1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_VIRTIO_VSOCK_H
3 #define _LINUX_VIRTIO_VSOCK_H
4
5 #include <uapi/linux/virtio_vsock.h>
6 #include <linux/socket.h>
7 #include <net/sock.h>
8 #include <net/af_vsock.h>
9
10 #define VIRTIO_VSOCK_SKB_HEADROOM (sizeof(struct virtio_vsock_hdr))
11
12 struct virtio_vsock_skb_cb {
13 bool reply;
14 bool tap_delivered;
15 u32 offset;
16 };
17
18 #define VIRTIO_VSOCK_SKB_CB(skb) ((struct virtio_vsock_skb_cb *)((skb)->cb))
19
virtio_vsock_hdr(struct sk_buff * skb)20 static inline struct virtio_vsock_hdr *virtio_vsock_hdr(struct sk_buff *skb)
21 {
22 return (struct virtio_vsock_hdr *)skb->head;
23 }
24
virtio_vsock_skb_reply(struct sk_buff * skb)25 static inline bool virtio_vsock_skb_reply(struct sk_buff *skb)
26 {
27 return VIRTIO_VSOCK_SKB_CB(skb)->reply;
28 }
29
virtio_vsock_skb_set_reply(struct sk_buff * skb)30 static inline void virtio_vsock_skb_set_reply(struct sk_buff *skb)
31 {
32 VIRTIO_VSOCK_SKB_CB(skb)->reply = true;
33 }
34
virtio_vsock_skb_tap_delivered(struct sk_buff * skb)35 static inline bool virtio_vsock_skb_tap_delivered(struct sk_buff *skb)
36 {
37 return VIRTIO_VSOCK_SKB_CB(skb)->tap_delivered;
38 }
39
virtio_vsock_skb_set_tap_delivered(struct sk_buff * skb)40 static inline void virtio_vsock_skb_set_tap_delivered(struct sk_buff *skb)
41 {
42 VIRTIO_VSOCK_SKB_CB(skb)->tap_delivered = true;
43 }
44
virtio_vsock_skb_clear_tap_delivered(struct sk_buff * skb)45 static inline void virtio_vsock_skb_clear_tap_delivered(struct sk_buff *skb)
46 {
47 VIRTIO_VSOCK_SKB_CB(skb)->tap_delivered = false;
48 }
49
virtio_vsock_skb_put(struct sk_buff * skb,u32 len)50 static inline void virtio_vsock_skb_put(struct sk_buff *skb, u32 len)
51 {
52 DEBUG_NET_WARN_ON_ONCE(skb->len);
53
54 if (skb_is_nonlinear(skb))
55 skb->len = len;
56 else
57 skb_put(skb, len);
58 }
59
60 static inline struct sk_buff *
__virtio_vsock_alloc_skb_with_frags(unsigned int header_len,unsigned int data_len,gfp_t mask)61 __virtio_vsock_alloc_skb_with_frags(unsigned int header_len,
62 unsigned int data_len,
63 gfp_t mask)
64 {
65 struct sk_buff *skb;
66 int err;
67
68 skb = alloc_skb_with_frags(header_len, data_len,
69 PAGE_ALLOC_COSTLY_ORDER, &err, mask);
70 if (!skb)
71 return NULL;
72
73 skb_reserve(skb, VIRTIO_VSOCK_SKB_HEADROOM);
74 skb->data_len = data_len;
75 return skb;
76 }
77
78 static inline struct sk_buff *
virtio_vsock_alloc_linear_skb(unsigned int size,gfp_t mask)79 virtio_vsock_alloc_linear_skb(unsigned int size, gfp_t mask)
80 {
81 return __virtio_vsock_alloc_skb_with_frags(size, 0, mask);
82 }
83
virtio_vsock_alloc_skb(unsigned int size,gfp_t mask)84 static inline struct sk_buff *virtio_vsock_alloc_skb(unsigned int size, gfp_t mask)
85 {
86 if (size <= SKB_WITH_OVERHEAD(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER))
87 return virtio_vsock_alloc_linear_skb(size, mask);
88
89 size -= VIRTIO_VSOCK_SKB_HEADROOM;
90 return __virtio_vsock_alloc_skb_with_frags(VIRTIO_VSOCK_SKB_HEADROOM,
91 size, mask);
92 }
93
94 static inline void
virtio_vsock_skb_queue_head(struct sk_buff_head * list,struct sk_buff * skb)95 virtio_vsock_skb_queue_head(struct sk_buff_head *list, struct sk_buff *skb)
96 {
97 spin_lock_bh(&list->lock);
98 __skb_queue_head(list, skb);
99 spin_unlock_bh(&list->lock);
100 }
101
102 static inline void
virtio_vsock_skb_queue_tail(struct sk_buff_head * list,struct sk_buff * skb)103 virtio_vsock_skb_queue_tail(struct sk_buff_head *list, struct sk_buff *skb)
104 {
105 spin_lock_bh(&list->lock);
106 __skb_queue_tail(list, skb);
107 spin_unlock_bh(&list->lock);
108 }
109
virtio_vsock_skb_dequeue(struct sk_buff_head * list)110 static inline struct sk_buff *virtio_vsock_skb_dequeue(struct sk_buff_head *list)
111 {
112 struct sk_buff *skb;
113
114 spin_lock_bh(&list->lock);
115 skb = __skb_dequeue(list);
116 spin_unlock_bh(&list->lock);
117
118 return skb;
119 }
120
virtio_vsock_skb_queue_purge(struct sk_buff_head * list)121 static inline void virtio_vsock_skb_queue_purge(struct sk_buff_head *list)
122 {
123 spin_lock_bh(&list->lock);
124 __skb_queue_purge(list);
125 spin_unlock_bh(&list->lock);
126 }
127
virtio_vsock_skb_len(struct sk_buff * skb)128 static inline size_t virtio_vsock_skb_len(struct sk_buff *skb)
129 {
130 return (size_t)(skb_end_pointer(skb) - skb->head);
131 }
132
133 /* Dimension the RX SKB so that the entire thing fits exactly into
134 * a single 4KiB page. This avoids wasting memory due to alloc_skb()
135 * rounding up to the next page order and also means that we
136 * don't leave higher-order pages sitting around in the RX queue.
137 */
138 #define VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE SKB_WITH_OVERHEAD(1024 * 4)
139 #define VIRTIO_VSOCK_MAX_BUF_SIZE 0xFFFFFFFFUL
140 #define VIRTIO_VSOCK_MAX_PKT_BUF_SIZE (1024 * 64)
141
142 enum {
143 VSOCK_VQ_RX = 0, /* for host to guest data */
144 VSOCK_VQ_TX = 1, /* for guest to host data */
145 VSOCK_VQ_EVENT = 2,
146 VSOCK_VQ_MAX = 3,
147 };
148
149 /* Per-socket state (accessed via vsk->trans) */
150 struct virtio_vsock_sock {
151 struct vsock_sock *vsk;
152
153 spinlock_t tx_lock;
154 spinlock_t rx_lock;
155
156 /* Protected by tx_lock */
157 u32 tx_cnt;
158 u32 peer_fwd_cnt;
159 u32 peer_buf_alloc;
160 size_t bytes_unsent;
161
162 /* Protected by rx_lock */
163 u32 fwd_cnt;
164 u32 last_fwd_cnt;
165 u32 rx_bytes;
166 u32 buf_alloc;
167 u32 buf_used;
168 struct sk_buff_head rx_queue;
169 u32 msg_count;
170 };
171
172 struct virtio_vsock_pkt_info {
173 u32 remote_cid, remote_port;
174 struct vsock_sock *vsk;
175 struct msghdr *msg;
176 u32 pkt_len;
177 u16 type;
178 u16 op;
179 u32 flags;
180 bool reply;
181 };
182
183 struct virtio_transport {
184 /* This must be the first field */
185 struct vsock_transport transport;
186
187 /* Takes ownership of the packet */
188 int (*send_pkt)(struct sk_buff *skb);
189
190 /* Used in MSG_ZEROCOPY mode. Checks, that provided data
191 * (number of buffers) could be transmitted with zerocopy
192 * mode. If this callback is not implemented for the current
193 * transport - this means that this transport doesn't need
194 * extra checks and can perform zerocopy transmission by
195 * default.
196 */
197 bool (*can_msgzerocopy)(int bufs_num);
198 };
199
200 ssize_t
201 virtio_transport_stream_dequeue(struct vsock_sock *vsk,
202 struct msghdr *msg,
203 size_t len,
204 int type);
205 int
206 virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
207 struct msghdr *msg,
208 size_t len, int flags);
209
210 int
211 virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk,
212 struct msghdr *msg,
213 size_t len);
214 ssize_t
215 virtio_transport_seqpacket_dequeue(struct vsock_sock *vsk,
216 struct msghdr *msg,
217 int flags);
218 s64 virtio_transport_stream_has_data(struct vsock_sock *vsk);
219 s64 virtio_transport_stream_has_space(struct vsock_sock *vsk);
220 u32 virtio_transport_seqpacket_has_data(struct vsock_sock *vsk);
221
222 ssize_t virtio_transport_unsent_bytes(struct vsock_sock *vsk);
223
224 void virtio_transport_consume_skb_sent(struct sk_buff *skb,
225 bool consume);
226
227 int virtio_transport_do_socket_init(struct vsock_sock *vsk,
228 struct vsock_sock *psk);
229 int
230 virtio_transport_notify_poll_in(struct vsock_sock *vsk,
231 size_t target,
232 bool *data_ready_now);
233 int
234 virtio_transport_notify_poll_out(struct vsock_sock *vsk,
235 size_t target,
236 bool *space_available_now);
237
238 int virtio_transport_notify_recv_init(struct vsock_sock *vsk,
239 size_t target, struct vsock_transport_recv_notify_data *data);
240 int virtio_transport_notify_recv_pre_block(struct vsock_sock *vsk,
241 size_t target, struct vsock_transport_recv_notify_data *data);
242 int virtio_transport_notify_recv_pre_dequeue(struct vsock_sock *vsk,
243 size_t target, struct vsock_transport_recv_notify_data *data);
244 int virtio_transport_notify_recv_post_dequeue(struct vsock_sock *vsk,
245 size_t target, ssize_t copied, bool data_read,
246 struct vsock_transport_recv_notify_data *data);
247 int virtio_transport_notify_send_init(struct vsock_sock *vsk,
248 struct vsock_transport_send_notify_data *data);
249 int virtio_transport_notify_send_pre_block(struct vsock_sock *vsk,
250 struct vsock_transport_send_notify_data *data);
251 int virtio_transport_notify_send_pre_enqueue(struct vsock_sock *vsk,
252 struct vsock_transport_send_notify_data *data);
253 int virtio_transport_notify_send_post_enqueue(struct vsock_sock *vsk,
254 ssize_t written, struct vsock_transport_send_notify_data *data);
255 void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val);
256
257 u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk);
258 bool virtio_transport_stream_is_active(struct vsock_sock *vsk);
259 bool virtio_transport_stream_allow(u32 cid, u32 port);
260 int virtio_transport_dgram_bind(struct vsock_sock *vsk,
261 struct sockaddr_vm *addr);
262 bool virtio_transport_dgram_allow(u32 cid, u32 port);
263
264 int virtio_transport_connect(struct vsock_sock *vsk);
265
266 int virtio_transport_shutdown(struct vsock_sock *vsk, int mode);
267
268 void virtio_transport_release(struct vsock_sock *vsk);
269
270 ssize_t
271 virtio_transport_stream_enqueue(struct vsock_sock *vsk,
272 struct msghdr *msg,
273 size_t len);
274 int
275 virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
276 struct sockaddr_vm *remote_addr,
277 struct msghdr *msg,
278 size_t len);
279
280 void virtio_transport_destruct(struct vsock_sock *vsk);
281
282 void virtio_transport_recv_pkt(struct virtio_transport *t,
283 struct sk_buff *skb);
284 void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct sk_buff *skb);
285 u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 wanted);
286 void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit);
287 void virtio_transport_deliver_tap_pkt(struct sk_buff *skb);
288 int virtio_transport_purge_skbs(void *vsk, struct sk_buff_head *list);
289 int virtio_transport_read_skb(struct vsock_sock *vsk, skb_read_actor_t read_actor);
290 int virtio_transport_notify_set_rcvlowat(struct vsock_sock *vsk, int val);
291 #endif /* _LINUX_VIRTIO_VSOCK_H */
292