diff mbox series

[10/13] scsi:scsi_error: Define helper to perform target based error handle

Message ID 20230723234422.1629194-11-haowenchao2@huawei.com
State New
Headers show
Series scsi: Support LUN/target based error handle | expand

Commit Message

Wenchao Hao July 23, 2023, 11:44 p.m. UTC
It is an simple target based error handle strategy, it try
target based recovery first, including check sense, start unit,
reset lun and reset target.

This is an simple error handle strategy which can be used by drivers
or other target based error handlers.

Signed-off-by: Wenchao Hao <haowenchao2@huawei.com>
---
 drivers/scsi/scsi_error.c | 129 ++++++++++++++++++++++++++++++++++++++
 include/scsi/scsi_eh.h    |   2 +
 2 files changed, 131 insertions(+)
diff mbox series

Patch

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index bb6f05ba199b..6ebf62f9817a 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -2531,6 +2531,135 @@  int scsi_sdev_eh(struct scsi_device *sdev,
 }
 EXPORT_SYMBOL_GPL(scsi_sdev_eh);
 
+static int starget_eh_stu(struct scsi_target *starget,
+			  struct list_head *work_q,
+			  struct list_head *done_q)
+{
+	struct scsi_device *sdev;
+	struct scsi_cmnd *scmd, *stu_scmd;
+
+	list_for_each_entry(sdev, &starget->devices, same_target_siblings) {
+		if (sdev_stu_done(sdev))
+			continue;
+
+		stu_scmd = NULL;
+		list_for_each_entry(scmd, work_q, eh_entry)
+			if (scmd->device == sdev && SCSI_SENSE_VALID(scmd) &&
+			    scsi_check_sense(scmd) == FAILED) {
+				stu_scmd = scmd;
+				break;
+			}
+		if (!stu_scmd)
+			continue;
+
+		if (scsi_eh_sdev_stu(stu_scmd, work_q, done_q))
+			return 1;
+	}
+
+	return 0;
+}
+
+static int starget_eh_reset_lun(struct scsi_target *starget,
+				struct list_head *work_q,
+				struct list_head *done_q)
+{
+	struct scsi_device *sdev;
+	struct scsi_cmnd *scmd, *bdr_scmd;
+
+	list_for_each_entry(sdev, &starget->devices, same_target_siblings) {
+		if (sdev_reset_done(sdev))
+			continue;
+
+		bdr_scmd = NULL;
+		list_for_each_entry(scmd, work_q, eh_entry)
+			if (scmd->device) {
+				bdr_scmd = scmd;
+				break;
+			}
+		if (!bdr_scmd)
+			continue;
+
+		if (scsi_eh_sdev_reset(bdr_scmd, work_q, done_q))
+			return 1;
+	}
+
+	return 0;
+}
+
+static int starget_eh_reset_target(struct scsi_target *starget,
+				    struct list_head *work_q,
+				    struct list_head *done_q)
+{
+	enum scsi_disposition rtn;
+	struct scsi_cmnd *scmd, *next;
+	LIST_HEAD(check_list);
+
+	scmd = list_first_entry(work_q, struct scsi_cmnd, eh_entry);
+
+	SCSI_LOG_ERROR_RECOVERY(3, starget_printk(KERN_INFO, starget,
+			     "%s: Sending target reset\n", current->comm));
+
+	rtn = scsi_try_target_reset(scmd);
+	if (rtn != SUCCESS && rtn != FAST_IO_FAIL) {
+		SCSI_LOG_ERROR_RECOVERY(3, starget_printk(KERN_INFO, starget,
+				     "%s: Target reset failed\n",
+				     current->comm));
+		return 0;
+	}
+
+	SCSI_LOG_ERROR_RECOVERY(3, starget_printk(KERN_INFO, starget,
+			     "%s: Target reset success\n", current->comm));
+
+	list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
+		if (rtn == SUCCESS)
+			list_move_tail(&scmd->eh_entry, &check_list);
+		else if (rtn == FAST_IO_FAIL)
+			scsi_eh_finish_cmd(scmd, done_q);
+	}
+
+	return scsi_eh_test_devices(&check_list, work_q, done_q, 0);
+}
+
+/*
+ * Target based error handle
+ *
+ * @work_q: list of scsi commands need to recovery
+ * @done_q: list of scsi commands handled
+ *
+ * return: return 1 if all commands in work_q is recoveryed, else 0 is returned
+ */
+int scsi_starget_eh(struct scsi_target *starget,
+		    struct list_head *work_q,
+		    struct list_head *done_q)
+{
+	int ret = 0;
+
+	SCSI_LOG_ERROR_RECOVERY(2, starget_printk(KERN_INFO, starget,
+		"%s:targeteh: checking sense\n", current->comm));
+	ret = scsi_eh_get_sense(work_q, done_q);
+	if (ret)
+		return ret;
+
+	SCSI_LOG_ERROR_RECOVERY(2, starget_printk(KERN_INFO, starget,
+		"%s:targeteh: start unit\n", current->comm));
+	ret = starget_eh_stu(starget, work_q, done_q);
+	if (ret)
+		return ret;
+
+	SCSI_LOG_ERROR_RECOVERY(2, starget_printk(KERN_INFO, starget,
+		"%s:targeteh reset LUN\n", current->comm));
+	ret = starget_eh_reset_lun(starget, work_q, done_q);
+	if (ret)
+		return ret;
+
+	SCSI_LOG_ERROR_RECOVERY(2, starget_printk(KERN_INFO, starget,
+		"%s:targeteh reset target\n", current->comm));
+	ret = starget_eh_reset_target(starget, work_q, done_q);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(scsi_starget_eh);
+
 /*
  * Function:    scsi_report_bus_reset()
  *
diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h
index 030b22a8c164..f8f3a143d848 100644
--- a/include/scsi/scsi_eh.h
+++ b/include/scsi/scsi_eh.h
@@ -20,6 +20,8 @@  extern bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd,
 extern enum scsi_disposition scsi_check_sense(struct scsi_cmnd *);
 extern int scsi_sdev_eh(struct scsi_device *, struct list_head *,
 			struct list_head *);
+extern int scsi_starget_eh(struct scsi_target *, struct list_head *,
+			struct list_head *);
 
 static inline bool scsi_sense_is_deferred(const struct scsi_sense_hdr *sshdr)
 {