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