kernel/linux/kni/kni_misc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright(c) 2010-2014 Intel Corporation.
   4  */
   5
   6 #include <linux/version.h>
   7 #include <linux/module.h>
   8 #include <linux/miscdevice.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/etherdevice.h>
  11 #include <linux/pci.h>
  12 #include <linux/kthread.h>
  13 #include <linux/rwsem.h>
  14 #include <linux/mutex.h>
  15 #include <linux/nsproxy.h>
  16 #include <net/net_namespace.h>
  17 #include <net/netns/generic.h>
  18
  19 #include <rte_kni_common.h>
  20
  21 #include "compat.h"
  22 #include "kni_dev.h"
  23
  24 MODULE_VERSION(KNI_VERSION);
  25 MODULE_LICENSE("Dual BSD/GPL");
  26 MODULE_AUTHOR("Intel Corporation");
  27 MODULE_DESCRIPTION("Kernel Module for managing kni devices");
  28
  29 #define KNI_RX_LOOP_NUM 1000
  30
  31 #define KNI_MAX_DEVICES 32
  32
  33 /* loopback mode */
  34 static char *lo_mode;
  35
  36 /* Kernel thread mode */
  37 static char *kthread_mode;
  38 static uint32_t multiple_kthread_on;
  39
  40 /* Default carrier state for created KNI network interfaces */
  41 static char *carrier;
  42 uint32_t kni_dflt_carrier;
  43
  44 #define KNI_DEV_IN_USE_BIT_NUM 0 /* Bit number for device in use */
  45
  46 static int kni_net_id;
  47
  48 struct kni_net {
  49         unsigned long device_in_use; /* device in use flag */
  50         struct mutex kni_kthread_lock;
  51         struct task_struct *kni_kthread;
  52         struct rw_semaphore kni_list_lock;
  53         struct list_head kni_list_head;
  54 };
  55
  56 static int __net_init
  57 kni_init_net(struct net *net)
  58 {
  59 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
  60         struct kni_net *knet = net_generic(net, kni_net_id);
  61
  62         memset(knet, 0, sizeof(*knet));
  63 #else
  64         struct kni_net *knet;
  65         int ret;
  66
  67         knet = kzalloc(sizeof(struct kni_net), GFP_KERNEL);
  68         if (!knet) {
  69                 ret = -ENOMEM;
  70                 return ret;
  71         }
  72 #endif
  73
  74         /* Clear the bit of device in use */
  75         clear_bit(KNI_DEV_IN_USE_BIT_NUM, &knet->device_in_use);
  76
  77         mutex_init(&knet->kni_kthread_lock);
  78
  79         init_rwsem(&knet->kni_list_lock);
  80         INIT_LIST_HEAD(&knet->kni_list_head);
  81
  82 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
  83         return 0;
  84 #else
  85         ret = net_assign_generic(net, kni_net_id, knet);
  86         if (ret < 0)
  87                 kfree(knet);
  88
  89         return ret;
  90 #endif
  91 }
  92
  93 static void __net_exit
  94 kni_exit_net(struct net *net)
  95 {
  96         struct kni_net *knet __maybe_unused;
  97
  98         knet = net_generic(net, kni_net_id);
  99         mutex_destroy(&knet->kni_kthread_lock);
 100
 101 #ifndef HAVE_SIMPLIFIED_PERNET_OPERATIONS
 102         kfree(knet);
 103 #endif
 104 }
 105
 106 static struct pernet_operations kni_net_ops = {
 107         .init = kni_init_net,
 108         .exit = kni_exit_net,
 109 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
 110         .id   = &kni_net_id,
 111         .size = sizeof(struct kni_net),
 112 #endif
 113 };
 114
 115 static int
 116 kni_thread_single(void *data)
 117 {
 118         struct kni_net *knet = data;
 119         int j;
 120         struct kni_dev *dev;
 121
 122         while (!kthread_should_stop()) {
 123                 down_read(&knet->kni_list_lock);
 124                 for (j = 0; j < KNI_RX_LOOP_NUM; j++) {
 125                         list_for_each_entry(dev, &knet->kni_list_head, list) {
 126                                 kni_net_rx(dev);
 127                                 kni_net_poll_resp(dev);
 128                         }
 129                 }
 130                 up_read(&knet->kni_list_lock);
 131 #ifdef RTE_KNI_PREEMPT_DEFAULT
 132                 /* reschedule out for a while */
 133                 schedule_timeout_interruptible(
 134                         usecs_to_jiffies(KNI_KTHREAD_RESCHEDULE_INTERVAL));
 135 #endif
 136         }
 137
 138         return 0;
 139 }
 140
 141 static int
 142 kni_thread_multiple(void *param)
 143 {
 144         int j;
 145         struct kni_dev *dev = param;
 146
 147         while (!kthread_should_stop()) {
 148                 for (j = 0; j < KNI_RX_LOOP_NUM; j++) {
 149                         kni_net_rx(dev);
 150                         kni_net_poll_resp(dev);
 151                 }
 152 #ifdef RTE_KNI_PREEMPT_DEFAULT
 153                 schedule_timeout_interruptible(
 154                         usecs_to_jiffies(KNI_KTHREAD_RESCHEDULE_INTERVAL));
 155 #endif
 156         }
 157
 158         return 0;
 159 }
 160
 161 static int
 162 kni_open(struct inode *inode, struct file *file)
 163 {
 164         struct net *net = current->nsproxy->net_ns;
 165         struct kni_net *knet = net_generic(net, kni_net_id);
 166
 167         /* kni device can be opened by one user only per netns */
 168         if (test_and_set_bit(KNI_DEV_IN_USE_BIT_NUM, &knet->device_in_use))
 169                 return -EBUSY;
 170
 171         file->private_data = get_net(net);
 172         pr_debug("/dev/kni opened\n");
 173
 174         return 0;
 175 }
 176
 177 static int
 178 kni_dev_remove(struct kni_dev *dev)
 179 {
 180         if (!dev)
 181                 return -ENODEV;
 182
 183         if (dev->net_dev) {
 184                 unregister_netdev(dev->net_dev);
 185                 free_netdev(dev->net_dev);
 186         }
 187
 188         kni_net_release_fifo_phy(dev);
 189
 190         return 0;
 191 }
 192
 193 static int
 194 kni_release(struct inode *inode, struct file *file)
 195 {
 196         struct net *net = file->private_data;
 197         struct kni_net *knet = net_generic(net, kni_net_id);
 198         struct kni_dev *dev, *n;
 199
 200         /* Stop kernel thread for single mode */
 201         if (multiple_kthread_on == 0) {
 202                 mutex_lock(&knet->kni_kthread_lock);
 203                 /* Stop kernel thread */
 204                 if (knet->kni_kthread != NULL) {
 205                         kthread_stop(knet->kni_kthread);
 206                         knet->kni_kthread = NULL;
 207                 }
 208                 mutex_unlock(&knet->kni_kthread_lock);
 209         }
 210
 211         down_write(&knet->kni_list_lock);
 212         list_for_each_entry_safe(dev, n, &knet->kni_list_head, list) {
 213                 /* Stop kernel thread for multiple mode */
 214                 if (multiple_kthread_on && dev->pthread != NULL) {
 215                         kthread_stop(dev->pthread);
 216                         dev->pthread = NULL;
 217                 }
 218
 219                 kni_dev_remove(dev);
 220                 list_del(&dev->list);
 221         }
 222         up_write(&knet->kni_list_lock);
 223
 224         /* Clear the bit of device in use */
 225         clear_bit(KNI_DEV_IN_USE_BIT_NUM, &knet->device_in_use);
 226
 227         put_net(net);
 228         pr_debug("/dev/kni closed\n");
 229
 230         return 0;
 231 }
 232
 233 static int
 234 kni_check_param(struct kni_dev *kni, struct rte_kni_device_info *dev)
 235 {
 236         if (!kni || !dev)
 237                 return -1;
 238
 239         /* Check if network name has been used */
 240         if (!strncmp(kni->name, dev->name, RTE_KNI_NAMESIZE)) {
 241                 pr_err("KNI name %s duplicated\n", dev->name);
 242                 return -1;
 243         }
 244
 245         return 0;
 246 }
 247
 248 static int
 249 kni_run_thread(struct kni_net *knet, struct kni_dev *kni, uint8_t force_bind)
 250 {
 251         /**
 252          * Create a new kernel thread for multiple mode, set its core affinity,
 253          * and finally wake it up.
 254          */
 255         if (multiple_kthread_on) {
 256                 kni->pthread = kthread_create(kni_thread_multiple,
 257                         (void *)kni, "kni_%s", kni->name);
 258                 if (IS_ERR(kni->pthread)) {
 259                         kni_dev_remove(kni);
 260                         return -ECANCELED;
 261                 }
 262
 263                 if (force_bind)
 264                         kthread_bind(kni->pthread, kni->core_id);
 265                 wake_up_process(kni->pthread);
 266         } else {
 267                 mutex_lock(&knet->kni_kthread_lock);
 268
 269                 if (knet->kni_kthread == NULL) {
 270                         knet->kni_kthread = kthread_create(kni_thread_single,
 271                                 (void *)knet, "kni_single");
 272                         if (IS_ERR(knet->kni_kthread)) {
 273                                 mutex_unlock(&knet->kni_kthread_lock);
 274                                 kni_dev_remove(kni);
 275                                 return -ECANCELED;
 276                         }
 277
 278                         if (force_bind)
 279                                 kthread_bind(knet->kni_kthread, kni->core_id);
 280                         wake_up_process(knet->kni_kthread);
 281                 }
 282
 283                 mutex_unlock(&knet->kni_kthread_lock);
 284         }
 285
 286         return 0;
 287 }
 288
 289 static int
 290 kni_ioctl_create(struct net *net, uint32_t ioctl_num,
 291                 unsigned long ioctl_param)
 292 {
 293         struct kni_net *knet = net_generic(net, kni_net_id);
 294         int ret;
 295         struct rte_kni_device_info dev_info;
 296         struct net_device *net_dev = NULL;
 297         struct kni_dev *kni, *dev, *n;
 298
 299         pr_info("Creating kni...\n");
 300         /* Check the buffer size, to avoid warning */
 301         if (_IOC_SIZE(ioctl_num) > sizeof(dev_info))
 302                 return -EINVAL;
 303
 304         /* Copy kni info from user space */
 305         if (copy_from_user(&dev_info, (void *)ioctl_param, sizeof(dev_info)))
 306                 return -EFAULT;
 307
 308         /* Check if name is zero-ended */
 309         if (strnlen(dev_info.name, sizeof(dev_info.name)) == sizeof(dev_info.name)) {
 310                 pr_err("kni.name not zero-terminated");
 311                 return -EINVAL;
 312         }
 313
 314         /**
 315          * Check if the cpu core id is valid for binding.
 316          */
 317         if (dev_info.force_bind && !cpu_online(dev_info.core_id)) {
 318                 pr_err("cpu %u is not online\n", dev_info.core_id);
 319                 return -EINVAL;
 320         }
 321
 322         /* Check if it has been created */
 323         down_read(&knet->kni_list_lock);
 324         list_for_each_entry_safe(dev, n, &knet->kni_list_head, list) {
 325                 if (kni_check_param(dev, &dev_info) < 0) {
 326                         up_read(&knet->kni_list_lock);
 327                         return -EINVAL;
 328                 }
 329         }
 330         up_read(&knet->kni_list_lock);
 331
 332         net_dev = alloc_netdev(sizeof(struct kni_dev), dev_info.name,
 333 #ifdef NET_NAME_USER
 334                                                         NET_NAME_USER,
 335 #endif
 336                                                         kni_net_init);
 337         if (net_dev == NULL) {
 338                 pr_err("error allocating device \"%s\"\n", dev_info.name);
 339                 return -EBUSY;
 340         }
 341
 342         dev_net_set(net_dev, net);
 343
 344         kni = netdev_priv(net_dev);
 345
 346         kni->net_dev = net_dev;
 347         kni->core_id = dev_info.core_id;
 348         strncpy(kni->name, dev_info.name, RTE_KNI_NAMESIZE);
 349
 350         /* Translate user space info into kernel space info */
 351         if (dev_info.iova_mode) {
 352 #ifdef HAVE_IOVA_TO_KVA_MAPPING_SUPPORT
 353                 kni->tx_q = iova_to_kva(current, dev_info.tx_phys);
 354                 kni->rx_q = iova_to_kva(current, dev_info.rx_phys);
 355                 kni->alloc_q = iova_to_kva(current, dev_info.alloc_phys);
 356                 kni->free_q = iova_to_kva(current, dev_info.free_phys);
 357
 358                 kni->req_q = iova_to_kva(current, dev_info.req_phys);
 359                 kni->resp_q = iova_to_kva(current, dev_info.resp_phys);
 360                 kni->sync_va = dev_info.sync_va;
 361                 kni->sync_kva = iova_to_kva(current, dev_info.sync_phys);
 362                 kni->usr_tsk = current;
 363                 kni->iova_mode = 1;
 364 #else
 365                 pr_err("KNI module does not support IOVA to VA translation\n");
 366                 return -EINVAL;
 367 #endif
 368         } else {
 369
 370                 kni->tx_q = phys_to_virt(dev_info.tx_phys);
 371                 kni->rx_q = phys_to_virt(dev_info.rx_phys);
 372                 kni->alloc_q = phys_to_virt(dev_info.alloc_phys);
 373                 kni->free_q = phys_to_virt(dev_info.free_phys);
 374
 375                 kni->req_q = phys_to_virt(dev_info.req_phys);
 376                 kni->resp_q = phys_to_virt(dev_info.resp_phys);
 377                 kni->sync_va = dev_info.sync_va;
 378                 kni->sync_kva = phys_to_virt(dev_info.sync_phys);
 379                 kni->iova_mode = 0;
 380         }
 381
 382         kni->mbuf_size = dev_info.mbuf_size;
 383
 384         pr_debug("tx_phys:      0x%016llx, tx_q addr:      0x%p\n",
 385                 (unsigned long long) dev_info.tx_phys, kni->tx_q);
 386         pr_debug("rx_phys:      0x%016llx, rx_q addr:      0x%p\n",
 387                 (unsigned long long) dev_info.rx_phys, kni->rx_q);
 388         pr_debug("alloc_phys:   0x%016llx, alloc_q addr:   0x%p\n",
 389                 (unsigned long long) dev_info.alloc_phys, kni->alloc_q);
 390         pr_debug("free_phys:    0x%016llx, free_q addr:    0x%p\n",
 391                 (unsigned long long) dev_info.free_phys, kni->free_q);
 392         pr_debug("req_phys:     0x%016llx, req_q addr:     0x%p\n",
 393                 (unsigned long long) dev_info.req_phys, kni->req_q);
 394         pr_debug("resp_phys:    0x%016llx, resp_q addr:    0x%p\n",
 395                 (unsigned long long) dev_info.resp_phys, kni->resp_q);
 396         pr_debug("mbuf_size:    %u\n", kni->mbuf_size);
 397
 398         /* if user has provided a valid mac address */
 399         if (is_valid_ether_addr(dev_info.mac_addr))
 400                 memcpy(net_dev->dev_addr, dev_info.mac_addr, ETH_ALEN);
 401         else
 402                 /*
 403                  * Generate random mac address. eth_random_addr() is the
 404                  * newer version of generating mac address in kernel.
 405                  */
 406                 random_ether_addr(net_dev->dev_addr);
 407
 408         if (dev_info.mtu)
 409                 net_dev->mtu = dev_info.mtu;
 410 #ifdef HAVE_MAX_MTU_PARAM
 411         net_dev->max_mtu = net_dev->mtu;
 412
 413         if (dev_info.min_mtu)
 414                 net_dev->min_mtu = dev_info.min_mtu;
 415
 416         if (dev_info.max_mtu)
 417                 net_dev->max_mtu = dev_info.max_mtu;
 418 #endif
 419
 420         ret = register_netdev(net_dev);
 421         if (ret) {
 422                 pr_err("error %i registering device \"%s\"\n",
 423                                         ret, dev_info.name);
 424                 kni->net_dev = NULL;
 425                 kni_dev_remove(kni);
 426                 free_netdev(net_dev);
 427                 return -ENODEV;
 428         }
 429
 430         netif_carrier_off(net_dev);
 431
 432         ret = kni_run_thread(knet, kni, dev_info.force_bind);
 433         if (ret != 0)
 434                 return ret;
 435
 436         down_write(&knet->kni_list_lock);
 437         list_add(&kni->list, &knet->kni_list_head);
 438         up_write(&knet->kni_list_lock);
 439
 440         return 0;
 441 }
 442
 443 static int
 444 kni_ioctl_release(struct net *net, uint32_t ioctl_num,
 445                 unsigned long ioctl_param)
 446 {
 447         struct kni_net *knet = net_generic(net, kni_net_id);
 448         int ret = -EINVAL;
 449         struct kni_dev *dev, *n;
 450         struct rte_kni_device_info dev_info;
 451
 452         if (_IOC_SIZE(ioctl_num) > sizeof(dev_info))
 453                 return -EINVAL;
 454
 455         if (copy_from_user(&dev_info, (void *)ioctl_param, sizeof(dev_info)))
 456                 return -EFAULT;
 457
 458         /* Release the network device according to its name */
 459         if (strlen(dev_info.name) == 0)
 460                 return -EINVAL;
 461
 462         down_write(&knet->kni_list_lock);
 463         list_for_each_entry_safe(dev, n, &knet->kni_list_head, list) {
 464                 if (strncmp(dev->name, dev_info.name, RTE_KNI_NAMESIZE) != 0)
 465                         continue;
 466
 467                 if (multiple_kthread_on && dev->pthread != NULL) {
 468                         kthread_stop(dev->pthread);
 469                         dev->pthread = NULL;
 470                 }
 471
 472                 kni_dev_remove(dev);
 473                 list_del(&dev->list);
 474                 ret = 0;
 475                 break;
 476         }
 477         up_write(&knet->kni_list_lock);
 478         pr_info("%s release kni named %s\n",
 479                 (ret == 0 ? "Successfully" : "Unsuccessfully"), dev_info.name);
 480
 481         return ret;
 482 }
 483
 484 static int
 485 kni_ioctl(struct inode *inode, uint32_t ioctl_num, unsigned long ioctl_param)
 486 {
 487         int ret = -EINVAL;
 488         struct net *net = current->nsproxy->net_ns;
 489
 490         pr_debug("IOCTL num=0x%0x param=0x%0lx\n", ioctl_num, ioctl_param);
 491
 492         /*
 493          * Switch according to the ioctl called
 494          */
 495         switch (_IOC_NR(ioctl_num)) {
 496         case _IOC_NR(RTE_KNI_IOCTL_TEST):
 497                 /* For test only, not used */
 498                 break;
 499         case _IOC_NR(RTE_KNI_IOCTL_CREATE):
 500                 ret = kni_ioctl_create(net, ioctl_num, ioctl_param);
 501                 break;
 502         case _IOC_NR(RTE_KNI_IOCTL_RELEASE):
 503                 ret = kni_ioctl_release(net, ioctl_num, ioctl_param);
 504                 break;
 505         default:
 506                 pr_debug("IOCTL default\n");
 507                 break;
 508         }
 509
 510         return ret;
 511 }
 512
 513 static int
 514 kni_compat_ioctl(struct inode *inode, uint32_t ioctl_num,
 515                 unsigned long ioctl_param)
 516 {
 517         /* 32 bits app on 64 bits OS to be supported later */
 518         pr_debug("Not implemented.\n");
 519
 520         return -EINVAL;
 521 }
 522
 523 static const struct file_operations kni_fops = {
 524         .owner = THIS_MODULE,
 525         .open = kni_open,
 526         .release = kni_release,
 527         .unlocked_ioctl = (void *)kni_ioctl,
 528         .compat_ioctl = (void *)kni_compat_ioctl,
 529 };
 530
 531 static struct miscdevice kni_misc = {
 532         .minor = MISC_DYNAMIC_MINOR,
 533         .name = KNI_DEVICE,
 534         .fops = &kni_fops,
 535 };
 536
 537 static int __init
 538 kni_parse_kthread_mode(void)
 539 {
 540         if (!kthread_mode)
 541                 return 0;
 542
 543         if (strcmp(kthread_mode, "single") == 0)
 544                 return 0;
 545         else if (strcmp(kthread_mode, "multiple") == 0)
 546                 multiple_kthread_on = 1;
 547         else
 548                 return -1;
 549
 550         return 0;
 551 }
 552
 553 static int __init
 554 kni_parse_carrier_state(void)
 555 {
 556         if (!carrier) {
 557                 kni_dflt_carrier = 0;
 558                 return 0;
 559         }
 560
 561         if (strcmp(carrier, "off") == 0)
 562                 kni_dflt_carrier = 0;
 563         else if (strcmp(carrier, "on") == 0)
 564                 kni_dflt_carrier = 1;
 565         else
 566                 return -1;
 567
 568         return 0;
 569 }
 570
 571 static int __init
 572 kni_init(void)
 573 {
 574         int rc;
 575
 576         if (kni_parse_kthread_mode() < 0) {
 577                 pr_err("Invalid parameter for kthread_mode\n");
 578                 return -EINVAL;
 579         }
 580
 581         if (multiple_kthread_on == 0)
 582                 pr_debug("Single kernel thread for all KNI devices\n");
 583         else
 584                 pr_debug("Multiple kernel thread mode enabled\n");
 585
 586         if (kni_parse_carrier_state() < 0) {
 587                 pr_err("Invalid parameter for carrier\n");
 588                 return -EINVAL;
 589         }
 590
 591         if (kni_dflt_carrier == 0)
 592                 pr_debug("Default carrier state set to off.\n");
 593         else
 594                 pr_debug("Default carrier state set to on.\n");
 595
 596 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
 597         rc = register_pernet_subsys(&kni_net_ops);
 598 #else
 599         rc = register_pernet_gen_subsys(&kni_net_id, &kni_net_ops);
 600 #endif
 601         if (rc)
 602                 return -EPERM;
 603
 604         rc = misc_register(&kni_misc);
 605         if (rc != 0) {
 606                 pr_err("Misc registration failed\n");
 607                 goto out;
 608         }
 609
 610         /* Configure the lo mode according to the input parameter */
 611         kni_net_config_lo_mode(lo_mode);
 612
 613         return 0;
 614
 615 out:
 616 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
 617         unregister_pernet_subsys(&kni_net_ops);
 618 #else
 619         unregister_pernet_gen_subsys(kni_net_id, &kni_net_ops);
 620 #endif
 621         return rc;
 622 }
 623
 624 static void __exit
 625 kni_exit(void)
 626 {
 627         misc_deregister(&kni_misc);
 628 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
 629         unregister_pernet_subsys(&kni_net_ops);
 630 #else
 631         unregister_pernet_gen_subsys(kni_net_id, &kni_net_ops);
 632 #endif
 633 }
 634
 635 module_init(kni_init);
 636 module_exit(kni_exit);
 637
 638 module_param(lo_mode, charp, 0644);
 639 MODULE_PARM_DESC(lo_mode,
 640 "KNI loopback mode (default=lo_mode_none):\n"
 641 "\t\tlo_mode_none        Kernel loopback disabled\n"
 642 "\t\tlo_mode_fifo        Enable kernel loopback with fifo\n"
 643 "\t\tlo_mode_fifo_skb    Enable kernel loopback with fifo and skb buffer\n"
 644 "\t\t"
 645 );
 646
 647 module_param(kthread_mode, charp, 0644);
 648 MODULE_PARM_DESC(kthread_mode,
 649 "Kernel thread mode (default=single):\n"
 650 "\t\tsingle    Single kernel thread mode enabled.\n"
 651 "\t\tmultiple  Multiple kernel thread mode enabled.\n"
 652 "\t\t"
 653 );
 654
 655 module_param(carrier, charp, 0644);
 656 MODULE_PARM_DESC(carrier,
 657 "Default carrier state for KNI interface (default=off):\n"
 658 "\t\toff   Interfaces will be created with carrier state set to off.\n"
 659 "\t\ton    Interfaces will be created with carrier state set to on.\n"
 660 "\t\t"
 661 );