xref: /qemu/plugins/plugin.h (revision 19f9c044)
1 /*
2  * Plugin Shared Internal Functions
3  *
4  * Copyright (C) 2019, Linaro
5  *
6  * License: GNU GPL, version 2 or later.
7  *   See the COPYING file in the top-level directory.
8  *
9  * SPDX-License-Identifier: GPL-2.0-or-later
10  */
11 
12 #ifndef PLUGIN_H
13 #define PLUGIN_H
14 
15 #include <gmodule.h>
16 #include "qemu/qht.h"
17 
18 #define QEMU_PLUGIN_MIN_VERSION 2
19 
20 /* global state */
21 struct qemu_plugin_state {
22     QTAILQ_HEAD(, qemu_plugin_ctx) ctxs;
23     QLIST_HEAD(, qemu_plugin_cb) cb_lists[QEMU_PLUGIN_EV_MAX];
24     /*
25      * Use the HT as a hash map by inserting k == v, which saves memory as
26      * documented by GLib. The parent struct is obtained with container_of().
27      */
28     GHashTable *id_ht;
29     /*
30      * Use the HT as a hash map. Note that we could use a list here,
31      * but with the HT we avoid adding a field to CPUState.
32      */
33     GHashTable *cpu_ht;
34     DECLARE_BITMAP(mask, QEMU_PLUGIN_EV_MAX);
35     /*
36      * @lock protects the struct as well as ctx->uninstalling.
37      * The lock must be acquired by all API ops.
38      * The lock is recursive, which greatly simplifies things, e.g.
39      * callback registration from qemu_plugin_vcpu_for_each().
40      */
41     QemuRecMutex lock;
42     /*
43      * HT of callbacks invoked from helpers. All entries are freed when
44      * the code cache is flushed.
45      */
46     struct qht dyn_cb_arr_ht;
47     /* How many vcpus were started */
48     int num_vcpus;
49 };
50 
51 
52 struct qemu_plugin_ctx {
53     GModule *handle;
54     qemu_plugin_id_t id;
55     struct qemu_plugin_cb *callbacks[QEMU_PLUGIN_EV_MAX];
56     QTAILQ_ENTRY(qemu_plugin_ctx) entry;
57     /*
58      * keep a reference to @desc until uninstall, so that plugins do not have
59      * to strdup plugin args.
60      */
61     struct qemu_plugin_desc *desc;
62     bool installing;
63     bool uninstalling;
64     bool resetting;
65 };
66 
67 struct qemu_plugin_ctx *plugin_id_to_ctx_locked(qemu_plugin_id_t id);
68 
69 void plugin_register_inline_op(GArray **arr,
70                                enum qemu_plugin_mem_rw rw,
71                                enum qemu_plugin_op op, void *ptr,
72                                uint64_t imm);
73 
74 void plugin_reset_uninstall(qemu_plugin_id_t id,
75                             qemu_plugin_simple_cb_t cb,
76                             bool reset);
77 
78 void plugin_register_cb(qemu_plugin_id_t id, enum qemu_plugin_event ev,
79                         void *func);
80 
81 void plugin_unregister_cb__locked(struct qemu_plugin_ctx *ctx,
82                                   enum qemu_plugin_event ev);
83 
84 void
85 plugin_register_cb_udata(qemu_plugin_id_t id, enum qemu_plugin_event ev,
86                          void *func, void *udata);
87 
88 void
89 plugin_register_dyn_cb__udata(GArray **arr,
90                               qemu_plugin_vcpu_udata_cb_t cb,
91                               enum qemu_plugin_cb_flags flags, void *udata);
92 
93 
94 void plugin_register_vcpu_mem_cb(GArray **arr,
95                                  void *cb,
96                                  enum qemu_plugin_cb_flags flags,
97                                  enum qemu_plugin_mem_rw rw,
98                                  void *udata);
99 
100 void exec_inline_op(struct qemu_plugin_dyn_cb *cb);
101 
102 int plugin_num_vcpus(void);
103 
104 #endif /* PLUGIN_H */
105