diff --git a/ports-foc/include/genode/block.h b/ports-foc/include/genode/block.h
index 60b1cf05b..49effd29d 100644
--- a/ports-foc/include/genode/block.h
+++ b/ports-foc/include/genode/block.h
@@ -40,7 +40,7 @@ L4_CV void* genode_block_request(unsigned idx, unsigned long sz,
                                  void *req, unsigned long *offset);
 
 L4_CV void genode_block_submit(unsigned idx, unsigned long queue_offset,
-                               unsigned long size, unsigned long disc_offset,
+                               unsigned long size, unsigned long long disc_offset,
                                int write);
 
 L4_CV void genode_block_collect_responses(unsigned idx);
diff --git a/ports-foc/src/drivers/genode_block.c b/ports-foc/src/drivers/genode_block.c
index 1d74a0d87..707475680 100644
--- a/ports-foc/src/drivers/genode_block.c
+++ b/ports-foc/src/drivers/genode_block.c
@@ -62,7 +62,7 @@ static void genode_blk_request(struct request_queue *q)
 	struct request *req;
 	unsigned long  queue_offset;
 	void          *buf;
-	unsigned long  offset;
+	unsigned long long  offset;
 	unsigned long  nbytes;
 	short          write;
 	struct genode_blk_device* dev;
@@ -155,7 +155,7 @@ static int genode_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 	struct genode_blk_device *dev  = bdev->bd_disk->private_data;
 	unsigned long             size = dev->blk_cnt * dev->blk_sz *
 	                                 (dev->blk_sz / KERNEL_SECTOR_SIZE);
-	geo->cylinders = size << 5;
+	geo->cylinders = size >> 7;
 	geo->heads     = 4;
 	geo->sectors   = 32;
 	return 0;
diff --git a/ports-foc/src/lib/l4lx/genode_block.cc b/ports-foc/src/lib/l4lx/genode_block.cc
index 6dea14192..edb2a9b86 100644
--- a/ports-foc/src/lib/l4lx/genode_block.cc
+++ b/ports-foc/src/lib/l4lx/genode_block.cc
@@ -295,7 +295,7 @@ extern "C" {
 
 
 	void genode_block_submit(unsigned idx, unsigned long queue_offset,
-	                         unsigned long size, unsigned long disc_offset, int write)
+	                         unsigned long size, unsigned long long disc_offset, int write)
 	{
 		if (idx >= genode_block_count()) {
 			PWRN("Invalid index!");