scsi: sd: Fix TCG OPAL unlock on system resume

Commit 3cc2ffe5c16d ("scsi: sd: Differentiate system and runtime start/stop
management") introduced the manage_system_start_stop scsi_device flag to
allow libata to indicate to the SCSI disk driver that nothing should be
done when resuming a disk on system resume. This change turned the
execution of sd_resume() into a no-op for ATA devices on system
resume. While this solved deadlock issues during device resume, this change
also wrongly removed the execution of opal_unlock_from_suspend().  As a
result, devices with TCG OPAL locking enabled remain locked and
inaccessible after a system resume from sleep.

To fix this issue, introduce the SCSI driver resume method and implement it
with the sd_resume() function calling opal_unlock_from_suspend(). The
former sd_resume() function is renamed to sd_resume_common() and modified
to call the new sd_resume() function. For non-ATA devices, this result in
no functional changes.

In order for libata to explicitly execute sd_resume() when a device is
resumed during system restart, the function scsi_resume_device() is
introduced. libata calls this function from the revalidation work executed
on devie resume, a state that is indicated with the new device flag
ATA_DFLAG_RESUMING. Doing so, locked TCG OPAL enabled devices are unlocked
on resume, allowing normal operation.

Fixes: 3cc2ffe5c16d ("scsi: sd: Differentiate system and runtime start/stop management")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=218538
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240319071209.1179257-1-dlemoal@kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index b0d6e69c4a5b..214b935c2ced 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -712,8 +712,10 @@ void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 				ehc->saved_ncq_enabled |= 1 << devno;
 
 			/* If we are resuming, wake up the device */
-			if (ap->pflags & ATA_PFLAG_RESUMING)
+			if (ap->pflags & ATA_PFLAG_RESUMING) {
+				dev->flags |= ATA_DFLAG_RESUMING;
 				ehc->i.dev_action[devno] |= ATA_EH_SET_ACTIVE;
+			}
 		}
 	}
 
@@ -3169,6 +3171,7 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
 	return 0;
 
  err:
+	dev->flags &= ~ATA_DFLAG_RESUMING;
 	*r_failed_dev = dev;
 	return rc;
 }