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

2021-05-11 Thread Logan Gunthorpe



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


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

2021-05-11 Thread Don Dutile

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 
---
  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 
  #include 
  
-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 

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

2021-05-03 Thread Logan Gunthorpe



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


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

2021-05-02 Thread John Hubbard

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 
---
  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 
  #include 
  
-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,
--
John Hubbard
NVIDIA

  
  	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 

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

2021-04-08 Thread Logan Gunthorpe
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 
---
 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 
 #include 
 
-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