kern/136942: [zfs] zvol resize not reflected until reboot

[Bernard Buri]

>Number:         136942
>Category:       kern
>Synopsis:       [zfs] zvol resize not reflected until reboot
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Mon Jul 20 21:10:06 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Bernard Buri
>Release:        7.2-STABLE
>Organization:
ask!
>Environment:
FreeBSD *** 7.2-STABLE FreeBSD 7.2-STABLE #3: Tue Jul 14 07:51:51 CEST 2009     root@***:/usr/obj/usr/src/sys/GENERIC  amd64

>Description:
Zfs allows to create volumes on a pool by giving a size argument to zfs create. These volumes are similar to vnode backed mdconfig(8) memory disks. I verified that on open solaris, these volumes can be resized by setting the volsize property, and the block device will reflect the size update immediately. However, on FreeBSD, the resize will have no effect until the pool is exported and imported again. This has to be done by rebooting, when the root device is on the pool.
>How-To-Repeat:
# zfs create -V 1g pool/testvol
# diskinfo -v /dev/zvol/pool/testvol
/dev/zvol/pool/testvol
	512         	# sectorsize
	1073741824  	# mediasize in bytes (1.0G)
	2097152     	# mediasize in sectors

#zfs set volsize=2g pool/testvol
# diskinfo -v /dev/zvol/pool/testvol
/dev/zvol/pool/testvol
	512         	# sectorsize
	1073741824  	# mediasize in bytes (1.0G)
	2097152     	# mediasize in sectors


>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: