| /* |
| * Copyright (C) 2010-2011 Neil Brown |
| * Copyright (C) 2010-2011 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 "bitmap.h" |
| |
| #include <linux/device-mapper.h> |
| |
| #define DM_MSG_PREFIX "raid" |
| |
| /* |
| * 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; |
| }; |
| |
| /* |
| * Flags for rs->print_flags field. |
| */ |
| #define DMPF_SYNC 0x1 |
| #define DMPF_NOSYNC 0x2 |
| #define DMPF_REBUILD 0x4 |
| #define DMPF_DAEMON_SLEEP 0x8 |
| #define DMPF_MIN_RECOVERY_RATE 0x10 |
| #define DMPF_MAX_RECOVERY_RATE 0x20 |
| #define DMPF_MAX_WRITE_BEHIND 0x40 |
| #define DMPF_STRIPE_CACHE 0x80 |
| #define DMPF_REGION_SIZE 0X100 |
| struct raid_set { |
| struct dm_target *ti; |
| |
| uint32_t bitmap_loaded; |
| uint32_t print_flags; |
| |
| struct mddev md; |
| struct raid_type *raid_type; |
| struct dm_target_callbacks callbacks; |
| |
| struct raid_dev dev[0]; |
| }; |
| |
| /* Supported raid types and properties. */ |
| static struct raid_type { |
| const char *name; /* RAID algorithm. */ |
| const char *descr; /* Descriptor text for logging. */ |
| const unsigned parity_devs; /* # of parity devices. */ |
| const unsigned minimal_devs; /* minimal # of devices in set. */ |
| const unsigned level; /* RAID level. */ |
| const unsigned algorithm; /* RAID algorithm. */ |
| } raid_types[] = { |
| {"raid1", "RAID1 (mirroring)", 0, 2, 1, 0 /* NONE */}, |
| {"raid4", "RAID4 (dedicated parity disk)", 1, 2, 5, ALGORITHM_PARITY_0}, |
| {"raid5_la", "RAID5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC}, |
| {"raid5_ra", "RAID5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC}, |
| {"raid5_ls", "RAID5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC}, |
| {"raid5_rs", "RAID5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC}, |
| {"raid6_zr", "RAID6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART}, |
| {"raid6_nr", "RAID6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART}, |
| {"raid6_nc", "RAID6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE} |
| }; |
| |
| static struct raid_type *get_raid_type(char *name) |
| { |
| int i; |
| |
| for (i = 0; i < ARRAY_SIZE(raid_types); i++) |
| if (!strcmp(raid_types[i].name, name)) |
| return &raid_types[i]; |
| |
| return NULL; |
| } |
| |
| static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *raid_type, unsigned raid_devs) |
| { |
| unsigned i; |
| struct raid_set *rs; |
| sector_t sectors_per_dev; |
| |
| if (raid_devs <= raid_type->parity_devs) { |
| ti->error = "Insufficient number of devices"; |
| return ERR_PTR(-EINVAL); |
| } |
| |
| sectors_per_dev = ti->len; |
| if ((raid_type->level > 1) && |
| sector_div(sectors_per_dev, (raid_devs - raid_type->parity_devs))) { |
| ti->error = "Target length not divisible by number of data devices"; |
| return ERR_PTR(-EINVAL); |
| } |
| |
| rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL); |
| if (!rs) { |
| ti->error = "Cannot allocate raid context"; |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| mddev_init(&rs->md); |
| |
| rs->ti = ti; |
| rs->raid_type = raid_type; |
| rs->md.raid_disks = raid_devs; |
| rs->md.level = raid_type->level; |
| rs->md.new_level = rs->md.level; |
| rs->md.dev_sectors = sectors_per_dev; |
| rs->md.layout = raid_type->algorithm; |
| rs->md.new_layout = rs->md.layout; |
| rs->md.delta_disks = 0; |
| rs->md.recovery_cp = 0; |
| |
| for (i = 0; i < raid_devs; i++) |
| md_rdev_init(&rs->dev[i].rdev); |
| |
| /* |
| * Remaining items to be initialized by further RAID params: |
| * rs->md.persistent |
| * rs->md.external |
| * rs->md.chunk_sectors |
| * rs->md.new_chunk_sectors |
| */ |
| |
| return rs; |
| } |
| |
| static void context_free(struct raid_set *rs) |
| { |
| int i; |
| |
| for (i = 0; i < rs->md.raid_disks; i++) { |
| if (rs->dev[i].meta_dev) |
| dm_put_device(rs->ti, rs->dev[i].meta_dev); |
| md_rdev_clear(&rs->dev[i].rdev); |
| if (rs->dev[i].data_dev) |
| dm_put_device(rs->ti, rs->dev[i].data_dev); |
| } |
| |
| kfree(rs); |
| } |
| |
| /* |
| * For every device we have two words |
| * <meta_dev>: meta device name or '-' if missing |
| * <data_dev>: data device name or '-' if missing |
| * |
| * The following are permitted: |
| * - - |
| * - <data_dev> |
| * <meta_dev> <data_dev> |
| * |
| * The following is not allowed: |
| * <meta_dev> - |
| * |
| * This code parses those words. If there is a failure, |
| * the caller must use context_free to unwind the operations. |
| */ |
| static int dev_parms(struct raid_set *rs, char **argv) |
| { |
| int i; |
| int rebuild = 0; |
| int metadata_available = 0; |
| int ret = 0; |
| |
| for (i = 0; i < rs->md.raid_disks; i++, argv += 2) { |
| rs->dev[i].rdev.raid_disk = i; |
| |
| rs->dev[i].meta_dev = NULL; |
| rs->dev[i].data_dev = NULL; |
| |
| /* |
| * There are no offsets, since there is a separate device |
| * for data and metadata. |
| */ |
| rs->dev[i].rdev.data_offset = 0; |
| rs->dev[i].rdev.mddev = &rs->md; |
| |
| if (strcmp(argv[0], "-")) { |
| ret = dm_get_device(rs->ti, argv[0], |
| dm_table_get_mode(rs->ti->table), |
| &rs->dev[i].meta_dev); |
| rs->ti->error = "RAID metadata device lookup failure"; |
| if (ret) |
| return ret; |
| |
| rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL); |
| if (!rs->dev[i].rdev.sb_page) |
| return -ENOMEM; |
| } |
| |
| if (!strcmp(argv[1], "-")) { |
| 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; |
| } |
| |
| rs->ti->error = "No data device supplied with metadata device"; |
| if (rs->dev[i].meta_dev) |
| return -EINVAL; |
| |
| continue; |
| } |
| |
| ret = dm_get_device(rs->ti, argv[1], |
| dm_table_get_mode(rs->ti->table), |
| &rs->dev[i].data_dev); |
| if (ret) { |
| rs->ti->error = "RAID device lookup failure"; |
| return ret; |
| } |
| |
| 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(&rs->dev[i].rdev.same_set, &rs->md.disks); |
| if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) |
| rebuild++; |
| } |
| |
| if (metadata_available) { |
| rs->md.external = 0; |
| rs->md.persistent = 1; |
| rs->md.major_version = 2; |
| } else if (rebuild && !rs->md.recovery_cp) { |
| /* |
| * Without metadata, we will not be able to tell if the array |
| * is in-sync or not - we must assume it is not. Therefore, |
| * it is impossible to rebuild a drive. |
| * |
| * Even if there is metadata, the on-disk information may |
| * indicate that the array is not in-sync and it will then |
| * fail at that time. |
| * |
| * User could specify 'nosync' option if desperate. |
| */ |
| DMERR("Unable to rebuild drive while array is not in-sync"); |
| rs->ti->error = "RAID device lookup failure"; |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * validate_region_size |
| * @rs |
| * @region_size: region size in sectors. If 0, pick a size (4MiB default). |
| * |
| * Set rs->md.bitmap_info.chunksize (which really refers to 'region size'). |
| * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap. |
| * |
| * Returns: 0 on success, -EINVAL on failure. |
| */ |
| static int validate_region_size(struct raid_set *rs, unsigned long region_size) |
| { |
| unsigned long min_region_size = rs->ti->len / (1 << 21); |
| |
| if (!region_size) { |
| /* |
| * Choose a reasonable default. All figures in sectors. |
| */ |
| if (min_region_size > (1 << 13)) { |
| DMINFO("Choosing default region size of %lu sectors", |
| region_size); |
| region_size = min_region_size; |
| } else { |
| DMINFO("Choosing default region size of 4MiB"); |
| region_size = 1 << 13; /* sectors */ |
| } |
| } else { |
| /* |
| * Validate user-supplied value. |
| */ |
| if (region_size > rs->ti->len) { |
| rs->ti->error = "Supplied region size is too large"; |
| return -EINVAL; |
| } |
| |
| if (region_size < min_region_size) { |
| DMERR("Supplied region_size (%lu sectors) below minimum (%lu)", |
| region_size, min_region_size); |
| rs->ti->error = "Supplied region size is too small"; |
| return -EINVAL; |
| } |
| |
| if (!is_power_of_2(region_size)) { |
| rs->ti->error = "Region size is not a power of 2"; |
| return -EINVAL; |
| } |
| |
| if (region_size < rs->md.chunk_sectors) { |
| rs->ti->error = "Region size is smaller than the chunk size"; |
| return -EINVAL; |
| } |
| } |
| |
| /* |
| * Convert sectors to bytes. |
| */ |
| rs->md.bitmap_info.chunksize = (region_size << 9); |
| |
| return 0; |
| } |
| |
| /* |
| * 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 |
| */ |
| static int parse_raid_params(struct raid_set *rs, char **argv, |
| unsigned num_raid_params) |
| { |
| unsigned i, rebuild_cnt = 0; |
| unsigned long value, region_size = 0; |
| char *key; |
| |
| /* |
| * First, parse the in-order required arguments |
| * "chunk_size" is the only argument of this type. |
| */ |
| if ((strict_strtoul(argv[0], 10, &value) < 0)) { |
| rs->ti->error = "Bad chunk size"; |
| return -EINVAL; |
| } else if (rs->raid_type->level == 1) { |
| 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; |
| argv++; |
| num_raid_params--; |
| |
| /* |
| * We set each individual device as In_sync with a completed |
| * 'recovery_offset'. If there has been a device failure or |
| * replacement then one of the following cases applies: |
| * |
| * 1) User specifies 'rebuild'. |
| * - Device is reset when param is read. |
| * 2) A new device is supplied. |
| * - No matching superblock found, resets device. |
| * 3) Device failure was transient and returns on reload. |
| * - Failure noticed, resets device for bitmap replay. |
| * 4) Device hadn't completed recovery after previous failure. |
| * - Superblock is read and overrides recovery_offset. |
| * |
| * What is found in the superblocks of the devices is always |
| * authoritative, unless 'rebuild' or '[no]sync' was specified. |
| */ |
| for (i = 0; i < rs->md.raid_disks; i++) { |
| set_bit(In_sync, &rs->dev[i].rdev.flags); |
| rs->dev[i].rdev.recovery_offset = MaxSector; |
| } |
| |
| /* |
| * Second, parse the unordered optional arguments |
| */ |
| for (i = 0; i < num_raid_params; i++) { |
| if (!strcasecmp(argv[i], "nosync")) { |
| rs->md.recovery_cp = MaxSector; |
| rs->print_flags |= DMPF_NOSYNC; |
| continue; |
| } |
| if (!strcasecmp(argv[i], "sync")) { |
| rs->md.recovery_cp = 0; |
| rs->print_flags |= DMPF_SYNC; |
| continue; |
| } |
| |
| /* The rest of the optional arguments come in key/value pairs */ |
| if ((i + 1) >= num_raid_params) { |
| rs->ti->error = "Wrong number of raid parameters given"; |
| return -EINVAL; |
| } |
| |
| key = argv[i++]; |
| if (strict_strtoul(argv[i], 10, &value) < 0) { |
| rs->ti->error = "Bad numerical argument given in raid params"; |
| return -EINVAL; |
| } |
| |
| if (!strcasecmp(key, "rebuild")) { |
| rebuild_cnt++; |
| if (((rs->raid_type->level != 1) && |
| (rebuild_cnt > rs->raid_type->parity_devs)) || |
| ((rs->raid_type->level == 1) && |
| (rebuild_cnt > (rs->md.raid_disks - 1)))) { |
| rs->ti->error = "Too many rebuild devices specified for given RAID type"; |
| return -EINVAL; |
| } |
| if (value > rs->md.raid_disks) { |
| rs->ti->error = "Invalid rebuild index given"; |
| return -EINVAL; |
| } |
| clear_bit(In_sync, &rs->dev[value].rdev.flags); |
| rs->dev[value].rdev.recovery_offset = 0; |
| rs->print_flags |= DMPF_REBUILD; |
| } else if (!strcasecmp(key, "write_mostly")) { |
| if (rs->raid_type->level != 1) { |
| rs->ti->error = "write_mostly option is only valid for RAID1"; |
| return -EINVAL; |
| } |
| if (value >= rs->md.raid_disks) { |
| rs->ti->error = "Invalid write_mostly drive index given"; |
| return -EINVAL; |
| } |
| set_bit(WriteMostly, &rs->dev[value].rdev.flags); |
| } else if (!strcasecmp(key, "max_write_behind")) { |
| if (rs->raid_type->level != 1) { |
| rs->ti->error = "max_write_behind option is only valid for RAID1"; |
| return -EINVAL; |
| } |
| rs->print_flags |= DMPF_MAX_WRITE_BEHIND; |
| |
| /* |
| * In device-mapper, we specify things in sectors, but |
| * MD records this value in kB |
| */ |
| value /= 2; |
| if (value > COUNTER_MAX) { |
| rs->ti->error = "Max write-behind limit out of range"; |
| return -EINVAL; |
| } |
| rs->md.bitmap_info.max_write_behind = value; |
| } else if (!strcasecmp(key, "daemon_sleep")) { |
| rs->print_flags |= DMPF_DAEMON_SLEEP; |
| if (!value || (value > MAX_SCHEDULE_TIMEOUT)) { |
| rs->ti->error = "daemon sleep period out of range"; |
| return -EINVAL; |
| } |
| rs->md.bitmap_info.daemon_sleep = value; |
| } else if (!strcasecmp(key, "stripe_cache")) { |
| rs->print_flags |= DMPF_STRIPE_CACHE; |
| |
| /* |
| * In device-mapper, we specify things in sectors, but |
| * MD records this value in kB |
| */ |
| value /= 2; |
| |
| if (rs->raid_type->level < 5) { |
| rs->ti->error = "Inappropriate argument: stripe_cache"; |
| return -EINVAL; |
| } |
| if (raid5_set_cache_size(&rs->md, (int)value)) { |
| rs->ti->error = "Bad stripe_cache size"; |
| return -EINVAL; |
| } |
| } else if (!strcasecmp(key, "min_recovery_rate")) { |
| rs->print_flags |= DMPF_MIN_RECOVERY_RATE; |
| if (value > INT_MAX) { |
| rs->ti->error = "min_recovery_rate out of range"; |
| return -EINVAL; |
| } |
| rs->md.sync_speed_min = (int)value; |
| } else if (!strcasecmp(key, "max_recovery_rate")) { |
| rs->print_flags |= DMPF_MAX_RECOVERY_RATE; |
| if (value > INT_MAX) { |
| rs->ti->error = "max_recovery_rate out of range"; |
| return -EINVAL; |
| } |
| rs->md.sync_speed_max = (int)value; |
| } else if (!strcasecmp(key, "region_size")) { |
| rs->print_flags |= DMPF_REGION_SIZE; |
| region_size = value; |
| } else { |
| DMERR("Unable to parse RAID parameter: %s", key); |
| rs->ti->error = "Unable to parse RAID parameters"; |
| return -EINVAL; |
| } |
| } |
| |
| if (validate_region_size(rs, region_size)) |
| return -EINVAL; |
| |
| if (rs->md.chunk_sectors) |
| rs->ti->split_io = rs->md.chunk_sectors; |
| else |
| rs->ti->split_io = region_size; |
| |
| if (rs->md.chunk_sectors) |
| rs->ti->split_io = rs->md.chunk_sectors; |
| else |
| rs->ti->split_io = region_size; |
| |
| /* Assume there are no metadata devices until the drives are parsed */ |
| rs->md.persistent = 0; |
| rs->md.external = 1; |
| |
| return 0; |
| } |
| |
| static void do_table_event(struct work_struct *ws) |
| { |
| struct raid_set *rs = container_of(ws, struct raid_set, md.event_work); |
| |
| dm_table_event(rs->ti->table); |
| } |
| |
| static int raid_is_congested(struct dm_target_callbacks *cb, int bits) |
| { |
| struct raid_set *rs = container_of(cb, struct raid_set, callbacks); |
| |
| if (rs->raid_type->level == 1) |
| return md_raid1_congested(&rs->md, bits); |
| |
| return md_raid5_congested(&rs->md, bits); |
| } |
| |
| /* |
| * 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 features; /* Used to indicate possible future changes */ |
| |
| __le32 num_devices; /* Number of devices in this array. (Max 64) */ |
| __le32 array_position; /* The position of this drive in the array */ |
| |
| __le64 events; /* Incremented by md when superblock updated */ |
| __le64 failed_devices; /* Bit field of devices to indicate failures */ |
| |
| /* |
| * 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 array |
| * synchronisation/parity calculation. |
| */ |
| __le64 array_resync_offset; |
| |
| /* |
| * RAID characteristics |
| */ |
| __le32 level; |
| __le32 layout; |
| __le32 stripe_sectors; |
| |
| __u8 pad[452]; /* Round struct to 512 bytes. */ |
| /* Always set to 0 when writing. */ |
| } __packed; |
| |
| static int read_disk_sb(struct md_rdev *rdev, int size) |
| { |
| BUG_ON(!rdev->sb_page); |
| |
| if (rdev->sb_loaded) |
| return 0; |
| |
| if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, 1)) { |
| DMERR("Failed to read superblock of device at position %d", |
| rdev->raid_disk); |
| set_bit(Faulty, &rdev->flags); |
| return -EINVAL; |
| } |
| |
| rdev->sb_loaded = 1; |
| |
| return 0; |
| } |
| |
| static void super_sync(struct mddev *mddev, struct md_rdev *rdev) |
| { |
| int i; |
| uint64_t failed_devices; |
| struct dm_raid_superblock *sb; |
| struct raid_set *rs = container_of(mddev, struct raid_set, md); |
| |
| sb = page_address(rdev->sb_page); |
| failed_devices = le64_to_cpu(sb->failed_devices); |
| |
| for (i = 0; i < mddev->raid_disks; i++) |
| if (!rs->dev[i].data_dev || |
| test_bit(Faulty, &(rs->dev[i].rdev.flags))) |
| failed_devices |= (1ULL << i); |
| |
| memset(sb, 0, sizeof(*sb)); |
| |
| sb->magic = cpu_to_le32(DM_RAID_MAGIC); |
| sb->features = cpu_to_le32(0); /* No features yet */ |
| |
| sb->num_devices = cpu_to_le32(mddev->raid_disks); |
| sb->array_position = cpu_to_le32(rdev->raid_disk); |
| |
| sb->events = cpu_to_le64(mddev->events); |
| sb->failed_devices = cpu_to_le64(failed_devices); |
| |
| 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); |
| } |
| |
| /* |
| * 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 ret; |
| struct dm_raid_superblock *sb; |
| struct dm_raid_superblock *refsb; |
| uint64_t events_sb, events_refsb; |
| |
| rdev->sb_start = 0; |
| rdev->sb_size = sizeof(*sb); |
| |
| ret = read_disk_sb(rdev, rdev->sb_size); |
| if (ret) |
| return ret; |
| |
| 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); |
| |
| /* Force writing of superblocks to disk */ |
| set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags); |
| |
| /* Any superblock is better than none, choose that if given */ |
| return refdev ? 0 : 1; |
| } |
| |
| if (!refdev) |
| return 1; |
| |
| events_sb = le64_to_cpu(sb->events); |
| |
| refsb = page_address(refdev->sb_page); |
| events_refsb = le64_to_cpu(refsb->events); |
| |
| return (events_sb > events_refsb) ? 1 : 0; |
| } |
| |
| static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev) |
| { |
| int role; |
| struct raid_set *rs = container_of(mddev, struct raid_set, md); |
| uint64_t events_sb; |
| uint64_t failed_devices; |
| struct dm_raid_superblock *sb; |
| uint32_t new_devs = 0; |
| uint32_t rebuilds = 0; |
| struct md_rdev *r; |
| struct dm_raid_superblock *sb2; |
| |
| sb = page_address(rdev->sb_page); |
| events_sb = le64_to_cpu(sb->events); |
| failed_devices = le64_to_cpu(sb->failed_devices); |
| |
| /* |
| * Initialise to 1 if this is a new superblock. |
| */ |
| mddev->events = events_sb ? : 1; |
| |
| /* |
| * Reshaping is not currently allowed |
| */ |
| if ((le32_to_cpu(sb->level) != mddev->level) || |
| (le32_to_cpu(sb->layout) != mddev->layout) || |
| (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors)) { |
| DMERR("Reshaping arrays not yet supported."); |
| return -EINVAL; |
| } |
| |
| /* We can only change the number of devices in RAID1 right now */ |
| if ((rs->raid_type->level != 1) && |
| (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) { |
| DMERR("Reshaping arrays not yet supported."); |
| return -EINVAL; |
| } |
| |
| if (!(rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC))) |
| mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset); |
| |
| /* |
| * During load, we set FirstUse if a new superblock was written. |
| * There are two reasons we might not have a superblock: |
| * 1) The array is brand new - in which case, all of the |
| * devices must have their In_sync bit set. Also, |
| * recovery_cp must be 0, unless forced. |
| * 2) This is a new device being added to an old array |
| * 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. |
| */ |
| rdev_for_each(r, mddev) { |
| if (!test_bit(In_sync, &r->flags)) { |
| DMINFO("Device %d specified for rebuild: " |
| "Clearing superblock", r->raid_disk); |
| rebuilds++; |
| } else if (test_bit(FirstUse, &r->flags)) |
| new_devs++; |
| } |
| |
| if (!rebuilds) { |
| if (new_devs == mddev->raid_disks) { |
| DMINFO("Superblocks created for new array"); |
| set_bit(MD_ARRAY_FIRST_USE, &mddev->flags); |
| } else if (new_devs) { |
| DMERR("New device injected " |
| "into existing array without 'rebuild' " |
| "parameter specified"); |
| return -EINVAL; |
| } |
| } else if (new_devs) { |
| DMERR("'rebuild' devices cannot be " |
| "injected into an array with other first-time devices"); |
| return -EINVAL; |
| } else if (mddev->recovery_cp != MaxSector) { |
| DMERR("'rebuild' specified while array is not in-sync"); |
| return -EINVAL; |
| } |
| |
| /* |
| * Now we set the Faulty bit for those devices that are |
| * recorded in the superblock as failed. |
| */ |
| rdev_for_each(r, mddev) { |
| if (!r->sb_page) |
| continue; |
| sb2 = page_address(r->sb_page); |
| sb2->failed_devices = 0; |
| |
| /* |
| * 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 != r->raid_disk) { |
| if (rs->raid_type->level != 1) { |
| rs->ti->error = "Cannot change device " |
| "positions in RAID array"; |
| return -EINVAL; |
| } |
| DMINFO("RAID1 device #%d now at position #%d", |
| role, r->raid_disk); |
| } |
| |
| /* |
| * Partial recovery is performed on |
| * returning failed devices. |
| */ |
| if (failed_devices & (1 << role)) |
| set_bit(Faulty, &r->flags); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int super_validate(struct mddev *mddev, struct md_rdev *rdev) |
| { |
| struct dm_raid_superblock *sb = page_address(rdev->sb_page); |
| |
| /* |
| * If mddev->events is not set, we know we have not yet initialized |
| * the array. |
| */ |
| if (!mddev->events && super_init_validation(mddev, rdev)) |
| return -EINVAL; |
| |
| mddev->bitmap_info.offset = 4096 >> 9; /* Enable bitmap creation */ |
| rdev->mddev->bitmap_info.default_offset = 4096 >> 9; |
| if (!test_bit(FirstUse, &rdev->flags)) { |
| rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset); |
| if (rdev->recovery_offset != MaxSector) |
| clear_bit(In_sync, &rdev->flags); |
| } |
| |
| /* |
| * If a device comes back, set it as not In_sync and no longer faulty. |
| */ |
| if (test_bit(Faulty, &rdev->flags)) { |
| clear_bit(Faulty, &rdev->flags); |
| clear_bit(In_sync, &rdev->flags); |
| rdev->saved_raid_disk = rdev->raid_disk; |
| rdev->recovery_offset = 0; |
| } |
| |
| clear_bit(FirstUse, &rdev->flags); |
| |
| return 0; |
| } |
| |
| /* |
| * Analyse superblocks and select the freshest. |
| */ |
| static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs) |
| { |
| int ret; |
| unsigned redundancy = 0; |
| struct raid_dev *dev; |
| struct md_rdev *rdev, *tmp, *freshest; |
| struct mddev *mddev = &rs->md; |
| |
| switch (rs->raid_type->level) { |
| case 1: |
| redundancy = rs->md.raid_disks - 1; |
| break; |
| case 4: |
| case 5: |
| case 6: |
| redundancy = rs->raid_type->parity_devs; |
| break; |
| default: |
| ti->error = "Unknown RAID type"; |
| return -EINVAL; |
| } |
| |
| freshest = NULL; |
| rdev_for_each_safe(rdev, tmp, mddev) { |
| if (!rdev->meta_bdev) |
| continue; |
| |
| ret = super_load(rdev, freshest); |
| |
| switch (ret) { |
| case 1: |
| freshest = rdev; |
| break; |
| case 0: |
| break; |
| default: |
| dev = container_of(rdev, struct raid_dev, rdev); |
| if (redundancy--) { |
| if (dev->meta_dev) |
| dm_put_device(ti, dev->meta_dev); |
| |
| dev->meta_dev = NULL; |
| rdev->meta_bdev = NULL; |
| |
| if (rdev->sb_page) |
| put_page(rdev->sb_page); |
| |
| rdev->sb_page = NULL; |
| |
| rdev->sb_loaded = 0; |
| |
| /* |
| * We might be able to salvage the data device |
| * even though the meta device has failed. For |
| * now, we behave as though '- -' had been |
| * set for this device in the table. |
| */ |
| if (dev->data_dev) |
| dm_put_device(ti, dev->data_dev); |
| |
| dev->data_dev = NULL; |
| rdev->bdev = NULL; |
| |
| list_del(&rdev->same_set); |
| |
| continue; |
| } |
| ti->error = "Failed to load superblock"; |
| return ret; |
| } |
| } |
| |
| if (!freshest) |
| return 0; |
| |
| /* |
| * Validation of the freshest device provides the source of |
| * validation for the remaining devices. |
| */ |
| ti->error = "Unable to assemble array: Invalid superblocks"; |
| if (super_validate(mddev, freshest)) |
| return -EINVAL; |
| |
| rdev_for_each(rdev, mddev) |
| if ((rdev != freshest) && super_validate(mddev, rdev)) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| /* |
| * Construct a RAID4/5/6 mapping: |
| * Args: |
| * <raid_type> <#raid_params> <raid_params> \ |
| * <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> } |
| * |
| * <raid_params> varies by <raid_type>. See 'parse_raid_params' for |
| * details on possible <raid_params>. |
| */ |
| static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv) |
| { |
| int ret; |
| struct raid_type *rt; |
| unsigned long num_raid_params, num_raid_devs; |
| struct raid_set *rs = NULL; |
| |
| /* Must have at least <raid_type> <#raid_params> */ |
| if (argc < 2) { |
| ti->error = "Too few arguments"; |
| return -EINVAL; |
| } |
| |
| /* raid type */ |
| rt = get_raid_type(argv[0]); |
| if (!rt) { |
| ti->error = "Unrecognised raid_type"; |
| return -EINVAL; |
| } |
| argc--; |
| argv++; |
| |
| /* number of RAID parameters */ |
| if (strict_strtoul(argv[0], 10, &num_raid_params) < 0) { |
| ti->error = "Cannot understand number of RAID parameters"; |
| return -EINVAL; |
| } |
| argc--; |
| argv++; |
| |
| /* Skip over RAID params for now and find out # of devices */ |
| if (num_raid_params + 1 > argc) { |
| ti->error = "Arguments do not agree with counts given"; |
| return -EINVAL; |
| } |
| |
| if ((strict_strtoul(argv[num_raid_params], 10, &num_raid_devs) < 0) || |
| (num_raid_devs >= INT_MAX)) { |
| ti->error = "Cannot understand number of raid devices"; |
| return -EINVAL; |
| } |
| |
| rs = context_alloc(ti, rt, (unsigned)num_raid_devs); |
| if (IS_ERR(rs)) |
| return PTR_ERR(rs); |
| |
| ret = parse_raid_params(rs, argv, (unsigned)num_raid_params); |
| if (ret) |
| goto bad; |
| |
| ret = -EINVAL; |
| |
| argc -= num_raid_params + 1; /* +1: we already have num_raid_devs */ |
| argv += num_raid_params + 1; |
| |
| if (argc != (num_raid_devs * 2)) { |
| ti->error = "Supplied RAID devices does not match the count given"; |
| goto bad; |
| } |
| |
| ret = dev_parms(rs, argv); |
| if (ret) |
| goto bad; |
| |
| rs->md.sync_super = super_sync; |
| ret = analyse_superblocks(ti, rs); |
| if (ret) |
| goto bad; |
| |
| INIT_WORK(&rs->md.event_work, do_table_event); |
| ti->private = rs; |
| ti->num_flush_requests = 1; |
| |
| mutex_lock(&rs->md.reconfig_mutex); |
| ret = md_run(&rs->md); |
| rs->md.in_sync = 0; /* Assume already marked dirty */ |
| mutex_unlock(&rs->md.reconfig_mutex); |
| |
| if (ret) { |
| ti->error = "Fail to run raid array"; |
| goto bad; |
| } |
| |
| rs->callbacks.congested_fn = raid_is_congested; |
| dm_table_add_target_callbacks(ti->table, &rs->callbacks); |
| |
| mddev_suspend(&rs->md); |
| return 0; |
| |
| bad: |
| context_free(rs); |
| |
| return ret; |
| } |
| |
| static void raid_dtr(struct dm_target *ti) |
| { |
| struct raid_set *rs = ti->private; |
| |
| list_del_init(&rs->callbacks.list); |
| md_stop(&rs->md); |
| context_free(rs); |
| } |
| |
| static int raid_map(struct dm_target *ti, struct bio *bio, union map_info *map_context) |
| { |
| struct raid_set *rs = ti->private; |
| struct mddev *mddev = &rs->md; |
| |
| mddev->pers->make_request(mddev, bio); |
| |
| return DM_MAPIO_SUBMITTED; |
| } |
| |
| static int raid_status(struct dm_target *ti, status_type_t type, |
| char *result, unsigned maxlen) |
| { |
| struct raid_set *rs = ti->private; |
| unsigned raid_param_cnt = 1; /* at least 1 for chunksize */ |
| unsigned sz = 0; |
| int i, array_in_sync = 0; |
| sector_t sync; |
| |
| switch (type) { |
| case STATUSTYPE_INFO: |
| DMEMIT("%s %d ", rs->raid_type->name, rs->md.raid_disks); |
| |
| if (test_bit(MD_RECOVERY_RUNNING, &rs->md.recovery)) |
| sync = rs->md.curr_resync_completed; |
| else |
| sync = rs->md.recovery_cp; |
| |
| if (sync >= rs->md.resync_max_sectors) { |
| array_in_sync = 1; |
| sync = rs->md.resync_max_sectors; |
| } else { |
| /* |
| * The array may be doing an initial sync, or it may |
| * be rebuilding individual components. If all the |
| * devices are In_sync, then it is the array that is |
| * being initialized. |
| */ |
| for (i = 0; i < rs->md.raid_disks; i++) |
| if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) |
| array_in_sync = 1; |
| } |
| /* |
| * Status characters: |
| * 'D' = Dead/Failed device |
| * 'a' = Alive but not in-sync |
| * 'A' = Alive and in-sync |
| */ |
| for (i = 0; i < rs->md.raid_disks; i++) { |
| if (test_bit(Faulty, &rs->dev[i].rdev.flags)) |
| DMEMIT("D"); |
| else if (!array_in_sync || |
| !test_bit(In_sync, &rs->dev[i].rdev.flags)) |
| DMEMIT("a"); |
| else |
| DMEMIT("A"); |
| } |
| |
| /* |
| * In-sync ratio: |
| * The in-sync ratio shows the progress of: |
| * - Initializing the array |
| * - Rebuilding a subset of devices of the array |
| * The user can distinguish between the two by referring |
| * to the status characters. |
| */ |
| DMEMIT(" %llu/%llu", |
| (unsigned long long) sync, |
| (unsigned long long) rs->md.resync_max_sectors); |
| |
| break; |
| case STATUSTYPE_TABLE: |
| /* The string you would use to construct this array */ |
| for (i = 0; i < rs->md.raid_disks; i++) { |
| if ((rs->print_flags & DMPF_REBUILD) && |
| rs->dev[i].data_dev && |
| !test_bit(In_sync, &rs->dev[i].rdev.flags)) |
| raid_param_cnt += 2; /* for rebuilds */ |
| if (rs->dev[i].data_dev && |
| test_bit(WriteMostly, &rs->dev[i].rdev.flags)) |
| raid_param_cnt += 2; |
| } |
| |
| raid_param_cnt += (hweight32(rs->print_flags & ~DMPF_REBUILD) * 2); |
| if (rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC)) |
| raid_param_cnt--; |
| |
| DMEMIT("%s %u %u", rs->raid_type->name, |
| raid_param_cnt, rs->md.chunk_sectors); |
| |
| if ((rs->print_flags & DMPF_SYNC) && |
| (rs->md.recovery_cp == MaxSector)) |
| DMEMIT(" sync"); |
| if (rs->print_flags & DMPF_NOSYNC) |
| DMEMIT(" nosync"); |
| |
| for (i = 0; i < rs->md.raid_disks; i++) |
| if ((rs->print_flags & DMPF_REBUILD) && |
| rs->dev[i].data_dev && |
| !test_bit(In_sync, &rs->dev[i].rdev.flags)) |
| DMEMIT(" rebuild %u", i); |
| |
| if (rs->print_flags & DMPF_DAEMON_SLEEP) |
| DMEMIT(" daemon_sleep %lu", |
| rs->md.bitmap_info.daemon_sleep); |
| |
| if (rs->print_flags & DMPF_MIN_RECOVERY_RATE) |
| DMEMIT(" min_recovery_rate %d", rs->md.sync_speed_min); |
| |
| if (rs->print_flags & DMPF_MAX_RECOVERY_RATE) |
| DMEMIT(" max_recovery_rate %d", rs->md.sync_speed_max); |
| |
| for (i = 0; i < rs->md.raid_disks; i++) |
| if (rs->dev[i].data_dev && |
| test_bit(WriteMostly, &rs->dev[i].rdev.flags)) |
| DMEMIT(" write_mostly %u", i); |
| |
| if (rs->print_flags & DMPF_MAX_WRITE_BEHIND) |
| DMEMIT(" max_write_behind %lu", |
| rs->md.bitmap_info.max_write_behind); |
| |
| if (rs->print_flags & DMPF_STRIPE_CACHE) { |
| struct r5conf *conf = rs->md.private; |
| |
| /* convert from kiB to sectors */ |
| DMEMIT(" stripe_cache %d", |
| conf ? conf->max_nr_stripes * 2 : 0); |
| } |
| |
| if (rs->print_flags & DMPF_REGION_SIZE) |
| DMEMIT(" region_size %lu", |
| rs->md.bitmap_info.chunksize >> 9); |
| |
| DMEMIT(" %d", rs->md.raid_disks); |
| for (i = 0; i < rs->md.raid_disks; i++) { |
| if (rs->dev[i].meta_dev) |
| DMEMIT(" %s", rs->dev[i].meta_dev->name); |
| else |
| DMEMIT(" -"); |
| |
| if (rs->dev[i].data_dev) |
| DMEMIT(" %s", rs->dev[i].data_dev->name); |
| else |
| DMEMIT(" -"); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int raid_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data) |
| { |
| struct raid_set *rs = ti->private; |
| unsigned i; |
| int ret = 0; |
| |
| for (i = 0; !ret && i < rs->md.raid_disks; i++) |
| if (rs->dev[i].data_dev) |
| ret = fn(ti, |
| rs->dev[i].data_dev, |
| 0, /* No offset on data devs */ |
| rs->md.dev_sectors, |
| data); |
| |
| return ret; |
| } |
| |
| static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) |
| { |
| struct raid_set *rs = ti->private; |
| unsigned chunk_size = rs->md.chunk_sectors << 9; |
| struct r5conf *conf = rs->md.private; |
| |
| blk_limits_io_min(limits, chunk_size); |
| blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded)); |
| } |
| |
| static void raid_presuspend(struct dm_target *ti) |
| { |
| struct raid_set *rs = ti->private; |
| |
| md_stop_writes(&rs->md); |
| } |
| |
| static void raid_postsuspend(struct dm_target *ti) |
| { |
| struct raid_set *rs = ti->private; |
| |
| mddev_suspend(&rs->md); |
| } |
| |
| static void raid_resume(struct dm_target *ti) |
| { |
| struct raid_set *rs = ti->private; |
| |
| set_bit(MD_CHANGE_DEVS, &rs->md.flags); |
| if (!rs->bitmap_loaded) { |
| bitmap_load(&rs->md); |
| rs->bitmap_loaded = 1; |
| } |
| |
| clear_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); |
| mddev_resume(&rs->md); |
| } |
| |
| static struct target_type raid_target = { |
| .name = "raid", |
| .version = {1, 2, 0}, |
| .module = THIS_MODULE, |
| .ctr = raid_ctr, |
| .dtr = raid_dtr, |
| .map = raid_map, |
| .status = raid_status, |
| .iterate_devices = raid_iterate_devices, |
| .io_hints = raid_io_hints, |
| .presuspend = raid_presuspend, |
| .postsuspend = raid_postsuspend, |
| .resume = raid_resume, |
| }; |
| |
| static int __init dm_raid_init(void) |
| { |
| 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_DESCRIPTION(DM_NAME " raid4/5/6 target"); |
| MODULE_ALIAS("dm-raid4"); |
| MODULE_ALIAS("dm-raid5"); |
| MODULE_ALIAS("dm-raid6"); |
| MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>"); |
| MODULE_LICENSE("GPL"); |