On 2012-05-21 14:34, Michael S. Tsirkin wrote: > On Mon, May 21, 2012 at 10:13:47AM -0300, Jan Kiszka wrote: >> Add a PCI IRQ path discovery function that walks from a given device to >> the host bridge, returning the IRQ number that is reported to the >> attached interrupt controller. For this purpose, another PCI bridge >> callback function is introduced: map_host_irq. It is so far only >> implemented by the PIIX3, other host bridges can be added later on as >> required. >> >> Will be used for KVM PCI device assignment. >> >> Signed-off-by: Jan Kiszka <jan.kis...@siemens.com> > > interrupt injection is data path even for emulated devices. > So instead of special casing device assignment I would like to see all > devices converted to an API that caches irqs. > > This will likely mean that we can maintain the final > irq as part of the pci device structure, and > this api will simply return it.
Yep, I definitely agree. It's just that such a design has to please even more users than PCI devices, thus will likely take longer to settle than the device assignment effort. Therefore I decided to rush forward with an intermediate approach first. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux