scsi: sd: Introduce manage_shutdown device flag
authorDamien Le Moal <dlemoal@kernel.org>
Wed, 25 Oct 2023 06:46:12 +0000 (15:46 +0900)
committerDamien Le Moal <dlemoal@kernel.org>
Fri, 27 Oct 2023 01:00:19 +0000 (10:00 +0900)
Commit aa3998dbeb3a ("ata: libata-scsi: Disable scsi device
manage_system_start_stop") change setting the manage_system_start_stop
flag to false for libata managed disks to enable libata internal
management of disk suspend/resume. However, a side effect of this change
is that on system shutdown, disks are no longer being stopped (set to
standby mode with the heads unloaded). While this is not a critical
issue, this unclean shutdown is not recommended and shows up with
increased smart counters (e.g. the unexpected power loss counter
"Unexpect_Power_Loss_Ct").

Instead of defining a shutdown driver method for all ATA adapter
drivers (not all of them define that operation), this patch resolves
this issue by further refining the sd driver start/stop control of disks
using the new flag manage_shutdown. If this new flag is set to true by
a low level driver, the function sd_shutdown() will issue a
START STOP UNIT command with the start argument set to 0 when a disk
needs to be powered off (suspended) on system power off, that is, when
system_state is equal to SYSTEM_POWER_OFF.

Similarly to the other manage_xxx flags, the new manage_shutdown flag is
exposed through sysfs as a read-write device attribute.

To avoid any confusion between manage_shutdown and
manage_system_start_stop, the comments describing these flags in
include/scsi/scsi.h are also improved.

Fixes: aa3998dbeb3a ("ata: libata-scsi: Disable scsi device manage_system_start_stop")
Cc: stable@vger.kernel.org
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218038
Link: https://lore.kernel.org/all/cd397c88-bf53-4768-9ab8-9d107df9e613@gmail.com/
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/ata/libata-scsi.c
drivers/firewire/sbp2.c
drivers/scsi/sd.c
include/scsi/scsi_device.h

index a371b49..3a957c4 100644 (file)
@@ -1053,10 +1053,11 @@ int ata_scsi_dev_config(struct scsi_device *sdev, struct ata_device *dev)
 
                /*
                 * Ask the sd driver to issue START STOP UNIT on runtime suspend
-                * and resume only. For system level suspend/resume, devices
-                * power state is handled directly by libata EH.
+                * and resume and shutdown only. For system level suspend/resume,
+                * devices power state is handled directly by libata EH.
                 */
                sdev->manage_runtime_start_stop = true;
+               sdev->manage_shutdown = true;
        }
 
        /*
index 749868b..7edf2c9 100644 (file)
@@ -1521,6 +1521,7 @@ static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
        if (sbp2_param_exclusive_login) {
                sdev->manage_system_start_stop = true;
                sdev->manage_runtime_start_stop = true;
+               sdev->manage_shutdown = true;
        }
 
        if (sdev->type == TYPE_ROM)
index 83b6a3f..6effa13 100644 (file)
@@ -209,7 +209,8 @@ manage_start_stop_show(struct device *dev,
 
        return sysfs_emit(buf, "%u\n",
                          sdp->manage_system_start_stop &&
-                         sdp->manage_runtime_start_stop);
+                         sdp->manage_runtime_start_stop &&
+                         sdp->manage_shutdown);
 }
 static DEVICE_ATTR_RO(manage_start_stop);
 
@@ -275,6 +276,35 @@ manage_runtime_start_stop_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(manage_runtime_start_stop);
 
+static ssize_t manage_shutdown_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_shutdown);
+}
+
+static ssize_t manage_shutdown_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_shutdown = v;
+
+       return count;
+}
+static DEVICE_ATTR_RW(manage_shutdown);
+
 static ssize_t
 allow_restart_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
@@ -607,6 +637,7 @@ static struct attribute *sd_disk_attrs[] = {
        &dev_attr_manage_start_stop.attr,
        &dev_attr_manage_system_start_stop.attr,
        &dev_attr_manage_runtime_start_stop.attr,
+       &dev_attr_manage_shutdown.attr,
        &dev_attr_protection_type.attr,
        &dev_attr_protection_mode.attr,
        &dev_attr_app_tag_own.attr,
@@ -3819,8 +3850,10 @@ static void sd_shutdown(struct device *dev)
                sd_sync_cache(sdkp, NULL);
        }
 
-       if (system_state != SYSTEM_RESTART &&
-           sdkp->device->manage_system_start_stop) {
+       if ((system_state != SYSTEM_RESTART &&
+            sdkp->device->manage_system_start_stop) ||
+           (system_state == SYSTEM_POWER_OFF &&
+            sdkp->device->manage_shutdown)) {
                sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
                sd_start_stop_device(sdkp, 0);
        }
index fd41fda..65e49fa 100644 (file)
@@ -162,8 +162,24 @@ struct scsi_device {
                                 * core. */
        unsigned int eh_timeout; /* Error handling timeout */
 
-       bool manage_system_start_stop; /* Let HLD (sd) manage system start/stop */
-       bool manage_runtime_start_stop; /* Let HLD (sd) manage runtime start/stop */
+       /*
+        * If true, let the high-level device driver (sd) manage the device
+        * power state for system suspend/resume (suspend to RAM and
+        * hibernation) operations.
+        */
+       bool manage_system_start_stop;
+
+       /*
+        * If true, let the high-level device driver (sd) manage the device
+        * power state for runtime device suspand and resume operations.
+        */
+       bool manage_runtime_start_stop;
+
+       /*
+        * If true, let the high-level device driver (sd) manage the device
+        * power state for system shutdown (power off) operations.
+        */
+       bool manage_shutdown;
 
        unsigned removable:1;
        unsigned changed:1;     /* Data invalid due to media change */