How to display and update kernel parameters via SYSFS or proc

/* DEVICE_ATTR (state) clashes with Dev_attr_state for Sdev */struct device_attribute dev_attr_hstate =__ATTR (state, S_IRU GO | S_IWUSR, Show_shost_state, store_shost_state); static ssize_tshow_shost_mode (unsigned int mode, char *buf) {ssize_t len =  0;if (Mode & mode_initiator) len = sprintf (buf, "%s", "initiator"), if (Mode & mode_target) len + sprintf (buf + len, "%s%s", Len? ",": "", "Target"), Len + = sprintf (buf + len, "\ n"); return Len;

How to display and update kernel parameters via SYSFS or proc