linux_dsm_epyc7002/drivers/md/dm-raid.c
Heinz Mauelshagen a30cbc0d1c dm raid: inverse check for flags from invalid to valid flags
It is more intuitive to manage each raid level's features in terms of
what is supported rather than what isn't supported.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-06-14 17:25:02 -04:00

2930 lines
84 KiB
C

/*
* Copyright (C) 2010-2011 Neil Brown
* Copyright (C) 2010-2016 Red Hat, Inc. All rights reserved.
*
* This file is released under the GPL.
*/
#include <linux/slab.h>
#include <linux/module.h>
#include "md.h"
#include "raid1.h"
#include "raid5.h"
#include "raid10.h"
#include "bitmap.h"
#include <linux/device-mapper.h>
#define DM_MSG_PREFIX "raid"
#define MAX_RAID_DEVICES 253 /* md-raid kernel limit */
static bool devices_handle_discard_safely = false;
/*
* The following flags are used by dm-raid.c to set up the array state.
* They must be cleared before md_run is called.
*/
#define FirstUse 10 /* rdev flag */
struct raid_dev {
/*
* Two DM devices, one to hold metadata and one to hold the
* actual data/parity. The reason for this is to not confuse
* ti->len and give more flexibility in altering size and
* characteristics.
*
* While it is possible for this device to be associated
* with a different physical device than the data_dev, it
* is intended for it to be the same.
* |--------- Physical Device ---------|
* |- meta_dev -|------ data_dev ------|
*/
struct dm_dev *meta_dev;
struct dm_dev *data_dev;
struct md_rdev rdev;
};
/*
* Bits for establishing rs->ctr_flags
*
* 1 = no flag value
* 2 = flag with value
*/
#define __CTR_FLAG_SYNC 0 /* 1 */ /* Not with raid0! */
#define __CTR_FLAG_NOSYNC 1 /* 1 */ /* Not with raid0! */
#define __CTR_FLAG_REBUILD 2 /* 2 */ /* Not with raid0! */
#define __CTR_FLAG_DAEMON_SLEEP 3 /* 2 */ /* Not with raid0! */
#define __CTR_FLAG_MIN_RECOVERY_RATE 4 /* 2 */ /* Not with raid0! */
#define __CTR_FLAG_MAX_RECOVERY_RATE 5 /* 2 */ /* Not with raid0! */
#define __CTR_FLAG_MAX_WRITE_BEHIND 6 /* 2 */ /* Only with raid1! */
#define __CTR_FLAG_WRITE_MOSTLY 7 /* 2 */ /* Only with raid1! */
#define __CTR_FLAG_STRIPE_CACHE 8 /* 2 */ /* Only with raid4/5/6! */
#define __CTR_FLAG_REGION_SIZE 9 /* 2 */ /* Not with raid0! */
#define __CTR_FLAG_RAID10_COPIES 10 /* 2 */ /* Only with raid10 */
#define __CTR_FLAG_RAID10_FORMAT 11 /* 2 */ /* Only with raid10 */
/* New for v1.9.0 */
#define __CTR_FLAG_DELTA_DISKS 12 /* 2 */ /* Only with reshapable raid4/5/6/10! */
#define __CTR_FLAG_DATA_OFFSET 13 /* 2 */ /* Only with reshapable raid4/5/6/10! */
#define __CTR_FLAG_RAID10_USE_NEAR_SETS 14 /* 2 */ /* Only with raid10! */
/*
* Flags for rs->ctr_flags field.
*/
#define CTR_FLAG_SYNC (1 << __CTR_FLAG_SYNC)
#define CTR_FLAG_NOSYNC (1 << __CTR_FLAG_NOSYNC)
#define CTR_FLAG_REBUILD (1 << __CTR_FLAG_REBUILD)
#define CTR_FLAG_DAEMON_SLEEP (1 << __CTR_FLAG_DAEMON_SLEEP)
#define CTR_FLAG_MIN_RECOVERY_RATE (1 << __CTR_FLAG_MIN_RECOVERY_RATE)
#define CTR_FLAG_MAX_RECOVERY_RATE (1 << __CTR_FLAG_MAX_RECOVERY_RATE)
#define CTR_FLAG_MAX_WRITE_BEHIND (1 << __CTR_FLAG_MAX_WRITE_BEHIND)
#define CTR_FLAG_WRITE_MOSTLY (1 << __CTR_FLAG_WRITE_MOSTLY)
#define CTR_FLAG_STRIPE_CACHE (1 << __CTR_FLAG_STRIPE_CACHE)
#define CTR_FLAG_REGION_SIZE (1 << __CTR_FLAG_REGION_SIZE)
#define CTR_FLAG_RAID10_COPIES (1 << __CTR_FLAG_RAID10_COPIES)
#define CTR_FLAG_RAID10_FORMAT (1 << __CTR_FLAG_RAID10_FORMAT)
#define CTR_FLAG_DELTA_DISKS (1 << __CTR_FLAG_DELTA_DISKS)
#define CTR_FLAG_DATA_OFFSET (1 << __CTR_FLAG_DATA_OFFSET)
#define CTR_FLAG_RAID10_USE_NEAR_SETS (1 << __CTR_FLAG_RAID10_USE_NEAR_SETS)
/*
* Definitions of various constructor flags to
* be used in checks of valid / invalid flags
* per raid level.
*/
/* Define all any sync flags */
#define CTR_FLAGS_ANY_SYNC (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)
/* Define flags for options without argument (e.g. 'nosync') */
#define CTR_FLAG_OPTIONS_NO_ARGS (CTR_FLAGS_ANY_SYNC | \
CTR_FLAG_RAID10_USE_NEAR_SETS)
/* Define flags for options with one argument (e.g. 'delta_disks +2') */
#define CTR_FLAG_OPTIONS_ONE_ARG (CTR_FLAG_REBUILD | \
CTR_FLAG_WRITE_MOSTLY | \
CTR_FLAG_DAEMON_SLEEP | \
CTR_FLAG_MIN_RECOVERY_RATE | \
CTR_FLAG_MAX_RECOVERY_RATE | \
CTR_FLAG_MAX_WRITE_BEHIND | \
CTR_FLAG_STRIPE_CACHE | \
CTR_FLAG_REGION_SIZE | \
CTR_FLAG_RAID10_COPIES | \
CTR_FLAG_RAID10_FORMAT | \
CTR_FLAG_DELTA_DISKS | \
CTR_FLAG_DATA_OFFSET)
/* Valid options definitions per raid level... */
/* "raid0" does only accept data offset */
#define RAID0_VALID_FLAGS (CTR_FLAG_DATA_OFFSET)
/* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */
#define RAID1_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
CTR_FLAG_REBUILD | \
CTR_FLAG_WRITE_MOSTLY | \
CTR_FLAG_DAEMON_SLEEP | \
CTR_FLAG_MIN_RECOVERY_RATE | \
CTR_FLAG_MAX_RECOVERY_RATE | \
CTR_FLAG_MAX_WRITE_BEHIND | \
CTR_FLAG_REGION_SIZE | \
CTR_FLAG_DATA_OFFSET)
/* "raid10" does not accept any raid1 or stripe cache options */
#define RAID10_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
CTR_FLAG_REBUILD | \
CTR_FLAG_DAEMON_SLEEP | \
CTR_FLAG_MIN_RECOVERY_RATE | \
CTR_FLAG_MAX_RECOVERY_RATE | \
CTR_FLAG_REGION_SIZE | \
CTR_FLAG_RAID10_COPIES | \
CTR_FLAG_RAID10_FORMAT | \
CTR_FLAG_DELTA_DISKS | \
CTR_FLAG_DATA_OFFSET | \
CTR_FLAG_RAID10_USE_NEAR_SETS)
/*
* "raid4/5/6" do not accept any raid1 or raid10 specific options
*
* "raid6" does not accept "nosync", because it is not guaranteed
* that both parity and q-syndrome are being written properly with
* any writes
*/
#define RAID45_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \
CTR_FLAG_REBUILD | \
CTR_FLAG_DAEMON_SLEEP | \
CTR_FLAG_MIN_RECOVERY_RATE | \
CTR_FLAG_MAX_RECOVERY_RATE | \
CTR_FLAG_MAX_WRITE_BEHIND | \
CTR_FLAG_STRIPE_CACHE | \
CTR_FLAG_REGION_SIZE | \
CTR_FLAG_DELTA_DISKS | \
CTR_FLAG_DATA_OFFSET)
#define RAID6_VALID_FLAGS (CTR_FLAG_SYNC | \
CTR_FLAG_REBUILD | \
CTR_FLAG_DAEMON_SLEEP | \
CTR_FLAG_MIN_RECOVERY_RATE | \
CTR_FLAG_MAX_RECOVERY_RATE | \
CTR_FLAG_MAX_WRITE_BEHIND | \
CTR_FLAG_STRIPE_CACHE | \
CTR_FLAG_REGION_SIZE | \
CTR_FLAG_DELTA_DISKS | \
CTR_FLAG_DATA_OFFSET)
/* ...valid options definitions per raid level */
/*
* Flags for rs->runtime_flags field
* (RT_FLAG prefix meaning "runtime flag")
*
* These are all internal and used to define runtime state,
* e.g. to prevent another resume from preresume processing
* the raid set all over again.
*/
#define RT_FLAG_RS_PRERESUMED 0x1
#define RT_FLAG_RS_RESUMED 0x2
#define RT_FLAG_RS_BITMAP_LOADED 0x4
#define RT_FLAG_UPDATE_SBS 0x8
/* Array elements of 64 bit needed for rebuild/write_mostly bits */
#define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
/*
* raid set level, layout and chunk sectors backup/restore
*/
struct rs_layout {
int new_level;
int new_layout;
int new_chunk_sectors;
};
struct raid_set {
struct dm_target *ti;
uint32_t bitmap_loaded;
unsigned long ctr_flags;
unsigned long runtime_flags;
uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
int raid_disks;
int delta_disks;
int data_offset;
int raid10_copies;
struct mddev md;
struct raid_type *raid_type;
struct dm_target_callbacks callbacks;
struct rs_layout rs_layout;
struct raid_dev dev[0];
};
static void rs_config_backup(struct raid_set *rs)
{
struct mddev *mddev = &rs->md;
struct rs_layout *l = &rs->rs_layout;
l->new_level = mddev->new_level;
l->new_layout = mddev->new_layout;
l->new_chunk_sectors = mddev->new_chunk_sectors;
}
static void rs_config_restore(struct raid_set *rs)
{
struct mddev *mddev = &rs->md;
struct rs_layout *l = &rs->rs_layout;
mddev->new_level = l->new_level;
mddev->new_layout = l->new_layout;
mddev->new_chunk_sectors = l->new_chunk_sectors;
}
/* raid10 algorithms (i.e. formats) */
#define ALGORITHM_RAID10_DEFAULT 0
#define ALGORITHM_RAID10_NEAR 1
#define ALGORITHM_RAID10_OFFSET 2
#define ALGORITHM_RAID10_FAR 3
/* Supported raid types and properties. */
static struct raid_type {
const char *name; /* RAID algorithm. */
const char *descr; /* Descriptor text for logging. */
const unsigned parity_devs; /* # of parity devices. */
const unsigned minimal_devs; /* minimal # of devices in set. */
const unsigned level; /* RAID level. */
const unsigned algorithm; /* RAID algorithm. */
} raid_types[] = {
{"raid0", "raid0 (striping)", 0, 2, 0, 0 /* NONE */},
{"raid1", "raid1 (mirroring)", 0, 2, 1, 0 /* NONE */},
{"raid10_far", "raid10 far (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_FAR},
{"raid10_offset", "raid10 offset (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_OFFSET},
{"raid10_near", "raid10 near (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_NEAR},
{"raid10", "raid10 (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_DEFAULT},
{"raid4", "raid4 (dedicated last parity disk)", 1, 2, 4, ALGORITHM_PARITY_N}, /* raid4 layout = raid5_n */
{"raid5_n", "raid5 (dedicated last parity disk)", 1, 2, 5, ALGORITHM_PARITY_N},
{"raid5_ls", "raid5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC},
{"raid5_rs", "raid5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC},
{"raid5_la", "raid5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC},
{"raid5_ra", "raid5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC},
{"raid6_zr", "raid6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART},
{"raid6_nr", "raid6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART},
{"raid6_nc", "raid6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE},
{"raid6_n_6", "raid6 (dedicated parity/Q n/6)", 2, 4, 6, ALGORITHM_PARITY_N_6},
{"raid6_ls_6", "raid6 (left symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_SYMMETRIC_6},
{"raid6_rs_6", "raid6 (right symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_SYMMETRIC_6},
{"raid6_la_6", "raid6 (left asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_ASYMMETRIC_6},
{"raid6_ra_6", "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_ASYMMETRIC_6}
};
/* True, if @v is in inclusive range [@min, @max] */
static bool __within_range(long v, long min, long max)
{
return v >= min && v <= max;
}
/* All table line arguments are defined here */
static struct arg_name_flag {
const unsigned long flag;
const char *name;
} __arg_name_flags[] = {
{ CTR_FLAG_SYNC, "sync"},
{ CTR_FLAG_NOSYNC, "nosync"},
{ CTR_FLAG_REBUILD, "rebuild"},
{ CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
{ CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
{ CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
{ CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
{ CTR_FLAG_WRITE_MOSTLY, "writemostly"},
{ CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
{ CTR_FLAG_REGION_SIZE, "region_size"},
{ CTR_FLAG_RAID10_COPIES, "raid10_copies"},
{ CTR_FLAG_RAID10_FORMAT, "raid10_format"},
{ CTR_FLAG_DATA_OFFSET, "data_offset"},
{ CTR_FLAG_DELTA_DISKS, "delta_disks"},
{ CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
};
/* Return argument name string for given @flag */
static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
{
if (hweight32(flag) == 1) {
struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
while (anf-- > __arg_name_flags)
if (flag & anf->flag)
return anf->name;
} else
DMERR("%s called with more than one flag!", __func__);
return NULL;
}
/*
* bool helpers to test for various raid levels of a raid set,
* is. it's level as reported by the superblock rather than
* the requested raid_type passed to the constructor.
*/
/* Return true, if raid set in @rs is raid0 */
static bool rs_is_raid0(struct raid_set *rs)
{
return !rs->md.level;
}
/* Return true, if raid set in @rs is raid10 */
static bool rs_is_raid10(struct raid_set *rs)
{
return rs->md.level == 10;
}
/*
* bool helpers to test for various raid levels of a raid type
*/
/* Return true, if raid type in @rt is raid0 */
static bool rt_is_raid0(struct raid_type *rt)
{
return !rt->level;
}
/* Return true, if raid type in @rt is raid1 */
static bool rt_is_raid1(struct raid_type *rt)
{
return rt->level == 1;
}
/* Return true, if raid type in @rt is raid10 */
static bool rt_is_raid10(struct raid_type *rt)
{
return rt->level == 10;
}
/* Return true, if raid type in @rt is raid4/5 */
static bool rt_is_raid45(struct raid_type *rt)
{
return __within_range(rt->level, 4, 5);
}
/* Return true, if raid type in @rt is raid6 */
static bool rt_is_raid6(struct raid_type *rt)
{
return rt->level == 6;
}
/* Return true, if raid type in @rt is raid4/5/6 */
static bool rt_is_raid456(struct raid_type *rt)
{
return __within_range(rt->level, 4, 6);
}
/* END: raid level bools */
/* Return valid ctr flags for the raid level of @rs */
static unsigned long __valid_flags(struct raid_set *rs)
{
if (rt_is_raid0(rs->raid_type))
return RAID0_VALID_FLAGS;
else if (rt_is_raid1(rs->raid_type))
return RAID1_VALID_FLAGS;
else if (rt_is_raid10(rs->raid_type))
return RAID10_VALID_FLAGS;
else if (rt_is_raid45(rs->raid_type))
return RAID45_VALID_FLAGS;
else if (rt_is_raid6(rs->raid_type))
return RAID6_VALID_FLAGS;
return ~0;
}
/*
* Check for valid flags set on @rs
*
* Has to be called after parsing of the ctr flags!
*/
static int rs_check_for_valid_flags(struct raid_set *rs)
{
if (rs->ctr_flags & ~__valid_flags(rs)) {
rs->ti->error = "Invalid flags combination";
return -EINVAL;
}
return 0;
}
/* MD raid10 bit definitions and helpers */
#define RAID10_OFFSET (1 << 16) /* stripes with data copies area adjacent on devices */
#define RAID10_BROCKEN_USE_FAR_SETS (1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
#define RAID10_USE_FAR_SETS (1 << 18) /* Use sets instead of whole stripe rotation */
#define RAID10_FAR_COPIES_SHIFT 8 /* raid10 # far copies shift (2nd byte of layout) */
/* Return md raid10 near copies for @layout */
static unsigned int __raid10_near_copies(int layout)
{
return layout & 0xFF;
}
/* Return md raid10 far copies for @layout */
static unsigned int __raid10_far_copies(int layout)
{
return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
}
/* Return true if md raid10 offset for @layout */
static unsigned int __is_raid10_offset(int layout)
{
return layout & RAID10_OFFSET;
}
/* Return true if md raid10 near for @layout */
static unsigned int __is_raid10_near(int layout)
{
return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
}
/* Return true if md raid10 far for @layout */
static unsigned int __is_raid10_far(int layout)
{
return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
}
/* Return md raid10 layout string for @layout */
static const char *raid10_md_layout_to_format(int layout)
{
/*
* Bit 16 stands for "offset"
* (i.e. adjacent stripes hold copies)
*
* Refer to MD's raid10.c for details
*/
if (__is_raid10_offset(layout))
return "offset";
if (__raid10_near_copies(layout) > 1)
return "near";
WARN_ON(__raid10_far_copies(layout) < 2);
return "far";
}
/* Return md raid10 algorithm for @name */
static const int raid10_name_to_format(const char *name)
{
if (!strcasecmp(name, "near"))
return ALGORITHM_RAID10_NEAR;
else if (!strcasecmp(name, "offset"))
return ALGORITHM_RAID10_OFFSET;
else if (!strcasecmp(name, "far"))
return ALGORITHM_RAID10_FAR;
return -EINVAL;
}
/* Return md raid10 copies for @layout */
static unsigned int raid10_md_layout_to_copies(int layout)
{
return __raid10_near_copies(layout) > 1 ?
__raid10_near_copies(layout) : __raid10_far_copies(layout);
}
/* Return md raid10 format id for @format string */
static int raid10_format_to_md_layout(struct raid_set *rs,
unsigned int algorithm,
unsigned int copies)
{
unsigned int n = 1, f = 1, r = 0;
/*
* MD resilienece flaw:
*
* enabling use_far_sets for far/offset formats causes copies
* to be colocated on the same devs together with their origins!
*
* -> disable it for now in the definition above
*/
if (algorithm == ALGORITHM_RAID10_DEFAULT ||
algorithm == ALGORITHM_RAID10_NEAR)
n = copies;
else if (algorithm == ALGORITHM_RAID10_OFFSET) {
f = copies;
r = RAID10_OFFSET;
if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
r |= RAID10_USE_FAR_SETS;
} else if (algorithm == ALGORITHM_RAID10_FAR) {
f = copies;
r = !RAID10_OFFSET;
if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
r |= RAID10_USE_FAR_SETS;
} else
return -EINVAL;
return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
}
/* END: MD raid10 bit definitions and helpers */
/* Check for any of the raid10 algorithms */
static int __got_raid10(struct raid_type *rtp, const int layout)
{
if (rtp->level == 10) {
switch (rtp->algorithm) {
case ALGORITHM_RAID10_DEFAULT:
case ALGORITHM_RAID10_NEAR:
return __is_raid10_near(layout);
case ALGORITHM_RAID10_OFFSET:
return __is_raid10_offset(layout);
case ALGORITHM_RAID10_FAR:
return __is_raid10_far(layout);
default:
break;
}
}
return 0;
}
/* Return raid_type for @name */
static struct raid_type *get_raid_type(const char *name)
{
struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
while (rtp-- > raid_types)
if (!strcasecmp(rtp->name, name))
return rtp;
return NULL;
}
/* Return raid_type for @name based derived from @level and @layout */
static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
{
struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
while (rtp-- > raid_types) {
/* RAID10 special checks based on @layout flags/properties */
if (rtp->level == level &&
(__got_raid10(rtp, layout) || rtp->algorithm == layout))
return rtp;
}
return NULL;
}
/*
* Set the mddev properties in @rs to the current
* ones retrieved from the freshest superblock
*/
static void rs_set_cur(struct raid_set *rs)
{
struct mddev *mddev = &rs->md;
mddev->new_level = mddev->level;
mddev->new_layout = mddev->layout;
mddev->new_chunk_sectors = mddev->chunk_sectors;
}
/*
* Set the mddev properties in @rs to the new
* ones requested by the ctr
*/
static void rs_set_new(struct raid_set *rs)
{
struct mddev *mddev = &rs->md;
mddev->level = mddev->new_level;
mddev->layout = mddev->new_layout;
mddev->chunk_sectors = mddev->new_chunk_sectors;
mddev->raid_disks = rs->raid_disks;
mddev->delta_disks = 0;
}
static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
unsigned raid_devs)
{
unsigned i;
struct raid_set *rs;
if (raid_devs <= raid_type->parity_devs) {
ti->error = "Insufficient number of devices";
return ERR_PTR(-EINVAL);
}
rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL);
if (!rs) {
ti->error = "Cannot allocate raid context";
return ERR_PTR(-ENOMEM);
}
mddev_init(&rs->md);
rs->raid_disks = raid_devs;
rs->delta_disks = 0;
rs->ti = ti;
rs->raid_type = raid_type;
rs->md.raid_disks = raid_devs;
rs->md.level = raid_type->level;
rs->md.new_level = rs->md.level;
rs->md.layout = raid_type->algorithm;
rs->md.new_layout = rs->md.layout;
rs->md.delta_disks = 0;
rs->md.recovery_cp = rs_is_raid0(rs) ? MaxSector : 0;
for (i = 0; i < raid_devs; i++)
md_rdev_init(&rs->dev[i].rdev);
/*
* Remaining items to be initialized by further RAID params:
* rs->md.persistent
* rs->md.external
* rs->md.chunk_sectors
* rs->md.new_chunk_sectors
* rs->md.dev_sectors
*/
return rs;
}
static void raid_set_free(struct raid_set *rs)
{
int i;
for (i = 0; i < rs->md.raid_disks; i++) {
if (rs->dev[i].meta_dev)
dm_put_device(rs->ti, rs->dev[i].meta_dev);
md_rdev_clear(&rs->dev[i].rdev);
if (rs->dev[i].data_dev)
dm_put_device(rs->ti, rs->dev[i].data_dev);
}
kfree(rs);
}
/*
* For every device we have two words
* <meta_dev>: meta device name or '-' if missing
* <data_dev>: data device name or '-' if missing
*
* The following are permitted:
* - -
* - <data_dev>
* <meta_dev> <data_dev>
*
* The following is not allowed:
* <meta_dev> -
*
* This code parses those words. If there is a failure,
* the caller must use raid_set_free() to unwind the operations.
*/
static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
{
int i;
int rebuild = 0;
int metadata_available = 0;
int r = 0;
const char *arg;
/* Put off the number of raid devices argument to get to dev pairs */
arg = dm_shift_arg(as);
if (!arg)
return -EINVAL;
for (i = 0; i < rs->md.raid_disks; i++) {
rs->dev[i].rdev.raid_disk = i;
rs->dev[i].meta_dev = NULL;
rs->dev[i].data_dev = NULL;
/*
* There are no offsets, since there is a separate device
* for data and metadata.
*/
rs->dev[i].rdev.data_offset = 0;
rs->dev[i].rdev.mddev = &rs->md;
arg = dm_shift_arg(as);
if (!arg)
return -EINVAL;
if (strcmp(arg, "-")) {
r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
&rs->dev[i].meta_dev);
if (r) {
rs->ti->error = "RAID metadata device lookup failure";
return r;
}
rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
if (!rs->dev[i].rdev.sb_page) {
rs->ti->error = "Failed to allocate superblock page";
return -ENOMEM;
}
}
arg = dm_shift_arg(as);
if (!arg)
return -EINVAL;
if (!strcmp(arg, "-")) {
if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
(!rs->dev[i].rdev.recovery_offset)) {
rs->ti->error = "Drive designated for rebuild not specified";
return -EINVAL;
}
if (rs->dev[i].meta_dev) {
rs->ti->error = "No data device supplied with metadata device";
return -EINVAL;
}
continue;
}
r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
&rs->dev[i].data_dev);
if (r) {
rs->ti->error = "RAID device lookup failure";
return r;
}
if (rs->dev[i].meta_dev) {
metadata_available = 1;
rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
}
rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
rebuild++;
}
if (metadata_available) {
rs->md.external = 0;
rs->md.persistent = 1;
rs->md.major_version = 2;
} else if (rebuild && !rs->md.recovery_cp) {
/*
* Without metadata, we will not be able to tell if the array
* is in-sync or not - we must assume it is not. Therefore,
* it is impossible to rebuild a drive.
*
* Even if there is metadata, the on-disk information may
* indicate that the array is not in-sync and it will then
* fail at that time.
*
* User could specify 'nosync' option if desperate.
*/
rs->ti->error = "Unable to rebuild drive while array is not in-sync";
return -EINVAL;
}
return 0;
}
/*
* validate_region_size
* @rs
* @region_size: region size in sectors. If 0, pick a size (4MiB default).
*
* Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
* Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
*
* Returns: 0 on success, -EINVAL on failure.
*/
static int validate_region_size(struct raid_set *rs, unsigned long region_size)
{
unsigned long min_region_size = rs->ti->len / (1 << 21);
if (!region_size) {
/*
* Choose a reasonable default. All figures in sectors.
*/
if (min_region_size > (1 << 13)) {
/* If not a power of 2, make it the next power of 2 */
region_size = roundup_pow_of_two(min_region_size);
DMINFO("Choosing default region size of %lu sectors",
region_size);
} else {
DMINFO("Choosing default region size of 4MiB");
region_size = 1 << 13; /* sectors */
}
} else {
/*
* Validate user-supplied value.
*/
if (region_size > rs->ti->len) {
rs->ti->error = "Supplied region size is too large";
return -EINVAL;
}
if (region_size < min_region_size) {
DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
region_size, min_region_size);
rs->ti->error = "Supplied region size is too small";
return -EINVAL;
}
if (!is_power_of_2(region_size)) {
rs->ti->error = "Region size is not a power of 2";
return -EINVAL;
}
if (region_size < rs->md.chunk_sectors) {
rs->ti->error = "Region size is smaller than the chunk size";
return -EINVAL;
}
}
/*
* Convert sectors to bytes.
*/
rs->md.bitmap_info.chunksize = (region_size << 9);
return 0;
}
/*
* validate_raid_redundancy
* @rs
*
* Determine if there are enough devices in the array that haven't
* failed (or are being rebuilt) to form a usable array.
*
* Returns: 0 on success, -EINVAL on failure.
*/
static int validate_raid_redundancy(struct raid_set *rs)
{
unsigned i, rebuild_cnt = 0;
unsigned rebuilds_per_group = 0, copies, d;
unsigned group_size, last_group_start;
for (i = 0; i < rs->md.raid_disks; i++)
if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
!rs->dev[i].rdev.sb_page)
rebuild_cnt++;
switch (rs->raid_type->level) {
case 1:
if (rebuild_cnt >= rs->md.raid_disks)
goto too_many;
break;
case 4:
case 5:
case 6:
if (rebuild_cnt > rs->raid_type->parity_devs)
goto too_many;
break;
case 10:
copies = raid10_md_layout_to_copies(rs->md.layout);
if (rebuild_cnt < copies)
break;
/*
* It is possible to have a higher rebuild count for RAID10,
* as long as the failed devices occur in different mirror
* groups (i.e. different stripes).
*
* When checking "near" format, make sure no adjacent devices
* have failed beyond what can be handled. In addition to the
* simple case where the number of devices is a multiple of the
* number of copies, we must also handle cases where the number
* of devices is not a multiple of the number of copies.
* E.g. dev1 dev2 dev3 dev4 dev5
* A A B B C
* C D D E E
*/
if (!strcmp("near", raid10_md_layout_to_format(rs->md.layout))) {
for (i = 0; i < rs->md.raid_disks * copies; i++) {
if (!(i % copies))
rebuilds_per_group = 0;
d = i % rs->md.raid_disks;
if ((!rs->dev[d].rdev.sb_page ||
!test_bit(In_sync, &rs->dev[d].rdev.flags)) &&
(++rebuilds_per_group >= copies))
goto too_many;
}
break;
}
/*
* When checking "far" and "offset" formats, we need to ensure
* that the device that holds its copy is not also dead or
* being rebuilt. (Note that "far" and "offset" formats only
* support two copies right now. These formats also only ever
* use the 'use_far_sets' variant.)
*
* This check is somewhat complicated by the need to account
* for arrays that are not a multiple of (far) copies. This
* results in the need to treat the last (potentially larger)
* set differently.
*/
group_size = (rs->md.raid_disks / copies);
last_group_start = (rs->md.raid_disks / group_size) - 1;
last_group_start *= group_size;
for (i = 0; i < rs->md.raid_disks; i++) {
if (!(i % copies) && !(i > last_group_start))
rebuilds_per_group = 0;
if ((!rs->dev[i].rdev.sb_page ||
!test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
(++rebuilds_per_group >= copies))
goto too_many;
}
break;
default:
if (rebuild_cnt)
return -EINVAL;
}
return 0;
too_many:
return -EINVAL;
}
/*
* Possible arguments are...
* <chunk_size> [optional_args]
*
* Argument definitions
* <chunk_size> The number of sectors per disk that
* will form the "stripe"
* [[no]sync] Force or prevent recovery of the
* entire array
* [rebuild <idx>] Rebuild the drive indicated by the index
* [daemon_sleep <ms>] Time between bitmap daemon work to
* clear bits
* [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
* [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
* [write_mostly <idx>] Indicate a write mostly drive via index
* [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
* [stripe_cache <sectors>] Stripe cache size for higher RAIDs
* [region_size <sectors>] Defines granularity of bitmap
*
* RAID10-only options:
* [raid10_copies <# copies>] Number of copies. (Default: 2)
* [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
*/
static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
unsigned num_raid_params)
{
int raid10_format = ALGORITHM_RAID10_DEFAULT;
unsigned raid10_copies = 2;
unsigned i;
unsigned value, region_size = 0;
sector_t sectors_per_dev = rs->ti->len;
sector_t max_io_len;
const char *arg, *key;
struct raid_dev *rd;
struct raid_type *rt = rs->raid_type;
arg = dm_shift_arg(as);
num_raid_params--; /* Account for chunk_size argument */
if (kstrtouint(arg, 10, &value) < 0) {
rs->ti->error = "Bad numerical argument given for chunk_size";
return -EINVAL;
}
/*
* First, parse the in-order required arguments
* "chunk_size" is the only argument of this type.
*/
if (rt_is_raid1(rt)) {
if (value)
DMERR("Ignoring chunk size parameter for RAID 1");
value = 0;
} else if (!is_power_of_2(value)) {
rs->ti->error = "Chunk size must be a power of 2";
return -EINVAL;
} else if (value < 8) {
rs->ti->error = "Chunk size value is too small";
return -EINVAL;
}
rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
/*
* We set each individual device as In_sync with a completed
* 'recovery_offset'. If there has been a device failure or
* replacement then one of the following cases applies:
*
* 1) User specifies 'rebuild'.
* - Device is reset when param is read.
* 2) A new device is supplied.
* - No matching superblock found, resets device.
* 3) Device failure was transient and returns on reload.
* - Failure noticed, resets device for bitmap replay.
* 4) Device hadn't completed recovery after previous failure.
* - Superblock is read and overrides recovery_offset.
*
* What is found in the superblocks of the devices is always
* authoritative, unless 'rebuild' or '[no]sync' was specified.
*/
for (i = 0; i < rs->md.raid_disks; i++) {
set_bit(In_sync, &rs->dev[i].rdev.flags);
rs->dev[i].rdev.recovery_offset = MaxSector;
}
/*
* Second, parse the unordered optional arguments
*/
for (i = 0; i < num_raid_params; i++) {
key = dm_shift_arg(as);
if (!key) {
rs->ti->error = "Not enough raid parameters given";
return -EINVAL;
}
if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
rs->ti->error = "Only one 'nosync' argument allowed";
return -EINVAL;
}
rs->md.recovery_cp = MaxSector;
continue;
}
if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
rs->ti->error = "Only one 'sync' argument allowed";
return -EINVAL;
}
rs->md.recovery_cp = 0;
continue;
}
if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
return -EINVAL;
}
continue;
}
arg = dm_shift_arg(as);
i++; /* Account for the argument pairs */
if (!arg) {
rs->ti->error = "Wrong number of raid parameters given";
return -EINVAL;
}
/*
* Parameters that take a string value are checked here.
*/
if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
rs->ti->error = "Only one 'raid10_format' argument pair allowed";
return -EINVAL;
}
if (!rt_is_raid10(rt)) {
rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
return -EINVAL;
}
raid10_format = raid10_name_to_format(arg);
if (raid10_format < 0) {
rs->ti->error = "Invalid 'raid10_format' value given";
return raid10_format;
}
continue;
}
if (kstrtouint(arg, 10, &value) < 0) {
rs->ti->error = "Bad numerical argument given in raid params";
return -EINVAL;
}
if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
/*
* "rebuild" is being passed in by userspace to provide
* indexes of replaced devices and to set up additional
* devices on raid level takeover.
*/
if (!__within_range(value, 0, rs->raid_disks - 1)) {
rs->ti->error = "Invalid rebuild index given";
return -EINVAL;
}
if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
rs->ti->error = "rebuild for this index already given";
return -EINVAL;
}
rd = rs->dev + value;
clear_bit(In_sync, &rd->rdev.flags);
clear_bit(Faulty, &rd->rdev.flags);
rd->rdev.recovery_offset = 0;
set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
if (!rt_is_raid1(rt)) {
rs->ti->error = "write_mostly option is only valid for RAID1";
return -EINVAL;
}
if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
rs->ti->error = "Invalid write_mostly index given";
return -EINVAL;
}
set_bit(WriteMostly, &rs->dev[value].rdev.flags);
set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
if (!rt_is_raid1(rt)) {
rs->ti->error = "max_write_behind option is only valid for RAID1";
return -EINVAL;
}
if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
rs->ti->error = "Only one max_write_behind argument pair allowed";
return -EINVAL;
}
/*
* In device-mapper, we specify things in sectors, but
* MD records this value in kB
*/
value /= 2;
if (value > COUNTER_MAX) {
rs->ti->error = "Max write-behind limit out of range";
return -EINVAL;
}
rs->md.bitmap_info.max_write_behind = value;
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
rs->ti->error = "Only one daemon_sleep argument pair allowed";
return -EINVAL;
}
if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
rs->ti->error = "daemon sleep period out of range";
return -EINVAL;
}
rs->md.bitmap_info.daemon_sleep = value;
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
/* Userspace passes new data_offset after having extended the the data image LV */
if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
rs->ti->error = "Only one data_offset argument pair allowed";
return -EINVAL;
}
/* Ensure sensible data offset */
if (value < 0) {
rs->ti->error = "Bogus data_offset value";
return -EINVAL;
}
rs->data_offset = value;
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
/* Define the +/-# of disks to add to/remove from the given raid set */
if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
rs->ti->error = "Only one delta_disks argument pair allowed";
return -EINVAL;
}
/* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
rs->ti->error = "Too many delta_disk requested";
return -EINVAL;
}
rs->delta_disks = value;
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
rs->ti->error = "Only one stripe_cache argument pair allowed";
return -EINVAL;
}
/*
* In device-mapper, we specify things in sectors, but
* MD records this value in kB
*/
value /= 2;
if (!rt_is_raid456(rt)) {
rs->ti->error = "Inappropriate argument: stripe_cache";
return -EINVAL;
}
if (raid5_set_cache_size(&rs->md, (int)value)) {
rs->ti->error = "Bad stripe_cache size";
return -EINVAL;
}
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
rs->ti->error = "Only one min_recovery_rate argument pair allowed";
return -EINVAL;
}
if (value > INT_MAX) {
rs->ti->error = "min_recovery_rate out of range";
return -EINVAL;
}
rs->md.sync_speed_min = (int)value;
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
rs->ti->error = "Only one max_recovery_rate argument pair allowed";
return -EINVAL;
}
if (value > INT_MAX) {
rs->ti->error = "max_recovery_rate out of range";
return -EINVAL;
}
rs->md.sync_speed_max = (int)value;
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
rs->ti->error = "Only one region_size argument pair allowed";
return -EINVAL;
}
region_size = value;
} else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
rs->ti->error = "Only one raid10_copies argument pair allowed";
return -EINVAL;
}
if (!__within_range(value, 2, rs->md.raid_disks)) {
rs->ti->error = "Bad value for 'raid10_copies'";
return -EINVAL;
}
raid10_copies = value;
} else {
DMERR("Unable to parse RAID parameter: %s", key);
rs->ti->error = "Unable to parse RAID parameter";
return -EINVAL;
}
}
if (validate_region_size(rs, region_size))
return -EINVAL;
if (rs->md.chunk_sectors)
max_io_len = rs->md.chunk_sectors;
else
max_io_len = region_size;
if (dm_set_target_max_io_len(rs->ti, max_io_len))
return -EINVAL;
if (rt_is_raid10(rt)) {
if (raid10_copies > rs->md.raid_disks) {
rs->ti->error = "Not enough devices to satisfy specification";
return -EINVAL;
}
rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
if (rs->md.new_layout < 0) {
rs->ti->error = "Error getting raid10 format";
return rs->md.new_layout;
}
rt = get_raid_type_by_ll(10, rs->md.new_layout);
if (!rt) {
rs->ti->error = "Failed to recognize new raid10 layout";
return -EINVAL;
}
if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
rt->algorithm == ALGORITHM_RAID10_NEAR) &&
test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
return -EINVAL;
}
/* (Len * #mirrors) / #devices */
sectors_per_dev = rs->ti->len * raid10_copies;
sector_div(sectors_per_dev, rs->md.raid_disks);
rs->md.layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
rs->md.new_layout = rs->md.layout;
} else if (!rt_is_raid1(rt) &&
sector_div(sectors_per_dev, (rs->md.raid_disks - rt->parity_devs))) {
rs->ti->error = "Target length not divisible by number of data devices";
return -EINVAL;
}
rs->raid10_copies = raid10_copies;
rs->md.dev_sectors = sectors_per_dev;
/* Assume there are no metadata devices until the drives are parsed */
rs->md.persistent = 0;
rs->md.external = 1;
/* Check, if any invalid ctr arguments have been passed in for the raid level */
return rs_check_for_valid_flags(rs);
}
/* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
static unsigned int mddev_data_stripes(struct raid_set *rs)
{
return rs->md.raid_disks - rs->raid_type->parity_devs;
}
static void do_table_event(struct work_struct *ws)
{
struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
dm_table_event(rs->ti->table);
}
static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
{
struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
return mddev_congested(&rs->md, bits);
}
/*
* Make sure a valid takover (level switch) is being requested on @rs
*
* Conversions of raid sets from one MD personality to another
* have to conform to restrictions which are enforced here.
*
* Degration is already checked for in rs_check_conversion() below.
*/
static int rs_check_takeover(struct raid_set *rs)
{
struct mddev *mddev = &rs->md;
unsigned int near_copies;
switch (mddev->level) {
case 0:
/* raid0 -> raid1/5 with one disk */
if ((mddev->new_level == 1 || mddev->new_level == 5) &&
mddev->raid_disks == 1)
return 0;
/* raid0 -> raid10 */
if (mddev->new_level == 10 &&
!(rs->raid_disks % 2))
return 0;
/* raid0 with multiple disks -> raid4/5/6 */
if (__within_range(mddev->new_level, 4, 6) &&
mddev->new_layout == ALGORITHM_PARITY_N &&
mddev->raid_disks > 1)
return 0;
break;
case 10:
/* Can't takeover raid10_offset! */
if (__is_raid10_offset(mddev->layout))
break;
near_copies = __raid10_near_copies(mddev->layout);
/* raid10* -> raid0 */
if (mddev->new_level == 0) {
/* Can takeover raid10_near with raid disks divisable by data copies! */
if (near_copies > 1 &&
!(mddev->raid_disks % near_copies)) {
mddev->raid_disks /= near_copies;
mddev->delta_disks = mddev->raid_disks;
return 0;
}
/* Can takeover raid10_far */
if (near_copies == 1 &&
__raid10_far_copies(mddev->layout) > 1)
return 0;
break;
}
/* raid10_{near,far} -> raid1 */
if (mddev->new_level == 1 &&
max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
return 0;
/* raid10_{near,far} with 2 disks -> raid4/5 */
if (__within_range(mddev->new_level, 4, 5) &&
mddev->raid_disks == 2)
return 0;
break;
case 1:
/* raid1 with 2 disks -> raid4/5 */
if (__within_range(mddev->new_level, 4, 5) &&
mddev->raid_disks == 2) {
mddev->degraded = 1;
return 0;
}
/* raid1 -> raid0 */
if (mddev->new_level == 0 &&
mddev->raid_disks == 1)
return 0;
/* raid1 -> raid10 */
if (mddev->new_level == 10)
return 0;
break;
case 4:
/* raid4 -> raid0 */
if (mddev->new_level == 0)
return 0;
/* raid4 -> raid1/5 with 2 disks */
if ((mddev->new_level == 1 || mddev->new_level == 5) &&
mddev->raid_disks == 2)
return 0;
/* raid4 -> raid5/6 with parity N */
if (__within_range(mddev->new_level, 5, 6) &&
mddev->layout == ALGORITHM_PARITY_N)
return 0;
break;
case 5:
/* raid5 with parity N -> raid0 */
if (mddev->new_level == 0 &&
mddev->layout == ALGORITHM_PARITY_N)
return 0;
/* raid5 with parity N -> raid4 */
if (mddev->new_level == 4 &&
mddev->layout == ALGORITHM_PARITY_N)
return 0;
/* raid5 with 2 disks -> raid1/4/10 */
if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
mddev->raid_disks == 2)
return 0;
/* raid5 with parity N -> raid6 with parity N */
if (mddev->new_level == 6 &&
((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
__within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
return 0;
break;
case 6:
/* raid6 with parity N -> raid0 */
if (mddev->new_level == 0 &&
mddev->layout == ALGORITHM_PARITY_N)
return 0;
/* raid6 with parity N -> raid4 */
if (mddev->new_level == 4 &&
mddev->layout == ALGORITHM_PARITY_N)
return 0;
/* raid6_*_n with parity N -> raid5_* */
if (mddev->new_level == 5 &&
((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
__within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
return 0;
default:
break;
}
rs->ti->error = "takeover not possible";
return -EINVAL;
}
/* True if @rs requested to be taken over */
static bool rs_takeover_requested(struct raid_set *rs)
{
return rs->md.new_level != rs->md.level;
}
/* Features */
#define FEATURE_FLAG_SUPPORTS_V190 0x1 /* Supports extended superblock */
/* State flags for sb->flags */
#define SB_FLAG_RESHAPE_ACTIVE 0x1
#define SB_FLAG_RESHAPE_BACKWARDS 0x2
/*
* This structure is never routinely used by userspace, unlike md superblocks.
* Devices with this superblock should only ever be accessed via device-mapper.
*/
#define DM_RAID_MAGIC 0x64526D44
struct dm_raid_superblock {
__le32 magic; /* "DmRd" */
__le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
__le32 num_devices; /* Number of devices in this raid set. (Max 64) */
__le32 array_position; /* The position of this drive in the raid set */
__le64 events; /* Incremented by md when superblock updated */
__le64 failed_devices; /* Pre 1.9.0 part of bit field of devices to */
/* indicate failures (see extension below) */
/*
* This offset tracks the progress of the repair or replacement of
* an individual drive.
*/
__le64 disk_recovery_offset;
/*
* This offset tracks the progress of the initial raid set
* synchronisation/parity calculation.
*/
__le64 array_resync_offset;
/*
* raid characteristics
*/
__le32 level;
__le32 layout;
__le32 stripe_sectors;
/********************************************************************
* BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
*
* FEATURE_FLAG_SUPPORTS_V190 in the features member indicates that those exist
*/
__le32 flags; /* Flags defining array states for reshaping */
/*
* This offset tracks the progress of a raid
* set reshape in order to be able to restart it
*/
__le64 reshape_position;
/*
* These define the properties of the array in case of an interrupted reshape
*/
__le32 new_level;
__le32 new_layout;
__le32 new_stripe_sectors;
__le32 delta_disks;
__le64 array_sectors; /* Array size in sectors */
/*
* Sector offsets to data on devices (reshaping).
* Needed to support out of place reshaping, thus
* not writing over any stripes whilst converting
* them from old to new layout
*/
__le64 data_offset;
__le64 new_data_offset;
__le64 sectors; /* Used device size in sectors */
/*
* Additonal Bit field of devices indicating failures to support
* up to 256 devices with the 1.9.0 on-disk metadata format
*/
__le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
__le32 incompat_features; /* Used to indicate any incompatible features */
/* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
} __packed;
static int read_disk_sb(struct md_rdev *rdev, int size)
{
BUG_ON(!rdev->sb_page);
if (rdev->sb_loaded)
return 0;
if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, 1)) {
DMERR("Failed to read superblock of device at position %d",
rdev->raid_disk);
md_error(rdev->mddev, rdev);
return -EINVAL;
}
rdev->sb_loaded = 1;
return 0;
}
static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
{
failed_devices[0] = le64_to_cpu(sb->failed_devices);
memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
int i = ARRAY_SIZE(sb->extended_failed_devices);
while (i--)
failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
}
}
static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
{
int i = ARRAY_SIZE(sb->extended_failed_devices);
sb->failed_devices = cpu_to_le64(failed_devices[0]);
while (i--)
sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
}
/*
* Synchronize the superblock members with the raid set properties
*
* All superblock data is little endian.
*/
static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
{
bool update_failed_devices = false;
unsigned int i;
uint64_t failed_devices[DISKS_ARRAY_ELEMS];
struct dm_raid_superblock *sb;
struct raid_set *rs = container_of(mddev, struct raid_set, md);
/* No metadata device, no superblock */
if (!rdev->meta_bdev)
return;
BUG_ON(!rdev->sb_page);
sb = page_address(rdev->sb_page);
sb_retrieve_failed_devices(sb, failed_devices);
for (i = 0; i < rs->raid_disks; i++)
if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
update_failed_devices = true;
set_bit(i, (void *) failed_devices);
}
if (update_failed_devices)
sb_update_failed_devices(sb, failed_devices);
sb->magic = cpu_to_le32(DM_RAID_MAGIC);
sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
sb->num_devices = cpu_to_le32(mddev->raid_disks);
sb->array_position = cpu_to_le32(rdev->raid_disk);
sb->events = cpu_to_le64(mddev->events);
sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
sb->level = cpu_to_le32(mddev->level);
sb->layout = cpu_to_le32(mddev->layout);
sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
sb->new_level = cpu_to_le32(mddev->new_level);
sb->new_layout = cpu_to_le32(mddev->new_layout);
sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
sb->delta_disks = cpu_to_le32(mddev->delta_disks);
smp_rmb(); /* Make sure we access most recent reshape position */
sb->reshape_position = cpu_to_le64(mddev->reshape_position);
if (le64_to_cpu(sb->reshape_position) != MaxSector) {
/* Flag ongoing reshape */
sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
if (mddev->delta_disks < 0 || mddev->reshape_backwards)
sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
} else {
/* Clear reshape flags */
sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
}
sb->array_sectors = cpu_to_le64(mddev->array_sectors);
sb->data_offset = cpu_to_le64(rdev->data_offset);
sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
sb->sectors = cpu_to_le64(rdev->sectors);
/* Zero out the rest of the payload after the size of the superblock */
memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
}
/*
* super_load
*
* This function creates a superblock if one is not found on the device
* and will decide which superblock to use if there's a choice.
*
* Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
*/
static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
{
int r;
struct dm_raid_superblock *sb;
struct dm_raid_superblock *refsb;
uint64_t events_sb, events_refsb;
rdev->sb_start = 0;
rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) {
DMERR("superblock size of a logical block is no longer valid");
return -EINVAL;
}
r = read_disk_sb(rdev, rdev->sb_size);
if (r)
return r;
sb = page_address(rdev->sb_page);
/*
* Two cases that we want to write new superblocks and rebuild:
* 1) New device (no matching magic number)
* 2) Device specified for rebuild (!In_sync w/ offset == 0)
*/
if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
(!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
super_sync(rdev->mddev, rdev);
set_bit(FirstUse, &rdev->flags);
sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
/* Force writing of superblocks to disk */
set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags);
/* Any superblock is better than none, choose that if given */
return refdev ? 0 : 1;
}
if (!refdev)
return 1;
events_sb = le64_to_cpu(sb->events);
refsb = page_address(refdev->sb_page);
events_refsb = le64_to_cpu(refsb->events);
return (events_sb > events_refsb) ? 1 : 0;
}
static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
{
int role;
unsigned int d;
struct mddev *mddev = &rs->md;
uint64_t events_sb;
uint64_t failed_devices[DISKS_ARRAY_ELEMS];
struct dm_raid_superblock *sb;
uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
struct md_rdev *r;
struct dm_raid_superblock *sb2;
sb = page_address(rdev->sb_page);
events_sb = le64_to_cpu(sb->events);
/*
* Initialise to 1 if this is a new superblock.
*/
mddev->events = events_sb ? : 1;
mddev->reshape_position = MaxSector;
/*
* Reshaping is supported, e.g. reshape_position is valid
* in superblock and superblock content is authoritative.
*/
if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
/* Superblock is authoritative wrt given raid set layout! */
mddev->raid_disks = le32_to_cpu(sb->num_devices);
mddev->level = le32_to_cpu(sb->level);
mddev->layout = le32_to_cpu(sb->layout);
mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
mddev->new_level = le32_to_cpu(sb->new_level);
mddev->new_layout = le32_to_cpu(sb->new_layout);
mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
mddev->delta_disks = le32_to_cpu(sb->delta_disks);
mddev->array_sectors = le64_to_cpu(sb->array_sectors);
/* raid was reshaping and got interrupted */
if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
DMERR("Reshape requested but raid set is still reshaping");
return -EINVAL;
}
if (mddev->delta_disks < 0 ||
(!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
mddev->reshape_backwards = 1;
else
mddev->reshape_backwards = 0;
mddev->reshape_position = le64_to_cpu(sb->reshape_position);
rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
}
} else {
/*
* No takeover/reshaping, because we don't have the extended v1.9.0 metadata
*/
if (le32_to_cpu(sb->level) != mddev->level) {
DMERR("Reshaping/takeover raid sets not yet supported. (raid level/stripes/size change)");
return -EINVAL;
}
if (le32_to_cpu(sb->layout) != mddev->layout) {
DMERR("Reshaping raid sets not yet supported. (raid layout change)");
DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout);
DMERR(" Old layout: %s w/ %d copies",
raid10_md_layout_to_format(le32_to_cpu(sb->layout)),
raid10_md_layout_to_copies(le32_to_cpu(sb->layout)));
DMERR(" New layout: %s w/ %d copies",
raid10_md_layout_to_format(mddev->layout),
raid10_md_layout_to_copies(mddev->layout));
return -EINVAL;
}
if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) {
DMERR("Reshaping raid sets not yet supported. (stripe sectors change)");
return -EINVAL;
}
/* We can only change the number of devices in raid1 with old (i.e. pre 1.0.7) metadata */
if (!rt_is_raid1(rs->raid_type) &&
(le32_to_cpu(sb->num_devices) != mddev->raid_disks)) {
DMERR("Reshaping raid sets not yet supported. (device count change from %u to %u)",
sb->num_devices, mddev->raid_disks);
return -EINVAL;
}
/* Table line is checked vs. authoritative superblock */
rs_set_new(rs);
}
if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
/*
* During load, we set FirstUse if a new superblock was written.
* There are two reasons we might not have a superblock:
* 1) The raid set is brand new - in which case, all of the
* devices must have their In_sync bit set. Also,
* recovery_cp must be 0, unless forced.
* 2) This is a new device being added to an old raid set
* and the new device needs to be rebuilt - in which
* case the In_sync bit will /not/ be set and
* recovery_cp must be MaxSector.
*/
d = 0;
rdev_for_each(r, mddev) {
if (test_bit(FirstUse, &r->flags))
new_devs++;
if (!test_bit(In_sync, &r->flags)) {
DMINFO("Device %d specified for rebuild; clearing superblock",
r->raid_disk);
rebuilds++;
if (test_bit(FirstUse, &r->flags))
rebuild_and_new++;
}
d++;
}
if (new_devs == rs->raid_disks || !rebuilds) {
/* Replace a broken device */
if (new_devs == 1 && !rs->delta_disks)
;
if (new_devs == rs->raid_disks) {
DMINFO("Superblocks created for new raid set");
set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
mddev->recovery_cp = 0;
} else if (new_devs && new_devs != rs->raid_disks && !rebuilds) {
DMERR("New device injected into existing raid set without "
"'delta_disks' or 'rebuild' parameter specified");
return -EINVAL;
}
} else if (new_devs && new_devs != rebuilds) {
DMERR("%u 'rebuild' devices cannot be injected into"
" a raid set with %u other first-time devices",
rebuilds, new_devs);
return -EINVAL;
} else if (rebuilds) {
if (rebuild_and_new && rebuilds != rebuild_and_new) {
DMERR("new device%s provided without 'rebuild'",
new_devs > 1 ? "s" : "");
return -EINVAL;
} else if (mddev->recovery_cp != MaxSector) {
DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
(unsigned long long) mddev->recovery_cp);
return -EINVAL;
} else if (mddev->reshape_position != MaxSector) {
DMERR("'rebuild' specified while raid set is being reshaped");
return -EINVAL;
}
}
/*
* Now we set the Faulty bit for those devices that are
* recorded in the superblock as failed.
*/
sb_retrieve_failed_devices(sb, failed_devices);
rdev_for_each(r, mddev) {
if (!r->sb_page)
continue;
sb2 = page_address(r->sb_page);
sb2->failed_devices = 0;
memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
/*
* Check for any device re-ordering.
*/
if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
role = le32_to_cpu(sb2->array_position);
if (role < 0)
continue;
if (role != r->raid_disk) {
if (__is_raid10_near(mddev->layout)) {
if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
rs->raid_disks % rs->raid10_copies) {
rs->ti->error =
"Cannot change raid10 near set to odd # of devices!";
return -EINVAL;
}
sb2->array_position = cpu_to_le32(r->raid_disk);
} else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
!(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
!rt_is_raid1(rs->raid_type)) {
rs->ti->error = "Cannot change device positions in raid set";
return -EINVAL;
}
DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
}
/*
* Partial recovery is performed on
* returning failed devices.
*/
if (test_bit(role, (void *) failed_devices))
set_bit(Faulty, &r->flags);
}
}
return 0;
}
static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
{
struct mddev *mddev = &rs->md;
struct dm_raid_superblock *sb;
if (rs_is_raid0(rs) || !rdev->sb_page)
return 0;
sb = page_address(rdev->sb_page);
/*
* If mddev->events is not set, we know we have not yet initialized
* the array.
*/
if (!mddev->events && super_init_validation(rs, rdev))
return -EINVAL;
if (le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
return -EINVAL;
}
if (sb->incompat_features) {
rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
return -EINVAL;
}
/* Enable bitmap creation for RAID levels != 0 */
mddev->bitmap_info.offset = rt_is_raid0(rs->raid_type) ? 0 : to_sector(4096);
rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
/* Retrieve device size stored in superblock to be prepared for shrink */
rdev->sectors = le64_to_cpu(sb->sectors);
rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
if (rdev->recovery_offset == MaxSector)
set_bit(In_sync, &rdev->flags);
/*
* If no reshape in progress -> we're recovering single
* disk(s) and have to set the device(s) to out-of-sync
*/
else if (rs->md.reshape_position == MaxSector)
clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
}
/*
* If a device comes back, set it as not In_sync and no longer faulty.
*/
if (test_and_clear_bit(Faulty, &rdev->flags)) {
rdev->recovery_offset = 0;
clear_bit(In_sync, &rdev->flags);
rdev->saved_raid_disk = rdev->raid_disk;
}
/* Reshape support -> restore repective data offsets */
rdev->data_offset = le64_to_cpu(sb->data_offset);
rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
return 0;
}
/*
* Analyse superblocks and select the freshest.
*/
static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
{
int r;
struct raid_dev *dev;
struct md_rdev *rdev, *tmp, *freshest;
struct mddev *mddev = &rs->md;
freshest = NULL;
rdev_for_each_safe(rdev, tmp, mddev) {
/*
* Skipping super_load due to CTR_FLAG_SYNC will cause
* the array to undergo initialization again as
* though it were new. This is the intended effect
* of the "sync" directive.
*
* When reshaping capability is added, we must ensure
* that the "sync" directive is disallowed during the
* reshape.
*/
if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
continue;
if (!rdev->meta_bdev)
continue;
r = super_load(rdev, freshest);
switch (r) {
case 1:
freshest = rdev;
break;
case 0:
break;
default:
dev = container_of(rdev, struct raid_dev, rdev);
if (dev->meta_dev)
dm_put_device(ti, dev->meta_dev);
dev->meta_dev = NULL;
rdev->meta_bdev = NULL;
if (rdev->sb_page)
put_page(rdev->sb_page);
rdev->sb_page = NULL;
rdev->sb_loaded = 0;
/*
* We might be able to salvage the data device
* even though the meta device has failed. For
* now, we behave as though '- -' had been
* set for this device in the table.
*/
if (dev->data_dev)
dm_put_device(ti, dev->data_dev);
dev->data_dev = NULL;
rdev->bdev = NULL;
list_del(&rdev->same_set);
}
}
if (!freshest)
return 0;
if (validate_raid_redundancy(rs)) {
rs->ti->error = "Insufficient redundancy to activate array";
return -EINVAL;
}
/*
* Validation of the freshest device provides the source of
* validation for the remaining devices.
*/
if (super_validate(rs, freshest)) {
rs->ti->error = "Unable to assemble array: Invalid superblocks";
return -EINVAL;
}
rdev_for_each(rdev, mddev)
if ((rdev != freshest) && super_validate(rs, rdev))
return -EINVAL;
return 0;
}
/* Userpace reordered disks -> adjust raid_disk indexes in @rs */
static void __reorder_raid_disk_indexes(struct raid_set *rs)
{
int i = 0;
struct md_rdev *rdev;
rdev_for_each(rdev, &rs->md) {
rdev->raid_disk = i++;
rdev->saved_raid_disk = rdev->new_raid_disk = -1;
}
}
/*
* Setup @rs for takeover by a different raid level
*/
static int rs_setup_takeover(struct raid_set *rs)
{
struct mddev *mddev = &rs->md;
struct md_rdev *rdev;
unsigned int d = mddev->raid_disks = rs->raid_disks;
sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
if (rt_is_raid10(rs->raid_type)) {
if (mddev->level == 0) {
/* Userpace reordered disks -> adjust raid_disk indexes */
__reorder_raid_disk_indexes(rs);
/* raid0 -> raid10_far layout */
mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
rs->raid10_copies);
} else if (mddev->level == 1)
/* raid1 -> raid10_near layout */
mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
rs->raid_disks);
else
return -EINVAL;
}
clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
mddev->recovery_cp = MaxSector;
while (d--) {
rdev = &rs->dev[d].rdev;
if (test_bit(d, (void *) rs->rebuild_disks)) {
clear_bit(In_sync, &rdev->flags);
clear_bit(Faulty, &rdev->flags);
mddev->recovery_cp = rdev->recovery_offset = 0;
/* Bitmap has to be created when we do an "up" takeover */
set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
}
rdev->new_data_offset = new_data_offset;
}
return 0;
}
/*
* Enable/disable discard support on RAID set depending on
* RAID level and discard properties of underlying RAID members.
*/
static void configure_discard_support(struct raid_set *rs)
{
int i;
bool raid456;
struct dm_target *ti = rs->ti;
/* Assume discards not supported until after checks below. */
ti->discards_supported = false;
/* RAID level 4,5,6 require discard_zeroes_data for data integrity! */
raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6);
for (i = 0; i < rs->md.raid_disks; i++) {
struct request_queue *q;
if (!rs->dev[i].rdev.bdev)
continue;
q = bdev_get_queue(rs->dev[i].rdev.bdev);
if (!q || !blk_queue_discard(q))
return;
if (raid456) {
if (!q->limits.discard_zeroes_data)
return;
if (!devices_handle_discard_safely) {
DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
return;
}
}
}
/* All RAID members properly support discards */
ti->discards_supported = true;
/*
* RAID1 and RAID10 personalities require bio splitting,
* RAID0/4/5/6 don't and process large discard bios properly.
*/
ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10);
ti->num_discard_bios = 1;
}
/*
* Construct a RAID0/1/10/4/5/6 mapping:
* Args:
* <raid_type> <#raid_params> <raid_params>{0,} \
* <#raid_devs> [<meta_dev1> <dev1>]{1,}
*
* <raid_params> varies by <raid_type>. See 'parse_raid_params' for
* details on possible <raid_params>.
*
* Userspace is free to initialize the metadata devices, hence the superblocks to
* enforce recreation based on the passed in table parameters.
*
*/
static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv)
{
int r;
struct raid_type *rt;
unsigned num_raid_params, num_raid_devs;
struct raid_set *rs = NULL;
const char *arg;
struct dm_arg_set as = { argc, argv }, as_nrd;
struct dm_arg _args[] = {
{ 0, as.argc, "Cannot understand number of raid parameters" },
{ 1, 254, "Cannot understand number of raid devices parameters" }
};
/* Must have <raid_type> */
arg = dm_shift_arg(&as);
if (!arg) {
ti->error = "No arguments";
return -EINVAL;
}
rt = get_raid_type(arg);
if (!rt) {
ti->error = "Unrecognised raid_type";
return -EINVAL;
}
/* Must have <#raid_params> */
if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
return -EINVAL;
/* number of raid device tupples <meta_dev data_dev> */
as_nrd = as;
dm_consume_args(&as_nrd, num_raid_params);
_args[1].max = (as_nrd.argc - 1) / 2;
if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
return -EINVAL;
if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
ti->error = "Invalid number of supplied raid devices";
return -EINVAL;
}
rs = raid_set_alloc(ti, rt, num_raid_devs);
if (IS_ERR(rs))
return PTR_ERR(rs);
r = parse_raid_params(rs, &as, num_raid_params);
if (r)
goto bad;
r = parse_dev_params(rs, &as);
if (r)
goto bad;
rs->md.sync_super = super_sync;
/*
* Backup any new raid set level, layout, ...
* requested to be able to compare to superblock
* members for conversion decisions.
*/
rs_config_backup(rs);
r = analyse_superblocks(ti, rs);
if (r)
goto bad;
INIT_WORK(&rs->md.event_work, do_table_event);
ti->private = rs;
ti->num_flush_bios = 1;
/* Restore any requested new layout for conversion decision */
rs_config_restore(rs);
/*
* If a takeover is needed, just set the level to
* the new requested one and allow the raid set to run.
*/
if (rs_takeover_requested(rs)) {
r = rs_check_takeover(rs);
if (r)
return r;
r = rs_setup_takeover(rs);
if (r)
return r;
/* Tell preresume to update superblocks with new layout */
set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
rs_set_new(rs);
} else
rs_set_cur(rs);
/* Start raid set read-only and assumed clean to change in raid_resume() */
rs->md.ro = 1;
rs->md.in_sync = 1;
set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
/* Has to be held on running the array */
mddev_lock_nointr(&rs->md);
r = md_run(&rs->md);
rs->md.in_sync = 0; /* Assume already marked dirty */
mddev_unlock(&rs->md);
if (r) {
ti->error = "Fail to run raid array";
goto bad;
}
if (ti->len != rs->md.array_sectors) {
ti->error = "Array size does not match requested target length";
r = -EINVAL;
goto size_mismatch;
}
rs->callbacks.congested_fn = raid_is_congested;
dm_table_add_target_callbacks(ti->table, &rs->callbacks);
mddev_suspend(&rs->md);
return 0;
size_mismatch:
md_stop(&rs->md);
bad:
raid_set_free(rs);
return r;
}
static void raid_dtr(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
list_del_init(&rs->callbacks.list);
md_stop(&rs->md);
raid_set_free(rs);
}
static int raid_map(struct dm_target *ti, struct bio *bio)
{
struct raid_set *rs = ti->private;
struct mddev *mddev = &rs->md;
mddev->pers->make_request(mddev, bio);
return DM_MAPIO_SUBMITTED;
}
/* Return string describing the current sync action of @mddev */
static const char *decipher_sync_action(struct mddev *mddev)
{
if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
return "frozen";
if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
(!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
return "reshape";
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
return "resync";
else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
return "check";
return "repair";
}
if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
return "recover";
}
return "idle";
}
/*
* Return status string @rdev
*
* Status characters:
*
* 'D' = Dead/Failed device
* 'a' = Alive but not in-sync
* 'A' = Alive and in-sync
*/
static const char *__raid_dev_status(struct md_rdev *rdev, bool array_in_sync)
{
if (test_bit(Faulty, &rdev->flags))
return "D";
else if (!array_in_sync || !test_bit(In_sync, &rdev->flags))
return "a";
else
return "A";
}
/* Helper to return resync/reshape progress for @rs and @array_in_sync */
static sector_t rs_get_progress(struct raid_set *rs,
sector_t resync_max_sectors, bool *array_in_sync)
{
sector_t r, recovery_cp, curr_resync_completed;
struct mddev *mddev = &rs->md;
curr_resync_completed = mddev->curr_resync_completed ?: mddev->recovery_cp;
recovery_cp = mddev->recovery_cp;
*array_in_sync = false;
if (rs_is_raid0(rs)) {
r = resync_max_sectors;
*array_in_sync = true;
} else {
r = mddev->reshape_position;
/* Reshape is relative to the array size */
if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ||
r != MaxSector) {
if (r == MaxSector) {
*array_in_sync = true;
r = resync_max_sectors;
} else {
/* Got to reverse on backward reshape */
if (mddev->reshape_backwards)
r = mddev->array_sectors - r;
/* Devide by # of data stripes */
sector_div(r, mddev_data_stripes(rs));
}
/* Sync is relative to the component device size */
} else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
r = curr_resync_completed;
else
r = recovery_cp;
if (r == MaxSector) {
/*
* Sync complete.
*/
*array_in_sync = true;
r = resync_max_sectors;
} else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
/*
* If "check" or "repair" is occurring, the raid set has
* undergone an initial sync and the health characters
* should not be 'a' anymore.
*/
*array_in_sync = true;
} else {
struct md_rdev *rdev;
/*
* The raid set may be doing an initial sync, or it may
* be rebuilding individual components. If all the
* devices are In_sync, then it is the raid set that is
* being initialized.
*/
rdev_for_each(rdev, mddev)
if (!test_bit(In_sync, &rdev->flags))
*array_in_sync = true;
#if 0
r = 0; /* HM FIXME: TESTME: https://bugzilla.redhat.com/show_bug.cgi?id=1210637 ? */
#endif
}
}
return r;
}
/* Helper to return @dev name or "-" if !@dev */
static const char *__get_dev_name(struct dm_dev *dev)
{
return dev ? dev->name : "-";
}
static void raid_status(struct dm_target *ti, status_type_t type,
unsigned int status_flags, char *result, unsigned int maxlen)
{
struct raid_set *rs = ti->private;
struct mddev *mddev = &rs->md;
struct r5conf *conf = mddev->private;
int max_nr_stripes = conf ? conf->max_nr_stripes : 0;
bool array_in_sync;
unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
unsigned int sz = 0;
unsigned int write_mostly_params = 0;
sector_t progress, resync_max_sectors, resync_mismatches;
const char *sync_action;
struct raid_type *rt;
struct md_rdev *rdev;
switch (type) {
case STATUSTYPE_INFO:
/* *Should* always succeed */
rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
if (!rt)
return;
DMEMIT("%s %d ", rt ? rt->name : "unknown", mddev->raid_disks);
/* Access most recent mddev properties for status output */
smp_rmb();
/* Get sensible max sectors even if raid set not yet started */
resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
mddev->resync_max_sectors : mddev->dev_sectors;
progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync);
resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
(unsigned int) atomic64_read(&mddev->resync_mismatches) : 0;
sync_action = decipher_sync_action(&rs->md);
/* HM FIXME: do we want another state char for raid0? It shows 'D' or 'A' now */
rdev_for_each(rdev, mddev)
DMEMIT(__raid_dev_status(rdev, array_in_sync));
/*
* In-sync/Reshape ratio:
* The in-sync ratio shows the progress of:
* - Initializing the raid set
* - Rebuilding a subset of devices of the raid set
* The user can distinguish between the two by referring
* to the status characters.
*
* The reshape ratio shows the progress of
* changing the raid layout or the number of
* disks of a raid set
*/
DMEMIT(" %llu/%llu", (unsigned long long) progress,
(unsigned long long) resync_max_sectors);
/*
* v1.5.0+:
*
* Sync action:
* See Documentation/device-mapper/dm-raid.txt for
* information on each of these states.
*/
DMEMIT(" %s", sync_action);
/*
* v1.5.0+:
*
* resync_mismatches/mismatch_cnt
* This field shows the number of discrepancies found when
* performing a "check" of the raid set.
*/
DMEMIT(" %llu", (unsigned long long) resync_mismatches);
/*
* v1.9.0+:
*
* data_offset (needed for out of space reshaping)
* This field shows the data offset into the data
* image LV where the first stripes data starts.
*
* We keep data_offset equal on all raid disks of the set,
* so retrieving it from the first raid disk is sufficient.
*/
DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
break;
case STATUSTYPE_TABLE:
/* Report the table line string you would use to construct this raid set */
/* Calculate raid parameter count */
rdev_for_each(rdev, mddev)
if (test_bit(WriteMostly, &rdev->flags))
write_mostly_params += 2;
raid_param_cnt += memweight(rs->rebuild_disks,
DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks)) * 2 +
write_mostly_params +
hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
/* Emit table line */
DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
raid10_md_layout_to_format(mddev->layout));
if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
raid10_md_layout_to_copies(mddev->layout));
if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
(unsigned long long) to_sector(mddev->bitmap_info.chunksize));
if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
(unsigned long long) rs->data_offset);
if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
mddev->bitmap_info.daemon_sleep);
if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
mddev->delta_disks);
if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
max_nr_stripes);
rdev_for_each(rdev, mddev)
if (test_bit(rdev->raid_disk, (void *) rs->rebuild_disks))
DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD),
rdev->raid_disk);
rdev_for_each(rdev, mddev)
if (test_bit(WriteMostly, &rdev->flags))
DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
rdev->raid_disk);
if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
mddev->bitmap_info.max_write_behind);
if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
mddev->sync_speed_max);
if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
mddev->sync_speed_min);
DMEMIT(" %d", rs->raid_disks);
rdev_for_each(rdev, mddev) {
struct raid_dev *rd = container_of(rdev, struct raid_dev, rdev);
DMEMIT(" %s %s", __get_dev_name(rd->meta_dev),
__get_dev_name(rd->data_dev));
}
}
}
static int raid_message(struct dm_target *ti, unsigned argc, char **argv)
{
struct raid_set *rs = ti->private;
struct mddev *mddev = &rs->md;
if (!strcasecmp(argv[0], "reshape")) {
DMERR("Reshape not supported.");
return -EINVAL;
}
if (!mddev->pers || !mddev->pers->sync_request)
return -EINVAL;
if (!strcasecmp(argv[0], "frozen"))
set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
else
clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
if (mddev->sync_thread) {
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
md_reap_sync_thread(mddev);
}
} else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
return -EBUSY;
else if (!strcasecmp(argv[0], "resync"))
; /* MD_RECOVERY_NEEDED set below */
else if (!strcasecmp(argv[0], "recover"))
set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
else {
if (!strcasecmp(argv[0], "check"))
set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
else if (!!strcasecmp(argv[0], "repair"))
return -EINVAL;
set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
}
if (mddev->ro == 2) {
/* A write to sync_action is enough to justify
* canceling read-auto mode
*/
mddev->ro = 0;
if (!mddev->suspended && mddev->sync_thread)
md_wakeup_thread(mddev->sync_thread);
}
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
if (!mddev->suspended && mddev->thread)
md_wakeup_thread(mddev->thread);
return 0;
}
static int raid_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
struct raid_set *rs = ti->private;
unsigned i;
int r = 0;
for (i = 0; !r && i < rs->md.raid_disks; i++)
if (rs->dev[i].data_dev)
r = fn(ti,
rs->dev[i].data_dev,
0, /* No offset on data devs */
rs->md.dev_sectors,
data);
return r;
}
static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
struct raid_set *rs = ti->private;
unsigned chunk_size = rs->md.chunk_sectors << 9;
struct r5conf *conf = rs->md.private;
blk_limits_io_min(limits, chunk_size);
blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded));
}
static void raid_presuspend(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
md_stop_writes(&rs->md);
}
static void raid_postsuspend(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
mddev_suspend(&rs->md);
}
static void attempt_restore_of_faulty_devices(struct raid_set *rs)
{
int i;
uint64_t failed_devices, cleared_failed_devices = 0;
unsigned long flags;
struct dm_raid_superblock *sb;
struct md_rdev *r;
for (i = 0; i < rs->md.raid_disks; i++) {
r = &rs->dev[i].rdev;
if (test_bit(Faulty, &r->flags) && r->sb_page &&
sync_page_io(r, 0, r->sb_size, r->sb_page, REQ_OP_READ, 0,
1)) {
DMINFO("Faulty %s device #%d has readable super block."
" Attempting to revive it.",
rs->raid_type->name, i);
/*
* Faulty bit may be set, but sometimes the array can
* be suspended before the personalities can respond
* by removing the device from the array (i.e. calling
* 'hot_remove_disk'). If they haven't yet removed
* the failed device, its 'raid_disk' number will be
* '>= 0' - meaning we must call this function
* ourselves.
*/
if ((r->raid_disk >= 0) &&
(r->mddev->pers->hot_remove_disk(r->mddev, r) != 0))
/* Failed to revive this device, try next */
continue;
r->raid_disk = i;
r->saved_raid_disk = i;
flags = r->flags;
clear_bit(Faulty, &r->flags);
clear_bit(WriteErrorSeen, &r->flags);
clear_bit(In_sync, &r->flags);
if (r->mddev->pers->hot_add_disk(r->mddev, r)) {
r->raid_disk = -1;
r->saved_raid_disk = -1;
r->flags = flags;
} else {
r->recovery_offset = 0;
cleared_failed_devices |= 1 << i;
}
}
}
if (cleared_failed_devices) {
rdev_for_each(r, &rs->md) {
sb = page_address(r->sb_page);
failed_devices = le64_to_cpu(sb->failed_devices);
failed_devices &= ~cleared_failed_devices;
sb->failed_devices = cpu_to_le64(failed_devices);
}
}
}
static int __load_dirty_region_bitmap(struct raid_set *rs)
{
int r = 0;
/* Try loading the bitmap unless "raid0", which does not have one */
if (!rs_is_raid0(rs) &&
!test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
r = bitmap_load(&rs->md);
if (r)
DMERR("Failed to load bitmap");
}
return r;
}
static int raid_preresume(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
struct mddev *mddev = &rs->md;
/* This is a resume after a suspend of the set -> it's already started */
if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
return 0;
/*
* The superblocks need to be updated on disk if the
* array is new or __load_dirty_region_bitmap will overwrite them
* in core with old data.
*
* In case the array got modified (takeover/reshape/resize)
* or the data offsets on the component devices changed, they
* have to be updated as well.
*
* Have to switch to readwrite and back in order to
* allow for the superblock updates.
*/
if (test_and_clear_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags)) {
set_bit(MD_CHANGE_DEVS, &mddev->flags);
mddev->ro = 0;
md_update_sb(mddev, 1);
mddev->ro = 1;
}
/*
* Disable/enable discard support on raid set after any
* conversion, because devices can have been added
*/
configure_discard_support(rs);
/* Load the bitmap from disk unless raid0 */
return __load_dirty_region_bitmap(rs);
}
static void raid_resume(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
struct mddev *mddev = &rs->md;
if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
/*
* A secondary resume while the device is active.
* Take this opportunity to check whether any failed
* devices are reachable again.
*/
attempt_restore_of_faulty_devices(rs);
}
mddev->ro = 0;
mddev->in_sync = 0;
clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
if (mddev->suspended)
mddev_resume(mddev);
}
static struct target_type raid_target = {
.name = "raid",
.version = {1, 9, 0},
.module = THIS_MODULE,
.ctr = raid_ctr,
.dtr = raid_dtr,
.map = raid_map,
.status = raid_status,
.message = raid_message,
.iterate_devices = raid_iterate_devices,
.io_hints = raid_io_hints,
.presuspend = raid_presuspend,
.postsuspend = raid_postsuspend,
.preresume = raid_preresume,
.resume = raid_resume,
};
static int __init dm_raid_init(void)
{
DMINFO("Loading target version %u.%u.%u",
raid_target.version[0],
raid_target.version[1],
raid_target.version[2]);
return dm_register_target(&raid_target);
}
static void __exit dm_raid_exit(void)
{
dm_unregister_target(&raid_target);
}
module_init(dm_raid_init);
module_exit(dm_raid_exit);
module_param(devices_handle_discard_safely, bool, 0644);
MODULE_PARM_DESC(devices_handle_discard_safely,
"Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
MODULE_ALIAS("dm-raid0");
MODULE_ALIAS("dm-raid1");
MODULE_ALIAS("dm-raid10");
MODULE_ALIAS("dm-raid4");
MODULE_ALIAS("dm-raid5");
MODULE_ALIAS("dm-raid6");
MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
MODULE_LICENSE("GPL");