No downtme migration of mounted filesystem to new storage type

On LVM 1.0 Volume group, the task is no downtime storage migration.
 Hitachi to Pure Solid State storage. Mirror/UX required.
 Disks are almostthe same size:

dbrestore:root > diskinfo /dev/rdisk/disk42
 SCSI describe of /dev/rdisk/disk42:
 vendor: HITACHI
 product id: OPEN-V
 type: direct access
 size: 16777216 Kbytes
 bytes per sector: 512
 dbrestore:root > diskinfo /dev/rdisk/disk52
 SCSI describe of /dev/rdisk/disk52:
 vendor: PURE
 product id: FlashArray
 type: direct access
 size: 10485760 Kbytes
 bytes per sector: 512

pvcreate /dev/rdisk/disk52
 vgextend /dev/vgtest /dev/disk/disk52

Before state:
 dbrestore:root > vgdisplay -v vgtest
 --- Volume groups ---
 VG Name /dev/vgtest
 VG Write Access read/write
 VG Status available
 Max LV 255
 Cur LV 1
 Open LV 1
 Max PV 16
 Cur PV 2
 Act PV 2
 Max PE per PV 4095
 VGDA 4
 PE Size (Mbytes) 4
 Total PE 6654
 Alloc PE 1024
 Free PE 5630
 Total PVG 0
 Total Spare PVs 0
 Total Spare PVs in use 0
 VG Version 1.0
 VG Max Size 262080m
 VG Max Extents 65520

--- Logical volumes ---
 LV Name /dev/vgtest/lvtest
 LV Status available/syncd
 LV Size (Mbytes) 4096
 Current LE 1024
 Allocated PE 1024
 Used PV 1

--- Physical volumes ---
 PV Name /dev/disk/disk42
 PV Status available
 Total PE 4095
 Free PE 4095
 Autoswitch On
 Proactive Polling On

PV Name /dev/disk/disk52
 PV Status available
 Total PE 2559
 Free PE 1535
 Autoswitch On
 Proactive Polling On

dbrestore:root > ioscan -NfnCdisk /dev/disk/disk42
 Class I H/W Path Driver S/W State H/W Type Description
 ===================================================================
 disk 42 64000/0xfa00/0x21 esdisk CLAIMED DEVICE HITACHI OPEN-V
 /dev/disk/disk42 /dev/rdisk/disk42
 dbrestore:root > ioscan -NfnCdisk /dev/disk/disk52
 Class I H/W Path Driver S/W State H/W Type Description
 ===================================================================
 disk 52 64000/0xfa00/0x35 esdisk CLAIMED DEVICE PURE FlashArray
 /dev/disk/disk52 /dev/rdisk/disk52
 dbrestore:root > bdf | grep test
 /dev/vgtest/lvtest 4194304 19544 3913845 0% /test
 dbrestore:root > lvdisplay -v /dev/vgtest/lvtest
 --- Logical volumes ---
 LV Name /dev/vgtest/lvtest
 VG Name /dev/vgtest
 LV Permission read/write
 LV Status available/syncd
 Mirror copies 0
 Consistency Recovery MWC
 Schedule parallel
 LV Size (Mbytes) 4096
 Current LE 1024
 Allocated PE 1024
 Stripes 0
 Stripe Size (Kbytes) 0
 Bad block on
 Allocation strict
 IO Timeout (Seconds) default

--- Distribution of logical volume ---
 PV Name LE on PV PE on PV
 /dev/disk/disk42 1024 1024

--- Logical extents ---
 LE PV1 PE1 Status 1
 00000 /dev/disk/disk42 00000 current
 00001 /dev/disk/disk42 00001 current
 00002 /dev/disk/disk42 00002 current
 ...
 01022 /dev/disk/disk42 01022 current
 01023 /dev/disk/disk42 01023 current

dbrestore:root > lvextend -m 1 /dev/vgtest/lvtest /dev/disk/disk52
 The newly allocated mirrors are now being synchronized.This operation will
 take some time. Please wait ....
 Logical volume "/dev/vgtest/lvtest" has been successfully extended.
 Volume Group configuration for /dev/vgtest has been saved in /etc/lvmconf/vgtest.conf
 dbrestore:root > lvdisplay -v /dev/vgtest/lvtest
 --- Logical volumes ---
 LV Name /dev/vgtest/lvtest
 VG Name /dev/vgtest
 LV Permission read/write
 LV Status available/syncd
 Mirror copies 1
 Consistency Recovery MWC
 Schedule parallel
 LV Size (Mbytes) 4096
 Current LE 1024
 Allocated PE 2048
 Stripes 0
 Stripe Size (Kbytes) 0
 Bad block on
 Allocation strict
 IO Timeout (Seconds) default

--- Distribution of logical volume ---
 PV Name LE on PV PE on PV
 /dev/disk/disk42 1024 1024
 /dev/disk/disk52 1024 1024

--- Logical extents ---
 LE PV1 PE1 Status 1 PV2 PE2 Status 2
 00000 /dev/disk/disk42 00000 current /dev/disk/disk52 00000 current
 00001 /dev/disk/disk42 00001 current /dev/disk/disk52 00001 current
 00002 /dev/disk/disk42 00002 current /dev/disk/disk52 00002 current
 ...
 01023 /dev/disk/disk42 01023 current /dev/disk/disk52 01023 current

dbrestore:root > bdf | grep test
 /dev/vgtest/lvtest 4194304 19544 3913845 0% /test
 dbrestore:root > lvreduce -m 0 /dev/vgtest/lvtest /dev/disk/disk42
 Logical volume "/dev/vgtest/lvtest" has been successfully reduced.
 Volume Group configuration for /dev/vgtest has been saved in /etc/lvmconf/vgtest.conf
 dbrestore:root > bdf | grep test
 /dev/vgtest/lvtest 4194304 19544 3913845 0% /test
 dbrestore:root > lvdisplay -v /dev/vgtest/lvtest
 --- Logical volumes ---
 LV Name /dev/vgtest/lvtest
 VG Name /dev/vgtest
 LV Permission read/write
 LV Status available/syncd
 Mirror copies 0
 Consistency Recovery MWC
 Schedule parallel
 LV Size (Mbytes) 4096
 Current LE 1024
 Allocated PE 1024
 Stripes 0
 Stripe Size (Kbytes) 0
 Bad block on
 Allocation strict
 IO Timeout (Seconds) default

--- Distribution of logical volume ---
 PV Name LE on PV PE on PV
 /dev/disk/disk52 1024 1024

--- Logical extents ---
 LE PV1 PE1 Status 1
 00000 /dev/disk/disk52 00000 current
 00001 /dev/disk/disk52 00001 current

...
 01023 /dev/disk/disk52 01023 current

dbrestore:root > bdf | grep test
 /dev/vgtest/lvtest 4194304 19544 3913845 0% /test
 dbrestore:root >