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Commit 65b050ad authored by Joerg Roedel's avatar Joerg Roedel Committed by Ingo Molnar
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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: default avatarJoerg 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: default avatarIngo Molnar <mingo@elte.hu>
parent 4da70b9e

arch/x86/kernel/amd_iommu.c

+98 −0
Original line number Diff line number Diff line
@@ -700,3 +700,101 @@ static void unmap_single(struct device *dev, dma_addr_t dma_addr, 
	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);

}