Re: [PATCH 2/7] iommu/dma-iommu: Split iommu_dma_map_msi_msg in two parts

[Julien Grall]

Hi,

On 4/23/19 8:08 AM, Christoph Hellwig wrote:
> On Thu, Apr 18, 2019 at 06:26:06PM +0100, Julien Grall wrote:
> > +int iommu_dma_prepare_msi(struct msi_desc *desc, phys_addr_t msi_addr)
> >   {
> > +	struct device *dev = msi_desc_to_dev(desc);
> >   	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
> >   	struct iommu_dma_cookie *cookie;
> >   	unsigned long flags;
> >   
> > +	if (!domain || !domain->iova_cookie) {
> > +		desc->iommu_cookie = NULL;
> > +		return 0;
> > +	}
> >   
> >   	cookie = domain->iova_cookie;
> >   
> > @@ -908,10 +908,33 @@ void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg)
> >   	 * of an MSI from within an IPI handler.
> >   	 */
> >   	spin_lock_irqsave(&cookie->msi_lock, flags);
> > +	desc->iommu_cookie = iommu_dma_get_msi_page(dev, msi_addr, domain);
> >   	spin_unlock_irqrestore(&cookie->msi_lock, flags);
> >   
> > +	return (desc->iommu_cookie) ? 0 : -ENOMEM;
>
> No need for the braces.  Also I personally find a:
>
> 	if (!desc->iommu_cookie)
> 		return -ENOMEM;
> 	return 0;
>
> much more readable, but that might just be personal preference.

I am happy either way. I will use your suggestion in the next version.

Cheers,

--
Julien Grall