[PATCH] powerpc: Build fix for non SPARSEMEM_VMEMAP config

We can use pfn_to_page in realmode for other configs. Hence remove the
CONFIG_FLATMEM ifdef

Fixes: 8e0861fa3c4ed (powerpc: Prepare to support kernel handling of IOMMU map/unmap)

Cc: Alexey Kardashevskiy <redacted>
Signed-off-by: Aneesh Kumar K.V <redacted>
---
 arch/powerpc/mm/init_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index ec84b31c6c86..3dd507b4f8cd 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c

@@ -322,7 +322,7 @@ struct page *realmode_pfn_to_page(unsigned long pfn)
 }
 EXPORT_SYMBOL_GPL(realmode_pfn_to_page);
 
-#elif defined(CONFIG_FLATMEM)
+#else
 
 struct page *realmode_pfn_to_page(unsigned long pfn)
 {

-- 
2.7.4

On 28/06/17 16:09, Aneesh Kumar K.V wrote:

We can use pfn_to_page in realmode for other configs. Hence remove the
CONFIG_FLATMEM ifdef

For CONFIG_SPARSEMEM and CONFIG_DISCONTIGMEM and others (I am struggling to
find the full list :) )? Are you sure about that? If I recall correctly, at
the time realmode_pfn_to_page() could not work for all of them, what changed?

There is also a comment at the #endif with "FLATMEM", needs to be updated.

 
 struct page *realmode_pfn_to_page(unsigned long pfn)
 {

-- 
Alexey

On Wednesday 28 June 2017 12:48 PM, Alexey Kardashevskiy wrote:

On 28/06/17 16:09, Aneesh Kumar K.V wrote:

quoted

We can use pfn_to_page in realmode for other configs. Hence remove the
CONFIG_FLATMEM ifdef

For CONFIG_SPARSEMEM and CONFIG_DISCONTIGMEM and others (I am struggling to
find the full list :) )? Are you sure about that? If I recall correctly, at
the time realmode_pfn_to_page() could not work for all of them, what changed?

That is one thing I wanted to check. Everything other than 
SPARSEMEM_VMEMMAP should use linear mapping which can work with real 
mode also right ? Or am i missing something ?

quoted

Fixes: 8e0861fa3c4ed (powerpc: Prepare to support kernel handling of IOMMU map/unmap)

Cc: Alexey Kardashevskiy <redacted>
Signed-off-by: Aneesh Kumar K.V <redacted>
---
  arch/powerpc/mm/init_64.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index ec84b31c6c86..3dd507b4f8cd 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c

@@ -322,7 +322,7 @@ struct page *realmode_pfn_to_page(unsigned long pfn)
  }
  EXPORT_SYMBOL_GPL(realmode_pfn_to_page);
  
-#elif defined(CONFIG_FLATMEM)
+#else

There is also a comment at the #endif with "FLATMEM", needs to be updated.

quoted

  
  struct page *realmode_pfn_to_page(unsigned long pfn)
  {

"Aneesh Kumar K.V" [off-list ref] writes:

On Wednesday 28 June 2017 12:48 PM, Alexey Kardashevskiy wrote:

quoted

On 28/06/17 16:09, Aneesh Kumar K.V wrote:

quoted

We can use pfn_to_page in realmode for other configs. Hence remove the
CONFIG_FLATMEM ifdef

For CONFIG_SPARSEMEM and CONFIG_DISCONTIGMEM and others (I am struggling to
find the full list :) )? Are you sure about that? If I recall correctly, at
the time realmode_pfn_to_page() could not work for all of them, what changed?

That is one thing I wanted to check. Everything other than 
SPARSEMEM_VMEMMAP should use linear mapping which can work with real 
mode also right ? Or am i missing something ?

I think that's right. But I'm going to make you test it anyway :)

cheers

Michael Ellerman [off-list ref] writes:

"Aneesh Kumar K.V" [off-list ref] writes:

quoted

On Wednesday 28 June 2017 12:48 PM, Alexey Kardashevskiy wrote:

quoted

On 28/06/17 16:09, Aneesh Kumar K.V wrote:

quoted

We can use pfn_to_page in realmode for other configs. Hence remove the
CONFIG_FLATMEM ifdef

For CONFIG_SPARSEMEM and CONFIG_DISCONTIGMEM and others (I am struggling to
find the full list :) )? Are you sure about that? If I recall correctly, at
the time realmode_pfn_to_page() could not work for all of them, what changed?

That is one thing I wanted to check. Everything other than 
SPARSEMEM_VMEMMAP should use linear mapping which can work with real 
mode also right ? Or am i missing something ?

I think that's right. But I'm going to make you test it anyway :)

Tested this by printing page->flags with FLATMEM, SPARSEMEM and
SPARSEMEM_VMEMMAP in kvm real mode handler.

-aneesh

On Wed, 2017-06-28 at 06:09:28 UTC, "Aneesh Kumar K.V" wrote:

We can use pfn_to_page in realmode for other configs. Hence remove the
CONFIG_FLATMEM ifdef

Fixes: 8e0861fa3c4ed (powerpc: Prepare to support kernel handling of IOMMU map/unmap)

Cc: Alexey Kardashevskiy <redacted>
Signed-off-by: Aneesh Kumar K.V <redacted>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/7e7dc66adcf490a619bc3c7763a8ce

cheers