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 90 hlist_for_each_entry_rcu(vport, bucket, hash_node) 91 if (!strcmp(name, vport->ops->get_name(vport)) && 92 net_eq(ovs_dp_get_net(vport->dp), net)) 93 return vport; 94 95 return NULL; 96 } 97 98 /** 99 * ovs_vport_alloc - allocate and initialize new vport 100 * 101 * @priv_size: Size of private data area to allocate. 102 * @ops: vport device ops 103 * 104 * Allocate and initialize a new vport defined by @ops. The vport will contain 105 * a private data area of size @priv_size that can be accessed using 106 * vport_priv(). vports that are no longer needed should be released with 107 * vport_free(). 108 */ 109 struct vport *ovs_vport_alloc(int priv_size, const struct vport_ops *ops, 110 const struct vport_parms *parms) 111 { 112 struct vport *vport; 113 size_t alloc_size; 114 115 alloc_size = sizeof(struct vport); 116 if (priv_size) { 117 alloc_size = ALIGN(alloc_size, VPORT_ALIGN); 118 alloc_size += priv_size; 119 } 120 121 vport = kzalloc(alloc_size, GFP_KERNEL); 122 if (!vport) 123 return ERR_PTR(-ENOMEM); 124 125 vport->dp = parms->dp; 126 vport->port_no = parms->port_no; 127 vport->upcall_portid = parms->upcall_portid; 128 vport->ops = ops; 129 INIT_HLIST_NODE(&vport->dp_hash_node); 130 131 vport->percpu_stats = alloc_percpu(struct vport_percpu_stats); 132 if (!vport->percpu_stats) { 133 kfree(vport); 134 return ERR_PTR(-ENOMEM); 135 } 136 137 spin_lock_init(&vport->stats_lock); 138 139 return vport; 140 } 141 142 /** 143 * ovs_vport_free - uninitialize and free vport 144 * 145 * @vport: vport to free 146 * 147 * Frees a vport allocated with vport_alloc() when it is no longer needed. 148 * 149 * The caller must ensure that an RCU grace period has passed since the last 150 * time @vport was in a datapath. 151 */ 152 void ovs_vport_free(struct vport *vport) 153 { 154 free_percpu(vport->percpu_stats); 155 kfree(vport); 156 } 157 158 /** 159 * ovs_vport_add - add vport device (for kernel callers) 160 * 161 * @parms: Information about new vport. 162 * 163 * Creates a new vport with the specified configuration (which is dependent on 164 * device type). RTNL lock must be held. 165 */ 166 struct vport *ovs_vport_add(const struct vport_parms *parms) 167 { 168 struct vport *vport; 169 int err = 0; 170 int i; 171 172 ASSERT_RTNL(); 173 174 for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) { 175 if (vport_ops_list[i]->type == parms->type) { 176 struct hlist_head *bucket; 177 178 vport = vport_ops_list[i]->create(parms); 179 if (IS_ERR(vport)) { 180 err = PTR_ERR(vport); 181 goto out; 182 } 183 184 bucket = hash_bucket(ovs_dp_get_net(vport->dp), 185 vport->ops->get_name(vport)); 186 hlist_add_head_rcu(&vport->hash_node, bucket); 187 return vport; 188 } 189 } 190 191 err = -EAFNOSUPPORT; 192 193 out: 194 return ERR_PTR(err); 195 } 196 197 /** 198 * ovs_vport_set_options - modify existing vport device (for kernel callers) 199 * 200 * @vport: vport to modify. 201 * @port: New configuration. 202 * 203 * Modifies an existing device with the specified configuration (which is 204 * dependent on device type). RTNL lock must be held. 205 */ 206 int ovs_vport_set_options(struct vport *vport, struct nlattr *options) 207 { 208 ASSERT_RTNL(); 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. RTNL lock must be held. 222 */ 223 void ovs_vport_del(struct vport *vport) 224 { 225 ASSERT_RTNL(); 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 RTNL lock 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 vport_percpu_stats *percpu_stats; 268 struct vport_percpu_stats 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->sync); 275 local_stats = *percpu_stats; 276 } while (u64_stats_fetch_retry_bh(&percpu_stats->sync, 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 RTNL lock or rcu_read_lock. 300 */ 301 int ovs_vport_get_options(const struct vport *vport, struct sk_buff *skb) 302 { 303 struct nlattr *nla; 304 305 nla = nla_nest_start(skb, OVS_VPORT_ATTR_OPTIONS); 306 if (!nla) 307 return -EMSGSIZE; 308 309 if (vport->ops->get_options) { 310 int err = vport->ops->get_options(vport, skb); 311 if (err) { 312 nla_nest_cancel(skb, nla); 313 return err; 314 } 315 } 316 317 nla_nest_end(skb, nla); 318 return 0; 319 } 320 321 /** 322 * ovs_vport_receive - pass up received packet to the datapath for processing 323 * 324 * @vport: vport that received the packet 325 * @skb: skb that was received 326 * 327 * Must be called with rcu_read_lock. The packet cannot be shared and 328 * skb->data should point to the Ethernet header. The caller must have already 329 * called compute_ip_summed() to initialize the checksumming fields. 330 */ 331 void ovs_vport_receive(struct vport *vport, struct sk_buff *skb) 332 { 333 struct vport_percpu_stats *stats; 334 335 stats = this_cpu_ptr(vport->percpu_stats); 336 u64_stats_update_begin(&stats->sync); 337 stats->rx_packets++; 338 stats->rx_bytes += skb->len; 339 u64_stats_update_end(&stats->sync); 340 341 ovs_dp_process_received_packet(vport, skb); 342 } 343 344 /** 345 * ovs_vport_send - send a packet on a device 346 * 347 * @vport: vport on which to send the packet 348 * @skb: skb to send 349 * 350 * Sends the given packet and returns the length of data sent. Either RTNL 351 * lock or rcu_read_lock must be held. 352 */ 353 int ovs_vport_send(struct vport *vport, struct sk_buff *skb) 354 { 355 int sent = vport->ops->send(vport, skb); 356 357 if (likely(sent)) { 358 struct vport_percpu_stats *stats; 359 360 stats = this_cpu_ptr(vport->percpu_stats); 361 362 u64_stats_update_begin(&stats->sync); 363 stats->tx_packets++; 364 stats->tx_bytes += sent; 365 u64_stats_update_end(&stats->sync); 366 } 367 return sent; 368 } 369 370 /** 371 * ovs_vport_record_error - indicate device error to generic stats layer 372 * 373 * @vport: vport that encountered the error 374 * @err_type: one of enum vport_err_type types to indicate the error type 375 * 376 * If using the vport generic stats layer indicate that an error of the given 377 * type has occured. 378 */ 379 void ovs_vport_record_error(struct vport *vport, enum vport_err_type err_type) 380 { 381 spin_lock(&vport->stats_lock); 382 383 switch (err_type) { 384 case VPORT_E_RX_DROPPED: 385 vport->err_stats.rx_dropped++; 386 break; 387 388 case VPORT_E_RX_ERROR: 389 vport->err_stats.rx_errors++; 390 break; 391 392 case VPORT_E_TX_DROPPED: 393 vport->err_stats.tx_dropped++; 394 break; 395 396 case VPORT_E_TX_ERROR: 397 vport->err_stats.tx_errors++; 398 break; 399 } 400 401 spin_unlock(&vport->stats_lock); 402 } 403