From owner-freebsd-hackers Tue Aug 24 16:23:10 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from apollo.backplane.com (apollo.backplane.com [209.157.86.2]) by hub.freebsd.org (Postfix) with ESMTP id C2BCB1508B for ; Tue, 24 Aug 1999 16:23:08 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.3/8.9.1) id QAA19396; Tue, 24 Aug 1999 16:22:44 -0700 (PDT) (envelope-from dillon) Date: Tue, 24 Aug 1999 16:22:44 -0700 (PDT) From: Matthew Dillon Message-Id: <199908242322.QAA19396@apollo.backplane.com> To: David Greenman , FreeBSD Hackers List Subject: Re: Possibility of increasing default MAXPARTITIONS from 8 to 16 References: <199908242254.PAA16075@implode.root.com> <199908242303.QAA19246@apollo.backplane.com> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG :: It seems reasonable to me, although there may be issues with finding a bit ::in the minor number - I think they've pretty much all been taken. :: ::-DG :: ::David Greenman : : Cripes! Now that is really annoying. da0a is 4,0 and da1a is 4,8. : : -Matt minor device number: t = type u = unit (upper bits split off from lower) s = slice (assuming only 8 slices) 0 noslice 1 whole disk 2-5 s1,s2,s3,s4 6-8 unused p = partition - = cannot be used tttttttu uuusssss -------- uuuuuppp minor layout for disks 11111111 11111111 -------- 11111111 mask for uminor Our only hope as far as I can tell is to take the upper two bits of the slice (bits 19 and 20) and use them for the partition instead. As far as I can tell, only slices 0-5 are used, requiring only 3 bits. Can someone check my work? Are bits 19 and 20 unused by any disk devices? -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message