drivers/common/mlx5/mlx5_common.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright 2019 Mellanox Technologies, Ltd
   3  */
   4
   5 #include <dlfcn.h>
   6 #include <unistd.h>
   7 #include <string.h>
   8 #include <stdio.h>
   9
  10 #include <rte_errno.h>
  11
  12 #include "mlx5_common.h"
  13 #include "mlx5_common_utils.h"
  14 #include "mlx5_glue.h"
  15
  16
  17 int mlx5_common_logtype;
  18
  19
  20 /**
  21  * Get PCI information by sysfs device path.
  22  *
  23  * @param dev_path
  24  *   Pointer to device sysfs folder name.
  25  * @param[out] pci_addr
  26  *   PCI bus address output buffer.
  27  *
  28  * @return
  29  *   0 on success, a negative errno value otherwise and rte_errno is set.
  30  */
  31 int
  32 mlx5_dev_to_pci_addr(const char *dev_path,
  33                      struct rte_pci_addr *pci_addr)
  34 {
  35         FILE *file;
  36         char line[32];
  37         MKSTR(path, "%s/device/uevent", dev_path);
  38
  39         file = fopen(path, "rb");
  40         if (file == NULL) {
  41                 rte_errno = errno;
  42                 return -rte_errno;
  43         }
  44         while (fgets(line, sizeof(line), file) == line) {
  45                 size_t len = strlen(line);
  46                 int ret;
  47
  48                 /* Truncate long lines. */
  49                 if (len == (sizeof(line) - 1))
  50                         while (line[(len - 1)] != '\n') {
  51                                 ret = fgetc(file);
  52                                 if (ret == EOF)
  53                                         break;
  54                                 line[(len - 1)] = ret;
  55                         }
  56                 /* Extract information. */
  57                 if (sscanf(line,
  58                            "PCI_SLOT_NAME="
  59                            "%" SCNx32 ":%" SCNx8 ":%" SCNx8 ".%" SCNx8 "\n",
  60                            &pci_addr->domain,
  61                            &pci_addr->bus,
  62                            &pci_addr->devid,
  63                            &pci_addr->function) == 4) {
  64                         ret = 0;
  65                         break;
  66                 }
  67         }
  68         fclose(file);
  69         return 0;
  70 }
  71
  72 static int
  73 mlx5_class_check_handler(__rte_unused const char *key, const char *value,
  74                          void *opaque)
  75 {
  76         enum mlx5_class *ret = opaque;
  77
  78         if (strcmp(value, "vdpa") == 0) {
  79                 *ret = MLX5_CLASS_VDPA;
  80         } else if (strcmp(value, "net") == 0) {
  81                 *ret = MLX5_CLASS_NET;
  82         } else {
  83                 DRV_LOG(ERR, "Invalid mlx5 class %s. Maybe typo in device"
  84                         " class argument setting?", value);
  85                 *ret = MLX5_CLASS_INVALID;
  86         }
  87         return 0;
  88 }
  89
  90 enum mlx5_class
  91 mlx5_class_get(struct rte_devargs *devargs)
  92 {
  93         struct rte_kvargs *kvlist;
  94         const char *key = MLX5_CLASS_ARG_NAME;
  95         enum mlx5_class ret = MLX5_CLASS_NET;
  96
  97         if (devargs == NULL)
  98                 return ret;
  99         kvlist = rte_kvargs_parse(devargs->args, NULL);
 100         if (kvlist == NULL)
 101                 return ret;
 102         if (rte_kvargs_count(kvlist, key))
 103                 rte_kvargs_process(kvlist, key, mlx5_class_check_handler, &ret);
 104         rte_kvargs_free(kvlist);
 105         return ret;
 106 }
 107
 108 #ifdef RTE_IBVERBS_LINK_DLOPEN
 109
 110 /**
 111  * Suffix RTE_EAL_PMD_PATH with "-glue".
 112  *
 113  * This function performs a sanity check on RTE_EAL_PMD_PATH before
 114  * suffixing its last component.
 115  *
 116  * @param buf[out]
 117  *   Output buffer, should be large enough otherwise NULL is returned.
 118  * @param size
 119  *   Size of @p out.
 120  *
 121  * @return
 122  *   Pointer to @p buf or @p NULL in case suffix cannot be appended.
 123  */
 124 static char *
 125 mlx5_glue_path(char *buf, size_t size)
 126 {
 127         static const char *const bad[] = { "/", ".", "..", NULL };
 128         const char *path = RTE_EAL_PMD_PATH;
 129         size_t len = strlen(path);
 130         size_t off;
 131         int i;
 132
 133         while (len && path[len - 1] == '/')
 134                 --len;
 135         for (off = len; off && path[off - 1] != '/'; --off)
 136                 ;
 137         for (i = 0; bad[i]; ++i)
 138                 if (!strncmp(path + off, bad[i], (int)(len - off)))
 139                         goto error;
 140         i = snprintf(buf, size, "%.*s-glue", (int)len, path);
 141         if (i == -1 || (size_t)i >= size)
 142                 goto error;
 143         return buf;
 144 error:
 145         RTE_LOG(ERR, PMD, "unable to append \"-glue\" to last component of"
 146                 " RTE_EAL_PMD_PATH (\"" RTE_EAL_PMD_PATH "\"), please"
 147                 " re-configure DPDK");
 148         return NULL;
 149 }
 150 #endif
 151
 152 /**
 153  * Initialization routine for run-time dependency on rdma-core.
 154  */
 155 RTE_INIT_PRIO(mlx5_glue_init, CLASS)
 156 {
 157         void *handle = NULL;
 158
 159         /* Initialize common log type. */
 160         mlx5_common_logtype = rte_log_register("pmd.common.mlx5");
 161         if (mlx5_common_logtype >= 0)
 162                 rte_log_set_level(mlx5_common_logtype, RTE_LOG_NOTICE);
 163         /*
 164          * RDMAV_HUGEPAGES_SAFE tells ibv_fork_init() we intend to use
 165          * huge pages. Calling ibv_fork_init() during init allows
 166          * applications to use fork() safely for purposes other than
 167          * using this PMD, which is not supported in forked processes.
 168          */
 169         setenv("RDMAV_HUGEPAGES_SAFE", "1", 1);
 170         /* Match the size of Rx completion entry to the size of a cacheline. */
 171         if (RTE_CACHE_LINE_SIZE == 128)
 172                 setenv("MLX5_CQE_SIZE", "128", 0);
 173         /*
 174          * MLX5_DEVICE_FATAL_CLEANUP tells ibv_destroy functions to
 175          * cleanup all the Verbs resources even when the device was removed.
 176          */
 177         setenv("MLX5_DEVICE_FATAL_CLEANUP", "1", 1);
 178         /* The glue initialization was done earlier by mlx5 common library. */
 179 #ifdef RTE_IBVERBS_LINK_DLOPEN
 180         char glue_path[sizeof(RTE_EAL_PMD_PATH) - 1 + sizeof("-glue")];
 181         const char *path[] = {
 182                 /*
 183                  * A basic security check is necessary before trusting
 184                  * MLX5_GLUE_PATH, which may override RTE_EAL_PMD_PATH.
 185                  */
 186                 (geteuid() == getuid() && getegid() == getgid() ?
 187                  getenv("MLX5_GLUE_PATH") : NULL),
 188                 /*
 189                  * When RTE_EAL_PMD_PATH is set, use its glue-suffixed
 190                  * variant, otherwise let dlopen() look up libraries on its
 191                  * own.
 192                  */
 193                 (*RTE_EAL_PMD_PATH ?
 194                  mlx5_glue_path(glue_path, sizeof(glue_path)) : ""),
 195         };
 196         unsigned int i = 0;
 197         void **sym;
 198         const char *dlmsg;
 199
 200         while (!handle && i != RTE_DIM(path)) {
 201                 const char *end;
 202                 size_t len;
 203                 int ret;
 204
 205                 if (!path[i]) {
 206                         ++i;
 207                         continue;
 208                 }
 209                 end = strpbrk(path[i], ":;");
 210                 if (!end)
 211                         end = path[i] + strlen(path[i]);
 212                 len = end - path[i];
 213                 ret = 0;
 214                 do {
 215                         char name[ret + 1];
 216
 217                         ret = snprintf(name, sizeof(name), "%.*s%s" MLX5_GLUE,
 218                                        (int)len, path[i],
 219                                        (!len || *(end - 1) == '/') ? "" : "/");
 220                         if (ret == -1)
 221                                 break;
 222                         if (sizeof(name) != (size_t)ret + 1)
 223                                 continue;
 224                         DRV_LOG(DEBUG, "Looking for rdma-core glue as "
 225                                 "\"%s\"", name);
 226                         handle = dlopen(name, RTLD_LAZY);
 227                         break;
 228                 } while (1);
 229                 path[i] = end + 1;
 230                 if (!*end)
 231                         ++i;
 232         }
 233         if (!handle) {
 234                 rte_errno = EINVAL;
 235                 dlmsg = dlerror();
 236                 if (dlmsg)
 237                         DRV_LOG(WARNING, "Cannot load glue library: %s", dlmsg);
 238                 goto glue_error;
 239         }
 240         sym = dlsym(handle, "mlx5_glue");
 241         if (!sym || !*sym) {
 242                 rte_errno = EINVAL;
 243                 dlmsg = dlerror();
 244                 if (dlmsg)
 245                         DRV_LOG(ERR, "Cannot resolve glue symbol: %s", dlmsg);
 246                 goto glue_error;
 247         }
 248         mlx5_glue = *sym;
 249 #endif /* RTE_IBVERBS_LINK_DLOPEN */
 250 #ifndef NDEBUG
 251         /* Glue structure must not contain any NULL pointers. */
 252         {
 253                 unsigned int i;
 254
 255                 for (i = 0; i != sizeof(*mlx5_glue) / sizeof(void *); ++i)
 256                         assert(((const void *const *)mlx5_glue)[i]);
 257         }
 258 #endif
 259         if (strcmp(mlx5_glue->version, MLX5_GLUE_VERSION)) {
 260                 rte_errno = EINVAL;
 261                 DRV_LOG(ERR, "rdma-core glue \"%s\" mismatch: \"%s\" is "
 262                         "required", mlx5_glue->version, MLX5_GLUE_VERSION);
 263                 goto glue_error;
 264         }
 265         mlx5_glue->fork_init();
 266         return;
 267 glue_error:
 268         if (handle)
 269                 dlclose(handle);
 270         DRV_LOG(WARNING, "Cannot initialize MLX5 common due to missing"
 271                 " run-time dependency on rdma-core libraries (libibverbs,"
 272                 " libmlx5)");
 273         mlx5_glue = NULL;
 274         return;
 275 }