[PATCH 13/23] AMD IOMMU: add dma_supported callback

From: Joerg Roedel
Date: Wed Sep 17 2008 - 12:58:51 EST


This function determines if the AMD IOMMU implementation is responsible
for a given device. So the DMA layer can get this information from the
driver.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
arch/x86/kernel/amd_iommu.c | 25 +++++++++++++++++++++++++
1 files changed, 25 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 71e20ad..0410be1 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -1205,6 +1205,30 @@ free_mem:
}

/*
+ * This function is called by the DMA layer to find out if we can handle a
+ * particular device. It is part of the dma_ops.
+ */
+static int amd_iommu_dma_supported(struct device *dev, u64 mask)
+{
+ u16 bdf;
+ struct pci_dev *pcidev;
+
+ /* No device or no PCI device */
+ if (!dev || dev->bus != &pci_bus_type)
+ return 0;
+
+ pcidev = to_pci_dev(dev);
+
+ bdf = calc_devid(pcidev->bus->number, pcidev->devfn);
+
+ /* Out of our scope? */
+ if (bdf > amd_iommu_last_bdf)
+ return 0;
+
+ return 1;
+}
+
+/*
* The function for pre-allocating protection domains.
*
* If the driver core informs the DMA layer if a driver grabs a device
@@ -1247,6 +1271,7 @@ static struct dma_mapping_ops amd_iommu_dma_ops = {
.unmap_single = unmap_single,
.map_sg = map_sg,
.unmap_sg = unmap_sg,
+ .dma_supported = amd_iommu_dma_supported,
};

/*
--
1.5.6.4


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/