1 /* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 2004, 2005 MIPS Technologies, Inc. All rights reserved. 7 * Copyright (C) 2013 Imagination Technologies Ltd. 8 * 9 * VPE spport module for loading a MIPS SP program into VPE1. The SP 10 * environment is rather simple since there are no TLBs. It needs 11 * to be relocatable (or partiall linked). Initialize your stack in 12 * the startup-code. The loader looks for the symbol __start and sets 13 * up the execution to resume from there. To load and run, simply do 14 * a cat SP 'binary' to the /dev/vpe1 device. 15 */ 16 #include <linux/kernel.h> 17 #include <linux/device.h> 18 #include <linux/fs.h> 19 #include <linux/init.h> 20 #include <linux/slab.h> 21 #include <linux/list.h> 22 #include <linux/vmalloc.h> 23 #include <linux/elf.h> 24 #include <linux/seq_file.h> 25 #include <linux/syscalls.h> 26 #include <linux/moduleloader.h> 27 #include <linux/interrupt.h> 28 #include <linux/poll.h> 29 #include <linux/bootmem.h> 30 #include <asm/mipsregs.h> 31 #include <asm/mipsmtregs.h> 32 #include <asm/cacheflush.h> 33 #include <linux/atomic.h> 34 #include <asm/mips_mt.h> 35 #include <asm/processor.h> 36 #include <asm/vpe.h> 37 38 #ifndef ARCH_SHF_SMALL 39 #define ARCH_SHF_SMALL 0 40 #endif 41 42 /* If this is set, the section belongs in the init part of the module */ 43 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) 44 45 struct vpe_control vpecontrol = { 46 .vpe_list_lock = __SPIN_LOCK_UNLOCKED(vpe_list_lock), 47 .vpe_list = LIST_HEAD_INIT(vpecontrol.vpe_list), 48 .tc_list_lock = __SPIN_LOCK_UNLOCKED(tc_list_lock), 49 .tc_list = LIST_HEAD_INIT(vpecontrol.tc_list) 50 }; 51 52 /* get the vpe associated with this minor */ 53 struct vpe *get_vpe(int minor) 54 { 55 struct vpe *res, *v; 56 57 if (!cpu_has_mipsmt) 58 return NULL; 59 60 res = NULL; 61 spin_lock(&vpecontrol.vpe_list_lock); 62 list_for_each_entry(v, &vpecontrol.vpe_list, list) { 63 if (v->minor == VPE_MODULE_MINOR) { 64 res = v; 65 break; 66 } 67 } 68 spin_unlock(&vpecontrol.vpe_list_lock); 69 70 return res; 71 } 72 73 /* get the vpe associated with this minor */ 74 struct tc *get_tc(int index) 75 { 76 struct tc *res, *t; 77 78 res = NULL; 79 spin_lock(&vpecontrol.tc_list_lock); 80 list_for_each_entry(t, &vpecontrol.tc_list, list) { 81 if (t->index == index) { 82 res = t; 83 break; 84 } 85 } 86 spin_unlock(&vpecontrol.tc_list_lock); 87 88 return res; 89 } 90 91 /* allocate a vpe and associate it with this minor (or index) */ 92 struct vpe *alloc_vpe(int minor) 93 { 94 struct vpe *v; 95 96 v = kzalloc(sizeof(struct vpe), GFP_KERNEL); 97 if (v == NULL) 98 goto out; 99 100 INIT_LIST_HEAD(&v->tc); 101 spin_lock(&vpecontrol.vpe_list_lock); 102 list_add_tail(&v->list, &vpecontrol.vpe_list); 103 spin_unlock(&vpecontrol.vpe_list_lock); 104 105 INIT_LIST_HEAD(&v->notify); 106 v->minor = VPE_MODULE_MINOR; 107 108 out: 109 return v; 110 } 111 112 /* allocate a tc. At startup only tc0 is running, all other can be halted. */ 113 struct tc *alloc_tc(int index) 114 { 115 struct tc *tc; 116 117 tc = kzalloc(sizeof(struct tc), GFP_KERNEL); 118 if (tc == NULL) 119 goto out; 120 121 INIT_LIST_HEAD(&tc->tc); 122 tc->index = index; 123 124 spin_lock(&vpecontrol.tc_list_lock); 125 list_add_tail(&tc->list, &vpecontrol.tc_list); 126 spin_unlock(&vpecontrol.tc_list_lock); 127 128 out: 129 return tc; 130 } 131 132 /* clean up and free everything */ 133 void release_vpe(struct vpe *v) 134 { 135 list_del(&v->list); 136 if (v->load_addr) 137 release_progmem(v); 138 kfree(v); 139 } 140 141 /* Find some VPE program space */ 142 void *alloc_progmem(unsigned long len) 143 { 144 void *addr; 145 146 #ifdef CONFIG_MIPS_VPE_LOADER_TOM 147 /* 148 * This means you must tell Linux to use less memory than you 149 * physically have, for example by passing a mem= boot argument. 150 */ 151 addr = pfn_to_kaddr(max_low_pfn); 152 memset(addr, 0, len); 153 #else 154 /* simple grab some mem for now */ 155 addr = kzalloc(len, GFP_KERNEL); 156 #endif 157 158 return addr; 159 } 160 161 void release_progmem(void *ptr) 162 { 163 #ifndef CONFIG_MIPS_VPE_LOADER_TOM 164 kfree(ptr); 165 #endif 166 } 167 168 /* Update size with this section: return offset. */ 169 static long get_offset(unsigned long *size, Elf_Shdr *sechdr) 170 { 171 long ret; 172 173 ret = ALIGN(*size, sechdr->sh_addralign ? : 1); 174 *size = ret + sechdr->sh_size; 175 return ret; 176 } 177 178 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld 179 might -- code, read-only data, read-write data, small data. Tally 180 sizes, and place the offsets into sh_entsize fields: high bit means it 181 belongs in init. */ 182 static void layout_sections(struct module *mod, const Elf_Ehdr *hdr, 183 Elf_Shdr *sechdrs, const char *secstrings) 184 { 185 static unsigned long const masks[][2] = { 186 /* NOTE: all executable code must be the first section 187 * in this array; otherwise modify the text_size 188 * finder in the two loops below */ 189 {SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL}, 190 {SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL}, 191 {SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL}, 192 {ARCH_SHF_SMALL | SHF_ALLOC, 0} 193 }; 194 unsigned int m, i; 195 196 for (i = 0; i < hdr->e_shnum; i++) 197 sechdrs[i].sh_entsize = ~0UL; 198 199 for (m = 0; m < ARRAY_SIZE(masks); ++m) { 200 for (i = 0; i < hdr->e_shnum; ++i) { 201 Elf_Shdr *s = &sechdrs[i]; 202 203 if ((s->sh_flags & masks[m][0]) != masks[m][0] 204 || (s->sh_flags & masks[m][1]) 205 || s->sh_entsize != ~0UL) 206 continue; 207 s->sh_entsize = 208 get_offset((unsigned long *)&mod->core_layout.size, s); 209 } 210 211 if (m == 0) 212 mod->core_layout.text_size = mod->core_layout.size; 213 214 } 215 } 216 217 /* from module-elf32.c, but subverted a little */ 218 219 struct mips_hi16 { 220 struct mips_hi16 *next; 221 Elf32_Addr *addr; 222 Elf32_Addr value; 223 }; 224 225 static struct mips_hi16 *mips_hi16_list; 226 static unsigned int gp_offs, gp_addr; 227 228 static int apply_r_mips_none(struct module *me, uint32_t *location, 229 Elf32_Addr v) 230 { 231 return 0; 232 } 233 234 static int apply_r_mips_gprel16(struct module *me, uint32_t *location, 235 Elf32_Addr v) 236 { 237 int rel; 238 239 if (!(*location & 0xffff)) { 240 rel = (int)v - gp_addr; 241 } else { 242 /* .sbss + gp(relative) + offset */ 243 /* kludge! */ 244 rel = (int)(short)((int)v + gp_offs + 245 (int)(short)(*location & 0xffff) - gp_addr); 246 } 247 248 if ((rel > 32768) || (rel < -32768)) { 249 pr_debug("VPE loader: apply_r_mips_gprel16: relative address 0x%x out of range of gp register\n", 250 rel); 251 return -ENOEXEC; 252 } 253 254 *location = (*location & 0xffff0000) | (rel & 0xffff); 255 256 return 0; 257 } 258 259 static int apply_r_mips_pc16(struct module *me, uint32_t *location, 260 Elf32_Addr v) 261 { 262 int rel; 263 rel = (((unsigned int)v - (unsigned int)location)); 264 rel >>= 2; /* because the offset is in _instructions_ not bytes. */ 265 rel -= 1; /* and one instruction less due to the branch delay slot. */ 266 267 if ((rel > 32768) || (rel < -32768)) { 268 pr_debug("VPE loader: apply_r_mips_pc16: relative address out of range 0x%x\n", 269 rel); 270 return -ENOEXEC; 271 } 272 273 *location = (*location & 0xffff0000) | (rel & 0xffff); 274 275 return 0; 276 } 277 278 static int apply_r_mips_32(struct module *me, uint32_t *location, 279 Elf32_Addr v) 280 { 281 *location += v; 282 283 return 0; 284 } 285 286 static int apply_r_mips_26(struct module *me, uint32_t *location, 287 Elf32_Addr v) 288 { 289 if (v % 4) { 290 pr_debug("VPE loader: apply_r_mips_26: unaligned relocation\n"); 291 return -ENOEXEC; 292 } 293 294 /* 295 * Not desperately convinced this is a good check of an overflow condition 296 * anyway. But it gets in the way of handling undefined weak symbols which 297 * we want to set to zero. 298 * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) { 299 * printk(KERN_ERR 300 * "module %s: relocation overflow\n", 301 * me->name); 302 * return -ENOEXEC; 303 * } 304 */ 305 306 *location = (*location & ~0x03ffffff) | 307 ((*location + (v >> 2)) & 0x03ffffff); 308 return 0; 309 } 310 311 static int apply_r_mips_hi16(struct module *me, uint32_t *location, 312 Elf32_Addr v) 313 { 314 struct mips_hi16 *n; 315 316 /* 317 * We cannot relocate this one now because we don't know the value of 318 * the carry we need to add. Save the information, and let LO16 do the 319 * actual relocation. 320 */ 321 n = kmalloc(sizeof(*n), GFP_KERNEL); 322 if (!n) 323 return -ENOMEM; 324 325 n->addr = location; 326 n->value = v; 327 n->next = mips_hi16_list; 328 mips_hi16_list = n; 329 330 return 0; 331 } 332 333 static int apply_r_mips_lo16(struct module *me, uint32_t *location, 334 Elf32_Addr v) 335 { 336 unsigned long insnlo = *location; 337 Elf32_Addr val, vallo; 338 struct mips_hi16 *l, *next; 339 340 /* Sign extend the addend we extract from the lo insn. */ 341 vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000; 342 343 if (mips_hi16_list != NULL) { 344 345 l = mips_hi16_list; 346 while (l != NULL) { 347 unsigned long insn; 348 349 /* 350 * The value for the HI16 had best be the same. 351 */ 352 if (v != l->value) { 353 pr_debug("VPE loader: apply_r_mips_lo16/hi16: inconsistent value information\n"); 354 goto out_free; 355 } 356 357 /* 358 * Do the HI16 relocation. Note that we actually don't 359 * need to know anything about the LO16 itself, except 360 * where to find the low 16 bits of the addend needed 361 * by the LO16. 362 */ 363 insn = *l->addr; 364 val = ((insn & 0xffff) << 16) + vallo; 365 val += v; 366 367 /* 368 * Account for the sign extension that will happen in 369 * the low bits. 370 */ 371 val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff; 372 373 insn = (insn & ~0xffff) | val; 374 *l->addr = insn; 375 376 next = l->next; 377 kfree(l); 378 l = next; 379 } 380 381 mips_hi16_list = NULL; 382 } 383 384 /* 385 * Ok, we're done with the HI16 relocs. Now deal with the LO16. 386 */ 387 val = v + vallo; 388 insnlo = (insnlo & ~0xffff) | (val & 0xffff); 389 *location = insnlo; 390 391 return 0; 392 393 out_free: 394 while (l != NULL) { 395 next = l->next; 396 kfree(l); 397 l = next; 398 } 399 mips_hi16_list = NULL; 400 401 return -ENOEXEC; 402 } 403 404 static int (*reloc_handlers[]) (struct module *me, uint32_t *location, 405 Elf32_Addr v) = { 406 [R_MIPS_NONE] = apply_r_mips_none, 407 [R_MIPS_32] = apply_r_mips_32, 408 [R_MIPS_26] = apply_r_mips_26, 409 [R_MIPS_HI16] = apply_r_mips_hi16, 410 [R_MIPS_LO16] = apply_r_mips_lo16, 411 [R_MIPS_GPREL16] = apply_r_mips_gprel16, 412 [R_MIPS_PC16] = apply_r_mips_pc16 413 }; 414 415 static char *rstrs[] = { 416 [R_MIPS_NONE] = "MIPS_NONE", 417 [R_MIPS_32] = "MIPS_32", 418 [R_MIPS_26] = "MIPS_26", 419 [R_MIPS_HI16] = "MIPS_HI16", 420 [R_MIPS_LO16] = "MIPS_LO16", 421 [R_MIPS_GPREL16] = "MIPS_GPREL16", 422 [R_MIPS_PC16] = "MIPS_PC16" 423 }; 424 425 static int apply_relocations(Elf32_Shdr *sechdrs, 426 const char *strtab, 427 unsigned int symindex, 428 unsigned int relsec, 429 struct module *me) 430 { 431 Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr; 432 Elf32_Sym *sym; 433 uint32_t *location; 434 unsigned int i; 435 Elf32_Addr v; 436 int res; 437 438 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 439 Elf32_Word r_info = rel[i].r_info; 440 441 /* This is where to make the change */ 442 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr 443 + rel[i].r_offset; 444 /* This is the symbol it is referring to */ 445 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 446 + ELF32_R_SYM(r_info); 447 448 if (!sym->st_value) { 449 pr_debug("%s: undefined weak symbol %s\n", 450 me->name, strtab + sym->st_name); 451 /* just print the warning, dont barf */ 452 } 453 454 v = sym->st_value; 455 456 res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v); 457 if (res) { 458 char *r = rstrs[ELF32_R_TYPE(r_info)]; 459 pr_warn("VPE loader: .text+0x%x relocation type %s for symbol \"%s\" failed\n", 460 rel[i].r_offset, r ? r : "UNKNOWN", 461 strtab + sym->st_name); 462 return res; 463 } 464 } 465 466 return 0; 467 } 468 469 static inline void save_gp_address(unsigned int secbase, unsigned int rel) 470 { 471 gp_addr = secbase + rel; 472 gp_offs = gp_addr - (secbase & 0xffff0000); 473 } 474 /* end module-elf32.c */ 475 476 /* Change all symbols so that sh_value encodes the pointer directly. */ 477 static void simplify_symbols(Elf_Shdr *sechdrs, 478 unsigned int symindex, 479 const char *strtab, 480 const char *secstrings, 481 unsigned int nsecs, struct module *mod) 482 { 483 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr; 484 unsigned long secbase, bssbase = 0; 485 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym); 486 int size; 487 488 /* find the .bss section for COMMON symbols */ 489 for (i = 0; i < nsecs; i++) { 490 if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) { 491 bssbase = sechdrs[i].sh_addr; 492 break; 493 } 494 } 495 496 for (i = 1; i < n; i++) { 497 switch (sym[i].st_shndx) { 498 case SHN_COMMON: 499 /* Allocate space for the symbol in the .bss section. 500 st_value is currently size. 501 We want it to have the address of the symbol. */ 502 503 size = sym[i].st_value; 504 sym[i].st_value = bssbase; 505 506 bssbase += size; 507 break; 508 509 case SHN_ABS: 510 /* Don't need to do anything */ 511 break; 512 513 case SHN_UNDEF: 514 /* ret = -ENOENT; */ 515 break; 516 517 case SHN_MIPS_SCOMMON: 518 pr_debug("simplify_symbols: ignoring SHN_MIPS_SCOMMON symbol <%s> st_shndx %d\n", 519 strtab + sym[i].st_name, sym[i].st_shndx); 520 /* .sbss section */ 521 break; 522 523 default: 524 secbase = sechdrs[sym[i].st_shndx].sh_addr; 525 526 if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0) 527 save_gp_address(secbase, sym[i].st_value); 528 529 sym[i].st_value += secbase; 530 break; 531 } 532 } 533 } 534 535 #ifdef DEBUG_ELFLOADER 536 static void dump_elfsymbols(Elf_Shdr *sechdrs, unsigned int symindex, 537 const char *strtab, struct module *mod) 538 { 539 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr; 540 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym); 541 542 pr_debug("dump_elfsymbols: n %d\n", n); 543 for (i = 1; i < n; i++) { 544 pr_debug(" i %d name <%s> 0x%x\n", i, strtab + sym[i].st_name, 545 sym[i].st_value); 546 } 547 } 548 #endif 549 550 static int find_vpe_symbols(struct vpe *v, Elf_Shdr *sechdrs, 551 unsigned int symindex, const char *strtab, 552 struct module *mod) 553 { 554 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr; 555 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym); 556 557 for (i = 1; i < n; i++) { 558 if (strcmp(strtab + sym[i].st_name, "__start") == 0) 559 v->__start = sym[i].st_value; 560 561 if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0) 562 v->shared_ptr = (void *)sym[i].st_value; 563 } 564 565 if ((v->__start == 0) || (v->shared_ptr == NULL)) 566 return -1; 567 568 return 0; 569 } 570 571 /* 572 * Allocates a VPE with some program code space(the load address), copies the 573 * contents of the program (p)buffer performing relocatations/etc, free's it 574 * when finished. 575 */ 576 static int vpe_elfload(struct vpe *v) 577 { 578 Elf_Ehdr *hdr; 579 Elf_Shdr *sechdrs; 580 long err = 0; 581 char *secstrings, *strtab = NULL; 582 unsigned int len, i, symindex = 0, strindex = 0, relocate = 0; 583 struct module mod; /* so we can re-use the relocations code */ 584 585 memset(&mod, 0, sizeof(struct module)); 586 strcpy(mod.name, "VPE loader"); 587 588 hdr = (Elf_Ehdr *) v->pbuffer; 589 len = v->plen; 590 591 /* Sanity checks against insmoding binaries or wrong arch, 592 weird elf version */ 593 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0 594 || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC) 595 || !elf_check_arch(hdr) 596 || hdr->e_shentsize != sizeof(*sechdrs)) { 597 pr_warn("VPE loader: program wrong arch or weird elf version\n"); 598 599 return -ENOEXEC; 600 } 601 602 if (hdr->e_type == ET_REL) 603 relocate = 1; 604 605 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) { 606 pr_err("VPE loader: program length %u truncated\n", len); 607 608 return -ENOEXEC; 609 } 610 611 /* Convenience variables */ 612 sechdrs = (void *)hdr + hdr->e_shoff; 613 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; 614 sechdrs[0].sh_addr = 0; 615 616 /* And these should exist, but gcc whinges if we don't init them */ 617 symindex = strindex = 0; 618 619 if (relocate) { 620 for (i = 1; i < hdr->e_shnum; i++) { 621 if ((sechdrs[i].sh_type != SHT_NOBITS) && 622 (len < sechdrs[i].sh_offset + sechdrs[i].sh_size)) { 623 pr_err("VPE program length %u truncated\n", 624 len); 625 return -ENOEXEC; 626 } 627 628 /* Mark all sections sh_addr with their address in the 629 temporary image. */ 630 sechdrs[i].sh_addr = (size_t) hdr + 631 sechdrs[i].sh_offset; 632 633 /* Internal symbols and strings. */ 634 if (sechdrs[i].sh_type == SHT_SYMTAB) { 635 symindex = i; 636 strindex = sechdrs[i].sh_link; 637 strtab = (char *)hdr + 638 sechdrs[strindex].sh_offset; 639 } 640 } 641 layout_sections(&mod, hdr, sechdrs, secstrings); 642 } 643 644 v->load_addr = alloc_progmem(mod.core_layout.size); 645 if (!v->load_addr) 646 return -ENOMEM; 647 648 pr_info("VPE loader: loading to %p\n", v->load_addr); 649 650 if (relocate) { 651 for (i = 0; i < hdr->e_shnum; i++) { 652 void *dest; 653 654 if (!(sechdrs[i].sh_flags & SHF_ALLOC)) 655 continue; 656 657 dest = v->load_addr + sechdrs[i].sh_entsize; 658 659 if (sechdrs[i].sh_type != SHT_NOBITS) 660 memcpy(dest, (void *)sechdrs[i].sh_addr, 661 sechdrs[i].sh_size); 662 /* Update sh_addr to point to copy in image. */ 663 sechdrs[i].sh_addr = (unsigned long)dest; 664 665 pr_debug(" section sh_name %s sh_addr 0x%x\n", 666 secstrings + sechdrs[i].sh_name, 667 sechdrs[i].sh_addr); 668 } 669 670 /* Fix up syms, so that st_value is a pointer to location. */ 671 simplify_symbols(sechdrs, symindex, strtab, secstrings, 672 hdr->e_shnum, &mod); 673 674 /* Now do relocations. */ 675 for (i = 1; i < hdr->e_shnum; i++) { 676 const char *strtab = (char *)sechdrs[strindex].sh_addr; 677 unsigned int info = sechdrs[i].sh_info; 678 679 /* Not a valid relocation section? */ 680 if (info >= hdr->e_shnum) 681 continue; 682 683 /* Don't bother with non-allocated sections */ 684 if (!(sechdrs[info].sh_flags & SHF_ALLOC)) 685 continue; 686 687 if (sechdrs[i].sh_type == SHT_REL) 688 err = apply_relocations(sechdrs, strtab, 689 symindex, i, &mod); 690 else if (sechdrs[i].sh_type == SHT_RELA) 691 err = apply_relocate_add(sechdrs, strtab, 692 symindex, i, &mod); 693 if (err < 0) 694 return err; 695 696 } 697 } else { 698 struct elf_phdr *phdr = (struct elf_phdr *) 699 ((char *)hdr + hdr->e_phoff); 700 701 for (i = 0; i < hdr->e_phnum; i++) { 702 if (phdr->p_type == PT_LOAD) { 703 memcpy((void *)phdr->p_paddr, 704 (char *)hdr + phdr->p_offset, 705 phdr->p_filesz); 706 memset((void *)phdr->p_paddr + phdr->p_filesz, 707 0, phdr->p_memsz - phdr->p_filesz); 708 } 709 phdr++; 710 } 711 712 for (i = 0; i < hdr->e_shnum; i++) { 713 /* Internal symbols and strings. */ 714 if (sechdrs[i].sh_type == SHT_SYMTAB) { 715 symindex = i; 716 strindex = sechdrs[i].sh_link; 717 strtab = (char *)hdr + 718 sechdrs[strindex].sh_offset; 719 720 /* 721 * mark symtab's address for when we try 722 * to find the magic symbols 723 */ 724 sechdrs[i].sh_addr = (size_t) hdr + 725 sechdrs[i].sh_offset; 726 } 727 } 728 } 729 730 /* make sure it's physically written out */ 731 flush_icache_range((unsigned long)v->load_addr, 732 (unsigned long)v->load_addr + v->len); 733 734 if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) { 735 if (v->__start == 0) { 736 pr_warn("VPE loader: program does not contain a __start symbol\n"); 737 return -ENOEXEC; 738 } 739 740 if (v->shared_ptr == NULL) 741 pr_warn("VPE loader: program does not contain vpe_shared symbol.\n" 742 " Unable to use AMVP (AP/SP) facilities.\n"); 743 } 744 745 pr_info(" elf loaded\n"); 746 return 0; 747 } 748 749 static int getcwd(char *buff, int size) 750 { 751 mm_segment_t old_fs; 752 int ret; 753 754 old_fs = get_fs(); 755 set_fs(KERNEL_DS); 756 757 ret = sys_getcwd(buff, size); 758 759 set_fs(old_fs); 760 761 return ret; 762 } 763 764 /* checks VPE is unused and gets ready to load program */ 765 static int vpe_open(struct inode *inode, struct file *filp) 766 { 767 enum vpe_state state; 768 struct vpe_notifications *notifier; 769 struct vpe *v; 770 int ret; 771 772 if (VPE_MODULE_MINOR != iminor(inode)) { 773 /* assume only 1 device at the moment. */ 774 pr_warn("VPE loader: only vpe1 is supported\n"); 775 776 return -ENODEV; 777 } 778 779 v = get_vpe(aprp_cpu_index()); 780 if (v == NULL) { 781 pr_warn("VPE loader: unable to get vpe\n"); 782 783 return -ENODEV; 784 } 785 786 state = xchg(&v->state, VPE_STATE_INUSE); 787 if (state != VPE_STATE_UNUSED) { 788 pr_debug("VPE loader: tc in use dumping regs\n"); 789 790 list_for_each_entry(notifier, &v->notify, list) 791 notifier->stop(aprp_cpu_index()); 792 793 release_progmem(v->load_addr); 794 cleanup_tc(get_tc(aprp_cpu_index())); 795 } 796 797 /* this of-course trashes what was there before... */ 798 v->pbuffer = vmalloc(P_SIZE); 799 if (!v->pbuffer) { 800 pr_warn("VPE loader: unable to allocate memory\n"); 801 return -ENOMEM; 802 } 803 v->plen = P_SIZE; 804 v->load_addr = NULL; 805 v->len = 0; 806 807 v->cwd[0] = 0; 808 ret = getcwd(v->cwd, VPE_PATH_MAX); 809 if (ret < 0) 810 pr_warn("VPE loader: open, getcwd returned %d\n", ret); 811 812 v->shared_ptr = NULL; 813 v->__start = 0; 814 815 return 0; 816 } 817 818 static int vpe_release(struct inode *inode, struct file *filp) 819 { 820 #if defined(CONFIG_MIPS_VPE_LOADER_MT) || defined(CONFIG_MIPS_VPE_LOADER_CMP) 821 struct vpe *v; 822 Elf_Ehdr *hdr; 823 int ret = 0; 824 825 v = get_vpe(aprp_cpu_index()); 826 if (v == NULL) 827 return -ENODEV; 828 829 hdr = (Elf_Ehdr *) v->pbuffer; 830 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) == 0) { 831 if (vpe_elfload(v) >= 0) { 832 vpe_run(v); 833 } else { 834 pr_warn("VPE loader: ELF load failed.\n"); 835 ret = -ENOEXEC; 836 } 837 } else { 838 pr_warn("VPE loader: only elf files are supported\n"); 839 ret = -ENOEXEC; 840 } 841 842 /* It's good to be able to run the SP and if it chokes have a look at 843 the /dev/rt?. But if we reset the pointer to the shared struct we 844 lose what has happened. So perhaps if garbage is sent to the vpe 845 device, use it as a trigger for the reset. Hopefully a nice 846 executable will be along shortly. */ 847 if (ret < 0) 848 v->shared_ptr = NULL; 849 850 vfree(v->pbuffer); 851 v->plen = 0; 852 853 return ret; 854 #else 855 pr_warn("VPE loader: ELF load failed.\n"); 856 return -ENOEXEC; 857 #endif 858 } 859 860 static ssize_t vpe_write(struct file *file, const char __user *buffer, 861 size_t count, loff_t *ppos) 862 { 863 size_t ret = count; 864 struct vpe *v; 865 866 if (iminor(file_inode(file)) != VPE_MODULE_MINOR) 867 return -ENODEV; 868 869 v = get_vpe(aprp_cpu_index()); 870 871 if (v == NULL) 872 return -ENODEV; 873 874 if ((count + v->len) > v->plen) { 875 pr_warn("VPE loader: elf size too big. Perhaps strip unneeded symbols\n"); 876 return -ENOMEM; 877 } 878 879 count -= copy_from_user(v->pbuffer + v->len, buffer, count); 880 if (!count) 881 return -EFAULT; 882 883 v->len += count; 884 return ret; 885 } 886 887 const struct file_operations vpe_fops = { 888 .owner = THIS_MODULE, 889 .open = vpe_open, 890 .release = vpe_release, 891 .write = vpe_write, 892 .llseek = noop_llseek, 893 }; 894 895 void *vpe_get_shared(int index) 896 { 897 struct vpe *v = get_vpe(index); 898 899 if (v == NULL) 900 return NULL; 901 902 return v->shared_ptr; 903 } 904 EXPORT_SYMBOL(vpe_get_shared); 905 906 int vpe_notify(int index, struct vpe_notifications *notify) 907 { 908 struct vpe *v = get_vpe(index); 909 910 if (v == NULL) 911 return -1; 912 913 list_add(¬ify->list, &v->notify); 914 return 0; 915 } 916 EXPORT_SYMBOL(vpe_notify); 917 918 char *vpe_getcwd(int index) 919 { 920 struct vpe *v = get_vpe(index); 921 922 if (v == NULL) 923 return NULL; 924 925 return v->cwd; 926 } 927 EXPORT_SYMBOL(vpe_getcwd); 928 929 module_init(vpe_module_init); 930 module_exit(vpe_module_exit); 931 MODULE_DESCRIPTION("MIPS VPE Loader"); 932 MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc."); 933 MODULE_LICENSE("GPL"); 934