Add module "memory"

arch/Makefile

@@ -5,6 +5,7 @@ CC = $(CCPREFIX)gcc
 OBJS = start.s.o
 OBJS += init.c.o
 OBJS += multiboot.c.o
+OBJS += memory.c.o
 OBJS += paging.c.o paging.asm.cpp.o
 
 # Architecture-independent

arch/memory.c

@@ -0,0 +1,54 @@
+#include "memory.h"
+
+#include "config.h"
+
+#include <kernelmq/stdlib.h>
+
+#define FRAMES_COUNT (PAGE_DIR_SIZE * PAGE_TABLE_SIZE) // / sizeof(unsigned char))
+
+static unsigned char frames[FRAMES_COUNT];
+
+static void mark_used(unsigned long base, unsigned long limit);
+
+void memory_initialize(const struct KernelMQ_Info *const kinfo)
+{
+    kmemset(frames, 0, sizeof(frames));
+
+    mark_used(kinfo->kernel_phys_base, kinfo->kernel_phys_limit);
+
+    for (unsigned int i = 0; i < kinfo->modules_count; ++i) {
+        const struct KernelMQ_Info_Module *const module = &kinfo->modules[i];
+
+        mark_used(module->base, module->limit);
+    }
+
+    for (unsigned int i = 0; i < kinfo->areas_count; ++i) {
+        const struct KernelMQ_Info_Area *const area = &kinfo->areas[i];
+
+        if (!area->is_available) {
+            mark_used(area->base, area->limit);
+        }
+    }
+}
+
+unsigned long memory_alloc_page()
+{
+    for (unsigned int i = 0; i < FRAMES_COUNT; ++i) {
+        if (!frames[i]) {
+            return i * PAGE_SIZE;
+        }
+    }
+
+    return 0;
+}
+
+void mark_used(const unsigned long base, const unsigned long limit)
+{
+    const unsigned int start = base / PAGE_SIZE;
+
+    const unsigned int end = limit % PAGE_SIZE ? limit / PAGE_SIZE : limit / PAGE_SIZE + 1;
+
+    for (unsigned int i = start; i <= end; ++i) {
+        frames[i] = 1;
+    }
+}

arch/memory.h

@@ -0,0 +1,9 @@
+#ifndef KERNELMQ_INCLUDED_MEMORY
+#define KERNELMQ_INCLUDED_MEMORY 1
+
+#include <kernelmq/info.h>
+
+void memory_initialize(const struct KernelMQ_Info *kinfo);
+unsigned long memory_alloc_page();
+
+#endif