include/qemu/module.h

   1 /*
   2  * QEMU Module Infrastructure
   3  *
   4  * Copyright IBM, Corp. 2009
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 #ifndef QEMU_MODULE_H
  15 #define QEMU_MODULE_H
  16
  17
  18 #define DSO_STAMP_FUN         glue(qemu_stamp, CONFIG_STAMP)
  19 #define DSO_STAMP_FUN_STR     stringify(DSO_STAMP_FUN)
  20
  21 #ifdef BUILD_DSO
  22 void DSO_STAMP_FUN(void);
  23 /* This is a dummy symbol to identify a loaded DSO as a QEMU module, so we can
  24  * distinguish "version mismatch" from "not a QEMU module", when the stamp
  25  * check fails during module loading */
  26 void qemu_module_dummy(void);
  27
  28 #define module_init(function, type)                                         \
  29 static void __attribute__((constructor)) do_qemu_init_ ## function(void)    \
  30 {                                                                           \
  31     register_dso_module_init(function, type);                               \
  32 }
  33 #else
  34 /* This should not be used directly.  Use block_init etc. instead.  */
  35 #define module_init(function, type)                                         \
  36 static void __attribute__((constructor)) do_qemu_init_ ## function(void)    \
  37 {                                                                           \
  38     register_module_init(function, type);                                   \
  39 }
  40 #endif
  41
  42 typedef enum {
  43     MODULE_INIT_MIGRATION,
  44     MODULE_INIT_BLOCK,
  45     MODULE_INIT_OPTS,
  46     MODULE_INIT_QOM,
  47     MODULE_INIT_TRACE,
  48     MODULE_INIT_XEN_BACKEND,
  49     MODULE_INIT_LIBQOS,
  50     MODULE_INIT_FUZZ_TARGET,
  51     MODULE_INIT_MAX
  52 } module_init_type;
  53
  54 #define block_init(function) module_init(function, MODULE_INIT_BLOCK)
  55 #define opts_init(function) module_init(function, MODULE_INIT_OPTS)
  56 #define type_init(function) module_init(function, MODULE_INIT_QOM)
  57 #define trace_init(function) module_init(function, MODULE_INIT_TRACE)
  58 #define xen_backend_init(function) module_init(function, \
  59                                                MODULE_INIT_XEN_BACKEND)
  60 #define libqos_init(function) module_init(function, MODULE_INIT_LIBQOS)
  61 #define fuzz_target_init(function) module_init(function, \
  62                                                MODULE_INIT_FUZZ_TARGET)
  63 #define migration_init(function) module_init(function, MODULE_INIT_MIGRATION)
  64 #define block_module_load_one(lib) module_load_one("block-", lib, false)
  65 #define ui_module_load_one(lib) module_load_one("ui-", lib, false)
  66 #define audio_module_load_one(lib) module_load_one("audio-", lib, false)
  67
  68 void register_module_init(void (*fn)(void), module_init_type type);
  69 void register_dso_module_init(void (*fn)(void), module_init_type type);
  70
  71 void module_call_init(module_init_type type);
  72 bool module_load_one(const char *prefix, const char *lib_name, bool mayfail);
  73 void module_load_qom_one(const char *type);
  74 void module_load_qom_all(void);
  75
  76 /**
  77  * DOC: module info annotation macros
  78  *
  79  * `scripts/modinfo-collect.py` will collect module info,
  80  * using the preprocessor and -DQEMU_MODINFO.
  81  *
  82  * `scripts/modinfo-generate.py` will create a module meta-data database
  83  * from the collected information so qemu knows about module
  84  * dependencies and QOM objects implemented by modules.
  85  *
  86  * See `*.modinfo` and `modinfo.c` in the build directory to check the
  87  * script results.
  88  */
  89 #ifdef QEMU_MODINFO
  90 # define modinfo(kind, value) \
  91     MODINFO_START kind value MODINFO_END
  92 #else
  93 # define modinfo(kind, value)
  94 #endif
  95
  96 /**
  97  * module_obj
  98  *
  99  * @name: QOM type.
 100  *
 101  * This module implements QOM type @name.
 102  */
 103 #define module_obj(name) modinfo(obj, name)
 104
 105 /**
 106  * module_dep
 107  *
 108  * @name: module name
 109  *
 110  * This module depends on module @name.
 111  */
 112 #define module_dep(name) modinfo(dep, name)
 113
 114 /**
 115  * module_arch
 116  *
 117  * @name: target architecture
 118  *
 119  * This module is for target architecture @arch.
 120  *
 121  * Note that target-dependent modules are tagged automatically, so
 122  * this is only needed in case target-independent modules should be
 123  * restricted.  Use case example: the ccw bus is implemented by s390x
 124  * only.
 125  */
 126 #define module_arch(name) modinfo(arch, name)
 127
 128 /**
 129  * module_opts
 130  *
 131  * @name: QemuOpts name
 132  *
 133  * This module registers QemuOpts @name.
 134  */
 135 #define module_opts(name) modinfo(opts, name)
 136
 137 /*
 138  * module info database
 139  *
 140  * scripts/modinfo-generate.c will build this using the data collected
 141  * by scripts/modinfo-collect.py
 142  */
 143 typedef struct QemuModinfo QemuModinfo;
 144 struct QemuModinfo {
 145     const char *name;
 146     const char *arch;
 147     const char **objs;
 148     const char **deps;
 149     const char **opts;
 150 };
 151 extern const QemuModinfo qemu_modinfo[];
 152 void module_init_info(const QemuModinfo *info);
 153
 154 #endif