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: Christoph Hellwig <h...@lst.de> --- arch/arm64/mm/dma-mapping.c | 389 +----------------------------------- drivers/iommu/Kconfig | 1 + drivers/iommu/dma-iommu.c | 383 ++++++++++++++++++++++++++++++++--- include/linux/dma-iommu.h | 44 +--- 4 files changed, 365 insertions(+), 452 deletions(-) diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 54787a3d4ad9..bf49e982c978 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -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> @@ -58,27 +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) -{ - return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, - vma->vm_end - vma->vm_start, - vma->vm_page_prot); -} -#endif /* CONFIG_IOMMU_DMA */ - static int __init arm64_dma_init(void) { WARN_TAINT(ARCH_DMA_MINALIGN < cache_line_size(), @@ -90,379 +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) -{ - unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; - unsigned long off = vma->vm_pgoff; - 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 (off >= nr_pages || vma_pages(vma) > nr_pages - off) - return -ENXIO; - - 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, iommu); #ifdef CONFIG_XEN if (xen_initial_domain()) diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index d9a25715650e..8b13fb7d0263 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -94,6 +94,7 @@ config IOMMU_DMA select IOMMU_API select IOMMU_IOVA select NEED_SG_DMA_LENGTH + depends on DMA_DIRECT_REMAP config FSL_PAMU bool "Freescale IOMMU support" diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index ee697cfb2227..c320c52cdac4 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -21,6 +21,7 @@ #include <linux/acpi_iort.h> #include <linux/device.h> +#include <linux/dma-contiguous.h> #include <linux/dma-iommu.h> #include <linux/dma-noncoherent.h> #include <linux/gfp.h> @@ -79,11 +80,6 @@ static struct iommu_dma_cookie *cookie_alloc(enum iommu_dma_cookie_type type) return cookie; } -int iommu_dma_init(void) -{ - return iova_cache_get(); -} - /** * iommu_get_dma_cookie - Acquire DMA-API resources for a domain * @domain: IOMMU domain to prepare for DMA-API usage @@ -285,7 +281,7 @@ static void iommu_dma_flush_iotlb_all(struct iova_domain *iovad) * to ensure it is an invalid IOVA. It is safe to reinitialise a domain, but * any change which could make prior IOVAs invalid will fail. */ -int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, +static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, u64 size, struct device *dev) { struct iommu_dma_cookie *cookie = domain->iova_cookie; @@ -337,7 +333,6 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, return iova_reserve_iommu_regions(dev, domain); } -EXPORT_SYMBOL(iommu_dma_init_domain); /** * dma_info_to_prot - Translate DMA API directions and attributes to IOMMU API @@ -348,7 +343,7 @@ EXPORT_SYMBOL(iommu_dma_init_domain); * * Return: corresponding IOMMU API page protection flags */ -int dma_info_to_prot(enum dma_data_direction dir, bool coherent, +static int dma_info_to_prot(enum dma_data_direction dir, bool coherent, unsigned long attrs) { int prot = coherent ? IOMMU_CACHE : 0; @@ -507,17 +502,17 @@ static struct page **__iommu_dma_alloc_pages(struct device *dev, } /** - * iommu_dma_free - Free a buffer allocated by iommu_dma_alloc() + * iommu_dma_free - Free a buffer allocated by __iommu_dma_alloc() * @dev: Device which owns this buffer - * @pages: Array of buffer pages as returned by iommu_dma_alloc() + * @pages: Array of buffer pages as returned by __iommu_dma_alloc() * @size: Size of buffer in bytes * @handle: DMA address of buffer * * Frees both the pages associated with the buffer, and the array * describing them */ -void iommu_dma_free(struct device *dev, struct page **pages, size_t size, - dma_addr_t *handle) +static void __iommu_dma_free(struct device *dev, struct page **pages, + size_t size, dma_addr_t *handle) { __iommu_dma_unmap(iommu_get_dma_domain(dev), *handle, size); __iommu_dma_free_pages(pages, PAGE_ALIGN(size) >> PAGE_SHIFT); @@ -525,7 +520,7 @@ void iommu_dma_free(struct device *dev, struct page **pages, size_t size, } /** - * iommu_dma_alloc - Allocate and map a buffer contiguous in IOVA space + * __iommu_dma_alloc - Allocate and map a buffer contiguous in IOVA space * @dev: Device to allocate memory for. Must be a real device * attached to an iommu_dma_domain * @size: Size of buffer in bytes @@ -540,8 +535,8 @@ void iommu_dma_free(struct device *dev, struct page **pages, size_t size, * Return: Array of struct page pointers describing the buffer, * or NULL on failure. */ -struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp, - unsigned long attrs, int prot, dma_addr_t *handle) +static struct page **__iommu_dma_alloc(struct device *dev, size_t size, + gfp_t gfp, unsigned long attrs, int prot, dma_addr_t *handle) { struct iommu_domain *domain = iommu_get_dma_domain(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; @@ -603,16 +598,16 @@ struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp, } /** - * iommu_dma_mmap - Map a buffer into provided user VMA - * @pages: Array representing buffer from iommu_dma_alloc() + * __iommu_dma_mmap - Map a buffer into provided user VMA + * @pages: Array representing buffer from __iommu_dma_alloc() * @size: Size of buffer in bytes * @vma: VMA describing requested userspace mapping * * Maps the pages of the buffer in @pages into @vma. The caller is responsible * for verifying the correct size and protection of @vma beforehand. */ - -int iommu_dma_mmap(struct page **pages, size_t size, struct vm_area_struct *vma) +static int __iommu_dma_mmap(struct page **pages, size_t size, + struct vm_area_struct *vma) { unsigned long uaddr = vma->vm_start; unsigned int i, count = PAGE_ALIGN(size) >> PAGE_SHIFT; @@ -627,6 +622,58 @@ int iommu_dma_mmap(struct page **pages, size_t size, struct vm_area_struct *vma) return ret; } +static void iommu_dma_sync_single_for_cpu(struct device *dev, + dma_addr_t dma_handle, 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), dma_handle); + arch_sync_dma_for_cpu(dev, phys, size, dir); +} + +static void iommu_dma_sync_single_for_device(struct device *dev, + dma_addr_t dma_handle, 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), dma_handle); + arch_sync_dma_for_device(dev, phys, size, dir); +} + +static void iommu_dma_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_dma_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 dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, size_t size, int prot, struct iommu_domain *domain) { @@ -650,19 +697,44 @@ static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, return iova + iova_off; } -dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, +static dma_addr_t __iommu_dma_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, int prot) { return __iommu_dma_map(dev, page_to_phys(page) + offset, size, prot, iommu_get_dma_domain(dev)); } -void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size, - enum dma_data_direction dir, unsigned long attrs) +static void __iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, + size_t size, enum dma_data_direction dir, unsigned long attrs) { __iommu_dma_unmap(iommu_get_dma_domain(dev), handle, size); } +static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + phys_addr_t phys = page_to_phys(page) + offset; + bool coherent = dev_is_dma_coherent(dev); + dma_addr_t dma_handle; + + dma_handle =__iommu_dma_map(dev, phys, size, + dma_info_to_prot(dir, coherent, attrs), + iommu_get_dma_domain(dev)); + if (!coherent && !(attrs & DMA_ATTR_SKIP_CPU_SYNC) && + dma_handle != DMA_MAPPING_ERROR) + arch_sync_dma_for_device(dev, phys, size, dir); + return dma_handle; +} + +static void iommu_dma_unmap_page(struct device *dev, dma_addr_t dma_handle, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + iommu_dma_sync_single_for_cpu(dev, dma_handle, size, dir); + __iommu_dma_unmap(iommu_get_domain_for_dev(dev), dma_handle, size); +} + /* * Prepare a successfully-mapped scatterlist to give back to the caller. * @@ -745,18 +817,22 @@ static void __invalidate_sg(struct scatterlist *sg, int nents) * impedance-matching, to be able to hand off a suitably-aligned list, * but still preserve the original offsets and sizes for the caller. */ -int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, - int nents, int prot) +static int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction dir, unsigned long attrs) { struct iommu_domain *domain = iommu_get_dma_domain(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; struct iova_domain *iovad = &cookie->iovad; struct scatterlist *s, *prev = NULL; + int prot = dma_info_to_prot(dir, dev_is_dma_coherent(dev), attrs); dma_addr_t iova; size_t iova_len = 0; unsigned long mask = dma_get_seg_boundary(dev); int i; + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + iommu_dma_sync_sg_for_device(dev, sg, nents, dir); + /* * Work out how much IOVA space we need, and align the segments to * IOVA granules for the IOMMU driver to handle. With some clever @@ -816,12 +892,16 @@ int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, return 0; } -void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, - enum dma_data_direction dir, unsigned long attrs) +static void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction dir, unsigned long attrs) { dma_addr_t start, end; struct scatterlist *tmp; int i; + + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0) + iommu_dma_sync_sg_for_cpu(dev, sg, nents, dir); + /* * The scatterlist segments are mapped into a single * contiguous IOVA allocation, so this is incredibly easy. @@ -836,7 +916,7 @@ void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, __iommu_dma_unmap(iommu_get_dma_domain(dev), start, end - start); } -dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys, +static 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) { return __iommu_dma_map(dev, phys, size, @@ -844,12 +924,257 @@ dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys, iommu_get_dma_domain(dev)); } -void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle, +static void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle, size_t size, enum dma_data_direction dir, unsigned long attrs) { __iommu_dma_unmap(iommu_get_dma_domain(dev), handle, size); } +static void *iommu_dma_alloc(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; + + 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) + arch_dma_prep_coherent(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_dma_free(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_dma_mmap_pfn(struct vm_area_struct *vma, + unsigned long pfn, size_t size) +{ + return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, + vma->vm_end - vma->vm_start, + vma->vm_page_prot); +} + +static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ + unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; + unsigned long off = vma->vm_pgoff; + 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 (off >= nr_pages || vma_pages(vma) > nr_pages - off) + return -ENXIO; + + if (!is_vmalloc_addr(cpu_addr)) { + unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr)); + return __iommu_dma_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 __iommu_dma_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_dma_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 iommu_dma_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 __iommu_dma_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 __iommu_dma_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 const struct dma_map_ops iommu_dma_ops = { + .alloc = iommu_dma_alloc, + .free = iommu_dma_free, + .mmap = iommu_dma_mmap, + .get_sgtable = iommu_dma_get_sgtable, + .map_page = iommu_dma_map_page, + .unmap_page = iommu_dma_unmap_page, + .map_sg = iommu_dma_map_sg, + .unmap_sg = iommu_dma_unmap_sg, + .sync_single_for_cpu = iommu_dma_sync_single_for_cpu, + .sync_single_for_device = iommu_dma_sync_single_for_device, + .sync_sg_for_cpu = iommu_dma_sync_sg_for_cpu, + .sync_sg_for_device = iommu_dma_sync_sg_for_device, + .map_resource = iommu_dma_map_resource, + .unmap_resource = iommu_dma_unmap_resource, +}; + +/* + * The IOMMU core code allocates the default DMA domain, which the underlying + * IOMMU driver needs to support via the dma-iommu layer. + */ +void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, + const struct iommu_ops *ops) +{ + struct iommu_domain *domain = iommu_get_domain_for_dev(dev); + + if (!domain || domain->type != IOMMU_DOMAIN_DMA) + goto out_err; + 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)); +} + static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev, phys_addr_t msi_addr, struct iommu_domain *domain) { @@ -922,3 +1247,5 @@ void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg) msg->address_lo += lower_32_bits(msi_page->iova); } } + +arch_initcall(iova_cache_get); diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h index 10ef708a605c..1d1a3b58d574 100644 --- a/include/linux/dma-iommu.h +++ b/include/linux/dma-iommu.h @@ -25,49 +25,14 @@ #include <linux/msi.h> #include <linux/types.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, + const struct iommu_ops *ops); /* The DMA API isn't _quite_ the whole story, though... */ void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg); @@ -76,12 +41,13 @@ void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list); #else /* CONFIG_IOMMU_DMA */ struct iommu_domain; +struct iommu_ops; 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, const struct iommu_ops *ops) { - return 0; } static inline int iommu_get_dma_cookie(struct iommu_domain *domain) -- 2.20.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu