diff mbox series

[v1,07/10] powerpc/mm: Prepare maybe_pte_to_page() for PG_reserved changes

Message ID 20191024120938.11237-8-david@redhat.com (mailing list archive)
State New, archived
Headers show
Series mm: Don't mark hotplugged pages PG_reserved (including ZONE_DEVICE) | expand

Commit Message

David Hildenbrand Oct. 24, 2019, 12:09 p.m. UTC 
Right now, ZONE_DEVICE memory is always set PG_reserved. We want to
change that.

Rewrite maybe_pte_to_page() to make sure the function produces the
same result once we stop setting ZONE_DEVICE pages PG_reserved.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
 arch/powerpc/mm/pgtable.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index e3759b69f81b..613c98fa7dc0 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -55,10 +55,12 @@  static struct page *maybe_pte_to_page(pte_t pte)
 	unsigned long pfn = pte_pfn(pte);
 	struct page *page;
 
-	if (unlikely(!pfn_valid(pfn)))
-		return NULL;
-	page = pfn_to_page(pfn);
-	if (PageReserved(page))
+	/*
+	 * We reject any pages that are not online (not managed by the buddy).
+	 * This includes ZONE_DEVICE pages.
+	 */
+	page = pfn_to_online_page(pfn);
+	if (unlikely(!page || PageReserved(page)))
 		return NULL;
 	return page;
 }