include/block/snapshot.h

   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