2 * Copyright (C) 2010-2011 Neil Brown
3 * Copyright (C) 2010-2016 Red Hat, Inc. All rights reserved.
5 * This file is released under the GPL.
8 #include <linux/slab.h>
9 #include <linux/module.h>
17 #include <linux/device-mapper.h>
19 #define DM_MSG_PREFIX "raid"
20 #define MAX_RAID_DEVICES 253 /* md-raid kernel limit */
23 * Minimum sectors of free reshape space per raid device
25 #define MIN_FREE_RESHAPE_SPACE to_sector(4*4096)
27 static bool devices_handle_discard_safely = false;
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.
33 #define FirstUse 10 /* rdev flag */
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
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 ------|
48 struct dm_dev *meta_dev;
49 struct dm_dev *data_dev;
54 * Bits for establishing rs->ctr_flags
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 */
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! */
77 * Flags for rs->ctr_flags field.
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)
96 * Definitions of various constructor flags to
97 * be used in checks of valid / invalid flags
100 /* Define all any sync flags */
101 #define CTR_FLAGS_ANY_SYNC (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)
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)
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)
121 /* Valid options definitions per raid level... */
123 /* "raid0" does only accept data offset */
124 #define RAID0_VALID_FLAGS (CTR_FLAG_DATA_OFFSET)
126 /* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */
127 #define RAID1_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
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)
138 /* "raid10" does not accept any raid1 or stripe cache options */
139 #define RAID10_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
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)
152 * "raid4/5/6" do not accept any raid1 or raid10 specific options
154 * "raid6" does not accept "nosync", because it is not guaranteed
155 * that both parity and q-syndrome are being written properly with
158 #define RAID45_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
160 CTR_FLAG_DAEMON_SLEEP | \
161 CTR_FLAG_MIN_RECOVERY_RATE | \
162 CTR_FLAG_MAX_RECOVERY_RATE | \
163 CTR_FLAG_MAX_WRITE_BEHIND | \
164 CTR_FLAG_STRIPE_CACHE | \
165 CTR_FLAG_REGION_SIZE | \
166 CTR_FLAG_DELTA_DISKS | \
167 CTR_FLAG_DATA_OFFSET)
169 #define RAID6_VALID_FLAGS (CTR_FLAG_SYNC | \
171 CTR_FLAG_DAEMON_SLEEP | \
172 CTR_FLAG_MIN_RECOVERY_RATE | \
173 CTR_FLAG_MAX_RECOVERY_RATE | \
174 CTR_FLAG_MAX_WRITE_BEHIND | \
175 CTR_FLAG_STRIPE_CACHE | \
176 CTR_FLAG_REGION_SIZE | \
177 CTR_FLAG_DELTA_DISKS | \
178 CTR_FLAG_DATA_OFFSET)
179 /* ...valid options definitions per raid level */
182 * Flags for rs->runtime_flags field
183 * (RT_FLAG prefix meaning "runtime flag")
185 * These are all internal and used to define runtime state,
186 * e.g. to prevent another resume from preresume processing
187 * the raid set all over again.
189 #define RT_FLAG_RS_PRERESUMED 0
190 #define RT_FLAG_RS_RESUMED 1
191 #define RT_FLAG_RS_BITMAP_LOADED 2
192 #define RT_FLAG_UPDATE_SBS 3
193 #define RT_FLAG_RESHAPE_RS 4
195 /* Array elements of 64 bit needed for rebuild/failed disk bits */
196 #define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
199 * raid set level, layout and chunk sectors backup/restore
204 int new_chunk_sectors;
208 struct dm_target *ti;
210 uint32_t bitmap_loaded;
211 uint32_t stripe_cache_entries;
212 unsigned long ctr_flags;
213 unsigned long runtime_flags;
215 uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
221 int requested_bitmap_chunk_sectors;
224 struct raid_type *raid_type;
225 struct dm_target_callbacks callbacks;
227 struct raid_dev dev[0];
230 static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)
232 struct mddev *mddev = &rs->md;
234 l->new_level = mddev->new_level;
235 l->new_layout = mddev->new_layout;
236 l->new_chunk_sectors = mddev->new_chunk_sectors;
239 static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)
241 struct mddev *mddev = &rs->md;
243 mddev->new_level = l->new_level;
244 mddev->new_layout = l->new_layout;
245 mddev->new_chunk_sectors = l->new_chunk_sectors;
248 /* raid10 algorithms (i.e. formats) */
249 #define ALGORITHM_RAID10_DEFAULT 0
250 #define ALGORITHM_RAID10_NEAR 1
251 #define ALGORITHM_RAID10_OFFSET 2
252 #define ALGORITHM_RAID10_FAR 3
254 /* Supported raid types and properties. */
255 static struct raid_type {
256 const char *name; /* RAID algorithm. */
257 const char *descr; /* Descriptor text for logging. */
258 const unsigned int parity_devs; /* # of parity devices. */
259 const unsigned int minimal_devs;/* minimal # of devices in set. */
260 const unsigned int level; /* RAID level. */
261 const unsigned int algorithm; /* RAID algorithm. */
263 {"raid0", "raid0 (striping)", 0, 2, 0, 0 /* NONE */},
264 {"raid1", "raid1 (mirroring)", 0, 2, 1, 0 /* NONE */},
265 {"raid10_far", "raid10 far (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_FAR},
266 {"raid10_offset", "raid10 offset (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_OFFSET},
267 {"raid10_near", "raid10 near (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_NEAR},
268 {"raid10", "raid10 (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_DEFAULT},
269 {"raid4", "raid4 (dedicated last parity disk)", 1, 2, 4, ALGORITHM_PARITY_N}, /* raid4 layout = raid5_n */
270 {"raid5_n", "raid5 (dedicated last parity disk)", 1, 2, 5, ALGORITHM_PARITY_N},
271 {"raid5_ls", "raid5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC},
272 {"raid5_rs", "raid5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC},
273 {"raid5_la", "raid5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC},
274 {"raid5_ra", "raid5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC},
275 {"raid6_zr", "raid6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART},
276 {"raid6_nr", "raid6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART},
277 {"raid6_nc", "raid6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE},
278 {"raid6_n_6", "raid6 (dedicated parity/Q n/6)", 2, 4, 6, ALGORITHM_PARITY_N_6},
279 {"raid6_ls_6", "raid6 (left symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_SYMMETRIC_6},
280 {"raid6_rs_6", "raid6 (right symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_SYMMETRIC_6},
281 {"raid6_la_6", "raid6 (left asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_ASYMMETRIC_6},
282 {"raid6_ra_6", "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_ASYMMETRIC_6}
285 /* True, if @v is in inclusive range [@min, @max] */
286 static bool __within_range(long v, long min, long max)
288 return v >= min && v <= max;
291 /* All table line arguments are defined here */
292 static struct arg_name_flag {
293 const unsigned long flag;
295 } __arg_name_flags[] = {
296 { CTR_FLAG_SYNC, "sync"},
297 { CTR_FLAG_NOSYNC, "nosync"},
298 { CTR_FLAG_REBUILD, "rebuild"},
299 { CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
300 { CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
301 { CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
302 { CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
303 { CTR_FLAG_WRITE_MOSTLY, "write_mostly"},
304 { CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
305 { CTR_FLAG_REGION_SIZE, "region_size"},
306 { CTR_FLAG_RAID10_COPIES, "raid10_copies"},
307 { CTR_FLAG_RAID10_FORMAT, "raid10_format"},
308 { CTR_FLAG_DATA_OFFSET, "data_offset"},
309 { CTR_FLAG_DELTA_DISKS, "delta_disks"},
310 { CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
313 /* Return argument name string for given @flag */
314 static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
316 if (hweight32(flag) == 1) {
317 struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
319 while (anf-- > __arg_name_flags)
320 if (flag & anf->flag)
324 DMERR("%s called with more than one flag!", __func__);
330 * Bool helpers to test for various raid levels of a raid set.
331 * It's level as reported by the superblock rather than
332 * the requested raid_type passed to the constructor.
334 /* Return true, if raid set in @rs is raid0 */
335 static bool rs_is_raid0(struct raid_set *rs)
337 return !rs->md.level;
340 /* Return true, if raid set in @rs is raid1 */
341 static bool rs_is_raid1(struct raid_set *rs)
343 return rs->md.level == 1;
346 /* Return true, if raid set in @rs is raid10 */
347 static bool rs_is_raid10(struct raid_set *rs)
349 return rs->md.level == 10;
352 /* Return true, if raid set in @rs is level 6 */
353 static bool rs_is_raid6(struct raid_set *rs)
355 return rs->md.level == 6;
358 /* Return true, if raid set in @rs is level 4, 5 or 6 */
359 static bool rs_is_raid456(struct raid_set *rs)
361 return __within_range(rs->md.level, 4, 6);
364 /* Return true, if raid set in @rs is reshapable */
365 static bool __is_raid10_far(int layout);
366 static bool rs_is_reshapable(struct raid_set *rs)
368 return rs_is_raid456(rs) ||
369 (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
372 /* Return true, if raid set in @rs is recovering */
373 static bool rs_is_recovering(struct raid_set *rs)
375 return rs->md.recovery_cp < rs->dev[0].rdev.sectors;
378 /* Return true, if raid set in @rs is reshaping */
379 static bool rs_is_reshaping(struct raid_set *rs)
381 return rs->md.reshape_position != MaxSector;
385 * bool helpers to test for various raid levels of a raid type @rt
388 /* Return true, if raid type in @rt is raid0 */
389 static bool rt_is_raid0(struct raid_type *rt)
394 /* Return true, if raid type in @rt is raid1 */
395 static bool rt_is_raid1(struct raid_type *rt)
397 return rt->level == 1;
400 /* Return true, if raid type in @rt is raid10 */
401 static bool rt_is_raid10(struct raid_type *rt)
403 return rt->level == 10;
406 /* Return true, if raid type in @rt is raid4/5 */
407 static bool rt_is_raid45(struct raid_type *rt)
409 return __within_range(rt->level, 4, 5);
412 /* Return true, if raid type in @rt is raid6 */
413 static bool rt_is_raid6(struct raid_type *rt)
415 return rt->level == 6;
418 /* Return true, if raid type in @rt is raid4/5/6 */
419 static bool rt_is_raid456(struct raid_type *rt)
421 return __within_range(rt->level, 4, 6);
423 /* END: raid level bools */
425 /* Return valid ctr flags for the raid level of @rs */
426 static unsigned long __valid_flags(struct raid_set *rs)
428 if (rt_is_raid0(rs->raid_type))
429 return RAID0_VALID_FLAGS;
430 else if (rt_is_raid1(rs->raid_type))
431 return RAID1_VALID_FLAGS;
432 else if (rt_is_raid10(rs->raid_type))
433 return RAID10_VALID_FLAGS;
434 else if (rt_is_raid45(rs->raid_type))
435 return RAID45_VALID_FLAGS;
436 else if (rt_is_raid6(rs->raid_type))
437 return RAID6_VALID_FLAGS;
443 * Check for valid flags set on @rs
445 * Has to be called after parsing of the ctr flags!
447 static int rs_check_for_valid_flags(struct raid_set *rs)
449 if (rs->ctr_flags & ~__valid_flags(rs)) {
450 rs->ti->error = "Invalid flags combination";
457 /* MD raid10 bit definitions and helpers */
458 #define RAID10_OFFSET (1 << 16) /* stripes with data copies area adjacent on devices */
459 #define RAID10_BROCKEN_USE_FAR_SETS (1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
460 #define RAID10_USE_FAR_SETS (1 << 18) /* Use sets instead of whole stripe rotation */
461 #define RAID10_FAR_COPIES_SHIFT 8 /* raid10 # far copies shift (2nd byte of layout) */
463 /* Return md raid10 near copies for @layout */
464 static unsigned int __raid10_near_copies(int layout)
466 return layout & 0xFF;
469 /* Return md raid10 far copies for @layout */
470 static unsigned int __raid10_far_copies(int layout)
472 return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
475 /* Return true if md raid10 offset for @layout */
476 static bool __is_raid10_offset(int layout)
478 return !!(layout & RAID10_OFFSET);
481 /* Return true if md raid10 near for @layout */
482 static bool __is_raid10_near(int layout)
484 return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
487 /* Return true if md raid10 far for @layout */
488 static bool __is_raid10_far(int layout)
490 return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
493 /* Return md raid10 layout string for @layout */
494 static const char *raid10_md_layout_to_format(int layout)
497 * Bit 16 stands for "offset"
498 * (i.e. adjacent stripes hold copies)
500 * Refer to MD's raid10.c for details
502 if (__is_raid10_offset(layout))
505 if (__raid10_near_copies(layout) > 1)
508 WARN_ON(__raid10_far_copies(layout) < 2);
513 /* Return md raid10 algorithm for @name */
514 static int raid10_name_to_format(const char *name)
516 if (!strcasecmp(name, "near"))
517 return ALGORITHM_RAID10_NEAR;
518 else if (!strcasecmp(name, "offset"))
519 return ALGORITHM_RAID10_OFFSET;
520 else if (!strcasecmp(name, "far"))
521 return ALGORITHM_RAID10_FAR;
526 /* Return md raid10 copies for @layout */
527 static unsigned int raid10_md_layout_to_copies(int layout)
529 return max(__raid10_near_copies(layout), __raid10_far_copies(layout));
532 /* Return md raid10 format id for @format string */
533 static int raid10_format_to_md_layout(struct raid_set *rs,
534 unsigned int algorithm,
537 unsigned int n = 1, f = 1, r = 0;
540 * MD resilienece flaw:
542 * enabling use_far_sets for far/offset formats causes copies
543 * to be colocated on the same devs together with their origins!
545 * -> disable it for now in the definition above
547 if (algorithm == ALGORITHM_RAID10_DEFAULT ||
548 algorithm == ALGORITHM_RAID10_NEAR)
551 else if (algorithm == ALGORITHM_RAID10_OFFSET) {
554 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
555 r |= RAID10_USE_FAR_SETS;
557 } else if (algorithm == ALGORITHM_RAID10_FAR) {
560 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
561 r |= RAID10_USE_FAR_SETS;
566 return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
568 /* END: MD raid10 bit definitions and helpers */
570 /* Check for any of the raid10 algorithms */
571 static bool __got_raid10(struct raid_type *rtp, const int layout)
573 if (rtp->level == 10) {
574 switch (rtp->algorithm) {
575 case ALGORITHM_RAID10_DEFAULT:
576 case ALGORITHM_RAID10_NEAR:
577 return __is_raid10_near(layout);
578 case ALGORITHM_RAID10_OFFSET:
579 return __is_raid10_offset(layout);
580 case ALGORITHM_RAID10_FAR:
581 return __is_raid10_far(layout);
590 /* Return raid_type for @name */
591 static struct raid_type *get_raid_type(const char *name)
593 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
595 while (rtp-- > raid_types)
596 if (!strcasecmp(rtp->name, name))
602 /* Return raid_type for @name based derived from @level and @layout */
603 static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
605 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
607 while (rtp-- > raid_types) {
608 /* RAID10 special checks based on @layout flags/properties */
609 if (rtp->level == level &&
610 (__got_raid10(rtp, layout) || rtp->algorithm == layout))
618 * Conditionally change bdev capacity of @rs
619 * in case of a disk add/remove reshape
621 static void rs_set_capacity(struct raid_set *rs)
623 struct mddev *mddev = &rs->md;
624 struct md_rdev *rdev;
625 struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
628 * raid10 sets rdev->sector to the device size, which
629 * is unintended in case of out-of-place reshaping
631 rdev_for_each(rdev, mddev)
632 rdev->sectors = mddev->dev_sectors;
634 set_capacity(gendisk, mddev->array_sectors);
635 revalidate_disk(gendisk);
639 * Set the mddev properties in @rs to the current
640 * ones retrieved from the freshest superblock
642 static void rs_set_cur(struct raid_set *rs)
644 struct mddev *mddev = &rs->md;
646 mddev->new_level = mddev->level;
647 mddev->new_layout = mddev->layout;
648 mddev->new_chunk_sectors = mddev->chunk_sectors;
652 * Set the mddev properties in @rs to the new
653 * ones requested by the ctr
655 static void rs_set_new(struct raid_set *rs)
657 struct mddev *mddev = &rs->md;
659 mddev->level = mddev->new_level;
660 mddev->layout = mddev->new_layout;
661 mddev->chunk_sectors = mddev->new_chunk_sectors;
662 mddev->raid_disks = rs->raid_disks;
663 mddev->delta_disks = 0;
666 static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
667 unsigned int raid_devs)
672 if (raid_devs <= raid_type->parity_devs) {
673 ti->error = "Insufficient number of devices";
674 return ERR_PTR(-EINVAL);
677 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL);
679 ti->error = "Cannot allocate raid context";
680 return ERR_PTR(-ENOMEM);
685 rs->raid_disks = raid_devs;
689 rs->raid_type = raid_type;
690 rs->stripe_cache_entries = 256;
691 rs->md.raid_disks = raid_devs;
692 rs->md.level = raid_type->level;
693 rs->md.new_level = rs->md.level;
694 rs->md.layout = raid_type->algorithm;
695 rs->md.new_layout = rs->md.layout;
696 rs->md.delta_disks = 0;
697 rs->md.recovery_cp = MaxSector;
699 for (i = 0; i < raid_devs; i++)
700 md_rdev_init(&rs->dev[i].rdev);
703 * Remaining items to be initialized by further RAID params:
706 * rs->md.chunk_sectors
707 * rs->md.new_chunk_sectors
714 static void raid_set_free(struct raid_set *rs)
718 for (i = 0; i < rs->raid_disks; i++) {
719 if (rs->dev[i].meta_dev)
720 dm_put_device(rs->ti, rs->dev[i].meta_dev);
721 md_rdev_clear(&rs->dev[i].rdev);
722 if (rs->dev[i].data_dev)
723 dm_put_device(rs->ti, rs->dev[i].data_dev);
730 * For every device we have two words
731 * <meta_dev>: meta device name or '-' if missing
732 * <data_dev>: data device name or '-' if missing
734 * The following are permitted:
737 * <meta_dev> <data_dev>
739 * The following is not allowed:
742 * This code parses those words. If there is a failure,
743 * the caller must use raid_set_free() to unwind the operations.
745 static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
749 int metadata_available = 0;
753 /* Put off the number of raid devices argument to get to dev pairs */
754 arg = dm_shift_arg(as);
758 for (i = 0; i < rs->raid_disks; i++) {
759 rs->dev[i].rdev.raid_disk = i;
761 rs->dev[i].meta_dev = NULL;
762 rs->dev[i].data_dev = NULL;
765 * There are no offsets, since there is a separate device
766 * for data and metadata.
768 rs->dev[i].rdev.data_offset = 0;
769 rs->dev[i].rdev.mddev = &rs->md;
771 arg = dm_shift_arg(as);
775 if (strcmp(arg, "-")) {
776 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
777 &rs->dev[i].meta_dev);
779 rs->ti->error = "RAID metadata device lookup failure";
783 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
784 if (!rs->dev[i].rdev.sb_page) {
785 rs->ti->error = "Failed to allocate superblock page";
790 arg = dm_shift_arg(as);
794 if (!strcmp(arg, "-")) {
795 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
796 (!rs->dev[i].rdev.recovery_offset)) {
797 rs->ti->error = "Drive designated for rebuild not specified";
801 if (rs->dev[i].meta_dev) {
802 rs->ti->error = "No data device supplied with metadata device";
809 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
810 &rs->dev[i].data_dev);
812 rs->ti->error = "RAID device lookup failure";
816 if (rs->dev[i].meta_dev) {
817 metadata_available = 1;
818 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
820 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
821 list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
822 if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
826 if (metadata_available) {
828 rs->md.persistent = 1;
829 rs->md.major_version = 2;
830 } else if (rebuild && !rs->md.recovery_cp) {
832 * Without metadata, we will not be able to tell if the array
833 * is in-sync or not - we must assume it is not. Therefore,
834 * it is impossible to rebuild a drive.
836 * Even if there is metadata, the on-disk information may
837 * indicate that the array is not in-sync and it will then
840 * User could specify 'nosync' option if desperate.
842 rs->ti->error = "Unable to rebuild drive while array is not in-sync";
850 * validate_region_size
852 * @region_size: region size in sectors. If 0, pick a size (4MiB default).
854 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
855 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
857 * Returns: 0 on success, -EINVAL on failure.
859 static int validate_region_size(struct raid_set *rs, unsigned long region_size)
861 unsigned long min_region_size = rs->ti->len / (1 << 21);
865 * Choose a reasonable default. All figures in sectors.
867 if (min_region_size > (1 << 13)) {
868 /* If not a power of 2, make it the next power of 2 */
869 region_size = roundup_pow_of_two(min_region_size);
870 DMINFO("Choosing default region size of %lu sectors",
873 DMINFO("Choosing default region size of 4MiB");
874 region_size = 1 << 13; /* sectors */
878 * Validate user-supplied value.
880 if (region_size > rs->ti->len) {
881 rs->ti->error = "Supplied region size is too large";
885 if (region_size < min_region_size) {
886 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
887 region_size, min_region_size);
888 rs->ti->error = "Supplied region size is too small";
892 if (!is_power_of_2(region_size)) {
893 rs->ti->error = "Region size is not a power of 2";
897 if (region_size < rs->md.chunk_sectors) {
898 rs->ti->error = "Region size is smaller than the chunk size";
904 * Convert sectors to bytes.
906 rs->md.bitmap_info.chunksize = to_bytes(region_size);
912 * validate_raid_redundancy
915 * Determine if there are enough devices in the array that haven't
916 * failed (or are being rebuilt) to form a usable array.
918 * Returns: 0 on success, -EINVAL on failure.
920 static int validate_raid_redundancy(struct raid_set *rs)
922 unsigned int i, rebuild_cnt = 0;
923 unsigned int rebuilds_per_group = 0, copies;
924 unsigned int group_size, last_group_start;
926 for (i = 0; i < rs->md.raid_disks; i++)
927 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
928 !rs->dev[i].rdev.sb_page)
931 switch (rs->raid_type->level) {
933 if (rebuild_cnt >= rs->md.raid_disks)
939 if (rebuild_cnt > rs->raid_type->parity_devs)
943 copies = raid10_md_layout_to_copies(rs->md.new_layout);
944 if (rebuild_cnt < copies)
948 * It is possible to have a higher rebuild count for RAID10,
949 * as long as the failed devices occur in different mirror
950 * groups (i.e. different stripes).
952 * When checking "near" format, make sure no adjacent devices
953 * have failed beyond what can be handled. In addition to the
954 * simple case where the number of devices is a multiple of the
955 * number of copies, we must also handle cases where the number
956 * of devices is not a multiple of the number of copies.
957 * E.g. dev1 dev2 dev3 dev4 dev5
961 if (__is_raid10_near(rs->md.new_layout)) {
962 for (i = 0; i < rs->md.raid_disks; i++) {
964 rebuilds_per_group = 0;
965 if ((!rs->dev[i].rdev.sb_page ||
966 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
967 (++rebuilds_per_group >= copies))
974 * When checking "far" and "offset" formats, we need to ensure
975 * that the device that holds its copy is not also dead or
976 * being rebuilt. (Note that "far" and "offset" formats only
977 * support two copies right now. These formats also only ever
978 * use the 'use_far_sets' variant.)
980 * This check is somewhat complicated by the need to account
981 * for arrays that are not a multiple of (far) copies. This
982 * results in the need to treat the last (potentially larger)
985 group_size = (rs->md.raid_disks / copies);
986 last_group_start = (rs->md.raid_disks / group_size) - 1;
987 last_group_start *= group_size;
988 for (i = 0; i < rs->md.raid_disks; i++) {
989 if (!(i % copies) && !(i > last_group_start))
990 rebuilds_per_group = 0;
991 if ((!rs->dev[i].rdev.sb_page ||
992 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
993 (++rebuilds_per_group >= copies))
1009 * Possible arguments are...
1010 * <chunk_size> [optional_args]
1012 * Argument definitions
1013 * <chunk_size> The number of sectors per disk that
1014 * will form the "stripe"
1015 * [[no]sync] Force or prevent recovery of the
1017 * [rebuild <idx>] Rebuild the drive indicated by the index
1018 * [daemon_sleep <ms>] Time between bitmap daemon work to
1020 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1021 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1022 * [write_mostly <idx>] Indicate a write mostly drive via index
1023 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
1024 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs
1025 * [region_size <sectors>] Defines granularity of bitmap
1027 * RAID10-only options:
1028 * [raid10_copies <# copies>] Number of copies. (Default: 2)
1029 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
1031 static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
1032 unsigned int num_raid_params)
1034 int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
1035 unsigned int raid10_copies = 2;
1036 unsigned int i, write_mostly = 0;
1037 unsigned int region_size = 0;
1038 sector_t max_io_len;
1039 const char *arg, *key;
1040 struct raid_dev *rd;
1041 struct raid_type *rt = rs->raid_type;
1043 arg = dm_shift_arg(as);
1044 num_raid_params--; /* Account for chunk_size argument */
1046 if (kstrtoint(arg, 10, &value) < 0) {
1047 rs->ti->error = "Bad numerical argument given for chunk_size";
1052 * First, parse the in-order required arguments
1053 * "chunk_size" is the only argument of this type.
1055 if (rt_is_raid1(rt)) {
1057 DMERR("Ignoring chunk size parameter for RAID 1");
1059 } else if (!is_power_of_2(value)) {
1060 rs->ti->error = "Chunk size must be a power of 2";
1062 } else if (value < 8) {
1063 rs->ti->error = "Chunk size value is too small";
1067 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1070 * We set each individual device as In_sync with a completed
1071 * 'recovery_offset'. If there has been a device failure or
1072 * replacement then one of the following cases applies:
1074 * 1) User specifies 'rebuild'.
1075 * - Device is reset when param is read.
1076 * 2) A new device is supplied.
1077 * - No matching superblock found, resets device.
1078 * 3) Device failure was transient and returns on reload.
1079 * - Failure noticed, resets device for bitmap replay.
1080 * 4) Device hadn't completed recovery after previous failure.
1081 * - Superblock is read and overrides recovery_offset.
1083 * What is found in the superblocks of the devices is always
1084 * authoritative, unless 'rebuild' or '[no]sync' was specified.
1086 for (i = 0; i < rs->raid_disks; i++) {
1087 set_bit(In_sync, &rs->dev[i].rdev.flags);
1088 rs->dev[i].rdev.recovery_offset = MaxSector;
1092 * Second, parse the unordered optional arguments
1094 for (i = 0; i < num_raid_params; i++) {
1095 key = dm_shift_arg(as);
1097 rs->ti->error = "Not enough raid parameters given";
1101 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1102 if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1103 rs->ti->error = "Only one 'nosync' argument allowed";
1108 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1109 if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1110 rs->ti->error = "Only one 'sync' argument allowed";
1115 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1116 if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1117 rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1123 arg = dm_shift_arg(as);
1124 i++; /* Account for the argument pairs */
1126 rs->ti->error = "Wrong number of raid parameters given";
1131 * Parameters that take a string value are checked here.
1134 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1135 if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1136 rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1139 if (!rt_is_raid10(rt)) {
1140 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1143 raid10_format = raid10_name_to_format(arg);
1144 if (raid10_format < 0) {
1145 rs->ti->error = "Invalid 'raid10_format' value given";
1146 return raid10_format;
1151 if (kstrtoint(arg, 10, &value) < 0) {
1152 rs->ti->error = "Bad numerical argument given in raid params";
1156 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1158 * "rebuild" is being passed in by userspace to provide
1159 * indexes of replaced devices and to set up additional
1160 * devices on raid level takeover.
1162 if (!__within_range(value, 0, rs->raid_disks - 1)) {
1163 rs->ti->error = "Invalid rebuild index given";
1167 if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1168 rs->ti->error = "rebuild for this index already given";
1172 rd = rs->dev + value;
1173 clear_bit(In_sync, &rd->rdev.flags);
1174 clear_bit(Faulty, &rd->rdev.flags);
1175 rd->rdev.recovery_offset = 0;
1176 set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1177 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1178 if (!rt_is_raid1(rt)) {
1179 rs->ti->error = "write_mostly option is only valid for RAID1";
1183 if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1184 rs->ti->error = "Invalid write_mostly index given";
1189 set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1190 set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1191 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1192 if (!rt_is_raid1(rt)) {
1193 rs->ti->error = "max_write_behind option is only valid for RAID1";
1197 if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1198 rs->ti->error = "Only one max_write_behind argument pair allowed";
1203 * In device-mapper, we specify things in sectors, but
1204 * MD records this value in kB
1207 if (value > COUNTER_MAX) {
1208 rs->ti->error = "Max write-behind limit out of range";
1212 rs->md.bitmap_info.max_write_behind = value;
1213 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1214 if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1215 rs->ti->error = "Only one daemon_sleep argument pair allowed";
1218 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
1219 rs->ti->error = "daemon sleep period out of range";
1222 rs->md.bitmap_info.daemon_sleep = value;
1223 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1224 /* Userspace passes new data_offset after having extended the the data image LV */
1225 if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1226 rs->ti->error = "Only one data_offset argument pair allowed";
1229 /* Ensure sensible data offset */
1231 (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {
1232 rs->ti->error = "Bogus data_offset value";
1235 rs->data_offset = value;
1236 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1237 /* Define the +/-# of disks to add to/remove from the given raid set */
1238 if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1239 rs->ti->error = "Only one delta_disks argument pair allowed";
1242 /* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1243 if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1244 rs->ti->error = "Too many delta_disk requested";
1248 rs->delta_disks = value;
1249 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1250 if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1251 rs->ti->error = "Only one stripe_cache argument pair allowed";
1255 if (!rt_is_raid456(rt)) {
1256 rs->ti->error = "Inappropriate argument: stripe_cache";
1260 rs->stripe_cache_entries = value;
1261 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1262 if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1263 rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1266 if (value > INT_MAX) {
1267 rs->ti->error = "min_recovery_rate out of range";
1270 rs->md.sync_speed_min = (int)value;
1271 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1272 if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
1273 rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1276 if (value > INT_MAX) {
1277 rs->ti->error = "max_recovery_rate out of range";
1280 rs->md.sync_speed_max = (int)value;
1281 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1282 if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1283 rs->ti->error = "Only one region_size argument pair allowed";
1287 region_size = value;
1288 rs->requested_bitmap_chunk_sectors = value;
1289 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1290 if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1291 rs->ti->error = "Only one raid10_copies argument pair allowed";
1295 if (!__within_range(value, 2, rs->md.raid_disks)) {
1296 rs->ti->error = "Bad value for 'raid10_copies'";
1300 raid10_copies = value;
1302 DMERR("Unable to parse RAID parameter: %s", key);
1303 rs->ti->error = "Unable to parse RAID parameter";
1308 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1309 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1310 rs->ti->error = "sync and nosync are mutually exclusive";
1314 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
1315 (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
1316 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
1317 rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
1321 if (write_mostly >= rs->md.raid_disks) {
1322 rs->ti->error = "Can't set all raid1 devices to write_mostly";
1326 if (validate_region_size(rs, region_size))
1329 if (rs->md.chunk_sectors)
1330 max_io_len = rs->md.chunk_sectors;
1332 max_io_len = region_size;
1334 if (dm_set_target_max_io_len(rs->ti, max_io_len))
1337 if (rt_is_raid10(rt)) {
1338 if (raid10_copies > rs->md.raid_disks) {
1339 rs->ti->error = "Not enough devices to satisfy specification";
1343 rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1344 if (rs->md.new_layout < 0) {
1345 rs->ti->error = "Error getting raid10 format";
1346 return rs->md.new_layout;
1349 rt = get_raid_type_by_ll(10, rs->md.new_layout);
1351 rs->ti->error = "Failed to recognize new raid10 layout";
1355 if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1356 rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1357 test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1358 rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1363 rs->raid10_copies = raid10_copies;
1365 /* Assume there are no metadata devices until the drives are parsed */
1366 rs->md.persistent = 0;
1367 rs->md.external = 1;
1369 /* Check, if any invalid ctr arguments have been passed in for the raid level */
1370 return rs_check_for_valid_flags(rs);
1373 /* Set raid4/5/6 cache size */
1374 static int rs_set_raid456_stripe_cache(struct raid_set *rs)
1377 struct r5conf *conf;
1378 struct mddev *mddev = &rs->md;
1379 uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
1380 uint32_t nr_stripes = rs->stripe_cache_entries;
1382 if (!rt_is_raid456(rs->raid_type)) {
1383 rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
1387 if (nr_stripes < min_stripes) {
1388 DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
1389 nr_stripes, min_stripes);
1390 nr_stripes = min_stripes;
1393 conf = mddev->private;
1395 rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
1399 /* Try setting number of stripes in raid456 stripe cache */
1400 if (conf->min_nr_stripes != nr_stripes) {
1401 r = raid5_set_cache_size(mddev, nr_stripes);
1403 rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
1407 DMINFO("%u stripe cache entries", nr_stripes);
1413 /* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1414 static unsigned int mddev_data_stripes(struct raid_set *rs)
1416 return rs->md.raid_disks - rs->raid_type->parity_devs;
1419 /* Return # of data stripes of @rs (i.e. as of ctr) */
1420 static unsigned int rs_data_stripes(struct raid_set *rs)
1422 return rs->raid_disks - rs->raid_type->parity_devs;
1425 /* Calculate the sectors per device and per array used for @rs */
1426 static int rs_set_dev_and_array_sectors(struct raid_set *rs, bool use_mddev)
1429 unsigned int data_stripes;
1430 struct mddev *mddev = &rs->md;
1431 struct md_rdev *rdev;
1432 sector_t array_sectors = rs->ti->len, dev_sectors = rs->ti->len;
1435 delta_disks = mddev->delta_disks;
1436 data_stripes = mddev_data_stripes(rs);
1438 delta_disks = rs->delta_disks;
1439 data_stripes = rs_data_stripes(rs);
1442 /* Special raid1 case w/o delta_disks support (yet) */
1443 if (rt_is_raid1(rs->raid_type))
1445 else if (rt_is_raid10(rs->raid_type)) {
1446 if (rs->raid10_copies < 2 ||
1448 rs->ti->error = "Bogus raid10 data copies or delta disks";
1452 dev_sectors *= rs->raid10_copies;
1453 if (sector_div(dev_sectors, data_stripes))
1456 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1457 if (sector_div(array_sectors, rs->raid10_copies))
1460 } else if (sector_div(dev_sectors, data_stripes))
1464 /* Striped layouts */
1465 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1467 rdev_for_each(rdev, mddev)
1468 rdev->sectors = dev_sectors;
1470 mddev->array_sectors = array_sectors;
1471 mddev->dev_sectors = dev_sectors;
1475 rs->ti->error = "Target length not divisible by number of data devices";
1479 /* Setup recovery on @rs */
1480 static void __rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1482 /* raid0 does not recover */
1483 if (rs_is_raid0(rs))
1484 rs->md.recovery_cp = MaxSector;
1486 * A raid6 set has to be recovered either
1487 * completely or for the grown part to
1488 * ensure proper parity and Q-Syndrome
1490 else if (rs_is_raid6(rs))
1491 rs->md.recovery_cp = dev_sectors;
1493 * Other raid set types may skip recovery
1494 * depending on the 'nosync' flag.
1497 rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
1498 ? MaxSector : dev_sectors;
1501 /* Setup recovery on @rs based on raid type, device size and 'nosync' flag */
1502 static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1505 /* New raid set or 'sync' flag provided */
1506 __rs_setup_recovery(rs, 0);
1507 else if (dev_sectors == MaxSector)
1508 /* Prevent recovery */
1509 __rs_setup_recovery(rs, MaxSector);
1510 else if (rs->dev[0].rdev.sectors < dev_sectors)
1511 /* Grown raid set */
1512 __rs_setup_recovery(rs, rs->dev[0].rdev.sectors);
1514 __rs_setup_recovery(rs, MaxSector);
1517 static void do_table_event(struct work_struct *ws)
1519 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1521 smp_rmb(); /* Make sure we access most actual mddev properties */
1522 if (!rs_is_reshaping(rs))
1523 rs_set_capacity(rs);
1524 dm_table_event(rs->ti->table);
1527 static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
1529 struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
1531 return mddev_congested(&rs->md, bits);
1535 * Make sure a valid takover (level switch) is being requested on @rs
1537 * Conversions of raid sets from one MD personality to another
1538 * have to conform to restrictions which are enforced here.
1540 static int rs_check_takeover(struct raid_set *rs)
1542 struct mddev *mddev = &rs->md;
1543 unsigned int near_copies;
1545 if (rs->md.degraded) {
1546 rs->ti->error = "Can't takeover degraded raid set";
1550 if (rs_is_reshaping(rs)) {
1551 rs->ti->error = "Can't takeover reshaping raid set";
1555 switch (mddev->level) {
1557 /* raid0 -> raid1/5 with one disk */
1558 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1559 mddev->raid_disks == 1)
1562 /* raid0 -> raid10 */
1563 if (mddev->new_level == 10 &&
1564 !(rs->raid_disks % mddev->raid_disks))
1567 /* raid0 with multiple disks -> raid4/5/6 */
1568 if (__within_range(mddev->new_level, 4, 6) &&
1569 mddev->new_layout == ALGORITHM_PARITY_N &&
1570 mddev->raid_disks > 1)
1576 /* Can't takeover raid10_offset! */
1577 if (__is_raid10_offset(mddev->layout))
1580 near_copies = __raid10_near_copies(mddev->layout);
1582 /* raid10* -> raid0 */
1583 if (mddev->new_level == 0) {
1584 /* Can takeover raid10_near with raid disks divisable by data copies! */
1585 if (near_copies > 1 &&
1586 !(mddev->raid_disks % near_copies)) {
1587 mddev->raid_disks /= near_copies;
1588 mddev->delta_disks = mddev->raid_disks;
1592 /* Can takeover raid10_far */
1593 if (near_copies == 1 &&
1594 __raid10_far_copies(mddev->layout) > 1)
1600 /* raid10_{near,far} -> raid1 */
1601 if (mddev->new_level == 1 &&
1602 max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1605 /* raid10_{near,far} with 2 disks -> raid4/5 */
1606 if (__within_range(mddev->new_level, 4, 5) &&
1607 mddev->raid_disks == 2)
1612 /* raid1 with 2 disks -> raid4/5 */
1613 if (__within_range(mddev->new_level, 4, 5) &&
1614 mddev->raid_disks == 2) {
1615 mddev->degraded = 1;
1619 /* raid1 -> raid0 */
1620 if (mddev->new_level == 0 &&
1621 mddev->raid_disks == 1)
1624 /* raid1 -> raid10 */
1625 if (mddev->new_level == 10)
1630 /* raid4 -> raid0 */
1631 if (mddev->new_level == 0)
1634 /* raid4 -> raid1/5 with 2 disks */
1635 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1636 mddev->raid_disks == 2)
1639 /* raid4 -> raid5/6 with parity N */
1640 if (__within_range(mddev->new_level, 5, 6) &&
1641 mddev->layout == ALGORITHM_PARITY_N)
1646 /* raid5 with parity N -> raid0 */
1647 if (mddev->new_level == 0 &&
1648 mddev->layout == ALGORITHM_PARITY_N)
1651 /* raid5 with parity N -> raid4 */
1652 if (mddev->new_level == 4 &&
1653 mddev->layout == ALGORITHM_PARITY_N)
1656 /* raid5 with 2 disks -> raid1/4/10 */
1657 if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1658 mddev->raid_disks == 2)
1661 /* raid5_* -> raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
1662 if (mddev->new_level == 6 &&
1663 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1664 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1669 /* raid6 with parity N -> raid0 */
1670 if (mddev->new_level == 0 &&
1671 mddev->layout == ALGORITHM_PARITY_N)
1674 /* raid6 with parity N -> raid4 */
1675 if (mddev->new_level == 4 &&
1676 mddev->layout == ALGORITHM_PARITY_N)
1679 /* raid6_*_n with Q-Syndrome N -> raid5_* */
1680 if (mddev->new_level == 5 &&
1681 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1682 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1689 rs->ti->error = "takeover not possible";
1693 /* True if @rs requested to be taken over */
1694 static bool rs_takeover_requested(struct raid_set *rs)
1696 return rs->md.new_level != rs->md.level;
1699 /* True if @rs is requested to reshape by ctr */
1700 static bool rs_reshape_requested(struct raid_set *rs)
1703 struct mddev *mddev = &rs->md;
1705 if (rs_takeover_requested(rs))
1711 change = mddev->new_layout != mddev->layout ||
1712 mddev->new_chunk_sectors != mddev->chunk_sectors ||
1715 /* Historical case to support raid1 reshape without delta disks */
1716 if (mddev->level == 1) {
1717 if (rs->delta_disks)
1718 return !!rs->delta_disks;
1721 mddev->raid_disks != rs->raid_disks;
1724 if (mddev->level == 10)
1726 !__is_raid10_far(mddev->new_layout) &&
1727 rs->delta_disks >= 0;
1733 #define FEATURE_FLAG_SUPPORTS_V190 0x1 /* Supports extended superblock */
1735 /* State flags for sb->flags */
1736 #define SB_FLAG_RESHAPE_ACTIVE 0x1
1737 #define SB_FLAG_RESHAPE_BACKWARDS 0x2
1740 * This structure is never routinely used by userspace, unlike md superblocks.
1741 * Devices with this superblock should only ever be accessed via device-mapper.
1743 #define DM_RAID_MAGIC 0x64526D44
1744 struct dm_raid_superblock {
1745 __le32 magic; /* "DmRd" */
1746 __le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1748 __le32 num_devices; /* Number of devices in this raid set. (Max 64) */
1749 __le32 array_position; /* The position of this drive in the raid set */
1751 __le64 events; /* Incremented by md when superblock updated */
1752 __le64 failed_devices; /* Pre 1.9.0 part of bit field of devices to */
1753 /* indicate failures (see extension below) */
1756 * This offset tracks the progress of the repair or replacement of
1757 * an individual drive.
1759 __le64 disk_recovery_offset;
1762 * This offset tracks the progress of the initial raid set
1763 * synchronisation/parity calculation.
1765 __le64 array_resync_offset;
1768 * raid characteristics
1772 __le32 stripe_sectors;
1774 /********************************************************************
1775 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1777 * FEATURE_FLAG_SUPPORTS_V190 in the features member indicates that those exist
1780 __le32 flags; /* Flags defining array states for reshaping */
1783 * This offset tracks the progress of a raid
1784 * set reshape in order to be able to restart it
1786 __le64 reshape_position;
1789 * These define the properties of the array in case of an interrupted reshape
1793 __le32 new_stripe_sectors;
1796 __le64 array_sectors; /* Array size in sectors */
1799 * Sector offsets to data on devices (reshaping).
1800 * Needed to support out of place reshaping, thus
1801 * not writing over any stripes whilst converting
1802 * them from old to new layout
1805 __le64 new_data_offset;
1807 __le64 sectors; /* Used device size in sectors */
1810 * Additonal Bit field of devices indicating failures to support
1811 * up to 256 devices with the 1.9.0 on-disk metadata format
1813 __le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
1815 __le32 incompat_features; /* Used to indicate any incompatible features */
1817 /* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
1821 * Check for reshape constraints on raid set @rs:
1823 * - reshape function non-existent
1825 * - ongoing recovery
1828 * Returns 0 if none or -EPERM if given constraint
1829 * and error message reference in @errmsg
1831 static int rs_check_reshape(struct raid_set *rs)
1833 struct mddev *mddev = &rs->md;
1835 if (!mddev->pers || !mddev->pers->check_reshape)
1836 rs->ti->error = "Reshape not supported";
1837 else if (mddev->degraded)
1838 rs->ti->error = "Can't reshape degraded raid set";
1839 else if (rs_is_recovering(rs))
1840 rs->ti->error = "Convert request on recovering raid set prohibited";
1841 else if (rs_is_reshaping(rs))
1842 rs->ti->error = "raid set already reshaping!";
1843 else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
1844 rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
1851 static int read_disk_sb(struct md_rdev *rdev, int size)
1853 BUG_ON(!rdev->sb_page);
1855 if (rdev->sb_loaded)
1858 if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, true)) {
1859 DMERR("Failed to read superblock of device at position %d",
1861 md_error(rdev->mddev, rdev);
1865 rdev->sb_loaded = 1;
1870 static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1872 failed_devices[0] = le64_to_cpu(sb->failed_devices);
1873 memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
1875 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
1876 int i = ARRAY_SIZE(sb->extended_failed_devices);
1879 failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
1883 static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1885 int i = ARRAY_SIZE(sb->extended_failed_devices);
1887 sb->failed_devices = cpu_to_le64(failed_devices[0]);
1889 sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
1893 * Synchronize the superblock members with the raid set properties
1895 * All superblock data is little endian.
1897 static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
1899 bool update_failed_devices = false;
1901 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
1902 struct dm_raid_superblock *sb;
1903 struct raid_set *rs = container_of(mddev, struct raid_set, md);
1905 /* No metadata device, no superblock */
1906 if (!rdev->meta_bdev)
1909 BUG_ON(!rdev->sb_page);
1911 sb = page_address(rdev->sb_page);
1913 sb_retrieve_failed_devices(sb, failed_devices);
1915 for (i = 0; i < rs->raid_disks; i++)
1916 if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
1917 update_failed_devices = true;
1918 set_bit(i, (void *) failed_devices);
1921 if (update_failed_devices)
1922 sb_update_failed_devices(sb, failed_devices);
1924 sb->magic = cpu_to_le32(DM_RAID_MAGIC);
1925 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
1927 sb->num_devices = cpu_to_le32(mddev->raid_disks);
1928 sb->array_position = cpu_to_le32(rdev->raid_disk);
1930 sb->events = cpu_to_le64(mddev->events);
1932 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
1933 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
1935 sb->level = cpu_to_le32(mddev->level);
1936 sb->layout = cpu_to_le32(mddev->layout);
1937 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
1939 sb->new_level = cpu_to_le32(mddev->new_level);
1940 sb->new_layout = cpu_to_le32(mddev->new_layout);
1941 sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
1943 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1945 smp_rmb(); /* Make sure we access most recent reshape position */
1946 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1947 if (le64_to_cpu(sb->reshape_position) != MaxSector) {
1948 /* Flag ongoing reshape */
1949 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
1951 if (mddev->delta_disks < 0 || mddev->reshape_backwards)
1952 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
1954 /* Clear reshape flags */
1955 sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
1958 sb->array_sectors = cpu_to_le64(mddev->array_sectors);
1959 sb->data_offset = cpu_to_le64(rdev->data_offset);
1960 sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
1961 sb->sectors = cpu_to_le64(rdev->sectors);
1962 sb->incompat_features = cpu_to_le32(0);
1964 /* Zero out the rest of the payload after the size of the superblock */
1965 memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
1971 * This function creates a superblock if one is not found on the device
1972 * and will decide which superblock to use if there's a choice.
1974 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
1976 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
1979 struct dm_raid_superblock *sb;
1980 struct dm_raid_superblock *refsb;
1981 uint64_t events_sb, events_refsb;
1984 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
1985 if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) {
1986 DMERR("superblock size of a logical block is no longer valid");
1990 r = read_disk_sb(rdev, rdev->sb_size);
1994 sb = page_address(rdev->sb_page);
1997 * Two cases that we want to write new superblocks and rebuild:
1998 * 1) New device (no matching magic number)
1999 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
2001 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
2002 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
2003 super_sync(rdev->mddev, rdev);
2005 set_bit(FirstUse, &rdev->flags);
2006 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2008 /* Force writing of superblocks to disk */
2009 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags);
2011 /* Any superblock is better than none, choose that if given */
2012 return refdev ? 0 : 1;
2018 events_sb = le64_to_cpu(sb->events);
2020 refsb = page_address(refdev->sb_page);
2021 events_refsb = le64_to_cpu(refsb->events);
2023 return (events_sb > events_refsb) ? 1 : 0;
2026 static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
2030 struct mddev *mddev = &rs->md;
2032 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2033 struct dm_raid_superblock *sb;
2034 uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
2036 struct dm_raid_superblock *sb2;
2038 sb = page_address(rdev->sb_page);
2039 events_sb = le64_to_cpu(sb->events);
2042 * Initialise to 1 if this is a new superblock.
2044 mddev->events = events_sb ? : 1;
2046 mddev->reshape_position = MaxSector;
2049 * Reshaping is supported, e.g. reshape_position is valid
2050 * in superblock and superblock content is authoritative.
2052 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2053 /* Superblock is authoritative wrt given raid set layout! */
2054 mddev->raid_disks = le32_to_cpu(sb->num_devices);
2055 mddev->level = le32_to_cpu(sb->level);
2056 mddev->layout = le32_to_cpu(sb->layout);
2057 mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
2058 mddev->new_level = le32_to_cpu(sb->new_level);
2059 mddev->new_layout = le32_to_cpu(sb->new_layout);
2060 mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
2061 mddev->delta_disks = le32_to_cpu(sb->delta_disks);
2062 mddev->array_sectors = le64_to_cpu(sb->array_sectors);
2064 /* raid was reshaping and got interrupted */
2065 if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2066 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2067 DMERR("Reshape requested but raid set is still reshaping");
2071 if (mddev->delta_disks < 0 ||
2072 (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2073 mddev->reshape_backwards = 1;
2075 mddev->reshape_backwards = 0;
2077 mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2078 rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
2083 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2085 if (le32_to_cpu(sb->level) != mddev->level) {
2086 DMERR("Reshaping/takeover raid sets not yet supported. (raid level/stripes/size change)");
2089 if (le32_to_cpu(sb->layout) != mddev->layout) {
2090 DMERR("Reshaping raid sets not yet supported. (raid layout change)");
2091 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout);
2092 DMERR(" Old layout: %s w/ %d copies",
2093 raid10_md_layout_to_format(le32_to_cpu(sb->layout)),
2094 raid10_md_layout_to_copies(le32_to_cpu(sb->layout)));
2095 DMERR(" New layout: %s w/ %d copies",
2096 raid10_md_layout_to_format(mddev->layout),
2097 raid10_md_layout_to_copies(mddev->layout));
2100 if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) {
2101 DMERR("Reshaping raid sets not yet supported. (stripe sectors change)");
2105 /* We can only change the number of devices in raid1 with old (i.e. pre 1.0.7) metadata */
2106 if (!rt_is_raid1(rs->raid_type) &&
2107 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) {
2108 DMERR("Reshaping raid sets not yet supported. (device count change from %u to %u)",
2109 sb->num_devices, mddev->raid_disks);
2113 /* Table line is checked vs. authoritative superblock */
2117 if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2118 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2121 * During load, we set FirstUse if a new superblock was written.
2122 * There are two reasons we might not have a superblock:
2123 * 1) The raid set is brand new - in which case, all of the
2124 * devices must have their In_sync bit set. Also,
2125 * recovery_cp must be 0, unless forced.
2126 * 2) This is a new device being added to an old raid set
2127 * and the new device needs to be rebuilt - in which
2128 * case the In_sync bit will /not/ be set and
2129 * recovery_cp must be MaxSector.
2130 * 3) This is/are a new device(s) being added to an old
2131 * raid set during takeover to a higher raid level
2132 * to provide capacity for redundancy or during reshape
2133 * to add capacity to grow the raid set.
2136 rdev_for_each(r, mddev) {
2137 if (test_bit(FirstUse, &r->flags))
2140 if (!test_bit(In_sync, &r->flags)) {
2141 DMINFO("Device %d specified for rebuild; clearing superblock",
2145 if (test_bit(FirstUse, &r->flags))
2152 if (new_devs == rs->raid_disks || !rebuilds) {
2153 /* Replace a broken device */
2154 if (new_devs == 1 && !rs->delta_disks)
2156 if (new_devs == rs->raid_disks) {
2157 DMINFO("Superblocks created for new raid set");
2158 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2159 } else if (new_devs != rebuilds &&
2160 new_devs != rs->delta_disks) {
2161 DMERR("New device injected into existing raid set without "
2162 "'delta_disks' or 'rebuild' parameter specified");
2165 } else if (new_devs && new_devs != rebuilds) {
2166 DMERR("%u 'rebuild' devices cannot be injected into"
2167 " a raid set with %u other first-time devices",
2168 rebuilds, new_devs);
2170 } else if (rebuilds) {
2171 if (rebuild_and_new && rebuilds != rebuild_and_new) {
2172 DMERR("new device%s provided without 'rebuild'",
2173 new_devs > 1 ? "s" : "");
2175 } else if (rs_is_recovering(rs)) {
2176 DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2177 (unsigned long long) mddev->recovery_cp);
2179 } else if (rs_is_reshaping(rs)) {
2180 DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2181 (unsigned long long) mddev->reshape_position);
2187 * Now we set the Faulty bit for those devices that are
2188 * recorded in the superblock as failed.
2190 sb_retrieve_failed_devices(sb, failed_devices);
2191 rdev_for_each(r, mddev) {
2194 sb2 = page_address(r->sb_page);
2195 sb2->failed_devices = 0;
2196 memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2199 * Check for any device re-ordering.
2201 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2202 role = le32_to_cpu(sb2->array_position);
2206 if (role != r->raid_disk) {
2207 if (__is_raid10_near(mddev->layout)) {
2208 if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2209 rs->raid_disks % rs->raid10_copies) {
2211 "Cannot change raid10 near set to odd # of devices!";
2215 sb2->array_position = cpu_to_le32(r->raid_disk);
2217 } else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2218 !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2219 !rt_is_raid1(rs->raid_type)) {
2220 rs->ti->error = "Cannot change device positions in raid set";
2224 DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2228 * Partial recovery is performed on
2229 * returning failed devices.
2231 if (test_bit(role, (void *) failed_devices))
2232 set_bit(Faulty, &r->flags);
2239 static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2241 struct mddev *mddev = &rs->md;
2242 struct dm_raid_superblock *sb;
2244 if (rs_is_raid0(rs) || !rdev->sb_page)
2247 sb = page_address(rdev->sb_page);
2250 * If mddev->events is not set, we know we have not yet initialized
2253 if (!mddev->events && super_init_validation(rs, rdev))
2256 if (le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2257 rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2261 if (sb->incompat_features) {
2262 rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2266 /* Enable bitmap creation for RAID levels != 0 */
2267 mddev->bitmap_info.offset = rt_is_raid0(rs->raid_type) ? 0 : to_sector(4096);
2268 rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2270 if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2271 /* Retrieve device size stored in superblock to be prepared for shrink */
2272 rdev->sectors = le64_to_cpu(sb->sectors);
2273 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2274 if (rdev->recovery_offset == MaxSector)
2275 set_bit(In_sync, &rdev->flags);
2277 * If no reshape in progress -> we're recovering single
2278 * disk(s) and have to set the device(s) to out-of-sync
2280 else if (!rs_is_reshaping(rs))
2281 clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2285 * If a device comes back, set it as not In_sync and no longer faulty.
2287 if (test_and_clear_bit(Faulty, &rdev->flags)) {
2288 rdev->recovery_offset = 0;
2289 clear_bit(In_sync, &rdev->flags);
2290 rdev->saved_raid_disk = rdev->raid_disk;
2293 /* Reshape support -> restore repective data offsets */
2294 rdev->data_offset = le64_to_cpu(sb->data_offset);
2295 rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2301 * Analyse superblocks and select the freshest.
2303 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2306 struct raid_dev *dev;
2307 struct md_rdev *rdev, *tmp, *freshest;
2308 struct mddev *mddev = &rs->md;
2311 rdev_for_each_safe(rdev, tmp, mddev) {
2313 * Skipping super_load due to CTR_FLAG_SYNC will cause
2314 * the array to undergo initialization again as
2315 * though it were new. This is the intended effect
2316 * of the "sync" directive.
2318 * When reshaping capability is added, we must ensure
2319 * that the "sync" directive is disallowed during the
2322 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2325 if (!rdev->meta_bdev)
2328 r = super_load(rdev, freshest);
2337 dev = container_of(rdev, struct raid_dev, rdev);
2339 dm_put_device(ti, dev->meta_dev);
2341 dev->meta_dev = NULL;
2342 rdev->meta_bdev = NULL;
2345 put_page(rdev->sb_page);
2347 rdev->sb_page = NULL;
2349 rdev->sb_loaded = 0;
2352 * We might be able to salvage the data device
2353 * even though the meta device has failed. For
2354 * now, we behave as though '- -' had been
2355 * set for this device in the table.
2358 dm_put_device(ti, dev->data_dev);
2360 dev->data_dev = NULL;
2363 list_del(&rdev->same_set);
2370 if (validate_raid_redundancy(rs)) {
2371 rs->ti->error = "Insufficient redundancy to activate array";
2376 * Validation of the freshest device provides the source of
2377 * validation for the remaining devices.
2379 rs->ti->error = "Unable to assemble array: Invalid superblocks";
2380 if (super_validate(rs, freshest))
2383 rdev_for_each(rdev, mddev)
2384 if ((rdev != freshest) && super_validate(rs, rdev))
2390 * Adjust data_offset and new_data_offset on all disk members of @rs
2391 * for out of place reshaping if requested by contructor
2393 * We need free space at the beginning of each raid disk for forward
2394 * and at the end for backward reshapes which userspace has to provide
2395 * via remapping/reordering of space.
2397 static int rs_adjust_data_offsets(struct raid_set *rs)
2399 sector_t data_offset = 0, new_data_offset = 0;
2400 struct md_rdev *rdev;
2402 /* Constructor did not request data offset change */
2403 if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2404 if (!rs_is_reshapable(rs))
2410 /* HM FIXME: get InSync raid_dev? */
2411 rdev = &rs->dev[0].rdev;
2413 if (rs->delta_disks < 0) {
2415 * Removing disks (reshaping backwards):
2417 * - before reshape: data is at offset 0 and free space
2418 * is at end of each component LV
2420 * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2423 new_data_offset = rs->data_offset;
2425 } else if (rs->delta_disks > 0) {
2427 * Adding disks (reshaping forwards):
2429 * - before reshape: data is at offset rs->data_offset != 0 and
2430 * free space is at begin of each component LV
2432 * - after reshape: data is at offset 0 on each component LV
2434 data_offset = rs->data_offset;
2435 new_data_offset = 0;
2439 * User space passes in 0 for data offset after having removed reshape space
2441 * - or - (data offset != 0)
2443 * Changing RAID layout or chunk size -> toggle offsets
2445 * - before reshape: data is at offset rs->data_offset 0 and
2446 * free space is at end of each component LV
2448 * data is at offset rs->data_offset != 0 and
2449 * free space is at begin of each component LV
2451 * - after reshape: data is at offset 0 if it was at offset != 0
2452 * or at offset != 0 if it was at offset 0
2453 * on each component LV
2456 data_offset = rs->data_offset ? rdev->data_offset : 0;
2457 new_data_offset = data_offset ? 0 : rs->data_offset;
2458 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2462 * Make sure we got a minimum amount of free sectors per device
2464 if (rs->data_offset &&
2465 to_sector(i_size_read(rdev->bdev->bd_inode)) - rdev->sectors < MIN_FREE_RESHAPE_SPACE) {
2466 rs->ti->error = data_offset ? "No space for forward reshape" :
2467 "No space for backward reshape";
2471 /* Adjust data offsets on all rdevs */
2472 rdev_for_each(rdev, &rs->md) {
2473 rdev->data_offset = data_offset;
2474 rdev->new_data_offset = new_data_offset;
2480 /* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2481 static void __reorder_raid_disk_indexes(struct raid_set *rs)
2484 struct md_rdev *rdev;
2486 rdev_for_each(rdev, &rs->md) {
2487 rdev->raid_disk = i++;
2488 rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2493 * Setup @rs for takeover by a different raid level
2495 static int rs_setup_takeover(struct raid_set *rs)
2497 struct mddev *mddev = &rs->md;
2498 struct md_rdev *rdev;
2499 unsigned int d = mddev->raid_disks = rs->raid_disks;
2500 sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2502 if (rt_is_raid10(rs->raid_type)) {
2503 if (mddev->level == 0) {
2504 /* Userpace reordered disks -> adjust raid_disk indexes */
2505 __reorder_raid_disk_indexes(rs);
2507 /* raid0 -> raid10_far layout */
2508 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2510 } else if (mddev->level == 1)
2511 /* raid1 -> raid10_near layout */
2512 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2519 clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2520 mddev->recovery_cp = MaxSector;
2523 rdev = &rs->dev[d].rdev;
2525 if (test_bit(d, (void *) rs->rebuild_disks)) {
2526 clear_bit(In_sync, &rdev->flags);
2527 clear_bit(Faulty, &rdev->flags);
2528 mddev->recovery_cp = rdev->recovery_offset = 0;
2529 /* Bitmap has to be created when we do an "up" takeover */
2530 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2533 rdev->new_data_offset = new_data_offset;
2539 /* Prepare @rs for reshape */
2540 static int rs_prepare_reshape(struct raid_set *rs)
2543 struct mddev *mddev = &rs->md;
2545 if (rs_is_raid10(rs)) {
2546 if (rs->raid_disks != mddev->raid_disks &&
2547 __is_raid10_near(mddev->layout) &&
2548 rs->raid10_copies &&
2549 rs->raid10_copies != __raid10_near_copies(mddev->layout)) {
2551 * raid disk have to be multiple of data copies to allow this conversion,
2553 * This is actually not a reshape it is a
2554 * rebuild of any additional mirrors per group
2556 if (rs->raid_disks % rs->raid10_copies) {
2557 rs->ti->error = "Can't reshape raid10 mirror groups";
2561 /* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2562 __reorder_raid_disk_indexes(rs);
2563 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2565 mddev->new_layout = mddev->layout;
2570 } else if (rs_is_raid456(rs))
2573 else if (rs_is_raid1(rs)) {
2574 if (rs->delta_disks) {
2575 /* Process raid1 via delta_disks */
2576 mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
2579 /* Process raid1 without delta_disks */
2580 mddev->raid_disks = rs->raid_disks;
2584 rs->ti->error = "Called with bogus raid type";
2589 set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2590 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2591 } else if (mddev->raid_disks < rs->raid_disks)
2592 /* Create new superblocks and bitmaps, if any new disks */
2593 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2600 * - change raid layout
2601 * - change chunk size
2605 static int rs_setup_reshape(struct raid_set *rs)
2608 unsigned int cur_raid_devs, d;
2609 struct mddev *mddev = &rs->md;
2610 struct md_rdev *rdev;
2612 mddev->delta_disks = rs->delta_disks;
2613 cur_raid_devs = mddev->raid_disks;
2615 /* Ignore impossible layout change whilst adding/removing disks */
2616 if (mddev->delta_disks &&
2617 mddev->layout != mddev->new_layout) {
2618 DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2619 mddev->new_layout = mddev->layout;
2623 * Adjust array size:
2625 * - in case of adding disks, array size has
2626 * to grow after the disk adding reshape,
2627 * which'll hapen in the event handler;
2628 * reshape will happen forward, so space has to
2629 * be available at the beginning of each disk
2631 * - in case of removing disks, array size
2632 * has to shrink before starting the reshape,
2633 * which'll happen here;
2634 * reshape will happen backward, so space has to
2635 * be available at the end of each disk
2637 * - data_offset and new_data_offset are
2638 * adjusted for aforementioned out of place
2639 * reshaping based on userspace passing in
2640 * the "data_offset <sectors>" key/value
2641 * pair via the constructor
2645 if (rs->delta_disks > 0) {
2646 /* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2647 for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2648 rdev = &rs->dev[d].rdev;
2649 clear_bit(In_sync, &rdev->flags);
2652 * save_raid_disk needs to be -1, or recovery_offset will be set to 0
2653 * by md, which'll store that erroneously in the superblock on reshape
2655 rdev->saved_raid_disk = -1;
2656 rdev->raid_disk = d;
2658 rdev->sectors = mddev->dev_sectors;
2659 rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
2662 mddev->reshape_backwards = 0; /* adding disks -> forward reshape */
2664 /* Remove disk(s) */
2665 } else if (rs->delta_disks < 0) {
2666 r = rs_set_dev_and_array_sectors(rs, true);
2667 mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2669 /* Change layout and/or chunk size */
2672 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2674 * keeping number of disks and do layout change ->
2676 * toggle reshape_backward depending on data_offset:
2678 * - free space upfront -> reshape forward
2680 * - free space at the end -> reshape backward
2683 * This utilizes free reshape space avoiding the need
2684 * for userspace to move (parts of) LV segments in
2685 * case of layout/chunksize change (for disk
2686 * adding/removing reshape space has to be at
2687 * the proper address (see above with delta_disks):
2689 * add disk(s) -> begin
2690 * remove disk(s)-> end
2692 mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2699 * Enable/disable discard support on RAID set depending on
2700 * RAID level and discard properties of underlying RAID members.
2702 static void configure_discard_support(struct raid_set *rs)
2706 struct dm_target *ti = rs->ti;
2708 /* Assume discards not supported until after checks below. */
2709 ti->discards_supported = false;
2711 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */
2712 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6);
2714 for (i = 0; i < rs->raid_disks; i++) {
2715 struct request_queue *q;
2717 if (!rs->dev[i].rdev.bdev)
2720 q = bdev_get_queue(rs->dev[i].rdev.bdev);
2721 if (!q || !blk_queue_discard(q))
2725 if (!q->limits.discard_zeroes_data)
2727 if (!devices_handle_discard_safely) {
2728 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2729 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2735 /* All RAID members properly support discards */
2736 ti->discards_supported = true;
2739 * RAID1 and RAID10 personalities require bio splitting,
2740 * RAID0/4/5/6 don't and process large discard bios properly.
2742 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10);
2743 ti->num_discard_bios = 1;
2747 * Construct a RAID0/1/10/4/5/6 mapping:
2749 * <raid_type> <#raid_params> <raid_params>{0,} \
2750 * <#raid_devs> [<meta_dev1> <dev1>]{1,}
2752 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for
2753 * details on possible <raid_params>.
2755 * Userspace is free to initialize the metadata devices, hence the superblocks to
2756 * enforce recreation based on the passed in table parameters.
2759 static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
2763 struct raid_type *rt;
2764 unsigned int num_raid_params, num_raid_devs;
2765 sector_t calculated_dev_sectors;
2766 struct raid_set *rs = NULL;
2768 struct rs_layout rs_layout;
2769 struct dm_arg_set as = { argc, argv }, as_nrd;
2770 struct dm_arg _args[] = {
2771 { 0, as.argc, "Cannot understand number of raid parameters" },
2772 { 1, 254, "Cannot understand number of raid devices parameters" }
2775 /* Must have <raid_type> */
2776 arg = dm_shift_arg(&as);
2778 ti->error = "No arguments";
2782 rt = get_raid_type(arg);
2784 ti->error = "Unrecognised raid_type";
2788 /* Must have <#raid_params> */
2789 if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
2792 /* number of raid device tupples <meta_dev data_dev> */
2794 dm_consume_args(&as_nrd, num_raid_params);
2795 _args[1].max = (as_nrd.argc - 1) / 2;
2796 if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
2799 if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
2800 ti->error = "Invalid number of supplied raid devices";
2804 rs = raid_set_alloc(ti, rt, num_raid_devs);
2808 r = parse_raid_params(rs, &as, num_raid_params);
2812 r = parse_dev_params(rs, &as);
2816 rs->md.sync_super = super_sync;
2819 * Calculate ctr requested array and device sizes to allow
2820 * for superblock analysis needing device sizes defined.
2822 * Any existing superblock will overwrite the array and device sizes
2824 r = rs_set_dev_and_array_sectors(rs, false);
2828 calculated_dev_sectors = rs->dev[0].rdev.sectors;
2831 * Backup any new raid set level, layout, ...
2832 * requested to be able to compare to superblock
2833 * members for conversion decisions.
2835 rs_config_backup(rs, &rs_layout);
2837 r = analyse_superblocks(ti, rs);
2841 resize = calculated_dev_sectors != rs->dev[0].rdev.sectors;
2843 INIT_WORK(&rs->md.event_work, do_table_event);
2845 ti->num_flush_bios = 1;
2847 /* Restore any requested new layout for conversion decision */
2848 rs_config_restore(rs, &rs_layout);
2851 * Now that we have any superblock metadata available,
2852 * check for new, recovering, reshaping, to be taken over,
2853 * to be reshaped or an existing, unchanged raid set to
2856 if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
2857 /* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
2858 if (rs_is_raid6(rs) &&
2859 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
2860 ti->error = "'nosync' not allowed for new raid6 set";
2864 rs_setup_recovery(rs, 0);
2865 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2867 } else if (rs_is_recovering(rs)) {
2868 /* A recovering raid set may be resized */
2869 ; /* skip setup rs */
2870 } else if (rs_is_reshaping(rs)) {
2871 /* Have to reject size change request during reshape */
2873 ti->error = "Can't resize a reshaping raid set";
2878 } else if (rs_takeover_requested(rs)) {
2879 if (rs_is_reshaping(rs)) {
2880 ti->error = "Can't takeover a reshaping raid set";
2886 * If a takeover is needed, userspace sets any additional
2887 * devices to rebuild and we can check for a valid request here.
2889 * If acceptible, set the level to the new requested
2890 * one, prohibit requesting recovery, allow the raid
2891 * set to run and store superblocks during resume.
2893 r = rs_check_takeover(rs);
2897 r = rs_setup_takeover(rs);
2901 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2902 /* Takeover ain't recovery, so disable recovery */
2903 rs_setup_recovery(rs, MaxSector);
2905 } else if (rs_reshape_requested(rs)) {
2907 * We can only prepare for a reshape here, because the
2908 * raid set needs to run to provide the repective reshape
2909 * check functions via its MD personality instance.
2911 * So do the reshape check after md_run() succeeded.
2913 r = rs_prepare_reshape(rs);
2917 /* Reshaping ain't recovery, so disable recovery */
2918 rs_setup_recovery(rs, MaxSector);
2921 /* May not set recovery when a device rebuild is requested */
2922 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
2923 rs_setup_recovery(rs, MaxSector);
2924 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2926 rs_setup_recovery(rs, test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ?
2927 0 : (resize ? calculated_dev_sectors : MaxSector));
2931 /* If constructor requested it, change data and new_data offsets */
2932 r = rs_adjust_data_offsets(rs);
2936 /* Start raid set read-only and assumed clean to change in raid_resume() */
2939 set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
2941 /* Has to be held on running the array */
2942 mddev_lock_nointr(&rs->md);
2943 r = md_run(&rs->md);
2944 rs->md.in_sync = 0; /* Assume already marked dirty */
2947 ti->error = "Failed to run raid array";
2948 mddev_unlock(&rs->md);
2952 rs->callbacks.congested_fn = raid_is_congested;
2953 dm_table_add_target_callbacks(ti->table, &rs->callbacks);
2955 mddev_suspend(&rs->md);
2957 /* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
2958 if (rs_is_raid456(rs)) {
2959 r = rs_set_raid456_stripe_cache(rs);
2961 goto bad_stripe_cache;
2964 /* Now do an early reshape check */
2965 if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
2966 r = rs_check_reshape(rs);
2968 goto bad_check_reshape;
2970 /* Restore new, ctr requested layout to perform check */
2971 rs_config_restore(rs, &rs_layout);
2973 if (rs->md.pers->start_reshape) {
2974 r = rs->md.pers->check_reshape(&rs->md);
2976 ti->error = "Reshape check failed";
2977 goto bad_check_reshape;
2982 mddev_unlock(&rs->md);
2994 static void raid_dtr(struct dm_target *ti)
2996 struct raid_set *rs = ti->private;
2998 list_del_init(&rs->callbacks.list);
3003 static int raid_map(struct dm_target *ti, struct bio *bio)
3005 struct raid_set *rs = ti->private;
3006 struct mddev *mddev = &rs->md;
3009 * If we're reshaping to add disk(s)), ti->len and
3010 * mddev->array_sectors will differ during the process
3011 * (ti->len > mddev->array_sectors), so we have to requeue
3012 * bios with addresses > mddev->array_sectors here or
3013 * there will occur accesses past EOD of the component
3014 * data images thus erroring the raid set.
3016 if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
3017 return DM_MAPIO_REQUEUE;
3019 mddev->pers->make_request(mddev, bio);
3021 return DM_MAPIO_SUBMITTED;
3024 /* Return string describing the current sync action of @mddev */
3025 static const char *decipher_sync_action(struct mddev *mddev)
3027 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
3030 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3031 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
3032 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
3035 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
3036 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
3038 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
3043 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
3051 * Return status string @rdev
3053 * Status characters:
3055 * 'D' = Dead/Failed device
3056 * 'a' = Alive but not in-sync
3057 * 'A' = Alive and in-sync
3059 static const char *__raid_dev_status(struct md_rdev *rdev, bool array_in_sync)
3061 if (test_bit(Faulty, &rdev->flags))
3063 else if (!array_in_sync || !test_bit(In_sync, &rdev->flags))
3069 /* Helper to return resync/reshape progress for @rs and @array_in_sync */
3070 static sector_t rs_get_progress(struct raid_set *rs,
3071 sector_t resync_max_sectors, bool *array_in_sync)
3073 sector_t r, recovery_cp, curr_resync_completed;
3074 struct mddev *mddev = &rs->md;
3076 curr_resync_completed = mddev->curr_resync_completed ?: mddev->recovery_cp;
3077 recovery_cp = mddev->recovery_cp;
3078 *array_in_sync = false;
3080 if (rs_is_raid0(rs)) {
3081 r = resync_max_sectors;
3082 *array_in_sync = true;
3085 r = mddev->reshape_position;
3087 /* Reshape is relative to the array size */
3088 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ||
3090 if (r == MaxSector) {
3091 *array_in_sync = true;
3092 r = resync_max_sectors;
3094 /* Got to reverse on backward reshape */
3095 if (mddev->reshape_backwards)
3096 r = mddev->array_sectors - r;
3098 /* Devide by # of data stripes */
3099 sector_div(r, mddev_data_stripes(rs));
3102 /* Sync is relative to the component device size */
3103 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3104 r = curr_resync_completed;
3108 if (r == MaxSector) {
3112 *array_in_sync = true;
3113 r = resync_max_sectors;
3114 } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
3116 * If "check" or "repair" is occurring, the raid set has
3117 * undergone an initial sync and the health characters
3118 * should not be 'a' anymore.
3120 *array_in_sync = true;
3122 struct md_rdev *rdev;
3125 * The raid set may be doing an initial sync, or it may
3126 * be rebuilding individual components. If all the
3127 * devices are In_sync, then it is the raid set that is
3128 * being initialized.
3130 rdev_for_each(rdev, mddev)
3131 if (!test_bit(In_sync, &rdev->flags))
3132 *array_in_sync = true;
3134 r = 0; /* HM FIXME: TESTME: https://bugzilla.redhat.com/show_bug.cgi?id=1210637 ? */
3142 /* Helper to return @dev name or "-" if !@dev */
3143 static const char *__get_dev_name(struct dm_dev *dev)
3145 return dev ? dev->name : "-";
3148 static void raid_status(struct dm_target *ti, status_type_t type,
3149 unsigned int status_flags, char *result, unsigned int maxlen)
3151 struct raid_set *rs = ti->private;
3152 struct mddev *mddev = &rs->md;
3153 struct r5conf *conf = mddev->private;
3154 int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3156 unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3157 unsigned int sz = 0;
3158 unsigned int rebuild_disks;
3159 unsigned int write_mostly_params = 0;
3160 sector_t progress, resync_max_sectors, resync_mismatches;
3161 const char *sync_action;
3162 struct raid_type *rt;
3163 struct md_rdev *rdev;
3166 case STATUSTYPE_INFO:
3167 /* *Should* always succeed */
3168 rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3172 DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3174 /* Access most recent mddev properties for status output */
3176 /* Get sensible max sectors even if raid set not yet started */
3177 resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3178 mddev->resync_max_sectors : mddev->dev_sectors;
3179 progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync);
3180 resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
3181 atomic64_read(&mddev->resync_mismatches) : 0;
3182 sync_action = decipher_sync_action(&rs->md);
3184 /* HM FIXME: do we want another state char for raid0? It shows 'D' or 'A' now */
3185 rdev_for_each(rdev, mddev)
3186 DMEMIT(__raid_dev_status(rdev, array_in_sync));
3189 * In-sync/Reshape ratio:
3190 * The in-sync ratio shows the progress of:
3191 * - Initializing the raid set
3192 * - Rebuilding a subset of devices of the raid set
3193 * The user can distinguish between the two by referring
3194 * to the status characters.
3196 * The reshape ratio shows the progress of
3197 * changing the raid layout or the number of
3198 * disks of a raid set
3200 DMEMIT(" %llu/%llu", (unsigned long long) progress,
3201 (unsigned long long) resync_max_sectors);
3207 * See Documentation/device-mapper/dm-raid.txt for
3208 * information on each of these states.
3210 DMEMIT(" %s", sync_action);
3215 * resync_mismatches/mismatch_cnt
3216 * This field shows the number of discrepancies found when
3217 * performing a "check" of the raid set.
3219 DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3224 * data_offset (needed for out of space reshaping)
3225 * This field shows the data offset into the data
3226 * image LV where the first stripes data starts.
3228 * We keep data_offset equal on all raid disks of the set,
3229 * so retrieving it from the first raid disk is sufficient.
3231 DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
3234 case STATUSTYPE_TABLE:
3235 /* Report the table line string you would use to construct this raid set */
3237 /* Calculate raid parameter count */
3238 for (i = 0; i < rs->raid_disks; i++)
3239 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3240 write_mostly_params += 2;
3241 rebuild_disks = memweight(rs->rebuild_disks, DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks));
3242 raid_param_cnt += rebuild_disks * 2 +
3243 write_mostly_params +
3244 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3245 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
3246 /* Emit table line */
3247 DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3248 if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3249 DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3250 raid10_md_layout_to_format(mddev->layout));
3251 if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3252 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3253 raid10_md_layout_to_copies(mddev->layout));
3254 if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3255 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3256 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3257 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
3258 if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3259 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3260 (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3261 if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3262 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3263 (unsigned long long) rs->data_offset);
3264 if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3265 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3266 mddev->bitmap_info.daemon_sleep);
3267 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3268 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3269 max(rs->delta_disks, mddev->delta_disks));
3270 if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3271 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3274 for (i = 0; i < rs->raid_disks; i++)
3275 if (test_bit(rs->dev[i].rdev.raid_disk, (void *) rs->rebuild_disks))
3276 DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD),
3277 rs->dev[i].rdev.raid_disk);
3278 if (write_mostly_params)
3279 for (i = 0; i < rs->raid_disks; i++)
3280 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3281 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3282 rs->dev[i].rdev.raid_disk);
3283 if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3284 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3285 mddev->bitmap_info.max_write_behind);
3286 if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3287 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3288 mddev->sync_speed_max);
3289 if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3290 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3291 mddev->sync_speed_min);
3292 DMEMIT(" %d", rs->raid_disks);
3293 for (i = 0; i < rs->raid_disks; i++)
3294 DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
3295 __get_dev_name(rs->dev[i].data_dev));
3299 static int raid_message(struct dm_target *ti, unsigned int argc, char **argv)
3301 struct raid_set *rs = ti->private;
3302 struct mddev *mddev = &rs->md;
3304 if (!mddev->pers || !mddev->pers->sync_request)
3307 if (!strcasecmp(argv[0], "frozen"))
3308 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3310 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3312 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
3313 if (mddev->sync_thread) {
3314 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3315 md_reap_sync_thread(mddev);
3317 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3318 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
3320 else if (!strcasecmp(argv[0], "resync"))
3321 ; /* MD_RECOVERY_NEEDED set below */
3322 else if (!strcasecmp(argv[0], "recover"))
3323 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3325 if (!strcasecmp(argv[0], "check"))
3326 set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3327 else if (!!strcasecmp(argv[0], "repair"))
3329 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3330 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3332 if (mddev->ro == 2) {
3333 /* A write to sync_action is enough to justify
3334 * canceling read-auto mode
3337 if (!mddev->suspended && mddev->sync_thread)
3338 md_wakeup_thread(mddev->sync_thread);
3340 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3341 if (!mddev->suspended && mddev->thread)
3342 md_wakeup_thread(mddev->thread);
3347 static int raid_iterate_devices(struct dm_target *ti,
3348 iterate_devices_callout_fn fn, void *data)
3350 struct raid_set *rs = ti->private;
3354 for (i = 0; !r && i < rs->md.raid_disks; i++)
3355 if (rs->dev[i].data_dev)
3357 rs->dev[i].data_dev,
3358 0, /* No offset on data devs */
3365 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3367 struct raid_set *rs = ti->private;
3368 unsigned int chunk_size = to_bytes(rs->md.chunk_sectors);
3370 blk_limits_io_min(limits, chunk_size);
3371 blk_limits_io_opt(limits, chunk_size * mddev_data_stripes(rs));
3374 static void raid_presuspend(struct dm_target *ti)
3376 struct raid_set *rs = ti->private;
3378 md_stop_writes(&rs->md);
3381 static void raid_postsuspend(struct dm_target *ti)
3383 struct raid_set *rs = ti->private;
3385 if (test_and_clear_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
3386 if (!rs->md.suspended)
3387 mddev_suspend(&rs->md);
3392 static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3395 uint64_t failed_devices, cleared_failed_devices = 0;
3396 unsigned long flags;
3397 struct dm_raid_superblock *sb;
3400 for (i = 0; i < rs->md.raid_disks; i++) {
3401 r = &rs->dev[i].rdev;
3402 if (test_bit(Faulty, &r->flags) && r->sb_page &&
3403 sync_page_io(r, 0, r->sb_size, r->sb_page,
3404 REQ_OP_READ, 0, true)) {
3405 DMINFO("Faulty %s device #%d has readable super block."
3406 " Attempting to revive it.",
3407 rs->raid_type->name, i);
3410 * Faulty bit may be set, but sometimes the array can
3411 * be suspended before the personalities can respond
3412 * by removing the device from the array (i.e. calling
3413 * 'hot_remove_disk'). If they haven't yet removed
3414 * the failed device, its 'raid_disk' number will be
3415 * '>= 0' - meaning we must call this function
3418 if ((r->raid_disk >= 0) &&
3419 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0))
3420 /* Failed to revive this device, try next */
3424 r->saved_raid_disk = i;
3426 clear_bit(Faulty, &r->flags);
3427 clear_bit(WriteErrorSeen, &r->flags);
3428 clear_bit(In_sync, &r->flags);
3429 if (r->mddev->pers->hot_add_disk(r->mddev, r)) {
3431 r->saved_raid_disk = -1;
3434 r->recovery_offset = 0;
3435 cleared_failed_devices |= 1 << i;
3439 if (cleared_failed_devices) {
3440 rdev_for_each(r, &rs->md) {
3441 sb = page_address(r->sb_page);
3442 failed_devices = le64_to_cpu(sb->failed_devices);
3443 failed_devices &= ~cleared_failed_devices;
3444 sb->failed_devices = cpu_to_le64(failed_devices);
3449 static int __load_dirty_region_bitmap(struct raid_set *rs)
3453 /* Try loading the bitmap unless "raid0", which does not have one */
3454 if (!rs_is_raid0(rs) &&
3455 !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
3456 r = bitmap_load(&rs->md);
3458 DMERR("Failed to load bitmap");
3464 /* Enforce updating all superblocks */
3465 static void rs_update_sbs(struct raid_set *rs)
3467 struct mddev *mddev = &rs->md;
3470 set_bit(MD_CHANGE_DEVS, &mddev->flags);
3472 md_update_sb(mddev, 1);
3477 * Reshape changes raid algorithm of @rs to new one within personality
3478 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3479 * disks from a raid set thus growing/shrinking it or resizes the set
3481 * Call mddev_lock_nointr() before!
3483 static int rs_start_reshape(struct raid_set *rs)
3486 struct mddev *mddev = &rs->md;
3487 struct md_personality *pers = mddev->pers;
3489 r = rs_setup_reshape(rs);
3493 /* Need to be resumed to be able to start reshape, recovery is frozen until raid_resume() though */
3494 if (mddev->suspended)
3495 mddev_resume(mddev);
3498 * Check any reshape constraints enforced by the personalility
3500 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3502 r = pers->check_reshape(mddev);
3504 rs->ti->error = "pers->check_reshape() failed";
3509 * Personality may not provide start reshape method in which
3510 * case check_reshape above has already covered everything
3512 if (pers->start_reshape) {
3513 r = pers->start_reshape(mddev);
3515 rs->ti->error = "pers->start_reshape() failed";
3520 /* Suspend because a resume will happen in raid_resume() */
3521 if (!mddev->suspended)
3522 mddev_suspend(mddev);
3525 * Now reshape got set up, update superblocks to
3526 * reflect the fact so that a table reload will
3527 * access proper superblock content in the ctr.
3534 static int raid_preresume(struct dm_target *ti)
3537 struct raid_set *rs = ti->private;
3538 struct mddev *mddev = &rs->md;
3540 /* This is a resume after a suspend of the set -> it's already started */
3541 if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
3545 * The superblocks need to be updated on disk if the
3546 * array is new or new devices got added (thus zeroed
3547 * out by userspace) or __load_dirty_region_bitmap
3548 * will overwrite them in core with old data or fail.
3550 if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
3554 * Disable/enable discard support on raid set after any
3555 * conversion, because devices can have been added
3557 configure_discard_support(rs);
3559 /* Load the bitmap from disk unless raid0 */
3560 r = __load_dirty_region_bitmap(rs);
3564 /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */
3565 if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) &&
3566 mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) {
3567 r = bitmap_resize(mddev->bitmap, mddev->dev_sectors,
3568 to_bytes(rs->requested_bitmap_chunk_sectors), 0);
3570 DMERR("Failed to resize bitmap");
3573 /* Check for any resize/reshape on @rs and adjust/initiate */
3574 /* Be prepared for mddev_resume() in raid_resume() */
3575 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3576 if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
3577 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3578 mddev->resync_min = mddev->recovery_cp;
3581 rs_set_capacity(rs);
3583 /* Check for any reshape request unless new raid set */
3584 if (test_and_clear_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3585 /* Initiate a reshape. */
3586 mddev_lock_nointr(mddev);
3587 r = rs_start_reshape(rs);
3588 mddev_unlock(mddev);
3590 DMWARN("Failed to check/start reshape, continuing without change");
3597 static void raid_resume(struct dm_target *ti)
3599 struct raid_set *rs = ti->private;
3600 struct mddev *mddev = &rs->md;
3602 if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
3604 * A secondary resume while the device is active.
3605 * Take this opportunity to check whether any failed
3606 * devices are reachable again.
3608 attempt_restore_of_faulty_devices(rs);
3614 * When passing in flags to the ctr, we expect userspace
3615 * to reset them because they made it to the superblocks
3616 * and reload the mapping anyway.
3618 * -> only unfreeze recovery in case of a table reload or
3619 * we'll have a bogus recovery/reshape position
3620 * retrieved from the superblock by the ctr because
3621 * the ongoing recovery/reshape will change it after read.
3623 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3625 if (mddev->suspended)
3626 mddev_resume(mddev);
3630 static struct target_type raid_target = {
3632 .version = {1, 9, 0},
3633 .module = THIS_MODULE,
3637 .status = raid_status,
3638 .message = raid_message,
3639 .iterate_devices = raid_iterate_devices,
3640 .io_hints = raid_io_hints,
3641 .presuspend = raid_presuspend,
3642 .postsuspend = raid_postsuspend,
3643 .preresume = raid_preresume,
3644 .resume = raid_resume,
3647 static int __init dm_raid_init(void)
3649 DMINFO("Loading target version %u.%u.%u",
3650 raid_target.version[0],
3651 raid_target.version[1],
3652 raid_target.version[2]);
3653 return dm_register_target(&raid_target);
3656 static void __exit dm_raid_exit(void)
3658 dm_unregister_target(&raid_target);
3661 module_init(dm_raid_init);
3662 module_exit(dm_raid_exit);
3664 module_param(devices_handle_discard_safely, bool, 0644);
3665 MODULE_PARM_DESC(devices_handle_discard_safely,
3666 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
3668 MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
3669 MODULE_ALIAS("dm-raid0");
3670 MODULE_ALIAS("dm-raid1");
3671 MODULE_ALIAS("dm-raid10");
3672 MODULE_ALIAS("dm-raid4");
3673 MODULE_ALIAS("dm-raid5");
3674 MODULE_ALIAS("dm-raid6");
3675 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
3676 MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
3677 MODULE_LICENSE("GPL");