a783f8ad4e
...that maintains compatibility with existing Xen toolstacks.
Xen toolstacks instantiate PV backends by simply writing information into
xenstore and expecting a backend implementation to be watching for this.
This patch adds a new 'xen-backend' module to allow individual XenDevice
implementations to register create and destroy functions. The creator
will be called when a tool-stack instantiates a new backend in this way,
and the destructor will then be called after the resulting XenDevice
object is unrealized.
To support this it is also necessary to add new watchers into the XenBus
implementation to handle enumeration of new backends and also destruction
of XenDevice-s when the toolstack sets the backend 'online' key to 0.
NOTE: This patch only adds the framework. A subsequent patch will add a
creator function for xen-block devices.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
69 lines
2.4 KiB
C
69 lines
2.4 KiB
C
/*
|
|
* QEMU Module Infrastructure
|
|
*
|
|
* Copyright IBM, Corp. 2009
|
|
*
|
|
* Authors:
|
|
* Anthony Liguori <aliguori@us.ibm.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2. See
|
|
* the COPYING file in the top-level directory.
|
|
*
|
|
*/
|
|
|
|
#ifndef QEMU_MODULE_H
|
|
#define QEMU_MODULE_H
|
|
|
|
|
|
#define DSO_STAMP_FUN glue(qemu_stamp, CONFIG_STAMP)
|
|
#define DSO_STAMP_FUN_STR stringify(DSO_STAMP_FUN)
|
|
|
|
#ifdef BUILD_DSO
|
|
void DSO_STAMP_FUN(void);
|
|
/* This is a dummy symbol to identify a loaded DSO as a QEMU module, so we can
|
|
* distinguish "version mismatch" from "not a QEMU module", when the stamp
|
|
* check fails during module loading */
|
|
void qemu_module_dummy(void);
|
|
|
|
#define module_init(function, type) \
|
|
static void __attribute__((constructor)) do_qemu_init_ ## function(void) \
|
|
{ \
|
|
register_dso_module_init(function, type); \
|
|
}
|
|
#else
|
|
/* This should not be used directly. Use block_init etc. instead. */
|
|
#define module_init(function, type) \
|
|
static void __attribute__((constructor)) do_qemu_init_ ## function(void) \
|
|
{ \
|
|
register_module_init(function, type); \
|
|
}
|
|
#endif
|
|
|
|
typedef enum {
|
|
MODULE_INIT_BLOCK,
|
|
MODULE_INIT_OPTS,
|
|
MODULE_INIT_QOM,
|
|
MODULE_INIT_TRACE,
|
|
MODULE_INIT_XEN_BACKEND,
|
|
MODULE_INIT_MAX
|
|
} module_init_type;
|
|
|
|
#define block_init(function) module_init(function, MODULE_INIT_BLOCK)
|
|
#define opts_init(function) module_init(function, MODULE_INIT_OPTS)
|
|
#define type_init(function) module_init(function, MODULE_INIT_QOM)
|
|
#define trace_init(function) module_init(function, MODULE_INIT_TRACE)
|
|
#define xen_backend_init(function) module_init(function, \
|
|
MODULE_INIT_XEN_BACKEND)
|
|
|
|
#define block_module_load_one(lib) module_load_one("block-", lib)
|
|
#define ui_module_load_one(lib) module_load_one("ui-", lib)
|
|
#define audio_module_load_one(lib) module_load_one("audio-", lib)
|
|
|
|
void register_module_init(void (*fn)(void), module_init_type type);
|
|
void register_dso_module_init(void (*fn)(void), module_init_type type);
|
|
|
|
void module_call_init(module_init_type type);
|
|
void module_load_one(const char *prefix, const char *lib_name);
|
|
|
|
#endif
|