PoliEcho/kern
1
0
Fork 0
forked from PoliEcho-holding-org/kern
Code Pull Requests Activity

Added basic paging.h & paging.c

Browse Source
This commit is contained in:
Tom-on
2025-03-28 11:30:43 +01:00
parent f73a6f9ccb
commit 5cee647ff0
6 changed files with 93 additions and 36 deletions
Download Patch File Download Diff File Expand all files Collapse all files
kernel/src/pmm.c
+17 -12
View File
@@ -1,22 +1,27 @@
#include <multiboot.h>
#include <bootloader.h>
#include <kernel.h>
#include <string.h>
#include <pmm.h>
// Helpers
#define SET_BLOCK(_b) memmap[(_b) / 32] |= (1 << ((_b) % 32))
#define USET_BLOCK(_b) memmap[(_b) / 32] &= ~(1 << ((_b) % 32))
#define TEST_BLOCK(_b) ((memmap[(_b) % 32] & (1 << ((_b) % 32))) ? 1 : 0)
// Bitmap & helpers
uint32_t* bitmap = NULL;
#define SET_BLOCK(_b) bitmap[(_b) / 32] |= (1 << ((_b) % 32))
#define USET_BLOCK(_b) bitmap[(_b) / 32] &= ~(1 << ((_b) % 32))
#define TEST_BLOCK(_b) ((bitmap[(_b) % 32] & (1 << ((_b) % 32))) ? 1 : 0)
// Memory manager bitmap
uint32_t* memmap = NULL;
// Status
size_t usedBlocks = 0;
size_t maxBlocks = 0;
// TODO: improve these hardcoded values
int pmm_init(void) {
memmap = NULL; // Memory map location
usedBlocks = 0;
maxBlocks = 0; // TODO
size_t totalmem = (bootloader.memLower + bootloader.memUpper) * 1024;
maxBlocks = totalmem / PMM_BS;
usedBlocks = maxBlocks;
// TODO:
bitmap = (uint32_t*)NULL;
memset(bitmap, 0, maxBlocks / PMM_BPB);
return 0;
}
@@ -27,7 +32,7 @@ int findFreeBlocks(size_t blockCount) {
uint32_t freeCount = 0;
for (size_t i = 0; i < max; i++) {
// We don't have to check, cause it's all reserved
if (memmap[i] == 0xffffffff) continue;
if (bitmap[i] == 0xffffffff) continue;
for (uint8_t j = 0; j < 32; j++) {
if (TEST_BLOCK(i * PMM_BPB + j)) freeCount++;