1133 строки
34 KiB
C
1133 строки
34 KiB
C
/*
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* include/asm-s390/pgtable.h
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*
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* S390 version
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* Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
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* Author(s): Hartmut Penner (hp@de.ibm.com)
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* Ulrich Weigand (weigand@de.ibm.com)
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* Martin Schwidefsky (schwidefsky@de.ibm.com)
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*
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* Derived from "include/asm-i386/pgtable.h"
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*/
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#ifndef _ASM_S390_PGTABLE_H
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#define _ASM_S390_PGTABLE_H
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/*
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* The Linux memory management assumes a three-level page table setup. For
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* s390 31 bit we "fold" the mid level into the top-level page table, so
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* that we physically have the same two-level page table as the s390 mmu
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* expects in 31 bit mode. For s390 64 bit we use three of the five levels
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* the hardware provides (region first and region second tables are not
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* used).
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*
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* The "pgd_xxx()" functions are trivial for a folded two-level
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* setup: the pgd is never bad, and a pmd always exists (as it's folded
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* into the pgd entry)
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*
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* This file contains the functions and defines necessary to modify and use
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* the S390 page table tree.
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*/
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#ifndef __ASSEMBLY__
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#include <linux/sched.h>
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#include <linux/mm_types.h>
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#include <asm/bitops.h>
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#include <asm/bug.h>
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#include <asm/processor.h>
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extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096)));
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extern void paging_init(void);
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extern void vmem_map_init(void);
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/*
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* The S390 doesn't have any external MMU info: the kernel page
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* tables contain all the necessary information.
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*/
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#define update_mmu_cache(vma, address, pte) do { } while (0)
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/*
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* ZERO_PAGE is a global shared page that is always zero: used
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* for zero-mapped memory areas etc..
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*/
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extern char empty_zero_page[PAGE_SIZE];
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#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
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#endif /* !__ASSEMBLY__ */
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/*
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* PMD_SHIFT determines the size of the area a second-level page
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* table can map
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* PGDIR_SHIFT determines what a third-level page table entry can map
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*/
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#ifndef __s390x__
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# define PMD_SHIFT 20
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# define PUD_SHIFT 20
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# define PGDIR_SHIFT 20
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#else /* __s390x__ */
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# define PMD_SHIFT 20
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# define PUD_SHIFT 31
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# define PGDIR_SHIFT 42
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#endif /* __s390x__ */
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#define PMD_SIZE (1UL << PMD_SHIFT)
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#define PMD_MASK (~(PMD_SIZE-1))
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#define PUD_SIZE (1UL << PUD_SHIFT)
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#define PUD_MASK (~(PUD_SIZE-1))
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#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
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#define PGDIR_MASK (~(PGDIR_SIZE-1))
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/*
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* entries per page directory level: the S390 is two-level, so
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* we don't really have any PMD directory physically.
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* for S390 segment-table entries are combined to one PGD
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* that leads to 1024 pte per pgd
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*/
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#define PTRS_PER_PTE 256
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#ifndef __s390x__
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#define PTRS_PER_PMD 1
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#define PTRS_PER_PUD 1
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#else /* __s390x__ */
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#define PTRS_PER_PMD 2048
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#define PTRS_PER_PUD 2048
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#endif /* __s390x__ */
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#define PTRS_PER_PGD 2048
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#define FIRST_USER_ADDRESS 0
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#define pte_ERROR(e) \
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printk("%s:%d: bad pte %p.\n", __FILE__, __LINE__, (void *) pte_val(e))
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#define pmd_ERROR(e) \
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printk("%s:%d: bad pmd %p.\n", __FILE__, __LINE__, (void *) pmd_val(e))
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#define pud_ERROR(e) \
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printk("%s:%d: bad pud %p.\n", __FILE__, __LINE__, (void *) pud_val(e))
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#define pgd_ERROR(e) \
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printk("%s:%d: bad pgd %p.\n", __FILE__, __LINE__, (void *) pgd_val(e))
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#ifndef __ASSEMBLY__
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/*
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* The vmalloc area will always be on the topmost area of the kernel
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* mapping. We reserve 96MB (31bit) / 1GB (64bit) for vmalloc,
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* which should be enough for any sane case.
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* By putting vmalloc at the top, we maximise the gap between physical
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* memory and vmalloc to catch misplaced memory accesses. As a side
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* effect, this also makes sure that 64 bit module code cannot be used
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* as system call address.
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*/
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#ifndef __s390x__
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#define VMALLOC_START 0x78000000UL
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#define VMALLOC_END 0x7e000000UL
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#define VMEM_MAP_END 0x80000000UL
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#else /* __s390x__ */
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#define VMALLOC_START 0x3e000000000UL
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#define VMALLOC_END 0x3e040000000UL
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#define VMEM_MAP_END 0x40000000000UL
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#endif /* __s390x__ */
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/*
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* VMEM_MAX_PHYS is the highest physical address that can be added to the 1:1
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* mapping. This needs to be calculated at compile time since the size of the
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* VMEM_MAP is static but the size of struct page can change.
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*/
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#define VMEM_MAX_PAGES ((VMEM_MAP_END - VMALLOC_END) / sizeof(struct page))
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#define VMEM_MAX_PFN min(VMALLOC_START >> PAGE_SHIFT, VMEM_MAX_PAGES)
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#define VMEM_MAX_PHYS ((VMEM_MAX_PFN << PAGE_SHIFT) & ~((16 << 20) - 1))
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#define vmemmap ((struct page *) VMALLOC_END)
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/*
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* A 31 bit pagetable entry of S390 has following format:
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* | PFRA | | OS |
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* 0 0IP0
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* 00000000001111111111222222222233
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* 01234567890123456789012345678901
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*
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* I Page-Invalid Bit: Page is not available for address-translation
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* P Page-Protection Bit: Store access not possible for page
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*
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* A 31 bit segmenttable entry of S390 has following format:
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* | P-table origin | |PTL
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* 0 IC
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* 00000000001111111111222222222233
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* 01234567890123456789012345678901
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*
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* I Segment-Invalid Bit: Segment is not available for address-translation
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* C Common-Segment Bit: Segment is not private (PoP 3-30)
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* PTL Page-Table-Length: Page-table length (PTL+1*16 entries -> up to 256)
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*
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* The 31 bit segmenttable origin of S390 has following format:
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*
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* |S-table origin | | STL |
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* X **GPS
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* 00000000001111111111222222222233
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* 01234567890123456789012345678901
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*
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* X Space-Switch event:
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* G Segment-Invalid Bit: *
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* P Private-Space Bit: Segment is not private (PoP 3-30)
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* S Storage-Alteration:
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* STL Segment-Table-Length: Segment-table length (STL+1*16 entries -> up to 2048)
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*
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* A 64 bit pagetable entry of S390 has following format:
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* | PFRA |0IP0| OS |
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* 0000000000111111111122222222223333333333444444444455555555556666
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* 0123456789012345678901234567890123456789012345678901234567890123
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*
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* I Page-Invalid Bit: Page is not available for address-translation
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* P Page-Protection Bit: Store access not possible for page
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*
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* A 64 bit segmenttable entry of S390 has following format:
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* | P-table origin | TT
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* 0000000000111111111122222222223333333333444444444455555555556666
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* 0123456789012345678901234567890123456789012345678901234567890123
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*
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* I Segment-Invalid Bit: Segment is not available for address-translation
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* C Common-Segment Bit: Segment is not private (PoP 3-30)
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* P Page-Protection Bit: Store access not possible for page
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* TT Type 00
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*
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* A 64 bit region table entry of S390 has following format:
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* | S-table origin | TF TTTL
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* 0000000000111111111122222222223333333333444444444455555555556666
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* 0123456789012345678901234567890123456789012345678901234567890123
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*
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* I Segment-Invalid Bit: Segment is not available for address-translation
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* TT Type 01
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* TF
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* TL Table length
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*
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* The 64 bit regiontable origin of S390 has following format:
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* | region table origon | DTTL
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* 0000000000111111111122222222223333333333444444444455555555556666
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* 0123456789012345678901234567890123456789012345678901234567890123
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*
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* X Space-Switch event:
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* G Segment-Invalid Bit:
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* P Private-Space Bit:
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* S Storage-Alteration:
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* R Real space
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* TL Table-Length:
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*
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* A storage key has the following format:
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* | ACC |F|R|C|0|
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* 0 3 4 5 6 7
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* ACC: access key
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* F : fetch protection bit
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* R : referenced bit
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* C : changed bit
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*/
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/* Hardware bits in the page table entry */
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#define _PAGE_RO 0x200 /* HW read-only bit */
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#define _PAGE_INVALID 0x400 /* HW invalid bit */
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/* Software bits in the page table entry */
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#define _PAGE_SWT 0x001 /* SW pte type bit t */
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#define _PAGE_SWX 0x002 /* SW pte type bit x */
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#define _PAGE_SPECIAL 0x004 /* SW associated with special page */
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#define __HAVE_ARCH_PTE_SPECIAL
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/* Set of bits not changed in pte_modify */
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#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_SPECIAL)
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/* Six different types of pages. */
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#define _PAGE_TYPE_EMPTY 0x400
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#define _PAGE_TYPE_NONE 0x401
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#define _PAGE_TYPE_SWAP 0x403
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#define _PAGE_TYPE_FILE 0x601 /* bit 0x002 is used for offset !! */
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#define _PAGE_TYPE_RO 0x200
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#define _PAGE_TYPE_RW 0x000
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#define _PAGE_TYPE_EX_RO 0x202
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#define _PAGE_TYPE_EX_RW 0x002
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/*
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* Only four types for huge pages, using the invalid bit and protection bit
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* of a segment table entry.
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*/
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#define _HPAGE_TYPE_EMPTY 0x020 /* _SEGMENT_ENTRY_INV */
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#define _HPAGE_TYPE_NONE 0x220
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#define _HPAGE_TYPE_RO 0x200 /* _SEGMENT_ENTRY_RO */
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#define _HPAGE_TYPE_RW 0x000
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/*
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* PTE type bits are rather complicated. handle_pte_fault uses pte_present,
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* pte_none and pte_file to find out the pte type WITHOUT holding the page
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* table lock. ptep_clear_flush on the other hand uses ptep_clear_flush to
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* invalidate a given pte. ipte sets the hw invalid bit and clears all tlbs
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* for the page. The page table entry is set to _PAGE_TYPE_EMPTY afterwards.
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* This change is done while holding the lock, but the intermediate step
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* of a previously valid pte with the hw invalid bit set can be observed by
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* handle_pte_fault. That makes it necessary that all valid pte types with
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* the hw invalid bit set must be distinguishable from the four pte types
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* empty, none, swap and file.
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*
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* irxt ipte irxt
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* _PAGE_TYPE_EMPTY 1000 -> 1000
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* _PAGE_TYPE_NONE 1001 -> 1001
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* _PAGE_TYPE_SWAP 1011 -> 1011
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* _PAGE_TYPE_FILE 11?1 -> 11?1
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* _PAGE_TYPE_RO 0100 -> 1100
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* _PAGE_TYPE_RW 0000 -> 1000
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* _PAGE_TYPE_EX_RO 0110 -> 1110
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* _PAGE_TYPE_EX_RW 0010 -> 1010
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*
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* pte_none is true for bits combinations 1000, 1010, 1100, 1110
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* pte_present is true for bits combinations 0000, 0010, 0100, 0110, 1001
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* pte_file is true for bits combinations 1101, 1111
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* swap pte is 1011 and 0001, 0011, 0101, 0111 are invalid.
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*/
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/* Page status table bits for virtualization */
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#define RCP_PCL_BIT 55
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#define RCP_HR_BIT 54
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#define RCP_HC_BIT 53
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#define RCP_GR_BIT 50
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#define RCP_GC_BIT 49
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/* User dirty bit for KVM's migration feature */
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#define KVM_UD_BIT 47
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#ifndef __s390x__
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/* Bits in the segment table address-space-control-element */
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#define _ASCE_SPACE_SWITCH 0x80000000UL /* space switch event */
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#define _ASCE_ORIGIN_MASK 0x7ffff000UL /* segment table origin */
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#define _ASCE_PRIVATE_SPACE 0x100 /* private space control */
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#define _ASCE_ALT_EVENT 0x80 /* storage alteration event control */
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#define _ASCE_TABLE_LENGTH 0x7f /* 128 x 64 entries = 8k */
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/* Bits in the segment table entry */
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#define _SEGMENT_ENTRY_ORIGIN 0x7fffffc0UL /* page table origin */
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#define _SEGMENT_ENTRY_INV 0x20 /* invalid segment table entry */
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#define _SEGMENT_ENTRY_COMMON 0x10 /* common segment bit */
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#define _SEGMENT_ENTRY_PTL 0x0f /* page table length */
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#define _SEGMENT_ENTRY (_SEGMENT_ENTRY_PTL)
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#define _SEGMENT_ENTRY_EMPTY (_SEGMENT_ENTRY_INV)
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#else /* __s390x__ */
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/* Bits in the segment/region table address-space-control-element */
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#define _ASCE_ORIGIN ~0xfffUL/* segment table origin */
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#define _ASCE_PRIVATE_SPACE 0x100 /* private space control */
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#define _ASCE_ALT_EVENT 0x80 /* storage alteration event control */
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#define _ASCE_SPACE_SWITCH 0x40 /* space switch event */
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#define _ASCE_REAL_SPACE 0x20 /* real space control */
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#define _ASCE_TYPE_MASK 0x0c /* asce table type mask */
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#define _ASCE_TYPE_REGION1 0x0c /* region first table type */
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#define _ASCE_TYPE_REGION2 0x08 /* region second table type */
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#define _ASCE_TYPE_REGION3 0x04 /* region third table type */
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#define _ASCE_TYPE_SEGMENT 0x00 /* segment table type */
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#define _ASCE_TABLE_LENGTH 0x03 /* region table length */
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/* Bits in the region table entry */
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#define _REGION_ENTRY_ORIGIN ~0xfffUL/* region/segment table origin */
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#define _REGION_ENTRY_INV 0x20 /* invalid region table entry */
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#define _REGION_ENTRY_TYPE_MASK 0x0c /* region/segment table type mask */
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#define _REGION_ENTRY_TYPE_R1 0x0c /* region first table type */
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#define _REGION_ENTRY_TYPE_R2 0x08 /* region second table type */
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#define _REGION_ENTRY_TYPE_R3 0x04 /* region third table type */
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#define _REGION_ENTRY_LENGTH 0x03 /* region third length */
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#define _REGION1_ENTRY (_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_LENGTH)
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#define _REGION1_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INV)
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#define _REGION2_ENTRY (_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_LENGTH)
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#define _REGION2_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INV)
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#define _REGION3_ENTRY (_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_LENGTH)
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#define _REGION3_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INV)
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/* Bits in the segment table entry */
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#define _SEGMENT_ENTRY_ORIGIN ~0x7ffUL/* segment table origin */
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#define _SEGMENT_ENTRY_RO 0x200 /* page protection bit */
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#define _SEGMENT_ENTRY_INV 0x20 /* invalid segment table entry */
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#define _SEGMENT_ENTRY (0)
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#define _SEGMENT_ENTRY_EMPTY (_SEGMENT_ENTRY_INV)
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#define _SEGMENT_ENTRY_LARGE 0x400 /* STE-format control, large page */
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#define _SEGMENT_ENTRY_CO 0x100 /* change-recording override */
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#endif /* __s390x__ */
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/*
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* A user page table pointer has the space-switch-event bit, the
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* private-space-control bit and the storage-alteration-event-control
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* bit set. A kernel page table pointer doesn't need them.
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*/
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#define _ASCE_USER_BITS (_ASCE_SPACE_SWITCH | _ASCE_PRIVATE_SPACE | \
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_ASCE_ALT_EVENT)
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/* Bits int the storage key */
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#define _PAGE_CHANGED 0x02 /* HW changed bit */
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#define _PAGE_REFERENCED 0x04 /* HW referenced bit */
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/*
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* Page protection definitions.
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*/
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#define PAGE_NONE __pgprot(_PAGE_TYPE_NONE)
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#define PAGE_RO __pgprot(_PAGE_TYPE_RO)
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#define PAGE_RW __pgprot(_PAGE_TYPE_RW)
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#define PAGE_EX_RO __pgprot(_PAGE_TYPE_EX_RO)
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#define PAGE_EX_RW __pgprot(_PAGE_TYPE_EX_RW)
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#define PAGE_KERNEL PAGE_RW
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#define PAGE_COPY PAGE_RO
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/*
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* Dependent on the EXEC_PROTECT option s390 can do execute protection.
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* Write permission always implies read permission. In theory with a
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* primary/secondary page table execute only can be implemented but
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* it would cost an additional bit in the pte to distinguish all the
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* different pte types. To avoid that execute permission currently
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* implies read permission as well.
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*/
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/*xwr*/
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#define __P000 PAGE_NONE
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#define __P001 PAGE_RO
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#define __P010 PAGE_RO
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#define __P011 PAGE_RO
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#define __P100 PAGE_EX_RO
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#define __P101 PAGE_EX_RO
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#define __P110 PAGE_EX_RO
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#define __P111 PAGE_EX_RO
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#define __S000 PAGE_NONE
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#define __S001 PAGE_RO
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#define __S010 PAGE_RW
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#define __S011 PAGE_RW
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#define __S100 PAGE_EX_RO
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#define __S101 PAGE_EX_RO
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#define __S110 PAGE_EX_RW
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#define __S111 PAGE_EX_RW
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#ifndef __s390x__
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# define PxD_SHADOW_SHIFT 1
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#else /* __s390x__ */
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# define PxD_SHADOW_SHIFT 2
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#endif /* __s390x__ */
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static inline void *get_shadow_table(void *table)
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{
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unsigned long addr, offset;
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struct page *page;
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addr = (unsigned long) table;
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offset = addr & ((PAGE_SIZE << PxD_SHADOW_SHIFT) - 1);
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page = virt_to_page((void *)(addr ^ offset));
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return (void *)(addr_t)(page->index ? (page->index | offset) : 0UL);
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}
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/*
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* Certain architectures need to do special things when PTEs
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* within a page table are directly modified. Thus, the following
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* hook is made available.
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*/
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static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
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pte_t *ptep, pte_t entry)
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{
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*ptep = entry;
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if (mm->context.noexec) {
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if (!(pte_val(entry) & _PAGE_INVALID) &&
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(pte_val(entry) & _PAGE_SWX))
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pte_val(entry) |= _PAGE_RO;
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else
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pte_val(entry) = _PAGE_TYPE_EMPTY;
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ptep[PTRS_PER_PTE] = entry;
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}
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}
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/*
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* pgd/pmd/pte query functions
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*/
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#ifndef __s390x__
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static inline int pgd_present(pgd_t pgd) { return 1; }
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static inline int pgd_none(pgd_t pgd) { return 0; }
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static inline int pgd_bad(pgd_t pgd) { return 0; }
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static inline int pud_present(pud_t pud) { return 1; }
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static inline int pud_none(pud_t pud) { return 0; }
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static inline int pud_bad(pud_t pud) { return 0; }
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#else /* __s390x__ */
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static inline int pgd_present(pgd_t pgd)
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{
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if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R2)
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return 1;
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return (pgd_val(pgd) & _REGION_ENTRY_ORIGIN) != 0UL;
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}
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static inline int pgd_none(pgd_t pgd)
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{
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if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R2)
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return 0;
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return (pgd_val(pgd) & _REGION_ENTRY_INV) != 0UL;
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}
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static inline int pgd_bad(pgd_t pgd)
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{
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/*
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* With dynamic page table levels the pgd can be a region table
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* entry or a segment table entry. Check for the bit that are
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* invalid for either table entry.
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*/
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unsigned long mask =
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~_SEGMENT_ENTRY_ORIGIN & ~_REGION_ENTRY_INV &
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~_REGION_ENTRY_TYPE_MASK & ~_REGION_ENTRY_LENGTH;
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return (pgd_val(pgd) & mask) != 0;
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}
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static inline int pud_present(pud_t pud)
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{
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if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
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return 1;
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return (pud_val(pud) & _REGION_ENTRY_ORIGIN) != 0UL;
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}
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static inline int pud_none(pud_t pud)
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{
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if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
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return 0;
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return (pud_val(pud) & _REGION_ENTRY_INV) != 0UL;
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}
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static inline int pud_bad(pud_t pud)
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{
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/*
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* With dynamic page table levels the pud can be a region table
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* entry or a segment table entry. Check for the bit that are
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* invalid for either table entry.
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*/
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unsigned long mask =
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~_SEGMENT_ENTRY_ORIGIN & ~_REGION_ENTRY_INV &
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~_REGION_ENTRY_TYPE_MASK & ~_REGION_ENTRY_LENGTH;
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return (pud_val(pud) & mask) != 0;
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}
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#endif /* __s390x__ */
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static inline int pmd_present(pmd_t pmd)
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{
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return (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN) != 0UL;
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}
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static inline int pmd_none(pmd_t pmd)
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{
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return (pmd_val(pmd) & _SEGMENT_ENTRY_INV) != 0UL;
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}
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static inline int pmd_bad(pmd_t pmd)
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{
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unsigned long mask = ~_SEGMENT_ENTRY_ORIGIN & ~_SEGMENT_ENTRY_INV;
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return (pmd_val(pmd) & mask) != _SEGMENT_ENTRY;
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}
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static inline int pte_none(pte_t pte)
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{
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return (pte_val(pte) & _PAGE_INVALID) && !(pte_val(pte) & _PAGE_SWT);
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}
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static inline int pte_present(pte_t pte)
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{
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unsigned long mask = _PAGE_RO | _PAGE_INVALID | _PAGE_SWT | _PAGE_SWX;
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return (pte_val(pte) & mask) == _PAGE_TYPE_NONE ||
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(!(pte_val(pte) & _PAGE_INVALID) &&
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!(pte_val(pte) & _PAGE_SWT));
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}
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static inline int pte_file(pte_t pte)
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{
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unsigned long mask = _PAGE_RO | _PAGE_INVALID | _PAGE_SWT;
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return (pte_val(pte) & mask) == _PAGE_TYPE_FILE;
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}
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static inline int pte_special(pte_t pte)
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{
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return (pte_val(pte) & _PAGE_SPECIAL);
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}
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#define __HAVE_ARCH_PTE_SAME
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#define pte_same(a,b) (pte_val(a) == pte_val(b))
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static inline void rcp_lock(pte_t *ptep)
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{
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#ifdef CONFIG_PGSTE
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unsigned long *pgste = (unsigned long *) (ptep + PTRS_PER_PTE);
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preempt_disable();
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while (test_and_set_bit(RCP_PCL_BIT, pgste))
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;
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#endif
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}
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static inline void rcp_unlock(pte_t *ptep)
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{
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#ifdef CONFIG_PGSTE
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unsigned long *pgste = (unsigned long *) (ptep + PTRS_PER_PTE);
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clear_bit(RCP_PCL_BIT, pgste);
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preempt_enable();
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#endif
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}
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/* forward declaration for SetPageUptodate in page-flags.h*/
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static inline void page_clear_dirty(struct page *page);
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#include <linux/page-flags.h>
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static inline void ptep_rcp_copy(pte_t *ptep)
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{
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#ifdef CONFIG_PGSTE
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struct page *page = virt_to_page(pte_val(*ptep));
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unsigned int skey;
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unsigned long *pgste = (unsigned long *) (ptep + PTRS_PER_PTE);
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skey = page_get_storage_key(page_to_phys(page));
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if (skey & _PAGE_CHANGED) {
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set_bit_simple(RCP_GC_BIT, pgste);
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set_bit_simple(KVM_UD_BIT, pgste);
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}
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if (skey & _PAGE_REFERENCED)
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set_bit_simple(RCP_GR_BIT, pgste);
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if (test_and_clear_bit_simple(RCP_HC_BIT, pgste)) {
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SetPageDirty(page);
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set_bit_simple(KVM_UD_BIT, pgste);
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}
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if (test_and_clear_bit_simple(RCP_HR_BIT, pgste))
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SetPageReferenced(page);
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#endif
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}
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/*
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* query functions pte_write/pte_dirty/pte_young only work if
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* pte_present() is true. Undefined behaviour if not..
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*/
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static inline int pte_write(pte_t pte)
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{
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return (pte_val(pte) & _PAGE_RO) == 0;
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}
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static inline int pte_dirty(pte_t pte)
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{
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/* A pte is neither clean nor dirty on s/390. The dirty bit
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* is in the storage key. See page_test_and_clear_dirty for
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* details.
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*/
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return 0;
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}
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static inline int pte_young(pte_t pte)
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{
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/* A pte is neither young nor old on s/390. The young bit
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* is in the storage key. See page_test_and_clear_young for
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* details.
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*/
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return 0;
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}
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/*
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* pgd/pmd/pte modification functions
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*/
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#ifndef __s390x__
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#define pgd_clear(pgd) do { } while (0)
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#define pud_clear(pud) do { } while (0)
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#else /* __s390x__ */
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static inline void pgd_clear_kernel(pgd_t * pgd)
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{
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if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R2)
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pgd_val(*pgd) = _REGION2_ENTRY_EMPTY;
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}
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static inline void pgd_clear(pgd_t * pgd)
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{
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pgd_t *shadow = get_shadow_table(pgd);
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pgd_clear_kernel(pgd);
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if (shadow)
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pgd_clear_kernel(shadow);
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}
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static inline void pud_clear_kernel(pud_t *pud)
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{
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if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
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pud_val(*pud) = _REGION3_ENTRY_EMPTY;
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}
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static inline void pud_clear(pud_t *pud)
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{
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pud_t *shadow = get_shadow_table(pud);
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pud_clear_kernel(pud);
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if (shadow)
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pud_clear_kernel(shadow);
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}
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#endif /* __s390x__ */
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static inline void pmd_clear_kernel(pmd_t * pmdp)
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{
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pmd_val(*pmdp) = _SEGMENT_ENTRY_EMPTY;
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}
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static inline void pmd_clear(pmd_t *pmd)
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{
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pmd_t *shadow = get_shadow_table(pmd);
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pmd_clear_kernel(pmd);
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if (shadow)
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pmd_clear_kernel(shadow);
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}
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static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
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{
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pte_val(*ptep) = _PAGE_TYPE_EMPTY;
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if (mm->context.noexec)
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pte_val(ptep[PTRS_PER_PTE]) = _PAGE_TYPE_EMPTY;
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}
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/*
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* The following pte modification functions only work if
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* pte_present() is true. Undefined behaviour if not..
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*/
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static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
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{
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pte_val(pte) &= _PAGE_CHG_MASK;
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pte_val(pte) |= pgprot_val(newprot);
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return pte;
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}
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static inline pte_t pte_wrprotect(pte_t pte)
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{
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/* Do not clobber _PAGE_TYPE_NONE pages! */
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if (!(pte_val(pte) & _PAGE_INVALID))
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pte_val(pte) |= _PAGE_RO;
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return pte;
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}
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static inline pte_t pte_mkwrite(pte_t pte)
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{
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pte_val(pte) &= ~_PAGE_RO;
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return pte;
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}
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static inline pte_t pte_mkclean(pte_t pte)
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{
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/* The only user of pte_mkclean is the fork() code.
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We must *not* clear the *physical* page dirty bit
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just because fork() wants to clear the dirty bit in
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*one* of the page's mappings. So we just do nothing. */
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return pte;
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}
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static inline pte_t pte_mkdirty(pte_t pte)
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{
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/* We do not explicitly set the dirty bit because the
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* sske instruction is slow. It is faster to let the
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* next instruction set the dirty bit.
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*/
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return pte;
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}
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static inline pte_t pte_mkold(pte_t pte)
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{
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/* S/390 doesn't keep its dirty/referenced bit in the pte.
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* There is no point in clearing the real referenced bit.
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*/
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return pte;
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}
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static inline pte_t pte_mkyoung(pte_t pte)
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{
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/* S/390 doesn't keep its dirty/referenced bit in the pte.
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* There is no point in setting the real referenced bit.
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*/
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return pte;
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}
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static inline pte_t pte_mkspecial(pte_t pte)
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{
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pte_val(pte) |= _PAGE_SPECIAL;
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return pte;
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}
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#ifdef CONFIG_PGSTE
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/*
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* Get (and clear) the user dirty bit for a PTE.
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*/
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static inline int kvm_s390_test_and_clear_page_dirty(struct mm_struct *mm,
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pte_t *ptep)
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{
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int dirty;
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unsigned long *pgste;
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struct page *page;
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unsigned int skey;
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if (!mm->context.has_pgste)
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return -EINVAL;
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rcp_lock(ptep);
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pgste = (unsigned long *) (ptep + PTRS_PER_PTE);
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page = virt_to_page(pte_val(*ptep));
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skey = page_get_storage_key(page_to_phys(page));
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if (skey & _PAGE_CHANGED) {
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set_bit_simple(RCP_GC_BIT, pgste);
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set_bit_simple(KVM_UD_BIT, pgste);
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}
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if (test_and_clear_bit_simple(RCP_HC_BIT, pgste)) {
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SetPageDirty(page);
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set_bit_simple(KVM_UD_BIT, pgste);
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}
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dirty = test_and_clear_bit_simple(KVM_UD_BIT, pgste);
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if (skey & _PAGE_CHANGED)
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page_clear_dirty(page);
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rcp_unlock(ptep);
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return dirty;
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}
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#endif
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#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
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static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
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unsigned long addr, pte_t *ptep)
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{
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#ifdef CONFIG_PGSTE
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unsigned long physpage;
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int young;
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unsigned long *pgste;
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if (!vma->vm_mm->context.has_pgste)
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return 0;
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physpage = pte_val(*ptep) & PAGE_MASK;
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pgste = (unsigned long *) (ptep + PTRS_PER_PTE);
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young = ((page_get_storage_key(physpage) & _PAGE_REFERENCED) != 0);
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rcp_lock(ptep);
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if (young)
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set_bit_simple(RCP_GR_BIT, pgste);
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young |= test_and_clear_bit_simple(RCP_HR_BIT, pgste);
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rcp_unlock(ptep);
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return young;
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#endif
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return 0;
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}
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#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
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static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
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unsigned long address, pte_t *ptep)
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{
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/* No need to flush TLB
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* On s390 reference bits are in storage key and never in TLB
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* With virtualization we handle the reference bit, without we
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* we can simply return */
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#ifdef CONFIG_PGSTE
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return ptep_test_and_clear_young(vma, address, ptep);
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#endif
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return 0;
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}
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static inline void __ptep_ipte(unsigned long address, pte_t *ptep)
|
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{
|
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if (!(pte_val(*ptep) & _PAGE_INVALID)) {
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#ifndef __s390x__
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/* pto must point to the start of the segment table */
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pte_t *pto = (pte_t *) (((unsigned long) ptep) & 0x7ffffc00);
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#else
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/* ipte in zarch mode can do the math */
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pte_t *pto = ptep;
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#endif
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asm volatile(
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" ipte %2,%3"
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: "=m" (*ptep) : "m" (*ptep),
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"a" (pto), "a" (address));
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}
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}
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static inline void ptep_invalidate(struct mm_struct *mm,
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unsigned long address, pte_t *ptep)
|
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{
|
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if (mm->context.has_pgste) {
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rcp_lock(ptep);
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__ptep_ipte(address, ptep);
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ptep_rcp_copy(ptep);
|
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pte_val(*ptep) = _PAGE_TYPE_EMPTY;
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rcp_unlock(ptep);
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return;
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}
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__ptep_ipte(address, ptep);
|
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pte_val(*ptep) = _PAGE_TYPE_EMPTY;
|
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if (mm->context.noexec) {
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__ptep_ipte(address, ptep + PTRS_PER_PTE);
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pte_val(*(ptep + PTRS_PER_PTE)) = _PAGE_TYPE_EMPTY;
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}
|
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}
|
|
|
|
/*
|
|
* This is hard to understand. ptep_get_and_clear and ptep_clear_flush
|
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* both clear the TLB for the unmapped pte. The reason is that
|
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* ptep_get_and_clear is used in common code (e.g. change_pte_range)
|
|
* to modify an active pte. The sequence is
|
|
* 1) ptep_get_and_clear
|
|
* 2) set_pte_at
|
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* 3) flush_tlb_range
|
|
* On s390 the tlb needs to get flushed with the modification of the pte
|
|
* if the pte is active. The only way how this can be implemented is to
|
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* have ptep_get_and_clear do the tlb flush. In exchange flush_tlb_range
|
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* is a nop.
|
|
*/
|
|
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
|
|
#define ptep_get_and_clear(__mm, __address, __ptep) \
|
|
({ \
|
|
pte_t __pte = *(__ptep); \
|
|
if (atomic_read(&(__mm)->mm_users) > 1 || \
|
|
(__mm) != current->active_mm) \
|
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ptep_invalidate(__mm, __address, __ptep); \
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else \
|
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pte_clear((__mm), (__address), (__ptep)); \
|
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__pte; \
|
|
})
|
|
|
|
#define __HAVE_ARCH_PTEP_CLEAR_FLUSH
|
|
static inline pte_t ptep_clear_flush(struct vm_area_struct *vma,
|
|
unsigned long address, pte_t *ptep)
|
|
{
|
|
pte_t pte = *ptep;
|
|
ptep_invalidate(vma->vm_mm, address, ptep);
|
|
return pte;
|
|
}
|
|
|
|
/*
|
|
* The batched pte unmap code uses ptep_get_and_clear_full to clear the
|
|
* ptes. Here an optimization is possible. tlb_gather_mmu flushes all
|
|
* tlbs of an mm if it can guarantee that the ptes of the mm_struct
|
|
* cannot be accessed while the batched unmap is running. In this case
|
|
* full==1 and a simple pte_clear is enough. See tlb.h.
|
|
*/
|
|
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
|
|
static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
|
|
unsigned long addr,
|
|
pte_t *ptep, int full)
|
|
{
|
|
pte_t pte = *ptep;
|
|
|
|
if (full)
|
|
pte_clear(mm, addr, ptep);
|
|
else
|
|
ptep_invalidate(mm, addr, ptep);
|
|
return pte;
|
|
}
|
|
|
|
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
|
|
#define ptep_set_wrprotect(__mm, __addr, __ptep) \
|
|
({ \
|
|
pte_t __pte = *(__ptep); \
|
|
if (pte_write(__pte)) { \
|
|
if (atomic_read(&(__mm)->mm_users) > 1 || \
|
|
(__mm) != current->active_mm) \
|
|
ptep_invalidate(__mm, __addr, __ptep); \
|
|
set_pte_at(__mm, __addr, __ptep, pte_wrprotect(__pte)); \
|
|
} \
|
|
})
|
|
|
|
#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
|
|
#define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __dirty) \
|
|
({ \
|
|
int __changed = !pte_same(*(__ptep), __entry); \
|
|
if (__changed) { \
|
|
ptep_invalidate((__vma)->vm_mm, __addr, __ptep); \
|
|
set_pte_at((__vma)->vm_mm, __addr, __ptep, __entry); \
|
|
} \
|
|
__changed; \
|
|
})
|
|
|
|
/*
|
|
* Test and clear dirty bit in storage key.
|
|
* We can't clear the changed bit atomically. This is a potential
|
|
* race against modification of the referenced bit. This function
|
|
* should therefore only be called if it is not mapped in any
|
|
* address space.
|
|
*/
|
|
#define __HAVE_ARCH_PAGE_TEST_DIRTY
|
|
static inline int page_test_dirty(struct page *page)
|
|
{
|
|
return (page_get_storage_key(page_to_phys(page)) & _PAGE_CHANGED) != 0;
|
|
}
|
|
|
|
#define __HAVE_ARCH_PAGE_CLEAR_DIRTY
|
|
static inline void page_clear_dirty(struct page *page)
|
|
{
|
|
page_set_storage_key(page_to_phys(page), PAGE_DEFAULT_KEY);
|
|
}
|
|
|
|
/*
|
|
* Test and clear referenced bit in storage key.
|
|
*/
|
|
#define __HAVE_ARCH_PAGE_TEST_AND_CLEAR_YOUNG
|
|
static inline int page_test_and_clear_young(struct page *page)
|
|
{
|
|
unsigned long physpage = page_to_phys(page);
|
|
int ccode;
|
|
|
|
asm volatile(
|
|
" rrbe 0,%1\n"
|
|
" ipm %0\n"
|
|
" srl %0,28\n"
|
|
: "=d" (ccode) : "a" (physpage) : "cc" );
|
|
return ccode & 2;
|
|
}
|
|
|
|
/*
|
|
* Conversion functions: convert a page and protection to a page entry,
|
|
* and a page entry and page directory to the page they refer to.
|
|
*/
|
|
static inline pte_t mk_pte_phys(unsigned long physpage, pgprot_t pgprot)
|
|
{
|
|
pte_t __pte;
|
|
pte_val(__pte) = physpage + pgprot_val(pgprot);
|
|
return __pte;
|
|
}
|
|
|
|
static inline pte_t mk_pte(struct page *page, pgprot_t pgprot)
|
|
{
|
|
unsigned long physpage = page_to_phys(page);
|
|
|
|
return mk_pte_phys(physpage, pgprot);
|
|
}
|
|
|
|
#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
|
|
#define pud_index(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
|
|
#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
|
|
#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
|
|
|
|
#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
|
|
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
|
|
|
|
#ifndef __s390x__
|
|
|
|
#define pmd_deref(pmd) (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN)
|
|
#define pud_deref(pmd) ({ BUG(); 0UL; })
|
|
#define pgd_deref(pmd) ({ BUG(); 0UL; })
|
|
|
|
#define pud_offset(pgd, address) ((pud_t *) pgd)
|
|
#define pmd_offset(pud, address) ((pmd_t *) pud + pmd_index(address))
|
|
|
|
#else /* __s390x__ */
|
|
|
|
#define pmd_deref(pmd) (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN)
|
|
#define pud_deref(pud) (pud_val(pud) & _REGION_ENTRY_ORIGIN)
|
|
#define pgd_deref(pgd) (pgd_val(pgd) & _REGION_ENTRY_ORIGIN)
|
|
|
|
static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
|
|
{
|
|
pud_t *pud = (pud_t *) pgd;
|
|
if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R2)
|
|
pud = (pud_t *) pgd_deref(*pgd);
|
|
return pud + pud_index(address);
|
|
}
|
|
|
|
static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
|
|
{
|
|
pmd_t *pmd = (pmd_t *) pud;
|
|
if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
|
|
pmd = (pmd_t *) pud_deref(*pud);
|
|
return pmd + pmd_index(address);
|
|
}
|
|
|
|
#endif /* __s390x__ */
|
|
|
|
#define pfn_pte(pfn,pgprot) mk_pte_phys(__pa((pfn) << PAGE_SHIFT),(pgprot))
|
|
#define pte_pfn(x) (pte_val(x) >> PAGE_SHIFT)
|
|
#define pte_page(x) pfn_to_page(pte_pfn(x))
|
|
|
|
#define pmd_page(pmd) pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)
|
|
|
|
/* Find an entry in the lowest level page table.. */
|
|
#define pte_offset(pmd, addr) ((pte_t *) pmd_deref(*(pmd)) + pte_index(addr))
|
|
#define pte_offset_kernel(pmd, address) pte_offset(pmd,address)
|
|
#define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
|
|
#define pte_offset_map_nested(pmd, address) pte_offset_kernel(pmd, address)
|
|
#define pte_unmap(pte) do { } while (0)
|
|
#define pte_unmap_nested(pte) do { } while (0)
|
|
|
|
/*
|
|
* 31 bit swap entry format:
|
|
* A page-table entry has some bits we have to treat in a special way.
|
|
* Bits 0, 20 and bit 23 have to be zero, otherwise an specification
|
|
* exception will occur instead of a page translation exception. The
|
|
* specifiation exception has the bad habit not to store necessary
|
|
* information in the lowcore.
|
|
* Bit 21 and bit 22 are the page invalid bit and the page protection
|
|
* bit. We set both to indicate a swapped page.
|
|
* Bit 30 and 31 are used to distinguish the different page types. For
|
|
* a swapped page these bits need to be zero.
|
|
* This leaves the bits 1-19 and bits 24-29 to store type and offset.
|
|
* We use the 5 bits from 25-29 for the type and the 20 bits from 1-19
|
|
* plus 24 for the offset.
|
|
* 0| offset |0110|o|type |00|
|
|
* 0 0000000001111111111 2222 2 22222 33
|
|
* 0 1234567890123456789 0123 4 56789 01
|
|
*
|
|
* 64 bit swap entry format:
|
|
* A page-table entry has some bits we have to treat in a special way.
|
|
* Bits 52 and bit 55 have to be zero, otherwise an specification
|
|
* exception will occur instead of a page translation exception. The
|
|
* specifiation exception has the bad habit not to store necessary
|
|
* information in the lowcore.
|
|
* Bit 53 and bit 54 are the page invalid bit and the page protection
|
|
* bit. We set both to indicate a swapped page.
|
|
* Bit 62 and 63 are used to distinguish the different page types. For
|
|
* a swapped page these bits need to be zero.
|
|
* This leaves the bits 0-51 and bits 56-61 to store type and offset.
|
|
* We use the 5 bits from 57-61 for the type and the 53 bits from 0-51
|
|
* plus 56 for the offset.
|
|
* | offset |0110|o|type |00|
|
|
* 0000000000111111111122222222223333333333444444444455 5555 5 55566 66
|
|
* 0123456789012345678901234567890123456789012345678901 2345 6 78901 23
|
|
*/
|
|
#ifndef __s390x__
|
|
#define __SWP_OFFSET_MASK (~0UL >> 12)
|
|
#else
|
|
#define __SWP_OFFSET_MASK (~0UL >> 11)
|
|
#endif
|
|
static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
|
|
{
|
|
pte_t pte;
|
|
offset &= __SWP_OFFSET_MASK;
|
|
pte_val(pte) = _PAGE_TYPE_SWAP | ((type & 0x1f) << 2) |
|
|
((offset & 1UL) << 7) | ((offset & ~1UL) << 11);
|
|
return pte;
|
|
}
|
|
|
|
#define __swp_type(entry) (((entry).val >> 2) & 0x1f)
|
|
#define __swp_offset(entry) (((entry).val >> 11) | (((entry).val >> 7) & 1))
|
|
#define __swp_entry(type,offset) ((swp_entry_t) { pte_val(mk_swap_pte((type),(offset))) })
|
|
|
|
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
|
|
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
|
|
|
|
#ifndef __s390x__
|
|
# define PTE_FILE_MAX_BITS 26
|
|
#else /* __s390x__ */
|
|
# define PTE_FILE_MAX_BITS 59
|
|
#endif /* __s390x__ */
|
|
|
|
#define pte_to_pgoff(__pte) \
|
|
((((__pte).pte >> 12) << 7) + (((__pte).pte >> 1) & 0x7f))
|
|
|
|
#define pgoff_to_pte(__off) \
|
|
((pte_t) { ((((__off) & 0x7f) << 1) + (((__off) >> 7) << 12)) \
|
|
| _PAGE_TYPE_FILE })
|
|
|
|
#endif /* !__ASSEMBLY__ */
|
|
|
|
#define kern_addr_valid(addr) (1)
|
|
|
|
extern int vmem_add_mapping(unsigned long start, unsigned long size);
|
|
extern int vmem_remove_mapping(unsigned long start, unsigned long size);
|
|
extern int s390_enable_sie(void);
|
|
|
|
/*
|
|
* No page table caches to initialise
|
|
*/
|
|
#define pgtable_cache_init() do { } while (0)
|
|
|
|
#include <asm-generic/pgtable.h>
|
|
|
|
#endif /* _S390_PAGE_H */
|