Commit 6bb82612 authored by Nicholas Bellinger's avatar Nicholas Bellinger
Browse files

target: Convert se_portal_group->tpg_lun_list[] to RCU hlist 



This patch converts the fixed size se_portal_group->tpg_lun_list[]
to use modern RCU with hlist_head in order to support an arbitary
number of se_lun ports per target endpoint.

It includes dropping core_tpg_alloc_lun() from core_dev_add_lun(),
and calling it directly from target_fabric_make_lun() to allocate
a new se_lun.  And add a new target_fabric_port_release() configfs
item callback to invoke kfree_rcu() to release memory during
se_lun->lun_group shutdown.

Also now that se_node_acl->lun_entry_hlist is using RCU, convert
existing tpg_lun_lock to struct mutex so core_tpg_add_node_to_devs()
can perform RCU updater logic without releasing ->tpg_lun_mutex.

Also, drop core_tpg_clear_object_luns() and it's single consumer
in iscsi-target, which is duplicating TPG LUN shutdown logic and
is current code results in a NOP.

Finally, sbp-target and xen-scsiback fabric driver conversions are
included, which are required due to the non-standard way they use
->tpg_lun_hlist.

Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Chris Boot <bootc@bootc.net>
Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
parent 9fcb57f3

drivers/target/iscsi/iscsi_target_tpg.c

+0 −2
Original line number Diff line number Diff line
@@ -278,8 +278,6 @@ int iscsit_tpg_del_portal_group( 
		return -EPERM;

	}



	core_tpg_clear_object_luns(&tpg->tpg_se_tpg);



	if (tpg->param_list) {

		iscsi_release_param_list(tpg->param_list);

		tpg->param_list = NULL;

drivers/target/sbp/sbp_target.c

+42 −55
Original line number Diff line number Diff line
@@ -108,13 +108,13 @@ static struct sbp_session *sbp_session_find_by_guid( 
}



static struct sbp_login_descriptor *sbp_login_find_by_lun(

		struct sbp_session *session, struct se_lun *lun)

		struct sbp_session *session, u32 unpacked_lun)

{

	struct sbp_login_descriptor *login, *found = NULL;



	spin_lock_bh(&session->lock);

	list_for_each_entry(login, &session->login_list, link) {

		if (login->lun == lun)

		if (login->login_lun == unpacked_lun)

			found = login;

	}

	spin_unlock_bh(&session->lock);
@@ -124,7 +124,7 @@ static struct sbp_login_descriptor *sbp_login_find_by_lun( 


static int sbp_login_count_all_by_lun(

		struct sbp_tpg *tpg,

		struct se_lun *lun,

		u32 unpacked_lun,

		int exclusive)

{

	struct se_session *se_sess;
@@ -138,7 +138,7 @@ static int sbp_login_count_all_by_lun( 


		spin_lock_bh(&sess->lock);

		list_for_each_entry(login, &sess->login_list, link) {

			if (login->lun != lun)

			if (login->login_lun != unpacked_lun)

				continue;



			if (!exclusive || login->exclusive)
@@ -174,23 +174,23 @@ static struct sbp_login_descriptor *sbp_login_find_by_id( 
	return found;

}



static struct se_lun *sbp_get_lun_from_tpg(struct sbp_tpg *tpg, int lun)

static u32 sbp_get_lun_from_tpg(struct sbp_tpg *tpg, u32 login_lun, int *err)

{

	struct se_portal_group *se_tpg = &tpg->se_tpg;

	struct se_lun *se_lun;



	if (lun >= TRANSPORT_MAX_LUNS_PER_TPG)

		return ERR_PTR(-EINVAL);



	spin_lock(&se_tpg->tpg_lun_lock);

	se_lun = se_tpg->tpg_lun_list[lun];



	if (se_lun->lun_status != TRANSPORT_LUN_STATUS_ACTIVE)

		se_lun = ERR_PTR(-ENODEV);



	spin_unlock(&se_tpg->tpg_lun_lock);

	rcu_read_lock();

	hlist_for_each_entry_rcu(se_lun, &se_tpg->tpg_lun_hlist, link) {

		if (se_lun->unpacked_lun == login_lun) {

			rcu_read_unlock();

			*err = 0;

			return login_lun;

		}

	}

	rcu_read_unlock();



	return se_lun;

	*err = -ENODEV;

	return login_lun;

}



static struct sbp_session *sbp_session_create(
@@ -294,17 +294,16 @@ static void sbp_management_request_login( 
{

	struct sbp_tport *tport = agent->tport;

	struct sbp_tpg *tpg = tport->tpg;

	struct se_lun *se_lun;

	int ret;

	u64 guid;

	struct sbp_session *sess;

	struct sbp_login_descriptor *login;

	struct sbp_login_response_block *response;

	int login_response_len;

	u64 guid;

	u32 unpacked_lun;

	int login_response_len, ret;



	se_lun = sbp_get_lun_from_tpg(tpg,

			LOGIN_ORB_LUN(be32_to_cpu(req->orb.misc)));

	if (IS_ERR(se_lun)) {

	unpacked_lun = sbp_get_lun_from_tpg(tpg,

			LOGIN_ORB_LUN(be32_to_cpu(req->orb.misc)), &ret);

	if (ret) {

		pr_notice("login to unknown LUN: %d\n",

			LOGIN_ORB_LUN(be32_to_cpu(req->orb.misc)));
@@ -325,11 +324,11 @@ static void sbp_management_request_login( 
	}



	pr_notice("mgt_agent LOGIN to LUN %d from %016llx\n",

		se_lun->unpacked_lun, guid);

		unpacked_lun, guid);



	sess = sbp_session_find_by_guid(tpg, guid);

	if (sess) {

		login = sbp_login_find_by_lun(sess, se_lun);

		login = sbp_login_find_by_lun(sess, unpacked_lun);

		if (login) {

			pr_notice("initiator already logged-in\n");
@@ -357,7 +356,7 @@ static void sbp_management_request_login( 
	 * reject with access_denied if any logins present

	 */

	if (LOGIN_ORB_EXCLUSIVE(be32_to_cpu(req->orb.misc)) &&

			sbp_login_count_all_by_lun(tpg, se_lun, 0)) {

			sbp_login_count_all_by_lun(tpg, unpacked_lun, 0)) {

		pr_warn("refusing exclusive login with other active logins\n");



		req->status.status = cpu_to_be32(
@@ -370,7 +369,7 @@ static void sbp_management_request_login( 
	 * check exclusive bit in any existing login descriptor

	 * reject with access_denied if any exclusive logins present

	 */

	if (sbp_login_count_all_by_lun(tpg, se_lun, 1)) {

	if (sbp_login_count_all_by_lun(tpg, unpacked_lun, 1)) {

		pr_warn("refusing login while another exclusive login present\n");



		req->status.status = cpu_to_be32(
@@ -383,7 +382,7 @@ static void sbp_management_request_login( 
	 * check we haven't exceeded the number of allowed logins

	 * reject with resources_unavailable if we have

	 */

	if (sbp_login_count_all_by_lun(tpg, se_lun, 0) >=

	if (sbp_login_count_all_by_lun(tpg, unpacked_lun, 0) >=

			tport->max_logins_per_lun) {

		pr_warn("max number of logins reached\n");
@@ -439,7 +438,7 @@ static void sbp_management_request_login( 
	}



	login->sess = sess;

	login->lun = se_lun;

	login->login_lun = unpacked_lun;

	login->status_fifo_addr = sbp2_pointer_to_addr(&req->orb.status_fifo);

	login->exclusive = LOGIN_ORB_EXCLUSIVE(be32_to_cpu(req->orb.misc));

	login->login_id = atomic_inc_return(&login_id);
@@ -601,7 +600,7 @@ static void sbp_management_request_logout( 
	}



	pr_info("mgt_agent LOGOUT from LUN %d session %d\n",

		login->lun->unpacked_lun, login->login_id);

		login->login_lun, login->login_id);



	if (req->node_addr != login->sess->node_id) {

		pr_warn("logout from different node ID\n");
@@ -1227,7 +1226,7 @@ static void sbp_handle_command(struct sbp_target_request *req) 
		goto err;

	}



	unpacked_lun = req->login->lun->unpacked_lun;

	unpacked_lun = req->login->login_lun;

	sbp_calc_data_length_direction(req, &data_length, &data_dir);



	pr_debug("sbp_handle_command ORB:0x%llx unpacked_lun:%d data_len:%d data_dir:%d\n",
@@ -1826,25 +1825,21 @@ static int sbp_check_stop_free(struct se_cmd *se_cmd) 


static int sbp_count_se_tpg_luns(struct se_portal_group *tpg)

{

	int i, count = 0;



	spin_lock(&tpg->tpg_lun_lock);

	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {

		struct se_lun *se_lun = tpg->tpg_lun_list[i];



		if (se_lun->lun_status == TRANSPORT_LUN_STATUS_FREE)

			continue;

	struct se_lun *lun;

	int count = 0;



	rcu_read_lock();

	hlist_for_each_entry_rcu(lun, &tpg->tpg_lun_hlist, link)

		count++;

	}

	spin_unlock(&tpg->tpg_lun_lock);

	rcu_read_unlock();



	return count;

}



static int sbp_update_unit_directory(struct sbp_tport *tport)

{

	int num_luns, num_entries, idx = 0, mgt_agt_addr, ret, i;

	struct se_lun *lun;

	int num_luns, num_entries, idx = 0, mgt_agt_addr, ret;

	u32 *data;



	if (tport->unit_directory.data) {
@@ -1906,28 +1901,20 @@ static int sbp_update_unit_directory(struct sbp_tport *tport) 
	/* unit unique ID (leaf is just after LUNs) */

	data[idx++] = 0x8d000000 | (num_luns + 1);



	spin_lock(&tport->tpg->se_tpg.tpg_lun_lock);

	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {

		struct se_lun *se_lun = tport->tpg->se_tpg.tpg_lun_list[i];

	rcu_read_lock();

	hlist_for_each_entry_rcu(lun, &tport->tpg->se_tpg.tpg_lun_hlist, link) {

		struct se_device *dev;

		int type;



		if (se_lun->lun_status == TRANSPORT_LUN_STATUS_FREE)

			continue;



		spin_unlock(&tport->tpg->se_tpg.tpg_lun_lock);



		dev = se_lun->lun_se_dev;

		dev = lun->lun_se_dev;

		type = dev->transport->get_device_type(dev);



		/* logical_unit_number */

		data[idx++] = 0x14000000 |

			((type << 16) & 0x1f0000) |

			(se_lun->unpacked_lun & 0xffff);



		spin_lock(&tport->tpg->se_tpg.tpg_lun_lock);

			(lun->unpacked_lun & 0xffff);

	}

	spin_unlock(&tport->tpg->se_tpg.tpg_lun_lock);

	rcu_read_unlock();



	/* unit unique ID leaf */

	data[idx++] = 2 << 16;

drivers/target/sbp/sbp_target.h

+1 −1
Original line number Diff line number Diff line
@@ -125,7 +125,7 @@ struct sbp_login_descriptor { 
	struct sbp_session *sess;

	struct list_head link;



	struct se_lun *lun;

	u32 login_lun;



	u64 status_fifo_addr;

	int exclusive;

drivers/target/target_core_device.c

+7 −85
Original line number Diff line number Diff line
@@ -1172,22 +1172,17 @@ int se_dev_set_block_size(struct se_device *dev, u32 block_size) 
}

EXPORT_SYMBOL(se_dev_set_block_size);



struct se_lun *core_dev_add_lun(

int core_dev_add_lun(

	struct se_portal_group *tpg,

	struct se_device *dev,

	u32 unpacked_lun)

	struct se_lun *lun)

{

	struct se_lun *lun;

	int rc;



	lun = core_tpg_alloc_lun(tpg, unpacked_lun);

	if (IS_ERR(lun))

		return lun;



	rc = core_tpg_add_lun(tpg, lun,

				TRANSPORT_LUNFLAGS_READ_WRITE, dev);

	if (rc < 0)

		return ERR_PTR(rc);

		return rc;



	pr_debug("%s_TPG[%u]_LUN[%u] - Activated %s Logical Unit from"

		" CORE HBA: %u\n", tpg->se_tpg_tfo->get_fabric_name(),
@@ -1212,7 +1207,7 @@ struct se_lun *core_dev_add_lun( 
		spin_unlock_irq(&tpg->acl_node_lock);

	}



	return lun;

	return 0;

}



/*      core_dev_del_lun():
@@ -1231,68 +1226,6 @@ void core_dev_del_lun( 
	core_tpg_remove_lun(tpg, lun);

}



struct se_lun *core_get_lun_from_tpg(struct se_portal_group *tpg, u32 unpacked_lun)

{

	struct se_lun *lun;



	spin_lock(&tpg->tpg_lun_lock);

	if (unpacked_lun > (TRANSPORT_MAX_LUNS_PER_TPG-1)) {

		pr_err("%s LUN: %u exceeds TRANSPORT_MAX_LUNS"

			"_PER_TPG-1: %u for Target Portal Group: %hu\n",

			tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,

			TRANSPORT_MAX_LUNS_PER_TPG-1,

			tpg->se_tpg_tfo->tpg_get_tag(tpg));

		spin_unlock(&tpg->tpg_lun_lock);

		return NULL;

	}

	lun = tpg->tpg_lun_list[unpacked_lun];



	if (lun->lun_status != TRANSPORT_LUN_STATUS_FREE) {

		pr_err("%s Logical Unit Number: %u is not free on"

			" Target Portal Group: %hu, ignoring request.\n",

			tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,

			tpg->se_tpg_tfo->tpg_get_tag(tpg));

		spin_unlock(&tpg->tpg_lun_lock);

		return NULL;

	}

	spin_unlock(&tpg->tpg_lun_lock);



	return lun;

}



/*      core_dev_get_lun():

 *

 *

 */

static struct se_lun *core_dev_get_lun(struct se_portal_group *tpg, u32 unpacked_lun)

{

	struct se_lun *lun;



	spin_lock(&tpg->tpg_lun_lock);

	if (unpacked_lun > (TRANSPORT_MAX_LUNS_PER_TPG-1)) {

		pr_err("%s LUN: %u exceeds TRANSPORT_MAX_LUNS_PER"

			"_TPG-1: %u for Target Portal Group: %hu\n",

			tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,

			TRANSPORT_MAX_LUNS_PER_TPG-1,

			tpg->se_tpg_tfo->tpg_get_tag(tpg));

		spin_unlock(&tpg->tpg_lun_lock);

		return NULL;

	}

	lun = tpg->tpg_lun_list[unpacked_lun];



	if (lun->lun_status != TRANSPORT_LUN_STATUS_ACTIVE) {

		pr_err("%s Logical Unit Number: %u is not active on"

			" Target Portal Group: %hu, ignoring request.\n",

			tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,

			tpg->se_tpg_tfo->tpg_get_tag(tpg));

		spin_unlock(&tpg->tpg_lun_lock);

		return NULL;

	}

	spin_unlock(&tpg->tpg_lun_lock);



	return lun;

}



struct se_lun_acl *core_dev_init_initiator_node_lun_acl(

	struct se_portal_group *tpg,

	struct se_node_acl *nacl,
@@ -1326,22 +1259,11 @@ struct se_lun_acl *core_dev_init_initiator_node_lun_acl( 
int core_dev_add_initiator_node_lun_acl(

	struct se_portal_group *tpg,

	struct se_lun_acl *lacl,

	u32 unpacked_lun,

	struct se_lun *lun,

	u32 lun_access)

{

	struct se_lun *lun;

	struct se_node_acl *nacl;

	struct se_node_acl *nacl = lacl->se_lun_nacl;



	lun = core_dev_get_lun(tpg, unpacked_lun);

	if (!lun) {

		pr_err("%s Logical Unit Number: %u is not active on"

			" Target Portal Group: %hu, ignoring request.\n",

			tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,

			tpg->se_tpg_tfo->tpg_get_tag(tpg));

		return -EINVAL;

	}



	nacl = lacl->se_lun_nacl;

	if (!nacl)

		return -EINVAL;
@@ -1362,7 +1284,7 @@ int core_dev_add_initiator_node_lun_acl( 


	pr_debug("%s_TPG[%hu]_LUN[%u->%u] - Added %s ACL for "

		" InitiatorNode: %s\n", tpg->se_tpg_tfo->get_fabric_name(),

		tpg->se_tpg_tfo->tpg_get_tag(tpg), unpacked_lun, lacl->mapped_lun,

		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun, lacl->mapped_lun,

		(lun_access & TRANSPORT_LUNFLAGS_READ_WRITE) ? "RW" : "RO",

		lacl->initiatorname);

	/*

drivers/target/target_core_fabric_configfs.c

+20 −14
Original line number Diff line number Diff line
@@ -81,7 +81,7 @@ static int target_fabric_mappedlun_link( 
			struct se_lun_acl, se_lun_group);

	struct se_portal_group *se_tpg;

	struct config_item *nacl_ci, *tpg_ci, *tpg_ci_s, *wwn_ci, *wwn_ci_s;

	int ret = 0, lun_access;

	int lun_access;



	if (lun->lun_link_magic != SE_LUN_LINK_MAGIC) {

		pr_err("Bad lun->lun_link_magic, not a valid lun_ci pointer:"
@@ -137,12 +137,9 @@ static int target_fabric_mappedlun_link( 
	 * Determine the actual mapped LUN value user wants..

	 *

	 * This value is what the SCSI Initiator actually sees the

	 * iscsi/$IQN/$TPGT/lun/lun_* as on their SCSI Initiator Ports.

	 * $FABRIC/$WWPN/$TPGT/lun/lun_* as on their SCSI Initiator Ports.

	 */

	ret = core_dev_add_initiator_node_lun_acl(se_tpg, lacl,

			lun->unpacked_lun, lun_access);



	return (ret < 0) ? -EINVAL : 0;

	return core_dev_add_initiator_node_lun_acl(se_tpg, lacl, lun, lun_access);

}



static int target_fabric_mappedlun_unlink(
@@ -761,7 +758,6 @@ static int target_fabric_port_link( 
	struct config_item *tpg_ci;

	struct se_lun *lun = container_of(to_config_group(lun_ci),

				struct se_lun, lun_group);

	struct se_lun *lun_p;

	struct se_portal_group *se_tpg;

	struct se_device *dev =

		container_of(to_config_group(se_dev_ci), struct se_device, dev_group);
@@ -789,10 +785,9 @@ static int target_fabric_port_link( 
		return -EEXIST;

	}



	lun_p = core_dev_add_lun(se_tpg, dev, lun->unpacked_lun);

	if (IS_ERR(lun_p)) {

		pr_err("core_dev_add_lun() failed\n");

		ret = PTR_ERR(lun_p);

	ret = core_dev_add_lun(se_tpg, dev, lun);

	if (ret) {

		pr_err("core_dev_add_lun() failed: %d\n", ret);

		goto out;

	}
@@ -832,9 +827,18 @@ static int target_fabric_port_unlink( 
	return 0;

}



static void target_fabric_port_release(struct config_item *item)

{

	struct se_lun *lun = container_of(to_config_group(item),

					  struct se_lun, lun_group);



	kfree_rcu(lun, rcu_head);

}



static struct configfs_item_operations target_fabric_port_item_ops = {

	.show_attribute		= target_fabric_port_attr_show,

	.store_attribute	= target_fabric_port_attr_store,

	.release		= target_fabric_port_release,

	.allow_link		= target_fabric_port_link,

	.drop_link		= target_fabric_port_unlink,

};
@@ -893,15 +897,16 @@ static struct config_group *target_fabric_make_lun( 
	if (unpacked_lun > UINT_MAX)

		return ERR_PTR(-EINVAL);



	lun = core_get_lun_from_tpg(se_tpg, unpacked_lun);

	if (!lun)

		return ERR_PTR(-EINVAL);

	lun = core_tpg_alloc_lun(se_tpg, unpacked_lun);

	if (IS_ERR(lun))

		return ERR_CAST(lun);



	lun_cg = &lun->lun_group;

	lun_cg->default_groups = kmalloc(sizeof(struct config_group *) * 2,

				GFP_KERNEL);

	if (!lun_cg->default_groups) {

		pr_err("Unable to allocate lun_cg->default_groups\n");

		kfree(lun);

		return ERR_PTR(-ENOMEM);

	}
@@ -918,6 +923,7 @@ static struct config_group *target_fabric_make_lun( 
	if (!port_stat_grp->default_groups) {

		pr_err("Unable to allocate port_stat_grp->default_groups\n");

		kfree(lun_cg->default_groups);

		kfree(lun);

		return ERR_PTR(-ENOMEM);

	}

	target_stat_setup_port_default_groups(lun);