If an asynchronous event callback has been set up then the callback function should be defined.
static void ahc_async(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
callback_arg - the value supplied when registering the callback
code - identifies the type of event
path - identifies the devices to which the event applies
arg - event-specific argument
Implementation for a single type of event, AC_LOST_DEVICE, looks like:
struct xxx_softc *softc;
struct cam_sim *sim;
int targ;
struct ccb_trans_settings neg;
sim = (struct cam_sim *)callback_arg;
softc = (struct xxx_softc *)cam_sim_softc(sim);
switch (code) {
case AC_LOST_DEVICE:
targ = xpt_path_target_id(path);
if(targ <= OUR_MAX_SUPPORTED_TARGET) {
clean_negotiations(softc, targ);
/* send indication to CAM */
neg.bus_width = 8;
neg.sync_period = neg.sync_offset = 0;
neg.valid = (CCB_TRANS_BUS_WIDTH_VALID
| CCB_TRANS_SYNC_RATE_VALID | CCB_TRANS_SYNC_OFFSET_VALID);
xpt_async(AC_TRANSFER_NEG, path, &neg);
}
break;
default:
break;
}All FreeBSD documents are available for download at https://download.freebsd.org/ftp/doc/
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