Re: [PATCH v2 08/16] hpet: replace deprecated mmap hook with mmap_prepare

[Suren Baghdasaryan <surenb@google.com>]

On Mon, Mar 16, 2026 at 2:14 PM Lorenzo Stoakes (Oracle) <ljs@kernel.org> wrote:
>
> The f_op->mmap interface is deprecated, so update driver to use its
> successor, mmap_prepare.
>
> The driver previously used vm_iomap_memory(), so this change replaces it
> with its mmap_prepare equivalent, mmap_action_simple_ioremap().
>
> Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>

Reviewed-by: Suren Baghdasaryan <surenb@google.com>

> ---
>  drivers/char/hpet.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
> index 60dd09a56f50..8f128cc40147 100644
> --- a/drivers/char/hpet.c
> +++ b/drivers/char/hpet.c
> @@ -354,8 +354,9 @@ static __init int hpet_mmap_enable(char *str)
>  }
>  __setup("hpet_mmap=", hpet_mmap_enable);
>
> -static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
> +static int hpet_mmap_prepare(struct vm_area_desc *desc)
>  {
> +       struct file *file = desc->file;
>         struct hpet_dev *devp;
>         unsigned long addr;
>
> @@ -368,11 +369,12 @@ static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
>         if (addr & (PAGE_SIZE - 1))
>                 return -ENOSYS;
>
> -       vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
> -       return vm_iomap_memory(vma, addr, PAGE_SIZE);
> +       desc->page_prot = pgprot_noncached(desc->page_prot);
> +       mmap_action_simple_ioremap(desc, addr, PAGE_SIZE);
> +       return 0;
>  }
>  #else
> -static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
> +static int hpet_mmap_prepare(struct vm_area_desc *desc)
>  {
>         return -ENOSYS;
>  }
> @@ -710,7 +712,7 @@ static const struct file_operations hpet_fops = {
>         .open = hpet_open,
>         .release = hpet_release,
>         .fasync = hpet_fasync,
> -       .mmap = hpet_mmap,
> +       .mmap_prepare = hpet_mmap_prepare,
>  };
>
>  static int hpet_is_known(struct hpet_data *hdp)
> --
> 2.53.0
>