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
193 /* Array elements of 64 bit needed for rebuild/write_mostly bits */
194 #define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
197 * raid set level, layout and chunk sectors backup/restore
202 int new_chunk_sectors;
206 struct dm_target *ti;
208 uint32_t bitmap_loaded;
209 unsigned long ctr_flags;
210 unsigned long runtime_flags;
212 uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
220 struct raid_type *raid_type;
221 struct dm_target_callbacks callbacks;
222 struct rs_layout rs_layout;
224 struct raid_dev dev[0];
227 static void rs_config_backup(struct raid_set *rs)
229 struct mddev *mddev = &rs->md;
230 struct rs_layout *l = &rs->rs_layout;
232 l->new_level = mddev->new_level;
233 l->new_layout = mddev->new_layout;
234 l->new_chunk_sectors = mddev->new_chunk_sectors;
237 static void rs_config_restore(struct raid_set *rs)
239 struct mddev *mddev = &rs->md;
240 struct rs_layout *l = &rs->rs_layout;
242 mddev->new_level = l->new_level;
243 mddev->new_layout = l->new_layout;
244 mddev->new_chunk_sectors = l->new_chunk_sectors;
247 /* raid10 algorithms (i.e. formats) */
248 #define ALGORITHM_RAID10_DEFAULT 0
249 #define ALGORITHM_RAID10_NEAR 1
250 #define ALGORITHM_RAID10_OFFSET 2
251 #define ALGORITHM_RAID10_FAR 3
253 /* Supported raid types and properties. */
254 static struct raid_type {
255 const char *name; /* RAID algorithm. */
256 const char *descr; /* Descriptor text for logging. */
257 const unsigned parity_devs; /* # of parity devices. */
258 const unsigned minimal_devs; /* minimal # of devices in set. */
259 const unsigned level; /* RAID level. */
260 const unsigned algorithm; /* RAID algorithm. */
262 {"raid0", "raid0 (striping)", 0, 2, 0, 0 /* NONE */},
263 {"raid1", "raid1 (mirroring)", 0, 2, 1, 0 /* NONE */},
264 {"raid10_far", "raid10 far (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_FAR},
265 {"raid10_offset", "raid10 offset (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_OFFSET},
266 {"raid10_near", "raid10 near (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_NEAR},
267 {"raid10", "raid10 (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_DEFAULT},
268 {"raid4", "raid4 (dedicated last parity disk)", 1, 2, 4, ALGORITHM_PARITY_N}, /* raid4 layout = raid5_n */
269 {"raid5_n", "raid5 (dedicated last parity disk)", 1, 2, 5, ALGORITHM_PARITY_N},
270 {"raid5_ls", "raid5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC},
271 {"raid5_rs", "raid5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC},
272 {"raid5_la", "raid5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC},
273 {"raid5_ra", "raid5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC},
274 {"raid6_zr", "raid6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART},
275 {"raid6_nr", "raid6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART},
276 {"raid6_nc", "raid6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE},
277 {"raid6_n_6", "raid6 (dedicated parity/Q n/6)", 2, 4, 6, ALGORITHM_PARITY_N_6},
278 {"raid6_ls_6", "raid6 (left symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_SYMMETRIC_6},
279 {"raid6_rs_6", "raid6 (right symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_SYMMETRIC_6},
280 {"raid6_la_6", "raid6 (left asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_ASYMMETRIC_6},
281 {"raid6_ra_6", "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_ASYMMETRIC_6}
284 /* True, if @v is in inclusive range [@min, @max] */
285 static bool __within_range(long v, long min, long max)
287 return v >= min && v <= max;
290 /* All table line arguments are defined here */
291 static struct arg_name_flag {
292 const unsigned long flag;
294 } __arg_name_flags[] = {
295 { CTR_FLAG_SYNC, "sync"},
296 { CTR_FLAG_NOSYNC, "nosync"},
297 { CTR_FLAG_REBUILD, "rebuild"},
298 { CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
299 { CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
300 { CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
301 { CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
302 { CTR_FLAG_WRITE_MOSTLY, "writemostly"},
303 { CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
304 { CTR_FLAG_REGION_SIZE, "region_size"},
305 { CTR_FLAG_RAID10_COPIES, "raid10_copies"},
306 { CTR_FLAG_RAID10_FORMAT, "raid10_format"},
307 { CTR_FLAG_DATA_OFFSET, "data_offset"},
308 { CTR_FLAG_DELTA_DISKS, "delta_disks"},
309 { CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
312 /* Return argument name string for given @flag */
313 static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
315 if (hweight32(flag) == 1) {
316 struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
318 while (anf-- > __arg_name_flags)
319 if (flag & anf->flag)
323 DMERR("%s called with more than one flag!", __func__);
329 * bool helpers to test for various raid levels of a raid set,
330 * is. it's level as reported by the superblock rather than
331 * the requested raid_type passed to the constructor.
333 /* Return true, if raid set in @rs is raid0 */
334 static bool rs_is_raid0(struct raid_set *rs)
336 return !rs->md.level;
339 /* Return true, if raid set in @rs is raid10 */
340 static bool rs_is_raid10(struct raid_set *rs)
342 return rs->md.level == 10;
345 /* Return true, if raid set in @rs is level 4, 5 or 6 */
346 static bool rs_is_raid456(struct raid_set *rs)
348 return __within_range(rs->md.level, 4, 6);
351 /* Return true, if raid set in @rs is reshapable */
352 static unsigned int __is_raid10_far(int layout);
353 static bool rs_is_reshapable(struct raid_set *rs)
355 return rs_is_raid456(rs) ||
356 (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
360 * bool helpers to test for various raid levels of a raid type
363 /* Return true, if raid type in @rt is raid0 */
364 static bool rt_is_raid0(struct raid_type *rt)
369 /* Return true, if raid type in @rt is raid1 */
370 static bool rt_is_raid1(struct raid_type *rt)
372 return rt->level == 1;
375 /* Return true, if raid type in @rt is raid10 */
376 static bool rt_is_raid10(struct raid_type *rt)
378 return rt->level == 10;
381 /* Return true, if raid type in @rt is raid4/5 */
382 static bool rt_is_raid45(struct raid_type *rt)
384 return __within_range(rt->level, 4, 5);
387 /* Return true, if raid type in @rt is raid6 */
388 static bool rt_is_raid6(struct raid_type *rt)
390 return rt->level == 6;
393 /* Return true, if raid type in @rt is raid4/5/6 */
394 static bool rt_is_raid456(struct raid_type *rt)
396 return __within_range(rt->level, 4, 6);
398 /* END: raid level bools */
400 /* Return valid ctr flags for the raid level of @rs */
401 static unsigned long __valid_flags(struct raid_set *rs)
403 if (rt_is_raid0(rs->raid_type))
404 return RAID0_VALID_FLAGS;
405 else if (rt_is_raid1(rs->raid_type))
406 return RAID1_VALID_FLAGS;
407 else if (rt_is_raid10(rs->raid_type))
408 return RAID10_VALID_FLAGS;
409 else if (rt_is_raid45(rs->raid_type))
410 return RAID45_VALID_FLAGS;
411 else if (rt_is_raid6(rs->raid_type))
412 return RAID6_VALID_FLAGS;
418 * Check for valid flags set on @rs
420 * Has to be called after parsing of the ctr flags!
422 static int rs_check_for_valid_flags(struct raid_set *rs)
424 if (rs->ctr_flags & ~__valid_flags(rs)) {
425 rs->ti->error = "Invalid flags combination";
432 /* MD raid10 bit definitions and helpers */
433 #define RAID10_OFFSET (1 << 16) /* stripes with data copies area adjacent on devices */
434 #define RAID10_BROCKEN_USE_FAR_SETS (1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
435 #define RAID10_USE_FAR_SETS (1 << 18) /* Use sets instead of whole stripe rotation */
436 #define RAID10_FAR_COPIES_SHIFT 8 /* raid10 # far copies shift (2nd byte of layout) */
438 /* Return md raid10 near copies for @layout */
439 static unsigned int __raid10_near_copies(int layout)
441 return layout & 0xFF;
444 /* Return md raid10 far copies for @layout */
445 static unsigned int __raid10_far_copies(int layout)
447 return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
450 /* Return true if md raid10 offset for @layout */
451 static unsigned int __is_raid10_offset(int layout)
453 return layout & RAID10_OFFSET;
456 /* Return true if md raid10 near for @layout */
457 static unsigned int __is_raid10_near(int layout)
459 return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
462 /* Return true if md raid10 far for @layout */
463 static unsigned int __is_raid10_far(int layout)
465 return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
468 /* Return md raid10 layout string for @layout */
469 static const char *raid10_md_layout_to_format(int layout)
472 * Bit 16 stands for "offset"
473 * (i.e. adjacent stripes hold copies)
475 * Refer to MD's raid10.c for details
477 if (__is_raid10_offset(layout))
480 if (__raid10_near_copies(layout) > 1)
483 WARN_ON(__raid10_far_copies(layout) < 2);
488 /* Return md raid10 algorithm for @name */
489 static const int raid10_name_to_format(const char *name)
491 if (!strcasecmp(name, "near"))
492 return ALGORITHM_RAID10_NEAR;
493 else if (!strcasecmp(name, "offset"))
494 return ALGORITHM_RAID10_OFFSET;
495 else if (!strcasecmp(name, "far"))
496 return ALGORITHM_RAID10_FAR;
501 /* Return md raid10 copies for @layout */
502 static unsigned int raid10_md_layout_to_copies(int layout)
504 return __raid10_near_copies(layout) > 1 ?
505 __raid10_near_copies(layout) : __raid10_far_copies(layout);
508 /* Return md raid10 format id for @format string */
509 static int raid10_format_to_md_layout(struct raid_set *rs,
510 unsigned int algorithm,
513 unsigned int n = 1, f = 1, r = 0;
516 * MD resilienece flaw:
518 * enabling use_far_sets for far/offset formats causes copies
519 * to be colocated on the same devs together with their origins!
521 * -> disable it for now in the definition above
523 if (algorithm == ALGORITHM_RAID10_DEFAULT ||
524 algorithm == ALGORITHM_RAID10_NEAR)
527 else if (algorithm == ALGORITHM_RAID10_OFFSET) {
530 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
531 r |= RAID10_USE_FAR_SETS;
533 } else if (algorithm == ALGORITHM_RAID10_FAR) {
536 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
537 r |= RAID10_USE_FAR_SETS;
542 return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
544 /* END: MD raid10 bit definitions and helpers */
546 /* Check for any of the raid10 algorithms */
547 static int __got_raid10(struct raid_type *rtp, const int layout)
549 if (rtp->level == 10) {
550 switch (rtp->algorithm) {
551 case ALGORITHM_RAID10_DEFAULT:
552 case ALGORITHM_RAID10_NEAR:
553 return __is_raid10_near(layout);
554 case ALGORITHM_RAID10_OFFSET:
555 return __is_raid10_offset(layout);
556 case ALGORITHM_RAID10_FAR:
557 return __is_raid10_far(layout);
566 /* Return raid_type for @name */
567 static struct raid_type *get_raid_type(const char *name)
569 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
571 while (rtp-- > raid_types)
572 if (!strcasecmp(rtp->name, name))
578 /* Return raid_type for @name based derived from @level and @layout */
579 static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
581 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
583 while (rtp-- > raid_types) {
584 /* RAID10 special checks based on @layout flags/properties */
585 if (rtp->level == level &&
586 (__got_raid10(rtp, layout) || rtp->algorithm == layout))
594 * Set the mddev properties in @rs to the current
595 * ones retrieved from the freshest superblock
597 static void rs_set_cur(struct raid_set *rs)
599 struct mddev *mddev = &rs->md;
601 mddev->new_level = mddev->level;
602 mddev->new_layout = mddev->layout;
603 mddev->new_chunk_sectors = mddev->chunk_sectors;
607 * Set the mddev properties in @rs to the new
608 * ones requested by the ctr
610 static void rs_set_new(struct raid_set *rs)
612 struct mddev *mddev = &rs->md;
614 mddev->level = mddev->new_level;
615 mddev->layout = mddev->new_layout;
616 mddev->chunk_sectors = mddev->new_chunk_sectors;
617 mddev->raid_disks = rs->raid_disks;
618 mddev->delta_disks = 0;
621 static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
627 if (raid_devs <= raid_type->parity_devs) {
628 ti->error = "Insufficient number of devices";
629 return ERR_PTR(-EINVAL);
632 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL);
634 ti->error = "Cannot allocate raid context";
635 return ERR_PTR(-ENOMEM);
640 rs->raid_disks = raid_devs;
644 rs->raid_type = raid_type;
645 rs->md.raid_disks = raid_devs;
646 rs->md.level = raid_type->level;
647 rs->md.new_level = rs->md.level;
648 rs->md.layout = raid_type->algorithm;
649 rs->md.new_layout = rs->md.layout;
650 rs->md.delta_disks = 0;
651 rs->md.recovery_cp = rs_is_raid0(rs) ? MaxSector : 0;
653 for (i = 0; i < raid_devs; i++)
654 md_rdev_init(&rs->dev[i].rdev);
657 * Remaining items to be initialized by further RAID params:
660 * rs->md.chunk_sectors
661 * rs->md.new_chunk_sectors
668 static void raid_set_free(struct raid_set *rs)
672 for (i = 0; i < rs->md.raid_disks; i++) {
673 if (rs->dev[i].meta_dev)
674 dm_put_device(rs->ti, rs->dev[i].meta_dev);
675 md_rdev_clear(&rs->dev[i].rdev);
676 if (rs->dev[i].data_dev)
677 dm_put_device(rs->ti, rs->dev[i].data_dev);
684 * For every device we have two words
685 * <meta_dev>: meta device name or '-' if missing
686 * <data_dev>: data device name or '-' if missing
688 * The following are permitted:
691 * <meta_dev> <data_dev>
693 * The following is not allowed:
696 * This code parses those words. If there is a failure,
697 * the caller must use raid_set_free() to unwind the operations.
699 static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
703 int metadata_available = 0;
707 /* Put off the number of raid devices argument to get to dev pairs */
708 arg = dm_shift_arg(as);
712 for (i = 0; i < rs->md.raid_disks; i++) {
713 rs->dev[i].rdev.raid_disk = i;
715 rs->dev[i].meta_dev = NULL;
716 rs->dev[i].data_dev = NULL;
719 * There are no offsets, since there is a separate device
720 * for data and metadata.
722 rs->dev[i].rdev.data_offset = 0;
723 rs->dev[i].rdev.mddev = &rs->md;
725 arg = dm_shift_arg(as);
729 if (strcmp(arg, "-")) {
730 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
731 &rs->dev[i].meta_dev);
733 rs->ti->error = "RAID metadata device lookup failure";
737 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
738 if (!rs->dev[i].rdev.sb_page) {
739 rs->ti->error = "Failed to allocate superblock page";
744 arg = dm_shift_arg(as);
748 if (!strcmp(arg, "-")) {
749 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
750 (!rs->dev[i].rdev.recovery_offset)) {
751 rs->ti->error = "Drive designated for rebuild not specified";
755 if (rs->dev[i].meta_dev) {
756 rs->ti->error = "No data device supplied with metadata device";
763 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
764 &rs->dev[i].data_dev);
766 rs->ti->error = "RAID device lookup failure";
770 if (rs->dev[i].meta_dev) {
771 metadata_available = 1;
772 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
774 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
775 list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
776 if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
780 if (metadata_available) {
782 rs->md.persistent = 1;
783 rs->md.major_version = 2;
784 } else if (rebuild && !rs->md.recovery_cp) {
786 * Without metadata, we will not be able to tell if the array
787 * is in-sync or not - we must assume it is not. Therefore,
788 * it is impossible to rebuild a drive.
790 * Even if there is metadata, the on-disk information may
791 * indicate that the array is not in-sync and it will then
794 * User could specify 'nosync' option if desperate.
796 rs->ti->error = "Unable to rebuild drive while array is not in-sync";
804 * validate_region_size
806 * @region_size: region size in sectors. If 0, pick a size (4MiB default).
808 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
809 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
811 * Returns: 0 on success, -EINVAL on failure.
813 static int validate_region_size(struct raid_set *rs, unsigned long region_size)
815 unsigned long min_region_size = rs->ti->len / (1 << 21);
819 * Choose a reasonable default. All figures in sectors.
821 if (min_region_size > (1 << 13)) {
822 /* If not a power of 2, make it the next power of 2 */
823 region_size = roundup_pow_of_two(min_region_size);
824 DMINFO("Choosing default region size of %lu sectors",
827 DMINFO("Choosing default region size of 4MiB");
828 region_size = 1 << 13; /* sectors */
832 * Validate user-supplied value.
834 if (region_size > rs->ti->len) {
835 rs->ti->error = "Supplied region size is too large";
839 if (region_size < min_region_size) {
840 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
841 region_size, min_region_size);
842 rs->ti->error = "Supplied region size is too small";
846 if (!is_power_of_2(region_size)) {
847 rs->ti->error = "Region size is not a power of 2";
851 if (region_size < rs->md.chunk_sectors) {
852 rs->ti->error = "Region size is smaller than the chunk size";
858 * Convert sectors to bytes.
860 rs->md.bitmap_info.chunksize = (region_size << 9);
866 * validate_raid_redundancy
869 * Determine if there are enough devices in the array that haven't
870 * failed (or are being rebuilt) to form a usable array.
872 * Returns: 0 on success, -EINVAL on failure.
874 static int validate_raid_redundancy(struct raid_set *rs)
876 unsigned i, rebuild_cnt = 0;
877 unsigned rebuilds_per_group = 0, copies, d;
878 unsigned group_size, last_group_start;
880 for (i = 0; i < rs->md.raid_disks; i++)
881 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
882 !rs->dev[i].rdev.sb_page)
885 switch (rs->raid_type->level) {
887 if (rebuild_cnt >= rs->md.raid_disks)
893 if (rebuild_cnt > rs->raid_type->parity_devs)
897 copies = raid10_md_layout_to_copies(rs->md.layout);
898 if (rebuild_cnt < copies)
902 * It is possible to have a higher rebuild count for RAID10,
903 * as long as the failed devices occur in different mirror
904 * groups (i.e. different stripes).
906 * When checking "near" format, make sure no adjacent devices
907 * have failed beyond what can be handled. In addition to the
908 * simple case where the number of devices is a multiple of the
909 * number of copies, we must also handle cases where the number
910 * of devices is not a multiple of the number of copies.
911 * E.g. dev1 dev2 dev3 dev4 dev5
915 if (!strcmp("near", raid10_md_layout_to_format(rs->md.layout))) {
916 for (i = 0; i < rs->md.raid_disks * copies; i++) {
918 rebuilds_per_group = 0;
919 d = i % rs->md.raid_disks;
920 if ((!rs->dev[d].rdev.sb_page ||
921 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
922 (++rebuilds_per_group >= copies))
929 * When checking "far" and "offset" formats, we need to ensure
930 * that the device that holds its copy is not also dead or
931 * being rebuilt. (Note that "far" and "offset" formats only
932 * support two copies right now. These formats also only ever
933 * use the 'use_far_sets' variant.)
935 * This check is somewhat complicated by the need to account
936 * for arrays that are not a multiple of (far) copies. This
937 * results in the need to treat the last (potentially larger)
940 group_size = (rs->md.raid_disks / copies);
941 last_group_start = (rs->md.raid_disks / group_size) - 1;
942 last_group_start *= group_size;
943 for (i = 0; i < rs->md.raid_disks; i++) {
944 if (!(i % copies) && !(i > last_group_start))
945 rebuilds_per_group = 0;
946 if ((!rs->dev[i].rdev.sb_page ||
947 !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
948 (++rebuilds_per_group >= copies))
964 * Possible arguments are...
965 * <chunk_size> [optional_args]
967 * Argument definitions
968 * <chunk_size> The number of sectors per disk that
969 * will form the "stripe"
970 * [[no]sync] Force or prevent recovery of the
972 * [rebuild <idx>] Rebuild the drive indicated by the index
973 * [daemon_sleep <ms>] Time between bitmap daemon work to
975 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
976 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
977 * [write_mostly <idx>] Indicate a write mostly drive via index
978 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
979 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs
980 * [region_size <sectors>] Defines granularity of bitmap
982 * RAID10-only options:
983 * [raid10_copies <# copies>] Number of copies. (Default: 2)
984 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
986 static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
987 unsigned num_raid_params)
989 int raid10_format = ALGORITHM_RAID10_DEFAULT;
990 unsigned raid10_copies = 2;
992 unsigned value, region_size = 0;
994 const char *arg, *key;
996 struct raid_type *rt = rs->raid_type;
998 arg = dm_shift_arg(as);
999 num_raid_params--; /* Account for chunk_size argument */
1001 if (kstrtouint(arg, 10, &value) < 0) {
1002 rs->ti->error = "Bad numerical argument given for chunk_size";
1007 * First, parse the in-order required arguments
1008 * "chunk_size" is the only argument of this type.
1010 if (rt_is_raid1(rt)) {
1012 DMERR("Ignoring chunk size parameter for RAID 1");
1014 } else if (!is_power_of_2(value)) {
1015 rs->ti->error = "Chunk size must be a power of 2";
1017 } else if (value < 8) {
1018 rs->ti->error = "Chunk size value is too small";
1022 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1025 * We set each individual device as In_sync with a completed
1026 * 'recovery_offset'. If there has been a device failure or
1027 * replacement then one of the following cases applies:
1029 * 1) User specifies 'rebuild'.
1030 * - Device is reset when param is read.
1031 * 2) A new device is supplied.
1032 * - No matching superblock found, resets device.
1033 * 3) Device failure was transient and returns on reload.
1034 * - Failure noticed, resets device for bitmap replay.
1035 * 4) Device hadn't completed recovery after previous failure.
1036 * - Superblock is read and overrides recovery_offset.
1038 * What is found in the superblocks of the devices is always
1039 * authoritative, unless 'rebuild' or '[no]sync' was specified.
1041 for (i = 0; i < rs->md.raid_disks; i++) {
1042 set_bit(In_sync, &rs->dev[i].rdev.flags);
1043 rs->dev[i].rdev.recovery_offset = MaxSector;
1047 * Second, parse the unordered optional arguments
1049 for (i = 0; i < num_raid_params; i++) {
1050 key = dm_shift_arg(as);
1052 rs->ti->error = "Not enough raid parameters given";
1056 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1057 if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1058 rs->ti->error = "Only one 'nosync' argument allowed";
1061 rs->md.recovery_cp = MaxSector;
1064 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1065 if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1066 rs->ti->error = "Only one 'sync' argument allowed";
1069 rs->md.recovery_cp = 0;
1072 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1073 if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1074 rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1080 arg = dm_shift_arg(as);
1081 i++; /* Account for the argument pairs */
1083 rs->ti->error = "Wrong number of raid parameters given";
1088 * Parameters that take a string value are checked here.
1091 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1092 if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1093 rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1096 if (!rt_is_raid10(rt)) {
1097 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1100 raid10_format = raid10_name_to_format(arg);
1101 if (raid10_format < 0) {
1102 rs->ti->error = "Invalid 'raid10_format' value given";
1103 return raid10_format;
1108 if (kstrtouint(arg, 10, &value) < 0) {
1109 rs->ti->error = "Bad numerical argument given in raid params";
1113 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1115 * "rebuild" is being passed in by userspace to provide
1116 * indexes of replaced devices and to set up additional
1117 * devices on raid level takeover.
1119 if (!__within_range(value, 0, rs->raid_disks - 1)) {
1120 rs->ti->error = "Invalid rebuild index given";
1124 if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1125 rs->ti->error = "rebuild for this index already given";
1129 rd = rs->dev + value;
1130 clear_bit(In_sync, &rd->rdev.flags);
1131 clear_bit(Faulty, &rd->rdev.flags);
1132 rd->rdev.recovery_offset = 0;
1133 set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1134 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1135 if (!rt_is_raid1(rt)) {
1136 rs->ti->error = "write_mostly option is only valid for RAID1";
1140 if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1141 rs->ti->error = "Invalid write_mostly index given";
1145 set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1146 set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1147 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1148 if (!rt_is_raid1(rt)) {
1149 rs->ti->error = "max_write_behind option is only valid for RAID1";
1153 if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1154 rs->ti->error = "Only one max_write_behind argument pair allowed";
1159 * In device-mapper, we specify things in sectors, but
1160 * MD records this value in kB
1163 if (value > COUNTER_MAX) {
1164 rs->ti->error = "Max write-behind limit out of range";
1168 rs->md.bitmap_info.max_write_behind = value;
1169 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1170 if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1171 rs->ti->error = "Only one daemon_sleep argument pair allowed";
1174 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
1175 rs->ti->error = "daemon sleep period out of range";
1178 rs->md.bitmap_info.daemon_sleep = value;
1179 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1180 /* Userspace passes new data_offset after having extended the the data image LV */
1181 if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1182 rs->ti->error = "Only one data_offset argument pair allowed";
1185 /* Ensure sensible data offset */
1187 rs->ti->error = "Bogus data_offset value";
1190 rs->data_offset = value;
1191 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1192 /* Define the +/-# of disks to add to/remove from the given raid set */
1193 if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1194 rs->ti->error = "Only one delta_disks argument pair allowed";
1197 /* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1198 if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1199 rs->ti->error = "Too many delta_disk requested";
1203 rs->delta_disks = value;
1204 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1205 if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1206 rs->ti->error = "Only one stripe_cache argument pair allowed";
1211 * In device-mapper, we specify things in sectors, but
1212 * MD records this value in kB
1216 if (!rt_is_raid456(rt)) {
1217 rs->ti->error = "Inappropriate argument: stripe_cache";
1220 if (raid5_set_cache_size(&rs->md, (int)value)) {
1221 rs->ti->error = "Bad stripe_cache size";
1225 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1226 if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1227 rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1230 if (value > INT_MAX) {
1231 rs->ti->error = "min_recovery_rate out of range";
1234 rs->md.sync_speed_min = (int)value;
1235 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1236 if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1237 rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1240 if (value > INT_MAX) {
1241 rs->ti->error = "max_recovery_rate out of range";
1244 rs->md.sync_speed_max = (int)value;
1245 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1246 if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1247 rs->ti->error = "Only one region_size argument pair allowed";
1251 region_size = value;
1252 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1253 if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1254 rs->ti->error = "Only one raid10_copies argument pair allowed";
1258 if (!__within_range(value, 2, rs->md.raid_disks)) {
1259 rs->ti->error = "Bad value for 'raid10_copies'";
1263 raid10_copies = value;
1265 DMERR("Unable to parse RAID parameter: %s", key);
1266 rs->ti->error = "Unable to parse RAID parameter";
1271 if (validate_region_size(rs, region_size))
1274 if (rs->md.chunk_sectors)
1275 max_io_len = rs->md.chunk_sectors;
1277 max_io_len = region_size;
1279 if (dm_set_target_max_io_len(rs->ti, max_io_len))
1282 if (rt_is_raid10(rt)) {
1283 if (raid10_copies > rs->md.raid_disks) {
1284 rs->ti->error = "Not enough devices to satisfy specification";
1288 rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1289 if (rs->md.new_layout < 0) {
1290 rs->ti->error = "Error getting raid10 format";
1291 return rs->md.new_layout;
1294 rt = get_raid_type_by_ll(10, rs->md.new_layout);
1296 rs->ti->error = "Failed to recognize new raid10 layout";
1300 if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1301 rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1302 test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1303 rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1307 rs->md.layout = rs->md.new_layout;
1310 rs->raid10_copies = raid10_copies;
1312 /* Assume there are no metadata devices until the drives are parsed */
1313 rs->md.persistent = 0;
1314 rs->md.external = 1;
1316 /* Check, if any invalid ctr arguments have been passed in for the raid level */
1317 return rs_check_for_valid_flags(rs);
1320 /* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1321 static unsigned int mddev_data_stripes(struct raid_set *rs)
1323 return rs->md.raid_disks - rs->raid_type->parity_devs;
1326 /* Return # of data stripes of @rs (i.e. as of ctr) */
1327 static unsigned int rs_data_stripes(struct raid_set *rs)
1329 return rs->raid_disks - rs->raid_type->parity_devs;
1332 /* Calculate the sectors per device and per array used for @rs */
1333 static int rs_set_dev_and_array_sectors(struct raid_set *rs, bool use_mddev)
1336 unsigned int data_stripes;
1337 struct mddev *mddev = &rs->md;
1338 struct md_rdev *rdev;
1339 sector_t array_sectors = rs->ti->len, dev_sectors = rs->ti->len;
1342 delta_disks = mddev->delta_disks;
1343 data_stripes = mddev_data_stripes(rs);
1345 delta_disks = rs->delta_disks;
1346 data_stripes = rs_data_stripes(rs);
1349 /* Special raid1 case w/o delta_disks support (yet) */
1350 if (rt_is_raid1(rs->raid_type))
1352 else if (rt_is_raid10(rs->raid_type)) {
1353 if (rs->raid10_copies < 2 ||
1355 rs->ti->error = "Bogus raid10 data copies or delta disks";
1359 dev_sectors *= rs->raid10_copies;
1360 if (sector_div(dev_sectors, data_stripes))
1363 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1364 if (sector_div(array_sectors, rs->raid10_copies))
1367 } else if (sector_div(dev_sectors, data_stripes))
1371 /* Striped layouts */
1372 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1374 rdev_for_each(rdev, mddev)
1375 rdev->sectors = dev_sectors;
1377 mddev->array_sectors = array_sectors;
1378 mddev->dev_sectors = dev_sectors;
1382 rs->ti->error = "Target length not divisible by number of data devices";
1386 static void do_table_event(struct work_struct *ws)
1388 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1390 dm_table_event(rs->ti->table);
1393 static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
1395 struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
1397 return mddev_congested(&rs->md, bits);
1401 * Make sure a valid takover (level switch) is being requested on @rs
1403 * Conversions of raid sets from one MD personality to another
1404 * have to conform to restrictions which are enforced here.
1406 * Degration is already checked for in rs_check_conversion() below.
1408 static int rs_check_takeover(struct raid_set *rs)
1410 struct mddev *mddev = &rs->md;
1411 unsigned int near_copies;
1413 switch (mddev->level) {
1415 /* raid0 -> raid1/5 with one disk */
1416 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1417 mddev->raid_disks == 1)
1420 /* raid0 -> raid10 */
1421 if (mddev->new_level == 10 &&
1422 !(rs->raid_disks % 2))
1425 /* raid0 with multiple disks -> raid4/5/6 */
1426 if (__within_range(mddev->new_level, 4, 6) &&
1427 mddev->new_layout == ALGORITHM_PARITY_N &&
1428 mddev->raid_disks > 1)
1434 /* Can't takeover raid10_offset! */
1435 if (__is_raid10_offset(mddev->layout))
1438 near_copies = __raid10_near_copies(mddev->layout);
1440 /* raid10* -> raid0 */
1441 if (mddev->new_level == 0) {
1442 /* Can takeover raid10_near with raid disks divisable by data copies! */
1443 if (near_copies > 1 &&
1444 !(mddev->raid_disks % near_copies)) {
1445 mddev->raid_disks /= near_copies;
1446 mddev->delta_disks = mddev->raid_disks;
1450 /* Can takeover raid10_far */
1451 if (near_copies == 1 &&
1452 __raid10_far_copies(mddev->layout) > 1)
1458 /* raid10_{near,far} -> raid1 */
1459 if (mddev->new_level == 1 &&
1460 max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1463 /* raid10_{near,far} with 2 disks -> raid4/5 */
1464 if (__within_range(mddev->new_level, 4, 5) &&
1465 mddev->raid_disks == 2)
1470 /* raid1 with 2 disks -> raid4/5 */
1471 if (__within_range(mddev->new_level, 4, 5) &&
1472 mddev->raid_disks == 2) {
1473 mddev->degraded = 1;
1477 /* raid1 -> raid0 */
1478 if (mddev->new_level == 0 &&
1479 mddev->raid_disks == 1)
1482 /* raid1 -> raid10 */
1483 if (mddev->new_level == 10)
1489 /* raid4 -> raid0 */
1490 if (mddev->new_level == 0)
1493 /* raid4 -> raid1/5 with 2 disks */
1494 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1495 mddev->raid_disks == 2)
1498 /* raid4 -> raid5/6 with parity N */
1499 if (__within_range(mddev->new_level, 5, 6) &&
1500 mddev->layout == ALGORITHM_PARITY_N)
1505 /* raid5 with parity N -> raid0 */
1506 if (mddev->new_level == 0 &&
1507 mddev->layout == ALGORITHM_PARITY_N)
1510 /* raid5 with parity N -> raid4 */
1511 if (mddev->new_level == 4 &&
1512 mddev->layout == ALGORITHM_PARITY_N)
1515 /* raid5 with 2 disks -> raid1/4/10 */
1516 if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1517 mddev->raid_disks == 2)
1520 /* raid5 with parity N -> raid6 with parity N */
1521 if (mddev->new_level == 6 &&
1522 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1523 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1528 /* raid6 with parity N -> raid0 */
1529 if (mddev->new_level == 0 &&
1530 mddev->layout == ALGORITHM_PARITY_N)
1533 /* raid6 with parity N -> raid4 */
1534 if (mddev->new_level == 4 &&
1535 mddev->layout == ALGORITHM_PARITY_N)
1538 /* raid6_*_n with parity N -> raid5_* */
1539 if (mddev->new_level == 5 &&
1540 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1541 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1548 rs->ti->error = "takeover not possible";
1552 /* True if @rs requested to be taken over */
1553 static bool rs_takeover_requested(struct raid_set *rs)
1555 return rs->md.new_level != rs->md.level;
1558 /* True if @rs is requested to reshape by ctr */
1559 static bool rs_reshape_requested(struct raid_set *rs)
1561 struct mddev *mddev = &rs->md;
1566 return !__is_raid10_far(mddev->new_layout) &&
1567 mddev->new_level == mddev->level &&
1568 (mddev->new_layout != mddev->layout ||
1569 mddev->new_chunk_sectors != mddev->chunk_sectors ||
1570 rs->raid_disks + rs->delta_disks != mddev->raid_disks);
1574 #define FEATURE_FLAG_SUPPORTS_V190 0x1 /* Supports extended superblock */
1576 /* State flags for sb->flags */
1577 #define SB_FLAG_RESHAPE_ACTIVE 0x1
1578 #define SB_FLAG_RESHAPE_BACKWARDS 0x2
1581 * This structure is never routinely used by userspace, unlike md superblocks.
1582 * Devices with this superblock should only ever be accessed via device-mapper.
1584 #define DM_RAID_MAGIC 0x64526D44
1585 struct dm_raid_superblock {
1586 __le32 magic; /* "DmRd" */
1587 __le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1589 __le32 num_devices; /* Number of devices in this raid set. (Max 64) */
1590 __le32 array_position; /* The position of this drive in the raid set */
1592 __le64 events; /* Incremented by md when superblock updated */
1593 __le64 failed_devices; /* Pre 1.9.0 part of bit field of devices to */
1594 /* indicate failures (see extension below) */
1597 * This offset tracks the progress of the repair or replacement of
1598 * an individual drive.
1600 __le64 disk_recovery_offset;
1603 * This offset tracks the progress of the initial raid set
1604 * synchronisation/parity calculation.
1606 __le64 array_resync_offset;
1609 * raid characteristics
1613 __le32 stripe_sectors;
1615 /********************************************************************
1616 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1618 * FEATURE_FLAG_SUPPORTS_V190 in the features member indicates that those exist
1621 __le32 flags; /* Flags defining array states for reshaping */
1624 * This offset tracks the progress of a raid
1625 * set reshape in order to be able to restart it
1627 __le64 reshape_position;
1630 * These define the properties of the array in case of an interrupted reshape
1634 __le32 new_stripe_sectors;
1637 __le64 array_sectors; /* Array size in sectors */
1640 * Sector offsets to data on devices (reshaping).
1641 * Needed to support out of place reshaping, thus
1642 * not writing over any stripes whilst converting
1643 * them from old to new layout
1646 __le64 new_data_offset;
1648 __le64 sectors; /* Used device size in sectors */
1651 * Additonal Bit field of devices indicating failures to support
1652 * up to 256 devices with the 1.9.0 on-disk metadata format
1654 __le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
1656 __le32 incompat_features; /* Used to indicate any incompatible features */
1658 /* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
1661 static int read_disk_sb(struct md_rdev *rdev, int size)
1663 BUG_ON(!rdev->sb_page);
1665 if (rdev->sb_loaded)
1668 if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, 1)) {
1669 DMERR("Failed to read superblock of device at position %d",
1671 md_error(rdev->mddev, rdev);
1675 rdev->sb_loaded = 1;
1680 static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1682 failed_devices[0] = le64_to_cpu(sb->failed_devices);
1683 memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
1685 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
1686 int i = ARRAY_SIZE(sb->extended_failed_devices);
1689 failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
1693 static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
1695 int i = ARRAY_SIZE(sb->extended_failed_devices);
1697 sb->failed_devices = cpu_to_le64(failed_devices[0]);
1699 sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
1703 * Synchronize the superblock members with the raid set properties
1705 * All superblock data is little endian.
1707 static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
1709 bool update_failed_devices = false;
1711 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
1712 struct dm_raid_superblock *sb;
1713 struct raid_set *rs = container_of(mddev, struct raid_set, md);
1715 /* No metadata device, no superblock */
1716 if (!rdev->meta_bdev)
1719 BUG_ON(!rdev->sb_page);
1721 sb = page_address(rdev->sb_page);
1723 sb_retrieve_failed_devices(sb, failed_devices);
1725 for (i = 0; i < rs->raid_disks; i++)
1726 if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
1727 update_failed_devices = true;
1728 set_bit(i, (void *) failed_devices);
1731 if (update_failed_devices)
1732 sb_update_failed_devices(sb, failed_devices);
1734 sb->magic = cpu_to_le32(DM_RAID_MAGIC);
1735 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
1737 sb->num_devices = cpu_to_le32(mddev->raid_disks);
1738 sb->array_position = cpu_to_le32(rdev->raid_disk);
1740 sb->events = cpu_to_le64(mddev->events);
1742 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
1743 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
1745 sb->level = cpu_to_le32(mddev->level);
1746 sb->layout = cpu_to_le32(mddev->layout);
1747 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
1749 sb->new_level = cpu_to_le32(mddev->new_level);
1750 sb->new_layout = cpu_to_le32(mddev->new_layout);
1751 sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
1753 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1755 smp_rmb(); /* Make sure we access most recent reshape position */
1756 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1757 if (le64_to_cpu(sb->reshape_position) != MaxSector) {
1758 /* Flag ongoing reshape */
1759 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
1761 if (mddev->delta_disks < 0 || mddev->reshape_backwards)
1762 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
1764 /* Clear reshape flags */
1765 sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
1768 sb->array_sectors = cpu_to_le64(mddev->array_sectors);
1769 sb->data_offset = cpu_to_le64(rdev->data_offset);
1770 sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
1771 sb->sectors = cpu_to_le64(rdev->sectors);
1773 /* Zero out the rest of the payload after the size of the superblock */
1774 memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
1780 * This function creates a superblock if one is not found on the device
1781 * and will decide which superblock to use if there's a choice.
1783 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
1785 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
1788 struct dm_raid_superblock *sb;
1789 struct dm_raid_superblock *refsb;
1790 uint64_t events_sb, events_refsb;
1793 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
1794 if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) {
1795 DMERR("superblock size of a logical block is no longer valid");
1799 r = read_disk_sb(rdev, rdev->sb_size);
1803 sb = page_address(rdev->sb_page);
1806 * Two cases that we want to write new superblocks and rebuild:
1807 * 1) New device (no matching magic number)
1808 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
1810 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
1811 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
1812 super_sync(rdev->mddev, rdev);
1814 set_bit(FirstUse, &rdev->flags);
1815 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
1817 /* Force writing of superblocks to disk */
1818 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags);
1820 /* Any superblock is better than none, choose that if given */
1821 return refdev ? 0 : 1;
1827 events_sb = le64_to_cpu(sb->events);
1829 refsb = page_address(refdev->sb_page);
1830 events_refsb = le64_to_cpu(refsb->events);
1832 return (events_sb > events_refsb) ? 1 : 0;
1835 static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
1839 struct mddev *mddev = &rs->md;
1841 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
1842 struct dm_raid_superblock *sb;
1843 uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
1845 struct dm_raid_superblock *sb2;
1847 sb = page_address(rdev->sb_page);
1848 events_sb = le64_to_cpu(sb->events);
1851 * Initialise to 1 if this is a new superblock.
1853 mddev->events = events_sb ? : 1;
1855 mddev->reshape_position = MaxSector;
1858 * Reshaping is supported, e.g. reshape_position is valid
1859 * in superblock and superblock content is authoritative.
1861 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
1862 /* Superblock is authoritative wrt given raid set layout! */
1863 mddev->raid_disks = le32_to_cpu(sb->num_devices);
1864 mddev->level = le32_to_cpu(sb->level);
1865 mddev->layout = le32_to_cpu(sb->layout);
1866 mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
1867 mddev->new_level = le32_to_cpu(sb->new_level);
1868 mddev->new_layout = le32_to_cpu(sb->new_layout);
1869 mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
1870 mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1871 mddev->array_sectors = le64_to_cpu(sb->array_sectors);
1873 /* raid was reshaping and got interrupted */
1874 if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
1875 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1876 DMERR("Reshape requested but raid set is still reshaping");
1880 if (mddev->delta_disks < 0 ||
1881 (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
1882 mddev->reshape_backwards = 1;
1884 mddev->reshape_backwards = 0;
1886 mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1887 rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
1892 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
1894 if (le32_to_cpu(sb->level) != mddev->level) {
1895 DMERR("Reshaping/takeover raid sets not yet supported. (raid level/stripes/size change)");
1898 if (le32_to_cpu(sb->layout) != mddev->layout) {
1899 DMERR("Reshaping raid sets not yet supported. (raid layout change)");
1900 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout);
1901 DMERR(" Old layout: %s w/ %d copies",
1902 raid10_md_layout_to_format(le32_to_cpu(sb->layout)),
1903 raid10_md_layout_to_copies(le32_to_cpu(sb->layout)));
1904 DMERR(" New layout: %s w/ %d copies",
1905 raid10_md_layout_to_format(mddev->layout),
1906 raid10_md_layout_to_copies(mddev->layout));
1909 if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) {
1910 DMERR("Reshaping raid sets not yet supported. (stripe sectors change)");
1914 /* We can only change the number of devices in raid1 with old (i.e. pre 1.0.7) metadata */
1915 if (!rt_is_raid1(rs->raid_type) &&
1916 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) {
1917 DMERR("Reshaping raid sets not yet supported. (device count change from %u to %u)",
1918 sb->num_devices, mddev->raid_disks);
1922 /* Table line is checked vs. authoritative superblock */
1926 if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
1927 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
1930 * During load, we set FirstUse if a new superblock was written.
1931 * There are two reasons we might not have a superblock:
1932 * 1) The raid set is brand new - in which case, all of the
1933 * devices must have their In_sync bit set. Also,
1934 * recovery_cp must be 0, unless forced.
1935 * 2) This is a new device being added to an old raid set
1936 * and the new device needs to be rebuilt - in which
1937 * case the In_sync bit will /not/ be set and
1938 * recovery_cp must be MaxSector.
1941 rdev_for_each(r, mddev) {
1942 if (test_bit(FirstUse, &r->flags))
1945 if (!test_bit(In_sync, &r->flags)) {
1946 DMINFO("Device %d specified for rebuild; clearing superblock",
1950 if (test_bit(FirstUse, &r->flags))
1957 if (new_devs == rs->raid_disks || !rebuilds) {
1958 /* Replace a broken device */
1959 if (new_devs == 1 && !rs->delta_disks)
1961 if (new_devs == rs->raid_disks) {
1962 DMINFO("Superblocks created for new raid set");
1963 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
1964 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
1965 mddev->recovery_cp = 0;
1966 } else if (new_devs && new_devs != rs->raid_disks && !rebuilds) {
1967 DMERR("New device injected into existing raid set without "
1968 "'delta_disks' or 'rebuild' parameter specified");
1971 } else if (new_devs && new_devs != rebuilds) {
1972 DMERR("%u 'rebuild' devices cannot be injected into"
1973 " a raid set with %u other first-time devices",
1974 rebuilds, new_devs);
1976 } else if (rebuilds) {
1977 if (rebuild_and_new && rebuilds != rebuild_and_new) {
1978 DMERR("new device%s provided without 'rebuild'",
1979 new_devs > 1 ? "s" : "");
1981 } else if (mddev->recovery_cp != MaxSector) {
1982 DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
1983 (unsigned long long) mddev->recovery_cp);
1985 } else if (mddev->reshape_position != MaxSector) {
1986 DMERR("'rebuild' specified while raid set is being reshaped");
1992 * Now we set the Faulty bit for those devices that are
1993 * recorded in the superblock as failed.
1995 sb_retrieve_failed_devices(sb, failed_devices);
1996 rdev_for_each(r, mddev) {
1999 sb2 = page_address(r->sb_page);
2000 sb2->failed_devices = 0;
2001 memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2004 * Check for any device re-ordering.
2006 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2007 role = le32_to_cpu(sb2->array_position);
2011 if (role != r->raid_disk) {
2012 if (__is_raid10_near(mddev->layout)) {
2013 if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2014 rs->raid_disks % rs->raid10_copies) {
2016 "Cannot change raid10 near set to odd # of devices!";
2020 sb2->array_position = cpu_to_le32(r->raid_disk);
2022 } else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2023 !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2024 !rt_is_raid1(rs->raid_type)) {
2025 rs->ti->error = "Cannot change device positions in raid set";
2029 DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2033 * Partial recovery is performed on
2034 * returning failed devices.
2036 if (test_bit(role, (void *) failed_devices))
2037 set_bit(Faulty, &r->flags);
2044 static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2046 struct mddev *mddev = &rs->md;
2047 struct dm_raid_superblock *sb;
2049 if (rs_is_raid0(rs) || !rdev->sb_page)
2052 sb = page_address(rdev->sb_page);
2055 * If mddev->events is not set, we know we have not yet initialized
2058 if (!mddev->events && super_init_validation(rs, rdev))
2061 if (le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2062 rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2066 if (sb->incompat_features) {
2067 rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2071 /* Enable bitmap creation for RAID levels != 0 */
2072 mddev->bitmap_info.offset = rt_is_raid0(rs->raid_type) ? 0 : to_sector(4096);
2073 rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2075 if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2076 /* Retrieve device size stored in superblock to be prepared for shrink */
2077 rdev->sectors = le64_to_cpu(sb->sectors);
2078 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2079 if (rdev->recovery_offset == MaxSector)
2080 set_bit(In_sync, &rdev->flags);
2082 * If no reshape in progress -> we're recovering single
2083 * disk(s) and have to set the device(s) to out-of-sync
2085 else if (rs->md.reshape_position == MaxSector)
2086 clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2090 * If a device comes back, set it as not In_sync and no longer faulty.
2092 if (test_and_clear_bit(Faulty, &rdev->flags)) {
2093 rdev->recovery_offset = 0;
2094 clear_bit(In_sync, &rdev->flags);
2095 rdev->saved_raid_disk = rdev->raid_disk;
2098 /* Reshape support -> restore repective data offsets */
2099 rdev->data_offset = le64_to_cpu(sb->data_offset);
2100 rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2106 * Analyse superblocks and select the freshest.
2108 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2111 struct raid_dev *dev;
2112 struct md_rdev *rdev, *tmp, *freshest;
2113 struct mddev *mddev = &rs->md;
2116 rdev_for_each_safe(rdev, tmp, mddev) {
2118 * Skipping super_load due to CTR_FLAG_SYNC will cause
2119 * the array to undergo initialization again as
2120 * though it were new. This is the intended effect
2121 * of the "sync" directive.
2123 * When reshaping capability is added, we must ensure
2124 * that the "sync" directive is disallowed during the
2127 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2130 if (!rdev->meta_bdev)
2133 r = super_load(rdev, freshest);
2142 dev = container_of(rdev, struct raid_dev, rdev);
2144 dm_put_device(ti, dev->meta_dev);
2146 dev->meta_dev = NULL;
2147 rdev->meta_bdev = NULL;
2150 put_page(rdev->sb_page);
2152 rdev->sb_page = NULL;
2154 rdev->sb_loaded = 0;
2157 * We might be able to salvage the data device
2158 * even though the meta device has failed. For
2159 * now, we behave as though '- -' had been
2160 * set for this device in the table.
2163 dm_put_device(ti, dev->data_dev);
2165 dev->data_dev = NULL;
2168 list_del(&rdev->same_set);
2175 if (validate_raid_redundancy(rs)) {
2176 rs->ti->error = "Insufficient redundancy to activate array";
2181 * Validation of the freshest device provides the source of
2182 * validation for the remaining devices.
2184 if (super_validate(rs, freshest)) {
2185 rs->ti->error = "Unable to assemble array: Invalid superblocks";
2189 rdev_for_each(rdev, mddev)
2190 if ((rdev != freshest) && super_validate(rs, rdev))
2197 * Adjust data_offset and new_data_offset on all disk members of @rs
2198 * for out of place reshaping if requested by contructor
2200 * We need free space at the beginning of each raid disk for forward
2201 * and at the end for backward reshapes which userspace has to provide
2202 * via remapping/reordering of space.
2204 static int rs_adjust_data_offsets(struct raid_set *rs)
2206 sector_t data_offset = 0, new_data_offset = 0;
2207 struct md_rdev *rdev;
2209 /* Constructor did not request data offset change */
2210 if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2211 if (!rs_is_reshapable(rs))
2217 /* HM FIXME: get InSync raid_dev? */
2218 rdev = &rs->dev[0].rdev;
2220 if (rs->delta_disks < 0) {
2222 * Removing disks (reshaping backwards):
2224 * - before reshape: data is at offset 0 and free space
2225 * is at end of each component LV
2227 * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2230 new_data_offset = rs->data_offset;
2232 } else if (rs->delta_disks > 0) {
2234 * Adding disks (reshaping forwards):
2236 * - before reshape: data is at offset rs->data_offset != 0 and
2237 * free space is at begin of each component LV
2239 * - after reshape: data is at offset 0 on each component LV
2241 data_offset = rs->data_offset;
2242 new_data_offset = 0;
2246 * User space passes in 0 for data offset after having removed reshape space
2248 * - or - (data offset != 0)
2250 * Changing RAID layout or chunk size -> toggle offsets
2252 * - before reshape: data is at offset rs->data_offset 0 and
2253 * free space is at end of each component LV
2255 * data is at offset rs->data_offset != 0 and
2256 * free space is at begin of each component LV
2258 * - after reshape: data is at offset 0 if i was at offset != 0
2259 * of at offset != 0 if it was at offset 0
2260 * on each component LV
2263 data_offset = rs->data_offset ? rdev->data_offset : 0;
2264 new_data_offset = data_offset ? 0 : rs->data_offset;
2265 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2269 * Make sure we got a minimum amount of free sectors per device
2271 if (rs->data_offset &&
2272 to_sector(i_size_read(rdev->bdev->bd_inode)) - rdev->sectors < MIN_FREE_RESHAPE_SPACE) {
2273 rs->ti->error = data_offset ? "No space for forward reshape" :
2274 "No space for backward reshape";
2278 /* Adjust data offsets on all rdevs */
2279 rdev_for_each(rdev, &rs->md) {
2280 rdev->data_offset = data_offset;
2281 rdev->new_data_offset = new_data_offset;
2287 /* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2288 static void __reorder_raid_disk_indexes(struct raid_set *rs)
2291 struct md_rdev *rdev;
2293 rdev_for_each(rdev, &rs->md) {
2294 rdev->raid_disk = i++;
2295 rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2300 * Setup @rs for takeover by a different raid level
2302 static int rs_setup_takeover(struct raid_set *rs)
2304 struct mddev *mddev = &rs->md;
2305 struct md_rdev *rdev;
2306 unsigned int d = mddev->raid_disks = rs->raid_disks;
2307 sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2309 if (rt_is_raid10(rs->raid_type)) {
2310 if (mddev->level == 0) {
2311 /* Userpace reordered disks -> adjust raid_disk indexes */
2312 __reorder_raid_disk_indexes(rs);
2314 /* raid0 -> raid10_far layout */
2315 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2317 } else if (mddev->level == 1)
2318 /* raid1 -> raid10_near layout */
2319 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2326 clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2327 mddev->recovery_cp = MaxSector;
2330 rdev = &rs->dev[d].rdev;
2332 if (test_bit(d, (void *) rs->rebuild_disks)) {
2333 clear_bit(In_sync, &rdev->flags);
2334 clear_bit(Faulty, &rdev->flags);
2335 mddev->recovery_cp = rdev->recovery_offset = 0;
2336 /* Bitmap has to be created when we do an "up" takeover */
2337 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2340 rdev->new_data_offset = new_data_offset;
2347 * Enable/disable discard support on RAID set depending on
2348 * RAID level and discard properties of underlying RAID members.
2350 static void configure_discard_support(struct raid_set *rs)
2354 struct dm_target *ti = rs->ti;
2356 /* Assume discards not supported until after checks below. */
2357 ti->discards_supported = false;
2359 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */
2360 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6);
2362 for (i = 0; i < rs->md.raid_disks; i++) {
2363 struct request_queue *q;
2365 if (!rs->dev[i].rdev.bdev)
2368 q = bdev_get_queue(rs->dev[i].rdev.bdev);
2369 if (!q || !blk_queue_discard(q))
2373 if (!q->limits.discard_zeroes_data)
2375 if (!devices_handle_discard_safely) {
2376 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2377 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2383 /* All RAID members properly support discards */
2384 ti->discards_supported = true;
2387 * RAID1 and RAID10 personalities require bio splitting,
2388 * RAID0/4/5/6 don't and process large discard bios properly.
2390 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10);
2391 ti->num_discard_bios = 1;
2395 * Construct a RAID0/1/10/4/5/6 mapping:
2397 * <raid_type> <#raid_params> <raid_params>{0,} \
2398 * <#raid_devs> [<meta_dev1> <dev1>]{1,}
2400 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for
2401 * details on possible <raid_params>.
2403 * Userspace is free to initialize the metadata devices, hence the superblocks to
2404 * enforce recreation based on the passed in table parameters.
2407 static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv)
2410 struct raid_type *rt;
2411 unsigned num_raid_params, num_raid_devs;
2412 struct raid_set *rs = NULL;
2414 struct dm_arg_set as = { argc, argv }, as_nrd;
2415 struct dm_arg _args[] = {
2416 { 0, as.argc, "Cannot understand number of raid parameters" },
2417 { 1, 254, "Cannot understand number of raid devices parameters" }
2420 /* Must have <raid_type> */
2421 arg = dm_shift_arg(&as);
2423 ti->error = "No arguments";
2427 rt = get_raid_type(arg);
2429 ti->error = "Unrecognised raid_type";
2433 /* Must have <#raid_params> */
2434 if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
2437 /* number of raid device tupples <meta_dev data_dev> */
2439 dm_consume_args(&as_nrd, num_raid_params);
2440 _args[1].max = (as_nrd.argc - 1) / 2;
2441 if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
2444 if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
2445 ti->error = "Invalid number of supplied raid devices";
2449 rs = raid_set_alloc(ti, rt, num_raid_devs);
2453 r = parse_raid_params(rs, &as, num_raid_params);
2457 r = parse_dev_params(rs, &as);
2461 rs->md.sync_super = super_sync;
2463 r = rs_set_dev_and_array_sectors(rs, false);
2468 * Backup any new raid set level, layout, ...
2469 * requested to be able to compare to superblock
2470 * members for conversion decisions.
2472 rs_config_backup(rs);
2474 r = analyse_superblocks(ti, rs);
2478 INIT_WORK(&rs->md.event_work, do_table_event);
2480 ti->num_flush_bios = 1;
2482 /* Restore any requested new layout for conversion decision */
2483 rs_config_restore(rs);
2486 * If a takeover is needed, just set the level to
2487 * the new requested one and allow the raid set to run.
2489 if (rs_takeover_requested(rs)) {
2490 r = rs_check_takeover(rs);
2494 r = rs_setup_takeover(rs);
2498 /* Tell preresume to update superblocks with new layout */
2499 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2501 } else if (rs_reshape_requested(rs)) {
2502 rs_set_cur(rs); /* Dummy to reject, fill in */
2506 /* If constructor requested it, change data and new_data offsets */
2507 r = rs_adjust_data_offsets(rs);
2511 /* Start raid set read-only and assumed clean to change in raid_resume() */
2514 set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
2516 /* Has to be held on running the array */
2517 mddev_lock_nointr(&rs->md);
2518 r = md_run(&rs->md);
2519 rs->md.in_sync = 0; /* Assume already marked dirty */
2520 mddev_unlock(&rs->md);
2523 ti->error = "Fail to run raid array";
2527 if (ti->len != rs->md.array_sectors) {
2528 ti->error = "Array size does not match requested target length";
2532 rs->callbacks.congested_fn = raid_is_congested;
2533 dm_table_add_target_callbacks(ti->table, &rs->callbacks);
2535 mddev_suspend(&rs->md);
2546 static void raid_dtr(struct dm_target *ti)
2548 struct raid_set *rs = ti->private;
2550 list_del_init(&rs->callbacks.list);
2555 static int raid_map(struct dm_target *ti, struct bio *bio)
2557 struct raid_set *rs = ti->private;
2558 struct mddev *mddev = &rs->md;
2560 mddev->pers->make_request(mddev, bio);
2562 return DM_MAPIO_SUBMITTED;
2565 /* Return string describing the current sync action of @mddev */
2566 static const char *decipher_sync_action(struct mddev *mddev)
2568 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
2571 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2572 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
2573 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
2576 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
2577 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2579 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
2584 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
2592 * Return status string @rdev
2594 * Status characters:
2596 * 'D' = Dead/Failed device
2597 * 'a' = Alive but not in-sync
2598 * 'A' = Alive and in-sync
2600 static const char *__raid_dev_status(struct md_rdev *rdev, bool array_in_sync)
2602 if (test_bit(Faulty, &rdev->flags))
2604 else if (!array_in_sync || !test_bit(In_sync, &rdev->flags))
2610 /* Helper to return resync/reshape progress for @rs and @array_in_sync */
2611 static sector_t rs_get_progress(struct raid_set *rs,
2612 sector_t resync_max_sectors, bool *array_in_sync)
2614 sector_t r, recovery_cp, curr_resync_completed;
2615 struct mddev *mddev = &rs->md;
2617 curr_resync_completed = mddev->curr_resync_completed ?: mddev->recovery_cp;
2618 recovery_cp = mddev->recovery_cp;
2619 *array_in_sync = false;
2621 if (rs_is_raid0(rs)) {
2622 r = resync_max_sectors;
2623 *array_in_sync = true;
2626 r = mddev->reshape_position;
2628 /* Reshape is relative to the array size */
2629 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ||
2631 if (r == MaxSector) {
2632 *array_in_sync = true;
2633 r = resync_max_sectors;
2635 /* Got to reverse on backward reshape */
2636 if (mddev->reshape_backwards)
2637 r = mddev->array_sectors - r;
2639 /* Devide by # of data stripes */
2640 sector_div(r, mddev_data_stripes(rs));
2643 /* Sync is relative to the component device size */
2644 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2645 r = curr_resync_completed;
2649 if (r == MaxSector) {
2653 *array_in_sync = true;
2654 r = resync_max_sectors;
2655 } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2657 * If "check" or "repair" is occurring, the raid set has
2658 * undergone an initial sync and the health characters
2659 * should not be 'a' anymore.
2661 *array_in_sync = true;
2663 struct md_rdev *rdev;
2666 * The raid set may be doing an initial sync, or it may
2667 * be rebuilding individual components. If all the
2668 * devices are In_sync, then it is the raid set that is
2669 * being initialized.
2671 rdev_for_each(rdev, mddev)
2672 if (!test_bit(In_sync, &rdev->flags))
2673 *array_in_sync = true;
2675 r = 0; /* HM FIXME: TESTME: https://bugzilla.redhat.com/show_bug.cgi?id=1210637 ? */
2683 /* Helper to return @dev name or "-" if !@dev */
2684 static const char *__get_dev_name(struct dm_dev *dev)
2686 return dev ? dev->name : "-";
2689 static void raid_status(struct dm_target *ti, status_type_t type,
2690 unsigned int status_flags, char *result, unsigned int maxlen)
2692 struct raid_set *rs = ti->private;
2693 struct mddev *mddev = &rs->md;
2694 struct r5conf *conf = mddev->private;
2695 int max_nr_stripes = conf ? conf->max_nr_stripes : 0;
2697 unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
2698 unsigned int sz = 0;
2699 unsigned int write_mostly_params = 0;
2700 sector_t progress, resync_max_sectors, resync_mismatches;
2701 const char *sync_action;
2702 struct raid_type *rt;
2703 struct md_rdev *rdev;
2706 case STATUSTYPE_INFO:
2707 /* *Should* always succeed */
2708 rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
2712 DMEMIT("%s %d ", rt ? rt->name : "unknown", mddev->raid_disks);
2714 /* Access most recent mddev properties for status output */
2716 /* Get sensible max sectors even if raid set not yet started */
2717 resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
2718 mddev->resync_max_sectors : mddev->dev_sectors;
2719 progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync);
2720 resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
2721 (unsigned int) atomic64_read(&mddev->resync_mismatches) : 0;
2722 sync_action = decipher_sync_action(&rs->md);
2724 /* HM FIXME: do we want another state char for raid0? It shows 'D' or 'A' now */
2725 rdev_for_each(rdev, mddev)
2726 DMEMIT(__raid_dev_status(rdev, array_in_sync));
2729 * In-sync/Reshape ratio:
2730 * The in-sync ratio shows the progress of:
2731 * - Initializing the raid set
2732 * - Rebuilding a subset of devices of the raid set
2733 * The user can distinguish between the two by referring
2734 * to the status characters.
2736 * The reshape ratio shows the progress of
2737 * changing the raid layout or the number of
2738 * disks of a raid set
2740 DMEMIT(" %llu/%llu", (unsigned long long) progress,
2741 (unsigned long long) resync_max_sectors);
2747 * See Documentation/device-mapper/dm-raid.txt for
2748 * information on each of these states.
2750 DMEMIT(" %s", sync_action);
2755 * resync_mismatches/mismatch_cnt
2756 * This field shows the number of discrepancies found when
2757 * performing a "check" of the raid set.
2759 DMEMIT(" %llu", (unsigned long long) resync_mismatches);
2764 * data_offset (needed for out of space reshaping)
2765 * This field shows the data offset into the data
2766 * image LV where the first stripes data starts.
2768 * We keep data_offset equal on all raid disks of the set,
2769 * so retrieving it from the first raid disk is sufficient.
2771 DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
2774 case STATUSTYPE_TABLE:
2775 /* Report the table line string you would use to construct this raid set */
2777 /* Calculate raid parameter count */
2778 rdev_for_each(rdev, mddev)
2779 if (test_bit(WriteMostly, &rdev->flags))
2780 write_mostly_params += 2;
2781 raid_param_cnt += memweight(rs->rebuild_disks,
2782 DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks)) * 2 +
2783 write_mostly_params +
2784 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
2785 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
2786 /* Emit table line */
2787 DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
2788 if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
2789 DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
2790 raid10_md_layout_to_format(mddev->layout));
2791 if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
2792 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
2793 raid10_md_layout_to_copies(mddev->layout));
2794 if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2795 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
2796 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2797 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
2798 if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
2799 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
2800 (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
2801 if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
2802 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
2803 (unsigned long long) rs->data_offset);
2804 if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
2805 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
2806 mddev->bitmap_info.daemon_sleep);
2807 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
2808 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
2809 mddev->delta_disks);
2810 if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
2811 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
2813 rdev_for_each(rdev, mddev)
2814 if (test_bit(rdev->raid_disk, (void *) rs->rebuild_disks))
2815 DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD),
2817 rdev_for_each(rdev, mddev)
2818 if (test_bit(WriteMostly, &rdev->flags))
2819 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
2821 if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
2822 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
2823 mddev->bitmap_info.max_write_behind);
2824 if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
2825 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
2826 mddev->sync_speed_max);
2827 if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
2828 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
2829 mddev->sync_speed_min);
2830 DMEMIT(" %d", rs->raid_disks);
2831 rdev_for_each(rdev, mddev) {
2832 struct raid_dev *rd = container_of(rdev, struct raid_dev, rdev);
2834 DMEMIT(" %s %s", __get_dev_name(rd->meta_dev),
2835 __get_dev_name(rd->data_dev));
2840 static int raid_message(struct dm_target *ti, unsigned argc, char **argv)
2842 struct raid_set *rs = ti->private;
2843 struct mddev *mddev = &rs->md;
2845 if (!mddev->pers || !mddev->pers->sync_request)
2848 if (!strcasecmp(argv[0], "frozen"))
2849 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
2851 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
2853 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
2854 if (mddev->sync_thread) {
2855 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2856 md_reap_sync_thread(mddev);
2858 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2859 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
2861 else if (!strcasecmp(argv[0], "resync"))
2862 ; /* MD_RECOVERY_NEEDED set below */
2863 else if (!strcasecmp(argv[0], "recover"))
2864 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
2866 if (!strcasecmp(argv[0], "check"))
2867 set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
2868 else if (!!strcasecmp(argv[0], "repair"))
2870 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
2871 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
2873 if (mddev->ro == 2) {
2874 /* A write to sync_action is enough to justify
2875 * canceling read-auto mode
2878 if (!mddev->suspended && mddev->sync_thread)
2879 md_wakeup_thread(mddev->sync_thread);
2881 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2882 if (!mddev->suspended && mddev->thread)
2883 md_wakeup_thread(mddev->thread);
2888 static int raid_iterate_devices(struct dm_target *ti,
2889 iterate_devices_callout_fn fn, void *data)
2891 struct raid_set *rs = ti->private;
2895 for (i = 0; !r && i < rs->md.raid_disks; i++)
2896 if (rs->dev[i].data_dev)
2898 rs->dev[i].data_dev,
2899 0, /* No offset on data devs */
2906 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
2908 struct raid_set *rs = ti->private;
2909 unsigned chunk_size = rs->md.chunk_sectors << 9;
2910 struct r5conf *conf = rs->md.private;
2912 blk_limits_io_min(limits, chunk_size);
2913 blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded));
2916 static void raid_presuspend(struct dm_target *ti)
2918 struct raid_set *rs = ti->private;
2920 md_stop_writes(&rs->md);
2923 static void raid_postsuspend(struct dm_target *ti)
2925 struct raid_set *rs = ti->private;
2927 mddev_suspend(&rs->md);
2930 static void attempt_restore_of_faulty_devices(struct raid_set *rs)
2933 uint64_t failed_devices, cleared_failed_devices = 0;
2934 unsigned long flags;
2935 struct dm_raid_superblock *sb;
2938 for (i = 0; i < rs->md.raid_disks; i++) {
2939 r = &rs->dev[i].rdev;
2940 if (test_bit(Faulty, &r->flags) && r->sb_page &&
2941 sync_page_io(r, 0, r->sb_size, r->sb_page, REQ_OP_READ, 0,
2943 DMINFO("Faulty %s device #%d has readable super block."
2944 " Attempting to revive it.",
2945 rs->raid_type->name, i);
2948 * Faulty bit may be set, but sometimes the array can
2949 * be suspended before the personalities can respond
2950 * by removing the device from the array (i.e. calling
2951 * 'hot_remove_disk'). If they haven't yet removed
2952 * the failed device, its 'raid_disk' number will be
2953 * '>= 0' - meaning we must call this function
2956 if ((r->raid_disk >= 0) &&
2957 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0))
2958 /* Failed to revive this device, try next */
2962 r->saved_raid_disk = i;
2964 clear_bit(Faulty, &r->flags);
2965 clear_bit(WriteErrorSeen, &r->flags);
2966 clear_bit(In_sync, &r->flags);
2967 if (r->mddev->pers->hot_add_disk(r->mddev, r)) {
2969 r->saved_raid_disk = -1;
2972 r->recovery_offset = 0;
2973 cleared_failed_devices |= 1 << i;
2977 if (cleared_failed_devices) {
2978 rdev_for_each(r, &rs->md) {
2979 sb = page_address(r->sb_page);
2980 failed_devices = le64_to_cpu(sb->failed_devices);
2981 failed_devices &= ~cleared_failed_devices;
2982 sb->failed_devices = cpu_to_le64(failed_devices);
2987 static int __load_dirty_region_bitmap(struct raid_set *rs)
2991 /* Try loading the bitmap unless "raid0", which does not have one */
2992 if (!rs_is_raid0(rs) &&
2993 !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
2994 r = bitmap_load(&rs->md);
2996 DMERR("Failed to load bitmap");
3002 static int raid_preresume(struct dm_target *ti)
3004 struct raid_set *rs = ti->private;
3005 struct mddev *mddev = &rs->md;
3007 /* This is a resume after a suspend of the set -> it's already started */
3008 if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
3012 * The superblocks need to be updated on disk if the
3013 * array is new or __load_dirty_region_bitmap will overwrite them
3014 * in core with old data.
3016 * In case the array got modified (takeover/reshape/resize)
3017 * or the data offsets on the component devices changed, they
3018 * have to be updated as well.
3020 * Have to switch to readwrite and back in order to
3021 * allow for the superblock updates.
3023 if (test_and_clear_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags)) {
3024 set_bit(MD_CHANGE_DEVS, &mddev->flags);
3026 md_update_sb(mddev, 1);
3031 * Disable/enable discard support on raid set after any
3032 * conversion, because devices can have been added
3034 configure_discard_support(rs);
3036 /* Load the bitmap from disk unless raid0 */
3037 return __load_dirty_region_bitmap(rs);
3040 static void raid_resume(struct dm_target *ti)
3042 struct raid_set *rs = ti->private;
3043 struct mddev *mddev = &rs->md;
3045 if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
3047 * A secondary resume while the device is active.
3048 * Take this opportunity to check whether any failed
3049 * devices are reachable again.
3051 attempt_restore_of_faulty_devices(rs);
3056 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3058 if (mddev->suspended)
3059 mddev_resume(mddev);
3062 static struct target_type raid_target = {
3064 .version = {1, 9, 0},
3065 .module = THIS_MODULE,
3069 .status = raid_status,
3070 .message = raid_message,
3071 .iterate_devices = raid_iterate_devices,
3072 .io_hints = raid_io_hints,
3073 .presuspend = raid_presuspend,
3074 .postsuspend = raid_postsuspend,
3075 .preresume = raid_preresume,
3076 .resume = raid_resume,
3079 static int __init dm_raid_init(void)
3081 DMINFO("Loading target version %u.%u.%u",
3082 raid_target.version[0],
3083 raid_target.version[1],
3084 raid_target.version[2]);
3085 return dm_register_target(&raid_target);
3088 static void __exit dm_raid_exit(void)
3090 dm_unregister_target(&raid_target);
3093 module_init(dm_raid_init);
3094 module_exit(dm_raid_exit);
3096 module_param(devices_handle_discard_safely, bool, 0644);
3097 MODULE_PARM_DESC(devices_handle_discard_safely,
3098 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
3100 MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
3101 MODULE_ALIAS("dm-raid0");
3102 MODULE_ALIAS("dm-raid1");
3103 MODULE_ALIAS("dm-raid10");
3104 MODULE_ALIAS("dm-raid4");
3105 MODULE_ALIAS("dm-raid5");
3106 MODULE_ALIAS("dm-raid6");
3107 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
3108 MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
3109 MODULE_LICENSE("GPL");