1 // SPDX-License-Identifier: GPL-2.0+
3 * EFI application memory management
5 * Copyright (c) 2016 Alexander Graf
9 #include <efi_loader.h>
13 #include <linux/list_sort.h>
15 DECLARE_GLOBAL_DATA_PTR;
17 efi_uintn_t efi_memory_map_key;
20 struct list_head link;
21 struct efi_mem_desc desc;
24 #define EFI_CARVE_NO_OVERLAP -1
25 #define EFI_CARVE_LOOP_AGAIN -2
26 #define EFI_CARVE_OVERLAPS_NONRAM -3
28 /* This list contains all memory map items */
31 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
32 void *efi_bounce_buffer;
36 * U-Boot services each EFI AllocatePool request as a separate
37 * (multiple) page allocation. We have to track the number of pages
38 * to be able to free the correct amount later.
39 * EFI requires 8 byte alignment for pool allocations, so we can
40 * prepend each allocation with an 64 bit header tracking the
41 * allocation size, and hand out the remainder to the caller.
43 struct efi_pool_allocation {
45 char data[] __aligned(ARCH_DMA_MINALIGN);
49 * Sorts the memory list from highest address to lowest address
51 * When allocating memory we should always start from the highest
52 * address chunk, so sort the memory list such that the first list
53 * iterator gets the highest address and goes lower from there.
55 static int efi_mem_cmp(void *priv, struct list_head *a, struct list_head *b)
57 struct efi_mem_list *mema = list_entry(a, struct efi_mem_list, link);
58 struct efi_mem_list *memb = list_entry(b, struct efi_mem_list, link);
60 if (mema->desc.physical_start == memb->desc.physical_start)
62 else if (mema->desc.physical_start < memb->desc.physical_start)
68 static void efi_mem_sort(void)
70 list_sort(NULL, &efi_mem, efi_mem_cmp);
73 /** efi_mem_carve_out - unmap memory region
76 * @carve_desc: memory region to unmap
77 * @overlap_only_ram: the carved out region may only overlap RAM
78 * Return Value: the number of overlapping pages which have been
79 * removed from the map,
80 * EFI_CARVE_NO_OVERLAP, if the regions don't overlap,
81 * EFI_CARVE_OVERLAPS_NONRAM, if the carve and map overlap,
82 * and the map contains anything but free ram
83 * (only when overlap_only_ram is true),
84 * EFI_CARVE_LOOP_AGAIN, if the mapping list should be
85 * traversed again, as it has been altered.
87 * Unmaps all memory occupied by the carve_desc region from the list entry
90 * In case of EFI_CARVE_OVERLAPS_NONRAM it is the callers responsibility
91 * to re-add the already carved out pages to the mapping.
93 static s64 efi_mem_carve_out(struct efi_mem_list *map,
94 struct efi_mem_desc *carve_desc,
95 bool overlap_only_ram)
97 struct efi_mem_list *newmap;
98 struct efi_mem_desc *map_desc = &map->desc;
99 uint64_t map_start = map_desc->physical_start;
100 uint64_t map_end = map_start + (map_desc->num_pages << EFI_PAGE_SHIFT);
101 uint64_t carve_start = carve_desc->physical_start;
102 uint64_t carve_end = carve_start +
103 (carve_desc->num_pages << EFI_PAGE_SHIFT);
105 /* check whether we're overlapping */
106 if ((carve_end <= map_start) || (carve_start >= map_end))
107 return EFI_CARVE_NO_OVERLAP;
109 /* We're overlapping with non-RAM, warn the caller if desired */
110 if (overlap_only_ram && (map_desc->type != EFI_CONVENTIONAL_MEMORY))
111 return EFI_CARVE_OVERLAPS_NONRAM;
113 /* Sanitize carve_start and carve_end to lie within our bounds */
114 carve_start = max(carve_start, map_start);
115 carve_end = min(carve_end, map_end);
117 /* Carving at the beginning of our map? Just move it! */
118 if (carve_start == map_start) {
119 if (map_end == carve_end) {
120 /* Full overlap, just remove map */
121 list_del(&map->link);
124 map->desc.physical_start = carve_end;
125 map->desc.num_pages = (map_end - carve_end)
129 return (carve_end - carve_start) >> EFI_PAGE_SHIFT;
133 * Overlapping maps, just split the list map at carve_start,
134 * it will get moved or removed in the next iteration.
136 * [ map_desc |__carve_start__| newmap ]
139 /* Create a new map from [ carve_start ... map_end ] */
140 newmap = calloc(1, sizeof(*newmap));
141 newmap->desc = map->desc;
142 newmap->desc.physical_start = carve_start;
143 newmap->desc.num_pages = (map_end - carve_start) >> EFI_PAGE_SHIFT;
144 /* Insert before current entry (descending address order) */
145 list_add_tail(&newmap->link, &map->link);
147 /* Shrink the map to [ map_start ... carve_start ] */
148 map_desc->num_pages = (carve_start - map_start) >> EFI_PAGE_SHIFT;
150 return EFI_CARVE_LOOP_AGAIN;
153 uint64_t efi_add_memory_map(uint64_t start, uint64_t pages, int memory_type,
154 bool overlap_only_ram)
156 struct list_head *lhandle;
157 struct efi_mem_list *newlist;
159 uint64_t carved_pages = 0;
161 debug("%s: 0x%llx 0x%llx %d %s\n", __func__,
162 start, pages, memory_type, overlap_only_ram ? "yes" : "no");
164 if (memory_type >= EFI_MAX_MEMORY_TYPE)
165 return EFI_INVALID_PARAMETER;
170 ++efi_memory_map_key;
171 newlist = calloc(1, sizeof(*newlist));
172 newlist->desc.type = memory_type;
173 newlist->desc.physical_start = start;
174 newlist->desc.virtual_start = start;
175 newlist->desc.num_pages = pages;
177 switch (memory_type) {
178 case EFI_RUNTIME_SERVICES_CODE:
179 case EFI_RUNTIME_SERVICES_DATA:
180 newlist->desc.attribute = EFI_MEMORY_WB | EFI_MEMORY_RUNTIME;
183 newlist->desc.attribute = EFI_MEMORY_RUNTIME;
186 newlist->desc.attribute = EFI_MEMORY_WB;
190 /* Add our new map */
193 list_for_each(lhandle, &efi_mem) {
194 struct efi_mem_list *lmem;
197 lmem = list_entry(lhandle, struct efi_mem_list, link);
198 r = efi_mem_carve_out(lmem, &newlist->desc,
201 case EFI_CARVE_OVERLAPS_NONRAM:
203 * The user requested to only have RAM overlaps,
204 * but we hit a non-RAM region. Error out.
207 case EFI_CARVE_NO_OVERLAP:
208 /* Just ignore this list entry */
210 case EFI_CARVE_LOOP_AGAIN:
212 * We split an entry, but need to loop through
213 * the list again to actually carve it.
218 /* We carved a number of pages */
225 /* The list changed, we need to start over */
229 } while (carve_again);
231 if (overlap_only_ram && (carved_pages != pages)) {
233 * The payload wanted to have RAM overlaps, but we overlapped
234 * with an unallocated region. Error out.
239 /* Add our new map */
240 list_add_tail(&newlist->link, &efi_mem);
242 /* And make sure memory is listed in descending order */
248 static uint64_t efi_find_free_memory(uint64_t len, uint64_t max_addr)
250 struct list_head *lhandle;
252 list_for_each(lhandle, &efi_mem) {
253 struct efi_mem_list *lmem = list_entry(lhandle,
254 struct efi_mem_list, link);
255 struct efi_mem_desc *desc = &lmem->desc;
256 uint64_t desc_len = desc->num_pages << EFI_PAGE_SHIFT;
257 uint64_t desc_end = desc->physical_start + desc_len;
258 uint64_t curmax = min(max_addr, desc_end);
259 uint64_t ret = curmax - len;
261 /* We only take memory from free RAM */
262 if (desc->type != EFI_CONVENTIONAL_MEMORY)
265 /* Out of bounds for max_addr */
266 if ((ret + len) > max_addr)
269 /* Out of bounds for upper map limit */
270 if ((ret + len) > desc_end)
273 /* Out of bounds for lower map limit */
274 if (ret < desc->physical_start)
277 /* Return the highest address in this map within bounds */
285 * Allocate memory pages.
287 * @type type of allocation to be performed
288 * @memory_type usage type of the allocated memory
289 * @pages number of pages to be allocated
290 * @memory allocated memory
291 * @return status code
293 efi_status_t efi_allocate_pages(int type, int memory_type,
294 efi_uintn_t pages, uint64_t *memory)
296 u64 len = pages << EFI_PAGE_SHIFT;
297 efi_status_t r = EFI_SUCCESS;
301 return EFI_INVALID_PARAMETER;
304 case EFI_ALLOCATE_ANY_PAGES:
306 addr = efi_find_free_memory(len, -1ULL);
312 case EFI_ALLOCATE_MAX_ADDRESS:
314 addr = efi_find_free_memory(len, *memory);
320 case EFI_ALLOCATE_ADDRESS:
321 /* Exact address, reserve it. The addr is already in *memory. */
325 /* UEFI doesn't specify other allocation types */
326 r = EFI_INVALID_PARAMETER;
330 if (r == EFI_SUCCESS) {
333 /* Reserve that map in our memory maps */
334 ret = efi_add_memory_map(addr, pages, memory_type, true);
336 *memory = (uintptr_t)map_sysmem(addr, len);
338 /* Map would overlap, bail out */
339 r = EFI_OUT_OF_RESOURCES;
346 void *efi_alloc(uint64_t len, int memory_type)
349 uint64_t pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
352 r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, memory_type, pages,
354 if (r == EFI_SUCCESS)
355 return (void*)(uintptr_t)ret;
363 * @memory start of the memory area to be freed
364 * @pages number of pages to be freed
365 * @return status code
367 efi_status_t efi_free_pages(uint64_t memory, efi_uintn_t pages)
370 uint64_t addr = map_to_sysmem((void *)(uintptr_t)memory);
372 r = efi_add_memory_map(addr, pages, EFI_CONVENTIONAL_MEMORY, false);
373 /* Merging of adjacent free regions is missing */
378 return EFI_NOT_FOUND;
382 * Allocate memory from pool.
384 * @pool_type type of the pool from which memory is to be allocated
385 * @size number of bytes to be allocated
386 * @buffer allocated memory
387 * @return status code
389 efi_status_t efi_allocate_pool(int pool_type, efi_uintn_t size, void **buffer)
392 struct efi_pool_allocation *alloc;
393 u64 num_pages = (size + sizeof(struct efi_pool_allocation) +
394 EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
397 return EFI_INVALID_PARAMETER;
404 r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, pool_type, num_pages,
407 if (r == EFI_SUCCESS) {
408 alloc->num_pages = num_pages;
409 *buffer = alloc->data;
416 * Free memory from pool.
418 * @buffer start of memory to be freed
419 * @return status code
421 efi_status_t efi_free_pool(void *buffer)
424 struct efi_pool_allocation *alloc;
427 return EFI_INVALID_PARAMETER;
429 alloc = container_of(buffer, struct efi_pool_allocation, data);
430 /* Sanity check, was the supplied address returned by allocate_pool */
431 assert(((uintptr_t)alloc & EFI_PAGE_MASK) == 0);
433 r = efi_free_pages((uintptr_t)alloc, alloc->num_pages);
439 * Get map describing memory usage.
441 * @memory_map_size on entry the size, in bytes, of the memory map buffer,
442 * on exit the size of the copied memory map
443 * @memory_map buffer to which the memory map is written
444 * @map_key key for the memory map
445 * @descriptor_size size of an individual memory descriptor
446 * @descriptor_version version number of the memory descriptor structure
447 * @return status code
449 efi_status_t efi_get_memory_map(efi_uintn_t *memory_map_size,
450 struct efi_mem_desc *memory_map,
451 efi_uintn_t *map_key,
452 efi_uintn_t *descriptor_size,
453 uint32_t *descriptor_version)
455 efi_uintn_t map_size = 0;
457 struct list_head *lhandle;
458 efi_uintn_t provided_map_size;
460 if (!memory_map_size)
461 return EFI_INVALID_PARAMETER;
463 provided_map_size = *memory_map_size;
465 list_for_each(lhandle, &efi_mem)
468 map_size = map_entries * sizeof(struct efi_mem_desc);
470 *memory_map_size = map_size;
472 if (provided_map_size < map_size)
473 return EFI_BUFFER_TOO_SMALL;
476 return EFI_INVALID_PARAMETER;
479 *descriptor_size = sizeof(struct efi_mem_desc);
481 if (descriptor_version)
482 *descriptor_version = EFI_MEMORY_DESCRIPTOR_VERSION;
484 /* Copy list into array */
485 /* Return the list in ascending order */
486 memory_map = &memory_map[map_entries - 1];
487 list_for_each(lhandle, &efi_mem) {
488 struct efi_mem_list *lmem;
490 lmem = list_entry(lhandle, struct efi_mem_list, link);
491 *memory_map = lmem->desc;
496 *map_key = efi_memory_map_key;
501 __weak void efi_add_known_memory(void)
506 for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
507 u64 ram_start = gd->bd->bi_dram[i].start;
508 u64 ram_size = gd->bd->bi_dram[i].size;
509 u64 start = (ram_start + EFI_PAGE_MASK) & ~EFI_PAGE_MASK;
510 u64 pages = (ram_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
512 efi_add_memory_map(start, pages, EFI_CONVENTIONAL_MEMORY,
517 /* Add memory regions for U-Boot's memory and for the runtime services code */
518 static void add_u_boot_and_runtime(void)
520 unsigned long runtime_start, runtime_end, runtime_pages;
521 unsigned long uboot_start, uboot_pages;
522 unsigned long uboot_stack_size = 16 * 1024 * 1024;
525 uboot_start = (gd->start_addr_sp - uboot_stack_size) & ~EFI_PAGE_MASK;
526 uboot_pages = (gd->ram_top - uboot_start) >> EFI_PAGE_SHIFT;
527 efi_add_memory_map(uboot_start, uboot_pages, EFI_LOADER_DATA, false);
529 /* Add Runtime Services */
530 runtime_start = (ulong)&__efi_runtime_start & ~EFI_PAGE_MASK;
531 runtime_end = (ulong)&__efi_runtime_stop;
532 runtime_end = (runtime_end + EFI_PAGE_MASK) & ~EFI_PAGE_MASK;
533 runtime_pages = (runtime_end - runtime_start) >> EFI_PAGE_SHIFT;
534 efi_add_memory_map(runtime_start, runtime_pages,
535 EFI_RUNTIME_SERVICES_CODE, false);
538 int efi_memory_init(void)
540 efi_add_known_memory();
542 if (!IS_ENABLED(CONFIG_SANDBOX))
543 add_u_boot_and_runtime();
545 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
546 /* Request a 32bit 64MB bounce buffer region */
547 uint64_t efi_bounce_buffer_addr = 0xffffffff;
549 if (efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS, EFI_LOADER_DATA,
550 (64 * 1024 * 1024) >> EFI_PAGE_SHIFT,
551 &efi_bounce_buffer_addr) != EFI_SUCCESS)
554 efi_bounce_buffer = (void*)(uintptr_t)efi_bounce_buffer_addr;