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1/*
2 * Copyright (C) 2010-2011 Neil Brown
3 * Copyright (C) 2010-2016 Red Hat, Inc. All rights reserved.
4 *
5 * This file is released under the GPL.
6 */
7
8#include <linux/slab.h>
9#include <linux/module.h>
10
11#include "md.h"
12#include "raid1.h"
13#include "raid5.h"
14#include "raid10.h"
15#include "bitmap.h"
16
17#include <linux/device-mapper.h>
18
19#define DM_MSG_PREFIX "raid"
20#define MAX_RAID_DEVICES 253 /* md-raid kernel limit */
21
22/*
23 * Minimum sectors of free reshape space per raid device
24 */
25#define MIN_FREE_RESHAPE_SPACE to_sector(4*4096)
26
27static bool devices_handle_discard_safely = false;
28
29/*
30 * The following flags are used by dm-raid.c to set up the array state.
31 * They must be cleared before md_run is called.
32 */
33#define FirstUse 10 /* rdev flag */
34
35struct raid_dev {
36 /*
37 * Two DM devices, one to hold metadata and one to hold the
38 * actual data/parity. The reason for this is to not confuse
39 * ti->len and give more flexibility in altering size and
40 * characteristics.
41 *
42 * While it is possible for this device to be associated
43 * with a different physical device than the data_dev, it
44 * is intended for it to be the same.
45 * |--------- Physical Device ---------|
46 * |- meta_dev -|------ data_dev ------|
47 */
48 struct dm_dev *meta_dev;
49 struct dm_dev *data_dev;
50 struct md_rdev rdev;
51};
52
53/*
54 * Bits for establishing rs->ctr_flags
55 *
56 * 1 = no flag value
57 * 2 = flag with value
58 */
59#define __CTR_FLAG_SYNC 0 /* 1 */ /* Not with raid0! */
60#define __CTR_FLAG_NOSYNC 1 /* 1 */ /* Not with raid0! */
61#define __CTR_FLAG_REBUILD 2 /* 2 */ /* Not with raid0! */
62#define __CTR_FLAG_DAEMON_SLEEP 3 /* 2 */ /* Not with raid0! */
63#define __CTR_FLAG_MIN_RECOVERY_RATE 4 /* 2 */ /* Not with raid0! */
64#define __CTR_FLAG_MAX_RECOVERY_RATE 5 /* 2 */ /* Not with raid0! */
65#define __CTR_FLAG_MAX_WRITE_BEHIND 6 /* 2 */ /* Only with raid1! */
66#define __CTR_FLAG_WRITE_MOSTLY 7 /* 2 */ /* Only with raid1! */
67#define __CTR_FLAG_STRIPE_CACHE 8 /* 2 */ /* Only with raid4/5/6! */
68#define __CTR_FLAG_REGION_SIZE 9 /* 2 */ /* Not with raid0! */
69#define __CTR_FLAG_RAID10_COPIES 10 /* 2 */ /* Only with raid10 */
70#define __CTR_FLAG_RAID10_FORMAT 11 /* 2 */ /* Only with raid10 */
71/* New for v1.9.0 */
72#define __CTR_FLAG_DELTA_DISKS 12 /* 2 */ /* Only with reshapable raid1/4/5/6/10! */
73#define __CTR_FLAG_DATA_OFFSET 13 /* 2 */ /* Only with reshapable raid4/5/6/10! */
74#define __CTR_FLAG_RAID10_USE_NEAR_SETS 14 /* 2 */ /* Only with raid10! */
75
76/*
77 * Flags for rs->ctr_flags field.
78 */
79#define CTR_FLAG_SYNC (1 << __CTR_FLAG_SYNC)
80#define CTR_FLAG_NOSYNC (1 << __CTR_FLAG_NOSYNC)
81#define CTR_FLAG_REBUILD (1 << __CTR_FLAG_REBUILD)
82#define CTR_FLAG_DAEMON_SLEEP (1 << __CTR_FLAG_DAEMON_SLEEP)
83#define CTR_FLAG_MIN_RECOVERY_RATE (1 << __CTR_FLAG_MIN_RECOVERY_RATE)
84#define CTR_FLAG_MAX_RECOVERY_RATE (1 << __CTR_FLAG_MAX_RECOVERY_RATE)
85#define CTR_FLAG_MAX_WRITE_BEHIND (1 << __CTR_FLAG_MAX_WRITE_BEHIND)
86#define CTR_FLAG_WRITE_MOSTLY (1 << __CTR_FLAG_WRITE_MOSTLY)
87#define CTR_FLAG_STRIPE_CACHE (1 << __CTR_FLAG_STRIPE_CACHE)
88#define CTR_FLAG_REGION_SIZE (1 << __CTR_FLAG_REGION_SIZE)
89#define CTR_FLAG_RAID10_COPIES (1 << __CTR_FLAG_RAID10_COPIES)
90#define CTR_FLAG_RAID10_FORMAT (1 << __CTR_FLAG_RAID10_FORMAT)
91#define CTR_FLAG_DELTA_DISKS (1 << __CTR_FLAG_DELTA_DISKS)
92#define CTR_FLAG_DATA_OFFSET (1 << __CTR_FLAG_DATA_OFFSET)
93#define CTR_FLAG_RAID10_USE_NEAR_SETS (1 << __CTR_FLAG_RAID10_USE_NEAR_SETS)
94
95/*
96 * Definitions of various constructor flags to
97 * be used in checks of valid / invalid flags
98 * per raid level.
99 */
100/* Define all any sync flags */
101#define CTR_FLAGS_ANY_SYNC (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)
102
103/* Define flags for options without argument (e.g. 'nosync') */
104#define CTR_FLAG_OPTIONS_NO_ARGS (CTR_FLAGS_ANY_SYNC | \
105 CTR_FLAG_RAID10_USE_NEAR_SETS)
106
107/* Define flags for options with one argument (e.g. 'delta_disks +2') */
108#define CTR_FLAG_OPTIONS_ONE_ARG (CTR_FLAG_REBUILD | \
109 CTR_FLAG_WRITE_MOSTLY | \
110 CTR_FLAG_DAEMON_SLEEP | \
111 CTR_FLAG_MIN_RECOVERY_RATE | \
112 CTR_FLAG_MAX_RECOVERY_RATE | \
113 CTR_FLAG_MAX_WRITE_BEHIND | \
114 CTR_FLAG_STRIPE_CACHE | \
115 CTR_FLAG_REGION_SIZE | \
116 CTR_FLAG_RAID10_COPIES | \
117 CTR_FLAG_RAID10_FORMAT | \
118 CTR_FLAG_DELTA_DISKS | \
119 CTR_FLAG_DATA_OFFSET)
120
121/* Valid options definitions per raid level... */
122
123/* "raid0" does only accept data offset */
124#define RAID0_VALID_FLAGS (CTR_FLAG_DATA_OFFSET)
125
126/* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */
127#define RAID1_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
128 CTR_FLAG_REBUILD | \
129 CTR_FLAG_WRITE_MOSTLY | \
130 CTR_FLAG_DAEMON_SLEEP | \
131 CTR_FLAG_MIN_RECOVERY_RATE | \
132 CTR_FLAG_MAX_RECOVERY_RATE | \
133 CTR_FLAG_MAX_WRITE_BEHIND | \
134 CTR_FLAG_REGION_SIZE | \
135 CTR_FLAG_DELTA_DISKS | \
136 CTR_FLAG_DATA_OFFSET)
137
138/* "raid10" does not accept any raid1 or stripe cache options */
139#define RAID10_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
140 CTR_FLAG_REBUILD | \
141 CTR_FLAG_DAEMON_SLEEP | \
142 CTR_FLAG_MIN_RECOVERY_RATE | \
143 CTR_FLAG_MAX_RECOVERY_RATE | \
144 CTR_FLAG_REGION_SIZE | \
145 CTR_FLAG_RAID10_COPIES | \
146 CTR_FLAG_RAID10_FORMAT | \
147 CTR_FLAG_DELTA_DISKS | \
148 CTR_FLAG_DATA_OFFSET | \
149 CTR_FLAG_RAID10_USE_NEAR_SETS)
150
151/*
152 * "raid4/5/6" do not accept any raid1 or raid10 specific options
153 *
154 * "raid6" does not accept "nosync", because it is not guaranteed
155 * that both parity and q-syndrome are being written properly with
156 * any writes
157 */
158#define RAID45_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
159 CTR_FLAG_REBUILD | \
160 CTR_FLAG_DAEMON_SLEEP | \
161 CTR_FLAG_MIN_RECOVERY_RATE | \
162 CTR_FLAG_MAX_RECOVERY_RATE | \
163 CTR_FLAG_STRIPE_CACHE | \
164 CTR_FLAG_REGION_SIZE | \
165 CTR_FLAG_DELTA_DISKS | \
166 CTR_FLAG_DATA_OFFSET)
167
168#define RAID6_VALID_FLAGS (CTR_FLAG_SYNC | \
169 CTR_FLAG_REBUILD | \
170 CTR_FLAG_DAEMON_SLEEP | \
171 CTR_FLAG_MIN_RECOVERY_RATE | \
172 CTR_FLAG_MAX_RECOVERY_RATE | \
173 CTR_FLAG_STRIPE_CACHE | \
174 CTR_FLAG_REGION_SIZE | \
175 CTR_FLAG_DELTA_DISKS | \
176 CTR_FLAG_DATA_OFFSET)
177/* ...valid options definitions per raid level */
178
179/*
180 * Flags for rs->runtime_flags field
181 * (RT_FLAG prefix meaning "runtime flag")
182 *
183 * These are all internal and used to define runtime state,
184 * e.g. to prevent another resume from preresume processing
185 * the raid set all over again.
186 */
187#define RT_FLAG_RS_PRERESUMED 0
188#define RT_FLAG_RS_RESUMED 1
189#define RT_FLAG_RS_BITMAP_LOADED 2
190#define RT_FLAG_UPDATE_SBS 3
191#define RT_FLAG_RESHAPE_RS 4
192
193/* Array elements of 64 bit needed for rebuild/failed disk bits */
194#define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
195
196/*
197 * raid set level, layout and chunk sectors backup/restore
198 */
199struct rs_layout {
200 int new_level;
201 int new_layout;
202 int new_chunk_sectors;
203};
204
205struct raid_set {
206 struct dm_target *ti;
207
208 uint32_t bitmap_loaded;
209 uint32_t stripe_cache_entries;
210 unsigned long ctr_flags;
211 unsigned long runtime_flags;
212
213 uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
214
215 int raid_disks;
216 int delta_disks;
217 int data_offset;
218 int raid10_copies;
219 int requested_bitmap_chunk_sectors;
220
221 struct mddev md;
222 struct raid_type *raid_type;
223 struct dm_target_callbacks callbacks;
224
225 struct raid_dev dev[0];
226};
227
228static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)
229{
230 struct mddev *mddev = &rs->md;
231
232 l->new_level = mddev->new_level;
233 l->new_layout = mddev->new_layout;
234 l->new_chunk_sectors = mddev->new_chunk_sectors;
235}
236
237static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)
238{
239 struct mddev *mddev = &rs->md;
240
241 mddev->new_level = l->new_level;
242 mddev->new_layout = l->new_layout;
243 mddev->new_chunk_sectors = l->new_chunk_sectors;
244}
245
246/* raid10 algorithms (i.e. formats) */
247#define ALGORITHM_RAID10_DEFAULT 0
248#define ALGORITHM_RAID10_NEAR 1
249#define ALGORITHM_RAID10_OFFSET 2
250#define ALGORITHM_RAID10_FAR 3
251
252/* Supported raid types and properties. */
253static struct raid_type {
254 const char *name; /* RAID algorithm. */
255 const char *descr; /* Descriptor text for logging. */
256 const unsigned int parity_devs; /* # of parity devices. */
257 const unsigned int minimal_devs;/* minimal # of devices in set. */
258 const unsigned int level; /* RAID level. */
259 const unsigned int algorithm; /* RAID algorithm. */
260} raid_types[] = {
261 {"raid0", "raid0 (striping)", 0, 2, 0, 0 /* NONE */},
262 {"raid1", "raid1 (mirroring)", 0, 2, 1, 0 /* NONE */},
263 {"raid10_far", "raid10 far (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_FAR},
264 {"raid10_offset", "raid10 offset (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_OFFSET},
265 {"raid10_near", "raid10 near (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_NEAR},
266 {"raid10", "raid10 (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_DEFAULT},
267 {"raid4", "raid4 (dedicated first parity disk)", 1, 2, 5, ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */
268 {"raid5_n", "raid5 (dedicated last parity disk)", 1, 2, 5, ALGORITHM_PARITY_N},
269 {"raid5_ls", "raid5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC},
270 {"raid5_rs", "raid5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC},
271 {"raid5_la", "raid5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC},
272 {"raid5_ra", "raid5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC},
273 {"raid6_zr", "raid6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART},
274 {"raid6_nr", "raid6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART},
275 {"raid6_nc", "raid6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE},
276 {"raid6_n_6", "raid6 (dedicated parity/Q n/6)", 2, 4, 6, ALGORITHM_PARITY_N_6},
277 {"raid6_ls_6", "raid6 (left symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_SYMMETRIC_6},
278 {"raid6_rs_6", "raid6 (right symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_SYMMETRIC_6},
279 {"raid6_la_6", "raid6 (left asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_ASYMMETRIC_6},
280 {"raid6_ra_6", "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_ASYMMETRIC_6}
281};
282
283/* True, if @v is in inclusive range [@min, @max] */
284static bool __within_range(long v, long min, long max)
285{
286 return v >= min && v <= max;
287}
288
289/* All table line arguments are defined here */
290static struct arg_name_flag {
291 const unsigned long flag;
292 const char *name;
293} __arg_name_flags[] = {
294 { CTR_FLAG_SYNC, "sync"},
295 { CTR_FLAG_NOSYNC, "nosync"},
296 { CTR_FLAG_REBUILD, "rebuild"},
297 { CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
298 { CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
299 { CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
300 { CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
301 { CTR_FLAG_WRITE_MOSTLY, "write_mostly"},
302 { CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
303 { CTR_FLAG_REGION_SIZE, "region_size"},
304 { CTR_FLAG_RAID10_COPIES, "raid10_copies"},
305 { CTR_FLAG_RAID10_FORMAT, "raid10_format"},
306 { CTR_FLAG_DATA_OFFSET, "data_offset"},
307 { CTR_FLAG_DELTA_DISKS, "delta_disks"},
308 { CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
309};
310
311/* Return argument name string for given @flag */
312static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
313{
314 if (hweight32(flag) == 1) {
315 struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
316
317 while (anf-- > __arg_name_flags)
318 if (flag & anf->flag)
319 return anf->name;
320
321 } else
322 DMERR("%s called with more than one flag!", __func__);
323
324 return NULL;
325}
326
327/*
328 * Bool helpers to test for various raid levels of a raid set.
329 * It's level as reported by the superblock rather than
330 * the requested raid_type passed to the constructor.
331 */
332/* Return true, if raid set in @rs is raid0 */
333static bool rs_is_raid0(struct raid_set *rs)
334{
335 return !rs->md.level;
336}
337
338/* Return true, if raid set in @rs is raid1 */
339static bool rs_is_raid1(struct raid_set *rs)
340{
341 return rs->md.level == 1;
342}
343
344/* Return true, if raid set in @rs is raid10 */
345static bool rs_is_raid10(struct raid_set *rs)
346{
347 return rs->md.level == 10;
348}
349
350/* Return true, if raid set in @rs is level 6 */
351static bool rs_is_raid6(struct raid_set *rs)
352{
353 return rs->md.level == 6;
354}
355
356/* Return true, if raid set in @rs is level 4, 5 or 6 */
357static bool rs_is_raid456(struct raid_set *rs)
358{
359 return __within_range(rs->md.level, 4, 6);
360}
361
362/* Return true, if raid set in @rs is reshapable */
363static bool __is_raid10_far(int layout);
364static bool rs_is_reshapable(struct raid_set *rs)
365{
366 return rs_is_raid456(rs) ||
367 (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
368}
369
370/* Return true, if raid set in @rs is recovering */
371static bool rs_is_recovering(struct raid_set *rs)
372{
373 return rs->md.recovery_cp < rs->dev[0].rdev.sectors;
374}
375
376/* Return true, if raid set in @rs is reshaping */
377static bool rs_is_reshaping(struct raid_set *rs)
378{
379 return rs->md.reshape_position != MaxSector;
380}
381
382/*
383 * bool helpers to test for various raid levels of a raid type @rt
384 */
385
386/* Return true, if raid type in @rt is raid0 */
387static bool rt_is_raid0(struct raid_type *rt)
388{
389 return !rt->level;
390}
391
392/* Return true, if raid type in @rt is raid1 */
393static bool rt_is_raid1(struct raid_type *rt)
394{
395 return rt->level == 1;
396}
397
398/* Return true, if raid type in @rt is raid10 */
399static bool rt_is_raid10(struct raid_type *rt)
400{
401 return rt->level == 10;
402}
403
404/* Return true, if raid type in @rt is raid4/5 */
405static bool rt_is_raid45(struct raid_type *rt)
406{
407 return __within_range(rt->level, 4, 5);
408}
409
410/* Return true, if raid type in @rt is raid6 */
411static bool rt_is_raid6(struct raid_type *rt)
412{
413 return rt->level == 6;
414}
415
416/* Return true, if raid type in @rt is raid4/5/6 */
417static bool rt_is_raid456(struct raid_type *rt)
418{
419 return __within_range(rt->level, 4, 6);
420}
421/* END: raid level bools */
422
423/* Return valid ctr flags for the raid level of @rs */
424static unsigned long __valid_flags(struct raid_set *rs)
425{
426 if (rt_is_raid0(rs->raid_type))
427 return RAID0_VALID_FLAGS;
428 else if (rt_is_raid1(rs->raid_type))
429 return RAID1_VALID_FLAGS;
430 else if (rt_is_raid10(rs->raid_type))
431 return RAID10_VALID_FLAGS;
432 else if (rt_is_raid45(rs->raid_type))
433 return RAID45_VALID_FLAGS;
434 else if (rt_is_raid6(rs->raid_type))
435 return RAID6_VALID_FLAGS;
436
437 return 0;
438}
439
440/*
441 * Check for valid flags set on @rs
442 *
443 * Has to be called after parsing of the ctr flags!
444 */
445static int rs_check_for_valid_flags(struct raid_set *rs)
446{
447 if (rs->ctr_flags & ~__valid_flags(rs)) {
448 rs->ti->error = "Invalid flags combination";
449 return -EINVAL;
450 }
451
452 return 0;
453}
454
455/* MD raid10 bit definitions and helpers */
456#define RAID10_OFFSET (1 << 16) /* stripes with data copies area adjacent on devices */
457#define RAID10_BROCKEN_USE_FAR_SETS (1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
458#define RAID10_USE_FAR_SETS (1 << 18) /* Use sets instead of whole stripe rotation */
459#define RAID10_FAR_COPIES_SHIFT 8 /* raid10 # far copies shift (2nd byte of layout) */
460
461/* Return md raid10 near copies for @layout */
462static unsigned int __raid10_near_copies(int layout)
463{
464 return layout & 0xFF;
465}
466
467/* Return md raid10 far copies for @layout */
468static unsigned int __raid10_far_copies(int layout)
469{
470 return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
471}
472
473/* Return true if md raid10 offset for @layout */
474static bool __is_raid10_offset(int layout)
475{
476 return !!(layout & RAID10_OFFSET);
477}
478
479/* Return true if md raid10 near for @layout */
480static bool __is_raid10_near(int layout)
481{
482 return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
483}
484
485/* Return true if md raid10 far for @layout */
486static bool __is_raid10_far(int layout)
487{
488 return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
489}
490
491/* Return md raid10 layout string for @layout */
492static const char *raid10_md_layout_to_format(int layout)
493{
494 /*
495 * Bit 16 stands for "offset"
496 * (i.e. adjacent stripes hold copies)
497 *
498 * Refer to MD's raid10.c for details
499 */
500 if (__is_raid10_offset(layout))
501 return "offset";
502
503 if (__raid10_near_copies(layout) > 1)
504 return "near";
505
506 WARN_ON(__raid10_far_copies(layout) < 2);
507
508 return "far";
509}
510
511/* Return md raid10 algorithm for @name */
512static int raid10_name_to_format(const char *name)
513{
514 if (!strcasecmp(name, "near"))
515 return ALGORITHM_RAID10_NEAR;
516 else if (!strcasecmp(name, "offset"))
517 return ALGORITHM_RAID10_OFFSET;
518 else if (!strcasecmp(name, "far"))
519 return ALGORITHM_RAID10_FAR;
520
521 return -EINVAL;
522}
523
524/* Return md raid10 copies for @layout */
525static unsigned int raid10_md_layout_to_copies(int layout)
526{
527 return max(__raid10_near_copies(layout), __raid10_far_copies(layout));
528}
529
530/* Return md raid10 format id for @format string */
531static int raid10_format_to_md_layout(struct raid_set *rs,
532 unsigned int algorithm,
533 unsigned int copies)
534{
535 unsigned int n = 1, f = 1, r = 0;
536
537 /*
538 * MD resilienece flaw:
539 *
540 * enabling use_far_sets for far/offset formats causes copies
541 * to be colocated on the same devs together with their origins!
542 *
543 * -> disable it for now in the definition above
544 */
545 if (algorithm == ALGORITHM_RAID10_DEFAULT ||
546 algorithm == ALGORITHM_RAID10_NEAR)
547 n = copies;
548
549 else if (algorithm == ALGORITHM_RAID10_OFFSET) {
550 f = copies;
551 r = RAID10_OFFSET;
552 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
553 r |= RAID10_USE_FAR_SETS;
554
555 } else if (algorithm == ALGORITHM_RAID10_FAR) {
556 f = copies;
557 r = !RAID10_OFFSET;
558 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
559 r |= RAID10_USE_FAR_SETS;
560
561 } else
562 return -EINVAL;
563
564 return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
565}
566/* END: MD raid10 bit definitions and helpers */
567
568/* Check for any of the raid10 algorithms */
569static bool __got_raid10(struct raid_type *rtp, const int layout)
570{
571 if (rtp->level == 10) {
572 switch (rtp->algorithm) {
573 case ALGORITHM_RAID10_DEFAULT:
574 case ALGORITHM_RAID10_NEAR:
575 return __is_raid10_near(layout);
576 case ALGORITHM_RAID10_OFFSET:
577 return __is_raid10_offset(layout);
578 case ALGORITHM_RAID10_FAR:
579 return __is_raid10_far(layout);
580 default:
581 break;
582 }
583 }
584
585 return false;
586}
587
588/* Return raid_type for @name */
589static struct raid_type *get_raid_type(const char *name)
590{
591 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
592
593 while (rtp-- > raid_types)
594 if (!strcasecmp(rtp->name, name))
595 return rtp;
596
597 return NULL;
598}
599
600/* Return raid_type for @name based derived from @level and @layout */
601static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
602{
603 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
604
605 while (rtp-- > raid_types) {
606 /* RAID10 special checks based on @layout flags/properties */
607 if (rtp->level == level &&
608 (__got_raid10(rtp, layout) || rtp->algorithm == layout))
609 return rtp;
610 }
611
612 return NULL;
613}
614
615/*
616 * Conditionally change bdev capacity of @rs
617 * in case of a disk add/remove reshape
618 */
619static void rs_set_capacity(struct raid_set *rs)
620{
621 struct mddev *mddev = &rs->md;
622 struct md_rdev *rdev;
623 struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
624
625 /*
626 * raid10 sets rdev->sector to the device size, which
627 * is unintended in case of out-of-place reshaping
628 */
629 rdev_for_each(rdev, mddev)
630 rdev->sectors = mddev->dev_sectors;
631
632 set_capacity(gendisk, mddev->array_sectors);
633 revalidate_disk(gendisk);
634}
635
636/*
637 * Set the mddev properties in @rs to the current
638 * ones retrieved from the freshest superblock
639 */
640static void rs_set_cur(struct raid_set *rs)
641{
642 struct mddev *mddev = &rs->md;
643
644 mddev->new_level = mddev->level;
645 mddev->new_layout = mddev->layout;
646 mddev->new_chunk_sectors = mddev->chunk_sectors;
647}
648
649/*
650 * Set the mddev properties in @rs to the new
651 * ones requested by the ctr
652 */
653static void rs_set_new(struct raid_set *rs)
654{
655 struct mddev *mddev = &rs->md;
656
657 mddev->level = mddev->new_level;
658 mddev->layout = mddev->new_layout;
659 mddev->chunk_sectors = mddev->new_chunk_sectors;
660 mddev->raid_disks = rs->raid_disks;
661 mddev->delta_disks = 0;
662}
663
664static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
665 unsigned int raid_devs)
666{
667 unsigned int i;
668 struct raid_set *rs;
669
670 if (raid_devs <= raid_type->parity_devs) {
671 ti->error = "Insufficient number of devices";
672 return ERR_PTR(-EINVAL);
673 }
674
675 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL);
676 if (!rs) {
677 ti->error = "Cannot allocate raid context";
678 return ERR_PTR(-ENOMEM);
679 }
680
681 mddev_init(&rs->md);
682
683 rs->raid_disks = raid_devs;
684 rs->delta_disks = 0;
685
686 rs->ti = ti;
687 rs->raid_type = raid_type;
688 rs->stripe_cache_entries = 256;
689 rs->md.raid_disks = raid_devs;
690 rs->md.level = raid_type->level;
691 rs->md.new_level = rs->md.level;
692 rs->md.layout = raid_type->algorithm;
693 rs->md.new_layout = rs->md.layout;
694 rs->md.delta_disks = 0;
695 rs->md.recovery_cp = MaxSector;
696
697 for (i = 0; i < raid_devs; i++)
698 md_rdev_init(&rs->dev[i].rdev);
699
700 /*
701 * Remaining items to be initialized by further RAID params:
702 * rs->md.persistent
703 * rs->md.external
704 * rs->md.chunk_sectors
705 * rs->md.new_chunk_sectors
706 * rs->md.dev_sectors
707 */
708
709 return rs;
710}
711
712static void raid_set_free(struct raid_set *rs)
713{
714 int i;
715
716 for (i = 0; i < rs->raid_disks; i++) {
717 if (rs->dev[i].meta_dev)
718 dm_put_device(rs->ti, rs->dev[i].meta_dev);
719 md_rdev_clear(&rs->dev[i].rdev);
720 if (rs->dev[i].data_dev)
721 dm_put_device(rs->ti, rs->dev[i].data_dev);
722 }
723
724 kfree(rs);
725}
726
727/*
728 * For every device we have two words
729 * <meta_dev>: meta device name or '-' if missing
730 * <data_dev>: data device name or '-' if missing
731 *
732 * The following are permitted:
733 * - -
734 * - <data_dev>
735 * <meta_dev> <data_dev>
736 *
737 * The following is not allowed:
738 * <meta_dev> -
739 *
740 * This code parses those words. If there is a failure,
741 * the caller must use raid_set_free() to unwind the operations.
742 */
743static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
744{
745 int i;
746 int rebuild = 0;
747 int metadata_available = 0;
748 int r = 0;
749 const char *arg;
750
751 /* Put off the number of raid devices argument to get to dev pairs */
752 arg = dm_shift_arg(as);
753 if (!arg)
754 return -EINVAL;
755
756 for (i = 0; i < rs->raid_disks; i++) {
757 rs->dev[i].rdev.raid_disk = i;
758
759 rs->dev[i].meta_dev = NULL;
760 rs->dev[i].data_dev = NULL;
761
762 /*
763 * There are no offsets, since there is a separate device
764 * for data and metadata.
765 */
766 rs->dev[i].rdev.data_offset = 0;
767 rs->dev[i].rdev.mddev = &rs->md;
768
769 arg = dm_shift_arg(as);
770 if (!arg)
771 return -EINVAL;
772
773 if (strcmp(arg, "-")) {
774 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
775 &rs->dev[i].meta_dev);
776 if (r) {
777 rs->ti->error = "RAID metadata device lookup failure";
778 return r;
779 }
780
781 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
782 if (!rs->dev[i].rdev.sb_page) {
783 rs->ti->error = "Failed to allocate superblock page";
784 return -ENOMEM;
785 }
786 }
787
788 arg = dm_shift_arg(as);
789 if (!arg)
790 return -EINVAL;
791
792 if (!strcmp(arg, "-")) {
793 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
794 (!rs->dev[i].rdev.recovery_offset)) {
795 rs->ti->error = "Drive designated for rebuild not specified";
796 return -EINVAL;
797 }
798
799 if (rs->dev[i].meta_dev) {
800 rs->ti->error = "No data device supplied with metadata device";
801 return -EINVAL;
802 }
803
804 continue;
805 }
806
807 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
808 &rs->dev[i].data_dev);
809 if (r) {
810 rs->ti->error = "RAID device lookup failure";
811 return r;
812 }
813
814 if (rs->dev[i].meta_dev) {
815 metadata_available = 1;
816 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
817 }
818 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
819 list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
820 if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
821 rebuild++;
822 }
823
824 if (metadata_available) {
825 rs->md.external = 0;
826 rs->md.persistent = 1;
827 rs->md.major_version = 2;
828 } else if (rebuild && !rs->md.recovery_cp) {
829 /*
830 * Without metadata, we will not be able to tell if the array
831 * is in-sync or not - we must assume it is not. Therefore,
832 * it is impossible to rebuild a drive.
833 *
834 * Even if there is metadata, the on-disk information may
835 * indicate that the array is not in-sync and it will then
836 * fail at that time.
837 *
838 * User could specify 'nosync' option if desperate.
839 */
840 rs->ti->error = "Unable to rebuild drive while array is not in-sync";
841 return -EINVAL;
842 }
843
844 return 0;
845}
846
847/*
848 * validate_region_size
849 * @rs
850 * @region_size: region size in sectors. If 0, pick a size (4MiB default).
851 *
852 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
853 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
854 *
855 * Returns: 0 on success, -EINVAL on failure.
856 */
857static int validate_region_size(struct raid_set *rs, unsigned long region_size)
858{
859 unsigned long min_region_size = rs->ti->len / (1 << 21);
860
861 if (rs_is_raid0(rs))
862 return 0;
863
864 if (!region_size) {
865 /*
866 * Choose a reasonable default. All figures in sectors.
867 */
868 if (min_region_size > (1 << 13)) {
869 /* If not a power of 2, make it the next power of 2 */
870 region_size = roundup_pow_of_two(min_region_size);
871 DMINFO("Choosing default region size of %lu sectors",
872 region_size);
873 } else {
874 DMINFO("Choosing default region size of 4MiB");
875 region_size = 1 << 13; /* sectors */
876 }
877 } else {
878 /*
879 * Validate user-supplied value.
880 */
881 if (region_size > rs->ti->len) {
882 rs->ti->error = "Supplied region size is too large";
883 return -EINVAL;
884 }
885
886 if (region_size < min_region_size) {
887 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
888 region_size, min_region_size);
889 rs->ti->error = "Supplied region size is too small";
890 return -EINVAL;
891 }
892
893 if (!is_power_of_2(region_size)) {
894 rs->ti->error = "Region size is not a power of 2";
895 return -EINVAL;
896 }
897
898 if (region_size < rs->md.chunk_sectors) {
899 rs->ti->error = "Region size is smaller than the chunk size";
900 return -EINVAL;
901 }
902 }
903
904 /*
905 * Convert sectors to bytes.
906 */
907 rs->md.bitmap_info.chunksize = to_bytes(region_size);
908
909 return 0;
910}
911
912/*
913 * validate_raid_redundancy
914 * @rs
915 *
916 * Determine if there are enough devices in the array that haven't
917 * failed (or are being rebuilt) to form a usable array.
918 *
919 * Returns: 0 on success, -EINVAL on failure.
920 */
921static int validate_raid_redundancy(struct raid_set *rs)
922{
923 unsigned int i, rebuild_cnt = 0;
924 unsigned int rebuilds_per_group = 0, copies;
925 unsigned int group_size, last_group_start;
926
927 for (i = 0; i < rs->md.raid_disks; i++)
928 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
929 !rs->dev[i].rdev.sb_page)
930 rebuild_cnt++;
931
932 switch (rs->raid_type->level) {
933 case 0:
934 break;
935 case 1:
936 if (rebuild_cnt >= rs->md.raid_disks)
937 goto too_many;
938 break;
939 case 4:
940 case 5:
941 case 6:
942 if (rebuild_cnt > rs->raid_type->parity_devs)
943 goto too_many;
944 break;
945 case 10:
946 copies = raid10_md_layout_to_copies(rs->md.new_layout);
947 if (rebuild_cnt < copies)
948 break;
949
950 /*
951 * It is possible to have a higher rebuild count for RAID10,
952 * as long as the failed devices occur in different mirror
953 * groups (i.e. different stripes).
954 *
955 * When checking "near" format, make sure no adjacent devices
956 * have failed beyond what can be handled. In addition to the
957 * simple case where the number of devices is a multiple of the
958 * number of copies, we must also handle cases where the number
959 * of devices is not a multiple of the number of copies.
960 * E.g. dev1 dev2 dev3 dev4 dev5
961 * A A B B C
962 * C D D E E
963 */
964 if (__is_raid10_near(rs->md.new_layout)) {
965 for (i = 0; i < rs->md.raid_disks; i++) {
966 if (!(i % copies))
967 rebuilds_per_group = 0;
968 if ((!rs->dev[i].rdev.sb_page ||
969 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
970 (++rebuilds_per_group >= copies))
971 goto too_many;
972 }
973 break;
974 }
975
976 /*
977 * When checking "far" and "offset" formats, we need to ensure
978 * that the device that holds its copy is not also dead or
979 * being rebuilt. (Note that "far" and "offset" formats only
980 * support two copies right now. These formats also only ever
981 * use the 'use_far_sets' variant.)
982 *
983 * This check is somewhat complicated by the need to account
984 * for arrays that are not a multiple of (far) copies. This
985 * results in the need to treat the last (potentially larger)
986 * set differently.
987 */
988 group_size = (rs->md.raid_disks / copies);
989 last_group_start = (rs->md.raid_disks / group_size) - 1;
990 last_group_start *= group_size;
991 for (i = 0; i < rs->md.raid_disks; i++) {
992 if (!(i % copies) && !(i > last_group_start))
993 rebuilds_per_group = 0;
994 if ((!rs->dev[i].rdev.sb_page ||
995 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
996 (++rebuilds_per_group >= copies))
997 goto too_many;
998 }
999 break;
1000 default:
1001 if (rebuild_cnt)
1002 return -EINVAL;
1003 }
1004
1005 return 0;
1006
1007too_many:
1008 return -EINVAL;
1009}
1010
1011/*
1012 * Possible arguments are...
1013 * <chunk_size> [optional_args]
1014 *
1015 * Argument definitions
1016 * <chunk_size> The number of sectors per disk that
1017 * will form the "stripe"
1018 * [[no]sync] Force or prevent recovery of the
1019 * entire array
1020 * [rebuild <idx>] Rebuild the drive indicated by the index
1021 * [daemon_sleep <ms>] Time between bitmap daemon work to
1022 * clear bits
1023 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1024 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1025 * [write_mostly <idx>] Indicate a write mostly drive via index
1026 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
1027 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs
1028 * [region_size <sectors>] Defines granularity of bitmap
1029 *
1030 * RAID10-only options:
1031 * [raid10_copies <# copies>] Number of copies. (Default: 2)
1032 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
1033 */
1034static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
1035 unsigned int num_raid_params)
1036{
1037 int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
1038 unsigned int raid10_copies = 2;
1039 unsigned int i, write_mostly = 0;
1040 unsigned int region_size = 0;
1041 sector_t max_io_len;
1042 const char *arg, *key;
1043 struct raid_dev *rd;
1044 struct raid_type *rt = rs->raid_type;
1045
1046 arg = dm_shift_arg(as);
1047 num_raid_params--; /* Account for chunk_size argument */
1048
1049 if (kstrtoint(arg, 10, &value) < 0) {
1050 rs->ti->error = "Bad numerical argument given for chunk_size";
1051 return -EINVAL;
1052 }
1053
1054 /*
1055 * First, parse the in-order required arguments
1056 * "chunk_size" is the only argument of this type.
1057 */
1058 if (rt_is_raid1(rt)) {
1059 if (value)
1060 DMERR("Ignoring chunk size parameter for RAID 1");
1061 value = 0;
1062 } else if (!is_power_of_2(value)) {
1063 rs->ti->error = "Chunk size must be a power of 2";
1064 return -EINVAL;
1065 } else if (value < 8) {
1066 rs->ti->error = "Chunk size value is too small";
1067 return -EINVAL;
1068 }
1069
1070 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1071
1072 /*
1073 * We set each individual device as In_sync with a completed
1074 * 'recovery_offset'. If there has been a device failure or
1075 * replacement then one of the following cases applies:
1076 *
1077 * 1) User specifies 'rebuild'.
1078 * - Device is reset when param is read.
1079 * 2) A new device is supplied.
1080 * - No matching superblock found, resets device.
1081 * 3) Device failure was transient and returns on reload.
1082 * - Failure noticed, resets device for bitmap replay.
1083 * 4) Device hadn't completed recovery after previous failure.
1084 * - Superblock is read and overrides recovery_offset.
1085 *
1086 * What is found in the superblocks of the devices is always
1087 * authoritative, unless 'rebuild' or '[no]sync' was specified.
1088 */
1089 for (i = 0; i < rs->raid_disks; i++) {
1090 set_bit(In_sync, &rs->dev[i].rdev.flags);
1091 rs->dev[i].rdev.recovery_offset = MaxSector;
1092 }
1093
1094 /*
1095 * Second, parse the unordered optional arguments
1096 */
1097 for (i = 0; i < num_raid_params; i++) {
1098 key = dm_shift_arg(as);
1099 if (!key) {
1100 rs->ti->error = "Not enough raid parameters given";
1101 return -EINVAL;
1102 }
1103
1104 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1105 if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1106 rs->ti->error = "Only one 'nosync' argument allowed";
1107 return -EINVAL;
1108 }
1109 continue;
1110 }
1111 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1112 if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1113 rs->ti->error = "Only one 'sync' argument allowed";
1114 return -EINVAL;
1115 }
1116 continue;
1117 }
1118 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1119 if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1120 rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1121 return -EINVAL;
1122 }
1123 continue;
1124 }
1125
1126 arg = dm_shift_arg(as);
1127 i++; /* Account for the argument pairs */
1128 if (!arg) {
1129 rs->ti->error = "Wrong number of raid parameters given";
1130 return -EINVAL;
1131 }
1132
1133 /*
1134 * Parameters that take a string value are checked here.
1135 */
1136
1137 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1138 if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1139 rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1140 return -EINVAL;
1141 }
1142 if (!rt_is_raid10(rt)) {
1143 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1144 return -EINVAL;
1145 }
1146 raid10_format = raid10_name_to_format(arg);
1147 if (raid10_format < 0) {
1148 rs->ti->error = "Invalid 'raid10_format' value given";
1149 return raid10_format;
1150 }
1151 continue;
1152 }
1153
1154 if (kstrtoint(arg, 10, &value) < 0) {
1155 rs->ti->error = "Bad numerical argument given in raid params";
1156 return -EINVAL;
1157 }
1158
1159 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1160 /*
1161 * "rebuild" is being passed in by userspace to provide
1162 * indexes of replaced devices and to set up additional
1163 * devices on raid level takeover.
1164 */
1165 if (!__within_range(value, 0, rs->raid_disks - 1)) {
1166 rs->ti->error = "Invalid rebuild index given";
1167 return -EINVAL;
1168 }
1169
1170 if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1171 rs->ti->error = "rebuild for this index already given";
1172 return -EINVAL;
1173 }
1174
1175 rd = rs->dev + value;
1176 clear_bit(In_sync, &rd->rdev.flags);
1177 clear_bit(Faulty, &rd->rdev.flags);
1178 rd->rdev.recovery_offset = 0;
1179 set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1180 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1181 if (!rt_is_raid1(rt)) {
1182 rs->ti->error = "write_mostly option is only valid for RAID1";
1183 return -EINVAL;
1184 }
1185
1186 if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1187 rs->ti->error = "Invalid write_mostly index given";
1188 return -EINVAL;
1189 }
1190
1191 write_mostly++;
1192 set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1193 set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1194 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1195 if (!rt_is_raid1(rt)) {
1196 rs->ti->error = "max_write_behind option is only valid for RAID1";
1197 return -EINVAL;
1198 }
1199
1200 if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1201 rs->ti->error = "Only one max_write_behind argument pair allowed";
1202 return -EINVAL;
1203 }
1204
1205 /*
1206 * In device-mapper, we specify things in sectors, but
1207 * MD records this value in kB
1208 */
1209 value /= 2;
1210 if (value > COUNTER_MAX) {
1211 rs->ti->error = "Max write-behind limit out of range";
1212 return -EINVAL;
1213 }
1214
1215 rs->md.bitmap_info.max_write_behind = value;
1216 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1217 if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1218 rs->ti->error = "Only one daemon_sleep argument pair allowed";
1219 return -EINVAL;
1220 }
1221 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
1222 rs->ti->error = "daemon sleep period out of range";
1223 return -EINVAL;
1224 }
1225 rs->md.bitmap_info.daemon_sleep = value;
1226 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1227 /* Userspace passes new data_offset after having extended the the data image LV */
1228 if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1229 rs->ti->error = "Only one data_offset argument pair allowed";
1230 return -EINVAL;
1231 }
1232 /* Ensure sensible data offset */
1233 if (value < 0 ||
1234 (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {
1235 rs->ti->error = "Bogus data_offset value";
1236 return -EINVAL;
1237 }
1238 rs->data_offset = value;
1239 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1240 /* Define the +/-# of disks to add to/remove from the given raid set */
1241 if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1242 rs->ti->error = "Only one delta_disks argument pair allowed";
1243 return -EINVAL;
1244 }
1245 /* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1246 if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1247 rs->ti->error = "Too many delta_disk requested";
1248 return -EINVAL;
1249 }
1250
1251 rs->delta_disks = value;
1252 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1253 if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1254 rs->ti->error = "Only one stripe_cache argument pair allowed";
1255 return -EINVAL;
1256 }
1257
1258 if (!rt_is_raid456(rt)) {
1259 rs->ti->error = "Inappropriate argument: stripe_cache";
1260 return -EINVAL;
1261 }
1262
1263 rs->stripe_cache_entries = value;
1264 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1265 if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1266 rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1267 return -EINVAL;
1268 }
1269 if (value > INT_MAX) {
1270 rs->ti->error = "min_recovery_rate out of range";
1271 return -EINVAL;
1272 }
1273 rs->md.sync_speed_min = (int)value;
1274 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1275 if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
1276 rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1277 return -EINVAL;
1278 }
1279 if (value > INT_MAX) {
1280 rs->ti->error = "max_recovery_rate out of range";
1281 return -EINVAL;
1282 }
1283 rs->md.sync_speed_max = (int)value;
1284 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1285 if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1286 rs->ti->error = "Only one region_size argument pair allowed";
1287 return -EINVAL;
1288 }
1289
1290 region_size = value;
1291 rs->requested_bitmap_chunk_sectors = value;
1292 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1293 if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1294 rs->ti->error = "Only one raid10_copies argument pair allowed";
1295 return -EINVAL;
1296 }
1297
1298 if (!__within_range(value, 2, rs->md.raid_disks)) {
1299 rs->ti->error = "Bad value for 'raid10_copies'";
1300 return -EINVAL;
1301 }
1302
1303 raid10_copies = value;
1304 } else {
1305 DMERR("Unable to parse RAID parameter: %s", key);
1306 rs->ti->error = "Unable to parse RAID parameter";
1307 return -EINVAL;
1308 }
1309 }
1310
1311 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1312 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1313 rs->ti->error = "sync and nosync are mutually exclusive";
1314 return -EINVAL;
1315 }
1316
1317 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
1318 (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
1319 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
1320 rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
1321 return -EINVAL;
1322 }
1323
1324 if (write_mostly >= rs->md.raid_disks) {
1325 rs->ti->error = "Can't set all raid1 devices to write_mostly";
1326 return -EINVAL;
1327 }
1328
1329 if (validate_region_size(rs, region_size))
1330 return -EINVAL;
1331
1332 if (rs->md.chunk_sectors)
1333 max_io_len = rs->md.chunk_sectors;
1334 else
1335 max_io_len = region_size;
1336
1337 if (dm_set_target_max_io_len(rs->ti, max_io_len))
1338 return -EINVAL;
1339
1340 if (rt_is_raid10(rt)) {
1341 if (raid10_copies > rs->md.raid_disks) {
1342 rs->ti->error = "Not enough devices to satisfy specification";
1343 return -EINVAL;
1344 }
1345
1346 rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1347 if (rs->md.new_layout < 0) {
1348 rs->ti->error = "Error getting raid10 format";
1349 return rs->md.new_layout;
1350 }
1351
1352 rt = get_raid_type_by_ll(10, rs->md.new_layout);
1353 if (!rt) {
1354 rs->ti->error = "Failed to recognize new raid10 layout";
1355 return -EINVAL;
1356 }
1357
1358 if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1359 rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1360 test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1361 rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1362 return -EINVAL;
1363 }
1364 }
1365
1366 rs->raid10_copies = raid10_copies;
1367
1368 /* Assume there are no metadata devices until the drives are parsed */
1369 rs->md.persistent = 0;
1370 rs->md.external = 1;
1371
1372 /* Check, if any invalid ctr arguments have been passed in for the raid level */
1373 return rs_check_for_valid_flags(rs);
1374}
1375
1376/* Set raid4/5/6 cache size */
1377static int rs_set_raid456_stripe_cache(struct raid_set *rs)
1378{
1379 int r;
1380 struct r5conf *conf;
1381 struct mddev *mddev = &rs->md;
1382 uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
1383 uint32_t nr_stripes = rs->stripe_cache_entries;
1384
1385 if (!rt_is_raid456(rs->raid_type)) {
1386 rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
1387 return -EINVAL;
1388 }
1389
1390 if (nr_stripes < min_stripes) {
1391 DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
1392 nr_stripes, min_stripes);
1393 nr_stripes = min_stripes;
1394 }
1395
1396 conf = mddev->private;
1397 if (!conf) {
1398 rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
1399 return -EINVAL;
1400 }
1401
1402 /* Try setting number of stripes in raid456 stripe cache */
1403 if (conf->min_nr_stripes != nr_stripes) {
1404 r = raid5_set_cache_size(mddev, nr_stripes);
1405 if (r) {
1406 rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
1407 return r;
1408 }
1409
1410 DMINFO("%u stripe cache entries", nr_stripes);
1411 }
1412
1413 return 0;
1414}
1415
1416/* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1417static unsigned int mddev_data_stripes(struct raid_set *rs)
1418{
1419 return rs->md.raid_disks - rs->raid_type->parity_devs;
1420}
1421
1422/* Return # of data stripes of @rs (i.e. as of ctr) */
1423static unsigned int rs_data_stripes(struct raid_set *rs)
1424{
1425 return rs->raid_disks - rs->raid_type->parity_devs;
1426}
1427
1428/* Calculate the sectors per device and per array used for @rs */
1429static int rs_set_dev_and_array_sectors(struct raid_set *rs, bool use_mddev)
1430{
1431 int delta_disks;
1432 unsigned int data_stripes;
1433 struct mddev *mddev = &rs->md;
1434 struct md_rdev *rdev;
1435 sector_t array_sectors = rs->ti->len, dev_sectors = rs->ti->len;
1436
1437 if (use_mddev) {
1438 delta_disks = mddev->delta_disks;
1439 data_stripes = mddev_data_stripes(rs);
1440 } else {
1441 delta_disks = rs->delta_disks;
1442 data_stripes = rs_data_stripes(rs);
1443 }
1444
1445 /* Special raid1 case w/o delta_disks support (yet) */
1446 if (rt_is_raid1(rs->raid_type))
1447 ;
1448 else if (rt_is_raid10(rs->raid_type)) {
1449 if (rs->raid10_copies < 2 ||
1450 delta_disks < 0) {
1451 rs->ti->error = "Bogus raid10 data copies or delta disks";
1452 return -EINVAL;
1453 }
1454
1455 dev_sectors *= rs->raid10_copies;
1456 if (sector_div(dev_sectors, data_stripes))
1457 goto bad;
1458
1459 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1460 if (sector_div(array_sectors, rs->raid10_copies))
1461 goto bad;
1462
1463 } else if (sector_div(dev_sectors, data_stripes))
1464 goto bad;
1465
1466 else
1467 /* Striped layouts */
1468 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1469
1470 rdev_for_each(rdev, mddev)
1471 rdev->sectors = dev_sectors;
1472
1473 mddev->array_sectors = array_sectors;
1474 mddev->dev_sectors = dev_sectors;
1475
1476 return 0;
1477bad:
1478 rs->ti->error = "Target length not divisible by number of data devices";
1479 return -EINVAL;
1480}
1481
1482/* Setup recovery on @rs */
1483static void __rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1484{
1485 /* raid0 does not recover */
1486 if (rs_is_raid0(rs))
1487 rs->md.recovery_cp = MaxSector;
1488 /*
1489 * A raid6 set has to be recovered either
1490 * completely or for the grown part to
1491 * ensure proper parity and Q-Syndrome
1492 */
1493 else if (rs_is_raid6(rs))
1494 rs->md.recovery_cp = dev_sectors;
1495 /*
1496 * Other raid set types may skip recovery
1497 * depending on the 'nosync' flag.
1498 */
1499 else
1500 rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
1501 ? MaxSector : dev_sectors;
1502}
1503
1504/* Setup recovery on @rs based on raid type, device size and 'nosync' flag */
1505static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1506{
1507 if (!dev_sectors)
1508 /* New raid set or 'sync' flag provided */
1509 __rs_setup_recovery(rs, 0);
1510 else if (dev_sectors == MaxSector)
1511 /* Prevent recovery */
1512 __rs_setup_recovery(rs, MaxSector);
1513 else if (rs->dev[0].rdev.sectors < dev_sectors)
1514 /* Grown raid set */
1515 __rs_setup_recovery(rs, rs->dev[0].rdev.sectors);
1516 else
1517 __rs_setup_recovery(rs, MaxSector);
1518}
1519
1520static void do_table_event(struct work_struct *ws)
1521{
1522 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1523
1524 smp_rmb(); /* Make sure we access most actual mddev properties */
1525 if (!rs_is_reshaping(rs))
1526 rs_set_capacity(rs);
1527 dm_table_event(rs->ti->table);
1528}
1529
1530static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
1531{
1532 struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
1533
1534 return mddev_congested(&rs->md, bits);
1535}
1536
1537/*
1538 * Make sure a valid takover (level switch) is being requested on @rs
1539 *
1540 * Conversions of raid sets from one MD personality to another
1541 * have to conform to restrictions which are enforced here.
1542 */
1543static int rs_check_takeover(struct raid_set *rs)
1544{
1545 struct mddev *mddev = &rs->md;
1546 unsigned int near_copies;
1547
1548 if (rs->md.degraded) {
1549 rs->ti->error = "Can't takeover degraded raid set";
1550 return -EPERM;
1551 }
1552
1553 if (rs_is_reshaping(rs)) {
1554 rs->ti->error = "Can't takeover reshaping raid set";
1555 return -EPERM;
1556 }
1557
1558 switch (mddev->level) {
1559 case 0:
1560 /* raid0 -> raid1/5 with one disk */
1561 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1562 mddev->raid_disks == 1)
1563 return 0;
1564
1565 /* raid0 -> raid10 */
1566 if (mddev->new_level == 10 &&
1567 !(rs->raid_disks % mddev->raid_disks))
1568 return 0;
1569
1570 /* raid0 with multiple disks -> raid4/5/6 */
1571 if (__within_range(mddev->new_level, 4, 6) &&
1572 mddev->new_layout == ALGORITHM_PARITY_N &&
1573 mddev->raid_disks > 1)
1574 return 0;
1575
1576 break;
1577
1578 case 10:
1579 /* Can't takeover raid10_offset! */
1580 if (__is_raid10_offset(mddev->layout))
1581 break;
1582
1583 near_copies = __raid10_near_copies(mddev->layout);
1584
1585 /* raid10* -> raid0 */
1586 if (mddev->new_level == 0) {
1587 /* Can takeover raid10_near with raid disks divisable by data copies! */
1588 if (near_copies > 1 &&
1589 !(mddev->raid_disks % near_copies)) {
1590 mddev->raid_disks /= near_copies;
1591 mddev->delta_disks = mddev->raid_disks;
1592 return 0;
1593 }
1594
1595 /* Can takeover raid10_far */
1596 if (near_copies == 1 &&
1597 __raid10_far_copies(mddev->layout) > 1)
1598 return 0;
1599
1600 break;
1601 }
1602
1603 /* raid10_{near,far} -> raid1 */
1604 if (mddev->new_level == 1 &&
1605 max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1606 return 0;
1607
1608 /* raid10_{near,far} with 2 disks -> raid4/5 */
1609 if (__within_range(mddev->new_level, 4, 5) &&
1610 mddev->raid_disks == 2)
1611 return 0;
1612 break;
1613
1614 case 1:
1615 /* raid1 with 2 disks -> raid4/5 */
1616 if (__within_range(mddev->new_level, 4, 5) &&
1617 mddev->raid_disks == 2) {
1618 mddev->degraded = 1;
1619 return 0;
1620 }
1621
1622 /* raid1 -> raid0 */
1623 if (mddev->new_level == 0 &&
1624 mddev->raid_disks == 1)
1625 return 0;
1626
1627 /* raid1 -> raid10 */
1628 if (mddev->new_level == 10)
1629 return 0;
1630 break;
1631
1632 case 4:
1633 /* raid4 -> raid0 */
1634 if (mddev->new_level == 0)
1635 return 0;
1636
1637 /* raid4 -> raid1/5 with 2 disks */
1638 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1639 mddev->raid_disks == 2)
1640 return 0;
1641
1642 /* raid4 -> raid5/6 with parity N */
1643 if (__within_range(mddev->new_level, 5, 6) &&
1644 mddev->layout == ALGORITHM_PARITY_N)
1645 return 0;
1646 break;
1647
1648 case 5:
1649 /* raid5 with parity N -> raid0 */
1650 if (mddev->new_level == 0 &&
1651 mddev->layout == ALGORITHM_PARITY_N)
1652 return 0;
1653
1654 /* raid5 with parity N -> raid4 */
1655 if (mddev->new_level == 4 &&
1656 mddev->layout == ALGORITHM_PARITY_N)
1657 return 0;
1658
1659 /* raid5 with 2 disks -> raid1/4/10 */
1660 if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1661 mddev->raid_disks == 2)
1662 return 0;
1663
1664 /* raid5_* -> raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
1665 if (mddev->new_level == 6 &&
1666 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1667 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1668 return 0;
1669 break;
1670
1671 case 6:
1672 /* raid6 with parity N -> raid0 */
1673 if (mddev->new_level == 0 &&
1674 mddev->layout == ALGORITHM_PARITY_N)
1675 return 0;
1676
1677 /* raid6 with parity N -> raid4 */
1678 if (mddev->new_level == 4 &&
1679 mddev->layout == ALGORITHM_PARITY_N)
1680 return 0;
1681
1682 /* raid6_*_n with Q-Syndrome N -> raid5_* */
1683 if (mddev->new_level == 5 &&
1684 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1685 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1686 return 0;
1687
1688 default:
1689 break;
1690 }
1691
1692 rs->ti->error = "takeover not possible";
1693 return -EINVAL;
1694}
1695
1696/* True if @rs requested to be taken over */
1697static bool rs_takeover_requested(struct raid_set *rs)
1698{
1699 return rs->md.new_level != rs->md.level;
1700}
1701
1702/* True if @rs is requested to reshape by ctr */
1703static bool rs_reshape_requested(struct raid_set *rs)
1704{
1705 bool change;
1706 struct mddev *mddev = &rs->md;
1707
1708 if (rs_takeover_requested(rs))
1709 return false;
1710
1711 if (!mddev->level)
1712 return false;
1713
1714 change = mddev->new_layout != mddev->layout ||
1715 mddev->new_chunk_sectors != mddev->chunk_sectors ||
1716 rs->delta_disks;
1717
1718 /* Historical case to support raid1 reshape without delta disks */
1719 if (mddev->level == 1) {
1720 if (rs->delta_disks)
1721 return !!rs->delta_disks;
1722
1723 return !change &&
1724 mddev->raid_disks != rs->raid_disks;
1725 }
1726
1727 if (mddev->level == 10)
1728 return change &&
1729 !__is_raid10_far(mddev->new_layout) &&
1730 rs->delta_disks >= 0;
1731
1732 return change;
1733}
1734
1735/* Features */
1736#define FEATURE_FLAG_SUPPORTS_V190 0x1 /* Supports extended superblock */
1737
1738/* State flags for sb->flags */
1739#define SB_FLAG_RESHAPE_ACTIVE 0x1
1740#define SB_FLAG_RESHAPE_BACKWARDS 0x2
1741
1742/*
1743 * This structure is never routinely used by userspace, unlike md superblocks.
1744 * Devices with this superblock should only ever be accessed via device-mapper.
1745 */
1746#define DM_RAID_MAGIC 0x64526D44
1747struct dm_raid_superblock {
1748 __le32 magic; /* "DmRd" */
1749 __le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1750
1751 __le32 num_devices; /* Number of devices in this raid set. (Max 64) */
1752 __le32 array_position; /* The position of this drive in the raid set */
1753
1754 __le64 events; /* Incremented by md when superblock updated */
1755 __le64 failed_devices; /* Pre 1.9.0 part of bit field of devices to */
1756 /* indicate failures (see extension below) */
1757
1758 /*
1759 * This offset tracks the progress of the repair or replacement of
1760 * an individual drive.
1761 */
1762 __le64 disk_recovery_offset;
1763
1764 /*
1765 * This offset tracks the progress of the initial raid set
1766 * synchronisation/parity calculation.
1767 */
1768 __le64 array_resync_offset;
1769
1770 /*
1771 * raid characteristics
1772 */
1773 __le32 level;
1774 __le32 layout;
1775 __le32 stripe_sectors;
1776
1777 /********************************************************************
1778 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1779 *
1780 * FEATURE_FLAG_SUPPORTS_V190 in the features member indicates that those exist
1781 */
1782
1783 __le32 flags; /* Flags defining array states for reshaping */
1784
1785 /*
1786 * This offset tracks the progress of a raid
1787 * set reshape in order to be able to restart it
1788 */
1789 __le64 reshape_position;
1790
1791 /*
1792 * These define the properties of the array in case of an interrupted reshape
1793 */
1794 __le32 new_level;
1795 __le32 new_layout;
1796 __le32 new_stripe_sectors;
1797 __le32 delta_disks;
1798
1799 __le64 array_sectors; /* Array size in sectors */
1800
1801 /*
1802 * Sector offsets to data on devices (reshaping).
1803 * Needed to support out of place reshaping, thus
1804 * not writing over any stripes whilst converting
1805 * them from old to new layout
1806 */
1807 __le64 data_offset;
1808 __le64 new_data_offset;
1809
1810 __le64 sectors; /* Used device size in sectors */
1811
1812 /*
1813 * Additonal Bit field of devices indicating failures to support
1814 * up to 256 devices with the 1.9.0 on-disk metadata format
1815 */
1816 __le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
1817
1818 __le32 incompat_features; /* Used to indicate any incompatible features */
1819
1820 /* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
1821} __packed;
1822
1823/*
1824 * Check for reshape constraints on raid set @rs:
1825 *
1826 * - reshape function non-existent
1827 * - degraded set
1828 * - ongoing recovery
1829 * - ongoing reshape
1830 *
1831 * Returns 0 if none or -EPERM if given constraint
1832 * and error message reference in @errmsg
1833 */
1834static int rs_check_reshape(struct raid_set *rs)
1835{
1836 struct mddev *mddev = &rs->md;
1837
1838 if (!mddev->pers || !mddev->pers->check_reshape)
1839 rs->ti->error = "Reshape not supported";
1840 else if (mddev->degraded)
1841 rs->ti->error = "Can't reshape degraded raid set";
1842 else if (rs_is_recovering(rs))
1843 rs->ti->error = "Convert request on recovering raid set prohibited";
1844 else if (rs_is_reshaping(rs))
1845 rs->ti->error = "raid set already reshaping!";
1846 else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
1847 rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
1848 else
1849 return 0;
1850
1851 return -EPERM;
1852}
1853
1854static int read_disk_sb(struct md_rdev *rdev, int size)
1855{
1856 BUG_ON(!rdev->sb_page);
1857
1858 if (rdev->sb_loaded)
1859 return 0;
1860
1861 if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, true)) {
1862 DMERR("Failed to read superblock of device at position %d",
1863 rdev->raid_disk);
1864 md_error(rdev->mddev, rdev);
1865 return -EINVAL;
1866 }
1867
1868 rdev->sb_loaded = 1;
1869
1870 return 0;
1871}
1872
1873static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1874{
1875 failed_devices[0] = le64_to_cpu(sb->failed_devices);
1876 memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
1877
1878 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
1879 int i = ARRAY_SIZE(sb->extended_failed_devices);
1880
1881 while (i--)
1882 failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
1883 }
1884}
1885
1886static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1887{
1888 int i = ARRAY_SIZE(sb->extended_failed_devices);
1889
1890 sb->failed_devices = cpu_to_le64(failed_devices[0]);
1891 while (i--)
1892 sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
1893}
1894
1895/*
1896 * Synchronize the superblock members with the raid set properties
1897 *
1898 * All superblock data is little endian.
1899 */
1900static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
1901{
1902 bool update_failed_devices = false;
1903 unsigned int i;
1904 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
1905 struct dm_raid_superblock *sb;
1906 struct raid_set *rs = container_of(mddev, struct raid_set, md);
1907
1908 /* No metadata device, no superblock */
1909 if (!rdev->meta_bdev)
1910 return;
1911
1912 BUG_ON(!rdev->sb_page);
1913
1914 sb = page_address(rdev->sb_page);
1915
1916 sb_retrieve_failed_devices(sb, failed_devices);
1917
1918 for (i = 0; i < rs->raid_disks; i++)
1919 if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
1920 update_failed_devices = true;
1921 set_bit(i, (void *) failed_devices);
1922 }
1923
1924 if (update_failed_devices)
1925 sb_update_failed_devices(sb, failed_devices);
1926
1927 sb->magic = cpu_to_le32(DM_RAID_MAGIC);
1928 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
1929
1930 sb->num_devices = cpu_to_le32(mddev->raid_disks);
1931 sb->array_position = cpu_to_le32(rdev->raid_disk);
1932
1933 sb->events = cpu_to_le64(mddev->events);
1934
1935 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
1936 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
1937
1938 sb->level = cpu_to_le32(mddev->level);
1939 sb->layout = cpu_to_le32(mddev->layout);
1940 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
1941
1942 sb->new_level = cpu_to_le32(mddev->new_level);
1943 sb->new_layout = cpu_to_le32(mddev->new_layout);
1944 sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
1945
1946 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1947
1948 smp_rmb(); /* Make sure we access most recent reshape position */
1949 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1950 if (le64_to_cpu(sb->reshape_position) != MaxSector) {
1951 /* Flag ongoing reshape */
1952 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
1953
1954 if (mddev->delta_disks < 0 || mddev->reshape_backwards)
1955 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
1956 } else {
1957 /* Clear reshape flags */
1958 sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
1959 }
1960
1961 sb->array_sectors = cpu_to_le64(mddev->array_sectors);
1962 sb->data_offset = cpu_to_le64(rdev->data_offset);
1963 sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
1964 sb->sectors = cpu_to_le64(rdev->sectors);
1965 sb->incompat_features = cpu_to_le32(0);
1966
1967 /* Zero out the rest of the payload after the size of the superblock */
1968 memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
1969}
1970
1971/*
1972 * super_load
1973 *
1974 * This function creates a superblock if one is not found on the device
1975 * and will decide which superblock to use if there's a choice.
1976 *
1977 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
1978 */
1979static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
1980{
1981 int r;
1982 struct dm_raid_superblock *sb;
1983 struct dm_raid_superblock *refsb;
1984 uint64_t events_sb, events_refsb;
1985
1986 rdev->sb_start = 0;
1987 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
1988 if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) {
1989 DMERR("superblock size of a logical block is no longer valid");
1990 return -EINVAL;
1991 }
1992
1993 r = read_disk_sb(rdev, rdev->sb_size);
1994 if (r)
1995 return r;
1996
1997 sb = page_address(rdev->sb_page);
1998
1999 /*
2000 * Two cases that we want to write new superblocks and rebuild:
2001 * 1) New device (no matching magic number)
2002 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
2003 */
2004 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
2005 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
2006 super_sync(rdev->mddev, rdev);
2007
2008 set_bit(FirstUse, &rdev->flags);
2009 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2010
2011 /* Force writing of superblocks to disk */
2012 set_bit(MD_SB_CHANGE_DEVS, &rdev->mddev->sb_flags);
2013
2014 /* Any superblock is better than none, choose that if given */
2015 return refdev ? 0 : 1;
2016 }
2017
2018 if (!refdev)
2019 return 1;
2020
2021 events_sb = le64_to_cpu(sb->events);
2022
2023 refsb = page_address(refdev->sb_page);
2024 events_refsb = le64_to_cpu(refsb->events);
2025
2026 return (events_sb > events_refsb) ? 1 : 0;
2027}
2028
2029static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
2030{
2031 int role;
2032 unsigned int d;
2033 struct mddev *mddev = &rs->md;
2034 uint64_t events_sb;
2035 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2036 struct dm_raid_superblock *sb;
2037 uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
2038 struct md_rdev *r;
2039 struct dm_raid_superblock *sb2;
2040
2041 sb = page_address(rdev->sb_page);
2042 events_sb = le64_to_cpu(sb->events);
2043
2044 /*
2045 * Initialise to 1 if this is a new superblock.
2046 */
2047 mddev->events = events_sb ? : 1;
2048
2049 mddev->reshape_position = MaxSector;
2050
2051 mddev->raid_disks = le32_to_cpu(sb->num_devices);
2052 mddev->level = le32_to_cpu(sb->level);
2053 mddev->layout = le32_to_cpu(sb->layout);
2054 mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
2055
2056 /*
2057 * Reshaping is supported, e.g. reshape_position is valid
2058 * in superblock and superblock content is authoritative.
2059 */
2060 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2061 /* Superblock is authoritative wrt given raid set layout! */
2062 mddev->new_level = le32_to_cpu(sb->new_level);
2063 mddev->new_layout = le32_to_cpu(sb->new_layout);
2064 mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
2065 mddev->delta_disks = le32_to_cpu(sb->delta_disks);
2066 mddev->array_sectors = le64_to_cpu(sb->array_sectors);
2067
2068 /* raid was reshaping and got interrupted */
2069 if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2070 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2071 DMERR("Reshape requested but raid set is still reshaping");
2072 return -EINVAL;
2073 }
2074
2075 if (mddev->delta_disks < 0 ||
2076 (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2077 mddev->reshape_backwards = 1;
2078 else
2079 mddev->reshape_backwards = 0;
2080
2081 mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2082 rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
2083 }
2084
2085 } else {
2086 /*
2087 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2088 */
2089 struct raid_type *rt_cur = get_raid_type_by_ll(mddev->level, mddev->layout);
2090 struct raid_type *rt_new = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
2091
2092 if (rs_takeover_requested(rs)) {
2093 if (rt_cur && rt_new)
2094 DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",
2095 rt_cur->name, rt_new->name);
2096 else
2097 DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");
2098 return -EINVAL;
2099 } else if (rs_reshape_requested(rs)) {
2100 DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");
2101 if (mddev->layout != mddev->new_layout) {
2102 if (rt_cur && rt_new)
2103 DMERR(" current layout %s vs new layout %s",
2104 rt_cur->name, rt_new->name);
2105 else
2106 DMERR(" current layout 0x%X vs new layout 0x%X",
2107 le32_to_cpu(sb->layout), mddev->new_layout);
2108 }
2109 if (mddev->chunk_sectors != mddev->new_chunk_sectors)
2110 DMERR(" current stripe sectors %u vs new stripe sectors %u",
2111 mddev->chunk_sectors, mddev->new_chunk_sectors);
2112 if (rs->delta_disks)
2113 DMERR(" current %u disks vs new %u disks",
2114 mddev->raid_disks, mddev->raid_disks + rs->delta_disks);
2115 if (rs_is_raid10(rs)) {
2116 DMERR(" Old layout: %s w/ %u copies",
2117 raid10_md_layout_to_format(mddev->layout),
2118 raid10_md_layout_to_copies(mddev->layout));
2119 DMERR(" New layout: %s w/ %u copies",
2120 raid10_md_layout_to_format(mddev->new_layout),
2121 raid10_md_layout_to_copies(mddev->new_layout));
2122 }
2123 return -EINVAL;
2124 }
2125
2126 DMINFO("Discovered old metadata format; upgrading to extended metadata format");
2127 }
2128
2129 if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2130 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2131
2132 /*
2133 * During load, we set FirstUse if a new superblock was written.
2134 * There are two reasons we might not have a superblock:
2135 * 1) The raid set is brand new - in which case, all of the
2136 * devices must have their In_sync bit set. Also,
2137 * recovery_cp must be 0, unless forced.
2138 * 2) This is a new device being added to an old raid set
2139 * and the new device needs to be rebuilt - in which
2140 * case the In_sync bit will /not/ be set and
2141 * recovery_cp must be MaxSector.
2142 * 3) This is/are a new device(s) being added to an old
2143 * raid set during takeover to a higher raid level
2144 * to provide capacity for redundancy or during reshape
2145 * to add capacity to grow the raid set.
2146 */
2147 d = 0;
2148 rdev_for_each(r, mddev) {
2149 if (test_bit(FirstUse, &r->flags))
2150 new_devs++;
2151
2152 if (!test_bit(In_sync, &r->flags)) {
2153 DMINFO("Device %d specified for rebuild; clearing superblock",
2154 r->raid_disk);
2155 rebuilds++;
2156
2157 if (test_bit(FirstUse, &r->flags))
2158 rebuild_and_new++;
2159 }
2160
2161 d++;
2162 }
2163
2164 if (new_devs == rs->raid_disks || !rebuilds) {
2165 /* Replace a broken device */
2166 if (new_devs == 1 && !rs->delta_disks)
2167 ;
2168 if (new_devs == rs->raid_disks) {
2169 DMINFO("Superblocks created for new raid set");
2170 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2171 } else if (new_devs != rebuilds &&
2172 new_devs != rs->delta_disks) {
2173 DMERR("New device injected into existing raid set without "
2174 "'delta_disks' or 'rebuild' parameter specified");
2175 return -EINVAL;
2176 }
2177 } else if (new_devs && new_devs != rebuilds) {
2178 DMERR("%u 'rebuild' devices cannot be injected into"
2179 " a raid set with %u other first-time devices",
2180 rebuilds, new_devs);
2181 return -EINVAL;
2182 } else if (rebuilds) {
2183 if (rebuild_and_new && rebuilds != rebuild_and_new) {
2184 DMERR("new device%s provided without 'rebuild'",
2185 new_devs > 1 ? "s" : "");
2186 return -EINVAL;
2187 } else if (rs_is_recovering(rs)) {
2188 DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2189 (unsigned long long) mddev->recovery_cp);
2190 return -EINVAL;
2191 } else if (rs_is_reshaping(rs)) {
2192 DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2193 (unsigned long long) mddev->reshape_position);
2194 return -EINVAL;
2195 }
2196 }
2197
2198 /*
2199 * Now we set the Faulty bit for those devices that are
2200 * recorded in the superblock as failed.
2201 */
2202 sb_retrieve_failed_devices(sb, failed_devices);
2203 rdev_for_each(r, mddev) {
2204 if (!r->sb_page)
2205 continue;
2206 sb2 = page_address(r->sb_page);
2207 sb2->failed_devices = 0;
2208 memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2209
2210 /*
2211 * Check for any device re-ordering.
2212 */
2213 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2214 role = le32_to_cpu(sb2->array_position);
2215 if (role < 0)
2216 continue;
2217
2218 if (role != r->raid_disk) {
2219 if (rs_is_raid10(rs) && __is_raid10_near(mddev->layout)) {
2220 if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2221 rs->raid_disks % rs->raid10_copies) {
2222 rs->ti->error =
2223 "Cannot change raid10 near set to odd # of devices!";
2224 return -EINVAL;
2225 }
2226
2227 sb2->array_position = cpu_to_le32(r->raid_disk);
2228
2229 } else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2230 !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2231 !rt_is_raid1(rs->raid_type)) {
2232 rs->ti->error = "Cannot change device positions in raid set";
2233 return -EINVAL;
2234 }
2235
2236 DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2237 }
2238
2239 /*
2240 * Partial recovery is performed on
2241 * returning failed devices.
2242 */
2243 if (test_bit(role, (void *) failed_devices))
2244 set_bit(Faulty, &r->flags);
2245 }
2246 }
2247
2248 return 0;
2249}
2250
2251static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2252{
2253 struct mddev *mddev = &rs->md;
2254 struct dm_raid_superblock *sb;
2255
2256 if (rs_is_raid0(rs) || !rdev->sb_page)
2257 return 0;
2258
2259 sb = page_address(rdev->sb_page);
2260
2261 /*
2262 * If mddev->events is not set, we know we have not yet initialized
2263 * the array.
2264 */
2265 if (!mddev->events && super_init_validation(rs, rdev))
2266 return -EINVAL;
2267
2268 if (le32_to_cpu(sb->compat_features) &&
2269 le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2270 rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2271 return -EINVAL;
2272 }
2273
2274 if (sb->incompat_features) {
2275 rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2276 return -EINVAL;
2277 }
2278
2279 /* Enable bitmap creation for RAID levels != 0 */
2280 mddev->bitmap_info.offset = rt_is_raid0(rs->raid_type) ? 0 : to_sector(4096);
2281 rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2282
2283 if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2284 /* Retrieve device size stored in superblock to be prepared for shrink */
2285 rdev->sectors = le64_to_cpu(sb->sectors);
2286 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2287 if (rdev->recovery_offset == MaxSector)
2288 set_bit(In_sync, &rdev->flags);
2289 /*
2290 * If no reshape in progress -> we're recovering single
2291 * disk(s) and have to set the device(s) to out-of-sync
2292 */
2293 else if (!rs_is_reshaping(rs))
2294 clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2295 }
2296
2297 /*
2298 * If a device comes back, set it as not In_sync and no longer faulty.
2299 */
2300 if (test_and_clear_bit(Faulty, &rdev->flags)) {
2301 rdev->recovery_offset = 0;
2302 clear_bit(In_sync, &rdev->flags);
2303 rdev->saved_raid_disk = rdev->raid_disk;
2304 }
2305
2306 /* Reshape support -> restore repective data offsets */
2307 rdev->data_offset = le64_to_cpu(sb->data_offset);
2308 rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2309
2310 return 0;
2311}
2312
2313/*
2314 * Analyse superblocks and select the freshest.
2315 */
2316static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2317{
2318 int r;
2319 struct raid_dev *dev;
2320 struct md_rdev *rdev, *tmp, *freshest;
2321 struct mddev *mddev = &rs->md;
2322
2323 freshest = NULL;
2324 rdev_for_each_safe(rdev, tmp, mddev) {
2325 /*
2326 * Skipping super_load due to CTR_FLAG_SYNC will cause
2327 * the array to undergo initialization again as
2328 * though it were new. This is the intended effect
2329 * of the "sync" directive.
2330 *
2331 * When reshaping capability is added, we must ensure
2332 * that the "sync" directive is disallowed during the
2333 * reshape.
2334 */
2335 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2336 continue;
2337
2338 if (!rdev->meta_bdev)
2339 continue;
2340
2341 r = super_load(rdev, freshest);
2342
2343 switch (r) {
2344 case 1:
2345 freshest = rdev;
2346 break;
2347 case 0:
2348 break;
2349 default:
2350 /*
2351 * We have to keep any raid0 data/metadata device pairs or
2352 * the MD raid0 personality will fail to start the array.
2353 */
2354 if (rs_is_raid0(rs))
2355 continue;
2356
2357 dev = container_of(rdev, struct raid_dev, rdev);
2358 if (dev->meta_dev)
2359 dm_put_device(ti, dev->meta_dev);
2360
2361 dev->meta_dev = NULL;
2362 rdev->meta_bdev = NULL;
2363
2364 if (rdev->sb_page)
2365 put_page(rdev->sb_page);
2366
2367 rdev->sb_page = NULL;
2368
2369 rdev->sb_loaded = 0;
2370
2371 /*
2372 * We might be able to salvage the data device
2373 * even though the meta device has failed. For
2374 * now, we behave as though '- -' had been
2375 * set for this device in the table.
2376 */
2377 if (dev->data_dev)
2378 dm_put_device(ti, dev->data_dev);
2379
2380 dev->data_dev = NULL;
2381 rdev->bdev = NULL;
2382
2383 list_del(&rdev->same_set);
2384 }
2385 }
2386
2387 if (!freshest)
2388 return 0;
2389
2390 if (validate_raid_redundancy(rs)) {
2391 rs->ti->error = "Insufficient redundancy to activate array";
2392 return -EINVAL;
2393 }
2394
2395 /*
2396 * Validation of the freshest device provides the source of
2397 * validation for the remaining devices.
2398 */
2399 rs->ti->error = "Unable to assemble array: Invalid superblocks";
2400 if (super_validate(rs, freshest))
2401 return -EINVAL;
2402
2403 rdev_for_each(rdev, mddev)
2404 if ((rdev != freshest) && super_validate(rs, rdev))
2405 return -EINVAL;
2406 return 0;
2407}
2408
2409/*
2410 * Adjust data_offset and new_data_offset on all disk members of @rs
2411 * for out of place reshaping if requested by contructor
2412 *
2413 * We need free space at the beginning of each raid disk for forward
2414 * and at the end for backward reshapes which userspace has to provide
2415 * via remapping/reordering of space.
2416 */
2417static int rs_adjust_data_offsets(struct raid_set *rs)
2418{
2419 sector_t data_offset = 0, new_data_offset = 0;
2420 struct md_rdev *rdev;
2421
2422 /* Constructor did not request data offset change */
2423 if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2424 if (!rs_is_reshapable(rs))
2425 goto out;
2426
2427 return 0;
2428 }
2429
2430 /* HM FIXME: get InSync raid_dev? */
2431 rdev = &rs->dev[0].rdev;
2432
2433 if (rs->delta_disks < 0) {
2434 /*
2435 * Removing disks (reshaping backwards):
2436 *
2437 * - before reshape: data is at offset 0 and free space
2438 * is at end of each component LV
2439 *
2440 * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2441 */
2442 data_offset = 0;
2443 new_data_offset = rs->data_offset;
2444
2445 } else if (rs->delta_disks > 0) {
2446 /*
2447 * Adding disks (reshaping forwards):
2448 *
2449 * - before reshape: data is at offset rs->data_offset != 0 and
2450 * free space is at begin of each component LV
2451 *
2452 * - after reshape: data is at offset 0 on each component LV
2453 */
2454 data_offset = rs->data_offset;
2455 new_data_offset = 0;
2456
2457 } else {
2458 /*
2459 * User space passes in 0 for data offset after having removed reshape space
2460 *
2461 * - or - (data offset != 0)
2462 *
2463 * Changing RAID layout or chunk size -> toggle offsets
2464 *
2465 * - before reshape: data is at offset rs->data_offset 0 and
2466 * free space is at end of each component LV
2467 * -or-
2468 * data is at offset rs->data_offset != 0 and
2469 * free space is at begin of each component LV
2470 *
2471 * - after reshape: data is at offset 0 if it was at offset != 0
2472 * or at offset != 0 if it was at offset 0
2473 * on each component LV
2474 *
2475 */
2476 data_offset = rs->data_offset ? rdev->data_offset : 0;
2477 new_data_offset = data_offset ? 0 : rs->data_offset;
2478 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2479 }
2480
2481 /*
2482 * Make sure we got a minimum amount of free sectors per device
2483 */
2484 if (rs->data_offset &&
2485 to_sector(i_size_read(rdev->bdev->bd_inode)) - rdev->sectors < MIN_FREE_RESHAPE_SPACE) {
2486 rs->ti->error = data_offset ? "No space for forward reshape" :
2487 "No space for backward reshape";
2488 return -ENOSPC;
2489 }
2490out:
2491 /* Adjust data offsets on all rdevs */
2492 rdev_for_each(rdev, &rs->md) {
2493 rdev->data_offset = data_offset;
2494 rdev->new_data_offset = new_data_offset;
2495 }
2496
2497 return 0;
2498}
2499
2500/* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2501static void __reorder_raid_disk_indexes(struct raid_set *rs)
2502{
2503 int i = 0;
2504 struct md_rdev *rdev;
2505
2506 rdev_for_each(rdev, &rs->md) {
2507 rdev->raid_disk = i++;
2508 rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2509 }
2510}
2511
2512/*
2513 * Setup @rs for takeover by a different raid level
2514 */
2515static int rs_setup_takeover(struct raid_set *rs)
2516{
2517 struct mddev *mddev = &rs->md;
2518 struct md_rdev *rdev;
2519 unsigned int d = mddev->raid_disks = rs->raid_disks;
2520 sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2521
2522 if (rt_is_raid10(rs->raid_type)) {
2523 if (mddev->level == 0) {
2524 /* Userpace reordered disks -> adjust raid_disk indexes */
2525 __reorder_raid_disk_indexes(rs);
2526
2527 /* raid0 -> raid10_far layout */
2528 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2529 rs->raid10_copies);
2530 } else if (mddev->level == 1)
2531 /* raid1 -> raid10_near layout */
2532 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2533 rs->raid_disks);
2534 else
2535 return -EINVAL;
2536
2537 }
2538
2539 clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2540 mddev->recovery_cp = MaxSector;
2541
2542 while (d--) {
2543 rdev = &rs->dev[d].rdev;
2544
2545 if (test_bit(d, (void *) rs->rebuild_disks)) {
2546 clear_bit(In_sync, &rdev->flags);
2547 clear_bit(Faulty, &rdev->flags);
2548 mddev->recovery_cp = rdev->recovery_offset = 0;
2549 /* Bitmap has to be created when we do an "up" takeover */
2550 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2551 }
2552
2553 rdev->new_data_offset = new_data_offset;
2554 }
2555
2556 return 0;
2557}
2558
2559/* Prepare @rs for reshape */
2560static int rs_prepare_reshape(struct raid_set *rs)
2561{
2562 bool reshape;
2563 struct mddev *mddev = &rs->md;
2564
2565 if (rs_is_raid10(rs)) {
2566 if (rs->raid_disks != mddev->raid_disks &&
2567 __is_raid10_near(mddev->layout) &&
2568 rs->raid10_copies &&
2569 rs->raid10_copies != __raid10_near_copies(mddev->layout)) {
2570 /*
2571 * raid disk have to be multiple of data copies to allow this conversion,
2572 *
2573 * This is actually not a reshape it is a
2574 * rebuild of any additional mirrors per group
2575 */
2576 if (rs->raid_disks % rs->raid10_copies) {
2577 rs->ti->error = "Can't reshape raid10 mirror groups";
2578 return -EINVAL;
2579 }
2580
2581 /* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2582 __reorder_raid_disk_indexes(rs);
2583 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2584 rs->raid10_copies);
2585 mddev->new_layout = mddev->layout;
2586 reshape = false;
2587 } else
2588 reshape = true;
2589
2590 } else if (rs_is_raid456(rs))
2591 reshape = true;
2592
2593 else if (rs_is_raid1(rs)) {
2594 if (rs->delta_disks) {
2595 /* Process raid1 via delta_disks */
2596 mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
2597 reshape = true;
2598 } else {
2599 /* Process raid1 without delta_disks */
2600 mddev->raid_disks = rs->raid_disks;
2601 reshape = false;
2602 }
2603 } else {
2604 rs->ti->error = "Called with bogus raid type";
2605 return -EINVAL;
2606 }
2607
2608 if (reshape) {
2609 set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2610 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2611 } else if (mddev->raid_disks < rs->raid_disks)
2612 /* Create new superblocks and bitmaps, if any new disks */
2613 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2614
2615 return 0;
2616}
2617
2618/*
2619 *
2620 * - change raid layout
2621 * - change chunk size
2622 * - add disks
2623 * - remove disks
2624 */
2625static int rs_setup_reshape(struct raid_set *rs)
2626{
2627 int r = 0;
2628 unsigned int cur_raid_devs, d;
2629 struct mddev *mddev = &rs->md;
2630 struct md_rdev *rdev;
2631
2632 mddev->delta_disks = rs->delta_disks;
2633 cur_raid_devs = mddev->raid_disks;
2634
2635 /* Ignore impossible layout change whilst adding/removing disks */
2636 if (mddev->delta_disks &&
2637 mddev->layout != mddev->new_layout) {
2638 DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2639 mddev->new_layout = mddev->layout;
2640 }
2641
2642 /*
2643 * Adjust array size:
2644 *
2645 * - in case of adding disks, array size has
2646 * to grow after the disk adding reshape,
2647 * which'll hapen in the event handler;
2648 * reshape will happen forward, so space has to
2649 * be available at the beginning of each disk
2650 *
2651 * - in case of removing disks, array size
2652 * has to shrink before starting the reshape,
2653 * which'll happen here;
2654 * reshape will happen backward, so space has to
2655 * be available at the end of each disk
2656 *
2657 * - data_offset and new_data_offset are
2658 * adjusted for aforementioned out of place
2659 * reshaping based on userspace passing in
2660 * the "data_offset <sectors>" key/value
2661 * pair via the constructor
2662 */
2663
2664 /* Add disk(s) */
2665 if (rs->delta_disks > 0) {
2666 /* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2667 for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2668 rdev = &rs->dev[d].rdev;
2669 clear_bit(In_sync, &rdev->flags);
2670
2671 /*
2672 * save_raid_disk needs to be -1, or recovery_offset will be set to 0
2673 * by md, which'll store that erroneously in the superblock on reshape
2674 */
2675 rdev->saved_raid_disk = -1;
2676 rdev->raid_disk = d;
2677
2678 rdev->sectors = mddev->dev_sectors;
2679 rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
2680 }
2681
2682 mddev->reshape_backwards = 0; /* adding disks -> forward reshape */
2683
2684 /* Remove disk(s) */
2685 } else if (rs->delta_disks < 0) {
2686 r = rs_set_dev_and_array_sectors(rs, true);
2687 mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2688
2689 /* Change layout and/or chunk size */
2690 } else {
2691 /*
2692 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2693 *
2694 * keeping number of disks and do layout change ->
2695 *
2696 * toggle reshape_backward depending on data_offset:
2697 *
2698 * - free space upfront -> reshape forward
2699 *
2700 * - free space at the end -> reshape backward
2701 *
2702 *
2703 * This utilizes free reshape space avoiding the need
2704 * for userspace to move (parts of) LV segments in
2705 * case of layout/chunksize change (for disk
2706 * adding/removing reshape space has to be at
2707 * the proper address (see above with delta_disks):
2708 *
2709 * add disk(s) -> begin
2710 * remove disk(s)-> end
2711 */
2712 mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2713 }
2714
2715 return r;
2716}
2717
2718/*
2719 * Enable/disable discard support on RAID set depending on
2720 * RAID level and discard properties of underlying RAID members.
2721 */
2722static void configure_discard_support(struct raid_set *rs)
2723{
2724 int i;
2725 bool raid456;
2726 struct dm_target *ti = rs->ti;
2727
2728 /* Assume discards not supported until after checks below. */
2729 ti->discards_supported = false;
2730
2731 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */
2732 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6);
2733
2734 for (i = 0; i < rs->raid_disks; i++) {
2735 struct request_queue *q;
2736
2737 if (!rs->dev[i].rdev.bdev)
2738 continue;
2739
2740 q = bdev_get_queue(rs->dev[i].rdev.bdev);
2741 if (!q || !blk_queue_discard(q))
2742 return;
2743
2744 if (raid456) {
2745 if (!q->limits.discard_zeroes_data)
2746 return;
2747 if (!devices_handle_discard_safely) {
2748 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2749 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2750 return;
2751 }
2752 }
2753 }
2754
2755 /* All RAID members properly support discards */
2756 ti->discards_supported = true;
2757
2758 /*
2759 * RAID1 and RAID10 personalities require bio splitting,
2760 * RAID0/4/5/6 don't and process large discard bios properly.
2761 */
2762 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10);
2763 ti->num_discard_bios = 1;
2764}
2765
2766/*
2767 * Construct a RAID0/1/10/4/5/6 mapping:
2768 * Args:
2769 * <raid_type> <#raid_params> <raid_params>{0,} \
2770 * <#raid_devs> [<meta_dev1> <dev1>]{1,}
2771 *
2772 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for
2773 * details on possible <raid_params>.
2774 *
2775 * Userspace is free to initialize the metadata devices, hence the superblocks to
2776 * enforce recreation based on the passed in table parameters.
2777 *
2778 */
2779static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
2780{
2781 int r;
2782 bool resize;
2783 struct raid_type *rt;
2784 unsigned int num_raid_params, num_raid_devs;
2785 sector_t calculated_dev_sectors;
2786 struct raid_set *rs = NULL;
2787 const char *arg;
2788 struct rs_layout rs_layout;
2789 struct dm_arg_set as = { argc, argv }, as_nrd;
2790 struct dm_arg _args[] = {
2791 { 0, as.argc, "Cannot understand number of raid parameters" },
2792 { 1, 254, "Cannot understand number of raid devices parameters" }
2793 };
2794
2795 /* Must have <raid_type> */
2796 arg = dm_shift_arg(&as);
2797 if (!arg) {
2798 ti->error = "No arguments";
2799 return -EINVAL;
2800 }
2801
2802 rt = get_raid_type(arg);
2803 if (!rt) {
2804 ti->error = "Unrecognised raid_type";
2805 return -EINVAL;
2806 }
2807
2808 /* Must have <#raid_params> */
2809 if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
2810 return -EINVAL;
2811
2812 /* number of raid device tupples <meta_dev data_dev> */
2813 as_nrd = as;
2814 dm_consume_args(&as_nrd, num_raid_params);
2815 _args[1].max = (as_nrd.argc - 1) / 2;
2816 if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
2817 return -EINVAL;
2818
2819 if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
2820 ti->error = "Invalid number of supplied raid devices";
2821 return -EINVAL;
2822 }
2823
2824 rs = raid_set_alloc(ti, rt, num_raid_devs);
2825 if (IS_ERR(rs))
2826 return PTR_ERR(rs);
2827
2828 r = parse_raid_params(rs, &as, num_raid_params);
2829 if (r)
2830 goto bad;
2831
2832 r = parse_dev_params(rs, &as);
2833 if (r)
2834 goto bad;
2835
2836 rs->md.sync_super = super_sync;
2837
2838 /*
2839 * Calculate ctr requested array and device sizes to allow
2840 * for superblock analysis needing device sizes defined.
2841 *
2842 * Any existing superblock will overwrite the array and device sizes
2843 */
2844 r = rs_set_dev_and_array_sectors(rs, false);
2845 if (r)
2846 goto bad;
2847
2848 calculated_dev_sectors = rs->dev[0].rdev.sectors;
2849
2850 /*
2851 * Backup any new raid set level, layout, ...
2852 * requested to be able to compare to superblock
2853 * members for conversion decisions.
2854 */
2855 rs_config_backup(rs, &rs_layout);
2856
2857 r = analyse_superblocks(ti, rs);
2858 if (r)
2859 goto bad;
2860
2861 resize = calculated_dev_sectors != rs->dev[0].rdev.sectors;
2862
2863 INIT_WORK(&rs->md.event_work, do_table_event);
2864 ti->private = rs;
2865 ti->num_flush_bios = 1;
2866
2867 /* Restore any requested new layout for conversion decision */
2868 rs_config_restore(rs, &rs_layout);
2869
2870 /*
2871 * Now that we have any superblock metadata available,
2872 * check for new, recovering, reshaping, to be taken over,
2873 * to be reshaped or an existing, unchanged raid set to
2874 * run in sequence.
2875 */
2876 if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
2877 /* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
2878 if (rs_is_raid6(rs) &&
2879 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
2880 ti->error = "'nosync' not allowed for new raid6 set";
2881 r = -EINVAL;
2882 goto bad;
2883 }
2884 rs_setup_recovery(rs, 0);
2885 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2886 rs_set_new(rs);
2887 } else if (rs_is_recovering(rs)) {
2888 /* A recovering raid set may be resized */
2889 ; /* skip setup rs */
2890 } else if (rs_is_reshaping(rs)) {
2891 /* Have to reject size change request during reshape */
2892 if (resize) {
2893 ti->error = "Can't resize a reshaping raid set";
2894 r = -EPERM;
2895 goto bad;
2896 }
2897 /* skip setup rs */
2898 } else if (rs_takeover_requested(rs)) {
2899 if (rs_is_reshaping(rs)) {
2900 ti->error = "Can't takeover a reshaping raid set";
2901 r = -EPERM;
2902 goto bad;
2903 }
2904
2905 /*
2906 * If a takeover is needed, userspace sets any additional
2907 * devices to rebuild and we can check for a valid request here.
2908 *
2909 * If acceptible, set the level to the new requested
2910 * one, prohibit requesting recovery, allow the raid
2911 * set to run and store superblocks during resume.
2912 */
2913 r = rs_check_takeover(rs);
2914 if (r)
2915 goto bad;
2916
2917 r = rs_setup_takeover(rs);
2918 if (r)
2919 goto bad;
2920
2921 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2922 /* Takeover ain't recovery, so disable recovery */
2923 rs_setup_recovery(rs, MaxSector);
2924 rs_set_new(rs);
2925 } else if (rs_reshape_requested(rs)) {
2926 /*
2927 * We can only prepare for a reshape here, because the
2928 * raid set needs to run to provide the repective reshape
2929 * check functions via its MD personality instance.
2930 *
2931 * So do the reshape check after md_run() succeeded.
2932 */
2933 r = rs_prepare_reshape(rs);
2934 if (r)
2935 return r;
2936
2937 /* Reshaping ain't recovery, so disable recovery */
2938 rs_setup_recovery(rs, MaxSector);
2939 rs_set_cur(rs);
2940 } else {
2941 /* May not set recovery when a device rebuild is requested */
2942 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
2943 rs_setup_recovery(rs, MaxSector);
2944 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2945 } else
2946 rs_setup_recovery(rs, test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ?
2947 0 : (resize ? calculated_dev_sectors : MaxSector));
2948 rs_set_cur(rs);
2949 }
2950
2951 /* If constructor requested it, change data and new_data offsets */
2952 r = rs_adjust_data_offsets(rs);
2953 if (r)
2954 goto bad;
2955
2956 /* Start raid set read-only and assumed clean to change in raid_resume() */
2957 rs->md.ro = 1;
2958 rs->md.in_sync = 1;
2959 set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
2960
2961 /* Has to be held on running the array */
2962 mddev_lock_nointr(&rs->md);
2963 r = md_run(&rs->md);
2964 rs->md.in_sync = 0; /* Assume already marked dirty */
2965
2966 if (r) {
2967 ti->error = "Failed to run raid array";
2968 mddev_unlock(&rs->md);
2969 goto bad;
2970 }
2971
2972 rs->callbacks.congested_fn = raid_is_congested;
2973 dm_table_add_target_callbacks(ti->table, &rs->callbacks);
2974
2975 mddev_suspend(&rs->md);
2976
2977 /* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
2978 if (rs_is_raid456(rs)) {
2979 r = rs_set_raid456_stripe_cache(rs);
2980 if (r)
2981 goto bad_stripe_cache;
2982 }
2983
2984 /* Now do an early reshape check */
2985 if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
2986 r = rs_check_reshape(rs);
2987 if (r)
2988 goto bad_check_reshape;
2989
2990 /* Restore new, ctr requested layout to perform check */
2991 rs_config_restore(rs, &rs_layout);
2992
2993 if (rs->md.pers->start_reshape) {
2994 r = rs->md.pers->check_reshape(&rs->md);
2995 if (r) {
2996 ti->error = "Reshape check failed";
2997 goto bad_check_reshape;
2998 }
2999 }
3000 }
3001
3002 /* Disable/enable discard support on raid set. */
3003 configure_discard_support(rs);
3004
3005 mddev_unlock(&rs->md);
3006 return 0;
3007
3008bad_stripe_cache:
3009bad_check_reshape:
3010 md_stop(&rs->md);
3011bad:
3012 raid_set_free(rs);
3013
3014 return r;
3015}
3016
3017static void raid_dtr(struct dm_target *ti)
3018{
3019 struct raid_set *rs = ti->private;
3020
3021 list_del_init(&rs->callbacks.list);
3022 md_stop(&rs->md);
3023 raid_set_free(rs);
3024}
3025
3026static int raid_map(struct dm_target *ti, struct bio *bio)
3027{
3028 struct raid_set *rs = ti->private;
3029 struct mddev *mddev = &rs->md;
3030
3031 /*
3032 * If we're reshaping to add disk(s)), ti->len and
3033 * mddev->array_sectors will differ during the process
3034 * (ti->len > mddev->array_sectors), so we have to requeue
3035 * bios with addresses > mddev->array_sectors here or
3036 * there will occur accesses past EOD of the component
3037 * data images thus erroring the raid set.
3038 */
3039 if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
3040 return DM_MAPIO_REQUEUE;
3041
3042 mddev->pers->make_request(mddev, bio);
3043
3044 return DM_MAPIO_SUBMITTED;
3045}
3046
3047/* Return string describing the current sync action of @mddev */
3048static const char *decipher_sync_action(struct mddev *mddev)
3049{
3050 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
3051 return "frozen";
3052
3053 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3054 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
3055 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
3056 return "reshape";
3057
3058 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
3059 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
3060 return "resync";
3061 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
3062 return "check";
3063 return "repair";
3064 }
3065
3066 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
3067 return "recover";
3068 }
3069
3070 return "idle";
3071}
3072
3073/*
3074 * Return status string @rdev
3075 *
3076 * Status characters:
3077 *
3078 * 'D' = Dead/Failed device
3079 * 'a' = Alive but not in-sync
3080 * 'A' = Alive and in-sync
3081 */
3082static const char *__raid_dev_status(struct md_rdev *rdev, bool array_in_sync)
3083{
3084 if (test_bit(Faulty, &rdev->flags))
3085 return "D";
3086 else if (!array_in_sync || !test_bit(In_sync, &rdev->flags))
3087 return "a";
3088 else
3089 return "A";
3090}
3091
3092/* Helper to return resync/reshape progress for @rs and @array_in_sync */
3093static sector_t rs_get_progress(struct raid_set *rs,
3094 sector_t resync_max_sectors, bool *array_in_sync)
3095{
3096 sector_t r, recovery_cp, curr_resync_completed;
3097 struct mddev *mddev = &rs->md;
3098
3099 curr_resync_completed = mddev->curr_resync_completed ?: mddev->recovery_cp;
3100 recovery_cp = mddev->recovery_cp;
3101 *array_in_sync = false;
3102
3103 if (rs_is_raid0(rs)) {
3104 r = resync_max_sectors;
3105 *array_in_sync = true;
3106
3107 } else {
3108 r = mddev->reshape_position;
3109
3110 /* Reshape is relative to the array size */
3111 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ||
3112 r != MaxSector) {
3113 if (r == MaxSector) {
3114 *array_in_sync = true;
3115 r = resync_max_sectors;
3116 } else {
3117 /* Got to reverse on backward reshape */
3118 if (mddev->reshape_backwards)
3119 r = mddev->array_sectors - r;
3120
3121 /* Devide by # of data stripes */
3122 sector_div(r, mddev_data_stripes(rs));
3123 }
3124
3125 /* Sync is relative to the component device size */
3126 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3127 r = curr_resync_completed;
3128 else
3129 r = recovery_cp;
3130
3131 if (r == MaxSector) {
3132 /*
3133 * Sync complete.
3134 */
3135 *array_in_sync = true;
3136 r = resync_max_sectors;
3137 } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
3138 /*
3139 * If "check" or "repair" is occurring, the raid set has
3140 * undergone an initial sync and the health characters
3141 * should not be 'a' anymore.
3142 */
3143 *array_in_sync = true;
3144 } else {
3145 struct md_rdev *rdev;
3146
3147 /*
3148 * The raid set may be doing an initial sync, or it may
3149 * be rebuilding individual components. If all the
3150 * devices are In_sync, then it is the raid set that is
3151 * being initialized.
3152 */
3153 rdev_for_each(rdev, mddev)
3154 if (!test_bit(In_sync, &rdev->flags))
3155 *array_in_sync = true;
3156#if 0
3157 r = 0; /* HM FIXME: TESTME: https://bugzilla.redhat.com/show_bug.cgi?id=1210637 ? */
3158#endif
3159 }
3160 }
3161
3162 return r;
3163}
3164
3165/* Helper to return @dev name or "-" if !@dev */
3166static const char *__get_dev_name(struct dm_dev *dev)
3167{
3168 return dev ? dev->name : "-";
3169}
3170
3171static void raid_status(struct dm_target *ti, status_type_t type,
3172 unsigned int status_flags, char *result, unsigned int maxlen)
3173{
3174 struct raid_set *rs = ti->private;
3175 struct mddev *mddev = &rs->md;
3176 struct r5conf *conf = mddev->private;
3177 int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3178 bool array_in_sync;
3179 unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3180 unsigned int sz = 0;
3181 unsigned int rebuild_disks;
3182 unsigned int write_mostly_params = 0;
3183 sector_t progress, resync_max_sectors, resync_mismatches;
3184 const char *sync_action;
3185 struct raid_type *rt;
3186 struct md_rdev *rdev;
3187
3188 switch (type) {
3189 case STATUSTYPE_INFO:
3190 /* *Should* always succeed */
3191 rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3192 if (!rt)
3193 return;
3194
3195 DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3196
3197 /* Access most recent mddev properties for status output */
3198 smp_rmb();
3199 /* Get sensible max sectors even if raid set not yet started */
3200 resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3201 mddev->resync_max_sectors : mddev->dev_sectors;
3202 progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync);
3203 resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
3204 atomic64_read(&mddev->resync_mismatches) : 0;
3205 sync_action = decipher_sync_action(&rs->md);
3206
3207 /* HM FIXME: do we want another state char for raid0? It shows 'D' or 'A' now */
3208 rdev_for_each(rdev, mddev)
3209 DMEMIT(__raid_dev_status(rdev, array_in_sync));
3210
3211 /*
3212 * In-sync/Reshape ratio:
3213 * The in-sync ratio shows the progress of:
3214 * - Initializing the raid set
3215 * - Rebuilding a subset of devices of the raid set
3216 * The user can distinguish between the two by referring
3217 * to the status characters.
3218 *
3219 * The reshape ratio shows the progress of
3220 * changing the raid layout or the number of
3221 * disks of a raid set
3222 */
3223 DMEMIT(" %llu/%llu", (unsigned long long) progress,
3224 (unsigned long long) resync_max_sectors);
3225
3226 /*
3227 * v1.5.0+:
3228 *
3229 * Sync action:
3230 * See Documentation/device-mapper/dm-raid.txt for
3231 * information on each of these states.
3232 */
3233 DMEMIT(" %s", sync_action);
3234
3235 /*
3236 * v1.5.0+:
3237 *
3238 * resync_mismatches/mismatch_cnt
3239 * This field shows the number of discrepancies found when
3240 * performing a "check" of the raid set.
3241 */
3242 DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3243
3244 /*
3245 * v1.9.0+:
3246 *
3247 * data_offset (needed for out of space reshaping)
3248 * This field shows the data offset into the data
3249 * image LV where the first stripes data starts.
3250 *
3251 * We keep data_offset equal on all raid disks of the set,
3252 * so retrieving it from the first raid disk is sufficient.
3253 */
3254 DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
3255 break;
3256
3257 case STATUSTYPE_TABLE:
3258 /* Report the table line string you would use to construct this raid set */
3259
3260 /* Calculate raid parameter count */
3261 for (i = 0; i < rs->raid_disks; i++)
3262 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3263 write_mostly_params += 2;
3264 rebuild_disks = memweight(rs->rebuild_disks, DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks));
3265 raid_param_cnt += rebuild_disks * 2 +
3266 write_mostly_params +
3267 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3268 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
3269 /* Emit table line */
3270 DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3271 if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3272 DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3273 raid10_md_layout_to_format(mddev->layout));
3274 if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3275 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3276 raid10_md_layout_to_copies(mddev->layout));
3277 if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3278 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3279 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3280 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
3281 if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3282 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3283 (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3284 if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3285 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3286 (unsigned long long) rs->data_offset);
3287 if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3288 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3289 mddev->bitmap_info.daemon_sleep);
3290 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3291 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3292 max(rs->delta_disks, mddev->delta_disks));
3293 if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3294 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3295 max_nr_stripes);
3296 if (rebuild_disks)
3297 for (i = 0; i < rs->raid_disks; i++)
3298 if (test_bit(rs->dev[i].rdev.raid_disk, (void *) rs->rebuild_disks))
3299 DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD),
3300 rs->dev[i].rdev.raid_disk);
3301 if (write_mostly_params)
3302 for (i = 0; i < rs->raid_disks; i++)
3303 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3304 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3305 rs->dev[i].rdev.raid_disk);
3306 if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3307 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3308 mddev->bitmap_info.max_write_behind);
3309 if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3310 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3311 mddev->sync_speed_max);
3312 if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3313 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3314 mddev->sync_speed_min);
3315 DMEMIT(" %d", rs->raid_disks);
3316 for (i = 0; i < rs->raid_disks; i++)
3317 DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
3318 __get_dev_name(rs->dev[i].data_dev));
3319 }
3320}
3321
3322static int raid_message(struct dm_target *ti, unsigned int argc, char **argv)
3323{
3324 struct raid_set *rs = ti->private;
3325 struct mddev *mddev = &rs->md;
3326
3327 if (!mddev->pers || !mddev->pers->sync_request)
3328 return -EINVAL;
3329
3330 if (!strcasecmp(argv[0], "frozen"))
3331 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3332 else
3333 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3334
3335 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
3336 if (mddev->sync_thread) {
3337 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3338 md_reap_sync_thread(mddev);
3339 }
3340 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3341 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
3342 return -EBUSY;
3343 else if (!strcasecmp(argv[0], "resync"))
3344 ; /* MD_RECOVERY_NEEDED set below */
3345 else if (!strcasecmp(argv[0], "recover"))
3346 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3347 else {
3348 if (!strcasecmp(argv[0], "check"))
3349 set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3350 else if (!!strcasecmp(argv[0], "repair"))
3351 return -EINVAL;
3352 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3353 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3354 }
3355 if (mddev->ro == 2) {
3356 /* A write to sync_action is enough to justify
3357 * canceling read-auto mode
3358 */
3359 mddev->ro = 0;
3360 if (!mddev->suspended && mddev->sync_thread)
3361 md_wakeup_thread(mddev->sync_thread);
3362 }
3363 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3364 if (!mddev->suspended && mddev->thread)
3365 md_wakeup_thread(mddev->thread);
3366
3367 return 0;
3368}
3369
3370static int raid_iterate_devices(struct dm_target *ti,
3371 iterate_devices_callout_fn fn, void *data)
3372{
3373 struct raid_set *rs = ti->private;
3374 unsigned int i;
3375 int r = 0;
3376
3377 for (i = 0; !r && i < rs->md.raid_disks; i++)
3378 if (rs->dev[i].data_dev)
3379 r = fn(ti,
3380 rs->dev[i].data_dev,
3381 0, /* No offset on data devs */
3382 rs->md.dev_sectors,
3383 data);
3384
3385 return r;
3386}
3387
3388static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3389{
3390 struct raid_set *rs = ti->private;
3391 unsigned int chunk_size = to_bytes(rs->md.chunk_sectors);
3392
3393 blk_limits_io_min(limits, chunk_size);
3394 blk_limits_io_opt(limits, chunk_size * mddev_data_stripes(rs));
3395}
3396
3397static void raid_presuspend(struct dm_target *ti)
3398{
3399 struct raid_set *rs = ti->private;
3400
3401 md_stop_writes(&rs->md);
3402}
3403
3404static void raid_postsuspend(struct dm_target *ti)
3405{
3406 struct raid_set *rs = ti->private;
3407
3408 if (!rs->md.suspended)
3409 mddev_suspend(&rs->md);
3410
3411 rs->md.ro = 1;
3412}
3413
3414static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3415{
3416 int i;
3417 uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];
3418 unsigned long flags;
3419 bool cleared = false;
3420 struct dm_raid_superblock *sb;
3421 struct mddev *mddev = &rs->md;
3422 struct md_rdev *r;
3423
3424 /* RAID personalities have to provide hot add/remove methods or we need to bail out. */
3425 if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)
3426 return;
3427
3428 memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));
3429
3430 for (i = 0; i < rs->md.raid_disks; i++) {
3431 r = &rs->dev[i].rdev;
3432 if (test_bit(Faulty, &r->flags) && r->sb_page &&
3433 sync_page_io(r, 0, r->sb_size, r->sb_page,
3434 REQ_OP_READ, 0, true)) {
3435 DMINFO("Faulty %s device #%d has readable super block."
3436 " Attempting to revive it.",
3437 rs->raid_type->name, i);
3438
3439 /*
3440 * Faulty bit may be set, but sometimes the array can
3441 * be suspended before the personalities can respond
3442 * by removing the device from the array (i.e. calling
3443 * 'hot_remove_disk'). If they haven't yet removed
3444 * the failed device, its 'raid_disk' number will be
3445 * '>= 0' - meaning we must call this function
3446 * ourselves.
3447 */
3448 if ((r->raid_disk >= 0) &&
3449 (mddev->pers->hot_remove_disk(mddev, r) != 0))
3450 /* Failed to revive this device, try next */
3451 continue;
3452
3453 r->raid_disk = i;
3454 r->saved_raid_disk = i;
3455 flags = r->flags;
3456 clear_bit(Faulty, &r->flags);
3457 clear_bit(WriteErrorSeen, &r->flags);
3458 clear_bit(In_sync, &r->flags);
3459 if (mddev->pers->hot_add_disk(mddev, r)) {
3460 r->raid_disk = -1;
3461 r->saved_raid_disk = -1;
3462 r->flags = flags;
3463 } else {
3464 r->recovery_offset = 0;
3465 set_bit(i, (void *) cleared_failed_devices);
3466 cleared = true;
3467 }
3468 }
3469 }
3470
3471 /* If any failed devices could be cleared, update all sbs failed_devices bits */
3472 if (cleared) {
3473 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
3474
3475 rdev_for_each(r, &rs->md) {
3476 sb = page_address(r->sb_page);
3477 sb_retrieve_failed_devices(sb, failed_devices);
3478
3479 for (i = 0; i < DISKS_ARRAY_ELEMS; i++)
3480 failed_devices[i] &= ~cleared_failed_devices[i];
3481
3482 sb_update_failed_devices(sb, failed_devices);
3483 }
3484 }
3485}
3486
3487static int __load_dirty_region_bitmap(struct raid_set *rs)
3488{
3489 int r = 0;
3490
3491 /* Try loading the bitmap unless "raid0", which does not have one */
3492 if (!rs_is_raid0(rs) &&
3493 !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
3494 r = bitmap_load(&rs->md);
3495 if (r)
3496 DMERR("Failed to load bitmap");
3497 }
3498
3499 return r;
3500}
3501
3502/* Enforce updating all superblocks */
3503static void rs_update_sbs(struct raid_set *rs)
3504{
3505 struct mddev *mddev = &rs->md;
3506 int ro = mddev->ro;
3507
3508 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
3509 mddev->ro = 0;
3510 md_update_sb(mddev, 1);
3511 mddev->ro = ro;
3512}
3513
3514/*
3515 * Reshape changes raid algorithm of @rs to new one within personality
3516 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3517 * disks from a raid set thus growing/shrinking it or resizes the set
3518 *
3519 * Call mddev_lock_nointr() before!
3520 */
3521static int rs_start_reshape(struct raid_set *rs)
3522{
3523 int r;
3524 struct mddev *mddev = &rs->md;
3525 struct md_personality *pers = mddev->pers;
3526
3527 r = rs_setup_reshape(rs);
3528 if (r)
3529 return r;
3530
3531 /* Need to be resumed to be able to start reshape, recovery is frozen until raid_resume() though */
3532 if (mddev->suspended)
3533 mddev_resume(mddev);
3534
3535 /*
3536 * Check any reshape constraints enforced by the personalility
3537 *
3538 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3539 */
3540 r = pers->check_reshape(mddev);
3541 if (r) {
3542 rs->ti->error = "pers->check_reshape() failed";
3543 return r;
3544 }
3545
3546 /*
3547 * Personality may not provide start reshape method in which
3548 * case check_reshape above has already covered everything
3549 */
3550 if (pers->start_reshape) {
3551 r = pers->start_reshape(mddev);
3552 if (r) {
3553 rs->ti->error = "pers->start_reshape() failed";
3554 return r;
3555 }
3556 }
3557
3558 /* Suspend because a resume will happen in raid_resume() */
3559 if (!mddev->suspended)
3560 mddev_suspend(mddev);
3561
3562 /*
3563 * Now reshape got set up, update superblocks to
3564 * reflect the fact so that a table reload will
3565 * access proper superblock content in the ctr.
3566 */
3567 rs_update_sbs(rs);
3568
3569 return 0;
3570}
3571
3572static int raid_preresume(struct dm_target *ti)
3573{
3574 int r;
3575 struct raid_set *rs = ti->private;
3576 struct mddev *mddev = &rs->md;
3577
3578 /* This is a resume after a suspend of the set -> it's already started */
3579 if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
3580 return 0;
3581
3582 /*
3583 * The superblocks need to be updated on disk if the
3584 * array is new or new devices got added (thus zeroed
3585 * out by userspace) or __load_dirty_region_bitmap
3586 * will overwrite them in core with old data or fail.
3587 */
3588 if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
3589 rs_update_sbs(rs);
3590
3591 /* Load the bitmap from disk unless raid0 */
3592 r = __load_dirty_region_bitmap(rs);
3593 if (r)
3594 return r;
3595
3596 /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */
3597 if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
3598 mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) {
3599 r = bitmap_resize(mddev->bitmap, mddev->dev_sectors,
3600 to_bytes(rs->requested_bitmap_chunk_sectors), 0);
3601 if (r)
3602 DMERR("Failed to resize bitmap");
3603 }
3604
3605 /* Check for any resize/reshape on @rs and adjust/initiate */
3606 /* Be prepared for mddev_resume() in raid_resume() */
3607 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3608 if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
3609 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3610 mddev->resync_min = mddev->recovery_cp;
3611 }
3612
3613 rs_set_capacity(rs);
3614
3615 /* Check for any reshape request unless new raid set */
3616 if (test_and_clear_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3617 /* Initiate a reshape. */
3618 mddev_lock_nointr(mddev);
3619 r = rs_start_reshape(rs);
3620 mddev_unlock(mddev);
3621 if (r)
3622 DMWARN("Failed to check/start reshape, continuing without change");
3623 r = 0;
3624 }
3625
3626 return r;
3627}
3628
3629#define RESUME_STAY_FROZEN_FLAGS (CTR_FLAG_DELTA_DISKS | CTR_FLAG_DATA_OFFSET)
3630
3631static void raid_resume(struct dm_target *ti)
3632{
3633 struct raid_set *rs = ti->private;
3634 struct mddev *mddev = &rs->md;
3635
3636 if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
3637 /*
3638 * A secondary resume while the device is active.
3639 * Take this opportunity to check whether any failed
3640 * devices are reachable again.
3641 */
3642 attempt_restore_of_faulty_devices(rs);
3643 }
3644
3645 mddev->ro = 0;
3646 mddev->in_sync = 0;
3647
3648 /*
3649 * Keep the RAID set frozen if reshape/rebuild flags are set.
3650 * The RAID set is unfrozen once the next table load/resume,
3651 * which clears the reshape/rebuild flags, occurs.
3652 * This ensures that the constructor for the inactive table
3653 * retrieves an up-to-date reshape_position.
3654 */
3655 if (!(rs->ctr_flags & RESUME_STAY_FROZEN_FLAGS))
3656 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3657
3658 if (mddev->suspended)
3659 mddev_resume(mddev);
3660}
3661
3662static struct target_type raid_target = {
3663 .name = "raid",
3664 .version = {1, 9, 1},
3665 .module = THIS_MODULE,
3666 .ctr = raid_ctr,
3667 .dtr = raid_dtr,
3668 .map = raid_map,
3669 .status = raid_status,
3670 .message = raid_message,
3671 .iterate_devices = raid_iterate_devices,
3672 .io_hints = raid_io_hints,
3673 .presuspend = raid_presuspend,
3674 .postsuspend = raid_postsuspend,
3675 .preresume = raid_preresume,
3676 .resume = raid_resume,
3677};
3678
3679static int __init dm_raid_init(void)
3680{
3681 DMINFO("Loading target version %u.%u.%u",
3682 raid_target.version[0],
3683 raid_target.version[1],
3684 raid_target.version[2]);
3685 return dm_register_target(&raid_target);
3686}
3687
3688static void __exit dm_raid_exit(void)
3689{
3690 dm_unregister_target(&raid_target);
3691}
3692
3693module_init(dm_raid_init);
3694module_exit(dm_raid_exit);
3695
3696module_param(devices_handle_discard_safely, bool, 0644);
3697MODULE_PARM_DESC(devices_handle_discard_safely,
3698 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
3699
3700MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
3701MODULE_ALIAS("dm-raid0");
3702MODULE_ALIAS("dm-raid1");
3703MODULE_ALIAS("dm-raid10");
3704MODULE_ALIAS("dm-raid4");
3705MODULE_ALIAS("dm-raid5");
3706MODULE_ALIAS("dm-raid6");
3707MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
3708MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
3709MODULE_LICENSE("GPL");
1/*
2 * Copyright (C) 2010-2011 Neil Brown
3 * Copyright (C) 2010-2011 Red Hat, Inc. All rights reserved.
4 *
5 * This file is released under the GPL.
6 */
7
8#include <linux/slab.h>
9#include <linux/module.h>
10
11#include "md.h"
12#include "raid1.h"
13#include "raid5.h"
14#include "raid10.h"
15#include "bitmap.h"
16
17#include <linux/device-mapper.h>
18
19#define DM_MSG_PREFIX "raid"
20
21/*
22 * The following flags are used by dm-raid.c to set up the array state.
23 * They must be cleared before md_run is called.
24 */
25#define FirstUse 10 /* rdev flag */
26
27struct raid_dev {
28 /*
29 * Two DM devices, one to hold metadata and one to hold the
30 * actual data/parity. The reason for this is to not confuse
31 * ti->len and give more flexibility in altering size and
32 * characteristics.
33 *
34 * While it is possible for this device to be associated
35 * with a different physical device than the data_dev, it
36 * is intended for it to be the same.
37 * |--------- Physical Device ---------|
38 * |- meta_dev -|------ data_dev ------|
39 */
40 struct dm_dev *meta_dev;
41 struct dm_dev *data_dev;
42 struct md_rdev rdev;
43};
44
45/*
46 * Flags for rs->print_flags field.
47 */
48#define DMPF_SYNC 0x1
49#define DMPF_NOSYNC 0x2
50#define DMPF_REBUILD 0x4
51#define DMPF_DAEMON_SLEEP 0x8
52#define DMPF_MIN_RECOVERY_RATE 0x10
53#define DMPF_MAX_RECOVERY_RATE 0x20
54#define DMPF_MAX_WRITE_BEHIND 0x40
55#define DMPF_STRIPE_CACHE 0x80
56#define DMPF_REGION_SIZE 0x100
57#define DMPF_RAID10_COPIES 0x200
58#define DMPF_RAID10_FORMAT 0x400
59
60struct raid_set {
61 struct dm_target *ti;
62
63 uint32_t bitmap_loaded;
64 uint32_t print_flags;
65
66 struct mddev md;
67 struct raid_type *raid_type;
68 struct dm_target_callbacks callbacks;
69
70 struct raid_dev dev[0];
71};
72
73/* Supported raid types and properties. */
74static struct raid_type {
75 const char *name; /* RAID algorithm. */
76 const char *descr; /* Descriptor text for logging. */
77 const unsigned parity_devs; /* # of parity devices. */
78 const unsigned minimal_devs; /* minimal # of devices in set. */
79 const unsigned level; /* RAID level. */
80 const unsigned algorithm; /* RAID algorithm. */
81} raid_types[] = {
82 {"raid1", "RAID1 (mirroring)", 0, 2, 1, 0 /* NONE */},
83 {"raid10", "RAID10 (striped mirrors)", 0, 2, 10, UINT_MAX /* Varies */},
84 {"raid4", "RAID4 (dedicated parity disk)", 1, 2, 5, ALGORITHM_PARITY_0},
85 {"raid5_la", "RAID5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC},
86 {"raid5_ra", "RAID5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC},
87 {"raid5_ls", "RAID5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC},
88 {"raid5_rs", "RAID5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC},
89 {"raid6_zr", "RAID6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART},
90 {"raid6_nr", "RAID6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART},
91 {"raid6_nc", "RAID6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE}
92};
93
94static char *raid10_md_layout_to_format(int layout)
95{
96 /*
97 * Bit 16 and 17 stand for "offset" and "use_far_sets"
98 * Refer to MD's raid10.c for details
99 */
100 if ((layout & 0x10000) && (layout & 0x20000))
101 return "offset";
102
103 if ((layout & 0xFF) > 1)
104 return "near";
105
106 return "far";
107}
108
109static unsigned raid10_md_layout_to_copies(int layout)
110{
111 if ((layout & 0xFF) > 1)
112 return layout & 0xFF;
113 return (layout >> 8) & 0xFF;
114}
115
116static int raid10_format_to_md_layout(char *format, unsigned copies)
117{
118 unsigned n = 1, f = 1;
119
120 if (!strcmp("near", format))
121 n = copies;
122 else
123 f = copies;
124
125 if (!strcmp("offset", format))
126 return 0x30000 | (f << 8) | n;
127
128 if (!strcmp("far", format))
129 return 0x20000 | (f << 8) | n;
130
131 return (f << 8) | n;
132}
133
134static struct raid_type *get_raid_type(char *name)
135{
136 int i;
137
138 for (i = 0; i < ARRAY_SIZE(raid_types); i++)
139 if (!strcmp(raid_types[i].name, name))
140 return &raid_types[i];
141
142 return NULL;
143}
144
145static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *raid_type, unsigned raid_devs)
146{
147 unsigned i;
148 struct raid_set *rs;
149
150 if (raid_devs <= raid_type->parity_devs) {
151 ti->error = "Insufficient number of devices";
152 return ERR_PTR(-EINVAL);
153 }
154
155 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL);
156 if (!rs) {
157 ti->error = "Cannot allocate raid context";
158 return ERR_PTR(-ENOMEM);
159 }
160
161 mddev_init(&rs->md);
162
163 rs->ti = ti;
164 rs->raid_type = raid_type;
165 rs->md.raid_disks = raid_devs;
166 rs->md.level = raid_type->level;
167 rs->md.new_level = rs->md.level;
168 rs->md.layout = raid_type->algorithm;
169 rs->md.new_layout = rs->md.layout;
170 rs->md.delta_disks = 0;
171 rs->md.recovery_cp = 0;
172
173 for (i = 0; i < raid_devs; i++)
174 md_rdev_init(&rs->dev[i].rdev);
175
176 /*
177 * Remaining items to be initialized by further RAID params:
178 * rs->md.persistent
179 * rs->md.external
180 * rs->md.chunk_sectors
181 * rs->md.new_chunk_sectors
182 * rs->md.dev_sectors
183 */
184
185 return rs;
186}
187
188static void context_free(struct raid_set *rs)
189{
190 int i;
191
192 for (i = 0; i < rs->md.raid_disks; i++) {
193 if (rs->dev[i].meta_dev)
194 dm_put_device(rs->ti, rs->dev[i].meta_dev);
195 md_rdev_clear(&rs->dev[i].rdev);
196 if (rs->dev[i].data_dev)
197 dm_put_device(rs->ti, rs->dev[i].data_dev);
198 }
199
200 kfree(rs);
201}
202
203/*
204 * For every device we have two words
205 * <meta_dev>: meta device name or '-' if missing
206 * <data_dev>: data device name or '-' if missing
207 *
208 * The following are permitted:
209 * - -
210 * - <data_dev>
211 * <meta_dev> <data_dev>
212 *
213 * The following is not allowed:
214 * <meta_dev> -
215 *
216 * This code parses those words. If there is a failure,
217 * the caller must use context_free to unwind the operations.
218 */
219static int dev_parms(struct raid_set *rs, char **argv)
220{
221 int i;
222 int rebuild = 0;
223 int metadata_available = 0;
224 int ret = 0;
225
226 for (i = 0; i < rs->md.raid_disks; i++, argv += 2) {
227 rs->dev[i].rdev.raid_disk = i;
228
229 rs->dev[i].meta_dev = NULL;
230 rs->dev[i].data_dev = NULL;
231
232 /*
233 * There are no offsets, since there is a separate device
234 * for data and metadata.
235 */
236 rs->dev[i].rdev.data_offset = 0;
237 rs->dev[i].rdev.mddev = &rs->md;
238
239 if (strcmp(argv[0], "-")) {
240 ret = dm_get_device(rs->ti, argv[0],
241 dm_table_get_mode(rs->ti->table),
242 &rs->dev[i].meta_dev);
243 rs->ti->error = "RAID metadata device lookup failure";
244 if (ret)
245 return ret;
246
247 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
248 if (!rs->dev[i].rdev.sb_page)
249 return -ENOMEM;
250 }
251
252 if (!strcmp(argv[1], "-")) {
253 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
254 (!rs->dev[i].rdev.recovery_offset)) {
255 rs->ti->error = "Drive designated for rebuild not specified";
256 return -EINVAL;
257 }
258
259 rs->ti->error = "No data device supplied with metadata device";
260 if (rs->dev[i].meta_dev)
261 return -EINVAL;
262
263 continue;
264 }
265
266 ret = dm_get_device(rs->ti, argv[1],
267 dm_table_get_mode(rs->ti->table),
268 &rs->dev[i].data_dev);
269 if (ret) {
270 rs->ti->error = "RAID device lookup failure";
271 return ret;
272 }
273
274 if (rs->dev[i].meta_dev) {
275 metadata_available = 1;
276 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
277 }
278 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
279 list_add(&rs->dev[i].rdev.same_set, &rs->md.disks);
280 if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
281 rebuild++;
282 }
283
284 if (metadata_available) {
285 rs->md.external = 0;
286 rs->md.persistent = 1;
287 rs->md.major_version = 2;
288 } else if (rebuild && !rs->md.recovery_cp) {
289 /*
290 * Without metadata, we will not be able to tell if the array
291 * is in-sync or not - we must assume it is not. Therefore,
292 * it is impossible to rebuild a drive.
293 *
294 * Even if there is metadata, the on-disk information may
295 * indicate that the array is not in-sync and it will then
296 * fail at that time.
297 *
298 * User could specify 'nosync' option if desperate.
299 */
300 DMERR("Unable to rebuild drive while array is not in-sync");
301 rs->ti->error = "RAID device lookup failure";
302 return -EINVAL;
303 }
304
305 return 0;
306}
307
308/*
309 * validate_region_size
310 * @rs
311 * @region_size: region size in sectors. If 0, pick a size (4MiB default).
312 *
313 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
314 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
315 *
316 * Returns: 0 on success, -EINVAL on failure.
317 */
318static int validate_region_size(struct raid_set *rs, unsigned long region_size)
319{
320 unsigned long min_region_size = rs->ti->len / (1 << 21);
321
322 if (!region_size) {
323 /*
324 * Choose a reasonable default. All figures in sectors.
325 */
326 if (min_region_size > (1 << 13)) {
327 /* If not a power of 2, make it the next power of 2 */
328 if (min_region_size & (min_region_size - 1))
329 region_size = 1 << fls(region_size);
330 DMINFO("Choosing default region size of %lu sectors",
331 region_size);
332 } else {
333 DMINFO("Choosing default region size of 4MiB");
334 region_size = 1 << 13; /* sectors */
335 }
336 } else {
337 /*
338 * Validate user-supplied value.
339 */
340 if (region_size > rs->ti->len) {
341 rs->ti->error = "Supplied region size is too large";
342 return -EINVAL;
343 }
344
345 if (region_size < min_region_size) {
346 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
347 region_size, min_region_size);
348 rs->ti->error = "Supplied region size is too small";
349 return -EINVAL;
350 }
351
352 if (!is_power_of_2(region_size)) {
353 rs->ti->error = "Region size is not a power of 2";
354 return -EINVAL;
355 }
356
357 if (region_size < rs->md.chunk_sectors) {
358 rs->ti->error = "Region size is smaller than the chunk size";
359 return -EINVAL;
360 }
361 }
362
363 /*
364 * Convert sectors to bytes.
365 */
366 rs->md.bitmap_info.chunksize = (region_size << 9);
367
368 return 0;
369}
370
371/*
372 * validate_raid_redundancy
373 * @rs
374 *
375 * Determine if there are enough devices in the array that haven't
376 * failed (or are being rebuilt) to form a usable array.
377 *
378 * Returns: 0 on success, -EINVAL on failure.
379 */
380static int validate_raid_redundancy(struct raid_set *rs)
381{
382 unsigned i, rebuild_cnt = 0;
383 unsigned rebuilds_per_group = 0, copies, d;
384 unsigned group_size, last_group_start;
385
386 for (i = 0; i < rs->md.raid_disks; i++)
387 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
388 !rs->dev[i].rdev.sb_page)
389 rebuild_cnt++;
390
391 switch (rs->raid_type->level) {
392 case 1:
393 if (rebuild_cnt >= rs->md.raid_disks)
394 goto too_many;
395 break;
396 case 4:
397 case 5:
398 case 6:
399 if (rebuild_cnt > rs->raid_type->parity_devs)
400 goto too_many;
401 break;
402 case 10:
403 copies = raid10_md_layout_to_copies(rs->md.layout);
404 if (rebuild_cnt < copies)
405 break;
406
407 /*
408 * It is possible to have a higher rebuild count for RAID10,
409 * as long as the failed devices occur in different mirror
410 * groups (i.e. different stripes).
411 *
412 * When checking "near" format, make sure no adjacent devices
413 * have failed beyond what can be handled. In addition to the
414 * simple case where the number of devices is a multiple of the
415 * number of copies, we must also handle cases where the number
416 * of devices is not a multiple of the number of copies.
417 * E.g. dev1 dev2 dev3 dev4 dev5
418 * A A B B C
419 * C D D E E
420 */
421 if (!strcmp("near", raid10_md_layout_to_format(rs->md.layout))) {
422 for (i = 0; i < rs->md.raid_disks * copies; i++) {
423 if (!(i % copies))
424 rebuilds_per_group = 0;
425 d = i % rs->md.raid_disks;
426 if ((!rs->dev[d].rdev.sb_page ||
427 !test_bit(In_sync, &rs->dev[d].rdev.flags)) &&
428 (++rebuilds_per_group >= copies))
429 goto too_many;
430 }
431 break;
432 }
433
434 /*
435 * When checking "far" and "offset" formats, we need to ensure
436 * that the device that holds its copy is not also dead or
437 * being rebuilt. (Note that "far" and "offset" formats only
438 * support two copies right now. These formats also only ever
439 * use the 'use_far_sets' variant.)
440 *
441 * This check is somewhat complicated by the need to account
442 * for arrays that are not a multiple of (far) copies. This
443 * results in the need to treat the last (potentially larger)
444 * set differently.
445 */
446 group_size = (rs->md.raid_disks / copies);
447 last_group_start = (rs->md.raid_disks / group_size) - 1;
448 last_group_start *= group_size;
449 for (i = 0; i < rs->md.raid_disks; i++) {
450 if (!(i % copies) && !(i > last_group_start))
451 rebuilds_per_group = 0;
452 if ((!rs->dev[i].rdev.sb_page ||
453 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
454 (++rebuilds_per_group >= copies))
455 goto too_many;
456 }
457 break;
458 default:
459 if (rebuild_cnt)
460 return -EINVAL;
461 }
462
463 return 0;
464
465too_many:
466 return -EINVAL;
467}
468
469/*
470 * Possible arguments are...
471 * <chunk_size> [optional_args]
472 *
473 * Argument definitions
474 * <chunk_size> The number of sectors per disk that
475 * will form the "stripe"
476 * [[no]sync] Force or prevent recovery of the
477 * entire array
478 * [rebuild <idx>] Rebuild the drive indicated by the index
479 * [daemon_sleep <ms>] Time between bitmap daemon work to
480 * clear bits
481 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
482 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
483 * [write_mostly <idx>] Indicate a write mostly drive via index
484 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
485 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs
486 * [region_size <sectors>] Defines granularity of bitmap
487 *
488 * RAID10-only options:
489 * [raid10_copies <# copies>] Number of copies. (Default: 2)
490 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
491 */
492static int parse_raid_params(struct raid_set *rs, char **argv,
493 unsigned num_raid_params)
494{
495 char *raid10_format = "near";
496 unsigned raid10_copies = 2;
497 unsigned i;
498 unsigned long value, region_size = 0;
499 sector_t sectors_per_dev = rs->ti->len;
500 sector_t max_io_len;
501 char *key;
502
503 /*
504 * First, parse the in-order required arguments
505 * "chunk_size" is the only argument of this type.
506 */
507 if ((kstrtoul(argv[0], 10, &value) < 0)) {
508 rs->ti->error = "Bad chunk size";
509 return -EINVAL;
510 } else if (rs->raid_type->level == 1) {
511 if (value)
512 DMERR("Ignoring chunk size parameter for RAID 1");
513 value = 0;
514 } else if (!is_power_of_2(value)) {
515 rs->ti->error = "Chunk size must be a power of 2";
516 return -EINVAL;
517 } else if (value < 8) {
518 rs->ti->error = "Chunk size value is too small";
519 return -EINVAL;
520 }
521
522 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
523 argv++;
524 num_raid_params--;
525
526 /*
527 * We set each individual device as In_sync with a completed
528 * 'recovery_offset'. If there has been a device failure or
529 * replacement then one of the following cases applies:
530 *
531 * 1) User specifies 'rebuild'.
532 * - Device is reset when param is read.
533 * 2) A new device is supplied.
534 * - No matching superblock found, resets device.
535 * 3) Device failure was transient and returns on reload.
536 * - Failure noticed, resets device for bitmap replay.
537 * 4) Device hadn't completed recovery after previous failure.
538 * - Superblock is read and overrides recovery_offset.
539 *
540 * What is found in the superblocks of the devices is always
541 * authoritative, unless 'rebuild' or '[no]sync' was specified.
542 */
543 for (i = 0; i < rs->md.raid_disks; i++) {
544 set_bit(In_sync, &rs->dev[i].rdev.flags);
545 rs->dev[i].rdev.recovery_offset = MaxSector;
546 }
547
548 /*
549 * Second, parse the unordered optional arguments
550 */
551 for (i = 0; i < num_raid_params; i++) {
552 if (!strcasecmp(argv[i], "nosync")) {
553 rs->md.recovery_cp = MaxSector;
554 rs->print_flags |= DMPF_NOSYNC;
555 continue;
556 }
557 if (!strcasecmp(argv[i], "sync")) {
558 rs->md.recovery_cp = 0;
559 rs->print_flags |= DMPF_SYNC;
560 continue;
561 }
562
563 /* The rest of the optional arguments come in key/value pairs */
564 if ((i + 1) >= num_raid_params) {
565 rs->ti->error = "Wrong number of raid parameters given";
566 return -EINVAL;
567 }
568
569 key = argv[i++];
570
571 /* Parameters that take a string value are checked here. */
572 if (!strcasecmp(key, "raid10_format")) {
573 if (rs->raid_type->level != 10) {
574 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
575 return -EINVAL;
576 }
577 if (strcmp("near", argv[i]) &&
578 strcmp("far", argv[i]) &&
579 strcmp("offset", argv[i])) {
580 rs->ti->error = "Invalid 'raid10_format' value given";
581 return -EINVAL;
582 }
583 raid10_format = argv[i];
584 rs->print_flags |= DMPF_RAID10_FORMAT;
585 continue;
586 }
587
588 if (kstrtoul(argv[i], 10, &value) < 0) {
589 rs->ti->error = "Bad numerical argument given in raid params";
590 return -EINVAL;
591 }
592
593 /* Parameters that take a numeric value are checked here */
594 if (!strcasecmp(key, "rebuild")) {
595 if (value >= rs->md.raid_disks) {
596 rs->ti->error = "Invalid rebuild index given";
597 return -EINVAL;
598 }
599 clear_bit(In_sync, &rs->dev[value].rdev.flags);
600 rs->dev[value].rdev.recovery_offset = 0;
601 rs->print_flags |= DMPF_REBUILD;
602 } else if (!strcasecmp(key, "write_mostly")) {
603 if (rs->raid_type->level != 1) {
604 rs->ti->error = "write_mostly option is only valid for RAID1";
605 return -EINVAL;
606 }
607 if (value >= rs->md.raid_disks) {
608 rs->ti->error = "Invalid write_mostly drive index given";
609 return -EINVAL;
610 }
611 set_bit(WriteMostly, &rs->dev[value].rdev.flags);
612 } else if (!strcasecmp(key, "max_write_behind")) {
613 if (rs->raid_type->level != 1) {
614 rs->ti->error = "max_write_behind option is only valid for RAID1";
615 return -EINVAL;
616 }
617 rs->print_flags |= DMPF_MAX_WRITE_BEHIND;
618
619 /*
620 * In device-mapper, we specify things in sectors, but
621 * MD records this value in kB
622 */
623 value /= 2;
624 if (value > COUNTER_MAX) {
625 rs->ti->error = "Max write-behind limit out of range";
626 return -EINVAL;
627 }
628 rs->md.bitmap_info.max_write_behind = value;
629 } else if (!strcasecmp(key, "daemon_sleep")) {
630 rs->print_flags |= DMPF_DAEMON_SLEEP;
631 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
632 rs->ti->error = "daemon sleep period out of range";
633 return -EINVAL;
634 }
635 rs->md.bitmap_info.daemon_sleep = value;
636 } else if (!strcasecmp(key, "stripe_cache")) {
637 rs->print_flags |= DMPF_STRIPE_CACHE;
638
639 /*
640 * In device-mapper, we specify things in sectors, but
641 * MD records this value in kB
642 */
643 value /= 2;
644
645 if ((rs->raid_type->level != 5) &&
646 (rs->raid_type->level != 6)) {
647 rs->ti->error = "Inappropriate argument: stripe_cache";
648 return -EINVAL;
649 }
650 if (raid5_set_cache_size(&rs->md, (int)value)) {
651 rs->ti->error = "Bad stripe_cache size";
652 return -EINVAL;
653 }
654 } else if (!strcasecmp(key, "min_recovery_rate")) {
655 rs->print_flags |= DMPF_MIN_RECOVERY_RATE;
656 if (value > INT_MAX) {
657 rs->ti->error = "min_recovery_rate out of range";
658 return -EINVAL;
659 }
660 rs->md.sync_speed_min = (int)value;
661 } else if (!strcasecmp(key, "max_recovery_rate")) {
662 rs->print_flags |= DMPF_MAX_RECOVERY_RATE;
663 if (value > INT_MAX) {
664 rs->ti->error = "max_recovery_rate out of range";
665 return -EINVAL;
666 }
667 rs->md.sync_speed_max = (int)value;
668 } else if (!strcasecmp(key, "region_size")) {
669 rs->print_flags |= DMPF_REGION_SIZE;
670 region_size = value;
671 } else if (!strcasecmp(key, "raid10_copies") &&
672 (rs->raid_type->level == 10)) {
673 if ((value < 2) || (value > 0xFF)) {
674 rs->ti->error = "Bad value for 'raid10_copies'";
675 return -EINVAL;
676 }
677 rs->print_flags |= DMPF_RAID10_COPIES;
678 raid10_copies = value;
679 } else {
680 DMERR("Unable to parse RAID parameter: %s", key);
681 rs->ti->error = "Unable to parse RAID parameters";
682 return -EINVAL;
683 }
684 }
685
686 if (validate_region_size(rs, region_size))
687 return -EINVAL;
688
689 if (rs->md.chunk_sectors)
690 max_io_len = rs->md.chunk_sectors;
691 else
692 max_io_len = region_size;
693
694 if (dm_set_target_max_io_len(rs->ti, max_io_len))
695 return -EINVAL;
696
697 if (rs->raid_type->level == 10) {
698 if (raid10_copies > rs->md.raid_disks) {
699 rs->ti->error = "Not enough devices to satisfy specification";
700 return -EINVAL;
701 }
702
703 /*
704 * If the format is not "near", we only support
705 * two copies at the moment.
706 */
707 if (strcmp("near", raid10_format) && (raid10_copies > 2)) {
708 rs->ti->error = "Too many copies for given RAID10 format.";
709 return -EINVAL;
710 }
711
712 /* (Len * #mirrors) / #devices */
713 sectors_per_dev = rs->ti->len * raid10_copies;
714 sector_div(sectors_per_dev, rs->md.raid_disks);
715
716 rs->md.layout = raid10_format_to_md_layout(raid10_format,
717 raid10_copies);
718 rs->md.new_layout = rs->md.layout;
719 } else if ((rs->raid_type->level > 1) &&
720 sector_div(sectors_per_dev,
721 (rs->md.raid_disks - rs->raid_type->parity_devs))) {
722 rs->ti->error = "Target length not divisible by number of data devices";
723 return -EINVAL;
724 }
725 rs->md.dev_sectors = sectors_per_dev;
726
727 /* Assume there are no metadata devices until the drives are parsed */
728 rs->md.persistent = 0;
729 rs->md.external = 1;
730
731 return 0;
732}
733
734static void do_table_event(struct work_struct *ws)
735{
736 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
737
738 dm_table_event(rs->ti->table);
739}
740
741static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
742{
743 struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
744
745 if (rs->raid_type->level == 1)
746 return md_raid1_congested(&rs->md, bits);
747
748 if (rs->raid_type->level == 10)
749 return md_raid10_congested(&rs->md, bits);
750
751 return md_raid5_congested(&rs->md, bits);
752}
753
754/*
755 * This structure is never routinely used by userspace, unlike md superblocks.
756 * Devices with this superblock should only ever be accessed via device-mapper.
757 */
758#define DM_RAID_MAGIC 0x64526D44
759struct dm_raid_superblock {
760 __le32 magic; /* "DmRd" */
761 __le32 features; /* Used to indicate possible future changes */
762
763 __le32 num_devices; /* Number of devices in this array. (Max 64) */
764 __le32 array_position; /* The position of this drive in the array */
765
766 __le64 events; /* Incremented by md when superblock updated */
767 __le64 failed_devices; /* Bit field of devices to indicate failures */
768
769 /*
770 * This offset tracks the progress of the repair or replacement of
771 * an individual drive.
772 */
773 __le64 disk_recovery_offset;
774
775 /*
776 * This offset tracks the progress of the initial array
777 * synchronisation/parity calculation.
778 */
779 __le64 array_resync_offset;
780
781 /*
782 * RAID characteristics
783 */
784 __le32 level;
785 __le32 layout;
786 __le32 stripe_sectors;
787
788 __u8 pad[452]; /* Round struct to 512 bytes. */
789 /* Always set to 0 when writing. */
790} __packed;
791
792static int read_disk_sb(struct md_rdev *rdev, int size)
793{
794 BUG_ON(!rdev->sb_page);
795
796 if (rdev->sb_loaded)
797 return 0;
798
799 if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, 1)) {
800 DMERR("Failed to read superblock of device at position %d",
801 rdev->raid_disk);
802 md_error(rdev->mddev, rdev);
803 return -EINVAL;
804 }
805
806 rdev->sb_loaded = 1;
807
808 return 0;
809}
810
811static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
812{
813 int i;
814 uint64_t failed_devices;
815 struct dm_raid_superblock *sb;
816 struct raid_set *rs = container_of(mddev, struct raid_set, md);
817
818 sb = page_address(rdev->sb_page);
819 failed_devices = le64_to_cpu(sb->failed_devices);
820
821 for (i = 0; i < mddev->raid_disks; i++)
822 if (!rs->dev[i].data_dev ||
823 test_bit(Faulty, &(rs->dev[i].rdev.flags)))
824 failed_devices |= (1ULL << i);
825
826 memset(sb, 0, sizeof(*sb));
827
828 sb->magic = cpu_to_le32(DM_RAID_MAGIC);
829 sb->features = cpu_to_le32(0); /* No features yet */
830
831 sb->num_devices = cpu_to_le32(mddev->raid_disks);
832 sb->array_position = cpu_to_le32(rdev->raid_disk);
833
834 sb->events = cpu_to_le64(mddev->events);
835 sb->failed_devices = cpu_to_le64(failed_devices);
836
837 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
838 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
839
840 sb->level = cpu_to_le32(mddev->level);
841 sb->layout = cpu_to_le32(mddev->layout);
842 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
843}
844
845/*
846 * super_load
847 *
848 * This function creates a superblock if one is not found on the device
849 * and will decide which superblock to use if there's a choice.
850 *
851 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
852 */
853static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
854{
855 int ret;
856 struct dm_raid_superblock *sb;
857 struct dm_raid_superblock *refsb;
858 uint64_t events_sb, events_refsb;
859
860 rdev->sb_start = 0;
861 rdev->sb_size = sizeof(*sb);
862
863 ret = read_disk_sb(rdev, rdev->sb_size);
864 if (ret)
865 return ret;
866
867 sb = page_address(rdev->sb_page);
868
869 /*
870 * Two cases that we want to write new superblocks and rebuild:
871 * 1) New device (no matching magic number)
872 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
873 */
874 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
875 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
876 super_sync(rdev->mddev, rdev);
877
878 set_bit(FirstUse, &rdev->flags);
879
880 /* Force writing of superblocks to disk */
881 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags);
882
883 /* Any superblock is better than none, choose that if given */
884 return refdev ? 0 : 1;
885 }
886
887 if (!refdev)
888 return 1;
889
890 events_sb = le64_to_cpu(sb->events);
891
892 refsb = page_address(refdev->sb_page);
893 events_refsb = le64_to_cpu(refsb->events);
894
895 return (events_sb > events_refsb) ? 1 : 0;
896}
897
898static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev)
899{
900 int role;
901 struct raid_set *rs = container_of(mddev, struct raid_set, md);
902 uint64_t events_sb;
903 uint64_t failed_devices;
904 struct dm_raid_superblock *sb;
905 uint32_t new_devs = 0;
906 uint32_t rebuilds = 0;
907 struct md_rdev *r;
908 struct dm_raid_superblock *sb2;
909
910 sb = page_address(rdev->sb_page);
911 events_sb = le64_to_cpu(sb->events);
912 failed_devices = le64_to_cpu(sb->failed_devices);
913
914 /*
915 * Initialise to 1 if this is a new superblock.
916 */
917 mddev->events = events_sb ? : 1;
918
919 /*
920 * Reshaping is not currently allowed
921 */
922 if (le32_to_cpu(sb->level) != mddev->level) {
923 DMERR("Reshaping arrays not yet supported. (RAID level change)");
924 return -EINVAL;
925 }
926 if (le32_to_cpu(sb->layout) != mddev->layout) {
927 DMERR("Reshaping arrays not yet supported. (RAID layout change)");
928 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout);
929 DMERR(" Old layout: %s w/ %d copies",
930 raid10_md_layout_to_format(le32_to_cpu(sb->layout)),
931 raid10_md_layout_to_copies(le32_to_cpu(sb->layout)));
932 DMERR(" New layout: %s w/ %d copies",
933 raid10_md_layout_to_format(mddev->layout),
934 raid10_md_layout_to_copies(mddev->layout));
935 return -EINVAL;
936 }
937 if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) {
938 DMERR("Reshaping arrays not yet supported. (stripe sectors change)");
939 return -EINVAL;
940 }
941
942 /* We can only change the number of devices in RAID1 right now */
943 if ((rs->raid_type->level != 1) &&
944 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) {
945 DMERR("Reshaping arrays not yet supported. (device count change)");
946 return -EINVAL;
947 }
948
949 if (!(rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC)))
950 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
951
952 /*
953 * During load, we set FirstUse if a new superblock was written.
954 * There are two reasons we might not have a superblock:
955 * 1) The array is brand new - in which case, all of the
956 * devices must have their In_sync bit set. Also,
957 * recovery_cp must be 0, unless forced.
958 * 2) This is a new device being added to an old array
959 * and the new device needs to be rebuilt - in which
960 * case the In_sync bit will /not/ be set and
961 * recovery_cp must be MaxSector.
962 */
963 rdev_for_each(r, mddev) {
964 if (!test_bit(In_sync, &r->flags)) {
965 DMINFO("Device %d specified for rebuild: "
966 "Clearing superblock", r->raid_disk);
967 rebuilds++;
968 } else if (test_bit(FirstUse, &r->flags))
969 new_devs++;
970 }
971
972 if (!rebuilds) {
973 if (new_devs == mddev->raid_disks) {
974 DMINFO("Superblocks created for new array");
975 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
976 } else if (new_devs) {
977 DMERR("New device injected "
978 "into existing array without 'rebuild' "
979 "parameter specified");
980 return -EINVAL;
981 }
982 } else if (new_devs) {
983 DMERR("'rebuild' devices cannot be "
984 "injected into an array with other first-time devices");
985 return -EINVAL;
986 } else if (mddev->recovery_cp != MaxSector) {
987 DMERR("'rebuild' specified while array is not in-sync");
988 return -EINVAL;
989 }
990
991 /*
992 * Now we set the Faulty bit for those devices that are
993 * recorded in the superblock as failed.
994 */
995 rdev_for_each(r, mddev) {
996 if (!r->sb_page)
997 continue;
998 sb2 = page_address(r->sb_page);
999 sb2->failed_devices = 0;
1000
1001 /*
1002 * Check for any device re-ordering.
1003 */
1004 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
1005 role = le32_to_cpu(sb2->array_position);
1006 if (role != r->raid_disk) {
1007 if (rs->raid_type->level != 1) {
1008 rs->ti->error = "Cannot change device "
1009 "positions in RAID array";
1010 return -EINVAL;
1011 }
1012 DMINFO("RAID1 device #%d now at position #%d",
1013 role, r->raid_disk);
1014 }
1015
1016 /*
1017 * Partial recovery is performed on
1018 * returning failed devices.
1019 */
1020 if (failed_devices & (1 << role))
1021 set_bit(Faulty, &r->flags);
1022 }
1023 }
1024
1025 return 0;
1026}
1027
1028static int super_validate(struct mddev *mddev, struct md_rdev *rdev)
1029{
1030 struct dm_raid_superblock *sb = page_address(rdev->sb_page);
1031
1032 /*
1033 * If mddev->events is not set, we know we have not yet initialized
1034 * the array.
1035 */
1036 if (!mddev->events && super_init_validation(mddev, rdev))
1037 return -EINVAL;
1038
1039 mddev->bitmap_info.offset = 4096 >> 9; /* Enable bitmap creation */
1040 rdev->mddev->bitmap_info.default_offset = 4096 >> 9;
1041 if (!test_bit(FirstUse, &rdev->flags)) {
1042 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
1043 if (rdev->recovery_offset != MaxSector)
1044 clear_bit(In_sync, &rdev->flags);
1045 }
1046
1047 /*
1048 * If a device comes back, set it as not In_sync and no longer faulty.
1049 */
1050 if (test_bit(Faulty, &rdev->flags)) {
1051 clear_bit(Faulty, &rdev->flags);
1052 clear_bit(In_sync, &rdev->flags);
1053 rdev->saved_raid_disk = rdev->raid_disk;
1054 rdev->recovery_offset = 0;
1055 }
1056
1057 clear_bit(FirstUse, &rdev->flags);
1058
1059 return 0;
1060}
1061
1062/*
1063 * Analyse superblocks and select the freshest.
1064 */
1065static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
1066{
1067 int ret;
1068 struct raid_dev *dev;
1069 struct md_rdev *rdev, *tmp, *freshest;
1070 struct mddev *mddev = &rs->md;
1071
1072 freshest = NULL;
1073 rdev_for_each_safe(rdev, tmp, mddev) {
1074 /*
1075 * Skipping super_load due to DMPF_SYNC will cause
1076 * the array to undergo initialization again as
1077 * though it were new. This is the intended effect
1078 * of the "sync" directive.
1079 *
1080 * When reshaping capability is added, we must ensure
1081 * that the "sync" directive is disallowed during the
1082 * reshape.
1083 */
1084 if (rs->print_flags & DMPF_SYNC)
1085 continue;
1086
1087 if (!rdev->meta_bdev)
1088 continue;
1089
1090 ret = super_load(rdev, freshest);
1091
1092 switch (ret) {
1093 case 1:
1094 freshest = rdev;
1095 break;
1096 case 0:
1097 break;
1098 default:
1099 dev = container_of(rdev, struct raid_dev, rdev);
1100 if (dev->meta_dev)
1101 dm_put_device(ti, dev->meta_dev);
1102
1103 dev->meta_dev = NULL;
1104 rdev->meta_bdev = NULL;
1105
1106 if (rdev->sb_page)
1107 put_page(rdev->sb_page);
1108
1109 rdev->sb_page = NULL;
1110
1111 rdev->sb_loaded = 0;
1112
1113 /*
1114 * We might be able to salvage the data device
1115 * even though the meta device has failed. For
1116 * now, we behave as though '- -' had been
1117 * set for this device in the table.
1118 */
1119 if (dev->data_dev)
1120 dm_put_device(ti, dev->data_dev);
1121
1122 dev->data_dev = NULL;
1123 rdev->bdev = NULL;
1124
1125 list_del(&rdev->same_set);
1126 }
1127 }
1128
1129 if (!freshest)
1130 return 0;
1131
1132 if (validate_raid_redundancy(rs)) {
1133 rs->ti->error = "Insufficient redundancy to activate array";
1134 return -EINVAL;
1135 }
1136
1137 /*
1138 * Validation of the freshest device provides the source of
1139 * validation for the remaining devices.
1140 */
1141 ti->error = "Unable to assemble array: Invalid superblocks";
1142 if (super_validate(mddev, freshest))
1143 return -EINVAL;
1144
1145 rdev_for_each(rdev, mddev)
1146 if ((rdev != freshest) && super_validate(mddev, rdev))
1147 return -EINVAL;
1148
1149 return 0;
1150}
1151
1152/*
1153 * Construct a RAID4/5/6 mapping:
1154 * Args:
1155 * <raid_type> <#raid_params> <raid_params> \
1156 * <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> }
1157 *
1158 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for
1159 * details on possible <raid_params>.
1160 */
1161static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv)
1162{
1163 int ret;
1164 struct raid_type *rt;
1165 unsigned long num_raid_params, num_raid_devs;
1166 struct raid_set *rs = NULL;
1167
1168 /* Must have at least <raid_type> <#raid_params> */
1169 if (argc < 2) {
1170 ti->error = "Too few arguments";
1171 return -EINVAL;
1172 }
1173
1174 /* raid type */
1175 rt = get_raid_type(argv[0]);
1176 if (!rt) {
1177 ti->error = "Unrecognised raid_type";
1178 return -EINVAL;
1179 }
1180 argc--;
1181 argv++;
1182
1183 /* number of RAID parameters */
1184 if (kstrtoul(argv[0], 10, &num_raid_params) < 0) {
1185 ti->error = "Cannot understand number of RAID parameters";
1186 return -EINVAL;
1187 }
1188 argc--;
1189 argv++;
1190
1191 /* Skip over RAID params for now and find out # of devices */
1192 if (num_raid_params + 1 > argc) {
1193 ti->error = "Arguments do not agree with counts given";
1194 return -EINVAL;
1195 }
1196
1197 if ((kstrtoul(argv[num_raid_params], 10, &num_raid_devs) < 0) ||
1198 (num_raid_devs >= INT_MAX)) {
1199 ti->error = "Cannot understand number of raid devices";
1200 return -EINVAL;
1201 }
1202
1203 rs = context_alloc(ti, rt, (unsigned)num_raid_devs);
1204 if (IS_ERR(rs))
1205 return PTR_ERR(rs);
1206
1207 ret = parse_raid_params(rs, argv, (unsigned)num_raid_params);
1208 if (ret)
1209 goto bad;
1210
1211 ret = -EINVAL;
1212
1213 argc -= num_raid_params + 1; /* +1: we already have num_raid_devs */
1214 argv += num_raid_params + 1;
1215
1216 if (argc != (num_raid_devs * 2)) {
1217 ti->error = "Supplied RAID devices does not match the count given";
1218 goto bad;
1219 }
1220
1221 ret = dev_parms(rs, argv);
1222 if (ret)
1223 goto bad;
1224
1225 rs->md.sync_super = super_sync;
1226 ret = analyse_superblocks(ti, rs);
1227 if (ret)
1228 goto bad;
1229
1230 INIT_WORK(&rs->md.event_work, do_table_event);
1231 ti->private = rs;
1232 ti->num_flush_bios = 1;
1233
1234 mutex_lock(&rs->md.reconfig_mutex);
1235 ret = md_run(&rs->md);
1236 rs->md.in_sync = 0; /* Assume already marked dirty */
1237 mutex_unlock(&rs->md.reconfig_mutex);
1238
1239 if (ret) {
1240 ti->error = "Fail to run raid array";
1241 goto bad;
1242 }
1243
1244 if (ti->len != rs->md.array_sectors) {
1245 ti->error = "Array size does not match requested target length";
1246 ret = -EINVAL;
1247 goto size_mismatch;
1248 }
1249 rs->callbacks.congested_fn = raid_is_congested;
1250 dm_table_add_target_callbacks(ti->table, &rs->callbacks);
1251
1252 mddev_suspend(&rs->md);
1253 return 0;
1254
1255size_mismatch:
1256 md_stop(&rs->md);
1257bad:
1258 context_free(rs);
1259
1260 return ret;
1261}
1262
1263static void raid_dtr(struct dm_target *ti)
1264{
1265 struct raid_set *rs = ti->private;
1266
1267 list_del_init(&rs->callbacks.list);
1268 md_stop(&rs->md);
1269 context_free(rs);
1270}
1271
1272static int raid_map(struct dm_target *ti, struct bio *bio)
1273{
1274 struct raid_set *rs = ti->private;
1275 struct mddev *mddev = &rs->md;
1276
1277 mddev->pers->make_request(mddev, bio);
1278
1279 return DM_MAPIO_SUBMITTED;
1280}
1281
1282static const char *decipher_sync_action(struct mddev *mddev)
1283{
1284 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
1285 return "frozen";
1286
1287 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
1288 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
1289 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
1290 return "reshape";
1291
1292 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
1293 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
1294 return "resync";
1295 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
1296 return "check";
1297 return "repair";
1298 }
1299
1300 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
1301 return "recover";
1302 }
1303
1304 return "idle";
1305}
1306
1307static void raid_status(struct dm_target *ti, status_type_t type,
1308 unsigned status_flags, char *result, unsigned maxlen)
1309{
1310 struct raid_set *rs = ti->private;
1311 unsigned raid_param_cnt = 1; /* at least 1 for chunksize */
1312 unsigned sz = 0;
1313 int i, array_in_sync = 0;
1314 sector_t sync;
1315
1316 switch (type) {
1317 case STATUSTYPE_INFO:
1318 DMEMIT("%s %d ", rs->raid_type->name, rs->md.raid_disks);
1319
1320 if (test_bit(MD_RECOVERY_RUNNING, &rs->md.recovery))
1321 sync = rs->md.curr_resync_completed;
1322 else
1323 sync = rs->md.recovery_cp;
1324
1325 if (sync >= rs->md.resync_max_sectors) {
1326 /*
1327 * Sync complete.
1328 */
1329 array_in_sync = 1;
1330 sync = rs->md.resync_max_sectors;
1331 } else if (test_bit(MD_RECOVERY_REQUESTED, &rs->md.recovery)) {
1332 /*
1333 * If "check" or "repair" is occurring, the array has
1334 * undergone and initial sync and the health characters
1335 * should not be 'a' anymore.
1336 */
1337 array_in_sync = 1;
1338 } else {
1339 /*
1340 * The array may be doing an initial sync, or it may
1341 * be rebuilding individual components. If all the
1342 * devices are In_sync, then it is the array that is
1343 * being initialized.
1344 */
1345 for (i = 0; i < rs->md.raid_disks; i++)
1346 if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
1347 array_in_sync = 1;
1348 }
1349
1350 /*
1351 * Status characters:
1352 * 'D' = Dead/Failed device
1353 * 'a' = Alive but not in-sync
1354 * 'A' = Alive and in-sync
1355 */
1356 for (i = 0; i < rs->md.raid_disks; i++) {
1357 if (test_bit(Faulty, &rs->dev[i].rdev.flags))
1358 DMEMIT("D");
1359 else if (!array_in_sync ||
1360 !test_bit(In_sync, &rs->dev[i].rdev.flags))
1361 DMEMIT("a");
1362 else
1363 DMEMIT("A");
1364 }
1365
1366 /*
1367 * In-sync ratio:
1368 * The in-sync ratio shows the progress of:
1369 * - Initializing the array
1370 * - Rebuilding a subset of devices of the array
1371 * The user can distinguish between the two by referring
1372 * to the status characters.
1373 */
1374 DMEMIT(" %llu/%llu",
1375 (unsigned long long) sync,
1376 (unsigned long long) rs->md.resync_max_sectors);
1377
1378 /*
1379 * Sync action:
1380 * See Documentation/device-mapper/dm-raid.c for
1381 * information on each of these states.
1382 */
1383 DMEMIT(" %s", decipher_sync_action(&rs->md));
1384
1385 /*
1386 * resync_mismatches/mismatch_cnt
1387 * This field shows the number of discrepancies found when
1388 * performing a "check" of the array.
1389 */
1390 DMEMIT(" %llu",
1391 (strcmp(rs->md.last_sync_action, "check")) ? 0 :
1392 (unsigned long long)
1393 atomic64_read(&rs->md.resync_mismatches));
1394 break;
1395 case STATUSTYPE_TABLE:
1396 /* The string you would use to construct this array */
1397 for (i = 0; i < rs->md.raid_disks; i++) {
1398 if ((rs->print_flags & DMPF_REBUILD) &&
1399 rs->dev[i].data_dev &&
1400 !test_bit(In_sync, &rs->dev[i].rdev.flags))
1401 raid_param_cnt += 2; /* for rebuilds */
1402 if (rs->dev[i].data_dev &&
1403 test_bit(WriteMostly, &rs->dev[i].rdev.flags))
1404 raid_param_cnt += 2;
1405 }
1406
1407 raid_param_cnt += (hweight32(rs->print_flags & ~DMPF_REBUILD) * 2);
1408 if (rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC))
1409 raid_param_cnt--;
1410
1411 DMEMIT("%s %u %u", rs->raid_type->name,
1412 raid_param_cnt, rs->md.chunk_sectors);
1413
1414 if ((rs->print_flags & DMPF_SYNC) &&
1415 (rs->md.recovery_cp == MaxSector))
1416 DMEMIT(" sync");
1417 if (rs->print_flags & DMPF_NOSYNC)
1418 DMEMIT(" nosync");
1419
1420 for (i = 0; i < rs->md.raid_disks; i++)
1421 if ((rs->print_flags & DMPF_REBUILD) &&
1422 rs->dev[i].data_dev &&
1423 !test_bit(In_sync, &rs->dev[i].rdev.flags))
1424 DMEMIT(" rebuild %u", i);
1425
1426 if (rs->print_flags & DMPF_DAEMON_SLEEP)
1427 DMEMIT(" daemon_sleep %lu",
1428 rs->md.bitmap_info.daemon_sleep);
1429
1430 if (rs->print_flags & DMPF_MIN_RECOVERY_RATE)
1431 DMEMIT(" min_recovery_rate %d", rs->md.sync_speed_min);
1432
1433 if (rs->print_flags & DMPF_MAX_RECOVERY_RATE)
1434 DMEMIT(" max_recovery_rate %d", rs->md.sync_speed_max);
1435
1436 for (i = 0; i < rs->md.raid_disks; i++)
1437 if (rs->dev[i].data_dev &&
1438 test_bit(WriteMostly, &rs->dev[i].rdev.flags))
1439 DMEMIT(" write_mostly %u", i);
1440
1441 if (rs->print_flags & DMPF_MAX_WRITE_BEHIND)
1442 DMEMIT(" max_write_behind %lu",
1443 rs->md.bitmap_info.max_write_behind);
1444
1445 if (rs->print_flags & DMPF_STRIPE_CACHE) {
1446 struct r5conf *conf = rs->md.private;
1447
1448 /* convert from kiB to sectors */
1449 DMEMIT(" stripe_cache %d",
1450 conf ? conf->max_nr_stripes * 2 : 0);
1451 }
1452
1453 if (rs->print_flags & DMPF_REGION_SIZE)
1454 DMEMIT(" region_size %lu",
1455 rs->md.bitmap_info.chunksize >> 9);
1456
1457 if (rs->print_flags & DMPF_RAID10_COPIES)
1458 DMEMIT(" raid10_copies %u",
1459 raid10_md_layout_to_copies(rs->md.layout));
1460
1461 if (rs->print_flags & DMPF_RAID10_FORMAT)
1462 DMEMIT(" raid10_format %s",
1463 raid10_md_layout_to_format(rs->md.layout));
1464
1465 DMEMIT(" %d", rs->md.raid_disks);
1466 for (i = 0; i < rs->md.raid_disks; i++) {
1467 if (rs->dev[i].meta_dev)
1468 DMEMIT(" %s", rs->dev[i].meta_dev->name);
1469 else
1470 DMEMIT(" -");
1471
1472 if (rs->dev[i].data_dev)
1473 DMEMIT(" %s", rs->dev[i].data_dev->name);
1474 else
1475 DMEMIT(" -");
1476 }
1477 }
1478}
1479
1480static int raid_message(struct dm_target *ti, unsigned argc, char **argv)
1481{
1482 struct raid_set *rs = ti->private;
1483 struct mddev *mddev = &rs->md;
1484
1485 if (!strcasecmp(argv[0], "reshape")) {
1486 DMERR("Reshape not supported.");
1487 return -EINVAL;
1488 }
1489
1490 if (!mddev->pers || !mddev->pers->sync_request)
1491 return -EINVAL;
1492
1493 if (!strcasecmp(argv[0], "frozen"))
1494 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
1495 else
1496 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
1497
1498 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
1499 if (mddev->sync_thread) {
1500 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1501 md_reap_sync_thread(mddev);
1502 }
1503 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
1504 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
1505 return -EBUSY;
1506 else if (!strcasecmp(argv[0], "resync"))
1507 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1508 else if (!strcasecmp(argv[0], "recover")) {
1509 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
1510 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1511 } else {
1512 if (!strcasecmp(argv[0], "check"))
1513 set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
1514 else if (!!strcasecmp(argv[0], "repair"))
1515 return -EINVAL;
1516 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
1517 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
1518 }
1519 if (mddev->ro == 2) {
1520 /* A write to sync_action is enough to justify
1521 * canceling read-auto mode
1522 */
1523 mddev->ro = 0;
1524 if (!mddev->suspended)
1525 md_wakeup_thread(mddev->sync_thread);
1526 }
1527 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1528 if (!mddev->suspended)
1529 md_wakeup_thread(mddev->thread);
1530
1531 return 0;
1532}
1533
1534static int raid_iterate_devices(struct dm_target *ti,
1535 iterate_devices_callout_fn fn, void *data)
1536{
1537 struct raid_set *rs = ti->private;
1538 unsigned i;
1539 int ret = 0;
1540
1541 for (i = 0; !ret && i < rs->md.raid_disks; i++)
1542 if (rs->dev[i].data_dev)
1543 ret = fn(ti,
1544 rs->dev[i].data_dev,
1545 0, /* No offset on data devs */
1546 rs->md.dev_sectors,
1547 data);
1548
1549 return ret;
1550}
1551
1552static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
1553{
1554 struct raid_set *rs = ti->private;
1555 unsigned chunk_size = rs->md.chunk_sectors << 9;
1556 struct r5conf *conf = rs->md.private;
1557
1558 blk_limits_io_min(limits, chunk_size);
1559 blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded));
1560}
1561
1562static void raid_presuspend(struct dm_target *ti)
1563{
1564 struct raid_set *rs = ti->private;
1565
1566 md_stop_writes(&rs->md);
1567}
1568
1569static void raid_postsuspend(struct dm_target *ti)
1570{
1571 struct raid_set *rs = ti->private;
1572
1573 mddev_suspend(&rs->md);
1574}
1575
1576static void attempt_restore_of_faulty_devices(struct raid_set *rs)
1577{
1578 int i;
1579 uint64_t failed_devices, cleared_failed_devices = 0;
1580 unsigned long flags;
1581 struct dm_raid_superblock *sb;
1582 struct md_rdev *r;
1583
1584 for (i = 0; i < rs->md.raid_disks; i++) {
1585 r = &rs->dev[i].rdev;
1586 if (test_bit(Faulty, &r->flags) && r->sb_page &&
1587 sync_page_io(r, 0, r->sb_size, r->sb_page, READ, 1)) {
1588 DMINFO("Faulty %s device #%d has readable super block."
1589 " Attempting to revive it.",
1590 rs->raid_type->name, i);
1591
1592 /*
1593 * Faulty bit may be set, but sometimes the array can
1594 * be suspended before the personalities can respond
1595 * by removing the device from the array (i.e. calling
1596 * 'hot_remove_disk'). If they haven't yet removed
1597 * the failed device, its 'raid_disk' number will be
1598 * '>= 0' - meaning we must call this function
1599 * ourselves.
1600 */
1601 if ((r->raid_disk >= 0) &&
1602 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0))
1603 /* Failed to revive this device, try next */
1604 continue;
1605
1606 r->raid_disk = i;
1607 r->saved_raid_disk = i;
1608 flags = r->flags;
1609 clear_bit(Faulty, &r->flags);
1610 clear_bit(WriteErrorSeen, &r->flags);
1611 clear_bit(In_sync, &r->flags);
1612 if (r->mddev->pers->hot_add_disk(r->mddev, r)) {
1613 r->raid_disk = -1;
1614 r->saved_raid_disk = -1;
1615 r->flags = flags;
1616 } else {
1617 r->recovery_offset = 0;
1618 cleared_failed_devices |= 1 << i;
1619 }
1620 }
1621 }
1622 if (cleared_failed_devices) {
1623 rdev_for_each(r, &rs->md) {
1624 sb = page_address(r->sb_page);
1625 failed_devices = le64_to_cpu(sb->failed_devices);
1626 failed_devices &= ~cleared_failed_devices;
1627 sb->failed_devices = cpu_to_le64(failed_devices);
1628 }
1629 }
1630}
1631
1632static void raid_resume(struct dm_target *ti)
1633{
1634 struct raid_set *rs = ti->private;
1635
1636 set_bit(MD_CHANGE_DEVS, &rs->md.flags);
1637 if (!rs->bitmap_loaded) {
1638 bitmap_load(&rs->md);
1639 rs->bitmap_loaded = 1;
1640 } else {
1641 /*
1642 * A secondary resume while the device is active.
1643 * Take this opportunity to check whether any failed
1644 * devices are reachable again.
1645 */
1646 attempt_restore_of_faulty_devices(rs);
1647 }
1648
1649 clear_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
1650 mddev_resume(&rs->md);
1651}
1652
1653static struct target_type raid_target = {
1654 .name = "raid",
1655 .version = {1, 5, 2},
1656 .module = THIS_MODULE,
1657 .ctr = raid_ctr,
1658 .dtr = raid_dtr,
1659 .map = raid_map,
1660 .status = raid_status,
1661 .message = raid_message,
1662 .iterate_devices = raid_iterate_devices,
1663 .io_hints = raid_io_hints,
1664 .presuspend = raid_presuspend,
1665 .postsuspend = raid_postsuspend,
1666 .resume = raid_resume,
1667};
1668
1669static int __init dm_raid_init(void)
1670{
1671 DMINFO("Loading target version %u.%u.%u",
1672 raid_target.version[0],
1673 raid_target.version[1],
1674 raid_target.version[2]);
1675 return dm_register_target(&raid_target);
1676}
1677
1678static void __exit dm_raid_exit(void)
1679{
1680 dm_unregister_target(&raid_target);
1681}
1682
1683module_init(dm_raid_init);
1684module_exit(dm_raid_exit);
1685
1686MODULE_DESCRIPTION(DM_NAME " raid4/5/6 target");
1687MODULE_ALIAS("dm-raid1");
1688MODULE_ALIAS("dm-raid10");
1689MODULE_ALIAS("dm-raid4");
1690MODULE_ALIAS("dm-raid5");
1691MODULE_ALIAS("dm-raid6");
1692MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
1693MODULE_LICENSE("GPL");