renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-16 01:04:08 +08:00
Code

iommu/dma: Use correct offset in map_sg

Browse Source 
When mapping a non-page-aligned scatterlist entry, we copy the original
offset to the output DMA address before aligning it to hand off to
iommu_map_sg(), then later adding the IOVA page address portion to get
the final mapped address. However, when the IOVA page size is smaller
than the CPU page size, it is the offset within the IOVA page we want,
not that within the CPU page, which can easily be larger than an IOVA
page and thus result in an incorrect final address.

Fix the bug by taking only the IOVA-aligned part of the offset as the
basis of the DMA address, not the whole thing.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Robin Murphy 2016-01-04 16:19:42 +00:00 committed by Joerg Roedel
parent f64232eee6
commit 164afb1d85
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/iommu/dma-iommu.c
View File

@ -458,7 +458,7 @@ int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg,
size_t s_offset = iova_offset(iovad, s->offset);
size_t s_length = s->length;
sg_dma_address(s) = s->offset;
sg_dma_address(s) = s_offset;
sg_dma_len(s) = s_length;
s->offset -= s_offset;
s_length = iova_align(iovad, s_length + s_offset);