[dm-devel] [PATCH 07/11] dm-raid: introduce v1.8.0 extended superblock and new raid types to support takeover/reshaping
heinzm at redhat.com
heinzm at redhat.com
Thu May 19 16:49:30 UTC 2016
From: Heinz Mauelshagen <heinzm at redhat.com>
Add new members to the dm-raid superblock and new raid types to support takeover/reshape.
Add all necessary members supporting takeover and reshape in
one go aiming to limit the amnout of changes to the superblock
layout to planned one.
This is a larger patch due to the new superblock members,
their related flags, validation of both and involved
API additions/changes:
- add additional members to keep track of:
- state about forward/backward reshaping
- reshape position
- new level, layout, stripe size and delta disks
- data offset to current and new data for out-of-place reshapes
- failed devices bitfield extensions to keep track of max raid devices
- adjust super_validate() to cope with new superblock members
- adjust super_init_validation() to cope with new superblock members
- add definitions for ctr flags supporting delta disks etc.
- add new raid types (raid6_n_6 etc.)
- add new raid10 supporting function API (_is_raid10_*())
- adjust to changed raid10 supporting function API
Signed-off-by: Heinz Mauelshagen <heinzm at redhat.com>
---
drivers/md/dm-raid.c | 607 ++++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 475 insertions(+), 132 deletions(-)
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 50bdd7e..3b2bdac 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -63,6 +63,10 @@ struct raid_dev {
#define CTR_FLAG_REGION_SIZE 0x200 /* 2 */ /* Not with raid0! */
#define CTR_FLAG_RAID10_COPIES 0x400 /* 2 */ /* Only with raid10 */
#define CTR_FLAG_RAID10_FORMAT 0x800 /* 2 */ /* Only with raid10 */
+/* New for v1.8.0 */
+#define CTR_FLAG_DELTA_DISKS 0x1000 /* 2 */ /* Only with reshapable raid4/5/6/10! */
+#define CTR_FLAG_DATA_OFFSET 0x2000 /* 2 */ /* Only with reshapable raid4/5/6/10! */
+#define CTR_FLAG_RAID10_USE_NEAR_SETS 0x4000 /* 2 */ /* Only with raid10! */
/*
* Definitions of various constructor flags to
@@ -73,7 +77,8 @@ struct raid_dev {
#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
+#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 | \
@@ -85,7 +90,9 @@ struct raid_dev {
CTR_FLAG_STRIPE_CACHE | \
CTR_FLAG_REGION_SIZE | \
CTR_FLAG_RAID10_COPIES | \
- CTR_FLAG_RAID10_FORMAT)
+ CTR_FLAG_RAID10_FORMAT | \
+ CTR_FLAG_DELTA_DISKS | \
+ CTR_FLAG_DATA_OFFSET)
/* All ctr optional arguments */
#define ALL_CTR_FLAGS (CTR_FLAG_OPTIONS_NO_ARGS | \
@@ -99,7 +106,9 @@ struct raid_dev {
/* "raid1" does not accept stripe cache or any raid10 options */
#define RAID1_INVALID_FLAGS (CTR_FLAG_STRIPE_CACHE | \
CTR_FLAG_RAID10_COPIES | \
- CTR_FLAG_RAID10_FORMAT)
+ CTR_FLAG_RAID10_FORMAT | \
+ CTR_FLAG_DELTA_DISKS | \
+ CTR_FLAG_DATA_OFFSET)
/* "raid10" does not accept any raid1 or stripe cache options */
#define RAID10_INVALID_FLAGS (CTR_FLAG_WRITE_MOSTLY | \
@@ -115,16 +124,24 @@ struct raid_dev {
#define RAID45_INVALID_FLAGS (CTR_FLAG_WRITE_MOSTLY | \
CTR_FLAG_MAX_WRITE_BEHIND | \
CTR_FLAG_RAID10_FORMAT | \
- CTR_FLAG_RAID10_COPIES)
+ CTR_FLAG_RAID10_COPIES | \
+ CTR_FLAG_RAID10_USE_NEAR_SETS)
#define RAID6_INVALID_FLAGS (CTR_FLAG_NOSYNC | RAID45_INVALID_FLAGS)
/* ...invalid options definitions per raid level */
+/* 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)
+
struct raid_set {
struct dm_target *ti;
uint32_t bitmap_loaded;
uint32_t ctr_flags;
+ int raid_disks;
+ int delta_disks;
+ int raid10_copies;
+
struct mddev md;
struct raid_type *raid_type;
struct dm_target_callbacks callbacks;
@@ -132,6 +149,12 @@ struct raid_set {
struct raid_dev dev[0];
};
+/* 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. */
@@ -141,17 +164,26 @@ static struct raid_type {
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", "RAID10 (striped mirrors)", 0, 2, 10, UINT_MAX /* Varies */},
- {"raid4", "RAID4 (dedicated parity disk)", 1, 2, 5, ALGORITHM_PARITY_0},
- {"raid5_la", "RAID5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC},
- {"raid5_ra", "RAID5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC},
- {"raid5_ls", "RAID5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC},
- {"raid5_rs", "RAID5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC},
- {"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}
+ {"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] */
@@ -228,6 +260,23 @@ static const char *_argname_by_flag(const uint32_t flag)
}
/*
+ * 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
*/
@@ -316,57 +365,184 @@ static int rs_check_for_invalid_flags(struct raid_set *rs)
return 0;
}
-static char *raid10_md_layout_to_format(int layout)
+
+/* 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 and 17 stand for "offset" and "use_far_sets"
+ * Bit 16 stands for "offset"
+ * (i.e. adjacent stripes hold copies)
+ *
* Refer to MD's raid10.c for details
*/
- if ((layout & 0x10000) && (layout & 0x20000))
+ if (_is_raid10_offset(layout))
return "offset";
- if ((layout & 0xFF) > 1)
+ if (_raid10_near_copies(layout) > 1)
return "near";
+ WARN_ON(_raid10_far_copies(layout) < 2);
+
return "far";
}
-static unsigned raid10_md_layout_to_copies(int layout)
+/* 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)
{
- if ((layout & 0xFF) > 1)
- return layout & 0xFF;
- return (layout >> 8) & 0xFF;
+ return _raid10_near_copies(layout) > 1 ?
+ _raid10_near_copies(layout) : _raid10_far_copies(layout);
}
-static int raid10_format_to_md_layout(char *format, unsigned copies)
+/* 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 n = 1, f = 1;
+ unsigned int n = 1, f = 1, r = 0;
- if (!strcasecmp("near", format))
+ /*
+ * 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
+
+ else if (algorithm == ALGORITHM_RAID10_OFFSET) {
+ f = copies;
+ r = RAID10_OFFSET;
+ if (!_test_flag(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_flag(CTR_FLAG_RAID10_USE_NEAR_SETS, rs->ctr_flags))
+ r |= RAID10_USE_FAR_SETS;
- if (!strcasecmp("offset", format))
- return 0x30000 | (f << 8) | n;
+ } else
+ return -EINVAL;
- if (!strcasecmp("far", format))
- return 0x20000 | (f << 8) | n;
+ 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 (f << 8) | n;
+ return 0;
}
+/* Return raid_type for @name */
static struct raid_type *get_raid_type(const char *name)
{
- int i;
+ struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
+
+ while (rtp-- > raid_types)
+ if (!strcasecmp(rtp->name, name))
+ return rtp;
+
+ return NULL;
+}
- for (i = 0; i < ARRAY_SIZE(raid_types); i++)
- if (!strcmp(raid_types[i].name, name))
- return &raid_types[i];
+/* 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 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->delta_disks = 0;
+}
+
+
static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *raid_type, unsigned raid_devs)
{
unsigned i;
@@ -381,6 +557,9 @@ static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *ra
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;
@@ -712,7 +891,7 @@ too_many:
static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
unsigned num_raid_params)
{
- char *raid10_format = "near";
+ int raid10_format = ALGORITHM_RAID10_DEFAULT;
unsigned raid10_copies = 2;
unsigned i;
unsigned value, region_size = 0;
@@ -720,6 +899,7 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
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 */
@@ -731,7 +911,7 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
* First, parse the in-order required arguments
* "chunk_size" is the only argument of this type.
*/
- if (rt_is_raid1(rs->raid_type)) {
+ if (rt_is_raid1(rt)) {
if (value)
DMERR("Ignoring chunk size parameter for RAID 1");
value = 0;
@@ -796,14 +976,11 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
if (!strcasecmp(key, _argname_by_flag(CTR_FLAG_RAID10_FORMAT))) {
if (_test_and_set_flag(CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
return ti_error_einval(rs->ti, "Only one raid10_format argument pair allowed");
- if (!rt_is_raid10(rs->raid_type))
+ if (!rt_is_raid10(rt))
return ti_error_einval(rs->ti, "'raid10_format' is an invalid parameter for this RAID type");
- if (strcmp("near", arg) &&
- strcmp("far", arg) &&
- strcmp("offset", arg))
- return ti_error_einval(rs->ti, "Invalid 'raid10_format' value given");
-
- raid10_format = (char *) arg;
+ raid10_format = raid10_name_to_format(arg);
+ if (raid10_format < 0)
+ return ti_error_ret(rs->ti, "Invalid 'raid10_format' value given", raid10_format);
continue;
}
@@ -825,7 +1002,7 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
rd->rdev.recovery_offset = 0;
_set_flag(CTR_FLAG_REBUILD, &rs->ctr_flags);
} else if (!strcasecmp(key, _argname_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
- if (!rt_is_raid1(rs->raid_type))
+ if (!rt_is_raid1(rt))
return ti_error_einval(rs->ti, "write_mostly option is only valid for RAID1");
if (!_in_range(value, 0, rs->md.raid_disks - 1))
@@ -834,7 +1011,7 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
set_bit(WriteMostly, &rs->dev[value].rdev.flags);
_set_flag(CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
} else if (!strcasecmp(key, _argname_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
- if (!rt_is_raid1(rs->raid_type))
+ if (!rt_is_raid1(rt))
return ti_error_einval(rs->ti, "max_write_behind option is only valid for RAID1");
if (_test_and_set_flag(CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
@@ -864,7 +1041,7 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
*/
value /= 2;
- if (!rt_is_raid456(rs->raid_type))
+ if (!rt_is_raid456(rt))
return ti_error_einval(rs->ti, "Inappropriate argument: stripe_cache");
if (raid5_set_cache_size(&rs->md, (int)value))
return ti_error_einval(rs->ti, "Bad stripe_cache size");
@@ -911,29 +1088,35 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
if (dm_set_target_max_io_len(rs->ti, max_io_len))
return -EINVAL;
- if (rt_is_raid10(rs->raid_type)) {
+ if (rt_is_raid10(rt)) {
if (raid10_copies > rs->md.raid_disks)
return ti_error_einval(rs->ti, "Not enough devices to satisfy specification");
- /*
- * If the format is not "near", we only support
- * two copies at the moment.
- */
- if (strcmp("near", raid10_format) && (raid10_copies > 2))
- return ti_error_einval(rs->ti, "Too many copies for given RAID10 format.");
+ rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
+ if (rs->md.new_layout < 0)
+ return ti_error_ret(rs->ti, "Error getting raid10 format", rs->md.new_layout);
+
+ rt = get_raid_type_by_ll(10, rs->md.new_layout);
+ if (!rt)
+ return ti_error_einval(rs->ti, "Failed to recognize new raid10 layout");
+
+ if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
+ rt->algorithm == ALGORITHM_RAID10_NEAR) &&
+ _test_flag(CTR_FLAG_RAID10_USE_NEAR_SETS, rs->ctr_flags))
+ return ti_error_einval(rs->ti, "RAID10 format \"near\" and \"raid10_use_near_sets\" are incompatible");
/* (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(raid10_format,
- raid10_copies);
+ 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(rs->raid_type) &&
+ } else if (!rt_is_raid1(rt) &&
sector_div(sectors_per_dev,
- (rs->md.raid_disks - rs->raid_type->parity_devs)))
+ (rs->md.raid_disks - rt->parity_devs)))
return ti_error_einval(rs->ti, "Target length not divisible by number of data devices");
+ rs->raid10_copies = raid10_copies;
rs->md.dev_sectors = sectors_per_dev;
/* Assume there are no metadata devices until the drives are parsed */
@@ -958,6 +1141,13 @@ static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
return mddev_congested(&rs->md, bits);
}
+/* Features */
+#define FEATURE_FLAG_SUPPORTS_RESHAPE 0x1
+
+/* 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.
@@ -965,13 +1155,14 @@ static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
#define DM_RAID_MAGIC 0x64526D44
struct dm_raid_superblock {
__le32 magic; /* "DmRd" */
- __le32 features; /* Used to indicate possible future changes */
+ __le32 compat_features; /* Used to indicate compatible features (like 1.8.0 ondisk metadata extension) */
- __le32 num_devices; /* Number of devices in this array. (Max 64) */
- __le32 array_position; /* The position of this drive in the array */
+ __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; /* Bit field of devices to indicate failures */
+ __le64 failed_devices; /* Pre 1.8.0 part of bit field of devices to */
+ /* indicate failures (see extension below) */
/*
* This offset tracks the progress of the repair or replacement of
@@ -980,19 +1171,62 @@ struct dm_raid_superblock {
__le64 disk_recovery_offset;
/*
- * This offset tracks the progress of the initial array
+ * This offset tracks the progress of the initial raid set
* synchronisation/parity calculation.
*/
__le64 array_resync_offset;
/*
- * RAID characteristics
+ * raid characteristics
*/
__le32 level;
__le32 layout;
__le32 stripe_sectors;
- /* Remainder of a logical block is zero-filled when writing (see super_sync()). */
+ /********************************************************************
+ * BELOW FOLLOW V1.8.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
+ *
+ * FEATURE_FLAG_SUPPORTS_RESHAPE 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 1.8.0 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)
@@ -1032,7 +1266,7 @@ static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
sb->magic = cpu_to_le32(DM_RAID_MAGIC);
- sb->features = cpu_to_le32(0); /* No features yet */
+ sb->compat_features = cpu_to_le32(0); /* No features yet */
sb->num_devices = cpu_to_le32(mddev->raid_disks);
sb->array_position = cpu_to_le32(rdev->raid_disk);
@@ -1105,119 +1339,210 @@ static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
return (events_sb > events_refsb) ? 1 : 0;
}
-static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev)
+/* Helper to retrieve all failed devices bits from @sb */
+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 (_test_flag(FEATURE_FLAG_SUPPORTS_RESHAPE, le32_to_cpu(sb->compat_features))) {
+ int i = ARRAY_SIZE(sb->extended_failed_devices);
+
+ while (i--)
+ failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
+ }
+}
+
+static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
{
int role;
- struct raid_set *rs = container_of(mddev, struct raid_set, md);
+ unsigned int d;
+ struct mddev *mddev = &rs->md;
uint64_t events_sb;
- uint64_t failed_devices;
+ uint64_t failed_devices[DISKS_ARRAY_ELEMS];
struct dm_raid_superblock *sb;
- uint32_t new_devs = 0;
- uint32_t rebuilds = 0;
+ 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);
- failed_devices = le64_to_cpu(sb->failed_devices);
/*
* Initialise to 1 if this is a new superblock.
*/
mddev->events = events_sb ? : 1;
+ mddev->reshape_position = MaxSector;
+
/*
- * Reshaping is not currently allowed
+ * Reshaping is supported, e.g. reshape_position is valid
+ * in superblock and superblock content is authoritative.
*/
- if (le32_to_cpu(sb->level) != mddev->level) {
- DMERR("Reshaping arrays not yet supported. (RAID level change)");
- return -EINVAL;
- }
- if (le32_to_cpu(sb->layout) != mddev->layout) {
- DMERR("Reshaping arrays 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 arrays not yet supported. (stripe sectors change)");
- return -EINVAL;
- }
+ if (_test_flag(FEATURE_FLAG_SUPPORTS_RESHAPE, le32_to_cpu(sb->compat_features))) {
+ /* 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 (_test_flag(SB_FLAG_RESHAPE_ACTIVE, le32_to_cpu(sb->flags))) {
+ if (_test_flag(CTR_FLAG_DELTA_DISKS, rs->ctr_flags)) {
+ DMERR("Reshape requested but raid set is still reshaping");
+ return -EINVAL;
+ }
- /* We can only change the number of devices in RAID1 right now */
- if (!rt_is_raid1(rs->raid_type) &&
- (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) {
- DMERR("Reshaping arrays not yet supported. (device count change)");
- return -EINVAL;
+ if (mddev->delta_disks < 0 ||
+ (!mddev->delta_disks && _test_flag(SB_FLAG_RESHAPE_BACKWARDS, le32_to_cpu(sb->flags))))
+ 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 {
+ /*
+ * Reshaping is not allowed, because we don't have the appropriate 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_flags(CTR_FLAGS_ANY_SYNC, rs->ctr_flags)))
+ if (!_test_flag(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 array is brand new - in which case, all of the
+ * 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 array
+ * 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);
+ DMINFO("Device %d specified for rebuild; clearing superblock",
+ r->raid_disk);
rebuilds++;
- } else if (test_bit(FirstUse, &r->flags))
- new_devs++;
+
+ if (test_bit(FirstUse, &r->flags))
+ rebuild_and_new++;
+ }
+
+ d++;
}
- if (!rebuilds) {
- if (new_devs == mddev->raid_disks) {
- DMINFO("Superblocks created for new array");
+ 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);
- } else if (new_devs) {
- DMERR("New device injected "
- "into existing array without 'rebuild' "
- "parameter specified");
+ 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) {
- DMERR("'rebuild' devices cannot be "
- "injected into an array with other first-time devices");
- return -EINVAL;
- } else if (mddev->recovery_cp != MaxSector) {
- DMERR("'rebuild' specified while array is not in-sync");
+ } 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 w/o '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 (!rt_is_raid1(rs->raid_type))
- return ti_error_einval(rs->ti, "Cannot change device "
- "positions in RAID array");
- DMINFO("RAID1 device #%d now at position #%d",
+ if (_is_raid10_near(mddev->layout)) {
+ if (mddev->raid_disks % _raid10_near_copies(mddev->layout) ||
+ rs->raid_disks % rs->raid10_copies)
+ return ti_error_einval(rs->ti, "Cannot change raid10 near "
+ "set to odd # of devices!");
+
+ 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))
+ return ti_error_einval(rs->ti, "Cannot change device positions in raid set");
+
+ DMINFO("raid device #%d now at position #%d",
role, r->raid_disk);
}
@@ -1225,7 +1550,7 @@ static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev)
* Partial recovery is performed on
* returning failed devices.
*/
- if (failed_devices & (1 << role))
+ if (test_bit(role, (void *) failed_devices))
set_bit(Faulty, &r->flags);
}
}
@@ -1236,36 +1561,54 @@ static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev)
static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
{
struct mddev *mddev = &rs->md;
- struct dm_raid_superblock *sb = page_address(rdev->sb_page);
+ struct dm_raid_superblock *sb;
+
+ if (!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(mddev, rdev))
+ if (!mddev->events && super_init_validation(rs, rdev))
return -EINVAL;
+ if (sb->compat_features || sb->incompat_features) /* No features supported yet */
+ return ti_error_einval(rs->ti, "Unable to assemble array: No feature flags supported yet");
+
/* 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_bit(FirstUse, &rdev->flags)) {
+
+ 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)
- clear_bit(In_sync, &rdev->flags);
+ 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_bit(Faulty, &rdev->flags)) {
- clear_bit(Faulty, &rdev->flags);
+ 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;
- rdev->recovery_offset = 0;
}
- clear_bit(FirstUse, &rdev->flags);
+ /* 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;
}
--
2.5.5
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