1 files changed, 31 insertions, 0 deletions
diff --git a/usr/umode.c b/usr/umode.c
new file mode 100644
index 0000000..4ef5306
--- /dev/null
+++ b/usr/umode.c
@@ -0,0 +1,31 @@
+#include "umode.h"
+#include "elf.h"
+#include "boot/cmdline.h"
+#include "lib/jove.h"
+#include "ird/initrd.h"
+#include "mem/memory.h"
+
+void
+umode_setup(void)
+{
+    extern void syscall_setup_syscall(void);
+    syscall_setup_syscall();
+
+    const char *init_path = cmdline_get("init");
+    if(init_path == NULL)
+        kpanic("Missing path to init ELF file / binary\n");
+
+    struct InitrdFile *init_file = ird_getfile(init_path);
+    if(init_file == NULL)
+        kpanic("Missing init file %s in initrd\n", init_path);
+
+    void (*entry_point)(void) = elf_load(init_file->data, init_file->size);
+    if(entry_point == NULL)
+        kpanic("Init file %s is incorrectly formatted (want ELF64)\n", init_path);
+
+    void *user_stack = (void*)(0x00007FFFFFFFFFFF);
+    mem_ensure_range((uintptr_t)user_stack & ~0xFFF, (uintptr_t)user_stack, true, true);
+
+    klogf("User entry point %#016X\n", entry_point);
+    umode_enter(entry_point, user_stack);
+}