PCI/msi: fix the pci_alloc_irq_vectors_affinity stub

[ Upstream commit 83b4605b0c16cde5b00c8cf192408d51eab75402 ]

We need to return an error for any call that asks for MSI / MSI-X
vectors only, so that non-trivial fallback logic can work properly.

Also valid dev->irq and use the "correct" errno value based on feedback
from Linus.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: aff17164 ("PCI: Provide sensible IRQ vector alloc/free routines")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 1b71179..3652290 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1348,9 +1348,9 @@ static inline int pci_alloc_irq_vectors(struct pci_dev *dev,
                unsigned int min_vecs, unsigned int max_vecs,
                unsigned int flags)
 {
-       if (min_vecs > 1)
-               return -EINVAL;
-       return 1;
+       if ((flags & PCI_IRQ_LEGACY) && min_vecs == 1 && dev->irq)
+               return 1;
+       return -ENOSPC;
 }
 static inline void pci_free_irq_vectors(struct pci_dev *dev)
 {