MIPS/jazzdma: decouple from dma-direct

The jazzdma ops implement support for a very basic IOMMU.  Thus we really
should not use the dma-direct code that takes physical address limits
into account.  This survived through the great MIPS DMA ops cleanup mostly
because I was lazy, but now it is time to fully split the implementations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/jazz/jazzdma.c

@@ -16,7 +16,6 @@
 #include <linux/memblock.h>
 #include <linux/spinlock.h>
 #include <linux/gfp.h>
-#include <linux/dma-direct.h>
 #include <linux/dma-noncoherent.h>
 #include <asm/mipsregs.h>
 #include <asm/jazz.h>
@@ -492,26 +491,39 @@ int vdma_get_enable(int channel)
 static void *jazz_dma_alloc(struct device *dev, size_t size,
 		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
+	struct page *page;
 	void *ret;
 
-	ret = dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs);
-	if (!ret)
-		return NULL;
+	if (attrs & DMA_ATTR_NO_WARN)
+		gfp |= __GFP_NOWARN;
 
-	*dma_handle = vdma_alloc(virt_to_phys(ret), size);
-	if (*dma_handle == DMA_MAPPING_ERROR) {
-		dma_direct_free_pages(dev, size, ret, *dma_handle, attrs);
+	size = PAGE_ALIGN(size);
+	page = alloc_pages(gfp, get_order(size));
+	if (!page)
 		return NULL;
-	}
+	ret = page_address(page);
+	memset(ret, 0, size);
+	*dma_handle = vdma_alloc(virt_to_phys(ret), size);
+	if (*dma_handle == DMA_MAPPING_ERROR)
+		goto out_free_pages;
+
+	if (attrs & DMA_ATTR_NON_CONSISTENT)
+		return ret;
+	arch_dma_prep_coherent(page, size);
+	return (void *)(UNCAC_BASE + __pa(ret));
 
-	return ret;
+out_free_pages:
+	__free_pages(page, get_order(size));
+	return NULL;
 }
 
 static void jazz_dma_free(struct device *dev, size_t size, void *vaddr,
 		dma_addr_t dma_handle, unsigned long attrs)
 {
 	vdma_free(dma_handle);
-	dma_direct_free_pages(dev, size, vaddr, dma_handle, attrs);
+	if (!(attrs & DMA_ATTR_NON_CONSISTENT))
+		vaddr = __va(vaddr - UNCAC_BASE);
+	__free_pages(virt_to_page(vaddr), get_order(size));
 }
 
 static dma_addr_t jazz_dma_map_page(struct device *dev, struct page *page,
@@ -608,7 +620,6 @@ const struct dma_map_ops jazz_dma_ops = {
 	.sync_single_for_device	= jazz_dma_sync_single_for_device,
 	.sync_sg_for_cpu	= jazz_dma_sync_sg_for_cpu,
 	.sync_sg_for_device	= jazz_dma_sync_sg_for_device,
-	.dma_supported		= dma_direct_supported,
 	.cache_sync		= arch_dma_cache_sync,
 	.mmap			= dma_common_mmap,
 	.get_sgtable		= dma_common_get_sgtable,