Re: [PATCH 2/9] arch/arm/mm/dma-mapping.c: Convert to use vm_insert_range

[Souptick Joarder]

On Fri, Jan 25, 2019 at 11:54 AM Souptick Joarder <jrdr.linux@xxxxxxxxx> wrote:
>
> On Fri, Jan 11, 2019 at 8:33 PM Souptick Joarder <jrdr.linux@xxxxxxxxx> wrote:
> >
> > Convert to use vm_insert_range() to map range of kernel
> > memory to user vma.
> >
> > Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx>
>
> Any comment on this patch ?

Any comment on this patch ?

>
> > ---
> >  arch/arm/mm/dma-mapping.c | 22 ++++++----------------
> >  1 file changed, 6 insertions(+), 16 deletions(-)
> >
> > diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
> > index 78de138..5334391 100644
> > --- a/arch/arm/mm/dma-mapping.c
> > +++ b/arch/arm/mm/dma-mapping.c
> > @@ -1582,31 +1582,21 @@ static int __arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma
> >                     void *cpu_addr, dma_addr_t dma_addr, size_t size,
> >                     unsigned long attrs)
> >  {
> > -       unsigned long uaddr = vma->vm_start;
> > -       unsigned long usize = vma->vm_end - vma->vm_start;
> >         struct page **pages = __iommu_get_pages(cpu_addr, attrs);
> >         unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
> > -       unsigned long off = vma->vm_pgoff;
> > +       int err;
> >
> >         if (!pages)
> >                 return -ENXIO;
> >
> > -       if (off >= nr_pages || (usize >> PAGE_SHIFT) > nr_pages - off)
> > +       if (vma->vm_pgoff >= nr_pages)
> >                 return -ENXIO;
> >
> > -       pages += off;
> > -
> > -       do {
> > -               int ret = vm_insert_page(vma, uaddr, *pages++);
> > -               if (ret) {
> > -                       pr_err("Remapping memory failed: %d\n", ret);
> > -                       return ret;
> > -               }
> > -               uaddr += PAGE_SIZE;
> > -               usize -= PAGE_SIZE;
> > -       } while (usize > 0);
> > +       err = vm_insert_range(vma, pages, nr_pages);
> > +       if (err)
> > +               pr_err("Remapping memory failed: %d\n", err);
> >
> > -       return 0;
> > +       return err;
> >  }
> >  static int arm_iommu_mmap_attrs(struct device *dev,
> >                 struct vm_area_struct *vma, void *cpu_addr,
> > --
> > 1.9.1
> >