From 3f2a230caf21a1f7ac75f9e4892d0e5af9ccee88 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Tue, 11 Jan 2011 17:20:13 +0000 Subject: [PATCH] xen: handled remapped IRQs when enabling a pcifront PCI device. This happens to not be an issue currently because we take pains to try to ensure that the GSI-IRQ mapping is 1-1 in a PV guest and that regular event channels do not clash. However a subsequent patch is going to break this 1-1 mapping. Signed-off-by: Ian Campbell Signed-off-by: Konrad Rzeszutek Wilk Cc: Stefano Stabellini Cc: Jeremy Fitzhardinge --- arch/x86/pci/xen.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c index 25cd4a07d09f..2a12f3dbdd02 100644 --- a/arch/x86/pci/xen.c +++ b/arch/x86/pci/xen.c @@ -226,21 +226,27 @@ static int xen_pcifront_enable_irq(struct pci_dev *dev) { int rc; int share = 1; + u8 gsi; - dev_info(&dev->dev, "Xen PCI enabling IRQ: %d\n", dev->irq); - - if (dev->irq < 0) - return -EINVAL; + rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi); + if (rc < 0) { + dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n", + rc); + return rc; + } - if (dev->irq < NR_IRQS_LEGACY) + if (gsi < NR_IRQS_LEGACY) share = 0; - rc = xen_allocate_pirq(dev->irq, share, "pcifront"); + rc = xen_allocate_pirq(gsi, share, "pcifront"); if (rc < 0) { - dev_warn(&dev->dev, "Xen PCI IRQ: %d, failed to register:%d\n", - dev->irq, rc); + dev_warn(&dev->dev, "Xen PCI: failed to register GSI%d: %d\n", + gsi, rc); return rc; } + + dev->irq = rc; + dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi, dev->irq); return 0; } -- 2.11.0