Subject: umass buffers (Was: Re: Nikon D70)
To: None <>
From: Jukka Marin <>
List: netbsd-users
Date: 07/22/2004 15:57:33

Is it possible to do the following as a workaround for the "umass0: no
buffer memory" problem:

- Allocate a pool of umass buffers (64k each) at boot time (kind of "mbufs")
- When a umass device is plugged in, a buffer is allocated from the pool
- When a umass device is disconnected, the buffer is deallocated back to
  the pool

The number of buffers could be configurable using a kernel option.  Without
this option, the code would work the same way it "works" now.

I don't think allocating 64k or even 256k for umass buffers would be a
problem on current machines.  At least it would let us use umass devices
without reboots or other kludges :-I