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Commit 152125b7 authored by Martin Schwidefsky's avatar Martin Schwidefsky
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s390/mm: implement dirty bits for large segment table entries 

The large segment table entry format has block of bits for the
ACC/F values for the large page. These bits are valid only if
another bit (AV bit 0x10000) of the segment table entry is set.
The ACC/F bits do not have a meaning if the AV bit is off.
This allows to put the THP splitting bit, the segment young bit
and the new segment dirty bit into the ACC/F bits as long as
the AV bit stays off. The dirty and young information is only
available if the pmd is large.
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 55e4283c
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Showing with 159 additions and 144 deletions
arch/s390/include/asm/pgtable.h
View file @ 152125b7
......@@ -287,7 +287,14 @@ extern unsigned long MODULES_END;
#define _SEGMENT_ENTRY_INVALID 0x20 /* invalid segment table entry */
#define _SEGMENT_ENTRY_COMMON 0x10 /* common segment bit */
#define _SEGMENT_ENTRY_PTL 0x0f /* page table length */
#define _SEGMENT_ENTRY_NONE _SEGMENT_ENTRY_PROTECT
#define _SEGMENT_ENTRY_DIRTY 0 /* No sw dirty bit for 31-bit */
#define _SEGMENT_ENTRY_YOUNG 0 /* No sw young bit for 31-bit */
#define _SEGMENT_ENTRY_READ 0 /* No sw read bit for 31-bit */
#define _SEGMENT_ENTRY_WRITE 0 /* No sw write bit for 31-bit */
#define _SEGMENT_ENTRY_LARGE 0 /* No large pages for 31-bit */
#define _SEGMENT_ENTRY_BITS_LARGE 0
#define _SEGMENT_ENTRY_ORIGIN_LARGE 0
#define _SEGMENT_ENTRY (_SEGMENT_ENTRY_PTL)
#define _SEGMENT_ENTRY_EMPTY (_SEGMENT_ENTRY_INVALID)
......@@ -350,7 +357,7 @@ extern unsigned long MODULES_END;
/* Bits in the segment table entry */
#define _SEGMENT_ENTRY_BITS 0xfffffffffffffe33UL
#define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff1ff33UL
#define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff0ff33UL
#define _SEGMENT_ENTRY_ORIGIN_LARGE ~0xfffffUL /* large page address */
#define _SEGMENT_ENTRY_ORIGIN ~0x7ffUL/* segment table origin */
#define _SEGMENT_ENTRY_PROTECT 0x200 /* page protection bit */
......@@ -359,30 +366,34 @@ extern unsigned long MODULES_END;
#define _SEGMENT_ENTRY (0)
#define _SEGMENT_ENTRY_EMPTY (_SEGMENT_ENTRY_INVALID)
#define _SEGMENT_ENTRY_LARGE 0x400 /* STE-format control, large page */
#define _SEGMENT_ENTRY_CO 0x100 /* change-recording override */
#define _SEGMENT_ENTRY_SPLIT 0x001 /* THP splitting bit */
#define _SEGMENT_ENTRY_YOUNG 0x002 /* SW segment young bit */
#define _SEGMENT_ENTRY_NONE _SEGMENT_ENTRY_YOUNG
#define _SEGMENT_ENTRY_DIRTY 0x2000 /* SW segment dirty bit */
#define _SEGMENT_ENTRY_YOUNG 0x1000 /* SW segment young bit */
#define _SEGMENT_ENTRY_SPLIT 0x0800 /* THP splitting bit */
#define _SEGMENT_ENTRY_LARGE 0x0400 /* STE-format control, large page */
#define _SEGMENT_ENTRY_CO 0x0100 /* change-recording override */
#define _SEGMENT_ENTRY_READ 0x0002 /* SW segment read bit */
#define _SEGMENT_ENTRY_WRITE 0x0001 /* SW segment write bit */
/*
* Segment table entry encoding (R = read-only, I = invalid, y = young bit):
* ..R...I...y.
* prot-none, old ..0...1...1.
* prot-none, young ..1...1...1.
* read-only, old ..1...1...0.
* read-only, young ..1...0...1.
* read-write, old ..0...1...0.
* read-write, young ..0...0...1.
* dy..R...I...wr
* prot-none, clean, old 00..1...1...00
* prot-none, clean, young 01..1...1...00
* prot-none, dirty, old 10..1...1...00
* prot-none, dirty, young 11..1...1...00
* read-only, clean, old 00..1...1...01
* read-only, clean, young 01..1...0...01
* read-only, dirty, old 10..1...1...01
* read-only, dirty, young 11..1...0...01
* read-write, clean, old 00..1...1...11
* read-write, clean, young 01..1...0...11
* read-write, dirty, old 10..0...1...11
* read-write, dirty, young 11..0...0...11
* The segment table origin is used to distinguish empty (origin==0) from
* read-write, old segment table entries (origin!=0)
*/
#define _SEGMENT_ENTRY_SPLIT_BIT 0 /* THP splitting bit number */
/* Set of bits not changed in pmd_modify */
#define _SEGMENT_CHG_MASK (_SEGMENT_ENTRY_ORIGIN | _SEGMENT_ENTRY_LARGE \
| _SEGMENT_ENTRY_SPLIT | _SEGMENT_ENTRY_CO)
#define _SEGMENT_ENTRY_SPLIT_BIT 11 /* THP splitting bit number */
/* Page status table bits for virtualization */
#define PGSTE_ACC_BITS 0xf000000000000000UL
......@@ -455,10 +466,11 @@ extern unsigned long MODULES_END;
* Segment entry (large page) protection definitions.
*/
#define SEGMENT_NONE __pgprot(_SEGMENT_ENTRY_INVALID | \
_SEGMENT_ENTRY_NONE)
#define SEGMENT_READ __pgprot(_SEGMENT_ENTRY_INVALID | \
_SEGMENT_ENTRY_PROTECT)
#define SEGMENT_WRITE __pgprot(_SEGMENT_ENTRY_INVALID)
#define SEGMENT_READ __pgprot(_SEGMENT_ENTRY_PROTECT | \
_SEGMENT_ENTRY_READ)
#define SEGMENT_WRITE __pgprot(_SEGMENT_ENTRY_READ | \
_SEGMENT_ENTRY_WRITE)
static inline int mm_has_pgste(struct mm_struct *mm)
{
......@@ -569,25 +581,23 @@ static inline int pmd_none(pmd_t pmd)
static inline int pmd_large(pmd_t pmd)
{
#ifdef CONFIG_64BIT
return (pmd_val(pmd) & _SEGMENT_ENTRY_LARGE) != 0;
#else
return 0;
#endif
}
static inline int pmd_prot_none(pmd_t pmd)
static inline int pmd_pfn(pmd_t pmd)
{
return (pmd_val(pmd) & _SEGMENT_ENTRY_INVALID) &&
(pmd_val(pmd) & _SEGMENT_ENTRY_NONE);
unsigned long origin_mask;
origin_mask = _SEGMENT_ENTRY_ORIGIN;
if (pmd_large(pmd))
origin_mask = _SEGMENT_ENTRY_ORIGIN_LARGE;
return (pmd_val(pmd) & origin_mask) >> PAGE_SHIFT;
}
static inline int pmd_bad(pmd_t pmd)
{
#ifdef CONFIG_64BIT
if (pmd_large(pmd))
return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS_LARGE) != 0;
#endif
return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS) != 0;
}
......@@ -607,20 +617,22 @@ extern int pmdp_clear_flush_young(struct vm_area_struct *vma,
#define __HAVE_ARCH_PMD_WRITE
static inline int pmd_write(pmd_t pmd)
{
if (pmd_prot_none(pmd))
return 0;
return (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT) == 0;
return (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE) != 0;
}
static inline int pmd_dirty(pmd_t pmd)
{
int dirty = 1;
if (pmd_large(pmd))
dirty = (pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY) != 0;
return dirty;
}
static inline int pmd_young(pmd_t pmd)
{
int young = 0;
#ifdef CONFIG_64BIT
if (pmd_prot_none(pmd))
young = (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT) != 0;
else
int young = 1;
if (pmd_large(pmd))
young = (pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG) != 0;
#endif
return young;
}
......@@ -1391,7 +1403,7 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
#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)
#define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))
/* Find an entry in the lowest level page table.. */
#define pte_offset(pmd, addr) ((pte_t *) pmd_deref(*(pmd)) + pte_index(addr))
......@@ -1413,41 +1425,75 @@ static inline unsigned long massage_pgprot_pmd(pgprot_t pgprot)
return pgprot_val(SEGMENT_WRITE);
}
static inline pmd_t pmd_mkyoung(pmd_t pmd)
static inline pmd_t pmd_wrprotect(pmd_t pmd)
{
#ifdef CONFIG_64BIT
if (pmd_prot_none(pmd)) {
pmd_val(pmd) &= ~_SEGMENT_ENTRY_WRITE;
pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
return pmd;
}
static inline pmd_t pmd_mkwrite(pmd_t pmd)
{
pmd_val(pmd) |= _SEGMENT_ENTRY_WRITE;
if (pmd_large(pmd) && !(pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY))
return pmd;
pmd_val(pmd) &= ~_SEGMENT_ENTRY_PROTECT;
return pmd;
}
static inline pmd_t pmd_mkclean(pmd_t pmd)
{
if (pmd_large(pmd)) {
pmd_val(pmd) &= ~_SEGMENT_ENTRY_DIRTY;
pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
} else {
}
return pmd;
}
static inline pmd_t pmd_mkdirty(pmd_t pmd)
{
if (pmd_large(pmd)) {
pmd_val(pmd) |= _SEGMENT_ENTRY_DIRTY;
if (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE)
pmd_val(pmd) &= ~_SEGMENT_ENTRY_PROTECT;
}
return pmd;
}
static inline pmd_t pmd_mkyoung(pmd_t pmd)
{
if (pmd_large(pmd)) {
pmd_val(pmd) |= _SEGMENT_ENTRY_YOUNG;
pmd_val(pmd) &= ~_SEGMENT_ENTRY_INVALID;
if (pmd_val(pmd) & _SEGMENT_ENTRY_READ)
pmd_val(pmd) &= ~_SEGMENT_ENTRY_INVALID;
}
#endif
return pmd;
}
static inline pmd_t pmd_mkold(pmd_t pmd)
{
#ifdef CONFIG_64BIT
if (pmd_prot_none(pmd)) {
pmd_val(pmd) &= ~_SEGMENT_ENTRY_PROTECT;
} else {
if (pmd_large(pmd)) {
pmd_val(pmd) &= ~_SEGMENT_ENTRY_YOUNG;
pmd_val(pmd) |= _SEGMENT_ENTRY_INVALID;
}
#endif
return pmd;
}
static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
{
int young;
young = pmd_young(pmd);
pmd_val(pmd) &= _SEGMENT_CHG_MASK;
if (pmd_large(pmd)) {
pmd_val(pmd) &= _SEGMENT_ENTRY_ORIGIN_LARGE |
_SEGMENT_ENTRY_DIRTY | _SEGMENT_ENTRY_YOUNG |
_SEGMENT_ENTRY_LARGE | _SEGMENT_ENTRY_SPLIT;
pmd_val(pmd) |= massage_pgprot_pmd(newprot);
if (!(pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY))
pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
if (!(pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG))
pmd_val(pmd) |= _SEGMENT_ENTRY_INVALID;
return pmd;
}
pmd_val(pmd) &= _SEGMENT_ENTRY_ORIGIN;
pmd_val(pmd) |= massage_pgprot_pmd(newprot);
if (young)
pmd = pmd_mkyoung(pmd);
return pmd;
}
......@@ -1455,16 +1501,9 @@ static inline pmd_t mk_pmd_phys(unsigned long physpage, pgprot_t pgprot)
{
pmd_t __pmd;
pmd_val(__pmd) = physpage + massage_pgprot_pmd(pgprot);
return pmd_mkyoung(__pmd);
return __pmd;
}
static inline pmd_t pmd_mkwrite(pmd_t pmd)
{
/* Do not clobber PROT_NONE segments! */
if (!pmd_prot_none(pmd))
pmd_val(pmd) &= ~_SEGMENT_ENTRY_PROTECT;
return pmd;
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLB_PAGE */
static inline void __pmdp_csp(pmd_t *pmdp)
......@@ -1555,34 +1594,21 @@ extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
static inline int pmd_trans_splitting(pmd_t pmd)
{
return pmd_val(pmd) & _SEGMENT_ENTRY_SPLIT;
return (pmd_val(pmd) & _SEGMENT_ENTRY_LARGE) &&
(pmd_val(pmd) & _SEGMENT_ENTRY_SPLIT);
}
static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t entry)
{
if (!(pmd_val(entry) & _SEGMENT_ENTRY_INVALID) && MACHINE_HAS_EDAT1)
pmd_val(entry) |= _SEGMENT_ENTRY_CO;
*pmdp = entry;
}
static inline pmd_t pmd_mkhuge(pmd_t pmd)
{
pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
return pmd;
}
static inline pmd_t pmd_wrprotect(pmd_t pmd)
{
/* Do not clobber PROT_NONE segments! */
if (!pmd_prot_none(pmd))
pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
return pmd;
}
static inline pmd_t pmd_mkdirty(pmd_t pmd)
{
/* No dirty bit in the segment table entry. */
pmd_val(pmd) |= _SEGMENT_ENTRY_YOUNG;
pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
return pmd;
}
......@@ -1647,11 +1673,6 @@ static inline int has_transparent_hugepage(void)
{
return MACHINE_HAS_HPAGE ? 1 : 0;
}
static inline unsigned long pmd_pfn(pmd_t pmd)
{
return pmd_val(pmd) >> PAGE_SHIFT;
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
/*
......
arch/s390/mm/hugetlbpage.c
View file @ 152125b7
......@@ -10,42 +10,33 @@
static inline pmd_t __pte_to_pmd(pte_t pte)
{
int none, young, prot;
pmd_t pmd;
/*
* Convert encoding pte bits pmd bits
* .IR...wrdytp ..R...I...y.
* empty .10...000000 -> ..0...1...0.
* prot-none, clean, old .11...000001 -> ..0...1...1.
* prot-none, clean, young .11...000101 -> ..1...1...1.
* prot-none, dirty, old .10...001001 -> ..0...1...1.
* prot-none, dirty, young .10...001101 -> ..1...1...1.
* read-only, clean, old .11...010001 -> ..1...1...0.
* read-only, clean, young .01...010101 -> ..1...0...1.
* read-only, dirty, old .11...011001 -> ..1...1...0.
* read-only, dirty, young .01...011101 -> ..1...0...1.
* read-write, clean, old .11...110001 -> ..0...1...0.
* read-write, clean, young .01...110101 -> ..0...0...1.
* read-write, dirty, old .10...111001 -> ..0...1...0.
* read-write, dirty, young .00...111101 -> ..0...0...1.
* Huge ptes are dirty by definition, a clean pte is made dirty
* by the conversion.
* Convert encoding pte bits pmd bits
* .IR...wrdytp dy..R...I...wr
* empty .10...000000 -> 00..0...1...00
* prot-none, clean, old .11...000001 -> 00..1...1...00
* prot-none, clean, young .11...000101 -> 01..1...1...00
* prot-none, dirty, old .10...001001 -> 10..1...1...00
* prot-none, dirty, young .10...001101 -> 11..1...1...00
* read-only, clean, old .11...010001 -> 00..1...1...01
* read-only, clean, young .01...010101 -> 01..1...0...01
* read-only, dirty, old .11...011001 -> 10..1...1...01
* read-only, dirty, young .01...011101 -> 11..1...0...01
* read-write, clean, old .11...110001 -> 00..0...1...11
* read-write, clean, young .01...110101 -> 01..0...0...11
* read-write, dirty, old .10...111001 -> 10..0...1...11
* read-write, dirty, young .00...111101 -> 11..0...0...11
*/
if (pte_present(pte)) {
pmd_val(pmd) = pte_val(pte) & PAGE_MASK;
if (pte_val(pte) & _PAGE_INVALID)
pmd_val(pmd) |= _SEGMENT_ENTRY_INVALID;
none = (pte_val(pte) & _PAGE_PRESENT) &&
!(pte_val(pte) & _PAGE_READ) &&
!(pte_val(pte) & _PAGE_WRITE);
prot = (pte_val(pte) & _PAGE_PROTECT) &&
!(pte_val(pte) & _PAGE_WRITE);
young = pte_val(pte) & _PAGE_YOUNG;
if (none || young)
pmd_val(pmd) |= _SEGMENT_ENTRY_YOUNG;
if (prot || (none && young))
pmd_val(pmd) |= _SEGMENT_ENTRY_PROTECT;
pmd_val(pmd) |= (pte_val(pte) & _PAGE_READ) >> 4;
pmd_val(pmd) |= (pte_val(pte) & _PAGE_WRITE) >> 4;
pmd_val(pmd) |= (pte_val(pte) & _PAGE_INVALID) >> 5;
pmd_val(pmd) |= (pte_val(pte) & _PAGE_PROTECT);
pmd_val(pmd) |= (pte_val(pte) & _PAGE_DIRTY) << 10;
pmd_val(pmd) |= (pte_val(pte) & _PAGE_YOUNG) << 10;
} else
pmd_val(pmd) = _SEGMENT_ENTRY_INVALID;
return pmd;
......@@ -56,34 +47,31 @@ static inline pte_t __pmd_to_pte(pmd_t pmd)
pte_t pte;
/*
* Convert encoding pmd bits pte bits
* ..R...I...y. .IR...wrdytp
* empty ..0...1...0. -> .10...000000
* prot-none, old ..0...1...1. -> .10...001001
* prot-none, young ..1...1...1. -> .10...001101
* read-only, old ..1...1...0. -> .11...011001
* read-only, young ..1...0...1. -> .01...011101
* read-write, old ..0...1...0. -> .10...111001
* read-write, young ..0...0...1. -> .00...111101
* Huge ptes are dirty by definition
* Convert encoding pmd bits pte bits
* dy..R...I...wr .IR...wrdytp
* empty 00..0...1...00 -> .10...001100
* prot-none, clean, old 00..0...1...00 -> .10...000001
* prot-none, clean, young 01..0...1...00 -> .10...000101
* prot-none, dirty, old 10..0...1...00 -> .10...001001
* prot-none, dirty, young 11..0...1...00 -> .10...001101
* read-only, clean, old 00..1...1...01 -> .11...010001
* read-only, clean, young 01..1...1...01 -> .11...010101
* read-only, dirty, old 10..1...1...01 -> .11...011001
* read-only, dirty, young 11..1...1...01 -> .11...011101
* read-write, clean, old 00..0...1...11 -> .10...110001
* read-write, clean, young 01..0...1...11 -> .10...110101
* read-write, dirty, old 10..0...1...11 -> .10...111001
* read-write, dirty, young 11..0...1...11 -> .10...111101
*/
if (pmd_present(pmd)) {
pte_val(pte) = _PAGE_PRESENT | _PAGE_LARGE | _PAGE_DIRTY |
(pmd_val(pmd) & PAGE_MASK);
if (pmd_val(pmd) & _SEGMENT_ENTRY_INVALID)
pte_val(pte) |= _PAGE_INVALID;
if (pmd_prot_none(pmd)) {
if (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT)
pte_val(pte) |= _PAGE_YOUNG;
} else {
pte_val(pte) |= _PAGE_READ;
if (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT)
pte_val(pte) |= _PAGE_PROTECT;
else
pte_val(pte) |= _PAGE_WRITE;
if (pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG)
pte_val(pte) |= _PAGE_YOUNG;
}
pte_val(pte) = pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN_LARGE;
pte_val(pte) |= _PAGE_LARGE | _PAGE_PRESENT;
pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_READ) << 4;
pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE) << 4;
pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_INVALID) << 5;
pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT);
pmd_val(pmd) |= (pte_val(pte) & _PAGE_DIRTY) << 10;
pmd_val(pmd) |= (pte_val(pte) & _PAGE_YOUNG) << 10;
} else
pte_val(pte) = _PAGE_INVALID;
return pte;
......@@ -96,6 +84,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
pmd = __pte_to_pmd(pte);
if (!MACHINE_HAS_HPAGE) {
/* Emulated huge ptes loose the dirty and young bit */
pmd_val(pmd) &= ~_SEGMENT_ENTRY_ORIGIN;
pmd_val(pmd) |= pte_page(pte)[1].index;
} else
......@@ -113,6 +102,8 @@ pte_t huge_ptep_get(pte_t *ptep)
origin = pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN;
pmd_val(pmd) &= ~_SEGMENT_ENTRY_ORIGIN;
pmd_val(pmd) |= *(unsigned long *) origin;
/* Emulated huge ptes are young and dirty by definition */
pmd_val(pmd) |= _SEGMENT_ENTRY_YOUNG | _SEGMENT_ENTRY_DIRTY;
}
return __pmd_to_pte(pmd);
}
......
arch/s390/mm/pgtable.c
View file @ 152125b7
......@@ -1433,6 +1433,9 @@ int pmdp_set_access_flags(struct vm_area_struct *vma,
{
VM_BUG_ON(address & ~HPAGE_PMD_MASK);
entry = pmd_mkyoung(entry);
if (dirty)
entry = pmd_mkdirty(entry);
if (pmd_same(*pmdp, entry))
return 0;
pmdp_invalidate(vma, address, pmdp);
......
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