more... Re: Possibility of increasing default MAXPARTITIONS from 8 to 16

[Matthew Dillon]

:    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 
                                        <[EMAIL PROTECTED]>


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