3 files changed, 68 insertions, 77 deletions

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 88dafdf45c47..ab324d984b8d 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -185,11 +185,19 @@ iscsi_hdr_extract(struct iscsi_tcp_conn *tcp_conn)
  * must be called with session lock
  */
 static void
-__iscsi_ctask_cleanup(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 {
         struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
+        struct iscsi_r2t_info *r2t;
         struct scsi_cmnd *sc;
 
+        /* flush ctask's r2t queues */
+        while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
+                __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
+                            sizeof(void*));
+                debug_scsi("iscsi_tcp_cleanup_ctask pending r2t dropped\n");
+        }
+
         sc = ctask->sc;
         if (unlikely(!sc))
                 return;
@@ -374,6 +382,7 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
                 spin_unlock(&session->lock);
                 return 0;
         }
+
         rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
         BUG_ON(!rc);
 
@@ -399,7 +408,7 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
         tcp_ctask->exp_r2tsn = r2tsn + 1;
         tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
         __kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
-        __kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
+        list_move_tail(&ctask->running, &conn->xmitqueue);
 
         scsi_queue_work(session->host, &conn->xmitwork);
         conn->r2t_pdus_cnt++;
@@ -484,7 +493,7 @@ iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
                         goto copy_hdr;
 
                 spin_lock(&session->lock);
-                __iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
+                iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
                 rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
                 spin_unlock(&session->lock);
                 break;
@@ -745,10 +754,11 @@ static int iscsi_scsi_data_in(struct iscsi_conn *conn)
 done:
         /* check for non-exceptional status */
         if (tcp_conn->in.hdr->flags & ISCSI_FLAG_DATA_STATUS) {
-                debug_scsi("done [sc %lx res %d itt 0x%x]\n",
-                           (long)sc, sc->result, ctask->itt);
+                debug_scsi("done [sc %lx res %d itt 0x%x flags 0x%x]\n",
+                           (long)sc, sc->result, ctask->itt,
+                           tcp_conn->in.hdr->flags);
                 spin_lock(&conn->session->lock);
-                __iscsi_ctask_cleanup(conn, ctask);
+                iscsi_tcp_cleanup_ctask(conn, ctask);
                 __iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
                 spin_unlock(&conn->session->lock);
         }
@@ -769,7 +779,7 @@ iscsi_data_recv(struct iscsi_conn *conn)
                 break;
         case ISCSI_OP_SCSI_CMD_RSP:
                 spin_lock(&conn->session->lock);
-                __iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
+                iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
                 spin_unlock(&conn->session->lock);
         case ISCSI_OP_TEXT_RSP:
         case ISCSI_OP_LOGIN_RSP:
@@ -1308,7 +1318,7 @@ iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
                                     ctask->imm_count -
                                     ctask->unsol_count;
 
-                debug_scsi("cmd [itt %x total %d imm %d imm_data %d "
+                debug_scsi("cmd [itt 0x%x total %d imm %d imm_data %d "
                            "r2t_data %d]\n",
                            ctask->itt, ctask->total_length, ctask->imm_count,
                            ctask->unsol_count, tcp_ctask->r2t_data_count);
@@ -1636,7 +1646,7 @@ handle_xmstate_sol_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
         }
 solicit_again:
         /*
-         * send Data-Out whitnin this R2T sequence.
+         * send Data-Out within this R2T sequence.
          */
         if (!r2t->data_count)
                 goto data_out_done;
@@ -1731,7 +1741,7 @@ handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
         struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
         struct iscsi_data_task *dtask = tcp_ctask->dtask;
-        int sent, rc;
+        int sent = 0, rc;
 
         tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
         iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
@@ -2002,20 +2012,6 @@ iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
 }
 
 static void
-iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
-        struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-        struct iscsi_r2t_info *r2t;
-
-        /* flush ctask's r2t queues */
-        while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*)))
-                __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
-                            sizeof(void*));
-
-        __iscsi_ctask_cleanup(conn, ctask);
-}
-
-static void
 iscsi_tcp_suspend_conn_rx(struct iscsi_conn *conn)
 {
         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
@@ -2057,6 +2053,7 @@ iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask,
         iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
                            sizeof(struct iscsi_hdr));
         tcp_mtask->xmstate = XMSTATE_IMM_HDR;
+        tcp_mtask->sent = 0;
 
         if (mtask->data_count)
                 iscsi_buf_init_iov(&tcp_mtask->sendbuf, (char*)mtask->data,
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 7e6e031cc41b..1a8cd20f484f 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -189,6 +189,7 @@ static void iscsi_complete_command(struct iscsi_session *session,
 {
         struct scsi_cmnd *sc = ctask->sc;
 
+        ctask->state = ISCSI_TASK_COMPLETED;
         ctask->sc = NULL;
         list_del_init(&ctask->running);
         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
@@ -568,20 +569,24 @@ static int iscsi_data_xmit(struct iscsi_conn *conn)
         }
 
         /* process command queue */
-        while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
-                           sizeof(void*))) {
+        spin_lock_bh(&conn->session->lock);
+        while (!list_empty(&conn->xmitqueue)) {
                 /*
                  * iscsi tcp may readd the task to the xmitqueue to send
                  * write data
                  */
-                spin_lock_bh(&conn->session->lock);
-                if (list_empty(&conn->ctask->running))
-                        list_add_tail(&conn->ctask->running, &conn->run_list);
+                conn->ctask = list_entry(conn->xmitqueue.next,
+                                         struct iscsi_cmd_task, running);
+                conn->ctask->state = ISCSI_TASK_RUNNING;
+                list_move_tail(conn->xmitqueue.next, &conn->run_list);
                 spin_unlock_bh(&conn->session->lock);
+
                 rc = tt->xmit_cmd_task(conn, conn->ctask);
                 if (rc)
                         goto again;
+                spin_lock_bh(&conn->session->lock);
         }
+        spin_unlock_bh(&conn->session->lock);
         /* done with this ctask */
         conn->ctask = NULL;
 
@@ -691,6 +696,7 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
         sc->SCp.phase = session->age;
         sc->SCp.ptr = (char *)ctask;
 
+        ctask->state = ISCSI_TASK_PENDING;
         ctask->mtask = NULL;
         ctask->conn = conn;
         ctask->sc = sc;
@@ -700,7 +706,7 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 
         session->tt->init_cmd_task(ctask);
 
-        __kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
+        list_add_tail(&ctask->running, &conn->xmitqueue);
         debug_scsi(
                "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
@@ -977,31 +983,27 @@ static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
 /*
  * xmit mutex and session lock must be held
  */
-#define iscsi_remove_task(tasktype)                                     \
-static struct iscsi_##tasktype *                                        \
-iscsi_remove_##tasktype(struct kfifo *fifo, uint32_t itt)               \
-{                                                                       \
-        int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);            \
-        struct iscsi_##tasktype *task;                                  \
-                                                                        \
-        debug_scsi("searching %d tasks\n", nr_tasks);                   \
-                                                                        \
-        for (i = 0; i < nr_tasks; i++) {                                \
-                __kfifo_get(fifo, (void*)&task, sizeof(void*));         \
-                debug_scsi("check task %u\n", task->itt);               \
-                                                                        \
-                if (task->itt == itt) {                                 \
-                        debug_scsi("matched task\n");                   \
-                        return task;                                    \
-                }                                                       \
-                                                                        \
-                __kfifo_put(fifo, (void*)&task, sizeof(void*));         \
-        }                                                               \
-        return NULL;                                                    \
-}
+static struct iscsi_mgmt_task *
+iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
+{
+        int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
+        struct iscsi_mgmt_task *task;
+
+        debug_scsi("searching %d tasks\n", nr_tasks);
+
+        for (i = 0; i < nr_tasks; i++) {
+                __kfifo_get(fifo, (void*)&task, sizeof(void*));
+                debug_scsi("check task %u\n", task->itt);
+
+                if (task->itt == itt) {
+                        debug_scsi("matched task\n");
+                        return task;
+                }
 
-iscsi_remove_task(mgmt_task);
-iscsi_remove_task(cmd_task);
+                __kfifo_put(fifo, (void*)&task, sizeof(void*));
+        }
+        return NULL;
+}
 
 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
 {
@@ -1043,7 +1045,6 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
         struct iscsi_conn *conn = ctask->conn;
         struct iscsi_session *session = conn->session;
-        struct iscsi_cmd_task *pending_ctask;
         int rc;
 
         conn->eh_abort_cnt++;
@@ -1071,17 +1072,8 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
                 goto failed;
         }
 
-        /* check for the easy pending cmd abort */
-        pending_ctask = iscsi_remove_cmd_task(conn->xmitqueue, ctask->itt);
-        if (pending_ctask) {
-                /* iscsi_tcp queues write transfers on the xmitqueue */
-                if (list_empty(&pending_ctask->running)) {
-                        debug_scsi("found pending task\n");
-                        goto success;
-                } else
-                        __kfifo_put(conn->xmitqueue, (void*)&pending_ctask,
-                                    sizeof(void*));
-        }
+        if (ctask->state == ISCSI_TASK_PENDING)
+                goto success;
 
         conn->tmabort_state = TMABORT_INITIAL;
 
@@ -1263,6 +1255,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit,
                 if (cmd_task_size)
                         ctask->dd_data = &ctask[1];
                 ctask->itt = cmd_i;
+                INIT_LIST_HEAD(&ctask->running);
         }
 
         spin_lock_init(&session->lock);
@@ -1282,6 +1275,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit,
                 if (mgmt_task_size)
                         mtask->dd_data = &mtask[1];
                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
+                INIT_LIST_HEAD(&mtask->running);
         }
 
         if (scsi_add_host(shost, NULL))
@@ -1361,12 +1355,7 @@ iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
         conn->tmabort_state = TMABORT_INITIAL;
         INIT_LIST_HEAD(&conn->run_list);
         INIT_LIST_HEAD(&conn->mgmt_run_list);
-
-        /* initialize general xmit PDU commands queue */
-        conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*),
-                                        GFP_KERNEL, NULL);
-        if (conn->xmitqueue == ERR_PTR(-ENOMEM))
-                goto xmitqueue_alloc_fail;
+        INIT_LIST_HEAD(&conn->xmitqueue);
 
         /* initialize general immediate & non-immediate PDU commands queue */
         conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
@@ -1410,8 +1399,6 @@ login_mtask_alloc_fail:
 mgmtqueue_alloc_fail:
         kfifo_free(conn->immqueue);
 immqueue_alloc_fail:
-        kfifo_free(conn->xmitqueue);
-xmitqueue_alloc_fail:
         iscsi_destroy_conn(cls_conn);
         return NULL;
 }
@@ -1489,7 +1476,6 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
                 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
         spin_unlock_bh(&session->lock);
 
-        kfifo_free(conn->xmitqueue);
         kfifo_free(conn->immqueue);
         kfifo_free(conn->mgmtqueue);
 
@@ -1572,7 +1558,7 @@ static void fail_all_commands(struct iscsi_conn *conn)
         struct iscsi_cmd_task *ctask, *tmp;
 
         /* flush pending */
-        while (__kfifo_get(conn->xmitqueue, (void*)&ctask, sizeof(void*))) {
+        list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
                 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
                            ctask->itt);
                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index ba2760802ded..e71d6e96eca6 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -83,6 +83,12 @@ struct iscsi_mgmt_task {
         struct list_head        running;
 };
 
+enum {
+        ISCSI_TASK_COMPLETED,
+        ISCSI_TASK_PENDING,
+        ISCSI_TASK_RUNNING,
+};
+
 struct iscsi_cmd_task {
         /*
          * Becuae LLDs allocate their hdr differently, this is a pointer to
@@ -101,6 +107,8 @@ struct iscsi_cmd_task {
         struct iscsi_conn       *conn;          /* used connection    */
         struct iscsi_mgmt_task  *mtask;         /* tmf mtask in progr */
 
+        /* state set/tested under session->lock */
+        int                     state;
         struct list_head        running;        /* running cmd list */
         void                    *dd_data;       /* driver/transport data */
 };
@@ -134,7 +142,7 @@ struct iscsi_conn {
         struct kfifo            *immqueue;      /* immediate xmit queue */
         struct kfifo            *mgmtqueue;     /* mgmt (control) xmit queue */
         struct list_head        mgmt_run_list;  /* list of control tasks */
-        struct kfifo            *xmitqueue;     /* data-path cmd queue */
+        struct list_head        xmitqueue;      /* data-path cmd queue */
         struct list_head        run_list;       /* list of cmds in progress */
         struct work_struct      xmitwork;       /* per-conn. xmit workqueue */
         /*