From: Peter Oberparleiter <oberpar@linux.ibm.com>
Subject: s390/mm: introduce defines to reflect the hardware mmu
Patch-mainline: v4.14-rc1
Git-commit: c67da7c7c5d4c0a45b079b21f6991cb7e753856e
References: FATE#326357, LTC#169111, bsc#1113500

Summary:     kernel: Add support for reading I/O configuration data
Description: LPARs that are running in IBM Dynamic Partition Manager (DPM) mode
             can access a firmware-generated I/O configuration data file that
             contains s390-specific information about available I/O devices
             such as qeth device numbers and parameters, and FCP device IDs.

             This data file is intended to remove the need for users to
             manually enter the corresponding device data during installation.

             This patch set makes the data file available at the following
             location:

               /sys/firmware/sclp_sd/config/data


Upstream-Description:

             s390/mm: introduce defines to reflect the hardware mmu

             Add various defines like e.g. _REGION1_SHIFT to reflect the hardware
             mmu. We have quite a bit code that does not make use of the Linux
             memory management primitives but directly modifies page, segment and
             region values.

             Most of this is open-coded like e.g. "1UL << 53". In order to clean
             this up introduce a couple of new defines. The existing Linux memory
             management defines are changed, so the mapping to the hardware
             implementation is reflected.

             Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
             Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
             Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
---
 arch/s390/include/asm/page.h    |   10 ++++-
 arch/s390/include/asm/pgalloc.h |    2 +
 arch/s390/include/asm/pgtable.h |   55 ++++++++++++++++++++++----------
 3 files changed, 48 insertions(+), 19 deletions(-)

--- a/arch/s390/include/asm/page.h
+++ b/arch/s390/include/asm/page.h
@@ -10,10 +10,14 @@
 #include <linux/const.h>
 #include <asm/types.h>
 
+#define _PAGE_SHIFT	12
+#define _PAGE_SIZE	(_AC(1, UL) << _PAGE_SHIFT)
+#define _PAGE_MASK	(~(_PAGE_SIZE - 1))
+
 /* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT      12
-#define PAGE_SIZE	(_AC(1,UL) << PAGE_SHIFT)
-#define PAGE_MASK       (~(PAGE_SIZE-1))
+#define PAGE_SHIFT	_PAGE_SHIFT
+#define PAGE_SIZE	_PAGE_SIZE
+#define PAGE_MASK	_PAGE_MASK
 #define PAGE_DEFAULT_ACC	0
 #define PAGE_DEFAULT_KEY	(PAGE_DEFAULT_ACC << 4)
 
--- a/arch/s390/include/asm/pgalloc.h
+++ b/arch/s390/include/asm/pgalloc.h
@@ -15,6 +15,8 @@
 #include <linux/gfp.h>
 #include <linux/mm.h>
 
+#define CRST_ALLOC_ORDER 2
+
 unsigned long *crst_table_alloc(struct mm_struct *);
 void crst_table_free(struct mm_struct *, unsigned long *);
 
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -81,22 +81,6 @@ extern unsigned long zero_page_mask;
 #endif /* !__ASSEMBLY__ */
 
 /*
- * PMD_SHIFT determines the size of the area a second-level page
- * table can map
- * PGDIR_SHIFT determines what a third-level page table entry can map
- */
-#define PMD_SHIFT	20
-#define PUD_SHIFT	31
-#define PGDIR_SHIFT	42
-
-#define PMD_SIZE        (1UL << PMD_SHIFT)
-#define PMD_MASK        (~(PMD_SIZE-1))
-#define PUD_SIZE	(1UL << PUD_SHIFT)
-#define PUD_MASK	(~(PUD_SIZE-1))
-#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
-#define PGDIR_MASK	(~(PGDIR_SIZE-1))
-
-/*
  * entries per page directory level: the S390 is two-level, so
  * we don't really have any PMD directory physically.
  * for S390 segment-table entries are combined to one PGD
@@ -337,6 +321,45 @@ static inline int is_module_addr(void *a
 #define _SEGMENT_ENTRY_SOFT_DIRTY 0x0000 /* SW segment soft dirty bit */
 #endif
 
+#define _CRST_ENTRIES	2048	/* number of region/segment table entries */
+#define _PAGE_ENTRIES	256	/* number of page table entries	*/
+
+#define _CRST_TABLE_SIZE (_CRST_ENTRIES * 8)
+#define _PAGE_TABLE_SIZE (_PAGE_ENTRIES * 8)
+
+#define _REGION1_SHIFT	53
+#define _REGION2_SHIFT	42
+#define _REGION3_SHIFT	31
+#define _SEGMENT_SHIFT	20
+
+#define _REGION1_INDEX	(0x7ffUL << _REGION1_SHIFT)
+#define _REGION2_INDEX	(0x7ffUL << _REGION2_SHIFT)
+#define _REGION3_INDEX	(0x7ffUL << _REGION3_SHIFT)
+#define _SEGMENT_INDEX	(0x7ffUL << _SEGMENT_SHIFT)
+#define _PAGE_INDEX	(0xffUL  << _PAGE_SHIFT)
+
+#define _REGION1_SIZE	(1UL << _REGION1_SHIFT)
+#define _REGION2_SIZE	(1UL << _REGION2_SHIFT)
+#define _REGION3_SIZE	(1UL << _REGION3_SHIFT)
+#define _SEGMENT_SIZE	(1UL << _SEGMENT_SHIFT)
+
+#define _REGION1_MASK	(~(_REGION1_SIZE - 1))
+#define _REGION2_MASK	(~(_REGION2_SIZE - 1))
+#define _REGION3_MASK	(~(_REGION3_SIZE - 1))
+#define _SEGMENT_MASK	(~(_SEGMENT_SIZE - 1))
+
+#define PMD_SHIFT	_SEGMENT_SHIFT
+#define PUD_SHIFT	_REGION3_SHIFT
+#define PGDIR_SHIFT	_REGION2_SHIFT
+
+#define PMD_SIZE	_SEGMENT_SIZE
+#define PUD_SIZE	_REGION3_SIZE
+#define PGDIR_SIZE	_REGION2_SIZE
+
+#define PMD_MASK	_SEGMENT_MASK
+#define PUD_MASK	_REGION3_MASK
+#define PGDIR_MASK	_REGION2_MASK
+
 /*
  * Segment table and region3 table entry encoding
  * (R = read-only, I = invalid, y = young bit):