From: Jacek Lawrynowicz <[email protected]>
<Insert changelog here>
---
drivers/iommu/iommu.c | 17 ++++++++++-------
drivers/pci/pci.c | 11 +++++++++--
drivers/pci/probe.c | 1 +
drivers/pci/search.c | 14 +++++++++-----
include/linux/pci.h | 4 +---
5 files changed, 30 insertions(+), 17 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 0e3b009..a214e19 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -659,9 +659,15 @@ static struct iommu_group
*get_pci_function_alias_group(struct pci_dev *pdev,
return NULL;
}
+static bool dma_alias_is_enabled(struct pci_dev *dev, u8 devfn)
+{
+ return dev->dma_alias_mask &&
+ test_bit(devfn, dev->dma_alias_mask);
+}
+
/*
- * Look for aliases to or from the given device for exisiting groups. The
- * dma_alias_devfn only supports aliases on the same bus, therefore the search
+ * Look for aliases to or from the given device for existing groups. DMA
+ * aliases are only supported on the same bus, therefore the search
* space is quite small (especially since we're really only looking at pcie
* device, and therefore only expect multiple slots on the root complex or
* downstream switch ports). It's conceivable though that a pair of
@@ -686,11 +692,8 @@ static struct iommu_group *get_pci_alias_group(struct
pci_dev *pdev,
continue;
/* We alias them or they alias us */
- if (((pdev->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN) &&
- pdev->dma_alias_devfn == tmp->devfn) ||
- ((tmp->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN) &&
- tmp->dma_alias_devfn == pdev->devfn)) {
-
+ if (dma_alias_is_enabled(pdev, tmp->devfn) ||
+ dma_alias_is_enabled(tmp, pdev->devfn)) {
group = get_pci_alias_group(tmp, devfns);
if (group) {
pci_dev_put(tmp);
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 8b0a637..eb4dd49 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4578,8 +4578,15 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode,
*/
void pci_add_dma_alias(struct pci_dev *dev, u8 devfn)
{
- dev->dma_alias_devfn = PCI_DEVFN(PCI_SLOT(dev->devfn), 0);
- dev->dev_flags |= PCI_DEV_FLAGS_DMA_ALIAS_DEVFN;
+ if (!dev->dma_alias_mask)
+ dev->dma_alias_mask = kcalloc(BITS_TO_LONGS(U8_MAX),
+ sizeof(long), GFP_KERNEL);
+ if (!dev->dma_alias_mask) {
+ dev_warn(&dev->dev, "Unable to allocate DMA alias mask\n");
+ return;
+ }
+
+ set_bit(devfn, dev->dma_alias_mask);
dev_info(&dev->dev, "Enabling fixed DMA alias to %02x.%d\n",
PCI_SLOT(devfn), PCI_FUNC(devfn));
}
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 6d7ab9b..23fc397 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1503,6 +1503,7 @@ static void pci_release_dev(struct device *dev)
pcibios_release_device(pci_dev);
pci_bus_put(pci_dev->bus);
kfree(pci_dev->driver_override);
+ kfree(pci_dev->dma_alias_mask);
kfree(pci_dev);
}
diff --git a/drivers/pci/search.c b/drivers/pci/search.c
index a20ce7d..33e0f03 100644
--- a/drivers/pci/search.c
+++ b/drivers/pci/search.c
@@ -40,11 +40,15 @@ int pci_for_each_dma_alias(struct pci_dev *pdev,
* If the device is broken and uses an alias requester ID for
* DMA, iterate over that too.
*/
- if (unlikely(pdev->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN)) {
- ret = fn(pdev, PCI_DEVID(pdev->bus->number,
- pdev->dma_alias_devfn), data);
- if (ret)
- return ret;
+ if (unlikely(pdev->dma_alias_mask)) {
+ u8 devfn;
+
+ for_each_set_bit(devfn, pdev->dma_alias_mask, U8_MAX) {
+ ret = fn(pdev, PCI_DEVID(pdev->bus->number, devfn),
+ data);
+ if (ret)
+ return ret;
+ }
}
for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) {
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 27df4a6..d9e0c84 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -172,8 +172,6 @@ enum pci_dev_flags {
PCI_DEV_FLAGS_ASSIGNED = (__force pci_dev_flags_t) (1 << 2),
/* Flag for quirk use to store if quirk-specific ACS is enabled */
PCI_DEV_FLAGS_ACS_ENABLED_QUIRK = (__force pci_dev_flags_t) (1 << 3),
- /* Flag to indicate the device uses dma_alias_devfn */
- PCI_DEV_FLAGS_DMA_ALIAS_DEVFN = (__force pci_dev_flags_t) (1 << 4),
/* Use a PCIe-to-PCI bridge alias even if !pci_is_pcie */
PCI_DEV_FLAG_PCIE_BRIDGE_ALIAS = (__force pci_dev_flags_t) (1 << 5),
/* Do not use bus resets for device */
@@ -279,7 +277,7 @@ struct pci_dev {
u8 rom_base_reg; /* which config register controls the
ROM */
u8 pin; /* which interrupt pin this device uses
*/
u16 pcie_flags_reg; /* cached PCIe Capabilities Register */
- u8 dma_alias_devfn;/* devfn of DMA alias, if any */
+ unsigned long *dma_alias_mask;/* mask of enabled devfn aliases */
struct pci_driver *driver; /* which driver has allocated this
device */
u64 dma_mask; /* Mask of the bits of bus address this
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