dma-mapping: remove CONFIG_ARCH_NO_COHERENT_DMA_MMAP

CONFIG_ARCH_NO_COHERENT_DMA_MMAP is now functionally identical to
!CONFIG_MMU, so remove the separate symbol.  The only difference is that
arm did not set it for !CONFIG_MMU, but arm uses a separate dma mapping
implementation including its own mmap method, which is handled by moving
the CONFIG_MMU check in dma_can_mmap so that is only applies to the
dma-direct case, just as the other ifdefs for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	# m68k

diff --git a/arch/Kconfig b/arch/Kconfig
index a7b57dd..ec28342 100644 (file)
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -790,9 +790,6 @@ config COMPAT_32BIT_TIME
          This is relevant on all 32-bit architectures, and 64-bit architectures
          as part of compat syscall handling.
 
-config ARCH_NO_COHERENT_DMA_MMAP
-       bool
-
 config ARCH_NO_PREEMPT
        bool
 

diff --git a/arch/c6x/Kconfig b/arch/c6x/Kconfig
index b4fb61c..e65e8d8 100644 (file)
--- a/arch/c6x/Kconfig
+++ b/arch/c6x/Kconfig
@@ -20,7 +20,6 @@ config C6X
        select OF_EARLY_FLATTREE
        select GENERIC_CLOCKEVENTS
        select MODULES_USE_ELF_RELA
-       select ARCH_NO_COHERENT_DMA_MMAP
        select MMU_GATHER_NO_RANGE if MMU
 
 config MMU

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index a9e5643..9355998 100644 (file)
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -7,7 +7,6 @@ config M68K
        select ARCH_HAS_DMA_PREP_COHERENT if HAS_DMA && MMU && !COLDFIRE
        select ARCH_HAS_SYNC_DMA_FOR_DEVICE if HAS_DMA
        select ARCH_MIGHT_HAVE_PC_PARPORT if ISA
-       select ARCH_NO_COHERENT_DMA_MMAP if !MMU
        select ARCH_NO_PREEMPT if !COLDFIRE
        select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
        select DMA_DIRECT_REMAP if HAS_DMA && MMU && !COLDFIRE

diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index d411de0..632c947 100644 (file)
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -9,7 +9,6 @@ config MICROBLAZE
        select ARCH_HAS_SYNC_DMA_FOR_CPU
        select ARCH_HAS_SYNC_DMA_FOR_DEVICE
        select ARCH_MIGHT_HAVE_PC_PARPORT
-       select ARCH_NO_COHERENT_DMA_MMAP if !MMU
        select ARCH_WANT_IPC_PARSE_VERSION
        select BUILDTIME_EXTABLE_SORT
        select TIMER_OF

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 6b1b594..f356ee6 100644 (file)
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -5,7 +5,6 @@ config SUPERH
        select ARCH_HAS_PTE_SPECIAL
        select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
        select ARCH_MIGHT_HAVE_PC_PARPORT
-       select ARCH_NO_COHERENT_DMA_MMAP if !MMU
        select HAVE_PATA_PLATFORM
        select CLKDEV_LOOKUP
        select DMA_DECLARE_COHERENT

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index ebc135b..70653ae 100644 (file)
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -5,7 +5,6 @@ config XTENSA
        select ARCH_HAS_BINFMT_FLAT if !MMU
        select ARCH_HAS_SYNC_DMA_FOR_CPU
        select ARCH_HAS_SYNC_DMA_FOR_DEVICE
-       select ARCH_NO_COHERENT_DMA_MMAP if !MMU
        select ARCH_USE_QUEUED_RWLOCKS
        select ARCH_USE_QUEUED_SPINLOCKS
        select ARCH_WANT_FRAME_POINTERS

diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 18ba1ac..285de5f 100644 (file)
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -188,7 +188,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
                void *cpu_addr, dma_addr_t dma_addr, size_t size,
                unsigned long attrs)
 {
-#ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
+#ifdef CONFIG_MMU
        unsigned long user_count = vma_pages(vma);
        unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
        unsigned long off = vma->vm_pgoff;
@@ -219,7 +219,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
                        user_count << PAGE_SHIFT, vma->vm_page_prot);
 #else
        return -ENXIO;
-#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
+#endif /* CONFIG_MMU */
 }
 
 /**
@@ -233,12 +233,10 @@ bool dma_can_mmap(struct device *dev)
 {
        const struct dma_map_ops *ops = get_dma_ops(dev);
 
-       if (IS_ENABLED(CONFIG_ARCH_NO_COHERENT_DMA_MMAP))
-               return false;
-
        if (dma_is_direct(ops)) {
-               return dev_is_dma_coherent(dev) ||
-                       IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN);
+               return IS_ENABLED(CONFIG_MMU) &&
+                      (dev_is_dma_coherent(dev) ||
+                       IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN));
        }
 
        return ops->mmap != NULL;