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v5.4
 
   1/*
   2 * Copyright (C) 2010-2011 Neil Brown
   3 * Copyright (C) 2010-2018 Red Hat, Inc. All rights reserved.
   4 *
   5 * This file is released under the GPL.
   6 */
   7
   8#include <linux/slab.h>
   9#include <linux/module.h>
  10
  11#include "md.h"
  12#include "raid1.h"
  13#include "raid5.h"
  14#include "raid10.h"
  15#include "md-bitmap.h"
  16
  17#include <linux/device-mapper.h>
  18
  19#define DM_MSG_PREFIX "raid"
  20#define	MAX_RAID_DEVICES	253 /* md-raid kernel limit */
  21
  22/*
  23 * Minimum sectors of free reshape space per raid device
  24 */
  25#define	MIN_FREE_RESHAPE_SPACE to_sector(4*4096)
  26
  27/*
  28 * Minimum journal space 4 MiB in sectors.
  29 */
  30#define	MIN_RAID456_JOURNAL_SPACE (4*2048)
  31
  32static bool devices_handle_discard_safely = false;
  33
  34/*
  35 * The following flags are used by dm-raid.c to set up the array state.
  36 * They must be cleared before md_run is called.
  37 */
  38#define FirstUse 10		/* rdev flag */
  39
  40struct raid_dev {
  41	/*
  42	 * Two DM devices, one to hold metadata and one to hold the
  43	 * actual data/parity.	The reason for this is to not confuse
  44	 * ti->len and give more flexibility in altering size and
  45	 * characteristics.
  46	 *
  47	 * While it is possible for this device to be associated
  48	 * with a different physical device than the data_dev, it
  49	 * is intended for it to be the same.
  50	 *    |--------- Physical Device ---------|
  51	 *    |- meta_dev -|------ data_dev ------|
  52	 */
  53	struct dm_dev *meta_dev;
  54	struct dm_dev *data_dev;
  55	struct md_rdev rdev;
  56};
  57
  58/*
  59 * Bits for establishing rs->ctr_flags
  60 *
  61 * 1 = no flag value
  62 * 2 = flag with value
  63 */
  64#define __CTR_FLAG_SYNC			0  /* 1 */ /* Not with raid0! */
  65#define __CTR_FLAG_NOSYNC		1  /* 1 */ /* Not with raid0! */
  66#define __CTR_FLAG_REBUILD		2  /* 2 */ /* Not with raid0! */
  67#define __CTR_FLAG_DAEMON_SLEEP		3  /* 2 */ /* Not with raid0! */
  68#define __CTR_FLAG_MIN_RECOVERY_RATE	4  /* 2 */ /* Not with raid0! */
  69#define __CTR_FLAG_MAX_RECOVERY_RATE	5  /* 2 */ /* Not with raid0! */
  70#define __CTR_FLAG_MAX_WRITE_BEHIND	6  /* 2 */ /* Only with raid1! */
  71#define __CTR_FLAG_WRITE_MOSTLY		7  /* 2 */ /* Only with raid1! */
  72#define __CTR_FLAG_STRIPE_CACHE		8  /* 2 */ /* Only with raid4/5/6! */
  73#define __CTR_FLAG_REGION_SIZE		9  /* 2 */ /* Not with raid0! */
  74#define __CTR_FLAG_RAID10_COPIES	10 /* 2 */ /* Only with raid10 */
  75#define __CTR_FLAG_RAID10_FORMAT	11 /* 2 */ /* Only with raid10 */
  76/* New for v1.9.0 */
  77#define __CTR_FLAG_DELTA_DISKS		12 /* 2 */ /* Only with reshapable raid1/4/5/6/10! */
  78#define __CTR_FLAG_DATA_OFFSET		13 /* 2 */ /* Only with reshapable raid4/5/6/10! */
  79#define __CTR_FLAG_RAID10_USE_NEAR_SETS 14 /* 2 */ /* Only with raid10! */
  80
  81/* New for v1.10.0 */
  82#define __CTR_FLAG_JOURNAL_DEV		15 /* 2 */ /* Only with raid4/5/6 (journal device)! */
  83
  84/* New for v1.11.1 */
  85#define __CTR_FLAG_JOURNAL_MODE		16 /* 2 */ /* Only with raid4/5/6 (journal mode)! */
  86
  87/*
  88 * Flags for rs->ctr_flags field.
  89 */
  90#define CTR_FLAG_SYNC			(1 << __CTR_FLAG_SYNC)
  91#define CTR_FLAG_NOSYNC			(1 << __CTR_FLAG_NOSYNC)
  92#define CTR_FLAG_REBUILD		(1 << __CTR_FLAG_REBUILD)
  93#define CTR_FLAG_DAEMON_SLEEP		(1 << __CTR_FLAG_DAEMON_SLEEP)
  94#define CTR_FLAG_MIN_RECOVERY_RATE	(1 << __CTR_FLAG_MIN_RECOVERY_RATE)
  95#define CTR_FLAG_MAX_RECOVERY_RATE	(1 << __CTR_FLAG_MAX_RECOVERY_RATE)
  96#define CTR_FLAG_MAX_WRITE_BEHIND	(1 << __CTR_FLAG_MAX_WRITE_BEHIND)
  97#define CTR_FLAG_WRITE_MOSTLY		(1 << __CTR_FLAG_WRITE_MOSTLY)
  98#define CTR_FLAG_STRIPE_CACHE		(1 << __CTR_FLAG_STRIPE_CACHE)
  99#define CTR_FLAG_REGION_SIZE		(1 << __CTR_FLAG_REGION_SIZE)
 100#define CTR_FLAG_RAID10_COPIES		(1 << __CTR_FLAG_RAID10_COPIES)
 101#define CTR_FLAG_RAID10_FORMAT		(1 << __CTR_FLAG_RAID10_FORMAT)
 102#define CTR_FLAG_DELTA_DISKS		(1 << __CTR_FLAG_DELTA_DISKS)
 103#define CTR_FLAG_DATA_OFFSET		(1 << __CTR_FLAG_DATA_OFFSET)
 104#define CTR_FLAG_RAID10_USE_NEAR_SETS	(1 << __CTR_FLAG_RAID10_USE_NEAR_SETS)
 105#define CTR_FLAG_JOURNAL_DEV		(1 << __CTR_FLAG_JOURNAL_DEV)
 106#define CTR_FLAG_JOURNAL_MODE		(1 << __CTR_FLAG_JOURNAL_MODE)
 107
 108/*
 109 * Definitions of various constructor flags to
 110 * be used in checks of valid / invalid flags
 111 * per raid level.
 112 */
 113/* Define all any sync flags */
 114#define	CTR_FLAGS_ANY_SYNC		(CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)
 115
 116/* Define flags for options without argument (e.g. 'nosync') */
 117#define	CTR_FLAG_OPTIONS_NO_ARGS	(CTR_FLAGS_ANY_SYNC | \
 118					 CTR_FLAG_RAID10_USE_NEAR_SETS)
 119
 120/* Define flags for options with one argument (e.g. 'delta_disks +2') */
 121#define CTR_FLAG_OPTIONS_ONE_ARG (CTR_FLAG_REBUILD | \
 122				  CTR_FLAG_WRITE_MOSTLY | \
 123				  CTR_FLAG_DAEMON_SLEEP | \
 124				  CTR_FLAG_MIN_RECOVERY_RATE | \
 125				  CTR_FLAG_MAX_RECOVERY_RATE | \
 126				  CTR_FLAG_MAX_WRITE_BEHIND | \
 127				  CTR_FLAG_STRIPE_CACHE | \
 128				  CTR_FLAG_REGION_SIZE | \
 129				  CTR_FLAG_RAID10_COPIES | \
 130				  CTR_FLAG_RAID10_FORMAT | \
 131				  CTR_FLAG_DELTA_DISKS | \
 132				  CTR_FLAG_DATA_OFFSET)
 
 
 133
 134/* Valid options definitions per raid level... */
 135
 136/* "raid0" does only accept data offset */
 137#define RAID0_VALID_FLAGS	(CTR_FLAG_DATA_OFFSET)
 138
 139/* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */
 140#define RAID1_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 141				 CTR_FLAG_REBUILD | \
 142				 CTR_FLAG_WRITE_MOSTLY | \
 143				 CTR_FLAG_DAEMON_SLEEP | \
 144				 CTR_FLAG_MIN_RECOVERY_RATE | \
 145				 CTR_FLAG_MAX_RECOVERY_RATE | \
 146				 CTR_FLAG_MAX_WRITE_BEHIND | \
 147				 CTR_FLAG_REGION_SIZE | \
 148				 CTR_FLAG_DELTA_DISKS | \
 149				 CTR_FLAG_DATA_OFFSET)
 150
 151/* "raid10" does not accept any raid1 or stripe cache options */
 152#define RAID10_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 153				 CTR_FLAG_REBUILD | \
 154				 CTR_FLAG_DAEMON_SLEEP | \
 155				 CTR_FLAG_MIN_RECOVERY_RATE | \
 156				 CTR_FLAG_MAX_RECOVERY_RATE | \
 157				 CTR_FLAG_REGION_SIZE | \
 158				 CTR_FLAG_RAID10_COPIES | \
 159				 CTR_FLAG_RAID10_FORMAT | \
 160				 CTR_FLAG_DELTA_DISKS | \
 161				 CTR_FLAG_DATA_OFFSET | \
 162				 CTR_FLAG_RAID10_USE_NEAR_SETS)
 163
 164/*
 165 * "raid4/5/6" do not accept any raid1 or raid10 specific options
 166 *
 167 * "raid6" does not accept "nosync", because it is not guaranteed
 168 * that both parity and q-syndrome are being written properly with
 169 * any writes
 170 */
 171#define RAID45_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 172				 CTR_FLAG_REBUILD | \
 173				 CTR_FLAG_DAEMON_SLEEP | \
 174				 CTR_FLAG_MIN_RECOVERY_RATE | \
 175				 CTR_FLAG_MAX_RECOVERY_RATE | \
 176				 CTR_FLAG_STRIPE_CACHE | \
 177				 CTR_FLAG_REGION_SIZE | \
 178				 CTR_FLAG_DELTA_DISKS | \
 179				 CTR_FLAG_DATA_OFFSET | \
 180				 CTR_FLAG_JOURNAL_DEV | \
 181				 CTR_FLAG_JOURNAL_MODE)
 182
 183#define RAID6_VALID_FLAGS	(CTR_FLAG_SYNC | \
 184				 CTR_FLAG_REBUILD | \
 185				 CTR_FLAG_DAEMON_SLEEP | \
 186				 CTR_FLAG_MIN_RECOVERY_RATE | \
 187				 CTR_FLAG_MAX_RECOVERY_RATE | \
 188				 CTR_FLAG_STRIPE_CACHE | \
 189				 CTR_FLAG_REGION_SIZE | \
 190				 CTR_FLAG_DELTA_DISKS | \
 191				 CTR_FLAG_DATA_OFFSET | \
 192				 CTR_FLAG_JOURNAL_DEV | \
 193				 CTR_FLAG_JOURNAL_MODE)
 194/* ...valid options definitions per raid level */
 195
 196/*
 197 * Flags for rs->runtime_flags field
 198 * (RT_FLAG prefix meaning "runtime flag")
 199 *
 200 * These are all internal and used to define runtime state,
 201 * e.g. to prevent another resume from preresume processing
 202 * the raid set all over again.
 203 */
 204#define RT_FLAG_RS_PRERESUMED		0
 205#define RT_FLAG_RS_RESUMED		1
 206#define RT_FLAG_RS_BITMAP_LOADED	2
 207#define RT_FLAG_UPDATE_SBS		3
 208#define RT_FLAG_RESHAPE_RS		4
 209#define RT_FLAG_RS_SUSPENDED		5
 210#define RT_FLAG_RS_IN_SYNC		6
 211#define RT_FLAG_RS_RESYNCING		7
 
 
 212
 213/* Array elements of 64 bit needed for rebuild/failed disk bits */
 214#define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
 215
 216/*
 217 * raid set level, layout and chunk sectors backup/restore
 218 */
 219struct rs_layout {
 220	int new_level;
 221	int new_layout;
 222	int new_chunk_sectors;
 223};
 224
 225struct raid_set {
 226	struct dm_target *ti;
 227
 228	uint32_t stripe_cache_entries;
 229	unsigned long ctr_flags;
 230	unsigned long runtime_flags;
 231
 232	uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
 233
 234	int raid_disks;
 235	int delta_disks;
 236	int data_offset;
 237	int raid10_copies;
 238	int requested_bitmap_chunk_sectors;
 239
 240	struct mddev md;
 241	struct raid_type *raid_type;
 242	struct dm_target_callbacks callbacks;
 
 
 243
 244	/* Optional raid4/5/6 journal device */
 245	struct journal_dev {
 246		struct dm_dev *dev;
 247		struct md_rdev rdev;
 248		int mode;
 249	} journal_dev;
 250
 251	struct raid_dev dev[0];
 252};
 253
 254static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)
 255{
 256	struct mddev *mddev = &rs->md;
 257
 258	l->new_level = mddev->new_level;
 259	l->new_layout = mddev->new_layout;
 260	l->new_chunk_sectors = mddev->new_chunk_sectors;
 261}
 262
 263static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)
 264{
 265	struct mddev *mddev = &rs->md;
 266
 267	mddev->new_level = l->new_level;
 268	mddev->new_layout = l->new_layout;
 269	mddev->new_chunk_sectors = l->new_chunk_sectors;
 270}
 271
 272/* raid10 algorithms (i.e. formats) */
 273#define	ALGORITHM_RAID10_DEFAULT	0
 274#define	ALGORITHM_RAID10_NEAR		1
 275#define	ALGORITHM_RAID10_OFFSET		2
 276#define	ALGORITHM_RAID10_FAR		3
 277
 278/* Supported raid types and properties. */
 279static struct raid_type {
 280	const char *name;		/* RAID algorithm. */
 281	const char *descr;		/* Descriptor text for logging. */
 282	const unsigned int parity_devs;	/* # of parity devices. */
 283	const unsigned int minimal_devs;/* minimal # of devices in set. */
 284	const unsigned int level;	/* RAID level. */
 285	const unsigned int algorithm;	/* RAID algorithm. */
 286} raid_types[] = {
 287	{"raid0",	  "raid0 (striping)",			    0, 2, 0,  0 /* NONE */},
 288	{"raid1",	  "raid1 (mirroring)",			    0, 2, 1,  0 /* NONE */},
 289	{"raid10_far",	  "raid10 far (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_FAR},
 290	{"raid10_offset", "raid10 offset (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_OFFSET},
 291	{"raid10_near",	  "raid10 near (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_NEAR},
 292	{"raid10",	  "raid10 (striped mirrors)",		    0, 2, 10, ALGORITHM_RAID10_DEFAULT},
 293	{"raid4",	  "raid4 (dedicated first parity disk)",    1, 2, 5,  ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */
 294	{"raid5_n",	  "raid5 (dedicated last parity disk)",	    1, 2, 5,  ALGORITHM_PARITY_N},
 295	{"raid5_ls",	  "raid5 (left symmetric)",		    1, 2, 5,  ALGORITHM_LEFT_SYMMETRIC},
 296	{"raid5_rs",	  "raid5 (right symmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_SYMMETRIC},
 297	{"raid5_la",	  "raid5 (left asymmetric)",		    1, 2, 5,  ALGORITHM_LEFT_ASYMMETRIC},
 298	{"raid5_ra",	  "raid5 (right asymmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_ASYMMETRIC},
 299	{"raid6_zr",	  "raid6 (zero restart)",		    2, 4, 6,  ALGORITHM_ROTATING_ZERO_RESTART},
 300	{"raid6_nr",	  "raid6 (N restart)",			    2, 4, 6,  ALGORITHM_ROTATING_N_RESTART},
 301	{"raid6_nc",	  "raid6 (N continue)",			    2, 4, 6,  ALGORITHM_ROTATING_N_CONTINUE},
 302	{"raid6_n_6",	  "raid6 (dedicated parity/Q n/6)",	    2, 4, 6,  ALGORITHM_PARITY_N_6},
 303	{"raid6_ls_6",	  "raid6 (left symmetric dedicated Q 6)",   2, 4, 6,  ALGORITHM_LEFT_SYMMETRIC_6},
 304	{"raid6_rs_6",	  "raid6 (right symmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_RIGHT_SYMMETRIC_6},
 305	{"raid6_la_6",	  "raid6 (left asymmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_LEFT_ASYMMETRIC_6},
 306	{"raid6_ra_6",	  "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6,  ALGORITHM_RIGHT_ASYMMETRIC_6}
 307};
 308
 309/* True, if @v is in inclusive range [@min, @max] */
 310static bool __within_range(long v, long min, long max)
 311{
 312	return v >= min && v <= max;
 313}
 314
 315/* All table line arguments are defined here */
 316static struct arg_name_flag {
 317	const unsigned long flag;
 318	const char *name;
 319} __arg_name_flags[] = {
 320	{ CTR_FLAG_SYNC, "sync"},
 321	{ CTR_FLAG_NOSYNC, "nosync"},
 322	{ CTR_FLAG_REBUILD, "rebuild"},
 323	{ CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
 324	{ CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
 325	{ CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
 326	{ CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
 327	{ CTR_FLAG_WRITE_MOSTLY, "write_mostly"},
 328	{ CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
 329	{ CTR_FLAG_REGION_SIZE, "region_size"},
 330	{ CTR_FLAG_RAID10_COPIES, "raid10_copies"},
 331	{ CTR_FLAG_RAID10_FORMAT, "raid10_format"},
 332	{ CTR_FLAG_DATA_OFFSET, "data_offset"},
 333	{ CTR_FLAG_DELTA_DISKS, "delta_disks"},
 334	{ CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
 335	{ CTR_FLAG_JOURNAL_DEV, "journal_dev" },
 336	{ CTR_FLAG_JOURNAL_MODE, "journal_mode" },
 337};
 338
 339/* Return argument name string for given @flag */
 340static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
 341{
 342	if (hweight32(flag) == 1) {
 343		struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
 344
 345		while (anf-- > __arg_name_flags)
 346			if (flag & anf->flag)
 347				return anf->name;
 348
 349	} else
 350		DMERR("%s called with more than one flag!", __func__);
 351
 352	return NULL;
 353}
 354
 355/* Define correlation of raid456 journal cache modes and dm-raid target line parameters */
 356static struct {
 357	const int mode;
 358	const char *param;
 359} _raid456_journal_mode[] = {
 360	{ R5C_JOURNAL_MODE_WRITE_THROUGH , "writethrough" },
 361	{ R5C_JOURNAL_MODE_WRITE_BACK    , "writeback" }
 362};
 363
 364/* Return MD raid4/5/6 journal mode for dm @journal_mode one */
 365static int dm_raid_journal_mode_to_md(const char *mode)
 366{
 367	int m = ARRAY_SIZE(_raid456_journal_mode);
 368
 369	while (m--)
 370		if (!strcasecmp(mode, _raid456_journal_mode[m].param))
 371			return _raid456_journal_mode[m].mode;
 372
 373	return -EINVAL;
 374}
 375
 376/* Return dm-raid raid4/5/6 journal mode string for @mode */
 377static const char *md_journal_mode_to_dm_raid(const int mode)
 378{
 379	int m = ARRAY_SIZE(_raid456_journal_mode);
 380
 381	while (m--)
 382		if (mode == _raid456_journal_mode[m].mode)
 383			return _raid456_journal_mode[m].param;
 384
 385	return "unknown";
 386}
 387
 388/*
 389 * Bool helpers to test for various raid levels of a raid set.
 390 * It's level as reported by the superblock rather than
 391 * the requested raid_type passed to the constructor.
 392 */
 393/* Return true, if raid set in @rs is raid0 */
 394static bool rs_is_raid0(struct raid_set *rs)
 395{
 396	return !rs->md.level;
 397}
 398
 399/* Return true, if raid set in @rs is raid1 */
 400static bool rs_is_raid1(struct raid_set *rs)
 401{
 402	return rs->md.level == 1;
 403}
 404
 405/* Return true, if raid set in @rs is raid10 */
 406static bool rs_is_raid10(struct raid_set *rs)
 407{
 408	return rs->md.level == 10;
 409}
 410
 411/* Return true, if raid set in @rs is level 6 */
 412static bool rs_is_raid6(struct raid_set *rs)
 413{
 414	return rs->md.level == 6;
 415}
 416
 417/* Return true, if raid set in @rs is level 4, 5 or 6 */
 418static bool rs_is_raid456(struct raid_set *rs)
 419{
 420	return __within_range(rs->md.level, 4, 6);
 421}
 422
 423/* Return true, if raid set in @rs is reshapable */
 424static bool __is_raid10_far(int layout);
 425static bool rs_is_reshapable(struct raid_set *rs)
 426{
 427	return rs_is_raid456(rs) ||
 428	       (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
 429}
 430
 431/* Return true, if raid set in @rs is recovering */
 432static bool rs_is_recovering(struct raid_set *rs)
 433{
 434	return rs->md.recovery_cp < rs->md.dev_sectors;
 435}
 436
 437/* Return true, if raid set in @rs is reshaping */
 438static bool rs_is_reshaping(struct raid_set *rs)
 439{
 440	return rs->md.reshape_position != MaxSector;
 441}
 442
 443/*
 444 * bool helpers to test for various raid levels of a raid type @rt
 445 */
 446
 447/* Return true, if raid type in @rt is raid0 */
 448static bool rt_is_raid0(struct raid_type *rt)
 449{
 450	return !rt->level;
 451}
 452
 453/* Return true, if raid type in @rt is raid1 */
 454static bool rt_is_raid1(struct raid_type *rt)
 455{
 456	return rt->level == 1;
 457}
 458
 459/* Return true, if raid type in @rt is raid10 */
 460static bool rt_is_raid10(struct raid_type *rt)
 461{
 462	return rt->level == 10;
 463}
 464
 465/* Return true, if raid type in @rt is raid4/5 */
 466static bool rt_is_raid45(struct raid_type *rt)
 467{
 468	return __within_range(rt->level, 4, 5);
 469}
 470
 471/* Return true, if raid type in @rt is raid6 */
 472static bool rt_is_raid6(struct raid_type *rt)
 473{
 474	return rt->level == 6;
 475}
 476
 477/* Return true, if raid type in @rt is raid4/5/6 */
 478static bool rt_is_raid456(struct raid_type *rt)
 479{
 480	return __within_range(rt->level, 4, 6);
 481}
 482/* END: raid level bools */
 483
 484/* Return valid ctr flags for the raid level of @rs */
 485static unsigned long __valid_flags(struct raid_set *rs)
 486{
 487	if (rt_is_raid0(rs->raid_type))
 488		return RAID0_VALID_FLAGS;
 489	else if (rt_is_raid1(rs->raid_type))
 490		return RAID1_VALID_FLAGS;
 491	else if (rt_is_raid10(rs->raid_type))
 492		return RAID10_VALID_FLAGS;
 493	else if (rt_is_raid45(rs->raid_type))
 494		return RAID45_VALID_FLAGS;
 495	else if (rt_is_raid6(rs->raid_type))
 496		return RAID6_VALID_FLAGS;
 497
 498	return 0;
 499}
 500
 501/*
 502 * Check for valid flags set on @rs
 503 *
 504 * Has to be called after parsing of the ctr flags!
 505 */
 506static int rs_check_for_valid_flags(struct raid_set *rs)
 507{
 508	if (rs->ctr_flags & ~__valid_flags(rs)) {
 509		rs->ti->error = "Invalid flags combination";
 510		return -EINVAL;
 511	}
 512
 513	return 0;
 514}
 515
 516/* MD raid10 bit definitions and helpers */
 517#define RAID10_OFFSET			(1 << 16) /* stripes with data copies area adjacent on devices */
 518#define RAID10_BROCKEN_USE_FAR_SETS	(1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
 519#define RAID10_USE_FAR_SETS		(1 << 18) /* Use sets instead of whole stripe rotation */
 520#define RAID10_FAR_COPIES_SHIFT		8	  /* raid10 # far copies shift (2nd byte of layout) */
 521
 522/* Return md raid10 near copies for @layout */
 523static unsigned int __raid10_near_copies(int layout)
 524{
 525	return layout & 0xFF;
 526}
 527
 528/* Return md raid10 far copies for @layout */
 529static unsigned int __raid10_far_copies(int layout)
 530{
 531	return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
 532}
 533
 534/* Return true if md raid10 offset for @layout */
 535static bool __is_raid10_offset(int layout)
 536{
 537	return !!(layout & RAID10_OFFSET);
 538}
 539
 540/* Return true if md raid10 near for @layout */
 541static bool __is_raid10_near(int layout)
 542{
 543	return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
 544}
 545
 546/* Return true if md raid10 far for @layout */
 547static bool __is_raid10_far(int layout)
 548{
 549	return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
 550}
 551
 552/* Return md raid10 layout string for @layout */
 553static const char *raid10_md_layout_to_format(int layout)
 554{
 555	/*
 556	 * Bit 16 stands for "offset"
 557	 * (i.e. adjacent stripes hold copies)
 558	 *
 559	 * Refer to MD's raid10.c for details
 560	 */
 561	if (__is_raid10_offset(layout))
 562		return "offset";
 563
 564	if (__raid10_near_copies(layout) > 1)
 565		return "near";
 566
 567	if (__raid10_far_copies(layout) > 1)
 568		return "far";
 569
 570	return "unknown";
 571}
 572
 573/* Return md raid10 algorithm for @name */
 574static int raid10_name_to_format(const char *name)
 575{
 576	if (!strcasecmp(name, "near"))
 577		return ALGORITHM_RAID10_NEAR;
 578	else if (!strcasecmp(name, "offset"))
 579		return ALGORITHM_RAID10_OFFSET;
 580	else if (!strcasecmp(name, "far"))
 581		return ALGORITHM_RAID10_FAR;
 582
 583	return -EINVAL;
 584}
 585
 586/* Return md raid10 copies for @layout */
 587static unsigned int raid10_md_layout_to_copies(int layout)
 588{
 589	return max(__raid10_near_copies(layout), __raid10_far_copies(layout));
 590}
 591
 592/* Return md raid10 format id for @format string */
 593static int raid10_format_to_md_layout(struct raid_set *rs,
 594				      unsigned int algorithm,
 595				      unsigned int copies)
 596{
 597	unsigned int n = 1, f = 1, r = 0;
 598
 599	/*
 600	 * MD resilienece flaw:
 601	 *
 602	 * enabling use_far_sets for far/offset formats causes copies
 603	 * to be colocated on the same devs together with their origins!
 604	 *
 605	 * -> disable it for now in the definition above
 606	 */
 607	if (algorithm == ALGORITHM_RAID10_DEFAULT ||
 608	    algorithm == ALGORITHM_RAID10_NEAR)
 609		n = copies;
 610
 611	else if (algorithm == ALGORITHM_RAID10_OFFSET) {
 612		f = copies;
 613		r = RAID10_OFFSET;
 614		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 615			r |= RAID10_USE_FAR_SETS;
 616
 617	} else if (algorithm == ALGORITHM_RAID10_FAR) {
 618		f = copies;
 619		r = !RAID10_OFFSET;
 620		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 621			r |= RAID10_USE_FAR_SETS;
 622
 623	} else
 624		return -EINVAL;
 625
 626	return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
 627}
 628/* END: MD raid10 bit definitions and helpers */
 629
 630/* Check for any of the raid10 algorithms */
 631static bool __got_raid10(struct raid_type *rtp, const int layout)
 632{
 633	if (rtp->level == 10) {
 634		switch (rtp->algorithm) {
 635		case ALGORITHM_RAID10_DEFAULT:
 636		case ALGORITHM_RAID10_NEAR:
 637			return __is_raid10_near(layout);
 638		case ALGORITHM_RAID10_OFFSET:
 639			return __is_raid10_offset(layout);
 640		case ALGORITHM_RAID10_FAR:
 641			return __is_raid10_far(layout);
 642		default:
 643			break;
 644		}
 645	}
 646
 647	return false;
 648}
 649
 650/* Return raid_type for @name */
 651static struct raid_type *get_raid_type(const char *name)
 652{
 653	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 654
 655	while (rtp-- > raid_types)
 656		if (!strcasecmp(rtp->name, name))
 657			return rtp;
 658
 659	return NULL;
 660}
 661
 662/* Return raid_type for @name based derived from @level and @layout */
 663static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
 664{
 665	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 666
 667	while (rtp-- > raid_types) {
 668		/* RAID10 special checks based on @layout flags/properties */
 669		if (rtp->level == level &&
 670		    (__got_raid10(rtp, layout) || rtp->algorithm == layout))
 671			return rtp;
 672	}
 673
 674	return NULL;
 675}
 676
 677/* Adjust rdev sectors */
 678static void rs_set_rdev_sectors(struct raid_set *rs)
 679{
 680	struct mddev *mddev = &rs->md;
 681	struct md_rdev *rdev;
 682
 683	/*
 684	 * raid10 sets rdev->sector to the device size, which
 685	 * is unintended in case of out-of-place reshaping
 686	 */
 687	rdev_for_each(rdev, mddev)
 688		if (!test_bit(Journal, &rdev->flags))
 689			rdev->sectors = mddev->dev_sectors;
 690}
 691
 692/*
 693 * Change bdev capacity of @rs in case of a disk add/remove reshape
 694 */
 695static void rs_set_capacity(struct raid_set *rs)
 696{
 697	struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
 698
 699	set_capacity(gendisk, rs->md.array_sectors);
 700	revalidate_disk(gendisk);
 701}
 702
 703/*
 704 * Set the mddev properties in @rs to the current
 705 * ones retrieved from the freshest superblock
 706 */
 707static void rs_set_cur(struct raid_set *rs)
 708{
 709	struct mddev *mddev = &rs->md;
 710
 711	mddev->new_level = mddev->level;
 712	mddev->new_layout = mddev->layout;
 713	mddev->new_chunk_sectors = mddev->chunk_sectors;
 714}
 715
 716/*
 717 * Set the mddev properties in @rs to the new
 718 * ones requested by the ctr
 719 */
 720static void rs_set_new(struct raid_set *rs)
 721{
 722	struct mddev *mddev = &rs->md;
 723
 724	mddev->level = mddev->new_level;
 725	mddev->layout = mddev->new_layout;
 726	mddev->chunk_sectors = mddev->new_chunk_sectors;
 727	mddev->raid_disks = rs->raid_disks;
 728	mddev->delta_disks = 0;
 729}
 730
 731static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
 732				       unsigned int raid_devs)
 733{
 734	unsigned int i;
 735	struct raid_set *rs;
 736
 737	if (raid_devs <= raid_type->parity_devs) {
 738		ti->error = "Insufficient number of devices";
 739		return ERR_PTR(-EINVAL);
 740	}
 741
 742	rs = kzalloc(struct_size(rs, dev, raid_devs), GFP_KERNEL);
 743	if (!rs) {
 744		ti->error = "Cannot allocate raid context";
 745		return ERR_PTR(-ENOMEM);
 746	}
 747
 748	mddev_init(&rs->md);
 
 
 
 
 749
 750	rs->raid_disks = raid_devs;
 751	rs->delta_disks = 0;
 752
 753	rs->ti = ti;
 754	rs->raid_type = raid_type;
 755	rs->stripe_cache_entries = 256;
 756	rs->md.raid_disks = raid_devs;
 757	rs->md.level = raid_type->level;
 758	rs->md.new_level = rs->md.level;
 759	rs->md.layout = raid_type->algorithm;
 760	rs->md.new_layout = rs->md.layout;
 761	rs->md.delta_disks = 0;
 762	rs->md.recovery_cp = MaxSector;
 763
 764	for (i = 0; i < raid_devs; i++)
 765		md_rdev_init(&rs->dev[i].rdev);
 766
 767	/*
 768	 * Remaining items to be initialized by further RAID params:
 769	 *  rs->md.persistent
 770	 *  rs->md.external
 771	 *  rs->md.chunk_sectors
 772	 *  rs->md.new_chunk_sectors
 773	 *  rs->md.dev_sectors
 774	 */
 775
 776	return rs;
 777}
 778
 779/* Free all @rs allocations */
 780static void raid_set_free(struct raid_set *rs)
 781{
 782	int i;
 783
 784	if (rs->journal_dev.dev) {
 785		md_rdev_clear(&rs->journal_dev.rdev);
 786		dm_put_device(rs->ti, rs->journal_dev.dev);
 787	}
 788
 789	for (i = 0; i < rs->raid_disks; i++) {
 790		if (rs->dev[i].meta_dev)
 791			dm_put_device(rs->ti, rs->dev[i].meta_dev);
 792		md_rdev_clear(&rs->dev[i].rdev);
 793		if (rs->dev[i].data_dev)
 794			dm_put_device(rs->ti, rs->dev[i].data_dev);
 795	}
 796
 
 797	kfree(rs);
 798}
 799
 800/*
 801 * For every device we have two words
 802 *  <meta_dev>: meta device name or '-' if missing
 803 *  <data_dev>: data device name or '-' if missing
 804 *
 805 * The following are permitted:
 806 *    - -
 807 *    - <data_dev>
 808 *    <meta_dev> <data_dev>
 809 *
 810 * The following is not allowed:
 811 *    <meta_dev> -
 812 *
 813 * This code parses those words.  If there is a failure,
 814 * the caller must use raid_set_free() to unwind the operations.
 815 */
 816static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
 817{
 818	int i;
 819	int rebuild = 0;
 820	int metadata_available = 0;
 821	int r = 0;
 822	const char *arg;
 823
 824	/* Put off the number of raid devices argument to get to dev pairs */
 825	arg = dm_shift_arg(as);
 826	if (!arg)
 827		return -EINVAL;
 828
 829	for (i = 0; i < rs->raid_disks; i++) {
 830		rs->dev[i].rdev.raid_disk = i;
 831
 832		rs->dev[i].meta_dev = NULL;
 833		rs->dev[i].data_dev = NULL;
 834
 835		/*
 836		 * There are no offsets initially.
 837		 * Out of place reshape will set them accordingly.
 838		 */
 839		rs->dev[i].rdev.data_offset = 0;
 840		rs->dev[i].rdev.new_data_offset = 0;
 841		rs->dev[i].rdev.mddev = &rs->md;
 842
 843		arg = dm_shift_arg(as);
 844		if (!arg)
 845			return -EINVAL;
 846
 847		if (strcmp(arg, "-")) {
 848			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 849					  &rs->dev[i].meta_dev);
 850			if (r) {
 851				rs->ti->error = "RAID metadata device lookup failure";
 852				return r;
 853			}
 854
 855			rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
 856			if (!rs->dev[i].rdev.sb_page) {
 857				rs->ti->error = "Failed to allocate superblock page";
 858				return -ENOMEM;
 859			}
 860		}
 861
 862		arg = dm_shift_arg(as);
 863		if (!arg)
 864			return -EINVAL;
 865
 866		if (!strcmp(arg, "-")) {
 867			if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
 868			    (!rs->dev[i].rdev.recovery_offset)) {
 869				rs->ti->error = "Drive designated for rebuild not specified";
 870				return -EINVAL;
 871			}
 872
 873			if (rs->dev[i].meta_dev) {
 874				rs->ti->error = "No data device supplied with metadata device";
 875				return -EINVAL;
 876			}
 877
 878			continue;
 879		}
 880
 881		r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 882				  &rs->dev[i].data_dev);
 883		if (r) {
 884			rs->ti->error = "RAID device lookup failure";
 885			return r;
 886		}
 887
 888		if (rs->dev[i].meta_dev) {
 889			metadata_available = 1;
 890			rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
 891		}
 892		rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
 893		list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
 894		if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
 895			rebuild++;
 896	}
 897
 898	if (rs->journal_dev.dev)
 899		list_add_tail(&rs->journal_dev.rdev.same_set, &rs->md.disks);
 900
 901	if (metadata_available) {
 902		rs->md.external = 0;
 903		rs->md.persistent = 1;
 904		rs->md.major_version = 2;
 905	} else if (rebuild && !rs->md.recovery_cp) {
 906		/*
 907		 * Without metadata, we will not be able to tell if the array
 908		 * is in-sync or not - we must assume it is not.  Therefore,
 909		 * it is impossible to rebuild a drive.
 910		 *
 911		 * Even if there is metadata, the on-disk information may
 912		 * indicate that the array is not in-sync and it will then
 913		 * fail at that time.
 914		 *
 915		 * User could specify 'nosync' option if desperate.
 916		 */
 917		rs->ti->error = "Unable to rebuild drive while array is not in-sync";
 918		return -EINVAL;
 919	}
 920
 921	return 0;
 922}
 923
 924/*
 925 * validate_region_size
 926 * @rs
 927 * @region_size:  region size in sectors.  If 0, pick a size (4MiB default).
 928 *
 929 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
 930 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
 931 *
 932 * Returns: 0 on success, -EINVAL on failure.
 933 */
 934static int validate_region_size(struct raid_set *rs, unsigned long region_size)
 935{
 936	unsigned long min_region_size = rs->ti->len / (1 << 21);
 937
 938	if (rs_is_raid0(rs))
 939		return 0;
 940
 941	if (!region_size) {
 942		/*
 943		 * Choose a reasonable default.	 All figures in sectors.
 944		 */
 945		if (min_region_size > (1 << 13)) {
 946			/* If not a power of 2, make it the next power of 2 */
 947			region_size = roundup_pow_of_two(min_region_size);
 948			DMINFO("Choosing default region size of %lu sectors",
 949			       region_size);
 950		} else {
 951			DMINFO("Choosing default region size of 4MiB");
 952			region_size = 1 << 13; /* sectors */
 953		}
 954	} else {
 955		/*
 956		 * Validate user-supplied value.
 957		 */
 958		if (region_size > rs->ti->len) {
 959			rs->ti->error = "Supplied region size is too large";
 960			return -EINVAL;
 961		}
 962
 963		if (region_size < min_region_size) {
 964			DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
 965			      region_size, min_region_size);
 966			rs->ti->error = "Supplied region size is too small";
 967			return -EINVAL;
 968		}
 969
 970		if (!is_power_of_2(region_size)) {
 971			rs->ti->error = "Region size is not a power of 2";
 972			return -EINVAL;
 973		}
 974
 975		if (region_size < rs->md.chunk_sectors) {
 976			rs->ti->error = "Region size is smaller than the chunk size";
 977			return -EINVAL;
 978		}
 979	}
 980
 981	/*
 982	 * Convert sectors to bytes.
 983	 */
 984	rs->md.bitmap_info.chunksize = to_bytes(region_size);
 985
 986	return 0;
 987}
 988
 989/*
 990 * validate_raid_redundancy
 991 * @rs
 992 *
 993 * Determine if there are enough devices in the array that haven't
 994 * failed (or are being rebuilt) to form a usable array.
 995 *
 996 * Returns: 0 on success, -EINVAL on failure.
 997 */
 998static int validate_raid_redundancy(struct raid_set *rs)
 999{
1000	unsigned int i, rebuild_cnt = 0;
1001	unsigned int rebuilds_per_group = 0, copies;
1002	unsigned int group_size, last_group_start;
1003
1004	for (i = 0; i < rs->md.raid_disks; i++)
1005		if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
1006		    !rs->dev[i].rdev.sb_page)
 
1007			rebuild_cnt++;
1008
1009	switch (rs->md.level) {
1010	case 0:
1011		break;
1012	case 1:
1013		if (rebuild_cnt >= rs->md.raid_disks)
1014			goto too_many;
1015		break;
1016	case 4:
1017	case 5:
1018	case 6:
1019		if (rebuild_cnt > rs->raid_type->parity_devs)
1020			goto too_many;
1021		break;
1022	case 10:
1023		copies = raid10_md_layout_to_copies(rs->md.new_layout);
1024		if (copies < 2) {
1025			DMERR("Bogus raid10 data copies < 2!");
1026			return -EINVAL;
1027		}
1028
1029		if (rebuild_cnt < copies)
1030			break;
1031
1032		/*
1033		 * It is possible to have a higher rebuild count for RAID10,
1034		 * as long as the failed devices occur in different mirror
1035		 * groups (i.e. different stripes).
1036		 *
1037		 * When checking "near" format, make sure no adjacent devices
1038		 * have failed beyond what can be handled.  In addition to the
1039		 * simple case where the number of devices is a multiple of the
1040		 * number of copies, we must also handle cases where the number
1041		 * of devices is not a multiple of the number of copies.
1042		 * E.g.	   dev1 dev2 dev3 dev4 dev5
1043		 *	    A	 A    B	   B	C
1044		 *	    C	 D    D	   E	E
1045		 */
 
1046		if (__is_raid10_near(rs->md.new_layout)) {
1047			for (i = 0; i < rs->md.raid_disks; i++) {
1048				if (!(i % copies))
1049					rebuilds_per_group = 0;
1050				if ((!rs->dev[i].rdev.sb_page ||
1051				    !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1052				    (++rebuilds_per_group >= copies))
1053					goto too_many;
1054			}
1055			break;
1056		}
1057
1058		/*
1059		 * When checking "far" and "offset" formats, we need to ensure
1060		 * that the device that holds its copy is not also dead or
1061		 * being rebuilt.  (Note that "far" and "offset" formats only
1062		 * support two copies right now.  These formats also only ever
1063		 * use the 'use_far_sets' variant.)
1064		 *
1065		 * This check is somewhat complicated by the need to account
1066		 * for arrays that are not a multiple of (far) copies.	This
1067		 * results in the need to treat the last (potentially larger)
1068		 * set differently.
1069		 */
1070		group_size = (rs->md.raid_disks / copies);
1071		last_group_start = (rs->md.raid_disks / group_size) - 1;
1072		last_group_start *= group_size;
1073		for (i = 0; i < rs->md.raid_disks; i++) {
1074			if (!(i % copies) && !(i > last_group_start))
1075				rebuilds_per_group = 0;
1076			if ((!rs->dev[i].rdev.sb_page ||
1077			     !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1078			    (++rebuilds_per_group >= copies))
1079					goto too_many;
1080		}
1081		break;
1082	default:
1083		if (rebuild_cnt)
1084			return -EINVAL;
1085	}
1086
1087	return 0;
1088
1089too_many:
1090	return -EINVAL;
1091}
1092
1093/*
1094 * Possible arguments are...
1095 *	<chunk_size> [optional_args]
1096 *
1097 * Argument definitions
1098 *    <chunk_size>			The number of sectors per disk that
1099 *					will form the "stripe"
1100 *    [[no]sync]			Force or prevent recovery of the
1101 *					entire array
1102 *    [rebuild <idx>]			Rebuild the drive indicated by the index
1103 *    [daemon_sleep <ms>]		Time between bitmap daemon work to
1104 *					clear bits
1105 *    [min_recovery_rate <kB/sec/disk>]	Throttle RAID initialization
1106 *    [max_recovery_rate <kB/sec/disk>]	Throttle RAID initialization
1107 *    [write_mostly <idx>]		Indicate a write mostly drive via index
1108 *    [max_write_behind <sectors>]	See '-write-behind=' (man mdadm)
1109 *    [stripe_cache <sectors>]		Stripe cache size for higher RAIDs
1110 *    [region_size <sectors>]		Defines granularity of bitmap
1111 *    [journal_dev <dev>]		raid4/5/6 journaling deviice
1112 *    					(i.e. write hole closing log)
1113 *
1114 * RAID10-only options:
1115 *    [raid10_copies <# copies>]	Number of copies.  (Default: 2)
1116 *    [raid10_format <near|far|offset>] Layout algorithm.  (Default: near)
1117 */
1118static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
1119			     unsigned int num_raid_params)
1120{
1121	int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
1122	unsigned int raid10_copies = 2;
1123	unsigned int i, write_mostly = 0;
1124	unsigned int region_size = 0;
1125	sector_t max_io_len;
1126	const char *arg, *key;
1127	struct raid_dev *rd;
1128	struct raid_type *rt = rs->raid_type;
1129
1130	arg = dm_shift_arg(as);
1131	num_raid_params--; /* Account for chunk_size argument */
1132
1133	if (kstrtoint(arg, 10, &value) < 0) {
1134		rs->ti->error = "Bad numerical argument given for chunk_size";
1135		return -EINVAL;
1136	}
1137
1138	/*
1139	 * First, parse the in-order required arguments
1140	 * "chunk_size" is the only argument of this type.
1141	 */
1142	if (rt_is_raid1(rt)) {
1143		if (value)
1144			DMERR("Ignoring chunk size parameter for RAID 1");
1145		value = 0;
1146	} else if (!is_power_of_2(value)) {
1147		rs->ti->error = "Chunk size must be a power of 2";
1148		return -EINVAL;
1149	} else if (value < 8) {
1150		rs->ti->error = "Chunk size value is too small";
1151		return -EINVAL;
1152	}
1153
1154	rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1155
1156	/*
1157	 * We set each individual device as In_sync with a completed
1158	 * 'recovery_offset'.  If there has been a device failure or
1159	 * replacement then one of the following cases applies:
1160	 *
1161	 *   1) User specifies 'rebuild'.
1162	 *	- Device is reset when param is read.
1163	 *   2) A new device is supplied.
1164	 *	- No matching superblock found, resets device.
1165	 *   3) Device failure was transient and returns on reload.
1166	 *	- Failure noticed, resets device for bitmap replay.
1167	 *   4) Device hadn't completed recovery after previous failure.
1168	 *	- Superblock is read and overrides recovery_offset.
1169	 *
1170	 * What is found in the superblocks of the devices is always
1171	 * authoritative, unless 'rebuild' or '[no]sync' was specified.
1172	 */
1173	for (i = 0; i < rs->raid_disks; i++) {
1174		set_bit(In_sync, &rs->dev[i].rdev.flags);
1175		rs->dev[i].rdev.recovery_offset = MaxSector;
1176	}
1177
1178	/*
1179	 * Second, parse the unordered optional arguments
1180	 */
1181	for (i = 0; i < num_raid_params; i++) {
1182		key = dm_shift_arg(as);
1183		if (!key) {
1184			rs->ti->error = "Not enough raid parameters given";
1185			return -EINVAL;
1186		}
1187
1188		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1189			if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1190				rs->ti->error = "Only one 'nosync' argument allowed";
1191				return -EINVAL;
1192			}
1193			continue;
1194		}
1195		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1196			if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1197				rs->ti->error = "Only one 'sync' argument allowed";
1198				return -EINVAL;
1199			}
1200			continue;
1201		}
1202		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1203			if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1204				rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1205				return -EINVAL;
1206			}
1207			continue;
1208		}
1209
1210		arg = dm_shift_arg(as);
1211		i++; /* Account for the argument pairs */
1212		if (!arg) {
1213			rs->ti->error = "Wrong number of raid parameters given";
1214			return -EINVAL;
1215		}
1216
1217		/*
1218		 * Parameters that take a string value are checked here.
1219		 */
1220		/* "raid10_format {near|offset|far} */
1221		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1222			if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1223				rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1224				return -EINVAL;
1225			}
1226			if (!rt_is_raid10(rt)) {
1227				rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1228				return -EINVAL;
1229			}
1230			raid10_format = raid10_name_to_format(arg);
1231			if (raid10_format < 0) {
1232				rs->ti->error = "Invalid 'raid10_format' value given";
1233				return raid10_format;
1234			}
1235			continue;
1236		}
1237
1238		/* "journal_dev <dev>" */
1239		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV))) {
1240			int r;
1241			struct md_rdev *jdev;
1242
1243			if (test_and_set_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
1244				rs->ti->error = "Only one raid4/5/6 set journaling device allowed";
1245				return -EINVAL;
1246			}
1247			if (!rt_is_raid456(rt)) {
1248				rs->ti->error = "'journal_dev' is an invalid parameter for this RAID type";
1249				return -EINVAL;
1250			}
1251			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
1252					  &rs->journal_dev.dev);
1253			if (r) {
1254				rs->ti->error = "raid4/5/6 journal device lookup failure";
1255				return r;
1256			}
1257			jdev = &rs->journal_dev.rdev;
1258			md_rdev_init(jdev);
1259			jdev->mddev = &rs->md;
1260			jdev->bdev = rs->journal_dev.dev->bdev;
1261			jdev->sectors = to_sector(i_size_read(jdev->bdev->bd_inode));
1262			if (jdev->sectors < MIN_RAID456_JOURNAL_SPACE) {
1263				rs->ti->error = "No space for raid4/5/6 journal";
1264				return -ENOSPC;
1265			}
1266			rs->journal_dev.mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
1267			set_bit(Journal, &jdev->flags);
1268			continue;
1269		}
1270
1271		/* "journal_mode <mode>" ("journal_dev" mandatory!) */
1272		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE))) {
1273			int r;
1274
1275			if (!test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
1276				rs->ti->error = "raid4/5/6 'journal_mode' is invalid without 'journal_dev'";
1277				return -EINVAL;
1278			}
1279			if (test_and_set_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
1280				rs->ti->error = "Only one raid4/5/6 'journal_mode' argument allowed";
1281				return -EINVAL;
1282			}
1283			r = dm_raid_journal_mode_to_md(arg);
1284			if (r < 0) {
1285				rs->ti->error = "Invalid 'journal_mode' argument";
1286				return r;
1287			}
1288			rs->journal_dev.mode = r;
1289			continue;
1290		}
1291
1292		/*
1293		 * Parameters with number values from here on.
1294		 */
1295		if (kstrtoint(arg, 10, &value) < 0) {
1296			rs->ti->error = "Bad numerical argument given in raid params";
1297			return -EINVAL;
1298		}
1299
1300		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1301			/*
1302			 * "rebuild" is being passed in by userspace to provide
1303			 * indexes of replaced devices and to set up additional
1304			 * devices on raid level takeover.
1305			 */
1306			if (!__within_range(value, 0, rs->raid_disks - 1)) {
1307				rs->ti->error = "Invalid rebuild index given";
1308				return -EINVAL;
1309			}
1310
1311			if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1312				rs->ti->error = "rebuild for this index already given";
1313				return -EINVAL;
1314			}
1315
1316			rd = rs->dev + value;
1317			clear_bit(In_sync, &rd->rdev.flags);
1318			clear_bit(Faulty, &rd->rdev.flags);
1319			rd->rdev.recovery_offset = 0;
1320			set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1321		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1322			if (!rt_is_raid1(rt)) {
1323				rs->ti->error = "write_mostly option is only valid for RAID1";
1324				return -EINVAL;
1325			}
1326
1327			if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1328				rs->ti->error = "Invalid write_mostly index given";
1329				return -EINVAL;
1330			}
1331
1332			write_mostly++;
1333			set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1334			set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1335		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1336			if (!rt_is_raid1(rt)) {
1337				rs->ti->error = "max_write_behind option is only valid for RAID1";
1338				return -EINVAL;
1339			}
1340
1341			if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1342				rs->ti->error = "Only one max_write_behind argument pair allowed";
1343				return -EINVAL;
1344			}
1345
1346			/*
1347			 * In device-mapper, we specify things in sectors, but
1348			 * MD records this value in kB
1349			 */
1350			if (value < 0 || value / 2 > COUNTER_MAX) {
1351				rs->ti->error = "Max write-behind limit out of range";
1352				return -EINVAL;
1353			}
1354
1355			rs->md.bitmap_info.max_write_behind = value / 2;
1356		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1357			if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1358				rs->ti->error = "Only one daemon_sleep argument pair allowed";
1359				return -EINVAL;
1360			}
1361			if (value < 0) {
1362				rs->ti->error = "daemon sleep period out of range";
1363				return -EINVAL;
1364			}
1365			rs->md.bitmap_info.daemon_sleep = value;
1366		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1367			/* Userspace passes new data_offset after having extended the the data image LV */
1368			if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1369				rs->ti->error = "Only one data_offset argument pair allowed";
1370				return -EINVAL;
1371			}
1372			/* Ensure sensible data offset */
1373			if (value < 0 ||
1374			    (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {
1375				rs->ti->error = "Bogus data_offset value";
1376				return -EINVAL;
1377			}
1378			rs->data_offset = value;
1379		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1380			/* Define the +/-# of disks to add to/remove from the given raid set */
1381			if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1382				rs->ti->error = "Only one delta_disks argument pair allowed";
1383				return -EINVAL;
1384			}
1385			/* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1386			if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1387				rs->ti->error = "Too many delta_disk requested";
1388				return -EINVAL;
1389			}
1390
1391			rs->delta_disks = value;
1392		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1393			if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1394				rs->ti->error = "Only one stripe_cache argument pair allowed";
1395				return -EINVAL;
1396			}
1397
1398			if (!rt_is_raid456(rt)) {
1399				rs->ti->error = "Inappropriate argument: stripe_cache";
1400				return -EINVAL;
1401			}
1402
1403			if (value < 0) {
1404				rs->ti->error = "Bogus stripe cache entries value";
1405				return -EINVAL;
1406			}
1407			rs->stripe_cache_entries = value;
1408		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1409			if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1410				rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1411				return -EINVAL;
1412			}
1413
1414			if (value < 0) {
1415				rs->ti->error = "min_recovery_rate out of range";
1416				return -EINVAL;
1417			}
1418			rs->md.sync_speed_min = value;
1419		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1420			if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
1421				rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1422				return -EINVAL;
1423			}
1424
1425			if (value < 0) {
1426				rs->ti->error = "max_recovery_rate out of range";
1427				return -EINVAL;
1428			}
1429			rs->md.sync_speed_max = value;
1430		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1431			if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1432				rs->ti->error = "Only one region_size argument pair allowed";
1433				return -EINVAL;
1434			}
1435
1436			region_size = value;
1437			rs->requested_bitmap_chunk_sectors = value;
1438		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1439			if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1440				rs->ti->error = "Only one raid10_copies argument pair allowed";
1441				return -EINVAL;
1442			}
1443
1444			if (!__within_range(value, 2, rs->md.raid_disks)) {
1445				rs->ti->error = "Bad value for 'raid10_copies'";
1446				return -EINVAL;
1447			}
1448
1449			raid10_copies = value;
1450		} else {
1451			DMERR("Unable to parse RAID parameter: %s", key);
1452			rs->ti->error = "Unable to parse RAID parameter";
1453			return -EINVAL;
1454		}
1455	}
1456
1457	if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1458	    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1459		rs->ti->error = "sync and nosync are mutually exclusive";
1460		return -EINVAL;
1461	}
1462
1463	if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
1464	    (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
1465	     test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
1466		rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
1467		return -EINVAL;
1468	}
1469
1470	if (write_mostly >= rs->md.raid_disks) {
1471		rs->ti->error = "Can't set all raid1 devices to write_mostly";
1472		return -EINVAL;
1473	}
1474
1475	if (rs->md.sync_speed_max &&
1476	    rs->md.sync_speed_min > rs->md.sync_speed_max) {
1477		rs->ti->error = "Bogus recovery rates";
1478		return -EINVAL;
1479	}
1480
1481	if (validate_region_size(rs, region_size))
1482		return -EINVAL;
1483
1484	if (rs->md.chunk_sectors)
1485		max_io_len = rs->md.chunk_sectors;
1486	else
1487		max_io_len = region_size;
1488
1489	if (dm_set_target_max_io_len(rs->ti, max_io_len))
1490		return -EINVAL;
1491
1492	if (rt_is_raid10(rt)) {
1493		if (raid10_copies > rs->md.raid_disks) {
1494			rs->ti->error = "Not enough devices to satisfy specification";
1495			return -EINVAL;
1496		}
1497
1498		rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1499		if (rs->md.new_layout < 0) {
1500			rs->ti->error = "Error getting raid10 format";
1501			return rs->md.new_layout;
1502		}
1503
1504		rt = get_raid_type_by_ll(10, rs->md.new_layout);
1505		if (!rt) {
1506			rs->ti->error = "Failed to recognize new raid10 layout";
1507			return -EINVAL;
1508		}
1509
1510		if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1511		     rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1512		    test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1513			rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1514			return -EINVAL;
1515		}
1516	}
1517
1518	rs->raid10_copies = raid10_copies;
1519
1520	/* Assume there are no metadata devices until the drives are parsed */
1521	rs->md.persistent = 0;
1522	rs->md.external = 1;
1523
1524	/* Check, if any invalid ctr arguments have been passed in for the raid level */
1525	return rs_check_for_valid_flags(rs);
1526}
1527
1528/* Set raid4/5/6 cache size */
1529static int rs_set_raid456_stripe_cache(struct raid_set *rs)
1530{
1531	int r;
1532	struct r5conf *conf;
1533	struct mddev *mddev = &rs->md;
1534	uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
1535	uint32_t nr_stripes = rs->stripe_cache_entries;
1536
1537	if (!rt_is_raid456(rs->raid_type)) {
1538		rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
1539		return -EINVAL;
1540	}
1541
1542	if (nr_stripes < min_stripes) {
1543		DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
1544		       nr_stripes, min_stripes);
1545		nr_stripes = min_stripes;
1546	}
1547
1548	conf = mddev->private;
1549	if (!conf) {
1550		rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
1551		return -EINVAL;
1552	}
1553
1554	/* Try setting number of stripes in raid456 stripe cache */
1555	if (conf->min_nr_stripes != nr_stripes) {
1556		r = raid5_set_cache_size(mddev, nr_stripes);
1557		if (r) {
1558			rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
1559			return r;
1560		}
1561
1562		DMINFO("%u stripe cache entries", nr_stripes);
1563	}
1564
1565	return 0;
1566}
1567
1568/* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1569static unsigned int mddev_data_stripes(struct raid_set *rs)
1570{
1571	return rs->md.raid_disks - rs->raid_type->parity_devs;
1572}
1573
1574/* Return # of data stripes of @rs (i.e. as of ctr) */
1575static unsigned int rs_data_stripes(struct raid_set *rs)
1576{
1577	return rs->raid_disks - rs->raid_type->parity_devs;
1578}
1579
1580/*
1581 * Retrieve rdev->sectors from any valid raid device of @rs
1582 * to allow userpace to pass in arbitray "- -" device tupples.
1583 */
1584static sector_t __rdev_sectors(struct raid_set *rs)
1585{
1586	int i;
1587
1588	for (i = 0; i < rs->md.raid_disks; i++) {
1589		struct md_rdev *rdev = &rs->dev[i].rdev;
1590
1591		if (!test_bit(Journal, &rdev->flags) &&
1592		    rdev->bdev && rdev->sectors)
1593			return rdev->sectors;
1594	}
1595
1596	return 0;
1597}
1598
1599/* Check that calculated dev_sectors fits all component devices. */
1600static int _check_data_dev_sectors(struct raid_set *rs)
1601{
1602	sector_t ds = ~0;
1603	struct md_rdev *rdev;
1604
1605	rdev_for_each(rdev, &rs->md)
1606		if (!test_bit(Journal, &rdev->flags) && rdev->bdev) {
1607			ds = min(ds, to_sector(i_size_read(rdev->bdev->bd_inode)));
1608			if (ds < rs->md.dev_sectors) {
1609				rs->ti->error = "Component device(s) too small";
1610				return -EINVAL;
1611			}
1612		}
1613
1614	return 0;
1615}
1616
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1617/* Calculate the sectors per device and per array used for @rs */
1618static int rs_set_dev_and_array_sectors(struct raid_set *rs, bool use_mddev)
1619{
1620	int delta_disks;
1621	unsigned int data_stripes;
 
1622	struct mddev *mddev = &rs->md;
1623	struct md_rdev *rdev;
1624	sector_t array_sectors = rs->ti->len, dev_sectors = rs->ti->len;
1625
1626	if (use_mddev) {
1627		delta_disks = mddev->delta_disks;
1628		data_stripes = mddev_data_stripes(rs);
1629	} else {
1630		delta_disks = rs->delta_disks;
1631		data_stripes = rs_data_stripes(rs);
1632	}
1633
1634	/* Special raid1 case w/o delta_disks support (yet) */
1635	if (rt_is_raid1(rs->raid_type))
1636		;
1637	else if (rt_is_raid10(rs->raid_type)) {
1638		if (rs->raid10_copies < 2 ||
1639		    delta_disks < 0) {
1640			rs->ti->error = "Bogus raid10 data copies or delta disks";
1641			return -EINVAL;
1642		}
1643
1644		dev_sectors *= rs->raid10_copies;
1645		if (sector_div(dev_sectors, data_stripes))
1646			goto bad;
1647
1648		array_sectors = (data_stripes + delta_disks) * dev_sectors;
1649		if (sector_div(array_sectors, rs->raid10_copies))
1650			goto bad;
1651
1652	} else if (sector_div(dev_sectors, data_stripes))
1653		goto bad;
1654
1655	else
1656		/* Striped layouts */
1657		array_sectors = (data_stripes + delta_disks) * dev_sectors;
1658
1659	rdev_for_each(rdev, mddev)
1660		if (!test_bit(Journal, &rdev->flags))
1661			rdev->sectors = dev_sectors;
1662
1663	mddev->array_sectors = array_sectors;
1664	mddev->dev_sectors = dev_sectors;
 
1665
1666	return _check_data_dev_sectors(rs);
1667bad:
1668	rs->ti->error = "Target length not divisible by number of data devices";
1669	return -EINVAL;
1670}
1671
1672/* Setup recovery on @rs */
1673static void __rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1674{
1675	/* raid0 does not recover */
1676	if (rs_is_raid0(rs))
1677		rs->md.recovery_cp = MaxSector;
1678	/*
1679	 * A raid6 set has to be recovered either
1680	 * completely or for the grown part to
1681	 * ensure proper parity and Q-Syndrome
1682	 */
1683	else if (rs_is_raid6(rs))
1684		rs->md.recovery_cp = dev_sectors;
1685	/*
1686	 * Other raid set types may skip recovery
1687	 * depending on the 'nosync' flag.
1688	 */
1689	else
1690		rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
1691				     ? MaxSector : dev_sectors;
1692}
1693
1694/* Setup recovery on @rs based on raid type, device size and 'nosync' flag */
1695static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1696{
1697	if (!dev_sectors)
1698		/* New raid set or 'sync' flag provided */
1699		__rs_setup_recovery(rs, 0);
1700	else if (dev_sectors == MaxSector)
1701		/* Prevent recovery */
1702		__rs_setup_recovery(rs, MaxSector);
1703	else if (__rdev_sectors(rs) < dev_sectors)
1704		/* Grown raid set */
1705		__rs_setup_recovery(rs, __rdev_sectors(rs));
1706	else
1707		__rs_setup_recovery(rs, MaxSector);
1708}
1709
1710static void do_table_event(struct work_struct *ws)
1711{
1712	struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1713
1714	smp_rmb(); /* Make sure we access most actual mddev properties */
1715	if (!rs_is_reshaping(rs)) {
 
 
 
 
 
 
1716		if (rs_is_raid10(rs))
1717			rs_set_rdev_sectors(rs);
 
 
1718		rs_set_capacity(rs);
1719	}
1720	dm_table_event(rs->ti->table);
1721}
1722
1723static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
1724{
1725	struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
1726
1727	return mddev_congested(&rs->md, bits);
1728}
1729
1730/*
1731 * Make sure a valid takover (level switch) is being requested on @rs
1732 *
1733 * Conversions of raid sets from one MD personality to another
1734 * have to conform to restrictions which are enforced here.
1735 */
1736static int rs_check_takeover(struct raid_set *rs)
1737{
1738	struct mddev *mddev = &rs->md;
1739	unsigned int near_copies;
1740
1741	if (rs->md.degraded) {
1742		rs->ti->error = "Can't takeover degraded raid set";
1743		return -EPERM;
1744	}
1745
1746	if (rs_is_reshaping(rs)) {
1747		rs->ti->error = "Can't takeover reshaping raid set";
1748		return -EPERM;
1749	}
1750
1751	switch (mddev->level) {
1752	case 0:
1753		/* raid0 -> raid1/5 with one disk */
1754		if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1755		    mddev->raid_disks == 1)
1756			return 0;
1757
1758		/* raid0 -> raid10 */
1759		if (mddev->new_level == 10 &&
1760		    !(rs->raid_disks % mddev->raid_disks))
1761			return 0;
1762
1763		/* raid0 with multiple disks -> raid4/5/6 */
1764		if (__within_range(mddev->new_level, 4, 6) &&
1765		    mddev->new_layout == ALGORITHM_PARITY_N &&
1766		    mddev->raid_disks > 1)
1767			return 0;
1768
1769		break;
1770
1771	case 10:
1772		/* Can't takeover raid10_offset! */
1773		if (__is_raid10_offset(mddev->layout))
1774			break;
1775
1776		near_copies = __raid10_near_copies(mddev->layout);
1777
1778		/* raid10* -> raid0 */
1779		if (mddev->new_level == 0) {
1780			/* Can takeover raid10_near with raid disks divisable by data copies! */
1781			if (near_copies > 1 &&
1782			    !(mddev->raid_disks % near_copies)) {
1783				mddev->raid_disks /= near_copies;
1784				mddev->delta_disks = mddev->raid_disks;
1785				return 0;
1786			}
1787
1788			/* Can takeover raid10_far */
1789			if (near_copies == 1 &&
1790			    __raid10_far_copies(mddev->layout) > 1)
1791				return 0;
1792
1793			break;
1794		}
1795
1796		/* raid10_{near,far} -> raid1 */
1797		if (mddev->new_level == 1 &&
1798		    max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1799			return 0;
1800
1801		/* raid10_{near,far} with 2 disks -> raid4/5 */
1802		if (__within_range(mddev->new_level, 4, 5) &&
1803		    mddev->raid_disks == 2)
1804			return 0;
1805		break;
1806
1807	case 1:
1808		/* raid1 with 2 disks -> raid4/5 */
1809		if (__within_range(mddev->new_level, 4, 5) &&
1810		    mddev->raid_disks == 2) {
1811			mddev->degraded = 1;
1812			return 0;
1813		}
1814
1815		/* raid1 -> raid0 */
1816		if (mddev->new_level == 0 &&
1817		    mddev->raid_disks == 1)
1818			return 0;
1819
1820		/* raid1 -> raid10 */
1821		if (mddev->new_level == 10)
1822			return 0;
1823		break;
1824
1825	case 4:
1826		/* raid4 -> raid0 */
1827		if (mddev->new_level == 0)
1828			return 0;
1829
1830		/* raid4 -> raid1/5 with 2 disks */
1831		if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1832		    mddev->raid_disks == 2)
1833			return 0;
1834
1835		/* raid4 -> raid5/6 with parity N */
1836		if (__within_range(mddev->new_level, 5, 6) &&
1837		    mddev->layout == ALGORITHM_PARITY_N)
1838			return 0;
1839		break;
1840
1841	case 5:
1842		/* raid5 with parity N -> raid0 */
1843		if (mddev->new_level == 0 &&
1844		    mddev->layout == ALGORITHM_PARITY_N)
1845			return 0;
1846
1847		/* raid5 with parity N -> raid4 */
1848		if (mddev->new_level == 4 &&
1849		    mddev->layout == ALGORITHM_PARITY_N)
1850			return 0;
1851
1852		/* raid5 with 2 disks -> raid1/4/10 */
1853		if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1854		    mddev->raid_disks == 2)
1855			return 0;
1856
1857		/* raid5_* ->  raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
1858		if (mddev->new_level == 6 &&
1859		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1860		      __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1861			return 0;
1862		break;
1863
1864	case 6:
1865		/* raid6 with parity N -> raid0 */
1866		if (mddev->new_level == 0 &&
1867		    mddev->layout == ALGORITHM_PARITY_N)
1868			return 0;
1869
1870		/* raid6 with parity N -> raid4 */
1871		if (mddev->new_level == 4 &&
1872		    mddev->layout == ALGORITHM_PARITY_N)
1873			return 0;
1874
1875		/* raid6_*_n with Q-Syndrome N -> raid5_* */
1876		if (mddev->new_level == 5 &&
1877		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1878		     __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1879			return 0;
 
1880
1881	default:
1882		break;
1883	}
1884
1885	rs->ti->error = "takeover not possible";
1886	return -EINVAL;
1887}
1888
1889/* True if @rs requested to be taken over */
1890static bool rs_takeover_requested(struct raid_set *rs)
1891{
1892	return rs->md.new_level != rs->md.level;
1893}
1894
 
 
 
 
 
 
 
 
1895/* True if @rs is requested to reshape by ctr */
1896static bool rs_reshape_requested(struct raid_set *rs)
1897{
1898	bool change;
1899	struct mddev *mddev = &rs->md;
1900
1901	if (rs_takeover_requested(rs))
1902		return false;
1903
1904	if (rs_is_raid0(rs))
1905		return false;
1906
1907	change = mddev->new_layout != mddev->layout ||
1908		 mddev->new_chunk_sectors != mddev->chunk_sectors ||
1909		 rs->delta_disks;
1910
1911	/* Historical case to support raid1 reshape without delta disks */
1912	if (rs_is_raid1(rs)) {
1913		if (rs->delta_disks)
1914			return !!rs->delta_disks;
1915
1916		return !change &&
1917		       mddev->raid_disks != rs->raid_disks;
1918	}
1919
1920	if (rs_is_raid10(rs))
1921		return change &&
1922		       !__is_raid10_far(mddev->new_layout) &&
1923		       rs->delta_disks >= 0;
1924
1925	return change;
1926}
1927
1928/*  Features */
1929#define	FEATURE_FLAG_SUPPORTS_V190	0x1 /* Supports extended superblock */
1930
1931/* State flags for sb->flags */
1932#define	SB_FLAG_RESHAPE_ACTIVE		0x1
1933#define	SB_FLAG_RESHAPE_BACKWARDS	0x2
1934
1935/*
1936 * This structure is never routinely used by userspace, unlike md superblocks.
1937 * Devices with this superblock should only ever be accessed via device-mapper.
1938 */
1939#define DM_RAID_MAGIC 0x64526D44
1940struct dm_raid_superblock {
1941	__le32 magic;		/* "DmRd" */
1942	__le32 compat_features;	/* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1943
1944	__le32 num_devices;	/* Number of devices in this raid set. (Max 64) */
1945	__le32 array_position;	/* The position of this drive in the raid set */
1946
1947	__le64 events;		/* Incremented by md when superblock updated */
1948	__le64 failed_devices;	/* Pre 1.9.0 part of bit field of devices to */
1949				/* indicate failures (see extension below) */
1950
1951	/*
1952	 * This offset tracks the progress of the repair or replacement of
1953	 * an individual drive.
1954	 */
1955	__le64 disk_recovery_offset;
1956
1957	/*
1958	 * This offset tracks the progress of the initial raid set
1959	 * synchronisation/parity calculation.
1960	 */
1961	__le64 array_resync_offset;
1962
1963	/*
1964	 * raid characteristics
1965	 */
1966	__le32 level;
1967	__le32 layout;
1968	__le32 stripe_sectors;
1969
1970	/********************************************************************
1971	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1972	 *
1973	 * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
1974	 */
1975
1976	__le32 flags; /* Flags defining array states for reshaping */
1977
1978	/*
1979	 * This offset tracks the progress of a raid
1980	 * set reshape in order to be able to restart it
1981	 */
1982	__le64 reshape_position;
1983
1984	/*
1985	 * These define the properties of the array in case of an interrupted reshape
1986	 */
1987	__le32 new_level;
1988	__le32 new_layout;
1989	__le32 new_stripe_sectors;
1990	__le32 delta_disks;
1991
1992	__le64 array_sectors; /* Array size in sectors */
1993
1994	/*
1995	 * Sector offsets to data on devices (reshaping).
1996	 * Needed to support out of place reshaping, thus
1997	 * not writing over any stripes whilst converting
1998	 * them from old to new layout
1999	 */
2000	__le64 data_offset;
2001	__le64 new_data_offset;
2002
2003	__le64 sectors; /* Used device size in sectors */
2004
2005	/*
2006	 * Additonal Bit field of devices indicating failures to support
2007	 * up to 256 devices with the 1.9.0 on-disk metadata format
2008	 */
2009	__le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
2010
2011	__le32 incompat_features;	/* Used to indicate any incompatible features */
2012
2013	/* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
2014} __packed;
2015
2016/*
2017 * Check for reshape constraints on raid set @rs:
2018 *
2019 * - reshape function non-existent
2020 * - degraded set
2021 * - ongoing recovery
2022 * - ongoing reshape
2023 *
2024 * Returns 0 if none or -EPERM if given constraint
2025 * and error message reference in @errmsg
2026 */
2027static int rs_check_reshape(struct raid_set *rs)
2028{
2029	struct mddev *mddev = &rs->md;
2030
2031	if (!mddev->pers || !mddev->pers->check_reshape)
2032		rs->ti->error = "Reshape not supported";
2033	else if (mddev->degraded)
2034		rs->ti->error = "Can't reshape degraded raid set";
2035	else if (rs_is_recovering(rs))
2036		rs->ti->error = "Convert request on recovering raid set prohibited";
2037	else if (rs_is_reshaping(rs))
2038		rs->ti->error = "raid set already reshaping!";
2039	else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
2040		rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
2041	else
2042		return 0;
2043
2044	return -EPERM;
2045}
2046
2047static int read_disk_sb(struct md_rdev *rdev, int size, bool force_reload)
2048{
2049	BUG_ON(!rdev->sb_page);
2050
2051	if (rdev->sb_loaded && !force_reload)
2052		return 0;
2053
2054	rdev->sb_loaded = 0;
2055
2056	if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, true)) {
2057		DMERR("Failed to read superblock of device at position %d",
2058		      rdev->raid_disk);
2059		md_error(rdev->mddev, rdev);
2060		set_bit(Faulty, &rdev->flags);
2061		return -EIO;
2062	}
2063
2064	rdev->sb_loaded = 1;
2065
2066	return 0;
2067}
2068
2069static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2070{
2071	failed_devices[0] = le64_to_cpu(sb->failed_devices);
2072	memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
2073
2074	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2075		int i = ARRAY_SIZE(sb->extended_failed_devices);
2076
2077		while (i--)
2078			failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
2079	}
2080}
2081
2082static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2083{
2084	int i = ARRAY_SIZE(sb->extended_failed_devices);
2085
2086	sb->failed_devices = cpu_to_le64(failed_devices[0]);
2087	while (i--)
2088		sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
2089}
2090
2091/*
2092 * Synchronize the superblock members with the raid set properties
2093 *
2094 * All superblock data is little endian.
2095 */
2096static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
2097{
2098	bool update_failed_devices = false;
2099	unsigned int i;
2100	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2101	struct dm_raid_superblock *sb;
2102	struct raid_set *rs = container_of(mddev, struct raid_set, md);
2103
2104	/* No metadata device, no superblock */
2105	if (!rdev->meta_bdev)
2106		return;
2107
2108	BUG_ON(!rdev->sb_page);
2109
2110	sb = page_address(rdev->sb_page);
2111
2112	sb_retrieve_failed_devices(sb, failed_devices);
2113
2114	for (i = 0; i < rs->raid_disks; i++)
2115		if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
2116			update_failed_devices = true;
2117			set_bit(i, (void *) failed_devices);
2118		}
2119
2120	if (update_failed_devices)
2121		sb_update_failed_devices(sb, failed_devices);
2122
2123	sb->magic = cpu_to_le32(DM_RAID_MAGIC);
2124	sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2125
2126	sb->num_devices = cpu_to_le32(mddev->raid_disks);
2127	sb->array_position = cpu_to_le32(rdev->raid_disk);
2128
2129	sb->events = cpu_to_le64(mddev->events);
2130
2131	sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
2132	sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
2133
2134	sb->level = cpu_to_le32(mddev->level);
2135	sb->layout = cpu_to_le32(mddev->layout);
2136	sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
2137
2138	/********************************************************************
2139	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
2140	 *
2141	 * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
2142	 */
2143	sb->new_level = cpu_to_le32(mddev->new_level);
2144	sb->new_layout = cpu_to_le32(mddev->new_layout);
2145	sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
2146
2147	sb->delta_disks = cpu_to_le32(mddev->delta_disks);
2148
2149	smp_rmb(); /* Make sure we access most recent reshape position */
2150	sb->reshape_position = cpu_to_le64(mddev->reshape_position);
2151	if (le64_to_cpu(sb->reshape_position) != MaxSector) {
2152		/* Flag ongoing reshape */
2153		sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
2154
2155		if (mddev->delta_disks < 0 || mddev->reshape_backwards)
2156			sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
2157	} else {
2158		/* Clear reshape flags */
2159		sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
2160	}
2161
2162	sb->array_sectors = cpu_to_le64(mddev->array_sectors);
2163	sb->data_offset = cpu_to_le64(rdev->data_offset);
2164	sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
2165	sb->sectors = cpu_to_le64(rdev->sectors);
2166	sb->incompat_features = cpu_to_le32(0);
2167
2168	/* Zero out the rest of the payload after the size of the superblock */
2169	memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
2170}
2171
2172/*
2173 * super_load
2174 *
2175 * This function creates a superblock if one is not found on the device
2176 * and will decide which superblock to use if there's a choice.
2177 *
2178 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
2179 */
2180static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
2181{
2182	int r;
2183	struct dm_raid_superblock *sb;
2184	struct dm_raid_superblock *refsb;
2185	uint64_t events_sb, events_refsb;
2186
2187	r = read_disk_sb(rdev, rdev->sb_size, false);
2188	if (r)
2189		return r;
2190
2191	sb = page_address(rdev->sb_page);
2192
2193	/*
2194	 * Two cases that we want to write new superblocks and rebuild:
2195	 * 1) New device (no matching magic number)
2196	 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
2197	 */
2198	if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
2199	    (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
2200		super_sync(rdev->mddev, rdev);
2201
2202		set_bit(FirstUse, &rdev->flags);
2203		sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2204
2205		/* Force writing of superblocks to disk */
2206		set_bit(MD_SB_CHANGE_DEVS, &rdev->mddev->sb_flags);
2207
2208		/* Any superblock is better than none, choose that if given */
2209		return refdev ? 0 : 1;
2210	}
2211
2212	if (!refdev)
2213		return 1;
2214
2215	events_sb = le64_to_cpu(sb->events);
2216
2217	refsb = page_address(refdev->sb_page);
2218	events_refsb = le64_to_cpu(refsb->events);
2219
2220	return (events_sb > events_refsb) ? 1 : 0;
2221}
2222
2223static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
2224{
2225	int role;
2226	unsigned int d;
2227	struct mddev *mddev = &rs->md;
2228	uint64_t events_sb;
2229	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2230	struct dm_raid_superblock *sb;
2231	uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
2232	struct md_rdev *r;
2233	struct dm_raid_superblock *sb2;
2234
2235	sb = page_address(rdev->sb_page);
2236	events_sb = le64_to_cpu(sb->events);
2237
2238	/*
2239	 * Initialise to 1 if this is a new superblock.
2240	 */
2241	mddev->events = events_sb ? : 1;
2242
2243	mddev->reshape_position = MaxSector;
2244
2245	mddev->raid_disks = le32_to_cpu(sb->num_devices);
2246	mddev->level = le32_to_cpu(sb->level);
2247	mddev->layout = le32_to_cpu(sb->layout);
2248	mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
2249
2250	/*
2251	 * Reshaping is supported, e.g. reshape_position is valid
2252	 * in superblock and superblock content is authoritative.
2253	 */
2254	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2255		/* Superblock is authoritative wrt given raid set layout! */
2256		mddev->new_level = le32_to_cpu(sb->new_level);
2257		mddev->new_layout = le32_to_cpu(sb->new_layout);
2258		mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
2259		mddev->delta_disks = le32_to_cpu(sb->delta_disks);
2260		mddev->array_sectors = le64_to_cpu(sb->array_sectors);
2261
2262		/* raid was reshaping and got interrupted */
2263		if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2264			if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2265				DMERR("Reshape requested but raid set is still reshaping");
2266				return -EINVAL;
2267			}
2268
2269			if (mddev->delta_disks < 0 ||
2270			    (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2271				mddev->reshape_backwards = 1;
2272			else
2273				mddev->reshape_backwards = 0;
2274
2275			mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2276			rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
2277		}
2278
2279	} else {
2280		/*
2281		 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2282		 */
2283		struct raid_type *rt_cur = get_raid_type_by_ll(mddev->level, mddev->layout);
2284		struct raid_type *rt_new = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
2285
2286		if (rs_takeover_requested(rs)) {
2287			if (rt_cur && rt_new)
2288				DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",
2289				      rt_cur->name, rt_new->name);
2290			else
2291				DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");
2292			return -EINVAL;
2293		} else if (rs_reshape_requested(rs)) {
2294			DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");
2295			if (mddev->layout != mddev->new_layout) {
2296				if (rt_cur && rt_new)
2297					DMERR("	 current layout %s vs new layout %s",
2298					      rt_cur->name, rt_new->name);
2299				else
2300					DMERR("	 current layout 0x%X vs new layout 0x%X",
2301					      le32_to_cpu(sb->layout), mddev->new_layout);
2302			}
2303			if (mddev->chunk_sectors != mddev->new_chunk_sectors)
2304				DMERR("	 current stripe sectors %u vs new stripe sectors %u",
2305				      mddev->chunk_sectors, mddev->new_chunk_sectors);
2306			if (rs->delta_disks)
2307				DMERR("	 current %u disks vs new %u disks",
2308				      mddev->raid_disks, mddev->raid_disks + rs->delta_disks);
2309			if (rs_is_raid10(rs)) {
2310				DMERR("	 Old layout: %s w/ %u copies",
2311				      raid10_md_layout_to_format(mddev->layout),
2312				      raid10_md_layout_to_copies(mddev->layout));
2313				DMERR("	 New layout: %s w/ %u copies",
2314				      raid10_md_layout_to_format(mddev->new_layout),
2315				      raid10_md_layout_to_copies(mddev->new_layout));
2316			}
2317			return -EINVAL;
2318		}
2319
2320		DMINFO("Discovered old metadata format; upgrading to extended metadata format");
2321	}
2322
2323	if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2324		mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2325
2326	/*
2327	 * During load, we set FirstUse if a new superblock was written.
2328	 * There are two reasons we might not have a superblock:
2329	 * 1) The raid set is brand new - in which case, all of the
2330	 *    devices must have their In_sync bit set.	Also,
2331	 *    recovery_cp must be 0, unless forced.
2332	 * 2) This is a new device being added to an old raid set
2333	 *    and the new device needs to be rebuilt - in which
2334	 *    case the In_sync bit will /not/ be set and
2335	 *    recovery_cp must be MaxSector.
2336	 * 3) This is/are a new device(s) being added to an old
2337	 *    raid set during takeover to a higher raid level
2338	 *    to provide capacity for redundancy or during reshape
2339	 *    to add capacity to grow the raid set.
2340	 */
2341	d = 0;
2342	rdev_for_each(r, mddev) {
2343		if (test_bit(Journal, &rdev->flags))
2344			continue;
2345
2346		if (test_bit(FirstUse, &r->flags))
2347			new_devs++;
2348
2349		if (!test_bit(In_sync, &r->flags)) {
2350			DMINFO("Device %d specified for rebuild; clearing superblock",
2351				r->raid_disk);
2352			rebuilds++;
2353
2354			if (test_bit(FirstUse, &r->flags))
2355				rebuild_and_new++;
2356		}
2357
2358		d++;
2359	}
2360
2361	if (new_devs == rs->raid_disks || !rebuilds) {
2362		/* Replace a broken device */
2363		if (new_devs == 1 && !rs->delta_disks)
2364			;
2365		if (new_devs == rs->raid_disks) {
2366			DMINFO("Superblocks created for new raid set");
2367			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2368		} else if (new_devs != rebuilds &&
2369			   new_devs != rs->delta_disks) {
2370			DMERR("New device injected into existing raid set without "
2371			      "'delta_disks' or 'rebuild' parameter specified");
2372			return -EINVAL;
2373		}
2374	} else if (new_devs && new_devs != rebuilds) {
2375		DMERR("%u 'rebuild' devices cannot be injected into"
2376		      " a raid set with %u other first-time devices",
2377		      rebuilds, new_devs);
2378		return -EINVAL;
2379	} else if (rebuilds) {
2380		if (rebuild_and_new && rebuilds != rebuild_and_new) {
2381			DMERR("new device%s provided without 'rebuild'",
2382			      new_devs > 1 ? "s" : "");
2383			return -EINVAL;
2384		} else if (!test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && rs_is_recovering(rs)) {
2385			DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2386			      (unsigned long long) mddev->recovery_cp);
2387			return -EINVAL;
2388		} else if (rs_is_reshaping(rs)) {
2389			DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2390			      (unsigned long long) mddev->reshape_position);
2391			return -EINVAL;
2392		}
2393	}
2394
2395	/*
2396	 * Now we set the Faulty bit for those devices that are
2397	 * recorded in the superblock as failed.
2398	 */
2399	sb_retrieve_failed_devices(sb, failed_devices);
2400	rdev_for_each(r, mddev) {
2401		if (test_bit(Journal, &rdev->flags) ||
2402		    !r->sb_page)
2403			continue;
2404		sb2 = page_address(r->sb_page);
2405		sb2->failed_devices = 0;
2406		memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2407
2408		/*
2409		 * Check for any device re-ordering.
2410		 */
2411		if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2412			role = le32_to_cpu(sb2->array_position);
2413			if (role < 0)
2414				continue;
2415
2416			if (role != r->raid_disk) {
2417				if (rs_is_raid10(rs) && __is_raid10_near(mddev->layout)) {
2418					if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2419					    rs->raid_disks % rs->raid10_copies) {
2420						rs->ti->error =
2421							"Cannot change raid10 near set to odd # of devices!";
2422						return -EINVAL;
2423					}
2424
2425					sb2->array_position = cpu_to_le32(r->raid_disk);
2426
2427				} else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2428					   !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2429					   !rt_is_raid1(rs->raid_type)) {
2430					rs->ti->error = "Cannot change device positions in raid set";
2431					return -EINVAL;
2432				}
2433
2434				DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2435			}
2436
2437			/*
2438			 * Partial recovery is performed on
2439			 * returning failed devices.
2440			 */
2441			if (test_bit(role, (void *) failed_devices))
2442				set_bit(Faulty, &r->flags);
2443		}
2444	}
2445
2446	return 0;
2447}
2448
2449static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2450{
2451	struct mddev *mddev = &rs->md;
2452	struct dm_raid_superblock *sb;
2453
2454	if (rs_is_raid0(rs) || !rdev->sb_page || rdev->raid_disk < 0)
2455		return 0;
2456
2457	sb = page_address(rdev->sb_page);
2458
2459	/*
2460	 * If mddev->events is not set, we know we have not yet initialized
2461	 * the array.
2462	 */
2463	if (!mddev->events && super_init_validation(rs, rdev))
2464		return -EINVAL;
2465
2466	if (le32_to_cpu(sb->compat_features) &&
2467	    le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2468		rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2469		return -EINVAL;
2470	}
2471
2472	if (sb->incompat_features) {
2473		rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2474		return -EINVAL;
2475	}
2476
2477	/* Enable bitmap creation for RAID levels != 0 */
2478	mddev->bitmap_info.offset = (rt_is_raid0(rs->raid_type) || rs->journal_dev.dev) ? 0 : to_sector(4096);
2479	mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2480
2481	if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2482		/*
2483		 * Retrieve rdev size stored in superblock to be prepared for shrink.
2484		 * Check extended superblock members are present otherwise the size
2485		 * will not be set!
2486		 */
2487		if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190)
2488			rdev->sectors = le64_to_cpu(sb->sectors);
2489
2490		rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2491		if (rdev->recovery_offset == MaxSector)
2492			set_bit(In_sync, &rdev->flags);
2493		/*
2494		 * If no reshape in progress -> we're recovering single
2495		 * disk(s) and have to set the device(s) to out-of-sync
2496		 */
2497		else if (!rs_is_reshaping(rs))
2498			clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2499	}
2500
2501	/*
2502	 * If a device comes back, set it as not In_sync and no longer faulty.
2503	 */
2504	if (test_and_clear_bit(Faulty, &rdev->flags)) {
2505		rdev->recovery_offset = 0;
2506		clear_bit(In_sync, &rdev->flags);
2507		rdev->saved_raid_disk = rdev->raid_disk;
2508	}
2509
2510	/* Reshape support -> restore repective data offsets */
2511	rdev->data_offset = le64_to_cpu(sb->data_offset);
2512	rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2513
2514	return 0;
2515}
2516
2517/*
2518 * Analyse superblocks and select the freshest.
2519 */
2520static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2521{
2522	int r;
2523	struct md_rdev *rdev, *freshest;
2524	struct mddev *mddev = &rs->md;
2525
2526	freshest = NULL;
2527	rdev_for_each(rdev, mddev) {
2528		if (test_bit(Journal, &rdev->flags))
2529			continue;
2530
2531		if (!rdev->meta_bdev)
2532			continue;
2533
2534		/* Set superblock offset/size for metadata device. */
2535		rdev->sb_start = 0;
2536		rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
2537		if (rdev->sb_size < sizeof(struct dm_raid_superblock) || rdev->sb_size > PAGE_SIZE) {
2538			DMERR("superblock size of a logical block is no longer valid");
2539			return -EINVAL;
2540		}
2541
2542		/*
2543		 * Skipping super_load due to CTR_FLAG_SYNC will cause
2544		 * the array to undergo initialization again as
2545		 * though it were new.	This is the intended effect
2546		 * of the "sync" directive.
2547		 *
2548		 * With reshaping capability added, we must ensure that
2549		 * that the "sync" directive is disallowed during the reshape.
2550		 */
2551		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2552			continue;
2553
2554		r = super_load(rdev, freshest);
2555
2556		switch (r) {
2557		case 1:
2558			freshest = rdev;
2559			break;
2560		case 0:
2561			break;
2562		default:
2563			/* This is a failure to read the superblock from the metadata device. */
2564			/*
2565			 * We have to keep any raid0 data/metadata device pairs or
2566			 * the MD raid0 personality will fail to start the array.
2567			 */
2568			if (rs_is_raid0(rs))
2569				continue;
2570
2571			/*
2572			 * We keep the dm_devs to be able to emit the device tuple
2573			 * properly on the table line in raid_status() (rather than
2574			 * mistakenly acting as if '- -' got passed into the constructor).
2575			 *
2576			 * The rdev has to stay on the same_set list to allow for
2577			 * the attempt to restore faulty devices on second resume.
2578			 */
2579			rdev->raid_disk = rdev->saved_raid_disk = -1;
2580			break;
2581		}
2582	}
2583
2584	if (!freshest)
2585		return 0;
2586
2587	/*
2588	 * Validation of the freshest device provides the source of
2589	 * validation for the remaining devices.
2590	 */
2591	rs->ti->error = "Unable to assemble array: Invalid superblocks";
2592	if (super_validate(rs, freshest))
2593		return -EINVAL;
2594
2595	if (validate_raid_redundancy(rs)) {
2596		rs->ti->error = "Insufficient redundancy to activate array";
2597		return -EINVAL;
2598	}
2599
2600	rdev_for_each(rdev, mddev)
2601		if (!test_bit(Journal, &rdev->flags) &&
2602		    rdev != freshest &&
2603		    super_validate(rs, rdev))
2604			return -EINVAL;
2605	return 0;
2606}
2607
2608/*
2609 * Adjust data_offset and new_data_offset on all disk members of @rs
2610 * for out of place reshaping if requested by contructor
2611 *
2612 * We need free space at the beginning of each raid disk for forward
2613 * and at the end for backward reshapes which userspace has to provide
2614 * via remapping/reordering of space.
2615 */
2616static int rs_adjust_data_offsets(struct raid_set *rs)
2617{
2618	sector_t data_offset = 0, new_data_offset = 0;
2619	struct md_rdev *rdev;
2620
2621	/* Constructor did not request data offset change */
2622	if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2623		if (!rs_is_reshapable(rs))
2624			goto out;
2625
2626		return 0;
2627	}
2628
2629	/* HM FIXME: get In_Sync raid_dev? */
2630	rdev = &rs->dev[0].rdev;
2631
2632	if (rs->delta_disks < 0) {
2633		/*
2634		 * Removing disks (reshaping backwards):
2635		 *
2636		 * - before reshape: data is at offset 0 and free space
2637		 *		     is at end of each component LV
2638		 *
2639		 * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2640		 */
2641		data_offset = 0;
2642		new_data_offset = rs->data_offset;
2643
2644	} else if (rs->delta_disks > 0) {
2645		/*
2646		 * Adding disks (reshaping forwards):
2647		 *
2648		 * - before reshape: data is at offset rs->data_offset != 0 and
2649		 *		     free space is at begin of each component LV
2650		 *
2651		 * - after reshape: data is at offset 0 on each component LV
2652		 */
2653		data_offset = rs->data_offset;
2654		new_data_offset = 0;
2655
2656	} else {
2657		/*
2658		 * User space passes in 0 for data offset after having removed reshape space
2659		 *
2660		 * - or - (data offset != 0)
2661		 *
2662		 * Changing RAID layout or chunk size -> toggle offsets
2663		 *
2664		 * - before reshape: data is at offset rs->data_offset 0 and
2665		 *		     free space is at end of each component LV
2666		 *		     -or-
2667		 *                   data is at offset rs->data_offset != 0 and
2668		 *		     free space is at begin of each component LV
2669		 *
2670		 * - after reshape: data is at offset 0 if it was at offset != 0
2671		 *                  or at offset != 0 if it was at offset 0
2672		 *                  on each component LV
2673		 *
2674		 */
2675		data_offset = rs->data_offset ? rdev->data_offset : 0;
2676		new_data_offset = data_offset ? 0 : rs->data_offset;
2677		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2678	}
2679
2680	/*
2681	 * Make sure we got a minimum amount of free sectors per device
2682	 */
2683	if (rs->data_offset &&
2684	    to_sector(i_size_read(rdev->bdev->bd_inode)) - rs->md.dev_sectors < MIN_FREE_RESHAPE_SPACE) {
2685		rs->ti->error = data_offset ? "No space for forward reshape" :
2686					      "No space for backward reshape";
2687		return -ENOSPC;
2688	}
2689out:
2690	/*
2691	 * Raise recovery_cp in case data_offset != 0 to
2692	 * avoid false recovery positives in the constructor.
2693	 */
2694	if (rs->md.recovery_cp < rs->md.dev_sectors)
2695		rs->md.recovery_cp += rs->dev[0].rdev.data_offset;
2696
2697	/* Adjust data offsets on all rdevs but on any raid4/5/6 journal device */
2698	rdev_for_each(rdev, &rs->md) {
2699		if (!test_bit(Journal, &rdev->flags)) {
2700			rdev->data_offset = data_offset;
2701			rdev->new_data_offset = new_data_offset;
2702		}
2703	}
2704
2705	return 0;
2706}
2707
2708/* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2709static void __reorder_raid_disk_indexes(struct raid_set *rs)
2710{
2711	int i = 0;
2712	struct md_rdev *rdev;
2713
2714	rdev_for_each(rdev, &rs->md) {
2715		if (!test_bit(Journal, &rdev->flags)) {
2716			rdev->raid_disk = i++;
2717			rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2718		}
2719	}
2720}
2721
2722/*
2723 * Setup @rs for takeover by a different raid level
2724 */
2725static int rs_setup_takeover(struct raid_set *rs)
2726{
2727	struct mddev *mddev = &rs->md;
2728	struct md_rdev *rdev;
2729	unsigned int d = mddev->raid_disks = rs->raid_disks;
2730	sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2731
2732	if (rt_is_raid10(rs->raid_type)) {
2733		if (rs_is_raid0(rs)) {
2734			/* Userpace reordered disks -> adjust raid_disk indexes */
2735			__reorder_raid_disk_indexes(rs);
2736
2737			/* raid0 -> raid10_far layout */
2738			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2739								   rs->raid10_copies);
2740		} else if (rs_is_raid1(rs))
2741			/* raid1 -> raid10_near layout */
2742			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2743								   rs->raid_disks);
2744		else
2745			return -EINVAL;
2746
2747	}
2748
2749	clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2750	mddev->recovery_cp = MaxSector;
2751
2752	while (d--) {
2753		rdev = &rs->dev[d].rdev;
2754
2755		if (test_bit(d, (void *) rs->rebuild_disks)) {
2756			clear_bit(In_sync, &rdev->flags);
2757			clear_bit(Faulty, &rdev->flags);
2758			mddev->recovery_cp = rdev->recovery_offset = 0;
2759			/* Bitmap has to be created when we do an "up" takeover */
2760			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2761		}
2762
2763		rdev->new_data_offset = new_data_offset;
2764	}
2765
2766	return 0;
2767}
2768
2769/* Prepare @rs for reshape */
2770static int rs_prepare_reshape(struct raid_set *rs)
2771{
2772	bool reshape;
2773	struct mddev *mddev = &rs->md;
2774
2775	if (rs_is_raid10(rs)) {
2776		if (rs->raid_disks != mddev->raid_disks &&
2777		    __is_raid10_near(mddev->layout) &&
2778		    rs->raid10_copies &&
2779		    rs->raid10_copies != __raid10_near_copies(mddev->layout)) {
2780			/*
2781			 * raid disk have to be multiple of data copies to allow this conversion,
2782			 *
2783			 * This is actually not a reshape it is a
2784			 * rebuild of any additional mirrors per group
2785			 */
2786			if (rs->raid_disks % rs->raid10_copies) {
2787				rs->ti->error = "Can't reshape raid10 mirror groups";
2788				return -EINVAL;
2789			}
2790
2791			/* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2792			__reorder_raid_disk_indexes(rs);
2793			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2794								   rs->raid10_copies);
2795			mddev->new_layout = mddev->layout;
2796			reshape = false;
2797		} else
2798			reshape = true;
2799
2800	} else if (rs_is_raid456(rs))
2801		reshape = true;
2802
2803	else if (rs_is_raid1(rs)) {
2804		if (rs->delta_disks) {
2805			/* Process raid1 via delta_disks */
2806			mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
2807			reshape = true;
2808		} else {
2809			/* Process raid1 without delta_disks */
2810			mddev->raid_disks = rs->raid_disks;
2811			reshape = false;
2812		}
2813	} else {
2814		rs->ti->error = "Called with bogus raid type";
2815		return -EINVAL;
2816	}
2817
2818	if (reshape) {
2819		set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2820		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2821	} else if (mddev->raid_disks < rs->raid_disks)
2822		/* Create new superblocks and bitmaps, if any new disks */
2823		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2824
2825	return 0;
2826}
2827
2828/* Get reshape sectors from data_offsets or raid set */
2829static sector_t _get_reshape_sectors(struct raid_set *rs)
2830{
2831	struct md_rdev *rdev;
2832	sector_t reshape_sectors = 0;
2833
2834	rdev_for_each(rdev, &rs->md)
2835		if (!test_bit(Journal, &rdev->flags)) {
2836			reshape_sectors = (rdev->data_offset > rdev->new_data_offset) ?
2837					rdev->data_offset - rdev->new_data_offset :
2838					rdev->new_data_offset - rdev->data_offset;
2839			break;
2840		}
2841
2842	return max(reshape_sectors, (sector_t) rs->data_offset);
2843}
2844
2845/*
2846 *
2847 * - change raid layout
2848 * - change chunk size
2849 * - add disks
2850 * - remove disks
2851 */
2852static int rs_setup_reshape(struct raid_set *rs)
2853{
2854	int r = 0;
2855	unsigned int cur_raid_devs, d;
2856	sector_t reshape_sectors = _get_reshape_sectors(rs);
2857	struct mddev *mddev = &rs->md;
2858	struct md_rdev *rdev;
2859
2860	mddev->delta_disks = rs->delta_disks;
2861	cur_raid_devs = mddev->raid_disks;
2862
2863	/* Ignore impossible layout change whilst adding/removing disks */
2864	if (mddev->delta_disks &&
2865	    mddev->layout != mddev->new_layout) {
2866		DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2867		mddev->new_layout = mddev->layout;
2868	}
2869
2870	/*
2871	 * Adjust array size:
2872	 *
2873	 * - in case of adding disk(s), array size has
2874	 *   to grow after the disk adding reshape,
2875	 *   which'll hapen in the event handler;
2876	 *   reshape will happen forward, so space has to
2877	 *   be available at the beginning of each disk
2878	 *
2879	 * - in case of removing disk(s), array size
2880	 *   has to shrink before starting the reshape,
2881	 *   which'll happen here;
2882	 *   reshape will happen backward, so space has to
2883	 *   be available at the end of each disk
2884	 *
2885	 * - data_offset and new_data_offset are
2886	 *   adjusted for aforementioned out of place
2887	 *   reshaping based on userspace passing in
2888	 *   the "data_offset <sectors>" key/value
2889	 *   pair via the constructor
2890	 */
2891
2892	/* Add disk(s) */
2893	if (rs->delta_disks > 0) {
2894		/* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2895		for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2896			rdev = &rs->dev[d].rdev;
2897			clear_bit(In_sync, &rdev->flags);
2898
2899			/*
2900			 * save_raid_disk needs to be -1, or recovery_offset will be set to 0
2901			 * by md, which'll store that erroneously in the superblock on reshape
2902			 */
2903			rdev->saved_raid_disk = -1;
2904			rdev->raid_disk = d;
2905
2906			rdev->sectors = mddev->dev_sectors;
2907			rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
2908		}
2909
2910		mddev->reshape_backwards = 0; /* adding disk(s) -> forward reshape */
2911
2912	/* Remove disk(s) */
2913	} else if (rs->delta_disks < 0) {
2914		r = rs_set_dev_and_array_sectors(rs, true);
2915		mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2916
2917	/* Change layout and/or chunk size */
2918	} else {
2919		/*
2920		 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2921		 *
2922		 * keeping number of disks and do layout change ->
2923		 *
2924		 * toggle reshape_backward depending on data_offset:
2925		 *
2926		 * - free space upfront -> reshape forward
2927		 *
2928		 * - free space at the end -> reshape backward
2929		 *
2930		 *
2931		 * This utilizes free reshape space avoiding the need
2932		 * for userspace to move (parts of) LV segments in
2933		 * case of layout/chunksize change  (for disk
2934		 * adding/removing reshape space has to be at
2935		 * the proper address (see above with delta_disks):
2936		 *
2937		 * add disk(s)   -> begin
2938		 * remove disk(s)-> end
2939		 */
2940		mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2941	}
2942
2943	/*
2944	 * Adjust device size for forward reshape
2945	 * because md_finish_reshape() reduces it.
2946	 */
2947	if (!mddev->reshape_backwards)
2948		rdev_for_each(rdev, &rs->md)
2949			if (!test_bit(Journal, &rdev->flags))
2950				rdev->sectors += reshape_sectors;
2951
2952	return r;
2953}
2954
2955/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2956 * Enable/disable discard support on RAID set depending on
2957 * RAID level and discard properties of underlying RAID members.
2958 */
2959static void configure_discard_support(struct raid_set *rs)
2960{
2961	int i;
2962	bool raid456;
2963	struct dm_target *ti = rs->ti;
2964
2965	/*
2966	 * XXX: RAID level 4,5,6 require zeroing for safety.
2967	 */
2968	raid456 = rs_is_raid456(rs);
2969
2970	for (i = 0; i < rs->raid_disks; i++) {
2971		struct request_queue *q;
2972
2973		if (!rs->dev[i].rdev.bdev)
2974			continue;
2975
2976		q = bdev_get_queue(rs->dev[i].rdev.bdev);
2977		if (!q || !blk_queue_discard(q))
2978			return;
2979
2980		if (raid456) {
2981			if (!devices_handle_discard_safely) {
2982				DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2983				DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2984				return;
2985			}
2986		}
2987	}
2988
2989	ti->num_discard_bios = 1;
2990}
2991
2992/*
2993 * Construct a RAID0/1/10/4/5/6 mapping:
2994 * Args:
2995 *	<raid_type> <#raid_params> <raid_params>{0,}	\
2996 *	<#raid_devs> [<meta_dev1> <dev1>]{1,}
2997 *
2998 * <raid_params> varies by <raid_type>.	 See 'parse_raid_params' for
2999 * details on possible <raid_params>.
3000 *
3001 * Userspace is free to initialize the metadata devices, hence the superblocks to
3002 * enforce recreation based on the passed in table parameters.
3003 *
3004 */
3005static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
3006{
3007	int r;
3008	bool resize = false;
3009	struct raid_type *rt;
3010	unsigned int num_raid_params, num_raid_devs;
3011	sector_t calculated_dev_sectors, rdev_sectors, reshape_sectors;
3012	struct raid_set *rs = NULL;
3013	const char *arg;
3014	struct rs_layout rs_layout;
3015	struct dm_arg_set as = { argc, argv }, as_nrd;
3016	struct dm_arg _args[] = {
3017		{ 0, as.argc, "Cannot understand number of raid parameters" },
3018		{ 1, 254, "Cannot understand number of raid devices parameters" }
3019	};
3020
3021	/* Must have <raid_type> */
3022	arg = dm_shift_arg(&as);
3023	if (!arg) {
3024		ti->error = "No arguments";
3025		return -EINVAL;
3026	}
3027
3028	rt = get_raid_type(arg);
3029	if (!rt) {
3030		ti->error = "Unrecognised raid_type";
3031		return -EINVAL;
3032	}
3033
3034	/* Must have <#raid_params> */
3035	if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
3036		return -EINVAL;
3037
3038	/* number of raid device tupples <meta_dev data_dev> */
3039	as_nrd = as;
3040	dm_consume_args(&as_nrd, num_raid_params);
3041	_args[1].max = (as_nrd.argc - 1) / 2;
3042	if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
3043		return -EINVAL;
3044
3045	if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
3046		ti->error = "Invalid number of supplied raid devices";
3047		return -EINVAL;
3048	}
3049
3050	rs = raid_set_alloc(ti, rt, num_raid_devs);
3051	if (IS_ERR(rs))
3052		return PTR_ERR(rs);
3053
3054	r = parse_raid_params(rs, &as, num_raid_params);
3055	if (r)
3056		goto bad;
3057
3058	r = parse_dev_params(rs, &as);
3059	if (r)
3060		goto bad;
3061
3062	rs->md.sync_super = super_sync;
3063
3064	/*
3065	 * Calculate ctr requested array and device sizes to allow
3066	 * for superblock analysis needing device sizes defined.
3067	 *
3068	 * Any existing superblock will overwrite the array and device sizes
3069	 */
3070	r = rs_set_dev_and_array_sectors(rs, false);
3071	if (r)
3072		goto bad;
3073
3074	calculated_dev_sectors = rs->md.dev_sectors;
 
 
3075
3076	/*
3077	 * Backup any new raid set level, layout, ...
3078	 * requested to be able to compare to superblock
3079	 * members for conversion decisions.
3080	 */
3081	rs_config_backup(rs, &rs_layout);
3082
3083	r = analyse_superblocks(ti, rs);
3084	if (r)
3085		goto bad;
3086
 
 
3087	rdev_sectors = __rdev_sectors(rs);
3088	if (!rdev_sectors) {
3089		ti->error = "Invalid rdev size";
3090		r = -EINVAL;
3091		goto bad;
3092	}
3093
3094
3095	reshape_sectors = _get_reshape_sectors(rs);
3096	if (calculated_dev_sectors != rdev_sectors)
3097		resize = calculated_dev_sectors != (reshape_sectors ? rdev_sectors - reshape_sectors : rdev_sectors);
 
 
 
3098
3099	INIT_WORK(&rs->md.event_work, do_table_event);
3100	ti->private = rs;
3101	ti->num_flush_bios = 1;
 
3102
3103	/* Restore any requested new layout for conversion decision */
3104	rs_config_restore(rs, &rs_layout);
3105
3106	/*
3107	 * Now that we have any superblock metadata available,
3108	 * check for new, recovering, reshaping, to be taken over,
3109	 * to be reshaped or an existing, unchanged raid set to
3110	 * run in sequence.
3111	 */
3112	if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
3113		/* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
3114		if (rs_is_raid6(rs) &&
3115		    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
3116			ti->error = "'nosync' not allowed for new raid6 set";
3117			r = -EINVAL;
3118			goto bad;
3119		}
3120		rs_setup_recovery(rs, 0);
3121		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3122		rs_set_new(rs);
3123	} else if (rs_is_recovering(rs)) {
3124		/* Rebuild particular devices */
3125		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
3126			set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3127			rs_setup_recovery(rs, MaxSector);
3128		}
3129		/* A recovering raid set may be resized */
3130		; /* skip setup rs */
3131	} else if (rs_is_reshaping(rs)) {
3132		/* Have to reject size change request during reshape */
3133		if (resize) {
3134			ti->error = "Can't resize a reshaping raid set";
3135			r = -EPERM;
3136			goto bad;
3137		}
3138		/* skip setup rs */
3139	} else if (rs_takeover_requested(rs)) {
3140		if (rs_is_reshaping(rs)) {
3141			ti->error = "Can't takeover a reshaping raid set";
3142			r = -EPERM;
3143			goto bad;
3144		}
3145
3146		/* We can't takeover a journaled raid4/5/6 */
3147		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3148			ti->error = "Can't takeover a journaled raid4/5/6 set";
3149			r = -EPERM;
3150			goto bad;
3151		}
3152
3153		/*
3154		 * If a takeover is needed, userspace sets any additional
3155		 * devices to rebuild and we can check for a valid request here.
3156		 *
3157		 * If acceptible, set the level to the new requested
3158		 * one, prohibit requesting recovery, allow the raid
3159		 * set to run and store superblocks during resume.
3160		 */
3161		r = rs_check_takeover(rs);
3162		if (r)
3163			goto bad;
3164
3165		r = rs_setup_takeover(rs);
3166		if (r)
3167			goto bad;
3168
3169		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3170		/* Takeover ain't recovery, so disable recovery */
3171		rs_setup_recovery(rs, MaxSector);
3172		rs_set_new(rs);
3173	} else if (rs_reshape_requested(rs)) {
 
 
 
3174		/*
3175		 * No need to check for 'ongoing' takeover here, because takeover
3176		 * is an instant operation as oposed to an ongoing reshape.
3177		 */
3178
3179		/* We can't reshape a journaled raid4/5/6 */
3180		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3181			ti->error = "Can't reshape a journaled raid4/5/6 set";
3182			r = -EPERM;
3183			goto bad;
3184		}
3185
3186		/* Out-of-place space has to be available to allow for a reshape unless raid1! */
3187		if (reshape_sectors || rs_is_raid1(rs)) {
3188			/*
3189			  * We can only prepare for a reshape here, because the
3190			  * raid set needs to run to provide the repective reshape
3191			  * check functions via its MD personality instance.
3192			  *
3193			  * So do the reshape check after md_run() succeeded.
3194			  */
3195			r = rs_prepare_reshape(rs);
3196			if (r)
3197				goto bad;
3198
3199			/* Reshaping ain't recovery, so disable recovery */
3200			rs_setup_recovery(rs, MaxSector);
3201		}
3202		rs_set_cur(rs);
3203	} else {
 
3204		/* May not set recovery when a device rebuild is requested */
3205		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
3206			rs_setup_recovery(rs, MaxSector);
3207			set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3208		} else
3209			rs_setup_recovery(rs, test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ?
3210					      0 : (resize ? calculated_dev_sectors : MaxSector));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3211		rs_set_cur(rs);
3212	}
3213
3214	/* If constructor requested it, change data and new_data offsets */
3215	r = rs_adjust_data_offsets(rs);
3216	if (r)
3217		goto bad;
3218
 
 
 
3219	/* Start raid set read-only and assumed clean to change in raid_resume() */
3220	rs->md.ro = 1;
3221	rs->md.in_sync = 1;
3222
3223	/* Keep array frozen */
3224	set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
3225
3226	/* Has to be held on running the array */
3227	mddev_lock_nointr(&rs->md);
 
 
 
 
3228	r = md_run(&rs->md);
3229	rs->md.in_sync = 0; /* Assume already marked dirty */
3230	if (r) {
3231		ti->error = "Failed to run raid array";
3232		mddev_unlock(&rs->md);
3233		goto bad;
3234	}
3235
3236	r = md_start(&rs->md);
3237
3238	if (r) {
3239		ti->error = "Failed to start raid array";
3240		mddev_unlock(&rs->md);
3241		goto bad_md_start;
3242	}
3243
3244	rs->callbacks.congested_fn = raid_is_congested;
3245	dm_table_add_target_callbacks(ti->table, &rs->callbacks);
3246
3247	/* If raid4/5/6 journal mode explicitly requested (only possible with journal dev) -> set it */
3248	if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
3249		r = r5c_journal_mode_set(&rs->md, rs->journal_dev.mode);
3250		if (r) {
3251			ti->error = "Failed to set raid4/5/6 journal mode";
3252			mddev_unlock(&rs->md);
3253			goto bad_journal_mode_set;
3254		}
3255	}
3256
3257	mddev_suspend(&rs->md);
3258	set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags);
3259
3260	/* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
3261	if (rs_is_raid456(rs)) {
3262		r = rs_set_raid456_stripe_cache(rs);
3263		if (r)
3264			goto bad_stripe_cache;
3265	}
3266
3267	/* Now do an early reshape check */
3268	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3269		r = rs_check_reshape(rs);
3270		if (r)
3271			goto bad_check_reshape;
3272
3273		/* Restore new, ctr requested layout to perform check */
3274		rs_config_restore(rs, &rs_layout);
3275
3276		if (rs->md.pers->start_reshape) {
3277			r = rs->md.pers->check_reshape(&rs->md);
3278			if (r) {
3279				ti->error = "Reshape check failed";
3280				goto bad_check_reshape;
3281			}
3282		}
3283	}
3284
3285	/* Disable/enable discard support on raid set. */
3286	configure_discard_support(rs);
3287
3288	mddev_unlock(&rs->md);
3289	return 0;
3290
3291bad_md_start:
3292bad_journal_mode_set:
3293bad_stripe_cache:
3294bad_check_reshape:
3295	md_stop(&rs->md);
 
3296bad:
3297	raid_set_free(rs);
3298
3299	return r;
3300}
3301
3302static void raid_dtr(struct dm_target *ti)
3303{
3304	struct raid_set *rs = ti->private;
3305
3306	list_del_init(&rs->callbacks.list);
3307	md_stop(&rs->md);
 
 
 
 
3308	raid_set_free(rs);
3309}
3310
3311static int raid_map(struct dm_target *ti, struct bio *bio)
3312{
3313	struct raid_set *rs = ti->private;
3314	struct mddev *mddev = &rs->md;
3315
3316	/*
3317	 * If we're reshaping to add disk(s)), ti->len and
3318	 * mddev->array_sectors will differ during the process
3319	 * (ti->len > mddev->array_sectors), so we have to requeue
3320	 * bios with addresses > mddev->array_sectors here or
3321	 * there will occur accesses past EOD of the component
3322	 * data images thus erroring the raid set.
3323	 */
3324	if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
3325		return DM_MAPIO_REQUEUE;
3326
3327	md_handle_request(mddev, bio);
 
3328
3329	return DM_MAPIO_SUBMITTED;
3330}
3331
3332/* Return sync state string for @state */
3333enum sync_state { st_frozen, st_reshape, st_resync, st_check, st_repair, st_recover, st_idle };
3334static const char *sync_str(enum sync_state state)
3335{
3336	/* Has to be in above sync_state order! */
3337	static const char *sync_strs[] = {
3338		"frozen",
3339		"reshape",
3340		"resync",
3341		"check",
3342		"repair",
3343		"recover",
3344		"idle"
3345	};
3346
3347	return __within_range(state, 0, ARRAY_SIZE(sync_strs) - 1) ? sync_strs[state] : "undef";
3348};
3349
3350/* Return enum sync_state for @mddev derived from @recovery flags */
3351static enum sync_state decipher_sync_action(struct mddev *mddev, unsigned long recovery)
3352{
3353	if (test_bit(MD_RECOVERY_FROZEN, &recovery))
3354		return st_frozen;
3355
3356	/* The MD sync thread can be done with io or be interrupted but still be running */
3357	if (!test_bit(MD_RECOVERY_DONE, &recovery) &&
3358	    (test_bit(MD_RECOVERY_RUNNING, &recovery) ||
3359	     (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery)))) {
3360		if (test_bit(MD_RECOVERY_RESHAPE, &recovery))
3361			return st_reshape;
3362
3363		if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
3364			if (!test_bit(MD_RECOVERY_REQUESTED, &recovery))
3365				return st_resync;
3366			if (test_bit(MD_RECOVERY_CHECK, &recovery))
3367				return st_check;
3368			return st_repair;
3369		}
3370
3371		if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3372			return st_recover;
3373
3374		if (mddev->reshape_position != MaxSector)
3375			return st_reshape;
3376	}
3377
3378	return st_idle;
3379}
3380
3381/*
3382 * Return status string for @rdev
3383 *
3384 * Status characters:
3385 *
3386 *  'D' = Dead/Failed raid set component or raid4/5/6 journal device
3387 *  'a' = Alive but not in-sync raid set component _or_ alive raid4/5/6 'write_back' journal device
3388 *  'A' = Alive and in-sync raid set component _or_ alive raid4/5/6 'write_through' journal device
3389 *  '-' = Non-existing device (i.e. uspace passed '- -' into the ctr)
3390 */
3391static const char *__raid_dev_status(struct raid_set *rs, struct md_rdev *rdev)
3392{
3393	if (!rdev->bdev)
3394		return "-";
3395	else if (test_bit(Faulty, &rdev->flags))
3396		return "D";
3397	else if (test_bit(Journal, &rdev->flags))
3398		return (rs->journal_dev.mode == R5C_JOURNAL_MODE_WRITE_THROUGH) ? "A" : "a";
3399	else if (test_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags) ||
3400		 (!test_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags) &&
3401		  !test_bit(In_sync, &rdev->flags)))
3402		return "a";
3403	else
3404		return "A";
3405}
3406
3407/* Helper to return resync/reshape progress for @rs and runtime flags for raid set in sync / resynching */
3408static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery,
3409				sector_t resync_max_sectors)
3410{
3411	sector_t r;
3412	enum sync_state state;
3413	struct mddev *mddev = &rs->md;
3414
3415	clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3416	clear_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3417
3418	if (rs_is_raid0(rs)) {
3419		r = resync_max_sectors;
3420		set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3421
3422	} else {
3423		state = decipher_sync_action(mddev, recovery);
3424
3425		if (state == st_idle && !test_bit(MD_RECOVERY_INTR, &recovery))
3426			r = mddev->recovery_cp;
3427		else
3428			r = mddev->curr_resync_completed;
3429
3430		if (state == st_idle && r >= resync_max_sectors) {
3431			/*
3432			 * Sync complete.
3433			 */
3434			/* In case we have finished recovering, the array is in sync. */
3435			if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3436				set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3437
3438		} else if (state == st_recover)
3439			/*
3440			 * In case we are recovering, the array is not in sync
3441			 * and health chars should show the recovering legs.
 
 
3442			 */
3443			;
3444		else if (state == st_resync)
3445			/*
3446			 * If "resync" is occurring, the raid set
3447			 * is or may be out of sync hence the health
3448			 * characters shall be 'a'.
3449			 */
3450			set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3451		else if (state == st_reshape)
3452			/*
3453			 * If "reshape" is occurring, the raid set
3454			 * is or may be out of sync hence the health
3455			 * characters shall be 'a'.
3456			 */
3457			set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3458
3459		else if (state == st_check || state == st_repair)
3460			/*
3461			 * If "check" or "repair" is occurring, the raid set has
3462			 * undergone an initial sync and the health characters
3463			 * should not be 'a' anymore.
3464			 */
3465			set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3466
3467		else {
3468			struct md_rdev *rdev;
3469
3470			/*
3471			 * We are idle and recovery is needed, prevent 'A' chars race
3472			 * caused by components still set to in-sync by constructor.
3473			 */
3474			if (test_bit(MD_RECOVERY_NEEDED, &recovery))
3475				set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3476
 
3477			/*
3478			 * The raid set may be doing an initial sync, or it may
3479			 * be rebuilding individual components.	 If all the
3480			 * devices are In_sync, then it is the raid set that is
3481			 * being initialized.
3482			 */
 
 
3483			set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3484			rdev_for_each(rdev, mddev)
3485				if (!test_bit(Journal, &rdev->flags) &&
3486				    !test_bit(In_sync, &rdev->flags)) {
3487					clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3488					break;
3489				}
3490		}
3491	}
3492
3493	return min(r, resync_max_sectors);
3494}
3495
3496/* Helper to return @dev name or "-" if !@dev */
3497static const char *__get_dev_name(struct dm_dev *dev)
3498{
3499	return dev ? dev->name : "-";
3500}
3501
3502static void raid_status(struct dm_target *ti, status_type_t type,
3503			unsigned int status_flags, char *result, unsigned int maxlen)
3504{
3505	struct raid_set *rs = ti->private;
3506	struct mddev *mddev = &rs->md;
3507	struct r5conf *conf = mddev->private;
3508	int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3509	unsigned long recovery;
3510	unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3511	unsigned int sz = 0;
3512	unsigned int rebuild_disks;
3513	unsigned int write_mostly_params = 0;
3514	sector_t progress, resync_max_sectors, resync_mismatches;
3515	const char *sync_action;
3516	struct raid_type *rt;
3517
3518	switch (type) {
3519	case STATUSTYPE_INFO:
3520		/* *Should* always succeed */
3521		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3522		if (!rt)
3523			return;
3524
3525		DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3526
3527		/* Access most recent mddev properties for status output */
3528		smp_rmb();
3529		recovery = rs->md.recovery;
3530		/* Get sensible max sectors even if raid set not yet started */
3531		resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3532				      mddev->resync_max_sectors : mddev->dev_sectors;
3533		progress = rs_get_progress(rs, recovery, resync_max_sectors);
3534		resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
 
 
3535				    atomic64_read(&mddev->resync_mismatches) : 0;
3536		sync_action = sync_str(decipher_sync_action(&rs->md, recovery));
3537
3538		/* HM FIXME: do we want another state char for raid0? It shows 'D'/'A'/'-' now */
3539		for (i = 0; i < rs->raid_disks; i++)
3540			DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3541
3542		/*
3543		 * In-sync/Reshape ratio:
3544		 *  The in-sync ratio shows the progress of:
3545		 *   - Initializing the raid set
3546		 *   - Rebuilding a subset of devices of the raid set
3547		 *  The user can distinguish between the two by referring
3548		 *  to the status characters.
3549		 *
3550		 *  The reshape ratio shows the progress of
3551		 *  changing the raid layout or the number of
3552		 *  disks of a raid set
3553		 */
3554		DMEMIT(" %llu/%llu", (unsigned long long) progress,
3555				     (unsigned long long) resync_max_sectors);
3556
3557		/*
3558		 * v1.5.0+:
3559		 *
3560		 * Sync action:
3561		 *   See Documentation/admin-guide/device-mapper/dm-raid.rst for
3562		 *   information on each of these states.
3563		 */
3564		DMEMIT(" %s", sync_action);
3565
3566		/*
3567		 * v1.5.0+:
3568		 *
3569		 * resync_mismatches/mismatch_cnt
3570		 *   This field shows the number of discrepancies found when
3571		 *   performing a "check" of the raid set.
3572		 */
3573		DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3574
3575		/*
3576		 * v1.9.0+:
3577		 *
3578		 * data_offset (needed for out of space reshaping)
3579		 *   This field shows the data offset into the data
3580		 *   image LV where the first stripes data starts.
3581		 *
3582		 * We keep data_offset equal on all raid disks of the set,
3583		 * so retrieving it from the first raid disk is sufficient.
3584		 */
3585		DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
3586
3587		/*
3588		 * v1.10.0+:
3589		 */
3590		DMEMIT(" %s", test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags) ?
3591			      __raid_dev_status(rs, &rs->journal_dev.rdev) : "-");
3592		break;
3593
3594	case STATUSTYPE_TABLE:
3595		/* Report the table line string you would use to construct this raid set */
3596
3597		/* Calculate raid parameter count */
3598		for (i = 0; i < rs->raid_disks; i++)
3599			if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3600				write_mostly_params += 2;
3601		rebuild_disks = memweight(rs->rebuild_disks, DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks));
3602		raid_param_cnt += rebuild_disks * 2 +
3603				  write_mostly_params +
 
 
 
 
 
3604				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3605				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2 +
3606				  (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags) ? 2 : 0) +
3607				  (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags) ? 2 : 0);
3608
3609		/* Emit table line */
3610		/* This has to be in the documented order for userspace! */
3611		DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3612		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3613			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
3614		if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3615			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3616		if (rebuild_disks)
3617			for (i = 0; i < rs->raid_disks; i++)
3618				if (test_bit(rs->dev[i].rdev.raid_disk, (void *) rs->rebuild_disks))
3619					DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD),
3620							 rs->dev[i].rdev.raid_disk);
3621		if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3622			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3623					  mddev->bitmap_info.daemon_sleep);
3624		if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3625			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3626					 mddev->sync_speed_min);
3627		if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3628			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3629					 mddev->sync_speed_max);
3630		if (write_mostly_params)
3631			for (i = 0; i < rs->raid_disks; i++)
3632				if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3633					DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3634					       rs->dev[i].rdev.raid_disk);
3635		if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3636			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3637					  mddev->bitmap_info.max_write_behind);
3638		if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3639			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3640					 max_nr_stripes);
3641		if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3642			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3643					   (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3644		if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3645			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3646					 raid10_md_layout_to_copies(mddev->layout));
3647		if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3648			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3649					 raid10_md_layout_to_format(mddev->layout));
3650		if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3651			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3652					 max(rs->delta_disks, mddev->delta_disks));
3653		if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3654			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3655					   (unsigned long long) rs->data_offset);
3656		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags))
3657			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV),
3658					__get_dev_name(rs->journal_dev.dev));
3659		if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags))
3660			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE),
3661					 md_journal_mode_to_dm_raid(rs->journal_dev.mode));
3662		DMEMIT(" %d", rs->raid_disks);
3663		for (i = 0; i < rs->raid_disks; i++)
3664			DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
3665					 __get_dev_name(rs->dev[i].data_dev));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3666	}
3667}
3668
3669static int raid_message(struct dm_target *ti, unsigned int argc, char **argv,
3670			char *result, unsigned maxlen)
3671{
3672	struct raid_set *rs = ti->private;
3673	struct mddev *mddev = &rs->md;
 
3674
3675	if (!mddev->pers || !mddev->pers->sync_request)
3676		return -EINVAL;
3677
3678	if (!strcasecmp(argv[0], "frozen"))
3679		set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3680	else
3681		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3682
3683	if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
3684		if (mddev->sync_thread) {
3685			set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3686			md_reap_sync_thread(mddev);
3687		}
3688	} else if (decipher_sync_action(mddev, mddev->recovery) != st_idle)
 
 
 
 
 
 
 
 
 
 
 
 
3689		return -EBUSY;
3690	else if (!strcasecmp(argv[0], "resync"))
3691		; /* MD_RECOVERY_NEEDED set below */
3692	else if (!strcasecmp(argv[0], "recover"))
3693		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3694	else {
3695		if (!strcasecmp(argv[0], "check")) {
3696			set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3697			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3698			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3699		} else if (!strcasecmp(argv[0], "repair")) {
3700			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3701			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3702		} else
3703			return -EINVAL;
3704	}
3705	if (mddev->ro == 2) {
3706		/* A write to sync_action is enough to justify
3707		 * canceling read-auto mode
3708		 */
3709		mddev->ro = 0;
3710		if (!mddev->suspended && mddev->sync_thread)
3711			md_wakeup_thread(mddev->sync_thread);
3712	}
3713	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3714	if (!mddev->suspended && mddev->thread)
3715		md_wakeup_thread(mddev->thread);
3716
3717	return 0;
3718}
3719
3720static int raid_iterate_devices(struct dm_target *ti,
3721				iterate_devices_callout_fn fn, void *data)
3722{
3723	struct raid_set *rs = ti->private;
3724	unsigned int i;
3725	int r = 0;
3726
3727	for (i = 0; !r && i < rs->md.raid_disks; i++)
3728		if (rs->dev[i].data_dev)
3729			r = fn(ti,
3730				 rs->dev[i].data_dev,
3731				 0, /* No offset on data devs */
3732				 rs->md.dev_sectors,
3733				 data);
3734
3735	return r;
3736}
3737
3738static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3739{
3740	struct raid_set *rs = ti->private;
3741	unsigned int chunk_size_bytes = to_bytes(rs->md.chunk_sectors);
3742
3743	blk_limits_io_min(limits, chunk_size_bytes);
3744	blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs));
 
 
 
 
 
 
3745
3746	/*
3747	 * RAID1 and RAID10 personalities require bio splitting,
3748	 * RAID0/4/5/6 don't and process large discard bios properly.
3749	 */
3750	if (rs_is_raid1(rs) || rs_is_raid10(rs)) {
3751		limits->discard_granularity = chunk_size_bytes;
3752		limits->max_discard_sectors = rs->md.chunk_sectors;
3753	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3754}
3755
3756static void raid_postsuspend(struct dm_target *ti)
3757{
3758	struct raid_set *rs = ti->private;
3759
3760	if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
3761		/* Writes have to be stopped before suspending to avoid deadlocks. */
3762		if (!test_bit(MD_RECOVERY_FROZEN, &rs->md.recovery))
3763			md_stop_writes(&rs->md);
3764
3765		mddev_lock_nointr(&rs->md);
3766		mddev_suspend(&rs->md);
3767		mddev_unlock(&rs->md);
3768	}
3769}
3770
3771static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3772{
3773	int i;
3774	uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];
3775	unsigned long flags;
3776	bool cleared = false;
3777	struct dm_raid_superblock *sb;
3778	struct mddev *mddev = &rs->md;
3779	struct md_rdev *r;
3780
3781	/* RAID personalities have to provide hot add/remove methods or we need to bail out. */
3782	if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)
3783		return;
3784
3785	memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));
3786
3787	for (i = 0; i < mddev->raid_disks; i++) {
3788		r = &rs->dev[i].rdev;
3789		/* HM FIXME: enhance journal device recovery processing */
3790		if (test_bit(Journal, &r->flags))
3791			continue;
3792
3793		if (test_bit(Faulty, &r->flags) &&
3794		    r->meta_bdev && !read_disk_sb(r, r->sb_size, true)) {
3795			DMINFO("Faulty %s device #%d has readable super block."
3796			       "  Attempting to revive it.",
3797			       rs->raid_type->name, i);
3798
3799			/*
3800			 * Faulty bit may be set, but sometimes the array can
3801			 * be suspended before the personalities can respond
3802			 * by removing the device from the array (i.e. calling
3803			 * 'hot_remove_disk').	If they haven't yet removed
3804			 * the failed device, its 'raid_disk' number will be
3805			 * '>= 0' - meaning we must call this function
3806			 * ourselves.
3807			 */
3808			flags = r->flags;
3809			clear_bit(In_sync, &r->flags); /* Mandatory for hot remove. */
3810			if (r->raid_disk >= 0) {
3811				if (mddev->pers->hot_remove_disk(mddev, r)) {
3812					/* Failed to revive this device, try next */
3813					r->flags = flags;
3814					continue;
3815				}
3816			} else
3817				r->raid_disk = r->saved_raid_disk = i;
3818
3819			clear_bit(Faulty, &r->flags);
3820			clear_bit(WriteErrorSeen, &r->flags);
3821
3822			if (mddev->pers->hot_add_disk(mddev, r)) {
3823				/* Failed to revive this device, try next */
3824				r->raid_disk = r->saved_raid_disk = -1;
3825				r->flags = flags;
3826			} else {
3827				clear_bit(In_sync, &r->flags);
3828				r->recovery_offset = 0;
3829				set_bit(i, (void *) cleared_failed_devices);
3830				cleared = true;
3831			}
3832		}
3833	}
3834
3835	/* If any failed devices could be cleared, update all sbs failed_devices bits */
3836	if (cleared) {
3837		uint64_t failed_devices[DISKS_ARRAY_ELEMS];
3838
3839		rdev_for_each(r, &rs->md) {
3840			if (test_bit(Journal, &r->flags))
3841				continue;
3842
3843			sb = page_address(r->sb_page);
3844			sb_retrieve_failed_devices(sb, failed_devices);
3845
3846			for (i = 0; i < DISKS_ARRAY_ELEMS; i++)
3847				failed_devices[i] &= ~cleared_failed_devices[i];
3848
3849			sb_update_failed_devices(sb, failed_devices);
3850		}
3851	}
3852}
3853
3854static int __load_dirty_region_bitmap(struct raid_set *rs)
3855{
3856	int r = 0;
3857
3858	/* Try loading the bitmap unless "raid0", which does not have one */
3859	if (!rs_is_raid0(rs) &&
3860	    !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
3861		r = md_bitmap_load(&rs->md);
 
 
3862		if (r)
3863			DMERR("Failed to load bitmap");
3864	}
3865
3866	return r;
3867}
3868
3869/* Enforce updating all superblocks */
3870static void rs_update_sbs(struct raid_set *rs)
3871{
3872	struct mddev *mddev = &rs->md;
3873	int ro = mddev->ro;
3874
3875	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
3876	mddev->ro = 0;
3877	md_update_sb(mddev, 1);
3878	mddev->ro = ro;
3879}
3880
3881/*
3882 * Reshape changes raid algorithm of @rs to new one within personality
3883 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3884 * disks from a raid set thus growing/shrinking it or resizes the set
3885 *
3886 * Call mddev_lock_nointr() before!
3887 */
3888static int rs_start_reshape(struct raid_set *rs)
3889{
3890	int r;
3891	struct mddev *mddev = &rs->md;
3892	struct md_personality *pers = mddev->pers;
3893
3894	/* Don't allow the sync thread to work until the table gets reloaded. */
3895	set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
3896
3897	r = rs_setup_reshape(rs);
3898	if (r)
3899		return r;
3900
3901	/*
3902	 * Check any reshape constraints enforced by the personalility
3903	 *
3904	 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3905	 */
3906	r = pers->check_reshape(mddev);
3907	if (r) {
3908		rs->ti->error = "pers->check_reshape() failed";
3909		return r;
3910	}
3911
3912	/*
3913	 * Personality may not provide start reshape method in which
3914	 * case check_reshape above has already covered everything
3915	 */
3916	if (pers->start_reshape) {
3917		r = pers->start_reshape(mddev);
3918		if (r) {
3919			rs->ti->error = "pers->start_reshape() failed";
3920			return r;
3921		}
3922	}
3923
3924	/*
3925	 * Now reshape got set up, update superblocks to
3926	 * reflect the fact so that a table reload will
3927	 * access proper superblock content in the ctr.
3928	 */
3929	rs_update_sbs(rs);
3930
3931	return 0;
3932}
3933
3934static int raid_preresume(struct dm_target *ti)
3935{
3936	int r;
3937	struct raid_set *rs = ti->private;
3938	struct mddev *mddev = &rs->md;
3939
3940	/* This is a resume after a suspend of the set -> it's already started. */
3941	if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
3942		return 0;
3943
 
 
 
 
 
3944	/*
3945	 * The superblocks need to be updated on disk if the
3946	 * array is new or new devices got added (thus zeroed
3947	 * out by userspace) or __load_dirty_region_bitmap
3948	 * will overwrite them in core with old data or fail.
3949	 */
3950	if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
3951		rs_update_sbs(rs);
3952
3953	/* Load the bitmap from disk unless raid0 */
3954	r = __load_dirty_region_bitmap(rs);
3955	if (r)
3956		return r;
3957
3958	/* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */
 
 
 
 
 
 
 
 
3959	if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
3960	    mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) {
3961		r = md_bitmap_resize(mddev->bitmap, mddev->dev_sectors,
3962				     to_bytes(rs->requested_bitmap_chunk_sectors), 0);
 
 
 
 
3963		if (r)
3964			DMERR("Failed to resize bitmap");
3965	}
3966
3967	/* Check for any resize/reshape on @rs and adjust/initiate */
3968	/* Be prepared for mddev_resume() in raid_resume() */
3969	set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3970	if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
3971		set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3972		mddev->resync_min = mddev->recovery_cp;
 
 
3973	}
3974
3975	/* Check for any reshape request unless new raid set */
3976	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3977		/* Initiate a reshape. */
3978		rs_set_rdev_sectors(rs);
3979		mddev_lock_nointr(mddev);
3980		r = rs_start_reshape(rs);
3981		mddev_unlock(mddev);
3982		if (r)
3983			DMWARN("Failed to check/start reshape, continuing without change");
3984		r = 0;
3985	}
3986
3987	return r;
3988}
3989
3990static void raid_resume(struct dm_target *ti)
3991{
3992	struct raid_set *rs = ti->private;
3993	struct mddev *mddev = &rs->md;
3994
3995	if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
3996		/*
3997		 * A secondary resume while the device is active.
3998		 * Take this opportunity to check whether any failed
3999		 * devices are reachable again.
4000		 */
 
4001		attempt_restore_of_faulty_devices(rs);
 
4002	}
4003
4004	if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
4005		/* Only reduce raid set size before running a disk removing reshape. */
4006		if (mddev->delta_disks < 0)
4007			rs_set_capacity(rs);
4008
4009		mddev_lock_nointr(mddev);
4010		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
 
 
 
4011		mddev->ro = 0;
4012		mddev->in_sync = 0;
4013		mddev_resume(mddev);
4014		mddev_unlock(mddev);
4015	}
4016}
4017
4018static struct target_type raid_target = {
4019	.name = "raid",
4020	.version = {1, 14, 0},
4021	.module = THIS_MODULE,
4022	.ctr = raid_ctr,
4023	.dtr = raid_dtr,
4024	.map = raid_map,
4025	.status = raid_status,
4026	.message = raid_message,
4027	.iterate_devices = raid_iterate_devices,
4028	.io_hints = raid_io_hints,
 
 
4029	.postsuspend = raid_postsuspend,
4030	.preresume = raid_preresume,
4031	.resume = raid_resume,
4032};
4033
4034static int __init dm_raid_init(void)
4035{
4036	DMINFO("Loading target version %u.%u.%u",
4037	       raid_target.version[0],
4038	       raid_target.version[1],
4039	       raid_target.version[2]);
4040	return dm_register_target(&raid_target);
4041}
4042
4043static void __exit dm_raid_exit(void)
4044{
4045	dm_unregister_target(&raid_target);
4046}
4047
4048module_init(dm_raid_init);
4049module_exit(dm_raid_exit);
4050
4051module_param(devices_handle_discard_safely, bool, 0644);
4052MODULE_PARM_DESC(devices_handle_discard_safely,
4053		 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
4054
4055MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
4056MODULE_ALIAS("dm-raid0");
4057MODULE_ALIAS("dm-raid1");
4058MODULE_ALIAS("dm-raid10");
4059MODULE_ALIAS("dm-raid4");
4060MODULE_ALIAS("dm-raid5");
4061MODULE_ALIAS("dm-raid6");
4062MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
4063MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
4064MODULE_LICENSE("GPL");
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2010-2011 Neil Brown
   4 * Copyright (C) 2010-2018 Red Hat, Inc. All rights reserved.
   5 *
   6 * This file is released under the GPL.
   7 */
   8
   9#include <linux/slab.h>
  10#include <linux/module.h>
  11
  12#include "md.h"
  13#include "raid1.h"
  14#include "raid5.h"
  15#include "raid10.h"
  16#include "md-bitmap.h"
  17
  18#include <linux/device-mapper.h>
  19
  20#define DM_MSG_PREFIX "raid"
  21#define	MAX_RAID_DEVICES	253 /* md-raid kernel limit */
  22
  23/*
  24 * Minimum sectors of free reshape space per raid device
  25 */
  26#define	MIN_FREE_RESHAPE_SPACE to_sector(4*4096)
  27
  28/*
  29 * Minimum journal space 4 MiB in sectors.
  30 */
  31#define	MIN_RAID456_JOURNAL_SPACE (4*2048)
  32
  33static bool devices_handle_discard_safely;
  34
  35/*
  36 * The following flags are used by dm-raid to set up the array state.
  37 * They must be cleared before md_run is called.
  38 */
  39#define FirstUse 10		/* rdev flag */
  40
  41struct raid_dev {
  42	/*
  43	 * Two DM devices, one to hold metadata and one to hold the
  44	 * actual data/parity.	The reason for this is to not confuse
  45	 * ti->len and give more flexibility in altering size and
  46	 * characteristics.
  47	 *
  48	 * While it is possible for this device to be associated
  49	 * with a different physical device than the data_dev, it
  50	 * is intended for it to be the same.
  51	 *    |--------- Physical Device ---------|
  52	 *    |- meta_dev -|------ data_dev ------|
  53	 */
  54	struct dm_dev *meta_dev;
  55	struct dm_dev *data_dev;
  56	struct md_rdev rdev;
  57};
  58
  59/*
  60 * Bits for establishing rs->ctr_flags
  61 *
  62 * 1 = no flag value
  63 * 2 = flag with value
  64 */
  65#define __CTR_FLAG_SYNC			0  /* 1 */ /* Not with raid0! */
  66#define __CTR_FLAG_NOSYNC		1  /* 1 */ /* Not with raid0! */
  67#define __CTR_FLAG_REBUILD		2  /* 2 */ /* Not with raid0! */
  68#define __CTR_FLAG_DAEMON_SLEEP		3  /* 2 */ /* Not with raid0! */
  69#define __CTR_FLAG_MIN_RECOVERY_RATE	4  /* 2 */ /* Not with raid0! */
  70#define __CTR_FLAG_MAX_RECOVERY_RATE	5  /* 2 */ /* Not with raid0! */
  71#define __CTR_FLAG_MAX_WRITE_BEHIND	6  /* 2 */ /* Only with raid1! */
  72#define __CTR_FLAG_WRITE_MOSTLY		7  /* 2 */ /* Only with raid1! */
  73#define __CTR_FLAG_STRIPE_CACHE		8  /* 2 */ /* Only with raid4/5/6! */
  74#define __CTR_FLAG_REGION_SIZE		9  /* 2 */ /* Not with raid0! */
  75#define __CTR_FLAG_RAID10_COPIES	10 /* 2 */ /* Only with raid10 */
  76#define __CTR_FLAG_RAID10_FORMAT	11 /* 2 */ /* Only with raid10 */
  77/* New for v1.9.0 */
  78#define __CTR_FLAG_DELTA_DISKS		12 /* 2 */ /* Only with reshapable raid1/4/5/6/10! */
  79#define __CTR_FLAG_DATA_OFFSET		13 /* 2 */ /* Only with reshapable raid4/5/6/10! */
  80#define __CTR_FLAG_RAID10_USE_NEAR_SETS 14 /* 2 */ /* Only with raid10! */
  81
  82/* New for v1.10.0 */
  83#define __CTR_FLAG_JOURNAL_DEV		15 /* 2 */ /* Only with raid4/5/6 (journal device)! */
  84
  85/* New for v1.11.1 */
  86#define __CTR_FLAG_JOURNAL_MODE		16 /* 2 */ /* Only with raid4/5/6 (journal mode)! */
  87
  88/*
  89 * Flags for rs->ctr_flags field.
  90 */
  91#define CTR_FLAG_SYNC			(1 << __CTR_FLAG_SYNC)
  92#define CTR_FLAG_NOSYNC			(1 << __CTR_FLAG_NOSYNC)
  93#define CTR_FLAG_REBUILD		(1 << __CTR_FLAG_REBUILD)
  94#define CTR_FLAG_DAEMON_SLEEP		(1 << __CTR_FLAG_DAEMON_SLEEP)
  95#define CTR_FLAG_MIN_RECOVERY_RATE	(1 << __CTR_FLAG_MIN_RECOVERY_RATE)
  96#define CTR_FLAG_MAX_RECOVERY_RATE	(1 << __CTR_FLAG_MAX_RECOVERY_RATE)
  97#define CTR_FLAG_MAX_WRITE_BEHIND	(1 << __CTR_FLAG_MAX_WRITE_BEHIND)
  98#define CTR_FLAG_WRITE_MOSTLY		(1 << __CTR_FLAG_WRITE_MOSTLY)
  99#define CTR_FLAG_STRIPE_CACHE		(1 << __CTR_FLAG_STRIPE_CACHE)
 100#define CTR_FLAG_REGION_SIZE		(1 << __CTR_FLAG_REGION_SIZE)
 101#define CTR_FLAG_RAID10_COPIES		(1 << __CTR_FLAG_RAID10_COPIES)
 102#define CTR_FLAG_RAID10_FORMAT		(1 << __CTR_FLAG_RAID10_FORMAT)
 103#define CTR_FLAG_DELTA_DISKS		(1 << __CTR_FLAG_DELTA_DISKS)
 104#define CTR_FLAG_DATA_OFFSET		(1 << __CTR_FLAG_DATA_OFFSET)
 105#define CTR_FLAG_RAID10_USE_NEAR_SETS	(1 << __CTR_FLAG_RAID10_USE_NEAR_SETS)
 106#define CTR_FLAG_JOURNAL_DEV		(1 << __CTR_FLAG_JOURNAL_DEV)
 107#define CTR_FLAG_JOURNAL_MODE		(1 << __CTR_FLAG_JOURNAL_MODE)
 108
 109/*
 110 * Definitions of various constructor flags to
 111 * be used in checks of valid / invalid flags
 112 * per raid level.
 113 */
 114/* Define all any sync flags */
 115#define	CTR_FLAGS_ANY_SYNC		(CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)
 116
 117/* Define flags for options without argument (e.g. 'nosync') */
 118#define	CTR_FLAG_OPTIONS_NO_ARGS	(CTR_FLAGS_ANY_SYNC | \
 119					 CTR_FLAG_RAID10_USE_NEAR_SETS)
 120
 121/* Define flags for options with one argument (e.g. 'delta_disks +2') */
 122#define CTR_FLAG_OPTIONS_ONE_ARG (CTR_FLAG_REBUILD | \
 123				  CTR_FLAG_WRITE_MOSTLY | \
 124				  CTR_FLAG_DAEMON_SLEEP | \
 125				  CTR_FLAG_MIN_RECOVERY_RATE | \
 126				  CTR_FLAG_MAX_RECOVERY_RATE | \
 127				  CTR_FLAG_MAX_WRITE_BEHIND | \
 128				  CTR_FLAG_STRIPE_CACHE | \
 129				  CTR_FLAG_REGION_SIZE | \
 130				  CTR_FLAG_RAID10_COPIES | \
 131				  CTR_FLAG_RAID10_FORMAT | \
 132				  CTR_FLAG_DELTA_DISKS | \
 133				  CTR_FLAG_DATA_OFFSET | \
 134				  CTR_FLAG_JOURNAL_DEV | \
 135				  CTR_FLAG_JOURNAL_MODE)
 136
 137/* Valid options definitions per raid level... */
 138
 139/* "raid0" does only accept data offset */
 140#define RAID0_VALID_FLAGS	(CTR_FLAG_DATA_OFFSET)
 141
 142/* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */
 143#define RAID1_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 144				 CTR_FLAG_REBUILD | \
 145				 CTR_FLAG_WRITE_MOSTLY | \
 146				 CTR_FLAG_DAEMON_SLEEP | \
 147				 CTR_FLAG_MIN_RECOVERY_RATE | \
 148				 CTR_FLAG_MAX_RECOVERY_RATE | \
 149				 CTR_FLAG_MAX_WRITE_BEHIND | \
 150				 CTR_FLAG_REGION_SIZE | \
 151				 CTR_FLAG_DELTA_DISKS | \
 152				 CTR_FLAG_DATA_OFFSET)
 153
 154/* "raid10" does not accept any raid1 or stripe cache options */
 155#define RAID10_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 156				 CTR_FLAG_REBUILD | \
 157				 CTR_FLAG_DAEMON_SLEEP | \
 158				 CTR_FLAG_MIN_RECOVERY_RATE | \
 159				 CTR_FLAG_MAX_RECOVERY_RATE | \
 160				 CTR_FLAG_REGION_SIZE | \
 161				 CTR_FLAG_RAID10_COPIES | \
 162				 CTR_FLAG_RAID10_FORMAT | \
 163				 CTR_FLAG_DELTA_DISKS | \
 164				 CTR_FLAG_DATA_OFFSET | \
 165				 CTR_FLAG_RAID10_USE_NEAR_SETS)
 166
 167/*
 168 * "raid4/5/6" do not accept any raid1 or raid10 specific options
 169 *
 170 * "raid6" does not accept "nosync", because it is not guaranteed
 171 * that both parity and q-syndrome are being written properly with
 172 * any writes
 173 */
 174#define RAID45_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 175				 CTR_FLAG_REBUILD | \
 176				 CTR_FLAG_DAEMON_SLEEP | \
 177				 CTR_FLAG_MIN_RECOVERY_RATE | \
 178				 CTR_FLAG_MAX_RECOVERY_RATE | \
 179				 CTR_FLAG_STRIPE_CACHE | \
 180				 CTR_FLAG_REGION_SIZE | \
 181				 CTR_FLAG_DELTA_DISKS | \
 182				 CTR_FLAG_DATA_OFFSET | \
 183				 CTR_FLAG_JOURNAL_DEV | \
 184				 CTR_FLAG_JOURNAL_MODE)
 185
 186#define RAID6_VALID_FLAGS	(CTR_FLAG_SYNC | \
 187				 CTR_FLAG_REBUILD | \
 188				 CTR_FLAG_DAEMON_SLEEP | \
 189				 CTR_FLAG_MIN_RECOVERY_RATE | \
 190				 CTR_FLAG_MAX_RECOVERY_RATE | \
 191				 CTR_FLAG_STRIPE_CACHE | \
 192				 CTR_FLAG_REGION_SIZE | \
 193				 CTR_FLAG_DELTA_DISKS | \
 194				 CTR_FLAG_DATA_OFFSET | \
 195				 CTR_FLAG_JOURNAL_DEV | \
 196				 CTR_FLAG_JOURNAL_MODE)
 197/* ...valid options definitions per raid level */
 198
 199/*
 200 * Flags for rs->runtime_flags field
 201 * (RT_FLAG prefix meaning "runtime flag")
 202 *
 203 * These are all internal and used to define runtime state,
 204 * e.g. to prevent another resume from preresume processing
 205 * the raid set all over again.
 206 */
 207#define RT_FLAG_RS_PRERESUMED		0
 208#define RT_FLAG_RS_RESUMED		1
 209#define RT_FLAG_RS_BITMAP_LOADED	2
 210#define RT_FLAG_UPDATE_SBS		3
 211#define RT_FLAG_RESHAPE_RS		4
 212#define RT_FLAG_RS_SUSPENDED		5
 213#define RT_FLAG_RS_IN_SYNC		6
 214#define RT_FLAG_RS_RESYNCING		7
 215#define RT_FLAG_RS_GROW			8
 216#define RT_FLAG_RS_FROZEN		9
 217
 218/* Array elements of 64 bit needed for rebuild/failed disk bits */
 219#define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
 220
 221/*
 222 * raid set level, layout and chunk sectors backup/restore
 223 */
 224struct rs_layout {
 225	int new_level;
 226	int new_layout;
 227	int new_chunk_sectors;
 228};
 229
 230struct raid_set {
 231	struct dm_target *ti;
 232
 233	uint32_t stripe_cache_entries;
 234	unsigned long ctr_flags;
 235	unsigned long runtime_flags;
 236
 237	uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
 238
 239	int raid_disks;
 240	int delta_disks;
 241	int data_offset;
 242	int raid10_copies;
 243	int requested_bitmap_chunk_sectors;
 244
 245	struct mddev md;
 246	struct raid_type *raid_type;
 247
 248	sector_t array_sectors;
 249	sector_t dev_sectors;
 250
 251	/* Optional raid4/5/6 journal device */
 252	struct journal_dev {
 253		struct dm_dev *dev;
 254		struct md_rdev rdev;
 255		int mode;
 256	} journal_dev;
 257
 258	struct raid_dev dev[] __counted_by(raid_disks);
 259};
 260
 261static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)
 262{
 263	struct mddev *mddev = &rs->md;
 264
 265	l->new_level = mddev->new_level;
 266	l->new_layout = mddev->new_layout;
 267	l->new_chunk_sectors = mddev->new_chunk_sectors;
 268}
 269
 270static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)
 271{
 272	struct mddev *mddev = &rs->md;
 273
 274	mddev->new_level = l->new_level;
 275	mddev->new_layout = l->new_layout;
 276	mddev->new_chunk_sectors = l->new_chunk_sectors;
 277}
 278
 279/* raid10 algorithms (i.e. formats) */
 280#define	ALGORITHM_RAID10_DEFAULT	0
 281#define	ALGORITHM_RAID10_NEAR		1
 282#define	ALGORITHM_RAID10_OFFSET		2
 283#define	ALGORITHM_RAID10_FAR		3
 284
 285/* Supported raid types and properties. */
 286static struct raid_type {
 287	const char *name;		/* RAID algorithm. */
 288	const char *descr;		/* Descriptor text for logging. */
 289	const unsigned int parity_devs;	/* # of parity devices. */
 290	const unsigned int minimal_devs;/* minimal # of devices in set. */
 291	const unsigned int level;	/* RAID level. */
 292	const unsigned int algorithm;	/* RAID algorithm. */
 293} raid_types[] = {
 294	{"raid0",	  "raid0 (striping)",			    0, 2, 0,  0 /* NONE */},
 295	{"raid1",	  "raid1 (mirroring)",			    0, 2, 1,  0 /* NONE */},
 296	{"raid10_far",	  "raid10 far (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_FAR},
 297	{"raid10_offset", "raid10 offset (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_OFFSET},
 298	{"raid10_near",	  "raid10 near (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_NEAR},
 299	{"raid10",	  "raid10 (striped mirrors)",		    0, 2, 10, ALGORITHM_RAID10_DEFAULT},
 300	{"raid4",	  "raid4 (dedicated first parity disk)",    1, 2, 5,  ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */
 301	{"raid5_n",	  "raid5 (dedicated last parity disk)",	    1, 2, 5,  ALGORITHM_PARITY_N},
 302	{"raid5_ls",	  "raid5 (left symmetric)",		    1, 2, 5,  ALGORITHM_LEFT_SYMMETRIC},
 303	{"raid5_rs",	  "raid5 (right symmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_SYMMETRIC},
 304	{"raid5_la",	  "raid5 (left asymmetric)",		    1, 2, 5,  ALGORITHM_LEFT_ASYMMETRIC},
 305	{"raid5_ra",	  "raid5 (right asymmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_ASYMMETRIC},
 306	{"raid6_zr",	  "raid6 (zero restart)",		    2, 4, 6,  ALGORITHM_ROTATING_ZERO_RESTART},
 307	{"raid6_nr",	  "raid6 (N restart)",			    2, 4, 6,  ALGORITHM_ROTATING_N_RESTART},
 308	{"raid6_nc",	  "raid6 (N continue)",			    2, 4, 6,  ALGORITHM_ROTATING_N_CONTINUE},
 309	{"raid6_n_6",	  "raid6 (dedicated parity/Q n/6)",	    2, 4, 6,  ALGORITHM_PARITY_N_6},
 310	{"raid6_ls_6",	  "raid6 (left symmetric dedicated Q 6)",   2, 4, 6,  ALGORITHM_LEFT_SYMMETRIC_6},
 311	{"raid6_rs_6",	  "raid6 (right symmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_RIGHT_SYMMETRIC_6},
 312	{"raid6_la_6",	  "raid6 (left asymmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_LEFT_ASYMMETRIC_6},
 313	{"raid6_ra_6",	  "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6,  ALGORITHM_RIGHT_ASYMMETRIC_6}
 314};
 315
 316/* True, if @v is in inclusive range [@min, @max] */
 317static bool __within_range(long v, long min, long max)
 318{
 319	return v >= min && v <= max;
 320}
 321
 322/* All table line arguments are defined here */
 323static struct arg_name_flag {
 324	const unsigned long flag;
 325	const char *name;
 326} __arg_name_flags[] = {
 327	{ CTR_FLAG_SYNC, "sync"},
 328	{ CTR_FLAG_NOSYNC, "nosync"},
 329	{ CTR_FLAG_REBUILD, "rebuild"},
 330	{ CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
 331	{ CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
 332	{ CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
 333	{ CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
 334	{ CTR_FLAG_WRITE_MOSTLY, "write_mostly"},
 335	{ CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
 336	{ CTR_FLAG_REGION_SIZE, "region_size"},
 337	{ CTR_FLAG_RAID10_COPIES, "raid10_copies"},
 338	{ CTR_FLAG_RAID10_FORMAT, "raid10_format"},
 339	{ CTR_FLAG_DATA_OFFSET, "data_offset"},
 340	{ CTR_FLAG_DELTA_DISKS, "delta_disks"},
 341	{ CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
 342	{ CTR_FLAG_JOURNAL_DEV, "journal_dev" },
 343	{ CTR_FLAG_JOURNAL_MODE, "journal_mode" },
 344};
 345
 346/* Return argument name string for given @flag */
 347static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
 348{
 349	if (hweight32(flag) == 1) {
 350		struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
 351
 352		while (anf-- > __arg_name_flags)
 353			if (flag & anf->flag)
 354				return anf->name;
 355
 356	} else
 357		DMERR("%s called with more than one flag!", __func__);
 358
 359	return NULL;
 360}
 361
 362/* Define correlation of raid456 journal cache modes and dm-raid target line parameters */
 363static struct {
 364	const int mode;
 365	const char *param;
 366} _raid456_journal_mode[] = {
 367	{ R5C_JOURNAL_MODE_WRITE_THROUGH, "writethrough" },
 368	{ R5C_JOURNAL_MODE_WRITE_BACK,    "writeback" }
 369};
 370
 371/* Return MD raid4/5/6 journal mode for dm @journal_mode one */
 372static int dm_raid_journal_mode_to_md(const char *mode)
 373{
 374	int m = ARRAY_SIZE(_raid456_journal_mode);
 375
 376	while (m--)
 377		if (!strcasecmp(mode, _raid456_journal_mode[m].param))
 378			return _raid456_journal_mode[m].mode;
 379
 380	return -EINVAL;
 381}
 382
 383/* Return dm-raid raid4/5/6 journal mode string for @mode */
 384static const char *md_journal_mode_to_dm_raid(const int mode)
 385{
 386	int m = ARRAY_SIZE(_raid456_journal_mode);
 387
 388	while (m--)
 389		if (mode == _raid456_journal_mode[m].mode)
 390			return _raid456_journal_mode[m].param;
 391
 392	return "unknown";
 393}
 394
 395/*
 396 * Bool helpers to test for various raid levels of a raid set.
 397 * It's level as reported by the superblock rather than
 398 * the requested raid_type passed to the constructor.
 399 */
 400/* Return true, if raid set in @rs is raid0 */
 401static bool rs_is_raid0(struct raid_set *rs)
 402{
 403	return !rs->md.level;
 404}
 405
 406/* Return true, if raid set in @rs is raid1 */
 407static bool rs_is_raid1(struct raid_set *rs)
 408{
 409	return rs->md.level == 1;
 410}
 411
 412/* Return true, if raid set in @rs is raid10 */
 413static bool rs_is_raid10(struct raid_set *rs)
 414{
 415	return rs->md.level == 10;
 416}
 417
 418/* Return true, if raid set in @rs is level 6 */
 419static bool rs_is_raid6(struct raid_set *rs)
 420{
 421	return rs->md.level == 6;
 422}
 423
 424/* Return true, if raid set in @rs is level 4, 5 or 6 */
 425static bool rs_is_raid456(struct raid_set *rs)
 426{
 427	return __within_range(rs->md.level, 4, 6);
 428}
 429
 430/* Return true, if raid set in @rs is reshapable */
 431static bool __is_raid10_far(int layout);
 432static bool rs_is_reshapable(struct raid_set *rs)
 433{
 434	return rs_is_raid456(rs) ||
 435	       (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
 436}
 437
 438/* Return true, if raid set in @rs is recovering */
 439static bool rs_is_recovering(struct raid_set *rs)
 440{
 441	return rs->md.recovery_cp < rs->md.dev_sectors;
 442}
 443
 444/* Return true, if raid set in @rs is reshaping */
 445static bool rs_is_reshaping(struct raid_set *rs)
 446{
 447	return rs->md.reshape_position != MaxSector;
 448}
 449
 450/*
 451 * bool helpers to test for various raid levels of a raid type @rt
 452 */
 453
 454/* Return true, if raid type in @rt is raid0 */
 455static bool rt_is_raid0(struct raid_type *rt)
 456{
 457	return !rt->level;
 458}
 459
 460/* Return true, if raid type in @rt is raid1 */
 461static bool rt_is_raid1(struct raid_type *rt)
 462{
 463	return rt->level == 1;
 464}
 465
 466/* Return true, if raid type in @rt is raid10 */
 467static bool rt_is_raid10(struct raid_type *rt)
 468{
 469	return rt->level == 10;
 470}
 471
 472/* Return true, if raid type in @rt is raid4/5 */
 473static bool rt_is_raid45(struct raid_type *rt)
 474{
 475	return __within_range(rt->level, 4, 5);
 476}
 477
 478/* Return true, if raid type in @rt is raid6 */
 479static bool rt_is_raid6(struct raid_type *rt)
 480{
 481	return rt->level == 6;
 482}
 483
 484/* Return true, if raid type in @rt is raid4/5/6 */
 485static bool rt_is_raid456(struct raid_type *rt)
 486{
 487	return __within_range(rt->level, 4, 6);
 488}
 489/* END: raid level bools */
 490
 491/* Return valid ctr flags for the raid level of @rs */
 492static unsigned long __valid_flags(struct raid_set *rs)
 493{
 494	if (rt_is_raid0(rs->raid_type))
 495		return RAID0_VALID_FLAGS;
 496	else if (rt_is_raid1(rs->raid_type))
 497		return RAID1_VALID_FLAGS;
 498	else if (rt_is_raid10(rs->raid_type))
 499		return RAID10_VALID_FLAGS;
 500	else if (rt_is_raid45(rs->raid_type))
 501		return RAID45_VALID_FLAGS;
 502	else if (rt_is_raid6(rs->raid_type))
 503		return RAID6_VALID_FLAGS;
 504
 505	return 0;
 506}
 507
 508/*
 509 * Check for valid flags set on @rs
 510 *
 511 * Has to be called after parsing of the ctr flags!
 512 */
 513static int rs_check_for_valid_flags(struct raid_set *rs)
 514{
 515	if (rs->ctr_flags & ~__valid_flags(rs)) {
 516		rs->ti->error = "Invalid flags combination";
 517		return -EINVAL;
 518	}
 519
 520	return 0;
 521}
 522
 523/* MD raid10 bit definitions and helpers */
 524#define RAID10_OFFSET			(1 << 16) /* stripes with data copies area adjacent on devices */
 525#define RAID10_BROCKEN_USE_FAR_SETS	(1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
 526#define RAID10_USE_FAR_SETS		(1 << 18) /* Use sets instead of whole stripe rotation */
 527#define RAID10_FAR_COPIES_SHIFT		8	  /* raid10 # far copies shift (2nd byte of layout) */
 528
 529/* Return md raid10 near copies for @layout */
 530static unsigned int __raid10_near_copies(int layout)
 531{
 532	return layout & 0xFF;
 533}
 534
 535/* Return md raid10 far copies for @layout */
 536static unsigned int __raid10_far_copies(int layout)
 537{
 538	return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
 539}
 540
 541/* Return true if md raid10 offset for @layout */
 542static bool __is_raid10_offset(int layout)
 543{
 544	return !!(layout & RAID10_OFFSET);
 545}
 546
 547/* Return true if md raid10 near for @layout */
 548static bool __is_raid10_near(int layout)
 549{
 550	return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
 551}
 552
 553/* Return true if md raid10 far for @layout */
 554static bool __is_raid10_far(int layout)
 555{
 556	return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
 557}
 558
 559/* Return md raid10 layout string for @layout */
 560static const char *raid10_md_layout_to_format(int layout)
 561{
 562	/*
 563	 * Bit 16 stands for "offset"
 564	 * (i.e. adjacent stripes hold copies)
 565	 *
 566	 * Refer to MD's raid10.c for details
 567	 */
 568	if (__is_raid10_offset(layout))
 569		return "offset";
 570
 571	if (__raid10_near_copies(layout) > 1)
 572		return "near";
 573
 574	if (__raid10_far_copies(layout) > 1)
 575		return "far";
 576
 577	return "unknown";
 578}
 579
 580/* Return md raid10 algorithm for @name */
 581static int raid10_name_to_format(const char *name)
 582{
 583	if (!strcasecmp(name, "near"))
 584		return ALGORITHM_RAID10_NEAR;
 585	else if (!strcasecmp(name, "offset"))
 586		return ALGORITHM_RAID10_OFFSET;
 587	else if (!strcasecmp(name, "far"))
 588		return ALGORITHM_RAID10_FAR;
 589
 590	return -EINVAL;
 591}
 592
 593/* Return md raid10 copies for @layout */
 594static unsigned int raid10_md_layout_to_copies(int layout)
 595{
 596	return max(__raid10_near_copies(layout), __raid10_far_copies(layout));
 597}
 598
 599/* Return md raid10 format id for @format string */
 600static int raid10_format_to_md_layout(struct raid_set *rs,
 601				      unsigned int algorithm,
 602				      unsigned int copies)
 603{
 604	unsigned int n = 1, f = 1, r = 0;
 605
 606	/*
 607	 * MD resilienece flaw:
 608	 *
 609	 * enabling use_far_sets for far/offset formats causes copies
 610	 * to be colocated on the same devs together with their origins!
 611	 *
 612	 * -> disable it for now in the definition above
 613	 */
 614	if (algorithm == ALGORITHM_RAID10_DEFAULT ||
 615	    algorithm == ALGORITHM_RAID10_NEAR)
 616		n = copies;
 617
 618	else if (algorithm == ALGORITHM_RAID10_OFFSET) {
 619		f = copies;
 620		r = RAID10_OFFSET;
 621		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 622			r |= RAID10_USE_FAR_SETS;
 623
 624	} else if (algorithm == ALGORITHM_RAID10_FAR) {
 625		f = copies;
 
 626		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 627			r |= RAID10_USE_FAR_SETS;
 628
 629	} else
 630		return -EINVAL;
 631
 632	return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
 633}
 634/* END: MD raid10 bit definitions and helpers */
 635
 636/* Check for any of the raid10 algorithms */
 637static bool __got_raid10(struct raid_type *rtp, const int layout)
 638{
 639	if (rtp->level == 10) {
 640		switch (rtp->algorithm) {
 641		case ALGORITHM_RAID10_DEFAULT:
 642		case ALGORITHM_RAID10_NEAR:
 643			return __is_raid10_near(layout);
 644		case ALGORITHM_RAID10_OFFSET:
 645			return __is_raid10_offset(layout);
 646		case ALGORITHM_RAID10_FAR:
 647			return __is_raid10_far(layout);
 648		default:
 649			break;
 650		}
 651	}
 652
 653	return false;
 654}
 655
 656/* Return raid_type for @name */
 657static struct raid_type *get_raid_type(const char *name)
 658{
 659	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 660
 661	while (rtp-- > raid_types)
 662		if (!strcasecmp(rtp->name, name))
 663			return rtp;
 664
 665	return NULL;
 666}
 667
 668/* Return raid_type for @name based derived from @level and @layout */
 669static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
 670{
 671	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 672
 673	while (rtp-- > raid_types) {
 674		/* RAID10 special checks based on @layout flags/properties */
 675		if (rtp->level == level &&
 676		    (__got_raid10(rtp, layout) || rtp->algorithm == layout))
 677			return rtp;
 678	}
 679
 680	return NULL;
 681}
 682
 683/* Adjust rdev sectors */
 684static void rs_set_rdev_sectors(struct raid_set *rs)
 685{
 686	struct mddev *mddev = &rs->md;
 687	struct md_rdev *rdev;
 688
 689	/*
 690	 * raid10 sets rdev->sector to the device size, which
 691	 * is unintended in case of out-of-place reshaping
 692	 */
 693	rdev_for_each(rdev, mddev)
 694		if (!test_bit(Journal, &rdev->flags))
 695			rdev->sectors = mddev->dev_sectors;
 696}
 697
 698/*
 699 * Change bdev capacity of @rs in case of a disk add/remove reshape
 700 */
 701static void rs_set_capacity(struct raid_set *rs)
 702{
 703	struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
 704
 705	set_capacity_and_notify(gendisk, rs->md.array_sectors);
 
 706}
 707
 708/*
 709 * Set the mddev properties in @rs to the current
 710 * ones retrieved from the freshest superblock
 711 */
 712static void rs_set_cur(struct raid_set *rs)
 713{
 714	struct mddev *mddev = &rs->md;
 715
 716	mddev->new_level = mddev->level;
 717	mddev->new_layout = mddev->layout;
 718	mddev->new_chunk_sectors = mddev->chunk_sectors;
 719}
 720
 721/*
 722 * Set the mddev properties in @rs to the new
 723 * ones requested by the ctr
 724 */
 725static void rs_set_new(struct raid_set *rs)
 726{
 727	struct mddev *mddev = &rs->md;
 728
 729	mddev->level = mddev->new_level;
 730	mddev->layout = mddev->new_layout;
 731	mddev->chunk_sectors = mddev->new_chunk_sectors;
 732	mddev->raid_disks = rs->raid_disks;
 733	mddev->delta_disks = 0;
 734}
 735
 736static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
 737				       unsigned int raid_devs)
 738{
 739	unsigned int i;
 740	struct raid_set *rs;
 741
 742	if (raid_devs <= raid_type->parity_devs) {
 743		ti->error = "Insufficient number of devices";
 744		return ERR_PTR(-EINVAL);
 745	}
 746
 747	rs = kzalloc(struct_size(rs, dev, raid_devs), GFP_KERNEL);
 748	if (!rs) {
 749		ti->error = "Cannot allocate raid context";
 750		return ERR_PTR(-ENOMEM);
 751	}
 752
 753	if (mddev_init(&rs->md)) {
 754		kfree(rs);
 755		ti->error = "Cannot initialize raid context";
 756		return ERR_PTR(-ENOMEM);
 757	}
 758
 759	rs->raid_disks = raid_devs;
 760	rs->delta_disks = 0;
 761
 762	rs->ti = ti;
 763	rs->raid_type = raid_type;
 764	rs->stripe_cache_entries = 256;
 765	rs->md.raid_disks = raid_devs;
 766	rs->md.level = raid_type->level;
 767	rs->md.new_level = rs->md.level;
 768	rs->md.layout = raid_type->algorithm;
 769	rs->md.new_layout = rs->md.layout;
 770	rs->md.delta_disks = 0;
 771	rs->md.recovery_cp = MaxSector;
 772
 773	for (i = 0; i < raid_devs; i++)
 774		md_rdev_init(&rs->dev[i].rdev);
 775
 776	/*
 777	 * Remaining items to be initialized by further RAID params:
 778	 *  rs->md.persistent
 779	 *  rs->md.external
 780	 *  rs->md.chunk_sectors
 781	 *  rs->md.new_chunk_sectors
 782	 *  rs->md.dev_sectors
 783	 */
 784
 785	return rs;
 786}
 787
 788/* Free all @rs allocations */
 789static void raid_set_free(struct raid_set *rs)
 790{
 791	int i;
 792
 793	if (rs->journal_dev.dev) {
 794		md_rdev_clear(&rs->journal_dev.rdev);
 795		dm_put_device(rs->ti, rs->journal_dev.dev);
 796	}
 797
 798	for (i = 0; i < rs->raid_disks; i++) {
 799		if (rs->dev[i].meta_dev)
 800			dm_put_device(rs->ti, rs->dev[i].meta_dev);
 801		md_rdev_clear(&rs->dev[i].rdev);
 802		if (rs->dev[i].data_dev)
 803			dm_put_device(rs->ti, rs->dev[i].data_dev);
 804	}
 805
 806	mddev_destroy(&rs->md);
 807	kfree(rs);
 808}
 809
 810/*
 811 * For every device we have two words
 812 *  <meta_dev>: meta device name or '-' if missing
 813 *  <data_dev>: data device name or '-' if missing
 814 *
 815 * The following are permitted:
 816 *    - -
 817 *    - <data_dev>
 818 *    <meta_dev> <data_dev>
 819 *
 820 * The following is not allowed:
 821 *    <meta_dev> -
 822 *
 823 * This code parses those words.  If there is a failure,
 824 * the caller must use raid_set_free() to unwind the operations.
 825 */
 826static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
 827{
 828	int i;
 829	int rebuild = 0;
 830	int metadata_available = 0;
 831	int r = 0;
 832	const char *arg;
 833
 834	/* Put off the number of raid devices argument to get to dev pairs */
 835	arg = dm_shift_arg(as);
 836	if (!arg)
 837		return -EINVAL;
 838
 839	for (i = 0; i < rs->raid_disks; i++) {
 840		rs->dev[i].rdev.raid_disk = i;
 841
 842		rs->dev[i].meta_dev = NULL;
 843		rs->dev[i].data_dev = NULL;
 844
 845		/*
 846		 * There are no offsets initially.
 847		 * Out of place reshape will set them accordingly.
 848		 */
 849		rs->dev[i].rdev.data_offset = 0;
 850		rs->dev[i].rdev.new_data_offset = 0;
 851		rs->dev[i].rdev.mddev = &rs->md;
 852
 853		arg = dm_shift_arg(as);
 854		if (!arg)
 855			return -EINVAL;
 856
 857		if (strcmp(arg, "-")) {
 858			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 859					  &rs->dev[i].meta_dev);
 860			if (r) {
 861				rs->ti->error = "RAID metadata device lookup failure";
 862				return r;
 863			}
 864
 865			rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
 866			if (!rs->dev[i].rdev.sb_page) {
 867				rs->ti->error = "Failed to allocate superblock page";
 868				return -ENOMEM;
 869			}
 870		}
 871
 872		arg = dm_shift_arg(as);
 873		if (!arg)
 874			return -EINVAL;
 875
 876		if (!strcmp(arg, "-")) {
 877			if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
 878			    (!rs->dev[i].rdev.recovery_offset)) {
 879				rs->ti->error = "Drive designated for rebuild not specified";
 880				return -EINVAL;
 881			}
 882
 883			if (rs->dev[i].meta_dev) {
 884				rs->ti->error = "No data device supplied with metadata device";
 885				return -EINVAL;
 886			}
 887
 888			continue;
 889		}
 890
 891		r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 892				  &rs->dev[i].data_dev);
 893		if (r) {
 894			rs->ti->error = "RAID device lookup failure";
 895			return r;
 896		}
 897
 898		if (rs->dev[i].meta_dev) {
 899			metadata_available = 1;
 900			rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
 901		}
 902		rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
 903		list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
 904		if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
 905			rebuild++;
 906	}
 907
 908	if (rs->journal_dev.dev)
 909		list_add_tail(&rs->journal_dev.rdev.same_set, &rs->md.disks);
 910
 911	if (metadata_available) {
 912		rs->md.external = 0;
 913		rs->md.persistent = 1;
 914		rs->md.major_version = 2;
 915	} else if (rebuild && !rs->md.recovery_cp) {
 916		/*
 917		 * Without metadata, we will not be able to tell if the array
 918		 * is in-sync or not - we must assume it is not.  Therefore,
 919		 * it is impossible to rebuild a drive.
 920		 *
 921		 * Even if there is metadata, the on-disk information may
 922		 * indicate that the array is not in-sync and it will then
 923		 * fail at that time.
 924		 *
 925		 * User could specify 'nosync' option if desperate.
 926		 */
 927		rs->ti->error = "Unable to rebuild drive while array is not in-sync";
 928		return -EINVAL;
 929	}
 930
 931	return 0;
 932}
 933
 934/*
 935 * validate_region_size
 936 * @rs
 937 * @region_size:  region size in sectors.  If 0, pick a size (4MiB default).
 938 *
 939 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
 940 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
 941 *
 942 * Returns: 0 on success, -EINVAL on failure.
 943 */
 944static int validate_region_size(struct raid_set *rs, unsigned long region_size)
 945{
 946	unsigned long min_region_size = rs->ti->len / (1 << 21);
 947
 948	if (rs_is_raid0(rs))
 949		return 0;
 950
 951	if (!region_size) {
 952		/*
 953		 * Choose a reasonable default.	 All figures in sectors.
 954		 */
 955		if (min_region_size > (1 << 13)) {
 956			/* If not a power of 2, make it the next power of 2 */
 957			region_size = roundup_pow_of_two(min_region_size);
 958			DMINFO("Choosing default region size of %lu sectors",
 959			       region_size);
 960		} else {
 961			DMINFO("Choosing default region size of 4MiB");
 962			region_size = 1 << 13; /* sectors */
 963		}
 964	} else {
 965		/*
 966		 * Validate user-supplied value.
 967		 */
 968		if (region_size > rs->ti->len) {
 969			rs->ti->error = "Supplied region size is too large";
 970			return -EINVAL;
 971		}
 972
 973		if (region_size < min_region_size) {
 974			DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
 975			      region_size, min_region_size);
 976			rs->ti->error = "Supplied region size is too small";
 977			return -EINVAL;
 978		}
 979
 980		if (!is_power_of_2(region_size)) {
 981			rs->ti->error = "Region size is not a power of 2";
 982			return -EINVAL;
 983		}
 984
 985		if (region_size < rs->md.chunk_sectors) {
 986			rs->ti->error = "Region size is smaller than the chunk size";
 987			return -EINVAL;
 988		}
 989	}
 990
 991	/*
 992	 * Convert sectors to bytes.
 993	 */
 994	rs->md.bitmap_info.chunksize = to_bytes(region_size);
 995
 996	return 0;
 997}
 998
 999/*
1000 * validate_raid_redundancy
1001 * @rs
1002 *
1003 * Determine if there are enough devices in the array that haven't
1004 * failed (or are being rebuilt) to form a usable array.
1005 *
1006 * Returns: 0 on success, -EINVAL on failure.
1007 */
1008static int validate_raid_redundancy(struct raid_set *rs)
1009{
1010	unsigned int i, rebuild_cnt = 0;
1011	unsigned int rebuilds_per_group = 0, copies, raid_disks;
1012	unsigned int group_size, last_group_start;
1013
1014	for (i = 0; i < rs->raid_disks; i++)
1015		if (!test_bit(FirstUse, &rs->dev[i].rdev.flags) &&
1016		    ((!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
1017		      !rs->dev[i].rdev.sb_page)))
1018			rebuild_cnt++;
1019
1020	switch (rs->md.level) {
1021	case 0:
1022		break;
1023	case 1:
1024		if (rebuild_cnt >= rs->md.raid_disks)
1025			goto too_many;
1026		break;
1027	case 4:
1028	case 5:
1029	case 6:
1030		if (rebuild_cnt > rs->raid_type->parity_devs)
1031			goto too_many;
1032		break;
1033	case 10:
1034		copies = raid10_md_layout_to_copies(rs->md.new_layout);
1035		if (copies < 2) {
1036			DMERR("Bogus raid10 data copies < 2!");
1037			return -EINVAL;
1038		}
1039
1040		if (rebuild_cnt < copies)
1041			break;
1042
1043		/*
1044		 * It is possible to have a higher rebuild count for RAID10,
1045		 * as long as the failed devices occur in different mirror
1046		 * groups (i.e. different stripes).
1047		 *
1048		 * When checking "near" format, make sure no adjacent devices
1049		 * have failed beyond what can be handled.  In addition to the
1050		 * simple case where the number of devices is a multiple of the
1051		 * number of copies, we must also handle cases where the number
1052		 * of devices is not a multiple of the number of copies.
1053		 * E.g.	   dev1 dev2 dev3 dev4 dev5
1054		 *	    A	 A    B	   B	C
1055		 *	    C	 D    D	   E	E
1056		 */
1057		raid_disks = min(rs->raid_disks, rs->md.raid_disks);
1058		if (__is_raid10_near(rs->md.new_layout)) {
1059			for (i = 0; i < raid_disks; i++) {
1060				if (!(i % copies))
1061					rebuilds_per_group = 0;
1062				if ((!rs->dev[i].rdev.sb_page ||
1063				    !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1064				    (++rebuilds_per_group >= copies))
1065					goto too_many;
1066			}
1067			break;
1068		}
1069
1070		/*
1071		 * When checking "far" and "offset" formats, we need to ensure
1072		 * that the device that holds its copy is not also dead or
1073		 * being rebuilt.  (Note that "far" and "offset" formats only
1074		 * support two copies right now.  These formats also only ever
1075		 * use the 'use_far_sets' variant.)
1076		 *
1077		 * This check is somewhat complicated by the need to account
1078		 * for arrays that are not a multiple of (far) copies.	This
1079		 * results in the need to treat the last (potentially larger)
1080		 * set differently.
1081		 */
1082		group_size = (raid_disks / copies);
1083		last_group_start = (raid_disks / group_size) - 1;
1084		last_group_start *= group_size;
1085		for (i = 0; i < raid_disks; i++) {
1086			if (!(i % copies) && !(i > last_group_start))
1087				rebuilds_per_group = 0;
1088			if ((!rs->dev[i].rdev.sb_page ||
1089			     !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1090			    (++rebuilds_per_group >= copies))
1091				goto too_many;
1092		}
1093		break;
1094	default:
1095		if (rebuild_cnt)
1096			return -EINVAL;
1097	}
1098
1099	return 0;
1100
1101too_many:
1102	return -EINVAL;
1103}
1104
1105/*
1106 * Possible arguments are...
1107 *	<chunk_size> [optional_args]
1108 *
1109 * Argument definitions
1110 *    <chunk_size>			The number of sectors per disk that
1111 *					will form the "stripe"
1112 *    [[no]sync]			Force or prevent recovery of the
1113 *					entire array
1114 *    [rebuild <idx>]			Rebuild the drive indicated by the index
1115 *    [daemon_sleep <ms>]		Time between bitmap daemon work to
1116 *					clear bits
1117 *    [min_recovery_rate <kB/sec/disk>]	Throttle RAID initialization
1118 *    [max_recovery_rate <kB/sec/disk>]	Throttle RAID initialization
1119 *    [write_mostly <idx>]		Indicate a write mostly drive via index
1120 *    [max_write_behind <sectors>]	See '-write-behind=' (man mdadm)
1121 *    [stripe_cache <sectors>]		Stripe cache size for higher RAIDs
1122 *    [region_size <sectors>]		Defines granularity of bitmap
1123 *    [journal_dev <dev>]		raid4/5/6 journaling deviice
1124 *					(i.e. write hole closing log)
1125 *
1126 * RAID10-only options:
1127 *    [raid10_copies <# copies>]	Number of copies.  (Default: 2)
1128 *    [raid10_format <near|far|offset>] Layout algorithm.  (Default: near)
1129 */
1130static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
1131			     unsigned int num_raid_params)
1132{
1133	int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
1134	unsigned int raid10_copies = 2;
1135	unsigned int i, write_mostly = 0;
1136	unsigned int region_size = 0;
1137	sector_t max_io_len;
1138	const char *arg, *key;
1139	struct raid_dev *rd;
1140	struct raid_type *rt = rs->raid_type;
1141
1142	arg = dm_shift_arg(as);
1143	num_raid_params--; /* Account for chunk_size argument */
1144
1145	if (kstrtoint(arg, 10, &value) < 0) {
1146		rs->ti->error = "Bad numerical argument given for chunk_size";
1147		return -EINVAL;
1148	}
1149
1150	/*
1151	 * First, parse the in-order required arguments
1152	 * "chunk_size" is the only argument of this type.
1153	 */
1154	if (rt_is_raid1(rt)) {
1155		if (value)
1156			DMERR("Ignoring chunk size parameter for RAID 1");
1157		value = 0;
1158	} else if (!is_power_of_2(value)) {
1159		rs->ti->error = "Chunk size must be a power of 2";
1160		return -EINVAL;
1161	} else if (value < 8) {
1162		rs->ti->error = "Chunk size value is too small";
1163		return -EINVAL;
1164	}
1165
1166	rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1167
1168	/*
1169	 * We set each individual device as In_sync with a completed
1170	 * 'recovery_offset'.  If there has been a device failure or
1171	 * replacement then one of the following cases applies:
1172	 *
1173	 *   1) User specifies 'rebuild'.
1174	 *	- Device is reset when param is read.
1175	 *   2) A new device is supplied.
1176	 *	- No matching superblock found, resets device.
1177	 *   3) Device failure was transient and returns on reload.
1178	 *	- Failure noticed, resets device for bitmap replay.
1179	 *   4) Device hadn't completed recovery after previous failure.
1180	 *	- Superblock is read and overrides recovery_offset.
1181	 *
1182	 * What is found in the superblocks of the devices is always
1183	 * authoritative, unless 'rebuild' or '[no]sync' was specified.
1184	 */
1185	for (i = 0; i < rs->raid_disks; i++) {
1186		set_bit(In_sync, &rs->dev[i].rdev.flags);
1187		rs->dev[i].rdev.recovery_offset = MaxSector;
1188	}
1189
1190	/*
1191	 * Second, parse the unordered optional arguments
1192	 */
1193	for (i = 0; i < num_raid_params; i++) {
1194		key = dm_shift_arg(as);
1195		if (!key) {
1196			rs->ti->error = "Not enough raid parameters given";
1197			return -EINVAL;
1198		}
1199
1200		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1201			if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1202				rs->ti->error = "Only one 'nosync' argument allowed";
1203				return -EINVAL;
1204			}
1205			continue;
1206		}
1207		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1208			if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1209				rs->ti->error = "Only one 'sync' argument allowed";
1210				return -EINVAL;
1211			}
1212			continue;
1213		}
1214		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1215			if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1216				rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1217				return -EINVAL;
1218			}
1219			continue;
1220		}
1221
1222		arg = dm_shift_arg(as);
1223		i++; /* Account for the argument pairs */
1224		if (!arg) {
1225			rs->ti->error = "Wrong number of raid parameters given";
1226			return -EINVAL;
1227		}
1228
1229		/*
1230		 * Parameters that take a string value are checked here.
1231		 */
1232		/* "raid10_format {near|offset|far} */
1233		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1234			if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1235				rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1236				return -EINVAL;
1237			}
1238			if (!rt_is_raid10(rt)) {
1239				rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1240				return -EINVAL;
1241			}
1242			raid10_format = raid10_name_to_format(arg);
1243			if (raid10_format < 0) {
1244				rs->ti->error = "Invalid 'raid10_format' value given";
1245				return raid10_format;
1246			}
1247			continue;
1248		}
1249
1250		/* "journal_dev <dev>" */
1251		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV))) {
1252			int r;
1253			struct md_rdev *jdev;
1254
1255			if (test_and_set_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
1256				rs->ti->error = "Only one raid4/5/6 set journaling device allowed";
1257				return -EINVAL;
1258			}
1259			if (!rt_is_raid456(rt)) {
1260				rs->ti->error = "'journal_dev' is an invalid parameter for this RAID type";
1261				return -EINVAL;
1262			}
1263			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
1264					  &rs->journal_dev.dev);
1265			if (r) {
1266				rs->ti->error = "raid4/5/6 journal device lookup failure";
1267				return r;
1268			}
1269			jdev = &rs->journal_dev.rdev;
1270			md_rdev_init(jdev);
1271			jdev->mddev = &rs->md;
1272			jdev->bdev = rs->journal_dev.dev->bdev;
1273			jdev->sectors = bdev_nr_sectors(jdev->bdev);
1274			if (jdev->sectors < MIN_RAID456_JOURNAL_SPACE) {
1275				rs->ti->error = "No space for raid4/5/6 journal";
1276				return -ENOSPC;
1277			}
1278			rs->journal_dev.mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
1279			set_bit(Journal, &jdev->flags);
1280			continue;
1281		}
1282
1283		/* "journal_mode <mode>" ("journal_dev" mandatory!) */
1284		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE))) {
1285			int r;
1286
1287			if (!test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
1288				rs->ti->error = "raid4/5/6 'journal_mode' is invalid without 'journal_dev'";
1289				return -EINVAL;
1290			}
1291			if (test_and_set_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
1292				rs->ti->error = "Only one raid4/5/6 'journal_mode' argument allowed";
1293				return -EINVAL;
1294			}
1295			r = dm_raid_journal_mode_to_md(arg);
1296			if (r < 0) {
1297				rs->ti->error = "Invalid 'journal_mode' argument";
1298				return r;
1299			}
1300			rs->journal_dev.mode = r;
1301			continue;
1302		}
1303
1304		/*
1305		 * Parameters with number values from here on.
1306		 */
1307		if (kstrtoint(arg, 10, &value) < 0) {
1308			rs->ti->error = "Bad numerical argument given in raid params";
1309			return -EINVAL;
1310		}
1311
1312		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1313			/*
1314			 * "rebuild" is being passed in by userspace to provide
1315			 * indexes of replaced devices and to set up additional
1316			 * devices on raid level takeover.
1317			 */
1318			if (!__within_range(value, 0, rs->raid_disks - 1)) {
1319				rs->ti->error = "Invalid rebuild index given";
1320				return -EINVAL;
1321			}
1322
1323			if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1324				rs->ti->error = "rebuild for this index already given";
1325				return -EINVAL;
1326			}
1327
1328			rd = rs->dev + value;
1329			clear_bit(In_sync, &rd->rdev.flags);
1330			clear_bit(Faulty, &rd->rdev.flags);
1331			rd->rdev.recovery_offset = 0;
1332			set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1333		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1334			if (!rt_is_raid1(rt)) {
1335				rs->ti->error = "write_mostly option is only valid for RAID1";
1336				return -EINVAL;
1337			}
1338
1339			if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1340				rs->ti->error = "Invalid write_mostly index given";
1341				return -EINVAL;
1342			}
1343
1344			write_mostly++;
1345			set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1346			set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1347		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1348			if (!rt_is_raid1(rt)) {
1349				rs->ti->error = "max_write_behind option is only valid for RAID1";
1350				return -EINVAL;
1351			}
1352
1353			if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1354				rs->ti->error = "Only one max_write_behind argument pair allowed";
1355				return -EINVAL;
1356			}
1357
1358			/*
1359			 * In device-mapper, we specify things in sectors, but
1360			 * MD records this value in kB
1361			 */
1362			if (value < 0 || value / 2 > COUNTER_MAX) {
1363				rs->ti->error = "Max write-behind limit out of range";
1364				return -EINVAL;
1365			}
1366
1367			rs->md.bitmap_info.max_write_behind = value / 2;
1368		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1369			if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1370				rs->ti->error = "Only one daemon_sleep argument pair allowed";
1371				return -EINVAL;
1372			}
1373			if (value < 0) {
1374				rs->ti->error = "daemon sleep period out of range";
1375				return -EINVAL;
1376			}
1377			rs->md.bitmap_info.daemon_sleep = value;
1378		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1379			/* Userspace passes new data_offset after having extended the data image LV */
1380			if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1381				rs->ti->error = "Only one data_offset argument pair allowed";
1382				return -EINVAL;
1383			}
1384			/* Ensure sensible data offset */
1385			if (value < 0 ||
1386			    (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {
1387				rs->ti->error = "Bogus data_offset value";
1388				return -EINVAL;
1389			}
1390			rs->data_offset = value;
1391		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1392			/* Define the +/-# of disks to add to/remove from the given raid set */
1393			if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1394				rs->ti->error = "Only one delta_disks argument pair allowed";
1395				return -EINVAL;
1396			}
1397			/* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1398			if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1399				rs->ti->error = "Too many delta_disk requested";
1400				return -EINVAL;
1401			}
1402
1403			rs->delta_disks = value;
1404		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1405			if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1406				rs->ti->error = "Only one stripe_cache argument pair allowed";
1407				return -EINVAL;
1408			}
1409
1410			if (!rt_is_raid456(rt)) {
1411				rs->ti->error = "Inappropriate argument: stripe_cache";
1412				return -EINVAL;
1413			}
1414
1415			if (value < 0) {
1416				rs->ti->error = "Bogus stripe cache entries value";
1417				return -EINVAL;
1418			}
1419			rs->stripe_cache_entries = value;
1420		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1421			if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1422				rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1423				return -EINVAL;
1424			}
1425
1426			if (value < 0) {
1427				rs->ti->error = "min_recovery_rate out of range";
1428				return -EINVAL;
1429			}
1430			rs->md.sync_speed_min = value;
1431		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1432			if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
1433				rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1434				return -EINVAL;
1435			}
1436
1437			if (value < 0) {
1438				rs->ti->error = "max_recovery_rate out of range";
1439				return -EINVAL;
1440			}
1441			rs->md.sync_speed_max = value;
1442		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1443			if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1444				rs->ti->error = "Only one region_size argument pair allowed";
1445				return -EINVAL;
1446			}
1447
1448			region_size = value;
1449			rs->requested_bitmap_chunk_sectors = value;
1450		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1451			if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1452				rs->ti->error = "Only one raid10_copies argument pair allowed";
1453				return -EINVAL;
1454			}
1455
1456			if (!__within_range(value, 2, rs->md.raid_disks)) {
1457				rs->ti->error = "Bad value for 'raid10_copies'";
1458				return -EINVAL;
1459			}
1460
1461			raid10_copies = value;
1462		} else {
1463			DMERR("Unable to parse RAID parameter: %s", key);
1464			rs->ti->error = "Unable to parse RAID parameter";
1465			return -EINVAL;
1466		}
1467	}
1468
1469	if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1470	    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1471		rs->ti->error = "sync and nosync are mutually exclusive";
1472		return -EINVAL;
1473	}
1474
1475	if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
1476	    (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
1477	     test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
1478		rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
1479		return -EINVAL;
1480	}
1481
1482	if (write_mostly >= rs->md.raid_disks) {
1483		rs->ti->error = "Can't set all raid1 devices to write_mostly";
1484		return -EINVAL;
1485	}
1486
1487	if (rs->md.sync_speed_max &&
1488	    rs->md.sync_speed_min > rs->md.sync_speed_max) {
1489		rs->ti->error = "Bogus recovery rates";
1490		return -EINVAL;
1491	}
1492
1493	if (validate_region_size(rs, region_size))
1494		return -EINVAL;
1495
1496	if (rs->md.chunk_sectors)
1497		max_io_len = rs->md.chunk_sectors;
1498	else
1499		max_io_len = region_size;
1500
1501	if (dm_set_target_max_io_len(rs->ti, max_io_len))
1502		return -EINVAL;
1503
1504	if (rt_is_raid10(rt)) {
1505		if (raid10_copies > rs->md.raid_disks) {
1506			rs->ti->error = "Not enough devices to satisfy specification";
1507			return -EINVAL;
1508		}
1509
1510		rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1511		if (rs->md.new_layout < 0) {
1512			rs->ti->error = "Error getting raid10 format";
1513			return rs->md.new_layout;
1514		}
1515
1516		rt = get_raid_type_by_ll(10, rs->md.new_layout);
1517		if (!rt) {
1518			rs->ti->error = "Failed to recognize new raid10 layout";
1519			return -EINVAL;
1520		}
1521
1522		if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1523		     rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1524		    test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1525			rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1526			return -EINVAL;
1527		}
1528	}
1529
1530	rs->raid10_copies = raid10_copies;
1531
1532	/* Assume there are no metadata devices until the drives are parsed */
1533	rs->md.persistent = 0;
1534	rs->md.external = 1;
1535
1536	/* Check, if any invalid ctr arguments have been passed in for the raid level */
1537	return rs_check_for_valid_flags(rs);
1538}
1539
1540/* Set raid4/5/6 cache size */
1541static int rs_set_raid456_stripe_cache(struct raid_set *rs)
1542{
1543	int r;
1544	struct r5conf *conf;
1545	struct mddev *mddev = &rs->md;
1546	uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
1547	uint32_t nr_stripes = rs->stripe_cache_entries;
1548
1549	if (!rt_is_raid456(rs->raid_type)) {
1550		rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
1551		return -EINVAL;
1552	}
1553
1554	if (nr_stripes < min_stripes) {
1555		DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
1556		       nr_stripes, min_stripes);
1557		nr_stripes = min_stripes;
1558	}
1559
1560	conf = mddev->private;
1561	if (!conf) {
1562		rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
1563		return -EINVAL;
1564	}
1565
1566	/* Try setting number of stripes in raid456 stripe cache */
1567	if (conf->min_nr_stripes != nr_stripes) {
1568		r = raid5_set_cache_size(mddev, nr_stripes);
1569		if (r) {
1570			rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
1571			return r;
1572		}
1573
1574		DMINFO("%u stripe cache entries", nr_stripes);
1575	}
1576
1577	return 0;
1578}
1579
1580/* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1581static unsigned int mddev_data_stripes(struct raid_set *rs)
1582{
1583	return rs->md.raid_disks - rs->raid_type->parity_devs;
1584}
1585
1586/* Return # of data stripes of @rs (i.e. as of ctr) */
1587static unsigned int rs_data_stripes(struct raid_set *rs)
1588{
1589	return rs->raid_disks - rs->raid_type->parity_devs;
1590}
1591
1592/*
1593 * Retrieve rdev->sectors from any valid raid device of @rs
1594 * to allow userpace to pass in arbitray "- -" device tupples.
1595 */
1596static sector_t __rdev_sectors(struct raid_set *rs)
1597{
1598	int i;
1599
1600	for (i = 0; i < rs->raid_disks; i++) {
1601		struct md_rdev *rdev = &rs->dev[i].rdev;
1602
1603		if (!test_bit(Journal, &rdev->flags) &&
1604		    rdev->bdev && rdev->sectors)
1605			return rdev->sectors;
1606	}
1607
1608	return 0;
1609}
1610
1611/* Check that calculated dev_sectors fits all component devices. */
1612static int _check_data_dev_sectors(struct raid_set *rs)
1613{
1614	sector_t ds = ~0;
1615	struct md_rdev *rdev;
1616
1617	rdev_for_each(rdev, &rs->md)
1618		if (!test_bit(Journal, &rdev->flags) && rdev->bdev) {
1619			ds = min(ds, bdev_nr_sectors(rdev->bdev));
1620			if (ds < rs->md.dev_sectors) {
1621				rs->ti->error = "Component device(s) too small";
1622				return -EINVAL;
1623			}
1624		}
1625
1626	return 0;
1627}
1628
1629/* Get reshape sectors from data_offsets or raid set */
1630static sector_t _get_reshape_sectors(struct raid_set *rs)
1631{
1632	struct md_rdev *rdev;
1633	sector_t reshape_sectors = 0;
1634
1635	rdev_for_each(rdev, &rs->md)
1636		if (!test_bit(Journal, &rdev->flags)) {
1637			reshape_sectors = (rdev->data_offset > rdev->new_data_offset) ?
1638					rdev->data_offset - rdev->new_data_offset :
1639					rdev->new_data_offset - rdev->data_offset;
1640			break;
1641		}
1642
1643	return max(reshape_sectors, (sector_t) rs->data_offset);
1644}
1645
1646/* Calculate the sectors per device and per array used for @rs */
1647static int rs_set_dev_and_array_sectors(struct raid_set *rs, sector_t sectors, bool use_mddev)
1648{
1649	int delta_disks;
1650	unsigned int data_stripes;
1651	sector_t array_sectors = sectors, dev_sectors = sectors;
1652	struct mddev *mddev = &rs->md;
 
 
1653
1654	if (use_mddev) {
1655		delta_disks = mddev->delta_disks;
1656		data_stripes = mddev_data_stripes(rs);
1657	} else {
1658		delta_disks = rs->delta_disks;
1659		data_stripes = rs_data_stripes(rs);
1660	}
1661
1662	/* Special raid1 case w/o delta_disks support (yet) */
1663	if (rt_is_raid1(rs->raid_type))
1664		;
1665	else if (rt_is_raid10(rs->raid_type)) {
1666		if (rs->raid10_copies < 2 ||
1667		    delta_disks < 0) {
1668			rs->ti->error = "Bogus raid10 data copies or delta disks";
1669			return -EINVAL;
1670		}
1671
1672		dev_sectors *= rs->raid10_copies;
1673		if (sector_div(dev_sectors, data_stripes))
1674			goto bad;
1675
1676		array_sectors = (data_stripes + delta_disks) * (dev_sectors - _get_reshape_sectors(rs));
1677		if (sector_div(array_sectors, rs->raid10_copies))
1678			goto bad;
1679
1680	} else if (sector_div(dev_sectors, data_stripes))
1681		goto bad;
1682
1683	else
1684		/* Striped layouts */
1685		array_sectors = (data_stripes + delta_disks) * (dev_sectors - _get_reshape_sectors(rs));
 
 
 
 
1686
1687	mddev->array_sectors = array_sectors;
1688	mddev->dev_sectors = dev_sectors;
1689	rs_set_rdev_sectors(rs);
1690
1691	return _check_data_dev_sectors(rs);
1692bad:
1693	rs->ti->error = "Target length not divisible by number of data devices";
1694	return -EINVAL;
1695}
1696
1697/* Setup recovery on @rs */
1698static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1699{
1700	/* raid0 does not recover */
1701	if (rs_is_raid0(rs))
1702		rs->md.recovery_cp = MaxSector;
1703	/*
1704	 * A raid6 set has to be recovered either
1705	 * completely or for the grown part to
1706	 * ensure proper parity and Q-Syndrome
1707	 */
1708	else if (rs_is_raid6(rs))
1709		rs->md.recovery_cp = dev_sectors;
1710	/*
1711	 * Other raid set types may skip recovery
1712	 * depending on the 'nosync' flag.
1713	 */
1714	else
1715		rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
1716				     ? MaxSector : dev_sectors;
1717}
1718
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1719static void do_table_event(struct work_struct *ws)
1720{
1721	struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1722
1723	smp_rmb(); /* Make sure we access most actual mddev properties */
1724
1725	/* Only grow size resulting from added stripe(s) after reshape ended. */
1726	if (!rs_is_reshaping(rs) &&
1727	    rs->array_sectors > rs->md.array_sectors &&
1728	    !rs->md.delta_disks &&
1729	    rs->md.raid_disks == rs->raid_disks) {
1730		/* The raid10 personality doesn't provide proper device sizes -> correct. */
1731		if (rs_is_raid10(rs))
1732			rs_set_rdev_sectors(rs);
1733
1734		rs->md.array_sectors = rs->array_sectors;
1735		rs_set_capacity(rs);
1736	}
 
 
 
 
 
 
1737
1738	dm_table_event(rs->ti->table);
1739}
1740
1741/*
1742 * Make sure a valid takover (level switch) is being requested on @rs
1743 *
1744 * Conversions of raid sets from one MD personality to another
1745 * have to conform to restrictions which are enforced here.
1746 */
1747static int rs_check_takeover(struct raid_set *rs)
1748{
1749	struct mddev *mddev = &rs->md;
1750	unsigned int near_copies;
1751
1752	if (rs->md.degraded) {
1753		rs->ti->error = "Can't takeover degraded raid set";
1754		return -EPERM;
1755	}
1756
1757	if (rs_is_reshaping(rs)) {
1758		rs->ti->error = "Can't takeover reshaping raid set";
1759		return -EPERM;
1760	}
1761
1762	switch (mddev->level) {
1763	case 0:
1764		/* raid0 -> raid1/5 with one disk */
1765		if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1766		    mddev->raid_disks == 1)
1767			return 0;
1768
1769		/* raid0 -> raid10 */
1770		if (mddev->new_level == 10 &&
1771		    !(rs->raid_disks % mddev->raid_disks))
1772			return 0;
1773
1774		/* raid0 with multiple disks -> raid4/5/6 */
1775		if (__within_range(mddev->new_level, 4, 6) &&
1776		    mddev->new_layout == ALGORITHM_PARITY_N &&
1777		    mddev->raid_disks > 1)
1778			return 0;
1779
1780		break;
1781
1782	case 10:
1783		/* Can't takeover raid10_offset! */
1784		if (__is_raid10_offset(mddev->layout))
1785			break;
1786
1787		near_copies = __raid10_near_copies(mddev->layout);
1788
1789		/* raid10* -> raid0 */
1790		if (mddev->new_level == 0) {
1791			/* Can takeover raid10_near with raid disks divisable by data copies! */
1792			if (near_copies > 1 &&
1793			    !(mddev->raid_disks % near_copies)) {
1794				mddev->raid_disks /= near_copies;
1795				mddev->delta_disks = mddev->raid_disks;
1796				return 0;
1797			}
1798
1799			/* Can takeover raid10_far */
1800			if (near_copies == 1 &&
1801			    __raid10_far_copies(mddev->layout) > 1)
1802				return 0;
1803
1804			break;
1805		}
1806
1807		/* raid10_{near,far} -> raid1 */
1808		if (mddev->new_level == 1 &&
1809		    max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1810			return 0;
1811
1812		/* raid10_{near,far} with 2 disks -> raid4/5 */
1813		if (__within_range(mddev->new_level, 4, 5) &&
1814		    mddev->raid_disks == 2)
1815			return 0;
1816		break;
1817
1818	case 1:
1819		/* raid1 with 2 disks -> raid4/5 */
1820		if (__within_range(mddev->new_level, 4, 5) &&
1821		    mddev->raid_disks == 2) {
1822			mddev->degraded = 1;
1823			return 0;
1824		}
1825
1826		/* raid1 -> raid0 */
1827		if (mddev->new_level == 0 &&
1828		    mddev->raid_disks == 1)
1829			return 0;
1830
1831		/* raid1 -> raid10 */
1832		if (mddev->new_level == 10)
1833			return 0;
1834		break;
1835
1836	case 4:
1837		/* raid4 -> raid0 */
1838		if (mddev->new_level == 0)
1839			return 0;
1840
1841		/* raid4 -> raid1/5 with 2 disks */
1842		if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1843		    mddev->raid_disks == 2)
1844			return 0;
1845
1846		/* raid4 -> raid5/6 with parity N */
1847		if (__within_range(mddev->new_level, 5, 6) &&
1848		    mddev->layout == ALGORITHM_PARITY_N)
1849			return 0;
1850		break;
1851
1852	case 5:
1853		/* raid5 with parity N -> raid0 */
1854		if (mddev->new_level == 0 &&
1855		    mddev->layout == ALGORITHM_PARITY_N)
1856			return 0;
1857
1858		/* raid5 with parity N -> raid4 */
1859		if (mddev->new_level == 4 &&
1860		    mddev->layout == ALGORITHM_PARITY_N)
1861			return 0;
1862
1863		/* raid5 with 2 disks -> raid1/4/10 */
1864		if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1865		    mddev->raid_disks == 2)
1866			return 0;
1867
1868		/* raid5_* ->  raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
1869		if (mddev->new_level == 6 &&
1870		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1871		      __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1872			return 0;
1873		break;
1874
1875	case 6:
1876		/* raid6 with parity N -> raid0 */
1877		if (mddev->new_level == 0 &&
1878		    mddev->layout == ALGORITHM_PARITY_N)
1879			return 0;
1880
1881		/* raid6 with parity N -> raid4 */
1882		if (mddev->new_level == 4 &&
1883		    mddev->layout == ALGORITHM_PARITY_N)
1884			return 0;
1885
1886		/* raid6_*_n with Q-Syndrome N -> raid5_* */
1887		if (mddev->new_level == 5 &&
1888		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1889		     __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1890			return 0;
1891		break;
1892
1893	default:
1894		break;
1895	}
1896
1897	rs->ti->error = "takeover not possible";
1898	return -EINVAL;
1899}
1900
1901/* True if @rs requested to be taken over */
1902static bool rs_takeover_requested(struct raid_set *rs)
1903{
1904	return rs->md.new_level != rs->md.level;
1905}
1906
1907/* True if layout is set to reshape. */
1908static bool rs_is_layout_change(struct raid_set *rs, bool use_mddev)
1909{
1910	return (use_mddev ? rs->md.delta_disks : rs->delta_disks) ||
1911	       rs->md.new_layout != rs->md.layout ||
1912	       rs->md.new_chunk_sectors != rs->md.chunk_sectors;
1913}
1914
1915/* True if @rs is requested to reshape by ctr */
1916static bool rs_reshape_requested(struct raid_set *rs)
1917{
1918	bool change;
1919	struct mddev *mddev = &rs->md;
1920
1921	if (rs_takeover_requested(rs))
1922		return false;
1923
1924	if (rs_is_raid0(rs))
1925		return false;
1926
1927	change = rs_is_layout_change(rs, false);
 
 
1928
1929	/* Historical case to support raid1 reshape without delta disks */
1930	if (rs_is_raid1(rs)) {
1931		if (rs->delta_disks)
1932			return !!rs->delta_disks;
1933
1934		return !change &&
1935		       mddev->raid_disks != rs->raid_disks;
1936	}
1937
1938	if (rs_is_raid10(rs))
1939		return change &&
1940		       !__is_raid10_far(mddev->new_layout) &&
1941		       rs->delta_disks >= 0;
1942
1943	return change;
1944}
1945
1946/*  Features */
1947#define	FEATURE_FLAG_SUPPORTS_V190	0x1 /* Supports extended superblock */
1948
1949/* State flags for sb->flags */
1950#define	SB_FLAG_RESHAPE_ACTIVE		0x1
1951#define	SB_FLAG_RESHAPE_BACKWARDS	0x2
1952
1953/*
1954 * This structure is never routinely used by userspace, unlike md superblocks.
1955 * Devices with this superblock should only ever be accessed via device-mapper.
1956 */
1957#define DM_RAID_MAGIC 0x64526D44
1958struct dm_raid_superblock {
1959	__le32 magic;		/* "DmRd" */
1960	__le32 compat_features;	/* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1961
1962	__le32 num_devices;	/* Number of devices in this raid set. (Max 64) */
1963	__le32 array_position;	/* The position of this drive in the raid set */
1964
1965	__le64 events;		/* Incremented by md when superblock updated */
1966	__le64 failed_devices;	/* Pre 1.9.0 part of bit field of devices to */
1967				/* indicate failures (see extension below) */
1968
1969	/*
1970	 * This offset tracks the progress of the repair or replacement of
1971	 * an individual drive.
1972	 */
1973	__le64 disk_recovery_offset;
1974
1975	/*
1976	 * This offset tracks the progress of the initial raid set
1977	 * synchronisation/parity calculation.
1978	 */
1979	__le64 array_resync_offset;
1980
1981	/*
1982	 * raid characteristics
1983	 */
1984	__le32 level;
1985	__le32 layout;
1986	__le32 stripe_sectors;
1987
1988	/********************************************************************
1989	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1990	 *
1991	 * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
1992	 */
1993
1994	__le32 flags; /* Flags defining array states for reshaping */
1995
1996	/*
1997	 * This offset tracks the progress of a raid
1998	 * set reshape in order to be able to restart it
1999	 */
2000	__le64 reshape_position;
2001
2002	/*
2003	 * These define the properties of the array in case of an interrupted reshape
2004	 */
2005	__le32 new_level;
2006	__le32 new_layout;
2007	__le32 new_stripe_sectors;
2008	__le32 delta_disks;
2009
2010	__le64 array_sectors; /* Array size in sectors */
2011
2012	/*
2013	 * Sector offsets to data on devices (reshaping).
2014	 * Needed to support out of place reshaping, thus
2015	 * not writing over any stripes whilst converting
2016	 * them from old to new layout
2017	 */
2018	__le64 data_offset;
2019	__le64 new_data_offset;
2020
2021	__le64 sectors; /* Used device size in sectors */
2022
2023	/*
2024	 * Additional Bit field of devices indicating failures to support
2025	 * up to 256 devices with the 1.9.0 on-disk metadata format
2026	 */
2027	__le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
2028
2029	__le32 incompat_features;	/* Used to indicate any incompatible features */
2030
2031	/* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
2032} __packed;
2033
2034/*
2035 * Check for reshape constraints on raid set @rs:
2036 *
2037 * - reshape function non-existent
2038 * - degraded set
2039 * - ongoing recovery
2040 * - ongoing reshape
2041 *
2042 * Returns 0 if none or -EPERM if given constraint
2043 * and error message reference in @errmsg
2044 */
2045static int rs_check_reshape(struct raid_set *rs)
2046{
2047	struct mddev *mddev = &rs->md;
2048
2049	if (!mddev->pers || !mddev->pers->check_reshape)
2050		rs->ti->error = "Reshape not supported";
2051	else if (mddev->degraded)
2052		rs->ti->error = "Can't reshape degraded raid set";
2053	else if (rs_is_recovering(rs))
2054		rs->ti->error = "Convert request on recovering raid set prohibited";
2055	else if (rs_is_reshaping(rs))
2056		rs->ti->error = "raid set already reshaping!";
2057	else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
2058		rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
2059	else
2060		return 0;
2061
2062	return -EPERM;
2063}
2064
2065static int read_disk_sb(struct md_rdev *rdev, int size, bool force_reload)
2066{
2067	BUG_ON(!rdev->sb_page);
2068
2069	if (rdev->sb_loaded && !force_reload)
2070		return 0;
2071
2072	rdev->sb_loaded = 0;
2073
2074	if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, true)) {
2075		DMERR("Failed to read superblock of device at position %d",
2076		      rdev->raid_disk);
2077		md_error(rdev->mddev, rdev);
2078		set_bit(Faulty, &rdev->flags);
2079		return -EIO;
2080	}
2081
2082	rdev->sb_loaded = 1;
2083
2084	return 0;
2085}
2086
2087static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2088{
2089	failed_devices[0] = le64_to_cpu(sb->failed_devices);
2090	memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
2091
2092	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2093		int i = ARRAY_SIZE(sb->extended_failed_devices);
2094
2095		while (i--)
2096			failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
2097	}
2098}
2099
2100static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2101{
2102	int i = ARRAY_SIZE(sb->extended_failed_devices);
2103
2104	sb->failed_devices = cpu_to_le64(failed_devices[0]);
2105	while (i--)
2106		sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
2107}
2108
2109/*
2110 * Synchronize the superblock members with the raid set properties
2111 *
2112 * All superblock data is little endian.
2113 */
2114static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
2115{
2116	bool update_failed_devices = false;
2117	unsigned int i;
2118	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2119	struct dm_raid_superblock *sb;
2120	struct raid_set *rs = container_of(mddev, struct raid_set, md);
2121
2122	/* No metadata device, no superblock */
2123	if (!rdev->meta_bdev)
2124		return;
2125
2126	BUG_ON(!rdev->sb_page);
2127
2128	sb = page_address(rdev->sb_page);
2129
2130	sb_retrieve_failed_devices(sb, failed_devices);
2131
2132	for (i = 0; i < rs->raid_disks; i++)
2133		if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
2134			update_failed_devices = true;
2135			set_bit(i, (void *) failed_devices);
2136		}
2137
2138	if (update_failed_devices)
2139		sb_update_failed_devices(sb, failed_devices);
2140
2141	sb->magic = cpu_to_le32(DM_RAID_MAGIC);
2142	sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2143
2144	sb->num_devices = cpu_to_le32(mddev->raid_disks);
2145	sb->array_position = cpu_to_le32(rdev->raid_disk);
2146
2147	sb->events = cpu_to_le64(mddev->events);
2148
2149	sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
2150	sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
2151
2152	sb->level = cpu_to_le32(mddev->level);
2153	sb->layout = cpu_to_le32(mddev->layout);
2154	sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
2155
2156	/********************************************************************
2157	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
2158	 *
2159	 * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
2160	 */
2161	sb->new_level = cpu_to_le32(mddev->new_level);
2162	sb->new_layout = cpu_to_le32(mddev->new_layout);
2163	sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
2164
2165	sb->delta_disks = cpu_to_le32(mddev->delta_disks);
2166
2167	smp_rmb(); /* Make sure we access most recent reshape position */
2168	sb->reshape_position = cpu_to_le64(mddev->reshape_position);
2169	if (le64_to_cpu(sb->reshape_position) != MaxSector) {
2170		/* Flag ongoing reshape */
2171		sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
2172
2173		if (mddev->delta_disks < 0 || mddev->reshape_backwards)
2174			sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
2175	} else {
2176		/* Clear reshape flags */
2177		sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
2178	}
2179
2180	sb->array_sectors = cpu_to_le64(mddev->array_sectors);
2181	sb->data_offset = cpu_to_le64(rdev->data_offset);
2182	sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
2183	sb->sectors = cpu_to_le64(rdev->sectors);
2184	sb->incompat_features = cpu_to_le32(0);
2185
2186	/* Zero out the rest of the payload after the size of the superblock */
2187	memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
2188}
2189
2190/*
2191 * super_load
2192 *
2193 * This function creates a superblock if one is not found on the device
2194 * and will decide which superblock to use if there's a choice.
2195 *
2196 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
2197 */
2198static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
2199{
2200	int r;
2201	struct dm_raid_superblock *sb;
2202	struct dm_raid_superblock *refsb;
2203	uint64_t events_sb, events_refsb;
2204
2205	r = read_disk_sb(rdev, rdev->sb_size, false);
2206	if (r)
2207		return r;
2208
2209	sb = page_address(rdev->sb_page);
2210
2211	/*
2212	 * Two cases that we want to write new superblocks and rebuild:
2213	 * 1) New device (no matching magic number)
2214	 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
2215	 */
2216	if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
2217	    (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
2218		super_sync(rdev->mddev, rdev);
2219
2220		set_bit(FirstUse, &rdev->flags);
2221		sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2222
2223		/* Force writing of superblocks to disk */
2224		set_bit(MD_SB_CHANGE_DEVS, &rdev->mddev->sb_flags);
2225
2226		/* Any superblock is better than none, choose that if given */
2227		return refdev ? 0 : 1;
2228	}
2229
2230	if (!refdev)
2231		return 1;
2232
2233	events_sb = le64_to_cpu(sb->events);
2234
2235	refsb = page_address(refdev->sb_page);
2236	events_refsb = le64_to_cpu(refsb->events);
2237
2238	return (events_sb > events_refsb) ? 1 : 0;
2239}
2240
2241static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
2242{
2243	int role;
 
2244	struct mddev *mddev = &rs->md;
2245	uint64_t events_sb;
2246	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2247	struct dm_raid_superblock *sb;
2248	uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
2249	struct md_rdev *r;
2250	struct dm_raid_superblock *sb2;
2251
2252	sb = page_address(rdev->sb_page);
2253	events_sb = le64_to_cpu(sb->events);
2254
2255	/*
2256	 * Initialise to 1 if this is a new superblock.
2257	 */
2258	mddev->events = events_sb ? : 1;
2259
2260	mddev->reshape_position = MaxSector;
2261
2262	mddev->raid_disks = le32_to_cpu(sb->num_devices);
2263	mddev->level = le32_to_cpu(sb->level);
2264	mddev->layout = le32_to_cpu(sb->layout);
2265	mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
2266
2267	/*
2268	 * Reshaping is supported, e.g. reshape_position is valid
2269	 * in superblock and superblock content is authoritative.
2270	 */
2271	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2272		/* Superblock is authoritative wrt given raid set layout! */
2273		mddev->new_level = le32_to_cpu(sb->new_level);
2274		mddev->new_layout = le32_to_cpu(sb->new_layout);
2275		mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
2276		mddev->delta_disks = le32_to_cpu(sb->delta_disks);
2277		mddev->array_sectors = le64_to_cpu(sb->array_sectors);
2278
2279		/* raid was reshaping and got interrupted */
2280		if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2281			if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2282				DMERR("Reshape requested but raid set is still reshaping");
2283				return -EINVAL;
2284			}
2285
2286			if (mddev->delta_disks < 0 ||
2287			    (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2288				mddev->reshape_backwards = 1;
2289			else
2290				mddev->reshape_backwards = 0;
2291
2292			mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2293			rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
2294		}
2295
2296	} else {
2297		/*
2298		 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2299		 */
2300		struct raid_type *rt_cur = get_raid_type_by_ll(mddev->level, mddev->layout);
2301		struct raid_type *rt_new = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
2302
2303		if (rs_takeover_requested(rs)) {
2304			if (rt_cur && rt_new)
2305				DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",
2306				      rt_cur->name, rt_new->name);
2307			else
2308				DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");
2309			return -EINVAL;
2310		} else if (rs_reshape_requested(rs)) {
2311			DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");
2312			if (mddev->layout != mddev->new_layout) {
2313				if (rt_cur && rt_new)
2314					DMERR("	 current layout %s vs new layout %s",
2315					      rt_cur->name, rt_new->name);
2316				else
2317					DMERR("	 current layout 0x%X vs new layout 0x%X",
2318					      le32_to_cpu(sb->layout), mddev->new_layout);
2319			}
2320			if (mddev->chunk_sectors != mddev->new_chunk_sectors)
2321				DMERR("	 current stripe sectors %u vs new stripe sectors %u",
2322				      mddev->chunk_sectors, mddev->new_chunk_sectors);
2323			if (rs->delta_disks)
2324				DMERR("	 current %u disks vs new %u disks",
2325				      mddev->raid_disks, mddev->raid_disks + rs->delta_disks);
2326			if (rs_is_raid10(rs)) {
2327				DMERR("	 Old layout: %s w/ %u copies",
2328				      raid10_md_layout_to_format(mddev->layout),
2329				      raid10_md_layout_to_copies(mddev->layout));
2330				DMERR("	 New layout: %s w/ %u copies",
2331				      raid10_md_layout_to_format(mddev->new_layout),
2332				      raid10_md_layout_to_copies(mddev->new_layout));
2333			}
2334			return -EINVAL;
2335		}
2336
2337		DMINFO("Discovered old metadata format; upgrading to extended metadata format");
2338	}
2339
2340	if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2341		mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2342
2343	/*
2344	 * During load, we set FirstUse if a new superblock was written.
2345	 * There are two reasons we might not have a superblock:
2346	 * 1) The raid set is brand new - in which case, all of the
2347	 *    devices must have their In_sync bit set.	Also,
2348	 *    recovery_cp must be 0, unless forced.
2349	 * 2) This is a new device being added to an old raid set
2350	 *    and the new device needs to be rebuilt - in which
2351	 *    case the In_sync bit will /not/ be set and
2352	 *    recovery_cp must be MaxSector.
2353	 * 3) This is/are a new device(s) being added to an old
2354	 *    raid set during takeover to a higher raid level
2355	 *    to provide capacity for redundancy or during reshape
2356	 *    to add capacity to grow the raid set.
2357	 */
 
2358	rdev_for_each(r, mddev) {
2359		if (test_bit(Journal, &rdev->flags))
2360			continue;
2361
2362		if (test_bit(FirstUse, &r->flags))
2363			new_devs++;
2364
2365		if (!test_bit(In_sync, &r->flags)) {
2366			DMINFO("Device %d specified for rebuild; clearing superblock",
2367				r->raid_disk);
2368			rebuilds++;
2369
2370			if (test_bit(FirstUse, &r->flags))
2371				rebuild_and_new++;
2372		}
 
 
2373	}
2374
2375	if (new_devs == rs->raid_disks || !rebuilds) {
2376		/* Replace a broken device */
 
 
2377		if (new_devs == rs->raid_disks) {
2378			DMINFO("Superblocks created for new raid set");
2379			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2380		} else if (new_devs != rebuilds &&
2381			   new_devs != rs->delta_disks) {
2382			DMERR("New device injected into existing raid set without "
2383			      "'delta_disks' or 'rebuild' parameter specified");
2384			return -EINVAL;
2385		}
2386	} else if (new_devs && new_devs != rebuilds) {
2387		DMERR("%u 'rebuild' devices cannot be injected into"
2388		      " a raid set with %u other first-time devices",
2389		      rebuilds, new_devs);
2390		return -EINVAL;
2391	} else if (rebuilds) {
2392		if (rebuild_and_new && rebuilds != rebuild_and_new) {
2393			DMERR("new device%s provided without 'rebuild'",
2394			      new_devs > 1 ? "s" : "");
2395			return -EINVAL;
2396		} else if (!test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && rs_is_recovering(rs)) {
2397			DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2398			      (unsigned long long) mddev->recovery_cp);
2399			return -EINVAL;
2400		} else if (rs_is_reshaping(rs)) {
2401			DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2402			      (unsigned long long) mddev->reshape_position);
2403			return -EINVAL;
2404		}
2405	}
2406
2407	/*
2408	 * Now we set the Faulty bit for those devices that are
2409	 * recorded in the superblock as failed.
2410	 */
2411	sb_retrieve_failed_devices(sb, failed_devices);
2412	rdev_for_each(r, mddev) {
2413		if (test_bit(Journal, &rdev->flags) ||
2414		    !r->sb_page)
2415			continue;
2416		sb2 = page_address(r->sb_page);
2417		sb2->failed_devices = 0;
2418		memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2419
2420		/*
2421		 * Check for any device re-ordering.
2422		 */
2423		if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2424			role = le32_to_cpu(sb2->array_position);
2425			if (role < 0)
2426				continue;
2427
2428			if (role != r->raid_disk) {
2429				if (rs_is_raid10(rs) && __is_raid10_near(mddev->layout)) {
2430					if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2431					    rs->raid_disks % rs->raid10_copies) {
2432						rs->ti->error =
2433							"Cannot change raid10 near set to odd # of devices!";
2434						return -EINVAL;
2435					}
2436
2437					sb2->array_position = cpu_to_le32(r->raid_disk);
2438
2439				} else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2440					   !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2441					   !rt_is_raid1(rs->raid_type)) {
2442					rs->ti->error = "Cannot change device positions in raid set";
2443					return -EINVAL;
2444				}
2445
2446				DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2447			}
2448
2449			/*
2450			 * Partial recovery is performed on
2451			 * returning failed devices.
2452			 */
2453			if (test_bit(role, (void *) failed_devices))
2454				set_bit(Faulty, &r->flags);
2455		}
2456	}
2457
2458	return 0;
2459}
2460
2461static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2462{
2463	struct mddev *mddev = &rs->md;
2464	struct dm_raid_superblock *sb;
2465
2466	if (rs_is_raid0(rs) || !rdev->sb_page || rdev->raid_disk < 0)
2467		return 0;
2468
2469	sb = page_address(rdev->sb_page);
2470
2471	/*
2472	 * If mddev->events is not set, we know we have not yet initialized
2473	 * the array.
2474	 */
2475	if (!mddev->events && super_init_validation(rs, rdev))
2476		return -EINVAL;
2477
2478	if (le32_to_cpu(sb->compat_features) &&
2479	    le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2480		rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2481		return -EINVAL;
2482	}
2483
2484	if (sb->incompat_features) {
2485		rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2486		return -EINVAL;
2487	}
2488
2489	/* Enable bitmap creation on @rs unless no metadevs or raid0 or journaled raid4/5/6 set. */
2490	mddev->bitmap_info.offset = (rt_is_raid0(rs->raid_type) || rs->journal_dev.dev) ? 0 : to_sector(4096);
2491	mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2492
2493	if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2494		/*
2495		 * Retrieve rdev size stored in superblock to be prepared for shrink.
2496		 * Check extended superblock members are present otherwise the size
2497		 * will not be set!
2498		 */
2499		if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190)
2500			rdev->sectors = le64_to_cpu(sb->sectors);
2501
2502		rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2503		if (rdev->recovery_offset == MaxSector)
2504			set_bit(In_sync, &rdev->flags);
2505		/*
2506		 * If no reshape in progress -> we're recovering single
2507		 * disk(s) and have to set the device(s) to out-of-sync
2508		 */
2509		else if (!rs_is_reshaping(rs))
2510			clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2511	}
2512
2513	/*
2514	 * If a device comes back, set it as not In_sync and no longer faulty.
2515	 */
2516	if (test_and_clear_bit(Faulty, &rdev->flags)) {
2517		rdev->recovery_offset = 0;
2518		clear_bit(In_sync, &rdev->flags);
2519		rdev->saved_raid_disk = rdev->raid_disk;
2520	}
2521
2522	/* Reshape support -> restore respective data offsets */
2523	rdev->data_offset = le64_to_cpu(sb->data_offset);
2524	rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2525
2526	return 0;
2527}
2528
2529/*
2530 * Analyse superblocks and select the freshest.
2531 */
2532static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2533{
2534	int r;
2535	struct md_rdev *rdev, *freshest;
2536	struct mddev *mddev = &rs->md;
2537
2538	freshest = NULL;
2539	rdev_for_each(rdev, mddev) {
2540		if (test_bit(Journal, &rdev->flags))
2541			continue;
2542
2543		if (!rdev->meta_bdev)
2544			continue;
2545
2546		/* Set superblock offset/size for metadata device. */
2547		rdev->sb_start = 0;
2548		rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
2549		if (rdev->sb_size < sizeof(struct dm_raid_superblock) || rdev->sb_size > PAGE_SIZE) {
2550			DMERR("superblock size of a logical block is no longer valid");
2551			return -EINVAL;
2552		}
2553
2554		/*
2555		 * Skipping super_load due to CTR_FLAG_SYNC will cause
2556		 * the array to undergo initialization again as
2557		 * though it were new.	This is the intended effect
2558		 * of the "sync" directive.
2559		 *
2560		 * With reshaping capability added, we must ensure that
2561		 * the "sync" directive is disallowed during the reshape.
2562		 */
2563		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2564			continue;
2565
2566		r = super_load(rdev, freshest);
2567
2568		switch (r) {
2569		case 1:
2570			freshest = rdev;
2571			break;
2572		case 0:
2573			break;
2574		default:
2575			/* This is a failure to read the superblock from the metadata device. */
2576			/*
2577			 * We have to keep any raid0 data/metadata device pairs or
2578			 * the MD raid0 personality will fail to start the array.
2579			 */
2580			if (rs_is_raid0(rs))
2581				continue;
2582
2583			/*
2584			 * We keep the dm_devs to be able to emit the device tuple
2585			 * properly on the table line in raid_status() (rather than
2586			 * mistakenly acting as if '- -' got passed into the constructor).
2587			 *
2588			 * The rdev has to stay on the same_set list to allow for
2589			 * the attempt to restore faulty devices on second resume.
2590			 */
2591			rdev->raid_disk = rdev->saved_raid_disk = -1;
2592			break;
2593		}
2594	}
2595
2596	if (!freshest)
2597		return 0;
2598
2599	/*
2600	 * Validation of the freshest device provides the source of
2601	 * validation for the remaining devices.
2602	 */
2603	rs->ti->error = "Unable to assemble array: Invalid superblocks";
2604	if (super_validate(rs, freshest))
2605		return -EINVAL;
2606
2607	if (validate_raid_redundancy(rs)) {
2608		rs->ti->error = "Insufficient redundancy to activate array";
2609		return -EINVAL;
2610	}
2611
2612	rdev_for_each(rdev, mddev)
2613		if (!test_bit(Journal, &rdev->flags) &&
2614		    rdev != freshest &&
2615		    super_validate(rs, rdev))
2616			return -EINVAL;
2617	return 0;
2618}
2619
2620/*
2621 * Adjust data_offset and new_data_offset on all disk members of @rs
2622 * for out of place reshaping if requested by constructor
2623 *
2624 * We need free space at the beginning of each raid disk for forward
2625 * and at the end for backward reshapes which userspace has to provide
2626 * via remapping/reordering of space.
2627 */
2628static int rs_adjust_data_offsets(struct raid_set *rs)
2629{
2630	sector_t data_offset = 0, new_data_offset = 0;
2631	struct md_rdev *rdev;
2632
2633	/* Constructor did not request data offset change */
2634	if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2635		if (!rs_is_reshapable(rs))
2636			goto out;
2637
2638		return 0;
2639	}
2640
2641	/* HM FIXME: get In_Sync raid_dev? */
2642	rdev = &rs->dev[0].rdev;
2643
2644	if (rs->delta_disks < 0) {
2645		/*
2646		 * Removing disks (reshaping backwards):
2647		 *
2648		 * - before reshape: data is at offset 0 and free space
2649		 *		     is at end of each component LV
2650		 *
2651		 * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2652		 */
2653		data_offset = 0;
2654		new_data_offset = rs->data_offset;
2655
2656	} else if (rs->delta_disks > 0) {
2657		/*
2658		 * Adding disks (reshaping forwards):
2659		 *
2660		 * - before reshape: data is at offset rs->data_offset != 0 and
2661		 *		     free space is at begin of each component LV
2662		 *
2663		 * - after reshape: data is at offset 0 on each component LV
2664		 */
2665		data_offset = rs->data_offset;
2666		new_data_offset = 0;
2667
2668	} else {
2669		/*
2670		 * User space passes in 0 for data offset after having removed reshape space
2671		 *
2672		 * - or - (data offset != 0)
2673		 *
2674		 * Changing RAID layout or chunk size -> toggle offsets
2675		 *
2676		 * - before reshape: data is at offset rs->data_offset 0 and
2677		 *		     free space is at end of each component LV
2678		 *		     -or-
2679		 *                   data is at offset rs->data_offset != 0 and
2680		 *		     free space is at begin of each component LV
2681		 *
2682		 * - after reshape: data is at offset 0 if it was at offset != 0
2683		 *                  or at offset != 0 if it was at offset 0
2684		 *                  on each component LV
2685		 *
2686		 */
2687		data_offset = rs->data_offset ? rdev->data_offset : 0;
2688		new_data_offset = data_offset ? 0 : rs->data_offset;
2689		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2690	}
2691
2692	/*
2693	 * Make sure we got a minimum amount of free sectors per device
2694	 */
2695	if (rs->data_offset &&
2696	    bdev_nr_sectors(rdev->bdev) - rs->md.dev_sectors < MIN_FREE_RESHAPE_SPACE) {
2697		rs->ti->error = data_offset ? "No space for forward reshape" :
2698					      "No space for backward reshape";
2699		return -ENOSPC;
2700	}
2701out:
2702	/*
2703	 * Raise recovery_cp in case data_offset != 0 to
2704	 * avoid false recovery positives in the constructor.
2705	 */
2706	if (rs->md.recovery_cp < rs->md.dev_sectors)
2707		rs->md.recovery_cp += rs->dev[0].rdev.data_offset;
2708
2709	/* Adjust data offsets on all rdevs but on any raid4/5/6 journal device */
2710	rdev_for_each(rdev, &rs->md) {
2711		if (!test_bit(Journal, &rdev->flags)) {
2712			rdev->data_offset = data_offset;
2713			rdev->new_data_offset = new_data_offset;
2714		}
2715	}
2716
2717	return 0;
2718}
2719
2720/* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2721static void __reorder_raid_disk_indexes(struct raid_set *rs)
2722{
2723	int i = 0;
2724	struct md_rdev *rdev;
2725
2726	rdev_for_each(rdev, &rs->md) {
2727		if (!test_bit(Journal, &rdev->flags)) {
2728			rdev->raid_disk = i++;
2729			rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2730		}
2731	}
2732}
2733
2734/*
2735 * Setup @rs for takeover by a different raid level
2736 */
2737static int rs_setup_takeover(struct raid_set *rs)
2738{
2739	struct mddev *mddev = &rs->md;
2740	struct md_rdev *rdev;
2741	unsigned int d = mddev->raid_disks = rs->raid_disks;
2742	sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2743
2744	if (rt_is_raid10(rs->raid_type)) {
2745		if (rs_is_raid0(rs)) {
2746			/* Userpace reordered disks -> adjust raid_disk indexes */
2747			__reorder_raid_disk_indexes(rs);
2748
2749			/* raid0 -> raid10_far layout */
2750			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2751								   rs->raid10_copies);
2752		} else if (rs_is_raid1(rs))
2753			/* raid1 -> raid10_near layout */
2754			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2755								   rs->raid_disks);
2756		else
2757			return -EINVAL;
2758
2759	}
2760
2761	clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2762	mddev->recovery_cp = MaxSector;
2763
2764	while (d--) {
2765		rdev = &rs->dev[d].rdev;
2766
2767		if (test_bit(d, (void *) rs->rebuild_disks)) {
2768			clear_bit(In_sync, &rdev->flags);
2769			clear_bit(Faulty, &rdev->flags);
2770			mddev->recovery_cp = rdev->recovery_offset = 0;
2771			/* Bitmap has to be created when we do an "up" takeover */
2772			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2773		}
2774
2775		rdev->new_data_offset = new_data_offset;
2776	}
2777
2778	return 0;
2779}
2780
2781/* Prepare @rs for reshape */
2782static int rs_prepare_reshape(struct raid_set *rs)
2783{
2784	bool reshape;
2785	struct mddev *mddev = &rs->md;
2786
2787	if (rs_is_raid10(rs)) {
2788		if (rs->raid_disks != mddev->raid_disks &&
2789		    __is_raid10_near(mddev->layout) &&
2790		    rs->raid10_copies &&
2791		    rs->raid10_copies != __raid10_near_copies(mddev->layout)) {
2792			/*
2793			 * raid disk have to be multiple of data copies to allow this conversion,
2794			 *
2795			 * This is actually not a reshape it is a
2796			 * rebuild of any additional mirrors per group
2797			 */
2798			if (rs->raid_disks % rs->raid10_copies) {
2799				rs->ti->error = "Can't reshape raid10 mirror groups";
2800				return -EINVAL;
2801			}
2802
2803			/* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2804			__reorder_raid_disk_indexes(rs);
2805			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2806								   rs->raid10_copies);
2807			mddev->new_layout = mddev->layout;
2808			reshape = false;
2809		} else
2810			reshape = true;
2811
2812	} else if (rs_is_raid456(rs))
2813		reshape = true;
2814
2815	else if (rs_is_raid1(rs)) {
2816		if (rs->delta_disks) {
2817			/* Process raid1 via delta_disks */
2818			mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
2819			reshape = true;
2820		} else {
2821			/* Process raid1 without delta_disks */
2822			mddev->raid_disks = rs->raid_disks;
2823			reshape = false;
2824		}
2825	} else {
2826		rs->ti->error = "Called with bogus raid type";
2827		return -EINVAL;
2828	}
2829
2830	if (reshape) {
2831		set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2832		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2833	} else if (mddev->raid_disks < rs->raid_disks)
2834		/* Create new superblocks and bitmaps, if any new disks */
2835		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2836
2837	return 0;
2838}
2839
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2840/*
2841 * Reshape:
2842 * - change raid layout
2843 * - change chunk size
2844 * - add disks
2845 * - remove disks
2846 */
2847static int rs_setup_reshape(struct raid_set *rs)
2848{
2849	int r = 0;
2850	unsigned int cur_raid_devs, d;
2851	sector_t reshape_sectors = _get_reshape_sectors(rs);
2852	struct mddev *mddev = &rs->md;
2853	struct md_rdev *rdev;
2854
2855	mddev->delta_disks = rs->delta_disks;
2856	cur_raid_devs = mddev->raid_disks;
2857
2858	/* Ignore impossible layout change whilst adding/removing disks */
2859	if (mddev->delta_disks &&
2860	    mddev->layout != mddev->new_layout) {
2861		DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2862		mddev->new_layout = mddev->layout;
2863	}
2864
2865	/*
2866	 * Adjust array size:
2867	 *
2868	 * - in case of adding disk(s), array size has
2869	 *   to grow after the disk adding reshape,
2870	 *   which'll happen in the event handler;
2871	 *   reshape will happen forward, so space has to
2872	 *   be available at the beginning of each disk
2873	 *
2874	 * - in case of removing disk(s), array size
2875	 *   has to shrink before starting the reshape,
2876	 *   which'll happen here;
2877	 *   reshape will happen backward, so space has to
2878	 *   be available at the end of each disk
2879	 *
2880	 * - data_offset and new_data_offset are
2881	 *   adjusted for aforementioned out of place
2882	 *   reshaping based on userspace passing in
2883	 *   the "data_offset <sectors>" key/value
2884	 *   pair via the constructor
2885	 */
2886
2887	/* Add disk(s) */
2888	if (rs->delta_disks > 0) {
2889		/* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2890		for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2891			rdev = &rs->dev[d].rdev;
2892			clear_bit(In_sync, &rdev->flags);
2893
2894			/*
2895			 * save_raid_disk needs to be -1, or recovery_offset will be set to 0
2896			 * by md, which'll store that erroneously in the superblock on reshape
2897			 */
2898			rdev->saved_raid_disk = -1;
2899			rdev->raid_disk = d;
2900
2901			rdev->sectors = mddev->dev_sectors;
2902			rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
2903		}
2904
2905		mddev->reshape_backwards = 0; /* adding disk(s) -> forward reshape */
2906
2907	/* Remove disk(s) */
2908	} else if (rs->delta_disks < 0) {
2909		r = rs_set_dev_and_array_sectors(rs, rs->ti->len, true);
2910		mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2911
2912	/* Change layout and/or chunk size */
2913	} else {
2914		/*
2915		 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2916		 *
2917		 * keeping number of disks and do layout change ->
2918		 *
2919		 * toggle reshape_backward depending on data_offset:
2920		 *
2921		 * - free space upfront -> reshape forward
2922		 *
2923		 * - free space at the end -> reshape backward
2924		 *
2925		 *
2926		 * This utilizes free reshape space avoiding the need
2927		 * for userspace to move (parts of) LV segments in
2928		 * case of layout/chunksize change  (for disk
2929		 * adding/removing reshape space has to be at
2930		 * the proper address (see above with delta_disks):
2931		 *
2932		 * add disk(s)   -> begin
2933		 * remove disk(s)-> end
2934		 */
2935		mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2936	}
2937
2938	/*
2939	 * Adjust device size for forward reshape
2940	 * because md_finish_reshape() reduces it.
2941	 */
2942	if (!mddev->reshape_backwards)
2943		rdev_for_each(rdev, &rs->md)
2944			if (!test_bit(Journal, &rdev->flags))
2945				rdev->sectors += reshape_sectors;
2946
2947	return r;
2948}
2949
2950/*
2951 * If the md resync thread has updated superblock with max reshape position
2952 * at the end of a reshape but not (yet) reset the layout configuration
2953 * changes -> reset the latter.
2954 */
2955static void rs_reset_inconclusive_reshape(struct raid_set *rs)
2956{
2957	if (!rs_is_reshaping(rs) && rs_is_layout_change(rs, true)) {
2958		rs_set_cur(rs);
2959		rs->md.delta_disks = 0;
2960		rs->md.reshape_backwards = 0;
2961	}
2962}
2963
2964/*
2965 * Enable/disable discard support on RAID set depending on
2966 * RAID level and discard properties of underlying RAID members.
2967 */
2968static void configure_discard_support(struct raid_set *rs)
2969{
2970	int i;
2971	bool raid456;
2972	struct dm_target *ti = rs->ti;
2973
2974	/*
2975	 * XXX: RAID level 4,5,6 require zeroing for safety.
2976	 */
2977	raid456 = rs_is_raid456(rs);
2978
2979	for (i = 0; i < rs->raid_disks; i++) {
2980		if (!rs->dev[i].rdev.bdev ||
2981		    !bdev_max_discard_sectors(rs->dev[i].rdev.bdev))
 
 
 
 
 
2982			return;
2983
2984		if (raid456) {
2985			if (!devices_handle_discard_safely) {
2986				DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2987				DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2988				return;
2989			}
2990		}
2991	}
2992
2993	ti->num_discard_bios = 1;
2994}
2995
2996/*
2997 * Construct a RAID0/1/10/4/5/6 mapping:
2998 * Args:
2999 *	<raid_type> <#raid_params> <raid_params>{0,}	\
3000 *	<#raid_devs> [<meta_dev1> <dev1>]{1,}
3001 *
3002 * <raid_params> varies by <raid_type>.	 See 'parse_raid_params' for
3003 * details on possible <raid_params>.
3004 *
3005 * Userspace is free to initialize the metadata devices, hence the superblocks to
3006 * enforce recreation based on the passed in table parameters.
3007 *
3008 */
3009static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
3010{
3011	int r;
3012	bool resize = false;
3013	struct raid_type *rt;
3014	unsigned int num_raid_params, num_raid_devs;
3015	sector_t sb_array_sectors, rdev_sectors, reshape_sectors;
3016	struct raid_set *rs = NULL;
3017	const char *arg;
3018	struct rs_layout rs_layout;
3019	struct dm_arg_set as = { argc, argv }, as_nrd;
3020	struct dm_arg _args[] = {
3021		{ 0, as.argc, "Cannot understand number of raid parameters" },
3022		{ 1, 254, "Cannot understand number of raid devices parameters" }
3023	};
3024
 
3025	arg = dm_shift_arg(&as);
3026	if (!arg) {
3027		ti->error = "No arguments";
3028		return -EINVAL;
3029	}
3030
3031	rt = get_raid_type(arg);
3032	if (!rt) {
3033		ti->error = "Unrecognised raid_type";
3034		return -EINVAL;
3035	}
3036
3037	/* Must have <#raid_params> */
3038	if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
3039		return -EINVAL;
3040
3041	/* number of raid device tupples <meta_dev data_dev> */
3042	as_nrd = as;
3043	dm_consume_args(&as_nrd, num_raid_params);
3044	_args[1].max = (as_nrd.argc - 1) / 2;
3045	if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
3046		return -EINVAL;
3047
3048	if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
3049		ti->error = "Invalid number of supplied raid devices";
3050		return -EINVAL;
3051	}
3052
3053	rs = raid_set_alloc(ti, rt, num_raid_devs);
3054	if (IS_ERR(rs))
3055		return PTR_ERR(rs);
3056
3057	r = parse_raid_params(rs, &as, num_raid_params);
3058	if (r)
3059		goto bad;
3060
3061	r = parse_dev_params(rs, &as);
3062	if (r)
3063		goto bad;
3064
3065	rs->md.sync_super = super_sync;
3066
3067	/*
3068	 * Calculate ctr requested array and device sizes to allow
3069	 * for superblock analysis needing device sizes defined.
3070	 *
3071	 * Any existing superblock will overwrite the array and device sizes
3072	 */
3073	r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);
3074	if (r)
3075		goto bad;
3076
3077	/* Memorize just calculated, potentially larger sizes to grow the raid set in preresume */
3078	rs->array_sectors = rs->md.array_sectors;
3079	rs->dev_sectors = rs->md.dev_sectors;
3080
3081	/*
3082	 * Backup any new raid set level, layout, ...
3083	 * requested to be able to compare to superblock
3084	 * members for conversion decisions.
3085	 */
3086	rs_config_backup(rs, &rs_layout);
3087
3088	r = analyse_superblocks(ti, rs);
3089	if (r)
3090		goto bad;
3091
3092	/* All in-core metadata now as of current superblocks after calling analyse_superblocks() */
3093	sb_array_sectors = rs->md.array_sectors;
3094	rdev_sectors = __rdev_sectors(rs);
3095	if (!rdev_sectors) {
3096		ti->error = "Invalid rdev size";
3097		r = -EINVAL;
3098		goto bad;
3099	}
3100
3101
3102	reshape_sectors = _get_reshape_sectors(rs);
3103	if (rs->dev_sectors != rdev_sectors) {
3104		resize = (rs->dev_sectors != rdev_sectors - reshape_sectors);
3105		if (rs->dev_sectors > rdev_sectors - reshape_sectors)
3106			set_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3107	}
3108
3109	INIT_WORK(&rs->md.event_work, do_table_event);
3110	ti->private = rs;
3111	ti->num_flush_bios = 1;
3112	ti->needs_bio_set_dev = true;
3113
3114	/* Restore any requested new layout for conversion decision */
3115	rs_config_restore(rs, &rs_layout);
3116
3117	/*
3118	 * Now that we have any superblock metadata available,
3119	 * check for new, recovering, reshaping, to be taken over,
3120	 * to be reshaped or an existing, unchanged raid set to
3121	 * run in sequence.
3122	 */
3123	if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
3124		/* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
3125		if (rs_is_raid6(rs) &&
3126		    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
3127			ti->error = "'nosync' not allowed for new raid6 set";
3128			r = -EINVAL;
3129			goto bad;
3130		}
3131		rs_setup_recovery(rs, 0);
3132		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3133		rs_set_new(rs);
3134	} else if (rs_is_recovering(rs)) {
 
 
 
 
 
3135		/* A recovering raid set may be resized */
3136		goto size_check;
3137	} else if (rs_is_reshaping(rs)) {
3138		/* Have to reject size change request during reshape */
3139		if (resize) {
3140			ti->error = "Can't resize a reshaping raid set";
3141			r = -EPERM;
3142			goto bad;
3143		}
3144		/* skip setup rs */
3145	} else if (rs_takeover_requested(rs)) {
3146		if (rs_is_reshaping(rs)) {
3147			ti->error = "Can't takeover a reshaping raid set";
3148			r = -EPERM;
3149			goto bad;
3150		}
3151
3152		/* We can't takeover a journaled raid4/5/6 */
3153		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3154			ti->error = "Can't takeover a journaled raid4/5/6 set";
3155			r = -EPERM;
3156			goto bad;
3157		}
3158
3159		/*
3160		 * If a takeover is needed, userspace sets any additional
3161		 * devices to rebuild and we can check for a valid request here.
3162		 *
3163		 * If acceptable, set the level to the new requested
3164		 * one, prohibit requesting recovery, allow the raid
3165		 * set to run and store superblocks during resume.
3166		 */
3167		r = rs_check_takeover(rs);
3168		if (r)
3169			goto bad;
3170
3171		r = rs_setup_takeover(rs);
3172		if (r)
3173			goto bad;
3174
3175		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3176		/* Takeover ain't recovery, so disable recovery */
3177		rs_setup_recovery(rs, MaxSector);
3178		rs_set_new(rs);
3179	} else if (rs_reshape_requested(rs)) {
3180		/* Only request grow on raid set size extensions, not on reshapes. */
3181		clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3182
3183		/*
3184		 * No need to check for 'ongoing' takeover here, because takeover
3185		 * is an instant operation as oposed to an ongoing reshape.
3186		 */
3187
3188		/* We can't reshape a journaled raid4/5/6 */
3189		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3190			ti->error = "Can't reshape a journaled raid4/5/6 set";
3191			r = -EPERM;
3192			goto bad;
3193		}
3194
3195		/* Out-of-place space has to be available to allow for a reshape unless raid1! */
3196		if (reshape_sectors || rs_is_raid1(rs)) {
3197			/*
3198			 * We can only prepare for a reshape here, because the
3199			 * raid set needs to run to provide the repective reshape
3200			 * check functions via its MD personality instance.
3201			 *
3202			 * So do the reshape check after md_run() succeeded.
3203			 */
3204			r = rs_prepare_reshape(rs);
3205			if (r)
3206				goto bad;
3207
3208			/* Reshaping ain't recovery, so disable recovery */
3209			rs_setup_recovery(rs, MaxSector);
3210		}
3211		rs_set_cur(rs);
3212	} else {
3213size_check:
3214		/* May not set recovery when a device rebuild is requested */
3215		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
3216			clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3217			set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3218			rs_setup_recovery(rs, MaxSector);
3219		} else if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
3220			/*
3221			 * Set raid set to current size, i.e. size as of
3222			 * superblocks to grow to larger size in preresume.
3223			 */
3224			r = rs_set_dev_and_array_sectors(rs, sb_array_sectors, false);
3225			if (r)
3226				goto bad;
3227
3228			rs_setup_recovery(rs, rs->md.recovery_cp < rs->md.dev_sectors ? rs->md.recovery_cp : rs->md.dev_sectors);
3229		} else {
3230			/* This is no size change or it is shrinking, update size and record in superblocks */
3231			r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);
3232			if (r)
3233				goto bad;
3234
3235			if (sb_array_sectors > rs->array_sectors)
3236				set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3237		}
3238		rs_set_cur(rs);
3239	}
3240
3241	/* If constructor requested it, change data and new_data offsets */
3242	r = rs_adjust_data_offsets(rs);
3243	if (r)
3244		goto bad;
3245
3246	/* Catch any inconclusive reshape superblock content. */
3247	rs_reset_inconclusive_reshape(rs);
3248
3249	/* Start raid set read-only and assumed clean to change in raid_resume() */
3250	rs->md.ro = 1;
3251	rs->md.in_sync = 1;
3252
 
 
 
3253	/* Has to be held on running the array */
3254	mddev_suspend_and_lock_nointr(&rs->md);
3255
3256	/* Keep array frozen until resume. */
3257	md_frozen_sync_thread(&rs->md);
3258
3259	r = md_run(&rs->md);
3260	rs->md.in_sync = 0; /* Assume already marked dirty */
3261	if (r) {
3262		ti->error = "Failed to run raid array";
3263		mddev_unlock(&rs->md);
3264		goto bad;
3265	}
3266
3267	r = md_start(&rs->md);
 
3268	if (r) {
3269		ti->error = "Failed to start raid array";
3270		goto bad_unlock;
 
3271	}
3272
 
 
 
3273	/* If raid4/5/6 journal mode explicitly requested (only possible with journal dev) -> set it */
3274	if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
3275		r = r5c_journal_mode_set(&rs->md, rs->journal_dev.mode);
3276		if (r) {
3277			ti->error = "Failed to set raid4/5/6 journal mode";
3278			goto bad_unlock;
 
3279		}
3280	}
3281
 
3282	set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags);
3283
3284	/* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
3285	if (rs_is_raid456(rs)) {
3286		r = rs_set_raid456_stripe_cache(rs);
3287		if (r)
3288			goto bad_unlock;
3289	}
3290
3291	/* Now do an early reshape check */
3292	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3293		r = rs_check_reshape(rs);
3294		if (r)
3295			goto bad_unlock;
3296
3297		/* Restore new, ctr requested layout to perform check */
3298		rs_config_restore(rs, &rs_layout);
3299
3300		if (rs->md.pers->start_reshape) {
3301			r = rs->md.pers->check_reshape(&rs->md);
3302			if (r) {
3303				ti->error = "Reshape check failed";
3304				goto bad_unlock;
3305			}
3306		}
3307	}
3308
3309	/* Disable/enable discard support on raid set. */
3310	configure_discard_support(rs);
3311
3312	mddev_unlock(&rs->md);
3313	return 0;
3314
3315bad_unlock:
 
 
 
3316	md_stop(&rs->md);
3317	mddev_unlock(&rs->md);
3318bad:
3319	raid_set_free(rs);
3320
3321	return r;
3322}
3323
3324static void raid_dtr(struct dm_target *ti)
3325{
3326	struct raid_set *rs = ti->private;
3327
3328	mddev_lock_nointr(&rs->md);
3329	md_stop(&rs->md);
3330	mddev_unlock(&rs->md);
3331
3332	if (work_pending(&rs->md.event_work))
3333		flush_work(&rs->md.event_work);
3334	raid_set_free(rs);
3335}
3336
3337static int raid_map(struct dm_target *ti, struct bio *bio)
3338{
3339	struct raid_set *rs = ti->private;
3340	struct mddev *mddev = &rs->md;
3341
3342	/*
3343	 * If we're reshaping to add disk(s), ti->len and
3344	 * mddev->array_sectors will differ during the process
3345	 * (ti->len > mddev->array_sectors), so we have to requeue
3346	 * bios with addresses > mddev->array_sectors here or
3347	 * there will occur accesses past EOD of the component
3348	 * data images thus erroring the raid set.
3349	 */
3350	if (unlikely(bio_has_data(bio) && bio_end_sector(bio) > mddev->array_sectors))
3351		return DM_MAPIO_REQUEUE;
3352
3353	if (unlikely(!md_handle_request(mddev, bio)))
3354		return DM_MAPIO_REQUEUE;
3355
3356	return DM_MAPIO_SUBMITTED;
3357}
3358
3359/* Return sync state string for @state */
3360enum sync_state { st_frozen, st_reshape, st_resync, st_check, st_repair, st_recover, st_idle };
3361static const char *sync_str(enum sync_state state)
3362{
3363	/* Has to be in above sync_state order! */
3364	static const char *sync_strs[] = {
3365		"frozen",
3366		"reshape",
3367		"resync",
3368		"check",
3369		"repair",
3370		"recover",
3371		"idle"
3372	};
3373
3374	return __within_range(state, 0, ARRAY_SIZE(sync_strs) - 1) ? sync_strs[state] : "undef";
3375};
3376
3377/* Return enum sync_state for @mddev derived from @recovery flags */
3378static enum sync_state decipher_sync_action(struct mddev *mddev, unsigned long recovery)
3379{
3380	if (test_bit(MD_RECOVERY_FROZEN, &recovery))
3381		return st_frozen;
3382
3383	/* The MD sync thread can be done with io or be interrupted but still be running */
3384	if (!test_bit(MD_RECOVERY_DONE, &recovery) &&
3385	    (test_bit(MD_RECOVERY_RUNNING, &recovery) ||
3386	     (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery)))) {
3387		if (test_bit(MD_RECOVERY_RESHAPE, &recovery))
3388			return st_reshape;
3389
3390		if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
3391			if (!test_bit(MD_RECOVERY_REQUESTED, &recovery))
3392				return st_resync;
3393			if (test_bit(MD_RECOVERY_CHECK, &recovery))
3394				return st_check;
3395			return st_repair;
3396		}
3397
3398		if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3399			return st_recover;
3400
3401		if (mddev->reshape_position != MaxSector)
3402			return st_reshape;
3403	}
3404
3405	return st_idle;
3406}
3407
3408/*
3409 * Return status string for @rdev
3410 *
3411 * Status characters:
3412 *
3413 *  'D' = Dead/Failed raid set component or raid4/5/6 journal device
3414 *  'a' = Alive but not in-sync raid set component _or_ alive raid4/5/6 'write_back' journal device
3415 *  'A' = Alive and in-sync raid set component _or_ alive raid4/5/6 'write_through' journal device
3416 *  '-' = Non-existing device (i.e. uspace passed '- -' into the ctr)
3417 */
3418static const char *__raid_dev_status(struct raid_set *rs, struct md_rdev *rdev)
3419{
3420	if (!rdev->bdev)
3421		return "-";
3422	else if (test_bit(Faulty, &rdev->flags))
3423		return "D";
3424	else if (test_bit(Journal, &rdev->flags))
3425		return (rs->journal_dev.mode == R5C_JOURNAL_MODE_WRITE_THROUGH) ? "A" : "a";
3426	else if (test_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags) ||
3427		 (!test_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags) &&
3428		  !test_bit(In_sync, &rdev->flags)))
3429		return "a";
3430	else
3431		return "A";
3432}
3433
3434/* Helper to return resync/reshape progress for @rs and runtime flags for raid set in sync / resynching */
3435static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery,
3436				enum sync_state state, sector_t resync_max_sectors)
3437{
3438	sector_t r;
 
3439	struct mddev *mddev = &rs->md;
3440
3441	clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3442	clear_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3443
3444	if (rs_is_raid0(rs)) {
3445		r = resync_max_sectors;
3446		set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3447
3448	} else {
 
 
3449		if (state == st_idle && !test_bit(MD_RECOVERY_INTR, &recovery))
3450			r = mddev->recovery_cp;
3451		else
3452			r = mddev->curr_resync_completed;
3453
3454		if (state == st_idle && r >= resync_max_sectors) {
3455			/*
3456			 * Sync complete.
3457			 */
3458			/* In case we have finished recovering, the array is in sync. */
3459			if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3460				set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3461
3462		} else if (state == st_recover)
3463			/*
3464			 * In case we are recovering, the array is not in sync
3465			 * and health chars should show the recovering legs.
3466			 *
3467			 * Already retrieved recovery offset from curr_resync_completed above.
3468			 */
3469			;
3470
3471		else if (state == st_resync || state == st_reshape)
 
 
 
 
 
 
3472			/*
3473			 * If "resync/reshape" is occurring, the raid set
3474			 * is or may be out of sync hence the health
3475			 * characters shall be 'a'.
3476			 */
3477			set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3478
3479		else if (state == st_check || state == st_repair)
3480			/*
3481			 * If "check" or "repair" is occurring, the raid set has
3482			 * undergone an initial sync and the health characters
3483			 * should not be 'a' anymore.
3484			 */
3485			set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3486
3487		else if (test_bit(MD_RECOVERY_NEEDED, &recovery))
 
 
3488			/*
3489			 * We are idle and recovery is needed, prevent 'A' chars race
3490			 * caused by components still set to in-sync by constructor.
3491			 */
3492			set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
 
3493
3494		else {
3495			/*
3496			 * We are idle and the raid set may be doing an initial
3497			 * sync, or it may be rebuilding individual components.
3498			 * If all the devices are In_sync, then it is the raid set
3499			 * that is being initialized.
3500			 */
3501			struct md_rdev *rdev;
3502
3503			set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3504			rdev_for_each(rdev, mddev)
3505				if (!test_bit(Journal, &rdev->flags) &&
3506				    !test_bit(In_sync, &rdev->flags)) {
3507					clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3508					break;
3509				}
3510		}
3511	}
3512
3513	return min(r, resync_max_sectors);
3514}
3515
3516/* Helper to return @dev name or "-" if !@dev */
3517static const char *__get_dev_name(struct dm_dev *dev)
3518{
3519	return dev ? dev->name : "-";
3520}
3521
3522static void raid_status(struct dm_target *ti, status_type_t type,
3523			unsigned int status_flags, char *result, unsigned int maxlen)
3524{
3525	struct raid_set *rs = ti->private;
3526	struct mddev *mddev = &rs->md;
3527	struct r5conf *conf = rs_is_raid456(rs) ? mddev->private : NULL;
3528	int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3529	unsigned long recovery;
3530	unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3531	unsigned int sz = 0;
3532	unsigned int rebuild_writemostly_count = 0;
 
3533	sector_t progress, resync_max_sectors, resync_mismatches;
3534	enum sync_state state;
3535	struct raid_type *rt;
3536
3537	switch (type) {
3538	case STATUSTYPE_INFO:
3539		/* *Should* always succeed */
3540		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3541		if (!rt)
3542			return;
3543
3544		DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3545
3546		/* Access most recent mddev properties for status output */
3547		smp_rmb();
 
3548		/* Get sensible max sectors even if raid set not yet started */
3549		resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3550				      mddev->resync_max_sectors : mddev->dev_sectors;
3551		recovery = rs->md.recovery;
3552		state = decipher_sync_action(mddev, recovery);
3553		progress = rs_get_progress(rs, recovery, state, resync_max_sectors);
3554		resync_mismatches = mddev->last_sync_action == ACTION_CHECK ?
3555				    atomic64_read(&mddev->resync_mismatches) : 0;
 
3556
3557		/* HM FIXME: do we want another state char for raid0? It shows 'D'/'A'/'-' now */
3558		for (i = 0; i < rs->raid_disks; i++)
3559			DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3560
3561		/*
3562		 * In-sync/Reshape ratio:
3563		 *  The in-sync ratio shows the progress of:
3564		 *   - Initializing the raid set
3565		 *   - Rebuilding a subset of devices of the raid set
3566		 *  The user can distinguish between the two by referring
3567		 *  to the status characters.
3568		 *
3569		 *  The reshape ratio shows the progress of
3570		 *  changing the raid layout or the number of
3571		 *  disks of a raid set
3572		 */
3573		DMEMIT(" %llu/%llu", (unsigned long long) progress,
3574				     (unsigned long long) resync_max_sectors);
3575
3576		/*
3577		 * v1.5.0+:
3578		 *
3579		 * Sync action:
3580		 *   See Documentation/admin-guide/device-mapper/dm-raid.rst for
3581		 *   information on each of these states.
3582		 */
3583		DMEMIT(" %s", sync_str(state));
3584
3585		/*
3586		 * v1.5.0+:
3587		 *
3588		 * resync_mismatches/mismatch_cnt
3589		 *   This field shows the number of discrepancies found when
3590		 *   performing a "check" of the raid set.
3591		 */
3592		DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3593
3594		/*
3595		 * v1.9.0+:
3596		 *
3597		 * data_offset (needed for out of space reshaping)
3598		 *   This field shows the data offset into the data
3599		 *   image LV where the first stripes data starts.
3600		 *
3601		 * We keep data_offset equal on all raid disks of the set,
3602		 * so retrieving it from the first raid disk is sufficient.
3603		 */
3604		DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
3605
3606		/*
3607		 * v1.10.0+:
3608		 */
3609		DMEMIT(" %s", test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags) ?
3610			      __raid_dev_status(rs, &rs->journal_dev.rdev) : "-");
3611		break;
3612
3613	case STATUSTYPE_TABLE:
3614		/* Report the table line string you would use to construct this raid set */
3615
3616		/*
3617		 * Count any rebuild or writemostly argument pairs and subtract the
3618		 * hweight count being added below of any rebuild and writemostly ctr flags.
3619		 */
3620		for (i = 0; i < rs->raid_disks; i++) {
3621			rebuild_writemostly_count += (test_bit(i, (void *) rs->rebuild_disks) ? 2 : 0) +
3622						     (test_bit(WriteMostly, &rs->dev[i].rdev.flags) ? 2 : 0);
3623		}
3624		rebuild_writemostly_count -= (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) ? 2 : 0) +
3625					     (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags) ? 2 : 0);
3626		/* Calculate raid parameter count based on ^ rebuild/writemostly argument counts and ctr flags set. */
3627		raid_param_cnt += rebuild_writemostly_count +
3628				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3629				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
 
 
 
3630		/* Emit table line */
3631		/* This has to be in the documented order for userspace! */
3632		DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3633		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3634			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
3635		if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3636			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3637		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags))
3638			for (i = 0; i < rs->raid_disks; i++)
3639				if (test_bit(i, (void *) rs->rebuild_disks))
3640					DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD), i);
 
3641		if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3642			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3643					  mddev->bitmap_info.daemon_sleep);
3644		if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3645			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3646					 mddev->sync_speed_min);
3647		if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3648			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3649					 mddev->sync_speed_max);
3650		if (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags))
3651			for (i = 0; i < rs->raid_disks; i++)
3652				if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3653					DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3654					       rs->dev[i].rdev.raid_disk);
3655		if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3656			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3657					  mddev->bitmap_info.max_write_behind);
3658		if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3659			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3660					 max_nr_stripes);
3661		if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3662			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3663					   (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3664		if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3665			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3666					 raid10_md_layout_to_copies(mddev->layout));
3667		if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3668			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3669					 raid10_md_layout_to_format(mddev->layout));
3670		if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3671			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3672					 max(rs->delta_disks, mddev->delta_disks));
3673		if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3674			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3675					   (unsigned long long) rs->data_offset);
3676		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags))
3677			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV),
3678					__get_dev_name(rs->journal_dev.dev));
3679		if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags))
3680			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE),
3681					 md_journal_mode_to_dm_raid(rs->journal_dev.mode));
3682		DMEMIT(" %d", rs->raid_disks);
3683		for (i = 0; i < rs->raid_disks; i++)
3684			DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
3685					 __get_dev_name(rs->dev[i].data_dev));
3686		break;
3687
3688	case STATUSTYPE_IMA:
3689		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3690		if (!rt)
3691			return;
3692
3693		DMEMIT_TARGET_NAME_VERSION(ti->type);
3694		DMEMIT(",raid_type=%s,raid_disks=%d", rt->name, mddev->raid_disks);
3695
3696		/* Access most recent mddev properties for status output */
3697		smp_rmb();
3698		recovery = rs->md.recovery;
3699		state = decipher_sync_action(mddev, recovery);
3700		DMEMIT(",raid_state=%s", sync_str(state));
3701
3702		for (i = 0; i < rs->raid_disks; i++) {
3703			DMEMIT(",raid_device_%d_status=", i);
3704			DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3705		}
3706
3707		if (rt_is_raid456(rt)) {
3708			DMEMIT(",journal_dev_mode=");
3709			switch (rs->journal_dev.mode) {
3710			case R5C_JOURNAL_MODE_WRITE_THROUGH:
3711				DMEMIT("%s",
3712				       _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_THROUGH].param);
3713				break;
3714			case R5C_JOURNAL_MODE_WRITE_BACK:
3715				DMEMIT("%s",
3716				       _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_BACK].param);
3717				break;
3718			default:
3719				DMEMIT("invalid");
3720				break;
3721			}
3722		}
3723		DMEMIT(";");
3724		break;
3725	}
3726}
3727
3728static int raid_message(struct dm_target *ti, unsigned int argc, char **argv,
3729			char *result, unsigned int maxlen)
3730{
3731	struct raid_set *rs = ti->private;
3732	struct mddev *mddev = &rs->md;
3733	int ret = 0;
3734
3735	if (!mddev->pers || !mddev->pers->sync_request)
3736		return -EINVAL;
3737
3738	if (test_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags) ||
3739	    test_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags))
3740		return -EBUSY;
 
3741
3742	if (!strcasecmp(argv[0], "frozen")) {
3743		ret = mddev_lock(mddev);
3744		if (ret)
3745			return ret;
3746
3747		md_frozen_sync_thread(mddev);
3748		mddev_unlock(mddev);
3749	} else if (!strcasecmp(argv[0], "idle")) {
3750		ret = mddev_lock(mddev);
3751		if (ret)
3752			return ret;
3753
3754		md_idle_sync_thread(mddev);
3755		mddev_unlock(mddev);
3756	}
3757
3758	clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3759	if (decipher_sync_action(mddev, mddev->recovery) != st_idle)
3760		return -EBUSY;
3761	else if (!strcasecmp(argv[0], "resync"))
3762		; /* MD_RECOVERY_NEEDED set below */
3763	else if (!strcasecmp(argv[0], "recover"))
3764		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3765	else {
3766		if (!strcasecmp(argv[0], "check")) {
3767			set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3768			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3769			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3770		} else if (!strcasecmp(argv[0], "repair")) {
3771			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3772			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3773		} else
3774			return -EINVAL;
3775	}
3776	if (mddev->ro == 2) {
3777		/* A write to sync_action is enough to justify
3778		 * canceling read-auto mode
3779		 */
3780		mddev->ro = 0;
3781		if (!mddev->suspended)
3782			md_wakeup_thread(mddev->sync_thread);
3783	}
3784	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3785	if (!mddev->suspended)
3786		md_wakeup_thread(mddev->thread);
3787
3788	return 0;
3789}
3790
3791static int raid_iterate_devices(struct dm_target *ti,
3792				iterate_devices_callout_fn fn, void *data)
3793{
3794	struct raid_set *rs = ti->private;
3795	unsigned int i;
3796	int r = 0;
3797
3798	for (i = 0; !r && i < rs->raid_disks; i++) {
3799		if (rs->dev[i].data_dev) {
3800			r = fn(ti, rs->dev[i].data_dev,
3801			       0, /* No offset on data devs */
3802			       rs->md.dev_sectors, data);
3803		}
3804	}
3805
3806	return r;
3807}
3808
3809static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3810{
3811	struct raid_set *rs = ti->private;
3812	unsigned int chunk_size_bytes = to_bytes(rs->md.chunk_sectors);
3813
3814	limits->io_min = chunk_size_bytes;
3815	limits->io_opt = chunk_size_bytes * mddev_data_stripes(rs);
3816}
3817
3818static void raid_presuspend(struct dm_target *ti)
3819{
3820	struct raid_set *rs = ti->private;
3821	struct mddev *mddev = &rs->md;
3822
3823	/*
3824	 * From now on, disallow raid_message() to change sync_thread until
3825	 * resume, raid_postsuspend() is too late.
3826	 */
3827	set_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags);
3828
3829	if (!reshape_interrupted(mddev))
3830		return;
3831
3832	/*
3833	 * For raid456, if reshape is interrupted, IO across reshape position
3834	 * will never make progress, while caller will wait for IO to be done.
3835	 * Inform raid456 to handle those IO to prevent deadlock.
3836	 */
3837	if (mddev->pers && mddev->pers->prepare_suspend)
3838		mddev->pers->prepare_suspend(mddev);
3839}
3840
3841static void raid_presuspend_undo(struct dm_target *ti)
3842{
3843	struct raid_set *rs = ti->private;
3844
3845	clear_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags);
3846}
3847
3848static void raid_postsuspend(struct dm_target *ti)
3849{
3850	struct raid_set *rs = ti->private;
3851
3852	if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
3853		/*
3854		 * sync_thread must be stopped during suspend, and writes have
3855		 * to be stopped before suspending to avoid deadlocks.
3856		 */
3857		md_stop_writes(&rs->md);
3858		mddev_suspend(&rs->md, false);
 
3859	}
3860}
3861
3862static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3863{
3864	int i;
3865	uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];
3866	unsigned long flags;
3867	bool cleared = false;
3868	struct dm_raid_superblock *sb;
3869	struct mddev *mddev = &rs->md;
3870	struct md_rdev *r;
3871
3872	/* RAID personalities have to provide hot add/remove methods or we need to bail out. */
3873	if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)
3874		return;
3875
3876	memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));
3877
3878	for (i = 0; i < rs->raid_disks; i++) {
3879		r = &rs->dev[i].rdev;
3880		/* HM FIXME: enhance journal device recovery processing */
3881		if (test_bit(Journal, &r->flags))
3882			continue;
3883
3884		if (test_bit(Faulty, &r->flags) &&
3885		    r->meta_bdev && !read_disk_sb(r, r->sb_size, true)) {
3886			DMINFO("Faulty %s device #%d has readable super block."
3887			       "  Attempting to revive it.",
3888			       rs->raid_type->name, i);
3889
3890			/*
3891			 * Faulty bit may be set, but sometimes the array can
3892			 * be suspended before the personalities can respond
3893			 * by removing the device from the array (i.e. calling
3894			 * 'hot_remove_disk').	If they haven't yet removed
3895			 * the failed device, its 'raid_disk' number will be
3896			 * '>= 0' - meaning we must call this function
3897			 * ourselves.
3898			 */
3899			flags = r->flags;
3900			clear_bit(In_sync, &r->flags); /* Mandatory for hot remove. */
3901			if (r->raid_disk >= 0) {
3902				if (mddev->pers->hot_remove_disk(mddev, r)) {
3903					/* Failed to revive this device, try next */
3904					r->flags = flags;
3905					continue;
3906				}
3907			} else
3908				r->raid_disk = r->saved_raid_disk = i;
3909
3910			clear_bit(Faulty, &r->flags);
3911			clear_bit(WriteErrorSeen, &r->flags);
3912
3913			if (mddev->pers->hot_add_disk(mddev, r)) {
3914				/* Failed to revive this device, try next */
3915				r->raid_disk = r->saved_raid_disk = -1;
3916				r->flags = flags;
3917			} else {
3918				clear_bit(In_sync, &r->flags);
3919				r->recovery_offset = 0;
3920				set_bit(i, (void *) cleared_failed_devices);
3921				cleared = true;
3922			}
3923		}
3924	}
3925
3926	/* If any failed devices could be cleared, update all sbs failed_devices bits */
3927	if (cleared) {
3928		uint64_t failed_devices[DISKS_ARRAY_ELEMS];
3929
3930		rdev_for_each(r, &rs->md) {
3931			if (test_bit(Journal, &r->flags))
3932				continue;
3933
3934			sb = page_address(r->sb_page);
3935			sb_retrieve_failed_devices(sb, failed_devices);
3936
3937			for (i = 0; i < DISKS_ARRAY_ELEMS; i++)
3938				failed_devices[i] &= ~cleared_failed_devices[i];
3939
3940			sb_update_failed_devices(sb, failed_devices);
3941		}
3942	}
3943}
3944
3945static int __load_dirty_region_bitmap(struct raid_set *rs)
3946{
3947	int r = 0;
3948
3949	/* Try loading the bitmap unless "raid0", which does not have one */
3950	if (!rs_is_raid0(rs) &&
3951	    !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
3952		struct mddev *mddev = &rs->md;
3953
3954		r = mddev->bitmap_ops->load(mddev);
3955		if (r)
3956			DMERR("Failed to load bitmap");
3957	}
3958
3959	return r;
3960}
3961
3962/* Enforce updating all superblocks */
3963static void rs_update_sbs(struct raid_set *rs)
3964{
3965	struct mddev *mddev = &rs->md;
3966	int ro = mddev->ro;
3967
3968	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
3969	mddev->ro = 0;
3970	md_update_sb(mddev, 1);
3971	mddev->ro = ro;
3972}
3973
3974/*
3975 * Reshape changes raid algorithm of @rs to new one within personality
3976 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3977 * disks from a raid set thus growing/shrinking it or resizes the set
3978 *
3979 * Call mddev_lock_nointr() before!
3980 */
3981static int rs_start_reshape(struct raid_set *rs)
3982{
3983	int r;
3984	struct mddev *mddev = &rs->md;
3985	struct md_personality *pers = mddev->pers;
3986
3987	/* Don't allow the sync thread to work until the table gets reloaded. */
3988	set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
3989
3990	r = rs_setup_reshape(rs);
3991	if (r)
3992		return r;
3993
3994	/*
3995	 * Check any reshape constraints enforced by the personalility
3996	 *
3997	 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3998	 */
3999	r = pers->check_reshape(mddev);
4000	if (r) {
4001		rs->ti->error = "pers->check_reshape() failed";
4002		return r;
4003	}
4004
4005	/*
4006	 * Personality may not provide start reshape method in which
4007	 * case check_reshape above has already covered everything
4008	 */
4009	if (pers->start_reshape) {
4010		r = pers->start_reshape(mddev);
4011		if (r) {
4012			rs->ti->error = "pers->start_reshape() failed";
4013			return r;
4014		}
4015	}
4016
4017	/*
4018	 * Now reshape got set up, update superblocks to
4019	 * reflect the fact so that a table reload will
4020	 * access proper superblock content in the ctr.
4021	 */
4022	rs_update_sbs(rs);
4023
4024	return 0;
4025}
4026
4027static int raid_preresume(struct dm_target *ti)
4028{
4029	int r;
4030	struct raid_set *rs = ti->private;
4031	struct mddev *mddev = &rs->md;
4032
4033	/* This is a resume after a suspend of the set -> it's already started. */
4034	if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
4035		return 0;
4036
4037	/* If different and no explicit grow request, expose MD array size as of superblock. */
4038	if (!test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags) &&
4039	    rs->array_sectors != mddev->array_sectors)
4040		rs_set_capacity(rs);
4041
4042	/*
4043	 * The superblocks need to be updated on disk if the
4044	 * array is new or new devices got added (thus zeroed
4045	 * out by userspace) or __load_dirty_region_bitmap
4046	 * will overwrite them in core with old data or fail.
4047	 */
4048	if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
4049		rs_update_sbs(rs);
4050
4051	/* Load the bitmap from disk unless raid0 */
4052	r = __load_dirty_region_bitmap(rs);
4053	if (r)
4054		return r;
4055
4056	/* We are extending the raid set size, adjust mddev/md_rdev sizes and set capacity. */
4057	if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
4058		mddev->array_sectors = rs->array_sectors;
4059		mddev->dev_sectors = rs->dev_sectors;
4060		rs_set_rdev_sectors(rs);
4061		rs_set_capacity(rs);
4062	}
4063
4064	/* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) or grown device size */
4065	if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
4066	    (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags) ||
4067	     (rs->requested_bitmap_chunk_sectors &&
4068	       mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)))) {
4069		int chunksize = to_bytes(rs->requested_bitmap_chunk_sectors) ?: mddev->bitmap_info.chunksize;
4070
4071		r = mddev->bitmap_ops->resize(mddev, mddev->dev_sectors,
4072					      chunksize, false);
4073		if (r)
4074			DMERR("Failed to resize bitmap");
4075	}
4076
4077	/* Check for any resize/reshape on @rs and adjust/initiate */
 
 
4078	if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
4079		set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
4080		mddev->resync_min = mddev->recovery_cp;
4081		if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags))
4082			mddev->resync_max_sectors = mddev->dev_sectors;
4083	}
4084
4085	/* Check for any reshape request unless new raid set */
4086	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
4087		/* Initiate a reshape. */
4088		rs_set_rdev_sectors(rs);
4089		mddev_lock_nointr(mddev);
4090		r = rs_start_reshape(rs);
4091		mddev_unlock(mddev);
4092		if (r)
4093			DMWARN("Failed to check/start reshape, continuing without change");
4094		r = 0;
4095	}
4096
4097	return r;
4098}
4099
4100static void raid_resume(struct dm_target *ti)
4101{
4102	struct raid_set *rs = ti->private;
4103	struct mddev *mddev = &rs->md;
4104
4105	if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
4106		/*
4107		 * A secondary resume while the device is active.
4108		 * Take this opportunity to check whether any failed
4109		 * devices are reachable again.
4110		 */
4111		mddev_lock_nointr(mddev);
4112		attempt_restore_of_faulty_devices(rs);
4113		mddev_unlock(mddev);
4114	}
4115
4116	if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
4117		/* Only reduce raid set size before running a disk removing reshape. */
4118		if (mddev->delta_disks < 0)
4119			rs_set_capacity(rs);
4120
4121		mddev_lock_nointr(mddev);
4122		WARN_ON_ONCE(!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery));
4123		WARN_ON_ONCE(rcu_dereference_protected(mddev->sync_thread,
4124						       lockdep_is_held(&mddev->reconfig_mutex)));
4125		clear_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags);
4126		mddev->ro = 0;
4127		mddev->in_sync = 0;
4128		md_unfrozen_sync_thread(mddev);
4129		mddev_unlock_and_resume(mddev);
4130	}
4131}
4132
4133static struct target_type raid_target = {
4134	.name = "raid",
4135	.version = {1, 15, 1},
4136	.module = THIS_MODULE,
4137	.ctr = raid_ctr,
4138	.dtr = raid_dtr,
4139	.map = raid_map,
4140	.status = raid_status,
4141	.message = raid_message,
4142	.iterate_devices = raid_iterate_devices,
4143	.io_hints = raid_io_hints,
4144	.presuspend = raid_presuspend,
4145	.presuspend_undo = raid_presuspend_undo,
4146	.postsuspend = raid_postsuspend,
4147	.preresume = raid_preresume,
4148	.resume = raid_resume,
4149};
4150module_dm(raid);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4151
4152module_param(devices_handle_discard_safely, bool, 0644);
4153MODULE_PARM_DESC(devices_handle_discard_safely,
4154		 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
4155
4156MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
4157MODULE_ALIAS("dm-raid0");
4158MODULE_ALIAS("dm-raid1");
4159MODULE_ALIAS("dm-raid10");
4160MODULE_ALIAS("dm-raid4");
4161MODULE_ALIAS("dm-raid5");
4162MODULE_ALIAS("dm-raid6");
4163MODULE_AUTHOR("Neil Brown <dm-devel@lists.linux.dev>");
4164MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@lists.linux.dev>");
4165MODULE_LICENSE("GPL");