RE: [PATCH v2 1/2] iommu/vt-d: convert the return type of first_pte_in_page to bool

From: Longpeng (Mike, Cloud Infrastructure Service Product Dept.)
Date: Thu Oct 07 2021 - 07:43:25 EST




> -----Original Message-----
> From: Lu Baolu [mailto:baolu.lu@xxxxxxxxxxxxxxx]
> Sent: Thursday, October 7, 2021 2:18 PM
> To: Longpeng (Mike, Cloud Infrastructure Service Product Dept.)
> <longpeng2@xxxxxxxxxx>; dwmw2@xxxxxxxxxxxxx; will@xxxxxxxxxx;
> joro@xxxxxxxxxx
> Cc: baolu.lu@xxxxxxxxxxxxxxx; iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; Gonglei (Arei) <arei.gonglei@xxxxxxxxxx>
> Subject: Re: [PATCH v2 1/2] iommu/vt-d: convert the return type of
> first_pte_in_page to bool
>
> On 2021/10/5 23:23, Longpeng(Mike) wrote:
> > first_pte_in_page() returns boolean value, so let's convert its
> > return type to bool.
> >
> > Signed-off-by: Longpeng(Mike) <longpeng2@xxxxxxxxxx>
> > ---
> > include/linux/intel-iommu.h | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
> > index 05a65eb..a590b00 100644
> > --- a/include/linux/intel-iommu.h
> > +++ b/include/linux/intel-iommu.h
> > @@ -708,7 +708,7 @@ static inline bool dma_pte_superpage(struct dma_pte *pte)
> > return (pte->val & DMA_PTE_LARGE_PAGE);
> > }
> >
> > -static inline int first_pte_in_page(struct dma_pte *pte)
> > +static inline bool first_pte_in_page(struct dma_pte *pte)
> > {
> > return !((unsigned long)pte & ~VTD_PAGE_MASK);
> > }
> >
>
> Probably,
>
> return IS_ALIGNED((unsigned long)pte, VTD_PAGE_SIZE);
>
> looks neater?
>

Looks better! I'll include this optimization in v3.

> Best regards,
> baolu