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; 124 125 alloc_size = sizeof(struct vport); 126 if (priv_size) { 127 alloc_size = ALIGN(alloc_size, VPORT_ALIGN); 128 alloc_size += priv_size; 129 } 130 131 vport = kzalloc(alloc_size, GFP_KERNEL); 132 if (!vport) 133 return ERR_PTR(-ENOMEM); 134 135 vport->dp = parms->dp; 136 vport->port_no = parms->port_no; 137 vport->upcall_portid = parms->upcall_portid; 138 vport->ops = ops; 139 INIT_HLIST_NODE(&vport->dp_hash_node); 140 141 vport->percpu_stats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 142 if (!vport->percpu_stats) { 143 kfree(vport); 144 return ERR_PTR(-ENOMEM); 145 } 146 147 spin_lock_init(&vport->stats_lock); 148 149 return vport; 150 } 151 152 /** 153 * ovs_vport_free - uninitialize and free vport 154 * 155 * @vport: vport to free 156 * 157 * Frees a vport allocated with vport_alloc() when it is no longer needed. 158 * 159 * The caller must ensure that an RCU grace period has passed since the last 160 * time @vport was in a datapath. 161 */ 162 void ovs_vport_free(struct vport *vport) 163 { 164 free_percpu(vport->percpu_stats); 165 kfree(vport); 166 } 167 168 /** 169 * ovs_vport_add - add vport device (for kernel callers) 170 * 171 * @parms: Information about new vport. 172 * 173 * Creates a new vport with the specified configuration (which is dependent on 174 * device type). ovs_mutex must be held. 175 */ 176 struct vport *ovs_vport_add(const struct vport_parms *parms) 177 { 178 struct vport *vport; 179 int err = 0; 180 int i; 181 182 for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) { 183 if (vport_ops_list[i]->type == parms->type) { 184 struct hlist_head *bucket; 185 186 vport = vport_ops_list[i]->create(parms); 187 if (IS_ERR(vport)) { 188 err = PTR_ERR(vport); 189 goto out; 190 } 191 192 bucket = hash_bucket(ovs_dp_get_net(vport->dp), 193 vport->ops->get_name(vport)); 194 hlist_add_head_rcu(&vport->hash_node, bucket); 195 return vport; 196 } 197 } 198 199 err = -EAFNOSUPPORT; 200 201 out: 202 return ERR_PTR(err); 203 } 204 205 /** 206 * ovs_vport_set_options - modify existing vport device (for kernel callers) 207 * 208 * @vport: vport to modify. 209 * @options: New configuration. 210 * 211 * Modifies an existing device with the specified configuration (which is 212 * dependent on device type). ovs_mutex must be held. 213 */ 214 int ovs_vport_set_options(struct vport *vport, struct nlattr *options) 215 { 216 if (!vport->ops->set_options) 217 return -EOPNOTSUPP; 218 return vport->ops->set_options(vport, options); 219 } 220 221 /** 222 * ovs_vport_del - delete existing vport device 223 * 224 * @vport: vport to delete. 225 * 226 * Detaches @vport from its datapath and destroys it. It is possible to fail 227 * for reasons such as lack of memory. ovs_mutex must be held. 228 */ 229 void ovs_vport_del(struct vport *vport) 230 { 231 ASSERT_OVSL(); 232 233 hlist_del_rcu(&vport->hash_node); 234 235 vport->ops->destroy(vport); 236 } 237 238 /** 239 * ovs_vport_get_stats - retrieve device stats 240 * 241 * @vport: vport from which to retrieve the stats 242 * @stats: location to store stats 243 * 244 * Retrieves transmit, receive, and error stats for the given device. 245 * 246 * Must be called with ovs_mutex or rcu_read_lock. 247 */ 248 void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats) 249 { 250 int i; 251 252 memset(stats, 0, sizeof(*stats)); 253 254 /* We potentially have 2 sources of stats that need to be combined: 255 * those we have collected (split into err_stats and percpu_stats) from 256 * set_stats() and device error stats from netdev->get_stats() (for 257 * errors that happen downstream and therefore aren't reported through 258 * our vport_record_error() function). 259 * Stats from first source are reported by ovs (OVS_VPORT_ATTR_STATS). 260 * netdev-stats can be directly read over netlink-ioctl. 261 */ 262 263 spin_lock_bh(&vport->stats_lock); 264 265 stats->rx_errors = vport->err_stats.rx_errors; 266 stats->tx_errors = vport->err_stats.tx_errors; 267 stats->tx_dropped = vport->err_stats.tx_dropped; 268 stats->rx_dropped = vport->err_stats.rx_dropped; 269 270 spin_unlock_bh(&vport->stats_lock); 271 272 for_each_possible_cpu(i) { 273 const struct pcpu_sw_netstats *percpu_stats; 274 struct pcpu_sw_netstats local_stats; 275 unsigned int start; 276 277 percpu_stats = per_cpu_ptr(vport->percpu_stats, i); 278 279 do { 280 start = u64_stats_fetch_begin_irq(&percpu_stats->syncp); 281 local_stats = *percpu_stats; 282 } while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start)); 283 284 stats->rx_bytes += local_stats.rx_bytes; 285 stats->rx_packets += local_stats.rx_packets; 286 stats->tx_bytes += local_stats.tx_bytes; 287 stats->tx_packets += local_stats.tx_packets; 288 } 289 } 290 291 /** 292 * ovs_vport_get_options - retrieve device options 293 * 294 * @vport: vport from which to retrieve the options. 295 * @skb: sk_buff where options should be appended. 296 * 297 * Retrieves the configuration of the given device, appending an 298 * %OVS_VPORT_ATTR_OPTIONS attribute that in turn contains nested 299 * vport-specific attributes to @skb. 300 * 301 * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room, or another 302 * negative error code if a real error occurred. If an error occurs, @skb is 303 * left unmodified. 304 * 305 * Must be called with ovs_mutex or rcu_read_lock. 306 */ 307 int ovs_vport_get_options(const struct vport *vport, struct sk_buff *skb) 308 { 309 struct nlattr *nla; 310 int err; 311 312 if (!vport->ops->get_options) 313 return 0; 314 315 nla = nla_nest_start(skb, OVS_VPORT_ATTR_OPTIONS); 316 if (!nla) 317 return -EMSGSIZE; 318 319 err = vport->ops->get_options(vport, skb); 320 if (err) { 321 nla_nest_cancel(skb, nla); 322 return err; 323 } 324 325 nla_nest_end(skb, nla); 326 return 0; 327 } 328 329 /** 330 * ovs_vport_receive - pass up received packet to the datapath for processing 331 * 332 * @vport: vport that received the packet 333 * @skb: skb that was received 334 * @tun_key: tunnel (if any) that carried packet 335 * 336 * Must be called with rcu_read_lock. The packet cannot be shared and 337 * skb->data should point to the Ethernet header. 338 */ 339 void ovs_vport_receive(struct vport *vport, struct sk_buff *skb, 340 struct ovs_key_ipv4_tunnel *tun_key) 341 { 342 struct pcpu_sw_netstats *stats; 343 344 stats = this_cpu_ptr(vport->percpu_stats); 345 u64_stats_update_begin(&stats->syncp); 346 stats->rx_packets++; 347 stats->rx_bytes += skb->len; 348 u64_stats_update_end(&stats->syncp); 349 350 OVS_CB(skb)->tun_key = tun_key; 351 ovs_dp_process_received_packet(vport, skb); 352 } 353 354 /** 355 * ovs_vport_send - send a packet on a device 356 * 357 * @vport: vport on which to send the packet 358 * @skb: skb to send 359 * 360 * Sends the given packet and returns the length of data sent. Either ovs 361 * lock or rcu_read_lock must be held. 362 */ 363 int ovs_vport_send(struct vport *vport, struct sk_buff *skb) 364 { 365 int sent = vport->ops->send(vport, skb); 366 367 if (likely(sent > 0)) { 368 struct pcpu_sw_netstats *stats; 369 370 stats = this_cpu_ptr(vport->percpu_stats); 371 372 u64_stats_update_begin(&stats->syncp); 373 stats->tx_packets++; 374 stats->tx_bytes += sent; 375 u64_stats_update_end(&stats->syncp); 376 } else if (sent < 0) { 377 ovs_vport_record_error(vport, VPORT_E_TX_ERROR); 378 kfree_skb(skb); 379 } else 380 ovs_vport_record_error(vport, VPORT_E_TX_DROPPED); 381 382 return sent; 383 } 384 385 /** 386 * ovs_vport_record_error - indicate device error to generic stats layer 387 * 388 * @vport: vport that encountered the error 389 * @err_type: one of enum vport_err_type types to indicate the error type 390 * 391 * If using the vport generic stats layer indicate that an error of the given 392 * type has occurred. 393 */ 394 static void ovs_vport_record_error(struct vport *vport, 395 enum vport_err_type err_type) 396 { 397 spin_lock(&vport->stats_lock); 398 399 switch (err_type) { 400 case VPORT_E_RX_DROPPED: 401 vport->err_stats.rx_dropped++; 402 break; 403 404 case VPORT_E_RX_ERROR: 405 vport->err_stats.rx_errors++; 406 break; 407 408 case VPORT_E_TX_DROPPED: 409 vport->err_stats.tx_dropped++; 410 break; 411 412 case VPORT_E_TX_ERROR: 413 vport->err_stats.tx_errors++; 414 break; 415 } 416 417 spin_unlock(&vport->stats_lock); 418 } 419 420 static void free_vport_rcu(struct rcu_head *rcu) 421 { 422 struct vport *vport = container_of(rcu, struct vport, rcu); 423 424 ovs_vport_free(vport); 425 } 426 427 void ovs_vport_deferred_free(struct vport *vport) 428 { 429 if (!vport) 430 return; 431 432 call_rcu(&vport->rcu, free_vport_rcu); 433 } 434