diff mbox series

[07/16] PCI/P2PDMA: Make pci_p2pdma_map_type() non-static

Message ID 20210408170123.8788-8-logang@deltatee.com (mailing list archive)
State New
Headers show
Series Add new DMA mapping operation for P2PDMA | expand

Commit Message

Logan Gunthorpe April 8, 2021, 5:01 p.m. UTC
pci_p2pdma_map_type() will be needed by the dma-iommu map_sg
implementation because it will need to determine the mapping type
ahead of actually doing the mapping to create the actual iommu mapping.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
---
 drivers/pci/p2pdma.c       | 34 +++++++++++++++++++++++-----------
 include/linux/pci-p2pdma.h | 15 +++++++++++++++
 2 files changed, 38 insertions(+), 11 deletions(-)

Comments

John Hubbard May 2, 2021, 10:44 p.m. UTC | #1
On 4/8/21 10:01 AM, Logan Gunthorpe wrote:
> pci_p2pdma_map_type() will be needed by the dma-iommu map_sg
> implementation because it will need to determine the mapping type
> ahead of actually doing the mapping to create the actual iommu mapping.
> 
> Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
> ---
>   drivers/pci/p2pdma.c       | 34 +++++++++++++++++++++++-----------
>   include/linux/pci-p2pdma.h | 15 +++++++++++++++
>   2 files changed, 38 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
> index bcb1a6d6119d..38c93f57a941 100644
> --- a/drivers/pci/p2pdma.c
> +++ b/drivers/pci/p2pdma.c
> @@ -20,13 +20,6 @@
>   #include <linux/seq_buf.h>
>   #include <linux/xarray.h>
>   
> -enum pci_p2pdma_map_type {
> -	PCI_P2PDMA_MAP_UNKNOWN = 0,
> -	PCI_P2PDMA_MAP_NOT_SUPPORTED,
> -	PCI_P2PDMA_MAP_BUS_ADDR,
> -	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE,
> -};
> -
>   struct pci_p2pdma {
>   	struct gen_pool *pool;
>   	bool p2pmem_published;
> @@ -822,13 +815,30 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
>   }
>   EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
>   
> -static enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
> -						    struct device *dev)
> +/**
> + * pci_p2pdma_map_type - return the type of mapping that should be used for
> + *	a given device and pgmap
> + * @pgmap: the pagemap of a page to determine the mapping type for
> + * @dev: device that is mapping the page
> + * @dma_attrs: the attributes passed to the dma_map operation --
> + *	this is so they can be checked to ensure P2PDMA pages were not
> + *	introduced into an incorrect interface (like dma_map_sg). *
> + *
> + * Returns one of:
> + *	PCI_P2PDMA_MAP_NOT_SUPPORTED - The mapping should not be done
> + *	PCI_P2PDMA_MAP_BUS_ADDR - The mapping should use the PCI bus address
> + *	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE - The mapping should be done directly
> + */
> +enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
> +		struct device *dev, unsigned long dma_attrs)
>   {
>   	struct pci_dev *provider = to_p2p_pgmap(pgmap)->provider;
>   	enum pci_p2pdma_map_type ret;
>   	struct pci_dev *client;
>   
> +	WARN_ONCE(!(dma_attrs & __DMA_ATTR_PCI_P2PDMA),
> +		  "PCI P2PDMA pages were mapped with dma_map_sg!");

This really ought to also return -EINVAL, assuming that my review suggestions
about return types, in earlier patches, are acceptable.

> +
>   	if (!provider->p2pdma)
>   		return PCI_P2PDMA_MAP_NOT_SUPPORTED;
>   
> @@ -879,7 +889,8 @@ int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
>   	struct pci_p2pdma_pagemap *p2p_pgmap =
>   		to_p2p_pgmap(sg_page(sg)->pgmap);
>   
> -	switch (pci_p2pdma_map_type(sg_page(sg)->pgmap, dev)) {
> +	switch (pci_p2pdma_map_type(sg_page(sg)->pgmap, dev,
> +				    __DMA_ATTR_PCI_P2PDMA)) {
>   	case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE:
>   		return dma_map_sg_attrs(dev, sg, nents, dir, attrs);
>   	case PCI_P2PDMA_MAP_BUS_ADDR:
> @@ -904,7 +915,8 @@ void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
>   {
>   	enum pci_p2pdma_map_type map_type;
>   
> -	map_type = pci_p2pdma_map_type(sg_page(sg)->pgmap, dev);
> +	map_type = pci_p2pdma_map_type(sg_page(sg)->pgmap, dev,
> +				       __DMA_ATTR_PCI_P2PDMA);

These areas might end up looking a bit different, if my suggestion about
applying pci_dev type safety throughout are accepted.

The patch looks generally correct, aside from these details.

thanks,
Logan Gunthorpe May 3, 2021, 4:39 p.m. UTC | #2
On 2021-05-02 4:44 p.m., John Hubbard wrote:
> On 4/8/21 10:01 AM, Logan Gunthorpe wrote:
>> pci_p2pdma_map_type() will be needed by the dma-iommu map_sg
>> implementation because it will need to determine the mapping type
>> ahead of actually doing the mapping to create the actual iommu mapping.
>>
>> Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
>> ---
>>   drivers/pci/p2pdma.c       | 34 +++++++++++++++++++++++-----------
>>   include/linux/pci-p2pdma.h | 15 +++++++++++++++
>>   2 files changed, 38 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
>> index bcb1a6d6119d..38c93f57a941 100644
>> --- a/drivers/pci/p2pdma.c
>> +++ b/drivers/pci/p2pdma.c
>> @@ -20,13 +20,6 @@
>>   #include <linux/seq_buf.h>
>>   #include <linux/xarray.h>
>>   
>> -enum pci_p2pdma_map_type {
>> -	PCI_P2PDMA_MAP_UNKNOWN = 0,
>> -	PCI_P2PDMA_MAP_NOT_SUPPORTED,
>> -	PCI_P2PDMA_MAP_BUS_ADDR,
>> -	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE,
>> -};
>> -
>>   struct pci_p2pdma {
>>   	struct gen_pool *pool;
>>   	bool p2pmem_published;
>> @@ -822,13 +815,30 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
>>   }
>>   EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
>>   
>> -static enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
>> -						    struct device *dev)
>> +/**
>> + * pci_p2pdma_map_type - return the type of mapping that should be used for
>> + *	a given device and pgmap
>> + * @pgmap: the pagemap of a page to determine the mapping type for
>> + * @dev: device that is mapping the page
>> + * @dma_attrs: the attributes passed to the dma_map operation --
>> + *	this is so they can be checked to ensure P2PDMA pages were not
>> + *	introduced into an incorrect interface (like dma_map_sg). *
>> + *
>> + * Returns one of:
>> + *	PCI_P2PDMA_MAP_NOT_SUPPORTED - The mapping should not be done
>> + *	PCI_P2PDMA_MAP_BUS_ADDR - The mapping should use the PCI bus address
>> + *	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE - The mapping should be done directly
>> + */
>> +enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
>> +		struct device *dev, unsigned long dma_attrs)
>>   {
>>   	struct pci_dev *provider = to_p2p_pgmap(pgmap)->provider;
>>   	enum pci_p2pdma_map_type ret;
>>   	struct pci_dev *client;
>>   
>> +	WARN_ONCE(!(dma_attrs & __DMA_ATTR_PCI_P2PDMA),
>> +		  "PCI P2PDMA pages were mapped with dma_map_sg!");
> 
> This really ought to also return -EINVAL, assuming that my review suggestions
> about return types, in earlier patches, are acceptable.

That can't happen because, by convention, dma_map_sg() cannot return
-EINVAL. I think the best we can do is proceed normally and just warn
loudly.

Logan
Don Dutile May 11, 2021, 4:06 p.m. UTC | #3
On 4/8/21 1:01 PM, Logan Gunthorpe wrote:
> pci_p2pdma_map_type() will be needed by the dma-iommu map_sg
> implementation because it will need to determine the mapping type
> ahead of actually doing the mapping to create the actual iommu mapping.
>
> Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
> ---
>   drivers/pci/p2pdma.c       | 34 +++++++++++++++++++++++-----------
>   include/linux/pci-p2pdma.h | 15 +++++++++++++++
>   2 files changed, 38 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
> index bcb1a6d6119d..38c93f57a941 100644
> --- a/drivers/pci/p2pdma.c
> +++ b/drivers/pci/p2pdma.c
> @@ -20,13 +20,6 @@
>   #include <linux/seq_buf.h>
>   #include <linux/xarray.h>
>   
> -enum pci_p2pdma_map_type {
> -	PCI_P2PDMA_MAP_UNKNOWN = 0,
> -	PCI_P2PDMA_MAP_NOT_SUPPORTED,
> -	PCI_P2PDMA_MAP_BUS_ADDR,
> -	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE,
> -};
> -
>   struct pci_p2pdma {
>   	struct gen_pool *pool;
>   	bool p2pmem_published;
> @@ -822,13 +815,30 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
>   }
>   EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
>   
> -static enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
> -						    struct device *dev)
> +/**
> + * pci_p2pdma_map_type - return the type of mapping that should be used for
> + *	a given device and pgmap
> + * @pgmap: the pagemap of a page to determine the mapping type for
> + * @dev: device that is mapping the page
> + * @dma_attrs: the attributes passed to the dma_map operation --
> + *	this is so they can be checked to ensure P2PDMA pages were not
> + *	introduced into an incorrect interface (like dma_map_sg). *
> + *
> + * Returns one of:
> + *	PCI_P2PDMA_MAP_NOT_SUPPORTED - The mapping should not be done
> + *	PCI_P2PDMA_MAP_BUS_ADDR - The mapping should use the PCI bus address
> + *	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE - The mapping should be done directly
> + */
I'd recommend putting these descriptions in the enum's in pci-p2pdma.h .
Also, can you use a better description for THRU_HOST_BRIDGE -- it leaves the reader wondering what 'done directly' means.

Thanks.
-dd

> +enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
> +		struct device *dev, unsigned long dma_attrs)
>   {
>   	struct pci_dev *provider = to_p2p_pgmap(pgmap)->provider;
>   	enum pci_p2pdma_map_type ret;
>   	struct pci_dev *client;
>   
> +	WARN_ONCE(!(dma_attrs & __DMA_ATTR_PCI_P2PDMA),
> +		  "PCI P2PDMA pages were mapped with dma_map_sg!");
> +
>   	if (!provider->p2pdma)
>   		return PCI_P2PDMA_MAP_NOT_SUPPORTED;
>   
> @@ -879,7 +889,8 @@ int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
>   	struct pci_p2pdma_pagemap *p2p_pgmap =
>   		to_p2p_pgmap(sg_page(sg)->pgmap);
>   
> -	switch (pci_p2pdma_map_type(sg_page(sg)->pgmap, dev)) {
> +	switch (pci_p2pdma_map_type(sg_page(sg)->pgmap, dev,
> +				    __DMA_ATTR_PCI_P2PDMA)) {
>   	case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE:
>   		return dma_map_sg_attrs(dev, sg, nents, dir, attrs);
>   	case PCI_P2PDMA_MAP_BUS_ADDR:
> @@ -904,7 +915,8 @@ void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
>   {
>   	enum pci_p2pdma_map_type map_type;
>   
> -	map_type = pci_p2pdma_map_type(sg_page(sg)->pgmap, dev);
> +	map_type = pci_p2pdma_map_type(sg_page(sg)->pgmap, dev,
> +				       __DMA_ATTR_PCI_P2PDMA);
>   
>   	if (map_type == PCI_P2PDMA_MAP_THRU_HOST_BRIDGE)
>   		dma_unmap_sg_attrs(dev, sg, nents, dir, attrs);
> diff --git a/include/linux/pci-p2pdma.h b/include/linux/pci-p2pdma.h
> index 8318a97c9c61..a06072ac3a52 100644
> --- a/include/linux/pci-p2pdma.h
> +++ b/include/linux/pci-p2pdma.h
> @@ -16,6 +16,13 @@
>   struct block_device;
>   struct scatterlist;
>   
> +enum pci_p2pdma_map_type {
> +	PCI_P2PDMA_MAP_UNKNOWN = 0,
> +	PCI_P2PDMA_MAP_NOT_SUPPORTED,
> +	PCI_P2PDMA_MAP_BUS_ADDR,
> +	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE,
> +};
> +
>   #ifdef CONFIG_PCI_P2PDMA
>   int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
>   		u64 offset);
> @@ -30,6 +37,8 @@ struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
>   					 unsigned int *nents, u32 length);
>   void pci_p2pmem_free_sgl(struct pci_dev *pdev, struct scatterlist *sgl);
>   void pci_p2pmem_publish(struct pci_dev *pdev, bool publish);
> +enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
> +		struct device *dev, unsigned long dma_attrs);
>   int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
>   		int nents, enum dma_data_direction dir, unsigned long attrs);
>   void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
> @@ -83,6 +92,12 @@ static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev,
>   static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
>   {
>   }
> +static inline enum pci_p2pdma_map_type pci_p2pdma_map_type(
> +		struct dev_pagemap *pgmap, struct device *dev,
> +		unsigned long dma_attrs)
> +{
> +	return PCI_P2PDMA_MAP_NOT_SUPPORTED;
> +}
>   static inline int pci_p2pdma_map_sg_attrs(struct device *dev,
>   		struct scatterlist *sg, int nents, enum dma_data_direction dir,
>   		unsigned long attrs)
Logan Gunthorpe May 11, 2021, 4:17 p.m. UTC | #4
On 2021-05-11 10:06 a.m., Don Dutile wrote:
> On 4/8/21 1:01 PM, Logan Gunthorpe wrote:
>> pci_p2pdma_map_type() will be needed by the dma-iommu map_sg
>> implementation because it will need to determine the mapping type
>> ahead of actually doing the mapping to create the actual iommu mapping.
>>
>> Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
>> ---
>>   drivers/pci/p2pdma.c       | 34 +++++++++++++++++++++++-----------
>>   include/linux/pci-p2pdma.h | 15 +++++++++++++++
>>   2 files changed, 38 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
>> index bcb1a6d6119d..38c93f57a941 100644
>> --- a/drivers/pci/p2pdma.c
>> +++ b/drivers/pci/p2pdma.c
>> @@ -20,13 +20,6 @@
>>   #include <linux/seq_buf.h>
>>   #include <linux/xarray.h>
>>   
>> -enum pci_p2pdma_map_type {
>> -	PCI_P2PDMA_MAP_UNKNOWN = 0,
>> -	PCI_P2PDMA_MAP_NOT_SUPPORTED,
>> -	PCI_P2PDMA_MAP_BUS_ADDR,
>> -	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE,
>> -};
>> -
>>   struct pci_p2pdma {
>>   	struct gen_pool *pool;
>>   	bool p2pmem_published;
>> @@ -822,13 +815,30 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
>>   }
>>   EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
>>   
>> -static enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
>> -						    struct device *dev)
>> +/**
>> + * pci_p2pdma_map_type - return the type of mapping that should be used for
>> + *	a given device and pgmap
>> + * @pgmap: the pagemap of a page to determine the mapping type for
>> + * @dev: device that is mapping the page
>> + * @dma_attrs: the attributes passed to the dma_map operation --
>> + *	this is so they can be checked to ensure P2PDMA pages were not
>> + *	introduced into an incorrect interface (like dma_map_sg). *
>> + *
>> + * Returns one of:
>> + *	PCI_P2PDMA_MAP_NOT_SUPPORTED - The mapping should not be done
>> + *	PCI_P2PDMA_MAP_BUS_ADDR - The mapping should use the PCI bus address
>> + *	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE - The mapping should be done directly
>> + */
> I'd recommend putting these descriptions in the enum's in pci-p2pdma.h .
> Also, can you use a better description for THRU_HOST_BRIDGE -- it leaves the reader wondering what 'done directly' means.

Will do.

Logan
diff mbox series

Patch

diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
index bcb1a6d6119d..38c93f57a941 100644
--- a/drivers/pci/p2pdma.c
+++ b/drivers/pci/p2pdma.c
@@ -20,13 +20,6 @@ 
 #include <linux/seq_buf.h>
 #include <linux/xarray.h>
 
-enum pci_p2pdma_map_type {
-	PCI_P2PDMA_MAP_UNKNOWN = 0,
-	PCI_P2PDMA_MAP_NOT_SUPPORTED,
-	PCI_P2PDMA_MAP_BUS_ADDR,
-	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE,
-};
-
 struct pci_p2pdma {
 	struct gen_pool *pool;
 	bool p2pmem_published;
@@ -822,13 +815,30 @@  void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
 }
 EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
 
-static enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
-						    struct device *dev)
+/**
+ * pci_p2pdma_map_type - return the type of mapping that should be used for
+ *	a given device and pgmap
+ * @pgmap: the pagemap of a page to determine the mapping type for
+ * @dev: device that is mapping the page
+ * @dma_attrs: the attributes passed to the dma_map operation --
+ *	this is so they can be checked to ensure P2PDMA pages were not
+ *	introduced into an incorrect interface (like dma_map_sg). *
+ *
+ * Returns one of:
+ *	PCI_P2PDMA_MAP_NOT_SUPPORTED - The mapping should not be done
+ *	PCI_P2PDMA_MAP_BUS_ADDR - The mapping should use the PCI bus address
+ *	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE - The mapping should be done directly
+ */
+enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
+		struct device *dev, unsigned long dma_attrs)
 {
 	struct pci_dev *provider = to_p2p_pgmap(pgmap)->provider;
 	enum pci_p2pdma_map_type ret;
 	struct pci_dev *client;
 
+	WARN_ONCE(!(dma_attrs & __DMA_ATTR_PCI_P2PDMA),
+		  "PCI P2PDMA pages were mapped with dma_map_sg!");
+
 	if (!provider->p2pdma)
 		return PCI_P2PDMA_MAP_NOT_SUPPORTED;
 
@@ -879,7 +889,8 @@  int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 	struct pci_p2pdma_pagemap *p2p_pgmap =
 		to_p2p_pgmap(sg_page(sg)->pgmap);
 
-	switch (pci_p2pdma_map_type(sg_page(sg)->pgmap, dev)) {
+	switch (pci_p2pdma_map_type(sg_page(sg)->pgmap, dev,
+				    __DMA_ATTR_PCI_P2PDMA)) {
 	case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE:
 		return dma_map_sg_attrs(dev, sg, nents, dir, attrs);
 	case PCI_P2PDMA_MAP_BUS_ADDR:
@@ -904,7 +915,8 @@  void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
 {
 	enum pci_p2pdma_map_type map_type;
 
-	map_type = pci_p2pdma_map_type(sg_page(sg)->pgmap, dev);
+	map_type = pci_p2pdma_map_type(sg_page(sg)->pgmap, dev,
+				       __DMA_ATTR_PCI_P2PDMA);
 
 	if (map_type == PCI_P2PDMA_MAP_THRU_HOST_BRIDGE)
 		dma_unmap_sg_attrs(dev, sg, nents, dir, attrs);
diff --git a/include/linux/pci-p2pdma.h b/include/linux/pci-p2pdma.h
index 8318a97c9c61..a06072ac3a52 100644
--- a/include/linux/pci-p2pdma.h
+++ b/include/linux/pci-p2pdma.h
@@ -16,6 +16,13 @@ 
 struct block_device;
 struct scatterlist;
 
+enum pci_p2pdma_map_type {
+	PCI_P2PDMA_MAP_UNKNOWN = 0,
+	PCI_P2PDMA_MAP_NOT_SUPPORTED,
+	PCI_P2PDMA_MAP_BUS_ADDR,
+	PCI_P2PDMA_MAP_THRU_HOST_BRIDGE,
+};
+
 #ifdef CONFIG_PCI_P2PDMA
 int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
 		u64 offset);
@@ -30,6 +37,8 @@  struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
 					 unsigned int *nents, u32 length);
 void pci_p2pmem_free_sgl(struct pci_dev *pdev, struct scatterlist *sgl);
 void pci_p2pmem_publish(struct pci_dev *pdev, bool publish);
+enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap,
+		struct device *dev, unsigned long dma_attrs);
 int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 		int nents, enum dma_data_direction dir, unsigned long attrs);
 void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
@@ -83,6 +92,12 @@  static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev,
 static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
 {
 }
+static inline enum pci_p2pdma_map_type pci_p2pdma_map_type(
+		struct dev_pagemap *pgmap, struct device *dev,
+		unsigned long dma_attrs)
+{
+	return PCI_P2PDMA_MAP_NOT_SUPPORTED;
+}
 static inline int pci_p2pdma_map_sg_attrs(struct device *dev,
 		struct scatterlist *sg, int nents, enum dma_data_direction dir,
 		unsigned long attrs)