Commit | Line | Data |
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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; | |
d47effe1 | 63 | |
3a4d5c94 MT |
64 | while (len && seg < iov_count) { |
65 | size = min(from->iov_len, len); | |
66 | to->iov_base = from->iov_base; | |
67 | to->iov_len = size; | |
68 | from->iov_len -= size; | |
69 | from->iov_base += size; | |
70 | len -= size; | |
71 | ++from; | |
72 | ++to; | |
73 | ++seg; | |
74 | } | |
75 | return seg; | |
76 | } | |
8dd014ad DS |
77 | /* Copy iovec entries for len bytes from iovec. */ |
78 | static void copy_iovec_hdr(const struct iovec *from, struct iovec *to, | |
79 | size_t len, int iovcount) | |
80 | { | |
81 | int seg = 0; | |
82 | size_t size; | |
d47effe1 | 83 | |
8dd014ad DS |
84 | while (len && seg < iovcount) { |
85 | size = min(from->iov_len, len); | |
86 | to->iov_base = from->iov_base; | |
87 | to->iov_len = size; | |
88 | len -= size; | |
89 | ++from; | |
90 | ++to; | |
91 | ++seg; | |
92 | } | |
93 | } | |
3a4d5c94 MT |
94 | |
95 | /* Caller must have TX VQ lock */ | |
96 | static void tx_poll_stop(struct vhost_net *net) | |
97 | { | |
98 | if (likely(net->tx_poll_state != VHOST_NET_POLL_STARTED)) | |
99 | return; | |
100 | vhost_poll_stop(net->poll + VHOST_NET_VQ_TX); | |
101 | net->tx_poll_state = VHOST_NET_POLL_STOPPED; | |
102 | } | |
103 | ||
104 | /* Caller must have TX VQ lock */ | |
105 | static void tx_poll_start(struct vhost_net *net, struct socket *sock) | |
106 | { | |
107 | if (unlikely(net->tx_poll_state != VHOST_NET_POLL_STOPPED)) | |
108 | return; | |
109 | vhost_poll_start(net->poll + VHOST_NET_VQ_TX, sock->file); | |
110 | net->tx_poll_state = VHOST_NET_POLL_STARTED; | |
111 | } | |
112 | ||
113 | /* Expects to be always run from workqueue - which acts as | |
114 | * read-size critical section for our kind of RCU. */ | |
115 | static void handle_tx(struct vhost_net *net) | |
116 | { | |
117 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX]; | |
d5675bd2 MT |
118 | unsigned out, in, s; |
119 | int head; | |
3a4d5c94 MT |
120 | struct msghdr msg = { |
121 | .msg_name = NULL, | |
122 | .msg_namelen = 0, | |
123 | .msg_control = NULL, | |
124 | .msg_controllen = 0, | |
125 | .msg_iov = vq->iov, | |
126 | .msg_flags = MSG_DONTWAIT, | |
127 | }; | |
128 | size_t len, total_len = 0; | |
129 | int err, wmem; | |
130 | size_t hdr_size; | |
28457ee6 AB |
131 | struct socket *sock; |
132 | ||
5e18247b | 133 | /* TODO: check that we are running from vhost_worker? */ |
11cd1a8b | 134 | sock = rcu_dereference_check(vq->private_data, 1); |
3a4d5c94 MT |
135 | if (!sock) |
136 | return; | |
137 | ||
138 | wmem = atomic_read(&sock->sk->sk_wmem_alloc); | |
39286fa4 SS |
139 | if (wmem >= sock->sk->sk_sndbuf) { |
140 | mutex_lock(&vq->mutex); | |
141 | tx_poll_start(net, sock); | |
142 | mutex_unlock(&vq->mutex); | |
3a4d5c94 | 143 | return; |
39286fa4 | 144 | } |
3a4d5c94 | 145 | |
3a4d5c94 MT |
146 | mutex_lock(&vq->mutex); |
147 | vhost_disable_notify(vq); | |
148 | ||
0e255572 | 149 | if (wmem < sock->sk->sk_sndbuf / 2) |
3a4d5c94 | 150 | tx_poll_stop(net); |
8dd014ad | 151 | hdr_size = vq->vhost_hlen; |
3a4d5c94 MT |
152 | |
153 | for (;;) { | |
154 | head = vhost_get_vq_desc(&net->dev, vq, vq->iov, | |
155 | ARRAY_SIZE(vq->iov), | |
156 | &out, &in, | |
157 | NULL, NULL); | |
d5675bd2 | 158 | /* On error, stop handling until the next kick. */ |
7b3384fc | 159 | if (unlikely(head < 0)) |
d5675bd2 | 160 | break; |
3a4d5c94 MT |
161 | /* Nothing new? Wait for eventfd to tell us they refilled. */ |
162 | if (head == vq->num) { | |
163 | wmem = atomic_read(&sock->sk->sk_wmem_alloc); | |
164 | if (wmem >= sock->sk->sk_sndbuf * 3 / 4) { | |
165 | tx_poll_start(net, sock); | |
166 | set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); | |
167 | break; | |
168 | } | |
169 | if (unlikely(vhost_enable_notify(vq))) { | |
170 | vhost_disable_notify(vq); | |
171 | continue; | |
172 | } | |
173 | break; | |
174 | } | |
175 | if (in) { | |
176 | vq_err(vq, "Unexpected descriptor format for TX: " | |
177 | "out %d, int %d\n", out, in); | |
178 | break; | |
179 | } | |
180 | /* Skip header. TODO: support TSO. */ | |
181 | s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, out); | |
182 | msg.msg_iovlen = out; | |
183 | len = iov_length(vq->iov, out); | |
184 | /* Sanity check */ | |
185 | if (!len) { | |
186 | vq_err(vq, "Unexpected header len for TX: " | |
187 | "%zd expected %zd\n", | |
188 | iov_length(vq->hdr, s), hdr_size); | |
189 | break; | |
190 | } | |
191 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ | |
192 | err = sock->ops->sendmsg(NULL, sock, &msg, len); | |
193 | if (unlikely(err < 0)) { | |
8dd014ad | 194 | vhost_discard_vq_desc(vq, 1); |
3a4d5c94 MT |
195 | tx_poll_start(net, sock); |
196 | break; | |
197 | } | |
198 | if (err != len) | |
95c0ec6a MT |
199 | pr_debug("Truncated TX packet: " |
200 | " len %d != %zd\n", err, len); | |
3a4d5c94 MT |
201 | vhost_add_used_and_signal(&net->dev, vq, head, 0); |
202 | total_len += len; | |
203 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
204 | vhost_poll_queue(&vq->poll); | |
205 | break; | |
206 | } | |
207 | } | |
208 | ||
209 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
210 | } |
211 | ||
8dd014ad DS |
212 | static int peek_head_len(struct sock *sk) |
213 | { | |
214 | struct sk_buff *head; | |
215 | int len = 0; | |
216 | ||
217 | lock_sock(sk); | |
218 | head = skb_peek(&sk->sk_receive_queue); | |
219 | if (head) | |
220 | len = head->len; | |
221 | release_sock(sk); | |
222 | return len; | |
223 | } | |
224 | ||
225 | /* This is a multi-buffer version of vhost_get_desc, that works if | |
226 | * vq has read descriptors only. | |
227 | * @vq - the relevant virtqueue | |
228 | * @datalen - data length we'll be reading | |
229 | * @iovcount - returned count of io vectors we fill | |
230 | * @log - vhost log | |
231 | * @log_num - log offset | |
94249369 | 232 | * @quota - headcount quota, 1 for big buffer |
8dd014ad DS |
233 | * returns number of buffer heads allocated, negative on error |
234 | */ | |
235 | static int get_rx_bufs(struct vhost_virtqueue *vq, | |
236 | struct vring_used_elem *heads, | |
237 | int datalen, | |
238 | unsigned *iovcount, | |
239 | struct vhost_log *log, | |
94249369 JW |
240 | unsigned *log_num, |
241 | unsigned int quota) | |
8dd014ad DS |
242 | { |
243 | unsigned int out, in; | |
244 | int seg = 0; | |
245 | int headcount = 0; | |
246 | unsigned d; | |
247 | int r, nlogs = 0; | |
248 | ||
94249369 | 249 | while (datalen > 0 && headcount < quota) { |
e0e9b406 | 250 | if (unlikely(seg >= UIO_MAXIOV)) { |
8dd014ad DS |
251 | r = -ENOBUFS; |
252 | goto err; | |
253 | } | |
254 | d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, | |
255 | ARRAY_SIZE(vq->iov) - seg, &out, | |
256 | &in, log, log_num); | |
257 | if (d == vq->num) { | |
258 | r = 0; | |
259 | goto err; | |
260 | } | |
261 | if (unlikely(out || in <= 0)) { | |
262 | vq_err(vq, "unexpected descriptor format for RX: " | |
263 | "out %d, in %d\n", out, in); | |
264 | r = -EINVAL; | |
265 | goto err; | |
266 | } | |
267 | if (unlikely(log)) { | |
268 | nlogs += *log_num; | |
269 | log += *log_num; | |
270 | } | |
271 | heads[headcount].id = d; | |
272 | heads[headcount].len = iov_length(vq->iov + seg, in); | |
273 | datalen -= heads[headcount].len; | |
274 | ++headcount; | |
275 | seg += in; | |
276 | } | |
277 | heads[headcount - 1].len += datalen; | |
278 | *iovcount = seg; | |
279 | if (unlikely(log)) | |
280 | *log_num = nlogs; | |
281 | return headcount; | |
282 | err: | |
283 | vhost_discard_vq_desc(vq, headcount); | |
284 | return r; | |
285 | } | |
286 | ||
3a4d5c94 MT |
287 | /* Expects to be always run from workqueue - which acts as |
288 | * read-size critical section for our kind of RCU. */ | |
94249369 | 289 | static void handle_rx(struct vhost_net *net) |
3a4d5c94 | 290 | { |
8dd014ad DS |
291 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX]; |
292 | unsigned uninitialized_var(in), log; | |
293 | struct vhost_log *vq_log; | |
294 | struct msghdr msg = { | |
295 | .msg_name = NULL, | |
296 | .msg_namelen = 0, | |
297 | .msg_control = NULL, /* FIXME: get and handle RX aux data. */ | |
298 | .msg_controllen = 0, | |
299 | .msg_iov = vq->iov, | |
300 | .msg_flags = MSG_DONTWAIT, | |
301 | }; | |
8dd014ad DS |
302 | struct virtio_net_hdr_mrg_rxbuf hdr = { |
303 | .hdr.flags = 0, | |
304 | .hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE | |
305 | }; | |
8dd014ad | 306 | size_t total_len = 0; |
cfbdab95 | 307 | int err, headcount, mergeable; |
8dd014ad DS |
308 | size_t vhost_hlen, sock_hlen; |
309 | size_t vhost_len, sock_len; | |
5e18247b MT |
310 | /* TODO: check that we are running from vhost_worker? */ |
311 | struct socket *sock = rcu_dereference_check(vq->private_data, 1); | |
d47effe1 | 312 | |
8dd014ad DS |
313 | if (!sock || skb_queue_empty(&sock->sk->sk_receive_queue)) |
314 | return; | |
315 | ||
8dd014ad DS |
316 | mutex_lock(&vq->mutex); |
317 | vhost_disable_notify(vq); | |
318 | vhost_hlen = vq->vhost_hlen; | |
319 | sock_hlen = vq->sock_hlen; | |
320 | ||
321 | vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? | |
322 | vq->log : NULL; | |
cfbdab95 | 323 | mergeable = vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF); |
8dd014ad DS |
324 | |
325 | while ((sock_len = peek_head_len(sock->sk))) { | |
326 | sock_len += sock_hlen; | |
327 | vhost_len = sock_len + vhost_hlen; | |
328 | headcount = get_rx_bufs(vq, vq->heads, vhost_len, | |
94249369 JW |
329 | &in, vq_log, &log, |
330 | likely(mergeable) ? UIO_MAXIOV : 1); | |
8dd014ad DS |
331 | /* On error, stop handling until the next kick. */ |
332 | if (unlikely(headcount < 0)) | |
333 | break; | |
334 | /* OK, now we need to know about added descriptors. */ | |
335 | if (!headcount) { | |
336 | if (unlikely(vhost_enable_notify(vq))) { | |
337 | /* They have slipped one in as we were | |
338 | * doing that: check again. */ | |
339 | vhost_disable_notify(vq); | |
340 | continue; | |
341 | } | |
342 | /* Nothing new? Wait for eventfd to tell us | |
343 | * they refilled. */ | |
344 | break; | |
345 | } | |
346 | /* We don't need to be notified again. */ | |
347 | if (unlikely((vhost_hlen))) | |
348 | /* Skip header. TODO: support TSO. */ | |
349 | move_iovec_hdr(vq->iov, vq->hdr, vhost_hlen, in); | |
350 | else | |
351 | /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: | |
a290aec8 | 352 | * needed because recvmsg can modify msg_iov. */ |
8dd014ad DS |
353 | copy_iovec_hdr(vq->iov, vq->hdr, sock_hlen, in); |
354 | msg.msg_iovlen = in; | |
355 | err = sock->ops->recvmsg(NULL, sock, &msg, | |
356 | sock_len, MSG_DONTWAIT | MSG_TRUNC); | |
357 | /* Userspace might have consumed the packet meanwhile: | |
358 | * it's not supposed to do this usually, but might be hard | |
359 | * to prevent. Discard data we got (if any) and keep going. */ | |
360 | if (unlikely(err != sock_len)) { | |
361 | pr_debug("Discarded rx packet: " | |
362 | " len %d, expected %zd\n", err, sock_len); | |
363 | vhost_discard_vq_desc(vq, headcount); | |
364 | continue; | |
365 | } | |
366 | if (unlikely(vhost_hlen) && | |
367 | memcpy_toiovecend(vq->hdr, (unsigned char *)&hdr, 0, | |
368 | vhost_hlen)) { | |
369 | vq_err(vq, "Unable to write vnet_hdr at addr %p\n", | |
370 | vq->iov->iov_base); | |
371 | break; | |
372 | } | |
373 | /* TODO: Should check and handle checksum. */ | |
cfbdab95 | 374 | if (likely(mergeable) && |
8dd014ad DS |
375 | memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount, |
376 | offsetof(typeof(hdr), num_buffers), | |
377 | sizeof hdr.num_buffers)) { | |
378 | vq_err(vq, "Failed num_buffers write"); | |
379 | vhost_discard_vq_desc(vq, headcount); | |
380 | break; | |
381 | } | |
382 | vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, | |
383 | headcount); | |
384 | if (unlikely(vq_log)) | |
385 | vhost_log_write(vq, vq_log, log, vhost_len); | |
386 | total_len += vhost_len; | |
387 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
388 | vhost_poll_queue(&vq->poll); | |
389 | break; | |
390 | } | |
391 | } | |
392 | ||
393 | mutex_unlock(&vq->mutex); | |
8dd014ad DS |
394 | } |
395 | ||
c23f3445 | 396 | static void handle_tx_kick(struct vhost_work *work) |
3a4d5c94 | 397 | { |
c23f3445 TH |
398 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
399 | poll.work); | |
400 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
401 | ||
3a4d5c94 MT |
402 | handle_tx(net); |
403 | } | |
404 | ||
c23f3445 | 405 | static void handle_rx_kick(struct vhost_work *work) |
3a4d5c94 | 406 | { |
c23f3445 TH |
407 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
408 | poll.work); | |
409 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
410 | ||
3a4d5c94 MT |
411 | handle_rx(net); |
412 | } | |
413 | ||
c23f3445 | 414 | static void handle_tx_net(struct vhost_work *work) |
3a4d5c94 | 415 | { |
c23f3445 TH |
416 | struct vhost_net *net = container_of(work, struct vhost_net, |
417 | poll[VHOST_NET_VQ_TX].work); | |
3a4d5c94 MT |
418 | handle_tx(net); |
419 | } | |
420 | ||
c23f3445 | 421 | static void handle_rx_net(struct vhost_work *work) |
3a4d5c94 | 422 | { |
c23f3445 TH |
423 | struct vhost_net *net = container_of(work, struct vhost_net, |
424 | poll[VHOST_NET_VQ_RX].work); | |
3a4d5c94 MT |
425 | handle_rx(net); |
426 | } | |
427 | ||
428 | static int vhost_net_open(struct inode *inode, struct file *f) | |
429 | { | |
430 | struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); | |
c23f3445 | 431 | struct vhost_dev *dev; |
3a4d5c94 | 432 | int r; |
c23f3445 | 433 | |
3a4d5c94 MT |
434 | if (!n) |
435 | return -ENOMEM; | |
c23f3445 TH |
436 | |
437 | dev = &n->dev; | |
3a4d5c94 MT |
438 | n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick; |
439 | n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick; | |
c23f3445 | 440 | r = vhost_dev_init(dev, n->vqs, VHOST_NET_VQ_MAX); |
3a4d5c94 MT |
441 | if (r < 0) { |
442 | kfree(n); | |
443 | return r; | |
444 | } | |
445 | ||
c23f3445 TH |
446 | vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); |
447 | vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); | |
3a4d5c94 MT |
448 | n->tx_poll_state = VHOST_NET_POLL_DISABLED; |
449 | ||
450 | f->private_data = n; | |
451 | ||
452 | return 0; | |
453 | } | |
454 | ||
455 | static void vhost_net_disable_vq(struct vhost_net *n, | |
456 | struct vhost_virtqueue *vq) | |
457 | { | |
458 | if (!vq->private_data) | |
459 | return; | |
460 | if (vq == n->vqs + VHOST_NET_VQ_TX) { | |
461 | tx_poll_stop(n); | |
462 | n->tx_poll_state = VHOST_NET_POLL_DISABLED; | |
463 | } else | |
464 | vhost_poll_stop(n->poll + VHOST_NET_VQ_RX); | |
465 | } | |
466 | ||
467 | static void vhost_net_enable_vq(struct vhost_net *n, | |
468 | struct vhost_virtqueue *vq) | |
469 | { | |
28457ee6 AB |
470 | struct socket *sock; |
471 | ||
472 | sock = rcu_dereference_protected(vq->private_data, | |
473 | lockdep_is_held(&vq->mutex)); | |
3a4d5c94 MT |
474 | if (!sock) |
475 | return; | |
476 | if (vq == n->vqs + VHOST_NET_VQ_TX) { | |
477 | n->tx_poll_state = VHOST_NET_POLL_STOPPED; | |
478 | tx_poll_start(n, sock); | |
479 | } else | |
480 | vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file); | |
481 | } | |
482 | ||
483 | static struct socket *vhost_net_stop_vq(struct vhost_net *n, | |
484 | struct vhost_virtqueue *vq) | |
485 | { | |
486 | struct socket *sock; | |
487 | ||
488 | mutex_lock(&vq->mutex); | |
28457ee6 AB |
489 | sock = rcu_dereference_protected(vq->private_data, |
490 | lockdep_is_held(&vq->mutex)); | |
3a4d5c94 MT |
491 | vhost_net_disable_vq(n, vq); |
492 | rcu_assign_pointer(vq->private_data, NULL); | |
493 | mutex_unlock(&vq->mutex); | |
494 | return sock; | |
495 | } | |
496 | ||
497 | static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, | |
498 | struct socket **rx_sock) | |
499 | { | |
500 | *tx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_TX); | |
501 | *rx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_RX); | |
502 | } | |
503 | ||
504 | static void vhost_net_flush_vq(struct vhost_net *n, int index) | |
505 | { | |
506 | vhost_poll_flush(n->poll + index); | |
507 | vhost_poll_flush(&n->dev.vqs[index].poll); | |
508 | } | |
509 | ||
510 | static void vhost_net_flush(struct vhost_net *n) | |
511 | { | |
512 | vhost_net_flush_vq(n, VHOST_NET_VQ_TX); | |
513 | vhost_net_flush_vq(n, VHOST_NET_VQ_RX); | |
514 | } | |
515 | ||
516 | static int vhost_net_release(struct inode *inode, struct file *f) | |
517 | { | |
518 | struct vhost_net *n = f->private_data; | |
519 | struct socket *tx_sock; | |
520 | struct socket *rx_sock; | |
521 | ||
522 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
523 | vhost_net_flush(n); | |
524 | vhost_dev_cleanup(&n->dev); | |
525 | if (tx_sock) | |
526 | fput(tx_sock->file); | |
527 | if (rx_sock) | |
528 | fput(rx_sock->file); | |
529 | /* We do an extra flush before freeing memory, | |
530 | * since jobs can re-queue themselves. */ | |
531 | vhost_net_flush(n); | |
532 | kfree(n); | |
533 | return 0; | |
534 | } | |
535 | ||
536 | static struct socket *get_raw_socket(int fd) | |
537 | { | |
538 | struct { | |
539 | struct sockaddr_ll sa; | |
540 | char buf[MAX_ADDR_LEN]; | |
541 | } uaddr; | |
542 | int uaddr_len = sizeof uaddr, r; | |
543 | struct socket *sock = sockfd_lookup(fd, &r); | |
d47effe1 | 544 | |
3a4d5c94 MT |
545 | if (!sock) |
546 | return ERR_PTR(-ENOTSOCK); | |
547 | ||
548 | /* Parameter checking */ | |
549 | if (sock->sk->sk_type != SOCK_RAW) { | |
550 | r = -ESOCKTNOSUPPORT; | |
551 | goto err; | |
552 | } | |
553 | ||
554 | r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, | |
555 | &uaddr_len, 0); | |
556 | if (r) | |
557 | goto err; | |
558 | ||
559 | if (uaddr.sa.sll_family != AF_PACKET) { | |
560 | r = -EPFNOSUPPORT; | |
561 | goto err; | |
562 | } | |
563 | return sock; | |
564 | err: | |
565 | fput(sock->file); | |
566 | return ERR_PTR(r); | |
567 | } | |
568 | ||
501c774c | 569 | static struct socket *get_tap_socket(int fd) |
3a4d5c94 MT |
570 | { |
571 | struct file *file = fget(fd); | |
572 | struct socket *sock; | |
d47effe1 | 573 | |
3a4d5c94 MT |
574 | if (!file) |
575 | return ERR_PTR(-EBADF); | |
576 | sock = tun_get_socket(file); | |
501c774c AB |
577 | if (!IS_ERR(sock)) |
578 | return sock; | |
579 | sock = macvtap_get_socket(file); | |
3a4d5c94 MT |
580 | if (IS_ERR(sock)) |
581 | fput(file); | |
582 | return sock; | |
583 | } | |
584 | ||
585 | static struct socket *get_socket(int fd) | |
586 | { | |
587 | struct socket *sock; | |
d47effe1 | 588 | |
3a4d5c94 MT |
589 | /* special case to disable backend */ |
590 | if (fd == -1) | |
591 | return NULL; | |
592 | sock = get_raw_socket(fd); | |
593 | if (!IS_ERR(sock)) | |
594 | return sock; | |
501c774c | 595 | sock = get_tap_socket(fd); |
3a4d5c94 MT |
596 | if (!IS_ERR(sock)) |
597 | return sock; | |
598 | return ERR_PTR(-ENOTSOCK); | |
599 | } | |
600 | ||
601 | static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) | |
602 | { | |
603 | struct socket *sock, *oldsock; | |
604 | struct vhost_virtqueue *vq; | |
605 | int r; | |
606 | ||
607 | mutex_lock(&n->dev.mutex); | |
608 | r = vhost_dev_check_owner(&n->dev); | |
609 | if (r) | |
610 | goto err; | |
611 | ||
612 | if (index >= VHOST_NET_VQ_MAX) { | |
613 | r = -ENOBUFS; | |
614 | goto err; | |
615 | } | |
616 | vq = n->vqs + index; | |
617 | mutex_lock(&vq->mutex); | |
618 | ||
619 | /* Verify that ring has been setup correctly. */ | |
620 | if (!vhost_vq_access_ok(vq)) { | |
621 | r = -EFAULT; | |
1dace8c8 | 622 | goto err_vq; |
3a4d5c94 MT |
623 | } |
624 | sock = get_socket(fd); | |
625 | if (IS_ERR(sock)) { | |
626 | r = PTR_ERR(sock); | |
1dace8c8 | 627 | goto err_vq; |
3a4d5c94 MT |
628 | } |
629 | ||
630 | /* start polling new socket */ | |
28457ee6 AB |
631 | oldsock = rcu_dereference_protected(vq->private_data, |
632 | lockdep_is_held(&vq->mutex)); | |
11fe8839 | 633 | if (sock != oldsock) { |
d47effe1 KK |
634 | vhost_net_disable_vq(n, vq); |
635 | rcu_assign_pointer(vq->private_data, sock); | |
636 | vhost_net_enable_vq(n, vq); | |
dd1f4078 | 637 | } |
3a4d5c94 | 638 | |
1680e906 MT |
639 | mutex_unlock(&vq->mutex); |
640 | ||
3a4d5c94 MT |
641 | if (oldsock) { |
642 | vhost_net_flush_vq(n, index); | |
643 | fput(oldsock->file); | |
644 | } | |
1dace8c8 | 645 | |
1680e906 MT |
646 | mutex_unlock(&n->dev.mutex); |
647 | return 0; | |
648 | ||
1dace8c8 JD |
649 | err_vq: |
650 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
651 | err: |
652 | mutex_unlock(&n->dev.mutex); | |
653 | return r; | |
654 | } | |
655 | ||
656 | static long vhost_net_reset_owner(struct vhost_net *n) | |
657 | { | |
658 | struct socket *tx_sock = NULL; | |
659 | struct socket *rx_sock = NULL; | |
660 | long err; | |
d47effe1 | 661 | |
3a4d5c94 MT |
662 | mutex_lock(&n->dev.mutex); |
663 | err = vhost_dev_check_owner(&n->dev); | |
664 | if (err) | |
665 | goto done; | |
666 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
667 | vhost_net_flush(n); | |
668 | err = vhost_dev_reset_owner(&n->dev); | |
669 | done: | |
670 | mutex_unlock(&n->dev.mutex); | |
671 | if (tx_sock) | |
672 | fput(tx_sock->file); | |
673 | if (rx_sock) | |
674 | fput(rx_sock->file); | |
675 | return err; | |
676 | } | |
677 | ||
678 | static int vhost_net_set_features(struct vhost_net *n, u64 features) | |
679 | { | |
8dd014ad | 680 | size_t vhost_hlen, sock_hlen, hdr_len; |
3a4d5c94 | 681 | int i; |
8dd014ad DS |
682 | |
683 | hdr_len = (features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? | |
684 | sizeof(struct virtio_net_hdr_mrg_rxbuf) : | |
685 | sizeof(struct virtio_net_hdr); | |
686 | if (features & (1 << VHOST_NET_F_VIRTIO_NET_HDR)) { | |
687 | /* vhost provides vnet_hdr */ | |
688 | vhost_hlen = hdr_len; | |
689 | sock_hlen = 0; | |
690 | } else { | |
691 | /* socket provides vnet_hdr */ | |
692 | vhost_hlen = 0; | |
693 | sock_hlen = hdr_len; | |
694 | } | |
3a4d5c94 MT |
695 | mutex_lock(&n->dev.mutex); |
696 | if ((features & (1 << VHOST_F_LOG_ALL)) && | |
697 | !vhost_log_access_ok(&n->dev)) { | |
698 | mutex_unlock(&n->dev.mutex); | |
699 | return -EFAULT; | |
700 | } | |
701 | n->dev.acked_features = features; | |
702 | smp_wmb(); | |
703 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { | |
704 | mutex_lock(&n->vqs[i].mutex); | |
8dd014ad DS |
705 | n->vqs[i].vhost_hlen = vhost_hlen; |
706 | n->vqs[i].sock_hlen = sock_hlen; | |
3a4d5c94 MT |
707 | mutex_unlock(&n->vqs[i].mutex); |
708 | } | |
709 | vhost_net_flush(n); | |
710 | mutex_unlock(&n->dev.mutex); | |
711 | return 0; | |
712 | } | |
713 | ||
714 | static long vhost_net_ioctl(struct file *f, unsigned int ioctl, | |
715 | unsigned long arg) | |
716 | { | |
717 | struct vhost_net *n = f->private_data; | |
718 | void __user *argp = (void __user *)arg; | |
719 | u64 __user *featurep = argp; | |
720 | struct vhost_vring_file backend; | |
721 | u64 features; | |
722 | int r; | |
d47effe1 | 723 | |
3a4d5c94 MT |
724 | switch (ioctl) { |
725 | case VHOST_NET_SET_BACKEND: | |
d3553a52 TY |
726 | if (copy_from_user(&backend, argp, sizeof backend)) |
727 | return -EFAULT; | |
3a4d5c94 MT |
728 | return vhost_net_set_backend(n, backend.index, backend.fd); |
729 | case VHOST_GET_FEATURES: | |
730 | features = VHOST_FEATURES; | |
d3553a52 TY |
731 | if (copy_to_user(featurep, &features, sizeof features)) |
732 | return -EFAULT; | |
733 | return 0; | |
3a4d5c94 | 734 | case VHOST_SET_FEATURES: |
d3553a52 TY |
735 | if (copy_from_user(&features, featurep, sizeof features)) |
736 | return -EFAULT; | |
3a4d5c94 MT |
737 | if (features & ~VHOST_FEATURES) |
738 | return -EOPNOTSUPP; | |
739 | return vhost_net_set_features(n, features); | |
740 | case VHOST_RESET_OWNER: | |
741 | return vhost_net_reset_owner(n); | |
742 | default: | |
743 | mutex_lock(&n->dev.mutex); | |
744 | r = vhost_dev_ioctl(&n->dev, ioctl, arg); | |
745 | vhost_net_flush(n); | |
746 | mutex_unlock(&n->dev.mutex); | |
747 | return r; | |
748 | } | |
749 | } | |
750 | ||
751 | #ifdef CONFIG_COMPAT | |
752 | static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, | |
753 | unsigned long arg) | |
754 | { | |
755 | return vhost_net_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); | |
756 | } | |
757 | #endif | |
758 | ||
373a83a6 | 759 | static const struct file_operations vhost_net_fops = { |
3a4d5c94 MT |
760 | .owner = THIS_MODULE, |
761 | .release = vhost_net_release, | |
762 | .unlocked_ioctl = vhost_net_ioctl, | |
763 | #ifdef CONFIG_COMPAT | |
764 | .compat_ioctl = vhost_net_compat_ioctl, | |
765 | #endif | |
766 | .open = vhost_net_open, | |
6038f373 | 767 | .llseek = noop_llseek, |
3a4d5c94 MT |
768 | }; |
769 | ||
770 | static struct miscdevice vhost_net_misc = { | |
79907d89 | 771 | MISC_DYNAMIC_MINOR, |
3a4d5c94 MT |
772 | "vhost-net", |
773 | &vhost_net_fops, | |
774 | }; | |
775 | ||
a8d3782f | 776 | static int vhost_net_init(void) |
3a4d5c94 | 777 | { |
c23f3445 | 778 | return misc_register(&vhost_net_misc); |
3a4d5c94 MT |
779 | } |
780 | module_init(vhost_net_init); | |
781 | ||
a8d3782f | 782 | static void vhost_net_exit(void) |
3a4d5c94 MT |
783 | { |
784 | misc_deregister(&vhost_net_misc); | |
3a4d5c94 MT |
785 | } |
786 | module_exit(vhost_net_exit); | |
787 | ||
788 | MODULE_VERSION("0.0.1"); | |
789 | MODULE_LICENSE("GPL v2"); | |
790 | MODULE_AUTHOR("Michael S. Tsirkin"); | |
791 | MODULE_DESCRIPTION("Host kernel accelerator for virtio net"); |