drivers/common/mlx5/linux/mlx5_common_os.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright 2020 Mellanox Technologies, Ltd
   3  */
   4
   5 #include <unistd.h>
   6 #include <string.h>
   7 #include <stdio.h>
   8 #ifdef RTE_IBVERBS_LINK_DLOPEN
   9 #include <dlfcn.h>
  10 #endif
  11 #include <dirent.h>
  12 #include <net/if.h>
  13
  14 #include <rte_errno.h>
  15 #include <rte_string_fns.h>
  16
  17 #include "mlx5_common.h"
  18 #include "mlx5_common_utils.h"
  19 #include "mlx5_glue.h"
  20
  21 #ifdef MLX5_GLUE
  22 const struct mlx5_glue *mlx5_glue;
  23 #endif
  24
  25 /**
  26  * Get PCI information by sysfs device path.
  27  *
  28  * @param dev_path
  29  *   Pointer to device sysfs folder name.
  30  * @param[out] pci_addr
  31  *   PCI bus address output buffer.
  32  *
  33  * @return
  34  *   0 on success, a negative errno value otherwise and rte_errno is set.
  35  */
  36 int
  37 mlx5_dev_to_pci_addr(const char *dev_path,
  38                      struct rte_pci_addr *pci_addr)
  39 {
  40         FILE *file;
  41         char line[32];
  42         MKSTR(path, "%s/device/uevent", dev_path);
  43
  44         file = fopen(path, "rb");
  45         if (file == NULL) {
  46                 rte_errno = errno;
  47                 return -rte_errno;
  48         }
  49         while (fgets(line, sizeof(line), file) == line) {
  50                 size_t len = strlen(line);
  51                 int ret;
  52
  53                 /* Truncate long lines. */
  54                 if (len == (sizeof(line) - 1))
  55                         while (line[(len - 1)] != '\n') {
  56                                 ret = fgetc(file);
  57                                 if (ret == EOF)
  58                                         break;
  59                                 line[(len - 1)] = ret;
  60                         }
  61                 /* Extract information. */
  62                 if (sscanf(line,
  63                            "PCI_SLOT_NAME="
  64                            "%" SCNx32 ":%" SCNx8 ":%" SCNx8 ".%" SCNx8 "\n",
  65                            &pci_addr->domain,
  66                            &pci_addr->bus,
  67                            &pci_addr->devid,
  68                            &pci_addr->function) == 4) {
  69                         ret = 0;
  70                         break;
  71                 }
  72         }
  73         fclose(file);
  74         return 0;
  75 }
  76
  77 /**
  78  * Extract port name, as a number, from sysfs or netlink information.
  79  *
  80  * @param[in] port_name_in
  81  *   String representing the port name.
  82  * @param[out] port_info_out
  83  *   Port information, including port name as a number and port name
  84  *   type if recognized
  85  *
  86  * @return
  87  *   port_name field set according to recognized name format.
  88  */
  89 void
  90 mlx5_translate_port_name(const char *port_name_in,
  91                          struct mlx5_switch_info *port_info_out)
  92 {
  93         char pf_c1, pf_c2, vf_c1, vf_c2;
  94         char *end;
  95         int sc_items;
  96
  97         /*
  98          * Check for port-name as a string of the form pf0vf0
  99          * (support kernel ver >= 5.0 or OFED ver >= 4.6).
 100          */
 101         sc_items = sscanf(port_name_in, "%c%c%d%c%c%d",
 102                           &pf_c1, &pf_c2, &port_info_out->pf_num,
 103                           &vf_c1, &vf_c2, &port_info_out->port_name);
 104         if (sc_items == 6 &&
 105             pf_c1 == 'p' && pf_c2 == 'f' &&
 106             vf_c1 == 'v' && vf_c2 == 'f') {
 107                 port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_PFVF;
 108                 return;
 109         }
 110         /*
 111          * Check for port-name as a string of the form p0
 112          * (support kernel ver >= 5.0, or OFED ver >= 4.6).
 113          */
 114         sc_items = sscanf(port_name_in, "%c%d",
 115                           &pf_c1, &port_info_out->port_name);
 116         if (sc_items == 2 && pf_c1 == 'p') {
 117                 port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UPLINK;
 118                 return;
 119         }
 120         /* Check for port-name as a number (support kernel ver < 5.0 */
 121         errno = 0;
 122         port_info_out->port_name = strtol(port_name_in, &end, 0);
 123         if (!errno &&
 124             (size_t)(end - port_name_in) == strlen(port_name_in)) {
 125                 port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_LEGACY;
 126                 return;
 127         }
 128         port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UNKNOWN;
 129 }
 130
 131 /**
 132  * Get kernel interface name from IB device path.
 133  *
 134  * @param[in] ibdev_path
 135  *   Pointer to IB device path.
 136  * @param[out] ifname
 137  *   Interface name output buffer.
 138  *
 139  * @return
 140  *   0 on success, a negative errno value otherwise and rte_errno is set.
 141  */
 142 int
 143 mlx5_get_ifname_sysfs(const char *ibdev_path, char *ifname)
 144 {
 145         DIR *dir;
 146         struct dirent *dent;
 147         unsigned int dev_type = 0;
 148         unsigned int dev_port_prev = ~0u;
 149         char match[IF_NAMESIZE] = "";
 150
 151         MLX5_ASSERT(ibdev_path);
 152         {
 153                 MKSTR(path, "%s/device/net", ibdev_path);
 154
 155                 dir = opendir(path);
 156                 if (dir == NULL) {
 157                         rte_errno = errno;
 158                         return -rte_errno;
 159                 }
 160         }
 161         while ((dent = readdir(dir)) != NULL) {
 162                 char *name = dent->d_name;
 163                 FILE *file;
 164                 unsigned int dev_port;
 165                 int r;
 166
 167                 if ((name[0] == '.') &&
 168                     ((name[1] == '\0') ||
 169                      ((name[1] == '.') && (name[2] == '\0'))))
 170                         continue;
 171
 172                 MKSTR(path, "%s/device/net/%s/%s",
 173                       ibdev_path, name,
 174                       (dev_type ? "dev_id" : "dev_port"));
 175
 176                 file = fopen(path, "rb");
 177                 if (file == NULL) {
 178                         if (errno != ENOENT)
 179                                 continue;
 180                         /*
 181                          * Switch to dev_id when dev_port does not exist as
 182                          * is the case with Linux kernel versions < 3.15.
 183                          */
 184 try_dev_id:
 185                         match[0] = '\0';
 186                         if (dev_type)
 187                                 break;
 188                         dev_type = 1;
 189                         dev_port_prev = ~0u;
 190                         rewinddir(dir);
 191                         continue;
 192                 }
 193                 r = fscanf(file, (dev_type ? "%x" : "%u"), &dev_port);
 194                 fclose(file);
 195                 if (r != 1)
 196                         continue;
 197                 /*
 198                  * Switch to dev_id when dev_port returns the same value for
 199                  * all ports. May happen when using a MOFED release older than
 200                  * 3.0 with a Linux kernel >= 3.15.
 201                  */
 202                 if (dev_port == dev_port_prev)
 203                         goto try_dev_id;
 204                 dev_port_prev = dev_port;
 205                 if (dev_port == 0)
 206                         strlcpy(match, name, IF_NAMESIZE);
 207         }
 208         closedir(dir);
 209         if (match[0] == '\0') {
 210                 rte_errno = ENOENT;
 211                 return -rte_errno;
 212         }
 213         strncpy(ifname, match, IF_NAMESIZE);
 214         return 0;
 215 }
 216
 217 #ifdef MLX5_GLUE
 218
 219 /**
 220  * Suffix RTE_EAL_PMD_PATH with "-glue".
 221  *
 222  * This function performs a sanity check on RTE_EAL_PMD_PATH before
 223  * suffixing its last component.
 224  *
 225  * @param buf[out]
 226  *   Output buffer, should be large enough otherwise NULL is returned.
 227  * @param size
 228  *   Size of @p out.
 229  *
 230  * @return
 231  *   Pointer to @p buf or @p NULL in case suffix cannot be appended.
 232  */
 233 static char *
 234 mlx5_glue_path(char *buf, size_t size)
 235 {
 236         static const char *const bad[] = { "/", ".", "..", NULL };
 237         const char *path = RTE_EAL_PMD_PATH;
 238         size_t len = strlen(path);
 239         size_t off;
 240         int i;
 241
 242         while (len && path[len - 1] == '/')
 243                 --len;
 244         for (off = len; off && path[off - 1] != '/'; --off)
 245                 ;
 246         for (i = 0; bad[i]; ++i)
 247                 if (!strncmp(path + off, bad[i], (int)(len - off)))
 248                         goto error;
 249         i = snprintf(buf, size, "%.*s-glue", (int)len, path);
 250         if (i == -1 || (size_t)i >= size)
 251                 goto error;
 252         return buf;
 253 error:
 254         RTE_LOG(ERR, PMD, "unable to append \"-glue\" to last component of"
 255                 " RTE_EAL_PMD_PATH (\"" RTE_EAL_PMD_PATH "\"), please"
 256                 " re-configure DPDK");
 257         return NULL;
 258 }
 259
 260 static int
 261 mlx5_glue_dlopen(void)
 262 {
 263         char glue_path[sizeof(RTE_EAL_PMD_PATH) - 1 + sizeof("-glue")];
 264         void *handle = NULL;
 265
 266         char const *path[] = {
 267                 /*
 268                  * A basic security check is necessary before trusting
 269                  * MLX5_GLUE_PATH, which may override RTE_EAL_PMD_PATH.
 270                  */
 271                 (geteuid() == getuid() && getegid() == getgid() ?
 272                  getenv("MLX5_GLUE_PATH") : NULL),
 273                 /*
 274                  * When RTE_EAL_PMD_PATH is set, use its glue-suffixed
 275                  * variant, otherwise let dlopen() look up libraries on its
 276                  * own.
 277                  */
 278                 (*RTE_EAL_PMD_PATH ?
 279                  mlx5_glue_path(glue_path, sizeof(glue_path)) : ""),
 280         };
 281         unsigned int i = 0;
 282         void **sym;
 283         const char *dlmsg;
 284
 285         while (!handle && i != RTE_DIM(path)) {
 286                 const char *end;
 287                 size_t len;
 288                 int ret;
 289
 290                 if (!path[i]) {
 291                         ++i;
 292                         continue;
 293                 }
 294                 end = strpbrk(path[i], ":;");
 295                 if (!end)
 296                         end = path[i] + strlen(path[i]);
 297                 len = end - path[i];
 298                 ret = 0;
 299                 do {
 300                         char name[ret + 1];
 301
 302                         ret = snprintf(name, sizeof(name), "%.*s%s" MLX5_GLUE,
 303                                        (int)len, path[i],
 304                                        (!len || *(end - 1) == '/') ? "" : "/");
 305                         if (ret == -1)
 306                                 break;
 307                         if (sizeof(name) != (size_t)ret + 1)
 308                                 continue;
 309                         DRV_LOG(DEBUG, "Looking for rdma-core glue as "
 310                                 "\"%s\"", name);
 311                         handle = dlopen(name, RTLD_LAZY);
 312                         break;
 313                 } while (1);
 314                 path[i] = end + 1;
 315                 if (!*end)
 316                         ++i;
 317         }
 318         if (!handle) {
 319                 rte_errno = EINVAL;
 320                 dlmsg = dlerror();
 321                 if (dlmsg)
 322                         DRV_LOG(WARNING, "Cannot load glue library: %s", dlmsg);
 323                 goto glue_error;
 324         }
 325         sym = dlsym(handle, "mlx5_glue");
 326         if (!sym || !*sym) {
 327                 rte_errno = EINVAL;
 328                 dlmsg = dlerror();
 329                 if (dlmsg)
 330                         DRV_LOG(ERR, "Cannot resolve glue symbol: %s", dlmsg);
 331                 goto glue_error;
 332         }
 333         mlx5_glue = *sym;
 334         return 0;
 335
 336 glue_error:
 337         if (handle)
 338                 dlclose(handle);
 339         return -1;
 340 }
 341
 342 #endif
 343
 344 /**
 345  * Initialization routine for run-time dependency on rdma-core.
 346  */
 347 void
 348 mlx5_glue_constructor(void)
 349 {
 350         /*
 351          * RDMAV_HUGEPAGES_SAFE tells ibv_fork_init() we intend to use
 352          * huge pages. Calling ibv_fork_init() during init allows
 353          * applications to use fork() safely for purposes other than
 354          * using this PMD, which is not supported in forked processes.
 355          */
 356         setenv("RDMAV_HUGEPAGES_SAFE", "1", 1);
 357         /* Match the size of Rx completion entry to the size of a cacheline. */
 358         if (RTE_CACHE_LINE_SIZE == 128)
 359                 setenv("MLX5_CQE_SIZE", "128", 0);
 360         /*
 361          * MLX5_DEVICE_FATAL_CLEANUP tells ibv_destroy functions to
 362          * cleanup all the Verbs resources even when the device was removed.
 363          */
 364         setenv("MLX5_DEVICE_FATAL_CLEANUP", "1", 1);
 365
 366 #ifdef MLX5_GLUE
 367         if (mlx5_glue_dlopen() != 0)
 368                 goto glue_error;
 369 #endif
 370
 371 #ifdef RTE_LIBRTE_MLX5_DEBUG
 372         /* Glue structure must not contain any NULL pointers. */
 373         {
 374                 unsigned int i;
 375
 376                 for (i = 0; i != sizeof(*mlx5_glue) / sizeof(void *); ++i)
 377                         MLX5_ASSERT(((const void *const *)mlx5_glue)[i]);
 378         }
 379 #endif
 380         if (strcmp(mlx5_glue->version, MLX5_GLUE_VERSION)) {
 381                 rte_errno = EINVAL;
 382                 DRV_LOG(ERR, "rdma-core glue \"%s\" mismatch: \"%s\" is "
 383                         "required", mlx5_glue->version, MLX5_GLUE_VERSION);
 384                 goto glue_error;
 385         }
 386         mlx5_glue->fork_init();
 387         return;
 388
 389 glue_error:
 390         DRV_LOG(WARNING, "Cannot initialize MLX5 common due to missing"
 391                 " run-time dependency on rdma-core libraries (libibverbs,"
 392                 " libmlx5)");
 393         mlx5_glue = NULL;
 394 }
 395