On 27.04.20 17:17, Halil Pasic wrote: > On Mon, 27 Apr 2020 15:05:23 +0200 > Harald Freudenberger <freude@xxxxxxxxxxxxx> wrote: > >> On 24.04.20 05:57, Halil Pasic wrote: >>> On Tue, 7 Apr 2020 15:20:01 -0400 >>> Tony Krowiak <akrowiak@xxxxxxxxxxxxx> wrote: >>> >>>> Rather than looping over potentially 65535 objects, let's store the >>>> structures for caching information about queue devices bound to the >>>> vfio_ap device driver in a hash table keyed by APQN. >>> @Harald: >>> Would it make sense to make the efficient lookup of an apqueue base >>> on its APQN core AP functionality instead of each driver figuring it out >>> on it's own? >>> >>> If I'm not wrong the zcrypt device/driver(s) must the problem of >>> looking up a queue based on its APQN as well. >>> >>> For instance struct ep11_cprb has a target_id filed >>> (arch/s390/include/uapi/asm/zcrypt.h). >>> >>> Regards, >>> Halil >> Hi Halil >> >> no, the zcrypt drivers don't have this problem. They build up their own device object which >> includes a pointer to the base ap device. > I'm a bit confused. Doesn't your code loop first trough the ap_card > objects to find the APID portion of the APQN, and then loop the queue > list of the matching card to find the right ap_queue object? Or did I > miss something? Isn't that what _zcrypt_send_ep11_cprb() does? Can you > point me to the code that avoids the lookup (by apqn) for zcrypt? No. The code is looping through zcrypt_card and zcrypt_queue objects which are build up and held by the zcrypt api and the zcrypt driver(s). It does not deal with ap_card and ap_queue devices. > > > If you look at the new function of vfio_ap_get_queue(unsigned long apqn) > it basically about finding the queue based on the apqn, with the > difference that it is vfio specific. > > Regards, > Halil > >> However, this is not a big issue, as the ap_bus holds a list of ap_card objects and within each >> ap_card object there exists a list of ap_queues. > > >
