diff options
| -rw-r--r-- | arch/x86/kernel/e820.c | 59 |
1 files changed, 24 insertions, 35 deletions
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 303a0e48f076..f655f802260d 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -19,6 +19,7 @@ #include <linux/acpi.h> #include <linux/firmware-map.h> #include <linux/memblock.h> +#include <linux/sort.h> #include <asm/e820.h> #include <asm/proto.h> @@ -227,22 +228,38 @@ void __init e820_print_map(char *who) * ____________________33__ * ______________________4_ */ +struct change_member { + struct e820entry *pbios; /* pointer to original bios entry */ + unsigned long long addr; /* address for this change point */ +}; + +static int __init cpcompare(const void *a, const void *b) +{ + struct change_member * const *app = a, * const *bpp = b; + const struct change_member *ap = *app, *bp = *bpp; + + /* + * Inputs are pointers to two elements of change_point[]. If their + * addresses are unequal, their difference dominates. If the addresses + * are equal, then consider one that represents the end of its region + * to be greater than one that does not. + */ + if (ap->addr != bp->addr) + return ap->addr > bp->addr ? 1 : -1; + + return (ap->addr != ap->pbios->addr) - (bp->addr != bp->pbios->addr); +} int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map, u32 *pnr_map) { - struct change_member { - struct e820entry *pbios; /* pointer to original bios entry */ - unsigned long long addr; /* address for this change point */ - }; static struct change_member change_point_list[2*E820_X_MAX] __initdata; static struct change_member *change_point[2*E820_X_MAX] __initdata; static struct e820entry *overlap_list[E820_X_MAX] __initdata; static struct e820entry new_bios[E820_X_MAX] __initdata; - struct change_member *change_tmp; unsigned long current_type, last_type; unsigned long long last_addr; - int chgidx, still_changing; + int chgidx; int overlap_entries; int new_bios_entry; int old_nr, new_nr, chg_nr; @@ -279,35 +296,7 @@ int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map, chg_nr = chgidx; /* sort change-point list by memory addresses (low -> high) */ - still_changing = 1; - while (still_changing) { - still_changing = 0; - for (i = 1; i < chg_nr; i++) { - unsigned long long curaddr, lastaddr; - unsigned long long curpbaddr, lastpbaddr; - - curaddr = change_point[i]->addr; - lastaddr = change_point[i - 1]->addr; - curpbaddr = change_point[i]->pbios->addr; - lastpbaddr = change_point[i - 1]->pbios->addr; - - /* - * swap entries, when: - * - * curaddr > lastaddr or - * curaddr == lastaddr and curaddr == curpbaddr and - * lastaddr != lastpbaddr - */ - if (curaddr < lastaddr || - (curaddr == lastaddr && curaddr == curpbaddr && - lastaddr != lastpbaddr)) { - change_tmp = change_point[i]; - change_point[i] = change_point[i-1]; - change_point[i-1] = change_tmp; - still_changing = 1; - } - } - } + sort(change_point, chg_nr, sizeof *change_point, cpcompare, 0); /* create a new bios memory map, removing overlaps */ overlap_entries = 0; /* number of entries in the overlap table */ |