diff options
Diffstat (limited to 'drivers/pci/msi/api.c')
-rw-r--r-- | drivers/pci/msi/api.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c index 1714905943fb..8546749afa6e 100644 --- a/drivers/pci/msi/api.c +++ b/drivers/pci/msi/api.c @@ -123,3 +123,62 @@ int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs, flags, NULL); } EXPORT_SYMBOL(pci_alloc_irq_vectors); + +/** + * pci_alloc_irq_vectors_affinity() - Allocate multiple device interrupt + * vectors with affinity requirements + * @dev: the PCI device to operate on + * @min_vecs: minimum required number of vectors (must be >= 1) + * @max_vecs: maximum desired number of vectors + * @flags: allocation flags, as in pci_alloc_irq_vectors() + * @affd: affinity requirements (can be %NULL). + * + * Same as pci_alloc_irq_vectors(), but with the extra @affd parameter. + * Check that function docs, and &struct irq_affinity, for more details. + */ +int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs, + unsigned int max_vecs, unsigned int flags, + struct irq_affinity *affd) +{ + struct irq_affinity msi_default_affd = {0}; + int nvecs = -ENOSPC; + + if (flags & PCI_IRQ_AFFINITY) { + if (!affd) + affd = &msi_default_affd; + } else { + if (WARN_ON(affd)) + affd = NULL; + } + + if (flags & PCI_IRQ_MSIX) { + nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs, + affd, flags); + if (nvecs > 0) + return nvecs; + } + + if (flags & PCI_IRQ_MSI) { + nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd); + if (nvecs > 0) + return nvecs; + } + + /* use legacy IRQ if allowed */ + if (flags & PCI_IRQ_LEGACY) { + if (min_vecs == 1 && dev->irq) { + /* + * Invoke the affinity spreading logic to ensure that + * the device driver can adjust queue configuration + * for the single interrupt case. + */ + if (affd) + irq_create_affinity_masks(1, affd); + pci_intx(dev, 1); + return 1; + } + } + + return nvecs; +} +EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity); |