Re: [RFC PATCH 2/7] mm: move vma_modify() and helpers to internal header

From: Liam R. Howlett
Date: Thu Jun 27 2024 - 13:26:39 EST


* Lorenzo Stoakes <lstoakes@xxxxxxxxx> [240627 06:39]:
> These are core VMA manipulation functions which ultimately invoke VMA
> splitting and merging and should not be directly accessed from outside of
> mm/ functionality.
>
> We ultimately intend to ultimately move these to a VMA-specific internal
> header.

Too (two?) ultimate of a statement.

>
> Signed-off-by: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
> ---
> include/linux/mm.h | 60 ---------------------------------------------
> mm/internal.h | 61 ++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 61 insertions(+), 60 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 5f1075d19600..4d2b5538925b 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -3285,66 +3285,6 @@ extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
> unsigned long addr, unsigned long len, pgoff_t pgoff,
> bool *need_rmap_locks);
> extern void exit_mmap(struct mm_struct *);
> -struct vm_area_struct *vma_modify(struct vma_iterator *vmi,
> - struct vm_area_struct *prev,
> - struct vm_area_struct *vma,
> - unsigned long start, unsigned long end,
> - unsigned long vm_flags,
> - struct mempolicy *policy,
> - struct vm_userfaultfd_ctx uffd_ctx,
> - struct anon_vma_name *anon_name);
> -
> -/* We are about to modify the VMA's flags. */
> -static inline struct vm_area_struct
> -*vma_modify_flags(struct vma_iterator *vmi,
> - struct vm_area_struct *prev,
> - struct vm_area_struct *vma,
> - unsigned long start, unsigned long end,
> - unsigned long new_flags)
> -{
> - return vma_modify(vmi, prev, vma, start, end, new_flags,
> - vma_policy(vma), vma->vm_userfaultfd_ctx,
> - anon_vma_name(vma));
> -}
> -
> -/* We are about to modify the VMA's flags and/or anon_name. */
> -static inline struct vm_area_struct
> -*vma_modify_flags_name(struct vma_iterator *vmi,
> - struct vm_area_struct *prev,
> - struct vm_area_struct *vma,
> - unsigned long start,
> - unsigned long end,
> - unsigned long new_flags,
> - struct anon_vma_name *new_name)
> -{
> - return vma_modify(vmi, prev, vma, start, end, new_flags,
> - vma_policy(vma), vma->vm_userfaultfd_ctx, new_name);
> -}
> -
> -/* We are about to modify the VMA's memory policy. */
> -static inline struct vm_area_struct
> -*vma_modify_policy(struct vma_iterator *vmi,
> - struct vm_area_struct *prev,
> - struct vm_area_struct *vma,
> - unsigned long start, unsigned long end,
> - struct mempolicy *new_pol)
> -{
> - return vma_modify(vmi, prev, vma, start, end, vma->vm_flags,
> - new_pol, vma->vm_userfaultfd_ctx, anon_vma_name(vma));
> -}
> -
> -/* We are about to modify the VMA's flags and/or uffd context. */
> -static inline struct vm_area_struct
> -*vma_modify_flags_uffd(struct vma_iterator *vmi,
> - struct vm_area_struct *prev,
> - struct vm_area_struct *vma,
> - unsigned long start, unsigned long end,
> - unsigned long new_flags,
> - struct vm_userfaultfd_ctx new_ctx)
> -{
> - return vma_modify(vmi, prev, vma, start, end, new_flags,
> - vma_policy(vma), new_ctx, anon_vma_name(vma));
> -}
>
> static inline int check_data_rlimit(unsigned long rlim,
> unsigned long new,
> diff --git a/mm/internal.h b/mm/internal.h
> index 2ea9a88dcb95..c8177200c943 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -1244,6 +1244,67 @@ struct vm_area_struct *vma_merge_extend(struct vma_iterator *vmi,
> struct vm_area_struct *vma,
> unsigned long delta);
>
> +struct vm_area_struct *vma_modify(struct vma_iterator *vmi,
> + struct vm_area_struct *prev,
> + struct vm_area_struct *vma,
> + unsigned long start, unsigned long end,
> + unsigned long vm_flags,
> + struct mempolicy *policy,
> + struct vm_userfaultfd_ctx uffd_ctx,
> + struct anon_vma_name *anon_name);
> +
> +/* We are about to modify the VMA's flags. */
> +static inline struct vm_area_struct
> +*vma_modify_flags(struct vma_iterator *vmi,
> + struct vm_area_struct *prev,
> + struct vm_area_struct *vma,
> + unsigned long start, unsigned long end,
> + unsigned long new_flags)
> +{
> + return vma_modify(vmi, prev, vma, start, end, new_flags,
> + vma_policy(vma), vma->vm_userfaultfd_ctx,
> + anon_vma_name(vma));
> +}
> +
> +/* We are about to modify the VMA's flags and/or anon_name. */
> +static inline struct vm_area_struct
> +*vma_modify_flags_name(struct vma_iterator *vmi,
> + struct vm_area_struct *prev,
> + struct vm_area_struct *vma,
> + unsigned long start,
> + unsigned long end,
> + unsigned long new_flags,
> + struct anon_vma_name *new_name)
> +{
> + return vma_modify(vmi, prev, vma, start, end, new_flags,
> + vma_policy(vma), vma->vm_userfaultfd_ctx, new_name);
> +}
> +
> +/* We are about to modify the VMA's memory policy. */
> +static inline struct vm_area_struct
> +*vma_modify_policy(struct vma_iterator *vmi,
> + struct vm_area_struct *prev,
> + struct vm_area_struct *vma,
> + unsigned long start, unsigned long end,
> + struct mempolicy *new_pol)
> +{
> + return vma_modify(vmi, prev, vma, start, end, vma->vm_flags,
> + new_pol, vma->vm_userfaultfd_ctx, anon_vma_name(vma));
> +}
> +
> +/* We are about to modify the VMA's flags and/or uffd context. */
> +static inline struct vm_area_struct
> +*vma_modify_flags_uffd(struct vma_iterator *vmi,
> + struct vm_area_struct *prev,
> + struct vm_area_struct *vma,
> + unsigned long start, unsigned long end,
> + unsigned long new_flags,
> + struct vm_userfaultfd_ctx new_ctx)
> +{
> + return vma_modify(vmi, prev, vma, start, end, new_flags,
> + vma_policy(vma), new_ctx, anon_vma_name(vma));
> +}
> +
> enum {
> /* mark page accessed */
> FOLL_TOUCH = 1 << 16,
> --
> 2.45.1
>