generic: add phys_addr_t for holding physical addresses

Add a kernel-wide "phys_addr_t" which is guaranteed to be able to hold
any physical address.  By default it equals the word size of the
architecture, but a 32-bit architecture can set ARCH_PHYS_ADDR_T_64BIT
if it needs a 64-bit phys_addr_t.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index ed92864d1325..a0ffb5188c8c 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -932,6 +932,9 @@ config X86_PAE
           has the cost of more pagetable lookup overhead, and also
           consumes more pagetable space per process.
 
+config ARCH_PHYS_ADDR_T_64BIT
+       def_bool X86_64 || X86_PAE
+
 # Common NUMA Features
 config NUMA
         bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"