On Tue, Nov 24, 2020 at 05:24:44PM +0800, Yong Wu wrote:
> On Mon, 2020-11-23 at 12:32 +0000, Will Deacon wrote:
> > On Fri, Nov 20, 2020 at 05:06:28PM +0800, Yong Wu wrote:
> > > + unmapped_sz = 0;
> > > + }
> > > + start += pg_size;
> > > + }
> > > + if (unmapped_sz) {
> > > + ret = iommu_map(domain, start, start, unmapped_sz,
> > > + entry->prot);
> >
> > Can you avoid this hunk by changing your loop check to something like:
> >
> > if (!phys_addr) {
> > map_size += pg_size;
> > if (addr + pg_size < end)
> > continue;
> > }
>
> Thanks for your quick review. I have fixed and tested it. the patch is
> simple. I copy it here. Is this readable for you now?
>
>
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -737,6 +737,7 @@ static int
> iommu_create_device_direct_mappings(struct iommu_group *group,
> /* We need to consider overlapping regions for different devices */
> list_for_each_entry(entry, &mappings, list) {
> dma_addr_t start, end, addr;
> + size_t map_size = 0;
>
> if (domain->ops->apply_resv_region)
> domain->ops->apply_resv_region(dev, domain, entry);
> @@ -752,12 +753,21 @@ static int
> iommu_create_device_direct_mappings(struct iommu_group *group,
> phys_addr_t phys_addr;
>
> phys_addr = iommu_iova_to_phys(domain, addr);
> - if (phys_addr)
> - continue;
> + if (!phys_addr) {
> + map_size += pg_size;
> + if (addr + pg_size < end)
> + continue;
> + else
You don't need the 'else' here ^^^
> + addr += pg_size; /*Point to End */
addr = end ?
That said, maybe we could simplify this further by changing the loop bounds
to be:
for (addr = start; addr <= end; addr += pg_size)
and checking:
if (!phys_addr && addr != end) {
map_size += pg_size;
continue;
}
does that work?
Will
