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char: move ringbuf/memory to its own file
[qemu/ar7.git] / hw / net / xen_nic.c
blob20c43a61b3383bc957c650dcf2f18c4bfd14b7c7
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 "qemu/osdep.h"
23 #include <sys/socket.h>
24 #include <sys/ioctl.h>
25 #include <sys/wait.h>
26
27 #include "hw/hw.h"
28 #include "net/net.h"
29 #include "net/checksum.h"
30 #include "net/util.h"
31 #include "hw/xen/xen_backend.h"
32
33 #include <xen/io/netif.h>
34
35 /* ------------------------------------------------------------- */
36
37 struct XenNetDev {
38 struct XenDevice xendev; /* must be first */
39 char *mac;
40 int tx_work;
41 int tx_ring_ref;
42 int rx_ring_ref;
43 struct netif_tx_sring *txs;
44 struct netif_rx_sring *rxs;
45 netif_tx_back_ring_t tx_ring;
46 netif_rx_back_ring_t rx_ring;
47 NICConf conf;
48 NICState *nic;
49 };
50
51 /* ------------------------------------------------------------- */
52
53 static void net_tx_response(struct XenNetDev *netdev, netif_tx_request_t *txp, int8_t st)
54 {
55 RING_IDX i = netdev->tx_ring.rsp_prod_pvt;
56 netif_tx_response_t *resp;
57 int notify;
58
59 resp = RING_GET_RESPONSE(&netdev->tx_ring, i);
60 resp->id = txp->id;
61 resp->status = st;
62
63 #if 0
64 if (txp->flags & NETTXF_extra_info) {
65 RING_GET_RESPONSE(&netdev->tx_ring, ++i)->status = NETIF_RSP_NULL;
66 }
67 #endif
68
69 netdev->tx_ring.rsp_prod_pvt = ++i;
70 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netdev->tx_ring, notify);
71 if (notify) {
72 xen_pv_send_notify(&netdev->xendev);
73 }
74
75 if (i == netdev->tx_ring.req_cons) {
76 int more_to_do;
77 RING_FINAL_CHECK_FOR_REQUESTS(&netdev->tx_ring, more_to_do);
78 if (more_to_do) {
79 netdev->tx_work++;
80 }
81 }
82 }
83
84 static void net_tx_error(struct XenNetDev *netdev, netif_tx_request_t *txp, RING_IDX end)
85 {
86 #if 0
87 /*
88 * Hmm, why netback fails everything in the ring?
89 * Should we do that even when not supporting SG and TSO?
90 */
91 RING_IDX cons = netdev->tx_ring.req_cons;
92
93 do {
94 make_tx_response(netif, txp, NETIF_RSP_ERROR);
95 if (cons >= end) {
96 break;
97 }
98 txp = RING_GET_REQUEST(&netdev->tx_ring, cons++);
99 } while (1);
100 netdev->tx_ring.req_cons = cons;
101 netif_schedule_work(netif);
102 netif_put(netif);
103 #else
104 net_tx_response(netdev, txp, NETIF_RSP_ERROR);
105 #endif
106 }
107
108 static void net_tx_packets(struct XenNetDev *netdev)
109 {
110 netif_tx_request_t txreq;
111 RING_IDX rc, rp;
112 void *page;
113 void *tmpbuf = NULL;
114
115 for (;;) {
116 rc = netdev->tx_ring.req_cons;
117 rp = netdev->tx_ring.sring->req_prod;
118 xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
119
120 while ((rc != rp)) {
121 if (RING_REQUEST_CONS_OVERFLOW(&netdev->tx_ring, rc)) {
122 break;
123 }
124 memcpy(&txreq, RING_GET_REQUEST(&netdev->tx_ring, rc), sizeof(txreq));
125 netdev->tx_ring.req_cons = ++rc;
126
127 #if 1
128 /* should not happen in theory, we don't announce the *
129 * feature-{sg,gso,whatelse} flags in xenstore (yet?) */
130 if (txreq.flags & NETTXF_extra_info) {
131 xen_pv_printf(&netdev->xendev, 0, "FIXME: extra info flag\n");
132 net_tx_error(netdev, &txreq, rc);
133 continue;
134 }
135 if (txreq.flags & NETTXF_more_data) {
136 xen_pv_printf(&netdev->xendev, 0, "FIXME: more data flag\n");
137 net_tx_error(netdev, &txreq, rc);
138 continue;
139 }
140 #endif
141
142 if (txreq.size < 14) {
143 xen_pv_printf(&netdev->xendev, 0, "bad packet size: %d\n",
144 txreq.size);
145 net_tx_error(netdev, &txreq, rc);
146 continue;
147 }
148
149 if ((txreq.offset + txreq.size) > XC_PAGE_SIZE) {
150 xen_pv_printf(&netdev->xendev, 0, "error: page crossing\n");
151 net_tx_error(netdev, &txreq, rc);
152 continue;
153 }
154
155 xen_pv_printf(&netdev->xendev, 3,
156 "tx packet ref %d, off %d, len %d, flags 0x%x%s%s%s%s\n",
157 txreq.gref, txreq.offset, txreq.size, txreq.flags,
158 (txreq.flags & NETTXF_csum_blank) ? " csum_blank" : "",
159 (txreq.flags & NETTXF_data_validated) ? " data_validated" : "",
160 (txreq.flags & NETTXF_more_data) ? " more_data" : "",
161 (txreq.flags & NETTXF_extra_info) ? " extra_info" : "");
162
163 page = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
164 netdev->xendev.dom,
165 txreq.gref, PROT_READ);
166 if (page == NULL) {
167 xen_pv_printf(&netdev->xendev, 0,
168 "error: tx gref dereference failed (%d)\n",
169 txreq.gref);
170 net_tx_error(netdev, &txreq, rc);
171 continue;
172 }
173 if (txreq.flags & NETTXF_csum_blank) {
174 /* have read-only mapping -> can't fill checksum in-place */
175 if (!tmpbuf) {
176 tmpbuf = g_malloc(XC_PAGE_SIZE);
177 }
178 memcpy(tmpbuf, page + txreq.offset, txreq.size);
179 net_checksum_calculate(tmpbuf, txreq.size);
180 qemu_send_packet(qemu_get_queue(netdev->nic), tmpbuf,
181 txreq.size);
182 } else {
183 qemu_send_packet(qemu_get_queue(netdev->nic),
184 page + txreq.offset, txreq.size);
185 }
186 xengnttab_unmap(netdev->xendev.gnttabdev, page, 1);
187 net_tx_response(netdev, &txreq, NETIF_RSP_OKAY);
188 }
189 if (!netdev->tx_work) {
190 break;
191 }
192 netdev->tx_work = 0;
193 }
194 g_free(tmpbuf);
195 }
196
197 /* ------------------------------------------------------------- */
198
199 static void net_rx_response(struct XenNetDev *netdev,
200 netif_rx_request_t *req, int8_t st,
201 uint16_t offset, uint16_t size,
202 uint16_t flags)
203 {
204 RING_IDX i = netdev->rx_ring.rsp_prod_pvt;
205 netif_rx_response_t *resp;
206 int notify;
207
208 resp = RING_GET_RESPONSE(&netdev->rx_ring, i);
209 resp->offset = offset;
210 resp->flags = flags;
211 resp->id = req->id;
212 resp->status = (int16_t)size;
213 if (st < 0) {
214 resp->status = (int16_t)st;
215 }
216
217 xen_pv_printf(&netdev->xendev, 3,
218 "rx response: idx %d, status %d, flags 0x%x\n",
219 i, resp->status, resp->flags);
220
221 netdev->rx_ring.rsp_prod_pvt = ++i;
222 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netdev->rx_ring, notify);
223 if (notify) {
224 xen_pv_send_notify(&netdev->xendev);
225 }
226 }
227
228 #define NET_IP_ALIGN 2
229
230 static ssize_t net_rx_packet(NetClientState *nc, const uint8_t *buf, size_t size)
231 {
232 struct XenNetDev *netdev = qemu_get_nic_opaque(nc);
233 netif_rx_request_t rxreq;
234 RING_IDX rc, rp;
235 void *page;
236
237 if (netdev->xendev.be_state != XenbusStateConnected) {
238 return -1;
239 }
240
241 rc = netdev->rx_ring.req_cons;
242 rp = netdev->rx_ring.sring->req_prod;
243 xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
244
245 if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) {
246 return 0;
247 }
248 if (size > XC_PAGE_SIZE - NET_IP_ALIGN) {
249 xen_pv_printf(&netdev->xendev, 0, "packet too big (%lu > %ld)",
250 (unsigned long)size, XC_PAGE_SIZE - NET_IP_ALIGN);
251 return -1;
252 }
253
254 memcpy(&rxreq, RING_GET_REQUEST(&netdev->rx_ring, rc), sizeof(rxreq));
255 netdev->rx_ring.req_cons = ++rc;
256
257 page = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
258 netdev->xendev.dom,
259 rxreq.gref, PROT_WRITE);
260 if (page == NULL) {
261 xen_pv_printf(&netdev->xendev, 0,
262 "error: rx gref dereference failed (%d)\n",
263 rxreq.gref);
264 net_rx_response(netdev, &rxreq, NETIF_RSP_ERROR, 0, 0, 0);
265 return -1;
266 }
267 memcpy(page + NET_IP_ALIGN, buf, size);
268 xengnttab_unmap(netdev->xendev.gnttabdev, page, 1);
269 net_rx_response(netdev, &rxreq, NETIF_RSP_OKAY, NET_IP_ALIGN, size, 0);
270
271 return size;
272 }
273
274 /* ------------------------------------------------------------- */
275
276 static NetClientInfo net_xen_info = {
277 .type = NET_CLIENT_DRIVER_NIC,
278 .size = sizeof(NICState),
279 .receive = net_rx_packet,
280 };
281
282 static int net_init(struct XenDevice *xendev)
283 {
284 struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev);
285
286 /* read xenstore entries */
287 if (netdev->mac == NULL) {
288 netdev->mac = xenstore_read_be_str(&netdev->xendev, "mac");
289 }
290
291 /* do we have all we need? */
292 if (netdev->mac == NULL) {
293 return -1;
294 }
295
296 if (net_parse_macaddr(netdev->conf.macaddr.a, netdev->mac) < 0) {
297 return -1;
298 }
299
300 netdev->nic = qemu_new_nic(&net_xen_info, &netdev->conf,
301 "xen", NULL, netdev);
302
303 snprintf(qemu_get_queue(netdev->nic)->info_str,
304 sizeof(qemu_get_queue(netdev->nic)->info_str),
305 "nic: xenbus vif macaddr=%s", netdev->mac);
306
307 /* fill info */
308 xenstore_write_be_int(&netdev->xendev, "feature-rx-copy", 1);
309 xenstore_write_be_int(&netdev->xendev, "feature-rx-flip", 0);
310
311 return 0;
312 }
313
314 static int net_connect(struct XenDevice *xendev)
315 {
316 struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev);
317 int rx_copy;
318
319 if (xenstore_read_fe_int(&netdev->xendev, "tx-ring-ref",
320 &netdev->tx_ring_ref) == -1) {
321 return -1;
322 }
323 if (xenstore_read_fe_int(&netdev->xendev, "rx-ring-ref",
324 &netdev->rx_ring_ref) == -1) {
325 return 1;
326 }
327 if (xenstore_read_fe_int(&netdev->xendev, "event-channel",
328 &netdev->xendev.remote_port) == -1) {
329 return -1;
330 }
331
332 if (xenstore_read_fe_int(&netdev->xendev, "request-rx-copy", &rx_copy) == -1) {
333 rx_copy = 0;
334 }
335 if (rx_copy == 0) {
336 xen_pv_printf(&netdev->xendev, 0,
337 "frontend doesn't support rx-copy.\n");
338 return -1;
339 }
340
341 netdev->txs = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
342 netdev->xendev.dom,
343 netdev->tx_ring_ref,
344 PROT_READ | PROT_WRITE);
345 if (!netdev->txs) {
346 return -1;
347 }
348 netdev->rxs = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
349 netdev->xendev.dom,
350 netdev->rx_ring_ref,
351 PROT_READ | PROT_WRITE);
352 if (!netdev->rxs) {
353 xengnttab_unmap(netdev->xendev.gnttabdev, netdev->txs, 1);
354 netdev->txs = NULL;
355 return -1;
356 }
357 BACK_RING_INIT(&netdev->tx_ring, netdev->txs, XC_PAGE_SIZE);
358 BACK_RING_INIT(&netdev->rx_ring, netdev->rxs, XC_PAGE_SIZE);
359
360 xen_be_bind_evtchn(&netdev->xendev);
361
362 xen_pv_printf(&netdev->xendev, 1, "ok: tx-ring-ref %d, rx-ring-ref %d, "
363 "remote port %d, local port %d\n",
364 netdev->tx_ring_ref, netdev->rx_ring_ref,
365 netdev->xendev.remote_port, netdev->xendev.local_port);
366
367 net_tx_packets(netdev);
368 return 0;
369 }
370
371 static void net_disconnect(struct XenDevice *xendev)
372 {
373 struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev);
374
375 xen_pv_unbind_evtchn(&netdev->xendev);
376
377 if (netdev->txs) {
378 xengnttab_unmap(netdev->xendev.gnttabdev, netdev->txs, 1);
379 netdev->txs = NULL;
380 }
381 if (netdev->rxs) {
382 xengnttab_unmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
383 netdev->rxs = NULL;
384 }
385 }
386
387 static void net_event(struct XenDevice *xendev)
388 {
389 struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev);
390 net_tx_packets(netdev);
391 qemu_flush_queued_packets(qemu_get_queue(netdev->nic));
392 }
393
394 static int net_free(struct XenDevice *xendev)
395 {
396 struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev);
397
398 if (netdev->nic) {
399 qemu_del_nic(netdev->nic);
400 netdev->nic = NULL;
401 }
402 g_free(netdev->mac);
403 netdev->mac = NULL;
404 return 0;
405 }
406
407 /* ------------------------------------------------------------- */
408
409 struct XenDevOps xen_netdev_ops = {
410 .size = sizeof(struct XenNetDev),
411 .flags = DEVOPS_FLAG_NEED_GNTDEV,
412 .init = net_init,
413 .initialise = net_connect,
414 .event = net_event,
415 .disconnect = net_disconnect,
416 .free = net_free,
417 };
AR7 emulation for QEMU