From 9af204cf720cedf369cf823bbd806c350201f7ea Mon Sep 17 00:00:00 2001 From: "Trela, Maciej" Date: Mon, 8 Mar 2010 16:02:44 +1100 Subject: md: Add support for Raid5->Raid0 and Raid10->Raid0 takeover Signed-off-by: Maciej Trela Signed-off-by: NeilBrown --- drivers/md/raid0.c | 125 ++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 119 insertions(+), 6 deletions(-) (limited to 'drivers/md/raid0.c') diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index c2e0d1d..afddf62 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -22,6 +22,7 @@ #include #include "md.h" #include "raid0.h" +#include "raid5.h" static void raid0_unplug(struct request_queue *q) { @@ -90,7 +91,7 @@ static void dump_zones(mddev_t *mddev) printk(KERN_INFO "**********************************\n\n"); } -static int create_strip_zones(mddev_t *mddev) +static int create_strip_zones(mddev_t *mddev, raid0_conf_t **private_conf) { int i, c, err; sector_t curr_zone_end, sectors; @@ -164,6 +165,10 @@ static int create_strip_zones(mddev_t *mddev) list_for_each_entry(rdev1, &mddev->disks, same_set) { int j = rdev1->raid_disk; + if (mddev->level == 10) + /* taking over a raid10-n2 array */ + j /= 2; + if (j < 0 || j >= mddev->raid_disks) { printk(KERN_ERR "raid0: bad disk number %d - " "aborting!\n", j); @@ -264,13 +269,14 @@ static int create_strip_zones(mddev_t *mddev) (mddev->chunk_sectors << 9) * mddev->raid_disks); printk(KERN_INFO "raid0: done.\n"); - mddev->private = conf; + *private_conf = conf; + return 0; abort: kfree(conf->strip_zone); kfree(conf->devlist); kfree(conf); - mddev->private = NULL; + *private_conf = NULL; return err; } @@ -321,6 +327,7 @@ static sector_t raid0_size(mddev_t *mddev, sector_t sectors, int raid_disks) static int raid0_run(mddev_t *mddev) { + raid0_conf_t *conf; int ret; if (mddev->chunk_sectors == 0) { @@ -332,9 +339,20 @@ static int raid0_run(mddev_t *mddev) blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors); mddev->queue->queue_lock = &mddev->queue->__queue_lock; - ret = create_strip_zones(mddev); - if (ret < 0) - return ret; + /* if private is not null, we are here after takeover */ + if (mddev->private == NULL) { + ret = create_strip_zones(mddev, &conf); + if (ret < 0) + return ret; + mddev->private = conf; + } + conf = mddev->private; + if (conf->scale_raid_disks) { + int i; + for (i=0; i < conf->strip_zone[0].nb_dev; i++) + conf->devlist[i]->raid_disk /= conf->scale_raid_disks; + /* FIXME update sysfs rd links */ + } /* calculate array device size */ md_set_array_sectors(mddev, raid0_size(mddev, 0, 0)); @@ -548,6 +566,99 @@ static void raid0_status(struct seq_file *seq, mddev_t *mddev) return; } +static void *raid0_takeover_raid5(mddev_t *mddev) +{ + mdk_rdev_t *rdev; + raid0_conf_t *priv_conf; + + if (mddev->degraded != 1) { + printk(KERN_ERR "md: raid5 must be degraded! Degraded disks: %d\n", + mddev->degraded); + return ERR_PTR(-EINVAL); + } + + list_for_each_entry(rdev, &mddev->disks, same_set) { + /* check slot number for a disk */ + if (rdev->raid_disk == mddev->raid_disks-1) { + printk(KERN_ERR "md: raid5 must have missing parity disk!\n"); + return ERR_PTR(-EINVAL); + } + } + + /* Set new parameters */ + mddev->new_level = 0; + mddev->new_chunk_sectors = mddev->chunk_sectors; + mddev->raid_disks--; + mddev->delta_disks = -1; + /* make sure it will be not marked as dirty */ + mddev->recovery_cp = MaxSector; + + create_strip_zones(mddev, &priv_conf); + return priv_conf; +} + +static void *raid0_takeover_raid10(mddev_t *mddev) +{ + raid0_conf_t *priv_conf; + + /* Check layout: + * - far_copies must be 1 + * - near_copies must be 2 + * - disks number must be even + * - all mirrors must be already degraded + */ + if (mddev->layout != ((1 << 8) + 2)) { + printk(KERN_ERR "md: Raid0 cannot takover layout: %x\n", + mddev->layout); + return ERR_PTR(-EINVAL); + } + if (mddev->raid_disks & 1) { + printk(KERN_ERR "md: Raid0 cannot takover Raid10 with odd disk number.\n"); + return ERR_PTR(-EINVAL); + } + if (mddev->degraded != (mddev->raid_disks>>1)) { + printk(KERN_ERR "md: All mirrors must be already degraded!\n"); + return ERR_PTR(-EINVAL); + } + + /* Set new parameters */ + mddev->new_level = 0; + mddev->new_chunk_sectors = mddev->chunk_sectors; + mddev->delta_disks = - mddev->raid_disks / 2; + mddev->raid_disks += mddev->delta_disks; + mddev->degraded = 0; + /* make sure it will be not marked as dirty */ + mddev->recovery_cp = MaxSector; + + create_strip_zones(mddev, &priv_conf); + priv_conf->scale_raid_disks = 2; + return priv_conf; +} + +static void *raid0_takeover(mddev_t *mddev) +{ + /* raid0 can take over: + * raid5 - providing it is Raid4 layout and one disk is faulty + * raid10 - assuming we have all necessary active disks + */ + if (mddev->level == 5) { + if (mddev->layout == ALGORITHM_PARITY_N) + return raid0_takeover_raid5(mddev); + + printk(KERN_ERR "md: Raid can only takeover Raid5 with layout: %d\n", + ALGORITHM_PARITY_N); + } + + if (mddev->level == 10) + return raid0_takeover_raid10(mddev); + + return ERR_PTR(-EINVAL); +} + +static void raid0_quiesce(mddev_t *mddev, int state) +{ +} + static struct mdk_personality raid0_personality= { .name = "raid0", @@ -558,6 +669,8 @@ static struct mdk_personality raid0_personality= .stop = raid0_stop, .status = raid0_status, .size = raid0_size, + .takeover = raid0_takeover, + .quiesce = raid0_quiesce, }; static int __init raid0_init (void) -- cgit v1.1