iommu/intel-iommu: Enable CONFIG_DMA_DIRECT_OPS=y and clean up intel_{alloc,free...

Use the dma_direct_*() helpers and clean up the code flow.

Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Muli Ben-Yehuda <mulix@mulix.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: iommu@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/20180319103826.12853-9-hch@lst.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index dc7c191..df171cb 100644 (file)
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -143,6 +143,7 @@ config DMAR_TABLE
 config INTEL_IOMMU
        bool "Support for Intel IOMMU using DMA Remapping Devices"
        depends on PCI_MSI && ACPI && (X86 || IA64_GENERIC)
+       select DMA_DIRECT_OPS
        select IOMMU_API
        select IOMMU_IOVA
        select DMAR_TABLE

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index fd899b2..24d1b1b 100644 (file)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -31,6 +31,7 @@
 #include <linux/pci.h>
 #include <linux/dmar.h>
 #include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
 #include <linux/mempool.h>
 #include <linux/memory.h>
 #include <linux/cpu.h>
@@ -3708,61 +3709,30 @@ static void *intel_alloc_coherent(struct device *dev, size_t size,
                                  dma_addr_t *dma_handle, gfp_t flags,
                                  unsigned long attrs)
 {
-       struct page *page = NULL;
-       int order;
-
-       size = PAGE_ALIGN(size);
-       order = get_order(size);
-
-       if (!iommu_no_mapping(dev))
-               flags &= ~(GFP_DMA | GFP_DMA32);
-       else if (dev->coherent_dma_mask < dma_get_required_mask(dev)) {
-               if (dev->coherent_dma_mask < DMA_BIT_MASK(32))
-                       flags |= GFP_DMA;
-               else
-                       flags |= GFP_DMA32;
-       }
+       void *vaddr;
 
-       if (gfpflags_allow_blocking(flags)) {
-               unsigned int count = size >> PAGE_SHIFT;
+       vaddr = dma_direct_alloc(dev, size, dma_handle, flags, attrs);
+       if (iommu_no_mapping(dev) || !vaddr)
+               return vaddr;
 
-               page = dma_alloc_from_contiguous(dev, count, order, flags);
-               if (page && iommu_no_mapping(dev) &&
-                   page_to_phys(page) + size > dev->coherent_dma_mask) {
-                       dma_release_from_contiguous(dev, page, count);
-                       page = NULL;
-               }
-       }
-
-       if (!page)
-               page = alloc_pages(flags, order);
-       if (!page)
-               return NULL;
-       memset(page_address(page), 0, size);
-
-       *dma_handle = __intel_map_single(dev, page_to_phys(page), size,
-                                        DMA_BIDIRECTIONAL,
-                                        dev->coherent_dma_mask);
-       if (*dma_handle)
-               return page_address(page);
-       if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
-               __free_pages(page, order);
+       *dma_handle = __intel_map_single(dev, virt_to_phys(vaddr),
+                       PAGE_ALIGN(size), DMA_BIDIRECTIONAL,
+                       dev->coherent_dma_mask);
+       if (!*dma_handle)
+               goto out_free_pages;
+       return vaddr;
 
+out_free_pages:
+       dma_direct_free(dev, size, vaddr, *dma_handle, attrs);
        return NULL;
 }
 
 static void intel_free_coherent(struct device *dev, size_t size, void *vaddr,
                                dma_addr_t dma_handle, unsigned long attrs)
 {
-       int order;
-       struct page *page = virt_to_page(vaddr);
-
-       size = PAGE_ALIGN(size);
-       order = get_order(size);
-
-       intel_unmap(dev, dma_handle, size);
-       if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
-               __free_pages(page, order);
+       if (!iommu_no_mapping(dev))
+               intel_unmap(dev, dma_handle, PAGE_ALIGN(size));
+       dma_direct_free(dev, size, vaddr, dma_handle, attrs);
 }
 
 static void intel_unmap_sg(struct device *dev, struct scatterlist *sglist,