v4.19.13 snapshot.
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
new file mode 100644
index 0000000..1cb9c0f
--- /dev/null
+++ b/arch/arm/mm/dma-mapping.c
@@ -0,0 +1,2403 @@
+/*
+ * linux/arch/arm/mm/dma-mapping.c
+ *
+ * Copyright (C) 2000-2004 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * DMA uncached mapping support.
+ */
+#include <linux/bootmem.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/genalloc.h>
+#include <linux/gfp.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dma-contiguous.h>
+#include <linux/highmem.h>
+#include <linux/memblock.h>
+#include <linux/slab.h>
+#include <linux/iommu.h>
+#include <linux/io.h>
+#include <linux/vmalloc.h>
+#include <linux/sizes.h>
+#include <linux/cma.h>
+
+#include <asm/memory.h>
+#include <asm/highmem.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/mach/arch.h>
+#include <asm/dma-iommu.h>
+#include <asm/mach/map.h>
+#include <asm/system_info.h>
+#include <asm/dma-contiguous.h>
+
+#include "dma.h"
+#include "mm.h"
+
+struct arm_dma_alloc_args {
+ struct device *dev;
+ size_t size;
+ gfp_t gfp;
+ pgprot_t prot;
+ const void *caller;
+ bool want_vaddr;
+ int coherent_flag;
+};
+
+struct arm_dma_free_args {
+ struct device *dev;
+ size_t size;
+ void *cpu_addr;
+ struct page *page;
+ bool want_vaddr;
+};
+
+#define NORMAL 0
+#define COHERENT 1
+
+struct arm_dma_allocator {
+ void *(*alloc)(struct arm_dma_alloc_args *args,
+ struct page **ret_page);
+ void (*free)(struct arm_dma_free_args *args);
+};
+
+struct arm_dma_buffer {
+ struct list_head list;
+ void *virt;
+ struct arm_dma_allocator *allocator;
+};
+
+static LIST_HEAD(arm_dma_bufs);
+static DEFINE_SPINLOCK(arm_dma_bufs_lock);
+
+static struct arm_dma_buffer *arm_dma_buffer_find(void *virt)
+{
+ struct arm_dma_buffer *buf, *found = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&arm_dma_bufs_lock, flags);
+ list_for_each_entry(buf, &arm_dma_bufs, list) {
+ if (buf->virt == virt) {
+ list_del(&buf->list);
+ found = buf;
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&arm_dma_bufs_lock, flags);
+ return found;
+}
+
+/*
+ * The DMA API is built upon the notion of "buffer ownership". A buffer
+ * is either exclusively owned by the CPU (and therefore may be accessed
+ * by it) or exclusively owned by the DMA device. These helper functions
+ * represent the transitions between these two ownership states.
+ *
+ * Note, however, that on later ARMs, this notion does not work due to
+ * speculative prefetches. We model our approach on the assumption that
+ * the CPU does do speculative prefetches, which means we clean caches
+ * before transfers and delay cache invalidation until transfer completion.
+ *
+ */
+static void __dma_page_cpu_to_dev(struct page *, unsigned long,
+ size_t, enum dma_data_direction);
+static void __dma_page_dev_to_cpu(struct page *, unsigned long,
+ size_t, enum dma_data_direction);
+
+/**
+ * arm_dma_map_page - map a portion of a page for streaming DMA
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @page: page that buffer resides in
+ * @offset: offset into page for start of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Ensure that any data held in the cache is appropriately discarded
+ * or written back.
+ *
+ * The device owns this memory once this call has completed. The CPU
+ * can regain ownership by calling dma_unmap_page().
+ */
+static dma_addr_t arm_dma_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
+ __dma_page_cpu_to_dev(page, offset, size, dir);
+ return pfn_to_dma(dev, page_to_pfn(page)) + offset;
+}
+
+static dma_addr_t arm_coherent_dma_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ return pfn_to_dma(dev, page_to_pfn(page)) + offset;
+}
+
+/**
+ * arm_dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @handle: DMA address of buffer
+ * @size: size of buffer (same as passed to dma_map_page)
+ * @dir: DMA transfer direction (same as passed to dma_map_page)
+ *
+ * Unmap a page streaming mode DMA translation. The handle and size
+ * must match what was provided in the previous dma_map_page() call.
+ * All other usages are undefined.
+ *
+ * After this call, reads by the CPU to the buffer are guaranteed to see
+ * whatever the device wrote there.
+ */
+static void arm_dma_unmap_page(struct device *dev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+ if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
+ __dma_page_dev_to_cpu(pfn_to_page(dma_to_pfn(dev, handle)),
+ handle & ~PAGE_MASK, size, dir);
+}
+
+static void arm_dma_sync_single_for_cpu(struct device *dev,
+ dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+ unsigned int offset = handle & (PAGE_SIZE - 1);
+ struct page *page = pfn_to_page(dma_to_pfn(dev, handle-offset));
+ __dma_page_dev_to_cpu(page, offset, size, dir);
+}
+
+static void arm_dma_sync_single_for_device(struct device *dev,
+ dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+ unsigned int offset = handle & (PAGE_SIZE - 1);
+ struct page *page = pfn_to_page(dma_to_pfn(dev, handle-offset));
+ __dma_page_cpu_to_dev(page, offset, size, dir);
+}
+
+static int arm_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+ return dma_addr == ARM_MAPPING_ERROR;
+}
+
+const struct dma_map_ops arm_dma_ops = {
+ .alloc = arm_dma_alloc,
+ .free = arm_dma_free,
+ .mmap = arm_dma_mmap,
+ .get_sgtable = arm_dma_get_sgtable,
+ .map_page = arm_dma_map_page,
+ .unmap_page = arm_dma_unmap_page,
+ .map_sg = arm_dma_map_sg,
+ .unmap_sg = arm_dma_unmap_sg,
+ .sync_single_for_cpu = arm_dma_sync_single_for_cpu,
+ .sync_single_for_device = arm_dma_sync_single_for_device,
+ .sync_sg_for_cpu = arm_dma_sync_sg_for_cpu,
+ .sync_sg_for_device = arm_dma_sync_sg_for_device,
+ .mapping_error = arm_dma_mapping_error,
+ .dma_supported = arm_dma_supported,
+};
+EXPORT_SYMBOL(arm_dma_ops);
+
+static void *arm_coherent_dma_alloc(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t gfp, unsigned long attrs);
+static void arm_coherent_dma_free(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t handle, unsigned long attrs);
+static int arm_coherent_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs);
+
+const struct dma_map_ops arm_coherent_dma_ops = {
+ .alloc = arm_coherent_dma_alloc,
+ .free = arm_coherent_dma_free,
+ .mmap = arm_coherent_dma_mmap,
+ .get_sgtable = arm_dma_get_sgtable,
+ .map_page = arm_coherent_dma_map_page,
+ .map_sg = arm_dma_map_sg,
+ .mapping_error = arm_dma_mapping_error,
+ .dma_supported = arm_dma_supported,
+};
+EXPORT_SYMBOL(arm_coherent_dma_ops);
+
+static int __dma_supported(struct device *dev, u64 mask, bool warn)
+{
+ unsigned long max_dma_pfn;
+
+ /*
+ * If the mask allows for more memory than we can address,
+ * and we actually have that much memory, then we must
+ * indicate that DMA to this device is not supported.
+ */
+ if (sizeof(mask) != sizeof(dma_addr_t) &&
+ mask > (dma_addr_t)~0 &&
+ dma_to_pfn(dev, ~0) < max_pfn - 1) {
+ if (warn) {
+ dev_warn(dev, "Coherent DMA mask %#llx is larger than dma_addr_t allows\n",
+ mask);
+ dev_warn(dev, "Driver did not use or check the return value from dma_set_coherent_mask()?\n");
+ }
+ return 0;
+ }
+
+ max_dma_pfn = min(max_pfn, arm_dma_pfn_limit);
+
+ /*
+ * Translate the device's DMA mask to a PFN limit. This
+ * PFN number includes the page which we can DMA to.
+ */
+ if (dma_to_pfn(dev, mask) < max_dma_pfn) {
+ if (warn)
+ dev_warn(dev, "Coherent DMA mask %#llx (pfn %#lx-%#lx) covers a smaller range of system memory than the DMA zone pfn 0x0-%#lx\n",
+ mask,
+ dma_to_pfn(dev, 0), dma_to_pfn(dev, mask) + 1,
+ max_dma_pfn + 1);
+ return 0;
+ }
+
+ return 1;
+}
+
+static u64 get_coherent_dma_mask(struct device *dev)
+{
+ u64 mask = (u64)DMA_BIT_MASK(32);
+
+ if (dev) {
+ mask = dev->coherent_dma_mask;
+
+ /*
+ * Sanity check the DMA mask - it must be non-zero, and
+ * must be able to be satisfied by a DMA allocation.
+ */
+ if (mask == 0) {
+ dev_warn(dev, "coherent DMA mask is unset\n");
+ return 0;
+ }
+
+ if (!__dma_supported(dev, mask, true))
+ return 0;
+ }
+
+ return mask;
+}
+
+static void __dma_clear_buffer(struct page *page, size_t size, int coherent_flag)
+{
+ /*
+ * Ensure that the allocated pages are zeroed, and that any data
+ * lurking in the kernel direct-mapped region is invalidated.
+ */
+ if (PageHighMem(page)) {
+ phys_addr_t base = __pfn_to_phys(page_to_pfn(page));
+ phys_addr_t end = base + size;
+ while (size > 0) {
+ void *ptr = kmap_atomic(page);
+ memset(ptr, 0, PAGE_SIZE);
+ if (coherent_flag != COHERENT)
+ dmac_flush_range(ptr, ptr + PAGE_SIZE);
+ kunmap_atomic(ptr);
+ page++;
+ size -= PAGE_SIZE;
+ }
+ if (coherent_flag != COHERENT)
+ outer_flush_range(base, end);
+ } else {
+ void *ptr = page_address(page);
+ memset(ptr, 0, size);
+ if (coherent_flag != COHERENT) {
+ dmac_flush_range(ptr, ptr + size);
+ outer_flush_range(__pa(ptr), __pa(ptr) + size);
+ }
+ }
+}
+
+/*
+ * Allocate a DMA buffer for 'dev' of size 'size' using the
+ * specified gfp mask. Note that 'size' must be page aligned.
+ */
+static struct page *__dma_alloc_buffer(struct device *dev, size_t size,
+ gfp_t gfp, int coherent_flag)
+{
+ unsigned long order = get_order(size);
+ struct page *page, *p, *e;
+
+ page = alloc_pages(gfp, order);
+ if (!page)
+ return NULL;
+
+ /*
+ * Now split the huge page and free the excess pages
+ */
+ split_page(page, order);
+ for (p = page + (size >> PAGE_SHIFT), e = page + (1 << order); p < e; p++)
+ __free_page(p);
+
+ __dma_clear_buffer(page, size, coherent_flag);
+
+ return page;
+}
+
+/*
+ * Free a DMA buffer. 'size' must be page aligned.
+ */
+static void __dma_free_buffer(struct page *page, size_t size)
+{
+ struct page *e = page + (size >> PAGE_SHIFT);
+
+ while (page < e) {
+ __free_page(page);
+ page++;
+ }
+}
+
+static void *__alloc_from_contiguous(struct device *dev, size_t size,
+ pgprot_t prot, struct page **ret_page,
+ const void *caller, bool want_vaddr,
+ int coherent_flag, gfp_t gfp);
+
+static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp,
+ pgprot_t prot, struct page **ret_page,
+ const void *caller, bool want_vaddr);
+
+static void *
+__dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot,
+ const void *caller)
+{
+ /*
+ * DMA allocation can be mapped to user space, so lets
+ * set VM_USERMAP flags too.
+ */
+ return dma_common_contiguous_remap(page, size,
+ VM_ARM_DMA_CONSISTENT | VM_USERMAP,
+ prot, caller);
+}
+
+static void __dma_free_remap(void *cpu_addr, size_t size)
+{
+ dma_common_free_remap(cpu_addr, size,
+ VM_ARM_DMA_CONSISTENT | VM_USERMAP);
+}
+
+#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K
+static struct gen_pool *atomic_pool __ro_after_init;
+
+static size_t atomic_pool_size __initdata = DEFAULT_DMA_COHERENT_POOL_SIZE;
+
+static int __init early_coherent_pool(char *p)
+{
+ atomic_pool_size = memparse(p, &p);
+ return 0;
+}
+early_param("coherent_pool", early_coherent_pool);
+
+/*
+ * Initialise the coherent pool for atomic allocations.
+ */
+static int __init atomic_pool_init(void)
+{
+ pgprot_t prot = pgprot_dmacoherent(PAGE_KERNEL);
+ gfp_t gfp = GFP_KERNEL | GFP_DMA;
+ struct page *page;
+ void *ptr;
+
+ atomic_pool = gen_pool_create(PAGE_SHIFT, -1);
+ if (!atomic_pool)
+ goto out;
+ /*
+ * The atomic pool is only used for non-coherent allocations
+ * so we must pass NORMAL for coherent_flag.
+ */
+ if (dev_get_cma_area(NULL))
+ ptr = __alloc_from_contiguous(NULL, atomic_pool_size, prot,
+ &page, atomic_pool_init, true, NORMAL,
+ GFP_KERNEL);
+ else
+ ptr = __alloc_remap_buffer(NULL, atomic_pool_size, gfp, prot,
+ &page, atomic_pool_init, true);
+ if (ptr) {
+ int ret;
+
+ ret = gen_pool_add_virt(atomic_pool, (unsigned long)ptr,
+ page_to_phys(page),
+ atomic_pool_size, -1);
+ if (ret)
+ goto destroy_genpool;
+
+ gen_pool_set_algo(atomic_pool,
+ gen_pool_first_fit_order_align,
+ NULL);
+ pr_info("DMA: preallocated %zu KiB pool for atomic coherent allocations\n",
+ atomic_pool_size / 1024);
+ return 0;
+ }
+
+destroy_genpool:
+ gen_pool_destroy(atomic_pool);
+ atomic_pool = NULL;
+out:
+ pr_err("DMA: failed to allocate %zu KiB pool for atomic coherent allocation\n",
+ atomic_pool_size / 1024);
+ return -ENOMEM;
+}
+/*
+ * CMA is activated by core_initcall, so we must be called after it.
+ */
+postcore_initcall(atomic_pool_init);
+
+struct dma_contig_early_reserve {
+ phys_addr_t base;
+ unsigned long size;
+};
+
+static struct dma_contig_early_reserve dma_mmu_remap[MAX_CMA_AREAS] __initdata;
+
+static int dma_mmu_remap_num __initdata;
+
+void __init dma_contiguous_early_fixup(phys_addr_t base, unsigned long size)
+{
+ dma_mmu_remap[dma_mmu_remap_num].base = base;
+ dma_mmu_remap[dma_mmu_remap_num].size = size;
+ dma_mmu_remap_num++;
+}
+
+void __init dma_contiguous_remap(void)
+{
+ int i;
+ for (i = 0; i < dma_mmu_remap_num; i++) {
+ phys_addr_t start = dma_mmu_remap[i].base;
+ phys_addr_t end = start + dma_mmu_remap[i].size;
+ struct map_desc map;
+ unsigned long addr;
+
+ if (end > arm_lowmem_limit)
+ end = arm_lowmem_limit;
+ if (start >= end)
+ continue;
+
+ map.pfn = __phys_to_pfn(start);
+ map.virtual = __phys_to_virt(start);
+ map.length = end - start;
+ map.type = MT_MEMORY_DMA_READY;
+
+ /*
+ * Clear previous low-memory mapping to ensure that the
+ * TLB does not see any conflicting entries, then flush
+ * the TLB of the old entries before creating new mappings.
+ *
+ * This ensures that any speculatively loaded TLB entries
+ * (even though they may be rare) can not cause any problems,
+ * and ensures that this code is architecturally compliant.
+ */
+ for (addr = __phys_to_virt(start); addr < __phys_to_virt(end);
+ addr += PMD_SIZE)
+ pmd_clear(pmd_off_k(addr));
+
+ flush_tlb_kernel_range(__phys_to_virt(start),
+ __phys_to_virt(end));
+
+ iotable_init(&map, 1);
+ }
+}
+
+static int __dma_update_pte(pte_t *pte, pgtable_t token, unsigned long addr,
+ void *data)
+{
+ struct page *page = virt_to_page(addr);
+ pgprot_t prot = *(pgprot_t *)data;
+
+ set_pte_ext(pte, mk_pte(page, prot), 0);
+ return 0;
+}
+
+static void __dma_remap(struct page *page, size_t size, pgprot_t prot)
+{
+ unsigned long start = (unsigned long) page_address(page);
+ unsigned end = start + size;
+
+ apply_to_page_range(&init_mm, start, size, __dma_update_pte, &prot);
+ flush_tlb_kernel_range(start, end);
+}
+
+static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp,
+ pgprot_t prot, struct page **ret_page,
+ const void *caller, bool want_vaddr)
+{
+ struct page *page;
+ void *ptr = NULL;
+ /*
+ * __alloc_remap_buffer is only called when the device is
+ * non-coherent
+ */
+ page = __dma_alloc_buffer(dev, size, gfp, NORMAL);
+ if (!page)
+ return NULL;
+ if (!want_vaddr)
+ goto out;
+
+ ptr = __dma_alloc_remap(page, size, gfp, prot, caller);
+ if (!ptr) {
+ __dma_free_buffer(page, size);
+ return NULL;
+ }
+
+ out:
+ *ret_page = page;
+ return ptr;
+}
+
+static void *__alloc_from_pool(size_t size, struct page **ret_page)
+{
+ unsigned long val;
+ void *ptr = NULL;
+
+ if (!atomic_pool) {
+ WARN(1, "coherent pool not initialised!\n");
+ return NULL;
+ }
+
+ val = gen_pool_alloc(atomic_pool, size);
+ if (val) {
+ phys_addr_t phys = gen_pool_virt_to_phys(atomic_pool, val);
+
+ *ret_page = phys_to_page(phys);
+ ptr = (void *)val;
+ }
+
+ return ptr;
+}
+
+static bool __in_atomic_pool(void *start, size_t size)
+{
+ return addr_in_gen_pool(atomic_pool, (unsigned long)start, size);
+}
+
+static int __free_from_pool(void *start, size_t size)
+{
+ if (!__in_atomic_pool(start, size))
+ return 0;
+
+ gen_pool_free(atomic_pool, (unsigned long)start, size);
+
+ return 1;
+}
+
+static void *__alloc_from_contiguous(struct device *dev, size_t size,
+ pgprot_t prot, struct page **ret_page,
+ const void *caller, bool want_vaddr,
+ int coherent_flag, gfp_t gfp)
+{
+ unsigned long order = get_order(size);
+ size_t count = size >> PAGE_SHIFT;
+ struct page *page;
+ void *ptr = NULL;
+
+ page = dma_alloc_from_contiguous(dev, count, order, gfp & __GFP_NOWARN);
+ if (!page)
+ return NULL;
+
+ __dma_clear_buffer(page, size, coherent_flag);
+
+ if (!want_vaddr)
+ goto out;
+
+ if (PageHighMem(page)) {
+ ptr = __dma_alloc_remap(page, size, GFP_KERNEL, prot, caller);
+ if (!ptr) {
+ dma_release_from_contiguous(dev, page, count);
+ return NULL;
+ }
+ } else {
+ __dma_remap(page, size, prot);
+ ptr = page_address(page);
+ }
+
+ out:
+ *ret_page = page;
+ return ptr;
+}
+
+static void __free_from_contiguous(struct device *dev, struct page *page,
+ void *cpu_addr, size_t size, bool want_vaddr)
+{
+ if (want_vaddr) {
+ if (PageHighMem(page))
+ __dma_free_remap(cpu_addr, size);
+ else
+ __dma_remap(page, size, PAGE_KERNEL);
+ }
+ dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT);
+}
+
+static inline pgprot_t __get_dma_pgprot(unsigned long attrs, pgprot_t prot)
+{
+ prot = (attrs & DMA_ATTR_WRITE_COMBINE) ?
+ pgprot_writecombine(prot) :
+ pgprot_dmacoherent(prot);
+ return prot;
+}
+
+static void *__alloc_simple_buffer(struct device *dev, size_t size, gfp_t gfp,
+ struct page **ret_page)
+{
+ struct page *page;
+ /* __alloc_simple_buffer is only called when the device is coherent */
+ page = __dma_alloc_buffer(dev, size, gfp, COHERENT);
+ if (!page)
+ return NULL;
+
+ *ret_page = page;
+ return page_address(page);
+}
+
+static void *simple_allocator_alloc(struct arm_dma_alloc_args *args,
+ struct page **ret_page)
+{
+ return __alloc_simple_buffer(args->dev, args->size, args->gfp,
+ ret_page);
+}
+
+static void simple_allocator_free(struct arm_dma_free_args *args)
+{
+ __dma_free_buffer(args->page, args->size);
+}
+
+static struct arm_dma_allocator simple_allocator = {
+ .alloc = simple_allocator_alloc,
+ .free = simple_allocator_free,
+};
+
+static void *cma_allocator_alloc(struct arm_dma_alloc_args *args,
+ struct page **ret_page)
+{
+ return __alloc_from_contiguous(args->dev, args->size, args->prot,
+ ret_page, args->caller,
+ args->want_vaddr, args->coherent_flag,
+ args->gfp);
+}
+
+static void cma_allocator_free(struct arm_dma_free_args *args)
+{
+ __free_from_contiguous(args->dev, args->page, args->cpu_addr,
+ args->size, args->want_vaddr);
+}
+
+static struct arm_dma_allocator cma_allocator = {
+ .alloc = cma_allocator_alloc,
+ .free = cma_allocator_free,
+};
+
+static void *pool_allocator_alloc(struct arm_dma_alloc_args *args,
+ struct page **ret_page)
+{
+ return __alloc_from_pool(args->size, ret_page);
+}
+
+static void pool_allocator_free(struct arm_dma_free_args *args)
+{
+ __free_from_pool(args->cpu_addr, args->size);
+}
+
+static struct arm_dma_allocator pool_allocator = {
+ .alloc = pool_allocator_alloc,
+ .free = pool_allocator_free,
+};
+
+static void *remap_allocator_alloc(struct arm_dma_alloc_args *args,
+ struct page **ret_page)
+{
+ return __alloc_remap_buffer(args->dev, args->size, args->gfp,
+ args->prot, ret_page, args->caller,
+ args->want_vaddr);
+}
+
+static void remap_allocator_free(struct arm_dma_free_args *args)
+{
+ if (args->want_vaddr)
+ __dma_free_remap(args->cpu_addr, args->size);
+
+ __dma_free_buffer(args->page, args->size);
+}
+
+static struct arm_dma_allocator remap_allocator = {
+ .alloc = remap_allocator_alloc,
+ .free = remap_allocator_free,
+};
+
+static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
+ gfp_t gfp, pgprot_t prot, bool is_coherent,
+ unsigned long attrs, const void *caller)
+{
+ u64 mask = get_coherent_dma_mask(dev);
+ struct page *page = NULL;
+ void *addr;
+ bool allowblock, cma;
+ struct arm_dma_buffer *buf;
+ struct arm_dma_alloc_args args = {
+ .dev = dev,
+ .size = PAGE_ALIGN(size),
+ .gfp = gfp,
+ .prot = prot,
+ .caller = caller,
+ .want_vaddr = ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0),
+ .coherent_flag = is_coherent ? COHERENT : NORMAL,
+ };
+
+#ifdef CONFIG_DMA_API_DEBUG
+ u64 limit = (mask + 1) & ~mask;
+ if (limit && size >= limit) {
+ dev_warn(dev, "coherent allocation too big (requested %#x mask %#llx)\n",
+ size, mask);
+ return NULL;
+ }
+#endif
+
+ if (!mask)
+ return NULL;
+
+ buf = kzalloc(sizeof(*buf),
+ gfp & ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM));
+ if (!buf)
+ return NULL;
+
+ if (mask < 0xffffffffULL)
+ gfp |= GFP_DMA;
+
+ /*
+ * Following is a work-around (a.k.a. hack) to prevent pages
+ * with __GFP_COMP being passed to split_page() which cannot
+ * handle them. The real problem is that this flag probably
+ * should be 0 on ARM as it is not supported on this
+ * platform; see CONFIG_HUGETLBFS.
+ */
+ gfp &= ~(__GFP_COMP);
+ args.gfp = gfp;
+
+ *handle = ARM_MAPPING_ERROR;
+ allowblock = gfpflags_allow_blocking(gfp);
+ cma = allowblock ? dev_get_cma_area(dev) : false;
+
+ if (cma)
+ buf->allocator = &cma_allocator;
+ else if (is_coherent)
+ buf->allocator = &simple_allocator;
+ else if (allowblock)
+ buf->allocator = &remap_allocator;
+ else
+ buf->allocator = &pool_allocator;
+
+ addr = buf->allocator->alloc(&args, &page);
+
+ if (page) {
+ unsigned long flags;
+
+ *handle = pfn_to_dma(dev, page_to_pfn(page));
+ buf->virt = args.want_vaddr ? addr : page;
+
+ spin_lock_irqsave(&arm_dma_bufs_lock, flags);
+ list_add(&buf->list, &arm_dma_bufs);
+ spin_unlock_irqrestore(&arm_dma_bufs_lock, flags);
+ } else {
+ kfree(buf);
+ }
+
+ return args.want_vaddr ? addr : page;
+}
+
+/*
+ * Allocate DMA-coherent memory space and return both the kernel remapped
+ * virtual and bus address for that space.
+ */
+void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
+ gfp_t gfp, unsigned long attrs)
+{
+ pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL);
+
+ return __dma_alloc(dev, size, handle, gfp, prot, false,
+ attrs, __builtin_return_address(0));
+}
+
+static void *arm_coherent_dma_alloc(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t gfp, unsigned long attrs)
+{
+ return __dma_alloc(dev, size, handle, gfp, PAGE_KERNEL, true,
+ attrs, __builtin_return_address(0));
+}
+
+static int __arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs)
+{
+ int ret = -ENXIO;
+ unsigned long nr_vma_pages = vma_pages(vma);
+ unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ unsigned long pfn = dma_to_pfn(dev, dma_addr);
+ unsigned long off = vma->vm_pgoff;
+
+ if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
+ return ret;
+
+ 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;
+}
+
+/*
+ * Create userspace mapping for the DMA-coherent memory.
+ */
+static int arm_coherent_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs)
+{
+ return __arm_dma_mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
+}
+
+int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs)
+{
+ vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot);
+ return __arm_dma_mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
+}
+
+/*
+ * Free a buffer as defined by the above mapping.
+ */
+static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t handle, unsigned long attrs,
+ bool is_coherent)
+{
+ struct page *page = pfn_to_page(dma_to_pfn(dev, handle));
+ struct arm_dma_buffer *buf;
+ struct arm_dma_free_args args = {
+ .dev = dev,
+ .size = PAGE_ALIGN(size),
+ .cpu_addr = cpu_addr,
+ .page = page,
+ .want_vaddr = ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0),
+ };
+
+ buf = arm_dma_buffer_find(cpu_addr);
+ if (WARN(!buf, "Freeing invalid buffer %p\n", cpu_addr))
+ return;
+
+ buf->allocator->free(&args);
+ kfree(buf);
+}
+
+void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t handle, unsigned long attrs)
+{
+ __arm_dma_free(dev, size, cpu_addr, handle, attrs, false);
+}
+
+static void arm_coherent_dma_free(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t handle, unsigned long attrs)
+{
+ __arm_dma_free(dev, size, cpu_addr, handle, attrs, true);
+}
+
+/*
+ * The whole dma_get_sgtable() idea is fundamentally unsafe - it seems
+ * that the intention is to allow exporting memory allocated via the
+ * coherent DMA APIs through the dma_buf API, which only accepts a
+ * scattertable. This presents a couple of problems:
+ * 1. Not all memory allocated via the coherent DMA APIs is backed by
+ * a struct page
+ * 2. Passing coherent DMA memory into the streaming APIs is not allowed
+ * as we will try to flush the memory through a different alias to that
+ * actually being used (and the flushes are redundant.)
+ */
+int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
+ void *cpu_addr, dma_addr_t handle, size_t size,
+ unsigned long attrs)
+{
+ unsigned long pfn = dma_to_pfn(dev, handle);
+ struct page *page;
+ int ret;
+
+ /* If the PFN is not valid, we do not have a struct page */
+ if (!pfn_valid(pfn))
+ return -ENXIO;
+
+ page = pfn_to_page(pfn);
+
+ ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
+ if (unlikely(ret))
+ return ret;
+
+ sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
+ return 0;
+}
+
+static void dma_cache_maint_page(struct page *page, unsigned long offset,
+ size_t size, enum dma_data_direction dir,
+ void (*op)(const void *, size_t, int))
+{
+ unsigned long pfn;
+ size_t left = size;
+
+ pfn = page_to_pfn(page) + offset / PAGE_SIZE;
+ offset %= PAGE_SIZE;
+
+ /*
+ * A single sg entry may refer to multiple physically contiguous
+ * pages. But we still need to process highmem pages individually.
+ * If highmem is not configured then the bulk of this loop gets
+ * optimized out.
+ */
+ do {
+ size_t len = left;
+ void *vaddr;
+
+ page = pfn_to_page(pfn);
+
+ if (PageHighMem(page)) {
+ if (len + offset > PAGE_SIZE)
+ len = PAGE_SIZE - offset;
+
+ if (cache_is_vipt_nonaliasing()) {
+ vaddr = kmap_atomic(page);
+ op(vaddr + offset, len, dir);
+ kunmap_atomic(vaddr);
+ } else {
+ vaddr = kmap_high_get(page);
+ if (vaddr) {
+ op(vaddr + offset, len, dir);
+ kunmap_high(page);
+ }
+ }
+ } else {
+ vaddr = page_address(page) + offset;
+ op(vaddr, len, dir);
+ }
+ offset = 0;
+ pfn++;
+ left -= len;
+ } while (left);
+}
+
+/*
+ * Make an area consistent for devices.
+ * Note: Drivers should NOT use this function directly, as it will break
+ * platforms with CONFIG_DMABOUNCE.
+ * Use the driver DMA support - see dma-mapping.h (dma_sync_*)
+ */
+static void __dma_page_cpu_to_dev(struct page *page, unsigned long off,
+ size_t size, enum dma_data_direction dir)
+{
+ phys_addr_t paddr;
+
+ dma_cache_maint_page(page, off, size, dir, dmac_map_area);
+
+ paddr = page_to_phys(page) + off;
+ if (dir == DMA_FROM_DEVICE) {
+ outer_inv_range(paddr, paddr + size);
+ } else {
+ outer_clean_range(paddr, paddr + size);
+ }
+ /* FIXME: non-speculating: flush on bidirectional mappings? */
+}
+
+static void __dma_page_dev_to_cpu(struct page *page, unsigned long off,
+ size_t size, enum dma_data_direction dir)
+{
+ phys_addr_t paddr = page_to_phys(page) + off;
+
+ /* FIXME: non-speculating: not required */
+ /* in any case, don't bother invalidating if DMA to device */
+ if (dir != DMA_TO_DEVICE) {
+ outer_inv_range(paddr, paddr + size);
+
+ dma_cache_maint_page(page, off, size, dir, dmac_unmap_area);
+ }
+
+ /*
+ * Mark the D-cache clean for these pages to avoid extra flushing.
+ */
+ if (dir != DMA_TO_DEVICE && size >= PAGE_SIZE) {
+ unsigned long pfn;
+ size_t left = size;
+
+ pfn = page_to_pfn(page) + off / PAGE_SIZE;
+ off %= PAGE_SIZE;
+ if (off) {
+ pfn++;
+ left -= PAGE_SIZE - off;
+ }
+ while (left >= PAGE_SIZE) {
+ page = pfn_to_page(pfn++);
+ set_bit(PG_dcache_clean, &page->flags);
+ left -= PAGE_SIZE;
+ }
+ }
+}
+
+/**
+ * arm_dma_map_sg - map a set of SG buffers for streaming mode DMA
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * Map a set of buffers described by scatterlist in streaming mode for DMA.
+ * This is the scatter-gather version of the dma_map_single interface.
+ * Here the scatter gather list elements are each tagged with the
+ * appropriate dma address and length. They are obtained via
+ * sg_dma_{address,length}.
+ *
+ * Device ownership issues as mentioned for dma_map_single are the same
+ * here.
+ */
+int arm_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir, unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ struct scatterlist *s;
+ int i, j;
+
+ for_each_sg(sg, s, nents, i) {
+#ifdef CONFIG_NEED_SG_DMA_LENGTH
+ s->dma_length = s->length;
+#endif
+ s->dma_address = ops->map_page(dev, sg_page(s), s->offset,
+ s->length, dir, attrs);
+ if (dma_mapping_error(dev, s->dma_address))
+ goto bad_mapping;
+ }
+ return nents;
+
+ bad_mapping:
+ for_each_sg(sg, s, i, j)
+ ops->unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir, attrs);
+ return 0;
+}
+
+/**
+ * arm_dma_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @sg: list of buffers
+ * @nents: number of buffers to unmap (same as was passed to dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ *
+ * Unmap a set of streaming mode DMA translations. Again, CPU access
+ * rules concerning calls here are the same as for dma_unmap_single().
+ */
+void arm_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir, unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ struct scatterlist *s;
+
+ int i;
+
+ for_each_sg(sg, s, nents, i)
+ ops->unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir, attrs);
+}
+
+/**
+ * arm_dma_sync_sg_for_cpu
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @sg: list of buffers
+ * @nents: number of buffers to map (returned from dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ */
+void arm_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i)
+ ops->sync_single_for_cpu(dev, sg_dma_address(s), s->length,
+ dir);
+}
+
+/**
+ * arm_dma_sync_sg_for_device
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @sg: list of buffers
+ * @nents: number of buffers to map (returned from dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ */
+void arm_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i)
+ ops->sync_single_for_device(dev, sg_dma_address(s), s->length,
+ dir);
+}
+
+/*
+ * Return whether the given device DMA address mask can be supported
+ * properly. For example, if your device can only drive the low 24-bits
+ * during bus mastering, then you would pass 0x00ffffff as the mask
+ * to this function.
+ */
+int arm_dma_supported(struct device *dev, u64 mask)
+{
+ return __dma_supported(dev, mask, false);
+}
+
+static const struct dma_map_ops *arm_get_dma_map_ops(bool coherent)
+{
+ return coherent ? &arm_coherent_dma_ops : &arm_dma_ops;
+}
+
+#ifdef CONFIG_ARM_DMA_USE_IOMMU
+
+static int __dma_info_to_prot(enum dma_data_direction dir, unsigned long attrs)
+{
+ int prot = 0;
+
+ if (attrs & DMA_ATTR_PRIVILEGED)
+ prot |= IOMMU_PRIV;
+
+ switch (dir) {
+ case DMA_BIDIRECTIONAL:
+ return prot | IOMMU_READ | IOMMU_WRITE;
+ case DMA_TO_DEVICE:
+ return prot | IOMMU_READ;
+ case DMA_FROM_DEVICE:
+ return prot | IOMMU_WRITE;
+ default:
+ return prot;
+ }
+}
+
+/* IOMMU */
+
+static int extend_iommu_mapping(struct dma_iommu_mapping *mapping);
+
+static inline dma_addr_t __alloc_iova(struct dma_iommu_mapping *mapping,
+ size_t size)
+{
+ unsigned int order = get_order(size);
+ unsigned int align = 0;
+ unsigned int count, start;
+ size_t mapping_size = mapping->bits << PAGE_SHIFT;
+ unsigned long flags;
+ dma_addr_t iova;
+ int i;
+
+ if (order > CONFIG_ARM_DMA_IOMMU_ALIGNMENT)
+ order = CONFIG_ARM_DMA_IOMMU_ALIGNMENT;
+
+ count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ align = (1 << order) - 1;
+
+ spin_lock_irqsave(&mapping->lock, flags);
+ for (i = 0; i < mapping->nr_bitmaps; i++) {
+ start = bitmap_find_next_zero_area(mapping->bitmaps[i],
+ mapping->bits, 0, count, align);
+
+ if (start > mapping->bits)
+ continue;
+
+ bitmap_set(mapping->bitmaps[i], start, count);
+ break;
+ }
+
+ /*
+ * No unused range found. Try to extend the existing mapping
+ * and perform a second attempt to reserve an IO virtual
+ * address range of size bytes.
+ */
+ if (i == mapping->nr_bitmaps) {
+ if (extend_iommu_mapping(mapping)) {
+ spin_unlock_irqrestore(&mapping->lock, flags);
+ return ARM_MAPPING_ERROR;
+ }
+
+ start = bitmap_find_next_zero_area(mapping->bitmaps[i],
+ mapping->bits, 0, count, align);
+
+ if (start > mapping->bits) {
+ spin_unlock_irqrestore(&mapping->lock, flags);
+ return ARM_MAPPING_ERROR;
+ }
+
+ bitmap_set(mapping->bitmaps[i], start, count);
+ }
+ spin_unlock_irqrestore(&mapping->lock, flags);
+
+ iova = mapping->base + (mapping_size * i);
+ iova += start << PAGE_SHIFT;
+
+ return iova;
+}
+
+static inline void __free_iova(struct dma_iommu_mapping *mapping,
+ dma_addr_t addr, size_t size)
+{
+ unsigned int start, count;
+ size_t mapping_size = mapping->bits << PAGE_SHIFT;
+ unsigned long flags;
+ dma_addr_t bitmap_base;
+ u32 bitmap_index;
+
+ if (!size)
+ return;
+
+ bitmap_index = (u32) (addr - mapping->base) / (u32) mapping_size;
+ BUG_ON(addr < mapping->base || bitmap_index > mapping->extensions);
+
+ bitmap_base = mapping->base + mapping_size * bitmap_index;
+
+ start = (addr - bitmap_base) >> PAGE_SHIFT;
+
+ if (addr + size > bitmap_base + mapping_size) {
+ /*
+ * The address range to be freed reaches into the iova
+ * range of the next bitmap. This should not happen as
+ * we don't allow this in __alloc_iova (at the
+ * moment).
+ */
+ BUG();
+ } else
+ count = size >> PAGE_SHIFT;
+
+ spin_lock_irqsave(&mapping->lock, flags);
+ bitmap_clear(mapping->bitmaps[bitmap_index], start, count);
+ spin_unlock_irqrestore(&mapping->lock, flags);
+}
+
+/* We'll try 2M, 1M, 64K, and finally 4K; array must end with 0! */
+static const int iommu_order_array[] = { 9, 8, 4, 0 };
+
+static struct page **__iommu_alloc_buffer(struct device *dev, size_t size,
+ gfp_t gfp, unsigned long attrs,
+ int coherent_flag)
+{
+ struct page **pages;
+ int count = size >> PAGE_SHIFT;
+ int array_size = count * sizeof(struct page *);
+ int i = 0;
+ int order_idx = 0;
+
+ if (array_size <= PAGE_SIZE)
+ pages = kzalloc(array_size, GFP_KERNEL);
+ else
+ pages = vzalloc(array_size);
+ if (!pages)
+ return NULL;
+
+ if (attrs & DMA_ATTR_FORCE_CONTIGUOUS)
+ {
+ unsigned long order = get_order(size);
+ struct page *page;
+
+ page = dma_alloc_from_contiguous(dev, count, order,
+ gfp & __GFP_NOWARN);
+ if (!page)
+ goto error;
+
+ __dma_clear_buffer(page, size, coherent_flag);
+
+ for (i = 0; i < count; i++)
+ pages[i] = page + i;
+
+ return pages;
+ }
+
+ /* Go straight to 4K chunks if caller says it's OK. */
+ if (attrs & DMA_ATTR_ALLOC_SINGLE_PAGES)
+ order_idx = ARRAY_SIZE(iommu_order_array) - 1;
+
+ /*
+ * IOMMU can map any pages, so himem can also be used here
+ */
+ gfp |= __GFP_NOWARN | __GFP_HIGHMEM;
+
+ while (count) {
+ int j, order;
+
+ order = iommu_order_array[order_idx];
+
+ /* Drop down when we get small */
+ if (__fls(count) < order) {
+ order_idx++;
+ continue;
+ }
+
+ if (order) {
+ /* See if it's easy to allocate a high-order chunk */
+ pages[i] = alloc_pages(gfp | __GFP_NORETRY, order);
+
+ /* Go down a notch at first sign of pressure */
+ if (!pages[i]) {
+ order_idx++;
+ continue;
+ }
+ } else {
+ pages[i] = alloc_pages(gfp, 0);
+ if (!pages[i])
+ goto error;
+ }
+
+ if (order) {
+ split_page(pages[i], order);
+ j = 1 << order;
+ while (--j)
+ pages[i + j] = pages[i] + j;
+ }
+
+ __dma_clear_buffer(pages[i], PAGE_SIZE << order, coherent_flag);
+ i += 1 << order;
+ count -= 1 << order;
+ }
+
+ return pages;
+error:
+ while (i--)
+ if (pages[i])
+ __free_pages(pages[i], 0);
+ kvfree(pages);
+ return NULL;
+}
+
+static int __iommu_free_buffer(struct device *dev, struct page **pages,
+ size_t size, unsigned long attrs)
+{
+ int count = size >> PAGE_SHIFT;
+ int i;
+
+ if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {
+ dma_release_from_contiguous(dev, pages[0], count);
+ } else {
+ for (i = 0; i < count; i++)
+ if (pages[i])
+ __free_pages(pages[i], 0);
+ }
+
+ kvfree(pages);
+ return 0;
+}
+
+/*
+ * Create a CPU mapping for a specified pages
+ */
+static void *
+__iommu_alloc_remap(struct page **pages, size_t size, gfp_t gfp, pgprot_t prot,
+ const void *caller)
+{
+ return dma_common_pages_remap(pages, size,
+ VM_ARM_DMA_CONSISTENT | VM_USERMAP, prot, caller);
+}
+
+/*
+ * Create a mapping in device IO address space for specified pages
+ */
+static dma_addr_t
+__iommu_create_mapping(struct device *dev, struct page **pages, size_t size,
+ unsigned long attrs)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ dma_addr_t dma_addr, iova;
+ int i;
+
+ dma_addr = __alloc_iova(mapping, size);
+ if (dma_addr == ARM_MAPPING_ERROR)
+ return dma_addr;
+
+ iova = dma_addr;
+ for (i = 0; i < count; ) {
+ int ret;
+
+ unsigned int next_pfn = page_to_pfn(pages[i]) + 1;
+ phys_addr_t phys = page_to_phys(pages[i]);
+ unsigned int len, j;
+
+ for (j = i + 1; j < count; j++, next_pfn++)
+ if (page_to_pfn(pages[j]) != next_pfn)
+ break;
+
+ len = (j - i) << PAGE_SHIFT;
+ ret = iommu_map(mapping->domain, iova, phys, len,
+ __dma_info_to_prot(DMA_BIDIRECTIONAL, attrs));
+ if (ret < 0)
+ goto fail;
+ iova += len;
+ i = j;
+ }
+ return dma_addr;
+fail:
+ iommu_unmap(mapping->domain, dma_addr, iova-dma_addr);
+ __free_iova(mapping, dma_addr, size);
+ return ARM_MAPPING_ERROR;
+}
+
+static int __iommu_remove_mapping(struct device *dev, dma_addr_t iova, size_t size)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+
+ /*
+ * add optional in-page offset from iova to size and align
+ * result to page size
+ */
+ size = PAGE_ALIGN((iova & ~PAGE_MASK) + size);
+ iova &= PAGE_MASK;
+
+ iommu_unmap(mapping->domain, iova, size);
+ __free_iova(mapping, iova, size);
+ return 0;
+}
+
+static struct page **__atomic_get_pages(void *addr)
+{
+ struct page *page;
+ phys_addr_t phys;
+
+ phys = gen_pool_virt_to_phys(atomic_pool, (unsigned long)addr);
+ page = phys_to_page(phys);
+
+ return (struct page **)page;
+}
+
+static struct page **__iommu_get_pages(void *cpu_addr, unsigned long attrs)
+{
+ struct vm_struct *area;
+
+ if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
+ return __atomic_get_pages(cpu_addr);
+
+ if (attrs & DMA_ATTR_NO_KERNEL_MAPPING)
+ return cpu_addr;
+
+ area = find_vm_area(cpu_addr);
+ if (area && (area->flags & VM_ARM_DMA_CONSISTENT))
+ return area->pages;
+ return NULL;
+}
+
+static void *__iommu_alloc_simple(struct device *dev, size_t size, gfp_t gfp,
+ dma_addr_t *handle, int coherent_flag,
+ unsigned long attrs)
+{
+ struct page *page;
+ void *addr;
+
+ if (coherent_flag == COHERENT)
+ addr = __alloc_simple_buffer(dev, size, gfp, &page);
+ else
+ addr = __alloc_from_pool(size, &page);
+ if (!addr)
+ return NULL;
+
+ *handle = __iommu_create_mapping(dev, &page, size, attrs);
+ if (*handle == ARM_MAPPING_ERROR)
+ goto err_mapping;
+
+ return addr;
+
+err_mapping:
+ __free_from_pool(addr, size);
+ return NULL;
+}
+
+static void __iommu_free_atomic(struct device *dev, void *cpu_addr,
+ dma_addr_t handle, size_t size, int coherent_flag)
+{
+ __iommu_remove_mapping(dev, handle, size);
+ if (coherent_flag == COHERENT)
+ __dma_free_buffer(virt_to_page(cpu_addr), size);
+ else
+ __free_from_pool(cpu_addr, size);
+}
+
+static void *__arm_iommu_alloc_attrs(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t gfp, unsigned long attrs,
+ int coherent_flag)
+{
+ pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL);
+ struct page **pages;
+ void *addr = NULL;
+
+ *handle = ARM_MAPPING_ERROR;
+ size = PAGE_ALIGN(size);
+
+ if (coherent_flag == COHERENT || !gfpflags_allow_blocking(gfp))
+ return __iommu_alloc_simple(dev, size, gfp, handle,
+ coherent_flag, attrs);
+
+ /*
+ * Following is a work-around (a.k.a. hack) to prevent pages
+ * with __GFP_COMP being passed to split_page() which cannot
+ * handle them. The real problem is that this flag probably
+ * should be 0 on ARM as it is not supported on this
+ * platform; see CONFIG_HUGETLBFS.
+ */
+ gfp &= ~(__GFP_COMP);
+
+ pages = __iommu_alloc_buffer(dev, size, gfp, attrs, coherent_flag);
+ if (!pages)
+ return NULL;
+
+ *handle = __iommu_create_mapping(dev, pages, size, attrs);
+ if (*handle == ARM_MAPPING_ERROR)
+ goto err_buffer;
+
+ if (attrs & DMA_ATTR_NO_KERNEL_MAPPING)
+ return pages;
+
+ addr = __iommu_alloc_remap(pages, size, gfp, prot,
+ __builtin_return_address(0));
+ if (!addr)
+ goto err_mapping;
+
+ return addr;
+
+err_mapping:
+ __iommu_remove_mapping(dev, *handle, size);
+err_buffer:
+ __iommu_free_buffer(dev, pages, size, attrs);
+ return NULL;
+}
+
+static void *arm_iommu_alloc_attrs(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t gfp, unsigned long attrs)
+{
+ return __arm_iommu_alloc_attrs(dev, size, handle, gfp, attrs, NORMAL);
+}
+
+static void *arm_coherent_iommu_alloc_attrs(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t gfp, unsigned long attrs)
+{
+ return __arm_iommu_alloc_attrs(dev, size, handle, gfp, attrs, COHERENT);
+}
+
+static int __arm_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 uaddr = vma->vm_start;
+ unsigned long usize = vma->vm_end - vma->vm_start;
+ struct page **pages = __iommu_get_pages(cpu_addr, attrs);
+ unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ unsigned long off = vma->vm_pgoff;
+
+ if (!pages)
+ return -ENXIO;
+
+ if (off >= nr_pages || (usize >> PAGE_SHIFT) > nr_pages - off)
+ return -ENXIO;
+
+ pages += off;
+
+ do {
+ int ret = vm_insert_page(vma, uaddr, *pages++);
+ if (ret) {
+ pr_err("Remapping memory failed: %d\n", ret);
+ return ret;
+ }
+ uaddr += PAGE_SIZE;
+ usize -= PAGE_SIZE;
+ } while (usize > 0);
+
+ return 0;
+}
+static int arm_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)
+{
+ vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot);
+
+ return __arm_iommu_mmap_attrs(dev, vma, cpu_addr, dma_addr, size, attrs);
+}
+
+static int arm_coherent_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)
+{
+ return __arm_iommu_mmap_attrs(dev, vma, cpu_addr, dma_addr, size, attrs);
+}
+
+/*
+ * free a page as defined by the above mapping.
+ * Must not be called with IRQs disabled.
+ */
+void __arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t handle, unsigned long attrs, int coherent_flag)
+{
+ struct page **pages;
+ size = PAGE_ALIGN(size);
+
+ if (coherent_flag == COHERENT || __in_atomic_pool(cpu_addr, size)) {
+ __iommu_free_atomic(dev, cpu_addr, handle, size, coherent_flag);
+ return;
+ }
+
+ pages = __iommu_get_pages(cpu_addr, attrs);
+ if (!pages) {
+ WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
+ return;
+ }
+
+ if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0) {
+ dma_common_free_remap(cpu_addr, size,
+ VM_ARM_DMA_CONSISTENT | VM_USERMAP);
+ }
+
+ __iommu_remove_mapping(dev, handle, size);
+ __iommu_free_buffer(dev, pages, size, attrs);
+}
+
+void arm_iommu_free_attrs(struct device *dev, size_t size,
+ void *cpu_addr, dma_addr_t handle, unsigned long attrs)
+{
+ __arm_iommu_free_attrs(dev, size, cpu_addr, handle, attrs, NORMAL);
+}
+
+void arm_coherent_iommu_free_attrs(struct device *dev, size_t size,
+ void *cpu_addr, dma_addr_t handle, unsigned long attrs)
+{
+ __arm_iommu_free_attrs(dev, size, cpu_addr, handle, attrs, COHERENT);
+}
+
+static int arm_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 page **pages = __iommu_get_pages(cpu_addr, attrs);
+
+ if (!pages)
+ return -ENXIO;
+
+ return sg_alloc_table_from_pages(sgt, pages, count, 0, size,
+ GFP_KERNEL);
+}
+
+/*
+ * Map a part of the scatter-gather list into contiguous io address space
+ */
+static int __map_sg_chunk(struct device *dev, struct scatterlist *sg,
+ size_t size, dma_addr_t *handle,
+ enum dma_data_direction dir, unsigned long attrs,
+ bool is_coherent)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ dma_addr_t iova, iova_base;
+ int ret = 0;
+ unsigned int count;
+ struct scatterlist *s;
+ int prot;
+
+ size = PAGE_ALIGN(size);
+ *handle = ARM_MAPPING_ERROR;
+
+ iova_base = iova = __alloc_iova(mapping, size);
+ if (iova == ARM_MAPPING_ERROR)
+ return -ENOMEM;
+
+ for (count = 0, s = sg; count < (size >> PAGE_SHIFT); s = sg_next(s)) {
+ phys_addr_t phys = page_to_phys(sg_page(s));
+ unsigned int len = PAGE_ALIGN(s->offset + s->length);
+
+ if (!is_coherent && (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
+ __dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
+
+ prot = __dma_info_to_prot(dir, attrs);
+
+ ret = iommu_map(mapping->domain, iova, phys, len, prot);
+ if (ret < 0)
+ goto fail;
+ count += len >> PAGE_SHIFT;
+ iova += len;
+ }
+ *handle = iova_base;
+
+ return 0;
+fail:
+ iommu_unmap(mapping->domain, iova_base, count * PAGE_SIZE);
+ __free_iova(mapping, iova_base, size);
+ return ret;
+}
+
+static int __iommu_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir, unsigned long attrs,
+ bool is_coherent)
+{
+ struct scatterlist *s = sg, *dma = sg, *start = sg;
+ int i, count = 0;
+ unsigned int offset = s->offset;
+ unsigned int size = s->offset + s->length;
+ unsigned int max = dma_get_max_seg_size(dev);
+
+ for (i = 1; i < nents; i++) {
+ s = sg_next(s);
+
+ s->dma_address = ARM_MAPPING_ERROR;
+ s->dma_length = 0;
+
+ if (s->offset || (size & ~PAGE_MASK) || size + s->length > max) {
+ if (__map_sg_chunk(dev, start, size, &dma->dma_address,
+ dir, attrs, is_coherent) < 0)
+ goto bad_mapping;
+
+ dma->dma_address += offset;
+ dma->dma_length = size - offset;
+
+ size = offset = s->offset;
+ start = s;
+ dma = sg_next(dma);
+ count += 1;
+ }
+ size += s->length;
+ }
+ if (__map_sg_chunk(dev, start, size, &dma->dma_address, dir, attrs,
+ is_coherent) < 0)
+ goto bad_mapping;
+
+ dma->dma_address += offset;
+ dma->dma_length = size - offset;
+
+ return count+1;
+
+bad_mapping:
+ for_each_sg(sg, s, count, i)
+ __iommu_remove_mapping(dev, sg_dma_address(s), sg_dma_len(s));
+ return 0;
+}
+
+/**
+ * arm_coherent_iommu_map_sg - map a set of SG buffers for streaming mode DMA
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * Map a set of i/o coherent buffers described by scatterlist in streaming
+ * mode for DMA. The scatter gather list elements are merged together (if
+ * possible) and tagged with the appropriate dma address and length. They are
+ * obtained via sg_dma_{address,length}.
+ */
+int arm_coherent_iommu_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, unsigned long attrs)
+{
+ return __iommu_map_sg(dev, sg, nents, dir, attrs, true);
+}
+
+/**
+ * arm_iommu_map_sg - map a set of SG buffers for streaming mode DMA
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * Map a set of buffers described by scatterlist in streaming mode for DMA.
+ * The scatter gather list elements are merged together (if possible) and
+ * tagged with the appropriate dma address and length. They are obtained via
+ * sg_dma_{address,length}.
+ */
+int arm_iommu_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, unsigned long attrs)
+{
+ return __iommu_map_sg(dev, sg, nents, dir, attrs, false);
+}
+
+static void __iommu_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir,
+ unsigned long attrs, bool is_coherent)
+{
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i) {
+ if (sg_dma_len(s))
+ __iommu_remove_mapping(dev, sg_dma_address(s),
+ sg_dma_len(s));
+ if (!is_coherent && (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
+ __dma_page_dev_to_cpu(sg_page(s), s->offset,
+ s->length, dir);
+ }
+}
+
+/**
+ * arm_coherent_iommu_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to unmap (same as was passed to dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ *
+ * Unmap a set of streaming mode DMA translations. Again, CPU access
+ * rules concerning calls here are the same as for dma_unmap_single().
+ */
+void arm_coherent_iommu_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ __iommu_unmap_sg(dev, sg, nents, dir, attrs, true);
+}
+
+/**
+ * arm_iommu_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to unmap (same as was passed to dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ *
+ * Unmap a set of streaming mode DMA translations. Again, CPU access
+ * rules concerning calls here are the same as for dma_unmap_single().
+ */
+void arm_iommu_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ __iommu_unmap_sg(dev, sg, nents, dir, attrs, false);
+}
+
+/**
+ * arm_iommu_sync_sg_for_cpu
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map (returned from dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ */
+void arm_iommu_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir)
+{
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i)
+ __dma_page_dev_to_cpu(sg_page(s), s->offset, s->length, dir);
+
+}
+
+/**
+ * arm_iommu_sync_sg_for_device
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map (returned from dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ */
+void arm_iommu_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir)
+{
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i)
+ __dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
+}
+
+
+/**
+ * arm_coherent_iommu_map_page
+ * @dev: valid struct device pointer
+ * @page: page that buffer resides in
+ * @offset: offset into page for start of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Coherent IOMMU aware version of arm_dma_map_page()
+ */
+static dma_addr_t arm_coherent_iommu_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ dma_addr_t dma_addr;
+ int ret, prot, len = PAGE_ALIGN(size + offset);
+
+ dma_addr = __alloc_iova(mapping, len);
+ if (dma_addr == ARM_MAPPING_ERROR)
+ return dma_addr;
+
+ prot = __dma_info_to_prot(dir, attrs);
+
+ ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len, prot);
+ if (ret < 0)
+ goto fail;
+
+ return dma_addr + offset;
+fail:
+ __free_iova(mapping, dma_addr, len);
+ return ARM_MAPPING_ERROR;
+}
+
+/**
+ * arm_iommu_map_page
+ * @dev: valid struct device pointer
+ * @page: page that buffer resides in
+ * @offset: offset into page for start of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * IOMMU aware version of arm_dma_map_page()
+ */
+static dma_addr_t arm_iommu_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
+ __dma_page_cpu_to_dev(page, offset, size, dir);
+
+ return arm_coherent_iommu_map_page(dev, page, offset, size, dir, attrs);
+}
+
+/**
+ * arm_coherent_iommu_unmap_page
+ * @dev: valid struct device pointer
+ * @handle: DMA address of buffer
+ * @size: size of buffer (same as passed to dma_map_page)
+ * @dir: DMA transfer direction (same as passed to dma_map_page)
+ *
+ * Coherent IOMMU aware version of arm_dma_unmap_page()
+ */
+static void arm_coherent_iommu_unmap_page(struct device *dev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ dma_addr_t iova = handle & PAGE_MASK;
+ int offset = handle & ~PAGE_MASK;
+ int len = PAGE_ALIGN(size + offset);
+
+ if (!iova)
+ return;
+
+ iommu_unmap(mapping->domain, iova, len);
+ __free_iova(mapping, iova, len);
+}
+
+/**
+ * arm_iommu_unmap_page
+ * @dev: valid struct device pointer
+ * @handle: DMA address of buffer
+ * @size: size of buffer (same as passed to dma_map_page)
+ * @dir: DMA transfer direction (same as passed to dma_map_page)
+ *
+ * IOMMU aware version of arm_dma_unmap_page()
+ */
+static void arm_iommu_unmap_page(struct device *dev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ dma_addr_t iova = handle & PAGE_MASK;
+ struct page *page = phys_to_page(iommu_iova_to_phys(mapping->domain, iova));
+ int offset = handle & ~PAGE_MASK;
+ int len = PAGE_ALIGN(size + offset);
+
+ if (!iova)
+ return;
+
+ if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
+ __dma_page_dev_to_cpu(page, offset, size, dir);
+
+ iommu_unmap(mapping->domain, iova, len);
+ __free_iova(mapping, iova, len);
+}
+
+/**
+ * arm_iommu_map_resource - map a device resource for DMA
+ * @dev: valid struct device pointer
+ * @phys_addr: physical address of resource
+ * @size: size of resource to map
+ * @dir: DMA transfer direction
+ */
+static dma_addr_t arm_iommu_map_resource(struct device *dev,
+ phys_addr_t phys_addr, size_t size,
+ enum dma_data_direction dir, unsigned long attrs)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ dma_addr_t dma_addr;
+ int ret, prot;
+ phys_addr_t addr = phys_addr & PAGE_MASK;
+ unsigned int offset = phys_addr & ~PAGE_MASK;
+ size_t len = PAGE_ALIGN(size + offset);
+
+ dma_addr = __alloc_iova(mapping, len);
+ if (dma_addr == ARM_MAPPING_ERROR)
+ return dma_addr;
+
+ prot = __dma_info_to_prot(dir, attrs) | IOMMU_MMIO;
+
+ ret = iommu_map(mapping->domain, dma_addr, addr, len, prot);
+ if (ret < 0)
+ goto fail;
+
+ return dma_addr + offset;
+fail:
+ __free_iova(mapping, dma_addr, len);
+ return ARM_MAPPING_ERROR;
+}
+
+/**
+ * arm_iommu_unmap_resource - unmap a device DMA resource
+ * @dev: valid struct device pointer
+ * @dma_handle: DMA address to resource
+ * @size: size of resource to map
+ * @dir: DMA transfer direction
+ */
+static void arm_iommu_unmap_resource(struct device *dev, dma_addr_t dma_handle,
+ size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ dma_addr_t iova = dma_handle & PAGE_MASK;
+ unsigned int offset = dma_handle & ~PAGE_MASK;
+ size_t len = PAGE_ALIGN(size + offset);
+
+ if (!iova)
+ return;
+
+ iommu_unmap(mapping->domain, iova, len);
+ __free_iova(mapping, iova, len);
+}
+
+static void arm_iommu_sync_single_for_cpu(struct device *dev,
+ dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ dma_addr_t iova = handle & PAGE_MASK;
+ struct page *page = phys_to_page(iommu_iova_to_phys(mapping->domain, iova));
+ unsigned int offset = handle & ~PAGE_MASK;
+
+ if (!iova)
+ return;
+
+ __dma_page_dev_to_cpu(page, offset, size, dir);
+}
+
+static void arm_iommu_sync_single_for_device(struct device *dev,
+ dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+ dma_addr_t iova = handle & PAGE_MASK;
+ struct page *page = phys_to_page(iommu_iova_to_phys(mapping->domain, iova));
+ unsigned int offset = handle & ~PAGE_MASK;
+
+ if (!iova)
+ return;
+
+ __dma_page_cpu_to_dev(page, offset, size, dir);
+}
+
+const struct dma_map_ops iommu_ops = {
+ .alloc = arm_iommu_alloc_attrs,
+ .free = arm_iommu_free_attrs,
+ .mmap = arm_iommu_mmap_attrs,
+ .get_sgtable = arm_iommu_get_sgtable,
+
+ .map_page = arm_iommu_map_page,
+ .unmap_page = arm_iommu_unmap_page,
+ .sync_single_for_cpu = arm_iommu_sync_single_for_cpu,
+ .sync_single_for_device = arm_iommu_sync_single_for_device,
+
+ .map_sg = arm_iommu_map_sg,
+ .unmap_sg = arm_iommu_unmap_sg,
+ .sync_sg_for_cpu = arm_iommu_sync_sg_for_cpu,
+ .sync_sg_for_device = arm_iommu_sync_sg_for_device,
+
+ .map_resource = arm_iommu_map_resource,
+ .unmap_resource = arm_iommu_unmap_resource,
+
+ .mapping_error = arm_dma_mapping_error,
+ .dma_supported = arm_dma_supported,
+};
+
+const struct dma_map_ops iommu_coherent_ops = {
+ .alloc = arm_coherent_iommu_alloc_attrs,
+ .free = arm_coherent_iommu_free_attrs,
+ .mmap = arm_coherent_iommu_mmap_attrs,
+ .get_sgtable = arm_iommu_get_sgtable,
+
+ .map_page = arm_coherent_iommu_map_page,
+ .unmap_page = arm_coherent_iommu_unmap_page,
+
+ .map_sg = arm_coherent_iommu_map_sg,
+ .unmap_sg = arm_coherent_iommu_unmap_sg,
+
+ .map_resource = arm_iommu_map_resource,
+ .unmap_resource = arm_iommu_unmap_resource,
+
+ .mapping_error = arm_dma_mapping_error,
+ .dma_supported = arm_dma_supported,
+};
+
+/**
+ * arm_iommu_create_mapping
+ * @bus: pointer to the bus holding the client device (for IOMMU calls)
+ * @base: start address of the valid IO address space
+ * @size: maximum size of the valid IO address space
+ *
+ * Creates a mapping structure which holds information about used/unused
+ * IO address ranges, which is required to perform memory allocation and
+ * mapping with IOMMU aware functions.
+ *
+ * The client device need to be attached to the mapping with
+ * arm_iommu_attach_device function.
+ */
+struct dma_iommu_mapping *
+arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, u64 size)
+{
+ unsigned int bits = size >> PAGE_SHIFT;
+ unsigned int bitmap_size = BITS_TO_LONGS(bits) * sizeof(long);
+ struct dma_iommu_mapping *mapping;
+ int extensions = 1;
+ int err = -ENOMEM;
+
+ /* currently only 32-bit DMA address space is supported */
+ if (size > DMA_BIT_MASK(32) + 1)
+ return ERR_PTR(-ERANGE);
+
+ if (!bitmap_size)
+ return ERR_PTR(-EINVAL);
+
+ if (bitmap_size > PAGE_SIZE) {
+ extensions = bitmap_size / PAGE_SIZE;
+ bitmap_size = PAGE_SIZE;
+ }
+
+ mapping = kzalloc(sizeof(struct dma_iommu_mapping), GFP_KERNEL);
+ if (!mapping)
+ goto err;
+
+ mapping->bitmap_size = bitmap_size;
+ mapping->bitmaps = kcalloc(extensions, sizeof(unsigned long *),
+ GFP_KERNEL);
+ if (!mapping->bitmaps)
+ goto err2;
+
+ mapping->bitmaps[0] = kzalloc(bitmap_size, GFP_KERNEL);
+ if (!mapping->bitmaps[0])
+ goto err3;
+
+ mapping->nr_bitmaps = 1;
+ mapping->extensions = extensions;
+ mapping->base = base;
+ mapping->bits = BITS_PER_BYTE * bitmap_size;
+
+ spin_lock_init(&mapping->lock);
+
+ mapping->domain = iommu_domain_alloc(bus);
+ if (!mapping->domain)
+ goto err4;
+
+ kref_init(&mapping->kref);
+ return mapping;
+err4:
+ kfree(mapping->bitmaps[0]);
+err3:
+ kfree(mapping->bitmaps);
+err2:
+ kfree(mapping);
+err:
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(arm_iommu_create_mapping);
+
+static void release_iommu_mapping(struct kref *kref)
+{
+ int i;
+ struct dma_iommu_mapping *mapping =
+ container_of(kref, struct dma_iommu_mapping, kref);
+
+ iommu_domain_free(mapping->domain);
+ for (i = 0; i < mapping->nr_bitmaps; i++)
+ kfree(mapping->bitmaps[i]);
+ kfree(mapping->bitmaps);
+ kfree(mapping);
+}
+
+static int extend_iommu_mapping(struct dma_iommu_mapping *mapping)
+{
+ int next_bitmap;
+
+ if (mapping->nr_bitmaps >= mapping->extensions)
+ return -EINVAL;
+
+ next_bitmap = mapping->nr_bitmaps;
+ mapping->bitmaps[next_bitmap] = kzalloc(mapping->bitmap_size,
+ GFP_ATOMIC);
+ if (!mapping->bitmaps[next_bitmap])
+ return -ENOMEM;
+
+ mapping->nr_bitmaps++;
+
+ return 0;
+}
+
+void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping)
+{
+ if (mapping)
+ kref_put(&mapping->kref, release_iommu_mapping);
+}
+EXPORT_SYMBOL_GPL(arm_iommu_release_mapping);
+
+static int __arm_iommu_attach_device(struct device *dev,
+ struct dma_iommu_mapping *mapping)
+{
+ int err;
+
+ err = iommu_attach_device(mapping->domain, dev);
+ if (err)
+ return err;
+
+ kref_get(&mapping->kref);
+ to_dma_iommu_mapping(dev) = mapping;
+
+ pr_debug("Attached IOMMU controller to %s device.\n", dev_name(dev));
+ return 0;
+}
+
+/**
+ * arm_iommu_attach_device
+ * @dev: valid struct device pointer
+ * @mapping: io address space mapping structure (returned from
+ * arm_iommu_create_mapping)
+ *
+ * Attaches specified io address space mapping to the provided device.
+ * This replaces the dma operations (dma_map_ops pointer) with the
+ * IOMMU aware version.
+ *
+ * More than one client might be attached to the same io address space
+ * mapping.
+ */
+int arm_iommu_attach_device(struct device *dev,
+ struct dma_iommu_mapping *mapping)
+{
+ int err;
+
+ err = __arm_iommu_attach_device(dev, mapping);
+ if (err)
+ return err;
+
+ set_dma_ops(dev, &iommu_ops);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(arm_iommu_attach_device);
+
+/**
+ * arm_iommu_detach_device
+ * @dev: valid struct device pointer
+ *
+ * Detaches the provided device from a previously attached map.
+ * This voids the dma operations (dma_map_ops pointer)
+ */
+void arm_iommu_detach_device(struct device *dev)
+{
+ struct dma_iommu_mapping *mapping;
+
+ mapping = to_dma_iommu_mapping(dev);
+ if (!mapping) {
+ dev_warn(dev, "Not attached\n");
+ return;
+ }
+
+ iommu_detach_device(mapping->domain, dev);
+ kref_put(&mapping->kref, release_iommu_mapping);
+ to_dma_iommu_mapping(dev) = NULL;
+ set_dma_ops(dev, arm_get_dma_map_ops(dev->archdata.dma_coherent));
+
+ pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev));
+}
+EXPORT_SYMBOL_GPL(arm_iommu_detach_device);
+
+static const struct dma_map_ops *arm_get_iommu_dma_map_ops(bool coherent)
+{
+ return coherent ? &iommu_coherent_ops : &iommu_ops;
+}
+
+static bool arm_setup_iommu_dma_ops(struct device *dev, u64 dma_base, u64 size,
+ const struct iommu_ops *iommu)
+{
+ struct dma_iommu_mapping *mapping;
+
+ if (!iommu)
+ return false;
+
+ mapping = arm_iommu_create_mapping(dev->bus, dma_base, size);
+ if (IS_ERR(mapping)) {
+ pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",
+ size, dev_name(dev));
+ return false;
+ }
+
+ if (__arm_iommu_attach_device(dev, mapping)) {
+ pr_warn("Failed to attached device %s to IOMMU_mapping\n",
+ dev_name(dev));
+ arm_iommu_release_mapping(mapping);
+ return false;
+ }
+
+ return true;
+}
+
+static void arm_teardown_iommu_dma_ops(struct device *dev)
+{
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+
+ if (!mapping)
+ return;
+
+ arm_iommu_detach_device(dev);
+ arm_iommu_release_mapping(mapping);
+}
+
+#else
+
+static bool arm_setup_iommu_dma_ops(struct device *dev, u64 dma_base, u64 size,
+ const struct iommu_ops *iommu)
+{
+ return false;
+}
+
+static void arm_teardown_iommu_dma_ops(struct device *dev) { }
+
+#define arm_get_iommu_dma_map_ops arm_get_dma_map_ops
+
+#endif /* CONFIG_ARM_DMA_USE_IOMMU */
+
+void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+ const struct iommu_ops *iommu, bool coherent)
+{
+ const struct dma_map_ops *dma_ops;
+
+ dev->archdata.dma_coherent = coherent;
+
+ /*
+ * Don't override the dma_ops if they have already been set. Ideally
+ * this should be the only location where dma_ops are set, remove this
+ * check when all other callers of set_dma_ops will have disappeared.
+ */
+ if (dev->dma_ops)
+ return;
+
+ if (arm_setup_iommu_dma_ops(dev, dma_base, size, iommu))
+ dma_ops = arm_get_iommu_dma_map_ops(coherent);
+ else
+ dma_ops = arm_get_dma_map_ops(coherent);
+
+ set_dma_ops(dev, dma_ops);
+
+#ifdef CONFIG_XEN
+ if (xen_initial_domain()) {
+ dev->archdata.dev_dma_ops = dev->dma_ops;
+ dev->dma_ops = xen_dma_ops;
+ }
+#endif
+ dev->archdata.dma_ops_setup = true;
+}
+
+void arch_teardown_dma_ops(struct device *dev)
+{
+ if (!dev->archdata.dma_ops_setup)
+ return;
+
+ arm_teardown_iommu_dma_ops(dev);
+}