1 /* 2 * EFI application memory management 3 * 4 * Copyright (c) 2016 Alexander Graf 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #include <common.h> 10 #include <efi_loader.h> 11 #include <malloc.h> 12 #include <asm/global_data.h> 13 #include <libfdt_env.h> 14 #include <linux/list_sort.h> 15 #include <inttypes.h> 16 #include <watchdog.h> 17 18 DECLARE_GLOBAL_DATA_PTR; 19 20 struct efi_mem_list { 21 struct list_head link; 22 struct efi_mem_desc desc; 23 }; 24 25 #define EFI_CARVE_NO_OVERLAP -1 26 #define EFI_CARVE_LOOP_AGAIN -2 27 #define EFI_CARVE_OVERLAPS_NONRAM -3 28 29 /* This list contains all memory map items */ 30 LIST_HEAD(efi_mem); 31 32 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER 33 void *efi_bounce_buffer; 34 #endif 35 36 /* 37 * U-Boot services each EFI AllocatePool request as a separate 38 * (multiple) page allocation. We have to track the number of pages 39 * to be able to free the correct amount later. 40 * EFI requires 8 byte alignment for pool allocations, so we can 41 * prepend each allocation with an 64 bit header tracking the 42 * allocation size, and hand out the remainder to the caller. 43 */ 44 struct efi_pool_allocation { 45 u64 num_pages; 46 char data[]; 47 }; 48 49 /* 50 * Sorts the memory list from highest address to lowest address 51 * 52 * When allocating memory we should always start from the highest 53 * address chunk, so sort the memory list such that the first list 54 * iterator gets the highest address and goes lower from there. 55 */ 56 static int efi_mem_cmp(void *priv, struct list_head *a, struct list_head *b) 57 { 58 struct efi_mem_list *mema = list_entry(a, struct efi_mem_list, link); 59 struct efi_mem_list *memb = list_entry(b, struct efi_mem_list, link); 60 61 if (mema->desc.physical_start == memb->desc.physical_start) 62 return 0; 63 else if (mema->desc.physical_start < memb->desc.physical_start) 64 return 1; 65 else 66 return -1; 67 } 68 69 static void efi_mem_sort(void) 70 { 71 list_sort(NULL, &efi_mem, efi_mem_cmp); 72 } 73 74 /* 75 * Unmaps all memory occupied by the carve_desc region from the 76 * list entry pointed to by map. 77 * 78 * Returns EFI_CARVE_NO_OVERLAP if the regions don't overlap. 79 * Returns EFI_CARVE_OVERLAPS_NONRAM if the carve and map overlap, 80 * and the map contains anything but free ram. 81 * (only when overlap_only_ram is true) 82 * Returns EFI_CARVE_LOOP_AGAIN if the mapping list should be traversed 83 * again, as it has been altered 84 * Returns the number of overlapping pages. The pages are removed from 85 * the mapping list. 86 * 87 * In case of EFI_CARVE_OVERLAPS_NONRAM it is the callers responsibility 88 * to readd the already carved out pages to the mapping. 89 */ 90 static int efi_mem_carve_out(struct efi_mem_list *map, 91 struct efi_mem_desc *carve_desc, 92 bool overlap_only_ram) 93 { 94 struct efi_mem_list *newmap; 95 struct efi_mem_desc *map_desc = &map->desc; 96 uint64_t map_start = map_desc->physical_start; 97 uint64_t map_end = map_start + (map_desc->num_pages << EFI_PAGE_SHIFT); 98 uint64_t carve_start = carve_desc->physical_start; 99 uint64_t carve_end = carve_start + 100 (carve_desc->num_pages << EFI_PAGE_SHIFT); 101 102 /* check whether we're overlapping */ 103 if ((carve_end <= map_start) || (carve_start >= map_end)) 104 return EFI_CARVE_NO_OVERLAP; 105 106 /* We're overlapping with non-RAM, warn the caller if desired */ 107 if (overlap_only_ram && (map_desc->type != EFI_CONVENTIONAL_MEMORY)) 108 return EFI_CARVE_OVERLAPS_NONRAM; 109 110 /* Sanitize carve_start and carve_end to lie within our bounds */ 111 carve_start = max(carve_start, map_start); 112 carve_end = min(carve_end, map_end); 113 114 /* Carving at the beginning of our map? Just move it! */ 115 if (carve_start == map_start) { 116 if (map_end == carve_end) { 117 /* Full overlap, just remove map */ 118 list_del(&map->link); 119 free(map); 120 } else { 121 map->desc.physical_start = carve_end; 122 map->desc.num_pages = (map_end - carve_end) 123 >> EFI_PAGE_SHIFT; 124 } 125 126 return (carve_end - carve_start) >> EFI_PAGE_SHIFT; 127 } 128 129 /* 130 * Overlapping maps, just split the list map at carve_start, 131 * it will get moved or removed in the next iteration. 132 * 133 * [ map_desc |__carve_start__| newmap ] 134 */ 135 136 /* Create a new map from [ carve_start ... map_end ] */ 137 newmap = calloc(1, sizeof(*newmap)); 138 newmap->desc = map->desc; 139 newmap->desc.physical_start = carve_start; 140 newmap->desc.num_pages = (map_end - carve_start) >> EFI_PAGE_SHIFT; 141 /* Insert before current entry (descending address order) */ 142 list_add_tail(&newmap->link, &map->link); 143 144 /* Shrink the map to [ map_start ... carve_start ] */ 145 map_desc->num_pages = (carve_start - map_start) >> EFI_PAGE_SHIFT; 146 147 return EFI_CARVE_LOOP_AGAIN; 148 } 149 150 uint64_t efi_add_memory_map(uint64_t start, uint64_t pages, int memory_type, 151 bool overlap_only_ram) 152 { 153 struct list_head *lhandle; 154 struct efi_mem_list *newlist; 155 bool carve_again; 156 uint64_t carved_pages = 0; 157 158 debug("%s: 0x%" PRIx64 " 0x%" PRIx64 " %d %s\n", __func__, 159 start, pages, memory_type, overlap_only_ram ? "yes" : "no"); 160 161 if (!pages) 162 return start; 163 164 newlist = calloc(1, sizeof(*newlist)); 165 newlist->desc.type = memory_type; 166 newlist->desc.physical_start = start; 167 newlist->desc.virtual_start = start; 168 newlist->desc.num_pages = pages; 169 170 switch (memory_type) { 171 case EFI_RUNTIME_SERVICES_CODE: 172 case EFI_RUNTIME_SERVICES_DATA: 173 newlist->desc.attribute = (1 << EFI_MEMORY_WB_SHIFT) | 174 (1ULL << EFI_MEMORY_RUNTIME_SHIFT); 175 break; 176 case EFI_MMAP_IO: 177 newlist->desc.attribute = 1ULL << EFI_MEMORY_RUNTIME_SHIFT; 178 break; 179 default: 180 newlist->desc.attribute = 1 << EFI_MEMORY_WB_SHIFT; 181 break; 182 } 183 184 /* Add our new map */ 185 do { 186 carve_again = false; 187 list_for_each(lhandle, &efi_mem) { 188 struct efi_mem_list *lmem; 189 int r; 190 191 lmem = list_entry(lhandle, struct efi_mem_list, link); 192 r = efi_mem_carve_out(lmem, &newlist->desc, 193 overlap_only_ram); 194 switch (r) { 195 case EFI_CARVE_OVERLAPS_NONRAM: 196 /* 197 * The user requested to only have RAM overlaps, 198 * but we hit a non-RAM region. Error out. 199 */ 200 return 0; 201 case EFI_CARVE_NO_OVERLAP: 202 /* Just ignore this list entry */ 203 break; 204 case EFI_CARVE_LOOP_AGAIN: 205 /* 206 * We split an entry, but need to loop through 207 * the list again to actually carve it. 208 */ 209 carve_again = true; 210 break; 211 default: 212 /* We carved a number of pages */ 213 carved_pages += r; 214 carve_again = true; 215 break; 216 } 217 218 if (carve_again) { 219 /* The list changed, we need to start over */ 220 break; 221 } 222 } 223 } while (carve_again); 224 225 if (overlap_only_ram && (carved_pages != pages)) { 226 /* 227 * The payload wanted to have RAM overlaps, but we overlapped 228 * with an unallocated region. Error out. 229 */ 230 return 0; 231 } 232 233 /* Add our new map */ 234 list_add_tail(&newlist->link, &efi_mem); 235 236 /* And make sure memory is listed in descending order */ 237 efi_mem_sort(); 238 239 return start; 240 } 241 242 static uint64_t efi_find_free_memory(uint64_t len, uint64_t max_addr) 243 { 244 struct list_head *lhandle; 245 246 list_for_each(lhandle, &efi_mem) { 247 struct efi_mem_list *lmem = list_entry(lhandle, 248 struct efi_mem_list, link); 249 struct efi_mem_desc *desc = &lmem->desc; 250 uint64_t desc_len = desc->num_pages << EFI_PAGE_SHIFT; 251 uint64_t desc_end = desc->physical_start + desc_len; 252 uint64_t curmax = min(max_addr, desc_end); 253 uint64_t ret = curmax - len; 254 255 /* We only take memory from free RAM */ 256 if (desc->type != EFI_CONVENTIONAL_MEMORY) 257 continue; 258 259 /* Out of bounds for max_addr */ 260 if ((ret + len) > max_addr) 261 continue; 262 263 /* Out of bounds for upper map limit */ 264 if ((ret + len) > desc_end) 265 continue; 266 267 /* Out of bounds for lower map limit */ 268 if (ret < desc->physical_start) 269 continue; 270 271 /* Return the highest address in this map within bounds */ 272 return ret; 273 } 274 275 return 0; 276 } 277 278 efi_status_t efi_allocate_pages(int type, int memory_type, 279 unsigned long pages, uint64_t *memory) 280 { 281 u64 len = pages << EFI_PAGE_SHIFT; 282 efi_status_t r = EFI_SUCCESS; 283 uint64_t addr; 284 285 switch (type) { 286 case 0: 287 /* Any page */ 288 addr = efi_find_free_memory(len, gd->start_addr_sp); 289 if (!addr) { 290 r = EFI_NOT_FOUND; 291 break; 292 } 293 break; 294 case 1: 295 /* Max address */ 296 addr = efi_find_free_memory(len, *memory); 297 if (!addr) { 298 r = EFI_NOT_FOUND; 299 break; 300 } 301 break; 302 case 2: 303 /* Exact address, reserve it. The addr is already in *memory. */ 304 addr = *memory; 305 break; 306 default: 307 /* UEFI doesn't specify other allocation types */ 308 r = EFI_INVALID_PARAMETER; 309 break; 310 } 311 312 if (r == EFI_SUCCESS) { 313 uint64_t ret; 314 315 /* Reserve that map in our memory maps */ 316 ret = efi_add_memory_map(addr, pages, memory_type, true); 317 if (ret == addr) { 318 *memory = addr; 319 } else { 320 /* Map would overlap, bail out */ 321 r = EFI_OUT_OF_RESOURCES; 322 } 323 } 324 325 return r; 326 } 327 328 void *efi_alloc(uint64_t len, int memory_type) 329 { 330 uint64_t ret = 0; 331 uint64_t pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT; 332 efi_status_t r; 333 334 r = efi_allocate_pages(0, memory_type, pages, &ret); 335 if (r == EFI_SUCCESS) 336 return (void*)(uintptr_t)ret; 337 338 return NULL; 339 } 340 341 efi_status_t efi_free_pages(uint64_t memory, unsigned long pages) 342 { 343 uint64_t r = 0; 344 345 r = efi_add_memory_map(memory, pages, EFI_CONVENTIONAL_MEMORY, false); 346 /* Merging of adjacent free regions is missing */ 347 348 if (r == memory) 349 return EFI_SUCCESS; 350 351 return EFI_NOT_FOUND; 352 } 353 354 efi_status_t efi_allocate_pool(int pool_type, unsigned long size, 355 void **buffer) 356 { 357 efi_status_t r; 358 efi_physical_addr_t t; 359 u64 num_pages = (size + sizeof(u64) + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT; 360 361 if (size == 0) { 362 *buffer = NULL; 363 return EFI_SUCCESS; 364 } 365 366 r = efi_allocate_pages(0, pool_type, num_pages, &t); 367 368 if (r == EFI_SUCCESS) { 369 struct efi_pool_allocation *alloc = (void *)(uintptr_t)t; 370 alloc->num_pages = num_pages; 371 *buffer = alloc->data; 372 } 373 374 return r; 375 } 376 377 efi_status_t efi_free_pool(void *buffer) 378 { 379 efi_status_t r; 380 struct efi_pool_allocation *alloc; 381 382 alloc = container_of(buffer, struct efi_pool_allocation, data); 383 /* Sanity check, was the supplied address returned by allocate_pool */ 384 assert(((uintptr_t)alloc & EFI_PAGE_MASK) == 0); 385 386 r = efi_free_pages((uintptr_t)alloc, alloc->num_pages); 387 388 return r; 389 } 390 391 efi_status_t efi_get_memory_map(unsigned long *memory_map_size, 392 struct efi_mem_desc *memory_map, 393 unsigned long *map_key, 394 unsigned long *descriptor_size, 395 uint32_t *descriptor_version) 396 { 397 ulong map_size = 0; 398 int map_entries = 0; 399 struct list_head *lhandle; 400 unsigned long provided_map_size = *memory_map_size; 401 402 list_for_each(lhandle, &efi_mem) 403 map_entries++; 404 405 map_size = map_entries * sizeof(struct efi_mem_desc); 406 407 *memory_map_size = map_size; 408 409 if (descriptor_size) 410 *descriptor_size = sizeof(struct efi_mem_desc); 411 412 if (descriptor_version) 413 *descriptor_version = EFI_MEMORY_DESCRIPTOR_VERSION; 414 415 if (provided_map_size < map_size) 416 return EFI_BUFFER_TOO_SMALL; 417 418 /* Copy list into array */ 419 if (memory_map) { 420 /* Return the list in ascending order */ 421 memory_map = &memory_map[map_entries - 1]; 422 list_for_each(lhandle, &efi_mem) { 423 struct efi_mem_list *lmem; 424 425 lmem = list_entry(lhandle, struct efi_mem_list, link); 426 *memory_map = lmem->desc; 427 memory_map--; 428 } 429 } 430 431 return EFI_SUCCESS; 432 } 433 434 __weak void efi_add_known_memory(void) 435 { 436 int i; 437 438 /* Add RAM */ 439 for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) { 440 u64 ram_start = gd->bd->bi_dram[i].start; 441 u64 ram_size = gd->bd->bi_dram[i].size; 442 u64 start = (ram_start + EFI_PAGE_MASK) & ~EFI_PAGE_MASK; 443 u64 pages = (ram_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT; 444 445 efi_add_memory_map(start, pages, EFI_CONVENTIONAL_MEMORY, 446 false); 447 } 448 } 449 450 int efi_memory_init(void) 451 { 452 unsigned long runtime_start, runtime_end, runtime_pages; 453 unsigned long uboot_start, uboot_pages; 454 unsigned long uboot_stack_size = 16 * 1024 * 1024; 455 456 efi_add_known_memory(); 457 458 /* Add U-Boot */ 459 uboot_start = (gd->start_addr_sp - uboot_stack_size) & ~EFI_PAGE_MASK; 460 uboot_pages = (gd->ram_top - uboot_start) >> EFI_PAGE_SHIFT; 461 efi_add_memory_map(uboot_start, uboot_pages, EFI_LOADER_DATA, false); 462 463 /* Add Runtime Services */ 464 runtime_start = (ulong)&__efi_runtime_start & ~EFI_PAGE_MASK; 465 runtime_end = (ulong)&__efi_runtime_stop; 466 runtime_end = (runtime_end + EFI_PAGE_MASK) & ~EFI_PAGE_MASK; 467 runtime_pages = (runtime_end - runtime_start) >> EFI_PAGE_SHIFT; 468 efi_add_memory_map(runtime_start, runtime_pages, 469 EFI_RUNTIME_SERVICES_CODE, false); 470 471 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER 472 /* Request a 32bit 64MB bounce buffer region */ 473 uint64_t efi_bounce_buffer_addr = 0xffffffff; 474 475 if (efi_allocate_pages(1, EFI_LOADER_DATA, 476 (64 * 1024 * 1024) >> EFI_PAGE_SHIFT, 477 &efi_bounce_buffer_addr) != EFI_SUCCESS) 478 return -1; 479 480 efi_bounce_buffer = (void*)(uintptr_t)efi_bounce_buffer_addr; 481 #endif 482 483 return 0; 484 } 485