Re: [PATCH v3 5/7] iommu: Allow io_pgtable_tlb ops optional

[Robin Murphy]

On 2020-12-16 10:36, Yong Wu wrote:
This patch allows io_pgtable_tlb ops could be null since the IOMMU drivers
may use the tlb ops from iommu framework.

There's not much in it, but I guess this does make more sense overall 
than just making .tlb_flush_all optional and drivers having to provide a 
full set of NULL callbacks.

Reviewed-by: Robin Murphy <robin.mur...@arm.com>

Signed-off-by: Yong Wu <yong...@mediatek.com>
---
  include/linux/io-pgtable.h | 8 +++++---
  1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index adde9e49be08..c81796814afa 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -206,14 +206,16 @@ struct io_pgtable {
  
  static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
  {
-       iop->cfg.tlb->tlb_flush_all(iop->cookie);
+       if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_all)
+               iop->cfg.tlb->tlb_flush_all(iop->cookie);
  }
  
  static inline void
  io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
                          size_t size, size_t granule)
  {
-       iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
+       if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_walk)
+               iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
  }
  
  static inline void
@@ -221,7 +223,7 @@ io_pgtable_tlb_add_page(struct io_pgtable *iop,
                        struct iommu_iotlb_gather * gather, unsigned long iova,
                        size_t granule)
  {
-       if (iop->cfg.tlb->tlb_add_page)
+       if (iop->cfg.tlb && iop->cfg.tlb->tlb_add_page)
                iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
  }