On 05-Feb-00 Warner Losh wrote:
>
> In msdosfs_vfsops.c we have:
> || !pmp->pm_Heads || pmp->pm_Heads > 255
>#ifdef PC98
> || !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) {
>#else
> || !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) {
>#endif
> error = EINVAL;
>
> What's so special about 63? Many scsi drives have more than 63
> sectors per track. The only reason that we don't see problems with
> this is that it appears that CAM appears to be using a geometry with
> 64 heads and 32 sectors and N cylendars. What's the justification
> here?
The PC BIOS (int 0x13 calls) only allows for 63 sectors numbered 1-63 for each
track (cylinder). That is most likely the reason for the 63.
> Warner
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