Subject: Re: MAXBSIZE Was Re: bread() returns EINVAL during vfs mount
To: Reinoud Zandijk <>
From: Thor Lancelot Simon <>
List: tech-kern
Date: 08/27/2005 12:13:03
On Sat, Aug 27, 2005 at 05:56:44PM +0200, Reinoud Zandijk wrote:
> I wonder how i can implement sector sizes bigger than MAXBSIZE (normally 
> around 4k AFAIK) with normal bread and bwrite calls though.

I'm sorry, what?  I am unaware of any port that has a MAXBSIZE smaller
than 31K.

You can hand device drivers I/O requests of up to MAXPHYS in size (in
practice, you can hand them larger requests, too, but don't do that).
See the FFS code for examples.