1 /* 2 * Copyright (c) 2007-2012 Nicira, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 16 * 02110-1301, USA 17 */ 18 19 #include <linux/etherdevice.h> 20 #include <linux/if.h> 21 #include <linux/if_vlan.h> 22 #include <linux/jhash.h> 23 #include <linux/kernel.h> 24 #include <linux/list.h> 25 #include <linux/mutex.h> 26 #include <linux/percpu.h> 27 #include <linux/rcupdate.h> 28 #include <linux/rtnetlink.h> 29 #include <linux/compat.h> 30 #include <net/net_namespace.h> 31 32 #include "datapath.h" 33 #include "vport.h" 34 #include "vport-internal_dev.h" 35 36 /* List of statically compiled vport implementations. Don't forget to also 37 * add yours to the list at the bottom of vport.h. */ 38 static const struct vport_ops *vport_ops_list[] = { 39 &ovs_netdev_vport_ops, 40 &ovs_internal_vport_ops, 41 42 #ifdef CONFIG_OPENVSWITCH_GRE 43 &ovs_gre_vport_ops, 44 #endif 45 #ifdef CONFIG_OPENVSWITCH_VXLAN 46 &ovs_vxlan_vport_ops, 47 #endif 48 }; 49 50 /* Protected by RCU read lock for reading, ovs_mutex for writing. */ 51 static struct hlist_head *dev_table; 52 #define VPORT_HASH_BUCKETS 1024 53 54 /** 55 * ovs_vport_init - initialize vport subsystem 56 * 57 * Called at module load time to initialize the vport subsystem. 58 */ 59 int ovs_vport_init(void) 60 { 61 dev_table = kzalloc(VPORT_HASH_BUCKETS * sizeof(struct hlist_head), 62 GFP_KERNEL); 63 if (!dev_table) 64 return -ENOMEM; 65 66 return 0; 67 } 68 69 /** 70 * ovs_vport_exit - shutdown vport subsystem 71 * 72 * Called at module exit time to shutdown the vport subsystem. 73 */ 74 void ovs_vport_exit(void) 75 { 76 kfree(dev_table); 77 } 78 79 static struct hlist_head *hash_bucket(struct net *net, const char *name) 80 { 81 unsigned int hash = jhash(name, strlen(name), (unsigned long) net); 82 return &dev_table[hash & (VPORT_HASH_BUCKETS - 1)]; 83 } 84 85 /** 86 * ovs_vport_locate - find a port that has already been created 87 * 88 * @name: name of port to find 89 * 90 * Must be called with ovs or RCU read lock. 91 */ 92 struct vport *ovs_vport_locate(struct net *net, const char *name) 93 { 94 struct hlist_head *bucket = hash_bucket(net, name); 95 struct vport *vport; 96 97 hlist_for_each_entry_rcu(vport, bucket, hash_node) 98 if (!strcmp(name, vport->ops->get_name(vport)) && 99 net_eq(ovs_dp_get_net(vport->dp), net)) 100 return vport; 101 102 return NULL; 103 } 104 105 /** 106 * ovs_vport_alloc - allocate and initialize new vport 107 * 108 * @priv_size: Size of private data area to allocate. 109 * @ops: vport device ops 110 * 111 * Allocate and initialize a new vport defined by @ops. The vport will contain 112 * a private data area of size @priv_size that can be accessed using 113 * vport_priv(). vports that are no longer needed should be released with 114 * vport_free(). 115 */ 116 struct vport *ovs_vport_alloc(int priv_size, const struct vport_ops *ops, 117 const struct vport_parms *parms) 118 { 119 struct vport *vport; 120 size_t alloc_size; 121 122 alloc_size = sizeof(struct vport); 123 if (priv_size) { 124 alloc_size = ALIGN(alloc_size, VPORT_ALIGN); 125 alloc_size += priv_size; 126 } 127 128 vport = kzalloc(alloc_size, GFP_KERNEL); 129 if (!vport) 130 return ERR_PTR(-ENOMEM); 131 132 vport->dp = parms->dp; 133 vport->port_no = parms->port_no; 134 vport->upcall_portid = parms->upcall_portid; 135 vport->ops = ops; 136 INIT_HLIST_NODE(&vport->dp_hash_node); 137 138 vport->percpu_stats = alloc_percpu(struct pcpu_tstats); 139 if (!vport->percpu_stats) { 140 kfree(vport); 141 return ERR_PTR(-ENOMEM); 142 } 143 144 spin_lock_init(&vport->stats_lock); 145 146 return vport; 147 } 148 149 /** 150 * ovs_vport_free - uninitialize and free vport 151 * 152 * @vport: vport to free 153 * 154 * Frees a vport allocated with vport_alloc() when it is no longer needed. 155 * 156 * The caller must ensure that an RCU grace period has passed since the last 157 * time @vport was in a datapath. 158 */ 159 void ovs_vport_free(struct vport *vport) 160 { 161 free_percpu(vport->percpu_stats); 162 kfree(vport); 163 } 164 165 /** 166 * ovs_vport_add - add vport device (for kernel callers) 167 * 168 * @parms: Information about new vport. 169 * 170 * Creates a new vport with the specified configuration (which is dependent on 171 * device type). ovs_mutex must be held. 172 */ 173 struct vport *ovs_vport_add(const struct vport_parms *parms) 174 { 175 struct vport *vport; 176 int err = 0; 177 int i; 178 179 for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) { 180 if (vport_ops_list[i]->type == parms->type) { 181 struct hlist_head *bucket; 182 183 vport = vport_ops_list[i]->create(parms); 184 if (IS_ERR(vport)) { 185 err = PTR_ERR(vport); 186 goto out; 187 } 188 189 bucket = hash_bucket(ovs_dp_get_net(vport->dp), 190 vport->ops->get_name(vport)); 191 hlist_add_head_rcu(&vport->hash_node, bucket); 192 return vport; 193 } 194 } 195 196 err = -EAFNOSUPPORT; 197 198 out: 199 return ERR_PTR(err); 200 } 201 202 /** 203 * ovs_vport_set_options - modify existing vport device (for kernel callers) 204 * 205 * @vport: vport to modify. 206 * @options: New configuration. 207 * 208 * Modifies an existing device with the specified configuration (which is 209 * dependent on device type). ovs_mutex must be held. 210 */ 211 int ovs_vport_set_options(struct vport *vport, struct nlattr *options) 212 { 213 if (!vport->ops->set_options) 214 return -EOPNOTSUPP; 215 return vport->ops->set_options(vport, options); 216 } 217 218 /** 219 * ovs_vport_del - delete existing vport device 220 * 221 * @vport: vport to delete. 222 * 223 * Detaches @vport from its datapath and destroys it. It is possible to fail 224 * for reasons such as lack of memory. ovs_mutex must be held. 225 */ 226 void ovs_vport_del(struct vport *vport) 227 { 228 ASSERT_OVSL(); 229 230 hlist_del_rcu(&vport->hash_node); 231 232 vport->ops->destroy(vport); 233 } 234 235 /** 236 * ovs_vport_get_stats - retrieve device stats 237 * 238 * @vport: vport from which to retrieve the stats 239 * @stats: location to store stats 240 * 241 * Retrieves transmit, receive, and error stats for the given device. 242 * 243 * Must be called with ovs_mutex or rcu_read_lock. 244 */ 245 void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats) 246 { 247 int i; 248 249 memset(stats, 0, sizeof(*stats)); 250 251 /* We potentially have 2 sources of stats that need to be combined: 252 * those we have collected (split into err_stats and percpu_stats) from 253 * set_stats() and device error stats from netdev->get_stats() (for 254 * errors that happen downstream and therefore aren't reported through 255 * our vport_record_error() function). 256 * Stats from first source are reported by ovs (OVS_VPORT_ATTR_STATS). 257 * netdev-stats can be directly read over netlink-ioctl. 258 */ 259 260 spin_lock_bh(&vport->stats_lock); 261 262 stats->rx_errors = vport->err_stats.rx_errors; 263 stats->tx_errors = vport->err_stats.tx_errors; 264 stats->tx_dropped = vport->err_stats.tx_dropped; 265 stats->rx_dropped = vport->err_stats.rx_dropped; 266 267 spin_unlock_bh(&vport->stats_lock); 268 269 for_each_possible_cpu(i) { 270 const struct pcpu_tstats *percpu_stats; 271 struct pcpu_tstats local_stats; 272 unsigned int start; 273 274 percpu_stats = per_cpu_ptr(vport->percpu_stats, i); 275 276 do { 277 start = u64_stats_fetch_begin_bh(&percpu_stats->syncp); 278 local_stats = *percpu_stats; 279 } while (u64_stats_fetch_retry_bh(&percpu_stats->syncp, start)); 280 281 stats->rx_bytes += local_stats.rx_bytes; 282 stats->rx_packets += local_stats.rx_packets; 283 stats->tx_bytes += local_stats.tx_bytes; 284 stats->tx_packets += local_stats.tx_packets; 285 } 286 } 287 288 /** 289 * ovs_vport_get_options - retrieve device options 290 * 291 * @vport: vport from which to retrieve the options. 292 * @skb: sk_buff where options should be appended. 293 * 294 * Retrieves the configuration of the given device, appending an 295 * %OVS_VPORT_ATTR_OPTIONS attribute that in turn contains nested 296 * vport-specific attributes to @skb. 297 * 298 * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room, or another 299 * negative error code if a real error occurred. If an error occurs, @skb is 300 * left unmodified. 301 * 302 * Must be called with ovs_mutex or rcu_read_lock. 303 */ 304 int ovs_vport_get_options(const struct vport *vport, struct sk_buff *skb) 305 { 306 struct nlattr *nla; 307 int err; 308 309 if (!vport->ops->get_options) 310 return 0; 311 312 nla = nla_nest_start(skb, OVS_VPORT_ATTR_OPTIONS); 313 if (!nla) 314 return -EMSGSIZE; 315 316 err = vport->ops->get_options(vport, skb); 317 if (err) { 318 nla_nest_cancel(skb, nla); 319 return err; 320 } 321 322 nla_nest_end(skb, nla); 323 return 0; 324 } 325 326 /** 327 * ovs_vport_receive - pass up received packet to the datapath for processing 328 * 329 * @vport: vport that received the packet 330 * @skb: skb that was received 331 * @tun_key: tunnel (if any) that carried packet 332 * 333 * Must be called with rcu_read_lock. The packet cannot be shared and 334 * skb->data should point to the Ethernet header. 335 */ 336 void ovs_vport_receive(struct vport *vport, struct sk_buff *skb, 337 struct ovs_key_ipv4_tunnel *tun_key) 338 { 339 struct pcpu_tstats *stats; 340 341 stats = this_cpu_ptr(vport->percpu_stats); 342 u64_stats_update_begin(&stats->syncp); 343 stats->rx_packets++; 344 stats->rx_bytes += skb->len; 345 u64_stats_update_end(&stats->syncp); 346 347 OVS_CB(skb)->tun_key = tun_key; 348 ovs_dp_process_received_packet(vport, skb); 349 } 350 351 /** 352 * ovs_vport_send - send a packet on a device 353 * 354 * @vport: vport on which to send the packet 355 * @skb: skb to send 356 * 357 * Sends the given packet and returns the length of data sent. Either ovs 358 * lock or rcu_read_lock must be held. 359 */ 360 int ovs_vport_send(struct vport *vport, struct sk_buff *skb) 361 { 362 int sent = vport->ops->send(vport, skb); 363 364 if (likely(sent > 0)) { 365 struct pcpu_tstats *stats; 366 367 stats = this_cpu_ptr(vport->percpu_stats); 368 369 u64_stats_update_begin(&stats->syncp); 370 stats->tx_packets++; 371 stats->tx_bytes += sent; 372 u64_stats_update_end(&stats->syncp); 373 } else if (sent < 0) { 374 ovs_vport_record_error(vport, VPORT_E_TX_ERROR); 375 kfree_skb(skb); 376 } else 377 ovs_vport_record_error(vport, VPORT_E_TX_DROPPED); 378 379 return sent; 380 } 381 382 /** 383 * ovs_vport_record_error - indicate device error to generic stats layer 384 * 385 * @vport: vport that encountered the error 386 * @err_type: one of enum vport_err_type types to indicate the error type 387 * 388 * If using the vport generic stats layer indicate that an error of the given 389 * type has occurred. 390 */ 391 void ovs_vport_record_error(struct vport *vport, enum vport_err_type err_type) 392 { 393 spin_lock(&vport->stats_lock); 394 395 switch (err_type) { 396 case VPORT_E_RX_DROPPED: 397 vport->err_stats.rx_dropped++; 398 break; 399 400 case VPORT_E_RX_ERROR: 401 vport->err_stats.rx_errors++; 402 break; 403 404 case VPORT_E_TX_DROPPED: 405 vport->err_stats.tx_dropped++; 406 break; 407 408 case VPORT_E_TX_ERROR: 409 vport->err_stats.tx_errors++; 410 break; 411 } 412 413 spin_unlock(&vport->stats_lock); 414 } 415 416 static void free_vport_rcu(struct rcu_head *rcu) 417 { 418 struct vport *vport = container_of(rcu, struct vport, rcu); 419 420 ovs_vport_free(vport); 421 } 422 423 void ovs_vport_deferred_free(struct vport *vport) 424 { 425 if (!vport) 426 return; 427 428 call_rcu(&vport->rcu, free_vport_rcu); 429 } 430