Commit f2ebfe43 authored by Liam R. Howlett's avatar Liam R. Howlett Committed by Andrew Morton
Browse files

mm: add temporary vma iterator versions of vma_merge(), split_vma(), and __split_vma() 

These wrappers are short-lived in this patch set so that each user can be
converted on its own.  In the end, these functions are renamed in one
commit.

Link: https://lkml.kernel.org/r/20230120162650.984577-15-Liam.Howlett@oracle.com


Signed-off-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 3c441ab7

include/linux/mm.h

+10 −1
Original line number Diff line number Diff line
@@ -2843,11 +2843,20 @@ extern struct vm_area_struct *vma_merge(struct mm_struct *, 
	struct vm_area_struct *prev, unsigned long addr, unsigned long end,

	unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t,

	struct mempolicy *, struct vm_userfaultfd_ctx, struct anon_vma_name *);

extern struct vm_area_struct *vmi_vma_merge(struct vma_iterator *vmi,

	struct mm_struct *, struct vm_area_struct *prev, unsigned long addr,

	unsigned long end, unsigned long vm_flags, struct anon_vma *,

	struct file *, pgoff_t, struct mempolicy *, struct vm_userfaultfd_ctx,

	struct anon_vma_name *);

extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);

extern int __split_vma(struct mm_struct *, struct vm_area_struct *,

			       unsigned long addr, int new_below);

extern int vmi__split_vma(struct vma_iterator *vmi, struct mm_struct *,

	struct vm_area_struct *, unsigned long addr, int new_below);

extern int split_vma(struct mm_struct *, struct vm_area_struct *,

	unsigned long addr, int new_below);

extern int vmi_split_vma(struct vma_iterator *vmi, struct mm_struct *,

		struct vm_area_struct *, unsigned long addr, int new_below);

extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);

extern void unlink_file_vma(struct vm_area_struct *);

extern struct vm_area_struct *copy_vma(struct vm_area_struct **,

mm/mmap.c

+44 −0
Original line number Diff line number Diff line
@@ -1091,6 +1091,25 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm, 
	return res;

}



struct vm_area_struct *vmi_vma_merge(struct vma_iterator *vmi,

			struct mm_struct *mm,

			struct vm_area_struct *prev, unsigned long addr,

			unsigned long end, unsigned long vm_flags,

			struct anon_vma *anon_vma, struct file *file,

			pgoff_t pgoff, struct mempolicy *policy,

			struct vm_userfaultfd_ctx vm_userfaultfd_ctx,

			struct anon_vma_name *anon_name)

{

	struct vm_area_struct *tmp;



	tmp = vma_merge(mm, prev, addr, end, vm_flags, anon_vma, file, pgoff,

			policy, vm_userfaultfd_ctx, anon_name);

	if (tmp)

		vma_iter_set(vmi, end);



	return tmp;

}



/*

 * Rough compatibility check to quickly see if it's even worth looking

 * at sharing an anon_vma.
@@ -2276,6 +2295,18 @@ int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma, 
	validate_mm_mt(mm);

	return err;

}

int vmi__split_vma(struct vma_iterator *vmi, struct mm_struct *mm,

		   struct vm_area_struct *vma, unsigned long addr, int new_below)

{

	int ret;

	unsigned long end = vma->vm_end;



	ret = __split_vma(mm, vma, addr, new_below);

	if (!ret)

		vma_iter_set(vmi, end);



	return ret;

}



/*

 * Split a vma into two pieces at address 'addr', a new vma is allocated
@@ -2290,6 +2321,19 @@ int split_vma(struct mm_struct *mm, struct vm_area_struct *vma, 
	return __split_vma(mm, vma, addr, new_below);

}



int vmi_split_vma(struct vma_iterator *vmi, struct mm_struct *mm,

		  struct vm_area_struct *vma, unsigned long addr, int new_below)

{

	int ret;

	unsigned long end = vma->vm_end;



	ret = split_vma(mm, vma, addr, new_below);

	if (!ret)

		vma_iter_set(vmi, end);



	return ret;

}



static inline int munmap_sidetree(struct vm_area_struct *vma,

				   struct ma_state *mas_detach)

{