mm, powerpc: use vma_kernel_pagesize() in vma_mmu_pagesize()
Patch series "mm, smaps: MMUPageSize for device-dax", v3. Similar to commit 31383c68 ("mm, hugetlbfs: introduce ->split() to vm_operations_struct") here is another occasion where we want special-case hugetlbfs/hstate enabling to also apply to device-dax. This prompts the question what other hstate conversions we might do beyond ->split() and ->pagesize(), but this appears to be the last of the usages of hstate_vma() in generic/non-hugetlbfs specific code paths. This patch (of 3): The current powerpc definition of vma_mmu_pagesize() open codes looking up the page size via hstate. It is identical to the generic vma_kernel_pagesize() implementation. Now, vma_kernel_pagesize() is growing support for determining the page size of Device-DAX vmas in addition to the existing Hugetlbfs page size determination. Ideally, if the powerpc vma_mmu_pagesize() used vma_kernel_pagesize() it would automatically benefit from any new vma-type support that is added to vma_kernel_pagesize(). However, the powerpc vma_mmu_pagesize() is prevented from calling vma_kernel_pagesize() due to a circular header dependency that requires vma_mmu_pagesize() to be defined before including <linux/hugetlb.h>. Break this circular dependency by defining the default vma_mmu_pagesize() as a __weak symbol to be overridden by the powerpc version. Link: http://lkml.kernel.org/r/151996254179.27922.2213728278535578744.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Jane Chu <jane.chu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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