Re: [PATCH v6 05/15] swiotlb: Add a new get_io_tlb_mem getter

[Claire Chang]

On Mon, May 10, 2021 at 11:03 PM Christoph Hellwig  wrote:
>
> > +static inline struct io_tlb_mem *get_io_tlb_mem(struct device *dev)
> > +{
> > +#ifdef CONFIG_DMA_RESTRICTED_POOL
> > + if (dev && dev->dma_io_tlb_mem)
> > + return dev->dma_io_tlb_mem;
> > +#endif /* CONFIG_DMA_RESTRICTED_POOL */
> > +
> > + return io_tlb_default_mem;
>
> Given that we're also looking into a not addressing restricted pool
> I'd rather always assign the active pool to dev->dma_io_tlb_mem and
> do away with this helper.

Where do you think is the proper place to do the assignment? First
time calling swiotlb_map? or in of_dma_configure_id?
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

Re: [PATCH v6 05/15] swiotlb: Add a new get_io_tlb_mem getter

[Christoph Hellwig]

> +static inline struct io_tlb_mem *get_io_tlb_mem(struct device *dev)
> +{
> +#ifdef CONFIG_DMA_RESTRICTED_POOL
> + if (dev && dev->dma_io_tlb_mem)
> + return dev->dma_io_tlb_mem;
> +#endif /* CONFIG_DMA_RESTRICTED_POOL */
> +
> + return io_tlb_default_mem;

Given that we're also looking into a not addressing restricted pool
I'd rather always assign the active pool to dev->dma_io_tlb_mem and
do away with this helper.
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

[PATCH v6 05/15] swiotlb: Add a new get_io_tlb_mem getter

[Claire Chang]

Add a new getter, get_io_tlb_mem, to help select the io_tlb_mem struct.
The restricted DMA pool is preferred if available.

Signed-off-by: Claire Chang 
---
 include/linux/swiotlb.h | 11 +++
 1 file changed, 11 insertions(+)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 03ad6e3b4056..b469f04cca26 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -2,6 +2,7 @@
 #ifndef __LINUX_SWIOTLB_H
 #define __LINUX_SWIOTLB_H
 
+#include 
 #include 
 #include 
 #include 
@@ -102,6 +103,16 @@ struct io_tlb_mem {
 };
 extern struct io_tlb_mem *io_tlb_default_mem;
 
+static inline struct io_tlb_mem *get_io_tlb_mem(struct device *dev)
+{
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+   if (dev && dev->dma_io_tlb_mem)
+   return dev->dma_io_tlb_mem;
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
+
+   return io_tlb_default_mem;
+}
+
 static inline bool is_swiotlb_buffer(phys_addr_t paddr)
 {
struct io_tlb_mem *mem = io_tlb_default_mem;
-- 
2.31.1.607.g51e8a6a459-goog

___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu