On Tue, Mar 30, 2010 at 6:53 AM, Kwolek, Adam <adam.kwolek@xxxxxxxxx> wrote: > I found that setting new raid volume size using array_size entry in sysfs causes that inode references in vfs can be lost. > > Conditions: > SLES 11 (32bit) machine with > kernel: 2.6.33 > mdadm : 3.1.2 > 5 SATA hdds in system: > SLES 11 on /dev/sda > 4 test disks /dev/hdb - /dev/hde > > Reproduction: > 1. Configure: > # create native raid5 volume, with specified size (relatively small) > mdadm -C /dev/md/raid5vol_0 -amd -l 5 --chunk 64 --size 104857 -n 3 /dev/sdb /dev/sdc /dev/sde -R > > # Create file system > mkfs /dev/md/raid5vol_0 > > # mount it and copy some files there > mount /dev/md/raid5vol_0 /mnt/vol > cp * /mnt/vol > > 2. Try to change volume size. This should affect volume, but not vfs > echo "157285" >/sys/block/md127/md/array_size Of course this affects the filesystem. You have reduced the size of the volume from 209,664KB to 157,285KB. Perhaps you are confusing the --size parameter to mdadm (which is per member) and the md/array_size attribute which is the total volume size?? > In the few tries (maybe at first shot) you would probably find that when you are trying to execute ls command on mounted volume message in user space appears: > ls: cannot access 'copied file name': Input/output error > In kernel space messages can be found: > In response to size change: > Mar 30 16:27:03 linux kernel: md127: detected capacity change from 214695936 to 161059840 > Mar 30 16:27:03 linux kernel: VFS: busy inodes on changed media or resized disk md127 Yes, the filesystem is horribly confused at this point because 50MB of space has disappeared. -- Dan -- 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
