change partition table on live disk (resize root partition)

change partition table on live disk (resize root partition)

[Vasiliy G Tolstov]

Hello.

If i need to resize root partition on live file system i do
fdisk /dev/sda delete old partition table and write new. After that
fdisk say's that system use old partition table before reread it via
partprobe or something else.

But if i modify root partition partprobe say's that it is already in use
and i need to reboot system to see changes and do resize fs.

Is that possible to reread partition table for root fs without
rebooting? I ca'n use lvm on something else, i'm use plain ext3 fs.


P.S. This is need for xen domU, i see that in blkfront_connect function
this code:

                /*
                 * Potentially, the back-end may be signalling
                 * a capacity change; update the capacity.
                 */
                err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
                                   "sectors", "%Lu", &sectors);
                if (XENBUS_EXIST_ERR(err))
                        return;
                printk(KERN_INFO "Setting capacity to %Lu\n",
                       sectors);
                set_capacity(info->gd, sectors);
                revalidate_disk(info->gd);

If i'm add after revalidate disk some function to reread partiotion
table does it can work?

Sorry for may be stupid question...


-- 
Vasiliy G Tolstov <v.tolstov@selfip.ru>
Selfip.Ru