[PATCH 5.4 135/344] PCI: Add nr_devfns parameter to pci_add_dma_alias()

Greg Kroah-Hartman
2020-02-21T08:35:49Z

From: James Sewart <jamessewart@arista.com>

[ Upstream commit 09298542cd891b43778db1f65aa3613aa5a562eb ]

Add a "nr_devfns" parameter to pci_add_dma_alias() so it can be used to
create DMA aliases for a range of devfns.

[bhelgaas: incorporate nr_devfns fix from James, update
quirk_pex_vca_alias() and setup_aliases()]
Signed-off-by: James Sewart <jamessewart@arista.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/amd_iommu.c | 7 ++-----
drivers/pci/pci.c | 22 +++++++++++++++++-----
drivers/pci/quirks.c | 23 +++++++++--------------
include/linux/pci.h | 2 +-
4 files changed, 29 insertions(+), 25 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 454695b372c8c..8bd5d608a82c2 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -272,11 +272,8 @@ static struct pci_dev *setup_aliases(struct device *dev)
*/
ivrs_alias = amd_iommu_alias_table[pci_dev_id(pdev)];
if (ivrs_alias != pci_dev_id(pdev) &&
- PCI_BUS_NUM(ivrs_alias) == pdev->bus->number) {
- pci_add_dma_alias(pdev, ivrs_alias & 0xff);
- pci_info(pdev, "Added PCI DMA alias %02x.%d\n",
- PCI_SLOT(ivrs_alias), PCI_FUNC(ivrs_alias));
- }
+ PCI_BUS_NUM(ivrs_alias) == pdev->bus->number)
+ pci_add_dma_alias(pdev, ivrs_alias & 0xff, 1);

clone_aliases(pdev);

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index cbf3d3889874c..981ae16f935bc 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5875,7 +5875,8 @@ EXPORT_SYMBOL_GPL(pci_pr3_present);
/**
* pci_add_dma_alias - Add a DMA devfn alias for a device
* @dev: the PCI device for which alias is added
- * @devfn: alias slot and function
+ * @devfn_from: alias slot and function
+ * @nr_devfns: number of subsequent devfns to alias
*
* This helper encodes an 8-bit devfn as a bit number in dma_alias_mask
* which is used to program permissible bus-devfn source addresses for DMA
@@ -5891,8 +5892,13 @@ EXPORT_SYMBOL_GPL(pci_pr3_present);
* cannot be left as a userspace activity). DMA aliases should therefore
* be configured via quirks, such as the PCI fixup header quirk.
*/
-void pci_add_dma_alias(struct pci_dev *dev, u8 devfn)
+void pci_add_dma_alias(struct pci_dev *dev, u8 devfn_from, unsigned nr_devfns)
{
+ int devfn_to;
+
+ nr_devfns = min(nr_devfns, (unsigned) MAX_NR_DEVFNS - devfn_from);
+ devfn_to = devfn_from + nr_devfns - 1;
+
if (!dev->dma_alias_mask)
dev->dma_alias_mask = bitmap_zalloc(MAX_NR_DEVFNS, GFP_KERNEL);
if (!dev->dma_alias_mask) {
@@ -5900,9 +5906,15 @@ void pci_add_dma_alias(struct pci_dev *dev, u8 devfn)
return;
}

- set_bit(devfn, dev->dma_alias_mask);
- pci_info(dev, "Enabling fixed DMA alias to %02x.%d\n",
- PCI_SLOT(devfn), PCI_FUNC(devfn));
+ bitmap_set(dev->dma_alias_mask, devfn_from, nr_devfns);
+
+ if (nr_devfns == 1)
+ pci_info(dev, "Enabling fixed DMA alias to %02x.%d\n",
+ PCI_SLOT(devfn_from), PCI_FUNC(devfn_from));
+ else if (nr_devfns > 1)
+ pci_info(dev, "Enabling fixed DMA alias for devfn range from %02x.%d to %02x.%d\n",
+ PCI_SLOT(devfn_from), PCI_FUNC(devfn_from),
+ PCI_SLOT(devfn_to), PCI_FUNC(devfn_to));
}

bool pci_devs_are_dma_aliases(struct pci_dev *dev1, struct pci_dev *dev2)
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 7b6df2d8d6cde..67a9ad3734d18 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3927,7 +3927,7 @@ int pci_dev_specific_reset(struct pci_dev *dev, int probe)
static void quirk_dma_func0_alias(struct pci_dev *dev)
{
if (PCI_FUNC(dev->devfn) != 0)
- pci_add_dma_alias(dev, PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
+ pci_add_dma_alias(dev, PCI_DEVFN(PCI_SLOT(dev->devfn), 0), 1);
}

/*
@@ -3941,7 +3941,7 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_RICOH, 0xe476, quirk_dma_func0_alias);
static void quirk_dma_func1_alias(struct pci_dev *dev)
{
if (PCI_FUNC(dev->devfn) != 1)
- pci_add_dma_alias(dev, PCI_DEVFN(PCI_SLOT(dev->devfn), 1));
+ pci_add_dma_alias(dev, PCI_DEVFN(PCI_SLOT(dev->devfn), 1), 1);
}

/*
@@ -4026,7 +4026,7 @@ static void quirk_fixed_dma_alias(struct pci_dev *dev)

id = pci_match_id(fixed_dma_alias_tbl, dev);
if (id)
- pci_add_dma_alias(dev, id->driver_data);
+ pci_add_dma_alias(dev, id->driver_data, 1);
}

DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ADAPTEC2, 0x0285, quirk_fixed_dma_alias);
@@ -4068,9 +4068,9 @@ DECLARE_PCI_FIXUP_HEADER(0x8086, 0x244e, quirk_use_pcie_bridge_dma_alias);
*/
static void quirk_mic_x200_dma_alias(struct pci_dev *pdev)
{
- pci_add_dma_alias(pdev, PCI_DEVFN(0x10, 0x0));
- pci_add_dma_alias(pdev, PCI_DEVFN(0x11, 0x0));
- pci_add_dma_alias(pdev, PCI_DEVFN(0x12, 0x3));
+ pci_add_dma_alias(pdev, PCI_DEVFN(0x10, 0x0), 1);
+ pci_add_dma_alias(pdev, PCI_DEVFN(0x11, 0x0), 1);
+ pci_add_dma_alias(pdev, PCI_DEVFN(0x12, 0x3), 1);
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2260, quirk_mic_x200_dma_alias);
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2264, quirk_mic_x200_dma_alias);
@@ -4094,13 +4094,8 @@ static void quirk_pex_vca_alias(struct pci_dev *pdev)
const unsigned int num_pci_slots = 0x20;
unsigned int slot;

- for (slot = 0; slot < num_pci_slots; slot++) {
- pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x0));
- pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x1));
- pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x2));
- pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x3));
- pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x4));
- }
+ for (slot = 0; slot < num_pci_slots; slot++)
+ pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x0), 5);
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2954, quirk_pex_vca_alias);
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2955, quirk_pex_vca_alias);
@@ -5315,7 +5310,7 @@ static void quirk_switchtec_ntb_dma_alias(struct pci_dev *pdev)
pci_dbg(pdev,
"Aliasing Partition %d Proxy ID %02x.%d\n",
pp, PCI_SLOT(devfn), PCI_FUNC(devfn));
- pci_add_dma_alias(pdev, devfn);
+ pci_add_dma_alias(pdev, devfn, 1);
}
}

diff --git a/include/linux/pci.h b/include/linux/pci.h
index be529d311122d..f39f22f9ee474 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2324,7 +2324,7 @@ static inline struct eeh_dev *pci_dev_to_eeh_dev(struct pci_dev *pdev)
}
#endif

-void pci_add_dma_alias(struct pci_dev *dev, u8 devfn);
+void pci_add_dma_alias(struct pci_dev *dev, u8 devfn_from, unsigned nr_devfns);
bool pci_devs_are_dma_aliases(struct pci_dev *dev1, struct pci_dev *dev2);
int pci_for_each_dma_alias(struct pci_dev *pdev,
int (*fn)(struct pci_dev *pdev,
--
2.20.1