Re: [PATCH v5 2/3] vfio/type1: introduce a new member has_rsvd for struct vfio_dma

From: Alex Williamson
Date: Fri Jun 27 2025 - 17:40:23 EST


On Fri, 20 Jun 2025 11:23:43 +0800
lizhe.67@xxxxxxxxxxxxx wrote:

> From: Li Zhe <lizhe.67@xxxxxxxxxxxxx>
>
> Introduce a new member has_rsvd for struct vfio_dma. This member is
> used to indicate whether there are any reserved or invalid pfns in
> the region represented by this vfio_dma. If it is true, it indicates
> that there is at least one pfn in this region that is either reserved
> or invalid.
>
> Signed-off-by: Li Zhe <lizhe.67@xxxxxxxxxxxxx>
> ---
> drivers/vfio/vfio_iommu_type1.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index e952bf8bdfab..8827e315e3d8 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -93,6 +93,10 @@ struct vfio_dma {
> bool iommu_mapped;
> bool lock_cap; /* capable(CAP_IPC_LOCK) */
> bool vaddr_invalid;
> + /*
> + * Any reserved or invalid pfns within this range?
> + */
> + bool has_rsvd;

Nit, the topic isn't so complex to make a brief comment:

bool has_rsvd; /* has 1 or more rsvd pfns */

Thanks,
Alex

> struct task_struct *task;
> struct rb_root pfn_list; /* Ex-user pinned pfn list */
> unsigned long *bitmap;
> @@ -785,6 +789,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr,
> }
>
> out:
> + dma->has_rsvd |= rsvd;
> ret = vfio_lock_acct(dma, lock_acct, false);
>
> unpin_out: