qemu-e2k/block_int.h
edison 51ef67270b Copy snapshots out of QCOW2 disk
In order to backup snapshots, created from QCOW2 iamge, we want to copy snapshots out of QCOW2 disk to a seperate storage.
The following patch adds a new option in "qemu-img": qemu-img convert -f qcow2 -O qcow2 -s snapshot_name src_img bck_img.
Right now, it only supports to copy the full snapshot, delta snapshot is on the way.

Changes from V1: all the comments from Kevin are addressed:
Add read-only checking
Fix coding style
Change the name from bdrv_snapshot_load to bdrv_snapshot_load_tmp

Signed-off-by: Disheng Su <edison@cloud.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-10-22 14:49:35 +02:00

255 lines
9.4 KiB
C

/*
* QEMU System Emulator block driver
*
* Copyright (c) 2003 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef BLOCK_INT_H
#define BLOCK_INT_H
#include "block.h"
#include "qemu-option.h"
#include "qemu-queue.h"
#define BLOCK_FLAG_ENCRYPT 1
#define BLOCK_FLAG_COMPRESS 2
#define BLOCK_FLAG_COMPAT6 4
#define BLOCK_OPT_SIZE "size"
#define BLOCK_OPT_ENCRYPT "encryption"
#define BLOCK_OPT_COMPAT6 "compat6"
#define BLOCK_OPT_BACKING_FILE "backing_file"
#define BLOCK_OPT_BACKING_FMT "backing_fmt"
#define BLOCK_OPT_CLUSTER_SIZE "cluster_size"
#define BLOCK_OPT_PREALLOC "preallocation"
typedef struct AIOPool {
void (*cancel)(BlockDriverAIOCB *acb);
int aiocb_size;
BlockDriverAIOCB *free_aiocb;
} AIOPool;
struct BlockDriver {
const char *format_name;
int instance_size;
int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
int (*bdrv_probe_device)(const char *filename);
int (*bdrv_open)(BlockDriverState *bs, int flags);
int (*bdrv_file_open)(BlockDriverState *bs, const char *filename, int flags);
int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors);
int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors);
void (*bdrv_close)(BlockDriverState *bs);
int (*bdrv_create)(const char *filename, QEMUOptionParameter *options);
void (*bdrv_flush)(BlockDriverState *bs);
int (*bdrv_is_allocated)(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, int *pnum);
int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
int (*bdrv_make_empty)(BlockDriverState *bs);
/* aio */
BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
BlockDriverCompletionFunc *cb, void *opaque);
int (*bdrv_aio_multiwrite)(BlockDriverState *bs, BlockRequest *reqs,
int num_reqs);
int (*bdrv_merge_requests)(BlockDriverState *bs, BlockRequest* a,
BlockRequest *b);
const char *protocol_name;
int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
int64_t (*bdrv_getlength)(BlockDriverState *bs);
int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors);
int (*bdrv_snapshot_create)(BlockDriverState *bs,
QEMUSnapshotInfo *sn_info);
int (*bdrv_snapshot_goto)(BlockDriverState *bs,
const char *snapshot_id);
int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id);
int (*bdrv_snapshot_list)(BlockDriverState *bs,
QEMUSnapshotInfo **psn_info);
int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
const char *snapshot_name);
int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf,
int64_t pos, int size);
int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
int64_t pos, int size);
int (*bdrv_change_backing_file)(BlockDriverState *bs,
const char *backing_file, const char *backing_fmt);
/* removable device specific */
int (*bdrv_is_inserted)(BlockDriverState *bs);
int (*bdrv_media_changed)(BlockDriverState *bs);
int (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
int (*bdrv_set_locked)(BlockDriverState *bs, int locked);
/* to control generic scsi devices */
int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);
BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
unsigned long int req, void *buf,
BlockDriverCompletionFunc *cb, void *opaque);
/* List of options for creating images, terminated by name == NULL */
QEMUOptionParameter *create_options;
/*
* Returns 0 for completed check, -errno for internal errors.
* The check results are stored in result.
*/
int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result);
void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
/*
* Returns 1 if newly created images are guaranteed to contain only
* zeros, 0 otherwise.
*/
int (*bdrv_has_zero_init)(BlockDriverState *bs);
QLIST_ENTRY(BlockDriver) list;
};
struct BlockDriverState {
int64_t total_sectors; /* if we are reading a disk image, give its
size in sectors */
int read_only; /* if true, the media is read only */
int keep_read_only; /* if true, the media was requested to stay read only */
int open_flags; /* flags used to open the file, re-used for re-open */
int removable; /* if true, the media can be removed */
int locked; /* if true, the media cannot temporarily be ejected */
int tray_open; /* if true, the virtual tray is open */
int encrypted; /* if true, the media is encrypted */
int valid_key; /* if true, a valid encryption key has been set */
int sg; /* if true, the device is a /dev/sg* */
/* event callback when inserting/removing */
void (*change_cb)(void *opaque);
void *change_opaque;
BlockDriver *drv; /* NULL means no media */
void *opaque;
DeviceState *peer;
char filename[1024];
char backing_file[1024]; /* if non zero, the image is a diff of
this file image */
char backing_format[16]; /* if non-zero and backing_file exists */
int is_temporary;
int media_changed;
BlockDriverState *backing_hd;
BlockDriverState *file;
/* async read/write emulation */
void *sync_aiocb;
/* I/O stats (display with "info blockstats"). */
uint64_t rd_bytes;
uint64_t wr_bytes;
uint64_t rd_ops;
uint64_t wr_ops;
uint64_t wr_highest_sector;
/* Whether the disk can expand beyond total_sectors */
int growable;
/* the memory alignment required for the buffers handled by this driver */
int buffer_alignment;
/* do we need to tell the quest if we have a volatile write cache? */
int enable_write_cache;
/* NOTE: the following infos are only hints for real hardware
drivers. They are not used by the block driver */
int cyls, heads, secs, translation;
int type;
BlockErrorAction on_read_error, on_write_error;
char device_name[32];
unsigned long *dirty_bitmap;
int64_t dirty_count;
QTAILQ_ENTRY(BlockDriverState) list;
void *private;
};
struct BlockDriverAIOCB {
AIOPool *pool;
BlockDriverState *bs;
BlockDriverCompletionFunc *cb;
void *opaque;
BlockDriverAIOCB *next;
};
void get_tmp_filename(char *filename, int size);
void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
BlockDriverCompletionFunc *cb, void *opaque);
void qemu_aio_release(void *p);
void *qemu_blockalign(BlockDriverState *bs, size_t size);
#ifdef _WIN32
int is_windows_drive(const char *filename);
#endif
typedef struct BlockConf {
BlockDriverState *bs;
uint16_t physical_block_size;
uint16_t logical_block_size;
uint16_t min_io_size;
uint32_t opt_io_size;
} BlockConf;
static inline unsigned int get_physical_block_exp(BlockConf *conf)
{
unsigned int exp = 0, size;
for (size = conf->physical_block_size;
size > conf->logical_block_size;
size >>= 1) {
exp++;
}
return exp;
}
#define DEFINE_BLOCK_PROPERTIES(_state, _conf) \
DEFINE_PROP_DRIVE("drive", _state, _conf.bs), \
DEFINE_PROP_UINT16("logical_block_size", _state, \
_conf.logical_block_size, 512), \
DEFINE_PROP_UINT16("physical_block_size", _state, \
_conf.physical_block_size, 512), \
DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 0), \
DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 0)
#endif /* BLOCK_INT_H */