x86, AMD IOMMU: add mapping functions for coherent mappings

This patch adds the dma_ops functions for coherent mappings.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: Sebastian.Biemueller@amd.com
Cc: robert.richter@amd.com
Cc: joro@8bytes.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index f4747fe..aab9125 100644 (file)
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -798,3 +798,77 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist,
        spin_unlock_irqrestore(&domain->lock, flags);
 }
 
+static void *alloc_coherent(struct device *dev, size_t size,
+                           dma_addr_t *dma_addr, gfp_t flag)
+{
+       unsigned long flags;
+       void *virt_addr;
+       struct amd_iommu *iommu;
+       struct protection_domain *domain;
+       u16 devid;
+       phys_addr_t paddr;
+
+       virt_addr = (void *)__get_free_pages(flag, get_order(size));
+       if (!virt_addr)
+               return 0;
+
+       memset(virt_addr, 0, size);
+       paddr = virt_to_phys(virt_addr);
+
+       get_device_resources(dev, &iommu, &domain, &devid);
+
+       if (!iommu || !domain) {
+               *dma_addr = (dma_addr_t)paddr;
+               return virt_addr;
+       }
+
+       spin_lock_irqsave(&domain->lock, flags);
+
+       *dma_addr = __map_single(dev, iommu, domain->priv, paddr,
+                                size, DMA_BIDIRECTIONAL);
+
+       if (*dma_addr == bad_dma_address) {
+               free_pages((unsigned long)virt_addr, get_order(size));
+               virt_addr = NULL;
+               goto out;
+       }
+
+       if (iommu_has_npcache(iommu))
+               iommu_flush_pages(iommu, domain->id, *dma_addr, size);
+
+       if (iommu->need_sync)
+               iommu_completion_wait(iommu);
+
+out:
+       spin_unlock_irqrestore(&domain->lock, flags);
+
+       return virt_addr;
+}
+
+static void free_coherent(struct device *dev, size_t size,
+                         void *virt_addr, dma_addr_t dma_addr)
+{
+       unsigned long flags;
+       struct amd_iommu *iommu;
+       struct protection_domain *domain;
+       u16 devid;
+
+       get_device_resources(dev, &iommu, &domain, &devid);
+
+       if (!iommu || !domain)
+               goto free_mem;
+
+       spin_lock_irqsave(&domain->lock, flags);
+
+       __unmap_single(iommu, domain->priv, dma_addr, size, DMA_BIDIRECTIONAL);
+       iommu_flush_pages(iommu, domain->id, dma_addr, size);
+
+       if (iommu->need_sync)
+               iommu_completion_wait(iommu);
+
+       spin_unlock_irqrestore(&domain->lock, flags);
+
+free_mem:
+       free_pages((unsigned long)virt_addr, get_order(size));
+}
+