Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 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> |
| 13 | #include <linux/mmu_context.h> |
| 14 | #include <linux/miscdevice.h> |
| 15 | #include <linux/module.h> |
| 16 | #include <linux/mutex.h> |
| 17 | #include <linux/workqueue.h> |
| 18 | #include <linux/rcupdate.h> |
| 19 | #include <linux/file.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 20 | #include <linux/slab.h> |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 21 | |
| 22 | #include <linux/net.h> |
| 23 | #include <linux/if_packet.h> |
| 24 | #include <linux/if_arp.h> |
| 25 | #include <linux/if_tun.h> |
Arnd Bergmann | 501c774 | 2010-02-18 05:46:50 +0000 | [diff] [blame] | 26 | #include <linux/if_macvlan.h> |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 27 | |
| 28 | #include <net/sock.h> |
| 29 | |
| 30 | #include "vhost.h" |
| 31 | |
| 32 | /* Max number of bytes transferred before requeueing the job. |
| 33 | * Using this limit prevents one virtqueue from starving others. */ |
| 34 | #define VHOST_NET_WEIGHT 0x80000 |
| 35 | |
| 36 | enum { |
| 37 | VHOST_NET_VQ_RX = 0, |
| 38 | VHOST_NET_VQ_TX = 1, |
| 39 | VHOST_NET_VQ_MAX = 2, |
| 40 | }; |
| 41 | |
| 42 | enum vhost_net_poll_state { |
| 43 | VHOST_NET_POLL_DISABLED = 0, |
| 44 | VHOST_NET_POLL_STARTED = 1, |
| 45 | VHOST_NET_POLL_STOPPED = 2, |
| 46 | }; |
| 47 | |
| 48 | struct vhost_net { |
| 49 | struct vhost_dev dev; |
| 50 | struct vhost_virtqueue vqs[VHOST_NET_VQ_MAX]; |
| 51 | struct vhost_poll poll[VHOST_NET_VQ_MAX]; |
| 52 | /* Tells us whether we are polling a socket for TX. |
| 53 | * We only do this when socket buffer fills up. |
| 54 | * Protected by tx vq lock. */ |
| 55 | enum vhost_net_poll_state tx_poll_state; |
| 56 | }; |
| 57 | |
| 58 | /* Pop first len bytes from iovec. Return number of segments used. */ |
| 59 | static int move_iovec_hdr(struct iovec *from, struct iovec *to, |
| 60 | size_t len, int iov_count) |
| 61 | { |
| 62 | int seg = 0; |
| 63 | size_t size; |
| 64 | while (len && seg < iov_count) { |
| 65 | size = min(from->iov_len, len); |
| 66 | to->iov_base = from->iov_base; |
| 67 | to->iov_len = size; |
| 68 | from->iov_len -= size; |
| 69 | from->iov_base += size; |
| 70 | len -= size; |
| 71 | ++from; |
| 72 | ++to; |
| 73 | ++seg; |
| 74 | } |
| 75 | return seg; |
| 76 | } |
| 77 | |
| 78 | /* Caller must have TX VQ lock */ |
| 79 | static void tx_poll_stop(struct vhost_net *net) |
| 80 | { |
| 81 | if (likely(net->tx_poll_state != VHOST_NET_POLL_STARTED)) |
| 82 | return; |
| 83 | vhost_poll_stop(net->poll + VHOST_NET_VQ_TX); |
| 84 | net->tx_poll_state = VHOST_NET_POLL_STOPPED; |
| 85 | } |
| 86 | |
| 87 | /* Caller must have TX VQ lock */ |
| 88 | static void tx_poll_start(struct vhost_net *net, struct socket *sock) |
| 89 | { |
| 90 | if (unlikely(net->tx_poll_state != VHOST_NET_POLL_STOPPED)) |
| 91 | return; |
| 92 | vhost_poll_start(net->poll + VHOST_NET_VQ_TX, sock->file); |
| 93 | net->tx_poll_state = VHOST_NET_POLL_STARTED; |
| 94 | } |
| 95 | |
| 96 | /* Expects to be always run from workqueue - which acts as |
| 97 | * read-size critical section for our kind of RCU. */ |
| 98 | static void handle_tx(struct vhost_net *net) |
| 99 | { |
| 100 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX]; |
| 101 | unsigned head, out, in, s; |
| 102 | struct msghdr msg = { |
| 103 | .msg_name = NULL, |
| 104 | .msg_namelen = 0, |
| 105 | .msg_control = NULL, |
| 106 | .msg_controllen = 0, |
| 107 | .msg_iov = vq->iov, |
| 108 | .msg_flags = MSG_DONTWAIT, |
| 109 | }; |
| 110 | size_t len, total_len = 0; |
| 111 | int err, wmem; |
| 112 | size_t hdr_size; |
| 113 | struct socket *sock = rcu_dereference(vq->private_data); |
| 114 | if (!sock) |
| 115 | return; |
| 116 | |
| 117 | wmem = atomic_read(&sock->sk->sk_wmem_alloc); |
Sridhar Samudrala | 39286fa | 2010-02-28 19:39:16 +0200 | [diff] [blame] | 118 | if (wmem >= sock->sk->sk_sndbuf) { |
| 119 | mutex_lock(&vq->mutex); |
| 120 | tx_poll_start(net, sock); |
| 121 | mutex_unlock(&vq->mutex); |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 122 | return; |
Sridhar Samudrala | 39286fa | 2010-02-28 19:39:16 +0200 | [diff] [blame] | 123 | } |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 124 | |
| 125 | use_mm(net->dev.mm); |
| 126 | mutex_lock(&vq->mutex); |
| 127 | vhost_disable_notify(vq); |
| 128 | |
Michael S. Tsirkin | 0e25557 | 2010-03-08 23:24:22 +0200 | [diff] [blame] | 129 | if (wmem < sock->sk->sk_sndbuf / 2) |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 130 | tx_poll_stop(net); |
| 131 | hdr_size = vq->hdr_size; |
| 132 | |
| 133 | for (;;) { |
| 134 | head = vhost_get_vq_desc(&net->dev, vq, vq->iov, |
| 135 | ARRAY_SIZE(vq->iov), |
| 136 | &out, &in, |
| 137 | NULL, NULL); |
| 138 | /* Nothing new? Wait for eventfd to tell us they refilled. */ |
| 139 | if (head == vq->num) { |
| 140 | wmem = atomic_read(&sock->sk->sk_wmem_alloc); |
| 141 | if (wmem >= sock->sk->sk_sndbuf * 3 / 4) { |
| 142 | tx_poll_start(net, sock); |
| 143 | set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); |
| 144 | break; |
| 145 | } |
| 146 | if (unlikely(vhost_enable_notify(vq))) { |
| 147 | vhost_disable_notify(vq); |
| 148 | continue; |
| 149 | } |
| 150 | break; |
| 151 | } |
| 152 | if (in) { |
| 153 | vq_err(vq, "Unexpected descriptor format for TX: " |
| 154 | "out %d, int %d\n", out, in); |
| 155 | break; |
| 156 | } |
| 157 | /* Skip header. TODO: support TSO. */ |
| 158 | s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, out); |
| 159 | msg.msg_iovlen = out; |
| 160 | len = iov_length(vq->iov, out); |
| 161 | /* Sanity check */ |
| 162 | if (!len) { |
| 163 | vq_err(vq, "Unexpected header len for TX: " |
| 164 | "%zd expected %zd\n", |
| 165 | iov_length(vq->hdr, s), hdr_size); |
| 166 | break; |
| 167 | } |
| 168 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ |
| 169 | err = sock->ops->sendmsg(NULL, sock, &msg, len); |
| 170 | if (unlikely(err < 0)) { |
| 171 | vhost_discard_vq_desc(vq); |
| 172 | tx_poll_start(net, sock); |
| 173 | break; |
| 174 | } |
| 175 | if (err != len) |
| 176 | pr_err("Truncated TX packet: " |
| 177 | " len %d != %zd\n", err, len); |
| 178 | vhost_add_used_and_signal(&net->dev, vq, head, 0); |
| 179 | total_len += len; |
| 180 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { |
| 181 | vhost_poll_queue(&vq->poll); |
| 182 | break; |
| 183 | } |
| 184 | } |
| 185 | |
| 186 | mutex_unlock(&vq->mutex); |
| 187 | unuse_mm(net->dev.mm); |
| 188 | } |
| 189 | |
| 190 | /* Expects to be always run from workqueue - which acts as |
| 191 | * read-size critical section for our kind of RCU. */ |
| 192 | static void handle_rx(struct vhost_net *net) |
| 193 | { |
| 194 | struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX]; |
| 195 | unsigned head, out, in, log, s; |
| 196 | struct vhost_log *vq_log; |
| 197 | struct msghdr msg = { |
| 198 | .msg_name = NULL, |
| 199 | .msg_namelen = 0, |
| 200 | .msg_control = NULL, /* FIXME: get and handle RX aux data. */ |
| 201 | .msg_controllen = 0, |
| 202 | .msg_iov = vq->iov, |
| 203 | .msg_flags = MSG_DONTWAIT, |
| 204 | }; |
| 205 | |
| 206 | struct virtio_net_hdr hdr = { |
| 207 | .flags = 0, |
| 208 | .gso_type = VIRTIO_NET_HDR_GSO_NONE |
| 209 | }; |
| 210 | |
| 211 | size_t len, total_len = 0; |
| 212 | int err; |
| 213 | size_t hdr_size; |
| 214 | struct socket *sock = rcu_dereference(vq->private_data); |
| 215 | if (!sock || skb_queue_empty(&sock->sk->sk_receive_queue)) |
| 216 | return; |
| 217 | |
| 218 | use_mm(net->dev.mm); |
| 219 | mutex_lock(&vq->mutex); |
| 220 | vhost_disable_notify(vq); |
| 221 | hdr_size = vq->hdr_size; |
| 222 | |
| 223 | vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? |
| 224 | vq->log : NULL; |
| 225 | |
| 226 | for (;;) { |
| 227 | head = vhost_get_vq_desc(&net->dev, vq, vq->iov, |
| 228 | ARRAY_SIZE(vq->iov), |
| 229 | &out, &in, |
| 230 | vq_log, &log); |
| 231 | /* OK, now we need to know about added descriptors. */ |
| 232 | if (head == vq->num) { |
| 233 | if (unlikely(vhost_enable_notify(vq))) { |
| 234 | /* They have slipped one in as we were |
| 235 | * doing that: check again. */ |
| 236 | vhost_disable_notify(vq); |
| 237 | continue; |
| 238 | } |
| 239 | /* Nothing new? Wait for eventfd to tell us |
| 240 | * they refilled. */ |
| 241 | break; |
| 242 | } |
| 243 | /* We don't need to be notified again. */ |
| 244 | if (out) { |
| 245 | vq_err(vq, "Unexpected descriptor format for RX: " |
| 246 | "out %d, int %d\n", |
| 247 | out, in); |
| 248 | break; |
| 249 | } |
| 250 | /* Skip header. TODO: support TSO/mergeable rx buffers. */ |
| 251 | s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, in); |
| 252 | msg.msg_iovlen = in; |
| 253 | len = iov_length(vq->iov, in); |
| 254 | /* Sanity check */ |
| 255 | if (!len) { |
| 256 | vq_err(vq, "Unexpected header len for RX: " |
| 257 | "%zd expected %zd\n", |
| 258 | iov_length(vq->hdr, s), hdr_size); |
| 259 | break; |
| 260 | } |
| 261 | err = sock->ops->recvmsg(NULL, sock, &msg, |
| 262 | len, MSG_DONTWAIT | MSG_TRUNC); |
| 263 | /* TODO: Check specific error and bomb out unless EAGAIN? */ |
| 264 | if (err < 0) { |
| 265 | vhost_discard_vq_desc(vq); |
| 266 | break; |
| 267 | } |
| 268 | /* TODO: Should check and handle checksum. */ |
| 269 | if (err > len) { |
| 270 | pr_err("Discarded truncated rx packet: " |
| 271 | " len %d > %zd\n", err, len); |
| 272 | vhost_discard_vq_desc(vq); |
| 273 | continue; |
| 274 | } |
| 275 | len = err; |
| 276 | err = memcpy_toiovec(vq->hdr, (unsigned char *)&hdr, hdr_size); |
| 277 | if (err) { |
| 278 | vq_err(vq, "Unable to write vnet_hdr at addr %p: %d\n", |
| 279 | vq->iov->iov_base, err); |
| 280 | break; |
| 281 | } |
| 282 | len += hdr_size; |
| 283 | vhost_add_used_and_signal(&net->dev, vq, head, len); |
| 284 | if (unlikely(vq_log)) |
| 285 | vhost_log_write(vq, vq_log, log, len); |
| 286 | total_len += len; |
| 287 | if (unlikely(total_len >= VHOST_NET_WEIGHT)) { |
| 288 | vhost_poll_queue(&vq->poll); |
| 289 | break; |
| 290 | } |
| 291 | } |
| 292 | |
| 293 | mutex_unlock(&vq->mutex); |
| 294 | unuse_mm(net->dev.mm); |
| 295 | } |
| 296 | |
| 297 | static void handle_tx_kick(struct work_struct *work) |
| 298 | { |
| 299 | struct vhost_virtqueue *vq; |
| 300 | struct vhost_net *net; |
| 301 | vq = container_of(work, struct vhost_virtqueue, poll.work); |
| 302 | net = container_of(vq->dev, struct vhost_net, dev); |
| 303 | handle_tx(net); |
| 304 | } |
| 305 | |
| 306 | static void handle_rx_kick(struct work_struct *work) |
| 307 | { |
| 308 | struct vhost_virtqueue *vq; |
| 309 | struct vhost_net *net; |
| 310 | vq = container_of(work, struct vhost_virtqueue, poll.work); |
| 311 | net = container_of(vq->dev, struct vhost_net, dev); |
| 312 | handle_rx(net); |
| 313 | } |
| 314 | |
| 315 | static void handle_tx_net(struct work_struct *work) |
| 316 | { |
| 317 | struct vhost_net *net; |
| 318 | net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_TX].work); |
| 319 | handle_tx(net); |
| 320 | } |
| 321 | |
| 322 | static void handle_rx_net(struct work_struct *work) |
| 323 | { |
| 324 | struct vhost_net *net; |
| 325 | net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_RX].work); |
| 326 | handle_rx(net); |
| 327 | } |
| 328 | |
| 329 | static int vhost_net_open(struct inode *inode, struct file *f) |
| 330 | { |
| 331 | struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); |
| 332 | int r; |
| 333 | if (!n) |
| 334 | return -ENOMEM; |
| 335 | n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick; |
| 336 | n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick; |
| 337 | r = vhost_dev_init(&n->dev, n->vqs, VHOST_NET_VQ_MAX); |
| 338 | if (r < 0) { |
| 339 | kfree(n); |
| 340 | return r; |
| 341 | } |
| 342 | |
| 343 | vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT); |
| 344 | vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN); |
| 345 | n->tx_poll_state = VHOST_NET_POLL_DISABLED; |
| 346 | |
| 347 | f->private_data = n; |
| 348 | |
| 349 | return 0; |
| 350 | } |
| 351 | |
| 352 | static void vhost_net_disable_vq(struct vhost_net *n, |
| 353 | struct vhost_virtqueue *vq) |
| 354 | { |
| 355 | if (!vq->private_data) |
| 356 | return; |
| 357 | if (vq == n->vqs + VHOST_NET_VQ_TX) { |
| 358 | tx_poll_stop(n); |
| 359 | n->tx_poll_state = VHOST_NET_POLL_DISABLED; |
| 360 | } else |
| 361 | vhost_poll_stop(n->poll + VHOST_NET_VQ_RX); |
| 362 | } |
| 363 | |
| 364 | static void vhost_net_enable_vq(struct vhost_net *n, |
| 365 | struct vhost_virtqueue *vq) |
| 366 | { |
| 367 | struct socket *sock = vq->private_data; |
| 368 | if (!sock) |
| 369 | return; |
| 370 | if (vq == n->vqs + VHOST_NET_VQ_TX) { |
| 371 | n->tx_poll_state = VHOST_NET_POLL_STOPPED; |
| 372 | tx_poll_start(n, sock); |
| 373 | } else |
| 374 | vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file); |
| 375 | } |
| 376 | |
| 377 | static struct socket *vhost_net_stop_vq(struct vhost_net *n, |
| 378 | struct vhost_virtqueue *vq) |
| 379 | { |
| 380 | struct socket *sock; |
| 381 | |
| 382 | mutex_lock(&vq->mutex); |
| 383 | sock = vq->private_data; |
| 384 | vhost_net_disable_vq(n, vq); |
| 385 | rcu_assign_pointer(vq->private_data, NULL); |
| 386 | mutex_unlock(&vq->mutex); |
| 387 | return sock; |
| 388 | } |
| 389 | |
| 390 | static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, |
| 391 | struct socket **rx_sock) |
| 392 | { |
| 393 | *tx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_TX); |
| 394 | *rx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_RX); |
| 395 | } |
| 396 | |
| 397 | static void vhost_net_flush_vq(struct vhost_net *n, int index) |
| 398 | { |
| 399 | vhost_poll_flush(n->poll + index); |
| 400 | vhost_poll_flush(&n->dev.vqs[index].poll); |
| 401 | } |
| 402 | |
| 403 | static void vhost_net_flush(struct vhost_net *n) |
| 404 | { |
| 405 | vhost_net_flush_vq(n, VHOST_NET_VQ_TX); |
| 406 | vhost_net_flush_vq(n, VHOST_NET_VQ_RX); |
| 407 | } |
| 408 | |
| 409 | static int vhost_net_release(struct inode *inode, struct file *f) |
| 410 | { |
| 411 | struct vhost_net *n = f->private_data; |
| 412 | struct socket *tx_sock; |
| 413 | struct socket *rx_sock; |
| 414 | |
| 415 | vhost_net_stop(n, &tx_sock, &rx_sock); |
| 416 | vhost_net_flush(n); |
| 417 | vhost_dev_cleanup(&n->dev); |
| 418 | if (tx_sock) |
| 419 | fput(tx_sock->file); |
| 420 | if (rx_sock) |
| 421 | fput(rx_sock->file); |
| 422 | /* We do an extra flush before freeing memory, |
| 423 | * since jobs can re-queue themselves. */ |
| 424 | vhost_net_flush(n); |
| 425 | kfree(n); |
| 426 | return 0; |
| 427 | } |
| 428 | |
| 429 | static struct socket *get_raw_socket(int fd) |
| 430 | { |
| 431 | struct { |
| 432 | struct sockaddr_ll sa; |
| 433 | char buf[MAX_ADDR_LEN]; |
| 434 | } uaddr; |
| 435 | int uaddr_len = sizeof uaddr, r; |
| 436 | struct socket *sock = sockfd_lookup(fd, &r); |
| 437 | if (!sock) |
| 438 | return ERR_PTR(-ENOTSOCK); |
| 439 | |
| 440 | /* Parameter checking */ |
| 441 | if (sock->sk->sk_type != SOCK_RAW) { |
| 442 | r = -ESOCKTNOSUPPORT; |
| 443 | goto err; |
| 444 | } |
| 445 | |
| 446 | r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, |
| 447 | &uaddr_len, 0); |
| 448 | if (r) |
| 449 | goto err; |
| 450 | |
| 451 | if (uaddr.sa.sll_family != AF_PACKET) { |
| 452 | r = -EPFNOSUPPORT; |
| 453 | goto err; |
| 454 | } |
| 455 | return sock; |
| 456 | err: |
| 457 | fput(sock->file); |
| 458 | return ERR_PTR(r); |
| 459 | } |
| 460 | |
Arnd Bergmann | 501c774 | 2010-02-18 05:46:50 +0000 | [diff] [blame] | 461 | static struct socket *get_tap_socket(int fd) |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 462 | { |
| 463 | struct file *file = fget(fd); |
| 464 | struct socket *sock; |
| 465 | if (!file) |
| 466 | return ERR_PTR(-EBADF); |
| 467 | sock = tun_get_socket(file); |
Arnd Bergmann | 501c774 | 2010-02-18 05:46:50 +0000 | [diff] [blame] | 468 | if (!IS_ERR(sock)) |
| 469 | return sock; |
| 470 | sock = macvtap_get_socket(file); |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 471 | if (IS_ERR(sock)) |
| 472 | fput(file); |
| 473 | return sock; |
| 474 | } |
| 475 | |
| 476 | static struct socket *get_socket(int fd) |
| 477 | { |
| 478 | struct socket *sock; |
| 479 | /* special case to disable backend */ |
| 480 | if (fd == -1) |
| 481 | return NULL; |
| 482 | sock = get_raw_socket(fd); |
| 483 | if (!IS_ERR(sock)) |
| 484 | return sock; |
Arnd Bergmann | 501c774 | 2010-02-18 05:46:50 +0000 | [diff] [blame] | 485 | sock = get_tap_socket(fd); |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 486 | if (!IS_ERR(sock)) |
| 487 | return sock; |
| 488 | return ERR_PTR(-ENOTSOCK); |
| 489 | } |
| 490 | |
| 491 | static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) |
| 492 | { |
| 493 | struct socket *sock, *oldsock; |
| 494 | struct vhost_virtqueue *vq; |
| 495 | int r; |
| 496 | |
| 497 | mutex_lock(&n->dev.mutex); |
| 498 | r = vhost_dev_check_owner(&n->dev); |
| 499 | if (r) |
| 500 | goto err; |
| 501 | |
| 502 | if (index >= VHOST_NET_VQ_MAX) { |
| 503 | r = -ENOBUFS; |
| 504 | goto err; |
| 505 | } |
| 506 | vq = n->vqs + index; |
| 507 | mutex_lock(&vq->mutex); |
| 508 | |
| 509 | /* Verify that ring has been setup correctly. */ |
| 510 | if (!vhost_vq_access_ok(vq)) { |
| 511 | r = -EFAULT; |
Jeff Dike | 1dace8c | 2010-03-04 16:10:14 -0500 | [diff] [blame] | 512 | goto err_vq; |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 513 | } |
| 514 | sock = get_socket(fd); |
| 515 | if (IS_ERR(sock)) { |
| 516 | r = PTR_ERR(sock); |
Jeff Dike | 1dace8c | 2010-03-04 16:10:14 -0500 | [diff] [blame] | 517 | goto err_vq; |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 518 | } |
| 519 | |
| 520 | /* start polling new socket */ |
| 521 | oldsock = vq->private_data; |
| 522 | if (sock == oldsock) |
| 523 | goto done; |
| 524 | |
| 525 | vhost_net_disable_vq(n, vq); |
| 526 | rcu_assign_pointer(vq->private_data, sock); |
| 527 | vhost_net_enable_vq(n, vq); |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 528 | done: |
| 529 | if (oldsock) { |
| 530 | vhost_net_flush_vq(n, index); |
| 531 | fput(oldsock->file); |
| 532 | } |
Jeff Dike | 1dace8c | 2010-03-04 16:10:14 -0500 | [diff] [blame] | 533 | |
| 534 | err_vq: |
| 535 | mutex_unlock(&vq->mutex); |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 536 | err: |
| 537 | mutex_unlock(&n->dev.mutex); |
| 538 | return r; |
| 539 | } |
| 540 | |
| 541 | static long vhost_net_reset_owner(struct vhost_net *n) |
| 542 | { |
| 543 | struct socket *tx_sock = NULL; |
| 544 | struct socket *rx_sock = NULL; |
| 545 | long err; |
| 546 | mutex_lock(&n->dev.mutex); |
| 547 | err = vhost_dev_check_owner(&n->dev); |
| 548 | if (err) |
| 549 | goto done; |
| 550 | vhost_net_stop(n, &tx_sock, &rx_sock); |
| 551 | vhost_net_flush(n); |
| 552 | err = vhost_dev_reset_owner(&n->dev); |
| 553 | done: |
| 554 | mutex_unlock(&n->dev.mutex); |
| 555 | if (tx_sock) |
| 556 | fput(tx_sock->file); |
| 557 | if (rx_sock) |
| 558 | fput(rx_sock->file); |
| 559 | return err; |
| 560 | } |
| 561 | |
| 562 | static int vhost_net_set_features(struct vhost_net *n, u64 features) |
| 563 | { |
| 564 | size_t hdr_size = features & (1 << VHOST_NET_F_VIRTIO_NET_HDR) ? |
| 565 | sizeof(struct virtio_net_hdr) : 0; |
| 566 | int i; |
| 567 | mutex_lock(&n->dev.mutex); |
| 568 | if ((features & (1 << VHOST_F_LOG_ALL)) && |
| 569 | !vhost_log_access_ok(&n->dev)) { |
| 570 | mutex_unlock(&n->dev.mutex); |
| 571 | return -EFAULT; |
| 572 | } |
| 573 | n->dev.acked_features = features; |
| 574 | smp_wmb(); |
| 575 | for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { |
| 576 | mutex_lock(&n->vqs[i].mutex); |
| 577 | n->vqs[i].hdr_size = hdr_size; |
| 578 | mutex_unlock(&n->vqs[i].mutex); |
| 579 | } |
| 580 | vhost_net_flush(n); |
| 581 | mutex_unlock(&n->dev.mutex); |
| 582 | return 0; |
| 583 | } |
| 584 | |
| 585 | static long vhost_net_ioctl(struct file *f, unsigned int ioctl, |
| 586 | unsigned long arg) |
| 587 | { |
| 588 | struct vhost_net *n = f->private_data; |
| 589 | void __user *argp = (void __user *)arg; |
| 590 | u64 __user *featurep = argp; |
| 591 | struct vhost_vring_file backend; |
| 592 | u64 features; |
| 593 | int r; |
| 594 | switch (ioctl) { |
| 595 | case VHOST_NET_SET_BACKEND: |
Takuya Yoshikawa | d3553a5 | 2010-05-27 19:01:58 +0900 | [diff] [blame] | 596 | if (copy_from_user(&backend, argp, sizeof backend)) |
| 597 | return -EFAULT; |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 598 | return vhost_net_set_backend(n, backend.index, backend.fd); |
| 599 | case VHOST_GET_FEATURES: |
| 600 | features = VHOST_FEATURES; |
Takuya Yoshikawa | d3553a5 | 2010-05-27 19:01:58 +0900 | [diff] [blame] | 601 | if (copy_to_user(featurep, &features, sizeof features)) |
| 602 | return -EFAULT; |
| 603 | return 0; |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 604 | case VHOST_SET_FEATURES: |
Takuya Yoshikawa | d3553a5 | 2010-05-27 19:01:58 +0900 | [diff] [blame] | 605 | if (copy_from_user(&features, featurep, sizeof features)) |
| 606 | return -EFAULT; |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 607 | if (features & ~VHOST_FEATURES) |
| 608 | return -EOPNOTSUPP; |
| 609 | return vhost_net_set_features(n, features); |
| 610 | case VHOST_RESET_OWNER: |
| 611 | return vhost_net_reset_owner(n); |
| 612 | default: |
| 613 | mutex_lock(&n->dev.mutex); |
| 614 | r = vhost_dev_ioctl(&n->dev, ioctl, arg); |
| 615 | vhost_net_flush(n); |
| 616 | mutex_unlock(&n->dev.mutex); |
| 617 | return r; |
| 618 | } |
| 619 | } |
| 620 | |
| 621 | #ifdef CONFIG_COMPAT |
| 622 | static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, |
| 623 | unsigned long arg) |
| 624 | { |
| 625 | return vhost_net_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); |
| 626 | } |
| 627 | #endif |
| 628 | |
| 629 | const static struct file_operations vhost_net_fops = { |
| 630 | .owner = THIS_MODULE, |
| 631 | .release = vhost_net_release, |
| 632 | .unlocked_ioctl = vhost_net_ioctl, |
| 633 | #ifdef CONFIG_COMPAT |
| 634 | .compat_ioctl = vhost_net_compat_ioctl, |
| 635 | #endif |
| 636 | .open = vhost_net_open, |
| 637 | }; |
| 638 | |
| 639 | static struct miscdevice vhost_net_misc = { |
| 640 | VHOST_NET_MINOR, |
| 641 | "vhost-net", |
| 642 | &vhost_net_fops, |
| 643 | }; |
| 644 | |
Christoph Hellwig | a8d3782 | 2010-04-13 14:11:25 -0400 | [diff] [blame] | 645 | static int vhost_net_init(void) |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 646 | { |
| 647 | int r = vhost_init(); |
| 648 | if (r) |
| 649 | goto err_init; |
| 650 | r = misc_register(&vhost_net_misc); |
| 651 | if (r) |
| 652 | goto err_reg; |
| 653 | return 0; |
| 654 | err_reg: |
| 655 | vhost_cleanup(); |
| 656 | err_init: |
| 657 | return r; |
| 658 | |
| 659 | } |
| 660 | module_init(vhost_net_init); |
| 661 | |
Christoph Hellwig | a8d3782 | 2010-04-13 14:11:25 -0400 | [diff] [blame] | 662 | static void vhost_net_exit(void) |
Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 663 | { |
| 664 | misc_deregister(&vhost_net_misc); |
| 665 | vhost_cleanup(); |
| 666 | } |
| 667 | module_exit(vhost_net_exit); |
| 668 | |
| 669 | MODULE_VERSION("0.0.1"); |
| 670 | MODULE_LICENSE("GPL v2"); |
| 671 | MODULE_AUTHOR("Michael S. Tsirkin"); |
| 672 | MODULE_DESCRIPTION("Host kernel accelerator for virtio net"); |