1 files changed, 541 insertions, 0 deletions

diff --git a/drivers/target/tcm_fc/tfc_sess.c b/drivers/target/tcm_fc/tfc_sess.c
new file mode 100644
index 000000000000..7491e21cc6ae
--- /dev/null
+++ b/drivers/target/tcm_fc/tfc_sess.c
@@ -0,0 +1,541 @@
+/*
+ * 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/version.h>
+#include <generated/utsrelease.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_transport.h>
+#include <target/target_core_fabric_ops.h>
+#include <target/target_core_device.h>
+#include <target/target_core_tpg.h>
+#include <target/target_core_configfs.h>
+#include <target/target_core_base.h>
+#include <target/configfs_macros.h>
+
+#include <scsi/libfc.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_create(struct fc_lport *lport)
+{
+        struct ft_tpg *tpg;
+        struct ft_tport *tport;
+        int i;
+
+        tport = rcu_dereference(lport->prov[FC_TYPE_FCP]);
+        if (tport && tport->tpg)
+                return tport;
+
+        tpg = ft_lport_find_tpg(lport);
+        if (!tpg)
+                return NULL;
+
+        if (tport) {
+                tport->tpg = tpg;
+                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;
+}
+
+/*
+ * Free tport via RCU.
+ */
+static void ft_tport_rcu_free(struct rcu_head *rcu)
+{
+        struct ft_tport *tport = container_of(rcu, struct ft_tport, rcu);
+
+        kfree(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_assign_pointer(lport->prov[FC_TYPE_FCP], NULL);
+
+        tpg = tport->tpg;
+        if (tpg) {
+                tpg->tport = NULL;
+                tport->tpg = NULL;
+        }
+        call_rcu(&tport->rcu, ft_tport_rcu_free);
+}
+
+/*
+ * 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_create(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 hlist_node *pos;
+        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, pos, head, hash) {
+                if (sess->port_id == port_id) {
+                        kref_get(&sess->kref);
+                        rcu_read_unlock();
+                        FT_SESS_DBG("port_id %x found %p\n", port_id, sess);
+                        return sess;
+                }
+        }
+out:
+        rcu_read_unlock();
+        FT_SESS_DBG("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;
+        struct hlist_node *pos;
+
+        head = &tport->hash[ft_sess_hash(port_id)];
+        hlist_for_each_entry_rcu(sess, pos, 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();
+        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++;
+
+        FT_SESS_DBG("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 hlist_node *pos;
+        struct ft_sess *sess;
+
+        head = &tport->hash[ft_sess_hash(port_id)];
+        hlist_for_each_entry_rcu(sess, pos, 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 hlist_node *pos;
+        struct ft_sess *sess;
+
+        for (head = tport->hash;
+             head < &tport->hash[FT_SESS_HASH_SIZE]; head++) {
+                hlist_for_each_entry_rcu(sess, pos, 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;
+
+        FT_SESS_DBG("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;
+        struct fc_lport *lport;
+        u32 port_id;
+
+        mutex_lock(&ft_lport_lock);
+        lport = sess->tport->lport;
+        port_id = sess->port_id;
+        if (port_id == -1) {
+                mutex_unlock(&ft_lport_lock);
+                return;
+        }
+        FT_SESS_DBG("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 */
+}
+
+void ft_sess_stop(struct se_session *se_sess, int sess_sleep, int conn_sleep)
+{
+        struct ft_sess *sess = se_sess->fabric_sess_ptr;
+
+        FT_SESS_DBG("port_id %x\n", sess->port_id);
+}
+
+int ft_sess_logged_in(struct se_session *se_sess)
+{
+        struct ft_sess *sess = se_sess->fabric_sess_ptr;
+
+        return sess->port_id != -1;
+}
+
+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);
+}
+
+void ft_sess_set_erl0(struct se_session *se_sess)
+{
+        /* XXX TBD called when out of memory */
+}
+
+/*
+ * 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_create(rdata->local_port);
+        if (!tport)
+                return 0;       /* not a target for this local port */
+
+        acl = ft_acl_get(tport->tpg, rdata);
+        if (!acl)
+                return 0;
+
+        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.
+         * TBD XXX - indicate RETRY capability?
+         */
+fill:
+        fcp_parm = ntohl(spp->spp_params);
+        spp->spp_params = htonl(fcp_parm | FCP_SPPF_TARG_FCN);
+        return FC_SPP_RESP_ACK;
+}
+
+/**
+ * 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);
+        FT_SESS_DBG("port_id %x flags %x ret %x\n",
+               rdata->ids.port_id, rspp ? rspp->spp_flags : 0, ret);
+        return ret;
+}
+
+static void ft_sess_rcu_free(struct rcu_head *rcu)
+{
+        struct ft_sess *sess = container_of(rcu, struct ft_sess, rcu);
+
+        transport_deregister_session(sess->se_sess);
+        kfree(sess);
+}
+
+static void ft_sess_free(struct kref *kref)
+{
+        struct ft_sess *sess = container_of(kref, struct ft_sess, kref);
+
+        call_rcu(&sess->rcu, ft_sess_rcu_free);
+}
+
+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(rdata->local_port->prov[FC_TYPE_FCP]);
+        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);
+
+        FT_SESS_DBG("sid %x\n", sid);
+
+        sess = ft_sess_get(lport, sid);
+        if (!sess) {
+                FT_SESS_DBG("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,
+};