diff --git a/drivers/s390/cio/device_pgid.c b/drivers/s390/cio/device_pgid.c index 32610fd8868e..1693a102dcfe 100644 --- a/drivers/s390/cio/device_pgid.c +++ b/drivers/s390/cio/device_pgid.c @@ -23,6 +23,21 @@ #include "device.h" #include "ioasm.h" +/* + * Helper function called from interrupt context to decide whether an + * operation should be tried again. + */ +static int __ccw_device_should_retry(struct scsw *scsw) +{ + /* CC is only valid if start function bit is set. */ + if ((scsw->fctl & SCSW_FCTL_START_FUNC) && scsw->cc == 1) + return 1; + /* No more activity. For sense and set PGID we stubbornly try again. */ + if (!scsw->actl) + return 1; + return 0; +} + /* * Start Sense Path Group ID helper function. Used in ccw_device_recog * and ccw_device_sense_pgid. @@ -155,10 +170,10 @@ ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event) int ret; irb = (struct irb *) __LC_IRB; - /* Retry sense pgid for cc=1. */ + if (irb->scsw.stctl == (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { - if (irb->scsw.cc == 1) { + if (__ccw_device_should_retry(&irb->scsw)) { ret = __ccw_device_sense_pgid_start(cdev); if (ret && ret != -EBUSY) ccw_device_sense_pgid_done(cdev, ret); @@ -391,10 +406,10 @@ ccw_device_verify_irq(struct ccw_device *cdev, enum dev_event dev_event) int ret; irb = (struct irb *) __LC_IRB; - /* Retry set pgid for cc=1. */ + if (irb->scsw.stctl == (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { - if (irb->scsw.cc == 1) + if (__ccw_device_should_retry(&irb->scsw)) __ccw_device_verify_start(cdev); return; } @@ -494,10 +509,10 @@ ccw_device_disband_irq(struct ccw_device *cdev, enum dev_event dev_event) int ret; irb = (struct irb *) __LC_IRB; - /* Retry set pgid for cc=1. */ + if (irb->scsw.stctl == (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { - if (irb->scsw.cc == 1) + if (__ccw_device_should_retry(&irb->scsw)) __ccw_device_disband_start(cdev); return; }