root / hw / xen_nic.c @ 0ef654e3
History | View | Annotate | Download (13.9 kB)
1 |
/*
|
---|---|
2 |
* xen paravirt network card backend
|
3 |
*
|
4 |
* (c) Gerd Hoffmann <kraxel@redhat.com>
|
5 |
*
|
6 |
* This program is free software; you can redistribute it and/or modify
|
7 |
* it under the terms of the GNU General Public License as published by
|
8 |
* the Free Software Foundation; under version 2 of the License.
|
9 |
*
|
10 |
* This program is distributed in the hope that it will be useful,
|
11 |
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
12 |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
13 |
* GNU General Public License for more details.
|
14 |
*
|
15 |
* You should have received a copy of the GNU General Public License along
|
16 |
* with this program; if not, see <http://www.gnu.org/licenses/>.
|
17 |
*
|
18 |
* Contributions after 2012-01-13 are licensed under the terms of the
|
19 |
* GNU GPL, version 2 or (at your option) any later version.
|
20 |
*/
|
21 |
|
22 |
#include <stdio.h> |
23 |
#include <stdlib.h> |
24 |
#include <stdarg.h> |
25 |
#include <string.h> |
26 |
#include <unistd.h> |
27 |
#include <signal.h> |
28 |
#include <inttypes.h> |
29 |
#include <fcntl.h> |
30 |
#include <errno.h> |
31 |
#include <sys/socket.h> |
32 |
#include <sys/ioctl.h> |
33 |
#include <sys/types.h> |
34 |
#include <sys/stat.h> |
35 |
#include <sys/mman.h> |
36 |
#include <sys/wait.h> |
37 |
|
38 |
#include <xs.h> |
39 |
#include <xenctrl.h> |
40 |
#include <xen/io/xenbus.h> |
41 |
#include <xen/io/netif.h> |
42 |
|
43 |
#include "hw.h" |
44 |
#include "net.h" |
45 |
#include "net/checksum.h" |
46 |
#include "net/util.h" |
47 |
#include "qemu-char.h" |
48 |
#include "xen_backend.h" |
49 |
|
50 |
/* ------------------------------------------------------------- */
|
51 |
|
52 |
struct XenNetDev {
|
53 |
struct XenDevice xendev; /* must be first */ |
54 |
char *mac;
|
55 |
int tx_work;
|
56 |
int tx_ring_ref;
|
57 |
int rx_ring_ref;
|
58 |
struct netif_tx_sring *txs;
|
59 |
struct netif_rx_sring *rxs;
|
60 |
netif_tx_back_ring_t tx_ring; |
61 |
netif_rx_back_ring_t rx_ring; |
62 |
NICConf conf; |
63 |
NICState *nic; |
64 |
}; |
65 |
|
66 |
/* ------------------------------------------------------------- */
|
67 |
|
68 |
static void net_tx_response(struct XenNetDev *netdev, netif_tx_request_t *txp, int8_t st) |
69 |
{ |
70 |
RING_IDX i = netdev->tx_ring.rsp_prod_pvt; |
71 |
netif_tx_response_t *resp; |
72 |
int notify;
|
73 |
|
74 |
resp = RING_GET_RESPONSE(&netdev->tx_ring, i); |
75 |
resp->id = txp->id; |
76 |
resp->status = st; |
77 |
|
78 |
#if 0
|
79 |
if (txp->flags & NETTXF_extra_info) {
|
80 |
RING_GET_RESPONSE(&netdev->tx_ring, ++i)->status = NETIF_RSP_NULL;
|
81 |
}
|
82 |
#endif
|
83 |
|
84 |
netdev->tx_ring.rsp_prod_pvt = ++i; |
85 |
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netdev->tx_ring, notify); |
86 |
if (notify) {
|
87 |
xen_be_send_notify(&netdev->xendev); |
88 |
} |
89 |
|
90 |
if (i == netdev->tx_ring.req_cons) {
|
91 |
int more_to_do;
|
92 |
RING_FINAL_CHECK_FOR_REQUESTS(&netdev->tx_ring, more_to_do); |
93 |
if (more_to_do) {
|
94 |
netdev->tx_work++; |
95 |
} |
96 |
} |
97 |
} |
98 |
|
99 |
static void net_tx_error(struct XenNetDev *netdev, netif_tx_request_t *txp, RING_IDX end) |
100 |
{ |
101 |
#if 0
|
102 |
/*
|
103 |
* Hmm, why netback fails everything in the ring?
|
104 |
* Should we do that even when not supporting SG and TSO?
|
105 |
*/
|
106 |
RING_IDX cons = netdev->tx_ring.req_cons;
|
107 |
|
108 |
do {
|
109 |
make_tx_response(netif, txp, NETIF_RSP_ERROR);
|
110 |
if (cons >= end) {
|
111 |
break;
|
112 |
}
|
113 |
txp = RING_GET_REQUEST(&netdev->tx_ring, cons++);
|
114 |
} while (1);
|
115 |
netdev->tx_ring.req_cons = cons;
|
116 |
netif_schedule_work(netif);
|
117 |
netif_put(netif);
|
118 |
#else
|
119 |
net_tx_response(netdev, txp, NETIF_RSP_ERROR); |
120 |
#endif
|
121 |
} |
122 |
|
123 |
static void net_tx_packets(struct XenNetDev *netdev) |
124 |
{ |
125 |
netif_tx_request_t txreq; |
126 |
RING_IDX rc, rp; |
127 |
void *page;
|
128 |
void *tmpbuf = NULL; |
129 |
|
130 |
for (;;) {
|
131 |
rc = netdev->tx_ring.req_cons; |
132 |
rp = netdev->tx_ring.sring->req_prod; |
133 |
xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
|
134 |
|
135 |
while ((rc != rp)) {
|
136 |
if (RING_REQUEST_CONS_OVERFLOW(&netdev->tx_ring, rc)) {
|
137 |
break;
|
138 |
} |
139 |
memcpy(&txreq, RING_GET_REQUEST(&netdev->tx_ring, rc), sizeof(txreq));
|
140 |
netdev->tx_ring.req_cons = ++rc; |
141 |
|
142 |
#if 1 |
143 |
/* should not happen in theory, we don't announce the *
|
144 |
* feature-{sg,gso,whatelse} flags in xenstore (yet?) */
|
145 |
if (txreq.flags & NETTXF_extra_info) {
|
146 |
xen_be_printf(&netdev->xendev, 0, "FIXME: extra info flag\n"); |
147 |
net_tx_error(netdev, &txreq, rc); |
148 |
continue;
|
149 |
} |
150 |
if (txreq.flags & NETTXF_more_data) {
|
151 |
xen_be_printf(&netdev->xendev, 0, "FIXME: more data flag\n"); |
152 |
net_tx_error(netdev, &txreq, rc); |
153 |
continue;
|
154 |
} |
155 |
#endif
|
156 |
|
157 |
if (txreq.size < 14) { |
158 |
xen_be_printf(&netdev->xendev, 0, "bad packet size: %d\n", txreq.size); |
159 |
net_tx_error(netdev, &txreq, rc); |
160 |
continue;
|
161 |
} |
162 |
|
163 |
if ((txreq.offset + txreq.size) > XC_PAGE_SIZE) {
|
164 |
xen_be_printf(&netdev->xendev, 0, "error: page crossing\n"); |
165 |
net_tx_error(netdev, &txreq, rc); |
166 |
continue;
|
167 |
} |
168 |
|
169 |
xen_be_printf(&netdev->xendev, 3, "tx packet ref %d, off %d, len %d, flags 0x%x%s%s%s%s\n", |
170 |
txreq.gref, txreq.offset, txreq.size, txreq.flags, |
171 |
(txreq.flags & NETTXF_csum_blank) ? " csum_blank" : "", |
172 |
(txreq.flags & NETTXF_data_validated) ? " data_validated" : "", |
173 |
(txreq.flags & NETTXF_more_data) ? " more_data" : "", |
174 |
(txreq.flags & NETTXF_extra_info) ? " extra_info" : ""); |
175 |
|
176 |
page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev, |
177 |
netdev->xendev.dom, |
178 |
txreq.gref, PROT_READ); |
179 |
if (page == NULL) { |
180 |
xen_be_printf(&netdev->xendev, 0, "error: tx gref dereference failed (%d)\n", |
181 |
txreq.gref); |
182 |
net_tx_error(netdev, &txreq, rc); |
183 |
continue;
|
184 |
} |
185 |
if (txreq.flags & NETTXF_csum_blank) {
|
186 |
/* have read-only mapping -> can't fill checksum in-place */
|
187 |
if (!tmpbuf) {
|
188 |
tmpbuf = g_malloc(XC_PAGE_SIZE); |
189 |
} |
190 |
memcpy(tmpbuf, page + txreq.offset, txreq.size); |
191 |
net_checksum_calculate(tmpbuf, txreq.size); |
192 |
qemu_send_packet(&netdev->nic->nc, tmpbuf, txreq.size); |
193 |
} else {
|
194 |
qemu_send_packet(&netdev->nic->nc, page + txreq.offset, txreq.size); |
195 |
} |
196 |
xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
|
197 |
net_tx_response(netdev, &txreq, NETIF_RSP_OKAY); |
198 |
} |
199 |
if (!netdev->tx_work) {
|
200 |
break;
|
201 |
} |
202 |
netdev->tx_work = 0;
|
203 |
} |
204 |
g_free(tmpbuf); |
205 |
} |
206 |
|
207 |
/* ------------------------------------------------------------- */
|
208 |
|
209 |
static void net_rx_response(struct XenNetDev *netdev, |
210 |
netif_rx_request_t *req, int8_t st, |
211 |
uint16_t offset, uint16_t size, |
212 |
uint16_t flags) |
213 |
{ |
214 |
RING_IDX i = netdev->rx_ring.rsp_prod_pvt; |
215 |
netif_rx_response_t *resp; |
216 |
int notify;
|
217 |
|
218 |
resp = RING_GET_RESPONSE(&netdev->rx_ring, i); |
219 |
resp->offset = offset; |
220 |
resp->flags = flags; |
221 |
resp->id = req->id; |
222 |
resp->status = (int16_t)size; |
223 |
if (st < 0) { |
224 |
resp->status = (int16_t)st; |
225 |
} |
226 |
|
227 |
xen_be_printf(&netdev->xendev, 3, "rx response: idx %d, status %d, flags 0x%x\n", |
228 |
i, resp->status, resp->flags); |
229 |
|
230 |
netdev->rx_ring.rsp_prod_pvt = ++i; |
231 |
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netdev->rx_ring, notify); |
232 |
if (notify) {
|
233 |
xen_be_send_notify(&netdev->xendev); |
234 |
} |
235 |
} |
236 |
|
237 |
#define NET_IP_ALIGN 2 |
238 |
|
239 |
static int net_rx_ok(VLANClientState *nc) |
240 |
{ |
241 |
struct XenNetDev *netdev = DO_UPCAST(NICState, nc, nc)->opaque;
|
242 |
RING_IDX rc, rp; |
243 |
|
244 |
if (netdev->xendev.be_state != XenbusStateConnected) {
|
245 |
return 0; |
246 |
} |
247 |
|
248 |
rc = netdev->rx_ring.req_cons; |
249 |
rp = netdev->rx_ring.sring->req_prod; |
250 |
xen_rmb(); |
251 |
|
252 |
if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) {
|
253 |
xen_be_printf(&netdev->xendev, 2, "%s: no rx buffers (%d/%d)\n", |
254 |
__FUNCTION__, rc, rp); |
255 |
return 0; |
256 |
} |
257 |
return 1; |
258 |
} |
259 |
|
260 |
static ssize_t net_rx_packet(VLANClientState *nc, const uint8_t *buf, size_t size) |
261 |
{ |
262 |
struct XenNetDev *netdev = DO_UPCAST(NICState, nc, nc)->opaque;
|
263 |
netif_rx_request_t rxreq; |
264 |
RING_IDX rc, rp; |
265 |
void *page;
|
266 |
|
267 |
if (netdev->xendev.be_state != XenbusStateConnected) {
|
268 |
return -1; |
269 |
} |
270 |
|
271 |
rc = netdev->rx_ring.req_cons; |
272 |
rp = netdev->rx_ring.sring->req_prod; |
273 |
xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
|
274 |
|
275 |
if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) {
|
276 |
xen_be_printf(&netdev->xendev, 2, "no buffer, drop packet\n"); |
277 |
return -1; |
278 |
} |
279 |
if (size > XC_PAGE_SIZE - NET_IP_ALIGN) {
|
280 |
xen_be_printf(&netdev->xendev, 0, "packet too big (%lu > %ld)", |
281 |
(unsigned long)size, XC_PAGE_SIZE - NET_IP_ALIGN); |
282 |
return -1; |
283 |
} |
284 |
|
285 |
memcpy(&rxreq, RING_GET_REQUEST(&netdev->rx_ring, rc), sizeof(rxreq));
|
286 |
netdev->rx_ring.req_cons = ++rc; |
287 |
|
288 |
page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev, |
289 |
netdev->xendev.dom, |
290 |
rxreq.gref, PROT_WRITE); |
291 |
if (page == NULL) { |
292 |
xen_be_printf(&netdev->xendev, 0, "error: rx gref dereference failed (%d)\n", |
293 |
rxreq.gref); |
294 |
net_rx_response(netdev, &rxreq, NETIF_RSP_ERROR, 0, 0, 0); |
295 |
return -1; |
296 |
} |
297 |
memcpy(page + NET_IP_ALIGN, buf, size); |
298 |
xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
|
299 |
net_rx_response(netdev, &rxreq, NETIF_RSP_OKAY, NET_IP_ALIGN, size, 0);
|
300 |
|
301 |
return size;
|
302 |
} |
303 |
|
304 |
/* ------------------------------------------------------------- */
|
305 |
|
306 |
static NetClientInfo net_xen_info = {
|
307 |
.type = NET_CLIENT_TYPE_NIC, |
308 |
.size = sizeof(NICState),
|
309 |
.can_receive = net_rx_ok, |
310 |
.receive = net_rx_packet, |
311 |
}; |
312 |
|
313 |
static int net_init(struct XenDevice *xendev) |
314 |
{ |
315 |
struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
316 |
|
317 |
/* read xenstore entries */
|
318 |
if (netdev->mac == NULL) { |
319 |
netdev->mac = xenstore_read_be_str(&netdev->xendev, "mac");
|
320 |
} |
321 |
|
322 |
/* do we have all we need? */
|
323 |
if (netdev->mac == NULL) { |
324 |
return -1; |
325 |
} |
326 |
|
327 |
if (net_parse_macaddr(netdev->conf.macaddr.a, netdev->mac) < 0) { |
328 |
return -1; |
329 |
} |
330 |
|
331 |
netdev->conf.vlan = qemu_find_vlan(netdev->xendev.dev, 1);
|
332 |
netdev->conf.peer = NULL;
|
333 |
|
334 |
netdev->nic = qemu_new_nic(&net_xen_info, &netdev->conf, |
335 |
"xen", NULL, netdev); |
336 |
|
337 |
snprintf(netdev->nic->nc.info_str, sizeof(netdev->nic->nc.info_str),
|
338 |
"nic: xenbus vif macaddr=%s", netdev->mac);
|
339 |
|
340 |
/* fill info */
|
341 |
xenstore_write_be_int(&netdev->xendev, "feature-rx-copy", 1); |
342 |
xenstore_write_be_int(&netdev->xendev, "feature-rx-flip", 0); |
343 |
|
344 |
return 0; |
345 |
} |
346 |
|
347 |
static int net_connect(struct XenDevice *xendev) |
348 |
{ |
349 |
struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
350 |
int rx_copy;
|
351 |
|
352 |
if (xenstore_read_fe_int(&netdev->xendev, "tx-ring-ref", |
353 |
&netdev->tx_ring_ref) == -1) {
|
354 |
return -1; |
355 |
} |
356 |
if (xenstore_read_fe_int(&netdev->xendev, "rx-ring-ref", |
357 |
&netdev->rx_ring_ref) == -1) {
|
358 |
return 1; |
359 |
} |
360 |
if (xenstore_read_fe_int(&netdev->xendev, "event-channel", |
361 |
&netdev->xendev.remote_port) == -1) {
|
362 |
return -1; |
363 |
} |
364 |
|
365 |
if (xenstore_read_fe_int(&netdev->xendev, "request-rx-copy", &rx_copy) == -1) { |
366 |
rx_copy = 0;
|
367 |
} |
368 |
if (rx_copy == 0) { |
369 |
xen_be_printf(&netdev->xendev, 0, "frontend doesn't support rx-copy.\n"); |
370 |
return -1; |
371 |
} |
372 |
|
373 |
netdev->txs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev, |
374 |
netdev->xendev.dom, |
375 |
netdev->tx_ring_ref, |
376 |
PROT_READ | PROT_WRITE); |
377 |
netdev->rxs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev, |
378 |
netdev->xendev.dom, |
379 |
netdev->rx_ring_ref, |
380 |
PROT_READ | PROT_WRITE); |
381 |
if (!netdev->txs || !netdev->rxs) {
|
382 |
return -1; |
383 |
} |
384 |
BACK_RING_INIT(&netdev->tx_ring, netdev->txs, XC_PAGE_SIZE); |
385 |
BACK_RING_INIT(&netdev->rx_ring, netdev->rxs, XC_PAGE_SIZE); |
386 |
|
387 |
xen_be_bind_evtchn(&netdev->xendev); |
388 |
|
389 |
xen_be_printf(&netdev->xendev, 1, "ok: tx-ring-ref %d, rx-ring-ref %d, " |
390 |
"remote port %d, local port %d\n",
|
391 |
netdev->tx_ring_ref, netdev->rx_ring_ref, |
392 |
netdev->xendev.remote_port, netdev->xendev.local_port); |
393 |
|
394 |
net_tx_packets(netdev); |
395 |
return 0; |
396 |
} |
397 |
|
398 |
static void net_disconnect(struct XenDevice *xendev) |
399 |
{ |
400 |
struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
401 |
|
402 |
xen_be_unbind_evtchn(&netdev->xendev); |
403 |
|
404 |
if (netdev->txs) {
|
405 |
xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
|
406 |
netdev->txs = NULL;
|
407 |
} |
408 |
if (netdev->rxs) {
|
409 |
xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
|
410 |
netdev->rxs = NULL;
|
411 |
} |
412 |
if (netdev->nic) {
|
413 |
qemu_del_vlan_client(&netdev->nic->nc); |
414 |
netdev->nic = NULL;
|
415 |
} |
416 |
} |
417 |
|
418 |
static void net_event(struct XenDevice *xendev) |
419 |
{ |
420 |
struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
421 |
net_tx_packets(netdev); |
422 |
} |
423 |
|
424 |
static int net_free(struct XenDevice *xendev) |
425 |
{ |
426 |
struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
427 |
|
428 |
g_free(netdev->mac); |
429 |
return 0; |
430 |
} |
431 |
|
432 |
/* ------------------------------------------------------------- */
|
433 |
|
434 |
struct XenDevOps xen_netdev_ops = {
|
435 |
.size = sizeof(struct XenNetDev), |
436 |
.flags = DEVOPS_FLAG_NEED_GNTDEV, |
437 |
.init = net_init, |
438 |
.initialise = net_connect, |
439 |
.event = net_event, |
440 |
.disconnect = net_disconnect, |
441 |
.free = net_free, |
442 |
}; |