Re: [PATCH v3 1/6] mm: add definition of PMD_PAGE_ORDER

From: Mike Rapoport <redacted>

The definition of PMD_PAGE_ORDER denoting the number of base pages in the
second-level leaf page is already used by DAX and maybe handy in other
cases as well.

Several architectures already have definition of PMD_ORDER as the size of
second level page table, so to avoid conflict with these definitions use
PMD_PAGE_ORDER name and update DAX respectively.

Signed-off-by: Mike Rapoport <redacted>
---
 fs/dax.c                | 10 +++++-----
 include/linux/pgtable.h |  3 +++
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/fs/dax.c b/fs/dax.c
index 11b16729b86f..b91d8c8dda45 100644
--- a/fs/dax.c
+++ b/fs/dax.c

@@ -50,7 +50,7 @@ static inline unsigned int pe_order(enum page_entry_size pe_size)
 #define PG_PMD_NR	(PMD_SIZE >> PAGE_SHIFT)
 
 /* The order of a PMD entry */
-#define PMD_ORDER	(PMD_SHIFT - PAGE_SHIFT)
+#define PMD_PAGE_ORDER	(PMD_SHIFT - PAGE_SHIFT)

diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 56c1e8eb7bb0..79f8443609e7 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h

@@ -28,6 +28,9 @@
 #define USER_PGTABLES_CEILING	0UL
 #endif
 
+/* Number of base pages in a second level leaf page */
+#define PMD_PAGE_ORDER	(PMD_SHIFT - PAGE_SHIFT)
+
 /*
  * A page table page can be thought of an array like this: pXd_t[PTRS_PER_PxD]
  *