---

yaml
---
r: 71728
b: refs/heads/master
c: fe97e2a
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 16ebbf358477b762115fec2f85d9b9496a5cae76
+refs/heads/master: fe97e2aa0502922488ad62303a19a20c8044ae18

trunk/drivers/md/dm-mpath-hp-sw.c

@@ -18,18 +18,53 @@
 #include <linux/types.h>
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_dbg.h>
 
 #include "dm.h"
 #include "dm-hw-handler.h"
 
 #define DM_MSG_PREFIX "multipath hp-sw"
 #define DM_HP_HWH_NAME "hp-sw"
-#define DM_HP_HWH_VER "0.0.3"
+#define DM_HP_HWH_VER "1.0.0"
 
 struct hp_sw_context {
 	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
 };
 
+/*
+ * hp_sw_error_is_retryable - Is an HP-specific check condition retryable?
+ * @req: path activation request
+ *
+ * Examine error codes of request and determine whether the error is retryable.
+ * Some error codes are already retried by scsi-ml (see
+ * scsi_decide_disposition), but some HP specific codes are not.
+ * The intent of this routine is to supply the logic for the HP specific
+ * check conditions.
+ *
+ * Returns:
+ *  1 - command completed with retryable error
+ *  0 - command completed with non-retryable error
+ *
+ * Possible optimizations
+ * 1. More hardware-specific error codes
+ */
+static int hp_sw_error_is_retryable(struct request *req)
+{
+	/*
+	 * NOT_READY is known to be retryable
+	 * For now we just dump out the sense data and call it retryable
+	 */
+	if (status_byte(req->errors) == CHECK_CONDITION)
+		__scsi_print_sense(DM_HP_HWH_NAME, req->sense, req->sense_len);
+
+	/*
+	 * At this point we don't have complete information about all the error
+	 * codes from this hardware, so we are just conservative and retry
+	 * when in doubt.
+	 */
+	return 1;
+}
+
 /*
  * hp_sw_end_io - Completion handler for HP path activation.
  * @req: path activation request
@@ -40,23 +75,30 @@ struct hp_sw_context {
  *
  * Context: scsi-ml softirq
  *
- * Possible optimizations
- * 1. Actually check sense data for retryable error (e.g. NOT_READY)
  */
 static void hp_sw_end_io(struct request *req, int error)
 {
 	struct dm_path *path = req->end_io_data;
 	unsigned err_flags = 0;
 
-	if (!error)
+	if (!error) {
 		DMDEBUG("%s path activation command - success",
 			path->dev->name);
-	else {
-		DMWARN("%s path activation command - error=0x%x",
-		       path->dev->name, error);
-		err_flags = MP_FAIL_PATH;
+		goto out;
 	}
 
+	if (hp_sw_error_is_retryable(req)) {
+		DMDEBUG("%s path activation command - retry",
+			path->dev->name);
+		err_flags = MP_RETRY;
+		goto out;
+	}
+
+	DMWARN("%s path activation fail - error=0x%x",
+	       path->dev->name, error);
+	err_flags = MP_FAIL_PATH;
+
+out:
 	req->end_io_data = NULL;
 	__blk_put_request(req->q, req);
 	dm_pg_init_complete(path, err_flags);
@@ -135,16 +177,16 @@ static void hp_sw_pg_init(struct hw_handler *hwh, unsigned bypassed,
 	if (!req) {
 		DMERR("%s path activation command - allocation fail",
 		      path->dev->name);
-		goto fail;
+		goto retry;
 	}
 
 	DMDEBUG("%s path activation command - sent", path->dev->name);
 
 	blk_execute_rq_nowait(req->q, NULL, req, 1, hp_sw_end_io);
 	return;
 
-fail:
-	dm_pg_init_complete(path, MP_FAIL_PATH);
+retry:
+	dm_pg_init_complete(path, MP_RETRY);
 }
 
 static int hp_sw_create(struct hw_handler *hwh, unsigned argc, char **argv)