Properly implement liballoc_free ()

kernel/proc/mem.c

@@ -0,0 +1,17 @@
+#include <libk/std.h>
+#include <proc/mem.h>
+#include <proc/proc.h>
+#include <proc/resource.h>
+#include <sync/spin_lock.h>
+
+void proc_mem_unref (struct proc* proc, struct proc_resource_mem* mem, size_t pages) {
+  spin_lock_ctx_t ctxrs;
+
+  spin_lock (&mem->resource->lock, &ctxrs);
+  mem->alive_pages -= pages;
+  ptrdiff_t current_pages = mem->alive_pages;
+  spin_unlock (&mem->resource->lock, &ctxrs);
+
+  if (current_pages <= 0)
+    proc_drop_resource (proc, mem->resource);
+}