xref: /openbmc/qemu/include/block/snapshot.h (revision 3161f9f4)
1 /*
2  * Block layer snapshot related functions
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #ifndef SNAPSHOT_H
26 #define SNAPSHOT_H
27 
28 #include "block/graph-lock.h"
29 #include "qapi/qapi-builtin-types.h"
30 
31 #define SNAPSHOT_OPT_BASE       "snapshot."
32 #define SNAPSHOT_OPT_ID         "snapshot.id"
33 #define SNAPSHOT_OPT_NAME       "snapshot.name"
34 
35 extern QemuOptsList internal_snapshot_opts;
36 
37 typedef struct QEMUSnapshotInfo {
38     char id_str[128]; /* unique snapshot id */
39     /* the following fields are informative. They are not needed for
40        the consistency of the snapshot */
41     char name[256]; /* user chosen name */
42     uint64_t vm_state_size; /* VM state info size */
43     uint32_t date_sec; /* UTC date of the snapshot */
44     uint32_t date_nsec;
45     uint64_t vm_clock_nsec; /* VM clock relative to boot */
46     uint64_t icount; /* record/replay step */
47 } QEMUSnapshotInfo;
48 
49 /*
50  * Global state (GS) API. These functions run under the BQL.
51  *
52  * See include/block/block-global-state.h for more information about
53  * the GS API.
54  */
55 
56 int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
57                        const char *name);
58 bool bdrv_snapshot_find_by_id_and_name(BlockDriverState *bs,
59                                        const char *id,
60                                        const char *name,
61                                        QEMUSnapshotInfo *sn_info,
62                                        Error **errp);
63 
64 int GRAPH_RDLOCK bdrv_can_snapshot(BlockDriverState *bs);
65 
66 int GRAPH_RDLOCK
67 bdrv_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
68 
69 int GRAPH_UNLOCKED
70 bdrv_snapshot_goto(BlockDriverState *bs, const char *snapshot_id, Error **errp);
71 
72 int GRAPH_RDLOCK
73 bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id,
74                      const char *name, Error **errp);
75 
76 int bdrv_snapshot_list(BlockDriverState *bs,
77                        QEMUSnapshotInfo **psn_info);
78 int bdrv_snapshot_load_tmp(BlockDriverState *bs,
79                            const char *snapshot_id,
80                            const char *name,
81                            Error **errp);
82 int bdrv_snapshot_load_tmp_by_id_or_name(BlockDriverState *bs,
83                                          const char *id_or_name,
84                                          Error **errp);
85 
86 
87 /*
88  * Group operations. All block drivers are involved.
89  * These functions will properly handle dataplane (take aio_context_acquire
90  * when appropriate for appropriate block drivers
91  */
92 
93 bool bdrv_all_can_snapshot(bool has_devices, strList *devices,
94                            Error **errp);
95 int bdrv_all_delete_snapshot(const char *name,
96                              bool has_devices, strList *devices,
97                              Error **errp);
98 int bdrv_all_goto_snapshot(const char *name,
99                            bool has_devices, strList *devices,
100                            Error **errp);
101 int bdrv_all_has_snapshot(const char *name,
102                           bool has_devices, strList *devices,
103                           Error **errp);
104 int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
105                              BlockDriverState *vm_state_bs,
106                              uint64_t vm_state_size,
107                              bool has_devices,
108                              strList *devices,
109                              Error **errp);
110 
111 BlockDriverState *bdrv_all_find_vmstate_bs(const char *vmstate_bs,
112                                            bool has_devices, strList *devices,
113                                            Error **errp);
114 
115 #endif
116