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-rw-r--r--drivers/md/dm-raid.c4112
1 files changed, 4112 insertions, 0 deletions
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
new file mode 100644
index 000000000..4b7528dc2
--- /dev/null
+++ b/drivers/md/dm-raid.c
@@ -0,0 +1,4112 @@
+/*
+ * Copyright (C) 2010-2011 Neil Brown
+ * Copyright (C) 2010-2018 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 "md-bitmap.h"
+
+#include <linux/device-mapper.h>
+
+#define DM_MSG_PREFIX "raid"
+#define MAX_RAID_DEVICES 253 /* md-raid kernel limit */
+
+/*
+ * Minimum sectors of free reshape space per raid device
+ */
+#define MIN_FREE_RESHAPE_SPACE to_sector(4*4096)
+
+/*
+ * Minimum journal space 4 MiB in sectors.
+ */
+#define MIN_RAID456_JOURNAL_SPACE (4*2048)
+
+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 raid1/4/5/6/10! */
+#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! */
+
+/* New for v1.10.0 */
+#define __CTR_FLAG_JOURNAL_DEV 15 /* 2 */ /* Only with raid4/5/6 (journal device)! */
+
+/* New for v1.11.1 */
+#define __CTR_FLAG_JOURNAL_MODE 16 /* 2 */ /* Only with raid4/5/6 (journal mode)! */
+
+/*
+ * 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)
+#define CTR_FLAG_JOURNAL_DEV (1 << __CTR_FLAG_JOURNAL_DEV)
+#define CTR_FLAG_JOURNAL_MODE (1 << __CTR_FLAG_JOURNAL_MODE)
+
+/*
+ * 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 | \
+ CTR_FLAG_JOURNAL_DEV | \
+ CTR_FLAG_JOURNAL_MODE)
+
+/* 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_DELTA_DISKS | \
+ 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_STRIPE_CACHE | \
+ CTR_FLAG_REGION_SIZE | \
+ CTR_FLAG_DELTA_DISKS | \
+ CTR_FLAG_DATA_OFFSET | \
+ CTR_FLAG_JOURNAL_DEV | \
+ CTR_FLAG_JOURNAL_MODE)
+
+#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_STRIPE_CACHE | \
+ CTR_FLAG_REGION_SIZE | \
+ CTR_FLAG_DELTA_DISKS | \
+ CTR_FLAG_DATA_OFFSET | \
+ CTR_FLAG_JOURNAL_DEV | \
+ CTR_FLAG_JOURNAL_MODE)
+/* ...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 0
+#define RT_FLAG_RS_RESUMED 1
+#define RT_FLAG_RS_BITMAP_LOADED 2
+#define RT_FLAG_UPDATE_SBS 3
+#define RT_FLAG_RESHAPE_RS 4
+#define RT_FLAG_RS_SUSPENDED 5
+#define RT_FLAG_RS_IN_SYNC 6
+#define RT_FLAG_RS_RESYNCING 7
+#define RT_FLAG_RS_GROW 8
+
+/* Array elements of 64 bit needed for rebuild/failed disk 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 stripe_cache_entries;
+ 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;
+ int requested_bitmap_chunk_sectors;
+
+ struct mddev md;
+ struct raid_type *raid_type;
+
+ sector_t array_sectors;
+ sector_t dev_sectors;
+
+ /* Optional raid4/5/6 journal device */
+ struct journal_dev {
+ struct dm_dev *dev;
+ struct md_rdev rdev;
+ int mode;
+ } journal_dev;
+
+ struct raid_dev dev[];
+};
+
+static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)
+{
+ struct mddev *mddev = &rs->md;
+
+ 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 rs_layout *l)
+{
+ struct mddev *mddev = &rs->md;
+
+ 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 int parity_devs; /* # of parity devices. */
+ const unsigned int minimal_devs;/* minimal # of devices in set. */
+ const unsigned int level; /* RAID level. */
+ const unsigned int 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 first parity disk)", 1, 2, 5, ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */
+ {"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, "write_mostly"},
+ { 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"},
+ { CTR_FLAG_JOURNAL_DEV, "journal_dev" },
+ { CTR_FLAG_JOURNAL_MODE, "journal_mode" },
+};
+
+/* 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;
+}
+
+/* Define correlation of raid456 journal cache modes and dm-raid target line parameters */
+static struct {
+ const int mode;
+ const char *param;
+} _raid456_journal_mode[] = {
+ { R5C_JOURNAL_MODE_WRITE_THROUGH , "writethrough" },
+ { R5C_JOURNAL_MODE_WRITE_BACK , "writeback" }
+};
+
+/* Return MD raid4/5/6 journal mode for dm @journal_mode one */
+static int dm_raid_journal_mode_to_md(const char *mode)
+{
+ int m = ARRAY_SIZE(_raid456_journal_mode);
+
+ while (m--)
+ if (!strcasecmp(mode, _raid456_journal_mode[m].param))
+ return _raid456_journal_mode[m].mode;
+
+ return -EINVAL;
+}
+
+/* Return dm-raid raid4/5/6 journal mode string for @mode */
+static const char *md_journal_mode_to_dm_raid(const int mode)
+{
+ int m = ARRAY_SIZE(_raid456_journal_mode);
+
+ while (m--)
+ if (mode == _raid456_journal_mode[m].mode)
+ return _raid456_journal_mode[m].param;
+
+ return "unknown";
+}
+
+/*
+ * Bool helpers to test for various raid levels of a raid set.
+ * 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 raid1 */
+static bool rs_is_raid1(struct raid_set *rs)
+{
+ return rs->md.level == 1;
+}
+
+/* Return true, if raid set in @rs is raid10 */
+static bool rs_is_raid10(struct raid_set *rs)
+{
+ return rs->md.level == 10;
+}
+
+/* Return true, if raid set in @rs is level 6 */
+static bool rs_is_raid6(struct raid_set *rs)
+{
+ return rs->md.level == 6;
+}
+
+/* Return true, if raid set in @rs is level 4, 5 or 6 */
+static bool rs_is_raid456(struct raid_set *rs)
+{
+ return __within_range(rs->md.level, 4, 6);
+}
+
+/* Return true, if raid set in @rs is reshapable */
+static bool __is_raid10_far(int layout);
+static bool rs_is_reshapable(struct raid_set *rs)
+{
+ return rs_is_raid456(rs) ||
+ (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
+}
+
+/* Return true, if raid set in @rs is recovering */
+static bool rs_is_recovering(struct raid_set *rs)
+{
+ return rs->md.recovery_cp < rs->md.dev_sectors;
+}
+
+/* Return true, if raid set in @rs is reshaping */
+static bool rs_is_reshaping(struct raid_set *rs)
+{
+ return rs->md.reshape_position != MaxSector;
+}
+
+/*
+ * bool helpers to test for various raid levels of a raid type @rt
+ */
+
+/* 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 bool __is_raid10_offset(int layout)
+{
+ return !!(layout & RAID10_OFFSET);
+}
+
+/* Return true if md raid10 near for @layout */
+static bool __is_raid10_near(int layout)
+{
+ return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
+}
+
+/* Return true if md raid10 far for @layout */
+static bool __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";
+
+ if (__raid10_far_copies(layout) > 1)
+ return "far";
+
+ return "unknown";
+}
+
+/* Return md raid10 algorithm for @name */
+static 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 max(__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;
+ 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 bool __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 false;
+}
+
+/* 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;
+}
+
+/* Adjust rdev sectors */
+static void rs_set_rdev_sectors(struct raid_set *rs)
+{
+ struct mddev *mddev = &rs->md;
+ struct md_rdev *rdev;
+
+ /*
+ * raid10 sets rdev->sector to the device size, which
+ * is unintended in case of out-of-place reshaping
+ */
+ rdev_for_each(rdev, mddev)
+ if (!test_bit(Journal, &rdev->flags))
+ rdev->sectors = mddev->dev_sectors;
+}
+
+/*
+ * Change bdev capacity of @rs in case of a disk add/remove reshape
+ */
+static void rs_set_capacity(struct raid_set *rs)
+{
+ struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
+
+ set_capacity_and_notify(gendisk, rs->md.array_sectors);
+}
+
+/*
+ * 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 int raid_devs)
+{
+ unsigned int i;
+ struct raid_set *rs;
+
+ if (raid_devs <= raid_type->parity_devs) {
+ ti->error = "Insufficient number of devices";
+ return ERR_PTR(-EINVAL);
+ }
+
+ rs = kzalloc(struct_size(rs, dev, raid_devs), 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->stripe_cache_entries = 256;
+ 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 = MaxSector;
+
+ 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;
+}
+
+/* Free all @rs allocations */
+static void raid_set_free(struct raid_set *rs)
+{
+ int i;
+
+ if (rs->journal_dev.dev) {
+ md_rdev_clear(&rs->journal_dev.rdev);
+ dm_put_device(rs->ti, rs->journal_dev.dev);
+ }
+
+ for (i = 0; i < rs->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->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 initially.
+ * Out of place reshape will set them accordingly.
+ */
+ rs->dev[i].rdev.data_offset = 0;
+ rs->dev[i].rdev.new_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 (rs->journal_dev.dev)
+ list_add_tail(&rs->journal_dev.rdev.same_set, &rs->md.disks);
+
+ 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 (rs_is_raid0(rs))
+ return 0;
+
+ 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 = to_bytes(region_size);
+
+ 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 int i, rebuild_cnt = 0;
+ unsigned int rebuilds_per_group = 0, copies, raid_disks;
+ unsigned int group_size, last_group_start;
+
+ for (i = 0; i < rs->raid_disks; i++)
+ if (!test_bit(FirstUse, &rs->dev[i].rdev.flags) &&
+ ((!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
+ !rs->dev[i].rdev.sb_page)))
+ rebuild_cnt++;
+
+ switch (rs->md.level) {
+ case 0:
+ break;
+ 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.new_layout);
+ if (copies < 2) {
+ DMERR("Bogus raid10 data copies < 2!");
+ return -EINVAL;
+ }
+
+ 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
+ */
+ raid_disks = min(rs->raid_disks, rs->md.raid_disks);
+ if (__is_raid10_near(rs->md.new_layout)) {
+ for (i = 0; i < raid_disks; i++) {
+ if (!(i % copies))
+ 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;
+ }
+
+ /*
+ * 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 = (raid_disks / copies);
+ last_group_start = (raid_disks / group_size) - 1;
+ last_group_start *= group_size;
+ for (i = 0; i < 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
+ * [journal_dev <dev>] raid4/5/6 journaling deviice
+ * (i.e. write hole closing log)
+ *
+ * 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 int num_raid_params)
+{
+ int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
+ unsigned int raid10_copies = 2;
+ unsigned int i, write_mostly = 0;
+ unsigned int region_size = 0;
+ 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 (kstrtoint(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->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;
+ }
+ 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;
+ }
+ 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.
+ */
+ /* "raid10_format {near|offset|far} */
+ 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;
+ }
+
+ /* "journal_dev <dev>" */
+ if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV))) {
+ int r;
+ struct md_rdev *jdev;
+
+ if (test_and_set_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
+ rs->ti->error = "Only one raid4/5/6 set journaling device allowed";
+ return -EINVAL;
+ }
+ if (!rt_is_raid456(rt)) {
+ rs->ti->error = "'journal_dev' is an invalid parameter for this RAID type";
+ return -EINVAL;
+ }
+ r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
+ &rs->journal_dev.dev);
+ if (r) {
+ rs->ti->error = "raid4/5/6 journal device lookup failure";
+ return r;
+ }
+ jdev = &rs->journal_dev.rdev;
+ md_rdev_init(jdev);
+ jdev->mddev = &rs->md;
+ jdev->bdev = rs->journal_dev.dev->bdev;
+ jdev->sectors = bdev_nr_sectors(jdev->bdev);
+ if (jdev->sectors < MIN_RAID456_JOURNAL_SPACE) {
+ rs->ti->error = "No space for raid4/5/6 journal";
+ return -ENOSPC;
+ }
+ rs->journal_dev.mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
+ set_bit(Journal, &jdev->flags);
+ continue;
+ }
+
+ /* "journal_mode <mode>" ("journal_dev" mandatory!) */
+ if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE))) {
+ int r;
+
+ if (!test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
+ rs->ti->error = "raid4/5/6 'journal_mode' is invalid without 'journal_dev'";
+ return -EINVAL;
+ }
+ if (test_and_set_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
+ rs->ti->error = "Only one raid4/5/6 'journal_mode' argument allowed";
+ return -EINVAL;
+ }
+ r = dm_raid_journal_mode_to_md(arg);
+ if (r < 0) {
+ rs->ti->error = "Invalid 'journal_mode' argument";
+ return r;
+ }
+ rs->journal_dev.mode = r;
+ continue;
+ }
+
+ /*
+ * Parameters with number values from here on.
+ */
+ if (kstrtoint(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;
+ }
+
+ write_mostly++;
+ 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
+ */
+ if (value < 0 || value / 2 > COUNTER_MAX) {
+ rs->ti->error = "Max write-behind limit out of range";
+ return -EINVAL;
+ }
+
+ rs->md.bitmap_info.max_write_behind = value / 2;
+ } 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 < 0) {
+ 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 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 ||
+ (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {
+ 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;
+ }
+
+ if (!rt_is_raid456(rt)) {
+ rs->ti->error = "Inappropriate argument: stripe_cache";
+ return -EINVAL;
+ }
+
+ if (value < 0) {
+ rs->ti->error = "Bogus stripe cache entries value";
+ return -EINVAL;
+ }
+ rs->stripe_cache_entries = value;
+ } 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 < 0) {
+ rs->ti->error = "min_recovery_rate out of range";
+ return -EINVAL;
+ }
+ rs->md.sync_speed_min = value;
+ } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
+ if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
+ rs->ti->error = "Only one max_recovery_rate argument pair allowed";
+ return -EINVAL;
+ }
+
+ if (value < 0) {
+ rs->ti->error = "max_recovery_rate out of range";
+ return -EINVAL;
+ }
+ rs->md.sync_speed_max = 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;
+ rs->requested_bitmap_chunk_sectors = 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 (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
+ test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
+ rs->ti->error = "sync and nosync are mutually exclusive";
+ return -EINVAL;
+ }
+
+ if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
+ (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
+ test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
+ rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
+ return -EINVAL;
+ }
+
+ if (write_mostly >= rs->md.raid_disks) {
+ rs->ti->error = "Can't set all raid1 devices to write_mostly";
+ return -EINVAL;
+ }
+
+ if (rs->md.sync_speed_max &&
+ rs->md.sync_speed_min > rs->md.sync_speed_max) {
+ rs->ti->error = "Bogus recovery rates";
+ 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;
+ }
+ }
+
+ rs->raid10_copies = raid10_copies;
+
+ /* 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);
+}
+
+/* Set raid4/5/6 cache size */
+static int rs_set_raid456_stripe_cache(struct raid_set *rs)
+{
+ int r;
+ struct r5conf *conf;
+ struct mddev *mddev = &rs->md;
+ uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
+ uint32_t nr_stripes = rs->stripe_cache_entries;
+
+ if (!rt_is_raid456(rs->raid_type)) {
+ rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
+ return -EINVAL;
+ }
+
+ if (nr_stripes < min_stripes) {
+ DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
+ nr_stripes, min_stripes);
+ nr_stripes = min_stripes;
+ }
+
+ conf = mddev->private;
+ if (!conf) {
+ rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
+ return -EINVAL;
+ }
+
+ /* Try setting number of stripes in raid456 stripe cache */
+ if (conf->min_nr_stripes != nr_stripes) {
+ r = raid5_set_cache_size(mddev, nr_stripes);
+ if (r) {
+ rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
+ return r;
+ }
+
+ DMINFO("%u stripe cache entries", nr_stripes);
+ }
+
+ return 0;
+}
+
+/* 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;
+}
+
+/* Return # of data stripes of @rs (i.e. as of ctr) */
+static unsigned int rs_data_stripes(struct raid_set *rs)
+{
+ return rs->raid_disks - rs->raid_type->parity_devs;
+}
+
+/*
+ * Retrieve rdev->sectors from any valid raid device of @rs
+ * to allow userpace to pass in arbitray "- -" device tupples.
+ */
+static sector_t __rdev_sectors(struct raid_set *rs)
+{
+ int i;
+
+ for (i = 0; i < rs->raid_disks; i++) {
+ struct md_rdev *rdev = &rs->dev[i].rdev;
+
+ if (!test_bit(Journal, &rdev->flags) &&
+ rdev->bdev && rdev->sectors)
+ return rdev->sectors;
+ }
+
+ return 0;
+}
+
+/* Check that calculated dev_sectors fits all component devices. */
+static int _check_data_dev_sectors(struct raid_set *rs)
+{
+ sector_t ds = ~0;
+ struct md_rdev *rdev;
+
+ rdev_for_each(rdev, &rs->md)
+ if (!test_bit(Journal, &rdev->flags) && rdev->bdev) {
+ ds = min(ds, bdev_nr_sectors(rdev->bdev));
+ if (ds < rs->md.dev_sectors) {
+ rs->ti->error = "Component device(s) too small";
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+/* Calculate the sectors per device and per array used for @rs */
+static int rs_set_dev_and_array_sectors(struct raid_set *rs, sector_t sectors, bool use_mddev)
+{
+ int delta_disks;
+ unsigned int data_stripes;
+ sector_t array_sectors = sectors, dev_sectors = sectors;
+ struct mddev *mddev = &rs->md;
+
+ if (use_mddev) {
+ delta_disks = mddev->delta_disks;
+ data_stripes = mddev_data_stripes(rs);
+ } else {
+ delta_disks = rs->delta_disks;
+ data_stripes = rs_data_stripes(rs);
+ }
+
+ /* Special raid1 case w/o delta_disks support (yet) */
+ if (rt_is_raid1(rs->raid_type))
+ ;
+ else if (rt_is_raid10(rs->raid_type)) {
+ if (rs->raid10_copies < 2 ||
+ delta_disks < 0) {
+ rs->ti->error = "Bogus raid10 data copies or delta disks";
+ return -EINVAL;
+ }
+
+ dev_sectors *= rs->raid10_copies;
+ if (sector_div(dev_sectors, data_stripes))
+ goto bad;
+
+ array_sectors = (data_stripes + delta_disks) * dev_sectors;
+ if (sector_div(array_sectors, rs->raid10_copies))
+ goto bad;
+
+ } else if (sector_div(dev_sectors, data_stripes))
+ goto bad;
+
+ else
+ /* Striped layouts */
+ array_sectors = (data_stripes + delta_disks) * dev_sectors;
+
+ mddev->array_sectors = array_sectors;
+ mddev->dev_sectors = dev_sectors;
+ rs_set_rdev_sectors(rs);
+
+ return _check_data_dev_sectors(rs);
+bad:
+ rs->ti->error = "Target length not divisible by number of data devices";
+ return -EINVAL;
+}
+
+/* Setup recovery on @rs */
+static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
+{
+ /* raid0 does not recover */
+ if (rs_is_raid0(rs))
+ rs->md.recovery_cp = MaxSector;
+ /*
+ * A raid6 set has to be recovered either
+ * completely or for the grown part to
+ * ensure proper parity and Q-Syndrome
+ */
+ else if (rs_is_raid6(rs))
+ rs->md.recovery_cp = dev_sectors;
+ /*
+ * Other raid set types may skip recovery
+ * depending on the 'nosync' flag.
+ */
+ else
+ rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
+ ? MaxSector : dev_sectors;
+}
+
+static void do_table_event(struct work_struct *ws)
+{
+ struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
+
+ smp_rmb(); /* Make sure we access most actual mddev properties */
+ if (!rs_is_reshaping(rs)) {
+ if (rs_is_raid10(rs))
+ rs_set_rdev_sectors(rs);
+ rs_set_capacity(rs);
+ }
+ dm_table_event(rs->ti->table);
+}
+
+/*
+ * 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.
+ */
+static int rs_check_takeover(struct raid_set *rs)
+{
+ struct mddev *mddev = &rs->md;
+ unsigned int near_copies;
+
+ if (rs->md.degraded) {
+ rs->ti->error = "Can't takeover degraded raid set";
+ return -EPERM;
+ }
+
+ if (rs_is_reshaping(rs)) {
+ rs->ti->error = "Can't takeover reshaping raid set";
+ return -EPERM;
+ }
+
+ 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 % mddev->raid_disks))
+ 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_* -> raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
+ 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 Q-Syndrome 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;
+ break;
+
+ 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;
+}
+
+/* True if layout is set to reshape. */
+static bool rs_is_layout_change(struct raid_set *rs, bool use_mddev)
+{
+ return (use_mddev ? rs->md.delta_disks : rs->delta_disks) ||
+ rs->md.new_layout != rs->md.layout ||
+ rs->md.new_chunk_sectors != rs->md.chunk_sectors;
+}
+
+/* True if @rs is requested to reshape by ctr */
+static bool rs_reshape_requested(struct raid_set *rs)
+{
+ bool change;
+ struct mddev *mddev = &rs->md;
+
+ if (rs_takeover_requested(rs))
+ return false;
+
+ if (rs_is_raid0(rs))
+ return false;
+
+ change = rs_is_layout_change(rs, false);
+
+ /* Historical case to support raid1 reshape without delta disks */
+ if (rs_is_raid1(rs)) {
+ if (rs->delta_disks)
+ return !!rs->delta_disks;
+
+ return !change &&
+ mddev->raid_disks != rs->raid_disks;
+ }
+
+ if (rs_is_raid10(rs))
+ return change &&
+ !__is_raid10_far(mddev->new_layout) &&
+ rs->delta_disks >= 0;
+
+ return change;
+}
+
+/* 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 compat_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;
+
+/*
+ * Check for reshape constraints on raid set @rs:
+ *
+ * - reshape function non-existent
+ * - degraded set
+ * - ongoing recovery
+ * - ongoing reshape
+ *
+ * Returns 0 if none or -EPERM if given constraint
+ * and error message reference in @errmsg
+ */
+static int rs_check_reshape(struct raid_set *rs)
+{
+ struct mddev *mddev = &rs->md;
+
+ if (!mddev->pers || !mddev->pers->check_reshape)
+ rs->ti->error = "Reshape not supported";
+ else if (mddev->degraded)
+ rs->ti->error = "Can't reshape degraded raid set";
+ else if (rs_is_recovering(rs))
+ rs->ti->error = "Convert request on recovering raid set prohibited";
+ else if (rs_is_reshaping(rs))
+ rs->ti->error = "raid set already reshaping!";
+ else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
+ rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
+ else
+ return 0;
+
+ return -EPERM;
+}
+
+static int read_disk_sb(struct md_rdev *rdev, int size, bool force_reload)
+{
+ BUG_ON(!rdev->sb_page);
+
+ if (rdev->sb_loaded && !force_reload)
+ return 0;
+
+ rdev->sb_loaded = 0;
+
+ if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, true)) {
+ DMERR("Failed to read superblock of device at position %d",
+ rdev->raid_disk);
+ md_error(rdev->mddev, rdev);
+ set_bit(Faulty, &rdev->flags);
+ return -EIO;
+ }
+
+ 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);
+
+ /********************************************************************
+ * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
+ *
+ * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
+ */
+ 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);
+ sb->incompat_features = cpu_to_le32(0);
+
+ /* 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;
+
+ r = read_disk_sb(rdev, rdev->sb_size, false);
+ 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_SB_CHANGE_DEVS, &rdev->mddev->sb_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;
+
+ 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);
+
+ /*
+ * 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->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
+ */
+ struct raid_type *rt_cur = get_raid_type_by_ll(mddev->level, mddev->layout);
+ struct raid_type *rt_new = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
+
+ if (rs_takeover_requested(rs)) {
+ if (rt_cur && rt_new)
+ DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",
+ rt_cur->name, rt_new->name);
+ else
+ DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");
+ return -EINVAL;
+ } else if (rs_reshape_requested(rs)) {
+ DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");
+ if (mddev->layout != mddev->new_layout) {
+ if (rt_cur && rt_new)
+ DMERR(" current layout %s vs new layout %s",
+ rt_cur->name, rt_new->name);
+ else
+ DMERR(" current layout 0x%X vs new layout 0x%X",
+ le32_to_cpu(sb->layout), mddev->new_layout);
+ }
+ if (mddev->chunk_sectors != mddev->new_chunk_sectors)
+ DMERR(" current stripe sectors %u vs new stripe sectors %u",
+ mddev->chunk_sectors, mddev->new_chunk_sectors);
+ if (rs->delta_disks)
+ DMERR(" current %u disks vs new %u disks",
+ mddev->raid_disks, mddev->raid_disks + rs->delta_disks);
+ if (rs_is_raid10(rs)) {
+ DMERR(" Old layout: %s w/ %u copies",
+ raid10_md_layout_to_format(mddev->layout),
+ raid10_md_layout_to_copies(mddev->layout));
+ DMERR(" New layout: %s w/ %u copies",
+ raid10_md_layout_to_format(mddev->new_layout),
+ raid10_md_layout_to_copies(mddev->new_layout));
+ }
+ return -EINVAL;
+ }
+
+ DMINFO("Discovered old metadata format; upgrading to extended metadata format");
+ }
+
+ 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.
+ * 3) This is/are a new device(s) being added to an old
+ * raid set during takeover to a higher raid level
+ * to provide capacity for redundancy or during reshape
+ * to add capacity to grow the raid set.
+ */
+ d = 0;
+ rdev_for_each(r, mddev) {
+ if (test_bit(Journal, &rdev->flags))
+ continue;
+
+ 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 == rs->raid_disks) {
+ DMINFO("Superblocks created for new raid set");
+ set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
+ } else if (new_devs != rebuilds &&
+ new_devs != rs->delta_disks) {
+ 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 (!test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && rs_is_recovering(rs)) {
+ DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
+ (unsigned long long) mddev->recovery_cp);
+ return -EINVAL;
+ } else if (rs_is_reshaping(rs)) {
+ DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
+ (unsigned long long) mddev->reshape_position);
+ 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 (test_bit(Journal, &rdev->flags) ||
+ !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 (rs_is_raid10(rs) && __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 || rdev->raid_disk < 0)
+ 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) &&
+ 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 on @rs unless no metadevs or raid0 or journaled raid4/5/6 set. */
+ mddev->bitmap_info.offset = (rt_is_raid0(rs->raid_type) || rs->journal_dev.dev) ? 0 : to_sector(4096);
+ mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
+
+ if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
+ /*
+ * Retrieve rdev size stored in superblock to be prepared for shrink.
+ * Check extended superblock members are present otherwise the size
+ * will not be set!
+ */
+ if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190)
+ 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_is_reshaping(rs))
+ 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 md_rdev *rdev, *freshest;
+ struct mddev *mddev = &rs->md;
+
+ freshest = NULL;
+ rdev_for_each(rdev, mddev) {
+ if (test_bit(Journal, &rdev->flags))
+ continue;
+
+ if (!rdev->meta_bdev)
+ continue;
+
+ /* Set superblock offset/size for metadata device. */
+ rdev->sb_start = 0;
+ rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
+ if (rdev->sb_size < sizeof(struct dm_raid_superblock) || rdev->sb_size > PAGE_SIZE) {
+ DMERR("superblock size of a logical block is no longer valid");
+ return -EINVAL;
+ }
+
+ /*
+ * 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.
+ *
+ * With reshaping capability added, we must ensure that
+ * the "sync" directive is disallowed during the reshape.
+ */
+ if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
+ continue;
+
+ r = super_load(rdev, freshest);
+
+ switch (r) {
+ case 1:
+ freshest = rdev;
+ break;
+ case 0:
+ break;
+ default:
+ /* This is a failure to read the superblock from the metadata device. */
+ /*
+ * We have to keep any raid0 data/metadata device pairs or
+ * the MD raid0 personality will fail to start the array.
+ */
+ if (rs_is_raid0(rs))
+ continue;
+
+ /*
+ * We keep the dm_devs to be able to emit the device tuple
+ * properly on the table line in raid_status() (rather than
+ * mistakenly acting as if '- -' got passed into the constructor).
+ *
+ * The rdev has to stay on the same_set list to allow for
+ * the attempt to restore faulty devices on second resume.
+ */
+ rdev->raid_disk = rdev->saved_raid_disk = -1;
+ break;
+ }
+ }
+
+ if (!freshest)
+ return 0;
+
+ /*
+ * Validation of the freshest device provides the source of
+ * validation for the remaining devices.
+ */
+ rs->ti->error = "Unable to assemble array: Invalid superblocks";
+ if (super_validate(rs, freshest))
+ return -EINVAL;
+
+ if (validate_raid_redundancy(rs)) {
+ rs->ti->error = "Insufficient redundancy to activate array";
+ return -EINVAL;
+ }
+
+ rdev_for_each(rdev, mddev)
+ if (!test_bit(Journal, &rdev->flags) &&
+ rdev != freshest &&
+ super_validate(rs, rdev))
+ return -EINVAL;
+ return 0;
+}
+
+/*
+ * Adjust data_offset and new_data_offset on all disk members of @rs
+ * for out of place reshaping if requested by constructor
+ *
+ * We need free space at the beginning of each raid disk for forward
+ * and at the end for backward reshapes which userspace has to provide
+ * via remapping/reordering of space.
+ */
+static int rs_adjust_data_offsets(struct raid_set *rs)
+{
+ sector_t data_offset = 0, new_data_offset = 0;
+ struct md_rdev *rdev;
+
+ /* Constructor did not request data offset change */
+ if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
+ if (!rs_is_reshapable(rs))
+ goto out;
+
+ return 0;
+ }
+
+ /* HM FIXME: get In_Sync raid_dev? */
+ rdev = &rs->dev[0].rdev;
+
+ if (rs->delta_disks < 0) {
+ /*
+ * Removing disks (reshaping backwards):
+ *
+ * - before reshape: data is at offset 0 and free space
+ * is at end of each component LV
+ *
+ * - after reshape: data is at offset rs->data_offset != 0 on each component LV
+ */
+ data_offset = 0;
+ new_data_offset = rs->data_offset;
+
+ } else if (rs->delta_disks > 0) {
+ /*
+ * Adding disks (reshaping forwards):
+ *
+ * - before reshape: data is at offset rs->data_offset != 0 and
+ * free space is at begin of each component LV
+ *
+ * - after reshape: data is at offset 0 on each component LV
+ */
+ data_offset = rs->data_offset;
+ new_data_offset = 0;
+
+ } else {
+ /*
+ * User space passes in 0 for data offset after having removed reshape space
+ *
+ * - or - (data offset != 0)
+ *
+ * Changing RAID layout or chunk size -> toggle offsets
+ *
+ * - before reshape: data is at offset rs->data_offset 0 and
+ * free space is at end of each component LV
+ * -or-
+ * data is at offset rs->data_offset != 0 and
+ * free space is at begin of each component LV
+ *
+ * - after reshape: data is at offset 0 if it was at offset != 0
+ * or at offset != 0 if it was at offset 0
+ * on each component LV
+ *
+ */
+ data_offset = rs->data_offset ? rdev->data_offset : 0;
+ new_data_offset = data_offset ? 0 : rs->data_offset;
+ set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
+ }
+
+ /*
+ * Make sure we got a minimum amount of free sectors per device
+ */
+ if (rs->data_offset &&
+ bdev_nr_sectors(rdev->bdev) - rs->md.dev_sectors < MIN_FREE_RESHAPE_SPACE) {
+ rs->ti->error = data_offset ? "No space for forward reshape" :
+ "No space for backward reshape";
+ return -ENOSPC;
+ }
+out:
+ /*
+ * Raise recovery_cp in case data_offset != 0 to
+ * avoid false recovery positives in the constructor.
+ */
+ if (rs->md.recovery_cp < rs->md.dev_sectors)
+ rs->md.recovery_cp += rs->dev[0].rdev.data_offset;
+
+ /* Adjust data offsets on all rdevs but on any raid4/5/6 journal device */
+ rdev_for_each(rdev, &rs->md) {
+ if (!test_bit(Journal, &rdev->flags)) {
+ rdev->data_offset = data_offset;
+ rdev->new_data_offset = new_data_offset;
+ }
+ }
+
+ 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) {
+ if (!test_bit(Journal, &rdev->flags)) {
+ 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 (rs_is_raid0(rs)) {
+ /* 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 (rs_is_raid1(rs))
+ /* 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;
+}
+
+/* Prepare @rs for reshape */
+static int rs_prepare_reshape(struct raid_set *rs)
+{
+ bool reshape;
+ struct mddev *mddev = &rs->md;
+
+ if (rs_is_raid10(rs)) {
+ if (rs->raid_disks != mddev->raid_disks &&
+ __is_raid10_near(mddev->layout) &&
+ rs->raid10_copies &&
+ rs->raid10_copies != __raid10_near_copies(mddev->layout)) {
+ /*
+ * raid disk have to be multiple of data copies to allow this conversion,
+ *
+ * This is actually not a reshape it is a
+ * rebuild of any additional mirrors per group
+ */
+ if (rs->raid_disks % rs->raid10_copies) {
+ rs->ti->error = "Can't reshape raid10 mirror groups";
+ return -EINVAL;
+ }
+
+ /* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
+ __reorder_raid_disk_indexes(rs);
+ mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
+ rs->raid10_copies);
+ mddev->new_layout = mddev->layout;
+ reshape = false;
+ } else
+ reshape = true;
+
+ } else if (rs_is_raid456(rs))
+ reshape = true;
+
+ else if (rs_is_raid1(rs)) {
+ if (rs->delta_disks) {
+ /* Process raid1 via delta_disks */
+ mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
+ reshape = true;
+ } else {
+ /* Process raid1 without delta_disks */
+ mddev->raid_disks = rs->raid_disks;
+ reshape = false;
+ }
+ } else {
+ rs->ti->error = "Called with bogus raid type";
+ return -EINVAL;
+ }
+
+ if (reshape) {
+ set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
+ set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
+ } else if (mddev->raid_disks < rs->raid_disks)
+ /* Create new superblocks and bitmaps, if any new disks */
+ set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
+
+ return 0;
+}
+
+/* Get reshape sectors from data_offsets or raid set */
+static sector_t _get_reshape_sectors(struct raid_set *rs)
+{
+ struct md_rdev *rdev;
+ sector_t reshape_sectors = 0;
+
+ rdev_for_each(rdev, &rs->md)
+ if (!test_bit(Journal, &rdev->flags)) {
+ reshape_sectors = (rdev->data_offset > rdev->new_data_offset) ?
+ rdev->data_offset - rdev->new_data_offset :
+ rdev->new_data_offset - rdev->data_offset;
+ break;
+ }
+
+ return max(reshape_sectors, (sector_t) rs->data_offset);
+}
+
+/*
+ * Reshape:
+ * - change raid layout
+ * - change chunk size
+ * - add disks
+ * - remove disks
+ */
+static int rs_setup_reshape(struct raid_set *rs)
+{
+ int r = 0;
+ unsigned int cur_raid_devs, d;
+ sector_t reshape_sectors = _get_reshape_sectors(rs);
+ struct mddev *mddev = &rs->md;
+ struct md_rdev *rdev;
+
+ mddev->delta_disks = rs->delta_disks;
+ cur_raid_devs = mddev->raid_disks;
+
+ /* Ignore impossible layout change whilst adding/removing disks */
+ if (mddev->delta_disks &&
+ mddev->layout != mddev->new_layout) {
+ DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
+ mddev->new_layout = mddev->layout;
+ }
+
+ /*
+ * Adjust array size:
+ *
+ * - in case of adding disk(s), array size has
+ * to grow after the disk adding reshape,
+ * which'll hapen in the event handler;
+ * reshape will happen forward, so space has to
+ * be available at the beginning of each disk
+ *
+ * - in case of removing disk(s), array size
+ * has to shrink before starting the reshape,
+ * which'll happen here;
+ * reshape will happen backward, so space has to
+ * be available at the end of each disk
+ *
+ * - data_offset and new_data_offset are
+ * adjusted for aforementioned out of place
+ * reshaping based on userspace passing in
+ * the "data_offset <sectors>" key/value
+ * pair via the constructor
+ */
+
+ /* Add disk(s) */
+ if (rs->delta_disks > 0) {
+ /* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
+ for (d = cur_raid_devs; d < rs->raid_disks; d++) {
+ rdev = &rs->dev[d].rdev;
+ clear_bit(In_sync, &rdev->flags);
+
+ /*
+ * save_raid_disk needs to be -1, or recovery_offset will be set to 0
+ * by md, which'll store that erroneously in the superblock on reshape
+ */
+ rdev->saved_raid_disk = -1;
+ rdev->raid_disk = d;
+
+ rdev->sectors = mddev->dev_sectors;
+ rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
+ }
+
+ mddev->reshape_backwards = 0; /* adding disk(s) -> forward reshape */
+
+ /* Remove disk(s) */
+ } else if (rs->delta_disks < 0) {
+ r = rs_set_dev_and_array_sectors(rs, rs->ti->len, true);
+ mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
+
+ /* Change layout and/or chunk size */
+ } else {
+ /*
+ * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
+ *
+ * keeping number of disks and do layout change ->
+ *
+ * toggle reshape_backward depending on data_offset:
+ *
+ * - free space upfront -> reshape forward
+ *
+ * - free space at the end -> reshape backward
+ *
+ *
+ * This utilizes free reshape space avoiding the need
+ * for userspace to move (parts of) LV segments in
+ * case of layout/chunksize change (for disk
+ * adding/removing reshape space has to be at
+ * the proper address (see above with delta_disks):
+ *
+ * add disk(s) -> begin
+ * remove disk(s)-> end
+ */
+ mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
+ }
+
+ /*
+ * Adjust device size for forward reshape
+ * because md_finish_reshape() reduces it.
+ */
+ if (!mddev->reshape_backwards)
+ rdev_for_each(rdev, &rs->md)
+ if (!test_bit(Journal, &rdev->flags))
+ rdev->sectors += reshape_sectors;
+
+ return r;
+}
+
+/*
+ * If the md resync thread has updated superblock with max reshape position
+ * at the end of a reshape but not (yet) reset the layout configuration
+ * changes -> reset the latter.
+ */
+static void rs_reset_inconclusive_reshape(struct raid_set *rs)
+{
+ if (!rs_is_reshaping(rs) && rs_is_layout_change(rs, true)) {
+ rs_set_cur(rs);
+ rs->md.delta_disks = 0;
+ rs->md.reshape_backwards = 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;
+
+ /*
+ * XXX: RAID level 4,5,6 require zeroing for safety.
+ */
+ raid456 = rs_is_raid456(rs);
+
+ for (i = 0; i < rs->raid_disks; i++) {
+ if (!rs->dev[i].rdev.bdev ||
+ !bdev_max_discard_sectors(rs->dev[i].rdev.bdev))
+ return;
+
+ if (raid456) {
+ 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;
+ }
+ }
+ }
+
+ 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 int argc, char **argv)
+{
+ int r;
+ bool resize = false;
+ struct raid_type *rt;
+ unsigned int num_raid_params, num_raid_devs;
+ sector_t sb_array_sectors, rdev_sectors, reshape_sectors;
+ struct raid_set *rs = NULL;
+ const char *arg;
+ struct rs_layout rs_layout;
+ 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" }
+ };
+
+ 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;
+
+ /*
+ * Calculate ctr requested array and device sizes to allow
+ * for superblock analysis needing device sizes defined.
+ *
+ * Any existing superblock will overwrite the array and device sizes
+ */
+ r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);
+ if (r)
+ goto bad;
+
+ /* Memorize just calculated, potentially larger sizes to grow the raid set in preresume */
+ rs->array_sectors = rs->md.array_sectors;
+ rs->dev_sectors = rs->md.dev_sectors;
+
+ /*
+ * Backup any new raid set level, layout, ...
+ * requested to be able to compare to superblock
+ * members for conversion decisions.
+ */
+ rs_config_backup(rs, &rs_layout);
+
+ r = analyse_superblocks(ti, rs);
+ if (r)
+ goto bad;
+
+ /* All in-core metadata now as of current superblocks after calling analyse_superblocks() */
+ sb_array_sectors = rs->md.array_sectors;
+ rdev_sectors = __rdev_sectors(rs);
+ if (!rdev_sectors) {
+ ti->error = "Invalid rdev size";
+ r = -EINVAL;
+ goto bad;
+ }
+
+
+ reshape_sectors = _get_reshape_sectors(rs);
+ if (rs->dev_sectors != rdev_sectors) {
+ resize = (rs->dev_sectors != rdev_sectors - reshape_sectors);
+ if (rs->dev_sectors > rdev_sectors - reshape_sectors)
+ set_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
+ }
+
+ INIT_WORK(&rs->md.event_work, do_table_event);
+ ti->private = rs;
+ ti->num_flush_bios = 1;
+ ti->needs_bio_set_dev = true;
+
+ /* Restore any requested new layout for conversion decision */
+ rs_config_restore(rs, &rs_layout);
+
+ /*
+ * Now that we have any superblock metadata available,
+ * check for new, recovering, reshaping, to be taken over,
+ * to be reshaped or an existing, unchanged raid set to
+ * run in sequence.
+ */
+ if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
+ /* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
+ if (rs_is_raid6(rs) &&
+ test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
+ ti->error = "'nosync' not allowed for new raid6 set";
+ r = -EINVAL;
+ goto bad;
+ }
+ rs_setup_recovery(rs, 0);
+ set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
+ rs_set_new(rs);
+ } else if (rs_is_recovering(rs)) {
+ /* A recovering raid set may be resized */
+ goto size_check;
+ } else if (rs_is_reshaping(rs)) {
+ /* Have to reject size change request during reshape */
+ if (resize) {
+ ti->error = "Can't resize a reshaping raid set";
+ r = -EPERM;
+ goto bad;
+ }
+ /* skip setup rs */
+ } else if (rs_takeover_requested(rs)) {
+ if (rs_is_reshaping(rs)) {
+ ti->error = "Can't takeover a reshaping raid set";
+ r = -EPERM;
+ goto bad;
+ }
+
+ /* We can't takeover a journaled raid4/5/6 */
+ if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
+ ti->error = "Can't takeover a journaled raid4/5/6 set";
+ r = -EPERM;
+ goto bad;
+ }
+
+ /*
+ * If a takeover is needed, userspace sets any additional
+ * devices to rebuild and we can check for a valid request here.
+ *
+ * If acceptible, set the level to the new requested
+ * one, prohibit requesting recovery, allow the raid
+ * set to run and store superblocks during resume.
+ */
+ r = rs_check_takeover(rs);
+ if (r)
+ goto bad;
+
+ r = rs_setup_takeover(rs);
+ if (r)
+ goto bad;
+
+ set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
+ /* Takeover ain't recovery, so disable recovery */
+ rs_setup_recovery(rs, MaxSector);
+ rs_set_new(rs);
+ } else if (rs_reshape_requested(rs)) {
+ /* Only request grow on raid set size extensions, not on reshapes. */
+ clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
+
+ /*
+ * No need to check for 'ongoing' takeover here, because takeover
+ * is an instant operation as oposed to an ongoing reshape.
+ */
+
+ /* We can't reshape a journaled raid4/5/6 */
+ if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
+ ti->error = "Can't reshape a journaled raid4/5/6 set";
+ r = -EPERM;
+ goto bad;
+ }
+
+ /* Out-of-place space has to be available to allow for a reshape unless raid1! */
+ if (reshape_sectors || rs_is_raid1(rs)) {
+ /*
+ * We can only prepare for a reshape here, because the
+ * raid set needs to run to provide the repective reshape
+ * check functions via its MD personality instance.
+ *
+ * So do the reshape check after md_run() succeeded.
+ */
+ r = rs_prepare_reshape(rs);
+ if (r)
+ goto bad;
+
+ /* Reshaping ain't recovery, so disable recovery */
+ rs_setup_recovery(rs, MaxSector);
+ }
+ rs_set_cur(rs);
+ } else {
+size_check:
+ /* May not set recovery when a device rebuild is requested */
+ if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
+ clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
+ set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
+ rs_setup_recovery(rs, MaxSector);
+ } else if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
+ /*
+ * Set raid set to current size, i.e. size as of
+ * superblocks to grow to larger size in preresume.
+ */
+ r = rs_set_dev_and_array_sectors(rs, sb_array_sectors, false);
+ if (r)
+ goto bad;
+
+ rs_setup_recovery(rs, rs->md.recovery_cp < rs->md.dev_sectors ? rs->md.recovery_cp : rs->md.dev_sectors);
+ } else {
+ /* This is no size change or it is shrinking, update size and record in superblocks */
+ r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);
+ if (r)
+ goto bad;
+
+ if (sb_array_sectors > rs->array_sectors)
+ set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
+ }
+ rs_set_cur(rs);
+ }
+
+ /* If constructor requested it, change data and new_data offsets */
+ r = rs_adjust_data_offsets(rs);
+ if (r)
+ goto bad;
+
+ /* Catch any inconclusive reshape superblock content. */
+ rs_reset_inconclusive_reshape(rs);
+
+ /* Start raid set read-only and assumed clean to change in raid_resume() */
+ rs->md.ro = 1;
+ rs->md.in_sync = 1;
+
+ /* Keep array frozen until resume. */
+ 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 */
+ if (r) {
+ ti->error = "Failed to run raid array";
+ mddev_unlock(&rs->md);
+ goto bad;
+ }
+
+ r = md_start(&rs->md);
+ if (r) {
+ ti->error = "Failed to start raid array";
+ goto bad_unlock;
+ }
+
+ /* If raid4/5/6 journal mode explicitly requested (only possible with journal dev) -> set it */
+ if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
+ r = r5c_journal_mode_set(&rs->md, rs->journal_dev.mode);
+ if (r) {
+ ti->error = "Failed to set raid4/5/6 journal mode";
+ goto bad_unlock;
+ }
+ }
+
+ mddev_suspend(&rs->md);
+ set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags);
+
+ /* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
+ if (rs_is_raid456(rs)) {
+ r = rs_set_raid456_stripe_cache(rs);
+ if (r)
+ goto bad_unlock;
+ }
+
+ /* Now do an early reshape check */
+ if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
+ r = rs_check_reshape(rs);
+ if (r)
+ goto bad_unlock;
+
+ /* Restore new, ctr requested layout to perform check */
+ rs_config_restore(rs, &rs_layout);
+
+ if (rs->md.pers->start_reshape) {
+ r = rs->md.pers->check_reshape(&rs->md);
+ if (r) {
+ ti->error = "Reshape check failed";
+ goto bad_unlock;
+ }
+ }
+ }
+
+ /* Disable/enable discard support on raid set. */
+ configure_discard_support(rs);
+
+ mddev_unlock(&rs->md);
+ return 0;
+
+bad_unlock:
+ md_stop(&rs->md);
+ mddev_unlock(&rs->md);
+bad:
+ raid_set_free(rs);
+
+ return r;
+}
+
+static void raid_dtr(struct dm_target *ti)
+{
+ struct raid_set *rs = ti->private;
+
+ mddev_lock_nointr(&rs->md);
+ md_stop(&rs->md);
+ mddev_unlock(&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;
+
+ /*
+ * If we're reshaping to add disk(s)), ti->len and
+ * mddev->array_sectors will differ during the process
+ * (ti->len > mddev->array_sectors), so we have to requeue
+ * bios with addresses > mddev->array_sectors here or
+ * there will occur accesses past EOD of the component
+ * data images thus erroring the raid set.
+ */
+ if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
+ return DM_MAPIO_REQUEUE;
+
+ md_handle_request(mddev, bio);
+
+ return DM_MAPIO_SUBMITTED;
+}
+
+/* Return sync state string for @state */
+enum sync_state { st_frozen, st_reshape, st_resync, st_check, st_repair, st_recover, st_idle };
+static const char *sync_str(enum sync_state state)
+{
+ /* Has to be in above sync_state order! */
+ static const char *sync_strs[] = {
+ "frozen",
+ "reshape",
+ "resync",
+ "check",
+ "repair",
+ "recover",
+ "idle"
+ };
+
+ return __within_range(state, 0, ARRAY_SIZE(sync_strs) - 1) ? sync_strs[state] : "undef";
+};
+
+/* Return enum sync_state for @mddev derived from @recovery flags */
+static enum sync_state decipher_sync_action(struct mddev *mddev, unsigned long recovery)
+{
+ if (test_bit(MD_RECOVERY_FROZEN, &recovery))
+ return st_frozen;
+
+ /* The MD sync thread can be done with io or be interrupted but still be running */
+ if (!test_bit(MD_RECOVERY_DONE, &recovery) &&
+ (test_bit(MD_RECOVERY_RUNNING, &recovery) ||
+ (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery)))) {
+ if (test_bit(MD_RECOVERY_RESHAPE, &recovery))
+ return st_reshape;
+
+ if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
+ if (!test_bit(MD_RECOVERY_REQUESTED, &recovery))
+ return st_resync;
+ if (test_bit(MD_RECOVERY_CHECK, &recovery))
+ return st_check;
+ return st_repair;
+ }
+
+ if (test_bit(MD_RECOVERY_RECOVER, &recovery))
+ return st_recover;
+
+ if (mddev->reshape_position != MaxSector)
+ return st_reshape;
+ }
+
+ return st_idle;
+}
+
+/*
+ * Return status string for @rdev
+ *
+ * Status characters:
+ *
+ * 'D' = Dead/Failed raid set component or raid4/5/6 journal device
+ * 'a' = Alive but not in-sync raid set component _or_ alive raid4/5/6 'write_back' journal device
+ * 'A' = Alive and in-sync raid set component _or_ alive raid4/5/6 'write_through' journal device
+ * '-' = Non-existing device (i.e. uspace passed '- -' into the ctr)
+ */
+static const char *__raid_dev_status(struct raid_set *rs, struct md_rdev *rdev)
+{
+ if (!rdev->bdev)
+ return "-";
+ else if (test_bit(Faulty, &rdev->flags))
+ return "D";
+ else if (test_bit(Journal, &rdev->flags))
+ return (rs->journal_dev.mode == R5C_JOURNAL_MODE_WRITE_THROUGH) ? "A" : "a";
+ else if (test_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags) ||
+ (!test_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags) &&
+ !test_bit(In_sync, &rdev->flags)))
+ return "a";
+ else
+ return "A";
+}
+
+/* Helper to return resync/reshape progress for @rs and runtime flags for raid set in sync / resynching */
+static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery,
+ enum sync_state state, sector_t resync_max_sectors)
+{
+ sector_t r;
+ struct mddev *mddev = &rs->md;
+
+ clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
+ clear_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
+
+ if (rs_is_raid0(rs)) {
+ r = resync_max_sectors;
+ set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
+
+ } else {
+ if (state == st_idle && !test_bit(MD_RECOVERY_INTR, &recovery))
+ r = mddev->recovery_cp;
+ else
+ r = mddev->curr_resync_completed;
+
+ if (state == st_idle && r >= resync_max_sectors) {
+ /*
+ * Sync complete.
+ */
+ /* In case we have finished recovering, the array is in sync. */
+ if (test_bit(MD_RECOVERY_RECOVER, &recovery))
+ set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
+
+ } else if (state == st_recover)
+ /*
+ * In case we are recovering, the array is not in sync
+ * and health chars should show the recovering legs.
+ *
+ * Already retrieved recovery offset from curr_resync_completed above.
+ */
+ ;
+
+ else if (state == st_resync || state == st_reshape)
+ /*
+ * If "resync/reshape" is occurring, the raid set
+ * is or may be out of sync hence the health
+ * characters shall be 'a'.
+ */
+ set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
+
+ else if (state == st_check || state == st_repair)
+ /*
+ * If "check" or "repair" is occurring, the raid set has
+ * undergone an initial sync and the health characters
+ * should not be 'a' anymore.
+ */
+ set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
+
+ else if (test_bit(MD_RECOVERY_NEEDED, &recovery))
+ /*
+ * We are idle and recovery is needed, prevent 'A' chars race
+ * caused by components still set to in-sync by constructor.
+ */
+ set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
+
+ else {
+ /*
+ * We are idle and 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.
+ */
+ struct md_rdev *rdev;
+
+ set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
+ rdev_for_each(rdev, mddev)
+ if (!test_bit(Journal, &rdev->flags) &&
+ !test_bit(In_sync, &rdev->flags)) {
+ clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
+ break;
+ }
+ }
+ }
+
+ return min(r, resync_max_sectors);
+}
+
+/* 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 = rs_is_raid456(rs) ? mddev->private : NULL;
+ int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
+ unsigned long recovery;
+ unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
+ unsigned int sz = 0;
+ unsigned int rebuild_writemostly_count = 0;
+ sector_t progress, resync_max_sectors, resync_mismatches;
+ enum sync_state state;
+ struct raid_type *rt;
+
+ 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->name, 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;
+ recovery = rs->md.recovery;
+ state = decipher_sync_action(mddev, recovery);
+ progress = rs_get_progress(rs, recovery, state, resync_max_sectors);
+ resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
+ atomic64_read(&mddev->resync_mismatches) : 0;
+
+ /* HM FIXME: do we want another state char for raid0? It shows 'D'/'A'/'-' now */
+ for (i = 0; i < rs->raid_disks; i++)
+ DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
+
+ /*
+ * 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/admin-guide/device-mapper/dm-raid.rst for
+ * information on each of these states.
+ */
+ DMEMIT(" %s", sync_str(state));
+
+ /*
+ * 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);
+
+ /*
+ * v1.10.0+:
+ */
+ DMEMIT(" %s", test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags) ?
+ __raid_dev_status(rs, &rs->journal_dev.rdev) : "-");
+ break;
+
+ case STATUSTYPE_TABLE:
+ /* Report the table line string you would use to construct this raid set */
+
+ /*
+ * Count any rebuild or writemostly argument pairs and subtract the
+ * hweight count being added below of any rebuild and writemostly ctr flags.
+ */
+ for (i = 0; i < rs->raid_disks; i++) {
+ rebuild_writemostly_count += (test_bit(i, (void *) rs->rebuild_disks) ? 2 : 0) +
+ (test_bit(WriteMostly, &rs->dev[i].rdev.flags) ? 2 : 0);
+ }
+ rebuild_writemostly_count -= (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) ? 2 : 0) +
+ (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags) ? 2 : 0);
+ /* Calculate raid parameter count based on ^ rebuild/writemostly argument counts and ctr flags set. */
+ raid_param_cnt += rebuild_writemostly_count +
+ hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
+ hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
+ /* Emit table line */
+ /* This has to be in the documented order for userspace! */
+ DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
+ 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_NOSYNC, &rs->ctr_flags))
+ DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
+ if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags))
+ for (i = 0; i < rs->raid_disks; i++)
+ if (test_bit(i, (void *) rs->rebuild_disks))
+ DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD), i);
+ 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_MIN_RECOVERY_RATE, &rs->ctr_flags))
+ DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
+ mddev->sync_speed_min);
+ 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_WRITE_MOSTLY, &rs->ctr_flags))
+ for (i = 0; i < rs->raid_disks; i++)
+ if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
+ DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
+ rs->dev[i].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_STRIPE_CACHE, &rs->ctr_flags))
+ DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
+ max_nr_stripes);
+ 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_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_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_DELTA_DISKS, &rs->ctr_flags))
+ DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
+ max(rs->delta_disks, mddev->delta_disks));
+ 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_JOURNAL_DEV, &rs->ctr_flags))
+ DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV),
+ __get_dev_name(rs->journal_dev.dev));
+ if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags))
+ DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE),
+ md_journal_mode_to_dm_raid(rs->journal_dev.mode));
+ DMEMIT(" %d", rs->raid_disks);
+ for (i = 0; i < rs->raid_disks; i++)
+ DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
+ __get_dev_name(rs->dev[i].data_dev));
+ break;
+
+ case STATUSTYPE_IMA:
+ rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
+ if (!rt)
+ return;
+
+ DMEMIT_TARGET_NAME_VERSION(ti->type);
+ DMEMIT(",raid_type=%s,raid_disks=%d", rt->name, mddev->raid_disks);
+
+ /* Access most recent mddev properties for status output */
+ smp_rmb();
+ recovery = rs->md.recovery;
+ state = decipher_sync_action(mddev, recovery);
+ DMEMIT(",raid_state=%s", sync_str(state));
+
+ for (i = 0; i < rs->raid_disks; i++) {
+ DMEMIT(",raid_device_%d_status=", i);
+ DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
+ }
+
+ if (rt_is_raid456(rt)) {
+ DMEMIT(",journal_dev_mode=");
+ switch (rs->journal_dev.mode) {
+ case R5C_JOURNAL_MODE_WRITE_THROUGH:
+ DMEMIT("%s",
+ _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_THROUGH].param);
+ break;
+ case R5C_JOURNAL_MODE_WRITE_BACK:
+ DMEMIT("%s",
+ _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_BACK].param);
+ break;
+ default:
+ DMEMIT("invalid");
+ break;
+ }
+ }
+ DMEMIT(";");
+ break;
+ }
+}
+
+static int raid_message(struct dm_target *ti, unsigned int argc, char **argv,
+ char *result, unsigned int maxlen)
+{
+ struct raid_set *rs = ti->private;
+ struct mddev *mddev = &rs->md;
+
+ 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_unregister_thread(&mddev->sync_thread);
+ md_reap_sync_thread(mddev);
+ }
+ } else if (decipher_sync_action(mddev, mddev->recovery) != st_idle)
+ 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);
+ set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
+ set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
+ } else if (!strcasecmp(argv[0], "repair")) {
+ set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
+ set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
+ } else
+ return -EINVAL;
+ }
+ 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 int i;
+ int r = 0;
+
+ for (i = 0; !r && i < rs->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 int chunk_size_bytes = to_bytes(rs->md.chunk_sectors);
+
+ blk_limits_io_min(limits, chunk_size_bytes);
+ blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs));
+}
+
+static void raid_postsuspend(struct dm_target *ti)
+{
+ struct raid_set *rs = ti->private;
+
+ if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
+ /* Writes have to be stopped before suspending to avoid deadlocks. */
+ if (!test_bit(MD_RECOVERY_FROZEN, &rs->md.recovery))
+ md_stop_writes(&rs->md);
+
+ mddev_lock_nointr(&rs->md);
+ mddev_suspend(&rs->md);
+ mddev_unlock(&rs->md);
+ }
+}
+
+static void attempt_restore_of_faulty_devices(struct raid_set *rs)
+{
+ int i;
+ uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];
+ unsigned long flags;
+ bool cleared = false;
+ struct dm_raid_superblock *sb;
+ struct mddev *mddev = &rs->md;
+ struct md_rdev *r;
+
+ /* RAID personalities have to provide hot add/remove methods or we need to bail out. */
+ if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)
+ return;
+
+ memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));
+
+ for (i = 0; i < rs->raid_disks; i++) {
+ r = &rs->dev[i].rdev;
+ /* HM FIXME: enhance journal device recovery processing */
+ if (test_bit(Journal, &r->flags))
+ continue;
+
+ if (test_bit(Faulty, &r->flags) &&
+ r->meta_bdev && !read_disk_sb(r, r->sb_size, true)) {
+ 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.
+ */
+ flags = r->flags;
+ clear_bit(In_sync, &r->flags); /* Mandatory for hot remove. */
+ if (r->raid_disk >= 0) {
+ if (mddev->pers->hot_remove_disk(mddev, r)) {
+ /* Failed to revive this device, try next */
+ r->flags = flags;
+ continue;
+ }
+ } else
+ r->raid_disk = r->saved_raid_disk = i;
+
+ clear_bit(Faulty, &r->flags);
+ clear_bit(WriteErrorSeen, &r->flags);
+
+ if (mddev->pers->hot_add_disk(mddev, r)) {
+ /* Failed to revive this device, try next */
+ r->raid_disk = r->saved_raid_disk = -1;
+ r->flags = flags;
+ } else {
+ clear_bit(In_sync, &r->flags);
+ r->recovery_offset = 0;
+ set_bit(i, (void *) cleared_failed_devices);
+ cleared = true;
+ }
+ }
+ }
+
+ /* If any failed devices could be cleared, update all sbs failed_devices bits */
+ if (cleared) {
+ uint64_t failed_devices[DISKS_ARRAY_ELEMS];
+
+ rdev_for_each(r, &rs->md) {
+ if (test_bit(Journal, &r->flags))
+ continue;
+
+ sb = page_address(r->sb_page);
+ sb_retrieve_failed_devices(sb, failed_devices);
+
+ for (i = 0; i < DISKS_ARRAY_ELEMS; i++)
+ failed_devices[i] &= ~cleared_failed_devices[i];
+
+ sb_update_failed_devices(sb, 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 = md_bitmap_load(&rs->md);
+ if (r)
+ DMERR("Failed to load bitmap");
+ }
+
+ return r;
+}
+
+/* Enforce updating all superblocks */
+static void rs_update_sbs(struct raid_set *rs)
+{
+ struct mddev *mddev = &rs->md;
+ int ro = mddev->ro;
+
+ set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
+ mddev->ro = 0;
+ md_update_sb(mddev, 1);
+ mddev->ro = ro;
+}
+
+/*
+ * Reshape changes raid algorithm of @rs to new one within personality
+ * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
+ * disks from a raid set thus growing/shrinking it or resizes the set
+ *
+ * Call mddev_lock_nointr() before!
+ */
+static int rs_start_reshape(struct raid_set *rs)
+{
+ int r;
+ struct mddev *mddev = &rs->md;
+ struct md_personality *pers = mddev->pers;
+
+ /* Don't allow the sync thread to work until the table gets reloaded. */
+ set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
+
+ r = rs_setup_reshape(rs);
+ if (r)
+ return r;
+
+ /*
+ * Check any reshape constraints enforced by the personalility
+ *
+ * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
+ */
+ r = pers->check_reshape(mddev);
+ if (r) {
+ rs->ti->error = "pers->check_reshape() failed";
+ return r;
+ }
+
+ /*
+ * Personality may not provide start reshape method in which
+ * case check_reshape above has already covered everything
+ */
+ if (pers->start_reshape) {
+ r = pers->start_reshape(mddev);
+ if (r) {
+ rs->ti->error = "pers->start_reshape() failed";
+ return r;
+ }
+ }
+
+ /*
+ * Now reshape got set up, update superblocks to
+ * reflect the fact so that a table reload will
+ * access proper superblock content in the ctr.
+ */
+ rs_update_sbs(rs);
+
+ return 0;
+}
+
+static int raid_preresume(struct dm_target *ti)
+{
+ int r;
+ 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 new devices got added (thus zeroed
+ * out by userspace) or __load_dirty_region_bitmap
+ * will overwrite them in core with old data or fail.
+ */
+ if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
+ rs_update_sbs(rs);
+
+ /* Load the bitmap from disk unless raid0 */
+ r = __load_dirty_region_bitmap(rs);
+ if (r)
+ return r;
+
+ /* We are extending the raid set size, adjust mddev/md_rdev sizes and set capacity. */
+ if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
+ mddev->array_sectors = rs->array_sectors;
+ mddev->dev_sectors = rs->dev_sectors;
+ rs_set_rdev_sectors(rs);
+ rs_set_capacity(rs);
+ }
+
+ /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) or grown device size */
+ if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
+ (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags) ||
+ (rs->requested_bitmap_chunk_sectors &&
+ mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)))) {
+ int chunksize = to_bytes(rs->requested_bitmap_chunk_sectors) ?: mddev->bitmap_info.chunksize;
+
+ r = md_bitmap_resize(mddev->bitmap, mddev->dev_sectors, chunksize, 0);
+ if (r)
+ DMERR("Failed to resize bitmap");
+ }
+
+ /* Check for any resize/reshape on @rs and adjust/initiate */
+ /* Be prepared for mddev_resume() in raid_resume() */
+ set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
+ if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
+ set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
+ mddev->resync_min = mddev->recovery_cp;
+ if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags))
+ mddev->resync_max_sectors = mddev->dev_sectors;
+ }
+
+ /* Check for any reshape request unless new raid set */
+ if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
+ /* Initiate a reshape. */
+ rs_set_rdev_sectors(rs);
+ mddev_lock_nointr(mddev);
+ r = rs_start_reshape(rs);
+ mddev_unlock(mddev);
+ if (r)
+ DMWARN("Failed to check/start reshape, continuing without change");
+ r = 0;
+ }
+
+ return r;
+}
+
+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);
+ }
+
+ if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
+ /* Only reduce raid set size before running a disk removing reshape. */
+ if (mddev->delta_disks < 0)
+ rs_set_capacity(rs);
+
+ mddev_lock_nointr(mddev);
+ clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
+ mddev->ro = 0;
+ mddev->in_sync = 0;
+ mddev_resume(mddev);
+ mddev_unlock(mddev);
+ }
+}
+
+static struct target_type raid_target = {
+ .name = "raid",
+ .version = {1, 15, 1},
+ .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,
+ .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");