tree 5481262624654fc570be5aa7e1a5513687df263d
parent 12e13ac84ca70e6641a4750e9317aa2d2c1f6f50
author Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> 1314303234 -0400
committer Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> 1314375042 -0400

xen-swiotlb: When doing coherent alloc/dealloc check before swizzling the MFNs.

The process to swizzle a Machine Frame Number (MFN) is not always
necessary. Especially if we know that we actually do not have to do it.
In this patch we check the MFN against the device's coherent
DMA mask and if the requested page(s) are contingous. If it all checks
out we will just return the bus addr without doing the memory
swizzle.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>