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Commit 06d60728 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Joerg Roedel
Browse files

iommu/dma: move the arm64 wrappers to common code 



There is nothing really arm64 specific in the iommu_dma_ops
implementation, so move it to dma-iommu.c and keep a lot of symbols
self-contained.  Note the implementation does depend on the
DMA_DIRECT_REMAP infrastructure for now, so we'll have to make the
DMA_IOMMU support depend on it, but this will be relaxed soon.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarRobin Murphy <robin.murphy@arm.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 23f88e0a

arch/arm64/mm/dma-mapping.c

+4 −390
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ 
#include <linux/dma-direct.h>

#include <linux/dma-noncoherent.h>

#include <linux/dma-contiguous.h>

#include <linux/dma-iommu.h>

#include <linux/vmalloc.h>

#include <linux/swiotlb.h>

#include <linux/pci.h>
@@ -58,37 +59,6 @@ void arch_dma_prep_coherent(struct page *page, size_t size) 
	__dma_flush_area(page_address(page), size);

}



#ifdef CONFIG_IOMMU_DMA

static int __swiotlb_get_sgtable_page(struct sg_table *sgt,

				      struct page *page, size_t size)

{

	int ret = sg_alloc_table(sgt, 1, GFP_KERNEL);



	if (!ret)

		sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);



	return ret;

}



static int __swiotlb_mmap_pfn(struct vm_area_struct *vma,

			      unsigned long pfn, size_t size)

{

	int ret = -ENXIO;

	unsigned long nr_vma_pages = vma_pages(vma);

	unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;

	unsigned long off = vma->vm_pgoff;



	if (off < nr_pages && nr_vma_pages <= (nr_pages - off)) {

		ret = remap_pfn_range(vma, vma->vm_start,

				      pfn + off,

				      vma->vm_end - vma->vm_start,

				      vma->vm_page_prot);

	}



	return ret;

}

#endif /* CONFIG_IOMMU_DMA */



static int __init arm64_dma_init(void)

{

	WARN_TAINT(ARCH_DMA_MINALIGN < cache_line_size(),
@@ -100,374 +70,18 @@ static int __init arm64_dma_init(void) 
arch_initcall(arm64_dma_init);



#ifdef CONFIG_IOMMU_DMA

#include <linux/dma-iommu.h>

#include <linux/platform_device.h>

#include <linux/amba/bus.h>



static void *__iommu_alloc_attrs(struct device *dev, size_t size,

				 dma_addr_t *handle, gfp_t gfp,

				 unsigned long attrs)

{

	bool coherent = dev_is_dma_coherent(dev);

	int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs);

	size_t iosize = size;

	void *addr;



	if (WARN(!dev, "cannot create IOMMU mapping for unknown device\n"))

		return NULL;



	size = PAGE_ALIGN(size);



	/*

	 * Some drivers rely on this, and we probably don't want the

	 * possibility of stale kernel data being read by devices anyway.

	 */

	gfp |= __GFP_ZERO;



	if (!gfpflags_allow_blocking(gfp)) {

		struct page *page;

		/*

		 * In atomic context we can't remap anything, so we'll only

		 * get the virtually contiguous buffer we need by way of a

		 * physically contiguous allocation.

		 */

		if (coherent) {

			page = alloc_pages(gfp, get_order(size));

			addr = page ? page_address(page) : NULL;

		} else {

			addr = dma_alloc_from_pool(size, &page, gfp);

		}

		if (!addr)

			return NULL;



		*handle = iommu_dma_map_page(dev, page, 0, iosize, ioprot);

		if (*handle == DMA_MAPPING_ERROR) {

			if (coherent)

				__free_pages(page, get_order(size));

			else

				dma_free_from_pool(addr, size);

			addr = NULL;

		}

	} else if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {

		pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs);

		struct page *page;



		page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT,

					get_order(size), gfp & __GFP_NOWARN);

		if (!page)

			return NULL;



		*handle = iommu_dma_map_page(dev, page, 0, iosize, ioprot);

		if (*handle == DMA_MAPPING_ERROR) {

			dma_release_from_contiguous(dev, page,

						    size >> PAGE_SHIFT);

			return NULL;

		}

		addr = dma_common_contiguous_remap(page, size, VM_USERMAP,

						   prot,

						   __builtin_return_address(0));

		if (addr) {

			if (!coherent)

				__dma_flush_area(page_to_virt(page), iosize);

			memset(addr, 0, size);

		} else {

			iommu_dma_unmap_page(dev, *handle, iosize, 0, attrs);

			dma_release_from_contiguous(dev, page,

						    size >> PAGE_SHIFT);

		}

	} else {

		pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs);

		struct page **pages;



		pages = iommu_dma_alloc(dev, iosize, gfp, attrs, ioprot,

					handle);

		if (!pages)

			return NULL;



		addr = dma_common_pages_remap(pages, size, VM_USERMAP, prot,

					      __builtin_return_address(0));

		if (!addr)

			iommu_dma_free(dev, pages, iosize, handle);

	}

	return addr;

}



static void __iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,

			       dma_addr_t handle, unsigned long attrs)

{

	size_t iosize = size;



	size = PAGE_ALIGN(size);

	/*

	 * @cpu_addr will be one of 4 things depending on how it was allocated:

	 * - A remapped array of pages for contiguous allocations.

	 * - A remapped array of pages from iommu_dma_alloc(), for all

	 *   non-atomic allocations.

	 * - A non-cacheable alias from the atomic pool, for atomic

	 *   allocations by non-coherent devices.

	 * - A normal lowmem address, for atomic allocations by

	 *   coherent devices.

	 * Hence how dodgy the below logic looks...

	 */

	if (dma_in_atomic_pool(cpu_addr, size)) {

		iommu_dma_unmap_page(dev, handle, iosize, 0, 0);

		dma_free_from_pool(cpu_addr, size);

	} else if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {

		struct page *page = vmalloc_to_page(cpu_addr);



		iommu_dma_unmap_page(dev, handle, iosize, 0, attrs);

		dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT);

		dma_common_free_remap(cpu_addr, size, VM_USERMAP);

	} else if (is_vmalloc_addr(cpu_addr)){

		struct vm_struct *area = find_vm_area(cpu_addr);



		if (WARN_ON(!area || !area->pages))

			return;

		iommu_dma_free(dev, area->pages, iosize, &handle);

		dma_common_free_remap(cpu_addr, size, VM_USERMAP);

	} else {

		iommu_dma_unmap_page(dev, handle, iosize, 0, 0);

		__free_pages(virt_to_page(cpu_addr), get_order(size));

	}

}



static int __iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma,

			      void *cpu_addr, dma_addr_t dma_addr, size_t size,

			      unsigned long attrs)

{

	struct vm_struct *area;

	int ret;



	vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, attrs);



	if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))

		return ret;



	if (!is_vmalloc_addr(cpu_addr)) {

		unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));

		return __swiotlb_mmap_pfn(vma, pfn, size);

	}



	if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {

		/*

		 * DMA_ATTR_FORCE_CONTIGUOUS allocations are always remapped,

		 * hence in the vmalloc space.

		 */

		unsigned long pfn = vmalloc_to_pfn(cpu_addr);

		return __swiotlb_mmap_pfn(vma, pfn, size);

	}



	area = find_vm_area(cpu_addr);

	if (WARN_ON(!area || !area->pages))

		return -ENXIO;



	return iommu_dma_mmap(area->pages, size, vma);

}



static int __iommu_get_sgtable(struct device *dev, struct sg_table *sgt,

			       void *cpu_addr, dma_addr_t dma_addr,

			       size_t size, unsigned long attrs)

{

	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;

	struct vm_struct *area = find_vm_area(cpu_addr);



	if (!is_vmalloc_addr(cpu_addr)) {

		struct page *page = virt_to_page(cpu_addr);

		return __swiotlb_get_sgtable_page(sgt, page, size);

	}



	if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {

		/*

		 * DMA_ATTR_FORCE_CONTIGUOUS allocations are always remapped,

		 * hence in the vmalloc space.

		 */

		struct page *page = vmalloc_to_page(cpu_addr);

		return __swiotlb_get_sgtable_page(sgt, page, size);

	}



	if (WARN_ON(!area || !area->pages))

		return -ENXIO;



	return sg_alloc_table_from_pages(sgt, area->pages, count, 0, size,

					 GFP_KERNEL);

}



static void __iommu_sync_single_for_cpu(struct device *dev,

					dma_addr_t dev_addr, size_t size,

					enum dma_data_direction dir)

{

	phys_addr_t phys;



	if (dev_is_dma_coherent(dev))

		return;



	phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dev_addr);

	arch_sync_dma_for_cpu(dev, phys, size, dir);

}



static void __iommu_sync_single_for_device(struct device *dev,

					   dma_addr_t dev_addr, size_t size,

					   enum dma_data_direction dir)

{

	phys_addr_t phys;



	if (dev_is_dma_coherent(dev))

		return;



	phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dev_addr);

	arch_sync_dma_for_device(dev, phys, size, dir);

}



static dma_addr_t __iommu_map_page(struct device *dev, struct page *page,

				   unsigned long offset, size_t size,

				   enum dma_data_direction dir,

				   unsigned long attrs)

{

	bool coherent = dev_is_dma_coherent(dev);

	int prot = dma_info_to_prot(dir, coherent, attrs);

	dma_addr_t dev_addr = iommu_dma_map_page(dev, page, offset, size, prot);



	if (!coherent && !(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&

	    dev_addr != DMA_MAPPING_ERROR)

		__dma_map_area(page_address(page) + offset, size, dir);



	return dev_addr;

}



static void __iommu_unmap_page(struct device *dev, dma_addr_t dev_addr,

			       size_t size, enum dma_data_direction dir,

			       unsigned long attrs)

{

	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)

		__iommu_sync_single_for_cpu(dev, dev_addr, size, dir);



	iommu_dma_unmap_page(dev, dev_addr, size, dir, attrs);

}



static void __iommu_sync_sg_for_cpu(struct device *dev,

				    struct scatterlist *sgl, int nelems,

				    enum dma_data_direction dir)

{

	struct scatterlist *sg;

	int i;



	if (dev_is_dma_coherent(dev))

		return;



	for_each_sg(sgl, sg, nelems, i)

		arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir);

}



static void __iommu_sync_sg_for_device(struct device *dev,

				       struct scatterlist *sgl, int nelems,

				       enum dma_data_direction dir)

{

	struct scatterlist *sg;

	int i;



	if (dev_is_dma_coherent(dev))

		return;



	for_each_sg(sgl, sg, nelems, i)

		arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir);

}



static int __iommu_map_sg_attrs(struct device *dev, struct scatterlist *sgl,

				int nelems, enum dma_data_direction dir,

				unsigned long attrs)

{

	bool coherent = dev_is_dma_coherent(dev);



	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)

		__iommu_sync_sg_for_device(dev, sgl, nelems, dir);



	return iommu_dma_map_sg(dev, sgl, nelems,

				dma_info_to_prot(dir, coherent, attrs));

}



static void __iommu_unmap_sg_attrs(struct device *dev,

				   struct scatterlist *sgl, int nelems,

				   enum dma_data_direction dir,

				   unsigned long attrs)

{

	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)

		__iommu_sync_sg_for_cpu(dev, sgl, nelems, dir);



	iommu_dma_unmap_sg(dev, sgl, nelems, dir, attrs);

}



static const struct dma_map_ops iommu_dma_ops = {

	.alloc = __iommu_alloc_attrs,

	.free = __iommu_free_attrs,

	.mmap = __iommu_mmap_attrs,

	.get_sgtable = __iommu_get_sgtable,

	.map_page = __iommu_map_page,

	.unmap_page = __iommu_unmap_page,

	.map_sg = __iommu_map_sg_attrs,

	.unmap_sg = __iommu_unmap_sg_attrs,

	.sync_single_for_cpu = __iommu_sync_single_for_cpu,

	.sync_single_for_device = __iommu_sync_single_for_device,

	.sync_sg_for_cpu = __iommu_sync_sg_for_cpu,

	.sync_sg_for_device = __iommu_sync_sg_for_device,

	.map_resource = iommu_dma_map_resource,

	.unmap_resource = iommu_dma_unmap_resource,

};



static int __init __iommu_dma_init(void)

{

	return iommu_dma_init();

}

arch_initcall(__iommu_dma_init);



static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,

				  const struct iommu_ops *ops)

{

	struct iommu_domain *domain;



	if (!ops)

		return;



	/*

	 * The IOMMU core code allocates the default DMA domain, which the

	 * underlying IOMMU driver needs to support via the dma-iommu layer.

	 */

	domain = iommu_get_domain_for_dev(dev);



	if (!domain)

		goto out_err;



	if (domain->type == IOMMU_DOMAIN_DMA) {

		if (iommu_dma_init_domain(domain, dma_base, size, dev))

			goto out_err;



		dev->dma_ops = &iommu_dma_ops;

	}



	return;



out_err:

	 pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n",

		 dev_name(dev));

}



void arch_teardown_dma_ops(struct device *dev)

{

	dev->dma_ops = NULL;

}



#else



static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,

				  const struct iommu_ops *iommu)

{ }



#endif  /* CONFIG_IOMMU_DMA */

#endif



void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,

			const struct iommu_ops *iommu, bool coherent)

{

	dev->dma_coherent = coherent;

	__iommu_setup_dma_ops(dev, dma_base, size, iommu);

	if (iommu)

		iommu_setup_dma_ops(dev, dma_base, size);



#ifdef CONFIG_XEN

	if (xen_initial_domain())

drivers/iommu/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -97,6 +97,7 @@ config IOMMU_DMA 
	select IOMMU_IOVA

	select IRQ_MSI_IOMMU

	select NEED_SG_DMA_LENGTH

	depends on DMA_DIRECT_REMAP



config FSL_PAMU

	bool "Freescale IOMMU support"

drivers/iommu/dma-iommu.c

+370 −28

File changed.

Preview size limit exceeded, changes collapsed.

include/linux/dma-iommu.h

+3 −39
Original line number Diff line number Diff line
@@ -24,49 +24,13 @@ 
#include <linux/iommu.h>

#include <linux/msi.h>



int iommu_dma_init(void);



/* Domain management interface for IOMMU drivers */

int iommu_get_dma_cookie(struct iommu_domain *domain);

int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base);

void iommu_put_dma_cookie(struct iommu_domain *domain);



/* Setup call for arch DMA mapping code */

int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,

		u64 size, struct device *dev);



/* General helpers for DMA-API <-> IOMMU-API interaction */

int dma_info_to_prot(enum dma_data_direction dir, bool coherent,

		     unsigned long attrs);



/*

 * These implement the bulk of the relevant DMA mapping callbacks, but require

 * the arch code to take care of attributes and cache maintenance

 */

struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,

		unsigned long attrs, int prot, dma_addr_t *handle);

void iommu_dma_free(struct device *dev, struct page **pages, size_t size,

		dma_addr_t *handle);



int iommu_dma_mmap(struct page **pages, size_t size, struct vm_area_struct *vma);



dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,

		unsigned long offset, size_t size, int prot);

int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg,

		int nents, int prot);



/*

 * Arch code with no special attribute handling may use these

 * directly as DMA mapping callbacks for simplicity

 */

void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,

		enum dma_data_direction dir, unsigned long attrs);

void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,

		enum dma_data_direction dir, unsigned long attrs);

dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys,

		size_t size, enum dma_data_direction dir, unsigned long attrs);

void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle,

		size_t size, enum dma_data_direction dir, unsigned long attrs);

void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size);



/* The DMA API isn't _quite_ the whole story, though... */

/*
@@ -91,9 +55,9 @@ struct msi_desc; 
struct msi_msg;

struct device;



static inline int iommu_dma_init(void)

static inline void iommu_setup_dma_ops(struct device *dev, u64 dma_base,

		u64 size)

{

	return 0;

}



static inline int iommu_get_dma_cookie(struct iommu_domain *domain)