Commit ef4f7e4b authored by Dmitry Bogdanov's avatar Dmitry Bogdanov Committed by Martin K. Petersen
Browse files

scsi: target: core: De-RCU of se_lun and se_lun acl 

se_lun and se_lun_acl are immutable pointers of struct se_dev_entry.
Remove RCU usage for access to those pointers.

Link: https://lore.kernel.org/r/20220727214125.19647-3-d.bogdanov@yadro.com


Reviewed-by: default avatarMike Christie <michael.christie@oracle.com>
Signed-off-by: default avatarDmitry Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent dd0a66ad

drivers/target/target_core_alua.c

+1 −2
Original line number Diff line number Diff line
@@ -934,8 +934,7 @@ static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp) 


		spin_lock(&lun->lun_deve_lock);

		list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {

			lacl = rcu_dereference_check(se_deve->se_lun_acl,

					lockdep_is_held(&lun->lun_deve_lock));

			lacl = se_deve->se_lun_acl;



			/*

			 * spc4r37 p.242:

drivers/target/target_core_device.c

+11 −18
Original line number Diff line number Diff line
@@ -75,7 +75,7 @@ transport_lookup_cmd_lun(struct se_cmd *se_cmd) 
			return TCM_WRITE_PROTECTED;

		}



		se_lun = rcu_dereference(deve->se_lun);

		se_lun = deve->se_lun;



		if (!percpu_ref_tryget_live(&se_lun->lun_ref)) {

			se_lun = NULL;
@@ -152,7 +152,7 @@ int transport_lookup_tmr_lun(struct se_cmd *se_cmd) 
	rcu_read_lock();

	deve = target_nacl_find_deve(nacl, se_cmd->orig_fe_lun);

	if (deve) {

		se_lun = rcu_dereference(deve->se_lun);

		se_lun = deve->se_lun;



		if (!percpu_ref_tryget_live(&se_lun->lun_ref)) {

			se_lun = NULL;
@@ -216,7 +216,7 @@ struct se_dev_entry *core_get_se_deve_from_rtpi( 


	rcu_read_lock();

	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {

		lun = rcu_dereference(deve->se_lun);

		lun = deve->se_lun;

		if (!lun) {

			pr_err("%s device entries device pointer is"

				" NULL, but Initiator has access.\n",
@@ -243,11 +243,8 @@ void core_free_device_list_for_node( 
	struct se_dev_entry *deve;



	mutex_lock(&nacl->lun_entry_mutex);

	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {

		struct se_lun *lun = rcu_dereference_check(deve->se_lun,

					lockdep_is_held(&nacl->lun_entry_mutex));

		core_disable_device_list_for_node(lun, deve, nacl, tpg);

	}

	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link)

		core_disable_device_list_for_node(deve->se_lun, deve, nacl, tpg);

	mutex_unlock(&nacl->lun_entry_mutex);

}
@@ -334,8 +331,7 @@ int core_enable_device_list_for_node( 
	mutex_lock(&nacl->lun_entry_mutex);

	orig = target_nacl_find_deve(nacl, mapped_lun);

	if (orig && orig->se_lun) {

		struct se_lun *orig_lun = rcu_dereference_check(orig->se_lun,

					lockdep_is_held(&nacl->lun_entry_mutex));

		struct se_lun *orig_lun = orig->se_lun;



		if (orig_lun != lun) {

			pr_err("Existing orig->se_lun doesn't match new lun"
@@ -355,8 +351,8 @@ int core_enable_device_list_for_node( 
			return -EINVAL;

		}



		rcu_assign_pointer(new->se_lun, lun);

		rcu_assign_pointer(new->se_lun_acl, lun_acl);

		new->se_lun = lun;

		new->se_lun_acl = lun_acl;

		hlist_del_rcu(&orig->link);

		hlist_add_head_rcu(&new->link, &nacl->lun_entry_hlist);

		mutex_unlock(&nacl->lun_entry_mutex);
@@ -374,8 +370,8 @@ int core_enable_device_list_for_node( 
		return 0;

	}



	rcu_assign_pointer(new->se_lun, lun);

	rcu_assign_pointer(new->se_lun_acl, lun_acl);

	new->se_lun = lun;

	new->se_lun_acl = lun_acl;

	hlist_add_head_rcu(&new->link, &nacl->lun_entry_hlist);

	mutex_unlock(&nacl->lun_entry_mutex);
@@ -454,10 +450,7 @@ void core_clear_lun_from_tpg(struct se_lun *lun, struct se_portal_group *tpg) 


		mutex_lock(&nacl->lun_entry_mutex);

		hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {

			struct se_lun *tmp_lun = rcu_dereference_check(deve->se_lun,

					lockdep_is_held(&nacl->lun_entry_mutex));



			if (lun != tmp_lun)

			if (lun != deve->se_lun)

				continue;



			core_disable_device_list_for_node(lun, deve, nacl, tpg);

drivers/target/target_core_pr.c

+8 −20
Original line number Diff line number Diff line
@@ -739,8 +739,7 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( 
			if (!deve_tmp->se_lun_acl)

				continue;



			lacl_tmp = rcu_dereference_check(deve_tmp->se_lun_acl,

						lockdep_is_held(&lun_tmp->lun_deve_lock));

			lacl_tmp = deve_tmp->se_lun_acl;

			nacl_tmp = lacl_tmp->se_lun_nacl;

			/*

			 * Skip the matching struct se_node_acl that is allocated
@@ -784,8 +783,7 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( 
			 * the original *pr_reg is processed in

			 * __core_scsi3_add_registration()

			 */

			dest_lun = rcu_dereference_check(deve_tmp->se_lun,

				kref_read(&deve_tmp->pr_kref) != 0);

			dest_lun = deve_tmp->se_lun;



			pr_reg_atp = __core_scsi3_do_alloc_registration(dev,

						nacl_tmp, dest_lun, deve_tmp,
@@ -1437,34 +1435,26 @@ static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl) 


static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)

{

	struct se_lun_acl *lun_acl;



	/*

	 * For nacl->dynamic_node_acl=1

	 */

	lun_acl = rcu_dereference_check(se_deve->se_lun_acl,

				kref_read(&se_deve->pr_kref) != 0);

	if (!lun_acl)

	if (!se_deve->se_lun_acl)

		return 0;



	return target_depend_item(&lun_acl->se_lun_group.cg_item);

	return target_depend_item(&se_deve->se_lun_acl->se_lun_group.cg_item);

}



static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)

{

	struct se_lun_acl *lun_acl;



	/*

	 * For nacl->dynamic_node_acl=1

	 */

	lun_acl = rcu_dereference_check(se_deve->se_lun_acl,

				kref_read(&se_deve->pr_kref) != 0);

	if (!lun_acl) {

	if (!se_deve->se_lun_acl) {

		kref_put(&se_deve->pr_kref, target_pr_kref_release);

		return;

	}



	target_undepend_item(&lun_acl->se_lun_group.cg_item);

	target_undepend_item(&se_deve->se_lun_acl->se_lun_group.cg_item);

	kref_put(&se_deve->pr_kref, target_pr_kref_release);

}
@@ -1751,8 +1741,7 @@ core_scsi3_decode_spec_i_port( 
		 * and then call __core_scsi3_add_registration() in the

		 * 2nd loop which will never fail.

		 */

		dest_lun = rcu_dereference_check(dest_se_deve->se_lun,

				kref_read(&dest_se_deve->pr_kref) != 0);

		dest_lun = dest_se_deve->se_lun;



		dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,

					dest_node_acl, dest_lun, dest_se_deve,
@@ -3446,8 +3435,7 @@ core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key, 
	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,

					iport_ptr);

	if (!dest_pr_reg) {

		struct se_lun *dest_lun = rcu_dereference_check(dest_se_deve->se_lun,

				kref_read(&dest_se_deve->pr_kref) != 0);

		struct se_lun *dest_lun = dest_se_deve->se_lun;



		spin_unlock(&dev->dev_reservation_lock);

		if (core_scsi3_alloc_registration(cmd->se_dev, dest_node_acl,

drivers/target/target_core_stat.c

+4 −6
Original line number Diff line number Diff line
@@ -877,7 +877,6 @@ static ssize_t target_stat_auth_dev_show(struct config_item *item, 
	struct se_lun_acl *lacl = auth_to_lacl(item);

	struct se_node_acl *nacl = lacl->se_lun_nacl;

	struct se_dev_entry *deve;

	struct se_lun *lun;

	ssize_t ret;



	rcu_read_lock();
@@ -886,9 +885,9 @@ static ssize_t target_stat_auth_dev_show(struct config_item *item, 
		rcu_read_unlock();

		return -ENODEV;

	}

	lun = rcu_dereference(deve->se_lun);



	/* scsiDeviceIndex */

	ret = snprintf(page, PAGE_SIZE, "%u\n", lun->lun_index);

	ret = snprintf(page, PAGE_SIZE, "%u\n", deve->se_lun->lun_index);

	rcu_read_unlock();

	return ret;

}
@@ -1217,7 +1216,6 @@ static ssize_t target_stat_iport_dev_show(struct config_item *item, 
	struct se_lun_acl *lacl = iport_to_lacl(item);

	struct se_node_acl *nacl = lacl->se_lun_nacl;

	struct se_dev_entry *deve;

	struct se_lun *lun;

	ssize_t ret;



	rcu_read_lock();
@@ -1226,9 +1224,9 @@ static ssize_t target_stat_iport_dev_show(struct config_item *item, 
		rcu_read_unlock();

		return -ENODEV;

	}

	lun = rcu_dereference(deve->se_lun);



	/* scsiDeviceIndex */

	ret = snprintf(page, PAGE_SIZE, "%u\n", lun->lun_index);

	ret = snprintf(page, PAGE_SIZE, "%u\n", deve->se_lun->lun_index);

	rcu_read_unlock();

	return ret;

}

drivers/target/target_core_xcopy.c

+1 −1
Original line number Diff line number Diff line
@@ -88,7 +88,7 @@ static int target_xcopy_locate_se_dev_e4(struct se_session *sess, 
		struct se_device *this_dev;

		int rc;



		this_lun = rcu_dereference(deve->se_lun);

		this_lun = deve->se_lun;

		this_dev = rcu_dereference_raw(this_lun->lun_se_dev);



		rc = target_xcopy_locate_se_dev_e4_iter(this_dev, dev_wwn);