dma-mapping: make the get_required_mask method available unconditionally

This save some duplication for ia64, and makes the interface more
general.  In the long run we want each dma_map_ops instance to fill this
out, but this will take a little more prep work.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/ia64/include/asm/dma-mapping.h

@@ -10,8 +10,6 @@
 #include <linux/scatterlist.h>
 #include <linux/dma-debug.h>
 
-#define ARCH_HAS_DMA_GET_REQUIRED_MASK
-
 extern const struct dma_map_ops *dma_ops;
 extern struct ia64_machine_vector ia64_mv;
 extern void set_iommu_machvec(void);

arch/ia64/include/asm/machvec.h

@@ -44,7 +44,6 @@ typedef void ia64_mv_kernel_launch_event_t(void);
 
 /* DMA-mapping interface: */
 typedef void ia64_mv_dma_init (void);
-typedef u64 ia64_mv_dma_get_required_mask (struct device *);
 typedef const struct dma_map_ops *ia64_mv_dma_get_ops(struct device *);
 
 /*
@@ -127,7 +126,6 @@ extern void machvec_tlb_migrate_finish (struct mm_struct *);
 #  define platform_global_tlb_purge	ia64_mv.global_tlb_purge
 #  define platform_tlb_migrate_finish	ia64_mv.tlb_migrate_finish
 #  define platform_dma_init		ia64_mv.dma_init
-#  define platform_dma_get_required_mask ia64_mv.dma_get_required_mask
 #  define platform_dma_get_ops		ia64_mv.dma_get_ops
 #  define platform_irq_to_vector	ia64_mv.irq_to_vector
 #  define platform_local_vector_to_irq	ia64_mv.local_vector_to_irq
@@ -171,7 +169,6 @@ struct ia64_machine_vector {
 	ia64_mv_global_tlb_purge_t *global_tlb_purge;
 	ia64_mv_tlb_migrate_finish_t *tlb_migrate_finish;
 	ia64_mv_dma_init *dma_init;
-	ia64_mv_dma_get_required_mask *dma_get_required_mask;
 	ia64_mv_dma_get_ops *dma_get_ops;
 	ia64_mv_irq_to_vector *irq_to_vector;
 	ia64_mv_local_vector_to_irq *local_vector_to_irq;
@@ -211,7 +208,6 @@ struct ia64_machine_vector {
 	platform_global_tlb_purge,		\
 	platform_tlb_migrate_finish,		\
 	platform_dma_init,			\
-	platform_dma_get_required_mask,		\
 	platform_dma_get_ops,			\
 	platform_irq_to_vector,			\
 	platform_local_vector_to_irq,		\
@@ -286,9 +282,6 @@ extern const struct dma_map_ops *dma_get_ops(struct device *);
 #ifndef platform_dma_get_ops
 # define platform_dma_get_ops		dma_get_ops
 #endif
-#ifndef platform_dma_get_required_mask
-# define  platform_dma_get_required_mask	ia64_dma_get_required_mask
-#endif
 #ifndef platform_irq_to_vector
 # define platform_irq_to_vector		__ia64_irq_to_vector
 #endif

arch/ia64/include/asm/machvec_init.h

@@ -4,7 +4,6 @@
 
 extern ia64_mv_send_ipi_t ia64_send_ipi;
 extern ia64_mv_global_tlb_purge_t ia64_global_tlb_purge;
-extern ia64_mv_dma_get_required_mask ia64_dma_get_required_mask;
 extern ia64_mv_irq_to_vector __ia64_irq_to_vector;
 extern ia64_mv_local_vector_to_irq __ia64_local_vector_to_irq;
 extern ia64_mv_pci_get_legacy_mem_t ia64_pci_get_legacy_mem;

arch/ia64/include/asm/machvec_sn2.h

@@ -55,7 +55,6 @@ extern ia64_mv_readb_t __sn_readb_relaxed;
 extern ia64_mv_readw_t __sn_readw_relaxed;
 extern ia64_mv_readl_t __sn_readl_relaxed;
 extern ia64_mv_readq_t __sn_readq_relaxed;
-extern ia64_mv_dma_get_required_mask	sn_dma_get_required_mask;
 extern ia64_mv_dma_init			sn_dma_init;
 extern ia64_mv_migrate_t		sn_migrate;
 extern ia64_mv_kernel_launch_event_t	sn_kernel_launch_event;
@@ -100,7 +99,6 @@ extern ia64_mv_pci_fixup_bus_t		sn_pci_fixup_bus;
 #define platform_pci_get_legacy_mem	sn_pci_get_legacy_mem
 #define platform_pci_legacy_read	sn_pci_legacy_read
 #define platform_pci_legacy_write	sn_pci_legacy_write
-#define platform_dma_get_required_mask	sn_dma_get_required_mask
 #define platform_dma_init		sn_dma_init
 #define platform_migrate		sn_migrate
 #define platform_kernel_launch_event    sn_kernel_launch_event

arch/ia64/pci/pci.c

@@ -568,32 +568,6 @@ static void __init set_pci_dfl_cacheline_size(void)
 	pci_dfl_cache_line_size = (1 << cci.pcci_line_size) / 4;
 }
 
-u64 ia64_dma_get_required_mask(struct device *dev)
-{
-	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
-	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
-	u64 mask;
-
-	if (!high_totalram) {
-		/* convert to mask just covering totalram */
-		low_totalram = (1 << (fls(low_totalram) - 1));
-		low_totalram += low_totalram - 1;
-		mask = low_totalram;
-	} else {
-		high_totalram = (1 << (fls(high_totalram) - 1));
-		high_totalram += high_totalram - 1;
-		mask = (((u64)high_totalram) << 32) + 0xffffffff;
-	}
-	return mask;
-}
-EXPORT_SYMBOL_GPL(ia64_dma_get_required_mask);
-
-u64 dma_get_required_mask(struct device *dev)
-{
-	return platform_dma_get_required_mask(dev);
-}
-EXPORT_SYMBOL_GPL(dma_get_required_mask);
-
 static int __init pcibios_init(void)
 {
 	set_pci_dfl_cacheline_size();

arch/ia64/sn/pci/pci_dma.c

@@ -344,11 +344,10 @@ static int sn_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 	return 0;
 }
 
-u64 sn_dma_get_required_mask(struct device *dev)
+static u64 sn_dma_get_required_mask(struct device *dev)
 {
 	return DMA_BIT_MASK(64);
 }
-EXPORT_SYMBOL_GPL(sn_dma_get_required_mask);
 
 char *sn_pci_get_legacy_mem(struct pci_bus *bus)
 {
@@ -473,6 +472,7 @@ static struct dma_map_ops sn_dma_ops = {
 	.sync_sg_for_device	= sn_dma_sync_sg_for_device,
 	.mapping_error		= sn_dma_mapping_error,
 	.dma_supported		= sn_dma_supported,
+	.get_required_mask	= sn_dma_get_required_mask,
 };
 
 void sn_dma_init(void)

drivers/base/platform.c

@@ -1179,8 +1179,7 @@ int __init platform_bus_init(void)
 	return error;
 }
 
-#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
-u64 dma_get_required_mask(struct device *dev)
+static u64 dma_default_get_required_mask(struct device *dev)
 {
 	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
 	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
@@ -1198,6 +1197,16 @@ u64 dma_get_required_mask(struct device *dev)
 	}
 	return mask;
 }
+
+#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
+u64 dma_get_required_mask(struct device *dev)
+{
+	const struct dma_map_ops *ops = get_dma_ops(dev);
+
+	if (ops->get_required_mask)
+		return ops->get_required_mask(dev);
+	return dma_default_get_required_mask(dev);
+}
 EXPORT_SYMBOL_GPL(dma_get_required_mask);
 #endif
 

drivers/pci/controller/vmd.c

@@ -404,12 +404,10 @@ static int vmd_dma_supported(struct device *dev, u64 mask)
 	return vmd_dma_ops(dev)->dma_supported(to_vmd_dev(dev), mask);
 }
 
-#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
 static u64 vmd_get_required_mask(struct device *dev)
 {
 	return vmd_dma_ops(dev)->get_required_mask(to_vmd_dev(dev));
 }
-#endif
 
 static void vmd_teardown_dma_ops(struct vmd_dev *vmd)
 {
@@ -450,9 +448,7 @@ static void vmd_setup_dma_ops(struct vmd_dev *vmd)
 	ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_device);
 	ASSIGN_VMD_DMA_OPS(source, dest, mapping_error);
 	ASSIGN_VMD_DMA_OPS(source, dest, dma_supported);
-#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
 	ASSIGN_VMD_DMA_OPS(source, dest, get_required_mask);
-#endif
 	add_dma_domain(domain);
 }
 #undef ASSIGN_VMD_DMA_OPS

include/linux/dma-mapping.h

@@ -130,9 +130,7 @@ struct dma_map_ops {
 			enum dma_data_direction direction);
 	int (*mapping_error)(struct device *dev, dma_addr_t dma_addr);
 	int (*dma_supported)(struct device *dev, u64 mask);
-#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
 	u64 (*get_required_mask)(struct device *dev);
-#endif
 };
 
 extern const struct dma_map_ops dma_direct_ops;