blob: 3381c4f91a8cc236df0df8be59bd586538480498 [file] [log] [blame]
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001#include <linux/etherdevice.h>
2#include <linux/if_macvlan.h>
Basil Gorf09e2242012-05-03 22:55:24 +00003#include <linux/if_vlan.h>
Arnd Bergmann20d29d72010-01-30 12:24:26 +00004#include <linux/interrupt.h>
5#include <linux/nsproxy.h>
6#include <linux/compat.h>
7#include <linux/if_tun.h>
8#include <linux/module.h>
9#include <linux/skbuff.h>
10#include <linux/cache.h>
11#include <linux/sched.h>
12#include <linux/types.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090013#include <linux/slab.h>
Arnd Bergmann20d29d72010-01-30 12:24:26 +000014#include <linux/wait.h>
15#include <linux/cdev.h>
Al Viro40401532012-02-13 03:58:52 +000016#include <linux/idr.h>
Arnd Bergmann20d29d72010-01-30 12:24:26 +000017#include <linux/fs.h>
18
19#include <net/net_namespace.h>
20#include <net/rtnetlink.h>
21#include <net/sock.h>
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +000022#include <linux/virtio_net.h>
Arnd Bergmann20d29d72010-01-30 12:24:26 +000023
24/*
25 * A macvtap queue is the central object of this driver, it connects
26 * an open character device to a macvlan interface. There can be
27 * multiple queues on one interface, which map back to queues
28 * implemented in hardware on the underlying device.
29 *
30 * macvtap_proto is used to allocate queues through the sock allocation
31 * mechanism.
32 *
Arnd Bergmann20d29d72010-01-30 12:24:26 +000033 */
34struct macvtap_queue {
35 struct sock sk;
36 struct socket sock;
Eric Dumazet43815482010-04-29 11:01:49 +000037 struct socket_wq wq;
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +030038 int vnet_hdr_sz;
Eric Dumazet13707f92011-01-26 19:28:23 +000039 struct macvlan_dev __rcu *vlan;
Arnd Bergmann20d29d72010-01-30 12:24:26 +000040 struct file *file;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +000041 unsigned int flags;
Jason Wang376b1aa2013-06-05 23:54:38 +000042 u16 queue_index;
Jason Wang815f2362013-06-05 23:54:39 +000043 bool enabled;
44 struct list_head next;
Arnd Bergmann20d29d72010-01-30 12:24:26 +000045};
46
47static struct proto macvtap_proto = {
48 .name = "macvtap",
49 .owner = THIS_MODULE,
50 .obj_size = sizeof (struct macvtap_queue),
51};
52
53/*
Eric W. Biedermane09eff72011-10-20 04:29:24 +000054 * Variables for dealing with macvtaps device numbers.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000055 */
David S. Miller1ebed712010-07-10 19:25:50 -070056static dev_t macvtap_major;
Eric W. Biedermane09eff72011-10-20 04:29:24 +000057#define MACVTAP_NUM_DEVS (1U << MINORBITS)
58static DEFINE_MUTEX(minor_lock);
59static DEFINE_IDR(minor_idr);
60
Shirley Ma97bc3632011-07-06 12:26:11 +000061#define GOODCOPY_LEN 128
Arnd Bergmann20d29d72010-01-30 12:24:26 +000062static struct class *macvtap_class;
63static struct cdev macvtap_cdev;
64
Arnd Bergmann501c7742010-02-18 05:46:50 +000065static const struct proto_ops macvtap_socket_ops;
66
Vlad Yasevich2be5c762013-06-25 16:04:21 -040067#define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
68 NETIF_F_TSO6 | NETIF_F_UFO)
69#define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO)
Vlad Yasevicha567dd62013-08-16 15:25:00 -040070#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG)
71
Vlad Yasevich6acf54f2013-12-11 13:27:10 -050072static struct macvlan_dev *macvtap_get_vlan_rcu(const struct net_device *dev)
73{
74 return rcu_dereference(dev->rx_handler_data);
75}
76
Arnd Bergmann20d29d72010-01-30 12:24:26 +000077/*
78 * RCU usage:
Arnd Bergmann02df55d2010-02-18 05:45:36 +000079 * The macvtap_queue and the macvlan_dev are loosely coupled, the
80 * pointers from one to the other can only be read while rcu_read_lock
Vlad Yasevich441ac0f2013-06-25 16:04:19 -040081 * or rtnl is held.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000082 *
Arnd Bergmann02df55d2010-02-18 05:45:36 +000083 * Both the file and the macvlan_dev hold a reference on the macvtap_queue
84 * through sock_hold(&q->sk). When the macvlan_dev goes away first,
85 * q->vlan becomes inaccessible. When the files gets closed,
86 * macvtap_get_queue() fails.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000087 *
Arnd Bergmann02df55d2010-02-18 05:45:36 +000088 * There may still be references to the struct sock inside of the
89 * queue from outbound SKBs, but these never reference back to the
90 * file or the dev. The data structure is freed through __sk_free
91 * when both our references and any pending SKBs are gone.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000092 */
Arnd Bergmann20d29d72010-01-30 12:24:26 +000093
Jason Wang815f2362013-06-05 23:54:39 +000094static int macvtap_enable_queue(struct net_device *dev, struct file *file,
Arnd Bergmann20d29d72010-01-30 12:24:26 +000095 struct macvtap_queue *q)
96{
97 struct macvlan_dev *vlan = netdev_priv(dev);
Jason Wang815f2362013-06-05 23:54:39 +000098 int err = -EINVAL;
99
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400100 ASSERT_RTNL();
Jason Wang815f2362013-06-05 23:54:39 +0000101
102 if (q->enabled)
103 goto out;
104
105 err = 0;
106 rcu_assign_pointer(vlan->taps[vlan->numvtaps], q);
107 q->queue_index = vlan->numvtaps;
108 q->enabled = true;
109
110 vlan->numvtaps++;
111out:
Jason Wang815f2362013-06-05 23:54:39 +0000112 return err;
113}
114
115static int macvtap_set_queue(struct net_device *dev, struct file *file,
116 struct macvtap_queue *q)
117{
118 struct macvlan_dev *vlan = netdev_priv(dev);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000119 int err = -EBUSY;
120
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400121 rtnl_lock();
Jason Wang815f2362013-06-05 23:54:39 +0000122 if (vlan->numqueues == MAX_MACVTAP_QUEUES)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000123 goto out;
124
125 err = 0;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000126 rcu_assign_pointer(q->vlan, vlan);
Jason Wang376b1aa2013-06-05 23:54:38 +0000127 rcu_assign_pointer(vlan->taps[vlan->numvtaps], q);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000128 sock_hold(&q->sk);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000129
130 q->file = file;
Jason Wang376b1aa2013-06-05 23:54:38 +0000131 q->queue_index = vlan->numvtaps;
Jason Wang815f2362013-06-05 23:54:39 +0000132 q->enabled = true;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000133 file->private_data = q;
Jason Wang815f2362013-06-05 23:54:39 +0000134 list_add_tail(&q->next, &vlan->queue_list);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000135
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000136 vlan->numvtaps++;
Jason Wang815f2362013-06-05 23:54:39 +0000137 vlan->numqueues++;
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000138
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000139out:
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400140 rtnl_unlock();
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000141 return err;
142}
143
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400144static int macvtap_disable_queue(struct macvtap_queue *q)
Jason Wang815f2362013-06-05 23:54:39 +0000145{
146 struct macvlan_dev *vlan;
147 struct macvtap_queue *nq;
148
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400149 ASSERT_RTNL();
Jason Wang815f2362013-06-05 23:54:39 +0000150 if (!q->enabled)
151 return -EINVAL;
152
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400153 vlan = rtnl_dereference(q->vlan);
154
Jason Wang815f2362013-06-05 23:54:39 +0000155 if (vlan) {
156 int index = q->queue_index;
157 BUG_ON(index >= vlan->numvtaps);
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400158 nq = rtnl_dereference(vlan->taps[vlan->numvtaps - 1]);
Jason Wang815f2362013-06-05 23:54:39 +0000159 nq->queue_index = index;
160
161 rcu_assign_pointer(vlan->taps[index], nq);
162 RCU_INIT_POINTER(vlan->taps[vlan->numvtaps - 1], NULL);
163 q->enabled = false;
164
165 vlan->numvtaps--;
166 }
167
168 return 0;
169}
170
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000171/*
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000172 * The file owning the queue got closed, give up both
173 * the reference that the files holds as well as the
174 * one from the macvlan_dev if that still exists.
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000175 *
176 * Using the spinlock makes sure that we don't get
177 * to the queue again after destroying it.
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000178 */
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000179static void macvtap_put_queue(struct macvtap_queue *q)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000180{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000181 struct macvlan_dev *vlan;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000182
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400183 rtnl_lock();
184 vlan = rtnl_dereference(q->vlan);
185
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000186 if (vlan) {
Jason Wang815f2362013-06-05 23:54:39 +0000187 if (q->enabled)
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400188 BUG_ON(macvtap_disable_queue(q));
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000189
Jason Wang815f2362013-06-05 23:54:39 +0000190 vlan->numqueues--;
Eric Dumazet2cfa5a02011-11-23 07:09:32 +0000191 RCU_INIT_POINTER(q->vlan, NULL);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000192 sock_put(&q->sk);
Jason Wang815f2362013-06-05 23:54:39 +0000193 list_del_init(&q->next);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000194 }
195
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400196 rtnl_unlock();
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000197
198 synchronize_rcu();
199 sock_put(&q->sk);
200}
201
202/*
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000203 * Select a queue based on the rxq of the device on which this packet
204 * arrived. If the incoming device is not mq, calculate a flow hash
205 * to select a queue. If all fails, find the first available queue.
206 * Cache vlan->numvtaps since it can become zero during the execution
207 * of this function.
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000208 */
209static struct macvtap_queue *macvtap_get_queue(struct net_device *dev,
210 struct sk_buff *skb)
211{
212 struct macvlan_dev *vlan = netdev_priv(dev);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000213 struct macvtap_queue *tap = NULL;
Jason Wang815f2362013-06-05 23:54:39 +0000214 /* Access to taps array is protected by rcu, but access to numvtaps
215 * isn't. Below we use it to lookup a queue, but treat it as a hint
216 * and validate that the result isn't NULL - in case we are
217 * racing against queue removal.
218 */
Jason Wanged0483f2013-06-05 23:54:33 +0000219 int numvtaps = ACCESS_ONCE(vlan->numvtaps);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000220 __u32 rxq;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000221
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000222 if (!numvtaps)
223 goto out;
224
Krishna Kumaref0002b2011-11-23 22:17:14 +0000225 /* Check if we can use flow to select a queue */
Tom Herbert3958afa1b2013-12-15 22:12:06 -0800226 rxq = skb_get_hash(skb);
Krishna Kumaref0002b2011-11-23 22:17:14 +0000227 if (rxq) {
228 tap = rcu_dereference(vlan->taps[rxq % numvtaps]);
Jason Wang376b1aa2013-06-05 23:54:38 +0000229 goto out;
Krishna Kumaref0002b2011-11-23 22:17:14 +0000230 }
231
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000232 if (likely(skb_rx_queue_recorded(skb))) {
233 rxq = skb_get_rx_queue(skb);
234
235 while (unlikely(rxq >= numvtaps))
236 rxq -= numvtaps;
237
238 tap = rcu_dereference(vlan->taps[rxq]);
Jason Wang376b1aa2013-06-05 23:54:38 +0000239 goto out;
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000240 }
241
Jason Wang376b1aa2013-06-05 23:54:38 +0000242 tap = rcu_dereference(vlan->taps[0]);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000243out:
244 return tap;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000245}
246
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000247/*
248 * The net_device is going away, give up the reference
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000249 * that it holds on all queues and safely set the pointer
250 * from the queues to NULL.
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000251 */
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000252static void macvtap_del_queues(struct net_device *dev)
253{
254 struct macvlan_dev *vlan = netdev_priv(dev);
Jason Wang815f2362013-06-05 23:54:39 +0000255 struct macvtap_queue *q, *tmp, *qlist[MAX_MACVTAP_QUEUES];
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000256 int i, j = 0;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000257
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400258 ASSERT_RTNL();
Jason Wang815f2362013-06-05 23:54:39 +0000259 list_for_each_entry_safe(q, tmp, &vlan->queue_list, next) {
260 list_del_init(&q->next);
Jason Wang376b1aa2013-06-05 23:54:38 +0000261 qlist[j++] = q;
Jason Wang376b1aa2013-06-05 23:54:38 +0000262 RCU_INIT_POINTER(q->vlan, NULL);
Jason Wang815f2362013-06-05 23:54:39 +0000263 if (q->enabled)
264 vlan->numvtaps--;
265 vlan->numqueues--;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000266 }
Jason Wang815f2362013-06-05 23:54:39 +0000267 for (i = 0; i < vlan->numvtaps; i++)
268 RCU_INIT_POINTER(vlan->taps[i], NULL);
269 BUG_ON(vlan->numvtaps);
270 BUG_ON(vlan->numqueues);
Eric W. Biederman99f34b32011-10-20 04:26:01 +0000271 /* guarantee that any future macvtap_set_queue will fail */
272 vlan->numvtaps = MAX_MACVTAP_QUEUES;
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000273
274 for (--j; j >= 0; j--)
275 sock_put(&qlist[j]->sk);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000276}
277
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500278static rx_handler_result_t macvtap_handle_frame(struct sk_buff **pskb)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000279{
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500280 struct sk_buff *skb = *pskb;
281 struct net_device *dev = skb->dev;
282 struct macvlan_dev *vlan;
283 struct macvtap_queue *q;
Vlad Yasevicha567dd62013-08-16 15:25:00 -0400284 netdev_features_t features = TAP_FEATURES;
285
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500286 vlan = macvtap_get_vlan_rcu(dev);
287 if (!vlan)
288 return RX_HANDLER_PASS;
289
290 q = macvtap_get_queue(dev, skb);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000291 if (!q)
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500292 return RX_HANDLER_PASS;
Herbert Xu8a357472010-07-21 21:44:31 +0000293
294 if (skb_queue_len(&q->sk.sk_receive_queue) >= dev->tx_queue_len)
295 goto drop;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000296
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500297 skb_push(skb, ETH_HLEN);
298
Vlad Yasevich3e4f8b72013-06-25 16:04:22 -0400299 /* Apply the forward feature mask so that we perform segmentation
Vlad Yaseviche5733322013-08-16 15:25:02 -0400300 * according to users wishes. This only works if VNET_HDR is
301 * enabled.
Vlad Yasevich3e4f8b72013-06-25 16:04:22 -0400302 */
Vlad Yaseviche5733322013-08-16 15:25:02 -0400303 if (q->flags & IFF_VNET_HDR)
304 features |= vlan->tap_features;
Vlad Yasevich3e4f8b72013-06-25 16:04:22 -0400305 if (netif_needs_gso(skb, features)) {
306 struct sk_buff *segs = __skb_gso_segment(skb, features, false);
307
308 if (IS_ERR(segs))
309 goto drop;
310
311 if (!segs) {
312 skb_queue_tail(&q->sk.sk_receive_queue, skb);
313 goto wake_up;
314 }
315
316 kfree_skb(skb);
317 while (segs) {
318 struct sk_buff *nskb = segs->next;
319
320 segs->next = NULL;
321 skb_queue_tail(&q->sk.sk_receive_queue, segs);
322 segs = nskb;
323 }
324 } else {
Vlad Yasevichcbdb0422014-04-29 10:09:50 -0400325 /* If we receive a partial checksum and the tap side
326 * doesn't support checksum offload, compute the checksum.
327 * Note: it doesn't matter which checksum feature to
328 * check, we either support them all or none.
329 */
330 if (skb->ip_summed == CHECKSUM_PARTIAL &&
331 !(features & NETIF_F_ALL_CSUM) &&
332 skb_checksum_help(skb))
333 goto drop;
Vlad Yasevich3e4f8b72013-06-25 16:04:22 -0400334 skb_queue_tail(&q->sk.sk_receive_queue, skb);
335 }
336
337wake_up:
Eric Dumazet4a4771a2010-04-25 22:20:06 +0000338 wake_up_interruptible_poll(sk_sleep(&q->sk), POLLIN | POLLRDNORM | POLLRDBAND);
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500339 return RX_HANDLER_CONSUMED;
Herbert Xu8a357472010-07-21 21:44:31 +0000340
341drop:
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500342 /* Count errors/drops only here, thus don't care about args. */
343 macvlan_count_rx(vlan, 0, 0, 0);
Herbert Xu8a357472010-07-21 21:44:31 +0000344 kfree_skb(skb);
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500345 return RX_HANDLER_CONSUMED;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000346}
347
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000348static int macvtap_get_minor(struct macvlan_dev *vlan)
349{
350 int retval = -ENOMEM;
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000351
352 mutex_lock(&minor_lock);
Tejun Heoec09ebc2013-02-27 17:04:34 -0800353 retval = idr_alloc(&minor_idr, vlan, 1, MACVTAP_NUM_DEVS, GFP_KERNEL);
354 if (retval >= 0) {
355 vlan->minor = retval;
356 } else if (retval == -ENOSPC) {
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000357 printk(KERN_ERR "too many macvtap devices\n");
358 retval = -EINVAL;
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000359 }
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000360 mutex_unlock(&minor_lock);
Tejun Heoec09ebc2013-02-27 17:04:34 -0800361 return retval < 0 ? retval : 0;
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000362}
363
364static void macvtap_free_minor(struct macvlan_dev *vlan)
365{
366 mutex_lock(&minor_lock);
367 if (vlan->minor) {
368 idr_remove(&minor_idr, vlan->minor);
369 vlan->minor = 0;
370 }
371 mutex_unlock(&minor_lock);
372}
373
374static struct net_device *dev_get_by_macvtap_minor(int minor)
375{
376 struct net_device *dev = NULL;
377 struct macvlan_dev *vlan;
378
379 mutex_lock(&minor_lock);
380 vlan = idr_find(&minor_idr, minor);
381 if (vlan) {
382 dev = vlan->dev;
383 dev_hold(dev);
384 }
385 mutex_unlock(&minor_lock);
386 return dev;
387}
388
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000389static int macvtap_newlink(struct net *src_net,
390 struct net_device *dev,
391 struct nlattr *tb[],
392 struct nlattr *data[])
393{
Jason Wang815f2362013-06-05 23:54:39 +0000394 struct macvlan_dev *vlan = netdev_priv(dev);
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500395 int err;
396
Jason Wang815f2362013-06-05 23:54:39 +0000397 INIT_LIST_HEAD(&vlan->queue_list);
398
Vlad Yasevich2be5c762013-06-25 16:04:21 -0400399 /* Since macvlan supports all offloads by default, make
400 * tap support all offloads also.
401 */
402 vlan->tap_features = TUN_OFFLOADS;
403
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500404 err = netdev_rx_handler_register(dev, macvtap_handle_frame, vlan);
405 if (err)
406 return err;
407
Eric W. Biederman9bf19072011-10-20 04:28:46 +0000408 /* Don't put anything that may fail after macvlan_common_newlink
409 * because we can't undo what it does.
410 */
Vlad Yasevich2f6a1b62013-12-11 13:27:11 -0500411 return macvlan_common_newlink(src_net, dev, tb, data);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000412}
413
414static void macvtap_dellink(struct net_device *dev,
415 struct list_head *head)
416{
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500417 netdev_rx_handler_unregister(dev);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000418 macvtap_del_queues(dev);
419 macvlan_dellink(dev, head);
420}
421
Herbert Xu8a357472010-07-21 21:44:31 +0000422static void macvtap_setup(struct net_device *dev)
423{
424 macvlan_common_setup(dev);
425 dev->tx_queue_len = TUN_READQ_SIZE;
426}
427
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000428static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
429 .kind = "macvtap",
Herbert Xu8a357472010-07-21 21:44:31 +0000430 .setup = macvtap_setup,
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000431 .newlink = macvtap_newlink,
432 .dellink = macvtap_dellink,
433};
434
435
436static void macvtap_sock_write_space(struct sock *sk)
437{
Eric Dumazet43815482010-04-29 11:01:49 +0000438 wait_queue_head_t *wqueue;
439
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000440 if (!sock_writeable(sk) ||
441 !test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
442 return;
443
Eric Dumazet43815482010-04-29 11:01:49 +0000444 wqueue = sk_sleep(sk);
445 if (wqueue && waitqueue_active(wqueue))
446 wake_up_interruptible_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000447}
448
Eric W. Biederman2259fef2011-10-20 04:27:24 +0000449static void macvtap_sock_destruct(struct sock *sk)
450{
451 skb_queue_purge(&sk->sk_receive_queue);
452}
453
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000454static int macvtap_open(struct inode *inode, struct file *file)
455{
456 struct net *net = current->nsproxy->net_ns;
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000457 struct net_device *dev = dev_get_by_macvtap_minor(iminor(inode));
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000458 struct macvtap_queue *q;
459 int err;
460
461 err = -ENODEV;
462 if (!dev)
463 goto out;
464
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000465 err = -ENOMEM;
466 q = (struct macvtap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL,
467 &macvtap_proto);
468 if (!q)
469 goto out;
470
Jason Wangd9a90a32013-06-13 14:23:35 +0800471 RCU_INIT_POINTER(q->sock.wq, &q->wq);
Eric Dumazet43815482010-04-29 11:01:49 +0000472 init_waitqueue_head(&q->wq.wait);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000473 q->sock.type = SOCK_RAW;
474 q->sock.state = SS_CONNECTED;
Arnd Bergmann501c7742010-02-18 05:46:50 +0000475 q->sock.file = file;
476 q->sock.ops = &macvtap_socket_ops;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000477 sock_init_data(&q->sock, &q->sk);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000478 q->sk.sk_write_space = macvtap_sock_write_space;
Eric W. Biederman2259fef2011-10-20 04:27:24 +0000479 q->sk.sk_destruct = macvtap_sock_destruct;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000480 q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP;
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300481 q->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000482
Shirley Ma97bc3632011-07-06 12:26:11 +0000483 /*
484 * so far only KVM virtio_net uses macvtap, enable zero copy between
485 * guest kernel and host kernel when lower device supports zerocopy
Eric W. Biederman047af9cf2011-10-20 04:26:39 +0000486 *
487 * The macvlan supports zerocopy iff the lower device supports zero
488 * copy so we don't have to look at the lower device directly.
Shirley Ma97bc3632011-07-06 12:26:11 +0000489 */
Eric W. Biederman047af9cf2011-10-20 04:26:39 +0000490 if ((dev->features & NETIF_F_HIGHDMA) && (dev->features & NETIF_F_SG))
491 sock_set_flag(&q->sk, SOCK_ZEROCOPY);
Shirley Ma97bc3632011-07-06 12:26:11 +0000492
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000493 err = macvtap_set_queue(dev, file, q);
494 if (err)
495 sock_put(&q->sk);
496
497out:
498 if (dev)
499 dev_put(dev);
500
501 return err;
502}
503
504static int macvtap_release(struct inode *inode, struct file *file)
505{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000506 struct macvtap_queue *q = file->private_data;
507 macvtap_put_queue(q);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000508 return 0;
509}
510
511static unsigned int macvtap_poll(struct file *file, poll_table * wait)
512{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000513 struct macvtap_queue *q = file->private_data;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000514 unsigned int mask = POLLERR;
515
516 if (!q)
517 goto out;
518
519 mask = 0;
Eric Dumazet43815482010-04-29 11:01:49 +0000520 poll_wait(file, &q->wq.wait, wait);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000521
522 if (!skb_queue_empty(&q->sk.sk_receive_queue))
523 mask |= POLLIN | POLLRDNORM;
524
525 if (sock_writeable(&q->sk) ||
526 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &q->sock.flags) &&
527 sock_writeable(&q->sk)))
528 mask |= POLLOUT | POLLWRNORM;
529
530out:
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000531 return mask;
532}
533
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000534static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad,
535 size_t len, size_t linear,
536 int noblock, int *err)
537{
538 struct sk_buff *skb;
539
540 /* Under a page? Don't bother with paged skb. */
541 if (prepad + len < PAGE_SIZE || !linear)
542 linear = len;
543
544 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
Eric Dumazet28d64272013-08-08 14:38:47 -0700545 err, 0);
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000546 if (!skb)
547 return NULL;
548
549 skb_reserve(skb, prepad);
550 skb_put(skb, linear);
551 skb->data_len = len - linear;
552 skb->len += len - linear;
553
554 return skb;
555}
556
557/*
558 * macvtap_skb_from_vnet_hdr and macvtap_skb_to_vnet_hdr should
559 * be shared with the tun/tap driver.
560 */
561static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
562 struct virtio_net_hdr *vnet_hdr)
563{
564 unsigned short gso_type = 0;
565 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
566 switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
567 case VIRTIO_NET_HDR_GSO_TCPV4:
568 gso_type = SKB_GSO_TCPV4;
569 break;
570 case VIRTIO_NET_HDR_GSO_TCPV6:
571 gso_type = SKB_GSO_TCPV6;
572 break;
573 case VIRTIO_NET_HDR_GSO_UDP:
574 gso_type = SKB_GSO_UDP;
575 break;
576 default:
577 return -EINVAL;
578 }
579
580 if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
581 gso_type |= SKB_GSO_TCP_ECN;
582
583 if (vnet_hdr->gso_size == 0)
584 return -EINVAL;
585 }
586
587 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
588 if (!skb_partial_csum_set(skb, vnet_hdr->csum_start,
589 vnet_hdr->csum_offset))
590 return -EINVAL;
591 }
592
593 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
594 skb_shinfo(skb)->gso_size = vnet_hdr->gso_size;
Pravin B Shelarc9af6db2013-02-11 09:27:41 +0000595 skb_shinfo(skb)->gso_type = gso_type;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000596
597 /* Header must be checked, and gso_segs computed. */
598 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
599 skb_shinfo(skb)->gso_segs = 0;
600 }
601 return 0;
602}
603
Zhi Yong Wu359d44d2013-12-07 04:13:04 +0800604static void macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000605 struct virtio_net_hdr *vnet_hdr)
606{
607 memset(vnet_hdr, 0, sizeof(*vnet_hdr));
608
609 if (skb_is_gso(skb)) {
610 struct skb_shared_info *sinfo = skb_shinfo(skb);
611
612 /* This is a hint as to how much should be linear. */
613 vnet_hdr->hdr_len = skb_headlen(skb);
614 vnet_hdr->gso_size = sinfo->gso_size;
615 if (sinfo->gso_type & SKB_GSO_TCPV4)
616 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
617 else if (sinfo->gso_type & SKB_GSO_TCPV6)
618 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
619 else if (sinfo->gso_type & SKB_GSO_UDP)
620 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
621 else
622 BUG();
623 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
624 vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
625 } else
626 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
627
628 if (skb->ip_summed == CHECKSUM_PARTIAL) {
629 vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
Michał Mirosław55508d62010-12-14 15:24:08 +0000630 vnet_hdr->csum_start = skb_checksum_start_offset(skb);
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000631 vnet_hdr->csum_offset = skb->csum_offset;
Jason Wang10a8d942011-06-10 00:56:17 +0000632 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
633 vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000634 } /* else everything is zero */
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000635}
636
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000637/* Get packet from user space buffer */
Shirley Ma97bc3632011-07-06 12:26:11 +0000638static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
639 const struct iovec *iv, unsigned long total_len,
640 size_t count, int noblock)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000641{
Jason Wang16a3fa22013-11-13 14:00:40 +0800642 int good_linear = SKB_MAX_HEAD(NET_IP_ALIGN);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000643 struct sk_buff *skb;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000644 struct macvlan_dev *vlan;
Shirley Ma97bc3632011-07-06 12:26:11 +0000645 unsigned long len = total_len;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000646 int err;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000647 struct virtio_net_hdr vnet_hdr = { 0 };
648 int vnet_hdr_len = 0;
Jason Wangb92946e2012-05-02 11:42:15 +0800649 int copylen = 0;
Shirley Ma97bc3632011-07-06 12:26:11 +0000650 bool zerocopy = false;
Jason Wang61d46bf2013-07-10 13:43:28 +0800651 size_t linear;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000652
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000653 if (q->flags & IFF_VNET_HDR) {
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300654 vnet_hdr_len = q->vnet_hdr_sz;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000655
656 err = -EINVAL;
Nicolas Kaiserce3c8692011-03-04 13:49:41 +0000657 if (len < vnet_hdr_len)
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000658 goto err;
Nicolas Kaiserce3c8692011-03-04 13:49:41 +0000659 len -= vnet_hdr_len;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000660
661 err = memcpy_fromiovecend((void *)&vnet_hdr, iv, 0,
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300662 sizeof(vnet_hdr));
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000663 if (err < 0)
664 goto err;
665 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
666 vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
667 vnet_hdr.hdr_len)
668 vnet_hdr.hdr_len = vnet_hdr.csum_start +
669 vnet_hdr.csum_offset + 2;
670 err = -EINVAL;
671 if (vnet_hdr.hdr_len > len)
672 goto err;
673 }
674
675 err = -EINVAL;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000676 if (unlikely(len < ETH_HLEN))
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000677 goto err;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000678
Jason Wangb92946e2012-05-02 11:42:15 +0800679 err = -EMSGSIZE;
680 if (unlikely(count > UIO_MAXIOV))
681 goto err;
682
Jason Wangece793f2013-07-18 10:55:16 +0800683 if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) {
684 copylen = vnet_hdr.hdr_len ? vnet_hdr.hdr_len : GOODCOPY_LEN;
Jason Wang16a3fa22013-11-13 14:00:40 +0800685 if (copylen > good_linear)
686 copylen = good_linear;
Jason Wang61d46bf2013-07-10 13:43:28 +0800687 linear = copylen;
Jason Wangece793f2013-07-18 10:55:16 +0800688 if (iov_pages(iv, vnet_hdr_len + copylen, count)
689 <= MAX_SKB_FRAGS)
690 zerocopy = true;
691 }
692
693 if (!zerocopy) {
Shirley Ma97bc3632011-07-06 12:26:11 +0000694 copylen = len;
Jason Wang16a3fa22013-11-13 14:00:40 +0800695 if (vnet_hdr.hdr_len > good_linear)
696 linear = good_linear;
697 else
698 linear = vnet_hdr.hdr_len;
Jason Wang61d46bf2013-07-10 13:43:28 +0800699 }
Shirley Ma97bc3632011-07-06 12:26:11 +0000700
701 skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, copylen,
Jason Wang61d46bf2013-07-10 13:43:28 +0800702 linear, noblock, &err);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000703 if (!skb)
704 goto err;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000705
Jason Wang01d66572012-05-02 11:42:06 +0800706 if (zerocopy)
Shirley Ma97bc3632011-07-06 12:26:11 +0000707 err = zerocopy_sg_from_iovec(skb, iv, vnet_hdr_len, count);
Jason Wangece793f2013-07-18 10:55:16 +0800708 else {
Shirley Ma97bc3632011-07-06 12:26:11 +0000709 err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len,
710 len);
Jason Wangece793f2013-07-18 10:55:16 +0800711 if (!err && m && m->msg_control) {
712 struct ubuf_info *uarg = m->msg_control;
713 uarg->callback(uarg, false);
714 }
715 }
716
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000717 if (err)
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000718 goto err_kfree;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000719
720 skb_set_network_header(skb, ETH_HLEN);
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000721 skb_reset_mac_header(skb);
722 skb->protocol = eth_hdr(skb)->h_proto;
723
724 if (vnet_hdr_len) {
725 err = macvtap_skb_from_vnet_hdr(skb, &vnet_hdr);
726 if (err)
727 goto err_kfree;
728 }
729
Jason Wang40893fd2013-03-26 23:11:22 +0000730 skb_probe_transport_header(skb, ETH_HLEN);
Jason Wang9b4d6692013-03-25 20:19:55 +0000731
Vlad Yasevichac4e4af2013-06-25 16:04:20 -0400732 rcu_read_lock();
733 vlan = rcu_dereference(q->vlan);
Shirley Ma97bc3632011-07-06 12:26:11 +0000734 /* copy skb_ubuf_info for callback when skb has no error */
Jason Wang01d66572012-05-02 11:42:06 +0800735 if (zerocopy) {
Shirley Ma97bc3632011-07-06 12:26:11 +0000736 skb_shinfo(skb)->destructor_arg = m->msg_control;
Jason Wang01d66572012-05-02 11:42:06 +0800737 skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
Pravin B Shelarc9af6db2013-02-11 09:27:41 +0000738 skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
Jason Wang01d66572012-05-02 11:42:06 +0800739 }
Eric Dumazet29d79192013-08-08 08:06:14 -0700740 if (vlan) {
Vlad Yasevich6acf54f2013-12-11 13:27:10 -0500741 skb->dev = vlan->dev;
742 dev_queue_xmit(skb);
Eric Dumazet29d79192013-08-08 08:06:14 -0700743 } else {
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000744 kfree_skb(skb);
Eric Dumazet29d79192013-08-08 08:06:14 -0700745 }
Vlad Yasevichac4e4af2013-06-25 16:04:20 -0400746 rcu_read_unlock();
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000747
Shirley Ma97bc3632011-07-06 12:26:11 +0000748 return total_len;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000749
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000750err_kfree:
751 kfree_skb(skb);
752
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000753err:
Vlad Yasevichac4e4af2013-06-25 16:04:20 -0400754 rcu_read_lock();
755 vlan = rcu_dereference(q->vlan);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000756 if (vlan)
Jason Wangcd3e22b2013-11-25 17:19:04 +0800757 this_cpu_inc(vlan->pcpu_stats->tx_dropped);
Vlad Yasevichac4e4af2013-06-25 16:04:20 -0400758 rcu_read_unlock();
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000759
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000760 return err;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000761}
762
763static ssize_t macvtap_aio_write(struct kiocb *iocb, const struct iovec *iv,
764 unsigned long count, loff_t pos)
765{
766 struct file *file = iocb->ki_filp;
767 ssize_t result = -ENOLINK;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000768 struct macvtap_queue *q = file->private_data;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000769
Shirley Ma97bc3632011-07-06 12:26:11 +0000770 result = macvtap_get_user(q, NULL, iv, iov_length(iv, count), count,
771 file->f_flags & O_NONBLOCK);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000772 return result;
773}
774
775/* Put packet to the user space buffer */
776static ssize_t macvtap_put_user(struct macvtap_queue *q,
777 const struct sk_buff *skb,
778 const struct iovec *iv, int len)
779{
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000780 int ret;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000781 int vnet_hdr_len = 0;
Basil Gorf09e2242012-05-03 22:55:24 +0000782 int vlan_offset = 0;
Jason Wangce232ce2013-12-11 13:08:34 +0800783 int copied, total;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000784
785 if (q->flags & IFF_VNET_HDR) {
786 struct virtio_net_hdr vnet_hdr;
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300787 vnet_hdr_len = q->vnet_hdr_sz;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000788 if ((len -= vnet_hdr_len) < 0)
789 return -EINVAL;
790
Zhi Yong Wu359d44d2013-12-07 04:13:04 +0800791 macvtap_skb_to_vnet_hdr(skb, &vnet_hdr);
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000792
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300793 if (memcpy_toiovecend(iv, (void *)&vnet_hdr, 0, sizeof(vnet_hdr)))
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000794 return -EFAULT;
795 }
Jason Wangce232ce2013-12-11 13:08:34 +0800796 total = copied = vnet_hdr_len;
797 total += skb->len;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000798
Basil Gorf09e2242012-05-03 22:55:24 +0000799 if (!vlan_tx_tag_present(skb))
800 len = min_t(int, skb->len, len);
801 else {
802 int copy;
803 struct {
804 __be16 h_vlan_proto;
805 __be16 h_vlan_TCI;
806 } veth;
Jason Wang0fbe0d42013-07-16 13:36:34 +0800807 veth.h_vlan_proto = skb->vlan_proto;
Basil Gorf09e2242012-05-03 22:55:24 +0000808 veth.h_vlan_TCI = htons(vlan_tx_tag_get(skb));
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000809
Basil Gorf09e2242012-05-03 22:55:24 +0000810 vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto);
811 len = min_t(int, skb->len + VLAN_HLEN, len);
Jason Wangce232ce2013-12-11 13:08:34 +0800812 total += VLAN_HLEN;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000813
Basil Gorf09e2242012-05-03 22:55:24 +0000814 copy = min_t(int, vlan_offset, len);
815 ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy);
816 len -= copy;
817 copied += copy;
818 if (ret || !len)
819 goto done;
820
821 copy = min_t(int, sizeof(veth), len);
822 ret = memcpy_toiovecend(iv, (void *)&veth, copied, copy);
823 len -= copy;
824 copied += copy;
825 if (ret || !len)
826 goto done;
827 }
828
829 ret = skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len);
Basil Gorf09e2242012-05-03 22:55:24 +0000830
831done:
Jason Wangce232ce2013-12-11 13:08:34 +0800832 return ret ? ret : total;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000833}
834
Zhi Yong Wu55ec8e22013-12-07 04:13:05 +0800835static ssize_t macvtap_do_read(struct macvtap_queue *q,
Arnd Bergmann501c7742010-02-18 05:46:50 +0000836 const struct iovec *iv, unsigned long len,
837 int noblock)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000838{
Hong zhi guoccf7e722012-06-06 22:36:27 +0000839 DEFINE_WAIT(wait);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000840 struct sk_buff *skb;
Arnd Bergmann501c7742010-02-18 05:46:50 +0000841 ssize_t ret = 0;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000842
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000843 while (len) {
Jason Wang89cee912013-06-05 23:54:34 +0000844 if (!noblock)
845 prepare_to_wait(sk_sleep(&q->sk), &wait,
846 TASK_INTERRUPTIBLE);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000847
848 /* Read frames from the queue */
849 skb = skb_dequeue(&q->sk.sk_receive_queue);
850 if (!skb) {
Arnd Bergmann501c7742010-02-18 05:46:50 +0000851 if (noblock) {
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000852 ret = -EAGAIN;
853 break;
854 }
855 if (signal_pending(current)) {
856 ret = -ERESTARTSYS;
857 break;
858 }
859 /* Nothing to read, let's sleep */
860 schedule();
861 continue;
862 }
863 ret = macvtap_put_user(q, skb, iv, len);
864 kfree_skb(skb);
865 break;
866 }
867
Jason Wang89cee912013-06-05 23:54:34 +0000868 if (!noblock)
869 finish_wait(sk_sleep(&q->sk), &wait);
Arnd Bergmann501c7742010-02-18 05:46:50 +0000870 return ret;
871}
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000872
Arnd Bergmann501c7742010-02-18 05:46:50 +0000873static ssize_t macvtap_aio_read(struct kiocb *iocb, const struct iovec *iv,
874 unsigned long count, loff_t pos)
875{
876 struct file *file = iocb->ki_filp;
877 struct macvtap_queue *q = file->private_data;
878 ssize_t len, ret = 0;
879
880 len = iov_length(iv, count);
881 if (len < 0) {
882 ret = -EINVAL;
883 goto out;
884 }
885
Zhi Yong Wu55ec8e22013-12-07 04:13:05 +0800886 ret = macvtap_do_read(q, iv, len, file->f_flags & O_NONBLOCK);
Jason Wangce232ce2013-12-11 13:08:34 +0800887 ret = min_t(ssize_t, ret, len);
Zhi Yong Wue6ebc7f2013-12-06 14:16:50 +0800888 if (ret > 0)
889 iocb->ki_pos = ret;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000890out:
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000891 return ret;
892}
893
Jason Wang8f475a32013-06-05 23:54:36 +0000894static struct macvlan_dev *macvtap_get_vlan(struct macvtap_queue *q)
895{
896 struct macvlan_dev *vlan;
897
Vlad Yasevich441ac0f2013-06-25 16:04:19 -0400898 ASSERT_RTNL();
899 vlan = rtnl_dereference(q->vlan);
Jason Wang8f475a32013-06-05 23:54:36 +0000900 if (vlan)
901 dev_hold(vlan->dev);
Jason Wang8f475a32013-06-05 23:54:36 +0000902
903 return vlan;
904}
905
906static void macvtap_put_vlan(struct macvlan_dev *vlan)
907{
908 dev_put(vlan->dev);
909}
910
Jason Wang815f2362013-06-05 23:54:39 +0000911static int macvtap_ioctl_set_queue(struct file *file, unsigned int flags)
912{
913 struct macvtap_queue *q = file->private_data;
914 struct macvlan_dev *vlan;
915 int ret;
916
917 vlan = macvtap_get_vlan(q);
918 if (!vlan)
919 return -EINVAL;
920
921 if (flags & IFF_ATTACH_QUEUE)
922 ret = macvtap_enable_queue(vlan->dev, file, q);
923 else if (flags & IFF_DETACH_QUEUE)
924 ret = macvtap_disable_queue(q);
Jason Wangf57855a2013-06-13 14:23:36 +0800925 else
926 ret = -EINVAL;
Jason Wang815f2362013-06-05 23:54:39 +0000927
928 macvtap_put_vlan(vlan);
929 return ret;
930}
931
Vlad Yasevich2be5c762013-06-25 16:04:21 -0400932static int set_offload(struct macvtap_queue *q, unsigned long arg)
933{
934 struct macvlan_dev *vlan;
935 netdev_features_t features;
936 netdev_features_t feature_mask = 0;
937
938 vlan = rtnl_dereference(q->vlan);
939 if (!vlan)
940 return -ENOLINK;
941
942 features = vlan->dev->features;
943
944 if (arg & TUN_F_CSUM) {
945 feature_mask = NETIF_F_HW_CSUM;
946
947 if (arg & (TUN_F_TSO4 | TUN_F_TSO6)) {
948 if (arg & TUN_F_TSO_ECN)
949 feature_mask |= NETIF_F_TSO_ECN;
950 if (arg & TUN_F_TSO4)
951 feature_mask |= NETIF_F_TSO;
952 if (arg & TUN_F_TSO6)
953 feature_mask |= NETIF_F_TSO6;
954 }
955
956 if (arg & TUN_F_UFO)
957 feature_mask |= NETIF_F_UFO;
958 }
959
960 /* tun/tap driver inverts the usage for TSO offloads, where
961 * setting the TSO bit means that the userspace wants to
962 * accept TSO frames and turning it off means that user space
963 * does not support TSO.
964 * For macvtap, we have to invert it to mean the same thing.
965 * When user space turns off TSO, we turn off GSO/LRO so that
966 * user-space will not receive TSO frames.
967 */
968 if (feature_mask & (NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_UFO))
969 features |= RX_OFFLOADS;
970 else
971 features &= ~RX_OFFLOADS;
972
973 /* tap_features are the same as features on tun/tap and
974 * reflect user expectations.
975 */
Vlad Yasevicha567dd62013-08-16 15:25:00 -0400976 vlan->tap_features = feature_mask;
Vlad Yasevich2be5c762013-06-25 16:04:21 -0400977 vlan->set_features = features;
978 netdev_update_features(vlan->dev);
979
980 return 0;
981}
982
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000983/*
984 * provide compatibility with generic tun/tap interface
985 */
986static long macvtap_ioctl(struct file *file, unsigned int cmd,
987 unsigned long arg)
988{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000989 struct macvtap_queue *q = file->private_data;
990 struct macvlan_dev *vlan;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000991 void __user *argp = (void __user *)arg;
992 struct ifreq __user *ifr = argp;
993 unsigned int __user *up = argp;
994 unsigned int u;
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300995 int __user *sp = argp;
996 int s;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000997 int ret;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000998
999 switch (cmd) {
1000 case TUNSETIFF:
1001 /* ignore the name, just look at flags */
1002 if (get_user(u, &ifr->ifr_flags))
1003 return -EFAULT;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +00001004
1005 ret = 0;
Jason Wang815f2362013-06-05 23:54:39 +00001006 if ((u & ~(IFF_VNET_HDR | IFF_MULTI_QUEUE)) !=
1007 (IFF_NO_PI | IFF_TAP))
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +00001008 ret = -EINVAL;
1009 else
1010 q->flags = u;
1011
1012 return ret;
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001013
1014 case TUNGETIFF:
Vlad Yasevich441ac0f2013-06-25 16:04:19 -04001015 rtnl_lock();
Jason Wang8f475a32013-06-05 23:54:36 +00001016 vlan = macvtap_get_vlan(q);
Vlad Yasevich441ac0f2013-06-25 16:04:19 -04001017 if (!vlan) {
1018 rtnl_unlock();
Arnd Bergmann02df55d2010-02-18 05:45:36 +00001019 return -ENOLINK;
Vlad Yasevich441ac0f2013-06-25 16:04:19 -04001020 }
Arnd Bergmann02df55d2010-02-18 05:45:36 +00001021
1022 ret = 0;
Eric Dumazet13707f92011-01-26 19:28:23 +00001023 if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) ||
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +00001024 put_user(q->flags, &ifr->ifr_flags))
Arnd Bergmann02df55d2010-02-18 05:45:36 +00001025 ret = -EFAULT;
Jason Wang8f475a32013-06-05 23:54:36 +00001026 macvtap_put_vlan(vlan);
Vlad Yasevich441ac0f2013-06-25 16:04:19 -04001027 rtnl_unlock();
Arnd Bergmann02df55d2010-02-18 05:45:36 +00001028 return ret;
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001029
Jason Wang815f2362013-06-05 23:54:39 +00001030 case TUNSETQUEUE:
1031 if (get_user(u, &ifr->ifr_flags))
1032 return -EFAULT;
Vlad Yasevich441ac0f2013-06-25 16:04:19 -04001033 rtnl_lock();
1034 ret = macvtap_ioctl_set_queue(file, u);
1035 rtnl_unlock();
Jason Wang82a19eb2013-07-16 13:36:33 +08001036 return ret;
Jason Wang815f2362013-06-05 23:54:39 +00001037
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001038 case TUNGETFEATURES:
Jason Wangdf09b362013-06-05 23:54:40 +00001039 if (put_user(IFF_TAP | IFF_NO_PI | IFF_VNET_HDR |
1040 IFF_MULTI_QUEUE, up))
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001041 return -EFAULT;
1042 return 0;
1043
1044 case TUNSETSNDBUF:
1045 if (get_user(u, up))
1046 return -EFAULT;
1047
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001048 q->sk.sk_sndbuf = u;
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001049 return 0;
1050
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +03001051 case TUNGETVNETHDRSZ:
1052 s = q->vnet_hdr_sz;
1053 if (put_user(s, sp))
1054 return -EFAULT;
1055 return 0;
1056
1057 case TUNSETVNETHDRSZ:
1058 if (get_user(s, sp))
1059 return -EFAULT;
1060 if (s < (int)sizeof(struct virtio_net_hdr))
1061 return -EINVAL;
1062
1063 q->vnet_hdr_sz = s;
1064 return 0;
1065
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001066 case TUNSETOFFLOAD:
1067 /* let the user check for future flags */
1068 if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 |
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +00001069 TUN_F_TSO_ECN | TUN_F_UFO))
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001070 return -EINVAL;
1071
Vlad Yasevich2be5c762013-06-25 16:04:21 -04001072 rtnl_lock();
1073 ret = set_offload(q, arg);
1074 rtnl_unlock();
1075 return ret;
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001076
1077 default:
1078 return -EINVAL;
1079 }
1080}
1081
1082#ifdef CONFIG_COMPAT
1083static long macvtap_compat_ioctl(struct file *file, unsigned int cmd,
1084 unsigned long arg)
1085{
1086 return macvtap_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
1087}
1088#endif
1089
1090static const struct file_operations macvtap_fops = {
1091 .owner = THIS_MODULE,
1092 .open = macvtap_open,
1093 .release = macvtap_release,
1094 .aio_read = macvtap_aio_read,
1095 .aio_write = macvtap_aio_write,
1096 .poll = macvtap_poll,
1097 .llseek = no_llseek,
1098 .unlocked_ioctl = macvtap_ioctl,
1099#ifdef CONFIG_COMPAT
1100 .compat_ioctl = macvtap_compat_ioctl,
1101#endif
1102};
1103
Arnd Bergmann501c7742010-02-18 05:46:50 +00001104static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock,
1105 struct msghdr *m, size_t total_len)
1106{
1107 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
Shirley Ma97bc3632011-07-06 12:26:11 +00001108 return macvtap_get_user(q, m, m->msg_iov, total_len, m->msg_iovlen,
Arnd Bergmann501c7742010-02-18 05:46:50 +00001109 m->msg_flags & MSG_DONTWAIT);
1110}
1111
1112static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock,
1113 struct msghdr *m, size_t total_len,
1114 int flags)
1115{
1116 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
1117 int ret;
1118 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
1119 return -EINVAL;
Zhi Yong Wu55ec8e22013-12-07 04:13:05 +08001120 ret = macvtap_do_read(q, m->msg_iov, total_len,
Arnd Bergmann501c7742010-02-18 05:46:50 +00001121 flags & MSG_DONTWAIT);
David S. Millerde2aa472013-12-10 22:06:18 -05001122 if (ret > total_len) {
1123 m->msg_flags |= MSG_TRUNC;
1124 ret = flags & MSG_TRUNC ? ret : total_len;
1125 }
Arnd Bergmann501c7742010-02-18 05:46:50 +00001126 return ret;
1127}
1128
1129/* Ops structure to mimic raw sockets with tun */
1130static const struct proto_ops macvtap_socket_ops = {
1131 .sendmsg = macvtap_sendmsg,
1132 .recvmsg = macvtap_recvmsg,
1133};
1134
1135/* Get an underlying socket object from tun file. Returns error unless file is
1136 * attached to a device. The returned object works like a packet socket, it
1137 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1138 * holding a reference to the file for as long as the socket is in use. */
1139struct socket *macvtap_get_socket(struct file *file)
1140{
1141 struct macvtap_queue *q;
1142 if (file->f_op != &macvtap_fops)
1143 return ERR_PTR(-EINVAL);
1144 q = file->private_data;
1145 if (!q)
1146 return ERR_PTR(-EBADFD);
1147 return &q->sock;
1148}
1149EXPORT_SYMBOL_GPL(macvtap_get_socket);
1150
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001151static int macvtap_device_event(struct notifier_block *unused,
1152 unsigned long event, void *ptr)
1153{
Jiri Pirko351638e2013-05-28 01:30:21 +00001154 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001155 struct macvlan_dev *vlan;
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001156 struct device *classdev;
1157 dev_t devt;
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001158 int err;
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001159
1160 if (dev->rtnl_link_ops != &macvtap_link_ops)
1161 return NOTIFY_DONE;
1162
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001163 vlan = netdev_priv(dev);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001164
1165 switch (event) {
1166 case NETDEV_REGISTER:
1167 /* Create the device node here after the network device has
1168 * been registered but before register_netdevice has
1169 * finished running.
1170 */
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001171 err = macvtap_get_minor(vlan);
1172 if (err)
1173 return notifier_from_errno(err);
1174
1175 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001176 classdev = device_create(macvtap_class, &dev->dev, devt,
1177 dev, "tap%d", dev->ifindex);
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001178 if (IS_ERR(classdev)) {
1179 macvtap_free_minor(vlan);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001180 return notifier_from_errno(PTR_ERR(classdev));
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001181 }
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001182 break;
1183 case NETDEV_UNREGISTER:
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001184 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001185 device_destroy(macvtap_class, devt);
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001186 macvtap_free_minor(vlan);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001187 break;
1188 }
1189
1190 return NOTIFY_DONE;
1191}
1192
1193static struct notifier_block macvtap_notifier_block __read_mostly = {
1194 .notifier_call = macvtap_device_event,
1195};
1196
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001197static int macvtap_init(void)
1198{
1199 int err;
1200
1201 err = alloc_chrdev_region(&macvtap_major, 0,
1202 MACVTAP_NUM_DEVS, "macvtap");
1203 if (err)
1204 goto out1;
1205
1206 cdev_init(&macvtap_cdev, &macvtap_fops);
1207 err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS);
1208 if (err)
1209 goto out2;
1210
1211 macvtap_class = class_create(THIS_MODULE, "macvtap");
1212 if (IS_ERR(macvtap_class)) {
1213 err = PTR_ERR(macvtap_class);
1214 goto out3;
1215 }
1216
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001217 err = register_netdevice_notifier(&macvtap_notifier_block);
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001218 if (err)
1219 goto out4;
1220
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001221 err = macvlan_link_register(&macvtap_link_ops);
1222 if (err)
1223 goto out5;
1224
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001225 return 0;
1226
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001227out5:
1228 unregister_netdevice_notifier(&macvtap_notifier_block);
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001229out4:
1230 class_unregister(macvtap_class);
1231out3:
1232 cdev_del(&macvtap_cdev);
1233out2:
1234 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1235out1:
1236 return err;
1237}
1238module_init(macvtap_init);
1239
1240static void macvtap_exit(void)
1241{
1242 rtnl_link_unregister(&macvtap_link_ops);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001243 unregister_netdevice_notifier(&macvtap_notifier_block);
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001244 class_unregister(macvtap_class);
1245 cdev_del(&macvtap_cdev);
1246 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1247}
1248module_exit(macvtap_exit);
1249
1250MODULE_ALIAS_RTNL_LINK("macvtap");
1251MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
1252MODULE_LICENSE("GPL");