| Message ID | 1579613871-301529-4-git-send-email-jonathan.derrick@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | Clean up VMD DMA Map Ops | expand |
On Tue, Jan 21, 2020 at 06:37:47AM -0700, Jon Derrick wrote: > The current DMA alias implementation requires the aliased device be on > the same PCI bus as the requester ID. This introduces an arch-specific > mechanism to point to another PCI device when doing mapping and > PCI DMA alias search. The default case returns the actual device. > > CC: Christoph Hellwig <hch@lst.de> > Signed-off-by: Jon Derrick <jonathan.derrick@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Looks like a nice cleanup to me. Lorenzo, let me know if you want me to take this. > --- > arch/x86/pci/common.c | 10 ++++++++++ > drivers/pci/pci.c | 19 ++++++++++++++++++- > drivers/pci/search.c | 6 ++++++ > include/linux/pci.h | 1 + > 4 files changed, 35 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c > index 1e59df0..fe21a5c 100644 > --- a/arch/x86/pci/common.c > +++ b/arch/x86/pci/common.c > @@ -736,3 +736,13 @@ int pci_ext_cfg_avail(void) > else > return 0; > } > + > +#if IS_ENABLED(CONFIG_VMD) > +struct pci_dev *pci_real_dma_dev(struct pci_dev *dev) > +{ > + if (is_vmd(dev->bus)) > + return to_pci_sysdata(dev->bus)->vmd_dev; > + > + return dev; > +} > +#endif > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index 581b177..36d24f2 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -6048,7 +6048,9 @@ bool pci_devs_are_dma_aliases(struct pci_dev *dev1, struct pci_dev *dev2) > return (dev1->dma_alias_mask && > test_bit(dev2->devfn, dev1->dma_alias_mask)) || > (dev2->dma_alias_mask && > - test_bit(dev1->devfn, dev2->dma_alias_mask)); > + test_bit(dev1->devfn, dev2->dma_alias_mask)) || > + pci_real_dma_dev(dev1) == dev2 || > + pci_real_dma_dev(dev2) == dev1; > } > > bool pci_device_is_present(struct pci_dev *pdev) > @@ -6072,6 +6074,21 @@ void pci_ignore_hotplug(struct pci_dev *dev) > } > EXPORT_SYMBOL_GPL(pci_ignore_hotplug); > > +/** > + * pci_real_dma_dev - Get PCI DMA device for PCI device > + * @dev: the PCI device that may have a PCI DMA alias > + * > + * Permits the platform to provide architecture-specific functionality to > + * devices needing to alias DMA to another PCI device on another PCI bus. If > + * the PCI device is on the same bus, it is recommended to use > + * pci_add_dma_alias(). This is the default implementation. Architecture > + * implementations can override this. > + */ > +struct pci_dev __weak *pci_real_dma_dev(struct pci_dev *dev) > +{ > + return dev; > +} > + > resource_size_t __weak pcibios_default_alignment(void) > { > return 0; > diff --git a/drivers/pci/search.c b/drivers/pci/search.c > index e4dbdef..2061672 100644 > --- a/drivers/pci/search.c > +++ b/drivers/pci/search.c > @@ -32,6 +32,12 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, > struct pci_bus *bus; > int ret; > > + /* > + * The device may have an explicit alias requester ID for DMA where the > + * requester is on another PCI bus. > + */ > + pdev = pci_real_dma_dev(pdev); > ret = fn(pdev, pci_dev_id(pdev), data); > if (ret) > return ret; > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 930fab2..3840a54 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -1202,6 +1202,7 @@ u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev, > int pci_select_bars(struct pci_dev *dev, unsigned long flags); > bool pci_device_is_present(struct pci_dev *pdev); > void pci_ignore_hotplug(struct pci_dev *dev); > +struct pci_dev *pci_real_dma_dev(struct pci_dev *dev); > > int __printf(6, 7) pci_request_irq(struct pci_dev *dev, unsigned int nr, > irq_handler_t handler, irq_handler_t thread_fn, void *dev_id, > -- > 1.8.3.1 >
On Wed, Jan 22, 2020 at 03:12:59PM -0600, Bjorn Helgaas wrote: > On Tue, Jan 21, 2020 at 06:37:47AM -0700, Jon Derrick wrote: > > The current DMA alias implementation requires the aliased device be on > > the same PCI bus as the requester ID. This introduces an arch-specific > > mechanism to point to another PCI device when doing mapping and > > PCI DMA alias search. The default case returns the actual device. > > > > CC: Christoph Hellwig <hch@lst.de> > > Signed-off-by: Jon Derrick <jonathan.derrick@intel.com> > > Acked-by: Bjorn Helgaas <bhelgaas@google.com> > > Looks like a nice cleanup to me. > > Lorenzo, let me know if you want me to take this. Hi Bjorn, I think it makes sense for you to take the series given that it is mostly core/x86 changes. FWIW I Acked the relevant patch (6) even though Jon forgot to carry it to v5. Thanks, Lorenzo > > arch/x86/pci/common.c | 10 ++++++++++ > > drivers/pci/pci.c | 19 ++++++++++++++++++- > > drivers/pci/search.c | 6 ++++++ > > include/linux/pci.h | 1 + > > 4 files changed, 35 insertions(+), 1 deletion(-) > > > > diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c > > index 1e59df0..fe21a5c 100644 > > --- a/arch/x86/pci/common.c > > +++ b/arch/x86/pci/common.c > > @@ -736,3 +736,13 @@ int pci_ext_cfg_avail(void) > > else > > return 0; > > } > > + > > +#if IS_ENABLED(CONFIG_VMD) > > +struct pci_dev *pci_real_dma_dev(struct pci_dev *dev) > > +{ > > + if (is_vmd(dev->bus)) > > + return to_pci_sysdata(dev->bus)->vmd_dev; > > + > > + return dev; > > +} > > +#endif > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > > index 581b177..36d24f2 100644 > > --- a/drivers/pci/pci.c > > +++ b/drivers/pci/pci.c > > @@ -6048,7 +6048,9 @@ bool pci_devs_are_dma_aliases(struct pci_dev *dev1, struct pci_dev *dev2) > > return (dev1->dma_alias_mask && > > test_bit(dev2->devfn, dev1->dma_alias_mask)) || > > (dev2->dma_alias_mask && > > - test_bit(dev1->devfn, dev2->dma_alias_mask)); > > + test_bit(dev1->devfn, dev2->dma_alias_mask)) || > > + pci_real_dma_dev(dev1) == dev2 || > > + pci_real_dma_dev(dev2) == dev1; > > } > > > > bool pci_device_is_present(struct pci_dev *pdev) > > @@ -6072,6 +6074,21 @@ void pci_ignore_hotplug(struct pci_dev *dev) > > } > > EXPORT_SYMBOL_GPL(pci_ignore_hotplug); > > > > +/** > > + * pci_real_dma_dev - Get PCI DMA device for PCI device > > + * @dev: the PCI device that may have a PCI DMA alias > > + * > > + * Permits the platform to provide architecture-specific functionality to > > + * devices needing to alias DMA to another PCI device on another PCI bus. If > > + * the PCI device is on the same bus, it is recommended to use > > + * pci_add_dma_alias(). This is the default implementation. Architecture > > + * implementations can override this. > > + */ > > +struct pci_dev __weak *pci_real_dma_dev(struct pci_dev *dev) > > +{ > > + return dev; > > +} > > + > > resource_size_t __weak pcibios_default_alignment(void) > > { > > return 0; > > diff --git a/drivers/pci/search.c b/drivers/pci/search.c > > index e4dbdef..2061672 100644 > > --- a/drivers/pci/search.c > > +++ b/drivers/pci/search.c > > @@ -32,6 +32,12 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, > > struct pci_bus *bus; > > int ret; > > > > + /* > > + * The device may have an explicit alias requester ID for DMA where the > > + * requester is on another PCI bus. > > + */ > > + pdev = pci_real_dma_dev(pdev); > > ret = fn(pdev, pci_dev_id(pdev), data); > > if (ret) > > return ret; > > diff --git a/include/linux/pci.h b/include/linux/pci.h > > index 930fab2..3840a54 100644 > > --- a/include/linux/pci.h > > +++ b/include/linux/pci.h > > @@ -1202,6 +1202,7 @@ u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev, > > int pci_select_bars(struct pci_dev *dev, unsigned long flags); > > bool pci_device_is_present(struct pci_dev *pdev); > > void pci_ignore_hotplug(struct pci_dev *dev); > > +struct pci_dev *pci_real_dma_dev(struct pci_dev *dev); > > > > int __printf(6, 7) pci_request_irq(struct pci_dev *dev, unsigned int nr, > > irq_handler_t handler, irq_handler_t thread_fn, void *dev_id, > > -- > > 1.8.3.1 > >
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c index 1e59df0..fe21a5c 100644 --- a/arch/x86/pci/common.c +++ b/arch/x86/pci/common.c @@ -736,3 +736,13 @@ int pci_ext_cfg_avail(void) else return 0; } + +#if IS_ENABLED(CONFIG_VMD) +struct pci_dev *pci_real_dma_dev(struct pci_dev *dev) +{ + if (is_vmd(dev->bus)) + return to_pci_sysdata(dev->bus)->vmd_dev; + + return dev; +} +#endif diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 581b177..36d24f2 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -6048,7 +6048,9 @@ bool pci_devs_are_dma_aliases(struct pci_dev *dev1, struct pci_dev *dev2) return (dev1->dma_alias_mask && test_bit(dev2->devfn, dev1->dma_alias_mask)) || (dev2->dma_alias_mask && - test_bit(dev1->devfn, dev2->dma_alias_mask)); + test_bit(dev1->devfn, dev2->dma_alias_mask)) || + pci_real_dma_dev(dev1) == dev2 || + pci_real_dma_dev(dev2) == dev1; } bool pci_device_is_present(struct pci_dev *pdev) @@ -6072,6 +6074,21 @@ void pci_ignore_hotplug(struct pci_dev *dev) } EXPORT_SYMBOL_GPL(pci_ignore_hotplug); +/** + * pci_real_dma_dev - Get PCI DMA device for PCI device + * @dev: the PCI device that may have a PCI DMA alias + * + * Permits the platform to provide architecture-specific functionality to + * devices needing to alias DMA to another PCI device on another PCI bus. If + * the PCI device is on the same bus, it is recommended to use + * pci_add_dma_alias(). This is the default implementation. Architecture + * implementations can override this. + */ +struct pci_dev __weak *pci_real_dma_dev(struct pci_dev *dev) +{ + return dev; +} + resource_size_t __weak pcibios_default_alignment(void) { return 0; diff --git a/drivers/pci/search.c b/drivers/pci/search.c index e4dbdef..2061672 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -32,6 +32,12 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, struct pci_bus *bus; int ret; + /* + * The device may have an explicit alias requester ID for DMA where the + * requester is on another PCI bus. + */ + pdev = pci_real_dma_dev(pdev); + ret = fn(pdev, pci_dev_id(pdev), data); if (ret) return ret; diff --git a/include/linux/pci.h b/include/linux/pci.h index 930fab2..3840a54 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1202,6 +1202,7 @@ u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev, int pci_select_bars(struct pci_dev *dev, unsigned long flags); bool pci_device_is_present(struct pci_dev *pdev); void pci_ignore_hotplug(struct pci_dev *dev); +struct pci_dev *pci_real_dma_dev(struct pci_dev *dev); int __printf(6, 7) pci_request_irq(struct pci_dev *dev, unsigned int nr, irq_handler_t handler, irq_handler_t thread_fn, void *dev_id,
The current DMA alias implementation requires the aliased device be on the same PCI bus as the requester ID. This introduces an arch-specific mechanism to point to another PCI device when doing mapping and PCI DMA alias search. The default case returns the actual device. CC: Christoph Hellwig <hch@lst.de> Signed-off-by: Jon Derrick <jonathan.derrick@intel.com> --- arch/x86/pci/common.c | 10 ++++++++++ drivers/pci/pci.c | 19 ++++++++++++++++++- drivers/pci/search.c | 6 ++++++ include/linux/pci.h | 1 + 4 files changed, 35 insertions(+), 1 deletion(-)