PCI: add an API to get node from vector

Next patch will use the API to get the node from vector for nvme device

Signed-off-by: Shaohua Li <shli@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 980eaf588281808a8e8e0431b717ec6120d05cf8..d571bc330686517a389efec290d0cf499fb0dbd5 100644 (file)
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -1298,6 +1298,22 @@ const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
 }
 EXPORT_SYMBOL(pci_irq_get_affinity);
 
+/**
+ * pci_irq_get_node - return the numa node of a particular msi vector
+ * @pdev:      PCI device to operate on
+ * @vec:       device-relative interrupt vector index (0-based).
+ */
+int pci_irq_get_node(struct pci_dev *pdev, int vec)
+{
+       const struct cpumask *mask;
+
+       mask = pci_irq_get_affinity(pdev, vec);
+       if (mask)
+               return local_memory_node(cpu_to_node(cpumask_first(mask)));
+       return dev_to_node(&pdev->dev);
+}
+EXPORT_SYMBOL(pci_irq_get_node);
+
 struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc)
 {
        return to_pci_dev(desc->dev);

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 282ed32244ce793ae3f97a13dd7bc0e521d4a926..eb3da1a04e6cdc7d3f4efab5532f53abcdf3a28f 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1323,6 +1323,7 @@ int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
 void pci_free_irq_vectors(struct pci_dev *dev);
 int pci_irq_vector(struct pci_dev *dev, unsigned int nr);
 const struct cpumask *pci_irq_get_affinity(struct pci_dev *pdev, int vec);
+int pci_irq_get_node(struct pci_dev *pdev, int vec);
 
 #else
 static inline int pci_msi_vec_count(struct pci_dev *dev) { return -ENOSYS; }
@@ -1370,6 +1371,11 @@ static inline const struct cpumask *pci_irq_get_affinity(struct pci_dev *pdev,
 {
        return cpu_possible_mask;
 }
+
+static inline int pci_irq_get_node(struct pci_dev *pdev, int vec)
+{
+       return first_online_node;
+}
 #endif
 
 static inline int