kern/81496: acd (atapicd) device lacks devstat
avg at icyb.net.ua
Thu May 26 12:00:11 GMT 2005
>Synopsis: acd (atapicd) device lacks devstat
>Arrival-Date: Thu May 26 12:00:06 GMT 2005
>Originator: Andriy Gapon
acd device does not register itself as a geom disk with create_disk()
Soeren said a long while ago that there are some reasons for that:
I am not sure how valid those reasons are, because cd device is a geom disk and it essentially implements very similar interface although for a different bus.
I don't want to venture further in acd vs. geom disk situation, but not being a geom disk acd doesn't have get automatic devstat bookkeeping (as cd, ad etc do). It doesn't have any devstat bookkeeping of its own too.
On a system with ATAPI CDROM and atapicd device in kernel do the following:
1. sysctl kern.disks - acd* won't show up in the list returned
2. iostat -d - acd* won't be there
3. inspect atapi-cd.c sources
sorry, no patch at this time
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