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

From: Robin Murphy <robin.murphy@arm.com>
To: joro@8bytes.org, hch@lst.de
Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
	stephan@gerhold.net, natechancellor@gmail.com,
	nsaenzjulienne@suse.de, arnd@arndb.de
Subject: [PATCH v2] iommu/dma: Rationalise types for DMA masks
Date: Wed, 11 Dec 2019 18:33:26 +0000	[thread overview]
Message-ID: <00d1ddf9439a8c79fb561b0fc740bddf9e6fe6b1.1576089015.git.robin.murphy@arm.com> (raw)

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@arm.com>
---

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

