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3a4d5c94 MT |
1 | /* Copyright (C) 2009 Red Hat, Inc. |
2 | * Author: Michael S. Tsirkin <mst@redhat.com> | |
3 | * | |
4 | * This work is licensed under the terms of the GNU GPL, version 2. | |
5 | * | |
6 | * virtio-net server in host kernel. | |
7 | */ | |
8 | ||
9 | #include <linux/compat.h> | |
10 | #include <linux/eventfd.h> | |
11 | #include <linux/vhost.h> | |
12 | #include <linux/virtio_net.h> | |
3a4d5c94 MT |
13 | #include <linux/miscdevice.h> |
14 | #include <linux/module.h> | |
15 | #include <linux/mutex.h> | |
16 | #include <linux/workqueue.h> | |
17 | #include <linux/rcupdate.h> | |
18 | #include <linux/file.h> | |
5a0e3ad6 | 19 | #include <linux/slab.h> |
3a4d5c94 MT |
20 | |
21 | #include <linux/net.h> | |
22 | #include <linux/if_packet.h> | |
23 | #include <linux/if_arp.h> | |
24 | #include <linux/if_tun.h> | |
501c774c | 25 | #include <linux/if_macvlan.h> |
3a4d5c94 MT |
26 | |
27 | #include <net/sock.h> | |
28 | ||
29 | #include "vhost.h" | |
30 | ||
31 | /* Max number of bytes transferred before requeueing the job. | |
32 | * Using this limit prevents one virtqueue from starving others. */ | |
33 | #define VHOST_NET_WEIGHT 0x80000 | |
34 | ||
35 | enum { | |
36 | VHOST_NET_VQ_RX = 0, | |
37 | VHOST_NET_VQ_TX = 1, | |
38 | VHOST_NET_VQ_MAX = 2, | |
39 | }; | |
40 | ||
41 | enum vhost_net_poll_state { | |
42 | VHOST_NET_POLL_DISABLED = 0, | |
43 | VHOST_NET_POLL_STARTED = 1, | |
44 | VHOST_NET_POLL_STOPPED = 2, | |
45 | }; | |
46 | ||
47 | struct vhost_net { | |
48 | struct vhost_dev dev; | |
49 | struct vhost_virtqueue vqs[VHOST_NET_VQ_MAX]; | |
50 | struct vhost_poll poll[VHOST_NET_VQ_MAX]; | |
51 | /* Tells us whether we are polling a socket for TX. | |
52 | * We only do this when socket buffer fills up. | |
53 | * Protected by tx vq lock. */ | |
54 | enum vhost_net_poll_state tx_poll_state; | |
55 | }; | |
56 | ||
57 | /* Pop first len bytes from iovec. Return number of segments used. */ | |
58 | static int move_iovec_hdr(struct iovec *from, struct iovec *to, | |
59 | size_t len, int iov_count) | |
60 | { | |
61 | int seg = 0; | |
62 | size_t size; | |
63 | while (len && seg < iov_count) { | |
64 | size = min(from->iov_len, len); | |
65 | to->iov_base = from->iov_base; | |
66 | to->iov_len = size; | |
67 | from->iov_len -= size; | |
68 | from->iov_base += size; | |
69 | len -= size; | |
70 | ++from; | |
71 | ++to; | |
72 | ++seg; | |
73 | } | |
74 | return seg; | |
75 | } | |
8dd014ad DS |
76 | /* Copy iovec entries for len bytes from iovec. */ |
77 | static void copy_iovec_hdr(const struct iovec *from, struct iovec *to, | |
78 | size_t len, int iovcount) | |
79 | { | |
80 | int seg = 0; | |
81 | size_t size; | |
82 | while (len && seg < iovcount) { | |
83 | size = min(from->iov_len, len); | |
84 | to->iov_base = from->iov_base; | |
85 | to->iov_len = size; | |
86 | len -= size; | |
87 | ++from; | |
88 | ++to; | |
89 | ++seg; | |
90 | } | |
91 | } | |
3a4d5c94 MT |
92 | |
93 | /* Caller must have TX VQ lock */ | |
94 | static void tx_poll_stop(struct vhost_net *net) | |
95 | { | |
96 | if (likely(net->tx_poll_state != VHOST_NET_POLL_STARTED)) | |
97 | return; | |
98 | vhost_poll_stop(net->poll + VHOST_NET_VQ_TX); | |
99 | net->tx_poll_state = VHOST_NET_POLL_STOPPED; | |
100 | } | |
101 | ||
102 | /* Caller must have TX VQ lock */ | |
103 | static void tx_poll_start(struct vhost_net *net, struct socket *sock) | |
104 | { | |
105 | if (unlikely(net->tx_poll_state != VHOST_NET_POLL_STOPPED)) | |
106 | return; | |
107 | vhost_poll_start(net->poll + VHOST_NET_VQ_TX, sock->file); | |
108 | net->tx_poll_state = VHOST_NET_POLL_STARTED; | |
109 | } | |
110 | ||
111 | /* Expects to be always run from workqueue - which acts as | |
112 | * read-size critical section for our kind of RCU. */ | |
113 | static void handle_tx(struct vhost_net *net) | |
114 | { | |
115 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX]; | |
d5675bd2 MT |
116 | unsigned out, in, s; |
117 | int head; | |
3a4d5c94 MT |
118 | struct msghdr msg = { |
119 | .msg_name = NULL, | |
120 | .msg_namelen = 0, | |
121 | .msg_control = NULL, | |
122 | .msg_controllen = 0, | |
123 | .msg_iov = vq->iov, | |
124 | .msg_flags = MSG_DONTWAIT, | |
125 | }; | |
126 | size_t len, total_len = 0; | |
127 | int err, wmem; | |
128 | size_t hdr_size; | |
28457ee6 AB |
129 | struct socket *sock; |
130 | ||
5e18247b | 131 | /* TODO: check that we are running from vhost_worker? */ |
11cd1a8b | 132 | sock = rcu_dereference_check(vq->private_data, 1); |
3a4d5c94 MT |
133 | if (!sock) |
134 | return; | |
135 | ||
136 | wmem = atomic_read(&sock->sk->sk_wmem_alloc); | |
39286fa4 SS |
137 | if (wmem >= sock->sk->sk_sndbuf) { |
138 | mutex_lock(&vq->mutex); | |
139 | tx_poll_start(net, sock); | |
140 | mutex_unlock(&vq->mutex); | |
3a4d5c94 | 141 | return; |
39286fa4 | 142 | } |
3a4d5c94 | 143 | |
3a4d5c94 MT |
144 | mutex_lock(&vq->mutex); |
145 | vhost_disable_notify(vq); | |
146 | ||
0e255572 | 147 | if (wmem < sock->sk->sk_sndbuf / 2) |
3a4d5c94 | 148 | tx_poll_stop(net); |
8dd014ad | 149 | hdr_size = vq->vhost_hlen; |
3a4d5c94 MT |
150 | |
151 | for (;;) { | |
152 | head = vhost_get_vq_desc(&net->dev, vq, vq->iov, | |
153 | ARRAY_SIZE(vq->iov), | |
154 | &out, &in, | |
155 | NULL, NULL); | |
d5675bd2 | 156 | /* On error, stop handling until the next kick. */ |
7b3384fc | 157 | if (unlikely(head < 0)) |
d5675bd2 | 158 | break; |
3a4d5c94 MT |
159 | /* Nothing new? Wait for eventfd to tell us they refilled. */ |
160 | if (head == vq->num) { | |
161 | wmem = atomic_read(&sock->sk->sk_wmem_alloc); | |
162 | if (wmem >= sock->sk->sk_sndbuf * 3 / 4) { | |
163 | tx_poll_start(net, sock); | |
164 | set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); | |
165 | break; | |
166 | } | |
167 | if (unlikely(vhost_enable_notify(vq))) { | |
168 | vhost_disable_notify(vq); | |
169 | continue; | |
170 | } | |
171 | break; | |
172 | } | |
173 | if (in) { | |
174 | vq_err(vq, "Unexpected descriptor format for TX: " | |
175 | "out %d, int %d\n", out, in); | |
176 | break; | |
177 | } | |
178 | /* Skip header. TODO: support TSO. */ | |
179 | s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, out); | |
180 | msg.msg_iovlen = out; | |
181 | len = iov_length(vq->iov, out); | |
182 | /* Sanity check */ | |
183 | if (!len) { | |
184 | vq_err(vq, "Unexpected header len for TX: " | |
185 | "%zd expected %zd\n", | |
186 | iov_length(vq->hdr, s), hdr_size); | |
187 | break; | |
188 | } | |
189 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ | |
190 | err = sock->ops->sendmsg(NULL, sock, &msg, len); | |
191 | if (unlikely(err < 0)) { | |
8dd014ad | 192 | vhost_discard_vq_desc(vq, 1); |
3a4d5c94 MT |
193 | tx_poll_start(net, sock); |
194 | break; | |
195 | } | |
196 | if (err != len) | |
95c0ec6a MT |
197 | pr_debug("Truncated TX packet: " |
198 | " len %d != %zd\n", err, len); | |
3a4d5c94 MT |
199 | vhost_add_used_and_signal(&net->dev, vq, head, 0); |
200 | total_len += len; | |
201 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
202 | vhost_poll_queue(&vq->poll); | |
203 | break; | |
204 | } | |
205 | } | |
206 | ||
207 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
208 | } |
209 | ||
8dd014ad DS |
210 | static int peek_head_len(struct sock *sk) |
211 | { | |
212 | struct sk_buff *head; | |
213 | int len = 0; | |
214 | ||
215 | lock_sock(sk); | |
216 | head = skb_peek(&sk->sk_receive_queue); | |
217 | if (head) | |
218 | len = head->len; | |
219 | release_sock(sk); | |
220 | return len; | |
221 | } | |
222 | ||
223 | /* This is a multi-buffer version of vhost_get_desc, that works if | |
224 | * vq has read descriptors only. | |
225 | * @vq - the relevant virtqueue | |
226 | * @datalen - data length we'll be reading | |
227 | * @iovcount - returned count of io vectors we fill | |
228 | * @log - vhost log | |
229 | * @log_num - log offset | |
230 | * returns number of buffer heads allocated, negative on error | |
231 | */ | |
232 | static int get_rx_bufs(struct vhost_virtqueue *vq, | |
233 | struct vring_used_elem *heads, | |
234 | int datalen, | |
235 | unsigned *iovcount, | |
236 | struct vhost_log *log, | |
237 | unsigned *log_num) | |
238 | { | |
239 | unsigned int out, in; | |
240 | int seg = 0; | |
241 | int headcount = 0; | |
242 | unsigned d; | |
243 | int r, nlogs = 0; | |
244 | ||
245 | while (datalen > 0) { | |
e0e9b406 | 246 | if (unlikely(seg >= UIO_MAXIOV)) { |
8dd014ad DS |
247 | r = -ENOBUFS; |
248 | goto err; | |
249 | } | |
250 | d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, | |
251 | ARRAY_SIZE(vq->iov) - seg, &out, | |
252 | &in, log, log_num); | |
253 | if (d == vq->num) { | |
254 | r = 0; | |
255 | goto err; | |
256 | } | |
257 | if (unlikely(out || in <= 0)) { | |
258 | vq_err(vq, "unexpected descriptor format for RX: " | |
259 | "out %d, in %d\n", out, in); | |
260 | r = -EINVAL; | |
261 | goto err; | |
262 | } | |
263 | if (unlikely(log)) { | |
264 | nlogs += *log_num; | |
265 | log += *log_num; | |
266 | } | |
267 | heads[headcount].id = d; | |
268 | heads[headcount].len = iov_length(vq->iov + seg, in); | |
269 | datalen -= heads[headcount].len; | |
270 | ++headcount; | |
271 | seg += in; | |
272 | } | |
273 | heads[headcount - 1].len += datalen; | |
274 | *iovcount = seg; | |
275 | if (unlikely(log)) | |
276 | *log_num = nlogs; | |
277 | return headcount; | |
278 | err: | |
279 | vhost_discard_vq_desc(vq, headcount); | |
280 | return r; | |
281 | } | |
282 | ||
3a4d5c94 MT |
283 | /* Expects to be always run from workqueue - which acts as |
284 | * read-size critical section for our kind of RCU. */ | |
8dd014ad | 285 | static void handle_rx_big(struct vhost_net *net) |
3a4d5c94 MT |
286 | { |
287 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX]; | |
d5675bd2 MT |
288 | unsigned out, in, log, s; |
289 | int head; | |
3a4d5c94 MT |
290 | struct vhost_log *vq_log; |
291 | struct msghdr msg = { | |
292 | .msg_name = NULL, | |
293 | .msg_namelen = 0, | |
294 | .msg_control = NULL, /* FIXME: get and handle RX aux data. */ | |
295 | .msg_controllen = 0, | |
296 | .msg_iov = vq->iov, | |
297 | .msg_flags = MSG_DONTWAIT, | |
298 | }; | |
299 | ||
300 | struct virtio_net_hdr hdr = { | |
301 | .flags = 0, | |
302 | .gso_type = VIRTIO_NET_HDR_GSO_NONE | |
303 | }; | |
304 | ||
305 | size_t len, total_len = 0; | |
306 | int err; | |
307 | size_t hdr_size; | |
5e18247b MT |
308 | /* TODO: check that we are running from vhost_worker? */ |
309 | struct socket *sock = rcu_dereference_check(vq->private_data, 1); | |
3a4d5c94 MT |
310 | if (!sock || skb_queue_empty(&sock->sk->sk_receive_queue)) |
311 | return; | |
312 | ||
3a4d5c94 MT |
313 | mutex_lock(&vq->mutex); |
314 | vhost_disable_notify(vq); | |
8dd014ad | 315 | hdr_size = vq->vhost_hlen; |
3a4d5c94 MT |
316 | |
317 | vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? | |
318 | vq->log : NULL; | |
319 | ||
320 | for (;;) { | |
321 | head = vhost_get_vq_desc(&net->dev, vq, vq->iov, | |
322 | ARRAY_SIZE(vq->iov), | |
323 | &out, &in, | |
324 | vq_log, &log); | |
d5675bd2 | 325 | /* On error, stop handling until the next kick. */ |
7b3384fc | 326 | if (unlikely(head < 0)) |
d5675bd2 | 327 | break; |
3a4d5c94 MT |
328 | /* OK, now we need to know about added descriptors. */ |
329 | if (head == vq->num) { | |
330 | if (unlikely(vhost_enable_notify(vq))) { | |
331 | /* They have slipped one in as we were | |
332 | * doing that: check again. */ | |
333 | vhost_disable_notify(vq); | |
334 | continue; | |
335 | } | |
336 | /* Nothing new? Wait for eventfd to tell us | |
337 | * they refilled. */ | |
338 | break; | |
339 | } | |
340 | /* We don't need to be notified again. */ | |
341 | if (out) { | |
342 | vq_err(vq, "Unexpected descriptor format for RX: " | |
343 | "out %d, int %d\n", | |
344 | out, in); | |
345 | break; | |
346 | } | |
347 | /* Skip header. TODO: support TSO/mergeable rx buffers. */ | |
348 | s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, in); | |
349 | msg.msg_iovlen = in; | |
350 | len = iov_length(vq->iov, in); | |
351 | /* Sanity check */ | |
352 | if (!len) { | |
353 | vq_err(vq, "Unexpected header len for RX: " | |
354 | "%zd expected %zd\n", | |
355 | iov_length(vq->hdr, s), hdr_size); | |
356 | break; | |
357 | } | |
358 | err = sock->ops->recvmsg(NULL, sock, &msg, | |
359 | len, MSG_DONTWAIT | MSG_TRUNC); | |
360 | /* TODO: Check specific error and bomb out unless EAGAIN? */ | |
361 | if (err < 0) { | |
8dd014ad | 362 | vhost_discard_vq_desc(vq, 1); |
3a4d5c94 MT |
363 | break; |
364 | } | |
365 | /* TODO: Should check and handle checksum. */ | |
366 | if (err > len) { | |
95c0ec6a MT |
367 | pr_debug("Discarded truncated rx packet: " |
368 | " len %d > %zd\n", err, len); | |
8dd014ad | 369 | vhost_discard_vq_desc(vq, 1); |
3a4d5c94 MT |
370 | continue; |
371 | } | |
372 | len = err; | |
373 | err = memcpy_toiovec(vq->hdr, (unsigned char *)&hdr, hdr_size); | |
374 | if (err) { | |
375 | vq_err(vq, "Unable to write vnet_hdr at addr %p: %d\n", | |
376 | vq->iov->iov_base, err); | |
377 | break; | |
378 | } | |
379 | len += hdr_size; | |
380 | vhost_add_used_and_signal(&net->dev, vq, head, len); | |
381 | if (unlikely(vq_log)) | |
382 | vhost_log_write(vq, vq_log, log, len); | |
383 | total_len += len; | |
384 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
385 | vhost_poll_queue(&vq->poll); | |
386 | break; | |
387 | } | |
388 | } | |
389 | ||
390 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
391 | } |
392 | ||
8dd014ad DS |
393 | /* Expects to be always run from workqueue - which acts as |
394 | * read-size critical section for our kind of RCU. */ | |
395 | static void handle_rx_mergeable(struct vhost_net *net) | |
3a4d5c94 | 396 | { |
8dd014ad DS |
397 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX]; |
398 | unsigned uninitialized_var(in), log; | |
399 | struct vhost_log *vq_log; | |
400 | struct msghdr msg = { | |
401 | .msg_name = NULL, | |
402 | .msg_namelen = 0, | |
403 | .msg_control = NULL, /* FIXME: get and handle RX aux data. */ | |
404 | .msg_controllen = 0, | |
405 | .msg_iov = vq->iov, | |
406 | .msg_flags = MSG_DONTWAIT, | |
407 | }; | |
408 | ||
409 | struct virtio_net_hdr_mrg_rxbuf hdr = { | |
410 | .hdr.flags = 0, | |
411 | .hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE | |
412 | }; | |
413 | ||
414 | size_t total_len = 0; | |
415 | int err, headcount; | |
416 | size_t vhost_hlen, sock_hlen; | |
417 | size_t vhost_len, sock_len; | |
5e18247b MT |
418 | /* TODO: check that we are running from vhost_worker? */ |
419 | struct socket *sock = rcu_dereference_check(vq->private_data, 1); | |
8dd014ad DS |
420 | if (!sock || skb_queue_empty(&sock->sk->sk_receive_queue)) |
421 | return; | |
422 | ||
8dd014ad DS |
423 | mutex_lock(&vq->mutex); |
424 | vhost_disable_notify(vq); | |
425 | vhost_hlen = vq->vhost_hlen; | |
426 | sock_hlen = vq->sock_hlen; | |
427 | ||
428 | vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? | |
429 | vq->log : NULL; | |
430 | ||
431 | while ((sock_len = peek_head_len(sock->sk))) { | |
432 | sock_len += sock_hlen; | |
433 | vhost_len = sock_len + vhost_hlen; | |
434 | headcount = get_rx_bufs(vq, vq->heads, vhost_len, | |
435 | &in, vq_log, &log); | |
436 | /* On error, stop handling until the next kick. */ | |
437 | if (unlikely(headcount < 0)) | |
438 | break; | |
439 | /* OK, now we need to know about added descriptors. */ | |
440 | if (!headcount) { | |
441 | if (unlikely(vhost_enable_notify(vq))) { | |
442 | /* They have slipped one in as we were | |
443 | * doing that: check again. */ | |
444 | vhost_disable_notify(vq); | |
445 | continue; | |
446 | } | |
447 | /* Nothing new? Wait for eventfd to tell us | |
448 | * they refilled. */ | |
449 | break; | |
450 | } | |
451 | /* We don't need to be notified again. */ | |
452 | if (unlikely((vhost_hlen))) | |
453 | /* Skip header. TODO: support TSO. */ | |
454 | move_iovec_hdr(vq->iov, vq->hdr, vhost_hlen, in); | |
455 | else | |
456 | /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: | |
a290aec8 | 457 | * needed because recvmsg can modify msg_iov. */ |
8dd014ad DS |
458 | copy_iovec_hdr(vq->iov, vq->hdr, sock_hlen, in); |
459 | msg.msg_iovlen = in; | |
460 | err = sock->ops->recvmsg(NULL, sock, &msg, | |
461 | sock_len, MSG_DONTWAIT | MSG_TRUNC); | |
462 | /* Userspace might have consumed the packet meanwhile: | |
463 | * it's not supposed to do this usually, but might be hard | |
464 | * to prevent. Discard data we got (if any) and keep going. */ | |
465 | if (unlikely(err != sock_len)) { | |
466 | pr_debug("Discarded rx packet: " | |
467 | " len %d, expected %zd\n", err, sock_len); | |
468 | vhost_discard_vq_desc(vq, headcount); | |
469 | continue; | |
470 | } | |
471 | if (unlikely(vhost_hlen) && | |
472 | memcpy_toiovecend(vq->hdr, (unsigned char *)&hdr, 0, | |
473 | vhost_hlen)) { | |
474 | vq_err(vq, "Unable to write vnet_hdr at addr %p\n", | |
475 | vq->iov->iov_base); | |
476 | break; | |
477 | } | |
478 | /* TODO: Should check and handle checksum. */ | |
479 | if (vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF) && | |
480 | memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount, | |
481 | offsetof(typeof(hdr), num_buffers), | |
482 | sizeof hdr.num_buffers)) { | |
483 | vq_err(vq, "Failed num_buffers write"); | |
484 | vhost_discard_vq_desc(vq, headcount); | |
485 | break; | |
486 | } | |
487 | vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, | |
488 | headcount); | |
489 | if (unlikely(vq_log)) | |
490 | vhost_log_write(vq, vq_log, log, vhost_len); | |
491 | total_len += vhost_len; | |
492 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
493 | vhost_poll_queue(&vq->poll); | |
494 | break; | |
495 | } | |
496 | } | |
497 | ||
498 | mutex_unlock(&vq->mutex); | |
8dd014ad DS |
499 | } |
500 | ||
501 | static void handle_rx(struct vhost_net *net) | |
502 | { | |
503 | if (vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF)) | |
504 | handle_rx_mergeable(net); | |
505 | else | |
506 | handle_rx_big(net); | |
507 | } | |
508 | ||
c23f3445 | 509 | static void handle_tx_kick(struct vhost_work *work) |
3a4d5c94 | 510 | { |
c23f3445 TH |
511 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
512 | poll.work); | |
513 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
514 | ||
3a4d5c94 MT |
515 | handle_tx(net); |
516 | } | |
517 | ||
c23f3445 | 518 | static void handle_rx_kick(struct vhost_work *work) |
3a4d5c94 | 519 | { |
c23f3445 TH |
520 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
521 | poll.work); | |
522 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
523 | ||
3a4d5c94 MT |
524 | handle_rx(net); |
525 | } | |
526 | ||
c23f3445 | 527 | static void handle_tx_net(struct vhost_work *work) |
3a4d5c94 | 528 | { |
c23f3445 TH |
529 | struct vhost_net *net = container_of(work, struct vhost_net, |
530 | poll[VHOST_NET_VQ_TX].work); | |
3a4d5c94 MT |
531 | handle_tx(net); |
532 | } | |
533 | ||
c23f3445 | 534 | static void handle_rx_net(struct vhost_work *work) |
3a4d5c94 | 535 | { |
c23f3445 TH |
536 | struct vhost_net *net = container_of(work, struct vhost_net, |
537 | poll[VHOST_NET_VQ_RX].work); | |
3a4d5c94 MT |
538 | handle_rx(net); |
539 | } | |
540 | ||
541 | static int vhost_net_open(struct inode *inode, struct file *f) | |
542 | { | |
543 | struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); | |
c23f3445 | 544 | struct vhost_dev *dev; |
3a4d5c94 | 545 | int r; |
c23f3445 | 546 | |
3a4d5c94 MT |
547 | if (!n) |
548 | return -ENOMEM; | |
c23f3445 TH |
549 | |
550 | dev = &n->dev; | |
3a4d5c94 MT |
551 | n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick; |
552 | n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick; | |
c23f3445 | 553 | r = vhost_dev_init(dev, n->vqs, VHOST_NET_VQ_MAX); |
3a4d5c94 MT |
554 | if (r < 0) { |
555 | kfree(n); | |
556 | return r; | |
557 | } | |
558 | ||
c23f3445 TH |
559 | vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); |
560 | vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); | |
3a4d5c94 MT |
561 | n->tx_poll_state = VHOST_NET_POLL_DISABLED; |
562 | ||
563 | f->private_data = n; | |
564 | ||
565 | return 0; | |
566 | } | |
567 | ||
568 | static void vhost_net_disable_vq(struct vhost_net *n, | |
569 | struct vhost_virtqueue *vq) | |
570 | { | |
571 | if (!vq->private_data) | |
572 | return; | |
573 | if (vq == n->vqs + VHOST_NET_VQ_TX) { | |
574 | tx_poll_stop(n); | |
575 | n->tx_poll_state = VHOST_NET_POLL_DISABLED; | |
576 | } else | |
577 | vhost_poll_stop(n->poll + VHOST_NET_VQ_RX); | |
578 | } | |
579 | ||
580 | static void vhost_net_enable_vq(struct vhost_net *n, | |
581 | struct vhost_virtqueue *vq) | |
582 | { | |
28457ee6 AB |
583 | struct socket *sock; |
584 | ||
585 | sock = rcu_dereference_protected(vq->private_data, | |
586 | lockdep_is_held(&vq->mutex)); | |
3a4d5c94 MT |
587 | if (!sock) |
588 | return; | |
589 | if (vq == n->vqs + VHOST_NET_VQ_TX) { | |
590 | n->tx_poll_state = VHOST_NET_POLL_STOPPED; | |
591 | tx_poll_start(n, sock); | |
592 | } else | |
593 | vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file); | |
594 | } | |
595 | ||
596 | static struct socket *vhost_net_stop_vq(struct vhost_net *n, | |
597 | struct vhost_virtqueue *vq) | |
598 | { | |
599 | struct socket *sock; | |
600 | ||
601 | mutex_lock(&vq->mutex); | |
28457ee6 AB |
602 | sock = rcu_dereference_protected(vq->private_data, |
603 | lockdep_is_held(&vq->mutex)); | |
3a4d5c94 MT |
604 | vhost_net_disable_vq(n, vq); |
605 | rcu_assign_pointer(vq->private_data, NULL); | |
606 | mutex_unlock(&vq->mutex); | |
607 | return sock; | |
608 | } | |
609 | ||
610 | static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, | |
611 | struct socket **rx_sock) | |
612 | { | |
613 | *tx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_TX); | |
614 | *rx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_RX); | |
615 | } | |
616 | ||
617 | static void vhost_net_flush_vq(struct vhost_net *n, int index) | |
618 | { | |
619 | vhost_poll_flush(n->poll + index); | |
620 | vhost_poll_flush(&n->dev.vqs[index].poll); | |
621 | } | |
622 | ||
623 | static void vhost_net_flush(struct vhost_net *n) | |
624 | { | |
625 | vhost_net_flush_vq(n, VHOST_NET_VQ_TX); | |
626 | vhost_net_flush_vq(n, VHOST_NET_VQ_RX); | |
627 | } | |
628 | ||
629 | static int vhost_net_release(struct inode *inode, struct file *f) | |
630 | { | |
631 | struct vhost_net *n = f->private_data; | |
632 | struct socket *tx_sock; | |
633 | struct socket *rx_sock; | |
634 | ||
635 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
636 | vhost_net_flush(n); | |
637 | vhost_dev_cleanup(&n->dev); | |
638 | if (tx_sock) | |
639 | fput(tx_sock->file); | |
640 | if (rx_sock) | |
641 | fput(rx_sock->file); | |
642 | /* We do an extra flush before freeing memory, | |
643 | * since jobs can re-queue themselves. */ | |
644 | vhost_net_flush(n); | |
645 | kfree(n); | |
646 | return 0; | |
647 | } | |
648 | ||
649 | static struct socket *get_raw_socket(int fd) | |
650 | { | |
651 | struct { | |
652 | struct sockaddr_ll sa; | |
653 | char buf[MAX_ADDR_LEN]; | |
654 | } uaddr; | |
655 | int uaddr_len = sizeof uaddr, r; | |
656 | struct socket *sock = sockfd_lookup(fd, &r); | |
657 | if (!sock) | |
658 | return ERR_PTR(-ENOTSOCK); | |
659 | ||
660 | /* Parameter checking */ | |
661 | if (sock->sk->sk_type != SOCK_RAW) { | |
662 | r = -ESOCKTNOSUPPORT; | |
663 | goto err; | |
664 | } | |
665 | ||
666 | r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, | |
667 | &uaddr_len, 0); | |
668 | if (r) | |
669 | goto err; | |
670 | ||
671 | if (uaddr.sa.sll_family != AF_PACKET) { | |
672 | r = -EPFNOSUPPORT; | |
673 | goto err; | |
674 | } | |
675 | return sock; | |
676 | err: | |
677 | fput(sock->file); | |
678 | return ERR_PTR(r); | |
679 | } | |
680 | ||
501c774c | 681 | static struct socket *get_tap_socket(int fd) |
3a4d5c94 MT |
682 | { |
683 | struct file *file = fget(fd); | |
684 | struct socket *sock; | |
685 | if (!file) | |
686 | return ERR_PTR(-EBADF); | |
687 | sock = tun_get_socket(file); | |
501c774c AB |
688 | if (!IS_ERR(sock)) |
689 | return sock; | |
690 | sock = macvtap_get_socket(file); | |
3a4d5c94 MT |
691 | if (IS_ERR(sock)) |
692 | fput(file); | |
693 | return sock; | |
694 | } | |
695 | ||
696 | static struct socket *get_socket(int fd) | |
697 | { | |
698 | struct socket *sock; | |
699 | /* special case to disable backend */ | |
700 | if (fd == -1) | |
701 | return NULL; | |
702 | sock = get_raw_socket(fd); | |
703 | if (!IS_ERR(sock)) | |
704 | return sock; | |
501c774c | 705 | sock = get_tap_socket(fd); |
3a4d5c94 MT |
706 | if (!IS_ERR(sock)) |
707 | return sock; | |
708 | return ERR_PTR(-ENOTSOCK); | |
709 | } | |
710 | ||
711 | static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) | |
712 | { | |
713 | struct socket *sock, *oldsock; | |
714 | struct vhost_virtqueue *vq; | |
715 | int r; | |
716 | ||
717 | mutex_lock(&n->dev.mutex); | |
718 | r = vhost_dev_check_owner(&n->dev); | |
719 | if (r) | |
720 | goto err; | |
721 | ||
722 | if (index >= VHOST_NET_VQ_MAX) { | |
723 | r = -ENOBUFS; | |
724 | goto err; | |
725 | } | |
726 | vq = n->vqs + index; | |
727 | mutex_lock(&vq->mutex); | |
728 | ||
729 | /* Verify that ring has been setup correctly. */ | |
730 | if (!vhost_vq_access_ok(vq)) { | |
731 | r = -EFAULT; | |
1dace8c8 | 732 | goto err_vq; |
3a4d5c94 MT |
733 | } |
734 | sock = get_socket(fd); | |
735 | if (IS_ERR(sock)) { | |
736 | r = PTR_ERR(sock); | |
1dace8c8 | 737 | goto err_vq; |
3a4d5c94 MT |
738 | } |
739 | ||
740 | /* start polling new socket */ | |
28457ee6 AB |
741 | oldsock = rcu_dereference_protected(vq->private_data, |
742 | lockdep_is_held(&vq->mutex)); | |
11fe8839 | 743 | if (sock != oldsock) { |
dd1f4078 JD |
744 | vhost_net_disable_vq(n, vq); |
745 | rcu_assign_pointer(vq->private_data, sock); | |
746 | vhost_net_enable_vq(n, vq); | |
747 | } | |
3a4d5c94 | 748 | |
1680e906 MT |
749 | mutex_unlock(&vq->mutex); |
750 | ||
3a4d5c94 MT |
751 | if (oldsock) { |
752 | vhost_net_flush_vq(n, index); | |
753 | fput(oldsock->file); | |
754 | } | |
1dace8c8 | 755 | |
1680e906 MT |
756 | mutex_unlock(&n->dev.mutex); |
757 | return 0; | |
758 | ||
1dace8c8 JD |
759 | err_vq: |
760 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
761 | err: |
762 | mutex_unlock(&n->dev.mutex); | |
763 | return r; | |
764 | } | |
765 | ||
766 | static long vhost_net_reset_owner(struct vhost_net *n) | |
767 | { | |
768 | struct socket *tx_sock = NULL; | |
769 | struct socket *rx_sock = NULL; | |
770 | long err; | |
771 | mutex_lock(&n->dev.mutex); | |
772 | err = vhost_dev_check_owner(&n->dev); | |
773 | if (err) | |
774 | goto done; | |
775 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
776 | vhost_net_flush(n); | |
777 | err = vhost_dev_reset_owner(&n->dev); | |
778 | done: | |
779 | mutex_unlock(&n->dev.mutex); | |
780 | if (tx_sock) | |
781 | fput(tx_sock->file); | |
782 | if (rx_sock) | |
783 | fput(rx_sock->file); | |
784 | return err; | |
785 | } | |
786 | ||
787 | static int vhost_net_set_features(struct vhost_net *n, u64 features) | |
788 | { | |
8dd014ad | 789 | size_t vhost_hlen, sock_hlen, hdr_len; |
3a4d5c94 | 790 | int i; |
8dd014ad DS |
791 | |
792 | hdr_len = (features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? | |
793 | sizeof(struct virtio_net_hdr_mrg_rxbuf) : | |
794 | sizeof(struct virtio_net_hdr); | |
795 | if (features & (1 << VHOST_NET_F_VIRTIO_NET_HDR)) { | |
796 | /* vhost provides vnet_hdr */ | |
797 | vhost_hlen = hdr_len; | |
798 | sock_hlen = 0; | |
799 | } else { | |
800 | /* socket provides vnet_hdr */ | |
801 | vhost_hlen = 0; | |
802 | sock_hlen = hdr_len; | |
803 | } | |
3a4d5c94 MT |
804 | mutex_lock(&n->dev.mutex); |
805 | if ((features & (1 << VHOST_F_LOG_ALL)) && | |
806 | !vhost_log_access_ok(&n->dev)) { | |
807 | mutex_unlock(&n->dev.mutex); | |
808 | return -EFAULT; | |
809 | } | |
810 | n->dev.acked_features = features; | |
811 | smp_wmb(); | |
812 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { | |
813 | mutex_lock(&n->vqs[i].mutex); | |
8dd014ad DS |
814 | n->vqs[i].vhost_hlen = vhost_hlen; |
815 | n->vqs[i].sock_hlen = sock_hlen; | |
3a4d5c94 MT |
816 | mutex_unlock(&n->vqs[i].mutex); |
817 | } | |
818 | vhost_net_flush(n); | |
819 | mutex_unlock(&n->dev.mutex); | |
820 | return 0; | |
821 | } | |
822 | ||
823 | static long vhost_net_ioctl(struct file *f, unsigned int ioctl, | |
824 | unsigned long arg) | |
825 | { | |
826 | struct vhost_net *n = f->private_data; | |
827 | void __user *argp = (void __user *)arg; | |
828 | u64 __user *featurep = argp; | |
829 | struct vhost_vring_file backend; | |
830 | u64 features; | |
831 | int r; | |
832 | switch (ioctl) { | |
833 | case VHOST_NET_SET_BACKEND: | |
d3553a52 TY |
834 | if (copy_from_user(&backend, argp, sizeof backend)) |
835 | return -EFAULT; | |
3a4d5c94 MT |
836 | return vhost_net_set_backend(n, backend.index, backend.fd); |
837 | case VHOST_GET_FEATURES: | |
838 | features = VHOST_FEATURES; | |
d3553a52 TY |
839 | if (copy_to_user(featurep, &features, sizeof features)) |
840 | return -EFAULT; | |
841 | return 0; | |
3a4d5c94 | 842 | case VHOST_SET_FEATURES: |
d3553a52 TY |
843 | if (copy_from_user(&features, featurep, sizeof features)) |
844 | return -EFAULT; | |
3a4d5c94 MT |
845 | if (features & ~VHOST_FEATURES) |
846 | return -EOPNOTSUPP; | |
847 | return vhost_net_set_features(n, features); | |
848 | case VHOST_RESET_OWNER: | |
849 | return vhost_net_reset_owner(n); | |
850 | default: | |
851 | mutex_lock(&n->dev.mutex); | |
852 | r = vhost_dev_ioctl(&n->dev, ioctl, arg); | |
853 | vhost_net_flush(n); | |
854 | mutex_unlock(&n->dev.mutex); | |
855 | return r; | |
856 | } | |
857 | } | |
858 | ||
859 | #ifdef CONFIG_COMPAT | |
860 | static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, | |
861 | unsigned long arg) | |
862 | { | |
863 | return vhost_net_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); | |
864 | } | |
865 | #endif | |
866 | ||
373a83a6 | 867 | static const struct file_operations vhost_net_fops = { |
3a4d5c94 MT |
868 | .owner = THIS_MODULE, |
869 | .release = vhost_net_release, | |
870 | .unlocked_ioctl = vhost_net_ioctl, | |
871 | #ifdef CONFIG_COMPAT | |
872 | .compat_ioctl = vhost_net_compat_ioctl, | |
873 | #endif | |
874 | .open = vhost_net_open, | |
6038f373 | 875 | .llseek = noop_llseek, |
3a4d5c94 MT |
876 | }; |
877 | ||
878 | static struct miscdevice vhost_net_misc = { | |
79907d89 | 879 | MISC_DYNAMIC_MINOR, |
3a4d5c94 MT |
880 | "vhost-net", |
881 | &vhost_net_fops, | |
882 | }; | |
883 | ||
a8d3782f | 884 | static int vhost_net_init(void) |
3a4d5c94 | 885 | { |
c23f3445 | 886 | return misc_register(&vhost_net_misc); |
3a4d5c94 MT |
887 | } |
888 | module_init(vhost_net_init); | |
889 | ||
a8d3782f | 890 | static void vhost_net_exit(void) |
3a4d5c94 MT |
891 | { |
892 | misc_deregister(&vhost_net_misc); | |
3a4d5c94 MT |
893 | } |
894 | module_exit(vhost_net_exit); | |
895 | ||
896 | MODULE_VERSION("0.0.1"); | |
897 | MODULE_LICENSE("GPL v2"); | |
898 | MODULE_AUTHOR("Michael S. Tsirkin"); | |
899 | MODULE_DESCRIPTION("Host kernel accelerator for virtio net"); |