On Fri, Oct 21, 2005 at 01:48:45PM -0400, Luben Tuikov wrote:

quoted

why James has suggested implementing SMP as a block driver.  People get 
stuck into thinking "block driver == block device", which is wrong.  The 

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Linux block layer is nothing but a message queueing interface.

Now, just because James suggested implementing the SMP service as a block
device you think this is the right thing to do?

How about this: Why not as a char device?

you can implement a char device using the block layer.  See
drivers/scsi/{ch.c,osst.c,sg.c,st.c} for examples.

That beeing said I tried this approach.  It looks pretty cool when you
think about it, but the block layer is quite a bit too heavyweight for
queueing up a few SMP requests, and we need to carry too much useless
code around for it.