diff options
Diffstat (limited to 'drivers/md/raid10.c')
| -rw-r--r-- | drivers/md/raid10.c | 890 |
1 files changed, 867 insertions, 23 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index f102e88fc785..ec271ae4318f 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -24,6 +24,7 @@ #include <linux/module.h> #include <linux/seq_file.h> #include <linux/ratelimit.h> +#include <linux/kthread.h> #include "md.h" #include "raid10.h" #include "raid0.h" @@ -68,6 +69,11 @@ static int max_queued_requests = 1024; static void allow_barrier(struct r10conf *conf); static void lower_barrier(struct r10conf *conf); static int enough(struct r10conf *conf, int ignore); +static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, + int *skipped); +static void reshape_request_write(struct mddev *mddev, struct r10bio *r10_bio); +static void end_reshape_write(struct bio *bio, int error); +static void end_reshape(struct r10conf *conf); static void * r10bio_pool_alloc(gfp_t gfp_flags, void *data) { @@ -112,7 +118,8 @@ static void * r10buf_pool_alloc(gfp_t gfp_flags, void *data) if (!r10_bio) return NULL; - if (test_bit(MD_RECOVERY_SYNC, &conf->mddev->recovery)) + if (test_bit(MD_RECOVERY_SYNC, &conf->mddev->recovery) || + test_bit(MD_RECOVERY_RESHAPE, &conf->mddev->recovery)) nalloc = conf->copies; /* resync */ else nalloc = 2; /* recovery */ @@ -140,9 +147,10 @@ static void * r10buf_pool_alloc(gfp_t gfp_flags, void *data) struct bio *rbio = r10_bio->devs[j].repl_bio; bio = r10_bio->devs[j].bio; for (i = 0; i < RESYNC_PAGES; i++) { - if (j == 1 && !test_bit(MD_RECOVERY_SYNC, - &conf->mddev->recovery)) { - /* we can share bv_page's during recovery */ + if (j > 0 && !test_bit(MD_RECOVERY_SYNC, + &conf->mddev->recovery)) { + /* we can share bv_page's during recovery + * and reshape */ struct bio *rbio = r10_bio->devs[0].bio; page = rbio->bi_io_vec[i].bv_page; get_page(page); @@ -614,10 +622,11 @@ static int raid10_mergeable_bvec(struct request_queue *q, struct r10conf *conf = mddev->private; sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); int max; - unsigned int chunk_sectors = mddev->chunk_sectors; + unsigned int chunk_sectors; unsigned int bio_sectors = bvm->bi_size >> 9; struct geom *geo = &conf->geo; + chunk_sectors = (conf->geo.chunk_mask & conf->prev.chunk_mask) + 1; if (conf->reshape_progress != MaxSector && ((sector >= conf->reshape_progress) != conf->mddev->reshape_backwards)) @@ -1032,6 +1041,7 @@ static void make_request(struct mddev *mddev, struct bio * bio) int plugged; int sectors_handled; int max_sectors; + int sectors; if (unlikely(bio->bi_rw & REQ_FLUSH)) { md_flush_request(mddev, bio); @@ -1096,10 +1106,41 @@ static void make_request(struct mddev *mddev, struct bio * bio) */ wait_barrier(conf); + sectors = bio->bi_size >> 9; + while (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) && + bio->bi_sector < conf->reshape_progress && + bio->bi_sector + sectors > conf->reshape_progress) { + /* IO spans the reshape position. Need to wait for + * reshape to pass + */ + allow_barrier(conf); + wait_event(conf->wait_barrier, + conf->reshape_progress <= bio->bi_sector || + conf->reshape_progress >= bio->bi_sector + sectors); + wait_barrier(conf); + } + if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) && + bio_data_dir(bio) == WRITE && + (mddev->reshape_backwards + ? (bio->bi_sector < conf->reshape_safe && + bio->bi_sector + sectors > conf->reshape_progress) + : (bio->bi_sector + sectors > conf->reshape_safe && + bio->bi_sector < conf->reshape_progress))) { + /* Need to update reshape_position in metadata */ + mddev->reshape_position = conf->reshape_progress; + set_bit(MD_CHANGE_DEVS, &mddev->flags); + set_bit(MD_CHANGE_PENDING, &mddev->flags); + md_wakeup_thread(mddev->thread); + wait_event(mddev->sb_wait, + !test_bit(MD_CHANGE_PENDING, &mddev->flags)); + + conf->reshape_safe = mddev->reshape_position; + } + r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO); r10_bio->master_bio = bio; - r10_bio->sectors = bio->bi_size >> 9; + r10_bio->sectors = sectors; r10_bio->mddev = mddev; r10_bio->sector = bio->bi_sector; @@ -1730,7 +1771,11 @@ static void end_sync_read(struct bio *bio, int error) struct r10conf *conf = r10_bio->mddev->private; int d; - d = find_bio_disk(conf, r10_bio, bio, NULL, NULL); + if (bio == r10_bio->master_bio) { + /* this is a reshape read */ + d = r10_bio->read_slot; /* really the read dev */ + } else + d = find_bio_disk(conf, r10_bio, bio, NULL, NULL); if (test_bit(BIO_UPTODATE, &bio->bi_flags)) set_bit(R10BIO_Uptodate, &r10_bio->state); @@ -2631,6 +2676,8 @@ static void raid10d(struct mddev *mddev) if (test_bit(R10BIO_MadeGood, &r10_bio->state) || test_bit(R10BIO_WriteError, &r10_bio->state)) handle_write_completed(conf, r10_bio); + else if (test_bit(R10BIO_IsReshape, &r10_bio->state)) + reshape_request_write(mddev, r10_bio); else if (test_bit(R10BIO_IsSync, &r10_bio->state)) sync_request_write(mddev, r10_bio); else if (test_bit(R10BIO_IsRecover, &r10_bio->state)) @@ -2723,7 +2770,8 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, skipped: max_sector = mddev->dev_sectors; - if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) + if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) || + test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) max_sector = mddev->resync_max_sectors; if (sector_nr >= max_sector) { /* If we aborted, we need to abort the @@ -2735,6 +2783,11 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, * we need to convert that to several * virtual addresses. */ + if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { + end_reshape(conf); + return 0; + } + if (mddev->curr_resync < max_sector) { /* aborted */ if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) bitmap_end_sync(mddev->bitmap, mddev->curr_resync, @@ -2766,6 +2819,10 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, *skipped = 1; return sectors_skipped; } + + if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) + return reshape_request(mddev, sector_nr, skipped); + if (chunks_skipped >= conf->geo.raid_disks) { /* if there has been nothing to do on any drive, * then there is nothing to do at all.. @@ -3211,7 +3268,8 @@ raid10_size(struct mddev *mddev, sector_t sectors, int raid_disks) struct r10conf *conf = mddev->private; if (!raid_disks) - raid_disks = conf->geo.raid_disks; + raid_disks = min(conf->geo.raid_disks, + conf->prev.raid_disks); if (!sectors) sectors = conf->dev_sectors; @@ -3321,7 +3379,9 @@ static struct r10conf *setup_conf(struct mddev *mddev) if (!conf) goto out; - conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks, + /* FIXME calc properly */ + conf->mirrors = kzalloc(sizeof(struct mirror_info)*(mddev->raid_disks + + max(0,mddev->delta_disks)), GFP_KERNEL); if (!conf->mirrors) goto out; @@ -3338,9 +3398,21 @@ static struct r10conf *setup_conf(struct mddev *mddev) goto out; calc_sectors(conf, mddev->dev_sectors); - conf->prev = conf->geo; - conf->reshape_progress = MaxSector; - + if (mddev->reshape_position == MaxSector) { + conf->prev = conf->geo; + conf->reshape_progress = MaxSector; + } else { + if (setup_geo(&conf->prev, mddev, geo_old) != conf->copies) { + err = -EINVAL; + goto out; + } + conf->reshape_progress = mddev->reshape_position; + if (conf->prev.far_offset) + conf->prev.stride = 1 << conf->prev.chunk_shift; + else + /* far_copies must be 1 */ + conf->prev.stride = conf->dev_sectors; + } spin_lock_init(&conf->device_lock); INIT_LIST_HEAD(&conf->retry_list); @@ -3355,8 +3427,9 @@ static struct r10conf *setup_conf(struct mddev *mddev) return conf; out: - printk(KERN_ERR "md/raid10:%s: couldn't allocate memory.\n", - mdname(mddev)); + if (err == -ENOMEM) + printk(KERN_ERR "md/raid10:%s: couldn't allocate memory.\n", + mdname(mddev)); if (conf) { if (conf->r10bio_pool) mempool_destroy(conf->r10bio_pool); @@ -3374,12 +3447,8 @@ static int run(struct mddev *mddev) struct mirror_info *disk; struct md_rdev *rdev; sector_t size; - - /* - * copy the already verified devices into our private RAID10 - * bookkeeping area. [whatever we allocate in run(), - * should be freed in stop()] - */ + sector_t min_offset_diff = 0; + int first = 1; if (mddev->private == NULL) { conf = setup_conf(mddev); @@ -3403,6 +3472,7 @@ static int run(struct mddev *mddev) (conf->geo.raid_disks / conf->geo.near_copies)); rdev_for_each(rdev, mddev) { + long long diff; disk_idx = rdev->raid_disk; if (disk_idx < 0) @@ -3421,12 +3491,20 @@ static int run(struct mddev *mddev) goto out_free_conf; disk->rdev = rdev; } + diff = (rdev->new_data_offset - rdev->data_offset); + if (!mddev->reshape_backwards) + diff = -diff; + if (diff < 0) + diff = 0; + if (first || diff < min_offset_diff) + min_offset_diff = diff; disk_stack_limits(mddev->gendisk, rdev->bdev, rdev->data_offset << 9); disk->head_position = 0; } + /* need to check that every block has at least one working mirror */ if (!enough(conf, -1)) { printk(KERN_ERR "md/raid10:%s: not enough operational mirrors.\n", @@ -3434,6 +3512,16 @@ static int run(struct mddev *mddev) goto out_free_conf; } + if (conf->reshape_progress != MaxSector) { + /* must ensure that shape change is supported */ + if (conf->geo.far_copies != 1 && + conf->geo.far_offset == 0) + goto out_free_conf; + if (conf->prev.far_copies != 1 && + conf->geo.far_offset == 0) + goto out_free_conf; + } + mddev->degraded = 0; for (i = 0; i < conf->geo.raid_disks @@ -3486,8 +3574,8 @@ static int run(struct mddev *mddev) int stripe = conf->geo.raid_disks * ((mddev->chunk_sectors << 9) / PAGE_SIZE); stripe /= conf->geo.near_copies; - if (mddev->queue->backing_dev_info.ra_pages < 2* stripe) - mddev->queue->backing_dev_info.ra_pages = 2* stripe; + if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) + mddev->queue->backing_dev_info.ra_pages = 2 * stripe; } blk_queue_merge_bvec(mddev->queue, raid10_mergeable_bvec); @@ -3495,6 +3583,30 @@ static int run(struct mddev *mddev) if (md_integrity_register(mddev)) goto out_free_conf; + if (conf->reshape_progress != MaxSector) { + unsigned long before_length, after_length; + + before_length = ((1 << conf->prev.chunk_shift) * + conf->prev.far_copies); + after_length = ((1 << conf->geo.chunk_shift) * + conf->geo.far_copies); + + if (max(before_length, after_length) > min_offset_diff) { + /* This cannot work */ + printk("md/raid10: offset difference not enough to continue reshape\n"); + goto out_free_conf; + } + conf->offset_diff = min_offset_diff; + + conf->reshape_safe = conf->reshape_progress; + clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); + clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); + set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); + set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); + mddev->sync_thread = md_register_thread(md_do_sync, mddev, + "reshape"); + } + return 0; out_free_conf: @@ -3634,6 +3746,735 @@ static void *raid10_takeover(struct mddev *mddev) return ERR_PTR(-EINVAL); } +static int raid10_check_reshape(struct mddev *mddev) +{ + /* Called when there is a request to change + * - layout (to ->new_layout) + * - chunk size (to ->new_chunk_sectors) + * - raid_disks (by delta_disks) + * or when trying to restart a reshape that was ongoing. + * + * We need to validate the request and possibly allocate + * space if that might be an issue later. + * + * Currently we reject any reshape of a 'far' mode array, + * allow chunk size to change if new is generally acceptable, + * allow raid_disks to increase, and allow + * a switch between 'near' mode and 'offset' mode. + */ + struct r10conf *conf = mddev->private; + struct geom geo; + + if (conf->geo.far_copies != 1 && !conf->geo.far_offset) + return -EINVAL; + + if (setup_geo(&geo, mddev, geo_start) != conf->copies) + /* mustn't change number of copies */ + return -EINVAL; + if (geo.far_copies > 1 && !geo.far_offset) + /* Cannot switch to 'far' mode */ + return -EINVAL; + + if (mddev->array_sectors & geo.chunk_mask) + /* not factor of array size */ + return -EINVAL; + + if (mddev->bitmap) + return -EBUSY; + if (!enough(conf, -1)) + return -EINVAL; + + kfree(conf->mirrors_new); + conf->mirrors_new = NULL; + if (mddev->delta_disks > 0) { + /* allocate new 'mirrors' list */ + conf->mirrors_new = kzalloc( + sizeof(struct mirror_info) + *(mddev->raid_disks + + mddev->delta_disks), + GFP_KERNEL); + if (!conf->mirrors_new) + return -ENOMEM; + } + return 0; +} + +/* + * Need to check if array has failed when deciding whether to: + * - start an array + * - remove non-faulty devices + * - add a spare + * - allow a reshape + * This determination is simple when no reshape is happening. + * However if there is a reshape, we need to carefully check + * both the before and after sections. + * This is because some failed devices may only affect one + * of the two sections, and some non-in_sync devices may + * be insync in the section most affected by failed devices. + */ +static int calc_degraded(struct r10conf *conf) +{ + int degraded, degraded2; + int i; + + rcu_read_lock(); + degraded = 0; + /* 'prev' section first */ + for (i = 0; i < conf->prev.raid_disks; i++) { + struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); + if (!rdev || test_bit(Faulty, &rdev->flags)) + degraded++; + else if (!test_bit(In_sync, &rdev->flags)) + /* When we can reduce the number of devices in + * an array, this might not contribute to + * 'degraded'. It does now. + */ + degraded++; + } + rcu_read_unlock(); + if (conf->geo.raid_disks == conf->prev.raid_disks) + return degraded; + rcu_read_lock(); + degraded2 = 0; + for (i = 0; i < conf->geo.raid_disks; i++) { + struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); + if (!rdev || test_bit(Faulty, &rdev->flags)) + degraded2++; + else if (!test_bit(In_sync, &rdev->flags)) { + /* If reshape is increasing the number of devices, + * this section has already been recovered, so + * it doesn't contribute to degraded. + * else it does. + */ + if (conf->geo.raid_disks <= conf->prev.raid_disks) + degraded2++; + } + } + rcu_read_unlock(); + if (degraded2 > degraded) + return degraded2; + return degraded; +} + +static int raid10_start_reshape(struct mddev *mddev) +{ + /* A 'reshape' has been requested. This commits + * the various 'new' fields and sets MD_RECOVER_RESHAPE + * This also checks if there are enough spares and adds them + * to the array. + * We currently require enough spares to make the final + * array non-degraded. We also require that the difference + * between old and new data_offset - on each device - is + * enough that we never risk over-writing. + */ + + unsigned long before_length, after_length; + sector_t min_offset_diff = 0; + int first = 1; + struct geom new; + struct r10conf *conf = mddev->private; + struct md_rdev *rdev; + int spares = 0; + + if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) + return -EBUSY; + + if (setup_geo(&new, mddev, geo_start) != conf->copies) + return -EINVAL; + + before_length = ((1 << conf->prev.chunk_shift) * + conf->prev.far_copies); + after_length = ((1 << conf->geo.chunk_shift) * + conf->geo.far_copies); + + rdev_for_each(rdev, mddev) { + if (!test_bit(In_sync, &rdev->flags) + && !test_bit(Faulty, &rdev->flags)) + spares++; + if (rdev->raid_disk >= 0) { + long long diff = (rdev->new_data_offset + - rdev->data_offset); + if (!mddev->reshape_backwards) + diff = -diff; + if (diff < 0) + diff = 0; + if (first || diff < min_offset_diff) + min_offset_diff = diff; + } + } + + if (max(before_length, after_length) > min_offset_diff) + return -EINVAL; + + if (spares < mddev->delta_disks) + return -EINVAL; + + conf->offset_diff = min_offset_diff; + spin_lock_irq(&conf->device_lock); + if (conf->mirrors_new) { + memcpy(conf->mirrors_new, conf->mirrors, + sizeof(struct mirror_info)*conf->prev.raid_disks); + smp_mb(); + kfree(conf->mirrors_old); /* FIXME and elsewhere */ + conf->mirrors_old = conf->mirrors; + conf->mirrors = conf->mirrors_new; + conf->mirrors_new = NULL; + } + setup_geo(&conf->geo, mddev, geo_start); + smp_mb(); + if (mddev->reshape_backwards) { + sector_t size = raid10_size(mddev, 0, 0); + if (size < mddev->array_sectors) { + spin_unlock_irq(&conf->device_lock); + printk(KERN_ERR "md/raid10:%s: array size must be reduce before number of disks\n", + mdname(mddev)); + return -EINVAL; + } + mddev->resync_max_sectors = size; + conf->reshape_progress = size; + } else + conf->reshape_progress = 0; + spin_unlock_irq(&conf->device_lock); + + if (mddev->delta_disks > 0) { + rdev_for_each(rdev, mddev) + if (rdev->raid_disk < 0 && + !test_bit(Faulty, &rdev->flags)) { + if (raid10_add_disk(mddev, rdev) == 0) { + if (rdev->raid_disk >= + conf->prev.raid_disks) + set_bit(In_sync, &rdev->flags); + else + rdev->recovery_offset = 0; + + if (sysfs_link_rdev(mddev, rdev)) + /* Failure here is OK */; + } + } else if (rdev->raid_disk >= conf->prev.raid_disks + && !test_bit(Faulty, &rdev->flags)) { + /* This is a spare that was manually added */ + set_bit(In_sync, &rdev->flags); + } + } + /* When a reshape changes the number of devices, + * ->degraded is measured against the larger of the + * pre and post numbers. + */ + spin_lock_irq(&conf->device_lock); + mddev->degraded = calc_degraded(conf); + spin_unlock_irq(&conf->device_lock); + mddev->raid_disks = conf->geo.raid_disks; + mddev->reshape_position = conf->reshape_progress; + set_bit(MD_CHANGE_DEVS, &mddev->flags); + + clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); + clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); + set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); + set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); + + mddev->sync_thread = md_register_thread(md_do_sync, mddev, + "reshape"); + if (!mddev->sync_thread) { + mddev->recovery = 0; + spin_lock_irq(&conf->device_lock); + conf->geo = conf->prev; + mddev->raid_disks = conf->geo.raid_disks; + rdev_for_each(rdev, mddev) + rdev->new_data_offset = rdev->data_offset; + smp_wmb(); + conf->reshape_progress = MaxSector; + mddev->reshape_position = MaxSector; + spin_unlock_irq(&conf->device_lock); + return -EAGAIN; + } + conf->reshape_checkpoint = jiffies; + md_wakeup_thread(mddev->sync_thread); + md_new_event(mddev); + return 0; +} + +/* Calculate the last device-address that could contain + * any block from the chunk that includes the array-address 's' + * and report the next address. + * i.e. the address returned will be chunk-aligned and after + * any data that is in the chunk containing 's'. + */ +static sector_t last_dev_address(sector_t s, struct geom *geo) +{ + s = (s | geo->chunk_mask) + 1; + s >>= geo->chunk_shift; + s *= geo->near_copies; + s = DIV_ROUND_UP_SECTOR_T(s, geo->raid_disks); + s *= geo->far_copies; + s <<= geo->chunk_shift; + return s; +} + +/* Calculate the first device-address that could contain + * any block from the chunk that includes the array-address 's'. + * This too will be the start of a chunk + */ +static sector_t first_dev_address(sector_t s, struct geom *geo) +{ + s >>= geo->chunk_shift; + s *= geo->near_copies; + sector_div(s, geo->raid_disks); + s *= geo->far_copies; + s <<= geo->chunk_shift; + return s; +} + +static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, + int *skipped) +{ + /* We simply copy at most one chunk (smallest of old and new) + * at a time, possibly less if that exceeds RESYNC_PAGES, + * or we hit a bad block or something. + * This might mean we pause for normal IO in the middle of + * a chunk, but that is not a problem was mddev->reshape_position + * can record any location. + * + * If we will want to write to a location that isn't + * yet recorded as 'safe' (i.e. in metadata on disk) then + * we need to flush all reshape requests and update the metadata. + * + * When reshaping forwards (e.g. to more devices), we interpret + * 'safe' as the earliest block which might not have been copied + * down yet. We divide this by previous stripe size and multiply + * by previous stripe length to get lowest device offset that we + * cannot write to yet. + * We interpret 'sector_nr' as an address that we want to write to. + * From this we use last_device_address() to find where we might + * write to, and first_device_address on the 'safe' position. + * If this 'next' write position is after the 'safe' position, + * we must update the metadata to increase the 'safe' position. + * + * When reshaping backwards, we round in the opposite direction + * and perform the reverse test: next write position must not be + * less than current safe position. + * + * In all this the minimum difference in data offsets + * (conf->offset_diff - always positive) allows a bit of slack, + * so next can be after 'safe', but not by more than offset_disk + * + * We need to prepare all the bios here before we start any IO + * to ensure the size we choose is acceptable to all devices. + * The means one for each copy for write-out and an extra one for + * read-in. + * We store the read-in bio in ->master_bio and the others in + * ->devs[x].bio and ->devs[x].repl_bio. + */ + struct r10conf *conf = mddev->private; + struct r10bio *r10_bio; + sector_t next, safe, last; + int max_sectors; + int nr_sectors; + int s; + struct md_rdev *rdev; + int need_flush = 0; + struct bio *blist; + struct bio *bio, *read_bio; + int sectors_done = 0; + + if (sector_nr == 0) { + /* If restarting in the middle, skip the initial sectors */ + if (mddev->reshape_backwards && + conf->reshape_progress < raid10_size(mddev, 0, 0)) { + sector_nr = (raid10_size(mddev, 0, 0) + - conf->reshape_progress); + } else if (!mddev->reshape_backwards && + conf->reshape_progress > 0) + sector_nr = conf->reshape_progress; + if (sector_nr) { + mddev->curr_resync_completed = sector_nr; + sysfs_notify(&mddev->kobj, NULL, "sync_completed"); + *skipped = 1; + return sector_nr; + } + } + + /* We don't use sector_nr to track where we are up to + * as that doesn't work well for ->reshape_backwards. + * So just use ->reshape_progress. + */ + if (mddev->reshape_backwards) { + /* 'next' is the earliest device address that we might + * write to for this chunk in the new layout + */ + next = first_dev_address(conf->reshape_progress - 1, + &conf->geo); + + /* 'safe' is the last device address that we might read from + * in the old layout after a restart + */ + safe = last_dev_address(conf->reshape_safe - 1, + &conf->prev); + + if (next + conf->offset_diff < safe) + need_flush = 1; + + last = conf->reshape_progress - 1; + sector_nr = last & ~(sector_t)(conf->geo.chunk_mask + & conf->prev.chunk_mask); + if (sector_nr + RESYNC_BLOCK_SIZE/512 < last) + sector_nr = last + 1 - RESYNC_BLOCK_SIZE/512; + } else { + /* 'next' is after the last device address that we + * might write to for this chunk in the new layout + */ + next = last_dev_address(conf->reshape_progress, &conf->geo); + + /* 'safe' is the earliest device address that we might + * read from in the old layout after a restart + */ + safe = first_dev_address(conf->reshape_safe, &conf->prev); + + /* Need to update metadata if 'next' might be beyond 'safe' + * as that would possibly corrupt data + */ + if (next > safe + conf->offset_diff) + need_flush = 1; + + sector_nr = conf->reshape_progress; + last = sector_nr | (conf->geo.chunk_mask + & conf->prev.chunk_mask); + + if (sector_nr + RESYNC_BLOCK_SIZE/512 <= last) + last = sector_nr + RESYNC_BLOCK_SIZE/512 - 1; + } + + if (need_flush || + time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) { + /* Need to update reshape_position in metadata */ + wait_barrier(conf); + mddev->reshape_position = conf->reshape_progress; + if (mddev->reshape_backwards) + mddev->curr_resync_completed = raid10_size(mddev, 0, 0) + - conf->reshape_progress; + else + mddev->curr_resync_completed = conf->reshape_progress; + conf->reshape_checkpoint = jiffies; + set_bit(MD_CHANGE_DEVS, &mddev->flags); + md_wakeup_thread(mddev->thread); + wait_event(mddev->sb_wait, mddev->flags == 0 || + kthread_should_stop()); + conf->reshape_safe = mddev->reshape_position; + allow_barrier(conf); + } + +read_more: + /* Now schedule reads for blocks from sector_nr to last */ + r10_bio = mempool_alloc(conf->r10buf_pool, GFP_NOIO); + raise_barrier(conf, sectors_done != 0); + atomic_set(&r10_bio->remaining, 0); + r10_bio->mddev = mddev; + r10_bio->sector = sector_nr; + set_bit(R10BIO_IsReshape, &r10_bio->state); + r10_bio->sectors = last - sector_nr + 1; + rdev = read_balance(conf, r10_bio, &max_sectors); + BUG_ON(!test_bit(R10BIO_Previous, &r10_bio->state)); + + if (!rdev) { + /* Cannot read from here, so need to record bad blocks + * on all the target devices. + */ + // FIXME + set_bit(MD_RECOVERY_INTR, &mddev->recovery); + return sectors_done; + } + + read_bio = bio_alloc_mddev(GFP_KERNEL, RESYNC_PAGES, mddev); + + read_bio->bi_bdev = rdev->bdev; + read_bio->bi_sector = (r10_bio->devs[r10_bio->read_slot].addr + + rdev->data_offset); + read_bio->bi_private = r10_bio; + read_bio->bi_end_io = end_sync_read; + read_bio->bi_rw = READ; + read_bio->bi_flags &= ~(BIO_POOL_MASK - 1); + read_bio->bi_flags |= 1 << BIO_UPTODATE; + read_bio->bi_vcnt = 0; + read_bio->bi_idx = 0; + read_bio->bi_size = 0; + r10_bio->master_bio = read_bio; + r10_bio->read_slot = r10_bio->devs[r10_bio->read_slot].devnum; + + /* Now find the locations in the new layout */ + __raid10_find_phys(&conf->geo, r10_bio); + + blist = read_bio; + read_bio->bi_next = NULL; + + for (s = 0; s < conf->copies*2; s++) { + struct bio *b; + int d = r10_bio->devs[s/2].devnum; + struct md_rdev *rdev2; + if (s&1) { + rdev2 = conf->mirrors[d].replacement; + b = r10_bio->devs[s/2].repl_bio; + } else { + rdev2 = conf->mirrors[d].rdev; + b = r10_bio->devs[s/2].bio; + } + if (!rdev2 || test_bit(Faulty, &rdev2->flags)) + continue; + b->bi_bdev = rdev2->bdev; + b->bi_sector = r10_bio->devs[s/2].addr + rdev2->new_data_offset; + b->bi_private = r10_bio; + b->bi_end_io = end_reshape_write; + b->bi_rw = WRITE; + b->bi_flags &= ~(BIO_POOL_MASK - 1); + b->bi_flags |= 1 << BIO_UPTODATE; + b->bi_next = blist; + b->bi_vcnt = 0; + b->bi_idx = 0; + b->bi_size = 0; + blist = b; + } + + /* Now add as many pages as possible to all of these bios. */ + + nr_sectors = 0; + for (s = 0 ; s < max_sectors; s += PAGE_SIZE >> 9) { + struct page *page = r10_bio->devs[0].bio->bi_io_vec[s/(PAGE_SIZE>>9)].bv_page; + int len = (max_sectors - s) << 9; + if (len > PAGE_SIZE) + len = PAGE_SIZE; + for (bio = blist; bio ; bio = bio->bi_next) { + struct bio *bio2; + if (bio_add_page(bio, page, len, 0)) + continue; + + /* Didn't fit, must stop */ + for (bio2 = blist; + bio2 && bio2 != bio; + bio2 = bio2->bi_next) { + /* Remove last page from this bio */ + bio2->bi_vcnt--; + bio2->bi_size -= len; + bio2->bi_flags &= ~(1<<BIO_SEG_VALID); + } + goto bio_full; + } + sector_nr += len >> 9; + nr_sectors += len >> 9; + } +bio_full: + r10_bio->sectors = nr_sectors; + + /* Now submit the read */ + md_sync_acct(read_bio->bi_bdev, r10_bio->sectors); + atomic_inc(&r10_bio->remaining); + read_bio->bi_next = NULL; + generic_make_request(read_bio); + sector_nr += nr_sectors; + sectors_done += nr_sectors; + if (sector_nr <= last) + goto read_more; + + /* Now that we have done the whole section we can + * update reshape_progress + */ + if (mddev->reshape_backwards) + conf->reshape_progress -= sectors_done; + else + conf->reshape_progress += sectors_done; + + return sectors_done; +} + +static void end_reshape_request(struct r10bio *r10_bio); +static int handle_reshape_read_error(struct mddev *mddev, + struct r10bio *r10_bio); +static void reshape_request_write(struct mddev *mddev, struct r10bio *r10_bio) +{ + /* Reshape read completed. Hopefully we have a block + * to write out. + * If we got a read error then we do sync 1-page reads from + * elsewhere until we find the data - or give up. + */ + struct r10conf *conf = mddev->private; + int s; + + if (!test_bit(R10BIO_Uptodate, &r10_bio->state)) + if (handle_reshape_read_error(mddev, r10_bio) < 0) { + /* Reshape has been aborted */ + md_done_sync(mddev, r10_bio->sectors, 0); + return; + } + + /* We definitely have the data in the pages, schedule the + * writes. + */ + atomic_set(&r10_bio->remaining, 1); + for (s = 0; s < conf->copies*2; s++) { + struct bio *b; + int d = r10_bio->devs[s/2].devnum; + struct md_rdev *rdev; + if (s&1) { + rdev = conf->mirrors[d].replacement; + b = r10_bio->devs[s/2].repl_bio; + } else { + rdev = conf->mirrors[d].rdev; + b = r10_bio->devs[s/2].bio; + } + if (!rdev || test_bit(Faulty, &rdev->flags)) + continue; + atomic_inc(&rdev->nr_pending); + md_sync_acct(b->bi_bdev, r10_bio->sectors); + atomic_inc(&r10_bio->remaining); + b->bi_next = NULL; + generic_make_request(b); + } + end_reshape_request(r10_bio); +} + +static void end_reshape(struct r10conf *conf) +{ + if (test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) + return; + + spin_lock_irq(&conf->device_lock); + conf->prev = conf->geo; + md_finish_reshape(conf->mddev); + smp_wmb(); + conf->reshape_progress = MaxSector; + spin_unlock_irq(&conf->device_lock); + + /* read-ahead size must cover two whole stripes, which is + * 2 * (datadisks) * chunksize where 'n' is the number of raid devices + */ + if (conf->mddev->queue) { + int stripe = conf->geo.raid_disks * + ((conf->mddev->chunk_sectors << 9) / PAGE_SIZE); + stripe /= conf->geo.near_copies; + if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) + conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; + } + conf->fullsync = 0; +} + + +static int handle_reshape_read_error(struct mddev *mddev, + struct r10bio *r10_bio) +{ + /* Use sync reads to get the blocks from somewhere else */ + int sectors = r10_bio->sectors; + struct r10bio r10b; + struct r10conf *conf = mddev->private; + int slot = 0; + int idx = 0; + struct bio_vec *bvec = r10_bio->master_bio->bi_io_vec; + + r10b.sector = r10_bio->sector; + __raid10_find_phys(&conf->prev, &r10b); + + while (sectors) { + int s = sectors; + int success = 0; + int first_slot = slot; + + if (s > (PAGE_SIZE >> 9)) + s = PAGE_SIZE >> 9; + + while (!success) { + int d = r10b.devs[slot].devnum; + struct md_rdev *rdev = conf->mirrors[d].rdev; + sector_t addr; + if (rdev == NULL || + test_bit(Faulty, &rdev->flags) || + !test_bit(In_sync, &rdev->flags)) + goto failed; + + addr = r10b.devs[slot].addr + idx * PAGE_SIZE; + success = sync_page_io(rdev, + addr, + s << 9, + bvec[idx].bv_page, + READ, false); + if (success) + break; + failed: + slot++; + if (slot >= conf->copies) + slot = 0; + if (slot == first_slot) + break; + } + if (!success) { + /* couldn't read this block, must give up */ + set_bit(MD_RECOVERY_INTR, + &mddev->recovery); + return -EIO; + } + sectors -= s; + idx++; + } + return 0; +} + +static void end_reshape_write(struct bio *bio, int error) +{ + int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); + struct r10bio *r10_bio = bio->bi_private; + struct mddev *mddev = r10_bio->mddev; + struct r10conf *conf = mddev->private; + int d; + int slot; + int repl; + struct md_rdev *rdev = NULL; + + d = find_bio_disk(conf, r10_bio, bio, &slot, &repl); + if (repl) + rdev = conf->mirrors[d].replacement; + if (!rdev) { + smp_mb(); + rdev = conf->mirrors[d].rdev; + } + + if (!uptodate) { + /* FIXME should record badblock */ + md_error(mddev, rdev); + } + + rdev_dec_pending(rdev, mddev); + end_reshape_request(r10_bio); +} + +static void end_reshape_request(struct r10bio *r10_bio) +{ + if (!atomic_dec_and_test(&r10_bio->remaining)) + return; + md_done_sync(r10_bio->mddev, r10_bio->sectors, 1); + bio_put(r10_bio->master_bio); + put_buf(r10_bio); +} + +static void raid10_finish_reshape(struct mddev *mddev) +{ + struct r10conf *conf = mddev->private; + + if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) + return; + + if (mddev->delta_disks > 0) { + sector_t size = raid10_size(mddev, 0, 0); + md_set_array_sectors(mddev, size); + if (mddev->recovery_cp > mddev->resync_max_sectors) { + mddev->recovery_cp = mddev->resync_max_sectors; + set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); + } + mddev->resync_max_sectors = size; + set_capacity(mddev->gendisk, mddev->array_sectors); + revalidate_disk(mddev->gendisk); + } + mddev->layout = mddev->new_layout; + mddev->chunk_sectors = 1 << conf->geo.chunk_shift; + mddev->reshape_position = MaxSector; + mddev->delta_disks = 0; + mddev->reshape_backwards = 0; +} + static struct md_personality raid10_personality = { .name = "raid10", @@ -3652,6 +4493,9 @@ static struct md_personality raid10_personality = .size = raid10_size, .resize = raid10_resize, .takeover = raid10_takeover, + .check_reshape = raid10_check_reshape, + .start_reshape = raid10_start_reshape, + .finish_reshape = raid10_finish_reshape, }; static int __init raid_init(void) |