[PATCH v2] iommu/dma: Rationalise types for DMA masks

From: Robin Murphy
Date: Wed Dec 11 2019 - 13:33:34 EST


Since iommu_dma_alloc_iova() combines incoming masks with the u64 bus
limit, it makes more sense to pass them around in their native u64
rather than converting to dma_addr_t early. Do that, and resolve the
remaining type discrepancy against the domain geometry with a cheeky
cast to keep things simple.

Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---

v2: Reworked from "iommu/dma: Use a better type for dma_limit"

drivers/iommu/dma-iommu.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 0cc702a70a96..6e573d1cb8bf 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -399,7 +399,7 @@ static int dma_info_to_prot(enum dma_data_direction dir, bool coherent,
}

static dma_addr_t iommu_dma_alloc_iova(struct iommu_domain *domain,
- size_t size, dma_addr_t dma_limit, struct device *dev)
+ size_t size, u64 dma_limit, struct device *dev)
{
struct iommu_dma_cookie *cookie = domain->iova_cookie;
struct iova_domain *iovad = &cookie->iovad;
@@ -424,7 +424,7 @@ static dma_addr_t iommu_dma_alloc_iova(struct iommu_domain *domain,
dma_limit = min_not_zero(dma_limit, dev->bus_dma_limit);

if (domain->geometry.force_aperture)
- dma_limit = min(dma_limit, domain->geometry.aperture_end);
+ dma_limit = min(dma_limit, (u64)domain->geometry.aperture_end);

/* Try to get PCI devices a SAC address */
if (dma_limit > DMA_BIT_MASK(32) && dev_is_pci(dev))
@@ -477,7 +477,7 @@ static void __iommu_dma_unmap(struct device *dev, dma_addr_t dma_addr,
}

static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys,
- size_t size, int prot, dma_addr_t dma_mask)
+ size_t size, int prot, u64 dma_mask)
{
struct iommu_domain *domain = iommu_get_dma_domain(dev);
struct iommu_dma_cookie *cookie = domain->iova_cookie;
--
2.23.0.dirty