Add a user-facing flag that sets expecting_media_change on runtime
resume. That works around devices that send MEDIA_CHANGED when it
actually is just resumed from suspend and the media can be expected
not to have changed.
Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxx>
---
drivers/scsi/scsi_sysfs.c | 38 ++++++++++++++++++++++++++++++++++++++
include/scsi/scsi_device.h | 2 ++
2 files changed, 40 insertions(+)
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index b6378c8ca783..a049290addff 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -1189,6 +1189,43 @@ static DEVICE_ATTR(queue_ramp_up_period, S_IRUGO | S_IWUSR,
sdev_show_queue_ramp_up_period,
sdev_store_queue_ramp_up_period);
+static ssize_t
+sdev_show_expect_media_change_suspend(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct scsi_device *sdev;
+ sdev = to_scsi_device(dev);
+
+ if (sdev->expect_media_change_suspend)
+ return sprintf(buf, "1\n");
+ else
+ return sprintf(buf, "0\n");
+}
+
+static ssize_t
+sdev_store_expect_media_change_suspend(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct scsi_device *sdev;
+ unsigned int flag;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ sdev = to_scsi_device(dev);
+ err = kstrtouint(buf, 10, &flag);
+ if (err)
+ return err;
+ sdev->expect_media_change_suspend = !!flag;
+
+ return count;
+}
+static DEVICE_ATTR(expect_media_change_suspend, S_IRUGO | S_IWUSR,
+ sdev_show_expect_media_change_suspend,
+ sdev_store_expect_media_change_suspend);
+
static umode_t scsi_sdev_attr_is_visible(struct kobject *kobj,
struct attribute *attr, int i)
{
@@ -1260,6 +1297,7 @@ static struct attribute *scsi_sdev_attrs[] = {
&dev_attr_queue_type.attr,
&dev_attr_wwid.attr,
&dev_attr_blacklist.attr,
+ &dev_attr_expect_media_change_suspend.attr,
#ifdef CONFIG_SCSI_DH
&dev_attr_dh_state.attr,
&dev_attr_access_state.attr,
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index ca2c3eb5830f..fafb8e6ea4d0 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -171,6 +171,8 @@ struct scsi_device {
unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
* because we did a bus reset. */
unsigned expecting_media_change:1; /* Expecting "media changed" UA */
+ unsigned expect_media_change_suspend:1; /* User facing flag to enable
+ * the above flag on runtime resume */
unsigned use_10_for_rw:1; /* first try 10-byte read / write */
unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
unsigned set_dbd_for_ms:1; /* Set "DBD" field in mode sense */
--
2.20.1
