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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> | |
3a4d5c94 | 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> |
c53cff5e | 26 | #include <linux/if_vlan.h> |
3a4d5c94 MT |
27 | |
28 | #include <net/sock.h> | |
29 | ||
30 | #include "vhost.h" | |
31 | ||
f9611c43 | 32 | static int experimental_zcopytx = 1; |
bab632d6 | 33 | module_param(experimental_zcopytx, int, 0444); |
f9611c43 MT |
34 | MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;" |
35 | " 1 -Enable; 0 - Disable"); | |
bab632d6 | 36 | |
3a4d5c94 MT |
37 | /* Max number of bytes transferred before requeueing the job. |
38 | * Using this limit prevents one virtqueue from starving others. */ | |
39 | #define VHOST_NET_WEIGHT 0x80000 | |
40 | ||
bab632d6 MT |
41 | /* MAX number of TX used buffers for outstanding zerocopy */ |
42 | #define VHOST_MAX_PEND 128 | |
43 | #define VHOST_GOODCOPY_LEN 256 | |
44 | ||
eaae8132 MT |
45 | /* |
46 | * For transmit, used buffer len is unused; we override it to track buffer | |
47 | * status internally; used for zerocopy tx only. | |
48 | */ | |
49 | /* Lower device DMA failed */ | |
50 | #define VHOST_DMA_FAILED_LEN 3 | |
51 | /* Lower device DMA done */ | |
52 | #define VHOST_DMA_DONE_LEN 2 | |
53 | /* Lower device DMA in progress */ | |
54 | #define VHOST_DMA_IN_PROGRESS 1 | |
55 | /* Buffer unused */ | |
56 | #define VHOST_DMA_CLEAR_LEN 0 | |
57 | ||
58 | #define VHOST_DMA_IS_DONE(len) ((len) >= VHOST_DMA_DONE_LEN) | |
59 | ||
8570a6e7 AH |
60 | enum { |
61 | VHOST_NET_FEATURES = VHOST_FEATURES | | |
62 | (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | | |
63 | (1ULL << VIRTIO_NET_F_MRG_RXBUF), | |
64 | }; | |
65 | ||
3a4d5c94 MT |
66 | enum { |
67 | VHOST_NET_VQ_RX = 0, | |
68 | VHOST_NET_VQ_TX = 1, | |
69 | VHOST_NET_VQ_MAX = 2, | |
70 | }; | |
71 | ||
fe729a57 | 72 | struct vhost_net_ubuf_ref { |
0ad8b480 MT |
73 | /* refcount follows semantics similar to kref: |
74 | * 0: object is released | |
75 | * 1: no outstanding ubufs | |
76 | * >1: outstanding ubufs | |
77 | */ | |
78 | atomic_t refcount; | |
2839400f AH |
79 | wait_queue_head_t wait; |
80 | struct vhost_virtqueue *vq; | |
81 | }; | |
82 | ||
3ab2e420 AH |
83 | struct vhost_net_virtqueue { |
84 | struct vhost_virtqueue vq; | |
81f95a55 MT |
85 | /* hdr is used to store the virtio header. |
86 | * Since each iovec has >= 1 byte length, we never need more than | |
87 | * header length entries to store the header. */ | |
88 | struct iovec hdr[sizeof(struct virtio_net_hdr_mrg_rxbuf)]; | |
89 | size_t vhost_hlen; | |
90 | size_t sock_hlen; | |
2839400f AH |
91 | /* vhost zerocopy support fields below: */ |
92 | /* last used idx for outstanding DMA zerocopy buffers */ | |
93 | int upend_idx; | |
94 | /* first used idx for DMA done zerocopy buffers */ | |
95 | int done_idx; | |
96 | /* an array of userspace buffers info */ | |
97 | struct ubuf_info *ubuf_info; | |
98 | /* Reference counting for outstanding ubufs. | |
99 | * Protected by vq mutex. Writers must also take device mutex. */ | |
fe729a57 | 100 | struct vhost_net_ubuf_ref *ubufs; |
3ab2e420 AH |
101 | }; |
102 | ||
3a4d5c94 MT |
103 | struct vhost_net { |
104 | struct vhost_dev dev; | |
3ab2e420 | 105 | struct vhost_net_virtqueue vqs[VHOST_NET_VQ_MAX]; |
3a4d5c94 | 106 | struct vhost_poll poll[VHOST_NET_VQ_MAX]; |
eaae8132 MT |
107 | /* Number of TX recently submitted. |
108 | * Protected by tx vq lock. */ | |
109 | unsigned tx_packets; | |
110 | /* Number of times zerocopy TX recently failed. | |
111 | * Protected by tx vq lock. */ | |
112 | unsigned tx_zcopy_err; | |
1280c27f MT |
113 | /* Flush in progress. Protected by tx vq lock. */ |
114 | bool tx_flush; | |
3a4d5c94 MT |
115 | }; |
116 | ||
fe729a57 | 117 | static unsigned vhost_net_zcopy_mask __read_mostly; |
2839400f | 118 | |
fe729a57 | 119 | static void vhost_net_enable_zcopy(int vq) |
2839400f | 120 | { |
fe729a57 | 121 | vhost_net_zcopy_mask |= 0x1 << vq; |
2839400f AH |
122 | } |
123 | ||
fe729a57 AH |
124 | static struct vhost_net_ubuf_ref * |
125 | vhost_net_ubuf_alloc(struct vhost_virtqueue *vq, bool zcopy) | |
2839400f | 126 | { |
fe729a57 | 127 | struct vhost_net_ubuf_ref *ubufs; |
2839400f AH |
128 | /* No zero copy backend? Nothing to count. */ |
129 | if (!zcopy) | |
130 | return NULL; | |
131 | ubufs = kmalloc(sizeof(*ubufs), GFP_KERNEL); | |
132 | if (!ubufs) | |
133 | return ERR_PTR(-ENOMEM); | |
0ad8b480 | 134 | atomic_set(&ubufs->refcount, 1); |
2839400f AH |
135 | init_waitqueue_head(&ubufs->wait); |
136 | ubufs->vq = vq; | |
137 | return ubufs; | |
138 | } | |
139 | ||
0ad8b480 | 140 | static int vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) |
2839400f | 141 | { |
0ad8b480 MT |
142 | int r = atomic_sub_return(1, &ubufs->refcount); |
143 | if (unlikely(!r)) | |
144 | wake_up(&ubufs->wait); | |
145 | return r; | |
2839400f AH |
146 | } |
147 | ||
fe729a57 | 148 | static void vhost_net_ubuf_put_and_wait(struct vhost_net_ubuf_ref *ubufs) |
2839400f | 149 | { |
0ad8b480 MT |
150 | vhost_net_ubuf_put(ubufs); |
151 | wait_event(ubufs->wait, !atomic_read(&ubufs->refcount)); | |
c38e39c3 MT |
152 | } |
153 | ||
154 | static void vhost_net_ubuf_put_wait_and_free(struct vhost_net_ubuf_ref *ubufs) | |
155 | { | |
156 | vhost_net_ubuf_put_and_wait(ubufs); | |
2839400f AH |
157 | kfree(ubufs); |
158 | } | |
159 | ||
b1ad8496 AH |
160 | static void vhost_net_clear_ubuf_info(struct vhost_net *n) |
161 | { | |
b1ad8496 AH |
162 | int i; |
163 | ||
288cfe78 MT |
164 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { |
165 | kfree(n->vqs[i].ubuf_info); | |
166 | n->vqs[i].ubuf_info = NULL; | |
b1ad8496 AH |
167 | } |
168 | } | |
169 | ||
0a1febf7 | 170 | static int vhost_net_set_ubuf_info(struct vhost_net *n) |
2839400f AH |
171 | { |
172 | bool zcopy; | |
173 | int i; | |
174 | ||
288cfe78 | 175 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { |
fe729a57 | 176 | zcopy = vhost_net_zcopy_mask & (0x1 << i); |
2839400f AH |
177 | if (!zcopy) |
178 | continue; | |
179 | n->vqs[i].ubuf_info = kmalloc(sizeof(*n->vqs[i].ubuf_info) * | |
180 | UIO_MAXIOV, GFP_KERNEL); | |
181 | if (!n->vqs[i].ubuf_info) | |
182 | goto err; | |
183 | } | |
184 | return 0; | |
185 | ||
186 | err: | |
288cfe78 | 187 | vhost_net_clear_ubuf_info(n); |
2839400f AH |
188 | return -ENOMEM; |
189 | } | |
190 | ||
0a1febf7 | 191 | static void vhost_net_vq_reset(struct vhost_net *n) |
2839400f AH |
192 | { |
193 | int i; | |
194 | ||
288cfe78 MT |
195 | vhost_net_clear_ubuf_info(n); |
196 | ||
2839400f AH |
197 | for (i = 0; i < VHOST_NET_VQ_MAX; i++) { |
198 | n->vqs[i].done_idx = 0; | |
199 | n->vqs[i].upend_idx = 0; | |
200 | n->vqs[i].ubufs = NULL; | |
81f95a55 MT |
201 | n->vqs[i].vhost_hlen = 0; |
202 | n->vqs[i].sock_hlen = 0; | |
2839400f AH |
203 | } |
204 | ||
205 | } | |
206 | ||
eaae8132 MT |
207 | static void vhost_net_tx_packet(struct vhost_net *net) |
208 | { | |
209 | ++net->tx_packets; | |
210 | if (net->tx_packets < 1024) | |
211 | return; | |
212 | net->tx_packets = 0; | |
213 | net->tx_zcopy_err = 0; | |
214 | } | |
215 | ||
216 | static void vhost_net_tx_err(struct vhost_net *net) | |
217 | { | |
218 | ++net->tx_zcopy_err; | |
219 | } | |
220 | ||
221 | static bool vhost_net_tx_select_zcopy(struct vhost_net *net) | |
222 | { | |
1280c27f MT |
223 | /* TX flush waits for outstanding DMAs to be done. |
224 | * Don't start new DMAs. | |
225 | */ | |
226 | return !net->tx_flush && | |
227 | net->tx_packets / 64 >= net->tx_zcopy_err; | |
eaae8132 MT |
228 | } |
229 | ||
bab632d6 MT |
230 | static bool vhost_sock_zcopy(struct socket *sock) |
231 | { | |
232 | return unlikely(experimental_zcopytx) && | |
233 | sock_flag(sock->sk, SOCK_ZEROCOPY); | |
234 | } | |
235 | ||
3a4d5c94 MT |
236 | /* Pop first len bytes from iovec. Return number of segments used. */ |
237 | static int move_iovec_hdr(struct iovec *from, struct iovec *to, | |
238 | size_t len, int iov_count) | |
239 | { | |
240 | int seg = 0; | |
241 | size_t size; | |
d47effe1 | 242 | |
3a4d5c94 MT |
243 | while (len && seg < iov_count) { |
244 | size = min(from->iov_len, len); | |
245 | to->iov_base = from->iov_base; | |
246 | to->iov_len = size; | |
247 | from->iov_len -= size; | |
248 | from->iov_base += size; | |
249 | len -= size; | |
250 | ++from; | |
251 | ++to; | |
252 | ++seg; | |
253 | } | |
254 | return seg; | |
255 | } | |
8dd014ad DS |
256 | /* Copy iovec entries for len bytes from iovec. */ |
257 | static void copy_iovec_hdr(const struct iovec *from, struct iovec *to, | |
258 | size_t len, int iovcount) | |
259 | { | |
260 | int seg = 0; | |
261 | size_t size; | |
d47effe1 | 262 | |
8dd014ad DS |
263 | while (len && seg < iovcount) { |
264 | size = min(from->iov_len, len); | |
265 | to->iov_base = from->iov_base; | |
266 | to->iov_len = size; | |
267 | len -= size; | |
268 | ++from; | |
269 | ++to; | |
270 | ++seg; | |
271 | } | |
272 | } | |
3a4d5c94 | 273 | |
b211616d MT |
274 | /* In case of DMA done not in order in lower device driver for some reason. |
275 | * upend_idx is used to track end of used idx, done_idx is used to track head | |
276 | * of used idx. Once lower device DMA done contiguously, we will signal KVM | |
277 | * guest used idx. | |
278 | */ | |
094afe7d JW |
279 | static void vhost_zerocopy_signal_used(struct vhost_net *net, |
280 | struct vhost_virtqueue *vq) | |
b211616d | 281 | { |
2839400f AH |
282 | struct vhost_net_virtqueue *nvq = |
283 | container_of(vq, struct vhost_net_virtqueue, vq); | |
c92112ae | 284 | int i, add; |
b211616d MT |
285 | int j = 0; |
286 | ||
2839400f | 287 | for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) { |
eaae8132 MT |
288 | if (vq->heads[i].len == VHOST_DMA_FAILED_LEN) |
289 | vhost_net_tx_err(net); | |
b211616d MT |
290 | if (VHOST_DMA_IS_DONE(vq->heads[i].len)) { |
291 | vq->heads[i].len = VHOST_DMA_CLEAR_LEN; | |
b211616d MT |
292 | ++j; |
293 | } else | |
294 | break; | |
295 | } | |
c92112ae JW |
296 | while (j) { |
297 | add = min(UIO_MAXIOV - nvq->done_idx, j); | |
298 | vhost_add_used_and_signal_n(vq->dev, vq, | |
299 | &vq->heads[nvq->done_idx], add); | |
300 | nvq->done_idx = (nvq->done_idx + add) % UIO_MAXIOV; | |
301 | j -= add; | |
302 | } | |
b211616d MT |
303 | } |
304 | ||
eaae8132 | 305 | static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) |
b211616d | 306 | { |
fe729a57 | 307 | struct vhost_net_ubuf_ref *ubufs = ubuf->ctx; |
b211616d | 308 | struct vhost_virtqueue *vq = ubufs->vq; |
0ad8b480 | 309 | int cnt; |
24eb21a1 | 310 | |
b0c057ca MT |
311 | rcu_read_lock_bh(); |
312 | ||
19c73b3e JW |
313 | /* set len to mark this desc buffers done DMA */ |
314 | vq->heads[ubuf->desc].len = success ? | |
315 | VHOST_DMA_DONE_LEN : VHOST_DMA_FAILED_LEN; | |
0ad8b480 | 316 | cnt = vhost_net_ubuf_put(ubufs); |
19c73b3e | 317 | |
24eb21a1 MT |
318 | /* |
319 | * Trigger polling thread if guest stopped submitting new buffers: | |
0ad8b480 | 320 | * in this case, the refcount after decrement will eventually reach 1. |
24eb21a1 MT |
321 | * We also trigger polling periodically after each 16 packets |
322 | * (the value 16 here is more or less arbitrary, it's tuned to trigger | |
323 | * less than 10% of times). | |
324 | */ | |
0ad8b480 | 325 | if (cnt <= 1 || !(cnt % 16)) |
24eb21a1 | 326 | vhost_poll_queue(&vq->poll); |
b0c057ca MT |
327 | |
328 | rcu_read_unlock_bh(); | |
b211616d MT |
329 | } |
330 | ||
3a4d5c94 MT |
331 | /* Expects to be always run from workqueue - which acts as |
332 | * read-size critical section for our kind of RCU. */ | |
333 | static void handle_tx(struct vhost_net *net) | |
334 | { | |
2839400f | 335 | struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; |
81f95a55 | 336 | struct vhost_virtqueue *vq = &nvq->vq; |
d5675bd2 MT |
337 | unsigned out, in, s; |
338 | int head; | |
3a4d5c94 MT |
339 | struct msghdr msg = { |
340 | .msg_name = NULL, | |
341 | .msg_namelen = 0, | |
342 | .msg_control = NULL, | |
343 | .msg_controllen = 0, | |
344 | .msg_iov = vq->iov, | |
345 | .msg_flags = MSG_DONTWAIT, | |
346 | }; | |
347 | size_t len, total_len = 0; | |
70181d51 | 348 | int err; |
3a4d5c94 | 349 | size_t hdr_size; |
28457ee6 | 350 | struct socket *sock; |
fe729a57 | 351 | struct vhost_net_ubuf_ref *uninitialized_var(ubufs); |
cedb9bdc | 352 | bool zcopy, zcopy_used; |
28457ee6 | 353 | |
2e26af79 AH |
354 | mutex_lock(&vq->mutex); |
355 | sock = vq->private_data; | |
3a4d5c94 | 356 | if (!sock) |
2e26af79 | 357 | goto out; |
3a4d5c94 | 358 | |
8ea8cf89 | 359 | vhost_disable_notify(&net->dev, vq); |
3a4d5c94 | 360 | |
81f95a55 | 361 | hdr_size = nvq->vhost_hlen; |
2839400f | 362 | zcopy = nvq->ubufs; |
3a4d5c94 MT |
363 | |
364 | for (;;) { | |
bab632d6 MT |
365 | /* Release DMAs done buffers first */ |
366 | if (zcopy) | |
eaae8132 | 367 | vhost_zerocopy_signal_used(net, vq); |
bab632d6 | 368 | |
f7c6be40 JW |
369 | /* If more outstanding DMAs, queue the work. |
370 | * Handle upend_idx wrap around | |
371 | */ | |
372 | if (unlikely((nvq->upend_idx + vq->num - VHOST_MAX_PEND) | |
373 | % UIO_MAXIOV == nvq->done_idx)) | |
374 | break; | |
375 | ||
3a4d5c94 MT |
376 | head = vhost_get_vq_desc(&net->dev, vq, vq->iov, |
377 | ARRAY_SIZE(vq->iov), | |
378 | &out, &in, | |
379 | NULL, NULL); | |
d5675bd2 | 380 | /* On error, stop handling until the next kick. */ |
7b3384fc | 381 | if (unlikely(head < 0)) |
d5675bd2 | 382 | break; |
3a4d5c94 MT |
383 | /* Nothing new? Wait for eventfd to tell us they refilled. */ |
384 | if (head == vq->num) { | |
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 | } | |
ce21a029 JW |
407 | |
408 | zcopy_used = zcopy && len >= VHOST_GOODCOPY_LEN | |
409 | && (nvq->upend_idx + 1) % UIO_MAXIOV != | |
410 | nvq->done_idx | |
411 | && vhost_net_tx_select_zcopy(net); | |
cedb9bdc | 412 | |
bab632d6 | 413 | /* use msg_control to pass vhost zerocopy ubuf info to skb */ |
cedb9bdc | 414 | if (zcopy_used) { |
ce21a029 JW |
415 | struct ubuf_info *ubuf; |
416 | ubuf = nvq->ubuf_info + nvq->upend_idx; | |
417 | ||
2839400f | 418 | vq->heads[nvq->upend_idx].id = head; |
ce21a029 JW |
419 | vq->heads[nvq->upend_idx].len = VHOST_DMA_IN_PROGRESS; |
420 | ubuf->callback = vhost_zerocopy_callback; | |
421 | ubuf->ctx = nvq->ubufs; | |
422 | ubuf->desc = nvq->upend_idx; | |
423 | msg.msg_control = ubuf; | |
424 | msg.msg_controllen = sizeof(ubuf); | |
425 | ubufs = nvq->ubufs; | |
0ad8b480 | 426 | atomic_inc(&ubufs->refcount); |
2839400f | 427 | nvq->upend_idx = (nvq->upend_idx + 1) % UIO_MAXIOV; |
ce21a029 | 428 | } else { |
4364d5f9 | 429 | msg.msg_control = NULL; |
ce21a029 JW |
430 | ubufs = NULL; |
431 | } | |
3a4d5c94 MT |
432 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ |
433 | err = sock->ops->sendmsg(NULL, sock, &msg, len); | |
434 | if (unlikely(err < 0)) { | |
cedb9bdc | 435 | if (zcopy_used) { |
ce21a029 | 436 | vhost_net_ubuf_put(ubufs); |
2839400f AH |
437 | nvq->upend_idx = ((unsigned)nvq->upend_idx - 1) |
438 | % UIO_MAXIOV; | |
bab632d6 | 439 | } |
8dd014ad | 440 | vhost_discard_vq_desc(vq, 1); |
3a4d5c94 MT |
441 | break; |
442 | } | |
443 | if (err != len) | |
95c0ec6a MT |
444 | pr_debug("Truncated TX packet: " |
445 | " len %d != %zd\n", err, len); | |
cedb9bdc | 446 | if (!zcopy_used) |
bab632d6 | 447 | vhost_add_used_and_signal(&net->dev, vq, head, 0); |
c8fb217a | 448 | else |
eaae8132 | 449 | vhost_zerocopy_signal_used(net, vq); |
3a4d5c94 | 450 | total_len += len; |
eaae8132 | 451 | vhost_net_tx_packet(net); |
3a4d5c94 MT |
452 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { |
453 | vhost_poll_queue(&vq->poll); | |
454 | break; | |
455 | } | |
456 | } | |
2e26af79 | 457 | out: |
3a4d5c94 | 458 | mutex_unlock(&vq->mutex); |
3a4d5c94 MT |
459 | } |
460 | ||
8dd014ad DS |
461 | static int peek_head_len(struct sock *sk) |
462 | { | |
463 | struct sk_buff *head; | |
464 | int len = 0; | |
783e3988 | 465 | unsigned long flags; |
8dd014ad | 466 | |
783e3988 | 467 | spin_lock_irqsave(&sk->sk_receive_queue.lock, flags); |
8dd014ad | 468 | head = skb_peek(&sk->sk_receive_queue); |
c53cff5e | 469 | if (likely(head)) { |
8dd014ad | 470 | len = head->len; |
c53cff5e BG |
471 | if (vlan_tx_tag_present(head)) |
472 | len += VLAN_HLEN; | |
473 | } | |
474 | ||
783e3988 | 475 | spin_unlock_irqrestore(&sk->sk_receive_queue.lock, flags); |
8dd014ad DS |
476 | return len; |
477 | } | |
478 | ||
479 | /* This is a multi-buffer version of vhost_get_desc, that works if | |
480 | * vq has read descriptors only. | |
481 | * @vq - the relevant virtqueue | |
482 | * @datalen - data length we'll be reading | |
483 | * @iovcount - returned count of io vectors we fill | |
484 | * @log - vhost log | |
485 | * @log_num - log offset | |
94249369 | 486 | * @quota - headcount quota, 1 for big buffer |
8dd014ad DS |
487 | * returns number of buffer heads allocated, negative on error |
488 | */ | |
489 | static int get_rx_bufs(struct vhost_virtqueue *vq, | |
490 | struct vring_used_elem *heads, | |
491 | int datalen, | |
492 | unsigned *iovcount, | |
493 | struct vhost_log *log, | |
94249369 JW |
494 | unsigned *log_num, |
495 | unsigned int quota) | |
8dd014ad DS |
496 | { |
497 | unsigned int out, in; | |
498 | int seg = 0; | |
499 | int headcount = 0; | |
500 | unsigned d; | |
501 | int r, nlogs = 0; | |
502 | ||
94249369 | 503 | while (datalen > 0 && headcount < quota) { |
e0e9b406 | 504 | if (unlikely(seg >= UIO_MAXIOV)) { |
8dd014ad DS |
505 | r = -ENOBUFS; |
506 | goto err; | |
507 | } | |
a39ee449 | 508 | r = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, |
8dd014ad DS |
509 | ARRAY_SIZE(vq->iov) - seg, &out, |
510 | &in, log, log_num); | |
a39ee449 MT |
511 | if (unlikely(r < 0)) |
512 | goto err; | |
513 | ||
514 | d = r; | |
8dd014ad DS |
515 | if (d == vq->num) { |
516 | r = 0; | |
517 | goto err; | |
518 | } | |
519 | if (unlikely(out || in <= 0)) { | |
520 | vq_err(vq, "unexpected descriptor format for RX: " | |
521 | "out %d, in %d\n", out, in); | |
522 | r = -EINVAL; | |
523 | goto err; | |
524 | } | |
525 | if (unlikely(log)) { | |
526 | nlogs += *log_num; | |
527 | log += *log_num; | |
528 | } | |
529 | heads[headcount].id = d; | |
530 | heads[headcount].len = iov_length(vq->iov + seg, in); | |
531 | datalen -= heads[headcount].len; | |
532 | ++headcount; | |
533 | seg += in; | |
534 | } | |
535 | heads[headcount - 1].len += datalen; | |
536 | *iovcount = seg; | |
537 | if (unlikely(log)) | |
538 | *log_num = nlogs; | |
d8316f39 MT |
539 | |
540 | /* Detect overrun */ | |
541 | if (unlikely(datalen > 0)) { | |
542 | r = UIO_MAXIOV + 1; | |
543 | goto err; | |
544 | } | |
8dd014ad DS |
545 | return headcount; |
546 | err: | |
547 | vhost_discard_vq_desc(vq, headcount); | |
548 | return r; | |
549 | } | |
550 | ||
3a4d5c94 MT |
551 | /* Expects to be always run from workqueue - which acts as |
552 | * read-size critical section for our kind of RCU. */ | |
94249369 | 553 | static void handle_rx(struct vhost_net *net) |
3a4d5c94 | 554 | { |
81f95a55 MT |
555 | struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_RX]; |
556 | struct vhost_virtqueue *vq = &nvq->vq; | |
8dd014ad DS |
557 | unsigned uninitialized_var(in), log; |
558 | struct vhost_log *vq_log; | |
559 | struct msghdr msg = { | |
560 | .msg_name = NULL, | |
561 | .msg_namelen = 0, | |
562 | .msg_control = NULL, /* FIXME: get and handle RX aux data. */ | |
563 | .msg_controllen = 0, | |
564 | .msg_iov = vq->iov, | |
565 | .msg_flags = MSG_DONTWAIT, | |
566 | }; | |
8dd014ad DS |
567 | struct virtio_net_hdr_mrg_rxbuf hdr = { |
568 | .hdr.flags = 0, | |
569 | .hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE | |
570 | }; | |
8dd014ad | 571 | size_t total_len = 0; |
910a578f MT |
572 | int err, mergeable; |
573 | s16 headcount; | |
8dd014ad DS |
574 | size_t vhost_hlen, sock_hlen; |
575 | size_t vhost_len, sock_len; | |
2e26af79 | 576 | struct socket *sock; |
8dd014ad | 577 | |
8dd014ad | 578 | mutex_lock(&vq->mutex); |
2e26af79 AH |
579 | sock = vq->private_data; |
580 | if (!sock) | |
581 | goto out; | |
8ea8cf89 | 582 | vhost_disable_notify(&net->dev, vq); |
2e26af79 | 583 | |
81f95a55 MT |
584 | vhost_hlen = nvq->vhost_hlen; |
585 | sock_hlen = nvq->sock_hlen; | |
8dd014ad DS |
586 | |
587 | vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? | |
588 | vq->log : NULL; | |
cfbdab95 | 589 | mergeable = vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF); |
8dd014ad DS |
590 | |
591 | while ((sock_len = peek_head_len(sock->sk))) { | |
592 | sock_len += sock_hlen; | |
593 | vhost_len = sock_len + vhost_hlen; | |
594 | headcount = get_rx_bufs(vq, vq->heads, vhost_len, | |
94249369 JW |
595 | &in, vq_log, &log, |
596 | likely(mergeable) ? UIO_MAXIOV : 1); | |
8dd014ad DS |
597 | /* On error, stop handling until the next kick. */ |
598 | if (unlikely(headcount < 0)) | |
599 | break; | |
d8316f39 MT |
600 | /* On overrun, truncate and discard */ |
601 | if (unlikely(headcount > UIO_MAXIOV)) { | |
602 | msg.msg_iovlen = 1; | |
603 | err = sock->ops->recvmsg(NULL, sock, &msg, | |
604 | 1, MSG_DONTWAIT | MSG_TRUNC); | |
605 | pr_debug("Discarded rx packet: len %zd\n", sock_len); | |
606 | continue; | |
607 | } | |
8dd014ad DS |
608 | /* OK, now we need to know about added descriptors. */ |
609 | if (!headcount) { | |
8ea8cf89 | 610 | if (unlikely(vhost_enable_notify(&net->dev, vq))) { |
8dd014ad DS |
611 | /* They have slipped one in as we were |
612 | * doing that: check again. */ | |
8ea8cf89 | 613 | vhost_disable_notify(&net->dev, vq); |
8dd014ad DS |
614 | continue; |
615 | } | |
616 | /* Nothing new? Wait for eventfd to tell us | |
617 | * they refilled. */ | |
618 | break; | |
619 | } | |
620 | /* We don't need to be notified again. */ | |
621 | if (unlikely((vhost_hlen))) | |
622 | /* Skip header. TODO: support TSO. */ | |
81f95a55 | 623 | move_iovec_hdr(vq->iov, nvq->hdr, vhost_hlen, in); |
8dd014ad DS |
624 | else |
625 | /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: | |
a290aec8 | 626 | * needed because recvmsg can modify msg_iov. */ |
81f95a55 | 627 | copy_iovec_hdr(vq->iov, nvq->hdr, sock_hlen, in); |
8dd014ad DS |
628 | msg.msg_iovlen = in; |
629 | err = sock->ops->recvmsg(NULL, sock, &msg, | |
630 | sock_len, MSG_DONTWAIT | MSG_TRUNC); | |
631 | /* Userspace might have consumed the packet meanwhile: | |
632 | * it's not supposed to do this usually, but might be hard | |
633 | * to prevent. Discard data we got (if any) and keep going. */ | |
634 | if (unlikely(err != sock_len)) { | |
635 | pr_debug("Discarded rx packet: " | |
636 | " len %d, expected %zd\n", err, sock_len); | |
637 | vhost_discard_vq_desc(vq, headcount); | |
638 | continue; | |
639 | } | |
640 | if (unlikely(vhost_hlen) && | |
81f95a55 | 641 | memcpy_toiovecend(nvq->hdr, (unsigned char *)&hdr, 0, |
8dd014ad DS |
642 | vhost_hlen)) { |
643 | vq_err(vq, "Unable to write vnet_hdr at addr %p\n", | |
644 | vq->iov->iov_base); | |
645 | break; | |
646 | } | |
647 | /* TODO: Should check and handle checksum. */ | |
cfbdab95 | 648 | if (likely(mergeable) && |
81f95a55 | 649 | memcpy_toiovecend(nvq->hdr, (unsigned char *)&headcount, |
8dd014ad DS |
650 | offsetof(typeof(hdr), num_buffers), |
651 | sizeof hdr.num_buffers)) { | |
652 | vq_err(vq, "Failed num_buffers write"); | |
653 | vhost_discard_vq_desc(vq, headcount); | |
654 | break; | |
655 | } | |
656 | vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, | |
657 | headcount); | |
658 | if (unlikely(vq_log)) | |
659 | vhost_log_write(vq, vq_log, log, vhost_len); | |
660 | total_len += vhost_len; | |
661 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
662 | vhost_poll_queue(&vq->poll); | |
663 | break; | |
664 | } | |
665 | } | |
2e26af79 | 666 | out: |
8dd014ad | 667 | mutex_unlock(&vq->mutex); |
8dd014ad DS |
668 | } |
669 | ||
c23f3445 | 670 | static void handle_tx_kick(struct vhost_work *work) |
3a4d5c94 | 671 | { |
c23f3445 TH |
672 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
673 | poll.work); | |
674 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
675 | ||
3a4d5c94 MT |
676 | handle_tx(net); |
677 | } | |
678 | ||
c23f3445 | 679 | static void handle_rx_kick(struct vhost_work *work) |
3a4d5c94 | 680 | { |
c23f3445 TH |
681 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
682 | poll.work); | |
683 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
684 | ||
3a4d5c94 MT |
685 | handle_rx(net); |
686 | } | |
687 | ||
c23f3445 | 688 | static void handle_tx_net(struct vhost_work *work) |
3a4d5c94 | 689 | { |
c23f3445 TH |
690 | struct vhost_net *net = container_of(work, struct vhost_net, |
691 | poll[VHOST_NET_VQ_TX].work); | |
3a4d5c94 MT |
692 | handle_tx(net); |
693 | } | |
694 | ||
c23f3445 | 695 | static void handle_rx_net(struct vhost_work *work) |
3a4d5c94 | 696 | { |
c23f3445 TH |
697 | struct vhost_net *net = container_of(work, struct vhost_net, |
698 | poll[VHOST_NET_VQ_RX].work); | |
3a4d5c94 MT |
699 | handle_rx(net); |
700 | } | |
701 | ||
702 | static int vhost_net_open(struct inode *inode, struct file *f) | |
703 | { | |
704 | struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); | |
c23f3445 | 705 | struct vhost_dev *dev; |
3ab2e420 | 706 | struct vhost_virtqueue **vqs; |
59566b6e | 707 | int i; |
c23f3445 | 708 | |
3a4d5c94 MT |
709 | if (!n) |
710 | return -ENOMEM; | |
3ab2e420 AH |
711 | vqs = kmalloc(VHOST_NET_VQ_MAX * sizeof(*vqs), GFP_KERNEL); |
712 | if (!vqs) { | |
713 | kfree(n); | |
714 | return -ENOMEM; | |
715 | } | |
c23f3445 TH |
716 | |
717 | dev = &n->dev; | |
3ab2e420 AH |
718 | vqs[VHOST_NET_VQ_TX] = &n->vqs[VHOST_NET_VQ_TX].vq; |
719 | vqs[VHOST_NET_VQ_RX] = &n->vqs[VHOST_NET_VQ_RX].vq; | |
720 | n->vqs[VHOST_NET_VQ_TX].vq.handle_kick = handle_tx_kick; | |
721 | n->vqs[VHOST_NET_VQ_RX].vq.handle_kick = handle_rx_kick; | |
2839400f AH |
722 | for (i = 0; i < VHOST_NET_VQ_MAX; i++) { |
723 | n->vqs[i].ubufs = NULL; | |
724 | n->vqs[i].ubuf_info = NULL; | |
725 | n->vqs[i].upend_idx = 0; | |
726 | n->vqs[i].done_idx = 0; | |
81f95a55 MT |
727 | n->vqs[i].vhost_hlen = 0; |
728 | n->vqs[i].sock_hlen = 0; | |
2839400f | 729 | } |
59566b6e | 730 | vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX); |
3a4d5c94 | 731 | |
c23f3445 TH |
732 | vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); |
733 | vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); | |
3a4d5c94 MT |
734 | |
735 | f->private_data = n; | |
736 | ||
737 | return 0; | |
738 | } | |
739 | ||
740 | static void vhost_net_disable_vq(struct vhost_net *n, | |
741 | struct vhost_virtqueue *vq) | |
742 | { | |
3ab2e420 AH |
743 | struct vhost_net_virtqueue *nvq = |
744 | container_of(vq, struct vhost_net_virtqueue, vq); | |
745 | struct vhost_poll *poll = n->poll + (nvq - n->vqs); | |
3a4d5c94 MT |
746 | if (!vq->private_data) |
747 | return; | |
70181d51 | 748 | vhost_poll_stop(poll); |
3a4d5c94 MT |
749 | } |
750 | ||
2b8b328b | 751 | static int vhost_net_enable_vq(struct vhost_net *n, |
3a4d5c94 MT |
752 | struct vhost_virtqueue *vq) |
753 | { | |
3ab2e420 AH |
754 | struct vhost_net_virtqueue *nvq = |
755 | container_of(vq, struct vhost_net_virtqueue, vq); | |
756 | struct vhost_poll *poll = n->poll + (nvq - n->vqs); | |
28457ee6 AB |
757 | struct socket *sock; |
758 | ||
22fa90c7 | 759 | sock = vq->private_data; |
3a4d5c94 | 760 | if (!sock) |
2b8b328b | 761 | return 0; |
2b8b328b | 762 | |
70181d51 | 763 | return vhost_poll_start(poll, sock->file); |
3a4d5c94 MT |
764 | } |
765 | ||
766 | static struct socket *vhost_net_stop_vq(struct vhost_net *n, | |
767 | struct vhost_virtqueue *vq) | |
768 | { | |
769 | struct socket *sock; | |
770 | ||
771 | mutex_lock(&vq->mutex); | |
22fa90c7 | 772 | sock = vq->private_data; |
3a4d5c94 | 773 | vhost_net_disable_vq(n, vq); |
22fa90c7 | 774 | vq->private_data = NULL; |
3a4d5c94 MT |
775 | mutex_unlock(&vq->mutex); |
776 | return sock; | |
777 | } | |
778 | ||
779 | static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, | |
780 | struct socket **rx_sock) | |
781 | { | |
3ab2e420 AH |
782 | *tx_sock = vhost_net_stop_vq(n, &n->vqs[VHOST_NET_VQ_TX].vq); |
783 | *rx_sock = vhost_net_stop_vq(n, &n->vqs[VHOST_NET_VQ_RX].vq); | |
3a4d5c94 MT |
784 | } |
785 | ||
786 | static void vhost_net_flush_vq(struct vhost_net *n, int index) | |
787 | { | |
788 | vhost_poll_flush(n->poll + index); | |
3ab2e420 | 789 | vhost_poll_flush(&n->vqs[index].vq.poll); |
3a4d5c94 MT |
790 | } |
791 | ||
792 | static void vhost_net_flush(struct vhost_net *n) | |
793 | { | |
794 | vhost_net_flush_vq(n, VHOST_NET_VQ_TX); | |
795 | vhost_net_flush_vq(n, VHOST_NET_VQ_RX); | |
2839400f | 796 | if (n->vqs[VHOST_NET_VQ_TX].ubufs) { |
3ab2e420 | 797 | mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 798 | n->tx_flush = true; |
3ab2e420 | 799 | mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 800 | /* Wait for all lower device DMAs done. */ |
fe729a57 | 801 | vhost_net_ubuf_put_and_wait(n->vqs[VHOST_NET_VQ_TX].ubufs); |
3ab2e420 | 802 | mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 803 | n->tx_flush = false; |
0ad8b480 | 804 | atomic_set(&n->vqs[VHOST_NET_VQ_TX].ubufs->refcount, 1); |
3ab2e420 | 805 | mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 806 | } |
3a4d5c94 MT |
807 | } |
808 | ||
809 | static int vhost_net_release(struct inode *inode, struct file *f) | |
810 | { | |
811 | struct vhost_net *n = f->private_data; | |
812 | struct socket *tx_sock; | |
813 | struct socket *rx_sock; | |
814 | ||
815 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
816 | vhost_net_flush(n); | |
b211616d | 817 | vhost_dev_stop(&n->dev); |
ea5d4046 | 818 | vhost_dev_cleanup(&n->dev, false); |
81f95a55 | 819 | vhost_net_vq_reset(n); |
3a4d5c94 | 820 | if (tx_sock) |
09aaacf0 | 821 | sockfd_put(tx_sock); |
3a4d5c94 | 822 | if (rx_sock) |
09aaacf0 | 823 | sockfd_put(rx_sock); |
b0c057ca MT |
824 | /* Make sure no callbacks are outstanding */ |
825 | synchronize_rcu_bh(); | |
3a4d5c94 MT |
826 | /* We do an extra flush before freeing memory, |
827 | * since jobs can re-queue themselves. */ | |
828 | vhost_net_flush(n); | |
3ab2e420 | 829 | kfree(n->dev.vqs); |
3a4d5c94 MT |
830 | kfree(n); |
831 | return 0; | |
832 | } | |
833 | ||
834 | static struct socket *get_raw_socket(int fd) | |
835 | { | |
836 | struct { | |
837 | struct sockaddr_ll sa; | |
838 | char buf[MAX_ADDR_LEN]; | |
839 | } uaddr; | |
840 | int uaddr_len = sizeof uaddr, r; | |
841 | struct socket *sock = sockfd_lookup(fd, &r); | |
d47effe1 | 842 | |
3a4d5c94 MT |
843 | if (!sock) |
844 | return ERR_PTR(-ENOTSOCK); | |
845 | ||
846 | /* Parameter checking */ | |
847 | if (sock->sk->sk_type != SOCK_RAW) { | |
848 | r = -ESOCKTNOSUPPORT; | |
849 | goto err; | |
850 | } | |
851 | ||
852 | r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, | |
853 | &uaddr_len, 0); | |
854 | if (r) | |
855 | goto err; | |
856 | ||
857 | if (uaddr.sa.sll_family != AF_PACKET) { | |
858 | r = -EPFNOSUPPORT; | |
859 | goto err; | |
860 | } | |
861 | return sock; | |
862 | err: | |
09aaacf0 | 863 | sockfd_put(sock); |
3a4d5c94 MT |
864 | return ERR_PTR(r); |
865 | } | |
866 | ||
501c774c | 867 | static struct socket *get_tap_socket(int fd) |
3a4d5c94 MT |
868 | { |
869 | struct file *file = fget(fd); | |
870 | struct socket *sock; | |
d47effe1 | 871 | |
3a4d5c94 MT |
872 | if (!file) |
873 | return ERR_PTR(-EBADF); | |
874 | sock = tun_get_socket(file); | |
501c774c AB |
875 | if (!IS_ERR(sock)) |
876 | return sock; | |
877 | sock = macvtap_get_socket(file); | |
3a4d5c94 MT |
878 | if (IS_ERR(sock)) |
879 | fput(file); | |
880 | return sock; | |
881 | } | |
882 | ||
883 | static struct socket *get_socket(int fd) | |
884 | { | |
885 | struct socket *sock; | |
d47effe1 | 886 | |
3a4d5c94 MT |
887 | /* special case to disable backend */ |
888 | if (fd == -1) | |
889 | return NULL; | |
890 | sock = get_raw_socket(fd); | |
891 | if (!IS_ERR(sock)) | |
892 | return sock; | |
501c774c | 893 | sock = get_tap_socket(fd); |
3a4d5c94 MT |
894 | if (!IS_ERR(sock)) |
895 | return sock; | |
896 | return ERR_PTR(-ENOTSOCK); | |
897 | } | |
898 | ||
899 | static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) | |
900 | { | |
901 | struct socket *sock, *oldsock; | |
902 | struct vhost_virtqueue *vq; | |
2839400f | 903 | struct vhost_net_virtqueue *nvq; |
fe729a57 | 904 | struct vhost_net_ubuf_ref *ubufs, *oldubufs = NULL; |
3a4d5c94 MT |
905 | int r; |
906 | ||
907 | mutex_lock(&n->dev.mutex); | |
908 | r = vhost_dev_check_owner(&n->dev); | |
909 | if (r) | |
910 | goto err; | |
911 | ||
912 | if (index >= VHOST_NET_VQ_MAX) { | |
913 | r = -ENOBUFS; | |
914 | goto err; | |
915 | } | |
3ab2e420 | 916 | vq = &n->vqs[index].vq; |
2839400f | 917 | nvq = &n->vqs[index]; |
3a4d5c94 MT |
918 | mutex_lock(&vq->mutex); |
919 | ||
920 | /* Verify that ring has been setup correctly. */ | |
921 | if (!vhost_vq_access_ok(vq)) { | |
922 | r = -EFAULT; | |
1dace8c8 | 923 | goto err_vq; |
3a4d5c94 MT |
924 | } |
925 | sock = get_socket(fd); | |
926 | if (IS_ERR(sock)) { | |
927 | r = PTR_ERR(sock); | |
1dace8c8 | 928 | goto err_vq; |
3a4d5c94 MT |
929 | } |
930 | ||
931 | /* start polling new socket */ | |
22fa90c7 | 932 | oldsock = vq->private_data; |
11fe8839 | 933 | if (sock != oldsock) { |
fe729a57 AH |
934 | ubufs = vhost_net_ubuf_alloc(vq, |
935 | sock && vhost_sock_zcopy(sock)); | |
bab632d6 MT |
936 | if (IS_ERR(ubufs)) { |
937 | r = PTR_ERR(ubufs); | |
938 | goto err_ubufs; | |
939 | } | |
692a998b | 940 | |
d47effe1 | 941 | vhost_net_disable_vq(n, vq); |
22fa90c7 | 942 | vq->private_data = sock; |
f59281da JW |
943 | r = vhost_init_used(vq); |
944 | if (r) | |
692a998b | 945 | goto err_used; |
2b8b328b JW |
946 | r = vhost_net_enable_vq(n, vq); |
947 | if (r) | |
948 | goto err_used; | |
692a998b | 949 | |
2839400f AH |
950 | oldubufs = nvq->ubufs; |
951 | nvq->ubufs = ubufs; | |
64e9a9b8 MT |
952 | |
953 | n->tx_packets = 0; | |
954 | n->tx_zcopy_err = 0; | |
1280c27f | 955 | n->tx_flush = false; |
dd1f4078 | 956 | } |
3a4d5c94 | 957 | |
1680e906 MT |
958 | mutex_unlock(&vq->mutex); |
959 | ||
c047e5f3 | 960 | if (oldubufs) { |
c38e39c3 | 961 | vhost_net_ubuf_put_wait_and_free(oldubufs); |
c047e5f3 | 962 | mutex_lock(&vq->mutex); |
eaae8132 | 963 | vhost_zerocopy_signal_used(n, vq); |
c047e5f3 MT |
964 | mutex_unlock(&vq->mutex); |
965 | } | |
bab632d6 | 966 | |
3a4d5c94 MT |
967 | if (oldsock) { |
968 | vhost_net_flush_vq(n, index); | |
09aaacf0 | 969 | sockfd_put(oldsock); |
3a4d5c94 | 970 | } |
1dace8c8 | 971 | |
1680e906 MT |
972 | mutex_unlock(&n->dev.mutex); |
973 | return 0; | |
974 | ||
692a998b | 975 | err_used: |
22fa90c7 | 976 | vq->private_data = oldsock; |
692a998b JW |
977 | vhost_net_enable_vq(n, vq); |
978 | if (ubufs) | |
c38e39c3 | 979 | vhost_net_ubuf_put_wait_and_free(ubufs); |
bab632d6 | 980 | err_ubufs: |
09aaacf0 | 981 | sockfd_put(sock); |
1dace8c8 JD |
982 | err_vq: |
983 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
984 | err: |
985 | mutex_unlock(&n->dev.mutex); | |
986 | return r; | |
987 | } | |
988 | ||
989 | static long vhost_net_reset_owner(struct vhost_net *n) | |
990 | { | |
991 | struct socket *tx_sock = NULL; | |
992 | struct socket *rx_sock = NULL; | |
993 | long err; | |
150b9e51 | 994 | struct vhost_memory *memory; |
d47effe1 | 995 | |
3a4d5c94 MT |
996 | mutex_lock(&n->dev.mutex); |
997 | err = vhost_dev_check_owner(&n->dev); | |
998 | if (err) | |
999 | goto done; | |
150b9e51 MT |
1000 | memory = vhost_dev_reset_owner_prepare(); |
1001 | if (!memory) { | |
1002 | err = -ENOMEM; | |
1003 | goto done; | |
1004 | } | |
3a4d5c94 MT |
1005 | vhost_net_stop(n, &tx_sock, &rx_sock); |
1006 | vhost_net_flush(n); | |
150b9e51 | 1007 | vhost_dev_reset_owner(&n->dev, memory); |
81f95a55 | 1008 | vhost_net_vq_reset(n); |
3a4d5c94 MT |
1009 | done: |
1010 | mutex_unlock(&n->dev.mutex); | |
1011 | if (tx_sock) | |
09aaacf0 | 1012 | sockfd_put(tx_sock); |
3a4d5c94 | 1013 | if (rx_sock) |
09aaacf0 | 1014 | sockfd_put(rx_sock); |
3a4d5c94 MT |
1015 | return err; |
1016 | } | |
1017 | ||
1018 | static int vhost_net_set_features(struct vhost_net *n, u64 features) | |
1019 | { | |
8dd014ad | 1020 | size_t vhost_hlen, sock_hlen, hdr_len; |
3a4d5c94 | 1021 | int i; |
8dd014ad DS |
1022 | |
1023 | hdr_len = (features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? | |
1024 | sizeof(struct virtio_net_hdr_mrg_rxbuf) : | |
1025 | sizeof(struct virtio_net_hdr); | |
1026 | if (features & (1 << VHOST_NET_F_VIRTIO_NET_HDR)) { | |
1027 | /* vhost provides vnet_hdr */ | |
1028 | vhost_hlen = hdr_len; | |
1029 | sock_hlen = 0; | |
1030 | } else { | |
1031 | /* socket provides vnet_hdr */ | |
1032 | vhost_hlen = 0; | |
1033 | sock_hlen = hdr_len; | |
1034 | } | |
3a4d5c94 MT |
1035 | mutex_lock(&n->dev.mutex); |
1036 | if ((features & (1 << VHOST_F_LOG_ALL)) && | |
1037 | !vhost_log_access_ok(&n->dev)) { | |
1038 | mutex_unlock(&n->dev.mutex); | |
1039 | return -EFAULT; | |
1040 | } | |
1041 | n->dev.acked_features = features; | |
1042 | smp_wmb(); | |
1043 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { | |
3ab2e420 | 1044 | mutex_lock(&n->vqs[i].vq.mutex); |
81f95a55 MT |
1045 | n->vqs[i].vhost_hlen = vhost_hlen; |
1046 | n->vqs[i].sock_hlen = sock_hlen; | |
3ab2e420 | 1047 | mutex_unlock(&n->vqs[i].vq.mutex); |
3a4d5c94 MT |
1048 | } |
1049 | vhost_net_flush(n); | |
1050 | mutex_unlock(&n->dev.mutex); | |
1051 | return 0; | |
1052 | } | |
1053 | ||
b1ad8496 AH |
1054 | static long vhost_net_set_owner(struct vhost_net *n) |
1055 | { | |
1056 | int r; | |
1057 | ||
1058 | mutex_lock(&n->dev.mutex); | |
05c05351 MT |
1059 | if (vhost_dev_has_owner(&n->dev)) { |
1060 | r = -EBUSY; | |
1061 | goto out; | |
1062 | } | |
b1ad8496 AH |
1063 | r = vhost_net_set_ubuf_info(n); |
1064 | if (r) | |
1065 | goto out; | |
1066 | r = vhost_dev_set_owner(&n->dev); | |
1067 | if (r) | |
1068 | vhost_net_clear_ubuf_info(n); | |
1069 | vhost_net_flush(n); | |
1070 | out: | |
1071 | mutex_unlock(&n->dev.mutex); | |
1072 | return r; | |
1073 | } | |
1074 | ||
3a4d5c94 MT |
1075 | static long vhost_net_ioctl(struct file *f, unsigned int ioctl, |
1076 | unsigned long arg) | |
1077 | { | |
1078 | struct vhost_net *n = f->private_data; | |
1079 | void __user *argp = (void __user *)arg; | |
1080 | u64 __user *featurep = argp; | |
1081 | struct vhost_vring_file backend; | |
1082 | u64 features; | |
1083 | int r; | |
d47effe1 | 1084 | |
3a4d5c94 MT |
1085 | switch (ioctl) { |
1086 | case VHOST_NET_SET_BACKEND: | |
d3553a52 TY |
1087 | if (copy_from_user(&backend, argp, sizeof backend)) |
1088 | return -EFAULT; | |
3a4d5c94 MT |
1089 | return vhost_net_set_backend(n, backend.index, backend.fd); |
1090 | case VHOST_GET_FEATURES: | |
0dd05a3b | 1091 | features = VHOST_NET_FEATURES; |
d3553a52 TY |
1092 | if (copy_to_user(featurep, &features, sizeof features)) |
1093 | return -EFAULT; | |
1094 | return 0; | |
3a4d5c94 | 1095 | case VHOST_SET_FEATURES: |
d3553a52 TY |
1096 | if (copy_from_user(&features, featurep, sizeof features)) |
1097 | return -EFAULT; | |
0dd05a3b | 1098 | if (features & ~VHOST_NET_FEATURES) |
3a4d5c94 MT |
1099 | return -EOPNOTSUPP; |
1100 | return vhost_net_set_features(n, features); | |
1101 | case VHOST_RESET_OWNER: | |
1102 | return vhost_net_reset_owner(n); | |
b1ad8496 AH |
1103 | case VHOST_SET_OWNER: |
1104 | return vhost_net_set_owner(n); | |
3a4d5c94 MT |
1105 | default: |
1106 | mutex_lock(&n->dev.mutex); | |
935cdee7 MT |
1107 | r = vhost_dev_ioctl(&n->dev, ioctl, argp); |
1108 | if (r == -ENOIOCTLCMD) | |
1109 | r = vhost_vring_ioctl(&n->dev, ioctl, argp); | |
1110 | else | |
1111 | vhost_net_flush(n); | |
3a4d5c94 MT |
1112 | mutex_unlock(&n->dev.mutex); |
1113 | return r; | |
1114 | } | |
1115 | } | |
1116 | ||
1117 | #ifdef CONFIG_COMPAT | |
1118 | static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, | |
1119 | unsigned long arg) | |
1120 | { | |
1121 | return vhost_net_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); | |
1122 | } | |
1123 | #endif | |
1124 | ||
373a83a6 | 1125 | static const struct file_operations vhost_net_fops = { |
3a4d5c94 MT |
1126 | .owner = THIS_MODULE, |
1127 | .release = vhost_net_release, | |
1128 | .unlocked_ioctl = vhost_net_ioctl, | |
1129 | #ifdef CONFIG_COMPAT | |
1130 | .compat_ioctl = vhost_net_compat_ioctl, | |
1131 | #endif | |
1132 | .open = vhost_net_open, | |
6038f373 | 1133 | .llseek = noop_llseek, |
3a4d5c94 MT |
1134 | }; |
1135 | ||
1136 | static struct miscdevice vhost_net_misc = { | |
7c7c7f01 | 1137 | .minor = VHOST_NET_MINOR, |
1138 | .name = "vhost-net", | |
1139 | .fops = &vhost_net_fops, | |
3a4d5c94 MT |
1140 | }; |
1141 | ||
a8d3782f | 1142 | static int vhost_net_init(void) |
3a4d5c94 | 1143 | { |
bab632d6 | 1144 | if (experimental_zcopytx) |
fe729a57 | 1145 | vhost_net_enable_zcopy(VHOST_NET_VQ_TX); |
c23f3445 | 1146 | return misc_register(&vhost_net_misc); |
3a4d5c94 MT |
1147 | } |
1148 | module_init(vhost_net_init); | |
1149 | ||
a8d3782f | 1150 | static void vhost_net_exit(void) |
3a4d5c94 MT |
1151 | { |
1152 | misc_deregister(&vhost_net_misc); | |
3a4d5c94 MT |
1153 | } |
1154 | module_exit(vhost_net_exit); | |
1155 | ||
1156 | MODULE_VERSION("0.0.1"); | |
1157 | MODULE_LICENSE("GPL v2"); | |
1158 | MODULE_AUTHOR("Michael S. Tsirkin"); | |
1159 | MODULE_DESCRIPTION("Host kernel accelerator for virtio net"); | |
7c7c7f01 | 1160 | MODULE_ALIAS_MISCDEV(VHOST_NET_MINOR); |
1161 | MODULE_ALIAS("devname:vhost-net"); |