Allow external code to update hidden memory regions.

1 files changed, 45 insertions, 0 deletions

diff --git a/src/include/gpxe/hidemem.h b/src/include/gpxe/hidemem.h
new file mode 100644
index 000000000..89109004c
--- /dev/null
+++ b/src/include/gpxe/hidemem.h
@@ -0,0 +1,45 @@
+#ifndef _GPXE_HIDEMEM_H
+#define _GPXE_HIDEMEM_H
+
+/**
+ * @file
+ *
+ * Hidden memory regions
+ *
+ */
+
+/**
+ * A hidden region of Etherboot
+ *
+ * This represents a region that will be edited out of the system's
+ * memory map.
+ *
+ * This structure is accessed by assembly code, so must not be
+ * changed.
+ */
+struct hidden_region {
+	/* Physical start address */
+	physaddr_t start;
+	/* Physical end address */
+	physaddr_t end;
+};
+
+/**
+ * Unique IDs for hidden regions
+ */
+enum {
+	TEXT = 0,
+	BASEMEM,
+	EXTMEM,
+};
+
+extern struct hidden_region __data16_array ( hidden_regions, [] );
+#define hidden_regions __use_data16 ( hidden_regions )
+
+static inline void hide_region ( unsigned int region,
+				 physaddr_t start, physaddr_t end ) {
+	hidden_regions[region].start = start;
+	hidden_regions[region].end = end;
+}
+
+#endif /* _GPXE_HIDEMEM_H */