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-rw-r--r--arch/x86/kernel/e820.c370
1 files changed, 58 insertions, 312 deletions
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index d17d482a04f4..7bca3c6a02fb 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -12,21 +12,13 @@
12#include <linux/types.h> 12#include <linux/types.h>
13#include <linux/init.h> 13#include <linux/init.h>
14#include <linux/bootmem.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>
19#include <linux/mm.h>
20#include <linux/pfn.h> 15#include <linux/pfn.h>
21#include <linux/suspend.h> 16#include <linux/suspend.h>
22#include <linux/firmware-map.h> 17#include <linux/firmware-map.h>
23 18
24#include <asm/pgtable.h>
25#include <asm/page.h>
26#include <asm/e820.h> 19#include <asm/e820.h>
27#include <asm/proto.h> 20#include <asm/proto.h>
28#include <asm/setup.h> 21#include <asm/setup.h>
29#include <asm/trampoline.h>
30 22
31/* 23/*
32 * The e820 map is the map that gets modified e.g. with command line parameters 24 * The e820 map is the map that gets modified e.g. with command line parameters
@@ -517,31 +509,55 @@ u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
517 int checktype) 509 int checktype)
518{ 510{
519 int i; 511 int i;
512 u64 end;
520 u64 real_removed_size = 0; 513 u64 real_removed_size = 0;
521 514
522 if (size > (ULLONG_MAX - start)) 515 if (size > (ULLONG_MAX - start))
523 size = ULLONG_MAX - start; 516 size = ULLONG_MAX - start;
524 517
518 end = start + size;
519 printk(KERN_DEBUG "e820 remove range: %016Lx - %016Lx ",
520 (unsigned long long) start,
521 (unsigned long long) end);
522 if (checktype)
523 e820_print_type(old_type);
524 printk(KERN_CONT "\n");
525
525 for (i = 0; i < e820.nr_map; i++) { 526 for (i = 0; i < e820.nr_map; i++) {
526 struct e820entry *ei = &e820.map[i]; 527 struct e820entry *ei = &e820.map[i];
527 u64 final_start, final_end; 528 u64 final_start, final_end;
529 u64 ei_end;
528 530
529 if (checktype && ei->type != old_type) 531 if (checktype && ei->type != old_type)
530 continue; 532 continue;
533
534 ei_end = ei->addr + ei->size;
531 /* totally covered? */ 535 /* totally covered? */
532 if (ei->addr >= start && 536 if (ei->addr >= start && ei_end <= end) {
533 (ei->addr + ei->size) <= (start + size)) {
534 real_removed_size += ei->size; 537 real_removed_size += ei->size;
535 memset(ei, 0, sizeof(struct e820entry)); 538 memset(ei, 0, sizeof(struct e820entry));
536 continue; 539 continue;
537 } 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
538 /* partially covered */ 550 /* partially covered */
539 final_start = max(start, ei->addr); 551 final_start = max(start, ei->addr);
540 final_end = min(start + size, ei->addr + ei->size); 552 final_end = min(end, ei_end);
541 if (final_start >= final_end) 553 if (final_start >= final_end)
542 continue; 554 continue;
543 real_removed_size += final_end - final_start; 555 real_removed_size += final_end - final_start;
544 556
557 /*
558 * left range could be head or tail, so need to update
559 * size at first.
560 */
545 ei->size -= final_end - final_start; 561 ei->size -= final_end - final_start;
546 if (ei->addr < final_start) 562 if (ei->addr < final_start)
547 continue; 563 continue;
@@ -722,310 +738,44 @@ core_initcall(e820_mark_nvs_memory);
722#endif 738#endif
723 739
724/* 740/*
725 * Early reserved memory areas. 741 * Find a free area with specified alignment in a specific range.
726 */
727#define MAX_EARLY_RES 20
728
729struct early_res {
730 u64 start, end;
731 char name[16];
732 char overlap_ok;
733};
734static struct early_res early_res[MAX_EARLY_RES] __initdata = {
735 { 0, PAGE_SIZE, "BIOS data page" }, /* BIOS data page */
736 {}
737};
738
739static int __init find_overlapped_early(u64 start, u64 end)
740{
741 int i;
742 struct early_res *r;
743
744 for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
745 r = &early_res[i];
746 if (end > r->start && start < r->end)
747 break;
748 }
749
750 return i;
751}
752
753/*
754 * Drop the i-th range from the early reservation map,
755 * by copying any higher ranges down one over it, and
756 * clearing what had been the last slot.
757 */
758static void __init drop_range(int i)
759{
760 int j;
761
762 for (j = i + 1; j < MAX_EARLY_RES && early_res[j].end; j++)
763 ;
764
765 memmove(&early_res[i], &early_res[i + 1],
766 (j - 1 - i) * sizeof(struct early_res));
767
768 early_res[j - 1].end = 0;
769}
770
771/*
772 * Split any existing ranges that:
773 * 1) are marked 'overlap_ok', and
774 * 2) overlap with the stated range [start, end)
775 * into whatever portion (if any) of the existing range is entirely
776 * below or entirely above the stated range. Drop the portion
777 * of the existing range that overlaps with the stated range,
778 * which will allow the caller of this routine to then add that
779 * stated range without conflicting with any existing range.
780 */ 742 */
781static void __init drop_overlaps_that_are_ok(u64 start, u64 end) 743u64 __init find_e820_area(u64 start, u64 end, u64 size, u64 align)
782{ 744{
783 int i; 745 int i;
784 struct early_res *r;
785 u64 lower_start, lower_end;
786 u64 upper_start, upper_end;
787 char name[16];
788 746
789 for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) { 747 for (i = 0; i < e820.nr_map; i++) {
790 r = &early_res[i]; 748 struct e820entry *ei = &e820.map[i];
749 u64 addr;
750 u64 ei_start, ei_last;
791 751
792 /* Continue past non-overlapping ranges */ 752 if (ei->type != E820_RAM)
793 if (end <= r->start || start >= r->end)
794 continue; 753 continue;
795 754
796 /* 755 ei_last = ei->addr + ei->size;
797 * Leave non-ok overlaps as is; let caller 756 ei_start = ei->addr;
798 * panic "Overlapping early reservations" 757 addr = find_early_area(ei_start, ei_last, start, end,
799 * when it hits this overlap. 758 size, align);
800 */
801 if (!r->overlap_ok)
802 return;
803
804 /*
805 * We have an ok overlap. We will drop it from the early
806 * reservation map, and add back in any non-overlapping
807 * portions (lower or upper) as separate, overlap_ok,
808 * non-overlapping ranges.
809 */
810
811 /* 1. Note any non-overlapping (lower or upper) ranges. */
812 strncpy(name, r->name, sizeof(name) - 1);
813
814 lower_start = lower_end = 0;
815 upper_start = upper_end = 0;
816 if (r->start < start) {
817 lower_start = r->start;
818 lower_end = start;
819 }
820 if (r->end > end) {
821 upper_start = end;
822 upper_end = r->end;
823 }
824
825 /* 2. Drop the original ok overlapping range */
826 drop_range(i);
827
828 i--; /* resume for-loop on copied down entry */
829
830 /* 3. Add back in any non-overlapping ranges. */
831 if (lower_end)
832 reserve_early_overlap_ok(lower_start, lower_end, name);
833 if (upper_end)
834 reserve_early_overlap_ok(upper_start, upper_end, name);
835 }
836}
837
838static void __init __reserve_early(u64 start, u64 end, char *name,
839 int overlap_ok)
840{
841 int i;
842 struct early_res *r;
843
844 i = find_overlapped_early(start, end);
845 if (i >= MAX_EARLY_RES)
846 panic("Too many early reservations");
847 r = &early_res[i];
848 if (r->end)
849 panic("Overlapping early reservations "
850 "%llx-%llx %s to %llx-%llx %s\n",
851 start, end - 1, name?name:"", r->start,
852 r->end - 1, r->name);
853 r->start = start;
854 r->end = end;
855 r->overlap_ok = overlap_ok;
856 if (name)
857 strncpy(r->name, name, sizeof(r->name) - 1);
858}
859
860/*
861 * A few early reservtations come here.
862 *
863 * The 'overlap_ok' in the name of this routine does -not- mean it
864 * is ok for these reservations to overlap an earlier reservation.
865 * Rather it means that it is ok for subsequent reservations to
866 * overlap this one.
867 *
868 * Use this entry point to reserve early ranges when you are doing
869 * so out of "Paranoia", reserving perhaps more memory than you need,
870 * just in case, and don't mind a subsequent overlapping reservation
871 * that is known to be needed.
872 *
873 * The drop_overlaps_that_are_ok() call here isn't really needed.
874 * It would be needed if we had two colliding 'overlap_ok'
875 * reservations, so that the second such would not panic on the
876 * overlap with the first. We don't have any such as of this
877 * writing, but might as well tolerate such if it happens in
878 * the future.
879 */
880void __init reserve_early_overlap_ok(u64 start, u64 end, char *name)
881{
882 drop_overlaps_that_are_ok(start, end);
883 __reserve_early(start, end, name, 1);
884}
885
886/*
887 * Most early reservations come here.
888 *
889 * We first have drop_overlaps_that_are_ok() drop any pre-existing
890 * 'overlap_ok' ranges, so that we can then reserve this memory
891 * range without risk of panic'ing on an overlapping overlap_ok
892 * early reservation.
893 */
894void __init reserve_early(u64 start, u64 end, char *name)
895{
896 if (start >= end)
897 return;
898
899 drop_overlaps_that_are_ok(start, end);
900 __reserve_early(start, end, name, 0);
901}
902
903void __init free_early(u64 start, u64 end)
904{
905 struct early_res *r;
906 int i;
907
908 i = find_overlapped_early(start, end);
909 r = &early_res[i];
910 if (i >= MAX_EARLY_RES || r->end != end || r->start != start)
911 panic("free_early on not reserved area: %llx-%llx!",
912 start, end - 1);
913
914 drop_range(i);
915}
916 759
917void __init early_res_to_bootmem(u64 start, u64 end) 760 if (addr != -1ULL)
918{ 761 return addr;
919 int i, count;
920 u64 final_start, final_end;
921
922 count = 0;
923 for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++)
924 count++;
925
926 printk(KERN_INFO "(%d early reservations) ==> bootmem [%010llx - %010llx]\n",
927 count, start, end);
928 for (i = 0; i < count; i++) {
929 struct early_res *r = &early_res[i];
930 printk(KERN_INFO " #%d [%010llx - %010llx] %16s", i,
931 r->start, r->end, r->name);
932 final_start = max(start, r->start);
933 final_end = min(end, r->end);
934 if (final_start >= final_end) {
935 printk(KERN_CONT "\n");
936 continue;
937 }
938 printk(KERN_CONT " ==> [%010llx - %010llx]\n",
939 final_start, final_end);
940 reserve_bootmem_generic(final_start, final_end - final_start,
941 BOOTMEM_DEFAULT);
942 } 762 }
763 return -1ULL;
943} 764}
944 765
945/* Check for already reserved areas */ 766u64 __init find_fw_memmap_area(u64 start, u64 end, u64 size, u64 align)
946static inline int __init bad_addr(u64 *addrp, u64 size, u64 align)
947{
948 int i;
949 u64 addr = *addrp;
950 int changed = 0;
951 struct early_res *r;
952again:
953 i = find_overlapped_early(addr, addr + size);
954 r = &early_res[i];
955 if (i < MAX_EARLY_RES && r->end) {
956 *addrp = addr = round_up(r->end, align);
957 changed = 1;
958 goto again;
959 }
960 return changed;
961}
962
963/* Check for already reserved areas */
964static inline int __init bad_addr_size(u64 *addrp, u64 *sizep, u64 align)
965{ 767{
966 int i; 768 return find_e820_area(start, end, size, align);
967 u64 addr = *addrp, last;
968 u64 size = *sizep;
969 int changed = 0;
970again:
971 last = addr + size;
972 for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
973 struct early_res *r = &early_res[i];
974 if (last > r->start && addr < r->start) {
975 size = r->start - addr;
976 changed = 1;
977 goto again;
978 }
979 if (last > r->end && addr < r->end) {
980 addr = round_up(r->end, align);
981 size = last - addr;
982 changed = 1;
983 goto again;
984 }
985 if (last <= r->end && addr >= r->start) {
986 (*sizep)++;
987 return 0;
988 }
989 }
990 if (changed) {
991 *addrp = addr;
992 *sizep = size;
993 }
994 return changed;
995} 769}
996 770
997/* 771u64 __init get_max_mapped(void)
998 * Find a free area with specified alignment in a specific range.
999 */
1000u64 __init find_e820_area(u64 start, u64 end, u64 size, u64 align)
1001{ 772{
1002 int i; 773 u64 end = max_pfn_mapped;
1003 774
1004 for (i = 0; i < e820.nr_map; i++) { 775 end <<= PAGE_SHIFT;
1005 struct e820entry *ei = &e820.map[i];
1006 u64 addr, last;
1007 u64 ei_last;
1008 776
1009 if (ei->type != E820_RAM) 777 return end;
1010 continue;
1011 addr = round_up(ei->addr, align);
1012 ei_last = ei->addr + ei->size;
1013 if (addr < start)
1014 addr = round_up(start, align);
1015 if (addr >= ei_last)
1016 continue;
1017 while (bad_addr(&addr, size, align) && addr+size <= ei_last)
1018 ;
1019 last = addr + size;
1020 if (last > ei_last)
1021 continue;
1022 if (last > end)
1023 continue;
1024 return addr;
1025 }
1026 return -1ULL;
1027} 778}
1028
1029/* 779/*
1030 * Find next free range after *start 780 * Find next free range after *start
1031 */ 781 */
@@ -1035,25 +785,19 @@ u64 __init find_e820_area_size(u64 start, u64 *sizep, u64 align)
1035 785
1036 for (i = 0; i < e820.nr_map; i++) { 786 for (i = 0; i < e820.nr_map; i++) {
1037 struct e820entry *ei = &e820.map[i]; 787 struct e820entry *ei = &e820.map[i];
1038 u64 addr, last; 788 u64 addr;
1039 u64 ei_last; 789 u64 ei_start, ei_last;
1040 790
1041 if (ei->type != E820_RAM) 791 if (ei->type != E820_RAM)
1042 continue; 792 continue;
1043 addr = round_up(ei->addr, align); 793
1044 ei_last = ei->addr + ei->size; 794 ei_last = ei->addr + ei->size;
1045 if (addr < start) 795 ei_start = ei->addr;
1046 addr = round_up(start, align); 796 addr = find_early_area_size(ei_start, ei_last, start,
1047 if (addr >= ei_last) 797 sizep, align);
1048 continue; 798
1049 *sizep = ei_last - addr; 799 if (addr != -1ULL)
1050 while (bad_addr_size(&addr, sizep, align) && 800 return addr;
1051 addr + *sizep <= ei_last)
1052 ;
1053 last = addr + *sizep;
1054 if (last > ei_last)
1055 continue;
1056 return addr;
1057 } 801 }
1058 802
1059 return -1ULL; 803 return -1ULL;
@@ -1412,6 +1156,8 @@ void __init e820_reserve_resources_late(void)
1412 end = MAX_RESOURCE_SIZE; 1156 end = MAX_RESOURCE_SIZE;
1413 if (start >= end) 1157 if (start >= end)
1414 continue; 1158 continue;
1159 printk(KERN_DEBUG "reserve RAM buffer: %016llx - %016llx ",
1160 start, end);
1415 reserve_region_with_split(&iomem_resource, start, end, 1161 reserve_region_with_split(&iomem_resource, start, end,
1416 "RAM buffer"); 1162 "RAM buffer");
1417 } 1163 }