x86: mm: Move PAT only functions to mm/pat.c

Commit e00c8cc9 "x86: Use new cache mode type in memtype related
functions" broke the ARCH=um build.

 arch/x86/include/asm/cacheflush.h:67:36: error: return type is an incomplete type
 static inline enum page_cache_mode get_page_memtype(struct page *pg)

The reason is simple. get_page_memtype() and set_page_memtype()
require enum page_cache_mode now, which is defined in
asm/pgtable_types.h. UM does not include that file for obvious reasons.

The simple solution is to move that functions to arch/x86/mm/pat.c
where the only callsites of this are located. They should have been
there in the first place.

Fixes: e00c8cc9 "x86: Use new cache mode type in memtype related functions"
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Richard Weinberger <richard@nod.at>

arch/x86/include/asm/cacheflush.h

@@ -5,75 +5,6 @@
 #include <asm-generic/cacheflush.h>
 #include <asm/special_insns.h>
 
-#ifdef CONFIG_X86_PAT
-/*
- * X86 PAT uses page flags WC and Uncached together to keep track of
- * memory type of pages that have backing page struct. X86 PAT supports 3
- * different memory types, _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC and
- * _PAGE_CACHE_MODE_UC_MINUS and fourth state where page's memory type has not
- * been changed from its default (value of -1 used to denote this).
- * Note we do not support _PAGE_CACHE_MODE_UC here.
- */
-
-#define _PGMT_DEFAULT		0
-#define _PGMT_WC		(1UL << PG_arch_1)
-#define _PGMT_UC_MINUS		(1UL << PG_uncached)
-#define _PGMT_WB		(1UL << PG_uncached | 1UL << PG_arch_1)
-#define _PGMT_MASK		(1UL << PG_uncached | 1UL << PG_arch_1)
-#define _PGMT_CLEAR_MASK	(~_PGMT_MASK)
-
-static inline enum page_cache_mode get_page_memtype(struct page *pg)
-{
-	unsigned long pg_flags = pg->flags & _PGMT_MASK;
-
-	if (pg_flags == _PGMT_DEFAULT)
-		return -1;
-	else if (pg_flags == _PGMT_WC)
-		return _PAGE_CACHE_MODE_WC;
-	else if (pg_flags == _PGMT_UC_MINUS)
-		return _PAGE_CACHE_MODE_UC_MINUS;
-	else
-		return _PAGE_CACHE_MODE_WB;
-}
-
-static inline void set_page_memtype(struct page *pg,
-				    enum page_cache_mode memtype)
-{
-	unsigned long memtype_flags;
-	unsigned long old_flags;
-	unsigned long new_flags;
-
-	switch (memtype) {
-	case _PAGE_CACHE_MODE_WC:
-		memtype_flags = _PGMT_WC;
-		break;
-	case _PAGE_CACHE_MODE_UC_MINUS:
-		memtype_flags = _PGMT_UC_MINUS;
-		break;
-	case _PAGE_CACHE_MODE_WB:
-		memtype_flags = _PGMT_WB;
-		break;
-	default:
-		memtype_flags = _PGMT_DEFAULT;
-		break;
-	}
-
-	do {
-		old_flags = pg->flags;
-		new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
-	} while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
-}
-#else
-static inline enum page_cache_mode get_page_memtype(struct page *pg)
-{
-	return -1;
-}
-static inline void set_page_memtype(struct page *pg,
-				    enum page_cache_mode memtype)
-{
-}
-#endif
-
 /*
  * The set_memory_* API can be used to change various attributes of a virtual
  * address range. The attributes include:

arch/x86/mm/pat.c

@@ -67,6 +67,75 @@ __setup("debugpat", pat_debug_setup);
 
 static u64 __read_mostly boot_pat_state;
 
+#ifdef CONFIG_X86_PAT
+/*
+ * X86 PAT uses page flags WC and Uncached together to keep track of
+ * memory type of pages that have backing page struct. X86 PAT supports 3
+ * different memory types, _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC and
+ * _PAGE_CACHE_MODE_UC_MINUS and fourth state where page's memory type has not
+ * been changed from its default (value of -1 used to denote this).
+ * Note we do not support _PAGE_CACHE_MODE_UC here.
+ */
+
+#define _PGMT_DEFAULT		0
+#define _PGMT_WC		(1UL << PG_arch_1)
+#define _PGMT_UC_MINUS		(1UL << PG_uncached)
+#define _PGMT_WB		(1UL << PG_uncached | 1UL << PG_arch_1)
+#define _PGMT_MASK		(1UL << PG_uncached | 1UL << PG_arch_1)
+#define _PGMT_CLEAR_MASK	(~_PGMT_MASK)
+
+static inline enum page_cache_mode get_page_memtype(struct page *pg)
+{
+	unsigned long pg_flags = pg->flags & _PGMT_MASK;
+
+	if (pg_flags == _PGMT_DEFAULT)
+		return -1;
+	else if (pg_flags == _PGMT_WC)
+		return _PAGE_CACHE_MODE_WC;
+	else if (pg_flags == _PGMT_UC_MINUS)
+		return _PAGE_CACHE_MODE_UC_MINUS;
+	else
+		return _PAGE_CACHE_MODE_WB;
+}
+
+static inline void set_page_memtype(struct page *pg,
+				    enum page_cache_mode memtype)
+{
+	unsigned long memtype_flags;
+	unsigned long old_flags;
+	unsigned long new_flags;
+
+	switch (memtype) {
+	case _PAGE_CACHE_MODE_WC:
+		memtype_flags = _PGMT_WC;
+		break;
+	case _PAGE_CACHE_MODE_UC_MINUS:
+		memtype_flags = _PGMT_UC_MINUS;
+		break;
+	case _PAGE_CACHE_MODE_WB:
+		memtype_flags = _PGMT_WB;
+		break;
+	default:
+		memtype_flags = _PGMT_DEFAULT;
+		break;
+	}
+
+	do {
+		old_flags = pg->flags;
+		new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
+	} while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
+}
+#else
+static inline enum page_cache_mode get_page_memtype(struct page *pg)
+{
+	return -1;
+}
+static inline void set_page_memtype(struct page *pg,
+				    enum page_cache_mode memtype)
+{
+}
+#endif
+
 enum {
 	PAT_UC = 0,		/* uncached */
 	PAT_WC = 1,		/* Write combining */