dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code

Only call into arch_dma_alloc if we require an uncached mapping,
and remove the parisc code manually doing normal cached
DMA_ATTR_NON_CONSISTENT allocations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Helge Deller <deller@gmx.de> # parisc

arch/parisc/kernel/pci-dma.c

@@ -394,17 +394,20 @@ pcxl_dma_init(void)
 
 __initcall(pcxl_dma_init);
 
-static void *pcxl_dma_alloc(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
+void *arch_dma_alloc(struct device *dev, size_t size,
+		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	unsigned long vaddr;
 	unsigned long paddr;
 	int order;
 
+	if (boot_cpu_data.cpu_type != pcxl2 && boot_cpu_data.cpu_type != pcxl)
+		return NULL;
+
 	order = get_order(size);
 	size = 1 << (order + PAGE_SHIFT);
 	vaddr = pcxl_alloc_range(size);
-	paddr = __get_free_pages(flag | __GFP_ZERO, order);
+	paddr = __get_free_pages(gfp | __GFP_ZERO, order);
 	flush_kernel_dcache_range(paddr, size);
 	paddr = __pa(paddr);
 	map_uncached_pages(vaddr, size, paddr);
@@ -421,44 +424,19 @@ static void *pcxl_dma_alloc(struct device *dev, size_t size,
 	return (void *)vaddr;
 }
 
-static void *pcx_dma_alloc(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
-{
-	void *addr;
-
-	if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0)
-		return NULL;
-
-	addr = (void *)__get_free_pages(flag | __GFP_ZERO, get_order(size));
-	if (addr)
-		*dma_handle = (dma_addr_t)virt_to_phys(addr);
-
-	return addr;
-}
-
-void *arch_dma_alloc(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
-{
-
-	if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl)
-		return pcxl_dma_alloc(dev, size, dma_handle, gfp, attrs);
-	else
-		return pcx_dma_alloc(dev, size, dma_handle, gfp, attrs);
-}
-
 void arch_dma_free(struct device *dev, size_t size, void *vaddr,
 		dma_addr_t dma_handle, unsigned long attrs)
 {
 	int order = get_order(size);
 
-	if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
+	WARN_ON_ONCE(boot_cpu_data.cpu_type != pcxl2 &&
+		     boot_cpu_data.cpu_type != pcxl);
+
 	size = 1 << (order + PAGE_SHIFT);
 	unmap_uncached_pages((unsigned long)vaddr, size);
 	pcxl_free_range((unsigned long)vaddr, size);
 
-		vaddr = __va(dma_handle);
-	}
-	free_pages((unsigned long)vaddr, get_order(size));
+	free_pages((unsigned long)__va(dma_handle), order);
 }
 
 void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,

kernel/dma/direct.c

@@ -191,7 +191,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
-	    !dev_is_dma_coherent(dev))
+	    dma_alloc_need_uncached(dev, attrs))
 		return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
 	return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs);
 }
@@ -200,7 +200,7 @@ void dma_direct_free(struct device *dev, size_t size,
 		void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs)
 {
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
-	    !dev_is_dma_coherent(dev))
+	    dma_alloc_need_uncached(dev, attrs))
 		arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
 	else
 		dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs);