memscan: build a linked list of memory scanners

By registering memory scanners at runtime we can support multiple memory
scanner functions, which helps us to isolate them and keep things
modular, only registering them for specific platform/derivative
combinations. This is preparation for adding a memory scanner that is
specific to PXELINUX on bios and understands when the memory region
occupied by the PXE stack can be reused.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>

2 files changed, 11 insertions, 4 deletions

diff --git a/com32/include/syslinux/firmware.h b/com32/include/syslinux/firmware.h
index 4a43c86d..6cc06a08 100644
--- a/com32/include/syslinux/firmware.h
+++ b/com32/include/syslinux/firmware.h
@@ -1,7 +1,8 @@
 #ifndef _SYSLINUX_FIRMWARE_H
 #define _SYSLINUX_FIRMWARE_H
 
-#include <syslinux/memscan.h>
+#include <inttypes.h>
+#include <stdbool.h>
 
 struct term_state;
 
@@ -42,7 +43,6 @@ struct mem_ops {
 	void *(*malloc)(size_t, enum heap, size_t);
 	void *(*realloc)(void *, size_t);
 	void (*free)(void *);
-	int (*scan_memory)(scan_memory_callback_t, void *);
 };
 
 struct initramfs;
diff --git a/com32/include/syslinux/memscan.h b/com32/include/syslinux/memscan.h
index 7aabacba..ab78e28b 100644
--- a/com32/include/syslinux/memscan.h
+++ b/com32/include/syslinux/memscan.h
@@ -29,12 +29,19 @@
 #ifndef _SYSLINUX_MEMSCAN_H
 #define _SYSLINUX_MEMSCAN_H
 
-#include <stdbool.h>
+#include <linux/list.h>
 #include <syslinux/movebits.h>	/* addr_t */
 
 typedef int (*scan_memory_callback_t) (void *, addr_t, addr_t,
 				       enum syslinux_memmap_types type);
+
+struct syslinux_memscan {
+    int (*func)(scan_memory_callback_t callback, void *data);
+    struct list_head next;
+};
+
+void syslinux_memscan_add(struct syslinux_memscan *entry);
+int syslinux_memscan_new(int (*func)(scan_memory_callback_t cb, void *data));
 int syslinux_scan_memory(scan_memory_callback_t callback, void *data);
-int bios_scan_memory(scan_memory_callback_t callback, void *data);
 
 #endif /* _SYSLINUX_MEMSCAN_H */