md: Add support for Raid0->Raid10 takeover

Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
Trela, Maciej 2010-03-08 16:02:45 +11:00 committed by NeilBrown
parent 9af204cf72
commit dab8b29248
2 changed files with 155 additions and 51 deletions

View File

@ -23,6 +23,7 @@
#include <linux/seq_file.h>
#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)

View File

@ -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;