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

Commit 6600593cbd ("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>

Documentation/scsi/scsi_eh.rst

@@ -92,14 +92,17 @@ The timeout handler is scsi_timeout().  When a timeout occurs, this function
  1. invokes optional hostt->eh_timed_out() callback.  Return value can
     be one of
 
-    - BLK_EH_RESET_TIMER
+    - SCSI_EH_RESET_TIMER
 	This indicates that more time is required to finish the
 	command.  Timer is restarted.
 
-    - BLK_EH_DONE
+    - SCSI_EH_NOT_HANDLED
         eh_timed_out() callback did not handle the command.
 	Step #2 is taken.
 
+    - SCSI_EH_DONE
+        eh_timed_out() completed the command.
+
  2. scsi_abort_command() is invoked to schedule an asynchronous abort which may
     issue a retry scmd->allowed + 1 times.  Asynchronous aborts are not invoked
     for commands for which the SCSI_EH_ABORT_SCHEDULED flag is set (this