[RESEND 5/7] IB/hfi1: Use the new FOLL_LONGTERM flag to get_user_pages_fast()

[Dan Williams]

On Sun, Mar 17, 2019 at 7:36 PM <ira.weiny at intel.com> wrote:
>
> From: Ira Weiny <ira.weiny at intel.com>
>
> Use the new FOLL_LONGTERM to get_user_pages_fast() to protect against
> FS DAX pages being mapped.
>
> Signed-off-by: Ira Weiny <ira.weiny at intel.com>
> ---
>  drivers/infiniband/hw/hfi1/user_pages.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/infiniband/hw/hfi1/user_pages.c b/drivers/infiniband/hw/hfi1/user_pages.c
> index 78ccacaf97d0..6a7f9cd5a94e 100644
> --- a/drivers/infiniband/hw/hfi1/user_pages.c
> +++ b/drivers/infiniband/hw/hfi1/user_pages.c
> @@ -104,9 +104,11 @@ int hfi1_acquire_user_pages(struct mm_struct *mm, unsigned long vaddr, size_t np
>                             bool writable, struct page **pages)
>  {
>         int ret;
> +       unsigned int gup_flags = writable ? FOLL_WRITE : 0;

Maybe:

    unsigned int gup_flags = FOLL_LONGTERM | (writable ? FOLL_WRITE : 0);

?

>
> -       ret = get_user_pages_fast(vaddr, npages, writable ? FOLL_WRITE : 0,
> -                                 pages);
> +       gup_flags |= FOLL_LONGTERM;
> +
> +       ret = get_user_pages_fast(vaddr, npages, gup_flags, pages);
>         if (ret < 0)
>                 return ret;
>
> --
> 2.20.1
>