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
  12 #include <rte_errno.h>
  13
  14 #include "mlx5_common.h"
  15 #include "mlx5_common_utils.h"
  16 #include "mlx5_glue.h"
  17
  18 #ifdef MLX5_GLUE
  19 const struct mlx5_glue *mlx5_glue;
  20 #endif
  21
  22 /**
  23  * Get PCI information by sysfs device path.
  24  *
  25  * @param dev_path
  26  *   Pointer to device sysfs folder name.
  27  * @param[out] pci_addr
  28  *   PCI bus address output buffer.
  29  *
  30  * @return
  31  *   0 on success, a negative errno value otherwise and rte_errno is set.
  32  */
  33 int
  34 mlx5_dev_to_pci_addr(const char *dev_path,
  35                      struct rte_pci_addr *pci_addr)
  36 {
  37         FILE *file;
  38         char line[32];
  39         MKSTR(path, "%s/device/uevent", dev_path);
  40
  41         file = fopen(path, "rb");
  42         if (file == NULL) {
  43                 rte_errno = errno;
  44                 return -rte_errno;
  45         }
  46         while (fgets(line, sizeof(line), file) == line) {
  47                 size_t len = strlen(line);
  48                 int ret;
  49
  50                 /* Truncate long lines. */
  51                 if (len == (sizeof(line) - 1))
  52                         while (line[(len - 1)] != '\n') {
  53                                 ret = fgetc(file);
  54                                 if (ret == EOF)
  55                                         break;
  56                                 line[(len - 1)] = ret;
  57                         }
  58                 /* Extract information. */
  59                 if (sscanf(line,
  60                            "PCI_SLOT_NAME="
  61                            "%" SCNx32 ":%" SCNx8 ":%" SCNx8 ".%" SCNx8 "\n",
  62                            &pci_addr->domain,
  63                            &pci_addr->bus,
  64                            &pci_addr->devid,
  65                            &pci_addr->function) == 4) {
  66                         ret = 0;
  67                         break;
  68                 }
  69         }
  70         fclose(file);
  71         return 0;
  72 }
  73
  74 /**
  75  * Extract port name, as a number, from sysfs or netlink information.
  76  *
  77  * @param[in] port_name_in
  78  *   String representing the port name.
  79  * @param[out] port_info_out
  80  *   Port information, including port name as a number and port name
  81  *   type if recognized
  82  *
  83  * @return
  84  *   port_name field set according to recognized name format.
  85  */
  86 void
  87 mlx5_translate_port_name(const char *port_name_in,
  88                          struct mlx5_switch_info *port_info_out)
  89 {
  90         char pf_c1, pf_c2, vf_c1, vf_c2;
  91         char *end;
  92         int sc_items;
  93
  94         /*
  95          * Check for port-name as a string of the form pf0vf0
  96          * (support kernel ver >= 5.0 or OFED ver >= 4.6).
  97          */
  98         sc_items = sscanf(port_name_in, "%c%c%d%c%c%d",
  99                           &pf_c1, &pf_c2, &port_info_out->pf_num,
 100                           &vf_c1, &vf_c2, &port_info_out->port_name);
 101         if (sc_items == 6 &&
 102             pf_c1 == 'p' && pf_c2 == 'f' &&
 103             vf_c1 == 'v' && vf_c2 == 'f') {
 104                 port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_PFVF;
 105                 return;
 106         }
 107         /*
 108          * Check for port-name as a string of the form p0
 109          * (support kernel ver >= 5.0, or OFED ver >= 4.6).
 110          */
 111         sc_items = sscanf(port_name_in, "%c%d",
 112                           &pf_c1, &port_info_out->port_name);
 113         if (sc_items == 2 && pf_c1 == 'p') {
 114                 port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UPLINK;
 115                 return;
 116         }
 117         /* Check for port-name as a number (support kernel ver < 5.0 */
 118         errno = 0;
 119         port_info_out->port_name = strtol(port_name_in, &end, 0);
 120         if (!errno &&
 121             (size_t)(end - port_name_in) == strlen(port_name_in)) {
 122                 port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_LEGACY;
 123                 return;
 124         }
 125         port_info_out->name_type = MLX5_PHYS_PORT_NAME_TYPE_UNKNOWN;
 126 }
 127
 128 #ifdef MLX5_GLUE
 129
 130 /**
 131  * Suffix RTE_EAL_PMD_PATH with "-glue".
 132  *
 133  * This function performs a sanity check on RTE_EAL_PMD_PATH before
 134  * suffixing its last component.
 135  *
 136  * @param buf[out]
 137  *   Output buffer, should be large enough otherwise NULL is returned.
 138  * @param size
 139  *   Size of @p out.
 140  *
 141  * @return
 142  *   Pointer to @p buf or @p NULL in case suffix cannot be appended.
 143  */
 144 static char *
 145 mlx5_glue_path(char *buf, size_t size)
 146 {
 147         static const char *const bad[] = { "/", ".", "..", NULL };
 148         const char *path = RTE_EAL_PMD_PATH;
 149         size_t len = strlen(path);
 150         size_t off;
 151         int i;
 152
 153         while (len && path[len - 1] == '/')
 154                 --len;
 155         for (off = len; off && path[off - 1] != '/'; --off)
 156                 ;
 157         for (i = 0; bad[i]; ++i)
 158                 if (!strncmp(path + off, bad[i], (int)(len - off)))
 159                         goto error;
 160         i = snprintf(buf, size, "%.*s-glue", (int)len, path);
 161         if (i == -1 || (size_t)i >= size)
 162                 goto error;
 163         return buf;
 164 error:
 165         RTE_LOG(ERR, PMD, "unable to append \"-glue\" to last component of"
 166                 " RTE_EAL_PMD_PATH (\"" RTE_EAL_PMD_PATH "\"), please"
 167                 " re-configure DPDK");
 168         return NULL;
 169 }
 170
 171 static int
 172 mlx5_glue_dlopen(void)
 173 {
 174         char glue_path[sizeof(RTE_EAL_PMD_PATH) - 1 + sizeof("-glue")];
 175         void *handle = NULL;
 176
 177         char const *path[] = {
 178                 /*
 179                  * A basic security check is necessary before trusting
 180                  * MLX5_GLUE_PATH, which may override RTE_EAL_PMD_PATH.
 181                  */
 182                 (geteuid() == getuid() && getegid() == getgid() ?
 183                  getenv("MLX5_GLUE_PATH") : NULL),
 184                 /*
 185                  * When RTE_EAL_PMD_PATH is set, use its glue-suffixed
 186                  * variant, otherwise let dlopen() look up libraries on its
 187                  * own.
 188                  */
 189                 (*RTE_EAL_PMD_PATH ?
 190                  mlx5_glue_path(glue_path, sizeof(glue_path)) : ""),
 191         };
 192         unsigned int i = 0;
 193         void **sym;
 194         const char *dlmsg;
 195
 196         while (!handle && i != RTE_DIM(path)) {
 197                 const char *end;
 198                 size_t len;
 199                 int ret;
 200
 201                 if (!path[i]) {
 202                         ++i;
 203                         continue;
 204                 }
 205                 end = strpbrk(path[i], ":;");
 206                 if (!end)
 207                         end = path[i] + strlen(path[i]);
 208                 len = end - path[i];
 209                 ret = 0;
 210                 do {
 211                         char name[ret + 1];
 212
 213                         ret = snprintf(name, sizeof(name), "%.*s%s" MLX5_GLUE,
 214                                        (int)len, path[i],
 215                                        (!len || *(end - 1) == '/') ? "" : "/");
 216                         if (ret == -1)
 217                                 break;
 218                         if (sizeof(name) != (size_t)ret + 1)
 219                                 continue;
 220                         DRV_LOG(DEBUG, "Looking for rdma-core glue as "
 221                                 "\"%s\"", name);
 222                         handle = dlopen(name, RTLD_LAZY);
 223                         break;
 224                 } while (1);
 225                 path[i] = end + 1;
 226                 if (!*end)
 227                         ++i;
 228         }
 229         if (!handle) {
 230                 rte_errno = EINVAL;
 231                 dlmsg = dlerror();
 232                 if (dlmsg)
 233                         DRV_LOG(WARNING, "Cannot load glue library: %s", dlmsg);
 234                 goto glue_error;
 235         }
 236         sym = dlsym(handle, "mlx5_glue");
 237         if (!sym || !*sym) {
 238                 rte_errno = EINVAL;
 239                 dlmsg = dlerror();
 240                 if (dlmsg)
 241                         DRV_LOG(ERR, "Cannot resolve glue symbol: %s", dlmsg);
 242                 goto glue_error;
 243         }
 244         mlx5_glue = *sym;
 245         return 0;
 246
 247 glue_error:
 248         if (handle)
 249                 dlclose(handle);
 250         return -1;
 251 }
 252
 253 #endif
 254
 255 /**
 256  * Initialization routine for run-time dependency on rdma-core.
 257  */
 258 void
 259 mlx5_glue_constructor(void)
 260 {
 261         /*
 262          * RDMAV_HUGEPAGES_SAFE tells ibv_fork_init() we intend to use
 263          * huge pages. Calling ibv_fork_init() during init allows
 264          * applications to use fork() safely for purposes other than
 265          * using this PMD, which is not supported in forked processes.
 266          */
 267         setenv("RDMAV_HUGEPAGES_SAFE", "1", 1);
 268         /* Match the size of Rx completion entry to the size of a cacheline. */
 269         if (RTE_CACHE_LINE_SIZE == 128)
 270                 setenv("MLX5_CQE_SIZE", "128", 0);
 271         /*
 272          * MLX5_DEVICE_FATAL_CLEANUP tells ibv_destroy functions to
 273          * cleanup all the Verbs resources even when the device was removed.
 274          */
 275         setenv("MLX5_DEVICE_FATAL_CLEANUP", "1", 1);
 276
 277 #ifdef MLX5_GLUE
 278         if (mlx5_glue_dlopen() != 0)
 279                 goto glue_error;
 280 #endif
 281
 282 #ifdef RTE_LIBRTE_MLX5_DEBUG
 283         /* Glue structure must not contain any NULL pointers. */
 284         {
 285                 unsigned int i;
 286
 287                 for (i = 0; i != sizeof(*mlx5_glue) / sizeof(void *); ++i)
 288                         MLX5_ASSERT(((const void *const *)mlx5_glue)[i]);
 289         }
 290 #endif
 291         if (strcmp(mlx5_glue->version, MLX5_GLUE_VERSION)) {
 292                 rte_errno = EINVAL;
 293                 DRV_LOG(ERR, "rdma-core glue \"%s\" mismatch: \"%s\" is "
 294                         "required", mlx5_glue->version, MLX5_GLUE_VERSION);
 295                 goto glue_error;
 296         }
 297         mlx5_glue->fork_init();
 298         return;
 299
 300 glue_error:
 301         DRV_LOG(WARNING, "Cannot initialize MLX5 common due to missing"
 302                 " run-time dependency on rdma-core libraries (libibverbs,"
 303                 " libmlx5)");
 304         mlx5_glue = NULL;
 305 }