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 #if defined(__i386__) || defined(__amd64__) 43 #include <machine/cpufunc.h> 44 #include <machine/specialreg.h> 45 #include <machine/vmparam.h> 46 47 /* 48 * The code is excerpted from sys/x86/x86/identcpu.c: identify_cpu(), 49 * identify_hypervisor(), and dev/hyperv/vmbus/hyperv.c: hyperv_identify(). 50 */ 51 #define CPUID_LEAF_HV_MAXLEAF 0x40000000 52 #define CPUID_LEAF_HV_INTERFACE 0x40000001 53 #define CPUID_LEAF_HV_FEATURES 0x40000003 54 #define CPUID_LEAF_HV_LIMITS 0x40000005 55 #define CPUID_HV_IFACE_HYPERV 0x31237648 /* HV#1 */ 56 #define CPUID_HV_MSR_TIME_REFCNT 0x0002 /* MSR_HV_TIME_REF_COUNT */ 57 #define CPUID_HV_MSR_HYPERCALL 0x0020 58 59 static int 60 running_on_hyperv(void) 61 { 62 char hv_vendor[16]; 63 uint32_t regs[4]; 64 65 do_cpuid(1, regs); 66 if ((regs[2] & CPUID2_HV) == 0) 67 return (0); 68 69 do_cpuid(CPUID_LEAF_HV_MAXLEAF, regs); 70 if (regs[0] < CPUID_LEAF_HV_LIMITS) 71 return (0); 72 73 ((uint32_t *)&hv_vendor)[0] = regs[1]; 74 ((uint32_t *)&hv_vendor)[1] = regs[2]; 75 ((uint32_t *)&hv_vendor)[2] = regs[3]; 76 hv_vendor[12] = '\0'; 77 if (strcmp(hv_vendor, "Microsoft Hv") != 0) 78 return (0); 79 80 do_cpuid(CPUID_LEAF_HV_INTERFACE, regs); 81 if (regs[0] != CPUID_HV_IFACE_HYPERV) 82 return (0); 83 84 do_cpuid(CPUID_LEAF_HV_FEATURES, regs); 85 if ((regs[0] & CPUID_HV_MSR_HYPERCALL) == 0) 86 return (0); 87 if ((regs[0] & CPUID_HV_MSR_TIME_REFCNT) == 0) 88 return (0); 89 90 return (1); 91 } 92 93 static void 94 efi_verify_staging_size(unsigned long *nr_pages) 95 { 96 UINTN sz; 97 EFI_MEMORY_DESCRIPTOR *map = NULL, *p; 98 EFI_PHYSICAL_ADDRESS start, end; 99 UINTN key, dsz; 100 UINT32 dver; 101 EFI_STATUS status; 102 int i, ndesc; 103 unsigned long available_pages = 0; 104 105 sz = 0; 106 107 for (;;) { 108 status = BS->GetMemoryMap(&sz, map, &key, &dsz, &dver); 109 if (!EFI_ERROR(status)) 110 break; 111 112 if (status != EFI_BUFFER_TOO_SMALL) { 113 printf("Can't read memory map: %lu\n", 114 EFI_ERROR_CODE(status)); 115 goto out; 116 } 117 118 free(map); 119 120 /* Allocate 10 descriptors more than the size reported, 121 * to allow for any fragmentation caused by calling 122 * malloc */ 123 map = malloc(sz + (10 * dsz)); 124 if (map == NULL) { 125 printf("Unable to allocate memory\n"); 126 goto out; 127 } 128 } 129 130 ndesc = sz / dsz; 131 for (i = 0, p = map; i < ndesc; 132 i++, p = NextMemoryDescriptor(p, dsz)) { 133 start = p->PhysicalStart; 134 end = start + p->NumberOfPages * EFI_PAGE_SIZE; 135 136 if (KERNLOAD < start || KERNLOAD >= end) 137 continue; 138 139 available_pages = p->NumberOfPages - 140 ((KERNLOAD - start) >> EFI_PAGE_SHIFT); 141 break; 142 } 143 144 if (available_pages == 0) { 145 printf("Can't find valid memory map for staging area!\n"); 146 goto out; 147 } 148 149 i++; 150 p = NextMemoryDescriptor(p, dsz); 151 152 for ( ; i < ndesc; 153 i++, p = NextMemoryDescriptor(p, dsz)) { 154 if (p->Type != EfiConventionalMemory && 155 p->Type != EfiLoaderData) 156 break; 157 158 if (p->PhysicalStart != end) 159 break; 160 161 end = p->PhysicalStart + p->NumberOfPages * EFI_PAGE_SIZE; 162 163 available_pages += p->NumberOfPages; 164 } 165 166 if (*nr_pages > available_pages) { 167 printf("Staging area's size is reduced: %ld -> %ld!\n", 168 *nr_pages, available_pages); 169 *nr_pages = available_pages; 170 } 171 out: 172 free(map); 173 } 174 #endif /* __i386__ || __amd64__ */ 175 176 #ifndef EFI_STAGING_SIZE 177 #if defined(__amd64__) 178 #define EFI_STAGING_SIZE 100 179 #elif defined(__arm__) 180 #define EFI_STAGING_SIZE 32 181 #else 182 #define EFI_STAGING_SIZE 64 183 #endif 184 #endif 185 186 EFI_PHYSICAL_ADDRESS staging, staging_end, staging_base; 187 int stage_offset_set = 0; 188 ssize_t stage_offset; 189 190 int 191 efi_copy_init(void) 192 { 193 EFI_STATUS status; 194 195 unsigned long nr_pages; 196 197 nr_pages = EFI_SIZE_TO_PAGES((EFI_STAGING_SIZE) * 1024 * 1024); 198 199 #if defined(__i386__) || defined(__amd64__) 200 /* 201 * We'll decrease nr_pages, if it's too big. Currently we only 202 * apply this to FreeBSD VM running on Hyper-V. Why? Please see 203 * https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=211746#c28 204 */ 205 if (running_on_hyperv()) 206 efi_verify_staging_size(&nr_pages); 207 208 /* 209 * The staging area must reside in the the first 1GB physical 210 * memory: see elf64_exec() in 211 * boot/efi/loader/arch/amd64/elf64_freebsd.c. 212 */ 213 staging = 1024*1024*1024; 214 status = BS->AllocatePages(AllocateMaxAddress, EfiLoaderData, 215 nr_pages, &staging); 216 #else 217 status = BS->AllocatePages(AllocateAnyPages, EfiLoaderData, 218 nr_pages, &staging); 219 #endif 220 if (EFI_ERROR(status)) { 221 printf("failed to allocate staging area: %lu\n", 222 EFI_ERROR_CODE(status)); 223 return (status); 224 } 225 staging_base = staging; 226 staging_end = staging + nr_pages * EFI_PAGE_SIZE; 227 228 #if defined(__aarch64__) || defined(__arm__) || defined(__riscv) 229 /* 230 * Round the kernel load address to a 2MiB value. This is needed 231 * because the kernel builds a page table based on where it has 232 * been loaded in physical address space. As the kernel will use 233 * either a 1MiB or 2MiB page for this we need to make sure it 234 * is correctly aligned for both cases. 235 */ 236 staging = roundup2(staging, 2 * 1024 * 1024); 237 #endif 238 239 return (0); 240 } 241 242 static bool 243 efi_check_space(vm_offset_t end) 244 { 245 EFI_PHYSICAL_ADDRESS addr; 246 EFI_STATUS status; 247 unsigned long nr_pages; 248 249 /* There is already enough space */ 250 if (end <= staging_end) 251 return (true); 252 253 end = roundup2(end, EFI_PAGE_SIZE); 254 nr_pages = EFI_SIZE_TO_PAGES(end - staging_end); 255 256 #if defined(__i386__) || defined(__amd64__) 257 /* X86 needs all memory to be allocated under the 1G boundary */ 258 if (end > 1024*1024*1024) 259 goto before_staging; 260 #endif 261 262 /* Try to allocate more space after the previous allocation */ 263 addr = staging_end; 264 status = BS->AllocatePages(AllocateAddress, EfiLoaderData, nr_pages, 265 &addr); 266 if (!EFI_ERROR(status)) { 267 staging_end = staging_end + nr_pages * EFI_PAGE_SIZE; 268 return (true); 269 } 270 271 before_staging: 272 /* Try allocating space before the previous allocation */ 273 if (staging < nr_pages * EFI_PAGE_SIZE) { 274 printf("Not enough space before allocation\n"); 275 return (false); 276 } 277 addr = staging - nr_pages * EFI_PAGE_SIZE; 278 #if defined(__aarch64__) || defined(__arm__) || defined(__riscv) 279 /* See efi_copy_init for why this is needed */ 280 addr = rounddown2(addr, 2 * 1024 * 1024); 281 #endif 282 nr_pages = EFI_SIZE_TO_PAGES(staging_base - addr); 283 status = BS->AllocatePages(AllocateAddress, EfiLoaderData, nr_pages, 284 &addr); 285 if (!EFI_ERROR(status)) { 286 /* 287 * Move the old allocation and update the state so 288 * translation still works. 289 */ 290 staging_base = addr; 291 memmove((void *)(uintptr_t)staging_base, 292 (void *)(uintptr_t)staging, staging_end - staging); 293 stage_offset -= (staging - staging_base); 294 staging = staging_base; 295 return (true); 296 } 297 298 printf("efi_check_space: Unable to expand staging area\n"); 299 return (false); 300 } 301 302 void * 303 efi_translate(vm_offset_t ptr) 304 { 305 306 return ((void *)(ptr + stage_offset)); 307 } 308 309 ssize_t 310 efi_copyin(const void *src, vm_offset_t dest, const size_t len) 311 { 312 313 if (!stage_offset_set) { 314 stage_offset = (vm_offset_t)staging - dest; 315 stage_offset_set = 1; 316 } 317 318 /* XXX: Callers do not check for failure. */ 319 if (!efi_check_space(dest + stage_offset + len)) { 320 errno = ENOMEM; 321 return (-1); 322 } 323 bcopy(src, (void *)(dest + stage_offset), len); 324 return (len); 325 } 326 327 ssize_t 328 efi_copyout(const vm_offset_t src, void *dest, const size_t len) 329 { 330 331 /* XXX: Callers do not check for failure. */ 332 if (src + stage_offset + len > staging_end) { 333 errno = ENOMEM; 334 return (-1); 335 } 336 bcopy((void *)(src + stage_offset), dest, len); 337 return (len); 338 } 339 340 341 ssize_t 342 efi_readin(readin_handle_t fd, vm_offset_t dest, const size_t len) 343 { 344 345 if (!stage_offset_set) { 346 stage_offset = (vm_offset_t)staging - dest; 347 stage_offset_set = 1; 348 } 349 350 if (!efi_check_space(dest + stage_offset + len)) { 351 errno = ENOMEM; 352 return (-1); 353 } 354 return (VECTX_READ(fd, (void *)(dest + stage_offset), len)); 355 } 356 357 void 358 efi_copy_finish(void) 359 { 360 uint64_t *src, *dst, *last; 361 362 src = (uint64_t *)(uintptr_t)staging; 363 dst = (uint64_t *)(uintptr_t)(staging - stage_offset); 364 last = (uint64_t *)(uintptr_t)staging_end; 365 366 while (src < last) 367 *dst++ = *src++; 368 } 369