_stopped(dev_queue
)) &&
263 netfront_tx_slot_available(queue
) &&
264 likely(netif_running(dev
)))
265 netif_tx_wake_queue(netdev_get_tx_queue(dev
, queue
->id
));
268 static void xennet_alloc_rx_buffers(struct netfront_queue
*queue
)
273 int i
, batch_target
, notify
;
274 RING_IDX req_prod
= queue
->rx
.req_prod_pvt
;
278 struct xen_netif_rx_request
*req
;
280 if (unlikely(!netif_carrier_ok(queue
->info
->netdev
)))
284 * Allocate skbuffs greedily, even though we batch updates to the
285 * receive ring. This creates a less bursty demand on the memory
286 * allocator, so should reduce the chance of failed allocation requests
287 * both for ourself and for other kernel subsystems.
289 batch_target
= queue
->rx_target
- (req_prod
- queue
->rx
.rsp_cons
);
290 for (i
= skb_queue_len(&queue
->rx_batch
); i
< batch_target
; i
++) {
291 skb
= __netdev_alloc_skb(queue
->info
->netdev
,
292 RX_COPY_THRESHOLD
+ NET_IP_ALIGN
,
293 GFP_ATOMIC
| __GFP_NOWARN
);
297 /* Align ip header to a 16 bytes boundary */
298 skb_reserve(skb
, NET_IP_ALIGN
);
300 page
= alloc_page(GFP_ATOMIC
| __GFP_NOWARN
);
304 /* Could not allocate any skbuffs. Try again later. */
305 mod_timer(&queue
->rx_refill_timer
,
308 /* Any skbuffs queued for refill? Force them out. */
314 skb_add_rx_frag(skb
, 0, page
, 0, 0, PAGE_SIZE
);
315 __skb_queue_tail(&queue
->rx_batch
, skb
);
318 /* Is the batch large enough to be worthwhile? */
319 if (i
< (queue
->rx_target
/2)) {
320 if (req_prod
> queue
->rx
.sring
->req_prod
)
325 /* Adjust our fill target if we risked running out of buffers. */
326 if (((req_prod
- queue
->rx
.sring
->rsp_prod
) < (queue
->rx_target
/ 4)) &&
327 ((queue
->rx_target
*= 2) > queue
->rx_max_target
))
328 queue
->rx_target
= queue
->rx_max_target
;
332 skb
= __skb_dequeue(&queue
->rx_batch
);
336 skb
->dev
= queue
->info
->netdev
;
338 id
= xennet_rxidx(req_prod
+ i
);
340 BUG_ON(queue
->rx_skbs
[id
]);
341 queue
->rx_skbs
[id
] = skb
;
343 ref
= gnttab_claim_grant_reference(&queue
->gref_rx_head
);
344 BUG_ON((signed short)ref
< 0);
345 queue
->grant_rx_ref
[id
] = ref
;
347 pfn
= page_to_pfn(skb_frag_page(&skb_shinfo(skb
)->frags
[0]));
348 vaddr
= page_address(skb_frag_page(&skb_shinfo(skb
)->frags
[0]));
350 req
= RING_GET_REQUEST(&queue
->rx
, req_prod
+ i
);
351 gnttab_grant_foreign_access_ref(ref
,
352 queue
->info
->xbdev
->otherend_id
,
360 wmb(); /* barrier so backend seens requests */
362 /* Above is a suitable barrier to ensure backend will see requests. */
363 queue
->rx
.req_prod_pvt
= req_prod
+ i
;
365 RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue
->rx
, notify
);
367 notify_remote_via_irq(queue
->rx_irq
);
370 static int xennet_open(struct net_device
*dev
)
372 struct netfront_info
*np
= netdev_priv(dev
);
373 unsigned int num_queues
= dev
->real_num_tx_queues
;
375 struct netfront_queue
*queue
= NULL
;
377 for (i
= 0; i
< num_queues
; ++i
) {
378 queue
= &np
->queues
[i
];
379 napi_enable(&queue
->napi
);
381 spin_lock_bh(&queue
->rx_lock
);
382 if (netif_carrier_ok(dev
)) {
383 xennet_alloc_rx_buffers(queue
);
384 queue
->rx
.sring
->rsp_event
= queue
->rx
.rsp_cons
+ 1;
385 if (RING_HAS_UNCONSUMED_RESPONSES(&queue
->rx
))
386 napi_schedule(&queue
->napi
);
388 spin_unlock_bh(&queue
->rx_lock
);
391 netif_tx_start_all_queues(dev
);
396 static void xennet_tx_buf_gc(struct netfront_queue
*queue
)
402 BUG_ON(!netif_carrier_ok(queue
->info
->netdev
));
405 prod
= queue
->tx
.sring
->rsp_prod
;
406 rmb(); /* Ensure we see responses up to 'rp'. */
408 for (cons
= queue
->tx
.rsp_cons
; cons
!= prod
; cons
++) {
409 struct xen_netif_tx_response
*txrsp
;
411 txrsp
= RING_GET_RESPONSE(&queue
->tx
, cons
);
412 if (txrsp
->status
== XEN_NETIF_RSP_NULL
)
416 skb
= queue
->tx_skbs
[id
].skb
;
417 if (unlikely(gnttab_query_foreign_access(
418 queue
->grant_tx_ref
[id
]) != 0)) {
419 pr_alert("%s: warning -- grant still in use by backend domain\n",
423 gnttab_end_foreign_access_ref(
424 queue
->grant_tx_ref
[id
], GNTMAP_readonly
);
425 gnttab_release_grant_reference(
426 &queue
->gref_tx_head
, queue
->grant_tx_ref
[id
]);
427 queue
->grant_tx_ref
[id
] = GRANT_INVALID_REF
;
428 queue
->grant_tx_page
[id
] = NULL
;
429 add_id_to_freelist(&queue
->tx_skb_freelist
, queue
->tx_skbs
, id
);
430 dev_kfree_skb_irq(skb
);
433 queue
->tx
.rsp_cons
= prod
;
436 * Set a new event, then check for race with update of tx_cons.
437 * Note that it is essential to schedule a callback, no matter
438 * how few buffers are pending. Even if there is space in the
439 * transmit ring, higher layers may be blocked because too much
440 * data is outstanding: in such cases notification from Xen is
441 * likely to be the only kick that we'll get.
443 queue
->tx
.sring
->rsp_event
=
444 prod
+ ((queue
->tx
.sring
->req_prod
- prod
) >> 1) + 1;
445 mb(); /* update shared area */
446 } while ((cons
== prod
) && (prod
!= queue
->tx
.sring
->rsp_prod
));
448 xennet_maybe_wake_tx(queue
);
451 static void xennet_make_frags(struct sk_buff
*skb
, struct netfront_queue
*queue
,
452 struct xen_netif_tx_request
*tx
)
454 char *data
= skb
->data
;
456 RING_IDX prod
= queue
->tx
.req_prod_pvt
;
457 int frags
= skb_shinfo(skb
)->nr_frags
;
458 unsigned int offset
= offset_in_page(data
);
459 unsigned int len
= skb_headlen(skb
);
464 /* While the header overlaps a page boundary (including being
465 larger than a page), split it it into page-sized chunks. */
466 while (len
> PAGE_SIZE
- offset
) {
467 tx
->size
= PAGE_SIZE
- offset
;
468 tx
->flags
|= XEN_NETTXF_more_data
;
473 id
= get_id_from_freelist(&queue
->tx_skb_freelist
, queue
->tx_skbs
);
474 queue
->tx_skbs
[id
].skb
= skb_get(skb
);
475 tx
= RING_GET_REQUEST(&queue
->tx
, prod
++);
477 ref
= gnttab_claim_grant_reference(&queue
->gref_tx_head
);
478 BUG_ON((signed short)ref
< 0);
480 mfn
= virt_to_mfn(data
);
481 gnttab_grant_foreign_access_ref(ref
, queue
->info
->xbdev
->otherend_id
,
482 mfn
, GNTMAP_readonly
);
484 queue
->grant_tx_page
[id
] = virt_to_page(data
);
485 tx
->gref
= queue
->grant_tx_ref
[id
] = ref
;
491 /* Grant backend access to each skb fragment page. */
492 for (i
= 0; i
< frags
; i
++) {
493 skb_frag_t
*frag
= skb_shinfo(skb
)->frags
+ i
;
494 struct page
*page
= skb_frag_page(frag
);
496 len
= skb_frag_size(frag
);
497 offset
= frag
->page_offset
;
499 /* Skip unused frames from start of page */
500 page
+= offset
>> PAGE_SHIFT
;
501 offset
&= ~PAGE_MASK
;
506 bytes
= PAGE_SIZE
- offset
;
510 tx
->flags
|= XEN_NETTXF_more_data
;
512 id
= get_id_from_freelist(&queue
->tx_skb_freelist
,
514 queue
->tx_skbs
[id
].skb
= skb_get(skb
);
515 tx
= RING_GET_REQUEST(&queue
->tx
, prod
++);
517 ref
= gnttab_claim_grant_reference(&queue
->gref_tx_head
);
518 BUG_ON((signed short)ref
< 0);
520 mfn
= pfn_to_mfn(page_to_pfn(page
));
521 gnttab_grant_foreign_access_ref(ref
,
522 queue
->info
->xbdev
->otherend_id
,
523 mfn
, GNTMAP_readonly
);
525 queue
->grant_tx_page
[id
] = page
;
526 tx
->gref
= queue
->grant_tx_ref
[id
] = ref
;
535 if (offset
== PAGE_SIZE
&& len
) {
536 BUG_ON(!PageCompound(page
));
543 queue
->tx
.req_prod_pvt
= prod
;
547 * Count how many ring slots are required to send the frags of this
548 * skb. Each frag might be a compound page.
550 static int xennet_count_skb_frag_slots(struct sk_buff
*skb
)
552 int i
, frags
= skb_shinfo(skb
)->nr_frags
;
555 for (i
= 0; i
< frags
; i
++) {
556 skb_frag_t
*frag
= skb_shinfo(skb
)->frags
+ i
;
557 unsigned long size
= skb_frag_size(frag
);
558 unsigned long offset
= frag
->page_offset
;
560 /* Skip unused frames from start of page */
561 offset
&= ~PAGE_MASK
;
563 pages
+= PFN_UP(offset
+ size
);
569 static u16
xennet_select_queue(struct net_device
*dev
, struct sk_buff
*skb
,
570 void *accel_priv
, select_queue_fallback_t fallback
)
572 unsigned int num_queues
= dev
->real_num_tx_queues
;
576 /* First, check if there is only one queue */
577 if (num_queues
== 1) {
580 hash
= skb_get_hash(skb
);
581 queue_idx
= hash
% num_queues
;
587 static int xennet_start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
590 struct netfront_info
*np
= netdev_priv(dev
);
591 struct netfront_stats
*stats
= this_cpu_ptr(np
->stats
);
592 struct xen_netif_tx_request
*tx
;
593 char *data
= skb
->data
;
599 unsigned int offset
= offset_in_page(data
);
600 unsigned int len
= skb_headlen(skb
);
602 struct netfront_queue
*queue
= NULL
;
603 unsigned int num_queues
= dev
->real_num_tx_queues
;
606 /* Drop the packet if no queues are set up */
609 /* Determine which queue to transmit this SKB on */
610 queue_index
= skb_get_queue_mapping(skb
);
611 queue
= &np
->queues
[queue_index
];
613 /* If skb->len is too big for wire format, drop skb and alert
614 * user about misconfiguration.
616 if (unlikely(skb
->len
> XEN_NETIF_MAX_TX_SIZE
)) {
617 net_alert_ratelimited(
618 "xennet: skb->len = %u, too big for wire format\n",
623 slots
= DIV_ROUND_UP(offset
+ len
, PAGE_SIZE
) +
624 xennet_count_skb_frag_slots(skb
);
625 if (unlikely(slots
> MAX_SKB_FRAGS
+ 1)) {
626 net_dbg_ratelimited("xennet: skb rides the rocket: %d slots, %d bytes\n",
628 if (skb_linearize(skb
))
632 spin_lock_irqsave(&queue
->tx_lock
, flags
);
634 if (unlikely(!netif_carrier_ok(dev
) ||
635 (slots
> 1 && !xennet_can_sg(dev
)) ||
636 netif_needs_gso(dev
, skb
, netif_skb_features(skb
)))) {
637 spin_unlock_irqrestore(&queue
->tx_lock
, flags
);
641 i
= queue
->tx
.req_prod_pvt
;
643 id
= get_id_from_freelist(&queue
->tx_skb_freelist
, queue
->tx_skbs
);
644 queue
->tx_skbs
[id
].skb
= skb
;
646 tx
= RING_GET_REQUEST(&queue
->tx
, i
);
649 ref
= gnttab_claim_grant_reference(&queue
->gref_tx_head
);
650 BUG_ON((signed short)ref
< 0);
651 mfn
= virt_to_mfn(data
);
652 gnttab_grant_foreign_access_ref(
653 ref
, queue
->info
->xbdev
->otherend_id
, mfn
, GNTMAP_readonly
);
654 queue
->grant_tx_page
[id
] = virt_to_page(data
);
655 tx
->gref
= queue
->grant_tx_ref
[id
] = ref
;
660 if (skb
->ip_summed
== CHECKSUM_PARTIAL
)
662 tx
->flags
|= XEN_NETTXF_csum_blank
| XEN_NETTXF_data_validated
;
663 else if (skb
->ip_summed
== CHECKSUM_UNNECESSARY
)
664 /* remote but checksummed. */
665 tx
->flags
|= XEN_NETTXF_data_validated
;
667 if (skb_shinfo(skb
)->gso_size
) {
668 struct xen_netif_extra_info
*gso
;
670 gso
= (struct xen_netif_extra_info
*)
671 RING_GET_REQUEST(&queue
->tx
, ++i
);
673 tx
->flags
|= XEN_NETTXF_extra_info
;
675 gso
->u
.gso
.size
= skb_shinfo(skb
)->gso_size
;
676 gso
->u
.gso
.type
= (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
) ?
677 XEN_NETIF_GSO_TYPE_TCPV6
:
678 XEN_NETIF_GSO_TYPE_TCPV4
;
680 gso
->u
.gso
.features
= 0;
682 gso
->type
= XEN_NETIF_EXTRA_TYPE_GSO
;
686 queue
->tx
.req_prod_pvt
= i
+ 1;
688 xennet_make_frags(skb
, queue
, tx
);
691 RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue
->tx
, notify
);
693 notify_remote_via_irq(queue
->tx_irq
);
695 u64_stats_update_begin(&stats
->syncp
);
696 stats
->tx_bytes
+= skb
->len
;
698 u64_stats_update_end(&stats
->syncp
);
700 /* Note: It is not safe to access skb after xennet_tx_buf_gc()! */
701 xennet_tx_buf_gc(queue
);
703 if (!netfront_tx_slot_available(queue
))
704 netif_tx_stop_queue(netdev_get_tx_queue(dev
, queue
->id
));
706 spin_unlock_irqrestore(&queue
->tx_lock
, flags
);
711 dev
->stats
.tx_dropped
++;
712 dev_kfree_skb_any(skb
);
716 static int xennet_close(struct net_device
*dev
)
718 struct netfront_info
*np
= netdev_priv(dev
);
719 unsigned int num_queues
= dev
->real_num_tx_queues
;
721 struct netfront_queue
*queue
;
722 netif_tx_stop_all_queues(np
->netdev
);
723 for (i
= 0; i
< num_queues
; ++i
) {
724 queue
= &np
->queues
[i
];
725 napi_disable(&queue
->napi
);
730 static void xennet_move_rx_slot(struct netfront_queue
*queue
, struct sk_buff
*skb
,
733 int new = xennet_rxidx(queue
->rx
.req_prod_pvt
);
735 BUG_ON(queue
->rx_skbs
[new]);
736 queue
->rx_skbs
[new] = skb
;
737 queue
->grant_rx_ref
[new] = ref
;
738 RING_GET_REQUEST(&queue
->rx
, queue
->rx
.req_prod_pvt
)->id
= new;
739 RING_GET_REQUEST(&queue
->rx
, queue
->rx
.req_prod_pvt
)->gref
= ref
;
740 queue
->rx
.req_prod_pvt
++;
743 static int xennet_get_extras(struct netfront_queue
*queue
,
744 struct xen_netif_extra_info
*extras
,
748 struct xen_netif_extra_info
*extra
;
749 struct device
*dev
= &queue
->info
->netdev
->dev
;
750 RING_IDX cons
= queue
->rx
.rsp_cons
;
757 if (unlikely(cons
+ 1 == rp
)) {
759 dev_warn(dev
, "Missing extra info\n");
764 extra
= (struct xen_netif_extra_info
*)
765 RING_GET_RESPONSE(&queue
->rx
, ++cons
);
767 if (unlikely(!extra
->type
||
768 extra
->type
>= XEN_NETIF_EXTRA_TYPE_MAX
)) {
770 dev_warn(dev
, "Invalid extra type: %d\n",
774 memcpy(&extras
[extra
->type
- 1], extra
,
778 skb
= xennet_get_rx_skb(queue
, cons
);
779 ref
= xennet_get_rx_ref(queue
, cons
);
780 xennet_move_rx_slot(queue
, skb
, ref
);
781 } while (extra
->flags
& XEN_NETIF_EXTRA_FLAG_MORE
);
783 queue
->rx
.rsp_cons
= cons
;
787 static int xennet_get_responses(struct netfront_queue
*queue
,
788 struct netfront_rx_info
*rinfo
, RING_IDX rp
,
789 struct sk_buff_head
*list
)
791 struct xen_netif_rx_response
*rx
= &rinfo
->rx
;
792 struct xen_netif_extra_info
*extras
= rinfo
->extras
;
793 struct device
*dev
= &queue
->info
->netdev
->dev
;
794 RING_IDX cons
= queue
->rx
.rsp_cons
;
795 struct sk_buff
*skb
= xennet_get_rx_skb(queue
, cons
);
796 grant_ref_t ref
= xennet_get_rx_ref(queue
, cons
);
797 int max
= MAX_SKB_FRAGS
+ (rx
->status
<= RX_COPY_THRESHOLD
);
802 if (rx
->flags
& XEN_NETRXF_extra_info
) {
803 err
= xennet_get_extras(queue
, extras
, rp
);
804 cons
= queue
->rx
.rsp_cons
;
808 if (unlikely(rx
->status
< 0 ||
809 rx
->offset
+ rx
->status
> PAGE_SIZE
)) {
811 dev_warn(dev
, "rx->offset: %x, size: %u\n",
812 rx
->offset
, rx
->status
);
813 xennet_move_rx_slot(queue
, skb
, ref
);
819 * This definitely indicates a bug, either in this driver or in
820 * the backend driver. In future this should flag the bad
821 * situation to the system controller to reboot the backend.
823 if (ref
== GRANT_INVALID_REF
) {
825 dev_warn(dev
, "Bad rx response id %d.\n",
831 ret
= gnttab_end_foreign_access_ref(ref
, 0);
834 gnttab_release_grant_reference(&queue
->gref_rx_head
, ref
);
836 __skb_queue_tail(list
, skb
);
839 if (!(rx
->flags
& XEN_NETRXF_more_data
))
842 if (cons
+ slots
== rp
) {
844 dev_warn(dev
, "Need more slots\n");
849 rx
= RING_GET_RESPONSE(&queue
->rx
, cons
+ slots
);
850 skb
= xennet_get_rx_skb(queue
, cons
+ slots
);
851 ref
= xennet_get_rx_ref(queue
, cons
+ slots
);
855 if (unlikely(slots
> max
)) {
857 dev_warn(dev
, "Too many slots\n");
862 queue
->rx
.rsp_cons
= cons
+ slots
;
867 static int xennet_set_skb_gso(struct sk_buff
*skb
,
868 struct xen_netif_extra_info
*gso
)
870 if (!gso
->u
.gso
.size
) {
872 pr_warn("GSO size must not be zero\n");
876 if (gso
->u
.gso
.type
!= XEN_NETIF_GSO_TYPE_TCPV4
&&
877 gso
->u
.gso
.type
!= XEN_NETIF_GSO_TYPE_TCPV6
) {
879 pr_warn("Bad GSO type %d\n", gso
->u
.gso
.type
);
883 skb_shinfo(skb
)->gso_size
= gso
->u
.gso
.size
;
884 skb_shinfo(skb
)->gso_type
=
885 (gso
->u
.gso
.type
== XEN_NETIF_GSO_TYPE_TCPV4
) ?
889 /* Header must be checked, and gso_segs computed. */
890 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
891 skb_shinfo(skb
)->gso_segs
= 0;
896 static RING_IDX
xennet_fill_frags(struct netfront_queue
*queue
,
898 struct sk_buff_head
*list
)
900 struct skb_shared_info
*shinfo
= skb_shinfo(skb
);
901 RING_IDX cons
= queue
->rx
.rsp_cons
;
902 struct sk_buff
*nskb
;
904 while ((nskb
= __skb_dequeue(list
))) {
905 struct xen_netif_rx_response
*rx
=
906 RING_GET_RESPONSE(&queue
->rx
, ++cons
);
907 skb_frag_t
*nfrag
= &skb_shinfo(nskb
)->frags
[0];
909 if (shinfo
->nr_frags
== MAX_SKB_FRAGS
) {
910 unsigned int pull_to
= NETFRONT_SKB_CB(skb
)->pull_to
;
912 BUG_ON(pull_to
<= skb_headlen(skb
));
913 __pskb_pull_tail(skb
, pull_to
- skb_headlen(skb
));
915 BUG_ON(shinfo
->nr_frags
>= MAX_SKB_FRAGS
);
917 skb_add_rx_frag(skb
, shinfo
->nr_frags
, skb_frag_page(nfrag
),
918 rx
->offset
, rx
->status
, PAGE_SIZE
);
920 skb_shinfo(nskb
)->nr_frags
= 0;
927 static int checksum_setup(struct net_device
*dev
, struct sk_buff
*skb
)
929 bool recalculate_partial_csum
= false;
932 * A GSO SKB must be CHECKSUM_PARTIAL. However some buggy
933 * peers can fail to set NETRXF_csum_blank when sending a GSO
934 * frame. In this case force the SKB to CHECKSUM_PARTIAL and
935 * recalculate the partial checksum.
937 if (skb
->ip_summed
!= CHECKSUM_PARTIAL
&& skb_is_gso(skb
)) {
938 struct netfront_info
*np
= netdev_priv(dev
);
939 atomic_inc(&np
->rx_gso_checksum_fixup
);
940 skb
->ip_summed
= CHECKSUM_PARTIAL
;
941 recalculate_partial_csum
= true;
944 /* A non-CHECKSUM_PARTIAL SKB does not require setup. */
945 if (skb
->ip_summed
!= CHECKSUM_PARTIAL
)
948 return skb_checksum_setup(skb
, recalculate_partial_csum
);
951 static int handle_incoming_queue(struct netfront_queue
*queue
,
952 struct sk_buff_head
*rxq
)
954 struct netfront_stats
*stats
= this_cpu_ptr(queue
->info
->stats
);
955 int packets_dropped
= 0;
958 while ((skb
= __skb_dequeue(rxq
)) != NULL
) {
959 int pull_to
= NETFRONT_SKB_CB(skb
)->pull_to
;
961 if (pull_to
> skb_headlen(skb
))
962 __pskb_pull_tail(skb
, pull_to
- skb_headlen(skb
));
964 /* Ethernet work: Delayed to here as it peeks the header. */
965 skb
->protocol
= eth_type_trans(skb
, queue
->info
->netdev
);
966 skb_reset_network_header(skb
);
968 if (checksum_setup(queue
->info
->netdev
, skb
)) {
971 queue
->info
->netdev
->stats
.rx_errors
++;
975 u64_stats_update_begin(&stats
->syncp
);
977 stats
->rx_bytes
+= skb
->len
;
978 u64_stats_update_end(&stats
->syncp
);
981 napi_gro_receive(&queue
->napi
, skb
);
984 return packets_dropped
;
987 static int xennet_poll(struct napi_struct
*napi
, int budget
)
989 struct netfront_queue
*queue
= container_of(napi
, struct netfront_queue
, napi
);
990 struct net_device
*dev
= queue
->info
->netdev
;
992 struct netfront_rx_info rinfo
;
993 struct xen_netif_rx_response
*rx
= &rinfo
.rx
;
994 struct xen_netif_extra_info
*extras
= rinfo
.extras
;
997 struct sk_buff_head rxq
;
998 struct sk_buff_head errq
;
999 struct sk_buff_head tmpq
;
1000 unsigned long flags
;
1003 spin_lock(&queue
->rx_lock
);
1005 skb_queue_head_init(&rxq
);
1006 skb_queue_head_init(&errq
);
1007 skb_queue_head_init(&tmpq
);
1009 rp
= queue
->rx
.sring
->rsp_prod
;
1010 rmb(); /* Ensure we see queued responses up to 'rp'. */
1012 i
= queue
->rx
.rsp_cons
;
1014 while ((i
!= rp
) && (work_done
< budget
)) {
1015 memcpy(rx
, RING_GET_RESPONSE(&queue
->rx
, i
), sizeof(*rx
));
1016 memset(extras
, 0, sizeof(rinfo
.extras
));
1018 err
= xennet_get_responses(queue
, &rinfo
, rp
, &tmpq
);
1020 if (unlikely(err
)) {
1022 while ((skb
= __skb_dequeue(&tmpq
)))
1023 __skb_queue_tail(&errq
, skb
);
1024 dev
->stats
.rx_errors
++;
1025 i
= queue
->rx
.rsp_cons
;
1029 skb
= __skb_dequeue(&tmpq
);
1031 if (extras
[XEN_NETIF_EXTRA_TYPE_GSO
- 1].type
) {
1032 struct xen_netif_extra_info
*gso
;
1033 gso
= &extras
[XEN_NETIF_EXTRA_TYPE_GSO
- 1];
1035 if (unlikely(xennet_set_skb_gso(skb
, gso
))) {
1036 __skb_queue_head(&tmpq
, skb
);
1037 queue
->rx
.rsp_cons
+= skb_queue_len(&tmpq
);
1042 NETFRONT_SKB_CB(skb
)->pull_to
= rx
->status
;
1043 if (NETFRONT_SKB_CB(skb
)->pull_to
> RX_COPY_THRESHOLD
)
1044 NETFRONT_SKB_CB(skb
)->pull_to
= RX_COPY_THRESHOLD
;
1046 skb_shinfo(skb
)->frags
[0].page_offset
= rx
->offset
;
1047 skb_frag_size_set(&skb_shinfo(skb
)->frags
[0], rx
->status
);
1048 skb
->data_len
= rx
->status
;
1049 skb
->len
+= rx
->status
;
1051 i
= xennet_fill_frags(queue
, skb
, &tmpq
);
1053 if (rx
->flags
& XEN_NETRXF_csum_blank
)
1054 skb
->ip_summed
= CHECKSUM_PARTIAL
;
1055 else if (rx
->flags
& XEN_NETRXF_data_validated
)
1056 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
1058 __skb_queue_tail(&rxq
, skb
);
1060 queue
->rx
.rsp_cons
= ++i
;
1064 __skb_queue_purge(&errq
);
1066 work_done
-= handle_incoming_queue(queue
, &rxq
);
1068 /* If we get a callback with very few responses, reduce fill target. */
1069 /* NB. Note exponential increase, linear decrease. */
1070 if (((queue
->rx
.req_prod_pvt
- queue
->rx
.sring
->rsp_prod
) >
1071 ((3*queue
->rx_target
) / 4)) &&
1072 (--queue
->rx_target
< queue
->rx_min_target
))
1073 queue
->rx_target
= queue
->rx_min_target
;
1075 xennet_alloc_rx_buffers(queue
);
1077 if (work_done
< budget
) {
1080 napi_gro_flush(napi
, false);
1082 local_irq_save(flags
);
1084 RING_FINAL_CHECK_FOR_RESPONSES(&queue
->rx
, more_to_do
);
1086 __napi_complete(napi
);
1088 local_irq_restore(flags
);
1091 spin_unlock(&queue
->rx_lock
);
1096 static int xennet_change_mtu(struct net_device
*dev
, int mtu
)
1098 int max
= xennet_can_sg(dev
) ?
1099 XEN_NETIF_MAX_TX_SIZE
- MAX_TCP_HEADER
: ETH_DATA_LEN
;
1107 static struct rtnl_link_stats64
*xennet_get_stats64(struct net_device
*dev
,
1108 struct rtnl_link_stats64
*tot
)
1110 struct netfront_info
*np
= netdev_priv(dev
);
1113 for_each_possible_cpu(cpu
) {
1114 struct netfront_stats
*stats
= per_cpu_ptr(np
->stats
, cpu
);
1115 u64 rx_packets
, rx_bytes
, tx_packets
, tx_bytes
;
1119 start
= u64_stats_fetch_begin_irq(&stats
->syncp
);
1121 rx_packets
= stats
->rx_packets
;
1122 tx_packets
= stats
->tx_packets
;
1123 rx_bytes
= stats
->rx_bytes
;
1124 tx_bytes
= stats
->tx_bytes
;
1125 } while (u64_stats_fetch_retry_irq(&stats
->syncp
, start
));
1127 tot
->rx_packets
+= rx_packets
;
1128 tot
->tx_packets
+= tx_packets
;
1129 tot
->rx_bytes
+= rx_bytes
;
1130 tot
->tx_bytes
+= tx_bytes
;
1133 tot
->rx_errors
= dev
->stats
.rx_errors
;
1134 tot
->tx_dropped
= dev
->stats
.tx_dropped
;
1139 static void xennet_release_tx_bufs(struct netfront_queue
*queue
)
1141 struct sk_buff
*skb
;
1144 for (i
= 0; i
< NET_TX_RING_SIZE
; i
++) {
1145 /* Skip over entries which are actually freelist references */
1146 if (skb_entry_is_link(&queue
->tx_skbs
[i
]))
1149 skb
= queue
->tx_skbs
[i
].skb
;
1150 get_page(queue
->grant_tx_page
[i
]);
1151 gnttab_end_foreign_access(queue
->grant_tx_ref
[i
],
1153 (unsigned long)page_address(queue
->grant_tx_page
[i
]));
1154 queue
->grant_tx_page
[i
] = NULL
;
1155 queue
->grant_tx_ref
[i
] = GRANT_INVALID_REF
;
1156 add_id_to_freelist(&queue
->tx_skb_freelist
, queue
->tx_skbs
, i
);
1157 dev_kfree_skb_irq(skb
);
1161 static void xennet_release_rx_bufs(struct netfront_queue
*queue
)
1165 spin_lock_bh(&queue
->rx_lock
);
1167 for (id
= 0; id
< NET_RX_RING_SIZE
; id
++) {
1168 struct sk_buff
*skb
;
1171 skb
= queue
->rx_skbs
[id
];
1175 ref
= queue
->grant_rx_ref
[id
];
1176 if (ref
== GRANT_INVALID_REF
)
1179 page
= skb_frag_page(&skb_shinfo(skb
)->frags
[0]);
1181 /* gnttab_end_foreign_access() needs a page ref until
1182 * foreign access is ended (which may be deferred).
1185 gnttab_end_foreign_access(ref
, 0,
1186 (unsigned long)page_address(page
));
1187 queue
->grant_rx_ref
[id
] = GRANT_INVALID_REF
;
1192 spin_unlock_bh(&queue
->rx_lock
);
1195 static netdev_features_t
xennet_fix_features(struct net_device
*dev
,
1196 netdev_features_t features
)
1198 struct netfront_info
*np
= netdev_priv(dev
);
1201 if (features
& NETIF_F_SG
) {
1202 if (xenbus_scanf(XBT_NIL
, np
->xbdev
->otherend
, "feature-sg",
1207 features
&= ~NETIF_F_SG
;
1210 if (features
& NETIF_F_IPV6_CSUM
) {
1211 if (xenbus_scanf(XBT_NIL
, np
->xbdev
->otherend
,
1212 "feature-ipv6-csum-offload", "%d", &val
) < 0)
1216 features
&= ~NETIF_F_IPV6_CSUM
;
1219 if (features
& NETIF_F_TSO
) {
1220 if (xenbus_scanf(XBT_NIL
, np
->xbdev
->otherend
,
1221 "feature-gso-tcpv4", "%d", &val
) < 0)
1225 features
&= ~NETIF_F_TSO
;
1228 if (features
& NETIF_F_TSO6
) {
1229 if (xenbus_scanf(XBT_NIL
, np
->xbdev
->otherend
,
1230 "feature-gso-tcpv6", "%d", &val
) < 0)
1234 features
&= ~NETIF_F_TSO6
;
1240 static int xennet_set_features(struct net_device
*dev
,
1241 netdev_features_t features
)
1243 if (!(features
& NETIF_F_SG
) && dev
->mtu
> ETH_DATA_LEN
) {
1244 netdev_info(dev
, "Reducing MTU because no SG offload");
1245 dev
->mtu
= ETH_DATA_LEN
;
1251 static irqreturn_t
xennet_tx_interrupt(int irq
, void *dev_id
)
1253 struct netfront_queue
*queue
= dev_id
;
1254 unsigned long flags
;
1256 spin_lock_irqsave(&queue
->tx_lock
, flags
);
1257 xennet_tx_buf_gc(queue
);
1258 spin_unlock_irqrestore(&queue
->tx_lock
, flags
);
1263 static irqreturn_t
xennet_rx_interrupt(int irq
, void *dev_id
)
1265 struct netfront_queue
*queue
= dev_id
;
1266 struct net_device
*dev
= queue
->info
->netdev
;
1268 if (likely(netif_carrier_ok(dev
) &&
1269 RING_HAS_UNCONSUMED_RESPONSES(&queue
->rx
)))
1270 napi_schedule(&queue
->napi
);
1275 static irqreturn_t
xennet_interrupt(int irq
, void *dev_id
)
1277 xennet_tx_interrupt(irq
, dev_id
);
1278 xennet_rx_interrupt(irq
, dev_id
);
1282 #ifdef CONFIG_NET_POLL_CONTROLLER
1283 static void xennet_poll_controller(struct net_device
*dev
)
1285 /* Poll each queue */
1286 struct netfront_info
*info
= netdev_priv(dev
);
1287 unsigned int num_queues
= dev
->real_num_tx_queues
;
1289 for (i
= 0; i
< num_queues
; ++i
)
1290 xennet_interrupt(0, &info
->queues
[i
]);
1294 static const struct net_device_ops xennet_netdev_ops
= {
1295 .ndo_open
= xennet_open
,
1296 .ndo_stop
= xennet_close
,
1297 .ndo_start_xmit
= xennet_start_xmit
,
1298 .ndo_change_mtu
= xennet_change_mtu
,
1299 .ndo_get_stats64
= xennet_get_stats64
,
1300 .ndo_set_mac_address
= eth_mac_addr
,
1301 .ndo_validate_addr
= eth_validate_addr
,
1302 .ndo_fix_features
= xennet_fix_features
,
1303 .ndo_set_features
= xennet_set_features
,
1304 .ndo_select_queue
= xennet_select_queue
,
1305 #ifdef CONFIG_NET_POLL_CONTROLLER
1306 .ndo_poll_controller
= xennet_poll_controller
,
1310 static struct net_device
*xennet_create_dev(struct xenbus_device
*dev
)
1313 struct net_device
*netdev
;
1314 struct netfront_info
*np
;
1316 netdev
= alloc_etherdev_mq(sizeof(struct netfront_info
), xennet_max_queues
);
1318 return ERR_PTR(-ENOMEM
);
1320 np
= netdev_priv(netdev
);
1323 /* No need to use rtnl_lock() before the call below as it
1324 * happens before register_netdev().
1326 netif_set_real_num_tx_queues(netdev
, 0);
1330 np
->stats
= netdev_alloc_pcpu_stats(struct netfront_stats
);
1331 if (np
->stats
== NULL
)
1334 netdev
->netdev_ops
= &xennet_netdev_ops
;
1336 netdev
->features
= NETIF_F_IP_CSUM
| NETIF_F_RXCSUM
|
1338 netdev
->hw_features
= NETIF_F_SG
|
1340 NETIF_F_TSO
| NETIF_F_TSO6
;
1343 * Assume that all hw features are available for now. This set
1344 * will be adjusted by the call to netdev_update_features() in
1345 * xennet_connect() which is the earliest point where we can
1346 * negotiate with the backend regarding supported features.
1348 netdev
->features
|= netdev
->hw_features
;
1350 netdev
->ethtool_ops
= &xennet_ethtool_ops
;
1351 SET_NETDEV_DEV(netdev
, &dev
->dev
);
1353 netif_set_gso_max_size(netdev
, XEN_NETIF_MAX_TX_SIZE
- MAX_TCP_HEADER
);
1355 np
->netdev
= netdev
;
1357 netif_carrier_off(netdev
);
1362 free_netdev(netdev
);
1363 return ERR_PTR(err
);
1367 * Entry point to this code when a new device is created. Allocate the basic
1368 * structures and the ring buffers for communication with the backend, and
1369 * inform the backend of the appropriate details for those.
1371 static int netfront_probe(struct xenbus_device
*dev
,
1372 const struct xenbus_device_id
*id
)
1375 struct net_device
*netdev
;
1376 struct netfront_info
*info
;
1378 netdev
= xennet_create_dev(dev
);
1379 if (IS_ERR(netdev
)) {
1380 err
= PTR_ERR(netdev
);
1381 xenbus_dev_fatal(dev
, err
, "creating netdev");
1385 info
= netdev_priv(netdev
);
1386 dev_set_drvdata(&dev
->dev
, info
);
1388 err
= register_netdev(info
->netdev
);
1390 pr_warn("%s: register_netdev err=%d\n", __func__
, err
);
1394 err
= xennet_sysfs_addif(info
->netdev
);
1396 unregister_netdev(info
->netdev
);
1397 pr_warn("%s: add sysfs failed err=%d\n", __func__
, err
);
1404 free_netdev(netdev
);
1405 dev_set_drvdata(&dev
->dev
, NULL
);
1409 static void xennet_end_access(int ref
, void *page
)
1411 /* This frees the page as a side-effect */
1412 if (ref
!= GRANT_INVALID_REF
)
1413 gnttab_end_foreign_access(ref
, 0, (unsigned long)page
);
1416 static void xennet_disconnect_backend(struct netfront_info
*info
)
1419 unsigned int num_queues
= info
->netdev
->real_num_tx_queues
;
1421 netif_carrier_off(info
->netdev
);
1423 for (i
= 0; i
< num_queues
; ++i
) {
1424 struct netfront_queue
*queue
= &info
->queues
[i
];
1426 if (queue
->tx_irq
&& (queue
->tx_irq
== queue
->rx_irq
))
1427 unbind_from_irqhandler(queue
->tx_irq
, queue
);
1428 if (queue
->tx_irq
&& (queue
->tx_irq
!= queue
->rx_irq
)) {
1429 unbind_from_irqhandler(queue
->tx_irq
, queue
);
1430 unbind_from_irqhandler(queue
->rx_irq
, queue
);
1432 queue
->tx_evtchn
= queue
->rx_evtchn
= 0;
1433 queue
->tx_irq
= queue
->rx_irq
= 0;
1435 napi_synchronize(&queue
->napi
);
1437 xennet_release_tx_bufs(queue
);
1438 xennet_release_rx_bufs(queue
);
1439 gnttab_free_grant_references(queue
->gref_tx_head
);
1440 gnttab_free_grant_references(queue
->gref_rx_head
);
1442 /* End access and free the pages */
1443 xennet_end_access(queue
->tx_ring_ref
, queue
->tx
.sring
);
1444 xennet_end_access(queue
->rx_ring_ref
, queue
->rx
.sring
);
1446 queue
->tx_ring_ref
= GRANT_INVALID_REF
;
1447 queue
->rx_ring_ref
= GRANT_INVALID_REF
;
1448 queue
->tx
.sring
= NULL
;
1449 queue
->rx
.sring
= NULL
;
1454 * We are reconnecting to the backend, due to a suspend/resume, or a backend
1455 * driver restart. We tear down our netif structure and recreate it, but
1456 * leave the device-layer structures intact so that this is transparent to the
1457 * rest of the kernel.
1459 static int netfront_resume(struct xenbus_device
*dev
)
1461 struct netfront_info
*info
= dev_get_drvdata(&dev
->dev
);
1463 dev_dbg(&dev
->dev
, "%s\n", dev
->nodename
);
1465 xennet_disconnect_backend(info
);
1469 static int xen_net_read_mac(struct xenbus_device
*dev
, u8 mac
[])
1471 char *s
, *e
, *macstr
;
1474 macstr
= s
= xenbus_read(XBT_NIL
, dev
->nodename
, "mac", NULL
);
1476 return PTR_ERR(macstr
);
1478 for (i
= 0; i
< ETH_ALEN
; i
++) {
1479 mac
[i
] = simple_strtoul(s
, &e
, 16);
1480 if ((s
== e
) || (*e
!= ((i
== ETH_ALEN
-1) ? '\0' : ':'))) {
1491 static int setup_netfront_single(struct netfront_queue
*queue
)
1495 err
= xenbus_alloc_evtchn(queue
->info
->xbdev
, &queue
->tx_evtchn
);
1499 err
= bind_evtchn_to_irqhandler(queue
->tx_evtchn
,
1501 0, queue
->info
->netdev
->name
, queue
);
1504 queue
->rx_evtchn
= queue
->tx_evtchn
;
1505 queue
->rx_irq
= queue
->tx_irq
= err
;
1510 xenbus_free_evtchn(queue
->info
->xbdev
, queue
->tx_evtchn
);
1511 queue
->tx_evtchn
= 0;
1516 static int setup_netfront_split(struct netfront_queue
*queue
)
1520 err
= xenbus_alloc_evtchn(queue
->info
->xbdev
, &queue
->tx_evtchn
);
1523 err
= xenbus_alloc_evtchn(queue
->info
->xbdev
, &queue
->rx_evtchn
);
1525 goto alloc_rx_evtchn_fail
;
1527 snprintf(queue
->tx_irq_name
, sizeof(queue
->tx_irq_name
),
1528 "%s-tx", queue
->name
);
1529 err
= bind_evtchn_to_irqhandler(queue
->tx_evtchn
,
1530 xennet_tx_interrupt
,
1531 0, queue
->tx_irq_name
, queue
);
1534 queue
->tx_irq
= err
;
1536 snprintf(queue
->rx_irq_name
, sizeof(queue
->rx_irq_name
),
1537 "%s-rx", queue
->name
);
1538 err
= bind_evtchn_to_irqhandler(queue
->rx_evtchn
,
1539 xennet_rx_interrupt
,
1540 0, queue
->rx_irq_name
, queue
);
1543 queue
->rx_irq
= err
;
1548 unbind_from_irqhandler(queue
->tx_irq
, queue
);
1551 xenbus_free_evtchn(queue
->info
->xbdev
, queue
->rx_evtchn
);
1552 queue
->rx_evtchn
= 0;
1553 alloc_rx_evtchn_fail
:
1554 xenbus_free_evtchn(queue
->info
->xbdev
, queue
->tx_evtchn
);
1555 queue
->tx_evtchn
= 0;
1560 static int setup_netfront(struct xenbus_device
*dev
,
1561 struct netfront_queue
*queue
, unsigned int feature_split_evtchn
)
1563 struct xen_netif_tx_sring
*txs
;
1564 struct xen_netif_rx_sring
*rxs
;
1567 queue
->tx_ring_ref
= GRANT_INVALID_REF
;
1568 queue
->rx_ring_ref
= GRANT_INVALID_REF
;
1569 queue
->rx
.sring
= NULL
;
1570 queue
->tx
.sring
= NULL
;
1572 txs
= (struct xen_netif_tx_sring
*)get_zeroed_page(GFP_NOIO
| __GFP_HIGH
);
1575 xenbus_dev_fatal(dev
, err
, "allocating tx ring page");
1578 SHARED_RING_INIT(txs
);
1579 FRONT_RING_INIT(&queue
->tx
, txs
, PAGE_SIZE
);
1581 err
= xenbus_grant_ring(dev
, virt_to_mfn(txs
));
1583 goto grant_tx_ring_fail
;
1584 queue
->tx_ring_ref
= err
;
1586 rxs
= (struct xen_netif_rx_sring
*)get_zeroed_page(GFP_NOIO
| __GFP_HIGH
);
1589 xenbus_dev_fatal(dev
, err
, "allocating rx ring page");
1590 goto alloc_rx_ring_fail
;
1592 SHARED_RING_INIT(rxs
);
1593 FRONT_RING_INIT(&queue
->rx
, rxs
, PAGE_SIZE
);
1595 err
= xenbus_grant_ring(dev
, virt_to_mfn(rxs
));
1597 goto grant_rx_ring_fail
;
1598 queue
->rx_ring_ref
= err
;
1600 if (feature_split_evtchn
)
1601 err
= setup_netfront_split(queue
);
1602 /* setup single event channel if
1603 * a) feature-split-event-channels == 0
1604 * b) feature-split-event-channels == 1 but failed to setup
1606 if (!feature_split_evtchn
|| (feature_split_evtchn
&& err
))
1607 err
= setup_netfront_single(queue
);
1610 goto alloc_evtchn_fail
;
1614 /* If we fail to setup netfront, it is safe to just revoke access to
1615 * granted pages because backend is not accessing it at this point.
1618 gnttab_end_foreign_access_ref(queue
->rx_ring_ref
, 0);
1620 free_page((unsigned long)rxs
);
1622 gnttab_end_foreign_access_ref(queue
->tx_ring_ref
, 0);
1624 free_page((unsigned long)txs
);
1629 /* Queue-specific initialisation
1630 * This used to be done in xennet_create_dev() but must now
1633 static int xennet_init_queue(struct netfront_queue
*queue
)
1638 spin_lock_init(&queue
->tx_lock
);
1639 spin_lock_init(&queue
->rx_lock
);
1641 skb_queue_head_init(&queue
->rx_batch
);
1642 queue
->rx_target
= RX_DFL_MIN_TARGET
;
1643 queue
->rx_min_target
= RX_DFL_MIN_TARGET
;
1644 queue
->rx_max_target
= RX_MAX_TARGET
;
1646 init_timer(&queue
->rx_refill_timer
);
1647 queue
->rx_refill_timer
.data
= (unsigned long)queue
;
1648 queue
->rx_refill_timer
.function
= rx_refill_timeout
;
1650 snprintf(queue
->name
, sizeof(queue
->name
), "%s-q%u",
1651 queue
->info
->netdev
->name
, queue
->id
);
1653 /* Initialise tx_skbs as a free chain containing every entry. */
1654 queue
->tx_skb_freelist
= 0;
1655 for (i
= 0; i
< NET_TX_RING_SIZE
; i
++) {
1656 skb_entry_set_link(&queue
->tx_skbs
[i
], i
+1);
1657 queue
->grant_tx_ref
[i
] = GRANT_INVALID_REF
;
1658 queue
->grant_tx_page
[i
] = NULL
;
1661 /* Clear out rx_skbs */
1662 for (i
= 0; i
< NET_RX_RING_SIZE
; i
++) {
1663 queue
->rx_skbs
[i
] = NULL
;
1664 queue
->grant_rx_ref
[i
] = GRANT_INVALID_REF
;
1667 /* A grant for every tx ring slot */
1668 if (gnttab_alloc_grant_references(TX_MAX_TARGET
,
1669 &queue
->gref_tx_head
) < 0) {
1670 pr_alert("can't alloc tx grant refs\n");
1675 /* A grant for every rx ring slot */
1676 if (gnttab_alloc_grant_references(RX_MAX_TARGET
,
1677 &queue
->gref_rx_head
) < 0) {
1678 pr_alert("can't alloc rx grant refs\n");
1686 gnttab_free_grant_references(queue
->gref_tx_head
);
1691 static int write_queue_xenstore_keys(struct netfront_queue
*queue
,
1692 struct xenbus_transaction
*xbt
, int write_hierarchical
)
1694 /* Write the queue-specific keys into XenStore in the traditional
1695 * way for a single queue, or in a queue subkeys for multiple
1698 struct xenbus_device
*dev
= queue
->info
->xbdev
;
1700 const char *message
;
1704 /* Choose the correct place to write the keys */
1705 if (write_hierarchical
) {
1706 pathsize
= strlen(dev
->nodename
) + 10;
1707 path
= kzalloc(pathsize
, GFP_KERNEL
);
1710 message
= "out of memory while writing ring references";
1713 snprintf(path
, pathsize
, "%s/queue-%u",
1714 dev
->nodename
, queue
->id
);
1716 path
= (char *)dev
->nodename
;
1719 /* Write ring references */
1720 err
= xenbus_printf(*xbt
, path
, "tx-ring-ref", "%u",
1721 queue
->tx_ring_ref
);
1723 message
= "writing tx-ring-ref";
1727 err
= xenbus_printf(*xbt
, path
, "rx-ring-ref", "%u",
1728 queue
->rx_ring_ref
);
1730 message
= "writing rx-ring-ref";
1734 /* Write event channels; taking into account both shared
1735 * and split event channel scenarios.
1737 if (queue
->tx_evtchn
== queue
->rx_evtchn
) {
1738 /* Shared event channel */
1739 err
= xenbus_printf(*xbt
, path
,
1740 "event-channel", "%u", queue
->tx_evtchn
);
1742 message
= "writing event-channel";
1746 /* Split event channels */
1747 err
= xenbus_printf(*xbt
, path
,
1748 "event-channel-tx", "%u", queue
->tx_evtchn
);
1750 message
= "writing event-channel-tx";
1754 err
= xenbus_printf(*xbt
, path
,
1755 "event-channel-rx", "%u", queue
->rx_evtchn
);
1757 message
= "writing event-channel-rx";
1762 if (write_hierarchical
)
1767 if (write_hierarchical
)
1769 xenbus_dev_fatal(dev
, err
, "%s", message
);
1773 static void xennet_destroy_queues(struct netfront_info
*info
)
1779 for (i
= 0; i
< info
->netdev
->real_num_tx_queues
; i
++) {
1780 struct netfront_queue
*queue
= &info
->queues
[i
];
1782 if (netif_running(info
->netdev
))
1783 napi_disable(&queue
->napi
);
1784 netif_napi_del(&queue
->napi
);
1789 kfree(info
->queues
);
1790 info
->queues
= NULL
;
1793 static int xennet_create_queues(struct netfront_info
*info
,
1794 unsigned int num_queues
)
1799 info
->queues
= kcalloc(num_queues
, sizeof(struct netfront_queue
),
1806 for (i
= 0; i
< num_queues
; i
++) {
1807 struct netfront_queue
*queue
= &info
->queues
[i
];
1812 ret
= xennet_init_queue(queue
);
1814 dev_warn(&info
->netdev
->dev
,
1815 "only created %d queues\n", i
);
1820 netif_napi_add(queue
->info
->netdev
, &queue
->napi
,
1822 if (netif_running(info
->netdev
))
1823 napi_enable(&queue
->napi
);
1826 netif_set_real_num_tx_queues(info
->netdev
, num_queues
);
1830 if (num_queues
== 0) {
1831 dev_err(&info
->netdev
->dev
, "no queues\n");
1837 /* Common code used when first setting up, and when resuming. */
1838 static int talk_to_netback(struct xenbus_device
*dev
,
1839 struct netfront_info
*info
)
1841 const char *message
;
1842 struct xenbus_transaction xbt
;
1844 unsigned int feature_split_evtchn
;
1846 unsigned int max_queues
= 0;
1847 struct netfront_queue
*queue
= NULL
;
1848 unsigned int num_queues
= 1;
1850 info
->netdev
->irq
= 0;
1852 /* Check if backend supports multiple queues */
1853 err
= xenbus_scanf(XBT_NIL
, info
->xbdev
->otherend
,
1854 "multi-queue-max-queues", "%u", &max_queues
);
1857 num_queues
= min(max_queues
, xennet_max_queues
);
1859 /* Check feature-split-event-channels */
1860 err
= xenbus_scanf(XBT_NIL
, info
->xbdev
->otherend
,
1861 "feature-split-event-channels", "%u",
1862 &feature_split_evtchn
);
1864 feature_split_evtchn
= 0;
1866 /* Read mac addr. */
1867 err
= xen_net_read_mac(dev
, info
->netdev
->dev_addr
);
1869 xenbus_dev_fatal(dev
, err
, "parsing %s/mac", dev
->nodename
);
1874 xennet_destroy_queues(info
);
1876 err
= xennet_create_queues(info
, num_queues
);
1880 /* Create shared ring, alloc event channel -- for each queue */
1881 for (i
= 0; i
< num_queues
; ++i
) {
1882 queue
= &info
->queues
[i
];
1883 err
= setup_netfront(dev
, queue
, feature_split_evtchn
);
1885 /* setup_netfront() will tidy up the current
1886 * queue on error, but we need to clean up
1887 * those already allocated.
1891 netif_set_real_num_tx_queues(info
->netdev
, i
);
1901 err
= xenbus_transaction_start(&xbt
);
1903 xenbus_dev_fatal(dev
, err
, "starting transaction");
1907 if (num_queues
== 1) {
1908 err
= write_queue_xenstore_keys(&info
->queues
[0], &xbt
, 0); /* flat */
1910 goto abort_transaction_no_dev_fatal
;
1912 /* Write the number of queues */
1913 err
= xenbus_printf(xbt
, dev
->nodename
, "multi-queue-num-queues",
1916 message
= "writing multi-queue-num-queues";
1917 goto abort_transaction_no_dev_fatal
;
1920 /* Write the keys for each queue */
1921 for (i
= 0; i
< num_queues
; ++i
) {
1922 queue
= &info
->queues
[i
];
1923 err
= write_queue_xenstore_keys(queue
, &xbt
, 1); /* hierarchical */
1925 goto abort_transaction_no_dev_fatal
;
1929 /* The remaining keys are not queue-specific */
1930 err
= xenbus_printf(xbt
, dev
->nodename
, "request-rx-copy", "%u",
1933 message
= "writing request-rx-copy";
1934 goto abort_transaction
;
1937 err
= xenbus_printf(xbt
, dev
->nodename
, "feature-rx-notify", "%d", 1);
1939 message
= "writing feature-rx-notify";
1940 goto abort_transaction
;
1943 err
= xenbus_printf(xbt
, dev
->nodename
, "feature-sg", "%d", 1);
1945 message
= "writing feature-sg";
1946 goto abort_transaction
;
1949 err
= xenbus_printf(xbt
, dev
->nodename
, "feature-gso-tcpv4", "%d", 1);
1951 message
= "writing feature-gso-tcpv4";
1952 goto abort_transaction
;
1955 err
= xenbus_write(xbt
, dev
->nodename
, "feature-gso-tcpv6", "1");
1957 message
= "writing feature-gso-tcpv6";
1958 goto abort_transaction
;
1961 err
= xenbus_write(xbt
, dev
->nodename
, "feature-ipv6-csum-offload",
1964 message
= "writing feature-ipv6-csum-offload";
1965 goto abort_transaction
;
1968 err
= xenbus_transaction_end(xbt
, 0);
1972 xenbus_dev_fatal(dev
, err
, "completing transaction");
1979 xenbus_dev_fatal(dev
, err
, "%s", message
);
1980 abort_transaction_no_dev_fatal
:
1981 xenbus_transaction_end(xbt
, 1);
1983 xennet_disconnect_backend(info
);
1984 kfree(info
->queues
);
1985 info
->queues
= NULL
;
1987 netif_set_real_num_tx_queues(info
->netdev
, 0);
1993 static int xennet_connect(struct net_device
*dev
)
1995 struct netfront_info
*np
= netdev_priv(dev
);
1996 unsigned int num_queues
= 0;
1998 unsigned int feature_rx_copy
;
2000 struct netfront_queue
*queue
= NULL
;
2002 err
= xenbus_scanf(XBT_NIL
, np
->xbdev
->otherend
,
2003 "feature-rx-copy", "%u", &feature_rx_copy
);
2005 feature_rx_copy
= 0;
2007 if (!feature_rx_copy
) {
2009 "backend does not support copying receive path\n");
2013 err
= talk_to_netback(np
->xbdev
, np
);
2017 /* talk_to_netback() sets the correct number of queues */
2018 num_queues
= dev
->real_num_tx_queues
;
2021 netdev_update_features(dev
);
2025 * All public and private state should now be sane. Get
2026 * ready to start sending and receiving packets and give the driver
2027 * domain a kick because we've probably just requeued some
2030 netif_carrier_on(np
->netdev
);
2031 for (j
= 0; j
< num_queues
; ++j
) {
2032 queue
= &np
->queues
[j
];
2034 notify_remote_via_irq(queue
->tx_irq
);
2035 if (queue
->tx_irq
!= queue
->rx_irq
)
2036 notify_remote_via_irq(queue
->rx_irq
);
2038 spin_lock_irq(&queue
->tx_lock
);
2039 xennet_tx_buf_gc(queue
);
2040 spin_unlock_irq(&queue
->tx_lock
);
2042 spin_lock_bh(&queue
->rx_lock
);
2043 xennet_alloc_rx_buffers(queue
);
2044 spin_unlock_bh(&queue
->rx_lock
);
2051 * Callback received when the backend's state changes.
2053 static void netback_changed(struct xenbus_device
*dev
,
2054 enum xenbus_state backend_state
)
2056 struct netfront_info
*np
= dev_get_drvdata(&dev
->dev
);
2057 struct net_device
*netdev
= np
->netdev
;
2059 dev_dbg(&dev
->dev
, "%s\n", xenbus_strstate(backend_state
));
2061 switch (backend_state
) {
2062 case XenbusStateInitialising
:
2063 case XenbusStateInitialised
:
2064 case XenbusStateReconfiguring
:
2065 case XenbusStateReconfigured
:
2066 case XenbusStateUnknown
:
2069 case XenbusStateInitWait
:
2070 if (dev
->state
!= XenbusStateInitialising
)
2072 if (xennet_connect(netdev
) != 0)
2074 xenbus_switch_state(dev
, XenbusStateConnected
);
2077 case XenbusStateConnected
:
2078 netdev_notify_peers(netdev
);
2081 case XenbusStateClosed
:
2082 if (dev
->state
== XenbusStateClosed
)
2084 /* Missed the backend's CLOSING state -- fallthrough */
2085 case XenbusStateClosing
:
2086 xenbus_frontend_closed(dev
);
2091 static const struct xennet_stat
{
2092 char name
[ETH_GSTRING_LEN
];
2094 } xennet_stats
[] = {
2096 "rx_gso_checksum_fixup",
2097 offsetof(struct netfront_info
, rx_gso_checksum_fixup
)
2101 static int xennet_get_sset_count(struct net_device
*dev
, int string_set
)
2103 switch (string_set
) {
2105 return ARRAY_SIZE(xennet_stats
);
2111 static void xennet_get_ethtool_stats(struct net_device
*dev
,
2112 struct ethtool_stats
*stats
, u64
* data
)
2114 void *np
= netdev_priv(dev
);
2117 for (i
= 0; i
< ARRAY_SIZE(xennet_stats
); i
++)
2118 data
[i
] = atomic_read((atomic_t
*)(np
+ xennet_stats
[i
].offset
));
2121 static void xennet_get_strings(struct net_device
*dev
, u32 stringset
, u8
* data
)
2125 switch (stringset
) {
2127 for (i
= 0; i
< ARRAY_SIZE(xennet_stats
); i
++)
2128 memcpy(data
+ i
* ETH_GSTRING_LEN
,
2129 xennet_stats
[i
].name
, ETH_GSTRING_LEN
);
2134 static const struct ethtool_ops xennet_ethtool_ops
=
2136 .get_link
= ethtool_op_get_link
,
2138 .get_sset_count
= xennet_get_sset_count
,
2139 .get_ethtool_stats
= xennet_get_ethtool_stats
,
2140 .get_strings
= xennet_get_strings
,
2144 static ssize_t
show_rxbuf_min(struct device
*dev
,
2145 struct device_attribute
*attr
, char *buf
)
2147 struct net_device
*netdev
= to_net_dev(dev
);
2148 struct netfront_info
*info
= netdev_priv(netdev
);
2149 unsigned int num_queues
= netdev
->real_num_tx_queues
;
2152 return sprintf(buf
, "%u\n", info
->queues
[0].rx_min_target
);
2154 return sprintf(buf
, "%u\n", RX_MIN_TARGET
);
2157 static ssize_t
store_rxbuf_min(struct device
*dev
,
2158 struct device_attribute
*attr
,
2159 const char *buf
, size_t len
)
2161 struct net_device
*netdev
= to_net_dev(dev
);
2162 struct netfront_info
*np
= netdev_priv(netdev
);
2163 unsigned int num_queues
= netdev
->real_num_tx_queues
;
2165 unsigned long target
;
2167 struct netfront_queue
*queue
;
2169 if (!capable(CAP_NET_ADMIN
))
2172 target
= simple_strtoul(buf
, &endp
, 0);
2176 if (target
< RX_MIN_TARGET
)
2177 target
= RX_MIN_TARGET
;
2178 if (target
> RX_MAX_TARGET
)
2179 target
= RX_MAX_TARGET
;
2181 for (i
= 0; i
< num_queues
; ++i
) {
2182 queue
= &np
->queues
[i
];
2183 spin_lock_bh(&queue
->rx_lock
);
2184 if (target
> queue
->rx_max_target
)
2185 queue
->rx_max_target
= target
;
2186 queue
->rx_min_target
= target
;
2187 if (target
> queue
->rx_target
)
2188 queue
->rx_target
= target
;
2190 xennet_alloc_rx_buffers(queue
);
2192 spin_unlock_bh(&queue
->rx_lock
);
2197 static ssize_t
show_rxbuf_max(struct device
*dev
,
2198 struct device_attribute
*attr
, char *buf
)
2200 struct net_device
*netdev
= to_net_dev(dev
);
2201 struct netfront_info
*info
= netdev_priv(netdev
);
2202 unsigned int num_queues
= netdev
->real_num_tx_queues
;
2205 return sprintf(buf
, "%u\n", info
->queues
[0].rx_max_target
);
2207 return sprintf(buf
, "%u\n", RX_MAX_TARGET
);
2210 static ssize_t
store_rxbuf_max(struct device
*dev
,
2211 struct device_attribute
*attr
,
2212 const char *buf
, size_t len
)
2214 struct net_device
*netdev
= to_net_dev(dev
);
2215 struct netfront_info
*np
= netdev_priv(netdev
);
2216 unsigned int num_queues
= netdev
->real_num_tx_queues
;
2218 unsigned long target
;
2220 struct netfront_queue
*queue
= NULL
;
2222 if (!capable(CAP_NET_ADMIN
))
2225 target
= simple_strtoul(buf
, &endp
, 0);
2229 if (target
< RX_MIN_TARGET
)
2230 target
= RX_MIN_TARGET
;
2231 if (target
> RX_MAX_TARGET
)
2232 target
= RX_MAX_TARGET
;
2234 for (i
= 0; i
< num_queues
; ++i
) {
2235 queue
= &np
->queues
[i
];
2236 spin_lock_bh(&queue
->rx_lock
);
2237 if (target
< queue
->rx_min_target
)
2238 queue
->rx_min_target
= target
;
2239 queue
->rx_max_target
= target
;
2240 if (target
< queue
->rx_target
)
2241 queue
->rx_target
= target
;
2243 xennet_alloc_rx_buffers(queue
);
2245 spin_unlock_bh(&queue
->rx_lock
);
2250 static ssize_t
show_rxbuf_cur(struct device
*dev
,
2251 struct device_attribute
*attr
, char *buf
)
2253 struct net_device
*netdev
= to_net_dev(dev
);
2254 struct netfront_info
*info
= netdev_priv(netdev
);
2255 unsigned int num_queues
= netdev
->real_num_tx_queues
;
2258 return sprintf(buf
, "%u\n", info
->queues
[0].rx_target
);
2260 return sprintf(buf
, "0\n");
2263 static struct device_attribute xennet_attrs
[] = {
2264 __ATTR(rxbuf_min
, S_IRUGO
|S_IWUSR
, show_rxbuf_min
, store_rxbuf_min
),
2265 __ATTR(rxbuf_max
, S_IRUGO
|S_IWUSR
, show_rxbuf_max
, store_rxbuf_max
),
2266 __ATTR(rxbuf_cur
, S_IRUGO
, show_rxbuf_cur
, NULL
),
2269 static int xennet_sysfs_addif(struct net_device
*netdev
)
2274 for (i
= 0; i
< ARRAY_SIZE(xennet_attrs
); i
++) {
2275 err
= device_create_file(&netdev
->dev
,
2284 device_remove_file(&netdev
->dev
, &xennet_attrs
[i
]);
2288 static void xennet_sysfs_delif(struct net_device
*netdev
)
2292 for (i
= 0; i
< ARRAY_SIZE(xennet_attrs
); i
++)
2293 device_remove_file(&netdev
->dev
, &xennet_attrs
[i
]);
2296 #endif /* CONFIG_SYSFS */
2298 static int xennet_remove(struct xenbus_device
*dev
)
2300 struct netfront_info
*info
= dev_get_drvdata(&dev
->dev
);
2301 unsigned int num_queues
= info
->netdev
->real_num_tx_queues
;
2302 struct netfront_queue
*queue
= NULL
;
2305 dev_dbg(&dev
->dev
, "%s\n", dev
->nodename
);
2307 xennet_disconnect_backend(info
);
2309 xennet_sysfs_delif(info
->netdev
);
2311 unregister_netdev(info
->netdev
);
2313 for (i
= 0; i
< num_queues
; ++i
) {
2314 queue
= &info
->queues
[i
];
2315 del_timer_sync(&queue
->rx_refill_timer
);
2319 kfree(info
->queues
);
2320 info
->queues
= NULL
;
2323 free_percpu(info
->stats
);
2325 free_netdev(info
->netdev
);
2330 static const struct xenbus_device_id netfront_ids
[] = {
2335 static struct xenbus_driver netfront_driver
= {
2336 .ids
= netfront_ids
,
2337 .probe
= netfront_probe
,
2338 .remove
= xennet_remove
,
2339 .resume
= netfront_resume
,
2340 .otherend_changed
= netback_changed
,
2343 static int __init
netif_init(void)
2348 if (!xen_has_pv_nic_devices())
2351 pr_info("Initialising Xen virtual ethernet driver\n");
2353 /* Allow as many queues as there are CPUs, by default */
2354 xennet_max_queues
= num_online_cpus();
2356 return xenbus_register_frontend(&netfront_driver
);
2358 module_init(netif_init
);
2361 static void __exit
netif_exit(void)
2363 xenbus_unregister_driver(&netfront_driver
);
2365 module_exit(netif_exit
);
2367 MODULE_DESCRIPTION("Xen virtual network device frontend");
2368 MODULE_LICENSE("GPL");
2369 MODULE_ALIAS("xen:vif");
2370 MODULE_ALIAS("xennet");