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