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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(u64 phys_addr, u32 data_len)
662{
663 int entries;
664 struct e820entry *extmap;
665 struct setup_data *sdata;
666
667 sdata = early_memremap(phys_addr, data_len);
668 entries = sdata->len / sizeof(struct e820entry);
669 extmap = (struct e820entry *)(sdata->data);
670 __append_e820_map(extmap, entries);
671 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
672 early_iounmap(sdata, data_len);
673 printk(KERN_INFO "e820: extended physical RAM map:\n");
674 e820_print_map("extended");
675}
676
677#if defined(CONFIG_X86_64) || \
678 (defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
679/**
680 * Find the ranges of physical addresses that do not correspond to
681 * e820 RAM areas and mark the corresponding pages as nosave for
682 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
683 *
684 * This function requires the e820 map to be sorted and without any
685 * overlapping entries and assumes the first e820 area to be RAM.
686 */
687void __init e820_mark_nosave_regions(unsigned long limit_pfn)
688{
689 int i;
690 unsigned long pfn;
691
692 pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
693 for (i = 1; i < e820.nr_map; i++) {
694 struct e820entry *ei = &e820.map[i];
695
696 if (pfn < PFN_UP(ei->addr))
697 register_nosave_region(pfn, PFN_UP(ei->addr));
698
699 pfn = PFN_DOWN(ei->addr + ei->size);
700 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
701 register_nosave_region(PFN_UP(ei->addr), pfn);
702
703 if (pfn >= limit_pfn)
704 break;
705 }
706}
707#endif
708
709#ifdef CONFIG_ACPI
710/**
711 * Mark ACPI NVS memory region, so that we can save/restore it during
712 * hibernation and the subsequent resume.
713 */
714static int __init e820_mark_nvs_memory(void)
715{
716 int i;
717
718 for (i = 0; i < e820.nr_map; i++) {
719 struct e820entry *ei = &e820.map[i];
720
721 if (ei->type == E820_NVS)
722 acpi_nvs_register(ei->addr, ei->size);
723 }
724
725 return 0;
726}
727core_initcall(e820_mark_nvs_memory);
728#endif
729
730/*
731 * pre allocated 4k and reserved it in memblock and e820_saved
732 */
733u64 __init early_reserve_e820(u64 size, u64 align)
734{
735 u64 addr;
736
737 addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
738 if (addr) {
739 e820_update_range_saved(addr, size, E820_RAM, E820_RESERVED);
740 printk(KERN_INFO "e820: update e820_saved for early_reserve_e820\n");
741 update_e820_saved();
742 }
743
744 return addr;
745}
746
747#ifdef CONFIG_X86_32
748# ifdef CONFIG_X86_PAE
749# define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
750# else
751# define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
752# endif
753#else /* CONFIG_X86_32 */
754# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
755#endif
756
757/*
758 * Find the highest page frame number we have available
759 */
760static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
761{
762 int i;
763 unsigned long last_pfn = 0;
764 unsigned long max_arch_pfn = MAX_ARCH_PFN;
765
766 for (i = 0; i < e820.nr_map; i++) {
767 struct e820entry *ei = &e820.map[i];
768 unsigned long start_pfn;
769 unsigned long end_pfn;
770
771 if (ei->type != type)
772 continue;
773
774 start_pfn = ei->addr >> PAGE_SHIFT;
775 end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
776
777 if (start_pfn >= limit_pfn)
778 continue;
779 if (end_pfn > limit_pfn) {
780 last_pfn = limit_pfn;
781 break;
782 }
783 if (end_pfn > last_pfn)
784 last_pfn = end_pfn;
785 }
786
787 if (last_pfn > max_arch_pfn)
788 last_pfn = max_arch_pfn;
789
790 printk(KERN_INFO "e820: last_pfn = %#lx max_arch_pfn = %#lx\n",
791 last_pfn, max_arch_pfn);
792 return last_pfn;
793}
794unsigned long __init e820_end_of_ram_pfn(void)
795{
796 return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
797}
798
799unsigned long __init e820_end_of_low_ram_pfn(void)
800{
801 return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
802}
803
804static void early_panic(char *msg)
805{
806 early_printk(msg);
807 panic(msg);
808}
809
810static int userdef __initdata;
811
812/* "mem=nopentium" disables the 4MB page tables. */
813static int __init parse_memopt(char *p)
814{
815 u64 mem_size;
816
817 if (!p)
818 return -EINVAL;
819
820 if (!strcmp(p, "nopentium")) {
821#ifdef CONFIG_X86_32
822 setup_clear_cpu_cap(X86_FEATURE_PSE);
823 return 0;
824#else
825 printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
826 return -EINVAL;
827#endif
828 }
829
830 userdef = 1;
831 mem_size = memparse(p, &p);
832 /* don't remove all of memory when handling "mem={invalid}" param */
833 if (mem_size == 0)
834 return -EINVAL;
835 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
836
837 return 0;
838}
839early_param("mem", parse_memopt);
840
841static int __init parse_memmap_one(char *p)
842{
843 char *oldp;
844 u64 start_at, mem_size;
845
846 if (!p)
847 return -EINVAL;
848
849 if (!strncmp(p, "exactmap", 8)) {
850#ifdef CONFIG_CRASH_DUMP
851 /*
852 * If we are doing a crash dump, we still need to know
853 * the real mem size before original memory map is
854 * reset.
855 */
856 saved_max_pfn = e820_end_of_ram_pfn();
857#endif
858 e820.nr_map = 0;
859 userdef = 1;
860 return 0;
861 }
862
863 oldp = p;
864 mem_size = memparse(p, &p);
865 if (p == oldp)
866 return -EINVAL;
867
868 userdef = 1;
869 if (*p == '@') {
870 start_at = memparse(p+1, &p);
871 e820_add_region(start_at, mem_size, E820_RAM);
872 } else if (*p == '#') {
873 start_at = memparse(p+1, &p);
874 e820_add_region(start_at, mem_size, E820_ACPI);
875 } else if (*p == '$') {
876 start_at = memparse(p+1, &p);
877 e820_add_region(start_at, mem_size, E820_RESERVED);
878 } else
879 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
880
881 return *p == '\0' ? 0 : -EINVAL;
882}
883static int __init parse_memmap_opt(char *str)
884{
885 while (str) {
886 char *k = strchr(str, ',');
887
888 if (k)
889 *k++ = 0;
890
891 parse_memmap_one(str);
892 str = k;
893 }
894
895 return 0;
896}
897early_param("memmap", parse_memmap_opt);
898
899void __init finish_e820_parsing(void)
900{
901 if (userdef) {
902 u32 nr = e820.nr_map;
903
904 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
905 early_panic("Invalid user supplied memory map");
906 e820.nr_map = nr;
907
908 printk(KERN_INFO "e820: user-defined physical RAM map:\n");
909 e820_print_map("user");
910 }
911}
912
913static inline const char *e820_type_to_string(int e820_type)
914{
915 switch (e820_type) {
916 case E820_RESERVED_KERN:
917 case E820_RAM: return "System RAM";
918 case E820_ACPI: return "ACPI Tables";
919 case E820_NVS: return "ACPI Non-volatile Storage";
920 case E820_UNUSABLE: return "Unusable memory";
921 default: return "reserved";
922 }
923}
924
925/*
926 * Mark e820 reserved areas as busy for the resource manager.
927 */
928static struct resource __initdata *e820_res;
929void __init e820_reserve_resources(void)
930{
931 int i;
932 struct resource *res;
933 u64 end;
934
935 res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
936 e820_res = res;
937 for (i = 0; i < e820.nr_map; i++) {
938 end = e820.map[i].addr + e820.map[i].size - 1;
939 if (end != (resource_size_t)end) {
940 res++;
941 continue;
942 }
943 res->name = e820_type_to_string(e820.map[i].type);
944 res->start = e820.map[i].addr;
945 res->end = end;
946
947 res->flags = IORESOURCE_MEM;
948
949 /*
950 * don't register the region that could be conflicted with
951 * pci device BAR resource and insert them later in
952 * pcibios_resource_survey()
953 */
954 if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
955 res->flags |= IORESOURCE_BUSY;
956 insert_resource(&iomem_resource, res);
957 }
958 res++;
959 }
960
961 for (i = 0; i < e820_saved.nr_map; i++) {
962 struct e820entry *entry = &e820_saved.map[i];
963 firmware_map_add_early(entry->addr,
964 entry->addr + entry->size,
965 e820_type_to_string(entry->type));
966 }
967}
968
969/* How much should we pad RAM ending depending on where it is? */
970static unsigned long ram_alignment(resource_size_t pos)
971{
972 unsigned long mb = pos >> 20;
973
974 /* To 64kB in the first megabyte */
975 if (!mb)
976 return 64*1024;
977
978 /* To 1MB in the first 16MB */
979 if (mb < 16)
980 return 1024*1024;
981
982 /* To 64MB for anything above that */
983 return 64*1024*1024;
984}
985
986#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
987
988void __init e820_reserve_resources_late(void)
989{
990 int i;
991 struct resource *res;
992
993 res = e820_res;
994 for (i = 0; i < e820.nr_map; i++) {
995 if (!res->parent && res->end)
996 insert_resource_expand_to_fit(&iomem_resource, res);
997 res++;
998 }
999
1000 /*
1001 * Try to bump up RAM regions to reasonable boundaries to
1002 * avoid stolen RAM:
1003 */
1004 for (i = 0; i < e820.nr_map; i++) {
1005 struct e820entry *entry = &e820.map[i];
1006 u64 start, end;
1007
1008 if (entry->type != E820_RAM)
1009 continue;
1010 start = entry->addr + entry->size;
1011 end = round_up(start, ram_alignment(start)) - 1;
1012 if (end > MAX_RESOURCE_SIZE)
1013 end = MAX_RESOURCE_SIZE;
1014 if (start >= end)
1015 continue;
1016 printk(KERN_DEBUG
1017 "e820: reserve RAM buffer [mem %#010llx-%#010llx]\n",
1018 start, end);
1019 reserve_region_with_split(&iomem_resource, start, end,
1020 "RAM buffer");
1021 }
1022}
1023
1024char *__init default_machine_specific_memory_setup(void)
1025{
1026 char *who = "BIOS-e820";
1027 u32 new_nr;
1028 /*
1029 * Try to copy the BIOS-supplied E820-map.
1030 *
1031 * Otherwise fake a memory map; one section from 0k->640k,
1032 * the next section from 1mb->appropriate_mem_k
1033 */
1034 new_nr = boot_params.e820_entries;
1035 sanitize_e820_map(boot_params.e820_map,
1036 ARRAY_SIZE(boot_params.e820_map),
1037 &new_nr);
1038 boot_params.e820_entries = new_nr;
1039 if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1040 < 0) {
1041 u64 mem_size;
1042
1043 /* compare results from other methods and take the greater */
1044 if (boot_params.alt_mem_k
1045 < boot_params.screen_info.ext_mem_k) {
1046 mem_size = boot_params.screen_info.ext_mem_k;
1047 who = "BIOS-88";
1048 } else {
1049 mem_size = boot_params.alt_mem_k;
1050 who = "BIOS-e801";
1051 }
1052
1053 e820.nr_map = 0;
1054 e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1055 e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1056 }
1057
1058 /* In case someone cares... */
1059 return who;
1060}
1061
1062void __init setup_memory_map(void)
1063{
1064 char *who;
1065
1066 who = x86_init.resources.memory_setup();
1067 memcpy(&e820_saved, &e820, sizeof(struct e820map));
1068 printk(KERN_INFO "e820: BIOS-provided physical RAM map:\n");
1069 e820_print_map(who);
1070}
1071
1072void __init memblock_x86_fill(void)
1073{
1074 int i;
1075 u64 end;
1076
1077 /*
1078 * EFI may have more than 128 entries
1079 * We are safe to enable resizing, beause memblock_x86_fill()
1080 * is rather later for x86
1081 */
1082 memblock_allow_resize();
1083
1084 for (i = 0; i < e820.nr_map; i++) {
1085 struct e820entry *ei = &e820.map[i];
1086
1087 end = ei->addr + ei->size;
1088 if (end != (resource_size_t)end)
1089 continue;
1090
1091 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
1092 continue;
1093
1094 memblock_add(ei->addr, ei->size);
1095 }
1096
1097 /* throw away partial pages */
1098 memblock_trim_memory(PAGE_SIZE);
1099
1100 memblock_dump_all();
1101}
1102
1103void __init memblock_find_dma_reserve(void)
1104{
1105#ifdef CONFIG_X86_64
1106 u64 nr_pages = 0, nr_free_pages = 0;
1107 unsigned long start_pfn, end_pfn;
1108 phys_addr_t start, end;
1109 int i;
1110 u64 u;
1111
1112 /*
1113 * need to find out used area below MAX_DMA_PFN
1114 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1115 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1116 */
1117 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
1118 start_pfn = min_t(unsigned long, start_pfn, MAX_DMA_PFN);
1119 end_pfn = min_t(unsigned long, end_pfn, MAX_DMA_PFN);
1120 nr_pages += end_pfn - start_pfn;
1121 }
1122
1123 for_each_free_mem_range(u, NUMA_NO_NODE, &start, &end, NULL) {
1124 start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN);
1125 end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN);
1126 if (start_pfn < end_pfn)
1127 nr_free_pages += end_pfn - start_pfn;
1128 }
1129
1130 set_dma_reserve(nr_pages - nr_free_pages);
1131#endif
1132}
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}