[PATCH] SCSI: Introduce scsi_req_abort_cmd (REPOST)

Introduce scsi_req_abort_cmd(struct scsi_cmnd *).
This function requests that SCSI Core start recovery for the
command by deleting the timer and adding the command to the eh
queue.  It can be called by either LLDDs or SCSI Core.  LLDDs who
implement their own error recovery MAY ignore the timeout event if
they generated scsi_req_abort_cmd.

First post:
http://marc.theaimsgroup.com/?l=linux-scsi&m=113833937421677&w=2

Signed-off-by: Luben Tuikov <ltuikov@yahoo.com>

Signed-off-by: Tejun Heo <htejun@gmail.com>

drivers/scsi/scsi.c

@@ -719,6 +719,24 @@ void scsi_init_cmd_from_req(struct scsi_cmnd *cmd, struct scsi_request *sreq)
  */
 static DEFINE_PER_CPU(struct list_head, scsi_done_q);
 
+/**
+ * scsi_req_abort_cmd -- Request command recovery for the specified command
+ * cmd: pointer to the SCSI command of interest
+ *
+ * This function requests that SCSI Core start recovery for the
+ * command by deleting the timer and adding the command to the eh
+ * queue.  It can be called by either LLDDs or SCSI Core.  LLDDs who
+ * implement their own error recovery MAY ignore the timeout event if
+ * they generated scsi_req_abort_cmd.
+ */
+void scsi_req_abort_cmd(struct scsi_cmnd *cmd)
+{
+	if (!scsi_delete_timer(cmd))
+		return;
+	scsi_times_out(cmd);
+}
+EXPORT_SYMBOL(scsi_req_abort_cmd);
+
 /**
  * scsi_done - Enqueue the finished SCSI command into the done queue.
  * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives

include/scsi/scsi_cmnd.h

@@ -151,5 +151,6 @@ extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t);
 extern void scsi_put_command(struct scsi_cmnd *);
 extern void scsi_io_completion(struct scsi_cmnd *, unsigned int, unsigned int);
 extern void scsi_finish_command(struct scsi_cmnd *cmd);
+extern void scsi_req_abort_cmd(struct scsi_cmnd *cmd);
 
 #endif /* _SCSI_SCSI_CMND_H */