1 files changed, 101 insertions, 0 deletions

diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 809eecf6c797..12ef4ea60c88 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -2467,3 +2467,104 @@ void __flush_tlb_all(void)
         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
                              : : "r" (pstate));
 }
+
+static pte_t *get_from_cache(struct mm_struct *mm)
+{
+        struct page *page;
+        pte_t *ret;
+
+        spin_lock(&mm->page_table_lock);
+        page = mm->context.pgtable_page;
+        ret = NULL;
+        if (page) {
+                void *p = page_address(page);
+
+                mm->context.pgtable_page = NULL;
+
+                ret = (pte_t *) (p + (PAGE_SIZE / 2));
+        }
+        spin_unlock(&mm->page_table_lock);
+
+        return ret;
+}
+
+static struct page *__alloc_for_cache(struct mm_struct *mm)
+{
+        struct page *page = alloc_page(GFP_KERNEL | __GFP_NOTRACK |
+                                       __GFP_REPEAT | __GFP_ZERO);
+
+        if (page) {
+                spin_lock(&mm->page_table_lock);
+                if (!mm->context.pgtable_page) {
+                        atomic_set(&page->_count, 2);
+                        mm->context.pgtable_page = page;
+                }
+                spin_unlock(&mm->page_table_lock);
+        }
+        return page;
+}
+
+pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
+                            unsigned long address)
+{
+        struct page *page;
+        pte_t *pte;
+
+        pte = get_from_cache(mm);
+        if (pte)
+                return pte;
+
+        page = __alloc_for_cache(mm);
+        if (page)
+                pte = (pte_t *) page_address(page);
+
+        return pte;
+}
+
+pgtable_t pte_alloc_one(struct mm_struct *mm,
+                        unsigned long address)
+{
+        struct page *page;
+        pte_t *pte;
+
+        pte = get_from_cache(mm);
+        if (pte)
+                return pte;
+
+        page = __alloc_for_cache(mm);
+        if (page) {
+                pgtable_page_ctor(page);
+                pte = (pte_t *) page_address(page);
+        }
+
+        return pte;
+}
+
+void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
+{
+        struct page *page = virt_to_page(pte);
+        if (put_page_testzero(page))
+                free_hot_cold_page(page, 0);
+}
+
+static void __pte_free(pgtable_t pte)
+{
+        struct page *page = virt_to_page(pte);
+        if (put_page_testzero(page)) {
+                pgtable_page_dtor(page);
+                free_hot_cold_page(page, 0);
+        }
+}
+
+void pte_free(struct mm_struct *mm, pgtable_t pte)
+{
+        __pte_free(pte);
+}
+
+void pgtable_free(void *table, bool is_page)
+{
+        if (is_page)
+                __pte_free(table);
+        else
+                kmem_cache_free(pgtable_cache, table);
+}