[RFC PATCH v3 12/19] scsi: scsi_debug: Add param to control LUN bassed error handler

[JiangJianJun]

From: Wenchao Hao <haowenchao2@xxxxxxxxxx>

Add new module param lun_eh to control if enable LUN based
error handle, and param lun_eh_fallback to control if fallback
to further recover when LUN recovery can not recover all
error commands. This is used to test the LUN based error handle.

Signed-off-by: Wenchao Hao <haowenchao2@xxxxxxxxxx>
---
 drivers/scsi/scsi_debug.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 5ceaa4665e5d..162728cca99d 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -884,6 +884,8 @@ static bool write_since_sync;
 static bool sdebug_statistics = DEF_STATISTICS;
 static bool sdebug_wp;
 static bool sdebug_allow_restart;
+static bool sdebug_lun_eh;
+static bool sdebug_lun_eh_fallback;
 static enum {
 	BLK_ZONED_NONE	= 0,
 	BLK_ZONED_HA	= 1,
@@ -5885,6 +5887,9 @@ static int scsi_debug_sdev_init(struct scsi_device *sdp)
 		pr_info("sdev_init <%u %u %u %llu>\n",
 		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
 
+	if (sdebug_lun_eh)
+		return scsi_device_setup_eh(sdp, sdebug_lun_eh_fallback);
+
 	return 0;
 }
 
@@ -5953,6 +5958,9 @@ static void scsi_debug_sdev_destroy(struct scsi_device *sdp)
 	/* make this slot available for re-use */
 	devip->used = false;
 	sdp->hostdata = NULL;
+
+	if (sdebug_lun_eh)
+		scsi_device_clear_eh(sdp);
 }
 
 /* Returns true if we require the queued memory to be freed by the caller. */
@@ -6644,6 +6652,8 @@ module_param_named(zone_max_open, sdeb_zbc_max_open, int, S_IRUGO);
 module_param_named(zone_nr_conv, sdeb_zbc_nr_conv, int, S_IRUGO);
 module_param_named(zone_size_mb, sdeb_zbc_zone_size_mb, int, S_IRUGO);
 module_param_named(allow_restart, sdebug_allow_restart, bool, S_IRUGO | S_IWUSR);
+module_param_named(lun_eh, sdebug_lun_eh, bool, S_IRUGO);
+module_param_named(lun_eh_fallback, sdebug_lun_eh_fallback, bool, S_IRUGO);
 
 MODULE_AUTHOR("Eric Youngdale + Douglas Gilbert");
 MODULE_DESCRIPTION("SCSI debug adapter driver");
@@ -6723,6 +6733,8 @@ MODULE_PARM_DESC(zone_max_open, "Maximum number of open zones; [0] for no limit
 MODULE_PARM_DESC(zone_nr_conv, "Number of conventional zones (def=1)");
 MODULE_PARM_DESC(zone_size_mb, "Zone size in MiB (def=auto)");
 MODULE_PARM_DESC(allow_restart, "Set scsi_device's allow_restart flag(def=0)");
+MODULE_PARM_DESC(lun_eh, "LUN based error handle (def=0)");
+MODULE_PARM_DESC(lun_eh_fallback, "Fallback to further recovery if LUN recovery failed (def=0)");
 
 #define SDEBUG_INFO_LEN 256
 static char sdebug_info[SDEBUG_INFO_LEN];
-- 
2.33.0