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 } 120 121 map_desc->physical_start = carve_end; 122 map_desc->num_pages = (map_end - carve_end) >> EFI_PAGE_SHIFT; 123 return (carve_end - carve_start) >> EFI_PAGE_SHIFT; 124 } 125 126 /* 127 * Overlapping maps, just split the list map at carve_start, 128 * it will get moved or removed in the next iteration. 129 * 130 * [ map_desc |__carve_start__| newmap ] 131 */ 132 133 /* Create a new map from [ carve_start ... map_end ] */ 134 newmap = calloc(1, sizeof(*newmap)); 135 newmap->desc = map->desc; 136 newmap->desc.physical_start = carve_start; 137 newmap->desc.num_pages = (map_end - carve_start) >> EFI_PAGE_SHIFT; 138 /* Insert before current entry (descending address order) */ 139 list_add_tail(&newmap->link, &map->link); 140 141 /* Shrink the map to [ map_start ... carve_start ] */ 142 map_desc->num_pages = (carve_start - map_start) >> EFI_PAGE_SHIFT; 143 144 return EFI_CARVE_LOOP_AGAIN; 145 } 146 147 uint64_t efi_add_memory_map(uint64_t start, uint64_t pages, int memory_type, 148 bool overlap_only_ram) 149 { 150 struct list_head *lhandle; 151 struct efi_mem_list *newlist; 152 bool carve_again; 153 uint64_t carved_pages = 0; 154 155 debug("%s: 0x%" PRIx64 " 0x%" PRIx64 " %d %s\n", __func__, 156 start, pages, memory_type, overlap_only_ram ? "yes" : "no"); 157 158 if (!pages) 159 return start; 160 161 newlist = calloc(1, sizeof(*newlist)); 162 newlist->desc.type = memory_type; 163 newlist->desc.physical_start = start; 164 newlist->desc.virtual_start = start; 165 newlist->desc.num_pages = pages; 166 167 switch (memory_type) { 168 case EFI_RUNTIME_SERVICES_CODE: 169 case EFI_RUNTIME_SERVICES_DATA: 170 newlist->desc.attribute = (1 << EFI_MEMORY_WB_SHIFT) | 171 (1ULL << EFI_MEMORY_RUNTIME_SHIFT); 172 break; 173 case EFI_MMAP_IO: 174 newlist->desc.attribute = 1ULL << EFI_MEMORY_RUNTIME_SHIFT; 175 break; 176 default: 177 newlist->desc.attribute = 1 << EFI_MEMORY_WB_SHIFT; 178 break; 179 } 180 181 /* Add our new map */ 182 do { 183 carve_again = false; 184 list_for_each(lhandle, &efi_mem) { 185 struct efi_mem_list *lmem; 186 int r; 187 188 lmem = list_entry(lhandle, struct efi_mem_list, link); 189 r = efi_mem_carve_out(lmem, &newlist->desc, 190 overlap_only_ram); 191 switch (r) { 192 case EFI_CARVE_OVERLAPS_NONRAM: 193 /* 194 * The user requested to only have RAM overlaps, 195 * but we hit a non-RAM region. Error out. 196 */ 197 return 0; 198 case EFI_CARVE_NO_OVERLAP: 199 /* Just ignore this list entry */ 200 break; 201 case EFI_CARVE_LOOP_AGAIN: 202 /* 203 * We split an entry, but need to loop through 204 * the list again to actually carve it. 205 */ 206 carve_again = true; 207 break; 208 default: 209 /* We carved a number of pages */ 210 carved_pages += r; 211 carve_again = true; 212 break; 213 } 214 215 if (carve_again) { 216 /* The list changed, we need to start over */ 217 break; 218 } 219 } 220 } while (carve_again); 221 222 if (overlap_only_ram && (carved_pages != pages)) { 223 /* 224 * The payload wanted to have RAM overlaps, but we overlapped 225 * with an unallocated region. Error out. 226 */ 227 return 0; 228 } 229 230 /* Add our new map */ 231 list_add_tail(&newlist->link, &efi_mem); 232 233 /* And make sure memory is listed in descending order */ 234 efi_mem_sort(); 235 236 return start; 237 } 238 239 static uint64_t efi_find_free_memory(uint64_t len, uint64_t max_addr) 240 { 241 struct list_head *lhandle; 242 243 list_for_each(lhandle, &efi_mem) { 244 struct efi_mem_list *lmem = list_entry(lhandle, 245 struct efi_mem_list, link); 246 struct efi_mem_desc *desc = &lmem->desc; 247 uint64_t desc_len = desc->num_pages << EFI_PAGE_SHIFT; 248 uint64_t desc_end = desc->physical_start + desc_len; 249 uint64_t curmax = min(max_addr, desc_end); 250 uint64_t ret = curmax - len; 251 252 /* We only take memory from free RAM */ 253 if (desc->type != EFI_CONVENTIONAL_MEMORY) 254 continue; 255 256 /* Out of bounds for max_addr */ 257 if ((ret + len) > max_addr) 258 continue; 259 260 /* Out of bounds for upper map limit */ 261 if ((ret + len) > desc_end) 262 continue; 263 264 /* Out of bounds for lower map limit */ 265 if (ret < desc->physical_start) 266 continue; 267 268 /* Return the highest address in this map within bounds */ 269 return ret; 270 } 271 272 return 0; 273 } 274 275 efi_status_t efi_allocate_pages(int type, int memory_type, 276 unsigned long pages, uint64_t *memory) 277 { 278 u64 len = pages << EFI_PAGE_SHIFT; 279 efi_status_t r = EFI_SUCCESS; 280 uint64_t addr; 281 282 switch (type) { 283 case 0: 284 /* Any page */ 285 addr = efi_find_free_memory(len, gd->start_addr_sp); 286 if (!addr) { 287 r = EFI_NOT_FOUND; 288 break; 289 } 290 break; 291 case 1: 292 /* Max address */ 293 addr = efi_find_free_memory(len, *memory); 294 if (!addr) { 295 r = EFI_NOT_FOUND; 296 break; 297 } 298 break; 299 case 2: 300 /* Exact address, reserve it. The addr is already in *memory. */ 301 addr = *memory; 302 break; 303 default: 304 /* UEFI doesn't specify other allocation types */ 305 r = EFI_INVALID_PARAMETER; 306 break; 307 } 308 309 if (r == EFI_SUCCESS) { 310 uint64_t ret; 311 312 /* Reserve that map in our memory maps */ 313 ret = efi_add_memory_map(addr, pages, memory_type, true); 314 if (ret == addr) { 315 *memory = addr; 316 } else { 317 /* Map would overlap, bail out */ 318 r = EFI_OUT_OF_RESOURCES; 319 } 320 } 321 322 return r; 323 } 324 325 void *efi_alloc(uint64_t len, int memory_type) 326 { 327 uint64_t ret = 0; 328 uint64_t pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT; 329 efi_status_t r; 330 331 r = efi_allocate_pages(0, memory_type, pages, &ret); 332 if (r == EFI_SUCCESS) 333 return (void*)(uintptr_t)ret; 334 335 return NULL; 336 } 337 338 efi_status_t efi_free_pages(uint64_t memory, unsigned long pages) 339 { 340 uint64_t r = 0; 341 342 r = efi_add_memory_map(memory, pages, EFI_CONVENTIONAL_MEMORY, false); 343 /* Merging of adjacent free regions is missing */ 344 345 if (r == memory) 346 return EFI_SUCCESS; 347 348 return EFI_NOT_FOUND; 349 } 350 351 efi_status_t efi_allocate_pool(int pool_type, unsigned long size, 352 void **buffer) 353 { 354 efi_status_t r; 355 efi_physical_addr_t t; 356 u64 num_pages = (size + sizeof(u64) + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT; 357 358 if (size == 0) { 359 *buffer = NULL; 360 return EFI_SUCCESS; 361 } 362 363 r = efi_allocate_pages(0, pool_type, num_pages, &t); 364 365 if (r == EFI_SUCCESS) { 366 struct efi_pool_allocation *alloc = (void *)(uintptr_t)t; 367 alloc->num_pages = num_pages; 368 *buffer = alloc->data; 369 } 370 371 return r; 372 } 373 374 efi_status_t efi_free_pool(void *buffer) 375 { 376 efi_status_t r; 377 struct efi_pool_allocation *alloc; 378 379 alloc = container_of(buffer, struct efi_pool_allocation, data); 380 /* Sanity check, was the supplied address returned by allocate_pool */ 381 assert(((uintptr_t)alloc & EFI_PAGE_MASK) == 0); 382 383 r = efi_free_pages((uintptr_t)alloc, alloc->num_pages); 384 385 return r; 386 } 387 388 efi_status_t efi_get_memory_map(unsigned long *memory_map_size, 389 struct efi_mem_desc *memory_map, 390 unsigned long *map_key, 391 unsigned long *descriptor_size, 392 uint32_t *descriptor_version) 393 { 394 ulong map_size = 0; 395 int map_entries = 0; 396 struct list_head *lhandle; 397 unsigned long provided_map_size = *memory_map_size; 398 399 list_for_each(lhandle, &efi_mem) 400 map_entries++; 401 402 map_size = map_entries * sizeof(struct efi_mem_desc); 403 404 *memory_map_size = map_size; 405 406 if (descriptor_size) 407 *descriptor_size = sizeof(struct efi_mem_desc); 408 409 if (descriptor_version) 410 *descriptor_version = EFI_MEMORY_DESCRIPTOR_VERSION; 411 412 if (provided_map_size < map_size) 413 return EFI_BUFFER_TOO_SMALL; 414 415 /* Copy list into array */ 416 if (memory_map) { 417 /* Return the list in ascending order */ 418 memory_map = &memory_map[map_entries - 1]; 419 list_for_each(lhandle, &efi_mem) { 420 struct efi_mem_list *lmem; 421 422 lmem = list_entry(lhandle, struct efi_mem_list, link); 423 *memory_map = lmem->desc; 424 memory_map--; 425 } 426 } 427 428 return EFI_SUCCESS; 429 } 430 431 int efi_memory_init(void) 432 { 433 unsigned long runtime_start, runtime_end, runtime_pages; 434 unsigned long uboot_start, uboot_pages; 435 unsigned long uboot_stack_size = 16 * 1024 * 1024; 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 /* Add U-Boot */ 450 uboot_start = (gd->start_addr_sp - uboot_stack_size) & ~EFI_PAGE_MASK; 451 uboot_pages = (gd->ram_top - uboot_start) >> EFI_PAGE_SHIFT; 452 efi_add_memory_map(uboot_start, uboot_pages, EFI_LOADER_DATA, false); 453 454 /* Add Runtime Services */ 455 runtime_start = (ulong)&__efi_runtime_start & ~EFI_PAGE_MASK; 456 runtime_end = (ulong)&__efi_runtime_stop; 457 runtime_end = (runtime_end + EFI_PAGE_MASK) & ~EFI_PAGE_MASK; 458 runtime_pages = (runtime_end - runtime_start) >> EFI_PAGE_SHIFT; 459 efi_add_memory_map(runtime_start, runtime_pages, 460 EFI_RUNTIME_SERVICES_CODE, false); 461 462 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER 463 /* Request a 32bit 64MB bounce buffer region */ 464 uint64_t efi_bounce_buffer_addr = 0xffffffff; 465 466 if (efi_allocate_pages(1, EFI_LOADER_DATA, 467 (64 * 1024 * 1024) >> EFI_PAGE_SHIFT, 468 &efi_bounce_buffer_addr) != EFI_SUCCESS) 469 return -1; 470 471 efi_bounce_buffer = (void*)(uintptr_t)efi_bounce_buffer_addr; 472 #endif 473 474 return 0; 475 } 476