diff options
Diffstat (limited to 'drivers/s390/cio/device.c')
| -rw-r--r-- | drivers/s390/cio/device.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c index 2b50f93b7fe..af500aac24e 100644 --- a/drivers/s390/cio/device.c +++ b/drivers/s390/cio/device.c @@ -892,12 +892,27 @@ static int ccw_device_move_to_sch(struct ccw_device *cdev, struct subchannel *sch) { struct subchannel *old_sch; - int rc; + int rc, old_enabled = 0; old_sch = to_subchannel(cdev->dev.parent); /* Obtain child reference for new parent. */ if (!get_device(&sch->dev)) return -ENODEV; + + if (!sch_is_pseudo_sch(old_sch)) { + spin_lock_irq(old_sch->lock); + old_enabled = old_sch->schib.pmcw.ena; + rc = 0; + if (old_enabled) + rc = cio_disable_subchannel(old_sch); + spin_unlock_irq(old_sch->lock); + if (rc == -EBUSY) { + /* Release child reference for new parent. */ + put_device(&sch->dev); + return rc; + } + } + mutex_lock(&sch->reg_mutex); rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV); mutex_unlock(&sch->reg_mutex); @@ -906,6 +921,12 @@ static int ccw_device_move_to_sch(struct ccw_device *cdev, cdev->private->dev_id.ssid, cdev->private->dev_id.devno, sch->schid.ssid, sch->schib.pmcw.dev, rc); + if (old_enabled) { + /* Try to reenable the old subchannel. */ + spin_lock_irq(old_sch->lock); + cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch); + spin_unlock_irq(old_sch->lock); + } /* Release child reference for new parent. */ put_device(&sch->dev); return rc; @@ -914,7 +935,6 @@ static int ccw_device_move_to_sch(struct ccw_device *cdev, if (!sch_is_pseudo_sch(old_sch)) { spin_lock_irq(old_sch->lock); sch_set_cdev(old_sch, NULL); - cio_disable_subchannel(old_sch); spin_unlock_irq(old_sch->lock); css_schedule_eval(old_sch->schid); } |