1 /* arch/sparc64/mm/tlb.c
3 * Copyright (C) 2004 David S. Miller <davem@redhat.com>
6 #include <linux/kernel.h>
7 #include <linux/percpu.h>
9 #include <linux/swap.h>
10 #include <linux/preempt.h>
12 #include <asm/pgtable.h>
13 #include <asm/pgalloc.h>
14 #include <asm/tlbflush.h>
15 #include <asm/cacheflush.h>
16 #include <asm/mmu_context.h>
19 /* Heavily inspired by the ppc64 code. */
21 static DEFINE_PER_CPU(struct tlb_batch, tlb_batch);
23 void flush_tlb_pending(void)
25 struct tlb_batch *tb = &get_cpu_var(tlb_batch);
26 struct mm_struct *mm = tb->mm;
33 if (CTX_VALID(mm->context)) {
34 if (tb->tlb_nr == 1) {
35 global_flush_tlb_page(mm, tb->vaddrs[0]);
38 smp_flush_tlb_pending(tb->mm, tb->tlb_nr,
41 __flush_tlb_pending(CTX_HWBITS(tb->mm->context),
42 tb->tlb_nr, &tb->vaddrs[0]);
50 put_cpu_var(tlb_batch);
53 void arch_enter_lazy_mmu_mode(void)
55 struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
60 void arch_leave_lazy_mmu_mode(void)
62 struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
69 static void tlb_batch_add_one(struct mm_struct *mm, unsigned long vaddr,
72 struct tlb_batch *tb = &get_cpu_var(tlb_batch);
81 if (unlikely(nr != 0 && mm != tb->mm)) {
87 flush_tsb_user_page(mm, vaddr, huge);
88 global_flush_tlb_page(mm, vaddr);
97 if (tb->huge != huge) {
103 tb->vaddrs[nr] = vaddr;
105 if (nr >= TLB_BATCH_NR)
109 put_cpu_var(tlb_batch);
112 void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
113 pte_t *ptep, pte_t orig, int fullmm)
115 bool huge = is_hugetlb_pte(orig);
117 if (tlb_type != hypervisor &&
119 unsigned long paddr, pfn = pte_pfn(orig);
120 struct address_space *mapping;
126 page = pfn_to_page(pfn);
127 if (PageReserved(page))
130 /* A real file page? */
131 mapping = page_mapping(page);
135 paddr = (unsigned long) page_address(page);
136 if ((paddr ^ vaddr) & (1 << 13))
137 flush_dcache_page_all(mm, page);
142 tlb_batch_add_one(mm, vaddr, pte_exec(orig), huge);
145 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
146 static void tlb_batch_pmd_scan(struct mm_struct *mm, unsigned long vaddr,
152 pte = pte_offset_map(&pmd, vaddr);
153 end = vaddr + HPAGE_SIZE;
154 while (vaddr < end) {
155 if (pte_val(*pte) & _PAGE_VALID) {
156 bool exec = pte_exec(*pte);
158 tlb_batch_add_one(mm, vaddr, exec, false);
167 static void __set_pmd_acct(struct mm_struct *mm, unsigned long addr,
168 pmd_t orig, pmd_t pmd)
173 if ((pmd_val(pmd) ^ pmd_val(orig)) & _PAGE_PMD_HUGE) {
175 * Note that this routine only sets pmds for THP pages.
176 * Hugetlb pages are handled elsewhere. We need to check
177 * for huge zero page. Huge zero pages are like hugetlb
178 * pages in that there is no RSS, but there is the need
179 * for TSB entries. So, huge zero page counts go into
182 if (pmd_val(pmd) & _PAGE_PMD_HUGE) {
183 if (is_huge_zero_page(pmd_page(pmd)))
184 mm->context.hugetlb_pte_count++;
186 mm->context.thp_pte_count++;
188 if (is_huge_zero_page(pmd_page(orig)))
189 mm->context.hugetlb_pte_count--;
191 mm->context.thp_pte_count--;
194 /* Do not try to allocate the TSB hash table if we
195 * don't have one already. We have various locks held
196 * and thus we'll end up doing a GFP_KERNEL allocation
197 * in an atomic context.
199 * Instead, we let the first TLB miss on a hugepage
204 if (!pmd_none(orig)) {
206 if (pmd_trans_huge(orig)) {
207 pte_t orig_pte = __pte(pmd_val(orig));
208 bool exec = pte_exec(orig_pte);
210 tlb_batch_add_one(mm, addr, exec, true);
211 tlb_batch_add_one(mm, addr + REAL_HPAGE_SIZE, exec,
214 tlb_batch_pmd_scan(mm, addr, orig);
219 void set_pmd_at(struct mm_struct *mm, unsigned long addr,
220 pmd_t *pmdp, pmd_t pmd)
225 __set_pmd_acct(mm, addr, orig, pmd);
228 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
229 unsigned long address, pmd_t *pmdp, pmd_t pmd)
235 } while (cmpxchg64(&pmdp->pmd, old.pmd, pmd.pmd) != old.pmd);
236 __set_pmd_acct(vma->vm_mm, address, old, pmd);
242 * This routine is only called when splitting a THP
244 pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
249 entry = __pmd(pmd_val(*pmdp) & ~_PAGE_VALID);
250 old = pmdp_establish(vma, address, pmdp, entry);
251 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
254 * set_pmd_at() will not be called in a way to decrement
255 * thp_pte_count when splitting a THP, so do it now.
256 * Sanity check pmd before doing the actual decrement.
258 if ((pmd_val(entry) & _PAGE_PMD_HUGE) &&
259 !is_huge_zero_page(pmd_page(entry)))
260 (vma->vm_mm)->context.thp_pte_count--;
265 void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
268 struct list_head *lh = (struct list_head *) pgtable;
270 assert_spin_locked(&mm->page_table_lock);
273 if (!pmd_huge_pte(mm, pmdp))
276 list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
277 pmd_huge_pte(mm, pmdp) = pgtable;
280 pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
282 struct list_head *lh;
285 assert_spin_locked(&mm->page_table_lock);
288 pgtable = pmd_huge_pte(mm, pmdp);
289 lh = (struct list_head *) pgtable;
291 pmd_huge_pte(mm, pmdp) = NULL;
293 pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
296 pte_val(pgtable[0]) = 0;
297 pte_val(pgtable[1]) = 0;
301 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */