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, ovs_mutex 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 ovs 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 pcpu_tstats); 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). ovs_mutex 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 for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) { 173 if (vport_ops_list[i]->type == parms->type) { 174 struct hlist_head *bucket; 175 176 vport = vport_ops_list[i]->create(parms); 177 if (IS_ERR(vport)) { 178 err = PTR_ERR(vport); 179 goto out; 180 } 181 182 bucket = hash_bucket(ovs_dp_get_net(vport->dp), 183 vport->ops->get_name(vport)); 184 hlist_add_head_rcu(&vport->hash_node, bucket); 185 return vport; 186 } 187 } 188 189 err = -EAFNOSUPPORT; 190 191 out: 192 return ERR_PTR(err); 193 } 194 195 /** 196 * ovs_vport_set_options - modify existing vport device (for kernel callers) 197 * 198 * @vport: vport to modify. 199 * @port: New configuration. 200 * 201 * Modifies an existing device with the specified configuration (which is 202 * dependent on device type). ovs_mutex must be held. 203 */ 204 int ovs_vport_set_options(struct vport *vport, struct nlattr *options) 205 { 206 if (!vport->ops->set_options) 207 return -EOPNOTSUPP; 208 return vport->ops->set_options(vport, options); 209 } 210 211 /** 212 * ovs_vport_del - delete existing vport device 213 * 214 * @vport: vport to delete. 215 * 216 * Detaches @vport from its datapath and destroys it. It is possible to fail 217 * for reasons such as lack of memory. ovs_mutex must be held. 218 */ 219 void ovs_vport_del(struct vport *vport) 220 { 221 ASSERT_OVSL(); 222 223 hlist_del_rcu(&vport->hash_node); 224 225 vport->ops->destroy(vport); 226 } 227 228 /** 229 * ovs_vport_get_stats - retrieve device stats 230 * 231 * @vport: vport from which to retrieve the stats 232 * @stats: location to store stats 233 * 234 * Retrieves transmit, receive, and error stats for the given device. 235 * 236 * Must be called with ovs_mutex or rcu_read_lock. 237 */ 238 void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats) 239 { 240 int i; 241 242 memset(stats, 0, sizeof(*stats)); 243 244 /* We potentially have 2 sources of stats that need to be combined: 245 * those we have collected (split into err_stats and percpu_stats) from 246 * set_stats() and device error stats from netdev->get_stats() (for 247 * errors that happen downstream and therefore aren't reported through 248 * our vport_record_error() function). 249 * Stats from first source are reported by ovs (OVS_VPORT_ATTR_STATS). 250 * netdev-stats can be directly read over netlink-ioctl. 251 */ 252 253 spin_lock_bh(&vport->stats_lock); 254 255 stats->rx_errors = vport->err_stats.rx_errors; 256 stats->tx_errors = vport->err_stats.tx_errors; 257 stats->tx_dropped = vport->err_stats.tx_dropped; 258 stats->rx_dropped = vport->err_stats.rx_dropped; 259 260 spin_unlock_bh(&vport->stats_lock); 261 262 for_each_possible_cpu(i) { 263 const struct pcpu_tstats *percpu_stats; 264 struct pcpu_tstats local_stats; 265 unsigned int start; 266 267 percpu_stats = per_cpu_ptr(vport->percpu_stats, i); 268 269 do { 270 start = u64_stats_fetch_begin_bh(&percpu_stats->syncp); 271 local_stats = *percpu_stats; 272 } while (u64_stats_fetch_retry_bh(&percpu_stats->syncp, start)); 273 274 stats->rx_bytes += local_stats.rx_bytes; 275 stats->rx_packets += local_stats.rx_packets; 276 stats->tx_bytes += local_stats.tx_bytes; 277 stats->tx_packets += local_stats.tx_packets; 278 } 279 } 280 281 /** 282 * ovs_vport_get_options - retrieve device options 283 * 284 * @vport: vport from which to retrieve the options. 285 * @skb: sk_buff where options should be appended. 286 * 287 * Retrieves the configuration of the given device, appending an 288 * %OVS_VPORT_ATTR_OPTIONS attribute that in turn contains nested 289 * vport-specific attributes to @skb. 290 * 291 * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room, or another 292 * negative error code if a real error occurred. If an error occurs, @skb is 293 * left unmodified. 294 * 295 * Must be called with ovs_mutex or rcu_read_lock. 296 */ 297 int ovs_vport_get_options(const struct vport *vport, struct sk_buff *skb) 298 { 299 struct nlattr *nla; 300 int err; 301 302 if (!vport->ops->get_options) 303 return 0; 304 305 nla = nla_nest_start(skb, OVS_VPORT_ATTR_OPTIONS); 306 if (!nla) 307 return -EMSGSIZE; 308 309 err = vport->ops->get_options(vport, skb); 310 if (err) { 311 nla_nest_cancel(skb, nla); 312 return err; 313 } 314 315 nla_nest_end(skb, nla); 316 return 0; 317 } 318 319 /** 320 * ovs_vport_receive - pass up received packet to the datapath for processing 321 * 322 * @vport: vport that received the packet 323 * @skb: skb that was received 324 * 325 * Must be called with rcu_read_lock. The packet cannot be shared and 326 * skb->data should point to the Ethernet header. 327 */ 328 void ovs_vport_receive(struct vport *vport, struct sk_buff *skb) 329 { 330 struct pcpu_tstats *stats; 331 332 stats = this_cpu_ptr(vport->percpu_stats); 333 u64_stats_update_begin(&stats->syncp); 334 stats->rx_packets++; 335 stats->rx_bytes += skb->len; 336 u64_stats_update_end(&stats->syncp); 337 338 ovs_dp_process_received_packet(vport, skb); 339 } 340 341 /** 342 * ovs_vport_send - send a packet on a device 343 * 344 * @vport: vport on which to send the packet 345 * @skb: skb to send 346 * 347 * Sends the given packet and returns the length of data sent. Either ovs 348 * lock or rcu_read_lock must be held. 349 */ 350 int ovs_vport_send(struct vport *vport, struct sk_buff *skb) 351 { 352 int sent = vport->ops->send(vport, skb); 353 354 if (likely(sent)) { 355 struct pcpu_tstats *stats; 356 357 stats = this_cpu_ptr(vport->percpu_stats); 358 359 u64_stats_update_begin(&stats->syncp); 360 stats->tx_packets++; 361 stats->tx_bytes += sent; 362 u64_stats_update_end(&stats->syncp); 363 } 364 return sent; 365 } 366 367 /** 368 * ovs_vport_record_error - indicate device error to generic stats layer 369 * 370 * @vport: vport that encountered the error 371 * @err_type: one of enum vport_err_type types to indicate the error type 372 * 373 * If using the vport generic stats layer indicate that an error of the given 374 * type has occured. 375 */ 376 void ovs_vport_record_error(struct vport *vport, enum vport_err_type err_type) 377 { 378 spin_lock(&vport->stats_lock); 379 380 switch (err_type) { 381 case VPORT_E_RX_DROPPED: 382 vport->err_stats.rx_dropped++; 383 break; 384 385 case VPORT_E_RX_ERROR: 386 vport->err_stats.rx_errors++; 387 break; 388 389 case VPORT_E_TX_DROPPED: 390 vport->err_stats.tx_dropped++; 391 break; 392 393 case VPORT_E_TX_ERROR: 394 vport->err_stats.tx_errors++; 395 break; 396 } 397 398 spin_unlock(&vport->stats_lock); 399 } 400