Revert "pmm: Fix issue with get_memmap() that could cause page table corruption"

This reverts commit 9c180b4008.
This commit is contained in:
mintsuki 2022-07-26 20:01:48 +02:00
parent fb5d903ccf
commit 0a2c2896b7

View File

@ -2,7 +2,6 @@
#include <stdint.h>
#include <stdbool.h>
#include <mm/pmm.h>
#include <mm/vmm.h>
#include <sys/e820.h>
#include <lib/acpi.h>
#include <lib/blib.h>
@ -250,52 +249,6 @@ static void pmm_reclaim_uefi_mem(struct e820_entry_t *m, size_t *_count);
struct e820_entry_t *get_memmap(size_t *entries) {
#if uefi == 1
#if defined (__x86_64__)
pagemap_t pagemap = new_pagemap(4);
for (uint64_t i = 0; i < 0x100000000; i += 0x40000000) {
map_page(pagemap, i, i, 0x03, Size1GiB);
}
size_t _memmap_entries = memmap_entries;
struct e820_entry_t *_memmap =
ext_mem_alloc(_memmap_entries * sizeof(struct e820_entry_t));
for (size_t i = 0; i < _memmap_entries; i++)
_memmap[i] = memmap[i];
// Map any other region of memory from the memmap
for (size_t i = 0; i < _memmap_entries; i++) {
uint64_t base = _memmap[i].base;
uint64_t length = _memmap[i].length;
uint64_t top = base + length;
if (base < 0x100000000)
base = 0x100000000;
if (base >= top)
continue;
uint64_t aligned_base = ALIGN_DOWN(base, 0x40000000);
uint64_t aligned_top = ALIGN_UP(top, 0x40000000);
uint64_t aligned_length = aligned_top - aligned_base;
for (uint64_t j = 0; j < aligned_length; j += 0x40000000) {
uint64_t page = aligned_base + j;
map_page(pagemap, page, page, 0x03, Size1GiB);
}
}
asm volatile ("mov %0, %%cr3" :: "r"(pagemap.top_level) : "memory");
#elif defined (__i386__)
asm volatile (
"mov %%cr0, %%eax\n\t"
"btr $31, %%eax\n\t"
"mov %%eax, %%cr0\n\t"
::: "eax", "memory"
);
#endif
pmm_reclaim_uefi_mem(memmap, &memmap_entries);
#endif
sanitise_entries(memmap, &memmap_entries, true);