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 void module_allow_arch(const char *arch);
  76
  77 /**
  78  * DOC: module info annotation macros
  79  *
  80  * `scripts/modinfo-collect.py` will collect module info,
  81  * using the preprocessor and -DQEMU_MODINFO.
  82  *
  83  * `scripts/modinfo-generate.py` will create a module meta-data database
  84  * from the collected information so qemu knows about module
  85  * dependencies and QOM objects implemented by modules.
  86  *
  87  * See `*.modinfo` and `modinfo.c` in the build directory to check the
  88  * script results.
  89  */
  90 #ifdef QEMU_MODINFO
  91 # define modinfo(kind, value) \
  92     MODINFO_START kind value MODINFO_END
  93 #else
  94 # define modinfo(kind, value)
  95 #endif
  96
  97 /**
  98  * module_obj
  99  *
 100  * @name: QOM type.
 101  *
 102  * This module implements QOM type @name.
 103  */
 104 #define module_obj(name) modinfo(obj, name)
 105
 106 /**
 107  * module_dep
 108  *
 109  * @name: module name
 110  *
 111  * This module depends on module @name.
 112  */
 113 #define module_dep(name) modinfo(dep, name)
 114
 115 /**
 116  * module_arch
 117  *
 118  * @name: target architecture
 119  *
 120  * This module is for target architecture @arch.
 121  *
 122  * Note that target-dependent modules are tagged automatically, so
 123  * this is only needed in case target-independent modules should be
 124  * restricted.  Use case example: the ccw bus is implemented by s390x
 125  * only.
 126  */
 127 #define module_arch(name) modinfo(arch, name)
 128
 129 /**
 130  * module_opts
 131  *
 132  * @name: QemuOpts name
 133  *
 134  * This module registers QemuOpts @name.
 135  */
 136 #define module_opts(name) modinfo(opts, name)
 137
 138 /*
 139  * module info database
 140  *
 141  * scripts/modinfo-generate.c will build this using the data collected
 142  * by scripts/modinfo-collect.py
 143  */
 144 typedef struct QemuModinfo QemuModinfo;
 145 struct QemuModinfo {
 146     const char *name;
 147     const char *arch;
 148     const char **objs;
 149     const char **deps;
 150     const char **opts;
 151 };
 152 extern const QemuModinfo qemu_modinfo[];
 153 void module_init_info(const QemuModinfo *info);
 154
 155 #endif