x86, pat: Generalize the use of page flag PG_uncached

Only IA64 was using PG_uncached as of now. We now intend to use this bit
in x86 as well, to keep track of memory type of those addresses that
have page struct for them. So, generalize the use of that bit across
ia64 and x86.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 170042b..e624611 100644 (file)
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -112,6 +112,10 @@ config IA64_UNCACHED_ALLOCATOR
        bool
        select GENERIC_ALLOCATOR
 
+config ARCH_USES_PG_UNCACHED
+       def_bool y
+       depends on IA64_UNCACHED_ALLOCATOR
+
 config AUDIT_ARCH
        bool
        default y

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index c07f722..8e15953 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1414,6 +1414,10 @@ config X86_PAT
 
          If unsure, say Y.
 
+config ARCH_USES_PG_UNCACHED
+       def_bool y
+       depends on X86_PAT
+
 config EFI
        bool "EFI runtime service support"
        depends on ACPI

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index e2e5ce5..2b87acf 100644 (file)
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -99,7 +99,7 @@ enum pageflags {
 #ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT
        PG_mlocked,             /* Page is vma mlocked */
 #endif
-#ifdef CONFIG_IA64_UNCACHED_ALLOCATOR
+#ifdef CONFIG_ARCH_USES_PG_UNCACHED
        PG_uncached,            /* Page has been mapped as uncached */
 #endif
        __NR_PAGEFLAGS,
@@ -257,7 +257,7 @@ PAGEFLAG_FALSE(Mlocked)
        SETPAGEFLAG_NOOP(Mlocked) TESTCLEARFLAG_FALSE(Mlocked)
 #endif
 
-#ifdef CONFIG_IA64_UNCACHED_ALLOCATOR
+#ifdef CONFIG_ARCH_USES_PG_UNCACHED
 PAGEFLAG(Uncached, uncached)
 #else
 PAGEFLAG_FALSE(Uncached)