1
0
mirror of git://sourceware.org/git/lvm2.git synced 2024-12-22 17:35:59 +03:00
lvm2/lib/format_text/import-export.h
Alasdair G Kergon 6407d184d1 cache: Store metadata size and checksum.
Refactor the recent metadata-reading optimisation patches.

Remove the recently-added cache fields from struct labeller
and struct format_instance.

Instead, introduce struct lvmcache_vgsummary to wrap the VG information
that lvmcache holds and add the metadata size and checksum to it.

Allow this VG summary information to be looked up by metadata size +
checksum.  Adjust the debug log messages to make it clear when this
shortcut has been successful.

(This changes the optimisation slightly, and might be extendable
further.)

Add struct cached_vg_fmtdata to format-specific vg_read calls to
preserve state alongside the VG across separate calls and indicate
if the details supplied match, avoiding the need to read and
process the VG metadata again.
2015-03-18 23:43:02 +00:00

92 lines
2.9 KiB
C

/*
* Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This file is part of LVM2.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _LVM_TEXT_IMPORT_EXPORT_H
#define _LVM_TEXT_IMPORT_EXPORT_H
#include "config.h"
#include "metadata.h"
#include "lvmcache.h"
#include <stdio.h>
/*
* Constants to identify files this code can parse.
*/
#define CONTENTS_FIELD "contents"
#define CONTENTS_VALUE "Text Format Volume Group"
#define FORMAT_VERSION_FIELD "version"
#define FORMAT_VERSION_VALUE 1
/*
* VGs, PVs and LVs all have status bitsets, we gather together
* common code for reading and writing them.
*/
enum {
COMPATIBLE_FLAG = 0x0,
VG_FLAGS,
PV_FLAGS,
LV_FLAGS,
STATUS_FLAG = 0x8,
};
struct text_vg_version_ops {
int (*check_version) (const struct dm_config_tree * cf);
struct volume_group *(*read_vg) (struct format_instance * fid,
const struct dm_config_tree *cf,
unsigned use_cached_pvs);
void (*read_desc) (struct dm_pool * mem, const struct dm_config_tree *cf,
time_t *when, char **desc);
int (*read_vgname) (const struct format_type *fmt,
const struct dm_config_tree *cft,
struct lvmcache_vgsummary *vgsummary);
};
struct text_vg_version_ops *text_vg_vsn1_init(void);
int print_flags(uint64_t status, int type, char *buffer, size_t size);
int read_flags(uint64_t *status, int type, const struct dm_config_value *cv);
char *alloc_printed_tags(struct dm_list *tags);
int read_tags(struct dm_pool *mem, struct dm_list *tags, const struct dm_config_value *cv);
int text_vg_export_file(struct volume_group *vg, const char *desc, FILE *fp);
size_t text_vg_export_raw(struct volume_group *vg, const char *desc, char **buf);
struct volume_group *text_vg_import_file(struct format_instance *fid,
const char *file,
time_t *when, char **desc);
struct volume_group *text_vg_import_fd(struct format_instance *fid,
const char *file,
struct cached_vg_fmtdata **vg_fmtdata,
unsigned *use_previous_vg,
int single_device,
struct device *dev,
off_t offset, uint32_t size,
off_t offset2, uint32_t size2,
checksum_fn_t checksum_fn,
uint32_t checksum,
time_t *when, char **desc);
int text_vgname_import(const struct format_type *fmt,
struct device *dev,
off_t offset, uint32_t size,
off_t offset2, uint32_t size2,
checksum_fn_t checksum_fn,
int checksum_only,
struct lvmcache_vgsummary *vgsummary);
#endif