Re: [PATCH v3 01/12] mm/shmem: add `const` to lots of pointer parameters

[Lorenzo Stoakes <lorenzo.stoakes@oracle.com>]

On Mon, Sep 01, 2025 at 08:12:12AM +0200, Max Kellermann wrote:
> For improved const-correctness.

This is not an acceptable commit message, you need to explain what you're doing
here.

I'm thinking that review will be the same for each...

For instance, reference the fact you're starting with functions at the bottom of
the call graph, and mention which functions you're changing.

>
> Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>

This otherwise, functionally, LGTM so:

Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>

On basis of you fixing the commit message.

> ---
>  include/linux/mm.h       | 8 ++++----
>  include/linux/shmem_fs.h | 4 ++--
>  mm/shmem.c               | 6 +++---
>  3 files changed, 9 insertions(+), 9 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index cd14298bb958..18deb14cb1f5 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -979,11 +979,11 @@ static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr)
>   * The vma_is_shmem is not inline because it is used only by slow
>   * paths in userfault.
>   */
> -bool vma_is_shmem(struct vm_area_struct *vma);
> -bool vma_is_anon_shmem(struct vm_area_struct *vma);
> +bool vma_is_shmem(const struct vm_area_struct *vma);
> +bool vma_is_anon_shmem(const struct vm_area_struct *vma);
>  #else
> -static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; }
> -static inline bool vma_is_anon_shmem(struct vm_area_struct *vma) { return false; }
> +static inline bool vma_is_shmem(const struct vm_area_struct *vma) { return false; }
> +static inline bool vma_is_anon_shmem(const struct vm_area_struct *vma) { return false; }
>  #endif
>
>  int vma_is_stack_for_current(struct vm_area_struct *vma);
> diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
> index 6d0f9c599ff7..0e47465ef0fd 100644
> --- a/include/linux/shmem_fs.h
> +++ b/include/linux/shmem_fs.h
> @@ -99,9 +99,9 @@ extern unsigned long shmem_get_unmapped_area(struct file *, unsigned long addr,
>  		unsigned long len, unsigned long pgoff, unsigned long flags);
>  extern int shmem_lock(struct file *file, int lock, struct ucounts *ucounts);
>  #ifdef CONFIG_SHMEM
> -bool shmem_mapping(struct address_space *mapping);
> +bool shmem_mapping(const struct address_space *mapping);
>  #else
> -static inline bool shmem_mapping(struct address_space *mapping)
> +static inline bool shmem_mapping(const struct address_space *mapping)
>  {
>  	return false;
>  }
> diff --git a/mm/shmem.c b/mm/shmem.c
> index 640fecc42f60..d55bceaa1c80 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -275,18 +275,18 @@ static const struct vm_operations_struct shmem_vm_ops;
>  static const struct vm_operations_struct shmem_anon_vm_ops;
>  static struct file_system_type shmem_fs_type;
>
> -bool shmem_mapping(struct address_space *mapping)
> +bool shmem_mapping(const struct address_space *const mapping)
>  {
>  	return mapping->a_ops == &shmem_aops;
>  }
>  EXPORT_SYMBOL_GPL(shmem_mapping);
>
> -bool vma_is_anon_shmem(struct vm_area_struct *vma)
> +bool vma_is_anon_shmem(const struct vm_area_struct *const vma)
>  {
>  	return vma->vm_ops == &shmem_anon_vm_ops;
>  }
>
> -bool vma_is_shmem(struct vm_area_struct *vma)
> +bool vma_is_shmem(const struct vm_area_struct *const vma)
>  {
>  	return vma_is_anon_shmem(vma) || vma->vm_ops == &shmem_vm_ops;
>  }
> --
> 2.47.2
>