Messages in this thread | | | Date | Mon, 29 Apr 2013 17:34:50 +0200 | From | Philippe De Muyter <> | Subject | Re: [PATCH 2/5] Add aix lvm partitions support files |
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Hi Karel
On Mon, Apr 29, 2013 at 02:36:51PM +0200, Karel Zak wrote: > On Mon, Apr 29, 2013 at 01:40:41PM +0200, Philippe De Muyter wrote: > > > why not memset(pps_found, ....)? I also see magical constant 16 > > > > Actually 16 is the maximum partition count allowed in a disk by linux, > > or should it be 15 ? Is there already a constant for that ? > > The AIX disk I tested with had only :) 11 partitions. > > I don't think it's correct to expect any hardcoded limit. > > The struct parsed_partitions->parts is allocated according to > disk_max_parts() where the limit depends on number of minor numbers or > it's DISK_MAX_PARTS (=256). > > There is no problem to create disk with many partitions: > > # modprobe scsi_debug dev_size_mb=300 > # (echo -e 'g\n'; for i in {1..100}; do echo -e "n\n\n\n+1M"; done; \ > echo -e 'w\nq\n') | fdisk /dev/sdb > > # lsblk -n /dev/sdb | wc -l > 101
how are they named then ?
on my system (a 2.6.24 kernel which is the last one that support my powerpc PReP machine because PReP support got removed with the merge of /arch/ppc and /arch/powerpc :( ), I get :
root:~# ls -l /dev/sd[ab]* brw-r----- 1 root disk 8, 0 Apr 25 22:22 /dev/sda brw-r----- 1 root disk 8, 10 Apr 25 22:22 /dev/sda10 brw-r----- 1 root disk 8, 11 Apr 25 22:22 /dev/sda11 brw-r----- 1 root disk 8, 3 Apr 25 22:22 /dev/sda3 brw-r----- 1 root disk 8, 4 Apr 25 22:22 /dev/sda4 brw-r----- 1 root disk 8, 5 Apr 25 22:22 /dev/sda5 brw-r----- 1 root disk 8, 6 Apr 25 22:22 /dev/sda6 brw-r----- 1 root disk 8, 7 Apr 25 22:22 /dev/sda7 brw-r----- 1 root disk 8, 8 Apr 25 22:22 /dev/sda8 brw-r----- 1 root disk 8, 9 Apr 25 22:22 /dev/sda9 brw-r----- 1 root disk 8, 16 Apr 25 22:22 /dev/sdb brw-r----- 1 root disk 8, 26 Apr 25 22:22 /dev/sdb10 brw-r----- 1 root disk 8, 27 Apr 25 22:22 /dev/sdb11 brw-r----- 1 root disk 8, 19 Apr 25 22:22 /dev/sdb3 brw-r----- 1 root disk 8, 20 Apr 25 22:22 /dev/sdb4 brw-r----- 1 root disk 8, 21 Apr 25 22:22 /dev/sdb5 brw-r----- 1 root disk 8, 22 Apr 25 22:22 /dev/sdb6 brw-r----- 1 root disk 8, 23 Apr 25 22:22 /dev/sdb7 brw-r----- 1 root disk 8, 24 Apr 25 22:22 /dev/sdb8 brw-r----- 1 root disk 8, 25 Apr 25 22:22 /dev/sdb9 root:~#
so sda is 8,0 and sdb is 8,16
and if, while discovering partitions of /dev/sda, I try to make a partition 16 or higher, it is silently discarded by 'put_partition'.
Is that changed ?
Philippe
-- Philippe De Muyter +32 2 6101532 Macq SA rue de l'Aeronef 2 B-1140 Bruxelles
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