From owner-freebsd-hackers Tue Aug 24 16:29:58 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 551DF15B26 for ; Tue, 24 Aug 1999 16:29:51 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.3/8.9.1) id QAA19447; Tue, 24 Aug 1999 16:29:31 -0700 (PDT) (envelope-from dillon) Date: Tue, 24 Aug 1999 16:29:31 -0700 (PDT) From: Matthew Dillon Message-Id: <199908242329.QAA19447@apollo.backplane.com> To: Matthew Dillon Cc: David Greenman , FreeBSD Hackers List Subject: more... Re: Possibility of increasing default MAXPARTITIONS from 8 to 16 References: <199908242254.PAA16075@implode.root.com> <199908242303.QAA19246@apollo.backplane.com> <199908242322.QAA19396@apollo.backplane.com> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG : 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 Grrr. #ifdef PC98, NDOSPART is set to 16 instead of 4, requiring 5 bits (0,1,2-17). This leaves one bit that we can usurp. I'd rather have 2 bits, but I'll take 1 if I can get it. -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message