Re: [PATCH 2/4] vfio: vfio_pci_nvlink2: use mmgrab

From: Alex Williamson
Date: Mon Jan 06 2020 - 18:05:13 EST


On Sun, 29 Dec 2019 16:42:56 +0100
Julia Lawall <Julia.Lawall@xxxxxxxx> wrote:

> Mmgrab was introduced in commit f1f1007644ff ("mm: add new mmgrab()
> helper") and most of the kernel was updated to use it. Update a
> remaining file.
>
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
>
> <smpl>
> @@ expression e; @@
> - atomic_inc(&e->mm_count);
> + mmgrab(e);
> </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxxx>
>
> ---
> drivers/vfio/pci/vfio_pci_nvlink2.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/pci/vfio_pci_nvlink2.c b/drivers/vfio/pci/vfio_pci_nvlink2.c
> index f2983f0f84be..43df10af7f66 100644
> --- a/drivers/vfio/pci/vfio_pci_nvlink2.c
> +++ b/drivers/vfio/pci/vfio_pci_nvlink2.c
> @@ -159,7 +159,7 @@ static int vfio_pci_nvgpu_mmap(struct vfio_pci_device *vdev,
> data->useraddr = vma->vm_start;
> data->mm = current->mm;
>
> - atomic_inc(&data->mm->mm_count);
> + mmgrab(data->mm);
> ret = (int) mm_iommu_newdev(data->mm, data->useraddr,
> vma_pages(vma), data->gpu_hpa, &data->mem);
>
>

Acked-by: Alex Williamson <alex.williamson@xxxxxxxxxx>

Thanks! I'm assuming these will be routed via janitors tree, please
let me know if you intend me to grab these two vfio patches from the
series. Thanks,

Alex