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 <libgen.h>
  19
  20 #include <rte_common.h>
  21 #include "pmdinfogen.h"
  22
  23 #ifdef RTE_ARCH_64
  24 #define ADDR_SIZE 64
  25 #else
  26 #define ADDR_SIZE 32
  27 #endif
  28
  29 static int use_stdin, use_stdout;
  30
  31 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
  32 {
  33         if (sym)
  34                 return elf->strtab + sym->st_name;
  35         else
  36                 return "(unknown)";
  37 }
  38
  39 static void *grab_file(const char *filename, unsigned long *size)
  40 {
  41         struct stat st;
  42         void *map = MAP_FAILED;
  43         int fd = -1;
  44
  45         if (!use_stdin) {
  46                 fd = open(filename, O_RDONLY);
  47                 if (fd < 0)
  48                         return NULL;
  49         } else {
  50                 /* from stdin, use a temporary file to mmap */
  51                 FILE *infile;
  52                 char buffer[1024];
  53                 int n;
  54
  55                 infile = tmpfile();
  56                 if (infile == NULL) {
  57                         perror("tmpfile");
  58                         return NULL;
  59                 }
  60                 fd = dup(fileno(infile));
  61                 fclose(infile);
  62                 if (fd < 0)
  63                         return NULL;
  64
  65                 n = read(STDIN_FILENO, buffer, sizeof(buffer));
  66                 while (n > 0) {
  67                         if (write(fd, buffer, n) != n)
  68                                 goto failed;
  69                         n = read(STDIN_FILENO, buffer, sizeof(buffer));
  70                 }
  71         }
  72
  73         if (fstat(fd, &st))
  74                 goto failed;
  75
  76         *size = st.st_size;
  77         map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
  78
  79 failed:
  80         close(fd);
  81         if (map == MAP_FAILED)
  82                 return NULL;
  83         return map;
  84 }
  85
  86 /**
  87   * Return a copy of the next line in a mmap'ed file.
  88   * spaces in the beginning of the line is trimmed away.
  89   * Return a pointer to a static buffer.
  90   **/
  91 static void release_file(void *file, unsigned long size)
  92 {
  93         munmap(file, size);
  94 }
  95
  96
  97 static void *get_sym_value(struct elf_info *info, const Elf_Sym *sym)
  98 {
  99         return RTE_PTR_ADD(info->hdr,
 100                 info->sechdrs[sym->st_shndx].sh_offset + sym->st_value);
 101 }
 102
 103 static Elf_Sym *find_sym_in_symtab(struct elf_info *info,
 104                                    const char *name, Elf_Sym *last)
 105 {
 106         Elf_Sym *idx;
 107         if (last)
 108                 idx = last+1;
 109         else
 110                 idx = info->symtab_start;
 111
 112         for (; idx < info->symtab_stop; idx++) {
 113                 const char *n = sym_name(info, idx);
 114                 if (!strncmp(n, name, strlen(name)))
 115                         return idx;
 116         }
 117         return NULL;
 118 }
 119
 120 static int parse_elf(struct elf_info *info, const char *filename)
 121 {
 122         unsigned int i;
 123         Elf_Ehdr *hdr;
 124         Elf_Shdr *sechdrs;
 125         Elf_Sym  *sym;
 126         int endian;
 127         unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
 128
 129         hdr = grab_file(filename, &info->size);
 130         if (!hdr) {
 131                 perror(filename);
 132                 exit(1);
 133         }
 134         info->hdr = hdr;
 135         if (info->size < sizeof(*hdr)) {
 136                 /* file too small, assume this is an empty .o file */
 137                 return 0;
 138         }
 139         /* Is this a valid ELF file? */
 140         if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
 141             (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
 142             (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
 143             (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
 144                 /* Not an ELF file - silently ignore it */
 145                 return 0;
 146         }
 147
 148         if (!hdr->e_ident[EI_DATA]) {
 149                 /* Unknown endian */
 150                 return 0;
 151         }
 152
 153         endian = hdr->e_ident[EI_DATA];
 154
 155         /* Fix endianness in ELF header */
 156         hdr->e_type      = TO_NATIVE(endian, 16, hdr->e_type);
 157         hdr->e_machine   = TO_NATIVE(endian, 16, hdr->e_machine);
 158         hdr->e_version   = TO_NATIVE(endian, 32, hdr->e_version);
 159         hdr->e_entry     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_entry);
 160         hdr->e_phoff     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_phoff);
 161         hdr->e_shoff     = TO_NATIVE(endian, ADDR_SIZE, hdr->e_shoff);
 162         hdr->e_flags     = TO_NATIVE(endian, 32, hdr->e_flags);
 163         hdr->e_ehsize    = TO_NATIVE(endian, 16, hdr->e_ehsize);
 164         hdr->e_phentsize = TO_NATIVE(endian, 16, hdr->e_phentsize);
 165         hdr->e_phnum     = TO_NATIVE(endian, 16, hdr->e_phnum);
 166         hdr->e_shentsize = TO_NATIVE(endian, 16, hdr->e_shentsize);
 167         hdr->e_shnum     = TO_NATIVE(endian, 16, hdr->e_shnum);
 168         hdr->e_shstrndx  = TO_NATIVE(endian, 16, hdr->e_shstrndx);
 169
 170         sechdrs = RTE_PTR_ADD(hdr, hdr->e_shoff);
 171         info->sechdrs = sechdrs;
 172
 173         /* Check if file offset is correct */
 174         if (hdr->e_shoff > info->size) {
 175                 fprintf(stderr, "section header offset=%lu in file '%s' "
 176                       "is bigger than filesize=%lu\n",
 177                       (unsigned long)hdr->e_shoff,
 178                       filename, info->size);
 179                 return 0;
 180         }
 181
 182         if (hdr->e_shnum == SHN_UNDEF) {
 183                 /*
 184                  * There are more than 64k sections,
 185                  * read count from .sh_size.
 186                  */
 187                 info->num_sections =
 188                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[0].sh_size);
 189         } else {
 190                 info->num_sections = hdr->e_shnum;
 191         }
 192         if (hdr->e_shstrndx == SHN_XINDEX)
 193                 info->secindex_strings =
 194                         TO_NATIVE(endian, 32, sechdrs[0].sh_link);
 195         else
 196                 info->secindex_strings = hdr->e_shstrndx;
 197
 198         /* Fix endianness in section headers */
 199         for (i = 0; i < info->num_sections; i++) {
 200                 sechdrs[i].sh_name      =
 201                         TO_NATIVE(endian, 32, sechdrs[i].sh_name);
 202                 sechdrs[i].sh_type      =
 203                         TO_NATIVE(endian, 32, sechdrs[i].sh_type);
 204                 sechdrs[i].sh_flags     =
 205                         TO_NATIVE(endian, 32, sechdrs[i].sh_flags);
 206                 sechdrs[i].sh_addr      =
 207                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_addr);
 208                 sechdrs[i].sh_offset    =
 209                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_offset);
 210                 sechdrs[i].sh_size      =
 211                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_size);
 212                 sechdrs[i].sh_link      =
 213                         TO_NATIVE(endian, 32, sechdrs[i].sh_link);
 214                 sechdrs[i].sh_info      =
 215                         TO_NATIVE(endian, 32, sechdrs[i].sh_info);
 216                 sechdrs[i].sh_addralign =
 217                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_addralign);
 218                 sechdrs[i].sh_entsize   =
 219                         TO_NATIVE(endian, ADDR_SIZE, sechdrs[i].sh_entsize);
 220         }
 221         /* Find symbol table. */
 222         for (i = 1; i < info->num_sections; i++) {
 223                 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
 224
 225                 if (!nobits && sechdrs[i].sh_offset > info->size) {
 226                         fprintf(stderr, "%s is truncated. "
 227                               "sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n",
 228                               filename, (unsigned long)sechdrs[i].sh_offset,
 229                               sizeof(*hdr));
 230                         return 0;
 231                 }
 232
 233                 if (sechdrs[i].sh_type == SHT_SYMTAB) {
 234                         unsigned int sh_link_idx;
 235                         symtab_idx = i;
 236                         info->symtab_start = RTE_PTR_ADD(hdr,
 237                                 sechdrs[i].sh_offset);
 238                         info->symtab_stop  = RTE_PTR_ADD(hdr,
 239                                 sechdrs[i].sh_offset + sechdrs[i].sh_size);
 240                         sh_link_idx = sechdrs[i].sh_link;
 241                         info->strtab       = RTE_PTR_ADD(hdr,
 242                                 sechdrs[sh_link_idx].sh_offset);
 243                 }
 244
 245                 /* 32bit section no. table? ("more than 64k sections") */
 246                 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
 247                         symtab_shndx_idx = i;
 248                         info->symtab_shndx_start = RTE_PTR_ADD(hdr,
 249                                 sechdrs[i].sh_offset);
 250                         info->symtab_shndx_stop  = RTE_PTR_ADD(hdr,
 251                                 sechdrs[i].sh_offset + sechdrs[i].sh_size);
 252                 }
 253         }
 254         if (!info->symtab_start)
 255                 fprintf(stderr, "%s has no symtab?\n", filename);
 256         else {
 257                 /* Fix endianness in symbols */
 258                 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
 259                         sym->st_shndx = TO_NATIVE(endian, 16, sym->st_shndx);
 260                         sym->st_name  = TO_NATIVE(endian, 32, sym->st_name);
 261                         sym->st_value = TO_NATIVE(endian, ADDR_SIZE, sym->st_value);
 262                         sym->st_size  = TO_NATIVE(endian, ADDR_SIZE, sym->st_size);
 263                 }
 264         }
 265
 266         if (symtab_shndx_idx != ~0U) {
 267                 Elf32_Word *p;
 268                 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
 269                         fprintf(stderr,
 270                               "%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
 271                               filename, sechdrs[symtab_shndx_idx].sh_link,
 272                               symtab_idx);
 273                 /* Fix endianness */
 274                 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
 275                      p++)
 276                         *p = TO_NATIVE(endian, 32, *p);
 277         }
 278
 279         return 1;
 280 }
 281
 282 static void parse_elf_finish(struct elf_info *info)
 283 {
 284         struct pmd_driver *tmp, *idx = info->drivers;
 285         release_file(info->hdr, info->size);
 286         while (idx) {
 287                 tmp = idx->next;
 288                 free(idx);
 289                 idx = tmp;
 290         }
 291 }
 292
 293 struct opt_tag {
 294         const char *suffix;
 295         const char *json_id;
 296 };
 297
 298 static const struct opt_tag opt_tags[] = {
 299         {"_param_string_export", "params"},
 300         {"_kmod_dep_export", "kmod"},
 301 };
 302
 303 static int complete_pmd_entry(struct elf_info *info, struct pmd_driver *drv)
 304 {
 305         const char *tname;
 306         int i;
 307         char tmpsymname[128];
 308         Elf_Sym *tmpsym;
 309
 310         drv->name = get_sym_value(info, drv->name_sym);
 311
 312         for (i = 0; i < PMD_OPT_MAX; i++) {
 313                 memset(tmpsymname, 0, 128);
 314                 sprintf(tmpsymname, "__%s%s", drv->name, opt_tags[i].suffix);
 315                 tmpsym = find_sym_in_symtab(info, tmpsymname, NULL);
 316                 if (!tmpsym)
 317                         continue;
 318                 drv->opt_vals[i] = get_sym_value(info, tmpsym);
 319         }
 320
 321         memset(tmpsymname, 0, 128);
 322         sprintf(tmpsymname, "__%s_pci_tbl_export", drv->name);
 323
 324         tmpsym = find_sym_in_symtab(info, tmpsymname, NULL);
 325
 326
 327         /*
 328          * If this returns NULL, then this is a PMD_VDEV, because
 329          * it has no pci table reference
 330          */
 331         if (!tmpsym) {
 332                 drv->pci_tbl = NULL;
 333                 return 0;
 334         }
 335
 336         tname = get_sym_value(info, tmpsym);
 337         tmpsym = find_sym_in_symtab(info, tname, NULL);
 338         if (!tmpsym)
 339                 return -ENOENT;
 340
 341         drv->pci_tbl = (struct rte_pci_id *)get_sym_value(info, tmpsym);
 342         if (!drv->pci_tbl)
 343                 return -ENOENT;
 344
 345         return 0;
 346 }
 347
 348 static int locate_pmd_entries(struct elf_info *info)
 349 {
 350         Elf_Sym *last = NULL;
 351         struct pmd_driver *new;
 352
 353         info->drivers = NULL;
 354
 355         do {
 356                 new = calloc(sizeof(struct pmd_driver), 1);
 357                 if (new == NULL) {
 358                         fprintf(stderr, "Failed to calloc memory\n");
 359                         return -1;
 360                 }
 361                 new->name_sym = find_sym_in_symtab(info, "this_pmd_name", last);
 362                 last = new->name_sym;
 363                 if (!new->name_sym)
 364                         free(new);
 365                 else {
 366                         if (complete_pmd_entry(info, new)) {
 367                                 fprintf(stderr,
 368                                         "Failed to complete pmd entry\n");
 369                                 free(new);
 370                         } else {
 371                                 new->next = info->drivers;
 372                                 info->drivers = new;
 373                         }
 374                 }
 375         } while (last);
 376
 377         return 0;
 378 }
 379
 380 static void output_pmd_info_string(struct elf_info *info, char *outfile)
 381 {
 382         FILE *ofd;
 383         struct pmd_driver *drv;
 384         struct rte_pci_id *pci_ids;
 385         int idx = 0;
 386
 387         if (use_stdout)
 388                 ofd = stdout;
 389         else {
 390                 ofd = fopen(outfile, "w+");
 391                 if (!ofd) {
 392                         fprintf(stderr, "Unable to open output file\n");
 393                         return;
 394                 }
 395         }
 396
 397         drv = info->drivers;
 398
 399         while (drv) {
 400                 fprintf(ofd, "const char %s_pmd_info[] __attribute__((used)) = "
 401                         "\"PMD_INFO_STRING= {",
 402                         drv->name);
 403                 fprintf(ofd, "\\\"name\\\" : \\\"%s\\\", ", drv->name);
 404
 405                 for (idx = 0; idx < PMD_OPT_MAX; idx++) {
 406                         if (drv->opt_vals[idx])
 407                                 fprintf(ofd, "\\\"%s\\\" : \\\"%s\\\", ",
 408                                         opt_tags[idx].json_id,
 409                                         drv->opt_vals[idx]);
 410                 }
 411
 412                 pci_ids = drv->pci_tbl;
 413                 fprintf(ofd, "\\\"pci_ids\\\" : [");
 414
 415                 while (pci_ids && pci_ids->device_id) {
 416                         fprintf(ofd, "[%d, %d, %d, %d]",
 417                                 pci_ids->vendor_id, pci_ids->device_id,
 418                                 pci_ids->subsystem_vendor_id,
 419                                 pci_ids->subsystem_device_id);
 420                         pci_ids++;
 421                         if (pci_ids->device_id)
 422                                 fprintf(ofd, ",");
 423                         else
 424                                 fprintf(ofd, " ");
 425                 }
 426                 fprintf(ofd, "]}\";\n");
 427                 drv = drv->next;
 428         }
 429
 430         fclose(ofd);
 431 }
 432
 433 int main(int argc, char **argv)
 434 {
 435         struct elf_info info = {0};
 436         int rc = 1;
 437
 438         if (argc < 3) {
 439                 fprintf(stderr,
 440                         "usage: %s <object file> <c output file>\n",
 441                         basename(argv[0]));
 442                 exit(127);
 443         }
 444         use_stdin = !strcmp(argv[1], "-");
 445         use_stdout = !strcmp(argv[2], "-");
 446         parse_elf(&info, argv[1]);
 447
 448         if (locate_pmd_entries(&info) < 0)
 449                 exit(1);
 450
 451         if (info.drivers) {
 452                 output_pmd_info_string(&info, argv[2]);
 453                 rc = 0;
 454         } else {
 455                 fprintf(stderr, "No drivers registered\n");
 456         }
 457
 458         parse_elf_finish(&info);
 459         exit(rc);
 460 }