993 lines
26 KiB
C
993 lines
26 KiB
C
/*
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* SWIOTLB-based DMA API implementation
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*
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* Copyright (C) 2012 ARM Ltd.
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* Author: Catalin Marinas <catalin.marinas@arm.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <linux/gfp.h>
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#include <linux/export.h>
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#include <linux/slab.h>
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#include <linux/genalloc.h>
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#include <linux/dma-mapping.h>
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#include <linux/dma-contiguous.h>
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#include <linux/vmalloc.h>
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#include <linux/swiotlb.h>
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#include <asm/cacheflush.h>
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struct dma_map_ops *dma_ops;
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EXPORT_SYMBOL(dma_ops);
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static pgprot_t __get_dma_pgprot(struct dma_attrs *attrs, pgprot_t prot,
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bool coherent)
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{
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if (!coherent || dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs))
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return pgprot_writecombine(prot);
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return prot;
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}
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static struct gen_pool *atomic_pool;
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#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K
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static size_t atomic_pool_size = DEFAULT_DMA_COHERENT_POOL_SIZE;
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static int __init early_coherent_pool(char *p)
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{
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atomic_pool_size = memparse(p, &p);
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return 0;
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}
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early_param("coherent_pool", early_coherent_pool);
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static void *__alloc_from_pool(size_t size, struct page **ret_page, gfp_t flags)
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{
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unsigned long val;
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void *ptr = NULL;
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if (!atomic_pool) {
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WARN(1, "coherent pool not initialised!\n");
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return NULL;
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}
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val = gen_pool_alloc(atomic_pool, size);
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if (val) {
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phys_addr_t phys = gen_pool_virt_to_phys(atomic_pool, val);
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*ret_page = phys_to_page(phys);
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ptr = (void *)val;
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memset(ptr, 0, size);
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}
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return ptr;
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}
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static bool __in_atomic_pool(void *start, size_t size)
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{
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return addr_in_gen_pool(atomic_pool, (unsigned long)start, size);
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}
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static int __free_from_pool(void *start, size_t size)
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{
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if (!__in_atomic_pool(start, size))
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return 0;
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gen_pool_free(atomic_pool, (unsigned long)start, size);
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return 1;
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}
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static void *__dma_alloc_coherent(struct device *dev, size_t size,
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dma_addr_t *dma_handle, gfp_t flags,
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struct dma_attrs *attrs)
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{
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if (dev == NULL) {
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WARN_ONCE(1, "Use an actual device structure for DMA allocation\n");
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return NULL;
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}
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if (IS_ENABLED(CONFIG_ZONE_DMA) &&
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dev->coherent_dma_mask <= DMA_BIT_MASK(32))
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flags |= GFP_DMA;
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if (dev_get_cma_area(dev) && gfpflags_allow_blocking(flags)) {
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struct page *page;
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void *addr;
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page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT,
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get_order(size));
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if (!page)
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return NULL;
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*dma_handle = phys_to_dma(dev, page_to_phys(page));
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addr = page_address(page);
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memset(addr, 0, size);
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return addr;
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} else {
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return swiotlb_alloc_coherent(dev, size, dma_handle, flags);
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}
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}
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static void __dma_free_coherent(struct device *dev, size_t size,
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void *vaddr, dma_addr_t dma_handle,
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struct dma_attrs *attrs)
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{
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bool freed;
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phys_addr_t paddr = dma_to_phys(dev, dma_handle);
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if (dev == NULL) {
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WARN_ONCE(1, "Use an actual device structure for DMA allocation\n");
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return;
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}
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freed = dma_release_from_contiguous(dev,
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phys_to_page(paddr),
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size >> PAGE_SHIFT);
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if (!freed)
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swiotlb_free_coherent(dev, size, vaddr, dma_handle);
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}
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static void *__dma_alloc(struct device *dev, size_t size,
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dma_addr_t *dma_handle, gfp_t flags,
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struct dma_attrs *attrs)
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{
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struct page *page;
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void *ptr, *coherent_ptr;
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bool coherent = is_device_dma_coherent(dev);
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pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL, false);
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size = PAGE_ALIGN(size);
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if (!coherent && !gfpflags_allow_blocking(flags)) {
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struct page *page = NULL;
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void *addr = __alloc_from_pool(size, &page, flags);
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if (addr)
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*dma_handle = phys_to_dma(dev, page_to_phys(page));
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return addr;
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}
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ptr = __dma_alloc_coherent(dev, size, dma_handle, flags, attrs);
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if (!ptr)
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goto no_mem;
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/* no need for non-cacheable mapping if coherent */
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if (coherent)
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return ptr;
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/* remove any dirty cache lines on the kernel alias */
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__dma_flush_range(ptr, ptr + size);
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/* create a coherent mapping */
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page = virt_to_page(ptr);
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coherent_ptr = dma_common_contiguous_remap(page, size, VM_USERMAP,
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prot, NULL);
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if (!coherent_ptr)
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goto no_map;
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return coherent_ptr;
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no_map:
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__dma_free_coherent(dev, size, ptr, *dma_handle, attrs);
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no_mem:
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*dma_handle = DMA_ERROR_CODE;
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return NULL;
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}
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static void __dma_free(struct device *dev, size_t size,
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void *vaddr, dma_addr_t dma_handle,
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struct dma_attrs *attrs)
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{
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void *swiotlb_addr = phys_to_virt(dma_to_phys(dev, dma_handle));
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size = PAGE_ALIGN(size);
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if (!is_device_dma_coherent(dev)) {
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if (__free_from_pool(vaddr, size))
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return;
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vunmap(vaddr);
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}
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__dma_free_coherent(dev, size, swiotlb_addr, dma_handle, attrs);
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}
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static dma_addr_t __swiotlb_map_page(struct device *dev, struct page *page,
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unsigned long offset, size_t size,
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enum dma_data_direction dir,
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struct dma_attrs *attrs)
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{
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dma_addr_t dev_addr;
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dev_addr = swiotlb_map_page(dev, page, offset, size, dir, attrs);
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if (!is_device_dma_coherent(dev))
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__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
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return dev_addr;
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}
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static void __swiotlb_unmap_page(struct device *dev, dma_addr_t dev_addr,
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size_t size, enum dma_data_direction dir,
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struct dma_attrs *attrs)
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{
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if (!is_device_dma_coherent(dev))
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__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
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swiotlb_unmap_page(dev, dev_addr, size, dir, attrs);
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}
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static int __swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
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int nelems, enum dma_data_direction dir,
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struct dma_attrs *attrs)
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{
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struct scatterlist *sg;
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int i, ret;
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ret = swiotlb_map_sg_attrs(dev, sgl, nelems, dir, attrs);
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if (!is_device_dma_coherent(dev))
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for_each_sg(sgl, sg, ret, i)
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__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
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sg->length, dir);
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return ret;
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}
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static void __swiotlb_unmap_sg_attrs(struct device *dev,
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struct scatterlist *sgl, int nelems,
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enum dma_data_direction dir,
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struct dma_attrs *attrs)
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{
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struct scatterlist *sg;
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int i;
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if (!is_device_dma_coherent(dev))
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for_each_sg(sgl, sg, nelems, i)
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__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
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sg->length, dir);
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swiotlb_unmap_sg_attrs(dev, sgl, nelems, dir, attrs);
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}
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static void __swiotlb_sync_single_for_cpu(struct device *dev,
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dma_addr_t dev_addr, size_t size,
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enum dma_data_direction dir)
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{
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if (!is_device_dma_coherent(dev))
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__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
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swiotlb_sync_single_for_cpu(dev, dev_addr, size, dir);
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}
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static void __swiotlb_sync_single_for_device(struct device *dev,
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dma_addr_t dev_addr, size_t size,
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enum dma_data_direction dir)
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{
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swiotlb_sync_single_for_device(dev, dev_addr, size, dir);
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if (!is_device_dma_coherent(dev))
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__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
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}
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static void __swiotlb_sync_sg_for_cpu(struct device *dev,
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struct scatterlist *sgl, int nelems,
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enum dma_data_direction dir)
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{
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struct scatterlist *sg;
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int i;
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if (!is_device_dma_coherent(dev))
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for_each_sg(sgl, sg, nelems, i)
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__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
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sg->length, dir);
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swiotlb_sync_sg_for_cpu(dev, sgl, nelems, dir);
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}
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static void __swiotlb_sync_sg_for_device(struct device *dev,
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struct scatterlist *sgl, int nelems,
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enum dma_data_direction dir)
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{
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struct scatterlist *sg;
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int i;
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swiotlb_sync_sg_for_device(dev, sgl, nelems, dir);
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if (!is_device_dma_coherent(dev))
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for_each_sg(sgl, sg, nelems, i)
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__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
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sg->length, dir);
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}
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static int __swiotlb_mmap(struct device *dev,
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struct vm_area_struct *vma,
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void *cpu_addr, dma_addr_t dma_addr, size_t size,
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struct dma_attrs *attrs)
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{
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int ret = -ENXIO;
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unsigned long nr_vma_pages = (vma->vm_end - vma->vm_start) >>
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PAGE_SHIFT;
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unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
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unsigned long pfn = dma_to_phys(dev, dma_addr) >> PAGE_SHIFT;
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unsigned long off = vma->vm_pgoff;
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vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot,
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is_device_dma_coherent(dev));
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if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
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return ret;
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if (off < nr_pages && nr_vma_pages <= (nr_pages - off)) {
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ret = remap_pfn_range(vma, vma->vm_start,
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pfn + off,
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vma->vm_end - vma->vm_start,
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vma->vm_page_prot);
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}
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return ret;
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}
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static int __swiotlb_get_sgtable(struct device *dev, struct sg_table *sgt,
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void *cpu_addr, dma_addr_t handle, size_t size,
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struct dma_attrs *attrs)
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{
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int ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
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if (!ret)
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sg_set_page(sgt->sgl, phys_to_page(dma_to_phys(dev, handle)),
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PAGE_ALIGN(size), 0);
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return ret;
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}
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static struct dma_map_ops swiotlb_dma_ops = {
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.alloc = __dma_alloc,
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.free = __dma_free,
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.mmap = __swiotlb_mmap,
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.get_sgtable = __swiotlb_get_sgtable,
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.map_page = __swiotlb_map_page,
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.unmap_page = __swiotlb_unmap_page,
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.map_sg = __swiotlb_map_sg_attrs,
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.unmap_sg = __swiotlb_unmap_sg_attrs,
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.sync_single_for_cpu = __swiotlb_sync_single_for_cpu,
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.sync_single_for_device = __swiotlb_sync_single_for_device,
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.sync_sg_for_cpu = __swiotlb_sync_sg_for_cpu,
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.sync_sg_for_device = __swiotlb_sync_sg_for_device,
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.dma_supported = swiotlb_dma_supported,
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.mapping_error = swiotlb_dma_mapping_error,
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};
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static int __init atomic_pool_init(void)
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{
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pgprot_t prot = __pgprot(PROT_NORMAL_NC);
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unsigned long nr_pages = atomic_pool_size >> PAGE_SHIFT;
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struct page *page;
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void *addr;
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unsigned int pool_size_order = get_order(atomic_pool_size);
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if (dev_get_cma_area(NULL))
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page = dma_alloc_from_contiguous(NULL, nr_pages,
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pool_size_order);
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else
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page = alloc_pages(GFP_DMA, pool_size_order);
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if (page) {
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int ret;
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void *page_addr = page_address(page);
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memset(page_addr, 0, atomic_pool_size);
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__dma_flush_range(page_addr, page_addr + atomic_pool_size);
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atomic_pool = gen_pool_create(PAGE_SHIFT, -1);
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if (!atomic_pool)
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goto free_page;
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addr = dma_common_contiguous_remap(page, atomic_pool_size,
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VM_USERMAP, prot, atomic_pool_init);
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if (!addr)
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goto destroy_genpool;
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ret = gen_pool_add_virt(atomic_pool, (unsigned long)addr,
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page_to_phys(page),
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atomic_pool_size, -1);
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if (ret)
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goto remove_mapping;
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gen_pool_set_algo(atomic_pool,
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gen_pool_first_fit_order_align,
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(void *)PAGE_SHIFT);
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pr_info("DMA: preallocated %zu KiB pool for atomic allocations\n",
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atomic_pool_size / 1024);
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return 0;
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}
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goto out;
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remove_mapping:
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dma_common_free_remap(addr, atomic_pool_size, VM_USERMAP);
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destroy_genpool:
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gen_pool_destroy(atomic_pool);
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atomic_pool = NULL;
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free_page:
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if (!dma_release_from_contiguous(NULL, page, nr_pages))
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__free_pages(page, pool_size_order);
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out:
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pr_err("DMA: failed to allocate %zu KiB pool for atomic coherent allocation\n",
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atomic_pool_size / 1024);
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return -ENOMEM;
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}
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/********************************************
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* The following APIs are for dummy DMA ops *
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********************************************/
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static void *__dummy_alloc(struct device *dev, size_t size,
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dma_addr_t *dma_handle, gfp_t flags,
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struct dma_attrs *attrs)
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{
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return NULL;
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}
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static void __dummy_free(struct device *dev, size_t size,
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void *vaddr, dma_addr_t dma_handle,
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struct dma_attrs *attrs)
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{
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}
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static int __dummy_mmap(struct device *dev,
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struct vm_area_struct *vma,
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void *cpu_addr, dma_addr_t dma_addr, size_t size,
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struct dma_attrs *attrs)
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{
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return -ENXIO;
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}
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static dma_addr_t __dummy_map_page(struct device *dev, struct page *page,
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unsigned long offset, size_t size,
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enum dma_data_direction dir,
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struct dma_attrs *attrs)
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{
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return DMA_ERROR_CODE;
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}
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static void __dummy_unmap_page(struct device *dev, dma_addr_t dev_addr,
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size_t size, enum dma_data_direction dir,
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struct dma_attrs *attrs)
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{
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}
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static int __dummy_map_sg(struct device *dev, struct scatterlist *sgl,
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int nelems, enum dma_data_direction dir,
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struct dma_attrs *attrs)
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{
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return 0;
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}
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static void __dummy_unmap_sg(struct device *dev,
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struct scatterlist *sgl, int nelems,
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enum dma_data_direction dir,
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struct dma_attrs *attrs)
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{
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}
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static void __dummy_sync_single(struct device *dev,
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dma_addr_t dev_addr, size_t size,
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enum dma_data_direction dir)
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{
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}
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static void __dummy_sync_sg(struct device *dev,
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struct scatterlist *sgl, int nelems,
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enum dma_data_direction dir)
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{
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}
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static int __dummy_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
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{
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return 1;
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}
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static int __dummy_dma_supported(struct device *hwdev, u64 mask)
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{
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return 0;
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}
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struct dma_map_ops dummy_dma_ops = {
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.alloc = __dummy_alloc,
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.free = __dummy_free,
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.mmap = __dummy_mmap,
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|
.map_page = __dummy_map_page,
|
|
.unmap_page = __dummy_unmap_page,
|
|
.map_sg = __dummy_map_sg,
|
|
.unmap_sg = __dummy_unmap_sg,
|
|
.sync_single_for_cpu = __dummy_sync_single,
|
|
.sync_single_for_device = __dummy_sync_single,
|
|
.sync_sg_for_cpu = __dummy_sync_sg,
|
|
.sync_sg_for_device = __dummy_sync_sg,
|
|
.mapping_error = __dummy_mapping_error,
|
|
.dma_supported = __dummy_dma_supported,
|
|
};
|
|
EXPORT_SYMBOL(dummy_dma_ops);
|
|
|
|
static int __init arm64_dma_init(void)
|
|
{
|
|
int ret;
|
|
|
|
dma_ops = &swiotlb_dma_ops;
|
|
|
|
ret = atomic_pool_init();
|
|
|
|
return ret;
|
|
}
|
|
arch_initcall(arm64_dma_init);
|
|
|
|
#define PREALLOC_DMA_DEBUG_ENTRIES 4096
|
|
|
|
static int __init dma_debug_do_init(void)
|
|
{
|
|
dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
|
|
return 0;
|
|
}
|
|
fs_initcall(dma_debug_do_init);
|
|
|
|
|
|
#ifdef CONFIG_IOMMU_DMA
|
|
#include <linux/dma-iommu.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/amba/bus.h>
|
|
|
|
/* Thankfully, all cache ops are by VA so we can ignore phys here */
|
|
static void flush_page(struct device *dev, const void *virt, phys_addr_t phys)
|
|
{
|
|
__dma_flush_range(virt, virt + PAGE_SIZE);
|
|
}
|
|
|
|
static void *__iommu_alloc_attrs(struct device *dev, size_t size,
|
|
dma_addr_t *handle, gfp_t gfp,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
bool coherent = is_device_dma_coherent(dev);
|
|
int ioprot = dma_direction_to_prot(DMA_BIDIRECTIONAL, coherent);
|
|
void *addr;
|
|
|
|
if (WARN(!dev, "cannot create IOMMU mapping for unknown device\n"))
|
|
return NULL;
|
|
/*
|
|
* 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 **pages;
|
|
pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL, coherent);
|
|
|
|
pages = iommu_dma_alloc(dev, size, gfp, ioprot, handle,
|
|
flush_page);
|
|
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, size, handle);
|
|
} else {
|
|
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 = __alloc_from_pool(size, &page, gfp);
|
|
}
|
|
if (!addr)
|
|
return NULL;
|
|
|
|
*handle = iommu_dma_map_page(dev, page, 0, size, ioprot);
|
|
if (iommu_dma_mapping_error(dev, *handle)) {
|
|
if (coherent)
|
|
__free_pages(page, get_order(size));
|
|
else
|
|
__free_from_pool(addr, size);
|
|
addr = NULL;
|
|
}
|
|
}
|
|
return addr;
|
|
}
|
|
|
|
static void __iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
|
|
dma_addr_t handle, struct dma_attrs *attrs)
|
|
{
|
|
/*
|
|
* @cpu_addr will be one of 3 things depending on how it was allocated:
|
|
* - 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 (__in_atomic_pool(cpu_addr, size)) {
|
|
iommu_dma_unmap_page(dev, handle, size, 0, NULL);
|
|
__free_from_pool(cpu_addr, size);
|
|
} 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, size, &handle);
|
|
dma_common_free_remap(cpu_addr, size, VM_USERMAP);
|
|
} else {
|
|
iommu_dma_unmap_page(dev, handle, size, 0, NULL);
|
|
__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,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
struct vm_struct *area;
|
|
int ret;
|
|
|
|
vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot,
|
|
is_device_dma_coherent(dev));
|
|
|
|
if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
|
|
return ret;
|
|
|
|
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, struct dma_attrs *attrs)
|
|
{
|
|
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
|
|
struct vm_struct *area = find_vm_area(cpu_addr);
|
|
|
|
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 (is_device_dma_coherent(dev))
|
|
return;
|
|
|
|
phys = iommu_iova_to_phys(iommu_get_domain_for_dev(dev), dev_addr);
|
|
__dma_unmap_area(phys_to_virt(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 (is_device_dma_coherent(dev))
|
|
return;
|
|
|
|
phys = iommu_iova_to_phys(iommu_get_domain_for_dev(dev), dev_addr);
|
|
__dma_map_area(phys_to_virt(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,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
bool coherent = is_device_dma_coherent(dev);
|
|
int prot = dma_direction_to_prot(dir, coherent);
|
|
dma_addr_t dev_addr = iommu_dma_map_page(dev, page, offset, size, prot);
|
|
|
|
if (!iommu_dma_mapping_error(dev, dev_addr) &&
|
|
!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
|
|
__iommu_sync_single_for_device(dev, dev_addr, 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,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
|
|
__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 (is_device_dma_coherent(dev))
|
|
return;
|
|
|
|
for_each_sg(sgl, sg, nelems, i)
|
|
__dma_unmap_area(sg_virt(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 (is_device_dma_coherent(dev))
|
|
return;
|
|
|
|
for_each_sg(sgl, sg, nelems, i)
|
|
__dma_map_area(sg_virt(sg), sg->length, dir);
|
|
}
|
|
|
|
static int __iommu_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
|
|
int nelems, enum dma_data_direction dir,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
bool coherent = is_device_dma_coherent(dev);
|
|
|
|
if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
|
|
__iommu_sync_sg_for_device(dev, sgl, nelems, dir);
|
|
|
|
return iommu_dma_map_sg(dev, sgl, nelems,
|
|
dma_direction_to_prot(dir, coherent));
|
|
}
|
|
|
|
static void __iommu_unmap_sg_attrs(struct device *dev,
|
|
struct scatterlist *sgl, int nelems,
|
|
enum dma_data_direction dir,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
|
|
__iommu_sync_sg_for_cpu(dev, sgl, nelems, dir);
|
|
|
|
iommu_dma_unmap_sg(dev, sgl, nelems, dir, attrs);
|
|
}
|
|
|
|
static 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,
|
|
.dma_supported = iommu_dma_supported,
|
|
.mapping_error = iommu_dma_mapping_error,
|
|
};
|
|
|
|
/*
|
|
* TODO: Right now __iommu_setup_dma_ops() gets called too early to do
|
|
* everything it needs to - the device is only partially created and the
|
|
* IOMMU driver hasn't seen it yet, so it can't have a group. Thus we
|
|
* need this delayed attachment dance. Once IOMMU probe ordering is sorted
|
|
* to move the arch_setup_dma_ops() call later, all the notifier bits below
|
|
* become unnecessary, and will go away.
|
|
*/
|
|
struct iommu_dma_notifier_data {
|
|
struct list_head list;
|
|
struct device *dev;
|
|
const struct iommu_ops *ops;
|
|
u64 dma_base;
|
|
u64 size;
|
|
};
|
|
static LIST_HEAD(iommu_dma_masters);
|
|
static DEFINE_MUTEX(iommu_dma_notifier_lock);
|
|
|
|
/*
|
|
* Temporarily "borrow" a domain feature flag to to tell if we had to resort
|
|
* to creating our own domain here, in case we need to clean it up again.
|
|
*/
|
|
#define __IOMMU_DOMAIN_FAKE_DEFAULT (1U << 31)
|
|
|
|
static bool do_iommu_attach(struct device *dev, const struct iommu_ops *ops,
|
|
u64 dma_base, u64 size)
|
|
{
|
|
struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
|
|
|
|
/*
|
|
* Best case: The device is either part of a group which was
|
|
* already attached to a domain in a previous call, or it's
|
|
* been put in a default DMA domain by the IOMMU core.
|
|
*/
|
|
if (!domain) {
|
|
/*
|
|
* Urgh. The IOMMU core isn't going to do default domains
|
|
* for non-PCI devices anyway, until it has some means of
|
|
* abstracting the entirely implementation-specific
|
|
* sideband data/SoC topology/unicorn dust that may or
|
|
* may not differentiate upstream masters.
|
|
* So until then, HORRIBLE HACKS!
|
|
*/
|
|
domain = ops->domain_alloc(IOMMU_DOMAIN_DMA);
|
|
if (!domain)
|
|
goto out_no_domain;
|
|
|
|
domain->ops = ops;
|
|
domain->type = IOMMU_DOMAIN_DMA | __IOMMU_DOMAIN_FAKE_DEFAULT;
|
|
|
|
if (iommu_attach_device(domain, dev))
|
|
goto out_put_domain;
|
|
}
|
|
|
|
if (iommu_dma_init_domain(domain, dma_base, size))
|
|
goto out_detach;
|
|
|
|
dev->archdata.dma_ops = &iommu_dma_ops;
|
|
return true;
|
|
|
|
out_detach:
|
|
iommu_detach_device(domain, dev);
|
|
out_put_domain:
|
|
if (domain->type & __IOMMU_DOMAIN_FAKE_DEFAULT)
|
|
iommu_domain_free(domain);
|
|
out_no_domain:
|
|
pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n",
|
|
dev_name(dev));
|
|
return false;
|
|
}
|
|
|
|
static void queue_iommu_attach(struct device *dev, const struct iommu_ops *ops,
|
|
u64 dma_base, u64 size)
|
|
{
|
|
struct iommu_dma_notifier_data *iommudata;
|
|
|
|
iommudata = kzalloc(sizeof(*iommudata), GFP_KERNEL);
|
|
if (!iommudata)
|
|
return;
|
|
|
|
iommudata->dev = dev;
|
|
iommudata->ops = ops;
|
|
iommudata->dma_base = dma_base;
|
|
iommudata->size = size;
|
|
|
|
mutex_lock(&iommu_dma_notifier_lock);
|
|
list_add(&iommudata->list, &iommu_dma_masters);
|
|
mutex_unlock(&iommu_dma_notifier_lock);
|
|
}
|
|
|
|
static int __iommu_attach_notifier(struct notifier_block *nb,
|
|
unsigned long action, void *data)
|
|
{
|
|
struct iommu_dma_notifier_data *master, *tmp;
|
|
|
|
if (action != BUS_NOTIFY_ADD_DEVICE)
|
|
return 0;
|
|
|
|
mutex_lock(&iommu_dma_notifier_lock);
|
|
list_for_each_entry_safe(master, tmp, &iommu_dma_masters, list) {
|
|
if (do_iommu_attach(master->dev, master->ops,
|
|
master->dma_base, master->size)) {
|
|
list_del(&master->list);
|
|
kfree(master);
|
|
}
|
|
}
|
|
mutex_unlock(&iommu_dma_notifier_lock);
|
|
return 0;
|
|
}
|
|
|
|
static int register_iommu_dma_ops_notifier(struct bus_type *bus)
|
|
{
|
|
struct notifier_block *nb = kzalloc(sizeof(*nb), GFP_KERNEL);
|
|
int ret;
|
|
|
|
if (!nb)
|
|
return -ENOMEM;
|
|
/*
|
|
* The device must be attached to a domain before the driver probe
|
|
* routine gets a chance to start allocating DMA buffers. However,
|
|
* the IOMMU driver also needs a chance to configure the iommu_group
|
|
* via its add_device callback first, so we need to make the attach
|
|
* happen between those two points. Since the IOMMU core uses a bus
|
|
* notifier with default priority for add_device, do the same but
|
|
* with a lower priority to ensure the appropriate ordering.
|
|
*/
|
|
nb->notifier_call = __iommu_attach_notifier;
|
|
nb->priority = -100;
|
|
|
|
ret = bus_register_notifier(bus, nb);
|
|
if (ret) {
|
|
pr_warn("Failed to register DMA domain notifier; IOMMU DMA ops unavailable on bus '%s'\n",
|
|
bus->name);
|
|
kfree(nb);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int __init __iommu_dma_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = iommu_dma_init();
|
|
if (!ret)
|
|
ret = register_iommu_dma_ops_notifier(&platform_bus_type);
|
|
if (!ret)
|
|
ret = register_iommu_dma_ops_notifier(&amba_bustype);
|
|
return ret;
|
|
}
|
|
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_group *group;
|
|
|
|
if (!ops)
|
|
return;
|
|
/*
|
|
* TODO: As a concession to the future, we're ready to handle being
|
|
* called both early and late (i.e. after bus_add_device). Once all
|
|
* the platform bus code is reworked to call us late and the notifier
|
|
* junk above goes away, move the body of do_iommu_attach here.
|
|
*/
|
|
group = iommu_group_get(dev);
|
|
if (group) {
|
|
do_iommu_attach(dev, ops, dma_base, size);
|
|
iommu_group_put(group);
|
|
} else {
|
|
queue_iommu_attach(dev, ops, dma_base, size);
|
|
}
|
|
}
|
|
|
|
void arch_teardown_dma_ops(struct device *dev)
|
|
{
|
|
struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
|
|
|
|
if (domain) {
|
|
iommu_detach_device(domain, dev);
|
|
if (domain->type & __IOMMU_DOMAIN_FAKE_DEFAULT)
|
|
iommu_domain_free(domain);
|
|
}
|
|
|
|
dev->archdata.dma_ops = NULL;
|
|
}
|
|
|
|
#else
|
|
|
|
static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
|
|
struct iommu_ops *iommu)
|
|
{ }
|
|
|
|
#endif /* CONFIG_IOMMU_DMA */
|
|
|
|
void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
|
|
struct iommu_ops *iommu, bool coherent)
|
|
{
|
|
if (!acpi_disabled && !dev->archdata.dma_ops)
|
|
dev->archdata.dma_ops = dma_ops;
|
|
|
|
dev->archdata.dma_coherent = coherent;
|
|
__iommu_setup_dma_ops(dev, dma_base, size, iommu);
|
|
}
|