[PATCH 4/5] scsi: Added routine to set SCMD_NORETRIES_ABORT bit for outstanding io on scsi_dev

[Muneendra <muneendra.kumar@broadcom.com>]

Added a new routine scsi_set_noretries_abort_io_device()to set
SCMD_NORETRIES_ABORT for all the inflight/pending IO's on a particular
scsi device at that particular instant.

Export the symbol so the routine can be called by scsi_transport_fc.c

Added new function declaration scsi_set_noretries_abort_io_device in
scsi_priv.h

Signed-off-by: Muneendra <muneendra.kumar@broadcom.com>
---
 drivers/scsi/scsi_error.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/scsi_priv.h  |  1 +
 2 files changed, 54 insertions(+)

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 3222496..938d770 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -271,6 +271,59 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
 	call_rcu(&scmd->rcu, scsi_eh_inc_host_failed);
 }
 
+static bool
+scsi_set_noretries_abort_io(struct request *rq, void *priv, bool reserved)
+{
+	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
+	struct scsi_device *sdev = scmd->device;
+
+	/* only set SCMD_NORETRIES_ABORT on ios on a specific sdev */
+	if (sdev != priv)
+		return true;
+	/* we don't want this command reissued on abort success
+	 * so set SCMD_NORETRIES_ABORT bit to ensure it
+	 * won't get reissued
+	 */
+	if (READ_ONCE(rq->state) == MQ_RQ_IN_FLIGHT)
+		set_bit(SCMD_NORETRIES_ABORT, &scmd->state);
+	return true;
+}
+
+static int
+__scsi_set_noretries_abort_io_device(struct scsi_device *sdev)
+{
+
+	if (sdev->sdev_state != SDEV_RUNNING)
+		return -EINVAL;
+
+	if (blk_queue_init_done(sdev->request_queue)) {
+
+		blk_mq_quiesce_queue(sdev->request_queue);
+		blk_mq_tagset_busy_iter(&sdev->host->tag_set,
+				scsi_set_noretries_abort_io, sdev);
+		blk_mq_unquiesce_queue(sdev->request_queue);
+	}
+	return 0;
+}
+
+/*
+ * scsi_set_noretries_abort_io_device - set the SCMD_NORETRIES_ABORT
+ * bit for all the pending io's on a device
+ * @sdev:	scsi_device
+ */
+int
+scsi_set_noretries_abort_io_device(struct scsi_device *sdev)
+{
+	struct Scsi_Host *shost = sdev->host;
+	int ret  = -EINVAL;
+
+	mutex_lock(&shost->scan_mutex);
+	ret = __scsi_set_noretries_abort_io_device(sdev);
+	mutex_unlock(&shost->scan_mutex);
+	return ret;
+}
+EXPORT_SYMBOL(scsi_set_noretries_abort_io_device);
+
 /**
  * scsi_times_out - Timeout function for normal scsi commands.
  * @req:	request that is timing out.
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index d12ada0..1bbffd3 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -81,6 +81,7 @@ void scsi_eh_ready_devs(struct Scsi_Host *shost,
 int scsi_eh_get_sense(struct list_head *work_q,
 		      struct list_head *done_q);
 int scsi_noretry_cmd(struct scsi_cmnd *scmd);
+extern int scsi_set_noretries_abort_io_device(struct scsi_device *sdev);
 
 /* scsi_lib.c */
 extern int scsi_maybe_unblock_host(struct scsi_device *sdev);
-- 
1.8.3.1