Merge branch 'devel'

[palacios.git] / kitten / arch / x86_64 / mm / phys_addr.c

diff --git a/kitten/arch/x86_64/mm/phys_addr.c b/kitten/arch/x86_64/mm/phys_addr.c
new file mode 100644 (file)
index 0000000..90e6097
--- /dev/null
+++ b/kitten/arch/x86_64/mm/phys_addr.c
@@ -0,0 +1,21 @@
+#include <arch/page.h>
+
+extern unsigned long phys_base;
+
+/**
+ * This converts a kernel virtual address to a physical address.
+ *
+ * NOTE: This function only works for kernel virtual addresses in the kernel's
+ *       identity mapping of all of physical memory. It will not work for the
+ *       fixmap, vmalloc() areas, or any other type of virtual address.
+ */
+unsigned long
+__phys_addr(unsigned long virt_addr)
+{
+       /* Handle kernel symbols */
+       if (virt_addr >= __START_KERNEL_map)
+               return virt_addr - __START_KERNEL_map + phys_base;
+       /* Handle kernel data */
+       return virt_addr - PAGE_OFFSET;
+}
+