Changeset 3fb5a3e in mainline

Timestamp:

2011-05-28T14:34:43Z (13 years ago)

Author:

Vojtech Horky <vojtechhorky@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

af6136d

Parents:

400735e

Message:

Do not delete hub info too early

When a hub is disconnected during port change (device adding) the
structure was deleted and accessed *later* from the device adding
routine. Because allocator is next fit, the error went unnoticed.

Location:

uspace/drv/usbhub

Files:

• ports.c (modified) (2 diffs)
• usbhub.c (modified) (4 diffs)
• usbhub.h (modified) (1 diff)

uspace/drv/usbhub/ports.c

@@ -407 +407 @@
         free(arg);
 
+        fibril_mutex_lock(&data->hub->pending_ops_mutex);
+        assert(data->hub->pending_ops_count > 0);
+        data->hub->pending_ops_count--;
+        fibril_condvar_signal(&data->hub->pending_ops_cv);
+        fibril_mutex_unlock(&data->hub->pending_ops_mutex);
+
+
         return EOK;
 }
@@ -452 +459 @@
                 return ENOMEM;
         }
+        fibril_mutex_lock(&hub->pending_ops_mutex);
+        hub->pending_ops_count++;
+        fibril_mutex_unlock(&hub->pending_ops_mutex);
         fibril_add_ready(fibril);
 

uspace/drv/usbhub/usbhub.c

@@ -72 +72 @@
 static void usb_hub_process_global_interrupt(usb_hub_info_t * hub_info);
 
-static void usb_hub_polling_terminted_callback(usb_device_t * device,
+static void usb_hub_polling_terminated_callback(usb_device_t * device,
     bool was_error, void * data);
 
@@ -200 +200 @@
         result->control_pipe = &usb_dev->ctrl_pipe;
         result->is_default_address_used = false;
+
+        fibril_mutex_initialize(&result->pending_ops_mutex);
+        fibril_condvar_initialize(&result->pending_ops_cv);
+        result->pending_ops_count = 0;
         return result;
 }
@@ -340 +344 @@
         rc = usb_device_auto_poll(hub_info->usb_device, 0,
             hub_port_changes_callback, ((hub_info->port_count + 1) / 8) + 1,
-            usb_hub_polling_terminted_callback, hub_info);
+            usb_hub_polling_terminated_callback, hub_info);
         if (rc != EOK) {
                 usb_log_error("Failed to create polling fibril: %s.\n",
@@ -473 +477 @@
  * @param data pointer to usb_hub_info_t structure
  */
-static void usb_hub_polling_terminted_callback(usb_device_t * device,
+static void usb_hub_polling_terminated_callback(usb_device_t * device,
     bool was_error, void * data){
-        usb_hub_info_t * hub_info = data;
-        if(!hub_info) return;
-        free(hub_info->ports);
-        free(hub_info);
+        usb_hub_info_t * hub = data;
+        assert(hub);
+
+        fibril_mutex_lock(&hub->pending_ops_mutex);
+        while (hub->pending_ops_count > 0) {
+                fibril_condvar_wait(&hub->pending_ops_cv,
+                    &hub->pending_ops_mutex);
+        }
+        fibril_mutex_unlock(&hub->pending_ops_mutex);
+
+        free(hub->ports);
+        free(hub);
 }
 

uspace/drv/usbhub/usbhub.h

@@ -89 +89 @@
         /** generic usb device data*/
         usb_device_t * usb_device;
+
+        /** Number of pending operations on the mutex to prevent shooting
+         * ourselves in the foot.
+         * When the hub is disconnected but we are in the middle of some
+         * operation, we cannot destroy this structure right away because
+         * the pending operation might use it.
+         */
+        size_t pending_ops_count;
+        /** Guard for pending_ops_count. */
+        fibril_mutex_t pending_ops_mutex;
+        /** Condition variable for pending_ops_count. */
+        fibril_condvar_t pending_ops_cv;
+
 };