diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c index 1e59df041456fc35b01033cf3997a90a5e510735..fe21a5c557e65c47c11ac50eba29c409619b58fa 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 e87196cc1a7fba33d37661ad0f73ca1dd1418583..ab2b8bcd29bfc62f471bae0fb1a827704de75748 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -6033,7 +6033,9 @@ 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) @@ -6057,6 +6059,21 @@ 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 bade14002fd8ad9afa5f3910458d4b3fcd9ea924..efdb8b56035fa1184e964a91bd3e895b77bfa6ca 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 c393dff2d66f6c28834a9f4e3416f51bcc10dc7b..7f4e806669728f7c7004ce74d27e4b4fc56e89ef 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1202,6 +1202,7 @@ int __must_check pci_resize_resource(struct pci_dev *dev, int i, int size); 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,