swiotlb: Add is_swiotlb_active() function
BugLink: https://bugs.launchpad.net/bugs/1821607
commit
492366f7b4237257ef50ca9c431a6a0d50225aca upstream.
This function will be used from dma_direct code to determine
the maximum segment size of a dma mapping.
Cc: stable@vger.kernel.org
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>