bin/146205: df(1) fails to display total space on a 100PB filesystem correctly

[Bruce Cran]

>Number:         146205
>Category:       bin
>Synopsis:       df(1) fails to display total space on a 100PB filesystem correctly
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat May 01 00:00:20 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Bruce Cran
>Release:        9.0-CURRENT
>Organization:
>Environment:
FreeBSD core.draftnet 9.0-CURRENT FreeBSD 9.0-CURRENT #0 r207449: Fri Apr 30 22:16:52 BST 2010     brucec at core.draftnet:/usr/obj/usr/src/head/sys/CORE  amd64
>Description:
df(1) correctly displays the number of 1K blocks in a 100PB filesystem, but displays wrong results when run with the "-h" flag:

> df tank
Filesystem 1K-blocks       Used           Avail Capacity  Mounted on
tank   107692009979824   19 107692009979805     0%    /tank

> df -h tank
Filesystem    Size    Used   Avail Capacity  Mounted on
tank      -741     19K    -741     0%    /tank

I suspect this is due to bugs in humanize_number from libdisk.
>How-To-Repeat:
On a ZFS filesystem, run "truncate -s100P mdfile && mdconfig -a -f mdfile" then create a pool on the md device.
>Fix:


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