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> | |
3a4d5c94 | 18 | #include <linux/file.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
23cc5a99 | 20 | #include <linux/vmalloc.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 */ | |
bf995734 | 51 | #define VHOST_DMA_FAILED_LEN ((__force __virtio32)3) |
eaae8132 | 52 | /* Lower device DMA done */ |
bf995734 | 53 | #define VHOST_DMA_DONE_LEN ((__force __virtio32)2) |
eaae8132 | 54 | /* Lower device DMA in progress */ |
bf995734 | 55 | #define VHOST_DMA_IN_PROGRESS ((__force __virtio32)1) |
eaae8132 | 56 | /* Buffer unused */ |
bf995734 | 57 | #define VHOST_DMA_CLEAR_LEN ((__force __virtio32)0) |
eaae8132 | 58 | |
bf995734 | 59 | #define VHOST_DMA_IS_DONE(len) ((__force u32)(len) >= (__force u32)VHOST_DMA_DONE_LEN) |
eaae8132 | 60 | |
8570a6e7 AH |
61 | enum { |
62 | VHOST_NET_FEATURES = VHOST_FEATURES | | |
63 | (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | | |
4e9fa50c | 64 | (1ULL << VIRTIO_NET_F_MRG_RXBUF) |
8570a6e7 AH |
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 { |
0ad8b480 MT |
74 | /* refcount follows semantics similar to kref: |
75 | * 0: object is released | |
76 | * 1: no outstanding ubufs | |
77 | * >1: outstanding ubufs | |
78 | */ | |
79 | atomic_t refcount; | |
2839400f AH |
80 | wait_queue_head_t wait; |
81 | struct vhost_virtqueue *vq; | |
82 | }; | |
83 | ||
3ab2e420 AH |
84 | struct vhost_net_virtqueue { |
85 | struct vhost_virtqueue vq; | |
81f95a55 MT |
86 | size_t vhost_hlen; |
87 | size_t sock_hlen; | |
2839400f AH |
88 | /* vhost zerocopy support fields below: */ |
89 | /* last used idx for outstanding DMA zerocopy buffers */ | |
90 | int upend_idx; | |
91 | /* first used idx for DMA done zerocopy buffers */ | |
92 | int done_idx; | |
93 | /* an array of userspace buffers info */ | |
94 | struct ubuf_info *ubuf_info; | |
95 | /* Reference counting for outstanding ubufs. | |
96 | * Protected by vq mutex. Writers must also take device mutex. */ | |
fe729a57 | 97 | struct vhost_net_ubuf_ref *ubufs; |
3ab2e420 AH |
98 | }; |
99 | ||
3a4d5c94 MT |
100 | struct vhost_net { |
101 | struct vhost_dev dev; | |
3ab2e420 | 102 | struct vhost_net_virtqueue vqs[VHOST_NET_VQ_MAX]; |
3a4d5c94 | 103 | struct vhost_poll poll[VHOST_NET_VQ_MAX]; |
eaae8132 MT |
104 | /* Number of TX recently submitted. |
105 | * Protected by tx vq lock. */ | |
106 | unsigned tx_packets; | |
107 | /* Number of times zerocopy TX recently failed. | |
108 | * Protected by tx vq lock. */ | |
109 | unsigned tx_zcopy_err; | |
1280c27f MT |
110 | /* Flush in progress. Protected by tx vq lock. */ |
111 | bool tx_flush; | |
3a4d5c94 MT |
112 | }; |
113 | ||
fe729a57 | 114 | static unsigned vhost_net_zcopy_mask __read_mostly; |
2839400f | 115 | |
fe729a57 | 116 | static void vhost_net_enable_zcopy(int vq) |
2839400f | 117 | { |
fe729a57 | 118 | vhost_net_zcopy_mask |= 0x1 << vq; |
2839400f AH |
119 | } |
120 | ||
fe729a57 AH |
121 | static struct vhost_net_ubuf_ref * |
122 | vhost_net_ubuf_alloc(struct vhost_virtqueue *vq, bool zcopy) | |
2839400f | 123 | { |
fe729a57 | 124 | struct vhost_net_ubuf_ref *ubufs; |
2839400f AH |
125 | /* No zero copy backend? Nothing to count. */ |
126 | if (!zcopy) | |
127 | return NULL; | |
128 | ubufs = kmalloc(sizeof(*ubufs), GFP_KERNEL); | |
129 | if (!ubufs) | |
130 | return ERR_PTR(-ENOMEM); | |
0ad8b480 | 131 | atomic_set(&ubufs->refcount, 1); |
2839400f AH |
132 | init_waitqueue_head(&ubufs->wait); |
133 | ubufs->vq = vq; | |
134 | return ubufs; | |
135 | } | |
136 | ||
0ad8b480 | 137 | static int vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) |
2839400f | 138 | { |
0ad8b480 MT |
139 | int r = atomic_sub_return(1, &ubufs->refcount); |
140 | if (unlikely(!r)) | |
141 | wake_up(&ubufs->wait); | |
142 | return r; | |
2839400f AH |
143 | } |
144 | ||
fe729a57 | 145 | static void vhost_net_ubuf_put_and_wait(struct vhost_net_ubuf_ref *ubufs) |
2839400f | 146 | { |
0ad8b480 MT |
147 | vhost_net_ubuf_put(ubufs); |
148 | wait_event(ubufs->wait, !atomic_read(&ubufs->refcount)); | |
c38e39c3 MT |
149 | } |
150 | ||
151 | static void vhost_net_ubuf_put_wait_and_free(struct vhost_net_ubuf_ref *ubufs) | |
152 | { | |
153 | vhost_net_ubuf_put_and_wait(ubufs); | |
2839400f AH |
154 | kfree(ubufs); |
155 | } | |
156 | ||
b1ad8496 AH |
157 | static void vhost_net_clear_ubuf_info(struct vhost_net *n) |
158 | { | |
b1ad8496 AH |
159 | int i; |
160 | ||
288cfe78 MT |
161 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { |
162 | kfree(n->vqs[i].ubuf_info); | |
163 | n->vqs[i].ubuf_info = NULL; | |
b1ad8496 AH |
164 | } |
165 | } | |
166 | ||
0a1febf7 | 167 | static int vhost_net_set_ubuf_info(struct vhost_net *n) |
2839400f AH |
168 | { |
169 | bool zcopy; | |
170 | int i; | |
171 | ||
288cfe78 | 172 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { |
fe729a57 | 173 | zcopy = vhost_net_zcopy_mask & (0x1 << i); |
2839400f AH |
174 | if (!zcopy) |
175 | continue; | |
176 | n->vqs[i].ubuf_info = kmalloc(sizeof(*n->vqs[i].ubuf_info) * | |
177 | UIO_MAXIOV, GFP_KERNEL); | |
178 | if (!n->vqs[i].ubuf_info) | |
179 | goto err; | |
180 | } | |
181 | return 0; | |
182 | ||
183 | err: | |
288cfe78 | 184 | vhost_net_clear_ubuf_info(n); |
2839400f AH |
185 | return -ENOMEM; |
186 | } | |
187 | ||
0a1febf7 | 188 | static void vhost_net_vq_reset(struct vhost_net *n) |
2839400f AH |
189 | { |
190 | int i; | |
191 | ||
288cfe78 MT |
192 | vhost_net_clear_ubuf_info(n); |
193 | ||
2839400f AH |
194 | for (i = 0; i < VHOST_NET_VQ_MAX; i++) { |
195 | n->vqs[i].done_idx = 0; | |
196 | n->vqs[i].upend_idx = 0; | |
197 | n->vqs[i].ubufs = NULL; | |
81f95a55 MT |
198 | n->vqs[i].vhost_hlen = 0; |
199 | n->vqs[i].sock_hlen = 0; | |
2839400f AH |
200 | } |
201 | ||
202 | } | |
203 | ||
eaae8132 MT |
204 | static void vhost_net_tx_packet(struct vhost_net *net) |
205 | { | |
206 | ++net->tx_packets; | |
207 | if (net->tx_packets < 1024) | |
208 | return; | |
209 | net->tx_packets = 0; | |
210 | net->tx_zcopy_err = 0; | |
211 | } | |
212 | ||
213 | static void vhost_net_tx_err(struct vhost_net *net) | |
214 | { | |
215 | ++net->tx_zcopy_err; | |
216 | } | |
217 | ||
218 | static bool vhost_net_tx_select_zcopy(struct vhost_net *net) | |
219 | { | |
1280c27f MT |
220 | /* TX flush waits for outstanding DMAs to be done. |
221 | * Don't start new DMAs. | |
222 | */ | |
223 | return !net->tx_flush && | |
224 | net->tx_packets / 64 >= net->tx_zcopy_err; | |
eaae8132 MT |
225 | } |
226 | ||
bab632d6 MT |
227 | static bool vhost_sock_zcopy(struct socket *sock) |
228 | { | |
229 | return unlikely(experimental_zcopytx) && | |
230 | sock_flag(sock->sk, SOCK_ZEROCOPY); | |
231 | } | |
232 | ||
b211616d MT |
233 | /* In case of DMA done not in order in lower device driver for some reason. |
234 | * upend_idx is used to track end of used idx, done_idx is used to track head | |
235 | * of used idx. Once lower device DMA done contiguously, we will signal KVM | |
236 | * guest used idx. | |
237 | */ | |
094afe7d JW |
238 | static void vhost_zerocopy_signal_used(struct vhost_net *net, |
239 | struct vhost_virtqueue *vq) | |
b211616d | 240 | { |
2839400f AH |
241 | struct vhost_net_virtqueue *nvq = |
242 | container_of(vq, struct vhost_net_virtqueue, vq); | |
c92112ae | 243 | int i, add; |
b211616d MT |
244 | int j = 0; |
245 | ||
2839400f | 246 | for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) { |
eaae8132 MT |
247 | if (vq->heads[i].len == VHOST_DMA_FAILED_LEN) |
248 | vhost_net_tx_err(net); | |
b211616d MT |
249 | if (VHOST_DMA_IS_DONE(vq->heads[i].len)) { |
250 | vq->heads[i].len = VHOST_DMA_CLEAR_LEN; | |
b211616d MT |
251 | ++j; |
252 | } else | |
253 | break; | |
254 | } | |
c92112ae JW |
255 | while (j) { |
256 | add = min(UIO_MAXIOV - nvq->done_idx, j); | |
257 | vhost_add_used_and_signal_n(vq->dev, vq, | |
258 | &vq->heads[nvq->done_idx], add); | |
259 | nvq->done_idx = (nvq->done_idx + add) % UIO_MAXIOV; | |
260 | j -= add; | |
261 | } | |
b211616d MT |
262 | } |
263 | ||
eaae8132 | 264 | static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) |
b211616d | 265 | { |
fe729a57 | 266 | struct vhost_net_ubuf_ref *ubufs = ubuf->ctx; |
b211616d | 267 | struct vhost_virtqueue *vq = ubufs->vq; |
0ad8b480 | 268 | int cnt; |
24eb21a1 | 269 | |
b0c057ca MT |
270 | rcu_read_lock_bh(); |
271 | ||
19c73b3e JW |
272 | /* set len to mark this desc buffers done DMA */ |
273 | vq->heads[ubuf->desc].len = success ? | |
274 | VHOST_DMA_DONE_LEN : VHOST_DMA_FAILED_LEN; | |
0ad8b480 | 275 | cnt = vhost_net_ubuf_put(ubufs); |
19c73b3e | 276 | |
24eb21a1 MT |
277 | /* |
278 | * Trigger polling thread if guest stopped submitting new buffers: | |
0ad8b480 | 279 | * in this case, the refcount after decrement will eventually reach 1. |
24eb21a1 MT |
280 | * We also trigger polling periodically after each 16 packets |
281 | * (the value 16 here is more or less arbitrary, it's tuned to trigger | |
282 | * less than 10% of times). | |
283 | */ | |
0ad8b480 | 284 | if (cnt <= 1 || !(cnt % 16)) |
24eb21a1 | 285 | vhost_poll_queue(&vq->poll); |
b0c057ca MT |
286 | |
287 | rcu_read_unlock_bh(); | |
b211616d MT |
288 | } |
289 | ||
03088137 JW |
290 | static inline unsigned long busy_clock(void) |
291 | { | |
292 | return local_clock() >> 10; | |
293 | } | |
294 | ||
295 | static bool vhost_can_busy_poll(struct vhost_dev *dev, | |
296 | unsigned long endtime) | |
297 | { | |
298 | return likely(!need_resched()) && | |
299 | likely(!time_after(busy_clock(), endtime)) && | |
300 | likely(!signal_pending(current)) && | |
301 | !vhost_has_work(dev); | |
302 | } | |
303 | ||
304 | static int vhost_net_tx_get_vq_desc(struct vhost_net *net, | |
305 | struct vhost_virtqueue *vq, | |
306 | struct iovec iov[], unsigned int iov_size, | |
307 | unsigned int *out_num, unsigned int *in_num) | |
308 | { | |
309 | unsigned long uninitialized_var(endtime); | |
310 | int r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), | |
311 | out_num, in_num, NULL, NULL); | |
312 | ||
313 | if (r == vq->num && vq->busyloop_timeout) { | |
314 | preempt_disable(); | |
315 | endtime = busy_clock() + vq->busyloop_timeout; | |
316 | while (vhost_can_busy_poll(vq->dev, endtime) && | |
317 | vhost_vq_avail_empty(vq->dev, vq)) | |
318 | cpu_relax_lowlatency(); | |
319 | preempt_enable(); | |
320 | r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), | |
321 | out_num, in_num, NULL, NULL); | |
322 | } | |
323 | ||
324 | return r; | |
325 | } | |
326 | ||
3a4d5c94 MT |
327 | /* Expects to be always run from workqueue - which acts as |
328 | * read-size critical section for our kind of RCU. */ | |
329 | static void handle_tx(struct vhost_net *net) | |
330 | { | |
2839400f | 331 | struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; |
81f95a55 | 332 | struct vhost_virtqueue *vq = &nvq->vq; |
98a527aa | 333 | unsigned out, in; |
d5675bd2 | 334 | int head; |
3a4d5c94 MT |
335 | struct msghdr msg = { |
336 | .msg_name = NULL, | |
337 | .msg_namelen = 0, | |
338 | .msg_control = NULL, | |
339 | .msg_controllen = 0, | |
3a4d5c94 MT |
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 | |
2e26af79 AH |
349 | mutex_lock(&vq->mutex); |
350 | sock = vq->private_data; | |
3a4d5c94 | 351 | if (!sock) |
2e26af79 | 352 | goto out; |
3a4d5c94 | 353 | |
8ea8cf89 | 354 | vhost_disable_notify(&net->dev, vq); |
3a4d5c94 | 355 | |
81f95a55 | 356 | hdr_size = nvq->vhost_hlen; |
2839400f | 357 | zcopy = nvq->ubufs; |
3a4d5c94 MT |
358 | |
359 | for (;;) { | |
bab632d6 MT |
360 | /* Release DMAs done buffers first */ |
361 | if (zcopy) | |
eaae8132 | 362 | vhost_zerocopy_signal_used(net, vq); |
bab632d6 | 363 | |
f7c6be40 JW |
364 | /* If more outstanding DMAs, queue the work. |
365 | * Handle upend_idx wrap around | |
366 | */ | |
367 | if (unlikely((nvq->upend_idx + vq->num - VHOST_MAX_PEND) | |
368 | % UIO_MAXIOV == nvq->done_idx)) | |
369 | break; | |
370 | ||
03088137 JW |
371 | head = vhost_net_tx_get_vq_desc(net, vq, vq->iov, |
372 | ARRAY_SIZE(vq->iov), | |
373 | &out, &in); | |
d5675bd2 | 374 | /* On error, stop handling until the next kick. */ |
7b3384fc | 375 | if (unlikely(head < 0)) |
d5675bd2 | 376 | break; |
3a4d5c94 MT |
377 | /* Nothing new? Wait for eventfd to tell us they refilled. */ |
378 | if (head == vq->num) { | |
8ea8cf89 MT |
379 | if (unlikely(vhost_enable_notify(&net->dev, vq))) { |
380 | vhost_disable_notify(&net->dev, vq); | |
3a4d5c94 MT |
381 | continue; |
382 | } | |
383 | break; | |
384 | } | |
385 | if (in) { | |
386 | vq_err(vq, "Unexpected descriptor format for TX: " | |
387 | "out %d, int %d\n", out, in); | |
388 | break; | |
389 | } | |
390 | /* Skip header. TODO: support TSO. */ | |
3a4d5c94 | 391 | len = iov_length(vq->iov, out); |
c0371da6 | 392 | iov_iter_init(&msg.msg_iter, WRITE, vq->iov, out, len); |
98a527aa | 393 | iov_iter_advance(&msg.msg_iter, hdr_size); |
3a4d5c94 | 394 | /* Sanity check */ |
01e97e65 | 395 | if (!msg_data_left(&msg)) { |
3a4d5c94 MT |
396 | vq_err(vq, "Unexpected header len for TX: " |
397 | "%zd expected %zd\n", | |
98a527aa | 398 | len, hdr_size); |
3a4d5c94 MT |
399 | break; |
400 | } | |
01e97e65 | 401 | len = msg_data_left(&msg); |
ce21a029 JW |
402 | |
403 | zcopy_used = zcopy && len >= VHOST_GOODCOPY_LEN | |
404 | && (nvq->upend_idx + 1) % UIO_MAXIOV != | |
405 | nvq->done_idx | |
406 | && vhost_net_tx_select_zcopy(net); | |
cedb9bdc | 407 | |
bab632d6 | 408 | /* use msg_control to pass vhost zerocopy ubuf info to skb */ |
cedb9bdc | 409 | if (zcopy_used) { |
ce21a029 JW |
410 | struct ubuf_info *ubuf; |
411 | ubuf = nvq->ubuf_info + nvq->upend_idx; | |
412 | ||
8b38694a | 413 | vq->heads[nvq->upend_idx].id = cpu_to_vhost32(vq, head); |
ce21a029 JW |
414 | vq->heads[nvq->upend_idx].len = VHOST_DMA_IN_PROGRESS; |
415 | ubuf->callback = vhost_zerocopy_callback; | |
416 | ubuf->ctx = nvq->ubufs; | |
417 | ubuf->desc = nvq->upend_idx; | |
418 | msg.msg_control = ubuf; | |
419 | msg.msg_controllen = sizeof(ubuf); | |
420 | ubufs = nvq->ubufs; | |
0ad8b480 | 421 | atomic_inc(&ubufs->refcount); |
2839400f | 422 | nvq->upend_idx = (nvq->upend_idx + 1) % UIO_MAXIOV; |
ce21a029 | 423 | } else { |
4364d5f9 | 424 | msg.msg_control = NULL; |
ce21a029 JW |
425 | ubufs = NULL; |
426 | } | |
3a4d5c94 | 427 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ |
1b784140 | 428 | err = sock->ops->sendmsg(sock, &msg, len); |
3a4d5c94 | 429 | if (unlikely(err < 0)) { |
cedb9bdc | 430 | if (zcopy_used) { |
ce21a029 | 431 | vhost_net_ubuf_put(ubufs); |
2839400f AH |
432 | nvq->upend_idx = ((unsigned)nvq->upend_idx - 1) |
433 | % UIO_MAXIOV; | |
bab632d6 | 434 | } |
8dd014ad | 435 | vhost_discard_vq_desc(vq, 1); |
3a4d5c94 MT |
436 | break; |
437 | } | |
438 | if (err != len) | |
95c0ec6a MT |
439 | pr_debug("Truncated TX packet: " |
440 | " len %d != %zd\n", err, len); | |
cedb9bdc | 441 | if (!zcopy_used) |
bab632d6 | 442 | vhost_add_used_and_signal(&net->dev, vq, head, 0); |
c8fb217a | 443 | else |
eaae8132 | 444 | vhost_zerocopy_signal_used(net, vq); |
3a4d5c94 | 445 | total_len += len; |
eaae8132 | 446 | vhost_net_tx_packet(net); |
3a4d5c94 MT |
447 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { |
448 | vhost_poll_queue(&vq->poll); | |
449 | break; | |
450 | } | |
451 | } | |
2e26af79 | 452 | out: |
3a4d5c94 | 453 | mutex_unlock(&vq->mutex); |
3a4d5c94 MT |
454 | } |
455 | ||
8dd014ad DS |
456 | static int peek_head_len(struct sock *sk) |
457 | { | |
458 | struct sk_buff *head; | |
459 | int len = 0; | |
783e3988 | 460 | unsigned long flags; |
8dd014ad | 461 | |
783e3988 | 462 | spin_lock_irqsave(&sk->sk_receive_queue.lock, flags); |
8dd014ad | 463 | head = skb_peek(&sk->sk_receive_queue); |
c53cff5e | 464 | if (likely(head)) { |
8dd014ad | 465 | len = head->len; |
df8a39de | 466 | if (skb_vlan_tag_present(head)) |
c53cff5e BG |
467 | len += VLAN_HLEN; |
468 | } | |
469 | ||
783e3988 | 470 | spin_unlock_irqrestore(&sk->sk_receive_queue.lock, flags); |
8dd014ad DS |
471 | return len; |
472 | } | |
473 | ||
03088137 JW |
474 | static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk) |
475 | { | |
476 | struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; | |
477 | struct vhost_virtqueue *vq = &nvq->vq; | |
478 | unsigned long uninitialized_var(endtime); | |
479 | int len = peek_head_len(sk); | |
480 | ||
481 | if (!len && vq->busyloop_timeout) { | |
482 | /* Both tx vq and rx socket were polled here */ | |
483 | mutex_lock(&vq->mutex); | |
484 | vhost_disable_notify(&net->dev, vq); | |
485 | ||
486 | preempt_disable(); | |
487 | endtime = busy_clock() + vq->busyloop_timeout; | |
488 | ||
489 | while (vhost_can_busy_poll(&net->dev, endtime) && | |
490 | skb_queue_empty(&sk->sk_receive_queue) && | |
491 | vhost_vq_avail_empty(&net->dev, vq)) | |
492 | cpu_relax_lowlatency(); | |
493 | ||
494 | preempt_enable(); | |
495 | ||
496 | if (vhost_enable_notify(&net->dev, vq)) | |
497 | vhost_poll_queue(&vq->poll); | |
498 | mutex_unlock(&vq->mutex); | |
499 | ||
500 | len = peek_head_len(sk); | |
501 | } | |
502 | ||
503 | return len; | |
504 | } | |
505 | ||
8dd014ad DS |
506 | /* This is a multi-buffer version of vhost_get_desc, that works if |
507 | * vq has read descriptors only. | |
508 | * @vq - the relevant virtqueue | |
509 | * @datalen - data length we'll be reading | |
510 | * @iovcount - returned count of io vectors we fill | |
511 | * @log - vhost log | |
512 | * @log_num - log offset | |
94249369 | 513 | * @quota - headcount quota, 1 for big buffer |
8dd014ad DS |
514 | * returns number of buffer heads allocated, negative on error |
515 | */ | |
516 | static int get_rx_bufs(struct vhost_virtqueue *vq, | |
517 | struct vring_used_elem *heads, | |
518 | int datalen, | |
519 | unsigned *iovcount, | |
520 | struct vhost_log *log, | |
94249369 JW |
521 | unsigned *log_num, |
522 | unsigned int quota) | |
8dd014ad DS |
523 | { |
524 | unsigned int out, in; | |
525 | int seg = 0; | |
526 | int headcount = 0; | |
527 | unsigned d; | |
528 | int r, nlogs = 0; | |
8b38694a MT |
529 | /* len is always initialized before use since we are always called with |
530 | * datalen > 0. | |
531 | */ | |
532 | u32 uninitialized_var(len); | |
8dd014ad | 533 | |
94249369 | 534 | while (datalen > 0 && headcount < quota) { |
e0e9b406 | 535 | if (unlikely(seg >= UIO_MAXIOV)) { |
8dd014ad DS |
536 | r = -ENOBUFS; |
537 | goto err; | |
538 | } | |
47283bef | 539 | r = vhost_get_vq_desc(vq, vq->iov + seg, |
8dd014ad DS |
540 | ARRAY_SIZE(vq->iov) - seg, &out, |
541 | &in, log, log_num); | |
a39ee449 MT |
542 | if (unlikely(r < 0)) |
543 | goto err; | |
544 | ||
545 | d = r; | |
8dd014ad DS |
546 | if (d == vq->num) { |
547 | r = 0; | |
548 | goto err; | |
549 | } | |
550 | if (unlikely(out || in <= 0)) { | |
551 | vq_err(vq, "unexpected descriptor format for RX: " | |
552 | "out %d, in %d\n", out, in); | |
553 | r = -EINVAL; | |
554 | goto err; | |
555 | } | |
556 | if (unlikely(log)) { | |
557 | nlogs += *log_num; | |
558 | log += *log_num; | |
559 | } | |
8b38694a MT |
560 | heads[headcount].id = cpu_to_vhost32(vq, d); |
561 | len = iov_length(vq->iov + seg, in); | |
562 | heads[headcount].len = cpu_to_vhost32(vq, len); | |
563 | datalen -= len; | |
8dd014ad DS |
564 | ++headcount; |
565 | seg += in; | |
566 | } | |
99975cc6 | 567 | heads[headcount - 1].len = cpu_to_vhost32(vq, len + datalen); |
8dd014ad DS |
568 | *iovcount = seg; |
569 | if (unlikely(log)) | |
570 | *log_num = nlogs; | |
d8316f39 MT |
571 | |
572 | /* Detect overrun */ | |
573 | if (unlikely(datalen > 0)) { | |
574 | r = UIO_MAXIOV + 1; | |
575 | goto err; | |
576 | } | |
8dd014ad DS |
577 | return headcount; |
578 | err: | |
579 | vhost_discard_vq_desc(vq, headcount); | |
580 | return r; | |
581 | } | |
582 | ||
3a4d5c94 MT |
583 | /* Expects to be always run from workqueue - which acts as |
584 | * read-size critical section for our kind of RCU. */ | |
94249369 | 585 | static void handle_rx(struct vhost_net *net) |
3a4d5c94 | 586 | { |
81f95a55 MT |
587 | struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_RX]; |
588 | struct vhost_virtqueue *vq = &nvq->vq; | |
8dd014ad DS |
589 | unsigned uninitialized_var(in), log; |
590 | struct vhost_log *vq_log; | |
591 | struct msghdr msg = { | |
592 | .msg_name = NULL, | |
593 | .msg_namelen = 0, | |
594 | .msg_control = NULL, /* FIXME: get and handle RX aux data. */ | |
595 | .msg_controllen = 0, | |
8dd014ad DS |
596 | .msg_flags = MSG_DONTWAIT, |
597 | }; | |
0960b641 JW |
598 | struct virtio_net_hdr hdr = { |
599 | .flags = 0, | |
600 | .gso_type = VIRTIO_NET_HDR_GSO_NONE | |
8dd014ad | 601 | }; |
8dd014ad | 602 | size_t total_len = 0; |
910a578f MT |
603 | int err, mergeable; |
604 | s16 headcount; | |
8dd014ad DS |
605 | size_t vhost_hlen, sock_hlen; |
606 | size_t vhost_len, sock_len; | |
2e26af79 | 607 | struct socket *sock; |
ba7438ae | 608 | struct iov_iter fixup; |
0960b641 | 609 | __virtio16 num_buffers; |
8dd014ad | 610 | |
8dd014ad | 611 | mutex_lock(&vq->mutex); |
2e26af79 AH |
612 | sock = vq->private_data; |
613 | if (!sock) | |
614 | goto out; | |
8ea8cf89 | 615 | vhost_disable_notify(&net->dev, vq); |
2e26af79 | 616 | |
81f95a55 MT |
617 | vhost_hlen = nvq->vhost_hlen; |
618 | sock_hlen = nvq->sock_hlen; | |
8dd014ad | 619 | |
ea16c514 | 620 | vq_log = unlikely(vhost_has_feature(vq, VHOST_F_LOG_ALL)) ? |
8dd014ad | 621 | vq->log : NULL; |
ea16c514 | 622 | mergeable = vhost_has_feature(vq, VIRTIO_NET_F_MRG_RXBUF); |
8dd014ad | 623 | |
03088137 | 624 | while ((sock_len = vhost_net_rx_peek_head_len(net, sock->sk))) { |
8dd014ad DS |
625 | sock_len += sock_hlen; |
626 | vhost_len = sock_len + vhost_hlen; | |
627 | headcount = get_rx_bufs(vq, vq->heads, vhost_len, | |
94249369 JW |
628 | &in, vq_log, &log, |
629 | likely(mergeable) ? UIO_MAXIOV : 1); | |
8dd014ad DS |
630 | /* On error, stop handling until the next kick. */ |
631 | if (unlikely(headcount < 0)) | |
632 | break; | |
d8316f39 MT |
633 | /* On overrun, truncate and discard */ |
634 | if (unlikely(headcount > UIO_MAXIOV)) { | |
c0371da6 | 635 | iov_iter_init(&msg.msg_iter, READ, vq->iov, 1, 1); |
1b784140 | 636 | err = sock->ops->recvmsg(sock, &msg, |
d8316f39 MT |
637 | 1, MSG_DONTWAIT | MSG_TRUNC); |
638 | pr_debug("Discarded rx packet: len %zd\n", sock_len); | |
639 | continue; | |
640 | } | |
8dd014ad DS |
641 | /* OK, now we need to know about added descriptors. */ |
642 | if (!headcount) { | |
8ea8cf89 | 643 | if (unlikely(vhost_enable_notify(&net->dev, vq))) { |
8dd014ad DS |
644 | /* They have slipped one in as we were |
645 | * doing that: check again. */ | |
8ea8cf89 | 646 | vhost_disable_notify(&net->dev, vq); |
8dd014ad DS |
647 | continue; |
648 | } | |
649 | /* Nothing new? Wait for eventfd to tell us | |
650 | * they refilled. */ | |
651 | break; | |
652 | } | |
653 | /* We don't need to be notified again. */ | |
ba7438ae AV |
654 | iov_iter_init(&msg.msg_iter, READ, vq->iov, in, vhost_len); |
655 | fixup = msg.msg_iter; | |
656 | if (unlikely((vhost_hlen))) { | |
657 | /* We will supply the header ourselves | |
658 | * TODO: support TSO. | |
659 | */ | |
660 | iov_iter_advance(&msg.msg_iter, vhost_hlen); | |
ba7438ae | 661 | } |
1b784140 | 662 | err = sock->ops->recvmsg(sock, &msg, |
8dd014ad DS |
663 | sock_len, MSG_DONTWAIT | MSG_TRUNC); |
664 | /* Userspace might have consumed the packet meanwhile: | |
665 | * it's not supposed to do this usually, but might be hard | |
666 | * to prevent. Discard data we got (if any) and keep going. */ | |
667 | if (unlikely(err != sock_len)) { | |
668 | pr_debug("Discarded rx packet: " | |
669 | " len %d, expected %zd\n", err, sock_len); | |
670 | vhost_discard_vq_desc(vq, headcount); | |
671 | continue; | |
672 | } | |
ba7438ae | 673 | /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ |
4c5a8442 MT |
674 | if (unlikely(vhost_hlen)) { |
675 | if (copy_to_iter(&hdr, sizeof(hdr), | |
676 | &fixup) != sizeof(hdr)) { | |
677 | vq_err(vq, "Unable to write vnet_hdr " | |
678 | "at addr %p\n", vq->iov->iov_base); | |
679 | break; | |
680 | } | |
681 | } else { | |
682 | /* Header came from socket; we'll need to patch | |
683 | * ->num_buffers over if VIRTIO_NET_F_MRG_RXBUF | |
684 | */ | |
685 | iov_iter_advance(&fixup, sizeof(hdr)); | |
8dd014ad DS |
686 | } |
687 | /* TODO: Should check and handle checksum. */ | |
5201aa49 | 688 | |
0960b641 | 689 | num_buffers = cpu_to_vhost16(vq, headcount); |
cfbdab95 | 690 | if (likely(mergeable) && |
0d79a493 MT |
691 | copy_to_iter(&num_buffers, sizeof num_buffers, |
692 | &fixup) != sizeof num_buffers) { | |
8dd014ad DS |
693 | vq_err(vq, "Failed num_buffers write"); |
694 | vhost_discard_vq_desc(vq, headcount); | |
695 | break; | |
696 | } | |
697 | vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, | |
698 | headcount); | |
699 | if (unlikely(vq_log)) | |
700 | vhost_log_write(vq, vq_log, log, vhost_len); | |
701 | total_len += vhost_len; | |
702 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { | |
703 | vhost_poll_queue(&vq->poll); | |
704 | break; | |
705 | } | |
706 | } | |
2e26af79 | 707 | out: |
8dd014ad | 708 | mutex_unlock(&vq->mutex); |
8dd014ad DS |
709 | } |
710 | ||
c23f3445 | 711 | static void handle_tx_kick(struct vhost_work *work) |
3a4d5c94 | 712 | { |
c23f3445 TH |
713 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
714 | poll.work); | |
715 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
716 | ||
3a4d5c94 MT |
717 | handle_tx(net); |
718 | } | |
719 | ||
c23f3445 | 720 | static void handle_rx_kick(struct vhost_work *work) |
3a4d5c94 | 721 | { |
c23f3445 TH |
722 | struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
723 | poll.work); | |
724 | struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); | |
725 | ||
3a4d5c94 MT |
726 | handle_rx(net); |
727 | } | |
728 | ||
c23f3445 | 729 | static void handle_tx_net(struct vhost_work *work) |
3a4d5c94 | 730 | { |
c23f3445 TH |
731 | struct vhost_net *net = container_of(work, struct vhost_net, |
732 | poll[VHOST_NET_VQ_TX].work); | |
3a4d5c94 MT |
733 | handle_tx(net); |
734 | } | |
735 | ||
c23f3445 | 736 | static void handle_rx_net(struct vhost_work *work) |
3a4d5c94 | 737 | { |
c23f3445 TH |
738 | struct vhost_net *net = container_of(work, struct vhost_net, |
739 | poll[VHOST_NET_VQ_RX].work); | |
3a4d5c94 MT |
740 | handle_rx(net); |
741 | } | |
742 | ||
743 | static int vhost_net_open(struct inode *inode, struct file *f) | |
744 | { | |
23cc5a99 | 745 | struct vhost_net *n; |
c23f3445 | 746 | struct vhost_dev *dev; |
3ab2e420 | 747 | struct vhost_virtqueue **vqs; |
59566b6e | 748 | int i; |
c23f3445 | 749 | |
23cc5a99 MT |
750 | n = kmalloc(sizeof *n, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); |
751 | if (!n) { | |
752 | n = vmalloc(sizeof *n); | |
753 | if (!n) | |
754 | return -ENOMEM; | |
755 | } | |
3ab2e420 AH |
756 | vqs = kmalloc(VHOST_NET_VQ_MAX * sizeof(*vqs), GFP_KERNEL); |
757 | if (!vqs) { | |
d04257b0 | 758 | kvfree(n); |
3ab2e420 AH |
759 | return -ENOMEM; |
760 | } | |
c23f3445 TH |
761 | |
762 | dev = &n->dev; | |
3ab2e420 AH |
763 | vqs[VHOST_NET_VQ_TX] = &n->vqs[VHOST_NET_VQ_TX].vq; |
764 | vqs[VHOST_NET_VQ_RX] = &n->vqs[VHOST_NET_VQ_RX].vq; | |
765 | n->vqs[VHOST_NET_VQ_TX].vq.handle_kick = handle_tx_kick; | |
766 | n->vqs[VHOST_NET_VQ_RX].vq.handle_kick = handle_rx_kick; | |
2839400f AH |
767 | for (i = 0; i < VHOST_NET_VQ_MAX; i++) { |
768 | n->vqs[i].ubufs = NULL; | |
769 | n->vqs[i].ubuf_info = NULL; | |
770 | n->vqs[i].upend_idx = 0; | |
771 | n->vqs[i].done_idx = 0; | |
81f95a55 MT |
772 | n->vqs[i].vhost_hlen = 0; |
773 | n->vqs[i].sock_hlen = 0; | |
2839400f | 774 | } |
59566b6e | 775 | vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX); |
3a4d5c94 | 776 | |
c23f3445 TH |
777 | vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); |
778 | vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); | |
3a4d5c94 MT |
779 | |
780 | f->private_data = n; | |
781 | ||
782 | return 0; | |
783 | } | |
784 | ||
785 | static void vhost_net_disable_vq(struct vhost_net *n, | |
786 | struct vhost_virtqueue *vq) | |
787 | { | |
3ab2e420 AH |
788 | struct vhost_net_virtqueue *nvq = |
789 | container_of(vq, struct vhost_net_virtqueue, vq); | |
790 | struct vhost_poll *poll = n->poll + (nvq - n->vqs); | |
3a4d5c94 MT |
791 | if (!vq->private_data) |
792 | return; | |
70181d51 | 793 | vhost_poll_stop(poll); |
3a4d5c94 MT |
794 | } |
795 | ||
2b8b328b | 796 | static int vhost_net_enable_vq(struct vhost_net *n, |
3a4d5c94 MT |
797 | struct vhost_virtqueue *vq) |
798 | { | |
3ab2e420 AH |
799 | struct vhost_net_virtqueue *nvq = |
800 | container_of(vq, struct vhost_net_virtqueue, vq); | |
801 | struct vhost_poll *poll = n->poll + (nvq - n->vqs); | |
28457ee6 AB |
802 | struct socket *sock; |
803 | ||
22fa90c7 | 804 | sock = vq->private_data; |
3a4d5c94 | 805 | if (!sock) |
2b8b328b | 806 | return 0; |
2b8b328b | 807 | |
70181d51 | 808 | return vhost_poll_start(poll, sock->file); |
3a4d5c94 MT |
809 | } |
810 | ||
811 | static struct socket *vhost_net_stop_vq(struct vhost_net *n, | |
812 | struct vhost_virtqueue *vq) | |
813 | { | |
814 | struct socket *sock; | |
815 | ||
816 | mutex_lock(&vq->mutex); | |
22fa90c7 | 817 | sock = vq->private_data; |
3a4d5c94 | 818 | vhost_net_disable_vq(n, vq); |
22fa90c7 | 819 | vq->private_data = NULL; |
3a4d5c94 MT |
820 | mutex_unlock(&vq->mutex); |
821 | return sock; | |
822 | } | |
823 | ||
824 | static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, | |
825 | struct socket **rx_sock) | |
826 | { | |
3ab2e420 AH |
827 | *tx_sock = vhost_net_stop_vq(n, &n->vqs[VHOST_NET_VQ_TX].vq); |
828 | *rx_sock = vhost_net_stop_vq(n, &n->vqs[VHOST_NET_VQ_RX].vq); | |
3a4d5c94 MT |
829 | } |
830 | ||
831 | static void vhost_net_flush_vq(struct vhost_net *n, int index) | |
832 | { | |
833 | vhost_poll_flush(n->poll + index); | |
3ab2e420 | 834 | vhost_poll_flush(&n->vqs[index].vq.poll); |
3a4d5c94 MT |
835 | } |
836 | ||
837 | static void vhost_net_flush(struct vhost_net *n) | |
838 | { | |
839 | vhost_net_flush_vq(n, VHOST_NET_VQ_TX); | |
840 | vhost_net_flush_vq(n, VHOST_NET_VQ_RX); | |
2839400f | 841 | if (n->vqs[VHOST_NET_VQ_TX].ubufs) { |
3ab2e420 | 842 | mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 843 | n->tx_flush = true; |
3ab2e420 | 844 | mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 845 | /* Wait for all lower device DMAs done. */ |
fe729a57 | 846 | vhost_net_ubuf_put_and_wait(n->vqs[VHOST_NET_VQ_TX].ubufs); |
3ab2e420 | 847 | mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 848 | n->tx_flush = false; |
0ad8b480 | 849 | atomic_set(&n->vqs[VHOST_NET_VQ_TX].ubufs->refcount, 1); |
3ab2e420 | 850 | mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); |
1280c27f | 851 | } |
3a4d5c94 MT |
852 | } |
853 | ||
854 | static int vhost_net_release(struct inode *inode, struct file *f) | |
855 | { | |
856 | struct vhost_net *n = f->private_data; | |
857 | struct socket *tx_sock; | |
858 | struct socket *rx_sock; | |
859 | ||
860 | vhost_net_stop(n, &tx_sock, &rx_sock); | |
861 | vhost_net_flush(n); | |
b211616d | 862 | vhost_dev_stop(&n->dev); |
ea5d4046 | 863 | vhost_dev_cleanup(&n->dev, false); |
81f95a55 | 864 | vhost_net_vq_reset(n); |
3a4d5c94 | 865 | if (tx_sock) |
09aaacf0 | 866 | sockfd_put(tx_sock); |
3a4d5c94 | 867 | if (rx_sock) |
09aaacf0 | 868 | sockfd_put(rx_sock); |
b0c057ca MT |
869 | /* Make sure no callbacks are outstanding */ |
870 | synchronize_rcu_bh(); | |
3a4d5c94 MT |
871 | /* We do an extra flush before freeing memory, |
872 | * since jobs can re-queue themselves. */ | |
873 | vhost_net_flush(n); | |
3ab2e420 | 874 | kfree(n->dev.vqs); |
d04257b0 | 875 | kvfree(n); |
3a4d5c94 MT |
876 | return 0; |
877 | } | |
878 | ||
879 | static struct socket *get_raw_socket(int fd) | |
880 | { | |
881 | struct { | |
882 | struct sockaddr_ll sa; | |
883 | char buf[MAX_ADDR_LEN]; | |
884 | } uaddr; | |
885 | int uaddr_len = sizeof uaddr, r; | |
886 | struct socket *sock = sockfd_lookup(fd, &r); | |
d47effe1 | 887 | |
3a4d5c94 MT |
888 | if (!sock) |
889 | return ERR_PTR(-ENOTSOCK); | |
890 | ||
891 | /* Parameter checking */ | |
892 | if (sock->sk->sk_type != SOCK_RAW) { | |
893 | r = -ESOCKTNOSUPPORT; | |
894 | goto err; | |
895 | } | |
896 | ||
897 | r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, | |
898 | &uaddr_len, 0); | |
899 | if (r) | |
900 | goto err; | |
901 | ||
902 | if (uaddr.sa.sll_family != AF_PACKET) { | |
903 | r = -EPFNOSUPPORT; | |
904 | goto err; | |
905 | } | |
906 | return sock; | |
907 | err: | |
09aaacf0 | 908 | sockfd_put(sock); |
3a4d5c94 MT |
909 | return ERR_PTR(r); |
910 | } | |
911 | ||
501c774c | 912 | static struct socket *get_tap_socket(int fd) |
3a4d5c94 MT |
913 | { |
914 | struct file *file = fget(fd); | |
915 | struct socket *sock; | |
d47effe1 | 916 | |
3a4d5c94 MT |
917 | if (!file) |
918 | return ERR_PTR(-EBADF); | |
919 | sock = tun_get_socket(file); | |
501c774c AB |
920 | if (!IS_ERR(sock)) |
921 | return sock; | |
922 | sock = macvtap_get_socket(file); | |
3a4d5c94 MT |
923 | if (IS_ERR(sock)) |
924 | fput(file); | |
925 | return sock; | |
926 | } | |
927 | ||
928 | static struct socket *get_socket(int fd) | |
929 | { | |
930 | struct socket *sock; | |
d47effe1 | 931 | |
3a4d5c94 MT |
932 | /* special case to disable backend */ |
933 | if (fd == -1) | |
934 | return NULL; | |
935 | sock = get_raw_socket(fd); | |
936 | if (!IS_ERR(sock)) | |
937 | return sock; | |
501c774c | 938 | sock = get_tap_socket(fd); |
3a4d5c94 MT |
939 | if (!IS_ERR(sock)) |
940 | return sock; | |
941 | return ERR_PTR(-ENOTSOCK); | |
942 | } | |
943 | ||
944 | static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) | |
945 | { | |
946 | struct socket *sock, *oldsock; | |
947 | struct vhost_virtqueue *vq; | |
2839400f | 948 | struct vhost_net_virtqueue *nvq; |
fe729a57 | 949 | struct vhost_net_ubuf_ref *ubufs, *oldubufs = NULL; |
3a4d5c94 MT |
950 | int r; |
951 | ||
952 | mutex_lock(&n->dev.mutex); | |
953 | r = vhost_dev_check_owner(&n->dev); | |
954 | if (r) | |
955 | goto err; | |
956 | ||
957 | if (index >= VHOST_NET_VQ_MAX) { | |
958 | r = -ENOBUFS; | |
959 | goto err; | |
960 | } | |
3ab2e420 | 961 | vq = &n->vqs[index].vq; |
2839400f | 962 | nvq = &n->vqs[index]; |
3a4d5c94 MT |
963 | mutex_lock(&vq->mutex); |
964 | ||
965 | /* Verify that ring has been setup correctly. */ | |
966 | if (!vhost_vq_access_ok(vq)) { | |
967 | r = -EFAULT; | |
1dace8c8 | 968 | goto err_vq; |
3a4d5c94 MT |
969 | } |
970 | sock = get_socket(fd); | |
971 | if (IS_ERR(sock)) { | |
972 | r = PTR_ERR(sock); | |
1dace8c8 | 973 | goto err_vq; |
3a4d5c94 MT |
974 | } |
975 | ||
976 | /* start polling new socket */ | |
22fa90c7 | 977 | oldsock = vq->private_data; |
11fe8839 | 978 | if (sock != oldsock) { |
fe729a57 AH |
979 | ubufs = vhost_net_ubuf_alloc(vq, |
980 | sock && vhost_sock_zcopy(sock)); | |
bab632d6 MT |
981 | if (IS_ERR(ubufs)) { |
982 | r = PTR_ERR(ubufs); | |
983 | goto err_ubufs; | |
984 | } | |
692a998b | 985 | |
d47effe1 | 986 | vhost_net_disable_vq(n, vq); |
22fa90c7 | 987 | vq->private_data = sock; |
80f7d030 | 988 | r = vhost_vq_init_access(vq); |
f59281da | 989 | if (r) |
692a998b | 990 | goto err_used; |
2b8b328b JW |
991 | r = vhost_net_enable_vq(n, vq); |
992 | if (r) | |
993 | goto err_used; | |
692a998b | 994 | |
2839400f AH |
995 | oldubufs = nvq->ubufs; |
996 | nvq->ubufs = ubufs; | |
64e9a9b8 MT |
997 | |
998 | n->tx_packets = 0; | |
999 | n->tx_zcopy_err = 0; | |
1280c27f | 1000 | n->tx_flush = false; |
dd1f4078 | 1001 | } |
3a4d5c94 | 1002 | |
1680e906 MT |
1003 | mutex_unlock(&vq->mutex); |
1004 | ||
c047e5f3 | 1005 | if (oldubufs) { |
c38e39c3 | 1006 | vhost_net_ubuf_put_wait_and_free(oldubufs); |
c047e5f3 | 1007 | mutex_lock(&vq->mutex); |
eaae8132 | 1008 | vhost_zerocopy_signal_used(n, vq); |
c047e5f3 MT |
1009 | mutex_unlock(&vq->mutex); |
1010 | } | |
bab632d6 | 1011 | |
3a4d5c94 MT |
1012 | if (oldsock) { |
1013 | vhost_net_flush_vq(n, index); | |
09aaacf0 | 1014 | sockfd_put(oldsock); |
3a4d5c94 | 1015 | } |
1dace8c8 | 1016 | |
1680e906 MT |
1017 | mutex_unlock(&n->dev.mutex); |
1018 | return 0; | |
1019 | ||
692a998b | 1020 | err_used: |
22fa90c7 | 1021 | vq->private_data = oldsock; |
692a998b JW |
1022 | vhost_net_enable_vq(n, vq); |
1023 | if (ubufs) | |
c38e39c3 | 1024 | vhost_net_ubuf_put_wait_and_free(ubufs); |
bab632d6 | 1025 | err_ubufs: |
09aaacf0 | 1026 | sockfd_put(sock); |
1dace8c8 JD |
1027 | err_vq: |
1028 | mutex_unlock(&vq->mutex); | |
3a4d5c94 MT |
1029 | err: |
1030 | mutex_unlock(&n->dev.mutex); | |
1031 | return r; | |
1032 | } | |
1033 | ||
1034 | static long vhost_net_reset_owner(struct vhost_net *n) | |
1035 | { | |
1036 | struct socket *tx_sock = NULL; | |
1037 | struct socket *rx_sock = NULL; | |
1038 | long err; | |
150b9e51 | 1039 | struct vhost_memory *memory; |
d47effe1 | 1040 | |
3a4d5c94 MT |
1041 | mutex_lock(&n->dev.mutex); |
1042 | err = vhost_dev_check_owner(&n->dev); | |
1043 | if (err) | |
1044 | goto done; | |
150b9e51 MT |
1045 | memory = vhost_dev_reset_owner_prepare(); |
1046 | if (!memory) { | |
1047 | err = -ENOMEM; | |
1048 | goto done; | |
1049 | } | |
3a4d5c94 MT |
1050 | vhost_net_stop(n, &tx_sock, &rx_sock); |
1051 | vhost_net_flush(n); | |
150b9e51 | 1052 | vhost_dev_reset_owner(&n->dev, memory); |
81f95a55 | 1053 | vhost_net_vq_reset(n); |
3a4d5c94 MT |
1054 | done: |
1055 | mutex_unlock(&n->dev.mutex); | |
1056 | if (tx_sock) | |
09aaacf0 | 1057 | sockfd_put(tx_sock); |
3a4d5c94 | 1058 | if (rx_sock) |
09aaacf0 | 1059 | sockfd_put(rx_sock); |
3a4d5c94 MT |
1060 | return err; |
1061 | } | |
1062 | ||
1063 | static int vhost_net_set_features(struct vhost_net *n, u64 features) | |
1064 | { | |
8dd014ad | 1065 | size_t vhost_hlen, sock_hlen, hdr_len; |
3a4d5c94 | 1066 | int i; |
8dd014ad | 1067 | |
e4fca7d6 MT |
1068 | hdr_len = (features & ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | |
1069 | (1ULL << VIRTIO_F_VERSION_1))) ? | |
8dd014ad DS |
1070 | sizeof(struct virtio_net_hdr_mrg_rxbuf) : |
1071 | sizeof(struct virtio_net_hdr); | |
1072 | if (features & (1 << VHOST_NET_F_VIRTIO_NET_HDR)) { | |
1073 | /* vhost provides vnet_hdr */ | |
1074 | vhost_hlen = hdr_len; | |
1075 | sock_hlen = 0; | |
1076 | } else { | |
1077 | /* socket provides vnet_hdr */ | |
1078 | vhost_hlen = 0; | |
1079 | sock_hlen = hdr_len; | |
1080 | } | |
3a4d5c94 MT |
1081 | mutex_lock(&n->dev.mutex); |
1082 | if ((features & (1 << VHOST_F_LOG_ALL)) && | |
1083 | !vhost_log_access_ok(&n->dev)) { | |
1084 | mutex_unlock(&n->dev.mutex); | |
1085 | return -EFAULT; | |
1086 | } | |
3a4d5c94 | 1087 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { |
3ab2e420 | 1088 | mutex_lock(&n->vqs[i].vq.mutex); |
ea16c514 | 1089 | n->vqs[i].vq.acked_features = features; |
81f95a55 MT |
1090 | n->vqs[i].vhost_hlen = vhost_hlen; |
1091 | n->vqs[i].sock_hlen = sock_hlen; | |
3ab2e420 | 1092 | mutex_unlock(&n->vqs[i].vq.mutex); |
3a4d5c94 | 1093 | } |
3a4d5c94 MT |
1094 | mutex_unlock(&n->dev.mutex); |
1095 | return 0; | |
1096 | } | |
1097 | ||
b1ad8496 AH |
1098 | static long vhost_net_set_owner(struct vhost_net *n) |
1099 | { | |
1100 | int r; | |
1101 | ||
1102 | mutex_lock(&n->dev.mutex); | |
05c05351 MT |
1103 | if (vhost_dev_has_owner(&n->dev)) { |
1104 | r = -EBUSY; | |
1105 | goto out; | |
1106 | } | |
b1ad8496 AH |
1107 | r = vhost_net_set_ubuf_info(n); |
1108 | if (r) | |
1109 | goto out; | |
1110 | r = vhost_dev_set_owner(&n->dev); | |
1111 | if (r) | |
1112 | vhost_net_clear_ubuf_info(n); | |
1113 | vhost_net_flush(n); | |
1114 | out: | |
1115 | mutex_unlock(&n->dev.mutex); | |
1116 | return r; | |
1117 | } | |
1118 | ||
3a4d5c94 MT |
1119 | static long vhost_net_ioctl(struct file *f, unsigned int ioctl, |
1120 | unsigned long arg) | |
1121 | { | |
1122 | struct vhost_net *n = f->private_data; | |
1123 | void __user *argp = (void __user *)arg; | |
1124 | u64 __user *featurep = argp; | |
1125 | struct vhost_vring_file backend; | |
1126 | u64 features; | |
1127 | int r; | |
d47effe1 | 1128 | |
3a4d5c94 MT |
1129 | switch (ioctl) { |
1130 | case VHOST_NET_SET_BACKEND: | |
d3553a52 TY |
1131 | if (copy_from_user(&backend, argp, sizeof backend)) |
1132 | return -EFAULT; | |
3a4d5c94 MT |
1133 | return vhost_net_set_backend(n, backend.index, backend.fd); |
1134 | case VHOST_GET_FEATURES: | |
0dd05a3b | 1135 | features = VHOST_NET_FEATURES; |
d3553a52 TY |
1136 | if (copy_to_user(featurep, &features, sizeof features)) |
1137 | return -EFAULT; | |
1138 | return 0; | |
3a4d5c94 | 1139 | case VHOST_SET_FEATURES: |
d3553a52 TY |
1140 | if (copy_from_user(&features, featurep, sizeof features)) |
1141 | return -EFAULT; | |
0dd05a3b | 1142 | if (features & ~VHOST_NET_FEATURES) |
3a4d5c94 MT |
1143 | return -EOPNOTSUPP; |
1144 | return vhost_net_set_features(n, features); | |
1145 | case VHOST_RESET_OWNER: | |
1146 | return vhost_net_reset_owner(n); | |
b1ad8496 AH |
1147 | case VHOST_SET_OWNER: |
1148 | return vhost_net_set_owner(n); | |
3a4d5c94 MT |
1149 | default: |
1150 | mutex_lock(&n->dev.mutex); | |
935cdee7 MT |
1151 | r = vhost_dev_ioctl(&n->dev, ioctl, argp); |
1152 | if (r == -ENOIOCTLCMD) | |
1153 | r = vhost_vring_ioctl(&n->dev, ioctl, argp); | |
1154 | else | |
1155 | vhost_net_flush(n); | |
3a4d5c94 MT |
1156 | mutex_unlock(&n->dev.mutex); |
1157 | return r; | |
1158 | } | |
1159 | } | |
1160 | ||
1161 | #ifdef CONFIG_COMPAT | |
1162 | static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, | |
1163 | unsigned long arg) | |
1164 | { | |
1165 | return vhost_net_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); | |
1166 | } | |
1167 | #endif | |
1168 | ||
373a83a6 | 1169 | static const struct file_operations vhost_net_fops = { |
3a4d5c94 MT |
1170 | .owner = THIS_MODULE, |
1171 | .release = vhost_net_release, | |
1172 | .unlocked_ioctl = vhost_net_ioctl, | |
1173 | #ifdef CONFIG_COMPAT | |
1174 | .compat_ioctl = vhost_net_compat_ioctl, | |
1175 | #endif | |
1176 | .open = vhost_net_open, | |
6038f373 | 1177 | .llseek = noop_llseek, |
3a4d5c94 MT |
1178 | }; |
1179 | ||
1180 | static struct miscdevice vhost_net_misc = { | |
7c7c7f01 | 1181 | .minor = VHOST_NET_MINOR, |
1182 | .name = "vhost-net", | |
1183 | .fops = &vhost_net_fops, | |
3a4d5c94 MT |
1184 | }; |
1185 | ||
a8d3782f | 1186 | static int vhost_net_init(void) |
3a4d5c94 | 1187 | { |
bab632d6 | 1188 | if (experimental_zcopytx) |
fe729a57 | 1189 | vhost_net_enable_zcopy(VHOST_NET_VQ_TX); |
c23f3445 | 1190 | return misc_register(&vhost_net_misc); |
3a4d5c94 MT |
1191 | } |
1192 | module_init(vhost_net_init); | |
1193 | ||
a8d3782f | 1194 | static void vhost_net_exit(void) |
3a4d5c94 MT |
1195 | { |
1196 | misc_deregister(&vhost_net_misc); | |
3a4d5c94 MT |
1197 | } |
1198 | module_exit(vhost_net_exit); | |
1199 | ||
1200 | MODULE_VERSION("0.0.1"); | |
1201 | MODULE_LICENSE("GPL v2"); | |
1202 | MODULE_AUTHOR("Michael S. Tsirkin"); | |
1203 | MODULE_DESCRIPTION("Host kernel accelerator for virtio net"); | |
7c7c7f01 | 1204 | MODULE_ALIAS_MISCDEV(VHOST_NET_MINOR); |
1205 | MODULE_ALIAS("devname:vhost-net"); |