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 raid4/5/6/10! */
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_DATA_OFFSET)
137 /* "raid10" does not accept any raid1 or stripe cache options */
138 #define RAID10_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
140 CTR_FLAG_DAEMON_SLEEP | \
141 CTR_FLAG_MIN_RECOVERY_RATE | \
142 CTR_FLAG_MAX_RECOVERY_RATE | \
143 CTR_FLAG_REGION_SIZE | \
144 CTR_FLAG_RAID10_COPIES | \
145 CTR_FLAG_RAID10_FORMAT | \
146 CTR_FLAG_DELTA_DISKS | \
147 CTR_FLAG_DATA_OFFSET | \
148 CTR_FLAG_RAID10_USE_NEAR_SETS)
151 * "raid4/5/6" do not accept any raid1 or raid10 specific options
153 * "raid6" does not accept "nosync", because it is not guaranteed
154 * that both parity and q-syndrome are being written properly with
157 #define RAID45_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
159 CTR_FLAG_DAEMON_SLEEP | \
160 CTR_FLAG_MIN_RECOVERY_RATE | \
161 CTR_FLAG_MAX_RECOVERY_RATE | \
162 CTR_FLAG_MAX_WRITE_BEHIND | \
163 CTR_FLAG_STRIPE_CACHE | \
164 CTR_FLAG_REGION_SIZE | \
165 CTR_FLAG_DELTA_DISKS | \
166 CTR_FLAG_DATA_OFFSET)
168 #define RAID6_VALID_FLAGS (CTR_FLAG_SYNC | \
170 CTR_FLAG_DAEMON_SLEEP | \
171 CTR_FLAG_MIN_RECOVERY_RATE | \
172 CTR_FLAG_MAX_RECOVERY_RATE | \
173 CTR_FLAG_MAX_WRITE_BEHIND | \
174 CTR_FLAG_STRIPE_CACHE | \
175 CTR_FLAG_REGION_SIZE | \
176 CTR_FLAG_DELTA_DISKS | \
177 CTR_FLAG_DATA_OFFSET)
178 /* ...valid options definitions per raid level */
181 * Flags for rs->runtime_flags field
182 * (RT_FLAG prefix meaning "runtime flag")
184 * These are all internal and used to define runtime state,
185 * e.g. to prevent another resume from preresume processing
186 * the raid set all over again.
188 #define RT_FLAG_RS_PRERESUMED 0
189 #define RT_FLAG_RS_RESUMED 1
190 #define RT_FLAG_RS_BITMAP_LOADED 2
191 #define RT_FLAG_UPDATE_SBS 3
192 #define RT_FLAG_RESHAPE_RS 4
193 #define RT_FLAG_KEEP_RS_FROZEN 5
195 /* Array elements of 64 bit needed for rebuild/write_mostly 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 parity_devs; /* # of parity devices. */
259 const unsigned minimal_devs; /* minimal # of devices in set. */
260 const unsigned level; /* RAID level. */
261 const unsigned 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, "writemostly"},
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 * is. 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 4, 5 or 6 */
353 static bool rs_is_raid456(struct raid_set *rs)
355 return __within_range(rs->md.level, 4, 6);
358 /* Return true, if raid set in @rs is reshapable */
359 static unsigned int __is_raid10_far(int layout);
360 static bool rs_is_reshapable(struct raid_set *rs)
362 return rs_is_raid456(rs) ||
363 (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
366 /* Return true, if raid set in @rs is recovering */
367 static bool rs_is_recovering(struct raid_set *rs)
369 return rs->md.recovery_cp != MaxSector;
372 /* Return true, if raid set in @rs is reshaping */
373 static bool rs_is_reshaping(struct raid_set *rs)
375 return rs->md.reshape_position != MaxSector;
379 * bool helpers to test for various raid levels of a raid type
382 /* Return true, if raid type in @rt is raid0 */
383 static bool rt_is_raid0(struct raid_type *rt)
388 /* Return true, if raid type in @rt is raid1 */
389 static bool rt_is_raid1(struct raid_type *rt)
391 return rt->level == 1;
394 /* Return true, if raid type in @rt is raid10 */
395 static bool rt_is_raid10(struct raid_type *rt)
397 return rt->level == 10;
400 /* Return true, if raid type in @rt is raid4/5 */
401 static bool rt_is_raid45(struct raid_type *rt)
403 return __within_range(rt->level, 4, 5);
406 /* Return true, if raid type in @rt is raid6 */
407 static bool rt_is_raid6(struct raid_type *rt)
409 return rt->level == 6;
412 /* Return true, if raid type in @rt is raid4/5/6 */
413 static bool rt_is_raid456(struct raid_type *rt)
415 return __within_range(rt->level, 4, 6);
417 /* END: raid level bools */
419 /* Return valid ctr flags for the raid level of @rs */
420 static unsigned long __valid_flags(struct raid_set *rs)
422 if (rt_is_raid0(rs->raid_type))
423 return RAID0_VALID_FLAGS;
424 else if (rt_is_raid1(rs->raid_type))
425 return RAID1_VALID_FLAGS;
426 else if (rt_is_raid10(rs->raid_type))
427 return RAID10_VALID_FLAGS;
428 else if (rt_is_raid45(rs->raid_type))
429 return RAID45_VALID_FLAGS;
430 else if (rt_is_raid6(rs->raid_type))
431 return RAID6_VALID_FLAGS;
437 * Check for valid flags set on @rs
439 * Has to be called after parsing of the ctr flags!
441 static int rs_check_for_valid_flags(struct raid_set *rs)
443 if (rs->ctr_flags & ~__valid_flags(rs)) {
444 rs->ti->error = "Invalid flags combination";
451 /* MD raid10 bit definitions and helpers */
452 #define RAID10_OFFSET (1 << 16) /* stripes with data copies area adjacent on devices */
453 #define RAID10_BROCKEN_USE_FAR_SETS (1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
454 #define RAID10_USE_FAR_SETS (1 << 18) /* Use sets instead of whole stripe rotation */
455 #define RAID10_FAR_COPIES_SHIFT 8 /* raid10 # far copies shift (2nd byte of layout) */
457 /* Return md raid10 near copies for @layout */
458 static unsigned int __raid10_near_copies(int layout)
460 return layout & 0xFF;
463 /* Return md raid10 far copies for @layout */
464 static unsigned int __raid10_far_copies(int layout)
466 return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
469 /* Return true if md raid10 offset for @layout */
470 static unsigned int __is_raid10_offset(int layout)
472 return layout & RAID10_OFFSET;
475 /* Return true if md raid10 near for @layout */
476 static unsigned int __is_raid10_near(int layout)
478 return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
481 /* Return true if md raid10 far for @layout */
482 static unsigned int __is_raid10_far(int layout)
484 return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
487 /* Return md raid10 layout string for @layout */
488 static const char *raid10_md_layout_to_format(int layout)
491 * Bit 16 stands for "offset"
492 * (i.e. adjacent stripes hold copies)
494 * Refer to MD's raid10.c for details
496 if (__is_raid10_offset(layout))
499 if (__raid10_near_copies(layout) > 1)
502 WARN_ON(__raid10_far_copies(layout) < 2);
507 /* Return md raid10 algorithm for @name */
508 static int raid10_name_to_format(const char *name)
510 if (!strcasecmp(name, "near"))
511 return ALGORITHM_RAID10_NEAR;
512 else if (!strcasecmp(name, "offset"))
513 return ALGORITHM_RAID10_OFFSET;
514 else if (!strcasecmp(name, "far"))
515 return ALGORITHM_RAID10_FAR;
520 /* Return md raid10 copies for @layout */
521 static unsigned int raid10_md_layout_to_copies(int layout)
523 return __raid10_near_copies(layout) > 1 ?
524 __raid10_near_copies(layout) : __raid10_far_copies(layout);
527 /* Return md raid10 format id for @format string */
528 static int raid10_format_to_md_layout(struct raid_set *rs,
529 unsigned int algorithm,
532 unsigned int n = 1, f = 1, r = 0;
535 * MD resilienece flaw:
537 * enabling use_far_sets for far/offset formats causes copies
538 * to be colocated on the same devs together with their origins!
540 * -> disable it for now in the definition above
542 if (algorithm == ALGORITHM_RAID10_DEFAULT ||
543 algorithm == ALGORITHM_RAID10_NEAR)
546 else if (algorithm == ALGORITHM_RAID10_OFFSET) {
549 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
550 r |= RAID10_USE_FAR_SETS;
552 } else if (algorithm == ALGORITHM_RAID10_FAR) {
555 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
556 r |= RAID10_USE_FAR_SETS;
561 return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
563 /* END: MD raid10 bit definitions and helpers */
565 /* Check for any of the raid10 algorithms */
566 static int __got_raid10(struct raid_type *rtp, const int layout)
568 if (rtp->level == 10) {
569 switch (rtp->algorithm) {
570 case ALGORITHM_RAID10_DEFAULT:
571 case ALGORITHM_RAID10_NEAR:
572 return __is_raid10_near(layout);
573 case ALGORITHM_RAID10_OFFSET:
574 return __is_raid10_offset(layout);
575 case ALGORITHM_RAID10_FAR:
576 return __is_raid10_far(layout);
585 /* Return raid_type for @name */
586 static struct raid_type *get_raid_type(const char *name)
588 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
590 while (rtp-- > raid_types)
591 if (!strcasecmp(rtp->name, name))
597 /* Return raid_type for @name based derived from @level and @layout */
598 static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
600 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
602 while (rtp-- > raid_types) {
603 /* RAID10 special checks based on @layout flags/properties */
604 if (rtp->level == level &&
605 (__got_raid10(rtp, layout) || rtp->algorithm == layout))
613 * Conditionally change bdev capacity of @rs
614 * in case of a disk add/remove reshape
616 static void rs_set_capacity(struct raid_set *rs)
618 struct mddev *mddev = &rs->md;
620 /* Make sure we access most actual mddev properties */
622 if (rs->ti->len != mddev->array_sectors && !rs_is_reshaping(rs)) {
623 struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
625 set_capacity(gendisk, mddev->array_sectors);
626 revalidate_disk(gendisk);
631 * Set the mddev properties in @rs to the current
632 * ones retrieved from the freshest superblock
634 static void rs_set_cur(struct raid_set *rs)
636 struct mddev *mddev = &rs->md;
638 mddev->new_level = mddev->level;
639 mddev->new_layout = mddev->layout;
640 mddev->new_chunk_sectors = mddev->chunk_sectors;
644 * Set the mddev properties in @rs to the new
645 * ones requested by the ctr
647 static void rs_set_new(struct raid_set *rs)
649 struct mddev *mddev = &rs->md;
651 mddev->level = mddev->new_level;
652 mddev->layout = mddev->new_layout;
653 mddev->chunk_sectors = mddev->new_chunk_sectors;
654 mddev->raid_disks = rs->raid_disks;
655 mddev->delta_disks = 0;
658 static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
664 if (raid_devs <= raid_type->parity_devs) {
665 ti->error = "Insufficient number of devices";
666 return ERR_PTR(-EINVAL);
669 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL);
671 ti->error = "Cannot allocate raid context";
672 return ERR_PTR(-ENOMEM);
677 rs->raid_disks = raid_devs;
681 rs->raid_type = raid_type;
682 rs->stripe_cache_entries = 256;
683 rs->md.raid_disks = raid_devs;
684 rs->md.level = raid_type->level;
685 rs->md.new_level = rs->md.level;
686 rs->md.layout = raid_type->algorithm;
687 rs->md.new_layout = rs->md.layout;
688 rs->md.delta_disks = 0;
689 rs->md.recovery_cp = rs_is_raid0(rs) ? MaxSector : 0;
691 for (i = 0; i < raid_devs; i++)
692 md_rdev_init(&rs->dev[i].rdev);
695 * Remaining items to be initialized by further RAID params:
698 * rs->md.chunk_sectors
699 * rs->md.new_chunk_sectors
706 static void raid_set_free(struct raid_set *rs)
710 for (i = 0; i < rs->md.raid_disks; i++) {
711 if (rs->dev[i].meta_dev)
712 dm_put_device(rs->ti, rs->dev[i].meta_dev);
713 md_rdev_clear(&rs->dev[i].rdev);
714 if (rs->dev[i].data_dev)
715 dm_put_device(rs->ti, rs->dev[i].data_dev);
722 * For every device we have two words
723 * <meta_dev>: meta device name or '-' if missing
724 * <data_dev>: data device name or '-' if missing
726 * The following are permitted:
729 * <meta_dev> <data_dev>
731 * The following is not allowed:
734 * This code parses those words. If there is a failure,
735 * the caller must use raid_set_free() to unwind the operations.
737 static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
741 int metadata_available = 0;
745 /* Put off the number of raid devices argument to get to dev pairs */
746 arg = dm_shift_arg(as);
750 for (i = 0; i < rs->md.raid_disks; i++) {
751 rs->dev[i].rdev.raid_disk = i;
753 rs->dev[i].meta_dev = NULL;
754 rs->dev[i].data_dev = NULL;
757 * There are no offsets, since there is a separate device
758 * for data and metadata.
760 rs->dev[i].rdev.data_offset = 0;
761 rs->dev[i].rdev.mddev = &rs->md;
763 arg = dm_shift_arg(as);
767 if (strcmp(arg, "-")) {
768 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
769 &rs->dev[i].meta_dev);
771 rs->ti->error = "RAID metadata device lookup failure";
775 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
776 if (!rs->dev[i].rdev.sb_page) {
777 rs->ti->error = "Failed to allocate superblock page";
782 arg = dm_shift_arg(as);
786 if (!strcmp(arg, "-")) {
787 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
788 (!rs->dev[i].rdev.recovery_offset)) {
789 rs->ti->error = "Drive designated for rebuild not specified";
793 if (rs->dev[i].meta_dev) {
794 rs->ti->error = "No data device supplied with metadata device";
801 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
802 &rs->dev[i].data_dev);
804 rs->ti->error = "RAID device lookup failure";
808 if (rs->dev[i].meta_dev) {
809 metadata_available = 1;
810 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
812 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
813 list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
814 if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
818 if (metadata_available) {
820 rs->md.persistent = 1;
821 rs->md.major_version = 2;
822 } else if (rebuild && !rs->md.recovery_cp) {
824 * Without metadata, we will not be able to tell if the array
825 * is in-sync or not - we must assume it is not. Therefore,
826 * it is impossible to rebuild a drive.
828 * Even if there is metadata, the on-disk information may
829 * indicate that the array is not in-sync and it will then
832 * User could specify 'nosync' option if desperate.
834 rs->ti->error = "Unable to rebuild drive while array is not in-sync";
842 * validate_region_size
844 * @region_size: region size in sectors. If 0, pick a size (4MiB default).
846 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
847 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
849 * Returns: 0 on success, -EINVAL on failure.
851 static int validate_region_size(struct raid_set *rs, unsigned long region_size)
853 unsigned long min_region_size = rs->ti->len / (1 << 21);
857 * Choose a reasonable default. All figures in sectors.
859 if (min_region_size > (1 << 13)) {
860 /* If not a power of 2, make it the next power of 2 */
861 region_size = roundup_pow_of_two(min_region_size);
862 DMINFO("Choosing default region size of %lu sectors",
865 DMINFO("Choosing default region size of 4MiB");
866 region_size = 1 << 13; /* sectors */
870 * Validate user-supplied value.
872 if (region_size > rs->ti->len) {
873 rs->ti->error = "Supplied region size is too large";
877 if (region_size < min_region_size) {
878 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
879 region_size, min_region_size);
880 rs->ti->error = "Supplied region size is too small";
884 if (!is_power_of_2(region_size)) {
885 rs->ti->error = "Region size is not a power of 2";
889 if (region_size < rs->md.chunk_sectors) {
890 rs->ti->error = "Region size is smaller than the chunk size";
896 * Convert sectors to bytes.
898 rs->md.bitmap_info.chunksize = (region_size << 9);
904 * validate_raid_redundancy
907 * Determine if there are enough devices in the array that haven't
908 * failed (or are being rebuilt) to form a usable array.
910 * Returns: 0 on success, -EINVAL on failure.
912 static int validate_raid_redundancy(struct raid_set *rs)
914 unsigned i, rebuild_cnt = 0;
915 unsigned rebuilds_per_group = 0, copies;
916 unsigned group_size, last_group_start;
918 for (i = 0; i < rs->md.raid_disks; i++)
919 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
920 !rs->dev[i].rdev.sb_page)
923 switch (rs->raid_type->level) {
925 if (rebuild_cnt >= rs->md.raid_disks)
931 if (rebuild_cnt > rs->raid_type->parity_devs)
935 copies = raid10_md_layout_to_copies(rs->md.new_layout);
936 if (rebuild_cnt < copies)
940 * It is possible to have a higher rebuild count for RAID10,
941 * as long as the failed devices occur in different mirror
942 * groups (i.e. different stripes).
944 * When checking "near" format, make sure no adjacent devices
945 * have failed beyond what can be handled. In addition to the
946 * simple case where the number of devices is a multiple of the
947 * number of copies, we must also handle cases where the number
948 * of devices is not a multiple of the number of copies.
949 * E.g. dev1 dev2 dev3 dev4 dev5
953 if (__is_raid10_near(rs->md.new_layout)) {
954 for (i = 0; i < rs->raid_disks; i++) {
956 rebuilds_per_group = 0;
957 if ((!rs->dev[i].rdev.sb_page ||
958 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
959 (++rebuilds_per_group >= copies))
966 * When checking "far" and "offset" formats, we need to ensure
967 * that the device that holds its copy is not also dead or
968 * being rebuilt. (Note that "far" and "offset" formats only
969 * support two copies right now. These formats also only ever
970 * use the 'use_far_sets' variant.)
972 * This check is somewhat complicated by the need to account
973 * for arrays that are not a multiple of (far) copies. This
974 * results in the need to treat the last (potentially larger)
977 group_size = (rs->md.raid_disks / copies);
978 last_group_start = (rs->md.raid_disks / group_size) - 1;
979 last_group_start *= group_size;
980 for (i = 0; i < rs->md.raid_disks; i++) {
981 if (!(i % copies) && !(i > last_group_start))
982 rebuilds_per_group = 0;
983 if ((!rs->dev[i].rdev.sb_page ||
984 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
985 (++rebuilds_per_group >= copies))
1001 * Possible arguments are...
1002 * <chunk_size> [optional_args]
1004 * Argument definitions
1005 * <chunk_size> The number of sectors per disk that
1006 * will form the "stripe"
1007 * [[no]sync] Force or prevent recovery of the
1009 * [rebuild <idx>] Rebuild the drive indicated by the index
1010 * [daemon_sleep <ms>] Time between bitmap daemon work to
1012 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1013 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1014 * [write_mostly <idx>] Indicate a write mostly drive via index
1015 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
1016 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs
1017 * [region_size <sectors>] Defines granularity of bitmap
1019 * RAID10-only options:
1020 * [raid10_copies <# copies>] Number of copies. (Default: 2)
1021 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
1023 static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
1024 unsigned num_raid_params)
1026 int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
1027 unsigned raid10_copies = 2;
1028 unsigned i, write_mostly = 0;
1029 unsigned region_size = 0;
1030 sector_t max_io_len;
1031 const char *arg, *key;
1032 struct raid_dev *rd;
1033 struct raid_type *rt = rs->raid_type;
1035 arg = dm_shift_arg(as);
1036 num_raid_params--; /* Account for chunk_size argument */
1038 if (kstrtoint(arg, 10, &value) < 0) {
1039 rs->ti->error = "Bad numerical argument given for chunk_size";
1044 * First, parse the in-order required arguments
1045 * "chunk_size" is the only argument of this type.
1047 if (rt_is_raid1(rt)) {
1049 DMERR("Ignoring chunk size parameter for RAID 1");
1051 } else if (!is_power_of_2(value)) {
1052 rs->ti->error = "Chunk size must be a power of 2";
1054 } else if (value < 8) {
1055 rs->ti->error = "Chunk size value is too small";
1059 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1062 * We set each individual device as In_sync with a completed
1063 * 'recovery_offset'. If there has been a device failure or
1064 * replacement then one of the following cases applies:
1066 * 1) User specifies 'rebuild'.
1067 * - Device is reset when param is read.
1068 * 2) A new device is supplied.
1069 * - No matching superblock found, resets device.
1070 * 3) Device failure was transient and returns on reload.
1071 * - Failure noticed, resets device for bitmap replay.
1072 * 4) Device hadn't completed recovery after previous failure.
1073 * - Superblock is read and overrides recovery_offset.
1075 * What is found in the superblocks of the devices is always
1076 * authoritative, unless 'rebuild' or '[no]sync' was specified.
1078 for (i = 0; i < rs->md.raid_disks; i++) {
1079 set_bit(In_sync, &rs->dev[i].rdev.flags);
1080 rs->dev[i].rdev.recovery_offset = MaxSector;
1084 * Second, parse the unordered optional arguments
1086 for (i = 0; i < num_raid_params; i++) {
1087 key = dm_shift_arg(as);
1089 rs->ti->error = "Not enough raid parameters given";
1093 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1094 if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1095 rs->ti->error = "Only one 'nosync' argument allowed";
1098 rs->md.recovery_cp = MaxSector;
1101 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1102 if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1103 rs->ti->error = "Only one 'sync' argument allowed";
1106 rs->md.recovery_cp = 0;
1109 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1110 if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1111 rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1117 arg = dm_shift_arg(as);
1118 i++; /* Account for the argument pairs */
1120 rs->ti->error = "Wrong number of raid parameters given";
1125 * Parameters that take a string value are checked here.
1128 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1129 if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1130 rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1133 if (!rt_is_raid10(rt)) {
1134 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1137 raid10_format = raid10_name_to_format(arg);
1138 if (raid10_format < 0) {
1139 rs->ti->error = "Invalid 'raid10_format' value given";
1140 return raid10_format;
1145 if (kstrtoint(arg, 10, &value) < 0) {
1146 rs->ti->error = "Bad numerical argument given in raid params";
1150 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1152 * "rebuild" is being passed in by userspace to provide
1153 * indexes of replaced devices and to set up additional
1154 * devices on raid level takeover.
1156 if (!__within_range(value, 0, rs->raid_disks - 1)) {
1157 rs->ti->error = "Invalid rebuild index given";
1161 if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1162 rs->ti->error = "rebuild for this index already given";
1166 rd = rs->dev + value;
1167 clear_bit(In_sync, &rd->rdev.flags);
1168 clear_bit(Faulty, &rd->rdev.flags);
1169 rd->rdev.recovery_offset = 0;
1170 set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1171 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1172 if (!rt_is_raid1(rt)) {
1173 rs->ti->error = "write_mostly option is only valid for RAID1";
1177 if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1178 rs->ti->error = "Invalid write_mostly index given";
1183 set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1184 set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1185 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1186 if (!rt_is_raid1(rt)) {
1187 rs->ti->error = "max_write_behind option is only valid for RAID1";
1191 if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1192 rs->ti->error = "Only one max_write_behind argument pair allowed";
1197 * In device-mapper, we specify things in sectors, but
1198 * MD records this value in kB
1201 if (value > COUNTER_MAX) {
1202 rs->ti->error = "Max write-behind limit out of range";
1206 rs->md.bitmap_info.max_write_behind = value;
1207 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1208 if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1209 rs->ti->error = "Only one daemon_sleep argument pair allowed";
1212 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
1213 rs->ti->error = "daemon sleep period out of range";
1216 rs->md.bitmap_info.daemon_sleep = value;
1217 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1218 /* Userspace passes new data_offset after having extended the the data image LV */
1219 if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1220 rs->ti->error = "Only one data_offset argument pair allowed";
1223 /* Ensure sensible data offset */
1225 rs->ti->error = "Bogus data_offset value";
1228 rs->data_offset = value;
1229 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1230 /* Define the +/-# of disks to add to/remove from the given raid set */
1231 if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1232 rs->ti->error = "Only one delta_disks argument pair allowed";
1235 /* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1236 if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1237 rs->ti->error = "Too many delta_disk requested";
1241 rs->delta_disks = value;
1242 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1243 if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1244 rs->ti->error = "Only one stripe_cache argument pair allowed";
1248 if (!rt_is_raid456(rt)) {
1249 rs->ti->error = "Inappropriate argument: stripe_cache";
1253 rs->stripe_cache_entries = value;
1254 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1255 if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1256 rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1259 if (value > INT_MAX) {
1260 rs->ti->error = "min_recovery_rate out of range";
1263 rs->md.sync_speed_min = (int)value;
1264 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1265 if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1266 rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1269 if (value > INT_MAX) {
1270 rs->ti->error = "max_recovery_rate out of range";
1273 rs->md.sync_speed_max = (int)value;
1274 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1275 if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1276 rs->ti->error = "Only one region_size argument pair allowed";
1280 region_size = value;
1281 rs->requested_bitmap_chunk_sectors = value;
1282 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1283 if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1284 rs->ti->error = "Only one raid10_copies argument pair allowed";
1288 if (!__within_range(value, 2, rs->md.raid_disks)) {
1289 rs->ti->error = "Bad value for 'raid10_copies'";
1293 raid10_copies = value;
1295 DMERR("Unable to parse RAID parameter: %s", key);
1296 rs->ti->error = "Unable to parse RAID parameter";
1301 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1302 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1303 rs->ti->error = "sync and nosync are mutually exclusive";
1307 if (write_mostly >= rs->md.raid_disks) {
1308 rs->ti->error = "Can't set all raid1 devices to write_mostly";
1312 if (validate_region_size(rs, region_size))
1315 if (rs->md.chunk_sectors)
1316 max_io_len = rs->md.chunk_sectors;
1318 max_io_len = region_size;
1320 if (dm_set_target_max_io_len(rs->ti, max_io_len))
1323 if (rt_is_raid10(rt)) {
1324 if (raid10_copies > rs->md.raid_disks) {
1325 rs->ti->error = "Not enough devices to satisfy specification";
1329 rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1330 if (rs->md.new_layout < 0) {
1331 rs->ti->error = "Error getting raid10 format";
1332 return rs->md.new_layout;
1335 rt = get_raid_type_by_ll(10, rs->md.new_layout);
1337 rs->ti->error = "Failed to recognize new raid10 layout";
1341 if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1342 rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1343 test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1344 rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1349 rs->raid10_copies = raid10_copies;
1351 /* Assume there are no metadata devices until the drives are parsed */
1352 rs->md.persistent = 0;
1353 rs->md.external = 1;
1355 /* Check, if any invalid ctr arguments have been passed in for the raid level */
1356 return rs_check_for_valid_flags(rs);
1359 /* Set raid4/5/6 cache size */
1360 static int rs_set_raid456_stripe_cache(struct raid_set *rs)
1363 struct r5conf *conf;
1364 struct mddev *mddev = &rs->md;
1365 uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
1366 uint32_t nr_stripes = rs->stripe_cache_entries;
1368 if (!rt_is_raid456(rs->raid_type)) {
1369 rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
1373 if (nr_stripes < min_stripes) {
1374 DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
1375 nr_stripes, min_stripes);
1376 nr_stripes = min_stripes;
1379 conf = mddev->private;
1381 rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
1385 /* Try setting number of stripes in raid456 stripe cache */
1386 if (conf->min_nr_stripes != nr_stripes) {
1387 r = raid5_set_cache_size(mddev, nr_stripes);
1389 rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
1393 DMINFO("%u stripe cache entries", nr_stripes);
1399 /* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1400 static unsigned int mddev_data_stripes(struct raid_set *rs)
1402 return rs->md.raid_disks - rs->raid_type->parity_devs;
1405 /* Return # of data stripes of @rs (i.e. as of ctr) */
1406 static unsigned int rs_data_stripes(struct raid_set *rs)
1408 return rs->raid_disks - rs->raid_type->parity_devs;
1411 /* Calculate the sectors per device and per array used for @rs */
1412 static int rs_set_dev_and_array_sectors(struct raid_set *rs, bool use_mddev)
1415 unsigned int data_stripes;
1416 struct mddev *mddev = &rs->md;
1417 struct md_rdev *rdev;
1418 sector_t array_sectors = rs->ti->len, dev_sectors = rs->ti->len;
1419 sector_t cur_dev_sectors = rs->dev[0].rdev.sectors;
1422 delta_disks = mddev->delta_disks;
1423 data_stripes = mddev_data_stripes(rs);
1425 delta_disks = rs->delta_disks;
1426 data_stripes = rs_data_stripes(rs);
1429 /* Special raid1 case w/o delta_disks support (yet) */
1430 if (rt_is_raid1(rs->raid_type))
1432 else if (rt_is_raid10(rs->raid_type)) {
1433 if (rs->raid10_copies < 2 ||
1435 rs->ti->error = "Bogus raid10 data copies or delta disks";
1439 dev_sectors *= rs->raid10_copies;
1440 if (sector_div(dev_sectors, data_stripes))
1443 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1444 if (sector_div(array_sectors, rs->raid10_copies))
1447 } else if (sector_div(dev_sectors, data_stripes))
1451 /* Striped layouts */
1452 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1454 rdev_for_each(rdev, mddev)
1455 rdev->sectors = dev_sectors;
1457 mddev->array_sectors = array_sectors;
1458 mddev->dev_sectors = dev_sectors;
1460 if (!rs_is_raid0(rs) && dev_sectors > cur_dev_sectors)
1461 mddev->recovery_cp = dev_sectors;
1465 rs->ti->error = "Target length not divisible by number of data devices";
1469 static void do_table_event(struct work_struct *ws)
1471 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1473 rs_set_capacity(rs);
1474 dm_table_event(rs->ti->table);
1477 static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
1479 struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
1481 return mddev_congested(&rs->md, bits);
1485 * Make sure a valid takover (level switch) is being requested on @rs
1487 * Conversions of raid sets from one MD personality to another
1488 * have to conform to restrictions which are enforced here.
1490 * Degration is already checked for in rs_check_conversion() below.
1492 static int rs_check_takeover(struct raid_set *rs)
1494 struct mddev *mddev = &rs->md;
1495 unsigned int near_copies;
1497 if (rs->md.degraded) {
1498 rs->ti->error = "Can't takeover degraded raid set";
1502 if (rs_is_reshaping(rs)) {
1503 rs->ti->error = "Can't takeover reshaping raid set";
1507 switch (mddev->level) {
1509 /* raid0 -> raid1/5 with one disk */
1510 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1511 mddev->raid_disks == 1)
1514 /* raid0 -> raid10 */
1515 if (mddev->new_level == 10 &&
1516 !(rs->raid_disks % mddev->raid_disks))
1519 /* raid0 with multiple disks -> raid4/5/6 */
1520 if (__within_range(mddev->new_level, 4, 6) &&
1521 mddev->new_layout == ALGORITHM_PARITY_N &&
1522 mddev->raid_disks > 1)
1528 /* Can't takeover raid10_offset! */
1529 if (__is_raid10_offset(mddev->layout))
1532 near_copies = __raid10_near_copies(mddev->layout);
1534 /* raid10* -> raid0 */
1535 if (mddev->new_level == 0) {
1536 /* Can takeover raid10_near with raid disks divisable by data copies! */
1537 if (near_copies > 1 &&
1538 !(mddev->raid_disks % near_copies)) {
1539 mddev->raid_disks /= near_copies;
1540 mddev->delta_disks = mddev->raid_disks;
1544 /* Can takeover raid10_far */
1545 if (near_copies == 1 &&
1546 __raid10_far_copies(mddev->layout) > 1)
1552 /* raid10_{near,far} -> raid1 */
1553 if (mddev->new_level == 1 &&
1554 max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1557 /* raid10_{near,far} with 2 disks -> raid4/5 */
1558 if (__within_range(mddev->new_level, 4, 5) &&
1559 mddev->raid_disks == 2)
1564 /* raid1 with 2 disks -> raid4/5 */
1565 if (__within_range(mddev->new_level, 4, 5) &&
1566 mddev->raid_disks == 2) {
1567 mddev->degraded = 1;
1571 /* raid1 -> raid0 */
1572 if (mddev->new_level == 0 &&
1573 mddev->raid_disks == 1)
1576 /* raid1 -> raid10 */
1577 if (mddev->new_level == 10)
1583 /* raid4 -> raid0 */
1584 if (mddev->new_level == 0)
1587 /* raid4 -> raid1/5 with 2 disks */
1588 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1589 mddev->raid_disks == 2)
1592 /* raid4 -> raid5/6 with parity N */
1593 if (__within_range(mddev->new_level, 5, 6) &&
1594 mddev->layout == ALGORITHM_PARITY_N)
1599 /* raid5 with parity N -> raid0 */
1600 if (mddev->new_level == 0 &&
1601 mddev->layout == ALGORITHM_PARITY_N)
1604 /* raid5 with parity N -> raid4 */
1605 if (mddev->new_level == 4 &&
1606 mddev->layout == ALGORITHM_PARITY_N)
1609 /* raid5 with 2 disks -> raid1/4/10 */
1610 if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1611 mddev->raid_disks == 2)
1614 /* raid5 with parity N -> raid6 with parity N */
1615 if (mddev->new_level == 6 &&
1616 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1617 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1622 /* raid6 with parity N -> raid0 */
1623 if (mddev->new_level == 0 &&
1624 mddev->layout == ALGORITHM_PARITY_N)
1627 /* raid6 with parity N -> raid4 */
1628 if (mddev->new_level == 4 &&
1629 mddev->layout == ALGORITHM_PARITY_N)
1632 /* raid6_*_n with parity N -> raid5_* */
1633 if (mddev->new_level == 5 &&
1634 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1635 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1642 rs->ti->error = "takeover not possible";
1646 /* True if @rs requested to be taken over */
1647 static bool rs_takeover_requested(struct raid_set *rs)
1649 return rs->md.new_level != rs->md.level;
1652 /* True if @rs is requested to reshape by ctr */
1653 static bool rs_reshape_requested(struct raid_set *rs)
1655 struct mddev *mddev = &rs->md;
1660 return !__is_raid10_far(mddev->new_layout) &&
1661 mddev->new_level == mddev->level &&
1662 (mddev->new_layout != mddev->layout ||
1663 mddev->new_chunk_sectors != mddev->chunk_sectors ||
1664 rs->raid_disks + rs->delta_disks != mddev->raid_disks);
1668 #define FEATURE_FLAG_SUPPORTS_V190 0x1 /* Supports extended superblock */
1670 /* State flags for sb->flags */
1671 #define SB_FLAG_RESHAPE_ACTIVE 0x1
1672 #define SB_FLAG_RESHAPE_BACKWARDS 0x2
1675 * This structure is never routinely used by userspace, unlike md superblocks.
1676 * Devices with this superblock should only ever be accessed via device-mapper.
1678 #define DM_RAID_MAGIC 0x64526D44
1679 struct dm_raid_superblock {
1680 __le32 magic; /* "DmRd" */
1681 __le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1683 __le32 num_devices; /* Number of devices in this raid set. (Max 64) */
1684 __le32 array_position; /* The position of this drive in the raid set */
1686 __le64 events; /* Incremented by md when superblock updated */
1687 __le64 failed_devices; /* Pre 1.9.0 part of bit field of devices to */
1688 /* indicate failures (see extension below) */
1691 * This offset tracks the progress of the repair or replacement of
1692 * an individual drive.
1694 __le64 disk_recovery_offset;
1697 * This offset tracks the progress of the initial raid set
1698 * synchronisation/parity calculation.
1700 __le64 array_resync_offset;
1703 * raid characteristics
1707 __le32 stripe_sectors;
1709 /********************************************************************
1710 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1712 * FEATURE_FLAG_SUPPORTS_V190 in the features member indicates that those exist
1715 __le32 flags; /* Flags defining array states for reshaping */
1718 * This offset tracks the progress of a raid
1719 * set reshape in order to be able to restart it
1721 __le64 reshape_position;
1724 * These define the properties of the array in case of an interrupted reshape
1728 __le32 new_stripe_sectors;
1731 __le64 array_sectors; /* Array size in sectors */
1734 * Sector offsets to data on devices (reshaping).
1735 * Needed to support out of place reshaping, thus
1736 * not writing over any stripes whilst converting
1737 * them from old to new layout
1740 __le64 new_data_offset;
1742 __le64 sectors; /* Used device size in sectors */
1745 * Additonal Bit field of devices indicating failures to support
1746 * up to 256 devices with the 1.9.0 on-disk metadata format
1748 __le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
1750 __le32 incompat_features; /* Used to indicate any incompatible features */
1752 /* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
1756 * Check for reshape constraints on raid set @rs:
1758 * - reshape function non-existent
1760 * - ongoing recovery
1763 * Returns 0 if none or -EPERM if given constraint
1764 * and error message reference in @errmsg
1766 static int rs_check_reshape(struct raid_set *rs)
1768 struct mddev *mddev = &rs->md;
1770 if (!mddev->pers || !mddev->pers->check_reshape)
1771 rs->ti->error = "Reshape not supported";
1772 else if (mddev->degraded)
1773 rs->ti->error = "Can't reshape degraded raid set";
1774 else if (rs_is_recovering(rs))
1775 rs->ti->error = "Convert request on recovering raid set prohibited";
1776 else if (mddev->reshape_position && rs_is_reshaping(rs))
1777 rs->ti->error = "raid set already reshaping!";
1778 else if (!(rs_is_raid10(rs) || rs_is_raid456(rs)))
1779 rs->ti->error = "Reshaping only supported for raid4/5/6/10";
1786 static int read_disk_sb(struct md_rdev *rdev, int size)
1788 BUG_ON(!rdev->sb_page);
1790 if (rdev->sb_loaded)
1793 if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, true)) {
1794 DMERR("Failed to read superblock of device at position %d",
1796 md_error(rdev->mddev, rdev);
1800 rdev->sb_loaded = 1;
1805 static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1807 failed_devices[0] = le64_to_cpu(sb->failed_devices);
1808 memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
1810 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
1811 int i = ARRAY_SIZE(sb->extended_failed_devices);
1814 failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
1818 static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1820 int i = ARRAY_SIZE(sb->extended_failed_devices);
1822 sb->failed_devices = cpu_to_le64(failed_devices[0]);
1824 sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
1828 * Synchronize the superblock members with the raid set properties
1830 * All superblock data is little endian.
1832 static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
1834 bool update_failed_devices = false;
1836 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
1837 struct dm_raid_superblock *sb;
1838 struct raid_set *rs = container_of(mddev, struct raid_set, md);
1840 /* No metadata device, no superblock */
1841 if (!rdev->meta_bdev)
1844 BUG_ON(!rdev->sb_page);
1846 sb = page_address(rdev->sb_page);
1848 sb_retrieve_failed_devices(sb, failed_devices);
1850 for (i = 0; i < rs->raid_disks; i++)
1851 if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
1852 update_failed_devices = true;
1853 set_bit(i, (void *) failed_devices);
1856 if (update_failed_devices)
1857 sb_update_failed_devices(sb, failed_devices);
1859 sb->magic = cpu_to_le32(DM_RAID_MAGIC);
1860 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
1862 sb->num_devices = cpu_to_le32(mddev->raid_disks);
1863 sb->array_position = cpu_to_le32(rdev->raid_disk);
1865 sb->events = cpu_to_le64(mddev->events);
1867 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
1868 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
1870 sb->level = cpu_to_le32(mddev->level);
1871 sb->layout = cpu_to_le32(mddev->layout);
1872 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
1874 sb->new_level = cpu_to_le32(mddev->new_level);
1875 sb->new_layout = cpu_to_le32(mddev->new_layout);
1876 sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
1878 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1880 smp_rmb(); /* Make sure we access most recent reshape position */
1881 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1882 if (le64_to_cpu(sb->reshape_position) != MaxSector) {
1883 /* Flag ongoing reshape */
1884 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
1886 if (mddev->delta_disks < 0 || mddev->reshape_backwards)
1887 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
1889 /* Clear reshape flags */
1890 sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
1893 sb->array_sectors = cpu_to_le64(mddev->array_sectors);
1894 sb->data_offset = cpu_to_le64(rdev->data_offset);
1895 sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
1896 sb->sectors = cpu_to_le64(rdev->sectors);
1898 /* Zero out the rest of the payload after the size of the superblock */
1899 memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
1905 * This function creates a superblock if one is not found on the device
1906 * and will decide which superblock to use if there's a choice.
1908 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
1910 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
1913 struct dm_raid_superblock *sb;
1914 struct dm_raid_superblock *refsb;
1915 uint64_t events_sb, events_refsb;
1918 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
1919 if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) {
1920 DMERR("superblock size of a logical block is no longer valid");
1924 r = read_disk_sb(rdev, rdev->sb_size);
1928 sb = page_address(rdev->sb_page);
1931 * Two cases that we want to write new superblocks and rebuild:
1932 * 1) New device (no matching magic number)
1933 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
1935 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
1936 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
1937 super_sync(rdev->mddev, rdev);
1939 set_bit(FirstUse, &rdev->flags);
1940 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
1942 /* Force writing of superblocks to disk */
1943 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags);
1945 /* Any superblock is better than none, choose that if given */
1946 return refdev ? 0 : 1;
1952 events_sb = le64_to_cpu(sb->events);
1954 refsb = page_address(refdev->sb_page);
1955 events_refsb = le64_to_cpu(refsb->events);
1957 return (events_sb > events_refsb) ? 1 : 0;
1960 static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
1964 struct mddev *mddev = &rs->md;
1966 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
1967 struct dm_raid_superblock *sb;
1968 uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
1970 struct dm_raid_superblock *sb2;
1972 sb = page_address(rdev->sb_page);
1973 events_sb = le64_to_cpu(sb->events);
1976 * Initialise to 1 if this is a new superblock.
1978 mddev->events = events_sb ? : 1;
1980 mddev->reshape_position = MaxSector;
1983 * Reshaping is supported, e.g. reshape_position is valid
1984 * in superblock and superblock content is authoritative.
1986 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
1987 /* Superblock is authoritative wrt given raid set layout! */
1988 mddev->raid_disks = le32_to_cpu(sb->num_devices);
1989 mddev->level = le32_to_cpu(sb->level);
1990 mddev->layout = le32_to_cpu(sb->layout);
1991 mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
1992 mddev->new_level = le32_to_cpu(sb->new_level);
1993 mddev->new_layout = le32_to_cpu(sb->new_layout);
1994 mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
1995 mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1996 mddev->array_sectors = le64_to_cpu(sb->array_sectors);
1998 /* raid was reshaping and got interrupted */
1999 if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2000 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2001 DMERR("Reshape requested but raid set is still reshaping");
2005 if (mddev->delta_disks < 0 ||
2006 (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2007 mddev->reshape_backwards = 1;
2009 mddev->reshape_backwards = 0;
2011 mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2012 rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
2017 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2019 if (le32_to_cpu(sb->level) != mddev->level) {
2020 DMERR("Reshaping/takeover raid sets not yet supported. (raid level/stripes/size change)");
2023 if (le32_to_cpu(sb->layout) != mddev->layout) {
2024 DMERR("Reshaping raid sets not yet supported. (raid layout change)");
2025 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout);
2026 DMERR(" Old layout: %s w/ %d copies",
2027 raid10_md_layout_to_format(le32_to_cpu(sb->layout)),
2028 raid10_md_layout_to_copies(le32_to_cpu(sb->layout)));
2029 DMERR(" New layout: %s w/ %d copies",
2030 raid10_md_layout_to_format(mddev->layout),
2031 raid10_md_layout_to_copies(mddev->layout));
2034 if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) {
2035 DMERR("Reshaping raid sets not yet supported. (stripe sectors change)");
2039 /* We can only change the number of devices in raid1 with old (i.e. pre 1.0.7) metadata */
2040 if (!rt_is_raid1(rs->raid_type) &&
2041 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) {
2042 DMERR("Reshaping raid sets not yet supported. (device count change from %u to %u)",
2043 sb->num_devices, mddev->raid_disks);
2047 /* Table line is checked vs. authoritative superblock */
2051 if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2052 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2055 * During load, we set FirstUse if a new superblock was written.
2056 * There are two reasons we might not have a superblock:
2057 * 1) The raid set is brand new - in which case, all of the
2058 * devices must have their In_sync bit set. Also,
2059 * recovery_cp must be 0, unless forced.
2060 * 2) This is a new device being added to an old raid set
2061 * and the new device needs to be rebuilt - in which
2062 * case the In_sync bit will /not/ be set and
2063 * recovery_cp must be MaxSector.
2064 * 3) This is/are a new device(s) being added to an old
2065 * raid set during takeover to a higher raid level
2066 * to provide capacity for redundancy or during reshape
2067 * to add capacity to grow the raid set.
2070 rdev_for_each(r, mddev) {
2071 if (test_bit(FirstUse, &r->flags))
2074 if (!test_bit(In_sync, &r->flags)) {
2075 DMINFO("Device %d specified for rebuild; clearing superblock",
2079 if (test_bit(FirstUse, &r->flags))
2086 if (new_devs == rs->raid_disks || !rebuilds) {
2087 /* Replace a broken device */
2088 if (new_devs == 1 && !rs->delta_disks)
2090 if (new_devs == rs->raid_disks) {
2091 DMINFO("Superblocks created for new raid set");
2092 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2093 mddev->recovery_cp = 0;
2094 } else if (new_devs != rebuilds &&
2095 new_devs != rs->delta_disks) {
2096 DMERR("New device injected into existing raid set without "
2097 "'delta_disks' or 'rebuild' parameter specified");
2100 } else if (new_devs && new_devs != rebuilds) {
2101 DMERR("%u 'rebuild' devices cannot be injected into"
2102 " a raid set with %u other first-time devices",
2103 rebuilds, new_devs);
2105 } else if (rebuilds) {
2106 if (rebuild_and_new && rebuilds != rebuild_and_new) {
2107 DMERR("new device%s provided without 'rebuild'",
2108 new_devs > 1 ? "s" : "");
2110 } else if (rs_is_recovering(rs)) {
2111 DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2112 (unsigned long long) mddev->recovery_cp);
2114 } else if (rs_is_reshaping(rs)) {
2115 DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2116 (unsigned long long) mddev->reshape_position);
2122 * Now we set the Faulty bit for those devices that are
2123 * recorded in the superblock as failed.
2125 sb_retrieve_failed_devices(sb, failed_devices);
2126 rdev_for_each(r, mddev) {
2129 sb2 = page_address(r->sb_page);
2130 sb2->failed_devices = 0;
2131 memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2134 * Check for any device re-ordering.
2136 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2137 role = le32_to_cpu(sb2->array_position);
2141 if (role != r->raid_disk) {
2142 if (__is_raid10_near(mddev->layout)) {
2143 if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2144 rs->raid_disks % rs->raid10_copies) {
2146 "Cannot change raid10 near set to odd # of devices!";
2150 sb2->array_position = cpu_to_le32(r->raid_disk);
2152 } else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2153 !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2154 !rt_is_raid1(rs->raid_type)) {
2155 rs->ti->error = "Cannot change device positions in raid set";
2159 DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2163 * Partial recovery is performed on
2164 * returning failed devices.
2166 if (test_bit(role, (void *) failed_devices))
2167 set_bit(Faulty, &r->flags);
2174 static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2176 struct mddev *mddev = &rs->md;
2177 struct dm_raid_superblock *sb;
2179 if (rs_is_raid0(rs) || !rdev->sb_page)
2182 sb = page_address(rdev->sb_page);
2185 * If mddev->events is not set, we know we have not yet initialized
2188 if (!mddev->events && super_init_validation(rs, rdev))
2191 if (le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2192 rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2196 if (sb->incompat_features) {
2197 rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2201 /* Enable bitmap creation for RAID levels != 0 */
2202 mddev->bitmap_info.offset = rt_is_raid0(rs->raid_type) ? 0 : to_sector(4096);
2203 rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2205 if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2206 /* Retrieve device size stored in superblock to be prepared for shrink */
2207 rdev->sectors = le64_to_cpu(sb->sectors);
2208 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2209 if (rdev->recovery_offset == MaxSector)
2210 set_bit(In_sync, &rdev->flags);
2212 * If no reshape in progress -> we're recovering single
2213 * disk(s) and have to set the device(s) to out-of-sync
2215 else if (!rs_is_reshaping(rs))
2216 clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2220 * If a device comes back, set it as not In_sync and no longer faulty.
2222 if (test_and_clear_bit(Faulty, &rdev->flags)) {
2223 rdev->recovery_offset = 0;
2224 clear_bit(In_sync, &rdev->flags);
2225 rdev->saved_raid_disk = rdev->raid_disk;
2228 /* Reshape support -> restore repective data offsets */
2229 rdev->data_offset = le64_to_cpu(sb->data_offset);
2230 rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2236 * Analyse superblocks and select the freshest.
2238 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2241 struct raid_dev *dev;
2242 struct md_rdev *rdev, *tmp, *freshest;
2243 struct mddev *mddev = &rs->md;
2246 rdev_for_each_safe(rdev, tmp, mddev) {
2248 * Skipping super_load due to CTR_FLAG_SYNC will cause
2249 * the array to undergo initialization again as
2250 * though it were new. This is the intended effect
2251 * of the "sync" directive.
2253 * When reshaping capability is added, we must ensure
2254 * that the "sync" directive is disallowed during the
2257 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2260 if (!rdev->meta_bdev)
2263 r = super_load(rdev, freshest);
2272 dev = container_of(rdev, struct raid_dev, rdev);
2274 dm_put_device(ti, dev->meta_dev);
2276 dev->meta_dev = NULL;
2277 rdev->meta_bdev = NULL;
2280 put_page(rdev->sb_page);
2282 rdev->sb_page = NULL;
2284 rdev->sb_loaded = 0;
2287 * We might be able to salvage the data device
2288 * even though the meta device has failed. For
2289 * now, we behave as though '- -' had been
2290 * set for this device in the table.
2293 dm_put_device(ti, dev->data_dev);
2295 dev->data_dev = NULL;
2298 list_del(&rdev->same_set);
2305 if (validate_raid_redundancy(rs)) {
2306 rs->ti->error = "Insufficient redundancy to activate array";
2311 * Validation of the freshest device provides the source of
2312 * validation for the remaining devices.
2314 rs->ti->error = "Unable to assemble array: Invalid superblocks";
2315 if (super_validate(rs, freshest))
2318 rdev_for_each(rdev, mddev)
2319 if ((rdev != freshest) && super_validate(rs, rdev))
2325 * Adjust data_offset and new_data_offset on all disk members of @rs
2326 * for out of place reshaping if requested by contructor
2328 * We need free space at the beginning of each raid disk for forward
2329 * and at the end for backward reshapes which userspace has to provide
2330 * via remapping/reordering of space.
2332 static int rs_adjust_data_offsets(struct raid_set *rs)
2334 sector_t data_offset = 0, new_data_offset = 0;
2335 struct md_rdev *rdev;
2337 /* Constructor did not request data offset change */
2338 if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2339 if (!rs_is_reshapable(rs))
2345 /* HM FIXME: get InSync raid_dev? */
2346 rdev = &rs->dev[0].rdev;
2348 if (rs->delta_disks < 0) {
2350 * Removing disks (reshaping backwards):
2352 * - before reshape: data is at offset 0 and free space
2353 * is at end of each component LV
2355 * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2358 new_data_offset = rs->data_offset;
2360 } else if (rs->delta_disks > 0) {
2362 * Adding disks (reshaping forwards):
2364 * - before reshape: data is at offset rs->data_offset != 0 and
2365 * free space is at begin of each component LV
2367 * - after reshape: data is at offset 0 on each component LV
2369 data_offset = rs->data_offset;
2370 new_data_offset = 0;
2374 * User space passes in 0 for data offset after having removed reshape space
2376 * - or - (data offset != 0)
2378 * Changing RAID layout or chunk size -> toggle offsets
2380 * - before reshape: data is at offset rs->data_offset 0 and
2381 * free space is at end of each component LV
2383 * data is at offset rs->data_offset != 0 and
2384 * free space is at begin of each component LV
2386 * - after reshape: data is at offset 0 if i was at offset != 0
2387 * of at offset != 0 if it was at offset 0
2388 * on each component LV
2391 data_offset = rs->data_offset ? rdev->data_offset : 0;
2392 new_data_offset = data_offset ? 0 : rs->data_offset;
2393 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2397 * Make sure we got a minimum amount of free sectors per device
2399 if (rs->data_offset &&
2400 to_sector(i_size_read(rdev->bdev->bd_inode)) - rdev->sectors < MIN_FREE_RESHAPE_SPACE) {
2401 rs->ti->error = data_offset ? "No space for forward reshape" :
2402 "No space for backward reshape";
2406 /* Adjust data offsets on all rdevs */
2407 rdev_for_each(rdev, &rs->md) {
2408 rdev->data_offset = data_offset;
2409 rdev->new_data_offset = new_data_offset;
2415 /* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2416 static void __reorder_raid_disk_indexes(struct raid_set *rs)
2419 struct md_rdev *rdev;
2421 rdev_for_each(rdev, &rs->md) {
2422 rdev->raid_disk = i++;
2423 rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2428 * Setup @rs for takeover by a different raid level
2430 static int rs_setup_takeover(struct raid_set *rs)
2432 struct mddev *mddev = &rs->md;
2433 struct md_rdev *rdev;
2434 unsigned int d = mddev->raid_disks = rs->raid_disks;
2435 sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2437 if (rt_is_raid10(rs->raid_type)) {
2438 if (mddev->level == 0) {
2439 /* Userpace reordered disks -> adjust raid_disk indexes */
2440 __reorder_raid_disk_indexes(rs);
2442 /* raid0 -> raid10_far layout */
2443 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2445 } else if (mddev->level == 1)
2446 /* raid1 -> raid10_near layout */
2447 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2454 clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2455 mddev->recovery_cp = MaxSector;
2458 rdev = &rs->dev[d].rdev;
2460 if (test_bit(d, (void *) rs->rebuild_disks)) {
2461 clear_bit(In_sync, &rdev->flags);
2462 clear_bit(Faulty, &rdev->flags);
2463 mddev->recovery_cp = rdev->recovery_offset = 0;
2464 /* Bitmap has to be created when we do an "up" takeover */
2465 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2468 rdev->new_data_offset = new_data_offset;
2476 * - change raid layout
2477 * - change chunk size
2481 static int rs_setup_reshape(struct raid_set *rs)
2484 unsigned int cur_raid_devs, d;
2485 struct mddev *mddev = &rs->md;
2486 struct md_rdev *rdev;
2488 mddev->delta_disks = rs->delta_disks;
2489 cur_raid_devs = mddev->raid_disks;
2491 /* Ignore impossible layout change whilst adding/removing disks */
2492 if (mddev->delta_disks &&
2493 mddev->layout != mddev->new_layout) {
2494 DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2495 mddev->new_layout = mddev->layout;
2499 * Adjust array size:
2501 * - in case of adding disks, array size has
2502 * to grow after the disk adding reshape,
2503 * which'll hapen in the event handler;
2504 * reshape will happen forward, so space has to
2505 * be available at the beginning of each disk
2507 * - in case of removing disks, array size
2508 * has to shrink before starting the reshape,
2509 * which'll happen here;
2510 * reshape will happen backward, so space has to
2511 * be available at the end of each disk
2513 * - data_offset and new_data_offset are
2514 * adjusted for afreentioned out of place
2515 * reshaping based on userspace passing in
2516 * the "data_offset <sectors>" key/value
2517 * pair via te constructor
2521 if (rs->delta_disks > 0) {
2522 /* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2523 for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2524 rdev = &rs->dev[d].rdev;
2525 clear_bit(In_sync, &rdev->flags);
2528 * save_raid_disk needs to be -1, or recovery_offset will be set to 0
2529 * by md, which'll store that erroneously in the superblock on reshape
2531 rdev->saved_raid_disk = -1;
2532 rdev->raid_disk = d;
2534 rdev->sectors = mddev->dev_sectors;
2535 rdev->recovery_offset = MaxSector;
2538 mddev->reshape_backwards = 0; /* adding disks -> forward reshape */
2540 /* Remove disk(s) */
2541 } else if (rs->delta_disks < 0) {
2542 r = rs_set_dev_and_array_sectors(rs, true);
2543 mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2545 /* Change layout and/or chunk size */
2548 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2550 * keeping number of disks and do layout change ->
2552 * toggle reshape_backward depending on data_offset:
2554 * - free space upfront -> reshape forward
2556 * - free space at the end -> reshape backward
2559 * This utilizes free reshape space avoiding the need
2560 * for userspace to move (parts of) LV segments in
2561 * case of layout/chunksize change (for disk
2562 * adding/removing reshape space has to be at
2563 * the proper address (see above with delta_disks):
2565 * add disk(s) -> begin
2566 * remove disk(s)-> end
2568 mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2575 * Enable/disable discard support on RAID set depending on
2576 * RAID level and discard properties of underlying RAID members.
2578 static void configure_discard_support(struct raid_set *rs)
2582 struct dm_target *ti = rs->ti;
2584 /* Assume discards not supported until after checks below. */
2585 ti->discards_supported = false;
2587 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */
2588 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6);
2590 for (i = 0; i < rs->md.raid_disks; i++) {
2591 struct request_queue *q;
2593 if (!rs->dev[i].rdev.bdev)
2596 q = bdev_get_queue(rs->dev[i].rdev.bdev);
2597 if (!q || !blk_queue_discard(q))
2601 if (!q->limits.discard_zeroes_data)
2603 if (!devices_handle_discard_safely) {
2604 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2605 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2611 /* All RAID members properly support discards */
2612 ti->discards_supported = true;
2615 * RAID1 and RAID10 personalities require bio splitting,
2616 * RAID0/4/5/6 don't and process large discard bios properly.
2618 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10);
2619 ti->num_discard_bios = 1;
2623 * Construct a RAID0/1/10/4/5/6 mapping:
2625 * <raid_type> <#raid_params> <raid_params>{0,} \
2626 * <#raid_devs> [<meta_dev1> <dev1>]{1,}
2628 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for
2629 * details on possible <raid_params>.
2631 * Userspace is free to initialize the metadata devices, hence the superblocks to
2632 * enforce recreation based on the passed in table parameters.
2635 static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv)
2638 struct raid_type *rt;
2639 unsigned num_raid_params, num_raid_devs;
2640 struct raid_set *rs = NULL;
2642 struct rs_layout rs_layout;
2643 struct dm_arg_set as = { argc, argv }, as_nrd;
2644 struct dm_arg _args[] = {
2645 { 0, as.argc, "Cannot understand number of raid parameters" },
2646 { 1, 254, "Cannot understand number of raid devices parameters" }
2649 /* Must have <raid_type> */
2650 arg = dm_shift_arg(&as);
2652 ti->error = "No arguments";
2656 rt = get_raid_type(arg);
2658 ti->error = "Unrecognised raid_type";
2662 /* Must have <#raid_params> */
2663 if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
2666 /* number of raid device tupples <meta_dev data_dev> */
2668 dm_consume_args(&as_nrd, num_raid_params);
2669 _args[1].max = (as_nrd.argc - 1) / 2;
2670 if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
2673 if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
2674 ti->error = "Invalid number of supplied raid devices";
2678 rs = raid_set_alloc(ti, rt, num_raid_devs);
2682 r = parse_raid_params(rs, &as, num_raid_params);
2686 r = parse_dev_params(rs, &as);
2690 rs->md.sync_super = super_sync;
2692 r = rs_set_dev_and_array_sectors(rs, false);
2697 * Backup any new raid set level, layout, ...
2698 * requested to be able to compare to superblock
2699 * members for conversion decisions.
2701 rs_config_backup(rs, &rs_layout);
2703 r = analyse_superblocks(ti, rs);
2707 INIT_WORK(&rs->md.event_work, do_table_event);
2709 ti->num_flush_bios = 1;
2711 /* Restore any requested new layout for conversion decision */
2712 rs_config_restore(rs, &rs_layout);
2714 if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
2715 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2717 } else if (rs_is_reshaping(rs))
2718 ; /* skip rs setup */
2719 else if (rs_takeover_requested(rs)) {
2720 if (rs_is_reshaping(rs)) {
2721 ti->error = "Can't takeover a reshaping raid set";
2726 * If a takeover is needed, just set the level to
2727 * the new requested one and allow the raid set to run.
2729 r = rs_check_takeover(rs);
2733 r = rs_setup_takeover(rs);
2737 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2738 set_bit(RT_FLAG_KEEP_RS_FROZEN, &rs->runtime_flags);
2740 } else if (rs_reshape_requested(rs)) {
2741 if (rs_is_reshaping(rs)) {
2742 ti->error = "raid set already reshaping!";
2746 if (rs_is_raid10(rs)) {
2747 if (rs->raid_disks != rs->md.raid_disks &&
2748 __is_raid10_near(rs->md.layout) &&
2749 rs->raid10_copies &&
2750 rs->raid10_copies != __raid10_near_copies(rs->md.layout)) {
2752 * raid disk have to be multiple of data copies to allow this conversion,
2754 * This is actually not a reshape it is a
2755 * rebuild of any additional mirrors per group
2757 if (rs->raid_disks % rs->raid10_copies) {
2758 ti->error = "Can't reshape raid10 mirror groups";
2762 /* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2763 __reorder_raid_disk_indexes(rs);
2764 rs->md.layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2766 rs->md.new_layout = rs->md.layout;
2769 set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2771 } else if (rs_is_raid456(rs))
2772 set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2775 * HM FIXME: process raid1 via delta_disks as well?
2776 * Would cause allocations in raid1->check_reshape
2777 * though, thus more issues with potential failures
2779 else if (rs_is_raid1(rs)) {
2780 set_bit(RT_FLAG_KEEP_RS_FROZEN, &rs->runtime_flags);
2781 rs->md.raid_disks = rs->raid_disks;
2784 if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
2785 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2786 set_bit(RT_FLAG_KEEP_RS_FROZEN, &rs->runtime_flags);
2789 if (rs->md.raid_disks < rs->raid_disks)
2790 set_bit(MD_ARRAY_FIRST_USE, &rs->md.flags);
2796 /* If constructor requested it, change data and new_data offsets */
2797 r = rs_adjust_data_offsets(rs);
2801 /* Start raid set read-only and assumed clean to change in raid_resume() */
2804 set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
2806 /* Has to be held on running the array */
2807 mddev_lock_nointr(&rs->md);
2808 r = md_run(&rs->md);
2809 rs->md.in_sync = 0; /* Assume already marked dirty */
2812 ti->error = "Failed to run raid array";
2813 mddev_unlock(&rs->md);
2817 rs->callbacks.congested_fn = raid_is_congested;
2818 dm_table_add_target_callbacks(ti->table, &rs->callbacks);
2820 mddev_suspend(&rs->md);
2822 /* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
2823 if (rs_is_raid456(rs)) {
2824 r = rs_set_raid456_stripe_cache(rs);
2826 goto bad_stripe_cache;
2829 /* Now do an early reshape check */
2830 if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
2831 r = rs_check_reshape(rs);
2835 /* Restore new, ctr requested layout to perform check */
2836 rs_config_restore(rs, &rs_layout);
2838 r = rs->md.pers->check_reshape(&rs->md);
2840 ti->error = "Reshape check failed";
2841 goto bad_check_reshape;
2845 mddev_unlock(&rs->md);
2857 static void raid_dtr(struct dm_target *ti)
2859 struct raid_set *rs = ti->private;
2861 list_del_init(&rs->callbacks.list);
2866 static int raid_map(struct dm_target *ti, struct bio *bio)
2868 struct raid_set *rs = ti->private;
2869 struct mddev *mddev = &rs->md;
2872 * If we're reshaping to add disk(s)), ti->len and
2873 * mddev->array_sectors will differ during the process
2874 * (ti->len > mddev->array_sectors), so we have to requeue
2875 * bios with addresses > mddev->array_sectors here or
2876 * or there will occur accesses past EOD of the component
2877 * data images thus erroring the raid set.
2879 if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
2880 return DM_MAPIO_REQUEUE;
2882 mddev->pers->make_request(mddev, bio);
2884 return DM_MAPIO_SUBMITTED;
2887 /* Return string describing the current sync action of @mddev */
2888 static const char *decipher_sync_action(struct mddev *mddev)
2890 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
2893 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2894 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
2895 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
2898 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
2899 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2901 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
2906 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
2914 * Return status string @rdev
2916 * Status characters:
2918 * 'D' = Dead/Failed device
2919 * 'a' = Alive but not in-sync
2920 * 'A' = Alive and in-sync
2922 static const char *__raid_dev_status(struct md_rdev *rdev, bool array_in_sync)
2924 if (test_bit(Faulty, &rdev->flags))
2926 else if (!array_in_sync || !test_bit(In_sync, &rdev->flags))
2932 /* Helper to return resync/reshape progress for @rs and @array_in_sync */
2933 static sector_t rs_get_progress(struct raid_set *rs,
2934 sector_t resync_max_sectors, bool *array_in_sync)
2936 sector_t r, recovery_cp, curr_resync_completed;
2937 struct mddev *mddev = &rs->md;
2939 curr_resync_completed = mddev->curr_resync_completed ?: mddev->recovery_cp;
2940 recovery_cp = mddev->recovery_cp;
2941 *array_in_sync = false;
2943 if (rs_is_raid0(rs)) {
2944 r = resync_max_sectors;
2945 *array_in_sync = true;
2948 r = mddev->reshape_position;
2950 /* Reshape is relative to the array size */
2951 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ||
2953 if (r == MaxSector) {
2954 *array_in_sync = true;
2955 r = resync_max_sectors;
2957 /* Got to reverse on backward reshape */
2958 if (mddev->reshape_backwards)
2959 r = mddev->array_sectors - r;
2961 /* Devide by # of data stripes */
2962 sector_div(r, mddev_data_stripes(rs));
2965 /* Sync is relative to the component device size */
2966 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2967 r = curr_resync_completed;
2971 if (r == MaxSector) {
2975 *array_in_sync = true;
2976 r = resync_max_sectors;
2977 } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2979 * If "check" or "repair" is occurring, the raid set has
2980 * undergone an initial sync and the health characters
2981 * should not be 'a' anymore.
2983 *array_in_sync = true;
2985 struct md_rdev *rdev;
2988 * The raid set may be doing an initial sync, or it may
2989 * be rebuilding individual components. If all the
2990 * devices are In_sync, then it is the raid set that is
2991 * being initialized.
2993 rdev_for_each(rdev, mddev)
2994 if (!test_bit(In_sync, &rdev->flags))
2995 *array_in_sync = true;
2997 r = 0; /* HM FIXME: TESTME: https://bugzilla.redhat.com/show_bug.cgi?id=1210637 ? */
3005 /* Helper to return @dev name or "-" if !@dev */
3006 static const char *__get_dev_name(struct dm_dev *dev)
3008 return dev ? dev->name : "-";
3011 static void raid_status(struct dm_target *ti, status_type_t type,
3012 unsigned int status_flags, char *result, unsigned int maxlen)
3014 struct raid_set *rs = ti->private;
3015 struct mddev *mddev = &rs->md;
3016 struct r5conf *conf = mddev->private;
3017 int max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3019 unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3020 unsigned int sz = 0;
3021 unsigned int write_mostly_params = 0;
3022 sector_t progress, resync_max_sectors, resync_mismatches;
3023 const char *sync_action;
3024 struct raid_type *rt;
3025 struct md_rdev *rdev;
3028 case STATUSTYPE_INFO:
3029 /* *Should* always succeed */
3030 rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3034 DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3036 /* Access most recent mddev properties for status output */
3038 /* Get sensible max sectors even if raid set not yet started */
3039 resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3040 mddev->resync_max_sectors : mddev->dev_sectors;
3041 progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync);
3042 resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
3043 atomic64_read(&mddev->resync_mismatches) : 0;
3044 sync_action = decipher_sync_action(&rs->md);
3046 /* HM FIXME: do we want another state char for raid0? It shows 'D' or 'A' now */
3047 rdev_for_each(rdev, mddev)
3048 DMEMIT(__raid_dev_status(rdev, array_in_sync));
3051 * In-sync/Reshape ratio:
3052 * The in-sync ratio shows the progress of:
3053 * - Initializing the raid set
3054 * - Rebuilding a subset of devices of the raid set
3055 * The user can distinguish between the two by referring
3056 * to the status characters.
3058 * The reshape ratio shows the progress of
3059 * changing the raid layout or the number of
3060 * disks of a raid set
3062 DMEMIT(" %llu/%llu", (unsigned long long) progress,
3063 (unsigned long long) resync_max_sectors);
3069 * See Documentation/device-mapper/dm-raid.txt for
3070 * information on each of these states.
3072 DMEMIT(" %s", sync_action);
3077 * resync_mismatches/mismatch_cnt
3078 * This field shows the number of discrepancies found when
3079 * performing a "check" of the raid set.
3081 DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3086 * data_offset (needed for out of space reshaping)
3087 * This field shows the data offset into the data
3088 * image LV where the first stripes data starts.
3090 * We keep data_offset equal on all raid disks of the set,
3091 * so retrieving it from the first raid disk is sufficient.
3093 DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
3096 case STATUSTYPE_TABLE:
3097 /* Report the table line string you would use to construct this raid set */
3099 /* Calculate raid parameter count */
3100 rdev_for_each(rdev, mddev)
3101 if (test_bit(WriteMostly, &rdev->flags))
3102 write_mostly_params += 2;
3103 raid_param_cnt += memweight(rs->rebuild_disks,
3104 DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks)) * 2 +
3105 write_mostly_params +
3106 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3107 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
3108 /* Emit table line */
3109 DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3110 if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3111 DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3112 raid10_md_layout_to_format(mddev->layout));
3113 if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3114 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3115 raid10_md_layout_to_copies(mddev->layout));
3116 if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3117 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3118 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3119 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
3120 if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3121 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3122 (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3123 if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3124 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3125 (unsigned long long) rs->data_offset);
3126 if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3127 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3128 mddev->bitmap_info.daemon_sleep);
3129 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3130 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3131 mddev->delta_disks);
3132 if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3133 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3135 rdev_for_each(rdev, mddev)
3136 if (test_bit(rdev->raid_disk, (void *) rs->rebuild_disks))
3137 DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD),
3139 rdev_for_each(rdev, mddev)
3140 if (test_bit(WriteMostly, &rdev->flags))
3141 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3143 if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3144 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3145 mddev->bitmap_info.max_write_behind);
3146 if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3147 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3148 mddev->sync_speed_max);
3149 if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3150 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3151 mddev->sync_speed_min);
3152 DMEMIT(" %d", rs->raid_disks);
3153 rdev_for_each(rdev, mddev) {
3154 struct raid_dev *rd = container_of(rdev, struct raid_dev, rdev);
3156 DMEMIT(" %s %s", __get_dev_name(rd->meta_dev),
3157 __get_dev_name(rd->data_dev));
3162 static int raid_message(struct dm_target *ti, unsigned argc, char **argv)
3164 struct raid_set *rs = ti->private;
3165 struct mddev *mddev = &rs->md;
3167 if (!mddev->pers || !mddev->pers->sync_request)
3170 if (!strcasecmp(argv[0], "frozen"))
3171 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3173 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3175 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
3176 if (mddev->sync_thread) {
3177 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3178 md_reap_sync_thread(mddev);
3180 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3181 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
3183 else if (!strcasecmp(argv[0], "resync"))
3184 ; /* MD_RECOVERY_NEEDED set below */
3185 else if (!strcasecmp(argv[0], "recover"))
3186 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3188 if (!strcasecmp(argv[0], "check"))
3189 set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3190 else if (!!strcasecmp(argv[0], "repair"))
3192 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3193 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3195 if (mddev->ro == 2) {
3196 /* A write to sync_action is enough to justify
3197 * canceling read-auto mode
3200 if (!mddev->suspended && mddev->sync_thread)
3201 md_wakeup_thread(mddev->sync_thread);
3203 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3204 if (!mddev->suspended && mddev->thread)
3205 md_wakeup_thread(mddev->thread);
3210 static int raid_iterate_devices(struct dm_target *ti,
3211 iterate_devices_callout_fn fn, void *data)
3213 struct raid_set *rs = ti->private;
3217 for (i = 0; !r && i < rs->md.raid_disks; i++)
3218 if (rs->dev[i].data_dev)
3220 rs->dev[i].data_dev,
3221 0, /* No offset on data devs */
3228 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3230 struct raid_set *rs = ti->private;
3231 unsigned chunk_size = rs->md.chunk_sectors << 9;
3232 struct r5conf *conf = rs->md.private;
3234 blk_limits_io_min(limits, chunk_size);
3235 blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded));
3238 static void raid_presuspend(struct dm_target *ti)
3240 struct raid_set *rs = ti->private;
3242 md_stop_writes(&rs->md);
3245 static void raid_postsuspend(struct dm_target *ti)
3247 struct raid_set *rs = ti->private;
3249 if (test_and_clear_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
3250 if (!rs->md.suspended)
3251 mddev_suspend(&rs->md);
3256 static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3259 uint64_t failed_devices, cleared_failed_devices = 0;
3260 unsigned long flags;
3261 struct dm_raid_superblock *sb;
3264 for (i = 0; i < rs->md.raid_disks; i++) {
3265 r = &rs->dev[i].rdev;
3266 if (test_bit(Faulty, &r->flags) && r->sb_page &&
3267 sync_page_io(r, 0, r->sb_size, r->sb_page,
3268 REQ_OP_READ, 0, true)) {
3269 DMINFO("Faulty %s device #%d has readable super block."
3270 " Attempting to revive it.",
3271 rs->raid_type->name, i);
3274 * Faulty bit may be set, but sometimes the array can
3275 * be suspended before the personalities can respond
3276 * by removing the device from the array (i.e. calling
3277 * 'hot_remove_disk'). If they haven't yet removed
3278 * the failed device, its 'raid_disk' number will be
3279 * '>= 0' - meaning we must call this function
3282 if ((r->raid_disk >= 0) &&
3283 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0))
3284 /* Failed to revive this device, try next */
3288 r->saved_raid_disk = i;
3290 clear_bit(Faulty, &r->flags);
3291 clear_bit(WriteErrorSeen, &r->flags);
3292 clear_bit(In_sync, &r->flags);
3293 if (r->mddev->pers->hot_add_disk(r->mddev, r)) {
3295 r->saved_raid_disk = -1;
3298 r->recovery_offset = 0;
3299 cleared_failed_devices |= 1 << i;
3303 if (cleared_failed_devices) {
3304 rdev_for_each(r, &rs->md) {
3305 sb = page_address(r->sb_page);
3306 failed_devices = le64_to_cpu(sb->failed_devices);
3307 failed_devices &= ~cleared_failed_devices;
3308 sb->failed_devices = cpu_to_le64(failed_devices);
3313 static int __load_dirty_region_bitmap(struct raid_set *rs)
3317 /* Try loading the bitmap unless "raid0", which does not have one */
3318 if (!rs_is_raid0(rs) &&
3319 !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
3320 r = bitmap_load(&rs->md);
3322 DMERR("Failed to load bitmap");
3328 /* Enforce updating all superblocks */
3329 static void rs_update_sbs(struct raid_set *rs)
3331 struct mddev *mddev = &rs->md;
3334 set_bit(MD_CHANGE_DEVS, &mddev->flags);
3336 md_update_sb(mddev, 1);
3341 * Reshape changes raid algorithm of @rs to new one within personality
3342 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3343 * disks from a raid set thus growing/shrinking it or resizes the set
3345 * Call mddev_lock_nointr() before!
3347 static int rs_start_reshape(struct raid_set *rs)
3350 struct mddev *mddev = &rs->md;
3351 struct md_personality *pers = mddev->pers;
3353 r = rs_setup_reshape(rs);
3357 /* Need to be resumed to be able to start reshape, recovery is frozen until raid_resume() though */
3358 if (mddev->suspended)
3359 mddev_resume(mddev);
3362 * Check any reshape constraints enforced by the personalility
3364 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3366 r = pers->check_reshape(mddev);
3368 rs->ti->error = "pers->check_reshape() failed";
3373 * Personality may not provide start reshape method in which
3374 * case check_reshape above has already covered everything
3376 if (pers->start_reshape) {
3377 r = pers->start_reshape(mddev);
3379 rs->ti->error = "pers->start_reshape() failed";
3384 /* Suspend because a resume will happen in raid_resume() */
3385 if (!mddev->suspended)
3386 mddev_suspend(mddev);
3389 * Now reshape got set up, update superblocks to
3390 * reflect the fact so that a table reload will
3391 * access proper superblock content in the ctr.
3398 static int raid_preresume(struct dm_target *ti)
3401 struct raid_set *rs = ti->private;
3402 struct mddev *mddev = &rs->md;
3404 /* This is a resume after a suspend of the set -> it's already started */
3405 if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
3409 * The superblocks need to be updated on disk if the
3410 * array is new or new devices got added (thus zeroed
3411 * out by userspace) or __load_dirty_region_bitmap
3412 * will overwrite them in core with old data or fail.
3414 if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
3418 * Disable/enable discard support on raid set after any
3419 * conversion, because devices can have been added
3421 configure_discard_support(rs);
3423 /* Load the bitmap from disk unless raid0 */
3424 r = __load_dirty_region_bitmap(rs);
3428 /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */
3429 if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) &&
3430 mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) {
3431 r = bitmap_resize(mddev->bitmap, mddev->dev_sectors,
3432 to_bytes(rs->requested_bitmap_chunk_sectors), 0);
3434 DMERR("Failed to resize bitmap");
3437 /* Check for any resize/reshape on @rs and adjust/initiate */
3438 /* Be prepared for mddev_resume() in raid_resume() */
3439 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3440 if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
3441 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3442 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3443 mddev->resync_min = mddev->recovery_cp;
3446 rs_set_capacity(rs);
3448 /* Check for any reshape request and region size change unless new raid set */
3449 if (test_and_clear_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3450 /* Initiate a reshape. */
3451 mddev_lock_nointr(mddev);
3452 r = rs_start_reshape(rs);
3453 mddev_unlock(mddev);
3455 DMWARN("Failed to check/start reshape, continuing without change");
3462 static void raid_resume(struct dm_target *ti)
3464 struct raid_set *rs = ti->private;
3465 struct mddev *mddev = &rs->md;
3467 if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
3469 * A secondary resume while the device is active.
3470 * Take this opportunity to check whether any failed
3471 * devices are reachable again.
3473 attempt_restore_of_faulty_devices(rs);
3479 * When passing in flags to the ctr, we expect userspace
3480 * to reset them because they made it to the superblocks
3481 * and reload the mapping anyway.
3483 * -> only unfreeze recovery in case of a table reload or
3484 * we'll have a bogus recovery/reshape position
3485 * retrieved from the superblock by the ctr because
3486 * the ongoing recovery/reshape will change it after read.
3488 if (!test_bit(RT_FLAG_KEEP_RS_FROZEN, &rs->runtime_flags))
3489 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3491 if (mddev->suspended)
3492 mddev_resume(mddev);
3496 static struct target_type raid_target = {
3498 .version = {1, 9, 0},
3499 .module = THIS_MODULE,
3503 .status = raid_status,
3504 .message = raid_message,
3505 .iterate_devices = raid_iterate_devices,
3506 .io_hints = raid_io_hints,
3507 .presuspend = raid_presuspend,
3508 .postsuspend = raid_postsuspend,
3509 .preresume = raid_preresume,
3510 .resume = raid_resume,
3513 static int __init dm_raid_init(void)
3515 DMINFO("Loading target version %u.%u.%u",
3516 raid_target.version[0],
3517 raid_target.version[1],
3518 raid_target.version[2]);
3519 return dm_register_target(&raid_target);
3522 static void __exit dm_raid_exit(void)
3524 dm_unregister_target(&raid_target);
3527 module_init(dm_raid_init);
3528 module_exit(dm_raid_exit);
3530 module_param(devices_handle_discard_safely, bool, 0644);
3531 MODULE_PARM_DESC(devices_handle_discard_safely,
3532 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
3534 MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
3535 MODULE_ALIAS("dm-raid0");
3536 MODULE_ALIAS("dm-raid1");
3537 MODULE_ALIAS("dm-raid10");
3538 MODULE_ALIAS("dm-raid4");
3539 MODULE_ALIAS("dm-raid5");
3540 MODULE_ALIAS("dm-raid6");
3541 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
3542 MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
3543 MODULE_LICENSE("GPL");