2 * Handle the memory map.
3 * The functions here do the job until bootmem takes over.
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>
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/init.h>
14 #include <linux/bootmem.h>
15 #include <linux/ioport.h>
16 #include <linux/string.h>
17 #include <linux/kexec.h>
18 #include <linux/module.h>
20 #include <linux/pfn.h>
21 #include <linux/suspend.h>
22 #include <linux/firmware-map.h>
24 #include <asm/pgtable.h>
27 #include <asm/proto.h>
28 #include <asm/setup.h>
29 #include <asm/trampoline.h>
32 * The e820 map is the map that gets modified e.g. with command line parameters
33 * and that is also registered with modifications in the kernel resource tree
34 * with the iomem_resource as parent.
36 * The e820_saved is directly saved after the BIOS-provided memory map is
37 * copied. It doesn't get modified afterwards. It's registered for the
38 * /sys/firmware/memmap interface.
40 * That memory map is not modified and is used as base for kexec. The kexec'd
41 * kernel should get the same memory map as the firmware provides. Then the
42 * user can e.g. boot the original kernel with mem=1G while still booting the
43 * next kernel with full memory.
46 struct e820map e820_saved;
48 /* For PCI or other memory-mapped resources */
49 unsigned long pci_mem_start = 0xaeedbabe;
51 EXPORT_SYMBOL(pci_mem_start);
55 * This function checks if any part of the range <start,end> is mapped
59 e820_any_mapped(u64 start, u64 end, unsigned type)
63 for (i = 0; i < e820.nr_map; i++) {
64 struct e820entry *ei = &e820.map[i];
66 if (type && ei->type != type)
68 if (ei->addr >= end || ei->addr + ei->size <= start)
74 EXPORT_SYMBOL_GPL(e820_any_mapped);
77 * This function checks if the entire range <start,end> is mapped with type.
79 * Note: this function only works correct if the e820 table is sorted and
80 * not-overlapping, which is the case
82 int __init e820_all_mapped(u64 start, u64 end, unsigned type)
86 for (i = 0; i < e820.nr_map; i++) {
87 struct e820entry *ei = &e820.map[i];
89 if (type && ei->type != type)
91 /* is the region (part) in overlap with the current region ?*/
92 if (ei->addr >= end || ei->addr + ei->size <= start)
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
98 if (ei->addr <= start)
99 start = ei->addr + ei->size;
101 * if start is now at or beyond end, we're done, full
111 * Add a memory region to the kernel e820 map.
113 void __init e820_add_region(u64 start, u64 size, int type)
117 if (x == ARRAY_SIZE(e820.map)) {
118 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
122 e820.map[x].addr = start;
123 e820.map[x].size = size;
124 e820.map[x].type = type;
128 void __init e820_print_map(char *who)
132 for (i = 0; i < e820.nr_map; i++) {
133 printk(KERN_INFO " %s: %016Lx - %016Lx ", who,
134 (unsigned long long) e820.map[i].addr,
136 (e820.map[i].addr + e820.map[i].size));
137 switch (e820.map[i].type) {
139 case E820_RESERVED_KERN:
140 printk(KERN_CONT "(usable)\n");
143 printk(KERN_CONT "(reserved)\n");
146 printk(KERN_CONT "(ACPI data)\n");
149 printk(KERN_CONT "(ACPI NVS)\n");
152 printk("(unusable)\n");
155 printk(KERN_CONT "type %u\n", e820.map[i].type);
162 * Sanitize the BIOS e820 map.
164 * Some e820 responses include overlapping entries. The following
165 * replaces the original e820 map with a new one, removing overlaps,
166 * and resolving conflicting memory types in favor of highest
169 * The input parameter biosmap points to an array of 'struct
170 * e820entry' which on entry has elements in the range [0, *pnr_map)
171 * valid, and which has space for up to max_nr_map entries.
172 * On return, the resulting sanitized e820 map entries will be in
173 * overwritten in the same location, starting at biosmap.
175 * The integer pointed to by pnr_map must be valid on entry (the
176 * current number of valid entries located at biosmap) and will
177 * be updated on return, with the new number of valid entries
178 * (something no more than max_nr_map.)
180 * The return value from sanitize_e820_map() is zero if it
181 * successfully 'sanitized' the map entries passed in, and is -1
182 * if it did nothing, which can happen if either of (1) it was
183 * only passed one map entry, or (2) any of the input map entries
184 * were invalid (start + size < start, meaning that the size was
185 * so big the described memory range wrapped around through zero.)
187 * Visually we're performing the following
188 * (1,2,3,4 = memory types)...
190 * Sample memory map (w/overlaps):
191 * ____22__________________
192 * ______________________4_
193 * ____1111________________
194 * _44_____________________
195 * 11111111________________
196 * ____________________33__
197 * ___________44___________
198 * __________33333_________
199 * ______________22________
200 * ___________________2222_
201 * _________111111111______
202 * _____________________11_
203 * _________________4______
205 * Sanitized equivalent (no overlap):
206 * 1_______________________
207 * _44_____________________
208 * ___1____________________
209 * ____22__________________
210 * ______11________________
211 * _________1______________
212 * __________3_____________
213 * ___________44___________
214 * _____________33_________
215 * _______________2________
216 * ________________1_______
217 * _________________4______
218 * ___________________2____
219 * ____________________33__
220 * ______________________4_
223 int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
226 struct change_member {
227 struct e820entry *pbios; /* pointer to original bios entry */
228 unsigned long long addr; /* address for this change point */
230 static struct change_member change_point_list[2*E820_X_MAX] __initdata;
231 static struct change_member *change_point[2*E820_X_MAX] __initdata;
232 static struct e820entry *overlap_list[E820_X_MAX] __initdata;
233 static struct e820entry new_bios[E820_X_MAX] __initdata;
234 struct change_member *change_tmp;
235 unsigned long current_type, last_type;
236 unsigned long long last_addr;
237 int chgidx, still_changing;
240 int old_nr, new_nr, chg_nr;
243 /* if there's only one memory region, don't bother */
248 BUG_ON(old_nr > max_nr_map);
250 /* bail out if we find any unreasonable addresses in bios map */
251 for (i = 0; i < old_nr; i++)
252 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
255 /* create pointers for initial change-point information (for sorting) */
256 for (i = 0; i < 2 * old_nr; i++)
257 change_point[i] = &change_point_list[i];
259 /* record all known change-points (starting and ending addresses),
260 omitting those that are for empty memory regions */
262 for (i = 0; i < old_nr; i++) {
263 if (biosmap[i].size != 0) {
264 change_point[chgidx]->addr = biosmap[i].addr;
265 change_point[chgidx++]->pbios = &biosmap[i];
266 change_point[chgidx]->addr = biosmap[i].addr +
268 change_point[chgidx++]->pbios = &biosmap[i];
273 /* sort change-point list by memory addresses (low -> high) */
275 while (still_changing) {
277 for (i = 1; i < chg_nr; i++) {
278 unsigned long long curaddr, lastaddr;
279 unsigned long long curpbaddr, lastpbaddr;
281 curaddr = change_point[i]->addr;
282 lastaddr = change_point[i - 1]->addr;
283 curpbaddr = change_point[i]->pbios->addr;
284 lastpbaddr = change_point[i - 1]->pbios->addr;
287 * swap entries, when:
289 * curaddr > lastaddr or
290 * curaddr == lastaddr and curaddr == curpbaddr and
291 * lastaddr != lastpbaddr
293 if (curaddr < lastaddr ||
294 (curaddr == lastaddr && curaddr == curpbaddr &&
295 lastaddr != lastpbaddr)) {
296 change_tmp = change_point[i];
297 change_point[i] = change_point[i-1];
298 change_point[i-1] = change_tmp;
304 /* create a new bios memory map, removing overlaps */
305 overlap_entries = 0; /* number of entries in the overlap table */
306 new_bios_entry = 0; /* index for creating new bios map entries */
307 last_type = 0; /* start with undefined memory type */
308 last_addr = 0; /* start with 0 as last starting address */
310 /* loop through change-points, determining affect on the new bios map */
311 for (chgidx = 0; chgidx < chg_nr; chgidx++) {
312 /* keep track of all overlapping bios entries */
313 if (change_point[chgidx]->addr ==
314 change_point[chgidx]->pbios->addr) {
316 * add map entry to overlap list (> 1 entry
317 * implies an overlap)
319 overlap_list[overlap_entries++] =
320 change_point[chgidx]->pbios;
323 * remove entry from list (order independent,
326 for (i = 0; i < overlap_entries; i++) {
327 if (overlap_list[i] ==
328 change_point[chgidx]->pbios)
330 overlap_list[overlap_entries-1];
335 * if there are overlapping entries, decide which
336 * "type" to use (larger value takes precedence --
337 * 1=usable, 2,3,4,4+=unusable)
340 for (i = 0; i < overlap_entries; i++)
341 if (overlap_list[i]->type > current_type)
342 current_type = overlap_list[i]->type;
344 * continue building up new bios map based on this
347 if (current_type != last_type) {
348 if (last_type != 0) {
349 new_bios[new_bios_entry].size =
350 change_point[chgidx]->addr - last_addr;
352 * move forward only if the new size
355 if (new_bios[new_bios_entry].size != 0)
357 * no more space left for new
360 if (++new_bios_entry >= max_nr_map)
363 if (current_type != 0) {
364 new_bios[new_bios_entry].addr =
365 change_point[chgidx]->addr;
366 new_bios[new_bios_entry].type = current_type;
367 last_addr = change_point[chgidx]->addr;
369 last_type = current_type;
372 /* retain count for new bios entries */
373 new_nr = new_bios_entry;
375 /* copy new bios mapping into original location */
376 memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
382 static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
385 u64 start = biosmap->addr;
386 u64 size = biosmap->size;
387 u64 end = start + size;
388 u32 type = biosmap->type;
390 /* Overflow in 64 bits? Ignore the memory map. */
394 e820_add_region(start, size, type);
403 * Copy the BIOS e820 map into a safe place.
405 * Sanity-check it while we're at it..
407 * If we're lucky and live on a modern system, the setup code
408 * will have given us a memory map that we can use to properly
409 * set up memory. If we aren't, we'll fake a memory map.
411 static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
413 /* Only one memory region (or negative)? Ignore it */
417 return __append_e820_map(biosmap, nr_map);
420 static u64 __init e820_update_range_map(struct e820map *e820x, u64 start,
421 u64 size, unsigned old_type,
425 u64 real_updated_size = 0;
427 BUG_ON(old_type == new_type);
429 if (size > (ULLONG_MAX - start))
430 size = ULLONG_MAX - start;
432 for (i = 0; i < e820x->nr_map; i++) {
433 struct e820entry *ei = &e820x->map[i];
434 u64 final_start, final_end;
435 if (ei->type != old_type)
437 /* totally covered? */
438 if (ei->addr >= start &&
439 (ei->addr + ei->size) <= (start + size)) {
441 real_updated_size += ei->size;
444 /* partially covered */
445 final_start = max(start, ei->addr);
446 final_end = min(start + size, ei->addr + ei->size);
447 if (final_start >= final_end)
451 if (x == ARRAY_SIZE(e820x->map)) {
452 printk(KERN_ERR "Too many memory map entries!\n");
455 e820x->map[x].addr = final_start;
456 e820x->map[x].size = final_end - final_start;
457 e820x->map[x].type = new_type;
460 real_updated_size += final_end - final_start;
462 if (ei->addr < final_start)
464 ei->addr = final_end;
465 ei->size -= final_end - final_start;
467 return real_updated_size;
470 u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
473 return e820_update_range_map(&e820, start, size, old_type, new_type);
476 static u64 __init e820_update_range_saved(u64 start, u64 size,
477 unsigned old_type, unsigned new_type)
479 return e820_update_range_map(&e820_saved, start, size, old_type,
483 /* make e820 not cover the range */
484 u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
488 u64 real_removed_size = 0;
490 if (size > (ULLONG_MAX - start))
491 size = ULLONG_MAX - start;
493 for (i = 0; i < e820.nr_map; i++) {
494 struct e820entry *ei = &e820.map[i];
495 u64 final_start, final_end;
497 if (checktype && ei->type != old_type)
499 /* totally covered? */
500 if (ei->addr >= start &&
501 (ei->addr + ei->size) <= (start + size)) {
502 real_removed_size += ei->size;
503 memset(ei, 0, sizeof(struct e820entry));
506 /* partially covered */
507 final_start = max(start, ei->addr);
508 final_end = min(start + size, ei->addr + ei->size);
509 if (final_start >= final_end)
511 real_removed_size += final_end - final_start;
513 ei->size -= final_end - final_start;
514 if (ei->addr < final_start)
516 ei->addr = final_end;
518 return real_removed_size;
521 void __init update_e820(void)
525 nr_map = e820.nr_map;
526 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr_map))
528 e820.nr_map = nr_map;
529 printk(KERN_INFO "modified physical RAM map:\n");
530 e820_print_map("modified");
532 static void __init update_e820_saved(void)
536 nr_map = e820_saved.nr_map;
537 if (sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map), &nr_map))
539 e820_saved.nr_map = nr_map;
541 #define MAX_GAP_END 0x100000000ull
543 * Search for a gap in the e820 memory space from start_addr to end_addr.
545 __init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
546 unsigned long start_addr, unsigned long long end_addr)
548 unsigned long long last;
552 last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
555 unsigned long long start = e820.map[i].addr;
556 unsigned long long end = start + e820.map[i].size;
558 if (end < start_addr)
562 * Since "last" is at most 4GB, we know we'll
563 * fit in 32 bits if this condition is true
566 unsigned long gap = last - end;
568 if (gap >= *gapsize) {
581 * Search for the biggest gap in the low 32 bits of the e820
582 * memory space. We pass this space to PCI to assign MMIO resources
583 * for hotplug or unconfigured devices in.
584 * Hopefully the BIOS let enough space left.
586 __init void e820_setup_gap(void)
588 unsigned long gapstart, gapsize, round;
591 gapstart = 0x10000000;
593 found = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
597 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
598 printk(KERN_ERR "PCI: Warning: Cannot find a gap in the 32bit "
600 KERN_ERR "PCI: Unassigned devices with 32bit resource "
601 "registers may break!\n");
606 * See how much we want to round up: start off with
607 * rounding to the next 1MB area.
610 while ((gapsize >> 4) > round)
612 /* Fun with two's complement */
613 pci_mem_start = (gapstart + round) & -round;
616 "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
617 pci_mem_start, gapstart, gapsize);
621 * Because of the size limitation of struct boot_params, only first
622 * 128 E820 memory entries are passed to kernel via
623 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
624 * linked list of struct setup_data, which is parsed here.
626 void __init parse_e820_ext(struct setup_data *sdata, unsigned long pa_data)
630 struct e820entry *extmap;
632 entries = sdata->len / sizeof(struct e820entry);
633 map_len = sdata->len + sizeof(struct setup_data);
634 if (map_len > PAGE_SIZE)
635 sdata = early_ioremap(pa_data, map_len);
636 extmap = (struct e820entry *)(sdata->data);
637 __append_e820_map(extmap, entries);
638 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
639 if (map_len > PAGE_SIZE)
640 early_iounmap(sdata, map_len);
641 printk(KERN_INFO "extended physical RAM map:\n");
642 e820_print_map("extended");
645 #if defined(CONFIG_X86_64) || \
646 (defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
648 * Find the ranges of physical addresses that do not correspond to
649 * e820 RAM areas and mark the corresponding pages as nosave for
650 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
652 * This function requires the e820 map to be sorted and without any
653 * overlapping entries and assumes the first e820 area to be RAM.
655 void __init e820_mark_nosave_regions(unsigned long limit_pfn)
660 pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
661 for (i = 1; i < e820.nr_map; i++) {
662 struct e820entry *ei = &e820.map[i];
664 if (pfn < PFN_UP(ei->addr))
665 register_nosave_region(pfn, PFN_UP(ei->addr));
667 pfn = PFN_DOWN(ei->addr + ei->size);
668 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
669 register_nosave_region(PFN_UP(ei->addr), pfn);
671 if (pfn >= limit_pfn)
677 #ifdef CONFIG_HIBERNATION
679 * Mark ACPI NVS memory region, so that we can save/restore it during
680 * hibernation and the subsequent resume.
682 static int __init e820_mark_nvs_memory(void)
686 for (i = 0; i < e820.nr_map; i++) {
687 struct e820entry *ei = &e820.map[i];
689 if (ei->type == E820_NVS)
690 hibernate_nvs_register(ei->addr, ei->size);
695 core_initcall(e820_mark_nvs_memory);
699 * Early reserved memory areas.
701 #define MAX_EARLY_RES 20
708 static struct early_res early_res[MAX_EARLY_RES] __initdata = {
709 { 0, PAGE_SIZE, "BIOS data page" }, /* BIOS data page */
713 static int __init find_overlapped_early(u64 start, u64 end)
718 for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
720 if (end > r->start && start < r->end)
728 * Drop the i-th range from the early reservation map,
729 * by copying any higher ranges down one over it, and
730 * clearing what had been the last slot.
732 static void __init drop_range(int i)
736 for (j = i + 1; j < MAX_EARLY_RES && early_res[j].end; j++)
739 memmove(&early_res[i], &early_res[i + 1],
740 (j - 1 - i) * sizeof(struct early_res));
742 early_res[j - 1].end = 0;
746 * Split any existing ranges that:
747 * 1) are marked 'overlap_ok', and
748 * 2) overlap with the stated range [start, end)
749 * into whatever portion (if any) of the existing range is entirely
750 * below or entirely above the stated range. Drop the portion
751 * of the existing range that overlaps with the stated range,
752 * which will allow the caller of this routine to then add that
753 * stated range without conflicting with any existing range.
755 static void __init drop_overlaps_that_are_ok(u64 start, u64 end)
759 u64 lower_start, lower_end;
760 u64 upper_start, upper_end;
763 for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
766 /* Continue past non-overlapping ranges */
767 if (end <= r->start || start >= r->end)
771 * Leave non-ok overlaps as is; let caller
772 * panic "Overlapping early reservations"
773 * when it hits this overlap.
779 * We have an ok overlap. We will drop it from the early
780 * reservation map, and add back in any non-overlapping
781 * portions (lower or upper) as separate, overlap_ok,
782 * non-overlapping ranges.
785 /* 1. Note any non-overlapping (lower or upper) ranges. */
786 strncpy(name, r->name, sizeof(name) - 1);
788 lower_start = lower_end = 0;
789 upper_start = upper_end = 0;
790 if (r->start < start) {
791 lower_start = r->start;
799 /* 2. Drop the original ok overlapping range */
802 i--; /* resume for-loop on copied down entry */
804 /* 3. Add back in any non-overlapping ranges. */
806 reserve_early_overlap_ok(lower_start, lower_end, name);
808 reserve_early_overlap_ok(upper_start, upper_end, name);
812 static void __init __reserve_early(u64 start, u64 end, char *name,
818 i = find_overlapped_early(start, end);
819 if (i >= MAX_EARLY_RES)
820 panic("Too many early reservations");
823 panic("Overlapping early reservations "
824 "%llx-%llx %s to %llx-%llx %s\n",
825 start, end - 1, name?name:"", r->start,
826 r->end - 1, r->name);
829 r->overlap_ok = overlap_ok;
831 strncpy(r->name, name, sizeof(r->name) - 1);
835 * A few early reservtations come here.
837 * The 'overlap_ok' in the name of this routine does -not- mean it
838 * is ok for these reservations to overlap an earlier reservation.
839 * Rather it means that it is ok for subsequent reservations to
842 * Use this entry point to reserve early ranges when you are doing
843 * so out of "Paranoia", reserving perhaps more memory than you need,
844 * just in case, and don't mind a subsequent overlapping reservation
845 * that is known to be needed.
847 * The drop_overlaps_that_are_ok() call here isn't really needed.
848 * It would be needed if we had two colliding 'overlap_ok'
849 * reservations, so that the second such would not panic on the
850 * overlap with the first. We don't have any such as of this
851 * writing, but might as well tolerate such if it happens in
854 void __init reserve_early_overlap_ok(u64 start, u64 end, char *name)
856 drop_overlaps_that_are_ok(start, end);
857 __reserve_early(start, end, name, 1);
861 * Most early reservations come here.
863 * We first have drop_overlaps_that_are_ok() drop any pre-existing
864 * 'overlap_ok' ranges, so that we can then reserve this memory
865 * range without risk of panic'ing on an overlapping overlap_ok
868 void __init reserve_early(u64 start, u64 end, char *name)
873 drop_overlaps_that_are_ok(start, end);
874 __reserve_early(start, end, name, 0);
877 void __init free_early(u64 start, u64 end)
882 i = find_overlapped_early(start, end);
884 if (i >= MAX_EARLY_RES || r->end != end || r->start != start)
885 panic("free_early on not reserved area: %llx-%llx!",
891 void __init early_res_to_bootmem(u64 start, u64 end)
894 u64 final_start, final_end;
897 for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++)
900 printk(KERN_INFO "(%d early reservations) ==> bootmem [%010llx - %010llx]\n",
902 for (i = 0; i < count; i++) {
903 struct early_res *r = &early_res[i];
904 printk(KERN_INFO " #%d [%010llx - %010llx] %16s", i,
905 r->start, r->end, r->name);
906 final_start = max(start, r->start);
907 final_end = min(end, r->end);
908 if (final_start >= final_end) {
909 printk(KERN_CONT "\n");
912 printk(KERN_CONT " ==> [%010llx - %010llx]\n",
913 final_start, final_end);
914 reserve_bootmem_generic(final_start, final_end - final_start,
919 /* Check for already reserved areas */
920 static inline int __init bad_addr(u64 *addrp, u64 size, u64 align)
927 i = find_overlapped_early(addr, addr + size);
929 if (i < MAX_EARLY_RES && r->end) {
930 *addrp = addr = round_up(r->end, align);
937 /* Check for already reserved areas */
938 static inline int __init bad_addr_size(u64 *addrp, u64 *sizep, u64 align)
941 u64 addr = *addrp, last;
946 for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
947 struct early_res *r = &early_res[i];
948 if (last > r->start && addr < r->start) {
949 size = r->start - addr;
953 if (last > r->end && addr < r->end) {
954 addr = round_up(r->end, align);
959 if (last <= r->end && addr >= r->start) {
972 * Find a free area with specified alignment in a specific range.
974 u64 __init find_e820_area(u64 start, u64 end, u64 size, u64 align)
978 for (i = 0; i < e820.nr_map; i++) {
979 struct e820entry *ei = &e820.map[i];
983 if (ei->type != E820_RAM)
985 addr = round_up(ei->addr, align);
986 ei_last = ei->addr + ei->size;
988 addr = round_up(start, align);
991 while (bad_addr(&addr, size, align) && addr+size <= ei_last)
1004 * Find next free range after *start
1006 u64 __init find_e820_area_size(u64 start, u64 *sizep, u64 align)
1010 for (i = 0; i < e820.nr_map; i++) {
1011 struct e820entry *ei = &e820.map[i];
1015 if (ei->type != E820_RAM)
1017 addr = round_up(ei->addr, align);
1018 ei_last = ei->addr + ei->size;
1020 addr = round_up(start, align);
1021 if (addr >= ei_last)
1023 *sizep = ei_last - addr;
1024 while (bad_addr_size(&addr, sizep, align) &&
1025 addr + *sizep <= ei_last)
1027 last = addr + *sizep;
1037 * pre allocated 4k and reserved it in e820
1039 u64 __init early_reserve_e820(u64 startt, u64 sizet, u64 align)
1046 while (size < sizet && (start + 1))
1047 start = find_e820_area_size(start, &size, align);
1052 #ifdef CONFIG_X86_32
1053 if (start >= MAXMEM)
1055 if (start + size > MAXMEM)
1056 size = MAXMEM - start;
1059 addr = round_down(start + size - sizet, align);
1062 e820_update_range(addr, sizet, E820_RAM, E820_RESERVED);
1063 e820_update_range_saved(addr, sizet, E820_RAM, E820_RESERVED);
1064 printk(KERN_INFO "update e820 for early_reserve_e820\n");
1066 update_e820_saved();
1071 #ifdef CONFIG_X86_32
1072 # ifdef CONFIG_X86_PAE
1073 # define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
1075 # define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
1077 #else /* CONFIG_X86_32 */
1078 # define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
1082 * Find the highest page frame number we have available
1084 static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
1087 unsigned long last_pfn = 0;
1088 unsigned long max_arch_pfn = MAX_ARCH_PFN;
1090 for (i = 0; i < e820.nr_map; i++) {
1091 struct e820entry *ei = &e820.map[i];
1092 unsigned long start_pfn;
1093 unsigned long end_pfn;
1095 if (ei->type != type)
1098 start_pfn = ei->addr >> PAGE_SHIFT;
1099 end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
1101 if (start_pfn >= limit_pfn)
1103 if (end_pfn > limit_pfn) {
1104 last_pfn = limit_pfn;
1107 if (end_pfn > last_pfn)
1111 if (last_pfn > max_arch_pfn)
1112 last_pfn = max_arch_pfn;
1114 printk(KERN_INFO "last_pfn = %#lx max_arch_pfn = %#lx\n",
1115 last_pfn, max_arch_pfn);
1118 unsigned long __init e820_end_of_ram_pfn(void)
1120 return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
1123 unsigned long __init e820_end_of_low_ram_pfn(void)
1125 return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
1128 * Finds an active region in the address range from start_pfn to last_pfn and
1129 * returns its range in ei_startpfn and ei_endpfn for the e820 entry.
1131 int __init e820_find_active_region(const struct e820entry *ei,
1132 unsigned long start_pfn,
1133 unsigned long last_pfn,
1134 unsigned long *ei_startpfn,
1135 unsigned long *ei_endpfn)
1137 u64 align = PAGE_SIZE;
1139 *ei_startpfn = round_up(ei->addr, align) >> PAGE_SHIFT;
1140 *ei_endpfn = round_down(ei->addr + ei->size, align) >> PAGE_SHIFT;
1142 /* Skip map entries smaller than a page */
1143 if (*ei_startpfn >= *ei_endpfn)
1146 /* Skip if map is outside the node */
1147 if (ei->type != E820_RAM || *ei_endpfn <= start_pfn ||
1148 *ei_startpfn >= last_pfn)
1151 /* Check for overlaps */
1152 if (*ei_startpfn < start_pfn)
1153 *ei_startpfn = start_pfn;
1154 if (*ei_endpfn > last_pfn)
1155 *ei_endpfn = last_pfn;
1160 /* Walk the e820 map and register active regions within a node */
1161 void __init e820_register_active_regions(int nid, unsigned long start_pfn,
1162 unsigned long last_pfn)
1164 unsigned long ei_startpfn;
1165 unsigned long ei_endpfn;
1168 for (i = 0; i < e820.nr_map; i++)
1169 if (e820_find_active_region(&e820.map[i],
1170 start_pfn, last_pfn,
1171 &ei_startpfn, &ei_endpfn))
1172 add_active_range(nid, ei_startpfn, ei_endpfn);
1176 * Find the hole size (in bytes) in the memory range.
1177 * @start: starting address of the memory range to scan
1178 * @end: ending address of the memory range to scan
1180 u64 __init e820_hole_size(u64 start, u64 end)
1182 unsigned long start_pfn = start >> PAGE_SHIFT;
1183 unsigned long last_pfn = end >> PAGE_SHIFT;
1184 unsigned long ei_startpfn, ei_endpfn, ram = 0;
1187 for (i = 0; i < e820.nr_map; i++) {
1188 if (e820_find_active_region(&e820.map[i],
1189 start_pfn, last_pfn,
1190 &ei_startpfn, &ei_endpfn))
1191 ram += ei_endpfn - ei_startpfn;
1193 return end - start - ((u64)ram << PAGE_SHIFT);
1196 static void early_panic(char *msg)
1202 static int userdef __initdata;
1204 /* "mem=nopentium" disables the 4MB page tables. */
1205 static int __init parse_memopt(char *p)
1212 #ifdef CONFIG_X86_32
1213 if (!strcmp(p, "nopentium")) {
1214 setup_clear_cpu_cap(X86_FEATURE_PSE);
1220 mem_size = memparse(p, &p);
1221 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
1225 early_param("mem", parse_memopt);
1227 static int __init parse_memmap_opt(char *p)
1230 u64 start_at, mem_size;
1235 if (!strncmp(p, "exactmap", 8)) {
1236 #ifdef CONFIG_CRASH_DUMP
1238 * If we are doing a crash dump, we still need to know
1239 * the real mem size before original memory map is
1242 saved_max_pfn = e820_end_of_ram_pfn();
1250 mem_size = memparse(p, &p);
1256 start_at = memparse(p+1, &p);
1257 e820_add_region(start_at, mem_size, E820_RAM);
1258 } else if (*p == '#') {
1259 start_at = memparse(p+1, &p);
1260 e820_add_region(start_at, mem_size, E820_ACPI);
1261 } else if (*p == '$') {
1262 start_at = memparse(p+1, &p);
1263 e820_add_region(start_at, mem_size, E820_RESERVED);
1265 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
1267 return *p == '\0' ? 0 : -EINVAL;
1269 early_param("memmap", parse_memmap_opt);
1271 void __init finish_e820_parsing(void)
1274 int nr = e820.nr_map;
1276 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
1277 early_panic("Invalid user supplied memory map");
1280 printk(KERN_INFO "user-defined physical RAM map:\n");
1281 e820_print_map("user");
1285 static inline const char *e820_type_to_string(int e820_type)
1287 switch (e820_type) {
1288 case E820_RESERVED_KERN:
1289 case E820_RAM: return "System RAM";
1290 case E820_ACPI: return "ACPI Tables";
1291 case E820_NVS: return "ACPI Non-volatile Storage";
1292 case E820_UNUSABLE: return "Unusable memory";
1293 default: return "reserved";
1298 * Mark e820 reserved areas as busy for the resource manager.
1300 static struct resource __initdata *e820_res;
1301 void __init e820_reserve_resources(void)
1304 struct resource *res;
1307 res = alloc_bootmem_low(sizeof(struct resource) * e820.nr_map);
1309 for (i = 0; i < e820.nr_map; i++) {
1310 end = e820.map[i].addr + e820.map[i].size - 1;
1311 if (end != (resource_size_t)end) {
1315 res->name = e820_type_to_string(e820.map[i].type);
1316 res->start = e820.map[i].addr;
1319 res->flags = IORESOURCE_MEM;
1322 * don't register the region that could be conflicted with
1323 * pci device BAR resource and insert them later in
1324 * pcibios_resource_survey()
1326 if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
1327 res->flags |= IORESOURCE_BUSY;
1328 insert_resource(&iomem_resource, res);
1333 for (i = 0; i < e820_saved.nr_map; i++) {
1334 struct e820entry *entry = &e820_saved.map[i];
1335 firmware_map_add_early(entry->addr,
1336 entry->addr + entry->size - 1,
1337 e820_type_to_string(entry->type));
1341 void __init e820_reserve_resources_late(void)
1344 struct resource *res;
1347 for (i = 0; i < e820.nr_map; i++) {
1348 if (!res->parent && res->end)
1349 insert_resource_expand_to_fit(&iomem_resource, res);
1354 char *__init default_machine_specific_memory_setup(void)
1356 char *who = "BIOS-e820";
1359 * Try to copy the BIOS-supplied E820-map.
1361 * Otherwise fake a memory map; one section from 0k->640k,
1362 * the next section from 1mb->appropriate_mem_k
1364 new_nr = boot_params.e820_entries;
1365 sanitize_e820_map(boot_params.e820_map,
1366 ARRAY_SIZE(boot_params.e820_map),
1368 boot_params.e820_entries = new_nr;
1369 if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1373 /* compare results from other methods and take the greater */
1374 if (boot_params.alt_mem_k
1375 < boot_params.screen_info.ext_mem_k) {
1376 mem_size = boot_params.screen_info.ext_mem_k;
1379 mem_size = boot_params.alt_mem_k;
1384 e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1385 e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1388 /* In case someone cares... */
1392 char *__init __attribute__((weak)) machine_specific_memory_setup(void)
1394 if (x86_quirks->arch_memory_setup) {
1395 char *who = x86_quirks->arch_memory_setup();
1400 return default_machine_specific_memory_setup();
1403 /* Overridden in paravirt.c if CONFIG_PARAVIRT */
1404 char * __init __attribute__((weak)) memory_setup(void)
1406 return machine_specific_memory_setup();
1409 void __init setup_memory_map(void)
1413 who = memory_setup();
1414 memcpy(&e820_saved, &e820, sizeof(struct e820map));
1415 printk(KERN_INFO "BIOS-provided physical RAM map:\n");
1416 e820_print_map(who);