On 13/12/12 12:06, Alexander Graf wrote: > > On 12.12.2012, at 21:12, Christian Borntraeger wrote: > >> On 12/12/12 19:31, Alexander Graf wrote: >> +static inline long do_kvm_notify(struct subchannel_id schid, >>>> + unsigned long queue_index) >>>> +{ >>>> + register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY; >>>> + register struct subchannel_id __schid asm("2") = schid; >>> >>> How does the compiler know that the struct fits within a register? >>> >> >> Well it knows that sizeof struct subchannel_id is 4. > > How so? The asm/ccwdev.h header simply says > > struct subchannel_id; see original patch: >>> +#include <asm/cio.h> >>> +#include <asm/ccwdev.h> >>> +#include <asm/schid.h> >>> + >>> +/* >>> + * virtio related functions >>> + */ >>> + asm/schid.h includes uapi/asm/schid.h and that contains the definition. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html