x86, AMD IOMMU: add mapping functions for scatter gather lists
This patch adds the dma_ops functions for mapping and unmapping scatter gather
lists.
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 b4079f6..f4747fe 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -700,3 +700,101 @@
spin_unlock_irqrestore(&domain->lock, flags);
}
+static int map_sg_no_iommu(struct device *dev, struct scatterlist *sglist,
+ int nelems, int dir)
+{
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sglist, s, nelems, i) {
+ s->dma_address = (dma_addr_t)sg_phys(s);
+ s->dma_length = s->length;
+ }
+
+ return nelems;
+}
+
+static int map_sg(struct device *dev, struct scatterlist *sglist,
+ int nelems, int dir)
+{
+ unsigned long flags;
+ struct amd_iommu *iommu;
+ struct protection_domain *domain;
+ u16 devid;
+ int i;
+ struct scatterlist *s;
+ phys_addr_t paddr;
+ int mapped_elems = 0;
+
+ get_device_resources(dev, &iommu, &domain, &devid);
+
+ if (!iommu || !domain)
+ return map_sg_no_iommu(dev, sglist, nelems, dir);
+
+ spin_lock_irqsave(&domain->lock, flags);
+
+ for_each_sg(sglist, s, nelems, i) {
+ paddr = sg_phys(s);
+
+ s->dma_address = __map_single(dev, iommu, domain->priv,
+ paddr, s->length, dir);
+
+ if (s->dma_address) {
+ s->dma_length = s->length;
+ mapped_elems++;
+ } else
+ goto unmap;
+ if (iommu_has_npcache(iommu))
+ iommu_flush_pages(iommu, domain->id, s->dma_address,
+ s->dma_length);
+ }
+
+ if (iommu->need_sync)
+ iommu_completion_wait(iommu);
+
+out:
+ spin_unlock_irqrestore(&domain->lock, flags);
+
+ return mapped_elems;
+unmap:
+ for_each_sg(sglist, s, mapped_elems, i) {
+ if (s->dma_address)
+ __unmap_single(iommu, domain->priv, s->dma_address,
+ s->dma_length, dir);
+ s->dma_address = s->dma_length = 0;
+ }
+
+ mapped_elems = 0;
+
+ goto out;
+}
+
+static void unmap_sg(struct device *dev, struct scatterlist *sglist,
+ int nelems, int dir)
+{
+ unsigned long flags;
+ struct amd_iommu *iommu;
+ struct protection_domain *domain;
+ struct scatterlist *s;
+ u16 devid;
+ int i;
+
+ if (!get_device_resources(dev, &iommu, &domain, &devid))
+ return;
+
+ spin_lock_irqsave(&domain->lock, flags);
+
+ for_each_sg(sglist, s, nelems, i) {
+ __unmap_single(iommu, domain->priv, s->dma_address,
+ s->dma_length, dir);
+ iommu_flush_pages(iommu, domain->id, s->dma_address,
+ s->dma_length);
+ s->dma_address = s->dma_length = 0;
+ }
+
+ if (iommu->need_sync)
+ iommu_completion_wait(iommu);
+
+ spin_unlock_irqrestore(&domain->lock, flags);
+}
+