From a5430dda8a3a1cdd532e37270e6f36436241b6e7 Mon Sep 17 00:00:00 2001 From: Jérôme Glisse Date: Fri, 8 Sep 2017 16:12:17 -0700 Subject: mm/migrate: support un-addressable ZONE_DEVICE page in migration MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Allow to unmap and restore special swap entry of un-addressable ZONE_DEVICE memory. Link: http://lkml.kernel.org/r/20170817000548.32038-17-jglisse@redhat.com Signed-off-by: Jérôme Glisse Cc: Kirill A. Shutemov Cc: Aneesh Kumar Cc: Balbir Singh Cc: Benjamin Herrenschmidt Cc: Dan Williams Cc: David Nellans Cc: Evgeny Baskakov Cc: Johannes Weiner Cc: John Hubbard Cc: Mark Hairgrove Cc: Michal Hocko Cc: Paul E. McKenney Cc: Ross Zwisler Cc: Sherry Cheung Cc: Subhash Gutti Cc: Vladimir Davydov Cc: Bob Liu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/migrate.h | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'include/linux/migrate.h') diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 8f73cebfc3f5..8dc8f0a3f1af 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -159,12 +159,18 @@ static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm, #ifdef CONFIG_MIGRATION +/* + * Watch out for PAE architecture, which has an unsigned long, and might not + * have enough bits to store all physical address and flags. So far we have + * enough room for all our flags. + */ #define MIGRATE_PFN_VALID (1UL << 0) #define MIGRATE_PFN_MIGRATE (1UL << 1) #define MIGRATE_PFN_LOCKED (1UL << 2) #define MIGRATE_PFN_WRITE (1UL << 3) -#define MIGRATE_PFN_ERROR (1UL << 4) -#define MIGRATE_PFN_SHIFT 5 +#define MIGRATE_PFN_DEVICE (1UL << 4) +#define MIGRATE_PFN_ERROR (1UL << 5) +#define MIGRATE_PFN_SHIFT 6 static inline struct page *migrate_pfn_to_page(unsigned long mpfn) { -- cgit v1.2.3