1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (C) 2017 Netronome Systems, Inc. 3 * Copyright (C) 2019 Mellanox Technologies. All rights reserved 4 */ 5 6 #include <linux/device.h> 7 #include <linux/idr.h> 8 #include <linux/kernel.h> 9 #include <linux/list.h> 10 #include <linux/mutex.h> 11 #include <linux/rtnetlink.h> 12 #include <linux/slab.h> 13 #include <linux/sysfs.h> 14 15 #include "netdevsim.h" 16 17 static DEFINE_IDA(nsim_bus_dev_ids); 18 static LIST_HEAD(nsim_bus_dev_list); 19 static DEFINE_MUTEX(nsim_bus_dev_list_lock); 20 static bool nsim_bus_enable; 21 22 static struct nsim_bus_dev *to_nsim_bus_dev(struct device *dev) 23 { 24 return container_of(dev, struct nsim_bus_dev, dev); 25 } 26 27 static int nsim_bus_dev_vfs_enable(struct nsim_bus_dev *nsim_bus_dev, 28 unsigned int num_vfs) 29 { 30 nsim_bus_dev->vfconfigs = kcalloc(num_vfs, 31 sizeof(struct nsim_vf_config), 32 GFP_KERNEL | __GFP_NOWARN); 33 if (!nsim_bus_dev->vfconfigs) 34 return -ENOMEM; 35 nsim_bus_dev->num_vfs = num_vfs; 36 37 return 0; 38 } 39 40 static void nsim_bus_dev_vfs_disable(struct nsim_bus_dev *nsim_bus_dev) 41 { 42 kfree(nsim_bus_dev->vfconfigs); 43 nsim_bus_dev->vfconfigs = NULL; 44 nsim_bus_dev->num_vfs = 0; 45 } 46 47 static ssize_t 48 nsim_bus_dev_numvfs_store(struct device *dev, struct device_attribute *attr, 49 const char *buf, size_t count) 50 { 51 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); 52 unsigned int num_vfs; 53 int ret; 54 55 ret = kstrtouint(buf, 0, &num_vfs); 56 if (ret) 57 return ret; 58 59 rtnl_lock(); 60 if (nsim_bus_dev->num_vfs == num_vfs) 61 goto exit_good; 62 if (nsim_bus_dev->num_vfs && num_vfs) { 63 ret = -EBUSY; 64 goto exit_unlock; 65 } 66 67 if (num_vfs) { 68 ret = nsim_bus_dev_vfs_enable(nsim_bus_dev, num_vfs); 69 if (ret) 70 goto exit_unlock; 71 } else { 72 nsim_bus_dev_vfs_disable(nsim_bus_dev); 73 } 74 exit_good: 75 ret = count; 76 exit_unlock: 77 rtnl_unlock(); 78 79 return ret; 80 } 81 82 static ssize_t 83 nsim_bus_dev_numvfs_show(struct device *dev, 84 struct device_attribute *attr, char *buf) 85 { 86 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); 87 88 return sprintf(buf, "%u\n", nsim_bus_dev->num_vfs); 89 } 90 91 static struct device_attribute nsim_bus_dev_numvfs_attr = 92 __ATTR(sriov_numvfs, 0664, nsim_bus_dev_numvfs_show, 93 nsim_bus_dev_numvfs_store); 94 95 static ssize_t 96 new_port_store(struct device *dev, struct device_attribute *attr, 97 const char *buf, size_t count) 98 { 99 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); 100 struct nsim_dev *nsim_dev = dev_get_drvdata(dev); 101 struct devlink *devlink; 102 unsigned int port_index; 103 int ret; 104 105 /* Prevent to use nsim_bus_dev before initialization. */ 106 if (!smp_load_acquire(&nsim_bus_dev->init)) 107 return -EBUSY; 108 ret = kstrtouint(buf, 0, &port_index); 109 if (ret) 110 return ret; 111 112 devlink = priv_to_devlink(nsim_dev); 113 114 mutex_lock(&nsim_bus_dev->nsim_bus_reload_lock); 115 devlink_reload_disable(devlink); 116 ret = nsim_dev_port_add(nsim_bus_dev, port_index); 117 devlink_reload_enable(devlink); 118 mutex_unlock(&nsim_bus_dev->nsim_bus_reload_lock); 119 return ret ? ret : count; 120 } 121 122 static struct device_attribute nsim_bus_dev_new_port_attr = __ATTR_WO(new_port); 123 124 static ssize_t 125 del_port_store(struct device *dev, struct device_attribute *attr, 126 const char *buf, size_t count) 127 { 128 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); 129 struct nsim_dev *nsim_dev = dev_get_drvdata(dev); 130 struct devlink *devlink; 131 unsigned int port_index; 132 int ret; 133 134 /* Prevent to use nsim_bus_dev before initialization. */ 135 if (!smp_load_acquire(&nsim_bus_dev->init)) 136 return -EBUSY; 137 ret = kstrtouint(buf, 0, &port_index); 138 if (ret) 139 return ret; 140 141 devlink = priv_to_devlink(nsim_dev); 142 143 mutex_lock(&nsim_bus_dev->nsim_bus_reload_lock); 144 devlink_reload_disable(devlink); 145 ret = nsim_dev_port_del(nsim_bus_dev, port_index); 146 devlink_reload_enable(devlink); 147 mutex_unlock(&nsim_bus_dev->nsim_bus_reload_lock); 148 return ret ? ret : count; 149 } 150 151 static struct device_attribute nsim_bus_dev_del_port_attr = __ATTR_WO(del_port); 152 153 static struct attribute *nsim_bus_dev_attrs[] = { 154 &nsim_bus_dev_numvfs_attr.attr, 155 &nsim_bus_dev_new_port_attr.attr, 156 &nsim_bus_dev_del_port_attr.attr, 157 NULL, 158 }; 159 160 static const struct attribute_group nsim_bus_dev_attr_group = { 161 .attrs = nsim_bus_dev_attrs, 162 }; 163 164 static const struct attribute_group *nsim_bus_dev_attr_groups[] = { 165 &nsim_bus_dev_attr_group, 166 NULL, 167 }; 168 169 static void nsim_bus_dev_release(struct device *dev) 170 { 171 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); 172 173 nsim_bus_dev_vfs_disable(nsim_bus_dev); 174 } 175 176 static struct device_type nsim_bus_dev_type = { 177 .groups = nsim_bus_dev_attr_groups, 178 .release = nsim_bus_dev_release, 179 }; 180 181 static struct nsim_bus_dev * 182 nsim_bus_dev_new(unsigned int id, unsigned int port_count); 183 184 static ssize_t 185 new_device_store(struct bus_type *bus, const char *buf, size_t count) 186 { 187 struct nsim_bus_dev *nsim_bus_dev; 188 unsigned int port_count; 189 unsigned int id; 190 int err; 191 192 err = sscanf(buf, "%u %u", &id, &port_count); 193 switch (err) { 194 case 1: 195 port_count = 1; 196 /* fall through */ 197 case 2: 198 if (id > INT_MAX) { 199 pr_err("Value of \"id\" is too big.\n"); 200 return -EINVAL; 201 } 202 break; 203 default: 204 pr_err("Format for adding new device is \"id port_count\" (uint uint).\n"); 205 return -EINVAL; 206 } 207 208 mutex_lock(&nsim_bus_dev_list_lock); 209 /* Prevent to use resource before initialization. */ 210 if (!smp_load_acquire(&nsim_bus_enable)) { 211 err = -EBUSY; 212 goto err; 213 } 214 215 nsim_bus_dev = nsim_bus_dev_new(id, port_count); 216 if (IS_ERR(nsim_bus_dev)) { 217 err = PTR_ERR(nsim_bus_dev); 218 goto err; 219 } 220 221 /* Allow using nsim_bus_dev */ 222 smp_store_release(&nsim_bus_dev->init, true); 223 224 list_add_tail(&nsim_bus_dev->list, &nsim_bus_dev_list); 225 mutex_unlock(&nsim_bus_dev_list_lock); 226 227 return count; 228 err: 229 mutex_unlock(&nsim_bus_dev_list_lock); 230 return err; 231 } 232 static BUS_ATTR_WO(new_device); 233 234 static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev); 235 236 static ssize_t 237 del_device_store(struct bus_type *bus, const char *buf, size_t count) 238 { 239 struct nsim_bus_dev *nsim_bus_dev, *tmp; 240 unsigned int id; 241 int err; 242 243 err = sscanf(buf, "%u", &id); 244 switch (err) { 245 case 1: 246 if (id > INT_MAX) { 247 pr_err("Value of \"id\" is too big.\n"); 248 return -EINVAL; 249 } 250 break; 251 default: 252 pr_err("Format for deleting device is \"id\" (uint).\n"); 253 return -EINVAL; 254 } 255 256 err = -ENOENT; 257 mutex_lock(&nsim_bus_dev_list_lock); 258 /* Prevent to use resource before initialization. */ 259 if (!smp_load_acquire(&nsim_bus_enable)) { 260 mutex_unlock(&nsim_bus_dev_list_lock); 261 return -EBUSY; 262 } 263 list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) { 264 if (nsim_bus_dev->dev.id != id) 265 continue; 266 list_del(&nsim_bus_dev->list); 267 nsim_bus_dev_del(nsim_bus_dev); 268 err = 0; 269 break; 270 } 271 mutex_unlock(&nsim_bus_dev_list_lock); 272 return !err ? count : err; 273 } 274 static BUS_ATTR_WO(del_device); 275 276 static struct attribute *nsim_bus_attrs[] = { 277 &bus_attr_new_device.attr, 278 &bus_attr_del_device.attr, 279 NULL 280 }; 281 ATTRIBUTE_GROUPS(nsim_bus); 282 283 static int nsim_bus_probe(struct device *dev) 284 { 285 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); 286 287 return nsim_dev_probe(nsim_bus_dev); 288 } 289 290 static int nsim_bus_remove(struct device *dev) 291 { 292 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); 293 294 nsim_dev_remove(nsim_bus_dev); 295 return 0; 296 } 297 298 static int nsim_num_vf(struct device *dev) 299 { 300 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); 301 302 return nsim_bus_dev->num_vfs; 303 } 304 305 static struct bus_type nsim_bus = { 306 .name = DRV_NAME, 307 .dev_name = DRV_NAME, 308 .bus_groups = nsim_bus_groups, 309 .probe = nsim_bus_probe, 310 .remove = nsim_bus_remove, 311 .num_vf = nsim_num_vf, 312 }; 313 314 static struct nsim_bus_dev * 315 nsim_bus_dev_new(unsigned int id, unsigned int port_count) 316 { 317 struct nsim_bus_dev *nsim_bus_dev; 318 int err; 319 320 nsim_bus_dev = kzalloc(sizeof(*nsim_bus_dev), GFP_KERNEL); 321 if (!nsim_bus_dev) 322 return ERR_PTR(-ENOMEM); 323 324 err = ida_alloc_range(&nsim_bus_dev_ids, id, id, GFP_KERNEL); 325 if (err < 0) 326 goto err_nsim_bus_dev_free; 327 nsim_bus_dev->dev.id = err; 328 nsim_bus_dev->dev.bus = &nsim_bus; 329 nsim_bus_dev->dev.type = &nsim_bus_dev_type; 330 nsim_bus_dev->port_count = port_count; 331 nsim_bus_dev->initial_net = current->nsproxy->net_ns; 332 mutex_init(&nsim_bus_dev->nsim_bus_reload_lock); 333 /* Disallow using nsim_bus_dev */ 334 smp_store_release(&nsim_bus_dev->init, false); 335 336 err = device_register(&nsim_bus_dev->dev); 337 if (err) 338 goto err_nsim_bus_dev_id_free; 339 return nsim_bus_dev; 340 341 err_nsim_bus_dev_id_free: 342 ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id); 343 err_nsim_bus_dev_free: 344 kfree(nsim_bus_dev); 345 return ERR_PTR(err); 346 } 347 348 static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev) 349 { 350 /* Disallow using nsim_bus_dev */ 351 smp_store_release(&nsim_bus_dev->init, false); 352 device_unregister(&nsim_bus_dev->dev); 353 ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id); 354 kfree(nsim_bus_dev); 355 } 356 357 static struct device_driver nsim_driver = { 358 .name = DRV_NAME, 359 .bus = &nsim_bus, 360 .owner = THIS_MODULE, 361 }; 362 363 int nsim_bus_init(void) 364 { 365 int err; 366 367 err = bus_register(&nsim_bus); 368 if (err) 369 return err; 370 err = driver_register(&nsim_driver); 371 if (err) 372 goto err_bus_unregister; 373 /* Allow using resources */ 374 smp_store_release(&nsim_bus_enable, true); 375 return 0; 376 377 err_bus_unregister: 378 bus_unregister(&nsim_bus); 379 return err; 380 } 381 382 void nsim_bus_exit(void) 383 { 384 struct nsim_bus_dev *nsim_bus_dev, *tmp; 385 386 /* Disallow using resources */ 387 smp_store_release(&nsim_bus_enable, false); 388 389 mutex_lock(&nsim_bus_dev_list_lock); 390 list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) { 391 list_del(&nsim_bus_dev->list); 392 nsim_bus_dev_del(nsim_bus_dev); 393 } 394 mutex_unlock(&nsim_bus_dev_list_lock); 395 396 driver_unregister(&nsim_driver); 397 bus_unregister(&nsim_bus); 398 } 399