s390/mm: remove and correct comments within pgtable.h

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>
This commit is contained in:
Heiko Carstens 2017-06-14 08:57:24 +02:00 коммит произвёл Martin Schwidefsky
Родитель 810fa7efe0
Коммит 8457d7754b
1 изменённых файлов: 4 добавлений и 27 удалений

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@ -11,18 +11,6 @@
#ifndef _ASM_S390_PGTABLE_H
#define _ASM_S390_PGTABLE_H
/*
* The Linux memory management assumes a three-level page table setup.
* For s390 64 bit we use up to four of the five levels the hardware
* provides (region first tables are not used).
*
* The "pgd_xxx()" functions are trivial for a folded two-level
* setup: the pgd is never bad, and a pmd always exists (as it's folded
* into the pgd entry)
*
* This file contains the functions and defines necessary to modify and use
* the S390 page table tree.
*/
#ifndef __ASSEMBLY__
#include <linux/sched.h>
#include <linux/mm_types.h>
@ -79,11 +67,6 @@ extern unsigned long zero_page_mask;
/* TODO: s390 cannot support io_remap_pfn_range... */
#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 P4D_SHIFT 42
@ -98,12 +81,6 @@ extern unsigned long zero_page_mask;
#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
* that leads to 1024 pte per pgd
*/
#define PTRS_PER_PTE 256
#define PTRS_PER_PMD 2048
#define PTRS_PER_PUD 2048
@ -269,7 +246,7 @@ static inline int is_module_addr(void *addr)
*/
/* Bits in the segment/region table address-space-control-element */
#define _ASCE_ORIGIN ~0xfffUL/* segment table origin */
#define _ASCE_ORIGIN ~0xfffUL/* region/segment table origin */
#define _ASCE_PRIVATE_SPACE 0x100 /* private space control */
#define _ASCE_ALT_EVENT 0x80 /* storage alteration event control */
#define _ASCE_SPACE_SWITCH 0x40 /* space switch event */
@ -320,9 +297,9 @@ static inline int is_module_addr(void *addr)
#define _SEGMENT_ENTRY_BITS 0xfffffffffffffe33UL
#define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff0ff33UL
#define _SEGMENT_ENTRY_ORIGIN_LARGE ~0xfffffUL /* large page address */
#define _SEGMENT_ENTRY_ORIGIN ~0x7ffUL/* segment table origin */
#define _SEGMENT_ENTRY_PROTECT 0x200 /* page protection bit */
#define _SEGMENT_ENTRY_NOEXEC 0x100 /* region no-execute bit */
#define _SEGMENT_ENTRY_ORIGIN ~0x7ffUL/* page table origin */
#define _SEGMENT_ENTRY_PROTECT 0x200 /* segment protection bit */
#define _SEGMENT_ENTRY_NOEXEC 0x100 /* segment no-execute bit */
#define _SEGMENT_ENTRY_INVALID 0x20 /* invalid segment table entry */
#define _SEGMENT_ENTRY (0)