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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Low level x86 E820 memory map handling functions.
4 *
5 * The firmware and bootloader passes us the "E820 table", which is the primary
6 * physical memory layout description available about x86 systems.
7 *
8 * The kernel takes the E820 memory layout and optionally modifies it with
9 * quirks and other tweaks, and feeds that into the generic Linux memory
10 * allocation code routines via a platform independent interface (memblock, etc.).
11 */
12#include <linux/crash_dump.h>
13#include <linux/memblock.h>
14#include <linux/suspend.h>
15#include <linux/acpi.h>
16#include <linux/firmware-map.h>
17#include <linux/sort.h>
18#include <linux/memory_hotplug.h>
19
20#include <asm/e820/api.h>
21#include <asm/setup.h>
22
23/*
24 * We organize the E820 table into three main data structures:
25 *
26 * - 'e820_table_firmware': the original firmware version passed to us by the
27 * bootloader - not modified by the kernel. It is composed of two parts:
28 * the first 128 E820 memory entries in boot_params.e820_table and the remaining
29 * (if any) entries of the SETUP_E820_EXT nodes. We use this to:
30 *
31 * - inform the user about the firmware's notion of memory layout
32 * via /sys/firmware/memmap
33 *
34 * - the hibernation code uses it to generate a kernel-independent MD5
35 * fingerprint of the physical memory layout of a system.
36 *
37 * - 'e820_table_kexec': a slightly modified (by the kernel) firmware version
38 * passed to us by the bootloader - the major difference between
39 * e820_table_firmware[] and this one is that, the latter marks the setup_data
40 * list created by the EFI boot stub as reserved, so that kexec can reuse the
41 * setup_data information in the second kernel. Besides, e820_table_kexec[]
42 * might also be modified by the kexec itself to fake a mptable.
43 * We use this to:
44 *
45 * - kexec, which is a bootloader in disguise, uses the original E820
46 * layout to pass to the kexec-ed kernel. This way the original kernel
47 * can have a restricted E820 map while the kexec()-ed kexec-kernel
48 * can have access to full memory - etc.
49 *
50 * - 'e820_table': this is the main E820 table that is massaged by the
51 * low level x86 platform code, or modified by boot parameters, before
52 * passed on to higher level MM layers.
53 *
54 * Once the E820 map has been converted to the standard Linux memory layout
55 * information its role stops - modifying it has no effect and does not get
56 * re-propagated. So itsmain role is a temporary bootstrap storage of firmware
57 * specific memory layout data during early bootup.
58 */
59static struct e820_table e820_table_init __initdata;
60static struct e820_table e820_table_kexec_init __initdata;
61static struct e820_table e820_table_firmware_init __initdata;
62
63struct e820_table *e820_table __refdata = &e820_table_init;
64struct e820_table *e820_table_kexec __refdata = &e820_table_kexec_init;
65struct e820_table *e820_table_firmware __refdata = &e820_table_firmware_init;
66
67/* For PCI or other memory-mapped resources */
68unsigned long pci_mem_start = 0xaeedbabe;
69#ifdef CONFIG_PCI
70EXPORT_SYMBOL(pci_mem_start);
71#endif
72
73/*
74 * This function checks if any part of the range <start,end> is mapped
75 * with type.
76 */
77static bool _e820__mapped_any(struct e820_table *table,
78 u64 start, u64 end, enum e820_type type)
79{
80 int i;
81
82 for (i = 0; i < table->nr_entries; i++) {
83 struct e820_entry *entry = &table->entries[i];
84
85 if (type && entry->type != type)
86 continue;
87 if (entry->addr >= end || entry->addr + entry->size <= start)
88 continue;
89 return true;
90 }
91 return false;
92}
93
94bool e820__mapped_raw_any(u64 start, u64 end, enum e820_type type)
95{
96 return _e820__mapped_any(e820_table_firmware, start, end, type);
97}
98EXPORT_SYMBOL_GPL(e820__mapped_raw_any);
99
100bool e820__mapped_any(u64 start, u64 end, enum e820_type type)
101{
102 return _e820__mapped_any(e820_table, start, end, type);
103}
104EXPORT_SYMBOL_GPL(e820__mapped_any);
105
106/*
107 * This function checks if the entire <start,end> range is mapped with 'type'.
108 *
109 * Note: this function only works correctly once the E820 table is sorted and
110 * not-overlapping (at least for the range specified), which is the case normally.
111 */
112static struct e820_entry *__e820__mapped_all(u64 start, u64 end,
113 enum e820_type type)
114{
115 int i;
116
117 for (i = 0; i < e820_table->nr_entries; i++) {
118 struct e820_entry *entry = &e820_table->entries[i];
119
120 if (type && entry->type != type)
121 continue;
122
123 /* Is the region (part) in overlap with the current region? */
124 if (entry->addr >= end || entry->addr + entry->size <= start)
125 continue;
126
127 /*
128 * If the region is at the beginning of <start,end> we move
129 * 'start' to the end of the region since it's ok until there
130 */
131 if (entry->addr <= start)
132 start = entry->addr + entry->size;
133
134 /*
135 * If 'start' is now at or beyond 'end', we're done, full
136 * coverage of the desired range exists:
137 */
138 if (start >= end)
139 return entry;
140 }
141
142 return NULL;
143}
144
145/*
146 * This function checks if the entire range <start,end> is mapped with type.
147 */
148bool __init e820__mapped_all(u64 start, u64 end, enum e820_type type)
149{
150 return __e820__mapped_all(start, end, type);
151}
152
153/*
154 * This function returns the type associated with the range <start,end>.
155 */
156int e820__get_entry_type(u64 start, u64 end)
157{
158 struct e820_entry *entry = __e820__mapped_all(start, end, 0);
159
160 return entry ? entry->type : -EINVAL;
161}
162
163/*
164 * Add a memory region to the kernel E820 map.
165 */
166static void __init __e820__range_add(struct e820_table *table, u64 start, u64 size, enum e820_type type)
167{
168 int x = table->nr_entries;
169
170 if (x >= ARRAY_SIZE(table->entries)) {
171 pr_err("too many entries; ignoring [mem %#010llx-%#010llx]\n",
172 start, start + size - 1);
173 return;
174 }
175
176 table->entries[x].addr = start;
177 table->entries[x].size = size;
178 table->entries[x].type = type;
179 table->nr_entries++;
180}
181
182void __init e820__range_add(u64 start, u64 size, enum e820_type type)
183{
184 __e820__range_add(e820_table, start, size, type);
185}
186
187static void __init e820_print_type(enum e820_type type)
188{
189 switch (type) {
190 case E820_TYPE_RAM: /* Fall through: */
191 case E820_TYPE_RESERVED_KERN: pr_cont("usable"); break;
192 case E820_TYPE_RESERVED: pr_cont("reserved"); break;
193 case E820_TYPE_ACPI: pr_cont("ACPI data"); break;
194 case E820_TYPE_NVS: pr_cont("ACPI NVS"); break;
195 case E820_TYPE_UNUSABLE: pr_cont("unusable"); break;
196 case E820_TYPE_PMEM: /* Fall through: */
197 case E820_TYPE_PRAM: pr_cont("persistent (type %u)", type); break;
198 default: pr_cont("type %u", type); break;
199 }
200}
201
202void __init e820__print_table(char *who)
203{
204 int i;
205
206 for (i = 0; i < e820_table->nr_entries; i++) {
207 pr_info("%s: [mem %#018Lx-%#018Lx] ",
208 who,
209 e820_table->entries[i].addr,
210 e820_table->entries[i].addr + e820_table->entries[i].size - 1);
211
212 e820_print_type(e820_table->entries[i].type);
213 pr_cont("\n");
214 }
215}
216
217/*
218 * Sanitize an E820 map.
219 *
220 * Some E820 layouts include overlapping entries. The following
221 * replaces the original E820 map with a new one, removing overlaps,
222 * and resolving conflicting memory types in favor of highest
223 * numbered type.
224 *
225 * The input parameter 'entries' points to an array of 'struct
226 * e820_entry' which on entry has elements in the range [0, *nr_entries)
227 * valid, and which has space for up to max_nr_entries entries.
228 * On return, the resulting sanitized E820 map entries will be in
229 * overwritten in the same location, starting at 'entries'.
230 *
231 * The integer pointed to by nr_entries must be valid on entry (the
232 * current number of valid entries located at 'entries'). If the
233 * sanitizing succeeds the *nr_entries will be updated with the new
234 * number of valid entries (something no more than max_nr_entries).
235 *
236 * The return value from e820__update_table() is zero if it
237 * successfully 'sanitized' the map entries passed in, and is -1
238 * if it did nothing, which can happen if either of (1) it was
239 * only passed one map entry, or (2) any of the input map entries
240 * were invalid (start + size < start, meaning that the size was
241 * so big the described memory range wrapped around through zero.)
242 *
243 * Visually we're performing the following
244 * (1,2,3,4 = memory types)...
245 *
246 * Sample memory map (w/overlaps):
247 * ____22__________________
248 * ______________________4_
249 * ____1111________________
250 * _44_____________________
251 * 11111111________________
252 * ____________________33__
253 * ___________44___________
254 * __________33333_________
255 * ______________22________
256 * ___________________2222_
257 * _________111111111______
258 * _____________________11_
259 * _________________4______
260 *
261 * Sanitized equivalent (no overlap):
262 * 1_______________________
263 * _44_____________________
264 * ___1____________________
265 * ____22__________________
266 * ______11________________
267 * _________1______________
268 * __________3_____________
269 * ___________44___________
270 * _____________33_________
271 * _______________2________
272 * ________________1_______
273 * _________________4______
274 * ___________________2____
275 * ____________________33__
276 * ______________________4_
277 */
278struct change_member {
279 /* Pointer to the original entry: */
280 struct e820_entry *entry;
281 /* Address for this change point: */
282 unsigned long long addr;
283};
284
285static struct change_member change_point_list[2*E820_MAX_ENTRIES] __initdata;
286static struct change_member *change_point[2*E820_MAX_ENTRIES] __initdata;
287static struct e820_entry *overlap_list[E820_MAX_ENTRIES] __initdata;
288static struct e820_entry new_entries[E820_MAX_ENTRIES] __initdata;
289
290static int __init cpcompare(const void *a, const void *b)
291{
292 struct change_member * const *app = a, * const *bpp = b;
293 const struct change_member *ap = *app, *bp = *bpp;
294
295 /*
296 * Inputs are pointers to two elements of change_point[]. If their
297 * addresses are not equal, their difference dominates. If the addresses
298 * are equal, then consider one that represents the end of its region
299 * to be greater than one that does not.
300 */
301 if (ap->addr != bp->addr)
302 return ap->addr > bp->addr ? 1 : -1;
303
304 return (ap->addr != ap->entry->addr) - (bp->addr != bp->entry->addr);
305}
306
307int __init e820__update_table(struct e820_table *table)
308{
309 struct e820_entry *entries = table->entries;
310 u32 max_nr_entries = ARRAY_SIZE(table->entries);
311 enum e820_type current_type, last_type;
312 unsigned long long last_addr;
313 u32 new_nr_entries, overlap_entries;
314 u32 i, chg_idx, chg_nr;
315
316 /* If there's only one memory region, don't bother: */
317 if (table->nr_entries < 2)
318 return -1;
319
320 BUG_ON(table->nr_entries > max_nr_entries);
321
322 /* Bail out if we find any unreasonable addresses in the map: */
323 for (i = 0; i < table->nr_entries; i++) {
324 if (entries[i].addr + entries[i].size < entries[i].addr)
325 return -1;
326 }
327
328 /* Create pointers for initial change-point information (for sorting): */
329 for (i = 0; i < 2 * table->nr_entries; i++)
330 change_point[i] = &change_point_list[i];
331
332 /*
333 * Record all known change-points (starting and ending addresses),
334 * omitting empty memory regions:
335 */
336 chg_idx = 0;
337 for (i = 0; i < table->nr_entries; i++) {
338 if (entries[i].size != 0) {
339 change_point[chg_idx]->addr = entries[i].addr;
340 change_point[chg_idx++]->entry = &entries[i];
341 change_point[chg_idx]->addr = entries[i].addr + entries[i].size;
342 change_point[chg_idx++]->entry = &entries[i];
343 }
344 }
345 chg_nr = chg_idx;
346
347 /* Sort change-point list by memory addresses (low -> high): */
348 sort(change_point, chg_nr, sizeof(*change_point), cpcompare, NULL);
349
350 /* Create a new memory map, removing overlaps: */
351 overlap_entries = 0; /* Number of entries in the overlap table */
352 new_nr_entries = 0; /* Index for creating new map entries */
353 last_type = 0; /* Start with undefined memory type */
354 last_addr = 0; /* Start with 0 as last starting address */
355
356 /* Loop through change-points, determining effect on the new map: */
357 for (chg_idx = 0; chg_idx < chg_nr; chg_idx++) {
358 /* Keep track of all overlapping entries */
359 if (change_point[chg_idx]->addr == change_point[chg_idx]->entry->addr) {
360 /* Add map entry to overlap list (> 1 entry implies an overlap) */
361 overlap_list[overlap_entries++] = change_point[chg_idx]->entry;
362 } else {
363 /* Remove entry from list (order independent, so swap with last): */
364 for (i = 0; i < overlap_entries; i++) {
365 if (overlap_list[i] == change_point[chg_idx]->entry)
366 overlap_list[i] = overlap_list[overlap_entries-1];
367 }
368 overlap_entries--;
369 }
370 /*
371 * If there are overlapping entries, decide which
372 * "type" to use (larger value takes precedence --
373 * 1=usable, 2,3,4,4+=unusable)
374 */
375 current_type = 0;
376 for (i = 0; i < overlap_entries; i++) {
377 if (overlap_list[i]->type > current_type)
378 current_type = overlap_list[i]->type;
379 }
380
381 /* Continue building up new map based on this information: */
382 if (current_type != last_type || current_type == E820_TYPE_PRAM) {
383 if (last_type != 0) {
384 new_entries[new_nr_entries].size = change_point[chg_idx]->addr - last_addr;
385 /* Move forward only if the new size was non-zero: */
386 if (new_entries[new_nr_entries].size != 0)
387 /* No more space left for new entries? */
388 if (++new_nr_entries >= max_nr_entries)
389 break;
390 }
391 if (current_type != 0) {
392 new_entries[new_nr_entries].addr = change_point[chg_idx]->addr;
393 new_entries[new_nr_entries].type = current_type;
394 last_addr = change_point[chg_idx]->addr;
395 }
396 last_type = current_type;
397 }
398 }
399
400 /* Copy the new entries into the original location: */
401 memcpy(entries, new_entries, new_nr_entries*sizeof(*entries));
402 table->nr_entries = new_nr_entries;
403
404 return 0;
405}
406
407static int __init __append_e820_table(struct boot_e820_entry *entries, u32 nr_entries)
408{
409 struct boot_e820_entry *entry = entries;
410
411 while (nr_entries) {
412 u64 start = entry->addr;
413 u64 size = entry->size;
414 u64 end = start + size - 1;
415 u32 type = entry->type;
416
417 /* Ignore the entry on 64-bit overflow: */
418 if (start > end && likely(size))
419 return -1;
420
421 e820__range_add(start, size, type);
422
423 entry++;
424 nr_entries--;
425 }
426 return 0;
427}
428
429/*
430 * Copy the BIOS E820 map into a safe place.
431 *
432 * Sanity-check it while we're at it..
433 *
434 * If we're lucky and live on a modern system, the setup code
435 * will have given us a memory map that we can use to properly
436 * set up memory. If we aren't, we'll fake a memory map.
437 */
438static int __init append_e820_table(struct boot_e820_entry *entries, u32 nr_entries)
439{
440 /* Only one memory region (or negative)? Ignore it */
441 if (nr_entries < 2)
442 return -1;
443
444 return __append_e820_table(entries, nr_entries);
445}
446
447static u64 __init
448__e820__range_update(struct e820_table *table, u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
449{
450 u64 end;
451 unsigned int i;
452 u64 real_updated_size = 0;
453
454 BUG_ON(old_type == new_type);
455
456 if (size > (ULLONG_MAX - start))
457 size = ULLONG_MAX - start;
458
459 end = start + size;
460 printk(KERN_DEBUG "e820: update [mem %#010Lx-%#010Lx] ", start, end - 1);
461 e820_print_type(old_type);
462 pr_cont(" ==> ");
463 e820_print_type(new_type);
464 pr_cont("\n");
465
466 for (i = 0; i < table->nr_entries; i++) {
467 struct e820_entry *entry = &table->entries[i];
468 u64 final_start, final_end;
469 u64 entry_end;
470
471 if (entry->type != old_type)
472 continue;
473
474 entry_end = entry->addr + entry->size;
475
476 /* Completely covered by new range? */
477 if (entry->addr >= start && entry_end <= end) {
478 entry->type = new_type;
479 real_updated_size += entry->size;
480 continue;
481 }
482
483 /* New range is completely covered? */
484 if (entry->addr < start && entry_end > end) {
485 __e820__range_add(table, start, size, new_type);
486 __e820__range_add(table, end, entry_end - end, entry->type);
487 entry->size = start - entry->addr;
488 real_updated_size += size;
489 continue;
490 }
491
492 /* Partially covered: */
493 final_start = max(start, entry->addr);
494 final_end = min(end, entry_end);
495 if (final_start >= final_end)
496 continue;
497
498 __e820__range_add(table, final_start, final_end - final_start, new_type);
499
500 real_updated_size += final_end - final_start;
501
502 /*
503 * Left range could be head or tail, so need to update
504 * its size first:
505 */
506 entry->size -= final_end - final_start;
507 if (entry->addr < final_start)
508 continue;
509
510 entry->addr = final_end;
511 }
512 return real_updated_size;
513}
514
515u64 __init e820__range_update(u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
516{
517 return __e820__range_update(e820_table, start, size, old_type, new_type);
518}
519
520static u64 __init e820__range_update_kexec(u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
521{
522 return __e820__range_update(e820_table_kexec, start, size, old_type, new_type);
523}
524
525/* Remove a range of memory from the E820 table: */
526u64 __init e820__range_remove(u64 start, u64 size, enum e820_type old_type, bool check_type)
527{
528 int i;
529 u64 end;
530 u64 real_removed_size = 0;
531
532 if (size > (ULLONG_MAX - start))
533 size = ULLONG_MAX - start;
534
535 end = start + size;
536 printk(KERN_DEBUG "e820: remove [mem %#010Lx-%#010Lx] ", start, end - 1);
537 if (check_type)
538 e820_print_type(old_type);
539 pr_cont("\n");
540
541 for (i = 0; i < e820_table->nr_entries; i++) {
542 struct e820_entry *entry = &e820_table->entries[i];
543 u64 final_start, final_end;
544 u64 entry_end;
545
546 if (check_type && entry->type != old_type)
547 continue;
548
549 entry_end = entry->addr + entry->size;
550
551 /* Completely covered? */
552 if (entry->addr >= start && entry_end <= end) {
553 real_removed_size += entry->size;
554 memset(entry, 0, sizeof(*entry));
555 continue;
556 }
557
558 /* Is the new range completely covered? */
559 if (entry->addr < start && entry_end > end) {
560 e820__range_add(end, entry_end - end, entry->type);
561 entry->size = start - entry->addr;
562 real_removed_size += size;
563 continue;
564 }
565
566 /* Partially covered: */
567 final_start = max(start, entry->addr);
568 final_end = min(end, entry_end);
569 if (final_start >= final_end)
570 continue;
571
572 real_removed_size += final_end - final_start;
573
574 /*
575 * Left range could be head or tail, so need to update
576 * the size first:
577 */
578 entry->size -= final_end - final_start;
579 if (entry->addr < final_start)
580 continue;
581
582 entry->addr = final_end;
583 }
584 return real_removed_size;
585}
586
587void __init e820__update_table_print(void)
588{
589 if (e820__update_table(e820_table))
590 return;
591
592 pr_info("modified physical RAM map:\n");
593 e820__print_table("modified");
594}
595
596static void __init e820__update_table_kexec(void)
597{
598 e820__update_table(e820_table_kexec);
599}
600
601#define MAX_GAP_END 0x100000000ull
602
603/*
604 * Search for a gap in the E820 memory space from 0 to MAX_GAP_END (4GB).
605 */
606static int __init e820_search_gap(unsigned long *gapstart, unsigned long *gapsize)
607{
608 unsigned long long last = MAX_GAP_END;
609 int i = e820_table->nr_entries;
610 int found = 0;
611
612 while (--i >= 0) {
613 unsigned long long start = e820_table->entries[i].addr;
614 unsigned long long end = start + e820_table->entries[i].size;
615
616 /*
617 * Since "last" is at most 4GB, we know we'll
618 * fit in 32 bits if this condition is true:
619 */
620 if (last > end) {
621 unsigned long gap = last - end;
622
623 if (gap >= *gapsize) {
624 *gapsize = gap;
625 *gapstart = end;
626 found = 1;
627 }
628 }
629 if (start < last)
630 last = start;
631 }
632 return found;
633}
634
635/*
636 * Search for the biggest gap in the low 32 bits of the E820
637 * memory space. We pass this space to the PCI subsystem, so
638 * that it can assign MMIO resources for hotplug or
639 * unconfigured devices in.
640 *
641 * Hopefully the BIOS let enough space left.
642 */
643__init void e820__setup_pci_gap(void)
644{
645 unsigned long gapstart, gapsize;
646 int found;
647
648 gapsize = 0x400000;
649 found = e820_search_gap(&gapstart, &gapsize);
650
651 if (!found) {
652#ifdef CONFIG_X86_64
653 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
654 pr_err("Cannot find an available gap in the 32-bit address range\n");
655 pr_err("PCI devices with unassigned 32-bit BARs may not work!\n");
656#else
657 gapstart = 0x10000000;
658#endif
659 }
660
661 /*
662 * e820__reserve_resources_late() protects stolen RAM already:
663 */
664 pci_mem_start = gapstart;
665
666 pr_info("[mem %#010lx-%#010lx] available for PCI devices\n",
667 gapstart, gapstart + gapsize - 1);
668}
669
670/*
671 * Called late during init, in free_initmem().
672 *
673 * Initial e820_table and e820_table_kexec are largish __initdata arrays.
674 *
675 * Copy them to a (usually much smaller) dynamically allocated area that is
676 * sized precisely after the number of e820 entries.
677 *
678 * This is done after we've performed all the fixes and tweaks to the tables.
679 * All functions which modify them are __init functions, which won't exist
680 * after free_initmem().
681 */
682__init void e820__reallocate_tables(void)
683{
684 struct e820_table *n;
685 int size;
686
687 size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table->nr_entries;
688 n = kmemdup(e820_table, size, GFP_KERNEL);
689 BUG_ON(!n);
690 e820_table = n;
691
692 size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_kexec->nr_entries;
693 n = kmemdup(e820_table_kexec, size, GFP_KERNEL);
694 BUG_ON(!n);
695 e820_table_kexec = n;
696
697 size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_firmware->nr_entries;
698 n = kmemdup(e820_table_firmware, size, GFP_KERNEL);
699 BUG_ON(!n);
700 e820_table_firmware = n;
701}
702
703/*
704 * Because of the small fixed size of struct boot_params, only the first
705 * 128 E820 memory entries are passed to the kernel via boot_params.e820_table,
706 * the remaining (if any) entries are passed via the SETUP_E820_EXT node of
707 * struct setup_data, which is parsed here.
708 */
709void __init e820__memory_setup_extended(u64 phys_addr, u32 data_len)
710{
711 int entries;
712 struct boot_e820_entry *extmap;
713 struct setup_data *sdata;
714
715 sdata = early_memremap(phys_addr, data_len);
716 entries = sdata->len / sizeof(*extmap);
717 extmap = (struct boot_e820_entry *)(sdata->data);
718
719 __append_e820_table(extmap, entries);
720 e820__update_table(e820_table);
721
722 memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec));
723 memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
724
725 early_memunmap(sdata, data_len);
726 pr_info("extended physical RAM map:\n");
727 e820__print_table("extended");
728}
729
730/*
731 * Find the ranges of physical addresses that do not correspond to
732 * E820 RAM areas and register the corresponding pages as 'nosave' for
733 * hibernation (32-bit) or software suspend and suspend to RAM (64-bit).
734 *
735 * This function requires the E820 map to be sorted and without any
736 * overlapping entries.
737 */
738void __init e820__register_nosave_regions(unsigned long limit_pfn)
739{
740 int i;
741 unsigned long pfn = 0;
742
743 for (i = 0; i < e820_table->nr_entries; i++) {
744 struct e820_entry *entry = &e820_table->entries[i];
745
746 if (pfn < PFN_UP(entry->addr))
747 register_nosave_region(pfn, PFN_UP(entry->addr));
748
749 pfn = PFN_DOWN(entry->addr + entry->size);
750
751 if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
752 register_nosave_region(PFN_UP(entry->addr), pfn);
753
754 if (pfn >= limit_pfn)
755 break;
756 }
757}
758
759#ifdef CONFIG_ACPI
760/*
761 * Register ACPI NVS memory regions, so that we can save/restore them during
762 * hibernation and the subsequent resume:
763 */
764static int __init e820__register_nvs_regions(void)
765{
766 int i;
767
768 for (i = 0; i < e820_table->nr_entries; i++) {
769 struct e820_entry *entry = &e820_table->entries[i];
770
771 if (entry->type == E820_TYPE_NVS)
772 acpi_nvs_register(entry->addr, entry->size);
773 }
774
775 return 0;
776}
777core_initcall(e820__register_nvs_regions);
778#endif
779
780/*
781 * Allocate the requested number of bytes with the requsted alignment
782 * and return (the physical address) to the caller. Also register this
783 * range in the 'kexec' E820 table as a reserved range.
784 *
785 * This allows kexec to fake a new mptable, as if it came from the real
786 * system.
787 */
788u64 __init e820__memblock_alloc_reserved(u64 size, u64 align)
789{
790 u64 addr;
791
792 addr = memblock_phys_alloc(size, align);
793 if (addr) {
794 e820__range_update_kexec(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED);
795 pr_info("update e820_table_kexec for e820__memblock_alloc_reserved()\n");
796 e820__update_table_kexec();
797 }
798
799 return addr;
800}
801
802#ifdef CONFIG_X86_32
803# ifdef CONFIG_X86_PAE
804# define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
805# else
806# define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
807# endif
808#else /* CONFIG_X86_32 */
809# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
810#endif
811
812/*
813 * Find the highest page frame number we have available
814 */
815static unsigned long __init e820_end_pfn(unsigned long limit_pfn, enum e820_type type)
816{
817 int i;
818 unsigned long last_pfn = 0;
819 unsigned long max_arch_pfn = MAX_ARCH_PFN;
820
821 for (i = 0; i < e820_table->nr_entries; i++) {
822 struct e820_entry *entry = &e820_table->entries[i];
823 unsigned long start_pfn;
824 unsigned long end_pfn;
825
826 if (entry->type != type)
827 continue;
828
829 start_pfn = entry->addr >> PAGE_SHIFT;
830 end_pfn = (entry->addr + entry->size) >> PAGE_SHIFT;
831
832 if (start_pfn >= limit_pfn)
833 continue;
834 if (end_pfn > limit_pfn) {
835 last_pfn = limit_pfn;
836 break;
837 }
838 if (end_pfn > last_pfn)
839 last_pfn = end_pfn;
840 }
841
842 if (last_pfn > max_arch_pfn)
843 last_pfn = max_arch_pfn;
844
845 pr_info("last_pfn = %#lx max_arch_pfn = %#lx\n",
846 last_pfn, max_arch_pfn);
847 return last_pfn;
848}
849
850unsigned long __init e820__end_of_ram_pfn(void)
851{
852 return e820_end_pfn(MAX_ARCH_PFN, E820_TYPE_RAM);
853}
854
855unsigned long __init e820__end_of_low_ram_pfn(void)
856{
857 return e820_end_pfn(1UL << (32 - PAGE_SHIFT), E820_TYPE_RAM);
858}
859
860static void __init early_panic(char *msg)
861{
862 early_printk(msg);
863 panic(msg);
864}
865
866static int userdef __initdata;
867
868/* The "mem=nopentium" boot option disables 4MB page tables on 32-bit kernels: */
869static int __init parse_memopt(char *p)
870{
871 u64 mem_size;
872
873 if (!p)
874 return -EINVAL;
875
876 if (!strcmp(p, "nopentium")) {
877#ifdef CONFIG_X86_32
878 setup_clear_cpu_cap(X86_FEATURE_PSE);
879 return 0;
880#else
881 pr_warn("mem=nopentium ignored! (only supported on x86_32)\n");
882 return -EINVAL;
883#endif
884 }
885
886 userdef = 1;
887 mem_size = memparse(p, &p);
888
889 /* Don't remove all memory when getting "mem={invalid}" parameter: */
890 if (mem_size == 0)
891 return -EINVAL;
892
893 e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
894
895#ifdef CONFIG_MEMORY_HOTPLUG
896 max_mem_size = mem_size;
897#endif
898
899 return 0;
900}
901early_param("mem", parse_memopt);
902
903static int __init parse_memmap_one(char *p)
904{
905 char *oldp;
906 u64 start_at, mem_size;
907
908 if (!p)
909 return -EINVAL;
910
911 if (!strncmp(p, "exactmap", 8)) {
912#ifdef CONFIG_CRASH_DUMP
913 /*
914 * If we are doing a crash dump, we still need to know
915 * the real memory size before the original memory map is
916 * reset.
917 */
918 saved_max_pfn = e820__end_of_ram_pfn();
919#endif
920 e820_table->nr_entries = 0;
921 userdef = 1;
922 return 0;
923 }
924
925 oldp = p;
926 mem_size = memparse(p, &p);
927 if (p == oldp)
928 return -EINVAL;
929
930 userdef = 1;
931 if (*p == '@') {
932 start_at = memparse(p+1, &p);
933 e820__range_add(start_at, mem_size, E820_TYPE_RAM);
934 } else if (*p == '#') {
935 start_at = memparse(p+1, &p);
936 e820__range_add(start_at, mem_size, E820_TYPE_ACPI);
937 } else if (*p == '$') {
938 start_at = memparse(p+1, &p);
939 e820__range_add(start_at, mem_size, E820_TYPE_RESERVED);
940 } else if (*p == '!') {
941 start_at = memparse(p+1, &p);
942 e820__range_add(start_at, mem_size, E820_TYPE_PRAM);
943 } else if (*p == '%') {
944 enum e820_type from = 0, to = 0;
945
946 start_at = memparse(p + 1, &p);
947 if (*p == '-')
948 from = simple_strtoull(p + 1, &p, 0);
949 if (*p == '+')
950 to = simple_strtoull(p + 1, &p, 0);
951 if (*p != '\0')
952 return -EINVAL;
953 if (from && to)
954 e820__range_update(start_at, mem_size, from, to);
955 else if (to)
956 e820__range_add(start_at, mem_size, to);
957 else if (from)
958 e820__range_remove(start_at, mem_size, from, 1);
959 else
960 e820__range_remove(start_at, mem_size, 0, 0);
961 } else {
962 e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
963 }
964
965 return *p == '\0' ? 0 : -EINVAL;
966}
967
968static int __init parse_memmap_opt(char *str)
969{
970 while (str) {
971 char *k = strchr(str, ',');
972
973 if (k)
974 *k++ = 0;
975
976 parse_memmap_one(str);
977 str = k;
978 }
979
980 return 0;
981}
982early_param("memmap", parse_memmap_opt);
983
984/*
985 * Reserve all entries from the bootloader's extensible data nodes list,
986 * because if present we are going to use it later on to fetch e820
987 * entries from it:
988 */
989void __init e820__reserve_setup_data(void)
990{
991 struct setup_data *data;
992 u64 pa_data;
993
994 pa_data = boot_params.hdr.setup_data;
995 if (!pa_data)
996 return;
997
998 while (pa_data) {
999 data = early_memremap(pa_data, sizeof(*data));
1000 e820__range_update(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
1001 e820__range_update_kexec(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
1002 pa_data = data->next;
1003 early_memunmap(data, sizeof(*data));
1004 }
1005
1006 e820__update_table(e820_table);
1007 e820__update_table(e820_table_kexec);
1008
1009 pr_info("extended physical RAM map:\n");
1010 e820__print_table("reserve setup_data");
1011}
1012
1013/*
1014 * Called after parse_early_param(), after early parameters (such as mem=)
1015 * have been processed, in which case we already have an E820 table filled in
1016 * via the parameter callback function(s), but it's not sorted and printed yet:
1017 */
1018void __init e820__finish_early_params(void)
1019{
1020 if (userdef) {
1021 if (e820__update_table(e820_table) < 0)
1022 early_panic("Invalid user supplied memory map");
1023
1024 pr_info("user-defined physical RAM map:\n");
1025 e820__print_table("user");
1026 }
1027}
1028
1029static const char *__init e820_type_to_string(struct e820_entry *entry)
1030{
1031 switch (entry->type) {
1032 case E820_TYPE_RESERVED_KERN: /* Fall-through: */
1033 case E820_TYPE_RAM: return "System RAM";
1034 case E820_TYPE_ACPI: return "ACPI Tables";
1035 case E820_TYPE_NVS: return "ACPI Non-volatile Storage";
1036 case E820_TYPE_UNUSABLE: return "Unusable memory";
1037 case E820_TYPE_PRAM: return "Persistent Memory (legacy)";
1038 case E820_TYPE_PMEM: return "Persistent Memory";
1039 case E820_TYPE_RESERVED: return "Reserved";
1040 default: return "Unknown E820 type";
1041 }
1042}
1043
1044static unsigned long __init e820_type_to_iomem_type(struct e820_entry *entry)
1045{
1046 switch (entry->type) {
1047 case E820_TYPE_RESERVED_KERN: /* Fall-through: */
1048 case E820_TYPE_RAM: return IORESOURCE_SYSTEM_RAM;
1049 case E820_TYPE_ACPI: /* Fall-through: */
1050 case E820_TYPE_NVS: /* Fall-through: */
1051 case E820_TYPE_UNUSABLE: /* Fall-through: */
1052 case E820_TYPE_PRAM: /* Fall-through: */
1053 case E820_TYPE_PMEM: /* Fall-through: */
1054 case E820_TYPE_RESERVED: /* Fall-through: */
1055 default: return IORESOURCE_MEM;
1056 }
1057}
1058
1059static unsigned long __init e820_type_to_iores_desc(struct e820_entry *entry)
1060{
1061 switch (entry->type) {
1062 case E820_TYPE_ACPI: return IORES_DESC_ACPI_TABLES;
1063 case E820_TYPE_NVS: return IORES_DESC_ACPI_NV_STORAGE;
1064 case E820_TYPE_PMEM: return IORES_DESC_PERSISTENT_MEMORY;
1065 case E820_TYPE_PRAM: return IORES_DESC_PERSISTENT_MEMORY_LEGACY;
1066 case E820_TYPE_RESERVED: return IORES_DESC_RESERVED;
1067 case E820_TYPE_RESERVED_KERN: /* Fall-through: */
1068 case E820_TYPE_RAM: /* Fall-through: */
1069 case E820_TYPE_UNUSABLE: /* Fall-through: */
1070 default: return IORES_DESC_NONE;
1071 }
1072}
1073
1074static bool __init do_mark_busy(enum e820_type type, struct resource *res)
1075{
1076 /* this is the legacy bios/dos rom-shadow + mmio region */
1077 if (res->start < (1ULL<<20))
1078 return true;
1079
1080 /*
1081 * Treat persistent memory like device memory, i.e. reserve it
1082 * for exclusive use of a driver
1083 */
1084 switch (type) {
1085 case E820_TYPE_RESERVED:
1086 case E820_TYPE_PRAM:
1087 case E820_TYPE_PMEM:
1088 return false;
1089 case E820_TYPE_RESERVED_KERN:
1090 case E820_TYPE_RAM:
1091 case E820_TYPE_ACPI:
1092 case E820_TYPE_NVS:
1093 case E820_TYPE_UNUSABLE:
1094 default:
1095 return true;
1096 }
1097}
1098
1099/*
1100 * Mark E820 reserved areas as busy for the resource manager:
1101 */
1102
1103static struct resource __initdata *e820_res;
1104
1105void __init e820__reserve_resources(void)
1106{
1107 int i;
1108 struct resource *res;
1109 u64 end;
1110
1111 res = memblock_alloc(sizeof(*res) * e820_table->nr_entries,
1112 SMP_CACHE_BYTES);
1113 if (!res)
1114 panic("%s: Failed to allocate %zu bytes\n", __func__,
1115 sizeof(*res) * e820_table->nr_entries);
1116 e820_res = res;
1117
1118 for (i = 0; i < e820_table->nr_entries; i++) {
1119 struct e820_entry *entry = e820_table->entries + i;
1120
1121 end = entry->addr + entry->size - 1;
1122 if (end != (resource_size_t)end) {
1123 res++;
1124 continue;
1125 }
1126 res->start = entry->addr;
1127 res->end = end;
1128 res->name = e820_type_to_string(entry);
1129 res->flags = e820_type_to_iomem_type(entry);
1130 res->desc = e820_type_to_iores_desc(entry);
1131
1132 /*
1133 * Don't register the region that could be conflicted with
1134 * PCI device BAR resources and insert them later in
1135 * pcibios_resource_survey():
1136 */
1137 if (do_mark_busy(entry->type, res)) {
1138 res->flags |= IORESOURCE_BUSY;
1139 insert_resource(&iomem_resource, res);
1140 }
1141 res++;
1142 }
1143
1144 /* Expose the bootloader-provided memory layout to the sysfs. */
1145 for (i = 0; i < e820_table_firmware->nr_entries; i++) {
1146 struct e820_entry *entry = e820_table_firmware->entries + i;
1147
1148 firmware_map_add_early(entry->addr, entry->addr + entry->size, e820_type_to_string(entry));
1149 }
1150}
1151
1152/*
1153 * How much should we pad the end of RAM, depending on where it is?
1154 */
1155static unsigned long __init ram_alignment(resource_size_t pos)
1156{
1157 unsigned long mb = pos >> 20;
1158
1159 /* To 64kB in the first megabyte */
1160 if (!mb)
1161 return 64*1024;
1162
1163 /* To 1MB in the first 16MB */
1164 if (mb < 16)
1165 return 1024*1024;
1166
1167 /* To 64MB for anything above that */
1168 return 64*1024*1024;
1169}
1170
1171#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
1172
1173void __init e820__reserve_resources_late(void)
1174{
1175 int i;
1176 struct resource *res;
1177
1178 res = e820_res;
1179 for (i = 0; i < e820_table->nr_entries; i++) {
1180 if (!res->parent && res->end)
1181 insert_resource_expand_to_fit(&iomem_resource, res);
1182 res++;
1183 }
1184
1185 /*
1186 * Try to bump up RAM regions to reasonable boundaries, to
1187 * avoid stolen RAM:
1188 */
1189 for (i = 0; i < e820_table->nr_entries; i++) {
1190 struct e820_entry *entry = &e820_table->entries[i];
1191 u64 start, end;
1192
1193 if (entry->type != E820_TYPE_RAM)
1194 continue;
1195
1196 start = entry->addr + entry->size;
1197 end = round_up(start, ram_alignment(start)) - 1;
1198 if (end > MAX_RESOURCE_SIZE)
1199 end = MAX_RESOURCE_SIZE;
1200 if (start >= end)
1201 continue;
1202
1203 printk(KERN_DEBUG "e820: reserve RAM buffer [mem %#010llx-%#010llx]\n", start, end);
1204 reserve_region_with_split(&iomem_resource, start, end, "RAM buffer");
1205 }
1206}
1207
1208/*
1209 * Pass the firmware (bootloader) E820 map to the kernel and process it:
1210 */
1211char *__init e820__memory_setup_default(void)
1212{
1213 char *who = "BIOS-e820";
1214
1215 /*
1216 * Try to copy the BIOS-supplied E820-map.
1217 *
1218 * Otherwise fake a memory map; one section from 0k->640k,
1219 * the next section from 1mb->appropriate_mem_k
1220 */
1221 if (append_e820_table(boot_params.e820_table, boot_params.e820_entries) < 0) {
1222 u64 mem_size;
1223
1224 /* Compare results from other methods and take the one that gives more RAM: */
1225 if (boot_params.alt_mem_k < boot_params.screen_info.ext_mem_k) {
1226 mem_size = boot_params.screen_info.ext_mem_k;
1227 who = "BIOS-88";
1228 } else {
1229 mem_size = boot_params.alt_mem_k;
1230 who = "BIOS-e801";
1231 }
1232
1233 e820_table->nr_entries = 0;
1234 e820__range_add(0, LOWMEMSIZE(), E820_TYPE_RAM);
1235 e820__range_add(HIGH_MEMORY, mem_size << 10, E820_TYPE_RAM);
1236 }
1237
1238 /* We just appended a lot of ranges, sanitize the table: */
1239 e820__update_table(e820_table);
1240
1241 return who;
1242}
1243
1244/*
1245 * Calls e820__memory_setup_default() in essence to pick up the firmware/bootloader
1246 * E820 map - with an optional platform quirk available for virtual platforms
1247 * to override this method of boot environment processing:
1248 */
1249void __init e820__memory_setup(void)
1250{
1251 char *who;
1252
1253 /* This is a firmware interface ABI - make sure we don't break it: */
1254 BUILD_BUG_ON(sizeof(struct boot_e820_entry) != 20);
1255
1256 who = x86_init.resources.memory_setup();
1257
1258 memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec));
1259 memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
1260
1261 pr_info("BIOS-provided physical RAM map:\n");
1262 e820__print_table(who);
1263}
1264
1265void __init e820__memblock_setup(void)
1266{
1267 int i;
1268 u64 end;
1269
1270 /*
1271 * The bootstrap memblock region count maximum is 128 entries
1272 * (INIT_MEMBLOCK_REGIONS), but EFI might pass us more E820 entries
1273 * than that - so allow memblock resizing.
1274 *
1275 * This is safe, because this call happens pretty late during x86 setup,
1276 * so we know about reserved memory regions already. (This is important
1277 * so that memblock resizing does no stomp over reserved areas.)
1278 */
1279 memblock_allow_resize();
1280
1281 for (i = 0; i < e820_table->nr_entries; i++) {
1282 struct e820_entry *entry = &e820_table->entries[i];
1283
1284 end = entry->addr + entry->size;
1285 if (end != (resource_size_t)end)
1286 continue;
1287
1288 if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
1289 continue;
1290
1291 memblock_add(entry->addr, entry->size);
1292 }
1293
1294 /* Throw away partial pages: */
1295 memblock_trim_memory(PAGE_SIZE);
1296
1297 memblock_dump_all();
1298}
1/*
2 * Handle the memory map.
3 * The functions here do the job until bootmem takes over.
4 *
5 * Getting sanitize_e820_map() in sync with i386 version by applying change:
6 * - Provisions for empty E820 memory regions (reported by certain BIOSes).
7 * Alex Achenbach <xela@slit.de>, December 2002.
8 * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
9 *
10 */
11#include <linux/kernel.h>
12#include <linux/types.h>
13#include <linux/init.h>
14#include <linux/crash_dump.h>
15#include <linux/export.h>
16#include <linux/bootmem.h>
17#include <linux/pfn.h>
18#include <linux/suspend.h>
19#include <linux/acpi.h>
20#include <linux/firmware-map.h>
21#include <linux/memblock.h>
22#include <linux/sort.h>
23
24#include <asm/e820.h>
25#include <asm/proto.h>
26#include <asm/setup.h>
27#include <asm/cpufeature.h>
28
29/*
30 * The e820 map is the map that gets modified e.g. with command line parameters
31 * and that is also registered with modifications in the kernel resource tree
32 * with the iomem_resource as parent.
33 *
34 * The e820_saved is directly saved after the BIOS-provided memory map is
35 * copied. It doesn't get modified afterwards. It's registered for the
36 * /sys/firmware/memmap interface.
37 *
38 * That memory map is not modified and is used as base for kexec. The kexec'd
39 * kernel should get the same memory map as the firmware provides. Then the
40 * user can e.g. boot the original kernel with mem=1G while still booting the
41 * next kernel with full memory.
42 */
43struct e820map e820;
44struct e820map e820_saved;
45
46/* For PCI or other memory-mapped resources */
47unsigned long pci_mem_start = 0xaeedbabe;
48#ifdef CONFIG_PCI
49EXPORT_SYMBOL(pci_mem_start);
50#endif
51
52/*
53 * This function checks if any part of the range <start,end> is mapped
54 * with type.
55 */
56int
57e820_any_mapped(u64 start, u64 end, unsigned type)
58{
59 int i;
60
61 for (i = 0; i < e820.nr_map; i++) {
62 struct e820entry *ei = &e820.map[i];
63
64 if (type && ei->type != type)
65 continue;
66 if (ei->addr >= end || ei->addr + ei->size <= start)
67 continue;
68 return 1;
69 }
70 return 0;
71}
72EXPORT_SYMBOL_GPL(e820_any_mapped);
73
74/*
75 * This function checks if the entire range <start,end> is mapped with type.
76 *
77 * Note: this function only works correct if the e820 table is sorted and
78 * not-overlapping, which is the case
79 */
80int __init e820_all_mapped(u64 start, u64 end, unsigned type)
81{
82 int i;
83
84 for (i = 0; i < e820.nr_map; i++) {
85 struct e820entry *ei = &e820.map[i];
86
87 if (type && ei->type != type)
88 continue;
89 /* is the region (part) in overlap with the current region ?*/
90 if (ei->addr >= end || ei->addr + ei->size <= start)
91 continue;
92
93 /* if the region is at the beginning of <start,end> we move
94 * start to the end of the region since it's ok until there
95 */
96 if (ei->addr <= start)
97 start = ei->addr + ei->size;
98 /*
99 * if start is now at or beyond end, we're done, full
100 * coverage
101 */
102 if (start >= end)
103 return 1;
104 }
105 return 0;
106}
107
108/*
109 * Add a memory region to the kernel e820 map.
110 */
111static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
112 int type)
113{
114 int x = e820x->nr_map;
115
116 if (x >= ARRAY_SIZE(e820x->map)) {
117 printk(KERN_ERR "e820: too many entries; ignoring [mem %#010llx-%#010llx]\n",
118 (unsigned long long) start,
119 (unsigned long long) (start + size - 1));
120 return;
121 }
122
123 e820x->map[x].addr = start;
124 e820x->map[x].size = size;
125 e820x->map[x].type = type;
126 e820x->nr_map++;
127}
128
129void __init e820_add_region(u64 start, u64 size, int type)
130{
131 __e820_add_region(&e820, start, size, type);
132}
133
134static void __init e820_print_type(u32 type)
135{
136 switch (type) {
137 case E820_RAM:
138 case E820_RESERVED_KERN:
139 printk(KERN_CONT "usable");
140 break;
141 case E820_RESERVED:
142 printk(KERN_CONT "reserved");
143 break;
144 case E820_ACPI:
145 printk(KERN_CONT "ACPI data");
146 break;
147 case E820_NVS:
148 printk(KERN_CONT "ACPI NVS");
149 break;
150 case E820_UNUSABLE:
151 printk(KERN_CONT "unusable");
152 break;
153 case E820_PMEM:
154 case E820_PRAM:
155 printk(KERN_CONT "persistent (type %u)", type);
156 break;
157 default:
158 printk(KERN_CONT "type %u", type);
159 break;
160 }
161}
162
163void __init e820_print_map(char *who)
164{
165 int i;
166
167 for (i = 0; i < e820.nr_map; i++) {
168 printk(KERN_INFO "%s: [mem %#018Lx-%#018Lx] ", who,
169 (unsigned long long) e820.map[i].addr,
170 (unsigned long long)
171 (e820.map[i].addr + e820.map[i].size - 1));
172 e820_print_type(e820.map[i].type);
173 printk(KERN_CONT "\n");
174 }
175}
176
177/*
178 * Sanitize the BIOS e820 map.
179 *
180 * Some e820 responses include overlapping entries. The following
181 * replaces the original e820 map with a new one, removing overlaps,
182 * and resolving conflicting memory types in favor of highest
183 * numbered type.
184 *
185 * The input parameter biosmap points to an array of 'struct
186 * e820entry' which on entry has elements in the range [0, *pnr_map)
187 * valid, and which has space for up to max_nr_map entries.
188 * On return, the resulting sanitized e820 map entries will be in
189 * overwritten in the same location, starting at biosmap.
190 *
191 * The integer pointed to by pnr_map must be valid on entry (the
192 * current number of valid entries located at biosmap). If the
193 * sanitizing succeeds the *pnr_map will be updated with the new
194 * number of valid entries (something no more than max_nr_map).
195 *
196 * The return value from sanitize_e820_map() is zero if it
197 * successfully 'sanitized' the map entries passed in, and is -1
198 * if it did nothing, which can happen if either of (1) it was
199 * only passed one map entry, or (2) any of the input map entries
200 * were invalid (start + size < start, meaning that the size was
201 * so big the described memory range wrapped around through zero.)
202 *
203 * Visually we're performing the following
204 * (1,2,3,4 = memory types)...
205 *
206 * Sample memory map (w/overlaps):
207 * ____22__________________
208 * ______________________4_
209 * ____1111________________
210 * _44_____________________
211 * 11111111________________
212 * ____________________33__
213 * ___________44___________
214 * __________33333_________
215 * ______________22________
216 * ___________________2222_
217 * _________111111111______
218 * _____________________11_
219 * _________________4______
220 *
221 * Sanitized equivalent (no overlap):
222 * 1_______________________
223 * _44_____________________
224 * ___1____________________
225 * ____22__________________
226 * ______11________________
227 * _________1______________
228 * __________3_____________
229 * ___________44___________
230 * _____________33_________
231 * _______________2________
232 * ________________1_______
233 * _________________4______
234 * ___________________2____
235 * ____________________33__
236 * ______________________4_
237 */
238struct change_member {
239 struct e820entry *pbios; /* pointer to original bios entry */
240 unsigned long long addr; /* address for this change point */
241};
242
243static int __init cpcompare(const void *a, const void *b)
244{
245 struct change_member * const *app = a, * const *bpp = b;
246 const struct change_member *ap = *app, *bp = *bpp;
247
248 /*
249 * Inputs are pointers to two elements of change_point[]. If their
250 * addresses are unequal, their difference dominates. If the addresses
251 * are equal, then consider one that represents the end of its region
252 * to be greater than one that does not.
253 */
254 if (ap->addr != bp->addr)
255 return ap->addr > bp->addr ? 1 : -1;
256
257 return (ap->addr != ap->pbios->addr) - (bp->addr != bp->pbios->addr);
258}
259
260int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
261 u32 *pnr_map)
262{
263 static struct change_member change_point_list[2*E820_X_MAX] __initdata;
264 static struct change_member *change_point[2*E820_X_MAX] __initdata;
265 static struct e820entry *overlap_list[E820_X_MAX] __initdata;
266 static struct e820entry new_bios[E820_X_MAX] __initdata;
267 unsigned long current_type, last_type;
268 unsigned long long last_addr;
269 int chgidx;
270 int overlap_entries;
271 int new_bios_entry;
272 int old_nr, new_nr, chg_nr;
273 int i;
274
275 /* if there's only one memory region, don't bother */
276 if (*pnr_map < 2)
277 return -1;
278
279 old_nr = *pnr_map;
280 BUG_ON(old_nr > max_nr_map);
281
282 /* bail out if we find any unreasonable addresses in bios map */
283 for (i = 0; i < old_nr; i++)
284 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
285 return -1;
286
287 /* create pointers for initial change-point information (for sorting) */
288 for (i = 0; i < 2 * old_nr; i++)
289 change_point[i] = &change_point_list[i];
290
291 /* record all known change-points (starting and ending addresses),
292 omitting those that are for empty memory regions */
293 chgidx = 0;
294 for (i = 0; i < old_nr; i++) {
295 if (biosmap[i].size != 0) {
296 change_point[chgidx]->addr = biosmap[i].addr;
297 change_point[chgidx++]->pbios = &biosmap[i];
298 change_point[chgidx]->addr = biosmap[i].addr +
299 biosmap[i].size;
300 change_point[chgidx++]->pbios = &biosmap[i];
301 }
302 }
303 chg_nr = chgidx;
304
305 /* sort change-point list by memory addresses (low -> high) */
306 sort(change_point, chg_nr, sizeof *change_point, cpcompare, NULL);
307
308 /* create a new bios memory map, removing overlaps */
309 overlap_entries = 0; /* number of entries in the overlap table */
310 new_bios_entry = 0; /* index for creating new bios map entries */
311 last_type = 0; /* start with undefined memory type */
312 last_addr = 0; /* start with 0 as last starting address */
313
314 /* loop through change-points, determining affect on the new bios map */
315 for (chgidx = 0; chgidx < chg_nr; chgidx++) {
316 /* keep track of all overlapping bios entries */
317 if (change_point[chgidx]->addr ==
318 change_point[chgidx]->pbios->addr) {
319 /*
320 * add map entry to overlap list (> 1 entry
321 * implies an overlap)
322 */
323 overlap_list[overlap_entries++] =
324 change_point[chgidx]->pbios;
325 } else {
326 /*
327 * remove entry from list (order independent,
328 * so swap with last)
329 */
330 for (i = 0; i < overlap_entries; i++) {
331 if (overlap_list[i] ==
332 change_point[chgidx]->pbios)
333 overlap_list[i] =
334 overlap_list[overlap_entries-1];
335 }
336 overlap_entries--;
337 }
338 /*
339 * if there are overlapping entries, decide which
340 * "type" to use (larger value takes precedence --
341 * 1=usable, 2,3,4,4+=unusable)
342 */
343 current_type = 0;
344 for (i = 0; i < overlap_entries; i++)
345 if (overlap_list[i]->type > current_type)
346 current_type = overlap_list[i]->type;
347 /*
348 * continue building up new bios map based on this
349 * information
350 */
351 if (current_type != last_type || current_type == E820_PRAM) {
352 if (last_type != 0) {
353 new_bios[new_bios_entry].size =
354 change_point[chgidx]->addr - last_addr;
355 /*
356 * move forward only if the new size
357 * was non-zero
358 */
359 if (new_bios[new_bios_entry].size != 0)
360 /*
361 * no more space left for new
362 * bios entries ?
363 */
364 if (++new_bios_entry >= max_nr_map)
365 break;
366 }
367 if (current_type != 0) {
368 new_bios[new_bios_entry].addr =
369 change_point[chgidx]->addr;
370 new_bios[new_bios_entry].type = current_type;
371 last_addr = change_point[chgidx]->addr;
372 }
373 last_type = current_type;
374 }
375 }
376 /* retain count for new bios entries */
377 new_nr = new_bios_entry;
378
379 /* copy new bios mapping into original location */
380 memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
381 *pnr_map = new_nr;
382
383 return 0;
384}
385
386static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
387{
388 while (nr_map) {
389 u64 start = biosmap->addr;
390 u64 size = biosmap->size;
391 u64 end = start + size;
392 u32 type = biosmap->type;
393
394 /* Overflow in 64 bits? Ignore the memory map. */
395 if (start > end)
396 return -1;
397
398 e820_add_region(start, size, type);
399
400 biosmap++;
401 nr_map--;
402 }
403 return 0;
404}
405
406/*
407 * Copy the BIOS e820 map into a safe place.
408 *
409 * Sanity-check it while we're at it..
410 *
411 * If we're lucky and live on a modern system, the setup code
412 * will have given us a memory map that we can use to properly
413 * set up memory. If we aren't, we'll fake a memory map.
414 */
415static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
416{
417 /* Only one memory region (or negative)? Ignore it */
418 if (nr_map < 2)
419 return -1;
420
421 return __append_e820_map(biosmap, nr_map);
422}
423
424static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
425 u64 size, unsigned old_type,
426 unsigned new_type)
427{
428 u64 end;
429 unsigned int i;
430 u64 real_updated_size = 0;
431
432 BUG_ON(old_type == new_type);
433
434 if (size > (ULLONG_MAX - start))
435 size = ULLONG_MAX - start;
436
437 end = start + size;
438 printk(KERN_DEBUG "e820: update [mem %#010Lx-%#010Lx] ",
439 (unsigned long long) start, (unsigned long long) (end - 1));
440 e820_print_type(old_type);
441 printk(KERN_CONT " ==> ");
442 e820_print_type(new_type);
443 printk(KERN_CONT "\n");
444
445 for (i = 0; i < e820x->nr_map; i++) {
446 struct e820entry *ei = &e820x->map[i];
447 u64 final_start, final_end;
448 u64 ei_end;
449
450 if (ei->type != old_type)
451 continue;
452
453 ei_end = ei->addr + ei->size;
454 /* totally covered by new range? */
455 if (ei->addr >= start && ei_end <= end) {
456 ei->type = new_type;
457 real_updated_size += ei->size;
458 continue;
459 }
460
461 /* new range is totally covered? */
462 if (ei->addr < start && ei_end > end) {
463 __e820_add_region(e820x, start, size, new_type);
464 __e820_add_region(e820x, end, ei_end - end, ei->type);
465 ei->size = start - ei->addr;
466 real_updated_size += size;
467 continue;
468 }
469
470 /* partially covered */
471 final_start = max(start, ei->addr);
472 final_end = min(end, ei_end);
473 if (final_start >= final_end)
474 continue;
475
476 __e820_add_region(e820x, final_start, final_end - final_start,
477 new_type);
478
479 real_updated_size += final_end - final_start;
480
481 /*
482 * left range could be head or tail, so need to update
483 * size at first.
484 */
485 ei->size -= final_end - final_start;
486 if (ei->addr < final_start)
487 continue;
488 ei->addr = final_end;
489 }
490 return real_updated_size;
491}
492
493u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
494 unsigned new_type)
495{
496 return __e820_update_range(&e820, start, size, old_type, new_type);
497}
498
499static u64 __init e820_update_range_saved(u64 start, u64 size,
500 unsigned old_type, unsigned new_type)
501{
502 return __e820_update_range(&e820_saved, start, size, old_type,
503 new_type);
504}
505
506/* make e820 not cover the range */
507u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
508 int checktype)
509{
510 int i;
511 u64 end;
512 u64 real_removed_size = 0;
513
514 if (size > (ULLONG_MAX - start))
515 size = ULLONG_MAX - start;
516
517 end = start + size;
518 printk(KERN_DEBUG "e820: remove [mem %#010Lx-%#010Lx] ",
519 (unsigned long long) start, (unsigned long long) (end - 1));
520 if (checktype)
521 e820_print_type(old_type);
522 printk(KERN_CONT "\n");
523
524 for (i = 0; i < e820.nr_map; i++) {
525 struct e820entry *ei = &e820.map[i];
526 u64 final_start, final_end;
527 u64 ei_end;
528
529 if (checktype && ei->type != old_type)
530 continue;
531
532 ei_end = ei->addr + ei->size;
533 /* totally covered? */
534 if (ei->addr >= start && ei_end <= end) {
535 real_removed_size += ei->size;
536 memset(ei, 0, sizeof(struct e820entry));
537 continue;
538 }
539
540 /* new range is totally covered? */
541 if (ei->addr < start && ei_end > end) {
542 e820_add_region(end, ei_end - end, ei->type);
543 ei->size = start - ei->addr;
544 real_removed_size += size;
545 continue;
546 }
547
548 /* partially covered */
549 final_start = max(start, ei->addr);
550 final_end = min(end, ei_end);
551 if (final_start >= final_end)
552 continue;
553 real_removed_size += final_end - final_start;
554
555 /*
556 * left range could be head or tail, so need to update
557 * size at first.
558 */
559 ei->size -= final_end - final_start;
560 if (ei->addr < final_start)
561 continue;
562 ei->addr = final_end;
563 }
564 return real_removed_size;
565}
566
567void __init update_e820(void)
568{
569 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map))
570 return;
571 printk(KERN_INFO "e820: modified physical RAM map:\n");
572 e820_print_map("modified");
573}
574static void __init update_e820_saved(void)
575{
576 sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map),
577 &e820_saved.nr_map);
578}
579#define MAX_GAP_END 0x100000000ull
580/*
581 * Search for a gap in the e820 memory space from start_addr to end_addr.
582 */
583__init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
584 unsigned long start_addr, unsigned long long end_addr)
585{
586 unsigned long long last;
587 int i = e820.nr_map;
588 int found = 0;
589
590 last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
591
592 while (--i >= 0) {
593 unsigned long long start = e820.map[i].addr;
594 unsigned long long end = start + e820.map[i].size;
595
596 if (end < start_addr)
597 continue;
598
599 /*
600 * Since "last" is at most 4GB, we know we'll
601 * fit in 32 bits if this condition is true
602 */
603 if (last > end) {
604 unsigned long gap = last - end;
605
606 if (gap >= *gapsize) {
607 *gapsize = gap;
608 *gapstart = end;
609 found = 1;
610 }
611 }
612 if (start < last)
613 last = start;
614 }
615 return found;
616}
617
618/*
619 * Search for the biggest gap in the low 32 bits of the e820
620 * memory space. We pass this space to PCI to assign MMIO resources
621 * for hotplug or unconfigured devices in.
622 * Hopefully the BIOS let enough space left.
623 */
624__init void e820_setup_gap(void)
625{
626 unsigned long gapstart, gapsize;
627 int found;
628
629 gapstart = 0x10000000;
630 gapsize = 0x400000;
631 found = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
632
633#ifdef CONFIG_X86_64
634 if (!found) {
635 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
636 printk(KERN_ERR
637 "e820: cannot find a gap in the 32bit address range\n"
638 "e820: PCI devices with unassigned 32bit BARs may break!\n");
639 }
640#endif
641
642 /*
643 * e820_reserve_resources_late protect stolen RAM already
644 */
645 pci_mem_start = gapstart;
646
647 printk(KERN_INFO
648 "e820: [mem %#010lx-%#010lx] available for PCI devices\n",
649 gapstart, gapstart + gapsize - 1);
650}
651
652/**
653 * Because of the size limitation of struct boot_params, only first
654 * 128 E820 memory entries are passed to kernel via
655 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
656 * linked list of struct setup_data, which is parsed here.
657 */
658void __init parse_e820_ext(u64 phys_addr, u32 data_len)
659{
660 int entries;
661 struct e820entry *extmap;
662 struct setup_data *sdata;
663
664 sdata = early_memremap(phys_addr, data_len);
665 entries = sdata->len / sizeof(struct e820entry);
666 extmap = (struct e820entry *)(sdata->data);
667 __append_e820_map(extmap, entries);
668 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
669 early_memunmap(sdata, data_len);
670 printk(KERN_INFO "e820: extended physical RAM map:\n");
671 e820_print_map("extended");
672}
673
674#if defined(CONFIG_X86_64) || \
675 (defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
676/**
677 * Find the ranges of physical addresses that do not correspond to
678 * e820 RAM areas and mark the corresponding pages as nosave for
679 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
680 *
681 * This function requires the e820 map to be sorted and without any
682 * overlapping entries.
683 */
684void __init e820_mark_nosave_regions(unsigned long limit_pfn)
685{
686 int i;
687 unsigned long pfn = 0;
688
689 for (i = 0; i < e820.nr_map; i++) {
690 struct e820entry *ei = &e820.map[i];
691
692 if (pfn < PFN_UP(ei->addr))
693 register_nosave_region(pfn, PFN_UP(ei->addr));
694
695 pfn = PFN_DOWN(ei->addr + ei->size);
696
697 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
698 register_nosave_region(PFN_UP(ei->addr), pfn);
699
700 if (pfn >= limit_pfn)
701 break;
702 }
703}
704#endif
705
706#ifdef CONFIG_ACPI
707/**
708 * Mark ACPI NVS memory region, so that we can save/restore it during
709 * hibernation and the subsequent resume.
710 */
711static int __init e820_mark_nvs_memory(void)
712{
713 int i;
714
715 for (i = 0; i < e820.nr_map; i++) {
716 struct e820entry *ei = &e820.map[i];
717
718 if (ei->type == E820_NVS)
719 acpi_nvs_register(ei->addr, ei->size);
720 }
721
722 return 0;
723}
724core_initcall(e820_mark_nvs_memory);
725#endif
726
727/*
728 * pre allocated 4k and reserved it in memblock and e820_saved
729 */
730u64 __init early_reserve_e820(u64 size, u64 align)
731{
732 u64 addr;
733
734 addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
735 if (addr) {
736 e820_update_range_saved(addr, size, E820_RAM, E820_RESERVED);
737 printk(KERN_INFO "e820: update e820_saved for early_reserve_e820\n");
738 update_e820_saved();
739 }
740
741 return addr;
742}
743
744#ifdef CONFIG_X86_32
745# ifdef CONFIG_X86_PAE
746# define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
747# else
748# define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
749# endif
750#else /* CONFIG_X86_32 */
751# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
752#endif
753
754/*
755 * Find the highest page frame number we have available
756 */
757static unsigned long __init e820_end_pfn(unsigned long limit_pfn)
758{
759 int i;
760 unsigned long last_pfn = 0;
761 unsigned long max_arch_pfn = MAX_ARCH_PFN;
762
763 for (i = 0; i < e820.nr_map; i++) {
764 struct e820entry *ei = &e820.map[i];
765 unsigned long start_pfn;
766 unsigned long end_pfn;
767
768 /*
769 * Persistent memory is accounted as ram for purposes of
770 * establishing max_pfn and mem_map.
771 */
772 if (ei->type != E820_RAM && ei->type != E820_PRAM)
773 continue;
774
775 start_pfn = ei->addr >> PAGE_SHIFT;
776 end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
777
778 if (start_pfn >= limit_pfn)
779 continue;
780 if (end_pfn > limit_pfn) {
781 last_pfn = limit_pfn;
782 break;
783 }
784 if (end_pfn > last_pfn)
785 last_pfn = end_pfn;
786 }
787
788 if (last_pfn > max_arch_pfn)
789 last_pfn = max_arch_pfn;
790
791 printk(KERN_INFO "e820: last_pfn = %#lx max_arch_pfn = %#lx\n",
792 last_pfn, max_arch_pfn);
793 return last_pfn;
794}
795unsigned long __init e820_end_of_ram_pfn(void)
796{
797 return e820_end_pfn(MAX_ARCH_PFN);
798}
799
800unsigned long __init e820_end_of_low_ram_pfn(void)
801{
802 return e820_end_pfn(1UL << (32-PAGE_SHIFT));
803}
804
805static void early_panic(char *msg)
806{
807 early_printk(msg);
808 panic(msg);
809}
810
811static int userdef __initdata;
812
813/* "mem=nopentium" disables the 4MB page tables. */
814static int __init parse_memopt(char *p)
815{
816 u64 mem_size;
817
818 if (!p)
819 return -EINVAL;
820
821 if (!strcmp(p, "nopentium")) {
822#ifdef CONFIG_X86_32
823 setup_clear_cpu_cap(X86_FEATURE_PSE);
824 return 0;
825#else
826 printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
827 return -EINVAL;
828#endif
829 }
830
831 userdef = 1;
832 mem_size = memparse(p, &p);
833 /* don't remove all of memory when handling "mem={invalid}" param */
834 if (mem_size == 0)
835 return -EINVAL;
836 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
837
838 return 0;
839}
840early_param("mem", parse_memopt);
841
842static int __init parse_memmap_one(char *p)
843{
844 char *oldp;
845 u64 start_at, mem_size;
846
847 if (!p)
848 return -EINVAL;
849
850 if (!strncmp(p, "exactmap", 8)) {
851#ifdef CONFIG_CRASH_DUMP
852 /*
853 * If we are doing a crash dump, we still need to know
854 * the real mem size before original memory map is
855 * reset.
856 */
857 saved_max_pfn = e820_end_of_ram_pfn();
858#endif
859 e820.nr_map = 0;
860 userdef = 1;
861 return 0;
862 }
863
864 oldp = p;
865 mem_size = memparse(p, &p);
866 if (p == oldp)
867 return -EINVAL;
868
869 userdef = 1;
870 if (*p == '@') {
871 start_at = memparse(p+1, &p);
872 e820_add_region(start_at, mem_size, E820_RAM);
873 } else if (*p == '#') {
874 start_at = memparse(p+1, &p);
875 e820_add_region(start_at, mem_size, E820_ACPI);
876 } else if (*p == '$') {
877 start_at = memparse(p+1, &p);
878 e820_add_region(start_at, mem_size, E820_RESERVED);
879 } else if (*p == '!') {
880 start_at = memparse(p+1, &p);
881 e820_add_region(start_at, mem_size, E820_PRAM);
882 } else
883 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
884
885 return *p == '\0' ? 0 : -EINVAL;
886}
887static int __init parse_memmap_opt(char *str)
888{
889 while (str) {
890 char *k = strchr(str, ',');
891
892 if (k)
893 *k++ = 0;
894
895 parse_memmap_one(str);
896 str = k;
897 }
898
899 return 0;
900}
901early_param("memmap", parse_memmap_opt);
902
903void __init finish_e820_parsing(void)
904{
905 if (userdef) {
906 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map),
907 &e820.nr_map) < 0)
908 early_panic("Invalid user supplied memory map");
909
910 printk(KERN_INFO "e820: user-defined physical RAM map:\n");
911 e820_print_map("user");
912 }
913}
914
915static const char *e820_type_to_string(int e820_type)
916{
917 switch (e820_type) {
918 case E820_RESERVED_KERN:
919 case E820_RAM: return "System RAM";
920 case E820_ACPI: return "ACPI Tables";
921 case E820_NVS: return "ACPI Non-volatile Storage";
922 case E820_UNUSABLE: return "Unusable memory";
923 case E820_PRAM: return "Persistent Memory (legacy)";
924 case E820_PMEM: return "Persistent Memory";
925 default: return "reserved";
926 }
927}
928
929static unsigned long e820_type_to_iomem_type(int e820_type)
930{
931 switch (e820_type) {
932 case E820_RESERVED_KERN:
933 case E820_RAM:
934 return IORESOURCE_SYSTEM_RAM;
935 case E820_ACPI:
936 case E820_NVS:
937 case E820_UNUSABLE:
938 case E820_PRAM:
939 case E820_PMEM:
940 default:
941 return IORESOURCE_MEM;
942 }
943}
944
945static unsigned long e820_type_to_iores_desc(int e820_type)
946{
947 switch (e820_type) {
948 case E820_ACPI:
949 return IORES_DESC_ACPI_TABLES;
950 case E820_NVS:
951 return IORES_DESC_ACPI_NV_STORAGE;
952 case E820_PMEM:
953 return IORES_DESC_PERSISTENT_MEMORY;
954 case E820_PRAM:
955 return IORES_DESC_PERSISTENT_MEMORY_LEGACY;
956 case E820_RESERVED_KERN:
957 case E820_RAM:
958 case E820_UNUSABLE:
959 default:
960 return IORES_DESC_NONE;
961 }
962}
963
964static bool do_mark_busy(u32 type, struct resource *res)
965{
966 /* this is the legacy bios/dos rom-shadow + mmio region */
967 if (res->start < (1ULL<<20))
968 return true;
969
970 /*
971 * Treat persistent memory like device memory, i.e. reserve it
972 * for exclusive use of a driver
973 */
974 switch (type) {
975 case E820_RESERVED:
976 case E820_PRAM:
977 case E820_PMEM:
978 return false;
979 default:
980 return true;
981 }
982}
983
984/*
985 * Mark e820 reserved areas as busy for the resource manager.
986 */
987static struct resource __initdata *e820_res;
988void __init e820_reserve_resources(void)
989{
990 int i;
991 struct resource *res;
992 u64 end;
993
994 res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
995 e820_res = res;
996 for (i = 0; i < e820.nr_map; i++) {
997 end = e820.map[i].addr + e820.map[i].size - 1;
998 if (end != (resource_size_t)end) {
999 res++;
1000 continue;
1001 }
1002 res->name = e820_type_to_string(e820.map[i].type);
1003 res->start = e820.map[i].addr;
1004 res->end = end;
1005
1006 res->flags = e820_type_to_iomem_type(e820.map[i].type);
1007 res->desc = e820_type_to_iores_desc(e820.map[i].type);
1008
1009 /*
1010 * don't register the region that could be conflicted with
1011 * pci device BAR resource and insert them later in
1012 * pcibios_resource_survey()
1013 */
1014 if (do_mark_busy(e820.map[i].type, res)) {
1015 res->flags |= IORESOURCE_BUSY;
1016 insert_resource(&iomem_resource, res);
1017 }
1018 res++;
1019 }
1020
1021 for (i = 0; i < e820_saved.nr_map; i++) {
1022 struct e820entry *entry = &e820_saved.map[i];
1023 firmware_map_add_early(entry->addr,
1024 entry->addr + entry->size,
1025 e820_type_to_string(entry->type));
1026 }
1027}
1028
1029/* How much should we pad RAM ending depending on where it is? */
1030static unsigned long ram_alignment(resource_size_t pos)
1031{
1032 unsigned long mb = pos >> 20;
1033
1034 /* To 64kB in the first megabyte */
1035 if (!mb)
1036 return 64*1024;
1037
1038 /* To 1MB in the first 16MB */
1039 if (mb < 16)
1040 return 1024*1024;
1041
1042 /* To 64MB for anything above that */
1043 return 64*1024*1024;
1044}
1045
1046#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
1047
1048void __init e820_reserve_resources_late(void)
1049{
1050 int i;
1051 struct resource *res;
1052
1053 res = e820_res;
1054 for (i = 0; i < e820.nr_map; i++) {
1055 if (!res->parent && res->end)
1056 insert_resource_expand_to_fit(&iomem_resource, res);
1057 res++;
1058 }
1059
1060 /*
1061 * Try to bump up RAM regions to reasonable boundaries to
1062 * avoid stolen RAM:
1063 */
1064 for (i = 0; i < e820.nr_map; i++) {
1065 struct e820entry *entry = &e820.map[i];
1066 u64 start, end;
1067
1068 if (entry->type != E820_RAM)
1069 continue;
1070 start = entry->addr + entry->size;
1071 end = round_up(start, ram_alignment(start)) - 1;
1072 if (end > MAX_RESOURCE_SIZE)
1073 end = MAX_RESOURCE_SIZE;
1074 if (start >= end)
1075 continue;
1076 printk(KERN_DEBUG
1077 "e820: reserve RAM buffer [mem %#010llx-%#010llx]\n",
1078 start, end);
1079 reserve_region_with_split(&iomem_resource, start, end,
1080 "RAM buffer");
1081 }
1082}
1083
1084char *__init default_machine_specific_memory_setup(void)
1085{
1086 char *who = "BIOS-e820";
1087 u32 new_nr;
1088 /*
1089 * Try to copy the BIOS-supplied E820-map.
1090 *
1091 * Otherwise fake a memory map; one section from 0k->640k,
1092 * the next section from 1mb->appropriate_mem_k
1093 */
1094 new_nr = boot_params.e820_entries;
1095 sanitize_e820_map(boot_params.e820_map,
1096 ARRAY_SIZE(boot_params.e820_map),
1097 &new_nr);
1098 boot_params.e820_entries = new_nr;
1099 if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1100 < 0) {
1101 u64 mem_size;
1102
1103 /* compare results from other methods and take the greater */
1104 if (boot_params.alt_mem_k
1105 < boot_params.screen_info.ext_mem_k) {
1106 mem_size = boot_params.screen_info.ext_mem_k;
1107 who = "BIOS-88";
1108 } else {
1109 mem_size = boot_params.alt_mem_k;
1110 who = "BIOS-e801";
1111 }
1112
1113 e820.nr_map = 0;
1114 e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1115 e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1116 }
1117
1118 /* In case someone cares... */
1119 return who;
1120}
1121
1122void __init setup_memory_map(void)
1123{
1124 char *who;
1125
1126 who = x86_init.resources.memory_setup();
1127 memcpy(&e820_saved, &e820, sizeof(struct e820map));
1128 printk(KERN_INFO "e820: BIOS-provided physical RAM map:\n");
1129 e820_print_map(who);
1130}
1131
1132void __init memblock_x86_fill(void)
1133{
1134 int i;
1135 u64 end;
1136
1137 /*
1138 * EFI may have more than 128 entries
1139 * We are safe to enable resizing, beause memblock_x86_fill()
1140 * is rather later for x86
1141 */
1142 memblock_allow_resize();
1143
1144 for (i = 0; i < e820.nr_map; i++) {
1145 struct e820entry *ei = &e820.map[i];
1146
1147 end = ei->addr + ei->size;
1148 if (end != (resource_size_t)end)
1149 continue;
1150
1151 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
1152 continue;
1153
1154 memblock_add(ei->addr, ei->size);
1155 }
1156
1157 /* throw away partial pages */
1158 memblock_trim_memory(PAGE_SIZE);
1159
1160 memblock_dump_all();
1161}
1162
1163void __init memblock_find_dma_reserve(void)
1164{
1165#ifdef CONFIG_X86_64
1166 u64 nr_pages = 0, nr_free_pages = 0;
1167 unsigned long start_pfn, end_pfn;
1168 phys_addr_t start, end;
1169 int i;
1170 u64 u;
1171
1172 /*
1173 * need to find out used area below MAX_DMA_PFN
1174 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1175 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1176 */
1177 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
1178 start_pfn = min(start_pfn, MAX_DMA_PFN);
1179 end_pfn = min(end_pfn, MAX_DMA_PFN);
1180 nr_pages += end_pfn - start_pfn;
1181 }
1182
1183 for_each_free_mem_range(u, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end,
1184 NULL) {
1185 start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN);
1186 end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN);
1187 if (start_pfn < end_pfn)
1188 nr_free_pages += end_pfn - start_pfn;
1189 }
1190
1191 set_dma_reserve(nr_pages - nr_free_pages);
1192#endif
1193}