[PATCH 3.16.y-ckt 020/126] ARM: 8427/1: dma-mapping: add support for offset parameter in dma_mmap()

[Luis Henriques]

3.16.7-ckt21 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Marek Szyprowski <m.szyprowski at samsung.com>

commit 7e31210349e9e03a9a4dff31ab5f2bc83e8e84f5 upstream.

IOMMU-based dma_mmap() implementation lacked proper support for offset
parameter used in mmap call (it always assumed that mapping starts from
offset zero). This patch adds support for offset parameter to IOMMU-based
implementation.

Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 arch/arm/mm/dma-mapping.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 59336561d747..832b295eb4a5 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1470,6 +1470,8 @@ static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 	if (off >= nr_pages || (usize >> PAGE_SHIFT) > nr_pages - off)
 		return -ENXIO;
 
+	pages += off;
+
 	do {
 		int ret = vm_insert_page(vma, uaddr, *pages++);
 		if (ret) {