@@ -126,6 +126,11 @@ enum uc_todo {
* @notify: notify driver of device state changes
* @path_event: notify driver of channel path events
* @shutdown: called at device shutdown
+ * @prepare: prepare for pm state transition
+ * @complete: undo work done in @prepare
+ * @freeze: callback for freezing during hibernation snapshotting
+ * @thaw: undo work done in @freeze
+ * @restore: callback for restoring after hibernation
* @uc_handler: callback for unit check handler
* @driver: embedded device driver structure
* @int_class: interruption class to use for accounting interrupts
@@ -139,6 +144,11 @@ struct ccw_driver {
int (*notify) (struct ccw_device *, int);
void (*path_event) (struct ccw_device *, int *);
void (*shutdown) (struct ccw_device *);
+ int (*prepare) (struct ccw_device *);
+ void (*complete) (struct ccw_device *);
+ int (*freeze)(struct ccw_device *);
+ int (*thaw) (struct ccw_device *);
+ int (*restore)(struct ccw_device *);
enum uc_todo (*uc_handler) (struct ccw_device *, struct irb *);
struct device_driver driver;
enum interruption_class int_class;
@@ -1109,6 +1109,11 @@ static ssize_t cmb_enable_store(struct device *dev,
}
DEVICE_ATTR_RW(cmb_enable);
+int ccw_set_cmf(struct ccw_device *cdev, int enable)
+{
+ return cmbops->set(cdev, enable ? 2 : 0);
+}
+
/**
* enable_cmf() - switch on the channel measurement for a specific device
* @cdev: The ccw device to be enabled
@@ -1421,7 +1421,7 @@ static enum io_sch_action sch_get_action(struct subchannel *sch)
}
if (device_is_disconnected(cdev))
return IO_SCH_REPROBE;
- if (cdev->online)
+ if (cdev->online && !cdev->private->flags.resuming)
return IO_SCH_VERIFY;
if (cdev->private->state == DEV_STATE_NOT_OPER)
return IO_SCH_UNREG_ATTACH;
@@ -1513,6 +1513,11 @@ static int io_subchannel_sch_event(struct subchannel *sch, int process)
break;
case IO_SCH_UNREG_ATTACH:
spin_lock_irqsave(sch->lock, flags);
+ if (cdev->private->flags.resuming) {
+ /* Device will be handled later. */
+ rc = 0;
+ goto out_unlock;
+ }
sch_set_cdev(sch, NULL);
spin_unlock_irqrestore(sch->lock, flags);
/* Unregister ccw device. */
@@ -1525,7 +1530,7 @@ static int io_subchannel_sch_event(struct subchannel *sch, int process)
switch (action) {
case IO_SCH_ORPH_UNREG:
case IO_SCH_UNREG:
- if (!cdev)
+ if (!cdev || !cdev->private->flags.resuming)
css_sch_device_unregister(sch);
break;
case IO_SCH_ORPH_ATTACH:
@@ -1684,6 +1689,14 @@ void ccw_device_wait_idle(struct ccw_device *cdev)
udelay(100);
}
}
+
+static int ccw_device_pm_restore(struct device *dev);
+
+int ccw_device_force_console(struct ccw_device *cdev)
+{
+ return ccw_device_pm_restore(&cdev->dev);
+}
+EXPORT_SYMBOL_GPL(ccw_device_force_console);
#endif
/**
@@ -1784,6 +1797,235 @@ static void ccw_device_shutdown(struct device *dev)
__disable_cmf(cdev);
}
+static int ccw_device_pm_prepare(struct device *dev)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+
+ if (work_pending(&cdev->private->todo_work))
+ return -EAGAIN;
+ /* Fail while device is being set online/offline. */
+ if (atomic_read(&cdev->private->onoff))
+ return -EAGAIN;
+
+ if (cdev->online && cdev->drv && cdev->drv->prepare)
+ return cdev->drv->prepare(cdev);
+
+ return 0;
+}
+
+static void ccw_device_pm_complete(struct device *dev)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+
+ if (cdev->online && cdev->drv && cdev->drv->complete)
+ cdev->drv->complete(cdev);
+}
+
+static int ccw_device_pm_freeze(struct device *dev)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+ int ret, cm_enabled;
+
+ /* Fail suspend while device is in transistional state. */
+ if (!dev_fsm_final_state(cdev))
+ return -EAGAIN;
+ if (!cdev->online)
+ return 0;
+ if (cdev->drv && cdev->drv->freeze) {
+ ret = cdev->drv->freeze(cdev);
+ if (ret)
+ return ret;
+ }
+
+ spin_lock_irq(sch->lock);
+ cm_enabled = cdev->private->cmb != NULL;
+ spin_unlock_irq(sch->lock);
+ if (cm_enabled) {
+ /* Don't have the css write on memory. */
+ ret = ccw_set_cmf(cdev, 0);
+ if (ret)
+ return ret;
+ }
+ /* From here on, disallow device driver I/O. */
+ spin_lock_irq(sch->lock);
+ ret = cio_disable_subchannel(sch);
+ spin_unlock_irq(sch->lock);
+
+ return ret;
+}
+
+static int ccw_device_pm_thaw(struct device *dev)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+ int ret, cm_enabled;
+
+ if (!cdev->online)
+ return 0;
+
+ spin_lock_irq(sch->lock);
+ /* Allow device driver I/O again. */
+ ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
+ cm_enabled = cdev->private->cmb != NULL;
+ spin_unlock_irq(sch->lock);
+ if (ret)
+ return ret;
+
+ if (cm_enabled) {
+ ret = ccw_set_cmf(cdev, 1);
+ if (ret)
+ return ret;
+ }
+
+ if (cdev->drv && cdev->drv->thaw)
+ ret = cdev->drv->thaw(cdev);
+
+ return ret;
+}
+
+static void __ccw_device_pm_restore(struct ccw_device *cdev)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+ spin_lock_irq(sch->lock);
+ if (cio_is_console(sch->schid)) {
+ cio_enable_subchannel(sch, (u32)(addr_t)sch);
+ goto out_unlock;
+ }
+ /*
+ * While we were sleeping, devices may have gone or become
+ * available again. Kick re-detection.
+ */
+ cdev->private->flags.resuming = 1;
+ cdev->private->path_new_mask = LPM_ANYPATH;
+ css_sched_sch_todo(sch, SCH_TODO_EVAL);
+ spin_unlock_irq(sch->lock);
+ css_wait_for_slow_path();
+
+ /* cdev may have been moved to a different subchannel. */
+ sch = to_subchannel(cdev->dev.parent);
+ spin_lock_irq(sch->lock);
+ if (cdev->private->state != DEV_STATE_ONLINE &&
+ cdev->private->state != DEV_STATE_OFFLINE)
+ goto out_unlock;
+
+ ccw_device_recognition(cdev);
+ spin_unlock_irq(sch->lock);
+ wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
+ cdev->private->state == DEV_STATE_DISCONNECTED);
+ spin_lock_irq(sch->lock);
+
+out_unlock:
+ cdev->private->flags.resuming = 0;
+ spin_unlock_irq(sch->lock);
+}
+
+static int resume_handle_boxed(struct ccw_device *cdev)
+{
+ cdev->private->state = DEV_STATE_BOXED;
+ if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
+ return 0;
+ ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
+ return -ENODEV;
+}
+
+static int resume_handle_disc(struct ccw_device *cdev)
+{
+ cdev->private->state = DEV_STATE_DISCONNECTED;
+ if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
+ return 0;
+ ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
+ return -ENODEV;
+}
+
+static int ccw_device_pm_restore(struct device *dev)
+{
+ struct ccw_device *cdev = to_ccwdev(dev);
+ struct subchannel *sch;
+ int ret = 0;
+
+ __ccw_device_pm_restore(cdev);
+ sch = to_subchannel(cdev->dev.parent);
+ spin_lock_irq(sch->lock);
+ if (cio_is_console(sch->schid))
+ goto out_restore;
+
+ /* check recognition results */
+ switch (cdev->private->state) {
+ case DEV_STATE_OFFLINE:
+ case DEV_STATE_ONLINE:
+ cdev->private->flags.donotify = 0;
+ break;
+ case DEV_STATE_BOXED:
+ ret = resume_handle_boxed(cdev);
+ if (ret)
+ goto out_unlock;
+ goto out_restore;
+ default:
+ ret = resume_handle_disc(cdev);
+ if (ret)
+ goto out_unlock;
+ goto out_restore;
+ }
+ /* check if the device type has changed */
+ if (!ccw_device_test_sense_data(cdev)) {
+ ccw_device_update_sense_data(cdev);
+ ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
+ ret = -ENODEV;
+ goto out_unlock;
+ }
+ if (!cdev->online)
+ goto out_unlock;
+
+ if (ccw_device_online(cdev)) {
+ ret = resume_handle_disc(cdev);
+ if (ret)
+ goto out_unlock;
+ goto out_restore;
+ }
+ spin_unlock_irq(sch->lock);
+ wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
+ spin_lock_irq(sch->lock);
+
+ if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
+ ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
+ ret = -ENODEV;
+ goto out_unlock;
+ }
+
+ /* reenable cmf, if needed */
+ if (cdev->private->cmb) {
+ spin_unlock_irq(sch->lock);
+ ret = ccw_set_cmf(cdev, 1);
+ spin_lock_irq(sch->lock);
+ if (ret) {
+ CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
+ "(rc=%d)\n", cdev->private->dev_id.ssid,
+ cdev->private->dev_id.devno, ret);
+ ret = 0;
+ }
+ }
+
+out_restore:
+ spin_unlock_irq(sch->lock);
+ if (cdev->online && cdev->drv && cdev->drv->restore)
+ ret = cdev->drv->restore(cdev);
+ return ret;
+
+out_unlock:
+ spin_unlock_irq(sch->lock);
+ return ret;
+}
+
+static const struct dev_pm_ops ccw_pm_ops = {
+ .prepare = ccw_device_pm_prepare,
+ .complete = ccw_device_pm_complete,
+ .freeze = ccw_device_pm_freeze,
+ .thaw = ccw_device_pm_thaw,
+ .restore = ccw_device_pm_restore,
+};
+
static struct bus_type ccw_bus_type = {
.name = "ccw",
.match = ccw_bus_match,
@@ -1791,6 +2033,7 @@ static struct bus_type ccw_bus_type = {
.probe = ccw_device_probe,
.remove = ccw_device_remove,
.shutdown = ccw_device_shutdown,
+ .pm = &ccw_pm_ops,
};
/**
@@ -143,5 +143,6 @@ void retry_set_schib(struct ccw_device *cdev);
void cmf_retry_copy_block(struct ccw_device *);
int cmf_reenable(struct ccw_device *);
void cmf_reactivate(void);
+int ccw_set_cmf(struct ccw_device *cdev, int enable);
extern struct device_attribute dev_attr_cmb_enable;
#endif
@@ -224,6 +224,12 @@ ccw_device_recog_done(struct ccw_device *cdev, int state)
wake_up(&cdev->private->wait_q);
return;
}
+ if (cdev->private->flags.resuming) {
+ cdev->private->state = state;
+ cdev->private->flags.recog_done = 1;
+ wake_up(&cdev->private->wait_q);
+ return;
+ }
switch (state) {
case DEV_STATE_NOT_OPER:
break;
@@ -160,6 +160,7 @@ struct ccw_device_private {
unsigned int donotify:1; /* call notify function */
unsigned int recog_done:1; /* dev. recog. complete */
unsigned int fake_irb:2; /* deliver faked irb */
+ unsigned int resuming:1; /* recognition while resume */
unsigned int pgroup:1; /* pathgroup is set up */
unsigned int mpath:1; /* multipathing is set up */
unsigned int pgid_unknown:1;/* unknown pgid state */
BugLink: https://bugs.launchpad.net/bugs/1925211 This reverts commit 8cc0dcfdc1c0e0be107d0288f9c0cf1f4201be62, which introduces a regression with hot-unplug of virtio disks from VMs. Roll back these changes until we have a proper fix. Signed-off-by: Seth Forshee <seth.forshee@canonical.com> --- arch/s390/include/asm/ccwdev.h | 10 ++ drivers/s390/cio/cmf.c | 5 + drivers/s390/cio/device.c | 247 ++++++++++++++++++++++++++++++++- drivers/s390/cio/device.h | 1 + drivers/s390/cio/device_fsm.c | 6 + drivers/s390/cio/io_sch.h | 1 + 6 files changed, 268 insertions(+), 2 deletions(-)