iscsi-target: Convert iscsi_thread_set usage to kthread.h

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>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/include/target/iscsi/iscsi_target_core.h b/include/target/iscsi/iscsi_target_core.h
index d3583d3ee193..dd0f3abde75d 100644
--- a/include/target/iscsi/iscsi_target_core.h
+++ b/include/target/iscsi/iscsi_target_core.h
@@ -602,6 +602,11 @@ 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;
@@ -871,10 +876,12 @@ 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;