--- /dev/null
+/*
+ * 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,
+};
Code Review / kvmfornfv.git / blobdiff