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authorTrela, Maciej <Maciej.Trela@intel.com>2010-03-08 16:02:45 +1100
committerNeilBrown <neilb@suse.de>2010-05-18 15:27:48 +1000
commitdab8b29248b3f14f456651a2a6ee9b8fd16d1b3c (patch)
treeced1c7cd74f2e0efc5a48819aa4711047960e2d5 /drivers/md
parent9af204cf720cedf369cf823bbd806c350201f7ea (diff)
md: Add support for Raid0->Raid10 takeover
Signed-off-by: Maciej Trela <maciej.trela@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'drivers/md')
-rw-r--r--drivers/md/raid10.c194
-rw-r--r--drivers/md/raid10.h12
2 files changed, 155 insertions, 51 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 044c1157d98..57d71d5d88f 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -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)
diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h
index 59cd1efb8d3..3824a087e17 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;