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

[Lorenzo Stoakes <lstoakes@gmail.com>]

On Thu, Jun 27, 2024 at 01:25:55PM -0400, Liam R. Howlett wrote:
> * Lorenzo Stoakes <lstoakes@gmail.com> [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.

Ultimately this was the ultimate example of me ultimately rewriting a
sentence to say ultimate while forgetting that I also said ultimate
ultimately later on in the same sentence, leading to a penultimate
ultimate.

You offer me an ultimatum on fixing this in order to receive positive
review, so ultimately I shall relent and do so on the next respin.

>
> >
> > Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
> > ---
> >  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
> >