mdadm.h

   1 /*
   2  * mdadm - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001-2009 Neil Brown <neilb@suse.de>
   5  *
   6  *
   7  *    This program is free software; you can redistribute it and/or modify
   8  *    it under the terms of the GNU General Public License as published by
   9  *    the Free Software Foundation; either version 2 of the License, or
  10  *    (at your option) any later version.
  11  *
  12  *    This program is distributed in the hope that it will be useful,
  13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *    GNU General Public License for more details.
  16  *
  17  *    You should have received a copy of the GNU General Public License
  18  *    along with this program; if not, write to the Free Software
  19  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  *    Author: Neil Brown
  22  *    Email: <neilb@suse.de>
  23  */
  24
  25 #define _GNU_SOURCE
  26 #define _FILE_OFFSET_BITS 64
  27 #include        <unistd.h>
  28 #if !defined(__dietlibc__) && !defined(__KLIBC__)
  29 extern __off64_t lseek64 __P ((int __fd, __off64_t __offset, int __whence));
  30 #else
  31 # if defined(__NO_STAT64) || __WORDSIZE != 32
  32 # define lseek64 lseek
  33 # endif
  34 #endif
  35
  36 #include        <sys/types.h>
  37 #include        <sys/stat.h>
  38 #include        <stdlib.h>
  39 #include        <time.h>
  40 #include        <sys/time.h>
  41 #include        <getopt.h>
  42 #include        <fcntl.h>
  43 #include        <stdio.h>
  44 #include        <errno.h>
  45 #include        <string.h>
  46 #include        <syslog.h>
  47 #ifdef __dietlibc__
  48 #include        <strings.h>
  49 /* dietlibc has deprecated random and srandom!! */
  50 #define random rand
  51 #define srandom srand
  52 #endif
  53
  54
  55 #include        <linux/kdev_t.h>
  56 /*#include      <linux/fs.h> */
  57 #include        <sys/mount.h>
  58 #include        <asm/types.h>
  59 #include        <sys/ioctl.h>
  60 #define MD_MAJOR 9
  61 #define MdpMinorShift 6
  62
  63 #ifndef BLKGETSIZE64
  64 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
  65 #endif
  66
  67 #define DEFAULT_CHUNK 512
  68 #define DEFAULT_BITMAP_CHUNK 4096
  69 #define DEFAULT_BITMAP_DELAY 5
  70 #define DEFAULT_MAX_WRITE_BEHIND 256
  71
  72 /* MAP_DIR should be somewhere that persists across the pivotroot
  73  * from early boot to late boot.
  74  * Currently /dev seems to be the only option on most distros.
  75  */
  76 #ifndef MAP_DIR
  77 #define MAP_DIR "/dev/.mdadm"
  78 #endif /* MAP_DIR */
  79 /* MAP_FILE is what we name the map file we put in MAP_DIR, in case you
  80  * want something other than the default of "map"
  81  */
  82 #ifndef MAP_FILE
  83 #define MAP_FILE "map"
  84 #endif /* MAP_FILE */
  85 /* MDMON_DIR is where pid and socket files used for communicating
  86  * with mdmon normally live.  It *should* be /var/run, but when
  87  * mdmon is needed at early boot then it needs to write there prior
  88  * to /var/run being mounted read/write, and it also then needs to
  89  * persist beyond when /var/run is mounter read-only.  So, to be
  90  * safe, the default is somewhere that is read/write early in the
  91  * boot process and stays up as long as possible during shutdown.
  92  */
  93 #ifndef MDMON_DIR
  94 #define MDMON_DIR "/dev/.mdadm/"
  95 #endif /* MDMON_DIR */
  96
  97 /* FAILED_SLOTS is where to save files storing recent removal of array
  98  * member in order to allow future reuse of disk inserted in the same
  99  * slot for array recovery
 100  */
 101 #ifndef FAILED_SLOTS_DIR
 102 #define FAILED_SLOTS_DIR "/dev/.mdadm/failed-slots"
 103 #endif /* FAILED_SLOTS */
 104
 105 #include        "md_u.h"
 106 #include        "md_p.h"
 107 #include        "bitmap.h"
 108 #include        "msg.h"
 109
 110 #include <endian.h>
 111 /* Redhat don't like to #include <asm/byteorder.h>, and
 112  * some time include <linux/byteorder/xxx_endian.h> isn't enough,
 113  * and there is no standard conversion function so... */
 114 /* And dietlibc doesn't think byteswap is ok, so.. */
 115 /*  #include <byteswap.h> */
 116 #define bswap_16(x) (((x) & 0x00ffU) << 8 | \
 117                      ((x) & 0xff00U) >> 8)
 118 #define bswap_32(x) (((x) & 0x000000ffU) << 24 | \
 119                      ((x) & 0xff000000U) >> 24 | \
 120                      ((x) & 0x0000ff00U) << 8  | \
 121                      ((x) & 0x00ff0000U) >> 8)
 122 #define bswap_64(x) (((x) & 0x00000000000000ffULL) << 56 | \
 123                      ((x) & 0xff00000000000000ULL) >> 56 | \
 124                      ((x) & 0x000000000000ff00ULL) << 40 | \
 125                      ((x) & 0x00ff000000000000ULL) >> 40 | \
 126                      ((x) & 0x0000000000ff0000ULL) << 24 | \
 127                      ((x) & 0x0000ff0000000000ULL) >> 24 | \
 128                      ((x) & 0x00000000ff000000ULL) << 8 | \
 129                      ((x) & 0x000000ff00000000ULL) >> 8)
 130
 131 #if !defined(__KLIBC__)
 132 #if BYTE_ORDER == LITTLE_ENDIAN
 133 #define __cpu_to_le16(_x) (_x)
 134 #define __cpu_to_le32(_x) (_x)
 135 #define __cpu_to_le64(_x) (_x)
 136 #define __le16_to_cpu(_x) (_x)
 137 #define __le32_to_cpu(_x) (_x)
 138 #define __le64_to_cpu(_x) (_x)
 139
 140 #define __cpu_to_be16(_x) bswap_16(_x)
 141 #define __cpu_to_be32(_x) bswap_32(_x)
 142 #define __cpu_to_be64(_x) bswap_64(_x)
 143 #define __be16_to_cpu(_x) bswap_16(_x)
 144 #define __be32_to_cpu(_x) bswap_32(_x)
 145 #define __be64_to_cpu(_x) bswap_64(_x)
 146 #elif BYTE_ORDER == BIG_ENDIAN
 147 #define __cpu_to_le16(_x) bswap_16(_x)
 148 #define __cpu_to_le32(_x) bswap_32(_x)
 149 #define __cpu_to_le64(_x) bswap_64(_x)
 150 #define __le16_to_cpu(_x) bswap_16(_x)
 151 #define __le32_to_cpu(_x) bswap_32(_x)
 152 #define __le64_to_cpu(_x) bswap_64(_x)
 153
 154 #define __cpu_to_be16(_x) (_x)
 155 #define __cpu_to_be32(_x) (_x)
 156 #define __cpu_to_be64(_x) (_x)
 157 #define __be16_to_cpu(_x) (_x)
 158 #define __be32_to_cpu(_x) (_x)
 159 #define __be64_to_cpu(_x) (_x)
 160 #else
 161 #  error "unknown endianness."
 162 #endif
 163 #endif /* __KLIBC__ */
 164
 165
 166 /*
 167  * min()/max()/clamp() macros that also do
 168  * strict type-checking.. See the
 169  * "unnecessary" pointer comparison.
 170  */
 171 #define min(x, y) ({                            \
 172         typeof(x) _min1 = (x);                  \
 173         typeof(y) _min2 = (y);                  \
 174         (void) (&_min1 == &_min2);              \
 175         _min1 < _min2 ? _min1 : _min2; })
 176
 177 #define max(x, y) ({                            \
 178         typeof(x) _max1 = (x);                  \
 179         typeof(y) _max2 = (y);                  \
 180         (void) (&_max1 == &_max2);              \
 181         _max1 > _max2 ? _max1 : _max2; })
 182
 183 /* general information that might be extracted from a superblock */
 184 struct mdinfo {
 185         mdu_array_info_t        array;
 186         mdu_disk_info_t         disk;
 187         __u64                   events;
 188         int                     uuid[4];
 189         char                    name[33];
 190         unsigned long long      data_offset;
 191         unsigned long long      component_size; /* same as array.size, except in
 192                                                  * sectors and up to 64bits.
 193                                                  */
 194         unsigned long long      custom_array_size; /* size for non-default sized
 195                                                     * arrays (in sectors)
 196                                                     */
 197         int                     reshape_active;
 198         unsigned long long      reshape_progress;
 199         union {
 200                 unsigned long long resync_start; /* per-array resync position */
 201                 unsigned long long recovery_start; /* per-device rebuild position */
 202                 #define MaxSector  (~0ULL) /* resync/recovery complete position */
 203         };
 204         unsigned long           safe_mode_delay; /* ms delay to mark clean */
 205         int                     new_level, delta_disks, new_layout, new_chunk;
 206         int                     errors;
 207         unsigned long           cache_size; /* size of raid456 stripe cache*/
 208         int                     mismatch_cnt;
 209         char                    text_version[50];
 210         void                    *update_private; /* for passing metadata-format
 211                                                   * specific update data
 212                                                   * between successive calls to
 213                                                   * update_super()
 214                                                   */
 215
 216         int container_member; /* for assembling external-metatdata arrays
 217                                * This is to be used internally by metadata
 218                                * handler only */
 219         int container_enough; /* flag external handlers can set to
 220                                * indicate that subarrays have not enough (-1),
 221                                * enough to start (0), or all expected disks (1) */
 222         char            sys_name[20];
 223         struct mdinfo *devs;
 224         struct mdinfo *next;
 225
 226         /* Device info for mdmon: */
 227         int recovery_fd;
 228         int state_fd;
 229         #define DS_FAULTY       1
 230         #define DS_INSYNC       2
 231         #define DS_WRITE_MOSTLY 4
 232         #define DS_SPARE        8
 233         #define DS_BLOCKED      16
 234         #define DS_REMOVE       1024
 235         #define DS_UNBLOCK      2048
 236         int prev_state, curr_state, next_state;
 237
 238 };
 239
 240 struct createinfo {
 241         int     uid;
 242         int     gid;
 243         int     autof;
 244         int     mode;
 245         int     symlinks;
 246         struct supertype *supertype;
 247 };
 248
 249 #define Name "mdadm"
 250
 251 enum mode {
 252         ASSEMBLE=1,
 253         BUILD,
 254         CREATE,
 255         MANAGE,
 256         MISC,
 257         MONITOR,
 258         GROW,
 259         INCREMENTAL,
 260         AUTODETECT,
 261 };
 262
 263 extern char short_options[];
 264 extern char short_bitmap_options[];
 265 extern char short_bitmap_auto_options[];
 266 extern struct option long_options[];
 267 extern char Version[], Usage[], Help[], OptionHelp[],
 268         Help_create[], Help_build[], Help_assemble[], Help_grow[],
 269         Help_incr[],
 270         Help_manage[], Help_misc[], Help_monitor[], Help_config[];
 271
 272 /* for option that don't have short equivilents, we assign arbitrary
 273  * numbers later than any 'short' character option.
 274  */
 275 enum special_options {
 276         AssumeClean = 300,
 277         BitmapChunk,
 278         WriteBehind,
 279         ReAdd,
 280         NoDegraded,
 281         Sparc22,
 282         BackupFile,
 283         HomeHost,
 284         AutoHomeHost,
 285         Symlinks,
 286         AutoDetect,
 287         Waitclean,
 288         DetailPlatform,
 289         KillSubarray,
 290         UpdateSubarray,
 291         IncrementalPath,
 292         NoSharing,
 293         HelpOptions,
 294         Brief,
 295         ManageOpt,
 296         Add,
 297         Remove,
 298         Fail,
 299         MiscOpt,
 300         WaitOpt,
 301         ConfigFile,
 302         ChunkSize,
 303         WriteMostly,
 304         Layout,
 305         Auto,
 306         Force,
 307         SuperMinor,
 308         EMail,
 309         ProgramOpt,
 310         Increment,
 311         Fork,
 312         Bitmap,
 313         RebuildMapOpt,
 314         InvalidBackup,
 315         UdevRules,
 316 };
 317
 318 /* structures read from config file */
 319 /* List of mddevice names and identifiers
 320  * Identifiers can be:
 321  *    uuid=128-hex-uuid
 322  *    super-minor=decimal-minor-number-from-superblock
 323  *    devices=comma,separated,list,of,device,names,with,wildcards
 324  *
 325  * If multiple fields are present, the intersection of all matching
 326  * devices is considered
 327  */
 328 #define UnSet (0xfffe)
 329 struct mddev_ident {
 330         char    *devname;
 331
 332         int     uuid_set;
 333         int     uuid[4];
 334         char    name[33];
 335
 336         int super_minor;
 337
 338         char    *devices;       /* comma separated list of device
 339                                  * names with wild cards
 340                                  */
 341         int     level;
 342         int raid_disks;
 343         int spare_disks;
 344         struct supertype *st;
 345         int     autof;          /* 1 for normal, 2 for partitioned */
 346         char    *spare_group;
 347         char    *bitmap_file;
 348         int     bitmap_fd;
 349
 350         char    *container;     /* /dev/whatever name of container, or
 351                                  * uuid of container.  You would expect
 352                                  * this to be the 'devname' or UUID
 353                                  * of some other entry.
 354                                  */
 355         char    *member;        /* subarray within a container */
 356
 357         struct mddev_ident *next;
 358         union {
 359                 /* fields needed by different users of this structure */
 360                 int assembled;  /* set when assembly succeeds */
 361         };
 362 };
 363
 364 /* List of device names - wildcards expanded */
 365 struct mddev_dev {
 366         char *devname;
 367         int disposition;        /* 'a' for add, 'r' for remove, 'f' for fail.
 368                                  * Not set for names read from .config
 369                                  */
 370         char writemostly;       /* 1 for 'set writemostly', 2 for 'clear writemostly' */
 371         char re_add;
 372         char used;              /* set when used */
 373         struct mddev_dev *next;
 374 };
 375
 376 typedef struct mapping {
 377         char *name;
 378         int num;
 379 } mapping_t;
 380
 381
 382 struct mdstat_ent {
 383         char            *dev;
 384         int             devnum;
 385         int             active;
 386         char            *level;
 387         char            *pattern; /* U or up, _ for down */
 388         int             percent; /* -1 if no resync */
 389         int             resync; /* 3 if check, 2 if reshape, 1 if resync, 0 if recovery */
 390         int             devcnt;
 391         int             raid_disks;
 392         char *          metadata_version;
 393         struct dev_member {
 394                 char                    *name;
 395                 struct dev_member       *next;
 396         }               *members;
 397         struct mdstat_ent *next;
 398 };
 399
 400 extern struct mdstat_ent *mdstat_read(int hold, int start);
 401 extern void free_mdstat(struct mdstat_ent *ms);
 402 extern void mdstat_wait(int seconds);
 403 extern void mdstat_wait_fd(int fd, const sigset_t *sigmask);
 404 extern int mddev_busy(int devnum);
 405 extern struct mdstat_ent *mdstat_by_component(char *name);
 406 extern struct mdstat_ent *mdstat_by_subdev(char *subdev, int container);
 407
 408 struct map_ent {
 409         struct map_ent *next;
 410         int     devnum;
 411         char    metadata[20];
 412         int     uuid[4];
 413         int     bad;
 414         char    *path;
 415 };
 416 extern int map_update(struct map_ent **mpp, int devnum, char *metadata,
 417                       int uuid[4], char *path);
 418 extern void map_remove(struct map_ent **map, int devnum);
 419 extern struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4]);
 420 extern struct map_ent *map_by_devnum(struct map_ent **map, int devnum);
 421 extern struct map_ent *map_by_name(struct map_ent **map, char *name);
 422 extern void map_read(struct map_ent **melp);
 423 extern int map_write(struct map_ent *mel);
 424 extern void map_delete(struct map_ent **mapp, int devnum);
 425 extern void map_free(struct map_ent *map);
 426 extern void map_add(struct map_ent **melp,
 427                     int devnum, char *metadata, int uuid[4], char *path);
 428 extern int map_lock(struct map_ent **melp);
 429 extern void map_unlock(struct map_ent **melp);
 430
 431 /* various details can be requested */
 432 enum sysfs_read_flags {
 433         GET_LEVEL       = (1 << 0),
 434         GET_LAYOUT      = (1 << 1),
 435         GET_COMPONENT   = (1 << 2),
 436         GET_CHUNK       = (1 << 3),
 437         GET_CACHE       = (1 << 4),
 438         GET_MISMATCH    = (1 << 5),
 439         GET_VERSION     = (1 << 6),
 440         GET_DISKS       = (1 << 7),
 441         GET_DEGRADED    = (1 << 8),
 442         GET_SAFEMODE    = (1 << 9),
 443         GET_DEVS        = (1 << 10), /* gets role, major, minor */
 444         GET_OFFSET      = (1 << 11),
 445         GET_SIZE        = (1 << 12),
 446         GET_STATE       = (1 << 13),
 447         GET_ERROR       = (1 << 14),
 448 };
 449
 450 /* If fd >= 0, get the array it is open on,
 451  * else use devnum. >=0 -> major9. <0.....
 452  */
 453 extern int sysfs_open(int devnum, char *devname, char *attr);
 454 extern void sysfs_init(struct mdinfo *mdi, int fd, int devnum);
 455 extern void sysfs_free(struct mdinfo *sra);
 456 extern struct mdinfo *sysfs_read(int fd, int devnum, unsigned long options);
 457 extern int sysfs_attr_match(const char *attr, const char *str);
 458 extern int sysfs_match_word(const char *word, char **list);
 459 extern int sysfs_set_str(struct mdinfo *sra, struct mdinfo *dev,
 460                          char *name, char *val);
 461 extern int sysfs_set_num(struct mdinfo *sra, struct mdinfo *dev,
 462                          char *name, unsigned long long val);
 463 extern int sysfs_uevent(struct mdinfo *sra, char *event);
 464 extern int sysfs_get_fd(struct mdinfo *sra, struct mdinfo *dev,
 465                         char *name);
 466 extern int sysfs_fd_get_ll(int fd, unsigned long long *val);
 467 extern int sysfs_get_ll(struct mdinfo *sra, struct mdinfo *dev,
 468                         char *name, unsigned long long *val);
 469 extern int sysfs_fd_get_str(int fd, char *val, int size);
 470 extern int sysfs_attribute_available(struct mdinfo *sra, struct mdinfo *dev,
 471                                      char *name);
 472 extern int sysfs_get_str(struct mdinfo *sra, struct mdinfo *dev,
 473                          char *name, char *val, int size);
 474 extern int sysfs_set_safemode(struct mdinfo *sra, unsigned long ms);
 475 extern int sysfs_set_array(struct mdinfo *info, int vers);
 476 extern int sysfs_add_disk(struct mdinfo *sra, struct mdinfo *sd, int resume);
 477 extern int sysfs_disk_to_scsi_id(int fd, __u32 *id);
 478 extern int sysfs_unique_holder(int devnum, long rdev);
 479 extern int sysfs_freeze_array(struct mdinfo *sra);
 480 extern int load_sys(char *path, char *buf);
 481 extern int reshape_prepare_fdlist(char *devname,
 482                                   struct mdinfo *sra,
 483                                   int raid_disks,
 484                                   int nrdisks,
 485                                   unsigned long blocks,
 486                                   char *backup_file,
 487                                   int *fdlist,
 488                                   unsigned long long *offsets);
 489 extern void reshape_free_fdlist(int *fdlist,
 490                                 unsigned long long *offsets,
 491                                 int size);
 492 extern int reshape_open_backup_file(char *backup,
 493                                     int fd,
 494                                     char *devname,
 495                                     long blocks,
 496                                     int *fdlist,
 497                                     unsigned long long *offsets,
 498                                     int restart);
 499 extern unsigned long compute_backup_blocks(int nchunk, int ochunk,
 500                                            unsigned int ndata, unsigned int odata);
 501
 502 extern int save_stripes(int *source, unsigned long long *offsets,
 503                         int raid_disks, int chunk_size, int level, int layout,
 504                         int nwrites, int *dest,
 505                         unsigned long long start, unsigned long long length,
 506                         char *buf);
 507 extern int restore_stripes(int *dest, unsigned long long *offsets,
 508                            int raid_disks, int chunk_size, int level, int layout,
 509                            int source, unsigned long long read_offset,
 510                            unsigned long long start, unsigned long long length,
 511                            char *src_buf);
 512
 513 #ifndef Sendmail
 514 #define Sendmail "/usr/lib/sendmail -t"
 515 #endif
 516
 517 #define SYSLOG_FACILITY LOG_DAEMON
 518
 519 extern char *map_num(mapping_t *map, int num);
 520 extern int map_name(mapping_t *map, char *name);
 521 extern mapping_t r5layout[], r6layout[], pers[], modes[], faultylayout[];
 522
 523 extern char *map_dev(int major, int minor, int create);
 524
 525 struct active_array;
 526 struct metadata_update;
 527
 528
 529 /* 'struct reshape' records the intermediate states
 530  * a general reshape.
 531  * The starting geometry is converted to the 'before' geometry
 532  * by at most an atomic level change. They could be the same.
 533  * Similarly the 'after' geometry is converted to the final
 534  * geometry by at most a level change.
 535  * Note that 'before' and 'after' must have the same level.
 536  * 'blocks' is the minimum number of sectors for a reshape unit.
 537  * This will be a multiple of the stripe size in each of the
 538  * 'before' and 'after' geometries.
 539  * If 'blocks' is 0, no restriping is necessary.
 540  */
 541 struct reshape {
 542         int level;
 543         int parity; /* number of parity blocks/devices */
 544         struct {
 545                 int layout;
 546                 int data_disks;
 547         } before, after;
 548         unsigned long long backup_blocks;
 549         unsigned long long stripes; /* number of old stripes that comprise 'blocks'*/
 550         unsigned long long new_size; /* New size of array in sectors */
 551 };
 552
 553 /* A superswitch provides entry point the a metadata handler.
 554  *
 555  * The super_switch primarily operates on some "metadata" that
 556  * is accessed via the 'supertype'.
 557  * This metadata has one of three possible sources.
 558  * 1/ It is read from a single device.  In this case it may not completely
 559  *    describe the array or arrays as some information might be on other
 560  *    devices.
 561  * 2/ It is read from all devices in a container.  In this case all
 562  *    information is present.
 563  * 3/ It is created by ->init_super / ->add_to_super.  In this case it will
 564  *    be complete once enough ->add_to_super calls have completed.
 565  *
 566  * When creating an array inside a container, the metadata will be
 567  * formed by a combination of 2 and 3.  The metadata or the array is read,
 568  * then new information is added.
 569  *
 570  * The metadata must sometimes have a concept of a 'current' array
 571  * and a 'current' device.
 572  * The 'current' array is set by init_super to be the newly created array,
 573  * or is set by super_by_fd when it finds it is looking at an array inside
 574  * a container.
 575  *
 576  * The 'current' device is either the device that the metadata was read from
 577  * in case 1, or the last device added by add_to_super in case 3.
 578  * Case 2 does not identify a 'current' device.
 579  */
 580 extern struct superswitch {
 581
 582         /* Used to report details of metadata read from a component
 583          * device. ->load_super has been called.
 584          */
 585         void (*examine_super)(struct supertype *st, char *homehost);
 586         void (*brief_examine_super)(struct supertype *st, int verbose);
 587         void (*brief_examine_subarrays)(struct supertype *st, int verbose);
 588         void (*export_examine_super)(struct supertype *st);
 589
 590         /* Used to report details of an active array.
 591          * ->load_super was possibly given a 'component' string.
 592          */
 593         void (*detail_super)(struct supertype *st, char *homehost);
 594         void (*brief_detail_super)(struct supertype *st);
 595         void (*export_detail_super)(struct supertype *st);
 596
 597         /* Optional: platform hardware / firmware details */
 598         int (*detail_platform)(int verbose, int enumerate_only);
 599
 600         /* Used:
 601          *   to get uuid to storing in bitmap metadata
 602          *   and 'reshape' backup-data metadata
 603          *   To see if a device is being re-added to an array it was part of.
 604          */
 605         void (*uuid_from_super)(struct supertype *st, int uuid[4]);
 606
 607         /* Extract generic details from metadata.  This could be details about
 608          * the container, or about an individual array within the container.
 609          * The determination is made either by:
 610          *   load_super being given a 'component' string.
 611          *   validate_geometry determining what to create.
 612          * The info includes both array information and device information.
 613          * The particular device should be:
 614          *   The last device added by add_to_super
 615          *   The device the metadata was loaded from by load_super
 616          * If 'map' is present, then it is an array raid_disks long
 617          * (raid_disk must already be set and correct) and it is filled
 618          * with 1 for slots that are thought to be active and 0 for slots which
 619          * appear to be failed/missing.
 620          * *info is zeroed out before data is added.
 621          */
 622         void (*getinfo_super)(struct supertype *st, struct mdinfo *info, char *map);
 623         struct mdinfo *(*getinfo_super_disks)(struct supertype *st);
 624         /* Check if the given metadata is flagged as belonging to "this"
 625          * host.  0 for 'no', 1 for 'yes', -1 for "Don't record homehost"
 626          */
 627         int (*match_home)(struct supertype *st, char *homehost);
 628
 629         /* Make one of several generic modifications to metadata
 630          * prior to assembly (or other times).
 631          *   sparc2.2  - first bug in early 0.90 metadata
 632          *   super-minor - change name of 0.90 metadata
 633          *   summaries - 'correct' any redundant data
 634          *   resync - mark array as dirty to trigger a resync.
 635          *   uuid - set new uuid - only 0.90 or 1.x
 636          *   name - change the name of the array (where supported)
 637          *   homehost - change which host this array is tied to.
 638          *   devicesize - If metadata is at start of device, change recorded
 639          *               device size to match actual device size
 640          *   byteorder - swap bytes for 0.90 metadata
 641          *
 642          *   force-one  - mark that device as uptodate, not old or failed.
 643          *   force-array - mark array as clean if it would not otherwise
 644          *               assemble
 645          *   assemble   - not sure how this is different from force-one...
 646          *   linear-grow-new - add a new device to a linear array, but don't
 647          *                   change the size: so superblock still matches
 648          *   linear-grow-update - now change the size of the array.
 649          *   writemostly - set the WriteMostly1 bit in the superblock devflags
 650          *   readwrite - clear the WriteMostly1 bit in the superblock devflags
 651          */
 652         int (*update_super)(struct supertype *st, struct mdinfo *info,
 653                             char *update,
 654                             char *devname, int verbose,
 655                             int uuid_set, char *homehost);
 656
 657         /* Create new metadata for new array as described.  This could
 658          * be a new container, or an array in a pre-existing container.
 659          * Also used to zero metadata prior to writing it to invalidate old
 660          * metadata.
 661          */
 662         int (*init_super)(struct supertype *st, mdu_array_info_t *info,
 663                           unsigned long long size, char *name,
 664                           char *homehost, int *uuid);
 665
 666         /* update the metadata to include new device, either at create or
 667          * when hot-adding a spare.
 668          */
 669         int (*add_to_super)(struct supertype *st, mdu_disk_info_t *dinfo,
 670                             int fd, char *devname);
 671         /* update the metadata to delete a device,
 672          * when hot-removing.
 673          */
 674         int (*remove_from_super)(struct supertype *st, mdu_disk_info_t *dinfo);
 675
 676         /* Write metadata to one device when fixing problems or adding
 677          * a new device.
 678          */
 679         int (*store_super)(struct supertype *st, int fd);
 680
 681         /*  Write all metadata for this array.
 682          */
 683         int (*write_init_super)(struct supertype *st);
 684         int (*compare_super)(struct supertype *st, struct supertype *tst);
 685         int (*load_super)(struct supertype *st, int fd, char *devname);
 686         int (*load_container)(struct supertype *st, int fd, char *devname);
 687         struct supertype * (*match_metadata_desc)(char *arg);
 688         __u64 (*avail_size)(struct supertype *st, __u64 size);
 689         unsigned long long (*min_acceptable_spare_size)(struct supertype *st);
 690         int (*add_internal_bitmap)(struct supertype *st, int *chunkp,
 691                                    int delay, int write_behind,
 692                                    unsigned long long size, int may_change, int major);
 693         void (*locate_bitmap)(struct supertype *st, int fd);
 694         int (*write_bitmap)(struct supertype *st, int fd);
 695         void (*free_super)(struct supertype *st);
 696
 697         /* validate_geometry is called with an st returned by
 698          * match_metadata_desc.
 699          * It should check that the geometry described in compatible with
 700          * the metadata type.  It will be called repeatedly as devices
 701          * added to validate changing size and new devices.  If there are
 702          * inter-device dependencies, it should record sufficient details
 703          * so these can be validated.
 704          * Both 'size' and '*freesize' are in sectors.  chunk is KiB.
 705          * Return value is:
 706          *  1: everything is OK
 707          *  0: not OK for some reason - if 'verbose', then error was reported.
 708          * -1: st->sb was NULL, 'subdev' is a member of a container of this
 709          *     types, but array is not acceptable for some reason
 710          *     message was reported even if verbose is 0.
 711          */
 712         int (*validate_geometry)(struct supertype *st, int level, int layout,
 713                                  int raiddisks,
 714                                  int *chunk, unsigned long long size,
 715                                  char *subdev, unsigned long long *freesize,
 716                                  int verbose);
 717
 718         struct mdinfo *(*container_content)(struct supertype *st, char *subarray);
 719         /* query the supertype for default geometry */
 720         void (*default_geometry)(struct supertype *st, int *level, int *layout, int *chunk); /* optional */
 721         /* Permit subarray's to be deleted from inactive containers */
 722         int (*kill_subarray)(struct supertype *st); /* optional */
 723         /* Permit subarray's to be modified */
 724         int (*update_subarray)(struct supertype *st, char *subarray,
 725                                char *update, struct mddev_ident *ident); /* optional */
 726         /* Check if reshape is supported for this external format.
 727          * st is obtained from super_by_fd() where st->subarray[0] is
 728          * initialized to indicate if reshape is being performed at the
 729          * container or subarray level
 730          */
 731         int (*reshape_super)(struct supertype *st, long long size, int level,
 732                              int layout, int chunksize, int raid_disks,
 733                              int delta_disks, char *backup, char *dev,
 734                              int verbose); /* optional */
 735         int (*manage_reshape)( /* optional */
 736                 int afd, struct mdinfo *sra, struct reshape *reshape,
 737                 struct supertype *st, unsigned long blocks,
 738                 int *fds, unsigned long long *offsets,
 739                 int dests, int *destfd, unsigned long long *destoffsets);
 740
 741 /* for mdmon */
 742         int (*open_new)(struct supertype *c, struct active_array *a,
 743                         char *inst);
 744
 745         /* Tell the metadata handler the current state of the array.
 746          * This covers whether it is known to be consistent (no pending writes)
 747          * and how far along a resync is known to have progressed
 748          * (in a->resync_start).
 749          * resync status is really irrelevant if the array is not consistent,
 750          * but some metadata (DDF!) have a place to record the distinction.
 751          * If 'consistent' is '2', then the array can mark it dirty if a
 752          * resync/recovery/whatever is required, or leave it clean if not.
 753          * Return value is 0 dirty (not consistent) and 1 if clean.
 754          * it is only really important if consistent is passed in as '2'.
 755          */
 756         int (*set_array_state)(struct active_array *a, int consistent);
 757
 758         /* When the state of a device might have changed, we call set_disk to
 759          * tell the metadata what the current state is.
 760          * Typically this happens on spare->in_sync and (spare|in_sync)->faulty
 761          * transitions.
 762          * set_disk might be called when the state of the particular disk has
 763          * not in fact changed.
 764          */
 765         void (*set_disk)(struct active_array *a, int n, int state);
 766         void (*sync_metadata)(struct supertype *st);
 767         void (*process_update)(struct supertype *st,
 768                                struct metadata_update *update);
 769         void (*prepare_update)(struct supertype *st,
 770                                struct metadata_update *update);
 771
 772         /* activate_spare will check if the array is degraded and, if it
 773          * is, try to find some spare space in the container.
 774          * On success, it add appropriate updates (For process_update) to
 775          * to the 'updates' list and returns a list of 'mdinfo' identifying
 776          * the device, or devices as there might be multiple missing
 777          * devices and multiple spares available.
 778          */
 779         struct mdinfo *(*activate_spare)(struct active_array *a,
 780                                          struct metadata_update **updates);
 781         /*
 782          * Return statically allocated string that represents metadata specific
 783          * controller domain of the disk. The domain is used in disk domain
 784          * matching functions. Disks belong to the same domain if the they have
 785          * the same domain from mdadm.conf and belong the same metadata domain.
 786          * Returning NULL or not providing this handler means that metadata
 787          * does not distinguish the differences between disks that belong to
 788          * different controllers. They are in the domain specified by
 789          * configuration file (mdadm.conf).
 790          * In case when the metadata has the notion of domains based on disk
 791          * it shall return NULL for disks that do not belong to the controller
 792          * the supported domains. Such disks will form another domain and won't
 793          * be mixed with supported ones.
 794          */
 795         const char *(*get_disk_controller_domain)(const char *path);
 796
 797         /* for external backup area */
 798         int (*recover_backup)(struct supertype *st, struct mdinfo *info);
 799
 800         int swapuuid; /* true if uuid is bigending rather than hostendian */
 801         int external;
 802         const char *name; /* canonical metadata name */
 803 } *superlist[];
 804
 805 extern struct superswitch super0, super1;
 806 extern struct superswitch super_imsm, super_ddf;
 807 extern struct superswitch mbr, gpt;
 808
 809 struct metadata_update {
 810         int     len;
 811         char    *buf;
 812         void    *space; /* allocated space that monitor will use */
 813         void    **space_list; /* list of allocated spaces that monitor can
 814                                * use or that it returned.
 815                                */
 816         struct metadata_update *next;
 817 };
 818
 819 /* A supertype holds a particular collection of metadata.
 820  * It identifies the metadata type by the superswitch, and the particular
 821  * sub-version of that metadata type.
 822  * metadata read in or created is stored in 'sb' and 'info'.
 823  * There are also fields used by mdmon to track containers.
 824  *
 825  * A supertype may refer to:
 826  *   Just an array, possibly in a container
 827  *   A container, not identifying any particular array
 828  *   Info read from just one device, not yet fully describing the array/container.
 829  *
 830  *
 831  * A supertype is created by:
 832  *   super_by_fd
 833  *   guess_super
 834  *   dup_super
 835  */
 836 struct supertype {
 837         struct superswitch *ss;
 838         int minor_version;
 839         int max_devs;
 840         int container_dev;    /* devnum of container */
 841         void *sb;
 842         void *info;
 843         int ignore_hw_compat; /* used to inform metadata handlers that it should ignore
 844                                  HW/firmware related incompatability to load metadata.
 845                                  Used when examining metadata to display content of disk
 846                                  when user has no hw/firmare compatible system.
 847                               */
 848         struct metadata_update *updates;
 849         struct metadata_update **update_tail;
 850
 851         /* extra stuff used by mdmon */
 852         struct active_array *arrays;
 853         int sock; /* listen to external programs */
 854         int devnum;
 855         char *devname; /* e.g. md0.  This appears in metadata_verison:
 856                         *  external:/md0/12
 857                         */
 858         int devcnt;
 859
 860         struct mdinfo *devs;
 861
 862 };
 863
 864 extern struct supertype *super_by_fd(int fd, char **subarray);
 865 enum guess_types { guess_any, guess_array, guess_partitions };
 866 extern struct supertype *guess_super_type(int fd, enum guess_types guess_type);
 867 static inline struct supertype *guess_super(int fd) {
 868         return guess_super_type(fd, guess_any);
 869 }
 870 extern struct supertype *dup_super(struct supertype *st);
 871 extern int get_dev_size(int fd, char *dname, unsigned long long *sizep);
 872 extern int must_be_container(int fd);
 873 extern int dev_size_from_id(dev_t id, unsigned long long *size);
 874 extern void get_one_disk(int mdfd, mdu_array_info_t *ainf,
 875                          mdu_disk_info_t *disk);
 876 void wait_for(char *dev, int fd);
 877
 878 /*
 879  * Data structures for policy management.
 880  * Each device can have a policy structure that lists
 881  * various name/value pairs each possibly with a metadata associated.
 882  * The policy list is sorted by name/value/metadata
 883  */
 884 struct dev_policy {
 885         struct dev_policy *next;
 886         char *name;     /* None of these strings are allocated.  They are
 887                          * all just references to strings which are known
 888                          * to exist elsewhere.
 889                          * name and metadata can be compared by address equality.
 890                          */
 891         const char *metadata;
 892         const char *value;
 893 };
 894
 895 extern char pol_act[], pol_domain[], pol_metadata[], pol_auto[];
 896
 897 /* iterate over the sublist starting at list, having the same
 898  * 'name' as 'list', and matching the given metadata (Where
 899  * NULL matches anything
 900  */
 901 #define pol_for_each(item, list, _metadata)                             \
 902         for (item = list;                                               \
 903              item && item->name == list->name;                          \
 904              item = item->next)                                         \
 905                 if (!(!_metadata || !item->metadata || _metadata == item->metadata)) \
 906                         ; else
 907
 908 /*
 909  * policy records read from mdadm are largely just name-value pairs.
 910  * The names are constants, not strdupped
 911  */
 912 struct pol_rule {
 913         struct pol_rule *next;
 914         char *type;     /* rule_policy or rule_part */
 915         struct rule {
 916                 struct rule *next;
 917                 char *name;
 918                 char *value;
 919                 char *dups; /* duplicates of 'value' with a partNN appended */
 920         } *rule;
 921 };
 922
 923 extern char rule_policy[], rule_part[];
 924 extern char rule_path[], rule_type[];
 925 extern char type_part[], type_disk[];
 926
 927 extern void policyline(char *line, char *type);
 928 extern void policy_add(char *type, ...);
 929 extern void policy_free(void);
 930
 931 extern struct dev_policy *path_policy(char *path, char *type);
 932 extern struct dev_policy *disk_policy(struct mdinfo *disk);
 933 extern struct dev_policy *devnum_policy(int dev);
 934 extern void dev_policy_free(struct dev_policy *p);
 935
 936 //extern void pol_new(struct dev_policy **pol, char *name, char *val, char *metadata);
 937 extern void pol_add(struct dev_policy **pol, char *name, char *val, char *metadata);
 938 extern struct dev_policy *pol_find(struct dev_policy *pol, char *name);
 939
 940 enum policy_action {
 941         act_default,
 942         act_include,
 943         act_re_add,
 944         act_spare,      /* This only applies to bare devices */
 945         act_spare_same_slot, /* this allows non-bare devices,
 946                               * but only if recent removal */
 947         act_force_spare, /* this allow non-bare devices in any case */
 948         act_err
 949 };
 950
 951 extern int policy_action_allows(struct dev_policy *plist, const char *metadata,
 952                                 enum policy_action want);
 953 extern int disk_action_allows(struct mdinfo *disk, const char *metadata,
 954                               enum policy_action want);
 955
 956 struct domainlist {
 957         struct domainlist *next;
 958         const char *dom;
 959 };
 960
 961 extern int domain_test(struct domainlist *dom, struct dev_policy *pol,
 962                        const char *metadata);
 963 extern struct domainlist *domain_from_array(struct mdinfo *mdi,
 964                                             const char *metadata);
 965 extern void domainlist_add_dev(struct domainlist **dom, int devnum,
 966                                const char *metadata);
 967 extern void domain_free(struct domainlist *dl);
 968 extern void domain_merge(struct domainlist **domp, struct dev_policy *pol,
 969                          const char *metadata);
 970 void domain_add(struct domainlist **domp, char *domain);
 971
 972 extern void policy_save_path(char *id_path, struct map_ent *array);
 973 extern int policy_check_path(struct mdinfo *disk, struct map_ent *array);
 974
 975 #if __GNUC__ < 3
 976 struct stat64;
 977 #endif
 978
 979 #define HAVE_NFTW  we assume
 980 #define HAVE_FTW
 981
 982 #ifdef __UCLIBC__
 983 # include <features.h>
 984 # ifndef __UCLIBC_HAS_LFS__
 985 #  define lseek64 lseek
 986 # endif
 987 # ifndef  __UCLIBC_HAS_FTW__
 988 #  undef HAVE_FTW
 989 #  undef HAVE_NFTW
 990 # endif
 991 #endif
 992
 993 #ifdef __dietlibc__
 994 # undef HAVE_NFTW
 995 #endif
 996
 997 #if defined(__KLIBC__)
 998 # undef HAVE_NFTW
 999 # undef HAVE_FTW
1000 #endif
1001
1002 #ifndef HAVE_NFTW
1003 # define FTW_PHYS 1
1004 # ifndef HAVE_FTW
1005   struct FTW {};
1006 # endif
1007 #endif
1008
1009 #ifdef HAVE_FTW
1010 # include <ftw.h>
1011 #endif
1012
1013 extern int add_dev(const char *name, const struct stat *stb, int flag, struct FTW *s);
1014
1015
1016 extern int Manage_ro(char *devname, int fd, int readonly);
1017 extern int Manage_runstop(char *devname, int fd, int runstop, int quiet);
1018 extern int Manage_resize(char *devname, int fd, long long size, int raid_disks);
1019 extern int Manage_subdevs(char *devname, int fd,
1020                           struct mddev_dev *devlist, int verbose, int test,
1021                           char *update, int force);
1022 extern int autodetect(void);
1023 extern int Grow_Add_device(char *devname, int fd, char *newdev);
1024 extern int Grow_addbitmap(char *devname, int fd, char *file, int chunk, int delay, int write_behind, int force);
1025 extern int Grow_reshape(char *devname, int fd, int quiet, char *backup_file,
1026                         long long size,
1027                         int level, char *layout_str, int chunksize, int raid_disks,
1028                         struct mddev_dev *devlist,
1029                         int assume_clean, int force);
1030 extern int Grow_restart(struct supertype *st, struct mdinfo *info,
1031                         int *fdlist, int cnt, char *backup_file, int verbose);
1032 extern int Grow_continue(int mdfd, struct supertype *st,
1033                          struct mdinfo *info, char *backup_file);
1034 extern int restore_backup(struct supertype *st,
1035                           struct mdinfo *content,
1036                           int working_disks,
1037                           int spares,
1038                           char *backup_file,
1039                           int verbose);
1040
1041 extern int Assemble(struct supertype *st, char *mddev,
1042                     struct mddev_ident *ident,
1043                     struct mddev_dev *devlist,
1044                     char *backup_file, int invalid_backup,
1045                     int readonly, int runstop,
1046                     char *update, char *homehost, int require_homehost,
1047                     int verbose, int force);
1048
1049 extern int Build(char *mddev, int chunk, int level, int layout,
1050                  int raiddisks, struct mddev_dev *devlist, int assume_clean,
1051                  char *bitmap_file, int bitmap_chunk, int write_behind,
1052                  int delay, int verbose, int autof, unsigned long long size);
1053
1054
1055 extern int Create(struct supertype *st, char *mddev,
1056                   int chunk, int level, int layout, unsigned long long size, int raiddisks, int sparedisks,
1057                   char *name, char *homehost, int *uuid,
1058                   int subdevs, struct mddev_dev *devlist,
1059                   int runstop, int verbose, int force, int assume_clean,
1060                   char *bitmap_file, int bitmap_chunk, int write_behind, int delay, int autof);
1061
1062 extern int Detail(char *dev, int brief, int export, int test, char *homehost);
1063 extern int Detail_Platform(struct superswitch *ss, int scan, int verbose);
1064 extern int Query(char *dev);
1065 extern int Examine(struct mddev_dev *devlist, int brief, int export, int scan,
1066                    int SparcAdjust, struct supertype *forcest, char *homehost);
1067 extern int Monitor(struct mddev_dev *devlist,
1068                    char *mailaddr, char *alert_cmd,
1069                    int period, int daemonise, int scan, int oneshot,
1070                    int dosyslog, int test, char *pidfile, int increments,
1071                    int share);
1072
1073 extern int Kill(char *dev, struct supertype *st, int force, int quiet, int noexcl);
1074 extern int Kill_subarray(char *dev, char *subarray, int quiet);
1075 extern int Update_subarray(char *dev, char *subarray, char *update, struct mddev_ident *ident, int quiet);
1076 extern int Wait(char *dev);
1077 extern int WaitClean(char *dev, int sock, int verbose);
1078
1079 extern int Incremental(char *devname, int verbose, int runstop,
1080                        struct supertype *st, char *homehost, int require_homehost,
1081                        int autof);
1082 extern void RebuildMap(void);
1083 extern int IncrementalScan(int verbose);
1084 extern int IncrementalRemove(char *devname, char *path, int verbose);
1085 extern int CreateBitmap(char *filename, int force, char uuid[16],
1086                         unsigned long chunksize, unsigned long daemon_sleep,
1087                         unsigned long write_behind,
1088                         unsigned long long array_size,
1089                         int major);
1090 extern int ExamineBitmap(char *filename, int brief, struct supertype *st);
1091 extern int Write_rules(char *rule_name);
1092 extern int bitmap_update_uuid(int fd, int *uuid, int swap);
1093 extern unsigned long bitmap_sectors(struct bitmap_super_s *bsb);
1094
1095 extern int md_get_version(int fd);
1096 extern int get_linux_version(void);
1097 extern int mdadm_version(char *version);
1098 extern long long parse_size(char *size);
1099 extern int parse_uuid(char *str, int uuid[4]);
1100 extern int parse_layout_10(char *layout);
1101 extern int parse_layout_faulty(char *layout);
1102 extern int check_ext2(int fd, char *name);
1103 extern int check_reiser(int fd, char *name);
1104 extern int check_raid(int fd, char *name);
1105 extern int check_partitions(int fd, char *dname,
1106                             unsigned long long freesize,
1107                             unsigned long long size);
1108
1109 extern int get_mdp_major(void);
1110 extern int dev_open(char *dev, int flags);
1111 extern int open_dev(int devnum);
1112 extern int open_dev_flags(int devnum, int flags);
1113 extern int open_dev_excl(int devnum);
1114 extern int is_standard(char *dev, int *nump);
1115 extern int same_dev(char *one, char *two);
1116
1117 extern int parse_auto(char *str, char *msg, int config);
1118 extern struct mddev_ident *conf_get_ident(char *dev);
1119 extern struct mddev_dev *conf_get_devs(void);
1120 extern int conf_test_dev(char *devname);
1121 extern int conf_test_metadata(const char *version, struct dev_policy *pol, int is_homehost);
1122 extern struct createinfo *conf_get_create_info(void);
1123 extern void set_conffile(char *file);
1124 extern char *conf_get_mailaddr(void);
1125 extern char *conf_get_mailfrom(void);
1126 extern char *conf_get_program(void);
1127 extern char *conf_get_homehost(int *require_homehostp);
1128 extern char *conf_line(FILE *file);
1129 extern char *conf_word(FILE *file, int allow_key);
1130 extern int conf_name_is_free(char *name);
1131 extern int devname_matches(char *name, char *match);
1132 extern struct mddev_ident *conf_match(struct mdinfo *info, struct supertype *st);
1133 extern int experimental(void);
1134
1135 extern void free_line(char *line);
1136 extern int match_oneof(char *devices, char *devname);
1137 extern void uuid_from_super(int uuid[4], mdp_super_t *super);
1138 extern const int uuid_zero[4];
1139 extern int same_uuid(int a[4], int b[4], int swapuuid);
1140 extern void copy_uuid(void *a, int b[4], int swapuuid);
1141 extern char *__fname_from_uuid(int id[4], int swap, char *buf, char sep);
1142 extern char *fname_from_uuid(struct supertype *st,
1143                              struct mdinfo *info, char *buf, char sep);
1144 extern unsigned long calc_csum(void *super, int bytes);
1145 extern int enough(int level, int raid_disks, int layout, int clean,
1146                    char *avail, int avail_disks);
1147 extern int enough_fd(int fd);
1148 extern int ask(char *mesg);
1149 extern unsigned long long get_component_size(int fd);
1150 extern void remove_partitions(int fd);
1151 extern int test_partition(int fd);
1152 extern int test_partition_from_id(dev_t id);
1153 extern unsigned long long calc_array_size(int level, int raid_disks, int layout,
1154                                    int chunksize, unsigned long long devsize);
1155 extern int flush_metadata_updates(struct supertype *st);
1156 extern void append_metadata_update(struct supertype *st, void *buf, int len);
1157 extern int assemble_container_content(struct supertype *st, int mdfd,
1158                                       struct mdinfo *content, int runstop,
1159                                       char *chosen_name, int verbose,
1160                                       char *backup_file);
1161 extern struct mdinfo *container_choose_spares(struct supertype *st,
1162                                               unsigned long long min_size,
1163                                               struct domainlist *domlist,
1164                                               char *spare_group,
1165                                               const char *metadata, int get_one);
1166 extern int move_spare(char *from_devname, char *to_devname, dev_t devid);
1167 extern int add_disk(int mdfd, struct supertype *st,
1168                     struct mdinfo *sra, struct mdinfo *info);
1169 extern int remove_disk(int mdfd, struct supertype *st,
1170                        struct mdinfo *sra, struct mdinfo *info);
1171 extern int set_array_info(int mdfd, struct supertype *st, struct mdinfo *info);
1172 unsigned long long min_recovery_start(struct mdinfo *array);
1173
1174 extern char *human_size(long long bytes);
1175 extern char *human_size_brief(long long bytes);
1176 extern void print_r10_layout(int layout);
1177
1178 #define NoMdDev (1<<23)
1179 extern int find_free_devnum(int use_partitions);
1180
1181 extern void put_md_name(char *name);
1182 extern char *get_md_name(int dev);
1183
1184 extern char DefaultConfFile[];
1185
1186 extern int create_mddev(char *dev, char *name, int autof, int trustworthy,
1187                         char *chosen);
1188 /* values for 'trustworthy' */
1189 #define LOCAL   1
1190 #define LOCAL_ANY 10
1191 #define FOREIGN 2
1192 #define METADATA 3
1193 extern int open_mddev(char *dev, int report_errors);
1194 extern int open_container(int fd);
1195 extern int is_container_member(struct mdstat_ent *ent, char *devname);
1196 extern int is_subarray_active(char *subarray, char *devname);
1197 extern int open_subarray(char *dev, char *subarray, struct supertype *st, int quiet);
1198 extern struct superswitch *version_to_superswitch(char *vers);
1199
1200 extern int mdmon_running(int devnum);
1201 extern int mdmon_pid(int devnum);
1202 extern int check_env(char *name);
1203 extern __u32 random32(void);
1204 extern int start_mdmon(int devnum);
1205
1206 extern int child_monitor(int afd, struct mdinfo *sra, struct reshape *reshape,
1207                          struct supertype *st, unsigned long stripes,
1208                          int *fds, unsigned long long *offsets,
1209                          int dests, int *destfd, unsigned long long *destoffsets);
1210 void abort_reshape(struct mdinfo *sra);
1211
1212 extern char *devnum2devname(int num);
1213 extern void fmt_devname(char *name, int num);
1214 extern int devname2devnum(char *name);
1215 extern int stat2devnum(struct stat *st);
1216 extern int fd2devnum(int fd);
1217
1218 static inline int dev2major(int d)
1219 {
1220         if (d >= 0)
1221                 return MD_MAJOR;
1222         else
1223                 return get_mdp_major();
1224 }
1225
1226 static inline int dev2minor(int d)
1227 {
1228         if (d >= 0)
1229                 return d;
1230         return (-1-d) << MdpMinorShift;
1231 }
1232
1233 static inline int ROUND_UP(int a, int base)
1234 {
1235         return ((a+base-1)/base)*base;
1236 }
1237
1238 static inline int is_subarray(char *vers)
1239 {
1240         /* The version string for a 'subarray' (an array in a container)
1241          * is
1242          *    /containername/componentname    for normal read-write arrays
1243          *    -containername/componentname    for arrays which mdmon must not
1244          *                                    reconfigure.  They might be read-only
1245          *                                    or might be undergoing reshape etc.
1246          * containername is e.g. md0, md_d1
1247          * componentname is dependant on the metadata. e.g. '1' 'S1' ...
1248          */
1249         return (*vers == '/' || *vers == '-');
1250 }
1251
1252 static inline char *to_subarray(struct mdstat_ent *ent, char *container)
1253 {
1254         return &ent->metadata_version[10+strlen(container)+1];
1255 }
1256
1257 #ifdef DEBUG
1258 #define dprintf(fmt, arg...) \
1259         fprintf(stderr, fmt, ##arg)
1260 #else
1261 #define dprintf(fmt, arg...) \
1262         ({ if (0) fprintf(stderr, fmt, ##arg); 0; })
1263 #endif
1264 #include <assert.h>
1265 #include <stdarg.h>
1266 static inline int xasprintf(char **strp, const char *fmt, ...) {
1267         va_list ap;
1268         int ret;
1269         va_start(ap, fmt);
1270         ret = vasprintf(strp, fmt, ap);
1271         va_end(ap);
1272         assert(ret >= 0);
1273         return ret;
1274 }
1275
1276 #define LEVEL_MULTIPATH         (-4)
1277 #define LEVEL_LINEAR            (-1)
1278 #define LEVEL_FAULTY            (-5)
1279
1280 /* kernel module doesn't know about these */
1281 #define LEVEL_CONTAINER         (-100)
1282 #define LEVEL_UNSUPPORTED       (-200)
1283
1284
1285 /* faulty stuff */
1286
1287 #define WriteTransient  0
1288 #define ReadTransient   1
1289 #define WritePersistent 2
1290 #define ReadPersistent  3
1291 #define WriteAll        4 /* doesn't go to device */
1292 #define ReadFixable     5
1293 #define Modes   6
1294
1295 #define ClearErrors     31
1296 #define ClearFaults     30
1297
1298 #define AllPersist      100 /* internal use only */
1299 #define NoPersist       101
1300
1301 #define ModeMask        0x1f
1302 #define ModeShift       5
1303
1304
1305 #ifdef __TINYC__
1306 #undef minor
1307 #undef major
1308 #undef makedev
1309 #define minor(x) ((x)&0xff)
1310 #define major(x) (((x)>>8)&0xff)
1311 #define makedev(M,m) (((M)<<8) | (m))
1312 #endif
1313
1314 /* for raid4/5/6 */
1315 #define ALGORITHM_LEFT_ASYMMETRIC       0
1316 #define ALGORITHM_RIGHT_ASYMMETRIC      1
1317 #define ALGORITHM_LEFT_SYMMETRIC        2
1318 #define ALGORITHM_RIGHT_SYMMETRIC       3
1319
1320 /* Define non-rotating (raid4) algorithms.  These allow
1321  * conversion of raid4 to raid5.
1322  */
1323 #define ALGORITHM_PARITY_0              4 /* P or P,Q are initial devices */
1324 #define ALGORITHM_PARITY_N              5 /* P or P,Q are final devices. */
1325
1326 /* DDF RAID6 layouts differ from md/raid6 layouts in two ways.
1327  * Firstly, the exact positioning of the parity block is slightly
1328  * different between the 'LEFT_*' modes of md and the "_N_*" modes
1329  * of DDF.
1330  * Secondly, or order of datablocks over which the Q syndrome is computed
1331  * is different.
1332  * Consequently we have different layouts for DDF/raid6 than md/raid6.
1333  * These layouts are from the DDFv1.2 spec.
1334  * Interestingly DDFv1.2-Errata-A does not specify N_CONTINUE but
1335  * leaves RLQ=3 as 'Vendor Specific'
1336  */
1337
1338 #define ALGORITHM_ROTATING_ZERO_RESTART 8 /* DDF PRL=6 RLQ=1 */
1339 #define ALGORITHM_ROTATING_N_RESTART    9 /* DDF PRL=6 RLQ=2 */
1340 #define ALGORITHM_ROTATING_N_CONTINUE   10 /*DDF PRL=6 RLQ=3 */
1341
1342
1343 /* For every RAID5 algorithm we define a RAID6 algorithm
1344  * with exactly the same layout for data and parity, and
1345  * with the Q block always on the last device (N-1).
1346  * This allows trivial conversion from RAID5 to RAID6
1347  */
1348 #define ALGORITHM_LEFT_ASYMMETRIC_6     16
1349 #define ALGORITHM_RIGHT_ASYMMETRIC_6    17
1350 #define ALGORITHM_LEFT_SYMMETRIC_6      18
1351 #define ALGORITHM_RIGHT_SYMMETRIC_6     19
1352 #define ALGORITHM_PARITY_0_6            20
1353 #define ALGORITHM_PARITY_N_6            ALGORITHM_PARITY_N
1354
1355 /* Define PATH_MAX in case we don't use glibc or standard library does
1356  * not have PATH_MAX defined. Assume max path length is 4K characters.
1357  */
1358 #ifndef PATH_MAX
1359 #define PATH_MAX        4096
1360 #endif
1361
1362 #define PROCESS_DELAYED -2
1363 #define PROCESS_PENDING -3