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 #include <stdio.h>
  12 #include <ctype.h>
  13 #include <string.h>
  14 #include <limits.h>
  15 #include <stdbool.h>
  16 #include <errno.h>
  17 #include <libgen.h>
  18
  19 #include <rte_common.h>
  20 #include "pmdinfogen.h"
  21
  22 #ifdef RTE_ARCH_64
  23 #define ADDR_SIZE 64
  24 #else
  25 #define ADDR_SIZE 32
  26 #endif
  27
  28 static int use_stdin, use_stdout;
  29
  30 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
  31 {
  32         if (sym)
  33                 return elf->strtab + sym->st_name;
  34         else
  35                 return "(unknown)";
  36 }
  37
  38 static void *grab_file(const char *filename, unsigned long *size)
  39 {
  40         struct stat st;
  41         void *map = MAP_FAILED;
  42         int fd = -1;
  43
  44         if (!use_stdin) {
  45                 fd = open(filename, O_RDONLY);
  46                 if (fd < 0)
  47                         return NULL;
  48         } else {
  49                 /* from stdin, use a temporary file to mmap */
  50                 FILE *infile;
  51                 char buffer[1024];
  52                 int n;
  53
  54                 infile = tmpfile();
  55                 if (infile == NULL) {
  56                         perror("tmpfile");
  57                         return NULL;
  58                 }
  59                 fd = dup(fileno(infile));
  60                 fclose(infile);
  61                 if (fd < 0)
  62                         return NULL;
  63
  64                 n = read(STDIN_FILENO, buffer, sizeof(buffer));
  65                 while (n > 0) {
  66                         if (write(fd, buffer, n) != n)
  67                                 goto failed;
  68                         n = read(STDIN_FILENO, buffer, sizeof(buffer));
  69                 }
  70         }
  71
  72         if (fstat(fd, &st))
  73                 goto failed;
  74
  75         *size = st.st_size;
  76         map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
  77
  78 failed:
  79         close(fd);
  80         if (map == MAP_FAILED)
  81                 return NULL;
  82         return map;
  83 }
  84
  85 /**
  86   * Return a copy of the next line in a mmap'ed file.
  87   * spaces in the beginning of the line is trimmed away.
  88   * Return a pointer to a static buffer.
  89   **/
  90 static void release_file(void *file, unsigned long size)
  91 {
  92         munmap(file, size);
  93 }
  94
  95
  96 static void *get_sym_value(struct elf_info *info, const Elf_Sym *sym)
  97 {
  98         return RTE_PTR_ADD(info->hdr,
  99                 info->sechdrs[sym->st_shndx].sh_offset + sym->st_value);
 100 }
 101
 102 static Elf_Sym *find_sym_in_symtab(struct elf_info *info,
 103                                    const char *name, Elf_Sym *last)
 104 {
 105         Elf_Sym *idx;
 106         if (last)
 107                 idx = last+1;
 108         else
 109                 idx = info->symtab_start;
 110
 111         for (; idx < info->symtab_stop; idx++) {
 112                 const char *n = sym_name(info, idx);
 113                 if (!strncmp(n, name, strlen(name)))
 114                         return idx;
 115         }
 116         return NULL;
 117 }
 118
 119 static int parse_elf(struct elf_info *info, const char *filename)
 120 {
 121         unsigned int i;
 122         Elf_Ehdr *hdr;
 123         Elf_Shdr *sechdrs;
 124         Elf_Sym  *sym;
 125         int endian;
 126         unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
 127
 128         hdr = grab_file(filename, &info->size);
 129         if (!hdr) {
 130                 perror(filename);
 131                 exit(1);
 132         }
 133         info->hdr = hdr;
 134         if (info->size < sizeof(*hdr)) {
 135                 /* file too small, assume this is an empty .o file */
 136                 return 0;
 137         }
 138         /* Is this a valid ELF file? */
 139         if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
 140             (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
 141             (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
 142             (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
 143                 /* Not an ELF file - silently ignore it */
 144                 return 0;
 145         }
 146
 147         if (!hdr->e_ident[EI_DATA]) {
 148                 /* Unknown endian */
 149                 return 0;
 150         }
 151
 152         endian = hdr->e_ident[EI_DATA];
 153
 154         /* Fix endianness in ELF header */
 155         hdr->e_type      = TO_NATIVE(endian, 16, hdr->e_type);
 156         hdr->e_machine   = TO_NATIVE(endian, 16, hdr->e_machine);
 157         hdr->e_version   = TO_NATIVE(endian, 32, hdr->e_version);
 158         hdr->e_entry     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_entry);
 159         hdr->e_phoff     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_phoff);
 160         hdr->e_shoff     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_shoff);
 161         hdr->e_flags     = TO_NATIVE(endian, 32, hdr->e_flags);
 162         hdr->e_ehsize    = TO_NATIVE(endian, 16, hdr->e_ehsize);
 163         hdr->e_phentsize = TO_NATIVE(endian, 16, hdr->e_phentsize);
 164         hdr->e_phnum     = TO_NATIVE(endian, 16, hdr->e_phnum);
 165         hdr->e_shentsize = TO_NATIVE(endian, 16, hdr->e_shentsize);
 166         hdr->e_shnum     = TO_NATIVE(endian, 16, hdr->e_shnum);
 167         hdr->e_shstrndx  = TO_NATIVE(endian, 16, hdr->e_shstrndx);
 168
 169         sechdrs = RTE_PTR_ADD(hdr, hdr->e_shoff);
 170         info->sechdrs = sechdrs;
 171
 172         /* Check if file offset is correct */
 173         if (hdr->e_shoff > info->size) {
 174                 fprintf(stderr, "section header offset=%lu in file '%s' "
 175                       "is bigger than filesize=%lu\n",
 176                       (unsigned long)hdr->e_shoff,
 177                       filename, info->size);
 178                 return 0;
 179         }
 180
 181         if (hdr->e_shnum == SHN_UNDEF) {
 182                 /*
 183                  * There are more than 64k sections,
 184                  * read count from .sh_size.
 185                  */
 186                 info->num_sections =
 187                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[0].sh_size);
 188         } else {
 189                 info->num_sections = hdr->e_shnum;
 190         }
 191         if (hdr->e_shstrndx == SHN_XINDEX)
 192                 info->secindex_strings =
 193                         TO_NATIVE(endian, 32, sechdrs[0].sh_link);
 194         else
 195                 info->secindex_strings = hdr->e_shstrndx;
 196
 197         /* Fix endianness in section headers */
 198         for (i = 0; i < info->num_sections; i++) {
 199                 sechdrs[i].sh_name      =
 200                         TO_NATIVE(endian, 32, sechdrs[i].sh_name);
 201                 sechdrs[i].sh_type      =
 202                         TO_NATIVE(endian, 32, sechdrs[i].sh_type);
 203                 sechdrs[i].sh_flags     =
 204                         TO_NATIVE(endian, 32, sechdrs[i].sh_flags);
 205                 sechdrs[i].sh_addr      =
 206                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_addr);
 207                 sechdrs[i].sh_offset    =
 208                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_offset);
 209                 sechdrs[i].sh_size      =
 210                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_size);
 211                 sechdrs[i].sh_link      =
 212                         TO_NATIVE(endian, 32, sechdrs[i].sh_link);
 213                 sechdrs[i].sh_info      =
 214                         TO_NATIVE(endian, 32, sechdrs[i].sh_info);
 215                 sechdrs[i].sh_addralign =
 216                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_addralign);
 217                 sechdrs[i].sh_entsize   =
 218                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_entsize);
 219         }
 220         /* Find symbol table. */
 221         for (i = 1; i < info->num_sections; i++) {
 222                 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
 223
 224                 if (!nobits && sechdrs[i].sh_offset > info->size) {
 225                         fprintf(stderr, "%s is truncated. "
 226                               "sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n",
 227                               filename, (unsigned long)sechdrs[i].sh_offset,
 228                               sizeof(*hdr));
 229                         return 0;
 230                 }
 231
 232                 if (sechdrs[i].sh_type == SHT_SYMTAB) {
 233                         unsigned int sh_link_idx;
 234                         symtab_idx = i;
 235                         info->symtab_start = RTE_PTR_ADD(hdr,
 236                                 sechdrs[i].sh_offset);
 237                         info->symtab_stop  = RTE_PTR_ADD(hdr,
 238                                 sechdrs[i].sh_offset + sechdrs[i].sh_size);
 239                         sh_link_idx = sechdrs[i].sh_link;
 240                         info->strtab       = RTE_PTR_ADD(hdr,
 241                                 sechdrs[sh_link_idx].sh_offset);
 242                 }
 243
 244                 /* 32bit section no. table? ("more than 64k sections") */
 245                 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
 246                         symtab_shndx_idx = i;
 247                         info->symtab_shndx_start = RTE_PTR_ADD(hdr,
 248                                 sechdrs[i].sh_offset);
 249                         info->symtab_shndx_stop  = RTE_PTR_ADD(hdr,
 250                                 sechdrs[i].sh_offset + sechdrs[i].sh_size);
 251                 }
 252         }
 253         if (!info->symtab_start)
 254                 fprintf(stderr, "%s has no symtab?\n", filename);
 255         else {
 256                 /* Fix endianness in symbols */
 257                 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
 258                         sym->st_shndx = TO_NATIVE(endian, 16, sym->st_shndx);
 259                         sym->st_name  = TO_NATIVE(endian, 32, sym->st_name);
 260                         sym->st_value = TO_NATIVE(endian, ADDR_SIZE, sym->st_value);
 261                         sym->st_size  = TO_NATIVE(endian, ADDR_SIZE, sym->st_size);
 262                 }
 263         }
 264
 265         if (symtab_shndx_idx != ~0U) {
 266                 Elf32_Word *p;
 267                 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
 268                         fprintf(stderr,
 269                               "%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
 270                               filename, sechdrs[symtab_shndx_idx].sh_link,
 271                               symtab_idx);
 272                 /* Fix endianness */
 273                 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
 274                      p++)
 275                         *p = TO_NATIVE(endian, 32, *p);
 276         }
 277
 278         return 1;
 279 }
 280
 281 static void parse_elf_finish(struct elf_info *info)
 282 {
 283         struct pmd_driver *tmp, *idx = info->drivers;
 284         release_file(info->hdr, info->size);
 285         while (idx) {
 286                 tmp = idx->next;
 287                 free(idx);
 288                 idx = tmp;
 289         }
 290 }
 291
 292 struct opt_tag {
 293         const char *suffix;
 294         const char *json_id;
 295 };
 296
 297 static const struct opt_tag opt_tags[] = {
 298         {"_param_string_export", "params"},
 299         {"_kmod_dep_export", "kmod"},
 300 };
 301
 302 static int complete_pmd_entry(struct elf_info *info, struct pmd_driver *drv)
 303 {
 304         const char *tname;
 305         int i;
 306         char tmpsymname[128];
 307         Elf_Sym *tmpsym;
 308
 309         drv->name = get_sym_value(info, drv->name_sym);
 310
 311         for (i = 0; i < PMD_OPT_MAX; i++) {
 312                 memset(tmpsymname, 0, 128);
 313                 sprintf(tmpsymname, "__%s%s", drv->name, opt_tags[i].suffix);
 314                 tmpsym = find_sym_in_symtab(info, tmpsymname, NULL);
 315                 if (!tmpsym)
 316                         continue;
 317                 drv->opt_vals[i] = get_sym_value(info, tmpsym);
 318         }
 319
 320         memset(tmpsymname, 0, 128);
 321         sprintf(tmpsymname, "__%s_pci_tbl_export", drv->name);
 322
 323         tmpsym = find_sym_in_symtab(info, tmpsymname, NULL);
 324
 325
 326         /*
 327          * If this returns NULL, then this is a PMD_VDEV, because
 328          * it has no pci table reference
 329          */
 330         if (!tmpsym) {
 331                 drv->pci_tbl = NULL;
 332                 return 0;
 333         }
 334
 335         tname = get_sym_value(info, tmpsym);
 336         tmpsym = find_sym_in_symtab(info, tname, NULL);
 337         if (!tmpsym)
 338                 return -ENOENT;
 339
 340         drv->pci_tbl = (struct rte_pci_id *)get_sym_value(info, tmpsym);
 341         if (!drv->pci_tbl)
 342                 return -ENOENT;
 343
 344         return 0;
 345 }
 346
 347 static int locate_pmd_entries(struct elf_info *info)
 348 {
 349         Elf_Sym *last = NULL;
 350         struct pmd_driver *new;
 351
 352         info->drivers = NULL;
 353
 354         do {
 355                 new = calloc(sizeof(struct pmd_driver), 1);
 356                 if (new == NULL) {
 357                         fprintf(stderr, "Failed to calloc memory\n");
 358                         return -1;
 359                 }
 360                 new->name_sym = find_sym_in_symtab(info, "this_pmd_name", last);
 361                 last = new->name_sym;
 362                 if (!new->name_sym)
 363                         free(new);
 364                 else {
 365                         if (complete_pmd_entry(info, new)) {
 366                                 fprintf(stderr,
 367                                         "Failed to complete pmd entry\n");
 368                                 free(new);
 369                         } else {
 370                                 new->next = info->drivers;
 371                                 info->drivers = new;
 372                         }
 373                 }
 374         } while (last);
 375
 376         return 0;
 377 }
 378
 379 static void output_pmd_info_string(struct elf_info *info, char *outfile)
 380 {
 381         FILE *ofd;
 382         struct pmd_driver *drv;
 383         struct rte_pci_id *pci_ids;
 384         int idx = 0;
 385
 386         if (use_stdout)
 387                 ofd = stdout;
 388         else {
 389                 ofd = fopen(outfile, "w+");
 390                 if (!ofd) {
 391                         fprintf(stderr, "Unable to open output file\n");
 392                         return;
 393                 }
 394         }
 395
 396         drv = info->drivers;
 397
 398         while (drv) {
 399                 fprintf(ofd, "const char %s_pmd_info[] __attribute__((used)) = "
 400                         "\"PMD_INFO_STRING= {",
 401                         drv->name);
 402                 fprintf(ofd, "\\\"name\\\" : \\\"%s\\\", ", drv->name);
 403
 404                 for (idx = 0; idx < PMD_OPT_MAX; idx++) {
 405                         if (drv->opt_vals[idx])
 406                                 fprintf(ofd, "\\\"%s\\\" : \\\"%s\\\", ",
 407                                         opt_tags[idx].json_id,
 408                                         drv->opt_vals[idx]);
 409                 }
 410
 411                 pci_ids = drv->pci_tbl;
 412                 fprintf(ofd, "\\\"pci_ids\\\" : [");
 413
 414                 while (pci_ids && pci_ids->device_id) {
 415                         fprintf(ofd, "[%d, %d, %d, %d]",
 416                                 pci_ids->vendor_id, pci_ids->device_id,
 417                                 pci_ids->subsystem_vendor_id,
 418                                 pci_ids->subsystem_device_id);
 419                         pci_ids++;
 420                         if (pci_ids->device_id)
 421                                 fprintf(ofd, ",");
 422                         else
 423                                 fprintf(ofd, " ");
 424                 }
 425                 fprintf(ofd, "]}\";\n");
 426                 drv = drv->next;
 427         }
 428
 429         fclose(ofd);
 430 }
 431
 432 int main(int argc, char **argv)
 433 {
 434         struct elf_info info = {0};
 435         int rc = 1;
 436
 437         if (argc < 3) {
 438                 fprintf(stderr,
 439                         "usage: %s <object file> <c output file>\n",
 440                         basename(argv[0]));
 441                 exit(127);
 442         }
 443         use_stdin = !strcmp(argv[1], "-");
 444         use_stdout = !strcmp(argv[2], "-");
 445         parse_elf(&info, argv[1]);
 446
 447         if (locate_pmd_entries(&info) < 0)
 448                 exit(1);
 449
 450         if (info.drivers) {
 451                 output_pmd_info_string(&info, argv[2]);
 452                 rc = 0;
 453         } else {
 454                 fprintf(stderr, "No drivers registered\n");
 455         }
 456
 457         parse_elf_finish(&info);
 458         exit(rc);
 459 }