diff mbox series

[v7,1/4] iommu/io-pgtable-arm: Make pgtable walker more generic

Message ID 20240820171652.145673-2-robdclark@gmail.com (mailing list archive)
State Superseded
Headers show
Series io-pgtable-arm + drm/msm: Extend iova fault debugging | expand

Commit Message

Rob Clark Aug. 20, 2024, 5:16 p.m. UTC 
From: Rob Clark <robdclark@chromium.org>

We can re-use this basic pgtable walk logic in a few places.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/iommu/io-pgtable-arm.c | 59 +++++++++++++++++++++-------------
 1 file changed, 36 insertions(+), 23 deletions(-)

Comments

Will Deacon Aug. 23, 2024, 4:09 p.m. UTC | #1 
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.

Will
Rob Clark Aug. 23, 2024, 5:23 p.m. UTC | #2 
On Fri, Aug 23, 2024 at 9:09 AM Will Deacon <will@kernel.org> 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
diff mbox series

Patch

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);
+	}
+
+	return 0;
+}
+
 static int arm_lpae_read_and_clear_dirty(struct io_pgtable_ops *ops,
 					 unsigned long iova, size_t size,
 					 unsigned long flags,
@@ -819,7 +831,8 @@  static int arm_lpae_read_and_clear_dirty(struct io_pgtable_ops *ops,
 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
 	struct io_pgtable_walk_data walk_data = {
-		.dirty = dirty,
+		.data = dirty,
+		.visit = visit_dirty,
 		.flags = flags,
 		.addr = iova,
 		.end = iova + size,
@@ -834,7 +847,7 @@  static int arm_lpae_read_and_clear_dirty(struct io_pgtable_ops *ops,
 	if (data->iop.fmt != ARM_64_LPAE_S1)
 		return -EINVAL;
 
-	return __arm_lpae_iopte_walk_dirty(data, &walk_data, ptep, lvl);
+	return __arm_lpae_iopte_walk(data, &walk_data, ptep, lvl);
 }
 
 static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)