Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/kernel/dma/ops_helpers.c b/kernel/dma/ops_helpers.c
new file mode 100644
index 0000000..af4a6ef
--- /dev/null
+++ b/kernel/dma/ops_helpers.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helpers for DMA ops implementations. These generally rely on the fact that
+ * the allocated memory contains normal pages in the direct kernel mapping.
+ */
+#include <linux/dma-map-ops.h>
+
+static struct page *dma_common_vaddr_to_page(void *cpu_addr)
+{
+ if (is_vmalloc_addr(cpu_addr))
+ return vmalloc_to_page(cpu_addr);
+ return virt_to_page(cpu_addr);
+}
+
+/*
+ * 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 dma_addr, size_t size,
+ unsigned long attrs)
+{
+ struct page *page = dma_common_vaddr_to_page(cpu_addr);
+ int ret;
+
+ ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
+ if (!ret)
+ sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
+ return ret;
+}
+
+/*
+ * 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,
+ unsigned long attrs)
+{
+#ifdef CONFIG_MMU
+ unsigned long user_count = vma_pages(vma);
+ unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ unsigned long off = vma->vm_pgoff;
+ struct page *page = dma_common_vaddr_to_page(cpu_addr);
+ int ret = -ENXIO;
+
+ vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs);
+
+ if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
+ return ret;
+
+ if (off >= count || user_count > count - off)
+ return -ENXIO;
+
+ return remap_pfn_range(vma, vma->vm_start,
+ page_to_pfn(page) + vma->vm_pgoff,
+ user_count << PAGE_SHIFT, vma->vm_page_prot);
+#else
+ return -ENXIO;
+#endif /* CONFIG_MMU */
+}
+
+struct page *dma_common_alloc_pages(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ struct page *page;
+
+ page = dma_alloc_contiguous(dev, size, gfp);
+ if (!page)
+ page = alloc_pages_node(dev_to_node(dev), gfp, get_order(size));
+ if (!page)
+ return NULL;
+
+ *dma_handle = ops->map_page(dev, page, 0, size, dir,
+ DMA_ATTR_SKIP_CPU_SYNC);
+ if (*dma_handle == DMA_MAPPING_ERROR) {
+ dma_free_contiguous(dev, page, size);
+ return NULL;
+ }
+
+ memset(page_address(page), 0, size);
+ return page;
+}
+
+void dma_common_free_pages(struct device *dev, size_t size, struct page *page,
+ dma_addr_t dma_handle, enum dma_data_direction dir)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ if (ops->unmap_page)
+ ops->unmap_page(dev, dma_handle, size, dir,
+ DMA_ATTR_SKIP_CPU_SYNC);
+ dma_free_contiguous(dev, page, size);
+}