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> |
c53cff5e | 27 | #include <linux/if_vlan.h> |
3a4d5c94 MT |
28 | |
29 | #include <net/sock.h> | |
30 | ||
31 | #include "vhost.h" | |
32 | ||
f9611c43 | 33 | static int experimental_zcopytx = 1; |
bab632d6 | 34 | module_param(experimental_zcopytx, int, 0444); |
f9611c43 MT |
35 | MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;" |
36 | " 1 -Enable; 0 - Disable"); | |
bab632d6 | 37 | |
3a4d5c94 MT |
38 | /* Max number of bytes transferred before requeueing the job. |
39 | * Using this limit prevents one virtqueue from starving others. */ | |
40 | #define VHOST_NET_WEIGHT 0x80000 | |
41 | ||
bab632d6 MT |
42 | /* MAX number of TX used buffers for outstanding zerocopy */ |
43 | #define VHOST_MAX_PEND 128 | |
44 | #define VHOST_GOODCOPY_LEN 256 | |
45 | ||
eaae8132 MT |
46 | /* |
47 | * For transmit, used buffer len is unused; we override it to track buffer | |
48 | * status internally; used for zerocopy tx only. | |
49 | */ | |
50 | /* Lower device DMA failed */ | |
51 | #define VHOST_DMA_FAILED_LEN 3 | |
52 | /* Lower device DMA done */ | |
53 | #define VHOST_DMA_DONE_LEN 2 | |
54 | /* Lower device DMA in progress */ | |
55 | #define VHOST_DMA_IN_PROGRESS 1 | |
56 | /* Buffer unused */ | |
57 | #define VHOST_DMA_CLEAR_LEN 0 | |
58 | ||
59 | #define VHOST_DMA_IS_DONE(len) ((len) >= VHOST_DMA_DONE_LEN) | |
60 | ||
8570a6e7 AH |
61 | enum { |
62 | VHOST_NET_FEATURES = VHOST_FEATURES | | |
63 | (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | | |
64 | (1ULL << VIRTIO_NET_F_MRG_RXBUF), | |
65 | }; | |
66 | ||
3a4d5c94 MT |
67 | enum { |
68 | VHOST_NET_VQ_RX = 0, | |
69 | VHOST_NET_VQ_TX = 1, | |
70 | VHOST_NET_VQ_MAX = 2, | |
71 | }; | |
72 | ||
fe729a57 | 73 | struct vhost_net_ubuf_ref { |
2839400f AH |
74 | struct kref kref; |
75 | wait_queue_head_t wait; | |
76 | struct vhost_virtqueue *vq; | |
77 | }; | |
78 | ||
3ab2e420 AH |
79 | struct vhost_net_virtqueue { |
80 | struct vhost_virtqueue vq; | |
81f95a55 MT |
81 | /* hdr is used to store the virtio header. |
82 | * Since each iovec has >= 1 byte length, we never need more than | |
83 | * header length entries to store the header. */ | |
84 | struct iovec hdr[sizeof(struct virtio_net_hdr_mrg_rxbuf)]; | |
85 | size_t vhost_hlen; | |
86 | size_t sock_hlen; | |
2839400f AH |
87 | /* vhost zerocopy support fields below: */ |
88 | /* last used idx for outstanding DMA zerocopy buffers */ | |
89 | int upend_idx; | |
90 | /* first used idx for DMA done zerocopy buffers */ | |
91 | int done_idx; | |
92 | /* an array of userspace buffers info */ | |
93 | struct ubuf_info *ubuf_info; | |
94 | /* Reference counting for outstanding ubufs. | |
95 | * Protected by vq mutex. Writers must also take device mutex. */ | |
fe729a57 | 96 | struct vhost_net_ubuf_ref *ubufs; |
3ab2e420 AH |
97 | }; |
98 | ||
3a4d5c94 MT |
99 | struct vhost_net { |
100 | struct vhost_dev dev; | |
3ab2e420 | 101 | struct vhost_net_virtqueue vqs[VHOST_NET_VQ_MAX]; |
3a4d5c94 | 102 | struct vhost_poll poll[VHOST_NET_VQ_MAX]; |
eaae8132 MT |
103 | /* Number of TX recently submitted. |
104 | * Protected by tx vq lock. */ | |
105 | unsigned tx_packets; | |
106 | /* Number of times zerocopy TX recently failed. | |
107 | * Protected by tx vq lock. */ | |
108 | unsigned tx_zcopy_err; | |
1280c27f MT |
109 | /* Flush in progress. Protected by tx vq lock. */ |
110 | bool tx_flush; | |
3a4d5c94 MT |
111 | }; |
112 | ||
fe729a57 | 113 | static unsigned vhost_net_zcopy_mask __read_mostly; |
2839400f | 114 | |
fe729a57 | 115 | static void vhost_net_enable_zcopy(int vq) |
2839400f | 116 | { |
fe729a57 | 117 | vhost_net_zcopy_mask |= 0x1 << vq; |
2839400f AH |
118 | } |
119 | ||
fe729a57 | 120 | static void vhost_net_zerocopy_done_signal(struct kref *kref) |
2839400f | 121 | { |
fe729a57 AH |
122 | struct vhost_net_ubuf_ref *ubufs; |
123 | ||
124 | ubufs = container_of(kref, struct vhost_net_ubuf_ref, kref); | |
2839400f AH |
125 | wake_up(&ubufs->wait); |
126 | } | |
127 | ||
fe729a57 AH |
128 | static struct vhost_net_ubuf_ref * |
129 | vhost_net_ubuf_alloc(struct vhost_virtqueue *vq, bool zcopy) | |
2839400f | 130 | { |
fe729a57 | 131 | struct vhost_net_ubuf_ref *ubufs; |
2839400f AH |
132 | /* No zero copy backend? Nothing to count. */ |
133 | if (!zcopy) | |
134 | return NULL; | |
135 | ubufs = kmalloc(sizeof(*ubufs), GFP_KERNEL); | |
136 | if (!ubufs) | |
137 | return ERR_PTR(-ENOMEM); | |
138 | kref_init(&ubufs->kref); | |
139 | init_waitqueue_head(&ubufs->wait); | |
140 | ubufs->vq = vq; | |
141 | return ubufs; | |
142 | } | |
143 | ||
fe729a57 | 144 | static void vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) |
2839400f | 145 | { |
fe729a57 | 146 | kref_put(&ubufs->kref, vhost_net_zerocopy_done_signal); |
2839400f AH |
147 | } |
148 | ||
fe729a57 | 149 | static void vhost_net_ubuf_put_and_wait(struct vhost_net_ubuf_ref *ubufs) |
2839400f | 150 | { |
fe729a57 | 151 | kref_put(&ubufs->kref, vhost_net_zerocopy_done_signal); |
2839400f | 152 | wait_event(ubufs->wait, !atomic_read(&ubufs->kref.refcount)); |
c38e39c3 MT |
153 | } |
154 | ||
155 | static void vhost_net_ubuf_put_wait_and_free(struct vhost_net_ubuf_ref *ubufs) | |
156 | { | |
157 | vhost_net_ubuf_put_and_wait(ubufs); | |
2839400f AH |
158 | kfree(ubufs); |
159 | } | |
160 | ||
b1ad8496 AH |
161 | static void vhost_net_clear_ubuf_info(struct vhost_net *n) |
162 | { | |
b1ad8496 AH |
163 | int i; |
164 | ||
288cfe78 MT |
165 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { |
166 | kfree(n->vqs[i].ubuf_info); | |
167 | n->vqs[i].ubuf_info = NULL; | |
b1ad8496 AH |
168 | } |
169 | } | |
170 | ||
0a1febf7 | 171 | static int vhost_net_set_ubuf_info(struct vhost_net *n) |
2839400f AH |
172 | { |
173 | bool zcopy; | |
174 | int i; | |
175 | ||
288cfe78 | 176 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { |
fe729a57 | 177 | zcopy = vhost_net_zcopy_mask & (0x1 << i); |
2839400f AH |
178 | if (!zcopy) |
179 | continue; | |
180 | n->vqs[i].ubuf_info = kmalloc(sizeof(*n->vqs[i].ubuf_info) * | |
181 | UIO_MAXIOV, GFP_KERNEL); | |
182 | if (!n->vqs[i].ubuf_info) | |
183 | goto err; | |
184 | } | |
185 | return 0; | |
186 | ||
187 | err: | |
288cfe78 | 188 | vhost_net_clear_ubuf_info(n); |
2839400f AH |
189 | return -ENOMEM; |
190 | } | |
191 | ||
0a1febf7 | 192 | static void vhost_net_vq_reset(struct vhost_net *n) |
2839400f AH |
193 | { |
194 | int i; | |
195 | ||
288cfe78 MT |
196 | vhost_net_clear_ubuf_info(n); |
197 | ||
2839400f AH |
198 | for (i = 0; i < VHOST_NET_VQ_MAX; i++) { |
199 | n->vqs[i].done_idx = 0; | |
200 | n->vqs[i].upend_idx = 0; | |
201 | n->vqs[i].ubufs = NULL; | |
81f95a55 MT |
202 | n->vqs[i].vhost_hlen = 0; |
203 | n->vqs[i].sock_hlen = 0; | |
2839400f AH |
204 | } |
205 | ||
206 | } | |
207 | ||
eaae8132 MT |
208 | static void vhost_net_tx_packet(struct vhost_net *net) |
209 | { | |
210 | ++net->tx_packets; | |
211 | if (net->tx_packets < 1024) | |
212 | return; | |
213 | net->tx_packets = 0; | |
214 | net->tx_zcopy_err = 0; | |
215 | } | |
216 | ||
217 | static void vhost_net_tx_err(struct vhost_net *net) | |
218 | { | |
219 | ++net->tx_zcopy_err; | |
220 | } | |
221 | ||
222 | static bool vhost_net_tx_select_zcopy(struct vhost_net *net) | |
223 | { | |
1280c27f MT |
224 | /* TX flush waits for outstanding DMAs to be done. |
225 | * Don't start new DMAs. | |
226 | */ | |
227 | return !net->tx_flush && | |
228 | net->tx_packets / 64 >= net->tx_zcopy_err; | |
eaae8132 MT |
229 | } |
230 | ||
bab632d6 MT |
231 | static bool vhost_sock_zcopy(struct socket *sock) |
232 | { | |
233 | return unlikely(experimental_zcopytx) && | |
234 | sock_flag(sock->sk, SOCK_ZEROCOPY); | |
235 | } | |
236 | ||
3a4d5c94 MT |
237 | /* Pop first len bytes from iovec. Return number of segments used. */ |
238 | static int move_iovec_hdr(struct iovec *from, struct iovec *to, | |
239 | size_t len, int iov_count) | |
240 | { | |
241 | int seg = 0; | |
242 | size_t size; | |
d47effe1 | 243 | |
3a4d5c94 MT |
244 | while (len && seg < iov_count) { |
245 | size = min(from->iov_len, len); | |
246 | to->iov_base = from->iov_base; | |
247 | to->iov_len = size; | |
248 | from->iov_len -= size; | |
249 | from->iov_base += size; | |
250 | len -= size; | |
251 | ++from; | |
252 | ++to; | |
253 | ++seg; | |
254 | } | |
255 | return seg; | |
256 | } | |
8dd014ad DS |
257 | /* Copy iovec entries for len bytes from iovec. */ |
258 | static void copy_iovec_hdr(const struct iovec *from, struct iovec *to, | |
259 | size_t len, int iovcount) | |
260 | { | |
261 | int seg = 0; | |
262 | size_t size; | |
d47effe1 | 263 | |
8dd014ad DS |
264 | while (len && seg < iovcount) { |
265 | size = min(from->iov_len, len); | |
266 | to->iov_base = from->iov_base; | |
267 | to->iov_len = size; | |
268 | len -= size; | |
269 | ++from; | |
270 | ++to; | |
271 | ++seg; | |
272 | } | |
273 | } | |
3a4d5c94 | 274 | |
b211616d MT |
275 | /* In case of DMA done not in order in lower device driver for some reason. |
276 | * upend_idx is used to track end of used idx, done_idx is used to track head | |
277 | * of used idx. Once lower device DMA done contiguously, we will signal KVM | |
278 | * guest used idx. | |
279 | */ | |
eaae8132 MT |
280 | static int vhost_zerocopy_signal_used(struct vhost_net *net, |
281 | struct vhost_virtqueue *vq) | |
b211616d | 282 | { |
2839400f AH |
283 | struct vhost_net_virtqueue *nvq = |
284 | container_of(vq, struct vhost_net_virtqueue, vq); | |
b211616d MT |
285 | int i; |
286 | int j = 0; | |
287 | ||
2839400f | 288 | for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) { |
eaae8132 MT |
289 | if (vq->heads[i].len == VHOST_DMA_FAILED_LEN) |
290 | vhost_net_tx_err(net); | |
b211616d MT |
291 | if (VHOST_DMA_IS_DONE(vq->heads[i].len)) { |
292 | vq->heads[i].len = VHOST_DMA_CLEAR_LEN; | |
293 | vhost_add_used_and_signal(vq->dev, vq, | |
294 | vq->heads[i].id, 0); | |
295 | ++j; | |
296 | } else | |
297 | break; | |
298 | } | |
299 | if (j) | |
2839400f | 300 | nvq->done_idx = i; |
b211616d MT |
301 | return j; |
302 | } | |
303 | ||
eaae8132 | 304 | static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) |
b211616d | 305 | { |
fe729a57 | 306 | struct vhost_net_ubuf_ref *ubufs = ubuf->ctx; |
b211616d | 307 | struct vhost_virtqueue *vq = ubufs->vq; |
24eb21a1 MT |
308 | int cnt = atomic_read(&ubufs->kref.refcount); |
309 | ||
310 | /* | |
311 | * Trigger polling thread if guest stopped submitting new buffers: | |
312 | * in this case, the refcount after decrement will eventually reach 1 | |
313 | * so here it is 2. | |
314 | * We also trigger polling periodically after each 16 packets | |
315 | * (the value 16 here is more or less arbitrary, it's tuned to trigger | |
316 | * less than 10% of times). | |
317 | */ | |
318 | if (cnt <= 2 || !(cnt % 16)) | |
319 | vhost_poll_queue(&vq->poll); | |
b211616d | 320 | /* set len to mark this desc buffers done DMA */ |
eaae8132 MT |
321 | vq->heads[ubuf->desc].len = success ? |
322 | VHOST_DMA_DONE_LEN : VHOST_DMA_FAILED_LEN; | |
fe729a57 | 323 | vhost_net_ubuf_put(ubufs); |
b211616d MT |
324 | } |
325 | ||
3a4d5c94 MT |
326 | /* Expects to be always run from workqueue - which acts as |
327 | * read-size critical section for our kind of RCU. */ | |
328 | static void handle_tx(struct vhost_net *net) | |
329 | { | |
2839400f | 330 | struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; |
81f95a55 | 331 | struct vhost_virtqueue *vq = &nvq->vq; |
d5675bd2 MT |
332 | unsigned out, in, s; |
333 | int head; | |
3a4d5c94 MT |
334 | struct msghdr msg = { |
335 | .msg_name = NULL, | |
336 | .msg_namelen = 0, | |
337 | .msg_control = NULL, | |
338 | .msg_controllen = 0, | |
339 | .msg_iov = vq->iov, | |
340 | .msg_flags = MSG_DONTWAIT, | |
341 | }; | |
342 | size_t len, total_len = 0; | |
70181d51 | 343 | int err; |
3a4d5c94 | 344 | size_t hdr_size; |
28457ee6 | 345 | struct socket *sock; |
fe729a57 | 346 | struct vhost_net_ubuf_ref *uninitialized_var(ubufs); |
cedb9bdc | 347 | bool zcopy, zcopy_used; |
28457ee6 | 348 | |
5e18247b | 349 | /* TODO: check that we are running from vhost_worker? */ |
11cd1a8b | 350 | sock = rcu_dereference_check(vq->private_data, 1); |
3a4d5c94 MT |
351 | if (!sock) |
352 | return; | |
353 | ||
3a4d5c94 | 354 | mutex_lock(&vq->mutex); |
8ea8cf89 | 355 | vhost_disable_notify(&net->dev, vq); |
3a4d5c94 | 356 | |
81f95a55 | 357 | hdr_size = nvq->vhost_hlen; |
2839400f | 358 | zcopy = nvq->ubufs; |
3a4d5c94 MT |
359 | |
360 | for (;;) { | |
bab632d6 MT |
361 | /* Release DMAs done buffers first */ |
362 | if (zcopy) | |
eaae8132 | 363 | vhost_zerocopy_signal_used(net, vq); |
bab632d6 | 364 | |
3a4d5c94 MT |
365 | head = vhost_get_vq_desc(&net->dev, vq, vq->iov, |
366 | ARRAY_SIZE(vq->iov), | |
367 | &out, &in, | |
368 | NULL, NULL); | |
d5675bd2 | 369 | /* On error, stop handling until the next kick. */ |
7b3384fc | 370 | if (unlikely(head < 0)) |
d5675bd2 | 371 | break; |
3a4d5c94 MT |
372 | /* Nothing new? Wait for eventfd to tell us they refilled. */ |
373 | if (head == vq->num) { | |
9e380825 SM |
374 | int num_pends; |
375 | ||
9e380825 SM |
376 | /* If more outstanding DMAs, queue the work. |
377 | * Handle upend_idx wrap around | |
378 | */ | |
2839400f AH |
379 | num_pends = likely(nvq->upend_idx >= nvq->done_idx) ? |
380 | (nvq->upend_idx - nvq->done_idx) : | |
381 | (nvq->upend_idx + UIO_MAXIOV - | |
382 | nvq->done_idx); | |
70181d51 | 383 | if (unlikely(num_pends > VHOST_MAX_PEND)) |
bab632d6 | 384 | break; |
8ea8cf89 MT |
385 | if (unlikely(vhost_enable_notify(&net->dev, vq))) { |
386 | vhost_disable_notify(&net->dev, vq); | |
3a4d5c94 MT |
387 | continue; |
388 | } | |
389 | break; | |
390 | } | |
391 | if (in) { | |
392 | vq_err(vq, "Unexpected descriptor format for TX: " | |
393 | "out %d, int %d\n", out, in); | |
394 | break; | |
395 | } | |
396 | /* Skip header. TODO: support TSO. */ | |
81f95a55 | 397 | s = move_iovec_hdr(vq->iov, nvq->hdr, hdr_size, out); |
3a4d5c94 MT |
398 | msg.msg_iovlen = out; |
399 | len = iov_length(vq->iov, out); | |
400 | /* Sanity check */ | |
401 | if (!len) { | |
402 | vq_err(vq, "Unexpected header len for TX: " | |
403 | "%zd expected %zd\n", | |
81f95a55 | 404 | iov_length(nvq->hdr, s), hdr_size); |
3a4d5c94 MT |
405 | break; |
406 | } | |
cedb9bdc | 407 | zcopy_used = zcopy && (len >= VHOST_GOODCOPY_LEN || |
2839400f | 408 | nvq->upend_idx != nvq->done_idx); |
cedb9bdc | 409 | |
bab632d6 | 410 | /* use msg_control to pass vhost zerocopy ubuf info to skb */ |
cedb9bdc | 411 | if (zcopy_used) { |
2839400f | 412 | vq->heads[nvq->upend_idx].id = head; |
eaae8132 MT |
413 | if (!vhost_net_tx_select_zcopy(net) || |
414 | len < VHOST_GOODCOPY_LEN) { | |
bab632d6 | 415 | /* copy don't need to wait for DMA done */ |
2839400f | 416 | vq->heads[nvq->upend_idx].len = |
bab632d6 MT |
417 | VHOST_DMA_DONE_LEN; |
418 | msg.msg_control = NULL; | |
419 | msg.msg_controllen = 0; | |
420 | ubufs = NULL; | |
421 | } else { | |
46aa92d1 | 422 | struct ubuf_info *ubuf; |
2839400f | 423 | ubuf = nvq->ubuf_info + nvq->upend_idx; |
bab632d6 | 424 | |
2839400f | 425 | vq->heads[nvq->upend_idx].len = |
70e4cb9a | 426 | VHOST_DMA_IN_PROGRESS; |
bab632d6 | 427 | ubuf->callback = vhost_zerocopy_callback; |
2839400f AH |
428 | ubuf->ctx = nvq->ubufs; |
429 | ubuf->desc = nvq->upend_idx; | |
bab632d6 MT |
430 | msg.msg_control = ubuf; |
431 | msg.msg_controllen = sizeof(ubuf); | |
2839400f | 432 | ubufs = nvq->ubufs; |
bab632d6 MT |
433 | kref_get(&ubufs->kref); |
434 | } | |
2839400f | 435 | nvq->upend_idx = (nvq->upend_idx + 1) % UIO_MAXIOV; |
4364d5f9 JW |
436 | } else |
437 | msg.msg_control = NULL; | |
3a4d5c94 MT |
438 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ |
439 | err = sock->ops->sendmsg(NULL, sock, &msg, len); | |
440 | if (unlikely(err < 0)) { | |
cedb9bdc | 441 | if (zcopy_used) { |
bab632d6 | 442 | if (ubufs) |
fe729a57 | 443 | vhost_net_ubuf_put(ubufs); |
2839400f AH |
444 | nvq->upend_idx = ((unsigned)nvq->upend_idx - 1) |
445 | % UIO_MAXIOV; | |
bab632d6 | 446 | } |
8dd014ad | 447 | vhost_discard_vq_desc(vq, 1); |
3a4d5c94 MT |
448 | break; |
449 | } | |
450 | if (err != len) | |
95c0ec6a MT |
451 | pr_debug("Truncated TX packet: " |
452 | " len %d != %zd\n", err, len); | |
cedb9bdc | 453 | if (!zcopy_used) |
bab632d6 | 454 | vhost_add_used_and_signal(&net->dev, vq, head, 0); |
c8fb217a | 455 | else |
eaae8132 | 456 | vhost_zerocopy_signal_used(net, vq); |
3a4d5c94 | 457 | total_len += len; |
eaae8132 | 458 | vhost_net_tx_packet(net); |
3a4d5c94 MT |
459 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { |
460 | vhost_poll_queue(&vq->poll); | |
461 | break; | |
462 | } | |
463 | } | |
464 | ||
465 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
466 | } |
467 | ||
8dd014ad DS |
468 | static int peek_head_len(struct sock *sk) |
469 | { | |
470 | struct sk_buff *head; | |
471 | int len = 0; | |
783e3988 | 472 | unsigned long flags; |
8dd014ad | 473 | |
783e3988 | 474 | spin_lock_irqsave(&sk->sk_receive_queue.lock, flags); |
8dd014ad | 475 | head = skb_peek(&sk->sk_receive_queue); |
c53cff5e | 476 | if (likely(head)) { |
8dd014ad | 477 | len = head->len; |
c53cff5e BG |
478 | if (vlan_tx_tag_present(head)) |
479 | len += VLAN_HLEN; | |
480 | } | |
481 | ||
783e3988 | 482 | spin_unlock_irqrestore(&sk->sk_receive_queue.lock, flags); |
8dd014ad DS |
483 | return len; |
484 | } | |
485 | ||
486 | /* This is a multi-buffer version of vhost_get_desc, that works if | |
487 | * vq has read descriptors only. | |
488 | * @vq - the relevant virtqueue | |
489 | * @datalen - data length we'll be reading | |
490 | * @iovcount - returned count of io vectors we fill | |
491 | * @log - vhost log | |
492 | * @log_num - log offset | |
94249369 | 493 | * @quota - headcount quota, 1 for big buffer |
8dd014ad DS |
494 | * returns number of buffer heads allocated, negative on error |
495 | */ | |
496 | static int get_rx_bufs(struct vhost_virtqueue *vq, | |
497 | struct vring_used_elem *heads, | |
498 | int datalen, | |
499 | unsigned *iovcount, | |
500 | struct vhost_log *log, | |
94249369 JW |
501 | unsigned *log_num, |
502 | unsigned int quota) | |
8dd014ad DS |
503 | { |
504 | unsigned int out, in; | |
505 | int seg = 0; | |
506 | int headcount = 0; | |
507 | unsigned d; | |
508 | int r, nlogs = 0; | |
509 | ||
94249369 | 510 | while (datalen > 0 && headcount < quota) { |
e0e9b406 | 511 | if (unlikely(seg >= UIO_MAXIOV)) { |
8dd014ad DS |
512 | r = -ENOBUFS; |
513 | goto err; | |
514 | } | |
515 | d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, | |
516 | ARRAY_SIZE(vq->iov) - seg, &out, | |
517 | &in, log, log_num); | |
518 | if (d == vq->num) { | |
519 | r = 0; | |
520 | goto err; | |
521 | } | |
522 | if (unlikely(out || in <= 0)) { | |
523 | vq_err(vq, "unexpected descriptor format for RX: " | |
524 | "out %d, in %d\n", out, in); | |
525 | r = -EINVAL; | |
526 | goto err; | |
527 | } | |
528 | if (unlikely(log)) { | |
529 | nlogs += *log_num; | |
530 | log += *log_num; | |
531 | } | |
532 | heads[headcount].id = d; | |
533 | heads[headcount].len = iov_length(vq->iov + seg, in); | |
534 | datalen -= heads[headcount].len; | |
535 | ++headcount; | |
536 | seg += in; | |
537 | } | |
538 | heads[headcount - 1].len += datalen; | |
539 | *iovcount = seg; | |
540 | if (unlikely(log)) | |
541 | *log_num = nlogs; | |
542 | return headcount; | |
543 | err: | |
544 | vhost_discard_vq_desc(vq, headcount); | |
545 | return r; | |
546 | } | |
547 | ||
3a4d5c94 MT |
548 | /* Expects to be always run from workqueue - which acts as |
549 | * read-size critical section for our kind of RCU. */ | |
94249369 | 550 | static void handle_rx(struct vhost_net *net) |
3a4d5c94 | 551 | { |
81f95a55 MT |
552 | struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_RX]; |
553 | struct vhost_virtqueue *vq = &nvq->vq; | |
8dd014ad DS |
554 | unsigned uninitialized_var(in), log; |
555 | struct vhost_log *vq_log; | |
556 | struct msghdr msg = { | |
557 | .msg_name = NULL, | |
558 | .msg_namelen = 0, | |
559 | .msg_control = NULL, /* FIXME: get and handle RX aux data. */ | |
560 | .msg_controllen = 0, | |
561 | .msg_iov = vq->iov, | |
562 | .msg_flags = MSG_DONTWAIT, | |
563 | }; | |
8dd014ad DS |
564 | struct virtio_net_hdr_mrg_rxbuf hdr = { |
565 | .hdr.flags = 0, | |
566 | .hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE | |
567 | }; | |
8dd014ad | 568 | size_t total_len = 0; |
910a578f MT |
569 | int err, mergeable; |
570 | s16 headcount; | |
8dd014ad DS |
571 | size_t vhost_hlen, sock_hlen; |
572 | size_t vhost_len, sock_len; | |
5e18247b MT |
573 | /* TODO: check that we are running from vhost_worker? */ |
574 | struct socket *sock = rcu_dereference_check(vq->private_data, 1); | |
d47effe1 | 575 | |
de4d768a | 576 | if (!sock) |
8dd014ad DS |
577 | return; |
578 | ||
8dd014ad | 579 | mutex_lock(&vq->mutex); |
8ea8cf89 | 580 | vhost_disable_notify(&net->dev, vq); |
81f95a55 MT |
581 | vhost_hlen = nvq->vhost_hlen; |
582 | sock_hlen = nvq->sock_hlen; | |
8dd014ad DS |
583 | |
584 | vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? | |
585 | vq->log : NULL; | |
cfbdab95 | 586 | mergeable = vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF); |
8dd014ad DS |
587 | |
588 | while ((sock_len = peek_head_len(sock->sk))) { | |
589 | sock_len += sock_hlen; | |
590 | vhost_len = sock_len + vhost_hlen; | |
591 | headcount = get_rx_bufs(vq, vq->heads, vhost_len, | |
94249369 JW |
592 | &in, vq_log, &log, |
593 | likely(mergeable) ? UIO_MAXIOV : 1); | |
8dd014ad DS |
594 | /* On error, stop handling until the next kick. */ |
595 | if (unlikely(headcount < 0)) | |
596 | break; | |
597 | /* OK, now we need to know about added descriptors. */ | |
598 | if (!headcount) { | |
8ea8cf89 | 599 | if (unlikely(vhost_enable_notify(&net->dev, vq))) { |
8dd014ad DS |
600 | /* They have slipped one in as we were |
601 | * doing that: check again. */ | |
8ea8cf89 | 602 | vhost_disable_notify(&net->dev, vq); |
8dd014ad DS |
603 | continue; |
604 | } | |
605 | /* Nothing new? Wait for eventfd to tell us | |
606 | * they refilled. */ | |
607 | break; | |
608 | } | |
609 | /* We don't need to be notified again. */ | |
610 | if (unlikely((vhost_hlen))) | |
611 | /* Skip header. TODO: support TSO. */ | |
81f95a55 | 612 | move_iovec_hdr(vq->iov, nvq->hdr, vhost_hlen, in); |
8dd014ad DS |
613 | else |
614 | /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: | |
a290aec8 | 615 | * needed because recvmsg can modify msg_iov. */ |
81f95a55 | 616 | copy_iovec_hdr(vq->iov, nvq->hdr, sock_hlen, in); |
8dd014ad DS |
617 | msg.msg_iovlen = in; |
618 | err = sock->ops->recvmsg(NULL, sock, &msg, | |
619 | sock_len, MSG_DONTWAIT | MSG_TRUNC); | |
620 | /* Userspace might have consumed the packet meanwhile: | |
621 | * it's not supposed to do this usually, but might be hard | |
622 | * to prevent. Discard data we got (if any) and keep going. */ | |
623 | if (unlikely(err != sock_len)) { | |
624 | pr_debug("Discarded rx packet: " | |
625 | " len %d, expected %zd\n", err, sock_len); | |
626 | vhost_discard_vq_desc(vq, headcount); | |
627 | continue; | |
628 | } | |
629 | if (unlikely(vhost_hlen) && | |
81f95a55 | 630 | memcpy_toiovecend(nvq->hdr, (unsigned char *)&hdr, 0, |
8dd014ad DS |
631 | vhost_hlen)) { |
632 | vq_err(vq, "Unable to write vnet_hdr at addr %p\n", | |
633 | vq->iov->iov_base); | |
634 | break; | |
635 | } | |
636 | /* TODO: Should check and handle checksum. */ | |
cfbdab95 | 637 | if (likely(mergeable) && |
81f95a55 | 638 | memcpy_toiovecend(nvq->hdr, (unsigned char *)&headcount, |
8dd014ad DS |
639 | offsetof(typeof(hdr), num_buffers), |
640 | sizeof hdr.num_buffers)) { | |
641 | vq_err(vq, "Failed num_buffers write"); | |
642 | vhost_discard_vq_desc(vq, headcount); | |
643 | break; | |
644 | } | |
645 | vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, | |
646 | headcount); | |
647 | if (unlikely(vq_log)) | |
648 | vhost_log_write(vq, vq_log, log, vhost_len); | |
649 | total_len += vhost_len; | |
650 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
651 | vhost_poll_queue(&vq->poll); | |
652 | break; | |
653 | } | |
654 | } | |
655 | ||
656 | mutex_unlock(&vq->mutex); | |
8dd014ad DS |
657 | } |
658 | ||
c23f3445 | 659 | static void handle_tx_kick(struct vhost_work *work) |
3a4d5c94 | 660 | { |
c23f3445 TH |
661 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
662 | poll.work); | |
663 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
664 | ||
3a4d5c94 MT |
665 | handle_tx(net); |
666 | } | |
667 | ||
c23f3445 | 668 | static void handle_rx_kick(struct vhost_work *work) |
3a4d5c94 | 669 | { |
c23f3445 TH |
670 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
671 | poll.work); | |
672 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
673 | ||
3a4d5c94 MT |
674 | handle_rx(net); |
675 | } | |
676 | ||
c23f3445 | 677 | static void handle_tx_net(struct vhost_work *work) |
3a4d5c94 | 678 | { |
c23f3445 TH |
679 | struct vhost_net *net = container_of(work, struct vhost_net, |
680 | poll[VHOST_NET_VQ_TX].work); | |
3a4d5c94 MT |
681 | handle_tx(net); |
682 | } | |
683 | ||
c23f3445 | 684 | static void handle_rx_net(struct vhost_work *work) |
3a4d5c94 | 685 | { |
c23f3445 TH |
686 | struct vhost_net *net = container_of(work, struct vhost_net, |
687 | poll[VHOST_NET_VQ_RX].work); | |
3a4d5c94 MT |
688 | handle_rx(net); |
689 | } | |
690 | ||
691 | static int vhost_net_open(struct inode *inode, struct file *f) | |
692 | { | |
693 | struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); | |
c23f3445 | 694 | struct vhost_dev *dev; |
3ab2e420 | 695 | struct vhost_virtqueue **vqs; |
2839400f | 696 | int r, i; |
c23f3445 | 697 | |
3a4d5c94 MT |
698 | if (!n) |
699 | return -ENOMEM; | |
3ab2e420 AH |
700 | vqs = kmalloc(VHOST_NET_VQ_MAX * sizeof(*vqs), GFP_KERNEL); |
701 | if (!vqs) { | |
702 | kfree(n); | |
703 | return -ENOMEM; | |
704 | } | |
c23f3445 TH |
705 | |
706 | dev = &n->dev; | |
3ab2e420 AH |
707 | vqs[VHOST_NET_VQ_TX] = &n->vqs[VHOST_NET_VQ_TX].vq; |
708 | vqs[VHOST_NET_VQ_RX] = &n->vqs[VHOST_NET_VQ_RX].vq; | |
709 | n->vqs[VHOST_NET_VQ_TX].vq.handle_kick = handle_tx_kick; | |
710 | n->vqs[VHOST_NET_VQ_RX].vq.handle_kick = handle_rx_kick; | |
2839400f AH |
711 | for (i = 0; i < VHOST_NET_VQ_MAX; i++) { |
712 | n->vqs[i].ubufs = NULL; | |
713 | n->vqs[i].ubuf_info = NULL; | |
714 | n->vqs[i].upend_idx = 0; | |
715 | n->vqs[i].done_idx = 0; | |
81f95a55 MT |
716 | n->vqs[i].vhost_hlen = 0; |
717 | n->vqs[i].sock_hlen = 0; | |
2839400f | 718 | } |
3ab2e420 | 719 | r = vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX); |
3a4d5c94 MT |
720 | if (r < 0) { |
721 | kfree(n); | |
3ab2e420 | 722 | kfree(vqs); |
3a4d5c94 MT |
723 | return r; |
724 | } | |
725 | ||
c23f3445 TH |
726 | vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); |
727 | vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); | |
3a4d5c94 MT |
728 | |
729 | f->private_data = n; | |
730 | ||
731 | return 0; | |
732 | } | |
733 | ||
734 | static void vhost_net_disable_vq(struct vhost_net *n, | |
735 | struct vhost_virtqueue *vq) | |
736 | { | |
3ab2e420 AH |
737 | struct vhost_net_virtqueue *nvq = |
738 | container_of(vq, struct vhost_net_virtqueue, vq); | |
739 | struct vhost_poll *poll = n->poll + (nvq - n->vqs); | |
3a4d5c94 MT |
740 | if (!vq->private_data) |
741 | return; | |
70181d51 | 742 | vhost_poll_stop(poll); |
3a4d5c94 MT |
743 | } |
744 | ||
2b8b328b | 745 | static int vhost_net_enable_vq(struct vhost_net *n, |
3a4d5c94 MT |
746 | struct vhost_virtqueue *vq) |
747 | { | |
3ab2e420 AH |
748 | struct vhost_net_virtqueue *nvq = |
749 | container_of(vq, struct vhost_net_virtqueue, vq); | |
750 | struct vhost_poll *poll = n->poll + (nvq - n->vqs); | |
28457ee6 AB |
751 | struct socket *sock; |
752 | ||
753 | sock = rcu_dereference_protected(vq->private_data, | |
754 | lockdep_is_held(&vq->mutex)); | |
3a4d5c94 | 755 | if (!sock) |
2b8b328b | 756 | return 0; |
2b8b328b | 757 | |
70181d51 | 758 | return vhost_poll_start(poll, sock->file); |
3a4d5c94 MT |
759 | } |
760 | ||
761 | static struct socket *vhost_net_stop_vq(struct vhost_net *n, | |
762 | struct vhost_virtqueue *vq) | |
763 | { | |
764 | struct socket *sock; | |
765 | ||
766 | mutex_lock(&vq->mutex); | |
28457ee6 AB |
767 | sock = rcu_dereference_protected(vq->private_data, |
768 | lockdep_is_held(&vq->mutex)); | |
3a4d5c94 MT |
769 | vhost_net_disable_vq(n, vq); |
770 | rcu_assign_pointer(vq->private_data, NULL); | |
771 | mutex_unlock(&vq->mutex); | |
772 | return sock; | |
773 | } | |
774 | ||
775 | static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, | |
776 | struct socket **rx_sock) | |
777 | { | |
3ab2e420 AH |
778 | *tx_sock = vhost_net_stop_vq(n, &n->vqs[VHOST_NET_VQ_TX].vq); |
779 | *rx_sock = vhost_net_stop_vq(n, &n->vqs[VHOST_NET_VQ_RX].vq); | |
3a4d5c94 MT |
780 | } |
781 | ||
782 | static void vhost_net_flush_vq(struct vhost_net *n, int index) | |
783 | { | |
784 | vhost_poll_flush(n->poll + index); | |
3ab2e420 | 785 | vhost_poll_flush(&n->vqs[index].vq.poll); |
3a4d5c94 MT |
786 | } |
787 | ||
788 | static void vhost_net_flush(struct vhost_net *n) | |
789 | { | |
790 | vhost_net_flush_vq(n, VHOST_NET_VQ_TX); | |
791 | vhost_net_flush_vq(n, VHOST_NET_VQ_RX); | |
2839400f | 792 | if (n->vqs[VHOST_NET_VQ_TX].ubufs) { |
3ab2e420 | 793 | mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 794 | n->tx_flush = true; |
3ab2e420 | 795 | mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 796 | /* Wait for all lower device DMAs done. */ |
fe729a57 | 797 | vhost_net_ubuf_put_and_wait(n->vqs[VHOST_NET_VQ_TX].ubufs); |
3ab2e420 | 798 | mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 799 | n->tx_flush = false; |
2839400f | 800 | kref_init(&n->vqs[VHOST_NET_VQ_TX].ubufs->kref); |
3ab2e420 | 801 | mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 802 | } |
3a4d5c94 MT |
803 | } |
804 | ||
805 | static int vhost_net_release(struct inode *inode, struct file *f) | |
806 | { | |
807 | struct vhost_net *n = f->private_data; | |
808 | struct socket *tx_sock; | |
809 | struct socket *rx_sock; | |
810 | ||
811 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
812 | vhost_net_flush(n); | |
b211616d | 813 | vhost_dev_stop(&n->dev); |
ea5d4046 | 814 | vhost_dev_cleanup(&n->dev, false); |
81f95a55 | 815 | vhost_net_vq_reset(n); |
3a4d5c94 MT |
816 | if (tx_sock) |
817 | fput(tx_sock->file); | |
818 | if (rx_sock) | |
819 | fput(rx_sock->file); | |
820 | /* We do an extra flush before freeing memory, | |
821 | * since jobs can re-queue themselves. */ | |
822 | vhost_net_flush(n); | |
3ab2e420 | 823 | kfree(n->dev.vqs); |
3a4d5c94 MT |
824 | kfree(n); |
825 | return 0; | |
826 | } | |
827 | ||
828 | static struct socket *get_raw_socket(int fd) | |
829 | { | |
830 | struct { | |
831 | struct sockaddr_ll sa; | |
832 | char buf[MAX_ADDR_LEN]; | |
833 | } uaddr; | |
834 | int uaddr_len = sizeof uaddr, r; | |
835 | struct socket *sock = sockfd_lookup(fd, &r); | |
d47effe1 | 836 | |
3a4d5c94 MT |
837 | if (!sock) |
838 | return ERR_PTR(-ENOTSOCK); | |
839 | ||
840 | /* Parameter checking */ | |
841 | if (sock->sk->sk_type != SOCK_RAW) { | |
842 | r = -ESOCKTNOSUPPORT; | |
843 | goto err; | |
844 | } | |
845 | ||
846 | r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, | |
847 | &uaddr_len, 0); | |
848 | if (r) | |
849 | goto err; | |
850 | ||
851 | if (uaddr.sa.sll_family != AF_PACKET) { | |
852 | r = -EPFNOSUPPORT; | |
853 | goto err; | |
854 | } | |
855 | return sock; | |
856 | err: | |
857 | fput(sock->file); | |
858 | return ERR_PTR(r); | |
859 | } | |
860 | ||
501c774c | 861 | static struct socket *get_tap_socket(int fd) |
3a4d5c94 MT |
862 | { |
863 | struct file *file = fget(fd); | |
864 | struct socket *sock; | |
d47effe1 | 865 | |
3a4d5c94 MT |
866 | if (!file) |
867 | return ERR_PTR(-EBADF); | |
868 | sock = tun_get_socket(file); | |
501c774c AB |
869 | if (!IS_ERR(sock)) |
870 | return sock; | |
871 | sock = macvtap_get_socket(file); | |
3a4d5c94 MT |
872 | if (IS_ERR(sock)) |
873 | fput(file); | |
874 | return sock; | |
875 | } | |
876 | ||
877 | static struct socket *get_socket(int fd) | |
878 | { | |
879 | struct socket *sock; | |
d47effe1 | 880 | |
3a4d5c94 MT |
881 | /* special case to disable backend */ |
882 | if (fd == -1) | |
883 | return NULL; | |
884 | sock = get_raw_socket(fd); | |
885 | if (!IS_ERR(sock)) | |
886 | return sock; | |
501c774c | 887 | sock = get_tap_socket(fd); |
3a4d5c94 MT |
888 | if (!IS_ERR(sock)) |
889 | return sock; | |
890 | return ERR_PTR(-ENOTSOCK); | |
891 | } | |
892 | ||
893 | static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) | |
894 | { | |
895 | struct socket *sock, *oldsock; | |
896 | struct vhost_virtqueue *vq; | |
2839400f | 897 | struct vhost_net_virtqueue *nvq; |
fe729a57 | 898 | struct vhost_net_ubuf_ref *ubufs, *oldubufs = NULL; |
3a4d5c94 MT |
899 | int r; |
900 | ||
901 | mutex_lock(&n->dev.mutex); | |
902 | r = vhost_dev_check_owner(&n->dev); | |
903 | if (r) | |
904 | goto err; | |
905 | ||
906 | if (index >= VHOST_NET_VQ_MAX) { | |
907 | r = -ENOBUFS; | |
908 | goto err; | |
909 | } | |
3ab2e420 | 910 | vq = &n->vqs[index].vq; |
2839400f | 911 | nvq = &n->vqs[index]; |
3a4d5c94 MT |
912 | mutex_lock(&vq->mutex); |
913 | ||
914 | /* Verify that ring has been setup correctly. */ | |
915 | if (!vhost_vq_access_ok(vq)) { | |
916 | r = -EFAULT; | |
1dace8c8 | 917 | goto err_vq; |
3a4d5c94 MT |
918 | } |
919 | sock = get_socket(fd); | |
920 | if (IS_ERR(sock)) { | |
921 | r = PTR_ERR(sock); | |
1dace8c8 | 922 | goto err_vq; |
3a4d5c94 MT |
923 | } |
924 | ||
925 | /* start polling new socket */ | |
28457ee6 AB |
926 | oldsock = rcu_dereference_protected(vq->private_data, |
927 | lockdep_is_held(&vq->mutex)); | |
11fe8839 | 928 | if (sock != oldsock) { |
fe729a57 AH |
929 | ubufs = vhost_net_ubuf_alloc(vq, |
930 | sock && vhost_sock_zcopy(sock)); | |
bab632d6 MT |
931 | if (IS_ERR(ubufs)) { |
932 | r = PTR_ERR(ubufs); | |
933 | goto err_ubufs; | |
934 | } | |
692a998b | 935 | |
d47effe1 KK |
936 | vhost_net_disable_vq(n, vq); |
937 | rcu_assign_pointer(vq->private_data, sock); | |
f59281da JW |
938 | r = vhost_init_used(vq); |
939 | if (r) | |
692a998b | 940 | goto err_used; |
2b8b328b JW |
941 | r = vhost_net_enable_vq(n, vq); |
942 | if (r) | |
943 | goto err_used; | |
692a998b | 944 | |
2839400f AH |
945 | oldubufs = nvq->ubufs; |
946 | nvq->ubufs = ubufs; | |
64e9a9b8 MT |
947 | |
948 | n->tx_packets = 0; | |
949 | n->tx_zcopy_err = 0; | |
1280c27f | 950 | n->tx_flush = false; |
dd1f4078 | 951 | } |
3a4d5c94 | 952 | |
1680e906 MT |
953 | mutex_unlock(&vq->mutex); |
954 | ||
c047e5f3 | 955 | if (oldubufs) { |
c38e39c3 | 956 | vhost_net_ubuf_put_wait_and_free(oldubufs); |
c047e5f3 | 957 | mutex_lock(&vq->mutex); |
eaae8132 | 958 | vhost_zerocopy_signal_used(n, vq); |
c047e5f3 MT |
959 | mutex_unlock(&vq->mutex); |
960 | } | |
bab632d6 | 961 | |
3a4d5c94 MT |
962 | if (oldsock) { |
963 | vhost_net_flush_vq(n, index); | |
964 | fput(oldsock->file); | |
965 | } | |
1dace8c8 | 966 | |
1680e906 MT |
967 | mutex_unlock(&n->dev.mutex); |
968 | return 0; | |
969 | ||
692a998b JW |
970 | err_used: |
971 | rcu_assign_pointer(vq->private_data, oldsock); | |
972 | vhost_net_enable_vq(n, vq); | |
973 | if (ubufs) | |
c38e39c3 | 974 | vhost_net_ubuf_put_wait_and_free(ubufs); |
bab632d6 MT |
975 | err_ubufs: |
976 | fput(sock->file); | |
1dace8c8 JD |
977 | err_vq: |
978 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
979 | err: |
980 | mutex_unlock(&n->dev.mutex); | |
981 | return r; | |
982 | } | |
983 | ||
984 | static long vhost_net_reset_owner(struct vhost_net *n) | |
985 | { | |
986 | struct socket *tx_sock = NULL; | |
987 | struct socket *rx_sock = NULL; | |
988 | long err; | |
150b9e51 | 989 | struct vhost_memory *memory; |
d47effe1 | 990 | |
3a4d5c94 MT |
991 | mutex_lock(&n->dev.mutex); |
992 | err = vhost_dev_check_owner(&n->dev); | |
993 | if (err) | |
994 | goto done; | |
150b9e51 MT |
995 | memory = vhost_dev_reset_owner_prepare(); |
996 | if (!memory) { | |
997 | err = -ENOMEM; | |
998 | goto done; | |
999 | } | |
3a4d5c94 MT |
1000 | vhost_net_stop(n, &tx_sock, &rx_sock); |
1001 | vhost_net_flush(n); | |
150b9e51 | 1002 | vhost_dev_reset_owner(&n->dev, memory); |
81f95a55 | 1003 | vhost_net_vq_reset(n); |
3a4d5c94 MT |
1004 | done: |
1005 | mutex_unlock(&n->dev.mutex); | |
1006 | if (tx_sock) | |
1007 | fput(tx_sock->file); | |
1008 | if (rx_sock) | |
1009 | fput(rx_sock->file); | |
1010 | return err; | |
1011 | } | |
1012 | ||
1013 | static int vhost_net_set_features(struct vhost_net *n, u64 features) | |
1014 | { | |
8dd014ad | 1015 | size_t vhost_hlen, sock_hlen, hdr_len; |
3a4d5c94 | 1016 | int i; |
8dd014ad DS |
1017 | |
1018 | hdr_len = (features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? | |
1019 | sizeof(struct virtio_net_hdr_mrg_rxbuf) : | |
1020 | sizeof(struct virtio_net_hdr); | |
1021 | if (features & (1 << VHOST_NET_F_VIRTIO_NET_HDR)) { | |
1022 | /* vhost provides vnet_hdr */ | |
1023 | vhost_hlen = hdr_len; | |
1024 | sock_hlen = 0; | |
1025 | } else { | |
1026 | /* socket provides vnet_hdr */ | |
1027 | vhost_hlen = 0; | |
1028 | sock_hlen = hdr_len; | |
1029 | } | |
3a4d5c94 MT |
1030 | mutex_lock(&n->dev.mutex); |
1031 | if ((features & (1 << VHOST_F_LOG_ALL)) && | |
1032 | !vhost_log_access_ok(&n->dev)) { | |
1033 | mutex_unlock(&n->dev.mutex); | |
1034 | return -EFAULT; | |
1035 | } | |
1036 | n->dev.acked_features = features; | |
1037 | smp_wmb(); | |
1038 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { | |
3ab2e420 | 1039 | mutex_lock(&n->vqs[i].vq.mutex); |
81f95a55 MT |
1040 | n->vqs[i].vhost_hlen = vhost_hlen; |
1041 | n->vqs[i].sock_hlen = sock_hlen; | |
3ab2e420 | 1042 | mutex_unlock(&n->vqs[i].vq.mutex); |
3a4d5c94 MT |
1043 | } |
1044 | vhost_net_flush(n); | |
1045 | mutex_unlock(&n->dev.mutex); | |
1046 | return 0; | |
1047 | } | |
1048 | ||
b1ad8496 AH |
1049 | static long vhost_net_set_owner(struct vhost_net *n) |
1050 | { | |
1051 | int r; | |
1052 | ||
1053 | mutex_lock(&n->dev.mutex); | |
05c05351 MT |
1054 | if (vhost_dev_has_owner(&n->dev)) { |
1055 | r = -EBUSY; | |
1056 | goto out; | |
1057 | } | |
b1ad8496 AH |
1058 | r = vhost_net_set_ubuf_info(n); |
1059 | if (r) | |
1060 | goto out; | |
1061 | r = vhost_dev_set_owner(&n->dev); | |
1062 | if (r) | |
1063 | vhost_net_clear_ubuf_info(n); | |
1064 | vhost_net_flush(n); | |
1065 | out: | |
1066 | mutex_unlock(&n->dev.mutex); | |
1067 | return r; | |
1068 | } | |
1069 | ||
3a4d5c94 MT |
1070 | static long vhost_net_ioctl(struct file *f, unsigned int ioctl, |
1071 | unsigned long arg) | |
1072 | { | |
1073 | struct vhost_net *n = f->private_data; | |
1074 | void __user *argp = (void __user *)arg; | |
1075 | u64 __user *featurep = argp; | |
1076 | struct vhost_vring_file backend; | |
1077 | u64 features; | |
1078 | int r; | |
d47effe1 | 1079 | |
3a4d5c94 MT |
1080 | switch (ioctl) { |
1081 | case VHOST_NET_SET_BACKEND: | |
d3553a52 TY |
1082 | if (copy_from_user(&backend, argp, sizeof backend)) |
1083 | return -EFAULT; | |
3a4d5c94 MT |
1084 | return vhost_net_set_backend(n, backend.index, backend.fd); |
1085 | case VHOST_GET_FEATURES: | |
0dd05a3b | 1086 | features = VHOST_NET_FEATURES; |
d3553a52 TY |
1087 | if (copy_to_user(featurep, &features, sizeof features)) |
1088 | return -EFAULT; | |
1089 | return 0; | |
3a4d5c94 | 1090 | case VHOST_SET_FEATURES: |
d3553a52 TY |
1091 | if (copy_from_user(&features, featurep, sizeof features)) |
1092 | return -EFAULT; | |
0dd05a3b | 1093 | if (features & ~VHOST_NET_FEATURES) |
3a4d5c94 MT |
1094 | return -EOPNOTSUPP; |
1095 | return vhost_net_set_features(n, features); | |
1096 | case VHOST_RESET_OWNER: | |
1097 | return vhost_net_reset_owner(n); | |
b1ad8496 AH |
1098 | case VHOST_SET_OWNER: |
1099 | return vhost_net_set_owner(n); | |
3a4d5c94 MT |
1100 | default: |
1101 | mutex_lock(&n->dev.mutex); | |
935cdee7 MT |
1102 | r = vhost_dev_ioctl(&n->dev, ioctl, argp); |
1103 | if (r == -ENOIOCTLCMD) | |
1104 | r = vhost_vring_ioctl(&n->dev, ioctl, argp); | |
1105 | else | |
1106 | vhost_net_flush(n); | |
3a4d5c94 MT |
1107 | mutex_unlock(&n->dev.mutex); |
1108 | return r; | |
1109 | } | |
1110 | } | |
1111 | ||
1112 | #ifdef CONFIG_COMPAT | |
1113 | static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, | |
1114 | unsigned long arg) | |
1115 | { | |
1116 | return vhost_net_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); | |
1117 | } | |
1118 | #endif | |
1119 | ||
373a83a6 | 1120 | static const struct file_operations vhost_net_fops = { |
3a4d5c94 MT |
1121 | .owner = THIS_MODULE, |
1122 | .release = vhost_net_release, | |
1123 | .unlocked_ioctl = vhost_net_ioctl, | |
1124 | #ifdef CONFIG_COMPAT | |
1125 | .compat_ioctl = vhost_net_compat_ioctl, | |
1126 | #endif | |
1127 | .open = vhost_net_open, | |
6038f373 | 1128 | .llseek = noop_llseek, |
3a4d5c94 MT |
1129 | }; |
1130 | ||
1131 | static struct miscdevice vhost_net_misc = { | |
7c7c7f01 | 1132 | .minor = VHOST_NET_MINOR, |
1133 | .name = "vhost-net", | |
1134 | .fops = &vhost_net_fops, | |
3a4d5c94 MT |
1135 | }; |
1136 | ||
a8d3782f | 1137 | static int vhost_net_init(void) |
3a4d5c94 | 1138 | { |
bab632d6 | 1139 | if (experimental_zcopytx) |
fe729a57 | 1140 | vhost_net_enable_zcopy(VHOST_NET_VQ_TX); |
c23f3445 | 1141 | return misc_register(&vhost_net_misc); |
3a4d5c94 MT |
1142 | } |
1143 | module_init(vhost_net_init); | |
1144 | ||
a8d3782f | 1145 | static void vhost_net_exit(void) |
3a4d5c94 MT |
1146 | { |
1147 | misc_deregister(&vhost_net_misc); | |
3a4d5c94 MT |
1148 | } |
1149 | module_exit(vhost_net_exit); | |
1150 | ||
1151 | MODULE_VERSION("0.0.1"); | |
1152 | MODULE_LICENSE("GPL v2"); | |
1153 | MODULE_AUTHOR("Michael S. Tsirkin"); | |
1154 | MODULE_DESCRIPTION("Host kernel accelerator for virtio net"); | |
7c7c7f01 | 1155 | MODULE_ALIAS_MISCDEV(VHOST_NET_MINOR); |
1156 | MODULE_ALIAS("devname:vhost-net"); |