2 * Copyright (C) 2010-2011 Neil Brown
3 * Copyright (C) 2010-2014 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"
21 static bool devices_handle_discard_safely
= false;
24 * The following flags are used by dm-raid.c to set up the array state.
25 * They must be cleared before md_run is called.
27 #define FirstUse 10 /* rdev flag */
31 * Two DM devices, one to hold metadata and one to hold the
32 * actual data/parity. The reason for this is to not confuse
33 * ti->len and give more flexibility in altering size and
36 * While it is possible for this device to be associated
37 * with a different physical device than the data_dev, it
38 * is intended for it to be the same.
39 * |--------- Physical Device ---------|
40 * |- meta_dev -|------ data_dev ------|
42 struct dm_dev
*meta_dev
;
43 struct dm_dev
*data_dev
;
48 * Flags for rs->print_flags field.
51 #define DMPF_NOSYNC 0x2
52 #define DMPF_REBUILD 0x4
53 #define DMPF_DAEMON_SLEEP 0x8
54 #define DMPF_MIN_RECOVERY_RATE 0x10
55 #define DMPF_MAX_RECOVERY_RATE 0x20
56 #define DMPF_MAX_WRITE_BEHIND 0x40
57 #define DMPF_STRIPE_CACHE 0x80
58 #define DMPF_REGION_SIZE 0x100
59 #define DMPF_RAID10_COPIES 0x200
60 #define DMPF_RAID10_FORMAT 0x400
65 uint32_t bitmap_loaded
;
69 struct raid_type
*raid_type
;
70 struct dm_target_callbacks callbacks
;
72 struct raid_dev dev
[0];
75 /* Supported raid types and properties. */
76 static struct raid_type
{
77 const char *name
; /* RAID algorithm. */
78 const char *descr
; /* Descriptor text for logging. */
79 const unsigned parity_devs
; /* # of parity devices. */
80 const unsigned minimal_devs
; /* minimal # of devices in set. */
81 const unsigned level
; /* RAID level. */
82 const unsigned algorithm
; /* RAID algorithm. */
84 {"raid1", "RAID1 (mirroring)", 0, 2, 1, 0 /* NONE */},
85 {"raid10", "RAID10 (striped mirrors)", 0, 2, 10, UINT_MAX
/* Varies */},
86 {"raid4", "RAID4 (dedicated parity disk)", 1, 2, 5, ALGORITHM_PARITY_0
},
87 {"raid5_la", "RAID5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC
},
88 {"raid5_ra", "RAID5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC
},
89 {"raid5_ls", "RAID5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC
},
90 {"raid5_rs", "RAID5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC
},
91 {"raid6_zr", "RAID6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART
},
92 {"raid6_nr", "RAID6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART
},
93 {"raid6_nc", "RAID6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE
}
96 static char *raid10_md_layout_to_format(int layout
)
99 * Bit 16 and 17 stand for "offset" and "use_far_sets"
100 * Refer to MD's raid10.c for details
102 if ((layout
& 0x10000) && (layout
& 0x20000))
105 if ((layout
& 0xFF) > 1)
111 static unsigned raid10_md_layout_to_copies(int layout
)
113 if ((layout
& 0xFF) > 1)
114 return layout
& 0xFF;
115 return (layout
>> 8) & 0xFF;
118 static int raid10_format_to_md_layout(char *format
, unsigned copies
)
120 unsigned n
= 1, f
= 1;
122 if (!strcmp("near", format
))
127 if (!strcmp("offset", format
))
128 return 0x30000 | (f
<< 8) | n
;
130 if (!strcmp("far", format
))
131 return 0x20000 | (f
<< 8) | n
;
136 static struct raid_type
*get_raid_type(char *name
)
140 for (i
= 0; i
< ARRAY_SIZE(raid_types
); i
++)
141 if (!strcmp(raid_types
[i
].name
, name
))
142 return &raid_types
[i
];
147 static struct raid_set
*context_alloc(struct dm_target
*ti
, struct raid_type
*raid_type
, unsigned raid_devs
)
152 if (raid_devs
<= raid_type
->parity_devs
) {
153 ti
->error
= "Insufficient number of devices";
154 return ERR_PTR(-EINVAL
);
157 rs
= kzalloc(sizeof(*rs
) + raid_devs
* sizeof(rs
->dev
[0]), GFP_KERNEL
);
159 ti
->error
= "Cannot allocate raid context";
160 return ERR_PTR(-ENOMEM
);
166 rs
->raid_type
= raid_type
;
167 rs
->md
.raid_disks
= raid_devs
;
168 rs
->md
.level
= raid_type
->level
;
169 rs
->md
.new_level
= rs
->md
.level
;
170 rs
->md
.layout
= raid_type
->algorithm
;
171 rs
->md
.new_layout
= rs
->md
.layout
;
172 rs
->md
.delta_disks
= 0;
173 rs
->md
.recovery_cp
= 0;
175 for (i
= 0; i
< raid_devs
; i
++)
176 md_rdev_init(&rs
->dev
[i
].rdev
);
179 * Remaining items to be initialized by further RAID params:
182 * rs->md.chunk_sectors
183 * rs->md.new_chunk_sectors
190 static void context_free(struct raid_set
*rs
)
194 for (i
= 0; i
< rs
->md
.raid_disks
; i
++) {
195 if (rs
->dev
[i
].meta_dev
)
196 dm_put_device(rs
->ti
, rs
->dev
[i
].meta_dev
);
197 md_rdev_clear(&rs
->dev
[i
].rdev
);
198 if (rs
->dev
[i
].data_dev
)
199 dm_put_device(rs
->ti
, rs
->dev
[i
].data_dev
);
206 * For every device we have two words
207 * <meta_dev>: meta device name or '-' if missing
208 * <data_dev>: data device name or '-' if missing
210 * The following are permitted:
213 * <meta_dev> <data_dev>
215 * The following is not allowed:
218 * This code parses those words. If there is a failure,
219 * the caller must use context_free to unwind the operations.
221 static int dev_parms(struct raid_set
*rs
, char **argv
)
225 int metadata_available
= 0;
228 for (i
= 0; i
< rs
->md
.raid_disks
; i
++, argv
+= 2) {
229 rs
->dev
[i
].rdev
.raid_disk
= i
;
231 rs
->dev
[i
].meta_dev
= NULL
;
232 rs
->dev
[i
].data_dev
= NULL
;
235 * There are no offsets, since there is a separate device
236 * for data and metadata.
238 rs
->dev
[i
].rdev
.data_offset
= 0;
239 rs
->dev
[i
].rdev
.mddev
= &rs
->md
;
241 if (strcmp(argv
[0], "-")) {
242 ret
= dm_get_device(rs
->ti
, argv
[0],
243 dm_table_get_mode(rs
->ti
->table
),
244 &rs
->dev
[i
].meta_dev
);
245 rs
->ti
->error
= "RAID metadata device lookup failure";
249 rs
->dev
[i
].rdev
.sb_page
= alloc_page(GFP_KERNEL
);
250 if (!rs
->dev
[i
].rdev
.sb_page
)
254 if (!strcmp(argv
[1], "-")) {
255 if (!test_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
) &&
256 (!rs
->dev
[i
].rdev
.recovery_offset
)) {
257 rs
->ti
->error
= "Drive designated for rebuild not specified";
261 rs
->ti
->error
= "No data device supplied with metadata device";
262 if (rs
->dev
[i
].meta_dev
)
268 ret
= dm_get_device(rs
->ti
, argv
[1],
269 dm_table_get_mode(rs
->ti
->table
),
270 &rs
->dev
[i
].data_dev
);
272 rs
->ti
->error
= "RAID device lookup failure";
276 if (rs
->dev
[i
].meta_dev
) {
277 metadata_available
= 1;
278 rs
->dev
[i
].rdev
.meta_bdev
= rs
->dev
[i
].meta_dev
->bdev
;
280 rs
->dev
[i
].rdev
.bdev
= rs
->dev
[i
].data_dev
->bdev
;
281 list_add(&rs
->dev
[i
].rdev
.same_set
, &rs
->md
.disks
);
282 if (!test_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
))
286 if (metadata_available
) {
288 rs
->md
.persistent
= 1;
289 rs
->md
.major_version
= 2;
290 } else if (rebuild
&& !rs
->md
.recovery_cp
) {
292 * Without metadata, we will not be able to tell if the array
293 * is in-sync or not - we must assume it is not. Therefore,
294 * it is impossible to rebuild a drive.
296 * Even if there is metadata, the on-disk information may
297 * indicate that the array is not in-sync and it will then
300 * User could specify 'nosync' option if desperate.
302 DMERR("Unable to rebuild drive while array is not in-sync");
303 rs
->ti
->error
= "RAID device lookup failure";
311 * validate_region_size
313 * @region_size: region size in sectors. If 0, pick a size (4MiB default).
315 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
316 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
318 * Returns: 0 on success, -EINVAL on failure.
320 static int validate_region_size(struct raid_set
*rs
, unsigned long region_size
)
322 unsigned long min_region_size
= rs
->ti
->len
/ (1 << 21);
326 * Choose a reasonable default. All figures in sectors.
328 if (min_region_size
> (1 << 13)) {
329 /* If not a power of 2, make it the next power of 2 */
330 if (min_region_size
& (min_region_size
- 1))
331 region_size
= 1 << fls(region_size
);
332 DMINFO("Choosing default region size of %lu sectors",
335 DMINFO("Choosing default region size of 4MiB");
336 region_size
= 1 << 13; /* sectors */
340 * Validate user-supplied value.
342 if (region_size
> rs
->ti
->len
) {
343 rs
->ti
->error
= "Supplied region size is too large";
347 if (region_size
< min_region_size
) {
348 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
349 region_size
, min_region_size
);
350 rs
->ti
->error
= "Supplied region size is too small";
354 if (!is_power_of_2(region_size
)) {
355 rs
->ti
->error
= "Region size is not a power of 2";
359 if (region_size
< rs
->md
.chunk_sectors
) {
360 rs
->ti
->error
= "Region size is smaller than the chunk size";
366 * Convert sectors to bytes.
368 rs
->md
.bitmap_info
.chunksize
= (region_size
<< 9);
374 * validate_raid_redundancy
377 * Determine if there are enough devices in the array that haven't
378 * failed (or are being rebuilt) to form a usable array.
380 * Returns: 0 on success, -EINVAL on failure.
382 static int validate_raid_redundancy(struct raid_set
*rs
)
384 unsigned i
, rebuild_cnt
= 0;
385 unsigned rebuilds_per_group
= 0, copies
, d
;
386 unsigned group_size
, last_group_start
;
388 for (i
= 0; i
< rs
->md
.raid_disks
; i
++)
389 if (!test_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
) ||
390 !rs
->dev
[i
].rdev
.sb_page
)
393 switch (rs
->raid_type
->level
) {
395 if (rebuild_cnt
>= rs
->md
.raid_disks
)
401 if (rebuild_cnt
> rs
->raid_type
->parity_devs
)
405 copies
= raid10_md_layout_to_copies(rs
->md
.layout
);
406 if (rebuild_cnt
< copies
)
410 * It is possible to have a higher rebuild count for RAID10,
411 * as long as the failed devices occur in different mirror
412 * groups (i.e. different stripes).
414 * When checking "near" format, make sure no adjacent devices
415 * have failed beyond what can be handled. In addition to the
416 * simple case where the number of devices is a multiple of the
417 * number of copies, we must also handle cases where the number
418 * of devices is not a multiple of the number of copies.
419 * E.g. dev1 dev2 dev3 dev4 dev5
423 if (!strcmp("near", raid10_md_layout_to_format(rs
->md
.layout
))) {
424 for (i
= 0; i
< rs
->md
.raid_disks
* copies
; i
++) {
426 rebuilds_per_group
= 0;
427 d
= i
% rs
->md
.raid_disks
;
428 if ((!rs
->dev
[d
].rdev
.sb_page
||
429 !test_bit(In_sync
, &rs
->dev
[d
].rdev
.flags
)) &&
430 (++rebuilds_per_group
>= copies
))
437 * When checking "far" and "offset" formats, we need to ensure
438 * that the device that holds its copy is not also dead or
439 * being rebuilt. (Note that "far" and "offset" formats only
440 * support two copies right now. These formats also only ever
441 * use the 'use_far_sets' variant.)
443 * This check is somewhat complicated by the need to account
444 * for arrays that are not a multiple of (far) copies. This
445 * results in the need to treat the last (potentially larger)
448 group_size
= (rs
->md
.raid_disks
/ copies
);
449 last_group_start
= (rs
->md
.raid_disks
/ group_size
) - 1;
450 last_group_start
*= group_size
;
451 for (i
= 0; i
< rs
->md
.raid_disks
; i
++) {
452 if (!(i
% copies
) && !(i
> last_group_start
))
453 rebuilds_per_group
= 0;
454 if ((!rs
->dev
[i
].rdev
.sb_page
||
455 !test_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
)) &&
456 (++rebuilds_per_group
>= copies
))
472 * Possible arguments are...
473 * <chunk_size> [optional_args]
475 * Argument definitions
476 * <chunk_size> The number of sectors per disk that
477 * will form the "stripe"
478 * [[no]sync] Force or prevent recovery of the
480 * [devices_handle_discard_safely] Allow discards on RAID4/5/6; useful if RAID
481 * member device(s) properly support TRIM/UNMAP
482 * [rebuild <idx>] Rebuild the drive indicated by the index
483 * [daemon_sleep <ms>] Time between bitmap daemon work to
485 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
486 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
487 * [write_mostly <idx>] Indicate a write mostly drive via index
488 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
489 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs
490 * [region_size <sectors>] Defines granularity of bitmap
492 * RAID10-only options:
493 * [raid10_copies <# copies>] Number of copies. (Default: 2)
494 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
496 static int parse_raid_params(struct raid_set
*rs
, char **argv
,
497 unsigned num_raid_params
)
499 char *raid10_format
= "near";
500 unsigned raid10_copies
= 2;
502 unsigned long value
, region_size
= 0;
503 sector_t sectors_per_dev
= rs
->ti
->len
;
508 * First, parse the in-order required arguments
509 * "chunk_size" is the only argument of this type.
511 if ((kstrtoul(argv
[0], 10, &value
) < 0)) {
512 rs
->ti
->error
= "Bad chunk size";
514 } else if (rs
->raid_type
->level
== 1) {
516 DMERR("Ignoring chunk size parameter for RAID 1");
518 } else if (!is_power_of_2(value
)) {
519 rs
->ti
->error
= "Chunk size must be a power of 2";
521 } else if (value
< 8) {
522 rs
->ti
->error
= "Chunk size value is too small";
526 rs
->md
.new_chunk_sectors
= rs
->md
.chunk_sectors
= value
;
531 * We set each individual device as In_sync with a completed
532 * 'recovery_offset'. If there has been a device failure or
533 * replacement then one of the following cases applies:
535 * 1) User specifies 'rebuild'.
536 * - Device is reset when param is read.
537 * 2) A new device is supplied.
538 * - No matching superblock found, resets device.
539 * 3) Device failure was transient and returns on reload.
540 * - Failure noticed, resets device for bitmap replay.
541 * 4) Device hadn't completed recovery after previous failure.
542 * - Superblock is read and overrides recovery_offset.
544 * What is found in the superblocks of the devices is always
545 * authoritative, unless 'rebuild' or '[no]sync' was specified.
547 for (i
= 0; i
< rs
->md
.raid_disks
; i
++) {
548 set_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
);
549 rs
->dev
[i
].rdev
.recovery_offset
= MaxSector
;
553 * Second, parse the unordered optional arguments
555 for (i
= 0; i
< num_raid_params
; i
++) {
556 if (!strcasecmp(argv
[i
], "nosync")) {
557 rs
->md
.recovery_cp
= MaxSector
;
558 rs
->print_flags
|= DMPF_NOSYNC
;
561 if (!strcasecmp(argv
[i
], "sync")) {
562 rs
->md
.recovery_cp
= 0;
563 rs
->print_flags
|= DMPF_SYNC
;
567 /* The rest of the optional arguments come in key/value pairs */
568 if ((i
+ 1) >= num_raid_params
) {
569 rs
->ti
->error
= "Wrong number of raid parameters given";
575 /* Parameters that take a string value are checked here. */
576 if (!strcasecmp(key
, "raid10_format")) {
577 if (rs
->raid_type
->level
!= 10) {
578 rs
->ti
->error
= "'raid10_format' is an invalid parameter for this RAID type";
581 if (strcmp("near", argv
[i
]) &&
582 strcmp("far", argv
[i
]) &&
583 strcmp("offset", argv
[i
])) {
584 rs
->ti
->error
= "Invalid 'raid10_format' value given";
587 raid10_format
= argv
[i
];
588 rs
->print_flags
|= DMPF_RAID10_FORMAT
;
592 if (kstrtoul(argv
[i
], 10, &value
) < 0) {
593 rs
->ti
->error
= "Bad numerical argument given in raid params";
597 /* Parameters that take a numeric value are checked here */
598 if (!strcasecmp(key
, "rebuild")) {
599 if (value
>= rs
->md
.raid_disks
) {
600 rs
->ti
->error
= "Invalid rebuild index given";
603 clear_bit(In_sync
, &rs
->dev
[value
].rdev
.flags
);
604 rs
->dev
[value
].rdev
.recovery_offset
= 0;
605 rs
->print_flags
|= DMPF_REBUILD
;
606 } else if (!strcasecmp(key
, "write_mostly")) {
607 if (rs
->raid_type
->level
!= 1) {
608 rs
->ti
->error
= "write_mostly option is only valid for RAID1";
611 if (value
>= rs
->md
.raid_disks
) {
612 rs
->ti
->error
= "Invalid write_mostly drive index given";
615 set_bit(WriteMostly
, &rs
->dev
[value
].rdev
.flags
);
616 } else if (!strcasecmp(key
, "max_write_behind")) {
617 if (rs
->raid_type
->level
!= 1) {
618 rs
->ti
->error
= "max_write_behind option is only valid for RAID1";
621 rs
->print_flags
|= DMPF_MAX_WRITE_BEHIND
;
624 * In device-mapper, we specify things in sectors, but
625 * MD records this value in kB
628 if (value
> COUNTER_MAX
) {
629 rs
->ti
->error
= "Max write-behind limit out of range";
632 rs
->md
.bitmap_info
.max_write_behind
= value
;
633 } else if (!strcasecmp(key
, "daemon_sleep")) {
634 rs
->print_flags
|= DMPF_DAEMON_SLEEP
;
635 if (!value
|| (value
> MAX_SCHEDULE_TIMEOUT
)) {
636 rs
->ti
->error
= "daemon sleep period out of range";
639 rs
->md
.bitmap_info
.daemon_sleep
= value
;
640 } else if (!strcasecmp(key
, "stripe_cache")) {
641 rs
->print_flags
|= DMPF_STRIPE_CACHE
;
644 * In device-mapper, we specify things in sectors, but
645 * MD records this value in kB
649 if ((rs
->raid_type
->level
!= 5) &&
650 (rs
->raid_type
->level
!= 6)) {
651 rs
->ti
->error
= "Inappropriate argument: stripe_cache";
654 if (raid5_set_cache_size(&rs
->md
, (int)value
)) {
655 rs
->ti
->error
= "Bad stripe_cache size";
658 } else if (!strcasecmp(key
, "min_recovery_rate")) {
659 rs
->print_flags
|= DMPF_MIN_RECOVERY_RATE
;
660 if (value
> INT_MAX
) {
661 rs
->ti
->error
= "min_recovery_rate out of range";
664 rs
->md
.sync_speed_min
= (int)value
;
665 } else if (!strcasecmp(key
, "max_recovery_rate")) {
666 rs
->print_flags
|= DMPF_MAX_RECOVERY_RATE
;
667 if (value
> INT_MAX
) {
668 rs
->ti
->error
= "max_recovery_rate out of range";
671 rs
->md
.sync_speed_max
= (int)value
;
672 } else if (!strcasecmp(key
, "region_size")) {
673 rs
->print_flags
|= DMPF_REGION_SIZE
;
675 } else if (!strcasecmp(key
, "raid10_copies") &&
676 (rs
->raid_type
->level
== 10)) {
677 if ((value
< 2) || (value
> 0xFF)) {
678 rs
->ti
->error
= "Bad value for 'raid10_copies'";
681 rs
->print_flags
|= DMPF_RAID10_COPIES
;
682 raid10_copies
= value
;
684 DMERR("Unable to parse RAID parameter: %s", key
);
685 rs
->ti
->error
= "Unable to parse RAID parameters";
690 if (validate_region_size(rs
, region_size
))
693 if (rs
->md
.chunk_sectors
)
694 max_io_len
= rs
->md
.chunk_sectors
;
696 max_io_len
= region_size
;
698 if (dm_set_target_max_io_len(rs
->ti
, max_io_len
))
701 if (rs
->raid_type
->level
== 10) {
702 if (raid10_copies
> rs
->md
.raid_disks
) {
703 rs
->ti
->error
= "Not enough devices to satisfy specification";
708 * If the format is not "near", we only support
709 * two copies at the moment.
711 if (strcmp("near", raid10_format
) && (raid10_copies
> 2)) {
712 rs
->ti
->error
= "Too many copies for given RAID10 format.";
716 /* (Len * #mirrors) / #devices */
717 sectors_per_dev
= rs
->ti
->len
* raid10_copies
;
718 sector_div(sectors_per_dev
, rs
->md
.raid_disks
);
720 rs
->md
.layout
= raid10_format_to_md_layout(raid10_format
,
722 rs
->md
.new_layout
= rs
->md
.layout
;
723 } else if ((rs
->raid_type
->level
> 1) &&
724 sector_div(sectors_per_dev
,
725 (rs
->md
.raid_disks
- rs
->raid_type
->parity_devs
))) {
726 rs
->ti
->error
= "Target length not divisible by number of data devices";
729 rs
->md
.dev_sectors
= sectors_per_dev
;
731 /* Assume there are no metadata devices until the drives are parsed */
732 rs
->md
.persistent
= 0;
738 static void do_table_event(struct work_struct
*ws
)
740 struct raid_set
*rs
= container_of(ws
, struct raid_set
, md
.event_work
);
742 dm_table_event(rs
->ti
->table
);
745 static int raid_is_congested(struct dm_target_callbacks
*cb
, int bits
)
747 struct raid_set
*rs
= container_of(cb
, struct raid_set
, callbacks
);
749 if (rs
->raid_type
->level
== 1)
750 return md_raid1_congested(&rs
->md
, bits
);
752 if (rs
->raid_type
->level
== 10)
753 return md_raid10_congested(&rs
->md
, bits
);
755 return md_raid5_congested(&rs
->md
, bits
);
759 * This structure is never routinely used by userspace, unlike md superblocks.
760 * Devices with this superblock should only ever be accessed via device-mapper.
762 #define DM_RAID_MAGIC 0x64526D44
763 struct dm_raid_superblock
{
764 __le32 magic
; /* "DmRd" */
765 __le32 features
; /* Used to indicate possible future changes */
767 __le32 num_devices
; /* Number of devices in this array. (Max 64) */
768 __le32 array_position
; /* The position of this drive in the array */
770 __le64 events
; /* Incremented by md when superblock updated */
771 __le64 failed_devices
; /* Bit field of devices to indicate failures */
774 * This offset tracks the progress of the repair or replacement of
775 * an individual drive.
777 __le64 disk_recovery_offset
;
780 * This offset tracks the progress of the initial array
781 * synchronisation/parity calculation.
783 __le64 array_resync_offset
;
786 * RAID characteristics
790 __le32 stripe_sectors
;
792 /* Remainder of a logical block is zero-filled when writing (see super_sync()). */
795 static int read_disk_sb(struct md_rdev
*rdev
, int size
)
797 BUG_ON(!rdev
->sb_page
);
802 if (!sync_page_io(rdev
, 0, size
, rdev
->sb_page
, READ
, 1)) {
803 DMERR("Failed to read superblock of device at position %d",
805 md_error(rdev
->mddev
, rdev
);
814 static void super_sync(struct mddev
*mddev
, struct md_rdev
*rdev
)
817 uint64_t failed_devices
;
818 struct dm_raid_superblock
*sb
;
819 struct raid_set
*rs
= container_of(mddev
, struct raid_set
, md
);
821 sb
= page_address(rdev
->sb_page
);
822 failed_devices
= le64_to_cpu(sb
->failed_devices
);
824 for (i
= 0; i
< mddev
->raid_disks
; i
++)
825 if (!rs
->dev
[i
].data_dev
||
826 test_bit(Faulty
, &(rs
->dev
[i
].rdev
.flags
)))
827 failed_devices
|= (1ULL << i
);
829 memset(sb
+ 1, 0, rdev
->sb_size
- sizeof(*sb
));
831 sb
->magic
= cpu_to_le32(DM_RAID_MAGIC
);
832 sb
->features
= cpu_to_le32(0); /* No features yet */
834 sb
->num_devices
= cpu_to_le32(mddev
->raid_disks
);
835 sb
->array_position
= cpu_to_le32(rdev
->raid_disk
);
837 sb
->events
= cpu_to_le64(mddev
->events
);
838 sb
->failed_devices
= cpu_to_le64(failed_devices
);
840 sb
->disk_recovery_offset
= cpu_to_le64(rdev
->recovery_offset
);
841 sb
->array_resync_offset
= cpu_to_le64(mddev
->recovery_cp
);
843 sb
->level
= cpu_to_le32(mddev
->level
);
844 sb
->layout
= cpu_to_le32(mddev
->layout
);
845 sb
->stripe_sectors
= cpu_to_le32(mddev
->chunk_sectors
);
851 * This function creates a superblock if one is not found on the device
852 * and will decide which superblock to use if there's a choice.
854 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
856 static int super_load(struct md_rdev
*rdev
, struct md_rdev
*refdev
)
859 struct dm_raid_superblock
*sb
;
860 struct dm_raid_superblock
*refsb
;
861 uint64_t events_sb
, events_refsb
;
864 rdev
->sb_size
= bdev_logical_block_size(rdev
->meta_bdev
);
865 if (rdev
->sb_size
< sizeof(*sb
) || rdev
->sb_size
> PAGE_SIZE
) {
866 DMERR("superblock size of a logical block is no longer valid");
870 ret
= read_disk_sb(rdev
, rdev
->sb_size
);
874 sb
= page_address(rdev
->sb_page
);
877 * Two cases that we want to write new superblocks and rebuild:
878 * 1) New device (no matching magic number)
879 * 2) Device specified for rebuild (!In_sync w/ offset == 0)
881 if ((sb
->magic
!= cpu_to_le32(DM_RAID_MAGIC
)) ||
882 (!test_bit(In_sync
, &rdev
->flags
) && !rdev
->recovery_offset
)) {
883 super_sync(rdev
->mddev
, rdev
);
885 set_bit(FirstUse
, &rdev
->flags
);
887 /* Force writing of superblocks to disk */
888 set_bit(MD_CHANGE_DEVS
, &rdev
->mddev
->flags
);
890 /* Any superblock is better than none, choose that if given */
891 return refdev
? 0 : 1;
897 events_sb
= le64_to_cpu(sb
->events
);
899 refsb
= page_address(refdev
->sb_page
);
900 events_refsb
= le64_to_cpu(refsb
->events
);
902 return (events_sb
> events_refsb
) ? 1 : 0;
905 static int super_init_validation(struct mddev
*mddev
, struct md_rdev
*rdev
)
908 struct raid_set
*rs
= container_of(mddev
, struct raid_set
, md
);
910 uint64_t failed_devices
;
911 struct dm_raid_superblock
*sb
;
912 uint32_t new_devs
= 0;
913 uint32_t rebuilds
= 0;
915 struct dm_raid_superblock
*sb2
;
917 sb
= page_address(rdev
->sb_page
);
918 events_sb
= le64_to_cpu(sb
->events
);
919 failed_devices
= le64_to_cpu(sb
->failed_devices
);
922 * Initialise to 1 if this is a new superblock.
924 mddev
->events
= events_sb
? : 1;
927 * Reshaping is not currently allowed
929 if (le32_to_cpu(sb
->level
) != mddev
->level
) {
930 DMERR("Reshaping arrays not yet supported. (RAID level change)");
933 if (le32_to_cpu(sb
->layout
) != mddev
->layout
) {
934 DMERR("Reshaping arrays not yet supported. (RAID layout change)");
935 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb
->layout
), mddev
->layout
);
936 DMERR(" Old layout: %s w/ %d copies",
937 raid10_md_layout_to_format(le32_to_cpu(sb
->layout
)),
938 raid10_md_layout_to_copies(le32_to_cpu(sb
->layout
)));
939 DMERR(" New layout: %s w/ %d copies",
940 raid10_md_layout_to_format(mddev
->layout
),
941 raid10_md_layout_to_copies(mddev
->layout
));
944 if (le32_to_cpu(sb
->stripe_sectors
) != mddev
->chunk_sectors
) {
945 DMERR("Reshaping arrays not yet supported. (stripe sectors change)");
949 /* We can only change the number of devices in RAID1 right now */
950 if ((rs
->raid_type
->level
!= 1) &&
951 (le32_to_cpu(sb
->num_devices
) != mddev
->raid_disks
)) {
952 DMERR("Reshaping arrays not yet supported. (device count change)");
956 if (!(rs
->print_flags
& (DMPF_SYNC
| DMPF_NOSYNC
)))
957 mddev
->recovery_cp
= le64_to_cpu(sb
->array_resync_offset
);
960 * During load, we set FirstUse if a new superblock was written.
961 * There are two reasons we might not have a superblock:
962 * 1) The array is brand new - in which case, all of the
963 * devices must have their In_sync bit set. Also,
964 * recovery_cp must be 0, unless forced.
965 * 2) This is a new device being added to an old array
966 * and the new device needs to be rebuilt - in which
967 * case the In_sync bit will /not/ be set and
968 * recovery_cp must be MaxSector.
970 rdev_for_each(r
, mddev
) {
971 if (!test_bit(In_sync
, &r
->flags
)) {
972 DMINFO("Device %d specified for rebuild: "
973 "Clearing superblock", r
->raid_disk
);
975 } else if (test_bit(FirstUse
, &r
->flags
))
980 if (new_devs
== mddev
->raid_disks
) {
981 DMINFO("Superblocks created for new array");
982 set_bit(MD_ARRAY_FIRST_USE
, &mddev
->flags
);
983 } else if (new_devs
) {
984 DMERR("New device injected "
985 "into existing array without 'rebuild' "
986 "parameter specified");
989 } else if (new_devs
) {
990 DMERR("'rebuild' devices cannot be "
991 "injected into an array with other first-time devices");
993 } else if (mddev
->recovery_cp
!= MaxSector
) {
994 DMERR("'rebuild' specified while array is not in-sync");
999 * Now we set the Faulty bit for those devices that are
1000 * recorded in the superblock as failed.
1002 rdev_for_each(r
, mddev
) {
1005 sb2
= page_address(r
->sb_page
);
1006 sb2
->failed_devices
= 0;
1009 * Check for any device re-ordering.
1011 if (!test_bit(FirstUse
, &r
->flags
) && (r
->raid_disk
>= 0)) {
1012 role
= le32_to_cpu(sb2
->array_position
);
1013 if (role
!= r
->raid_disk
) {
1014 if (rs
->raid_type
->level
!= 1) {
1015 rs
->ti
->error
= "Cannot change device "
1016 "positions in RAID array";
1019 DMINFO("RAID1 device #%d now at position #%d",
1020 role
, r
->raid_disk
);
1024 * Partial recovery is performed on
1025 * returning failed devices.
1027 if (failed_devices
& (1 << role
))
1028 set_bit(Faulty
, &r
->flags
);
1035 static int super_validate(struct mddev
*mddev
, struct md_rdev
*rdev
)
1037 struct dm_raid_superblock
*sb
= page_address(rdev
->sb_page
);
1040 * If mddev->events is not set, we know we have not yet initialized
1043 if (!mddev
->events
&& super_init_validation(mddev
, rdev
))
1046 mddev
->bitmap_info
.offset
= 4096 >> 9; /* Enable bitmap creation */
1047 rdev
->mddev
->bitmap_info
.default_offset
= 4096 >> 9;
1048 if (!test_bit(FirstUse
, &rdev
->flags
)) {
1049 rdev
->recovery_offset
= le64_to_cpu(sb
->disk_recovery_offset
);
1050 if (rdev
->recovery_offset
!= MaxSector
)
1051 clear_bit(In_sync
, &rdev
->flags
);
1055 * If a device comes back, set it as not In_sync and no longer faulty.
1057 if (test_bit(Faulty
, &rdev
->flags
)) {
1058 clear_bit(Faulty
, &rdev
->flags
);
1059 clear_bit(In_sync
, &rdev
->flags
);
1060 rdev
->saved_raid_disk
= rdev
->raid_disk
;
1061 rdev
->recovery_offset
= 0;
1064 clear_bit(FirstUse
, &rdev
->flags
);
1070 * Analyse superblocks and select the freshest.
1072 static int analyse_superblocks(struct dm_target
*ti
, struct raid_set
*rs
)
1075 struct raid_dev
*dev
;
1076 struct md_rdev
*rdev
, *tmp
, *freshest
;
1077 struct mddev
*mddev
= &rs
->md
;
1080 rdev_for_each_safe(rdev
, tmp
, mddev
) {
1082 * Skipping super_load due to DMPF_SYNC will cause
1083 * the array to undergo initialization again as
1084 * though it were new. This is the intended effect
1085 * of the "sync" directive.
1087 * When reshaping capability is added, we must ensure
1088 * that the "sync" directive is disallowed during the
1091 if (rs
->print_flags
& DMPF_SYNC
)
1094 if (!rdev
->meta_bdev
)
1097 ret
= super_load(rdev
, freshest
);
1106 dev
= container_of(rdev
, struct raid_dev
, rdev
);
1108 dm_put_device(ti
, dev
->meta_dev
);
1110 dev
->meta_dev
= NULL
;
1111 rdev
->meta_bdev
= NULL
;
1114 put_page(rdev
->sb_page
);
1116 rdev
->sb_page
= NULL
;
1118 rdev
->sb_loaded
= 0;
1121 * We might be able to salvage the data device
1122 * even though the meta device has failed. For
1123 * now, we behave as though '- -' had been
1124 * set for this device in the table.
1127 dm_put_device(ti
, dev
->data_dev
);
1129 dev
->data_dev
= NULL
;
1132 list_del(&rdev
->same_set
);
1139 if (validate_raid_redundancy(rs
)) {
1140 rs
->ti
->error
= "Insufficient redundancy to activate array";
1145 * Validation of the freshest device provides the source of
1146 * validation for the remaining devices.
1148 ti
->error
= "Unable to assemble array: Invalid superblocks";
1149 if (super_validate(mddev
, freshest
))
1152 rdev_for_each(rdev
, mddev
)
1153 if ((rdev
!= freshest
) && super_validate(mddev
, rdev
))
1160 * Enable/disable discard support on RAID set depending on
1161 * RAID level and discard properties of underlying RAID members.
1163 static void configure_discard_support(struct dm_target
*ti
, struct raid_set
*rs
)
1168 /* Assume discards not supported until after checks below. */
1169 ti
->discards_supported
= false;
1171 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */
1172 raid456
= (rs
->md
.level
== 4 || rs
->md
.level
== 5 || rs
->md
.level
== 6);
1174 for (i
= 0; i
< rs
->md
.raid_disks
; i
++) {
1175 struct request_queue
*q
;
1177 if (!rs
->dev
[i
].rdev
.bdev
)
1180 q
= bdev_get_queue(rs
->dev
[i
].rdev
.bdev
);
1181 if (!q
|| !blk_queue_discard(q
))
1185 if (!q
->limits
.discard_zeroes_data
)
1187 if (!devices_handle_discard_safely
) {
1188 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
1189 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
1195 /* All RAID members properly support discards */
1196 ti
->discards_supported
= true;
1199 * RAID1 and RAID10 personalities require bio splitting,
1200 * RAID0/4/5/6 don't and process large discard bios properly.
1202 ti
->split_discard_bios
= !!(rs
->md
.level
== 1 || rs
->md
.level
== 10);
1203 ti
->num_discard_bios
= 1;
1207 * Construct a RAID4/5/6 mapping:
1209 * <raid_type> <#raid_params> <raid_params> \
1210 * <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> }
1212 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for
1213 * details on possible <raid_params>.
1215 static int raid_ctr(struct dm_target
*ti
, unsigned argc
, char **argv
)
1218 struct raid_type
*rt
;
1219 unsigned long num_raid_params
, num_raid_devs
;
1220 struct raid_set
*rs
= NULL
;
1222 /* Must have at least <raid_type> <#raid_params> */
1224 ti
->error
= "Too few arguments";
1229 rt
= get_raid_type(argv
[0]);
1231 ti
->error
= "Unrecognised raid_type";
1237 /* number of RAID parameters */
1238 if (kstrtoul(argv
[0], 10, &num_raid_params
) < 0) {
1239 ti
->error
= "Cannot understand number of RAID parameters";
1245 /* Skip over RAID params for now and find out # of devices */
1246 if (num_raid_params
+ 1 > argc
) {
1247 ti
->error
= "Arguments do not agree with counts given";
1251 if ((kstrtoul(argv
[num_raid_params
], 10, &num_raid_devs
) < 0) ||
1252 (num_raid_devs
>= INT_MAX
)) {
1253 ti
->error
= "Cannot understand number of raid devices";
1257 rs
= context_alloc(ti
, rt
, (unsigned)num_raid_devs
);
1261 ret
= parse_raid_params(rs
, argv
, (unsigned)num_raid_params
);
1267 argc
-= num_raid_params
+ 1; /* +1: we already have num_raid_devs */
1268 argv
+= num_raid_params
+ 1;
1270 if (argc
!= (num_raid_devs
* 2)) {
1271 ti
->error
= "Supplied RAID devices does not match the count given";
1275 ret
= dev_parms(rs
, argv
);
1279 rs
->md
.sync_super
= super_sync
;
1280 ret
= analyse_superblocks(ti
, rs
);
1284 INIT_WORK(&rs
->md
.event_work
, do_table_event
);
1286 ti
->num_flush_bios
= 1;
1289 * Disable/enable discard support on RAID set.
1291 configure_discard_support(ti
, rs
);
1293 mutex_lock(&rs
->md
.reconfig_mutex
);
1294 ret
= md_run(&rs
->md
);
1295 rs
->md
.in_sync
= 0; /* Assume already marked dirty */
1296 mutex_unlock(&rs
->md
.reconfig_mutex
);
1299 ti
->error
= "Fail to run raid array";
1303 if (ti
->len
!= rs
->md
.array_sectors
) {
1304 ti
->error
= "Array size does not match requested target length";
1308 rs
->callbacks
.congested_fn
= raid_is_congested
;
1309 dm_table_add_target_callbacks(ti
->table
, &rs
->callbacks
);
1311 mddev_suspend(&rs
->md
);
1322 static void raid_dtr(struct dm_target
*ti
)
1324 struct raid_set
*rs
= ti
->private;
1326 list_del_init(&rs
->callbacks
.list
);
1331 static int raid_map(struct dm_target
*ti
, struct bio
*bio
)
1333 struct raid_set
*rs
= ti
->private;
1334 struct mddev
*mddev
= &rs
->md
;
1336 mddev
->pers
->make_request(mddev
, bio
);
1338 return DM_MAPIO_SUBMITTED
;
1341 static const char *decipher_sync_action(struct mddev
*mddev
)
1343 if (test_bit(MD_RECOVERY_FROZEN
, &mddev
->recovery
))
1346 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
) ||
1347 (!mddev
->ro
&& test_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
))) {
1348 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
1351 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
1352 if (!test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
1354 else if (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
))
1359 if (test_bit(MD_RECOVERY_RECOVER
, &mddev
->recovery
))
1366 static void raid_status(struct dm_target
*ti
, status_type_t type
,
1367 unsigned status_flags
, char *result
, unsigned maxlen
)
1369 struct raid_set
*rs
= ti
->private;
1370 unsigned raid_param_cnt
= 1; /* at least 1 for chunksize */
1372 int i
, array_in_sync
= 0;
1376 case STATUSTYPE_INFO
:
1377 DMEMIT("%s %d ", rs
->raid_type
->name
, rs
->md
.raid_disks
);
1379 if (test_bit(MD_RECOVERY_RUNNING
, &rs
->md
.recovery
))
1380 sync
= rs
->md
.curr_resync_completed
;
1382 sync
= rs
->md
.recovery_cp
;
1384 if (sync
>= rs
->md
.resync_max_sectors
) {
1389 sync
= rs
->md
.resync_max_sectors
;
1390 } else if (test_bit(MD_RECOVERY_REQUESTED
, &rs
->md
.recovery
)) {
1392 * If "check" or "repair" is occurring, the array has
1393 * undergone and initial sync and the health characters
1394 * should not be 'a' anymore.
1399 * The array may be doing an initial sync, or it may
1400 * be rebuilding individual components. If all the
1401 * devices are In_sync, then it is the array that is
1402 * being initialized.
1404 for (i
= 0; i
< rs
->md
.raid_disks
; i
++)
1405 if (!test_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
))
1410 * Status characters:
1411 * 'D' = Dead/Failed device
1412 * 'a' = Alive but not in-sync
1413 * 'A' = Alive and in-sync
1415 for (i
= 0; i
< rs
->md
.raid_disks
; i
++) {
1416 if (test_bit(Faulty
, &rs
->dev
[i
].rdev
.flags
))
1418 else if (!array_in_sync
||
1419 !test_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
))
1427 * The in-sync ratio shows the progress of:
1428 * - Initializing the array
1429 * - Rebuilding a subset of devices of the array
1430 * The user can distinguish between the two by referring
1431 * to the status characters.
1433 DMEMIT(" %llu/%llu",
1434 (unsigned long long) sync
,
1435 (unsigned long long) rs
->md
.resync_max_sectors
);
1439 * See Documentation/device-mapper/dm-raid.c for
1440 * information on each of these states.
1442 DMEMIT(" %s", decipher_sync_action(&rs
->md
));
1445 * resync_mismatches/mismatch_cnt
1446 * This field shows the number of discrepancies found when
1447 * performing a "check" of the array.
1450 (strcmp(rs
->md
.last_sync_action
, "check")) ? 0 :
1451 (unsigned long long)
1452 atomic64_read(&rs
->md
.resync_mismatches
));
1454 case STATUSTYPE_TABLE
:
1455 /* The string you would use to construct this array */
1456 for (i
= 0; i
< rs
->md
.raid_disks
; i
++) {
1457 if ((rs
->print_flags
& DMPF_REBUILD
) &&
1458 rs
->dev
[i
].data_dev
&&
1459 !test_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
))
1460 raid_param_cnt
+= 2; /* for rebuilds */
1461 if (rs
->dev
[i
].data_dev
&&
1462 test_bit(WriteMostly
, &rs
->dev
[i
].rdev
.flags
))
1463 raid_param_cnt
+= 2;
1466 raid_param_cnt
+= (hweight32(rs
->print_flags
& ~DMPF_REBUILD
) * 2);
1467 if (rs
->print_flags
& (DMPF_SYNC
| DMPF_NOSYNC
))
1470 DMEMIT("%s %u %u", rs
->raid_type
->name
,
1471 raid_param_cnt
, rs
->md
.chunk_sectors
);
1473 if ((rs
->print_flags
& DMPF_SYNC
) &&
1474 (rs
->md
.recovery_cp
== MaxSector
))
1476 if (rs
->print_flags
& DMPF_NOSYNC
)
1479 for (i
= 0; i
< rs
->md
.raid_disks
; i
++)
1480 if ((rs
->print_flags
& DMPF_REBUILD
) &&
1481 rs
->dev
[i
].data_dev
&&
1482 !test_bit(In_sync
, &rs
->dev
[i
].rdev
.flags
))
1483 DMEMIT(" rebuild %u", i
);
1485 if (rs
->print_flags
& DMPF_DAEMON_SLEEP
)
1486 DMEMIT(" daemon_sleep %lu",
1487 rs
->md
.bitmap_info
.daemon_sleep
);
1489 if (rs
->print_flags
& DMPF_MIN_RECOVERY_RATE
)
1490 DMEMIT(" min_recovery_rate %d", rs
->md
.sync_speed_min
);
1492 if (rs
->print_flags
& DMPF_MAX_RECOVERY_RATE
)
1493 DMEMIT(" max_recovery_rate %d", rs
->md
.sync_speed_max
);
1495 for (i
= 0; i
< rs
->md
.raid_disks
; i
++)
1496 if (rs
->dev
[i
].data_dev
&&
1497 test_bit(WriteMostly
, &rs
->dev
[i
].rdev
.flags
))
1498 DMEMIT(" write_mostly %u", i
);
1500 if (rs
->print_flags
& DMPF_MAX_WRITE_BEHIND
)
1501 DMEMIT(" max_write_behind %lu",
1502 rs
->md
.bitmap_info
.max_write_behind
);
1504 if (rs
->print_flags
& DMPF_STRIPE_CACHE
) {
1505 struct r5conf
*conf
= rs
->md
.private;
1507 /* convert from kiB to sectors */
1508 DMEMIT(" stripe_cache %d",
1509 conf
? conf
->max_nr_stripes
* 2 : 0);
1512 if (rs
->print_flags
& DMPF_REGION_SIZE
)
1513 DMEMIT(" region_size %lu",
1514 rs
->md
.bitmap_info
.chunksize
>> 9);
1516 if (rs
->print_flags
& DMPF_RAID10_COPIES
)
1517 DMEMIT(" raid10_copies %u",
1518 raid10_md_layout_to_copies(rs
->md
.layout
));
1520 if (rs
->print_flags
& DMPF_RAID10_FORMAT
)
1521 DMEMIT(" raid10_format %s",
1522 raid10_md_layout_to_format(rs
->md
.layout
));
1524 DMEMIT(" %d", rs
->md
.raid_disks
);
1525 for (i
= 0; i
< rs
->md
.raid_disks
; i
++) {
1526 if (rs
->dev
[i
].meta_dev
)
1527 DMEMIT(" %s", rs
->dev
[i
].meta_dev
->name
);
1531 if (rs
->dev
[i
].data_dev
)
1532 DMEMIT(" %s", rs
->dev
[i
].data_dev
->name
);
1539 static int raid_message(struct dm_target
*ti
, unsigned argc
, char **argv
)
1541 struct raid_set
*rs
= ti
->private;
1542 struct mddev
*mddev
= &rs
->md
;
1544 if (!strcasecmp(argv
[0], "reshape")) {
1545 DMERR("Reshape not supported.");
1549 if (!mddev
->pers
|| !mddev
->pers
->sync_request
)
1552 if (!strcasecmp(argv
[0], "frozen"))
1553 set_bit(MD_RECOVERY_FROZEN
, &mddev
->recovery
);
1555 clear_bit(MD_RECOVERY_FROZEN
, &mddev
->recovery
);
1557 if (!strcasecmp(argv
[0], "idle") || !strcasecmp(argv
[0], "frozen")) {
1558 if (mddev
->sync_thread
) {
1559 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1560 md_reap_sync_thread(mddev
);
1562 } else if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
) ||
1563 test_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
))
1565 else if (!strcasecmp(argv
[0], "resync"))
1566 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
1567 else if (!strcasecmp(argv
[0], "recover")) {
1568 set_bit(MD_RECOVERY_RECOVER
, &mddev
->recovery
);
1569 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
1571 if (!strcasecmp(argv
[0], "check"))
1572 set_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
1573 else if (!!strcasecmp(argv
[0], "repair"))
1575 set_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
);
1576 set_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
1578 if (mddev
->ro
== 2) {
1579 /* A write to sync_action is enough to justify
1580 * canceling read-auto mode
1583 if (!mddev
->suspended
)
1584 md_wakeup_thread(mddev
->sync_thread
);
1586 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
1587 if (!mddev
->suspended
)
1588 md_wakeup_thread(mddev
->thread
);
1593 static int raid_iterate_devices(struct dm_target
*ti
,
1594 iterate_devices_callout_fn fn
, void *data
)
1596 struct raid_set
*rs
= ti
->private;
1600 for (i
= 0; !ret
&& i
< rs
->md
.raid_disks
; i
++)
1601 if (rs
->dev
[i
].data_dev
)
1603 rs
->dev
[i
].data_dev
,
1604 0, /* No offset on data devs */
1611 static void raid_io_hints(struct dm_target
*ti
, struct queue_limits
*limits
)
1613 struct raid_set
*rs
= ti
->private;
1614 unsigned chunk_size
= rs
->md
.chunk_sectors
<< 9;
1615 struct r5conf
*conf
= rs
->md
.private;
1617 blk_limits_io_min(limits
, chunk_size
);
1618 blk_limits_io_opt(limits
, chunk_size
* (conf
->raid_disks
- conf
->max_degraded
));
1621 static void raid_presuspend(struct dm_target
*ti
)
1623 struct raid_set
*rs
= ti
->private;
1625 md_stop_writes(&rs
->md
);
1628 static void raid_postsuspend(struct dm_target
*ti
)
1630 struct raid_set
*rs
= ti
->private;
1632 mddev_suspend(&rs
->md
);
1635 static void attempt_restore_of_faulty_devices(struct raid_set
*rs
)
1638 uint64_t failed_devices
, cleared_failed_devices
= 0;
1639 unsigned long flags
;
1640 struct dm_raid_superblock
*sb
;
1643 for (i
= 0; i
< rs
->md
.raid_disks
; i
++) {
1644 r
= &rs
->dev
[i
].rdev
;
1645 if (test_bit(Faulty
, &r
->flags
) && r
->sb_page
&&
1646 sync_page_io(r
, 0, r
->sb_size
, r
->sb_page
, READ
, 1)) {
1647 DMINFO("Faulty %s device #%d has readable super block."
1648 " Attempting to revive it.",
1649 rs
->raid_type
->name
, i
);
1652 * Faulty bit may be set, but sometimes the array can
1653 * be suspended before the personalities can respond
1654 * by removing the device from the array (i.e. calling
1655 * 'hot_remove_disk'). If they haven't yet removed
1656 * the failed device, its 'raid_disk' number will be
1657 * '>= 0' - meaning we must call this function
1660 if ((r
->raid_disk
>= 0) &&
1661 (r
->mddev
->pers
->hot_remove_disk(r
->mddev
, r
) != 0))
1662 /* Failed to revive this device, try next */
1666 r
->saved_raid_disk
= i
;
1668 clear_bit(Faulty
, &r
->flags
);
1669 clear_bit(WriteErrorSeen
, &r
->flags
);
1670 clear_bit(In_sync
, &r
->flags
);
1671 if (r
->mddev
->pers
->hot_add_disk(r
->mddev
, r
)) {
1673 r
->saved_raid_disk
= -1;
1676 r
->recovery_offset
= 0;
1677 cleared_failed_devices
|= 1 << i
;
1681 if (cleared_failed_devices
) {
1682 rdev_for_each(r
, &rs
->md
) {
1683 sb
= page_address(r
->sb_page
);
1684 failed_devices
= le64_to_cpu(sb
->failed_devices
);
1685 failed_devices
&= ~cleared_failed_devices
;
1686 sb
->failed_devices
= cpu_to_le64(failed_devices
);
1691 static void raid_resume(struct dm_target
*ti
)
1693 struct raid_set
*rs
= ti
->private;
1695 set_bit(MD_CHANGE_DEVS
, &rs
->md
.flags
);
1696 if (!rs
->bitmap_loaded
) {
1697 bitmap_load(&rs
->md
);
1698 rs
->bitmap_loaded
= 1;
1701 * A secondary resume while the device is active.
1702 * Take this opportunity to check whether any failed
1703 * devices are reachable again.
1705 attempt_restore_of_faulty_devices(rs
);
1708 clear_bit(MD_RECOVERY_FROZEN
, &rs
->md
.recovery
);
1709 mddev_resume(&rs
->md
);
1712 static struct target_type raid_target
= {
1714 .version
= {1, 6, 0},
1715 .module
= THIS_MODULE
,
1719 .status
= raid_status
,
1720 .message
= raid_message
,
1721 .iterate_devices
= raid_iterate_devices
,
1722 .io_hints
= raid_io_hints
,
1723 .presuspend
= raid_presuspend
,
1724 .postsuspend
= raid_postsuspend
,
1725 .resume
= raid_resume
,
1728 static int __init
dm_raid_init(void)
1730 DMINFO("Loading target version %u.%u.%u",
1731 raid_target
.version
[0],
1732 raid_target
.version
[1],
1733 raid_target
.version
[2]);
1734 return dm_register_target(&raid_target
);
1737 static void __exit
dm_raid_exit(void)
1739 dm_unregister_target(&raid_target
);
1742 module_init(dm_raid_init
);
1743 module_exit(dm_raid_exit
);
1745 module_param(devices_handle_discard_safely
, bool, 0644);
1746 MODULE_PARM_DESC(devices_handle_discard_safely
,
1747 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
1749 MODULE_DESCRIPTION(DM_NAME
" raid4/5/6 target");
1750 MODULE_ALIAS("dm-raid1");
1751 MODULE_ALIAS("dm-raid10");
1752 MODULE_ALIAS("dm-raid4");
1753 MODULE_ALIAS("dm-raid5");
1754 MODULE_ALIAS("dm-raid6");
1755 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
1756 MODULE_LICENSE("GPL");