1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Handling of a master device, switching frames via its switch fabric CPU port 4 * 5 * Copyright (c) 2017 Savoir-faire Linux Inc. 6 * Vivien Didelot <vivien.didelot@savoirfairelinux.com> 7 */ 8 9 #include "dsa_priv.h" 10 11 static int dsa_master_get_regs_len(struct net_device *dev) 12 { 13 struct dsa_port *cpu_dp = dev->dsa_ptr; 14 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; 15 struct dsa_switch *ds = cpu_dp->ds; 16 int port = cpu_dp->index; 17 int ret = 0; 18 int len; 19 20 if (ops->get_regs_len) { 21 len = ops->get_regs_len(dev); 22 if (len < 0) 23 return len; 24 ret += len; 25 } 26 27 ret += sizeof(struct ethtool_drvinfo); 28 ret += sizeof(struct ethtool_regs); 29 30 if (ds->ops->get_regs_len) { 31 len = ds->ops->get_regs_len(ds, port); 32 if (len < 0) 33 return len; 34 ret += len; 35 } 36 37 return ret; 38 } 39 40 static void dsa_master_get_regs(struct net_device *dev, 41 struct ethtool_regs *regs, void *data) 42 { 43 struct dsa_port *cpu_dp = dev->dsa_ptr; 44 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; 45 struct dsa_switch *ds = cpu_dp->ds; 46 struct ethtool_drvinfo *cpu_info; 47 struct ethtool_regs *cpu_regs; 48 int port = cpu_dp->index; 49 int len; 50 51 if (ops->get_regs_len && ops->get_regs) { 52 len = ops->get_regs_len(dev); 53 if (len < 0) 54 return; 55 regs->len = len; 56 ops->get_regs(dev, regs, data); 57 data += regs->len; 58 } 59 60 cpu_info = (struct ethtool_drvinfo *)data; 61 strlcpy(cpu_info->driver, "dsa", sizeof(cpu_info->driver)); 62 data += sizeof(*cpu_info); 63 cpu_regs = (struct ethtool_regs *)data; 64 data += sizeof(*cpu_regs); 65 66 if (ds->ops->get_regs_len && ds->ops->get_regs) { 67 len = ds->ops->get_regs_len(ds, port); 68 if (len < 0) 69 return; 70 cpu_regs->len = len; 71 ds->ops->get_regs(ds, port, cpu_regs, data); 72 } 73 } 74 75 static void dsa_master_get_ethtool_stats(struct net_device *dev, 76 struct ethtool_stats *stats, 77 uint64_t *data) 78 { 79 struct dsa_port *cpu_dp = dev->dsa_ptr; 80 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; 81 struct dsa_switch *ds = cpu_dp->ds; 82 int port = cpu_dp->index; 83 int count = 0; 84 85 if (ops->get_sset_count && ops->get_ethtool_stats) { 86 count = ops->get_sset_count(dev, ETH_SS_STATS); 87 ops->get_ethtool_stats(dev, stats, data); 88 } 89 90 if (ds->ops->get_ethtool_stats) 91 ds->ops->get_ethtool_stats(ds, port, data + count); 92 } 93 94 static void dsa_master_get_ethtool_phy_stats(struct net_device *dev, 95 struct ethtool_stats *stats, 96 uint64_t *data) 97 { 98 struct dsa_port *cpu_dp = dev->dsa_ptr; 99 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; 100 struct dsa_switch *ds = cpu_dp->ds; 101 int port = cpu_dp->index; 102 int count = 0; 103 104 if (dev->phydev && !ops->get_ethtool_phy_stats) { 105 count = phy_ethtool_get_sset_count(dev->phydev); 106 if (count >= 0) 107 phy_ethtool_get_stats(dev->phydev, stats, data); 108 } else if (ops->get_sset_count && ops->get_ethtool_phy_stats) { 109 count = ops->get_sset_count(dev, ETH_SS_PHY_STATS); 110 ops->get_ethtool_phy_stats(dev, stats, data); 111 } 112 113 if (count < 0) 114 count = 0; 115 116 if (ds->ops->get_ethtool_phy_stats) 117 ds->ops->get_ethtool_phy_stats(ds, port, data + count); 118 } 119 120 static int dsa_master_get_sset_count(struct net_device *dev, int sset) 121 { 122 struct dsa_port *cpu_dp = dev->dsa_ptr; 123 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; 124 struct dsa_switch *ds = cpu_dp->ds; 125 int count = 0; 126 127 if (sset == ETH_SS_PHY_STATS && dev->phydev && 128 !ops->get_ethtool_phy_stats) 129 count = phy_ethtool_get_sset_count(dev->phydev); 130 else if (ops->get_sset_count) 131 count = ops->get_sset_count(dev, sset); 132 133 if (count < 0) 134 count = 0; 135 136 if (ds->ops->get_sset_count) 137 count += ds->ops->get_sset_count(ds, cpu_dp->index, sset); 138 139 return count; 140 } 141 142 static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset, 143 uint8_t *data) 144 { 145 struct dsa_port *cpu_dp = dev->dsa_ptr; 146 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; 147 struct dsa_switch *ds = cpu_dp->ds; 148 int port = cpu_dp->index; 149 int len = ETH_GSTRING_LEN; 150 int mcount = 0, count, i; 151 uint8_t pfx[4]; 152 uint8_t *ndata; 153 154 snprintf(pfx, sizeof(pfx), "p%.2d", port); 155 /* We do not want to be NULL-terminated, since this is a prefix */ 156 pfx[sizeof(pfx) - 1] = '_'; 157 158 if (stringset == ETH_SS_PHY_STATS && dev->phydev && 159 !ops->get_ethtool_phy_stats) { 160 mcount = phy_ethtool_get_sset_count(dev->phydev); 161 if (mcount < 0) 162 mcount = 0; 163 else 164 phy_ethtool_get_strings(dev->phydev, data); 165 } else if (ops->get_sset_count && ops->get_strings) { 166 mcount = ops->get_sset_count(dev, stringset); 167 if (mcount < 0) 168 mcount = 0; 169 ops->get_strings(dev, stringset, data); 170 } 171 172 if (ds->ops->get_strings) { 173 ndata = data + mcount * len; 174 /* This function copies ETH_GSTRINGS_LEN bytes, we will mangle 175 * the output after to prepend our CPU port prefix we 176 * constructed earlier 177 */ 178 ds->ops->get_strings(ds, port, stringset, ndata); 179 count = ds->ops->get_sset_count(ds, port, stringset); 180 if (count < 0) 181 return; 182 for (i = 0; i < count; i++) { 183 memmove(ndata + (i * len + sizeof(pfx)), 184 ndata + i * len, len - sizeof(pfx)); 185 memcpy(ndata + i * len, pfx, sizeof(pfx)); 186 } 187 } 188 } 189 190 static int dsa_master_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 191 { 192 struct dsa_port *cpu_dp = dev->dsa_ptr; 193 struct dsa_switch *ds = cpu_dp->ds; 194 struct dsa_switch_tree *dst; 195 int err = -EOPNOTSUPP; 196 struct dsa_port *dp; 197 198 dst = ds->dst; 199 200 switch (cmd) { 201 case SIOCGHWTSTAMP: 202 case SIOCSHWTSTAMP: 203 /* Deny PTP operations on master if there is at least one 204 * switch in the tree that is PTP capable. 205 */ 206 list_for_each_entry(dp, &dst->ports, list) 207 if (dp->ds->ops->port_hwtstamp_get || 208 dp->ds->ops->port_hwtstamp_set) 209 return -EBUSY; 210 break; 211 } 212 213 if (dev->netdev_ops->ndo_eth_ioctl) 214 err = dev->netdev_ops->ndo_eth_ioctl(dev, ifr, cmd); 215 216 return err; 217 } 218 219 static const struct dsa_netdevice_ops dsa_netdev_ops = { 220 .ndo_eth_ioctl = dsa_master_ioctl, 221 }; 222 223 static int dsa_master_ethtool_setup(struct net_device *dev) 224 { 225 struct dsa_port *cpu_dp = dev->dsa_ptr; 226 struct dsa_switch *ds = cpu_dp->ds; 227 struct ethtool_ops *ops; 228 229 ops = devm_kzalloc(ds->dev, sizeof(*ops), GFP_KERNEL); 230 if (!ops) 231 return -ENOMEM; 232 233 cpu_dp->orig_ethtool_ops = dev->ethtool_ops; 234 if (cpu_dp->orig_ethtool_ops) 235 memcpy(ops, cpu_dp->orig_ethtool_ops, sizeof(*ops)); 236 237 ops->get_regs_len = dsa_master_get_regs_len; 238 ops->get_regs = dsa_master_get_regs; 239 ops->get_sset_count = dsa_master_get_sset_count; 240 ops->get_ethtool_stats = dsa_master_get_ethtool_stats; 241 ops->get_strings = dsa_master_get_strings; 242 ops->get_ethtool_phy_stats = dsa_master_get_ethtool_phy_stats; 243 244 dev->ethtool_ops = ops; 245 246 return 0; 247 } 248 249 static void dsa_master_ethtool_teardown(struct net_device *dev) 250 { 251 struct dsa_port *cpu_dp = dev->dsa_ptr; 252 253 dev->ethtool_ops = cpu_dp->orig_ethtool_ops; 254 cpu_dp->orig_ethtool_ops = NULL; 255 } 256 257 static void dsa_netdev_ops_set(struct net_device *dev, 258 const struct dsa_netdevice_ops *ops) 259 { 260 dev->dsa_ptr->netdev_ops = ops; 261 } 262 263 /* Keep the master always promiscuous if the tagging protocol requires that 264 * (garbles MAC DA) or if it doesn't support unicast filtering, case in which 265 * it would revert to promiscuous mode as soon as we call dev_uc_add() on it 266 * anyway. 267 */ 268 static void dsa_master_set_promiscuity(struct net_device *dev, int inc) 269 { 270 const struct dsa_device_ops *ops = dev->dsa_ptr->tag_ops; 271 272 if ((dev->priv_flags & IFF_UNICAST_FLT) && !ops->promisc_on_master) 273 return; 274 275 ASSERT_RTNL(); 276 277 dev_set_promiscuity(dev, inc); 278 } 279 280 static ssize_t tagging_show(struct device *d, struct device_attribute *attr, 281 char *buf) 282 { 283 struct net_device *dev = to_net_dev(d); 284 struct dsa_port *cpu_dp = dev->dsa_ptr; 285 286 return sprintf(buf, "%s\n", 287 dsa_tag_protocol_to_str(cpu_dp->tag_ops)); 288 } 289 290 static ssize_t tagging_store(struct device *d, struct device_attribute *attr, 291 const char *buf, size_t count) 292 { 293 const struct dsa_device_ops *new_tag_ops, *old_tag_ops; 294 struct net_device *dev = to_net_dev(d); 295 struct dsa_port *cpu_dp = dev->dsa_ptr; 296 int err; 297 298 old_tag_ops = cpu_dp->tag_ops; 299 new_tag_ops = dsa_find_tagger_by_name(buf); 300 /* Bad tagger name, or module is not loaded? */ 301 if (IS_ERR(new_tag_ops)) 302 return PTR_ERR(new_tag_ops); 303 304 if (new_tag_ops == old_tag_ops) 305 /* Drop the temporarily held duplicate reference, since 306 * the DSA switch tree uses this tagger. 307 */ 308 goto out; 309 310 err = dsa_tree_change_tag_proto(cpu_dp->ds->dst, dev, new_tag_ops, 311 old_tag_ops); 312 if (err) { 313 /* On failure the old tagger is restored, so we don't need the 314 * driver for the new one. 315 */ 316 dsa_tag_driver_put(new_tag_ops); 317 return err; 318 } 319 320 /* On success we no longer need the module for the old tagging protocol 321 */ 322 out: 323 dsa_tag_driver_put(old_tag_ops); 324 return count; 325 } 326 static DEVICE_ATTR_RW(tagging); 327 328 static struct attribute *dsa_slave_attrs[] = { 329 &dev_attr_tagging.attr, 330 NULL 331 }; 332 333 static const struct attribute_group dsa_group = { 334 .name = "dsa", 335 .attrs = dsa_slave_attrs, 336 }; 337 338 static void dsa_master_reset_mtu(struct net_device *dev) 339 { 340 int err; 341 342 err = dev_set_mtu(dev, ETH_DATA_LEN); 343 if (err) 344 netdev_dbg(dev, 345 "Unable to reset MTU to exclude DSA overheads\n"); 346 } 347 348 int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp) 349 { 350 const struct dsa_device_ops *tag_ops = cpu_dp->tag_ops; 351 struct dsa_switch *ds = cpu_dp->ds; 352 struct device_link *consumer_link; 353 int mtu, ret; 354 355 mtu = ETH_DATA_LEN + dsa_tag_protocol_overhead(tag_ops); 356 357 /* The DSA master must use SET_NETDEV_DEV for this to work. */ 358 consumer_link = device_link_add(ds->dev, dev->dev.parent, 359 DL_FLAG_AUTOREMOVE_CONSUMER); 360 if (!consumer_link) 361 netdev_err(dev, 362 "Failed to create a device link to DSA switch %s\n", 363 dev_name(ds->dev)); 364 365 /* The switch driver may not implement ->port_change_mtu(), case in 366 * which dsa_slave_change_mtu() will not update the master MTU either, 367 * so we need to do that here. 368 */ 369 ret = dev_set_mtu(dev, mtu); 370 if (ret) 371 netdev_warn(dev, "error %d setting MTU to %d to include DSA overhead\n", 372 ret, mtu); 373 374 /* If we use a tagging format that doesn't have an ethertype 375 * field, make sure that all packets from this point on get 376 * sent to the tag format's receive function. 377 */ 378 wmb(); 379 380 dev->dsa_ptr = cpu_dp; 381 382 dsa_master_set_promiscuity(dev, 1); 383 384 ret = dsa_master_ethtool_setup(dev); 385 if (ret) 386 goto out_err_reset_promisc; 387 388 dsa_netdev_ops_set(dev, &dsa_netdev_ops); 389 390 ret = sysfs_create_group(&dev->dev.kobj, &dsa_group); 391 if (ret) 392 goto out_err_ndo_teardown; 393 394 return ret; 395 396 out_err_ndo_teardown: 397 dsa_netdev_ops_set(dev, NULL); 398 dsa_master_ethtool_teardown(dev); 399 out_err_reset_promisc: 400 dsa_master_set_promiscuity(dev, -1); 401 return ret; 402 } 403 404 void dsa_master_teardown(struct net_device *dev) 405 { 406 sysfs_remove_group(&dev->dev.kobj, &dsa_group); 407 dsa_netdev_ops_set(dev, NULL); 408 dsa_master_ethtool_teardown(dev); 409 dsa_master_reset_mtu(dev); 410 dsa_master_set_promiscuity(dev, -1); 411 412 dev->dsa_ptr = NULL; 413 414 /* If we used a tagging format that doesn't have an ethertype 415 * field, make sure that all packets from this point get sent 416 * without the tag and go through the regular receive path. 417 */ 418 wmb(); 419 } 420