[PATCH AUTOSEL 5.10 12/17] scsi: core: Only process PM requests if rpm_status != RPM_ACTIVE

Sasha Levin
2021-01-05T01:06:32Z

From: Bart Van Assche <bvanassche@acm.org>

[ Upstream commit e6044f714b256259df9611ff49af433e5411c5c8 ]

Instead of submitting all SCSI commands submitted with scsi_execute() to a
SCSI device if rpm_status != RPM_ACTIVE, only submit RQF_PM (power
management requests) if rpm_status != RPM_ACTIVE. This patch makes the SCSI
core handle the runtime power management status (rpm_status) as it should
be handled.

Link: https://lore.kernel.org/r/20201209052951.16136-7-bvanassche@acm.org
Cc: Can Guo <cang@codeaurora.org>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Martin Kepplinger <martin.kepplinger@puri.sm>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/scsi_lib.c | 27 ++++++++++++++-------------
1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 2d17137f8ff3b..31d7a6ddc9db7 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -249,7 +249,8 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,

req = blk_get_request(sdev->request_queue,
data_direction == DMA_TO_DEVICE ?
- REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, BLK_MQ_REQ_PREEMPT);
+ REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN,
+ rq_flags & RQF_PM ? BLK_MQ_REQ_PM : 0);
if (IS_ERR(req))
return ret;
rq = scsi_req(req);
@@ -1203,6 +1204,8 @@ static blk_status_t
scsi_device_state_check(struct scsi_device *sdev, struct request *req)
{
switch (sdev->sdev_state) {
+ case SDEV_CREATED:
+ return BLK_STS_OK;
case SDEV_OFFLINE:
case SDEV_TRANSPORT_OFFLINE:
/*
@@ -1229,18 +1232,18 @@ scsi_device_state_check(struct scsi_device *sdev, struct request *req)
return BLK_STS_RESOURCE;
case SDEV_QUIESCE:
/*
- * If the devices is blocked we defer normal commands.
+ * If the device is blocked we only accept power management
+ * commands.
*/
- if (req && !(req->rq_flags & RQF_PREEMPT))
+ if (req && WARN_ON_ONCE(!(req->rq_flags & RQF_PM)))
return BLK_STS_RESOURCE;
return BLK_STS_OK;
default:
/*
* For any other not fully online state we only allow
- * special commands. In particular any user initiated
- * command is not allowed.
+ * power management commands.
*/
- if (req && !(req->rq_flags & RQF_PREEMPT))
+ if (req && !(req->rq_flags & RQF_PM))
return BLK_STS_IOERR;
return BLK_STS_OK;
}
@@ -2508,15 +2511,13 @@ void sdev_evt_send_simple(struct scsi_device *sdev,
EXPORT_SYMBOL_GPL(sdev_evt_send_simple);

/**
- * scsi_device_quiesce - Block user issued commands.
+ * scsi_device_quiesce - Block all commands except power management.
* @sdev: scsi device to quiesce.
*
* This works by trying to transition to the SDEV_QUIESCE state
* (which must be a legal transition). When the device is in this
- * state, only special requests will be accepted, all others will
- * be deferred. Since special requests may also be requeued requests,
- * a successful return doesn't guarantee the device will be
- * totally quiescent.
+ * state, only power management requests will be accepted, all others will
+ * be deferred.
*
* Must be called with user context, may sleep.
*
@@ -2578,12 +2579,12 @@ void scsi_device_resume(struct scsi_device *sdev)
* device deleted during suspend)
*/
mutex_lock(&sdev->state_mutex);
+ if (sdev->sdev_state == SDEV_QUIESCE)
+ scsi_device_set_state(sdev, SDEV_RUNNING);
if (sdev->quiesced_by) {
sdev->quiesced_by = NULL;
blk_clear_pm_only(sdev->request_queue);
}
- if (sdev->sdev_state == SDEV_QUIESCE)
- scsi_device_set_state(sdev, SDEV_RUNNING);
mutex_unlock(&sdev->state_mutex);
}
EXPORT_SYMBOL(scsi_device_resume);
--
2.27.0