scsi: core: Change the return type of .eh_timed_out()

Commit 6600593cbd93 ("block: rename BLK_EH_NOT_HANDLED to BLK_EH_DONE")
made it impossible for .eh_timed_out() implementations to call
scsi_done() without causing a crash.

Restore support for SCSI timeout handlers to call scsi_done() as follows:

 * Change all .eh_timed_out() handlers as follows:

   - Change the return type into enum scsi_timeout_action.
   - Change BLK_EH_RESET_TIMER into SCSI_EH_RESET_TIMER.
   - Change BLK_EH_DONE into SCSI_EH_NOT_HANDLED.

 * In scsi_timeout(), convert the SCSI_EH_* values into BLK_EH_* values.

Reviewed-by: Lee Duncan <lduncan@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221018202958.1902564-3-bvanassche@acm.org
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 19 insertions, 14 deletions

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 02520f912306..be2a70c5ac6d 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -328,7 +328,6 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
 enum blk_eh_timer_return scsi_timeout(struct request *req)
 {
 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
-	enum blk_eh_timer_return rtn = BLK_EH_DONE;
 	struct Scsi_Host *host = scmd->device->host;
 
 	trace_scsi_dispatch_cmd_timeout(scmd);
@@ -338,23 +337,29 @@ enum blk_eh_timer_return scsi_timeout(struct request *req)
 	if (host->eh_deadline != -1 && !host->last_reset)
 		host->last_reset = jiffies;
 
-	if (host->hostt->eh_timed_out)
-		rtn = host->hostt->eh_timed_out(scmd);
-
-	if (rtn == BLK_EH_DONE) {
-		/*
-		 * If scsi_done() has already set SCMD_STATE_COMPLETE, do not
-		 * modify *scmd.
-		 */
-		if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))
+	if (host->hostt->eh_timed_out) {
+		switch (host->hostt->eh_timed_out(scmd)) {
+		case SCSI_EH_DONE:
 			return BLK_EH_DONE;
-		if (scsi_abort_command(scmd) != SUCCESS) {
-			set_host_byte(scmd, DID_TIME_OUT);
-			scsi_eh_scmd_add(scmd);
+		case SCSI_EH_RESET_TIMER:
+			return BLK_EH_RESET_TIMER;
+		case SCSI_EH_NOT_HANDLED:
+			break;
 		}
 	}
 
-	return rtn;
+	/*
+	 * If scsi_done() has already set SCMD_STATE_COMPLETE, do not modify
+	 * *scmd.
+	 */
+	if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))
+		return BLK_EH_DONE;
+	if (scsi_abort_command(scmd) != SUCCESS) {
+		set_host_byte(scmd, DID_TIME_OUT);
+		scsi_eh_scmd_add(scmd);
+	}
+
+	return BLK_EH_DONE;
 }
 
 /**