[PATCH v2 1/2] scsi: sd: Add manage_restart device attribute to scsi_disk

Markus Probst
2025-10-09T11:24:50Z

In addition to the already existing manage_shutdown,
manage_system_start_stop and manage_runtime_start_stop device
scsi_disk attributes, add manage_restart, which allows the high-level
device driver (sd) to manage the device power state for SYSTEM_RESTART if set to 1.

Signed-off-by: Markus Probst <markus.probst@posteo.de>
---
drivers/scsi/sd.c | 35 ++++++++++++++++++++++++++++++++++-
include/scsi/scsi_device.h | 6 ++++++
2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 5b8668accf8e..a3e9c2e9d9f4 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -318,6 +318,36 @@ static ssize_t manage_shutdown_store(struct device *dev,
}
static DEVICE_ATTR_RW(manage_shutdown);

+static ssize_t manage_restart_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct scsi_disk *sdkp = to_scsi_disk(dev);
+ struct scsi_device *sdp = sdkp->device;
+
+ return sysfs_emit(buf, "%u\n", sdp->manage_restart);
+}
+
+
+static ssize_t manage_restart_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct scsi_disk *sdkp = to_scsi_disk(dev);
+ struct scsi_device *sdp = sdkp->device;
+ bool v;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ if (kstrtobool(buf, &v))
+ return -EINVAL;
+
+ sdp->manage_restart = v;
+
+ return count;
+}
+static DEVICE_ATTR_RW(manage_restart);
+
static ssize_t
allow_restart_show(struct device *dev, struct device_attribute *attr, char *buf)
{
@@ -654,6 +684,7 @@ static struct attribute *sd_disk_attrs[] = {
&dev_attr_manage_system_start_stop.attr,
&dev_attr_manage_runtime_start_stop.attr,
&dev_attr_manage_shutdown.attr,
+ &dev_attr_manage_restart.attr,
&dev_attr_protection_type.attr,
&dev_attr_protection_mode.attr,
&dev_attr_app_tag_own.attr,
@@ -4175,7 +4206,9 @@ static void sd_shutdown(struct device *dev)
(system_state == SYSTEM_POWER_OFF &&
sdkp->device->manage_shutdown) ||
(system_state == SYSTEM_RUNNING &&
- sdkp->device->manage_runtime_start_stop)) {
+ sdkp->device->manage_runtime_start_stop) ||
+ (system_state == SYSTEM_RESTART &&
+ sdkp->device->manage_restart)) {
sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
sd_start_stop_device(sdkp, 0);
}
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 6d6500148c4b..c7e657ac8b6d 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -178,6 +178,12 @@ struct scsi_device {
*/
unsigned manage_shutdown:1;

+ /*
+ * If true, let the high-level device driver (sd) manage the device
+ * power state for system restart (reboot) operations.
+ */
+ unsigned manage_restart:1;
+
/*
* If set and if the device is runtime suspended, ask the high-level
* device driver (sd) to force a runtime resume of the device.
--
2.49.1