--- /dev/null
+From 88dcd2dab5c23b1c9cfc396246d8f476c872f0ca Mon Sep 17 00:00:00 2001
+From: Nicholas Bellinger <nab@linux-iscsi.org>
+Date: Thu, 26 Feb 2015 22:19:15 -0800
+Subject: iscsi-target: Convert iscsi_thread_set usage to kthread.h
+
+From: Nicholas Bellinger <nab@linux-iscsi.org>
+
+commit 88dcd2dab5c23b1c9cfc396246d8f476c872f0ca upstream.
+
+This patch converts iscsi-target code to use modern kthread.h API
+callers for creating RX/TX threads for each new iscsi_conn descriptor,
+and releasing associated RX/TX threads during connection shutdown.
+
+This is done using iscsit_start_kthreads() -> kthread_run() to start
+new kthreads from within iscsi_post_login_handler(), and invoking
+kthread_stop() from existing iscsit_close_connection() code.
+
+Also, convert iscsit_logout_post_handler_closesession() code to use
+cmpxchg when determing when iscsit_cause_connection_reinstatement()
+needs to sleep waiting for completion.
+
+Reported-by: Sagi Grimberg <sagig@mellanox.com>
+Tested-by: Sagi Grimberg <sagig@mellanox.com>
+Cc: Slava Shwartsman <valyushash@gmail.com>
+Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+
+---
+ drivers/target/iscsi/iscsi_target.c | 104 ++++++++++++------------------
+ drivers/target/iscsi/iscsi_target_core.h | 7 ++
+ drivers/target/iscsi/iscsi_target_erl0.c | 13 ++-
+ drivers/target/iscsi/iscsi_target_login.c | 59 +++++++++++++++--
+ 4 files changed, 114 insertions(+), 69 deletions(-)
+
+--- a/drivers/target/iscsi/iscsi_target.c
++++ b/drivers/target/iscsi/iscsi_target.c
+@@ -518,7 +518,7 @@ static struct iscsit_transport iscsi_tar
+
+ static int __init iscsi_target_init_module(void)
+ {
+- int ret = 0;
++ int ret = 0, size;
+
+ pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
+
+@@ -527,6 +527,7 @@ static int __init iscsi_target_init_modu
+ pr_err("Unable to allocate memory for iscsit_global\n");
+ return -1;
+ }
++ spin_lock_init(&iscsit_global->ts_bitmap_lock);
+ mutex_init(&auth_id_lock);
+ spin_lock_init(&sess_idr_lock);
+ idr_init(&tiqn_idr);
+@@ -536,15 +537,11 @@ static int __init iscsi_target_init_modu
+ if (ret < 0)
+ goto out;
+
+- ret = iscsi_thread_set_init();
+- if (ret < 0)
++ size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
++ iscsit_global->ts_bitmap = vzalloc(size);
++ if (!iscsit_global->ts_bitmap) {
++ pr_err("Unable to allocate iscsit_global->ts_bitmap\n");
+ goto configfs_out;
+-
+- if (iscsi_allocate_thread_sets(TARGET_THREAD_SET_COUNT) !=
+- TARGET_THREAD_SET_COUNT) {
+- pr_err("iscsi_allocate_thread_sets() returned"
+- " unexpected value!\n");
+- goto ts_out1;
+ }
+
+ lio_qr_cache = kmem_cache_create("lio_qr_cache",
+@@ -553,7 +550,7 @@ static int __init iscsi_target_init_modu
+ if (!lio_qr_cache) {
+ pr_err("nable to kmem_cache_create() for"
+ " lio_qr_cache\n");
+- goto ts_out2;
++ goto bitmap_out;
+ }
+
+ lio_dr_cache = kmem_cache_create("lio_dr_cache",
+@@ -597,10 +594,8 @@ dr_out:
+ kmem_cache_destroy(lio_dr_cache);
+ qr_out:
+ kmem_cache_destroy(lio_qr_cache);
+-ts_out2:
+- iscsi_deallocate_thread_sets();
+-ts_out1:
+- iscsi_thread_set_free();
++bitmap_out:
++ vfree(iscsit_global->ts_bitmap);
+ configfs_out:
+ iscsi_target_deregister_configfs();
+ out:
+@@ -610,8 +605,6 @@ out:
+
+ static void __exit iscsi_target_cleanup_module(void)
+ {
+- iscsi_deallocate_thread_sets();
+- iscsi_thread_set_free();
+ iscsit_release_discovery_tpg();
+ iscsit_unregister_transport(&iscsi_target_transport);
+ kmem_cache_destroy(lio_qr_cache);
+@@ -621,6 +614,7 @@ static void __exit iscsi_target_cleanup_
+
+ iscsi_target_deregister_configfs();
+
++ vfree(iscsit_global->ts_bitmap);
+ kfree(iscsit_global);
+ }
+
+@@ -3653,17 +3647,16 @@ static int iscsit_send_reject(
+
+ void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
+ {
+- struct iscsi_thread_set *ts = conn->thread_set;
+ int ord, cpu;
+ /*
+- * thread_id is assigned from iscsit_global->ts_bitmap from
+- * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
++ * bitmap_id is assigned from iscsit_global->ts_bitmap from
++ * within iscsit_start_kthreads()
+ *
+- * Here we use thread_id to determine which CPU that this
+- * iSCSI connection's iscsi_thread_set will be scheduled to
++ * Here we use bitmap_id to determine which CPU that this
++ * iSCSI connection's RX/TX threads will be scheduled to
+ * execute upon.
+ */
+- ord = ts->thread_id % cpumask_weight(cpu_online_mask);
++ ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
+ for_each_online_cpu(cpu) {
+ if (ord-- == 0) {
+ cpumask_set_cpu(cpu, conn->conn_cpumask);
+@@ -3855,7 +3848,7 @@ check_rsp_state:
+ switch (state) {
+ case ISTATE_SEND_LOGOUTRSP:
+ if (!iscsit_logout_post_handler(cmd, conn))
+- goto restart;
++ return -ECONNRESET;
+ /* fall through */
+ case ISTATE_SEND_STATUS:
+ case ISTATE_SEND_ASYNCMSG:
+@@ -3883,8 +3876,6 @@ check_rsp_state:
+
+ err:
+ return -1;
+-restart:
+- return -EAGAIN;
+ }
+
+ static int iscsit_handle_response_queue(struct iscsi_conn *conn)
+@@ -3911,21 +3902,13 @@ static int iscsit_handle_response_queue(
+ int iscsi_target_tx_thread(void *arg)
+ {
+ int ret = 0;
+- struct iscsi_conn *conn;
+- struct iscsi_thread_set *ts = arg;
++ struct iscsi_conn *conn = arg;
+ /*
+ * Allow ourselves to be interrupted by SIGINT so that a
+ * connection recovery / failure event can be triggered externally.
+ */
+ allow_signal(SIGINT);
+
+-restart:
+- conn = iscsi_tx_thread_pre_handler(ts);
+- if (!conn)
+- goto out;
+-
+- ret = 0;
+-
+ while (!kthread_should_stop()) {
+ /*
+ * Ensure that both TX and RX per connection kthreads
+@@ -3934,11 +3917,9 @@ restart:
+ iscsit_thread_check_cpumask(conn, current, 1);
+
+ wait_event_interruptible(conn->queues_wq,
+- !iscsit_conn_all_queues_empty(conn) ||
+- ts->status == ISCSI_THREAD_SET_RESET);
++ !iscsit_conn_all_queues_empty(conn));
+
+- if ((ts->status == ISCSI_THREAD_SET_RESET) ||
+- signal_pending(current))
++ if (signal_pending(current))
+ goto transport_err;
+
+ get_immediate:
+@@ -3949,15 +3930,14 @@ get_immediate:
+ ret = iscsit_handle_response_queue(conn);
+ if (ret == 1)
+ goto get_immediate;
+- else if (ret == -EAGAIN)
+- goto restart;
++ else if (ret == -ECONNRESET)
++ goto out;
+ else if (ret < 0)
+ goto transport_err;
+ }
+
+ transport_err:
+ iscsit_take_action_for_connection_exit(conn);
+- goto restart;
+ out:
+ return 0;
+ }
+@@ -4046,8 +4026,7 @@ int iscsi_target_rx_thread(void *arg)
+ int ret;
+ u8 buffer[ISCSI_HDR_LEN], opcode;
+ u32 checksum = 0, digest = 0;
+- struct iscsi_conn *conn = NULL;
+- struct iscsi_thread_set *ts = arg;
++ struct iscsi_conn *conn = arg;
+ struct kvec iov;
+ /*
+ * Allow ourselves to be interrupted by SIGINT so that a
+@@ -4055,11 +4034,6 @@ int iscsi_target_rx_thread(void *arg)
+ */
+ allow_signal(SIGINT);
+
+-restart:
+- conn = iscsi_rx_thread_pre_handler(ts);
+- if (!conn)
+- goto out;
+-
+ if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) {
+ struct completion comp;
+ int rc;
+@@ -4069,7 +4043,7 @@ restart:
+ if (rc < 0)
+ goto transport_err;
+
+- goto out;
++ goto transport_err;
+ }
+
+ while (!kthread_should_stop()) {
+@@ -4145,8 +4119,6 @@ transport_err:
+ if (!signal_pending(current))
+ atomic_set(&conn->transport_failed, 1);
+ iscsit_take_action_for_connection_exit(conn);
+- goto restart;
+-out:
+ return 0;
+ }
+
+@@ -4208,7 +4180,24 @@ int iscsit_close_connection(
+ if (conn->conn_transport->transport_type == ISCSI_TCP)
+ complete(&conn->conn_logout_comp);
+
+- iscsi_release_thread_set(conn);
++ if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
++ if (conn->tx_thread &&
++ cmpxchg(&conn->tx_thread_active, true, false)) {
++ send_sig(SIGINT, conn->tx_thread, 1);
++ kthread_stop(conn->tx_thread);
++ }
++ } else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
++ if (conn->rx_thread &&
++ cmpxchg(&conn->rx_thread_active, true, false)) {
++ send_sig(SIGINT, conn->rx_thread, 1);
++ kthread_stop(conn->rx_thread);
++ }
++ }
++
++ spin_lock(&iscsit_global->ts_bitmap_lock);
++ bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
++ get_order(1));
++ spin_unlock(&iscsit_global->ts_bitmap_lock);
+
+ iscsit_stop_timers_for_cmds(conn);
+ iscsit_stop_nopin_response_timer(conn);
+@@ -4487,15 +4476,13 @@ static void iscsit_logout_post_handler_c
+ struct iscsi_conn *conn)
+ {
+ struct iscsi_session *sess = conn->sess;
+-
+- iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
+- iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
++ int sleep = cmpxchg(&conn->tx_thread_active, true, false);
+
+ atomic_set(&conn->conn_logout_remove, 0);
+ complete(&conn->conn_logout_comp);
+
+ iscsit_dec_conn_usage_count(conn);
+- iscsit_stop_session(sess, 1, 1);
++ iscsit_stop_session(sess, sleep, sleep);
+ iscsit_dec_session_usage_count(sess);
+ target_put_session(sess->se_sess);
+ }
+@@ -4503,13 +4490,12 @@ static void iscsit_logout_post_handler_c
+ static void iscsit_logout_post_handler_samecid(
+ struct iscsi_conn *conn)
+ {
+- iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
+- iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
++ int sleep = cmpxchg(&conn->tx_thread_active, true, false);
+
+ atomic_set(&conn->conn_logout_remove, 0);
+ complete(&conn->conn_logout_comp);
+
+- iscsit_cause_connection_reinstatement(conn, 1);
++ iscsit_cause_connection_reinstatement(conn, sleep);
+ iscsit_dec_conn_usage_count(conn);
+ }
+
+--- a/drivers/target/iscsi/iscsi_target_core.h
++++ b/drivers/target/iscsi/iscsi_target_core.h
+@@ -601,6 +601,11 @@ struct iscsi_conn {
+ struct iscsi_session *sess;
+ /* Pointer to thread_set in use for this conn's threads */
+ struct iscsi_thread_set *thread_set;
++ int bitmap_id;
++ int rx_thread_active;
++ struct task_struct *rx_thread;
++ int tx_thread_active;
++ struct task_struct *tx_thread;
+ /* list_head for session connection list */
+ struct list_head conn_list;
+ } ____cacheline_aligned;
+@@ -869,10 +874,12 @@ struct iscsit_global {
+ /* Unique identifier used for the authentication daemon */
+ u32 auth_id;
+ u32 inactive_ts;
++#define ISCSIT_BITMAP_BITS 262144
+ /* Thread Set bitmap count */
+ int ts_bitmap_count;
+ /* Thread Set bitmap pointer */
+ unsigned long *ts_bitmap;
++ spinlock_t ts_bitmap_lock;
+ /* Used for iSCSI discovery session authentication */
+ struct iscsi_node_acl discovery_acl;
+ struct iscsi_portal_group *discovery_tpg;
+--- a/drivers/target/iscsi/iscsi_target_erl0.c
++++ b/drivers/target/iscsi/iscsi_target_erl0.c
+@@ -864,7 +864,10 @@ void iscsit_connection_reinstatement_rcf
+ }
+ spin_unlock_bh(&conn->state_lock);
+
+- iscsi_thread_set_force_reinstatement(conn);
++ if (conn->tx_thread && conn->tx_thread_active)
++ send_sig(SIGINT, conn->tx_thread, 1);
++ if (conn->rx_thread && conn->rx_thread_active)
++ send_sig(SIGINT, conn->rx_thread, 1);
+
+ sleep:
+ wait_for_completion(&conn->conn_wait_rcfr_comp);
+@@ -889,10 +892,10 @@ void iscsit_cause_connection_reinstateme
+ return;
+ }
+
+- if (iscsi_thread_set_force_reinstatement(conn) < 0) {
+- spin_unlock_bh(&conn->state_lock);
+- return;
+- }
++ if (conn->tx_thread && conn->tx_thread_active)
++ send_sig(SIGINT, conn->tx_thread, 1);
++ if (conn->rx_thread && conn->rx_thread_active)
++ send_sig(SIGINT, conn->rx_thread, 1);
+
+ atomic_set(&conn->connection_reinstatement, 1);
+ if (!sleep) {
+--- a/drivers/target/iscsi/iscsi_target_login.c
++++ b/drivers/target/iscsi/iscsi_target_login.c
+@@ -681,6 +681,51 @@ static void iscsi_post_login_start_timer
+ iscsit_start_nopin_timer(conn);
+ }
+
++int iscsit_start_kthreads(struct iscsi_conn *conn)
++{
++ int ret = 0;
++
++ spin_lock(&iscsit_global->ts_bitmap_lock);
++ conn->bitmap_id = bitmap_find_free_region(iscsit_global->ts_bitmap,
++ ISCSIT_BITMAP_BITS, get_order(1));
++ spin_unlock(&iscsit_global->ts_bitmap_lock);
++
++ if (conn->bitmap_id < 0) {
++ pr_err("bitmap_find_free_region() failed for"
++ " iscsit_start_kthreads()\n");
++ return -ENOMEM;
++ }
++
++ conn->tx_thread = kthread_run(iscsi_target_tx_thread, conn,
++ "%s", ISCSI_TX_THREAD_NAME);
++ if (IS_ERR(conn->tx_thread)) {
++ pr_err("Unable to start iscsi_target_tx_thread\n");
++ ret = PTR_ERR(conn->tx_thread);
++ goto out_bitmap;
++ }
++ conn->tx_thread_active = true;
++
++ conn->rx_thread = kthread_run(iscsi_target_rx_thread, conn,
++ "%s", ISCSI_RX_THREAD_NAME);
++ if (IS_ERR(conn->rx_thread)) {
++ pr_err("Unable to start iscsi_target_rx_thread\n");
++ ret = PTR_ERR(conn->rx_thread);
++ goto out_tx;
++ }
++ conn->rx_thread_active = true;
++
++ return 0;
++out_tx:
++ kthread_stop(conn->tx_thread);
++ conn->tx_thread_active = false;
++out_bitmap:
++ spin_lock(&iscsit_global->ts_bitmap_lock);
++ bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
++ get_order(1));
++ spin_unlock(&iscsit_global->ts_bitmap_lock);
++ return ret;
++}
++
+ int iscsi_post_login_handler(
+ struct iscsi_np *np,
+ struct iscsi_conn *conn,
+@@ -691,7 +736,7 @@ int iscsi_post_login_handler(
+ struct se_session *se_sess = sess->se_sess;
+ struct iscsi_portal_group *tpg = sess->tpg;
+ struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
+- struct iscsi_thread_set *ts;
++ int rc;
+
+ iscsit_inc_conn_usage_count(conn);
+
+@@ -706,7 +751,6 @@ int iscsi_post_login_handler(
+ /*
+ * SCSI Initiator -> SCSI Target Port Mapping
+ */
+- ts = iscsi_get_thread_set();
+ if (!zero_tsih) {
+ iscsi_set_session_parameters(sess->sess_ops,
+ conn->param_list, 0);
+@@ -733,9 +777,11 @@ int iscsi_post_login_handler(
+ sess->sess_ops->InitiatorName);
+ spin_unlock_bh(&sess->conn_lock);
+
+- iscsi_post_login_start_timers(conn);
++ rc = iscsit_start_kthreads(conn);
++ if (rc)
++ return rc;
+
+- iscsi_activate_thread_set(conn, ts);
++ iscsi_post_login_start_timers(conn);
+ /*
+ * Determine CPU mask to ensure connection's RX and TX kthreads
+ * are scheduled on the same CPU.
+@@ -792,8 +838,11 @@ int iscsi_post_login_handler(
+ " iSCSI Target Portal Group: %hu\n", tpg->nsessions, tpg->tpgt);
+ spin_unlock_bh(&se_tpg->session_lock);
+
++ rc = iscsit_start_kthreads(conn);
++ if (rc)
++ return rc;
++
+ iscsi_post_login_start_timers(conn);
+- iscsi_activate_thread_set(conn, ts);
+ /*
+ * Determine CPU mask to ensure connection's RX and TX kthreads
+ * are scheduled on the same CPU.
--- /dev/null
+From 2f1b6b7d9a815f341b18dfd26a363f37d4d3c96a Mon Sep 17 00:00:00 2001
+From: Sagi Grimberg <sagig@mellanox.com>
+Date: Thu, 4 Jun 2015 19:49:20 +0300
+Subject: iser-target: release stale iser connections
+
+From: Sagi Grimberg <sagig@mellanox.com>
+
+commit 2f1b6b7d9a815f341b18dfd26a363f37d4d3c96a upstream.
+
+When receiving a new iser connect request we serialize
+the pending requests by adding the newly created iser connection
+to the np accept list and let the login thread process the connect
+request one by one (np_accept_wait).
+
+In case we received a disconnect request before the iser_conn
+has begun processing (still linked in np_accept_list) we should
+detach it from the list and clean it up and not have the login
+thread process a stale connection. We do it only when the connection
+state is not already terminating (initiator driven disconnect) as
+this might lead us to access np_accept_mutex after the np was released
+in live shutdown scenarios.
+
+Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
+Signed-off-by: Jenny Falkovich <jennyf@mellanox.com>
+Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+
+---
+ drivers/infiniband/ulp/isert/ib_isert.c | 18 +++++++++++++++++-
+ 1 file changed, 17 insertions(+), 1 deletion(-)
+
+--- a/drivers/infiniband/ulp/isert/ib_isert.c
++++ b/drivers/infiniband/ulp/isert/ib_isert.c
+@@ -59,6 +59,8 @@ static int
+ isert_rdma_accept(struct isert_conn *isert_conn);
+ struct rdma_cm_id *isert_setup_id(struct isert_np *isert_np);
+
++static void isert_release_work(struct work_struct *work);
++
+ static void
+ isert_qp_event_callback(struct ib_event *e, void *context)
+ {
+@@ -534,6 +536,7 @@ isert_connect_request(struct rdma_cm_id
+ mutex_init(&isert_conn->conn_mutex);
+ spin_lock_init(&isert_conn->conn_lock);
+ INIT_LIST_HEAD(&isert_conn->conn_fr_pool);
++ INIT_WORK(&isert_conn->release_work, isert_release_work);
+
+ isert_conn->conn_cm_id = cma_id;
+ isert_conn->responder_resources = event->param.conn.responder_resources;
+@@ -800,6 +803,7 @@ isert_disconnected_handler(struct rdma_c
+ {
+ struct isert_np *isert_np = cma_id->context;
+ struct isert_conn *isert_conn;
++ bool terminating = false;
+
+ if (isert_np->np_cm_id == cma_id)
+ return isert_np_cma_handler(cma_id->context, event);
+@@ -807,12 +811,25 @@ isert_disconnected_handler(struct rdma_c
+ isert_conn = cma_id->qp->qp_context;
+
+ mutex_lock(&isert_conn->conn_mutex);
++ terminating = (isert_conn->state == ISER_CONN_TERMINATING);
+ isert_conn_terminate(isert_conn);
+ mutex_unlock(&isert_conn->conn_mutex);
+
+ pr_info("conn %p completing conn_wait\n", isert_conn);
+ complete(&isert_conn->conn_wait);
+
++ if (terminating)
++ goto out;
++
++ mutex_lock(&isert_np->np_accept_mutex);
++ if (!list_empty(&isert_conn->conn_accept_node)) {
++ list_del_init(&isert_conn->conn_accept_node);
++ isert_put_conn(isert_conn);
++ queue_work(isert_release_wq, &isert_conn->release_work);
++ }
++ mutex_unlock(&isert_np->np_accept_mutex);
++
++out:
+ return 0;
+ }
+
+@@ -2948,7 +2965,6 @@ static void isert_wait_conn(struct iscsi
+
+ wait_for_completion(&isert_conn->conn_wait_comp_err);
+
+- INIT_WORK(&isert_conn->release_work, isert_release_work);
+ queue_work(isert_release_wq, &isert_conn->release_work);
+ }
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
