1 files changed, 109 insertions, 52 deletions

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 59908aead531..716cc344c5df 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -38,15 +38,30 @@
 #include <scsi/scsi_transport_iscsi.h>
 #include <scsi/libiscsi.h>
 
-static int iscsi_dbg_lib;
-module_param_named(debug_libiscsi, iscsi_dbg_lib, int, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(debug_libiscsi, "Turn on debugging for libiscsi module. "
-                 "Set to 1 to turn on, and zero to turn off. Default "
-                 "is off.");
+static int iscsi_dbg_lib_conn;
+module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
+                   S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug_libiscsi_conn,
+                 "Turn on debugging for connections in libiscsi module. "
+                 "Set to 1 to turn on, and zero to turn off. Default is off.");
+
+static int iscsi_dbg_lib_session;
+module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
+                   S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug_libiscsi_session,
+                 "Turn on debugging for sessions in libiscsi module. "
+                 "Set to 1 to turn on, and zero to turn off. Default is off.");
+
+static int iscsi_dbg_lib_eh;
+module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
+                   S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug_libiscsi_eh,
+                 "Turn on debugging for error handling in libiscsi module. "
+                 "Set to 1 to turn on, and zero to turn off. Default is off.");
 
 #define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...)                  \
         do {                                                    \
-                if (iscsi_dbg_lib)                              \
+                if (iscsi_dbg_lib_conn)                         \
                         iscsi_conn_printk(KERN_INFO, _conn,     \
                                              "%s " dbg_fmt,     \
                                              __func__, ##arg);  \
@@ -54,7 +69,15 @@ MODULE_PARM_DESC(debug_libiscsi, "Turn on debugging for libiscsi module. "
 
 #define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...)                    \
         do {                                                            \
-                if (iscsi_dbg_lib)                                      \
+                if (iscsi_dbg_lib_session)                              \
+                        iscsi_session_printk(KERN_INFO, _session,       \
+                                             "%s " dbg_fmt,             \
+                                             __func__, ##arg);          \
+        } while (0);
+
+#define ISCSI_DBG_EH(_session, dbg_fmt, arg...)                         \
+        do {                                                            \
+                if (iscsi_dbg_lib_eh)                                   \
                         iscsi_session_printk(KERN_INFO, _session,       \
                                              "%s " dbg_fmt,             \
                                              __func__, ##arg);          \
@@ -954,6 +977,7 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                 task = iscsi_itt_to_ctask(conn, hdr->itt);
                 if (!task)
                         return ISCSI_ERR_BAD_ITT;
+                task->last_xfer = jiffies;
                 break;
         case ISCSI_OP_R2T:
                 /*
@@ -1192,10 +1216,12 @@ static int iscsi_xmit_task(struct iscsi_conn *conn)
         spin_unlock_bh(&conn->session->lock);
         rc = conn->session->tt->xmit_task(task);
         spin_lock_bh(&conn->session->lock);
-        __iscsi_put_task(task);
-        if (!rc)
+        if (!rc) {
                 /* done with this task */
+                task->last_xfer = jiffies;
                 conn->task = NULL;
+        }
+        __iscsi_put_task(task);
         return rc;
 }
 
@@ -1361,6 +1387,9 @@ static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
         task->state = ISCSI_TASK_PENDING;
         task->conn = conn;
         task->sc = sc;
+        task->have_checked_conn = false;
+        task->last_timeout = jiffies;
+        task->last_xfer = jiffies;
         INIT_LIST_HEAD(&task->running);
         return task;
 }
@@ -1555,10 +1584,10 @@ int iscsi_eh_target_reset(struct scsi_cmnd *sc)
         spin_lock_bh(&session->lock);
         if (session->state == ISCSI_STATE_TERMINATE) {
 failed:
-                iscsi_session_printk(KERN_INFO, session,
-                                     "failing target reset: Could not log "
-                                     "back into target [age %d]\n",
-                                     session->age);
+                ISCSI_DBG_EH(session,
+                             "failing target reset: Could not log back into "
+                             "target [age %d]\n",
+                             session->age);
                 spin_unlock_bh(&session->lock);
                 mutex_unlock(&session->eh_mutex);
                 return FAILED;
@@ -1572,7 +1601,7 @@ failed:
          */
         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 
-        ISCSI_DBG_SESSION(session, "wait for relogin\n");
+        ISCSI_DBG_EH(session, "wait for relogin\n");
         wait_event_interruptible(conn->ehwait,
                                  session->state == ISCSI_STATE_TERMINATE ||
                                  session->state == ISCSI_STATE_LOGGED_IN ||
@@ -1582,10 +1611,10 @@ failed:
 
         mutex_lock(&session->eh_mutex);
         spin_lock_bh(&session->lock);
-        if (session->state == ISCSI_STATE_LOGGED_IN)
-                iscsi_session_printk(KERN_INFO, session,
-                                     "target reset succeeded\n");
-        else
+        if (session->state == ISCSI_STATE_LOGGED_IN) {
+                ISCSI_DBG_EH(session,
+                             "target reset succeeded\n");
+        } else
                 goto failed;
         spin_unlock_bh(&session->lock);
         mutex_unlock(&session->eh_mutex);
@@ -1601,7 +1630,7 @@ static void iscsi_tmf_timedout(unsigned long data)
         spin_lock(&session->lock);
         if (conn->tmf_state == TMF_QUEUED) {
                 conn->tmf_state = TMF_TIMEDOUT;
-                ISCSI_DBG_SESSION(session, "tmf timedout\n");
+                ISCSI_DBG_EH(session, "tmf timedout\n");
                 /* unblock eh_abort() */
                 wake_up(&conn->ehwait);
         }
@@ -1621,7 +1650,7 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
                 spin_unlock_bh(&session->lock);
                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
                 spin_lock_bh(&session->lock);
-                ISCSI_DBG_SESSION(session, "tmf exec failure\n");
+                ISCSI_DBG_EH(session, "tmf exec failure\n");
                 return -EPERM;
         }
         conn->tmfcmd_pdus_cnt++;
@@ -1629,7 +1658,7 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
         conn->tmf_timer.function = iscsi_tmf_timedout;
         conn->tmf_timer.data = (unsigned long)conn;
         add_timer(&conn->tmf_timer);
-        ISCSI_DBG_SESSION(session, "tmf set timeout\n");
+        ISCSI_DBG_EH(session, "tmf set timeout\n");
 
         spin_unlock_bh(&session->lock);
         mutex_unlock(&session->eh_mutex);
@@ -1716,17 +1745,18 @@ static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
                 return 0;
 }
 
-static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
+static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
 {
+        enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
+        struct iscsi_task *task = NULL;
         struct iscsi_cls_session *cls_session;
         struct iscsi_session *session;
         struct iscsi_conn *conn;
-        enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
 
-        cls_session = starget_to_session(scsi_target(scmd->device));
+        cls_session = starget_to_session(scsi_target(sc->device));
         session = cls_session->dd_data;
 
-        ISCSI_DBG_SESSION(session, "scsi cmd %p timedout\n", scmd);
+        ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
 
         spin_lock(&session->lock);
         if (session->state != ISCSI_STATE_LOGGED_IN) {
@@ -1745,6 +1775,26 @@ static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
                 goto done;
         }
 
+        task = (struct iscsi_task *)sc->SCp.ptr;
+        if (!task)
+                goto done;
+        /*
+         * If we have sent (at least queued to the network layer) a pdu or
+         * recvd one for the task since the last timeout ask for
+         * more time. If on the next timeout we have not made progress
+         * we can check if it is the task or connection when we send the
+         * nop as a ping.
+         */
+        if (time_after_eq(task->last_xfer, task->last_timeout)) {
+                ISCSI_DBG_EH(session, "Command making progress. Asking "
+                             "scsi-ml for more time to complete. "
+                             "Last data recv at %lu. Last timeout was at "
+                             "%lu\n.", task->last_xfer, task->last_timeout);
+                task->have_checked_conn = false;
+                rc = BLK_EH_RESET_TIMER;
+                goto done;
+        }
+
         if (!conn->recv_timeout && !conn->ping_timeout)
                 goto done;
         /*
@@ -1755,23 +1805,32 @@ static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
                 rc = BLK_EH_RESET_TIMER;
                 goto done;
         }
+
+        /* Assumes nop timeout is shorter than scsi cmd timeout */
+        if (task->have_checked_conn)
+                goto done;
+
         /*
-         * if we are about to check the transport then give the command
-         * more time
+         * Checking the transport already or nop from a cmd timeout still
+         * running
          */
-        if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
-                           jiffies)) {
+        if (conn->ping_task) {
+                task->have_checked_conn = true;
                 rc = BLK_EH_RESET_TIMER;
                 goto done;
         }
 
-        /* if in the middle of checking the transport then give us more time */
-        if (conn->ping_task)
-                rc = BLK_EH_RESET_TIMER;
+        /* Make sure there is a transport check done */
+        iscsi_send_nopout(conn, NULL);
+        task->have_checked_conn = true;
+        rc = BLK_EH_RESET_TIMER;
+
 done:
+        if (task)
+                task->last_timeout = jiffies;
         spin_unlock(&session->lock);
-        ISCSI_DBG_SESSION(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
-                          "timer reset" : "nh");
+        ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
+                     "timer reset" : "nh");
         return rc;
 }
 
@@ -1841,7 +1900,7 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
         cls_session = starget_to_session(scsi_target(sc->device));
         session = cls_session->dd_data;
 
-        ISCSI_DBG_SESSION(session, "aborting sc %p\n", sc);
+        ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
 
         mutex_lock(&session->eh_mutex);
         spin_lock_bh(&session->lock);
@@ -1850,8 +1909,8 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
          * got the command.
          */
         if (!sc->SCp.ptr) {
-                ISCSI_DBG_SESSION(session, "sc never reached iscsi layer or "
-                                  "it completed.\n");
+                ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
+                                      "it completed.\n");
                 spin_unlock_bh(&session->lock);
                 mutex_unlock(&session->eh_mutex);
                 return SUCCESS;
@@ -1865,7 +1924,7 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
             sc->SCp.phase != session->age) {
                 spin_unlock_bh(&session->lock);
                 mutex_unlock(&session->eh_mutex);
-                ISCSI_DBG_SESSION(session, "failing abort due to dropped "
+                ISCSI_DBG_EH(session, "failing abort due to dropped "
                                   "session.\n");
                 return FAILED;
         }
@@ -1875,13 +1934,12 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
         age = session->age;
 
         task = (struct iscsi_task *)sc->SCp.ptr;
-        ISCSI_DBG_SESSION(session, "aborting [sc %p itt 0x%x]\n",
-                          sc, task->itt);
+        ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
+                     sc, task->itt);
 
         /* task completed before time out */
         if (!task->sc) {
-                ISCSI_DBG_SESSION(session, "sc completed while abort in "
-                                  "progress\n");
+                ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
                 goto success;
         }
 
@@ -1930,8 +1988,8 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
                 if (!sc->SCp.ptr) {
                         conn->tmf_state = TMF_INITIAL;
                         /* task completed before tmf abort response */
-                        ISCSI_DBG_SESSION(session, "sc completed while abort "
-                                          "in progress\n");
+                        ISCSI_DBG_EH(session, "sc completed while abort in "
+                                              "progress\n");
                         goto success;
                 }
                 /* fall through */
@@ -1943,16 +2001,16 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
 success:
         spin_unlock_bh(&session->lock);
 success_unlocked:
-        ISCSI_DBG_SESSION(session, "abort success [sc %p itt 0x%x]\n",
-                          sc, task->itt);
+        ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
+                     sc, task->itt);
         mutex_unlock(&session->eh_mutex);
         return SUCCESS;
 
 failed:
         spin_unlock_bh(&session->lock);
 failed_unlocked:
-        ISCSI_DBG_SESSION(session, "abort failed [sc %p itt 0x%x]\n", sc,
-                          task ? task->itt : 0);
+        ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
+                     task ? task->itt : 0);
         mutex_unlock(&session->eh_mutex);
         return FAILED;
 }
@@ -1979,8 +2037,7 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
         cls_session = starget_to_session(scsi_target(sc->device));
         session = cls_session->dd_data;
 
-        ISCSI_DBG_SESSION(session, "LU Reset [sc %p lun %u]\n",
-                          sc, sc->device->lun);
+        ISCSI_DBG_EH(session, "LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
 
         mutex_lock(&session->eh_mutex);
         spin_lock_bh(&session->lock);
@@ -2034,8 +2091,8 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
 unlock:
         spin_unlock_bh(&session->lock);
 done:
-        ISCSI_DBG_SESSION(session, "dev reset result = %s\n",
-                         rc == SUCCESS ? "SUCCESS" : "FAILED");
+        ISCSI_DBG_EH(session, "dev reset result = %s\n",
+                     rc == SUCCESS ? "SUCCESS" : "FAILED");
         mutex_unlock(&session->eh_mutex);
         return rc;
 }