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 <neilb@xxxxxxx>
---
drivers/md/raid5.c | 76 ++++++++++++++++++++++++++++++++++++++--------------
1 files changed, 56 insertions(+), 20 deletions(-)
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index f7fb2b8..4fdc6d0 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 =
{
--
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