Re: [PATCH] mm, hugetlbfs: include mm.h for vm_operations_struct

[Stephen Rothwell]

Hi Michal,

On Tue, 12 Dec 2017 08:47:22 +0100 Michal Hocko <mhocko@xxxxxxxxxx> wrote:
>
> On Mon 11-12-17 17:21:27, Arnd Bergmann wrote:
> > The infiniband umem code causes a build failure in some configurations:
> > 
> > In file included from drivers/infiniband/core/umem_odp.c:41:0:
> > include/linux/hugetlb.h: In function 'vma_kernel_pagesize':
> > include/linux/hugetlb.h:262:32: error: dereferencing pointer to incomplete type 'const struct vm_operations_struct'
> > 
> > Including the header file that defines the structure is sufficient to
> > avoid this.
> > 
> > Fixes: ac9284a6b670 ("mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct")
> > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>  
> 
> I've tried to do the same but the compilation failed for other
> arches/configs. See http://lkml.kernel.org/r/20171210113715.GE20234@xxxxxxxxxxxxxx

I sent a patch yesterday for that particular powerpc failure ... You
were not CC'd, but I have attached the email.
-- 
Cheers,
Stephen Rothwell
> --- Begin Message ---
> Hi Andrew,
>
> After merging the akpm-current tree, today's linux-next build (powerpc
> ppc64_defconfig) failed like this:
>
> In file included from include/linux/hugetlb.h:451:0,
>                  from arch/powerpc/mm/hugetlbpage.c:14:
> arch/powerpc/include/asm/hugetlb.h:125:26: error: redefinition of 'vma_mmu_pagesize'
>  #define vma_mmu_pagesize vma_mmu_pagesize
>                           ^
> arch/powerpc/mm/hugetlbpage.c:563:15: note: in expansion of macro 'vma_mmu_pagesize'
>  unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
>                ^
> In file included from arch/powerpc/mm/hugetlbpage.c:14:0:
> include/linux/hugetlb.h:274:29: note: previous definition of 'vma_mmu_pagesize' was here
>  static inline unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
>                              ^
>
> Caused by commit
>
>   ac9284a6b670 ("mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct")
>
> I have added the following fix patch for today:
>
> From: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> Date: Mon, 11 Dec 2017 15:51:41 +1100
> Subject: [PATCH] mm, hugetlbfs: move testing of vma_mmu_pagesize to after
>  inclusion of asm/hugetlb.h
>
> Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> ---
>  arch/powerpc/include/asm/hugetlb.h |  1 +
>  include/linux/hugetlb.h            | 26 +++++++++++++-------------
>  2 files changed, 14 insertions(+), 13 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/hugetlb.h b/arch/powerpc/include/asm/hugetlb.h
> index 14c9d44f355b..3cc6ca1bdaf2 100644
> --- a/arch/powerpc/include/asm/hugetlb.h
> +++ b/arch/powerpc/include/asm/hugetlb.h
> @@ -123,6 +123,7 @@ void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
>   * to override the version in mm/hugetlb.c
>   */
>  #define vma_mmu_pagesize vma_mmu_pagesize
> +unsigned long vma_mmu_pagesize(struct vm_area_struct *vma);
>  
>  /*
>   * If the arch doesn't supply something else, assume that hugepage
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index c354befab724..b0f1f6768336 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -264,19 +264,6 @@ static inline unsigned long vma_kernel_pagesize(struct vm_area_struct *vma)
>  	return PAGE_SIZE;
>  }
>  
> -/*
> - * Return the page size being used by the MMU to back a VMA. In the majority
> - * of cases, the page size used by the kernel matches the MMU size. On
> - * architectures where it differs, an architecture-specific version of this
> - * function is required.
> - */
> -#ifndef vma_mmu_pagesize
> -static inline unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
> -{
> -	return vma_kernel_pagesize(vma);
> -}
> -#endif
> -
>  #ifdef CONFIG_HUGETLBFS
>  struct hugetlbfs_sb_info {
>  	long	max_inodes;   /* inodes allowed */
> @@ -615,6 +602,19 @@ static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr
>  }
>  #endif	/* CONFIG_HUGETLB_PAGE */
>  
> +/*
> + * Return the page size being used by the MMU to back a VMA. In the majority
> + * of cases, the page size used by the kernel matches the MMU size. On
> + * architectures where it differs, an architecture-specific version of this
> + * function is required.
> + */
> +#ifndef vma_mmu_pagesize
> +static inline unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
> +{
> +	return vma_kernel_pagesize(vma);
> +}
> +#endif
> +
>  static inline spinlock_t *huge_pte_lock(struct hstate *h,
>  					struct mm_struct *mm, pte_t *pte)
>  {
> -- 
> 2.15.0
>
> -- 
> Cheers,
> Stephen Rothwell
>
> --- End Message ---