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 int i; 122 123 alloc_size = sizeof(struct vport); 124 if (priv_size) { 125 alloc_size = ALIGN(alloc_size, VPORT_ALIGN); 126 alloc_size += priv_size; 127 } 128 129 vport = kzalloc(alloc_size, GFP_KERNEL); 130 if (!vport) 131 return ERR_PTR(-ENOMEM); 132 133 vport->dp = parms->dp; 134 vport->port_no = parms->port_no; 135 vport->upcall_portid = parms->upcall_portid; 136 vport->ops = ops; 137 INIT_HLIST_NODE(&vport->dp_hash_node); 138 139 vport->percpu_stats = alloc_percpu(struct pcpu_tstats); 140 if (!vport->percpu_stats) { 141 kfree(vport); 142 return ERR_PTR(-ENOMEM); 143 } 144 145 for_each_possible_cpu(i) { 146 struct pcpu_tstats *vport_stats; 147 vport_stats = per_cpu_ptr(vport->percpu_stats, i); 148 u64_stats_init(&vport_stats->syncp); 149 } 150 151 152 spin_lock_init(&vport->stats_lock); 153 154 return vport; 155 } 156 157 /** 158 * ovs_vport_free - uninitialize and free vport 159 * 160 * @vport: vport to free 161 * 162 * Frees a vport allocated with vport_alloc() when it is no longer needed. 163 * 164 * The caller must ensure that an RCU grace period has passed since the last 165 * time @vport was in a datapath. 166 */ 167 void ovs_vport_free(struct vport *vport) 168 { 169 free_percpu(vport->percpu_stats); 170 kfree(vport); 171 } 172 173 /** 174 * ovs_vport_add - add vport device (for kernel callers) 175 * 176 * @parms: Information about new vport. 177 * 178 * Creates a new vport with the specified configuration (which is dependent on 179 * device type). ovs_mutex must be held. 180 */ 181 struct vport *ovs_vport_add(const struct vport_parms *parms) 182 { 183 struct vport *vport; 184 int err = 0; 185 int i; 186 187 for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) { 188 if (vport_ops_list[i]->type == parms->type) { 189 struct hlist_head *bucket; 190 191 vport = vport_ops_list[i]->create(parms); 192 if (IS_ERR(vport)) { 193 err = PTR_ERR(vport); 194 goto out; 195 } 196 197 bucket = hash_bucket(ovs_dp_get_net(vport->dp), 198 vport->ops->get_name(vport)); 199 hlist_add_head_rcu(&vport->hash_node, bucket); 200 return vport; 201 } 202 } 203 204 err = -EAFNOSUPPORT; 205 206 out: 207 return ERR_PTR(err); 208 } 209 210 /** 211 * ovs_vport_set_options - modify existing vport device (for kernel callers) 212 * 213 * @vport: vport to modify. 214 * @options: New configuration. 215 * 216 * Modifies an existing device with the specified configuration (which is 217 * dependent on device type). ovs_mutex must be held. 218 */ 219 int ovs_vport_set_options(struct vport *vport, struct nlattr *options) 220 { 221 if (!vport->ops->set_options) 222 return -EOPNOTSUPP; 223 return vport->ops->set_options(vport, options); 224 } 225 226 /** 227 * ovs_vport_del - delete existing vport device 228 * 229 * @vport: vport to delete. 230 * 231 * Detaches @vport from its datapath and destroys it. It is possible to fail 232 * for reasons such as lack of memory. ovs_mutex must be held. 233 */ 234 void ovs_vport_del(struct vport *vport) 235 { 236 ASSERT_OVSL(); 237 238 hlist_del_rcu(&vport->hash_node); 239 240 vport->ops->destroy(vport); 241 } 242 243 /** 244 * ovs_vport_get_stats - retrieve device stats 245 * 246 * @vport: vport from which to retrieve the stats 247 * @stats: location to store stats 248 * 249 * Retrieves transmit, receive, and error stats for the given device. 250 * 251 * Must be called with ovs_mutex or rcu_read_lock. 252 */ 253 void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats) 254 { 255 int i; 256 257 memset(stats, 0, sizeof(*stats)); 258 259 /* We potentially have 2 sources of stats that need to be combined: 260 * those we have collected (split into err_stats and percpu_stats) from 261 * set_stats() and device error stats from netdev->get_stats() (for 262 * errors that happen downstream and therefore aren't reported through 263 * our vport_record_error() function). 264 * Stats from first source are reported by ovs (OVS_VPORT_ATTR_STATS). 265 * netdev-stats can be directly read over netlink-ioctl. 266 */ 267 268 spin_lock_bh(&vport->stats_lock); 269 270 stats->rx_errors = vport->err_stats.rx_errors; 271 stats->tx_errors = vport->err_stats.tx_errors; 272 stats->tx_dropped = vport->err_stats.tx_dropped; 273 stats->rx_dropped = vport->err_stats.rx_dropped; 274 275 spin_unlock_bh(&vport->stats_lock); 276 277 for_each_possible_cpu(i) { 278 const struct pcpu_tstats *percpu_stats; 279 struct pcpu_tstats local_stats; 280 unsigned int start; 281 282 percpu_stats = per_cpu_ptr(vport->percpu_stats, i); 283 284 do { 285 start = u64_stats_fetch_begin_bh(&percpu_stats->syncp); 286 local_stats = *percpu_stats; 287 } while (u64_stats_fetch_retry_bh(&percpu_stats->syncp, start)); 288 289 stats->rx_bytes += local_stats.rx_bytes; 290 stats->rx_packets += local_stats.rx_packets; 291 stats->tx_bytes += local_stats.tx_bytes; 292 stats->tx_packets += local_stats.tx_packets; 293 } 294 } 295 296 /** 297 * ovs_vport_get_options - retrieve device options 298 * 299 * @vport: vport from which to retrieve the options. 300 * @skb: sk_buff where options should be appended. 301 * 302 * Retrieves the configuration of the given device, appending an 303 * %OVS_VPORT_ATTR_OPTIONS attribute that in turn contains nested 304 * vport-specific attributes to @skb. 305 * 306 * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room, or another 307 * negative error code if a real error occurred. If an error occurs, @skb is 308 * left unmodified. 309 * 310 * Must be called with ovs_mutex or rcu_read_lock. 311 */ 312 int ovs_vport_get_options(const struct vport *vport, struct sk_buff *skb) 313 { 314 struct nlattr *nla; 315 int err; 316 317 if (!vport->ops->get_options) 318 return 0; 319 320 nla = nla_nest_start(skb, OVS_VPORT_ATTR_OPTIONS); 321 if (!nla) 322 return -EMSGSIZE; 323 324 err = vport->ops->get_options(vport, skb); 325 if (err) { 326 nla_nest_cancel(skb, nla); 327 return err; 328 } 329 330 nla_nest_end(skb, nla); 331 return 0; 332 } 333 334 /** 335 * ovs_vport_receive - pass up received packet to the datapath for processing 336 * 337 * @vport: vport that received the packet 338 * @skb: skb that was received 339 * @tun_key: tunnel (if any) that carried packet 340 * 341 * Must be called with rcu_read_lock. The packet cannot be shared and 342 * skb->data should point to the Ethernet header. 343 */ 344 void ovs_vport_receive(struct vport *vport, struct sk_buff *skb, 345 struct ovs_key_ipv4_tunnel *tun_key) 346 { 347 struct pcpu_tstats *stats; 348 349 stats = this_cpu_ptr(vport->percpu_stats); 350 u64_stats_update_begin(&stats->syncp); 351 stats->rx_packets++; 352 stats->rx_bytes += skb->len; 353 u64_stats_update_end(&stats->syncp); 354 355 OVS_CB(skb)->tun_key = tun_key; 356 ovs_dp_process_received_packet(vport, skb); 357 } 358 359 /** 360 * ovs_vport_send - send a packet on a device 361 * 362 * @vport: vport on which to send the packet 363 * @skb: skb to send 364 * 365 * Sends the given packet and returns the length of data sent. Either ovs 366 * lock or rcu_read_lock must be held. 367 */ 368 int ovs_vport_send(struct vport *vport, struct sk_buff *skb) 369 { 370 int sent = vport->ops->send(vport, skb); 371 372 if (likely(sent > 0)) { 373 struct pcpu_tstats *stats; 374 375 stats = this_cpu_ptr(vport->percpu_stats); 376 377 u64_stats_update_begin(&stats->syncp); 378 stats->tx_packets++; 379 stats->tx_bytes += sent; 380 u64_stats_update_end(&stats->syncp); 381 } else if (sent < 0) { 382 ovs_vport_record_error(vport, VPORT_E_TX_ERROR); 383 kfree_skb(skb); 384 } else 385 ovs_vport_record_error(vport, VPORT_E_TX_DROPPED); 386 387 return sent; 388 } 389 390 /** 391 * ovs_vport_record_error - indicate device error to generic stats layer 392 * 393 * @vport: vport that encountered the error 394 * @err_type: one of enum vport_err_type types to indicate the error type 395 * 396 * If using the vport generic stats layer indicate that an error of the given 397 * type has occurred. 398 */ 399 void ovs_vport_record_error(struct vport *vport, enum vport_err_type err_type) 400 { 401 spin_lock(&vport->stats_lock); 402 403 switch (err_type) { 404 case VPORT_E_RX_DROPPED: 405 vport->err_stats.rx_dropped++; 406 break; 407 408 case VPORT_E_RX_ERROR: 409 vport->err_stats.rx_errors++; 410 break; 411 412 case VPORT_E_TX_DROPPED: 413 vport->err_stats.tx_dropped++; 414 break; 415 416 case VPORT_E_TX_ERROR: 417 vport->err_stats.tx_errors++; 418 break; 419 } 420 421 spin_unlock(&vport->stats_lock); 422 } 423 424 static void free_vport_rcu(struct rcu_head *rcu) 425 { 426 struct vport *vport = container_of(rcu, struct vport, rcu); 427 428 ovs_vport_free(vport); 429 } 430 431 void ovs_vport_deferred_free(struct vport *vport) 432 { 433 if (!vport) 434 return; 435 436 call_rcu(&vport->rcu, free_vport_rcu); 437 } 438