implements first free mem block

kernel/arch/pmm/pmm.c

@@ -1,3 +1,6 @@
+#include <stdint.h>
+
+#include <kernel/_kernel.h>
 #include <kernel/pmm.h>
 
 /**
@@ -37,11 +40,19 @@ void __pmm_unset(int bit, uint32_t* bitmap)
 	bitmap[bit / 32] &= ~(1 << (bit % 32));
 }
 
-void __pmm_first_free(struct pmm_mem_info mem_block)
+int __pmm_first_free(struct pmm_mem_info mem_block)
 {
 	for (uint32_t i = 0; i < PMM_GET_MEM_BLOCKS(mem_block) / 32; i++) {
-
+		if (mem_block.bitmap[i] == 0xFFFFFFFF) // this segment is full
+			continue;
+		for (int j = 0; j < 32; j++) {
+			if (mem_block.bitmap[i] & (1 << j))
+				continue; // this page is used 
+			return (i * 32) + j; // i * 32 is the chunk of 32, plus j to get to the page in the chunk
+		}
 	}
+	kwarn("OUT OF MEMORY");
+	return -1;
 }
 
 void pmm_set(int bit)

kernel/include/kernel/pmm.h

@@ -1,20 +1,4 @@
-#include <stdbool.h>
-#include <stdint.h>
-#include <stddef.h>
-
 #ifndef ARCH_PMM_H
 #define ARCH_PMM_H
 
-#define PMM_BLOCKS_PER_BYTE 8 // This is for the Bitmap
-#define PMM_BLOCK_SIZE 4096 // 4KiB
-#define PMM_BLOCK_ALIGN (PMM_BLOCK_SIZE) // must be aligned at 4KiB
-
-void set_grub_mem_map(uint32_t addr, uint32_t len);
-uint32_t pmm_get_block_count(void);
-
-int pmm_first_free(void);
-int pmm_first_free_s(size_t pages);
-
-void pmm_init(size_t mem_size, uint32_t* bitmap);
-
 #endif

kernel/kmain.c

@@ -38,14 +38,7 @@ void verify_memmap(multiboot_info_t* mbd, uint32_t magic)
 		// mmmt-> len is in bytes (according to multiboot specification0
 		// mmmt->len / 1024 == kib // block size == blocks
 
-		if (mmmt->type == MULTIBOOT_MEMORY_AVAILABLE && (mmmt->addr == 0x100000)) {
-			// This is the main mem address we want
-			// TODO: this is probably flaky, so i want to find a better and more reliable way to do this
-			set_grub_mem_map(mmmt->addr, mmmt->len);		
-		}
 	}
-
-	printf("%2 %2\n", mbd->mem_lower, mbd->mem_upper);
 }
 
 void _main(multiboot_info_t* mbd, uint32_t magic)
@@ -54,8 +47,6 @@ void _main(multiboot_info_t* mbd, uint32_t magic)
 	terminal_initialize();
 	serial_initialize();
 #endif
-	printf("%2, %2\n", mbd->mem_lower, mbd->mem_upper);
-
 	verify_memmap(mbd, magic);	
 
 	gdt_init();