Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - replace the force_dma flag with a dma_configure bus method. (Nipun
   Gupta, although one patch is іncorrectly attributed to me due to a
   git rebase bug)

 - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)

 - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
   right thing for bounce buffering.

 - move dma-debug initialization to common code, and apply a few
   cleanups to the dma-debug code.

 - cleanup the Kconfig mess around swiotlb selection

 - swiotlb comment fixup (Yisheng Xie)

 - a trivial swiotlb fix. (Dan Carpenter)

 - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)

 - add a new generic dma-noncoherent dma_map_ops implementation and use
   it for arc, c6x and nds32.

 - improve scatterlist validity checking in dma-debug. (Robin Murphy)

 - add a struct device quirk to limit the dma-mask to 32-bit due to
   bridge/system issues, and switch x86 to use it instead of a local
   hack for VIA bridges.

 - handle devices without a dma_mask more gracefully in the dma-direct
   code.

* tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits)
  dma-direct: don't crash on device without dma_mask
  nds32: use generic dma_noncoherent_ops
  nds32: implement the unmap_sg DMA operation
  nds32: consolidate DMA cache maintainance routines
  x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag
  x86/pci-dma: remove the explicit nodac and allowdac option
  x86/pci-dma: remove the experimental forcesac boot option
  Documentation/x86: remove a stray reference to pci-nommu.c
  core, dma-direct: add a flag 32-bit dma limits
  dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs
  dma-debug: check scatterlist segments
  c6x: use generic dma_noncoherent_ops
  arc: use generic dma_noncoherent_ops
  arc: fix arc_dma_{map,unmap}_page
  arc: fix arc_dma_sync_sg_for_{cpu,device}
  arc: simplify arc_dma_sync_single_for_{cpu,device}
  dma-mapping: provide a generic dma-noncoherent implementation
  dma-mapping: simplify Kconfig dependencies
  riscv: add swiotlb support
  riscv: only enable ZONE_DMA32 for 64-bit
  ...

Documentation/admin-guide/kernel-parameters.txt

@@ -1705,7 +1705,6 @@
 		nopanic
 		merge
 		nomerge
-		forcesac
 		soft
 		pt		[x86, IA-64]
 		nobypass	[PPC/POWERNV]

Documentation/features/io/dma-api-debug/arch-support.txt

-#
-# Feature name:          dma-api-debug
-#         Kconfig:       HAVE_DMA_API_DEBUG
-#         description:   arch supports DMA debug facilities
-#
-    -----------------------
-    |         arch |status|
-    -----------------------
-    |       alpha: | TODO |
-    |         arc: | TODO |
-    |         arm: |  ok  |
-    |       arm64: |  ok  |
-    |         c6x: |  ok  |
-    |       h8300: | TODO |
-    |     hexagon: | TODO |
-    |        ia64: |  ok  |
-    |        m68k: | TODO |
-    |  microblaze: |  ok  |
-    |        mips: |  ok  |
-    |       nios2: | TODO |
-    |    openrisc: | TODO |
-    |      parisc: | TODO |
-    |     powerpc: |  ok  |
-    |        s390: |  ok  |
-    |          sh: |  ok  |
-    |       sparc: |  ok  |
-    |          um: | TODO |
-    |   unicore32: | TODO |
-    |         x86: |  ok  |
-    |      xtensa: |  ok  |
-    -----------------------

Documentation/x86/x86_64/boot-options.txt

@@ -187,9 +187,9 @@ PCI
 
 IOMMU (input/output memory management unit)
 
- Currently four x86-64 PCI-DMA mapping implementations exist:
+ Multiple x86-64 PCI-DMA mapping implementations exist, for example:
 
-   1. <arch/x86_64/kernel/pci-nommu.c>: use no hardware/software IOMMU at all
+   1. <lib/dma-direct.c>: use no hardware/software IOMMU at all
       (e.g. because you have < 3 GB memory).
       Kernel boot message: "PCI-DMA: Disabling IOMMU"
 
@@ -208,7 +208,7 @@ IOMMU (input/output memory management unit)
       Kernel boot message: "PCI-DMA: Using Calgary IOMMU"
 
  iommu=[<size>][,noagp][,off][,force][,noforce][,leak[=<nr_of_leak_pages>]
-	[,memaper[=<order>]][,merge][,forcesac][,fullflush][,nomerge]
+	[,memaper[=<order>]][,merge][,fullflush][,nomerge]
 	[,noaperture][,calgary]
 
   General iommu options:
@@ -235,14 +235,7 @@ IOMMU (input/output memory management unit)
                        (experimental).
     nomerge            Don't do scatter-gather (SG) merging.
     noaperture         Ask the IOMMU not to touch the aperture for AGP.
-    forcesac           Force single-address cycle (SAC) mode for masks <40bits
-                       (experimental).
     noagp              Don't initialize the AGP driver and use full aperture.
-    allowdac           Allow double-address cycle (DAC) mode, i.e. DMA >4GB.
-                       DAC is used with 32-bit PCI to push a 64-bit address in
-                       two cycles. When off all DMA over >4GB is forced through
-                       an IOMMU or software bounce buffering.
-    nodac              Forbid DAC mode, i.e. DMA >4GB.
     panic              Always panic when IOMMU overflows.
     calgary            Use the Calgary IOMMU if it is available
 

MAINTAINERS

@@ -4330,12 +4330,14 @@ W:	http://git.infradead.org/users/hch/dma-mapping.git
 S:	Supported
 F:	lib/dma-debug.c
 F:	lib/dma-direct.c
+F:	lib/dma-noncoherent.c
 F:	lib/dma-virt.c
 F:	drivers/base/dma-mapping.c
 F:	drivers/base/dma-coherent.c
 F:	include/asm-generic/dma-mapping.h
 F:	include/linux/dma-direct.h
 F:	include/linux/dma-mapping.h
+F:	include/linux/dma-noncoherent.h
 
 DME1737 HARDWARE MONITOR DRIVER
 M:	Juerg Haefliger <juergh@gmail.com>

arch/Kconfig

@@ -278,9 +278,6 @@ config HAVE_CLK
 	  The <linux/clk.h> calls support software clock gating and
 	  thus are a key power management tool on many systems.
 
-config HAVE_DMA_API_DEBUG
-	bool
-
 config HAVE_HW_BREAKPOINT
 	bool
 	depends on PERF_EVENTS

arch/alpha/Kconfig

@@ -10,6 +10,8 @@ config ALPHA
 	select HAVE_OPROFILE
 	select HAVE_PCSPKR_PLATFORM
 	select HAVE_PERF_EVENTS
+	select NEED_DMA_MAP_STATE
+	select NEED_SG_DMA_LENGTH
 	select VIRT_TO_BUS
 	select GENERIC_IRQ_PROBE
 	select AUTO_IRQ_AFFINITY if SMP
@@ -64,15 +66,6 @@ config ZONE_DMA
 	bool
 	default y
 
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool y
-
-config NEED_DMA_MAP_STATE
-       def_bool y
-
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
 config GENERIC_ISA_DMA
 	bool
 	default y
@@ -346,9 +339,6 @@ config PCI_DOMAINS
 config PCI_SYSCALL
 	def_bool PCI
 
-config IOMMU_HELPER
-	def_bool PCI
-
 config ALPHA_NONAME
 	bool
 	depends on ALPHA_BOOK1 || ALPHA_NONAME_CH

arch/alpha/include/asm/pci.h

@@ -56,11 +56,6 @@ struct pci_controller {
 
 /* IOMMU controls.  */
 
-/* The PCI address space does not equal the physical memory address space.
-   The networking and block device layers use this boolean for bounce buffer
-   decisions.  */
-#define PCI_DMA_BUS_IS_PHYS  0
-
 /* TODO: integrate with include/asm-generic/pci.h ? */
 static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
 {

arch/arc/Kconfig

@@ -9,11 +9,15 @@
 config ARC
 	def_bool y
 	select ARC_TIMERS
+	select ARCH_HAS_SYNC_DMA_FOR_CPU
+	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
 	select ARCH_HAS_SG_CHAIN
 	select ARCH_SUPPORTS_ATOMIC_RMW if ARC_HAS_LLSC
 	select BUILDTIME_EXTABLE_SORT
 	select CLONE_BACKWARDS
 	select COMMON_CLK
+	select DMA_NONCOHERENT_OPS
+	select DMA_NONCOHERENT_MMAP
 	select GENERIC_ATOMIC64 if !ISA_ARCV2 || !(ARC_HAS_LL64 && ARC_HAS_LLSC)
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_FIND_FIRST_BIT
@@ -453,16 +457,11 @@ config ARC_HAS_PAE40
 	default n
 	depends on ISA_ARCV2
 	select HIGHMEM
+	select PHYS_ADDR_T_64BIT
 	help
 	  Enable access to physical memory beyond 4G, only supported on
 	  ARC cores with 40 bit Physical Addressing support
 
-config ARCH_PHYS_ADDR_T_64BIT
-	def_bool ARC_HAS_PAE40
-
-config ARCH_DMA_ADDR_T_64BIT
-	bool
-
 config ARC_KVADDR_SIZE
 	int "Kernel Virtual Address Space size (MB)"
 	range 0 512

arch/arc/include/asm/Kbuild

@@ -2,6 +2,7 @@
 generic-y += bugs.h
 generic-y += device.h
 generic-y += div64.h
+generic-y += dma-mapping.h
 generic-y += emergency-restart.h
 generic-y += extable.h
 generic-y += fb.h

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

-/*
- * DMA Mapping glue for ARC
- *
- * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#ifndef ASM_ARC_DMA_MAPPING_H
-#define ASM_ARC_DMA_MAPPING_H
-
-extern const struct dma_map_ops arc_dma_ops;
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	return &arc_dma_ops;
-}
-
-#endif

arch/arc/include/asm/pci.h

@@ -16,12 +16,6 @@
 #define PCIBIOS_MIN_MEM 0x100000
 
 #define pcibios_assign_all_busses()	1
-/*
- * The PCI address space does equal the physical memory address space.
- * The networking and block device layers use this boolean for bounce
- * buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS	1
 
 #endif /* __KERNEL__ */
 

arch/arc/mm/dma.c

@@ -16,13 +16,12 @@
  * The default DMA address == Phy address which is 0x8000_0000 based.
  */
 
-#include <linux/dma-mapping.h>
+#include <linux/dma-noncoherent.h>
 #include <asm/cache.h>
 #include <asm/cacheflush.h>
 
-
-static void *arc_dma_alloc(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t gfp, 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 order = get_order(size);
 	struct page *page;
@@ -89,7 +88,7 @@ static void *arc_dma_alloc(struct device *dev, size_t size,
 	return kvaddr;
 }
 
-static void arc_dma_free(struct device *dev, size_t size, void *vaddr,
+void arch_dma_free(struct device *dev, size_t size, void *vaddr,
 		dma_addr_t dma_handle, unsigned long attrs)
 {
 	phys_addr_t paddr = dma_handle;
@@ -105,9 +104,9 @@ static void arc_dma_free(struct device *dev, size_t size, void *vaddr,
 	__free_pages(page, get_order(size));
 }
 
-static int arc_dma_mmap(struct device *dev, struct vm_area_struct *vma,
-			void *cpu_addr, dma_addr_t dma_addr, size_t size,
-			unsigned long attrs)
+int arch_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+		void *cpu_addr, dma_addr_t dma_addr, size_t size,
+		unsigned long attrs)
 {
 	unsigned long user_count = vma_pages(vma);
 	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
@@ -130,149 +129,14 @@ static int arc_dma_mmap(struct device *dev, struct vm_area_struct *vma,
 	return ret;
 }
 
-/*
- * streaming DMA Mapping API...
- * CPU accesses page via normal paddr, thus needs to explicitly made
- * consistent before each use
- */
-static void _dma_cache_sync(phys_addr_t paddr, size_t size,
-		enum dma_data_direction dir)
+void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
+		size_t size, enum dma_data_direction dir)
 {
-	switch (dir) {
-	case DMA_FROM_DEVICE:
-		dma_cache_inv(paddr, size);
-		break;
-	case DMA_TO_DEVICE:
-		dma_cache_wback(paddr, size);
-		break;
-	case DMA_BIDIRECTIONAL:
-		dma_cache_wback_inv(paddr, size);
-		break;
-	default:
-		pr_err("Invalid DMA dir [%d] for OP @ %pa[p]\n", dir, &paddr);
-	}
+	dma_cache_wback(paddr, size);
 }
 
-/*
- * arc_dma_map_page - map a portion of a page for streaming DMA
- *
- * Ensure that any data held in the cache is appropriately discarded
- * or written back.
- *
- * The device owns this memory once this call has completed.  The CPU
- * can regain ownership by calling dma_unmap_page().
- *
- * Note: while it takes struct page as arg, caller can "abuse" it to pass
- * a region larger than PAGE_SIZE, provided it is physically contiguous
- * and this still works correctly
- */
-static dma_addr_t arc_dma_map_page(struct device *dev, struct page *page,
-		unsigned long offset, size_t size, enum dma_data_direction dir,
-		unsigned long attrs)
+void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
+		size_t size, enum dma_data_direction dir)
 {
-	phys_addr_t paddr = page_to_phys(page) + offset;
-
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		_dma_cache_sync(paddr, size, dir);
-
-	return paddr;
-}
-
-/*
- * arc_dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
- *
- * After this call, reads by the CPU to the buffer are guaranteed to see
- * whatever the device wrote there.
- *
- * Note: historically this routine was not implemented for ARC
- */
-static void arc_dma_unmap_page(struct device *dev, dma_addr_t handle,
-			       size_t size, enum dma_data_direction dir,
-			       unsigned long attrs)
-{
-	phys_addr_t paddr = handle;
-
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		_dma_cache_sync(paddr, size, dir);
+	dma_cache_inv(paddr, size);
 }
-
-static int arc_dma_map_sg(struct device *dev, struct scatterlist *sg,
-	   int nents, enum dma_data_direction dir, unsigned long attrs)
-{
-	struct scatterlist *s;
-	int i;
-
-	for_each_sg(sg, s, nents, i)
-		s->dma_address = dma_map_page(dev, sg_page(s), s->offset,
-					       s->length, dir);
-
-	return nents;
-}
-
-static void arc_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
-			     int nents, enum dma_data_direction dir,
-			     unsigned long attrs)
-{
-	struct scatterlist *s;
-	int i;
-
-	for_each_sg(sg, s, nents, i)
-		arc_dma_unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir,
-				   attrs);
-}
-
-static void arc_dma_sync_single_for_cpu(struct device *dev,
-		dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
-{
-	_dma_cache_sync(dma_handle, size, DMA_FROM_DEVICE);
-}
-
-static void arc_dma_sync_single_for_device(struct device *dev,
-		dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
-{
-	_dma_cache_sync(dma_handle, size, DMA_TO_DEVICE);
-}
-
-static void arc_dma_sync_sg_for_cpu(struct device *dev,
-		struct scatterlist *sglist, int nelems,
-		enum dma_data_direction dir)
-{
-	int i;
-	struct scatterlist *sg;
-
-	for_each_sg(sglist, sg, nelems, i)
-		_dma_cache_sync(sg_phys(sg), sg->length, dir);
-}
-
-static void arc_dma_sync_sg_for_device(struct device *dev,
-		struct scatterlist *sglist, int nelems,
-		enum dma_data_direction dir)
-{
-	int i;
-	struct scatterlist *sg;
-
-	for_each_sg(sglist, sg, nelems, i)
-		_dma_cache_sync(sg_phys(sg), sg->length, dir);
-}
-
-static int arc_dma_supported(struct device *dev, u64 dma_mask)
-{
-	/* Support 32 bit DMA mask exclusively */
-	return dma_mask == DMA_BIT_MASK(32);
-}
-
-const struct dma_map_ops arc_dma_ops = {
-	.alloc			= arc_dma_alloc,
-	.free			= arc_dma_free,
-	.mmap			= arc_dma_mmap,
-	.map_page		= arc_dma_map_page,
-	.unmap_page		= arc_dma_unmap_page,
-	.map_sg			= arc_dma_map_sg,
-	.unmap_sg		= arc_dma_unmap_sg,
-	.sync_single_for_device	= arc_dma_sync_single_for_device,
-	.sync_single_for_cpu	= arc_dma_sync_single_for_cpu,
-	.sync_sg_for_cpu	= arc_dma_sync_sg_for_cpu,
-	.sync_sg_for_device	= arc_dma_sync_sg_for_device,
-	.dma_supported		= arc_dma_supported,
-};
-EXPORT_SYMBOL(arc_dma_ops);

arch/arm/Kconfig

@@ -60,7 +60,6 @@ config ARM
 	select HAVE_CONTEXT_TRACKING
 	select HAVE_C_RECORDMCOUNT
 	select HAVE_DEBUG_KMEMLEAK
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS if MMU
 	select HAVE_DYNAMIC_FTRACE if (!XIP_KERNEL) && !CPU_ENDIAN_BE32 && MMU
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
@@ -96,6 +95,7 @@ config ARM
 	select HAVE_VIRT_CPU_ACCOUNTING_GEN
 	select IRQ_FORCED_THREADING
 	select MODULES_USE_ELF_REL
+	select NEED_DMA_MAP_STATE
 	select NO_BOOTMEM
 	select OF_EARLY_FLATTREE if OF
 	select OF_RESERVED_MEM if OF
@@ -119,9 +119,6 @@ config ARM_HAS_SG_CHAIN
 	select ARCH_HAS_SG_CHAIN
 	bool
 
-config NEED_SG_DMA_LENGTH
-	bool
-
 config ARM_DMA_USE_IOMMU
 	bool
 	select ARM_HAS_SG_CHAIN
@@ -224,9 +221,6 @@ config ARCH_MAY_HAVE_PC_FDC
 config ZONE_DMA
 	bool
 
-config NEED_DMA_MAP_STATE
-       def_bool y
-
 config ARCH_SUPPORTS_UPROBES
 	def_bool y
 
@@ -1778,12 +1772,6 @@ config SECCOMP
 	  and the task is only allowed to execute a few safe syscalls
 	  defined by each seccomp mode.
 
-config SWIOTLB
-	def_bool y
-
-config IOMMU_HELPER
-	def_bool SWIOTLB
-
 config PARAVIRT
 	bool "Enable paravirtualization code"
 	help
@@ -1815,6 +1803,7 @@ config XEN
 	depends on MMU
 	select ARCH_DMA_ADDR_T_64BIT
 	select ARM_PSCI
+	select SWIOTLB
 	select SWIOTLB_XEN
 	select PARAVIRT
 	help

arch/arm/include/asm/pci.h

@@ -19,13 +19,6 @@ static inline int pci_proc_domain(struct pci_bus *bus)
 }
 #endif /* CONFIG_PCI_DOMAINS */
 
-/*
- * The PCI address space does equal the physical memory address space.
- * The networking and block device layers use this boolean for bounce
- * buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS     (1)
-
 #define HAVE_PCI_MMAP
 #define ARCH_GENERIC_PCI_MMAP_RESOURCE
 

arch/arm/kernel/setup.c

@@ -754,7 +754,7 @@ int __init arm_add_memory(u64 start, u64 size)
 	else
 		size -= aligned_start - start;
 
-#ifndef CONFIG_ARCH_PHYS_ADDR_T_64BIT
+#ifndef CONFIG_PHYS_ADDR_T_64BIT
 	if (aligned_start > ULONG_MAX) {
 		pr_crit("Ignoring memory at 0x%08llx outside 32-bit physical address space\n",
 			(long long)start);

arch/arm/mach-axxia/Kconfig

@@ -2,7 +2,6 @@
 config ARCH_AXXIA
 	bool "LSI Axxia platforms"
 	depends on ARCH_MULTI_V7 && ARM_LPAE
-	select ARCH_DMA_ADDR_T_64BIT
 	select ARM_AMBA
 	select ARM_GIC
 	select ARM_TIMER_SP804

arch/arm/mach-bcm/Kconfig

@@ -211,7 +211,6 @@ config ARCH_BRCMSTB
 	select BRCMSTB_L2_IRQ
 	select BCM7120_L2_IRQ
 	select ARCH_HAS_HOLES_MEMORYMODEL
-	select ARCH_DMA_ADDR_T_64BIT if ARM_LPAE
 	select ZONE_DMA if ARM_LPAE
 	select SOC_BRCMSTB
 	select SOC_BUS

arch/arm/mach-exynos/Kconfig

@@ -112,7 +112,6 @@ config SOC_EXYNOS5440
 	bool "SAMSUNG EXYNOS5440"
 	default y
 	depends on ARCH_EXYNOS5
-	select ARCH_DMA_ADDR_T_64BIT if ARM_LPAE
 	select HAVE_ARM_ARCH_TIMER
 	select AUTO_ZRELADDR
 	select PINCTRL_EXYNOS5440

arch/arm/mach-highbank/Kconfig

 config ARCH_HIGHBANK
 	bool "Calxeda ECX-1000/2000 (Highbank/Midway)"
 	depends on ARCH_MULTI_V7
-	select ARCH_DMA_ADDR_T_64BIT if ARM_LPAE
 	select ARCH_HAS_HOLES_MEMORYMODEL
 	select ARCH_SUPPORTS_BIG_ENDIAN
 	select ARM_AMBA

arch/arm/mach-rockchip/Kconfig

@@ -3,7 +3,6 @@ config ARCH_ROCKCHIP
 	depends on ARCH_MULTI_V7
 	select PINCTRL
 	select PINCTRL_ROCKCHIP
-	select ARCH_DMA_ADDR_T_64BIT if ARM_LPAE
 	select ARCH_HAS_RESET_CONTROLLER
 	select ARM_AMBA
 	select ARM_GIC

arch/arm/mach-shmobile/Kconfig

@@ -29,7 +29,6 @@ config ARCH_RMOBILE
 menuconfig ARCH_RENESAS
 	bool "Renesas ARM SoCs"
 	depends on ARCH_MULTI_V7 && MMU
-	select ARCH_DMA_ADDR_T_64BIT if ARM_LPAE
 	select ARCH_SHMOBILE
 	select ARM_GIC
 	select GPIOLIB

arch/arm/mach-tegra/Kconfig

@@ -15,6 +15,5 @@ menuconfig ARCH_TEGRA
 	select RESET_CONTROLLER
 	select SOC_BUS
 	select ZONE_DMA if ARM_LPAE
-	select ARCH_DMA_ADDR_T_64BIT if ARM_LPAE
 	help
 	  This enables support for NVIDIA Tegra based systems.

arch/arm/mm/Kconfig

@@ -661,6 +661,7 @@ config ARM_LPAE
 	bool "Support for the Large Physical Address Extension"
 	depends on MMU && CPU_32v7 && !CPU_32v6 && !CPU_32v5 && \
 		!CPU_32v4 && !CPU_32v3
+	select PHYS_ADDR_T_64BIT
 	help
 	  Say Y if you have an ARMv7 processor supporting the LPAE page
 	  table format and you would like to access memory beyond the
@@ -673,12 +674,6 @@ config ARM_PV_FIXUP
 	def_bool y
 	depends on ARM_LPAE && ARM_PATCH_PHYS_VIRT && ARCH_KEYSTONE
 
-config ARCH_PHYS_ADDR_T_64BIT
-	def_bool ARM_LPAE
-
-config ARCH_DMA_ADDR_T_64BIT
-	bool
-
 config ARM_THUMB
 	bool "Support Thumb user binaries" if !CPU_THUMBONLY && EXPERT
 	depends on CPU_THUMB_CAPABLE

arch/arm/mm/dma-mapping-nommu.c

@@ -241,12 +241,3 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 void arch_teardown_dma_ops(struct device *dev)
 {
 }
-
-#define PREALLOC_DMA_DEBUG_ENTRIES	4096
-
-static int __init dma_debug_do_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-	return 0;
-}
-core_initcall(dma_debug_do_init);

arch/arm/mm/dma-mapping.c

@@ -1151,15 +1151,6 @@ int arm_dma_supported(struct device *dev, u64 mask)
 	return __dma_supported(dev, mask, false);
 }
 
-#define PREALLOC_DMA_DEBUG_ENTRIES	4096
-
-static int __init dma_debug_do_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-	return 0;
-}
-core_initcall(dma_debug_do_init);
-
 #ifdef CONFIG_ARM_DMA_USE_IOMMU
 
 static int __dma_info_to_prot(enum dma_data_direction dir, unsigned long attrs)

arch/arm64/Kconfig

@@ -105,7 +105,6 @@ config ARM64
 	select HAVE_CONTEXT_TRACKING
 	select HAVE_DEBUG_BUGVERBOSE
 	select HAVE_DEBUG_KMEMLEAK
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_EFFICIENT_UNALIGNED_ACCESS
@@ -133,6 +132,8 @@ config ARM64
 	select IRQ_FORCED_THREADING
 	select MODULES_USE_ELF_RELA
 	select MULTI_IRQ_HANDLER
+	select NEED_DMA_MAP_STATE
+	select NEED_SG_DMA_LENGTH
 	select NO_BOOTMEM
 	select OF
 	select OF_EARLY_FLATTREE
@@ -142,6 +143,7 @@ config ARM64
 	select POWER_SUPPLY
 	select REFCOUNT_FULL
 	select SPARSE_IRQ
+	select SWIOTLB
 	select SYSCTL_EXCEPTION_TRACE
 	select THREAD_INFO_IN_TASK
 	help
@@ -150,9 +152,6 @@ config ARM64
 config 64BIT
 	def_bool y
 
-config ARCH_PHYS_ADDR_T_64BIT
-	def_bool y
-
 config MMU
 	def_bool y
 
@@ -237,24 +236,9 @@ config ZONE_DMA32
 config HAVE_GENERIC_GUP
 	def_bool y
 
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool y
-
-config NEED_DMA_MAP_STATE
-	def_bool y
-
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
 config SMP
 	def_bool y
 
-config SWIOTLB
-	def_bool y
-
-config IOMMU_HELPER
-	def_bool SWIOTLB
-
 config KERNEL_MODE_NEON
 	def_bool y
 

arch/arm64/include/asm/pci.h

@@ -18,11 +18,6 @@
 #define pcibios_assign_all_busses() \
 	(pci_has_flag(PCI_REASSIGN_ALL_BUS))
 
-/*
- * PCI address space differs from physical memory address space
- */
-#define PCI_DMA_BUS_IS_PHYS	(0)
-
 #define ARCH_GENERIC_PCI_MMAP_RESOURCE	1
 
 extern int isa_dma_bridge_buggy;

arch/arm64/mm/dma-mapping.c

@@ -508,16 +508,6 @@ static int __init arm64_dma_init(void)
 }
 arch_initcall(arm64_dma_init);
 
-#define PREALLOC_DMA_DEBUG_ENTRIES	4096
-
-static int __init dma_debug_do_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-	return 0;
-}
-fs_initcall(dma_debug_do_init);
-
-
 #ifdef CONFIG_IOMMU_DMA
 #include <linux/dma-iommu.h>
 #include <linux/platform_device.h>

arch/c6x/Kconfig

@@ -6,11 +6,13 @@
 
 config C6X
 	def_bool y
+	select ARCH_HAS_SYNC_DMA_FOR_CPU
+	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
 	select CLKDEV_LOOKUP
+	select DMA_NONCOHERENT_OPS
 	select GENERIC_ATOMIC64
 	select GENERIC_IRQ_SHOW
 	select HAVE_ARCH_TRACEHOOK
-	select HAVE_DMA_API_DEBUG
 	select HAVE_MEMBLOCK
 	select SPARSE_IRQ
 	select IRQ_DOMAIN

arch/c6x/include/asm/Kbuild

@@ -5,6 +5,7 @@ generic-y += current.h
 generic-y += device.h
 generic-y += div64.h
 generic-y += dma.h
+generic-y += dma-mapping.h
 generic-y += emergency-restart.h
 generic-y += exec.h
 generic-y += extable.h

arch/c6x/include/asm/dma-mapping.h

-/*
- *  Port on Texas Instruments TMS320C6x architecture
- *
- *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
- *  Author: Aurelien Jacquiot <aurelien.jacquiot@ti.com>
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License version 2 as
- *  published by the Free Software Foundation.
- *
- */
-#ifndef _ASM_C6X_DMA_MAPPING_H
-#define _ASM_C6X_DMA_MAPPING_H
-
-extern const struct dma_map_ops c6x_dma_ops;
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	return &c6x_dma_ops;
-}
-
-extern void coherent_mem_init(u32 start, u32 size);
-void *c6x_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
-		gfp_t gfp, unsigned long attrs);
-void c6x_dma_free(struct device *dev, size_t size, void *vaddr,
-		dma_addr_t dma_handle, unsigned long attrs);
-
-#endif	/* _ASM_C6X_DMA_MAPPING_H */

arch/c6x/include/asm/setup.h

@@ -28,5 +28,7 @@ extern unsigned char c6x_fuse_mac[6];
 extern void machine_init(unsigned long dt_ptr);
 extern void time_init(void);
 
+extern void coherent_mem_init(u32 start, u32 size);
+
 #endif /* !__ASSEMBLY__ */
 #endif /* _ASM_C6X_SETUP_H */

arch/c6x/kernel/Makefile

@@ -8,6 +8,6 @@ extra-y := head.o vmlinux.lds
 obj-y := process.o traps.o irq.o signal.o ptrace.o
 obj-y += setup.o sys_c6x.o time.o devicetree.o
 obj-y += switch_to.o entry.o vectors.o c6x_ksyms.o
-obj-y += soc.o dma.o
+obj-y += soc.o
 
 obj-$(CONFIG_MODULES)           += module.o

arch/c6x/kernel/dma.c

-/*
- *  Copyright (C) 2011 Texas Instruments Incorporated
- *  Author: Mark Salter <msalter@redhat.com>
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License version 2 as
- *  published by the Free Software Foundation.
- */
-#include <linux/module.h>
-#include <linux/dma-mapping.h>
-#include <linux/mm.h>
-#include <linux/mm_types.h>
-#include <linux/scatterlist.h>
-
-#include <asm/cacheflush.h>
-
-static void c6x_dma_sync(dma_addr_t handle, size_t size,
-			 enum dma_data_direction dir)
-{
-	unsigned long paddr = handle;
-
-	BUG_ON(!valid_dma_direction(dir));
-
-	switch (dir) {
-	case DMA_FROM_DEVICE:
-		L2_cache_block_invalidate(paddr, paddr + size);
-		break;
-	case DMA_TO_DEVICE:
-		L2_cache_block_writeback(paddr, paddr + size);
-		break;
-	case DMA_BIDIRECTIONAL:
-		L2_cache_block_writeback_invalidate(paddr, paddr + size);
-		break;
-	default:
-		break;
-	}
-}
-
-static dma_addr_t c6x_dma_map_page(struct device *dev, struct page *page,
-		unsigned long offset, size_t size, enum dma_data_direction dir,
-		unsigned long attrs)
-{
-	dma_addr_t handle = virt_to_phys(page_address(page) + offset);
-
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		c6x_dma_sync(handle, size, dir);
-
-	return handle;
-}
-
-static void c6x_dma_unmap_page(struct device *dev, dma_addr_t handle,
-		size_t size, enum dma_data_direction dir, unsigned long attrs)
-{
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		c6x_dma_sync(handle, size, dir);
-}
-
-static int c6x_dma_map_sg(struct device *dev, struct scatterlist *sglist,
-		int nents, enum dma_data_direction dir, unsigned long attrs)
-{
-	struct scatterlist *sg;
-	int i;
-
-	for_each_sg(sglist, sg, nents, i) {
-		sg->dma_address = sg_phys(sg);
-		if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-			c6x_dma_sync(sg->dma_address, sg->length, dir);
-	}
-
-	return nents;
-}
-
-static void c6x_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
-		  int nents, enum dma_data_direction dir, unsigned long attrs)
-{
-	struct scatterlist *sg;
-	int i;
-
-	if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
-		return;
-
-	for_each_sg(sglist, sg, nents, i)
-		c6x_dma_sync(sg_dma_address(sg), sg->length, dir);
-}
-
-static void c6x_dma_sync_single_for_cpu(struct device *dev, dma_addr_t handle,
-		size_t size, enum dma_data_direction dir)
-{
-	c6x_dma_sync(handle, size, dir);
-
-}
-
-static void c6x_dma_sync_single_for_device(struct device *dev,
-		dma_addr_t handle, size_t size, enum dma_data_direction dir)
-{
-	c6x_dma_sync(handle, size, dir);
-
-}
-
-static void c6x_dma_sync_sg_for_cpu(struct device *dev,
-		struct scatterlist *sglist, int nents,
-		enum dma_data_direction dir)
-{
-	struct scatterlist *sg;
-	int i;
-
-	for_each_sg(sglist, sg, nents, i)
-		c6x_dma_sync_single_for_cpu(dev, sg_dma_address(sg),
-					sg->length, dir);
-
-}
-
-static void c6x_dma_sync_sg_for_device(struct device *dev,
-		struct scatterlist *sglist, int nents,
-		enum dma_data_direction dir)
-{
-	struct scatterlist *sg;
-	int i;
-
-	for_each_sg(sglist, sg, nents, i)
-		c6x_dma_sync_single_for_device(dev, sg_dma_address(sg),
-					   sg->length, dir);
-
-}
-
-const struct dma_map_ops c6x_dma_ops = {
-	.alloc			= c6x_dma_alloc,
-	.free			= c6x_dma_free,
-	.map_page		= c6x_dma_map_page,
-	.unmap_page		= c6x_dma_unmap_page,
-	.map_sg			= c6x_dma_map_sg,
-	.unmap_sg		= c6x_dma_unmap_sg,
-	.sync_single_for_device	= c6x_dma_sync_single_for_device,
-	.sync_single_for_cpu	= c6x_dma_sync_single_for_cpu,
-	.sync_sg_for_device	= c6x_dma_sync_sg_for_device,
-	.sync_sg_for_cpu	= c6x_dma_sync_sg_for_cpu,
-};
-EXPORT_SYMBOL(c6x_dma_ops);
-
-/* Number of entries preallocated for DMA-API debugging */
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-
-static int __init dma_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-
-	return 0;
-}
-fs_initcall(dma_init);

arch/c6x/mm/dma-coherent.c

@@ -19,10 +19,12 @@
 #include <linux/bitops.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
-#include <linux/dma-mapping.h>
+#include <linux/dma-noncoherent.h>
 #include <linux/memblock.h>
 
+#include <asm/cacheflush.h>
 #include <asm/page.h>
+#include <asm/setup.h>
 
 /*
  * DMA coherent memory management, can be redefined using the memdma=
@@ -73,7 +75,7 @@ static void __free_dma_pages(u32 addr, int order)
  * Allocate DMA coherent memory space and return both the kernel
  * virtual and DMA address for that space.
  */
-void *c6x_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
+void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 		gfp_t gfp, unsigned long attrs)
 {
 	u32 paddr;
@@ -98,7 +100,7 @@ void *c6x_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 /*
  * Free DMA coherent memory as defined by the above mapping.
  */
-void c6x_dma_free(struct device *dev, size_t size, void *vaddr,
+void arch_dma_free(struct device *dev, size_t size, void *vaddr,
 		dma_addr_t dma_handle, unsigned long attrs)
 {
 	int order;
@@ -139,3 +141,35 @@ void __init coherent_mem_init(phys_addr_t start, u32 size)
 	dma_bitmap = phys_to_virt(bitmap_phys);
 	memset(dma_bitmap, 0, dma_pages * PAGE_SIZE);
 }
+
+static void c6x_dma_sync(struct device *dev, phys_addr_t paddr, size_t size,
+		enum dma_data_direction dir)
+{
+	BUG_ON(!valid_dma_direction(dir));
+
+	switch (dir) {
+	case DMA_FROM_DEVICE:
+		L2_cache_block_invalidate(paddr, paddr + size);
+		break;
+	case DMA_TO_DEVICE:
+		L2_cache_block_writeback(paddr, paddr + size);
+		break;
+	case DMA_BIDIRECTIONAL:
+		L2_cache_block_writeback_invalidate(paddr, paddr + size);
+		break;
+	default:
+		break;
+	}
+}
+
+void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
+		size_t size, enum dma_data_direction dir)
+{
+	return c6x_dma_sync(dev, paddr, size, dir);
+}
+
+void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
+		size_t size, enum dma_data_direction dir)
+{
+	return c6x_dma_sync(dev, paddr, size, dir);
+}

arch/h8300/include/asm/pci.h

@@ -15,6 +15,4 @@ static inline void pcibios_penalize_isa_irq(int irq, int active)
 	/* We don't do dynamic PCI IRQ allocation */
 }
 
-#define PCI_DMA_BUS_IS_PHYS	(1)
-
 #endif /* _ASM_H8300_PCI_H */

arch/hexagon/Kconfig

@@ -19,6 +19,7 @@ config HEXAGON
 	select GENERIC_IRQ_SHOW
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_TRACEHOOK
+	select NEED_SG_DMA_LENGTH
 	select NO_IOPORT_MAP
 	select GENERIC_IOMAP
 	select GENERIC_SMP_IDLE_THREAD
@@ -63,9 +64,6 @@ config GENERIC_CSUM
 config GENERIC_IRQ_PROBE
 	def_bool y
 
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
 config RWSEM_GENERIC_SPINLOCK
 	def_bool n
 

arch/hexagon/kernel/dma.c

@@ -208,7 +208,6 @@ const struct dma_map_ops hexagon_dma_ops = {
 	.sync_single_for_cpu = hexagon_sync_single_for_cpu,
 	.sync_single_for_device = hexagon_sync_single_for_device,
 	.mapping_error	= hexagon_mapping_error,
-	.is_phys	= 1,
 };
 
 void __init hexagon_dma_init(void)

arch/ia64/Kconfig

@@ -29,7 +29,6 @@ config IA64
 	select HAVE_FUNCTION_TRACER
 	select TTY
 	select HAVE_ARCH_TRACEHOOK
-	select HAVE_DMA_API_DEBUG
 	select HAVE_MEMBLOCK
 	select HAVE_MEMBLOCK_NODE_MAP
 	select HAVE_VIRT_CPU_ACCOUNTING
@@ -54,6 +53,8 @@ config IA64
 	select MODULES_USE_ELF_RELA
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_AUDITSYSCALL
+	select NEED_DMA_MAP_STATE
+	select NEED_SG_DMA_LENGTH
 	default y
 	help
 	  The Itanium Processor Family is Intel's 64-bit successor to
@@ -78,18 +79,6 @@ config MMU
 	bool
 	default y
 
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool y
-
-config NEED_DMA_MAP_STATE
-	def_bool y
-
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
-config SWIOTLB
-       bool
-
 config STACKTRACE_SUPPORT
 	def_bool y
 
@@ -146,7 +135,6 @@ config IA64_GENERIC
 	bool "generic"
 	select NUMA
 	select ACPI_NUMA
-	select DMA_DIRECT_OPS
 	select SWIOTLB
 	select PCI_MSI
 	help
@@ -167,7 +155,6 @@ config IA64_GENERIC
 
 config IA64_DIG
 	bool "DIG-compliant"
-	select DMA_DIRECT_OPS
 	select SWIOTLB
 
 config IA64_DIG_VTD
@@ -183,7 +170,6 @@ config IA64_HP_ZX1
 
 config IA64_HP_ZX1_SWIOTLB
 	bool "HP-zx1/sx1000 with software I/O TLB"
-	select DMA_DIRECT_OPS
 	select SWIOTLB
 	help
 	  Build a kernel that runs on HP zx1 and sx1000 systems even when they
@@ -207,7 +193,6 @@ config IA64_SGI_UV
 	bool "SGI-UV"
 	select NUMA
 	select ACPI_NUMA
-	select DMA_DIRECT_OPS
 	select SWIOTLB
 	help
 	  Selecting this option will optimize the kernel for use on UV based
@@ -218,7 +203,6 @@ config IA64_SGI_UV
 
 config IA64_HP_SIM
 	bool "Ski-simulator"
-	select DMA_DIRECT_OPS
 	select SWIOTLB
 	depends on !PM
 
@@ -613,6 +597,3 @@ source "security/Kconfig"
 source "crypto/Kconfig"
 
 source "lib/Kconfig"
-
-config IOMMU_HELPER
-	def_bool (IA64_HP_ZX1 || IA64_HP_ZX1_SWIOTLB || IA64_GENERIC || SWIOTLB)

arch/ia64/hp/common/sba_iommu.c

@@ -1845,9 +1845,6 @@ static void ioc_init(unsigned long hpa, struct ioc *ioc)
 	ioc_resource_init(ioc);
 	ioc_sac_init(ioc);
 
-	if ((long) ~iovp_mask > (long) ia64_max_iommu_merge_mask)
-		ia64_max_iommu_merge_mask = ~iovp_mask;
-
 	printk(KERN_INFO PFX
 		"%s %d.%d HPA 0x%lx IOVA space %dMb at 0x%lx\n",
 		ioc->name, (ioc->rev >> 4) & 0xF, ioc->rev & 0xF,

arch/ia64/include/asm/pci.h

@@ -30,23 +30,6 @@ struct pci_vector_struct {
 #define PCIBIOS_MIN_IO		0x1000
 #define PCIBIOS_MIN_MEM		0x10000000
 
-/*
- * PCI_DMA_BUS_IS_PHYS should be set to 1 if there is _necessarily_ a direct
- * correspondence between device bus addresses and CPU physical addresses.
- * Platforms with a hardware I/O MMU _must_ turn this off to suppress the
- * bounce buffer handling code in the block and network device layers.
- * Platforms with separate bus address spaces _must_ turn this off and provide
- * a device DMA mapping implementation that takes care of the necessary
- * address translation.
- *
- * For now, the ia64 platforms which may have separate/multiple bus address
- * spaces all have I/O MMUs which support the merging of physically
- * discontiguous buffers, so we can use that as the sole factor to determine
- * the setting of PCI_DMA_BUS_IS_PHYS.
- */
-extern unsigned long ia64_max_iommu_merge_mask;
-#define PCI_DMA_BUS_IS_PHYS	(ia64_max_iommu_merge_mask == ~0UL)
-
 #define HAVE_PCI_MMAP
 #define ARCH_GENERIC_PCI_MMAP_RESOURCE
 #define arch_can_pci_mmap_wc()	1

arch/ia64/kernel/dma-mapping.c

@@ -9,16 +9,6 @@ int iommu_detected __read_mostly;
 const struct dma_map_ops *dma_ops;
 EXPORT_SYMBOL(dma_ops);
 
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-
-static int __init dma_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-
-	return 0;
-}
-fs_initcall(dma_init);
-
 const struct dma_map_ops *dma_get_ops(struct device *dev)
 {
 	return dma_ops;

arch/ia64/kernel/setup.c

@@ -123,18 +123,6 @@ unsigned long ia64_i_cache_stride_shift = ~0;
 #define	CACHE_STRIDE_SHIFT	5
 unsigned long ia64_cache_stride_shift = ~0;
 
-/*
- * The merge_mask variable needs to be set to (max(iommu_page_size(iommu)) - 1).  This
- * mask specifies a mask of address bits that must be 0 in order for two buffers to be
- * mergeable by the I/O MMU (i.e., the end address of the first buffer and the start
- * address of the second buffer must be aligned to (merge_mask+1) in order to be
- * mergeable).  By default, we assume there is no I/O MMU which can merge physically
- * discontiguous buffers, so we set the merge_mask to ~0UL, which corresponds to a iommu
- * page-size of 2^64.
- */
-unsigned long ia64_max_iommu_merge_mask = ~0UL;
-EXPORT_SYMBOL(ia64_max_iommu_merge_mask);
-
 /*
  * We use a special marker for the end of memory and it uses the extra (+1) slot
  */

arch/ia64/sn/kernel/io_common.c

@@ -480,11 +480,6 @@ sn_io_early_init(void)
 	tioca_init_provider();
 	tioce_init_provider();
 
-	/*
-	 * This is needed to avoid bounce limit checks in the blk layer
-	 */
-	ia64_max_iommu_merge_mask = ~PAGE_MASK;
-
 	sn_irq_lh_init();
 	INIT_LIST_HEAD(&sn_sysdata_list);
 	sn_init_cpei_timer();

arch/m68k/include/asm/pci.h

@@ -4,12 +4,6 @@
 
 #include <asm-generic/pci.h>
 
-/* The PCI address space does equal the physical memory
- * address space.  The networking and block device layers use
- * this boolean for bounce buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS	(1)
-
 #define	pcibios_assign_all_busses()	1
 
 #define	PCIBIOS_MIN_IO		0x00000100

arch/microblaze/Kconfig

@@ -19,7 +19,6 @@ config MICROBLAZE
 	select HAVE_ARCH_HASH
 	select HAVE_ARCH_KGDB
 	select HAVE_DEBUG_KMEMLEAK
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_FUNCTION_GRAPH_TRACER

arch/microblaze/include/asm/pci.h

@@ -62,12 +62,6 @@ extern int pci_mmap_legacy_page_range(struct pci_bus *bus,
 
 #define HAVE_PCI_LEGACY	1
 
-/* The PCI address space does equal the physical memory
- * address space (no IOMMU).  The IDE and SCSI device layers use
- * this boolean for bounce buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS     (1)
-
 extern void pcibios_claim_one_bus(struct pci_bus *b);
 
 extern void pcibios_finish_adding_to_bus(struct pci_bus *bus);

arch/microblaze/kernel/dma.c

@@ -184,14 +184,3 @@ const struct dma_map_ops dma_nommu_ops = {
 	.sync_sg_for_device	= dma_nommu_sync_sg_for_device,
 };
 EXPORT_SYMBOL(dma_nommu_ops);
-
-/* Number of entries preallocated for DMA-API debugging */
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-
-static int __init dma_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-
-	return 0;
-}
-fs_initcall(dma_init);

arch/mips/Kconfig

@@ -42,7 +42,6 @@ config MIPS
 	select HAVE_C_RECORDMCOUNT
 	select HAVE_DEBUG_KMEMLEAK
 	select HAVE_DEBUG_STACKOVERFLOW
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_EXIT_THREAD
@@ -132,7 +131,7 @@ config MIPS_GENERIC
 
 config MIPS_ALCHEMY
 	bool "Alchemy processor based machines"
-	select ARCH_PHYS_ADDR_T_64BIT
+	select PHYS_ADDR_T_64BIT
 	select CEVT_R4K
 	select CSRC_R4K
 	select IRQ_MIPS_CPU
@@ -890,7 +889,7 @@ config CAVIUM_OCTEON_SOC
 	bool "Cavium Networks Octeon SoC based boards"
 	select CEVT_R4K
 	select ARCH_HAS_PHYS_TO_DMA
-	select ARCH_PHYS_ADDR_T_64BIT
+	select PHYS_ADDR_T_64BIT
 	select DMA_COHERENT
 	select SYS_SUPPORTS_64BIT_KERNEL
 	select SYS_SUPPORTS_BIG_ENDIAN
@@ -912,6 +911,7 @@ config CAVIUM_OCTEON_SOC
 	select MIPS_NR_CPU_NR_MAP_1024
 	select BUILTIN_DTB
 	select MTD_COMPLEX_MAPPINGS
+	select SWIOTLB
 	select SYS_SUPPORTS_RELOCATABLE
 	help
 	  This option supports all of the Octeon reference boards from Cavium
@@ -936,7 +936,7 @@ config NLM_XLR_BOARD
 	select SWAP_IO_SPACE
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_64BIT_KERNEL
-	select ARCH_PHYS_ADDR_T_64BIT
+	select PHYS_ADDR_T_64BIT
 	select SYS_SUPPORTS_BIG_ENDIAN
 	select SYS_SUPPORTS_HIGHMEM
 	select DMA_COHERENT
@@ -962,7 +962,7 @@ config NLM_XLP_BOARD
 	select HW_HAS_PCI
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_64BIT_KERNEL
-	select ARCH_PHYS_ADDR_T_64BIT
+	select PHYS_ADDR_T_64BIT
 	select GPIOLIB
 	select SYS_SUPPORTS_BIG_ENDIAN
 	select SYS_SUPPORTS_LITTLE_ENDIAN
@@ -1101,9 +1101,6 @@ config GPIO_TXX9
 config FW_CFE
 	bool
 
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool (HIGHMEM && ARCH_PHYS_ADDR_T_64BIT) || 64BIT
-
 config ARCH_SUPPORTS_UPROBES
 	bool
 
@@ -1122,9 +1119,6 @@ config DMA_NONCOHERENT
 	bool
 	select NEED_DMA_MAP_STATE
 
-config NEED_DMA_MAP_STATE
-	bool
-
 config SYS_HAS_EARLY_PRINTK
 	bool
 
@@ -1373,6 +1367,7 @@ config CPU_LOONGSON3
 	select MIPS_PGD_C0_CONTEXT
 	select MIPS_L1_CACHE_SHIFT_6
 	select GPIOLIB
+	select SWIOTLB
 	help
 		The Loongson 3 processor implements the MIPS64R2 instruction
 		set with many extensions.
@@ -1770,7 +1765,7 @@ config CPU_MIPS32_R5_XPA
 	depends on SYS_SUPPORTS_HIGHMEM
 	select XPA
 	select HIGHMEM
-	select ARCH_PHYS_ADDR_T_64BIT
+	select PHYS_ADDR_T_64BIT
 	default n
 	help
 	  Choose this option if you want to enable the Extended Physical
@@ -2402,9 +2397,6 @@ config SB1_PASS_2_1_WORKAROUNDS
 	default y
 
 
-config ARCH_PHYS_ADDR_T_64BIT
-       bool
-
 choice
 	prompt "SmartMIPS or microMIPS ASE support"
 

arch/mips/cavium-octeon/Kconfig

@@ -67,18 +67,6 @@ config CAVIUM_OCTEON_LOCK_L2_MEMCPY
 	help
 	  Lock the kernel's implementation of memcpy() into L2.
 
-config IOMMU_HELPER
-	bool
-
-config NEED_SG_DMA_LENGTH
-	bool
-
-config SWIOTLB
-	def_bool y
-	select DMA_DIRECT_OPS
-	select IOMMU_HELPER
-	select NEED_SG_DMA_LENGTH
-
 config OCTEON_ILM
 	tristate "Module to measure interrupt latency using Octeon CIU Timer"
 	help

arch/mips/include/asm/pci.h

@@ -121,13 +121,6 @@ extern unsigned long PCIBIOS_MIN_MEM;
 #include <linux/string.h>
 #include <asm/io.h>
 
-/*
- * The PCI address space does equal the physical memory address space.
- * The networking and block device layers use this boolean for bounce
- * buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS     (1)
-
 #ifdef CONFIG_PCI_DOMAINS_GENERIC
 static inline int pci_proc_domain(struct pci_bus *bus)
 {

arch/mips/loongson64/Kconfig

@@ -130,21 +130,6 @@ config LOONGSON_UART_BASE
 	default y
 	depends on EARLY_PRINTK || SERIAL_8250
 
-config IOMMU_HELPER
-	bool
-
-config NEED_SG_DMA_LENGTH
-	bool
-
-config SWIOTLB
-	bool "Soft IOMMU Support for All-Memory DMA"
-	default y
-	depends on CPU_LOONGSON3
-	select DMA_DIRECT_OPS
-	select IOMMU_HELPER
-	select NEED_SG_DMA_LENGTH
-	select NEED_DMA_MAP_STATE
-
 config PHYS48_TO_HT40
 	bool
 	default y if CPU_LOONGSON3

arch/mips/mm/dma-default.c

@@ -402,13 +402,3 @@ static const struct dma_map_ops mips_default_dma_map_ops = {
 
 const struct dma_map_ops *mips_dma_map_ops = &mips_default_dma_map_ops;
 EXPORT_SYMBOL(mips_dma_map_ops);
-
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-
-static int __init mips_dma_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-
-	return 0;
-}
-fs_initcall(mips_dma_init);

arch/mips/netlogic/Kconfig

@@ -83,10 +83,4 @@ endif
 config NLM_COMMON
 	bool
 
-config IOMMU_HELPER
-	bool
-
-config NEED_SG_DMA_LENGTH
-	bool
-
 endif

arch/nds32/Kconfig

@@ -5,10 +5,13 @@
 
 config NDS32
         def_bool y
+	select ARCH_HAS_SYNC_DMA_FOR_CPU
+	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
 	select ARCH_WANT_FRAME_POINTERS if FTRACE
 	select CLKSRC_MMIO
 	select CLONE_BACKWARDS
 	select COMMON_CLK
+	select DMA_NONCOHERENT_OPS
 	select GENERIC_ASHLDI3
 	select GENERIC_ASHRDI3
 	select GENERIC_LSHRDI3

arch/nds32/include/asm/Kbuild

@@ -13,6 +13,7 @@ generic-y += cputime.h
 generic-y += device.h
 generic-y += div64.h
 generic-y += dma.h
+generic-y += dma-mapping.h
 generic-y += emergency-restart.h
 generic-y += errno.h
 generic-y += exec.h

arch/nds32/include/asm/dma-mapping.h

-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2005-2017 Andes Technology Corporation
-
-#ifndef ASMNDS32_DMA_MAPPING_H
-#define ASMNDS32_DMA_MAPPING_H
-
-extern struct dma_map_ops nds32_dma_ops;
-
-static inline struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	return &nds32_dma_ops;
-}
-
-#endif

arch/nds32/kernel/dma.c

@@ -3,17 +3,14 @@
 
 #include <linux/types.h>
 #include <linux/mm.h>
-#include <linux/export.h>
 #include <linux/string.h>
-#include <linux/scatterlist.h>
-#include <linux/dma-mapping.h>
+#include <linux/dma-noncoherent.h>
 #include <linux/io.h>
 #include <linux/cache.h>
 #include <linux/highmem.h>
 #include <linux/slab.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
-#include <asm/dma-mapping.h>
 #include <asm/proc-fns.h>
 
 /*
@@ -22,11 +19,6 @@
 static pte_t *consistent_pte;
 static DEFINE_RAW_SPINLOCK(consistent_lock);
 
-enum master_type {
-	FOR_CPU = 0,
-	FOR_DEVICE = 1,
-};
-
 /*
  * VM region handling support.
  *
@@ -124,10 +116,8 @@ static struct arch_vm_region *vm_region_find(struct arch_vm_region *head,
 	return c;
 }
 
-/* FIXME: attrs is not used. */
-static void *nds32_dma_alloc_coherent(struct device *dev, size_t size,
-				      dma_addr_t * handle, gfp_t gfp,
-				      unsigned long attrs)
+void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
+		gfp_t gfp, unsigned long attrs)
 {
 	struct page *page;
 	struct arch_vm_region *c;
@@ -232,8 +222,8 @@ static void *nds32_dma_alloc_coherent(struct device *dev, size_t size,
 	return NULL;
 }
 
-static void nds32_dma_free(struct device *dev, size_t size, void *cpu_addr,
-			   dma_addr_t handle, unsigned long attrs)
+void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,
+		dma_addr_t handle, unsigned long attrs)
 {
 	struct arch_vm_region *c;
 	unsigned long flags, addr;
@@ -333,145 +323,69 @@ static int __init consistent_init(void)
 }
 
 core_initcall(consistent_init);
-static void consistent_sync(void *vaddr, size_t size, int direction, int master_type);
-static dma_addr_t nds32_dma_map_page(struct device *dev, struct page *page,
-				     unsigned long offset, size_t size,
-				     enum dma_data_direction dir,
-				     unsigned long attrs)
-{
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		consistent_sync((void *)(page_address(page) + offset), size, dir, FOR_DEVICE);
-	return page_to_phys(page) + offset;
-}
-
-static void nds32_dma_unmap_page(struct device *dev, dma_addr_t handle,
-				 size_t size, enum dma_data_direction dir,
-				 unsigned long attrs)
-{
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		consistent_sync(phys_to_virt(handle), size, dir, FOR_CPU);
-}
-
-/*
- * Make an area consistent for devices.
- */
-static void consistent_sync(void *vaddr, size_t size, int direction, int master_type)
-{
-	unsigned long start = (unsigned long)vaddr;
-	unsigned long end = start + size;
-
-	if (master_type == FOR_CPU) {
-		switch (direction) {
-		case DMA_TO_DEVICE:
-			break;
-		case DMA_FROM_DEVICE:
-		case DMA_BIDIRECTIONAL:
-			cpu_dma_inval_range(start, end);
-			break;
-		default:
-			BUG();
-		}
-	} else {
-		/* FOR_DEVICE */
-		switch (direction) {
-		case DMA_FROM_DEVICE:
-			break;
-		case DMA_TO_DEVICE:
-		case DMA_BIDIRECTIONAL:
-			cpu_dma_wb_range(start, end);
-			break;
-		default:
-			BUG();
-		}
-	}
-}
 
-static int nds32_dma_map_sg(struct device *dev, struct scatterlist *sg,
-			    int nents, enum dma_data_direction dir,
-			    unsigned long attrs)
+static inline void cache_op(phys_addr_t paddr, size_t size,
+		void (*fn)(unsigned long start, unsigned long end))
 {
-	int i;
+	struct page *page = pfn_to_page(paddr >> PAGE_SHIFT);
+	unsigned offset = paddr & ~PAGE_MASK;
+	size_t left = size;
+	unsigned long start;
 
-	for (i = 0; i < nents; i++, sg++) {
-		void *virt;
-		unsigned long pfn;
-		struct page *page = sg_page(sg);
+	do {
+		size_t len = left;
 
-		sg->dma_address = sg_phys(sg);
-		pfn = page_to_pfn(page) + sg->offset / PAGE_SIZE;
-		page = pfn_to_page(pfn);
 		if (PageHighMem(page)) {
-			virt = kmap_atomic(page);
-			consistent_sync(virt, sg->length, dir, FOR_CPU);
-			kunmap_atomic(virt);
+			void *addr;
+
+			if (offset + len > PAGE_SIZE) {
+				if (offset >= PAGE_SIZE) {
+					page += offset >> PAGE_SHIFT;
+					offset &= ~PAGE_MASK;
+				}
+				len = PAGE_SIZE - offset;
+			}
+
+			addr = kmap_atomic(page);
+			start = (unsigned long)(addr + offset);
+			fn(start, start + len);
+			kunmap_atomic(addr);
 		} else {
-			if (sg->offset > PAGE_SIZE)
-				panic("sg->offset:%08x > PAGE_SIZE\n",
-				      sg->offset);
-			virt = page_address(page) + sg->offset;
-			consistent_sync(virt, sg->length, dir, FOR_CPU);
+			start = (unsigned long)phys_to_virt(paddr);
+			fn(start, start + size);
 		}
-	}
-	return nents;
+		offset = 0;
+		page++;
+		left -= len;
+	} while (left);
 }
 
-static void nds32_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
-			       int nhwentries, enum dma_data_direction dir,
-			       unsigned long attrs)
+void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
+		size_t size, enum dma_data_direction dir)
 {
-}
-
-static void
-nds32_dma_sync_single_for_cpu(struct device *dev, dma_addr_t handle,
-			      size_t size, enum dma_data_direction dir)
-{
-	consistent_sync((void *)phys_to_virt(handle), size, dir, FOR_CPU);
-}
-
-static void
-nds32_dma_sync_single_for_device(struct device *dev, dma_addr_t handle,
-				 size_t size, enum dma_data_direction dir)
-{
-	consistent_sync((void *)phys_to_virt(handle), size, dir, FOR_DEVICE);
-}
-
-static void
-nds32_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nents,
-			  enum dma_data_direction dir)
-{
-	int i;
-
-	for (i = 0; i < nents; i++, sg++) {
-		char *virt =
-		    page_address((struct page *)sg->page_link) + sg->offset;
-		consistent_sync(virt, sg->length, dir, FOR_CPU);
+	switch (dir) {
+	case DMA_FROM_DEVICE:
+		break;
+	case DMA_TO_DEVICE:
+	case DMA_BIDIRECTIONAL:
+		cache_op(paddr, size, cpu_dma_wb_range);
+		break;
+	default:
+		BUG();
 	}
 }
 
-static void
-nds32_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
-			     int nents, enum dma_data_direction dir)
+void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
+		size_t size, enum dma_data_direction dir)
 {
-	int i;
-
-	for (i = 0; i < nents; i++, sg++) {
-		char *virt =
-		    page_address((struct page *)sg->page_link) + sg->offset;
-		consistent_sync(virt, sg->length, dir, FOR_DEVICE);
+	switch (dir) {
+	case DMA_TO_DEVICE:
+		break;
+	case DMA_FROM_DEVICE:
+	case DMA_BIDIRECTIONAL:
+		cache_op(paddr, size, cpu_dma_inval_range);
+		break;
+	default:
+		BUG();
 	}
 }
-
-struct dma_map_ops nds32_dma_ops = {
-	.alloc = nds32_dma_alloc_coherent,
-	.free = nds32_dma_free,
-	.map_page = nds32_dma_map_page,
-	.unmap_page = nds32_dma_unmap_page,
-	.map_sg = nds32_dma_map_sg,
-	.unmap_sg = nds32_dma_unmap_sg,
-	.sync_single_for_device = nds32_dma_sync_single_for_device,
-	.sync_single_for_cpu = nds32_dma_sync_single_for_cpu,
-	.sync_sg_for_cpu = nds32_dma_sync_sg_for_cpu,
-	.sync_sg_for_device = nds32_dma_sync_sg_for_device,
-};
-
-EXPORT_SYMBOL(nds32_dma_ops);

arch/openrisc/kernel/dma.c

@@ -247,14 +247,3 @@ const struct dma_map_ops or1k_dma_map_ops = {
 	.sync_single_for_device = or1k_sync_single_for_device,
 };
 EXPORT_SYMBOL(or1k_dma_map_ops);
-
-/* Number of entries preallocated for DMA-API debugging */
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-
-static int __init dma_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-
-	return 0;
-}
-fs_initcall(dma_init);

arch/parisc/Kconfig

@@ -51,6 +51,8 @@ config PARISC
 	select GENERIC_CLOCKEVENTS
 	select ARCH_NO_COHERENT_DMA_MMAP
 	select CPU_NO_EFFICIENT_FFS
+	select NEED_DMA_MAP_STATE
+	select NEED_SG_DMA_LENGTH
 
 	help
 	  The PA-RISC microprocessor is designed by Hewlett-Packard and used
@@ -111,12 +113,6 @@ config PM
 config STACKTRACE_SUPPORT
 	def_bool y
 
-config NEED_DMA_MAP_STATE
-	def_bool y
-
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
 config ISA_DMA_API
 	bool
 

arch/parisc/include/asm/pci.h

@@ -87,29 +87,6 @@ struct pci_hba_data {
 #define PCI_F_EXTEND		0UL
 #endif /* !CONFIG_64BIT */
 
-/*
- * If the PCI device's view of memory is the same as the CPU's view of memory,
- * PCI_DMA_BUS_IS_PHYS is true.  The networking and block device layers use
- * this boolean for bounce buffer decisions.
- */
-#ifdef CONFIG_PA20
-/* All PA-2.0 machines have an IOMMU. */
-#define PCI_DMA_BUS_IS_PHYS	0
-#define parisc_has_iommu()	do { } while (0)
-#else
-
-#if defined(CONFIG_IOMMU_CCIO) || defined(CONFIG_IOMMU_SBA)
-extern int parisc_bus_is_phys; 	/* in arch/parisc/kernel/setup.c */
-#define PCI_DMA_BUS_IS_PHYS	parisc_bus_is_phys
-#define parisc_has_iommu()	do { parisc_bus_is_phys = 0; } while (0)
-#else
-#define PCI_DMA_BUS_IS_PHYS	1
-#define parisc_has_iommu()	do { } while (0)
-#endif
-
-#endif	/* !CONFIG_PA20 */
-
-
 /*
 ** Most PCI devices (eg Tulip, NCR720) also export the same registers
 ** to both MMIO and I/O port space.  Due to poor performance of I/O Port

arch/parisc/kernel/setup.c

@@ -58,11 +58,6 @@ struct proc_dir_entry * proc_runway_root __read_mostly = NULL;
 struct proc_dir_entry * proc_gsc_root __read_mostly = NULL;
 struct proc_dir_entry * proc_mckinley_root __read_mostly = NULL;
 
-#if !defined(CONFIG_PA20) && (defined(CONFIG_IOMMU_CCIO) || defined(CONFIG_IOMMU_SBA))
-int parisc_bus_is_phys __read_mostly = 1;	/* Assume no IOMMU is present */
-EXPORT_SYMBOL(parisc_bus_is_phys);
-#endif
-
 void __init setup_cmdline(char **cmdline_p)
 {
 	extern unsigned int boot_args[];

arch/powerpc/Kconfig

@@ -13,12 +13,6 @@ config 64BIT
 	bool
 	default y if PPC64
 
-config ARCH_PHYS_ADDR_T_64BIT
-       def_bool PPC64 || PHYS_64BIT
-
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool ARCH_PHYS_ADDR_T_64BIT
-
 config MMU
 	bool
 	default y
@@ -187,7 +181,6 @@ config PPC
 	select HAVE_CONTEXT_TRACKING		if PPC64
 	select HAVE_DEBUG_KMEMLEAK
 	select HAVE_DEBUG_STACKOVERFLOW
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS	if MPROFILE_KERNEL
 	select HAVE_EBPF_JIT			if PPC64
@@ -223,9 +216,11 @@ config PPC
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_VIRT_CPU_ACCOUNTING
 	select HAVE_IRQ_TIME_ACCOUNTING
+	select IOMMU_HELPER			if PPC64
 	select IRQ_DOMAIN
 	select IRQ_FORCED_THREADING
 	select MODULES_USE_ELF_RELA
+	select NEED_SG_DMA_LENGTH
 	select NO_BOOTMEM
 	select OF
 	select OF_EARLY_FLATTREE
@@ -478,19 +473,6 @@ config MPROFILE_KERNEL
 	depends on PPC64 && CPU_LITTLE_ENDIAN
 	def_bool !DISABLE_MPROFILE_KERNEL
 
-config IOMMU_HELPER
-	def_bool PPC64
-
-config SWIOTLB
-	bool "SWIOTLB support"
-	default n
-	select IOMMU_HELPER
-	---help---
-	  Support for IO bounce buffering for systems without an IOMMU.
-	  This allows us to DMA to the full physical address space on
-	  platforms where the size of a physical address is larger
-	  than the bus address.  Not all platforms support this.
-
 config HOTPLUG_CPU
 	bool "Support for enabling/disabling CPUs"
 	depends on SMP && (PPC_PSERIES || \
@@ -913,9 +895,6 @@ config ZONE_DMA
 config NEED_DMA_MAP_STATE
 	def_bool (PPC64 || NOT_COHERENT_CACHE)
 
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
 config GENERIC_ISA_DMA
 	bool
 	depends on ISA_DMA_API

arch/powerpc/include/asm/pci.h

@@ -92,24 +92,6 @@ extern int pci_mmap_legacy_page_range(struct pci_bus *bus,
 
 #define HAVE_PCI_LEGACY	1
 
-#ifdef CONFIG_PPC64
-
-/* The PCI address space does not equal the physical memory address
- * space (we have an IOMMU).  The IDE and SCSI device layers use
- * this boolean for bounce buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS	(0)
-
-#else /* 32-bit */
-
-/* The PCI address space does equal the physical memory
- * address space (no IOMMU).  The IDE and SCSI device layers use
- * this boolean for bounce buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS     (1)
-
-#endif /* CONFIG_PPC64 */
-
 extern void pcibios_claim_one_bus(struct pci_bus *b);
 
 extern void pcibios_finish_adding_to_bus(struct pci_bus *bus);

arch/powerpc/kernel/dma.c

@@ -309,8 +309,6 @@ int dma_set_coherent_mask(struct device *dev, u64 mask)
 }
 EXPORT_SYMBOL(dma_set_coherent_mask);
 
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-
 int dma_set_mask(struct device *dev, u64 dma_mask)
 {
 	if (ppc_md.dma_set_mask)
@@ -361,7 +359,6 @@ EXPORT_SYMBOL_GPL(dma_get_required_mask);
 
 static int __init dma_init(void)
 {
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
 #ifdef CONFIG_PCI
 	dma_debug_add_bus(&pci_bus_type);
 #endif

arch/powerpc/platforms/Kconfig.cputype

@@ -222,6 +222,7 @@ config PTE_64BIT
 config PHYS_64BIT
 	bool 'Large physical address support' if E500 || PPC_86xx
 	depends on (44x || E500 || PPC_86xx) && !PPC_83xx && !PPC_82xx
+	select PHYS_ADDR_T_64BIT
 	---help---
 	  This option enables kernel support for larger than 32-bit physical
 	  addresses.  This feature may not be available on all cores.

arch/riscv/Kconfig

@@ -3,8 +3,16 @@
 # see Documentation/kbuild/kconfig-language.txt.
 #
 
+config 64BIT
+	bool
+
+config 32BIT
+	bool
+
 config RISCV
 	def_bool y
+	# even on 32-bit, physical (and DMA) addresses are > 32-bits
+	select PHYS_ADDR_T_64BIT
 	select OF
 	select OF_EARLY_FLATTREE
 	select OF_IRQ
@@ -22,7 +30,6 @@ config RISCV
 	select GENERIC_ATOMIC64 if !64BIT || !RISCV_ISA_A
 	select HAVE_MEMBLOCK
 	select HAVE_MEMBLOCK_NODE_MAP
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_GENERIC_DMA_COHERENT
 	select IRQ_DOMAIN
@@ -39,16 +46,9 @@ config RISCV
 config MMU
 	def_bool y
 
-# even on 32-bit, physical (and DMA) addresses are > 32-bits
-config ARCH_PHYS_ADDR_T_64BIT
-	def_bool y
-
 config ZONE_DMA32
 	bool
-	default y
-
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool y
+	default y if 64BIT
 
 config PAGE_OFFSET
 	hex
@@ -101,7 +101,6 @@ choice
 
 config ARCH_RV32I
 	bool "RV32I"
-	select CPU_SUPPORTS_32BIT_KERNEL
 	select 32BIT
 	select GENERIC_ASHLDI3
 	select GENERIC_ASHRDI3
@@ -109,13 +108,13 @@ config ARCH_RV32I
 
 config ARCH_RV64I
 	bool "RV64I"
-	select CPU_SUPPORTS_64BIT_KERNEL
 	select 64BIT
 	select HAVE_FUNCTION_TRACER
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS
+	select SWIOTLB
 
 endchoice
 
@@ -171,11 +170,6 @@ config NR_CPUS
 	depends on SMP
 	default "8"
 
-config CPU_SUPPORTS_32BIT_KERNEL
-	bool
-config CPU_SUPPORTS_64BIT_KERNEL
-	bool
-
 choice
 	prompt "CPU Tuning"
 	default TUNE_GENERIC
@@ -202,24 +196,6 @@ endmenu
 
 menu "Kernel type"
 
-choice
-	prompt "Kernel code model"
-	default 64BIT
-
-config 32BIT
-	bool "32-bit kernel"
-	depends on CPU_SUPPORTS_32BIT_KERNEL
-	help
-	  Select this option to build a 32-bit kernel.
-
-config 64BIT
-	bool "64-bit kernel"
-	depends on CPU_SUPPORTS_64BIT_KERNEL
-	help
-	  Select this option to build a 64-bit kernel.
-
-endchoice
-
 source "mm/Kconfig"
 
 source "kernel/Kconfig.preempt"

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

+// SPDX-License-Identifier: GPL-2.0
+#ifndef _RISCV_ASM_DMA_MAPPING_H
+#define _RISCV_ASM_DMA_MAPPING_H 1
+
+#ifdef CONFIG_SWIOTLB
+#include <linux/swiotlb.h>
+static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+{
+	return &swiotlb_dma_ops;
+}
+#else
+#include <asm-generic/dma-mapping.h>
+#endif /* CONFIG_SWIOTLB */
+
+#endif /* _RISCV_ASM_DMA_MAPPING_H */

arch/riscv/include/asm/pci.h

@@ -26,9 +26,6 @@
 /* RISC-V shim does not initialize PCI bus */
 #define pcibios_assign_all_busses() 1
 
-/* We do not have an IOMMU */
-#define PCI_DMA_BUS_IS_PHYS 1
-
 extern int isa_dma_bridge_buggy;
 
 #ifdef CONFIG_PCI

arch/riscv/kernel/setup.c

@@ -29,6 +29,7 @@
 #include <linux/of_fdt.h>
 #include <linux/of_platform.h>
 #include <linux/sched/task.h>
+#include <linux/swiotlb.h>
 
 #include <asm/setup.h>
 #include <asm/sections.h>
@@ -206,6 +207,7 @@ void __init setup_arch(char **cmdline_p)
 	setup_bootmem();
 	paging_init();
 	unflatten_device_tree();
+	swiotlb_init(1);
 
 #ifdef CONFIG_SMP
 	setup_smp();

arch/s390/Kconfig

@@ -35,9 +35,6 @@ config GENERIC_BUG
 config GENERIC_BUG_RELATIVE_POINTERS
 	def_bool y
 
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool y
-
 config GENERIC_LOCKBREAK
 	def_bool y if SMP && PREEMPT
 
@@ -133,7 +130,6 @@ config S390
 	select HAVE_CMPXCHG_LOCAL
 	select HAVE_COPY_THREAD_TLS
 	select HAVE_DEBUG_KMEMLEAK
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
 	select DMA_DIRECT_OPS
 	select HAVE_DYNAMIC_FTRACE
@@ -709,7 +705,11 @@ config QDIO
 menuconfig PCI
 	bool "PCI support"
 	select PCI_MSI
+	select IOMMU_HELPER
 	select IOMMU_SUPPORT
+	select NEED_DMA_MAP_STATE
+	select NEED_SG_DMA_LENGTH
+
 	help
 	  Enable PCI support.
 
@@ -733,15 +733,6 @@ config PCI_DOMAINS
 config HAS_IOMEM
 	def_bool PCI
 
-config IOMMU_HELPER
-	def_bool PCI
-
-config NEED_SG_DMA_LENGTH
-	def_bool PCI
-
-config NEED_DMA_MAP_STATE
-	def_bool PCI
-
 config CHSC_SCH
 	def_tristate m
 	prompt "Support for CHSC subchannels"

arch/s390/include/asm/pci.h

@@ -2,8 +2,6 @@
 #ifndef __ASM_S390_PCI_H
 #define __ASM_S390_PCI_H
 
-/* must be set before including asm-generic/pci.h */
-#define PCI_DMA_BUS_IS_PHYS (0)
 /* must be set before including pci_clp.h */
 #define PCI_BAR_COUNT	6
 

arch/s390/pci/pci_dma.c

@@ -668,15 +668,6 @@ void zpci_dma_exit(void)
 	kmem_cache_destroy(dma_region_table_cache);
 }
 
-#define PREALLOC_DMA_DEBUG_ENTRIES	(1 << 16)
-
-static int __init dma_debug_do_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-	return 0;
-}
-fs_initcall(dma_debug_do_init);
-
 const struct dma_map_ops s390_pci_dma_ops = {
 	.alloc		= s390_dma_alloc,
 	.free		= s390_dma_free,
@@ -685,8 +676,6 @@ const struct dma_map_ops s390_pci_dma_ops = {
 	.map_page	= s390_dma_map_pages,
 	.unmap_page	= s390_dma_unmap_pages,
 	.mapping_error	= s390_mapping_error,
-	/* if we support direct DMA this must be conditional */
-	.is_phys	= 0,
 	/* dma_supported is unconditionally true without a callback */
 };
 EXPORT_SYMBOL_GPL(s390_pci_dma_ops);

arch/sh/Kconfig

@@ -14,7 +14,6 @@ config SUPERH
 	select HAVE_OPROFILE
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_ARCH_TRACEHOOK
-	select HAVE_DMA_API_DEBUG
 	select HAVE_PERF_EVENTS
 	select HAVE_DEBUG_BUGVERBOSE
 	select ARCH_HAVE_CUSTOM_GPIO_H
@@ -51,6 +50,9 @@ config SUPERH
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
+	select NEED_DMA_MAP_STATE
+	select NEED_SG_DMA_LENGTH
+
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
 	  and consumer electronics; it was also used in the Sega Dreamcast
@@ -161,12 +163,6 @@ config DMA_COHERENT
 config DMA_NONCOHERENT
 	def_bool !DMA_COHERENT
 
-config NEED_DMA_MAP_STATE
-	def_bool DMA_NONCOHERENT
-
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
 config PGTABLE_LEVELS
 	default 3 if X2TLB
 	default 2

arch/sh/include/asm/pci.h

@@ -71,12 +71,6 @@ extern unsigned long PCIBIOS_MIN_IO, PCIBIOS_MIN_MEM;
  * SuperH has everything mapped statically like x86.
  */
 
-/* The PCI address space does equal the physical memory
- * address space.  The networking and block device layers use
- * this boolean for bounce buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS	(dma_ops->is_phys)
-
 #ifdef CONFIG_PCI
 /*
  * None of the SH PCI controllers support MWI, it is always treated as a

arch/sh/kernel/dma-nommu.c

@@ -78,7 +78,6 @@ const struct dma_map_ops nommu_dma_ops = {
 	.sync_single_for_device	= nommu_sync_single_for_device,
 	.sync_sg_for_device	= nommu_sync_sg_for_device,
 #endif
-	.is_phys		= 1,
 };
 
 void __init no_iommu_init(void)

arch/sh/mm/consistent.c

@@ -20,18 +20,9 @@
 #include <asm/cacheflush.h>
 #include <asm/addrspace.h>
 
-#define PREALLOC_DMA_DEBUG_ENTRIES	4096
-
 const struct dma_map_ops *dma_ops;
 EXPORT_SYMBOL(dma_ops);
 
-static int __init dma_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-	return 0;
-}
-fs_initcall(dma_init);
-
 void *dma_generic_alloc_coherent(struct device *dev, size_t size,
 				 dma_addr_t *dma_handle, gfp_t gfp,
 				 unsigned long attrs)

arch/sparc/Kconfig

@@ -25,7 +25,6 @@ config SPARC
 	select RTC_CLASS
 	select RTC_DRV_M48T59
 	select RTC_SYSTOHC
-	select HAVE_DMA_API_DEBUG
 	select HAVE_ARCH_JUMP_LABEL if SPARC64
 	select GENERIC_IRQ_SHOW
 	select ARCH_WANT_IPC_PARSE_VERSION
@@ -44,6 +43,8 @@ config SPARC
 	select ARCH_HAS_SG_CHAIN
 	select CPU_NO_EFFICIENT_FFS
 	select LOCKDEP_SMALL if LOCKDEP
+	select NEED_DMA_MAP_STATE
+	select NEED_SG_DMA_LENGTH
 
 config SPARC32
 	def_bool !64BIT
@@ -67,6 +68,7 @@ config SPARC64
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_CONTEXT_TRACKING
 	select HAVE_DEBUG_KMEMLEAK
+	select IOMMU_HELPER
 	select SPARSE_IRQ
 	select RTC_DRV_CMOS
 	select RTC_DRV_BQ4802
@@ -102,14 +104,6 @@ config ARCH_ATU
 	bool
 	default y if SPARC64
 
-config ARCH_DMA_ADDR_T_64BIT
-	bool
-	default y if ARCH_ATU
-
-config IOMMU_HELPER
-	bool
-	default y if SPARC64
-
 config STACKTRACE_SUPPORT
 	bool
 	default y if SPARC64
@@ -146,12 +140,6 @@ config ZONE_DMA
 	bool
 	default y if SPARC32
 
-config NEED_DMA_MAP_STATE
-	def_bool y
-
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
 config GENERIC_ISA_DMA
 	bool
 	default y if SPARC32

arch/sparc/include/asm/iommu_64.h

@@ -17,7 +17,7 @@
 #define IOPTE_WRITE   0x0000000000000002UL
 
 #define IOMMU_NUM_CTXS	4096
-#include <linux/iommu-common.h>
+#include <asm/iommu-common.h>
 
 struct iommu_arena {
 	unsigned long	*map;

arch/sparc/include/asm/pci_32.h

@@ -17,10 +17,6 @@
 
 #define PCI_IRQ_NONE		0xffffffff
 
-/* Dynamic DMA mapping stuff.
- */
-#define PCI_DMA_BUS_IS_PHYS	(0)
-
 #endif /* __KERNEL__ */
 
 #ifndef CONFIG_LEON_PCI

arch/sparc/include/asm/pci_64.h

@@ -17,12 +17,6 @@
 
 #define PCI_IRQ_NONE		0xffffffff
 
-/* The PCI address space does not equal the physical memory
- * address space.  The networking and block device layers use
- * this boolean for bounce buffer decisions.
- */
-#define PCI_DMA_BUS_IS_PHYS	(0)
-
 /* PCI IOMMU mapping bypass support. */
 
 /* PCI 64-bit addressing works for all slots on all controller

arch/sparc/kernel/Makefile

@@ -59,7 +59,7 @@ obj-$(CONFIG_SPARC32)   += leon_pmc.o
 
 obj-$(CONFIG_SPARC64)   += reboot.o
 obj-$(CONFIG_SPARC64)   += sysfs.o
-obj-$(CONFIG_SPARC64)   += iommu.o
+obj-$(CONFIG_SPARC64)   += iommu.o iommu-common.o
 obj-$(CONFIG_SPARC64)   += central.o
 obj-$(CONFIG_SPARC64)   += starfire.o
 obj-$(CONFIG_SPARC64)   += power.o
@@ -74,8 +74,6 @@ obj-$(CONFIG_SPARC64)	+= pcr.o
 obj-$(CONFIG_SPARC64)	+= nmi.o
 obj-$(CONFIG_SPARC64_SMP) += cpumap.o
 
-obj-y                     += dma.o
-
 obj-$(CONFIG_PCIC_PCI)    += pcic.o
 obj-$(CONFIG_LEON_PCI)    += leon_pci.o
 obj-$(CONFIG_SPARC_GRPCI2)+= leon_pci_grpci2.o

arch/sparc/kernel/dma.c

-// SPDX-License-Identifier: GPL-2.0
-#include <linux/kernel.h>
-#include <linux/dma-mapping.h>
-#include <linux/dma-debug.h>
-
-#define PREALLOC_DMA_DEBUG_ENTRIES       (1 << 15)
-
-static int __init dma_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-	return 0;
-}
-fs_initcall(dma_init);

lib/iommu-common.c → arch/sparc/kernel/iommu-common.c

@@ -8,9 +8,9 @@
 #include <linux/bitmap.h>
 #include <linux/bug.h>
 #include <linux/iommu-helper.h>
-#include <linux/iommu-common.h>
 #include <linux/dma-mapping.h>
 #include <linux/hash.h>
+#include <asm/iommu-common.h>
 
 static unsigned long iommu_large_alloc = 15;
 
@@ -93,7 +93,6 @@ void iommu_tbl_pool_init(struct iommu_map_table *iommu,
 	p->hint = p->start;
 	p->end = num_entries;
 }
-EXPORT_SYMBOL(iommu_tbl_pool_init);
 
 unsigned long iommu_tbl_range_alloc(struct device *dev,
 				struct iommu_map_table *iommu,
@@ -224,7 +223,6 @@ unsigned long iommu_tbl_range_alloc(struct device *dev,
 
 	return n;
 }
-EXPORT_SYMBOL(iommu_tbl_range_alloc);
 
 static struct iommu_pool *get_pool(struct iommu_map_table *tbl,
 				   unsigned long entry)
@@ -264,4 +262,3 @@ void iommu_tbl_range_free(struct iommu_map_table *iommu, u64 dma_addr,
 	bitmap_clear(iommu->map, entry, npages);
 	spin_unlock_irqrestore(&(pool->lock), flags);
 }
-EXPORT_SYMBOL(iommu_tbl_range_free);

arch/sparc/kernel/iommu.c

@@ -14,7 +14,7 @@
 #include <linux/errno.h>
 #include <linux/iommu-helper.h>
 #include <linux/bitmap.h>
-#include <linux/iommu-common.h>
+#include <asm/iommu-common.h>
 
 #ifdef CONFIG_PCI
 #include <linux/pci.h>

arch/sparc/kernel/ldc.c

@@ -16,7 +16,7 @@
 #include <linux/list.h>
 #include <linux/init.h>
 #include <linux/bitmap.h>
-#include <linux/iommu-common.h>
+#include <asm/iommu-common.h>
 
 #include <asm/hypervisor.h>
 #include <asm/iommu.h>

arch/sparc/kernel/pci_sun4v.c

@@ -16,7 +16,7 @@
 #include <linux/export.h>
 #include <linux/log2.h>
 #include <linux/of_device.h>
-#include <linux/iommu-common.h>
+#include <asm/iommu-common.h>
 
 #include <asm/iommu.h>
 #include <asm/irq.h>

arch/unicore32/Kconfig

@@ -19,6 +19,8 @@ config UNICORE32
 	select ARCH_WANT_FRAME_POINTERS
 	select GENERIC_IOMAP
 	select MODULES_USE_ELF_REL
+	select NEED_DMA_MAP_STATE
+	select SWIOTLB
 	help
 	  UniCore-32 is 32-bit Instruction Set Architecture,
 	  including a series of low-power-consumption RISC chip
@@ -61,9 +63,6 @@ config ARCH_MAY_HAVE_PC_FDC
 config ZONE_DMA
 	def_bool y
 
-config NEED_DMA_MAP_STATE
-       def_bool y
-
 source "init/Kconfig"
 
 source "kernel/Kconfig.freezer"

arch/unicore32/mm/Kconfig

@@ -39,14 +39,3 @@ config CPU_TLB_SINGLE_ENTRY_DISABLE
 	default y
 	help
 	  Say Y here to disable the TLB single entry operations.
-
-config SWIOTLB
-	def_bool y
-	select DMA_DIRECT_OPS
-
-config IOMMU_HELPER
-	def_bool SWIOTLB
-
-config NEED_SG_DMA_LENGTH
-	def_bool SWIOTLB
-

arch/x86/Kconfig

@@ -28,6 +28,8 @@ config X86_64
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_SOFT_DIRTY
 	select MODULES_USE_ELF_RELA
+	select NEED_DMA_MAP_STATE
+	select SWIOTLB
 	select X86_DEV_DMA_OPS
 	select ARCH_HAS_SYSCALL_WRAPPER
 
@@ -134,7 +136,6 @@ config X86
 	select HAVE_C_RECORDMCOUNT
 	select HAVE_DEBUG_KMEMLEAK
 	select HAVE_DEBUG_STACKOVERFLOW
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS
@@ -184,6 +185,7 @@ config X86
 	select HAVE_UNSTABLE_SCHED_CLOCK
 	select HAVE_USER_RETURN_NOTIFIER
 	select IRQ_FORCED_THREADING
+	select NEED_SG_DMA_LENGTH
 	select PCI_LOCKLESS_CONFIG
 	select PERF_EVENTS
 	select RTC_LIB
@@ -236,13 +238,6 @@ config ARCH_MMAP_RND_COMPAT_BITS_MAX
 config SBUS
 	bool
 
-config NEED_DMA_MAP_STATE
-	def_bool y
-	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
-
-config NEED_SG_DMA_LENGTH
-	def_bool y
-
 config GENERIC_ISA_DMA
 	def_bool y
 	depends on ISA_DMA_API
@@ -875,6 +870,7 @@ config DMI
 
 config GART_IOMMU
 	bool "Old AMD GART IOMMU support"
+	select IOMMU_HELPER
 	select SWIOTLB
 	depends on X86_64 && PCI && AMD_NB
 	---help---
@@ -896,6 +892,7 @@ config GART_IOMMU
 
 config CALGARY_IOMMU
 	bool "IBM Calgary IOMMU support"
+	select IOMMU_HELPER
 	select SWIOTLB
 	depends on X86_64 && PCI
 	---help---
@@ -923,20 +920,6 @@ config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 	  If unsure, say Y.
 
-# need this always selected by IOMMU for the VIA workaround
-config SWIOTLB
-	def_bool y if X86_64
-	---help---
-	  Support for software bounce buffers used on x86-64 systems
-	  which don't have a hardware IOMMU. Using this PCI devices
-	  which can only access 32-bits of memory can be used on systems
-	  with more than 3 GB of memory.
-	  If unsure, say Y.
-
-config IOMMU_HELPER
-	def_bool y
-	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
-
 config MAXSMP
 	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 	depends on X86_64 && SMP && DEBUG_KERNEL
@@ -1458,6 +1441,7 @@ config HIGHMEM
 config X86_PAE
 	bool "PAE (Physical Address Extension) Support"
 	depends on X86_32 && !HIGHMEM4G
+	select PHYS_ADDR_T_64BIT
 	select SWIOTLB
 	---help---
 	  PAE is required for NX support, and furthermore enables
@@ -1485,14 +1469,6 @@ config X86_5LEVEL
 
 	  Say N if unsure.
 
-config ARCH_PHYS_ADDR_T_64BIT
-	def_bool y
-	depends on X86_64 || X86_PAE
-
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool y
-	depends on X86_64 || HIGHMEM64G
-
 config X86_DIRECT_GBPAGES
 	def_bool y
 	depends on X86_64 && !DEBUG_PAGEALLOC

arch/x86/include/asm/dma-mapping.h

@@ -30,10 +30,7 @@ static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
 	return dma_ops;
 }
 
-int arch_dma_supported(struct device *dev, u64 mask);
-#define arch_dma_supported arch_dma_supported
-
-bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp);
+bool arch_dma_alloc_attrs(struct device **dev);
 #define arch_dma_alloc_attrs arch_dma_alloc_attrs
 
 #endif

arch/x86/include/asm/pci.h

@@ -117,9 +117,6 @@ void native_restore_msi_irqs(struct pci_dev *dev);
 #define native_setup_msi_irqs		NULL
 #define native_teardown_msi_irq		NULL
 #endif
-
-#define PCI_DMA_BUS_IS_PHYS (dma_ops->is_phys)
-
 #endif  /* __KERNEL__ */
 
 #ifdef CONFIG_X86_64

arch/x86/kernel/pci-dma.c

@@ -15,13 +15,11 @@
 #include <asm/x86_init.h>
 #include <asm/iommu_table.h>
 
-static int forbid_dac __read_mostly;
+static bool disable_dac_quirk __read_mostly;
 
 const struct dma_map_ops *dma_ops = &dma_direct_ops;
 EXPORT_SYMBOL(dma_ops);
 
-static int iommu_sac_force __read_mostly;
-
 #ifdef CONFIG_IOMMU_DEBUG
 int panic_on_overflow __read_mostly = 1;
 int force_iommu __read_mostly = 1;
@@ -55,9 +53,6 @@ struct device x86_dma_fallback_dev = {
 };
 EXPORT_SYMBOL(x86_dma_fallback_dev);
 
-/* Number of entries preallocated for DMA-API debugging */
-#define PREALLOC_DMA_DEBUG_ENTRIES       65536
-
 void __init pci_iommu_alloc(void)
 {
 	struct iommu_table_entry *p;
@@ -76,7 +71,7 @@ void __init pci_iommu_alloc(void)
 	}
 }
 
-bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp)
+bool arch_dma_alloc_attrs(struct device **dev)
 {
 	if (!*dev)
 		*dev = &x86_dma_fallback_dev;
@@ -125,13 +120,13 @@ static __init int iommu_setup(char *p)
 		if (!strncmp(p, "nomerge", 7))
 			iommu_merge = 0;
 		if (!strncmp(p, "forcesac", 8))
-			iommu_sac_force = 1;
+			pr_warn("forcesac option ignored.\n");
 		if (!strncmp(p, "allowdac", 8))
-			forbid_dac = 0;
+			pr_warn("allowdac option ignored.\n");
 		if (!strncmp(p, "nodac", 5))
-			forbid_dac = 1;
+			pr_warn("nodac option ignored.\n");
 		if (!strncmp(p, "usedac", 6)) {
-			forbid_dac = -1;
+			disable_dac_quirk = true;
 			return 1;
 		}
 #ifdef CONFIG_SWIOTLB
@@ -156,40 +151,9 @@ static __init int iommu_setup(char *p)
 }
 early_param("iommu", iommu_setup);
 
-int arch_dma_supported(struct device *dev, u64 mask)
-{
-#ifdef CONFIG_PCI
-	if (mask > 0xffffffff && forbid_dac > 0) {
-		dev_info(dev, "PCI: Disallowing DAC for device\n");
-		return 0;
-	}
-#endif
-
-	/* Tell the device to use SAC when IOMMU force is on.  This
-	   allows the driver to use cheaper accesses in some cases.
-
-	   Problem with this is that if we overflow the IOMMU area and
-	   return DAC as fallback address the device may not handle it
-	   correctly.
-
-	   As a special case some controllers have a 39bit address
-	   mode that is as efficient as 32bit (aic79xx). Don't force
-	   SAC for these.  Assume all masks <= 40 bits are of this
-	   type. Normally this doesn't make any difference, but gives
-	   more gentle handling of IOMMU overflow. */
-	if (iommu_sac_force && (mask >= DMA_BIT_MASK(40))) {
-		dev_info(dev, "Force SAC with mask %Lx\n", mask);
-		return 0;
-	}
-
-	return 1;
-}
-EXPORT_SYMBOL(arch_dma_supported);
-
 static int __init pci_iommu_init(void)
 {
 	struct iommu_table_entry *p;
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
 
 #ifdef CONFIG_PCI
 	dma_debug_add_bus(&pci_bus_type);
@@ -209,11 +173,17 @@ rootfs_initcall(pci_iommu_init);
 #ifdef CONFIG_PCI
 /* Many VIA bridges seem to corrupt data for DAC. Disable it here */
 
+static int via_no_dac_cb(struct pci_dev *pdev, void *data)
+{
+	pdev->dev.dma_32bit_limit = true;
+	return 0;
+}
+
 static void via_no_dac(struct pci_dev *dev)
 {
-	if (forbid_dac == 0) {
+	if (!disable_dac_quirk) {
 		dev_info(&dev->dev, "disabling DAC on VIA PCI bridge\n");
-		forbid_dac = 1;
+		pci_walk_bus(dev->subordinate, via_no_dac_cb, NULL);
 	}
 }
 DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_VIA, PCI_ANY_ID,

arch/xtensa/Kconfig

@@ -19,7 +19,6 @@ config XTENSA
 	select HAVE_ARCH_KASAN if MMU
 	select HAVE_CC_STACKPROTECTOR
 	select HAVE_DEBUG_KMEMLEAK
-	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_EXIT_THREAD
 	select HAVE_FUNCTION_TRACER

arch/xtensa/include/asm/pci.h

@@ -42,8 +42,6 @@ extern struct pci_controller* pcibios_alloc_controller(void);
  * decisions.
  */
 
-#define PCI_DMA_BUS_IS_PHYS	(1)
-
 /* Tell PCI code what kind of PCI resource mappings we support */
 #define HAVE_PCI_MMAP			1
 #define ARCH_GENERIC_PCI_MMAP_RESOURCE	1

arch/xtensa/kernel/pci-dma.c

@@ -261,12 +261,3 @@ const struct dma_map_ops xtensa_dma_map_ops = {
 	.mapping_error = xtensa_dma_mapping_error,
 };
 EXPORT_SYMBOL(xtensa_dma_map_ops);
-
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-
-static int __init xtensa_dma_init(void)
-{
-	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
-	return 0;
-}
-fs_initcall(xtensa_dma_init);

drivers/amba/bus.c

@@ -20,6 +20,7 @@
 #include <linux/sizes.h>
 #include <linux/limits.h>
 #include <linux/clk/clk-conf.h>
+#include <linux/platform_device.h>
 
 #include <asm/irq.h>
 
@@ -193,14 +194,16 @@ static const struct dev_pm_ops amba_pm = {
 /*
  * Primecells are part of the Advanced Microcontroller Bus Architecture,
  * so we call the bus "amba".
+ * DMA configuration for platform and AMBA bus is same. So here we reuse
+ * platform's DMA config routine.
  */
 struct bus_type amba_bustype = {
 	.name		= "amba",
 	.dev_groups	= amba_dev_groups,
 	.match		= amba_match,
 	.uevent		= amba_uevent,
+	.dma_configure	= platform_dma_configure,
 	.pm		= &amba_pm,
-	.force_dma	= true,
 };
 
 static int __init amba_init(void)

drivers/base/dma-mapping.c

@@ -329,36 +329,13 @@ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
 #endif
 
 /*
- * Common configuration to enable DMA API use for a device
+ * enables DMA API use for a device
  */
-#include <linux/pci.h>
-
 int dma_configure(struct device *dev)
 {
-	struct device *bridge = NULL, *dma_dev = dev;
-	enum dev_dma_attr attr;
-	int ret = 0;
-
-	if (dev_is_pci(dev)) {
-		bridge = pci_get_host_bridge_device(to_pci_dev(dev));
-		dma_dev = bridge;
-		if (IS_ENABLED(CONFIG_OF) && dma_dev->parent &&
-		    dma_dev->parent->of_node)
-			dma_dev = dma_dev->parent;
-	}
-
-	if (dma_dev->of_node) {
-		ret = of_dma_configure(dev, dma_dev->of_node);
-	} else if (has_acpi_companion(dma_dev)) {
-		attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode));
-		if (attr != DEV_DMA_NOT_SUPPORTED)
-			ret = acpi_dma_configure(dev, attr);
-	}
-
-	if (bridge)
-		pci_put_host_bridge_device(bridge);
-
-	return ret;
+	if (dev->bus->dma_configure)
+		return dev->bus->dma_configure(dev);
+	return 0;
 }
 
 void dma_deconfigure(struct device *dev)

drivers/base/platform.c

@@ -1130,6 +1130,22 @@ int platform_pm_restore(struct device *dev)
 
 #endif /* CONFIG_HIBERNATE_CALLBACKS */
 
+int platform_dma_configure(struct device *dev)
+{
+	enum dev_dma_attr attr;
+	int ret = 0;
+
+	if (dev->of_node) {
+		ret = of_dma_configure(dev, dev->of_node, true);
+	} else if (has_acpi_companion(dev)) {
+		attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
+		if (attr != DEV_DMA_NOT_SUPPORTED)
+			ret = acpi_dma_configure(dev, attr);
+	}
+
+	return ret;
+}
+
 static const struct dev_pm_ops platform_dev_pm_ops = {
 	.runtime_suspend = pm_generic_runtime_suspend,
 	.runtime_resume = pm_generic_runtime_resume,
@@ -1141,8 +1157,8 @@ struct bus_type platform_bus_type = {
 	.dev_groups	= platform_dev_groups,
 	.match		= platform_match,
 	.uevent		= platform_uevent,
+	.dma_configure	= platform_dma_configure,
 	.pm		= &platform_dev_pm_ops,
-	.force_dma	= true,
 };
 EXPORT_SYMBOL_GPL(platform_bus_type);