From 88ce4930e2b80378d45506ce2c3bb5820e156e85 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 31 Mar 2009 15:24:23 +1100 Subject: md/raid5: allow layout and chunksize to be changed on active array. If an array has 3 or more devices, we allow the chunksize or layout to be changed and when a reshape starts, we use these as the 'new' values. Signed-off-by: NeilBrown --- drivers/md/raid5.c | 76 ++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 56 insertions(+), 20 deletions(-) (limited to 'drivers') diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index f7fb2b87ad89..4fdc6d02b447 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -4397,9 +4397,7 @@ static int run(mddev_t *mddev) int old_disks; int max_degraded = (mddev->level == 6 ? 2 : 1); - if (mddev->new_level != mddev->level || - mddev->new_layout != mddev->layout || - mddev->new_chunk != mddev->chunk_size) { + if (mddev->new_level != mddev->level) { printk(KERN_ERR "raid5: %s: unsupported reshape " "required - aborting.\n", mdname(mddev)); @@ -4784,8 +4782,10 @@ static int raid5_check_reshape(mddev_t *mddev) { raid5_conf_t *conf = mddev_to_conf(mddev); - if (mddev->delta_disks == 0) - return 0; /* nothing to do */ + if (mddev->delta_disks == 0 && + mddev->new_layout == mddev->layout && + mddev->new_chunk == mddev->chunk_size) + return -EINVAL; /* nothing to do */ if (mddev->bitmap) /* Cannot grow a bitmap yet */ return -EBUSY; @@ -4860,6 +4860,10 @@ static int raid5_start_reshape(mddev_t *mddev) spin_lock_irq(&conf->device_lock); conf->previous_raid_disks = conf->raid_disks; conf->raid_disks += mddev->delta_disks; + conf->prev_chunk = conf->chunk_size; + conf->chunk_size = mddev->new_chunk; + conf->prev_algo = conf->algorithm; + conf->algorithm = mddev->new_layout; if (mddev->delta_disks < 0) conf->reshape_progress = raid5_size(mddev, 0, 0); else @@ -4952,6 +4956,7 @@ static void end_reshape(raid5_conf_t *conf) static void raid5_finish_reshape(mddev_t *mddev) { struct block_device *bdev; + raid5_conf_t *conf = mddev_to_conf(mddev); if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) { @@ -4970,7 +4975,6 @@ static void raid5_finish_reshape(mddev_t *mddev) } } else { int d; - raid5_conf_t *conf = mddev_to_conf(mddev); mddev->degraded = conf->raid_disks; for (d = 0; d < conf->raid_disks ; d++) if (conf->disks[d].rdev && @@ -4982,6 +4986,8 @@ static void raid5_finish_reshape(mddev_t *mddev) d++) raid5_remove_disk(mddev, d); } + mddev->layout = conf->algorithm; + mddev->chunk_size = conf->chunk_size; mddev->reshape_position = MaxSector; mddev->delta_disks = 0; } @@ -5080,11 +5086,10 @@ static void *raid5_takeover_raid6(mddev_t *mddev) static int raid5_reconfig(mddev_t *mddev, int new_layout, int new_chunk) { - /* Currently the layout and chunk size can only be changed - * for a 2-drive raid array, as in that case no data shuffling - * is required. - * Later we might validate these and set new_* so a reshape - * can complete the change. + /* For a 2-drive array, the layout and chunk size can be changed + * immediately as not restriping is needed. + * For larger arrays we record the new value - after validation + * to be used by a reshape pass. */ raid5_conf_t *conf = mddev_to_conf(mddev); @@ -5103,19 +5108,49 @@ static int raid5_reconfig(mddev_t *mddev, int new_layout, int new_chunk) /* They look valid */ - if (mddev->raid_disks != 2) - return -EINVAL; + if (mddev->raid_disks == 2) { - if (new_layout >= 0) { - conf->algorithm = new_layout; - mddev->layout = mddev->new_layout = new_layout; + if (new_layout >= 0) { + conf->algorithm = new_layout; + mddev->layout = mddev->new_layout = new_layout; + } + if (new_chunk > 0) { + conf->chunk_size = new_chunk; + mddev->chunk_size = mddev->new_chunk = new_chunk; + } + set_bit(MD_CHANGE_DEVS, &mddev->flags); + md_wakeup_thread(mddev->thread); + } else { + if (new_layout >= 0) + mddev->new_layout = new_layout; + if (new_chunk > 0) + mddev->new_chunk = new_chunk; } + return 0; +} + +static int raid6_reconfig(mddev_t *mddev, int new_layout, int new_chunk) +{ + if (new_layout >= 0 && !algorithm_valid_raid6(new_layout)) + return -EINVAL; if (new_chunk > 0) { - conf->chunk_size = new_chunk; - mddev->chunk_size = mddev->new_chunk = new_chunk; + if (new_chunk & (new_chunk-1)) + /* not a power of 2 */ + return -EINVAL; + if (new_chunk < PAGE_SIZE) + return -EINVAL; + if (mddev->array_sectors & ((new_chunk>>9)-1)) + /* not factor of array size */ + return -EINVAL; } - set_bit(MD_CHANGE_DEVS, &mddev->flags); - md_wakeup_thread(mddev->thread); + + /* They look valid */ + + if (new_layout >= 0) + mddev->new_layout = new_layout; + if (new_chunk > 0) + mddev->new_chunk = new_chunk; + return 0; } @@ -5216,6 +5251,7 @@ static struct mdk_personality raid6_personality = #endif .quiesce = raid5_quiesce, .takeover = raid6_takeover, + .reconfig = raid6_reconfig, }; static struct mdk_personality raid5_personality = { -- cgit v1.2.3