fix tlb flushing for page table pages

[linux-flexiantxendom0.git] / arch / s390 / include / asm / tlb.h

diff --git a/arch/s390/include/asm/tlb.h b/arch/s390/include/asm/tlb.h
index 81150b0..775a5ee 100644 (file)
--- a/arch/s390/include/asm/tlb.h
+++ b/arch/s390/include/asm/tlb.h
@@ -22,71 +22,63 @@
  */
 
 #include <linux/mm.h>
+#include <linux/pagemap.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;
+       struct mmu_table_batch *batch;
        unsigned int fullmm;
-       unsigned int nr_ptes;
-       unsigned int nr_pxds;
-       void *array[TLB_NR_PTRS];
 };
 
-DECLARE_PER_CPU(struct mmu_gather, mmu_gathers);
+struct mmu_table_batch {
+       struct rcu_head         rcu;
+       unsigned int            nr;
+       void                    *tables[0];
+};
+
+#define MAX_TABLE_BATCH                \
+       ((PAGE_SIZE - sizeof(struct mmu_table_batch)) / sizeof(void *))
 
-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);
+extern void tlb_table_flush(struct mmu_gather *tlb);
+extern void tlb_remove_table(struct mmu_gather *tlb, void *table);
 
+static inline void tlb_gather_mmu(struct mmu_gather *tlb,
+                                 struct mm_struct *mm,
+                                 unsigned int full_mm_flush)
+{
        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;
+       tlb->fullmm = full_mm_flush;
+       tlb->batch = NULL;
        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)
+static inline void tlb_flush_mmu(struct mmu_gather *tlb)
 {
-       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++]);
+       tlb_table_flush(tlb);
 }
 
 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);
+       tlb_table_flush(tlb);
 }
 
 /*
  * 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
+ * tlb_ptep_clear_flush. In both flush modes the tlb for a page cache page
  * has already been freed, so just do free_page_and_swap_cache.
  */
+static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page)
+{
+       free_page_and_swap_cache(page);
+       return 1; /* avoid calling tlb_flush_mmu */
+}
+
 static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
 {
        free_page_and_swap_cache(page);
@@ -99,12 +91,9 @@ static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
 static inline void pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
                                unsigned long address)
 {
-       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);
+       if (!tlb->fullmm)
+               return page_table_free_rcu(tlb, (unsigned long *) pte);
+       page_table_free(tlb->mm, (unsigned long *) pte);
 }
 
 /*
@@ -120,12 +109,9 @@ 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);
+       if (!tlb->fullmm)
+               return tlb_remove_table(tlb, pmd);
+       crst_table_free(tlb->mm, (unsigned long *) pmd);
 #endif
 }
 
@@ -142,12 +128,9 @@ 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);
+       if (!tlb->fullmm)
+               return tlb_remove_table(tlb, pud);
+       crst_table_free(tlb->mm, (unsigned long *) pud);
 #endif
 }