[SCSI] libiscsi: do not block session during logout

There is not need to block the session during logout. Since
we are going to fail the commands that were blocked just fail them
immediately instead.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

diff --git a/drivers/infiniband/ulp/iser/iser_initiator.c b/drivers/infiniband/ulp/iser/iser_initiator.c
index a6f2303ed14a40016fe09bd1e13757fe6b49467b..47f716ca0026f256636371ec6ea8c0bdcc4ee579 100644 (file)
--- a/drivers/infiniband/ulp/iser/iser_initiator.c
+++ b/drivers/infiniband/ulp/iser/iser_initiator.c
@@ -621,9 +621,7 @@ void iser_snd_completion(struct iser_desc *tx_desc)
                        struct iscsi_session *session = conn->session;
 
                        spin_lock(&conn->session->lock);
-                       list_del(&mtask->running);
-                       __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
-                                   sizeof(void*));
+                       iscsi_free_mgmt_task(conn, mtask);
                        spin_unlock(&session->lock);
                }
        }

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index f79a457099e691b61a6dd5923c9db5e20279aa4e..90eae8e0d978892e9f393a0f83ec4c5c46c6b84a 100644 (file)
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -1349,9 +1349,7 @@ iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
                struct iscsi_session *session = conn->session;
 
                spin_lock_bh(&session->lock);
-               list_del(&conn->mtask->running);
-               __kfifo_put(session->mgmtpool.queue, (void*)&conn->mtask,
-                           sizeof(void*));
+               iscsi_free_mgmt_task(conn, mtask);
                spin_unlock_bh(&session->lock);
        }
        return 0;

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index d43f909a022c2916e7fe97185809c6e8f826abc9..b7a2b9ad3a979da075d1d24f2d69115ae9040a3c 100644 (file)
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -37,9 +37,6 @@
 #include <scsi/scsi_transport_iscsi.h>
 #include <scsi/libiscsi.h>
 
-static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
-                        int err);
-
 struct iscsi_session *
 class_to_transport_session(struct iscsi_cls_session *cls_session)
 {
@@ -274,6 +271,53 @@ static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
                iscsi_complete_command(ctask);
 }
 
+/*
+ * session lock must be held
+ */
+static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
+                        int err)
+{
+       struct scsi_cmnd *sc;
+
+       sc = ctask->sc;
+       if (!sc)
+               return;
+
+       if (ctask->state == ISCSI_TASK_PENDING)
+               /*
+                * cmd never made it to the xmit thread, so we should not count
+                * the cmd in the sequencing
+                */
+               conn->session->queued_cmdsn--;
+       else
+               conn->session->tt->cleanup_cmd_task(conn, ctask);
+
+       sc->result = err;
+       scsi_set_resid(sc, scsi_bufflen(sc));
+       if (conn->ctask == ctask)
+               conn->ctask = NULL;
+       /* release ref from queuecommand */
+       __iscsi_put_ctask(ctask);
+}
+
+/**
+ * iscsi_free_mgmt_task - return mgmt task back to pool
+ * @conn: iscsi connection
+ * @mtask: mtask
+ *
+ * Must be called with session lock.
+ */
+void iscsi_free_mgmt_task(struct iscsi_conn *conn,
+                         struct iscsi_mgmt_task *mtask)
+{
+       list_del_init(&mtask->running);
+       if (conn->login_mtask == mtask)
+               return;
+       __kfifo_put(conn->session->mgmtpool.queue,
+                   (void*)&mtask, sizeof(void*));
+}
+EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
+
 /**
  * iscsi_cmd_rsp - SCSI Command Response processing
  * @conn: iscsi connection
@@ -464,10 +508,7 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                         */
                        if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
                                rc = ISCSI_ERR_CONN_FAILED;
-                       list_del_init(&mtask->running);
-                       if (conn->login_mtask != mtask)
-                               __kfifo_put(session->mgmtpool.queue,
-                                           (void*)&mtask, sizeof(void*));
+                       iscsi_free_mgmt_task(conn, mtask);
                        break;
                case ISCSI_OP_SCSI_TMFUNC_RSP:
                        if (datalen) {
@@ -476,6 +517,7 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                        }
 
                        iscsi_tmf_rsp(conn, hdr);
+                       iscsi_free_mgmt_task(conn, mtask);
                        break;
                case ISCSI_OP_NOOP_IN:
                        if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
@@ -486,9 +528,7 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 
                        if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
                                rc = ISCSI_ERR_CONN_FAILED;
-                       list_del_init(&mtask->running);
-                       __kfifo_put(session->mgmtpool.queue,
-                                   (void*)&mtask, sizeof(void*));
+                       iscsi_free_mgmt_task(conn, mtask);
                        break;
                default:
                        rc = ISCSI_ERR_BAD_OPCODE;
@@ -650,14 +690,12 @@ static void iscsi_prep_mtask(struct iscsi_conn *conn,
 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 {
        struct iscsi_hdr *hdr = conn->mtask->hdr;
-       int rc, was_logout = 0;
+       int rc;
 
+       if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
+               conn->session->state = ISCSI_STATE_LOGGING_OUT;
        spin_unlock_bh(&conn->session->lock);
-       if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT) {
-               conn->session->state = ISCSI_STATE_IN_RECOVERY;
-               iscsi_block_session(session_to_cls(conn->session));
-               was_logout = 1;
-       }
+
        rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
        spin_lock_bh(&conn->session->lock);
        if (rc)
@@ -665,11 +703,6 @@ static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 
        /* done with this in-progress mtask */
        conn->mtask = NULL;
-
-       if (was_logout) {
-               set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
-               return -ENODATA;
-       }
        return 0;
 }
 
@@ -763,6 +796,12 @@ check_mgmt:
        while (!list_empty(&conn->mgmtqueue)) {
                conn->mtask = list_entry(conn->mgmtqueue.next,
                                         struct iscsi_mgmt_task, running);
+               if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
+                       iscsi_free_mgmt_task(conn, conn->mtask);
+                       conn->mtask = NULL;
+                       continue;
+               }
+
                iscsi_prep_mtask(conn, conn->mtask);
                list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
                rc = iscsi_xmit_mtask(conn);
@@ -777,6 +816,10 @@ check_mgmt:
 
                conn->ctask = list_entry(conn->xmitqueue.next,
                                         struct iscsi_cmd_task, running);
+               if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
+                       fail_command(conn, conn->ctask, DID_NO_CONNECT << 16);
+                       continue;
+               }
                if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
                        fail_command(conn, conn->ctask, DID_ABORT << 16);
                        continue;
@@ -800,6 +843,12 @@ check_mgmt:
                if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
                        break;
 
+               /*
+                * we always do fastlogout - conn stop code will clean up.
+                */
+               if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
+                       break;
+
                conn->ctask = list_entry(conn->requeue.next,
                                         struct iscsi_cmd_task, running);
                conn->ctask->state = ISCSI_TASK_RUNNING;
@@ -842,6 +891,7 @@ enum {
        FAILURE_SESSION_TERMINATE,
        FAILURE_SESSION_IN_RECOVERY,
        FAILURE_SESSION_RECOVERY_TIMEOUT,
+       FAILURE_SESSION_LOGGING_OUT,
 };
 
 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
@@ -879,12 +929,19 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
                        goto reject;
                }
 
-               if (session->state == ISCSI_STATE_RECOVERY_FAILED)
+               switch (session->state) {
+               case ISCSI_STATE_RECOVERY_FAILED:
                        reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
-               else if (session->state == ISCSI_STATE_TERMINATE)
+                       break;
+               case ISCSI_STATE_TERMINATE:
                        reason = FAILURE_SESSION_TERMINATE;
-               else
+                       break;
+               case ISCSI_STATE_LOGGING_OUT:
+                       reason = FAILURE_SESSION_LOGGING_OUT;
+                       break;
+               default:
                        reason = FAILURE_SESSION_FREED;
+               }
                goto fault;
        }
 
@@ -1120,44 +1177,9 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
        if (age != session->age ||
            session->state != ISCSI_STATE_LOGGED_IN)
                return -ENOTCONN;
-
-       if (!list_empty(&mtask->running)) {
-               list_del_init(&mtask->running);
-               __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
-                           sizeof(void*));
-       }
        return 0;
 }
 
-/*
- * session lock must be held
- */
-static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
-                        int err)
-{
-       struct scsi_cmnd *sc;
-
-       sc = ctask->sc;
-       if (!sc)
-               return;
-
-       if (ctask->state == ISCSI_TASK_PENDING)
-               /*
-                * cmd never made it to the xmit thread, so we should not count
-                * the cmd in the sequencing
-                */
-               conn->session->queued_cmdsn--;
-       else
-               conn->session->tt->cleanup_cmd_task(conn, ctask);
-
-       sc->result = err;
-       scsi_set_resid(sc, scsi_bufflen(sc));
-       if (conn->ctask == ctask)
-               conn->ctask = NULL;
-       /* release ref from queuecommand */
-       __iscsi_put_ctask(ctask);
-}
-
 /*
  * Fail commands. session lock held and recv side suspended and xmit
  * thread flushed
@@ -1837,22 +1859,13 @@ flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
        /* handle pending */
        list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
                debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
-               list_del_init(&mtask->running);
-               if (mtask == conn->login_mtask)
-                       continue;
-               __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
-                           sizeof(void*));
+               iscsi_free_mgmt_task(conn, mtask);
        }
 
        /* handle running */
        list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
                debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
-               list_del_init(&mtask->running);
-
-               if (mtask == conn->login_mtask)
-                       continue;
-               __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
-                          sizeof(void*));
+               iscsi_free_mgmt_task(conn, mtask);
        }
 
        conn->mtask = NULL;

diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index 4b3e3c15121a62bc0f99d7f0300aa8ce8cb2aecf..d68f74523f2e4656b790118d163ba94a355af7b0 100644 (file)
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -346,6 +346,8 @@ extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 extern int iscsi_verify_itt(struct iscsi_conn *, struct iscsi_hdr *,
                            uint32_t *);
 extern void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask);
+extern void iscsi_free_mgmt_task(struct iscsi_conn *conn,
+                                struct iscsi_mgmt_task *mtask);
 
 /*
  * generic helpers

diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index 7ff6199cbd55bef57c55b58b8c5a58f20a5d115a..b8d97bd20f6e3cf3f67e15e7e14d6290cbd990f0 100644 (file)
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -176,6 +176,7 @@ struct iscsi_cls_conn {
 #define ISCSI_STATE_TERMINATE          4
 #define ISCSI_STATE_IN_RECOVERY                5
 #define ISCSI_STATE_RECOVERY_FAILED    6
+#define ISCSI_STATE_LOGGING_OUT                7
 
 struct iscsi_cls_session {
        struct list_head sess_list;             /* item in session_list */