Re: [RFC 1/2] virtio_console: Add support for DMA memory allocation

"Michael S. Tsirkin" [off-list ref] writes:

Also let's add a wrapper at top of file so ifdefs
do not litter the code like this. For example:

#ifdef CONFIG_HAS_DMA
#define VIRTIO_CONSOLE_HAS_DMA (1)
#else
#define VIRTIO_CONSOLE_HAS_DMA (0)
#endif

Now use if instead of ifdef.

The driver certainly shouldn't offer VIRTIO_CONSOLE_F_DMA_MEM if you
don't have DMA!

Cheers,
Rusty.