From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: [PATCH 02/13] PCI: quirk pci_for_each_dma_alias() Date: Thu, 01 May 2014 10:27:18 -0600 Message-ID: <20140501162717.17512.25998.stgit@bling.home> References: <20140501160128.17512.23609.stgit@bling.home> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140501160128.17512.23609.stgit-xdHQ/5r00wBBDLzU/O5InQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Cc: bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: iommu@lists.linux-foundation.org There are a few broken devices that use the requester ID of a different function in the slot for their DMA. To handle these, add a bitmap to struct pci_dev (using an alignment gap) that quirks can populate. As we iterate over the device and bus DMA aliases, also iterate over any bits in the map. Signed-off-by: Alex Williamson --- drivers/pci/search.c | 21 +++++++++++++++++++++ include/linux/pci.h | 2 ++ 2 files changed, 23 insertions(+) diff --git a/drivers/pci/search.c b/drivers/pci/search.c index 5601cdb..ad698b2 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -37,6 +37,27 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, if (ret) return ret; + /* + * dma_func_alias provides a bitmap of other function numbers on + * this same PCI slot to use as DMA aliases. + */ + if (unlikely(pdev->dma_func_alias)) { + u8 map = pdev->dma_func_alias & ~(1 << PCI_FUNC(pdev->devfn)); + int func; + + for (func = 0; map && func < 8; func++, map >>= 1) { + if (!(map & 1)) + continue; + + ret = fn(pdev, + PCI_DEVID(pdev->bus->number, + PCI_DEVFN(PCI_SLOT(pdev->devfn), + func)), data); + if (ret) + return ret; + } + } + for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) { struct pci_dev *tmp; diff --git a/include/linux/pci.h b/include/linux/pci.h index 14b074b..b4c97d2 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -268,6 +268,8 @@ 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_func_alias; /* bitmap of functions used as DMA + aliases for this device */ struct pci_driver *driver; /* which driver has allocated this device */ u64 dma_mask; /* Mask of the bits of bus address this