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 static void ovs_vport_record_error(struct vport *, 37 enum vport_err_type err_type); 38 39 /* List of statically compiled vport implementations. Don't forget to also 40 * add yours to the list at the bottom of vport.h. */ 41 static const struct vport_ops *vport_ops_list[] = { 42 &ovs_netdev_vport_ops, 43 &ovs_internal_vport_ops, 44 45 #ifdef CONFIG_OPENVSWITCH_GRE 46 &ovs_gre_vport_ops, 47 #endif 48 #ifdef CONFIG_OPENVSWITCH_VXLAN 49 &ovs_vxlan_vport_ops, 50 #endif 51 }; 52 53 /* Protected by RCU read lock for reading, ovs_mutex for writing. */ 54 static struct hlist_head *dev_table; 55 #define VPORT_HASH_BUCKETS 1024 56 57 /** 58 * ovs_vport_init - initialize vport subsystem 59 * 60 * Called at module load time to initialize the vport subsystem. 61 */ 62 int ovs_vport_init(void) 63 { 64 dev_table = kzalloc(VPORT_HASH_BUCKETS * sizeof(struct hlist_head), 65 GFP_KERNEL); 66 if (!dev_table) 67 return -ENOMEM; 68 69 return 0; 70 } 71 72 /** 73 * ovs_vport_exit - shutdown vport subsystem 74 * 75 * Called at module exit time to shutdown the vport subsystem. 76 */ 77 void ovs_vport_exit(void) 78 { 79 kfree(dev_table); 80 } 81 82 static struct hlist_head *hash_bucket(struct net *net, const char *name) 83 { 84 unsigned int hash = jhash(name, strlen(name), (unsigned long) net); 85 return &dev_table[hash & (VPORT_HASH_BUCKETS - 1)]; 86 } 87 88 /** 89 * ovs_vport_locate - find a port that has already been created 90 * 91 * @name: name of port to find 92 * 93 * Must be called with ovs or RCU read lock. 94 */ 95 struct vport *ovs_vport_locate(struct net *net, const char *name) 96 { 97 struct hlist_head *bucket = hash_bucket(net, name); 98 struct vport *vport; 99 100 hlist_for_each_entry_rcu(vport, bucket, hash_node) 101 if (!strcmp(name, vport->ops->get_name(vport)) && 102 net_eq(ovs_dp_get_net(vport->dp), net)) 103 return vport; 104 105 return NULL; 106 } 107 108 /** 109 * ovs_vport_alloc - allocate and initialize new vport 110 * 111 * @priv_size: Size of private data area to allocate. 112 * @ops: vport device ops 113 * 114 * Allocate and initialize a new vport defined by @ops. The vport will contain 115 * a private data area of size @priv_size that can be accessed using 116 * vport_priv(). vports that are no longer needed should be released with 117 * vport_free(). 118 */ 119 struct vport *ovs_vport_alloc(int priv_size, const struct vport_ops *ops, 120 const struct vport_parms *parms) 121 { 122 struct vport *vport; 123 size_t alloc_size; 124 int i; 125 126 alloc_size = sizeof(struct vport); 127 if (priv_size) { 128 alloc_size = ALIGN(alloc_size, VPORT_ALIGN); 129 alloc_size += priv_size; 130 } 131 132 vport = kzalloc(alloc_size, GFP_KERNEL); 133 if (!vport) 134 return ERR_PTR(-ENOMEM); 135 136 vport->dp = parms->dp; 137 vport->port_no = parms->port_no; 138 vport->upcall_portid = parms->upcall_portid; 139 vport->ops = ops; 140 INIT_HLIST_NODE(&vport->dp_hash_node); 141 142 vport->percpu_stats = alloc_percpu(struct pcpu_sw_netstats); 143 if (!vport->percpu_stats) { 144 kfree(vport); 145 return ERR_PTR(-ENOMEM); 146 } 147 148 for_each_possible_cpu(i) { 149 struct pcpu_sw_netstats *vport_stats; 150 vport_stats = per_cpu_ptr(vport->percpu_stats, i); 151 u64_stats_init(&vport_stats->syncp); 152 } 153 154 155 spin_lock_init(&vport->stats_lock); 156 157 return vport; 158 } 159 160 /** 161 * ovs_vport_free - uninitialize and free vport 162 * 163 * @vport: vport to free 164 * 165 * Frees a vport allocated with vport_alloc() when it is no longer needed. 166 * 167 * The caller must ensure that an RCU grace period has passed since the last 168 * time @vport was in a datapath. 169 */ 170 void ovs_vport_free(struct vport *vport) 171 { 172 free_percpu(vport->percpu_stats); 173 kfree(vport); 174 } 175 176 /** 177 * ovs_vport_add - add vport device (for kernel callers) 178 * 179 * @parms: Information about new vport. 180 * 181 * Creates a new vport with the specified configuration (which is dependent on 182 * device type). ovs_mutex must be held. 183 */ 184 struct vport *ovs_vport_add(const struct vport_parms *parms) 185 { 186 struct vport *vport; 187 int err = 0; 188 int i; 189 190 for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) { 191 if (vport_ops_list[i]->type == parms->type) { 192 struct hlist_head *bucket; 193 194 vport = vport_ops_list[i]->create(parms); 195 if (IS_ERR(vport)) { 196 err = PTR_ERR(vport); 197 goto out; 198 } 199 200 bucket = hash_bucket(ovs_dp_get_net(vport->dp), 201 vport->ops->get_name(vport)); 202 hlist_add_head_rcu(&vport->hash_node, bucket); 203 return vport; 204 } 205 } 206 207 err = -EAFNOSUPPORT; 208 209 out: 210 return ERR_PTR(err); 211 } 212 213 /** 214 * ovs_vport_set_options - modify existing vport device (for kernel callers) 215 * 216 * @vport: vport to modify. 217 * @options: New configuration. 218 * 219 * Modifies an existing device with the specified configuration (which is 220 * dependent on device type). ovs_mutex must be held. 221 */ 222 int ovs_vport_set_options(struct vport *vport, struct nlattr *options) 223 { 224 if (!vport->ops->set_options) 225 return -EOPNOTSUPP; 226 return vport->ops->set_options(vport, options); 227 } 228 229 /** 230 * ovs_vport_del - delete existing vport device 231 * 232 * @vport: vport to delete. 233 * 234 * Detaches @vport from its datapath and destroys it. It is possible to fail 235 * for reasons such as lack of memory. ovs_mutex must be held. 236 */ 237 void ovs_vport_del(struct vport *vport) 238 { 239 ASSERT_OVSL(); 240 241 hlist_del_rcu(&vport->hash_node); 242 243 vport->ops->destroy(vport); 244 } 245 246 /** 247 * ovs_vport_get_stats - retrieve device stats 248 * 249 * @vport: vport from which to retrieve the stats 250 * @stats: location to store stats 251 * 252 * Retrieves transmit, receive, and error stats for the given device. 253 * 254 * Must be called with ovs_mutex or rcu_read_lock. 255 */ 256 void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats) 257 { 258 int i; 259 260 memset(stats, 0, sizeof(*stats)); 261 262 /* We potentially have 2 sources of stats that need to be combined: 263 * those we have collected (split into err_stats and percpu_stats) from 264 * set_stats() and device error stats from netdev->get_stats() (for 265 * errors that happen downstream and therefore aren't reported through 266 * our vport_record_error() function). 267 * Stats from first source are reported by ovs (OVS_VPORT_ATTR_STATS). 268 * netdev-stats can be directly read over netlink-ioctl. 269 */ 270 271 spin_lock_bh(&vport->stats_lock); 272 273 stats->rx_errors = vport->err_stats.rx_errors; 274 stats->tx_errors = vport->err_stats.tx_errors; 275 stats->tx_dropped = vport->err_stats.tx_dropped; 276 stats->rx_dropped = vport->err_stats.rx_dropped; 277 278 spin_unlock_bh(&vport->stats_lock); 279 280 for_each_possible_cpu(i) { 281 const struct pcpu_sw_netstats *percpu_stats; 282 struct pcpu_sw_netstats local_stats; 283 unsigned int start; 284 285 percpu_stats = per_cpu_ptr(vport->percpu_stats, i); 286 287 do { 288 start = u64_stats_fetch_begin_bh(&percpu_stats->syncp); 289 local_stats = *percpu_stats; 290 } while (u64_stats_fetch_retry_bh(&percpu_stats->syncp, start)); 291 292 stats->rx_bytes += local_stats.rx_bytes; 293 stats->rx_packets += local_stats.rx_packets; 294 stats->tx_bytes += local_stats.tx_bytes; 295 stats->tx_packets += local_stats.tx_packets; 296 } 297 } 298 299 /** 300 * ovs_vport_get_options - retrieve device options 301 * 302 * @vport: vport from which to retrieve the options. 303 * @skb: sk_buff where options should be appended. 304 * 305 * Retrieves the configuration of the given device, appending an 306 * %OVS_VPORT_ATTR_OPTIONS attribute that in turn contains nested 307 * vport-specific attributes to @skb. 308 * 309 * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room, or another 310 * negative error code if a real error occurred. If an error occurs, @skb is 311 * left unmodified. 312 * 313 * Must be called with ovs_mutex or rcu_read_lock. 314 */ 315 int ovs_vport_get_options(const struct vport *vport, struct sk_buff *skb) 316 { 317 struct nlattr *nla; 318 int err; 319 320 if (!vport->ops->get_options) 321 return 0; 322 323 nla = nla_nest_start(skb, OVS_VPORT_ATTR_OPTIONS); 324 if (!nla) 325 return -EMSGSIZE; 326 327 err = vport->ops->get_options(vport, skb); 328 if (err) { 329 nla_nest_cancel(skb, nla); 330 return err; 331 } 332 333 nla_nest_end(skb, nla); 334 return 0; 335 } 336 337 /** 338 * ovs_vport_receive - pass up received packet to the datapath for processing 339 * 340 * @vport: vport that received the packet 341 * @skb: skb that was received 342 * @tun_key: tunnel (if any) that carried packet 343 * 344 * Must be called with rcu_read_lock. The packet cannot be shared and 345 * skb->data should point to the Ethernet header. 346 */ 347 void ovs_vport_receive(struct vport *vport, struct sk_buff *skb, 348 struct ovs_key_ipv4_tunnel *tun_key) 349 { 350 struct pcpu_sw_netstats *stats; 351 352 stats = this_cpu_ptr(vport->percpu_stats); 353 u64_stats_update_begin(&stats->syncp); 354 stats->rx_packets++; 355 stats->rx_bytes += skb->len; 356 u64_stats_update_end(&stats->syncp); 357 358 OVS_CB(skb)->tun_key = tun_key; 359 ovs_dp_process_received_packet(vport, skb); 360 } 361 362 /** 363 * ovs_vport_send - send a packet on a device 364 * 365 * @vport: vport on which to send the packet 366 * @skb: skb to send 367 * 368 * Sends the given packet and returns the length of data sent. Either ovs 369 * lock or rcu_read_lock must be held. 370 */ 371 int ovs_vport_send(struct vport *vport, struct sk_buff *skb) 372 { 373 int sent = vport->ops->send(vport, skb); 374 375 if (likely(sent > 0)) { 376 struct pcpu_sw_netstats *stats; 377 378 stats = this_cpu_ptr(vport->percpu_stats); 379 380 u64_stats_update_begin(&stats->syncp); 381 stats->tx_packets++; 382 stats->tx_bytes += sent; 383 u64_stats_update_end(&stats->syncp); 384 } else if (sent < 0) { 385 ovs_vport_record_error(vport, VPORT_E_TX_ERROR); 386 kfree_skb(skb); 387 } else 388 ovs_vport_record_error(vport, VPORT_E_TX_DROPPED); 389 390 return sent; 391 } 392 393 /** 394 * ovs_vport_record_error - indicate device error to generic stats layer 395 * 396 * @vport: vport that encountered the error 397 * @err_type: one of enum vport_err_type types to indicate the error type 398 * 399 * If using the vport generic stats layer indicate that an error of the given 400 * type has occurred. 401 */ 402 static void ovs_vport_record_error(struct vport *vport, 403 enum vport_err_type err_type) 404 { 405 spin_lock(&vport->stats_lock); 406 407 switch (err_type) { 408 case VPORT_E_RX_DROPPED: 409 vport->err_stats.rx_dropped++; 410 break; 411 412 case VPORT_E_RX_ERROR: 413 vport->err_stats.rx_errors++; 414 break; 415 416 case VPORT_E_TX_DROPPED: 417 vport->err_stats.tx_dropped++; 418 break; 419 420 case VPORT_E_TX_ERROR: 421 vport->err_stats.tx_errors++; 422 break; 423 } 424 425 spin_unlock(&vport->stats_lock); 426 } 427 428 static void free_vport_rcu(struct rcu_head *rcu) 429 { 430 struct vport *vport = container_of(rcu, struct vport, rcu); 431 432 ovs_vport_free(vport); 433 } 434 435 void ovs_vport_deferred_free(struct vport *vport) 436 { 437 if (!vport) 438 return; 439 440 call_rcu(&vport->rcu, free_vport_rcu); 441 } 442