[PATCHv4,4/6] x86-pci: allow pci domain specific dma ops

Commit Message

Keith Busch Nov. 6, 2015, 10:35 p.m. UTC

New x86 pci h/w will require DMA operations specific to that domain. This
patch allows those domains to register their operations, and sets devices
as they are discovered in that domain to use them.

Signed-off-by: Keith Busch <[e-mail]>
---
 arch/x86/include/asm/device.h | 10 ++++++++++
 arch/x86/pci/common.c         | 38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+)

Patch

diff --git a/arch/x86/include/asm/device.h b/arch/x86/include/asm/device.h
index 03dd729..3b23897 100644
--- a/arch/x86/include/asm/device.h
+++ b/arch/x86/include/asm/device.h
@@ -10,6 +10,16 @@  struct dev_archdata {
 #endif
 };
 
+#if defined(CONFIG_X86_DEV_DMA_OPS) && defined(CONFIG_PCI_DOMAINS)
+struct dma_domain {
+	struct list_head node;
+	struct dma_map_ops *dma_ops;
+	int domain_nr;
+};
+extern void add_dma_domain(struct dma_domain *domain);
+extern void del_dma_domain(struct dma_domain *domain);
+#endif
+
 struct pdev_archdata {
 };
 
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index dc78a4a..e227ba2 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -641,6 +641,43 @@  unsigned int pcibios_assign_all_busses(void)
 	return (pci_probe & PCI_ASSIGN_ALL_BUSSES) ? 1 : 0;
 }
 
+#if defined(CONFIG_X86_DEV_DMA_OPS) && defined(CONFIG_PCI_DOMAINS)
+LIST_HEAD(dma_domain_list);
+DEFINE_SPINLOCK(dma_domain_list_lock);
+
+void add_dma_domain(struct dma_domain *domain)
+{
+	spin_lock(&dma_domain_list_lock);
+	list_add(&domain->node, &dma_domain_list);
+	spin_unlock(&dma_domain_list_lock);
+}
+EXPORT_SYMBOL_GPL(add_dma_domain);
+
+void del_dma_domain(struct dma_domain *domain)
+{
+	spin_lock(&dma_domain_list_lock);
+	list_del(&domain->node);
+	spin_unlock(&dma_domain_list_lock);
+}
+EXPORT_SYMBOL_GPL(del_dma_domain);
+
+static void set_dma_domain_ops(struct pci_dev *pdev)
+{
+	struct dma_domain *domain;
+
+	spin_lock(&dma_domain_list_lock);
+	list_for_each_entry(domain, &dma_domain_list, node) {
+		if (pci_domain_nr(pdev->bus) == domain->domain_nr) {
+			pdev->dev.archdata.dma_ops = domain->dma_ops;
+			break;
+		}
+	}
+	spin_unlock(&dma_domain_list_lock);
+}
+#else
+static void set_dma_domain_ops(struct pci_dev *pdev) {}
+#endif
+
 int pcibios_add_device(struct pci_dev *dev)
 {
 	struct setup_data *data;
@@ -670,6 +707,7 @@  int pcibios_add_device(struct pci_dev *dev)
 		pa_data = data->next;
 		iounmap(data);
 	}
+	set_dma_domain_ops(dev);
 	return 0;
 }