[RFC PATCH v2 12/19] scsi: scsi_debug: Add param to control LUN bassed error handler

[Wenchao Hao <haowenchao2@huawei.com>]

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@huawei.com>
---
 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 f30399a75ec0..af3d43c9db6f 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -841,6 +841,8 @@ static bool have_dif_prot;
 static bool write_since_sync;
 static bool sdebug_statistics = DEF_STATISTICS;
 static bool sdebug_wp;
+static bool sdebug_lun_eh;
+static bool sdebug_lun_eh_fallback;
 /* Following enum: 0: no zbc, def; 1: host aware; 2: host managed */
 static enum blk_zoned_model sdeb_zbc_model = BLK_ZONED_NONE;
 static char *sdeb_zbc_model_s;
@@ -5437,6 +5439,9 @@ static int scsi_debug_slave_alloc(struct scsi_device *sdp)
 		pr_info("slave_alloc <%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;
 }
 
@@ -5491,6 +5496,9 @@ static void scsi_debug_slave_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. */
@@ -6167,6 +6175,8 @@ module_param_named(zone_cap_mb, sdeb_zbc_zone_cap_mb, int, S_IRUGO);
 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(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");
@@ -6239,6 +6249,8 @@ MODULE_PARM_DESC(zone_cap_mb, "Zone capacity in MiB (def=zone size)");
 MODULE_PARM_DESC(zone_max_open, "Maximum number of open zones; [0] for no limit (def=auto)");
 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(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];
-- 
2.35.3