A 2-device raid5 array can now be converted to raid1.
Signed-off-by: NeilBrown <neilb@xxxxxxx>
---
drivers/md/raid1.c | 193 +++++++++++++++++++++++++++++++---------------------
drivers/md/raid1.h | 5 +
2 files changed, 121 insertions(+), 77 deletions(-)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 35b2d86..18da334 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -677,6 +677,7 @@ static void raise_barrier(conf_t *conf)
static void lower_barrier(conf_t *conf)
{
unsigned long flags;
+ BUG_ON(conf->barrier <= 0);
spin_lock_irqsave(&conf->resync_lock, flags);
conf->barrier--;
spin_unlock_irqrestore(&conf->resync_lock, flags);
@@ -1960,74 +1961,48 @@ static sector_t raid1_size(mddev_t *mddev, sector_t sectors, int raid_disks)
return mddev->dev_sectors;
}
-static int run(mddev_t *mddev)
+static conf_t *setup_conf(mddev_t *mddev)
{
conf_t *conf;
- int i, j, disk_idx;
- mirror_info_t *disk;
mdk_rdev_t *rdev;
+ int err = -ENOMEM;
+ mirror_info_t *disk;
+ int i;
- if (mddev->level != 1) {
- printk("raid1: %s: raid level not set to mirroring (%d)\n",
- mdname(mddev), mddev->level);
- goto out;
- }
- if (mddev->reshape_position != MaxSector) {
- printk("raid1: %s: reshape_position set but not supported\n",
- mdname(mddev));
- goto out;
- }
- /*
- * copy the already verified devices into our private RAID1
- * bookkeeping area. [whatever we allocate in run(),
- * should be freed in stop()]
- */
conf = kzalloc(sizeof(conf_t), GFP_KERNEL);
- mddev->private = conf;
if (!conf)
- goto out_no_mem;
+ goto abort;
conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks,
GFP_KERNEL);
if (!conf->mirrors)
- goto out_no_mem;
+ goto abort;
conf->tmppage = alloc_page(GFP_KERNEL);
if (!conf->tmppage)
- goto out_no_mem;
+ goto abort;
- conf->poolinfo = kmalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
+ conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
if (!conf->poolinfo)
- goto out_no_mem;
- conf->poolinfo->mddev = NULL;
+ goto abort;
conf->poolinfo->raid_disks = mddev->raid_disks;
conf->r1bio_pool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc,
r1bio_pool_free,
conf->poolinfo);
if (!conf->r1bio_pool)
- goto out_no_mem;
+ goto abort;
+
conf->poolinfo->mddev = mddev;
spin_lock_init(&conf->device_lock);
- mddev->queue->queue_lock = &conf->device_lock;
-
list_for_each_entry(rdev, &mddev->disks, same_set) {
- disk_idx = rdev->raid_disk;
+ int disk_idx = rdev->raid_disk;
if (disk_idx >= mddev->raid_disks
|| disk_idx < 0)
continue;
disk = conf->mirrors + disk_idx;
disk->rdev = rdev;
- disk_stack_limits(mddev->gendisk, rdev->bdev,
- rdev->data_offset << 9);
- /* as we don't honour merge_bvec_fn, we must never risk
- * violating it, so limit ->max_sector to one PAGE, as
- * a one page request is never in violation.
- */
- if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
- queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
- blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
disk->head_position = 0;
}
@@ -2041,8 +2016,7 @@ static int run(mddev_t *mddev)
bio_list_init(&conf->pending_bio_list);
bio_list_init(&conf->flushing_bio_list);
-
- mddev->degraded = 0;
+ conf->last_used = -1;
for (i = 0; i < conf->raid_disks; i++) {
disk = conf->mirrors + i;
@@ -2050,38 +2024,97 @@ static int run(mddev_t *mddev)
if (!disk->rdev ||
!test_bit(In_sync, &disk->rdev->flags)) {
disk->head_position = 0;
- mddev->degraded++;
if (disk->rdev)
conf->fullsync = 1;
- }
+ } else if (conf->last_used < 0)
+ /*
+ * The first working device is used as a
+ * starting point to read balancing.
+ */
+ conf->last_used = i;
}
- if (mddev->degraded == conf->raid_disks) {
+
+ err = -EIO;
+ if (conf->last_used < 0) {
printk(KERN_ERR "raid1: no operational mirrors for %s\n",
- mdname(mddev));
- goto out_free_conf;
+ mdname(mddev));
+ goto abort;
}
- if (conf->raid_disks - mddev->degraded == 1)
- mddev->recovery_cp = MaxSector;
+ err = -ENOMEM;
+ conf->thread = md_register_thread(raid1d, mddev, NULL);
+ if (!conf->thread) {
+ printk(KERN_ERR
+ "raid1: couldn't allocate thread for %s\n",
+ mdname(mddev));
+ goto abort;
+ }
+
+ return conf;
+
+ abort:
+ if (conf) {
+ if (conf->r1bio_pool)
+ mempool_destroy(conf->r1bio_pool);
+ kfree(conf->mirrors);
+ safe_put_page(conf->tmppage);
+ kfree(conf->poolinfo);
+ kfree(conf);
+ }
+ return ERR_PTR(err);
+}
+static int run(mddev_t *mddev)
+{
+ conf_t *conf;
+ int i;
+ mdk_rdev_t *rdev;
+
+ if (mddev->level != 1) {
+ printk("raid1: %s: raid level not set to mirroring (%d)\n",
+ mdname(mddev), mddev->level);
+ return -EIO;
+ }
+ if (mddev->reshape_position != MaxSector) {
+ printk("raid1: %s: reshape_position set but not supported\n",
+ mdname(mddev));
+ return -EIO;
+ }
/*
- * find the first working one and use it as a starting point
- * to read balancing.
+ * copy the already verified devices into our private RAID1
+ * bookkeeping area. [whatever we allocate in run(),
+ * should be freed in stop()]
*/
- for (j = 0; j < conf->raid_disks &&
- (!conf->mirrors[j].rdev ||
- !test_bit(In_sync, &conf->mirrors[j].rdev->flags)) ; j++)
- /* nothing */;
- conf->last_used = j;
+ if (mddev->private == NULL)
+ conf = setup_conf(mddev);
+ else
+ conf = mddev->private;
+ if (IS_ERR(conf))
+ return PTR_ERR(conf);
- mddev->thread = md_register_thread(raid1d, mddev, NULL);
- if (!mddev->thread) {
- printk(KERN_ERR
- "raid1: couldn't allocate thread for %s\n",
- mdname(mddev));
- goto out_free_conf;
+ mddev->queue->queue_lock = &conf->device_lock;
+ list_for_each_entry(rdev, &mddev->disks, same_set) {
+ disk_stack_limits(mddev->gendisk, rdev->bdev,
+ rdev->data_offset << 9);
+ /* as we don't honour merge_bvec_fn, we must never risk
+ * violating it, so limit ->max_sector to one PAGE, as
+ * a one page request is never in violation.
+ */
+ if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
+ queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
+ blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
}
+ mddev->degraded = 0;
+ for (i=0; i < conf->raid_disks; i++)
+ if (conf->mirrors[i].rdev == NULL ||
+ !test_bit(In_sync, &conf->mirrors[i].rdev->flags) ||
+ test_bit(Faulty, &conf->mirrors[i].rdev->flags))
+ mddev->degraded++;
+
+ if (conf->raid_disks - mddev->degraded == 1)
+ mddev->recovery_cp = MaxSector;
+
if (mddev->recovery_cp != MaxSector)
printk(KERN_NOTICE "raid1: %s is not clean"
" -- starting background reconstruction\n",
@@ -2090,9 +2123,14 @@ static int run(mddev_t *mddev)
"raid1: raid set %s active with %d out of %d mirrors\n",
mdname(mddev), mddev->raid_disks - mddev->degraded,
mddev->raid_disks);
+
/*
* Ok, everything is just fine now
*/
+ mddev->thread = conf->thread;
+ conf->thread = NULL;
+ mddev->private = conf;
+
md_set_array_sectors(mddev, raid1_size(mddev, 0, 0));
mddev->queue->unplug_fn = raid1_unplug;
@@ -2100,23 +2138,6 @@ static int run(mddev_t *mddev)
mddev->queue->backing_dev_info.congested_data = mddev;
md_integrity_register(mddev);
return 0;
-
-out_no_mem:
- printk(KERN_ERR "raid1: couldn't allocate memory for %s\n",
- mdname(mddev));
-
-out_free_conf:
- if (conf) {
- if (conf->r1bio_pool)
- mempool_destroy(conf->r1bio_pool);
- kfree(conf->mirrors);
- safe_put_page(conf->tmppage);
- kfree(conf->poolinfo);
- kfree(conf);
- mddev->private = NULL;
- }
-out:
- return -EIO;
}
static int stop(mddev_t *mddev)
@@ -2302,6 +2323,23 @@ static void raid1_quiesce(mddev_t *mddev, int state)
}
}
+static void *raid1_takeover(mddev_t *mddev)
+{
+ /* raid1 can take over:
+ * raid5 with 2 devices, any layout or chunk size
+ */
+ if (mddev->level == 5 && mddev->raid_disks == 2) {
+ conf_t *conf;
+ mddev->new_level = 1;
+ mddev->new_layout = 0;
+ mddev->new_chunk_sectors = 0;
+ conf = setup_conf(mddev);
+ if (!IS_ERR(conf))
+ conf->barrier = 1;
+ return conf;
+ }
+ return ERR_PTR(-EINVAL);
+}
static struct mdk_personality raid1_personality =
{
@@ -2321,6 +2359,7 @@ static struct mdk_personality raid1_personality =
.size = raid1_size,
.check_reshape = raid1_reshape,
.quiesce = raid1_quiesce,
+ .takeover = raid1_takeover,
};
static int __init raid_init(void)
diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h
index e87b84d..5f2d443 100644
--- a/drivers/md/raid1.h
+++ b/drivers/md/raid1.h
@@ -59,6 +59,11 @@ struct r1_private_data_s {
mempool_t *r1bio_pool;
mempool_t *r1buf_pool;
+
+ /* 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 r1_private_data_s conf_t;
--
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