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

[Alex Williamson <alex.williamson@redhat.com>]

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

> From: Li Zhe <lizhe.67@bytedance.com>
> 
> 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@bytedance.com>
> ---
>  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: