1	// SPDX-License-Identifier: GPL-2.0-only
2	/*
3	* Copyright (C) 2010-2011 Neil Brown
4	* Copyright (C) 2010-2018 Red Hat, Inc. All rights reserved.
5	*
6	* This file is released under the GPL.
7	*/
8
9	#include <linux/slab.h>
10	#include <linux/module.h>
11
12	#include "md.h"
13	#include "raid1.h"
14	#include "raid5.h"
15	#include "raid10.h"
16	#include "md-bitmap.h"
17
18	#include <linux/device-mapper.h>
19
20	#define DM_MSG_PREFIX "raid"
21	#define MAX_RAID_DEVICES 253 /* md-raid kernel limit */
22
23	/*
24	* Minimum sectors of free reshape space per raid device
25	*/
26	#define MIN_FREE_RESHAPE_SPACE to_sector(4*4096)
27
28	/*
29	* Minimum journal space 4 MiB in sectors.
30	*/
31	#define MIN_RAID456_JOURNAL_SPACE (4*2048)
32
33	static 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
41	struct raid_dev {
42	/*
43	* Two DM devices, one to hold metadata and one to hold the
44	* actual data/parity. The reason for this is to not confuse
45	* ti->len and give more flexibility in altering size and
46	* characteristics.
47	*
48	* While it is possible for this device to be associated
49	* with a different physical device than the data_dev, it
50	* is intended for it to be the same.
51	* |--------- Physical Device ---------|
52	* |- meta_dev -|------ data_dev ------|
53	*/
54	struct dm_dev *meta_dev;
55	struct dm_dev *data_dev;
56	struct md_rdev rdev;
57	};
58
59	/*
60	* Bits for establishing rs->ctr_flags
61	*
62	* 1 = no flag value
63	* 2 = flag with value
64	*/
65	#define __CTR_FLAG_SYNC 0 /* 1 */ /* Not with raid0! */
66	#define __CTR_FLAG_NOSYNC 1 /* 1 */ /* Not with raid0! */
67	#define __CTR_FLAG_REBUILD 2 /* 2 */ /* Not with raid0! */
68	#define __CTR_FLAG_DAEMON_SLEEP 3 /* 2 */ /* Not with raid0! */
69	#define __CTR_FLAG_MIN_RECOVERY_RATE 4 /* 2 */ /* Not with raid0! */
70	#define __CTR_FLAG_MAX_RECOVERY_RATE 5 /* 2 */ /* Not with raid0! */
71	#define __CTR_FLAG_MAX_WRITE_BEHIND 6 /* 2 */ /* Only with raid1! */
72	#define __CTR_FLAG_WRITE_MOSTLY 7 /* 2 */ /* Only with raid1! */
73	#define __CTR_FLAG_STRIPE_CACHE 8 /* 2 */ /* Only with raid4/5/6! */
74	#define __CTR_FLAG_REGION_SIZE 9 /* 2 */ /* Not with raid0! */
75	#define __CTR_FLAG_RAID10_COPIES 10 /* 2 */ /* Only with raid10 */
76	#define __CTR_FLAG_RAID10_FORMAT 11 /* 2 */ /* Only with raid10 */
77	/* New for v1.9.0 */
78	#define __CTR_FLAG_DELTA_DISKS 12 /* 2 */ /* Only with reshapable raid1/4/5/6/10! */
79	#define __CTR_FLAG_DATA_OFFSET 13 /* 2 */ /* Only with reshapable raid4/5/6/10! */
80	#define __CTR_FLAG_RAID10_USE_NEAR_SETS 14 /* 2 */ /* Only with raid10! */
81
82	/* New for v1.10.0 */
83	#define __CTR_FLAG_JOURNAL_DEV 15 /* 2 */ /* Only with raid4/5/6 (journal device)! */
84
85	/* New for v1.11.1 */
86	#define __CTR_FLAG_JOURNAL_MODE 16 /* 2 */ /* Only with raid4/5/6 (journal mode)! */
87
88	/*
89	* Flags for rs->ctr_flags field.
90	*/
91	#define CTR_FLAG_SYNC (1 << __CTR_FLAG_SYNC)
92	#define CTR_FLAG_NOSYNC (1 << __CTR_FLAG_NOSYNC)
93	#define CTR_FLAG_REBUILD (1 << __CTR_FLAG_REBUILD)
94	#define CTR_FLAG_DAEMON_SLEEP (1 << __CTR_FLAG_DAEMON_SLEEP)
95	#define CTR_FLAG_MIN_RECOVERY_RATE (1 << __CTR_FLAG_MIN_RECOVERY_RATE)
96	#define CTR_FLAG_MAX_RECOVERY_RATE (1 << __CTR_FLAG_MAX_RECOVERY_RATE)
97	#define CTR_FLAG_MAX_WRITE_BEHIND (1 << __CTR_FLAG_MAX_WRITE_BEHIND)
98	#define CTR_FLAG_WRITE_MOSTLY (1 << __CTR_FLAG_WRITE_MOSTLY)
99	#define CTR_FLAG_STRIPE_CACHE (1 << __CTR_FLAG_STRIPE_CACHE)
100	#define CTR_FLAG_REGION_SIZE (1 << __CTR_FLAG_REGION_SIZE)
101	#define CTR_FLAG_RAID10_COPIES (1 << __CTR_FLAG_RAID10_COPIES)
102	#define CTR_FLAG_RAID10_FORMAT (1 << __CTR_FLAG_RAID10_FORMAT)
103	#define CTR_FLAG_DELTA_DISKS (1 << __CTR_FLAG_DELTA_DISKS)
104	#define CTR_FLAG_DATA_OFFSET (1 << __CTR_FLAG_DATA_OFFSET)
105	#define CTR_FLAG_RAID10_USE_NEAR_SETS (1 << __CTR_FLAG_RAID10_USE_NEAR_SETS)
106	#define CTR_FLAG_JOURNAL_DEV (1 << __CTR_FLAG_JOURNAL_DEV)
107	#define CTR_FLAG_JOURNAL_MODE (1 << __CTR_FLAG_JOURNAL_MODE)
108
109	/*
110	* Definitions of various constructor flags to
111	* be used in checks of valid / invalid flags
112	* per raid level.
113	*/
114	/* Define all any sync flags */
115	#define CTR_FLAGS_ANY_SYNC (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)
116
117	/* Define flags for options without argument (e.g. 'nosync') */
118	#define CTR_FLAG_OPTIONS_NO_ARGS (CTR_FLAGS_ANY_SYNC | \
119	CTR_FLAG_RAID10_USE_NEAR_SETS)
120
121	/* Define flags for options with one argument (e.g. 'delta_disks +2') */
122	#define CTR_FLAG_OPTIONS_ONE_ARG (CTR_FLAG_REBUILD | \
123	CTR_FLAG_WRITE_MOSTLY | \
124	CTR_FLAG_DAEMON_SLEEP | \
125	CTR_FLAG_MIN_RECOVERY_RATE | \
126	CTR_FLAG_MAX_RECOVERY_RATE | \
127	CTR_FLAG_MAX_WRITE_BEHIND | \
128	CTR_FLAG_STRIPE_CACHE | \
129	CTR_FLAG_REGION_SIZE | \
130	CTR_FLAG_RAID10_COPIES | \
131	CTR_FLAG_RAID10_FORMAT | \
132	CTR_FLAG_DELTA_DISKS | \
133	CTR_FLAG_DATA_OFFSET | \
134	CTR_FLAG_JOURNAL_DEV | \
135	CTR_FLAG_JOURNAL_MODE)
136
137	/* Valid options definitions per raid level... */
138
139	/* "raid0" does only accept data offset */
140	#define RAID0_VALID_FLAGS (CTR_FLAG_DATA_OFFSET)
141
142	/* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */
143	#define RAID1_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
144	CTR_FLAG_REBUILD | \
145	CTR_FLAG_WRITE_MOSTLY | \
146	CTR_FLAG_DAEMON_SLEEP | \
147	CTR_FLAG_MIN_RECOVERY_RATE | \
148	CTR_FLAG_MAX_RECOVERY_RATE | \
149	CTR_FLAG_MAX_WRITE_BEHIND | \
150	CTR_FLAG_REGION_SIZE | \
151	CTR_FLAG_DELTA_DISKS | \
152	CTR_FLAG_DATA_OFFSET)
153
154	/* "raid10" does not accept any raid1 or stripe cache options */
155	#define RAID10_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
156	CTR_FLAG_REBUILD | \
157	CTR_FLAG_DAEMON_SLEEP | \
158	CTR_FLAG_MIN_RECOVERY_RATE | \
159	CTR_FLAG_MAX_RECOVERY_RATE | \
160	CTR_FLAG_REGION_SIZE | \
161	CTR_FLAG_RAID10_COPIES | \
162	CTR_FLAG_RAID10_FORMAT | \
163	CTR_FLAG_DELTA_DISKS | \
164	CTR_FLAG_DATA_OFFSET | \
165	CTR_FLAG_RAID10_USE_NEAR_SETS)
166
167	/*
168	* "raid4/5/6" do not accept any raid1 or raid10 specific options
169	*
170	* "raid6" does not accept "nosync", because it is not guaranteed
171	* that both parity and q-syndrome are being written properly with
172	* any writes
173	*/
174	#define RAID45_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
175	CTR_FLAG_REBUILD | \
176	CTR_FLAG_DAEMON_SLEEP | \
177	CTR_FLAG_MIN_RECOVERY_RATE | \
178	CTR_FLAG_MAX_RECOVERY_RATE | \
179	CTR_FLAG_STRIPE_CACHE | \
180	CTR_FLAG_REGION_SIZE | \
181	CTR_FLAG_DELTA_DISKS | \
182	CTR_FLAG_DATA_OFFSET | \
183	CTR_FLAG_JOURNAL_DEV | \
184	CTR_FLAG_JOURNAL_MODE)
185
186	#define RAID6_VALID_FLAGS (CTR_FLAG_SYNC | \
187	CTR_FLAG_REBUILD | \
188	CTR_FLAG_DAEMON_SLEEP | \
189	CTR_FLAG_MIN_RECOVERY_RATE | \
190	CTR_FLAG_MAX_RECOVERY_RATE | \
191	CTR_FLAG_STRIPE_CACHE | \
192	CTR_FLAG_REGION_SIZE | \
193	CTR_FLAG_DELTA_DISKS | \
194	CTR_FLAG_DATA_OFFSET | \
195	CTR_FLAG_JOURNAL_DEV | \
196	CTR_FLAG_JOURNAL_MODE)
197	/* ...valid options definitions per raid level */
198
199	/*
200	* Flags for rs->runtime_flags field
201	* (RT_FLAG prefix meaning "runtime flag")
202	*
203	* These are all internal and used to define runtime state,
204	* e.g. to prevent another resume from preresume processing
205	* the raid set all over again.
206	*/
207	#define RT_FLAG_RS_PRERESUMED 0
208	#define RT_FLAG_RS_RESUMED 1
209	#define RT_FLAG_RS_BITMAP_LOADED 2
210	#define RT_FLAG_UPDATE_SBS 3
211	#define RT_FLAG_RESHAPE_RS 4
212	#define RT_FLAG_RS_SUSPENDED 5
213	#define RT_FLAG_RS_IN_SYNC 6
214	#define RT_FLAG_RS_RESYNCING 7
215	#define RT_FLAG_RS_GROW 8
216	#define RT_FLAG_RS_FROZEN 9
217
218	/* Array elements of 64 bit needed for rebuild/failed disk bits */
219	#define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
220
221	/*
222	* raid set level, layout and chunk sectors backup/restore
223	*/
224	struct rs_layout {
225	int new_level;
226	int new_layout;
227	int new_chunk_sectors;
228	};
229
230	struct 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
261	static 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
270	static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)
271	{
272	struct mddev *mddev = &rs->md;
273
274	mddev->new_level = l->new_level;
275	mddev->new_layout = l->new_layout;
276	mddev->new_chunk_sectors = l->new_chunk_sectors;
277	}
278
279	/* raid10 algorithms (i.e. formats) */
280	#define ALGORITHM_RAID10_DEFAULT 0
281	#define ALGORITHM_RAID10_NEAR 1
282	#define ALGORITHM_RAID10_OFFSET 2
283	#define ALGORITHM_RAID10_FAR 3
284
285	/* Supported raid types and properties. */
286	static 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] */
317	static 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 */
323	static 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 */
347	static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
348	{
349	if (hweight32(flag) == 1) {
350	struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
351
352	while (anf-- > __arg_name_flags)
353	if (flag & anf->flag)
354	return anf->name;
355
356	} else
357	DMERR("%s called with more than one flag!", __func__);
358
359	return NULL;
360	}
361
362	/* Define correlation of raid456 journal cache modes and dm-raid target line parameters */
363	static 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 */
372	static 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(s1: mode, s2: _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 */
384	static const char *md_journal_mode_to_dm_raid(const int mode)
385	{
386	int m = ARRAY_SIZE(_raid456_journal_mode);
387
388	while (m--)
389	if (mode == _raid456_journal_mode[m].mode)
390	return _raid456_journal_mode[m].param;
391
392	return "unknown";
393	}
394
395	/*
396	* Bool helpers to test for various raid levels of a raid set.
397	* It's level as reported by the superblock rather than
398	* the requested raid_type passed to the constructor.
399	*/
400	/* Return true, if raid set in @rs is raid0 */
401	static 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 */
407	static 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 */
413	static 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 */
419	static 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 */
425	static bool rs_is_raid456(struct raid_set *rs)
426	{
427	return __within_range(v: rs->md.level, min: 4, max: 6);
428	}
429
430	/* Return true, if raid set in @rs is reshapable */
431	static bool __is_raid10_far(int layout);
432	static bool rs_is_reshapable(struct raid_set *rs)
433	{
434	return rs_is_raid456(rs) ||
435	(rs_is_raid10(rs) && !__is_raid10_far(layout: rs->md.new_layout));
436	}
437
438	/* Return true, if raid set in @rs is recovering */
439	static 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 */
445	static bool rs_is_reshaping(struct raid_set *rs)
446	{
447	return rs->md.reshape_position != MaxSector;
448	}
449
450	/*
451	* bool helpers to test for various raid levels of a raid type @rt
452	*/
453
454	/* Return true, if raid type in @rt is raid0 */
455	static 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 */
461	static 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 */
467	static 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 */
473	static bool rt_is_raid45(struct raid_type *rt)
474	{
475	return __within_range(v: rt->level, min: 4, max: 5);
476	}
477
478	/* Return true, if raid type in @rt is raid6 */
479	static 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 */
485	static bool rt_is_raid456(struct raid_type *rt)
486	{
487	return __within_range(v: rt->level, min: 4, max: 6);
488	}
489	/* END: raid level bools */
490
491	/* Return valid ctr flags for the raid level of @rs */
492	static unsigned long __valid_flags(struct raid_set *rs)
493	{
494	if (rt_is_raid0(rt: rs->raid_type))
495	return RAID0_VALID_FLAGS;
496	else if (rt_is_raid1(rt: rs->raid_type))
497	return RAID1_VALID_FLAGS;
498	else if (rt_is_raid10(rt: rs->raid_type))
499	return RAID10_VALID_FLAGS;
500	else if (rt_is_raid45(rt: rs->raid_type))
501	return RAID45_VALID_FLAGS;
502	else if (rt_is_raid6(rt: rs->raid_type))
503	return RAID6_VALID_FLAGS;
504
505	return 0;
506	}
507
508	/*
509	* Check for valid flags set on @rs
510	*
511	* Has to be called after parsing of the ctr flags!
512	*/
513	static 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 */
530	static unsigned int __raid10_near_copies(int layout)
531	{
532	return layout & 0xFF;
533	}
534
535	/* Return md raid10 far copies for @layout */
536	static unsigned int __raid10_far_copies(int layout)
537	{
538	return __raid10_near_copies(layout: layout >> RAID10_FAR_COPIES_SHIFT);
539	}
540
541	/* Return true if md raid10 offset for @layout */
542	static bool __is_raid10_offset(int layout)
543	{
544	return !!(layout & RAID10_OFFSET);
545	}
546
547	/* Return true if md raid10 near for @layout */
548	static 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 */
554	static 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 */
560	static const char *raid10_md_layout_to_format(int layout)
561	{
562	/*
563	* Bit 16 stands for "offset"
564	* (i.e. adjacent stripes hold copies)
565	*
566	* Refer to MD's raid10.c for details
567	*/
568	if (__is_raid10_offset(layout))
569	return "offset";
570
571	if (__raid10_near_copies(layout) > 1)
572	return "near";
573
574	if (__raid10_far_copies(layout) > 1)
575	return "far";
576
577	return "unknown";
578	}
579
580	/* Return md raid10 algorithm for @name */
581	static int raid10_name_to_format(const char *name)
582	{
583	if (!strcasecmp(s1: name, s2: "near"))
584	return ALGORITHM_RAID10_NEAR;
585	else if (!strcasecmp(s1: name, s2: "offset"))
586	return ALGORITHM_RAID10_OFFSET;
587	else if (!strcasecmp(s1: name, s2: "far"))
588	return ALGORITHM_RAID10_FAR;
589
590	return -EINVAL;
591	}
592
593	/* Return md raid10 copies for @layout */
594	static 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 */
600	static int raid10_format_to_md_layout(struct raid_set *rs,
601	unsigned int algorithm,
602	unsigned int copies)
603	{
604	unsigned int n = 1, f = 1, r = 0;
605
606	/*
607	* MD resilienece flaw:
608	*
609	* enabling use_far_sets for far/offset formats causes copies
610	* to be colocated on the same devs together with their origins!
611	*
612	* -> disable it for now in the definition above
613	*/
614	if (algorithm == ALGORITHM_RAID10_DEFAULT ||
615	algorithm == ALGORITHM_RAID10_NEAR)
616	n = copies;
617
618	else if (algorithm == ALGORITHM_RAID10_OFFSET) {
619	f = copies;
620	r = RAID10_OFFSET;
621	if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
622	r |= RAID10_USE_FAR_SETS;
623
624	} else if (algorithm == ALGORITHM_RAID10_FAR) {
625	f = copies;
626	if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
627	r |= RAID10_USE_FAR_SETS;
628
629	} else
630	return -EINVAL;
631
632	return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
633	}
634	/* END: MD raid10 bit definitions and helpers */
635
636	/* Check for any of the raid10 algorithms */
637	static 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 */
657	static 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(s1: rtp->name, s2: name))
663	return rtp;
664
665	return NULL;
666	}
667
668	/* Return raid_type for @name based derived from @level and @layout */
669	static 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 */
684	static void rs_set_rdev_sectors(struct raid_set *rs)
685	{
686	struct mddev *mddev = &rs->md;
687	struct md_rdev *rdev;
688
689	/*
690	* raid10 sets rdev->sector to the device size, which
691	* is unintended in case of out-of-place reshaping
692	*/
693	rdev_for_each(rdev, mddev)
694	if (!test_bit(Journal, &rdev->flags))
695	rdev->sectors = mddev->dev_sectors;
696	}
697
698	/*
699	* Change bdev capacity of @rs in case of a disk add/remove reshape
700	*/
701	static void rs_set_capacity(struct raid_set *rs)
702	{
703	struct gendisk *gendisk = dm_disk(md: dm_table_get_md(t: rs->ti->table));
704
705	set_capacity_and_notify(disk: gendisk, size: rs->md.array_sectors);
706	}
707
708	/*
709	* Set the mddev properties in @rs to the current
710	* ones retrieved from the freshest superblock
711	*/
712	static void rs_set_cur(struct raid_set *rs)
713	{
714	struct mddev *mddev = &rs->md;
715
716	mddev->new_level = mddev->level;
717	mddev->new_layout = mddev->layout;
718	mddev->new_chunk_sectors = mddev->chunk_sectors;
719	}
720
721	/*
722	* Set the mddev properties in @rs to the new
723	* ones requested by the ctr
724	*/
725	static 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
736	static 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(error: -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(error: -ENOMEM);
751	}
752
753	if (mddev_init(mddev: &rs->md)) {
754	kfree(objp: rs);
755	ti->error = "Cannot initialize raid context";
756	return ERR_PTR(error: -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(rdev: &rs->dev[i].rdev);
775
776	/*
777	* Remaining items to be initialized by further RAID params:
778	* rs->md.persistent
779	* rs->md.external
780	* rs->md.chunk_sectors
781	* rs->md.new_chunk_sectors
782	* rs->md.dev_sectors
783	*/
784
785	return rs;
786	}
787
788	/* Free all @rs allocations */
789	static void raid_set_free(struct raid_set *rs)
790	{
791	int i;
792
793	if (rs->journal_dev.dev) {
794	md_rdev_clear(rdev: &rs->journal_dev.rdev);
795	dm_put_device(ti: rs->ti, d: 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(ti: rs->ti, d: rs->dev[i].meta_dev);
801	md_rdev_clear(rdev: &rs->dev[i].rdev);
802	if (rs->dev[i].data_dev)
803	dm_put_device(ti: rs->ti, d: rs->dev[i].data_dev);
804	}
805
806	mddev_destroy(mddev: &rs->md);
807	kfree(objp: rs);
808	}
809
810	/*
811	* For every device we have two words
812	* <meta_dev>: meta device name or '-' if missing
813	* <data_dev>: data device name or '-' if missing
814	*
815	* The following are permitted:
816	* - -
817	* - <data_dev>
818	* <meta_dev> <data_dev>
819	*
820	* The following is not allowed:
821	* <meta_dev> -
822	*
823	* This code parses those words. If there is a failure,
824	* the caller must use raid_set_free() to unwind the operations.
825	*/
826	static 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(ti: rs->ti, path: arg, mode: dm_table_get_mode(t: rs->ti->table),
859	result: &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(ti: rs->ti, path: arg, mode: dm_table_get_mode(t: rs->ti->table),
892	result: &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(new: &rs->dev[i].rdev.same_set, head: &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(new: &rs->journal_dev.rdev.same_set, head: &rs->md.disks);
910
911	if (metadata_available) {
912	rs->md.external = 0;
913	rs->md.persistent = 1;
914	rs->md.major_version = 2;
915	} else if (rebuild && !rs->md.recovery_cp) {
916	/*
917	* Without metadata, we will not be able to tell if the array
918	* is in-sync or not - we must assume it is not. Therefore,
919	* it is impossible to rebuild a drive.
920	*
921	* Even if there is metadata, the on-disk information may
922	* indicate that the array is not in-sync and it will then
923	* fail at that time.
924	*
925	* User could specify 'nosync' option if desperate.
926	*/
927	rs->ti->error = "Unable to rebuild drive while array is not in-sync";
928	return -EINVAL;
929	}
930
931	return 0;
932	}
933
934	/*
935	* validate_region_size
936	* @rs
937	* @region_size: region size in sectors. If 0, pick a size (4MiB default).
938	*
939	* Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
940	* Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
941	*
942	* Returns: 0 on success, -EINVAL on failure.
943	*/
944	static 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(n: 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(n: region_size);
995
996	return 0;
997	}
998
999	/*
1000	* validate_raid_redundancy
1001	* @rs
1002	*
1003	* Determine if there are enough devices in the array that haven't
1004	* failed (or are being rebuilt) to form a usable array.
1005	*
1006	* Returns: 0 on success, -EINVAL on failure.
1007	*/
1008	static 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(layout: rs->md.new_layout);
1035	if (copies < 2) {
1036	DMERR("Bogus raid10 data copies < 2!");
1037	return -EINVAL;
1038	}
1039
1040	if (rebuild_cnt < copies)
1041	break;
1042
1043	/*
1044	* It is possible to have a higher rebuild count for RAID10,
1045	* as long as the failed devices occur in different mirror
1046	* groups (i.e. different stripes).
1047	*
1048	* When checking "near" format, make sure no adjacent devices
1049	* have failed beyond what can be handled. In addition to the
1050	* simple case where the number of devices is a multiple of the
1051	* number of copies, we must also handle cases where the number
1052	* of devices is not a multiple of the number of copies.
1053	* E.g. dev1 dev2 dev3 dev4 dev5
1054	* A A B B C
1055	* C D D E E
1056	*/
1057	raid_disks = min(rs->raid_disks, rs->md.raid_disks);
1058	if (__is_raid10_near(layout: rs->md.new_layout)) {
1059	for (i = 0; i < raid_disks; i++) {
1060	if (!(i % copies))
1061	rebuilds_per_group = 0;
1062	if ((!rs->dev[i].rdev.sb_page ||
1063	!test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1064	(++rebuilds_per_group >= copies))
1065	goto too_many;
1066	}
1067	break;
1068	}
1069
1070	/*
1071	* When checking "far" and "offset" formats, we need to ensure
1072	* that the device that holds its copy is not also dead or
1073	* being rebuilt. (Note that "far" and "offset" formats only
1074	* support two copies right now. These formats also only ever
1075	* use the 'use_far_sets' variant.)
1076	*
1077	* This check is somewhat complicated by the need to account
1078	* for arrays that are not a multiple of (far) copies. This
1079	* results in the need to treat the last (potentially larger)
1080	* set differently.
1081	*/
1082	group_size = (raid_disks / copies);
1083	last_group_start = (raid_disks / group_size) - 1;
1084	last_group_start *= group_size;
1085	for (i = 0; i < raid_disks; i++) {
1086	if (!(i % copies) && !(i > last_group_start))
1087	rebuilds_per_group = 0;
1088	if ((!rs->dev[i].rdev.sb_page ||
1089	!test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1090	(++rebuilds_per_group >= copies))
1091	goto too_many;
1092	}
1093	break;
1094	default:
1095	if (rebuild_cnt)
1096	return -EINVAL;
1097	}
1098
1099	return 0;
1100
1101	too_many:
1102	return -EINVAL;
1103	}
1104
1105	/*
1106	* Possible arguments are...
1107	* <chunk_size> [optional_args]
1108	*
1109	* Argument definitions
1110	* <chunk_size> The number of sectors per disk that
1111	* will form the "stripe"
1112	* [[no]sync] Force or prevent recovery of the
1113	* entire array
1114	* [rebuild <idx>] Rebuild the drive indicated by the index
1115	* [daemon_sleep <ms>] Time between bitmap daemon work to
1116	* clear bits
1117	* [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1118	* [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1119	* [write_mostly <idx>] Indicate a write mostly drive via index
1120	* [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
1121	* [stripe_cache <sectors>] Stripe cache size for higher RAIDs
1122	* [region_size <sectors>] Defines granularity of bitmap
1123	* [journal_dev <dev>] raid4/5/6 journaling deviice
1124	* (i.e. write hole closing log)
1125	*
1126	* RAID10-only options:
1127	* [raid10_copies <# copies>] Number of copies. (Default: 2)
1128	* [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
1129	*/
1130	static 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(s: arg, base: 10, res: &value) < 0) {
1146	rs->ti->error = "Bad numerical argument given for chunk_size";
1147	return -EINVAL;
1148	}
1149
1150	/*
1151	* First, parse the in-order required arguments
1152	* "chunk_size" is the only argument of this type.
1153	*/
1154	if (rt_is_raid1(rt)) {
1155	if (value)
1156	DMERR("Ignoring chunk size parameter for RAID 1");
1157	value = 0;
1158	} else if (!is_power_of_2(n: value)) {
1159	rs->ti->error = "Chunk size must be a power of 2";
1160	return -EINVAL;
1161	} else if (value < 8) {
1162	rs->ti->error = "Chunk size value is too small";
1163	return -EINVAL;
1164	}
1165
1166	rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1167
1168	/*
1169	* We set each individual device as In_sync with a completed
1170	* 'recovery_offset'. If there has been a device failure or
1171	* replacement then one of the following cases applies:
1172	*
1173	* 1) User specifies 'rebuild'.
1174	* - Device is reset when param is read.
1175	* 2) A new device is supplied.
1176	* - No matching superblock found, resets device.
1177	* 3) Device failure was transient and returns on reload.
1178	* - Failure noticed, resets device for bitmap replay.
1179	* 4) Device hadn't completed recovery after previous failure.
1180	* - Superblock is read and overrides recovery_offset.
1181	*
1182	* What is found in the superblocks of the devices is always
1183	* authoritative, unless 'rebuild' or '[no]sync' was specified.
1184	*/
1185	for (i = 0; i < rs->raid_disks; i++) {
1186	set_bit(nr: In_sync, addr: &rs->dev[i].rdev.flags);
1187	rs->dev[i].rdev.recovery_offset = MaxSector;
1188	}
1189
1190	/*
1191	* Second, parse the unordered optional arguments
1192	*/
1193	for (i = 0; i < num_raid_params; i++) {
1194	key = dm_shift_arg(as);
1195	if (!key) {
1196	rs->ti->error = "Not enough raid parameters given";
1197	return -EINVAL;
1198	}
1199
1200	if (!strcasecmp(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1201	if (test_and_set_bit(__CTR_FLAG_NOSYNC, addr: &rs->ctr_flags)) {
1202	rs->ti->error = "Only one 'nosync' argument allowed";
1203	return -EINVAL;
1204	}
1205	continue;
1206	}
1207	if (!strcasecmp(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1208	if (test_and_set_bit(__CTR_FLAG_SYNC, addr: &rs->ctr_flags)) {
1209	rs->ti->error = "Only one 'sync' argument allowed";
1210	return -EINVAL;
1211	}
1212	continue;
1213	}
1214	if (!strcasecmp(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1215	if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, addr: &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(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1234	if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, addr: &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(name: 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(s1: key, s2: 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, addr: &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(ti: rs->ti, path: arg, mode: dm_table_get_mode(t: rs->ti->table),
1264	result: &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(rdev: jdev);
1271	jdev->mddev = &rs->md;
1272	jdev->bdev = rs->journal_dev.dev->bdev;
1273	jdev->sectors = bdev_nr_sectors(bdev: 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(nr: Journal, addr: &jdev->flags);
1280	continue;
1281	}
1282
1283	/* "journal_mode <mode>" ("journal_dev" mandatory!) */
1284	if (!strcasecmp(s1: key, s2: 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, addr: &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(mode: 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(s: arg, base: 10, res: &value) < 0) {
1308	rs->ti->error = "Bad numerical argument given in raid params";
1309	return -EINVAL;
1310	}
1311
1312	if (!strcasecmp(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1313	/*
1314	* "rebuild" is being passed in by userspace to provide
1315	* indexes of replaced devices and to set up additional
1316	* devices on raid level takeover.
1317	*/
1318	if (!__within_range(v: value, min: 0, max: rs->raid_disks - 1)) {
1319	rs->ti->error = "Invalid rebuild index given";
1320	return -EINVAL;
1321	}
1322
1323	if (test_and_set_bit(nr: value, addr: (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(nr: In_sync, addr: &rd->rdev.flags);
1330	clear_bit(nr: Faulty, addr: &rd->rdev.flags);
1331	rd->rdev.recovery_offset = 0;
1332	set_bit(__CTR_FLAG_REBUILD, addr: &rs->ctr_flags);
1333	} else if (!strcasecmp(s1: key, s2: 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(v: value, min: 0, max: 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(nr: WriteMostly, addr: &rs->dev[value].rdev.flags);
1346	set_bit(__CTR_FLAG_WRITE_MOSTLY, addr: &rs->ctr_flags);
1347	} else if (!strcasecmp(s1: key, s2: 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, addr: &rs->ctr_flags)) {
1354	rs->ti->error = "Only one max_write_behind argument pair allowed";
1355	return -EINVAL;
1356	}
1357
1358	/*
1359	* In device-mapper, we specify things in sectors, but
1360	* MD records this value in kB
1361	*/
1362	if (value < 0 || value / 2 > COUNTER_MAX) {
1363	rs->ti->error = "Max write-behind limit out of range";
1364	return -EINVAL;
1365	}
1366
1367	rs->md.bitmap_info.max_write_behind = value / 2;
1368	} else if (!strcasecmp(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1369	if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, addr: &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(s1: key, s2: 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, addr: &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(s1: key, s2: 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, addr: &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), min: 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(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1405	if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, addr: &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(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1421	if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, addr: &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(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1432	if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, addr: &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(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1443	if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, addr: &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(s1: key, s2: dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1451	if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, addr: &rs->ctr_flags)) {
1452	rs->ti->error = "Only one raid10_copies argument pair allowed";
1453	return -EINVAL;
1454	}
1455
1456	if (!__within_range(v: value, min: 2, max: rs->md.raid_disks)) {
1457	rs->ti->error = "Bad value for 'raid10_copies'";
1458	return -EINVAL;
1459	}
1460
1461	raid10_copies = value;
1462	} else {
1463	DMERR("Unable to parse RAID parameter: %s", key);
1464	rs->ti->error = "Unable to parse RAID parameter";
1465	return -EINVAL;
1466	}
1467	}
1468
1469	if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1470	test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1471	rs->ti->error = "sync and nosync are mutually exclusive";
1472	return -EINVAL;
1473	}
1474
1475	if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
1476	(test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
1477	test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
1478	rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
1479	return -EINVAL;
1480	}
1481
1482	if (write_mostly >= rs->md.raid_disks) {
1483	rs->ti->error = "Can't set all raid1 devices to write_mostly";
1484	return -EINVAL;
1485	}
1486
1487	if (rs->md.sync_speed_max &&
1488	rs->md.sync_speed_min > rs->md.sync_speed_max) {
1489	rs->ti->error = "Bogus recovery rates";
1490	return -EINVAL;
1491	}
1492
1493	if (validate_region_size(rs, region_size))
1494	return -EINVAL;
1495
1496	if (rs->md.chunk_sectors)
1497	max_io_len = rs->md.chunk_sectors;
1498	else
1499	max_io_len = region_size;
1500
1501	if (dm_set_target_max_io_len(ti: rs->ti, len: 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, algorithm: raid10_format, copies: 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(level: 10, layout: 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 */
1541	static 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(rt: 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, size: 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) */
1581	static 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) */
1587	static unsigned int rs_data_stripes(struct raid_set *rs)
1588	{
1589	return rs->raid_disks - rs->raid_type->parity_devs;
1590	}
1591
1592	/*
1593	* Retrieve rdev->sectors from any valid raid device of @rs
1594	* to allow userpace to pass in arbitray "- -" device tupples.
1595	*/
1596	static 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. */
1612	static 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	/* Calculate the sectors per device and per array used for @rs */
1630	static int rs_set_dev_and_array_sectors(struct raid_set *rs, sector_t sectors, bool use_mddev)
1631	{
1632	int delta_disks;
1633	unsigned int data_stripes;
1634	sector_t array_sectors = sectors, dev_sectors = sectors;
1635	struct mddev *mddev = &rs->md;
1636
1637	if (use_mddev) {
1638	delta_disks = mddev->delta_disks;
1639	data_stripes = mddev_data_stripes(rs);
1640	} else {
1641	delta_disks = rs->delta_disks;
1642	data_stripes = rs_data_stripes(rs);
1643	}
1644
1645	/* Special raid1 case w/o delta_disks support (yet) */
1646	if (rt_is_raid1(rt: rs->raid_type))
1647	;
1648	else if (rt_is_raid10(rt: rs->raid_type)) {
1649	if (rs->raid10_copies < 2 ||
1650	delta_disks < 0) {
1651	rs->ti->error = "Bogus raid10 data copies or delta disks";
1652	return -EINVAL;
1653	}
1654
1655	dev_sectors *= rs->raid10_copies;
1656	if (sector_div(dev_sectors, data_stripes))
1657	goto bad;
1658
1659	array_sectors = (data_stripes + delta_disks) * dev_sectors;
1660	if (sector_div(array_sectors, rs->raid10_copies))
1661	goto bad;
1662
1663	} else if (sector_div(dev_sectors, data_stripes))
1664	goto bad;
1665
1666	else
1667	/* Striped layouts */
1668	array_sectors = (data_stripes + delta_disks) * dev_sectors;
1669
1670	mddev->array_sectors = array_sectors;
1671	mddev->dev_sectors = dev_sectors;
1672	rs_set_rdev_sectors(rs);
1673
1674	return _check_data_dev_sectors(rs);
1675	bad:
1676	rs->ti->error = "Target length not divisible by number of data devices";
1677	return -EINVAL;
1678	}
1679
1680	/* Setup recovery on @rs */
1681	static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1682	{
1683	/* raid0 does not recover */
1684	if (rs_is_raid0(rs))
1685	rs->md.recovery_cp = MaxSector;
1686	/*
1687	* A raid6 set has to be recovered either
1688	* completely or for the grown part to
1689	* ensure proper parity and Q-Syndrome
1690	*/
1691	else if (rs_is_raid6(rs))
1692	rs->md.recovery_cp = dev_sectors;
1693	/*
1694	* Other raid set types may skip recovery
1695	* depending on the 'nosync' flag.
1696	*/
1697	else
1698	rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
1699	? MaxSector : dev_sectors;
1700	}
1701
1702	static void do_table_event(struct work_struct *ws)
1703	{
1704	struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1705
1706	smp_rmb(); /* Make sure we access most actual mddev properties */
1707	if (!rs_is_reshaping(rs)) {
1708	if (rs_is_raid10(rs))
1709	rs_set_rdev_sectors(rs);
1710	rs_set_capacity(rs);
1711	}
1712	dm_table_event(t: rs->ti->table);
1713	}
1714
1715	/*
1716	* Make sure a valid takover (level switch) is being requested on @rs
1717	*
1718	* Conversions of raid sets from one MD personality to another
1719	* have to conform to restrictions which are enforced here.
1720	*/
1721	static int rs_check_takeover(struct raid_set *rs)
1722	{
1723	struct mddev *mddev = &rs->md;
1724	unsigned int near_copies;
1725
1726	if (rs->md.degraded) {
1727	rs->ti->error = "Can't takeover degraded raid set";
1728	return -EPERM;
1729	}
1730
1731	if (rs_is_reshaping(rs)) {
1732	rs->ti->error = "Can't takeover reshaping raid set";
1733	return -EPERM;
1734	}
1735
1736	switch (mddev->level) {
1737	case 0:
1738	/* raid0 -> raid1/5 with one disk */
1739	if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1740	mddev->raid_disks == 1)
1741	return 0;
1742
1743	/* raid0 -> raid10 */
1744	if (mddev->new_level == 10 &&
1745	!(rs->raid_disks % mddev->raid_disks))
1746	return 0;
1747
1748	/* raid0 with multiple disks -> raid4/5/6 */
1749	if (__within_range(v: mddev->new_level, min: 4, max: 6) &&
1750	mddev->new_layout == ALGORITHM_PARITY_N &&
1751	mddev->raid_disks > 1)
1752	return 0;
1753
1754	break;
1755
1756	case 10:
1757	/* Can't takeover raid10_offset! */
1758	if (__is_raid10_offset(layout: mddev->layout))
1759	break;
1760
1761	near_copies = __raid10_near_copies(layout: mddev->layout);
1762
1763	/* raid10* -> raid0 */
1764	if (mddev->new_level == 0) {
1765	/* Can takeover raid10_near with raid disks divisable by data copies! */
1766	if (near_copies > 1 &&
1767	!(mddev->raid_disks % near_copies)) {
1768	mddev->raid_disks /= near_copies;
1769	mddev->delta_disks = mddev->raid_disks;
1770	return 0;
1771	}
1772
1773	/* Can takeover raid10_far */
1774	if (near_copies == 1 &&
1775	__raid10_far_copies(layout: mddev->layout) > 1)
1776	return 0;
1777
1778	break;
1779	}
1780
1781	/* raid10_{near,far} -> raid1 */
1782	if (mddev->new_level == 1 &&
1783	max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1784	return 0;
1785
1786	/* raid10_{near,far} with 2 disks -> raid4/5 */
1787	if (__within_range(v: mddev->new_level, min: 4, max: 5) &&
1788	mddev->raid_disks == 2)
1789	return 0;
1790	break;
1791
1792	case 1:
1793	/* raid1 with 2 disks -> raid4/5 */
1794	if (__within_range(v: mddev->new_level, min: 4, max: 5) &&
1795	mddev->raid_disks == 2) {
1796	mddev->degraded = 1;
1797	return 0;
1798	}
1799
1800	/* raid1 -> raid0 */
1801	if (mddev->new_level == 0 &&
1802	mddev->raid_disks == 1)
1803	return 0;
1804
1805	/* raid1 -> raid10 */
1806	if (mddev->new_level == 10)
1807	return 0;
1808	break;
1809
1810	case 4:
1811	/* raid4 -> raid0 */
1812	if (mddev->new_level == 0)
1813	return 0;
1814
1815	/* raid4 -> raid1/5 with 2 disks */
1816	if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1817	mddev->raid_disks == 2)
1818	return 0;
1819
1820	/* raid4 -> raid5/6 with parity N */
1821	if (__within_range(v: mddev->new_level, min: 5, max: 6) &&
1822	mddev->layout == ALGORITHM_PARITY_N)
1823	return 0;
1824	break;
1825
1826	case 5:
1827	/* raid5 with parity N -> raid0 */
1828	if (mddev->new_level == 0 &&
1829	mddev->layout == ALGORITHM_PARITY_N)
1830	return 0;
1831
1832	/* raid5 with parity N -> raid4 */
1833	if (mddev->new_level == 4 &&
1834	mddev->layout == ALGORITHM_PARITY_N)
1835	return 0;
1836
1837	/* raid5 with 2 disks -> raid1/4/10 */
1838	if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1839	mddev->raid_disks == 2)
1840	return 0;
1841
1842	/* raid5_* -> raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
1843	if (mddev->new_level == 6 &&
1844	((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1845	__within_range(v: mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1846	return 0;
1847	break;
1848
1849	case 6:
1850	/* raid6 with parity N -> raid0 */
1851	if (mddev->new_level == 0 &&
1852	mddev->layout == ALGORITHM_PARITY_N)
1853	return 0;
1854
1855	/* raid6 with parity N -> raid4 */
1856	if (mddev->new_level == 4 &&
1857	mddev->layout == ALGORITHM_PARITY_N)
1858	return 0;
1859
1860	/* raid6_*_n with Q-Syndrome N -> raid5_* */
1861	if (mddev->new_level == 5 &&
1862	((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1863	__within_range(v: mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1864	return 0;
1865	break;
1866
1867	default:
1868	break;
1869	}
1870
1871	rs->ti->error = "takeover not possible";
1872	return -EINVAL;
1873	}
1874
1875	/* True if @rs requested to be taken over */
1876	static bool rs_takeover_requested(struct raid_set *rs)
1877	{
1878	return rs->md.new_level != rs->md.level;
1879	}
1880
1881	/* True if layout is set to reshape. */
1882	static bool rs_is_layout_change(struct raid_set *rs, bool use_mddev)
1883	{
1884	return (use_mddev ? rs->md.delta_disks : rs->delta_disks) ||
1885	rs->md.new_layout != rs->md.layout ||
1886	rs->md.new_chunk_sectors != rs->md.chunk_sectors;
1887	}
1888
1889	/* True if @rs is requested to reshape by ctr */
1890	static bool rs_reshape_requested(struct raid_set *rs)
1891	{
1892	bool change;
1893	struct mddev *mddev = &rs->md;
1894
1895	if (rs_takeover_requested(rs))
1896	return false;
1897
1898	if (rs_is_raid0(rs))
1899	return false;
1900
1901	change = rs_is_layout_change(rs, use_mddev: false);
1902
1903	/* Historical case to support raid1 reshape without delta disks */
1904	if (rs_is_raid1(rs)) {
1905	if (rs->delta_disks)
1906	return !!rs->delta_disks;
1907
1908	return !change &&
1909	mddev->raid_disks != rs->raid_disks;
1910	}
1911
1912	if (rs_is_raid10(rs))
1913	return change &&
1914	!__is_raid10_far(layout: mddev->new_layout) &&
1915	rs->delta_disks >= 0;
1916
1917	return change;
1918	}
1919
1920	/* Features */
1921	#define FEATURE_FLAG_SUPPORTS_V190 0x1 /* Supports extended superblock */
1922
1923	/* State flags for sb->flags */
1924	#define SB_FLAG_RESHAPE_ACTIVE 0x1
1925	#define SB_FLAG_RESHAPE_BACKWARDS 0x2
1926
1927	/*
1928	* This structure is never routinely used by userspace, unlike md superblocks.
1929	* Devices with this superblock should only ever be accessed via device-mapper.
1930	*/
1931	#define DM_RAID_MAGIC 0x64526D44
1932	struct dm_raid_superblock {
1933	__le32 magic; /* "DmRd" */
1934	__le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1935
1936	__le32 num_devices; /* Number of devices in this raid set. (Max 64) */
1937	__le32 array_position; /* The position of this drive in the raid set */
1938
1939	__le64 events; /* Incremented by md when superblock updated */
1940	__le64 failed_devices; /* Pre 1.9.0 part of bit field of devices to */
1941	/* indicate failures (see extension below) */
1942
1943	/*
1944	* This offset tracks the progress of the repair or replacement of
1945	* an individual drive.
1946	*/
1947	__le64 disk_recovery_offset;
1948
1949	/*
1950	* This offset tracks the progress of the initial raid set
1951	* synchronisation/parity calculation.
1952	*/
1953	__le64 array_resync_offset;
1954
1955	/*
1956	* raid characteristics
1957	*/
1958	__le32 level;
1959	__le32 layout;
1960	__le32 stripe_sectors;
1961
1962	/********************************************************************
1963	* BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1964	*
1965	* FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
1966	*/
1967
1968	__le32 flags; /* Flags defining array states for reshaping */
1969
1970	/*
1971	* This offset tracks the progress of a raid
1972	* set reshape in order to be able to restart it
1973	*/
1974	__le64 reshape_position;
1975
1976	/*
1977	* These define the properties of the array in case of an interrupted reshape
1978	*/
1979	__le32 new_level;
1980	__le32 new_layout;
1981	__le32 new_stripe_sectors;
1982	__le32 delta_disks;
1983
1984	__le64 array_sectors; /* Array size in sectors */
1985
1986	/*
1987	* Sector offsets to data on devices (reshaping).
1988	* Needed to support out of place reshaping, thus
1989	* not writing over any stripes whilst converting
1990	* them from old to new layout
1991	*/
1992	__le64 data_offset;
1993	__le64 new_data_offset;
1994
1995	__le64 sectors; /* Used device size in sectors */
1996
1997	/*
1998	* Additional Bit field of devices indicating failures to support
1999	* up to 256 devices with the 1.9.0 on-disk metadata format
2000	*/
2001	__le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
2002
2003	__le32 incompat_features; /* Used to indicate any incompatible features */
2004
2005	/* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
2006	} __packed;
2007
2008	/*
2009	* Check for reshape constraints on raid set @rs:
2010	*
2011	* - reshape function non-existent
2012	* - degraded set
2013	* - ongoing recovery
2014	* - ongoing reshape
2015	*
2016	* Returns 0 if none or -EPERM if given constraint
2017	* and error message reference in @errmsg
2018	*/
2019	static int rs_check_reshape(struct raid_set *rs)
2020	{
2021	struct mddev *mddev = &rs->md;
2022
2023	if (!mddev->pers || !mddev->pers->check_reshape)
2024	rs->ti->error = "Reshape not supported";
2025	else if (mddev->degraded)
2026	rs->ti->error = "Can't reshape degraded raid set";
2027	else if (rs_is_recovering(rs))
2028	rs->ti->error = "Convert request on recovering raid set prohibited";
2029	else if (rs_is_reshaping(rs))
2030	rs->ti->error = "raid set already reshaping!";
2031	else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
2032	rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
2033	else
2034	return 0;
2035
2036	return -EPERM;
2037	}
2038
2039	static int read_disk_sb(struct md_rdev *rdev, int size, bool force_reload)
2040	{
2041	BUG_ON(!rdev->sb_page);
2042
2043	if (rdev->sb_loaded && !force_reload)
2044	return 0;
2045
2046	rdev->sb_loaded = 0;
2047
2048	if (!sync_page_io(rdev, sector: 0, size, page: rdev->sb_page, opf: REQ_OP_READ, metadata_op: true)) {
2049	DMERR("Failed to read superblock of device at position %d",
2050	rdev->raid_disk);
2051	md_error(mddev: rdev->mddev, rdev);
2052	set_bit(nr: Faulty, addr: &rdev->flags);
2053	return -EIO;
2054	}
2055
2056	rdev->sb_loaded = 1;
2057
2058	return 0;
2059	}
2060
2061	static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2062	{
2063	failed_devices[0] = le64_to_cpu(sb->failed_devices);
2064	memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
2065
2066	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2067	int i = ARRAY_SIZE(sb->extended_failed_devices);
2068
2069	while (i--)
2070	failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
2071	}
2072	}
2073
2074	static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2075	{
2076	int i = ARRAY_SIZE(sb->extended_failed_devices);
2077
2078	sb->failed_devices = cpu_to_le64(failed_devices[0]);
2079	while (i--)
2080	sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
2081	}
2082
2083	/*
2084	* Synchronize the superblock members with the raid set properties
2085	*
2086	* All superblock data is little endian.
2087	*/
2088	static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
2089	{
2090	bool update_failed_devices = false;
2091	unsigned int i;
2092	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2093	struct dm_raid_superblock *sb;
2094	struct raid_set *rs = container_of(mddev, struct raid_set, md);
2095
2096	/* No metadata device, no superblock */
2097	if (!rdev->meta_bdev)
2098	return;
2099
2100	BUG_ON(!rdev->sb_page);
2101
2102	sb = page_address(rdev->sb_page);
2103
2104	sb_retrieve_failed_devices(sb, failed_devices);
2105
2106	for (i = 0; i < rs->raid_disks; i++)
2107	if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
2108	update_failed_devices = true;
2109	set_bit(nr: i, addr: (void *) failed_devices);
2110	}
2111
2112	if (update_failed_devices)
2113	sb_update_failed_devices(sb, failed_devices);
2114
2115	sb->magic = cpu_to_le32(DM_RAID_MAGIC);
2116	sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2117
2118	sb->num_devices = cpu_to_le32(mddev->raid_disks);
2119	sb->array_position = cpu_to_le32(rdev->raid_disk);
2120
2121	sb->events = cpu_to_le64(mddev->events);
2122
2123	sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
2124	sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
2125
2126	sb->level = cpu_to_le32(mddev->level);
2127	sb->layout = cpu_to_le32(mddev->layout);
2128	sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
2129
2130	/********************************************************************
2131	* BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
2132	*
2133	* FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
2134	*/
2135	sb->new_level = cpu_to_le32(mddev->new_level);
2136	sb->new_layout = cpu_to_le32(mddev->new_layout);
2137	sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
2138
2139	sb->delta_disks = cpu_to_le32(mddev->delta_disks);
2140
2141	smp_rmb(); /* Make sure we access most recent reshape position */
2142	sb->reshape_position = cpu_to_le64(mddev->reshape_position);
2143	if (le64_to_cpu(sb->reshape_position) != MaxSector) {
2144	/* Flag ongoing reshape */
2145	sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
2146
2147	if (mddev->delta_disks < 0 || mddev->reshape_backwards)
2148	sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
2149	} else {
2150	/* Clear reshape flags */
2151	sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
2152	}
2153
2154	sb->array_sectors = cpu_to_le64(mddev->array_sectors);
2155	sb->data_offset = cpu_to_le64(rdev->data_offset);
2156	sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
2157	sb->sectors = cpu_to_le64(rdev->sectors);
2158	sb->incompat_features = cpu_to_le32(0);
2159
2160	/* Zero out the rest of the payload after the size of the superblock */
2161	memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
2162	}
2163
2164	/*
2165	* super_load
2166	*
2167	* This function creates a superblock if one is not found on the device
2168	* and will decide which superblock to use if there's a choice.
2169	*
2170	* Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
2171	*/
2172	static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
2173	{
2174	int r;
2175	struct dm_raid_superblock *sb;
2176	struct dm_raid_superblock *refsb;
2177	uint64_t events_sb, events_refsb;
2178
2179	r = read_disk_sb(rdev, size: rdev->sb_size, force_reload: false);
2180	if (r)
2181	return r;
2182
2183	sb = page_address(rdev->sb_page);
2184
2185	/*
2186	* Two cases that we want to write new superblocks and rebuild:
2187	* 1) New device (no matching magic number)
2188	* 2) Device specified for rebuild (!In_sync w/ offset == 0)
2189	*/
2190	if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
2191	(!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
2192	super_sync(mddev: rdev->mddev, rdev);
2193
2194	set_bit(FirstUse, addr: &rdev->flags);
2195	sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2196
2197	/* Force writing of superblocks to disk */
2198	set_bit(nr: MD_SB_CHANGE_DEVS, addr: &rdev->mddev->sb_flags);
2199
2200	/* Any superblock is better than none, choose that if given */
2201	return refdev ? 0 : 1;
2202	}
2203
2204	if (!refdev)
2205	return 1;
2206
2207	events_sb = le64_to_cpu(sb->events);
2208
2209	refsb = page_address(refdev->sb_page);
2210	events_refsb = le64_to_cpu(refsb->events);
2211
2212	return (events_sb > events_refsb) ? 1 : 0;
2213	}
2214
2215	static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
2216	{
2217	int role;
2218	struct mddev *mddev = &rs->md;
2219	uint64_t events_sb;
2220	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2221	struct dm_raid_superblock *sb;
2222	uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
2223	struct md_rdev *r;
2224	struct dm_raid_superblock *sb2;
2225
2226	sb = page_address(rdev->sb_page);
2227	events_sb = le64_to_cpu(sb->events);
2228
2229	/*
2230	* Initialise to 1 if this is a new superblock.
2231	*/
2232	mddev->events = events_sb ? : 1;
2233
2234	mddev->reshape_position = MaxSector;
2235
2236	mddev->raid_disks = le32_to_cpu(sb->num_devices);
2237	mddev->level = le32_to_cpu(sb->level);
2238	mddev->layout = le32_to_cpu(sb->layout);
2239	mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
2240
2241	/*
2242	* Reshaping is supported, e.g. reshape_position is valid
2243	* in superblock and superblock content is authoritative.
2244	*/
2245	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2246	/* Superblock is authoritative wrt given raid set layout! */
2247	mddev->new_level = le32_to_cpu(sb->new_level);
2248	mddev->new_layout = le32_to_cpu(sb->new_layout);
2249	mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
2250	mddev->delta_disks = le32_to_cpu(sb->delta_disks);
2251	mddev->array_sectors = le64_to_cpu(sb->array_sectors);
2252
2253	/* raid was reshaping and got interrupted */
2254	if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2255	if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2256	DMERR("Reshape requested but raid set is still reshaping");
2257	return -EINVAL;
2258	}
2259
2260	if (mddev->delta_disks < 0 ||
2261	(!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2262	mddev->reshape_backwards = 1;
2263	else
2264	mddev->reshape_backwards = 0;
2265
2266	mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2267	rs->raid_type = get_raid_type_by_ll(level: mddev->level, layout: mddev->layout);
2268	}
2269
2270	} else {
2271	/*
2272	* No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2273	*/
2274	struct raid_type *rt_cur = get_raid_type_by_ll(level: mddev->level, layout: mddev->layout);
2275	struct raid_type *rt_new = get_raid_type_by_ll(level: mddev->new_level, layout: mddev->new_layout);
2276
2277	if (rs_takeover_requested(rs)) {
2278	if (rt_cur && rt_new)
2279	DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",
2280	rt_cur->name, rt_new->name);
2281	else
2282	DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");
2283	return -EINVAL;
2284	} else if (rs_reshape_requested(rs)) {
2285	DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");
2286	if (mddev->layout != mddev->new_layout) {
2287	if (rt_cur && rt_new)
2288	DMERR(" current layout %s vs new layout %s",
2289	rt_cur->name, rt_new->name);
2290	else
2291	DMERR(" current layout 0x%X vs new layout 0x%X",
2292	le32_to_cpu(sb->layout), mddev->new_layout);
2293	}
2294	if (mddev->chunk_sectors != mddev->new_chunk_sectors)
2295	DMERR(" current stripe sectors %u vs new stripe sectors %u",
2296	mddev->chunk_sectors, mddev->new_chunk_sectors);
2297	if (rs->delta_disks)
2298	DMERR(" current %u disks vs new %u disks",
2299	mddev->raid_disks, mddev->raid_disks + rs->delta_disks);
2300	if (rs_is_raid10(rs)) {
2301	DMERR(" Old layout: %s w/ %u copies",
2302	raid10_md_layout_to_format(mddev->layout),
2303	raid10_md_layout_to_copies(mddev->layout));
2304	DMERR(" New layout: %s w/ %u copies",
2305	raid10_md_layout_to_format(mddev->new_layout),
2306	raid10_md_layout_to_copies(mddev->new_layout));
2307	}
2308	return -EINVAL;
2309	}
2310
2311	DMINFO("Discovered old metadata format; upgrading to extended metadata format");
2312	}
2313
2314	if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2315	mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2316
2317	/*
2318	* During load, we set FirstUse if a new superblock was written.
2319	* There are two reasons we might not have a superblock:
2320	* 1) The raid set is brand new - in which case, all of the
2321	* devices must have their In_sync bit set. Also,
2322	* recovery_cp must be 0, unless forced.
2323	* 2) This is a new device being added to an old raid set
2324	* and the new device needs to be rebuilt - in which
2325	* case the In_sync bit will /not/ be set and
2326	* recovery_cp must be MaxSector.
2327	* 3) This is/are a new device(s) being added to an old
2328	* raid set during takeover to a higher raid level
2329	* to provide capacity for redundancy or during reshape
2330	* to add capacity to grow the raid set.
2331	*/
2332	rdev_for_each(r, mddev) {
2333	if (test_bit(Journal, &rdev->flags))
2334	continue;
2335
2336	if (test_bit(FirstUse, &r->flags))
2337	new_devs++;
2338
2339	if (!test_bit(In_sync, &r->flags)) {
2340	DMINFO("Device %d specified for rebuild; clearing superblock",
2341	r->raid_disk);
2342	rebuilds++;
2343
2344	if (test_bit(FirstUse, &r->flags))
2345	rebuild_and_new++;
2346	}
2347	}
2348
2349	if (new_devs == rs->raid_disks || !rebuilds) {
2350	/* Replace a broken device */
2351	if (new_devs == rs->raid_disks) {
2352	DMINFO("Superblocks created for new raid set");
2353	set_bit(nr: MD_ARRAY_FIRST_USE, addr: &mddev->flags);
2354	} else if (new_devs != rebuilds &&
2355	new_devs != rs->delta_disks) {
2356	DMERR("New device injected into existing raid set without "
2357	"'delta_disks' or 'rebuild' parameter specified");
2358	return -EINVAL;
2359	}
2360	} else if (new_devs && new_devs != rebuilds) {
2361	DMERR("%u 'rebuild' devices cannot be injected into"
2362	" a raid set with %u other first-time devices",
2363	rebuilds, new_devs);
2364	return -EINVAL;
2365	} else if (rebuilds) {
2366	if (rebuild_and_new && rebuilds != rebuild_and_new) {
2367	DMERR("new device%s provided without 'rebuild'",
2368	new_devs > 1 ? "s" : "");
2369	return -EINVAL;
2370	} else if (!test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && rs_is_recovering(rs)) {
2371	DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2372	(unsigned long long) mddev->recovery_cp);
2373	return -EINVAL;
2374	} else if (rs_is_reshaping(rs)) {
2375	DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2376	(unsigned long long) mddev->reshape_position);
2377	return -EINVAL;
2378	}
2379	}
2380
2381	/*
2382	* Now we set the Faulty bit for those devices that are
2383	* recorded in the superblock as failed.
2384	*/
2385	sb_retrieve_failed_devices(sb, failed_devices);
2386	rdev_for_each(r, mddev) {
2387	if (test_bit(Journal, &rdev->flags) ||
2388	!r->sb_page)
2389	continue;
2390	sb2 = page_address(r->sb_page);
2391	sb2->failed_devices = 0;
2392	memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2393
2394	/*
2395	* Check for any device re-ordering.
2396	*/
2397	if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2398	role = le32_to_cpu(sb2->array_position);
2399	if (role < 0)
2400	continue;
2401
2402	if (role != r->raid_disk) {
2403	if (rs_is_raid10(rs) && __is_raid10_near(layout: mddev->layout)) {
2404	if (mddev->raid_disks % __raid10_near_copies(layout: mddev->layout) ||
2405	rs->raid_disks % rs->raid10_copies) {
2406	rs->ti->error =
2407	"Cannot change raid10 near set to odd # of devices!";
2408	return -EINVAL;
2409	}
2410
2411	sb2->array_position = cpu_to_le32(r->raid_disk);
2412
2413	} else if (!(rs_is_raid10(rs) && rt_is_raid0(rt: rs->raid_type)) &&
2414	!(rs_is_raid0(rs) && rt_is_raid10(rt: rs->raid_type)) &&
2415	!rt_is_raid1(rt: rs->raid_type)) {
2416	rs->ti->error = "Cannot change device positions in raid set";
2417	return -EINVAL;
2418	}
2419
2420	DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2421	}
2422
2423	/*
2424	* Partial recovery is performed on
2425	* returning failed devices.
2426	*/
2427	if (test_bit(role, (void *) failed_devices))
2428	set_bit(nr: Faulty, addr: &r->flags);
2429	}
2430	}
2431
2432	return 0;
2433	}
2434
2435	static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2436	{
2437	struct mddev *mddev = &rs->md;
2438	struct dm_raid_superblock *sb;
2439
2440	if (rs_is_raid0(rs) || !rdev->sb_page || rdev->raid_disk < 0)
2441	return 0;
2442
2443	sb = page_address(rdev->sb_page);
2444
2445	/*
2446	* If mddev->events is not set, we know we have not yet initialized
2447	* the array.
2448	*/
2449	if (!mddev->events && super_init_validation(rs, rdev))
2450	return -EINVAL;
2451
2452	if (le32_to_cpu(sb->compat_features) &&
2453	le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2454	rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2455	return -EINVAL;
2456	}
2457
2458	if (sb->incompat_features) {
2459	rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2460	return -EINVAL;
2461	}
2462
2463	/* Enable bitmap creation on @rs unless no metadevs or raid0 or journaled raid4/5/6 set. */
2464	mddev->bitmap_info.offset = (rt_is_raid0(rt: rs->raid_type) || rs->journal_dev.dev) ? 0 : to_sector(n: 4096);
2465	mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2466
2467	if (!test_and_clear_bit(FirstUse, addr: &rdev->flags)) {
2468	/*
2469	* Retrieve rdev size stored in superblock to be prepared for shrink.
2470	* Check extended superblock members are present otherwise the size
2471	* will not be set!
2472	*/
2473	if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190)
2474	rdev->sectors = le64_to_cpu(sb->sectors);
2475
2476	rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2477	if (rdev->recovery_offset == MaxSector)
2478	set_bit(nr: In_sync, addr: &rdev->flags);
2479	/*
2480	* If no reshape in progress -> we're recovering single
2481	* disk(s) and have to set the device(s) to out-of-sync
2482	*/
2483	else if (!rs_is_reshaping(rs))
2484	clear_bit(nr: In_sync, addr: &rdev->flags); /* Mandatory for recovery */
2485	}
2486
2487	/*
2488	* If a device comes back, set it as not In_sync and no longer faulty.
2489	*/
2490	if (test_and_clear_bit(nr: Faulty, addr: &rdev->flags)) {
2491	rdev->recovery_offset = 0;
2492	clear_bit(nr: In_sync, addr: &rdev->flags);
2493	rdev->saved_raid_disk = rdev->raid_disk;
2494	}
2495
2496	/* Reshape support -> restore repective data offsets */
2497	rdev->data_offset = le64_to_cpu(sb->data_offset);
2498	rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2499
2500	return 0;
2501	}
2502
2503	/*
2504	* Analyse superblocks and select the freshest.
2505	*/
2506	static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2507	{
2508	int r;
2509	struct md_rdev *rdev, *freshest;
2510	struct mddev *mddev = &rs->md;
2511
2512	freshest = NULL;
2513	rdev_for_each(rdev, mddev) {
2514	if (test_bit(Journal, &rdev->flags))
2515	continue;
2516
2517	if (!rdev->meta_bdev)
2518	continue;
2519
2520	/* Set superblock offset/size for metadata device. */
2521	rdev->sb_start = 0;
2522	rdev->sb_size = bdev_logical_block_size(bdev: rdev->meta_bdev);
2523	if (rdev->sb_size < sizeof(struct dm_raid_superblock) || rdev->sb_size > PAGE_SIZE) {
2524	DMERR("superblock size of a logical block is no longer valid");
2525	return -EINVAL;
2526	}
2527
2528	/*
2529	* Skipping super_load due to CTR_FLAG_SYNC will cause
2530	* the array to undergo initialization again as
2531	* though it were new. This is the intended effect
2532	* of the "sync" directive.
2533	*
2534	* With reshaping capability added, we must ensure that
2535	* the "sync" directive is disallowed during the reshape.
2536	*/
2537	if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2538	continue;
2539
2540	r = super_load(rdev, refdev: freshest);
2541
2542	switch (r) {
2543	case 1:
2544	freshest = rdev;
2545	break;
2546	case 0:
2547	break;
2548	default:
2549	/* This is a failure to read the superblock from the metadata device. */
2550	/*
2551	* We have to keep any raid0 data/metadata device pairs or
2552	* the MD raid0 personality will fail to start the array.
2553	*/
2554	if (rs_is_raid0(rs))
2555	continue;
2556
2557	/*
2558	* We keep the dm_devs to be able to emit the device tuple
2559	* properly on the table line in raid_status() (rather than
2560	* mistakenly acting as if '- -' got passed into the constructor).
2561	*
2562	* The rdev has to stay on the same_set list to allow for
2563	* the attempt to restore faulty devices on second resume.
2564	*/
2565	rdev->raid_disk = rdev->saved_raid_disk = -1;
2566	break;
2567	}
2568	}
2569
2570	if (!freshest)
2571	return 0;
2572
2573	/*
2574	* Validation of the freshest device provides the source of
2575	* validation for the remaining devices.
2576	*/
2577	rs->ti->error = "Unable to assemble array: Invalid superblocks";
2578	if (super_validate(rs, rdev: freshest))
2579	return -EINVAL;
2580
2581	if (validate_raid_redundancy(rs)) {
2582	rs->ti->error = "Insufficient redundancy to activate array";
2583	return -EINVAL;
2584	}
2585
2586	rdev_for_each(rdev, mddev)
2587	if (!test_bit(Journal, &rdev->flags) &&
2588	rdev != freshest &&
2589	super_validate(rs, rdev))
2590	return -EINVAL;
2591	return 0;
2592	}
2593
2594	/*
2595	* Adjust data_offset and new_data_offset on all disk members of @rs
2596	* for out of place reshaping if requested by constructor
2597	*
2598	* We need free space at the beginning of each raid disk for forward
2599	* and at the end for backward reshapes which userspace has to provide
2600	* via remapping/reordering of space.
2601	*/
2602	static int rs_adjust_data_offsets(struct raid_set *rs)
2603	{
2604	sector_t data_offset = 0, new_data_offset = 0;
2605	struct md_rdev *rdev;
2606
2607	/* Constructor did not request data offset change */
2608	if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2609	if (!rs_is_reshapable(rs))
2610	goto out;
2611
2612	return 0;
2613	}
2614
2615	/* HM FIXME: get In_Sync raid_dev? */
2616	rdev = &rs->dev[0].rdev;
2617
2618	if (rs->delta_disks < 0) {
2619	/*
2620	* Removing disks (reshaping backwards):
2621	*
2622	* - before reshape: data is at offset 0 and free space
2623	* is at end of each component LV
2624	*
2625	* - after reshape: data is at offset rs->data_offset != 0 on each component LV
2626	*/
2627	data_offset = 0;
2628	new_data_offset = rs->data_offset;
2629
2630	} else if (rs->delta_disks > 0) {
2631	/*
2632	* Adding disks (reshaping forwards):
2633	*
2634	* - before reshape: data is at offset rs->data_offset != 0 and
2635	* free space is at begin of each component LV
2636	*
2637	* - after reshape: data is at offset 0 on each component LV
2638	*/
2639	data_offset = rs->data_offset;
2640	new_data_offset = 0;
2641
2642	} else {
2643	/*
2644	* User space passes in 0 for data offset after having removed reshape space
2645	*
2646	* - or - (data offset != 0)
2647	*
2648	* Changing RAID layout or chunk size -> toggle offsets
2649	*
2650	* - before reshape: data is at offset rs->data_offset 0 and
2651	* free space is at end of each component LV
2652	* -or-
2653	* data is at offset rs->data_offset != 0 and
2654	* free space is at begin of each component LV
2655	*
2656	* - after reshape: data is at offset 0 if it was at offset != 0
2657	* or at offset != 0 if it was at offset 0
2658	* on each component LV
2659	*
2660	*/
2661	data_offset = rs->data_offset ? rdev->data_offset : 0;
2662	new_data_offset = data_offset ? 0 : rs->data_offset;
2663	set_bit(RT_FLAG_UPDATE_SBS, addr: &rs->runtime_flags);
2664	}
2665
2666	/*
2667	* Make sure we got a minimum amount of free sectors per device
2668	*/
2669	if (rs->data_offset &&
2670	bdev_nr_sectors(bdev: rdev->bdev) - rs->md.dev_sectors < MIN_FREE_RESHAPE_SPACE) {
2671	rs->ti->error = data_offset ? "No space for forward reshape" :
2672	"No space for backward reshape";
2673	return -ENOSPC;
2674	}
2675	out:
2676	/*
2677	* Raise recovery_cp in case data_offset != 0 to
2678	* avoid false recovery positives in the constructor.
2679	*/
2680	if (rs->md.recovery_cp < rs->md.dev_sectors)
2681	rs->md.recovery_cp += rs->dev[0].rdev.data_offset;
2682
2683	/* Adjust data offsets on all rdevs but on any raid4/5/6 journal device */
2684	rdev_for_each(rdev, &rs->md) {
2685	if (!test_bit(Journal, &rdev->flags)) {
2686	rdev->data_offset = data_offset;
2687	rdev->new_data_offset = new_data_offset;
2688	}
2689	}
2690
2691	return 0;
2692	}
2693
2694	/* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2695	static void __reorder_raid_disk_indexes(struct raid_set *rs)
2696	{
2697	int i = 0;
2698	struct md_rdev *rdev;
2699
2700	rdev_for_each(rdev, &rs->md) {
2701	if (!test_bit(Journal, &rdev->flags)) {
2702	rdev->raid_disk = i++;
2703	rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2704	}
2705	}
2706	}
2707
2708	/*
2709	* Setup @rs for takeover by a different raid level
2710	*/
2711	static int rs_setup_takeover(struct raid_set *rs)
2712	{
2713	struct mddev *mddev = &rs->md;
2714	struct md_rdev *rdev;
2715	unsigned int d = mddev->raid_disks = rs->raid_disks;
2716	sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2717
2718	if (rt_is_raid10(rt: rs->raid_type)) {
2719	if (rs_is_raid0(rs)) {
2720	/* Userpace reordered disks -> adjust raid_disk indexes */
2721	__reorder_raid_disk_indexes(rs);
2722
2723	/* raid0 -> raid10_far layout */
2724	mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2725	copies: rs->raid10_copies);
2726	} else if (rs_is_raid1(rs))
2727	/* raid1 -> raid10_near layout */
2728	mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2729	copies: rs->raid_disks);
2730	else
2731	return -EINVAL;
2732
2733	}
2734
2735	clear_bit(nr: MD_ARRAY_FIRST_USE, addr: &mddev->flags);
2736	mddev->recovery_cp = MaxSector;
2737
2738	while (d--) {
2739	rdev = &rs->dev[d].rdev;
2740
2741	if (test_bit(d, (void *) rs->rebuild_disks)) {
2742	clear_bit(nr: In_sync, addr: &rdev->flags);
2743	clear_bit(nr: Faulty, addr: &rdev->flags);
2744	mddev->recovery_cp = rdev->recovery_offset = 0;
2745	/* Bitmap has to be created when we do an "up" takeover */
2746	set_bit(nr: MD_ARRAY_FIRST_USE, addr: &mddev->flags);
2747	}
2748
2749	rdev->new_data_offset = new_data_offset;
2750	}
2751
2752	return 0;
2753	}
2754
2755	/* Prepare @rs for reshape */
2756	static int rs_prepare_reshape(struct raid_set *rs)
2757	{
2758	bool reshape;
2759	struct mddev *mddev = &rs->md;
2760
2761	if (rs_is_raid10(rs)) {
2762	if (rs->raid_disks != mddev->raid_disks &&
2763	__is_raid10_near(layout: mddev->layout) &&
2764	rs->raid10_copies &&
2765	rs->raid10_copies != __raid10_near_copies(layout: mddev->layout)) {
2766	/*
2767	* raid disk have to be multiple of data copies to allow this conversion,
2768	*
2769	* This is actually not a reshape it is a
2770	* rebuild of any additional mirrors per group
2771	*/
2772	if (rs->raid_disks % rs->raid10_copies) {
2773	rs->ti->error = "Can't reshape raid10 mirror groups";
2774	return -EINVAL;
2775	}
2776
2777	/* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2778	__reorder_raid_disk_indexes(rs);
2779	mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2780	copies: rs->raid10_copies);
2781	mddev->new_layout = mddev->layout;
2782	reshape = false;
2783	} else
2784	reshape = true;
2785
2786	} else if (rs_is_raid456(rs))
2787	reshape = true;
2788
2789	else if (rs_is_raid1(rs)) {
2790	if (rs->delta_disks) {
2791	/* Process raid1 via delta_disks */
2792	mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
2793	reshape = true;
2794	} else {
2795	/* Process raid1 without delta_disks */
2796	mddev->raid_disks = rs->raid_disks;
2797	reshape = false;
2798	}
2799	} else {
2800	rs->ti->error = "Called with bogus raid type";
2801	return -EINVAL;
2802	}
2803
2804	if (reshape) {
2805	set_bit(RT_FLAG_RESHAPE_RS, addr: &rs->runtime_flags);
2806	set_bit(RT_FLAG_UPDATE_SBS, addr: &rs->runtime_flags);
2807	} else if (mddev->raid_disks < rs->raid_disks)
2808	/* Create new superblocks and bitmaps, if any new disks */
2809	set_bit(RT_FLAG_UPDATE_SBS, addr: &rs->runtime_flags);
2810
2811	return 0;
2812	}
2813
2814	/* Get reshape sectors from data_offsets or raid set */
2815	static sector_t _get_reshape_sectors(struct raid_set *rs)
2816	{
2817	struct md_rdev *rdev;
2818	sector_t reshape_sectors = 0;
2819
2820	rdev_for_each(rdev, &rs->md)
2821	if (!test_bit(Journal, &rdev->flags)) {
2822	reshape_sectors = (rdev->data_offset > rdev->new_data_offset) ?
2823	rdev->data_offset - rdev->new_data_offset :
2824	rdev->new_data_offset - rdev->data_offset;
2825	break;
2826	}
2827
2828	return max(reshape_sectors, (sector_t) rs->data_offset);
2829	}
2830
2831	/*
2832	* Reshape:
2833	* - change raid layout
2834	* - change chunk size
2835	* - add disks
2836	* - remove disks
2837	*/
2838	static int rs_setup_reshape(struct raid_set *rs)
2839	{
2840	int r = 0;
2841	unsigned int cur_raid_devs, d;
2842	sector_t reshape_sectors = _get_reshape_sectors(rs);
2843	struct mddev *mddev = &rs->md;
2844	struct md_rdev *rdev;
2845
2846	mddev->delta_disks = rs->delta_disks;
2847	cur_raid_devs = mddev->raid_disks;
2848
2849	/* Ignore impossible layout change whilst adding/removing disks */
2850	if (mddev->delta_disks &&
2851	mddev->layout != mddev->new_layout) {
2852	DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2853	mddev->new_layout = mddev->layout;
2854	}
2855
2856	/*
2857	* Adjust array size:
2858	*
2859	* - in case of adding disk(s), array size has
2860	* to grow after the disk adding reshape,
2861	* which'll happen in the event handler;
2862	* reshape will happen forward, so space has to
2863	* be available at the beginning of each disk
2864	*
2865	* - in case of removing disk(s), array size
2866	* has to shrink before starting the reshape,
2867	* which'll happen here;
2868	* reshape will happen backward, so space has to
2869	* be available at the end of each disk
2870	*
2871	* - data_offset and new_data_offset are
2872	* adjusted for aforementioned out of place
2873	* reshaping based on userspace passing in
2874	* the "data_offset <sectors>" key/value
2875	* pair via the constructor
2876	*/
2877
2878	/* Add disk(s) */
2879	if (rs->delta_disks > 0) {
2880	/* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2881	for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2882	rdev = &rs->dev[d].rdev;
2883	clear_bit(nr: In_sync, addr: &rdev->flags);
2884
2885	/*
2886	* save_raid_disk needs to be -1, or recovery_offset will be set to 0
2887	* by md, which'll store that erroneously in the superblock on reshape
2888	*/
2889	rdev->saved_raid_disk = -1;
2890	rdev->raid_disk = d;
2891
2892	rdev->sectors = mddev->dev_sectors;
2893	rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
2894	}
2895
2896	mddev->reshape_backwards = 0; /* adding disk(s) -> forward reshape */
2897
2898	/* Remove disk(s) */
2899	} else if (rs->delta_disks < 0) {
2900	r = rs_set_dev_and_array_sectors(rs, sectors: rs->ti->len, use_mddev: true);
2901	mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2902
2903	/* Change layout and/or chunk size */
2904	} else {
2905	/*
2906	* Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2907	*
2908	* keeping number of disks and do layout change ->
2909	*
2910	* toggle reshape_backward depending on data_offset:
2911	*
2912	* - free space upfront -> reshape forward
2913	*
2914	* - free space at the end -> reshape backward
2915	*
2916	*
2917	* This utilizes free reshape space avoiding the need
2918	* for userspace to move (parts of) LV segments in
2919	* case of layout/chunksize change (for disk
2920	* adding/removing reshape space has to be at
2921	* the proper address (see above with delta_disks):
2922	*
2923	* add disk(s) -> begin
2924	* remove disk(s)-> end
2925	*/
2926	mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2927	}
2928
2929	/*
2930	* Adjust device size for forward reshape
2931	* because md_finish_reshape() reduces it.
2932	*/
2933	if (!mddev->reshape_backwards)
2934	rdev_for_each(rdev, &rs->md)
2935	if (!test_bit(Journal, &rdev->flags))
2936	rdev->sectors += reshape_sectors;
2937
2938	return r;
2939	}
2940
2941	/*
2942	* If the md resync thread has updated superblock with max reshape position
2943	* at the end of a reshape but not (yet) reset the layout configuration
2944	* changes -> reset the latter.
2945	*/
2946	static void rs_reset_inconclusive_reshape(struct raid_set *rs)
2947	{
2948	if (!rs_is_reshaping(rs) && rs_is_layout_change(rs, use_mddev: true)) {
2949	rs_set_cur(rs);
2950	rs->md.delta_disks = 0;
2951	rs->md.reshape_backwards = 0;
2952	}
2953	}
2954
2955	/*
2956	* Enable/disable discard support on RAID set depending on
2957	* RAID level and discard properties of underlying RAID members.
2958	*/
2959	static void configure_discard_support(struct raid_set *rs)
2960	{
2961	int i;
2962	bool raid456;
2963	struct dm_target *ti = rs->ti;
2964
2965	/*
2966	* XXX: RAID level 4,5,6 require zeroing for safety.
2967	*/
2968	raid456 = rs_is_raid456(rs);
2969
2970	for (i = 0; i < rs->raid_disks; i++) {
2971	if (!rs->dev[i].rdev.bdev ||
2972	!bdev_max_discard_sectors(bdev: rs->dev[i].rdev.bdev))
2973	return;
2974
2975	if (raid456) {
2976	if (!devices_handle_discard_safely) {
2977	DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2978	DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2979	return;
2980	}
2981	}
2982	}
2983
2984	ti->num_discard_bios = 1;
2985	}
2986
2987	/*
2988	* Construct a RAID0/1/10/4/5/6 mapping:
2989	* Args:
2990	* <raid_type> <#raid_params> <raid_params>{0,} \
2991	* <#raid_devs> [<meta_dev1> <dev1>]{1,}
2992	*
2993	* <raid_params> varies by <raid_type>. See 'parse_raid_params' for
2994	* details on possible <raid_params>.
2995	*
2996	* Userspace is free to initialize the metadata devices, hence the superblocks to
2997	* enforce recreation based on the passed in table parameters.
2998	*
2999	*/
3000	static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
3001	{
3002	int r;
3003	bool resize = false;
3004	struct raid_type *rt;
3005	unsigned int num_raid_params, num_raid_devs;
3006	sector_t sb_array_sectors, rdev_sectors, reshape_sectors;
3007	struct raid_set *rs = NULL;
3008	const char *arg;
3009	struct rs_layout rs_layout;
3010	struct dm_arg_set as = { argc, argv }, as_nrd;
3011	struct dm_arg _args[] = {
3012	{ 0, as.argc, "Cannot understand number of raid parameters" },
3013	{ 1, 254, "Cannot understand number of raid devices parameters" }
3014	};
3015
3016	arg = dm_shift_arg(as: &as);
3017	if (!arg) {
3018	ti->error = "No arguments";
3019	return -EINVAL;
3020	}
3021
3022	rt = get_raid_type(name: arg);
3023	if (!rt) {
3024	ti->error = "Unrecognised raid_type";
3025	return -EINVAL;
3026	}
3027
3028	/* Must have <#raid_params> */
3029	if (dm_read_arg_group(arg: _args, arg_set: &as, num_args: &num_raid_params, error: &ti->error))
3030	return -EINVAL;
3031
3032	/* number of raid device tupples <meta_dev data_dev> */
3033	as_nrd = as;
3034	dm_consume_args(as: &as_nrd, num_args: num_raid_params);
3035	_args[1].max = (as_nrd.argc - 1) / 2;
3036	if (dm_read_arg(arg: _args + 1, arg_set: &as_nrd, value: &num_raid_devs, error: &ti->error))
3037	return -EINVAL;
3038
3039	if (!__within_range(v: num_raid_devs, min: 1, MAX_RAID_DEVICES)) {
3040	ti->error = "Invalid number of supplied raid devices";
3041	return -EINVAL;
3042	}
3043
3044	rs = raid_set_alloc(ti, raid_type: rt, raid_devs: num_raid_devs);
3045	if (IS_ERR(ptr: rs))
3046	return PTR_ERR(ptr: rs);
3047
3048	r = parse_raid_params(rs, as: &as, num_raid_params);
3049	if (r)
3050	goto bad;
3051
3052	r = parse_dev_params(rs, as: &as);
3053	if (r)
3054	goto bad;
3055
3056	rs->md.sync_super = super_sync;
3057
3058	/*
3059	* Calculate ctr requested array and device sizes to allow
3060	* for superblock analysis needing device sizes defined.
3061	*
3062	* Any existing superblock will overwrite the array and device sizes
3063	*/
3064	r = rs_set_dev_and_array_sectors(rs, sectors: rs->ti->len, use_mddev: false);
3065	if (r)
3066	goto bad;
3067
3068	/* Memorize just calculated, potentially larger sizes to grow the raid set in preresume */
3069	rs->array_sectors = rs->md.array_sectors;
3070	rs->dev_sectors = rs->md.dev_sectors;
3071
3072	/*
3073	* Backup any new raid set level, layout, ...
3074	* requested to be able to compare to superblock
3075	* members for conversion decisions.
3076	*/
3077	rs_config_backup(rs, l: &rs_layout);
3078
3079	r = analyse_superblocks(ti, rs);
3080	if (r)
3081	goto bad;
3082
3083	/* All in-core metadata now as of current superblocks after calling analyse_superblocks() */
3084	sb_array_sectors = rs->md.array_sectors;
3085	rdev_sectors = __rdev_sectors(rs);
3086	if (!rdev_sectors) {
3087	ti->error = "Invalid rdev size";
3088	r = -EINVAL;
3089	goto bad;
3090	}
3091
3092
3093	reshape_sectors = _get_reshape_sectors(rs);
3094	if (rs->dev_sectors != rdev_sectors) {
3095	resize = (rs->dev_sectors != rdev_sectors - reshape_sectors);
3096	if (rs->dev_sectors > rdev_sectors - reshape_sectors)
3097	set_bit(RT_FLAG_RS_GROW, addr: &rs->runtime_flags);
3098	}
3099
3100	INIT_WORK(&rs->md.event_work, do_table_event);
3101	ti->private = rs;
3102	ti->num_flush_bios = 1;
3103	ti->needs_bio_set_dev = true;
3104
3105	/* Restore any requested new layout for conversion decision */
3106	rs_config_restore(rs, l: &rs_layout);
3107
3108	/*
3109	* Now that we have any superblock metadata available,
3110	* check for new, recovering, reshaping, to be taken over,
3111	* to be reshaped or an existing, unchanged raid set to
3112	* run in sequence.
3113	*/
3114	if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
3115	/* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
3116	if (rs_is_raid6(rs) &&
3117	test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
3118	ti->error = "'nosync' not allowed for new raid6 set";
3119	r = -EINVAL;
3120	goto bad;
3121	}
3122	rs_setup_recovery(rs, dev_sectors: 0);
3123	set_bit(RT_FLAG_UPDATE_SBS, addr: &rs->runtime_flags);
3124	rs_set_new(rs);
3125	} else if (rs_is_recovering(rs)) {
3126	/* A recovering raid set may be resized */
3127	goto size_check;
3128	} else if (rs_is_reshaping(rs)) {
3129	/* Have to reject size change request during reshape */
3130	if (resize) {
3131	ti->error = "Can't resize a reshaping raid set";
3132	r = -EPERM;
3133	goto bad;
3134	}
3135	/* skip setup rs */
3136	} else if (rs_takeover_requested(rs)) {
3137	if (rs_is_reshaping(rs)) {
3138	ti->error = "Can't takeover a reshaping raid set";
3139	r = -EPERM;
3140	goto bad;
3141	}
3142
3143	/* We can't takeover a journaled raid4/5/6 */
3144	if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3145	ti->error = "Can't takeover a journaled raid4/5/6 set";
3146	r = -EPERM;
3147	goto bad;
3148	}
3149
3150	/*
3151	* If a takeover is needed, userspace sets any additional
3152	* devices to rebuild and we can check for a valid request here.
3153	*
3154	* If acceptable, set the level to the new requested
3155	* one, prohibit requesting recovery, allow the raid
3156	* set to run and store superblocks during resume.
3157	*/
3158	r = rs_check_takeover(rs);
3159	if (r)
3160	goto bad;
3161
3162	r = rs_setup_takeover(rs);
3163	if (r)
3164	goto bad;
3165
3166	set_bit(RT_FLAG_UPDATE_SBS, addr: &rs->runtime_flags);
3167	/* Takeover ain't recovery, so disable recovery */
3168	rs_setup_recovery(rs, MaxSector);
3169	rs_set_new(rs);
3170	} else if (rs_reshape_requested(rs)) {
3171	/* Only request grow on raid set size extensions, not on reshapes. */
3172	clear_bit(RT_FLAG_RS_GROW, addr: &rs->runtime_flags);
3173
3174	/*
3175	* No need to check for 'ongoing' takeover here, because takeover
3176	* is an instant operation as oposed to an ongoing reshape.
3177	*/
3178
3179	/* We can't reshape a journaled raid4/5/6 */
3180	if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3181	ti->error = "Can't reshape a journaled raid4/5/6 set";
3182	r = -EPERM;
3183	goto bad;
3184	}
3185
3186	/* Out-of-place space has to be available to allow for a reshape unless raid1! */
3187	if (reshape_sectors || rs_is_raid1(rs)) {
3188	/*
3189	* We can only prepare for a reshape here, because the
3190	* raid set needs to run to provide the repective reshape
3191	* check functions via its MD personality instance.
3192	*
3193	* So do the reshape check after md_run() succeeded.
3194	*/
3195	r = rs_prepare_reshape(rs);
3196	if (r)
3197	goto bad;
3198
3199	/* Reshaping ain't recovery, so disable recovery */
3200	rs_setup_recovery(rs, MaxSector);
3201	}
3202	rs_set_cur(rs);
3203	} else {
3204	size_check:
3205	/* May not set recovery when a device rebuild is requested */
3206	if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
3207	clear_bit(RT_FLAG_RS_GROW, addr: &rs->runtime_flags);
3208	set_bit(RT_FLAG_UPDATE_SBS, addr: &rs->runtime_flags);
3209	rs_setup_recovery(rs, MaxSector);
3210	} else if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
3211	/*
3212	* Set raid set to current size, i.e. size as of
3213	* superblocks to grow to larger size in preresume.
3214	*/
3215	r = rs_set_dev_and_array_sectors(rs, sectors: sb_array_sectors, use_mddev: false);
3216	if (r)
3217	goto bad;
3218
3219	rs_setup_recovery(rs, dev_sectors: rs->md.recovery_cp < rs->md.dev_sectors ? rs->md.recovery_cp : rs->md.dev_sectors);
3220	} else {
3221	/* This is no size change or it is shrinking, update size and record in superblocks */
3222	r = rs_set_dev_and_array_sectors(rs, sectors: rs->ti->len, use_mddev: false);
3223	if (r)
3224	goto bad;
3225
3226	if (sb_array_sectors > rs->array_sectors)
3227	set_bit(RT_FLAG_UPDATE_SBS, addr: &rs->runtime_flags);
3228	}
3229	rs_set_cur(rs);
3230	}
3231
3232	/* If constructor requested it, change data and new_data offsets */
3233	r = rs_adjust_data_offsets(rs);
3234	if (r)
3235	goto bad;
3236
3237	/* Catch any inconclusive reshape superblock content. */
3238	rs_reset_inconclusive_reshape(rs);
3239
3240	/* Start raid set read-only and assumed clean to change in raid_resume() */
3241	rs->md.ro = 1;
3242	rs->md.in_sync = 1;
3243
3244	/* Has to be held on running the array */
3245	mddev_suspend_and_lock_nointr(mddev: &rs->md);
3246
3247	/* Keep array frozen until resume. */
3248	md_frozen_sync_thread(mddev: &rs->md);
3249
3250	r = md_run(mddev: &rs->md);
3251	rs->md.in_sync = 0; /* Assume already marked dirty */
3252	if (r) {
3253	ti->error = "Failed to run raid array";
3254	mddev_unlock(mddev: &rs->md);
3255	goto bad;
3256	}
3257
3258	r = md_start(mddev: &rs->md);
3259	if (r) {
3260	ti->error = "Failed to start raid array";
3261	goto bad_unlock;
3262	}
3263
3264	/* If raid4/5/6 journal mode explicitly requested (only possible with journal dev) -> set it */
3265	if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
3266	r = r5c_journal_mode_set(mddev: &rs->md, journal_mode: rs->journal_dev.mode);
3267	if (r) {
3268	ti->error = "Failed to set raid4/5/6 journal mode";
3269	goto bad_unlock;
3270	}
3271	}
3272
3273	set_bit(RT_FLAG_RS_SUSPENDED, addr: &rs->runtime_flags);
3274
3275	/* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
3276	if (rs_is_raid456(rs)) {
3277	r = rs_set_raid456_stripe_cache(rs);
3278	if (r)
3279	goto bad_unlock;
3280	}
3281
3282	/* Now do an early reshape check */
3283	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3284	r = rs_check_reshape(rs);
3285	if (r)
3286	goto bad_unlock;
3287
3288	/* Restore new, ctr requested layout to perform check */
3289	rs_config_restore(rs, l: &rs_layout);
3290
3291	if (rs->md.pers->start_reshape) {
3292	r = rs->md.pers->check_reshape(&rs->md);
3293	if (r) {
3294	ti->error = "Reshape check failed";
3295	goto bad_unlock;
3296	}
3297	}
3298	}
3299
3300	/* Disable/enable discard support on raid set. */
3301	configure_discard_support(rs);
3302
3303	mddev_unlock(mddev: &rs->md);
3304	return 0;
3305
3306	bad_unlock:
3307	md_stop(mddev: &rs->md);
3308	mddev_unlock(mddev: &rs->md);
3309	bad:
3310	raid_set_free(rs);
3311
3312	return r;
3313	}
3314
3315	static void raid_dtr(struct dm_target *ti)
3316	{
3317	struct raid_set *rs = ti->private;
3318
3319	mddev_lock_nointr(mddev: &rs->md);
3320	md_stop(mddev: &rs->md);
3321	mddev_unlock(mddev: &rs->md);
3322
3323	if (work_pending(&rs->md.event_work))
3324	flush_work(work: &rs->md.event_work);
3325	raid_set_free(rs);
3326	}
3327
3328	static int raid_map(struct dm_target *ti, struct bio *bio)
3329	{
3330	struct raid_set *rs = ti->private;
3331	struct mddev *mddev = &rs->md;
3332
3333	/*
3334	* If we're reshaping to add disk(s), ti->len and
3335	* mddev->array_sectors will differ during the process
3336	* (ti->len > mddev->array_sectors), so we have to requeue
3337	* bios with addresses > mddev->array_sectors here or
3338	* there will occur accesses past EOD of the component
3339	* data images thus erroring the raid set.
3340	*/
3341	if (unlikely(bio_has_data(bio) && bio_end_sector(bio) > mddev->array_sectors))
3342	return DM_MAPIO_REQUEUE;
3343
3344	if (unlikely(!md_handle_request(mddev, bio)))
3345	return DM_MAPIO_REQUEUE;
3346
3347	return DM_MAPIO_SUBMITTED;
3348	}
3349
3350	/* Return sync state string for @state */
3351	enum sync_state { st_frozen, st_reshape, st_resync, st_check, st_repair, st_recover, st_idle };
3352	static const char *sync_str(enum sync_state state)
3353	{
3354	/* Has to be in above sync_state order! */
3355	static const char *sync_strs[] = {
3356	"frozen",
3357	"reshape",
3358	"resync",
3359	"check",
3360	"repair",
3361	"recover",
3362	"idle"
3363	};
3364
3365	return __within_range(v: state, min: 0, ARRAY_SIZE(sync_strs) - 1) ? sync_strs[state] : "undef";
3366	};
3367
3368	/* Return enum sync_state for @mddev derived from @recovery flags */
3369	static enum sync_state decipher_sync_action(struct mddev *mddev, unsigned long recovery)
3370	{
3371	if (test_bit(MD_RECOVERY_FROZEN, &recovery))
3372	return st_frozen;
3373
3374	/* The MD sync thread can be done with io or be interrupted but still be running */
3375	if (!test_bit(MD_RECOVERY_DONE, &recovery) &&
3376	(test_bit(MD_RECOVERY_RUNNING, &recovery) ||
3377	(!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery)))) {
3378	if (test_bit(MD_RECOVERY_RESHAPE, &recovery))
3379	return st_reshape;
3380
3381	if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
3382	if (!test_bit(MD_RECOVERY_REQUESTED, &recovery))
3383	return st_resync;
3384	if (test_bit(MD_RECOVERY_CHECK, &recovery))
3385	return st_check;
3386	return st_repair;
3387	}
3388
3389	if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3390	return st_recover;
3391
3392	if (mddev->reshape_position != MaxSector)
3393	return st_reshape;
3394	}
3395
3396	return st_idle;
3397	}
3398
3399	/*
3400	* Return status string for @rdev
3401	*
3402	* Status characters:
3403	*
3404	* 'D' = Dead/Failed raid set component or raid4/5/6 journal device
3405	* 'a' = Alive but not in-sync raid set component _or_ alive raid4/5/6 'write_back' journal device
3406	* 'A' = Alive and in-sync raid set component _or_ alive raid4/5/6 'write_through' journal device
3407	* '-' = Non-existing device (i.e. uspace passed '- -' into the ctr)
3408	*/
3409	static const char *__raid_dev_status(struct raid_set *rs, struct md_rdev *rdev)
3410	{
3411	if (!rdev->bdev)
3412	return "-";
3413	else if (test_bit(Faulty, &rdev->flags))
3414	return "D";
3415	else if (test_bit(Journal, &rdev->flags))
3416	return (rs->journal_dev.mode == R5C_JOURNAL_MODE_WRITE_THROUGH) ? "A" : "a";
3417	else if (test_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags) ||
3418	(!test_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags) &&
3419	!test_bit(In_sync, &rdev->flags)))
3420	return "a";
3421	else
3422	return "A";
3423	}
3424
3425	/* Helper to return resync/reshape progress for @rs and runtime flags for raid set in sync / resynching */
3426	static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery,
3427	enum sync_state state, sector_t resync_max_sectors)
3428	{
3429	sector_t r;
3430	struct mddev *mddev = &rs->md;
3431
3432	clear_bit(RT_FLAG_RS_IN_SYNC, addr: &rs->runtime_flags);
3433	clear_bit(RT_FLAG_RS_RESYNCING, addr: &rs->runtime_flags);
3434
3435	if (rs_is_raid0(rs)) {
3436	r = resync_max_sectors;
3437	set_bit(RT_FLAG_RS_IN_SYNC, addr: &rs->runtime_flags);
3438
3439	} else {
3440	if (state == st_idle && !test_bit(MD_RECOVERY_INTR, &recovery))
3441	r = mddev->recovery_cp;
3442	else
3443	r = mddev->curr_resync_completed;
3444
3445	if (state == st_idle && r >= resync_max_sectors) {
3446	/*
3447	* Sync complete.
3448	*/
3449	/* In case we have finished recovering, the array is in sync. */
3450	if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3451	set_bit(RT_FLAG_RS_IN_SYNC, addr: &rs->runtime_flags);
3452
3453	} else if (state == st_recover)
3454	/*
3455	* In case we are recovering, the array is not in sync
3456	* and health chars should show the recovering legs.
3457	*
3458	* Already retrieved recovery offset from curr_resync_completed above.
3459	*/
3460	;
3461
3462	else if (state == st_resync || state == st_reshape)
3463	/*
3464	* If "resync/reshape" is occurring, the raid set
3465	* is or may be out of sync hence the health
3466	* characters shall be 'a'.
3467	*/
3468	set_bit(RT_FLAG_RS_RESYNCING, addr: &rs->runtime_flags);
3469
3470	else if (state == st_check || state == st_repair)
3471	/*
3472	* If "check" or "repair" is occurring, the raid set has
3473	* undergone an initial sync and the health characters
3474	* should not be 'a' anymore.
3475	*/
3476	set_bit(RT_FLAG_RS_IN_SYNC, addr: &rs->runtime_flags);
3477
3478	else if (test_bit(MD_RECOVERY_NEEDED, &recovery))
3479	/*
3480	* We are idle and recovery is needed, prevent 'A' chars race
3481	* caused by components still set to in-sync by constructor.
3482	*/
3483	set_bit(RT_FLAG_RS_RESYNCING, addr: &rs->runtime_flags);
3484
3485	else {
3486	/*
3487	* We are idle and the raid set may be doing an initial
3488	* sync, or it may be rebuilding individual components.
3489	* If all the devices are In_sync, then it is the raid set
3490	* that is being initialized.
3491	*/
3492	struct md_rdev *rdev;
3493
3494	set_bit(RT_FLAG_RS_IN_SYNC, addr: &rs->runtime_flags);
3495	rdev_for_each(rdev, mddev)
3496	if (!test_bit(Journal, &rdev->flags) &&
3497	!test_bit(In_sync, &rdev->flags)) {
3498	clear_bit(RT_FLAG_RS_IN_SYNC, addr: &rs->runtime_flags);
3499	break;
3500	}
3501	}
3502	}
3503
3504	return min(r, resync_max_sectors);
3505	}
3506
3507	/* Helper to return @dev name or "-" if !@dev */
3508	static const char *__get_dev_name(struct dm_dev *dev)
3509	{
3510	return dev ? dev->name : "-";
3511	}
3512
3513	static void raid_status(struct dm_target *ti, status_type_t type,
3514	unsigned int status_flags, char *result, unsigned int maxlen)
3515	{
3516	struct raid_set *rs = ti->private;
3517	struct mddev *mddev = &rs->md;
3518	struct r5conf *conf = rs_is_raid456(rs) ? mddev->private : NULL;
3519	int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3520	unsigned long recovery;
3521	unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3522	unsigned int sz = 0;
3523	unsigned int rebuild_writemostly_count = 0;
3524	sector_t progress, resync_max_sectors, resync_mismatches;
3525	enum sync_state state;
3526	struct raid_type *rt;
3527
3528	switch (type) {
3529	case STATUSTYPE_INFO:
3530	/* *Should* always succeed */
3531	rt = get_raid_type_by_ll(level: mddev->new_level, layout: mddev->new_layout);
3532	if (!rt)
3533	return;
3534
3535	DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3536
3537	/* Access most recent mddev properties for status output */
3538	smp_rmb();
3539	/* Get sensible max sectors even if raid set not yet started */
3540	resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3541	mddev->resync_max_sectors : mddev->dev_sectors;
3542	recovery = rs->md.recovery;
3543	state = decipher_sync_action(mddev, recovery);
3544	progress = rs_get_progress(rs, recovery, state, resync_max_sectors);
3545	resync_mismatches = (mddev->last_sync_action && !strcasecmp(s1: mddev->last_sync_action, s2: "check")) ?
3546	atomic64_read(v: &mddev->resync_mismatches) : 0;
3547
3548	/* HM FIXME: do we want another state char for raid0? It shows 'D'/'A'/'-' now */
3549	for (i = 0; i < rs->raid_disks; i++)
3550	DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3551
3552	/*
3553	* In-sync/Reshape ratio:
3554	* The in-sync ratio shows the progress of:
3555	* - Initializing the raid set
3556	* - Rebuilding a subset of devices of the raid set
3557	* The user can distinguish between the two by referring
3558	* to the status characters.
3559	*
3560	* The reshape ratio shows the progress of
3561	* changing the raid layout or the number of
3562	* disks of a raid set
3563	*/
3564	DMEMIT(" %llu/%llu", (unsigned long long) progress,
3565	(unsigned long long) resync_max_sectors);
3566
3567	/*
3568	* v1.5.0+:
3569	*
3570	* Sync action:
3571	* See Documentation/admin-guide/device-mapper/dm-raid.rst for
3572	* information on each of these states.
3573	*/
3574	DMEMIT(" %s", sync_str(state));
3575
3576	/*
3577	* v1.5.0+:
3578	*
3579	* resync_mismatches/mismatch_cnt
3580	* This field shows the number of discrepancies found when
3581	* performing a "check" of the raid set.
3582	*/
3583	DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3584
3585	/*
3586	* v1.9.0+:
3587	*
3588	* data_offset (needed for out of space reshaping)
3589	* This field shows the data offset into the data
3590	* image LV where the first stripes data starts.
3591	*
3592	* We keep data_offset equal on all raid disks of the set,
3593	* so retrieving it from the first raid disk is sufficient.
3594	*/
3595	DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
3596
3597	/*
3598	* v1.10.0+:
3599	*/
3600	DMEMIT(" %s", test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags) ?
3601	__raid_dev_status(rs, &rs->journal_dev.rdev) : "-");
3602	break;
3603
3604	case STATUSTYPE_TABLE:
3605	/* Report the table line string you would use to construct this raid set */
3606
3607	/*
3608	* Count any rebuild or writemostly argument pairs and subtract the
3609	* hweight count being added below of any rebuild and writemostly ctr flags.
3610	*/
3611	for (i = 0; i < rs->raid_disks; i++) {
3612	rebuild_writemostly_count += (test_bit(i, (void *) rs->rebuild_disks) ? 2 : 0) +
3613	(test_bit(WriteMostly, &rs->dev[i].rdev.flags) ? 2 : 0);
3614	}
3615	rebuild_writemostly_count -= (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) ? 2 : 0) +
3616	(test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags) ? 2 : 0);
3617	/* Calculate raid parameter count based on ^ rebuild/writemostly argument counts and ctr flags set. */
3618	raid_param_cnt += rebuild_writemostly_count +
3619	hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3620	hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
3621	/* Emit table line */
3622	/* This has to be in the documented order for userspace! */
3623	DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3624	if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3625	DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
3626	if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3627	DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3628	if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags))
3629	for (i = 0; i < rs->raid_disks; i++)
3630	if (test_bit(i, (void *) rs->rebuild_disks))
3631	DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD), i);
3632	if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3633	DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3634	mddev->bitmap_info.daemon_sleep);
3635	if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3636	DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3637	mddev->sync_speed_min);
3638	if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3639	DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3640	mddev->sync_speed_max);
3641	if (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags))
3642	for (i = 0; i < rs->raid_disks; i++)
3643	if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3644	DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3645	rs->dev[i].rdev.raid_disk);
3646	if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3647	DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3648	mddev->bitmap_info.max_write_behind);
3649	if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3650	DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3651	max_nr_stripes);
3652	if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3653	DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3654	(unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3655	if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3656	DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3657	raid10_md_layout_to_copies(mddev->layout));
3658	if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3659	DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3660	raid10_md_layout_to_format(mddev->layout));
3661	if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3662	DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3663	max(rs->delta_disks, mddev->delta_disks));
3664	if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3665	DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3666	(unsigned long long) rs->data_offset);
3667	if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags))
3668	DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV),
3669	__get_dev_name(rs->journal_dev.dev));
3670	if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags))
3671	DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE),
3672	md_journal_mode_to_dm_raid(rs->journal_dev.mode));
3673	DMEMIT(" %d", rs->raid_disks);
3674	for (i = 0; i < rs->raid_disks; i++)
3675	DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
3676	__get_dev_name(rs->dev[i].data_dev));
3677	break;
3678
3679	case STATUSTYPE_IMA:
3680	rt = get_raid_type_by_ll(level: mddev->new_level, layout: mddev->new_layout);
3681	if (!rt)
3682	return;
3683
3684	DMEMIT_TARGET_NAME_VERSION(ti->type);
3685	DMEMIT(",raid_type=%s,raid_disks=%d", rt->name, mddev->raid_disks);
3686
3687	/* Access most recent mddev properties for status output */
3688	smp_rmb();
3689	recovery = rs->md.recovery;
3690	state = decipher_sync_action(mddev, recovery);
3691	DMEMIT(",raid_state=%s", sync_str(state));
3692
3693	for (i = 0; i < rs->raid_disks; i++) {
3694	DMEMIT(",raid_device_%d_status=", i);
3695	DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3696	}
3697
3698	if (rt_is_raid456(rt)) {
3699	DMEMIT(",journal_dev_mode=");
3700	switch (rs->journal_dev.mode) {
3701	case R5C_JOURNAL_MODE_WRITE_THROUGH:
3702	DMEMIT("%s",
3703	_raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_THROUGH].param);
3704	break;
3705	case R5C_JOURNAL_MODE_WRITE_BACK:
3706	DMEMIT("%s",
3707	_raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_BACK].param);
3708	break;
3709	default:
3710	DMEMIT("invalid");
3711	break;
3712	}
3713	}
3714	DMEMIT(";");
3715	break;
3716	}
3717	}
3718
3719	static int raid_message(struct dm_target *ti, unsigned int argc, char **argv,
3720	char *result, unsigned int maxlen)
3721	{
3722	struct raid_set *rs = ti->private;
3723	struct mddev *mddev = &rs->md;
3724	int ret = 0;
3725
3726	if (!mddev->pers || !mddev->pers->sync_request)
3727	return -EINVAL;
3728
3729	if (test_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags) ||
3730	test_bit(RT_FLAG_RS_FROZEN, &rs->runtime_flags))
3731	return -EBUSY;
3732
3733	if (!strcasecmp(s1: argv[0], s2: "frozen")) {
3734	ret = mddev_lock(mddev);
3735	if (ret)
3736	return ret;
3737
3738	md_frozen_sync_thread(mddev);
3739	mddev_unlock(mddev);
3740	} else if (!strcasecmp(s1: argv[0], s2: "idle")) {
3741	ret = mddev_lock(mddev);
3742	if (ret)
3743	return ret;
3744
3745	md_idle_sync_thread(mddev);
3746	mddev_unlock(mddev);
3747	}
3748
3749	clear_bit(nr: MD_RECOVERY_FROZEN, addr: &mddev->recovery);
3750	if (decipher_sync_action(mddev, recovery: mddev->recovery) != st_idle)
3751	return -EBUSY;
3752	else if (!strcasecmp(s1: argv[0], s2: "resync"))
3753	; /* MD_RECOVERY_NEEDED set below */
3754	else if (!strcasecmp(s1: argv[0], s2: "recover"))
3755	set_bit(nr: MD_RECOVERY_RECOVER, addr: &mddev->recovery);
3756	else {
3757	if (!strcasecmp(s1: argv[0], s2: "check")) {
3758	set_bit(nr: MD_RECOVERY_CHECK, addr: &mddev->recovery);
3759	set_bit(nr: MD_RECOVERY_REQUESTED, addr: &mddev->recovery);
3760	set_bit(nr: MD_RECOVERY_SYNC, addr: &mddev->recovery);
3761	} else if (!strcasecmp(s1: argv[0], s2: "repair")) {
3762	set_bit(nr: MD_RECOVERY_REQUESTED, addr: &mddev->recovery);
3763	set_bit(nr: MD_RECOVERY_SYNC, addr: &mddev->recovery);
3764	} else
3765	return -EINVAL;
3766	}
3767	if (mddev->ro == 2) {
3768	/* A write to sync_action is enough to justify
3769	* canceling read-auto mode
3770	*/
3771	mddev->ro = 0;
3772	if (!mddev->suspended)
3773	md_wakeup_thread(thread: mddev->sync_thread);
3774	}
3775	set_bit(nr: MD_RECOVERY_NEEDED, addr: &mddev->recovery);
3776	if (!mddev->suspended)
3777	md_wakeup_thread(thread: mddev->thread);
3778
3779	return 0;
3780	}
3781
3782	static int raid_iterate_devices(struct dm_target *ti,
3783	iterate_devices_callout_fn fn, void *data)
3784	{
3785	struct raid_set *rs = ti->private;
3786	unsigned int i;
3787	int r = 0;
3788
3789	for (i = 0; !r && i < rs->raid_disks; i++) {
3790	if (rs->dev[i].data_dev) {
3791	r = fn(ti, rs->dev[i].data_dev,
3792	0, /* No offset on data devs */
3793	rs->md.dev_sectors, data);
3794	}
3795	}
3796
3797	return r;
3798	}
3799
3800	static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3801	{
3802	struct raid_set *rs = ti->private;
3803	unsigned int chunk_size_bytes = to_bytes(n: rs->md.chunk_sectors);
3804
3805	blk_limits_io_min(limits, min: chunk_size_bytes);
3806	blk_limits_io_opt(limits, opt: chunk_size_bytes * mddev_data_stripes(rs));
3807	}
3808
3809	static void raid_presuspend(struct dm_target *ti)
3810	{
3811	struct raid_set *rs = ti->private;
3812	struct mddev *mddev = &rs->md;
3813
3814	/*
3815	* From now on, disallow raid_message() to change sync_thread until
3816	* resume, raid_postsuspend() is too late.
3817	*/
3818	set_bit(RT_FLAG_RS_FROZEN, addr: &rs->runtime_flags);
3819
3820	if (!reshape_interrupted(mddev))
3821	return;
3822
3823	/*
3824	* For raid456, if reshape is interrupted, IO across reshape position
3825	* will never make progress, while caller will wait for IO to be done.
3826	* Inform raid456 to handle those IO to prevent deadlock.
3827	*/
3828	if (mddev->pers && mddev->pers->prepare_suspend)
3829	mddev->pers->prepare_suspend(mddev);
3830	}
3831
3832	static void raid_presuspend_undo(struct dm_target *ti)
3833	{
3834	struct raid_set *rs = ti->private;
3835
3836	clear_bit(RT_FLAG_RS_FROZEN, addr: &rs->runtime_flags);
3837	}
3838
3839	static void raid_postsuspend(struct dm_target *ti)
3840	{
3841	struct raid_set *rs = ti->private;
3842
3843	if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, addr: &rs->runtime_flags)) {
3844	/*
3845	* sync_thread must be stopped during suspend, and writes have
3846	* to be stopped before suspending to avoid deadlocks.
3847	*/
3848	md_stop_writes(mddev: &rs->md);
3849	mddev_suspend(mddev: &rs->md, interruptible: false);
3850	}
3851	}
3852
3853	static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3854	{
3855	int i;
3856	uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];
3857	unsigned long flags;
3858	bool cleared = false;
3859	struct dm_raid_superblock *sb;
3860	struct mddev *mddev = &rs->md;
3861	struct md_rdev *r;
3862
3863	/* RAID personalities have to provide hot add/remove methods or we need to bail out. */
3864	if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)
3865	return;
3866
3867	memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));
3868
3869	for (i = 0; i < rs->raid_disks; i++) {
3870	r = &rs->dev[i].rdev;
3871	/* HM FIXME: enhance journal device recovery processing */
3872	if (test_bit(Journal, &r->flags))
3873	continue;
3874
3875	if (test_bit(Faulty, &r->flags) &&
3876	r->meta_bdev && !read_disk_sb(rdev: r, size: r->sb_size, force_reload: true)) {
3877	DMINFO("Faulty %s device #%d has readable super block."
3878	" Attempting to revive it.",
3879	rs->raid_type->name, i);
3880
3881	/*
3882	* Faulty bit may be set, but sometimes the array can
3883	* be suspended before the personalities can respond
3884	* by removing the device from the array (i.e. calling
3885	* 'hot_remove_disk'). If they haven't yet removed
3886	* the failed device, its 'raid_disk' number will be
3887	* '>= 0' - meaning we must call this function
3888	* ourselves.
3889	*/
3890	flags = r->flags;
3891	clear_bit(nr: In_sync, addr: &r->flags); /* Mandatory for hot remove. */
3892	if (r->raid_disk >= 0) {
3893	if (mddev->pers->hot_remove_disk(mddev, r)) {
3894	/* Failed to revive this device, try next */
3895	r->flags = flags;
3896	continue;
3897	}
3898	} else
3899	r->raid_disk = r->saved_raid_disk = i;
3900
3901	clear_bit(nr: Faulty, addr: &r->flags);
3902	clear_bit(nr: WriteErrorSeen, addr: &r->flags);
3903
3904	if (mddev->pers->hot_add_disk(mddev, r)) {
3905	/* Failed to revive this device, try next */
3906	r->raid_disk = r->saved_raid_disk = -1;
3907	r->flags = flags;
3908	} else {
3909	clear_bit(nr: In_sync, addr: &r->flags);
3910	r->recovery_offset = 0;
3911	set_bit(nr: i, addr: (void *) cleared_failed_devices);
3912	cleared = true;
3913	}
3914	}
3915	}
3916
3917	/* If any failed devices could be cleared, update all sbs failed_devices bits */
3918	if (cleared) {
3919	uint64_t failed_devices[DISKS_ARRAY_ELEMS];
3920
3921	rdev_for_each(r, &rs->md) {
3922	if (test_bit(Journal, &r->flags))
3923	continue;
3924
3925	sb = page_address(r->sb_page);
3926	sb_retrieve_failed_devices(sb, failed_devices);
3927
3928	for (i = 0; i < DISKS_ARRAY_ELEMS; i++)
3929	failed_devices[i] &= ~cleared_failed_devices[i];
3930
3931	sb_update_failed_devices(sb, failed_devices);
3932	}
3933	}
3934	}
3935
3936	static int __load_dirty_region_bitmap(struct raid_set *rs)
3937	{
3938	int r = 0;
3939
3940	/* Try loading the bitmap unless "raid0", which does not have one */
3941	if (!rs_is_raid0(rs) &&
3942	!test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, addr: &rs->runtime_flags)) {
3943	r = md_bitmap_load(mddev: &rs->md);
3944	if (r)
3945	DMERR("Failed to load bitmap");
3946	}
3947
3948	return r;
3949	}
3950
3951	/* Enforce updating all superblocks */
3952	static void rs_update_sbs(struct raid_set *rs)
3953	{
3954	struct mddev *mddev = &rs->md;
3955	int ro = mddev->ro;
3956
3957	set_bit(nr: MD_SB_CHANGE_DEVS, addr: &mddev->sb_flags);
3958	mddev->ro = 0;
3959	md_update_sb(mddev, force: 1);
3960	mddev->ro = ro;
3961	}
3962
3963	/*
3964	* Reshape changes raid algorithm of @rs to new one within personality
3965	* (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3966	* disks from a raid set thus growing/shrinking it or resizes the set
3967	*
3968	* Call mddev_lock_nointr() before!
3969	*/
3970	static int rs_start_reshape(struct raid_set *rs)
3971	{
3972	int r;
3973	struct mddev *mddev = &rs->md;
3974	struct md_personality *pers = mddev->pers;
3975
3976	/* Don't allow the sync thread to work until the table gets reloaded. */
3977	set_bit(nr: MD_RECOVERY_WAIT, addr: &mddev->recovery);
3978
3979	r = rs_setup_reshape(rs);
3980	if (r)
3981	return r;
3982
3983	/*
3984	* Check any reshape constraints enforced by the personalility
3985	*
3986	* May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3987	*/
3988	r = pers->check_reshape(mddev);
3989	if (r) {
3990	rs->ti->error = "pers->check_reshape() failed";
3991	return r;
3992	}
3993
3994	/*
3995	* Personality may not provide start reshape method in which
3996	* case check_reshape above has already covered everything
3997	*/
3998	if (pers->start_reshape) {
3999	r = pers->start_reshape(mddev);
4000	if (r) {
4001	rs->ti->error = "pers->start_reshape() failed";
4002	return r;
4003	}
4004	}
4005
4006	/*
4007	* Now reshape got set up, update superblocks to
4008	* reflect the fact so that a table reload will
4009	* access proper superblock content in the ctr.
4010	*/
4011	rs_update_sbs(rs);
4012
4013	return 0;
4014	}
4015
4016	static int raid_preresume(struct dm_target *ti)
4017	{
4018	int r;
4019	struct raid_set *rs = ti->private;
4020	struct mddev *mddev = &rs->md;
4021
4022	/* This is a resume after a suspend of the set -> it's already started. */
4023	if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, addr: &rs->runtime_flags))
4024	return 0;
4025
4026	/*
4027	* The superblocks need to be updated on disk if the
4028	* array is new or new devices got added (thus zeroed
4029	* out by userspace) or __load_dirty_region_bitmap
4030	* will overwrite them in core with old data or fail.
4031	*/
4032	if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
4033	rs_update_sbs(rs);
4034
4035	/* Load the bitmap from disk unless raid0 */
4036	r = __load_dirty_region_bitmap(rs);
4037	if (r)
4038	return r;
4039
4040	/* We are extending the raid set size, adjust mddev/md_rdev sizes and set capacity. */
4041	if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
4042	mddev->array_sectors = rs->array_sectors;
4043	mddev->dev_sectors = rs->dev_sectors;
4044	rs_set_rdev_sectors(rs);
4045	rs_set_capacity(rs);
4046	}
4047
4048	/* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) or grown device size */
4049	if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
4050	(test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags) ||
4051	(rs->requested_bitmap_chunk_sectors &&
4052	mddev->bitmap_info.chunksize != to_bytes(n: rs->requested_bitmap_chunk_sectors)))) {
4053	int chunksize = to_bytes(n: rs->requested_bitmap_chunk_sectors) ?: mddev->bitmap_info.chunksize;
4054
4055	r = md_bitmap_resize(bitmap: mddev->bitmap, blocks: mddev->dev_sectors, chunksize, init: 0);
4056	if (r)
4057	DMERR("Failed to resize bitmap");
4058	}
4059
4060	/* Check for any resize/reshape on @rs and adjust/initiate */
4061	if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
4062	set_bit(nr: MD_RECOVERY_REQUESTED, addr: &mddev->recovery);
4063	mddev->resync_min = mddev->recovery_cp;
4064	if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags))
4065	mddev->resync_max_sectors = mddev->dev_sectors;
4066	}
4067
4068	/* Check for any reshape request unless new raid set */
4069	if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
4070	/* Initiate a reshape. */
4071	rs_set_rdev_sectors(rs);
4072	mddev_lock_nointr(mddev);
4073	r = rs_start_reshape(rs);
4074	mddev_unlock(mddev);
4075	if (r)
4076	DMWARN("Failed to check/start reshape, continuing without change");
4077	r = 0;
4078	}
4079
4080	return r;
4081	}
4082
4083	static void raid_resume(struct dm_target *ti)
4084	{
4085	struct raid_set *rs = ti->private;
4086	struct mddev *mddev = &rs->md;
4087
4088	if (test_and_set_bit(RT_FLAG_RS_RESUMED, addr: &rs->runtime_flags)) {
4089	/*
4090	* A secondary resume while the device is active.
4091	* Take this opportunity to check whether any failed
4092	* devices are reachable again.
4093	*/
4094	mddev_lock_nointr(mddev);
4095	attempt_restore_of_faulty_devices(rs);
4096	mddev_unlock(mddev);
4097	}
4098
4099	if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, addr: &rs->runtime_flags)) {
4100	/* Only reduce raid set size before running a disk removing reshape. */
4101	if (mddev->delta_disks < 0)
4102	rs_set_capacity(rs);
4103
4104	WARN_ON_ONCE(!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery));
4105	WARN_ON_ONCE(test_bit(MD_RECOVERY_RUNNING, &mddev->recovery));
4106	clear_bit(RT_FLAG_RS_FROZEN, addr: &rs->runtime_flags);
4107	mddev_lock_nointr(mddev);
4108	mddev->ro = 0;
4109	mddev->in_sync = 0;
4110	md_unfrozen_sync_thread(mddev);
4111	mddev_unlock_and_resume(mddev);
4112	}
4113	}
4114
4115	static struct target_type raid_target = {
4116	.name = "raid",
4117	.version = {1, 15, 1},
4118	.module = THIS_MODULE,
4119	.ctr = raid_ctr,
4120	.dtr = raid_dtr,
4121	.map = raid_map,
4122	.status = raid_status,
4123	.message = raid_message,
4124	.iterate_devices = raid_iterate_devices,
4125	.io_hints = raid_io_hints,
4126	.presuspend = raid_presuspend,
4127	.presuspend_undo = raid_presuspend_undo,
4128	.postsuspend = raid_postsuspend,
4129	.preresume = raid_preresume,
4130	.resume = raid_resume,
4131	};
4132	module_dm(raid);
4133
4134	module_param(devices_handle_discard_safely, bool, 0644);
4135	MODULE_PARM_DESC(devices_handle_discard_safely,
4136	"Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
4137
4138	MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
4139	MODULE_ALIAS("dm-raid0");
4140	MODULE_ALIAS("dm-raid1");
4141	MODULE_ALIAS("dm-raid10");
4142	MODULE_ALIAS("dm-raid4");
4143	MODULE_ALIAS("dm-raid5");
4144	MODULE_ALIAS("dm-raid6");
4145	MODULE_AUTHOR("Neil Brown <dm-devel@lists.linux.dev>");
4146	MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@lists.linux.dev>");
4147	MODULE_LICENSE("GPL");
4148