diff options
| author | Damien Le Moal <dlemoal@kernel.org> | 2023-09-15 10:02:41 +0900 |
|---|---|---|
| committer | Damien Le Moal <dlemoal@kernel.org> | 2023-09-28 21:23:00 +0900 |
| commit | 3cc2ffe5c16dc65dfac354bc5b5bc98d3b397567 (patch) | |
| tree | dbd8aa9961cfe03d0be8d79f5e50abc44bbef12a /include/scsi | |
| parent | fb99ef17865035a6657786d4b2af11a27ba23f9b (diff) | |
scsi: sd: Differentiate system and runtime start/stop management
The underlying device and driver of a SCSI disk may have different
system and runtime power mode control requirements. This is because
runtime power management affects only the SCSI disk, while system level
power management affects all devices, including the controller for the
SCSI disk.
For instance, issuing a START STOP UNIT command when a SCSI disk is
runtime suspended and resumed is fine: the command is translated to a
STANDBY IMMEDIATE command to spin down the ATA disk and to a VERIFY
command to wake it up. The SCSI disk runtime operations have no effect
on the ata port device used to connect the ATA disk. However, for
system suspend/resume operations, the ATA port used to connect the
device will also be suspended and resumed, with the resume operation
requiring re-validating the device link and the device itself. In this
case, issuing a VERIFY command to spinup the disk must be done before
starting to revalidate the device, when the ata port is being resumed.
In such case, we must not allow the SCSI disk driver to issue START STOP
UNIT commands.
Allow a low level driver to refine the SCSI disk start/stop management
by differentiating system and runtime cases with two new SCSI device
flags: manage_system_start_stop and manage_runtime_start_stop. These new
flags replace the current manage_start_stop flag. Drivers setting the
manage_start_stop are modifed to set both new flags, thus preserving the
existing start/stop management behavior. For backward compatibility, the
old manage_start_stop sysfs device attribute is kept as a read-only
attribute showing a value of 1 for devices enabling both new flags and 0
otherwise.
Fixes: 0a8589055936 ("ata,scsi: do not issue START STOP UNIT on resume")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'include/scsi')
| -rw-r--r-- | include/scsi/scsi_device.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index b9230b6add04..fd41fdac0a8e 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -161,6 +161,10 @@ struct scsi_device { * pass settings from slave_alloc to scsi * 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 */ + unsigned removable:1; unsigned changed:1; /* Data invalid due to media change */ unsigned busy:1; /* Used to prevent races */ @@ -193,7 +197,6 @@ struct scsi_device { unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */ unsigned no_start_on_add:1; /* do not issue start on add */ unsigned allow_restart:1; /* issue START_UNIT in error handler */ - unsigned manage_start_stop:1; /* Let HLD (sd) manage start/stop */ unsigned no_start_on_resume:1; /* Do not issue START_STOP_UNIT on resume */ unsigned start_stop_pwr_cond:1; /* Set power cond. in START_STOP_UNIT */ unsigned no_uld_attach:1; /* disable connecting to upper level drivers */ |