Not all MSI domains support runtime expansions of PCI/MSI-X vectors. Add a domain flag so implementations can opt in. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> --- include/linux/msi.h | 2 ++ 1 file changed, 2 insertions(+) --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -494,6 +494,8 @@ enum { MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS = (1 << 9), /* Free MSI descriptors */ MSI_FLAG_FREE_MSI_DESCS = (1 << 10), + /* MSI vectors can be expanded after initial setup */ + MSI_FLAG_CAN_EXPAND = (1 << 11), }; int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask,