target: fix return code of core_tpg_.*_lun

- core_tpg_pre_addlun()
  returns always ERR_PTR() or the pointer, never NULL. The additional
  check for NULL in core_dev_add_lun() is not required.

- core_tpg_pre_dellun()
  returns always ERR_PTR() or the pointer, never NULL. The check for NULL
  in core_dev_del_lun() is wrong. The third argument (int *) is never
  used, remove it.

- core_dev_add_lun()
  returns always NULL or the pointer, never ERR_PTR. The check for
  IS_ERR() is not required.

(nab: Convert core_dev_add_lun() use err.h macros for failure
handling to be consistent with the rest of target_core_fabric_configfs.c
callers)
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_device.c

@@ -1295,24 +1295,26 @@ struct se_lun *core_dev_add_lun(
 {
 	struct se_lun *lun_p;
 	u32 lun_access = 0;
+	int rc;
 
 	if (atomic_read(&dev->dev_access_obj.obj_access_count) != 0) {
 		pr_err("Unable to export struct se_device while dev_access_obj: %d\n",
 			atomic_read(&dev->dev_access_obj.obj_access_count));
-		return NULL;
+		return ERR_PTR(-EACCES);
 	}
 
 	lun_p = core_tpg_pre_addlun(tpg, lun);
-	if ((IS_ERR(lun_p)) || !lun_p)
-		return NULL;
+	if (IS_ERR(lun_p))
+		return lun_p;
 
 	if (dev->dev_flags & DF_READ_ONLY)
 		lun_access = TRANSPORT_LUNFLAGS_READ_ONLY;
 	else
 		lun_access = TRANSPORT_LUNFLAGS_READ_WRITE;
 
-	if (core_tpg_post_addlun(tpg, lun_p, lun_access, dev) < 0)
-		return NULL;
+	rc = core_tpg_post_addlun(tpg, lun_p, lun_access, dev);
+	if (rc < 0)
+		return ERR_PTR(rc);
 
 	pr_debug("%s_TPG[%u]_LUN[%u] - Activated %s Logical Unit from"
 		" CORE HBA: %u\n", tpg->se_tpg_tfo->get_fabric_name(),
@@ -1349,11 +1351,10 @@ int core_dev_del_lun(
 	u32 unpacked_lun)
 {
 	struct se_lun *lun;
-	int ret = 0;
 
-	lun = core_tpg_pre_dellun(tpg, unpacked_lun, &ret);
-	if (!lun)
-		return ret;
+	lun = core_tpg_pre_dellun(tpg, unpacked_lun);
+	if (IS_ERR(lun))
+		return PTR_ERR(lun);
 
 	core_tpg_post_dellun(tpg, lun);
 

drivers/target/target_core_fabric_configfs.c

@@ -766,9 +766,9 @@ static int target_fabric_port_link(
 
 	lun_p = core_dev_add_lun(se_tpg, dev->se_hba, dev,
 				lun->unpacked_lun);
-	if (IS_ERR(lun_p) || !lun_p) {
+	if (IS_ERR(lun_p)) {
 		pr_err("core_dev_add_lun() failed\n");
-		ret = -EINVAL;
+		ret = PTR_ERR(lun_p);
 		goto out;
 	}
 

drivers/target/target_core_internal.h

@@ -90,7 +90,7 @@ void	core_tpg_wait_for_nacl_pr_ref(struct se_node_acl *);
 struct se_lun *core_tpg_pre_addlun(struct se_portal_group *, u32);
 int	core_tpg_post_addlun(struct se_portal_group *, struct se_lun *,
 		u32, void *);
-struct se_lun *core_tpg_pre_dellun(struct se_portal_group *, u32, int *);
+struct se_lun *core_tpg_pre_dellun(struct se_portal_group *, u32 unpacked_lun);
 int	core_tpg_post_dellun(struct se_portal_group *, struct se_lun *);
 
 /* target_core_transport.c */

drivers/target/target_core_tpg.c

@@ -807,8 +807,7 @@ static void core_tpg_shutdown_lun(
 
 struct se_lun *core_tpg_pre_dellun(
 	struct se_portal_group *tpg,
-	u32 unpacked_lun,
-	int *ret)
+	u32 unpacked_lun)
 {
 	struct se_lun *lun;