Changes between Version 12 and Version 13 of DeviceDrivers

Timestamp:

2011-11-12T22:12:35Z (12 years ago)

Author:

Jiri Svoboda

Comment:

When to allocate soft state

DeviceDrivers

@@ -84 +84 @@
 The function ''ddf_dev_data_alloc'' allocates a driver-specific data strutcure ''size'' bytes large, associated with the device ''dev''. The structure will not be deallocated by the framework until the ''dev_remove'' or ''dev_gone'' entry point returns '''and''' control exits all driver entry points that are invoked with ''dev'' as a parameter. (Internally, this is achieved using reference counting).
 
-The function ''ddf_fun_data_alloc'' allocates a driver-specific data structure ''size'' bytes large, associated with the function ''fun''. The structure will not be deallocated by the framework until ''ddf_fun_destroy()'' is called '''and''' control exits all driver entry points that are invoked with ''fun'' as parameter.
+The function ''ddf_fun_data_alloc'' allocates a driver-specific data structure ''size'' bytes large, associated with the function ''fun''. The structure will not be deallocated by the framework until ''ddf_fun_destroy()'' is called '''and''' control exits all driver entry points that are invoked with ''fun'' as parameter. 'ddf_dev_data_alloc'' is normally called from within the ''add_device'' emtry point.
 
-In practice, as long as you don't copy the pointer to device or function soft-state to a global/heap structure or pass it to another thread, it can never become dangling. As long as you have the reference, it is valid (i.e. points to an allocated block).
+In practice, as long as you don't copy the pointer to device or function soft-state to a global/heap structure or pass it to another thread, it can never become dangling. As long as you have the reference, it is valid (i.e. points to an allocated block). ''ddf_fun_data_alloc'' is called on an unbound function (after creating, before binding).
 
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