On 2019-11-29 5:49 a.m., James Sewart wrote:
> pci_add_dma_alias can now be used to create a dma alias for a range of
> devfns.
>
> Signed-off-by: James Sewart <jamessewart@xxxxxxxxxx>
> ---
> drivers/pci/pci.c | 23 ++++++++++++++++++-----
> drivers/pci/quirks.c | 14 +++++++-------
> include/linux/pci.h | 2 +-
> 3 files changed, 26 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index a97e2571a527..9b0e3481fe17 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5857,7 +5857,8 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode,
> /**
> * 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
> @@ -5873,8 +5874,14 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode,
> * 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;
> +
> + if (nr_devfns > U8_MAX+1)
> + nr_devfns = U8_MAX+1;
Why +1? That doesn't seem right to me....
> + devfn_to = devfn_from + nr_devfns - 1;
> +
> if (!dev->dma_alias_mask)
> dev->dma_alias_mask = bitmap_zalloc(U8_MAX, GFP_KERNEL);
> if (!dev->dma_alias_mask) {
> @@ -5882,9 +5889,15 @@ 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 320255e5e8f8..0f3f5afc73fd 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -3932,7 +3932,7 @@ 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);
> }
>
> /*
> @@ -3946,7 +3946,7 @@ 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);
> }
>
> /*
> @@ -4031,7 +4031,7 @@ 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);
> @@ -4073,9 +4073,9 @@ 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);
> @@ -5273,7 +5273,7 @@ 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 1a6cf19eac2d..84a8d4c2b24e 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -2323,7 +2323,7 @@ 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,
>
