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> | |
bab632d6 | 15 | #include <linux/moduleparam.h> |
3a4d5c94 MT |
16 | #include <linux/mutex.h> |
17 | #include <linux/workqueue.h> | |
18 | #include <linux/rcupdate.h> | |
19 | #include <linux/file.h> | |
5a0e3ad6 | 20 | #include <linux/slab.h> |
3a4d5c94 MT |
21 | |
22 | #include <linux/net.h> | |
23 | #include <linux/if_packet.h> | |
24 | #include <linux/if_arp.h> | |
25 | #include <linux/if_tun.h> | |
501c774c | 26 | #include <linux/if_macvlan.h> |
3a4d5c94 MT |
27 | |
28 | #include <net/sock.h> | |
29 | ||
30 | #include "vhost.h" | |
31 | ||
bab632d6 MT |
32 | static int experimental_zcopytx; |
33 | module_param(experimental_zcopytx, int, 0444); | |
34 | MODULE_PARM_DESC(experimental_zcopytx, "Enable Experimental Zero Copy TX"); | |
35 | ||
3a4d5c94 MT |
36 | /* Max number of bytes transferred before requeueing the job. |
37 | * Using this limit prevents one virtqueue from starving others. */ | |
38 | #define VHOST_NET_WEIGHT 0x80000 | |
39 | ||
bab632d6 MT |
40 | /* MAX number of TX used buffers for outstanding zerocopy */ |
41 | #define VHOST_MAX_PEND 128 | |
42 | #define VHOST_GOODCOPY_LEN 256 | |
43 | ||
3a4d5c94 MT |
44 | enum { |
45 | VHOST_NET_VQ_RX = 0, | |
46 | VHOST_NET_VQ_TX = 1, | |
47 | VHOST_NET_VQ_MAX = 2, | |
48 | }; | |
49 | ||
50 | enum vhost_net_poll_state { | |
51 | VHOST_NET_POLL_DISABLED = 0, | |
52 | VHOST_NET_POLL_STARTED = 1, | |
53 | VHOST_NET_POLL_STOPPED = 2, | |
54 | }; | |
55 | ||
56 | struct vhost_net { | |
57 | struct vhost_dev dev; | |
58 | struct vhost_virtqueue vqs[VHOST_NET_VQ_MAX]; | |
59 | struct vhost_poll poll[VHOST_NET_VQ_MAX]; | |
60 | /* Tells us whether we are polling a socket for TX. | |
61 | * We only do this when socket buffer fills up. | |
62 | * Protected by tx vq lock. */ | |
63 | enum vhost_net_poll_state tx_poll_state; | |
64 | }; | |
65 | ||
bab632d6 MT |
66 | static bool vhost_sock_zcopy(struct socket *sock) |
67 | { | |
68 | return unlikely(experimental_zcopytx) && | |
69 | sock_flag(sock->sk, SOCK_ZEROCOPY); | |
70 | } | |
71 | ||
3a4d5c94 MT |
72 | /* Pop first len bytes from iovec. Return number of segments used. */ |
73 | static int move_iovec_hdr(struct iovec *from, struct iovec *to, | |
74 | size_t len, int iov_count) | |
75 | { | |
76 | int seg = 0; | |
77 | size_t size; | |
d47effe1 | 78 | |
3a4d5c94 MT |
79 | while (len && seg < iov_count) { |
80 | size = min(from->iov_len, len); | |
81 | to->iov_base = from->iov_base; | |
82 | to->iov_len = size; | |
83 | from->iov_len -= size; | |
84 | from->iov_base += size; | |
85 | len -= size; | |
86 | ++from; | |
87 | ++to; | |
88 | ++seg; | |
89 | } | |
90 | return seg; | |
91 | } | |
8dd014ad DS |
92 | /* Copy iovec entries for len bytes from iovec. */ |
93 | static void copy_iovec_hdr(const struct iovec *from, struct iovec *to, | |
94 | size_t len, int iovcount) | |
95 | { | |
96 | int seg = 0; | |
97 | size_t size; | |
d47effe1 | 98 | |
8dd014ad DS |
99 | while (len && seg < iovcount) { |
100 | size = min(from->iov_len, len); | |
101 | to->iov_base = from->iov_base; | |
102 | to->iov_len = size; | |
103 | len -= size; | |
104 | ++from; | |
105 | ++to; | |
106 | ++seg; | |
107 | } | |
108 | } | |
3a4d5c94 MT |
109 | |
110 | /* Caller must have TX VQ lock */ | |
111 | static void tx_poll_stop(struct vhost_net *net) | |
112 | { | |
113 | if (likely(net->tx_poll_state != VHOST_NET_POLL_STARTED)) | |
114 | return; | |
115 | vhost_poll_stop(net->poll + VHOST_NET_VQ_TX); | |
116 | net->tx_poll_state = VHOST_NET_POLL_STOPPED; | |
117 | } | |
118 | ||
119 | /* Caller must have TX VQ lock */ | |
120 | static void tx_poll_start(struct vhost_net *net, struct socket *sock) | |
121 | { | |
122 | if (unlikely(net->tx_poll_state != VHOST_NET_POLL_STOPPED)) | |
123 | return; | |
124 | vhost_poll_start(net->poll + VHOST_NET_VQ_TX, sock->file); | |
125 | net->tx_poll_state = VHOST_NET_POLL_STARTED; | |
126 | } | |
127 | ||
128 | /* Expects to be always run from workqueue - which acts as | |
129 | * read-size critical section for our kind of RCU. */ | |
130 | static void handle_tx(struct vhost_net *net) | |
131 | { | |
132 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX]; | |
d5675bd2 MT |
133 | unsigned out, in, s; |
134 | int head; | |
3a4d5c94 MT |
135 | struct msghdr msg = { |
136 | .msg_name = NULL, | |
137 | .msg_namelen = 0, | |
138 | .msg_control = NULL, | |
139 | .msg_controllen = 0, | |
140 | .msg_iov = vq->iov, | |
141 | .msg_flags = MSG_DONTWAIT, | |
142 | }; | |
143 | size_t len, total_len = 0; | |
144 | int err, wmem; | |
145 | size_t hdr_size; | |
28457ee6 | 146 | struct socket *sock; |
bab632d6 MT |
147 | struct vhost_ubuf_ref *uninitialized_var(ubufs); |
148 | bool zcopy; | |
28457ee6 | 149 | |
5e18247b | 150 | /* TODO: check that we are running from vhost_worker? */ |
11cd1a8b | 151 | sock = rcu_dereference_check(vq->private_data, 1); |
3a4d5c94 MT |
152 | if (!sock) |
153 | return; | |
154 | ||
155 | wmem = atomic_read(&sock->sk->sk_wmem_alloc); | |
39286fa4 SS |
156 | if (wmem >= sock->sk->sk_sndbuf) { |
157 | mutex_lock(&vq->mutex); | |
158 | tx_poll_start(net, sock); | |
159 | mutex_unlock(&vq->mutex); | |
3a4d5c94 | 160 | return; |
39286fa4 | 161 | } |
3a4d5c94 | 162 | |
3a4d5c94 | 163 | mutex_lock(&vq->mutex); |
8ea8cf89 | 164 | vhost_disable_notify(&net->dev, vq); |
3a4d5c94 | 165 | |
0e255572 | 166 | if (wmem < sock->sk->sk_sndbuf / 2) |
3a4d5c94 | 167 | tx_poll_stop(net); |
8dd014ad | 168 | hdr_size = vq->vhost_hlen; |
bab632d6 | 169 | zcopy = vhost_sock_zcopy(sock); |
3a4d5c94 MT |
170 | |
171 | for (;;) { | |
bab632d6 MT |
172 | /* Release DMAs done buffers first */ |
173 | if (zcopy) | |
174 | vhost_zerocopy_signal_used(vq); | |
175 | ||
3a4d5c94 MT |
176 | head = vhost_get_vq_desc(&net->dev, vq, vq->iov, |
177 | ARRAY_SIZE(vq->iov), | |
178 | &out, &in, | |
179 | NULL, NULL); | |
d5675bd2 | 180 | /* On error, stop handling until the next kick. */ |
7b3384fc | 181 | if (unlikely(head < 0)) |
d5675bd2 | 182 | break; |
3a4d5c94 MT |
183 | /* Nothing new? Wait for eventfd to tell us they refilled. */ |
184 | if (head == vq->num) { | |
185 | wmem = atomic_read(&sock->sk->sk_wmem_alloc); | |
186 | if (wmem >= sock->sk->sk_sndbuf * 3 / 4) { | |
187 | tx_poll_start(net, sock); | |
188 | set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); | |
189 | break; | |
190 | } | |
bab632d6 MT |
191 | /* If more outstanding DMAs, queue the work */ |
192 | if (unlikely(vq->upend_idx - vq->done_idx > | |
193 | VHOST_MAX_PEND)) { | |
194 | tx_poll_start(net, sock); | |
195 | set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); | |
196 | break; | |
197 | } | |
8ea8cf89 MT |
198 | if (unlikely(vhost_enable_notify(&net->dev, vq))) { |
199 | vhost_disable_notify(&net->dev, vq); | |
3a4d5c94 MT |
200 | continue; |
201 | } | |
202 | break; | |
203 | } | |
204 | if (in) { | |
205 | vq_err(vq, "Unexpected descriptor format for TX: " | |
206 | "out %d, int %d\n", out, in); | |
207 | break; | |
208 | } | |
209 | /* Skip header. TODO: support TSO. */ | |
210 | s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, out); | |
211 | msg.msg_iovlen = out; | |
212 | len = iov_length(vq->iov, out); | |
213 | /* Sanity check */ | |
214 | if (!len) { | |
215 | vq_err(vq, "Unexpected header len for TX: " | |
216 | "%zd expected %zd\n", | |
217 | iov_length(vq->hdr, s), hdr_size); | |
218 | break; | |
219 | } | |
bab632d6 MT |
220 | /* use msg_control to pass vhost zerocopy ubuf info to skb */ |
221 | if (zcopy) { | |
222 | vq->heads[vq->upend_idx].id = head; | |
223 | if (len < VHOST_GOODCOPY_LEN) { | |
224 | /* copy don't need to wait for DMA done */ | |
225 | vq->heads[vq->upend_idx].len = | |
226 | VHOST_DMA_DONE_LEN; | |
227 | msg.msg_control = NULL; | |
228 | msg.msg_controllen = 0; | |
229 | ubufs = NULL; | |
230 | } else { | |
231 | struct ubuf_info *ubuf = &vq->ubuf_info[head]; | |
232 | ||
233 | vq->heads[vq->upend_idx].len = len; | |
234 | ubuf->callback = vhost_zerocopy_callback; | |
235 | ubuf->arg = vq->ubufs; | |
236 | ubuf->desc = vq->upend_idx; | |
237 | msg.msg_control = ubuf; | |
238 | msg.msg_controllen = sizeof(ubuf); | |
239 | ubufs = vq->ubufs; | |
240 | kref_get(&ubufs->kref); | |
241 | } | |
242 | vq->upend_idx = (vq->upend_idx + 1) % UIO_MAXIOV; | |
243 | } | |
3a4d5c94 MT |
244 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ |
245 | err = sock->ops->sendmsg(NULL, sock, &msg, len); | |
246 | if (unlikely(err < 0)) { | |
bab632d6 MT |
247 | if (zcopy) { |
248 | if (ubufs) | |
249 | vhost_ubuf_put(ubufs); | |
250 | vq->upend_idx = ((unsigned)vq->upend_idx - 1) % | |
251 | UIO_MAXIOV; | |
252 | } | |
8dd014ad | 253 | vhost_discard_vq_desc(vq, 1); |
3a4d5c94 MT |
254 | tx_poll_start(net, sock); |
255 | break; | |
256 | } | |
257 | if (err != len) | |
95c0ec6a MT |
258 | pr_debug("Truncated TX packet: " |
259 | " len %d != %zd\n", err, len); | |
bab632d6 MT |
260 | if (!zcopy) |
261 | vhost_add_used_and_signal(&net->dev, vq, head, 0); | |
3a4d5c94 MT |
262 | total_len += len; |
263 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
264 | vhost_poll_queue(&vq->poll); | |
265 | break; | |
266 | } | |
267 | } | |
268 | ||
269 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
270 | } |
271 | ||
8dd014ad DS |
272 | static int peek_head_len(struct sock *sk) |
273 | { | |
274 | struct sk_buff *head; | |
275 | int len = 0; | |
783e3988 | 276 | unsigned long flags; |
8dd014ad | 277 | |
783e3988 | 278 | spin_lock_irqsave(&sk->sk_receive_queue.lock, flags); |
8dd014ad | 279 | head = skb_peek(&sk->sk_receive_queue); |
783e3988 | 280 | if (likely(head)) |
8dd014ad | 281 | len = head->len; |
783e3988 | 282 | spin_unlock_irqrestore(&sk->sk_receive_queue.lock, flags); |
8dd014ad DS |
283 | return len; |
284 | } | |
285 | ||
286 | /* This is a multi-buffer version of vhost_get_desc, that works if | |
287 | * vq has read descriptors only. | |
288 | * @vq - the relevant virtqueue | |
289 | * @datalen - data length we'll be reading | |
290 | * @iovcount - returned count of io vectors we fill | |
291 | * @log - vhost log | |
292 | * @log_num - log offset | |
94249369 | 293 | * @quota - headcount quota, 1 for big buffer |
8dd014ad DS |
294 | * returns number of buffer heads allocated, negative on error |
295 | */ | |
296 | static int get_rx_bufs(struct vhost_virtqueue *vq, | |
297 | struct vring_used_elem *heads, | |
298 | int datalen, | |
299 | unsigned *iovcount, | |
300 | struct vhost_log *log, | |
94249369 JW |
301 | unsigned *log_num, |
302 | unsigned int quota) | |
8dd014ad DS |
303 | { |
304 | unsigned int out, in; | |
305 | int seg = 0; | |
306 | int headcount = 0; | |
307 | unsigned d; | |
308 | int r, nlogs = 0; | |
309 | ||
94249369 | 310 | while (datalen > 0 && headcount < quota) { |
e0e9b406 | 311 | if (unlikely(seg >= UIO_MAXIOV)) { |
8dd014ad DS |
312 | r = -ENOBUFS; |
313 | goto err; | |
314 | } | |
315 | d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, | |
316 | ARRAY_SIZE(vq->iov) - seg, &out, | |
317 | &in, log, log_num); | |
318 | if (d == vq->num) { | |
319 | r = 0; | |
320 | goto err; | |
321 | } | |
322 | if (unlikely(out || in <= 0)) { | |
323 | vq_err(vq, "unexpected descriptor format for RX: " | |
324 | "out %d, in %d\n", out, in); | |
325 | r = -EINVAL; | |
326 | goto err; | |
327 | } | |
328 | if (unlikely(log)) { | |
329 | nlogs += *log_num; | |
330 | log += *log_num; | |
331 | } | |
332 | heads[headcount].id = d; | |
333 | heads[headcount].len = iov_length(vq->iov + seg, in); | |
334 | datalen -= heads[headcount].len; | |
335 | ++headcount; | |
336 | seg += in; | |
337 | } | |
338 | heads[headcount - 1].len += datalen; | |
339 | *iovcount = seg; | |
340 | if (unlikely(log)) | |
341 | *log_num = nlogs; | |
342 | return headcount; | |
343 | err: | |
344 | vhost_discard_vq_desc(vq, headcount); | |
345 | return r; | |
346 | } | |
347 | ||
3a4d5c94 MT |
348 | /* Expects to be always run from workqueue - which acts as |
349 | * read-size critical section for our kind of RCU. */ | |
94249369 | 350 | static void handle_rx(struct vhost_net *net) |
3a4d5c94 | 351 | { |
8dd014ad DS |
352 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX]; |
353 | unsigned uninitialized_var(in), log; | |
354 | struct vhost_log *vq_log; | |
355 | struct msghdr msg = { | |
356 | .msg_name = NULL, | |
357 | .msg_namelen = 0, | |
358 | .msg_control = NULL, /* FIXME: get and handle RX aux data. */ | |
359 | .msg_controllen = 0, | |
360 | .msg_iov = vq->iov, | |
361 | .msg_flags = MSG_DONTWAIT, | |
362 | }; | |
8dd014ad DS |
363 | struct virtio_net_hdr_mrg_rxbuf hdr = { |
364 | .hdr.flags = 0, | |
365 | .hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE | |
366 | }; | |
8dd014ad | 367 | size_t total_len = 0; |
cfbdab95 | 368 | int err, headcount, mergeable; |
8dd014ad DS |
369 | size_t vhost_hlen, sock_hlen; |
370 | size_t vhost_len, sock_len; | |
5e18247b MT |
371 | /* TODO: check that we are running from vhost_worker? */ |
372 | struct socket *sock = rcu_dereference_check(vq->private_data, 1); | |
d47effe1 | 373 | |
de4d768a | 374 | if (!sock) |
8dd014ad DS |
375 | return; |
376 | ||
8dd014ad | 377 | mutex_lock(&vq->mutex); |
8ea8cf89 | 378 | vhost_disable_notify(&net->dev, vq); |
8dd014ad DS |
379 | vhost_hlen = vq->vhost_hlen; |
380 | sock_hlen = vq->sock_hlen; | |
381 | ||
382 | vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? | |
383 | vq->log : NULL; | |
cfbdab95 | 384 | mergeable = vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF); |
8dd014ad DS |
385 | |
386 | while ((sock_len = peek_head_len(sock->sk))) { | |
387 | sock_len += sock_hlen; | |
388 | vhost_len = sock_len + vhost_hlen; | |
389 | headcount = get_rx_bufs(vq, vq->heads, vhost_len, | |
94249369 JW |
390 | &in, vq_log, &log, |
391 | likely(mergeable) ? UIO_MAXIOV : 1); | |
8dd014ad DS |
392 | /* On error, stop handling until the next kick. */ |
393 | if (unlikely(headcount < 0)) | |
394 | break; | |
395 | /* OK, now we need to know about added descriptors. */ | |
396 | if (!headcount) { | |
8ea8cf89 | 397 | if (unlikely(vhost_enable_notify(&net->dev, vq))) { |
8dd014ad DS |
398 | /* They have slipped one in as we were |
399 | * doing that: check again. */ | |
8ea8cf89 | 400 | vhost_disable_notify(&net->dev, vq); |
8dd014ad DS |
401 | continue; |
402 | } | |
403 | /* Nothing new? Wait for eventfd to tell us | |
404 | * they refilled. */ | |
405 | break; | |
406 | } | |
407 | /* We don't need to be notified again. */ | |
408 | if (unlikely((vhost_hlen))) | |
409 | /* Skip header. TODO: support TSO. */ | |
410 | move_iovec_hdr(vq->iov, vq->hdr, vhost_hlen, in); | |
411 | else | |
412 | /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: | |
a290aec8 | 413 | * needed because recvmsg can modify msg_iov. */ |
8dd014ad DS |
414 | copy_iovec_hdr(vq->iov, vq->hdr, sock_hlen, in); |
415 | msg.msg_iovlen = in; | |
416 | err = sock->ops->recvmsg(NULL, sock, &msg, | |
417 | sock_len, MSG_DONTWAIT | MSG_TRUNC); | |
418 | /* Userspace might have consumed the packet meanwhile: | |
419 | * it's not supposed to do this usually, but might be hard | |
420 | * to prevent. Discard data we got (if any) and keep going. */ | |
421 | if (unlikely(err != sock_len)) { | |
422 | pr_debug("Discarded rx packet: " | |
423 | " len %d, expected %zd\n", err, sock_len); | |
424 | vhost_discard_vq_desc(vq, headcount); | |
425 | continue; | |
426 | } | |
427 | if (unlikely(vhost_hlen) && | |
428 | memcpy_toiovecend(vq->hdr, (unsigned char *)&hdr, 0, | |
429 | vhost_hlen)) { | |
430 | vq_err(vq, "Unable to write vnet_hdr at addr %p\n", | |
431 | vq->iov->iov_base); | |
432 | break; | |
433 | } | |
434 | /* TODO: Should check and handle checksum. */ | |
cfbdab95 | 435 | if (likely(mergeable) && |
8dd014ad DS |
436 | memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount, |
437 | offsetof(typeof(hdr), num_buffers), | |
438 | sizeof hdr.num_buffers)) { | |
439 | vq_err(vq, "Failed num_buffers write"); | |
440 | vhost_discard_vq_desc(vq, headcount); | |
441 | break; | |
442 | } | |
443 | vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, | |
444 | headcount); | |
445 | if (unlikely(vq_log)) | |
446 | vhost_log_write(vq, vq_log, log, vhost_len); | |
447 | total_len += vhost_len; | |
448 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
449 | vhost_poll_queue(&vq->poll); | |
450 | break; | |
451 | } | |
452 | } | |
453 | ||
454 | mutex_unlock(&vq->mutex); | |
8dd014ad DS |
455 | } |
456 | ||
c23f3445 | 457 | static void handle_tx_kick(struct vhost_work *work) |
3a4d5c94 | 458 | { |
c23f3445 TH |
459 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
460 | poll.work); | |
461 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
462 | ||
3a4d5c94 MT |
463 | handle_tx(net); |
464 | } | |
465 | ||
c23f3445 | 466 | static void handle_rx_kick(struct vhost_work *work) |
3a4d5c94 | 467 | { |
c23f3445 TH |
468 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
469 | poll.work); | |
470 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
471 | ||
3a4d5c94 MT |
472 | handle_rx(net); |
473 | } | |
474 | ||
c23f3445 | 475 | static void handle_tx_net(struct vhost_work *work) |
3a4d5c94 | 476 | { |
c23f3445 TH |
477 | struct vhost_net *net = container_of(work, struct vhost_net, |
478 | poll[VHOST_NET_VQ_TX].work); | |
3a4d5c94 MT |
479 | handle_tx(net); |
480 | } | |
481 | ||
c23f3445 | 482 | static void handle_rx_net(struct vhost_work *work) |
3a4d5c94 | 483 | { |
c23f3445 TH |
484 | struct vhost_net *net = container_of(work, struct vhost_net, |
485 | poll[VHOST_NET_VQ_RX].work); | |
3a4d5c94 MT |
486 | handle_rx(net); |
487 | } | |
488 | ||
489 | static int vhost_net_open(struct inode *inode, struct file *f) | |
490 | { | |
491 | struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); | |
c23f3445 | 492 | struct vhost_dev *dev; |
3a4d5c94 | 493 | int r; |
c23f3445 | 494 | |
3a4d5c94 MT |
495 | if (!n) |
496 | return -ENOMEM; | |
c23f3445 TH |
497 | |
498 | dev = &n->dev; | |
3a4d5c94 MT |
499 | n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick; |
500 | n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick; | |
c23f3445 | 501 | r = vhost_dev_init(dev, n->vqs, VHOST_NET_VQ_MAX); |
3a4d5c94 MT |
502 | if (r < 0) { |
503 | kfree(n); | |
504 | return r; | |
505 | } | |
506 | ||
c23f3445 TH |
507 | vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); |
508 | vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); | |
3a4d5c94 MT |
509 | n->tx_poll_state = VHOST_NET_POLL_DISABLED; |
510 | ||
511 | f->private_data = n; | |
512 | ||
513 | return 0; | |
514 | } | |
515 | ||
516 | static void vhost_net_disable_vq(struct vhost_net *n, | |
517 | struct vhost_virtqueue *vq) | |
518 | { | |
519 | if (!vq->private_data) | |
520 | return; | |
521 | if (vq == n->vqs + VHOST_NET_VQ_TX) { | |
522 | tx_poll_stop(n); | |
523 | n->tx_poll_state = VHOST_NET_POLL_DISABLED; | |
524 | } else | |
525 | vhost_poll_stop(n->poll + VHOST_NET_VQ_RX); | |
526 | } | |
527 | ||
528 | static void vhost_net_enable_vq(struct vhost_net *n, | |
529 | struct vhost_virtqueue *vq) | |
530 | { | |
28457ee6 AB |
531 | struct socket *sock; |
532 | ||
533 | sock = rcu_dereference_protected(vq->private_data, | |
534 | lockdep_is_held(&vq->mutex)); | |
3a4d5c94 MT |
535 | if (!sock) |
536 | return; | |
537 | if (vq == n->vqs + VHOST_NET_VQ_TX) { | |
538 | n->tx_poll_state = VHOST_NET_POLL_STOPPED; | |
539 | tx_poll_start(n, sock); | |
540 | } else | |
541 | vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file); | |
542 | } | |
543 | ||
544 | static struct socket *vhost_net_stop_vq(struct vhost_net *n, | |
545 | struct vhost_virtqueue *vq) | |
546 | { | |
547 | struct socket *sock; | |
548 | ||
549 | mutex_lock(&vq->mutex); | |
28457ee6 AB |
550 | sock = rcu_dereference_protected(vq->private_data, |
551 | lockdep_is_held(&vq->mutex)); | |
3a4d5c94 MT |
552 | vhost_net_disable_vq(n, vq); |
553 | rcu_assign_pointer(vq->private_data, NULL); | |
554 | mutex_unlock(&vq->mutex); | |
555 | return sock; | |
556 | } | |
557 | ||
558 | static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, | |
559 | struct socket **rx_sock) | |
560 | { | |
561 | *tx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_TX); | |
562 | *rx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_RX); | |
563 | } | |
564 | ||
565 | static void vhost_net_flush_vq(struct vhost_net *n, int index) | |
566 | { | |
567 | vhost_poll_flush(n->poll + index); | |
568 | vhost_poll_flush(&n->dev.vqs[index].poll); | |
569 | } | |
570 | ||
571 | static void vhost_net_flush(struct vhost_net *n) | |
572 | { | |
573 | vhost_net_flush_vq(n, VHOST_NET_VQ_TX); | |
574 | vhost_net_flush_vq(n, VHOST_NET_VQ_RX); | |
575 | } | |
576 | ||
577 | static int vhost_net_release(struct inode *inode, struct file *f) | |
578 | { | |
579 | struct vhost_net *n = f->private_data; | |
580 | struct socket *tx_sock; | |
581 | struct socket *rx_sock; | |
582 | ||
583 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
584 | vhost_net_flush(n); | |
585 | vhost_dev_cleanup(&n->dev); | |
586 | if (tx_sock) | |
587 | fput(tx_sock->file); | |
588 | if (rx_sock) | |
589 | fput(rx_sock->file); | |
590 | /* We do an extra flush before freeing memory, | |
591 | * since jobs can re-queue themselves. */ | |
592 | vhost_net_flush(n); | |
593 | kfree(n); | |
594 | return 0; | |
595 | } | |
596 | ||
597 | static struct socket *get_raw_socket(int fd) | |
598 | { | |
599 | struct { | |
600 | struct sockaddr_ll sa; | |
601 | char buf[MAX_ADDR_LEN]; | |
602 | } uaddr; | |
603 | int uaddr_len = sizeof uaddr, r; | |
604 | struct socket *sock = sockfd_lookup(fd, &r); | |
d47effe1 | 605 | |
3a4d5c94 MT |
606 | if (!sock) |
607 | return ERR_PTR(-ENOTSOCK); | |
608 | ||
609 | /* Parameter checking */ | |
610 | if (sock->sk->sk_type != SOCK_RAW) { | |
611 | r = -ESOCKTNOSUPPORT; | |
612 | goto err; | |
613 | } | |
614 | ||
615 | r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, | |
616 | &uaddr_len, 0); | |
617 | if (r) | |
618 | goto err; | |
619 | ||
620 | if (uaddr.sa.sll_family != AF_PACKET) { | |
621 | r = -EPFNOSUPPORT; | |
622 | goto err; | |
623 | } | |
624 | return sock; | |
625 | err: | |
626 | fput(sock->file); | |
627 | return ERR_PTR(r); | |
628 | } | |
629 | ||
501c774c | 630 | static struct socket *get_tap_socket(int fd) |
3a4d5c94 MT |
631 | { |
632 | struct file *file = fget(fd); | |
633 | struct socket *sock; | |
d47effe1 | 634 | |
3a4d5c94 MT |
635 | if (!file) |
636 | return ERR_PTR(-EBADF); | |
637 | sock = tun_get_socket(file); | |
501c774c AB |
638 | if (!IS_ERR(sock)) |
639 | return sock; | |
640 | sock = macvtap_get_socket(file); | |
3a4d5c94 MT |
641 | if (IS_ERR(sock)) |
642 | fput(file); | |
643 | return sock; | |
644 | } | |
645 | ||
646 | static struct socket *get_socket(int fd) | |
647 | { | |
648 | struct socket *sock; | |
d47effe1 | 649 | |
3a4d5c94 MT |
650 | /* special case to disable backend */ |
651 | if (fd == -1) | |
652 | return NULL; | |
653 | sock = get_raw_socket(fd); | |
654 | if (!IS_ERR(sock)) | |
655 | return sock; | |
501c774c | 656 | sock = get_tap_socket(fd); |
3a4d5c94 MT |
657 | if (!IS_ERR(sock)) |
658 | return sock; | |
659 | return ERR_PTR(-ENOTSOCK); | |
660 | } | |
661 | ||
662 | static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) | |
663 | { | |
664 | struct socket *sock, *oldsock; | |
665 | struct vhost_virtqueue *vq; | |
bab632d6 | 666 | struct vhost_ubuf_ref *ubufs, *oldubufs = NULL; |
3a4d5c94 MT |
667 | int r; |
668 | ||
669 | mutex_lock(&n->dev.mutex); | |
670 | r = vhost_dev_check_owner(&n->dev); | |
671 | if (r) | |
672 | goto err; | |
673 | ||
674 | if (index >= VHOST_NET_VQ_MAX) { | |
675 | r = -ENOBUFS; | |
676 | goto err; | |
677 | } | |
678 | vq = n->vqs + index; | |
679 | mutex_lock(&vq->mutex); | |
680 | ||
681 | /* Verify that ring has been setup correctly. */ | |
682 | if (!vhost_vq_access_ok(vq)) { | |
683 | r = -EFAULT; | |
1dace8c8 | 684 | goto err_vq; |
3a4d5c94 MT |
685 | } |
686 | sock = get_socket(fd); | |
687 | if (IS_ERR(sock)) { | |
688 | r = PTR_ERR(sock); | |
1dace8c8 | 689 | goto err_vq; |
3a4d5c94 MT |
690 | } |
691 | ||
692 | /* start polling new socket */ | |
28457ee6 AB |
693 | oldsock = rcu_dereference_protected(vq->private_data, |
694 | lockdep_is_held(&vq->mutex)); | |
11fe8839 | 695 | if (sock != oldsock) { |
bab632d6 MT |
696 | ubufs = vhost_ubuf_alloc(vq, sock && vhost_sock_zcopy(sock)); |
697 | if (IS_ERR(ubufs)) { | |
698 | r = PTR_ERR(ubufs); | |
699 | goto err_ubufs; | |
700 | } | |
701 | oldubufs = vq->ubufs; | |
702 | vq->ubufs = ubufs; | |
d47effe1 KK |
703 | vhost_net_disable_vq(n, vq); |
704 | rcu_assign_pointer(vq->private_data, sock); | |
705 | vhost_net_enable_vq(n, vq); | |
f59281da JW |
706 | |
707 | r = vhost_init_used(vq); | |
708 | if (r) | |
709 | goto err_vq; | |
dd1f4078 | 710 | } |
3a4d5c94 | 711 | |
1680e906 MT |
712 | mutex_unlock(&vq->mutex); |
713 | ||
c047e5f3 | 714 | if (oldubufs) { |
bab632d6 | 715 | vhost_ubuf_put_and_wait(oldubufs); |
c047e5f3 MT |
716 | mutex_lock(&vq->mutex); |
717 | vhost_zerocopy_signal_used(vq); | |
718 | mutex_unlock(&vq->mutex); | |
719 | } | |
bab632d6 | 720 | |
3a4d5c94 MT |
721 | if (oldsock) { |
722 | vhost_net_flush_vq(n, index); | |
723 | fput(oldsock->file); | |
724 | } | |
1dace8c8 | 725 | |
1680e906 MT |
726 | mutex_unlock(&n->dev.mutex); |
727 | return 0; | |
728 | ||
bab632d6 MT |
729 | err_ubufs: |
730 | fput(sock->file); | |
1dace8c8 JD |
731 | err_vq: |
732 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
733 | err: |
734 | mutex_unlock(&n->dev.mutex); | |
735 | return r; | |
736 | } | |
737 | ||
738 | static long vhost_net_reset_owner(struct vhost_net *n) | |
739 | { | |
740 | struct socket *tx_sock = NULL; | |
741 | struct socket *rx_sock = NULL; | |
742 | long err; | |
d47effe1 | 743 | |
3a4d5c94 MT |
744 | mutex_lock(&n->dev.mutex); |
745 | err = vhost_dev_check_owner(&n->dev); | |
746 | if (err) | |
747 | goto done; | |
748 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
749 | vhost_net_flush(n); | |
750 | err = vhost_dev_reset_owner(&n->dev); | |
751 | done: | |
752 | mutex_unlock(&n->dev.mutex); | |
753 | if (tx_sock) | |
754 | fput(tx_sock->file); | |
755 | if (rx_sock) | |
756 | fput(rx_sock->file); | |
757 | return err; | |
758 | } | |
759 | ||
760 | static int vhost_net_set_features(struct vhost_net *n, u64 features) | |
761 | { | |
8dd014ad | 762 | size_t vhost_hlen, sock_hlen, hdr_len; |
3a4d5c94 | 763 | int i; |
8dd014ad DS |
764 | |
765 | hdr_len = (features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? | |
766 | sizeof(struct virtio_net_hdr_mrg_rxbuf) : | |
767 | sizeof(struct virtio_net_hdr); | |
768 | if (features & (1 << VHOST_NET_F_VIRTIO_NET_HDR)) { | |
769 | /* vhost provides vnet_hdr */ | |
770 | vhost_hlen = hdr_len; | |
771 | sock_hlen = 0; | |
772 | } else { | |
773 | /* socket provides vnet_hdr */ | |
774 | vhost_hlen = 0; | |
775 | sock_hlen = hdr_len; | |
776 | } | |
3a4d5c94 MT |
777 | mutex_lock(&n->dev.mutex); |
778 | if ((features & (1 << VHOST_F_LOG_ALL)) && | |
779 | !vhost_log_access_ok(&n->dev)) { | |
780 | mutex_unlock(&n->dev.mutex); | |
781 | return -EFAULT; | |
782 | } | |
783 | n->dev.acked_features = features; | |
784 | smp_wmb(); | |
785 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { | |
786 | mutex_lock(&n->vqs[i].mutex); | |
8dd014ad DS |
787 | n->vqs[i].vhost_hlen = vhost_hlen; |
788 | n->vqs[i].sock_hlen = sock_hlen; | |
3a4d5c94 MT |
789 | mutex_unlock(&n->vqs[i].mutex); |
790 | } | |
791 | vhost_net_flush(n); | |
792 | mutex_unlock(&n->dev.mutex); | |
793 | return 0; | |
794 | } | |
795 | ||
796 | static long vhost_net_ioctl(struct file *f, unsigned int ioctl, | |
797 | unsigned long arg) | |
798 | { | |
799 | struct vhost_net *n = f->private_data; | |
800 | void __user *argp = (void __user *)arg; | |
801 | u64 __user *featurep = argp; | |
802 | struct vhost_vring_file backend; | |
803 | u64 features; | |
804 | int r; | |
d47effe1 | 805 | |
3a4d5c94 MT |
806 | switch (ioctl) { |
807 | case VHOST_NET_SET_BACKEND: | |
d3553a52 TY |
808 | if (copy_from_user(&backend, argp, sizeof backend)) |
809 | return -EFAULT; | |
3a4d5c94 MT |
810 | return vhost_net_set_backend(n, backend.index, backend.fd); |
811 | case VHOST_GET_FEATURES: | |
812 | features = VHOST_FEATURES; | |
d3553a52 TY |
813 | if (copy_to_user(featurep, &features, sizeof features)) |
814 | return -EFAULT; | |
815 | return 0; | |
3a4d5c94 | 816 | case VHOST_SET_FEATURES: |
d3553a52 TY |
817 | if (copy_from_user(&features, featurep, sizeof features)) |
818 | return -EFAULT; | |
3a4d5c94 MT |
819 | if (features & ~VHOST_FEATURES) |
820 | return -EOPNOTSUPP; | |
821 | return vhost_net_set_features(n, features); | |
822 | case VHOST_RESET_OWNER: | |
823 | return vhost_net_reset_owner(n); | |
824 | default: | |
825 | mutex_lock(&n->dev.mutex); | |
826 | r = vhost_dev_ioctl(&n->dev, ioctl, arg); | |
827 | vhost_net_flush(n); | |
828 | mutex_unlock(&n->dev.mutex); | |
829 | return r; | |
830 | } | |
831 | } | |
832 | ||
833 | #ifdef CONFIG_COMPAT | |
834 | static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, | |
835 | unsigned long arg) | |
836 | { | |
837 | return vhost_net_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); | |
838 | } | |
839 | #endif | |
840 | ||
373a83a6 | 841 | static const struct file_operations vhost_net_fops = { |
3a4d5c94 MT |
842 | .owner = THIS_MODULE, |
843 | .release = vhost_net_release, | |
844 | .unlocked_ioctl = vhost_net_ioctl, | |
845 | #ifdef CONFIG_COMPAT | |
846 | .compat_ioctl = vhost_net_compat_ioctl, | |
847 | #endif | |
848 | .open = vhost_net_open, | |
6038f373 | 849 | .llseek = noop_llseek, |
3a4d5c94 MT |
850 | }; |
851 | ||
852 | static struct miscdevice vhost_net_misc = { | |
79907d89 | 853 | MISC_DYNAMIC_MINOR, |
3a4d5c94 MT |
854 | "vhost-net", |
855 | &vhost_net_fops, | |
856 | }; | |
857 | ||
a8d3782f | 858 | static int vhost_net_init(void) |
3a4d5c94 | 859 | { |
bab632d6 MT |
860 | if (experimental_zcopytx) |
861 | vhost_enable_zcopy(VHOST_NET_VQ_TX); | |
c23f3445 | 862 | return misc_register(&vhost_net_misc); |
3a4d5c94 MT |
863 | } |
864 | module_init(vhost_net_init); | |
865 | ||
a8d3782f | 866 | static void vhost_net_exit(void) |
3a4d5c94 MT |
867 | { |
868 | misc_deregister(&vhost_net_misc); | |
3a4d5c94 MT |
869 | } |
870 | module_exit(vhost_net_exit); | |
871 | ||
872 | MODULE_VERSION("0.0.1"); | |
873 | MODULE_LICENSE("GPL v2"); | |
874 | MODULE_AUTHOR("Michael S. Tsirkin"); | |
875 | MODULE_DESCRIPTION("Host kernel accelerator for virtio net"); |