1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  EFI application memory management
4  *
5  *  Copyright (c) 2016 Alexander Graf
6  */
7 
8 #define LOG_CATEGORY LOGC_EFI
9 
10 #include <common.h>
11 #include <efi_loader.h>
12 #include <init.h>
13 #include <log.h>
14 #include <malloc.h>
15 #include <mapmem.h>
16 #include <watchdog.h>
17 #include <asm/cache.h>
18 #include <asm/global_data.h>
19 #include <linux/list_sort.h>
20 #include <linux/sizes.h>
21 
22 DECLARE_GLOBAL_DATA_PTR;
23 
24 /* Magic number identifying memory allocated from pool */
25 #define EFI_ALLOC_POOL_MAGIC 0x1fe67ddf6491caa2
26 
27 efi_uintn_t efi_memory_map_key;
28 
29 struct efi_mem_list {
30 	struct list_head link;
31 	struct efi_mem_desc desc;
32 };
33 
34 #define EFI_CARVE_NO_OVERLAP		-1
35 #define EFI_CARVE_LOOP_AGAIN		-2
36 #define EFI_CARVE_OVERLAPS_NONRAM	-3
37 
38 /* This list contains all memory map items */
39 static LIST_HEAD(efi_mem);
40 
41 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
42 void *efi_bounce_buffer;
43 #endif
44 
45 /**
46  * struct efi_pool_allocation - memory block allocated from pool
47  *
48  * @num_pages:	number of pages allocated
49  * @checksum:	checksum
50  * @data:	allocated pool memory
51  *
52  * U-Boot services each UEFI AllocatePool() request as a separate
53  * (multiple) page allocation. We have to track the number of pages
54  * to be able to free the correct amount later.
55  *
56  * The checksum calculated in function checksum() is used in FreePool() to avoid
57  * freeing memory not allocated by AllocatePool() and duplicate freeing.
58  *
59  * EFI requires 8 byte alignment for pool allocations, so we can
60  * prepend each allocation with these header fields.
61  */
62 struct efi_pool_allocation {
63 	u64 num_pages;
64 	u64 checksum;
65 	char data[] __aligned(ARCH_DMA_MINALIGN);
66 };
67 
68 /**
69  * checksum() - calculate checksum for memory allocated from pool
70  *
71  * @alloc:	allocation header
72  * Return:	checksum, always non-zero
73  */
checksum(struct efi_pool_allocation * alloc)74 static u64 checksum(struct efi_pool_allocation *alloc)
75 {
76 	u64 addr = (uintptr_t)alloc;
77 	u64 ret = (addr >> 32) ^ (addr << 32) ^ alloc->num_pages ^
78 		  EFI_ALLOC_POOL_MAGIC;
79 	if (!ret)
80 		++ret;
81 	return ret;
82 }
83 
84 /**
85  * efi_mem_cmp() - comparator function for sorting memory map
86  *
87  * Sorts the memory list from highest address to lowest address
88  *
89  * When allocating memory we should always start from the highest
90  * address chunk, so sort the memory list such that the first list
91  * iterator gets the highest address and goes lower from there.
92  *
93  * @priv:	unused
94  * @a:		first memory area
95  * @b:		second memory area
96  * Return:	1 if @a is before @b, -1 if @b is before @a, 0 if equal
97  */
efi_mem_cmp(void * priv,struct list_head * a,struct list_head * b)98 static int efi_mem_cmp(void *priv, struct list_head *a, struct list_head *b)
99 {
100 	struct efi_mem_list *mema = list_entry(a, struct efi_mem_list, link);
101 	struct efi_mem_list *memb = list_entry(b, struct efi_mem_list, link);
102 
103 	if (mema->desc.physical_start == memb->desc.physical_start)
104 		return 0;
105 	else if (mema->desc.physical_start < memb->desc.physical_start)
106 		return 1;
107 	else
108 		return -1;
109 }
110 
111 /**
112  * desc_get_end() - get end address of memory area
113  *
114  * @desc:	memory descriptor
115  * Return:	end address + 1
116  */
desc_get_end(struct efi_mem_desc * desc)117 static uint64_t desc_get_end(struct efi_mem_desc *desc)
118 {
119 	return desc->physical_start + (desc->num_pages << EFI_PAGE_SHIFT);
120 }
121 
122 /**
123  * efi_mem_sort() - sort memory map
124  *
125  * Sort the memory map and then try to merge adjacent memory areas.
126  */
efi_mem_sort(void)127 static void efi_mem_sort(void)
128 {
129 	struct list_head *lhandle;
130 	struct efi_mem_list *prevmem = NULL;
131 	bool merge_again = true;
132 
133 	list_sort(NULL, &efi_mem, efi_mem_cmp);
134 
135 	/* Now merge entries that can be merged */
136 	while (merge_again) {
137 		merge_again = false;
138 		list_for_each(lhandle, &efi_mem) {
139 			struct efi_mem_list *lmem;
140 			struct efi_mem_desc *prev = &prevmem->desc;
141 			struct efi_mem_desc *cur;
142 			uint64_t pages;
143 
144 			lmem = list_entry(lhandle, struct efi_mem_list, link);
145 			if (!prevmem) {
146 				prevmem = lmem;
147 				continue;
148 			}
149 
150 			cur = &lmem->desc;
151 
152 			if ((desc_get_end(cur) == prev->physical_start) &&
153 			    (prev->type == cur->type) &&
154 			    (prev->attribute == cur->attribute)) {
155 				/* There is an existing map before, reuse it */
156 				pages = cur->num_pages;
157 				prev->num_pages += pages;
158 				prev->physical_start -= pages << EFI_PAGE_SHIFT;
159 				prev->virtual_start -= pages << EFI_PAGE_SHIFT;
160 				list_del(&lmem->link);
161 				free(lmem);
162 
163 				merge_again = true;
164 				break;
165 			}
166 
167 			prevmem = lmem;
168 		}
169 	}
170 }
171 
172 /**
173  * efi_mem_carve_out() - unmap memory region
174  *
175  * @map:		memory map
176  * @carve_desc:		memory region to unmap
177  * @overlap_only_ram:	the carved out region may only overlap RAM
178  * Return:		the number of overlapping pages which have been
179  *			removed from the map,
180  *			EFI_CARVE_NO_OVERLAP, if the regions don't overlap,
181  *			EFI_CARVE_OVERLAPS_NONRAM, if the carve and map overlap,
182  *			and the map contains anything but free ram
183  *			(only when overlap_only_ram is true),
184  *			EFI_CARVE_LOOP_AGAIN, if the mapping list should be
185  *			traversed again, as it has been altered.
186  *
187  * Unmaps all memory occupied by the carve_desc region from the list entry
188  * pointed to by map.
189  *
190  * In case of EFI_CARVE_OVERLAPS_NONRAM it is the callers responsibility
191  * to re-add the already carved out pages to the mapping.
192  */
efi_mem_carve_out(struct efi_mem_list * map,struct efi_mem_desc * carve_desc,bool overlap_only_ram)193 static s64 efi_mem_carve_out(struct efi_mem_list *map,
194 			     struct efi_mem_desc *carve_desc,
195 			     bool overlap_only_ram)
196 {
197 	struct efi_mem_list *newmap;
198 	struct efi_mem_desc *map_desc = &map->desc;
199 	uint64_t map_start = map_desc->physical_start;
200 	uint64_t map_end = map_start + (map_desc->num_pages << EFI_PAGE_SHIFT);
201 	uint64_t carve_start = carve_desc->physical_start;
202 	uint64_t carve_end = carve_start +
203 			     (carve_desc->num_pages << EFI_PAGE_SHIFT);
204 
205 	/* check whether we're overlapping */
206 	if ((carve_end <= map_start) || (carve_start >= map_end))
207 		return EFI_CARVE_NO_OVERLAP;
208 
209 	/* We're overlapping with non-RAM, warn the caller if desired */
210 	if (overlap_only_ram && (map_desc->type != EFI_CONVENTIONAL_MEMORY))
211 		return EFI_CARVE_OVERLAPS_NONRAM;
212 
213 	/* Sanitize carve_start and carve_end to lie within our bounds */
214 	carve_start = max(carve_start, map_start);
215 	carve_end = min(carve_end, map_end);
216 
217 	/* Carving at the beginning of our map? Just move it! */
218 	if (carve_start == map_start) {
219 		if (map_end == carve_end) {
220 			/* Full overlap, just remove map */
221 			list_del(&map->link);
222 			free(map);
223 		} else {
224 			map->desc.physical_start = carve_end;
225 			map->desc.virtual_start = carve_end;
226 			map->desc.num_pages = (map_end - carve_end)
227 					      >> EFI_PAGE_SHIFT;
228 		}
229 
230 		return (carve_end - carve_start) >> EFI_PAGE_SHIFT;
231 	}
232 
233 	/*
234 	 * Overlapping maps, just split the list map at carve_start,
235 	 * it will get moved or removed in the next iteration.
236 	 *
237 	 * [ map_desc |__carve_start__| newmap ]
238 	 */
239 
240 	/* Create a new map from [ carve_start ... map_end ] */
241 	newmap = calloc(1, sizeof(*newmap));
242 	newmap->desc = map->desc;
243 	newmap->desc.physical_start = carve_start;
244 	newmap->desc.virtual_start = carve_start;
245 	newmap->desc.num_pages = (map_end - carve_start) >> EFI_PAGE_SHIFT;
246 	/* Insert before current entry (descending address order) */
247 	list_add_tail(&newmap->link, &map->link);
248 
249 	/* Shrink the map to [ map_start ... carve_start ] */
250 	map_desc->num_pages = (carve_start - map_start) >> EFI_PAGE_SHIFT;
251 
252 	return EFI_CARVE_LOOP_AGAIN;
253 }
254 
255 /**
256  * efi_add_memory_map_pg() - add pages to the memory map
257  *
258  * @start:		start address, must be a multiple of EFI_PAGE_SIZE
259  * @pages:		number of pages to add
260  * @memory_type:	type of memory added
261  * @overlap_only_ram:	region may only overlap RAM
262  * Return:		status code
263  */
efi_add_memory_map_pg(u64 start,u64 pages,int memory_type,bool overlap_only_ram)264 static efi_status_t efi_add_memory_map_pg(u64 start, u64 pages,
265 					  int memory_type,
266 					  bool overlap_only_ram)
267 {
268 	struct list_head *lhandle;
269 	struct efi_mem_list *newlist;
270 	bool carve_again;
271 	uint64_t carved_pages = 0;
272 	struct efi_event *evt;
273 
274 	EFI_PRINT("%s: 0x%llx 0x%llx %d %s\n", __func__,
275 		  start, pages, memory_type, overlap_only_ram ? "yes" : "no");
276 
277 	if (memory_type >= EFI_MAX_MEMORY_TYPE)
278 		return EFI_INVALID_PARAMETER;
279 
280 	if (!pages)
281 		return EFI_SUCCESS;
282 
283 	++efi_memory_map_key;
284 	newlist = calloc(1, sizeof(*newlist));
285 	newlist->desc.type = memory_type;
286 	newlist->desc.physical_start = start;
287 	newlist->desc.virtual_start = start;
288 	newlist->desc.num_pages = pages;
289 
290 	switch (memory_type) {
291 	case EFI_RUNTIME_SERVICES_CODE:
292 	case EFI_RUNTIME_SERVICES_DATA:
293 		newlist->desc.attribute = EFI_MEMORY_WB | EFI_MEMORY_RUNTIME;
294 		break;
295 	case EFI_MMAP_IO:
296 		newlist->desc.attribute = EFI_MEMORY_RUNTIME;
297 		break;
298 	default:
299 		newlist->desc.attribute = EFI_MEMORY_WB;
300 		break;
301 	}
302 
303 	/* Add our new map */
304 	do {
305 		carve_again = false;
306 		list_for_each(lhandle, &efi_mem) {
307 			struct efi_mem_list *lmem;
308 			s64 r;
309 
310 			lmem = list_entry(lhandle, struct efi_mem_list, link);
311 			r = efi_mem_carve_out(lmem, &newlist->desc,
312 					      overlap_only_ram);
313 			switch (r) {
314 			case EFI_CARVE_OVERLAPS_NONRAM:
315 				/*
316 				 * The user requested to only have RAM overlaps,
317 				 * but we hit a non-RAM region. Error out.
318 				 */
319 				return EFI_NO_MAPPING;
320 			case EFI_CARVE_NO_OVERLAP:
321 				/* Just ignore this list entry */
322 				break;
323 			case EFI_CARVE_LOOP_AGAIN:
324 				/*
325 				 * We split an entry, but need to loop through
326 				 * the list again to actually carve it.
327 				 */
328 				carve_again = true;
329 				break;
330 			default:
331 				/* We carved a number of pages */
332 				carved_pages += r;
333 				carve_again = true;
334 				break;
335 			}
336 
337 			if (carve_again) {
338 				/* The list changed, we need to start over */
339 				break;
340 			}
341 		}
342 	} while (carve_again);
343 
344 	if (overlap_only_ram && (carved_pages != pages)) {
345 		/*
346 		 * The payload wanted to have RAM overlaps, but we overlapped
347 		 * with an unallocated region. Error out.
348 		 */
349 		return EFI_NO_MAPPING;
350 	}
351 
352 	/* Add our new map */
353         list_add_tail(&newlist->link, &efi_mem);
354 
355 	/* And make sure memory is listed in descending order */
356 	efi_mem_sort();
357 
358 	/* Notify that the memory map was changed */
359 	list_for_each_entry(evt, &efi_events, link) {
360 		if (evt->group &&
361 		    !guidcmp(evt->group,
362 			     &efi_guid_event_group_memory_map_change)) {
363 			efi_signal_event(evt);
364 			break;
365 		}
366 	}
367 
368 	return EFI_SUCCESS;
369 }
370 
371 /**
372  * efi_add_memory_map() - add memory area to the memory map
373  *
374  * @start:		start address of the memory area
375  * @size:		length in bytes of the memory area
376  * @memory_type:	type of memory added
377  *
378  * Return:		status code
379  *
380  * This function automatically aligns the start and size of the memory area
381  * to EFI_PAGE_SIZE.
382  */
efi_add_memory_map(u64 start,u64 size,int memory_type)383 efi_status_t efi_add_memory_map(u64 start, u64 size, int memory_type)
384 {
385 	u64 pages;
386 
387 	pages = efi_size_in_pages(size + (start & EFI_PAGE_MASK));
388 	start &= ~EFI_PAGE_MASK;
389 
390 	return efi_add_memory_map_pg(start, pages, memory_type, false);
391 }
392 
393 /**
394  * efi_check_allocated() - validate address to be freed
395  *
396  * Check that the address is within allocated memory:
397  *
398  * * The address must be in a range of the memory map.
399  * * The address may not point to EFI_CONVENTIONAL_MEMORY.
400  *
401  * Page alignment is not checked as this is not a requirement of
402  * efi_free_pool().
403  *
404  * @addr:		address of page to be freed
405  * @must_be_allocated:	return success if the page is allocated
406  * Return:		status code
407  */
efi_check_allocated(u64 addr,bool must_be_allocated)408 static efi_status_t efi_check_allocated(u64 addr, bool must_be_allocated)
409 {
410 	struct efi_mem_list *item;
411 
412 	list_for_each_entry(item, &efi_mem, link) {
413 		u64 start = item->desc.physical_start;
414 		u64 end = start + (item->desc.num_pages << EFI_PAGE_SHIFT);
415 
416 		if (addr >= start && addr < end) {
417 			if (must_be_allocated ^
418 			    (item->desc.type == EFI_CONVENTIONAL_MEMORY))
419 				return EFI_SUCCESS;
420 			else
421 				return EFI_NOT_FOUND;
422 		}
423 	}
424 
425 	return EFI_NOT_FOUND;
426 }
427 
428 /**
429  * efi_find_free_memory() - find free memory pages
430  *
431  * @len:	size of memory area needed
432  * @max_addr:	highest address to allocate
433  * Return:	pointer to free memory area or 0
434  */
efi_find_free_memory(uint64_t len,uint64_t max_addr)435 static uint64_t efi_find_free_memory(uint64_t len, uint64_t max_addr)
436 {
437 	struct list_head *lhandle;
438 
439 	/*
440 	 * Prealign input max address, so we simplify our matching
441 	 * logic below and can just reuse it as return pointer.
442 	 */
443 	max_addr &= ~EFI_PAGE_MASK;
444 
445 	list_for_each(lhandle, &efi_mem) {
446 		struct efi_mem_list *lmem = list_entry(lhandle,
447 			struct efi_mem_list, link);
448 		struct efi_mem_desc *desc = &lmem->desc;
449 		uint64_t desc_len = desc->num_pages << EFI_PAGE_SHIFT;
450 		uint64_t desc_end = desc->physical_start + desc_len;
451 		uint64_t curmax = min(max_addr, desc_end);
452 		uint64_t ret = curmax - len;
453 
454 		/* We only take memory from free RAM */
455 		if (desc->type != EFI_CONVENTIONAL_MEMORY)
456 			continue;
457 
458 		/* Out of bounds for max_addr */
459 		if ((ret + len) > max_addr)
460 			continue;
461 
462 		/* Out of bounds for upper map limit */
463 		if ((ret + len) > desc_end)
464 			continue;
465 
466 		/* Out of bounds for lower map limit */
467 		if (ret < desc->physical_start)
468 			continue;
469 
470 		/* Return the highest address in this map within bounds */
471 		return ret;
472 	}
473 
474 	return 0;
475 }
476 
477 /**
478  * efi_allocate_pages - allocate memory pages
479  *
480  * @type:		type of allocation to be performed
481  * @memory_type:	usage type of the allocated memory
482  * @pages:		number of pages to be allocated
483  * @memory:		allocated memory
484  * Return:		status code
485  */
efi_allocate_pages(enum efi_allocate_type type,enum efi_memory_type memory_type,efi_uintn_t pages,uint64_t * memory)486 efi_status_t efi_allocate_pages(enum efi_allocate_type type,
487 				enum efi_memory_type memory_type,
488 				efi_uintn_t pages, uint64_t *memory)
489 {
490 	u64 len = pages << EFI_PAGE_SHIFT;
491 	efi_status_t ret;
492 	uint64_t addr;
493 
494 	/* Check import parameters */
495 	if (memory_type >= EFI_PERSISTENT_MEMORY_TYPE &&
496 	    memory_type <= 0x6FFFFFFF)
497 		return EFI_INVALID_PARAMETER;
498 	if (!memory)
499 		return EFI_INVALID_PARAMETER;
500 
501 	switch (type) {
502 	case EFI_ALLOCATE_ANY_PAGES:
503 		/* Any page */
504 		addr = efi_find_free_memory(len, -1ULL);
505 		if (!addr)
506 			return EFI_OUT_OF_RESOURCES;
507 		break;
508 	case EFI_ALLOCATE_MAX_ADDRESS:
509 		/* Max address */
510 		addr = efi_find_free_memory(len, *memory);
511 		if (!addr)
512 			return EFI_OUT_OF_RESOURCES;
513 		break;
514 	case EFI_ALLOCATE_ADDRESS:
515 		if (*memory & EFI_PAGE_MASK)
516 			return EFI_NOT_FOUND;
517 		/* Exact address, reserve it. The addr is already in *memory. */
518 		ret = efi_check_allocated(*memory, false);
519 		if (ret != EFI_SUCCESS)
520 			return EFI_NOT_FOUND;
521 		addr = *memory;
522 		break;
523 	default:
524 		/* UEFI doesn't specify other allocation types */
525 		return EFI_INVALID_PARAMETER;
526 	}
527 
528 	/* Reserve that map in our memory maps */
529 	ret = efi_add_memory_map_pg(addr, pages, memory_type, true);
530 	if (ret != EFI_SUCCESS)
531 		/* Map would overlap, bail out */
532 		return  EFI_OUT_OF_RESOURCES;
533 
534 	*memory = addr;
535 
536 	return EFI_SUCCESS;
537 }
538 
539 /**
540  * efi_free_pages() - free memory pages
541  *
542  * @memory:	start of the memory area to be freed
543  * @pages:	number of pages to be freed
544  * Return:	status code
545  */
efi_free_pages(uint64_t memory,efi_uintn_t pages)546 efi_status_t efi_free_pages(uint64_t memory, efi_uintn_t pages)
547 {
548 	efi_status_t ret;
549 
550 	ret = efi_check_allocated(memory, true);
551 	if (ret != EFI_SUCCESS)
552 		return ret;
553 
554 	/* Sanity check */
555 	if (!memory || (memory & EFI_PAGE_MASK) || !pages) {
556 		printf("%s: illegal free 0x%llx, 0x%zx\n", __func__,
557 		       memory, pages);
558 		return EFI_INVALID_PARAMETER;
559 	}
560 
561 	ret = efi_add_memory_map_pg(memory, pages, EFI_CONVENTIONAL_MEMORY,
562 				    false);
563 	if (ret != EFI_SUCCESS)
564 		return EFI_NOT_FOUND;
565 
566 	return ret;
567 }
568 
569 /**
570  * efi_alloc_aligned_pages() - allocate aligned memory pages
571  *
572  * @len:		len in bytes
573  * @memory_type:	usage type of the allocated memory
574  * @align:		alignment in bytes
575  * Return:		aligned memory or NULL
576  */
efi_alloc_aligned_pages(u64 len,int memory_type,size_t align)577 void *efi_alloc_aligned_pages(u64 len, int memory_type, size_t align)
578 {
579 	u64 req_pages = efi_size_in_pages(len);
580 	u64 true_pages = req_pages + efi_size_in_pages(align) - 1;
581 	u64 free_pages;
582 	u64 aligned_mem;
583 	efi_status_t r;
584 	u64 mem;
585 
586 	/* align must be zero or a power of two */
587 	if (align & (align - 1))
588 		return NULL;
589 
590 	/* Check for overflow */
591 	if (true_pages < req_pages)
592 		return NULL;
593 
594 	if (align < EFI_PAGE_SIZE) {
595 		r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, memory_type,
596 				       req_pages, &mem);
597 		return (r == EFI_SUCCESS) ? (void *)(uintptr_t)mem : NULL;
598 	}
599 
600 	r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, memory_type,
601 			       true_pages, &mem);
602 	if (r != EFI_SUCCESS)
603 		return NULL;
604 
605 	aligned_mem = ALIGN(mem, align);
606 	/* Free pages before alignment */
607 	free_pages = efi_size_in_pages(aligned_mem - mem);
608 	if (free_pages)
609 		efi_free_pages(mem, free_pages);
610 
611 	/* Free trailing pages */
612 	free_pages = true_pages - (req_pages + free_pages);
613 	if (free_pages) {
614 		mem = aligned_mem + req_pages * EFI_PAGE_SIZE;
615 		efi_free_pages(mem, free_pages);
616 	}
617 
618 	return (void *)(uintptr_t)aligned_mem;
619 }
620 
621 /**
622  * efi_allocate_pool - allocate memory from pool
623  *
624  * @pool_type:	type of the pool from which memory is to be allocated
625  * @size:	number of bytes to be allocated
626  * @buffer:	allocated memory
627  * Return:	status code
628  */
efi_allocate_pool(enum efi_memory_type pool_type,efi_uintn_t size,void ** buffer)629 efi_status_t efi_allocate_pool(enum efi_memory_type pool_type, efi_uintn_t size, void **buffer)
630 {
631 	efi_status_t r;
632 	u64 addr;
633 	struct efi_pool_allocation *alloc;
634 	u64 num_pages = efi_size_in_pages(size +
635 					  sizeof(struct efi_pool_allocation));
636 
637 	if (!buffer)
638 		return EFI_INVALID_PARAMETER;
639 
640 	if (size == 0) {
641 		*buffer = NULL;
642 		return EFI_SUCCESS;
643 	}
644 
645 	r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, pool_type, num_pages,
646 			       &addr);
647 	if (r == EFI_SUCCESS) {
648 		alloc = (struct efi_pool_allocation *)(uintptr_t)addr;
649 		alloc->num_pages = num_pages;
650 		alloc->checksum = checksum(alloc);
651 		*buffer = alloc->data;
652 	}
653 
654 	return r;
655 }
656 
657 /**
658  * efi_alloc() - allocate boot services data pool memory
659  *
660  * Allocate memory from pool and zero it out.
661  *
662  * @size:	number of bytes to allocate
663  * Return:	pointer to allocated memory or NULL
664  */
efi_alloc(size_t size)665 void *efi_alloc(size_t size)
666 {
667 	void *buf;
668 
669 	if (efi_allocate_pool(EFI_BOOT_SERVICES_DATA, size, &buf) !=
670 	    EFI_SUCCESS) {
671 		log_err("out of memory");
672 		return NULL;
673 	}
674 	memset(buf, 0, size);
675 
676 	return buf;
677 }
678 
679 /**
680  * efi_free_pool() - free memory from pool
681  *
682  * @buffer:	start of memory to be freed
683  * Return:	status code
684  */
efi_free_pool(void * buffer)685 efi_status_t efi_free_pool(void *buffer)
686 {
687 	efi_status_t ret;
688 	struct efi_pool_allocation *alloc;
689 
690 	if (!buffer)
691 		return EFI_INVALID_PARAMETER;
692 
693 	ret = efi_check_allocated((uintptr_t)buffer, true);
694 	if (ret != EFI_SUCCESS)
695 		return ret;
696 
697 	alloc = container_of(buffer, struct efi_pool_allocation, data);
698 
699 	/* Check that this memory was allocated by efi_allocate_pool() */
700 	if (((uintptr_t)alloc & EFI_PAGE_MASK) ||
701 	    alloc->checksum != checksum(alloc)) {
702 		printf("%s: illegal free 0x%p\n", __func__, buffer);
703 		return EFI_INVALID_PARAMETER;
704 	}
705 	/* Avoid double free */
706 	alloc->checksum = 0;
707 
708 	ret = efi_free_pages((uintptr_t)alloc, alloc->num_pages);
709 
710 	return ret;
711 }
712 
713 /**
714  * efi_get_memory_map() - get map describing memory usage.
715  *
716  * @memory_map_size:	on entry the size, in bytes, of the memory map buffer,
717  *			on exit the size of the copied memory map
718  * @memory_map:		buffer to which the memory map is written
719  * @map_key:		key for the memory map
720  * @descriptor_size:	size of an individual memory descriptor
721  * @descriptor_version:	version number of the memory descriptor structure
722  * Return:		status code
723  */
efi_get_memory_map(efi_uintn_t * memory_map_size,struct efi_mem_desc * memory_map,efi_uintn_t * map_key,efi_uintn_t * descriptor_size,uint32_t * descriptor_version)724 efi_status_t efi_get_memory_map(efi_uintn_t *memory_map_size,
725 				struct efi_mem_desc *memory_map,
726 				efi_uintn_t *map_key,
727 				efi_uintn_t *descriptor_size,
728 				uint32_t *descriptor_version)
729 {
730 	efi_uintn_t map_size = 0;
731 	int map_entries = 0;
732 	struct list_head *lhandle;
733 	efi_uintn_t provided_map_size;
734 
735 	if (!memory_map_size)
736 		return EFI_INVALID_PARAMETER;
737 
738 	provided_map_size = *memory_map_size;
739 
740 	list_for_each(lhandle, &efi_mem)
741 		map_entries++;
742 
743 	map_size = map_entries * sizeof(struct efi_mem_desc);
744 
745 	*memory_map_size = map_size;
746 
747 	if (descriptor_size)
748 		*descriptor_size = sizeof(struct efi_mem_desc);
749 
750 	if (descriptor_version)
751 		*descriptor_version = EFI_MEMORY_DESCRIPTOR_VERSION;
752 
753 	if (provided_map_size < map_size)
754 		return EFI_BUFFER_TOO_SMALL;
755 
756 	if (!memory_map)
757 		return EFI_INVALID_PARAMETER;
758 
759 	/* Copy list into array */
760 	/* Return the list in ascending order */
761 	memory_map = &memory_map[map_entries - 1];
762 	list_for_each(lhandle, &efi_mem) {
763 		struct efi_mem_list *lmem;
764 
765 		lmem = list_entry(lhandle, struct efi_mem_list, link);
766 		*memory_map = lmem->desc;
767 		memory_map--;
768 	}
769 
770 	if (map_key)
771 		*map_key = efi_memory_map_key;
772 
773 	return EFI_SUCCESS;
774 }
775 
776 /**
777  * efi_get_memory_map_alloc() - allocate map describing memory usage
778  *
779  * The caller is responsible for calling FreePool() if the call succeeds.
780  *
781  * @map_size:		size of the memory map
782  * @memory_map:		buffer to which the memory map is written
783  * Return:		status code
784  */
efi_get_memory_map_alloc(efi_uintn_t * map_size,struct efi_mem_desc ** memory_map)785 efi_status_t efi_get_memory_map_alloc(efi_uintn_t *map_size,
786 				      struct efi_mem_desc **memory_map)
787 {
788 	efi_status_t ret;
789 
790 	*memory_map = NULL;
791 	*map_size = 0;
792 	ret = efi_get_memory_map(map_size, *memory_map, NULL, NULL, NULL);
793 	if (ret == EFI_BUFFER_TOO_SMALL) {
794 		*map_size += sizeof(struct efi_mem_desc); /* for the map */
795 		ret = efi_allocate_pool(EFI_BOOT_SERVICES_DATA, *map_size,
796 					(void **)memory_map);
797 		if (ret != EFI_SUCCESS)
798 			return ret;
799 		ret = efi_get_memory_map(map_size, *memory_map,
800 					 NULL, NULL, NULL);
801 		if (ret != EFI_SUCCESS) {
802 			efi_free_pool(*memory_map);
803 			*memory_map = NULL;
804 		}
805 	}
806 
807 	return ret;
808 }
809 
810 /**
811  * efi_add_conventional_memory_map() - add a RAM memory area to the map
812  *
813  * @ram_start:		start address of a RAM memory area
814  * @ram_end:		end address of a RAM memory area
815  * @ram_top:		max address to be used as conventional memory
816  * Return:		status code
817  */
efi_add_conventional_memory_map(u64 ram_start,u64 ram_end,u64 ram_top)818 efi_status_t efi_add_conventional_memory_map(u64 ram_start, u64 ram_end,
819 					     u64 ram_top)
820 {
821 	u64 pages;
822 
823 	/* Remove partial pages */
824 	ram_end &= ~EFI_PAGE_MASK;
825 	ram_start = (ram_start + EFI_PAGE_MASK) & ~EFI_PAGE_MASK;
826 
827 	if (ram_end <= ram_start) {
828 		/* Invalid mapping */
829 		return EFI_INVALID_PARAMETER;
830 	}
831 
832 	pages = (ram_end - ram_start) >> EFI_PAGE_SHIFT;
833 
834 	efi_add_memory_map_pg(ram_start, pages,
835 			      EFI_CONVENTIONAL_MEMORY, false);
836 
837 	/*
838 	 * Boards may indicate to the U-Boot memory core that they
839 	 * can not support memory above ram_top. Let's honor this
840 	 * in the efi_loader subsystem too by declaring any memory
841 	 * above ram_top as "already occupied by firmware".
842 	 */
843 	if (ram_top < ram_start) {
844 		/* ram_top is before this region, reserve all */
845 		efi_add_memory_map_pg(ram_start, pages,
846 				      EFI_BOOT_SERVICES_DATA, true);
847 	} else if (ram_top < ram_end) {
848 		/* ram_top is inside this region, reserve parts */
849 		pages = (ram_end - ram_top) >> EFI_PAGE_SHIFT;
850 
851 		efi_add_memory_map_pg(ram_top, pages,
852 				      EFI_BOOT_SERVICES_DATA, true);
853 	}
854 
855 	return EFI_SUCCESS;
856 }
857 
858 /**
859  * efi_add_known_memory() - add memory banks to map
860  *
861  * This function may be overridden for specific architectures.
862  */
efi_add_known_memory(void)863 __weak void efi_add_known_memory(void)
864 {
865 	u64 ram_top = board_get_usable_ram_top(0) & ~EFI_PAGE_MASK;
866 	int i;
867 
868 	/*
869 	 * ram_top is just outside mapped memory. So use an offset of one for
870 	 * mapping the sandbox address.
871 	 */
872 	ram_top = (uintptr_t)map_sysmem(ram_top - 1, 0) + 1;
873 
874 	/* Fix for 32bit targets with ram_top at 4G */
875 	if (!ram_top)
876 		ram_top = 0x100000000ULL;
877 
878 	/* Add RAM */
879 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
880 		u64 ram_end, ram_start;
881 
882 		ram_start = (uintptr_t)map_sysmem(gd->bd->bi_dram[i].start, 0);
883 		ram_end = ram_start + gd->bd->bi_dram[i].size;
884 
885 		efi_add_conventional_memory_map(ram_start, ram_end, ram_top);
886 	}
887 }
888 
889 /**
890  * add_u_boot_and_runtime() - add U-Boot code to memory map
891  *
892  * Add memory regions for U-Boot's memory and for the runtime services code.
893  */
add_u_boot_and_runtime(void)894 static void add_u_boot_and_runtime(void)
895 {
896 	unsigned long runtime_start, runtime_end, runtime_pages;
897 	unsigned long runtime_mask = EFI_PAGE_MASK;
898 	unsigned long uboot_start, uboot_pages;
899 	unsigned long uboot_stack_size = CONFIG_STACK_SIZE;
900 
901 	/* Add U-Boot */
902 	uboot_start = ((uintptr_t)map_sysmem(gd->start_addr_sp, 0) -
903 		       uboot_stack_size) & ~EFI_PAGE_MASK;
904 	uboot_pages = ((uintptr_t)map_sysmem(gd->ram_top - 1, 0) -
905 		       uboot_start + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
906 	efi_add_memory_map_pg(uboot_start, uboot_pages, EFI_BOOT_SERVICES_CODE,
907 			      false);
908 
909 #if defined(__aarch64__)
910 	/*
911 	 * Runtime Services must be 64KiB aligned according to the
912 	 * "AArch64 Platforms" section in the UEFI spec (2.7+).
913 	 */
914 
915 	runtime_mask = SZ_64K - 1;
916 #endif
917 
918 	/*
919 	 * Add Runtime Services. We mark surrounding boottime code as runtime as
920 	 * well to fulfill the runtime alignment constraints but avoid padding.
921 	 */
922 	runtime_start = (ulong)&__efi_runtime_start & ~runtime_mask;
923 	runtime_end = (ulong)&__efi_runtime_stop;
924 	runtime_end = (runtime_end + runtime_mask) & ~runtime_mask;
925 	runtime_pages = (runtime_end - runtime_start) >> EFI_PAGE_SHIFT;
926 	efi_add_memory_map_pg(runtime_start, runtime_pages,
927 			      EFI_RUNTIME_SERVICES_CODE, false);
928 }
929 
efi_memory_init(void)930 int efi_memory_init(void)
931 {
932 	efi_add_known_memory();
933 
934 	add_u_boot_and_runtime();
935 
936 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
937 	/* Request a 32bit 64MB bounce buffer region */
938 	uint64_t efi_bounce_buffer_addr = 0xffffffff;
939 
940 	if (efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS, EFI_BOOT_SERVICES_DATA,
941 			       (64 * 1024 * 1024) >> EFI_PAGE_SHIFT,
942 			       &efi_bounce_buffer_addr) != EFI_SUCCESS)
943 		return -1;
944 
945 	efi_bounce_buffer = (void*)(uintptr_t)efi_bounce_buffer_addr;
946 #endif
947 
948 	return 0;
949 }
950