From c66d1cc62ac47b58931afc62bfdedd285fb315f0 Mon Sep 17 00:00:00 2001
From: Florian Pose <fp@igh.de>
Date: Tue, 25 Nov 2008 14:07:19 +0000
Subject: [PATCH] merge -r1583:1593 branches/stable-1.4: Fixed detaching oops.

---
 NEWS                                    |  2 +
 documentation/graphs/fsm_slave_conf.dot |  8 +++-
 master/fsm_pdo.c                        |  5 ++
 master/fsm_slave_config.c               | 62 ++++++++++++++++++++++---
 master/fsm_slave_config.h               |  1 +
 master/sdo_request.c                    | 16 +++++++
 master/sdo_request.h                    |  1 +
 7 files changed, 88 insertions(+), 7 deletions(-)

diff --git a/NEWS b/NEWS
index c261014c..267305ba 100644
--- a/NEWS
+++ b/NEWS
@@ -23,6 +23,8 @@ Changes since 1.4.0-rc3:
 * Fixed race condition concerning the ec_slave_config_state->operational flag.
 * Fixed wrong calculation of the expected working counter if the process data
   of a domain span several datagrams.
+* Fixed a kernel oops when a slave configuration is detached while the actual
+  configuration is in progress.
 * Fixed typo in logging output.
 
 Changes in 1.4.0-rc3:
diff --git a/documentation/graphs/fsm_slave_conf.dot b/documentation/graphs/fsm_slave_conf.dot
index d7ee382f..8ed4a345 100644
--- a/documentation/graphs/fsm_slave_conf.dot
+++ b/documentation/graphs/fsm_slave_conf.dot
@@ -5,7 +5,10 @@ digraph slaveconf {
     size="3,5"
 
     start [fontname="Helvetica"]
-    start -> init [weight=10]
+    start -> enter_init [weight=10]
+
+    enter_init [shape=point, label=""]
+    enter_init -> init [weight=10]
 
     init [fontname="Helvetica"]
     init -> enter_mbox_sync [fontname="Helvetica", label="No FMMUs"]
@@ -32,12 +35,14 @@ digraph slaveconf {
     enter_sdo_conf -> sdo_conf [weight=10]
 
     sdo_conf [fontname="Helvetica"]
+    sdo_conf -> enter_init [fontname="Helvetica", label="Config\ndetached"]
     sdo_conf -> enter_pdo_conf [weight=10]
 
     enter_pdo_conf [shape=point, label=""]
     enter_pdo_conf -> pdo_conf [weight=10]
 
     pdo_conf [fontname="Helvetica"]
+    pdo_conf -> enter_init [fontname="Helvetica", label="Config\ndetached"]
     pdo_conf -> enter_pdo_sync [weight=10]
 
     enter_pdo_sync [shape=point, label=""]
@@ -45,6 +50,7 @@ digraph slaveconf {
     enter_pdo_sync -> pdo_sync [weight=10]
 
     pdo_sync [fontname="Helvetica"]
+    pdo_sync -> enter_init [fontname="Helvetica", label="Config\ndetached"]
     pdo_sync -> enter_fmmu [weight=10]
 
     enter_fmmu [shape=point,label=""]
diff --git a/master/fsm_pdo.c b/master/fsm_pdo.c
index f7cd5a82..08b03bc5 100644
--- a/master/fsm_pdo.c
+++ b/master/fsm_pdo.c
@@ -402,6 +402,11 @@ void ec_fsm_pdo_conf_action_next_sync(
     fsm->sync_index++;
 
     for (; fsm->sync_index < EC_MAX_SYNC_MANAGERS; fsm->sync_index++) {
+        if (!fsm->slave->config) { // slave configuration removed in the meantime
+            fsm->state = ec_fsm_pdo_state_error;
+            return;
+        }
+
         if (ec_pdo_list_copy(&fsm->pdos,
                     &fsm->slave->config->sync_configs[fsm->sync_index].pdos)) {
             fsm->state = ec_fsm_pdo_state_error;
diff --git a/master/fsm_slave_config.c b/master/fsm_slave_config.c
index 73936246..5bba210b 100644
--- a/master/fsm_slave_config.c
+++ b/master/fsm_slave_config.c
@@ -58,6 +58,7 @@ void ec_fsm_slave_config_state_fmmu(ec_fsm_slave_config_t *);
 void ec_fsm_slave_config_state_safeop(ec_fsm_slave_config_t *);
 void ec_fsm_slave_config_state_op(ec_fsm_slave_config_t *);
 
+void ec_fsm_slave_config_enter_init(ec_fsm_slave_config_t *);
 void ec_fsm_slave_config_enter_mbox_sync(ec_fsm_slave_config_t *);
 void ec_fsm_slave_config_enter_preop(ec_fsm_slave_config_t *);
 void ec_fsm_slave_config_enter_sdo_conf(ec_fsm_slave_config_t *);
@@ -69,6 +70,8 @@ void ec_fsm_slave_config_enter_safeop(ec_fsm_slave_config_t *);
 void ec_fsm_slave_config_state_end(ec_fsm_slave_config_t *);
 void ec_fsm_slave_config_state_error(ec_fsm_slave_config_t *);
 
+void ec_fsm_slave_config_reconfigure(ec_fsm_slave_config_t *);
+
 /*****************************************************************************/
 
 /** Constructor.
@@ -81,6 +84,8 @@ void ec_fsm_slave_config_init(
         ec_fsm_pdo_t *fsm_pdo /**< Pdo configuration state machine to use. */
         )
 {
+    ec_sdo_request_init(&fsm->request_copy);
+
     fsm->datagram = datagram;
     fsm->fsm_change = fsm_change;
     fsm->fsm_coe = fsm_coe;
@@ -95,6 +100,7 @@ void ec_fsm_slave_config_clear(
         ec_fsm_slave_config_t *fsm /**< slave state machine */
         )
 {
+    ec_sdo_request_clear(&fsm->request_copy);
 }
 
 /*****************************************************************************/
@@ -172,6 +178,17 @@ void ec_fsm_slave_config_state_start(
         EC_DBG("Configuring slave %u...\n", fsm->slave->ring_position);
     }
     
+    ec_fsm_slave_config_enter_init(fsm);
+}
+
+/*****************************************************************************/
+
+/** Start state change to INIT.
+ */
+void ec_fsm_slave_config_enter_init(
+        ec_fsm_slave_config_t *fsm /**< slave state machine */
+        )
+{
     ec_fsm_change_start(fsm->fsm_change, fsm->slave, EC_SLAVE_STATE_INIT);
     ec_fsm_change_exec(fsm->fsm_change);
     fsm->state = ec_fsm_slave_config_state_init;
@@ -444,8 +461,9 @@ void ec_fsm_slave_config_enter_sdo_conf(
     fsm->state = ec_fsm_slave_config_state_sdo_conf;
     fsm->request = list_entry(fsm->slave->config->sdo_configs.next,
             ec_sdo_request_t, list);
-    ecrt_sdo_request_write(fsm->request);
-    ec_fsm_coe_transfer(fsm->fsm_coe, fsm->slave, fsm->request);
+    ec_sdo_request_copy(&fsm->request_copy, fsm->request);
+    ecrt_sdo_request_write(&fsm->request_copy);
+    ec_fsm_coe_transfer(fsm->fsm_coe, fsm->slave, &fsm->request_copy);
     ec_fsm_coe_exec(fsm->fsm_coe); // execute immediately
 }
 
@@ -467,12 +485,18 @@ void ec_fsm_slave_config_state_sdo_conf(
         return;
     }
 
+    if (!fsm->slave->config) { // config removed in the meantime
+        ec_fsm_slave_config_reconfigure(fsm);
+        return;
+    }
+
     // Another Sdo to configure?
     if (fsm->request->list.next != &fsm->slave->config->sdo_configs) {
-        fsm->request = list_entry(fsm->request->list.next, ec_sdo_request_t,
-                list);
-        ecrt_sdo_request_write(fsm->request);
-        ec_fsm_coe_transfer(fsm->fsm_coe, fsm->slave, fsm->request);
+        fsm->request = list_entry(fsm->request->list.next,
+                ec_sdo_request_t, list);
+        ec_sdo_request_copy(&fsm->request_copy, fsm->request);
+        ecrt_sdo_request_write(&fsm->request_copy);
+        ec_fsm_coe_transfer(fsm->fsm_coe, fsm->slave, &fsm->request_copy);
         ec_fsm_coe_exec(fsm->fsm_coe); // execute immediately
         return;
     }
@@ -506,6 +530,11 @@ void ec_fsm_slave_config_state_pdo_conf(
     if (ec_fsm_pdo_exec(fsm->fsm_pdo))
         return;
 
+    if (!fsm->slave->config) { // config removed in the meantime
+        ec_fsm_slave_config_reconfigure(fsm);
+        return;
+    }
+
     if (!ec_fsm_pdo_success(fsm->fsm_pdo)) {
         EC_WARN("Pdo configuration failed on slave %u.\n",
                 fsm->slave->ring_position);
@@ -594,6 +623,11 @@ void ec_fsm_slave_config_state_pdo_sync(
         return;
     }
 
+    if (!fsm->slave->config) { // config removed in the meantime
+        ec_fsm_slave_config_reconfigure(fsm);
+        return;
+    }
+
     ec_fsm_slave_config_enter_fmmu(fsm);
 }
 
@@ -764,6 +798,22 @@ void ec_fsm_slave_config_state_op(
     fsm->state = ec_fsm_slave_config_state_end; // successful
 }
 
+/*****************************************************************************/
+
+/** Reconfigure the slave starting at INIT.
+ */
+void ec_fsm_slave_config_reconfigure(
+        ec_fsm_slave_config_t *fsm /**< slave state machine */
+        )
+{
+    if (fsm->slave->master->debug_level) {
+        EC_DBG("Slave configuration for slave %u detached during "
+                "configuration. Reconfiguring.", fsm->slave->ring_position);
+    }
+
+    ec_fsm_slave_config_enter_init(fsm); // reconfigure
+}
+
 /******************************************************************************
  *  Common state functions
  *****************************************************************************/
diff --git a/master/fsm_slave_config.h b/master/fsm_slave_config.h
index ddf37876..d03417aa 100644
--- a/master/fsm_slave_config.h
+++ b/master/fsm_slave_config.h
@@ -66,6 +66,7 @@ struct ec_fsm_slave_config
     void (*state)(ec_fsm_slave_config_t *); /**< State function. */
     unsigned int retries; /**< Retries on datagram timeout. */
     ec_sdo_request_t *request; /**< Sdo request for Sdo configuration. */
+    ec_sdo_request_t request_copy; /**< Copied Sdo request. */
 };
 
 /*****************************************************************************/
diff --git a/master/sdo_request.c b/master/sdo_request.c
index 5b417ec8..e23a7a3c 100644
--- a/master/sdo_request.c
+++ b/master/sdo_request.c
@@ -83,6 +83,22 @@ void ec_sdo_request_clear(
 
 /*****************************************************************************/
 
+/** Copy another Sdo request.
+ *
+ * \attention Only the index subindex and data are copied.
+ */
+int ec_sdo_request_copy(
+        ec_sdo_request_t *req,
+        const ec_sdo_request_t *other
+        )
+{
+    req->index = other->index;
+    req->subindex = other->subindex;
+    return ec_sdo_request_copy_data(req, other->data, other->data_size);
+}
+
+/*****************************************************************************/
+
 /** Sdo request destructor.
  */
 void ec_sdo_request_clear_data(
diff --git a/master/sdo_request.h b/master/sdo_request.h
index ee96ab5a..69ae7367 100644
--- a/master/sdo_request.h
+++ b/master/sdo_request.h
@@ -75,6 +75,7 @@ struct ec_sdo_request {
 void ec_sdo_request_init(ec_sdo_request_t *);
 void ec_sdo_request_clear(ec_sdo_request_t *);
 
+int ec_sdo_request_copy(ec_sdo_request_t *, const ec_sdo_request_t *);
 void ec_sdo_request_address(ec_sdo_request_t *, uint16_t, uint8_t);
 int ec_sdo_request_alloc(ec_sdo_request_t *, size_t);
 int ec_sdo_request_copy_data(ec_sdo_request_t *, const uint8_t *, size_t);