Re: [PATCH] mm/hmm: fix header file if/else/endif maze, again

[Jerome Glisse <jglisse@redhat.com>]

On Wed, Apr 04, 2018 at 01:02:15PM +0200, Arnd Bergmann wrote:
> The last fix was still wrong, as we need the inline dummy functions
> also for the case that CONFIG_HMM is enabled but CONFIG_HMM_MIRROR
> is not:
> 
> kernel/fork.o: In function `__mmdrop':
> fork.c:(.text+0x14f6): undefined reference to `hmm_mm_destroy'
> 
> This adds back the second copy of the dummy functions, hopefully
> this time in the right place.
> 
> Fixes: 8900d06a277a ("mm/hmm: fix header file if/else/endif maze")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Reviewed-by: Jerome Glisse <jglisse@redhat.com>

Hopefuly this is the last config combinatorial issue...

> ---
>  include/linux/hmm.h | 21 ++++++++++++---------
>  1 file changed, 12 insertions(+), 9 deletions(-)
> 
> diff --git a/include/linux/hmm.h b/include/linux/hmm.h
> index 5d26e0a223d9..39988924de3a 100644
> --- a/include/linux/hmm.h
> +++ b/include/linux/hmm.h
> @@ -376,8 +376,18 @@ bool hmm_vma_range_done(struct hmm_range *range);
>   * See the function description in mm/hmm.c for further documentation.
>   */
>  int hmm_vma_fault(struct hmm_range *range, bool block);
> -#endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */
>  
> +/* Below are for HMM internal use only! Not to be used by device driver! */
> +void hmm_mm_destroy(struct mm_struct *mm);
> +
> +static inline void hmm_mm_init(struct mm_struct *mm)
> +{
> +	mm->hmm = NULL;
> +}
> +#else /* IS_ENABLED(CONFIG_HMM_MIRROR) */
> +static inline void hmm_mm_destroy(struct mm_struct *mm) {}
> +static inline void hmm_mm_init(struct mm_struct *mm) {}
> +#endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */
>  
>  #if IS_ENABLED(CONFIG_DEVICE_PRIVATE) ||  IS_ENABLED(CONFIG_DEVICE_PUBLIC)
>  struct hmm_devmem;
> @@ -550,16 +560,9 @@ struct hmm_device {
>  struct hmm_device *hmm_device_new(void *drvdata);
>  void hmm_device_put(struct hmm_device *hmm_device);
>  #endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
> -
> -/* Below are for HMM internal use only! Not to be used by device driver! */
> -void hmm_mm_destroy(struct mm_struct *mm);
> -
> -static inline void hmm_mm_init(struct mm_struct *mm)
> -{
> -	mm->hmm = NULL;
> -}
>  #else /* IS_ENABLED(CONFIG_HMM) */
>  static inline void hmm_mm_destroy(struct mm_struct *mm) {}
>  static inline void hmm_mm_init(struct mm_struct *mm) {}
>  #endif /* IS_ENABLED(CONFIG_HMM) */
> +
>  #endif /* LINUX_HMM_H */
> -- 
> 2.9.0
>