----- Original Message ----- > From: "Guoqing Jiang" <gqjiang@xxxxxxxx> > To: "Xiao Ni" <xni@xxxxxxxxxx>, linux-raid@xxxxxxxxxxxxxxx > Cc: ncroxon@xxxxxxxxxx, tbskyd@xxxxxxxxx, shli@xxxxxxxxxx > Sent: Wednesday, July 5, 2017 4:51:59 PM > Subject: Re: [MD PATCH 1/1] Raid5 should update rdev->sectors after reshape > > > > On 07/04/2017 02:29 PM, Xiao Ni wrote: > > The raid5 md device is created by the disks which we don't use the total > > size. For example, > > the size of the device is 5G and it just uses 3G of the devices to create > > one raid5 device. > > Then change the chunksize and wait reshape to finish. After reshape > > finishing stop the raid > > and assemble it again. It fails. > > mdadm -CR /dev/md0 -l5 -n3 /dev/loop[0-2] --size=3G --chunk=32 > > --assume-clean > > mdadm /dev/md0 --grow --chunk=64 > > wait reshape to finish > > mdadm -S /dev/md0 > > mdadm -As > > The error messages: > > [197519.814302] md: loop1 does not have a valid v1.2 superblock, not > > importing! > > [197519.821686] md: md_import_device returned -22 > > > > After reshape the data offset is changed. It selects backwards direction in > > this condition. > > In function super_1_load it compares the available space of the underlying > > device with > > sb->data_size. The new data offset gets bigger after reshape. So > > super_1_load returns -EINVAL. > > sb->data_size is updated in md_finish_reshape. So add md_finish_reshape in > > end_reshape. > > IMO, md_finish_reshape doesn't update sb->data_size directly, but it > updates rdev->sectors, > then super_1_sync sets sb->data_size based on rdev->sectors. Ah yes, thanks for pointing this. It should be rdev->sectors is updated in md_finish_reshape. Regards Xiao > > Acked-by: Guoqing Jiang <gqjiang@xxxxxxxx> > > Thanks, > Guoqing > > > Signed-off-by: Xiao Ni <xni@xxxxxxxxxx> > > --- > > drivers/md/raid5.c | 4 +--- > > 1 file changed, 1 insertion(+), 3 deletions(-) > > > > diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c > > index ec0f951..e7f527c 100644 > > --- a/drivers/md/raid5.c > > +++ b/drivers/md/raid5.c > > @@ -7947,12 +7947,10 @@ static void end_reshape(struct r5conf *conf) > > { > > > > if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { > > - struct md_rdev *rdev; > > > > spin_lock_irq(&conf->device_lock); > > conf->previous_raid_disks = conf->raid_disks; > > - rdev_for_each(rdev, conf->mddev) > > - rdev->data_offset = rdev->new_data_offset; > > + md_finish_reshape(conf->mddev); > > smp_wmb(); > > conf->reshape_progress = MaxSector; > > conf->mddev->reshape_position = MaxSector; > > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html