[set|get]_page_memtype() are used by PAT and implemented under
CONFIG_X86_PAT only. set_page_memtype() only handles three
memory types, WB, WC and UC-, due to a limitation in the page flags.
This patch moves [set|get]_page_memtype() to pat.c. This keeps
them as PAT-internal functions and manages the limitation checked
by the caller properly.
Signed-off-by: Toshi Kani <toshi.k...@hp.com>
Suggested-by: Thomas Gleixner <t...@linutronix.de>
---
arch/x86/include/asm/cacheflush.h | 69 -------------------------------------
arch/x86/mm/pat.c | 58 +++++++++++++++++++++++++++++++
2 files changed, 58 insertions(+), 69 deletions(-)
diff --git a/arch/x86/include/asm/cacheflush.h
b/arch/x86/include/asm/cacheflush.h
index 157644b..47c8e32 100644
--- a/arch/x86/include/asm/cacheflush.h
+++ b/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:
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index f43ab47..91c01b9 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -16,6 +16,7 @@
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/rbtree.h>
+#include <linux/page-flags.h>
#include <asm/cacheflush.h>
#include <asm/processor.h>
@@ -290,6 +291,63 @@ static int pat_pagerange_is_ram(resource_size_t start,
resource_size_t end)
}
/*
+ * 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);
+}
+
+/*
* For RAM pages, we use page flags to mark the pages with appropriate type.
* Here we do two pass:
* - Find the memtype of all the pages in the range, look for any conflicts
--
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