1 /* $NetBSD: metadata.h,v 1.1.1.3 2009/12/02 00:25:43 haad Exp $ */ 2 3 /* 4 * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved. 5 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved. 6 * 7 * This file is part of LVM2. 8 * 9 * This copyrighted material is made available to anyone wishing to use, 10 * modify, copy, or redistribute it subject to the terms and conditions 11 * of the GNU Lesser General Public License v.2.1. 12 * 13 * You should have received a copy of the GNU Lesser General Public License 14 * along with this program; if not, write to the Free Software Foundation, 15 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 16 */ 17 18 /* 19 * This is the in core representation of a volume group and its 20 * associated physical and logical volumes. 21 */ 22 23 #ifndef _LVM_METADATA_H 24 #define _LVM_METADATA_H 25 26 #include "ctype.h" 27 #include "dev-cache.h" 28 #include "lvm-string.h" 29 #include "metadata-exported.h" 30 31 //#define MAX_STRIPES 128U 32 //#define SECTOR_SHIFT 9L 33 #define SECTOR_SIZE ( 1L << SECTOR_SHIFT ) 34 //#define STRIPE_SIZE_MIN ( (unsigned) lvm_getpagesize() >> SECTOR_SHIFT) /* PAGESIZE in sectors */ 35 //#define STRIPE_SIZE_MAX ( 512L * 1024L >> SECTOR_SHIFT) /* 512 KB in sectors */ 36 //#define STRIPE_SIZE_LIMIT ((UINT_MAX >> 2) + 1) 37 //#define PV_MIN_SIZE ( 512L * 1024L >> SECTOR_SHIFT) /* 512 KB in sectors */ 38 //#define MAX_RESTRICTED_LVS 255 /* Used by FMT_RESTRICTED_LVIDS */ 39 #define MIRROR_LOG_OFFSET 2 /* sectors */ 40 #define VG_MEMPOOL_CHUNK 10240 /* in bytes, hint only */ 41 42 /* 43 * Ceiling(n / sz) 44 */ 45 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 46 47 /* 48 * Ceiling(n / size) * size 49 */ 50 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 51 52 53 /* Various flags */ 54 /* Note that the bits no longer necessarily correspond to LVM1 disk format */ 55 56 //#define PARTIAL_VG 0x00000001U /* VG */ 57 //#define EXPORTED_VG 0x00000002U /* VG PV */ 58 //#define RESIZEABLE_VG 0x00000004U /* VG */ 59 60 /* May any free extents on this PV be used or must they be left free? */ 61 //#define ALLOCATABLE_PV 0x00000008U /* PV */ 62 63 #define SPINDOWN_LV 0x00000010U /* LV */ 64 #define BADBLOCK_ON 0x00000020U /* LV */ 65 //#define VISIBLE_LV 0x00000040U /* LV */ 66 //#define FIXED_MINOR 0x00000080U /* LV */ 67 /* FIXME Remove when metadata restructuring is completed */ 68 //#define SNAPSHOT 0x00001000U /* LV - internal use only */ 69 //#define PVMOVE 0x00002000U /* VG LV SEG */ 70 //#define LOCKED 0x00004000U /* LV */ 71 //#define MIRRORED 0x00008000U /* LV - internal use only */ 72 #define VIRTUAL 0x00010000U /* LV - internal use only */ 73 //#define MIRROR_LOG 0x00020000U /* LV */ 74 //#define MIRROR_IMAGE 0x00040000U /* LV */ 75 //#define MIRROR_NOTSYNCED 0x00080000U /* LV */ 76 #define ACTIVATE_EXCL 0x00100000U /* LV - internal use only */ 77 #define PRECOMMITTED 0x00200000U /* VG - internal use only */ 78 //#define CONVERTING 0x00400000U /* LV */ 79 80 //#define MISSING_PV 0x00800000U /* PV */ 81 //#define PARTIAL_LV 0x01000000U /* LV - derived flag, not 82 // written out in metadata*/ 83 84 #define POSTORDER_FLAG 0x02000000U /* Not real flags, reserved for */ 85 #define POSTORDER_OPEN_FLAG 0x04000000U /* temporary use inside vg_read_internal. */ 86 #define VIRTUAL_ORIGIN 0x08000000U /* LV - internal use only */ 87 88 //#define LVM_READ 0x00000100U /* LV VG */ 89 //#define LVM_WRITE 0x00000200U /* LV VG */ 90 //#define CLUSTERED 0x00000400U /* VG */ 91 #define SHARED 0x00000800U /* VG */ 92 93 /* Format features flags */ 94 //#define FMT_SEGMENTS 0x00000001U /* Arbitrary segment params? */ 95 //#define FMT_MDAS 0x00000002U /* Proper metadata areas? */ 96 //#define FMT_TAGS 0x00000004U /* Tagging? */ 97 //#define FMT_UNLIMITED_VOLS 0x00000008U /* Unlimited PVs/LVs? */ 98 //#define FMT_RESTRICTED_LVIDS 0x00000010U /* LVID <= 255 */ 99 //#define FMT_ORPHAN_ALLOCATABLE 0x00000020U /* Orphan PV allocatable? */ 100 #define FMT_PRECOMMIT 0x00000040U /* Supports pre-commit? */ 101 //#define FMT_RESIZE_PV 0x00000080U /* Supports pvresize? */ 102 //#define FMT_UNLIMITED_STRIPESIZE 0x00000100U /* Unlimited stripe size? */ 103 104 struct metadata_area; 105 106 /* Per-format per-metadata area operations */ 107 struct metadata_area_ops { 108 struct volume_group *(*vg_read) (struct format_instance * fi, 109 const char *vg_name, 110 struct metadata_area * mda); 111 struct volume_group *(*vg_read_precommit) (struct format_instance * fi, 112 const char *vg_name, 113 struct metadata_area * mda); 114 /* 115 * Write out complete VG metadata. You must ensure internal 116 * consistency before calling. eg. PEs can't refer to PVs not 117 * part of the VG. 118 * 119 * It is also the responsibility of the caller to ensure external 120 * consistency, eg by calling pv_write() if removing PVs from 121 * a VG or calling vg_write() a second time if splitting a VG 122 * into two. 123 * 124 * vg_write() should not read or write from any PVs not included 125 * in the volume_group structure it is handed. 126 * (format1 currently breaks this rule.) 127 */ 128 int (*vg_write) (struct format_instance * fid, struct volume_group * vg, 129 struct metadata_area * mda); 130 int (*vg_precommit) (struct format_instance * fid, 131 struct volume_group * vg, 132 struct metadata_area * mda); 133 int (*vg_commit) (struct format_instance * fid, 134 struct volume_group * vg, struct metadata_area * mda); 135 int (*vg_revert) (struct format_instance * fid, 136 struct volume_group * vg, struct metadata_area * mda); 137 int (*vg_remove) (struct format_instance * fi, struct volume_group * vg, 138 struct metadata_area * mda); 139 140 /* 141 * Returns number of free sectors in given metadata area. 142 */ 143 uint64_t (*mda_free_sectors) (struct metadata_area *mda); 144 145 /* 146 * Returns number of total sectors in given metadata area. 147 */ 148 uint64_t (*mda_total_sectors) (struct metadata_area *mda); 149 150 /* 151 * Check if metadata area belongs to vg 152 */ 153 int (*mda_in_vg) (struct format_instance * fi, 154 struct volume_group * vg, struct metadata_area *mda); 155 /* 156 * Analyze a metadata area on a PV. 157 */ 158 int (*pv_analyze_mda) (const struct format_type * fmt, 159 struct metadata_area *mda); 160 161 }; 162 163 struct metadata_area { 164 struct dm_list list; 165 struct metadata_area_ops *ops; 166 void *metadata_locn; 167 }; 168 169 #define seg_pvseg(seg, s) (seg)->areas[(s)].u.pv.pvseg 170 #define seg_dev(seg, s) (seg)->areas[(s)].u.pv.pvseg->pv->dev 171 #define seg_pe(seg, s) (seg)->areas[(s)].u.pv.pvseg->pe 172 #define seg_le(seg, s) (seg)->areas[(s)].u.lv.le 173 174 struct name_list { 175 struct dm_list list; 176 char *name; 177 }; 178 179 struct mda_list { 180 struct dm_list list; 181 struct device_area mda; 182 }; 183 184 struct peg_list { 185 struct dm_list list; 186 struct pv_segment *peg; 187 }; 188 189 struct seg_list { 190 struct dm_list list; 191 unsigned count; 192 struct lv_segment *seg; 193 }; 194 195 /* 196 * Ownership of objects passes to caller. 197 */ 198 struct format_handler { 199 /* 200 * Scan any metadata areas that aren't referenced in PV labels 201 */ 202 int (*scan) (const struct format_type * fmt); 203 204 /* 205 * Return PV with given path. 206 */ 207 int (*pv_read) (const struct format_type * fmt, const char *pv_name, 208 struct physical_volume * pv, struct dm_list *mdas, 209 int scan_label_only); 210 211 /* 212 * Tweak an already filled out a pv ready for importing into a 213 * vg. eg. pe_count is format specific. 214 */ 215 int (*pv_setup) (const struct format_type * fmt, 216 uint64_t pe_start, uint32_t extent_count, 217 uint32_t extent_size, unsigned long data_alignment, 218 unsigned long data_alignment_offset, 219 int pvmetadatacopies, 220 uint64_t pvmetadatasize, struct dm_list * mdas, 221 struct physical_volume * pv, struct volume_group * vg); 222 223 /* 224 * Write a PV structure to disk. Fails if the PV is in a VG ie 225 * pv->vg_name must be a valid orphan VG name 226 */ 227 int (*pv_write) (const struct format_type * fmt, 228 struct physical_volume * pv, struct dm_list * mdas, 229 int64_t label_sector); 230 231 /* 232 * Tweak an already filled out a lv eg, check there 233 * aren't too many extents. 234 */ 235 int (*lv_setup) (struct format_instance * fi, 236 struct logical_volume * lv); 237 238 /* 239 * Tweak an already filled out vg. eg, max_pv is format 240 * specific. 241 */ 242 int (*vg_setup) (struct format_instance * fi, struct volume_group * vg); 243 244 /* 245 * Check whether particular segment type is supported. 246 */ 247 int (*segtype_supported) (struct format_instance *fid, 248 const struct segment_type *segtype); 249 250 /* 251 * Create format instance with a particular metadata area 252 */ 253 struct format_instance *(*create_instance) (const struct format_type * 254 fmt, const char *vgname, 255 const char *vgid, 256 void *context); 257 258 /* 259 * Destructor for format instance 260 */ 261 void (*destroy_instance) (struct format_instance * fid); 262 263 /* 264 * Destructor for format type 265 */ 266 void (*destroy) (const struct format_type * fmt); 267 }; 268 269 /* 270 * Utility functions 271 */ 272 unsigned long set_pe_align(struct physical_volume *pv, unsigned long data_alignment); 273 unsigned long set_pe_align_offset(struct physical_volume *pv, 274 unsigned long data_alignment_offset); 275 int vg_validate(struct volume_group *vg); 276 277 int pv_write_orphan(struct cmd_context *cmd, struct physical_volume *pv); 278 279 /* Manipulate PV structures */ 280 int pv_add(struct volume_group *vg, struct physical_volume *pv); 281 int pv_remove(struct volume_group *vg, struct physical_volume *pv); 282 struct physical_volume *pv_find(struct volume_group *vg, const char *pv_name); 283 284 /* Find a PV within a given VG */ 285 int get_pv_from_vg_by_id(const struct format_type *fmt, const char *vg_name, 286 const char *vgid, const char *pvid, 287 struct physical_volume *pv); 288 289 struct lv_list *find_lv_in_vg_by_lvid(struct volume_group *vg, 290 const union lvid *lvid); 291 292 struct lv_list *find_lv_in_lv_list(const struct dm_list *ll, 293 const struct logical_volume *lv); 294 295 /* Return the VG that contains a given LV (based on path given in lv_name) */ 296 /* or environment var */ 297 struct volume_group *find_vg_with_lv(const char *lv_name); 298 299 /* Find LV with given lvid (used during activation) */ 300 struct logical_volume *lv_from_lvid(struct cmd_context *cmd, 301 const char *lvid_s, 302 unsigned precommitted); 303 304 /* FIXME Merge these functions with ones above */ 305 struct physical_volume *find_pv(struct volume_group *vg, struct device *dev); 306 307 struct pv_list *find_pv_in_pv_list(const struct dm_list *pl, 308 const struct physical_volume *pv); 309 310 /* Find LV segment containing given LE */ 311 struct lv_segment *find_seg_by_le(const struct logical_volume *lv, uint32_t le); 312 313 /* Find PV segment containing given LE */ 314 struct pv_segment *find_peg_by_pe(const struct physical_volume *pv, uint32_t pe); 315 316 /* 317 * Remove a dev_dir if present. 318 */ 319 const char *strip_dir(const char *vg_name, const char *dir); 320 321 struct logical_volume *alloc_lv(struct dm_pool *mem); 322 323 /* 324 * Checks that an lv has no gaps or overlapping segments. 325 * Set complete_vg to perform additional VG level checks. 326 */ 327 int check_lv_segments(struct logical_volume *lv, int complete_vg); 328 329 /* 330 * Sometimes (eg, after an lvextend), it is possible to merge two 331 * adjacent segments into a single segment. This function trys 332 * to merge as many segments as possible. 333 */ 334 int lv_merge_segments(struct logical_volume *lv); 335 336 /* 337 * Ensure there's a segment boundary at a given LE, splitting if necessary 338 */ 339 int lv_split_segment(struct logical_volume *lv, uint32_t le); 340 341 /* 342 * Add/remove upward link from underlying LV to the segment using it 343 * FIXME: ridiculously long name 344 */ 345 int add_seg_to_segs_using_this_lv(struct logical_volume *lv, struct lv_segment *seg); 346 int remove_seg_from_segs_using_this_lv(struct logical_volume *lv, struct lv_segment *seg); 347 struct lv_segment *get_only_segment_using_this_lv(struct logical_volume *lv); 348 349 /* 350 * Count snapshot LVs. 351 */ 352 unsigned snapshot_count(const struct volume_group *vg); 353 354 /* 355 * Calculate readahead from underlying PV devices 356 */ 357 void lv_calculate_readahead(const struct logical_volume *lv, uint32_t *read_ahead); 358 359 /* 360 * For internal metadata caching. 361 */ 362 int export_vg_to_buffer(struct volume_group *vg, char **buf); 363 struct volume_group *import_vg_from_buffer(char *buf, 364 struct format_instance *fid); 365 366 /* 367 * Mirroring functions 368 */ 369 370 /* 371 * Given mirror image or mirror log segment, find corresponding mirror segment 372 */ 373 int fixup_imported_mirrors(struct volume_group *vg); 374 375 /* 376 * Begin skeleton for external LVM library 377 */ 378 struct id pv_id(const struct physical_volume *pv); 379 const struct format_type *pv_format_type(const struct physical_volume *pv); 380 struct id pv_vgid(const struct physical_volume *pv); 381 382 struct physical_volume *pv_by_path(struct cmd_context *cmd, const char *pv_name); 383 int add_pv_to_vg(struct volume_group *vg, const char *pv_name, 384 struct physical_volume *pv); 385 386 #endif 387