move most of the memory stuff to kernel/mem/

1 files changed, 38 insertions, 0 deletions

diff --git a/src/kernel/mem/alloc.c b/src/kernel/mem/alloc.c
new file mode 100644
index 0000000..42a2f3b
--- /dev/null
+++ b/src/kernel/mem/alloc.c
@@ -0,0 +1,38 @@
+#include <kernel/arch/generic.h>
+#include <kernel/mem/alloc.h>
+#include <kernel/util.h>
+#include <stdint.h>
+
+static void *highest_page;
+
+void mem_init(struct kmain_info *info) {
+	// finds the highest used page, and starts allocating pages above it
+	void *highest = &_bss_end;
+
+	if (highest < info->init.at + info->init.size)
+		highest = info->init.at + info->init.size;
+
+	// align up to PAGE_SIZE
+	highest_page = (void*)(((uintptr_t)highest + PAGE_MASK) & ~PAGE_MASK);
+}
+
+void *page_alloc(size_t pages) {
+	void *bottom = highest_page;
+	highest_page += pages * PAGE_SIZE;
+	return bottom;
+}
+
+// frees `pages` consecutive pages starting from *first
+void page_free(void *first, size_t pages) {
+	// not implemented
+}
+
+
+void *kmalloc(size_t len) {
+	// extremely inefficient, but this is only temporary anyways
+	return page_alloc(len / PAGE_SIZE + 1);
+}
+
+void kfree(void *ptr) {
+	// unimplemented
+}