>-----Original Message-----
>From: Duan, Zhenzhong
>Subject: RE: [PATCH 3/5] vfio/iommufd: Add
>IOMMU_HWPT_GET_DIRTY_BITMAP_NO_CLEAR flag support
>>The ugly part of the alternative is that it sort of limits the interface  to 
>>be
>>single-user only as nobody call into IOMMUFD with the dirty_tracking_flags
>if
>>it's called concurrently for some other purpose than unmap. We sort of use
>>the
>>container data structure as a argument storage for a single call as opposed
>to
>>store some intermediary state.
>
>dirty_tracking_flags only take effect during the unmap path except you take it
>for other purpose. But yes, I made the change based on the fact that unmap
>path
>is protected by BQL, if the concurrent access is allowed in future, this change
>will
>break.

I found I misunderstood your comment above. Yes, I planned dirty_tracking_flags
only for unmap usage, not for others. I didn't take it as argument but a 
notification
mechanism only for unmap_all path optimization.

Thanks
Zhenzhong

Reply via email to