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| State | Superseded |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