This implements the architecture backend for transparent hugepages on System z.
Signed-off-by: Gerald Schaefer <[email protected]> --- arch/s390/include/asm/hugetlb.h | 18 ---- arch/s390/include/asm/pgtable.h | 176 ++++++++++++++++++++++++++++++++++++++++ arch/s390/include/asm/tlb.h | 1 arch/s390/mm/pgtable.c | 22 +++++ mm/Kconfig | 2 5 files changed, 201 insertions(+), 18 deletions(-) --- a/arch/s390/include/asm/hugetlb.h +++ b/arch/s390/include/asm/hugetlb.h @@ -87,23 +87,6 @@ static inline void __pmd_csp(pmd_t *pmdp " csp %1,%3" : "=m" (*pmdp) : "d" (reg2), "d" (reg3), "d" (reg4), "m" (*pmdp) : "cc"); - pmd_val(*pmdp) = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY; -} - -static inline void __pmd_idte(unsigned long address, pmd_t *pmdp) -{ - unsigned long sto = (unsigned long) pmdp - - pmd_index(address) * sizeof(pmd_t); - - if (!(pmd_val(*pmdp) & _SEGMENT_ENTRY_INV)) { - asm volatile( - " .insn rrf,0xb98e0000,%2,%3,0,0" - : "=m" (*pmdp) - : "m" (*pmdp), "a" (sto), - "a" ((address & HPAGE_MASK)) - ); - } - pmd_val(*pmdp) = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY; } static inline void huge_ptep_invalidate(struct mm_struct *mm, @@ -115,6 +98,7 @@ static inline void huge_ptep_invalidate( __pmd_idte(address, pmdp); else __pmd_csp(pmdp); + pmd_val(*pmdp) = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY; } #define huge_ptep_set_access_flags(__vma, __addr, __ptep, __entry, __dirty) \ --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -350,6 +350,10 @@ extern struct page *vmemmap; #define _SEGMENT_ENTRY_SPLIT_BIT 0 /* THP splitting bit number */ #define _SEGMENT_ENTRY_SPLIT (1UL << _SEGMENT_ENTRY_SPLIT_BIT) +/* Set of bits not changed in pmd_modify */ +#define _SEGMENT_CHG_MASK (_SEGMENT_ENTRY_ORIGIN | _SEGMENT_ENTRY_LARGE \ + | _SEGMENT_ENTRY_SPLIT | _SEGMENT_ENTRY_CO) + /* Page status table bits for virtualization */ #define RCP_ACC_BITS 0xf000000000000000UL #define RCP_FP_BIT 0x0800000000000000UL @@ -512,6 +516,26 @@ static inline int pmd_bad(pmd_t pmd) extern void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long addr, pmd_t *pmdp); +#define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS +extern int pmdp_set_access_flags(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp, + pmd_t entry, int dirty); + +#define __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH +extern int pmdp_clear_flush_young(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp); + +#define __HAVE_ARCH_PMD_WRITE +static inline int pmd_write(pmd_t pmd) +{ + return (pmd_val(pmd) & _SEGMENT_ENTRY_RO) == 0; +} + +static inline int pmd_young(pmd_t pmd) +{ + return 0; +} + static inline int pte_none(pte_t pte) { return (pte_val(pte) & _PAGE_INVALID) && !(pte_val(pte) & _PAGE_SWT); @@ -1165,6 +1189,22 @@ static inline pmd_t *pmd_offset(pud_t *p #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address) #define pte_unmap(pte) do { } while (0) +static inline void __pmd_idte(unsigned long address, pmd_t *pmdp) +{ + unsigned long sto = (unsigned long) pmdp - + pmd_index(address) * sizeof(pmd_t); + + if (!(pmd_val(*pmdp) & _SEGMENT_ENTRY_INV)) { + asm volatile( + " .insn rrf,0xb98e0000,%2,%3,0,0" + : "=m" (*pmdp) + : "m" (*pmdp), "a" (sto), + "a" ((address & HPAGE_MASK)) + : "cc" + ); + } +} + #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define __HAVE_ARCH_PGTABLE_DEPOSIT extern void pgtable_deposit(struct mm_struct *mm, pgtable_t pgtable); @@ -1176,6 +1216,142 @@ static inline int pmd_trans_splitting(pm { return 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) +{ + *pmdp = entry; +} + +static inline unsigned long massage_pgprot_pmd(pgprot_t pgprot) +{ + unsigned long pgprot_pmd = 0; + + if (pgprot_val(pgprot) & _PAGE_INVALID) { + if (pgprot_val(pgprot) & _PAGE_SWT) + pgprot_pmd |= _HPAGE_TYPE_NONE; + pgprot_pmd |= _SEGMENT_ENTRY_INV; + } + if (pgprot_val(pgprot) & _PAGE_RO) + pgprot_pmd |= _SEGMENT_ENTRY_RO; + return pgprot_pmd; +} + +static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) +{ + pmd_val(pmd) &= _SEGMENT_CHG_MASK; + pmd_val(pmd) |= massage_pgprot_pmd(newprot); + return pmd; +} + +static inline pmd_t pmd_mkhuge(pmd_t pmd) +{ + pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE; + return pmd; +} + +static inline pmd_t pmd_mkwrite(pmd_t pmd) +{ + pmd_val(pmd) &= ~_SEGMENT_ENTRY_RO; + return pmd; +} + +static inline pmd_t pmd_wrprotect(pmd_t pmd) +{ + pmd_val(pmd) |= _SEGMENT_ENTRY_RO; + return pmd; +} + +static inline pmd_t pmd_mkdirty(pmd_t pmd) +{ + /* No dirty bit in the segment table entry. */ + return pmd; +} + +static inline pmd_t pmd_mkold(pmd_t pmd) +{ + /* No referenced bit in the segment table entry. */ + return pmd; +} + +static inline pmd_t pmd_mkyoung(pmd_t pmd) +{ + /* No referenced bit in the segment table entry. */ + return pmd; +} + +#define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG +static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, + unsigned long address, + pmd_t *pmdp) +{ + int rc = 0; + int counter = PTRS_PER_PTE; + unsigned long pmd_addr = pmd_val(*pmdp) & HPAGE_MASK; + + asm volatile( + "0: rrbe 0,%2\n" + " la %2,0(%3,%2)\n" + " brc 12,1f\n" + " lhi %0,1\n" + "1: brct %1,0b\n" + : "+d" (rc), "+d" (counter), "+a" (pmd_addr) + : "a" (4096UL): "cc" ); + return rc; +} + +#define __HAVE_ARCH_PMDP_GET_AND_CLEAR +static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm, + unsigned long address, pmd_t *pmdp) +{ + pmd_t pmd = *pmdp; + + __pmd_idte(address, pmdp); + pmd_clear(pmdp); + return pmd; +} + +#define __HAVE_ARCH_PMDP_CLEAR_FLUSH +static inline pmd_t pmdp_clear_flush(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp) +{ + return pmdp_get_and_clear(vma->vm_mm, address, pmdp); +} + +#define __HAVE_ARCH_PMDP_INVALIDATE +static inline void pmdp_invalidate(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp) +{ + __pmd_idte(address, pmdp); +} + +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; +} + +#define pfn_pmd(pfn, pgprot) mk_pmd_phys(__pa((pfn) << PAGE_SHIFT),(pgprot)) +#define mk_pmd(page, pgprot) pfn_pmd(page_to_pfn(page), (pgprot)) + +static inline int pmd_trans_huge(pmd_t pmd) +{ + return pmd_val(pmd) & _SEGMENT_ENTRY_LARGE; +} + +static inline int has_transparent_hugepage(void) +{ + return MACHINE_HAS_HPAGE ? 1 : 0; +} + +static inline unsigned long pmd_pfn(pmd_t pmd) +{ + if (pmd_trans_huge(pmd)) + return pmd_val(pmd) >> HPAGE_SHIFT; + else + return pmd_val(pmd) >> PAGE_SHIFT; +} #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ /* --- a/arch/s390/include/asm/tlb.h +++ b/arch/s390/include/asm/tlb.h @@ -137,6 +137,7 @@ static inline void pud_free_tlb(struct m #define tlb_start_vma(tlb, vma) do { } while (0) #define tlb_end_vma(tlb, vma) do { } while (0) #define tlb_remove_tlb_entry(tlb, ptep, addr) do { } while (0) +#define tlb_remove_pmd_tlb_entry(tlb, pmdp, addr) do { } while (0) #define tlb_migrate_finish(mm) do { } while (0) #endif /* _S390_TLB_H */ --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -898,6 +898,28 @@ bool kernel_page_present(struct page *pa #endif /* CONFIG_HIBERNATION && CONFIG_DEBUG_PAGEALLOC */ #ifdef CONFIG_TRANSPARENT_HUGEPAGE +int pmdp_clear_flush_young(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp) +{ + VM_BUG_ON(address & ~HPAGE_PMD_MASK); + /* No need to flush TLB + * On s390 reference bits are in storage key and never in TLB */ + return pmdp_test_and_clear_young(vma, address, pmdp); +} + +int pmdp_set_access_flags(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp, + pmd_t entry, int dirty) +{ + VM_BUG_ON(address & ~HPAGE_PMD_MASK); + + if (pmd_same(*pmdp, entry)) + return 0; + pmdp_invalidate(vma, address, pmdp); + set_pmd_at(vma->vm_mm, address, pmdp, entry); + return 1; +} + static void pmdp_splitting_flush_sync(void *arg) { /* Simply deliver the interrupt */ --- a/mm/Kconfig +++ b/mm/Kconfig @@ -318,7 +318,7 @@ config NOMMU_INITIAL_TRIM_EXCESS config TRANSPARENT_HUGEPAGE bool "Transparent Hugepage Support" - depends on X86 && MMU + depends on (X86 || (S390 && 64BIT)) && MMU select COMPACTION help Transparent Hugepages allows the kernel to use huge pages and -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
