static u64 get_coherent_dma_mask(struct device *dev)
{
- u64 mask = (u64)arm_dma_limit;
+ u64 mask = (u64)DMA_BIT_MASK(32);
if (dev) {
mask = dev->coherent_dma_mask;
return 0;
}
- if ((~mask) & (u64)arm_dma_limit) {
- dev_warn(dev, "coherent DMA mask %#llx is smaller "
- "than system GFP_DMA mask %#llx\n",
- mask, (u64)arm_dma_limit);
+ /*
+ * If the mask allows for more memory than we can address,
+ * and we actually have that much memory, then fail the
+ * allocation.
+ */
+ if (sizeof(mask) != sizeof(dma_addr_t) &&
+ mask > (dma_addr_t)~0 &&
+ dma_to_pfn(dev, ~0) > arm_dma_pfn_limit) {
+ dev_warn(dev, "Coherent DMA mask %#llx is larger than dma_addr_t allows\n",
+ mask);
+ dev_warn(dev, "Driver did not use or check the return value from dma_set_coherent_mask()?\n");
+ return 0;
+ }
+
+ /*
+ * Now check that the mask, when translated to a PFN,
+ * fits within the allowable addresses which we can
+ * allocate.
+ */
+ if (dma_to_pfn(dev, mask) < arm_dma_pfn_limit) {
+ dev_warn(dev, "Coherent DMA mask %#llx (pfn %#lx-%#lx) covers a smaller range of system memory than the DMA zone pfn 0x0-%#lx\n",
+ mask,
+ dma_to_pfn(dev, 0), dma_to_pfn(dev, mask) + 1,
+ arm_dma_pfn_limit + 1);
return 0;
}
}
*/
int dma_supported(struct device *dev, u64 mask)
{
- if (mask < (u64)arm_dma_limit)
+ unsigned long limit;
+
+ /*
+ * If the mask allows for more memory than we can address,
+ * and we actually have that much memory, then we must
+ * indicate that DMA to this device is not supported.
+ */
+ if (sizeof(mask) != sizeof(dma_addr_t) &&
+ mask > (dma_addr_t)~0 &&
+ dma_to_pfn(dev, ~0) > arm_dma_pfn_limit)
return 0;
+
+ /*
+ * Translate the device's DMA mask to a PFN limit. This
+ * PFN number includes the page which we can DMA to.
+ */
+ limit = dma_to_pfn(dev, mask);
+
+ if (limit < arm_dma_pfn_limit)
+ return 0;
+
return 1;
}
EXPORT_SYMBOL(dma_supported);
break;
len = (j - i) << PAGE_SHIFT;
- ret = iommu_map(mapping->domain, iova, phys, len, 0);
+ ret = iommu_map(mapping->domain, iova, phys, len,
+ IOMMU_READ|IOMMU_WRITE);
if (ret < 0)
goto fail;
iova += len;
GFP_KERNEL);
}
+static int __dma_direction_to_prot(enum dma_data_direction dir)
+{
+ int prot;
+
+ switch (dir) {
+ case DMA_BIDIRECTIONAL:
+ prot = IOMMU_READ | IOMMU_WRITE;
+ break;
+ case DMA_TO_DEVICE:
+ prot = IOMMU_READ;
+ break;
+ case DMA_FROM_DEVICE:
+ prot = IOMMU_WRITE;
+ break;
+ default:
+ prot = 0;
+ }
+
+ return prot;
+}
+
/*
* Map a part of the scatter-gather list into contiguous io address space
*/
int ret = 0;
unsigned int count;
struct scatterlist *s;
+ int prot;
size = PAGE_ALIGN(size);
*handle = DMA_ERROR_CODE;
!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
__dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
- ret = iommu_map(mapping->domain, iova, phys, len, 0);
+ prot = __dma_direction_to_prot(dir);
+
+ ret = iommu_map(mapping->domain, iova, phys, len, prot);
if (ret < 0)
goto fail;
count += len >> PAGE_SHIFT;
if (dma_addr == DMA_ERROR_CODE)
return dma_addr;
- switch (dir) {
- case DMA_BIDIRECTIONAL:
- prot = IOMMU_READ | IOMMU_WRITE;
- break;
- case DMA_TO_DEVICE:
- prot = IOMMU_READ;
- break;
- case DMA_FROM_DEVICE:
- prot = IOMMU_WRITE;
- break;
- default:
- prot = 0;
- }
+ prot = __dma_direction_to_prot(dir);
ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len, prot);
if (ret < 0)