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 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         kni->tx_q = phys_to_virt(dev_info.tx_phys);
 352         kni->rx_q = phys_to_virt(dev_info.rx_phys);
 353         kni->alloc_q = phys_to_virt(dev_info.alloc_phys);
 354         kni->free_q = phys_to_virt(dev_info.free_phys);
 355
 356         kni->req_q = phys_to_virt(dev_info.req_phys);
 357         kni->resp_q = phys_to_virt(dev_info.resp_phys);
 358         kni->sync_va = dev_info.sync_va;
 359         kni->sync_kva = phys_to_virt(dev_info.sync_phys);
 360
 361         kni->mbuf_size = dev_info.mbuf_size;
 362
 363         pr_debug("tx_phys:      0x%016llx, tx_q addr:      0x%p\n",
 364                 (unsigned long long) dev_info.tx_phys, kni->tx_q);
 365         pr_debug("rx_phys:      0x%016llx, rx_q addr:      0x%p\n",
 366                 (unsigned long long) dev_info.rx_phys, kni->rx_q);
 367         pr_debug("alloc_phys:   0x%016llx, alloc_q addr:   0x%p\n",
 368                 (unsigned long long) dev_info.alloc_phys, kni->alloc_q);
 369         pr_debug("free_phys:    0x%016llx, free_q addr:    0x%p\n",
 370                 (unsigned long long) dev_info.free_phys, kni->free_q);
 371         pr_debug("req_phys:     0x%016llx, req_q addr:     0x%p\n",
 372                 (unsigned long long) dev_info.req_phys, kni->req_q);
 373         pr_debug("resp_phys:    0x%016llx, resp_q addr:    0x%p\n",
 374                 (unsigned long long) dev_info.resp_phys, kni->resp_q);
 375         pr_debug("mbuf_size:    %u\n", kni->mbuf_size);
 376
 377         /* if user has provided a valid mac address */
 378         if (is_valid_ether_addr(dev_info.mac_addr))
 379                 memcpy(net_dev->dev_addr, dev_info.mac_addr, ETH_ALEN);
 380         else
 381                 /*
 382                  * Generate random mac address. eth_random_addr() is the
 383                  * newer version of generating mac address in kernel.
 384                  */
 385                 random_ether_addr(net_dev->dev_addr);
 386
 387         if (dev_info.mtu)
 388                 net_dev->mtu = dev_info.mtu;
 389 #ifdef HAVE_MAX_MTU_PARAM
 390         net_dev->max_mtu = net_dev->mtu;
 391 #endif
 392
 393         ret = register_netdev(net_dev);
 394         if (ret) {
 395                 pr_err("error %i registering device \"%s\"\n",
 396                                         ret, dev_info.name);
 397                 kni->net_dev = NULL;
 398                 kni_dev_remove(kni);
 399                 free_netdev(net_dev);
 400                 return -ENODEV;
 401         }
 402
 403         netif_carrier_off(net_dev);
 404
 405         ret = kni_run_thread(knet, kni, dev_info.force_bind);
 406         if (ret != 0)
 407                 return ret;
 408
 409         down_write(&knet->kni_list_lock);
 410         list_add(&kni->list, &knet->kni_list_head);
 411         up_write(&knet->kni_list_lock);
 412
 413         return 0;
 414 }
 415
 416 static int
 417 kni_ioctl_release(struct net *net, uint32_t ioctl_num,
 418                 unsigned long ioctl_param)
 419 {
 420         struct kni_net *knet = net_generic(net, kni_net_id);
 421         int ret = -EINVAL;
 422         struct kni_dev *dev, *n;
 423         struct rte_kni_device_info dev_info;
 424
 425         if (_IOC_SIZE(ioctl_num) > sizeof(dev_info))
 426                 return -EINVAL;
 427
 428         if (copy_from_user(&dev_info, (void *)ioctl_param, sizeof(dev_info)))
 429                 return -EFAULT;
 430
 431         /* Release the network device according to its name */
 432         if (strlen(dev_info.name) == 0)
 433                 return -EINVAL;
 434
 435         down_write(&knet->kni_list_lock);
 436         list_for_each_entry_safe(dev, n, &knet->kni_list_head, list) {
 437                 if (strncmp(dev->name, dev_info.name, RTE_KNI_NAMESIZE) != 0)
 438                         continue;
 439
 440                 if (multiple_kthread_on && dev->pthread != NULL) {
 441                         kthread_stop(dev->pthread);
 442                         dev->pthread = NULL;
 443                 }
 444
 445                 kni_dev_remove(dev);
 446                 list_del(&dev->list);
 447                 ret = 0;
 448                 break;
 449         }
 450         up_write(&knet->kni_list_lock);
 451         pr_info("%s release kni named %s\n",
 452                 (ret == 0 ? "Successfully" : "Unsuccessfully"), dev_info.name);
 453
 454         return ret;
 455 }
 456
 457 static int
 458 kni_ioctl(struct inode *inode, uint32_t ioctl_num, unsigned long ioctl_param)
 459 {
 460         int ret = -EINVAL;
 461         struct net *net = current->nsproxy->net_ns;
 462
 463         pr_debug("IOCTL num=0x%0x param=0x%0lx\n", ioctl_num, ioctl_param);
 464
 465         /*
 466          * Switch according to the ioctl called
 467          */
 468         switch (_IOC_NR(ioctl_num)) {
 469         case _IOC_NR(RTE_KNI_IOCTL_TEST):
 470                 /* For test only, not used */
 471                 break;
 472         case _IOC_NR(RTE_KNI_IOCTL_CREATE):
 473                 ret = kni_ioctl_create(net, ioctl_num, ioctl_param);
 474                 break;
 475         case _IOC_NR(RTE_KNI_IOCTL_RELEASE):
 476                 ret = kni_ioctl_release(net, ioctl_num, ioctl_param);
 477                 break;
 478         default:
 479                 pr_debug("IOCTL default\n");
 480                 break;
 481         }
 482
 483         return ret;
 484 }
 485
 486 static int
 487 kni_compat_ioctl(struct inode *inode, uint32_t ioctl_num,
 488                 unsigned long ioctl_param)
 489 {
 490         /* 32 bits app on 64 bits OS to be supported later */
 491         pr_debug("Not implemented.\n");
 492
 493         return -EINVAL;
 494 }
 495
 496 static const struct file_operations kni_fops = {
 497         .owner = THIS_MODULE,
 498         .open = kni_open,
 499         .release = kni_release,
 500         .unlocked_ioctl = (void *)kni_ioctl,
 501         .compat_ioctl = (void *)kni_compat_ioctl,
 502 };
 503
 504 static struct miscdevice kni_misc = {
 505         .minor = MISC_DYNAMIC_MINOR,
 506         .name = KNI_DEVICE,
 507         .fops = &kni_fops,
 508 };
 509
 510 static int __init
 511 kni_parse_kthread_mode(void)
 512 {
 513         if (!kthread_mode)
 514                 return 0;
 515
 516         if (strcmp(kthread_mode, "single") == 0)
 517                 return 0;
 518         else if (strcmp(kthread_mode, "multiple") == 0)
 519                 multiple_kthread_on = 1;
 520         else
 521                 return -1;
 522
 523         return 0;
 524 }
 525
 526 static int __init
 527 kni_parse_carrier_state(void)
 528 {
 529         if (!carrier) {
 530                 dflt_carrier = 0;
 531                 return 0;
 532         }
 533
 534         if (strcmp(carrier, "off") == 0)
 535                 dflt_carrier = 0;
 536         else if (strcmp(carrier, "on") == 0)
 537                 dflt_carrier = 1;
 538         else
 539                 return -1;
 540
 541         return 0;
 542 }
 543
 544 static int __init
 545 kni_init(void)
 546 {
 547         int rc;
 548
 549         if (kni_parse_kthread_mode() < 0) {
 550                 pr_err("Invalid parameter for kthread_mode\n");
 551                 return -EINVAL;
 552         }
 553
 554         if (multiple_kthread_on == 0)
 555                 pr_debug("Single kernel thread for all KNI devices\n");
 556         else
 557                 pr_debug("Multiple kernel thread mode enabled\n");
 558
 559         if (kni_parse_carrier_state() < 0) {
 560                 pr_err("Invalid parameter for carrier\n");
 561                 return -EINVAL;
 562         }
 563
 564         if (dflt_carrier == 0)
 565                 pr_debug("Default carrier state set to off.\n");
 566         else
 567                 pr_debug("Default carrier state set to on.\n");
 568
 569 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
 570         rc = register_pernet_subsys(&kni_net_ops);
 571 #else
 572         rc = register_pernet_gen_subsys(&kni_net_id, &kni_net_ops);
 573 #endif
 574         if (rc)
 575                 return -EPERM;
 576
 577         rc = misc_register(&kni_misc);
 578         if (rc != 0) {
 579                 pr_err("Misc registration failed\n");
 580                 goto out;
 581         }
 582
 583         /* Configure the lo mode according to the input parameter */
 584         kni_net_config_lo_mode(lo_mode);
 585
 586         return 0;
 587
 588 out:
 589 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
 590         unregister_pernet_subsys(&kni_net_ops);
 591 #else
 592         unregister_pernet_gen_subsys(kni_net_id, &kni_net_ops);
 593 #endif
 594         return rc;
 595 }
 596
 597 static void __exit
 598 kni_exit(void)
 599 {
 600         misc_deregister(&kni_misc);
 601 #ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
 602         unregister_pernet_subsys(&kni_net_ops);
 603 #else
 604         unregister_pernet_gen_subsys(kni_net_id, &kni_net_ops);
 605 #endif
 606 }
 607
 608 module_init(kni_init);
 609 module_exit(kni_exit);
 610
 611 module_param(lo_mode, charp, 0644);
 612 MODULE_PARM_DESC(lo_mode,
 613 "KNI loopback mode (default=lo_mode_none):\n"
 614 "\t\tlo_mode_none        Kernel loopback disabled\n"
 615 "\t\tlo_mode_fifo        Enable kernel loopback with fifo\n"
 616 "\t\tlo_mode_fifo_skb    Enable kernel loopback with fifo and skb buffer\n"
 617 "\t\t"
 618 );
 619
 620 module_param(kthread_mode, charp, 0644);
 621 MODULE_PARM_DESC(kthread_mode,
 622 "Kernel thread mode (default=single):\n"
 623 "\t\tsingle    Single kernel thread mode enabled.\n"
 624 "\t\tmultiple  Multiple kernel thread mode enabled.\n"
 625 "\t\t"
 626 );
 627
 628 module_param(carrier, charp, 0644);
 629 MODULE_PARM_DESC(carrier,
 630 "Default carrier state for KNI interface (default=off):\n"
 631 "\t\toff   Interfaces will be created with carrier state set to off.\n"
 632 "\t\ton    Interfaces will be created with carrier state set to on.\n"
 633 "\t\t"
 634 );