On Fri, Aug 23, 2024 at 9:09 AM Will Deacon <will@xxxxxxxxxx> wrote:
>
> On Tue, Aug 20, 2024 at 10:16:44AM -0700, Rob Clark wrote:
> > diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
> > index f5d9fd1f45bf..b4bc358740e0 100644
> > --- a/drivers/iommu/io-pgtable-arm.c
> > +++ b/drivers/iommu/io-pgtable-arm.c
> > @@ -747,33 +747,31 @@ static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
> > }
> >
> > struct io_pgtable_walk_data {
> > - struct iommu_dirty_bitmap *dirty;
> > + void *data;
> > + int (*visit)(struct io_pgtable_walk_data *walk_data, int lvl,
> > + arm_lpae_iopte pte, size_t size);
> > unsigned long flags;
> > u64 addr;
> > const u64 end;
> > };
> >
> > -static int __arm_lpae_iopte_walk_dirty(struct arm_lpae_io_pgtable *data,
> > - struct io_pgtable_walk_data *walk_data,
> > - arm_lpae_iopte *ptep,
> > - int lvl);
> > +static int __arm_lpae_iopte_walk(struct arm_lpae_io_pgtable *data,
> > + struct io_pgtable_walk_data *walk_data,
> > + arm_lpae_iopte *ptep,
> > + int lvl);
> >
> > -static int io_pgtable_visit_dirty(struct arm_lpae_io_pgtable *data,
> > - struct io_pgtable_walk_data *walk_data,
> > - arm_lpae_iopte *ptep, int lvl)
> > +static int io_pgtable_visit(struct arm_lpae_io_pgtable *data,
> > + struct io_pgtable_walk_data *walk_data,
> > + arm_lpae_iopte *ptep, int lvl)
> > {
> > struct io_pgtable *iop = &data->iop;
> > arm_lpae_iopte pte = READ_ONCE(*ptep);
> >
> > if (iopte_leaf(pte, lvl, iop->fmt)) {
> > size_t size = ARM_LPAE_BLOCK_SIZE(lvl, data);
> > -
> > - if (iopte_writeable_dirty(pte)) {
> > - iommu_dirty_bitmap_record(walk_data->dirty,
> > - walk_data->addr, size);
> > - if (!(walk_data->flags & IOMMU_DIRTY_NO_CLEAR))
> > - iopte_set_writeable_clean(ptep);
> > - }
> > + int ret = walk_data->visit(walk_data, lvl, pte, size);
> > + if (ret)
> > + return ret;
> > walk_data->addr += size;
> > return 0;
> > }
> > @@ -782,13 +780,13 @@ static int io_pgtable_visit_dirty(struct arm_lpae_io_pgtable *data,
> > return -EINVAL;
> >
> > ptep = iopte_deref(pte, data);
> > - return __arm_lpae_iopte_walk_dirty(data, walk_data, ptep, lvl + 1);
> > + return __arm_lpae_iopte_walk(data, walk_data, ptep, lvl + 1);
> > }
> >
> > -static int __arm_lpae_iopte_walk_dirty(struct arm_lpae_io_pgtable *data,
> > - struct io_pgtable_walk_data *walk_data,
> > - arm_lpae_iopte *ptep,
> > - int lvl)
> > +static int __arm_lpae_iopte_walk(struct arm_lpae_io_pgtable *data,
> > + struct io_pgtable_walk_data *walk_data,
> > + arm_lpae_iopte *ptep,
> > + int lvl)
> > {
> > u32 idx;
> > int max_entries, ret;
> > @@ -803,7 +801,7 @@ static int __arm_lpae_iopte_walk_dirty(struct arm_lpae_io_pgtable *data,
> >
> > for (idx = ARM_LPAE_LVL_IDX(walk_data->addr, lvl, data);
> > (idx < max_entries) && (walk_data->addr < walk_data->end); ++idx) {
> > - ret = io_pgtable_visit_dirty(data, walk_data, ptep + idx, lvl);
> > + ret = io_pgtable_visit(data, walk_data, ptep + idx, lvl);
> > if (ret)
> > return ret;
> > }
> > @@ -811,6 +809,20 @@ static int __arm_lpae_iopte_walk_dirty(struct arm_lpae_io_pgtable *data,
> > return 0;
> > }
> >
> > +static int visit_dirty(struct io_pgtable_walk_data *walk_data, int lvl,
> > + arm_lpae_iopte pte, size_t size)
> > +{
> > + struct iommu_dirty_bitmap *dirty = walk_data->data;
> > +
> > + if (iopte_writeable_dirty(pte)) {
> > + iommu_dirty_bitmap_record(dirty, walk_data->addr, size);
> > + if (!(walk_data->flags & IOMMU_DIRTY_NO_CLEAR))
> > + iopte_set_writeable_clean(&pte);
>
> Are you sure that's correct? I suspect we really want to update the actual
> page-table in this case, so we probably want to pass the pointer in instead
> of the pte value.
oh, right
> Will
