arm64: replace ZONE_DMA with ZONE_DMA32

arm64 uses ZONE_DMA for allocations below 32-bits.  These days we
name the zone for that ZONE_DMA32, which will allow to use the
dma-direct and generic swiotlb code as-is, so rename it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

arch/arm64/Kconfig

@@ -227,7 +227,7 @@ config GENERIC_CSUM
 config GENERIC_CALIBRATE_DELAY
 	def_bool y
 
-config ZONE_DMA
+config ZONE_DMA32
 	def_bool y
 
 config HAVE_GENERIC_GUP

arch/arm64/mm/dma-mapping.c

@@ -95,9 +95,9 @@ static void *__dma_alloc_coherent(struct device *dev, size_t size,
 				  dma_addr_t *dma_handle, gfp_t flags,
 				  unsigned long attrs)
 {
-	if (IS_ENABLED(CONFIG_ZONE_DMA) &&
+	if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
 	    dev->coherent_dma_mask <= DMA_BIT_MASK(32))
-		flags |= GFP_DMA;
+		flags |= GFP_DMA32;
 	if (dev_get_cma_area(dev) && gfpflags_allow_blocking(flags)) {
 		struct page *page;
 		void *addr;
@@ -397,7 +397,7 @@ static int __init atomic_pool_init(void)
 		page = dma_alloc_from_contiguous(NULL, nr_pages,
 						 pool_size_order, GFP_KERNEL);
 	else
-		page = alloc_pages(GFP_DMA, pool_size_order);
+		page = alloc_pages(GFP_DMA32, pool_size_order);
 
 	if (page) {
 		int ret;

arch/arm64/mm/init.c

@@ -217,7 +217,7 @@ static void __init reserve_elfcorehdr(void)
 }
 #endif /* CONFIG_CRASH_DUMP */
 /*
- * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
+ * Return the maximum physical address for ZONE_DMA32 (DMA_BIT_MASK(32)). It
  * currently assumes that for memory starting above 4G, 32-bit devices will
  * use a DMA offset.
  */
@@ -233,8 +233,8 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
 {
 	unsigned long max_zone_pfns[MAX_NR_ZONES]  = {0};
 
-	if (IS_ENABLED(CONFIG_ZONE_DMA))
-		max_zone_pfns[ZONE_DMA] = PFN_DOWN(max_zone_dma_phys());
+	if (IS_ENABLED(CONFIG_ZONE_DMA32))
+		max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys());
 	max_zone_pfns[ZONE_NORMAL] = max;
 
 	free_area_init_nodes(max_zone_pfns);
@@ -251,9 +251,9 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
 	memset(zone_size, 0, sizeof(zone_size));
 
 	/* 4GB maximum for 32-bit only capable devices */
-#ifdef CONFIG_ZONE_DMA
+#ifdef CONFIG_ZONE_DMA32
 	max_dma = PFN_DOWN(arm64_dma_phys_limit);
-	zone_size[ZONE_DMA] = max_dma - min;
+	zone_size[ZONE_DMA32] = max_dma - min;
 #endif
 	zone_size[ZONE_NORMAL] = max - max_dma;
 
@@ -266,10 +266,10 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
 		if (start >= max)
 			continue;
 
-#ifdef CONFIG_ZONE_DMA
+#ifdef CONFIG_ZONE_DMA32
 		if (start < max_dma) {
 			unsigned long dma_end = min(end, max_dma);
-			zhole_size[ZONE_DMA] -= dma_end - start;
+			zhole_size[ZONE_DMA32] -= dma_end - start;
 		}
 #endif
 		if (end > max_dma) {
@@ -467,7 +467,7 @@ void __init arm64_memblock_init(void)
 	early_init_fdt_scan_reserved_mem();
 
 	/* 4GB maximum for 32-bit only capable devices */
-	if (IS_ENABLED(CONFIG_ZONE_DMA))
+	if (IS_ENABLED(CONFIG_ZONE_DMA32))
 		arm64_dma_phys_limit = max_zone_dma_phys();
 	else
 		arm64_dma_phys_limit = PHYS_MASK + 1;