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-rw-r--r--include/asm-s390/tlb.h156
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 3d8a96d39d9..00000000000
--- 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 */