Date: Fri, 3 Sep 2004 20:38:39 +0200 From: Stefan Bethke <stb@lassitu.de> To: Sam <sah@softcardsystems.com> Cc: freebsd-arch@freebsd.org Subject: Re: mknod minors Message-ID: <794C3F76-FDD8-11D8-A251-000A95C893E4@lassitu.de> In-Reply-To: <Pine.LNX.4.60.0409031256140.16299@athena> References: <Pine.LNX.4.60.0409031256140.16299@athena>
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Am 03.09.2004 um 20:03 schrieb Sam: > OK, I understand the layout of the minor number > according to sys/disklabel.h, but what's with > the numbering scheme here? > > freebsd# ls -l /dev/ad0* > crw-r----- 2 root operator 116, 0x00010002 Nov 17 2002 /dev/ad0 > crw-r----- 2 root operator 116, 0 Nov 17 2002 /dev/ad0a > crw-r----- 2 root operator 116, 1 Nov 17 2002 /dev/ad0b > crw-r----- 2 root operator 116, 2 Nov 17 2002 /dev/ad0c > crw-r----- 2 root operator 116, 3 Nov 17 2002 /dev/ad0d > crw-r----- 2 root operator 116, 4 Nov 17 2002 /dev/ad0e > crw-r----- 2 root operator 116, 5 Nov 17 2002 /dev/ad0f > crw-r----- 2 root operator 116, 6 Nov 17 2002 /dev/ad0g > crw-r----- 2 root operator 116, 7 Nov 17 2002 /dev/ad0h > crw-r----- 2 root operator 116, 0x00020002 Nov 17 2002 /dev/ad0s1 > crw-r----- 2 root operator 116, 0x00020000 Nov 17 2002 /dev/ad0s1a > crw-r----- 2 root operator 116, 0x00020001 Nov 17 2002 /dev/ad0s1b > crw-r----- 2 root operator 116, 0x00020002 Nov 17 2002 /dev/ad0s1c > crw-r----- 2 root operator 116, 0x00020003 Nov 17 2002 /dev/ad0s1d > crw-r----- 2 root operator 116, 0x00020004 Nov 17 2002 /dev/ad0s1e > crw-r----- 2 root operator 116, 0x00020005 Nov 17 2002 /dev/ad0s1f > crw-r----- 2 root operator 116, 0x00020006 Nov 17 2002 /dev/ad0s1g > crw-r----- 2 root operator 116, 0x00020007 Nov 17 2002 /dev/ad0s1h > crw-r----- 2 root operator 116, 0x00030002 Nov 17 2002 /dev/ad0s2 > crw-r----- 2 root operator 116, 0x00040002 Nov 17 2002 /dev/ad0s3 > crw-r----- 2 root operator 116, 0x00050002 Nov 17 2002 /dev/ad0s4 > > Why is the whole disk slice 1, but partitions within it are > slice 0? Why isn't the whole disk slice 0 and slice 1 > is ... slice 1 (ad0s1)? What makes ad0s2 be partition 3? I'm by no means an expert in this field, just a long-time user, but I'll try to give some answers: ad0[a-z] are the "compatibility" partitions. I'd guess that that's the reason they come first, number-wise. The compatibility partitions will access the first FreeBSD slice on the disk, if any. They have been depracated long ago (I believe somewhere around 3-current), and I'd think you do not need to provide them, since programs having distict ideas about what disk devices should be called should long be gone. Since the MS-DOS partitioning scheme does not provide an entry for the entire disk (like the BSD c partition would), it has to go somewhere; using another "slice" number-wise seems logical. And that makes ad0s2 the "third slice" (and so on). Stefan -- Stefan Bethke <stb@lassitu.de> Fon +49 170 346 0140
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