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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-s390/pgtable.h
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-s390/pgtable.h')
-rw-r--r--include/asm-s390/pgtable.h813
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
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--- /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 */
+