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Diffstat (limited to 'include/asm-s390/tlb.h')
| -rw-r--r-- | include/asm-s390/tlb.h | 156 |
1 files changed, 0 insertions, 156 deletions
diff --git a/include/asm-s390/tlb.h b/include/asm-s390/tlb.h deleted file mode 100644 index 3d8a96d..0000000 --- a/include/asm-s390/tlb.h +++ /dev/null @@ -1,156 +0,0 @@ -#ifndef _S390_TLB_H -#define _S390_TLB_H - -/* - * TLB flushing on s390 is complicated. The following requirement - * from the principles of operation is the most arduous: - * - * "A valid table entry must not be changed while it is attached - * to any CPU and may be used for translation by that CPU except to - * (1) invalidate the entry by using INVALIDATE PAGE TABLE ENTRY, - * or INVALIDATE DAT TABLE ENTRY, (2) alter bits 56-63 of a page - * table entry, or (3) make a change by means of a COMPARE AND SWAP - * AND PURGE instruction that purges the TLB." - * - * The modification of a pte of an active mm struct therefore is - * a two step process: i) invalidate the pte, ii) store the new pte. - * This is true for the page protection bit as well. - * The only possible optimization is to flush at the beginning of - * a tlb_gather_mmu cycle if the mm_struct is currently not in use. - * - * Pages used for the page tables is a different story. FIXME: more - */ - -#include <linux/mm.h> -#include <linux/swap.h> -#include <asm/processor.h> -#include <asm/pgalloc.h> -#include <asm/smp.h> -#include <asm/tlbflush.h> - -#ifndef CONFIG_SMP -#define TLB_NR_PTRS 1 -#else -#define TLB_NR_PTRS 508 -#endif - -struct mmu_gather { - struct mm_struct *mm; - unsigned int fullmm; - unsigned int nr_ptes; - unsigned int nr_pxds; - void *array[TLB_NR_PTRS]; -}; - -DECLARE_PER_CPU(struct mmu_gather, mmu_gathers); - -static inline struct mmu_gather *tlb_gather_mmu(struct mm_struct *mm, - unsigned int full_mm_flush) -{ - struct mmu_gather *tlb = &get_cpu_var(mmu_gathers); - - tlb->mm = mm; - tlb->fullmm = full_mm_flush || (num_online_cpus() == 1) || - (atomic_read(&mm->mm_users) <= 1 && mm == current->active_mm); - tlb->nr_ptes = 0; - tlb->nr_pxds = TLB_NR_PTRS; - if (tlb->fullmm) - __tlb_flush_mm(mm); - return tlb; -} - -static inline void tlb_flush_mmu(struct mmu_gather *tlb, - unsigned long start, unsigned long end) -{ - if (!tlb->fullmm && (tlb->nr_ptes > 0 || tlb->nr_pxds < TLB_NR_PTRS)) - __tlb_flush_mm(tlb->mm); - while (tlb->nr_ptes > 0) - pte_free(tlb->mm, tlb->array[--tlb->nr_ptes]); - while (tlb->nr_pxds < TLB_NR_PTRS) - /* pgd_free frees the pointer as region or segment table */ - pgd_free(tlb->mm, tlb->array[tlb->nr_pxds++]); -} - -static inline void tlb_finish_mmu(struct mmu_gather *tlb, - unsigned long start, unsigned long end) -{ - tlb_flush_mmu(tlb, start, end); - - /* keep the page table cache within bounds */ - check_pgt_cache(); - - put_cpu_var(mmu_gathers); -} - -/* - * Release the page cache reference for a pte removed by - * tlb_ptep_clear_flush. In both flush modes the tlb fo a page cache page - * has already been freed, so just do free_page_and_swap_cache. - */ -static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page) -{ - free_page_and_swap_cache(page); -} - -/* - * pte_free_tlb frees a pte table and clears the CRSTE for the - * page table from the tlb. - */ -static inline void pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte) -{ - if (!tlb->fullmm) { - tlb->array[tlb->nr_ptes++] = pte; - if (tlb->nr_ptes >= tlb->nr_pxds) - tlb_flush_mmu(tlb, 0, 0); - } else - pte_free(tlb->mm, pte); -} - -/* - * pmd_free_tlb frees a pmd table and clears the CRSTE for the - * segment table entry from the tlb. - * If the mm uses a two level page table the single pmd is freed - * as the pgd. pmd_free_tlb checks the asce_limit against 2GB - * to avoid the double free of the pmd in this case. - */ -static inline void pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd) -{ -#ifdef __s390x__ - if (tlb->mm->context.asce_limit <= (1UL << 31)) - return; - if (!tlb->fullmm) { - tlb->array[--tlb->nr_pxds] = pmd; - if (tlb->nr_ptes >= tlb->nr_pxds) - tlb_flush_mmu(tlb, 0, 0); - } else - pmd_free(tlb->mm, pmd); -#endif -} - -/* - * pud_free_tlb frees a pud table and clears the CRSTE for the - * region third table entry from the tlb. - * If the mm uses a three level page table the single pud is freed - * as the pgd. pud_free_tlb checks the asce_limit against 4TB - * to avoid the double free of the pud in this case. - */ -static inline void pud_free_tlb(struct mmu_gather *tlb, pud_t *pud) -{ -#ifdef __s390x__ - if (tlb->mm->context.asce_limit <= (1UL << 42)) - return; - if (!tlb->fullmm) { - tlb->array[--tlb->nr_pxds] = pud; - if (tlb->nr_ptes >= tlb->nr_pxds) - tlb_flush_mmu(tlb, 0, 0); - } else - pud_free(tlb->mm, pud); -#endif -} - -#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_migrate_finish(mm) do { } while (0) - -#endif /* _S390_TLB_H */ |