Re: [PATCH] virtio_console: Add support for multiple ports forgeneric guest and host communication

[Alan Cox]

> Alan, I'm not sure how many ports at a time people would want to use so
> allocating one major device for this seems OK?

We have very large minor number ranges now so one dynamic major should do
you for a while yet. Probably forever but thats always asking for a
"640K.." moment ;)


> +static ssize_t fill_readbuf(struct virtio_console_port *port,
> +			    char *out_buf, size_t out_count, bool to_user)
> +{

Save yourself serious grief - and the FIXME pain noted below - unless you
are shipping huge objects use a bounce buffer and kill off the to_user
stuff - modern CPUs are so fast doing cache transfers it really isn't
worth the suffering for small stuff.

> +			ret = copy_to_user(out_buf + out_offset,
> +					   buf->buf + buf->offset,
> +					   copy_size);
> +			/* FIXME: Deal with ret != 0 */
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