drivers/net/vdev_netvsc/vdev_netvsc.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright 2017 6WIND S.A.
   3  * Copyright 2017 Mellanox Technologies, Ltd
   4  */
   5
   6 #include <errno.h>
   7 #include <fcntl.h>
   8 #include <inttypes.h>
   9 #include <linux/sockios.h>
  10 #include <linux/netlink.h>
  11 #include <linux/rtnetlink.h>
  12 #include <net/if.h>
  13 #include <net/if_arp.h>
  14 #include <netinet/ip.h>
  15 #include <stdarg.h>
  16 #include <stddef.h>
  17 #include <stdlib.h>
  18 #include <stdint.h>
  19 #include <stdio.h>
  20 #include <string.h>
  21 #include <sys/ioctl.h>
  22 #include <sys/queue.h>
  23 #include <sys/socket.h>
  24 #include <unistd.h>
  25
  26 #include <rte_alarm.h>
  27 #include <rte_bus.h>
  28 #include <rte_bus_vdev.h>
  29 #include <rte_common.h>
  30 #include <rte_config.h>
  31 #include <rte_dev.h>
  32 #include <rte_errno.h>
  33 #include <rte_ethdev.h>
  34 #include <rte_ether.h>
  35 #include <rte_hypervisor.h>
  36 #include <rte_kvargs.h>
  37 #include <rte_log.h>
  38 #include <rte_string_fns.h>
  39
  40 #define VDEV_NETVSC_DRIVER net_vdev_netvsc
  41 #define VDEV_NETVSC_DRIVER_NAME RTE_STR(VDEV_NETVSC_DRIVER)
  42 #define VDEV_NETVSC_DRIVER_NAME_LEN 15
  43 #define VDEV_NETVSC_ARG_IFACE "iface"
  44 #define VDEV_NETVSC_ARG_MAC "mac"
  45 #define VDEV_NETVSC_ARG_FORCE "force"
  46 #define VDEV_NETVSC_ARG_IGNORE "ignore"
  47 #define VDEV_NETVSC_PROBE_MS 1000
  48
  49 #define NETVSC_CLASS_ID "{f8615163-df3e-46c5-913f-f2d2f965ed0e}"
  50 #define NETVSC_MAX_ROUTE_LINE_SIZE 300
  51
  52 #define DRV_LOG(level, ...) \
  53         rte_log(RTE_LOG_ ## level, \
  54                 vdev_netvsc_logtype, \
  55                 RTE_FMT(VDEV_NETVSC_DRIVER_NAME ": " \
  56                         RTE_FMT_HEAD(__VA_ARGS__,) "\n", \
  57                 RTE_FMT_TAIL(__VA_ARGS__,)))
  58
  59 /** Driver-specific log messages type. */
  60 static int vdev_netvsc_logtype;
  61
  62 /** Context structure for a vdev_netvsc instance. */
  63 struct vdev_netvsc_ctx {
  64         LIST_ENTRY(vdev_netvsc_ctx) entry; /**< Next entry in list. */
  65         unsigned int id;                   /**< Unique ID. */
  66         char name[64];                     /**< Unique name. */
  67         char devname[64];                  /**< Fail-safe instance name. */
  68         char devargs[256];                 /**< Fail-safe device arguments. */
  69         char if_name[IF_NAMESIZE];         /**< NetVSC netdevice name. */
  70         unsigned int if_index;             /**< NetVSC netdevice index. */
  71         struct rte_ether_addr if_addr;     /**< NetVSC MAC address. */
  72         int pipe[2];                       /**< Fail-safe communication pipe. */
  73         char yield[256];                   /**< PCI sub-device arguments. */
  74 };
  75
  76 /** Context list is common to all driver instances. */
  77 static LIST_HEAD(, vdev_netvsc_ctx) vdev_netvsc_ctx_list =
  78         LIST_HEAD_INITIALIZER(vdev_netvsc_ctx_list);
  79
  80 /** Number of entries in context list. */
  81 static unsigned int vdev_netvsc_ctx_count;
  82
  83 /** Number of driver instances relying on context list. */
  84 static unsigned int vdev_netvsc_ctx_inst;
  85
  86 /**
  87  * Destroy a vdev_netvsc context instance.
  88  *
  89  * @param ctx
  90  *   Context to destroy.
  91  */
  92 static void
  93 vdev_netvsc_ctx_destroy(struct vdev_netvsc_ctx *ctx)
  94 {
  95         if (ctx->pipe[0] != -1)
  96                 close(ctx->pipe[0]);
  97         if (ctx->pipe[1] != -1)
  98                 close(ctx->pipe[1]);
  99         free(ctx);
 100 }
 101
 102 /**
 103  * Determine if a network interface is NetVSC.
 104  *
 105  * @param[in] iface
 106  *   Pointer to netdevice description structure (name and index).
 107  *
 108  * @return
 109  *   A nonzero value when interface is detected as NetVSC. In case of error,
 110  *   rte_errno is updated and 0 returned.
 111  */
 112 static int
 113 vdev_netvsc_iface_is_netvsc(const struct if_nameindex *iface)
 114 {
 115         static const char temp[] = "/sys/class/net/%s/device/class_id";
 116         char path[sizeof(temp) + IF_NAMESIZE];
 117         FILE *f;
 118         int ret;
 119         int len = 0;
 120
 121         ret = snprintf(path, sizeof(path), temp, iface->if_name);
 122         if (ret == -1 || (size_t)ret >= sizeof(path)) {
 123                 rte_errno = ENOBUFS;
 124                 return 0;
 125         }
 126         f = fopen(path, "r");
 127         if (!f) {
 128                 rte_errno = errno;
 129                 return 0;
 130         }
 131         ret = fscanf(f, NETVSC_CLASS_ID "%n", &len);
 132         if (ret == EOF)
 133                 rte_errno = errno;
 134         ret = len == (int)strlen(NETVSC_CLASS_ID);
 135         fclose(f);
 136         return ret;
 137 }
 138
 139 /**
 140  * Iterate over system network interfaces.
 141  *
 142  * This function runs a given callback function for each netdevice found on
 143  * the system.
 144  *
 145  * @param func
 146  *   Callback function pointer. List traversal is aborted when this function
 147  *   returns a nonzero value.
 148  * @param is_netvsc
 149  *   Indicates the device type to iterate - netvsc or non-netvsc.
 150  * @param ...
 151  *   Variable parameter list passed as @p va_list to @p func.
 152  *
 153  * @return
 154  *   0 when the entire list is traversed successfully, a negative error code
 155  *   in case or failure, or the nonzero value returned by @p func when list
 156  *   traversal is aborted.
 157  */
 158 static int
 159 vdev_netvsc_foreach_iface(int (*func)(const struct if_nameindex *iface,
 160                                       const struct rte_ether_addr *eth_addr,
 161                                       va_list ap), int is_netvsc, ...)
 162 {
 163         struct if_nameindex *iface = if_nameindex();
 164         int s = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
 165         unsigned int i;
 166         int ret = 0;
 167
 168         if (!iface) {
 169                 ret = -ENOBUFS;
 170                 DRV_LOG(ERR, "cannot retrieve system network interfaces");
 171                 goto error;
 172         }
 173         if (s == -1) {
 174                 ret = -errno;
 175                 DRV_LOG(ERR, "cannot open socket: %s", rte_strerror(errno));
 176                 goto error;
 177         }
 178         for (i = 0; iface[i].if_name; ++i) {
 179                 int is_netvsc_ret;
 180                 struct ifreq req;
 181                 struct rte_ether_addr eth_addr;
 182                 va_list ap;
 183
 184                 is_netvsc_ret = vdev_netvsc_iface_is_netvsc(&iface[i]) ? 1 : 0;
 185                 if (is_netvsc ^ is_netvsc_ret)
 186                         continue;
 187                 strlcpy(req.ifr_name, iface[i].if_name, sizeof(req.ifr_name));
 188                 if (ioctl(s, SIOCGIFHWADDR, &req) == -1) {
 189                         DRV_LOG(WARNING, "cannot retrieve information about"
 190                                          " interface \"%s\": %s",
 191                                          req.ifr_name, rte_strerror(errno));
 192                         continue;
 193                 }
 194                 if (req.ifr_hwaddr.sa_family != ARPHRD_ETHER)
 195                         continue;
 196                 memcpy(eth_addr.addr_bytes, req.ifr_hwaddr.sa_data,
 197                        RTE_DIM(eth_addr.addr_bytes));
 198                 va_start(ap, is_netvsc);
 199                 ret = func(&iface[i], &eth_addr, ap);
 200                 va_end(ap);
 201                 if (ret)
 202                         break;
 203         }
 204 error:
 205         if (s != -1)
 206                 close(s);
 207         if (iface)
 208                 if_freenameindex(iface);
 209         return ret;
 210 }
 211
 212 /**
 213  * Determine if a network interface has a route.
 214  *
 215  * @param[in] name
 216  *   Network device name.
 217  * @param[in] family
 218  *   Address family: AF_INET for IPv4 or AF_INET6 for IPv6.
 219  *
 220  * @return
 221  *   1 when interface has a route, negative errno value in case of error and
 222  *   0 otherwise.
 223  */
 224 static int
 225 vdev_netvsc_has_route(const struct if_nameindex *iface,
 226                       const unsigned char family)
 227 {
 228         /*
 229          * The implementation can be simpler by getifaddrs() function usage but
 230          * it works for IPv6 only starting from glibc 2.3.3.
 231          */
 232         char buf[4096];
 233         int len;
 234         int ret = 0;
 235         int res;
 236         int sock;
 237         struct nlmsghdr *retmsg = (struct nlmsghdr *)buf;
 238         struct sockaddr_nl sa;
 239         struct {
 240                 struct nlmsghdr nlhdr;
 241                 struct ifaddrmsg addrmsg;
 242         } msg;
 243
 244         if (!iface || (family != AF_INET && family != AF_INET6)) {
 245                 DRV_LOG(ERR, "%s", rte_strerror(EINVAL));
 246                 return -EINVAL;
 247         }
 248         sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 249         if (sock == -1) {
 250                 DRV_LOG(ERR, "cannot open socket: %s", rte_strerror(errno));
 251                 return -errno;
 252         }
 253         memset(&sa, 0, sizeof(sa));
 254         sa.nl_family = AF_NETLINK;
 255         sa.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR;
 256         res = bind(sock, (struct sockaddr *)&sa, sizeof(sa));
 257         if (res == -1) {
 258                 ret = -errno;
 259                 DRV_LOG(ERR, "cannot bind socket: %s", rte_strerror(errno));
 260                 goto close;
 261         }
 262         memset(&msg, 0, sizeof(msg));
 263         msg.nlhdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
 264         msg.nlhdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
 265         msg.nlhdr.nlmsg_type = RTM_GETADDR;
 266         msg.nlhdr.nlmsg_pid = getpid();
 267         msg.addrmsg.ifa_family = family;
 268         msg.addrmsg.ifa_index = iface->if_index;
 269         res = send(sock, &msg, msg.nlhdr.nlmsg_len, 0);
 270         if (res == -1) {
 271                 ret = -errno;
 272                 DRV_LOG(ERR, "cannot send socket message: %s",
 273                         rte_strerror(errno));
 274                 goto close;
 275         }
 276         memset(buf, 0, sizeof(buf));
 277         len = recv(sock, buf, sizeof(buf), 0);
 278         if (len == -1) {
 279                 ret = -errno;
 280                 DRV_LOG(ERR, "cannot receive socket message: %s",
 281                         rte_strerror(errno));
 282                 goto close;
 283         }
 284         while (NLMSG_OK(retmsg, (unsigned int)len)) {
 285                 struct ifaddrmsg *retaddr =
 286                                 (struct ifaddrmsg *)NLMSG_DATA(retmsg);
 287
 288                 if (retaddr->ifa_family == family &&
 289                     retaddr->ifa_index == iface->if_index) {
 290                         struct rtattr *retrta = IFA_RTA(retaddr);
 291                         int attlen = IFA_PAYLOAD(retmsg);
 292
 293                         while (RTA_OK(retrta, attlen)) {
 294                                 if (retrta->rta_type == IFA_ADDRESS) {
 295                                         ret = 1;
 296                                         DRV_LOG(DEBUG, "interface %s has IP",
 297                                                 iface->if_name);
 298                                         goto close;
 299                                 }
 300                                 retrta = RTA_NEXT(retrta, attlen);
 301                         }
 302                 }
 303                 retmsg = NLMSG_NEXT(retmsg, len);
 304         }
 305 close:
 306         close(sock);
 307         return ret;
 308 }
 309
 310 /**
 311  * Retrieve network interface data from sysfs symbolic link.
 312  *
 313  * @param[out] buf
 314  *   Output data buffer.
 315  * @param size
 316  *   Output buffer size.
 317  * @param[in] if_name
 318  *   Netdevice name.
 319  * @param[in] relpath
 320  *   Symbolic link path relative to netdevice sysfs entry.
 321  *
 322  * @return
 323  *   0 on success, a negative error code otherwise.
 324  */
 325 static int
 326 vdev_netvsc_sysfs_readlink(char *buf, size_t size, const char *if_name,
 327                            const char *relpath)
 328 {
 329         struct vdev_netvsc_ctx *ctx;
 330         char in[RTE_MAX(sizeof(ctx->yield), 256u)];
 331         int ret;
 332
 333         ret = snprintf(in, sizeof(in) - 1, "/sys/class/net/%s/%s",
 334                        if_name, relpath);
 335         if (ret == -1 || (size_t)ret >= sizeof(in))
 336                 return -ENOBUFS;
 337         ret = readlink(in, buf, size);
 338         if (ret == -1)
 339                 return -errno;
 340         if ((size_t)ret >= size - 1)
 341                 return -ENOBUFS;
 342         buf[ret] = '\0';
 343         return 0;
 344 }
 345
 346 /**
 347  * Probe a network interface to associate with vdev_netvsc context.
 348  *
 349  * This function determines if the network device matches the properties of
 350  * the NetVSC interface associated with the vdev_netvsc context and
 351  * communicates its bus address to the fail-safe PMD instance if so.
 352  *
 353  * It is normally used with vdev_netvsc_foreach_iface().
 354  *
 355  * @param[in] iface
 356  *   Pointer to netdevice description structure (name and index).
 357  * @param[in] eth_addr
 358  *   MAC address associated with @p iface.
 359  * @param ap
 360  *   Variable arguments list comprising:
 361  *
 362  *   - struct vdev_netvsc_ctx *ctx:
 363  *     Context to associate network interface with.
 364  *
 365  * @return
 366  *   A nonzero value when interface matches, 0 otherwise or in case of
 367  *   error.
 368  */
 369 static int
 370 vdev_netvsc_device_probe(const struct if_nameindex *iface,
 371                     const struct rte_ether_addr *eth_addr,
 372                     va_list ap)
 373 {
 374         struct vdev_netvsc_ctx *ctx = va_arg(ap, struct vdev_netvsc_ctx *);
 375         char buf[RTE_MAX(sizeof(ctx->yield), 256u)];
 376         const char *addr;
 377         size_t len;
 378         int ret;
 379
 380         /* Skip non-matching or unwanted NetVSC interfaces. */
 381         if (ctx->if_index == iface->if_index) {
 382                 if (!strcmp(ctx->if_name, iface->if_name))
 383                         return 0;
 384                 DRV_LOG(DEBUG,
 385                         "NetVSC interface \"%s\" (index %u) renamed \"%s\"",
 386                         ctx->if_name, ctx->if_index, iface->if_name);
 387                 strlcpy(ctx->if_name, iface->if_name, sizeof(ctx->if_name));
 388                 return 0;
 389         }
 390         if (!is_same_ether_addr(eth_addr, &ctx->if_addr))
 391                 return 0;
 392         /* Look for associated PCI device. */
 393         ret = vdev_netvsc_sysfs_readlink(buf, sizeof(buf), iface->if_name,
 394                                          "device/subsystem");
 395         if (ret)
 396                 return 0;
 397         addr = strrchr(buf, '/');
 398         addr = addr ? addr + 1 : buf;
 399         if (strcmp(addr, "pci"))
 400                 return 0;
 401         ret = vdev_netvsc_sysfs_readlink(buf, sizeof(buf), iface->if_name,
 402                                          "device");
 403         if (ret)
 404                 return 0;
 405         addr = strrchr(buf, '/');
 406         addr = addr ? addr + 1 : buf;
 407         len = strlen(addr);
 408         if (!len)
 409                 return 0;
 410         /* Send PCI device argument to fail-safe PMD instance. */
 411         if (strcmp(addr, ctx->yield))
 412                 DRV_LOG(DEBUG, "associating PCI device \"%s\" with NetVSC"
 413                         " interface \"%s\" (index %u)", addr, ctx->if_name,
 414                         ctx->if_index);
 415         memmove(buf, addr, len + 1);
 416         addr = buf;
 417         buf[len] = '\n';
 418         ret = write(ctx->pipe[1], addr, len + 1);
 419         buf[len] = '\0';
 420         if (ret == -1) {
 421                 if (errno == EINTR || errno == EAGAIN)
 422                         return 1;
 423                 DRV_LOG(WARNING, "cannot associate PCI device name \"%s\" with"
 424                         " interface \"%s\": %s", addr, ctx->if_name,
 425                         rte_strerror(errno));
 426                 return 1;
 427         }
 428         if ((size_t)ret != len + 1) {
 429                 /*
 430                  * Attempt to override previous partial write, no need to
 431                  * recover if that fails.
 432                  */
 433                 ret = write(ctx->pipe[1], "\n", 1);
 434                 (void)ret;
 435                 return 1;
 436         }
 437         fsync(ctx->pipe[1]);
 438         memcpy(ctx->yield, addr, len + 1);
 439         return 1;
 440 }
 441
 442 /**
 443  * Alarm callback that regularly probes system network interfaces.
 444  *
 445  * This callback runs at a frequency determined by VDEV_NETVSC_PROBE_MS as
 446  * long as an vdev_netvsc context instance exists.
 447  *
 448  * @param arg
 449  *   Ignored.
 450  */
 451 static void
 452 vdev_netvsc_alarm(__rte_unused void *arg)
 453 {
 454         struct vdev_netvsc_ctx *ctx;
 455         int ret;
 456
 457         LIST_FOREACH(ctx, &vdev_netvsc_ctx_list, entry) {
 458                 ret = vdev_netvsc_foreach_iface(vdev_netvsc_device_probe, 0,
 459                       ctx);
 460                 if (ret < 0)
 461                         break;
 462         }
 463         if (!vdev_netvsc_ctx_count)
 464                 return;
 465         ret = rte_eal_alarm_set(VDEV_NETVSC_PROBE_MS * 1000,
 466                                 vdev_netvsc_alarm, NULL);
 467         if (ret < 0) {
 468                 DRV_LOG(ERR, "unable to reschedule alarm callback: %s",
 469                         rte_strerror(-ret));
 470         }
 471 }
 472
 473 /**
 474  * Probe a NetVSC interface to generate a vdev_netvsc context from.
 475  *
 476  * This function instantiates vdev_netvsc contexts either for all NetVSC
 477  * devices found on the system or only a subset provided as device
 478  * arguments.
 479  *
 480  * It is normally used with vdev_netvsc_foreach_iface().
 481  *
 482  * @param[in] iface
 483  *   Pointer to netdevice description structure (name and index).
 484  * @param[in] eth_addr
 485  *   MAC address associated with @p iface.
 486  * @param ap
 487  *   Variable arguments list comprising:
 488  *
 489  *   - const char *name:
 490  *     Name associated with current driver instance.
 491  *
 492  *   - struct rte_kvargs *kvargs:
 493  *     Device arguments provided to current driver instance.
 494  *
 495  *   - int force:
 496  *     Accept specified interface even if not detected as NetVSC.
 497  *
 498  *   - unsigned int specified:
 499  *     Number of specific netdevices provided as device arguments.
 500  *
 501  *   - unsigned int *matched:
 502  *     The number of specified netdevices matched by this function.
 503  *
 504  * @return
 505  *   A nonzero value when interface matches, 0 otherwise or in case of
 506  *   error.
 507  */
 508 static int
 509 vdev_netvsc_netvsc_probe(const struct if_nameindex *iface,
 510                          const struct rte_ether_addr *eth_addr,
 511                          va_list ap)
 512 {
 513         const char *name = va_arg(ap, const char *);
 514         struct rte_kvargs *kvargs = va_arg(ap, struct rte_kvargs *);
 515         unsigned int specified = va_arg(ap, unsigned int);
 516         unsigned int *matched = va_arg(ap, unsigned int *);
 517         unsigned int i;
 518         struct vdev_netvsc_ctx *ctx;
 519         int ret;
 520
 521         /* Probe all interfaces when none are specified. */
 522         if (specified) {
 523                 for (i = 0; i != kvargs->count; ++i) {
 524                         const struct rte_kvargs_pair *pair = &kvargs->pairs[i];
 525
 526                         if (!strcmp(pair->key, VDEV_NETVSC_ARG_IFACE)) {
 527                                 if (!strcmp(pair->value, iface->if_name))
 528                                         break;
 529                         } else if (!strcmp(pair->key, VDEV_NETVSC_ARG_MAC)) {
 530                                 struct rte_ether_addr tmp;
 531
 532                                 if (sscanf(pair->value,
 533                                            "%" SCNx8 ":%" SCNx8 ":%" SCNx8 ":"
 534                                            "%" SCNx8 ":%" SCNx8 ":%" SCNx8,
 535                                            &tmp.addr_bytes[0],
 536                                            &tmp.addr_bytes[1],
 537                                            &tmp.addr_bytes[2],
 538                                            &tmp.addr_bytes[3],
 539                                            &tmp.addr_bytes[4],
 540                                            &tmp.addr_bytes[5]) != 6) {
 541                                         DRV_LOG(ERR,
 542                                                 "invalid MAC address format"
 543                                                 " \"%s\"",
 544                                                 pair->value);
 545                                         return -EINVAL;
 546                                 }
 547                                 if (is_same_ether_addr(eth_addr, &tmp))
 548                                         break;
 549                         }
 550                 }
 551                 if (i == kvargs->count)
 552                         return 0;
 553                 ++(*matched);
 554         }
 555         /* Weed out interfaces already handled. */
 556         LIST_FOREACH(ctx, &vdev_netvsc_ctx_list, entry)
 557                 if (ctx->if_index == iface->if_index)
 558                         break;
 559         if (ctx) {
 560                 if (!specified)
 561                         return 0;
 562                 DRV_LOG(WARNING,
 563                         "interface \"%s\" (index %u) is already handled,"
 564                         " skipping",
 565                         iface->if_name, iface->if_index);
 566                 return 0;
 567         }
 568         /* Routed NetVSC should not be probed. */
 569         if (vdev_netvsc_has_route(iface, AF_INET) ||
 570             vdev_netvsc_has_route(iface, AF_INET6)) {
 571                 if (!specified)
 572                         return 0;
 573                 DRV_LOG(WARNING, "probably using routed NetVSC interface \"%s\""
 574                         " (index %u)", iface->if_name, iface->if_index);
 575         }
 576         /* Create interface context. */
 577         ctx = calloc(1, sizeof(*ctx));
 578         if (!ctx) {
 579                 ret = -errno;
 580                 DRV_LOG(ERR, "cannot allocate context for interface \"%s\": %s",
 581                         iface->if_name, rte_strerror(errno));
 582                 goto error;
 583         }
 584         ctx->id = vdev_netvsc_ctx_count;
 585         strlcpy(ctx->if_name, iface->if_name, sizeof(ctx->if_name));
 586         ctx->if_index = iface->if_index;
 587         ctx->if_addr = *eth_addr;
 588         ctx->pipe[0] = -1;
 589         ctx->pipe[1] = -1;
 590         ctx->yield[0] = '\0';
 591         if (pipe(ctx->pipe) == -1) {
 592                 ret = -errno;
 593                 DRV_LOG(ERR,
 594                         "cannot allocate control pipe for interface \"%s\": %s",
 595                         ctx->if_name, rte_strerror(errno));
 596                 goto error;
 597         }
 598         for (i = 0; i != RTE_DIM(ctx->pipe); ++i) {
 599                 int flf = fcntl(ctx->pipe[i], F_GETFL);
 600
 601                 if (flf != -1 &&
 602                     fcntl(ctx->pipe[i], F_SETFL, flf | O_NONBLOCK) != -1)
 603                         continue;
 604                 ret = -errno;
 605                 DRV_LOG(ERR, "cannot toggle non-blocking flag on control file"
 606                         " descriptor #%u (%d): %s", i, ctx->pipe[i],
 607                         rte_strerror(errno));
 608                 goto error;
 609         }
 610         /* Generate virtual device name and arguments. */
 611         i = 0;
 612         ret = snprintf(ctx->name, sizeof(ctx->name), "%s_id%u",
 613                        name, ctx->id);
 614         if (ret == -1 || (size_t)ret >= sizeof(ctx->name))
 615                 ++i;
 616         ret = snprintf(ctx->devname, sizeof(ctx->devname), "net_failsafe_vsc%u",
 617                        ctx->id);
 618         if (ret == -1 || (size_t)ret >= sizeof(ctx->devname))
 619                 ++i;
 620         ret = snprintf(ctx->devargs, sizeof(ctx->devargs),
 621                        "fd(%d),dev(net_tap_vsc%u,remote=%s)",
 622                        ctx->pipe[0], ctx->id, ctx->if_name);
 623         if (ret == -1 || (size_t)ret >= sizeof(ctx->devargs))
 624                 ++i;
 625         if (i) {
 626                 ret = -ENOBUFS;
 627                 DRV_LOG(ERR, "generated virtual device name or argument list"
 628                         " too long for interface \"%s\"", ctx->if_name);
 629                 goto error;
 630         }
 631         /* Request virtual device generation. */
 632         DRV_LOG(DEBUG, "generating virtual device \"%s\" with arguments \"%s\"",
 633                 ctx->devname, ctx->devargs);
 634         vdev_netvsc_foreach_iface(vdev_netvsc_device_probe, 0, ctx);
 635         ret = rte_eal_hotplug_add("vdev", ctx->devname, ctx->devargs);
 636         if (ret)
 637                 goto error;
 638         LIST_INSERT_HEAD(&vdev_netvsc_ctx_list, ctx, entry);
 639         ++vdev_netvsc_ctx_count;
 640         DRV_LOG(DEBUG, "added NetVSC interface \"%s\" to context list",
 641                 ctx->if_name);
 642         return 0;
 643 error:
 644         if (ctx)
 645                 vdev_netvsc_ctx_destroy(ctx);
 646         return ret;
 647 }
 648
 649 /**
 650  * Probe NetVSC interfaces.
 651  *
 652  * This function probes system netdevices according to the specified device
 653  * arguments and starts a periodic alarm callback to notify the resulting
 654  * fail-safe PMD instances of their sub-devices whereabouts.
 655  *
 656  * @param dev
 657  *   Virtual device context for driver instance.
 658  *
 659  * @return
 660  *    Always 0, even in case of errors.
 661  */
 662 static int
 663 vdev_netvsc_vdev_probe(struct rte_vdev_device *dev)
 664 {
 665         static const char *const vdev_netvsc_arg[] = {
 666                 VDEV_NETVSC_ARG_IFACE,
 667                 VDEV_NETVSC_ARG_MAC,
 668                 VDEV_NETVSC_ARG_FORCE,
 669                 VDEV_NETVSC_ARG_IGNORE,
 670                 NULL,
 671         };
 672         const char *name = rte_vdev_device_name(dev);
 673         const char *args = rte_vdev_device_args(dev);
 674         struct rte_kvargs *kvargs = rte_kvargs_parse(args ? args : "",
 675                                                      vdev_netvsc_arg);
 676         unsigned int specified = 0;
 677         unsigned int matched = 0;
 678         int force = 0;
 679         int ignore = 0;
 680         unsigned int i;
 681         int ret;
 682
 683         DRV_LOG(DEBUG, "invoked as \"%s\", using arguments \"%s\"", name, args);
 684         if (!kvargs) {
 685                 DRV_LOG(ERR, "cannot parse arguments list");
 686                 goto error;
 687         }
 688         for (i = 0; i != kvargs->count; ++i) {
 689                 const struct rte_kvargs_pair *pair = &kvargs->pairs[i];
 690
 691                 if (!strcmp(pair->key, VDEV_NETVSC_ARG_FORCE))
 692                         force = !!atoi(pair->value);
 693                 else if (!strcmp(pair->key, VDEV_NETVSC_ARG_IGNORE))
 694                         ignore = !!atoi(pair->value);
 695                 else if (!strcmp(pair->key, VDEV_NETVSC_ARG_IFACE) ||
 696                          !strcmp(pair->key, VDEV_NETVSC_ARG_MAC))
 697                         ++specified;
 698         }
 699         if (ignore) {
 700                 if (kvargs)
 701                         rte_kvargs_free(kvargs);
 702                 return 0;
 703         }
 704         if (specified > 1) {
 705                 DRV_LOG(ERR, "More than one way used to specify the netvsc"
 706                         " device.");
 707                 goto error;
 708         }
 709         rte_eal_alarm_cancel(vdev_netvsc_alarm, NULL);
 710         /* Gather interfaces. */
 711         ret = vdev_netvsc_foreach_iface(vdev_netvsc_netvsc_probe, 1, name,
 712                                         kvargs, specified, &matched);
 713         if (ret < 0)
 714                 goto error;
 715         if (specified && matched < specified) {
 716                 if (!force) {
 717                         DRV_LOG(ERR, "Cannot find the specified netvsc device");
 718                         goto error;
 719                 }
 720                 /* Try to force probing on non-netvsc specified device. */
 721                 if (vdev_netvsc_foreach_iface(vdev_netvsc_netvsc_probe, 0, name,
 722                                               kvargs, specified, &matched) < 0)
 723                         goto error;
 724                 if (matched < specified) {
 725                         DRV_LOG(ERR, "Cannot find the specified device");
 726                         goto error;
 727                 }
 728                 DRV_LOG(WARNING, "non-netvsc device was probed as netvsc");
 729         }
 730         ret = rte_eal_alarm_set(VDEV_NETVSC_PROBE_MS * 1000,
 731                                 vdev_netvsc_alarm, NULL);
 732         if (ret < 0) {
 733                 DRV_LOG(ERR, "unable to schedule alarm callback: %s",
 734                         rte_strerror(-ret));
 735                 goto error;
 736         }
 737 error:
 738         if (kvargs)
 739                 rte_kvargs_free(kvargs);
 740         ++vdev_netvsc_ctx_inst;
 741         return 0;
 742 }
 743
 744 /**
 745  * Remove driver instance.
 746  *
 747  * The alarm callback and underlying vdev_netvsc context instances are only
 748  * destroyed after the last PMD instance is removed.
 749  *
 750  * @param dev
 751  *   Virtual device context for driver instance.
 752  *
 753  * @return
 754  *   Always 0.
 755  */
 756 static int
 757 vdev_netvsc_vdev_remove(__rte_unused struct rte_vdev_device *dev)
 758 {
 759         if (--vdev_netvsc_ctx_inst)
 760                 return 0;
 761         rte_eal_alarm_cancel(vdev_netvsc_alarm, NULL);
 762         while (!LIST_EMPTY(&vdev_netvsc_ctx_list)) {
 763                 struct vdev_netvsc_ctx *ctx = LIST_FIRST(&vdev_netvsc_ctx_list);
 764
 765                 LIST_REMOVE(ctx, entry);
 766                 --vdev_netvsc_ctx_count;
 767                 vdev_netvsc_ctx_destroy(ctx);
 768         }
 769         return 0;
 770 }
 771
 772 /** Virtual device descriptor. */
 773 static struct rte_vdev_driver vdev_netvsc_vdev = {
 774         .probe = vdev_netvsc_vdev_probe,
 775         .remove = vdev_netvsc_vdev_remove,
 776 };
 777
 778 RTE_PMD_REGISTER_VDEV(VDEV_NETVSC_DRIVER, vdev_netvsc_vdev);
 779 RTE_PMD_REGISTER_ALIAS(VDEV_NETVSC_DRIVER, eth_vdev_netvsc);
 780 RTE_PMD_REGISTER_PARAM_STRING(net_vdev_netvsc,
 781                               VDEV_NETVSC_ARG_IFACE "=<string> "
 782                               VDEV_NETVSC_ARG_MAC "=<string> "
 783                               VDEV_NETVSC_ARG_FORCE "=<int> "
 784                               VDEV_NETVSC_ARG_IGNORE "=<int>");
 785
 786 /** Initialize driver log type. */
 787 RTE_INIT(vdev_netvsc_init_log)
 788 {
 789         vdev_netvsc_logtype = rte_log_register("pmd.net.vdev_netvsc");
 790         if (vdev_netvsc_logtype >= 0)
 791                 rte_log_set_level(vdev_netvsc_logtype, RTE_LOG_NOTICE);
 792 }
 793
 794 /** Compare function for vdev find device operation. */
 795 static int
 796 vdev_netvsc_cmp_rte_device(const struct rte_device *dev1,
 797                            __rte_unused const void *_dev2)
 798 {
 799         return strncmp(dev1->devargs->name, VDEV_NETVSC_DRIVER_NAME,
 800                        VDEV_NETVSC_DRIVER_NAME_LEN);
 801 }
 802
 803 /**
 804  * A callback called by vdev bus scan function to ensure this driver probing
 805  * automatically in Hyper-V VM system unless it already exists in the
 806  * devargs list.
 807  */
 808 static void
 809 vdev_netvsc_scan_callback(__rte_unused void *arg)
 810 {
 811         struct rte_device *dev;
 812         struct rte_devargs *devargs;
 813         struct rte_bus *vbus = rte_bus_find_by_name("vdev");
 814
 815         RTE_EAL_DEVARGS_FOREACH("vdev", devargs)
 816                 if (!strncmp(devargs->name, VDEV_NETVSC_DRIVER_NAME,
 817                              VDEV_NETVSC_DRIVER_NAME_LEN))
 818                         return;
 819
 820         dev = vbus->find_device(NULL, vdev_netvsc_cmp_rte_device,
 821                                 VDEV_NETVSC_DRIVER_NAME);
 822         if (dev)
 823                 return;
 824         if (rte_devargs_add(RTE_DEVTYPE_VIRTUAL, VDEV_NETVSC_DRIVER_NAME))
 825                 DRV_LOG(ERR, "unable to add netvsc devargs.");
 826 }
 827
 828 /** Initialize the custom scan. */
 829 RTE_INIT(vdev_netvsc_custom_scan_add)
 830 {
 831         if (rte_hypervisor_get() == RTE_HYPERVISOR_HYPERV)
 832                 rte_vdev_add_custom_scan(vdev_netvsc_scan_callback, NULL);
 833 }