[5/5] dma-mapping: remove ARCH_NO_COHERENT_DMA_MMAP
diff mbox series

Message ID 20190725063401.29904-6-hch@lst.de
State Awaiting Upstream
Headers show
Series
  • [1/5] m68knommu: add a pgprot_noncached stub
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Commit Message

Christoph Hellwig July 25, 2019, 6:34 a.m. UTC
Now that we never use a default ->mmap implementation, and non-coherent
architectures can control the presence of ->mmap support by enabling
ARCH_HAS_DMA_COHERENT_TO_PFN for the dma direct implementation there
is no need for a global config option to control the availability
of dma_common_mmap.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/Kconfig            |  3 ---
 arch/c6x/Kconfig        |  1 -
 arch/m68k/Kconfig       |  1 -
 arch/microblaze/Kconfig |  1 -
 arch/parisc/Kconfig     |  1 -
 arch/sh/Kconfig         |  1 -
 arch/xtensa/Kconfig     |  1 -
 kernel/dma/mapping.c    |  4 ----
 sound/core/pcm_native.c | 10 +---------
 9 files changed, 1 insertion(+), 22 deletions(-)

Comments

Christoph Hellwig Aug. 2, 2019, 7:03 a.m. UTC | #1
Takashi,

any comments on the sounds/ side of this?

On Thu, Jul 25, 2019 at 08:34:01AM +0200, Christoph Hellwig wrote:
> Now that we never use a default ->mmap implementation, and non-coherent
> architectures can control the presence of ->mmap support by enabling
> ARCH_HAS_DMA_COHERENT_TO_PFN for the dma direct implementation there
> is no need for a global config option to control the availability
> of dma_common_mmap.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  arch/Kconfig            |  3 ---
>  arch/c6x/Kconfig        |  1 -
>  arch/m68k/Kconfig       |  1 -
>  arch/microblaze/Kconfig |  1 -
>  arch/parisc/Kconfig     |  1 -
>  arch/sh/Kconfig         |  1 -
>  arch/xtensa/Kconfig     |  1 -
>  kernel/dma/mapping.c    |  4 ----
>  sound/core/pcm_native.c | 10 +---------
>  9 files changed, 1 insertion(+), 22 deletions(-)
> 
> diff --git a/arch/Kconfig b/arch/Kconfig
> index a7b57dd42c26..ec2834206d08 100644
> --- 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 b4fb61c83494..e65e8d82442a 100644
> --- 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 c518d695c376..614b355ae338 100644
> --- a/arch/m68k/Kconfig
> +++ b/arch/m68k/Kconfig
> @@ -8,7 +8,6 @@ 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 d411de05b628..632c9477a0f6 100644
> --- 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/parisc/Kconfig b/arch/parisc/Kconfig
> index 6d732e451071..e9dd88b7f81e 100644
> --- a/arch/parisc/Kconfig
> +++ b/arch/parisc/Kconfig
> @@ -52,7 +52,6 @@ config PARISC
>  	select GENERIC_SCHED_CLOCK
>  	select HAVE_UNSTABLE_SCHED_CLOCK if SMP
>  	select GENERIC_CLOCKEVENTS
> -	select ARCH_NO_COHERENT_DMA_MMAP
>  	select CPU_NO_EFFICIENT_FFS
>  	select NEED_DMA_MAP_STATE
>  	select NEED_SG_DMA_LENGTH
> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> index 6b1b5941b618..f356ee674d89 100644
> --- 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 ebc135bda921..70653aed3005 100644
> --- 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 7dff1829c8c5..815446f76995 100644
> --- a/kernel/dma/mapping.c
> +++ b/kernel/dma/mapping.c
> @@ -169,7 +169,6 @@ 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
>  	unsigned long user_count = vma_pages(vma);
>  	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
>  	unsigned long off = vma->vm_pgoff;
> @@ -198,9 +197,6 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
>  
>  	return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
>  			user_count << PAGE_SHIFT, vma->vm_page_prot);
> -#else
> -	return -ENXIO;
> -#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
>  }
>  
>  /**
> diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
> index 860543a4c840..2dadc708343a 100644
> --- a/sound/core/pcm_native.c
> +++ b/sound/core/pcm_native.c
> @@ -218,15 +218,7 @@ int snd_pcm_info_user(struct snd_pcm_substream *substream,
>  
>  static bool hw_support_mmap(struct snd_pcm_substream *substream)
>  {
> -	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
> -		return false;
> -	/* architecture supports dma_mmap_coherent()? */
> -#if defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) || !defined(CONFIG_HAS_DMA)
> -	if (!substream->ops->mmap &&
> -	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
> -		return false;
> -#endif
> -	return true;
> +	return substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP;
>  }
>  
>  static int constrain_mask_params(struct snd_pcm_substream *substream,
> -- 
> 2.20.1
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
---end quoted text---
Takashi Iwai Aug. 2, 2019, 8:24 a.m. UTC | #2
On Fri, 02 Aug 2019 09:03:54 +0200,
Christoph Hellwig wrote:
> 
> Takashi,
> 
> any comments on the sounds/ side of this?

I wasn't careful enough to look at that change, sorry.

The code there tries to check whether dma_mmap_coherent() would always
fail on some platforms.  Then the driver clears the mmap capability
flag at the device open time and notifies user-space to fall back to
the dumb read/write mode.

So I'm afraid that simply dropping the check would cause the behavior
regression, e.g. on PARISC.

Is there any simple way to test whether dma_mmap_coherent() would work
or not in general on the target platform?  It's not necessarily in an
ifdef at all.


thanks,

Takashi

> On Thu, Jul 25, 2019 at 08:34:01AM +0200, Christoph Hellwig wrote:
> > Now that we never use a default ->mmap implementation, and non-coherent
> > architectures can control the presence of ->mmap support by enabling
> > ARCH_HAS_DMA_COHERENT_TO_PFN for the dma direct implementation there
> > is no need for a global config option to control the availability
> > of dma_common_mmap.
> > 
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> > ---
> >  arch/Kconfig            |  3 ---
> >  arch/c6x/Kconfig        |  1 -
> >  arch/m68k/Kconfig       |  1 -
> >  arch/microblaze/Kconfig |  1 -
> >  arch/parisc/Kconfig     |  1 -
> >  arch/sh/Kconfig         |  1 -
> >  arch/xtensa/Kconfig     |  1 -
> >  kernel/dma/mapping.c    |  4 ----
> >  sound/core/pcm_native.c | 10 +---------
> >  9 files changed, 1 insertion(+), 22 deletions(-)
> > 
> > diff --git a/arch/Kconfig b/arch/Kconfig
> > index a7b57dd42c26..ec2834206d08 100644
> > --- 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 b4fb61c83494..e65e8d82442a 100644
> > --- 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 c518d695c376..614b355ae338 100644
> > --- a/arch/m68k/Kconfig
> > +++ b/arch/m68k/Kconfig
> > @@ -8,7 +8,6 @@ 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 d411de05b628..632c9477a0f6 100644
> > --- 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/parisc/Kconfig b/arch/parisc/Kconfig
> > index 6d732e451071..e9dd88b7f81e 100644
> > --- a/arch/parisc/Kconfig
> > +++ b/arch/parisc/Kconfig
> > @@ -52,7 +52,6 @@ config PARISC
> >  	select GENERIC_SCHED_CLOCK
> >  	select HAVE_UNSTABLE_SCHED_CLOCK if SMP
> >  	select GENERIC_CLOCKEVENTS
> > -	select ARCH_NO_COHERENT_DMA_MMAP
> >  	select CPU_NO_EFFICIENT_FFS
> >  	select NEED_DMA_MAP_STATE
> >  	select NEED_SG_DMA_LENGTH
> > diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> > index 6b1b5941b618..f356ee674d89 100644
> > --- 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 ebc135bda921..70653aed3005 100644
> > --- 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 7dff1829c8c5..815446f76995 100644
> > --- a/kernel/dma/mapping.c
> > +++ b/kernel/dma/mapping.c
> > @@ -169,7 +169,6 @@ 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
> >  	unsigned long user_count = vma_pages(vma);
> >  	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
> >  	unsigned long off = vma->vm_pgoff;
> > @@ -198,9 +197,6 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
> >  
> >  	return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
> >  			user_count << PAGE_SHIFT, vma->vm_page_prot);
> > -#else
> > -	return -ENXIO;
> > -#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
> >  }
> >  
> >  /**
> > diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
> > index 860543a4c840..2dadc708343a 100644
> > --- a/sound/core/pcm_native.c
> > +++ b/sound/core/pcm_native.c
> > @@ -218,15 +218,7 @@ int snd_pcm_info_user(struct snd_pcm_substream *substream,
> >  
> >  static bool hw_support_mmap(struct snd_pcm_substream *substream)
> >  {
> > -	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
> > -		return false;
> > -	/* architecture supports dma_mmap_coherent()? */
> > -#if defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) || !defined(CONFIG_HAS_DMA)
> > -	if (!substream->ops->mmap &&
> > -	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
> > -		return false;
> > -#endif
> > -	return true;
> > +	return substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP;
> >  }
> >  
> >  static int constrain_mask_params(struct snd_pcm_substream *substream,
> > -- 
> > 2.20.1
> > 
> > 
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> ---end quoted text---
>
Christoph Hellwig Aug. 3, 2019, 10:30 a.m. UTC | #3
On Fri, Aug 02, 2019 at 10:24:02AM +0200, Takashi Iwai wrote:
> I wasn't careful enough to look at that change, sorry.
> 
> The code there tries to check whether dma_mmap_coherent() would always
> fail on some platforms.  Then the driver clears the mmap capability
> flag at the device open time and notifies user-space to fall back to
> the dumb read/write mode.
> 
> So I'm afraid that simply dropping the check would cause the behavior
> regression, e.g. on PARISC.
> 
> Is there any simple way to test whether dma_mmap_coherent() would work
> or not in general on the target platform?  It's not necessarily in an
> ifdef at all.

This isn't really a platform, but a per-device question.  I can add a
"bool dma_can_mmap(struct device *dev)" helper to check that.  But how
do I get at a suitable struct device in hw_support_mmap()?
Takashi Iwai Aug. 3, 2019, 11:22 a.m. UTC | #4
On Sat, 03 Aug 2019 12:30:24 +0200,
Christoph Hellwig wrote:
> 
> On Fri, Aug 02, 2019 at 10:24:02AM +0200, Takashi Iwai wrote:
> > I wasn't careful enough to look at that change, sorry.
> > 
> > The code there tries to check whether dma_mmap_coherent() would always
> > fail on some platforms.  Then the driver clears the mmap capability
> > flag at the device open time and notifies user-space to fall back to
> > the dumb read/write mode.
> > 
> > So I'm afraid that simply dropping the check would cause the behavior
> > regression, e.g. on PARISC.
> > 
> > Is there any simple way to test whether dma_mmap_coherent() would work
> > or not in general on the target platform?  It's not necessarily in an
> > ifdef at all.
> 
> This isn't really a platform, but a per-device question.  I can add a
> "bool dma_can_mmap(struct device *dev)" helper to check that.

Yes, this would fit perfect.

> But how
> do I get at a suitable struct device in hw_support_mmap()?

substream->dma_buffer.dev.dev can be that, which is used in the mmap
helper side, snd_pcm_lib_default_mmap().


Thanks!

Takashi

Patch
diff mbox series

diff --git a/arch/Kconfig b/arch/Kconfig
index a7b57dd42c26..ec2834206d08 100644
--- 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 b4fb61c83494..e65e8d82442a 100644
--- 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 c518d695c376..614b355ae338 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -8,7 +8,6 @@  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 d411de05b628..632c9477a0f6 100644
--- 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/parisc/Kconfig b/arch/parisc/Kconfig
index 6d732e451071..e9dd88b7f81e 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -52,7 +52,6 @@  config PARISC
 	select GENERIC_SCHED_CLOCK
 	select HAVE_UNSTABLE_SCHED_CLOCK if SMP
 	select GENERIC_CLOCKEVENTS
-	select ARCH_NO_COHERENT_DMA_MMAP
 	select CPU_NO_EFFICIENT_FFS
 	select NEED_DMA_MAP_STATE
 	select NEED_SG_DMA_LENGTH
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 6b1b5941b618..f356ee674d89 100644
--- 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 ebc135bda921..70653aed3005 100644
--- 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 7dff1829c8c5..815446f76995 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -169,7 +169,6 @@  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
 	unsigned long user_count = vma_pages(vma);
 	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 	unsigned long off = vma->vm_pgoff;
@@ -198,9 +197,6 @@  int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
 
 	return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
 			user_count << PAGE_SHIFT, vma->vm_page_prot);
-#else
-	return -ENXIO;
-#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
 }
 
 /**
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 860543a4c840..2dadc708343a 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -218,15 +218,7 @@  int snd_pcm_info_user(struct snd_pcm_substream *substream,
 
 static bool hw_support_mmap(struct snd_pcm_substream *substream)
 {
-	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
-		return false;
-	/* architecture supports dma_mmap_coherent()? */
-#if defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) || !defined(CONFIG_HAS_DMA)
-	if (!substream->ops->mmap &&
-	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
-		return false;
-#endif
-	return true;
+	return substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP;
 }
 
 static int constrain_mask_params(struct snd_pcm_substream *substream,