brintos / linux-shallow public Read only

1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2010-2011 Neil Brown4 * 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 device25 */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 the44	 * actual data/parity.	The reason for this is to not confuse45	 * ti->len and give more flexibility in altering size and46	 * characteristics.47	 *48	 * While it is possible for this device to be associated49	 * with a different physical device than the data_dev, it50	 * 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_flags61 *62 * 1 = no flag value63 * 2 = flag with value64 */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 to111 * be used in checks of valid / invalid flags112 * 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 options169 *170 * "raid6" does not accept "nosync", because it is not guaranteed171 * that both parity and q-syndrome are being written properly with172 * any writes173 */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 field201 * (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 processing205 * the raid set all over again.206 */207#define RT_FLAG_RS_PRERESUMED		0208#define RT_FLAG_RS_RESUMED		1209#define RT_FLAG_RS_BITMAP_LOADED	2210#define RT_FLAG_UPDATE_SBS		3211#define RT_FLAG_RESHAPE_RS		4212#define RT_FLAG_RS_SUSPENDED		5213#define RT_FLAG_RS_IN_SYNC		6214#define RT_FLAG_RS_RESYNCING		7215#define RT_FLAG_RS_GROW			8216#define RT_FLAG_RS_FROZEN		9217 218/* Array elements of 64 bit needed for rebuild/failed disk bits */219#define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)220 221/*222 * raid set level, layout and chunk sectors backup/restore223 */224struct rs_layout {225	int new_level;226	int new_layout;227	int new_chunk_sectors;228};229 230struct raid_set {231	struct dm_target *ti;232 233	uint32_t stripe_cache_entries;234	unsigned long ctr_flags;235	unsigned long runtime_flags;236 237	uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];238 239	int raid_disks;240	int delta_disks;241	int data_offset;242	int raid10_copies;243	int requested_bitmap_chunk_sectors;244 245	struct mddev md;246	struct raid_type *raid_type;247 248	sector_t array_sectors;249	sector_t dev_sectors;250 251	/* Optional raid4/5/6 journal device */252	struct journal_dev {253		struct dm_dev *dev;254		struct md_rdev rdev;255		int mode;256	} journal_dev;257 258	struct raid_dev dev[] __counted_by(raid_disks);259};260 261static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)262{263	struct mddev *mddev = &rs->md;264 265	l->new_level = mddev->new_level;266	l->new_layout = mddev->new_layout;267	l->new_chunk_sectors = mddev->new_chunk_sectors;268}269 270static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)271{272	struct mddev *mddev = &rs->md;273 274	mddev->new_level = l->new_level;275	mddev->new_layout = l->new_layout;276	mddev->new_chunk_sectors = l->new_chunk_sectors;277}278 279/* raid10 algorithms (i.e. formats) */280#define	ALGORITHM_RAID10_DEFAULT	0281#define	ALGORITHM_RAID10_NEAR		1282#define	ALGORITHM_RAID10_OFFSET		2283#define	ALGORITHM_RAID10_FAR		3284 285/* Supported raid types and properties. */286static struct raid_type {287	const char *name;		/* RAID algorithm. */288	const char *descr;		/* Descriptor text for logging. */289	const unsigned int parity_devs;	/* # of parity devices. */290	const unsigned int minimal_devs;/* minimal # of devices in set. */291	const unsigned int level;	/* RAID level. */292	const unsigned int algorithm;	/* RAID algorithm. */293} raid_types[] = {294	{"raid0",	  "raid0 (striping)",			    0, 2, 0,  0 /* NONE */},295	{"raid1",	  "raid1 (mirroring)",			    0, 2, 1,  0 /* NONE */},296	{"raid10_far",	  "raid10 far (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_FAR},297	{"raid10_offset", "raid10 offset (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_OFFSET},298	{"raid10_near",	  "raid10 near (striped mirrors)",	    0, 2, 10, ALGORITHM_RAID10_NEAR},299	{"raid10",	  "raid10 (striped mirrors)",		    0, 2, 10, ALGORITHM_RAID10_DEFAULT},300	{"raid4",	  "raid4 (dedicated first parity disk)",    1, 2, 5,  ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */301	{"raid5_n",	  "raid5 (dedicated last parity disk)",	    1, 2, 5,  ALGORITHM_PARITY_N},302	{"raid5_ls",	  "raid5 (left symmetric)",		    1, 2, 5,  ALGORITHM_LEFT_SYMMETRIC},303	{"raid5_rs",	  "raid5 (right symmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_SYMMETRIC},304	{"raid5_la",	  "raid5 (left asymmetric)",		    1, 2, 5,  ALGORITHM_LEFT_ASYMMETRIC},305	{"raid5_ra",	  "raid5 (right asymmetric)",		    1, 2, 5,  ALGORITHM_RIGHT_ASYMMETRIC},306	{"raid6_zr",	  "raid6 (zero restart)",		    2, 4, 6,  ALGORITHM_ROTATING_ZERO_RESTART},307	{"raid6_nr",	  "raid6 (N restart)",			    2, 4, 6,  ALGORITHM_ROTATING_N_RESTART},308	{"raid6_nc",	  "raid6 (N continue)",			    2, 4, 6,  ALGORITHM_ROTATING_N_CONTINUE},309	{"raid6_n_6",	  "raid6 (dedicated parity/Q n/6)",	    2, 4, 6,  ALGORITHM_PARITY_N_6},310	{"raid6_ls_6",	  "raid6 (left symmetric dedicated Q 6)",   2, 4, 6,  ALGORITHM_LEFT_SYMMETRIC_6},311	{"raid6_rs_6",	  "raid6 (right symmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_RIGHT_SYMMETRIC_6},312	{"raid6_la_6",	  "raid6 (left asymmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_LEFT_ASYMMETRIC_6},313	{"raid6_ra_6",	  "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6,  ALGORITHM_RIGHT_ASYMMETRIC_6}314};315 316/* True, if @v is in inclusive range [@min, @max] */317static bool __within_range(long v, long min, long max)318{319	return v >= min && v <= max;320}321 322/* All table line arguments are defined here */323static struct arg_name_flag {324	const unsigned long flag;325	const char *name;326} __arg_name_flags[] = {327	{ CTR_FLAG_SYNC, "sync"},328	{ CTR_FLAG_NOSYNC, "nosync"},329	{ CTR_FLAG_REBUILD, "rebuild"},330	{ CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},331	{ CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},332	{ CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},333	{ CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},334	{ CTR_FLAG_WRITE_MOSTLY, "write_mostly"},335	{ CTR_FLAG_STRIPE_CACHE, "stripe_cache"},336	{ CTR_FLAG_REGION_SIZE, "region_size"},337	{ CTR_FLAG_RAID10_COPIES, "raid10_copies"},338	{ CTR_FLAG_RAID10_FORMAT, "raid10_format"},339	{ CTR_FLAG_DATA_OFFSET, "data_offset"},340	{ CTR_FLAG_DELTA_DISKS, "delta_disks"},341	{ CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},342	{ CTR_FLAG_JOURNAL_DEV, "journal_dev" },343	{ CTR_FLAG_JOURNAL_MODE, "journal_mode" },344};345 346/* Return argument name string for given @flag */347static const char *dm_raid_arg_name_by_flag(const uint32_t flag)348{349	if (hweight32(flag) == 1) {350		struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);351 352		while (anf-- > __arg_name_flags)353			if (flag & anf->flag)354				return anf->name;355 356	} else357		DMERR("%s called with more than one flag!", __func__);358 359	return NULL;360}361 362/* Define correlation of raid456 journal cache modes and dm-raid target line parameters */363static struct {364	const int mode;365	const char *param;366} _raid456_journal_mode[] = {367	{ R5C_JOURNAL_MODE_WRITE_THROUGH, "writethrough" },368	{ R5C_JOURNAL_MODE_WRITE_BACK,    "writeback" }369};370 371/* Return MD raid4/5/6 journal mode for dm @journal_mode one */372static int dm_raid_journal_mode_to_md(const char *mode)373{374	int m = ARRAY_SIZE(_raid456_journal_mode);375 376	while (m--)377		if (!strcasecmp(mode, _raid456_journal_mode[m].param))378			return _raid456_journal_mode[m].mode;379 380	return -EINVAL;381}382 383/* Return dm-raid raid4/5/6 journal mode string for @mode */384static const char *md_journal_mode_to_dm_raid(const int mode)385{386	int m = ARRAY_SIZE(_raid456_journal_mode);387 388	while (m--)389		if (mode == _raid456_journal_mode[m].mode)390			return _raid456_journal_mode[m].param;391 392	return "unknown";393}394 395/*396 * Bool helpers to test for various raid levels of a raid set.397 * It's level as reported by the superblock rather than398 * the requested raid_type passed to the constructor.399 */400/* Return true, if raid set in @rs is raid0 */401static bool rs_is_raid0(struct raid_set *rs)402{403	return !rs->md.level;404}405 406/* Return true, if raid set in @rs is raid1 */407static bool rs_is_raid1(struct raid_set *rs)408{409	return rs->md.level == 1;410}411 412/* Return true, if raid set in @rs is raid10 */413static bool rs_is_raid10(struct raid_set *rs)414{415	return rs->md.level == 10;416}417 418/* Return true, if raid set in @rs is level 6 */419static bool rs_is_raid6(struct raid_set *rs)420{421	return rs->md.level == 6;422}423 424/* Return true, if raid set in @rs is level 4, 5 or 6 */425static bool rs_is_raid456(struct raid_set *rs)426{427	return __within_range(rs->md.level, 4, 6);428}429 430/* Return true, if raid set in @rs is reshapable */431static bool __is_raid10_far(int layout);432static bool rs_is_reshapable(struct raid_set *rs)433{434	return rs_is_raid456(rs) ||435	       (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));436}437 438/* Return true, if raid set in @rs is recovering */439static bool rs_is_recovering(struct raid_set *rs)440{441	return rs->md.recovery_cp < rs->md.dev_sectors;442}443 444/* Return true, if raid set in @rs is reshaping */445static bool rs_is_reshaping(struct raid_set *rs)446{447	return rs->md.reshape_position != MaxSector;448}449 450/*451 * bool helpers to test for various raid levels of a raid type @rt452 */453 454/* Return true, if raid type in @rt is raid0 */455static bool rt_is_raid0(struct raid_type *rt)456{457	return !rt->level;458}459 460/* Return true, if raid type in @rt is raid1 */461static bool rt_is_raid1(struct raid_type *rt)462{463	return rt->level == 1;464}465 466/* Return true, if raid type in @rt is raid10 */467static bool rt_is_raid10(struct raid_type *rt)468{469	return rt->level == 10;470}471 472/* Return true, if raid type in @rt is raid4/5 */473static bool rt_is_raid45(struct raid_type *rt)474{475	return __within_range(rt->level, 4, 5);476}477 478/* Return true, if raid type in @rt is raid6 */479static bool rt_is_raid6(struct raid_type *rt)480{481	return rt->level == 6;482}483 484/* Return true, if raid type in @rt is raid4/5/6 */485static bool rt_is_raid456(struct raid_type *rt)486{487	return __within_range(rt->level, 4, 6);488}489/* END: raid level bools */490 491/* Return valid ctr flags for the raid level of @rs */492static unsigned long __valid_flags(struct raid_set *rs)493{494	if (rt_is_raid0(rs->raid_type))495		return RAID0_VALID_FLAGS;496	else if (rt_is_raid1(rs->raid_type))497		return RAID1_VALID_FLAGS;498	else if (rt_is_raid10(rs->raid_type))499		return RAID10_VALID_FLAGS;500	else if (rt_is_raid45(rs->raid_type))501		return RAID45_VALID_FLAGS;502	else if (rt_is_raid6(rs->raid_type))503		return RAID6_VALID_FLAGS;504 505	return 0;506}507 508/*509 * Check for valid flags set on @rs510 *511 * Has to be called after parsing of the ctr flags!512 */513static int rs_check_for_valid_flags(struct raid_set *rs)514{515	if (rs->ctr_flags & ~__valid_flags(rs)) {516		rs->ti->error = "Invalid flags combination";517		return -EINVAL;518	}519 520	return 0;521}522 523/* MD raid10 bit definitions and helpers */524#define RAID10_OFFSET			(1 << 16) /* stripes with data copies area adjacent on devices */525#define RAID10_BROCKEN_USE_FAR_SETS	(1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */526#define RAID10_USE_FAR_SETS		(1 << 18) /* Use sets instead of whole stripe rotation */527#define RAID10_FAR_COPIES_SHIFT		8	  /* raid10 # far copies shift (2nd byte of layout) */528 529/* Return md raid10 near copies for @layout */530static unsigned int __raid10_near_copies(int layout)531{532	return layout & 0xFF;533}534 535/* Return md raid10 far copies for @layout */536static unsigned int __raid10_far_copies(int layout)537{538	return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);539}540 541/* Return true if md raid10 offset for @layout */542static bool __is_raid10_offset(int layout)543{544	return !!(layout & RAID10_OFFSET);545}546 547/* Return true if md raid10 near for @layout */548static bool __is_raid10_near(int layout)549{550	return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;551}552 553/* Return true if md raid10 far for @layout */554static bool __is_raid10_far(int layout)555{556	return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;557}558 559/* Return md raid10 layout string for @layout */560static const char *raid10_md_layout_to_format(int layout)561{562	/*563	 * Bit 16 stands for "offset"564	 * (i.e. adjacent stripes hold copies)565	 *566	 * Refer to MD's raid10.c for details567	 */568	if (__is_raid10_offset(layout))569		return "offset";570 571	if (__raid10_near_copies(layout) > 1)572		return "near";573 574	if (__raid10_far_copies(layout) > 1)575		return "far";576 577	return "unknown";578}579 580/* Return md raid10 algorithm for @name */581static int raid10_name_to_format(const char *name)582{583	if (!strcasecmp(name, "near"))584		return ALGORITHM_RAID10_NEAR;585	else if (!strcasecmp(name, "offset"))586		return ALGORITHM_RAID10_OFFSET;587	else if (!strcasecmp(name, "far"))588		return ALGORITHM_RAID10_FAR;589 590	return -EINVAL;591}592 593/* Return md raid10 copies for @layout */594static unsigned int raid10_md_layout_to_copies(int layout)595{596	return max(__raid10_near_copies(layout), __raid10_far_copies(layout));597}598 599/* Return md raid10 format id for @format string */600static int raid10_format_to_md_layout(struct raid_set *rs,601				      unsigned int algorithm,602				      unsigned int copies)603{604	unsigned int n = 1, f = 1, r = 0;605 606	/*607	 * MD resilienece flaw:608	 *609	 * enabling use_far_sets for far/offset formats causes copies610	 * to be colocated on the same devs together with their origins!611	 *612	 * -> disable it for now in the definition above613	 */614	if (algorithm == ALGORITHM_RAID10_DEFAULT ||615	    algorithm == ALGORITHM_RAID10_NEAR)616		n = copies;617 618	else if (algorithm == ALGORITHM_RAID10_OFFSET) {619		f = copies;620		r = RAID10_OFFSET;621		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))622			r |= RAID10_USE_FAR_SETS;623 624	} else if (algorithm == ALGORITHM_RAID10_FAR) {625		f = copies;626		if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))627			r |= RAID10_USE_FAR_SETS;628 629	} else630		return -EINVAL;631 632	return r | (f << RAID10_FAR_COPIES_SHIFT) | n;633}634/* END: MD raid10 bit definitions and helpers */635 636/* Check for any of the raid10 algorithms */637static bool __got_raid10(struct raid_type *rtp, const int layout)638{639	if (rtp->level == 10) {640		switch (rtp->algorithm) {641		case ALGORITHM_RAID10_DEFAULT:642		case ALGORITHM_RAID10_NEAR:643			return __is_raid10_near(layout);644		case ALGORITHM_RAID10_OFFSET:645			return __is_raid10_offset(layout);646		case ALGORITHM_RAID10_FAR:647			return __is_raid10_far(layout);648		default:649			break;650		}651	}652 653	return false;654}655 656/* Return raid_type for @name */657static struct raid_type *get_raid_type(const char *name)658{659	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);660 661	while (rtp-- > raid_types)662		if (!strcasecmp(rtp->name, name))663			return rtp;664 665	return NULL;666}667 668/* Return raid_type for @name based derived from @level and @layout */669static struct raid_type *get_raid_type_by_ll(const int level, const int layout)670{671	struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);672 673	while (rtp-- > raid_types) {674		/* RAID10 special checks based on @layout flags/properties */675		if (rtp->level == level &&676		    (__got_raid10(rtp, layout) || rtp->algorithm == layout))677			return rtp;678	}679 680	return NULL;681}682 683/* Adjust rdev sectors */684static void rs_set_rdev_sectors(struct raid_set *rs)685{686	struct mddev *mddev = &rs->md;687	struct md_rdev *rdev;688 689	/*690	 * raid10 sets rdev->sector to the device size, which691	 * is unintended in case of out-of-place reshaping692	 */693	rdev_for_each(rdev, mddev)694		if (!test_bit(Journal, &rdev->flags))695			rdev->sectors = mddev->dev_sectors;696}697 698/*699 * Change bdev capacity of @rs in case of a disk add/remove reshape700 */701static void rs_set_capacity(struct raid_set *rs)702{703	struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));704 705	set_capacity_and_notify(gendisk, rs->md.array_sectors);706}707 708/*709 * Set the mddev properties in @rs to the current710 * ones retrieved from the freshest superblock711 */712static void rs_set_cur(struct raid_set *rs)713{714	struct mddev *mddev = &rs->md;715 716	mddev->new_level = mddev->level;717	mddev->new_layout = mddev->layout;718	mddev->new_chunk_sectors = mddev->chunk_sectors;719}720 721/*722 * Set the mddev properties in @rs to the new723 * ones requested by the ctr724 */725static void rs_set_new(struct raid_set *rs)726{727	struct mddev *mddev = &rs->md;728 729	mddev->level = mddev->new_level;730	mddev->layout = mddev->new_layout;731	mddev->chunk_sectors = mddev->new_chunk_sectors;732	mddev->raid_disks = rs->raid_disks;733	mddev->delta_disks = 0;734}735 736static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,737				       unsigned int raid_devs)738{739	unsigned int i;740	struct raid_set *rs;741 742	if (raid_devs <= raid_type->parity_devs) {743		ti->error = "Insufficient number of devices";744		return ERR_PTR(-EINVAL);745	}746 747	rs = kzalloc(struct_size(rs, dev, raid_devs), GFP_KERNEL);748	if (!rs) {749		ti->error = "Cannot allocate raid context";750		return ERR_PTR(-ENOMEM);751	}752 753	if (mddev_init(&rs->md)) {754		kfree(rs);755		ti->error = "Cannot initialize raid context";756		return ERR_PTR(-ENOMEM);757	}758 759	rs->raid_disks = raid_devs;760	rs->delta_disks = 0;761 762	rs->ti = ti;763	rs->raid_type = raid_type;764	rs->stripe_cache_entries = 256;765	rs->md.raid_disks = raid_devs;766	rs->md.level = raid_type->level;767	rs->md.new_level = rs->md.level;768	rs->md.layout = raid_type->algorithm;769	rs->md.new_layout = rs->md.layout;770	rs->md.delta_disks = 0;771	rs->md.recovery_cp = MaxSector;772 773	for (i = 0; i < raid_devs; i++)774		md_rdev_init(&rs->dev[i].rdev);775 776	/*777	 * Remaining items to be initialized by further RAID params:778	 *  rs->md.persistent779	 *  rs->md.external780	 *  rs->md.chunk_sectors781	 *  rs->md.new_chunk_sectors782	 *  rs->md.dev_sectors783	 */784 785	return rs;786}787 788/* Free all @rs allocations */789static void raid_set_free(struct raid_set *rs)790{791	int i;792 793	if (rs->journal_dev.dev) {794		md_rdev_clear(&rs->journal_dev.rdev);795		dm_put_device(rs->ti, rs->journal_dev.dev);796	}797 798	for (i = 0; i < rs->raid_disks; i++) {799		if (rs->dev[i].meta_dev)800			dm_put_device(rs->ti, rs->dev[i].meta_dev);801		md_rdev_clear(&rs->dev[i].rdev);802		if (rs->dev[i].data_dev)803			dm_put_device(rs->ti, rs->dev[i].data_dev);804	}805 806	mddev_destroy(&rs->md);807	kfree(rs);808}809 810/*811 * For every device we have two words812 *  <meta_dev>: meta device name or '-' if missing813 *  <data_dev>: data device name or '-' if missing814 *815 * The following are permitted:816 *    - -817 *    - <data_dev>818 *    <meta_dev> <data_dev>819 *820 * The following is not allowed:821 *    <meta_dev> -822 *823 * This code parses those words.  If there is a failure,824 * the caller must use raid_set_free() to unwind the operations.825 */826static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)827{828	int i;829	int rebuild = 0;830	int metadata_available = 0;831	int r = 0;832	const char *arg;833 834	/* Put off the number of raid devices argument to get to dev pairs */835	arg = dm_shift_arg(as);836	if (!arg)837		return -EINVAL;838 839	for (i = 0; i < rs->raid_disks; i++) {840		rs->dev[i].rdev.raid_disk = i;841 842		rs->dev[i].meta_dev = NULL;843		rs->dev[i].data_dev = NULL;844 845		/*846		 * There are no offsets initially.847		 * Out of place reshape will set them accordingly.848		 */849		rs->dev[i].rdev.data_offset = 0;850		rs->dev[i].rdev.new_data_offset = 0;851		rs->dev[i].rdev.mddev = &rs->md;852 853		arg = dm_shift_arg(as);854		if (!arg)855			return -EINVAL;856 857		if (strcmp(arg, "-")) {858			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),859					  &rs->dev[i].meta_dev);860			if (r) {861				rs->ti->error = "RAID metadata device lookup failure";862				return r;863			}864 865			rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);866			if (!rs->dev[i].rdev.sb_page) {867				rs->ti->error = "Failed to allocate superblock page";868				return -ENOMEM;869			}870		}871 872		arg = dm_shift_arg(as);873		if (!arg)874			return -EINVAL;875 876		if (!strcmp(arg, "-")) {877			if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&878			    (!rs->dev[i].rdev.recovery_offset)) {879				rs->ti->error = "Drive designated for rebuild not specified";880				return -EINVAL;881			}882 883			if (rs->dev[i].meta_dev) {884				rs->ti->error = "No data device supplied with metadata device";885				return -EINVAL;886			}887 888			continue;889		}890 891		r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),892				  &rs->dev[i].data_dev);893		if (r) {894			rs->ti->error = "RAID device lookup failure";895			return r;896		}897 898		if (rs->dev[i].meta_dev) {899			metadata_available = 1;900			rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;901		}902		rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;903		list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);904		if (!test_bit(In_sync, &rs->dev[i].rdev.flags))905			rebuild++;906	}907 908	if (rs->journal_dev.dev)909		list_add_tail(&rs->journal_dev.rdev.same_set, &rs->md.disks);910 911	if (metadata_available) {912		rs->md.external = 0;913		rs->md.persistent = 1;914		rs->md.major_version = 2;915	} else if (rebuild && !rs->md.recovery_cp) {916		/*917		 * Without metadata, we will not be able to tell if the array918		 * is in-sync or not - we must assume it is not.  Therefore,919		 * it is impossible to rebuild a drive.920		 *921		 * Even if there is metadata, the on-disk information may922		 * indicate that the array is not in-sync and it will then923		 * fail at that time.924		 *925		 * User could specify 'nosync' option if desperate.926		 */927		rs->ti->error = "Unable to rebuild drive while array is not in-sync";928		return -EINVAL;929	}930 931	return 0;932}933 934/*935 * validate_region_size936 * @rs937 * @region_size:  region size in sectors.  If 0, pick a size (4MiB default).938 *939 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').940 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.941 *942 * Returns: 0 on success, -EINVAL on failure.943 */944static int validate_region_size(struct raid_set *rs, unsigned long region_size)945{946	unsigned long min_region_size = rs->ti->len / (1 << 21);947 948	if (rs_is_raid0(rs))949		return 0;950 951	if (!region_size) {952		/*953		 * Choose a reasonable default.	 All figures in sectors.954		 */955		if (min_region_size > (1 << 13)) {956			/* If not a power of 2, make it the next power of 2 */957			region_size = roundup_pow_of_two(min_region_size);958			DMINFO("Choosing default region size of %lu sectors",959			       region_size);960		} else {961			DMINFO("Choosing default region size of 4MiB");962			region_size = 1 << 13; /* sectors */963		}964	} else {965		/*966		 * Validate user-supplied value.967		 */968		if (region_size > rs->ti->len) {969			rs->ti->error = "Supplied region size is too large";970			return -EINVAL;971		}972 973		if (region_size < min_region_size) {974			DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",975			      region_size, min_region_size);976			rs->ti->error = "Supplied region size is too small";977			return -EINVAL;978		}979 980		if (!is_power_of_2(region_size)) {981			rs->ti->error = "Region size is not a power of 2";982			return -EINVAL;983		}984 985		if (region_size < rs->md.chunk_sectors) {986			rs->ti->error = "Region size is smaller than the chunk size";987			return -EINVAL;988		}989	}990 991	/*992	 * Convert sectors to bytes.993	 */994	rs->md.bitmap_info.chunksize = to_bytes(region_size);995 996	return 0;997}998 999/*1000 * validate_raid_redundancy1001 * @rs1002 *1003 * Determine if there are enough devices in the array that haven't1004 * failed (or are being rebuilt) to form a usable array.1005 *1006 * Returns: 0 on success, -EINVAL on failure.1007 */1008static int validate_raid_redundancy(struct raid_set *rs)1009{1010	unsigned int i, rebuild_cnt = 0;1011	unsigned int rebuilds_per_group = 0, copies, raid_disks;1012	unsigned int group_size, last_group_start;1013 1014	for (i = 0; i < rs->raid_disks; i++)1015		if (!test_bit(FirstUse, &rs->dev[i].rdev.flags) &&1016		    ((!test_bit(In_sync, &rs->dev[i].rdev.flags) ||1017		      !rs->dev[i].rdev.sb_page)))1018			rebuild_cnt++;1019 1020	switch (rs->md.level) {1021	case 0:1022		break;1023	case 1:1024		if (rebuild_cnt >= rs->md.raid_disks)1025			goto too_many;1026		break;1027	case 4:1028	case 5:1029	case 6:1030		if (rebuild_cnt > rs->raid_type->parity_devs)1031			goto too_many;1032		break;1033	case 10:1034		copies = raid10_md_layout_to_copies(rs->md.new_layout);1035		if (copies < 2) {1036			DMERR("Bogus raid10 data copies < 2!");1037			return -EINVAL;1038		}1039 1040		if (rebuild_cnt < copies)1041			break;1042 1043		/*1044		 * It is possible to have a higher rebuild count for RAID10,1045		 * as long as the failed devices occur in different mirror1046		 * groups (i.e. different stripes).1047		 *1048		 * When checking "near" format, make sure no adjacent devices1049		 * have failed beyond what can be handled.  In addition to the1050		 * simple case where the number of devices is a multiple of the1051		 * number of copies, we must also handle cases where the number1052		 * of devices is not a multiple of the number of copies.1053		 * E.g.	   dev1 dev2 dev3 dev4 dev51054		 *	    A	 A    B	   B	C1055		 *	    C	 D    D	   E	E1056		 */1057		raid_disks = min(rs->raid_disks, rs->md.raid_disks);1058		if (__is_raid10_near(rs->md.new_layout)) {1059			for (i = 0; i < raid_disks; i++) {1060				if (!(i % copies))1061					rebuilds_per_group = 0;1062				if ((!rs->dev[i].rdev.sb_page ||1063				    !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&1064				    (++rebuilds_per_group >= copies))1065					goto too_many;1066			}1067			break;1068		}1069 1070		/*1071		 * When checking "far" and "offset" formats, we need to ensure1072		 * that the device that holds its copy is not also dead or1073		 * being rebuilt.  (Note that "far" and "offset" formats only1074		 * support two copies right now.  These formats also only ever1075		 * use the 'use_far_sets' variant.)1076		 *1077		 * This check is somewhat complicated by the need to account1078		 * for arrays that are not a multiple of (far) copies.	This1079		 * results in the need to treat the last (potentially larger)1080		 * set differently.1081		 */1082		group_size = (raid_disks / copies);1083		last_group_start = (raid_disks / group_size) - 1;1084		last_group_start *= group_size;1085		for (i = 0; i < raid_disks; i++) {1086			if (!(i % copies) && !(i > last_group_start))1087				rebuilds_per_group = 0;1088			if ((!rs->dev[i].rdev.sb_page ||1089			     !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&1090			    (++rebuilds_per_group >= copies))1091				goto too_many;1092		}1093		break;1094	default:1095		if (rebuild_cnt)1096			return -EINVAL;1097	}1098 1099	return 0;1100 1101too_many:1102	return -EINVAL;1103}1104 1105/*1106 * Possible arguments are...1107 *	<chunk_size> [optional_args]1108 *1109 * Argument definitions1110 *    <chunk_size>			The number of sectors per disk that1111 *					will form the "stripe"1112 *    [[no]sync]			Force or prevent recovery of the1113 *					entire array1114 *    [rebuild <idx>]			Rebuild the drive indicated by the index1115 *    [daemon_sleep <ms>]		Time between bitmap daemon work to1116 *					clear bits1117 *    [min_recovery_rate <kB/sec/disk>]	Throttle RAID initialization1118 *    [max_recovery_rate <kB/sec/disk>]	Throttle RAID initialization1119 *    [write_mostly <idx>]		Indicate a write mostly drive via index1120 *    [max_write_behind <sectors>]	See '-write-behind=' (man mdadm)1121 *    [stripe_cache <sectors>]		Stripe cache size for higher RAIDs1122 *    [region_size <sectors>]		Defines granularity of bitmap1123 *    [journal_dev <dev>]		raid4/5/6 journaling deviice1124 *					(i.e. write hole closing log)1125 *1126 * RAID10-only options:1127 *    [raid10_copies <# copies>]	Number of copies.  (Default: 2)1128 *    [raid10_format <near|far|offset>] Layout algorithm.  (Default: near)1129 */1130static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,1131			     unsigned int num_raid_params)1132{1133	int value, raid10_format = ALGORITHM_RAID10_DEFAULT;1134	unsigned int raid10_copies = 2;1135	unsigned int i, write_mostly = 0;1136	unsigned int region_size = 0;1137	sector_t max_io_len;1138	const char *arg, *key;1139	struct raid_dev *rd;1140	struct raid_type *rt = rs->raid_type;1141 1142	arg = dm_shift_arg(as);1143	num_raid_params--; /* Account for chunk_size argument */1144 1145	if (kstrtoint(arg, 10, &value) < 0) {1146		rs->ti->error = "Bad numerical argument given for chunk_size";1147		return -EINVAL;1148	}1149 1150	/*1151	 * First, parse the in-order required arguments1152	 * "chunk_size" is the only argument of this type.1153	 */1154	if (rt_is_raid1(rt)) {1155		if (value)1156			DMERR("Ignoring chunk size parameter for RAID 1");1157		value = 0;1158	} else if (!is_power_of_2(value)) {1159		rs->ti->error = "Chunk size must be a power of 2";1160		return -EINVAL;1161	} else if (value < 8) {1162		rs->ti->error = "Chunk size value is too small";1163		return -EINVAL;1164	}1165 1166	rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;1167 1168	/*1169	 * We set each individual device as In_sync with a completed1170	 * 'recovery_offset'.  If there has been a device failure or1171	 * replacement then one of the following cases applies:1172	 *1173	 *   1) User specifies 'rebuild'.1174	 *	- Device is reset when param is read.1175	 *   2) A new device is supplied.1176	 *	- No matching superblock found, resets device.1177	 *   3) Device failure was transient and returns on reload.1178	 *	- Failure noticed, resets device for bitmap replay.1179	 *   4) Device hadn't completed recovery after previous failure.1180	 *	- Superblock is read and overrides recovery_offset.1181	 *1182	 * What is found in the superblocks of the devices is always1183	 * authoritative, unless 'rebuild' or '[no]sync' was specified.1184	 */1185	for (i = 0; i < rs->raid_disks; i++) {1186		set_bit(In_sync, &rs->dev[i].rdev.flags);1187		rs->dev[i].rdev.recovery_offset = MaxSector;1188	}1189 1190	/*1191	 * Second, parse the unordered optional arguments1192	 */1193	for (i = 0; i < num_raid_params; i++) {1194		key = dm_shift_arg(as);1195		if (!key) {1196			rs->ti->error = "Not enough raid parameters given";1197			return -EINVAL;1198		}1199 1200		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {1201			if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {1202				rs->ti->error = "Only one 'nosync' argument allowed";1203				return -EINVAL;1204			}1205			continue;1206		}1207		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {1208			if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {1209				rs->ti->error = "Only one 'sync' argument allowed";1210				return -EINVAL;1211			}1212			continue;1213		}1214		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {1215			if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {1216				rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";1217				return -EINVAL;1218			}1219			continue;1220		}1221 1222		arg = dm_shift_arg(as);1223		i++; /* Account for the argument pairs */1224		if (!arg) {1225			rs->ti->error = "Wrong number of raid parameters given";1226			return -EINVAL;1227		}1228 1229		/*1230		 * Parameters that take a string value are checked here.1231		 */1232		/* "raid10_format {near|offset|far} */1233		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {1234			if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {1235				rs->ti->error = "Only one 'raid10_format' argument pair allowed";1236				return -EINVAL;1237			}1238			if (!rt_is_raid10(rt)) {1239				rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";1240				return -EINVAL;1241			}1242			raid10_format = raid10_name_to_format(arg);1243			if (raid10_format < 0) {1244				rs->ti->error = "Invalid 'raid10_format' value given";1245				return raid10_format;1246			}1247			continue;1248		}1249 1250		/* "journal_dev <dev>" */1251		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV))) {1252			int r;1253			struct md_rdev *jdev;1254 1255			if (test_and_set_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {1256				rs->ti->error = "Only one raid4/5/6 set journaling device allowed";1257				return -EINVAL;1258			}1259			if (!rt_is_raid456(rt)) {1260				rs->ti->error = "'journal_dev' is an invalid parameter for this RAID type";1261				return -EINVAL;1262			}1263			r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),1264					  &rs->journal_dev.dev);1265			if (r) {1266				rs->ti->error = "raid4/5/6 journal device lookup failure";1267				return r;1268			}1269			jdev = &rs->journal_dev.rdev;1270			md_rdev_init(jdev);1271			jdev->mddev = &rs->md;1272			jdev->bdev = rs->journal_dev.dev->bdev;1273			jdev->sectors = bdev_nr_sectors(jdev->bdev);1274			if (jdev->sectors < MIN_RAID456_JOURNAL_SPACE) {1275				rs->ti->error = "No space for raid4/5/6 journal";1276				return -ENOSPC;1277			}1278			rs->journal_dev.mode = R5C_JOURNAL_MODE_WRITE_THROUGH;1279			set_bit(Journal, &jdev->flags);1280			continue;1281		}1282 1283		/* "journal_mode <mode>" ("journal_dev" mandatory!) */1284		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE))) {1285			int r;1286 1287			if (!test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {1288				rs->ti->error = "raid4/5/6 'journal_mode' is invalid without 'journal_dev'";1289				return -EINVAL;1290			}1291			if (test_and_set_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {1292				rs->ti->error = "Only one raid4/5/6 'journal_mode' argument allowed";1293				return -EINVAL;1294			}1295			r = dm_raid_journal_mode_to_md(arg);1296			if (r < 0) {1297				rs->ti->error = "Invalid 'journal_mode' argument";1298				return r;1299			}1300			rs->journal_dev.mode = r;1301			continue;1302		}1303 1304		/*1305		 * Parameters with number values from here on.1306		 */1307		if (kstrtoint(arg, 10, &value) < 0) {1308			rs->ti->error = "Bad numerical argument given in raid params";1309			return -EINVAL;1310		}1311 1312		if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {1313			/*1314			 * "rebuild" is being passed in by userspace to provide1315			 * indexes of replaced devices and to set up additional1316			 * devices on raid level takeover.1317			 */1318			if (!__within_range(value, 0, rs->raid_disks - 1)) {1319				rs->ti->error = "Invalid rebuild index given";1320				return -EINVAL;1321			}1322 1323			if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {1324				rs->ti->error = "rebuild for this index already given";1325				return -EINVAL;1326			}1327 1328			rd = rs->dev + value;1329			clear_bit(In_sync, &rd->rdev.flags);1330			clear_bit(Faulty, &rd->rdev.flags);1331			rd->rdev.recovery_offset = 0;1332			set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);1333		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {1334			if (!rt_is_raid1(rt)) {1335				rs->ti->error = "write_mostly option is only valid for RAID1";1336				return -EINVAL;1337			}1338 1339			if (!__within_range(value, 0, rs->md.raid_disks - 1)) {1340				rs->ti->error = "Invalid write_mostly index given";1341				return -EINVAL;1342			}1343 1344			write_mostly++;1345			set_bit(WriteMostly, &rs->dev[value].rdev.flags);1346			set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);1347		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {1348			if (!rt_is_raid1(rt)) {1349				rs->ti->error = "max_write_behind option is only valid for RAID1";1350				return -EINVAL;1351			}1352 1353			if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {1354				rs->ti->error = "Only one max_write_behind argument pair allowed";1355				return -EINVAL;1356			}1357 1358			/*1359			 * In device-mapper, we specify things in sectors, but1360			 * MD records this value in kB1361			 */1362			if (value < 0 || value / 2 > COUNTER_MAX) {1363				rs->ti->error = "Max write-behind limit out of range";1364				return -EINVAL;1365			}1366 1367			rs->md.bitmap_info.max_write_behind = value / 2;1368		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {1369			if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {1370				rs->ti->error = "Only one daemon_sleep argument pair allowed";1371				return -EINVAL;1372			}1373			if (value < 0) {1374				rs->ti->error = "daemon sleep period out of range";1375				return -EINVAL;1376			}1377			rs->md.bitmap_info.daemon_sleep = value;1378		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {1379			/* Userspace passes new data_offset after having extended the data image LV */1380			if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {1381				rs->ti->error = "Only one data_offset argument pair allowed";1382				return -EINVAL;1383			}1384			/* Ensure sensible data offset */1385			if (value < 0 ||1386			    (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {1387				rs->ti->error = "Bogus data_offset value";1388				return -EINVAL;1389			}1390			rs->data_offset = value;1391		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {1392			/* Define the +/-# of disks to add to/remove from the given raid set */1393			if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {1394				rs->ti->error = "Only one delta_disks argument pair allowed";1395				return -EINVAL;1396			}1397			/* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */1398			if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {1399				rs->ti->error = "Too many delta_disk requested";1400				return -EINVAL;1401			}1402 1403			rs->delta_disks = value;1404		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {1405			if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {1406				rs->ti->error = "Only one stripe_cache argument pair allowed";1407				return -EINVAL;1408			}1409 1410			if (!rt_is_raid456(rt)) {1411				rs->ti->error = "Inappropriate argument: stripe_cache";1412				return -EINVAL;1413			}1414 1415			if (value < 0) {1416				rs->ti->error = "Bogus stripe cache entries value";1417				return -EINVAL;1418			}1419			rs->stripe_cache_entries = value;1420		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {1421			if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {1422				rs->ti->error = "Only one min_recovery_rate argument pair allowed";1423				return -EINVAL;1424			}1425 1426			if (value < 0) {1427				rs->ti->error = "min_recovery_rate out of range";1428				return -EINVAL;1429			}1430			rs->md.sync_speed_min = value;1431		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {1432			if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {1433				rs->ti->error = "Only one max_recovery_rate argument pair allowed";1434				return -EINVAL;1435			}1436 1437			if (value < 0) {1438				rs->ti->error = "max_recovery_rate out of range";1439				return -EINVAL;1440			}1441			rs->md.sync_speed_max = value;1442		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {1443			if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {1444				rs->ti->error = "Only one region_size argument pair allowed";1445				return -EINVAL;1446			}1447 1448			region_size = value;1449			rs->requested_bitmap_chunk_sectors = value;1450		} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {1451			if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {1452				rs->ti->error = "Only one raid10_copies argument pair allowed";1453				return -EINVAL;1454			}1455 1456			if (!__within_range(value, 2, rs->md.raid_disks)) {1457				rs->ti->error = "Bad value for 'raid10_copies'";1458				return -EINVAL;1459			}1460 1461			raid10_copies = value;1462		} else {1463			DMERR("Unable to parse RAID parameter: %s", key);1464			rs->ti->error = "Unable to parse RAID parameter";1465			return -EINVAL;1466		}1467	}1468 1469	if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&1470	    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {1471		rs->ti->error = "sync and nosync are mutually exclusive";1472		return -EINVAL;1473	}1474 1475	if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&1476	    (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||1477	     test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {1478		rs->ti->error = "sync/nosync and rebuild are mutually exclusive";1479		return -EINVAL;1480	}1481 1482	if (write_mostly >= rs->md.raid_disks) {1483		rs->ti->error = "Can't set all raid1 devices to write_mostly";1484		return -EINVAL;1485	}1486 1487	if (rs->md.sync_speed_max &&1488	    rs->md.sync_speed_min > rs->md.sync_speed_max) {1489		rs->ti->error = "Bogus recovery rates";1490		return -EINVAL;1491	}1492 1493	if (validate_region_size(rs, region_size))1494		return -EINVAL;1495 1496	if (rs->md.chunk_sectors)1497		max_io_len = rs->md.chunk_sectors;1498	else1499		max_io_len = region_size;1500 1501	if (dm_set_target_max_io_len(rs->ti, max_io_len))1502		return -EINVAL;1503 1504	if (rt_is_raid10(rt)) {1505		if (raid10_copies > rs->md.raid_disks) {1506			rs->ti->error = "Not enough devices to satisfy specification";1507			return -EINVAL;1508		}1509 1510		rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);1511		if (rs->md.new_layout < 0) {1512			rs->ti->error = "Error getting raid10 format";1513			return rs->md.new_layout;1514		}1515 1516		rt = get_raid_type_by_ll(10, rs->md.new_layout);1517		if (!rt) {1518			rs->ti->error = "Failed to recognize new raid10 layout";1519			return -EINVAL;1520		}1521 1522		if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||1523		     rt->algorithm == ALGORITHM_RAID10_NEAR) &&1524		    test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {1525			rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";1526			return -EINVAL;1527		}1528	}1529 1530	rs->raid10_copies = raid10_copies;1531 1532	/* Assume there are no metadata devices until the drives are parsed */1533	rs->md.persistent = 0;1534	rs->md.external = 1;1535 1536	/* Check, if any invalid ctr arguments have been passed in for the raid level */1537	return rs_check_for_valid_flags(rs);1538}1539 1540/* Set raid4/5/6 cache size */1541static int rs_set_raid456_stripe_cache(struct raid_set *rs)1542{1543	int r;1544	struct r5conf *conf;1545	struct mddev *mddev = &rs->md;1546	uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;1547	uint32_t nr_stripes = rs->stripe_cache_entries;1548 1549	if (!rt_is_raid456(rs->raid_type)) {1550		rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";1551		return -EINVAL;1552	}1553 1554	if (nr_stripes < min_stripes) {1555		DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",1556		       nr_stripes, min_stripes);1557		nr_stripes = min_stripes;1558	}1559 1560	conf = mddev->private;1561	if (!conf) {1562		rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";1563		return -EINVAL;1564	}1565 1566	/* Try setting number of stripes in raid456 stripe cache */1567	if (conf->min_nr_stripes != nr_stripes) {1568		r = raid5_set_cache_size(mddev, nr_stripes);1569		if (r) {1570			rs->ti->error = "Failed to set raid4/5/6 stripe cache size";1571			return r;1572		}1573 1574		DMINFO("%u stripe cache entries", nr_stripes);1575	}1576 1577	return 0;1578}1579 1580/* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */1581static unsigned int mddev_data_stripes(struct raid_set *rs)1582{1583	return rs->md.raid_disks - rs->raid_type->parity_devs;1584}1585 1586/* Return # of data stripes of @rs (i.e. as of ctr) */1587static unsigned int rs_data_stripes(struct raid_set *rs)1588{1589	return rs->raid_disks - rs->raid_type->parity_devs;1590}1591 1592/*1593 * Retrieve rdev->sectors from any valid raid device of @rs1594 * to allow userpace to pass in arbitray "- -" device tupples.1595 */1596static sector_t __rdev_sectors(struct raid_set *rs)1597{1598	int i;1599 1600	for (i = 0; i < rs->raid_disks; i++) {1601		struct md_rdev *rdev = &rs->dev[i].rdev;1602 1603		if (!test_bit(Journal, &rdev->flags) &&1604		    rdev->bdev && rdev->sectors)1605			return rdev->sectors;1606	}1607 1608	return 0;1609}1610 1611/* Check that calculated dev_sectors fits all component devices. */1612static int _check_data_dev_sectors(struct raid_set *rs)1613{1614	sector_t ds = ~0;1615	struct md_rdev *rdev;1616 1617	rdev_for_each(rdev, &rs->md)1618		if (!test_bit(Journal, &rdev->flags) && rdev->bdev) {1619			ds = min(ds, bdev_nr_sectors(rdev->bdev));1620			if (ds < rs->md.dev_sectors) {1621				rs->ti->error = "Component device(s) too small";1622				return -EINVAL;1623			}1624		}1625 1626	return 0;1627}1628 1629/* Get reshape sectors from data_offsets or raid set */1630static sector_t _get_reshape_sectors(struct raid_set *rs)1631{1632	struct md_rdev *rdev;1633	sector_t reshape_sectors = 0;1634 1635	rdev_for_each(rdev, &rs->md)1636		if (!test_bit(Journal, &rdev->flags)) {1637			reshape_sectors = (rdev->data_offset > rdev->new_data_offset) ?1638					rdev->data_offset - rdev->new_data_offset :1639					rdev->new_data_offset - rdev->data_offset;1640			break;1641		}1642 1643	return max(reshape_sectors, (sector_t) rs->data_offset);1644}1645 1646/* Calculate the sectors per device and per array used for @rs */1647static int rs_set_dev_and_array_sectors(struct raid_set *rs, sector_t sectors, bool use_mddev)1648{1649	int delta_disks;1650	unsigned int data_stripes;1651	sector_t array_sectors = sectors, dev_sectors = sectors;1652	struct mddev *mddev = &rs->md;1653 1654	if (use_mddev) {1655		delta_disks = mddev->delta_disks;1656		data_stripes = mddev_data_stripes(rs);1657	} else {1658		delta_disks = rs->delta_disks;1659		data_stripes = rs_data_stripes(rs);1660	}1661 1662	/* Special raid1 case w/o delta_disks support (yet) */1663	if (rt_is_raid1(rs->raid_type))1664		;1665	else if (rt_is_raid10(rs->raid_type)) {1666		if (rs->raid10_copies < 2 ||1667		    delta_disks < 0) {1668			rs->ti->error = "Bogus raid10 data copies or delta disks";1669			return -EINVAL;1670		}1671 1672		dev_sectors *= rs->raid10_copies;1673		if (sector_div(dev_sectors, data_stripes))1674			goto bad;1675 1676		array_sectors = (data_stripes + delta_disks) * (dev_sectors - _get_reshape_sectors(rs));1677		if (sector_div(array_sectors, rs->raid10_copies))1678			goto bad;1679 1680	} else if (sector_div(dev_sectors, data_stripes))1681		goto bad;1682 1683	else1684		/* Striped layouts */1685		array_sectors = (data_stripes + delta_disks) * (dev_sectors - _get_reshape_sectors(rs));1686 1687	mddev->array_sectors = array_sectors;1688	mddev->dev_sectors = dev_sectors;1689	rs_set_rdev_sectors(rs);1690 1691	return _check_data_dev_sectors(rs);1692bad:1693	rs->ti->error = "Target length not divisible by number of data devices";1694	return -EINVAL;1695}1696 1697/* Setup recovery on @rs */1698static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)1699{1700	/* raid0 does not recover */1701	if (rs_is_raid0(rs))1702		rs->md.recovery_cp = MaxSector;1703	/*1704	 * A raid6 set has to be recovered either1705	 * completely or for the grown part to1706	 * ensure proper parity and Q-Syndrome1707	 */1708	else if (rs_is_raid6(rs))1709		rs->md.recovery_cp = dev_sectors;1710	/*1711	 * Other raid set types may skip recovery1712	 * depending on the 'nosync' flag.1713	 */1714	else1715		rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)1716				     ? MaxSector : dev_sectors;1717}1718 1719static void do_table_event(struct work_struct *ws)1720{1721	struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);1722 1723	smp_rmb(); /* Make sure we access most actual mddev properties */1724 1725	/* Only grow size resulting from added stripe(s) after reshape ended. */1726	if (!rs_is_reshaping(rs) &&1727	    rs->array_sectors > rs->md.array_sectors &&1728	    !rs->md.delta_disks &&1729	    rs->md.raid_disks == rs->raid_disks) {1730		/* The raid10 personality doesn't provide proper device sizes -> correct. */1731		if (rs_is_raid10(rs))1732			rs_set_rdev_sectors(rs);1733 1734		rs->md.array_sectors = rs->array_sectors;1735		rs_set_capacity(rs);1736	}1737 1738	dm_table_event(rs->ti->table);1739}1740 1741/*1742 * Make sure a valid takover (level switch) is being requested on @rs1743 *1744 * Conversions of raid sets from one MD personality to another1745 * have to conform to restrictions which are enforced here.1746 */1747static int rs_check_takeover(struct raid_set *rs)1748{1749	struct mddev *mddev = &rs->md;1750	unsigned int near_copies;1751 1752	if (rs->md.degraded) {1753		rs->ti->error = "Can't takeover degraded raid set";1754		return -EPERM;1755	}1756 1757	if (rs_is_reshaping(rs)) {1758		rs->ti->error = "Can't takeover reshaping raid set";1759		return -EPERM;1760	}1761 1762	switch (mddev->level) {1763	case 0:1764		/* raid0 -> raid1/5 with one disk */1765		if ((mddev->new_level == 1 || mddev->new_level == 5) &&1766		    mddev->raid_disks == 1)1767			return 0;1768 1769		/* raid0 -> raid10 */1770		if (mddev->new_level == 10 &&1771		    !(rs->raid_disks % mddev->raid_disks))1772			return 0;1773 1774		/* raid0 with multiple disks -> raid4/5/6 */1775		if (__within_range(mddev->new_level, 4, 6) &&1776		    mddev->new_layout == ALGORITHM_PARITY_N &&1777		    mddev->raid_disks > 1)1778			return 0;1779 1780		break;1781 1782	case 10:1783		/* Can't takeover raid10_offset! */1784		if (__is_raid10_offset(mddev->layout))1785			break;1786 1787		near_copies = __raid10_near_copies(mddev->layout);1788 1789		/* raid10* -> raid0 */1790		if (mddev->new_level == 0) {1791			/* Can takeover raid10_near with raid disks divisable by data copies! */1792			if (near_copies > 1 &&1793			    !(mddev->raid_disks % near_copies)) {1794				mddev->raid_disks /= near_copies;1795				mddev->delta_disks = mddev->raid_disks;1796				return 0;1797			}1798 1799			/* Can takeover raid10_far */1800			if (near_copies == 1 &&1801			    __raid10_far_copies(mddev->layout) > 1)1802				return 0;1803 1804			break;1805		}1806 1807		/* raid10_{near,far} -> raid1 */1808		if (mddev->new_level == 1 &&1809		    max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)1810			return 0;1811 1812		/* raid10_{near,far} with 2 disks -> raid4/5 */1813		if (__within_range(mddev->new_level, 4, 5) &&1814		    mddev->raid_disks == 2)1815			return 0;1816		break;1817 1818	case 1:1819		/* raid1 with 2 disks -> raid4/5 */1820		if (__within_range(mddev->new_level, 4, 5) &&1821		    mddev->raid_disks == 2) {1822			mddev->degraded = 1;1823			return 0;1824		}1825 1826		/* raid1 -> raid0 */1827		if (mddev->new_level == 0 &&1828		    mddev->raid_disks == 1)1829			return 0;1830 1831		/* raid1 -> raid10 */1832		if (mddev->new_level == 10)1833			return 0;1834		break;1835 1836	case 4:1837		/* raid4 -> raid0 */1838		if (mddev->new_level == 0)1839			return 0;1840 1841		/* raid4 -> raid1/5 with 2 disks */1842		if ((mddev->new_level == 1 || mddev->new_level == 5) &&1843		    mddev->raid_disks == 2)1844			return 0;1845 1846		/* raid4 -> raid5/6 with parity N */1847		if (__within_range(mddev->new_level, 5, 6) &&1848		    mddev->layout == ALGORITHM_PARITY_N)1849			return 0;1850		break;1851 1852	case 5:1853		/* raid5 with parity N -> raid0 */1854		if (mddev->new_level == 0 &&1855		    mddev->layout == ALGORITHM_PARITY_N)1856			return 0;1857 1858		/* raid5 with parity N -> raid4 */1859		if (mddev->new_level == 4 &&1860		    mddev->layout == ALGORITHM_PARITY_N)1861			return 0;1862 1863		/* raid5 with 2 disks -> raid1/4/10 */1864		if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&1865		    mddev->raid_disks == 2)1866			return 0;1867 1868		/* raid5_* ->  raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */1869		if (mddev->new_level == 6 &&1870		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||1871		      __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))1872			return 0;1873		break;1874 1875	case 6:1876		/* raid6 with parity N -> raid0 */1877		if (mddev->new_level == 0 &&1878		    mddev->layout == ALGORITHM_PARITY_N)1879			return 0;1880 1881		/* raid6 with parity N -> raid4 */1882		if (mddev->new_level == 4 &&1883		    mddev->layout == ALGORITHM_PARITY_N)1884			return 0;1885 1886		/* raid6_*_n with Q-Syndrome N -> raid5_* */1887		if (mddev->new_level == 5 &&1888		    ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||1889		     __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))1890			return 0;1891		break;1892 1893	default:1894		break;1895	}1896 1897	rs->ti->error = "takeover not possible";1898	return -EINVAL;1899}1900 1901/* True if @rs requested to be taken over */1902static bool rs_takeover_requested(struct raid_set *rs)1903{1904	return rs->md.new_level != rs->md.level;1905}1906 1907/* True if layout is set to reshape. */1908static bool rs_is_layout_change(struct raid_set *rs, bool use_mddev)1909{1910	return (use_mddev ? rs->md.delta_disks : rs->delta_disks) ||1911	       rs->md.new_layout != rs->md.layout ||1912	       rs->md.new_chunk_sectors != rs->md.chunk_sectors;1913}1914 1915/* True if @rs is requested to reshape by ctr */1916static bool rs_reshape_requested(struct raid_set *rs)1917{1918	bool change;1919	struct mddev *mddev = &rs->md;1920 1921	if (rs_takeover_requested(rs))1922		return false;1923 1924	if (rs_is_raid0(rs))1925		return false;1926 1927	change = rs_is_layout_change(rs, false);1928 1929	/* Historical case to support raid1 reshape without delta disks */1930	if (rs_is_raid1(rs)) {1931		if (rs->delta_disks)1932			return !!rs->delta_disks;1933 1934		return !change &&1935		       mddev->raid_disks != rs->raid_disks;1936	}1937 1938	if (rs_is_raid10(rs))1939		return change &&1940		       !__is_raid10_far(mddev->new_layout) &&1941		       rs->delta_disks >= 0;1942 1943	return change;1944}1945 1946/*  Features */1947#define	FEATURE_FLAG_SUPPORTS_V190	0x1 /* Supports extended superblock */1948 1949/* State flags for sb->flags */1950#define	SB_FLAG_RESHAPE_ACTIVE		0x11951#define	SB_FLAG_RESHAPE_BACKWARDS	0x21952 1953/*1954 * This structure is never routinely used by userspace, unlike md superblocks.1955 * Devices with this superblock should only ever be accessed via device-mapper.1956 */1957#define DM_RAID_MAGIC 0x64526D441958struct dm_raid_superblock {1959	__le32 magic;		/* "DmRd" */1960	__le32 compat_features;	/* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */1961 1962	__le32 num_devices;	/* Number of devices in this raid set. (Max 64) */1963	__le32 array_position;	/* The position of this drive in the raid set */1964 1965	__le64 events;		/* Incremented by md when superblock updated */1966	__le64 failed_devices;	/* Pre 1.9.0 part of bit field of devices to */1967				/* indicate failures (see extension below) */1968 1969	/*1970	 * This offset tracks the progress of the repair or replacement of1971	 * an individual drive.1972	 */1973	__le64 disk_recovery_offset;1974 1975	/*1976	 * This offset tracks the progress of the initial raid set1977	 * synchronisation/parity calculation.1978	 */1979	__le64 array_resync_offset;1980 1981	/*1982	 * raid characteristics1983	 */1984	__le32 level;1985	__le32 layout;1986	__le32 stripe_sectors;1987 1988	/********************************************************************1989	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!1990	 *1991	 * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist1992	 */1993 1994	__le32 flags; /* Flags defining array states for reshaping */1995 1996	/*1997	 * This offset tracks the progress of a raid1998	 * set reshape in order to be able to restart it1999	 */2000	__le64 reshape_position;2001 2002	/*2003	 * These define the properties of the array in case of an interrupted reshape2004	 */2005	__le32 new_level;2006	__le32 new_layout;2007	__le32 new_stripe_sectors;2008	__le32 delta_disks;2009 2010	__le64 array_sectors; /* Array size in sectors */2011 2012	/*2013	 * Sector offsets to data on devices (reshaping).2014	 * Needed to support out of place reshaping, thus2015	 * not writing over any stripes whilst converting2016	 * them from old to new layout2017	 */2018	__le64 data_offset;2019	__le64 new_data_offset;2020 2021	__le64 sectors; /* Used device size in sectors */2022 2023	/*2024	 * Additional Bit field of devices indicating failures to support2025	 * up to 256 devices with the 1.9.0 on-disk metadata format2026	 */2027	__le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];2028 2029	__le32 incompat_features;	/* Used to indicate any incompatible features */2030 2031	/* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */2032} __packed;2033 2034/*2035 * Check for reshape constraints on raid set @rs:2036 *2037 * - reshape function non-existent2038 * - degraded set2039 * - ongoing recovery2040 * - ongoing reshape2041 *2042 * Returns 0 if none or -EPERM if given constraint2043 * and error message reference in @errmsg2044 */2045static int rs_check_reshape(struct raid_set *rs)2046{2047	struct mddev *mddev = &rs->md;2048 2049	if (!mddev->pers || !mddev->pers->check_reshape)2050		rs->ti->error = "Reshape not supported";2051	else if (mddev->degraded)2052		rs->ti->error = "Can't reshape degraded raid set";2053	else if (rs_is_recovering(rs))2054		rs->ti->error = "Convert request on recovering raid set prohibited";2055	else if (rs_is_reshaping(rs))2056		rs->ti->error = "raid set already reshaping!";2057	else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))2058		rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";2059	else2060		return 0;2061 2062	return -EPERM;2063}2064 2065static int read_disk_sb(struct md_rdev *rdev, int size, bool force_reload)2066{2067	BUG_ON(!rdev->sb_page);2068 2069	if (rdev->sb_loaded && !force_reload)2070		return 0;2071 2072	rdev->sb_loaded = 0;2073 2074	if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, true)) {2075		DMERR("Failed to read superblock of device at position %d",2076		      rdev->raid_disk);2077		md_error(rdev->mddev, rdev);2078		set_bit(Faulty, &rdev->flags);2079		return -EIO;2080	}2081 2082	rdev->sb_loaded = 1;2083 2084	return 0;2085}2086 2087static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)2088{2089	failed_devices[0] = le64_to_cpu(sb->failed_devices);2090	memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));2091 2092	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {2093		int i = ARRAY_SIZE(sb->extended_failed_devices);2094 2095		while (i--)2096			failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);2097	}2098}2099 2100static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)2101{2102	int i = ARRAY_SIZE(sb->extended_failed_devices);2103 2104	sb->failed_devices = cpu_to_le64(failed_devices[0]);2105	while (i--)2106		sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);2107}2108 2109/*2110 * Synchronize the superblock members with the raid set properties2111 *2112 * All superblock data is little endian.2113 */2114static void super_sync(struct mddev *mddev, struct md_rdev *rdev)2115{2116	bool update_failed_devices = false;2117	unsigned int i;2118	uint64_t failed_devices[DISKS_ARRAY_ELEMS];2119	struct dm_raid_superblock *sb;2120	struct raid_set *rs = container_of(mddev, struct raid_set, md);2121 2122	/* No metadata device, no superblock */2123	if (!rdev->meta_bdev)2124		return;2125 2126	BUG_ON(!rdev->sb_page);2127 2128	sb = page_address(rdev->sb_page);2129 2130	sb_retrieve_failed_devices(sb, failed_devices);2131 2132	for (i = 0; i < rs->raid_disks; i++)2133		if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {2134			update_failed_devices = true;2135			set_bit(i, (void *) failed_devices);2136		}2137 2138	if (update_failed_devices)2139		sb_update_failed_devices(sb, failed_devices);2140 2141	sb->magic = cpu_to_le32(DM_RAID_MAGIC);2142	sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);2143 2144	sb->num_devices = cpu_to_le32(mddev->raid_disks);2145	sb->array_position = cpu_to_le32(rdev->raid_disk);2146 2147	sb->events = cpu_to_le64(mddev->events);2148 2149	sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);2150	sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);2151 2152	sb->level = cpu_to_le32(mddev->level);2153	sb->layout = cpu_to_le32(mddev->layout);2154	sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);2155 2156	/********************************************************************2157	 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!2158	 *2159	 * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist2160	 */2161	sb->new_level = cpu_to_le32(mddev->new_level);2162	sb->new_layout = cpu_to_le32(mddev->new_layout);2163	sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);2164 2165	sb->delta_disks = cpu_to_le32(mddev->delta_disks);2166 2167	smp_rmb(); /* Make sure we access most recent reshape position */2168	sb->reshape_position = cpu_to_le64(mddev->reshape_position);2169	if (le64_to_cpu(sb->reshape_position) != MaxSector) {2170		/* Flag ongoing reshape */2171		sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);2172 2173		if (mddev->delta_disks < 0 || mddev->reshape_backwards)2174			sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);2175	} else {2176		/* Clear reshape flags */2177		sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));2178	}2179 2180	sb->array_sectors = cpu_to_le64(mddev->array_sectors);2181	sb->data_offset = cpu_to_le64(rdev->data_offset);2182	sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);2183	sb->sectors = cpu_to_le64(rdev->sectors);2184	sb->incompat_features = cpu_to_le32(0);2185 2186	/* Zero out the rest of the payload after the size of the superblock */2187	memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));2188}2189 2190/*2191 * super_load2192 *2193 * This function creates a superblock if one is not found on the device2194 * and will decide which superblock to use if there's a choice.2195 *2196 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise2197 */2198static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)2199{2200	int r;2201	struct dm_raid_superblock *sb;2202	struct dm_raid_superblock *refsb;2203	uint64_t events_sb, events_refsb;2204 2205	r = read_disk_sb(rdev, rdev->sb_size, false);2206	if (r)2207		return r;2208 2209	sb = page_address(rdev->sb_page);2210 2211	/*2212	 * Two cases that we want to write new superblocks and rebuild:2213	 * 1) New device (no matching magic number)2214	 * 2) Device specified for rebuild (!In_sync w/ offset == 0)2215	 */2216	if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||2217	    (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {2218		super_sync(rdev->mddev, rdev);2219 2220		set_bit(FirstUse, &rdev->flags);2221		sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);2222 2223		/* Force writing of superblocks to disk */2224		set_bit(MD_SB_CHANGE_DEVS, &rdev->mddev->sb_flags);2225 2226		/* Any superblock is better than none, choose that if given */2227		return refdev ? 0 : 1;2228	}2229 2230	if (!refdev)2231		return 1;2232 2233	events_sb = le64_to_cpu(sb->events);2234 2235	refsb = page_address(refdev->sb_page);2236	events_refsb = le64_to_cpu(refsb->events);2237 2238	return (events_sb > events_refsb) ? 1 : 0;2239}2240 2241static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)2242{2243	int role;2244	struct mddev *mddev = &rs->md;2245	uint64_t events_sb;2246	uint64_t failed_devices[DISKS_ARRAY_ELEMS];2247	struct dm_raid_superblock *sb;2248	uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;2249	struct md_rdev *r;2250	struct dm_raid_superblock *sb2;2251 2252	sb = page_address(rdev->sb_page);2253	events_sb = le64_to_cpu(sb->events);2254 2255	/*2256	 * Initialise to 1 if this is a new superblock.2257	 */2258	mddev->events = events_sb ? : 1;2259 2260	mddev->reshape_position = MaxSector;2261 2262	mddev->raid_disks = le32_to_cpu(sb->num_devices);2263	mddev->level = le32_to_cpu(sb->level);2264	mddev->layout = le32_to_cpu(sb->layout);2265	mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);2266 2267	/*2268	 * Reshaping is supported, e.g. reshape_position is valid2269	 * in superblock and superblock content is authoritative.2270	 */2271	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {2272		/* Superblock is authoritative wrt given raid set layout! */2273		mddev->new_level = le32_to_cpu(sb->new_level);2274		mddev->new_layout = le32_to_cpu(sb->new_layout);2275		mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);2276		mddev->delta_disks = le32_to_cpu(sb->delta_disks);2277		mddev->array_sectors = le64_to_cpu(sb->array_sectors);2278 2279		/* raid was reshaping and got interrupted */2280		if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {2281			if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {2282				DMERR("Reshape requested but raid set is still reshaping");2283				return -EINVAL;2284			}2285 2286			if (mddev->delta_disks < 0 ||2287			    (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))2288				mddev->reshape_backwards = 1;2289			else2290				mddev->reshape_backwards = 0;2291 2292			mddev->reshape_position = le64_to_cpu(sb->reshape_position);2293			rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);2294		}2295 2296	} else {2297		/*2298		 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata2299		 */2300		struct raid_type *rt_cur = get_raid_type_by_ll(mddev->level, mddev->layout);2301		struct raid_type *rt_new = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);2302 2303		if (rs_takeover_requested(rs)) {2304			if (rt_cur && rt_new)2305				DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",2306				      rt_cur->name, rt_new->name);2307			else2308				DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");2309			return -EINVAL;2310		} else if (rs_reshape_requested(rs)) {2311			DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");2312			if (mddev->layout != mddev->new_layout) {2313				if (rt_cur && rt_new)2314					DMERR("	 current layout %s vs new layout %s",2315					      rt_cur->name, rt_new->name);2316				else2317					DMERR("	 current layout 0x%X vs new layout 0x%X",2318					      le32_to_cpu(sb->layout), mddev->new_layout);2319			}2320			if (mddev->chunk_sectors != mddev->new_chunk_sectors)2321				DMERR("	 current stripe sectors %u vs new stripe sectors %u",2322				      mddev->chunk_sectors, mddev->new_chunk_sectors);2323			if (rs->delta_disks)2324				DMERR("	 current %u disks vs new %u disks",2325				      mddev->raid_disks, mddev->raid_disks + rs->delta_disks);2326			if (rs_is_raid10(rs)) {2327				DMERR("	 Old layout: %s w/ %u copies",2328				      raid10_md_layout_to_format(mddev->layout),2329				      raid10_md_layout_to_copies(mddev->layout));2330				DMERR("	 New layout: %s w/ %u copies",2331				      raid10_md_layout_to_format(mddev->new_layout),2332				      raid10_md_layout_to_copies(mddev->new_layout));2333			}2334			return -EINVAL;2335		}2336 2337		DMINFO("Discovered old metadata format; upgrading to extended metadata format");2338	}2339 2340	if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))2341		mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);2342 2343	/*2344	 * During load, we set FirstUse if a new superblock was written.2345	 * There are two reasons we might not have a superblock:2346	 * 1) The raid set is brand new - in which case, all of the2347	 *    devices must have their In_sync bit set.	Also,2348	 *    recovery_cp must be 0, unless forced.2349	 * 2) This is a new device being added to an old raid set2350	 *    and the new device needs to be rebuilt - in which2351	 *    case the In_sync bit will /not/ be set and2352	 *    recovery_cp must be MaxSector.2353	 * 3) This is/are a new device(s) being added to an old2354	 *    raid set during takeover to a higher raid level2355	 *    to provide capacity for redundancy or during reshape2356	 *    to add capacity to grow the raid set.2357	 */2358	rdev_for_each(r, mddev) {2359		if (test_bit(Journal, &rdev->flags))2360			continue;2361 2362		if (test_bit(FirstUse, &r->flags))2363			new_devs++;2364 2365		if (!test_bit(In_sync, &r->flags)) {2366			DMINFO("Device %d specified for rebuild; clearing superblock",2367				r->raid_disk);2368			rebuilds++;2369 2370			if (test_bit(FirstUse, &r->flags))2371				rebuild_and_new++;2372		}2373	}2374 2375	if (new_devs == rs->raid_disks || !rebuilds) {2376		/* Replace a broken device */2377		if (new_devs == rs->raid_disks) {2378			DMINFO("Superblocks created for new raid set");2379			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);2380		} else if (new_devs != rebuilds &&2381			   new_devs != rs->delta_disks) {2382			DMERR("New device injected into existing raid set without "2383			      "'delta_disks' or 'rebuild' parameter specified");2384			return -EINVAL;2385		}2386	} else if (new_devs && new_devs != rebuilds) {2387		DMERR("%u 'rebuild' devices cannot be injected into"2388		      " a raid set with %u other first-time devices",2389		      rebuilds, new_devs);2390		return -EINVAL;2391	} else if (rebuilds) {2392		if (rebuild_and_new && rebuilds != rebuild_and_new) {2393			DMERR("new device%s provided without 'rebuild'",2394			      new_devs > 1 ? "s" : "");2395			return -EINVAL;2396		} else if (!test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && rs_is_recovering(rs)) {2397			DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",2398			      (unsigned long long) mddev->recovery_cp);2399			return -EINVAL;2400		} else if (rs_is_reshaping(rs)) {2401			DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",2402			      (unsigned long long) mddev->reshape_position);2403			return -EINVAL;2404		}2405	}2406 2407	/*2408	 * Now we set the Faulty bit for those devices that are2409	 * recorded in the superblock as failed.2410	 */2411	sb_retrieve_failed_devices(sb, failed_devices);2412	rdev_for_each(r, mddev) {2413		if (test_bit(Journal, &rdev->flags) ||2414		    !r->sb_page)2415			continue;2416		sb2 = page_address(r->sb_page);2417		sb2->failed_devices = 0;2418		memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));2419 2420		/*2421		 * Check for any device re-ordering.2422		 */2423		if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {2424			role = le32_to_cpu(sb2->array_position);2425			if (role < 0)2426				continue;2427 2428			if (role != r->raid_disk) {2429				if (rs_is_raid10(rs) && __is_raid10_near(mddev->layout)) {2430					if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||2431					    rs->raid_disks % rs->raid10_copies) {2432						rs->ti->error =2433							"Cannot change raid10 near set to odd # of devices!";2434						return -EINVAL;2435					}2436 2437					sb2->array_position = cpu_to_le32(r->raid_disk);2438 2439				} else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&2440					   !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&2441					   !rt_is_raid1(rs->raid_type)) {2442					rs->ti->error = "Cannot change device positions in raid set";2443					return -EINVAL;2444				}2445 2446				DMINFO("raid device #%d now at position #%d", role, r->raid_disk);2447			}2448 2449			/*2450			 * Partial recovery is performed on2451			 * returning failed devices.2452			 */2453			if (test_bit(role, (void *) failed_devices))2454				set_bit(Faulty, &r->flags);2455		}2456	}2457 2458	return 0;2459}2460 2461static int super_validate(struct raid_set *rs, struct md_rdev *rdev)2462{2463	struct mddev *mddev = &rs->md;2464	struct dm_raid_superblock *sb;2465 2466	if (rs_is_raid0(rs) || !rdev->sb_page || rdev->raid_disk < 0)2467		return 0;2468 2469	sb = page_address(rdev->sb_page);2470 2471	/*2472	 * If mddev->events is not set, we know we have not yet initialized2473	 * the array.2474	 */2475	if (!mddev->events && super_init_validation(rs, rdev))2476		return -EINVAL;2477 2478	if (le32_to_cpu(sb->compat_features) &&2479	    le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {2480		rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";2481		return -EINVAL;2482	}2483 2484	if (sb->incompat_features) {2485		rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";2486		return -EINVAL;2487	}2488 2489	/* Enable bitmap creation on @rs unless no metadevs or raid0 or journaled raid4/5/6 set. */2490	mddev->bitmap_info.offset = (rt_is_raid0(rs->raid_type) || rs->journal_dev.dev) ? 0 : to_sector(4096);2491	mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;2492 2493	if (!test_and_clear_bit(FirstUse, &rdev->flags)) {2494		/*2495		 * Retrieve rdev size stored in superblock to be prepared for shrink.2496		 * Check extended superblock members are present otherwise the size2497		 * will not be set!2498		 */2499		if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190)2500			rdev->sectors = le64_to_cpu(sb->sectors);2501 2502		rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);2503		if (rdev->recovery_offset == MaxSector)2504			set_bit(In_sync, &rdev->flags);2505		/*2506		 * If no reshape in progress -> we're recovering single2507		 * disk(s) and have to set the device(s) to out-of-sync2508		 */2509		else if (!rs_is_reshaping(rs))2510			clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */2511	}2512 2513	/*2514	 * If a device comes back, set it as not In_sync and no longer faulty.2515	 */2516	if (test_and_clear_bit(Faulty, &rdev->flags)) {2517		rdev->recovery_offset = 0;2518		clear_bit(In_sync, &rdev->flags);2519		rdev->saved_raid_disk = rdev->raid_disk;2520	}2521 2522	/* Reshape support -> restore respective data offsets */2523	rdev->data_offset = le64_to_cpu(sb->data_offset);2524	rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);2525 2526	return 0;2527}2528 2529/*2530 * Analyse superblocks and select the freshest.2531 */2532static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)2533{2534	int r;2535	struct md_rdev *rdev, *freshest;2536	struct mddev *mddev = &rs->md;2537 2538	freshest = NULL;2539	rdev_for_each(rdev, mddev) {2540		if (test_bit(Journal, &rdev->flags))2541			continue;2542 2543		if (!rdev->meta_bdev)2544			continue;2545 2546		/* Set superblock offset/size for metadata device. */2547		rdev->sb_start = 0;2548		rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);2549		if (rdev->sb_size < sizeof(struct dm_raid_superblock) || rdev->sb_size > PAGE_SIZE) {2550			DMERR("superblock size of a logical block is no longer valid");2551			return -EINVAL;2552		}2553 2554		/*2555		 * Skipping super_load due to CTR_FLAG_SYNC will cause2556		 * the array to undergo initialization again as2557		 * though it were new.	This is the intended effect2558		 * of the "sync" directive.2559		 *2560		 * With reshaping capability added, we must ensure that2561		 * the "sync" directive is disallowed during the reshape.2562		 */2563		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))2564			continue;2565 2566		r = super_load(rdev, freshest);2567 2568		switch (r) {2569		case 1:2570			freshest = rdev;2571			break;2572		case 0:2573			break;2574		default:2575			/* This is a failure to read the superblock from the metadata device. */2576			/*2577			 * We have to keep any raid0 data/metadata device pairs or2578			 * the MD raid0 personality will fail to start the array.2579			 */2580			if (rs_is_raid0(rs))2581				continue;2582 2583			/*2584			 * We keep the dm_devs to be able to emit the device tuple2585			 * properly on the table line in raid_status() (rather than2586			 * mistakenly acting as if '- -' got passed into the constructor).2587			 *2588			 * The rdev has to stay on the same_set list to allow for2589			 * the attempt to restore faulty devices on second resume.2590			 */2591			rdev->raid_disk = rdev->saved_raid_disk = -1;2592			break;2593		}2594	}2595 2596	if (!freshest)2597		return 0;2598 2599	/*2600	 * Validation of the freshest device provides the source of2601	 * validation for the remaining devices.2602	 */2603	rs->ti->error = "Unable to assemble array: Invalid superblocks";2604	if (super_validate(rs, freshest))2605		return -EINVAL;2606 2607	if (validate_raid_redundancy(rs)) {2608		rs->ti->error = "Insufficient redundancy to activate array";2609		return -EINVAL;2610	}2611 2612	rdev_for_each(rdev, mddev)2613		if (!test_bit(Journal, &rdev->flags) &&2614		    rdev != freshest &&2615		    super_validate(rs, rdev))2616			return -EINVAL;2617	return 0;2618}2619 2620/*2621 * Adjust data_offset and new_data_offset on all disk members of @rs2622 * for out of place reshaping if requested by constructor2623 *2624 * We need free space at the beginning of each raid disk for forward2625 * and at the end for backward reshapes which userspace has to provide2626 * via remapping/reordering of space.2627 */2628static int rs_adjust_data_offsets(struct raid_set *rs)2629{2630	sector_t data_offset = 0, new_data_offset = 0;2631	struct md_rdev *rdev;2632 2633	/* Constructor did not request data offset change */2634	if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {2635		if (!rs_is_reshapable(rs))2636			goto out;2637 2638		return 0;2639	}2640 2641	/* HM FIXME: get In_Sync raid_dev? */2642	rdev = &rs->dev[0].rdev;2643 2644	if (rs->delta_disks < 0) {2645		/*2646		 * Removing disks (reshaping backwards):2647		 *2648		 * - before reshape: data is at offset 0 and free space2649		 *		     is at end of each component LV2650		 *2651		 * - after reshape: data is at offset rs->data_offset != 0 on each component LV2652		 */2653		data_offset = 0;2654		new_data_offset = rs->data_offset;2655 2656	} else if (rs->delta_disks > 0) {2657		/*2658		 * Adding disks (reshaping forwards):2659		 *2660		 * - before reshape: data is at offset rs->data_offset != 0 and2661		 *		     free space is at begin of each component LV2662		 *2663		 * - after reshape: data is at offset 0 on each component LV2664		 */2665		data_offset = rs->data_offset;2666		new_data_offset = 0;2667 2668	} else {2669		/*2670		 * User space passes in 0 for data offset after having removed reshape space2671		 *2672		 * - or - (data offset != 0)2673		 *2674		 * Changing RAID layout or chunk size -> toggle offsets2675		 *2676		 * - before reshape: data is at offset rs->data_offset 0 and2677		 *		     free space is at end of each component LV2678		 *		     -or-2679		 *                   data is at offset rs->data_offset != 0 and2680		 *		     free space is at begin of each component LV2681		 *2682		 * - after reshape: data is at offset 0 if it was at offset != 02683		 *                  or at offset != 0 if it was at offset 02684		 *                  on each component LV2685		 *2686		 */2687		data_offset = rs->data_offset ? rdev->data_offset : 0;2688		new_data_offset = data_offset ? 0 : rs->data_offset;2689		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);2690	}2691 2692	/*2693	 * Make sure we got a minimum amount of free sectors per device2694	 */2695	if (rs->data_offset &&2696	    bdev_nr_sectors(rdev->bdev) - rs->md.dev_sectors < MIN_FREE_RESHAPE_SPACE) {2697		rs->ti->error = data_offset ? "No space for forward reshape" :2698					      "No space for backward reshape";2699		return -ENOSPC;2700	}2701out:2702	/*2703	 * Raise recovery_cp in case data_offset != 0 to2704	 * avoid false recovery positives in the constructor.2705	 */2706	if (rs->md.recovery_cp < rs->md.dev_sectors)2707		rs->md.recovery_cp += rs->dev[0].rdev.data_offset;2708 2709	/* Adjust data offsets on all rdevs but on any raid4/5/6 journal device */2710	rdev_for_each(rdev, &rs->md) {2711		if (!test_bit(Journal, &rdev->flags)) {2712			rdev->data_offset = data_offset;2713			rdev->new_data_offset = new_data_offset;2714		}2715	}2716 2717	return 0;2718}2719 2720/* Userpace reordered disks -> adjust raid_disk indexes in @rs */2721static void __reorder_raid_disk_indexes(struct raid_set *rs)2722{2723	int i = 0;2724	struct md_rdev *rdev;2725 2726	rdev_for_each(rdev, &rs->md) {2727		if (!test_bit(Journal, &rdev->flags)) {2728			rdev->raid_disk = i++;2729			rdev->saved_raid_disk = rdev->new_raid_disk = -1;2730		}2731	}2732}2733 2734/*2735 * Setup @rs for takeover by a different raid level2736 */2737static int rs_setup_takeover(struct raid_set *rs)2738{2739	struct mddev *mddev = &rs->md;2740	struct md_rdev *rdev;2741	unsigned int d = mddev->raid_disks = rs->raid_disks;2742	sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;2743 2744	if (rt_is_raid10(rs->raid_type)) {2745		if (rs_is_raid0(rs)) {2746			/* Userpace reordered disks -> adjust raid_disk indexes */2747			__reorder_raid_disk_indexes(rs);2748 2749			/* raid0 -> raid10_far layout */2750			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,2751								   rs->raid10_copies);2752		} else if (rs_is_raid1(rs))2753			/* raid1 -> raid10_near layout */2754			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,2755								   rs->raid_disks);2756		else2757			return -EINVAL;2758 2759	}2760 2761	clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);2762	mddev->recovery_cp = MaxSector;2763 2764	while (d--) {2765		rdev = &rs->dev[d].rdev;2766 2767		if (test_bit(d, (void *) rs->rebuild_disks)) {2768			clear_bit(In_sync, &rdev->flags);2769			clear_bit(Faulty, &rdev->flags);2770			mddev->recovery_cp = rdev->recovery_offset = 0;2771			/* Bitmap has to be created when we do an "up" takeover */2772			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);2773		}2774 2775		rdev->new_data_offset = new_data_offset;2776	}2777 2778	return 0;2779}2780 2781/* Prepare @rs for reshape */2782static int rs_prepare_reshape(struct raid_set *rs)2783{2784	bool reshape;2785	struct mddev *mddev = &rs->md;2786 2787	if (rs_is_raid10(rs)) {2788		if (rs->raid_disks != mddev->raid_disks &&2789		    __is_raid10_near(mddev->layout) &&2790		    rs->raid10_copies &&2791		    rs->raid10_copies != __raid10_near_copies(mddev->layout)) {2792			/*2793			 * raid disk have to be multiple of data copies to allow this conversion,2794			 *2795			 * This is actually not a reshape it is a2796			 * rebuild of any additional mirrors per group2797			 */2798			if (rs->raid_disks % rs->raid10_copies) {2799				rs->ti->error = "Can't reshape raid10 mirror groups";2800				return -EINVAL;2801			}2802 2803			/* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */2804			__reorder_raid_disk_indexes(rs);2805			mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,2806								   rs->raid10_copies);2807			mddev->new_layout = mddev->layout;2808			reshape = false;2809		} else2810			reshape = true;2811 2812	} else if (rs_is_raid456(rs))2813		reshape = true;2814 2815	else if (rs_is_raid1(rs)) {2816		if (rs->delta_disks) {2817			/* Process raid1 via delta_disks */2818			mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;2819			reshape = true;2820		} else {2821			/* Process raid1 without delta_disks */2822			mddev->raid_disks = rs->raid_disks;2823			reshape = false;2824		}2825	} else {2826		rs->ti->error = "Called with bogus raid type";2827		return -EINVAL;2828	}2829 2830	if (reshape) {2831		set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);2832		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);2833	} else if (mddev->raid_disks < rs->raid_disks)2834		/* Create new superblocks and bitmaps, if any new disks */2835		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);2836 2837	return 0;2838}2839 2840/*2841 * Reshape:2842 * - change raid layout2843 * - change chunk size2844 * - add disks2845 * - remove disks2846 */2847static int rs_setup_reshape(struct raid_set *rs)2848{2849	int r = 0;2850	unsigned int cur_raid_devs, d;2851	sector_t reshape_sectors = _get_reshape_sectors(rs);2852	struct mddev *mddev = &rs->md;2853	struct md_rdev *rdev;2854 2855	mddev->delta_disks = rs->delta_disks;2856	cur_raid_devs = mddev->raid_disks;2857 2858	/* Ignore impossible layout change whilst adding/removing disks */2859	if (mddev->delta_disks &&2860	    mddev->layout != mddev->new_layout) {2861		DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);2862		mddev->new_layout = mddev->layout;2863	}2864 2865	/*2866	 * Adjust array size:2867	 *2868	 * - in case of adding disk(s), array size has2869	 *   to grow after the disk adding reshape,2870	 *   which'll happen in the event handler;2871	 *   reshape will happen forward, so space has to2872	 *   be available at the beginning of each disk2873	 *2874	 * - in case of removing disk(s), array size2875	 *   has to shrink before starting the reshape,2876	 *   which'll happen here;2877	 *   reshape will happen backward, so space has to2878	 *   be available at the end of each disk2879	 *2880	 * - data_offset and new_data_offset are2881	 *   adjusted for aforementioned out of place2882	 *   reshaping based on userspace passing in2883	 *   the "data_offset <sectors>" key/value2884	 *   pair via the constructor2885	 */2886 2887	/* Add disk(s) */2888	if (rs->delta_disks > 0) {2889		/* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */2890		for (d = cur_raid_devs; d < rs->raid_disks; d++) {2891			rdev = &rs->dev[d].rdev;2892			clear_bit(In_sync, &rdev->flags);2893 2894			/*2895			 * save_raid_disk needs to be -1, or recovery_offset will be set to 02896			 * by md, which'll store that erroneously in the superblock on reshape2897			 */2898			rdev->saved_raid_disk = -1;2899			rdev->raid_disk = d;2900 2901			rdev->sectors = mddev->dev_sectors;2902			rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;2903		}2904 2905		mddev->reshape_backwards = 0; /* adding disk(s) -> forward reshape */2906 2907	/* Remove disk(s) */2908	} else if (rs->delta_disks < 0) {2909		r = rs_set_dev_and_array_sectors(rs, rs->ti->len, true);2910		mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */2911 2912	/* Change layout and/or chunk size */2913	} else {2914		/*2915		 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:2916		 *2917		 * keeping number of disks and do layout change ->2918		 *2919		 * toggle reshape_backward depending on data_offset:2920		 *2921		 * - free space upfront -> reshape forward2922		 *2923		 * - free space at the end -> reshape backward2924		 *2925		 *2926		 * This utilizes free reshape space avoiding the need2927		 * for userspace to move (parts of) LV segments in2928		 * case of layout/chunksize change  (for disk2929		 * adding/removing reshape space has to be at2930		 * the proper address (see above with delta_disks):2931		 *2932		 * add disk(s)   -> begin2933		 * remove disk(s)-> end2934		 */2935		mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;2936	}2937 2938	/*2939	 * Adjust device size for forward reshape2940	 * because md_finish_reshape() reduces it.2941	 */2942	if (!mddev->reshape_backwards)2943		rdev_for_each(rdev, &rs->md)2944			if (!test_bit(Journal, &rdev->flags))2945				rdev->sectors += reshape_sectors;2946 2947	return r;2948}2949 2950/*2951 * If the md resync thread has updated superblock with max reshape position2952 * at the end of a reshape but not (yet) reset the layout configuration2953 * changes -> reset the latter.2954 */2955static void rs_reset_inconclusive_reshape(struct raid_set *rs)2956{2957	if (!rs_is_reshaping(rs) && rs_is_layout_change(rs, true)) {2958		rs_set_cur(rs);2959		rs->md.delta_disks = 0;2960		rs->md.reshape_backwards = 0;2961	}2962}2963 2964/*2965 * Enable/disable discard support on RAID set depending on2966 * RAID level and discard properties of underlying RAID members.2967 */2968static void configure_discard_support(struct raid_set *rs)2969{2970	int i;2971	bool raid456;2972	struct dm_target *ti = rs->ti;2973 2974	/*2975	 * XXX: RAID level 4,5,6 require zeroing for safety.2976	 */2977	raid456 = rs_is_raid456(rs);2978 2979	for (i = 0; i < rs->raid_disks; i++) {2980		if (!rs->dev[i].rdev.bdev ||2981		    !bdev_max_discard_sectors(rs->dev[i].rdev.bdev))2982			return;2983 2984		if (raid456) {2985			if (!devices_handle_discard_safely) {2986				DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");2987				DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");2988				return;2989			}2990		}2991	}2992 2993	ti->num_discard_bios = 1;2994}2995 2996/*2997 * Construct a RAID0/1/10/4/5/6 mapping:2998 * Args:2999 *	<raid_type> <#raid_params> <raid_params>{0,}	\3000 *	<#raid_devs> [<meta_dev1> <dev1>]{1,}3001 *3002 * <raid_params> varies by <raid_type>.	 See 'parse_raid_params' for3003 * details on possible <raid_params>.3004 *3005 * Userspace is free to initialize the metadata devices, hence the superblocks to3006 * enforce recreation based on the passed in table parameters.3007 *3008 */3009static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)3010{3011	int r;3012	bool resize = false;3013	struct raid_type *rt;3014	unsigned int num_raid_params, num_raid_devs;3015	sector_t sb_array_sectors, rdev_sectors, reshape_sectors;3016	struct raid_set *rs = NULL;3017	const char *arg;3018	struct rs_layout rs_layout;3019	struct dm_arg_set as = { argc, argv }, as_nrd;3020	struct dm_arg _args[] = {3021		{ 0, as.argc, "Cannot understand number of raid parameters" },3022		{ 1, 254, "Cannot understand number of raid devices parameters" }3023	};3024 3025	arg = dm_shift_arg(&as);3026	if (!arg) {3027		ti->error = "No arguments";3028		return -EINVAL;3029	}3030 3031	rt = get_raid_type(arg);3032	if (!rt) {3033		ti->error = "Unrecognised raid_type";3034		return -EINVAL;3035	}3036 3037	/* Must have <#raid_params> */3038	if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))3039		return -EINVAL;3040 3041	/* number of raid device tupples <meta_dev data_dev> */3042	as_nrd = as;3043	dm_consume_args(&as_nrd, num_raid_params);3044	_args[1].max = (as_nrd.argc - 1) / 2;3045	if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))3046		return -EINVAL;3047 3048	if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {3049		ti->error = "Invalid number of supplied raid devices";3050		return -EINVAL;3051	}3052 3053	rs = raid_set_alloc(ti, rt, num_raid_devs);3054	if (IS_ERR(rs))3055		return PTR_ERR(rs);3056 3057	r = parse_raid_params(rs, &as, num_raid_params);3058	if (r)3059		goto bad;3060 3061	r = parse_dev_params(rs, &as);3062	if (r)3063		goto bad;3064 3065	rs->md.sync_super = super_sync;3066 3067	/*3068	 * Calculate ctr requested array and device sizes to allow3069	 * for superblock analysis needing device sizes defined.3070	 *3071	 * Any existing superblock will overwrite the array and device sizes3072	 */3073	r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);3074	if (r)3075		goto bad;3076 3077	/* Memorize just calculated, potentially larger sizes to grow the raid set in preresume */3078	rs->array_sectors = rs->md.array_sectors;3079	rs->dev_sectors = rs->md.dev_sectors;3080 3081	/*3082	 * Backup any new raid set level, layout, ...3083	 * requested to be able to compare to superblock3084	 * members for conversion decisions.3085	 */3086	rs_config_backup(rs, &rs_layout);3087 3088	r = analyse_superblocks(ti, rs);3089	if (r)3090		goto bad;3091 3092	/* All in-core metadata now as of current superblocks after calling analyse_superblocks() */3093	sb_array_sectors = rs->md.array_sectors;3094	rdev_sectors = __rdev_sectors(rs);3095	if (!rdev_sectors) {3096		ti->error = "Invalid rdev size";3097		r = -EINVAL;3098		goto bad;3099	}3100 3101 3102	reshape_sectors = _get_reshape_sectors(rs);3103	if (rs->dev_sectors != rdev_sectors) {3104		resize = (rs->dev_sectors != rdev_sectors - reshape_sectors);3105		if (rs->dev_sectors > rdev_sectors - reshape_sectors)3106			set_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);3107	}3108 3109	INIT_WORK(&rs->md.event_work, do_table_event);3110	ti->private = rs;3111	ti->num_flush_bios = 1;3112	ti->needs_bio_set_dev = true;3113 3114	/* Restore any requested new layout for conversion decision */3115	rs_config_restore(rs, &rs_layout);3116 3117	/*3118	 * Now that we have any superblock metadata available,3119	 * check for new, recovering, reshaping, to be taken over,3120	 * to be reshaped or an existing, unchanged raid set to3121	 * run in sequence.3122	 */3123	if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {3124		/* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */3125		if (rs_is_raid6(rs) &&3126		    test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {3127			ti->error = "'nosync' not allowed for new raid6 set";3128			r = -EINVAL;3129			goto bad;3130		}3131		rs_setup_recovery(rs, 0);3132		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);3133		rs_set_new(rs);3134	} else if (rs_is_recovering(rs)) {3135		/* A recovering raid set may be resized */3136		goto size_check;3137	} else if (rs_is_reshaping(rs)) {3138		/* Have to reject size change request during reshape */3139		if (resize) {3140			ti->error = "Can't resize a reshaping raid set";3141			r = -EPERM;3142			goto bad;3143		}3144		/* skip setup rs */3145	} else if (rs_takeover_requested(rs)) {3146		if (rs_is_reshaping(rs)) {3147			ti->error = "Can't takeover a reshaping raid set";3148			r = -EPERM;3149			goto bad;3150		}3151 3152		/* We can't takeover a journaled raid4/5/6 */3153		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {3154			ti->error = "Can't takeover a journaled raid4/5/6 set";3155			r = -EPERM;3156			goto bad;3157		}3158 3159		/*3160		 * If a takeover is needed, userspace sets any additional3161		 * devices to rebuild and we can check for a valid request here.3162		 *3163		 * If acceptable, set the level to the new requested3164		 * one, prohibit requesting recovery, allow the raid3165		 * set to run and store superblocks during resume.3166		 */3167		r = rs_check_takeover(rs);3168		if (r)3169			goto bad;3170 3171		r = rs_setup_takeover(rs);3172		if (r)3173			goto bad;3174 3175		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);3176		/* Takeover ain't recovery, so disable recovery */3177		rs_setup_recovery(rs, MaxSector);3178		rs_set_new(rs);3179	} else if (rs_reshape_requested(rs)) {3180		/* Only request grow on raid set size extensions, not on reshapes. */3181		clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);3182 3183		/*3184		 * No need to check for 'ongoing' takeover here, because takeover3185		 * is an instant operation as oposed to an ongoing reshape.3186		 */3187 3188		/* We can't reshape a journaled raid4/5/6 */3189		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {3190			ti->error = "Can't reshape a journaled raid4/5/6 set";3191			r = -EPERM;3192			goto bad;3193		}3194 3195		/* Out-of-place space has to be available to allow for a reshape unless raid1! */3196		if (reshape_sectors || rs_is_raid1(rs)) {3197			/*3198			 * We can only prepare for a reshape here, because the3199			 * raid set needs to run to provide the repective reshape3200			 * check functions via its MD personality instance.3201			 *3202			 * So do the reshape check after md_run() succeeded.3203			 */3204			r = rs_prepare_reshape(rs);3205			if (r)3206				goto bad;3207 3208			/* Reshaping ain't recovery, so disable recovery */3209			rs_setup_recovery(rs, MaxSector);3210		}3211		rs_set_cur(rs);3212	} else {3213size_check:3214		/* May not set recovery when a device rebuild is requested */3215		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {3216			clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);3217			set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);3218			rs_setup_recovery(rs, MaxSector);3219		} else if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {3220			/*3221			 * Set raid set to current size, i.e. size as of3222			 * superblocks to grow to larger size in preresume.3223			 */3224			r = rs_set_dev_and_array_sectors(rs, sb_array_sectors, false);3225			if (r)3226				goto bad;3227 3228			rs_setup_recovery(rs, rs->md.recovery_cp < rs->md.dev_sectors ? rs->md.recovery_cp : rs->md.dev_sectors);3229		} else {3230			/* This is no size change or it is shrinking, update size and record in superblocks */3231			r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);3232			if (r)3233				goto bad;3234 3235			if (sb_array_sectors > rs->array_sectors)3236				set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);3237		}3238		rs_set_cur(rs);3239	}3240 3241	/* If constructor requested it, change data and new_data offsets */3242	r = rs_adjust_data_offsets(rs);3243	if (r)3244		goto bad;3245 3246	/* Catch any inconclusive reshape superblock content. */3247	rs_reset_inconclusive_reshape(rs);3248 3249	/* Start raid set read-only and assumed clean to change in raid_resume() */3250	rs->md.ro = 1;3251	rs->md.in_sync = 1;3252 3253	/* Has to be held on running the array */3254	mddev_suspend_and_lock_nointr(&rs->md);3255 3256	/* Keep array frozen until resume. */3257	md_frozen_sync_thread(&rs->md);3258 3259	r = md_run(&rs->md);3260	rs->md.in_sync = 0; /* Assume already marked dirty */3261	if (r) {3262		ti->error = "Failed to run raid array";3263		mddev_unlock(&rs->md);3264		goto bad;3265	}3266 3267	r = md_start(&rs->md);3268	if (r) {3269		ti->error = "Failed to start raid array";3270		goto bad_unlock;3271	}3272 3273	/* If raid4/5/6 journal mode explicitly requested (only possible with journal dev) -> set it */3274	if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {3275		r = r5c_journal_mode_set(&rs->md, rs->journal_dev.mode);3276		if (r) {3277			ti->error = "Failed to set raid4/5/6 journal mode";3278			goto bad_unlock;3279		}3280	}3281 3282	set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags);3283 3284	/* Try to adjust the raid4/5/6 stripe cache size to the stripe size */3285	if (rs_is_raid456(rs)) {3286		r = rs_set_raid456_stripe_cache(rs);3287		if (r)3288			goto bad_unlock;3289	}3290 3291	/* Now do an early reshape check */3292	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {3293		r = rs_check_reshape(rs);3294		if (r)3295			goto bad_unlock;3296 3297		/* Restore new, ctr requested layout to perform check */3298		rs_config_restore(rs, &rs_layout);3299 3300		if (rs->md.pers->start_reshape) {3301			r = rs->md.pers->check_reshape(&rs->md);3302			if (r) {3303				ti->error = "Reshape check failed";3304				goto bad_unlock;3305			}3306		}3307	}3308 3309	/* Disable/enable discard support on raid set. */3310	configure_discard_support(rs);3311 3312	mddev_unlock(&rs->md);3313	return 0;3314 3315bad_unlock:3316	md_stop(&rs->md);3317	mddev_unlock(&rs->md);3318bad:3319	raid_set_free(rs);3320 3321	return r;3322}3323 3324static void raid_dtr(struct dm_target *ti)3325{3326	struct raid_set *rs = ti->private;3327 3328	mddev_lock_nointr(&rs->md);3329	md_stop(&rs->md);3330	mddev_unlock(&rs->md);3331 3332	if (work_pending(&rs->md.event_work))3333		flush_work(&rs->md.event_work);3334	raid_set_free(rs);3335}3336 3337static int raid_map(struct dm_target *ti, struct bio *bio)3338{3339	struct raid_set *rs = ti->private;3340	struct mddev *mddev = &rs->md;3341 3342	/*3343	 * If we're reshaping to add disk(s), ti->len and3344	 * mddev->array_sectors will differ during the process3345	 * (ti->len > mddev->array_sectors), so we have to requeue3346	 * bios with addresses > mddev->array_sectors here or3347	 * there will occur accesses past EOD of the component3348	 * data images thus erroring the raid set.3349	 */3350	if (unlikely(bio_has_data(bio) && bio_end_sector(bio) > mddev->array_sectors))3351		return DM_MAPIO_REQUEUE;3352 3353	if (unlikely(!md_handle_request(mddev, bio)))3354		return DM_MAPIO_REQUEUE;3355 3356	return DM_MAPIO_SUBMITTED;3357}3358 3359/* Return sync state string for @state */3360enum sync_state { st_frozen, st_reshape, st_resync, st_check, st_repair, st_recover, st_idle };3361static const char *sync_str(enum sync_state state)3362{3363	/* Has to be in above sync_state order! */3364	static const char *sync_strs[] = {3365		"frozen",3366		"reshape",3367		"resync",3368		"check",3369		"repair",3370		"recover",3371		"idle"3372	};3373 3374	return __within_range(state, 0, ARRAY_SIZE(sync_strs) - 1) ? sync_strs[state] : "undef";3375};3376 3377/* Return enum sync_state for @mddev derived from @recovery flags */3378static enum sync_state decipher_sync_action(struct mddev *mddev, unsigned long recovery)3379{3380	if (test_bit(MD_RECOVERY_FROZEN, &recovery))3381		return st_frozen;3382 3383	/* The MD sync thread can be done with io or be interrupted but still be running */3384	if (!test_bit(MD_RECOVERY_DONE, &recovery) &&3385	    (test_bit(MD_RECOVERY_RUNNING, &recovery) ||3386	     (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery)))) {3387		if (test_bit(MD_RECOVERY_RESHAPE, &recovery))3388			return st_reshape;3389 3390		if (test_bit(MD_RECOVERY_SYNC, &recovery)) {3391			if (!test_bit(MD_RECOVERY_REQUESTED, &recovery))3392				return st_resync;3393			if (test_bit(MD_RECOVERY_CHECK, &recovery))3394				return st_check;3395			return st_repair;3396		}3397 3398		if (test_bit(MD_RECOVERY_RECOVER, &recovery))3399			return st_recover;3400 3401		if (mddev->reshape_position != MaxSector)3402			return st_reshape;3403	}3404 3405	return st_idle;3406}3407 3408/*3409 * Return status string for @rdev3410 *3411 * Status characters:3412 *3413 *  'D' = Dead/Failed raid set component or raid4/5/6 journal device3414 *  'a' = Alive but not in-sync raid set component _or_ alive raid4/5/6 'write_back' journal device3415 *  'A' = Alive and in-sync raid set component _or_ alive raid4/5/6 'write_through' journal device3416 *  '-' = Non-existing device (i.e. uspace passed '- -' into the ctr)3417 */3418static const char *__raid_dev_status(struct raid_set *rs, struct md_rdev *rdev)3419{3420	if (!rdev->bdev)3421		return "-";3422	else if (test_bit(Faulty, &rdev->flags))3423		return "D";3424	else if (test_bit(Journal, &rdev->flags))3425		return (rs->journal_dev.mode == R5C_JOURNAL_MODE_WRITE_THROUGH) ? "A" : "a";3426	else if (test_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags) ||3427		 (!test_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags) &&3428		  !test_bit(In_sync, &rdev->flags)))3429		return "a";3430	else3431		return "A";3432}3433 3434/* Helper to return resync/reshape progress for @rs and runtime flags for raid set in sync / resynching */3435static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery,3436				enum sync_state state, sector_t resync_max_sectors)3437{3438	sector_t r;3439	struct mddev *mddev = &rs->md;3440 3441	clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);3442	clear_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);3443 3444	if (rs_is_raid0(rs)) {3445		r = resync_max_sectors;3446		set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);3447 3448	} else {3449		if (state == st_idle && !test_bit(MD_RECOVERY_INTR, &recovery))3450			r = mddev->recovery_cp;3451		else3452			r = mddev->curr_resync_completed;3453 3454		if (state == st_idle && r >= resync_max_sectors) {3455			/*3456			 * Sync complete.3457			 */3458			/* In case we have finished recovering, the array is in sync. */3459			if (test_bit(MD_RECOVERY_RECOVER, &recovery))3460				set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);3461 3462		} else if (state == st_recover)3463			/*3464			 * In case we are recovering, the array is not in sync3465			 * and health chars should show the recovering legs.3466			 *3467			 * Already retrieved recovery offset from curr_resync_completed above.3468			 */3469			;3470 3471		else if (state == st_resync || state == st_reshape)3472			/*3473			 * If "resync/reshape" is occurring, the raid set3474			 * is or may be out of sync hence the health3475			 * characters shall be 'a'.3476			 */3477			set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);3478 3479		else if (state == st_check || state == st_repair)3480			/*3481			 * If "check" or "repair" is occurring, the raid set has3482			 * undergone an initial sync and the health characters3483			 * should not be 'a' anymore.3484			 */3485			set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);3486 3487		else if (test_bit(MD_RECOVERY_NEEDED, &recovery))3488			/*3489			 * We are idle and recovery is needed, prevent 'A' chars race3490			 * caused by components still set to in-sync by constructor.3491			 */3492			set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);3493 3494		else {3495			/*3496			 * We are idle and the raid set may be doing an initial3497			 * sync, or it may be rebuilding individual components.3498			 * If all the devices are In_sync, then it is the raid set3499			 * that is being initialized.3500			 */3501			struct md_rdev *rdev;3502 3503			set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);3504			rdev_for_each(rdev, mddev)3505				if (!test_bit(Journal, &rdev->flags) &&3506				    !test_bit(In_sync, &rdev->flags)) {3507					clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);3508					break;3509				}3510		}3511	}3512 3513	return min(r, resync_max_sectors);3514}3515 3516/* Helper to return @dev name or "-" if !@dev */3517static const char *__get_dev_name(struct dm_dev *dev)3518{3519	return dev ? dev->name : "-";3520}3521 3522static void raid_status(struct dm_target *ti, status_type_t type,3523			unsigned int status_flags, char *result, unsigned int maxlen)3524{3525	struct raid_set *rs = ti->private;3526	struct mddev *mddev = &rs->md;3527	struct r5conf *conf = rs_is_raid456(rs) ? mddev->private : NULL;3528	int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;3529	unsigned long recovery;3530	unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */3531	unsigned int sz = 0;3532	unsigned int rebuild_writemostly_count = 0;3533	sector_t progress, resync_max_sectors, resync_mismatches;3534	enum sync_state state;3535	struct raid_type *rt;3536 3537	switch (type) {3538	case STATUSTYPE_INFO:3539		/* *Should* always succeed */3540		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);3541		if (!rt)3542			return;3543 3544		DMEMIT("%s %d ", rt->name, mddev->raid_disks);3545 3546		/* Access most recent mddev properties for status output */3547		smp_rmb();3548		/* Get sensible max sectors even if raid set not yet started */3549		resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?3550				      mddev->resync_max_sectors : mddev->dev_sectors;3551		recovery = rs->md.recovery;3552		state = decipher_sync_action(mddev, recovery);3553		progress = rs_get_progress(rs, recovery, state, resync_max_sectors);3554		resync_mismatches = mddev->last_sync_action == ACTION_CHECK ?3555				    atomic64_read(&mddev->resync_mismatches) : 0;3556 3557		/* HM FIXME: do we want another state char for raid0? It shows 'D'/'A'/'-' now */3558		for (i = 0; i < rs->raid_disks; i++)3559			DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));3560 3561		/*3562		 * In-sync/Reshape ratio:3563		 *  The in-sync ratio shows the progress of:3564		 *   - Initializing the raid set3565		 *   - Rebuilding a subset of devices of the raid set3566		 *  The user can distinguish between the two by referring3567		 *  to the status characters.3568		 *3569		 *  The reshape ratio shows the progress of3570		 *  changing the raid layout or the number of3571		 *  disks of a raid set3572		 */3573		DMEMIT(" %llu/%llu", (unsigned long long) progress,3574				     (unsigned long long) resync_max_sectors);3575 3576		/*3577		 * v1.5.0+:3578		 *3579		 * Sync action:3580		 *   See Documentation/admin-guide/device-mapper/dm-raid.rst for3581		 *   information on each of these states.3582		 */3583		DMEMIT(" %s", sync_str(state));3584 3585		/*3586		 * v1.5.0+:3587		 *3588		 * resync_mismatches/mismatch_cnt3589		 *   This field shows the number of discrepancies found when3590		 *   performing a "check" of the raid set.3591		 */3592		DMEMIT(" %llu", (unsigned long long) resync_mismatches);3593 3594		/*3595		 * v1.9.0+:3596		 *3597		 * data_offset (needed for out of space reshaping)3598		 *   This field shows the data offset into the data3599		 *   image LV where the first stripes data starts.3600		 *3601		 * We keep data_offset equal on all raid disks of the set,3602		 * so retrieving it from the first raid disk is sufficient.3603		 */3604		DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);3605 3606		/*3607		 * v1.10.0+:3608		 */3609		DMEMIT(" %s", test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags) ?3610			      __raid_dev_status(rs, &rs->journal_dev.rdev) : "-");3611		break;3612 3613	case STATUSTYPE_TABLE:3614		/* Report the table line string you would use to construct this raid set */3615 3616		/*3617		 * Count any rebuild or writemostly argument pairs and subtract the3618		 * hweight count being added below of any rebuild and writemostly ctr flags.3619		 */3620		for (i = 0; i < rs->raid_disks; i++) {3621			rebuild_writemostly_count += (test_bit(i, (void *) rs->rebuild_disks) ? 2 : 0) +3622						     (test_bit(WriteMostly, &rs->dev[i].rdev.flags) ? 2 : 0);3623		}3624		rebuild_writemostly_count -= (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) ? 2 : 0) +3625					     (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags) ? 2 : 0);3626		/* Calculate raid parameter count based on ^ rebuild/writemostly argument counts and ctr flags set. */3627		raid_param_cnt += rebuild_writemostly_count +3628				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +3629				  hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;3630		/* Emit table line */3631		/* This has to be in the documented order for userspace! */3632		DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);3633		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))3634			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));3635		if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))3636			DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));3637		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags))3638			for (i = 0; i < rs->raid_disks; i++)3639				if (test_bit(i, (void *) rs->rebuild_disks))3640					DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD), i);3641		if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))3642			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),3643					  mddev->bitmap_info.daemon_sleep);3644		if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))3645			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),3646					 mddev->sync_speed_min);3647		if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))3648			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),3649					 mddev->sync_speed_max);3650		if (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags))3651			for (i = 0; i < rs->raid_disks; i++)3652				if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))3653					DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),3654					       rs->dev[i].rdev.raid_disk);3655		if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))3656			DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),3657					  mddev->bitmap_info.max_write_behind);3658		if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))3659			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),3660					 max_nr_stripes);3661		if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))3662			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),3663					   (unsigned long long) to_sector(mddev->bitmap_info.chunksize));3664		if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))3665			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),3666					 raid10_md_layout_to_copies(mddev->layout));3667		if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))3668			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),3669					 raid10_md_layout_to_format(mddev->layout));3670		if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))3671			DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),3672					 max(rs->delta_disks, mddev->delta_disks));3673		if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))3674			DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),3675					   (unsigned long long) rs->data_offset);3676		if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags))3677			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV),3678					__get_dev_name(rs->journal_dev.dev));3679		if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags))3680			DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE),3681					 md_journal_mode_to_dm_raid(rs->journal_dev.mode));3682		DMEMIT(" %d", rs->raid_disks);3683		for (i = 0; i < rs->raid_disks; i++)3684			DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),3685					 __get_dev_name(rs->dev[i].data_dev));3686		break;3687 3688	case STATUSTYPE_IMA:3689		rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);3690		if (!rt)3691			return;3692 3693		DMEMIT_TARGET_NAME_VERSION(ti->type);3694		DMEMIT(",raid_type=%s,raid_disks=%d", rt->name, mddev->raid_disks);3695 3696		/* Access most recent mddev properties for status output */3697		smp_rmb();3698		recovery = rs->md.recovery;3699		state = decipher_sync_action(mddev, recovery);3700		DMEMIT(",raid_state=%s", sync_str(state));3701 3702		for (i = 0; i < rs->raid_disks; i++) {3703			DMEMIT(",raid_device_%d_status=", i);3704			DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));3705		}3706 3707		if (rt_is_raid456(rt)) {3708			DMEMIT(",journal_dev_mode=");3709			switch (rs->journal_dev.mode) {3710			case R5C_JOURNAL_MODE_WRITE_THROUGH:3711				DMEMIT("%s",3712				       _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_THROUGH].param);3713				break;3714			case R5C_JOURNAL_MODE_WRITE_BACK:3715				DMEMIT("%s",3716				       _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_BACK].param);3717				break;3718			default:3719				DMEMIT("invalid");3720				break;3721			}3722		}3723		DMEMIT(";");3724		break;3725	}3726}3727 3728static int raid_message(struct dm_target *ti, unsigned int argc, char **argv,3729			char *result, unsigned int maxlen)3730{3731	struct raid_set *rs = ti->private;3732	struct mddev *mddev = &rs->md;3733	int ret = 0;3734 3735	if (!mddev->pers || !mddev->pers->sync_request)3736		return -EINVAL;3737 3738	if (test_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags) ||3739	    test_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags))3740		return -EBUSY;3741 3742	if (!strcasecmp(argv[0], "frozen")) {3743		ret = mddev_lock(mddev);3744		if (ret)3745			return ret;3746 3747		md_frozen_sync_thread(mddev);3748		mddev_unlock(mddev);3749	} else if (!strcasecmp(argv[0], "idle")) {3750		ret = mddev_lock(mddev);3751		if (ret)3752			return ret;3753 3754		md_idle_sync_thread(mddev);3755		mddev_unlock(mddev);3756	}3757 3758	clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);3759	if (decipher_sync_action(mddev, mddev->recovery) != st_idle)3760		return -EBUSY;3761	else if (!strcasecmp(argv[0], "resync"))3762		; /* MD_RECOVERY_NEEDED set below */3763	else if (!strcasecmp(argv[0], "recover"))3764		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);3765	else {3766		if (!strcasecmp(argv[0], "check")) {3767			set_bit(MD_RECOVERY_CHECK, &mddev->recovery);3768			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);3769			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);3770		} else if (!strcasecmp(argv[0], "repair")) {3771			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);3772			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);3773		} else3774			return -EINVAL;3775	}3776	if (mddev->ro == 2) {3777		/* A write to sync_action is enough to justify3778		 * canceling read-auto mode3779		 */3780		mddev->ro = 0;3781		if (!mddev->suspended)3782			md_wakeup_thread(mddev->sync_thread);3783	}3784	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);3785	if (!mddev->suspended)3786		md_wakeup_thread(mddev->thread);3787 3788	return 0;3789}3790 3791static int raid_iterate_devices(struct dm_target *ti,3792				iterate_devices_callout_fn fn, void *data)3793{3794	struct raid_set *rs = ti->private;3795	unsigned int i;3796	int r = 0;3797 3798	for (i = 0; !r && i < rs->raid_disks; i++) {3799		if (rs->dev[i].data_dev) {3800			r = fn(ti, rs->dev[i].data_dev,3801			       0, /* No offset on data devs */3802			       rs->md.dev_sectors, data);3803		}3804	}3805 3806	return r;3807}3808 3809static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)3810{3811	struct raid_set *rs = ti->private;3812	unsigned int chunk_size_bytes = to_bytes(rs->md.chunk_sectors);3813 3814	limits->io_min = chunk_size_bytes;3815	limits->io_opt = chunk_size_bytes * mddev_data_stripes(rs);3816}3817 3818static void raid_presuspend(struct dm_target *ti)3819{3820	struct raid_set *rs = ti->private;3821	struct mddev *mddev = &rs->md;3822 3823	/*3824	 * From now on, disallow raid_message() to change sync_thread until3825	 * resume, raid_postsuspend() is too late.3826	 */3827	set_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags);3828 3829	if (!reshape_interrupted(mddev))3830		return;3831 3832	/*3833	 * For raid456, if reshape is interrupted, IO across reshape position3834	 * will never make progress, while caller will wait for IO to be done.3835	 * Inform raid456 to handle those IO to prevent deadlock.3836	 */3837	if (mddev->pers && mddev->pers->prepare_suspend)3838		mddev->pers->prepare_suspend(mddev);3839}3840 3841static void raid_presuspend_undo(struct dm_target *ti)3842{3843	struct raid_set *rs = ti->private;3844 3845	clear_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags);3846}3847 3848static void raid_postsuspend(struct dm_target *ti)3849{3850	struct raid_set *rs = ti->private;3851 3852	if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {3853		/*3854		 * sync_thread must be stopped during suspend, and writes have3855		 * to be stopped before suspending to avoid deadlocks.3856		 */3857		md_stop_writes(&rs->md);3858		mddev_suspend(&rs->md, false);3859	}3860}3861 3862static void attempt_restore_of_faulty_devices(struct raid_set *rs)3863{3864	int i;3865	uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];3866	unsigned long flags;3867	bool cleared = false;3868	struct dm_raid_superblock *sb;3869	struct mddev *mddev = &rs->md;3870	struct md_rdev *r;3871 3872	/* RAID personalities have to provide hot add/remove methods or we need to bail out. */3873	if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)3874		return;3875 3876	memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));3877 3878	for (i = 0; i < rs->raid_disks; i++) {3879		r = &rs->dev[i].rdev;3880		/* HM FIXME: enhance journal device recovery processing */3881		if (test_bit(Journal, &r->flags))3882			continue;3883 3884		if (test_bit(Faulty, &r->flags) &&3885		    r->meta_bdev && !read_disk_sb(r, r->sb_size, true)) {3886			DMINFO("Faulty %s device #%d has readable super block."3887			       "  Attempting to revive it.",3888			       rs->raid_type->name, i);3889 3890			/*3891			 * Faulty bit may be set, but sometimes the array can3892			 * be suspended before the personalities can respond3893			 * by removing the device from the array (i.e. calling3894			 * 'hot_remove_disk').	If they haven't yet removed3895			 * the failed device, its 'raid_disk' number will be3896			 * '>= 0' - meaning we must call this function3897			 * ourselves.3898			 */3899			flags = r->flags;3900			clear_bit(In_sync, &r->flags); /* Mandatory for hot remove. */3901			if (r->raid_disk >= 0) {3902				if (mddev->pers->hot_remove_disk(mddev, r)) {3903					/* Failed to revive this device, try next */3904					r->flags = flags;3905					continue;3906				}3907			} else3908				r->raid_disk = r->saved_raid_disk = i;3909 3910			clear_bit(Faulty, &r->flags);3911			clear_bit(WriteErrorSeen, &r->flags);3912 3913			if (mddev->pers->hot_add_disk(mddev, r)) {3914				/* Failed to revive this device, try next */3915				r->raid_disk = r->saved_raid_disk = -1;3916				r->flags = flags;3917			} else {3918				clear_bit(In_sync, &r->flags);3919				r->recovery_offset = 0;3920				set_bit(i, (void *) cleared_failed_devices);3921				cleared = true;3922			}3923		}3924	}3925 3926	/* If any failed devices could be cleared, update all sbs failed_devices bits */3927	if (cleared) {3928		uint64_t failed_devices[DISKS_ARRAY_ELEMS];3929 3930		rdev_for_each(r, &rs->md) {3931			if (test_bit(Journal, &r->flags))3932				continue;3933 3934			sb = page_address(r->sb_page);3935			sb_retrieve_failed_devices(sb, failed_devices);3936 3937			for (i = 0; i < DISKS_ARRAY_ELEMS; i++)3938				failed_devices[i] &= ~cleared_failed_devices[i];3939 3940			sb_update_failed_devices(sb, failed_devices);3941		}3942	}3943}3944 3945static int __load_dirty_region_bitmap(struct raid_set *rs)3946{3947	int r = 0;3948 3949	/* Try loading the bitmap unless "raid0", which does not have one */3950	if (!rs_is_raid0(rs) &&3951	    !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {3952		struct mddev *mddev = &rs->md;3953 3954		r = mddev->bitmap_ops->load(mddev);3955		if (r)3956			DMERR("Failed to load bitmap");3957	}3958 3959	return r;3960}3961 3962/* Enforce updating all superblocks */3963static void rs_update_sbs(struct raid_set *rs)3964{3965	struct mddev *mddev = &rs->md;3966	int ro = mddev->ro;3967 3968	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);3969	mddev->ro = 0;3970	md_update_sb(mddev, 1);3971	mddev->ro = ro;3972}3973 3974/*3975 * Reshape changes raid algorithm of @rs to new one within personality3976 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes3977 * disks from a raid set thus growing/shrinking it or resizes the set3978 *3979 * Call mddev_lock_nointr() before!3980 */3981static int rs_start_reshape(struct raid_set *rs)3982{3983	int r;3984	struct mddev *mddev = &rs->md;3985	struct md_personality *pers = mddev->pers;3986 3987	/* Don't allow the sync thread to work until the table gets reloaded. */3988	set_bit(MD_RECOVERY_WAIT, &mddev->recovery);3989 3990	r = rs_setup_reshape(rs);3991	if (r)3992		return r;3993 3994	/*3995	 * Check any reshape constraints enforced by the personalility3996	 *3997	 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.3998	 */3999	r = pers->check_reshape(mddev);4000	if (r) {4001		rs->ti->error = "pers->check_reshape() failed";4002		return r;4003	}4004 4005	/*4006	 * Personality may not provide start reshape method in which4007	 * case check_reshape above has already covered everything4008	 */4009	if (pers->start_reshape) {4010		r = pers->start_reshape(mddev);4011		if (r) {4012			rs->ti->error = "pers->start_reshape() failed";4013			return r;4014		}4015	}4016 4017	/*4018	 * Now reshape got set up, update superblocks to4019	 * reflect the fact so that a table reload will4020	 * access proper superblock content in the ctr.4021	 */4022	rs_update_sbs(rs);4023 4024	return 0;4025}4026 4027static int raid_preresume(struct dm_target *ti)4028{4029	int r;4030	struct raid_set *rs = ti->private;4031	struct mddev *mddev = &rs->md;4032 4033	/* This is a resume after a suspend of the set -> it's already started. */4034	if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))4035		return 0;4036 4037	/* If different and no explicit grow request, expose MD array size as of superblock. */4038	if (!test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags) &&4039	    rs->array_sectors != mddev->array_sectors)4040		rs_set_capacity(rs);4041 4042	/*4043	 * The superblocks need to be updated on disk if the4044	 * array is new or new devices got added (thus zeroed4045	 * out by userspace) or __load_dirty_region_bitmap4046	 * will overwrite them in core with old data or fail.4047	 */4048	if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))4049		rs_update_sbs(rs);4050 4051	/* Load the bitmap from disk unless raid0 */4052	r = __load_dirty_region_bitmap(rs);4053	if (r)4054		return r;4055 4056	/* We are extending the raid set size, adjust mddev/md_rdev sizes and set capacity. */4057	if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {4058		mddev->array_sectors = rs->array_sectors;4059		mddev->dev_sectors = rs->dev_sectors;4060		rs_set_rdev_sectors(rs);4061		rs_set_capacity(rs);4062	}4063 4064	/* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) or grown device size */4065	if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&4066	    (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags) ||4067	     (rs->requested_bitmap_chunk_sectors &&4068	       mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)))) {4069		int chunksize = to_bytes(rs->requested_bitmap_chunk_sectors) ?: mddev->bitmap_info.chunksize;4070 4071		r = mddev->bitmap_ops->resize(mddev, mddev->dev_sectors,4072					      chunksize, false);4073		if (r)4074			DMERR("Failed to resize bitmap");4075	}4076 4077	/* Check for any resize/reshape on @rs and adjust/initiate */4078	if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {4079		set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);4080		mddev->resync_min = mddev->recovery_cp;4081		if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags))4082			mddev->resync_max_sectors = mddev->dev_sectors;4083	}4084 4085	/* Check for any reshape request unless new raid set */4086	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {4087		/* Initiate a reshape. */4088		rs_set_rdev_sectors(rs);4089		mddev_lock_nointr(mddev);4090		r = rs_start_reshape(rs);4091		mddev_unlock(mddev);4092		if (r)4093			DMWARN("Failed to check/start reshape, continuing without change");4094		r = 0;4095	}4096 4097	return r;4098}4099 4100static void raid_resume(struct dm_target *ti)4101{4102	struct raid_set *rs = ti->private;4103	struct mddev *mddev = &rs->md;4104 4105	if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {4106		/*4107		 * A secondary resume while the device is active.4108		 * Take this opportunity to check whether any failed4109		 * devices are reachable again.4110		 */4111		mddev_lock_nointr(mddev);4112		attempt_restore_of_faulty_devices(rs);4113		mddev_unlock(mddev);4114	}4115 4116	if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {4117		/* Only reduce raid set size before running a disk removing reshape. */4118		if (mddev->delta_disks < 0)4119			rs_set_capacity(rs);4120 4121		mddev_lock_nointr(mddev);4122		WARN_ON_ONCE(!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery));4123		WARN_ON_ONCE(rcu_dereference_protected(mddev->sync_thread,4124						       lockdep_is_held(&mddev->reconfig_mutex)));4125		clear_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags);4126		mddev->ro = 0;4127		mddev->in_sync = 0;4128		md_unfrozen_sync_thread(mddev);4129		mddev_unlock_and_resume(mddev);4130	}4131}4132 4133static struct target_type raid_target = {4134	.name = "raid",4135	.version = {1, 15, 1},4136	.module = THIS_MODULE,4137	.ctr = raid_ctr,4138	.dtr = raid_dtr,4139	.map = raid_map,4140	.status = raid_status,4141	.message = raid_message,4142	.iterate_devices = raid_iterate_devices,4143	.io_hints = raid_io_hints,4144	.presuspend = raid_presuspend,4145	.presuspend_undo = raid_presuspend_undo,4146	.postsuspend = raid_postsuspend,4147	.preresume = raid_preresume,4148	.resume = raid_resume,4149};4150module_dm(raid);4151 4152module_param(devices_handle_discard_safely, bool, 0644);4153MODULE_PARM_DESC(devices_handle_discard_safely,4154		 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");4155 4156MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");4157MODULE_ALIAS("dm-raid0");4158MODULE_ALIAS("dm-raid1");4159MODULE_ALIAS("dm-raid10");4160MODULE_ALIAS("dm-raid4");4161MODULE_ALIAS("dm-raid5");4162MODULE_ALIAS("dm-raid6");4163MODULE_AUTHOR("Neil Brown <dm-devel@lists.linux.dev>");4164MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@lists.linux.dev>");4165MODULE_LICENSE("GPL");4166