On Tue, Sep 03, 2024 at 04:22:40PM -0700, Anthony Yznaga wrote:
> In preparation for mapping objects into an mshare region, create
> __do_mmap() to allow mapping into a specified mm. There are no
> functional changes otherwise.
>
> Signed-off-by: Anthony Yznaga <anthony.yznaga@xxxxxxxxxx>
> ---
> include/linux/mm.h | 18 +++++++++++++++++-
> mm/mmap.c | 12 +++++-------
> 2 files changed, 22 insertions(+), 8 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 3aa0b3322284..a9afbda73cb0 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -3409,11 +3409,27 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
>
> extern unsigned long mmap_region(struct file *file, unsigned long addr,
> unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
> - struct list_head *uf);
> + struct list_head *uf, struct mm_struct *mm);
> +#ifdef CONFIG_MMU
> +extern unsigned long __do_mmap(struct file *file, unsigned long addr,
> + unsigned long len, unsigned long prot, unsigned long flags,
> + vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate,
> + struct list_head *uf, struct mm_struct *mm);
> +static inline unsigned long do_mmap(struct file *file, unsigned long addr,
> + unsigned long len, unsigned long prot, unsigned long flags,
> + vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate,
> + struct list_head *uf)
> +{
> + return __do_mmap(file, addr, len, prot, flags, vm_flags, pgoff,
> + populate, uf, current->mm);
> +}
> +#else
> extern unsigned long do_mmap(struct file *file, unsigned long addr,
> unsigned long len, unsigned long prot, unsigned long flags,
> vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate,
> struct list_head *uf);
> +#endif
> +
> extern int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm,
> unsigned long start, size_t len, struct list_head *uf,
> bool unlock);
> diff --git a/mm/mmap.c b/mm/mmap.c
> index d0dfc85b209b..4112f18e7302 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1250,15 +1250,14 @@ static inline bool file_mmap_ok(struct file *file, struct inode *inode,
> }
>
> /*
> - * The caller must write-lock current->mm->mmap_lock.
> + * The caller must write-lock mm->mmap_lock.
> */
> -unsigned long do_mmap(struct file *file, unsigned long addr,
> +unsigned long __do_mmap(struct file *file, unsigned long addr,
> unsigned long len, unsigned long prot,
> unsigned long flags, vm_flags_t vm_flags,
> unsigned long pgoff, unsigned long *populate,
> - struct list_head *uf)
> + struct list_head *uf, struct mm_struct *mm)
Argument list getting too long. At some point we need to have a struct to
pass them around.
> {
> - struct mm_struct *mm = current->mm;
> int pkey = 0;
>
> *populate = 0;
> @@ -1465,7 +1464,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
> vm_flags |= VM_NORESERVE;
> }
>
> - addr = mmap_region(file, addr, len, vm_flags, pgoff, uf);
> + addr = mmap_region(file, addr, len, vm_flags, pgoff, uf, mm);
> if (!IS_ERR_VALUE(addr) &&
> ((vm_flags & VM_LOCKED) ||
> (flags & (MAP_POPULATE | MAP_NONBLOCK)) == MAP_POPULATE))
> @@ -2848,9 +2847,8 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
>
> unsigned long mmap_region(struct file *file, unsigned long addr,
> unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
> - struct list_head *uf)
> + struct list_head *uf, struct mm_struct *mm)
> {
> - struct mm_struct *mm = current->mm;
> struct vm_area_struct *vma = NULL;
> struct vm_area_struct *next, *prev, *merge;
> pgoff_t pglen = len >> PAGE_SHIFT;
> --
> 2.43.5
>
--
Kiryl Shutsemau / Kirill A. Shutemov
