On Wed, 18 Apr 2001, Robert Watson wrote:

> On Wed, 18 Apr 2001, Poul-Henning Kamp wrote:

> address spaces, can be opened/closed and retain a seeking position, can be

This is what I get for sending messages in the morning after staying up
late -- needless to say, you can ignore the "retain a seeking position" 
statement: vnodes generally don't operate with a notion of "position",
that occurs at the struct file level. 

It's arguable, if you had stateful vnodes, that you might want to push the
seek operation down from the open file layer, as devices might want to
implement the seeking service themselves.  In any case, this is not a
problem that moving the device operations into the struct file array will
fix--in fact, it's arguable for devices wanting to offer services to
different consumers on the same instance (such as /dev/vmmon), you want
the vnode reference counting notion of open/close + the sprinkled state
vnode design we've discussed before, which would allow VFS and the struct
file layer to do the state management binding state to consumers, rather
than teaching the device layer how to do that.

Robert N M Watson             FreeBSD Core Team, TrustedBSD Project
[EMAIL PROTECTED]      NAI Labs, Safeport Network Services


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