diff --git a/fs/ext4/dev.c b/fs/ext4/dev.c
index 81b7633..2cd182c 100644
--- a/fs/ext4/dev.c
+++ b/fs/ext4/dev.c
@@ -42,7 +42,7 @@
 #include <ext_common.h>
 #include "ext4_common.h"
 
-unsigned long part_offset;
+lbaint_t part_offset;
 
 static block_dev_desc_t *ext4fs_block_dev_desc;
 static disk_partition_t *part_info;
@@ -58,7 +58,7 @@
 		get_fs()->dev_desc->log2blksz;
 }
 
-int ext4fs_devread(int sector, int byte_offset, int byte_len, char *buf)
+int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf)
 {
 	unsigned block_len;
 	int log2blksz = ext4fs_block_dev_desc->log2blksz;
@@ -74,7 +74,8 @@
 	if ((sector < 0) ||
 	    ((sector + ((byte_offset + byte_len - 1) >> log2blksz))
 	     >= part_info->size)) {
-		printf("%s read outside partition %d\n", __func__, sector);
+		printf("%s read outside partition " LBAFU "\n", __func__,
+		       sector);
 		return 0;
 	}
 
@@ -82,7 +83,7 @@
 	sector += byte_offset >> log2blksz;
 	byte_offset &= ext4fs_block_dev_desc->blksz - 1;
 
-	debug(" <%d, %d, %d>\n", sector, byte_offset, byte_len);
+	debug(" <" LBAFU ", %d, %d>\n", sector, byte_offset, byte_len);
 
 	if (byte_offset != 0) {
 		/* read first part which isn't aligned with start of sector */