include/qemu/yank.h

   1 /*
   2  * QEMU yank feature
   3  *
   4  * Copyright (c) Lukas Straub <lukasstraub2@web.de>
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7  * See the COPYING file in the top-level directory.
   8  */
   9
  10 #ifndef YANK_H
  11 #define YANK_H
  12
  13 #include "qapi/qapi-types-yank.h"
  14
  15 typedef void (YankFn)(void *opaque);
  16
  17 /**
  18  * yank_register_instance: Register a new instance.
  19  *
  20  * This registers a new instance for yanking. Must be called before any yank
  21  * function is registered for this instance.
  22  *
  23  * This function is thread-safe.
  24  *
  25  * @instance: The instance.
  26  * @errp: Error object.
  27  *
  28  * Returns true on success or false if an error occured.
  29  */
  30 bool yank_register_instance(const YankInstance *instance, Error **errp);
  31
  32 /**
  33  * yank_unregister_instance: Unregister a instance.
  34  *
  35  * This unregisters a instance. Must be called only after every yank function
  36  * of the instance has been unregistered.
  37  *
  38  * This function is thread-safe.
  39  *
  40  * @instance: The instance.
  41  */
  42 void yank_unregister_instance(const YankInstance *instance);
  43
  44 /**
  45  * yank_register_function: Register a yank function
  46  *
  47  * This registers a yank function. All limitations of qmp oob commands apply
  48  * to the yank function as well. See docs/devel/qapi-code-gen.txt under
  49  * "An OOB-capable command handler must satisfy the following conditions".
  50  *
  51  * This function is thread-safe.
  52  *
  53  * @instance: The instance.
  54  * @func: The yank function.
  55  * @opaque: Will be passed to the yank function.
  56  */
  57 void yank_register_function(const YankInstance *instance,
  58                             YankFn *func,
  59                             void *opaque);
  60
  61 /**
  62  * yank_unregister_function: Unregister a yank function
  63  *
  64  * This unregisters a yank function.
  65  *
  66  * This function is thread-safe.
  67  *
  68  * @instance: The instance.
  69  * @func: func that was passed to yank_register_function.
  70  * @opaque: opaque that was passed to yank_register_function.
  71  */
  72 void yank_unregister_function(const YankInstance *instance,
  73                               YankFn *func,
  74                               void *opaque);
  75
  76 /**
  77  * yank_generic_iochannel: Generic yank function for iochannel
  78  *
  79  * This is a generic yank function which will call qio_channel_shutdown on the
  80  * provided QIOChannel.
  81  *
  82  * @opaque: QIOChannel to shutdown
  83  */
  84 void yank_generic_iochannel(void *opaque);
  85
  86 #define BLOCKDEV_YANK_INSTANCE(the_node_name) (&(YankInstance) { \
  87         .type = YANK_INSTANCE_TYPE_BLOCK_NODE, \
  88         .u.block_node.node_name = (the_node_name) })
  89
  90 #define CHARDEV_YANK_INSTANCE(the_id) (&(YankInstance) { \
  91         .type = YANK_INSTANCE_TYPE_CHARDEV, \
  92         .u.chardev.id = (the_id) })
  93
  94 #define MIGRATION_YANK_INSTANCE (&(YankInstance) { \
  95         .type = YANK_INSTANCE_TYPE_MIGRATION })
  96
  97 #endif