Merge tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - move the USB special case that bounced DMA through a device bar into
   the USB code instead of handling it in the common DMA code (Laurentiu
   Tudor and Fredrik Noring)

 - don't dip into the global CMA pool for single page allocations
   (Nicolin Chen)

 - fix a crash when allocating memory for the atomic pool failed during
   boot (Florian Fainelli)

 - move support for MIPS-style uncached segments to the common code and
   use that for MIPS and nios2 (me)

 - make support for DMA_ATTR_NON_CONSISTENT and
   DMA_ATTR_NO_KERNEL_MAPPING generic (me)

 - convert nds32 to the generic remapping allocator (me)

* tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping: (29 commits)
  dma-mapping: mark dma_alloc_need_uncached as __always_inline
  MIPS: only select ARCH_HAS_UNCACHED_SEGMENT for non-coherent platforms
  usb: host: Fix excessive alignment restriction for local memory allocations
  lib/genalloc.c: Add algorithm, align and zeroed family of DMA allocators
  nios2: use the generic uncached segment support in dma-direct
  nds32: use the generic remapping allocator for coherent DMA allocations
  arc: use the generic remapping allocator for coherent DMA allocations
  dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code
  dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code
  dma-mapping: add a dma_alloc_need_uncached helper
  openrisc: remove the partial DMA_ATTR_NON_CONSISTENT support
  arc: remove the partial DMA_ATTR_NON_CONSISTENT support
  arm-nommu: remove the partial DMA_ATTR_NON_CONSISTENT support
  ARM: dma-mapping: allow larger DMA mask than supported
  dma-mapping: truncate dma masks to what dma_addr_t can hold
  iommu/dma: Apply dma_{alloc,free}_contiguous functions
  dma-remap: Avoid de-referencing NULL atomic_pool
  MIPS: use the generic uncached segment support in dma-direct
  dma-direct: provide generic support for uncached kernel segments
  au1100fb: fix DMA API abuse
  ...

3 files changed, 16 insertions, 25 deletions

diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
index 26a9c760a98b..44b5da37e8bd 100644
--- a/arch/nios2/Kconfig
+++ b/arch/nios2/Kconfig
@@ -4,6 +4,7 @@ config NIOS2
 	select ARCH_32BIT_OFF_T
 	select ARCH_HAS_SYNC_DMA_FOR_CPU
 	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
+	select ARCH_HAS_UNCACHED_SEGMENT
 	select ARCH_NO_SWAP
 	select TIMER_OF
 	select GENERIC_ATOMIC64
diff --git a/arch/nios2/include/asm/page.h b/arch/nios2/include/asm/page.h
index f1fbdc47bdaf..79fcac61f6ef 100644
--- a/arch/nios2/include/asm/page.h
+++ b/arch/nios2/include/asm/page.h
@@ -101,12 +101,6 @@ static inline bool pfn_valid(unsigned long pfn)
 # define VM_DATA_DEFAULT_FLAGS	(VM_READ | VM_WRITE | \
 				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
 
-# define UNCAC_ADDR(addr)	\
-	((void *)((unsigned)(addr) | CONFIG_NIOS2_IO_REGION_BASE))
-# define CAC_ADDR(addr)		\
-	((void *)(((unsigned)(addr) & ~CONFIG_NIOS2_IO_REGION_BASE) |	\
-		CONFIG_NIOS2_KERNEL_REGION_BASE))
-
 #include <asm-generic/memory_model.h>
 
 #include <asm-generic/getorder.h>
diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c
index 4af9e5b5ba1c..9cb238664584 100644
--- a/arch/nios2/mm/dma-mapping.c
+++ b/arch/nios2/mm/dma-mapping.c
@@ -60,32 +60,28 @@ void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
 	}
 }
 
-void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
-		gfp_t gfp, unsigned long attrs)
+void arch_dma_prep_coherent(struct page *page, size_t size)
 {
-	void *ret;
+	unsigned long start = (unsigned long)page_address(page);
 
-	/* optimized page clearing */
-	gfp |= __GFP_ZERO;
+	flush_dcache_range(start, start + size);
+}
 
-	if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
-		gfp |= GFP_DMA;
+void *uncached_kernel_address(void *ptr)
+{
+	unsigned long addr = (unsigned long)ptr;
 
-	ret = (void *) __get_free_pages(gfp, get_order(size));
-	if (ret != NULL) {
-		*dma_handle = virt_to_phys(ret);
-		flush_dcache_range((unsigned long) ret,
-			(unsigned long) ret + size);
-		ret = UNCAC_ADDR(ret);
-	}
+	addr |= CONFIG_NIOS2_IO_REGION_BASE;
 
-	return ret;
+	return (void *)ptr;
 }
 
-void arch_dma_free(struct device *dev, size_t size, void *vaddr,
-		dma_addr_t dma_handle, unsigned long attrs)
+void *cached_kernel_address(void *ptr)
 {
-	unsigned long addr = (unsigned long) CAC_ADDR((unsigned long) vaddr);
+	unsigned long addr = (unsigned long)ptr;
+
+	addr &= ~CONFIG_NIOS2_IO_REGION_BASE;
+	addr |= CONFIG_NIOS2_KERNEL_REGION_BASE;
 
-	free_pages(addr, get_order(size));
+	return (void *)ptr;
 }