1
0
mirror of git://sourceware.org/git/lvm2.git synced 2024-10-28 11:55:55 +03:00
lvm2/lib/metadata/metadata.h
2006-05-02 07:14:43 +00:00

615 lines
18 KiB
C

/*
* Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004 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 General Public License v.2.
*
* You should have received a copy of the GNU 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
*/
/*
* This is the in core representation of a volume group and its
* associated physical and logical volumes.
*/
#ifndef _LVM_METADATA_H
#define _LVM_METADATA_H
#include "ctype.h"
#include "dev-cache.h"
#include "lvm-string.h"
#include "uuid.h"
#define MAX_STRIPES 128
#define SECTOR_SHIFT 9L
#define SECTOR_SIZE ( 1L << SECTOR_SHIFT )
#define STRIPE_SIZE_MIN ( getpagesize() >> SECTOR_SHIFT) /* PAGESIZE in sectors */
#define STRIPE_SIZE_MAX ( 512L * 1024L >> SECTOR_SHIFT) /* 512 KB in sectors */
#define STRIPE_SIZE_LIMIT ((UINT_MAX >> 2) + 1)
#define PV_MIN_SIZE ( 512L * 1024L >> SECTOR_SHIFT) /* 512 KB in sectors */
#define PE_ALIGN (65536UL >> SECTOR_SHIFT) /* PE alignment */
#define MAX_RESTRICTED_LVS 255 /* Used by FMT_RESTRICTED_LVIDS */
/* Various flags */
/* Note that the bits no longer necessarily correspond to LVM1 disk format */
#define PARTIAL_VG 0x00000001 /* VG */
#define EXPORTED_VG 0x00000002 /* VG PV */
#define RESIZEABLE_VG 0x00000004 /* VG */
/* May any free extents on this PV be used or must they be left free? */
#define ALLOCATABLE_PV 0x00000008 /* PV */
#define SPINDOWN_LV 0x00000010 /* LV */
#define BADBLOCK_ON 0x00000020 /* LV */
#define VISIBLE_LV 0x00000040 /* LV */
#define FIXED_MINOR 0x00000080 /* LV */
/* FIXME Remove when metadata restructuring is completed */
#define SNAPSHOT 0x00001000 /* LV - internal use only */
#define PVMOVE 0x00002000 /* VG LV SEG */
#define LOCKED 0x00004000 /* LV */
#define MIRRORED 0x00008000 /* LV - internal use only */
#define VIRTUAL 0x00010000 /* LV - internal use only */
#define MIRROR_LOG 0x00020000 /* LV */
#define MIRROR_IMAGE 0x00040000 /* LV */
#define ACTIVATE_EXCL 0x00080000 /* LV - internal use only */
#define PRECOMMITTED 0x00100000 /* VG - internal use only */
#define LVM_READ 0x00000100 /* LV VG */
#define LVM_WRITE 0x00000200 /* LV VG */
#define CLUSTERED 0x00000400 /* VG */
#define SHARED 0x00000800 /* VG */
/* Format features flags */
#define FMT_SEGMENTS 0x00000001 /* Arbitrary segment params? */
#define FMT_MDAS 0x00000002 /* Proper metadata areas? */
#define FMT_TAGS 0x00000004 /* Tagging? */
#define FMT_UNLIMITED_VOLS 0x00000008 /* Unlimited PVs/LVs? */
#define FMT_RESTRICTED_LVIDS 0x00000010 /* LVID <= 255 */
#define FMT_ORPHAN_ALLOCATABLE 0x00000020 /* Orphan PV allocatable? */
#define FMT_PRECOMMIT 0x00000040 /* Supports pre-commit? */
#define FMT_RESIZE_PV 0x00000080 /* Supports pvresize? */
#define FMT_UNLIMITED_STRIPESIZE 0x00000100 /* Unlimited stripe size? */
typedef enum {
ALLOC_INVALID,
ALLOC_INHERIT,
ALLOC_CONTIGUOUS,
ALLOC_NORMAL,
ALLOC_ANYWHERE
} alloc_policy_t;
typedef enum {
AREA_UNASSIGNED = 0,
AREA_PV,
AREA_LV
} area_type_t;
struct cmd_context;
struct format_handler;
struct labeller;
struct format_type {
struct list list;
struct cmd_context *cmd;
struct format_handler *ops;
struct labeller *labeller;
const char *name;
const char *alias;
uint32_t features;
void *library;
void *private;
};
struct pv_segment {
struct list list; /* Member of pv->segments: ordered list
* covering entire data area on this PV */
struct physical_volume *pv;
uint32_t pe;
uint32_t len;
struct lv_segment *lvseg; /* NULL if free space */
uint32_t lv_area; /* Index to area in LV segment */
};
struct physical_volume {
struct id id;
struct device *dev;
const struct format_type *fmt;
const char *vg_name;
struct id vgid;
uint32_t status;
uint64_t size;
/* physical extents */
uint32_t pe_size;
uint64_t pe_start;
uint32_t pe_count;
uint32_t pe_alloc_count;
struct list segments; /* Ordered pv_segments covering complete PV */
struct list tags;
};
struct metadata_area;
struct format_instance;
/* Per-format per-metadata area operations */
struct metadata_area_ops {
struct volume_group *(*vg_read) (struct format_instance * fi,
const char *vg_name,
struct metadata_area * mda);
struct volume_group *(*vg_read_precommit) (struct format_instance * fi,
const char *vg_name,
struct metadata_area * mda);
/*
* Write out complete VG metadata. You must ensure internal
* consistency before calling. eg. PEs can't refer to PVs not
* part of the VG.
*
* It is also the responsibility of the caller to ensure external
* consistency, eg by calling pv_write() if removing PVs from
* a VG or calling vg_write() a second time if splitting a VG
* into two.
*
* vg_write() should not read or write from any PVs not included
* in the volume_group structure it is handed.
* (format1 currently breaks this rule.)
*/
int (*vg_write) (struct format_instance * fid, struct volume_group * vg,
struct metadata_area * mda);
int (*vg_precommit) (struct format_instance * fid,
struct volume_group * vg,
struct metadata_area * mda);
int (*vg_commit) (struct format_instance * fid,
struct volume_group * vg, struct metadata_area * mda);
int (*vg_revert) (struct format_instance * fid,
struct volume_group * vg, struct metadata_area * mda);
int (*vg_remove) (struct format_instance * fi, struct volume_group * vg,
struct metadata_area * mda);
};
struct metadata_area {
struct list list;
struct metadata_area_ops *ops;
void *metadata_locn;
};
struct format_instance {
const struct format_type *fmt;
struct list metadata_areas; /* e.g. metadata locations */
void *private;
};
struct volume_group {
struct cmd_context *cmd;
struct format_instance *fid;
uint32_t seqno; /* Metadata sequence number */
struct id id;
char *name;
char *system_id;
uint32_t status;
alloc_policy_t alloc;
uint32_t extent_size;
uint32_t extent_count;
uint32_t free_count;
uint32_t max_lv;
uint32_t max_pv;
/* physical volumes */
uint32_t pv_count;
struct list pvs;
/* logical volumes */
uint32_t lv_count;
uint32_t snapshot_count;
struct list lvs;
struct list tags;
};
/* There will be one area for each stripe */
struct lv_segment_area {
area_type_t type;
union {
struct {
struct pv_segment *pvseg;
} pv;
struct {
struct logical_volume *lv;
uint32_t le;
} lv;
} u;
};
struct segment_type;
struct lv_segment {
struct list list;
struct logical_volume *lv;
struct segment_type *segtype;
uint32_t le;
uint32_t len;
uint32_t status;
/* FIXME Fields depend on segment type */
uint32_t stripe_size;
uint32_t area_count;
uint32_t area_len;
struct logical_volume *origin;
struct logical_volume *cow;
struct list origin_list;
uint32_t chunk_size; /* For snapshots - in sectors */
uint32_t region_size; /* For mirrors - in sectors */
uint32_t extents_copied;
struct logical_volume *log_lv;
struct lv_segment *mirror_seg;
struct list tags;
struct lv_segment_area *areas;
};
#define seg_type(seg, s) (seg)->areas[(s)].type
#define seg_pvseg(seg, s) (seg)->areas[(s)].u.pv.pvseg
#define seg_pv(seg, s) (seg)->areas[(s)].u.pv.pvseg->pv
#define seg_dev(seg, s) (seg)->areas[(s)].u.pv.pvseg->pv->dev
#define seg_pe(seg, s) (seg)->areas[(s)].u.pv.pvseg->pe
#define seg_lv(seg, s) (seg)->areas[(s)].u.lv.lv
#define seg_le(seg, s) (seg)->areas[(s)].u.lv.le
struct logical_volume {
union lvid lvid;
char *name;
struct volume_group *vg;
uint32_t status;
alloc_policy_t alloc;
uint32_t read_ahead;
int32_t major;
int32_t minor;
uint64_t size;
uint32_t le_count;
uint32_t origin_count;
struct list snapshot_segs;
struct lv_segment *snapshot;
struct list segments;
struct list tags;
};
struct name_list {
struct list list;
char *name;
};
struct pe_range {
struct list list;
uint32_t start; /* PEs */
uint32_t count; /* PEs */
};
struct pv_list {
struct list list;
struct physical_volume *pv;
struct list *mdas; /* Metadata areas */
struct list *pe_ranges; /* Ranges of PEs e.g. for allocation */
};
struct lv_list {
struct list list;
struct logical_volume *lv;
};
struct mda_list {
struct list list;
struct device_area mda;
};
struct peg_list {
struct list list;
struct pv_segment *peg;
};
/*
* Ownership of objects passes to caller.
*/
struct format_handler {
/*
* Scan any metadata areas that aren't referenced in PV labels
*/
int (*scan) (const struct format_type * fmt);
/*
* Return PV with given path.
*/
int (*pv_read) (const struct format_type * fmt, const char *pv_name,
struct physical_volume * pv, struct list * mdas);
/*
* Tweak an already filled out a pv ready for importing into a
* vg. eg. pe_count is format specific.
*/
int (*pv_setup) (const struct format_type * fmt,
uint64_t pe_start, uint32_t extent_count,
uint32_t extent_size,
int pvmetadatacopies,
uint64_t pvmetadatasize, struct list * mdas,
struct physical_volume * pv, struct volume_group * vg);
/*
* Write a PV structure to disk. Fails if the PV is in a VG ie
* pv->vg_name must be null.
*/
int (*pv_write) (const struct format_type * fmt,
struct physical_volume * pv, struct list * mdas,
int64_t label_sector);
/*
* Tweak an already filled out a lv eg, check there
* aren't too many extents.
*/
int (*lv_setup) (struct format_instance * fi,
struct logical_volume * lv);
/*
* Tweak an already filled out vg. eg, max_pv is format
* specific.
*/
int (*vg_setup) (struct format_instance * fi, struct volume_group * vg);
/*
* Check whether particular segment type is supported.
*/
int (*segtype_supported) (struct format_instance *fid,
struct segment_type *segtype);
/*
* Create format instance with a particular metadata area
*/
struct format_instance *(*create_instance) (const struct format_type *
fmt, const char *vgname,
const char *vgid,
void *context);
/*
* Destructor for format instance
*/
void (*destroy_instance) (struct format_instance * fid);
/*
* Destructor for format type
*/
void (*destroy) (const struct format_type * fmt);
};
/*
* Utility functions
*/
int vg_validate(struct volume_group *vg);
int vg_write(struct volume_group *vg);
int vg_commit(struct volume_group *vg);
int vg_revert(struct volume_group *vg);
struct volume_group *vg_read(struct cmd_context *cmd, const char *vg_name,
const char *vgid, int *consistent);
struct physical_volume *pv_read(struct cmd_context *cmd, const char *pv_name,
struct list *mdas, uint64_t *label_sector,
int warnings);
struct list *get_pvs(struct cmd_context *cmd);
/* Set full_scan to 1 to re-read every (filtered) device label */
struct list *get_vgs(struct cmd_context *cmd, int full_scan);
struct list *get_vgids(struct cmd_context *cmd, int full_scan);
int pv_write(struct cmd_context *cmd, struct physical_volume *pv,
struct list *mdas, int64_t label_sector);
/* pe_start and pe_end relate to any existing data so that new metadata
* areas can avoid overlap */
struct physical_volume *pv_create(const struct format_type *fmt,
struct device *dev,
struct id *id,
uint64_t size,
uint64_t pe_start,
uint32_t existing_extent_count,
uint32_t existing_extent_size,
int pvmetadatacopies,
uint64_t pvmetadatasize, struct list *mdas);
int pv_resize(struct physical_volume *pv, struct volume_group *vg,
uint32_t new_pe_count);
struct volume_group *vg_create(struct cmd_context *cmd, const char *name,
uint32_t extent_size, uint32_t max_pv,
uint32_t max_lv, alloc_policy_t alloc,
int pv_count, char **pv_names);
int vg_remove(struct volume_group *vg);
int vg_rename(struct cmd_context *cmd, struct volume_group *vg,
const char *new_name);
int vg_extend(struct format_instance *fi, struct volume_group *vg,
int pv_count, char **pv_names);
int vg_change_pesize(struct cmd_context *cmd, struct volume_group *vg,
uint32_t new_extent_size);
/* Manipulate LVs */
struct logical_volume *lv_create_empty(struct format_instance *fi,
const char *name,
union lvid *lvid,
uint32_t status,
alloc_policy_t alloc,
int import,
struct volume_group *vg);
/* Reduce the size of an LV by extents */
int lv_reduce(struct logical_volume *lv, uint32_t extents);
/* Empty an LV prior to deleting it */
int lv_empty(struct logical_volume *lv);
/* Entry point for all LV extent allocations */
int lv_extend(struct logical_volume *lv,
struct segment_type *segtype,
uint32_t stripes, uint32_t stripe_size,
uint32_t mirrors, uint32_t extents,
struct physical_volume *mirrored_pv, uint32_t mirrored_pe,
uint32_t status, struct list *allocatable_pvs,
alloc_policy_t alloc);
/* lv must be part of lv->vg->lvs */
int lv_remove(struct logical_volume *lv);
/* Manipulate PV structures */
int pv_add(struct volume_group *vg, struct physical_volume *pv);
int pv_remove(struct volume_group *vg, struct physical_volume *pv);
struct physical_volume *pv_find(struct volume_group *vg, const char *pv_name);
/* Find a PV within a given VG */
struct pv_list *find_pv_in_vg(struct volume_group *vg, const char *pv_name);
struct physical_volume *find_pv_in_vg_by_uuid(struct volume_group *vg,
struct id *id);
int get_pv_from_vg_by_id(const struct format_type *fmt, const char *vg_name,
const char *vgid, const char *pvid,
struct physical_volume *pv);
/* Find an LV within a given VG */
struct lv_list *find_lv_in_vg(struct volume_group *vg, const char *lv_name);
struct lv_list *find_lv_in_vg_by_lvid(struct volume_group *vg,
const union lvid *lvid);
/* Return the VG that contains a given LV (based on path given in lv_name) */
/* or environment var */
struct volume_group *find_vg_with_lv(const char *lv_name);
/* Find LV with given lvid (used during activation) */
struct logical_volume *lv_from_lvid(struct cmd_context *cmd,
const char *lvid_s,
int precommitted);
/* FIXME Merge these functions with ones above */
struct physical_volume *find_pv(struct volume_group *vg, struct device *dev);
struct logical_volume *find_lv(struct volume_group *vg, const char *lv_name);
struct physical_volume *find_pv_by_name(struct cmd_context *cmd,
const char *pv_name);
/* Find LV segment containing given LE */
struct lv_segment *find_seg_by_le(struct logical_volume *lv, uint32_t le);
struct lv_segment *first_seg(struct logical_volume *lv);
/* Find PV segment containing given LE */
struct pv_segment *find_peg_by_pe(struct physical_volume *pv, uint32_t pe);
/*
* Remove a dev_dir if present.
*/
const char *strip_dir(const char *vg_name, const char *dir);
/*
* Checks that an lv has no gaps or overlapping segments.
* Set complete_vg to perform additional VG level checks.
*/
int check_lv_segments(struct logical_volume *lv, int complete_vg);
/*
* Sometimes (eg, after an lvextend), it is possible to merge two
* adjacent segments into a single segment. This function trys
* to merge as many segments as possible.
*/
int lv_merge_segments(struct logical_volume *lv);
/*
* Ensure there's a segment boundary at a given LE, splitting if necessary
*/
int lv_split_segment(struct logical_volume *lv, uint32_t le);
/*
* Useful functions for managing snapshots.
*/
int lv_is_origin(const struct logical_volume *lv);
int lv_is_cow(const struct logical_volume *lv);
int lv_is_visible(const struct logical_volume *lv);
int pv_is_in_vg(struct volume_group *vg, struct physical_volume *pv);
/* Given a cow LV, return return the snapshot lv_segment that uses it */
struct lv_segment *find_cow(const struct logical_volume *lv);
/* Given a cow LV, return its origin */
struct logical_volume *origin_from_cow(const struct logical_volume *lv);
int vg_add_snapshot(struct format_instance *fid, const char *name,
struct logical_volume *origin, struct logical_volume *cow,
union lvid *lvid, uint32_t extent_count,
uint32_t chunk_size);
int vg_remove_snapshot(struct logical_volume *cow);
/*
* Mirroring functions
*/
struct alloc_handle;
uint32_t adjusted_mirror_region_size(uint32_t extent_size, uint32_t extents,
uint32_t region_size);
int create_mirror_layers(struct alloc_handle *ah,
uint32_t first_area,
uint32_t num_mirrors,
struct logical_volume *lv,
struct segment_type *segtype,
uint32_t status,
uint32_t region_size,
struct logical_volume *log_lv);
int add_mirror_layers(struct alloc_handle *ah,
uint32_t num_mirrors,
uint32_t existing_mirrors,
struct logical_volume *lv,
struct segment_type *segtype);
int remove_mirror_images(struct lv_segment *mirrored_seg, uint32_t num_mirrors,
struct list *removable_pvs, int remove_log);
/*
* Given mirror image or mirror log segment, find corresponding mirror segment
*/
struct lv_segment *find_mirror_seg(struct lv_segment *seg);
int fixup_imported_mirrors(struct volume_group *vg);
int insert_pvmove_mirrors(struct cmd_context *cmd,
struct logical_volume *lv_mirr,
struct list *source_pvl,
struct logical_volume *lv,
struct list *allocatable_pvs,
alloc_policy_t alloc,
struct list *lvs_changed);
int remove_pvmove_mirrors(struct volume_group *vg,
struct logical_volume *lv_mirr);
struct logical_volume *find_pvmove_lv(struct volume_group *vg,
struct device *dev, uint32_t lv_type);
struct logical_volume *find_pvmove_lv_from_pvname(struct cmd_context *cmd,
struct volume_group *vg,
const char *name,
uint32_t lv_type);
const char *get_pvmove_pvname_from_lv(struct logical_volume *lv);
const char *get_pvmove_pvname_from_lv_mirr(struct logical_volume *lv_mirr);
float copy_percent(struct logical_volume *lv_mirr);
struct list *lvs_using_lv(struct cmd_context *cmd, struct volume_group *vg,
struct logical_volume *lv);
uint32_t find_free_lvnum(struct logical_volume *lv);
char *generate_lv_name(struct volume_group *vg, const char *format,
char *buffer, size_t len);
#endif