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Diffstat (limited to 'include/asm-s390/pgtable.h')
| -rw-r--r-- | include/asm-s390/pgtable.h | 813 |
1 files changed, 813 insertions, 0 deletions
diff --git a/include/asm-s390/pgtable.h b/include/asm-s390/pgtable.h new file mode 100644 index 000000000000..1633cb75f057 --- /dev/null +++ b/include/asm-s390/pgtable.h @@ -0,0 +1,813 @@ +/* + * include/asm-s390/pgtable.h + * + * S390 version + * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation + * Author(s): Hartmut Penner (hp@de.ibm.com) + * Ulrich Weigand (weigand@de.ibm.com) + * Martin Schwidefsky (schwidefsky@de.ibm.com) + * + * Derived from "include/asm-i386/pgtable.h" + */ + +#ifndef _ASM_S390_PGTABLE_H +#define _ASM_S390_PGTABLE_H + +#include <asm-generic/4level-fixup.h> + +/* + * The Linux memory management assumes a three-level page table setup. For + * s390 31 bit we "fold" the mid level into the top-level page table, so + * that we physically have the same two-level page table as the s390 mmu + * expects in 31 bit mode. For s390 64 bit we use three of the five levels + * the hardware provides (region first and region second 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 <asm/bug.h> +#include <asm/processor.h> +#include <linux/threads.h> + +struct vm_area_struct; /* forward declaration (include/linux/mm.h) */ + +extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096))); +extern void paging_init(void); + +/* + * The S390 doesn't have any external MMU info: the kernel page + * tables contain all the necessary information. + */ +#define update_mmu_cache(vma, address, pte) do { } while (0) + +/* + * ZERO_PAGE is a global shared page that is always zero: used + * for zero-mapped memory areas etc.. + */ +extern char empty_zero_page[PAGE_SIZE]; +#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) +#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 + */ +#ifndef __s390x__ +# define PMD_SHIFT 22 +# define PGDIR_SHIFT 22 +#else /* __s390x__ */ +# define PMD_SHIFT 21 +# define PGDIR_SHIFT 31 +#endif /* __s390x__ */ + +#define PMD_SIZE (1UL << PMD_SHIFT) +#define PMD_MASK (~(PMD_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 + * that leads to 1024 pte per pgd + */ +#ifndef __s390x__ +# define PTRS_PER_PTE 1024 +# define PTRS_PER_PMD 1 +# define PTRS_PER_PGD 512 +#else /* __s390x__ */ +# define PTRS_PER_PTE 512 +# define PTRS_PER_PMD 1024 +# define PTRS_PER_PGD 2048 +#endif /* __s390x__ */ + +/* + * pgd entries used up by user/kernel: + */ +#ifndef __s390x__ +# define USER_PTRS_PER_PGD 512 +# define USER_PGD_PTRS 512 +# define KERNEL_PGD_PTRS 512 +# define FIRST_USER_PGD_NR 0 +#else /* __s390x__ */ +# define USER_PTRS_PER_PGD 2048 +# define USER_PGD_PTRS 2048 +# define KERNEL_PGD_PTRS 2048 +# define FIRST_USER_PGD_NR 0 +#endif /* __s390x__ */ + +#define pte_ERROR(e) \ + printk("%s:%d: bad pte %p.\n", __FILE__, __LINE__, (void *) pte_val(e)) +#define pmd_ERROR(e) \ + printk("%s:%d: bad pmd %p.\n", __FILE__, __LINE__, (void *) pmd_val(e)) +#define pgd_ERROR(e) \ + printk("%s:%d: bad pgd %p.\n", __FILE__, __LINE__, (void *) pgd_val(e)) + +#ifndef __ASSEMBLY__ +/* + * Just any arbitrary offset to the start of the vmalloc VM area: the + * current 8MB value just means that there will be a 8MB "hole" after the + * physical memory until the kernel virtual memory starts. That means that + * any out-of-bounds memory accesses will hopefully be caught. + * The vmalloc() routines leaves a hole of 4kB between each vmalloced + * area for the same reason. ;) + */ +#define VMALLOC_OFFSET (8*1024*1024) +#define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) \ + & ~(VMALLOC_OFFSET-1)) +#ifndef __s390x__ +# define VMALLOC_END (0x7fffffffL) +#else /* __s390x__ */ +# define VMALLOC_END (0x40000000000L) +#endif /* __s390x__ */ + + +/* + * A 31 bit pagetable entry of S390 has following format: + * | PFRA | | OS | + * 0 0IP0 + * 00000000001111111111222222222233 + * 01234567890123456789012345678901 + * + * I Page-Invalid Bit: Page is not available for address-translation + * P Page-Protection Bit: Store access not possible for page + * + * A 31 bit segmenttable entry of S390 has following format: + * | P-table origin | |PTL + * 0 IC + * 00000000001111111111222222222233 + * 01234567890123456789012345678901 + * + * I Segment-Invalid Bit: Segment is not available for address-translation + * C Common-Segment Bit: Segment is not private (PoP 3-30) + * PTL Page-Table-Length: Page-table length (PTL+1*16 entries -> up to 256) + * + * The 31 bit segmenttable origin of S390 has following format: + * + * |S-table origin | | STL | + * X **GPS + * 00000000001111111111222222222233 + * 01234567890123456789012345678901 + * + * X Space-Switch event: + * G Segment-Invalid Bit: * + * P Private-Space Bit: Segment is not private (PoP 3-30) + * S Storage-Alteration: + * STL Segment-Table-Length: Segment-table length (STL+1*16 entries -> up to 2048) + * + * A 64 bit pagetable entry of S390 has following format: + * | PFRA |0IP0| OS | + * 0000000000111111111122222222223333333333444444444455555555556666 + * 0123456789012345678901234567890123456789012345678901234567890123 + * + * I Page-Invalid Bit: Page is not available for address-translation + * P Page-Protection Bit: Store access not possible for page + * + * A 64 bit segmenttable entry of S390 has following format: + * | P-table origin | TT + * 0000000000111111111122222222223333333333444444444455555555556666 + * 0123456789012345678901234567890123456789012345678901234567890123 + * + * I Segment-Invalid Bit: Segment is not available for address-translation + * C Common-Segment Bit: Segment is not private (PoP 3-30) + * P Page-Protection Bit: Store access not possible for page + * TT Type 00 + * + * A 64 bit region table entry of S390 has following format: + * | S-table origin | TF TTTL + * 0000000000111111111122222222223333333333444444444455555555556666 + * 0123456789012345678901234567890123456789012345678901234567890123 + * + * I Segment-Invalid Bit: Segment is not available for address-translation + * TT Type 01 + * TF + * TL Table lenght + * + * The 64 bit regiontable origin of S390 has following format: + * | region table origon | DTTL + * 0000000000111111111122222222223333333333444444444455555555556666 + * 0123456789012345678901234567890123456789012345678901234567890123 + * + * X Space-Switch event: + * G Segment-Invalid Bit: + * P Private-Space Bit: + * S Storage-Alteration: + * R Real space + * TL Table-Length: + * + * A storage key has the following format: + * | ACC |F|R|C|0| + * 0 3 4 5 6 7 + * ACC: access key + * F : fetch protection bit + * R : referenced bit + * C : changed bit + */ + +/* Hardware bits in the page table entry */ +#define _PAGE_RO 0x200 /* HW read-only */ +#define _PAGE_INVALID 0x400 /* HW invalid */ + +/* Mask and four different kinds of invalid pages. */ +#define _PAGE_INVALID_MASK 0x601 +#define _PAGE_INVALID_EMPTY 0x400 +#define _PAGE_INVALID_NONE 0x401 +#define _PAGE_INVALID_SWAP 0x600 +#define _PAGE_INVALID_FILE 0x601 + +#ifndef __s390x__ + +/* Bits in the segment table entry */ +#define _PAGE_TABLE_LEN 0xf /* only full page-tables */ +#define _PAGE_TABLE_COM 0x10 /* common page-table */ +#define _PAGE_TABLE_INV 0x20 /* invalid page-table */ +#define _SEG_PRESENT 0x001 /* Software (overlap with PTL) */ + +/* Bits int the storage key */ +#define _PAGE_CHANGED 0x02 /* HW changed bit */ +#define _PAGE_REFERENCED 0x04 /* HW referenced bit */ + +#define _USER_SEG_TABLE_LEN 0x7f /* user-segment-table up to 2 GB */ +#define _KERNEL_SEG_TABLE_LEN 0x7f /* kernel-segment-table up to 2 GB */ + +/* + * User and Kernel pagetables are identical + */ +#define _PAGE_TABLE _PAGE_TABLE_LEN +#define _KERNPG_TABLE _PAGE_TABLE_LEN + +/* + * The Kernel segment-tables includes the User segment-table + */ + +#define _SEGMENT_TABLE (_USER_SEG_TABLE_LEN|0x80000000|0x100) +#define _KERNSEG_TABLE _KERNEL_SEG_TABLE_LEN + +#define USER_STD_MASK 0x00000080UL + +#else /* __s390x__ */ + +/* Bits in the segment table entry */ +#define _PMD_ENTRY_INV 0x20 /* invalid segment table entry */ +#define _PMD_ENTRY 0x00 + +/* Bits in the region third table entry */ +#define _PGD_ENTRY_INV 0x20 /* invalid region table entry */ +#define _PGD_ENTRY 0x07 + +/* + * User and kernel page directory + */ +#define _REGION_THIRD 0x4 +#define _REGION_THIRD_LEN 0x3 +#define _REGION_TABLE (_REGION_THIRD|_REGION_THIRD_LEN|0x40|0x100) +#define _KERN_REGION_TABLE (_REGION_THIRD|_REGION_THIRD_LEN) + +#define USER_STD_MASK 0x0000000000000080UL + +/* Bits in the storage key */ +#define _PAGE_CHANGED 0x02 /* HW changed bit */ +#define _PAGE_REFERENCED 0x04 /* HW referenced bit */ + +#endif /* __s390x__ */ + +/* + * No mapping available + */ +#define PAGE_NONE_SHARED __pgprot(_PAGE_INVALID_NONE) +#define PAGE_NONE_PRIVATE __pgprot(_PAGE_INVALID_NONE) +#define PAGE_RO_SHARED __pgprot(_PAGE_RO) +#define PAGE_RO_PRIVATE __pgprot(_PAGE_RO) +#define PAGE_COPY __pgprot(_PAGE_RO) +#define PAGE_SHARED __pgprot(0) +#define PAGE_KERNEL __pgprot(0) + +/* + * The S390 can't do page protection for execute, and considers that the + * same are read. Also, write permissions imply read permissions. This is + * the closest we can get.. + */ + /*xwr*/ +#define __P000 PAGE_NONE_PRIVATE +#define __P001 PAGE_RO_PRIVATE +#define __P010 PAGE_COPY +#define __P011 PAGE_COPY +#define __P100 PAGE_RO_PRIVATE +#define __P101 PAGE_RO_PRIVATE +#define __P110 PAGE_COPY +#define __P111 PAGE_COPY + +#define __S000 PAGE_NONE_SHARED +#define __S001 PAGE_RO_SHARED +#define __S010 PAGE_SHARED +#define __S011 PAGE_SHARED +#define __S100 PAGE_RO_SHARED +#define __S101 PAGE_RO_SHARED +#define __S110 PAGE_SHARED +#define __S111 PAGE_SHARED + +/* + * Certain architectures need to do special things when PTEs + * within a page table are directly modified. Thus, the following + * hook is made available. + */ +extern inline void set_pte(pte_t *pteptr, pte_t pteval) +{ + *pteptr = pteval; +} +#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval) + +/* + * pgd/pmd/pte query functions + */ +#ifndef __s390x__ + +extern inline int pgd_present(pgd_t pgd) { return 1; } +extern inline int pgd_none(pgd_t pgd) { return 0; } +extern inline int pgd_bad(pgd_t pgd) { return 0; } + +extern inline int pmd_present(pmd_t pmd) { return pmd_val(pmd) & _SEG_PRESENT; } +extern inline int pmd_none(pmd_t pmd) { return pmd_val(pmd) & _PAGE_TABLE_INV; } +extern inline int pmd_bad(pmd_t pmd) +{ + return (pmd_val(pmd) & (~PAGE_MASK & ~_PAGE_TABLE_INV)) != _PAGE_TABLE; +} + +#else /* __s390x__ */ + +extern inline int pgd_present(pgd_t pgd) +{ + return (pgd_val(pgd) & ~PAGE_MASK) == _PGD_ENTRY; +} + +extern inline int pgd_none(pgd_t pgd) +{ + return pgd_val(pgd) & _PGD_ENTRY_INV; +} + +extern inline int pgd_bad(pgd_t pgd) +{ + return (pgd_val(pgd) & (~PAGE_MASK & ~_PGD_ENTRY_INV)) != _PGD_ENTRY; +} + +extern inline int pmd_present(pmd_t pmd) +{ + return (pmd_val(pmd) & ~PAGE_MASK) == _PMD_ENTRY; +} + +extern inline int pmd_none(pmd_t pmd) +{ + return pmd_val(pmd) & _PMD_ENTRY_INV; +} + +extern inline int pmd_bad(pmd_t pmd) +{ + return (pmd_val(pmd) & (~PAGE_MASK & ~_PMD_ENTRY_INV)) != _PMD_ENTRY; +} + +#endif /* __s390x__ */ + +extern inline int pte_none(pte_t pte) +{ + return (pte_val(pte) & _PAGE_INVALID_MASK) == _PAGE_INVALID_EMPTY; +} + +extern inline int pte_present(pte_t pte) +{ + return !(pte_val(pte) & _PAGE_INVALID) || + (pte_val(pte) & _PAGE_INVALID_MASK) == _PAGE_INVALID_NONE; +} + +extern inline int pte_file(pte_t pte) +{ + return (pte_val(pte) & _PAGE_INVALID_MASK) == _PAGE_INVALID_FILE; +} + +#define pte_same(a,b) (pte_val(a) == pte_val(b)) + +/* + * query functions pte_write/pte_dirty/pte_young only work if + * pte_present() is true. Undefined behaviour if not.. + */ +extern inline int pte_write(pte_t pte) +{ + return (pte_val(pte) & _PAGE_RO) == 0; +} + +extern inline int pte_dirty(pte_t pte) +{ + /* A pte is neither clean nor dirty on s/390. The dirty bit + * is in the storage key. See page_test_and_clear_dirty for + * details. + */ + return 0; +} + +extern inline int pte_young(pte_t pte) +{ + /* A pte is neither young nor old on s/390. The young bit + * is in the storage key. See page_test_and_clear_young for + * details. + */ + return 0; +} + +extern inline int pte_read(pte_t pte) +{ + /* All pages are readable since we don't use the fetch + * protection bit in the storage key. + */ + return 1; +} + +/* + * pgd/pmd/pte modification functions + */ + +#ifndef __s390x__ + +extern inline void pgd_clear(pgd_t * pgdp) { } + +extern inline void pmd_clear(pmd_t * pmdp) +{ + pmd_val(pmdp[0]) = _PAGE_TABLE_INV; + pmd_val(pmdp[1]) = _PAGE_TABLE_INV; + pmd_val(pmdp[2]) = _PAGE_TABLE_INV; + pmd_val(pmdp[3]) = _PAGE_TABLE_INV; +} + +#else /* __s390x__ */ + +extern inline void pgd_clear(pgd_t * pgdp) +{ + pgd_val(*pgdp) = _PGD_ENTRY_INV | _PGD_ENTRY; +} + +extern inline void pmd_clear(pmd_t * pmdp) +{ + pmd_val(*pmdp) = _PMD_ENTRY_INV | _PMD_ENTRY; + pmd_val1(*pmdp) = _PMD_ENTRY_INV | _PMD_ENTRY; +} + +#endif /* __s390x__ */ + +extern inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) +{ + pte_val(*ptep) = _PAGE_INVALID_EMPTY; +} + +/* + * The following pte modification functions only work if + * pte_present() is true. Undefined behaviour if not.. + */ +extern inline pte_t pte_modify(pte_t pte, pgprot_t newprot) +{ + pte_val(pte) &= PAGE_MASK; + pte_val(pte) |= pgprot_val(newprot); + return pte; +} + +extern inline pte_t pte_wrprotect(pte_t pte) +{ + /* Do not clobber _PAGE_INVALID_NONE pages! */ + if (!(pte_val(pte) & _PAGE_INVALID)) + pte_val(pte) |= _PAGE_RO; + return pte; +} + +extern inline pte_t pte_mkwrite(pte_t pte) +{ + pte_val(pte) &= ~_PAGE_RO; + return pte; +} + +extern inline pte_t pte_mkclean(pte_t pte) +{ + /* The only user of pte_mkclean is the fork() code. + We must *not* clear the *physical* page dirty bit + just because fork() wants to clear the dirty bit in + *one* of the page's mappings. So we just do nothing. */ + return pte; +} + +extern inline pte_t pte_mkdirty(pte_t pte) +{ + /* We do not explicitly set the dirty bit because the + * sske instruction is slow. It is faster to let the + * next instruction set the dirty bit. + */ + return pte; +} + +extern inline pte_t pte_mkold(pte_t pte) +{ + /* S/390 doesn't keep its dirty/referenced bit in the pte. + * There is no point in clearing the real referenced bit. + */ + return pte; +} + +extern inline pte_t pte_mkyoung(pte_t pte) +{ + /* S/390 doesn't keep its dirty/referenced bit in the pte. + * There is no point in setting the real referenced bit. + */ + return pte; +} + +static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) +{ + return 0; +} + +static inline int +ptep_clear_flush_young(struct vm_area_struct *vma, + unsigned long address, pte_t *ptep) +{ + /* No need to flush TLB; bits are in storage key */ + return ptep_test_and_clear_young(vma, address, ptep); +} + +static inline int ptep_test_and_clear_dirty(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) +{ + return 0; +} + +static inline int +ptep_clear_flush_dirty(struct vm_area_struct *vma, + unsigned long address, pte_t *ptep) +{ + /* No need to flush TLB; bits are in storage key */ + return ptep_test_and_clear_dirty(vma, address, ptep); +} + +static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) +{ + pte_t pte = *ptep; + pte_clear(mm, addr, ptep); + return pte; +} + +static inline pte_t +ptep_clear_flush(struct vm_area_struct *vma, + unsigned long address, pte_t *ptep) +{ + pte_t pte = *ptep; +#ifndef __s390x__ + if (!(pte_val(pte) & _PAGE_INVALID)) { + /* S390 has 1mb segments, we are emulating 4MB segments */ + pte_t *pto = (pte_t *) (((unsigned long) ptep) & 0x7ffffc00); + __asm__ __volatile__ ("ipte %2,%3" + : "=m" (*ptep) : "m" (*ptep), + "a" (pto), "a" (address) ); + } +#else /* __s390x__ */ + if (!(pte_val(pte) & _PAGE_INVALID)) + __asm__ __volatile__ ("ipte %2,%3" + : "=m" (*ptep) : "m" (*ptep), + "a" (ptep), "a" (address) ); +#endif /* __s390x__ */ + pte_val(*ptep) = _PAGE_INVALID_EMPTY; + return pte; +} + +static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) +{ + pte_t old_pte = *ptep; + set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte)); +} + +static inline void +ptep_establish(struct vm_area_struct *vma, + unsigned long address, pte_t *ptep, + pte_t entry) +{ + ptep_clear_flush(vma, address, ptep); + set_pte(ptep, entry); +} + +#define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \ + ptep_establish(__vma, __address, __ptep, __entry) + +/* + * 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 page_test_and_clear_dirty(_page) \ +({ \ + struct page *__page = (_page); \ + unsigned long __physpage = __pa((__page-mem_map) << PAGE_SHIFT); \ + int __skey = page_get_storage_key(__physpage); \ + if (__skey & _PAGE_CHANGED) \ + page_set_storage_key(__physpage, __skey & ~_PAGE_CHANGED);\ + (__skey & _PAGE_CHANGED); \ +}) + +/* + * Test and clear referenced bit in storage key. + */ +#define page_test_and_clear_young(page) \ +({ \ + struct page *__page = (page); \ + unsigned long __physpage = __pa((__page-mem_map) << PAGE_SHIFT); \ + int __ccode; \ + asm volatile ("rrbe 0,%1\n\t" \ + "ipm %0\n\t" \ + "srl %0,28\n\t" \ + : "=d" (__ccode) : "a" (__physpage) : "cc" ); \ + (__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; +} + +#define mk_pte(pg, pgprot) \ +({ \ + struct page *__page = (pg); \ + pgprot_t __pgprot = (pgprot); \ + unsigned long __physpage = __pa((__page-mem_map) << PAGE_SHIFT); \ + pte_t __pte = mk_pte_phys(__physpage, __pgprot); \ + __pte; \ +}) + +#define pfn_pte(pfn, pgprot) \ +({ \ + pgprot_t __pgprot = (pgprot); \ + unsigned long __physpage = __pa((pfn) << PAGE_SHIFT); \ + pte_t __pte = mk_pte_phys(__physpage, __pgprot); \ + __pte; \ +}) + +#define SetPageUptodate(_page) \ + do { \ + struct page *__page = (_page); \ + if (!test_and_set_bit(PG_uptodate, &__page->flags)) \ + page_test_and_clear_dirty(_page); \ + } while (0) + +#ifdef __s390x__ + +#define pfn_pmd(pfn, pgprot) \ +({ \ + pgprot_t __pgprot = (pgprot); \ + unsigned long __physpage = __pa((pfn) << PAGE_SHIFT); \ + pmd_t __pmd = __pmd(__physpage + pgprot_val(__pgprot)); \ + __pmd; \ +}) + +#endif /* __s390x__ */ + +#define pte_pfn(x) (pte_val(x) >> PAGE_SHIFT) +#define pte_page(x) pfn_to_page(pte_pfn(x)) + +#define pmd_page_kernel(pmd) (pmd_val(pmd) & PAGE_MASK) + +#define pmd_page(pmd) (mem_map+(pmd_val(pmd) >> PAGE_SHIFT)) + +#define pgd_page_kernel(pgd) (pgd_val(pgd) & PAGE_MASK) + +/* to find an entry in a page-table-directory */ +#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1)) +#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address)) + +/* to find an entry in a kernel page-table-directory */ +#define pgd_offset_k(address) pgd_offset(&init_mm, address) + +#ifndef __s390x__ + +/* Find an entry in the second-level page table.. */ +extern inline pmd_t * pmd_offset(pgd_t * dir, unsigned long address) +{ + return (pmd_t *) dir; +} + +#else /* __s390x__ */ + +/* Find an entry in the second-level page table.. */ +#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1)) +#define pmd_offset(dir,addr) \ + ((pmd_t *) pgd_page_kernel(*(dir)) + pmd_index(addr)) + +#endif /* __s390x__ */ + +/* Find an entry in the third-level page table.. */ +#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1)) +#define pte_offset_kernel(pmd, address) \ + ((pte_t *) pmd_page_kernel(*(pmd)) + pte_index(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 +extern inline pte_t mk_swap_pte(unsigned long type, unsigned long offset) +{ + pte_t pte; + offset &= __SWP_OFFSET_MASK; + pte_val(pte) = _PAGE_INVALID_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_INVALID_FILE }) + +#endif /* !__ASSEMBLY__ */ + +#define kern_addr_valid(addr) (1) + +/* + * No page table caches to initialise + */ +#define pgtable_cache_init() do { } while (0) + +#define __HAVE_ARCH_PTEP_ESTABLISH +#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS +#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG +#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH +#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY +#define __HAVE_ARCH_PTEP_CLEAR_DIRTY_FLUSH +#define __HAVE_ARCH_PTEP_GET_AND_CLEAR +#define __HAVE_ARCH_PTEP_CLEAR_FLUSH +#define __HAVE_ARCH_PTEP_SET_WRPROTECT +#define __HAVE_ARCH_PTE_SAME +#define __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY +#define __HAVE_ARCH_PAGE_TEST_AND_CLEAR_YOUNG +#include <asm-generic/pgtable.h> + +#endif /* _S390_PAGE_H */ + |