[deliverable/linux.git] / drivers / target / tcm_fc / tfc_sess.c

/*
 * Copyright (c) 2010 Cisco Systems, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */

/* XXX TBD some includes may be extraneous */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/utsname.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kthread.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/configfs.h>
#include <linux/ctype.h>
#include <linux/hash.h>
#include <linux/rcupdate.h>
#include <linux/rculist.h>
#include <linux/kref.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/libfc.h>

#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <target/target_core_configfs.h>
#include <target/configfs_macros.h>

#include "tcm_fc.h"

static void ft_sess_delete_all(struct ft_tport *);

/*
 * Lookup or allocate target local port.
 * Caller holds ft_lport_lock.
 */
static struct ft_tport *ft_tport_get(struct fc_lport *lport)
{
	struct ft_tpg *tpg;
	struct ft_tport *tport;
	int i;

	tport = rcu_dereference_protected(lport->prov[FC_TYPE_FCP],
					  lockdep_is_held(&ft_lport_lock));
	if (tport && tport->tpg)
		return tport;

	tpg = ft_lport_find_tpg(lport);
	if (!tpg)
		return NULL;

	if (tport) {
		tport->tpg = tpg;
		tpg->tport = tport;
		return tport;
	}

	tport = kzalloc(sizeof(*tport), GFP_KERNEL);
	if (!tport)
		return NULL;

	tport->lport = lport;
	tport->tpg = tpg;
	tpg->tport = tport;
	for (i = 0; i < FT_SESS_HASH_SIZE; i++)
		INIT_HLIST_HEAD(&tport->hash[i]);

	rcu_assign_pointer(lport->prov[FC_TYPE_FCP], tport);
	return tport;
}

/*
 * Delete a target local port.
 * Caller holds ft_lport_lock.
 */
static void ft_tport_delete(struct ft_tport *tport)
{
	struct fc_lport *lport;
	struct ft_tpg *tpg;

	ft_sess_delete_all(tport);
	lport = tport->lport;
	BUG_ON(tport != lport->prov[FC_TYPE_FCP]);
	RCU_INIT_POINTER(lport->prov[FC_TYPE_FCP], NULL);

	tpg = tport->tpg;
	if (tpg) {
		tpg->tport = NULL;
		tport->tpg = NULL;
	}
	kfree_rcu(tport, rcu);
}

/*
 * Add local port.
 * Called thru fc_lport_iterate().
 */
void ft_lport_add(struct fc_lport *lport, void *arg)
{
	mutex_lock(&ft_lport_lock);
	ft_tport_get(lport);
	mutex_unlock(&ft_lport_lock);
}

/*
 * Delete local port.
 * Called thru fc_lport_iterate().
 */
void ft_lport_del(struct fc_lport *lport, void *arg)
{
	struct ft_tport *tport;

	mutex_lock(&ft_lport_lock);
	tport = lport->prov[FC_TYPE_FCP];
	if (tport)
		ft_tport_delete(tport);
	mutex_unlock(&ft_lport_lock);
}

/*
 * Notification of local port change from libfc.
 * Create or delete local port and associated tport.
 */
int ft_lport_notify(struct notifier_block *nb, unsigned long event, void *arg)
{
	struct fc_lport *lport = arg;

	switch (event) {
	case FC_LPORT_EV_ADD:
		ft_lport_add(lport, NULL);
		break;
	case FC_LPORT_EV_DEL:
		ft_lport_del(lport, NULL);
		break;
	}
	return NOTIFY_DONE;
}

/*
 * Hash function for FC_IDs.
 */
static u32 ft_sess_hash(u32 port_id)
{
	return hash_32(port_id, FT_SESS_HASH_BITS);
}

/*
 * Find session in local port.
 * Sessions and hash lists are RCU-protected.
 * A reference is taken which must be eventually freed.
 */
static struct ft_sess *ft_sess_get(struct fc_lport *lport, u32 port_id)
{
	struct ft_tport *tport;
	struct hlist_head *head;
	struct ft_sess *sess;

	rcu_read_lock();
	tport = rcu_dereference(lport->prov[FC_TYPE_FCP]);
	if (!tport)
		goto out;

	head = &tport->hash[ft_sess_hash(port_id)];
	hlist_for_each_entry_rcu(sess, head, hash) {
		if (sess->port_id == port_id) {
			kref_get(&sess->kref);
			rcu_read_unlock();
			pr_debug("port_id %x found %p\n", port_id, sess);
			return sess;
		}
	}
out:
	rcu_read_unlock();
	pr_debug("port_id %x not found\n", port_id);
	return NULL;
}

/*
 * Allocate session and enter it in the hash for the local port.
 * Caller holds ft_lport_lock.
 */
static struct ft_sess *ft_sess_create(struct ft_tport *tport, u32 port_id,
				      struct ft_node_acl *acl)
{
	struct ft_sess *sess;
	struct hlist_head *head;

	head = &tport->hash[ft_sess_hash(port_id)];
	hlist_for_each_entry_rcu(sess, head, hash)
		if (sess->port_id == port_id)
			return sess;

	sess = kzalloc(sizeof(*sess), GFP_KERNEL);
	if (!sess)
		return NULL;

	sess->se_sess = transport_init_session_tags(TCM_FC_DEFAULT_TAGS,
						    sizeof(struct ft_cmd),
						    TARGET_PROT_NORMAL);
	if (IS_ERR(sess->se_sess)) {
		kfree(sess);
		return NULL;
	}
	sess->se_sess->se_node_acl = &acl->se_node_acl;
	sess->tport = tport;
	sess->port_id = port_id;
	kref_init(&sess->kref);	/* ref for table entry */
	hlist_add_head_rcu(&sess->hash, head);
	tport->sess_count++;

	pr_debug("port_id %x sess %p\n", port_id, sess);

	transport_register_session(&tport->tpg->se_tpg, &acl->se_node_acl,
				   sess->se_sess, sess);
	return sess;
}

/*
 * Unhash the session.
 * Caller holds ft_lport_lock.
 */
static void ft_sess_unhash(struct ft_sess *sess)
{
	struct ft_tport *tport = sess->tport;

	hlist_del_rcu(&sess->hash);
	BUG_ON(!tport->sess_count);
	tport->sess_count--;
	sess->port_id = -1;
	sess->params = 0;
}

/*
 * Delete session from hash.
 * Caller holds ft_lport_lock.
 */
static struct ft_sess *ft_sess_delete(struct ft_tport *tport, u32 port_id)
{
	struct hlist_head *head;
	struct ft_sess *sess;

	head = &tport->hash[ft_sess_hash(port_id)];
	hlist_for_each_entry_rcu(sess, head, hash) {
		if (sess->port_id == port_id) {
			ft_sess_unhash(sess);
			return sess;
		}
	}
	return NULL;
}

/*
 * Delete all sessions from tport.
 * Caller holds ft_lport_lock.
 */
static void ft_sess_delete_all(struct ft_tport *tport)
{
	struct hlist_head *head;
	struct ft_sess *sess;

	for (head = tport->hash;
	     head < &tport->hash[FT_SESS_HASH_SIZE]; head++) {
		hlist_for_each_entry_rcu(sess, head, hash) {
			ft_sess_unhash(sess);
			transport_deregister_session_configfs(sess->se_sess);
			ft_sess_put(sess);	/* release from table */
		}
	}
}

/*
 * TCM ops for sessions.
 */

/*
 * Determine whether session is allowed to be shutdown in the current context.
 * Returns non-zero if the session should be shutdown.
 */
int ft_sess_shutdown(struct se_session *se_sess)
{
	struct ft_sess *sess = se_sess->fabric_sess_ptr;

	pr_debug("port_id %x\n", sess->port_id);
	return 1;
}

/*
 * Remove session and send PRLO.
 * This is called when the ACL is being deleted or queue depth is changing.
 */
void ft_sess_close(struct se_session *se_sess)
{
	struct ft_sess *sess = se_sess->fabric_sess_ptr;
	u32 port_id;

	mutex_lock(&ft_lport_lock);
	port_id = sess->port_id;
	if (port_id == -1) {
		mutex_unlock(&ft_lport_lock);
		return;
	}
	pr_debug("port_id %x\n", port_id);
	ft_sess_unhash(sess);
	mutex_unlock(&ft_lport_lock);
	transport_deregister_session_configfs(se_sess);
	ft_sess_put(sess);
	/* XXX Send LOGO or PRLO */
	synchronize_rcu();		/* let transport deregister happen */
}

u32 ft_sess_get_index(struct se_session *se_sess)
{
	struct ft_sess *sess = se_sess->fabric_sess_ptr;

	return sess->port_id;	/* XXX TBD probably not what is needed */
}

u32 ft_sess_get_port_name(struct se_session *se_sess,
			  unsigned char *buf, u32 len)
{
	struct ft_sess *sess = se_sess->fabric_sess_ptr;

	return ft_format_wwn(buf, len, sess->port_name);
}

/*
 * libfc ops involving sessions.
 */

static int ft_prli_locked(struct fc_rport_priv *rdata, u32 spp_len,
			  const struct fc_els_spp *rspp, struct fc_els_spp *spp)
{
	struct ft_tport *tport;
	struct ft_sess *sess;
	struct ft_node_acl *acl;
	u32 fcp_parm;

	tport = ft_tport_get(rdata->local_port);
	if (!tport)
		goto not_target;	/* not a target for this local port */

	acl = ft_acl_get(tport->tpg, rdata);
	if (!acl)
		goto not_target;	/* no target for this remote */

	if (!rspp)
		goto fill;

	if (rspp->spp_flags & (FC_SPP_OPA_VAL | FC_SPP_RPA_VAL))
		return FC_SPP_RESP_NO_PA;

	/*
	 * If both target and initiator bits are off, the SPP is invalid.
	 */
	fcp_parm = ntohl(rspp->spp_params);
	if (!(fcp_parm & (FCP_SPPF_INIT_FCN | FCP_SPPF_TARG_FCN)))
		return FC_SPP_RESP_INVL;

	/*
	 * Create session (image pair) only if requested by
	 * EST_IMG_PAIR flag and if the requestor is an initiator.
	 */
	if (rspp->spp_flags & FC_SPP_EST_IMG_PAIR) {
		spp->spp_flags |= FC_SPP_EST_IMG_PAIR;
		if (!(fcp_parm & FCP_SPPF_INIT_FCN))
			return FC_SPP_RESP_CONF;
		sess = ft_sess_create(tport, rdata->ids.port_id, acl);
		if (!sess)
			return FC_SPP_RESP_RES;
		if (!sess->params)
			rdata->prli_count++;
		sess->params = fcp_parm;
		sess->port_name = rdata->ids.port_name;
		sess->max_frame = rdata->maxframe_size;

		/* XXX TBD - clearing actions.  unit attn, see 4.10 */
	}

	/*
	 * OR in our service parameters with other provider (initiator), if any.
	 */
fill:
	fcp_parm = ntohl(spp->spp_params);
	fcp_parm &= ~FCP_SPPF_RETRY;
	spp->spp_params = htonl(fcp_parm | FCP_SPPF_TARG_FCN);
	return FC_SPP_RESP_ACK;

not_target:
	fcp_parm = ntohl(spp->spp_params);
	fcp_parm &= ~FCP_SPPF_TARG_FCN;
	spp->spp_params = htonl(fcp_parm);
	return 0;
}

/**
 * tcm_fcp_prli() - Handle incoming or outgoing PRLI for the FCP target
 * @rdata: remote port private
 * @spp_len: service parameter page length
 * @rspp: received service parameter page (NULL for outgoing PRLI)
 * @spp: response service parameter page
 *
 * Returns spp response code.
 */
static int ft_prli(struct fc_rport_priv *rdata, u32 spp_len,
		   const struct fc_els_spp *rspp, struct fc_els_spp *spp)
{
	int ret;

	mutex_lock(&ft_lport_lock);
	ret = ft_prli_locked(rdata, spp_len, rspp, spp);
	mutex_unlock(&ft_lport_lock);
	pr_debug("port_id %x flags %x ret %x\n",
	       rdata->ids.port_id, rspp ? rspp->spp_flags : 0, ret);
	return ret;
}

static void ft_sess_free(struct kref *kref)
{
	struct ft_sess *sess = container_of(kref, struct ft_sess, kref);

	transport_deregister_session(sess->se_sess);
	kfree_rcu(sess, rcu);
}

void ft_sess_put(struct ft_sess *sess)
{
	int sess_held = atomic_read(&sess->kref.refcount);

	BUG_ON(!sess_held);
	kref_put(&sess->kref, ft_sess_free);
}

static void ft_prlo(struct fc_rport_priv *rdata)
{
	struct ft_sess *sess;
	struct ft_tport *tport;

	mutex_lock(&ft_lport_lock);
	tport = rcu_dereference_protected(rdata->local_port->prov[FC_TYPE_FCP],
					  lockdep_is_held(&ft_lport_lock));

	if (!tport) {
		mutex_unlock(&ft_lport_lock);
		return;
	}
	sess = ft_sess_delete(tport, rdata->ids.port_id);
	if (!sess) {
		mutex_unlock(&ft_lport_lock);
		return;
	}
	mutex_unlock(&ft_lport_lock);
	transport_deregister_session_configfs(sess->se_sess);
	ft_sess_put(sess);		/* release from table */
	rdata->prli_count--;
	/* XXX TBD - clearing actions.  unit attn, see 4.10 */
}

/*
 * Handle incoming FCP request.
 * Caller has verified that the frame is type FCP.
 */
static void ft_recv(struct fc_lport *lport, struct fc_frame *fp)
{
	struct ft_sess *sess;
	u32 sid = fc_frame_sid(fp);

	pr_debug("sid %x\n", sid);

	sess = ft_sess_get(lport, sid);
	if (!sess) {
		pr_debug("sid %x sess lookup failed\n", sid);
		/* TBD XXX - if FCP_CMND, send PRLO */
		fc_frame_free(fp);
		return;
	}
	ft_recv_req(sess, fp);	/* must do ft_sess_put() */
}

/*
 * Provider ops for libfc.
 */
struct fc4_prov ft_prov = {
	.prli = ft_prli,
	.prlo = ft_prlo,
	.recv = ft_recv,
	.module = THIS_MODULE,
};
Commit	Line	Data
3699d92a KP	1	/*
	2	* Copyright (c) 2010 Cisco Systems, Inc.
	3	*
	4	* This program is free software; you can redistribute it and/or modify it
	5	* under the terms and conditions of the GNU General Public License,
	6	* version 2, as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope it will be useful, but WITHOUT
	9	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	10	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	11	* more details.
	12	*
	13	* You should have received a copy of the GNU General Public License along with
	14	* this program; if not, write to the Free Software Foundation, Inc.,
	15	* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
	16	*/
	17
	18	/* XXX TBD some includes may be extraneous */
	19
	20	#include <linux/module.h>
	21	#include <linux/moduleparam.h>
3699d92a KP	22	#include <linux/utsname.h>
	23	#include <linux/init.h>
	24	#include <linux/slab.h>
	25	#include <linux/kthread.h>
	26	#include <linux/types.h>
	27	#include <linux/string.h>
	28	#include <linux/configfs.h>
	29	#include <linux/ctype.h>
	30	#include <linux/hash.h>
	31	#include <linux/rcupdate.h>
	32	#include <linux/rculist.h>
	33	#include <linux/kref.h>
	34	#include <asm/unaligned.h>
	35	#include <scsi/scsi.h>
	36	#include <scsi/scsi_host.h>
	37	#include <scsi/scsi_device.h>
	38	#include <scsi/scsi_cmnd.h>
	39	#include <scsi/libfc.h>
	40
	41	#include <target/target_core_base.h>
c4795fb2	42	#include <target/target_core_fabric.h>
3699d92a	43	#include <target/target_core_configfs.h>
3699d92a KP	44	#include <target/configfs_macros.h>
3699d92a KP	45
3699d92a KP	46	#include "tcm_fc.h"
	47
	48	static void ft_sess_delete_all(struct ft_tport *);
	49
	50	/*
	51	* Lookup or allocate target local port.
	52	* Caller holds ft_lport_lock.
	53	*/
e3d4440c	54	static struct ft_tport ft_tport_get(struct fc_lport lport)
3699d92a KP	55	{
	56	struct ft_tpg *tpg;
	57	struct ft_tport *tport;
	58	int i;
	59
863555be MR	60	tport = rcu_dereference_protected(lport->prov[FC_TYPE_FCP],
863555be MR	61	lockdep_is_held(&ft_lport_lock));
3699d92a KP	62	if (tport && tport->tpg)
	63	return tport;
	64
	65	tpg = ft_lport_find_tpg(lport);
	66	if (!tpg)
	67	return NULL;
	68
	69	if (tport) {
	70	tport->tpg = tpg;
2c42be2d	71	tpg->tport = tport;
3699d92a KP	72	return tport;
	73	}
	74
	75	tport = kzalloc(sizeof(*tport), GFP_KERNEL);
	76	if (!tport)
	77	return NULL;
	78
	79	tport->lport = lport;
	80	tport->tpg = tpg;
	81	tpg->tport = tport;
	82	for (i = 0; i < FT_SESS_HASH_SIZE; i++)
	83	INIT_HLIST_HEAD(&tport->hash[i]);
	84
	85	rcu_assign_pointer(lport->prov[FC_TYPE_FCP], tport);
	86	return tport;
	87	}
	88
3699d92a KP	89	/*
	90	* Delete a target local port.
	91	* Caller holds ft_lport_lock.
	92	*/
	93	static void ft_tport_delete(struct ft_tport *tport)
	94	{
	95	struct fc_lport *lport;
	96	struct ft_tpg *tpg;
	97
	98	ft_sess_delete_all(tport);
	99	lport = tport->lport;
	100	BUG_ON(tport != lport->prov[FC_TYPE_FCP]);
c04047ec	101	RCU_INIT_POINTER(lport->prov[FC_TYPE_FCP], NULL);
3699d92a KP	102
	103	tpg = tport->tpg;
	104	if (tpg) {
	105	tpg->tport = NULL;
	106	tport->tpg = NULL;
	107	}
a6c76da8	108	kfree_rcu(tport, rcu);
3699d92a KP	109	}
	110
	111	/*
	112	* Add local port.
	113	* Called thru fc_lport_iterate().
	114	*/
	115	void ft_lport_add(struct fc_lport lport, void arg)
	116	{
	117	mutex_lock(&ft_lport_lock);
e3d4440c	118	ft_tport_get(lport);
3699d92a KP	119	mutex_unlock(&ft_lport_lock);
	120	}
	121
	122	/*
	123	* Delete local port.
	124	* Called thru fc_lport_iterate().
	125	*/
	126	void ft_lport_del(struct fc_lport lport, void arg)
	127	{
	128	struct ft_tport *tport;
	129
	130	mutex_lock(&ft_lport_lock);
	131	tport = lport->prov[FC_TYPE_FCP];
	132	if (tport)
	133	ft_tport_delete(tport);
	134	mutex_unlock(&ft_lport_lock);
	135	}
	136
	137	/*
	138	* Notification of local port change from libfc.
	139	* Create or delete local port and associated tport.
	140	*/
	141	int ft_lport_notify(struct notifier_block nb, unsigned long event, void arg)
	142	{
	143	struct fc_lport *lport = arg;
	144
	145	switch (event) {
	146	case FC_LPORT_EV_ADD:
	147	ft_lport_add(lport, NULL);
	148	break;
	149	case FC_LPORT_EV_DEL:
	150	ft_lport_del(lport, NULL);
	151	break;
	152	}
	153	return NOTIFY_DONE;
	154	}
	155
	156	/*
	157	* Hash function for FC_IDs.
	158	*/
	159	static u32 ft_sess_hash(u32 port_id)
	160	{
	161	return hash_32(port_id, FT_SESS_HASH_BITS);
	162	}
	163
	164	/*
	165	* Find session in local port.
	166	* Sessions and hash lists are RCU-protected.
	167	* A reference is taken which must be eventually freed.
	168	*/
	169	static struct ft_sess ft_sess_get(struct fc_lport lport, u32 port_id)
	170	{
	171	struct ft_tport *tport;
	172	struct hlist_head *head;
3699d92a KP	173	struct ft_sess *sess;
	174
	175	rcu_read_lock();
	176	tport = rcu_dereference(lport->prov[FC_TYPE_FCP]);
	177	if (!tport)
	178	goto out;
	179
	180	head = &tport->hash[ft_sess_hash(port_id)];
b67bfe0d	181	hlist_for_each_entry_rcu(sess, head, hash) {
3699d92a KP	182	if (sess->port_id == port_id) {
	183	kref_get(&sess->kref);
	184	rcu_read_unlock();
6708bb27	185	pr_debug("port_id %x found %p\n", port_id, sess);
3699d92a KP	186	return sess;
	187	}
	188	}
	189	out:
	190	rcu_read_unlock();
6708bb27	191	pr_debug("port_id %x not found\n", port_id);
3699d92a KP	192	return NULL;
	193	}
	194
	195	/*
	196	* Allocate session and enter it in the hash for the local port.
	197	* Caller holds ft_lport_lock.
	198	*/
	199	static struct ft_sess ft_sess_create(struct ft_tport tport, u32 port_id,
	200	struct ft_node_acl *acl)
	201	{
	202	struct ft_sess *sess;
	203	struct hlist_head *head;
3699d92a KP	204
3699d92a KP	205	head = &tport->hash[ft_sess_hash(port_id)];
b67bfe0d	206	hlist_for_each_entry_rcu(sess, head, hash)
3699d92a KP	207	if (sess->port_id == port_id)
	208	return sess;
	209
	210	sess = kzalloc(sizeof(*sess), GFP_KERNEL);
	211	if (!sess)
	212	return NULL;
	213
5f544cfa	214	sess->se_sess = transport_init_session_tags(TCM_FC_DEFAULT_TAGS,
e70beee7 NB	215	sizeof(struct ft_cmd),
e70beee7 NB	216	TARGET_PROT_NORMAL);
552523dc	217	if (IS_ERR(sess->se_sess)) {
3699d92a KP	218	kfree(sess);
	219	return NULL;
	220	}
	221	sess->se_sess->se_node_acl = &acl->se_node_acl;
	222	sess->tport = tport;
	223	sess->port_id = port_id;
	224	kref_init(&sess->kref); /* ref for table entry */
	225	hlist_add_head_rcu(&sess->hash, head);
	226	tport->sess_count++;
	227
6708bb27	228	pr_debug("port_id %x sess %p\n", port_id, sess);
3699d92a KP	229
	230	transport_register_session(&tport->tpg->se_tpg, &acl->se_node_acl,
	231	sess->se_sess, sess);
	232	return sess;
	233	}
	234
	235	/*
	236	* Unhash the session.
	237	* Caller holds ft_lport_lock.
	238	*/
	239	static void ft_sess_unhash(struct ft_sess *sess)
	240	{
	241	struct ft_tport *tport = sess->tport;
	242
	243	hlist_del_rcu(&sess->hash);
	244	BUG_ON(!tport->sess_count);
	245	tport->sess_count--;
	246	sess->port_id = -1;
	247	sess->params = 0;
	248	}
	249
	250	/*
	251	* Delete session from hash.
	252	* Caller holds ft_lport_lock.
	253	*/
	254	static struct ft_sess ft_sess_delete(struct ft_tport tport, u32 port_id)
	255	{
	256	struct hlist_head *head;
3699d92a KP	257	struct ft_sess *sess;
	258
	259	head = &tport->hash[ft_sess_hash(port_id)];
b67bfe0d	260	hlist_for_each_entry_rcu(sess, head, hash) {
3699d92a KP	261	if (sess->port_id == port_id) {
	262	ft_sess_unhash(sess);
	263	return sess;
	264	}
	265	}
	266	return NULL;
	267	}
	268
	269	/*
	270	* Delete all sessions from tport.
	271	* Caller holds ft_lport_lock.
	272	*/
	273	static void ft_sess_delete_all(struct ft_tport *tport)
	274	{
	275	struct hlist_head *head;
3699d92a KP	276	struct ft_sess *sess;
	277
	278	for (head = tport->hash;
	279	head < &tport->hash[FT_SESS_HASH_SIZE]; head++) {
b67bfe0d	280	hlist_for_each_entry_rcu(sess, head, hash) {
3699d92a KP	281	ft_sess_unhash(sess);
	282	transport_deregister_session_configfs(sess->se_sess);
	283	ft_sess_put(sess); /* release from table */
	284	}
	285	}
	286	}
	287
	288	/*
	289	* TCM ops for sessions.
	290	*/
	291
	292	/*
	293	* Determine whether session is allowed to be shutdown in the current context.
	294	* Returns non-zero if the session should be shutdown.
	295	*/
	296	int ft_sess_shutdown(struct se_session *se_sess)
	297	{
	298	struct ft_sess *sess = se_sess->fabric_sess_ptr;
	299
6708bb27	300	pr_debug("port_id %x\n", sess->port_id);
3699d92a KP	301	return 1;
	302	}
	303
	304	/*
	305	* Remove session and send PRLO.
	306	* This is called when the ACL is being deleted or queue depth is changing.
	307	*/
	308	void ft_sess_close(struct se_session *se_sess)
	309	{
	310	struct ft_sess *sess = se_sess->fabric_sess_ptr;
3699d92a KP	311	u32 port_id;
	312
	313	mutex_lock(&ft_lport_lock);
3699d92a KP	314	port_id = sess->port_id;
3699d92a KP	315	if (port_id == -1) {
7c7cf3b9	316	mutex_unlock(&ft_lport_lock);
3699d92a KP	317	return;
3699d92a KP	318	}
6708bb27	319	pr_debug("port_id %x\n", port_id);
3699d92a KP	320	ft_sess_unhash(sess);
	321	mutex_unlock(&ft_lport_lock);
	322	transport_deregister_session_configfs(se_sess);
	323	ft_sess_put(sess);
	324	/* XXX Send LOGO or PRLO */
	325	synchronize_rcu(); /* let transport deregister happen */
	326	}
	327
3699d92a KP	328	u32 ft_sess_get_index(struct se_session *se_sess)
	329	{
	330	struct ft_sess *sess = se_sess->fabric_sess_ptr;
	331
	332	return sess->port_id; /* XXX TBD probably not what is needed */
	333	}
	334
	335	u32 ft_sess_get_port_name(struct se_session *se_sess,
	336	unsigned char *buf, u32 len)
	337	{
	338	struct ft_sess *sess = se_sess->fabric_sess_ptr;
	339
	340	return ft_format_wwn(buf, len, sess->port_name);
	341	}
	342
3699d92a KP	343	/*
	344	* libfc ops involving sessions.
	345	*/
	346
	347	static int ft_prli_locked(struct fc_rport_priv *rdata, u32 spp_len,
	348	const struct fc_els_spp rspp, struct fc_els_spp spp)
	349	{
	350	struct ft_tport *tport;
	351	struct ft_sess *sess;
	352	struct ft_node_acl *acl;
	353	u32 fcp_parm;
	354
e3d4440c	355	tport = ft_tport_get(rdata->local_port);
3699d92a	356	if (!tport)
edec8dfe	357	goto not_target; /* not a target for this local port */
3699d92a KP	358
	359	acl = ft_acl_get(tport->tpg, rdata);
	360	if (!acl)
edec8dfe	361	goto not_target; /* no target for this remote */
3699d92a KP	362
	363	if (!rspp)
	364	goto fill;
	365
	366	if (rspp->spp_flags & (FC_SPP_OPA_VAL \| FC_SPP_RPA_VAL))
	367	return FC_SPP_RESP_NO_PA;
	368
	369	/*
	370	* If both target and initiator bits are off, the SPP is invalid.
	371	*/
	372	fcp_parm = ntohl(rspp->spp_params);
	373	if (!(fcp_parm & (FCP_SPPF_INIT_FCN \| FCP_SPPF_TARG_FCN)))
	374	return FC_SPP_RESP_INVL;
	375
	376	/*
	377	* Create session (image pair) only if requested by
	378	* EST_IMG_PAIR flag and if the requestor is an initiator.
	379	*/
	380	if (rspp->spp_flags & FC_SPP_EST_IMG_PAIR) {
	381	spp->spp_flags \|= FC_SPP_EST_IMG_PAIR;
	382	if (!(fcp_parm & FCP_SPPF_INIT_FCN))
	383	return FC_SPP_RESP_CONF;
	384	sess = ft_sess_create(tport, rdata->ids.port_id, acl);
	385	if (!sess)
	386	return FC_SPP_RESP_RES;
	387	if (!sess->params)
	388	rdata->prli_count++;
	389	sess->params = fcp_parm;
	390	sess->port_name = rdata->ids.port_name;
	391	sess->max_frame = rdata->maxframe_size;
	392
	393	/* XXX TBD - clearing actions. unit attn, see 4.10 */
	394	}
	395
	396	/*
	397	* OR in our service parameters with other provider (initiator), if any.
3699d92a KP	398	*/
	399	fill:
	400	fcp_parm = ntohl(spp->spp_params);
f2eeba21	401	fcp_parm &= ~FCP_SPPF_RETRY;
3699d92a KP	402	spp->spp_params = htonl(fcp_parm \| FCP_SPPF_TARG_FCN);
3699d92a KP	403	return FC_SPP_RESP_ACK;
edec8dfe MR	404
	405	not_target:
	406	fcp_parm = ntohl(spp->spp_params);
	407	fcp_parm &= ~FCP_SPPF_TARG_FCN;
	408	spp->spp_params = htonl(fcp_parm);
	409	return 0;
3699d92a KP	410	}
	411
	412	/**
	413	* tcm_fcp_prli() - Handle incoming or outgoing PRLI for the FCP target
	414	* @rdata: remote port private
	415	* @spp_len: service parameter page length
	416	* @rspp: received service parameter page (NULL for outgoing PRLI)
	417	* @spp: response service parameter page
	418	*
	419	* Returns spp response code.
	420	*/
	421	static int ft_prli(struct fc_rport_priv *rdata, u32 spp_len,
	422	const struct fc_els_spp rspp, struct fc_els_spp spp)
	423	{
	424	int ret;
	425
	426	mutex_lock(&ft_lport_lock);
	427	ret = ft_prli_locked(rdata, spp_len, rspp, spp);
	428	mutex_unlock(&ft_lport_lock);
6708bb27	429	pr_debug("port_id %x flags %x ret %x\n",
3699d92a KP	430	rdata->ids.port_id, rspp ? rspp->spp_flags : 0, ret);
	431	return ret;
	432	}
	433
3699d92a KP	434	static void ft_sess_free(struct kref *kref)
	435	{
	436	struct ft_sess *sess = container_of(kref, struct ft_sess, kref);
	437
9f4ad44b	438	transport_deregister_session(sess->se_sess);
a6ad57ef	439	kfree_rcu(sess, rcu);
3699d92a KP	440	}
	441
	442	void ft_sess_put(struct ft_sess *sess)
	443	{
	444	int sess_held = atomic_read(&sess->kref.refcount);
	445
	446	BUG_ON(!sess_held);
	447	kref_put(&sess->kref, ft_sess_free);
	448	}
	449
	450	static void ft_prlo(struct fc_rport_priv *rdata)
	451	{
	452	struct ft_sess *sess;
	453	struct ft_tport *tport;
	454
	455	mutex_lock(&ft_lport_lock);
08a16208 DE	456	tport = rcu_dereference_protected(rdata->local_port->prov[FC_TYPE_FCP],
	457	lockdep_is_held(&ft_lport_lock));
	458
3699d92a KP	459	if (!tport) {
	460	mutex_unlock(&ft_lport_lock);
	461	return;
	462	}
	463	sess = ft_sess_delete(tport, rdata->ids.port_id);
	464	if (!sess) {
	465	mutex_unlock(&ft_lport_lock);
	466	return;
	467	}
	468	mutex_unlock(&ft_lport_lock);
	469	transport_deregister_session_configfs(sess->se_sess);
	470	ft_sess_put(sess); /* release from table */
	471	rdata->prli_count--;
	472	/* XXX TBD - clearing actions. unit attn, see 4.10 */
	473	}
	474
	475	/*
	476	* Handle incoming FCP request.
	477	* Caller has verified that the frame is type FCP.
	478	*/
	479	static void ft_recv(struct fc_lport lport, struct fc_frame fp)
	480	{
	481	struct ft_sess *sess;
	482	u32 sid = fc_frame_sid(fp);
	483
6708bb27	484	pr_debug("sid %x\n", sid);
3699d92a KP	485
	486	sess = ft_sess_get(lport, sid);
	487	if (!sess) {
6708bb27	488	pr_debug("sid %x sess lookup failed\n", sid);
3699d92a KP	489	/* TBD XXX - if FCP_CMND, send PRLO */
	490	fc_frame_free(fp);
	491	return;
	492	}
	493	ft_recv_req(sess, fp); /* must do ft_sess_put() */
	494	}
	495
	496	/*
	497	* Provider ops for libfc.
	498	*/
	499	struct fc4_prov ft_prov = {
	500	.prli = ft_prli,
	501	.prlo = ft_prlo,
	502	.recv = ft_recv,
	503	.module = THIS_MODULE,
	504	};