1/* 2 * Copyright (c) 2007-2014 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 36static 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. */ 41static 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#ifdef CONFIG_OPENVSWITCH_GENEVE 52 &ovs_geneve_vport_ops, 53#endif 54}; 55 56/* Protected by RCU read lock for reading, ovs_mutex for writing. */ 57static struct hlist_head *dev_table; 58#define VPORT_HASH_BUCKETS 1024 59 60/** 61 * ovs_vport_init - initialize vport subsystem 62 * 63 * Called at module load time to initialize the vport subsystem. 64 */ 65int ovs_vport_init(void) 66{ 67 dev_table = kzalloc(VPORT_HASH_BUCKETS * sizeof(struct hlist_head), 68 GFP_KERNEL); 69 if (!dev_table) 70 return -ENOMEM; 71 72 return 0; 73} 74 75/** 76 * ovs_vport_exit - shutdown vport subsystem 77 * 78 * Called at module exit time to shutdown the vport subsystem. 79 */ 80void ovs_vport_exit(void) 81{ 82 kfree(dev_table); 83} 84 85static struct hlist_head *hash_bucket(struct net *net, const char *name) 86{ 87 unsigned int hash = jhash(name, strlen(name), (unsigned long) net); 88 return &dev_table[hash & (VPORT_HASH_BUCKETS - 1)]; 89} 90 91/** 92 * ovs_vport_locate - find a port that has already been created 93 * 94 * @name: name of port to find 95 * 96 * Must be called with ovs or RCU read lock. 97 */ 98struct vport *ovs_vport_locate(struct net *net, const char *name) 99{ 100 struct hlist_head *bucket = hash_bucket(net, name); 101 struct vport *vport; 102 103 hlist_for_each_entry_rcu(vport, bucket, hash_node) 104 if (!strcmp(name, vport->ops->get_name(vport)) && 105 net_eq(ovs_dp_get_net(vport->dp), net)) 106 return vport; 107 108 return NULL; 109} 110 111/** 112 * ovs_vport_alloc - allocate and initialize new vport 113 * 114 * @priv_size: Size of private data area to allocate. 115 * @ops: vport device ops 116 * 117 * Allocate and initialize a new vport defined by @ops. The vport will contain 118 * a private data area of size @priv_size that can be accessed using 119 * vport_priv(). vports that are no longer needed should be released with 120 * vport_free(). 121 */ 122struct vport *ovs_vport_alloc(int priv_size, const struct vport_ops *ops, 123 const struct vport_parms *parms) 124{ 125 struct vport *vport; 126 size_t alloc_size; 127 128 alloc_size = sizeof(struct vport); 129 if (priv_size) { 130 alloc_size = ALIGN(alloc_size, VPORT_ALIGN); 131 alloc_size += priv_size; 132 } 133 134 vport = kzalloc(alloc_size, GFP_KERNEL); 135 if (!vport) 136 return ERR_PTR(-ENOMEM); 137 138 vport->dp = parms->dp; 139 vport->port_no = parms->port_no; 140 vport->ops = ops; 141 INIT_HLIST_NODE(&vport->dp_hash_node); 142 143 if (ovs_vport_set_upcall_portids(vport, parms->upcall_portids)) { 144 kfree(vport); 145 return ERR_PTR(-EINVAL); 146 } 147 148 vport->percpu_stats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 149 if (!vport->percpu_stats) { 150 kfree(vport); 151 return ERR_PTR(-ENOMEM); 152 } 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 */ 167void ovs_vport_free(struct vport *vport) 168{ 169 /* vport is freed from RCU callback or error path, Therefore 170 * it is safe to use raw dereference. 171 */ 172 kfree(rcu_dereference_raw(vport->upcall_portids)); 173 free_percpu(vport->percpu_stats); 174 kfree(vport); 175} 176 177/** 178 * ovs_vport_add - add vport device (for kernel callers) 179 * 180 * @parms: Information about new vport. 181 * 182 * Creates a new vport with the specified configuration (which is dependent on 183 * device type). ovs_mutex must be held. 184 */ 185struct vport *ovs_vport_add(const struct vport_parms *parms) 186{ 187 struct vport *vport; 188 int err = 0; 189 int i; 190 191 for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) { 192 if (vport_ops_list[i]->type == parms->type) { 193 struct hlist_head *bucket; 194 195 vport = vport_ops_list[i]->create(parms); 196 if (IS_ERR(vport)) { 197 err = PTR_ERR(vport); 198 goto out; 199 } 200 201 bucket = hash_bucket(ovs_dp_get_net(vport->dp), 202 vport->ops->get_name(vport)); 203 hlist_add_head_rcu(&vport->hash_node, bucket); 204 return vport; 205 } 206 } 207 208 err = -EAFNOSUPPORT; 209 210out: 211 return ERR_PTR(err); 212} 213 214/** 215 * ovs_vport_set_options - modify existing vport device (for kernel callers) 216 * 217 * @vport: vport to modify. 218 * @options: New configuration. 219 * 220 * Modifies an existing device with the specified configuration (which is 221 * dependent on device type). ovs_mutex must be held. 222 */ 223int ovs_vport_set_options(struct vport *vport, struct nlattr *options) 224{ 225 if (!vport->ops->set_options) 226 return -EOPNOTSUPP; 227 return vport->ops->set_options(vport, options); 228} 229 230/** 231 * ovs_vport_del - delete existing vport device 232 * 233 * @vport: vport to delete. 234 * 235 * Detaches @vport from its datapath and destroys it. It is possible to fail 236 * for reasons such as lack of memory. ovs_mutex must be held. 237 */ 238void ovs_vport_del(struct vport *vport) 239{ 240 ASSERT_OVSL(); 241 242 hlist_del_rcu(&vport->hash_node); 243 244 vport->ops->destroy(vport); 245} 246 247/** 248 * ovs_vport_get_stats - retrieve device stats 249 * 250 * @vport: vport from which to retrieve the stats 251 * @stats: location to store stats 252 * 253 * Retrieves transmit, receive, and error stats for the given device. 254 * 255 * Must be called with ovs_mutex or rcu_read_lock. 256 */ 257void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats) 258{ 259 int i; 260 261 memset(stats, 0, sizeof(*stats)); 262 263 /* We potentially have 2 sources of stats that need to be combined: 264 * those we have collected (split into err_stats and percpu_stats) from 265 * set_stats() and device error stats from netdev->get_stats() (for 266 * errors that happen downstream and therefore aren't reported through 267 * our vport_record_error() function). 268 * Stats from first source are reported by ovs (OVS_VPORT_ATTR_STATS). 269 * netdev-stats can be directly read over netlink-ioctl. 270 */ 271 272 stats->rx_errors = atomic_long_read(&vport->err_stats.rx_errors); 273 stats->tx_errors = atomic_long_read(&vport->err_stats.tx_errors); 274 stats->tx_dropped = atomic_long_read(&vport->err_stats.tx_dropped); 275 stats->rx_dropped = atomic_long_read(&vport->err_stats.rx_dropped); 276 277 for_each_possible_cpu(i) { 278 const struct pcpu_sw_netstats *percpu_stats; 279 struct pcpu_sw_netstats 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_irq(&percpu_stats->syncp); 286 local_stats = *percpu_stats; 287 } while (u64_stats_fetch_retry_irq(&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 */ 312int 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_set_upcall_portids - set upcall portids of @vport. 336 * 337 * @vport: vport to modify. 338 * @ids: new configuration, an array of port ids. 339 * 340 * Sets the vport's upcall_portids to @ids. 341 * 342 * Returns 0 if successful, -EINVAL if @ids is zero length or cannot be parsed 343 * as an array of U32. 344 * 345 * Must be called with ovs_mutex. 346 */ 347int ovs_vport_set_upcall_portids(struct vport *vport, struct nlattr *ids) 348{ 349 struct vport_portids *old, *vport_portids; 350 351 if (!nla_len(ids) || nla_len(ids) % sizeof(u32)) 352 return -EINVAL; 353 354 old = ovsl_dereference(vport->upcall_portids); 355 356 vport_portids = kmalloc(sizeof(*vport_portids) + nla_len(ids), 357 GFP_KERNEL); 358 if (!vport_portids) 359 return -ENOMEM; 360 361 vport_portids->n_ids = nla_len(ids) / sizeof(u32); 362 vport_portids->rn_ids = reciprocal_value(vport_portids->n_ids); 363 nla_memcpy(vport_portids->ids, ids, nla_len(ids)); 364 365 rcu_assign_pointer(vport->upcall_portids, vport_portids); 366 367 if (old) 368 kfree_rcu(old, rcu); 369 return 0; 370} 371 372/** 373 * ovs_vport_get_upcall_portids - get the upcall_portids of @vport. 374 * 375 * @vport: vport from which to retrieve the portids. 376 * @skb: sk_buff where portids should be appended. 377 * 378 * Retrieves the configuration of the given vport, appending the 379 * %OVS_VPORT_ATTR_UPCALL_PID attribute which is the array of upcall 380 * portids to @skb. 381 * 382 * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room. 383 * If an error occurs, @skb is left unmodified. Must be called with 384 * ovs_mutex or rcu_read_lock. 385 */ 386int ovs_vport_get_upcall_portids(const struct vport *vport, 387 struct sk_buff *skb) 388{ 389 struct vport_portids *ids; 390 391 ids = rcu_dereference_ovsl(vport->upcall_portids); 392 393 if (vport->dp->user_features & OVS_DP_F_VPORT_PIDS) 394 return nla_put(skb, OVS_VPORT_ATTR_UPCALL_PID, 395 ids->n_ids * sizeof(u32), (void *)ids->ids); 396 else 397 return nla_put_u32(skb, OVS_VPORT_ATTR_UPCALL_PID, ids->ids[0]); 398} 399 400/** 401 * ovs_vport_find_upcall_portid - find the upcall portid to send upcall. 402 * 403 * @vport: vport from which the missed packet is received. 404 * @skb: skb that the missed packet was received. 405 * 406 * Uses the skb_get_hash() to select the upcall portid to send the 407 * upcall. 408 * 409 * Returns the portid of the target socket. Must be called with rcu_read_lock. 410 */ 411u32 ovs_vport_find_upcall_portid(const struct vport *vport, struct sk_buff *skb) 412{ 413 struct vport_portids *ids; 414 u32 ids_index; 415 u32 hash; 416 417 ids = rcu_dereference(vport->upcall_portids); 418 419 if (ids->n_ids == 1 && ids->ids[0] == 0) 420 return 0; 421 422 hash = skb_get_hash(skb); 423 ids_index = hash - ids->n_ids * reciprocal_divide(hash, ids->rn_ids); 424 return ids->ids[ids_index]; 425} 426 427/** 428 * ovs_vport_receive - pass up received packet to the datapath for processing 429 * 430 * @vport: vport that received the packet 431 * @skb: skb that was received 432 * @tun_key: tunnel (if any) that carried packet 433 * 434 * Must be called with rcu_read_lock. The packet cannot be shared and 435 * skb->data should point to the Ethernet header. 436 */ 437void ovs_vport_receive(struct vport *vport, struct sk_buff *skb, 438 struct ovs_tunnel_info *tun_info) 439{ 440 struct pcpu_sw_netstats *stats; 441 struct sw_flow_key key; 442 int error; 443 444 stats = this_cpu_ptr(vport->percpu_stats); 445 u64_stats_update_begin(&stats->syncp); 446 stats->rx_packets++; 447 stats->rx_bytes += skb->len; 448 u64_stats_update_end(&stats->syncp); 449 450 OVS_CB(skb)->input_vport = vport; 451 OVS_CB(skb)->egress_tun_info = NULL; 452 /* Extract flow from 'skb' into 'key'. */ 453 error = ovs_flow_key_extract(tun_info, skb, &key); 454 if (unlikely(error)) { 455 kfree_skb(skb); 456 return; 457 } 458 ovs_dp_process_packet(skb, &key); 459} 460 461/** 462 * ovs_vport_send - send a packet on a device 463 * 464 * @vport: vport on which to send the packet 465 * @skb: skb to send 466 * 467 * Sends the given packet and returns the length of data sent. Either ovs 468 * lock or rcu_read_lock must be held. 469 */ 470int ovs_vport_send(struct vport *vport, struct sk_buff *skb) 471{ 472 int sent = vport->ops->send(vport, skb); 473 474 if (likely(sent > 0)) { 475 struct pcpu_sw_netstats *stats; 476 477 stats = this_cpu_ptr(vport->percpu_stats); 478 479 u64_stats_update_begin(&stats->syncp); 480 stats->tx_packets++; 481 stats->tx_bytes += sent; 482 u64_stats_update_end(&stats->syncp); 483 } else if (sent < 0) { 484 ovs_vport_record_error(vport, VPORT_E_TX_ERROR); 485 kfree_skb(skb); 486 } else 487 ovs_vport_record_error(vport, VPORT_E_TX_DROPPED); 488 489 return sent; 490} 491 492/** 493 * ovs_vport_record_error - indicate device error to generic stats layer 494 * 495 * @vport: vport that encountered the error 496 * @err_type: one of enum vport_err_type types to indicate the error type 497 * 498 * If using the vport generic stats layer indicate that an error of the given 499 * type has occurred. 500 */ 501static void ovs_vport_record_error(struct vport *vport, 502 enum vport_err_type err_type) 503{ 504 switch (err_type) { 505 case VPORT_E_RX_DROPPED: 506 atomic_long_inc(&vport->err_stats.rx_dropped); 507 break; 508 509 case VPORT_E_RX_ERROR: 510 atomic_long_inc(&vport->err_stats.rx_errors); 511 break; 512 513 case VPORT_E_TX_DROPPED: 514 atomic_long_inc(&vport->err_stats.tx_dropped); 515 break; 516 517 case VPORT_E_TX_ERROR: 518 atomic_long_inc(&vport->err_stats.tx_errors); 519 break; 520 } 521 522} 523 524static void free_vport_rcu(struct rcu_head *rcu) 525{ 526 struct vport *vport = container_of(rcu, struct vport, rcu); 527 528 ovs_vport_free(vport); 529} 530 531void ovs_vport_deferred_free(struct vport *vport) 532{ 533 if (!vport) 534 return; 535 536 call_rcu(&vport->rcu, free_vport_rcu); 537} 538