From dab8b29248b3f14f456651a2a6ee9b8fd16d1b3c Mon Sep 17 00:00:00 2001 From: "Trela, Maciej" Date: Mon, 8 Mar 2010 16:02:45 +1100 Subject: md: Add support for Raid0->Raid10 takeover Signed-off-by: Maciej Trela Signed-off-by: NeilBrown --- drivers/md/raid10.c | 194 ++++++++++++++++++++++++++++++++++++++-------------- drivers/md/raid10.h | 12 ++++ 2 files changed, 155 insertions(+), 51 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 044c1157d98d..57d71d5d88f4 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -23,6 +23,7 @@ #include #include "md.h" #include "raid10.h" +#include "raid0.h" #include "bitmap.h" /* @@ -2141,7 +2142,7 @@ raid10_size(mddev_t *mddev, sector_t sectors, int raid_disks) if (!raid_disks) raid_disks = conf->raid_disks; if (!sectors) - sectors = mddev->dev_sectors; + sectors = conf->dev_sectors; size = sectors >> conf->chunk_shift; sector_div(size, conf->far_copies); @@ -2151,62 +2152,60 @@ raid10_size(mddev_t *mddev, sector_t sectors, int raid_disks) return size << conf->chunk_shift; } -static int run(mddev_t *mddev) + +static conf_t *setup_conf(mddev_t *mddev) { - conf_t *conf; - int i, disk_idx, chunk_size; - mirror_info_t *disk; - mdk_rdev_t *rdev; + conf_t *conf = NULL; int nc, fc, fo; sector_t stride, size; + int err = -EINVAL; if (mddev->chunk_sectors < (PAGE_SIZE >> 9) || !is_power_of_2(mddev->chunk_sectors)) { printk(KERN_ERR "md/raid10: chunk size must be " "at least PAGE_SIZE(%ld) and be a power of 2.\n", PAGE_SIZE); - return -EINVAL; + goto out; } nc = mddev->layout & 255; fc = (mddev->layout >> 8) & 255; fo = mddev->layout & (1<<16); + if ((nc*fc) <2 || (nc*fc) > mddev->raid_disks || (mddev->layout >> 17)) { printk(KERN_ERR "raid10: %s: unsupported raid10 layout: 0x%8x\n", mdname(mddev), mddev->layout); goto out; } - /* - * copy the already verified devices into our private RAID10 - * bookkeeping area. [whatever we allocate in run(), - * should be freed in stop()] - */ + + err = -ENOMEM; conf = kzalloc(sizeof(conf_t), GFP_KERNEL); - mddev->private = conf; - if (!conf) { - printk(KERN_ERR "raid10: couldn't allocate memory for %s\n", - mdname(mddev)); + if (!conf) goto out; - } + conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks, - GFP_KERNEL); - if (!conf->mirrors) { - printk(KERN_ERR "raid10: couldn't allocate memory for %s\n", - mdname(mddev)); - goto out_free_conf; - } + GFP_KERNEL); + if (!conf->mirrors) + goto out; conf->tmppage = alloc_page(GFP_KERNEL); if (!conf->tmppage) - goto out_free_conf; + goto out; + conf->raid_disks = mddev->raid_disks; conf->near_copies = nc; conf->far_copies = fc; conf->copies = nc*fc; conf->far_offset = fo; - conf->chunk_mask = mddev->chunk_sectors - 1; - conf->chunk_shift = ffz(~mddev->chunk_sectors); + conf->chunk_mask = mddev->new_chunk_sectors - 1; + conf->chunk_shift = ffz(~mddev->new_chunk_sectors); + + conf->r10bio_pool = mempool_create(NR_RAID10_BIOS, r10bio_pool_alloc, + r10bio_pool_free, conf); + if (!conf->r10bio_pool) + goto out; + size = mddev->dev_sectors >> conf->chunk_shift; sector_div(size, fc); size = size * conf->raid_disks; @@ -2220,7 +2219,8 @@ static int run(mddev_t *mddev) */ stride += conf->raid_disks - 1; sector_div(stride, conf->raid_disks); - mddev->dev_sectors = stride << conf->chunk_shift; + + conf->dev_sectors = stride << conf->chunk_shift; if (fo) stride = 1; @@ -2228,18 +2228,63 @@ static int run(mddev_t *mddev) sector_div(stride, fc); conf->stride = stride << conf->chunk_shift; - conf->r10bio_pool = mempool_create(NR_RAID10_BIOS, r10bio_pool_alloc, - r10bio_pool_free, conf); - if (!conf->r10bio_pool) { - printk(KERN_ERR "raid10: couldn't allocate memory for %s\n", - mdname(mddev)); - goto out_free_conf; - } - conf->mddev = mddev; spin_lock_init(&conf->device_lock); + INIT_LIST_HEAD(&conf->retry_list); + + spin_lock_init(&conf->resync_lock); + init_waitqueue_head(&conf->wait_barrier); + + conf->thread = md_register_thread(raid10d, mddev, NULL); + if (!conf->thread) + goto out; + + conf->scale_disks = 0; + conf->mddev = mddev; + return conf; + + out: + printk(KERN_ERR "raid10: couldn't allocate memory for %s\n", + mdname(mddev)); + if (conf) { + if (conf->r10bio_pool) + mempool_destroy(conf->r10bio_pool); + kfree(conf->mirrors); + safe_put_page(conf->tmppage); + kfree(conf); + } + return ERR_PTR(err); +} + +static int run(mddev_t *mddev) +{ + conf_t *conf; + int i, disk_idx, chunk_size; + mirror_info_t *disk; + mdk_rdev_t *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()] + */ + + if (mddev->private == NULL) { + conf = setup_conf(mddev); + if (IS_ERR(conf)) + return PTR_ERR(conf); + mddev->private = conf; + } + conf = mddev->private; + if (!conf) + goto out; + mddev->queue->queue_lock = &conf->device_lock; + mddev->thread = conf->thread; + conf->thread = NULL; + chunk_size = mddev->chunk_sectors << 9; blk_queue_io_min(mddev->queue, chunk_size); if (conf->raid_disks % conf->near_copies) @@ -2253,6 +2298,11 @@ static int run(mddev_t *mddev) if (disk_idx >= conf->raid_disks || disk_idx < 0) continue; + if (conf->scale_disks) { + disk_idx *= conf->scale_disks; + rdev->raid_disk = disk_idx; + /* MOVE 'rd%d' link !! */ + } disk = conf->mirrors + disk_idx; disk->rdev = rdev; @@ -2270,11 +2320,6 @@ static int run(mddev_t *mddev) disk->head_position = 0; } - INIT_LIST_HEAD(&conf->retry_list); - - spin_lock_init(&conf->resync_lock); - init_waitqueue_head(&conf->wait_barrier); - /* need to check that every block has at least one working mirror */ if (!enough(conf)) { printk(KERN_ERR "raid10: not enough operational mirrors for %s\n", @@ -2296,15 +2341,6 @@ static int run(mddev_t *mddev) } } - - mddev->thread = md_register_thread(raid10d, mddev, NULL); - if (!mddev->thread) { - printk(KERN_ERR - "raid10: couldn't allocate thread for %s\n", - mdname(mddev)); - goto out_free_conf; - } - if (mddev->recovery_cp != MaxSector) printk(KERN_NOTICE "raid10: %s is not clean" " -- starting background reconstruction\n", @@ -2316,8 +2352,10 @@ static int run(mddev_t *mddev) /* * Ok, everything is just fine now */ - md_set_array_sectors(mddev, raid10_size(mddev, 0, 0)); - mddev->resync_max_sectors = raid10_size(mddev, 0, 0); + mddev->dev_sectors = conf->dev_sectors; + size = raid10_size(mddev, 0, 0); + md_set_array_sectors(mddev, size); + mddev->resync_max_sectors = size; mddev->queue->unplug_fn = raid10_unplug; mddev->queue->backing_dev_info.congested_fn = raid10_congested; @@ -2347,6 +2385,7 @@ out_free_conf: kfree(conf->mirrors); kfree(conf); mddev->private = NULL; + md_unregister_thread(mddev->thread); out: return -EIO; } @@ -2383,6 +2422,58 @@ static void raid10_quiesce(mddev_t *mddev, int state) } } +static void *raid10_takeover_raid0(mddev_t *mddev) +{ + mdk_rdev_t *rdev; + conf_t *conf; + + if (mddev->degraded > 0) { + printk(KERN_ERR "error: degraded raid0!\n"); + return ERR_PTR(-EINVAL); + } + + /* Update slot numbers to obtain + * degraded raid10 with missing mirrors + */ + list_for_each_entry(rdev, &mddev->disks, same_set) { + rdev->raid_disk *= 2; + } + + /* Set new parameters */ + mddev->new_level = 10; + /* new layout: far_copies = 1, near_copies = 2 */ + mddev->new_layout = (1<<8) + 2; + mddev->new_chunk_sectors = mddev->chunk_sectors; + mddev->delta_disks = mddev->raid_disks; + mddev->degraded = mddev->raid_disks; + mddev->raid_disks *= 2; + /* make sure it will be not marked as dirty */ + mddev->recovery_cp = MaxSector; + + conf = setup_conf(mddev); + conf->scale_disks = 2; + return conf; +} + +static void *raid10_takeover(mddev_t *mddev) +{ + struct raid0_private_data *raid0_priv; + + /* raid10 can take over: + * raid0 - providing it has only two drives + */ + if (mddev->level == 0) { + /* for raid0 takeover only one zone is supported */ + raid0_priv = mddev->private; + if (raid0_priv->nr_strip_zones > 1) { + printk(KERN_ERR "md: cannot takeover raid 0 with more than one zone.\n"); + return ERR_PTR(-EINVAL); + } + return raid10_takeover_raid0(mddev); + } + return ERR_PTR(-EINVAL); +} + static struct mdk_personality raid10_personality = { .name = "raid10", @@ -2399,6 +2490,7 @@ static struct mdk_personality raid10_personality = .sync_request = sync_request, .quiesce = raid10_quiesce, .size = raid10_size, + .takeover = raid10_takeover, }; static int __init raid_init(void) diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h index 59cd1efb8d30..3824a087e17c 100644 --- a/drivers/md/raid10.h +++ b/drivers/md/raid10.h @@ -33,9 +33,16 @@ struct r10_private_data_s { * 1 stripe. */ + sector_t dev_sectors; /* temp copy of mddev->dev_sectors */ + int chunk_shift; /* shift from chunks to sectors */ sector_t chunk_mask; + int scale_disks; /* When starting array, multiply + * each ->raid_disk by this. + * Need for raid0->raid10 migration + */ + struct list_head retry_list; /* queue pending writes and submit them on unplug */ struct bio_list pending_bio_list; @@ -57,6 +64,11 @@ struct r10_private_data_s { mempool_t *r10bio_pool; mempool_t *r10buf_pool; struct page *tmppage; + + /* When taking over an array from a different personality, we store + * the new thread here until we fully activate the array. + */ + struct mdk_thread_s *thread; }; typedef struct r10_private_data_s conf_t; -- cgit v1.2.3