PCI drivers that support multiple MSI or MSI-X vectors currently have a lot of boileplate code to generate names for each vector (or simply use the same name for all of them, which isn't nice either). This series adds new helpers that allocate and free a name based on a format string passed to the request_irq wrapper. They also hide the [pci_dev,vector] to Linux irq number translation, in fact the example NVMe driver conversion now never sees the Linux irq number. That might be useful to isolate PCI drivers from our IRQ numbers, although to have a full abstraction we'd need similar wrappers for {enable,disable,synchronize}_irq as well.