uio: fix dmem_region_start computation

commit 4d31a2588ae37a5d0f61f4d956454e9504846aeb upstream.

The variable i contains a total number of resources (including
IORESOURCE_IRQ). However, we want the dmem_region_start to point
after the last resource of type IORESOURCE_MEM. The original behaviour
leads (very likely) to skipping several UIO mapping regions and makes
them useless. Fix this by computing dmem_region_start from the uiomem
which points to the last used UIO mapping.

Fixes: 0a0c3b5a24bd ("Add new uio device for dynamic memory allocation")
Signed-off-by: Jan Viktorin <viktorin@rehivetech.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/drivers/uio/uio_dmem_genirq.c b/drivers/uio/uio_dmem_genirq.c
index 1270f3b2613949626463492e8046f0d1db1b9f20..9d6a9105d83fbf6d55a9ed0bc69fa10e7d9d4d72 100644 (file)
--- a/drivers/uio/uio_dmem_genirq.c
+++ b/drivers/uio/uio_dmem_genirq.c
@@ -229,7 +229,7 @@ static int uio_dmem_genirq_probe(struct platform_device *pdev)
                ++uiomem;
        }
 
-       priv->dmem_region_start = i;
+       priv->dmem_region_start = uiomem - &uioinfo->mem[0];
        priv->num_dmem_regions = pdata->num_dynamic_regions;
 
        for (i = 0; i < pdata->num_dynamic_regions; ++i) {