arch: i386: kernel: add mostly finished PFA and paging system

Add the mostly finished physical memory allocator and expose its
functions to the paging system.

Signed-off-by: Danny Holman <dholman@gymli.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/arch/i386/include/kernel/pmem.h b/arch/i386/include/kernel/pmem.h
new file mode 100644
index 0000000..ddd9c8b
--- /dev/null
+++ b/arch/i386/include/kernel/pmem.h
@@ -0,0 +1,28 @@
+#ifndef I386_PMEM_H
+#define I386_PMEM_H
+
+#include <kernel/multiboot.h>
+#include <stdint.h>
+
+#define PFA_BLOCK_FREE  1
+#define PFA_BLOCK_ALLOC 3
+
+#define PFA_ALLOC_ERR   0xFFFFFFFF
+
+struct pfa_page {
+        struct pfa_page *next;
+};
+
+struct pfa_zone {
+        uintptr_t start;
+        uintptr_t size;
+        struct pfa_page *freelist;
+};
+
+int pfa_init(struct mboot_info *header);
+
+uintptr_t pfa_alloc(void);
+void pfa_free(struct pfa_zone *zone, uintptr_t paddr);
+void pfa_free_range(struct pfa_zone *zone, uintptr_t pstart, uintptr_t pend);
+
+#endif