Provide is_vma_noncached() static inline to allow generic code to
check whether the given vma consists of noncached memory.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
CC: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx>
CC: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CC: Paul Turner <pjt@xxxxxxxxxx>
CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CC: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
CC: Andi Kleen <andi@xxxxxxxxxxxxxx>
CC: Dave Watson <davejwatson@xxxxxx>
CC: Chris Lameter <cl@xxxxxxxxx>
CC: Ingo Molnar <mingo@xxxxxxxxxx>
CC: "H. Peter Anvin" <hpa@xxxxxxxxx>
CC: Ben Maurer <bmaurer@xxxxxx>
CC: Steven Rostedt <rostedt@xxxxxxxxxxx>
CC: Josh Triplett <josh@xxxxxxxxxxxxxxxx>
CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
CC: Russell King <linux@xxxxxxxxxxxxxxxx>
CC: Catalin Marinas <catalin.marinas@xxxxxxx>
CC: Will Deacon <will.deacon@xxxxxxx>
CC: Michael Kerrisk <mtk.manpages@xxxxxxxxx>
CC: Boqun Feng <boqun.feng@xxxxxxxxx>
CC: linux-mm@xxxxxxxxx
---
include/linux/mm.h | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0416a7204be3..18acf4f339f8 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2551,6 +2551,30 @@ static inline struct page *follow_page(struct vm_area_struct *vma,
return follow_page_mask(vma, address, foll_flags, &unused_page_mask);
}
+static inline bool pgprot_same(pgprot_t a, pgprot_t b)
+{
+ return pgprot_val(a) == pgprot_val(b);
+}
+
+#ifdef pgprot_noncached
+static inline bool is_vma_noncached(struct vm_area_struct *vma)
+{
+ pgprot_t pgprot = vma->vm_page_prot;
+
+ /* Check whether architecture implements noncached pages. */
+ if (pgprot_same(pgprot_noncached(PAGE_KERNEL), PAGE_KERNEL))
+ return false;
+ if (!pgprot_same(pgprot, pgprot_noncached(pgprot)))
+ return false;
+ return true;
+}
+#else
+static inline bool is_vma_noncached(struct vm_area_struct *vma)
+{
+ return false;
+}
+#endif
+
#define FOLL_WRITE 0x01 /* check pte is writable */
#define FOLL_TOUCH 0x02 /* mark page accessed */
#define FOLL_GET 0x04 /* do get_page on page */
--
2.11.0
