1 /*- 2 * Copyright (c) 2013 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Benno Rice under sponsorship from 6 * the FreeBSD Foundation. 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 34 #include <stand.h> 35 #include <bootstrap.h> 36 37 #include <efi.h> 38 #include <efilib.h> 39 40 #include "loader_efi.h" 41 42 #define M(x) ((x) * 1024 * 1024) 43 #define G(x) (1UL * (x) * 1024 * 1024 * 1024) 44 45 extern int boot_services_gone; 46 47 #if defined(__i386__) || defined(__amd64__) 48 #include <machine/cpufunc.h> 49 #include <machine/specialreg.h> 50 #include <machine/vmparam.h> 51 52 /* 53 * The code is excerpted from sys/x86/x86/identcpu.c: identify_cpu(), 54 * identify_hypervisor(), and dev/hyperv/vmbus/hyperv.c: hyperv_identify(). 55 */ 56 #define CPUID_LEAF_HV_MAXLEAF 0x40000000 57 #define CPUID_LEAF_HV_INTERFACE 0x40000001 58 #define CPUID_LEAF_HV_FEATURES 0x40000003 59 #define CPUID_LEAF_HV_LIMITS 0x40000005 60 #define CPUID_HV_IFACE_HYPERV 0x31237648 /* HV#1 */ 61 #define CPUID_HV_MSR_TIME_REFCNT 0x0002 /* MSR_HV_TIME_REF_COUNT */ 62 #define CPUID_HV_MSR_HYPERCALL 0x0020 63 64 static int 65 running_on_hyperv(void) 66 { 67 char hv_vendor[16]; 68 uint32_t regs[4]; 69 70 do_cpuid(1, regs); 71 if ((regs[2] & CPUID2_HV) == 0) 72 return (0); 73 74 do_cpuid(CPUID_LEAF_HV_MAXLEAF, regs); 75 if (regs[0] < CPUID_LEAF_HV_LIMITS) 76 return (0); 77 78 ((uint32_t *)&hv_vendor)[0] = regs[1]; 79 ((uint32_t *)&hv_vendor)[1] = regs[2]; 80 ((uint32_t *)&hv_vendor)[2] = regs[3]; 81 hv_vendor[12] = '\0'; 82 if (strcmp(hv_vendor, "Microsoft Hv") != 0) 83 return (0); 84 85 do_cpuid(CPUID_LEAF_HV_INTERFACE, regs); 86 if (regs[0] != CPUID_HV_IFACE_HYPERV) 87 return (0); 88 89 do_cpuid(CPUID_LEAF_HV_FEATURES, regs); 90 if ((regs[0] & CPUID_HV_MSR_HYPERCALL) == 0) 91 return (0); 92 if ((regs[0] & CPUID_HV_MSR_TIME_REFCNT) == 0) 93 return (0); 94 95 return (1); 96 } 97 98 static void 99 efi_verify_staging_size(unsigned long *nr_pages) 100 { 101 UINTN sz; 102 EFI_MEMORY_DESCRIPTOR *map = NULL, *p; 103 EFI_PHYSICAL_ADDRESS start, end; 104 UINTN key, dsz; 105 UINT32 dver; 106 EFI_STATUS status; 107 int i, ndesc; 108 unsigned long available_pages = 0; 109 110 sz = 0; 111 112 for (;;) { 113 status = BS->GetMemoryMap(&sz, map, &key, &dsz, &dver); 114 if (!EFI_ERROR(status)) 115 break; 116 117 if (status != EFI_BUFFER_TOO_SMALL) { 118 printf("Can't read memory map: %lu\n", 119 EFI_ERROR_CODE(status)); 120 goto out; 121 } 122 123 free(map); 124 125 /* Allocate 10 descriptors more than the size reported, 126 * to allow for any fragmentation caused by calling 127 * malloc */ 128 map = malloc(sz + (10 * dsz)); 129 if (map == NULL) { 130 printf("Unable to allocate memory\n"); 131 goto out; 132 } 133 } 134 135 ndesc = sz / dsz; 136 for (i = 0, p = map; i < ndesc; 137 i++, p = NextMemoryDescriptor(p, dsz)) { 138 start = p->PhysicalStart; 139 end = start + p->NumberOfPages * EFI_PAGE_SIZE; 140 141 if (KERNLOAD < start || KERNLOAD >= end) 142 continue; 143 144 available_pages = p->NumberOfPages - 145 ((KERNLOAD - start) >> EFI_PAGE_SHIFT); 146 break; 147 } 148 149 if (available_pages == 0) { 150 printf("Can't find valid memory map for staging area!\n"); 151 goto out; 152 } 153 154 i++; 155 p = NextMemoryDescriptor(p, dsz); 156 157 for ( ; i < ndesc; 158 i++, p = NextMemoryDescriptor(p, dsz)) { 159 if (p->Type != EfiConventionalMemory && 160 p->Type != EfiLoaderData) 161 break; 162 163 if (p->PhysicalStart != end) 164 break; 165 166 end = p->PhysicalStart + p->NumberOfPages * EFI_PAGE_SIZE; 167 168 available_pages += p->NumberOfPages; 169 } 170 171 if (*nr_pages > available_pages) { 172 printf("Staging area's size is reduced: %ld -> %ld!\n", 173 *nr_pages, available_pages); 174 *nr_pages = available_pages; 175 } 176 out: 177 free(map); 178 } 179 #endif /* __i386__ || __amd64__ */ 180 181 #ifndef EFI_STAGING_SIZE 182 #if defined(__arm__) 183 #define EFI_STAGING_SIZE M(32) 184 #else 185 #define EFI_STAGING_SIZE M(64) 186 #endif 187 #endif 188 189 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \ 190 defined(__riscv) 191 #define EFI_STAGING_2M_ALIGN 1 192 #else 193 #define EFI_STAGING_2M_ALIGN 0 194 #endif 195 196 #if defined(__amd64__) 197 #define EFI_STAGING_SLOP M(8) 198 #else 199 #define EFI_STAGING_SLOP 0 200 #endif 201 202 static u_long staging_slop = EFI_STAGING_SLOP; 203 204 EFI_PHYSICAL_ADDRESS staging, staging_end, staging_base; 205 int stage_offset_set = 0; 206 ssize_t stage_offset; 207 208 static void 209 efi_copy_free(void) 210 { 211 BS->FreePages(staging_base, (staging_end - staging_base) / 212 EFI_PAGE_SIZE); 213 stage_offset_set = 0; 214 stage_offset = 0; 215 } 216 217 #ifdef __amd64__ 218 int copy_staging = COPY_STAGING_AUTO; 219 220 static int 221 command_copy_staging(int argc, char *argv[]) 222 { 223 static const char *const mode[3] = { 224 [COPY_STAGING_ENABLE] = "enable", 225 [COPY_STAGING_DISABLE] = "disable", 226 [COPY_STAGING_AUTO] = "auto", 227 }; 228 int prev, res; 229 230 res = CMD_OK; 231 if (argc > 2) { 232 res = CMD_ERROR; 233 } else if (argc == 2) { 234 prev = copy_staging; 235 if (strcmp(argv[1], "enable") == 0) 236 copy_staging = COPY_STAGING_ENABLE; 237 else if (strcmp(argv[1], "disable") == 0) 238 copy_staging = COPY_STAGING_DISABLE; 239 else if (strcmp(argv[1], "auto") == 0) 240 copy_staging = COPY_STAGING_AUTO; 241 else { 242 printf("usage: copy_staging enable|disable|auto\n"); 243 res = CMD_ERROR; 244 } 245 if (res == CMD_OK && prev != copy_staging) { 246 printf("changed copy_staging, unloading kernel\n"); 247 unload(); 248 efi_copy_free(); 249 efi_copy_init(); 250 } 251 } else { 252 printf("copy staging: %s\n", mode[copy_staging]); 253 } 254 return (res); 255 } 256 COMMAND_SET(copy_staging, "copy_staging", "copy staging", command_copy_staging); 257 #endif 258 259 static int 260 command_staging_slop(int argc, char *argv[]) 261 { 262 char *endp; 263 u_long new, prev; 264 int res; 265 266 res = CMD_OK; 267 if (argc > 2) { 268 res = CMD_ERROR; 269 } else if (argc == 2) { 270 new = strtoul(argv[1], &endp, 0); 271 if (*endp != '\0') { 272 printf("invalid slop value\n"); 273 res = CMD_ERROR; 274 } 275 if (res == CMD_OK && staging_slop != new) { 276 printf("changed slop, unloading kernel\n"); 277 unload(); 278 efi_copy_free(); 279 efi_copy_init(); 280 } 281 } else { 282 printf("staging slop %#lx\n", staging_slop); 283 } 284 return (res); 285 } 286 COMMAND_SET(staging_slop, "staging_slop", "set staging slop", 287 command_staging_slop); 288 289 #if defined(__i386__) || defined(__amd64__) 290 /* 291 * The staging area must reside in the the first 1GB or 4GB physical 292 * memory: see elf64_exec() in 293 * boot/efi/loader/arch/amd64/elf64_freebsd.c. 294 */ 295 static EFI_PHYSICAL_ADDRESS 296 get_staging_max(void) 297 { 298 EFI_PHYSICAL_ADDRESS res; 299 300 #if defined(__i386__) 301 res = G(1); 302 #elif defined(__amd64__) 303 res = copy_staging == COPY_STAGING_ENABLE ? G(1) : G(4); 304 #endif 305 return (res); 306 } 307 #define EFI_ALLOC_METHOD AllocateMaxAddress 308 #else 309 #define EFI_ALLOC_METHOD AllocateAnyPages 310 #endif 311 312 int 313 efi_copy_init(void) 314 { 315 EFI_STATUS status; 316 unsigned long nr_pages; 317 318 nr_pages = EFI_SIZE_TO_PAGES((EFI_STAGING_SIZE)); 319 320 #if defined(__i386__) || defined(__amd64__) 321 /* 322 * We'll decrease nr_pages, if it's too big. Currently we only 323 * apply this to FreeBSD VM running on Hyper-V. Why? Please see 324 * https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=211746#c28 325 */ 326 if (running_on_hyperv()) 327 efi_verify_staging_size(&nr_pages); 328 329 staging = get_staging_max(); 330 #endif 331 status = BS->AllocatePages(EFI_ALLOC_METHOD, EfiLoaderData, 332 nr_pages, &staging); 333 if (EFI_ERROR(status)) { 334 printf("failed to allocate staging area: %lu\n", 335 EFI_ERROR_CODE(status)); 336 return (status); 337 } 338 staging_base = staging; 339 staging_end = staging + nr_pages * EFI_PAGE_SIZE; 340 341 #if EFI_STAGING_2M_ALIGN 342 /* 343 * Round the kernel load address to a 2MiB value. This is needed 344 * because the kernel builds a page table based on where it has 345 * been loaded in physical address space. As the kernel will use 346 * either a 1MiB or 2MiB page for this we need to make sure it 347 * is correctly aligned for both cases. 348 */ 349 staging = roundup2(staging, M(2)); 350 #endif 351 352 return (0); 353 } 354 355 static bool 356 efi_check_space(vm_offset_t end) 357 { 358 EFI_PHYSICAL_ADDRESS addr, new_base, new_staging; 359 EFI_STATUS status; 360 unsigned long nr_pages; 361 362 end = roundup2(end, EFI_PAGE_SIZE); 363 364 /* There is already enough space */ 365 if (end + staging_slop <= staging_end) 366 return (true); 367 368 if (boot_services_gone) { 369 if (end <= staging_end) 370 return (true); 371 panic("efi_check_space: cannot expand staging area " 372 "after boot services were exited\n"); 373 } 374 375 /* 376 * Add slop at the end: 377 * 1. amd64 kernel expects to do some very early allocations 378 * by carving out memory after kernend. Slop guarantees 379 * that it does not ovewrite anything useful. 380 * 2. It seems that initial calculation of the staging size 381 * could be somewhat smaller than actually copying in after 382 * boot services are exited. Slop avoids calling 383 * BS->AllocatePages() when it cannot work. 384 */ 385 end += staging_slop; 386 387 nr_pages = EFI_SIZE_TO_PAGES(end - staging_end); 388 #if defined(__i386__) || defined(__amd64__) 389 /* 390 * i386 needs all memory to be allocated under the 1G boundary. 391 * amd64 needs all memory to be allocated under the 1G or 4G boundary. 392 */ 393 if (end > get_staging_max()) 394 goto before_staging; 395 #endif 396 397 /* Try to allocate more space after the previous allocation */ 398 addr = staging_end; 399 status = BS->AllocatePages(AllocateAddress, EfiLoaderData, nr_pages, 400 &addr); 401 if (!EFI_ERROR(status)) { 402 staging_end = staging_end + nr_pages * EFI_PAGE_SIZE; 403 return (true); 404 } 405 406 before_staging: 407 /* Try allocating space before the previous allocation */ 408 if (staging < nr_pages * EFI_PAGE_SIZE) 409 goto expand; 410 addr = staging - nr_pages * EFI_PAGE_SIZE; 411 #if EFI_STAGING_2M_ALIGN 412 /* See efi_copy_init for why this is needed */ 413 addr = rounddown2(addr, M(2)); 414 #endif 415 nr_pages = EFI_SIZE_TO_PAGES(staging_base - addr); 416 status = BS->AllocatePages(AllocateAddress, EfiLoaderData, nr_pages, 417 &addr); 418 if (!EFI_ERROR(status)) { 419 /* 420 * Move the old allocation and update the state so 421 * translation still works. 422 */ 423 staging_base = addr; 424 memmove((void *)(uintptr_t)staging_base, 425 (void *)(uintptr_t)staging, staging_end - staging); 426 stage_offset -= staging - staging_base; 427 staging = staging_base; 428 return (true); 429 } 430 431 expand: 432 nr_pages = EFI_SIZE_TO_PAGES(end - (vm_offset_t)staging); 433 #if EFI_STAGING_2M_ALIGN 434 nr_pages += M(2) / EFI_PAGE_SIZE; 435 #endif 436 #if defined(__i386__) || defined(__amd64__) 437 new_base = get_staging_max(); 438 #endif 439 status = BS->AllocatePages(EFI_ALLOC_METHOD, EfiLoaderData, 440 nr_pages, &new_base); 441 if (!EFI_ERROR(status)) { 442 #if EFI_STAGING_2M_ALIGN 443 new_staging = roundup2(new_base, M(2)); 444 #else 445 new_staging = new_base; 446 #endif 447 /* 448 * Move the old allocation and update the state so 449 * translation still works. 450 */ 451 memcpy((void *)(uintptr_t)new_staging, 452 (void *)(uintptr_t)staging, staging_end - staging); 453 BS->FreePages(staging_base, (staging_end - staging_base) / 454 EFI_PAGE_SIZE); 455 stage_offset -= staging - new_staging; 456 staging = new_staging; 457 staging_end = new_base + nr_pages * EFI_PAGE_SIZE; 458 staging_base = new_base; 459 return (true); 460 } 461 462 printf("efi_check_space: Unable to expand staging area\n"); 463 return (false); 464 } 465 466 void * 467 efi_translate(vm_offset_t ptr) 468 { 469 470 return ((void *)(ptr + stage_offset)); 471 } 472 473 ssize_t 474 efi_copyin(const void *src, vm_offset_t dest, const size_t len) 475 { 476 477 if (!stage_offset_set) { 478 stage_offset = (vm_offset_t)staging - dest; 479 stage_offset_set = 1; 480 } 481 482 /* XXX: Callers do not check for failure. */ 483 if (!efi_check_space(dest + stage_offset + len)) { 484 errno = ENOMEM; 485 return (-1); 486 } 487 bcopy(src, (void *)(dest + stage_offset), len); 488 return (len); 489 } 490 491 ssize_t 492 efi_copyout(const vm_offset_t src, void *dest, const size_t len) 493 { 494 495 /* XXX: Callers do not check for failure. */ 496 if (src + stage_offset + len > staging_end) { 497 errno = ENOMEM; 498 return (-1); 499 } 500 bcopy((void *)(src + stage_offset), dest, len); 501 return (len); 502 } 503 504 ssize_t 505 efi_readin(readin_handle_t fd, vm_offset_t dest, const size_t len) 506 { 507 508 if (!stage_offset_set) { 509 stage_offset = (vm_offset_t)staging - dest; 510 stage_offset_set = 1; 511 } 512 513 if (!efi_check_space(dest + stage_offset + len)) { 514 errno = ENOMEM; 515 return (-1); 516 } 517 return (VECTX_READ(fd, (void *)(dest + stage_offset), len)); 518 } 519 520 void 521 efi_copy_finish(void) 522 { 523 uint64_t *src, *dst, *last; 524 525 src = (uint64_t *)(uintptr_t)staging; 526 dst = (uint64_t *)(uintptr_t)(staging - stage_offset); 527 last = (uint64_t *)(uintptr_t)staging_end; 528 529 while (src < last) 530 *dst++ = *src++; 531 } 532 533 void 534 efi_copy_finish_nop(void) 535 { 536 } 537