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-rw-r--r--drivers/pci/quirks.c51
-rw-r--r--include/linux/pci.h8
2 files changed, 59 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 2a7521677541..acd3956b44bd 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3179,3 +3179,54 @@ int pci_dev_specific_reset(struct pci_dev *dev, int probe)
return -ENOTTY;
}
+
+static struct pci_dev *pci_func_0_dma_source(struct pci_dev *dev)
+{
+ if (!PCI_FUNC(dev->devfn))
+ return pci_dev_get(dev);
+
+ return pci_get_slot(dev->bus, PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
+}
+
+static const struct pci_dev_dma_source {
+ u16 vendor;
+ u16 device;
+ struct pci_dev *(*dma_source)(struct pci_dev *dev);
+} pci_dev_dma_source[] = {
+ /*
+ * https://bugzilla.redhat.com/show_bug.cgi?id=605888
+ *
+ * Some Ricoh devices use the function 0 source ID for DMA on
+ * other functions of a multifunction device. The DMA devices
+ * is therefore function 0, which will have implications of the
+ * iommu grouping of these devices.
+ */
+ { PCI_VENDOR_ID_RICOH, 0xe822, pci_func_0_dma_source },
+ { PCI_VENDOR_ID_RICOH, 0xe230, pci_func_0_dma_source },
+ { PCI_VENDOR_ID_RICOH, 0xe832, pci_func_0_dma_source },
+ { PCI_VENDOR_ID_RICOH, 0xe476, pci_func_0_dma_source },
+ { 0 }
+};
+
+/*
+ * IOMMUs with isolation capabilities need to be programmed with the
+ * correct source ID of a device. In most cases, the source ID matches
+ * the device doing the DMA, but sometimes hardware is broken and will
+ * tag the DMA as being sourced from a different device. This function
+ * allows that translation. Note that the reference count of the
+ * returned device is incremented on all paths.
+ */
+struct pci_dev *pci_get_dma_source(struct pci_dev *dev)
+{
+ const struct pci_dev_dma_source *i;
+
+ for (i = pci_dev_dma_source; i->dma_source; i++) {
+ if ((i->vendor == dev->vendor ||
+ i->vendor == (u16)PCI_ANY_ID) &&
+ (i->device == dev->device ||
+ i->device == (u16)PCI_ANY_ID))
+ return i->dma_source(dev);
+ }
+
+ return pci_dev_get(dev);
+}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index d8c379dba6ad..39983be7b25b 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1332,6 +1332,9 @@ static inline struct pci_dev *pci_get_bus_and_slot(unsigned int bus,
static inline int pci_domain_nr(struct pci_bus *bus)
{ return 0; }
+static inline struct pci_dev *pci_dev_get(struct pci_dev *dev)
+{ return NULL; }
+
#define dev_is_pci(d) (false)
#define dev_is_pf(d) (false)
#define dev_num_vf(d) (0)
@@ -1486,9 +1489,14 @@ enum pci_fixup_pass {
#ifdef CONFIG_PCI_QUIRKS
void pci_fixup_device(enum pci_fixup_pass pass, struct pci_dev *dev);
+struct pci_dev *pci_get_dma_source(struct pci_dev *dev);
#else
static inline void pci_fixup_device(enum pci_fixup_pass pass,
struct pci_dev *dev) {}
+static inline struct pci_dev *pci_get_dma_source(struct pci_dev *dev)
+{
+ return pci_dev_get(dev);
+}
#endif
void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
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