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vsock: add 'transport' member in the struct vsock_sock
[linux-2.6-block.git] / net / vmw_vsock / virtio_transport_common.c
CommitLineData
7a338472 1// SPDX-License-Identifier: GPL-2.0-only
06a8fc78
AH		 2/*
3 * common code for virtio vsock
4 *
5 * Copyright (C) 2013-2015 Red Hat, Inc.
6 * Author: Asias He <asias@redhat.com>
7 * Stefan Hajnoczi <stefanha@redhat.com>
06a8fc78
AH		 8 */
9#include <linux/spinlock.h>
10#include <linux/module.h>
174cd4b1 11#include <linux/sched/signal.h>
06a8fc78
AH		 12#include <linux/ctype.h>
13#include <linux/list.h>
14#include <linux/virtio.h>
15#include <linux/virtio_ids.h>
16#include <linux/virtio_config.h>
17#include <linux/virtio_vsock.h>
82dfb540 18#include <uapi/linux/vsockmon.h>
06a8fc78
AH		 19
20#include <net/sock.h>
21#include <net/af_vsock.h>
22
23#define CREATE_TRACE_POINTS
24#include <trace/events/vsock_virtio_transport_common.h>
25
26/* How long to wait for graceful shutdown of a connection */
27#define VSOCK_CLOSE_TIMEOUT (8 * HZ)
28
473c7391
SG		 29/* Threshold for detecting small packets to copy */
30#define GOOD_COPY_LEN 128
31
06a8fc78
AH		 32static const struct virtio_transport *virtio_transport_get_ops(void)
33{
34 const struct vsock_transport *t = vsock_core_get_transport();
35
36 return container_of(t, struct virtio_transport, transport);
37}
38
819483d8 39static struct virtio_vsock_pkt *
06a8fc78
AH		 40virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
41 size_t len,
42 u32 src_cid,
43 u32 src_port,
44 u32 dst_cid,
45 u32 dst_port)
46{
47 struct virtio_vsock_pkt *pkt;
48 int err;
49
50 pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
51 if (!pkt)
52 return NULL;
53
54 pkt->hdr.type = cpu_to_le16(info->type);
55 pkt->hdr.op = cpu_to_le16(info->op);
56 pkt->hdr.src_cid = cpu_to_le64(src_cid);
57 pkt->hdr.dst_cid = cpu_to_le64(dst_cid);
58 pkt->hdr.src_port = cpu_to_le32(src_port);
59 pkt->hdr.dst_port = cpu_to_le32(dst_port);
60 pkt->hdr.flags = cpu_to_le32(info->flags);
61 pkt->len = len;
62 pkt->hdr.len = cpu_to_le32(len);
63 pkt->reply = info->reply;
36d277ba 64 pkt->vsk = info->vsk;
06a8fc78
AH		 65
66 if (info->msg && len > 0) {
67 pkt->buf = kmalloc(len, GFP_KERNEL);
68 if (!pkt->buf)
69 goto out_pkt;
473c7391
SG		 70
71 pkt->buf_len = len;
72
06a8fc78
AH		 73 err = memcpy_from_msg(pkt->buf, info->msg, len);
74 if (err)
75 goto out;
76 }
77
78 trace_virtio_transport_alloc_pkt(src_cid, src_port,
79 dst_cid, dst_port,
80 len,
81 info->type,
82 info->op,
83 info->flags);
84
85 return pkt;
86
87out:
88 kfree(pkt->buf);
89out_pkt:
90 kfree(pkt);
91 return NULL;
92}
06a8fc78 93
82dfb540
GG		 94/* Packet capture */
95static struct sk_buff *virtio_transport_build_skb(void *opaque)
96{
97 struct virtio_vsock_pkt *pkt = opaque;
82dfb540
GG		 98 struct af_vsockmon_hdr *hdr;
99 struct sk_buff *skb;
6dbd3e66
SG		 100 size_t payload_len;
101 void *payload_buf;
82dfb540 102
6dbd3e66
SG		 103 /* A packet could be split to fit the RX buffer, so we can retrieve
104 * the payload length from the header and the buffer pointer taking
105 * care of the offset in the original packet.
106 */
107 payload_len = le32_to_cpu(pkt->hdr.len);
108 payload_buf = pkt->buf + pkt->off;
109
110 skb = alloc_skb(sizeof(*hdr) + sizeof(pkt->hdr) + payload_len,
82dfb540
GG		 111 GFP_ATOMIC);
112 if (!skb)
113 return NULL;
114
4df864c1 115 hdr = skb_put(skb, sizeof(*hdr));
82dfb540
GG		 116
117 /* pkt->hdr is little-endian so no need to byteswap here */
118 hdr->src_cid = pkt->hdr.src_cid;
119 hdr->src_port = pkt->hdr.src_port;
120 hdr->dst_cid = pkt->hdr.dst_cid;
121 hdr->dst_port = pkt->hdr.dst_port;
122
123 hdr->transport = cpu_to_le16(AF_VSOCK_TRANSPORT_VIRTIO);
124 hdr->len = cpu_to_le16(sizeof(pkt->hdr));
125 memset(hdr->reserved, 0, sizeof(hdr->reserved));
126
127 switch (le16_to_cpu(pkt->hdr.op)) {
128 case VIRTIO_VSOCK_OP_REQUEST:
129 case VIRTIO_VSOCK_OP_RESPONSE:
130 hdr->op = cpu_to_le16(AF_VSOCK_OP_CONNECT);
131 break;
132 case VIRTIO_VSOCK_OP_RST:
133 case VIRTIO_VSOCK_OP_SHUTDOWN:
134 hdr->op = cpu_to_le16(AF_VSOCK_OP_DISCONNECT);
135 break;
136 case VIRTIO_VSOCK_OP_RW:
137 hdr->op = cpu_to_le16(AF_VSOCK_OP_PAYLOAD);
138 break;
139 case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
140 case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
141 hdr->op = cpu_to_le16(AF_VSOCK_OP_CONTROL);
142 break;
143 default:
144 hdr->op = cpu_to_le16(AF_VSOCK_OP_UNKNOWN);
145 break;
146 }
147
b952f4df 148 skb_put_data(skb, &pkt->hdr, sizeof(pkt->hdr));
82dfb540 149
6dbd3e66
SG		 150 if (payload_len) {
151 skb_put_data(skb, payload_buf, payload_len);
82dfb540
GG		 152 }
153
154 return skb;
155}
156
157void virtio_transport_deliver_tap_pkt(struct virtio_vsock_pkt *pkt)
158{
159 vsock_deliver_tap(virtio_transport_build_skb, pkt);
160}
161EXPORT_SYMBOL_GPL(virtio_transport_deliver_tap_pkt);
162
06a8fc78
AH		 163static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
164 struct virtio_vsock_pkt_info *info)
165{
166 u32 src_cid, src_port, dst_cid, dst_port;
167 struct virtio_vsock_sock *vvs;
168 struct virtio_vsock_pkt *pkt;
169 u32 pkt_len = info->pkt_len;
170
db205c76 171 src_cid = virtio_transport_get_ops()->transport.get_local_cid();
06a8fc78
AH		 172 src_port = vsk->local_addr.svm_port;
173 if (!info->remote_cid) {
174 dst_cid = vsk->remote_addr.svm_cid;
175 dst_port = vsk->remote_addr.svm_port;
176 } else {
177 dst_cid = info->remote_cid;
178 dst_port = info->remote_port;
179 }
180
181 vvs = vsk->trans;
182
183 /* we can send less than pkt_len bytes */
0038ff35
SG		 184 if (pkt_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE)
185 pkt_len = VIRTIO_VSOCK_MAX_PKT_BUF_SIZE;
06a8fc78
AH		 186
187 /* virtio_transport_get_credit might return less than pkt_len credit */
188 pkt_len = virtio_transport_get_credit(vvs, pkt_len);
189
190 /* Do not send zero length OP_RW pkt */
191 if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
192 return pkt_len;
193
194 pkt = virtio_transport_alloc_pkt(info, pkt_len,
195 src_cid, src_port,
196 dst_cid, dst_port);
197 if (!pkt) {
198 virtio_transport_put_credit(vvs, pkt_len);
199 return -ENOMEM;
200 }
201
202 virtio_transport_inc_tx_pkt(vvs, pkt);
203
204 return virtio_transport_get_ops()->send_pkt(pkt);
205}
206
ae6fcfbf 207static bool virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs,
06a8fc78
AH		 208 struct virtio_vsock_pkt *pkt)
209{
ae6fcfbf
SG		 210 if (vvs->rx_bytes + pkt->len > vvs->buf_alloc)
211 return false;
212
06a8fc78 213 vvs->rx_bytes += pkt->len;
ae6fcfbf 214 return true;
06a8fc78
AH		 215}
216
217static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs,
218 struct virtio_vsock_pkt *pkt)
219{
220 vvs->rx_bytes -= pkt->len;
221 vvs->fwd_cnt += pkt->len;
222}
223
224void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt)
225{
9632e9f6 226 spin_lock_bh(&vvs->rx_lock);
b89d882d 227 vvs->last_fwd_cnt = vvs->fwd_cnt;
06a8fc78
AH		 228 pkt->hdr.fwd_cnt = cpu_to_le32(vvs->fwd_cnt);
229 pkt->hdr.buf_alloc = cpu_to_le32(vvs->buf_alloc);
9632e9f6 230 spin_unlock_bh(&vvs->rx_lock);
06a8fc78
AH		 231}
232EXPORT_SYMBOL_GPL(virtio_transport_inc_tx_pkt);
233
234u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 credit)
235{
236 u32 ret;
237
238 spin_lock_bh(&vvs->tx_lock);
239 ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
240 if (ret > credit)
241 ret = credit;
242 vvs->tx_cnt += ret;
243 spin_unlock_bh(&vvs->tx_lock);
244
245 return ret;
246}
247EXPORT_SYMBOL_GPL(virtio_transport_get_credit);
248
249void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit)
250{
251 spin_lock_bh(&vvs->tx_lock);
252 vvs->tx_cnt -= credit;
253 spin_unlock_bh(&vvs->tx_lock);
254}
255EXPORT_SYMBOL_GPL(virtio_transport_put_credit);
256
257static int virtio_transport_send_credit_update(struct vsock_sock *vsk,
258 int type,
259 struct virtio_vsock_hdr *hdr)
260{
261 struct virtio_vsock_pkt_info info = {
262 .op = VIRTIO_VSOCK_OP_CREDIT_UPDATE,
263 .type = type,
36d277ba 264 .vsk = vsk,
06a8fc78
AH		 265 };
266
267 return virtio_transport_send_pkt_info(vsk, &info);
268}
269
a786ab36
MEVL		 270static ssize_t
271virtio_transport_stream_do_peek(struct vsock_sock *vsk,
272 struct msghdr *msg,
273 size_t len)
274{
275 struct virtio_vsock_sock *vvs = vsk->trans;
276 struct virtio_vsock_pkt *pkt;
277 size_t bytes, total = 0, off;
278 int err = -EFAULT;
279
280 spin_lock_bh(&vvs->rx_lock);
281
282 list_for_each_entry(pkt, &vvs->rx_queue, list) {
283 off = pkt->off;
284
285 if (total == len)
286 break;
287
288 while (total < len && off < pkt->len) {
289 bytes = len - total;
290 if (bytes > pkt->len - off)
291 bytes = pkt->len - off;
292
293 /* sk_lock is held by caller so no one else can dequeue.
294 * Unlock rx_lock since memcpy_to_msg() may sleep.
295 */
296 spin_unlock_bh(&vvs->rx_lock);
297
298 err = memcpy_to_msg(msg, pkt->buf + off, bytes);
299 if (err)
300 goto out;
301
302 spin_lock_bh(&vvs->rx_lock);
303
304 total += bytes;
305 off += bytes;
306 }
307 }
308
309 spin_unlock_bh(&vvs->rx_lock);
310
311 return total;
312
313out:
314 if (total)
315 err = total;
316 return err;
317}
318
06a8fc78
AH		 319static ssize_t
320virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
321 struct msghdr *msg,
322 size_t len)
323{
324 struct virtio_vsock_sock *vvs = vsk->trans;
325 struct virtio_vsock_pkt *pkt;
326 size_t bytes, total = 0;
b89d882d 327 u32 free_space;
06a8fc78
AH		 328 int err = -EFAULT;
329
330 spin_lock_bh(&vvs->rx_lock);
331 while (total < len && !list_empty(&vvs->rx_queue)) {
332 pkt = list_first_entry(&vvs->rx_queue,
333 struct virtio_vsock_pkt, list);
334
335 bytes = len - total;
336 if (bytes > pkt->len - pkt->off)
337 bytes = pkt->len - pkt->off;
338
339 /* sk_lock is held by caller so no one else can dequeue.
340 * Unlock rx_lock since memcpy_to_msg() may sleep.
341 */
342 spin_unlock_bh(&vvs->rx_lock);
343
344 err = memcpy_to_msg(msg, pkt->buf + pkt->off, bytes);
345 if (err)
346 goto out;
347
348 spin_lock_bh(&vvs->rx_lock);
349
350 total += bytes;
351 pkt->off += bytes;
352 if (pkt->off == pkt->len) {
353 virtio_transport_dec_rx_pkt(vvs, pkt);
354 list_del(&pkt->list);
355 virtio_transport_free_pkt(pkt);
356 }
357 }
b89d882d
SG		 358
359 free_space = vvs->buf_alloc - (vvs->fwd_cnt - vvs->last_fwd_cnt);
360
06a8fc78
AH		 361 spin_unlock_bh(&vvs->rx_lock);
362
f4d7c8e3
MT		 363 /* To reduce the number of credit update messages,
364 * don't update credits as long as lots of space is available.
365 * Note: the limit chosen here is arbitrary. Setting the limit
366 * too high causes extra messages. Too low causes transmitter
367 * stalls. As stalls are in theory more expensive than extra
368 * messages, we set the limit to a high value. TODO: experiment
369 * with different values.
b89d882d
SG		 370 */
371 if (free_space < VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
372 virtio_transport_send_credit_update(vsk,
373 VIRTIO_VSOCK_TYPE_STREAM,
374 NULL);
375 }
06a8fc78
AH		 376
377 return total;
378
379out:
380 if (total)
381 err = total;
382 return err;
383}
384
385ssize_t
386virtio_transport_stream_dequeue(struct vsock_sock *vsk,
387 struct msghdr *msg,
388 size_t len, int flags)
389{
390 if (flags & MSG_PEEK)
a786ab36
MEVL		 391 return virtio_transport_stream_do_peek(vsk, msg, len);
392 else
393 return virtio_transport_stream_do_dequeue(vsk, msg, len);
06a8fc78
AH		 394}
395EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue);
396
397int
398virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
399 struct msghdr *msg,
400 size_t len, int flags)
401{
402 return -EOPNOTSUPP;
403}
404EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue);
405
406s64 virtio_transport_stream_has_data(struct vsock_sock *vsk)
407{
408 struct virtio_vsock_sock *vvs = vsk->trans;
409 s64 bytes;
410
411 spin_lock_bh(&vvs->rx_lock);
412 bytes = vvs->rx_bytes;
413 spin_unlock_bh(&vvs->rx_lock);
414
415 return bytes;
416}
417EXPORT_SYMBOL_GPL(virtio_transport_stream_has_data);
418
419static s64 virtio_transport_has_space(struct vsock_sock *vsk)
420{
421 struct virtio_vsock_sock *vvs = vsk->trans;
422 s64 bytes;
423
424 bytes = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
425 if (bytes < 0)
426 bytes = 0;
427
428 return bytes;
429}
430
431s64 virtio_transport_stream_has_space(struct vsock_sock *vsk)
432{
433 struct virtio_vsock_sock *vvs = vsk->trans;
434 s64 bytes;
435
436 spin_lock_bh(&vvs->tx_lock);
437 bytes = virtio_transport_has_space(vsk);
438 spin_unlock_bh(&vvs->tx_lock);
439
440 return bytes;
441}
442EXPORT_SYMBOL_GPL(virtio_transport_stream_has_space);
443
444int virtio_transport_do_socket_init(struct vsock_sock *vsk,
445 struct vsock_sock *psk)
446{
447 struct virtio_vsock_sock *vvs;
448
449 vvs = kzalloc(sizeof(*vvs), GFP_KERNEL);
450 if (!vvs)
451 return -ENOMEM;
452
453 vsk->trans = vvs;
454 vvs->vsk = vsk;
455 if (psk) {
456 struct virtio_vsock_sock *ptrans = psk->trans;
457
458 vvs->buf_size = ptrans->buf_size;
459 vvs->buf_size_min = ptrans->buf_size_min;
460 vvs->buf_size_max = ptrans->buf_size_max;
461 vvs->peer_buf_alloc = ptrans->peer_buf_alloc;
462 } else {
463 vvs->buf_size = VIRTIO_VSOCK_DEFAULT_BUF_SIZE;
464 vvs->buf_size_min = VIRTIO_VSOCK_DEFAULT_MIN_BUF_SIZE;
465 vvs->buf_size_max = VIRTIO_VSOCK_DEFAULT_MAX_BUF_SIZE;
466 }
467
468 vvs->buf_alloc = vvs->buf_size;
469
470 spin_lock_init(&vvs->rx_lock);
471 spin_lock_init(&vvs->tx_lock);
472 INIT_LIST_HEAD(&vvs->rx_queue);
473
474 return 0;
475}
476EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
477
478u64 virtio_transport_get_buffer_size(struct vsock_sock *vsk)
479{
480 struct virtio_vsock_sock *vvs = vsk->trans;
481
482 return vvs->buf_size;
483}
484EXPORT_SYMBOL_GPL(virtio_transport_get_buffer_size);
485
486u64 virtio_transport_get_min_buffer_size(struct vsock_sock *vsk)
487{
488 struct virtio_vsock_sock *vvs = vsk->trans;
489
490 return vvs->buf_size_min;
491}
492EXPORT_SYMBOL_GPL(virtio_transport_get_min_buffer_size);
493
494u64 virtio_transport_get_max_buffer_size(struct vsock_sock *vsk)
495{
496 struct virtio_vsock_sock *vvs = vsk->trans;
497
498 return vvs->buf_size_max;
499}
500EXPORT_SYMBOL_GPL(virtio_transport_get_max_buffer_size);
501
502void virtio_transport_set_buffer_size(struct vsock_sock *vsk, u64 val)
503{
504 struct virtio_vsock_sock *vvs = vsk->trans;
505
506 if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
507 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
508 if (val < vvs->buf_size_min)
509 vvs->buf_size_min = val;
510 if (val > vvs->buf_size_max)
511 vvs->buf_size_max = val;
512 vvs->buf_size = val;
513 vvs->buf_alloc = val;
ec3359b6
SG		 514
515 virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
516 NULL);
06a8fc78
AH		 517}
518EXPORT_SYMBOL_GPL(virtio_transport_set_buffer_size);
519
520void virtio_transport_set_min_buffer_size(struct vsock_sock *vsk, u64 val)
521{
522 struct virtio_vsock_sock *vvs = vsk->trans;
523
524 if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
525 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
526 if (val > vvs->buf_size)
527 vvs->buf_size = val;
528 vvs->buf_size_min = val;
529}
530EXPORT_SYMBOL_GPL(virtio_transport_set_min_buffer_size);
531
532void virtio_transport_set_max_buffer_size(struct vsock_sock *vsk, u64 val)
533{
534 struct virtio_vsock_sock *vvs = vsk->trans;
535
536 if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
537 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
538 if (val < vvs->buf_size)
539 vvs->buf_size = val;
540 vvs->buf_size_max = val;
541}
542EXPORT_SYMBOL_GPL(virtio_transport_set_max_buffer_size);
543
544int
545virtio_transport_notify_poll_in(struct vsock_sock *vsk,
546 size_t target,
547 bool *data_ready_now)
548{
549 if (vsock_stream_has_data(vsk))
550 *data_ready_now = true;
551 else
552 *data_ready_now = false;
553
554 return 0;
555}
556EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_in);
557
558int
559virtio_transport_notify_poll_out(struct vsock_sock *vsk,
560 size_t target,
561 bool *space_avail_now)
562{
563 s64 free_space;
564
565 free_space = vsock_stream_has_space(vsk);
566 if (free_space > 0)
567 *space_avail_now = true;
568 else if (free_space == 0)
569 *space_avail_now = false;
570
571 return 0;
572}
573EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_out);
574
575int virtio_transport_notify_recv_init(struct vsock_sock *vsk,
576 size_t target, struct vsock_transport_recv_notify_data *data)
577{
578 return 0;
579}
580EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_init);
581
582int virtio_transport_notify_recv_pre_block(struct vsock_sock *vsk,
583 size_t target, struct vsock_transport_recv_notify_data *data)
584{
585 return 0;
586}
587EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_block);
588
589int virtio_transport_notify_recv_pre_dequeue(struct vsock_sock *vsk,
590 size_t target, struct vsock_transport_recv_notify_data *data)
591{
592 return 0;
593}
594EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_dequeue);
595
596int virtio_transport_notify_recv_post_dequeue(struct vsock_sock *vsk,
597 size_t target, ssize_t copied, bool data_read,
598 struct vsock_transport_recv_notify_data *data)
599{
600 return 0;
601}
602EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_post_dequeue);
603
604int virtio_transport_notify_send_init(struct vsock_sock *vsk,
605 struct vsock_transport_send_notify_data *data)
606{
607 return 0;
608}
609EXPORT_SYMBOL_GPL(virtio_transport_notify_send_init);
610
611int virtio_transport_notify_send_pre_block(struct vsock_sock *vsk,
612 struct vsock_transport_send_notify_data *data)
613{
614 return 0;
615}
616EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_block);
617
618int virtio_transport_notify_send_pre_enqueue(struct vsock_sock *vsk,
619 struct vsock_transport_send_notify_data *data)
620{
621 return 0;
622}
623EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_enqueue);
624
625int virtio_transport_notify_send_post_enqueue(struct vsock_sock *vsk,
626 ssize_t written, struct vsock_transport_send_notify_data *data)
627{
628 return 0;
629}
630EXPORT_SYMBOL_GPL(virtio_transport_notify_send_post_enqueue);
631
632u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk)
633{
634 struct virtio_vsock_sock *vvs = vsk->trans;
635
636 return vvs->buf_size;
637}
638EXPORT_SYMBOL_GPL(virtio_transport_stream_rcvhiwat);
639
640bool virtio_transport_stream_is_active(struct vsock_sock *vsk)
641{
642 return true;
643}
644EXPORT_SYMBOL_GPL(virtio_transport_stream_is_active);
645
646bool virtio_transport_stream_allow(u32 cid, u32 port)
647{
648 return true;
649}
650EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
651
652int virtio_transport_dgram_bind(struct vsock_sock *vsk,
653 struct sockaddr_vm *addr)
654{
655 return -EOPNOTSUPP;
656}
657EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);
658
659bool virtio_transport_dgram_allow(u32 cid, u32 port)
660{
661 return false;
662}
663EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
664
665int virtio_transport_connect(struct vsock_sock *vsk)
666{
667 struct virtio_vsock_pkt_info info = {
668 .op = VIRTIO_VSOCK_OP_REQUEST,
669 .type = VIRTIO_VSOCK_TYPE_STREAM,
36d277ba 670 .vsk = vsk,
06a8fc78
AH		 671 };
672
673 return virtio_transport_send_pkt_info(vsk, &info);
674}
675EXPORT_SYMBOL_GPL(virtio_transport_connect);
676
677int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
678{
679 struct virtio_vsock_pkt_info info = {
680 .op = VIRTIO_VSOCK_OP_SHUTDOWN,
681 .type = VIRTIO_VSOCK_TYPE_STREAM,
682 .flags = (mode & RCV_SHUTDOWN ?
683 VIRTIO_VSOCK_SHUTDOWN_RCV : 0) |
684 (mode & SEND_SHUTDOWN ?
685 VIRTIO_VSOCK_SHUTDOWN_SEND : 0),
36d277ba 686 .vsk = vsk,
06a8fc78
AH		 687 };
688
689 return virtio_transport_send_pkt_info(vsk, &info);
690}
691EXPORT_SYMBOL_GPL(virtio_transport_shutdown);
692
693int
694virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
695 struct sockaddr_vm *remote_addr,
696 struct msghdr *msg,
697 size_t dgram_len)
698{
699 return -EOPNOTSUPP;
700}
701EXPORT_SYMBOL_GPL(virtio_transport_dgram_enqueue);
702
703ssize_t
704virtio_transport_stream_enqueue(struct vsock_sock *vsk,
705 struct msghdr *msg,
706 size_t len)
707{
708 struct virtio_vsock_pkt_info info = {
709 .op = VIRTIO_VSOCK_OP_RW,
710 .type = VIRTIO_VSOCK_TYPE_STREAM,
711 .msg = msg,
712 .pkt_len = len,
36d277ba 713 .vsk = vsk,
06a8fc78
AH		 714 };
715
716 return virtio_transport_send_pkt_info(vsk, &info);
717}
718EXPORT_SYMBOL_GPL(virtio_transport_stream_enqueue);
719
720void virtio_transport_destruct(struct vsock_sock *vsk)
721{
722 struct virtio_vsock_sock *vvs = vsk->trans;
723
724 kfree(vvs);
725}
726EXPORT_SYMBOL_GPL(virtio_transport_destruct);
727
728static int virtio_transport_reset(struct vsock_sock *vsk,
729 struct virtio_vsock_pkt *pkt)
730{
731 struct virtio_vsock_pkt_info info = {
732 .op = VIRTIO_VSOCK_OP_RST,
733 .type = VIRTIO_VSOCK_TYPE_STREAM,
734 .reply = !!pkt,
36d277ba 735 .vsk = vsk,
06a8fc78
AH		 736 };
737
738 /* Send RST only if the original pkt is not a RST pkt */
739 if (pkt && le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
740 return 0;
741
742 return virtio_transport_send_pkt_info(vsk, &info);
743}
744
745/* Normally packets are associated with a socket. There may be no socket if an
746 * attempt was made to connect to a socket that does not exist.
747 */
748static int virtio_transport_reset_no_sock(struct virtio_vsock_pkt *pkt)
749{
4c404ce2
AL		 750 const struct virtio_transport *t;
751 struct virtio_vsock_pkt *reply;
06a8fc78
AH		 752 struct virtio_vsock_pkt_info info = {
753 .op = VIRTIO_VSOCK_OP_RST,
754 .type = le16_to_cpu(pkt->hdr.type),
755 .reply = true,
756 };
757
758 /* Send RST only if the original pkt is not a RST pkt */
759 if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
760 return 0;
761
4c404ce2
AL		 762 reply = virtio_transport_alloc_pkt(&info, 0,
763 le64_to_cpu(pkt->hdr.dst_cid),
764 le32_to_cpu(pkt->hdr.dst_port),
765 le64_to_cpu(pkt->hdr.src_cid),
766 le32_to_cpu(pkt->hdr.src_port));
767 if (!reply)
06a8fc78
AH		 768 return -ENOMEM;
769
4c404ce2
AL		 770 t = virtio_transport_get_ops();
771 if (!t) {
772 virtio_transport_free_pkt(reply);
773 return -ENOTCONN;
774 }
775
776 return t->send_pkt(reply);
06a8fc78
AH		 777}
778
779static void virtio_transport_wait_close(struct sock *sk, long timeout)
780{
781 if (timeout) {
d9dc8b0f
WC		 782 DEFINE_WAIT_FUNC(wait, woken_wake_function);
783
784 add_wait_queue(sk_sleep(sk), &wait);
06a8fc78
AH		 785
786 do {
06a8fc78 787 if (sk_wait_event(sk, &timeout,
d9dc8b0f 788 sock_flag(sk, SOCK_DONE), &wait))
06a8fc78
AH		 789 break;
790 } while (!signal_pending(current) && timeout);
791
d9dc8b0f 792 remove_wait_queue(sk_sleep(sk), &wait);
06a8fc78
AH		 793 }
794}
795
796static void virtio_transport_do_close(struct vsock_sock *vsk,
797 bool cancel_timeout)
798{
799 struct sock *sk = sk_vsock(vsk);
800
801 sock_set_flag(sk, SOCK_DONE);
802 vsk->peer_shutdown = SHUTDOWN_MASK;
803 if (vsock_stream_has_data(vsk) <= 0)
3b4477d2 804 sk->sk_state = TCP_CLOSING;
06a8fc78
AH		 805 sk->sk_state_change(sk);
806
807 if (vsk->close_work_scheduled &&
808 (!cancel_timeout || cancel_delayed_work(&vsk->close_work))) {
809 vsk->close_work_scheduled = false;
810
811 vsock_remove_sock(vsk);
812
813 /* Release refcnt obtained when we scheduled the timeout */
814 sock_put(sk);
815 }
816}
817
818static void virtio_transport_close_timeout(struct work_struct *work)
819{
820 struct vsock_sock *vsk =
821 container_of(work, struct vsock_sock, close_work.work);
822 struct sock *sk = sk_vsock(vsk);
823
824 sock_hold(sk);
825 lock_sock(sk);
826
827 if (!sock_flag(sk, SOCK_DONE)) {
828 (void)virtio_transport_reset(vsk, NULL);
829
830 virtio_transport_do_close(vsk, false);
831 }
832
833 vsk->close_work_scheduled = false;
834
835 release_sock(sk);
836 sock_put(sk);
837}
838
839/* User context, vsk->sk is locked */
840static bool virtio_transport_close(struct vsock_sock *vsk)
841{
842 struct sock *sk = &vsk->sk;
843
3b4477d2
SH		 844 if (!(sk->sk_state == TCP_ESTABLISHED ||
845 sk->sk_state == TCP_CLOSING))
06a8fc78
AH		 846 return true;
847
848 /* Already received SHUTDOWN from peer, reply with RST */
849 if ((vsk->peer_shutdown & SHUTDOWN_MASK) == SHUTDOWN_MASK) {
850 (void)virtio_transport_reset(vsk, NULL);
851 return true;
852 }
853
854 if ((sk->sk_shutdown & SHUTDOWN_MASK) != SHUTDOWN_MASK)
855 (void)virtio_transport_shutdown(vsk, SHUTDOWN_MASK);
856
857 if (sock_flag(sk, SOCK_LINGER) && !(current->flags & PF_EXITING))
858 virtio_transport_wait_close(sk, sk->sk_lingertime);
859
860 if (sock_flag(sk, SOCK_DONE)) {
861 return true;
862 }
863
864 sock_hold(sk);
865 INIT_DELAYED_WORK(&vsk->close_work,
866 virtio_transport_close_timeout);
867 vsk->close_work_scheduled = true;
868 schedule_delayed_work(&vsk->close_work, VSOCK_CLOSE_TIMEOUT);
869 return false;
870}
871
872void virtio_transport_release(struct vsock_sock *vsk)
873{
ac03046e
SG		 874 struct virtio_vsock_sock *vvs = vsk->trans;
875 struct virtio_vsock_pkt *pkt, *tmp;
06a8fc78
AH		 876 struct sock *sk = &vsk->sk;
877 bool remove_sock = true;
878
0d9138ff 879 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
06a8fc78
AH		 880 if (sk->sk_type == SOCK_STREAM)
881 remove_sock = virtio_transport_close(vsk);
ac03046e
SG		 882
883 list_for_each_entry_safe(pkt, tmp, &vvs->rx_queue, list) {
884 list_del(&pkt->list);
885 virtio_transport_free_pkt(pkt);
886 }
06a8fc78
AH		 887 release_sock(sk);
888
889 if (remove_sock)
890 vsock_remove_sock(vsk);
891}
892EXPORT_SYMBOL_GPL(virtio_transport_release);
893
894static int
895virtio_transport_recv_connecting(struct sock *sk,
896 struct virtio_vsock_pkt *pkt)
897{
898 struct vsock_sock *vsk = vsock_sk(sk);
899 int err;
900 int skerr;
901
902 switch (le16_to_cpu(pkt->hdr.op)) {
903 case VIRTIO_VSOCK_OP_RESPONSE:
3b4477d2 904 sk->sk_state = TCP_ESTABLISHED;
06a8fc78
AH		 905 sk->sk_socket->state = SS_CONNECTED;
906 vsock_insert_connected(vsk);
907 sk->sk_state_change(sk);
908 break;
909 case VIRTIO_VSOCK_OP_INVALID:
910 break;
911 case VIRTIO_VSOCK_OP_RST:
912 skerr = ECONNRESET;
913 err = 0;
914 goto destroy;
915 default:
916 skerr = EPROTO;
917 err = -EINVAL;
918 goto destroy;
919 }
920 return 0;
921
922destroy:
923 virtio_transport_reset(vsk, pkt);
3b4477d2 924 sk->sk_state = TCP_CLOSE;
06a8fc78
AH		 925 sk->sk_err = skerr;
926 sk->sk_error_report(sk);
927 return err;
928}
929
473c7391
SG		 930static void
931virtio_transport_recv_enqueue(struct vsock_sock *vsk,
932 struct virtio_vsock_pkt *pkt)
933{
934 struct virtio_vsock_sock *vvs = vsk->trans;
ae6fcfbf 935 bool can_enqueue, free_pkt = false;
473c7391
SG		 936
937 pkt->len = le32_to_cpu(pkt->hdr.len);
938 pkt->off = 0;
939
940 spin_lock_bh(&vvs->rx_lock);
941
ae6fcfbf
SG		 942 can_enqueue = virtio_transport_inc_rx_pkt(vvs, pkt);
943 if (!can_enqueue) {
944 free_pkt = true;
945 goto out;
946 }
473c7391
SG		 947
948 /* Try to copy small packets into the buffer of last packet queued,
949 * to avoid wasting memory queueing the entire buffer with a small
950 * payload.
951 */
952 if (pkt->len <= GOOD_COPY_LEN && !list_empty(&vvs->rx_queue)) {
953 struct virtio_vsock_pkt *last_pkt;
954
955 last_pkt = list_last_entry(&vvs->rx_queue,
956 struct virtio_vsock_pkt, list);
957
958 /* If there is space in the last packet queued, we copy the
959 * new packet in its buffer.
960 */
961 if (pkt->len <= last_pkt->buf_len - last_pkt->len) {
962 memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
963 pkt->len);
964 last_pkt->len += pkt->len;
965 free_pkt = true;
966 goto out;
967 }
968 }
969
970 list_add_tail(&pkt->list, &vvs->rx_queue);
971
972out:
973 spin_unlock_bh(&vvs->rx_lock);
974 if (free_pkt)
975 virtio_transport_free_pkt(pkt);
976}
977
06a8fc78
AH		 978static int
979virtio_transport_recv_connected(struct sock *sk,
980 struct virtio_vsock_pkt *pkt)
981{
982 struct vsock_sock *vsk = vsock_sk(sk);
06a8fc78
AH		 983 int err = 0;
984
985 switch (le16_to_cpu(pkt->hdr.op)) {
986 case VIRTIO_VSOCK_OP_RW:
473c7391 987 virtio_transport_recv_enqueue(vsk, pkt);
06a8fc78
AH		 988 sk->sk_data_ready(sk);
989 return err;
990 case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
991 sk->sk_write_space(sk);
992 break;
993 case VIRTIO_VSOCK_OP_SHUTDOWN:
994 if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_RCV)
995 vsk->peer_shutdown |= RCV_SHUTDOWN;
996 if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_SEND)
997 vsk->peer_shutdown |= SEND_SHUTDOWN;
998 if (vsk->peer_shutdown == SHUTDOWN_MASK &&
ad8a7220
SG		 999 vsock_stream_has_data(vsk) <= 0 &&
1000 !sock_flag(sk, SOCK_DONE)) {
1001 (void)virtio_transport_reset(vsk, NULL);
1002
1003 virtio_transport_do_close(vsk, true);
42f5cda5 1004 }
06a8fc78
AH		 1005 if (le32_to_cpu(pkt->hdr.flags))
1006 sk->sk_state_change(sk);
1007 break;
1008 case VIRTIO_VSOCK_OP_RST:
1009 virtio_transport_do_close(vsk, true);
1010 break;
1011 default:
1012 err = -EINVAL;
1013 break;
1014 }
1015
1016 virtio_transport_free_pkt(pkt);
1017 return err;
1018}
1019
1020static void
1021virtio_transport_recv_disconnecting(struct sock *sk,
1022 struct virtio_vsock_pkt *pkt)
1023{
1024 struct vsock_sock *vsk = vsock_sk(sk);
1025
1026 if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
1027 virtio_transport_do_close(vsk, true);
1028}
1029
1030static int
1031virtio_transport_send_response(struct vsock_sock *vsk,
1032 struct virtio_vsock_pkt *pkt)
1033{
1034 struct virtio_vsock_pkt_info info = {
1035 .op = VIRTIO_VSOCK_OP_RESPONSE,
1036 .type = VIRTIO_VSOCK_TYPE_STREAM,
f83f12d6 1037 .remote_cid = le64_to_cpu(pkt->hdr.src_cid),
06a8fc78
AH		 1038 .remote_port = le32_to_cpu(pkt->hdr.src_port),
1039 .reply = true,
36d277ba 1040 .vsk = vsk,
06a8fc78
AH		 1041 };
1042
1043 return virtio_transport_send_pkt_info(vsk, &info);
1044}
1045
1046/* Handle server socket */
1047static int
1048virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt)
1049{
1050 struct vsock_sock *vsk = vsock_sk(sk);
1051 struct vsock_sock *vchild;
1052 struct sock *child;
1053
1054 if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_REQUEST) {
1055 virtio_transport_reset(vsk, pkt);
1056 return -EINVAL;
1057 }
1058
1059 if (sk_acceptq_is_full(sk)) {
1060 virtio_transport_reset(vsk, pkt);
1061 return -ENOMEM;
1062 }
1063
1064 child = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
1065 sk->sk_type, 0);
1066 if (!child) {
1067 virtio_transport_reset(vsk, pkt);
1068 return -ENOMEM;
1069 }
1070
7976a11b 1071 sk_acceptq_added(sk);
06a8fc78
AH		 1072
1073 lock_sock_nested(child, SINGLE_DEPTH_NESTING);
1074
3b4477d2 1075 child->sk_state = TCP_ESTABLISHED;
06a8fc78
AH		 1076
1077 vchild = vsock_sk(child);
f83f12d6 1078 vsock_addr_init(&vchild->local_addr, le64_to_cpu(pkt->hdr.dst_cid),
06a8fc78 1079 le32_to_cpu(pkt->hdr.dst_port));
f83f12d6 1080 vsock_addr_init(&vchild->remote_addr, le64_to_cpu(pkt->hdr.src_cid),
06a8fc78
AH		 1081 le32_to_cpu(pkt->hdr.src_port));
1082
1083 vsock_insert_connected(vchild);
1084 vsock_enqueue_accept(sk, child);
1085 virtio_transport_send_response(vchild, pkt);
1086
1087 release_sock(child);
1088
1089 sk->sk_data_ready(sk);
1090 return 0;
1091}
1092
1093static bool virtio_transport_space_update(struct sock *sk,
1094 struct virtio_vsock_pkt *pkt)
1095{
1096 struct vsock_sock *vsk = vsock_sk(sk);
1097 struct virtio_vsock_sock *vvs = vsk->trans;
1098 bool space_available;
1099
1100 /* buf_alloc and fwd_cnt is always included in the hdr */
1101 spin_lock_bh(&vvs->tx_lock);
1102 vvs->peer_buf_alloc = le32_to_cpu(pkt->hdr.buf_alloc);
1103 vvs->peer_fwd_cnt = le32_to_cpu(pkt->hdr.fwd_cnt);
1104 space_available = virtio_transport_has_space(vsk);
1105 spin_unlock_bh(&vvs->tx_lock);
1106 return space_available;
1107}
1108
1109/* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex
1110 * lock.
1111 */
1112void virtio_transport_recv_pkt(struct virtio_vsock_pkt *pkt)
1113{
1114 struct sockaddr_vm src, dst;
1115 struct vsock_sock *vsk;
1116 struct sock *sk;
1117 bool space_available;
1118
f83f12d6 1119 vsock_addr_init(&src, le64_to_cpu(pkt->hdr.src_cid),
06a8fc78 1120 le32_to_cpu(pkt->hdr.src_port));
f83f12d6 1121 vsock_addr_init(&dst, le64_to_cpu(pkt->hdr.dst_cid),
06a8fc78
AH		 1122 le32_to_cpu(pkt->hdr.dst_port));
1123
1124 trace_virtio_transport_recv_pkt(src.svm_cid, src.svm_port,
1125 dst.svm_cid, dst.svm_port,
1126 le32_to_cpu(pkt->hdr.len),
1127 le16_to_cpu(pkt->hdr.type),
1128 le16_to_cpu(pkt->hdr.op),
1129 le32_to_cpu(pkt->hdr.flags),
1130 le32_to_cpu(pkt->hdr.buf_alloc),
1131 le32_to_cpu(pkt->hdr.fwd_cnt));
1132
1133 if (le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_STREAM) {
1134 (void)virtio_transport_reset_no_sock(pkt);
1135 goto free_pkt;
1136 }
1137
1138 /* The socket must be in connected or bound table
1139 * otherwise send reset back
1140 */
1141 sk = vsock_find_connected_socket(&src, &dst);
1142 if (!sk) {
1143 sk = vsock_find_bound_socket(&dst);
1144 if (!sk) {
1145 (void)virtio_transport_reset_no_sock(pkt);
1146 goto free_pkt;
1147 }
1148 }
1149
1150 vsk = vsock_sk(sk);
1151
1152 space_available = virtio_transport_space_update(sk, pkt);
1153
1154 lock_sock(sk);
1155
1156 /* Update CID in case it has changed after a transport reset event */
1157 vsk->local_addr.svm_cid = dst.svm_cid;
1158
1159 if (space_available)
1160 sk->sk_write_space(sk);
1161
1162 switch (sk->sk_state) {
3b4477d2 1163 case TCP_LISTEN:
06a8fc78
AH		 1164 virtio_transport_recv_listen(sk, pkt);
1165 virtio_transport_free_pkt(pkt);
1166 break;
3b4477d2 1167 case TCP_SYN_SENT:
06a8fc78
AH		 1168 virtio_transport_recv_connecting(sk, pkt);
1169 virtio_transport_free_pkt(pkt);
1170 break;
3b4477d2 1171 case TCP_ESTABLISHED:
06a8fc78
AH		 1172 virtio_transport_recv_connected(sk, pkt);
1173 break;
3b4477d2 1174 case TCP_CLOSING:
06a8fc78
AH		 1175 virtio_transport_recv_disconnecting(sk, pkt);
1176 virtio_transport_free_pkt(pkt);
1177 break;
1178 default:
1179 virtio_transport_free_pkt(pkt);
1180 break;
1181 }
1182 release_sock(sk);
1183
1184 /* Release refcnt obtained when we fetched this socket out of the
1185 * bound or connected list.
1186 */
1187 sock_put(sk);
1188 return;
1189
1190free_pkt:
1191 virtio_transport_free_pkt(pkt);
1192}
1193EXPORT_SYMBOL_GPL(virtio_transport_recv_pkt);
1194
1195void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt)
1196{
1197 kfree(pkt->buf);
1198 kfree(pkt);
1199}
1200EXPORT_SYMBOL_GPL(virtio_transport_free_pkt);
1201
1202MODULE_LICENSE("GPL v2");
1203MODULE_AUTHOR("Asias He");
1204MODULE_DESCRIPTION("common code for virtio vsock");
Linux 6.x block layer and io_uring tree(s)