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1/*
2 * Low level x86 E820 memory map handling functions.
3 *
4 * The firmware and bootloader passes us the "E820 table", which is the primary
5 * physical memory layout description available about x86 systems.
6 *
7 * The kernel takes the E820 memory layout and optionally modifies it with
8 * quirks and other tweaks, and feeds that into the generic Linux memory
9 * allocation code routines via a platform independent interface (memblock, etc.).
10 */
11#include <linux/crash_dump.h>
12#include <linux/bootmem.h>
13#include <linux/suspend.h>
14#include <linux/acpi.h>
15#include <linux/firmware-map.h>
16#include <linux/memblock.h>
17#include <linux/sort.h>
18
19#include <asm/e820/api.h>
20#include <asm/setup.h>
21
22/*
23 * We organize the E820 table into three main data structures:
24 *
25 * - 'e820_table_firmware': the original firmware version passed to us by the
26 * bootloader - not modified by the kernel. It is composed of two parts:
27 * the first 128 E820 memory entries in boot_params.e820_table and the remaining
28 * (if any) entries of the SETUP_E820_EXT nodes. We use this to:
29 *
30 * - inform the user about the firmware's notion of memory layout
31 * via /sys/firmware/memmap
32 *
33 * - the hibernation code uses it to generate a kernel-independent MD5
34 * fingerprint of the physical memory layout of a system.
35 *
36 * - 'e820_table_kexec': a slightly modified (by the kernel) firmware version
37 * passed to us by the bootloader - the major difference between
38 * e820_table_firmware[] and this one is that, the latter marks the setup_data
39 * list created by the EFI boot stub as reserved, so that kexec can reuse the
40 * setup_data information in the second kernel. Besides, e820_table_kexec[]
41 * might also be modified by the kexec itself to fake a mptable.
42 * We use this to:
43 *
44 * - kexec, which is a bootloader in disguise, uses the original E820
45 * layout to pass to the kexec-ed kernel. This way the original kernel
46 * can have a restricted E820 map while the kexec()-ed kexec-kernel
47 * can have access to full memory - etc.
48 *
49 * - 'e820_table': this is the main E820 table that is massaged by the
50 * low level x86 platform code, or modified by boot parameters, before
51 * passed on to higher level MM layers.
52 *
53 * Once the E820 map has been converted to the standard Linux memory layout
54 * information its role stops - modifying it has no effect and does not get
55 * re-propagated. So itsmain role is a temporary bootstrap storage of firmware
56 * specific memory layout data during early bootup.
57 */
58static struct e820_table e820_table_init __initdata;
59static struct e820_table e820_table_kexec_init __initdata;
60static struct e820_table e820_table_firmware_init __initdata;
61
62struct e820_table *e820_table __refdata = &e820_table_init;
63struct e820_table *e820_table_kexec __refdata = &e820_table_kexec_init;
64struct e820_table *e820_table_firmware __refdata = &e820_table_firmware_init;
65
66/* For PCI or other memory-mapped resources */
67unsigned long pci_mem_start = 0xaeedbabe;
68#ifdef CONFIG_PCI
69EXPORT_SYMBOL(pci_mem_start);
70#endif
71
72/*
73 * This function checks if any part of the range <start,end> is mapped
74 * with type.
75 */
76bool e820__mapped_any(u64 start, u64 end, enum e820_type type)
77{
78 int i;
79
80 for (i = 0; i < e820_table->nr_entries; i++) {
81 struct e820_entry *entry = &e820_table->entries[i];
82
83 if (type && entry->type != type)
84 continue;
85 if (entry->addr >= end || entry->addr + entry->size <= start)
86 continue;
87 return 1;
88 }
89 return 0;
90}
91EXPORT_SYMBOL_GPL(e820__mapped_any);
92
93/*
94 * This function checks if the entire <start,end> range is mapped with 'type'.
95 *
96 * Note: this function only works correctly once the E820 table is sorted and
97 * not-overlapping (at least for the range specified), which is the case normally.
98 */
99static struct e820_entry *__e820__mapped_all(u64 start, u64 end,
100 enum e820_type type)
101{
102 int i;
103
104 for (i = 0; i < e820_table->nr_entries; i++) {
105 struct e820_entry *entry = &e820_table->entries[i];
106
107 if (type && entry->type != type)
108 continue;
109
110 /* Is the region (part) in overlap with the current region? */
111 if (entry->addr >= end || entry->addr + entry->size <= start)
112 continue;
113
114 /*
115 * If the region is at the beginning of <start,end> we move
116 * 'start' to the end of the region since it's ok until there
117 */
118 if (entry->addr <= start)
119 start = entry->addr + entry->size;
120
121 /*
122 * If 'start' is now at or beyond 'end', we're done, full
123 * coverage of the desired range exists:
124 */
125 if (start >= end)
126 return entry;
127 }
128
129 return NULL;
130}
131
132/*
133 * This function checks if the entire range <start,end> is mapped with type.
134 */
135bool __init e820__mapped_all(u64 start, u64 end, enum e820_type type)
136{
137 return __e820__mapped_all(start, end, type);
138}
139
140/*
141 * This function returns the type associated with the range <start,end>.
142 */
143int e820__get_entry_type(u64 start, u64 end)
144{
145 struct e820_entry *entry = __e820__mapped_all(start, end, 0);
146
147 return entry ? entry->type : -EINVAL;
148}
149
150/*
151 * Add a memory region to the kernel E820 map.
152 */
153static void __init __e820__range_add(struct e820_table *table, u64 start, u64 size, enum e820_type type)
154{
155 int x = table->nr_entries;
156
157 if (x >= ARRAY_SIZE(table->entries)) {
158 pr_err("e820: too many entries; ignoring [mem %#010llx-%#010llx]\n", start, start + size - 1);
159 return;
160 }
161
162 table->entries[x].addr = start;
163 table->entries[x].size = size;
164 table->entries[x].type = type;
165 table->nr_entries++;
166}
167
168void __init e820__range_add(u64 start, u64 size, enum e820_type type)
169{
170 __e820__range_add(e820_table, start, size, type);
171}
172
173static void __init e820_print_type(enum e820_type type)
174{
175 switch (type) {
176 case E820_TYPE_RAM: /* Fall through: */
177 case E820_TYPE_RESERVED_KERN: pr_cont("usable"); break;
178 case E820_TYPE_RESERVED: pr_cont("reserved"); break;
179 case E820_TYPE_ACPI: pr_cont("ACPI data"); break;
180 case E820_TYPE_NVS: pr_cont("ACPI NVS"); break;
181 case E820_TYPE_UNUSABLE: pr_cont("unusable"); break;
182 case E820_TYPE_PMEM: /* Fall through: */
183 case E820_TYPE_PRAM: pr_cont("persistent (type %u)", type); break;
184 default: pr_cont("type %u", type); break;
185 }
186}
187
188void __init e820__print_table(char *who)
189{
190 int i;
191
192 for (i = 0; i < e820_table->nr_entries; i++) {
193 pr_info("%s: [mem %#018Lx-%#018Lx] ", who,
194 e820_table->entries[i].addr,
195 e820_table->entries[i].addr + e820_table->entries[i].size - 1);
196
197 e820_print_type(e820_table->entries[i].type);
198 pr_cont("\n");
199 }
200}
201
202/*
203 * Sanitize an E820 map.
204 *
205 * Some E820 layouts include overlapping entries. The following
206 * replaces the original E820 map with a new one, removing overlaps,
207 * and resolving conflicting memory types in favor of highest
208 * numbered type.
209 *
210 * The input parameter 'entries' points to an array of 'struct
211 * e820_entry' which on entry has elements in the range [0, *nr_entries)
212 * valid, and which has space for up to max_nr_entries entries.
213 * On return, the resulting sanitized E820 map entries will be in
214 * overwritten in the same location, starting at 'entries'.
215 *
216 * The integer pointed to by nr_entries must be valid on entry (the
217 * current number of valid entries located at 'entries'). If the
218 * sanitizing succeeds the *nr_entries will be updated with the new
219 * number of valid entries (something no more than max_nr_entries).
220 *
221 * The return value from e820__update_table() is zero if it
222 * successfully 'sanitized' the map entries passed in, and is -1
223 * if it did nothing, which can happen if either of (1) it was
224 * only passed one map entry, or (2) any of the input map entries
225 * were invalid (start + size < start, meaning that the size was
226 * so big the described memory range wrapped around through zero.)
227 *
228 * Visually we're performing the following
229 * (1,2,3,4 = memory types)...
230 *
231 * Sample memory map (w/overlaps):
232 * ____22__________________
233 * ______________________4_
234 * ____1111________________
235 * _44_____________________
236 * 11111111________________
237 * ____________________33__
238 * ___________44___________
239 * __________33333_________
240 * ______________22________
241 * ___________________2222_
242 * _________111111111______
243 * _____________________11_
244 * _________________4______
245 *
246 * Sanitized equivalent (no overlap):
247 * 1_______________________
248 * _44_____________________
249 * ___1____________________
250 * ____22__________________
251 * ______11________________
252 * _________1______________
253 * __________3_____________
254 * ___________44___________
255 * _____________33_________
256 * _______________2________
257 * ________________1_______
258 * _________________4______
259 * ___________________2____
260 * ____________________33__
261 * ______________________4_
262 */
263struct change_member {
264 /* Pointer to the original entry: */
265 struct e820_entry *entry;
266 /* Address for this change point: */
267 unsigned long long addr;
268};
269
270static struct change_member change_point_list[2*E820_MAX_ENTRIES] __initdata;
271static struct change_member *change_point[2*E820_MAX_ENTRIES] __initdata;
272static struct e820_entry *overlap_list[E820_MAX_ENTRIES] __initdata;
273static struct e820_entry new_entries[E820_MAX_ENTRIES] __initdata;
274
275static int __init cpcompare(const void *a, const void *b)
276{
277 struct change_member * const *app = a, * const *bpp = b;
278 const struct change_member *ap = *app, *bp = *bpp;
279
280 /*
281 * Inputs are pointers to two elements of change_point[]. If their
282 * addresses are not equal, their difference dominates. If the addresses
283 * are equal, then consider one that represents the end of its region
284 * to be greater than one that does not.
285 */
286 if (ap->addr != bp->addr)
287 return ap->addr > bp->addr ? 1 : -1;
288
289 return (ap->addr != ap->entry->addr) - (bp->addr != bp->entry->addr);
290}
291
292int __init e820__update_table(struct e820_table *table)
293{
294 struct e820_entry *entries = table->entries;
295 u32 max_nr_entries = ARRAY_SIZE(table->entries);
296 enum e820_type current_type, last_type;
297 unsigned long long last_addr;
298 u32 new_nr_entries, overlap_entries;
299 u32 i, chg_idx, chg_nr;
300
301 /* If there's only one memory region, don't bother: */
302 if (table->nr_entries < 2)
303 return -1;
304
305 BUG_ON(table->nr_entries > max_nr_entries);
306
307 /* Bail out if we find any unreasonable addresses in the map: */
308 for (i = 0; i < table->nr_entries; i++) {
309 if (entries[i].addr + entries[i].size < entries[i].addr)
310 return -1;
311 }
312
313 /* Create pointers for initial change-point information (for sorting): */
314 for (i = 0; i < 2 * table->nr_entries; i++)
315 change_point[i] = &change_point_list[i];
316
317 /*
318 * Record all known change-points (starting and ending addresses),
319 * omitting empty memory regions:
320 */
321 chg_idx = 0;
322 for (i = 0; i < table->nr_entries; i++) {
323 if (entries[i].size != 0) {
324 change_point[chg_idx]->addr = entries[i].addr;
325 change_point[chg_idx++]->entry = &entries[i];
326 change_point[chg_idx]->addr = entries[i].addr + entries[i].size;
327 change_point[chg_idx++]->entry = &entries[i];
328 }
329 }
330 chg_nr = chg_idx;
331
332 /* Sort change-point list by memory addresses (low -> high): */
333 sort(change_point, chg_nr, sizeof(*change_point), cpcompare, NULL);
334
335 /* Create a new memory map, removing overlaps: */
336 overlap_entries = 0; /* Number of entries in the overlap table */
337 new_nr_entries = 0; /* Index for creating new map entries */
338 last_type = 0; /* Start with undefined memory type */
339 last_addr = 0; /* Start with 0 as last starting address */
340
341 /* Loop through change-points, determining effect on the new map: */
342 for (chg_idx = 0; chg_idx < chg_nr; chg_idx++) {
343 /* Keep track of all overlapping entries */
344 if (change_point[chg_idx]->addr == change_point[chg_idx]->entry->addr) {
345 /* Add map entry to overlap list (> 1 entry implies an overlap) */
346 overlap_list[overlap_entries++] = change_point[chg_idx]->entry;
347 } else {
348 /* Remove entry from list (order independent, so swap with last): */
349 for (i = 0; i < overlap_entries; i++) {
350 if (overlap_list[i] == change_point[chg_idx]->entry)
351 overlap_list[i] = overlap_list[overlap_entries-1];
352 }
353 overlap_entries--;
354 }
355 /*
356 * If there are overlapping entries, decide which
357 * "type" to use (larger value takes precedence --
358 * 1=usable, 2,3,4,4+=unusable)
359 */
360 current_type = 0;
361 for (i = 0; i < overlap_entries; i++) {
362 if (overlap_list[i]->type > current_type)
363 current_type = overlap_list[i]->type;
364 }
365
366 /* Continue building up new map based on this information: */
367 if (current_type != last_type || current_type == E820_TYPE_PRAM) {
368 if (last_type != 0) {
369 new_entries[new_nr_entries].size = change_point[chg_idx]->addr - last_addr;
370 /* Move forward only if the new size was non-zero: */
371 if (new_entries[new_nr_entries].size != 0)
372 /* No more space left for new entries? */
373 if (++new_nr_entries >= max_nr_entries)
374 break;
375 }
376 if (current_type != 0) {
377 new_entries[new_nr_entries].addr = change_point[chg_idx]->addr;
378 new_entries[new_nr_entries].type = current_type;
379 last_addr = change_point[chg_idx]->addr;
380 }
381 last_type = current_type;
382 }
383 }
384
385 /* Copy the new entries into the original location: */
386 memcpy(entries, new_entries, new_nr_entries*sizeof(*entries));
387 table->nr_entries = new_nr_entries;
388
389 return 0;
390}
391
392static int __init __append_e820_table(struct boot_e820_entry *entries, u32 nr_entries)
393{
394 struct boot_e820_entry *entry = entries;
395
396 while (nr_entries) {
397 u64 start = entry->addr;
398 u64 size = entry->size;
399 u64 end = start + size - 1;
400 u32 type = entry->type;
401
402 /* Ignore the entry on 64-bit overflow: */
403 if (start > end && likely(size))
404 return -1;
405
406 e820__range_add(start, size, type);
407
408 entry++;
409 nr_entries--;
410 }
411 return 0;
412}
413
414/*
415 * Copy the BIOS E820 map into a safe place.
416 *
417 * Sanity-check it while we're at it..
418 *
419 * If we're lucky and live on a modern system, the setup code
420 * will have given us a memory map that we can use to properly
421 * set up memory. If we aren't, we'll fake a memory map.
422 */
423static int __init append_e820_table(struct boot_e820_entry *entries, u32 nr_entries)
424{
425 /* Only one memory region (or negative)? Ignore it */
426 if (nr_entries < 2)
427 return -1;
428
429 return __append_e820_table(entries, nr_entries);
430}
431
432static u64 __init
433__e820__range_update(struct e820_table *table, u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
434{
435 u64 end;
436 unsigned int i;
437 u64 real_updated_size = 0;
438
439 BUG_ON(old_type == new_type);
440
441 if (size > (ULLONG_MAX - start))
442 size = ULLONG_MAX - start;
443
444 end = start + size;
445 printk(KERN_DEBUG "e820: update [mem %#010Lx-%#010Lx] ", start, end - 1);
446 e820_print_type(old_type);
447 pr_cont(" ==> ");
448 e820_print_type(new_type);
449 pr_cont("\n");
450
451 for (i = 0; i < table->nr_entries; i++) {
452 struct e820_entry *entry = &table->entries[i];
453 u64 final_start, final_end;
454 u64 entry_end;
455
456 if (entry->type != old_type)
457 continue;
458
459 entry_end = entry->addr + entry->size;
460
461 /* Completely covered by new range? */
462 if (entry->addr >= start && entry_end <= end) {
463 entry->type = new_type;
464 real_updated_size += entry->size;
465 continue;
466 }
467
468 /* New range is completely covered? */
469 if (entry->addr < start && entry_end > end) {
470 __e820__range_add(table, start, size, new_type);
471 __e820__range_add(table, end, entry_end - end, entry->type);
472 entry->size = start - entry->addr;
473 real_updated_size += size;
474 continue;
475 }
476
477 /* Partially covered: */
478 final_start = max(start, entry->addr);
479 final_end = min(end, entry_end);
480 if (final_start >= final_end)
481 continue;
482
483 __e820__range_add(table, final_start, final_end - final_start, new_type);
484
485 real_updated_size += final_end - final_start;
486
487 /*
488 * Left range could be head or tail, so need to update
489 * its size first:
490 */
491 entry->size -= final_end - final_start;
492 if (entry->addr < final_start)
493 continue;
494
495 entry->addr = final_end;
496 }
497 return real_updated_size;
498}
499
500u64 __init e820__range_update(u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
501{
502 return __e820__range_update(e820_table, start, size, old_type, new_type);
503}
504
505static u64 __init e820__range_update_kexec(u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
506{
507 return __e820__range_update(e820_table_kexec, start, size, old_type, new_type);
508}
509
510/* Remove a range of memory from the E820 table: */
511u64 __init e820__range_remove(u64 start, u64 size, enum e820_type old_type, bool check_type)
512{
513 int i;
514 u64 end;
515 u64 real_removed_size = 0;
516
517 if (size > (ULLONG_MAX - start))
518 size = ULLONG_MAX - start;
519
520 end = start + size;
521 printk(KERN_DEBUG "e820: remove [mem %#010Lx-%#010Lx] ", start, end - 1);
522 if (check_type)
523 e820_print_type(old_type);
524 pr_cont("\n");
525
526 for (i = 0; i < e820_table->nr_entries; i++) {
527 struct e820_entry *entry = &e820_table->entries[i];
528 u64 final_start, final_end;
529 u64 entry_end;
530
531 if (check_type && entry->type != old_type)
532 continue;
533
534 entry_end = entry->addr + entry->size;
535
536 /* Completely covered? */
537 if (entry->addr >= start && entry_end <= end) {
538 real_removed_size += entry->size;
539 memset(entry, 0, sizeof(*entry));
540 continue;
541 }
542
543 /* Is the new range completely covered? */
544 if (entry->addr < start && entry_end > end) {
545 e820__range_add(end, entry_end - end, entry->type);
546 entry->size = start - entry->addr;
547 real_removed_size += size;
548 continue;
549 }
550
551 /* Partially covered: */
552 final_start = max(start, entry->addr);
553 final_end = min(end, entry_end);
554 if (final_start >= final_end)
555 continue;
556
557 real_removed_size += final_end - final_start;
558
559 /*
560 * Left range could be head or tail, so need to update
561 * the size first:
562 */
563 entry->size -= final_end - final_start;
564 if (entry->addr < final_start)
565 continue;
566
567 entry->addr = final_end;
568 }
569 return real_removed_size;
570}
571
572void __init e820__update_table_print(void)
573{
574 if (e820__update_table(e820_table))
575 return;
576
577 pr_info("e820: modified physical RAM map:\n");
578 e820__print_table("modified");
579}
580
581static void __init e820__update_table_kexec(void)
582{
583 e820__update_table(e820_table_kexec);
584}
585
586#define MAX_GAP_END 0x100000000ull
587
588/*
589 * Search for a gap in the E820 memory space from 0 to MAX_GAP_END (4GB).
590 */
591static int __init e820_search_gap(unsigned long *gapstart, unsigned long *gapsize)
592{
593 unsigned long long last = MAX_GAP_END;
594 int i = e820_table->nr_entries;
595 int found = 0;
596
597 while (--i >= 0) {
598 unsigned long long start = e820_table->entries[i].addr;
599 unsigned long long end = start + e820_table->entries[i].size;
600
601 /*
602 * Since "last" is at most 4GB, we know we'll
603 * fit in 32 bits if this condition is true:
604 */
605 if (last > end) {
606 unsigned long gap = last - end;
607
608 if (gap >= *gapsize) {
609 *gapsize = gap;
610 *gapstart = end;
611 found = 1;
612 }
613 }
614 if (start < last)
615 last = start;
616 }
617 return found;
618}
619
620/*
621 * Search for the biggest gap in the low 32 bits of the E820
622 * memory space. We pass this space to the PCI subsystem, so
623 * that it can assign MMIO resources for hotplug or
624 * unconfigured devices in.
625 *
626 * Hopefully the BIOS let enough space left.
627 */
628__init void e820__setup_pci_gap(void)
629{
630 unsigned long gapstart, gapsize;
631 int found;
632
633 gapsize = 0x400000;
634 found = e820_search_gap(&gapstart, &gapsize);
635
636 if (!found) {
637#ifdef CONFIG_X86_64
638 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
639 pr_err(
640 "e820: Cannot find an available gap in the 32-bit address range\n"
641 "e820: PCI devices with unassigned 32-bit BARs may not work!\n");
642#else
643 gapstart = 0x10000000;
644#endif
645 }
646
647 /*
648 * e820__reserve_resources_late() protects stolen RAM already:
649 */
650 pci_mem_start = gapstart;
651
652 pr_info("e820: [mem %#010lx-%#010lx] available for PCI devices\n", gapstart, gapstart + gapsize - 1);
653}
654
655/*
656 * Called late during init, in free_initmem().
657 *
658 * Initial e820_table and e820_table_kexec are largish __initdata arrays.
659 *
660 * Copy them to a (usually much smaller) dynamically allocated area that is
661 * sized precisely after the number of e820 entries.
662 *
663 * This is done after we've performed all the fixes and tweaks to the tables.
664 * All functions which modify them are __init functions, which won't exist
665 * after free_initmem().
666 */
667__init void e820__reallocate_tables(void)
668{
669 struct e820_table *n;
670 int size;
671
672 size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table->nr_entries;
673 n = kmalloc(size, GFP_KERNEL);
674 BUG_ON(!n);
675 memcpy(n, e820_table, size);
676 e820_table = n;
677
678 size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_kexec->nr_entries;
679 n = kmalloc(size, GFP_KERNEL);
680 BUG_ON(!n);
681 memcpy(n, e820_table_kexec, size);
682 e820_table_kexec = n;
683
684 size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_firmware->nr_entries;
685 n = kmalloc(size, GFP_KERNEL);
686 BUG_ON(!n);
687 memcpy(n, e820_table_firmware, size);
688 e820_table_firmware = n;
689}
690
691/*
692 * Because of the small fixed size of struct boot_params, only the first
693 * 128 E820 memory entries are passed to the kernel via boot_params.e820_table,
694 * the remaining (if any) entries are passed via the SETUP_E820_EXT node of
695 * struct setup_data, which is parsed here.
696 */
697void __init e820__memory_setup_extended(u64 phys_addr, u32 data_len)
698{
699 int entries;
700 struct boot_e820_entry *extmap;
701 struct setup_data *sdata;
702
703 sdata = early_memremap(phys_addr, data_len);
704 entries = sdata->len / sizeof(*extmap);
705 extmap = (struct boot_e820_entry *)(sdata->data);
706
707 __append_e820_table(extmap, entries);
708 e820__update_table(e820_table);
709
710 memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec));
711 memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
712
713 early_memunmap(sdata, data_len);
714 pr_info("e820: extended physical RAM map:\n");
715 e820__print_table("extended");
716}
717
718/*
719 * Find the ranges of physical addresses that do not correspond to
720 * E820 RAM areas and register the corresponding pages as 'nosave' for
721 * hibernation (32-bit) or software suspend and suspend to RAM (64-bit).
722 *
723 * This function requires the E820 map to be sorted and without any
724 * overlapping entries.
725 */
726void __init e820__register_nosave_regions(unsigned long limit_pfn)
727{
728 int i;
729 unsigned long pfn = 0;
730
731 for (i = 0; i < e820_table->nr_entries; i++) {
732 struct e820_entry *entry = &e820_table->entries[i];
733
734 if (pfn < PFN_UP(entry->addr))
735 register_nosave_region(pfn, PFN_UP(entry->addr));
736
737 pfn = PFN_DOWN(entry->addr + entry->size);
738
739 if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
740 register_nosave_region(PFN_UP(entry->addr), pfn);
741
742 if (pfn >= limit_pfn)
743 break;
744 }
745}
746
747#ifdef CONFIG_ACPI
748/*
749 * Register ACPI NVS memory regions, so that we can save/restore them during
750 * hibernation and the subsequent resume:
751 */
752static int __init e820__register_nvs_regions(void)
753{
754 int i;
755
756 for (i = 0; i < e820_table->nr_entries; i++) {
757 struct e820_entry *entry = &e820_table->entries[i];
758
759 if (entry->type == E820_TYPE_NVS)
760 acpi_nvs_register(entry->addr, entry->size);
761 }
762
763 return 0;
764}
765core_initcall(e820__register_nvs_regions);
766#endif
767
768/*
769 * Allocate the requested number of bytes with the requsted alignment
770 * and return (the physical address) to the caller. Also register this
771 * range in the 'kexec' E820 table as a reserved range.
772 *
773 * This allows kexec to fake a new mptable, as if it came from the real
774 * system.
775 */
776u64 __init e820__memblock_alloc_reserved(u64 size, u64 align)
777{
778 u64 addr;
779
780 addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
781 if (addr) {
782 e820__range_update_kexec(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED);
783 pr_info("e820: update e820_table_kexec for e820__memblock_alloc_reserved()\n");
784 e820__update_table_kexec();
785 }
786
787 return addr;
788}
789
790#ifdef CONFIG_X86_32
791# ifdef CONFIG_X86_PAE
792# define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
793# else
794# define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
795# endif
796#else /* CONFIG_X86_32 */
797# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
798#endif
799
800/*
801 * Find the highest page frame number we have available
802 */
803static unsigned long __init e820_end_pfn(unsigned long limit_pfn, enum e820_type type)
804{
805 int i;
806 unsigned long last_pfn = 0;
807 unsigned long max_arch_pfn = MAX_ARCH_PFN;
808
809 for (i = 0; i < e820_table->nr_entries; i++) {
810 struct e820_entry *entry = &e820_table->entries[i];
811 unsigned long start_pfn;
812 unsigned long end_pfn;
813
814 if (entry->type != type)
815 continue;
816
817 start_pfn = entry->addr >> PAGE_SHIFT;
818 end_pfn = (entry->addr + entry->size) >> PAGE_SHIFT;
819
820 if (start_pfn >= limit_pfn)
821 continue;
822 if (end_pfn > limit_pfn) {
823 last_pfn = limit_pfn;
824 break;
825 }
826 if (end_pfn > last_pfn)
827 last_pfn = end_pfn;
828 }
829
830 if (last_pfn > max_arch_pfn)
831 last_pfn = max_arch_pfn;
832
833 pr_info("e820: last_pfn = %#lx max_arch_pfn = %#lx\n",
834 last_pfn, max_arch_pfn);
835 return last_pfn;
836}
837
838unsigned long __init e820__end_of_ram_pfn(void)
839{
840 return e820_end_pfn(MAX_ARCH_PFN, E820_TYPE_RAM);
841}
842
843unsigned long __init e820__end_of_low_ram_pfn(void)
844{
845 return e820_end_pfn(1UL << (32 - PAGE_SHIFT), E820_TYPE_RAM);
846}
847
848static void __init early_panic(char *msg)
849{
850 early_printk(msg);
851 panic(msg);
852}
853
854static int userdef __initdata;
855
856/* The "mem=nopentium" boot option disables 4MB page tables on 32-bit kernels: */
857static int __init parse_memopt(char *p)
858{
859 u64 mem_size;
860
861 if (!p)
862 return -EINVAL;
863
864 if (!strcmp(p, "nopentium")) {
865#ifdef CONFIG_X86_32
866 setup_clear_cpu_cap(X86_FEATURE_PSE);
867 return 0;
868#else
869 pr_warn("mem=nopentium ignored! (only supported on x86_32)\n");
870 return -EINVAL;
871#endif
872 }
873
874 userdef = 1;
875 mem_size = memparse(p, &p);
876
877 /* Don't remove all memory when getting "mem={invalid}" parameter: */
878 if (mem_size == 0)
879 return -EINVAL;
880
881 e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
882
883 return 0;
884}
885early_param("mem", parse_memopt);
886
887static int __init parse_memmap_one(char *p)
888{
889 char *oldp;
890 u64 start_at, mem_size;
891
892 if (!p)
893 return -EINVAL;
894
895 if (!strncmp(p, "exactmap", 8)) {
896#ifdef CONFIG_CRASH_DUMP
897 /*
898 * If we are doing a crash dump, we still need to know
899 * the real memory size before the original memory map is
900 * reset.
901 */
902 saved_max_pfn = e820__end_of_ram_pfn();
903#endif
904 e820_table->nr_entries = 0;
905 userdef = 1;
906 return 0;
907 }
908
909 oldp = p;
910 mem_size = memparse(p, &p);
911 if (p == oldp)
912 return -EINVAL;
913
914 userdef = 1;
915 if (*p == '@') {
916 start_at = memparse(p+1, &p);
917 e820__range_add(start_at, mem_size, E820_TYPE_RAM);
918 } else if (*p == '#') {
919 start_at = memparse(p+1, &p);
920 e820__range_add(start_at, mem_size, E820_TYPE_ACPI);
921 } else if (*p == '$') {
922 start_at = memparse(p+1, &p);
923 e820__range_add(start_at, mem_size, E820_TYPE_RESERVED);
924 } else if (*p == '!') {
925 start_at = memparse(p+1, &p);
926 e820__range_add(start_at, mem_size, E820_TYPE_PRAM);
927 } else if (*p == '%') {
928 enum e820_type from = 0, to = 0;
929
930 start_at = memparse(p + 1, &p);
931 if (*p == '-')
932 from = simple_strtoull(p + 1, &p, 0);
933 if (*p == '+')
934 to = simple_strtoull(p + 1, &p, 0);
935 if (*p != '\0')
936 return -EINVAL;
937 if (from && to)
938 e820__range_update(start_at, mem_size, from, to);
939 else if (to)
940 e820__range_add(start_at, mem_size, to);
941 else if (from)
942 e820__range_remove(start_at, mem_size, from, 1);
943 else
944 e820__range_remove(start_at, mem_size, 0, 0);
945 } else {
946 e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
947 }
948
949 return *p == '\0' ? 0 : -EINVAL;
950}
951
952static int __init parse_memmap_opt(char *str)
953{
954 while (str) {
955 char *k = strchr(str, ',');
956
957 if (k)
958 *k++ = 0;
959
960 parse_memmap_one(str);
961 str = k;
962 }
963
964 return 0;
965}
966early_param("memmap", parse_memmap_opt);
967
968/*
969 * Reserve all entries from the bootloader's extensible data nodes list,
970 * because if present we are going to use it later on to fetch e820
971 * entries from it:
972 */
973void __init e820__reserve_setup_data(void)
974{
975 struct setup_data *data;
976 u64 pa_data;
977
978 pa_data = boot_params.hdr.setup_data;
979 if (!pa_data)
980 return;
981
982 while (pa_data) {
983 data = early_memremap(pa_data, sizeof(*data));
984 e820__range_update(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
985 e820__range_update_kexec(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
986 pa_data = data->next;
987 early_memunmap(data, sizeof(*data));
988 }
989
990 e820__update_table(e820_table);
991 e820__update_table(e820_table_kexec);
992
993 pr_info("extended physical RAM map:\n");
994 e820__print_table("reserve setup_data");
995}
996
997/*
998 * Called after parse_early_param(), after early parameters (such as mem=)
999 * have been processed, in which case we already have an E820 table filled in
1000 * via the parameter callback function(s), but it's not sorted and printed yet:
1001 */
1002void __init e820__finish_early_params(void)
1003{
1004 if (userdef) {
1005 if (e820__update_table(e820_table) < 0)
1006 early_panic("Invalid user supplied memory map");
1007
1008 pr_info("e820: user-defined physical RAM map:\n");
1009 e820__print_table("user");
1010 }
1011}
1012
1013static const char *__init e820_type_to_string(struct e820_entry *entry)
1014{
1015 switch (entry->type) {
1016 case E820_TYPE_RESERVED_KERN: /* Fall-through: */
1017 case E820_TYPE_RAM: return "System RAM";
1018 case E820_TYPE_ACPI: return "ACPI Tables";
1019 case E820_TYPE_NVS: return "ACPI Non-volatile Storage";
1020 case E820_TYPE_UNUSABLE: return "Unusable memory";
1021 case E820_TYPE_PRAM: return "Persistent Memory (legacy)";
1022 case E820_TYPE_PMEM: return "Persistent Memory";
1023 case E820_TYPE_RESERVED: return "Reserved";
1024 default: return "Unknown E820 type";
1025 }
1026}
1027
1028static unsigned long __init e820_type_to_iomem_type(struct e820_entry *entry)
1029{
1030 switch (entry->type) {
1031 case E820_TYPE_RESERVED_KERN: /* Fall-through: */
1032 case E820_TYPE_RAM: return IORESOURCE_SYSTEM_RAM;
1033 case E820_TYPE_ACPI: /* Fall-through: */
1034 case E820_TYPE_NVS: /* Fall-through: */
1035 case E820_TYPE_UNUSABLE: /* Fall-through: */
1036 case E820_TYPE_PRAM: /* Fall-through: */
1037 case E820_TYPE_PMEM: /* Fall-through: */
1038 case E820_TYPE_RESERVED: /* Fall-through: */
1039 default: return IORESOURCE_MEM;
1040 }
1041}
1042
1043static unsigned long __init e820_type_to_iores_desc(struct e820_entry *entry)
1044{
1045 switch (entry->type) {
1046 case E820_TYPE_ACPI: return IORES_DESC_ACPI_TABLES;
1047 case E820_TYPE_NVS: return IORES_DESC_ACPI_NV_STORAGE;
1048 case E820_TYPE_PMEM: return IORES_DESC_PERSISTENT_MEMORY;
1049 case E820_TYPE_PRAM: return IORES_DESC_PERSISTENT_MEMORY_LEGACY;
1050 case E820_TYPE_RESERVED_KERN: /* Fall-through: */
1051 case E820_TYPE_RAM: /* Fall-through: */
1052 case E820_TYPE_UNUSABLE: /* Fall-through: */
1053 case E820_TYPE_RESERVED: /* Fall-through: */
1054 default: return IORES_DESC_NONE;
1055 }
1056}
1057
1058static bool __init do_mark_busy(enum e820_type type, struct resource *res)
1059{
1060 /* this is the legacy bios/dos rom-shadow + mmio region */
1061 if (res->start < (1ULL<<20))
1062 return true;
1063
1064 /*
1065 * Treat persistent memory like device memory, i.e. reserve it
1066 * for exclusive use of a driver
1067 */
1068 switch (type) {
1069 case E820_TYPE_RESERVED:
1070 case E820_TYPE_PRAM:
1071 case E820_TYPE_PMEM:
1072 return false;
1073 case E820_TYPE_RESERVED_KERN:
1074 case E820_TYPE_RAM:
1075 case E820_TYPE_ACPI:
1076 case E820_TYPE_NVS:
1077 case E820_TYPE_UNUSABLE:
1078 default:
1079 return true;
1080 }
1081}
1082
1083/*
1084 * Mark E820 reserved areas as busy for the resource manager:
1085 */
1086
1087static struct resource __initdata *e820_res;
1088
1089void __init e820__reserve_resources(void)
1090{
1091 int i;
1092 struct resource *res;
1093 u64 end;
1094
1095 res = alloc_bootmem(sizeof(*res) * e820_table->nr_entries);
1096 e820_res = res;
1097
1098 for (i = 0; i < e820_table->nr_entries; i++) {
1099 struct e820_entry *entry = e820_table->entries + i;
1100
1101 end = entry->addr + entry->size - 1;
1102 if (end != (resource_size_t)end) {
1103 res++;
1104 continue;
1105 }
1106 res->start = entry->addr;
1107 res->end = end;
1108 res->name = e820_type_to_string(entry);
1109 res->flags = e820_type_to_iomem_type(entry);
1110 res->desc = e820_type_to_iores_desc(entry);
1111
1112 /*
1113 * Don't register the region that could be conflicted with
1114 * PCI device BAR resources and insert them later in
1115 * pcibios_resource_survey():
1116 */
1117 if (do_mark_busy(entry->type, res)) {
1118 res->flags |= IORESOURCE_BUSY;
1119 insert_resource(&iomem_resource, res);
1120 }
1121 res++;
1122 }
1123
1124 /* Expose the bootloader-provided memory layout to the sysfs. */
1125 for (i = 0; i < e820_table_firmware->nr_entries; i++) {
1126 struct e820_entry *entry = e820_table_firmware->entries + i;
1127
1128 firmware_map_add_early(entry->addr, entry->addr + entry->size, e820_type_to_string(entry));
1129 }
1130}
1131
1132/*
1133 * How much should we pad the end of RAM, depending on where it is?
1134 */
1135static unsigned long __init ram_alignment(resource_size_t pos)
1136{
1137 unsigned long mb = pos >> 20;
1138
1139 /* To 64kB in the first megabyte */
1140 if (!mb)
1141 return 64*1024;
1142
1143 /* To 1MB in the first 16MB */
1144 if (mb < 16)
1145 return 1024*1024;
1146
1147 /* To 64MB for anything above that */
1148 return 64*1024*1024;
1149}
1150
1151#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
1152
1153void __init e820__reserve_resources_late(void)
1154{
1155 int i;
1156 struct resource *res;
1157
1158 res = e820_res;
1159 for (i = 0; i < e820_table->nr_entries; i++) {
1160 if (!res->parent && res->end)
1161 insert_resource_expand_to_fit(&iomem_resource, res);
1162 res++;
1163 }
1164
1165 /*
1166 * Try to bump up RAM regions to reasonable boundaries, to
1167 * avoid stolen RAM:
1168 */
1169 for (i = 0; i < e820_table->nr_entries; i++) {
1170 struct e820_entry *entry = &e820_table->entries[i];
1171 u64 start, end;
1172
1173 if (entry->type != E820_TYPE_RAM)
1174 continue;
1175
1176 start = entry->addr + entry->size;
1177 end = round_up(start, ram_alignment(start)) - 1;
1178 if (end > MAX_RESOURCE_SIZE)
1179 end = MAX_RESOURCE_SIZE;
1180 if (start >= end)
1181 continue;
1182
1183 printk(KERN_DEBUG "e820: reserve RAM buffer [mem %#010llx-%#010llx]\n", start, end);
1184 reserve_region_with_split(&iomem_resource, start, end, "RAM buffer");
1185 }
1186}
1187
1188/*
1189 * Pass the firmware (bootloader) E820 map to the kernel and process it:
1190 */
1191char *__init e820__memory_setup_default(void)
1192{
1193 char *who = "BIOS-e820";
1194
1195 /*
1196 * Try to copy the BIOS-supplied E820-map.
1197 *
1198 * Otherwise fake a memory map; one section from 0k->640k,
1199 * the next section from 1mb->appropriate_mem_k
1200 */
1201 if (append_e820_table(boot_params.e820_table, boot_params.e820_entries) < 0) {
1202 u64 mem_size;
1203
1204 /* Compare results from other methods and take the one that gives more RAM: */
1205 if (boot_params.alt_mem_k < boot_params.screen_info.ext_mem_k) {
1206 mem_size = boot_params.screen_info.ext_mem_k;
1207 who = "BIOS-88";
1208 } else {
1209 mem_size = boot_params.alt_mem_k;
1210 who = "BIOS-e801";
1211 }
1212
1213 e820_table->nr_entries = 0;
1214 e820__range_add(0, LOWMEMSIZE(), E820_TYPE_RAM);
1215 e820__range_add(HIGH_MEMORY, mem_size << 10, E820_TYPE_RAM);
1216 }
1217
1218 /* We just appended a lot of ranges, sanitize the table: */
1219 e820__update_table(e820_table);
1220
1221 return who;
1222}
1223
1224/*
1225 * Calls e820__memory_setup_default() in essence to pick up the firmware/bootloader
1226 * E820 map - with an optional platform quirk available for virtual platforms
1227 * to override this method of boot environment processing:
1228 */
1229void __init e820__memory_setup(void)
1230{
1231 char *who;
1232
1233 /* This is a firmware interface ABI - make sure we don't break it: */
1234 BUILD_BUG_ON(sizeof(struct boot_e820_entry) != 20);
1235
1236 who = x86_init.resources.memory_setup();
1237
1238 memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec));
1239 memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
1240
1241 pr_info("e820: BIOS-provided physical RAM map:\n");
1242 e820__print_table(who);
1243}
1244
1245void __init e820__memblock_setup(void)
1246{
1247 int i;
1248 u64 end;
1249
1250 /*
1251 * The bootstrap memblock region count maximum is 128 entries
1252 * (INIT_MEMBLOCK_REGIONS), but EFI might pass us more E820 entries
1253 * than that - so allow memblock resizing.
1254 *
1255 * This is safe, because this call happens pretty late during x86 setup,
1256 * so we know about reserved memory regions already. (This is important
1257 * so that memblock resizing does no stomp over reserved areas.)
1258 */
1259 memblock_allow_resize();
1260
1261 for (i = 0; i < e820_table->nr_entries; i++) {
1262 struct e820_entry *entry = &e820_table->entries[i];
1263
1264 end = entry->addr + entry->size;
1265 if (end != (resource_size_t)end)
1266 continue;
1267
1268 if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
1269 continue;
1270
1271 memblock_add(entry->addr, entry->size);
1272 }
1273
1274 /* Throw away partial pages: */
1275 memblock_trim_memory(PAGE_SIZE);
1276
1277 memblock_dump_all();
1278}
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 */
43static struct e820map initial_e820 __initdata;
44static struct e820map initial_e820_saved __initdata;
45struct e820map *e820 __refdata = &initial_e820;
46struct e820map *e820_saved __refdata = &initial_e820_saved;
47
48/* For PCI or other memory-mapped resources */
49unsigned long pci_mem_start = 0xaeedbabe;
50#ifdef CONFIG_PCI
51EXPORT_SYMBOL(pci_mem_start);
52#endif
53
54/*
55 * This function checks if any part of the range <start,end> is mapped
56 * with type.
57 */
58int
59e820_any_mapped(u64 start, u64 end, unsigned type)
60{
61 int i;
62
63 for (i = 0; i < e820->nr_map; i++) {
64 struct e820entry *ei = &e820->map[i];
65
66 if (type && ei->type != type)
67 continue;
68 if (ei->addr >= end || ei->addr + ei->size <= start)
69 continue;
70 return 1;
71 }
72 return 0;
73}
74EXPORT_SYMBOL_GPL(e820_any_mapped);
75
76/*
77 * This function checks if the entire range <start,end> is mapped with type.
78 *
79 * Note: this function only works correct if the e820 table is sorted and
80 * not-overlapping, which is the case
81 */
82int __init e820_all_mapped(u64 start, u64 end, unsigned type)
83{
84 int i;
85
86 for (i = 0; i < e820->nr_map; i++) {
87 struct e820entry *ei = &e820->map[i];
88
89 if (type && ei->type != type)
90 continue;
91 /* is the region (part) in overlap with the current region ?*/
92 if (ei->addr >= end || ei->addr + ei->size <= start)
93 continue;
94
95 /* if the region is at the beginning of <start,end> we move
96 * start to the end of the region since it's ok until there
97 */
98 if (ei->addr <= start)
99 start = ei->addr + ei->size;
100 /*
101 * if start is now at or beyond end, we're done, full
102 * coverage
103 */
104 if (start >= end)
105 return 1;
106 }
107 return 0;
108}
109
110/*
111 * Add a memory region to the kernel e820 map.
112 */
113static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
114 int type)
115{
116 int x = e820x->nr_map;
117
118 if (x >= ARRAY_SIZE(e820x->map)) {
119 printk(KERN_ERR "e820: too many entries; ignoring [mem %#010llx-%#010llx]\n",
120 (unsigned long long) start,
121 (unsigned long long) (start + size - 1));
122 return;
123 }
124
125 e820x->map[x].addr = start;
126 e820x->map[x].size = size;
127 e820x->map[x].type = type;
128 e820x->nr_map++;
129}
130
131void __init e820_add_region(u64 start, u64 size, int type)
132{
133 __e820_add_region(e820, start, size, type);
134}
135
136static void __init e820_print_type(u32 type)
137{
138 switch (type) {
139 case E820_RAM:
140 case E820_RESERVED_KERN:
141 printk(KERN_CONT "usable");
142 break;
143 case E820_RESERVED:
144 printk(KERN_CONT "reserved");
145 break;
146 case E820_ACPI:
147 printk(KERN_CONT "ACPI data");
148 break;
149 case E820_NVS:
150 printk(KERN_CONT "ACPI NVS");
151 break;
152 case E820_UNUSABLE:
153 printk(KERN_CONT "unusable");
154 break;
155 case E820_PMEM:
156 case E820_PRAM:
157 printk(KERN_CONT "persistent (type %u)", type);
158 break;
159 default:
160 printk(KERN_CONT "type %u", type);
161 break;
162 }
163}
164
165void __init e820_print_map(char *who)
166{
167 int i;
168
169 for (i = 0; i < e820->nr_map; i++) {
170 printk(KERN_INFO "%s: [mem %#018Lx-%#018Lx] ", who,
171 (unsigned long long) e820->map[i].addr,
172 (unsigned long long)
173 (e820->map[i].addr + e820->map[i].size - 1));
174 e820_print_type(e820->map[i].type);
175 printk(KERN_CONT "\n");
176 }
177}
178
179/*
180 * Sanitize the BIOS e820 map.
181 *
182 * Some e820 responses include overlapping entries. The following
183 * replaces the original e820 map with a new one, removing overlaps,
184 * and resolving conflicting memory types in favor of highest
185 * numbered type.
186 *
187 * The input parameter biosmap points to an array of 'struct
188 * e820entry' which on entry has elements in the range [0, *pnr_map)
189 * valid, and which has space for up to max_nr_map entries.
190 * On return, the resulting sanitized e820 map entries will be in
191 * overwritten in the same location, starting at biosmap.
192 *
193 * The integer pointed to by pnr_map must be valid on entry (the
194 * current number of valid entries located at biosmap). If the
195 * sanitizing succeeds the *pnr_map will be updated with the new
196 * number of valid entries (something no more than max_nr_map).
197 *
198 * The return value from sanitize_e820_map() is zero if it
199 * successfully 'sanitized' the map entries passed in, and is -1
200 * if it did nothing, which can happen if either of (1) it was
201 * only passed one map entry, or (2) any of the input map entries
202 * were invalid (start + size < start, meaning that the size was
203 * so big the described memory range wrapped around through zero.)
204 *
205 * Visually we're performing the following
206 * (1,2,3,4 = memory types)...
207 *
208 * Sample memory map (w/overlaps):
209 * ____22__________________
210 * ______________________4_
211 * ____1111________________
212 * _44_____________________
213 * 11111111________________
214 * ____________________33__
215 * ___________44___________
216 * __________33333_________
217 * ______________22________
218 * ___________________2222_
219 * _________111111111______
220 * _____________________11_
221 * _________________4______
222 *
223 * Sanitized equivalent (no overlap):
224 * 1_______________________
225 * _44_____________________
226 * ___1____________________
227 * ____22__________________
228 * ______11________________
229 * _________1______________
230 * __________3_____________
231 * ___________44___________
232 * _____________33_________
233 * _______________2________
234 * ________________1_______
235 * _________________4______
236 * ___________________2____
237 * ____________________33__
238 * ______________________4_
239 */
240struct change_member {
241 struct e820entry *pbios; /* pointer to original bios entry */
242 unsigned long long addr; /* address for this change point */
243};
244
245static int __init cpcompare(const void *a, const void *b)
246{
247 struct change_member * const *app = a, * const *bpp = b;
248 const struct change_member *ap = *app, *bp = *bpp;
249
250 /*
251 * Inputs are pointers to two elements of change_point[]. If their
252 * addresses are unequal, their difference dominates. If the addresses
253 * are equal, then consider one that represents the end of its region
254 * to be greater than one that does not.
255 */
256 if (ap->addr != bp->addr)
257 return ap->addr > bp->addr ? 1 : -1;
258
259 return (ap->addr != ap->pbios->addr) - (bp->addr != bp->pbios->addr);
260}
261
262int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
263 u32 *pnr_map)
264{
265 static struct change_member change_point_list[2*E820_X_MAX] __initdata;
266 static struct change_member *change_point[2*E820_X_MAX] __initdata;
267 static struct e820entry *overlap_list[E820_X_MAX] __initdata;
268 static struct e820entry new_bios[E820_X_MAX] __initdata;
269 unsigned long current_type, last_type;
270 unsigned long long last_addr;
271 int chgidx;
272 int overlap_entries;
273 int new_bios_entry;
274 int old_nr, new_nr, chg_nr;
275 int i;
276
277 /* if there's only one memory region, don't bother */
278 if (*pnr_map < 2)
279 return -1;
280
281 old_nr = *pnr_map;
282 BUG_ON(old_nr > max_nr_map);
283
284 /* bail out if we find any unreasonable addresses in bios map */
285 for (i = 0; i < old_nr; i++)
286 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
287 return -1;
288
289 /* create pointers for initial change-point information (for sorting) */
290 for (i = 0; i < 2 * old_nr; i++)
291 change_point[i] = &change_point_list[i];
292
293 /* record all known change-points (starting and ending addresses),
294 omitting those that are for empty memory regions */
295 chgidx = 0;
296 for (i = 0; i < old_nr; i++) {
297 if (biosmap[i].size != 0) {
298 change_point[chgidx]->addr = biosmap[i].addr;
299 change_point[chgidx++]->pbios = &biosmap[i];
300 change_point[chgidx]->addr = biosmap[i].addr +
301 biosmap[i].size;
302 change_point[chgidx++]->pbios = &biosmap[i];
303 }
304 }
305 chg_nr = chgidx;
306
307 /* sort change-point list by memory addresses (low -> high) */
308 sort(change_point, chg_nr, sizeof *change_point, cpcompare, NULL);
309
310 /* create a new bios memory map, removing overlaps */
311 overlap_entries = 0; /* number of entries in the overlap table */
312 new_bios_entry = 0; /* index for creating new bios map entries */
313 last_type = 0; /* start with undefined memory type */
314 last_addr = 0; /* start with 0 as last starting address */
315
316 /* loop through change-points, determining affect on the new bios map */
317 for (chgidx = 0; chgidx < chg_nr; chgidx++) {
318 /* keep track of all overlapping bios entries */
319 if (change_point[chgidx]->addr ==
320 change_point[chgidx]->pbios->addr) {
321 /*
322 * add map entry to overlap list (> 1 entry
323 * implies an overlap)
324 */
325 overlap_list[overlap_entries++] =
326 change_point[chgidx]->pbios;
327 } else {
328 /*
329 * remove entry from list (order independent,
330 * so swap with last)
331 */
332 for (i = 0; i < overlap_entries; i++) {
333 if (overlap_list[i] ==
334 change_point[chgidx]->pbios)
335 overlap_list[i] =
336 overlap_list[overlap_entries-1];
337 }
338 overlap_entries--;
339 }
340 /*
341 * if there are overlapping entries, decide which
342 * "type" to use (larger value takes precedence --
343 * 1=usable, 2,3,4,4+=unusable)
344 */
345 current_type = 0;
346 for (i = 0; i < overlap_entries; i++)
347 if (overlap_list[i]->type > current_type)
348 current_type = overlap_list[i]->type;
349 /*
350 * continue building up new bios map based on this
351 * information
352 */
353 if (current_type != last_type || current_type == E820_PRAM) {
354 if (last_type != 0) {
355 new_bios[new_bios_entry].size =
356 change_point[chgidx]->addr - last_addr;
357 /*
358 * move forward only if the new size
359 * was non-zero
360 */
361 if (new_bios[new_bios_entry].size != 0)
362 /*
363 * no more space left for new
364 * bios entries ?
365 */
366 if (++new_bios_entry >= max_nr_map)
367 break;
368 }
369 if (current_type != 0) {
370 new_bios[new_bios_entry].addr =
371 change_point[chgidx]->addr;
372 new_bios[new_bios_entry].type = current_type;
373 last_addr = change_point[chgidx]->addr;
374 }
375 last_type = current_type;
376 }
377 }
378 /* retain count for new bios entries */
379 new_nr = new_bios_entry;
380
381 /* copy new bios mapping into original location */
382 memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
383 *pnr_map = new_nr;
384
385 return 0;
386}
387
388static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
389{
390 while (nr_map) {
391 u64 start = biosmap->addr;
392 u64 size = biosmap->size;
393 u64 end = start + size - 1;
394 u32 type = biosmap->type;
395
396 /* Overflow in 64 bits? Ignore the memory map. */
397 if (start > end && likely(size))
398 return -1;
399
400 e820_add_region(start, size, type);
401
402 biosmap++;
403 nr_map--;
404 }
405 return 0;
406}
407
408/*
409 * Copy the BIOS e820 map into a safe place.
410 *
411 * Sanity-check it while we're at it..
412 *
413 * If we're lucky and live on a modern system, the setup code
414 * will have given us a memory map that we can use to properly
415 * set up memory. If we aren't, we'll fake a memory map.
416 */
417static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
418{
419 /* Only one memory region (or negative)? Ignore it */
420 if (nr_map < 2)
421 return -1;
422
423 return __append_e820_map(biosmap, nr_map);
424}
425
426static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
427 u64 size, unsigned old_type,
428 unsigned new_type)
429{
430 u64 end;
431 unsigned int i;
432 u64 real_updated_size = 0;
433
434 BUG_ON(old_type == new_type);
435
436 if (size > (ULLONG_MAX - start))
437 size = ULLONG_MAX - start;
438
439 end = start + size;
440 printk(KERN_DEBUG "e820: update [mem %#010Lx-%#010Lx] ",
441 (unsigned long long) start, (unsigned long long) (end - 1));
442 e820_print_type(old_type);
443 printk(KERN_CONT " ==> ");
444 e820_print_type(new_type);
445 printk(KERN_CONT "\n");
446
447 for (i = 0; i < e820x->nr_map; i++) {
448 struct e820entry *ei = &e820x->map[i];
449 u64 final_start, final_end;
450 u64 ei_end;
451
452 if (ei->type != old_type)
453 continue;
454
455 ei_end = ei->addr + ei->size;
456 /* totally covered by new range? */
457 if (ei->addr >= start && ei_end <= end) {
458 ei->type = new_type;
459 real_updated_size += ei->size;
460 continue;
461 }
462
463 /* new range is totally covered? */
464 if (ei->addr < start && ei_end > end) {
465 __e820_add_region(e820x, start, size, new_type);
466 __e820_add_region(e820x, end, ei_end - end, ei->type);
467 ei->size = start - ei->addr;
468 real_updated_size += size;
469 continue;
470 }
471
472 /* partially covered */
473 final_start = max(start, ei->addr);
474 final_end = min(end, ei_end);
475 if (final_start >= final_end)
476 continue;
477
478 __e820_add_region(e820x, final_start, final_end - final_start,
479 new_type);
480
481 real_updated_size += final_end - final_start;
482
483 /*
484 * left range could be head or tail, so need to update
485 * size at first.
486 */
487 ei->size -= final_end - final_start;
488 if (ei->addr < final_start)
489 continue;
490 ei->addr = final_end;
491 }
492 return real_updated_size;
493}
494
495u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
496 unsigned new_type)
497{
498 return __e820_update_range(e820, start, size, old_type, new_type);
499}
500
501static u64 __init e820_update_range_saved(u64 start, u64 size,
502 unsigned old_type, unsigned new_type)
503{
504 return __e820_update_range(e820_saved, start, size, old_type,
505 new_type);
506}
507
508/* make e820 not cover the range */
509u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
510 int checktype)
511{
512 int i;
513 u64 end;
514 u64 real_removed_size = 0;
515
516 if (size > (ULLONG_MAX - start))
517 size = ULLONG_MAX - start;
518
519 end = start + size;
520 printk(KERN_DEBUG "e820: remove [mem %#010Lx-%#010Lx] ",
521 (unsigned long long) start, (unsigned long long) (end - 1));
522 if (checktype)
523 e820_print_type(old_type);
524 printk(KERN_CONT "\n");
525
526 for (i = 0; i < e820->nr_map; i++) {
527 struct e820entry *ei = &e820->map[i];
528 u64 final_start, final_end;
529 u64 ei_end;
530
531 if (checktype && ei->type != old_type)
532 continue;
533
534 ei_end = ei->addr + ei->size;
535 /* totally covered? */
536 if (ei->addr >= start && ei_end <= end) {
537 real_removed_size += ei->size;
538 memset(ei, 0, sizeof(struct e820entry));
539 continue;
540 }
541
542 /* new range is totally covered? */
543 if (ei->addr < start && ei_end > end) {
544 e820_add_region(end, ei_end - end, ei->type);
545 ei->size = start - ei->addr;
546 real_removed_size += size;
547 continue;
548 }
549
550 /* partially covered */
551 final_start = max(start, ei->addr);
552 final_end = min(end, ei_end);
553 if (final_start >= final_end)
554 continue;
555 real_removed_size += final_end - final_start;
556
557 /*
558 * left range could be head or tail, so need to update
559 * size at first.
560 */
561 ei->size -= final_end - final_start;
562 if (ei->addr < final_start)
563 continue;
564 ei->addr = final_end;
565 }
566 return real_removed_size;
567}
568
569void __init update_e820(void)
570{
571 if (sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map))
572 return;
573 printk(KERN_INFO "e820: modified physical RAM map:\n");
574 e820_print_map("modified");
575}
576static void __init update_e820_saved(void)
577{
578 sanitize_e820_map(e820_saved->map, ARRAY_SIZE(e820_saved->map),
579 &e820_saved->nr_map);
580}
581#define MAX_GAP_END 0x100000000ull
582/*
583 * Search for a gap in the e820 memory space from start_addr to end_addr.
584 */
585__init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
586 unsigned long start_addr, unsigned long long end_addr)
587{
588 unsigned long long last;
589 int i = e820->nr_map;
590 int found = 0;
591
592 last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
593
594 while (--i >= 0) {
595 unsigned long long start = e820->map[i].addr;
596 unsigned long long end = start + e820->map[i].size;
597
598 if (end < start_addr)
599 continue;
600
601 /*
602 * Since "last" is at most 4GB, we know we'll
603 * fit in 32 bits if this condition is true
604 */
605 if (last > end) {
606 unsigned long gap = last - end;
607
608 if (gap >= *gapsize) {
609 *gapsize = gap;
610 *gapstart = end;
611 found = 1;
612 }
613 }
614 if (start < last)
615 last = start;
616 }
617 return found;
618}
619
620/*
621 * Search for the biggest gap in the low 32 bits of the e820
622 * memory space. We pass this space to PCI to assign MMIO resources
623 * for hotplug or unconfigured devices in.
624 * Hopefully the BIOS let enough space left.
625 */
626__init void e820_setup_gap(void)
627{
628 unsigned long gapstart, gapsize;
629 int found;
630
631 gapstart = 0x10000000;
632 gapsize = 0x400000;
633 found = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
634
635#ifdef CONFIG_X86_64
636 if (!found) {
637 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
638 printk(KERN_ERR
639 "e820: cannot find a gap in the 32bit address range\n"
640 "e820: PCI devices with unassigned 32bit BARs may break!\n");
641 }
642#endif
643
644 /*
645 * e820_reserve_resources_late protect stolen RAM already
646 */
647 pci_mem_start = gapstart;
648
649 printk(KERN_INFO
650 "e820: [mem %#010lx-%#010lx] available for PCI devices\n",
651 gapstart, gapstart + gapsize - 1);
652}
653
654/*
655 * Called late during init, in free_initmem().
656 *
657 * Initial e820 and e820_saved are largish __initdata arrays.
658 * Copy them to (usually much smaller) dynamically allocated area.
659 * This is done after all tweaks we ever do to them:
660 * all functions which modify them are __init functions,
661 * they won't exist after this point.
662 */
663__init void e820_reallocate_tables(void)
664{
665 struct e820map *n;
666 int size;
667
668 size = offsetof(struct e820map, map) + sizeof(struct e820entry) * e820->nr_map;
669 n = kmalloc(size, GFP_KERNEL);
670 BUG_ON(!n);
671 memcpy(n, e820, size);
672 e820 = n;
673
674 size = offsetof(struct e820map, map) + sizeof(struct e820entry) * e820_saved->nr_map;
675 n = kmalloc(size, GFP_KERNEL);
676 BUG_ON(!n);
677 memcpy(n, e820_saved, size);
678 e820_saved = n;
679}
680
681/**
682 * Because of the size limitation of struct boot_params, only first
683 * 128 E820 memory entries are passed to kernel via
684 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
685 * linked list of struct setup_data, which is parsed here.
686 */
687void __init parse_e820_ext(u64 phys_addr, u32 data_len)
688{
689 int entries;
690 struct e820entry *extmap;
691 struct setup_data *sdata;
692
693 sdata = early_memremap(phys_addr, data_len);
694 entries = sdata->len / sizeof(struct e820entry);
695 extmap = (struct e820entry *)(sdata->data);
696 __append_e820_map(extmap, entries);
697 sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
698 early_memunmap(sdata, data_len);
699 printk(KERN_INFO "e820: extended physical RAM map:\n");
700 e820_print_map("extended");
701}
702
703#if defined(CONFIG_X86_64) || \
704 (defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
705/**
706 * Find the ranges of physical addresses that do not correspond to
707 * e820 RAM areas and mark the corresponding pages as nosave for
708 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
709 *
710 * This function requires the e820 map to be sorted and without any
711 * overlapping entries.
712 */
713void __init e820_mark_nosave_regions(unsigned long limit_pfn)
714{
715 int i;
716 unsigned long pfn = 0;
717
718 for (i = 0; i < e820->nr_map; i++) {
719 struct e820entry *ei = &e820->map[i];
720
721 if (pfn < PFN_UP(ei->addr))
722 register_nosave_region(pfn, PFN_UP(ei->addr));
723
724 pfn = PFN_DOWN(ei->addr + ei->size);
725
726 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
727 register_nosave_region(PFN_UP(ei->addr), pfn);
728
729 if (pfn >= limit_pfn)
730 break;
731 }
732}
733#endif
734
735#ifdef CONFIG_ACPI
736/**
737 * Mark ACPI NVS memory region, so that we can save/restore it during
738 * hibernation and the subsequent resume.
739 */
740static int __init e820_mark_nvs_memory(void)
741{
742 int i;
743
744 for (i = 0; i < e820->nr_map; i++) {
745 struct e820entry *ei = &e820->map[i];
746
747 if (ei->type == E820_NVS)
748 acpi_nvs_register(ei->addr, ei->size);
749 }
750
751 return 0;
752}
753core_initcall(e820_mark_nvs_memory);
754#endif
755
756/*
757 * pre allocated 4k and reserved it in memblock and e820_saved
758 */
759u64 __init early_reserve_e820(u64 size, u64 align)
760{
761 u64 addr;
762
763 addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
764 if (addr) {
765 e820_update_range_saved(addr, size, E820_RAM, E820_RESERVED);
766 printk(KERN_INFO "e820: update e820_saved for early_reserve_e820\n");
767 update_e820_saved();
768 }
769
770 return addr;
771}
772
773#ifdef CONFIG_X86_32
774# ifdef CONFIG_X86_PAE
775# define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
776# else
777# define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
778# endif
779#else /* CONFIG_X86_32 */
780# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
781#endif
782
783/*
784 * Find the highest page frame number we have available
785 */
786static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
787{
788 int i;
789 unsigned long last_pfn = 0;
790 unsigned long max_arch_pfn = MAX_ARCH_PFN;
791
792 for (i = 0; i < e820->nr_map; i++) {
793 struct e820entry *ei = &e820->map[i];
794 unsigned long start_pfn;
795 unsigned long end_pfn;
796
797 if (ei->type != type)
798 continue;
799
800 start_pfn = ei->addr >> PAGE_SHIFT;
801 end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
802
803 if (start_pfn >= limit_pfn)
804 continue;
805 if (end_pfn > limit_pfn) {
806 last_pfn = limit_pfn;
807 break;
808 }
809 if (end_pfn > last_pfn)
810 last_pfn = end_pfn;
811 }
812
813 if (last_pfn > max_arch_pfn)
814 last_pfn = max_arch_pfn;
815
816 printk(KERN_INFO "e820: last_pfn = %#lx max_arch_pfn = %#lx\n",
817 last_pfn, max_arch_pfn);
818 return last_pfn;
819}
820unsigned long __init e820_end_of_ram_pfn(void)
821{
822 return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
823}
824
825unsigned long __init e820_end_of_low_ram_pfn(void)
826{
827 return e820_end_pfn(1UL << (32 - PAGE_SHIFT), E820_RAM);
828}
829
830static void __init early_panic(char *msg)
831{
832 early_printk(msg);
833 panic(msg);
834}
835
836static int userdef __initdata;
837
838/* "mem=nopentium" disables the 4MB page tables. */
839static int __init parse_memopt(char *p)
840{
841 u64 mem_size;
842
843 if (!p)
844 return -EINVAL;
845
846 if (!strcmp(p, "nopentium")) {
847#ifdef CONFIG_X86_32
848 setup_clear_cpu_cap(X86_FEATURE_PSE);
849 return 0;
850#else
851 printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
852 return -EINVAL;
853#endif
854 }
855
856 userdef = 1;
857 mem_size = memparse(p, &p);
858 /* don't remove all of memory when handling "mem={invalid}" param */
859 if (mem_size == 0)
860 return -EINVAL;
861 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
862
863 return 0;
864}
865early_param("mem", parse_memopt);
866
867static int __init parse_memmap_one(char *p)
868{
869 char *oldp;
870 u64 start_at, mem_size;
871
872 if (!p)
873 return -EINVAL;
874
875 if (!strncmp(p, "exactmap", 8)) {
876#ifdef CONFIG_CRASH_DUMP
877 /*
878 * If we are doing a crash dump, we still need to know
879 * the real mem size before original memory map is
880 * reset.
881 */
882 saved_max_pfn = e820_end_of_ram_pfn();
883#endif
884 e820->nr_map = 0;
885 userdef = 1;
886 return 0;
887 }
888
889 oldp = p;
890 mem_size = memparse(p, &p);
891 if (p == oldp)
892 return -EINVAL;
893
894 userdef = 1;
895 if (*p == '@') {
896 start_at = memparse(p+1, &p);
897 e820_add_region(start_at, mem_size, E820_RAM);
898 } else if (*p == '#') {
899 start_at = memparse(p+1, &p);
900 e820_add_region(start_at, mem_size, E820_ACPI);
901 } else if (*p == '$') {
902 start_at = memparse(p+1, &p);
903 e820_add_region(start_at, mem_size, E820_RESERVED);
904 } else if (*p == '!') {
905 start_at = memparse(p+1, &p);
906 e820_add_region(start_at, mem_size, E820_PRAM);
907 } else
908 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
909
910 return *p == '\0' ? 0 : -EINVAL;
911}
912static int __init parse_memmap_opt(char *str)
913{
914 while (str) {
915 char *k = strchr(str, ',');
916
917 if (k)
918 *k++ = 0;
919
920 parse_memmap_one(str);
921 str = k;
922 }
923
924 return 0;
925}
926early_param("memmap", parse_memmap_opt);
927
928void __init finish_e820_parsing(void)
929{
930 if (userdef) {
931 if (sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map),
932 &e820->nr_map) < 0)
933 early_panic("Invalid user supplied memory map");
934
935 printk(KERN_INFO "e820: user-defined physical RAM map:\n");
936 e820_print_map("user");
937 }
938}
939
940static const char *__init e820_type_to_string(int e820_type)
941{
942 switch (e820_type) {
943 case E820_RESERVED_KERN:
944 case E820_RAM: return "System RAM";
945 case E820_ACPI: return "ACPI Tables";
946 case E820_NVS: return "ACPI Non-volatile Storage";
947 case E820_UNUSABLE: return "Unusable memory";
948 case E820_PRAM: return "Persistent Memory (legacy)";
949 case E820_PMEM: return "Persistent Memory";
950 default: return "reserved";
951 }
952}
953
954static unsigned long __init e820_type_to_iomem_type(int e820_type)
955{
956 switch (e820_type) {
957 case E820_RESERVED_KERN:
958 case E820_RAM:
959 return IORESOURCE_SYSTEM_RAM;
960 case E820_ACPI:
961 case E820_NVS:
962 case E820_UNUSABLE:
963 case E820_PRAM:
964 case E820_PMEM:
965 default:
966 return IORESOURCE_MEM;
967 }
968}
969
970static unsigned long __init e820_type_to_iores_desc(int e820_type)
971{
972 switch (e820_type) {
973 case E820_ACPI:
974 return IORES_DESC_ACPI_TABLES;
975 case E820_NVS:
976 return IORES_DESC_ACPI_NV_STORAGE;
977 case E820_PMEM:
978 return IORES_DESC_PERSISTENT_MEMORY;
979 case E820_PRAM:
980 return IORES_DESC_PERSISTENT_MEMORY_LEGACY;
981 case E820_RESERVED_KERN:
982 case E820_RAM:
983 case E820_UNUSABLE:
984 default:
985 return IORES_DESC_NONE;
986 }
987}
988
989static bool __init do_mark_busy(u32 type, struct resource *res)
990{
991 /* this is the legacy bios/dos rom-shadow + mmio region */
992 if (res->start < (1ULL<<20))
993 return true;
994
995 /*
996 * Treat persistent memory like device memory, i.e. reserve it
997 * for exclusive use of a driver
998 */
999 switch (type) {
1000 case E820_RESERVED:
1001 case E820_PRAM:
1002 case E820_PMEM:
1003 return false;
1004 default:
1005 return true;
1006 }
1007}
1008
1009/*
1010 * Mark e820 reserved areas as busy for the resource manager.
1011 */
1012static struct resource __initdata *e820_res;
1013void __init e820_reserve_resources(void)
1014{
1015 int i;
1016 struct resource *res;
1017 u64 end;
1018
1019 res = alloc_bootmem(sizeof(struct resource) * e820->nr_map);
1020 e820_res = res;
1021 for (i = 0; i < e820->nr_map; i++) {
1022 end = e820->map[i].addr + e820->map[i].size - 1;
1023 if (end != (resource_size_t)end) {
1024 res++;
1025 continue;
1026 }
1027 res->name = e820_type_to_string(e820->map[i].type);
1028 res->start = e820->map[i].addr;
1029 res->end = end;
1030
1031 res->flags = e820_type_to_iomem_type(e820->map[i].type);
1032 res->desc = e820_type_to_iores_desc(e820->map[i].type);
1033
1034 /*
1035 * don't register the region that could be conflicted with
1036 * pci device BAR resource and insert them later in
1037 * pcibios_resource_survey()
1038 */
1039 if (do_mark_busy(e820->map[i].type, res)) {
1040 res->flags |= IORESOURCE_BUSY;
1041 insert_resource(&iomem_resource, res);
1042 }
1043 res++;
1044 }
1045
1046 for (i = 0; i < e820_saved->nr_map; i++) {
1047 struct e820entry *entry = &e820_saved->map[i];
1048 firmware_map_add_early(entry->addr,
1049 entry->addr + entry->size,
1050 e820_type_to_string(entry->type));
1051 }
1052}
1053
1054/* How much should we pad RAM ending depending on where it is? */
1055static unsigned long __init ram_alignment(resource_size_t pos)
1056{
1057 unsigned long mb = pos >> 20;
1058
1059 /* To 64kB in the first megabyte */
1060 if (!mb)
1061 return 64*1024;
1062
1063 /* To 1MB in the first 16MB */
1064 if (mb < 16)
1065 return 1024*1024;
1066
1067 /* To 64MB for anything above that */
1068 return 64*1024*1024;
1069}
1070
1071#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
1072
1073void __init e820_reserve_resources_late(void)
1074{
1075 int i;
1076 struct resource *res;
1077
1078 res = e820_res;
1079 for (i = 0; i < e820->nr_map; i++) {
1080 if (!res->parent && res->end)
1081 insert_resource_expand_to_fit(&iomem_resource, res);
1082 res++;
1083 }
1084
1085 /*
1086 * Try to bump up RAM regions to reasonable boundaries to
1087 * avoid stolen RAM:
1088 */
1089 for (i = 0; i < e820->nr_map; i++) {
1090 struct e820entry *entry = &e820->map[i];
1091 u64 start, end;
1092
1093 if (entry->type != E820_RAM)
1094 continue;
1095 start = entry->addr + entry->size;
1096 end = round_up(start, ram_alignment(start)) - 1;
1097 if (end > MAX_RESOURCE_SIZE)
1098 end = MAX_RESOURCE_SIZE;
1099 if (start >= end)
1100 continue;
1101 printk(KERN_DEBUG
1102 "e820: reserve RAM buffer [mem %#010llx-%#010llx]\n",
1103 start, end);
1104 reserve_region_with_split(&iomem_resource, start, end,
1105 "RAM buffer");
1106 }
1107}
1108
1109char *__init default_machine_specific_memory_setup(void)
1110{
1111 char *who = "BIOS-e820";
1112 u32 new_nr;
1113 /*
1114 * Try to copy the BIOS-supplied E820-map.
1115 *
1116 * Otherwise fake a memory map; one section from 0k->640k,
1117 * the next section from 1mb->appropriate_mem_k
1118 */
1119 new_nr = boot_params.e820_entries;
1120 sanitize_e820_map(boot_params.e820_map,
1121 ARRAY_SIZE(boot_params.e820_map),
1122 &new_nr);
1123 boot_params.e820_entries = new_nr;
1124 if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1125 < 0) {
1126 u64 mem_size;
1127
1128 /* compare results from other methods and take the greater */
1129 if (boot_params.alt_mem_k
1130 < boot_params.screen_info.ext_mem_k) {
1131 mem_size = boot_params.screen_info.ext_mem_k;
1132 who = "BIOS-88";
1133 } else {
1134 mem_size = boot_params.alt_mem_k;
1135 who = "BIOS-e801";
1136 }
1137
1138 e820->nr_map = 0;
1139 e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1140 e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1141 }
1142
1143 /* In case someone cares... */
1144 return who;
1145}
1146
1147void __init setup_memory_map(void)
1148{
1149 char *who;
1150
1151 who = x86_init.resources.memory_setup();
1152 memcpy(e820_saved, e820, sizeof(struct e820map));
1153 printk(KERN_INFO "e820: BIOS-provided physical RAM map:\n");
1154 e820_print_map(who);
1155}
1156
1157void __init memblock_x86_fill(void)
1158{
1159 int i;
1160 u64 end;
1161
1162 /*
1163 * EFI may have more than 128 entries
1164 * We are safe to enable resizing, beause memblock_x86_fill()
1165 * is rather later for x86
1166 */
1167 memblock_allow_resize();
1168
1169 for (i = 0; i < e820->nr_map; i++) {
1170 struct e820entry *ei = &e820->map[i];
1171
1172 end = ei->addr + ei->size;
1173 if (end != (resource_size_t)end)
1174 continue;
1175
1176 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
1177 continue;
1178
1179 memblock_add(ei->addr, ei->size);
1180 }
1181
1182 /* throw away partial pages */
1183 memblock_trim_memory(PAGE_SIZE);
1184
1185 memblock_dump_all();
1186}
1187
1188void __init memblock_find_dma_reserve(void)
1189{
1190#ifdef CONFIG_X86_64
1191 u64 nr_pages = 0, nr_free_pages = 0;
1192 unsigned long start_pfn, end_pfn;
1193 phys_addr_t start, end;
1194 int i;
1195 u64 u;
1196
1197 /*
1198 * need to find out used area below MAX_DMA_PFN
1199 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1200 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1201 */
1202 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
1203 start_pfn = min(start_pfn, MAX_DMA_PFN);
1204 end_pfn = min(end_pfn, MAX_DMA_PFN);
1205 nr_pages += end_pfn - start_pfn;
1206 }
1207
1208 for_each_free_mem_range(u, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end,
1209 NULL) {
1210 start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN);
1211 end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN);
1212 if (start_pfn < end_pfn)
1213 nr_free_pages += end_pfn - start_pfn;
1214 }
1215
1216 set_dma_reserve(nr_pages - nr_free_pages);
1217#endif
1218}