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arm64: dma-mapping: Fix dma_mapping_error() when bypassing SWIOTLB 

When bypassing SWIOTLB on small-memory systems, we need to avoid calling
into swiotlb_dma_mapping_error() in exactly the same way as we avoid
swiotlb_dma_supported(), because the former also relies on SWIOTLB state
being initialised.

Under the assumptions for which we skip SWIOTLB, dma_map_{single,page}()
will only ever return the DMA-offset-adjusted physical address of the
page passed in, thus we can report success unconditionally.

Fixes: b67a8b29df ("arm64: mm: only initialize swiotlb when necessary")
CC: stable@vger.kernel.org
CC: Jisheng Zhang <jszhang@marvell.com>
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
hifive-unleashed-5.1
Robin Murphy 2017-01-25 18:31:31 +00:00 committed by Will Deacon
parent 2e449048a2
commit adbe7e26f4
1 changed files with 8 additions and 1 deletions
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9
arch/arm64/mm/dma-mapping.c
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@ -356,6 +356,13 @@ static int __swiotlb_dma_supported(struct device *hwdev, u64 mask)
return 1;
}
static int __swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t addr)
{
if (swiotlb)
return swiotlb_dma_mapping_error(hwdev, addr);
return 0;
}
static struct dma_map_ops swiotlb_dma_ops = {
.alloc = __dma_alloc,
.free = __dma_free,
@ -370,7 +377,7 @@ static struct dma_map_ops swiotlb_dma_ops = {
.sync_sg_for_cpu = __swiotlb_sync_sg_for_cpu,
.sync_sg_for_device = __swiotlb_sync_sg_for_device,
.dma_supported = __swiotlb_dma_supported,
.mapping_error = swiotlb_dma_mapping_error,
.mapping_error = __swiotlb_dma_mapping_error,
};
static int __init atomic_pool_init(void)