[ATA_LPM_MIN_POWER] = "min_power",
};
-static ssize_t ata_scsi_lpm_store(struct device *dev,
+static ssize_t ata_scsi_lpm_store(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
- struct Scsi_Host *shost = class_to_shost(dev);
+ struct Scsi_Host *shost = class_to_shost(device);
struct ata_port *ap = ata_shost_to_port(shost);
+ struct ata_link *link;
+ struct ata_device *dev;
enum ata_lpm_policy policy;
unsigned long flags;
return -EINVAL;
spin_lock_irqsave(ap->lock, flags);
+
+ ata_for_each_link(link, ap, EDGE) {
+ ata_for_each_dev(dev, &ap->link, ENABLED) {
+ if (dev->horkage & ATA_HORKAGE_NOLPM) {
+ count = -EOPNOTSUPP;
+ goto out_unlock;
+ }
+ }
+ }
+
ap->target_lpm_policy = policy;
ata_port_schedule_eh(ap);
+out_unlock:
spin_unlock_irqrestore(ap->lock, flags);
-
return count;
}
return;
}
+ /*
+ * XXX - UGLY HACK
+ *
+ * The block layer suspend/resume path is fundamentally broken due
+ * to freezable kthreads and workqueue and may deadlock if a block
+ * device gets removed while resume is in progress. I don't know
+ * what the solution is short of removing freezable kthreads and
+ * workqueues altogether.
+ *
+ * The following is an ugly hack to avoid kicking off device
+ * removal while freezer is active. This is a joke but does avoid
+ * this particular deadlock scenario.
+ *
+ * https://bugzilla.kernel.org/show_bug.cgi?id=62801
+ * http://marc.info/?l=linux-kernel&m=138695698516487
+ */
+#ifdef CONFIG_FREEZER
+ while (pm_freezing)
+ msleep(10);
+#endif
+
DPRINTK("ENTER\n");
mutex_lock(&ap->scsi_scan_mutex);