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v6.8
   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
 217/* Array elements of 64 bit needed for rebuild/failed disk bits */
 218#define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
 219
 220/*
 221 * raid set level, layout and chunk sectors backup/restore
 222 */
 223struct rs_layout {
 224	int new_level;
 225	int new_layout;
 226	int new_chunk_sectors;
 227};
 228
 229struct raid_set {
 230	struct dm_target *ti;
 231
 
 232	uint32_t stripe_cache_entries;
 233	unsigned long ctr_flags;
 234	unsigned long runtime_flags;
 235
 236	uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
 237
 238	int raid_disks;
 239	int delta_disks;
 240	int data_offset;
 241	int raid10_copies;
 242	int requested_bitmap_chunk_sectors;
 243
 244	struct mddev md;
 245	struct raid_type *raid_type;
 
 246
 247	sector_t array_sectors;
 248	sector_t dev_sectors;
 249
 250	/* Optional raid4/5/6 journal device */
 251	struct journal_dev {
 252		struct dm_dev *dev;
 253		struct md_rdev rdev;
 254		int mode;
 255	} journal_dev;
 256
 257	struct raid_dev dev[] __counted_by(raid_disks);
 258};
 259
 260static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)
 261{
 262	struct mddev *mddev = &rs->md;
 263
 264	l->new_level = mddev->new_level;
 265	l->new_layout = mddev->new_layout;
 266	l->new_chunk_sectors = mddev->new_chunk_sectors;
 267}
 268
 269static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)
 270{
 271	struct mddev *mddev = &rs->md;
 272
 273	mddev->new_level = l->new_level;
 274	mddev->new_layout = l->new_layout;
 275	mddev->new_chunk_sectors = l->new_chunk_sectors;
 276}
 277
 278/* raid10 algorithms (i.e. formats) */
 279#define	ALGORITHM_RAID10_DEFAULT	0
 280#define	ALGORITHM_RAID10_NEAR		1
 281#define	ALGORITHM_RAID10_OFFSET		2
 282#define	ALGORITHM_RAID10_FAR		3
 283
 284/* Supported raid types and properties. */
 285static struct raid_type {
 286	const char *name;		/* RAID algorithm. */
 287	const char *descr;		/* Descriptor text for logging. */
 288	const unsigned int parity_devs;	/* # of parity devices. */
 289	const unsigned int minimal_devs;/* minimal # of devices in set. */
 290	const unsigned int level;	/* RAID level. */
 291	const unsigned int algorithm;	/* RAID algorithm. */
 292} raid_types[] = {
 293	{"raid0",	  "raid0 (striping)",			    0, 2, 0,  0 /* NONE */},
 294	{"raid1",	  "raid1 (mirroring)",			    0, 2, 1,  0 /* NONE */},
 295	{"raid10_far",	  "raid10 far (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_FAR},
 296	{"raid10_offset", "raid10 offset (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_OFFSET},
 297	{"raid10_near",	  "raid10 near (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_NEAR},
 298	{"raid10",	  "raid10 (striped mirrors)",		    0, 2, 10, ALGORITHM_RAID10_DEFAULT},
 299	{"raid4",	  "raid4 (dedicated first parity disk)",    1, 2, 5,  ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */
 300	{"raid5_n",	  "raid5 (dedicated last parity disk)",	    1, 2, 5,  ALGORITHM_PARITY_N},
 301	{"raid5_ls",	  "raid5 (left symmetric)",		    1, 2, 5,  ALGORITHM_LEFT_SYMMETRIC},
 302	{"raid5_rs",	  "raid5 (right symmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_SYMMETRIC},
 303	{"raid5_la",	  "raid5 (left asymmetric)",		    1, 2, 5,  ALGORITHM_LEFT_ASYMMETRIC},
 304	{"raid5_ra",	  "raid5 (right asymmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_ASYMMETRIC},
 305	{"raid6_zr",	  "raid6 (zero restart)",		    2, 4, 6,  ALGORITHM_ROTATING_ZERO_RESTART},
 306	{"raid6_nr",	  "raid6 (N restart)",			    2, 4, 6,  ALGORITHM_ROTATING_N_RESTART},
 307	{"raid6_nc",	  "raid6 (N continue)",			    2, 4, 6,  ALGORITHM_ROTATING_N_CONTINUE},
 308	{"raid6_n_6",	  "raid6 (dedicated parity/Q n/6)",	    2, 4, 6,  ALGORITHM_PARITY_N_6},
 309	{"raid6_ls_6",	  "raid6 (left symmetric dedicated Q 6)",   2, 4, 6,  ALGORITHM_LEFT_SYMMETRIC_6},
 310	{"raid6_rs_6",	  "raid6 (right symmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_RIGHT_SYMMETRIC_6},
 311	{"raid6_la_6",	  "raid6 (left asymmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_LEFT_ASYMMETRIC_6},
 312	{"raid6_ra_6",	  "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6,  ALGORITHM_RIGHT_ASYMMETRIC_6}
 313};
 314
 315/* True, if @v is in inclusive range [@min, @max] */
 316static bool __within_range(long v, long min, long max)
 317{
 318	return v >= min && v <= max;
 319}
 320
 321/* All table line arguments are defined here */
 322static struct arg_name_flag {
 323	const unsigned long flag;
 324	const char *name;
 325} __arg_name_flags[] = {
 326	{ CTR_FLAG_SYNC, "sync"},
 327	{ CTR_FLAG_NOSYNC, "nosync"},
 328	{ CTR_FLAG_REBUILD, "rebuild"},
 329	{ CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
 330	{ CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
 331	{ CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
 332	{ CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
 333	{ CTR_FLAG_WRITE_MOSTLY, "write_mostly"},
 334	{ CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
 335	{ CTR_FLAG_REGION_SIZE, "region_size"},
 336	{ CTR_FLAG_RAID10_COPIES, "raid10_copies"},
 337	{ CTR_FLAG_RAID10_FORMAT, "raid10_format"},
 338	{ CTR_FLAG_DATA_OFFSET, "data_offset"},
 339	{ CTR_FLAG_DELTA_DISKS, "delta_disks"},
 340	{ CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
 341	{ CTR_FLAG_JOURNAL_DEV, "journal_dev" },
 342	{ CTR_FLAG_JOURNAL_MODE, "journal_mode" },
 343};
 344
 345/* Return argument name string for given @flag */
 346static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
 347{
 348	if (hweight32(flag) == 1) {
 349		struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
 350
 351		while (anf-- > __arg_name_flags)
 352			if (flag & anf->flag)
 353				return anf->name;
 354
 355	} else
 356		DMERR("%s called with more than one flag!", __func__);
 357
 358	return NULL;
 359}
 360
 361/* Define correlation of raid456 journal cache modes and dm-raid target line parameters */
 362static struct {
 363	const int mode;
 364	const char *param;
 365} _raid456_journal_mode[] = {
 366	{ R5C_JOURNAL_MODE_WRITE_THROUGH, "writethrough" },
 367	{ R5C_JOURNAL_MODE_WRITE_BACK,    "writeback" }
 368};
 369
 370/* Return MD raid4/5/6 journal mode for dm @journal_mode one */
 371static int dm_raid_journal_mode_to_md(const char *mode)
 372{
 373	int m = ARRAY_SIZE(_raid456_journal_mode);
 374
 375	while (m--)
 376		if (!strcasecmp(mode, _raid456_journal_mode[m].param))
 377			return _raid456_journal_mode[m].mode;
 378
 379	return -EINVAL;
 380}
 381
 382/* Return dm-raid raid4/5/6 journal mode string for @mode */
 383static const char *md_journal_mode_to_dm_raid(const int mode)
 384{
 385	int m = ARRAY_SIZE(_raid456_journal_mode);
 386
 387	while (m--)
 388		if (mode == _raid456_journal_mode[m].mode)
 389			return _raid456_journal_mode[m].param;
 390
 391	return "unknown";
 392}
 393
 394/*
 395 * Bool helpers to test for various raid levels of a raid set.
 396 * It's level as reported by the superblock rather than
 397 * the requested raid_type passed to the constructor.
 398 */
 399/* Return true, if raid set in @rs is raid0 */
 400static bool rs_is_raid0(struct raid_set *rs)
 401{
 402	return !rs->md.level;
 403}
 404
 405/* Return true, if raid set in @rs is raid1 */
 406static bool rs_is_raid1(struct raid_set *rs)
 407{
 408	return rs->md.level == 1;
 409}
 410
 411/* Return true, if raid set in @rs is raid10 */
 412static bool rs_is_raid10(struct raid_set *rs)
 413{
 414	return rs->md.level == 10;
 415}
 416
 417/* Return true, if raid set in @rs is level 6 */
 418static bool rs_is_raid6(struct raid_set *rs)
 419{
 420	return rs->md.level == 6;
 421}
 422
 423/* Return true, if raid set in @rs is level 4, 5 or 6 */
 424static bool rs_is_raid456(struct raid_set *rs)
 425{
 426	return __within_range(rs->md.level, 4, 6);
 427}
 428
 429/* Return true, if raid set in @rs is reshapable */
 430static bool __is_raid10_far(int layout);
 431static bool rs_is_reshapable(struct raid_set *rs)
 432{
 433	return rs_is_raid456(rs) ||
 434	       (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
 435}
 436
 437/* Return true, if raid set in @rs is recovering */
 438static bool rs_is_recovering(struct raid_set *rs)
 439{
 440	return rs->md.recovery_cp < rs->md.dev_sectors;
 441}
 442
 443/* Return true, if raid set in @rs is reshaping */
 444static bool rs_is_reshaping(struct raid_set *rs)
 445{
 446	return rs->md.reshape_position != MaxSector;
 447}
 448
 449/*
 450 * bool helpers to test for various raid levels of a raid type @rt
 451 */
 452
 453/* Return true, if raid type in @rt is raid0 */
 454static bool rt_is_raid0(struct raid_type *rt)
 455{
 456	return !rt->level;
 457}
 458
 459/* Return true, if raid type in @rt is raid1 */
 460static bool rt_is_raid1(struct raid_type *rt)
 461{
 462	return rt->level == 1;
 463}
 464
 465/* Return true, if raid type in @rt is raid10 */
 466static bool rt_is_raid10(struct raid_type *rt)
 467{
 468	return rt->level == 10;
 469}
 470
 471/* Return true, if raid type in @rt is raid4/5 */
 472static bool rt_is_raid45(struct raid_type *rt)
 473{
 474	return __within_range(rt->level, 4, 5);
 475}
 476
 477/* Return true, if raid type in @rt is raid6 */
 478static bool rt_is_raid6(struct raid_type *rt)
 479{
 480	return rt->level == 6;
 481}
 482
 483/* Return true, if raid type in @rt is raid4/5/6 */
 484static bool rt_is_raid456(struct raid_type *rt)
 485{
 486	return __within_range(rt->level, 4, 6);
 487}
 488/* END: raid level bools */
 489
 490/* Return valid ctr flags for the raid level of @rs */
 491static unsigned long __valid_flags(struct raid_set *rs)
 492{
 493	if (rt_is_raid0(rs->raid_type))
 494		return RAID0_VALID_FLAGS;
 495	else if (rt_is_raid1(rs->raid_type))
 496		return RAID1_VALID_FLAGS;
 497	else if (rt_is_raid10(rs->raid_type))
 498		return RAID10_VALID_FLAGS;
 499	else if (rt_is_raid45(rs->raid_type))
 500		return RAID45_VALID_FLAGS;
 501	else if (rt_is_raid6(rs->raid_type))
 502		return RAID6_VALID_FLAGS;
 503
 504	return 0;
 505}
 506
 507/*
 508 * Check for valid flags set on @rs
 509 *
 510 * Has to be called after parsing of the ctr flags!
 511 */
 512static int rs_check_for_valid_flags(struct raid_set *rs)
 513{
 514	if (rs->ctr_flags & ~__valid_flags(rs)) {
 515		rs->ti->error = "Invalid flags combination";
 516		return -EINVAL;
 517	}
 518
 519	return 0;
 520}
 521
 522/* MD raid10 bit definitions and helpers */
 523#define RAID10_OFFSET			(1 << 16) /* stripes with data copies area adjacent on devices */
 524#define RAID10_BROCKEN_USE_FAR_SETS	(1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
 525#define RAID10_USE_FAR_SETS		(1 << 18) /* Use sets instead of whole stripe rotation */
 526#define RAID10_FAR_COPIES_SHIFT		8	  /* raid10 # far copies shift (2nd byte of layout) */
 527
 528/* Return md raid10 near copies for @layout */
 529static unsigned int __raid10_near_copies(int layout)
 530{
 531	return layout & 0xFF;
 532}
 533
 534/* Return md raid10 far copies for @layout */
 535static unsigned int __raid10_far_copies(int layout)
 536{
 537	return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
 538}
 539
 540/* Return true if md raid10 offset for @layout */
 541static bool __is_raid10_offset(int layout)
 542{
 543	return !!(layout & RAID10_OFFSET);
 544}
 545
 546/* Return true if md raid10 near for @layout */
 547static bool __is_raid10_near(int layout)
 548{
 549	return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
 550}
 551
 552/* Return true if md raid10 far for @layout */
 553static bool __is_raid10_far(int layout)
 554{
 555	return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
 556}
 557
 558/* Return md raid10 layout string for @layout */
 559static const char *raid10_md_layout_to_format(int layout)
 560{
 561	/*
 562	 * Bit 16 stands for "offset"
 563	 * (i.e. adjacent stripes hold copies)
 564	 *
 565	 * Refer to MD's raid10.c for details
 566	 */
 567	if (__is_raid10_offset(layout))
 568		return "offset";
 569
 570	if (__raid10_near_copies(layout) > 1)
 571		return "near";
 572
 573	if (__raid10_far_copies(layout) > 1)
 574		return "far";
 575
 576	return "unknown";
 577}
 578
 579/* Return md raid10 algorithm for @name */
 580static int raid10_name_to_format(const char *name)
 581{
 582	if (!strcasecmp(name, "near"))
 583		return ALGORITHM_RAID10_NEAR;
 584	else if (!strcasecmp(name, "offset"))
 585		return ALGORITHM_RAID10_OFFSET;
 586	else if (!strcasecmp(name, "far"))
 587		return ALGORITHM_RAID10_FAR;
 588
 589	return -EINVAL;
 590}
 591
 592/* Return md raid10 copies for @layout */
 593static unsigned int raid10_md_layout_to_copies(int layout)
 594{
 595	return max(__raid10_near_copies(layout), __raid10_far_copies(layout));
 596}
 597
 598/* Return md raid10 format id for @format string */
 599static int raid10_format_to_md_layout(struct raid_set *rs,
 600				      unsigned int algorithm,
 601				      unsigned int copies)
 602{
 603	unsigned int n = 1, f = 1, r = 0;
 604
 605	/*
 606	 * MD resilienece flaw:
 607	 *
 608	 * enabling use_far_sets for far/offset formats causes copies
 609	 * to be colocated on the same devs together with their origins!
 610	 *
 611	 * -> disable it for now in the definition above
 612	 */
 613	if (algorithm == ALGORITHM_RAID10_DEFAULT ||
 614	    algorithm == ALGORITHM_RAID10_NEAR)
 615		n = copies;
 616
 617	else if (algorithm == ALGORITHM_RAID10_OFFSET) {
 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 if (algorithm == ALGORITHM_RAID10_FAR) {
 624		f = copies;
 
 625		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 626			r |= RAID10_USE_FAR_SETS;
 627
 628	} else
 629		return -EINVAL;
 630
 631	return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
 632}
 633/* END: MD raid10 bit definitions and helpers */
 634
 635/* Check for any of the raid10 algorithms */
 636static bool __got_raid10(struct raid_type *rtp, const int layout)
 637{
 638	if (rtp->level == 10) {
 639		switch (rtp->algorithm) {
 640		case ALGORITHM_RAID10_DEFAULT:
 641		case ALGORITHM_RAID10_NEAR:
 642			return __is_raid10_near(layout);
 643		case ALGORITHM_RAID10_OFFSET:
 644			return __is_raid10_offset(layout);
 645		case ALGORITHM_RAID10_FAR:
 646			return __is_raid10_far(layout);
 647		default:
 648			break;
 649		}
 650	}
 651
 652	return false;
 653}
 654
 655/* Return raid_type for @name */
 656static struct raid_type *get_raid_type(const char *name)
 657{
 658	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 659
 660	while (rtp-- > raid_types)
 661		if (!strcasecmp(rtp->name, name))
 662			return rtp;
 663
 664	return NULL;
 665}
 666
 667/* Return raid_type for @name based derived from @level and @layout */
 668static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
 669{
 670	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 671
 672	while (rtp-- > raid_types) {
 673		/* RAID10 special checks based on @layout flags/properties */
 674		if (rtp->level == level &&
 675		    (__got_raid10(rtp, layout) || rtp->algorithm == layout))
 676			return rtp;
 677	}
 678
 679	return NULL;
 680}
 681
 682/* Adjust rdev sectors */
 683static void rs_set_rdev_sectors(struct raid_set *rs)
 
 
 
 684{
 685	struct mddev *mddev = &rs->md;
 686	struct md_rdev *rdev;
 
 687
 688	/*
 689	 * raid10 sets rdev->sector to the device size, which
 690	 * is unintended in case of out-of-place reshaping
 691	 */
 692	rdev_for_each(rdev, mddev)
 693		if (!test_bit(Journal, &rdev->flags))
 694			rdev->sectors = mddev->dev_sectors;
 695}
 696
 697/*
 698 * Change bdev capacity of @rs in case of a disk add/remove reshape
 699 */
 700static void rs_set_capacity(struct raid_set *rs)
 701{
 702	struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
 703
 704	set_capacity_and_notify(gendisk, rs->md.array_sectors);
 705}
 706
 707/*
 708 * Set the mddev properties in @rs to the current
 709 * ones retrieved from the freshest superblock
 710 */
 711static void rs_set_cur(struct raid_set *rs)
 712{
 713	struct mddev *mddev = &rs->md;
 714
 715	mddev->new_level = mddev->level;
 716	mddev->new_layout = mddev->layout;
 717	mddev->new_chunk_sectors = mddev->chunk_sectors;
 718}
 719
 720/*
 721 * Set the mddev properties in @rs to the new
 722 * ones requested by the ctr
 723 */
 724static void rs_set_new(struct raid_set *rs)
 725{
 726	struct mddev *mddev = &rs->md;
 727
 728	mddev->level = mddev->new_level;
 729	mddev->layout = mddev->new_layout;
 730	mddev->chunk_sectors = mddev->new_chunk_sectors;
 731	mddev->raid_disks = rs->raid_disks;
 732	mddev->delta_disks = 0;
 733}
 734
 735static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
 736				       unsigned int raid_devs)
 737{
 738	unsigned int i;
 739	struct raid_set *rs;
 740
 741	if (raid_devs <= raid_type->parity_devs) {
 742		ti->error = "Insufficient number of devices";
 743		return ERR_PTR(-EINVAL);
 744	}
 745
 746	rs = kzalloc(struct_size(rs, dev, raid_devs), GFP_KERNEL);
 747	if (!rs) {
 748		ti->error = "Cannot allocate raid context";
 749		return ERR_PTR(-ENOMEM);
 750	}
 751
 752	if (mddev_init(&rs->md)) {
 753		kfree(rs);
 754		ti->error = "Cannot initialize raid context";
 755		return ERR_PTR(-ENOMEM);
 756	}
 757
 758	rs->raid_disks = raid_devs;
 759	rs->delta_disks = 0;
 760
 761	rs->ti = ti;
 762	rs->raid_type = raid_type;
 763	rs->stripe_cache_entries = 256;
 764	rs->md.raid_disks = raid_devs;
 765	rs->md.level = raid_type->level;
 766	rs->md.new_level = rs->md.level;
 767	rs->md.layout = raid_type->algorithm;
 768	rs->md.new_layout = rs->md.layout;
 769	rs->md.delta_disks = 0;
 770	rs->md.recovery_cp = MaxSector;
 771
 772	for (i = 0; i < raid_devs; i++)
 773		md_rdev_init(&rs->dev[i].rdev);
 774
 775	/*
 776	 * Remaining items to be initialized by further RAID params:
 777	 *  rs->md.persistent
 778	 *  rs->md.external
 779	 *  rs->md.chunk_sectors
 780	 *  rs->md.new_chunk_sectors
 781	 *  rs->md.dev_sectors
 782	 */
 783
 784	return rs;
 785}
 786
 787/* Free all @rs allocations */
 788static void raid_set_free(struct raid_set *rs)
 789{
 790	int i;
 791
 792	if (rs->journal_dev.dev) {
 793		md_rdev_clear(&rs->journal_dev.rdev);
 794		dm_put_device(rs->ti, rs->journal_dev.dev);
 795	}
 796
 797	for (i = 0; i < rs->raid_disks; i++) {
 798		if (rs->dev[i].meta_dev)
 799			dm_put_device(rs->ti, rs->dev[i].meta_dev);
 800		md_rdev_clear(&rs->dev[i].rdev);
 801		if (rs->dev[i].data_dev)
 802			dm_put_device(rs->ti, rs->dev[i].data_dev);
 803	}
 804
 805	mddev_destroy(&rs->md);
 806	kfree(rs);
 807}
 808
 809/*
 810 * For every device we have two words
 811 *  <meta_dev>: meta device name or '-' if missing
 812 *  <data_dev>: data device name or '-' if missing
 813 *
 814 * The following are permitted:
 815 *    - -
 816 *    - <data_dev>
 817 *    <meta_dev> <data_dev>
 818 *
 819 * The following is not allowed:
 820 *    <meta_dev> -
 821 *
 822 * This code parses those words.  If there is a failure,
 823 * the caller must use raid_set_free() to unwind the operations.
 824 */
 825static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
 826{
 827	int i;
 828	int rebuild = 0;
 829	int metadata_available = 0;
 830	int r = 0;
 831	const char *arg;
 832
 833	/* Put off the number of raid devices argument to get to dev pairs */
 834	arg = dm_shift_arg(as);
 835	if (!arg)
 836		return -EINVAL;
 837
 838	for (i = 0; i < rs->raid_disks; i++) {
 839		rs->dev[i].rdev.raid_disk = i;
 840
 841		rs->dev[i].meta_dev = NULL;
 842		rs->dev[i].data_dev = NULL;
 843
 844		/*
 845		 * There are no offsets initially.
 846		 * Out of place reshape will set them accordingly.
 847		 */
 848		rs->dev[i].rdev.data_offset = 0;
 849		rs->dev[i].rdev.new_data_offset = 0;
 850		rs->dev[i].rdev.mddev = &rs->md;
 851
 852		arg = dm_shift_arg(as);
 853		if (!arg)
 854			return -EINVAL;
 855
 856		if (strcmp(arg, "-")) {
 857			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 858					  &rs->dev[i].meta_dev);
 859			if (r) {
 860				rs->ti->error = "RAID metadata device lookup failure";
 861				return r;
 862			}
 863
 864			rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
 865			if (!rs->dev[i].rdev.sb_page) {
 866				rs->ti->error = "Failed to allocate superblock page";
 867				return -ENOMEM;
 868			}
 869		}
 870
 871		arg = dm_shift_arg(as);
 872		if (!arg)
 873			return -EINVAL;
 874
 875		if (!strcmp(arg, "-")) {
 876			if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
 877			    (!rs->dev[i].rdev.recovery_offset)) {
 878				rs->ti->error = "Drive designated for rebuild not specified";
 879				return -EINVAL;
 880			}
 881
 882			if (rs->dev[i].meta_dev) {
 883				rs->ti->error = "No data device supplied with metadata device";
 884				return -EINVAL;
 885			}
 886
 887			continue;
 888		}
 889
 890		r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 891				  &rs->dev[i].data_dev);
 892		if (r) {
 893			rs->ti->error = "RAID device lookup failure";
 894			return r;
 895		}
 896
 897		if (rs->dev[i].meta_dev) {
 898			metadata_available = 1;
 899			rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
 900		}
 901		rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
 902		list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
 903		if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
 904			rebuild++;
 905	}
 906
 907	if (rs->journal_dev.dev)
 908		list_add_tail(&rs->journal_dev.rdev.same_set, &rs->md.disks);
 909
 910	if (metadata_available) {
 911		rs->md.external = 0;
 912		rs->md.persistent = 1;
 913		rs->md.major_version = 2;
 914	} else if (rebuild && !rs->md.recovery_cp) {
 915		/*
 916		 * Without metadata, we will not be able to tell if the array
 917		 * is in-sync or not - we must assume it is not.  Therefore,
 918		 * it is impossible to rebuild a drive.
 919		 *
 920		 * Even if there is metadata, the on-disk information may
 921		 * indicate that the array is not in-sync and it will then
 922		 * fail at that time.
 923		 *
 924		 * User could specify 'nosync' option if desperate.
 925		 */
 926		rs->ti->error = "Unable to rebuild drive while array is not in-sync";
 927		return -EINVAL;
 928	}
 929
 930	return 0;
 931}
 932
 933/*
 934 * validate_region_size
 935 * @rs
 936 * @region_size:  region size in sectors.  If 0, pick a size (4MiB default).
 937 *
 938 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
 939 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
 940 *
 941 * Returns: 0 on success, -EINVAL on failure.
 942 */
 943static int validate_region_size(struct raid_set *rs, unsigned long region_size)
 944{
 945	unsigned long min_region_size = rs->ti->len / (1 << 21);
 946
 947	if (rs_is_raid0(rs))
 948		return 0;
 949
 950	if (!region_size) {
 951		/*
 952		 * Choose a reasonable default.	 All figures in sectors.
 953		 */
 954		if (min_region_size > (1 << 13)) {
 955			/* If not a power of 2, make it the next power of 2 */
 956			region_size = roundup_pow_of_two(min_region_size);
 957			DMINFO("Choosing default region size of %lu sectors",
 958			       region_size);
 959		} else {
 960			DMINFO("Choosing default region size of 4MiB");
 961			region_size = 1 << 13; /* sectors */
 962		}
 963	} else {
 964		/*
 965		 * Validate user-supplied value.
 966		 */
 967		if (region_size > rs->ti->len) {
 968			rs->ti->error = "Supplied region size is too large";
 969			return -EINVAL;
 970		}
 971
 972		if (region_size < min_region_size) {
 973			DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
 974			      region_size, min_region_size);
 975			rs->ti->error = "Supplied region size is too small";
 976			return -EINVAL;
 977		}
 978
 979		if (!is_power_of_2(region_size)) {
 980			rs->ti->error = "Region size is not a power of 2";
 981			return -EINVAL;
 982		}
 983
 984		if (region_size < rs->md.chunk_sectors) {
 985			rs->ti->error = "Region size is smaller than the chunk size";
 986			return -EINVAL;
 987		}
 988	}
 989
 990	/*
 991	 * Convert sectors to bytes.
 992	 */
 993	rs->md.bitmap_info.chunksize = to_bytes(region_size);
 994
 995	return 0;
 996}
 997
 998/*
 999 * validate_raid_redundancy
1000 * @rs
1001 *
1002 * Determine if there are enough devices in the array that haven't
1003 * failed (or are being rebuilt) to form a usable array.
1004 *
1005 * Returns: 0 on success, -EINVAL on failure.
1006 */
1007static int validate_raid_redundancy(struct raid_set *rs)
1008{
1009	unsigned int i, rebuild_cnt = 0;
1010	unsigned int rebuilds_per_group = 0, copies, raid_disks;
1011	unsigned int group_size, last_group_start;
1012
1013	for (i = 0; i < rs->raid_disks; i++)
1014		if (!test_bit(FirstUse, &rs->dev[i].rdev.flags) &&
1015		    ((!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
1016		      !rs->dev[i].rdev.sb_page)))
1017			rebuild_cnt++;
1018
1019	switch (rs->md.level) {
1020	case 0:
1021		break;
1022	case 1:
1023		if (rebuild_cnt >= rs->md.raid_disks)
1024			goto too_many;
1025		break;
1026	case 4:
1027	case 5:
1028	case 6:
1029		if (rebuild_cnt > rs->raid_type->parity_devs)
1030			goto too_many;
1031		break;
1032	case 10:
1033		copies = raid10_md_layout_to_copies(rs->md.new_layout);
1034		if (copies < 2) {
1035			DMERR("Bogus raid10 data copies < 2!");
1036			return -EINVAL;
1037		}
1038
1039		if (rebuild_cnt < copies)
1040			break;
1041
1042		/*
1043		 * It is possible to have a higher rebuild count for RAID10,
1044		 * as long as the failed devices occur in different mirror
1045		 * groups (i.e. different stripes).
1046		 *
1047		 * When checking "near" format, make sure no adjacent devices
1048		 * have failed beyond what can be handled.  In addition to the
1049		 * simple case where the number of devices is a multiple of the
1050		 * number of copies, we must also handle cases where the number
1051		 * of devices is not a multiple of the number of copies.
1052		 * E.g.	   dev1 dev2 dev3 dev4 dev5
1053		 *	    A	 A    B	   B	C
1054		 *	    C	 D    D	   E	E
1055		 */
1056		raid_disks = min(rs->raid_disks, rs->md.raid_disks);
1057		if (__is_raid10_near(rs->md.new_layout)) {
1058			for (i = 0; i < raid_disks; i++) {
1059				if (!(i % copies))
1060					rebuilds_per_group = 0;
1061				if ((!rs->dev[i].rdev.sb_page ||
1062				    !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1063				    (++rebuilds_per_group >= copies))
1064					goto too_many;
1065			}
1066			break;
1067		}
1068
1069		/*
1070		 * When checking "far" and "offset" formats, we need to ensure
1071		 * that the device that holds its copy is not also dead or
1072		 * being rebuilt.  (Note that "far" and "offset" formats only
1073		 * support two copies right now.  These formats also only ever
1074		 * use the 'use_far_sets' variant.)
1075		 *
1076		 * This check is somewhat complicated by the need to account
1077		 * for arrays that are not a multiple of (far) copies.	This
1078		 * results in the need to treat the last (potentially larger)
1079		 * set differently.
1080		 */
1081		group_size = (raid_disks / copies);
1082		last_group_start = (raid_disks / group_size) - 1;
1083		last_group_start *= group_size;
1084		for (i = 0; i < raid_disks; i++) {
1085			if (!(i % copies) && !(i > last_group_start))
1086				rebuilds_per_group = 0;
1087			if ((!rs->dev[i].rdev.sb_page ||
1088			     !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1089			    (++rebuilds_per_group >= copies))
1090				goto too_many;
1091		}
1092		break;
1093	default:
1094		if (rebuild_cnt)
1095			return -EINVAL;
1096	}
1097
1098	return 0;
1099
1100too_many:
1101	return -EINVAL;
1102}
1103
1104/*
1105 * Possible arguments are...
1106 *	<chunk_size> [optional_args]
1107 *
1108 * Argument definitions
1109 *    <chunk_size>			The number of sectors per disk that
1110 *					will form the "stripe"
1111 *    [[no]sync]			Force or prevent recovery of the
1112 *					entire array
1113 *    [rebuild <idx>]			Rebuild the drive indicated by the index
1114 *    [daemon_sleep <ms>]		Time between bitmap daemon work to
1115 *					clear bits
1116 *    [min_recovery_rate <kB/sec/disk>]	Throttle RAID initialization
1117 *    [max_recovery_rate <kB/sec/disk>]	Throttle RAID initialization
1118 *    [write_mostly <idx>]		Indicate a write mostly drive via index
1119 *    [max_write_behind <sectors>]	See '-write-behind=' (man mdadm)
1120 *    [stripe_cache <sectors>]		Stripe cache size for higher RAIDs
1121 *    [region_size <sectors>]		Defines granularity of bitmap
1122 *    [journal_dev <dev>]		raid4/5/6 journaling deviice
1123 *					(i.e. write hole closing log)
1124 *
1125 * RAID10-only options:
1126 *    [raid10_copies <# copies>]	Number of copies.  (Default: 2)
1127 *    [raid10_format <near|far|offset>] Layout algorithm.  (Default: near)
1128 */
1129static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
1130			     unsigned int num_raid_params)
1131{
1132	int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
1133	unsigned int raid10_copies = 2;
1134	unsigned int i, write_mostly = 0;
1135	unsigned int region_size = 0;
1136	sector_t max_io_len;
1137	const char *arg, *key;
1138	struct raid_dev *rd;
1139	struct raid_type *rt = rs->raid_type;
1140
1141	arg = dm_shift_arg(as);
1142	num_raid_params--; /* Account for chunk_size argument */
1143
1144	if (kstrtoint(arg, 10, &value) < 0) {
1145		rs->ti->error = "Bad numerical argument given for chunk_size";
1146		return -EINVAL;
1147	}
1148
1149	/*
1150	 * First, parse the in-order required arguments
1151	 * "chunk_size" is the only argument of this type.
1152	 */
1153	if (rt_is_raid1(rt)) {
1154		if (value)
1155			DMERR("Ignoring chunk size parameter for RAID 1");
1156		value = 0;
1157	} else if (!is_power_of_2(value)) {
1158		rs->ti->error = "Chunk size must be a power of 2";
1159		return -EINVAL;
1160	} else if (value < 8) {
1161		rs->ti->error = "Chunk size value is too small";
1162		return -EINVAL;
1163	}
1164
1165	rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1166
1167	/*
1168	 * We set each individual device as In_sync with a completed
1169	 * 'recovery_offset'.  If there has been a device failure or
1170	 * replacement then one of the following cases applies:
1171	 *
1172	 *   1) User specifies 'rebuild'.
1173	 *	- Device is reset when param is read.
1174	 *   2) A new device is supplied.
1175	 *	- No matching superblock found, resets device.
1176	 *   3) Device failure was transient and returns on reload.
1177	 *	- Failure noticed, resets device for bitmap replay.
1178	 *   4) Device hadn't completed recovery after previous failure.
1179	 *	- Superblock is read and overrides recovery_offset.
1180	 *
1181	 * What is found in the superblocks of the devices is always
1182	 * authoritative, unless 'rebuild' or '[no]sync' was specified.
1183	 */
1184	for (i = 0; i < rs->raid_disks; i++) {
1185		set_bit(In_sync, &rs->dev[i].rdev.flags);
1186		rs->dev[i].rdev.recovery_offset = MaxSector;
1187	}
1188
1189	/*
1190	 * Second, parse the unordered optional arguments
1191	 */
1192	for (i = 0; i < num_raid_params; i++) {
1193		key = dm_shift_arg(as);
1194		if (!key) {
1195			rs->ti->error = "Not enough raid parameters given";
1196			return -EINVAL;
1197		}
1198
1199		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1200			if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1201				rs->ti->error = "Only one 'nosync' argument allowed";
1202				return -EINVAL;
1203			}
1204			continue;
1205		}
1206		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1207			if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1208				rs->ti->error = "Only one 'sync' argument allowed";
1209				return -EINVAL;
1210			}
1211			continue;
1212		}
1213		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1214			if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1215				rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1216				return -EINVAL;
1217			}
1218			continue;
1219		}
1220
1221		arg = dm_shift_arg(as);
1222		i++; /* Account for the argument pairs */
1223		if (!arg) {
1224			rs->ti->error = "Wrong number of raid parameters given";
1225			return -EINVAL;
1226		}
1227
1228		/*
1229		 * Parameters that take a string value are checked here.
1230		 */
1231		/* "raid10_format {near|offset|far} */
1232		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1233			if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1234				rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1235				return -EINVAL;
1236			}
1237			if (!rt_is_raid10(rt)) {
1238				rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1239				return -EINVAL;
1240			}
1241			raid10_format = raid10_name_to_format(arg);
1242			if (raid10_format < 0) {
1243				rs->ti->error = "Invalid 'raid10_format' value given";
1244				return raid10_format;
1245			}
1246			continue;
1247		}
1248
1249		/* "journal_dev <dev>" */
1250		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV))) {
1251			int r;
1252			struct md_rdev *jdev;
1253
1254			if (test_and_set_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
1255				rs->ti->error = "Only one raid4/5/6 set journaling device allowed";
1256				return -EINVAL;
1257			}
1258			if (!rt_is_raid456(rt)) {
1259				rs->ti->error = "'journal_dev' is an invalid parameter for this RAID type";
1260				return -EINVAL;
1261			}
1262			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
1263					  &rs->journal_dev.dev);
1264			if (r) {
1265				rs->ti->error = "raid4/5/6 journal device lookup failure";
1266				return r;
1267			}
1268			jdev = &rs->journal_dev.rdev;
1269			md_rdev_init(jdev);
1270			jdev->mddev = &rs->md;
1271			jdev->bdev = rs->journal_dev.dev->bdev;
1272			jdev->sectors = bdev_nr_sectors(jdev->bdev);
1273			if (jdev->sectors < MIN_RAID456_JOURNAL_SPACE) {
1274				rs->ti->error = "No space for raid4/5/6 journal";
1275				return -ENOSPC;
1276			}
1277			rs->journal_dev.mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
1278			set_bit(Journal, &jdev->flags);
1279			continue;
1280		}
1281
1282		/* "journal_mode <mode>" ("journal_dev" mandatory!) */
1283		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE))) {
1284			int r;
1285
1286			if (!test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
1287				rs->ti->error = "raid4/5/6 'journal_mode' is invalid without 'journal_dev'";
1288				return -EINVAL;
1289			}
1290			if (test_and_set_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
1291				rs->ti->error = "Only one raid4/5/6 'journal_mode' argument allowed";
1292				return -EINVAL;
1293			}
1294			r = dm_raid_journal_mode_to_md(arg);
1295			if (r < 0) {
1296				rs->ti->error = "Invalid 'journal_mode' argument";
1297				return r;
1298			}
1299			rs->journal_dev.mode = r;
1300			continue;
1301		}
1302
1303		/*
1304		 * Parameters with number values from here on.
1305		 */
1306		if (kstrtoint(arg, 10, &value) < 0) {
1307			rs->ti->error = "Bad numerical argument given in raid params";
1308			return -EINVAL;
1309		}
1310
1311		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1312			/*
1313			 * "rebuild" is being passed in by userspace to provide
1314			 * indexes of replaced devices and to set up additional
1315			 * devices on raid level takeover.
1316			 */
1317			if (!__within_range(value, 0, rs->raid_disks - 1)) {
1318				rs->ti->error = "Invalid rebuild index given";
1319				return -EINVAL;
1320			}
1321
1322			if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1323				rs->ti->error = "rebuild for this index already given";
1324				return -EINVAL;
1325			}
1326
1327			rd = rs->dev + value;
1328			clear_bit(In_sync, &rd->rdev.flags);
1329			clear_bit(Faulty, &rd->rdev.flags);
1330			rd->rdev.recovery_offset = 0;
1331			set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1332		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1333			if (!rt_is_raid1(rt)) {
1334				rs->ti->error = "write_mostly option is only valid for RAID1";
1335				return -EINVAL;
1336			}
1337
1338			if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1339				rs->ti->error = "Invalid write_mostly index given";
1340				return -EINVAL;
1341			}
1342
1343			write_mostly++;
1344			set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1345			set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1346		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1347			if (!rt_is_raid1(rt)) {
1348				rs->ti->error = "max_write_behind option is only valid for RAID1";
1349				return -EINVAL;
1350			}
1351
1352			if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1353				rs->ti->error = "Only one max_write_behind argument pair allowed";
1354				return -EINVAL;
1355			}
1356
1357			/*
1358			 * In device-mapper, we specify things in sectors, but
1359			 * MD records this value in kB
1360			 */
1361			if (value < 0 || value / 2 > COUNTER_MAX) {
 
1362				rs->ti->error = "Max write-behind limit out of range";
1363				return -EINVAL;
1364			}
1365
1366			rs->md.bitmap_info.max_write_behind = value / 2;
1367		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1368			if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1369				rs->ti->error = "Only one daemon_sleep argument pair allowed";
1370				return -EINVAL;
1371			}
1372			if (value < 0) {
1373				rs->ti->error = "daemon sleep period out of range";
1374				return -EINVAL;
1375			}
1376			rs->md.bitmap_info.daemon_sleep = value;
1377		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1378			/* Userspace passes new data_offset after having extended the data image LV */
1379			if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1380				rs->ti->error = "Only one data_offset argument pair allowed";
1381				return -EINVAL;
1382			}
1383			/* Ensure sensible data offset */
1384			if (value < 0 ||
1385			    (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {
1386				rs->ti->error = "Bogus data_offset value";
1387				return -EINVAL;
1388			}
1389			rs->data_offset = value;
1390		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1391			/* Define the +/-# of disks to add to/remove from the given raid set */
1392			if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1393				rs->ti->error = "Only one delta_disks argument pair allowed";
1394				return -EINVAL;
1395			}
1396			/* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1397			if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1398				rs->ti->error = "Too many delta_disk requested";
1399				return -EINVAL;
1400			}
1401
1402			rs->delta_disks = value;
1403		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1404			if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1405				rs->ti->error = "Only one stripe_cache argument pair allowed";
1406				return -EINVAL;
1407			}
1408
1409			if (!rt_is_raid456(rt)) {
1410				rs->ti->error = "Inappropriate argument: stripe_cache";
1411				return -EINVAL;
1412			}
1413
1414			if (value < 0) {
1415				rs->ti->error = "Bogus stripe cache entries value";
1416				return -EINVAL;
1417			}
1418			rs->stripe_cache_entries = value;
1419		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1420			if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1421				rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1422				return -EINVAL;
1423			}
1424
1425			if (value < 0) {
1426				rs->ti->error = "min_recovery_rate out of range";
1427				return -EINVAL;
1428			}
1429			rs->md.sync_speed_min = value;
1430		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1431			if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
1432				rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1433				return -EINVAL;
1434			}
1435
1436			if (value < 0) {
1437				rs->ti->error = "max_recovery_rate out of range";
1438				return -EINVAL;
1439			}
1440			rs->md.sync_speed_max = value;
1441		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1442			if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1443				rs->ti->error = "Only one region_size argument pair allowed";
1444				return -EINVAL;
1445			}
1446
1447			region_size = value;
1448			rs->requested_bitmap_chunk_sectors = value;
1449		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1450			if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1451				rs->ti->error = "Only one raid10_copies argument pair allowed";
1452				return -EINVAL;
1453			}
1454
1455			if (!__within_range(value, 2, rs->md.raid_disks)) {
1456				rs->ti->error = "Bad value for 'raid10_copies'";
1457				return -EINVAL;
1458			}
1459
1460			raid10_copies = value;
1461		} else {
1462			DMERR("Unable to parse RAID parameter: %s", key);
1463			rs->ti->error = "Unable to parse RAID parameter";
1464			return -EINVAL;
1465		}
1466	}
1467
1468	if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1469	    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1470		rs->ti->error = "sync and nosync are mutually exclusive";
1471		return -EINVAL;
1472	}
1473
1474	if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
1475	    (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
1476	     test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
1477		rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
1478		return -EINVAL;
1479	}
1480
1481	if (write_mostly >= rs->md.raid_disks) {
1482		rs->ti->error = "Can't set all raid1 devices to write_mostly";
1483		return -EINVAL;
1484	}
1485
1486	if (rs->md.sync_speed_max &&
1487	    rs->md.sync_speed_min > rs->md.sync_speed_max) {
1488		rs->ti->error = "Bogus recovery rates";
1489		return -EINVAL;
1490	}
1491
1492	if (validate_region_size(rs, region_size))
1493		return -EINVAL;
1494
1495	if (rs->md.chunk_sectors)
1496		max_io_len = rs->md.chunk_sectors;
1497	else
1498		max_io_len = region_size;
1499
1500	if (dm_set_target_max_io_len(rs->ti, max_io_len))
1501		return -EINVAL;
1502
1503	if (rt_is_raid10(rt)) {
1504		if (raid10_copies > rs->md.raid_disks) {
1505			rs->ti->error = "Not enough devices to satisfy specification";
1506			return -EINVAL;
1507		}
1508
1509		rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1510		if (rs->md.new_layout < 0) {
1511			rs->ti->error = "Error getting raid10 format";
1512			return rs->md.new_layout;
1513		}
1514
1515		rt = get_raid_type_by_ll(10, rs->md.new_layout);
1516		if (!rt) {
1517			rs->ti->error = "Failed to recognize new raid10 layout";
1518			return -EINVAL;
1519		}
1520
1521		if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1522		     rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1523		    test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1524			rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1525			return -EINVAL;
1526		}
1527	}
1528
1529	rs->raid10_copies = raid10_copies;
1530
1531	/* Assume there are no metadata devices until the drives are parsed */
1532	rs->md.persistent = 0;
1533	rs->md.external = 1;
1534
1535	/* Check, if any invalid ctr arguments have been passed in for the raid level */
1536	return rs_check_for_valid_flags(rs);
1537}
1538
1539/* Set raid4/5/6 cache size */
1540static int rs_set_raid456_stripe_cache(struct raid_set *rs)
1541{
1542	int r;
1543	struct r5conf *conf;
1544	struct mddev *mddev = &rs->md;
1545	uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
1546	uint32_t nr_stripes = rs->stripe_cache_entries;
1547
1548	if (!rt_is_raid456(rs->raid_type)) {
1549		rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
1550		return -EINVAL;
1551	}
1552
1553	if (nr_stripes < min_stripes) {
1554		DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
1555		       nr_stripes, min_stripes);
1556		nr_stripes = min_stripes;
1557	}
1558
1559	conf = mddev->private;
1560	if (!conf) {
1561		rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
1562		return -EINVAL;
1563	}
1564
1565	/* Try setting number of stripes in raid456 stripe cache */
1566	if (conf->min_nr_stripes != nr_stripes) {
1567		r = raid5_set_cache_size(mddev, nr_stripes);
1568		if (r) {
1569			rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
1570			return r;
1571		}
1572
1573		DMINFO("%u stripe cache entries", nr_stripes);
1574	}
1575
1576	return 0;
1577}
1578
1579/* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1580static unsigned int mddev_data_stripes(struct raid_set *rs)
1581{
1582	return rs->md.raid_disks - rs->raid_type->parity_devs;
1583}
1584
1585/* Return # of data stripes of @rs (i.e. as of ctr) */
1586static unsigned int rs_data_stripes(struct raid_set *rs)
1587{
1588	return rs->raid_disks - rs->raid_type->parity_devs;
1589}
1590
1591/*
1592 * Retrieve rdev->sectors from any valid raid device of @rs
1593 * to allow userpace to pass in arbitray "- -" device tupples.
1594 */
1595static sector_t __rdev_sectors(struct raid_set *rs)
1596{
1597	int i;
1598
1599	for (i = 0; i < rs->raid_disks; i++) {
1600		struct md_rdev *rdev = &rs->dev[i].rdev;
1601
1602		if (!test_bit(Journal, &rdev->flags) &&
1603		    rdev->bdev && rdev->sectors)
1604			return rdev->sectors;
1605	}
1606
1607	return 0;
1608}
1609
1610/* Check that calculated dev_sectors fits all component devices. */
1611static int _check_data_dev_sectors(struct raid_set *rs)
1612{
1613	sector_t ds = ~0;
1614	struct md_rdev *rdev;
1615
1616	rdev_for_each(rdev, &rs->md)
1617		if (!test_bit(Journal, &rdev->flags) && rdev->bdev) {
1618			ds = min(ds, bdev_nr_sectors(rdev->bdev));
1619			if (ds < rs->md.dev_sectors) {
1620				rs->ti->error = "Component device(s) too small";
1621				return -EINVAL;
1622			}
1623		}
1624
1625	return 0;
1626}
1627
1628/* Calculate the sectors per device and per array used for @rs */
1629static int rs_set_dev_and_array_sectors(struct raid_set *rs, sector_t sectors, bool use_mddev)
1630{
1631	int delta_disks;
1632	unsigned int data_stripes;
1633	sector_t array_sectors = sectors, dev_sectors = sectors;
1634	struct mddev *mddev = &rs->md;
 
 
1635
1636	if (use_mddev) {
1637		delta_disks = mddev->delta_disks;
1638		data_stripes = mddev_data_stripes(rs);
1639	} else {
1640		delta_disks = rs->delta_disks;
1641		data_stripes = rs_data_stripes(rs);
1642	}
1643
1644	/* Special raid1 case w/o delta_disks support (yet) */
1645	if (rt_is_raid1(rs->raid_type))
1646		;
1647	else if (rt_is_raid10(rs->raid_type)) {
1648		if (rs->raid10_copies < 2 ||
1649		    delta_disks < 0) {
1650			rs->ti->error = "Bogus raid10 data copies or delta disks";
1651			return -EINVAL;
1652		}
1653
1654		dev_sectors *= rs->raid10_copies;
1655		if (sector_div(dev_sectors, data_stripes))
1656			goto bad;
1657
1658		array_sectors = (data_stripes + delta_disks) * dev_sectors;
1659		if (sector_div(array_sectors, rs->raid10_copies))
1660			goto bad;
1661
1662	} else if (sector_div(dev_sectors, data_stripes))
1663		goto bad;
1664
1665	else
1666		/* Striped layouts */
1667		array_sectors = (data_stripes + delta_disks) * dev_sectors;
1668
 
 
 
1669	mddev->array_sectors = array_sectors;
1670	mddev->dev_sectors = dev_sectors;
1671	rs_set_rdev_sectors(rs);
1672
1673	return _check_data_dev_sectors(rs);
1674bad:
1675	rs->ti->error = "Target length not divisible by number of data devices";
1676	return -EINVAL;
1677}
1678
1679/* Setup recovery on @rs */
1680static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1681{
1682	/* raid0 does not recover */
1683	if (rs_is_raid0(rs))
1684		rs->md.recovery_cp = MaxSector;
1685	/*
1686	 * A raid6 set has to be recovered either
1687	 * completely or for the grown part to
1688	 * ensure proper parity and Q-Syndrome
1689	 */
1690	else if (rs_is_raid6(rs))
1691		rs->md.recovery_cp = dev_sectors;
1692	/*
1693	 * Other raid set types may skip recovery
1694	 * depending on the 'nosync' flag.
1695	 */
1696	else
1697		rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
1698				     ? MaxSector : dev_sectors;
1699}
1700
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1701static void do_table_event(struct work_struct *ws)
1702{
1703	struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1704
1705	smp_rmb(); /* Make sure we access most actual mddev properties */
1706	if (!rs_is_reshaping(rs)) {
1707		if (rs_is_raid10(rs))
1708			rs_set_rdev_sectors(rs);
1709		rs_set_capacity(rs);
1710	}
1711	dm_table_event(rs->ti->table);
1712}
1713
 
 
 
 
 
 
 
1714/*
1715 * Make sure a valid takover (level switch) is being requested on @rs
1716 *
1717 * Conversions of raid sets from one MD personality to another
1718 * have to conform to restrictions which are enforced here.
1719 */
1720static int rs_check_takeover(struct raid_set *rs)
1721{
1722	struct mddev *mddev = &rs->md;
1723	unsigned int near_copies;
1724
1725	if (rs->md.degraded) {
1726		rs->ti->error = "Can't takeover degraded raid set";
1727		return -EPERM;
1728	}
1729
1730	if (rs_is_reshaping(rs)) {
1731		rs->ti->error = "Can't takeover reshaping raid set";
1732		return -EPERM;
1733	}
1734
1735	switch (mddev->level) {
1736	case 0:
1737		/* raid0 -> raid1/5 with one disk */
1738		if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1739		    mddev->raid_disks == 1)
1740			return 0;
1741
1742		/* raid0 -> raid10 */
1743		if (mddev->new_level == 10 &&
1744		    !(rs->raid_disks % mddev->raid_disks))
1745			return 0;
1746
1747		/* raid0 with multiple disks -> raid4/5/6 */
1748		if (__within_range(mddev->new_level, 4, 6) &&
1749		    mddev->new_layout == ALGORITHM_PARITY_N &&
1750		    mddev->raid_disks > 1)
1751			return 0;
1752
1753		break;
1754
1755	case 10:
1756		/* Can't takeover raid10_offset! */
1757		if (__is_raid10_offset(mddev->layout))
1758			break;
1759
1760		near_copies = __raid10_near_copies(mddev->layout);
1761
1762		/* raid10* -> raid0 */
1763		if (mddev->new_level == 0) {
1764			/* Can takeover raid10_near with raid disks divisable by data copies! */
1765			if (near_copies > 1 &&
1766			    !(mddev->raid_disks % near_copies)) {
1767				mddev->raid_disks /= near_copies;
1768				mddev->delta_disks = mddev->raid_disks;
1769				return 0;
1770			}
1771
1772			/* Can takeover raid10_far */
1773			if (near_copies == 1 &&
1774			    __raid10_far_copies(mddev->layout) > 1)
1775				return 0;
1776
1777			break;
1778		}
1779
1780		/* raid10_{near,far} -> raid1 */
1781		if (mddev->new_level == 1 &&
1782		    max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1783			return 0;
1784
1785		/* raid10_{near,far} with 2 disks -> raid4/5 */
1786		if (__within_range(mddev->new_level, 4, 5) &&
1787		    mddev->raid_disks == 2)
1788			return 0;
1789		break;
1790
1791	case 1:
1792		/* raid1 with 2 disks -> raid4/5 */
1793		if (__within_range(mddev->new_level, 4, 5) &&
1794		    mddev->raid_disks == 2) {
1795			mddev->degraded = 1;
1796			return 0;
1797		}
1798
1799		/* raid1 -> raid0 */
1800		if (mddev->new_level == 0 &&
1801		    mddev->raid_disks == 1)
1802			return 0;
1803
1804		/* raid1 -> raid10 */
1805		if (mddev->new_level == 10)
1806			return 0;
1807		break;
1808
1809	case 4:
1810		/* raid4 -> raid0 */
1811		if (mddev->new_level == 0)
1812			return 0;
1813
1814		/* raid4 -> raid1/5 with 2 disks */
1815		if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1816		    mddev->raid_disks == 2)
1817			return 0;
1818
1819		/* raid4 -> raid5/6 with parity N */
1820		if (__within_range(mddev->new_level, 5, 6) &&
1821		    mddev->layout == ALGORITHM_PARITY_N)
1822			return 0;
1823		break;
1824
1825	case 5:
1826		/* raid5 with parity N -> raid0 */
1827		if (mddev->new_level == 0 &&
1828		    mddev->layout == ALGORITHM_PARITY_N)
1829			return 0;
1830
1831		/* raid5 with parity N -> raid4 */
1832		if (mddev->new_level == 4 &&
1833		    mddev->layout == ALGORITHM_PARITY_N)
1834			return 0;
1835
1836		/* raid5 with 2 disks -> raid1/4/10 */
1837		if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1838		    mddev->raid_disks == 2)
1839			return 0;
1840
1841		/* raid5_* ->  raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
1842		if (mddev->new_level == 6 &&
1843		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1844		      __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1845			return 0;
1846		break;
1847
1848	case 6:
1849		/* raid6 with parity N -> raid0 */
1850		if (mddev->new_level == 0 &&
1851		    mddev->layout == ALGORITHM_PARITY_N)
1852			return 0;
1853
1854		/* raid6 with parity N -> raid4 */
1855		if (mddev->new_level == 4 &&
1856		    mddev->layout == ALGORITHM_PARITY_N)
1857			return 0;
1858
1859		/* raid6_*_n with Q-Syndrome N -> raid5_* */
1860		if (mddev->new_level == 5 &&
1861		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1862		     __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1863			return 0;
1864		break;
1865
1866	default:
1867		break;
1868	}
1869
1870	rs->ti->error = "takeover not possible";
1871	return -EINVAL;
1872}
1873
1874/* True if @rs requested to be taken over */
1875static bool rs_takeover_requested(struct raid_set *rs)
1876{
1877	return rs->md.new_level != rs->md.level;
1878}
1879
1880/* True if layout is set to reshape. */
1881static bool rs_is_layout_change(struct raid_set *rs, bool use_mddev)
1882{
1883	return (use_mddev ? rs->md.delta_disks : rs->delta_disks) ||
1884	       rs->md.new_layout != rs->md.layout ||
1885	       rs->md.new_chunk_sectors != rs->md.chunk_sectors;
1886}
1887
1888/* True if @rs is requested to reshape by ctr */
1889static bool rs_reshape_requested(struct raid_set *rs)
1890{
1891	bool change;
1892	struct mddev *mddev = &rs->md;
1893
1894	if (rs_takeover_requested(rs))
1895		return false;
1896
1897	if (rs_is_raid0(rs))
1898		return false;
1899
1900	change = rs_is_layout_change(rs, false);
 
 
1901
1902	/* Historical case to support raid1 reshape without delta disks */
1903	if (rs_is_raid1(rs)) {
1904		if (rs->delta_disks)
1905			return !!rs->delta_disks;
1906
1907		return !change &&
1908		       mddev->raid_disks != rs->raid_disks;
1909	}
1910
1911	if (rs_is_raid10(rs))
1912		return change &&
1913		       !__is_raid10_far(mddev->new_layout) &&
1914		       rs->delta_disks >= 0;
1915
1916	return change;
1917}
1918
1919/*  Features */
1920#define	FEATURE_FLAG_SUPPORTS_V190	0x1 /* Supports extended superblock */
1921
1922/* State flags for sb->flags */
1923#define	SB_FLAG_RESHAPE_ACTIVE		0x1
1924#define	SB_FLAG_RESHAPE_BACKWARDS	0x2
1925
1926/*
1927 * This structure is never routinely used by userspace, unlike md superblocks.
1928 * Devices with this superblock should only ever be accessed via device-mapper.
1929 */
1930#define DM_RAID_MAGIC 0x64526D44
1931struct dm_raid_superblock {
1932	__le32 magic;		/* "DmRd" */
1933	__le32 compat_features;	/* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1934
1935	__le32 num_devices;	/* Number of devices in this raid set. (Max 64) */
1936	__le32 array_position;	/* The position of this drive in the raid set */
1937
1938	__le64 events;		/* Incremented by md when superblock updated */
1939	__le64 failed_devices;	/* Pre 1.9.0 part of bit field of devices to */
1940				/* indicate failures (see extension below) */
1941
1942	/*
1943	 * This offset tracks the progress of the repair or replacement of
1944	 * an individual drive.
1945	 */
1946	__le64 disk_recovery_offset;
1947
1948	/*
1949	 * This offset tracks the progress of the initial raid set
1950	 * synchronisation/parity calculation.
1951	 */
1952	__le64 array_resync_offset;
1953
1954	/*
1955	 * raid characteristics
1956	 */
1957	__le32 level;
1958	__le32 layout;
1959	__le32 stripe_sectors;
1960
1961	/********************************************************************
1962	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1963	 *
1964	 * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
1965	 */
1966
1967	__le32 flags; /* Flags defining array states for reshaping */
1968
1969	/*
1970	 * This offset tracks the progress of a raid
1971	 * set reshape in order to be able to restart it
1972	 */
1973	__le64 reshape_position;
1974
1975	/*
1976	 * These define the properties of the array in case of an interrupted reshape
1977	 */
1978	__le32 new_level;
1979	__le32 new_layout;
1980	__le32 new_stripe_sectors;
1981	__le32 delta_disks;
1982
1983	__le64 array_sectors; /* Array size in sectors */
1984
1985	/*
1986	 * Sector offsets to data on devices (reshaping).
1987	 * Needed to support out of place reshaping, thus
1988	 * not writing over any stripes whilst converting
1989	 * them from old to new layout
1990	 */
1991	__le64 data_offset;
1992	__le64 new_data_offset;
1993
1994	__le64 sectors; /* Used device size in sectors */
1995
1996	/*
1997	 * Additional Bit field of devices indicating failures to support
1998	 * up to 256 devices with the 1.9.0 on-disk metadata format
1999	 */
2000	__le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
2001
2002	__le32 incompat_features;	/* Used to indicate any incompatible features */
2003
2004	/* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
2005} __packed;
2006
2007/*
2008 * Check for reshape constraints on raid set @rs:
2009 *
2010 * - reshape function non-existent
2011 * - degraded set
2012 * - ongoing recovery
2013 * - ongoing reshape
2014 *
2015 * Returns 0 if none or -EPERM if given constraint
2016 * and error message reference in @errmsg
2017 */
2018static int rs_check_reshape(struct raid_set *rs)
2019{
2020	struct mddev *mddev = &rs->md;
2021
2022	if (!mddev->pers || !mddev->pers->check_reshape)
2023		rs->ti->error = "Reshape not supported";
2024	else if (mddev->degraded)
2025		rs->ti->error = "Can't reshape degraded raid set";
2026	else if (rs_is_recovering(rs))
2027		rs->ti->error = "Convert request on recovering raid set prohibited";
2028	else if (rs_is_reshaping(rs))
2029		rs->ti->error = "raid set already reshaping!";
2030	else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
2031		rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
2032	else
2033		return 0;
2034
2035	return -EPERM;
2036}
2037
2038static int read_disk_sb(struct md_rdev *rdev, int size, bool force_reload)
2039{
2040	BUG_ON(!rdev->sb_page);
2041
2042	if (rdev->sb_loaded && !force_reload)
2043		return 0;
2044
2045	rdev->sb_loaded = 0;
2046
2047	if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, true)) {
2048		DMERR("Failed to read superblock of device at position %d",
2049		      rdev->raid_disk);
2050		md_error(rdev->mddev, rdev);
2051		set_bit(Faulty, &rdev->flags);
2052		return -EIO;
2053	}
2054
2055	rdev->sb_loaded = 1;
2056
2057	return 0;
2058}
2059
2060static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2061{
2062	failed_devices[0] = le64_to_cpu(sb->failed_devices);
2063	memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
2064
2065	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2066		int i = ARRAY_SIZE(sb->extended_failed_devices);
2067
2068		while (i--)
2069			failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
2070	}
2071}
2072
2073static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2074{
2075	int i = ARRAY_SIZE(sb->extended_failed_devices);
2076
2077	sb->failed_devices = cpu_to_le64(failed_devices[0]);
2078	while (i--)
2079		sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
2080}
2081
2082/*
2083 * Synchronize the superblock members with the raid set properties
2084 *
2085 * All superblock data is little endian.
2086 */
2087static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
2088{
2089	bool update_failed_devices = false;
2090	unsigned int i;
2091	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2092	struct dm_raid_superblock *sb;
2093	struct raid_set *rs = container_of(mddev, struct raid_set, md);
2094
2095	/* No metadata device, no superblock */
2096	if (!rdev->meta_bdev)
2097		return;
2098
2099	BUG_ON(!rdev->sb_page);
2100
2101	sb = page_address(rdev->sb_page);
2102
2103	sb_retrieve_failed_devices(sb, failed_devices);
2104
2105	for (i = 0; i < rs->raid_disks; i++)
2106		if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
2107			update_failed_devices = true;
2108			set_bit(i, (void *) failed_devices);
2109		}
2110
2111	if (update_failed_devices)
2112		sb_update_failed_devices(sb, failed_devices);
2113
2114	sb->magic = cpu_to_le32(DM_RAID_MAGIC);
2115	sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2116
2117	sb->num_devices = cpu_to_le32(mddev->raid_disks);
2118	sb->array_position = cpu_to_le32(rdev->raid_disk);
2119
2120	sb->events = cpu_to_le64(mddev->events);
2121
2122	sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
2123	sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
2124
2125	sb->level = cpu_to_le32(mddev->level);
2126	sb->layout = cpu_to_le32(mddev->layout);
2127	sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
2128
2129	/********************************************************************
2130	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
2131	 *
2132	 * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
2133	 */
2134	sb->new_level = cpu_to_le32(mddev->new_level);
2135	sb->new_layout = cpu_to_le32(mddev->new_layout);
2136	sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
2137
2138	sb->delta_disks = cpu_to_le32(mddev->delta_disks);
2139
2140	smp_rmb(); /* Make sure we access most recent reshape position */
2141	sb->reshape_position = cpu_to_le64(mddev->reshape_position);
2142	if (le64_to_cpu(sb->reshape_position) != MaxSector) {
2143		/* Flag ongoing reshape */
2144		sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
2145
2146		if (mddev->delta_disks < 0 || mddev->reshape_backwards)
2147			sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
2148	} else {
2149		/* Clear reshape flags */
2150		sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
2151	}
2152
2153	sb->array_sectors = cpu_to_le64(mddev->array_sectors);
2154	sb->data_offset = cpu_to_le64(rdev->data_offset);
2155	sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
2156	sb->sectors = cpu_to_le64(rdev->sectors);
2157	sb->incompat_features = cpu_to_le32(0);
2158
2159	/* Zero out the rest of the payload after the size of the superblock */
2160	memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
2161}
2162
2163/*
2164 * super_load
2165 *
2166 * This function creates a superblock if one is not found on the device
2167 * and will decide which superblock to use if there's a choice.
2168 *
2169 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
2170 */
2171static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
2172{
2173	int r;
2174	struct dm_raid_superblock *sb;
2175	struct dm_raid_superblock *refsb;
2176	uint64_t events_sb, events_refsb;
2177
2178	r = read_disk_sb(rdev, rdev->sb_size, false);
 
 
 
 
 
 
 
2179	if (r)
2180		return r;
2181
2182	sb = page_address(rdev->sb_page);
2183
2184	/*
2185	 * Two cases that we want to write new superblocks and rebuild:
2186	 * 1) New device (no matching magic number)
2187	 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
2188	 */
2189	if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
2190	    (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
2191		super_sync(rdev->mddev, rdev);
2192
2193		set_bit(FirstUse, &rdev->flags);
2194		sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2195
2196		/* Force writing of superblocks to disk */
2197		set_bit(MD_SB_CHANGE_DEVS, &rdev->mddev->sb_flags);
2198
2199		/* Any superblock is better than none, choose that if given */
2200		return refdev ? 0 : 1;
2201	}
2202
2203	if (!refdev)
2204		return 1;
2205
2206	events_sb = le64_to_cpu(sb->events);
2207
2208	refsb = page_address(refdev->sb_page);
2209	events_refsb = le64_to_cpu(refsb->events);
2210
2211	return (events_sb > events_refsb) ? 1 : 0;
2212}
2213
2214static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
2215{
2216	int role;
 
2217	struct mddev *mddev = &rs->md;
2218	uint64_t events_sb;
2219	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2220	struct dm_raid_superblock *sb;
2221	uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
2222	struct md_rdev *r;
2223	struct dm_raid_superblock *sb2;
2224
2225	sb = page_address(rdev->sb_page);
2226	events_sb = le64_to_cpu(sb->events);
2227
2228	/*
2229	 * Initialise to 1 if this is a new superblock.
2230	 */
2231	mddev->events = events_sb ? : 1;
2232
2233	mddev->reshape_position = MaxSector;
2234
2235	mddev->raid_disks = le32_to_cpu(sb->num_devices);
2236	mddev->level = le32_to_cpu(sb->level);
2237	mddev->layout = le32_to_cpu(sb->layout);
2238	mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
2239
2240	/*
2241	 * Reshaping is supported, e.g. reshape_position is valid
2242	 * in superblock and superblock content is authoritative.
2243	 */
2244	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2245		/* Superblock is authoritative wrt given raid set layout! */
2246		mddev->new_level = le32_to_cpu(sb->new_level);
2247		mddev->new_layout = le32_to_cpu(sb->new_layout);
2248		mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
2249		mddev->delta_disks = le32_to_cpu(sb->delta_disks);
2250		mddev->array_sectors = le64_to_cpu(sb->array_sectors);
2251
2252		/* raid was reshaping and got interrupted */
2253		if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2254			if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2255				DMERR("Reshape requested but raid set is still reshaping");
2256				return -EINVAL;
2257			}
2258
2259			if (mddev->delta_disks < 0 ||
2260			    (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2261				mddev->reshape_backwards = 1;
2262			else
2263				mddev->reshape_backwards = 0;
2264
2265			mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2266			rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
2267		}
2268
2269	} else {
2270		/*
2271		 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2272		 */
2273		struct raid_type *rt_cur = get_raid_type_by_ll(mddev->level, mddev->layout);
2274		struct raid_type *rt_new = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
2275
2276		if (rs_takeover_requested(rs)) {
2277			if (rt_cur && rt_new)
2278				DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",
2279				      rt_cur->name, rt_new->name);
2280			else
2281				DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");
2282			return -EINVAL;
2283		} else if (rs_reshape_requested(rs)) {
2284			DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");
2285			if (mddev->layout != mddev->new_layout) {
2286				if (rt_cur && rt_new)
2287					DMERR("	 current layout %s vs new layout %s",
2288					      rt_cur->name, rt_new->name);
2289				else
2290					DMERR("	 current layout 0x%X vs new layout 0x%X",
2291					      le32_to_cpu(sb->layout), mddev->new_layout);
2292			}
2293			if (mddev->chunk_sectors != mddev->new_chunk_sectors)
2294				DMERR("	 current stripe sectors %u vs new stripe sectors %u",
2295				      mddev->chunk_sectors, mddev->new_chunk_sectors);
2296			if (rs->delta_disks)
2297				DMERR("	 current %u disks vs new %u disks",
2298				      mddev->raid_disks, mddev->raid_disks + rs->delta_disks);
2299			if (rs_is_raid10(rs)) {
2300				DMERR("	 Old layout: %s w/ %u copies",
2301				      raid10_md_layout_to_format(mddev->layout),
2302				      raid10_md_layout_to_copies(mddev->layout));
2303				DMERR("	 New layout: %s w/ %u copies",
2304				      raid10_md_layout_to_format(mddev->new_layout),
2305				      raid10_md_layout_to_copies(mddev->new_layout));
2306			}
2307			return -EINVAL;
2308		}
2309
2310		DMINFO("Discovered old metadata format; upgrading to extended metadata format");
2311	}
2312
2313	if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2314		mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2315
2316	/*
2317	 * During load, we set FirstUse if a new superblock was written.
2318	 * There are two reasons we might not have a superblock:
2319	 * 1) The raid set is brand new - in which case, all of the
2320	 *    devices must have their In_sync bit set.	Also,
2321	 *    recovery_cp must be 0, unless forced.
2322	 * 2) This is a new device being added to an old raid set
2323	 *    and the new device needs to be rebuilt - in which
2324	 *    case the In_sync bit will /not/ be set and
2325	 *    recovery_cp must be MaxSector.
2326	 * 3) This is/are a new device(s) being added to an old
2327	 *    raid set during takeover to a higher raid level
2328	 *    to provide capacity for redundancy or during reshape
2329	 *    to add capacity to grow the raid set.
2330	 */
 
2331	rdev_for_each(r, mddev) {
2332		if (test_bit(Journal, &rdev->flags))
2333			continue;
2334
2335		if (test_bit(FirstUse, &r->flags))
2336			new_devs++;
2337
2338		if (!test_bit(In_sync, &r->flags)) {
2339			DMINFO("Device %d specified for rebuild; clearing superblock",
2340				r->raid_disk);
2341			rebuilds++;
2342
2343			if (test_bit(FirstUse, &r->flags))
2344				rebuild_and_new++;
2345		}
 
 
2346	}
2347
2348	if (new_devs == rs->raid_disks || !rebuilds) {
2349		/* Replace a broken device */
 
 
2350		if (new_devs == rs->raid_disks) {
2351			DMINFO("Superblocks created for new raid set");
2352			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2353		} else if (new_devs != rebuilds &&
2354			   new_devs != rs->delta_disks) {
2355			DMERR("New device injected into existing raid set without "
2356			      "'delta_disks' or 'rebuild' parameter specified");
2357			return -EINVAL;
2358		}
2359	} else if (new_devs && new_devs != rebuilds) {
2360		DMERR("%u 'rebuild' devices cannot be injected into"
2361		      " a raid set with %u other first-time devices",
2362		      rebuilds, new_devs);
2363		return -EINVAL;
2364	} else if (rebuilds) {
2365		if (rebuild_and_new && rebuilds != rebuild_and_new) {
2366			DMERR("new device%s provided without 'rebuild'",
2367			      new_devs > 1 ? "s" : "");
2368			return -EINVAL;
2369		} else if (!test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && rs_is_recovering(rs)) {
2370			DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2371			      (unsigned long long) mddev->recovery_cp);
2372			return -EINVAL;
2373		} else if (rs_is_reshaping(rs)) {
2374			DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2375			      (unsigned long long) mddev->reshape_position);
2376			return -EINVAL;
2377		}
2378	}
2379
2380	/*
2381	 * Now we set the Faulty bit for those devices that are
2382	 * recorded in the superblock as failed.
2383	 */
2384	sb_retrieve_failed_devices(sb, failed_devices);
2385	rdev_for_each(r, mddev) {
2386		if (test_bit(Journal, &rdev->flags) ||
2387		    !r->sb_page)
2388			continue;
2389		sb2 = page_address(r->sb_page);
2390		sb2->failed_devices = 0;
2391		memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2392
2393		/*
2394		 * Check for any device re-ordering.
2395		 */
2396		if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2397			role = le32_to_cpu(sb2->array_position);
2398			if (role < 0)
2399				continue;
2400
2401			if (role != r->raid_disk) {
2402				if (rs_is_raid10(rs) && __is_raid10_near(mddev->layout)) {
2403					if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2404					    rs->raid_disks % rs->raid10_copies) {
2405						rs->ti->error =
2406							"Cannot change raid10 near set to odd # of devices!";
2407						return -EINVAL;
2408					}
2409
2410					sb2->array_position = cpu_to_le32(r->raid_disk);
2411
2412				} else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2413					   !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2414					   !rt_is_raid1(rs->raid_type)) {
2415					rs->ti->error = "Cannot change device positions in raid set";
2416					return -EINVAL;
2417				}
2418
2419				DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2420			}
2421
2422			/*
2423			 * Partial recovery is performed on
2424			 * returning failed devices.
2425			 */
2426			if (test_bit(role, (void *) failed_devices))
2427				set_bit(Faulty, &r->flags);
2428		}
2429	}
2430
2431	return 0;
2432}
2433
2434static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2435{
2436	struct mddev *mddev = &rs->md;
2437	struct dm_raid_superblock *sb;
2438
2439	if (rs_is_raid0(rs) || !rdev->sb_page || rdev->raid_disk < 0)
2440		return 0;
2441
2442	sb = page_address(rdev->sb_page);
2443
2444	/*
2445	 * If mddev->events is not set, we know we have not yet initialized
2446	 * the array.
2447	 */
2448	if (!mddev->events && super_init_validation(rs, rdev))
2449		return -EINVAL;
2450
2451	if (le32_to_cpu(sb->compat_features) &&
2452	    le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2453		rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2454		return -EINVAL;
2455	}
2456
2457	if (sb->incompat_features) {
2458		rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2459		return -EINVAL;
2460	}
2461
2462	/* Enable bitmap creation on @rs unless no metadevs or raid0 or journaled raid4/5/6 set. */
2463	mddev->bitmap_info.offset = (rt_is_raid0(rs->raid_type) || rs->journal_dev.dev) ? 0 : to_sector(4096);
2464	mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2465
2466	if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2467		/*
2468		 * Retrieve rdev size stored in superblock to be prepared for shrink.
2469		 * Check extended superblock members are present otherwise the size
2470		 * will not be set!
2471		 */
2472		if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190)
2473			rdev->sectors = le64_to_cpu(sb->sectors);
2474
2475		rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2476		if (rdev->recovery_offset == MaxSector)
2477			set_bit(In_sync, &rdev->flags);
2478		/*
2479		 * If no reshape in progress -> we're recovering single
2480		 * disk(s) and have to set the device(s) to out-of-sync
2481		 */
2482		else if (!rs_is_reshaping(rs))
2483			clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2484	}
2485
2486	/*
2487	 * If a device comes back, set it as not In_sync and no longer faulty.
2488	 */
2489	if (test_and_clear_bit(Faulty, &rdev->flags)) {
2490		rdev->recovery_offset = 0;
2491		clear_bit(In_sync, &rdev->flags);
2492		rdev->saved_raid_disk = rdev->raid_disk;
2493	}
2494
2495	/* Reshape support -> restore repective data offsets */
2496	rdev->data_offset = le64_to_cpu(sb->data_offset);
2497	rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2498
2499	return 0;
2500}
2501
2502/*
2503 * Analyse superblocks and select the freshest.
2504 */
2505static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2506{
2507	int r;
2508	struct md_rdev *rdev, *freshest;
 
2509	struct mddev *mddev = &rs->md;
2510
2511	freshest = NULL;
2512	rdev_for_each(rdev, mddev) {
2513		if (test_bit(Journal, &rdev->flags))
2514			continue;
2515
2516		if (!rdev->meta_bdev)
2517			continue;
2518
2519		/* Set superblock offset/size for metadata device. */
2520		rdev->sb_start = 0;
2521		rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
2522		if (rdev->sb_size < sizeof(struct dm_raid_superblock) || rdev->sb_size > PAGE_SIZE) {
2523			DMERR("superblock size of a logical block is no longer valid");
2524			return -EINVAL;
2525		}
2526
2527		/*
2528		 * Skipping super_load due to CTR_FLAG_SYNC will cause
2529		 * the array to undergo initialization again as
2530		 * though it were new.	This is the intended effect
2531		 * of the "sync" directive.
2532		 *
2533		 * With reshaping capability added, we must ensure that
2534		 * the "sync" directive is disallowed during the reshape.
 
2535		 */
2536		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2537			continue;
2538
 
 
 
2539		r = super_load(rdev, freshest);
2540
2541		switch (r) {
2542		case 1:
2543			freshest = rdev;
2544			break;
2545		case 0:
2546			break;
2547		default:
2548			/* This is a failure to read the superblock from the metadata device. */
2549			/*
2550			 * We have to keep any raid0 data/metadata device pairs or
2551			 * the MD raid0 personality will fail to start the array.
2552			 */
2553			if (rs_is_raid0(rs))
2554				continue;
2555
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2556			/*
2557			 * We keep the dm_devs to be able to emit the device tuple
2558			 * properly on the table line in raid_status() (rather than
2559			 * mistakenly acting as if '- -' got passed into the constructor).
2560			 *
2561			 * The rdev has to stay on the same_set list to allow for
2562			 * the attempt to restore faulty devices on second resume.
2563			 */
2564			rdev->raid_disk = rdev->saved_raid_disk = -1;
2565			break;
 
 
 
 
 
2566		}
2567	}
2568
2569	if (!freshest)
2570		return 0;
2571
 
 
 
 
 
2572	/*
2573	 * Validation of the freshest device provides the source of
2574	 * validation for the remaining devices.
2575	 */
2576	rs->ti->error = "Unable to assemble array: Invalid superblocks";
2577	if (super_validate(rs, freshest))
2578		return -EINVAL;
2579
2580	if (validate_raid_redundancy(rs)) {
2581		rs->ti->error = "Insufficient redundancy to activate array";
2582		return -EINVAL;
2583	}
2584
2585	rdev_for_each(rdev, mddev)
2586		if (!test_bit(Journal, &rdev->flags) &&
2587		    rdev != freshest &&
2588		    super_validate(rs, rdev))
2589			return -EINVAL;
2590	return 0;
2591}
2592
2593/*
2594 * Adjust data_offset and new_data_offset on all disk members of @rs
2595 * for out of place reshaping if requested by constructor
2596 *
2597 * We need free space at the beginning of each raid disk for forward
2598 * and at the end for backward reshapes which userspace has to provide
2599 * via remapping/reordering of space.
2600 */
2601static int rs_adjust_data_offsets(struct raid_set *rs)
2602{
2603	sector_t data_offset = 0, new_data_offset = 0;
2604	struct md_rdev *rdev;
2605
2606	/* Constructor did not request data offset change */
2607	if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2608		if (!rs_is_reshapable(rs))
2609			goto out;
2610
2611		return 0;
2612	}
2613
2614	/* HM FIXME: get In_Sync raid_dev? */
2615	rdev = &rs->dev[0].rdev;
2616
2617	if (rs->delta_disks < 0) {
2618		/*
2619		 * Removing disks (reshaping backwards):
2620		 *
2621		 * - before reshape: data is at offset 0 and free space
2622		 *		     is at end of each component LV
2623		 *
2624		 * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2625		 */
2626		data_offset = 0;
2627		new_data_offset = rs->data_offset;
2628
2629	} else if (rs->delta_disks > 0) {
2630		/*
2631		 * Adding disks (reshaping forwards):
2632		 *
2633		 * - before reshape: data is at offset rs->data_offset != 0 and
2634		 *		     free space is at begin of each component LV
2635		 *
2636		 * - after reshape: data is at offset 0 on each component LV
2637		 */
2638		data_offset = rs->data_offset;
2639		new_data_offset = 0;
2640
2641	} else {
2642		/*
2643		 * User space passes in 0 for data offset after having removed reshape space
2644		 *
2645		 * - or - (data offset != 0)
2646		 *
2647		 * Changing RAID layout or chunk size -> toggle offsets
2648		 *
2649		 * - before reshape: data is at offset rs->data_offset 0 and
2650		 *		     free space is at end of each component LV
2651		 *		     -or-
2652		 *                   data is at offset rs->data_offset != 0 and
2653		 *		     free space is at begin of each component LV
2654		 *
2655		 * - after reshape: data is at offset 0 if it was at offset != 0
2656		 *                  or at offset != 0 if it was at offset 0
2657		 *                  on each component LV
2658		 *
2659		 */
2660		data_offset = rs->data_offset ? rdev->data_offset : 0;
2661		new_data_offset = data_offset ? 0 : rs->data_offset;
2662		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2663	}
2664
2665	/*
2666	 * Make sure we got a minimum amount of free sectors per device
2667	 */
2668	if (rs->data_offset &&
2669	    bdev_nr_sectors(rdev->bdev) - rs->md.dev_sectors < MIN_FREE_RESHAPE_SPACE) {
2670		rs->ti->error = data_offset ? "No space for forward reshape" :
2671					      "No space for backward reshape";
2672		return -ENOSPC;
2673	}
2674out:
2675	/*
2676	 * Raise recovery_cp in case data_offset != 0 to
2677	 * avoid false recovery positives in the constructor.
2678	 */
2679	if (rs->md.recovery_cp < rs->md.dev_sectors)
2680		rs->md.recovery_cp += rs->dev[0].rdev.data_offset;
2681
2682	/* Adjust data offsets on all rdevs but on any raid4/5/6 journal device */
2683	rdev_for_each(rdev, &rs->md) {
2684		if (!test_bit(Journal, &rdev->flags)) {
2685			rdev->data_offset = data_offset;
2686			rdev->new_data_offset = new_data_offset;
2687		}
2688	}
2689
2690	return 0;
2691}
2692
2693/* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2694static void __reorder_raid_disk_indexes(struct raid_set *rs)
2695{
2696	int i = 0;
2697	struct md_rdev *rdev;
2698
2699	rdev_for_each(rdev, &rs->md) {
2700		if (!test_bit(Journal, &rdev->flags)) {
2701			rdev->raid_disk = i++;
2702			rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2703		}
2704	}
2705}
2706
2707/*
2708 * Setup @rs for takeover by a different raid level
2709 */
2710static int rs_setup_takeover(struct raid_set *rs)
2711{
2712	struct mddev *mddev = &rs->md;
2713	struct md_rdev *rdev;
2714	unsigned int d = mddev->raid_disks = rs->raid_disks;
2715	sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2716
2717	if (rt_is_raid10(rs->raid_type)) {
2718		if (rs_is_raid0(rs)) {
2719			/* Userpace reordered disks -> adjust raid_disk indexes */
2720			__reorder_raid_disk_indexes(rs);
2721
2722			/* raid0 -> raid10_far layout */
2723			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2724								   rs->raid10_copies);
2725		} else if (rs_is_raid1(rs))
2726			/* raid1 -> raid10_near layout */
2727			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2728								   rs->raid_disks);
2729		else
2730			return -EINVAL;
2731
2732	}
2733
2734	clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2735	mddev->recovery_cp = MaxSector;
2736
2737	while (d--) {
2738		rdev = &rs->dev[d].rdev;
2739
2740		if (test_bit(d, (void *) rs->rebuild_disks)) {
2741			clear_bit(In_sync, &rdev->flags);
2742			clear_bit(Faulty, &rdev->flags);
2743			mddev->recovery_cp = rdev->recovery_offset = 0;
2744			/* Bitmap has to be created when we do an "up" takeover */
2745			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2746		}
2747
2748		rdev->new_data_offset = new_data_offset;
2749	}
2750
2751	return 0;
2752}
2753
2754/* Prepare @rs for reshape */
2755static int rs_prepare_reshape(struct raid_set *rs)
2756{
2757	bool reshape;
2758	struct mddev *mddev = &rs->md;
2759
2760	if (rs_is_raid10(rs)) {
2761		if (rs->raid_disks != mddev->raid_disks &&
2762		    __is_raid10_near(mddev->layout) &&
2763		    rs->raid10_copies &&
2764		    rs->raid10_copies != __raid10_near_copies(mddev->layout)) {
2765			/*
2766			 * raid disk have to be multiple of data copies to allow this conversion,
2767			 *
2768			 * This is actually not a reshape it is a
2769			 * rebuild of any additional mirrors per group
2770			 */
2771			if (rs->raid_disks % rs->raid10_copies) {
2772				rs->ti->error = "Can't reshape raid10 mirror groups";
2773				return -EINVAL;
2774			}
2775
2776			/* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2777			__reorder_raid_disk_indexes(rs);
2778			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2779								   rs->raid10_copies);
2780			mddev->new_layout = mddev->layout;
2781			reshape = false;
2782		} else
2783			reshape = true;
2784
2785	} else if (rs_is_raid456(rs))
2786		reshape = true;
2787
2788	else if (rs_is_raid1(rs)) {
2789		if (rs->delta_disks) {
2790			/* Process raid1 via delta_disks */
2791			mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
2792			reshape = true;
2793		} else {
2794			/* Process raid1 without delta_disks */
2795			mddev->raid_disks = rs->raid_disks;
2796			reshape = false;
2797		}
2798	} else {
2799		rs->ti->error = "Called with bogus raid type";
2800		return -EINVAL;
2801	}
2802
2803	if (reshape) {
2804		set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2805		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2806	} else if (mddev->raid_disks < rs->raid_disks)
2807		/* Create new superblocks and bitmaps, if any new disks */
2808		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2809
2810	return 0;
2811}
2812
2813/* Get reshape sectors from data_offsets or raid set */
2814static sector_t _get_reshape_sectors(struct raid_set *rs)
2815{
2816	struct md_rdev *rdev;
2817	sector_t reshape_sectors = 0;
2818
2819	rdev_for_each(rdev, &rs->md)
2820		if (!test_bit(Journal, &rdev->flags)) {
2821			reshape_sectors = (rdev->data_offset > rdev->new_data_offset) ?
2822					rdev->data_offset - rdev->new_data_offset :
2823					rdev->new_data_offset - rdev->data_offset;
2824			break;
2825		}
2826
2827	return max(reshape_sectors, (sector_t) rs->data_offset);
2828}
2829
2830/*
2831 * Reshape:
2832 * - change raid layout
2833 * - change chunk size
2834 * - add disks
2835 * - remove disks
2836 */
2837static int rs_setup_reshape(struct raid_set *rs)
2838{
2839	int r = 0;
2840	unsigned int cur_raid_devs, d;
2841	sector_t reshape_sectors = _get_reshape_sectors(rs);
2842	struct mddev *mddev = &rs->md;
2843	struct md_rdev *rdev;
2844
2845	mddev->delta_disks = rs->delta_disks;
2846	cur_raid_devs = mddev->raid_disks;
2847
2848	/* Ignore impossible layout change whilst adding/removing disks */
2849	if (mddev->delta_disks &&
2850	    mddev->layout != mddev->new_layout) {
2851		DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2852		mddev->new_layout = mddev->layout;
2853	}
2854
2855	/*
2856	 * Adjust array size:
2857	 *
2858	 * - in case of adding disk(s), array size has
2859	 *   to grow after the disk adding reshape,
2860	 *   which'll happen in the event handler;
2861	 *   reshape will happen forward, so space has to
2862	 *   be available at the beginning of each disk
2863	 *
2864	 * - in case of removing disk(s), array size
2865	 *   has to shrink before starting the reshape,
2866	 *   which'll happen here;
2867	 *   reshape will happen backward, so space has to
2868	 *   be available at the end of each disk
2869	 *
2870	 * - data_offset and new_data_offset are
2871	 *   adjusted for aforementioned out of place
2872	 *   reshaping based on userspace passing in
2873	 *   the "data_offset <sectors>" key/value
2874	 *   pair via the constructor
2875	 */
2876
2877	/* Add disk(s) */
2878	if (rs->delta_disks > 0) {
2879		/* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2880		for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2881			rdev = &rs->dev[d].rdev;
2882			clear_bit(In_sync, &rdev->flags);
2883
2884			/*
2885			 * save_raid_disk needs to be -1, or recovery_offset will be set to 0
2886			 * by md, which'll store that erroneously in the superblock on reshape
2887			 */
2888			rdev->saved_raid_disk = -1;
2889			rdev->raid_disk = d;
2890
2891			rdev->sectors = mddev->dev_sectors;
2892			rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
2893		}
2894
2895		mddev->reshape_backwards = 0; /* adding disk(s) -> forward reshape */
2896
2897	/* Remove disk(s) */
2898	} else if (rs->delta_disks < 0) {
2899		r = rs_set_dev_and_array_sectors(rs, rs->ti->len, true);
2900		mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2901
2902	/* Change layout and/or chunk size */
2903	} else {
2904		/*
2905		 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2906		 *
2907		 * keeping number of disks and do layout change ->
2908		 *
2909		 * toggle reshape_backward depending on data_offset:
2910		 *
2911		 * - free space upfront -> reshape forward
2912		 *
2913		 * - free space at the end -> reshape backward
2914		 *
2915		 *
2916		 * This utilizes free reshape space avoiding the need
2917		 * for userspace to move (parts of) LV segments in
2918		 * case of layout/chunksize change  (for disk
2919		 * adding/removing reshape space has to be at
2920		 * the proper address (see above with delta_disks):
2921		 *
2922		 * add disk(s)   -> begin
2923		 * remove disk(s)-> end
2924		 */
2925		mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2926	}
2927
2928	/*
2929	 * Adjust device size for forward reshape
2930	 * because md_finish_reshape() reduces it.
2931	 */
2932	if (!mddev->reshape_backwards)
2933		rdev_for_each(rdev, &rs->md)
2934			if (!test_bit(Journal, &rdev->flags))
2935				rdev->sectors += reshape_sectors;
2936
2937	return r;
2938}
2939
2940/*
2941 * If the md resync thread has updated superblock with max reshape position
2942 * at the end of a reshape but not (yet) reset the layout configuration
2943 * changes -> reset the latter.
2944 */
2945static void rs_reset_inconclusive_reshape(struct raid_set *rs)
2946{
2947	if (!rs_is_reshaping(rs) && rs_is_layout_change(rs, true)) {
2948		rs_set_cur(rs);
2949		rs->md.delta_disks = 0;
2950		rs->md.reshape_backwards = 0;
2951	}
2952}
2953
2954/*
2955 * Enable/disable discard support on RAID set depending on
2956 * RAID level and discard properties of underlying RAID members.
2957 */
2958static void configure_discard_support(struct raid_set *rs)
2959{
2960	int i;
2961	bool raid456;
2962	struct dm_target *ti = rs->ti;
2963
2964	/*
2965	 * XXX: RAID level 4,5,6 require zeroing for safety.
2966	 */
2967	raid456 = rs_is_raid456(rs);
 
2968
2969	for (i = 0; i < rs->raid_disks; i++) {
2970		if (!rs->dev[i].rdev.bdev ||
2971		    !bdev_max_discard_sectors(rs->dev[i].rdev.bdev))
 
 
 
 
 
2972			return;
2973
2974		if (raid456) {
 
 
2975			if (!devices_handle_discard_safely) {
2976				DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2977				DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2978				return;
2979			}
2980		}
2981	}
2982
 
 
 
 
 
 
 
 
2983	ti->num_discard_bios = 1;
2984}
2985
2986/*
2987 * Construct a RAID0/1/10/4/5/6 mapping:
2988 * Args:
2989 *	<raid_type> <#raid_params> <raid_params>{0,}	\
2990 *	<#raid_devs> [<meta_dev1> <dev1>]{1,}
2991 *
2992 * <raid_params> varies by <raid_type>.	 See 'parse_raid_params' for
2993 * details on possible <raid_params>.
2994 *
2995 * Userspace is free to initialize the metadata devices, hence the superblocks to
2996 * enforce recreation based on the passed in table parameters.
2997 *
2998 */
2999static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
3000{
3001	int r;
3002	bool resize = false;
3003	struct raid_type *rt;
3004	unsigned int num_raid_params, num_raid_devs;
3005	sector_t sb_array_sectors, rdev_sectors, reshape_sectors;
3006	struct raid_set *rs = NULL;
3007	const char *arg;
3008	struct rs_layout rs_layout;
3009	struct dm_arg_set as = { argc, argv }, as_nrd;
3010	struct dm_arg _args[] = {
3011		{ 0, as.argc, "Cannot understand number of raid parameters" },
3012		{ 1, 254, "Cannot understand number of raid devices parameters" }
3013	};
3014
 
3015	arg = dm_shift_arg(&as);
3016	if (!arg) {
3017		ti->error = "No arguments";
3018		return -EINVAL;
3019	}
3020
3021	rt = get_raid_type(arg);
3022	if (!rt) {
3023		ti->error = "Unrecognised raid_type";
3024		return -EINVAL;
3025	}
3026
3027	/* Must have <#raid_params> */
3028	if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
3029		return -EINVAL;
3030
3031	/* number of raid device tupples <meta_dev data_dev> */
3032	as_nrd = as;
3033	dm_consume_args(&as_nrd, num_raid_params);
3034	_args[1].max = (as_nrd.argc - 1) / 2;
3035	if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
3036		return -EINVAL;
3037
3038	if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
3039		ti->error = "Invalid number of supplied raid devices";
3040		return -EINVAL;
3041	}
3042
3043	rs = raid_set_alloc(ti, rt, num_raid_devs);
3044	if (IS_ERR(rs))
3045		return PTR_ERR(rs);
3046
3047	r = parse_raid_params(rs, &as, num_raid_params);
3048	if (r)
3049		goto bad;
3050
3051	r = parse_dev_params(rs, &as);
3052	if (r)
3053		goto bad;
3054
3055	rs->md.sync_super = super_sync;
3056
3057	/*
3058	 * Calculate ctr requested array and device sizes to allow
3059	 * for superblock analysis needing device sizes defined.
3060	 *
3061	 * Any existing superblock will overwrite the array and device sizes
3062	 */
3063	r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);
3064	if (r)
3065		goto bad;
3066
3067	/* Memorize just calculated, potentially larger sizes to grow the raid set in preresume */
3068	rs->array_sectors = rs->md.array_sectors;
3069	rs->dev_sectors = rs->md.dev_sectors;
3070
3071	/*
3072	 * Backup any new raid set level, layout, ...
3073	 * requested to be able to compare to superblock
3074	 * members for conversion decisions.
3075	 */
3076	rs_config_backup(rs, &rs_layout);
3077
3078	r = analyse_superblocks(ti, rs);
3079	if (r)
3080		goto bad;
3081
3082	/* All in-core metadata now as of current superblocks after calling analyse_superblocks() */
3083	sb_array_sectors = rs->md.array_sectors;
3084	rdev_sectors = __rdev_sectors(rs);
3085	if (!rdev_sectors) {
3086		ti->error = "Invalid rdev size";
3087		r = -EINVAL;
3088		goto bad;
3089	}
3090
3091
3092	reshape_sectors = _get_reshape_sectors(rs);
3093	if (rs->dev_sectors != rdev_sectors) {
3094		resize = (rs->dev_sectors != rdev_sectors - reshape_sectors);
3095		if (rs->dev_sectors > rdev_sectors - reshape_sectors)
3096			set_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3097	}
3098
3099	INIT_WORK(&rs->md.event_work, do_table_event);
3100	ti->private = rs;
3101	ti->num_flush_bios = 1;
3102	ti->needs_bio_set_dev = true;
3103
3104	/* Restore any requested new layout for conversion decision */
3105	rs_config_restore(rs, &rs_layout);
3106
3107	/*
3108	 * Now that we have any superblock metadata available,
3109	 * check for new, recovering, reshaping, to be taken over,
3110	 * to be reshaped or an existing, unchanged raid set to
3111	 * run in sequence.
3112	 */
3113	if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
3114		/* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
3115		if (rs_is_raid6(rs) &&
3116		    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
3117			ti->error = "'nosync' not allowed for new raid6 set";
3118			r = -EINVAL;
3119			goto bad;
3120		}
3121		rs_setup_recovery(rs, 0);
3122		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3123		rs_set_new(rs);
3124	} else if (rs_is_recovering(rs)) {
3125		/* A recovering raid set may be resized */
3126		goto size_check;
3127	} else if (rs_is_reshaping(rs)) {
3128		/* Have to reject size change request during reshape */
3129		if (resize) {
3130			ti->error = "Can't resize a reshaping raid set";
3131			r = -EPERM;
3132			goto bad;
3133		}
3134		/* skip setup rs */
3135	} else if (rs_takeover_requested(rs)) {
3136		if (rs_is_reshaping(rs)) {
3137			ti->error = "Can't takeover a reshaping raid set";
3138			r = -EPERM;
3139			goto bad;
3140		}
3141
3142		/* We can't takeover a journaled raid4/5/6 */
3143		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3144			ti->error = "Can't takeover a journaled raid4/5/6 set";
3145			r = -EPERM;
3146			goto bad;
3147		}
3148
3149		/*
3150		 * If a takeover is needed, userspace sets any additional
3151		 * devices to rebuild and we can check for a valid request here.
3152		 *
3153		 * If acceptable, set the level to the new requested
3154		 * one, prohibit requesting recovery, allow the raid
3155		 * set to run and store superblocks during resume.
3156		 */
3157		r = rs_check_takeover(rs);
3158		if (r)
3159			goto bad;
3160
3161		r = rs_setup_takeover(rs);
3162		if (r)
3163			goto bad;
3164
3165		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3166		/* Takeover ain't recovery, so disable recovery */
3167		rs_setup_recovery(rs, MaxSector);
3168		rs_set_new(rs);
3169	} else if (rs_reshape_requested(rs)) {
3170		/* Only request grow on raid set size extensions, not on reshapes. */
3171		clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3172
3173		/*
3174		 * No need to check for 'ongoing' takeover here, because takeover
3175		 * is an instant operation as oposed to an ongoing reshape.
3176		 */
3177
3178		/* We can't reshape a journaled raid4/5/6 */
3179		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3180			ti->error = "Can't reshape a journaled raid4/5/6 set";
3181			r = -EPERM;
3182			goto bad;
3183		}
3184
3185		/* Out-of-place space has to be available to allow for a reshape unless raid1! */
3186		if (reshape_sectors || rs_is_raid1(rs)) {
3187			/*
3188			 * We can only prepare for a reshape here, because the
3189			 * raid set needs to run to provide the repective reshape
3190			 * check functions via its MD personality instance.
3191			 *
3192			 * So do the reshape check after md_run() succeeded.
3193			 */
3194			r = rs_prepare_reshape(rs);
3195			if (r)
3196				goto bad;
3197
3198			/* Reshaping ain't recovery, so disable recovery */
3199			rs_setup_recovery(rs, MaxSector);
3200		}
3201		rs_set_cur(rs);
3202	} else {
3203size_check:
3204		/* May not set recovery when a device rebuild is requested */
3205		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
3206			clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3207			set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3208			rs_setup_recovery(rs, MaxSector);
3209		} else if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
3210			/*
3211			 * Set raid set to current size, i.e. size as of
3212			 * superblocks to grow to larger size in preresume.
3213			 */
3214			r = rs_set_dev_and_array_sectors(rs, sb_array_sectors, false);
3215			if (r)
3216				goto bad;
3217
3218			rs_setup_recovery(rs, rs->md.recovery_cp < rs->md.dev_sectors ? rs->md.recovery_cp : rs->md.dev_sectors);
3219		} else {
3220			/* This is no size change or it is shrinking, update size and record in superblocks */
3221			r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);
3222			if (r)
3223				goto bad;
3224
3225			if (sb_array_sectors > rs->array_sectors)
3226				set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3227		}
3228		rs_set_cur(rs);
3229	}
3230
3231	/* If constructor requested it, change data and new_data offsets */
3232	r = rs_adjust_data_offsets(rs);
3233	if (r)
3234		goto bad;
3235
3236	/* Catch any inconclusive reshape superblock content. */
3237	rs_reset_inconclusive_reshape(rs);
3238
3239	/* Start raid set read-only and assumed clean to change in raid_resume() */
3240	rs->md.ro = 1;
3241	rs->md.in_sync = 1;
3242
3243	/* Keep array frozen until resume. */
3244	set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
3245
3246	/* Has to be held on running the array */
3247	mddev_suspend_and_lock_nointr(&rs->md);
3248	r = md_run(&rs->md);
3249	rs->md.in_sync = 0; /* Assume already marked dirty */
 
3250	if (r) {
3251		ti->error = "Failed to run raid array";
3252		mddev_unlock(&rs->md);
3253		goto bad;
3254	}
3255
3256	r = md_start(&rs->md);
3257	if (r) {
3258		ti->error = "Failed to start raid array";
3259		goto bad_unlock;
3260	}
3261
3262	/* If raid4/5/6 journal mode explicitly requested (only possible with journal dev) -> set it */
3263	if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
3264		r = r5c_journal_mode_set(&rs->md, rs->journal_dev.mode);
3265		if (r) {
3266			ti->error = "Failed to set raid4/5/6 journal mode";
3267			goto bad_unlock;
3268		}
3269	}
3270
3271	set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags);
3272
3273	/* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
3274	if (rs_is_raid456(rs)) {
3275		r = rs_set_raid456_stripe_cache(rs);
3276		if (r)
3277			goto bad_unlock;
3278	}
3279
3280	/* Now do an early reshape check */
3281	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3282		r = rs_check_reshape(rs);
3283		if (r)
3284			goto bad_unlock;
3285
3286		/* Restore new, ctr requested layout to perform check */
3287		rs_config_restore(rs, &rs_layout);
3288
3289		if (rs->md.pers->start_reshape) {
3290			r = rs->md.pers->check_reshape(&rs->md);
3291			if (r) {
3292				ti->error = "Reshape check failed";
3293				goto bad_unlock;
3294			}
3295		}
3296	}
3297
3298	/* Disable/enable discard support on raid set. */
3299	configure_discard_support(rs);
3300
3301	mddev_unlock(&rs->md);
3302	return 0;
3303
3304bad_unlock:
 
3305	md_stop(&rs->md);
3306	mddev_unlock(&rs->md);
3307bad:
3308	raid_set_free(rs);
3309
3310	return r;
3311}
3312
3313static void raid_dtr(struct dm_target *ti)
3314{
3315	struct raid_set *rs = ti->private;
3316
3317	mddev_lock_nointr(&rs->md);
3318	md_stop(&rs->md);
3319	mddev_unlock(&rs->md);
3320
3321	if (work_pending(&rs->md.event_work))
3322		flush_work(&rs->md.event_work);
3323	raid_set_free(rs);
3324}
3325
3326static int raid_map(struct dm_target *ti, struct bio *bio)
3327{
3328	struct raid_set *rs = ti->private;
3329	struct mddev *mddev = &rs->md;
3330
3331	/*
3332	 * If we're reshaping to add disk(s)), ti->len and
3333	 * mddev->array_sectors will differ during the process
3334	 * (ti->len > mddev->array_sectors), so we have to requeue
3335	 * bios with addresses > mddev->array_sectors here or
3336	 * there will occur accesses past EOD of the component
3337	 * data images thus erroring the raid set.
3338	 */
3339	if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
3340		return DM_MAPIO_REQUEUE;
3341
3342	md_handle_request(mddev, bio);
3343
3344	return DM_MAPIO_SUBMITTED;
3345}
3346
3347/* Return sync state string for @state */
3348enum sync_state { st_frozen, st_reshape, st_resync, st_check, st_repair, st_recover, st_idle };
3349static const char *sync_str(enum sync_state state)
3350{
3351	/* Has to be in above sync_state order! */
3352	static const char *sync_strs[] = {
3353		"frozen",
3354		"reshape",
3355		"resync",
3356		"check",
3357		"repair",
3358		"recover",
3359		"idle"
3360	};
3361
3362	return __within_range(state, 0, ARRAY_SIZE(sync_strs) - 1) ? sync_strs[state] : "undef";
3363};
3364
3365/* Return enum sync_state for @mddev derived from @recovery flags */
3366static enum sync_state decipher_sync_action(struct mddev *mddev, unsigned long recovery)
3367{
3368	if (test_bit(MD_RECOVERY_FROZEN, &recovery))
3369		return st_frozen;
3370
3371	/* The MD sync thread can be done with io or be interrupted but still be running */
3372	if (!test_bit(MD_RECOVERY_DONE, &recovery) &&
3373	    (test_bit(MD_RECOVERY_RUNNING, &recovery) ||
3374	     (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery)))) {
3375		if (test_bit(MD_RECOVERY_RESHAPE, &recovery))
3376			return st_reshape;
3377
3378		if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
3379			if (!test_bit(MD_RECOVERY_REQUESTED, &recovery))
3380				return st_resync;
3381			if (test_bit(MD_RECOVERY_CHECK, &recovery))
3382				return st_check;
3383			return st_repair;
3384		}
3385
3386		if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3387			return st_recover;
3388
3389		if (mddev->reshape_position != MaxSector)
3390			return st_reshape;
3391	}
3392
3393	return st_idle;
3394}
3395
3396/*
3397 * Return status string for @rdev
3398 *
3399 * Status characters:
3400 *
3401 *  'D' = Dead/Failed raid set component or raid4/5/6 journal device
3402 *  'a' = Alive but not in-sync raid set component _or_ alive raid4/5/6 'write_back' journal device
3403 *  'A' = Alive and in-sync raid set component _or_ alive raid4/5/6 'write_through' journal device
3404 *  '-' = Non-existing device (i.e. uspace passed '- -' into the ctr)
3405 */
3406static const char *__raid_dev_status(struct raid_set *rs, struct md_rdev *rdev)
3407{
3408	if (!rdev->bdev)
3409		return "-";
3410	else if (test_bit(Faulty, &rdev->flags))
3411		return "D";
3412	else if (test_bit(Journal, &rdev->flags))
3413		return (rs->journal_dev.mode == R5C_JOURNAL_MODE_WRITE_THROUGH) ? "A" : "a";
3414	else if (test_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags) ||
3415		 (!test_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags) &&
3416		  !test_bit(In_sync, &rdev->flags)))
3417		return "a";
3418	else
3419		return "A";
3420}
3421
3422/* Helper to return resync/reshape progress for @rs and runtime flags for raid set in sync / resynching */
3423static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery,
3424				enum sync_state state, sector_t resync_max_sectors)
3425{
3426	sector_t r;
3427	struct mddev *mddev = &rs->md;
3428
3429	clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3430	clear_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
 
3431
3432	if (rs_is_raid0(rs)) {
3433		r = resync_max_sectors;
3434		set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3435
3436	} else {
3437		if (state == st_idle && !test_bit(MD_RECOVERY_INTR, &recovery))
3438			r = mddev->recovery_cp;
3439		else
3440			r = mddev->curr_resync_completed;
3441
3442		if (state == st_idle && r >= resync_max_sectors) {
3443			/*
3444			 * Sync complete.
3445			 */
3446			/* In case we have finished recovering, the array is in sync. */
3447			if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3448				set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
 
 
 
3449
3450		} else if (state == st_recover)
3451			/*
3452			 * In case we are recovering, the array is not in sync
3453			 * and health chars should show the recovering legs.
3454			 *
3455			 * Already retrieved recovery offset from curr_resync_completed above.
3456			 */
3457			;
3458
3459		else if (state == st_resync || state == st_reshape)
 
 
 
 
 
 
3460			/*
3461			 * If "resync/reshape" is occurring, the raid set
3462			 * is or may be out of sync hence the health
3463			 * characters shall be 'a'.
3464			 */
3465			set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3466
3467		else if (state == st_check || state == st_repair)
3468			/*
3469			 * If "check" or "repair" is occurring, the raid set has
3470			 * undergone an initial sync and the health characters
3471			 * should not be 'a' anymore.
3472			 */
3473			set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3474
3475		else if (test_bit(MD_RECOVERY_NEEDED, &recovery))
3476			/*
3477			 * We are idle and recovery is needed, prevent 'A' chars race
3478			 * caused by components still set to in-sync by constructor.
3479			 */
3480			set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3481
3482		else {
3483			/*
3484			 * We are idle and the raid set may be doing an initial
3485			 * sync, or it may be rebuilding individual components.
3486			 * If all the devices are In_sync, then it is the raid set
3487			 * that is being initialized.
3488			 */
3489			struct md_rdev *rdev;
3490
3491			set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3492			rdev_for_each(rdev, mddev)
3493				if (!test_bit(Journal, &rdev->flags) &&
3494				    !test_bit(In_sync, &rdev->flags)) {
3495					clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3496					break;
3497				}
3498		}
3499	}
3500
3501	return min(r, resync_max_sectors);
3502}
3503
3504/* Helper to return @dev name or "-" if !@dev */
3505static const char *__get_dev_name(struct dm_dev *dev)
3506{
3507	return dev ? dev->name : "-";
3508}
3509
3510static void raid_status(struct dm_target *ti, status_type_t type,
3511			unsigned int status_flags, char *result, unsigned int maxlen)
3512{
3513	struct raid_set *rs = ti->private;
3514	struct mddev *mddev = &rs->md;
3515	struct r5conf *conf = rs_is_raid456(rs) ? mddev->private : NULL;
3516	int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3517	unsigned long recovery;
3518	unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3519	unsigned int sz = 0;
3520	unsigned int rebuild_writemostly_count = 0;
 
3521	sector_t progress, resync_max_sectors, resync_mismatches;
3522	enum sync_state state;
3523	struct raid_type *rt;
 
3524
3525	switch (type) {
3526	case STATUSTYPE_INFO:
3527		/* *Should* always succeed */
3528		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3529		if (!rt)
3530			return;
3531
3532		DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3533
3534		/* Access most recent mddev properties for status output */
3535		smp_rmb();
3536		/* Get sensible max sectors even if raid set not yet started */
3537		resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3538				      mddev->resync_max_sectors : mddev->dev_sectors;
3539		recovery = rs->md.recovery;
3540		state = decipher_sync_action(mddev, recovery);
3541		progress = rs_get_progress(rs, recovery, state, resync_max_sectors);
3542		resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
3543				    atomic64_read(&mddev->resync_mismatches) : 0;
 
3544
3545		/* HM FIXME: do we want another state char for raid0? It shows 'D'/'A'/'-' now */
3546		for (i = 0; i < rs->raid_disks; i++)
3547			DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3548
3549		/*
3550		 * In-sync/Reshape ratio:
3551		 *  The in-sync ratio shows the progress of:
3552		 *   - Initializing the raid set
3553		 *   - Rebuilding a subset of devices of the raid set
3554		 *  The user can distinguish between the two by referring
3555		 *  to the status characters.
3556		 *
3557		 *  The reshape ratio shows the progress of
3558		 *  changing the raid layout or the number of
3559		 *  disks of a raid set
3560		 */
3561		DMEMIT(" %llu/%llu", (unsigned long long) progress,
3562				     (unsigned long long) resync_max_sectors);
3563
3564		/*
3565		 * v1.5.0+:
3566		 *
3567		 * Sync action:
3568		 *   See Documentation/admin-guide/device-mapper/dm-raid.rst for
3569		 *   information on each of these states.
3570		 */
3571		DMEMIT(" %s", sync_str(state));
3572
3573		/*
3574		 * v1.5.0+:
3575		 *
3576		 * resync_mismatches/mismatch_cnt
3577		 *   This field shows the number of discrepancies found when
3578		 *   performing a "check" of the raid set.
3579		 */
3580		DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3581
3582		/*
3583		 * v1.9.0+:
3584		 *
3585		 * data_offset (needed for out of space reshaping)
3586		 *   This field shows the data offset into the data
3587		 *   image LV where the first stripes data starts.
3588		 *
3589		 * We keep data_offset equal on all raid disks of the set,
3590		 * so retrieving it from the first raid disk is sufficient.
3591		 */
3592		DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
3593
3594		/*
3595		 * v1.10.0+:
3596		 */
3597		DMEMIT(" %s", test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags) ?
3598			      __raid_dev_status(rs, &rs->journal_dev.rdev) : "-");
3599		break;
3600
3601	case STATUSTYPE_TABLE:
3602		/* Report the table line string you would use to construct this raid set */
3603
3604		/*
3605		 * Count any rebuild or writemostly argument pairs and subtract the
3606		 * hweight count being added below of any rebuild and writemostly ctr flags.
3607		 */
3608		for (i = 0; i < rs->raid_disks; i++) {
3609			rebuild_writemostly_count += (test_bit(i, (void *) rs->rebuild_disks) ? 2 : 0) +
3610						     (test_bit(WriteMostly, &rs->dev[i].rdev.flags) ? 2 : 0);
3611		}
3612		rebuild_writemostly_count -= (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) ? 2 : 0) +
3613					     (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags) ? 2 : 0);
3614		/* Calculate raid parameter count based on ^ rebuild/writemostly argument counts and ctr flags set. */
3615		raid_param_cnt += rebuild_writemostly_count +
3616				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3617				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
3618		/* Emit table line */
3619		/* This has to be in the documented order for userspace! */
3620		DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3621		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3622			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
 
 
 
 
3623		if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3624			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3625		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags))
3626			for (i = 0; i < rs->raid_disks; i++)
3627				if (test_bit(i, (void *) rs->rebuild_disks))
3628					DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD), i);
 
 
 
 
3629		if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3630			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3631					  mddev->bitmap_info.daemon_sleep);
3632		if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3633			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3634					 mddev->sync_speed_min);
3635		if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3636			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3637					 mddev->sync_speed_max);
3638		if (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags))
 
 
 
 
 
3639			for (i = 0; i < rs->raid_disks; i++)
3640				if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3641					DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3642					       rs->dev[i].rdev.raid_disk);
3643		if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3644			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3645					  mddev->bitmap_info.max_write_behind);
3646		if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3647			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3648					 max_nr_stripes);
3649		if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3650			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3651					   (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3652		if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3653			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3654					 raid10_md_layout_to_copies(mddev->layout));
3655		if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3656			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3657					 raid10_md_layout_to_format(mddev->layout));
3658		if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3659			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3660					 max(rs->delta_disks, mddev->delta_disks));
3661		if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3662			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3663					   (unsigned long long) rs->data_offset);
3664		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags))
3665			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV),
3666					__get_dev_name(rs->journal_dev.dev));
3667		if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags))
3668			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE),
3669					 md_journal_mode_to_dm_raid(rs->journal_dev.mode));
3670		DMEMIT(" %d", rs->raid_disks);
3671		for (i = 0; i < rs->raid_disks; i++)
3672			DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
3673					 __get_dev_name(rs->dev[i].data_dev));
3674		break;
3675
3676	case STATUSTYPE_IMA:
3677		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3678		if (!rt)
3679			return;
3680
3681		DMEMIT_TARGET_NAME_VERSION(ti->type);
3682		DMEMIT(",raid_type=%s,raid_disks=%d", rt->name, mddev->raid_disks);
3683
3684		/* Access most recent mddev properties for status output */
3685		smp_rmb();
3686		recovery = rs->md.recovery;
3687		state = decipher_sync_action(mddev, recovery);
3688		DMEMIT(",raid_state=%s", sync_str(state));
3689
3690		for (i = 0; i < rs->raid_disks; i++) {
3691			DMEMIT(",raid_device_%d_status=", i);
3692			DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3693		}
3694
3695		if (rt_is_raid456(rt)) {
3696			DMEMIT(",journal_dev_mode=");
3697			switch (rs->journal_dev.mode) {
3698			case R5C_JOURNAL_MODE_WRITE_THROUGH:
3699				DMEMIT("%s",
3700				       _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_THROUGH].param);
3701				break;
3702			case R5C_JOURNAL_MODE_WRITE_BACK:
3703				DMEMIT("%s",
3704				       _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_BACK].param);
3705				break;
3706			default:
3707				DMEMIT("invalid");
3708				break;
3709			}
3710		}
3711		DMEMIT(";");
3712		break;
3713	}
3714}
3715
3716static int raid_message(struct dm_target *ti, unsigned int argc, char **argv,
3717			char *result, unsigned int maxlen)
3718{
3719	struct raid_set *rs = ti->private;
3720	struct mddev *mddev = &rs->md;
3721
3722	if (!mddev->pers || !mddev->pers->sync_request)
3723		return -EINVAL;
3724
3725	if (!strcasecmp(argv[0], "frozen"))
3726		set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3727	else
3728		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3729
3730	if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
3731		if (mddev->sync_thread) {
3732			set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3733			md_reap_sync_thread(mddev);
3734		}
3735	} else if (decipher_sync_action(mddev, mddev->recovery) != st_idle)
 
3736		return -EBUSY;
3737	else if (!strcasecmp(argv[0], "resync"))
3738		; /* MD_RECOVERY_NEEDED set below */
3739	else if (!strcasecmp(argv[0], "recover"))
3740		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3741	else {
3742		if (!strcasecmp(argv[0], "check")) {
3743			set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3744			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3745			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3746		} else if (!strcasecmp(argv[0], "repair")) {
3747			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3748			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3749		} else
3750			return -EINVAL;
 
 
3751	}
3752	if (mddev->ro == 2) {
3753		/* A write to sync_action is enough to justify
3754		 * canceling read-auto mode
3755		 */
3756		mddev->ro = 0;
3757		if (!mddev->suspended)
3758			md_wakeup_thread(mddev->sync_thread);
3759	}
3760	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3761	if (!mddev->suspended)
3762		md_wakeup_thread(mddev->thread);
3763
3764	return 0;
3765}
3766
3767static int raid_iterate_devices(struct dm_target *ti,
3768				iterate_devices_callout_fn fn, void *data)
3769{
3770	struct raid_set *rs = ti->private;
3771	unsigned int i;
3772	int r = 0;
3773
3774	for (i = 0; !r && i < rs->raid_disks; i++) {
3775		if (rs->dev[i].data_dev) {
3776			r = fn(ti, rs->dev[i].data_dev,
3777			       0, /* No offset on data devs */
3778			       rs->md.dev_sectors, data);
3779		}
3780	}
3781
3782	return r;
3783}
3784
3785static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3786{
3787	struct raid_set *rs = ti->private;
3788	unsigned int chunk_size_bytes = to_bytes(rs->md.chunk_sectors);
3789
3790	blk_limits_io_min(limits, chunk_size_bytes);
3791	blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs));
 
 
 
 
 
 
 
3792}
3793
3794static void raid_postsuspend(struct dm_target *ti)
3795{
3796	struct raid_set *rs = ti->private;
3797
3798	if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
3799		/* Writes have to be stopped before suspending to avoid deadlocks. */
3800		if (!test_bit(MD_RECOVERY_FROZEN, &rs->md.recovery))
3801			md_stop_writes(&rs->md);
3802
3803		mddev_suspend(&rs->md, false);
3804	}
3805}
3806
3807static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3808{
3809	int i;
3810	uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];
3811	unsigned long flags;
3812	bool cleared = false;
3813	struct dm_raid_superblock *sb;
3814	struct mddev *mddev = &rs->md;
3815	struct md_rdev *r;
3816
3817	/* RAID personalities have to provide hot add/remove methods or we need to bail out. */
3818	if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)
3819		return;
3820
3821	memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));
3822
3823	for (i = 0; i < rs->raid_disks; i++) {
3824		r = &rs->dev[i].rdev;
3825		/* HM FIXME: enhance journal device recovery processing */
3826		if (test_bit(Journal, &r->flags))
3827			continue;
3828
3829		if (test_bit(Faulty, &r->flags) &&
3830		    r->meta_bdev && !read_disk_sb(r, r->sb_size, true)) {
3831			DMINFO("Faulty %s device #%d has readable super block."
3832			       "  Attempting to revive it.",
3833			       rs->raid_type->name, i);
3834
3835			/*
3836			 * Faulty bit may be set, but sometimes the array can
3837			 * be suspended before the personalities can respond
3838			 * by removing the device from the array (i.e. calling
3839			 * 'hot_remove_disk').	If they haven't yet removed
3840			 * the failed device, its 'raid_disk' number will be
3841			 * '>= 0' - meaning we must call this function
3842			 * ourselves.
3843			 */
3844			flags = r->flags;
3845			clear_bit(In_sync, &r->flags); /* Mandatory for hot remove. */
3846			if (r->raid_disk >= 0) {
3847				if (mddev->pers->hot_remove_disk(mddev, r)) {
3848					/* Failed to revive this device, try next */
3849					r->flags = flags;
3850					continue;
3851				}
3852			} else
3853				r->raid_disk = r->saved_raid_disk = i;
3854
 
 
 
3855			clear_bit(Faulty, &r->flags);
3856			clear_bit(WriteErrorSeen, &r->flags);
3857
3858			if (mddev->pers->hot_add_disk(mddev, r)) {
3859				/* Failed to revive this device, try next */
3860				r->raid_disk = r->saved_raid_disk = -1;
3861				r->flags = flags;
3862			} else {
3863				clear_bit(In_sync, &r->flags);
3864				r->recovery_offset = 0;
3865				set_bit(i, (void *) cleared_failed_devices);
3866				cleared = true;
3867			}
3868		}
3869	}
3870
3871	/* If any failed devices could be cleared, update all sbs failed_devices bits */
3872	if (cleared) {
3873		uint64_t failed_devices[DISKS_ARRAY_ELEMS];
3874
3875		rdev_for_each(r, &rs->md) {
3876			if (test_bit(Journal, &r->flags))
3877				continue;
3878
3879			sb = page_address(r->sb_page);
3880			sb_retrieve_failed_devices(sb, failed_devices);
3881
3882			for (i = 0; i < DISKS_ARRAY_ELEMS; i++)
3883				failed_devices[i] &= ~cleared_failed_devices[i];
3884
3885			sb_update_failed_devices(sb, failed_devices);
3886		}
3887	}
3888}
3889
3890static int __load_dirty_region_bitmap(struct raid_set *rs)
3891{
3892	int r = 0;
3893
3894	/* Try loading the bitmap unless "raid0", which does not have one */
3895	if (!rs_is_raid0(rs) &&
3896	    !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
3897		r = md_bitmap_load(&rs->md);
3898		if (r)
3899			DMERR("Failed to load bitmap");
3900	}
3901
3902	return r;
3903}
3904
3905/* Enforce updating all superblocks */
3906static void rs_update_sbs(struct raid_set *rs)
3907{
3908	struct mddev *mddev = &rs->md;
3909	int ro = mddev->ro;
3910
3911	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
3912	mddev->ro = 0;
3913	md_update_sb(mddev, 1);
3914	mddev->ro = ro;
3915}
3916
3917/*
3918 * Reshape changes raid algorithm of @rs to new one within personality
3919 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3920 * disks from a raid set thus growing/shrinking it or resizes the set
3921 *
3922 * Call mddev_lock_nointr() before!
3923 */
3924static int rs_start_reshape(struct raid_set *rs)
3925{
3926	int r;
3927	struct mddev *mddev = &rs->md;
3928	struct md_personality *pers = mddev->pers;
3929
3930	/* Don't allow the sync thread to work until the table gets reloaded. */
3931	set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
3932
3933	r = rs_setup_reshape(rs);
3934	if (r)
3935		return r;
3936
 
 
 
 
3937	/*
3938	 * Check any reshape constraints enforced by the personalility
3939	 *
3940	 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3941	 */
3942	r = pers->check_reshape(mddev);
3943	if (r) {
3944		rs->ti->error = "pers->check_reshape() failed";
3945		return r;
3946	}
3947
3948	/*
3949	 * Personality may not provide start reshape method in which
3950	 * case check_reshape above has already covered everything
3951	 */
3952	if (pers->start_reshape) {
3953		r = pers->start_reshape(mddev);
3954		if (r) {
3955			rs->ti->error = "pers->start_reshape() failed";
3956			return r;
3957		}
3958	}
3959
 
 
 
 
3960	/*
3961	 * Now reshape got set up, update superblocks to
3962	 * reflect the fact so that a table reload will
3963	 * access proper superblock content in the ctr.
3964	 */
3965	rs_update_sbs(rs);
3966
3967	return 0;
3968}
3969
3970static int raid_preresume(struct dm_target *ti)
3971{
3972	int r;
3973	struct raid_set *rs = ti->private;
3974	struct mddev *mddev = &rs->md;
3975
3976	/* This is a resume after a suspend of the set -> it's already started. */
3977	if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
3978		return 0;
3979
3980	/*
3981	 * The superblocks need to be updated on disk if the
3982	 * array is new or new devices got added (thus zeroed
3983	 * out by userspace) or __load_dirty_region_bitmap
3984	 * will overwrite them in core with old data or fail.
3985	 */
3986	if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
3987		rs_update_sbs(rs);
3988
3989	/* Load the bitmap from disk unless raid0 */
3990	r = __load_dirty_region_bitmap(rs);
3991	if (r)
3992		return r;
3993
3994	/* We are extending the raid set size, adjust mddev/md_rdev sizes and set capacity. */
3995	if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
3996		mddev->array_sectors = rs->array_sectors;
3997		mddev->dev_sectors = rs->dev_sectors;
3998		rs_set_rdev_sectors(rs);
3999		rs_set_capacity(rs);
4000	}
4001
4002	/* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) or grown device size */
4003	if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
4004	    (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags) ||
4005	     (rs->requested_bitmap_chunk_sectors &&
4006	       mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)))) {
4007		int chunksize = to_bytes(rs->requested_bitmap_chunk_sectors) ?: mddev->bitmap_info.chunksize;
4008
4009		r = md_bitmap_resize(mddev->bitmap, mddev->dev_sectors, chunksize, 0);
4010		if (r)
4011			DMERR("Failed to resize bitmap");
4012	}
4013
4014	/* Check for any resize/reshape on @rs and adjust/initiate */
4015	/* Be prepared for mddev_resume() in raid_resume() */
4016	set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4017	if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
4018		set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
4019		mddev->resync_min = mddev->recovery_cp;
4020		if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags))
4021			mddev->resync_max_sectors = mddev->dev_sectors;
4022	}
4023
 
 
4024	/* Check for any reshape request unless new raid set */
4025	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
4026		/* Initiate a reshape. */
4027		rs_set_rdev_sectors(rs);
4028		mddev_lock_nointr(mddev);
4029		r = rs_start_reshape(rs);
4030		mddev_unlock(mddev);
4031		if (r)
4032			DMWARN("Failed to check/start reshape, continuing without change");
4033		r = 0;
4034	}
4035
4036	return r;
4037}
4038
 
 
4039static void raid_resume(struct dm_target *ti)
4040{
4041	struct raid_set *rs = ti->private;
4042	struct mddev *mddev = &rs->md;
4043
4044	if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
4045		/*
4046		 * A secondary resume while the device is active.
4047		 * Take this opportunity to check whether any failed
4048		 * devices are reachable again.
4049		 */
4050		attempt_restore_of_faulty_devices(rs);
4051	}
4052
4053	if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
4054		/* Only reduce raid set size before running a disk removing reshape. */
4055		if (mddev->delta_disks < 0)
4056			rs_set_capacity(rs);
4057
4058		mddev_lock_nointr(mddev);
 
 
 
 
 
 
 
4059		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4060		mddev->ro = 0;
4061		mddev->in_sync = 0;
4062		mddev_unlock_and_resume(mddev);
4063	}
4064}
4065
4066static struct target_type raid_target = {
4067	.name = "raid",
4068	.version = {1, 15, 1},
4069	.module = THIS_MODULE,
4070	.ctr = raid_ctr,
4071	.dtr = raid_dtr,
4072	.map = raid_map,
4073	.status = raid_status,
4074	.message = raid_message,
4075	.iterate_devices = raid_iterate_devices,
4076	.io_hints = raid_io_hints,
 
4077	.postsuspend = raid_postsuspend,
4078	.preresume = raid_preresume,
4079	.resume = raid_resume,
4080};
4081module_dm(raid);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4082
4083module_param(devices_handle_discard_safely, bool, 0644);
4084MODULE_PARM_DESC(devices_handle_discard_safely,
4085		 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
4086
4087MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
4088MODULE_ALIAS("dm-raid0");
4089MODULE_ALIAS("dm-raid1");
4090MODULE_ALIAS("dm-raid10");
4091MODULE_ALIAS("dm-raid4");
4092MODULE_ALIAS("dm-raid5");
4093MODULE_ALIAS("dm-raid6");
4094MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
4095MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
4096MODULE_LICENSE("GPL");
v4.10.11
 
   1/*
   2 * Copyright (C) 2010-2011 Neil Brown
   3 * Copyright (C) 2010-2016 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 "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
  27static bool devices_handle_discard_safely = false;
 
 
 
 
 
  28
  29/*
  30 * The following flags are used by dm-raid.c to set up the array state.
  31 * They must be cleared before md_run is called.
  32 */
  33#define FirstUse 10		/* rdev flag */
  34
  35struct raid_dev {
  36	/*
  37	 * Two DM devices, one to hold metadata and one to hold the
  38	 * actual data/parity.	The reason for this is to not confuse
  39	 * ti->len and give more flexibility in altering size and
  40	 * characteristics.
  41	 *
  42	 * While it is possible for this device to be associated
  43	 * with a different physical device than the data_dev, it
  44	 * is intended for it to be the same.
  45	 *    |--------- Physical Device ---------|
  46	 *    |- meta_dev -|------ data_dev ------|
  47	 */
  48	struct dm_dev *meta_dev;
  49	struct dm_dev *data_dev;
  50	struct md_rdev rdev;
  51};
  52
  53/*
  54 * Bits for establishing rs->ctr_flags
  55 *
  56 * 1 = no flag value
  57 * 2 = flag with value
  58 */
  59#define __CTR_FLAG_SYNC			0  /* 1 */ /* Not with raid0! */
  60#define __CTR_FLAG_NOSYNC		1  /* 1 */ /* Not with raid0! */
  61#define __CTR_FLAG_REBUILD		2  /* 2 */ /* Not with raid0! */
  62#define __CTR_FLAG_DAEMON_SLEEP		3  /* 2 */ /* Not with raid0! */
  63#define __CTR_FLAG_MIN_RECOVERY_RATE	4  /* 2 */ /* Not with raid0! */
  64#define __CTR_FLAG_MAX_RECOVERY_RATE	5  /* 2 */ /* Not with raid0! */
  65#define __CTR_FLAG_MAX_WRITE_BEHIND	6  /* 2 */ /* Only with raid1! */
  66#define __CTR_FLAG_WRITE_MOSTLY		7  /* 2 */ /* Only with raid1! */
  67#define __CTR_FLAG_STRIPE_CACHE		8  /* 2 */ /* Only with raid4/5/6! */
  68#define __CTR_FLAG_REGION_SIZE		9  /* 2 */ /* Not with raid0! */
  69#define __CTR_FLAG_RAID10_COPIES	10 /* 2 */ /* Only with raid10 */
  70#define __CTR_FLAG_RAID10_FORMAT	11 /* 2 */ /* Only with raid10 */
  71/* New for v1.9.0 */
  72#define __CTR_FLAG_DELTA_DISKS		12 /* 2 */ /* Only with reshapable raid1/4/5/6/10! */
  73#define __CTR_FLAG_DATA_OFFSET		13 /* 2 */ /* Only with reshapable raid4/5/6/10! */
  74#define __CTR_FLAG_RAID10_USE_NEAR_SETS 14 /* 2 */ /* Only with raid10! */
  75
 
 
 
 
 
 
  76/*
  77 * Flags for rs->ctr_flags field.
  78 */
  79#define CTR_FLAG_SYNC			(1 << __CTR_FLAG_SYNC)
  80#define CTR_FLAG_NOSYNC			(1 << __CTR_FLAG_NOSYNC)
  81#define CTR_FLAG_REBUILD		(1 << __CTR_FLAG_REBUILD)
  82#define CTR_FLAG_DAEMON_SLEEP		(1 << __CTR_FLAG_DAEMON_SLEEP)
  83#define CTR_FLAG_MIN_RECOVERY_RATE	(1 << __CTR_FLAG_MIN_RECOVERY_RATE)
  84#define CTR_FLAG_MAX_RECOVERY_RATE	(1 << __CTR_FLAG_MAX_RECOVERY_RATE)
  85#define CTR_FLAG_MAX_WRITE_BEHIND	(1 << __CTR_FLAG_MAX_WRITE_BEHIND)
  86#define CTR_FLAG_WRITE_MOSTLY		(1 << __CTR_FLAG_WRITE_MOSTLY)
  87#define CTR_FLAG_STRIPE_CACHE		(1 << __CTR_FLAG_STRIPE_CACHE)
  88#define CTR_FLAG_REGION_SIZE		(1 << __CTR_FLAG_REGION_SIZE)
  89#define CTR_FLAG_RAID10_COPIES		(1 << __CTR_FLAG_RAID10_COPIES)
  90#define CTR_FLAG_RAID10_FORMAT		(1 << __CTR_FLAG_RAID10_FORMAT)
  91#define CTR_FLAG_DELTA_DISKS		(1 << __CTR_FLAG_DELTA_DISKS)
  92#define CTR_FLAG_DATA_OFFSET		(1 << __CTR_FLAG_DATA_OFFSET)
  93#define CTR_FLAG_RAID10_USE_NEAR_SETS	(1 << __CTR_FLAG_RAID10_USE_NEAR_SETS)
 
 
  94
  95/*
  96 * Definitions of various constructor flags to
  97 * be used in checks of valid / invalid flags
  98 * per raid level.
  99 */
 100/* Define all any sync flags */
 101#define	CTR_FLAGS_ANY_SYNC		(CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)
 102
 103/* Define flags for options without argument (e.g. 'nosync') */
 104#define	CTR_FLAG_OPTIONS_NO_ARGS	(CTR_FLAGS_ANY_SYNC | \
 105					 CTR_FLAG_RAID10_USE_NEAR_SETS)
 106
 107/* Define flags for options with one argument (e.g. 'delta_disks +2') */
 108#define CTR_FLAG_OPTIONS_ONE_ARG (CTR_FLAG_REBUILD | \
 109				  CTR_FLAG_WRITE_MOSTLY | \
 110				  CTR_FLAG_DAEMON_SLEEP | \
 111				  CTR_FLAG_MIN_RECOVERY_RATE | \
 112				  CTR_FLAG_MAX_RECOVERY_RATE | \
 113				  CTR_FLAG_MAX_WRITE_BEHIND | \
 114				  CTR_FLAG_STRIPE_CACHE | \
 115				  CTR_FLAG_REGION_SIZE | \
 116				  CTR_FLAG_RAID10_COPIES | \
 117				  CTR_FLAG_RAID10_FORMAT | \
 118				  CTR_FLAG_DELTA_DISKS | \
 119				  CTR_FLAG_DATA_OFFSET)
 
 
 120
 121/* Valid options definitions per raid level... */
 122
 123/* "raid0" does only accept data offset */
 124#define RAID0_VALID_FLAGS	(CTR_FLAG_DATA_OFFSET)
 125
 126/* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */
 127#define RAID1_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 128				 CTR_FLAG_REBUILD | \
 129				 CTR_FLAG_WRITE_MOSTLY | \
 130				 CTR_FLAG_DAEMON_SLEEP | \
 131				 CTR_FLAG_MIN_RECOVERY_RATE | \
 132				 CTR_FLAG_MAX_RECOVERY_RATE | \
 133				 CTR_FLAG_MAX_WRITE_BEHIND | \
 134				 CTR_FLAG_REGION_SIZE | \
 135				 CTR_FLAG_DELTA_DISKS | \
 136				 CTR_FLAG_DATA_OFFSET)
 137
 138/* "raid10" does not accept any raid1 or stripe cache options */
 139#define RAID10_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 140				 CTR_FLAG_REBUILD | \
 141				 CTR_FLAG_DAEMON_SLEEP | \
 142				 CTR_FLAG_MIN_RECOVERY_RATE | \
 143				 CTR_FLAG_MAX_RECOVERY_RATE | \
 144				 CTR_FLAG_REGION_SIZE | \
 145				 CTR_FLAG_RAID10_COPIES | \
 146				 CTR_FLAG_RAID10_FORMAT | \
 147				 CTR_FLAG_DELTA_DISKS | \
 148				 CTR_FLAG_DATA_OFFSET | \
 149				 CTR_FLAG_RAID10_USE_NEAR_SETS)
 150
 151/*
 152 * "raid4/5/6" do not accept any raid1 or raid10 specific options
 153 *
 154 * "raid6" does not accept "nosync", because it is not guaranteed
 155 * that both parity and q-syndrome are being written properly with
 156 * any writes
 157 */
 158#define RAID45_VALID_FLAGS	(CTR_FLAGS_ANY_SYNC | \
 159				 CTR_FLAG_REBUILD | \
 160				 CTR_FLAG_DAEMON_SLEEP | \
 161				 CTR_FLAG_MIN_RECOVERY_RATE | \
 162				 CTR_FLAG_MAX_RECOVERY_RATE | \
 163				 CTR_FLAG_STRIPE_CACHE | \
 164				 CTR_FLAG_REGION_SIZE | \
 165				 CTR_FLAG_DELTA_DISKS | \
 166				 CTR_FLAG_DATA_OFFSET)
 
 
 167
 168#define RAID6_VALID_FLAGS	(CTR_FLAG_SYNC | \
 169				 CTR_FLAG_REBUILD | \
 170				 CTR_FLAG_DAEMON_SLEEP | \
 171				 CTR_FLAG_MIN_RECOVERY_RATE | \
 172				 CTR_FLAG_MAX_RECOVERY_RATE | \
 173				 CTR_FLAG_STRIPE_CACHE | \
 174				 CTR_FLAG_REGION_SIZE | \
 175				 CTR_FLAG_DELTA_DISKS | \
 176				 CTR_FLAG_DATA_OFFSET)
 
 
 177/* ...valid options definitions per raid level */
 178
 179/*
 180 * Flags for rs->runtime_flags field
 181 * (RT_FLAG prefix meaning "runtime flag")
 182 *
 183 * These are all internal and used to define runtime state,
 184 * e.g. to prevent another resume from preresume processing
 185 * the raid set all over again.
 186 */
 187#define RT_FLAG_RS_PRERESUMED		0
 188#define RT_FLAG_RS_RESUMED		1
 189#define RT_FLAG_RS_BITMAP_LOADED	2
 190#define RT_FLAG_UPDATE_SBS		3
 191#define RT_FLAG_RESHAPE_RS		4
 
 
 
 
 192
 193/* Array elements of 64 bit needed for rebuild/failed disk bits */
 194#define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
 195
 196/*
 197 * raid set level, layout and chunk sectors backup/restore
 198 */
 199struct rs_layout {
 200	int new_level;
 201	int new_layout;
 202	int new_chunk_sectors;
 203};
 204
 205struct raid_set {
 206	struct dm_target *ti;
 207
 208	uint32_t bitmap_loaded;
 209	uint32_t stripe_cache_entries;
 210	unsigned long ctr_flags;
 211	unsigned long runtime_flags;
 212
 213	uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
 214
 215	int raid_disks;
 216	int delta_disks;
 217	int data_offset;
 218	int raid10_copies;
 219	int requested_bitmap_chunk_sectors;
 220
 221	struct mddev md;
 222	struct raid_type *raid_type;
 223	struct dm_target_callbacks callbacks;
 224
 225	struct raid_dev dev[0];
 
 
 
 
 
 
 
 
 
 
 226};
 227
 228static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)
 229{
 230	struct mddev *mddev = &rs->md;
 231
 232	l->new_level = mddev->new_level;
 233	l->new_layout = mddev->new_layout;
 234	l->new_chunk_sectors = mddev->new_chunk_sectors;
 235}
 236
 237static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)
 238{
 239	struct mddev *mddev = &rs->md;
 240
 241	mddev->new_level = l->new_level;
 242	mddev->new_layout = l->new_layout;
 243	mddev->new_chunk_sectors = l->new_chunk_sectors;
 244}
 245
 246/* raid10 algorithms (i.e. formats) */
 247#define	ALGORITHM_RAID10_DEFAULT	0
 248#define	ALGORITHM_RAID10_NEAR		1
 249#define	ALGORITHM_RAID10_OFFSET		2
 250#define	ALGORITHM_RAID10_FAR		3
 251
 252/* Supported raid types and properties. */
 253static struct raid_type {
 254	const char *name;		/* RAID algorithm. */
 255	const char *descr;		/* Descriptor text for logging. */
 256	const unsigned int parity_devs;	/* # of parity devices. */
 257	const unsigned int minimal_devs;/* minimal # of devices in set. */
 258	const unsigned int level;	/* RAID level. */
 259	const unsigned int algorithm;	/* RAID algorithm. */
 260} raid_types[] = {
 261	{"raid0",	  "raid0 (striping)",			    0, 2, 0,  0 /* NONE */},
 262	{"raid1",	  "raid1 (mirroring)",			    0, 2, 1,  0 /* NONE */},
 263	{"raid10_far",	  "raid10 far (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_FAR},
 264	{"raid10_offset", "raid10 offset (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_OFFSET},
 265	{"raid10_near",	  "raid10 near (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_NEAR},
 266	{"raid10",	  "raid10 (striped mirrors)",		    0, 2, 10, ALGORITHM_RAID10_DEFAULT},
 267	{"raid4",	  "raid4 (dedicated first parity disk)",    1, 2, 5,  ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */
 268	{"raid5_n",	  "raid5 (dedicated last parity disk)",	    1, 2, 5,  ALGORITHM_PARITY_N},
 269	{"raid5_ls",	  "raid5 (left symmetric)",		    1, 2, 5,  ALGORITHM_LEFT_SYMMETRIC},
 270	{"raid5_rs",	  "raid5 (right symmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_SYMMETRIC},
 271	{"raid5_la",	  "raid5 (left asymmetric)",		    1, 2, 5,  ALGORITHM_LEFT_ASYMMETRIC},
 272	{"raid5_ra",	  "raid5 (right asymmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_ASYMMETRIC},
 273	{"raid6_zr",	  "raid6 (zero restart)",		    2, 4, 6,  ALGORITHM_ROTATING_ZERO_RESTART},
 274	{"raid6_nr",	  "raid6 (N restart)",			    2, 4, 6,  ALGORITHM_ROTATING_N_RESTART},
 275	{"raid6_nc",	  "raid6 (N continue)",			    2, 4, 6,  ALGORITHM_ROTATING_N_CONTINUE},
 276	{"raid6_n_6",	  "raid6 (dedicated parity/Q n/6)",	    2, 4, 6,  ALGORITHM_PARITY_N_6},
 277	{"raid6_ls_6",	  "raid6 (left symmetric dedicated Q 6)",   2, 4, 6,  ALGORITHM_LEFT_SYMMETRIC_6},
 278	{"raid6_rs_6",	  "raid6 (right symmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_RIGHT_SYMMETRIC_6},
 279	{"raid6_la_6",	  "raid6 (left asymmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_LEFT_ASYMMETRIC_6},
 280	{"raid6_ra_6",	  "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6,  ALGORITHM_RIGHT_ASYMMETRIC_6}
 281};
 282
 283/* True, if @v is in inclusive range [@min, @max] */
 284static bool __within_range(long v, long min, long max)
 285{
 286	return v >= min && v <= max;
 287}
 288
 289/* All table line arguments are defined here */
 290static struct arg_name_flag {
 291	const unsigned long flag;
 292	const char *name;
 293} __arg_name_flags[] = {
 294	{ CTR_FLAG_SYNC, "sync"},
 295	{ CTR_FLAG_NOSYNC, "nosync"},
 296	{ CTR_FLAG_REBUILD, "rebuild"},
 297	{ CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
 298	{ CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
 299	{ CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
 300	{ CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
 301	{ CTR_FLAG_WRITE_MOSTLY, "write_mostly"},
 302	{ CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
 303	{ CTR_FLAG_REGION_SIZE, "region_size"},
 304	{ CTR_FLAG_RAID10_COPIES, "raid10_copies"},
 305	{ CTR_FLAG_RAID10_FORMAT, "raid10_format"},
 306	{ CTR_FLAG_DATA_OFFSET, "data_offset"},
 307	{ CTR_FLAG_DELTA_DISKS, "delta_disks"},
 308	{ CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
 
 
 309};
 310
 311/* Return argument name string for given @flag */
 312static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
 313{
 314	if (hweight32(flag) == 1) {
 315		struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
 316
 317		while (anf-- > __arg_name_flags)
 318			if (flag & anf->flag)
 319				return anf->name;
 320
 321	} else
 322		DMERR("%s called with more than one flag!", __func__);
 323
 324	return NULL;
 325}
 326
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 327/*
 328 * Bool helpers to test for various raid levels of a raid set.
 329 * It's level as reported by the superblock rather than
 330 * the requested raid_type passed to the constructor.
 331 */
 332/* Return true, if raid set in @rs is raid0 */
 333static bool rs_is_raid0(struct raid_set *rs)
 334{
 335	return !rs->md.level;
 336}
 337
 338/* Return true, if raid set in @rs is raid1 */
 339static bool rs_is_raid1(struct raid_set *rs)
 340{
 341	return rs->md.level == 1;
 342}
 343
 344/* Return true, if raid set in @rs is raid10 */
 345static bool rs_is_raid10(struct raid_set *rs)
 346{
 347	return rs->md.level == 10;
 348}
 349
 350/* Return true, if raid set in @rs is level 6 */
 351static bool rs_is_raid6(struct raid_set *rs)
 352{
 353	return rs->md.level == 6;
 354}
 355
 356/* Return true, if raid set in @rs is level 4, 5 or 6 */
 357static bool rs_is_raid456(struct raid_set *rs)
 358{
 359	return __within_range(rs->md.level, 4, 6);
 360}
 361
 362/* Return true, if raid set in @rs is reshapable */
 363static bool __is_raid10_far(int layout);
 364static bool rs_is_reshapable(struct raid_set *rs)
 365{
 366	return rs_is_raid456(rs) ||
 367	       (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
 368}
 369
 370/* Return true, if raid set in @rs is recovering */
 371static bool rs_is_recovering(struct raid_set *rs)
 372{
 373	return rs->md.recovery_cp < rs->dev[0].rdev.sectors;
 374}
 375
 376/* Return true, if raid set in @rs is reshaping */
 377static bool rs_is_reshaping(struct raid_set *rs)
 378{
 379	return rs->md.reshape_position != MaxSector;
 380}
 381
 382/*
 383 * bool helpers to test for various raid levels of a raid type @rt
 384 */
 385
 386/* Return true, if raid type in @rt is raid0 */
 387static bool rt_is_raid0(struct raid_type *rt)
 388{
 389	return !rt->level;
 390}
 391
 392/* Return true, if raid type in @rt is raid1 */
 393static bool rt_is_raid1(struct raid_type *rt)
 394{
 395	return rt->level == 1;
 396}
 397
 398/* Return true, if raid type in @rt is raid10 */
 399static bool rt_is_raid10(struct raid_type *rt)
 400{
 401	return rt->level == 10;
 402}
 403
 404/* Return true, if raid type in @rt is raid4/5 */
 405static bool rt_is_raid45(struct raid_type *rt)
 406{
 407	return __within_range(rt->level, 4, 5);
 408}
 409
 410/* Return true, if raid type in @rt is raid6 */
 411static bool rt_is_raid6(struct raid_type *rt)
 412{
 413	return rt->level == 6;
 414}
 415
 416/* Return true, if raid type in @rt is raid4/5/6 */
 417static bool rt_is_raid456(struct raid_type *rt)
 418{
 419	return __within_range(rt->level, 4, 6);
 420}
 421/* END: raid level bools */
 422
 423/* Return valid ctr flags for the raid level of @rs */
 424static unsigned long __valid_flags(struct raid_set *rs)
 425{
 426	if (rt_is_raid0(rs->raid_type))
 427		return RAID0_VALID_FLAGS;
 428	else if (rt_is_raid1(rs->raid_type))
 429		return RAID1_VALID_FLAGS;
 430	else if (rt_is_raid10(rs->raid_type))
 431		return RAID10_VALID_FLAGS;
 432	else if (rt_is_raid45(rs->raid_type))
 433		return RAID45_VALID_FLAGS;
 434	else if (rt_is_raid6(rs->raid_type))
 435		return RAID6_VALID_FLAGS;
 436
 437	return 0;
 438}
 439
 440/*
 441 * Check for valid flags set on @rs
 442 *
 443 * Has to be called after parsing of the ctr flags!
 444 */
 445static int rs_check_for_valid_flags(struct raid_set *rs)
 446{
 447	if (rs->ctr_flags & ~__valid_flags(rs)) {
 448		rs->ti->error = "Invalid flags combination";
 449		return -EINVAL;
 450	}
 451
 452	return 0;
 453}
 454
 455/* MD raid10 bit definitions and helpers */
 456#define RAID10_OFFSET			(1 << 16) /* stripes with data copies area adjacent on devices */
 457#define RAID10_BROCKEN_USE_FAR_SETS	(1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
 458#define RAID10_USE_FAR_SETS		(1 << 18) /* Use sets instead of whole stripe rotation */
 459#define RAID10_FAR_COPIES_SHIFT		8	  /* raid10 # far copies shift (2nd byte of layout) */
 460
 461/* Return md raid10 near copies for @layout */
 462static unsigned int __raid10_near_copies(int layout)
 463{
 464	return layout & 0xFF;
 465}
 466
 467/* Return md raid10 far copies for @layout */
 468static unsigned int __raid10_far_copies(int layout)
 469{
 470	return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
 471}
 472
 473/* Return true if md raid10 offset for @layout */
 474static bool __is_raid10_offset(int layout)
 475{
 476	return !!(layout & RAID10_OFFSET);
 477}
 478
 479/* Return true if md raid10 near for @layout */
 480static bool __is_raid10_near(int layout)
 481{
 482	return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
 483}
 484
 485/* Return true if md raid10 far for @layout */
 486static bool __is_raid10_far(int layout)
 487{
 488	return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
 489}
 490
 491/* Return md raid10 layout string for @layout */
 492static const char *raid10_md_layout_to_format(int layout)
 493{
 494	/*
 495	 * Bit 16 stands for "offset"
 496	 * (i.e. adjacent stripes hold copies)
 497	 *
 498	 * Refer to MD's raid10.c for details
 499	 */
 500	if (__is_raid10_offset(layout))
 501		return "offset";
 502
 503	if (__raid10_near_copies(layout) > 1)
 504		return "near";
 505
 506	WARN_ON(__raid10_far_copies(layout) < 2);
 
 507
 508	return "far";
 509}
 510
 511/* Return md raid10 algorithm for @name */
 512static int raid10_name_to_format(const char *name)
 513{
 514	if (!strcasecmp(name, "near"))
 515		return ALGORITHM_RAID10_NEAR;
 516	else if (!strcasecmp(name, "offset"))
 517		return ALGORITHM_RAID10_OFFSET;
 518	else if (!strcasecmp(name, "far"))
 519		return ALGORITHM_RAID10_FAR;
 520
 521	return -EINVAL;
 522}
 523
 524/* Return md raid10 copies for @layout */
 525static unsigned int raid10_md_layout_to_copies(int layout)
 526{
 527	return max(__raid10_near_copies(layout), __raid10_far_copies(layout));
 528}
 529
 530/* Return md raid10 format id for @format string */
 531static int raid10_format_to_md_layout(struct raid_set *rs,
 532				      unsigned int algorithm,
 533				      unsigned int copies)
 534{
 535	unsigned int n = 1, f = 1, r = 0;
 536
 537	/*
 538	 * MD resilienece flaw:
 539	 *
 540	 * enabling use_far_sets for far/offset formats causes copies
 541	 * to be colocated on the same devs together with their origins!
 542	 *
 543	 * -> disable it for now in the definition above
 544	 */
 545	if (algorithm == ALGORITHM_RAID10_DEFAULT ||
 546	    algorithm == ALGORITHM_RAID10_NEAR)
 547		n = copies;
 548
 549	else if (algorithm == ALGORITHM_RAID10_OFFSET) {
 550		f = copies;
 551		r = RAID10_OFFSET;
 552		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 553			r |= RAID10_USE_FAR_SETS;
 554
 555	} else if (algorithm == ALGORITHM_RAID10_FAR) {
 556		f = copies;
 557		r = !RAID10_OFFSET;
 558		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 559			r |= RAID10_USE_FAR_SETS;
 560
 561	} else
 562		return -EINVAL;
 563
 564	return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
 565}
 566/* END: MD raid10 bit definitions and helpers */
 567
 568/* Check for any of the raid10 algorithms */
 569static bool __got_raid10(struct raid_type *rtp, const int layout)
 570{
 571	if (rtp->level == 10) {
 572		switch (rtp->algorithm) {
 573		case ALGORITHM_RAID10_DEFAULT:
 574		case ALGORITHM_RAID10_NEAR:
 575			return __is_raid10_near(layout);
 576		case ALGORITHM_RAID10_OFFSET:
 577			return __is_raid10_offset(layout);
 578		case ALGORITHM_RAID10_FAR:
 579			return __is_raid10_far(layout);
 580		default:
 581			break;
 582		}
 583	}
 584
 585	return false;
 586}
 587
 588/* Return raid_type for @name */
 589static struct raid_type *get_raid_type(const char *name)
 590{
 591	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 592
 593	while (rtp-- > raid_types)
 594		if (!strcasecmp(rtp->name, name))
 595			return rtp;
 596
 597	return NULL;
 598}
 599
 600/* Return raid_type for @name based derived from @level and @layout */
 601static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
 602{
 603	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 604
 605	while (rtp-- > raid_types) {
 606		/* RAID10 special checks based on @layout flags/properties */
 607		if (rtp->level == level &&
 608		    (__got_raid10(rtp, layout) || rtp->algorithm == layout))
 609			return rtp;
 610	}
 611
 612	return NULL;
 613}
 614
 615/*
 616 * Conditionally change bdev capacity of @rs
 617 * in case of a disk add/remove reshape
 618 */
 619static void rs_set_capacity(struct raid_set *rs)
 620{
 621	struct mddev *mddev = &rs->md;
 622	struct md_rdev *rdev;
 623	struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
 624
 625	/*
 626	 * raid10 sets rdev->sector to the device size, which
 627	 * is unintended in case of out-of-place reshaping
 628	 */
 629	rdev_for_each(rdev, mddev)
 630		rdev->sectors = mddev->dev_sectors;
 
 
 631
 632	set_capacity(gendisk, mddev->array_sectors);
 633	revalidate_disk(gendisk);
 
 
 
 
 
 
 634}
 635
 636/*
 637 * Set the mddev properties in @rs to the current
 638 * ones retrieved from the freshest superblock
 639 */
 640static void rs_set_cur(struct raid_set *rs)
 641{
 642	struct mddev *mddev = &rs->md;
 643
 644	mddev->new_level = mddev->level;
 645	mddev->new_layout = mddev->layout;
 646	mddev->new_chunk_sectors = mddev->chunk_sectors;
 647}
 648
 649/*
 650 * Set the mddev properties in @rs to the new
 651 * ones requested by the ctr
 652 */
 653static void rs_set_new(struct raid_set *rs)
 654{
 655	struct mddev *mddev = &rs->md;
 656
 657	mddev->level = mddev->new_level;
 658	mddev->layout = mddev->new_layout;
 659	mddev->chunk_sectors = mddev->new_chunk_sectors;
 660	mddev->raid_disks = rs->raid_disks;
 661	mddev->delta_disks = 0;
 662}
 663
 664static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
 665				       unsigned int raid_devs)
 666{
 667	unsigned int i;
 668	struct raid_set *rs;
 669
 670	if (raid_devs <= raid_type->parity_devs) {
 671		ti->error = "Insufficient number of devices";
 672		return ERR_PTR(-EINVAL);
 673	}
 674
 675	rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL);
 676	if (!rs) {
 677		ti->error = "Cannot allocate raid context";
 678		return ERR_PTR(-ENOMEM);
 679	}
 680
 681	mddev_init(&rs->md);
 
 
 
 
 682
 683	rs->raid_disks = raid_devs;
 684	rs->delta_disks = 0;
 685
 686	rs->ti = ti;
 687	rs->raid_type = raid_type;
 688	rs->stripe_cache_entries = 256;
 689	rs->md.raid_disks = raid_devs;
 690	rs->md.level = raid_type->level;
 691	rs->md.new_level = rs->md.level;
 692	rs->md.layout = raid_type->algorithm;
 693	rs->md.new_layout = rs->md.layout;
 694	rs->md.delta_disks = 0;
 695	rs->md.recovery_cp = MaxSector;
 696
 697	for (i = 0; i < raid_devs; i++)
 698		md_rdev_init(&rs->dev[i].rdev);
 699
 700	/*
 701	 * Remaining items to be initialized by further RAID params:
 702	 *  rs->md.persistent
 703	 *  rs->md.external
 704	 *  rs->md.chunk_sectors
 705	 *  rs->md.new_chunk_sectors
 706	 *  rs->md.dev_sectors
 707	 */
 708
 709	return rs;
 710}
 711
 
 712static void raid_set_free(struct raid_set *rs)
 713{
 714	int i;
 715
 
 
 
 
 
 716	for (i = 0; i < rs->raid_disks; i++) {
 717		if (rs->dev[i].meta_dev)
 718			dm_put_device(rs->ti, rs->dev[i].meta_dev);
 719		md_rdev_clear(&rs->dev[i].rdev);
 720		if (rs->dev[i].data_dev)
 721			dm_put_device(rs->ti, rs->dev[i].data_dev);
 722	}
 723
 
 724	kfree(rs);
 725}
 726
 727/*
 728 * For every device we have two words
 729 *  <meta_dev>: meta device name or '-' if missing
 730 *  <data_dev>: data device name or '-' if missing
 731 *
 732 * The following are permitted:
 733 *    - -
 734 *    - <data_dev>
 735 *    <meta_dev> <data_dev>
 736 *
 737 * The following is not allowed:
 738 *    <meta_dev> -
 739 *
 740 * This code parses those words.  If there is a failure,
 741 * the caller must use raid_set_free() to unwind the operations.
 742 */
 743static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
 744{
 745	int i;
 746	int rebuild = 0;
 747	int metadata_available = 0;
 748	int r = 0;
 749	const char *arg;
 750
 751	/* Put off the number of raid devices argument to get to dev pairs */
 752	arg = dm_shift_arg(as);
 753	if (!arg)
 754		return -EINVAL;
 755
 756	for (i = 0; i < rs->raid_disks; i++) {
 757		rs->dev[i].rdev.raid_disk = i;
 758
 759		rs->dev[i].meta_dev = NULL;
 760		rs->dev[i].data_dev = NULL;
 761
 762		/*
 763		 * There are no offsets, since there is a separate device
 764		 * for data and metadata.
 765		 */
 766		rs->dev[i].rdev.data_offset = 0;
 
 767		rs->dev[i].rdev.mddev = &rs->md;
 768
 769		arg = dm_shift_arg(as);
 770		if (!arg)
 771			return -EINVAL;
 772
 773		if (strcmp(arg, "-")) {
 774			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 775					  &rs->dev[i].meta_dev);
 776			if (r) {
 777				rs->ti->error = "RAID metadata device lookup failure";
 778				return r;
 779			}
 780
 781			rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
 782			if (!rs->dev[i].rdev.sb_page) {
 783				rs->ti->error = "Failed to allocate superblock page";
 784				return -ENOMEM;
 785			}
 786		}
 787
 788		arg = dm_shift_arg(as);
 789		if (!arg)
 790			return -EINVAL;
 791
 792		if (!strcmp(arg, "-")) {
 793			if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
 794			    (!rs->dev[i].rdev.recovery_offset)) {
 795				rs->ti->error = "Drive designated for rebuild not specified";
 796				return -EINVAL;
 797			}
 798
 799			if (rs->dev[i].meta_dev) {
 800				rs->ti->error = "No data device supplied with metadata device";
 801				return -EINVAL;
 802			}
 803
 804			continue;
 805		}
 806
 807		r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 808				  &rs->dev[i].data_dev);
 809		if (r) {
 810			rs->ti->error = "RAID device lookup failure";
 811			return r;
 812		}
 813
 814		if (rs->dev[i].meta_dev) {
 815			metadata_available = 1;
 816			rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
 817		}
 818		rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
 819		list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
 820		if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
 821			rebuild++;
 822	}
 823
 
 
 
 824	if (metadata_available) {
 825		rs->md.external = 0;
 826		rs->md.persistent = 1;
 827		rs->md.major_version = 2;
 828	} else if (rebuild && !rs->md.recovery_cp) {
 829		/*
 830		 * Without metadata, we will not be able to tell if the array
 831		 * is in-sync or not - we must assume it is not.  Therefore,
 832		 * it is impossible to rebuild a drive.
 833		 *
 834		 * Even if there is metadata, the on-disk information may
 835		 * indicate that the array is not in-sync and it will then
 836		 * fail at that time.
 837		 *
 838		 * User could specify 'nosync' option if desperate.
 839		 */
 840		rs->ti->error = "Unable to rebuild drive while array is not in-sync";
 841		return -EINVAL;
 842	}
 843
 844	return 0;
 845}
 846
 847/*
 848 * validate_region_size
 849 * @rs
 850 * @region_size:  region size in sectors.  If 0, pick a size (4MiB default).
 851 *
 852 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
 853 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
 854 *
 855 * Returns: 0 on success, -EINVAL on failure.
 856 */
 857static int validate_region_size(struct raid_set *rs, unsigned long region_size)
 858{
 859	unsigned long min_region_size = rs->ti->len / (1 << 21);
 860
 861	if (rs_is_raid0(rs))
 862		return 0;
 863
 864	if (!region_size) {
 865		/*
 866		 * Choose a reasonable default.	 All figures in sectors.
 867		 */
 868		if (min_region_size > (1 << 13)) {
 869			/* If not a power of 2, make it the next power of 2 */
 870			region_size = roundup_pow_of_two(min_region_size);
 871			DMINFO("Choosing default region size of %lu sectors",
 872			       region_size);
 873		} else {
 874			DMINFO("Choosing default region size of 4MiB");
 875			region_size = 1 << 13; /* sectors */
 876		}
 877	} else {
 878		/*
 879		 * Validate user-supplied value.
 880		 */
 881		if (region_size > rs->ti->len) {
 882			rs->ti->error = "Supplied region size is too large";
 883			return -EINVAL;
 884		}
 885
 886		if (region_size < min_region_size) {
 887			DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
 888			      region_size, min_region_size);
 889			rs->ti->error = "Supplied region size is too small";
 890			return -EINVAL;
 891		}
 892
 893		if (!is_power_of_2(region_size)) {
 894			rs->ti->error = "Region size is not a power of 2";
 895			return -EINVAL;
 896		}
 897
 898		if (region_size < rs->md.chunk_sectors) {
 899			rs->ti->error = "Region size is smaller than the chunk size";
 900			return -EINVAL;
 901		}
 902	}
 903
 904	/*
 905	 * Convert sectors to bytes.
 906	 */
 907	rs->md.bitmap_info.chunksize = to_bytes(region_size);
 908
 909	return 0;
 910}
 911
 912/*
 913 * validate_raid_redundancy
 914 * @rs
 915 *
 916 * Determine if there are enough devices in the array that haven't
 917 * failed (or are being rebuilt) to form a usable array.
 918 *
 919 * Returns: 0 on success, -EINVAL on failure.
 920 */
 921static int validate_raid_redundancy(struct raid_set *rs)
 922{
 923	unsigned int i, rebuild_cnt = 0;
 924	unsigned int rebuilds_per_group = 0, copies;
 925	unsigned int group_size, last_group_start;
 926
 927	for (i = 0; i < rs->md.raid_disks; i++)
 928		if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
 929		    !rs->dev[i].rdev.sb_page)
 
 930			rebuild_cnt++;
 931
 932	switch (rs->raid_type->level) {
 933	case 0:
 934		break;
 935	case 1:
 936		if (rebuild_cnt >= rs->md.raid_disks)
 937			goto too_many;
 938		break;
 939	case 4:
 940	case 5:
 941	case 6:
 942		if (rebuild_cnt > rs->raid_type->parity_devs)
 943			goto too_many;
 944		break;
 945	case 10:
 946		copies = raid10_md_layout_to_copies(rs->md.new_layout);
 
 
 
 
 
 947		if (rebuild_cnt < copies)
 948			break;
 949
 950		/*
 951		 * It is possible to have a higher rebuild count for RAID10,
 952		 * as long as the failed devices occur in different mirror
 953		 * groups (i.e. different stripes).
 954		 *
 955		 * When checking "near" format, make sure no adjacent devices
 956		 * have failed beyond what can be handled.  In addition to the
 957		 * simple case where the number of devices is a multiple of the
 958		 * number of copies, we must also handle cases where the number
 959		 * of devices is not a multiple of the number of copies.
 960		 * E.g.	   dev1 dev2 dev3 dev4 dev5
 961		 *	    A	 A    B	   B	C
 962		 *	    C	 D    D	   E	E
 963		 */
 
 964		if (__is_raid10_near(rs->md.new_layout)) {
 965			for (i = 0; i < rs->md.raid_disks; i++) {
 966				if (!(i % copies))
 967					rebuilds_per_group = 0;
 968				if ((!rs->dev[i].rdev.sb_page ||
 969				    !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
 970				    (++rebuilds_per_group >= copies))
 971					goto too_many;
 972			}
 973			break;
 974		}
 975
 976		/*
 977		 * When checking "far" and "offset" formats, we need to ensure
 978		 * that the device that holds its copy is not also dead or
 979		 * being rebuilt.  (Note that "far" and "offset" formats only
 980		 * support two copies right now.  These formats also only ever
 981		 * use the 'use_far_sets' variant.)
 982		 *
 983		 * This check is somewhat complicated by the need to account
 984		 * for arrays that are not a multiple of (far) copies.	This
 985		 * results in the need to treat the last (potentially larger)
 986		 * set differently.
 987		 */
 988		group_size = (rs->md.raid_disks / copies);
 989		last_group_start = (rs->md.raid_disks / group_size) - 1;
 990		last_group_start *= group_size;
 991		for (i = 0; i < rs->md.raid_disks; i++) {
 992			if (!(i % copies) && !(i > last_group_start))
 993				rebuilds_per_group = 0;
 994			if ((!rs->dev[i].rdev.sb_page ||
 995			     !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
 996			    (++rebuilds_per_group >= copies))
 997					goto too_many;
 998		}
 999		break;
1000	default:
1001		if (rebuild_cnt)
1002			return -EINVAL;
1003	}
1004
1005	return 0;
1006
1007too_many:
1008	return -EINVAL;
1009}
1010
1011/*
1012 * Possible arguments are...
1013 *	<chunk_size> [optional_args]
1014 *
1015 * Argument definitions
1016 *    <chunk_size>			The number of sectors per disk that
1017 *					will form the "stripe"
1018 *    [[no]sync]			Force or prevent recovery of the
1019 *					entire array
1020 *    [rebuild <idx>]			Rebuild the drive indicated by the index
1021 *    [daemon_sleep <ms>]		Time between bitmap daemon work to
1022 *					clear bits
1023 *    [min_recovery_rate <kB/sec/disk>]	Throttle RAID initialization
1024 *    [max_recovery_rate <kB/sec/disk>]	Throttle RAID initialization
1025 *    [write_mostly <idx>]		Indicate a write mostly drive via index
1026 *    [max_write_behind <sectors>]	See '-write-behind=' (man mdadm)
1027 *    [stripe_cache <sectors>]		Stripe cache size for higher RAIDs
1028 *    [region_size <sectors>]		Defines granularity of bitmap
 
 
1029 *
1030 * RAID10-only options:
1031 *    [raid10_copies <# copies>]	Number of copies.  (Default: 2)
1032 *    [raid10_format <near|far|offset>] Layout algorithm.  (Default: near)
1033 */
1034static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
1035			     unsigned int num_raid_params)
1036{
1037	int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
1038	unsigned int raid10_copies = 2;
1039	unsigned int i, write_mostly = 0;
1040	unsigned int region_size = 0;
1041	sector_t max_io_len;
1042	const char *arg, *key;
1043	struct raid_dev *rd;
1044	struct raid_type *rt = rs->raid_type;
1045
1046	arg = dm_shift_arg(as);
1047	num_raid_params--; /* Account for chunk_size argument */
1048
1049	if (kstrtoint(arg, 10, &value) < 0) {
1050		rs->ti->error = "Bad numerical argument given for chunk_size";
1051		return -EINVAL;
1052	}
1053
1054	/*
1055	 * First, parse the in-order required arguments
1056	 * "chunk_size" is the only argument of this type.
1057	 */
1058	if (rt_is_raid1(rt)) {
1059		if (value)
1060			DMERR("Ignoring chunk size parameter for RAID 1");
1061		value = 0;
1062	} else if (!is_power_of_2(value)) {
1063		rs->ti->error = "Chunk size must be a power of 2";
1064		return -EINVAL;
1065	} else if (value < 8) {
1066		rs->ti->error = "Chunk size value is too small";
1067		return -EINVAL;
1068	}
1069
1070	rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1071
1072	/*
1073	 * We set each individual device as In_sync with a completed
1074	 * 'recovery_offset'.  If there has been a device failure or
1075	 * replacement then one of the following cases applies:
1076	 *
1077	 *   1) User specifies 'rebuild'.
1078	 *	- Device is reset when param is read.
1079	 *   2) A new device is supplied.
1080	 *	- No matching superblock found, resets device.
1081	 *   3) Device failure was transient and returns on reload.
1082	 *	- Failure noticed, resets device for bitmap replay.
1083	 *   4) Device hadn't completed recovery after previous failure.
1084	 *	- Superblock is read and overrides recovery_offset.
1085	 *
1086	 * What is found in the superblocks of the devices is always
1087	 * authoritative, unless 'rebuild' or '[no]sync' was specified.
1088	 */
1089	for (i = 0; i < rs->raid_disks; i++) {
1090		set_bit(In_sync, &rs->dev[i].rdev.flags);
1091		rs->dev[i].rdev.recovery_offset = MaxSector;
1092	}
1093
1094	/*
1095	 * Second, parse the unordered optional arguments
1096	 */
1097	for (i = 0; i < num_raid_params; i++) {
1098		key = dm_shift_arg(as);
1099		if (!key) {
1100			rs->ti->error = "Not enough raid parameters given";
1101			return -EINVAL;
1102		}
1103
1104		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1105			if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1106				rs->ti->error = "Only one 'nosync' argument allowed";
1107				return -EINVAL;
1108			}
1109			continue;
1110		}
1111		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1112			if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1113				rs->ti->error = "Only one 'sync' argument allowed";
1114				return -EINVAL;
1115			}
1116			continue;
1117		}
1118		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1119			if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1120				rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1121				return -EINVAL;
1122			}
1123			continue;
1124		}
1125
1126		arg = dm_shift_arg(as);
1127		i++; /* Account for the argument pairs */
1128		if (!arg) {
1129			rs->ti->error = "Wrong number of raid parameters given";
1130			return -EINVAL;
1131		}
1132
1133		/*
1134		 * Parameters that take a string value are checked here.
1135		 */
1136
1137		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1138			if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1139				rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1140				return -EINVAL;
1141			}
1142			if (!rt_is_raid10(rt)) {
1143				rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1144				return -EINVAL;
1145			}
1146			raid10_format = raid10_name_to_format(arg);
1147			if (raid10_format < 0) {
1148				rs->ti->error = "Invalid 'raid10_format' value given";
1149				return raid10_format;
1150			}
1151			continue;
1152		}
1153
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1154		if (kstrtoint(arg, 10, &value) < 0) {
1155			rs->ti->error = "Bad numerical argument given in raid params";
1156			return -EINVAL;
1157		}
1158
1159		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1160			/*
1161			 * "rebuild" is being passed in by userspace to provide
1162			 * indexes of replaced devices and to set up additional
1163			 * devices on raid level takeover.
1164			 */
1165			if (!__within_range(value, 0, rs->raid_disks - 1)) {
1166				rs->ti->error = "Invalid rebuild index given";
1167				return -EINVAL;
1168			}
1169
1170			if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1171				rs->ti->error = "rebuild for this index already given";
1172				return -EINVAL;
1173			}
1174
1175			rd = rs->dev + value;
1176			clear_bit(In_sync, &rd->rdev.flags);
1177			clear_bit(Faulty, &rd->rdev.flags);
1178			rd->rdev.recovery_offset = 0;
1179			set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1180		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1181			if (!rt_is_raid1(rt)) {
1182				rs->ti->error = "write_mostly option is only valid for RAID1";
1183				return -EINVAL;
1184			}
1185
1186			if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1187				rs->ti->error = "Invalid write_mostly index given";
1188				return -EINVAL;
1189			}
1190
1191			write_mostly++;
1192			set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1193			set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1194		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1195			if (!rt_is_raid1(rt)) {
1196				rs->ti->error = "max_write_behind option is only valid for RAID1";
1197				return -EINVAL;
1198			}
1199
1200			if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1201				rs->ti->error = "Only one max_write_behind argument pair allowed";
1202				return -EINVAL;
1203			}
1204
1205			/*
1206			 * In device-mapper, we specify things in sectors, but
1207			 * MD records this value in kB
1208			 */
1209			value /= 2;
1210			if (value > COUNTER_MAX) {
1211				rs->ti->error = "Max write-behind limit out of range";
1212				return -EINVAL;
1213			}
1214
1215			rs->md.bitmap_info.max_write_behind = value;
1216		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1217			if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1218				rs->ti->error = "Only one daemon_sleep argument pair allowed";
1219				return -EINVAL;
1220			}
1221			if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
1222				rs->ti->error = "daemon sleep period out of range";
1223				return -EINVAL;
1224			}
1225			rs->md.bitmap_info.daemon_sleep = value;
1226		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1227			/* Userspace passes new data_offset after having extended the the data image LV */
1228			if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1229				rs->ti->error = "Only one data_offset argument pair allowed";
1230				return -EINVAL;
1231			}
1232			/* Ensure sensible data offset */
1233			if (value < 0 ||
1234			    (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {
1235				rs->ti->error = "Bogus data_offset value";
1236				return -EINVAL;
1237			}
1238			rs->data_offset = value;
1239		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1240			/* Define the +/-# of disks to add to/remove from the given raid set */
1241			if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1242				rs->ti->error = "Only one delta_disks argument pair allowed";
1243				return -EINVAL;
1244			}
1245			/* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1246			if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1247				rs->ti->error = "Too many delta_disk requested";
1248				return -EINVAL;
1249			}
1250
1251			rs->delta_disks = value;
1252		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1253			if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1254				rs->ti->error = "Only one stripe_cache argument pair allowed";
1255				return -EINVAL;
1256			}
1257
1258			if (!rt_is_raid456(rt)) {
1259				rs->ti->error = "Inappropriate argument: stripe_cache";
1260				return -EINVAL;
1261			}
1262
 
 
 
 
1263			rs->stripe_cache_entries = value;
1264		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1265			if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1266				rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1267				return -EINVAL;
1268			}
1269			if (value > INT_MAX) {
 
1270				rs->ti->error = "min_recovery_rate out of range";
1271				return -EINVAL;
1272			}
1273			rs->md.sync_speed_min = (int)value;
1274		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1275			if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
1276				rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1277				return -EINVAL;
1278			}
1279			if (value > INT_MAX) {
 
1280				rs->ti->error = "max_recovery_rate out of range";
1281				return -EINVAL;
1282			}
1283			rs->md.sync_speed_max = (int)value;
1284		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1285			if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1286				rs->ti->error = "Only one region_size argument pair allowed";
1287				return -EINVAL;
1288			}
1289
1290			region_size = value;
1291			rs->requested_bitmap_chunk_sectors = value;
1292		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1293			if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1294				rs->ti->error = "Only one raid10_copies argument pair allowed";
1295				return -EINVAL;
1296			}
1297
1298			if (!__within_range(value, 2, rs->md.raid_disks)) {
1299				rs->ti->error = "Bad value for 'raid10_copies'";
1300				return -EINVAL;
1301			}
1302
1303			raid10_copies = value;
1304		} else {
1305			DMERR("Unable to parse RAID parameter: %s", key);
1306			rs->ti->error = "Unable to parse RAID parameter";
1307			return -EINVAL;
1308		}
1309	}
1310
1311	if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1312	    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1313		rs->ti->error = "sync and nosync are mutually exclusive";
1314		return -EINVAL;
1315	}
1316
1317	if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
1318	    (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
1319	     test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
1320		rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
1321		return -EINVAL;
1322	}
1323
1324	if (write_mostly >= rs->md.raid_disks) {
1325		rs->ti->error = "Can't set all raid1 devices to write_mostly";
1326		return -EINVAL;
1327	}
1328
 
 
 
 
 
 
1329	if (validate_region_size(rs, region_size))
1330		return -EINVAL;
1331
1332	if (rs->md.chunk_sectors)
1333		max_io_len = rs->md.chunk_sectors;
1334	else
1335		max_io_len = region_size;
1336
1337	if (dm_set_target_max_io_len(rs->ti, max_io_len))
1338		return -EINVAL;
1339
1340	if (rt_is_raid10(rt)) {
1341		if (raid10_copies > rs->md.raid_disks) {
1342			rs->ti->error = "Not enough devices to satisfy specification";
1343			return -EINVAL;
1344		}
1345
1346		rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1347		if (rs->md.new_layout < 0) {
1348			rs->ti->error = "Error getting raid10 format";
1349			return rs->md.new_layout;
1350		}
1351
1352		rt = get_raid_type_by_ll(10, rs->md.new_layout);
1353		if (!rt) {
1354			rs->ti->error = "Failed to recognize new raid10 layout";
1355			return -EINVAL;
1356		}
1357
1358		if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1359		     rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1360		    test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1361			rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1362			return -EINVAL;
1363		}
1364	}
1365
1366	rs->raid10_copies = raid10_copies;
1367
1368	/* Assume there are no metadata devices until the drives are parsed */
1369	rs->md.persistent = 0;
1370	rs->md.external = 1;
1371
1372	/* Check, if any invalid ctr arguments have been passed in for the raid level */
1373	return rs_check_for_valid_flags(rs);
1374}
1375
1376/* Set raid4/5/6 cache size */
1377static int rs_set_raid456_stripe_cache(struct raid_set *rs)
1378{
1379	int r;
1380	struct r5conf *conf;
1381	struct mddev *mddev = &rs->md;
1382	uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
1383	uint32_t nr_stripes = rs->stripe_cache_entries;
1384
1385	if (!rt_is_raid456(rs->raid_type)) {
1386		rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
1387		return -EINVAL;
1388	}
1389
1390	if (nr_stripes < min_stripes) {
1391		DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
1392		       nr_stripes, min_stripes);
1393		nr_stripes = min_stripes;
1394	}
1395
1396	conf = mddev->private;
1397	if (!conf) {
1398		rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
1399		return -EINVAL;
1400	}
1401
1402	/* Try setting number of stripes in raid456 stripe cache */
1403	if (conf->min_nr_stripes != nr_stripes) {
1404		r = raid5_set_cache_size(mddev, nr_stripes);
1405		if (r) {
1406			rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
1407			return r;
1408		}
1409
1410		DMINFO("%u stripe cache entries", nr_stripes);
1411	}
1412
1413	return 0;
1414}
1415
1416/* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1417static unsigned int mddev_data_stripes(struct raid_set *rs)
1418{
1419	return rs->md.raid_disks - rs->raid_type->parity_devs;
1420}
1421
1422/* Return # of data stripes of @rs (i.e. as of ctr) */
1423static unsigned int rs_data_stripes(struct raid_set *rs)
1424{
1425	return rs->raid_disks - rs->raid_type->parity_devs;
1426}
1427
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1428/* Calculate the sectors per device and per array used for @rs */
1429static int rs_set_dev_and_array_sectors(struct raid_set *rs, bool use_mddev)
1430{
1431	int delta_disks;
1432	unsigned int data_stripes;
 
1433	struct mddev *mddev = &rs->md;
1434	struct md_rdev *rdev;
1435	sector_t array_sectors = rs->ti->len, dev_sectors = rs->ti->len;
1436
1437	if (use_mddev) {
1438		delta_disks = mddev->delta_disks;
1439		data_stripes = mddev_data_stripes(rs);
1440	} else {
1441		delta_disks = rs->delta_disks;
1442		data_stripes = rs_data_stripes(rs);
1443	}
1444
1445	/* Special raid1 case w/o delta_disks support (yet) */
1446	if (rt_is_raid1(rs->raid_type))
1447		;
1448	else if (rt_is_raid10(rs->raid_type)) {
1449		if (rs->raid10_copies < 2 ||
1450		    delta_disks < 0) {
1451			rs->ti->error = "Bogus raid10 data copies or delta disks";
1452			return -EINVAL;
1453		}
1454
1455		dev_sectors *= rs->raid10_copies;
1456		if (sector_div(dev_sectors, data_stripes))
1457			goto bad;
1458
1459		array_sectors = (data_stripes + delta_disks) * dev_sectors;
1460		if (sector_div(array_sectors, rs->raid10_copies))
1461			goto bad;
1462
1463	} else if (sector_div(dev_sectors, data_stripes))
1464		goto bad;
1465
1466	else
1467		/* Striped layouts */
1468		array_sectors = (data_stripes + delta_disks) * dev_sectors;
1469
1470	rdev_for_each(rdev, mddev)
1471		rdev->sectors = dev_sectors;
1472
1473	mddev->array_sectors = array_sectors;
1474	mddev->dev_sectors = dev_sectors;
 
1475
1476	return 0;
1477bad:
1478	rs->ti->error = "Target length not divisible by number of data devices";
1479	return -EINVAL;
1480}
1481
1482/* Setup recovery on @rs */
1483static void __rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1484{
1485	/* raid0 does not recover */
1486	if (rs_is_raid0(rs))
1487		rs->md.recovery_cp = MaxSector;
1488	/*
1489	 * A raid6 set has to be recovered either
1490	 * completely or for the grown part to
1491	 * ensure proper parity and Q-Syndrome
1492	 */
1493	else if (rs_is_raid6(rs))
1494		rs->md.recovery_cp = dev_sectors;
1495	/*
1496	 * Other raid set types may skip recovery
1497	 * depending on the 'nosync' flag.
1498	 */
1499	else
1500		rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
1501				     ? MaxSector : dev_sectors;
1502}
1503
1504/* Setup recovery on @rs based on raid type, device size and 'nosync' flag */
1505static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1506{
1507	if (!dev_sectors)
1508		/* New raid set or 'sync' flag provided */
1509		__rs_setup_recovery(rs, 0);
1510	else if (dev_sectors == MaxSector)
1511		/* Prevent recovery */
1512		__rs_setup_recovery(rs, MaxSector);
1513	else if (rs->dev[0].rdev.sectors < dev_sectors)
1514		/* Grown raid set */
1515		__rs_setup_recovery(rs, rs->dev[0].rdev.sectors);
1516	else
1517		__rs_setup_recovery(rs, MaxSector);
1518}
1519
1520static void do_table_event(struct work_struct *ws)
1521{
1522	struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1523
1524	smp_rmb(); /* Make sure we access most actual mddev properties */
1525	if (!rs_is_reshaping(rs))
 
 
1526		rs_set_capacity(rs);
 
1527	dm_table_event(rs->ti->table);
1528}
1529
1530static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
1531{
1532	struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
1533
1534	return mddev_congested(&rs->md, bits);
1535}
1536
1537/*
1538 * Make sure a valid takover (level switch) is being requested on @rs
1539 *
1540 * Conversions of raid sets from one MD personality to another
1541 * have to conform to restrictions which are enforced here.
1542 */
1543static int rs_check_takeover(struct raid_set *rs)
1544{
1545	struct mddev *mddev = &rs->md;
1546	unsigned int near_copies;
1547
1548	if (rs->md.degraded) {
1549		rs->ti->error = "Can't takeover degraded raid set";
1550		return -EPERM;
1551	}
1552
1553	if (rs_is_reshaping(rs)) {
1554		rs->ti->error = "Can't takeover reshaping raid set";
1555		return -EPERM;
1556	}
1557
1558	switch (mddev->level) {
1559	case 0:
1560		/* raid0 -> raid1/5 with one disk */
1561		if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1562		    mddev->raid_disks == 1)
1563			return 0;
1564
1565		/* raid0 -> raid10 */
1566		if (mddev->new_level == 10 &&
1567		    !(rs->raid_disks % mddev->raid_disks))
1568			return 0;
1569
1570		/* raid0 with multiple disks -> raid4/5/6 */
1571		if (__within_range(mddev->new_level, 4, 6) &&
1572		    mddev->new_layout == ALGORITHM_PARITY_N &&
1573		    mddev->raid_disks > 1)
1574			return 0;
1575
1576		break;
1577
1578	case 10:
1579		/* Can't takeover raid10_offset! */
1580		if (__is_raid10_offset(mddev->layout))
1581			break;
1582
1583		near_copies = __raid10_near_copies(mddev->layout);
1584
1585		/* raid10* -> raid0 */
1586		if (mddev->new_level == 0) {
1587			/* Can takeover raid10_near with raid disks divisable by data copies! */
1588			if (near_copies > 1 &&
1589			    !(mddev->raid_disks % near_copies)) {
1590				mddev->raid_disks /= near_copies;
1591				mddev->delta_disks = mddev->raid_disks;
1592				return 0;
1593			}
1594
1595			/* Can takeover raid10_far */
1596			if (near_copies == 1 &&
1597			    __raid10_far_copies(mddev->layout) > 1)
1598				return 0;
1599
1600			break;
1601		}
1602
1603		/* raid10_{near,far} -> raid1 */
1604		if (mddev->new_level == 1 &&
1605		    max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1606			return 0;
1607
1608		/* raid10_{near,far} with 2 disks -> raid4/5 */
1609		if (__within_range(mddev->new_level, 4, 5) &&
1610		    mddev->raid_disks == 2)
1611			return 0;
1612		break;
1613
1614	case 1:
1615		/* raid1 with 2 disks -> raid4/5 */
1616		if (__within_range(mddev->new_level, 4, 5) &&
1617		    mddev->raid_disks == 2) {
1618			mddev->degraded = 1;
1619			return 0;
1620		}
1621
1622		/* raid1 -> raid0 */
1623		if (mddev->new_level == 0 &&
1624		    mddev->raid_disks == 1)
1625			return 0;
1626
1627		/* raid1 -> raid10 */
1628		if (mddev->new_level == 10)
1629			return 0;
1630		break;
1631
1632	case 4:
1633		/* raid4 -> raid0 */
1634		if (mddev->new_level == 0)
1635			return 0;
1636
1637		/* raid4 -> raid1/5 with 2 disks */
1638		if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1639		    mddev->raid_disks == 2)
1640			return 0;
1641
1642		/* raid4 -> raid5/6 with parity N */
1643		if (__within_range(mddev->new_level, 5, 6) &&
1644		    mddev->layout == ALGORITHM_PARITY_N)
1645			return 0;
1646		break;
1647
1648	case 5:
1649		/* raid5 with parity N -> raid0 */
1650		if (mddev->new_level == 0 &&
1651		    mddev->layout == ALGORITHM_PARITY_N)
1652			return 0;
1653
1654		/* raid5 with parity N -> raid4 */
1655		if (mddev->new_level == 4 &&
1656		    mddev->layout == ALGORITHM_PARITY_N)
1657			return 0;
1658
1659		/* raid5 with 2 disks -> raid1/4/10 */
1660		if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1661		    mddev->raid_disks == 2)
1662			return 0;
1663
1664		/* raid5_* ->  raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
1665		if (mddev->new_level == 6 &&
1666		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1667		      __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1668			return 0;
1669		break;
1670
1671	case 6:
1672		/* raid6 with parity N -> raid0 */
1673		if (mddev->new_level == 0 &&
1674		    mddev->layout == ALGORITHM_PARITY_N)
1675			return 0;
1676
1677		/* raid6 with parity N -> raid4 */
1678		if (mddev->new_level == 4 &&
1679		    mddev->layout == ALGORITHM_PARITY_N)
1680			return 0;
1681
1682		/* raid6_*_n with Q-Syndrome N -> raid5_* */
1683		if (mddev->new_level == 5 &&
1684		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1685		     __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1686			return 0;
 
1687
1688	default:
1689		break;
1690	}
1691
1692	rs->ti->error = "takeover not possible";
1693	return -EINVAL;
1694}
1695
1696/* True if @rs requested to be taken over */
1697static bool rs_takeover_requested(struct raid_set *rs)
1698{
1699	return rs->md.new_level != rs->md.level;
1700}
1701
 
 
 
 
 
 
 
 
1702/* True if @rs is requested to reshape by ctr */
1703static bool rs_reshape_requested(struct raid_set *rs)
1704{
1705	bool change;
1706	struct mddev *mddev = &rs->md;
1707
1708	if (rs_takeover_requested(rs))
1709		return false;
1710
1711	if (!mddev->level)
1712		return false;
1713
1714	change = mddev->new_layout != mddev->layout ||
1715		 mddev->new_chunk_sectors != mddev->chunk_sectors ||
1716		 rs->delta_disks;
1717
1718	/* Historical case to support raid1 reshape without delta disks */
1719	if (mddev->level == 1) {
1720		if (rs->delta_disks)
1721			return !!rs->delta_disks;
1722
1723		return !change &&
1724		       mddev->raid_disks != rs->raid_disks;
1725	}
1726
1727	if (mddev->level == 10)
1728		return change &&
1729		       !__is_raid10_far(mddev->new_layout) &&
1730		       rs->delta_disks >= 0;
1731
1732	return change;
1733}
1734
1735/*  Features */
1736#define	FEATURE_FLAG_SUPPORTS_V190	0x1 /* Supports extended superblock */
1737
1738/* State flags for sb->flags */
1739#define	SB_FLAG_RESHAPE_ACTIVE		0x1
1740#define	SB_FLAG_RESHAPE_BACKWARDS	0x2
1741
1742/*
1743 * This structure is never routinely used by userspace, unlike md superblocks.
1744 * Devices with this superblock should only ever be accessed via device-mapper.
1745 */
1746#define DM_RAID_MAGIC 0x64526D44
1747struct dm_raid_superblock {
1748	__le32 magic;		/* "DmRd" */
1749	__le32 compat_features;	/* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1750
1751	__le32 num_devices;	/* Number of devices in this raid set. (Max 64) */
1752	__le32 array_position;	/* The position of this drive in the raid set */
1753
1754	__le64 events;		/* Incremented by md when superblock updated */
1755	__le64 failed_devices;	/* Pre 1.9.0 part of bit field of devices to */
1756				/* indicate failures (see extension below) */
1757
1758	/*
1759	 * This offset tracks the progress of the repair or replacement of
1760	 * an individual drive.
1761	 */
1762	__le64 disk_recovery_offset;
1763
1764	/*
1765	 * This offset tracks the progress of the initial raid set
1766	 * synchronisation/parity calculation.
1767	 */
1768	__le64 array_resync_offset;
1769
1770	/*
1771	 * raid characteristics
1772	 */
1773	__le32 level;
1774	__le32 layout;
1775	__le32 stripe_sectors;
1776
1777	/********************************************************************
1778	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1779	 *
1780	 * FEATURE_FLAG_SUPPORTS_V190 in the features member indicates that those exist
1781	 */
1782
1783	__le32 flags; /* Flags defining array states for reshaping */
1784
1785	/*
1786	 * This offset tracks the progress of a raid
1787	 * set reshape in order to be able to restart it
1788	 */
1789	__le64 reshape_position;
1790
1791	/*
1792	 * These define the properties of the array in case of an interrupted reshape
1793	 */
1794	__le32 new_level;
1795	__le32 new_layout;
1796	__le32 new_stripe_sectors;
1797	__le32 delta_disks;
1798
1799	__le64 array_sectors; /* Array size in sectors */
1800
1801	/*
1802	 * Sector offsets to data on devices (reshaping).
1803	 * Needed to support out of place reshaping, thus
1804	 * not writing over any stripes whilst converting
1805	 * them from old to new layout
1806	 */
1807	__le64 data_offset;
1808	__le64 new_data_offset;
1809
1810	__le64 sectors; /* Used device size in sectors */
1811
1812	/*
1813	 * Additonal Bit field of devices indicating failures to support
1814	 * up to 256 devices with the 1.9.0 on-disk metadata format
1815	 */
1816	__le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
1817
1818	__le32 incompat_features;	/* Used to indicate any incompatible features */
1819
1820	/* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
1821} __packed;
1822
1823/*
1824 * Check for reshape constraints on raid set @rs:
1825 *
1826 * - reshape function non-existent
1827 * - degraded set
1828 * - ongoing recovery
1829 * - ongoing reshape
1830 *
1831 * Returns 0 if none or -EPERM if given constraint
1832 * and error message reference in @errmsg
1833 */
1834static int rs_check_reshape(struct raid_set *rs)
1835{
1836	struct mddev *mddev = &rs->md;
1837
1838	if (!mddev->pers || !mddev->pers->check_reshape)
1839		rs->ti->error = "Reshape not supported";
1840	else if (mddev->degraded)
1841		rs->ti->error = "Can't reshape degraded raid set";
1842	else if (rs_is_recovering(rs))
1843		rs->ti->error = "Convert request on recovering raid set prohibited";
1844	else if (rs_is_reshaping(rs))
1845		rs->ti->error = "raid set already reshaping!";
1846	else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
1847		rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
1848	else
1849		return 0;
1850
1851	return -EPERM;
1852}
1853
1854static int read_disk_sb(struct md_rdev *rdev, int size)
1855{
1856	BUG_ON(!rdev->sb_page);
1857
1858	if (rdev->sb_loaded)
1859		return 0;
1860
1861	if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, true)) {
 
 
1862		DMERR("Failed to read superblock of device at position %d",
1863		      rdev->raid_disk);
1864		md_error(rdev->mddev, rdev);
1865		return -EINVAL;
 
1866	}
1867
1868	rdev->sb_loaded = 1;
1869
1870	return 0;
1871}
1872
1873static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1874{
1875	failed_devices[0] = le64_to_cpu(sb->failed_devices);
1876	memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
1877
1878	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
1879		int i = ARRAY_SIZE(sb->extended_failed_devices);
1880
1881		while (i--)
1882			failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
1883	}
1884}
1885
1886static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1887{
1888	int i = ARRAY_SIZE(sb->extended_failed_devices);
1889
1890	sb->failed_devices = cpu_to_le64(failed_devices[0]);
1891	while (i--)
1892		sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
1893}
1894
1895/*
1896 * Synchronize the superblock members with the raid set properties
1897 *
1898 * All superblock data is little endian.
1899 */
1900static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
1901{
1902	bool update_failed_devices = false;
1903	unsigned int i;
1904	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
1905	struct dm_raid_superblock *sb;
1906	struct raid_set *rs = container_of(mddev, struct raid_set, md);
1907
1908	/* No metadata device, no superblock */
1909	if (!rdev->meta_bdev)
1910		return;
1911
1912	BUG_ON(!rdev->sb_page);
1913
1914	sb = page_address(rdev->sb_page);
1915
1916	sb_retrieve_failed_devices(sb, failed_devices);
1917
1918	for (i = 0; i < rs->raid_disks; i++)
1919		if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
1920			update_failed_devices = true;
1921			set_bit(i, (void *) failed_devices);
1922		}
1923
1924	if (update_failed_devices)
1925		sb_update_failed_devices(sb, failed_devices);
1926
1927	sb->magic = cpu_to_le32(DM_RAID_MAGIC);
1928	sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
1929
1930	sb->num_devices = cpu_to_le32(mddev->raid_disks);
1931	sb->array_position = cpu_to_le32(rdev->raid_disk);
1932
1933	sb->events = cpu_to_le64(mddev->events);
1934
1935	sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
1936	sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
1937
1938	sb->level = cpu_to_le32(mddev->level);
1939	sb->layout = cpu_to_le32(mddev->layout);
1940	sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
1941
 
 
 
 
 
1942	sb->new_level = cpu_to_le32(mddev->new_level);
1943	sb->new_layout = cpu_to_le32(mddev->new_layout);
1944	sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
1945
1946	sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1947
1948	smp_rmb(); /* Make sure we access most recent reshape position */
1949	sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1950	if (le64_to_cpu(sb->reshape_position) != MaxSector) {
1951		/* Flag ongoing reshape */
1952		sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
1953
1954		if (mddev->delta_disks < 0 || mddev->reshape_backwards)
1955			sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
1956	} else {
1957		/* Clear reshape flags */
1958		sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
1959	}
1960
1961	sb->array_sectors = cpu_to_le64(mddev->array_sectors);
1962	sb->data_offset = cpu_to_le64(rdev->data_offset);
1963	sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
1964	sb->sectors = cpu_to_le64(rdev->sectors);
1965	sb->incompat_features = cpu_to_le32(0);
1966
1967	/* Zero out the rest of the payload after the size of the superblock */
1968	memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
1969}
1970
1971/*
1972 * super_load
1973 *
1974 * This function creates a superblock if one is not found on the device
1975 * and will decide which superblock to use if there's a choice.
1976 *
1977 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
1978 */
1979static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
1980{
1981	int r;
1982	struct dm_raid_superblock *sb;
1983	struct dm_raid_superblock *refsb;
1984	uint64_t events_sb, events_refsb;
1985
1986	rdev->sb_start = 0;
1987	rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
1988	if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) {
1989		DMERR("superblock size of a logical block is no longer valid");
1990		return -EINVAL;
1991	}
1992
1993	r = read_disk_sb(rdev, rdev->sb_size);
1994	if (r)
1995		return r;
1996
1997	sb = page_address(rdev->sb_page);
1998
1999	/*
2000	 * Two cases that we want to write new superblocks and rebuild:
2001	 * 1) New device (no matching magic number)
2002	 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
2003	 */
2004	if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
2005	    (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
2006		super_sync(rdev->mddev, rdev);
2007
2008		set_bit(FirstUse, &rdev->flags);
2009		sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2010
2011		/* Force writing of superblocks to disk */
2012		set_bit(MD_SB_CHANGE_DEVS, &rdev->mddev->sb_flags);
2013
2014		/* Any superblock is better than none, choose that if given */
2015		return refdev ? 0 : 1;
2016	}
2017
2018	if (!refdev)
2019		return 1;
2020
2021	events_sb = le64_to_cpu(sb->events);
2022
2023	refsb = page_address(refdev->sb_page);
2024	events_refsb = le64_to_cpu(refsb->events);
2025
2026	return (events_sb > events_refsb) ? 1 : 0;
2027}
2028
2029static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
2030{
2031	int role;
2032	unsigned int d;
2033	struct mddev *mddev = &rs->md;
2034	uint64_t events_sb;
2035	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2036	struct dm_raid_superblock *sb;
2037	uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
2038	struct md_rdev *r;
2039	struct dm_raid_superblock *sb2;
2040
2041	sb = page_address(rdev->sb_page);
2042	events_sb = le64_to_cpu(sb->events);
2043
2044	/*
2045	 * Initialise to 1 if this is a new superblock.
2046	 */
2047	mddev->events = events_sb ? : 1;
2048
2049	mddev->reshape_position = MaxSector;
2050
2051	mddev->raid_disks = le32_to_cpu(sb->num_devices);
2052	mddev->level = le32_to_cpu(sb->level);
2053	mddev->layout = le32_to_cpu(sb->layout);
2054	mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
2055
2056	/*
2057	 * Reshaping is supported, e.g. reshape_position is valid
2058	 * in superblock and superblock content is authoritative.
2059	 */
2060	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2061		/* Superblock is authoritative wrt given raid set layout! */
2062		mddev->new_level = le32_to_cpu(sb->new_level);
2063		mddev->new_layout = le32_to_cpu(sb->new_layout);
2064		mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
2065		mddev->delta_disks = le32_to_cpu(sb->delta_disks);
2066		mddev->array_sectors = le64_to_cpu(sb->array_sectors);
2067
2068		/* raid was reshaping and got interrupted */
2069		if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2070			if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2071				DMERR("Reshape requested but raid set is still reshaping");
2072				return -EINVAL;
2073			}
2074
2075			if (mddev->delta_disks < 0 ||
2076			    (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2077				mddev->reshape_backwards = 1;
2078			else
2079				mddev->reshape_backwards = 0;
2080
2081			mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2082			rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
2083		}
2084
2085	} else {
2086		/*
2087		 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2088		 */
2089		struct raid_type *rt_cur = get_raid_type_by_ll(mddev->level, mddev->layout);
2090		struct raid_type *rt_new = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
2091
2092		if (rs_takeover_requested(rs)) {
2093			if (rt_cur && rt_new)
2094				DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",
2095				      rt_cur->name, rt_new->name);
2096			else
2097				DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");
2098			return -EINVAL;
2099		} else if (rs_reshape_requested(rs)) {
2100			DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");
2101			if (mddev->layout != mddev->new_layout) {
2102				if (rt_cur && rt_new)
2103					DMERR("	 current layout %s vs new layout %s",
2104					      rt_cur->name, rt_new->name);
2105				else
2106					DMERR("	 current layout 0x%X vs new layout 0x%X",
2107					      le32_to_cpu(sb->layout), mddev->new_layout);
2108			}
2109			if (mddev->chunk_sectors != mddev->new_chunk_sectors)
2110				DMERR("	 current stripe sectors %u vs new stripe sectors %u",
2111				      mddev->chunk_sectors, mddev->new_chunk_sectors);
2112			if (rs->delta_disks)
2113				DMERR("	 current %u disks vs new %u disks",
2114				      mddev->raid_disks, mddev->raid_disks + rs->delta_disks);
2115			if (rs_is_raid10(rs)) {
2116				DMERR("	 Old layout: %s w/ %u copies",
2117				      raid10_md_layout_to_format(mddev->layout),
2118				      raid10_md_layout_to_copies(mddev->layout));
2119				DMERR("	 New layout: %s w/ %u copies",
2120				      raid10_md_layout_to_format(mddev->new_layout),
2121				      raid10_md_layout_to_copies(mddev->new_layout));
2122			}
2123			return -EINVAL;
2124		}
2125
2126		DMINFO("Discovered old metadata format; upgrading to extended metadata format");
2127	}
2128
2129	if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2130		mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2131
2132	/*
2133	 * During load, we set FirstUse if a new superblock was written.
2134	 * There are two reasons we might not have a superblock:
2135	 * 1) The raid set is brand new - in which case, all of the
2136	 *    devices must have their In_sync bit set.	Also,
2137	 *    recovery_cp must be 0, unless forced.
2138	 * 2) This is a new device being added to an old raid set
2139	 *    and the new device needs to be rebuilt - in which
2140	 *    case the In_sync bit will /not/ be set and
2141	 *    recovery_cp must be MaxSector.
2142	 * 3) This is/are a new device(s) being added to an old
2143	 *    raid set during takeover to a higher raid level
2144	 *    to provide capacity for redundancy or during reshape
2145	 *    to add capacity to grow the raid set.
2146	 */
2147	d = 0;
2148	rdev_for_each(r, mddev) {
 
 
 
2149		if (test_bit(FirstUse, &r->flags))
2150			new_devs++;
2151
2152		if (!test_bit(In_sync, &r->flags)) {
2153			DMINFO("Device %d specified for rebuild; clearing superblock",
2154				r->raid_disk);
2155			rebuilds++;
2156
2157			if (test_bit(FirstUse, &r->flags))
2158				rebuild_and_new++;
2159		}
2160
2161		d++;
2162	}
2163
2164	if (new_devs == rs->raid_disks || !rebuilds) {
2165		/* Replace a broken device */
2166		if (new_devs == 1 && !rs->delta_disks)
2167			;
2168		if (new_devs == rs->raid_disks) {
2169			DMINFO("Superblocks created for new raid set");
2170			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2171		} else if (new_devs != rebuilds &&
2172			   new_devs != rs->delta_disks) {
2173			DMERR("New device injected into existing raid set without "
2174			      "'delta_disks' or 'rebuild' parameter specified");
2175			return -EINVAL;
2176		}
2177	} else if (new_devs && new_devs != rebuilds) {
2178		DMERR("%u 'rebuild' devices cannot be injected into"
2179		      " a raid set with %u other first-time devices",
2180		      rebuilds, new_devs);
2181		return -EINVAL;
2182	} else if (rebuilds) {
2183		if (rebuild_and_new && rebuilds != rebuild_and_new) {
2184			DMERR("new device%s provided without 'rebuild'",
2185			      new_devs > 1 ? "s" : "");
2186			return -EINVAL;
2187		} else if (rs_is_recovering(rs)) {
2188			DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2189			      (unsigned long long) mddev->recovery_cp);
2190			return -EINVAL;
2191		} else if (rs_is_reshaping(rs)) {
2192			DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2193			      (unsigned long long) mddev->reshape_position);
2194			return -EINVAL;
2195		}
2196	}
2197
2198	/*
2199	 * Now we set the Faulty bit for those devices that are
2200	 * recorded in the superblock as failed.
2201	 */
2202	sb_retrieve_failed_devices(sb, failed_devices);
2203	rdev_for_each(r, mddev) {
2204		if (!r->sb_page)
 
2205			continue;
2206		sb2 = page_address(r->sb_page);
2207		sb2->failed_devices = 0;
2208		memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2209
2210		/*
2211		 * Check for any device re-ordering.
2212		 */
2213		if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2214			role = le32_to_cpu(sb2->array_position);
2215			if (role < 0)
2216				continue;
2217
2218			if (role != r->raid_disk) {
2219				if (rs_is_raid10(rs) && __is_raid10_near(mddev->layout)) {
2220					if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2221					    rs->raid_disks % rs->raid10_copies) {
2222						rs->ti->error =
2223							"Cannot change raid10 near set to odd # of devices!";
2224						return -EINVAL;
2225					}
2226
2227					sb2->array_position = cpu_to_le32(r->raid_disk);
2228
2229				} else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2230					   !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2231					   !rt_is_raid1(rs->raid_type)) {
2232					rs->ti->error = "Cannot change device positions in raid set";
2233					return -EINVAL;
2234				}
2235
2236				DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2237			}
2238
2239			/*
2240			 * Partial recovery is performed on
2241			 * returning failed devices.
2242			 */
2243			if (test_bit(role, (void *) failed_devices))
2244				set_bit(Faulty, &r->flags);
2245		}
2246	}
2247
2248	return 0;
2249}
2250
2251static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2252{
2253	struct mddev *mddev = &rs->md;
2254	struct dm_raid_superblock *sb;
2255
2256	if (rs_is_raid0(rs) || !rdev->sb_page)
2257		return 0;
2258
2259	sb = page_address(rdev->sb_page);
2260
2261	/*
2262	 * If mddev->events is not set, we know we have not yet initialized
2263	 * the array.
2264	 */
2265	if (!mddev->events && super_init_validation(rs, rdev))
2266		return -EINVAL;
2267
2268	if (le32_to_cpu(sb->compat_features) &&
2269	    le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2270		rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2271		return -EINVAL;
2272	}
2273
2274	if (sb->incompat_features) {
2275		rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2276		return -EINVAL;
2277	}
2278
2279	/* Enable bitmap creation for RAID levels != 0 */
2280	mddev->bitmap_info.offset = rt_is_raid0(rs->raid_type) ? 0 : to_sector(4096);
2281	rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2282
2283	if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2284		/* Retrieve device size stored in superblock to be prepared for shrink */
2285		rdev->sectors = le64_to_cpu(sb->sectors);
 
 
 
 
 
 
2286		rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2287		if (rdev->recovery_offset == MaxSector)
2288			set_bit(In_sync, &rdev->flags);
2289		/*
2290		 * If no reshape in progress -> we're recovering single
2291		 * disk(s) and have to set the device(s) to out-of-sync
2292		 */
2293		else if (!rs_is_reshaping(rs))
2294			clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2295	}
2296
2297	/*
2298	 * If a device comes back, set it as not In_sync and no longer faulty.
2299	 */
2300	if (test_and_clear_bit(Faulty, &rdev->flags)) {
2301		rdev->recovery_offset = 0;
2302		clear_bit(In_sync, &rdev->flags);
2303		rdev->saved_raid_disk = rdev->raid_disk;
2304	}
2305
2306	/* Reshape support -> restore repective data offsets */
2307	rdev->data_offset = le64_to_cpu(sb->data_offset);
2308	rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2309
2310	return 0;
2311}
2312
2313/*
2314 * Analyse superblocks and select the freshest.
2315 */
2316static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2317{
2318	int r;
2319	struct raid_dev *dev;
2320	struct md_rdev *rdev, *tmp, *freshest;
2321	struct mddev *mddev = &rs->md;
2322
2323	freshest = NULL;
2324	rdev_for_each_safe(rdev, tmp, mddev) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2325		/*
2326		 * Skipping super_load due to CTR_FLAG_SYNC will cause
2327		 * the array to undergo initialization again as
2328		 * though it were new.	This is the intended effect
2329		 * of the "sync" directive.
2330		 *
2331		 * When reshaping capability is added, we must ensure
2332		 * that the "sync" directive is disallowed during the
2333		 * reshape.
2334		 */
2335		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2336			continue;
2337
2338		if (!rdev->meta_bdev)
2339			continue;
2340
2341		r = super_load(rdev, freshest);
2342
2343		switch (r) {
2344		case 1:
2345			freshest = rdev;
2346			break;
2347		case 0:
2348			break;
2349		default:
 
2350			/*
2351			 * We have to keep any raid0 data/metadata device pairs or
2352			 * the MD raid0 personality will fail to start the array.
2353			 */
2354			if (rs_is_raid0(rs))
2355				continue;
2356
2357			dev = container_of(rdev, struct raid_dev, rdev);
2358			if (dev->meta_dev)
2359				dm_put_device(ti, dev->meta_dev);
2360
2361			dev->meta_dev = NULL;
2362			rdev->meta_bdev = NULL;
2363
2364			if (rdev->sb_page)
2365				put_page(rdev->sb_page);
2366
2367			rdev->sb_page = NULL;
2368
2369			rdev->sb_loaded = 0;
2370
2371			/*
2372			 * We might be able to salvage the data device
2373			 * even though the meta device has failed.  For
2374			 * now, we behave as though '- -' had been
2375			 * set for this device in the table.
 
 
2376			 */
2377			if (dev->data_dev)
2378				dm_put_device(ti, dev->data_dev);
2379
2380			dev->data_dev = NULL;
2381			rdev->bdev = NULL;
2382
2383			list_del(&rdev->same_set);
2384		}
2385	}
2386
2387	if (!freshest)
2388		return 0;
2389
2390	if (validate_raid_redundancy(rs)) {
2391		rs->ti->error = "Insufficient redundancy to activate array";
2392		return -EINVAL;
2393	}
2394
2395	/*
2396	 * Validation of the freshest device provides the source of
2397	 * validation for the remaining devices.
2398	 */
2399	rs->ti->error = "Unable to assemble array: Invalid superblocks";
2400	if (super_validate(rs, freshest))
2401		return -EINVAL;
2402
 
 
 
 
 
2403	rdev_for_each(rdev, mddev)
2404		if ((rdev != freshest) && super_validate(rs, rdev))
 
 
2405			return -EINVAL;
2406	return 0;
2407}
2408
2409/*
2410 * Adjust data_offset and new_data_offset on all disk members of @rs
2411 * for out of place reshaping if requested by contructor
2412 *
2413 * We need free space at the beginning of each raid disk for forward
2414 * and at the end for backward reshapes which userspace has to provide
2415 * via remapping/reordering of space.
2416 */
2417static int rs_adjust_data_offsets(struct raid_set *rs)
2418{
2419	sector_t data_offset = 0, new_data_offset = 0;
2420	struct md_rdev *rdev;
2421
2422	/* Constructor did not request data offset change */
2423	if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2424		if (!rs_is_reshapable(rs))
2425			goto out;
2426
2427		return 0;
2428	}
2429
2430	/* HM FIXME: get InSync raid_dev? */
2431	rdev = &rs->dev[0].rdev;
2432
2433	if (rs->delta_disks < 0) {
2434		/*
2435		 * Removing disks (reshaping backwards):
2436		 *
2437		 * - before reshape: data is at offset 0 and free space
2438		 *		     is at end of each component LV
2439		 *
2440		 * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2441		 */
2442		data_offset = 0;
2443		new_data_offset = rs->data_offset;
2444
2445	} else if (rs->delta_disks > 0) {
2446		/*
2447		 * Adding disks (reshaping forwards):
2448		 *
2449		 * - before reshape: data is at offset rs->data_offset != 0 and
2450		 *		     free space is at begin of each component LV
2451		 *
2452		 * - after reshape: data is at offset 0 on each component LV
2453		 */
2454		data_offset = rs->data_offset;
2455		new_data_offset = 0;
2456
2457	} else {
2458		/*
2459		 * User space passes in 0 for data offset after having removed reshape space
2460		 *
2461		 * - or - (data offset != 0)
2462		 *
2463		 * Changing RAID layout or chunk size -> toggle offsets
2464		 *
2465		 * - before reshape: data is at offset rs->data_offset 0 and
2466		 *		     free space is at end of each component LV
2467		 *		     -or-
2468		 *                   data is at offset rs->data_offset != 0 and
2469		 *		     free space is at begin of each component LV
2470		 *
2471		 * - after reshape: data is at offset 0 if it was at offset != 0
2472		 *                  or at offset != 0 if it was at offset 0
2473		 *                  on each component LV
2474		 *
2475		 */
2476		data_offset = rs->data_offset ? rdev->data_offset : 0;
2477		new_data_offset = data_offset ? 0 : rs->data_offset;
2478		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2479	}
2480
2481	/*
2482	 * Make sure we got a minimum amount of free sectors per device
2483	 */
2484	if (rs->data_offset &&
2485	    to_sector(i_size_read(rdev->bdev->bd_inode)) - rdev->sectors < MIN_FREE_RESHAPE_SPACE) {
2486		rs->ti->error = data_offset ? "No space for forward reshape" :
2487					      "No space for backward reshape";
2488		return -ENOSPC;
2489	}
2490out:
2491	/* Adjust data offsets on all rdevs */
 
 
 
 
 
 
 
2492	rdev_for_each(rdev, &rs->md) {
2493		rdev->data_offset = data_offset;
2494		rdev->new_data_offset = new_data_offset;
 
 
2495	}
2496
2497	return 0;
2498}
2499
2500/* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2501static void __reorder_raid_disk_indexes(struct raid_set *rs)
2502{
2503	int i = 0;
2504	struct md_rdev *rdev;
2505
2506	rdev_for_each(rdev, &rs->md) {
2507		rdev->raid_disk = i++;
2508		rdev->saved_raid_disk = rdev->new_raid_disk = -1;
 
 
2509	}
2510}
2511
2512/*
2513 * Setup @rs for takeover by a different raid level
2514 */
2515static int rs_setup_takeover(struct raid_set *rs)
2516{
2517	struct mddev *mddev = &rs->md;
2518	struct md_rdev *rdev;
2519	unsigned int d = mddev->raid_disks = rs->raid_disks;
2520	sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2521
2522	if (rt_is_raid10(rs->raid_type)) {
2523		if (mddev->level == 0) {
2524			/* Userpace reordered disks -> adjust raid_disk indexes */
2525			__reorder_raid_disk_indexes(rs);
2526
2527			/* raid0 -> raid10_far layout */
2528			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2529								   rs->raid10_copies);
2530		} else if (mddev->level == 1)
2531			/* raid1 -> raid10_near layout */
2532			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2533								   rs->raid_disks);
2534		else
2535			return -EINVAL;
2536
2537	}
2538
2539	clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2540	mddev->recovery_cp = MaxSector;
2541
2542	while (d--) {
2543		rdev = &rs->dev[d].rdev;
2544
2545		if (test_bit(d, (void *) rs->rebuild_disks)) {
2546			clear_bit(In_sync, &rdev->flags);
2547			clear_bit(Faulty, &rdev->flags);
2548			mddev->recovery_cp = rdev->recovery_offset = 0;
2549			/* Bitmap has to be created when we do an "up" takeover */
2550			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2551		}
2552
2553		rdev->new_data_offset = new_data_offset;
2554	}
2555
2556	return 0;
2557}
2558
2559/* Prepare @rs for reshape */
2560static int rs_prepare_reshape(struct raid_set *rs)
2561{
2562	bool reshape;
2563	struct mddev *mddev = &rs->md;
2564
2565	if (rs_is_raid10(rs)) {
2566		if (rs->raid_disks != mddev->raid_disks &&
2567		    __is_raid10_near(mddev->layout) &&
2568		    rs->raid10_copies &&
2569		    rs->raid10_copies != __raid10_near_copies(mddev->layout)) {
2570			/*
2571			 * raid disk have to be multiple of data copies to allow this conversion,
2572			 *
2573			 * This is actually not a reshape it is a
2574			 * rebuild of any additional mirrors per group
2575			 */
2576			if (rs->raid_disks % rs->raid10_copies) {
2577				rs->ti->error = "Can't reshape raid10 mirror groups";
2578				return -EINVAL;
2579			}
2580
2581			/* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2582			__reorder_raid_disk_indexes(rs);
2583			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2584								   rs->raid10_copies);
2585			mddev->new_layout = mddev->layout;
2586			reshape = false;
2587		} else
2588			reshape = true;
2589
2590	} else if (rs_is_raid456(rs))
2591		reshape = true;
2592
2593	else if (rs_is_raid1(rs)) {
2594		if (rs->delta_disks) {
2595			/* Process raid1 via delta_disks */
2596			mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
2597			reshape = true;
2598		} else {
2599			/* Process raid1 without delta_disks */
2600			mddev->raid_disks = rs->raid_disks;
2601			reshape = false;
2602		}
2603	} else {
2604		rs->ti->error = "Called with bogus raid type";
2605		return -EINVAL;
2606	}
2607
2608	if (reshape) {
2609		set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2610		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2611	} else if (mddev->raid_disks < rs->raid_disks)
2612		/* Create new superblocks and bitmaps, if any new disks */
2613		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2614
2615	return 0;
2616}
2617
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2618/*
2619 *
2620 * - change raid layout
2621 * - change chunk size
2622 * - add disks
2623 * - remove disks
2624 */
2625static int rs_setup_reshape(struct raid_set *rs)
2626{
2627	int r = 0;
2628	unsigned int cur_raid_devs, d;
 
2629	struct mddev *mddev = &rs->md;
2630	struct md_rdev *rdev;
2631
2632	mddev->delta_disks = rs->delta_disks;
2633	cur_raid_devs = mddev->raid_disks;
2634
2635	/* Ignore impossible layout change whilst adding/removing disks */
2636	if (mddev->delta_disks &&
2637	    mddev->layout != mddev->new_layout) {
2638		DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2639		mddev->new_layout = mddev->layout;
2640	}
2641
2642	/*
2643	 * Adjust array size:
2644	 *
2645	 * - in case of adding disks, array size has
2646	 *   to grow after the disk adding reshape,
2647	 *   which'll hapen in the event handler;
2648	 *   reshape will happen forward, so space has to
2649	 *   be available at the beginning of each disk
2650	 *
2651	 * - in case of removing disks, array size
2652	 *   has to shrink before starting the reshape,
2653	 *   which'll happen here;
2654	 *   reshape will happen backward, so space has to
2655	 *   be available at the end of each disk
2656	 *
2657	 * - data_offset and new_data_offset are
2658	 *   adjusted for aforementioned out of place
2659	 *   reshaping based on userspace passing in
2660	 *   the "data_offset <sectors>" key/value
2661	 *   pair via the constructor
2662	 */
2663
2664	/* Add disk(s) */
2665	if (rs->delta_disks > 0) {
2666		/* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2667		for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2668			rdev = &rs->dev[d].rdev;
2669			clear_bit(In_sync, &rdev->flags);
2670
2671			/*
2672			 * save_raid_disk needs to be -1, or recovery_offset will be set to 0
2673			 * by md, which'll store that erroneously in the superblock on reshape
2674			 */
2675			rdev->saved_raid_disk = -1;
2676			rdev->raid_disk = d;
2677
2678			rdev->sectors = mddev->dev_sectors;
2679			rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
2680		}
2681
2682		mddev->reshape_backwards = 0; /* adding disks -> forward reshape */
2683
2684	/* Remove disk(s) */
2685	} else if (rs->delta_disks < 0) {
2686		r = rs_set_dev_and_array_sectors(rs, true);
2687		mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2688
2689	/* Change layout and/or chunk size */
2690	} else {
2691		/*
2692		 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2693		 *
2694		 * keeping number of disks and do layout change ->
2695		 *
2696		 * toggle reshape_backward depending on data_offset:
2697		 *
2698		 * - free space upfront -> reshape forward
2699		 *
2700		 * - free space at the end -> reshape backward
2701		 *
2702		 *
2703		 * This utilizes free reshape space avoiding the need
2704		 * for userspace to move (parts of) LV segments in
2705		 * case of layout/chunksize change  (for disk
2706		 * adding/removing reshape space has to be at
2707		 * the proper address (see above with delta_disks):
2708		 *
2709		 * add disk(s)   -> begin
2710		 * remove disk(s)-> end
2711		 */
2712		mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2713	}
2714
 
 
 
 
 
 
 
 
 
2715	return r;
2716}
2717
2718/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2719 * Enable/disable discard support on RAID set depending on
2720 * RAID level and discard properties of underlying RAID members.
2721 */
2722static void configure_discard_support(struct raid_set *rs)
2723{
2724	int i;
2725	bool raid456;
2726	struct dm_target *ti = rs->ti;
2727
2728	/* Assume discards not supported until after checks below. */
2729	ti->discards_supported = false;
2730
2731	/* RAID level 4,5,6 require discard_zeroes_data for data integrity! */
2732	raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6);
2733
2734	for (i = 0; i < rs->raid_disks; i++) {
2735		struct request_queue *q;
2736
2737		if (!rs->dev[i].rdev.bdev)
2738			continue;
2739
2740		q = bdev_get_queue(rs->dev[i].rdev.bdev);
2741		if (!q || !blk_queue_discard(q))
2742			return;
2743
2744		if (raid456) {
2745			if (!q->limits.discard_zeroes_data)
2746				return;
2747			if (!devices_handle_discard_safely) {
2748				DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2749				DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2750				return;
2751			}
2752		}
2753	}
2754
2755	/* All RAID members properly support discards */
2756	ti->discards_supported = true;
2757
2758	/*
2759	 * RAID1 and RAID10 personalities require bio splitting,
2760	 * RAID0/4/5/6 don't and process large discard bios properly.
2761	 */
2762	ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10);
2763	ti->num_discard_bios = 1;
2764}
2765
2766/*
2767 * Construct a RAID0/1/10/4/5/6 mapping:
2768 * Args:
2769 *	<raid_type> <#raid_params> <raid_params>{0,}	\
2770 *	<#raid_devs> [<meta_dev1> <dev1>]{1,}
2771 *
2772 * <raid_params> varies by <raid_type>.	 See 'parse_raid_params' for
2773 * details on possible <raid_params>.
2774 *
2775 * Userspace is free to initialize the metadata devices, hence the superblocks to
2776 * enforce recreation based on the passed in table parameters.
2777 *
2778 */
2779static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
2780{
2781	int r;
2782	bool resize;
2783	struct raid_type *rt;
2784	unsigned int num_raid_params, num_raid_devs;
2785	sector_t calculated_dev_sectors;
2786	struct raid_set *rs = NULL;
2787	const char *arg;
2788	struct rs_layout rs_layout;
2789	struct dm_arg_set as = { argc, argv }, as_nrd;
2790	struct dm_arg _args[] = {
2791		{ 0, as.argc, "Cannot understand number of raid parameters" },
2792		{ 1, 254, "Cannot understand number of raid devices parameters" }
2793	};
2794
2795	/* Must have <raid_type> */
2796	arg = dm_shift_arg(&as);
2797	if (!arg) {
2798		ti->error = "No arguments";
2799		return -EINVAL;
2800	}
2801
2802	rt = get_raid_type(arg);
2803	if (!rt) {
2804		ti->error = "Unrecognised raid_type";
2805		return -EINVAL;
2806	}
2807
2808	/* Must have <#raid_params> */
2809	if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
2810		return -EINVAL;
2811
2812	/* number of raid device tupples <meta_dev data_dev> */
2813	as_nrd = as;
2814	dm_consume_args(&as_nrd, num_raid_params);
2815	_args[1].max = (as_nrd.argc - 1) / 2;
2816	if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
2817		return -EINVAL;
2818
2819	if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
2820		ti->error = "Invalid number of supplied raid devices";
2821		return -EINVAL;
2822	}
2823
2824	rs = raid_set_alloc(ti, rt, num_raid_devs);
2825	if (IS_ERR(rs))
2826		return PTR_ERR(rs);
2827
2828	r = parse_raid_params(rs, &as, num_raid_params);
2829	if (r)
2830		goto bad;
2831
2832	r = parse_dev_params(rs, &as);
2833	if (r)
2834		goto bad;
2835
2836	rs->md.sync_super = super_sync;
2837
2838	/*
2839	 * Calculate ctr requested array and device sizes to allow
2840	 * for superblock analysis needing device sizes defined.
2841	 *
2842	 * Any existing superblock will overwrite the array and device sizes
2843	 */
2844	r = rs_set_dev_and_array_sectors(rs, false);
2845	if (r)
2846		goto bad;
2847
2848	calculated_dev_sectors = rs->dev[0].rdev.sectors;
 
 
2849
2850	/*
2851	 * Backup any new raid set level, layout, ...
2852	 * requested to be able to compare to superblock
2853	 * members for conversion decisions.
2854	 */
2855	rs_config_backup(rs, &rs_layout);
2856
2857	r = analyse_superblocks(ti, rs);
2858	if (r)
2859		goto bad;
2860
2861	resize = calculated_dev_sectors != rs->dev[0].rdev.sectors;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2862
2863	INIT_WORK(&rs->md.event_work, do_table_event);
2864	ti->private = rs;
2865	ti->num_flush_bios = 1;
 
2866
2867	/* Restore any requested new layout for conversion decision */
2868	rs_config_restore(rs, &rs_layout);
2869
2870	/*
2871	 * Now that we have any superblock metadata available,
2872	 * check for new, recovering, reshaping, to be taken over,
2873	 * to be reshaped or an existing, unchanged raid set to
2874	 * run in sequence.
2875	 */
2876	if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
2877		/* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
2878		if (rs_is_raid6(rs) &&
2879		    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
2880			ti->error = "'nosync' not allowed for new raid6 set";
2881			r = -EINVAL;
2882			goto bad;
2883		}
2884		rs_setup_recovery(rs, 0);
2885		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2886		rs_set_new(rs);
2887	} else if (rs_is_recovering(rs)) {
2888		/* A recovering raid set may be resized */
2889		; /* skip setup rs */
2890	} else if (rs_is_reshaping(rs)) {
2891		/* Have to reject size change request during reshape */
2892		if (resize) {
2893			ti->error = "Can't resize a reshaping raid set";
2894			r = -EPERM;
2895			goto bad;
2896		}
2897		/* skip setup rs */
2898	} else if (rs_takeover_requested(rs)) {
2899		if (rs_is_reshaping(rs)) {
2900			ti->error = "Can't takeover a reshaping raid set";
2901			r = -EPERM;
2902			goto bad;
2903		}
2904
 
 
 
 
 
 
 
2905		/*
2906		 * If a takeover is needed, userspace sets any additional
2907		 * devices to rebuild and we can check for a valid request here.
2908		 *
2909		 * If acceptible, set the level to the new requested
2910		 * one, prohibit requesting recovery, allow the raid
2911		 * set to run and store superblocks during resume.
2912		 */
2913		r = rs_check_takeover(rs);
2914		if (r)
2915			goto bad;
2916
2917		r = rs_setup_takeover(rs);
2918		if (r)
2919			goto bad;
2920
2921		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2922		/* Takeover ain't recovery, so disable recovery */
2923		rs_setup_recovery(rs, MaxSector);
2924		rs_set_new(rs);
2925	} else if (rs_reshape_requested(rs)) {
 
 
 
2926		/*
2927		  * We can only prepare for a reshape here, because the
2928		  * raid set needs to run to provide the repective reshape
2929		  * check functions via its MD personality instance.
2930		  *
2931		  * So do the reshape check after md_run() succeeded.
2932		  */
2933		r = rs_prepare_reshape(rs);
2934		if (r)
2935			return r;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2936
2937		/* Reshaping ain't recovery, so disable recovery */
2938		rs_setup_recovery(rs, MaxSector);
 
2939		rs_set_cur(rs);
2940	} else {
 
2941		/* May not set recovery when a device rebuild is requested */
2942		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
 
 
2943			rs_setup_recovery(rs, MaxSector);
2944			set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2945		} else
2946			rs_setup_recovery(rs, test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ?
2947					      0 : (resize ? calculated_dev_sectors : MaxSector));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2948		rs_set_cur(rs);
2949	}
2950
2951	/* If constructor requested it, change data and new_data offsets */
2952	r = rs_adjust_data_offsets(rs);
2953	if (r)
2954		goto bad;
2955
 
 
 
2956	/* Start raid set read-only and assumed clean to change in raid_resume() */
2957	rs->md.ro = 1;
2958	rs->md.in_sync = 1;
 
 
2959	set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
2960
2961	/* Has to be held on running the array */
2962	mddev_lock_nointr(&rs->md);
2963	r = md_run(&rs->md);
2964	rs->md.in_sync = 0; /* Assume already marked dirty */
2965
2966	if (r) {
2967		ti->error = "Failed to run raid array";
2968		mddev_unlock(&rs->md);
2969		goto bad;
2970	}
2971
2972	rs->callbacks.congested_fn = raid_is_congested;
2973	dm_table_add_target_callbacks(ti->table, &rs->callbacks);
 
 
 
2974
2975	mddev_suspend(&rs->md);
 
 
 
 
 
 
 
 
 
2976
2977	/* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
2978	if (rs_is_raid456(rs)) {
2979		r = rs_set_raid456_stripe_cache(rs);
2980		if (r)
2981			goto bad_stripe_cache;
2982	}
2983
2984	/* Now do an early reshape check */
2985	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
2986		r = rs_check_reshape(rs);
2987		if (r)
2988			goto bad_check_reshape;
2989
2990		/* Restore new, ctr requested layout to perform check */
2991		rs_config_restore(rs, &rs_layout);
2992
2993		if (rs->md.pers->start_reshape) {
2994			r = rs->md.pers->check_reshape(&rs->md);
2995			if (r) {
2996				ti->error = "Reshape check failed";
2997				goto bad_check_reshape;
2998			}
2999		}
3000	}
3001
3002	/* Disable/enable discard support on raid set. */
3003	configure_discard_support(rs);
3004
3005	mddev_unlock(&rs->md);
3006	return 0;
3007
3008bad_stripe_cache:
3009bad_check_reshape:
3010	md_stop(&rs->md);
 
3011bad:
3012	raid_set_free(rs);
3013
3014	return r;
3015}
3016
3017static void raid_dtr(struct dm_target *ti)
3018{
3019	struct raid_set *rs = ti->private;
3020
3021	list_del_init(&rs->callbacks.list);
3022	md_stop(&rs->md);
 
 
 
 
3023	raid_set_free(rs);
3024}
3025
3026static int raid_map(struct dm_target *ti, struct bio *bio)
3027{
3028	struct raid_set *rs = ti->private;
3029	struct mddev *mddev = &rs->md;
3030
3031	/*
3032	 * If we're reshaping to add disk(s)), ti->len and
3033	 * mddev->array_sectors will differ during the process
3034	 * (ti->len > mddev->array_sectors), so we have to requeue
3035	 * bios with addresses > mddev->array_sectors here or
3036	 * there will occur accesses past EOD of the component
3037	 * data images thus erroring the raid set.
3038	 */
3039	if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
3040		return DM_MAPIO_REQUEUE;
3041
3042	mddev->pers->make_request(mddev, bio);
3043
3044	return DM_MAPIO_SUBMITTED;
3045}
3046
3047/* Return string describing the current sync action of @mddev */
3048static const char *decipher_sync_action(struct mddev *mddev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3049{
3050	if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
3051		return "frozen";
3052
3053	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3054	    (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
3055		if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
3056			return "reshape";
 
 
3057
3058		if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
3059			if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
3060				return "resync";
3061			else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
3062				return "check";
3063			return "repair";
3064		}
3065
3066		if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
3067			return "recover";
 
 
 
3068	}
3069
3070	return "idle";
3071}
3072
3073/*
3074 * Return status string @rdev
3075 *
3076 * Status characters:
3077 *
3078 *  'D' = Dead/Failed device
3079 *  'a' = Alive but not in-sync
3080 *  'A' = Alive and in-sync
3081 */
3082static const char *__raid_dev_status(struct md_rdev *rdev, bool array_in_sync)
3083{
3084	if (test_bit(Faulty, &rdev->flags))
 
 
 
3085		return "D";
3086	else if (!array_in_sync || !test_bit(In_sync, &rdev->flags))
 
 
 
 
3087		return "a";
3088	else
3089		return "A";
3090}
3091
3092/* Helper to return resync/reshape progress for @rs and @array_in_sync */
3093static sector_t rs_get_progress(struct raid_set *rs,
3094				sector_t resync_max_sectors, bool *array_in_sync)
3095{
3096	sector_t r, recovery_cp, curr_resync_completed;
3097	struct mddev *mddev = &rs->md;
3098
3099	curr_resync_completed = mddev->curr_resync_completed ?: mddev->recovery_cp;
3100	recovery_cp = mddev->recovery_cp;
3101	*array_in_sync = false;
3102
3103	if (rs_is_raid0(rs)) {
3104		r = resync_max_sectors;
3105		*array_in_sync = true;
3106
3107	} else {
3108		r = mddev->reshape_position;
 
 
 
3109
3110		/* Reshape is relative to the array size */
3111		if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ||
3112		    r != MaxSector) {
3113			if (r == MaxSector) {
3114				*array_in_sync = true;
3115				r = resync_max_sectors;
3116			} else {
3117				/* Got to reverse on backward reshape */
3118				if (mddev->reshape_backwards)
3119					r = mddev->array_sectors - r;
3120
3121				/* Devide by # of data stripes */
3122				sector_div(r, mddev_data_stripes(rs));
3123			}
 
 
 
 
 
3124
3125		/* Sync is relative to the component device size */
3126		} else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3127			r = curr_resync_completed;
3128		else
3129			r = recovery_cp;
3130
3131		if (r == MaxSector) {
3132			/*
3133			 * Sync complete.
 
 
3134			 */
3135			*array_in_sync = true;
3136			r = resync_max_sectors;
3137		} else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
3138			/*
3139			 * If "check" or "repair" is occurring, the raid set has
3140			 * undergone an initial sync and the health characters
3141			 * should not be 'a' anymore.
3142			 */
3143			*array_in_sync = true;
3144		} else {
3145			struct md_rdev *rdev;
 
 
 
 
 
3146
 
3147			/*
3148			 * The raid set may be doing an initial sync, or it may
3149			 * be rebuilding individual components.	 If all the
3150			 * devices are In_sync, then it is the raid set that is
3151			 * being initialized.
3152			 */
 
 
 
3153			rdev_for_each(rdev, mddev)
3154				if (!test_bit(In_sync, &rdev->flags))
3155					*array_in_sync = true;
3156#if 0
3157			r = 0; /* HM FIXME: TESTME: https://bugzilla.redhat.com/show_bug.cgi?id=1210637 ? */
3158#endif
3159		}
3160	}
3161
3162	return r;
3163}
3164
3165/* Helper to return @dev name or "-" if !@dev */
3166static const char *__get_dev_name(struct dm_dev *dev)
3167{
3168	return dev ? dev->name : "-";
3169}
3170
3171static void raid_status(struct dm_target *ti, status_type_t type,
3172			unsigned int status_flags, char *result, unsigned int maxlen)
3173{
3174	struct raid_set *rs = ti->private;
3175	struct mddev *mddev = &rs->md;
3176	struct r5conf *conf = mddev->private;
3177	int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3178	bool array_in_sync;
3179	unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3180	unsigned int sz = 0;
3181	unsigned int rebuild_disks;
3182	unsigned int write_mostly_params = 0;
3183	sector_t progress, resync_max_sectors, resync_mismatches;
3184	const char *sync_action;
3185	struct raid_type *rt;
3186	struct md_rdev *rdev;
3187
3188	switch (type) {
3189	case STATUSTYPE_INFO:
3190		/* *Should* always succeed */
3191		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3192		if (!rt)
3193			return;
3194
3195		DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3196
3197		/* Access most recent mddev properties for status output */
3198		smp_rmb();
3199		/* Get sensible max sectors even if raid set not yet started */
3200		resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3201				      mddev->resync_max_sectors : mddev->dev_sectors;
3202		progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync);
 
 
3203		resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
3204				    atomic64_read(&mddev->resync_mismatches) : 0;
3205		sync_action = decipher_sync_action(&rs->md);
3206
3207		/* HM FIXME: do we want another state char for raid0? It shows 'D' or 'A' now */
3208		rdev_for_each(rdev, mddev)
3209			DMEMIT(__raid_dev_status(rdev, array_in_sync));
3210
3211		/*
3212		 * In-sync/Reshape ratio:
3213		 *  The in-sync ratio shows the progress of:
3214		 *   - Initializing the raid set
3215		 *   - Rebuilding a subset of devices of the raid set
3216		 *  The user can distinguish between the two by referring
3217		 *  to the status characters.
3218		 *
3219		 *  The reshape ratio shows the progress of
3220		 *  changing the raid layout or the number of
3221		 *  disks of a raid set
3222		 */
3223		DMEMIT(" %llu/%llu", (unsigned long long) progress,
3224				     (unsigned long long) resync_max_sectors);
3225
3226		/*
3227		 * v1.5.0+:
3228		 *
3229		 * Sync action:
3230		 *   See Documentation/device-mapper/dm-raid.txt for
3231		 *   information on each of these states.
3232		 */
3233		DMEMIT(" %s", sync_action);
3234
3235		/*
3236		 * v1.5.0+:
3237		 *
3238		 * resync_mismatches/mismatch_cnt
3239		 *   This field shows the number of discrepancies found when
3240		 *   performing a "check" of the raid set.
3241		 */
3242		DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3243
3244		/*
3245		 * v1.9.0+:
3246		 *
3247		 * data_offset (needed for out of space reshaping)
3248		 *   This field shows the data offset into the data
3249		 *   image LV where the first stripes data starts.
3250		 *
3251		 * We keep data_offset equal on all raid disks of the set,
3252		 * so retrieving it from the first raid disk is sufficient.
3253		 */
3254		DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
 
 
 
 
 
 
3255		break;
3256
3257	case STATUSTYPE_TABLE:
3258		/* Report the table line string you would use to construct this raid set */
3259
3260		/* Calculate raid parameter count */
3261		for (i = 0; i < rs->raid_disks; i++)
3262			if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3263				write_mostly_params += 2;
3264		rebuild_disks = memweight(rs->rebuild_disks, DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks));
3265		raid_param_cnt += rebuild_disks * 2 +
3266				  write_mostly_params +
 
 
 
 
 
3267				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3268				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
3269		/* Emit table line */
 
3270		DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3271		if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3272			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3273					 raid10_md_layout_to_format(mddev->layout));
3274		if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3275			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3276					 raid10_md_layout_to_copies(mddev->layout));
3277		if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3278			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3279		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3280			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
3281		if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3282			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3283					   (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3284		if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3285			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3286					   (unsigned long long) rs->data_offset);
3287		if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3288			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3289					  mddev->bitmap_info.daemon_sleep);
3290		if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3291			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3292					 max(rs->delta_disks, mddev->delta_disks));
3293		if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3294			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3295					 max_nr_stripes);
3296		if (rebuild_disks)
3297			for (i = 0; i < rs->raid_disks; i++)
3298				if (test_bit(rs->dev[i].rdev.raid_disk, (void *) rs->rebuild_disks))
3299					DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD),
3300							 rs->dev[i].rdev.raid_disk);
3301		if (write_mostly_params)
3302			for (i = 0; i < rs->raid_disks; i++)
3303				if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3304					DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3305					       rs->dev[i].rdev.raid_disk);
3306		if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3307			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3308					  mddev->bitmap_info.max_write_behind);
3309		if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3310			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3311					 mddev->sync_speed_max);
3312		if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3313			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3314					 mddev->sync_speed_min);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3315		DMEMIT(" %d", rs->raid_disks);
3316		for (i = 0; i < rs->raid_disks; i++)
3317			DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
3318					 __get_dev_name(rs->dev[i].data_dev));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3319	}
3320}
3321
3322static int raid_message(struct dm_target *ti, unsigned int argc, char **argv)
 
3323{
3324	struct raid_set *rs = ti->private;
3325	struct mddev *mddev = &rs->md;
3326
3327	if (!mddev->pers || !mddev->pers->sync_request)
3328		return -EINVAL;
3329
3330	if (!strcasecmp(argv[0], "frozen"))
3331		set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3332	else
3333		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3334
3335	if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
3336		if (mddev->sync_thread) {
3337			set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3338			md_reap_sync_thread(mddev);
3339		}
3340	} else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3341		   test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
3342		return -EBUSY;
3343	else if (!strcasecmp(argv[0], "resync"))
3344		; /* MD_RECOVERY_NEEDED set below */
3345	else if (!strcasecmp(argv[0], "recover"))
3346		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3347	else {
3348		if (!strcasecmp(argv[0], "check"))
3349			set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3350		else if (!!strcasecmp(argv[0], "repair"))
 
 
 
 
 
3351			return -EINVAL;
3352		set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3353		set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3354	}
3355	if (mddev->ro == 2) {
3356		/* A write to sync_action is enough to justify
3357		 * canceling read-auto mode
3358		 */
3359		mddev->ro = 0;
3360		if (!mddev->suspended && mddev->sync_thread)
3361			md_wakeup_thread(mddev->sync_thread);
3362	}
3363	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3364	if (!mddev->suspended && mddev->thread)
3365		md_wakeup_thread(mddev->thread);
3366
3367	return 0;
3368}
3369
3370static int raid_iterate_devices(struct dm_target *ti,
3371				iterate_devices_callout_fn fn, void *data)
3372{
3373	struct raid_set *rs = ti->private;
3374	unsigned int i;
3375	int r = 0;
3376
3377	for (i = 0; !r && i < rs->md.raid_disks; i++)
3378		if (rs->dev[i].data_dev)
3379			r = fn(ti,
3380				 rs->dev[i].data_dev,
3381				 0, /* No offset on data devs */
3382				 rs->md.dev_sectors,
3383				 data);
3384
3385	return r;
3386}
3387
3388static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3389{
3390	struct raid_set *rs = ti->private;
3391	unsigned int chunk_size = to_bytes(rs->md.chunk_sectors);
3392
3393	blk_limits_io_min(limits, chunk_size);
3394	blk_limits_io_opt(limits, chunk_size * mddev_data_stripes(rs));
3395}
3396
3397static void raid_presuspend(struct dm_target *ti)
3398{
3399	struct raid_set *rs = ti->private;
3400
3401	md_stop_writes(&rs->md);
3402}
3403
3404static void raid_postsuspend(struct dm_target *ti)
3405{
3406	struct raid_set *rs = ti->private;
3407
3408	if (!rs->md.suspended)
3409		mddev_suspend(&rs->md);
 
 
3410
3411	rs->md.ro = 1;
 
3412}
3413
3414static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3415{
3416	int i;
3417	uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];
3418	unsigned long flags;
3419	bool cleared = false;
3420	struct dm_raid_superblock *sb;
3421	struct mddev *mddev = &rs->md;
3422	struct md_rdev *r;
3423
3424	/* RAID personalities have to provide hot add/remove methods or we need to bail out. */
3425	if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)
3426		return;
3427
3428	memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));
3429
3430	for (i = 0; i < rs->md.raid_disks; i++) {
3431		r = &rs->dev[i].rdev;
3432		if (test_bit(Faulty, &r->flags) && r->sb_page &&
3433		    sync_page_io(r, 0, r->sb_size, r->sb_page,
3434				 REQ_OP_READ, 0, true)) {
 
 
 
3435			DMINFO("Faulty %s device #%d has readable super block."
3436			       "  Attempting to revive it.",
3437			       rs->raid_type->name, i);
3438
3439			/*
3440			 * Faulty bit may be set, but sometimes the array can
3441			 * be suspended before the personalities can respond
3442			 * by removing the device from the array (i.e. calling
3443			 * 'hot_remove_disk').	If they haven't yet removed
3444			 * the failed device, its 'raid_disk' number will be
3445			 * '>= 0' - meaning we must call this function
3446			 * ourselves.
3447			 */
3448			if ((r->raid_disk >= 0) &&
3449			    (mddev->pers->hot_remove_disk(mddev, r) != 0))
3450				/* Failed to revive this device, try next */
3451				continue;
 
 
 
 
 
 
3452
3453			r->raid_disk = i;
3454			r->saved_raid_disk = i;
3455			flags = r->flags;
3456			clear_bit(Faulty, &r->flags);
3457			clear_bit(WriteErrorSeen, &r->flags);
3458			clear_bit(In_sync, &r->flags);
3459			if (mddev->pers->hot_add_disk(mddev, r)) {
3460				r->raid_disk = -1;
3461				r->saved_raid_disk = -1;
3462				r->flags = flags;
3463			} else {
 
3464				r->recovery_offset = 0;
3465				set_bit(i, (void *) cleared_failed_devices);
3466				cleared = true;
3467			}
3468		}
3469	}
3470
3471	/* If any failed devices could be cleared, update all sbs failed_devices bits */
3472	if (cleared) {
3473		uint64_t failed_devices[DISKS_ARRAY_ELEMS];
3474
3475		rdev_for_each(r, &rs->md) {
 
 
 
3476			sb = page_address(r->sb_page);
3477			sb_retrieve_failed_devices(sb, failed_devices);
3478
3479			for (i = 0; i < DISKS_ARRAY_ELEMS; i++)
3480				failed_devices[i] &= ~cleared_failed_devices[i];
3481
3482			sb_update_failed_devices(sb, failed_devices);
3483		}
3484	}
3485}
3486
3487static int __load_dirty_region_bitmap(struct raid_set *rs)
3488{
3489	int r = 0;
3490
3491	/* Try loading the bitmap unless "raid0", which does not have one */
3492	if (!rs_is_raid0(rs) &&
3493	    !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
3494		r = bitmap_load(&rs->md);
3495		if (r)
3496			DMERR("Failed to load bitmap");
3497	}
3498
3499	return r;
3500}
3501
3502/* Enforce updating all superblocks */
3503static void rs_update_sbs(struct raid_set *rs)
3504{
3505	struct mddev *mddev = &rs->md;
3506	int ro = mddev->ro;
3507
3508	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
3509	mddev->ro = 0;
3510	md_update_sb(mddev, 1);
3511	mddev->ro = ro;
3512}
3513
3514/*
3515 * Reshape changes raid algorithm of @rs to new one within personality
3516 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3517 * disks from a raid set thus growing/shrinking it or resizes the set
3518 *
3519 * Call mddev_lock_nointr() before!
3520 */
3521static int rs_start_reshape(struct raid_set *rs)
3522{
3523	int r;
3524	struct mddev *mddev = &rs->md;
3525	struct md_personality *pers = mddev->pers;
3526
 
 
 
3527	r = rs_setup_reshape(rs);
3528	if (r)
3529		return r;
3530
3531	/* Need to be resumed to be able to start reshape, recovery is frozen until raid_resume() though */
3532	if (mddev->suspended)
3533		mddev_resume(mddev);
3534
3535	/*
3536	 * Check any reshape constraints enforced by the personalility
3537	 *
3538	 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3539	 */
3540	r = pers->check_reshape(mddev);
3541	if (r) {
3542		rs->ti->error = "pers->check_reshape() failed";
3543		return r;
3544	}
3545
3546	/*
3547	 * Personality may not provide start reshape method in which
3548	 * case check_reshape above has already covered everything
3549	 */
3550	if (pers->start_reshape) {
3551		r = pers->start_reshape(mddev);
3552		if (r) {
3553			rs->ti->error = "pers->start_reshape() failed";
3554			return r;
3555		}
3556	}
3557
3558	/* Suspend because a resume will happen in raid_resume() */
3559	if (!mddev->suspended)
3560		mddev_suspend(mddev);
3561
3562	/*
3563	 * Now reshape got set up, update superblocks to
3564	 * reflect the fact so that a table reload will
3565	 * access proper superblock content in the ctr.
3566	 */
3567	rs_update_sbs(rs);
3568
3569	return 0;
3570}
3571
3572static int raid_preresume(struct dm_target *ti)
3573{
3574	int r;
3575	struct raid_set *rs = ti->private;
3576	struct mddev *mddev = &rs->md;
3577
3578	/* This is a resume after a suspend of the set -> it's already started */
3579	if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
3580		return 0;
3581
3582	/*
3583	 * The superblocks need to be updated on disk if the
3584	 * array is new or new devices got added (thus zeroed
3585	 * out by userspace) or __load_dirty_region_bitmap
3586	 * will overwrite them in core with old data or fail.
3587	 */
3588	if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
3589		rs_update_sbs(rs);
3590
3591	/* Load the bitmap from disk unless raid0 */
3592	r = __load_dirty_region_bitmap(rs);
3593	if (r)
3594		return r;
3595
3596	/* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */
 
 
 
 
 
 
 
 
3597	if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
3598	    mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) {
3599		r = bitmap_resize(mddev->bitmap, mddev->dev_sectors,
3600				  to_bytes(rs->requested_bitmap_chunk_sectors), 0);
 
 
 
3601		if (r)
3602			DMERR("Failed to resize bitmap");
3603	}
3604
3605	/* Check for any resize/reshape on @rs and adjust/initiate */
3606	/* Be prepared for mddev_resume() in raid_resume() */
3607	set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3608	if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
3609		set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3610		mddev->resync_min = mddev->recovery_cp;
 
 
3611	}
3612
3613	rs_set_capacity(rs);
3614
3615	/* Check for any reshape request unless new raid set */
3616	if (test_and_clear_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3617		/* Initiate a reshape. */
 
3618		mddev_lock_nointr(mddev);
3619		r = rs_start_reshape(rs);
3620		mddev_unlock(mddev);
3621		if (r)
3622			DMWARN("Failed to check/start reshape, continuing without change");
3623		r = 0;
3624	}
3625
3626	return r;
3627}
3628
3629#define RESUME_STAY_FROZEN_FLAGS (CTR_FLAG_DELTA_DISKS | CTR_FLAG_DATA_OFFSET)
3630
3631static void raid_resume(struct dm_target *ti)
3632{
3633	struct raid_set *rs = ti->private;
3634	struct mddev *mddev = &rs->md;
3635
3636	if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
3637		/*
3638		 * A secondary resume while the device is active.
3639		 * Take this opportunity to check whether any failed
3640		 * devices are reachable again.
3641		 */
3642		attempt_restore_of_faulty_devices(rs);
3643	}
3644
3645	mddev->ro = 0;
3646	mddev->in_sync = 0;
 
 
3647
3648	/*
3649	 * Keep the RAID set frozen if reshape/rebuild flags are set.
3650	 * The RAID set is unfrozen once the next table load/resume,
3651	 * which clears the reshape/rebuild flags, occurs.
3652	 * This ensures that the constructor for the inactive table
3653	 * retrieves an up-to-date reshape_position.
3654	 */
3655	if (!(rs->ctr_flags & RESUME_STAY_FROZEN_FLAGS))
3656		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3657
3658	if (mddev->suspended)
3659		mddev_resume(mddev);
 
3660}
3661
3662static struct target_type raid_target = {
3663	.name = "raid",
3664	.version = {1, 9, 1},
3665	.module = THIS_MODULE,
3666	.ctr = raid_ctr,
3667	.dtr = raid_dtr,
3668	.map = raid_map,
3669	.status = raid_status,
3670	.message = raid_message,
3671	.iterate_devices = raid_iterate_devices,
3672	.io_hints = raid_io_hints,
3673	.presuspend = raid_presuspend,
3674	.postsuspend = raid_postsuspend,
3675	.preresume = raid_preresume,
3676	.resume = raid_resume,
3677};
3678
3679static int __init dm_raid_init(void)
3680{
3681	DMINFO("Loading target version %u.%u.%u",
3682	       raid_target.version[0],
3683	       raid_target.version[1],
3684	       raid_target.version[2]);
3685	return dm_register_target(&raid_target);
3686}
3687
3688static void __exit dm_raid_exit(void)
3689{
3690	dm_unregister_target(&raid_target);
3691}
3692
3693module_init(dm_raid_init);
3694module_exit(dm_raid_exit);
3695
3696module_param(devices_handle_discard_safely, bool, 0644);
3697MODULE_PARM_DESC(devices_handle_discard_safely,
3698		 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
3699
3700MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
3701MODULE_ALIAS("dm-raid0");
3702MODULE_ALIAS("dm-raid1");
3703MODULE_ALIAS("dm-raid10");
3704MODULE_ALIAS("dm-raid4");
3705MODULE_ALIAS("dm-raid5");
3706MODULE_ALIAS("dm-raid6");
3707MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
3708MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
3709MODULE_LICENSE("GPL");