[PATCH] PCI: Provide a boot parameter to disable MSI

Several drivers are starting to grow options to disable MSI.  However,
it's often a host chipset issue, not something which individual drivers
should handle.  So we add the pci=nomsi kernel parameter to allow the user
to disable MSI modes for systems we haven't added to the quirk list yet.

Signed-off-by: Matthew Wilcox <[email protected]>
Signed-off-by: Randy Dunlap <[email protected]>
Acked-by: Jeff Garzik <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index a6dfee2..8f3fb47 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -50,8 +50,10 @@
 
 #ifdef CONFIG_PCI_MSI
 void disable_msi_mode(struct pci_dev *dev, int pos, int type);
+void pci_no_msi(void);
 #else
 static inline void disable_msi_mode(struct pci_dev *dev, int pos, int type) { }
+static inline void pci_no_msi(void) { }
 #endif
 
 extern int pcie_mch_quirk;