ioremap can't be used to map ring pages on ARM because it uses device
memory caching attributes (MT_DEVICE*).
Introduce a Xen specific abstraction to map ring pages, called
xen_remap, that is defined as ioremap on x86 (no behavioral changes).
On ARM it explicitly calls __arm_ioremap with the right caching
attributes: MT_MEMORY.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This makes common code less ifdef-y and is consistent with PVHVM on
x86.
Also note that phys_to_machine_mapping_valid should take a pfn
argument and make it do so.
Add __set_phys_to_machine, make set_phys_to_machine a simple wrapper
(on systems with non-nop implementations the outer one can allocate
new p2m pages).
Make __set_phys_to_machine check for identity mapping or invalid only.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
ARM Xen guests always use paging in hardware, like PV on HVM guests in
the X86 world.
Changes in v3:
- improve comments.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>