2020-12-23 08:55:13

by Christoph Hellwig

Subject: Re: [PATCH v3 1/7] iommu: Move iotlb_sync_map out from __iommu_map

On Wed, Dec 16, 2020 at 06:36:01PM +0800, Yong Wu wrote:
> In the end of __iommu_map, It alway call iotlb_sync_map.
> This patch moves iotlb_sync_map out from __iommu_map since it is
> unnecessary to call this for each sg segment especially iotlb_sync_map
> is flush tlb all currently.
>
> Signed-off-by: Yong Wu <[email protected]>
> Reviewed-by: Robin Murphy <[email protected]>

What about adding a little helper that does the NULL check and method
call instead of duplicating it all over?

2020-12-24 11:30:26

by Yong Wu (吴勇)

Subject: Re: [PATCH v3 1/7] iommu: Move iotlb_sync_map out from __iommu_map

On Wed, 2020-12-23 at 08:51 +0000, Christoph Hellwig wrote:
> On Wed, Dec 16, 2020 at 06:36:01PM +0800, Yong Wu wrote:
> > In the end of __iommu_map, It alway call iotlb_sync_map.
> > This patch moves iotlb_sync_map out from __iommu_map since it is
> > unnecessary to call this for each sg segment especially iotlb_sync_map
> > is flush tlb all currently.
> >
> > Signed-off-by: Yong Wu <[email protected]>
> > Reviewed-by: Robin Murphy <[email protected]>
>
> What about adding a little helper that does the NULL check and method
> call instead of duplicating it all over?

Thanks for the review. Of course OK.

Then the code like below.
(If the helper name "_iommu_map" is not good, please tell me.)

+static int _iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
+{
+ const struct iommu_ops *ops = domain->ops;
+ int ret;
+
+ ret = __iommu_map(domain, iova, paddr, size, prot, gfp);
+ if (ret == 0 && ops->iotlb_sync_map)
+ ops->iotlb_sync_map(domain);
+ return ret;
+}
+
int iommu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot)
{
might_sleep();
- return __iommu_map(domain, iova, paddr, size, prot, GFP_KERNEL);
+ return _iommu_map(domain, iova, paddr, size, prot, GFP_KERNEL);
}
EXPORT_SYMBOL_GPL(iommu_map);

int iommu_map_atomic(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot)
{
- return __iommu_map(domain, iova, paddr, size, prot, GFP_ATOMIC);
+ return _iommu_map(domain, iova, paddr, size, prot, GFP_ATOMIC);
}
EXPORT_SYMBOL_GPL(iommu_map_atomic);