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