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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
28/*
29 * The e820 map is the map that gets modified e.g. with command line parameters
30 * and that is also registered with modifications in the kernel resource tree
31 * with the iomem_resource as parent.
32 *
33 * The e820_saved is directly saved after the BIOS-provided memory map is
34 * copied. It doesn't get modified afterwards. It's registered for the
35 * /sys/firmware/memmap interface.
36 *
37 * That memory map is not modified and is used as base for kexec. The kexec'd
38 * kernel should get the same memory map as the firmware provides. Then the
39 * user can e.g. boot the original kernel with mem=1G while still booting the
40 * next kernel with full memory.
41 */
42struct e820map e820;
43struct e820map e820_saved;
44
45/* For PCI or other memory-mapped resources */
46unsigned long pci_mem_start = 0xaeedbabe;
47#ifdef CONFIG_PCI
48EXPORT_SYMBOL(pci_mem_start);
49#endif
50
51/*
52 * This function checks if any part of the range <start,end> is mapped
53 * with type.
54 */
55int
56e820_any_mapped(u64 start, u64 end, unsigned type)
57{
58 int i;
59
60 for (i = 0; i < e820.nr_map; i++) {
61 struct e820entry *ei = &e820.map[i];
62
63 if (type && ei->type != type)
64 continue;
65 if (ei->addr >= end || ei->addr + ei->size <= start)
66 continue;
67 return 1;
68 }
69 return 0;
70}
71EXPORT_SYMBOL_GPL(e820_any_mapped);
72
73/*
74 * This function checks if the entire range <start,end> is mapped with type.
75 *
76 * Note: this function only works correct if the e820 table is sorted and
77 * not-overlapping, which is the case
78 */
79int __init e820_all_mapped(u64 start, u64 end, unsigned type)
80{
81 int i;
82
83 for (i = 0; i < e820.nr_map; i++) {
84 struct e820entry *ei = &e820.map[i];
85
86 if (type && ei->type != type)
87 continue;
88 /* is the region (part) in overlap with the current region ?*/
89 if (ei->addr >= end || ei->addr + ei->size <= start)
90 continue;
91
92 /* if the region is at the beginning of <start,end> we move
93 * start to the end of the region since it's ok until there
94 */
95 if (ei->addr <= start)
96 start = ei->addr + ei->size;
97 /*
98 * if start is now at or beyond end, we're done, full
99 * coverage
100 */
101 if (start >= end)
102 return 1;
103 }
104 return 0;
105}
106
107/*
108 * Add a memory region to the kernel e820 map.
109 */
110static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
111 int type)
112{
113 int x = e820x->nr_map;
114
115 if (x >= ARRAY_SIZE(e820x->map)) {
116 printk(KERN_ERR "e820: too many entries; ignoring [mem %#010llx-%#010llx]\n",
117 (unsigned long long) start,
118 (unsigned long long) (start + size - 1));
119 return;
120 }
121
122 e820x->map[x].addr = start;
123 e820x->map[x].size = size;
124 e820x->map[x].type = type;
125 e820x->nr_map++;
126}
127
128void __init e820_add_region(u64 start, u64 size, int type)
129{
130 __e820_add_region(&e820, start, size, type);
131}
132
133static void __init e820_print_type(u32 type)
134{
135 switch (type) {
136 case E820_RAM:
137 case E820_RESERVED_KERN:
138 printk(KERN_CONT "usable");
139 break;
140 case E820_RESERVED:
141 printk(KERN_CONT "reserved");
142 break;
143 case E820_ACPI:
144 printk(KERN_CONT "ACPI data");
145 break;
146 case E820_NVS:
147 printk(KERN_CONT "ACPI NVS");
148 break;
149 case E820_UNUSABLE:
150 printk(KERN_CONT "unusable");
151 break;
152 default:
153 printk(KERN_CONT "type %u", type);
154 break;
155 }
156}
157
158void __init e820_print_map(char *who)
159{
160 int i;
161
162 for (i = 0; i < e820.nr_map; i++) {
163 printk(KERN_INFO "%s: [mem %#018Lx-%#018Lx] ", who,
164 (unsigned long long) e820.map[i].addr,
165 (unsigned long long)
166 (e820.map[i].addr + e820.map[i].size - 1));
167 e820_print_type(e820.map[i].type);
168 printk(KERN_CONT "\n");
169 }
170}
171
172/*
173 * Sanitize the BIOS e820 map.
174 *
175 * Some e820 responses include overlapping entries. The following
176 * replaces the original e820 map with a new one, removing overlaps,
177 * and resolving conflicting memory types in favor of highest
178 * numbered type.
179 *
180 * The input parameter biosmap points to an array of 'struct
181 * e820entry' which on entry has elements in the range [0, *pnr_map)
182 * valid, and which has space for up to max_nr_map entries.
183 * On return, the resulting sanitized e820 map entries will be in
184 * overwritten in the same location, starting at biosmap.
185 *
186 * The integer pointed to by pnr_map must be valid on entry (the
187 * current number of valid entries located at biosmap) and will
188 * be updated on return, with the new number of valid entries
189 * (something no more than max_nr_map.)
190 *
191 * The return value from sanitize_e820_map() is zero if it
192 * successfully 'sanitized' the map entries passed in, and is -1
193 * if it did nothing, which can happen if either of (1) it was
194 * only passed one map entry, or (2) any of the input map entries
195 * were invalid (start + size < start, meaning that the size was
196 * so big the described memory range wrapped around through zero.)
197 *
198 * Visually we're performing the following
199 * (1,2,3,4 = memory types)...
200 *
201 * Sample memory map (w/overlaps):
202 * ____22__________________
203 * ______________________4_
204 * ____1111________________
205 * _44_____________________
206 * 11111111________________
207 * ____________________33__
208 * ___________44___________
209 * __________33333_________
210 * ______________22________
211 * ___________________2222_
212 * _________111111111______
213 * _____________________11_
214 * _________________4______
215 *
216 * Sanitized equivalent (no overlap):
217 * 1_______________________
218 * _44_____________________
219 * ___1____________________
220 * ____22__________________
221 * ______11________________
222 * _________1______________
223 * __________3_____________
224 * ___________44___________
225 * _____________33_________
226 * _______________2________
227 * ________________1_______
228 * _________________4______
229 * ___________________2____
230 * ____________________33__
231 * ______________________4_
232 */
233struct change_member {
234 struct e820entry *pbios; /* pointer to original bios entry */
235 unsigned long long addr; /* address for this change point */
236};
237
238static int __init cpcompare(const void *a, const void *b)
239{
240 struct change_member * const *app = a, * const *bpp = b;
241 const struct change_member *ap = *app, *bp = *bpp;
242
243 /*
244 * Inputs are pointers to two elements of change_point[]. If their
245 * addresses are unequal, their difference dominates. If the addresses
246 * are equal, then consider one that represents the end of its region
247 * to be greater than one that does not.
248 */
249 if (ap->addr != bp->addr)
250 return ap->addr > bp->addr ? 1 : -1;
251
252 return (ap->addr != ap->pbios->addr) - (bp->addr != bp->pbios->addr);
253}
254
255int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
256 u32 *pnr_map)
257{
258 static struct change_member change_point_list[2*E820_X_MAX] __initdata;
259 static struct change_member *change_point[2*E820_X_MAX] __initdata;
260 static struct e820entry *overlap_list[E820_X_MAX] __initdata;
261 static struct e820entry new_bios[E820_X_MAX] __initdata;
262 unsigned long current_type, last_type;
263 unsigned long long last_addr;
264 int chgidx;
265 int overlap_entries;
266 int new_bios_entry;
267 int old_nr, new_nr, chg_nr;
268 int i;
269
270 /* if there's only one memory region, don't bother */
271 if (*pnr_map < 2)
272 return -1;
273
274 old_nr = *pnr_map;
275 BUG_ON(old_nr > max_nr_map);
276
277 /* bail out if we find any unreasonable addresses in bios map */
278 for (i = 0; i < old_nr; i++)
279 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
280 return -1;
281
282 /* create pointers for initial change-point information (for sorting) */
283 for (i = 0; i < 2 * old_nr; i++)
284 change_point[i] = &change_point_list[i];
285
286 /* record all known change-points (starting and ending addresses),
287 omitting those that are for empty memory regions */
288 chgidx = 0;
289 for (i = 0; i < old_nr; i++) {
290 if (biosmap[i].size != 0) {
291 change_point[chgidx]->addr = biosmap[i].addr;
292 change_point[chgidx++]->pbios = &biosmap[i];
293 change_point[chgidx]->addr = biosmap[i].addr +
294 biosmap[i].size;
295 change_point[chgidx++]->pbios = &biosmap[i];
296 }
297 }
298 chg_nr = chgidx;
299
300 /* sort change-point list by memory addresses (low -> high) */
301 sort(change_point, chg_nr, sizeof *change_point, cpcompare, NULL);
302
303 /* create a new bios memory map, removing overlaps */
304 overlap_entries = 0; /* number of entries in the overlap table */
305 new_bios_entry = 0; /* index for creating new bios map entries */
306 last_type = 0; /* start with undefined memory type */
307 last_addr = 0; /* start with 0 as last starting address */
308
309 /* loop through change-points, determining affect on the new bios map */
310 for (chgidx = 0; chgidx < chg_nr; chgidx++) {
311 /* keep track of all overlapping bios entries */
312 if (change_point[chgidx]->addr ==
313 change_point[chgidx]->pbios->addr) {
314 /*
315 * add map entry to overlap list (> 1 entry
316 * implies an overlap)
317 */
318 overlap_list[overlap_entries++] =
319 change_point[chgidx]->pbios;
320 } else {
321 /*
322 * remove entry from list (order independent,
323 * so swap with last)
324 */
325 for (i = 0; i < overlap_entries; i++) {
326 if (overlap_list[i] ==
327 change_point[chgidx]->pbios)
328 overlap_list[i] =
329 overlap_list[overlap_entries-1];
330 }
331 overlap_entries--;
332 }
333 /*
334 * if there are overlapping entries, decide which
335 * "type" to use (larger value takes precedence --
336 * 1=usable, 2,3,4,4+=unusable)
337 */
338 current_type = 0;
339 for (i = 0; i < overlap_entries; i++)
340 if (overlap_list[i]->type > current_type)
341 current_type = overlap_list[i]->type;
342 /*
343 * continue building up new bios map based on this
344 * information
345 */
346 if (current_type != last_type) {
347 if (last_type != 0) {
348 new_bios[new_bios_entry].size =
349 change_point[chgidx]->addr - last_addr;
350 /*
351 * move forward only if the new size
352 * was non-zero
353 */
354 if (new_bios[new_bios_entry].size != 0)
355 /*
356 * no more space left for new
357 * bios entries ?
358 */
359 if (++new_bios_entry >= max_nr_map)
360 break;
361 }
362 if (current_type != 0) {
363 new_bios[new_bios_entry].addr =
364 change_point[chgidx]->addr;
365 new_bios[new_bios_entry].type = current_type;
366 last_addr = change_point[chgidx]->addr;
367 }
368 last_type = current_type;
369 }
370 }
371 /* retain count for new bios entries */
372 new_nr = new_bios_entry;
373
374 /* copy new bios mapping into original location */
375 memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
376 *pnr_map = new_nr;
377
378 return 0;
379}
380
381static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
382{
383 while (nr_map) {
384 u64 start = biosmap->addr;
385 u64 size = biosmap->size;
386 u64 end = start + size;
387 u32 type = biosmap->type;
388
389 /* Overflow in 64 bits? Ignore the memory map. */
390 if (start > end)
391 return -1;
392
393 e820_add_region(start, size, type);
394
395 biosmap++;
396 nr_map--;
397 }
398 return 0;
399}
400
401/*
402 * Copy the BIOS e820 map into a safe place.
403 *
404 * Sanity-check it while we're at it..
405 *
406 * If we're lucky and live on a modern system, the setup code
407 * will have given us a memory map that we can use to properly
408 * set up memory. If we aren't, we'll fake a memory map.
409 */
410static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
411{
412 /* Only one memory region (or negative)? Ignore it */
413 if (nr_map < 2)
414 return -1;
415
416 return __append_e820_map(biosmap, nr_map);
417}
418
419static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
420 u64 size, unsigned old_type,
421 unsigned new_type)
422{
423 u64 end;
424 unsigned int i;
425 u64 real_updated_size = 0;
426
427 BUG_ON(old_type == new_type);
428
429 if (size > (ULLONG_MAX - start))
430 size = ULLONG_MAX - start;
431
432 end = start + size;
433 printk(KERN_DEBUG "e820: update [mem %#010Lx-%#010Lx] ",
434 (unsigned long long) start, (unsigned long long) (end - 1));
435 e820_print_type(old_type);
436 printk(KERN_CONT " ==> ");
437 e820_print_type(new_type);
438 printk(KERN_CONT "\n");
439
440 for (i = 0; i < e820x->nr_map; i++) {
441 struct e820entry *ei = &e820x->map[i];
442 u64 final_start, final_end;
443 u64 ei_end;
444
445 if (ei->type != old_type)
446 continue;
447
448 ei_end = ei->addr + ei->size;
449 /* totally covered by new range? */
450 if (ei->addr >= start && ei_end <= end) {
451 ei->type = new_type;
452 real_updated_size += ei->size;
453 continue;
454 }
455
456 /* new range is totally covered? */
457 if (ei->addr < start && ei_end > end) {
458 __e820_add_region(e820x, start, size, new_type);
459 __e820_add_region(e820x, end, ei_end - end, ei->type);
460 ei->size = start - ei->addr;
461 real_updated_size += size;
462 continue;
463 }
464
465 /* partially covered */
466 final_start = max(start, ei->addr);
467 final_end = min(end, ei_end);
468 if (final_start >= final_end)
469 continue;
470
471 __e820_add_region(e820x, final_start, final_end - final_start,
472 new_type);
473
474 real_updated_size += final_end - final_start;
475
476 /*
477 * left range could be head or tail, so need to update
478 * size at first.
479 */
480 ei->size -= final_end - final_start;
481 if (ei->addr < final_start)
482 continue;
483 ei->addr = final_end;
484 }
485 return real_updated_size;
486}
487
488u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
489 unsigned new_type)
490{
491 return __e820_update_range(&e820, start, size, old_type, new_type);
492}
493
494static u64 __init e820_update_range_saved(u64 start, u64 size,
495 unsigned old_type, unsigned new_type)
496{
497 return __e820_update_range(&e820_saved, start, size, old_type,
498 new_type);
499}
500
501/* make e820 not cover the range */
502u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
503 int checktype)
504{
505 int i;
506 u64 end;
507 u64 real_removed_size = 0;
508
509 if (size > (ULLONG_MAX - start))
510 size = ULLONG_MAX - start;
511
512 end = start + size;
513 printk(KERN_DEBUG "e820: remove [mem %#010Lx-%#010Lx] ",
514 (unsigned long long) start, (unsigned long long) (end - 1));
515 if (checktype)
516 e820_print_type(old_type);
517 printk(KERN_CONT "\n");
518
519 for (i = 0; i < e820.nr_map; i++) {
520 struct e820entry *ei = &e820.map[i];
521 u64 final_start, final_end;
522 u64 ei_end;
523
524 if (checktype && ei->type != old_type)
525 continue;
526
527 ei_end = ei->addr + ei->size;
528 /* totally covered? */
529 if (ei->addr >= start && ei_end <= end) {
530 real_removed_size += ei->size;
531 memset(ei, 0, sizeof(struct e820entry));
532 continue;
533 }
534
535 /* new range is totally covered? */
536 if (ei->addr < start && ei_end > end) {
537 e820_add_region(end, ei_end - end, ei->type);
538 ei->size = start - ei->addr;
539 real_removed_size += size;
540 continue;
541 }
542
543 /* partially covered */
544 final_start = max(start, ei->addr);
545 final_end = min(end, ei_end);
546 if (final_start >= final_end)
547 continue;
548 real_removed_size += final_end - final_start;
549
550 /*
551 * left range could be head or tail, so need to update
552 * size at first.
553 */
554 ei->size -= final_end - final_start;
555 if (ei->addr < final_start)
556 continue;
557 ei->addr = final_end;
558 }
559 return real_removed_size;
560}
561
562void __init update_e820(void)
563{
564 u32 nr_map;
565
566 nr_map = e820.nr_map;
567 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr_map))
568 return;
569 e820.nr_map = nr_map;
570 printk(KERN_INFO "e820: modified physical RAM map:\n");
571 e820_print_map("modified");
572}
573static void __init update_e820_saved(void)
574{
575 u32 nr_map;
576
577 nr_map = e820_saved.nr_map;
578 if (sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map), &nr_map))
579 return;
580 e820_saved.nr_map = nr_map;
581}
582#define MAX_GAP_END 0x100000000ull
583/*
584 * Search for a gap in the e820 memory space from start_addr to end_addr.
585 */
586__init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
587 unsigned long start_addr, unsigned long long end_addr)
588{
589 unsigned long long last;
590 int i = e820.nr_map;
591 int found = 0;
592
593 last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
594
595 while (--i >= 0) {
596 unsigned long long start = e820.map[i].addr;
597 unsigned long long end = start + e820.map[i].size;
598
599 if (end < start_addr)
600 continue;
601
602 /*
603 * Since "last" is at most 4GB, we know we'll
604 * fit in 32 bits if this condition is true
605 */
606 if (last > end) {
607 unsigned long gap = last - end;
608
609 if (gap >= *gapsize) {
610 *gapsize = gap;
611 *gapstart = end;
612 found = 1;
613 }
614 }
615 if (start < last)
616 last = start;
617 }
618 return found;
619}
620
621/*
622 * Search for the biggest gap in the low 32 bits of the e820
623 * memory space. We pass this space to PCI to assign MMIO resources
624 * for hotplug or unconfigured devices in.
625 * Hopefully the BIOS let enough space left.
626 */
627__init void e820_setup_gap(void)
628{
629 unsigned long gapstart, gapsize;
630 int found;
631
632 gapstart = 0x10000000;
633 gapsize = 0x400000;
634 found = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
635
636#ifdef CONFIG_X86_64
637 if (!found) {
638 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
639 printk(KERN_ERR
640 "e820: cannot find a gap in the 32bit address range\n"
641 "e820: PCI devices with unassigned 32bit BARs may break!\n");
642 }
643#endif
644
645 /*
646 * e820_reserve_resources_late protect stolen RAM already
647 */
648 pci_mem_start = gapstart;
649
650 printk(KERN_INFO
651 "e820: [mem %#010lx-%#010lx] available for PCI devices\n",
652 gapstart, gapstart + gapsize - 1);
653}
654
655/**
656 * Because of the size limitation of struct boot_params, only first
657 * 128 E820 memory entries are passed to kernel via
658 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
659 * linked list of struct setup_data, which is parsed here.
660 */
661void __init parse_e820_ext(struct setup_data *sdata)
662{
663 int entries;
664 struct e820entry *extmap;
665
666 entries = sdata->len / sizeof(struct e820entry);
667 extmap = (struct e820entry *)(sdata->data);
668 __append_e820_map(extmap, entries);
669 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
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 and assumes the first e820 area to be RAM.
683 */
684void __init e820_mark_nosave_regions(unsigned long limit_pfn)
685{
686 int i;
687 unsigned long pfn;
688
689 pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
690 for (i = 1; i < e820.nr_map; i++) {
691 struct e820entry *ei = &e820.map[i];
692
693 if (pfn < PFN_UP(ei->addr))
694 register_nosave_region(pfn, PFN_UP(ei->addr));
695
696 pfn = PFN_DOWN(ei->addr + ei->size);
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, unsigned type)
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 if (ei->type != type)
769 continue;
770
771 start_pfn = ei->addr >> PAGE_SHIFT;
772 end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
773
774 if (start_pfn >= limit_pfn)
775 continue;
776 if (end_pfn > limit_pfn) {
777 last_pfn = limit_pfn;
778 break;
779 }
780 if (end_pfn > last_pfn)
781 last_pfn = end_pfn;
782 }
783
784 if (last_pfn > max_arch_pfn)
785 last_pfn = max_arch_pfn;
786
787 printk(KERN_INFO "e820: last_pfn = %#lx max_arch_pfn = %#lx\n",
788 last_pfn, max_arch_pfn);
789 return last_pfn;
790}
791unsigned long __init e820_end_of_ram_pfn(void)
792{
793 return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
794}
795
796unsigned long __init e820_end_of_low_ram_pfn(void)
797{
798 return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
799}
800
801static void early_panic(char *msg)
802{
803 early_printk(msg);
804 panic(msg);
805}
806
807static int userdef __initdata;
808
809/* "mem=nopentium" disables the 4MB page tables. */
810static int __init parse_memopt(char *p)
811{
812 u64 mem_size;
813
814 if (!p)
815 return -EINVAL;
816
817 if (!strcmp(p, "nopentium")) {
818#ifdef CONFIG_X86_32
819 setup_clear_cpu_cap(X86_FEATURE_PSE);
820 return 0;
821#else
822 printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
823 return -EINVAL;
824#endif
825 }
826
827 userdef = 1;
828 mem_size = memparse(p, &p);
829 /* don't remove all of memory when handling "mem={invalid}" param */
830 if (mem_size == 0)
831 return -EINVAL;
832 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
833
834 return 0;
835}
836early_param("mem", parse_memopt);
837
838static int __init parse_memmap_opt(char *p)
839{
840 char *oldp;
841 u64 start_at, mem_size;
842
843 if (!p)
844 return -EINVAL;
845
846 if (!strncmp(p, "exactmap", 8)) {
847#ifdef CONFIG_CRASH_DUMP
848 /*
849 * If we are doing a crash dump, we still need to know
850 * the real mem size before original memory map is
851 * reset.
852 */
853 saved_max_pfn = e820_end_of_ram_pfn();
854#endif
855 e820.nr_map = 0;
856 userdef = 1;
857 return 0;
858 }
859
860 oldp = p;
861 mem_size = memparse(p, &p);
862 if (p == oldp)
863 return -EINVAL;
864
865 userdef = 1;
866 if (*p == '@') {
867 start_at = memparse(p+1, &p);
868 e820_add_region(start_at, mem_size, E820_RAM);
869 } else if (*p == '#') {
870 start_at = memparse(p+1, &p);
871 e820_add_region(start_at, mem_size, E820_ACPI);
872 } else if (*p == '$') {
873 start_at = memparse(p+1, &p);
874 e820_add_region(start_at, mem_size, E820_RESERVED);
875 } else
876 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
877
878 return *p == '\0' ? 0 : -EINVAL;
879}
880early_param("memmap", parse_memmap_opt);
881
882void __init finish_e820_parsing(void)
883{
884 if (userdef) {
885 u32 nr = e820.nr_map;
886
887 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
888 early_panic("Invalid user supplied memory map");
889 e820.nr_map = nr;
890
891 printk(KERN_INFO "e820: user-defined physical RAM map:\n");
892 e820_print_map("user");
893 }
894}
895
896static inline const char *e820_type_to_string(int e820_type)
897{
898 switch (e820_type) {
899 case E820_RESERVED_KERN:
900 case E820_RAM: return "System RAM";
901 case E820_ACPI: return "ACPI Tables";
902 case E820_NVS: return "ACPI Non-volatile Storage";
903 case E820_UNUSABLE: return "Unusable memory";
904 default: return "reserved";
905 }
906}
907
908/*
909 * Mark e820 reserved areas as busy for the resource manager.
910 */
911static struct resource __initdata *e820_res;
912void __init e820_reserve_resources(void)
913{
914 int i;
915 struct resource *res;
916 u64 end;
917
918 res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
919 e820_res = res;
920 for (i = 0; i < e820.nr_map; i++) {
921 end = e820.map[i].addr + e820.map[i].size - 1;
922 if (end != (resource_size_t)end) {
923 res++;
924 continue;
925 }
926 res->name = e820_type_to_string(e820.map[i].type);
927 res->start = e820.map[i].addr;
928 res->end = end;
929
930 res->flags = IORESOURCE_MEM;
931
932 /*
933 * don't register the region that could be conflicted with
934 * pci device BAR resource and insert them later in
935 * pcibios_resource_survey()
936 */
937 if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
938 res->flags |= IORESOURCE_BUSY;
939 insert_resource(&iomem_resource, res);
940 }
941 res++;
942 }
943
944 for (i = 0; i < e820_saved.nr_map; i++) {
945 struct e820entry *entry = &e820_saved.map[i];
946 firmware_map_add_early(entry->addr,
947 entry->addr + entry->size - 1,
948 e820_type_to_string(entry->type));
949 }
950}
951
952/* How much should we pad RAM ending depending on where it is? */
953static unsigned long ram_alignment(resource_size_t pos)
954{
955 unsigned long mb = pos >> 20;
956
957 /* To 64kB in the first megabyte */
958 if (!mb)
959 return 64*1024;
960
961 /* To 1MB in the first 16MB */
962 if (mb < 16)
963 return 1024*1024;
964
965 /* To 64MB for anything above that */
966 return 64*1024*1024;
967}
968
969#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
970
971void __init e820_reserve_resources_late(void)
972{
973 int i;
974 struct resource *res;
975
976 res = e820_res;
977 for (i = 0; i < e820.nr_map; i++) {
978 if (!res->parent && res->end)
979 insert_resource_expand_to_fit(&iomem_resource, res);
980 res++;
981 }
982
983 /*
984 * Try to bump up RAM regions to reasonable boundaries to
985 * avoid stolen RAM:
986 */
987 for (i = 0; i < e820.nr_map; i++) {
988 struct e820entry *entry = &e820.map[i];
989 u64 start, end;
990
991 if (entry->type != E820_RAM)
992 continue;
993 start = entry->addr + entry->size;
994 end = round_up(start, ram_alignment(start)) - 1;
995 if (end > MAX_RESOURCE_SIZE)
996 end = MAX_RESOURCE_SIZE;
997 if (start >= end)
998 continue;
999 printk(KERN_DEBUG
1000 "e820: reserve RAM buffer [mem %#010llx-%#010llx]\n",
1001 start, end);
1002 reserve_region_with_split(&iomem_resource, start, end,
1003 "RAM buffer");
1004 }
1005}
1006
1007char *__init default_machine_specific_memory_setup(void)
1008{
1009 char *who = "BIOS-e820";
1010 u32 new_nr;
1011 /*
1012 * Try to copy the BIOS-supplied E820-map.
1013 *
1014 * Otherwise fake a memory map; one section from 0k->640k,
1015 * the next section from 1mb->appropriate_mem_k
1016 */
1017 new_nr = boot_params.e820_entries;
1018 sanitize_e820_map(boot_params.e820_map,
1019 ARRAY_SIZE(boot_params.e820_map),
1020 &new_nr);
1021 boot_params.e820_entries = new_nr;
1022 if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1023 < 0) {
1024 u64 mem_size;
1025
1026 /* compare results from other methods and take the greater */
1027 if (boot_params.alt_mem_k
1028 < boot_params.screen_info.ext_mem_k) {
1029 mem_size = boot_params.screen_info.ext_mem_k;
1030 who = "BIOS-88";
1031 } else {
1032 mem_size = boot_params.alt_mem_k;
1033 who = "BIOS-e801";
1034 }
1035
1036 e820.nr_map = 0;
1037 e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1038 e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1039 }
1040
1041 /* In case someone cares... */
1042 return who;
1043}
1044
1045void __init setup_memory_map(void)
1046{
1047 char *who;
1048
1049 who = x86_init.resources.memory_setup();
1050 memcpy(&e820_saved, &e820, sizeof(struct e820map));
1051 printk(KERN_INFO "e820: BIOS-provided physical RAM map:\n");
1052 e820_print_map(who);
1053}
1054
1055void __init memblock_x86_fill(void)
1056{
1057 int i;
1058 u64 end;
1059
1060 /*
1061 * EFI may have more than 128 entries
1062 * We are safe to enable resizing, beause memblock_x86_fill()
1063 * is rather later for x86
1064 */
1065 memblock_allow_resize();
1066
1067 for (i = 0; i < e820.nr_map; i++) {
1068 struct e820entry *ei = &e820.map[i];
1069
1070 end = ei->addr + ei->size;
1071 if (end != (resource_size_t)end)
1072 continue;
1073
1074 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
1075 continue;
1076
1077 memblock_add(ei->addr, ei->size);
1078 }
1079
1080 memblock_dump_all();
1081}
1082
1083void __init memblock_find_dma_reserve(void)
1084{
1085#ifdef CONFIG_X86_64
1086 u64 nr_pages = 0, nr_free_pages = 0;
1087 unsigned long start_pfn, end_pfn;
1088 phys_addr_t start, end;
1089 int i;
1090 u64 u;
1091
1092 /*
1093 * need to find out used area below MAX_DMA_PFN
1094 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1095 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1096 */
1097 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
1098 start_pfn = min_t(unsigned long, start_pfn, MAX_DMA_PFN);
1099 end_pfn = min_t(unsigned long, end_pfn, MAX_DMA_PFN);
1100 nr_pages += end_pfn - start_pfn;
1101 }
1102
1103 for_each_free_mem_range(u, MAX_NUMNODES, &start, &end, NULL) {
1104 start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN);
1105 end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN);
1106 if (start_pfn < end_pfn)
1107 nr_free_pages += end_pfn - start_pfn;
1108 }
1109
1110 set_dma_reserve(nr_pages - nr_free_pages);
1111#endif
1112}