v4.19.13 snapshot.
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
new file mode 100644
index 0000000..d2a92dd
--- /dev/null
+++ b/kernel/dma/mapping.c
@@ -0,0 +1,345 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch-independent dma-mapping routines
+ *
+ * Copyright (c) 2006 SUSE Linux Products GmbH
+ * Copyright (c) 2006 Tejun Heo <teheo@suse.de>
+ */
+
+#include <linux/acpi.h>
+#include <linux/dma-mapping.h>
+#include <linux/export.h>
+#include <linux/gfp.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+/*
+ * Managed DMA API
+ */
+struct dma_devres {
+ size_t size;
+ void *vaddr;
+ dma_addr_t dma_handle;
+ unsigned long attrs;
+};
+
+static void dmam_release(struct device *dev, void *res)
+{
+ struct dma_devres *this = res;
+
+ dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle,
+ this->attrs);
+}
+
+static int dmam_match(struct device *dev, void *res, void *match_data)
+{
+ struct dma_devres *this = res, *match = match_data;
+
+ if (this->vaddr == match->vaddr) {
+ WARN_ON(this->size != match->size ||
+ this->dma_handle != match->dma_handle);
+ return 1;
+ }
+ return 0;
+}
+
+/**
+ * dmam_alloc_coherent - Managed dma_alloc_coherent()
+ * @dev: Device to allocate coherent memory for
+ * @size: Size of allocation
+ * @dma_handle: Out argument for allocated DMA handle
+ * @gfp: Allocation flags
+ *
+ * Managed dma_alloc_coherent(). Memory allocated using this function
+ * will be automatically released on driver detach.
+ *
+ * RETURNS:
+ * Pointer to allocated memory on success, NULL on failure.
+ */
+void *dmam_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp)
+{
+ struct dma_devres *dr;
+ void *vaddr;
+
+ dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
+ if (!dr)
+ return NULL;
+
+ vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
+ if (!vaddr) {
+ devres_free(dr);
+ return NULL;
+ }
+
+ dr->vaddr = vaddr;
+ dr->dma_handle = *dma_handle;
+ dr->size = size;
+
+ devres_add(dev, dr);
+
+ return vaddr;
+}
+EXPORT_SYMBOL(dmam_alloc_coherent);
+
+/**
+ * dmam_free_coherent - Managed dma_free_coherent()
+ * @dev: Device to free coherent memory for
+ * @size: Size of allocation
+ * @vaddr: Virtual address of the memory to free
+ * @dma_handle: DMA handle of the memory to free
+ *
+ * Managed dma_free_coherent().
+ */
+void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
+ dma_addr_t dma_handle)
+{
+ struct dma_devres match_data = { size, vaddr, dma_handle };
+
+ dma_free_coherent(dev, size, vaddr, dma_handle);
+ WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data));
+}
+EXPORT_SYMBOL(dmam_free_coherent);
+
+/**
+ * dmam_alloc_attrs - Managed dma_alloc_attrs()
+ * @dev: Device to allocate non_coherent memory for
+ * @size: Size of allocation
+ * @dma_handle: Out argument for allocated DMA handle
+ * @gfp: Allocation flags
+ * @attrs: Flags in the DMA_ATTR_* namespace.
+ *
+ * Managed dma_alloc_attrs(). Memory allocated using this function will be
+ * automatically released on driver detach.
+ *
+ * RETURNS:
+ * Pointer to allocated memory on success, NULL on failure.
+ */
+void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
+ gfp_t gfp, unsigned long attrs)
+{
+ struct dma_devres *dr;
+ void *vaddr;
+
+ dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
+ if (!dr)
+ return NULL;
+
+ vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);
+ if (!vaddr) {
+ devres_free(dr);
+ return NULL;
+ }
+
+ dr->vaddr = vaddr;
+ dr->dma_handle = *dma_handle;
+ dr->size = size;
+ dr->attrs = attrs;
+
+ devres_add(dev, dr);
+
+ return vaddr;
+}
+EXPORT_SYMBOL(dmam_alloc_attrs);
+
+#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
+
+static void dmam_coherent_decl_release(struct device *dev, void *res)
+{
+ dma_release_declared_memory(dev);
+}
+
+/**
+ * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
+ * @dev: Device to declare coherent memory for
+ * @phys_addr: Physical address of coherent memory to be declared
+ * @device_addr: Device address of coherent memory to be declared
+ * @size: Size of coherent memory to be declared
+ * @flags: Flags
+ *
+ * Managed dma_declare_coherent_memory().
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
+ dma_addr_t device_addr, size_t size, int flags)
+{
+ void *res;
+ int rc;
+
+ res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
+ if (!res)
+ return -ENOMEM;
+
+ rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,
+ flags);
+ if (!rc)
+ devres_add(dev, res);
+ else
+ devres_free(res);
+
+ return rc;
+}
+EXPORT_SYMBOL(dmam_declare_coherent_memory);
+
+/**
+ * dmam_release_declared_memory - Managed dma_release_declared_memory().
+ * @dev: Device to release declared coherent memory for
+ *
+ * Managed dmam_release_declared_memory().
+ */
+void dmam_release_declared_memory(struct device *dev)
+{
+ WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
+}
+EXPORT_SYMBOL(dmam_release_declared_memory);
+
+#endif
+
+/*
+ * Create scatter-list for the already allocated DMA buffer.
+ */
+int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
+ void *cpu_addr, dma_addr_t handle, size_t size)
+{
+ struct page *page = virt_to_page(cpu_addr);
+ int ret;
+
+ 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;
+}
+EXPORT_SYMBOL(dma_common_get_sgtable);
+
+/*
+ * Create userspace mapping for the DMA-coherent memory.
+ */
+int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size)
+{
+ int ret = -ENXIO;
+#ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
+ unsigned long user_count = vma_pages(vma);
+ unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ unsigned long off = vma->vm_pgoff;
+
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+ if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
+ return ret;
+
+ if (off < count && user_count <= (count - off))
+ ret = remap_pfn_range(vma, vma->vm_start,
+ page_to_pfn(virt_to_page(cpu_addr)) + off,
+ user_count << PAGE_SHIFT,
+ vma->vm_page_prot);
+#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
+
+ return ret;
+}
+EXPORT_SYMBOL(dma_common_mmap);
+
+#ifdef CONFIG_MMU
+static struct vm_struct *__dma_common_pages_remap(struct page **pages,
+ size_t size, unsigned long vm_flags, pgprot_t prot,
+ const void *caller)
+{
+ struct vm_struct *area;
+
+ area = get_vm_area_caller(size, vm_flags, caller);
+ if (!area)
+ return NULL;
+
+ if (map_vm_area(area, prot, pages)) {
+ vunmap(area->addr);
+ return NULL;
+ }
+
+ return area;
+}
+
+/*
+ * remaps an array of PAGE_SIZE pages into another vm_area
+ * Cannot be used in non-sleeping contexts
+ */
+void *dma_common_pages_remap(struct page **pages, size_t size,
+ unsigned long vm_flags, pgprot_t prot,
+ const void *caller)
+{
+ struct vm_struct *area;
+
+ area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
+ if (!area)
+ return NULL;
+
+ area->pages = pages;
+
+ return area->addr;
+}
+
+/*
+ * remaps an allocated contiguous region into another vm_area.
+ * Cannot be used in non-sleeping contexts
+ */
+
+void *dma_common_contiguous_remap(struct page *page, size_t size,
+ unsigned long vm_flags,
+ pgprot_t prot, const void *caller)
+{
+ int i;
+ struct page **pages;
+ struct vm_struct *area;
+
+ pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
+ if (!pages)
+ return NULL;
+
+ for (i = 0; i < (size >> PAGE_SHIFT); i++)
+ pages[i] = nth_page(page, i);
+
+ area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
+
+ kfree(pages);
+
+ if (!area)
+ return NULL;
+ return area->addr;
+}
+
+/*
+ * unmaps a range previously mapped by dma_common_*_remap
+ */
+void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
+{
+ struct vm_struct *area = find_vm_area(cpu_addr);
+
+ if (!area || (area->flags & vm_flags) != vm_flags) {
+ WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
+ return;
+ }
+
+ unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size));
+ vunmap(cpu_addr);
+}
+#endif
+
+/*
+ * enables DMA API use for a device
+ */
+int dma_configure(struct device *dev)
+{
+ if (dev->bus->dma_configure)
+ return dev->bus->dma_configure(dev);
+ return 0;
+}
+
+void dma_deconfigure(struct device *dev)
+{
+ of_dma_deconfigure(dev);
+ acpi_dma_deconfigure(dev);
+}