[PATCH 18/21] dma-iommu: don't depend on CONFIG_DMA_DIRECT_REMAP

From: Christoph Hellwig
Date: Wed Mar 27 2019 - 04:06:10 EST


For entirely dma coherent architectures there is no requirement to ever
remap dma coherent allocation. Move all the remap and pool code under
CONFIG_DMA_DIRECT_REMAP ifdefs, and drop the Kconfig dependency.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/iommu/Kconfig | 1 -
drivers/iommu/dma-iommu.c | 10 ++++++++++
2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index bdc14baf2ee5..6f07f3b21816 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -95,7 +95,6 @@ config IOMMU_DMA
select IOMMU_API
select IOMMU_IOVA
select NEED_SG_DMA_LENGTH
- depends on DMA_DIRECT_REMAP

config FSL_PAMU
bool "Freescale IOMMU support"
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index f65dd19b0953..092b689c1c54 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -500,6 +500,7 @@ static void *iommu_dma_alloc_contiguous(struct device *dev, size_t size,
return page_address(page);
}

+#ifdef CONFIG_DMA_DIRECT_REMAP
static void __iommu_dma_free_pages(struct page **pages, int count)
{
while (count--)
@@ -782,6 +783,7 @@ static void *iommu_dma_alloc_noncoherent(struct device *dev, size_t size,
gfp, attrs);
return iommu_dma_alloc_remap(dev, size, dma_handle, gfp, attrs);
}
+#endif /* CONFIG_DMA_DIRECT_REMAP */

static void iommu_dma_sync_single_for_cpu(struct device *dev,
dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
@@ -1064,6 +1066,7 @@ static void *iommu_dma_alloc(struct device *dev, size_t size,
*/
gfp |= __GFP_ZERO;

+#ifdef CONFIG_DMA_DIRECT_REMAP
if (!dev_is_dma_coherent(dev))
return iommu_dma_alloc_noncoherent(dev, size, dma_handle, gfp,
attrs);
@@ -1071,6 +1074,7 @@ static void *iommu_dma_alloc(struct device *dev, size_t size,
if (gfpflags_allow_blocking(gfp) &&
!(attrs & DMA_ATTR_FORCE_CONTIGUOUS))
return iommu_dma_alloc_remap(dev, size, dma_handle, gfp, attrs);
+#endif

return iommu_dma_alloc_contiguous(dev, size, dma_handle, gfp, attrs);
}
@@ -1090,6 +1094,7 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr,
*
* Hence how dodgy the below logic looks...
*/
+#ifdef CONFIG_DMA_DIRECT_REMAP
if (dma_in_atomic_pool(cpu_addr, PAGE_ALIGN(size))) {
iommu_dma_free_pool(dev, size, cpu_addr, dma_handle);
return;
@@ -1103,6 +1108,7 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr,
page = vmalloc_to_page(cpu_addr);
dma_common_free_remap(cpu_addr, PAGE_ALIGN(size), VM_USERMAP);
} else
+#endif
page = virt_to_page(cpu_addr);

iommu_dma_free_contiguous(dev, size, page, dma_handle);
@@ -1125,11 +1131,13 @@ static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma,
if (off >= nr_pages || vma_pages(vma) > nr_pages - off)
return -ENXIO;

+#ifdef CONFIG_DMA_DIRECT_REMAP
if (is_vmalloc_addr(cpu_addr)) {
if (!(attrs & DMA_ATTR_FORCE_CONTIGUOUS))
return iommu_dma_mmap_remap(cpu_addr, size, vma);
pfn = vmalloc_to_pfn(cpu_addr);
} else
+#endif
pfn = page_to_pfn(virt_to_page(cpu_addr));

return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
@@ -1143,11 +1151,13 @@ static int iommu_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
struct page *page;
int ret;

+#ifdef CONFIG_DMA_DIRECT_REMAP
if (is_vmalloc_addr(cpu_addr)) {
if (!(attrs & DMA_ATTR_FORCE_CONTIGUOUS))
return iommu_dma_get_sgtable_remap(sgt, cpu_addr, size);
page = vmalloc_to_page(cpu_addr);
} else
+#endif
page = virt_to_page(cpu_addr);

ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
--
2.20.1