On Fri, Aug 23, 2024 at 9:11 AM Will Deacon <will@xxxxxxxxxx> wrote:
>
> On Tue, Aug 20, 2024 at 10:16:45AM -0700, Rob Clark wrote:
> > From: Rob Clark <robdclark@xxxxxxxxxxxx>
> >
> > Re-use the generic pgtable walk path.
> >
> > Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
> > ---
> > drivers/iommu/io-pgtable-arm.c | 73 +++++++++++++++++-----------------
> > 1 file changed, 36 insertions(+), 37 deletions(-)
> >
> > diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
> > index b4bc358740e0..5fa1274a665a 100644
> > --- a/drivers/iommu/io-pgtable-arm.c
> > +++ b/drivers/iommu/io-pgtable-arm.c
> > @@ -710,42 +710,6 @@ static size_t arm_lpae_unmap_pages(struct io_pgtable_ops *ops, unsigned long iov
> > data->start_level, ptep);
> > }
> >
> > -static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
> > - unsigned long iova)
> > -{
> > - struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
> > - arm_lpae_iopte pte, *ptep = data->pgd;
> > - int lvl = data->start_level;
> > -
> > - do {
> > - /* Valid IOPTE pointer? */
> > - if (!ptep)
> > - return 0;
> > -
> > - /* Grab the IOPTE we're interested in */
> > - ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
> > - pte = READ_ONCE(*ptep);
> > -
> > - /* Valid entry? */
> > - if (!pte)
> > - return 0;
> > -
> > - /* Leaf entry? */
> > - if (iopte_leaf(pte, lvl, data->iop.fmt))
> > - goto found_translation;
> > -
> > - /* Take it to the next level */
> > - ptep = iopte_deref(pte, data);
> > - } while (++lvl < ARM_LPAE_MAX_LEVELS);
> > -
> > - /* Ran out of page tables to walk */
> > - return 0;
> > -
> > -found_translation:
> > - iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1);
> > - return iopte_to_paddr(pte, data) | iova;
> > -}
> > -
> > struct io_pgtable_walk_data {
> > void *data;
> > int (*visit)(struct io_pgtable_walk_data *walk_data, int lvl,
> > @@ -760,6 +724,41 @@ static int __arm_lpae_iopte_walk(struct arm_lpae_io_pgtable *data,
> > arm_lpae_iopte *ptep,
> > int lvl);
> >
> > +struct iova_to_phys_data {
> > + arm_lpae_iopte pte;
> > + int lvl;
> > +};
> > +
> > +static int visit_iova_to_phys(struct io_pgtable_walk_data *walk_data, int lvl,
> > + arm_lpae_iopte pte, size_t size)
> > +{
> > + struct iova_to_phys_data *data = walk_data->data;
> > + data->pte = pte;
> > + data->lvl = lvl;
> > + return 0;
> > +}
> > +
> > +static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
> > + unsigned long iova)
> > +{
> > + struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
> > + struct iova_to_phys_data d;
> > + struct io_pgtable_walk_data walk_data = {
> > + .data = &d,
> > + .visit = visit_iova_to_phys,
> > + .addr = iova,
> > + .end = iova + 1,
> > + };
> > + int ret;
> > +
> > + ret = __arm_lpae_iopte_walk(data, &walk_data, data->pgd, data->start_level);
> > + if (ret)
> > + return 0;
> > +
> > + iova &= (ARM_LPAE_BLOCK_SIZE(d.lvl, data) - 1);
> > + return iopte_to_paddr(d.pte, data) | iova;
> > +}
> > +
> > static int io_pgtable_visit(struct arm_lpae_io_pgtable *data,
> > struct io_pgtable_walk_data *walk_data,
> > arm_lpae_iopte *ptep, int lvl)
> > @@ -776,7 +775,7 @@ static int io_pgtable_visit(struct arm_lpae_io_pgtable *data,
> > return 0;
> > }
> >
> > - if (WARN_ON(!iopte_table(pte, lvl)))
> > + if (WARN_ON(!iopte_table(pte, lvl) && !selftest_running))
>
> Why do you care about the selftest here?
Otherwise we see a flood of WARN_ON from negative tests in the selftests
BR,
-R
> Will
