Firstly we have to make sure that all pending admin commands to
one same scsi_device are completed before removing the scsi_device.
Secondly scsi_internal_device_block() needs this too.
So introduce one waitqueue and atomic counter for this purpose.
Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Bart Van Assche <bart.vanassche@xxxxxxx>
Cc: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Cc: Johannes Thumshirn <jthumshirn@xxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: "James E.J. Bottomley" <jejb@xxxxxxxxxxxxxxxxxx>
Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>
Cc: linux-scsi@xxxxxxxxxxxxxxx
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
drivers/scsi/scsi_lib.c | 6 ++++++
drivers/scsi/scsi_scan.c | 1 +
drivers/scsi/scsi_sysfs.c | 1 +
include/scsi/scsi_device.h | 4 ++++
4 files changed, 12 insertions(+)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 87448526c8c9..bfb2356e41fa 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -299,6 +299,8 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
req->cmd_flags |= flags;
req->rq_flags |= rq_flags | RQF_QUIET;
+ atomic_inc(&sdev->nr_admin_pending);
+
/*
* head injection *required* here otherwise quiesce won't work
*/
@@ -323,6 +325,9 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
out:
blk_put_request(req);
+ atomic_dec(&sdev->nr_admin_pending);
+ wake_up_all(&sdev->admin_wq);
+
return ret;
}
EXPORT_SYMBOL(__scsi_execute);
@@ -3196,6 +3201,7 @@ static int scsi_internal_device_block(struct scsi_device *sdev)
else
scsi_wait_for_queuecommand(sdev);
}
+ wait_event(sdev->admin_wq, !atomic_read(&sdev->nr_admin_pending));
mutex_unlock(&sdev->state_mutex);
return err;
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 0880d975eed3..b10af1692ddd 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -243,6 +243,7 @@ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
mutex_init(&sdev->inquiry_mutex);
INIT_WORK(&sdev->event_work, scsi_evt_thread);
INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
+ init_waitqueue_head(&sdev->admin_wq);
sdev->sdev_gendev.parent = get_device(&starget->dev);
sdev->sdev_target = starget;
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 7943b762c12d..7e03a420dfe7 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -1377,6 +1377,7 @@ void __scsi_remove_device(struct scsi_device *sdev)
blk_cleanup_queue(sdev->request_queue);
cancel_work_sync(&sdev->requeue_work);
+ wait_event(sdev->admin_wq, !atomic_read(&sdev->nr_admin_pending));
if (sdev->host->hostt->slave_destroy)
sdev->host->hostt->slave_destroy(sdev);
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 202f4d6a4342..f6820da1dc37 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -227,6 +227,10 @@ struct scsi_device {
struct mutex state_mutex;
enum scsi_device_state sdev_state;
struct task_struct *quiesced_by;
+
+ atomic_t nr_admin_pending;
+ wait_queue_head_t admin_wq;
+
unsigned long sdev_data[0];
} __attribute__((aligned(sizeof(unsigned long))));
--
2.9.5
