+/*
+ * Use tpi to get a pending interrupt, call the interrupt handler and
+ * return a pointer to the subchannel structure.
+ */
+static int cio_tpi(void)
+{
+ struct tpi_info *tpi_info;
+ struct subchannel *sch;
+ struct irb *irb;
+ int irq_context;
+
+ tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID;
+ if (tpi(NULL) != 1)
+ return 0;
+ irb = (struct irb *) __LC_IRB;
+ /* Store interrupt response block to lowcore. */
+ if (tsch(tpi_info->schid, irb) != 0)
+ /* Not status pending or not operational. */
+ return 1;
+ sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
+ if (!sch)
+ return 1;
+ irq_context = in_interrupt();
+ if (!irq_context)
+ local_bh_disable();
+ irq_enter();
+ spin_lock(sch->lock);
+ memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw));
+ if (sch->driver && sch->driver->irq)
+ sch->driver->irq(sch);
+ spin_unlock(sch->lock);
+ irq_exit();
+ if (!irq_context)
+ _local_bh_enable();
+ return 1;
+}
+