buildtools/pmdinfogen/pmdinfogen.c

   1 /* Postprocess pmd object files to export hw support
   2  *
   3  * Copyright 2016 Neil Horman <nhorman@tuxdriver.com>
   4  * Based in part on modpost.c from the linux kernel
   5  *
   6  * This software may be used and distributed according to the terms
   7  * of the GNU General Public License V2, incorporated herein by reference.
   8  *
   9  */
  10
  11 #define _GNU_SOURCE
  12 #include <stdio.h>
  13 #include <ctype.h>
  14 #include <string.h>
  15 #include <limits.h>
  16 #include <stdbool.h>
  17 #include <errno.h>
  18 #include <rte_common.h>
  19 #include "pmdinfogen.h"
  20
  21 #ifdef RTE_ARCH_64
  22 #define ADDR_SIZE 64
  23 #else
  24 #define ADDR_SIZE 32
  25 #endif
  26
  27
  28 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
  29 {
  30         if (sym)
  31                 return elf->strtab + sym->st_name;
  32         else
  33                 return "(unknown)";
  34 }
  35
  36 static void *grab_file(const char *filename, unsigned long *size)
  37 {
  38         struct stat st;
  39         void *map = MAP_FAILED;
  40         int fd;
  41
  42         fd = open(filename, O_RDONLY);
  43         if (fd < 0)
  44                 return NULL;
  45         if (fstat(fd, &st))
  46                 goto failed;
  47
  48         *size = st.st_size;
  49         map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
  50
  51 failed:
  52         close(fd);
  53         if (map == MAP_FAILED)
  54                 return NULL;
  55         return map;
  56 }
  57
  58 /**
  59   * Return a copy of the next line in a mmap'ed file.
  60   * spaces in the beginning of the line is trimmed away.
  61   * Return a pointer to a static buffer.
  62   **/
  63 static void release_file(void *file, unsigned long size)
  64 {
  65         munmap(file, size);
  66 }
  67
  68
  69 static void *get_sym_value(struct elf_info *info, const Elf_Sym *sym)
  70 {
  71         return RTE_PTR_ADD(info->hdr,
  72                 info->sechdrs[sym->st_shndx].sh_offset + sym->st_value);
  73 }
  74
  75 static Elf_Sym *find_sym_in_symtab(struct elf_info *info,
  76                                    const char *name, Elf_Sym *last)
  77 {
  78         Elf_Sym *idx;
  79         if (last)
  80                 idx = last+1;
  81         else
  82                 idx = info->symtab_start;
  83
  84         for (; idx < info->symtab_stop; idx++) {
  85                 const char *n = sym_name(info, idx);
  86                 if (!strncmp(n, name, strlen(name)))
  87                         return idx;
  88         }
  89         return NULL;
  90 }
  91
  92 static int parse_elf(struct elf_info *info, const char *filename)
  93 {
  94         unsigned int i;
  95         Elf_Ehdr *hdr;
  96         Elf_Shdr *sechdrs;
  97         Elf_Sym  *sym;
  98         int endian;
  99         unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
 100
 101         hdr = grab_file(filename, &info->size);
 102         if (!hdr) {
 103                 perror(filename);
 104                 exit(1);
 105         }
 106         info->hdr = hdr;
 107         if (info->size < sizeof(*hdr)) {
 108                 /* file too small, assume this is an empty .o file */
 109                 return 0;
 110         }
 111         /* Is this a valid ELF file? */
 112         if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
 113             (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
 114             (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
 115             (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
 116                 /* Not an ELF file - silently ignore it */
 117                 return 0;
 118         }
 119
 120         if (!hdr->e_ident[EI_DATA]) {
 121                 /* Unknown endian */
 122                 return 0;
 123         }
 124
 125         endian = hdr->e_ident[EI_DATA];
 126
 127         /* Fix endianness in ELF header */
 128         hdr->e_type      = TO_NATIVE(endian, 16, hdr->e_type);
 129         hdr->e_machine   = TO_NATIVE(endian, 16, hdr->e_machine);
 130         hdr->e_version   = TO_NATIVE(endian, 32, hdr->e_version);
 131         hdr->e_entry     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_entry);
 132         hdr->e_phoff     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_phoff);
 133         hdr->e_shoff     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_shoff);
 134         hdr->e_flags     = TO_NATIVE(endian, 32, hdr->e_flags);
 135         hdr->e_ehsize    = TO_NATIVE(endian, 16, hdr->e_ehsize);
 136         hdr->e_phentsize = TO_NATIVE(endian, 16, hdr->e_phentsize);
 137         hdr->e_phnum     = TO_NATIVE(endian, 16, hdr->e_phnum);
 138         hdr->e_shentsize = TO_NATIVE(endian, 16, hdr->e_shentsize);
 139         hdr->e_shnum     = TO_NATIVE(endian, 16, hdr->e_shnum);
 140         hdr->e_shstrndx  = TO_NATIVE(endian, 16, hdr->e_shstrndx);
 141
 142         sechdrs = RTE_PTR_ADD(hdr, hdr->e_shoff);
 143         info->sechdrs = sechdrs;
 144
 145         /* Check if file offset is correct */
 146         if (hdr->e_shoff > info->size) {
 147                 fprintf(stderr, "section header offset=%lu in file '%s' "
 148                       "is bigger than filesize=%lu\n",
 149                       (unsigned long)hdr->e_shoff,
 150                       filename, info->size);
 151                 return 0;
 152         }
 153
 154         if (hdr->e_shnum == SHN_UNDEF) {
 155                 /*
 156                  * There are more than 64k sections,
 157                  * read count from .sh_size.
 158                  */
 159                 info->num_sections = TO_NATIVE(endian, 32, sechdrs[0].sh_size);
 160         } else {
 161                 info->num_sections = hdr->e_shnum;
 162         }
 163         if (hdr->e_shstrndx == SHN_XINDEX)
 164                 info->secindex_strings =
 165                         TO_NATIVE(endian, 32, sechdrs[0].sh_link);
 166         else
 167                 info->secindex_strings = hdr->e_shstrndx;
 168
 169         /* Fix endianness in section headers */
 170         for (i = 0; i < info->num_sections; i++) {
 171                 sechdrs[i].sh_name      =
 172                         TO_NATIVE(endian, 32, sechdrs[i].sh_name);
 173                 sechdrs[i].sh_type      =
 174                         TO_NATIVE(endian, 32, sechdrs[i].sh_type);
 175                 sechdrs[i].sh_flags     =
 176                         TO_NATIVE(endian, 32, sechdrs[i].sh_flags);
 177                 sechdrs[i].sh_addr      =
 178                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_addr);
 179                 sechdrs[i].sh_offset    =
 180                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_offset);
 181                 sechdrs[i].sh_size      =
 182                         TO_NATIVE(endian, 32, sechdrs[i].sh_size);
 183                 sechdrs[i].sh_link      =
 184                         TO_NATIVE(endian, 32, sechdrs[i].sh_link);
 185                 sechdrs[i].sh_info      =
 186                         TO_NATIVE(endian, 32, sechdrs[i].sh_info);
 187                 sechdrs[i].sh_addralign =
 188                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_addralign);
 189                 sechdrs[i].sh_entsize   =
 190                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_entsize);
 191         }
 192         /* Find symbol table. */
 193         for (i = 1; i < info->num_sections; i++) {
 194                 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
 195
 196                 if (!nobits && sechdrs[i].sh_offset > info->size) {
 197                         fprintf(stderr, "%s is truncated. "
 198                               "sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n",
 199                               filename, (unsigned long)sechdrs[i].sh_offset,
 200                               sizeof(*hdr));
 201                         return 0;
 202                 }
 203
 204                 if (sechdrs[i].sh_type == SHT_SYMTAB) {
 205                         unsigned int sh_link_idx;
 206                         symtab_idx = i;
 207                         info->symtab_start = RTE_PTR_ADD(hdr,
 208                                 sechdrs[i].sh_offset);
 209                         info->symtab_stop  = RTE_PTR_ADD(hdr,
 210                                 sechdrs[i].sh_offset + sechdrs[i].sh_size);
 211                         sh_link_idx = sechdrs[i].sh_link;
 212                         info->strtab       = RTE_PTR_ADD(hdr,
 213                                 sechdrs[sh_link_idx].sh_offset);
 214                 }
 215
 216                 /* 32bit section no. table? ("more than 64k sections") */
 217                 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
 218                         symtab_shndx_idx = i;
 219                         info->symtab_shndx_start = RTE_PTR_ADD(hdr,
 220                                 sechdrs[i].sh_offset);
 221                         info->symtab_shndx_stop  = RTE_PTR_ADD(hdr,
 222                                 sechdrs[i].sh_offset + sechdrs[i].sh_size);
 223                 }
 224         }
 225         if (!info->symtab_start)
 226                 fprintf(stderr, "%s has no symtab?\n", filename);
 227
 228         /* Fix endianness in symbols */
 229         for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
 230                 sym->st_shndx = TO_NATIVE(endian, 16, sym->st_shndx);
 231                 sym->st_name  = TO_NATIVE(endian, 32, sym->st_name);
 232                 sym->st_value = TO_NATIVE(endian, ADDR_SIZE, sym->st_value);
 233                 sym->st_size  = TO_NATIVE(endian, ADDR_SIZE, sym->st_size);
 234         }
 235
 236         if (symtab_shndx_idx != ~0U) {
 237                 Elf32_Word *p;
 238                 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
 239                         fprintf(stderr,
 240                               "%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
 241                               filename, sechdrs[symtab_shndx_idx].sh_link,
 242                               symtab_idx);
 243                 /* Fix endianness */
 244                 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
 245                      p++)
 246                         *p = TO_NATIVE(endian, 32, *p);
 247         }
 248
 249         return 1;
 250 }
 251
 252 static void parse_elf_finish(struct elf_info *info)
 253 {
 254         struct pmd_driver *tmp, *idx = info->drivers;
 255         release_file(info->hdr, info->size);
 256         while (idx) {
 257                 tmp = idx->next;
 258                 free(idx);
 259                 idx = tmp;
 260         }
 261 }
 262
 263 struct opt_tag {
 264         const char *suffix;
 265         const char *json_id;
 266 };
 267
 268 static const struct opt_tag opt_tags[] = {
 269         {"_param_string_export", "params"},
 270 };
 271
 272 static int complete_pmd_entry(struct elf_info *info, struct pmd_driver *drv)
 273 {
 274         const char *tname;
 275         int i;
 276         char tmpsymname[128];
 277         Elf_Sym *tmpsym;
 278
 279         drv->name = get_sym_value(info, drv->name_sym);
 280
 281         for (i = 0; i < PMD_OPT_MAX; i++) {
 282                 memset(tmpsymname, 0, 128);
 283                 sprintf(tmpsymname, "__%s%s", drv->name, opt_tags[i].suffix);
 284                 tmpsym = find_sym_in_symtab(info, tmpsymname, NULL);
 285                 if (!tmpsym)
 286                         continue;
 287                 drv->opt_vals[i] = get_sym_value(info, tmpsym);
 288         }
 289
 290         memset(tmpsymname, 0, 128);
 291         sprintf(tmpsymname, "__%s_pci_tbl_export", drv->name);
 292
 293         tmpsym = find_sym_in_symtab(info, tmpsymname, NULL);
 294
 295
 296         /*
 297          * If this returns NULL, then this is a PMD_VDEV, because
 298          * it has no pci table reference
 299          */
 300         if (!tmpsym) {
 301                 drv->pci_tbl = NULL;
 302                 return 0;
 303         }
 304
 305         tname = get_sym_value(info, tmpsym);
 306         tmpsym = find_sym_in_symtab(info, tname, NULL);
 307         if (!tmpsym)
 308                 return -ENOENT;
 309
 310         drv->pci_tbl = (struct rte_pci_id *)get_sym_value(info, tmpsym);
 311         if (!drv->pci_tbl)
 312                 return -ENOENT;
 313
 314         return 0;
 315 }
 316
 317 static int locate_pmd_entries(struct elf_info *info)
 318 {
 319         Elf_Sym *last = NULL;
 320         struct pmd_driver *new;
 321
 322         info->drivers = NULL;
 323
 324         do {
 325                 new = calloc(sizeof(struct pmd_driver), 1);
 326                 new->name_sym = find_sym_in_symtab(info, "this_pmd_name", last);
 327                 last = new->name_sym;
 328                 if (!new->name_sym)
 329                         free(new);
 330                 else {
 331                         if (complete_pmd_entry(info, new)) {
 332                                 fprintf(stderr,
 333                                         "Failed to complete pmd entry\n");
 334                                 free(new);
 335                         } else {
 336                                 new->next = info->drivers;
 337                                 info->drivers = new;
 338                         }
 339                 }
 340         } while (last);
 341
 342         return 0;
 343 }
 344
 345 static void output_pmd_info_string(struct elf_info *info, char *outfile)
 346 {
 347         FILE *ofd;
 348         struct pmd_driver *drv;
 349         struct rte_pci_id *pci_ids;
 350         int idx = 0;
 351
 352         ofd = fopen(outfile, "w+");
 353         if (!ofd) {
 354                 fprintf(stderr, "Unable to open output file\n");
 355                 return;
 356         }
 357
 358         drv = info->drivers;
 359
 360         while (drv) {
 361                 fprintf(ofd, "const char %s_pmd_info[] __attribute__((used)) = "
 362                         "\"PMD_INFO_STRING= {",
 363                         drv->name);
 364                 fprintf(ofd, "\\\"name\\\" : \\\"%s\\\", ", drv->name);
 365
 366                 for (idx = 0; idx < PMD_OPT_MAX; idx++) {
 367                         if (drv->opt_vals[idx])
 368                                 fprintf(ofd, "\\\"%s\\\" : \\\"%s\\\", ",
 369                                         opt_tags[idx].json_id,
 370                                         drv->opt_vals[idx]);
 371                 }
 372
 373                 pci_ids = drv->pci_tbl;
 374                 fprintf(ofd, "\\\"pci_ids\\\" : [");
 375
 376                 while (pci_ids && pci_ids->device_id) {
 377                         fprintf(ofd, "[%d, %d, %d, %d]",
 378                                 pci_ids->vendor_id, pci_ids->device_id,
 379                                 pci_ids->subsystem_vendor_id,
 380                                 pci_ids->subsystem_device_id);
 381                         pci_ids++;
 382                         if (pci_ids->device_id)
 383                                 fprintf(ofd, ",");
 384                         else
 385                                 fprintf(ofd, " ");
 386                 }
 387                 fprintf(ofd, "]}\";");
 388                 drv = drv->next;
 389         }
 390
 391         fclose(ofd);
 392 }
 393
 394 int main(int argc, char **argv)
 395 {
 396         struct elf_info info;
 397         int rc = 1;
 398
 399         if (argc < 3) {
 400                 fprintf(stderr,
 401                         "usage: pmdinfo <object file> <c output file>\n");
 402                 exit(127);
 403         }
 404         parse_elf(&info, argv[1]);
 405
 406         locate_pmd_entries(&info);
 407
 408         if (info.drivers) {
 409                 output_pmd_info_string(&info, argv[2]);
 410                 rc = 0;
 411         } else {
 412                 fprintf(stderr, "No drivers registered\n");
 413         }
 414
 415         parse_elf_finish(&info);
 416         exit(rc);
 417 }